Citations
All
Search in:AllTitleAbstractAuthor name
Publications
(51K+)
Patents
Grants
Pathways
Clinical trials
Publication
Journal: Kidney International
February/12/1991
Abstract
Soft tissue calcification is a recognized complication of uremia in adult patients and has been implicated as a cause of ischemic necrosis, cardiac arrhythmias, and respiratory failure. However, soft tissue calcification has been regarded as rare in pediatric renal patients. Following a sudden death due to pulmonary calcinosis in an adolescent after renal transplantation, we retrospectively reviewed clinical, biochemical and autopsy data of 120 patients with uremia, on dialysis, or following renal transplantation cared for at Childrens Hospital of Los Angeles from 1960 to 1983. Soft tissue calcification was found in 72 of 120 patients (60 percent). Forty-three patients (36 percent) had systemic calcinosis (Group A): the most frequent sites of mineral deposition were blood vessels, lung, kidney, myocardium, coronary artery, central nervous system, and gastric mucosa. Vascular calcification was uniformly accompanied by deposits in other organs. Twenty-nine patients had small amounts of focal calcification (Group B) and 48 patients had no soft tissue calcification (Group C). By multiple logistic regression analysis, the use of vitamin D or its analogues, the form of vitamin D medication prescribed, the peak calcium x phosphorus product, the age at onset of renal failure, and male sex were jointly associated with calcinosis (Group A). Vitamin D therapy showed the strongest independent association with calcinosis and the probability of calcinosis was greater in patients receiving calcitriol when compared with dihydrotachysterol and vitamin D2 or D3. The duration of renal failure, peak serum calcium, serum calcium at death, serum phosphorus at death, and primary renal diagnosis, were not statistically associated with calcinosis.(ABSTRACT TRUNCATED AT 250 WORDS)
Publication
Journal: Journal of Comparative Neurology
November/2/1992
Abstract
The medial and central segments of the mediodorsal nucleus of the thalamus (MD) receive afferents from the ventral forebrain, including the piriform cortex, the ventral pallidum, and the amygdaloid complex. Because MD is reciprocally interconnected with prefrontal and agranular insular cortical areas, it provides a relay of ventral forebrain activity to these cortical areas. However, there are also direct projections from the piriform cortex and the amygdala to the prefrontal and agranular insular cortices. This study addresses whether this system has a "triangular" organization, such that structures in the ventral forebrain project to interconnected areas in MD and the prefrontal/insular cortex. The thalamocortical projections of MD have been studied in experiments with injections of retrograde tracers into prefrontal or agranular insular cortical areas. In many of the same experiments, projections from the ventral forebrain to MD and to the prefrontal/insular cortex have been demonstrated with anterograde axonal tracers. The connections of the piriform cortex (PC) with MD and the prefrontal/insular cortex form an organized triangular system. The PC projections to the central and medial segments of MD and to the lateral orbital cortex (LO) and the ventral and posterior agranular insular cortices (AIv and AIp) are topographically organized, such that more caudal parts of PC tend to project more medially in MD and more caudally within the orbital/insular cortex. The central and medial portions of MD also send matching, topographically organized projections to LO, AIv and AIp, with more medial parts of MD projecting further caudally. The anterior cortical nucleus of the amygdala (COa) also projects to the dorsal part of the medial segment of MD and to its cortical targets, the medial orbital area (MO) and AIp. The projections of the basal/accessory basal amygdaloid nuclei to MD and to prefrontal cortex, and from MD to amygdaloceptive parts of prefrontal cortex, are not as tightly organized. Amygdalothalamic afferents in MD are concentrated in the dorsal half of the medial segment. Cells in this part of the nucleus project to the amygdaloceptive prelimbic area (PL) and AIp. However, other amygdaloceptive prefrontal areas are connected to parts of MD that do not receive fibers from the amygdala. Ventral pallidal afferents are distributed to all parts of the central and medial segments of MD, overlapping with the fibers from the amygdala and piriform cortex. Fibers from other parts of the pallidum, or related areas such as the substantia nigra, pars reticulata, terminate in the lateral and ventral parts of MD, where they overlap with inputs from the superior colliculus and other brainstem structures.(ABSTRACT TRUNCATED AT 400 WORDS)
Publication
Journal: Journal of Immunology
January/13/2014
Abstract
In the infarcted myocardium, activation of the inflammatory cascade clears the wound from dead cells, whereas stimulating matrix degradation and chamber dilation, thus contributing to the development of heart failure. IL-1 is critically involved in the postinfarction inflammatory reaction and mediates adverse dilative remodeling. We hypothesized that IL-1 may regulate postinfarction repair and remodeling through cell-specific actions on leukocytes and fibroblasts. Flow cytometry demonstrated that in mouse infarcts, early recruitment of proinflammatory Ly6C(hi) cells expressing IL-1R1, the signaling receptor for IL-1, was followed by infiltration with cells expressing the decoy receptor, IL-1R2. Increased expression of IL-1R2 may serve to terminate IL-1-driven inflammation after infarction. Loss of IL-1 signaling in IL-1R1 null mice globally attenuated leukocyte recruitment, reducing the number of infiltrating Ly6C(hi) and Ly6C(lo) cells. Nonmyeloid CD11b(-) cells harvested during the inflammatory phase of cardiac repair exhibited marked upregulation of chemokines and cytokines; their inflammatory activation was IL-1R1 dependent. Moreover, IL-1β attenuated TGF-β-induced contractile activity of fibroblasts populating collagen pads, attenuated α-smooth muscle actin expression, and stimulated matrix metalloproteinase synthesis in an IL-1R1-dependent manner. The effects of IL-1 on TGF-β responses in cardiac fibroblasts were not due to direct effects on Smad activation, but were associated with endoglin suppression and accentuated expression of bone morphogenetic protein and activin membrane-bound inhibitor, a negative regulator of TGF-β signaling. IL-1 may orchestrate fibroblast responses in the infarct; early stimulation of fibroblast IL-1R1 signaling during the inflammatory phase may prevent premature activation of a matrix-synthetic contractile phenotype until the wound is cleared, and the infarct microenvironment can support mesenchymal cell growth.
Publication
Journal: Structural Equation Modeling
February/19/2017
Abstract
Little research has examined factors influencing statistical power to detect the correct number of latent classes using latent profile analysis (LPA). This simulation study examined power related to inter-class distance between latent classes given true number of classes, sample size, and number of indicators. Seven model selection methods were evaluated. None had adequate power to select the correct number of classes with a small (Cohen's d = .2) or medium (d = .5) degree of separation. With a very large degree of separation (d = 1.5), the Lo-Mendell-Rubin test (LMR), adjusted LMR, bootstrap likelihood-ratio test, BIC, and sample-size adjusted BIC were good at selecting the correct number of classes. However, with a large degree of separation (d = .8), power depended on number of indicators and sample size. The AIC and entropy poorly selected the correct number of classes, regardless of degree of separation, number of indicators, or sample size.
Publication
Journal: Tissue engineering
December/21/2006
Abstract
To generate an ''off the shelf'' tissue-engineered heart valve, the cells would need to be of allogeneic origin. Here, we report the possibility of using human bone marrow-derived mesenchymal stem cells (MSCs) as a suitable allogeneic cell source for tissue-engineered heart valves. Proliferative responses of primary and primed CD4+ T cells to allogeneic MSCs were examined. A protein microarray system was used to detect soluble factors from supernatants collected from the T cell assays. MSCs are poor stimulators of primary and primed CD4+ T cell proliferation, despite provision of B7-1 trans-co-stimulation. MSCs not only directly inhibited primary and primed T cell responses to allogeneic peripheral blood mononuclear cells (PBMCs), but 24-h pre-culture of T cells with MSCs suppressed subsequent T cell proliferative responses to allogeneic PBMCs in a contact-dependent manner. Analysis of supernatants revealed a distinctly different cytokine profile after co-culture of T cells with MSCs than with PBMCs or endothelial cells. Pro-inflammatory Th1 cytokines interleukin (IL)-1alpha and beta, interferon (IFN)gamma, and tumor necrosis factor (TNF)alpha were downregulated, whereas, anti-inflammatory Th2 cytokines IL-3, IL-5, IL-10, and IL-13 and the Th2 chemokine I-309, a chemoattractant for regulatory T cells, were upregulated. Further analysis revealed that after co-culture with MSCs, the T cells exhibited a regulatory phenotype (CD4+ CD25(lo) CD69(lo) FoxP3+). MSCs downregulate T cell responses through direct contact and secretion of anti-inflammatory and tolerogenic cytokines, which may involve the recruitment of regulatory T cells. This implies that allogeneic MSCs could be a suitable cell source for tissue engineering a heart valve.
Publication
Journal: Journal of the American College of Cardiology
September/15/2014
Abstract
BACKGROUND
Various national campaigns launched in recent years have focused on young women with acute myocardial infarctions (AMIs). Contemporary longitudinal data about sex differences in clinical characteristics, hospitalization rates, length of stay (LOS), and mortality have not been examined.
OBJECTIVE
This study sought to determine sex differences in clinical characteristics, hospitalization rates, LOS, and in-hospital mortality by age group and race among young patients with AMIs using a large national dataset of U.S. hospital discharges.
METHODS
Using the National Inpatient Sample, clinical characteristics, AMI hospitalization rates, LOS, and in-hospital mortality were compared for patients with AMI across ages 30 to 54 years, dividing them into 5-year subgroups from 2001 to 2010, using survey data analysis techniques.
RESULTS
A total of 230,684 hospitalizations were identified with principal discharge diagnoses of AMI in 30- to 54-year-old patients from Nationwide Inpatient Sample data, representing an estimated 1,129,949 hospitalizations in the United States from 2001 to 2010. No statistically significant declines in AMI hospitalization rates were observed in the age groups <55 years or stratified by sex. Prevalence of comorbidities was higher in women and increased among both sexes through the study period. Women had longer LOS and higher in-hospital mortality than men across all age groups. However, observed in-hospital mortality declined significantly for women from 2001 to 2010 (from 3.3% to 2.3%, relative change 30.5%; p for trend < 0.0001) but not for men (from 2% to 1.8%, relative change 8.6%; p for trend = 0.60).
CONCLUSIONS
AMI hospitalization rates for young people have not declined over the past decade. Young women with AMIs have more comorbidity, longer LOS, and higher in-hospital mortality than young men, although their mortality rates are decreasing.
Publication
Journal: Journal of Applied Physiology
January/30/1992
Abstract
Spectral analysis of heart rate variability (HRV) might provide an index of relative sympathetic (SNS) and parasympathetic nervous system (PNS) activity during exercise. Eight subjects completed six 17-min submaximal exercise tests and one resting measurement in the upright sitting position. During submaximal tests, work rate (WR) was increased for the initial 3 min in a ramp fashion until it reached constant WRs of 20 W, or 30, 60, 90, 100, and 110% of the predetermined ventilatory threshold (Tvent). Ventilatory profile and alveolar gas exchange were monitored breath by breath, and beat-to-beat HRV was measured as R-R intervals of an electrocardiogram. Spectral analysis was applied to the HRV from 7 to 17 min. Low-frequency (0-0.15 Hz) and high-frequency (0.15-1.0 Hz) areas under power spectra (LO and HI, respectively) were calculated. The indicator of PNS activity (HI) decreased dramatically (P less than 0.05) when the subjects exercised compared with rest and continued to decrease until the intensity reached 60% Tvent. The indicator of SNS activity (LO/HI) remained unchanged up to 100% Tvent, whereas it increased abruptly (P less than 0.05) at 110% Tvent. The results suggested that (cardiac) PNS activity decreased progressively from rest to a WR equivalent to 60% Tvent, and SNS activity increased only when exercise intensity exceeded Tvent.
Publication
Journal: Journal of Experimental Medicine
December/13/2007
Abstract
Interferon-producing killer dendritic cells (IKDCs) are a recently described subset of CD11c(lo)B220(+) cells that share phenotypic and functional properties of DCs and natural killer (NK) cells (Chan, C.W., E. Crafton, H.N. Fan, J. Flook, K. Yoshimura, M. Skarica, D. Brockstedt, T.W. Dubensky, M.F. Stins, L.L. Lanier, et al. 2006. Nat. Med. 12:207-213; Taieb, J., N. Chaput, C. Menard, L. Apetoh, E. Ullrich, M. Bonmort, M. Pequignot, N. Casares, M. Terme, C. Flament, et al. 2006. Nat. Med. 12:214-219). IKDC development appears unusual in that cytokines using the interleukin (IL)-2 receptor beta (IL-2Rbeta) chain but not those using the common gamma chain (gamma(c)) are necessary for their generation. By directly comparing Rag2(-/-)gamma(c)(-/y), Rag2(-/-)IL-2Rbeta(-/-), Rag2(-/-)IL-15(-/-), and Rag2(-/-)IL-2(-/-) mice, we demonstrate that IKDC development parallels NK cell development in its strict IL-15 dependence. Moreover, IKDCs uniformly express NK-specific Ncr-1 transcripts (encoding NKp46), whereas NKp46(+) cells are absent in Ncr1(gfp/+)gamma(c)(-/y) mice. Distinguishing features of IKDCs (CD11c(lo)B220(+)MHC-II(+)) were carefully examined on developing NK cells in the bone marrow and on peripheral NK cells. As B220 expression was heterogeneous, defining B220(lo) versus B220(hi) NK1.1(+) NK cells could be considered as arbitrary, and few phenotypic differences were noted between NK1.1(+) NK cells bearing different levels of B220. CD11c expression did not correlate with B220 or major histocompatibility complex (MHC) class II (MHC-II) expression, and most MHC-II(+) NK1.1(+) cells did not express B220 and were thus not IKDCs. Finally, CD11c, MHC-II, and B220 levels were up-regulated on NK1.1(+) cells upon activation in vitro or in vivo in a proliferation-dependent fashion. Our data suggest that the majority of CD11c(lo)B220(+) "IKDC-like" cells represent activated NK cells.
Publication
Journal: International Journal of Cancer
July/28/2002
Abstract
In recent years, breast cancer incidence rates have fluctuated over relatively short time spans; examination of these patterns can provide etiologic clues and direction for prevention programs. Asian-American women are generally considered to be at lower risk of breast cancer than other ethnic groups. However, their rates are typically based on an aggregation of ethnic Asian populations, which may obscure important ethnic differences in risk. Detailed analyses of the trends in ethnic-specific incidence rates will provide more information than when ethnicities are combined. Los Angeles County, California, the most populous and probably the most ethnically diverse county in the United States, has a large multi-ethnic Asian-American population. Trends in invasive female breast cancer incidence were examined using data from the Los Angeles Cancer Surveillance Program, the population-based cancer registry covering the County. Although overall breast cancer incidence rates remained stable in the late 1980s and early 1990s, data for the most recent 5-year period suggest that incidence may again be increasing for Asian-American and non-Hispanic white women over age 50 (estimated annual percent change = 6.3%, p < 0.05 and 1.5%, p < 0.05, respectively), although little change has occurred among black and Hispanic women. Invasive breast cancer incidence rates for Asian-American ethnic groups are heterogeneous and, for most, are increasing. In Los Angeles County, rates for Japanese-American women have increased rapidly since 1988 and are now approaching rates for non-Hispanic white women. Rates among Filipinas, who have historically had higher rates than their other Asian-American counterparts, are not increasing as rapidly as rates for Japanese women, but remain relatively high. Breast cancer risk among women of Japanese and Filipino ancestry is twice that of Chinese and Korean women. Asian women, who commonly have low breast cancer rates in their native countries, typically experience increasing breast cancer incidence after immigrating to the United States. Ethnic-specific incidence rates show that Japanese-Americans, the first Asian population to immigrate to Los Angeles County in large numbers and the most acculturated, have experienced a rapid increase in breast cancer incidence. Japanese-American rates in Los Angeles County may have already surpassed those of non-Hispanic whites if recent trends have continued unabated.
Publication
Journal: Infection and Immunity
August/22/1991
Abstract
The mouse and rabbit intradermal injection models have been used to define factors that may be important in Haemophilus ducreyi pathogenesis. We used H. ducreyi strains with diverse geographic origins and phenotypic characteristics to evaluate the experimental models. Injection of live and heat-killed bacteria caused skin abscesses in both models. Semiquantitative cultures of skin injected with live bacteria showed that H. ducreyi failed to replicate in animal tissue. These data suggested that the experimental lesions were caused by a heat-stable substance such as lipooligosaccharide (LOS). In mice, injection of H. ducreyi and Haemophilus influenzae LOS and Escherichia coli lipopolysaccharide caused mild to moderate inflammation. In rabbits, injection of H. ducreyi LOS caused intradermal abscesses that were histologically similar to those caused by live and heat-killed bacteria. H. ducreyi and Neisseria gonorrhoeae LOS caused significantly larger lesions than equivalent amounts of H. influenzae LOS and E. coli lipopolysaccharide in the rabbit model. We conclude that the intradermal injection models are not valid models to study the growth of H. ducreyi in vivo. However, these data indicate that H. ducreyi LOS may play an important role in the pathogenesis of chancroid and that the rabbit model should be useful in studying H. ducreyi LOS toxicity at the cellular level.
Publication
Journal: Infection and Immunity
April/22/1992
Abstract
The lipooligosaccharides (LOS) of strains of Haemophilus ducreyi, Neisseria gonorrhoeae, Neisseria meningitidis, and Neisseria lactamica contain epitopes that are antigenically and structurally similar to carbohydrates present in human glycosphingolipids. LOS from strains of Haemophilus influenzae and H. influenzae biogroup aegyptius were tested for the binding of monoclonal antibodies (MAbs) that bind to human glycosphingolipids possessing Gal beta 1-4GlcNAc (MAb 3F11) and Gal alpha 1-4Gal beta 1-4Glc (MAb anti-Pk). In solid-phase radioimmunoassays, the LOS of 18 of 19 H. influenzae type b (Hib), 8 of 19 nontypeable H. influenzae, and 10 of 20 H. influenzae biogroup aegyptius strains bound MAb anti-Pk. The LOS of 13 of 19 Hib, 10 of 16 nontypeable H. influenzae, and 2 of 18 H. influenzae biogroup aegyptius strains bound MAb 3F11. Neuraminidase treatment of the strains increased the binding of MAb 3F11 by more than twofold in 47% of the H. influenzae strains, suggesting that sialic acid occluded the LOS structure recognized by MAb 3F11. The material released from neuraminidase-treated Hib LOS was confirmed to be sialic acid by high-performance anion-exchange chromatography. A recombinant plasmid containing genes involved in Hib LOS biosynthesis directed the expression (assembly) of the 3F11 epitope in Escherichia coli. These studies demonstrate that H. influenzae and H. influenzae biogroup aegyptius express at least two LOS epitopes that are similar to those present in human glycosphingolipids. Sialic acid was present on the LOS of some H. influenzae strains and prevented the binding of MAb 3F11 to its epitope. The oligosaccharide portion of sialylated LOS may also resemble sialylated oligosaccharides present in human glycosphingolipids (gangliosides).
Publication
Journal: Journal of Physiology
August/7/1991
Abstract
1. The length of muscle fibres in the medial gastrocnemius (MG) muscle of the anaesthetized cat was measured using ultrasound techniques. During the course of 'isometric' contractions, the muscle fibres shortened by stretching the compliant tendons, until the muscle fibres could no longer produce enough force to stretch the tendons further. At optimal muscle length (Lo) the maximal shortening of muscle fibres was 28%. 2. At muscle lengths much longer than Lo, 'isometric' contractions produced a slow shortening of the muscle fibres as the tendons were stretched and this resulted in a slow rise in tension. This phenomenon, usually referred to as 'creep', is due to low power at long muscle fibre length. This study shows that the series compliance present in the tendons is the major contributor to 'creep' in the cat MG muscle. As the tendons stretched during the course of the contraction, the average sarcomere length became shorter providing greater filament overlap and increasing power. 3. Slow to medium speed stretches applied shortly after the onset of contraction, as occurs in cat MG during walking and trotting, were entirely taken up in the tendons and the muscle fibres actually shortened throughout the imposed muscle stretch. 4. When early stretches were applied at muscle lengths longer than Lo, stretch of the muscle resulted in a peak force that was less than if the stretch had not been applied. This was the reverse of the situation for stretches at lengths less than Lo. When stretch was applied after attaining peak force, the force was greatly enhanced and the muscle fibres were also stretched. 5. Using the same techniques in a freely walking cat, the muscle fibres shortened by 1.0 +/- 0.3 mm during the stance phase of the step-cycle when the muscle was being stretched, in 198 consecutive step-cycles. 6. The tendons act as a mechanical buffer to protect muscle fibres from damage during eccentric contractions. 7. Since stretches of the MG muscle are not faithfully imposed on the muscle fibres, studies of muscle spindle function during locomotion need to take into consideration these effects of tendon compliance. The dominant view, when the foot lands on the ground during normal locomotion, is that muscle spindles are stretched along with the muscle resulting in reflex enhancement of contractile force. This study shows that the muscle fibres do not stretch under these circumstances, except at high speeds of locomotion when the stretch rate is also high.
Publication
Journal: Agents and actions
March/30/1986
Abstract
Inhibitors of arachidonic acid (AA) metabolism and other pharmacologic agents were evaluated against ear edema produced in mice by tetradecanoylphorbol acetate (TPA) or AA. Drugs were administered orally and topically either 30 min prior to AA or 30 min after TPA, except for steroids which were administered 2.5-3 hr prior to AA. Several cyclooxygenase (CO) inhibitors including indomethacin, aspirin, piroxicam and timegadine were without effect when administered orally against either irritant; the same drugs inhibited TPA edema when they were administered topically. Mixed CO/lipoxygenase (LO) inhibitors, phenidone and BW755C, were active orally against AA edema (ED50S of 84 and 65 mg/kg, respectively) and against TPA edema (ED50S of 235 and 88 mg/kg, respectively). Phenidone was more active topically against AA edema (ED50, 0.1 mg/ear) than BW755C (ED50, 2.8 mg/ear); however, BW755C was more active topically against TPA edema (ED50, 0.2 mg/ear) than phenidone (ED50, 0.6 mg/ear). Methylprednisolone was very effective in the AA (oral ED50, 17 mg/kg; topical ED50, greater than 1 mg/ear) and TPA models (oral ED50, 4.3 mg/kg; topical ED50, 0.03 mg/ear. MK-447 was topically and orally effective only in the TPA model. Not surprisingly, drugs were more effective topically than orally in both mouse ear edema assays. The models were somewhat selective for CO and CO/LO inhibitors; however, dapsone was orally effective in the ear models, and a number of mediator antagonists and CNS drugs, especially anti-psychotics, were topically active primarily against TPA edema. These models may be useful for the detection of in vivo activity of CO/LO or 5-LO inhibitors.
Publication
Journal: Risk Analysis
May/7/2012
Abstract
Ground-level ozone (O(3)) and fine particulate matter (PM(2.5)) are associated with increased risk of mortality. We quantify the burden of modeled 2005 concentrations of O(3) and PM(2.5) on health in the United States. We use the photochemical Community Multiscale Air Quality (CMAQ) model in conjunction with ambient monitored data to create fused surfaces of summer season average 8-hour ozone and annual mean PM(2.5) levels at a 12 km grid resolution across the continental United States. Employing spatially resolved demographic and concentration data, we assess the spatial and age distribution of air-pollution-related mortality and morbidity. For both PM(2.5) and O(3) we also estimate: the percentage of total deaths due to each pollutant; the reduction in life years and life expectancy; and the deaths avoided according to hypothetical air quality improvements. Using PM(2.5) and O(3) mortality risk coefficients drawn from the long-term American Cancer Society (ACS) cohort study and National Mortality and Morbidity Air Pollution Study (NMMAPS), respectively, we estimate 130,000 PM(2.5) -related deaths and 4,700 ozone-related deaths to result from 2005 air quality levels. Among populations aged 65-99, we estimate nearly 1.1 million life years lost from PM(2.5) exposure and approximately 36,000 life years lost from ozone exposure. Among the 10 most populous counties, the percentage of deaths attributable to PM(2.5) and ozone ranges from 3.5% in San Jose to 10% in Los Angeles. These results show that despite significant improvements in air quality in recent decades, recent levels of PM(2.5) and ozone still pose a nontrivial risk to public health.
Publication
Journal: Circulation
September/15/2008
Abstract
BACKGROUND
Ly-6C(hi) monocytes are key contributors to atherosclerosis in mice. However, the manner in which Ly-6C(hi) monocytes selectively accumulate in atherosclerotic lesions is largely unknown. Monocyte homing to sites of atherosclerosis is primarily initiated by rolling on P- and E-selectin expressed on endothelium. We hypothesize that P-selectin glycoprotein ligand-1 (PSGL-1), the common ligand of P- and E-selectin on leukocytes, contributes to the preferential homing of Ly-6C(hi) monocytes to atherosclerotic lesions.
RESULTS
To test this hypothesis, we examined the expression and function of PSGL-1 on Ly-6C(hi) and Ly-6C(lo) monocytes from wild-type mice, ApoE(-/-) mice, and mice lacking both ApoE and PSGL-1 genes (ApoE(-/-)/PSGL-1(-/-)). We found that Ly-6C(hi) monocytes expressed a higher level of PSGL-1 and had enhanced binding to fluid-phase P- and E-selectin compared with Ly-6C(lo) monocytes. Under in vitro flow conditions, more Ly-6C(hi) monocytes rolled on P-, E-, and L-selectin at slower velocities than Ly-6C(lo) cells. In an ex vivo perfused carotid artery model, Ly-6C(hi) monocytes interacted preferentially with atherosclerotic endothelium compared with Ly-6C(lo) monocytes in a PSGL-1-dependent manner. In vivo, ApoE(-/-) mice lacking PSGL-1 had impaired Ly-6C(hi) monocyte recruitment to atherosclerotic lesions. Moreover, ApoE(-/-)/PSGL-1(-/-) mice exhibited significantly reduced monocyte infiltration in wire injury-induced neointima and in atherosclerotic lesions. ApoE(-/-)/PSGL-1(-/-) mice also developed smaller neointima and atherosclerotic plaques.
CONCLUSIONS
These data indicate that PSGL-1 is a new marker for Ly-6C(hi) monocytes and a major determinant for Ly-6C(hi) cell recruitment to sites of atherosclerosis in mice.
Pulse
Views:
10
Posts:
No posts
Rating:
Not rated
Publication
Journal: Leukemia
August/30/2007
Abstract
Aldehyde dehydrogenase (ALDH) activity is used to define normal hematopoietic stem cell (HSC), but its link to leukemic stem cells (LSC) in acute myeloid leukemia (AML) is currently unknown. We hypothesize that ALDH activity in AML might be correlated with the presence of LSC. Fifty-eight bone marrow (BM) samples were collected from AML (n=43), acute lymphoblastic leukemia (ALL) (n=8) and normal cases (n=7). In 14 AML cases, a high SSC(lo)ALDH(br) cell population was identified (ALDH(+)AML) (median: 14.89%, range: 5.65-48.01%), with the majority of the SSC(lo)ALDH(br) cells coexpressing CD34(+). In another 29 cases, there was undetectable (n=23) or rare (< or =5%) (n=6) SSC(lo)ALDH(br) population (ALDH(-)AML). Among other clinicopathologic variables, ALDH(+)AML was significantly associated with adverse cytogenetic abnormalities. CD34(+) BM cells from ALDH(+)AML engrafted significantly better in NOD/SCID mice (ALDH(+)AML: injected bone 21.11+/-9.07%; uninjected bone 1.52+/-0.75% vs ALDH(-)AML: injected bone 1.77+/-1.66% (P=0.05); uninjected bone 0.23+/-0.23% (P=0.03)) with the engrafting cells showing molecular and cytogenetic aberrations identical to the original clones. Normal BM contained a small SSC(lo)ALDH(br) population (median: 2.92%, range: 0.92-5.79%), but none of the ALL cases showed this fraction. In conclusion, SSC(lo)ALDH(br) cells in ALDH(+)AML might denote primitive LSC and confer an inferior prognosis in patients.
Publication
Journal: Nature Immunology
October/13/2009
Abstract
Themis (thymocyte-expressed molecule involved in selection), a member of a family of proteins with unknown functions, is highly conserved among vertebrates. Here we found that Themis had high expression in thymocytes between the pre-T cell antigen receptor (pre-TCR) and positive-selection checkpoints and low expression in mature T cells. Themis-deficient thymocytes showed defective positive selection, which resulted in fewer mature thymocytes. Negative selection was also impaired in Themis-deficient mice. A greater percentage of Themis-deficient T cells had CD4(+)CD25(+)Foxp3(+) regulatory and CD62L(lo)CD44(hi) memory phenotypes than did wild-type T cells. In support of the idea that Themis is involved in TCR signaling, this protein was phosphorylated quickly after TCR stimulation and was needed for optimal TCR-driven calcium mobilization and activation of the kinase Erk.
Publication
Journal: Molecular Microbiology
September/11/2000
Abstract
Ganglioside mimicry by Campylobacter jejuni lipo-oligosaccharide (LOS) is thought to be a critical factor in the triggering of the Guillain-Barré and Miller-Fisher syndrome neuropathies after C. jejuni infection. The combination of a completed genome sequence and a ganglioside GM1-like LOS structure makes C. jejuni NCTC 11168 a useful model strain for the identification and characterization of the genes involved in the biosynthesis of ganglioside-mimicking LOS. Genome analysis identified a putative LOS biosynthetic cluster and, from this, we describe a putative gene (ORF Cj1139c), which we have termed wlaN, with a significant level of similarity to a number of bacterial glycosyltransferases. Mutation of this gene in C. jejuni NCTC 11168 resulted in a LOS molecule of increased electrophoretic mobility, which also failed to bind cholera toxin. Comparison of LOS structural data from wild type and the mutant strain indicated lack of a terminal beta-1,3-linked galactose residue in the latter. The wlaN gene product was demonstrated unambiguously as a beta-1,3 galactosyltransferase responsible for converting GM2-like LOS structures to GM1-like by in vitro expression. We also show that the presence of an intragenic homopolymeric tract renders the expression of a functional wlaN gene product phase variable, resulting in distinct C. jejuni NCTC 11168 cell populations with alternate GM1 or GM2 ganglioside-mimicking LOS structures. The distribution of wlaN among a number of C. jejuni strains with known LOS structure was determined and, for C. jejuni NCTC 12500, similar wlaN gene phase variation was shown to occur, so that this strain has the potential to synthesize a GM1-like LOS structure as well as the ganglioside GM2-like LOS structure proposed in the literature.
Publication
Journal: The Journal of trauma
October/9/2002
Abstract
BACKGROUND
As the population ages, the elderly will constitute a prominent proportion of trauma patients. The elderly suffer more severe consequences from traumatic injuries compared with the young, presumably resulting in increased resource use. In this study, we sought to examine ICU resource use in trauma on the basis of age and injury severity.
METHODS
This study was a retrospective review of trauma registry data prospectively collected on 26,237 blunt trauma patients admitted to all trauma centers (n = 26) in one state over 24 months (January 1996-December 1997). Age-dependent and injury severity-dependent differences in mortality, ICU length of stay (LOS), and hospital LOS were evaluated by logistic regression analysis.
RESULTS
Elderly (age>> or = 65 years, n = 7,117) patients had significantly higher mortality rates than younger (age < 65 years) trauma patients after stratification by Injury Severity Score (ISS), Revised Trauma Score, and other preexisting comorbidities. Age>> 65 years was associated with a two- to threefold increased mortality risk in mild (ISS < 15, 3.2% vs. 0.4%; < 0.001), moderate (ISS 15-29, 19.7% vs. 5.4%; < 0.001), and severe traumatic injury (ISS>> or = 30, 47.8% vs. 21.7%; < 0.001) compared with patients aged < 65 years. Logistic regression analysis confirmed that elderly patients had a nearly twofold increased mortality risk (odds ratio, 1.87; confidence interval, 1.60-2.18; < 0.001). Elderly patients also had significantly longer hospital LOS after stratifying for severity of injury by ISS (1.9 fewer days in the age 18-45 group, 0.89 fewer days in the age 46-64 group compared with the age>> or = 65 group). Mortality rates were higher for men than for women only in the ISS < 15 (4.4% vs. 2.6%, < 0.001) and ISS 15 to 29 (21.7% vs. 17.6%, = 0.031) groups. ICU LOS was significantly decreased in elderly patients with ISS>> or = 30.
CONCLUSIONS
Age is confirmed as an independent predictor of outcome (mortality) in trauma after stratification for injury severity in this largest study of elderly trauma patients to date. Elderly patients with severe injury (ISS>> 30) have decreased ICU resource use secondary to associated increased mortality rates.
Publication
Journal: Neuropharmacology
July/16/2009
Abstract
The fatty-acid ethanolamide, oleoylethanolamide (OEA), is a naturally occurring lipid that regulates feeding and body weight [Rodriguez de Fonseca, F., Navarro, M., Gomez, R., Escuredo, L., Nava, F., Fu, J., Murillo-Rodriguez, E., Giuffrida, A., LoVerme, J., Gaetani, S., Kathuria, S., Gall, C., Piomelli, D., 2001. An anorexic lipid mediator regulated by feeding. Nature 414, 209-212], and serves as an endogenous agonist of peroxisome proliferator-activated receptor-alpha (PPAR-alpha) [Fu, J., Gaetani, S., Oveisi, F., Lo Verme, J., Serrano, A., Rodriguez De Fonseca, F., Rosengarth., A., Luecke, H., Di Giacomo, B., Tarzia, G., Piomelli, D., 2003. Oleoylethanolamide regulates feeding and body weight through activation of the nuclear receptor PPAR-alpha. Nature 425, 90-93], a ligand-activated transcription factor that regulates several aspects of lipid metabolism [. Peroxisome proliferator-activated receptors: nuclear control of metabolism. Endocr. Rev. 20, 649-688]). OEA reduces food intake in wild-type mice, but not in mice deficient in PPAR-alpha (PPAR-alpha(-/-)), an effect that is also observed with the PPAR-alpha agonists Wy-14643 and GW7647 [Brown, P.J., Chapman, J.M., Oplinger, J.A., Stuart, L.W., Willson, T.M. and Wu, Z., 2000. Chemical compounds as selective activators of PPAR-alpha. PCT Int. Appl., 32; . The PPARs: from orphan receptors to drug discovery. J. Med. Chem. 43, 527-550]. By contrast, specific agonists of PPAR-delta/beta (GW501516) or PPAR-gamma (ciglitazone) have no such effect. In obese Zucker rats, which lack functional leptin receptors, OEA reduces food intake and lowers body-weight gain along with plasma lipid levels. Similar effects are seen in diet-induced obese rats and mice. In the present study, we report that subchronic OEA treatment (5mgkg(-1), intraperitoneally, i.p., once daily for two weeks) in Zucker rats initiates transcription of PPAR-alpha and other PPAR-alpha target genes, including fatty-acid translocase (FAT/CD36), liver fatty-acid binding protein (L-FABP), and uncoupling protein-2 (UCP-2). Moreover, OEA decreases neutral lipid content in hepatocytes, as assessed by Oil red O staining, as well as serum cholesterol and triglyceride levels. The results suggest that OEA regulates lipid metabolism and that this effect may contribute to its anti-obesity properties.
Publication
Journal: Fertility and Sterility
June/2/1996
Abstract
OBJECTIVE
To determine whether semen quality has changed in the United States over the last 25 years.
METHODS
Retrospective review.
METHODS
Three U.S. sperm banks, Cryogenic Laboratories, Inc. (Roseville, Minnesota), Idant Laboratories (New York, New York), and California Cryobank, Inc. (Los Angeles, California).
METHODS
None.
METHODS
Age at sample collection, sperm concentration, volume, motility, and days of abstinence before sample collection were determined for each man. Linear and multiple regression analyses were used to assess changes in these characteristics over time.
RESULTS
Controlling for the effects of age and duration of abstinence, there was a slight but significant increase in mean sperm concentration but no change in either motility or semen volume over the 25-year period. Both sperm motility and semen volume decreased with increasing age at sample collection. Both sperm concentration and semen volume increased as a function of duration of abstinence. There were significant differences in mean (+/- SEM) sperm concentrations (10(6) sperm/mL) and motilities between the different sperm banks with California lowest (72.7 +/- 3.1, 51.4% +/- 1.1%, respectively), Minnesota higher (100.8 +/- 2.9, 56.0%, respectively), and New York highest (131.5 +/- 3.5, 58.2% +/- 0.5%, respectively).
CONCLUSIONS
Our data show no decline in sperm counts over a 25-year period in 1,283 men who banked sperm before vasectomy at three distinct geographical sites in the United States.
Publication
Journal: Academic Emergency Medicine
May/1/2012
Abstract
OBJECTIVE
Emergency department (ED) boarding has been associated with several negative patient-oriented outcomes, from worse satisfaction to higher inpatient mortality rates. The current study evaluates the association between length of ED boarding and outcomes. The authors expected that prolonged ED boarding of admitted patients would be associated with higher mortality rates and longer hospital lengths of stay (LOS).
METHODS
This was a retrospective cohort study set at a suburban academic ED with an annual ED census of 90,000 visits. Consecutive patients admitted to the hospital from the ED and discharged between October 2005 and September 2008 were included. An electronic medical record (EMR) system was used to extract patient demographics, ED disposition (discharge, admit to floor), ED and hospital LOS, and in-hospital mortality. Boarding was defined as ED LOS 2 hours or more after decision for admission. Descriptive statistics were used to evaluate the association between length of ED boarding and hospital LOS, subsequent transfer to an intensive care unit (ICU), and mortality controlling for comorbidities.
RESULTS
There were 41,256 admissions from the ED. Mortality generally increased with increasing boarding time, from 2.5% in patients boarded less than 2 hours to 4.5% in patients boarding 12 hours or more (p < 0.001). Mean hospital LOS also showed an increase with boarding time (p < 0.001), from 5.6 days (SD ± 11.4 days) for those who stayed in the ED for less than 2 hours to 8.7 days (SD ± 16.3 days) for those who boarded for more than 24 hours. The increases were still apparent after adjustment for comorbid conditions and other factors.
CONCLUSIONS
Hospital mortality and hospital LOS are associated with length of ED boarding.
Publication
Journal: Scientific Reports
September/21/2017
Abstract
Natural killer cells (NK) are highly enriched in the human liver, where they can regulate immunity and immunopathology. We probed them for a liver-resident subset, distinct from conventional bone-marrow-derived NK. CXCR6+ NK were strikingly enriched in healthy and diseased liver compared to blood (p < 0.0001). Human hepatic CXCR6+ NK had an immature phenotype (predominantly CD56(bright)CD16-CD57-), and expressed the tissue-residency marker CD69. CXCR6+ NK produced fewer cytotoxic mediators and pro-inflammatory cytokines than the non-liver-specific CXCR6- fraction. Instead CXCR6+ NK could upregulate TRAIL, a key death ligand in hepatitis pathogenesis. CXCR6 demarcated liver NK into two transcriptionally distinct populations: T-bet(hi)Eomes(lo)(CXCR6-) and T-bet(lo)Eomes(hi)(CXCR6+); the latter was virtually absent in the periphery. The small circulating CXCR6+ subset was predominantly T-bet(hi)Eomes(lo), suggesting its lineage was closer to CXCR6- peripheral than CXCR6+ liver NK. These data reveal a large subset of human liver-resident T-bet(lo)Eomes(hi) NK, distinguished by their surface expression of CXCR6, adapted for hepatic tolerance and inducible anti-viral immunity.
Publication
Journal: Behavioural Pharmacology
December/30/2008
Abstract
A positive relationship between the consumption of sweetened dietary substances (e.g. saccharin and sucrose) and drug abuse has been reported in both the human and other animal literature. The proposed genetic contribution to this relationship has been based on evidence from behavioral, neurobiological, and linkage studies in heterogeneous and homogeneous animal populations. Initial work in several laboratories indicated that rodents that are selected for high alcohol consumption also display an increased preference for sweets compared with low alcohol-consuming animals. More recently, Sprague-Dawley rats have been selectively bred based on high saccharin (HiS) or low saccharin (LoS) consumption, and these lines represent an ideal opportunity to determine whether a reciprocal genetic relationship exists between the consumption of sweetened substances and self-administration of drugs of abuse. The purpose of this review is to examine a series of studies on the HiS and LoS rats for drug-seeking and drug-taking behavior using laboratory animal models that represent critical phases of drug abuse in humans. The data support the hypothesis that sweet consumption and drug self-administration are closely related and genetically influenced. Other characteristics of HiS and LoS rats are discussed as possible mediators of the genetic differences such as activity, impulsivity, novelty reactivity, stress, and emotionality. The interaction of sweet preference with biological variables related to drug abuse, such as age, sex, and hormonal influences, was considered, as they may be additive vulnerability factors with consumption of sweet substances. In the studies that are discussed, the HiS and LoS lines emerge as ideal addiction-prone and addiction-resistant models, respectively, with vulnerability or resilience factors that will inform prevention and treatment strategies for drug abuse.
load more...