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Publication
Journal: Gut
January/13/2008
Abstract
OBJECTIVE
Empiric proton pump inhibitor (PPI) trials have become increasingly popular leading to gastroenterologists frequently evaluating gastro-oesophageal reflux disease (GORD) patients only after they have "failed" PPI therapy. Combined multichannel intraluminal impedance and pH (MII-pH) monitoring has the ability to detect gastro-oesophageal reflux (GOR) episodes independent of their pH and evaluate the relationship between symptoms and all types of GOR. Using this technique, we aimed to characterise the frequency of acid and non-acid reflux (NAR) and their relationship to typical and atypical GOR symptoms in patients on PPI therapy.
METHODS
Patients with persistent GORD symptoms referred to three centres underwent 24 hour combined MII-pH monitoring while taking PPIs at least twice daily. Reflux episodes were detected by impedance channels located 3, 5, 7, 9, 15, and 17 cm above the lower oesophageal sphincter (LOS) and classified into acid or non-acid based on pH data from 5 cm above the LOS. A positive symptom index (SI) was declared if at least half of each specific symptom events were preceded by reflux episodes within five minutes.
RESULTS
A total of 168 patients (103 (61%) females and 65 (39%) males; mean age 53 (range 18-85) years) underwent combined MII-pH monitoring while taking PPIs at least twice daily. One hundred and forty four (86%) patients recorded symptoms during the study day and 24 (15%) patients had no symptoms during testing. Sixty nine (48%) symptomatic patients had a positive SI for at least one symptom (16 (11%) with acid reflux and 53 (37%) with NAR) and 75 (52%) had a negative SI. A total of 171 (57%) typical GORD symptoms were recorded, 19 (11%) had a positive SI for acid reflux, 52 (31%) for NAR, and 100 (58%) had a negative SI. One hundred and thirty one (43%) atypical symptoms were recorded, four (3%) had a positive SI for acid reflux, 25 (19%) had a positive SI for NAR, and 102 (78%) had a negative SI.
CONCLUSIONS
Combined MII-pH identifies the relation of reflux of all types to persistent symptoms and the importance of NAR in patients taking PPIs.
Publication
Journal: Journal of the National Cancer Institute
May/17/2000
Abstract
BACKGROUND
Hormone replacement therapy (HRT) given as unopposed estrogen replacement therapy (ERT) gained widespread popularity in the United States in the 1960s and 1970s. Recent prescribing practices have favored combination HRT (CHRT), i.e., adding a progestin to estrogen for the entire monthly cycle (continuous combined replacement therapy [CCRT]) or a part of the cycle (sequential estrogen plus progestin therapy [SEPRT]). Few data exist on the association between CHRT and breast cancer risk. We determined the effects of CHRT on a woman's risk of developing breast cancer in a population-based, case-control study.
METHODS
Case subjects included those with incident breast cancers diagnosed over 4(1/2) years in Los Angeles County, CA, in the late 1980s and 1990s. Control subjects were neighborhood residents who were individually matched to case subjects on age and race. Case subjects and control subjects were interviewed in person to collect information on known breast cancer risk factors as well as on HRT use. Information on 1897 postmenopausal case subjects and on 1637 postmenopausal control subjects aged 55-72 years who had not undergone a simple hysterectomy was analyzed. Breast cancer risks associated with the various types of HRT were estimated as odds ratios (ORs) after adjusting simultaneously for the different forms of HRT and for known risk factors of breast cancer. All P values are two-sided.
RESULTS
HRT was associated with a 10% higher breast cancer risk for each 5 years of use (OR(5) = 1.10; 95% confidence interval [CI] = 1.02-1.18). Risk was substantially higher for CHRT use (OR(5) = 1.24; 95% CI = 1.07-1.45) than for ERT use (OR(5) = 1. 06; 95% CI = 0.97-1.15). Risk estimates were higher for SEPRT (OR(5) = 1.38; 95% CI = 1.13-1.68) than for CCRT (OR(5) = 1.09; 95% CI = 0. 88-1.35), but this difference was not statistically significant.
CONCLUSIONS
This study provides strong evidence that the addition of a progestin to HRT enhances markedly the risk of breast cancer relative to estrogen use alone. These findings have important implications for the risk-benefit equation for HRT in women using CHRT.
Publication
Journal: JAMA - Journal of the American Medical Association
September/27/1995
Abstract
OBJECTIVE
To study differences in the attitudes of elderly subjects from different ethnic groups toward disclosure of the diagnosis and prognosis of a terminal illness and toward end-of-life decision making.
METHODS
Survey.
METHODS
Thirty-one senior citizen centers within Los Angeles County, California.
METHODS
A stratified quota sample of 200 subjects aged 65 years and older self-identified as being from each of four ethnic groups: European American, African American, Korean American, or Mexican American (N = 800).
RESULTS
Korean Americans (47%) and Mexican Americans (65%) were significantly less likely than European Americans (87%) and African Americans (88%) to believe that a patient should be told the diagnosis of metastatic cancer. Korean Americans (35%) and Mexican Americans (48%) were less likely than African Americans (63%) and European Americans (69%) to believe that a patient should be told of a terminal prognosis and less likely to believe that the patient should make decisions about the use of life-supporting technology (28% and 41% vs 60% and 65%). Instead, Korean Americans and Mexican Americans tended to believe that the family should make decisions about the use of life support. On stepwise multiple logistic regression, ethnicity was the primary factor related to attitudes toward truth telling and patient decision making.
CONCLUSIONS
Korean-American and Mexican-American subjects were more likely to hold a family-centered model of medical decision making rather than the patient autonomy model favored by most of the African-American and European-American subjects. This finding suggests that physicians should ask their patients if they wish to receive information and make decisions or if they prefer that their families handle such matters.
Publication
Journal: Gut
September/27/1988
Abstract
Patterns of lower oesophageal sphincter (LOS) function associated with the onset of 644 reflux episodes were recorded and analysed in 67 patients referred for evaluation of gastro-oesophageal reflux (GOR). Patients were studied recumbent, for one hour before and four hours after a standard meal. Transient LOS relaxation was the most prevalent mechanism and overall accounted for 82% of reflux episodes. With increasing severity of oesophagitis, absent basal LOS pressure became a progressively more common mechanism, accounting for 23% of episodes in the patients with severe oesophagitis. Patients commonly exhibited more than one mechanism. The timing of most (69%) LOS relaxations associated with reflux was not compatible with triggering by swallowing. Prolonged transient LOS relaxations were associated with inhibition of oesophageal peristalsis suggesting that this response is produced by neural inhibition. This study suggests the primary importance of transient LOS relaxations as the cause of GOR across the spectrum of severity of reflux disease.
Publication
Journal: JAMA - Journal of the American Medical Association
April/15/2004
Abstract
BACKGROUND
Previous studies of surgical timing in patients with hip fracture have yielded conflicting findings on mortality and have not focused on functional outcomes.
OBJECTIVE
To examine the association of timing of surgical repair of hip fracture with function and other outcomes.
METHODS
Prospective cohort study including analyses matching cases of early (< or =24 hours) and late (>24 hours) surgery with propensity scores and excluding patients who might not be candidates for early surgery.
METHODS
Four hospitals in the New York City metropolitan area.
METHODS
A total of 1206 patients aged 50 years or older admitted with hip fracture over 29 months, ending December 1999.
METHODS
Function (using the Functional Independence Measure), survival, pain, and length of stay (LOS).
RESULTS
Of the patients treated with surgery (n = 1178), 33.8% had surgery within 24 hours. Earlier surgery was not associated with improved mortality (hazard ratio, 0.75; 95% confidence interval [CI], 0.52-1.08) or improved locomotion (difference of -0.04 points; 95% CI, -0.49 to 0.39). Earlier surgery was associated with fewer days of severe and very severe pain (difference of -0.22 days; 95% CI, -0.41 to -0.03) and shorter LOS by 1.94 days (P<.001), but postoperative pain and LOS after surgery did not differ. Analyses with propensity scores yielded similar results. When the cohort included only patients who were medically stable at admission and therefore eligible for early surgery, the results were unchanged except that early surgery was associated with fewer major complications (odds ratio, 0.26; 95% CI, 0.07-0.95).
CONCLUSIONS
Early surgery was not associated with improved function or mortality, but it was associated with reduced pain and LOS and probably major complications among patients medically stable at admission. Additional research is needed on whether functional outcomes may be improved. In the meantime, patients with hip fracture who are medically stable should receive early surgery when possible.
Publication
Journal: Journal of Mammary Gland Biology and Neoplasia
October/5/2010
Abstract
We review here the recently emerging relationship between epithelial-mesenchymal transition (EMT) and breast cancer stem cells (BCSC), and provide analyses of published data on human breast cancer cell lines, supporting their utility as a model for the EMT/BCSC state. Genome-wide transcriptional profiling of these cell lines has confirmed the existence of a subgroup with mesenchymal tendencies and enhanced invasive properties ('Basal B'/Mesenchymal), distinct from subgroups with either predominantly luminal ('Luminal') or mixed basal/luminal ('Basal A') features (Neve et al. Cancer Cell, 2006). A literature-derived EMT gene signature has shown specific enrichment within the Basal B subgroup of cell lines, consistent with their over-expression of various EMT transcriptional drivers. Basal B cell lines are found to resemble BCSC, being CD44(high)CD24(low). Moreover, gene products that distinguish Basal B from Basal A and Luminal cell lines (Basal B Discriminators) showed close concordance with those that define BCSC isolated from clinical material, as reported by Shipitsin et al. (Cancer Cell, 2007). CD24 mRNA levels varied across Basal B cell lines, correlating with other Basal B Discriminators. Many gene products correlating with CD24 status in Basal B cell lines were also differentially expressed in isolated BCSC. These findings confirm and extend the importance of the cellular product of the EMT with Basal B cell lines, and illustrate the value of analysing these cell lines for new leads that may improve breast cancer outcomes. Gene products specific to Basal B cell lines may serve as tools for the detection, quantification, and analysis of BCSC/EMT attributes.
Publication
Journal: Journal of Neuroscience
August/19/2007
Abstract
The vesicular monoamine transporter 2 (VMAT2; SLC18A2) is responsible for packaging dopamine into vesicles for subsequent release and has been suggested to serve a neuroprotective role in the dopamine system. Here, we show that mice that express approximately 5% of normal VMAT2 (VMAT2 LO) display age-associated nigrostriatal dopamine dysfunction that ultimately results in neurodegeneration. Elevated cysteinyl adducts to L-DOPA and DOPAC are seen early and are followed by increased striatal protein carbonyl and 3-nitrotyrosine formation. These changes were associated with decreased striatal dopamine and decreased expression of the dopamine transporter and tyrosine hydroxylase. Furthermore, we observed an increase in alpha-synuclein immunoreactivity and accumulation and neurodegeneration in the substantia nigra pars compacta in aged VMAT2 LO mice. Thus, VMAT2 LO animals display nigrostriatal degeneration that begins in the terminal fields and progresses to eventual loss of the cell bodies, alpha-synuclein accumulation, and an L-DOPA responsive behavioral deficit, replicating many of the key aspects of Parkinson's disease. These data suggest that mishandling of dopamine via reduced VMAT2 expression is, in and of itself, sufficient to cause dopamine-mediated toxicity and neurodegeneration in the nigrostriatal dopamine system. In addition, the altered dopamine homeostasis resulting from reduced VMAT2 function may be conducive to pathogenic mechanisms induced by genetic or environmental factors thought to be involved in Parkinson's disease.
Publication
Journal: Journal of Medical Entomology
December/4/2006
Abstract
Culex tarsalis Coquillett females were infected with the NY99 strain of West Nile virus (family Flaviviridae, genus Flavivirus, WNV) and then incubated under constant temperatures of 10-30 degrees C. At selected time intervals, transmission was attempted using an in vitro capillary tube assay. The median time from imbibing an infectious bloodmeal until infected females transmitted WNV (median extrinsic incubation period, EIP50) was estimated by probit analysis. By regressing the EIP rate (inverse of EIP50) as a function of temperature from 14 to 30 degrees C, the EIP was estimated to require 109 degree-days (DD) and the point of zero virus development (x-intercept) was estimated to be 14.3 degrees C. The resulting degree-day model showed that the NY99 WNV strain responded to temperature differently than a lineage II strain of WNV from South Africa and approximated our previous estimates for St. Louis encephalitis virus (family Flaviviridae, genus Flavivirus, SLEV). The invading NY99 WNV strain therefore required warm temperatures for efficient transmission. The time for completion of the EIP was estimated monthly from temperatures recorded at Coachella Valley, Los Angeles, and Kern County, California, during the 2004 epidemic year and related to the duration of the Cx. tarsalis gonotrophic cycle and measures of WNV activity. Enzootic WNV activity commenced after temperatures increased, the duration of the EIP decreased, and virus potentially was transmitted in two or less gonotrophic cycles. Temperatures in the United States during the epidemic summers of 2002-2004 indicated that WNV dispersal and resulting epicenters were linked closely to above-average summer temperatures.
Publication
Journal: Nature Medicine
May/22/2006
Abstract
Graft-versus-host disease (GVHD) is caused by alloreactive donor T cells that trigger host tissue injury. GVHD develops over weeks or months, but how this immune response is maintained over time is unknown. In mouse models of human GVHD, we identify a new subset of postmitotic CD44(lo)CD62L(hi)CD8(+) T cells that generate and sustain all allogeneic T-cell subsets in GVHD reactions, including central memory, effector memory and effector CD8(+) T cells, while self-renewing. These cells express Sca-1, CD122 and Bcl-2, and induce GVHD upon transfer into secondary recipients. The postmitotic CD44(lo)CD62L(hi)CD8(+) T cells persist throughout the course of GVHD, are generated in the initial phase in response to alloantigens and dendritic cells and require interleukin-15. Thus, their long life, ability to self-renew and multipotentiality define these cells as candidate memory stem cells. Memory stem cells will be important targets for understanding and influencing diverse chronic immune reactions, including GVHD.
Publication
Journal: Cancer Research
July/10/2011
Abstract
Epidemiologic studies have highlighted associations between the regular use of nonsteroidal anti-inflammatory drugs (NSAID) and reduced glioma risks in humans. Most NSAIDs function as COX-2 inhibitors that prevent production of prostaglandin E₂ (PGE₂). Because PGE₂ induces expansion of myeloid-derived suppressor cells (MDSC), we hypothesized that COX-2 blockade would suppress gliomagenesis by inhibiting MDSC development and accumulation in the tumor microenvironment (TME). In mouse models of glioma, treatment with the COX-2 inhibitors acetylsalicylic acid (ASA) or celecoxib inhibited systemic PGE₂ production and delayed glioma development. ASA treatment also reduced the MDSC-attracting chemokine CCL2 (C-C motif ligand 2) in the TME along with numbers of CD11b(+)Ly6G(hi)Ly6C(lo) granulocytic MDSCs in both the bone marrow and the TME. In support of this evidence that COX-2 blockade blocked systemic development of MDSCs and their CCL2-mediated accumulation in the TME, there were defects in these processes in glioma-bearing Cox2-deficient and Ccl2-deficient mice. Conversely, these mice or ASA-treated wild-type mice displayed enhanced expression of CXCL10 (C-X-C motif chemokine 10) and infiltration of cytotoxic T lymphocytes (CTL) in the TME, consistent with a relief of MDSC-mediated immunosuppression. Antibody-mediated depletion of MDSCs delayed glioma growth in association with an increase in CXCL10 and CTLs in the TME, underscoring a critical role for MDSCs in glioma development. Finally, Cxcl10-deficient mice exhibited reduced CTL infiltration of tumors, establishing that CXCL10 limited this pathway of immunosuppression. Taken together, our findings show that the COX-2 pathway promotes gliomagenesis by directly supporting systemic development of MDSCs and their accumulation in the TME, where they limit CTL infiltration.
Publication
Journal: American Journal of Public Health
April/13/1997
Abstract
OBJECTIVE
The role of competing priorities as a barrier to the utilization of physical health services was assessed in a subset (n = 363) of a probability sample of homeless adults in Los Angeles.
METHODS
Unadjusted odds of four measures of health services utilization were calculated for those with frequent difficulty in meeting their subsistence needs. These odds were then adjusted for a range of characteristics assumed to affect the utilization of health services among the homeless.
RESULTS
Before and after adjustment, those with frequent subsistence difficulty were less likely to have a regular source of care (odds ratio [OR] = 0.30, 95% confidence interval [CI] = 0.16, 0.53) and more likely to have gone without needed medical care (OR = 1.77, 95% CI = 1.04, 3.00). Subsistence difficulty had no impact on the likelihood of having an outpatient visit or having been hospitalized. Conclusions remained the same after adjustment.
CONCLUSIONS
Frequent subsistence difficulty appears to be an important nonfinancial barrier to the utilization of health services perceived as discretionary among homeless adults.
Publication
Journal: Nature Medicine
August/6/2017
Abstract
CD4(+) T cells that express the forkhead box P3 (FOXP3) transcription factor function as regulatory T (Treg) cells and hinder effective immune responses against cancer cells. Abundant Treg cell infiltration into tumors is associated with poor clinical outcomes in various types of cancers. However, the role of Treg cells is controversial in colorectal cancers (CRCs), in which FOXP3(+) T cell infiltration indicated better prognosis in some studies. Here we show that CRCs, which are commonly infiltrated by suppression-competent FOXP3(hi) Treg cells, can be classified into two types by the degree of additional infiltration of FOXP3(lo) nonsuppressive T cells. The latter, which are distinguished from FOXP3(+) Treg cells by non-expression of the naive T cell marker CD45RA and instability of FOXP3, secreted inflammatory cytokines. Indeed, CRCs with abundant infiltration of FOXP3(lo) T cells showed significantly better prognosis than those with predominantly FOXP3(hi) Treg cell infiltration. Development of such inflammatory FOXP3(lo) non-Treg cells may depend on secretion of interleukin (IL)-12 and transforming growth factor (TGF)-β by tissues and their presence was correlated with tumor invasion by intestinal bacteria, especially Fusobacterium nucleatum. Thus, functionally distinct subpopulations of tumor-infiltrating FOXP3(+) T cells contribute in opposing ways to determining CRC prognosis. Depletion of FOXP3(hi) Treg cells from tumor tissues, which would augment antitumor immunity, could thus be used as an effective treatment strategy for CRCs and other cancers, whereas strategies that locally increase the population of FOXP3(lo) non-Treg cells could be used to suppress or prevent tumor formation.
Publication
Journal: Journal of Experimental Medicine
March/9/2014
Abstract
IL-17A-expressing CD4(+) T cells (Th17 cells) are generally regarded as key effectors of autoimmune inflammation. However, not all Th17 cells are pro-inflammatory. Pathogenic Th17 cells that induce autoimmunity in mice are distinguished from nonpathogenic Th17 cells by a unique transcriptional signature, including high Il23r expression, and these cells require Il23r for their inflammatory function. In contrast, defining features of human pro-inflammatory Th17 cells are unknown. We show that pro-inflammatory human Th17 cells are restricted to a subset of CCR6(+)CXCR3(hi)CCR4(lo)CCR10(-)CD161(+) cells that transiently express c-Kit and stably express P-glycoprotein (P-gp)/multi-drug resistance type 1 (MDR1). In contrast to MDR1(-) Th1 or Th17 cells, MDR1(+) Th17 cells produce both Th17 (IL-17A, IL-17F, and IL-22) and Th1 (IFN-γ) cytokines upon TCR stimulation and do not express IL-10 or other anti-inflammatory molecules. These cells also display a transcriptional signature akin to pathogenic mouse Th17 cells and show heightened functional responses to IL-23 stimulation. In vivo, MDR1(+) Th17 cells are enriched and activated in the gut of Crohn's disease patients. Furthermore, MDR1(+) Th17 cells are refractory to several glucocorticoids used to treat clinical autoimmune disease. Thus, MDR1(+) Th17 cells may be important mediators of chronic inflammation, particularly in clinical settings of steroid resistant inflammatory disease.
Publication
Journal: Journal of the National Cancer Institute
May/9/2011
Abstract
BACKGROUND
Ipsilateral breast tumor recurrence (IBTR) is the most common failure event after lumpectomy for ductal carcinoma in situ (DCIS). We evaluated invasive IBTR (I-IBTR) and its influence on survival among participants in two National Surgical Adjuvant Breast and Bowel Project (NSABP) randomized trials for DCIS.
METHODS
In the NSABP B-17 trial (accrual period: October 1, 1985, to December 31, 1990), patients with localized DCIS were randomly assigned to the lumpectomy only (LO, n = 403) group or to the lumpectomy followed by radiotherapy (LRT, n = 410) group. In the NSABP B-24 double-blinded, placebo-controlled trial (accrual period: May 9, 1991, to April 13, 1994), all accrued patients were randomly assigned to LRT+ placebo, (n=900) or LRT + tamoxifen (LRT + TAM, n = 899). Endpoints included I-IBTR, DCIS-IBTR, contralateral breast cancers (CBC), overall and breast cancer-specific survival, and survival after I-IBTR. Median follow-up was 207 months for the B-17 trial (N = 813 patients) and 163 months for the B-24 trial (N = 1799 patients).
RESULTS
Of 490 IBTR events, 263 (53.7%) were invasive. Radiation reduced I-IBTR by 52% in the LRT group compared with LO (B-17, hazard ratio [HR] of risk of I-IBTR = 0.48, 95% confidence interval [CI] = 0.33 to 0.69, P < .001). LRT + TAM reduced I-IBTR by 32% compared with LRT + placebo (B-24, HR of risk of I-IBTR = 0.68, 95% CI = 0.49 to 0.95, P = .025). The 15-year cumulative incidence of I-IBTR was 19.4% for LO, 8.9% for LRT (B-17), 10.0% for LRT + placebo (B-24), and 8.5% for LRT + TAM. The 15-year cumulative incidence of all contralateral breast cancers was 10.3% for LO, 10.2% for LRT (B-17), 10.8% for LRT + placebo (B-24), and 7.3% for LRT + TAM. I-IBTR was associated with increased mortality risk (HR of death = 1.75, 95% CI = 1.45 to 2.96, P < .001), whereas recurrence of DCIS was not. Twenty-two of 39 deaths after I-IBTR were attributed to breast cancer. Among all patients (with or without I-IBTR), the 15-year cumulative incidence of breast cancer death was 3.1% for LO, 4.7% for LRT (B-17), 2.7% for LRT + placebo (B-24), and 2.3% for LRT + TAM.
CONCLUSIONS
Although I-IBTR increased the risk for breast cancer-related death, radiation therapy and tamoxifen reduced I-IBTR, and long-term prognosis remained excellent after breast-conserving surgery for DCIS.
Publication
Journal: Blood
March/25/2010
Abstract
Tumor-infiltrating myeloid cells (TIMs) support tumor growth by promoting angiogenesis and suppressing antitumor immune responses. CSF-1 receptor (CSF1R) signaling is important for the recruitment of CD11b(+)F4/80(+) tumor-associated macrophages (TAMs) and contributes to myeloid cell-mediated angiogenesis. However, the impact of the CSF1R signaling pathway on other TIM subsets, including CD11b(+)Gr-1(+) myeloid-derived suppressor cells (MDSCs), is unknown. Tumor-infiltrating MDSCs have also been shown to contribute to tumor angiogenesis and have recently been implicated in tumor resistance to antiangiogenic therapy, yet their precise involvement in these processes is not well understood. Here, we use the selective pharmacologic inhibitor of CSF1R signaling, GW2580, to demonstrate that CSF-1 regulates the tumor recruitment of CD11b(+)Gr-1(lo)Ly6C(hi) mononuclear MDSCs. Targeting these TIM subsets inhibits tumor angiogenesis associated with reduced expression of proangiogenic and immunosuppressive genes. Combination therapy using GW2580 with an anti-VEGFR-2 antibody synergistically suppresses tumor growth and severely impairs tumor angiogenesis along with reverting at least one TIM-mediated antiangiogenic compensatory mechanism involving MMP-9. These data highlight the importance of CSF1R signaling in the recruitment and function of distinct TIM subsets, including MDSCs, and validate the benefits of targeting CSF1R signaling in combination with antiangiogenic drugs for the treatment of solid cancers.
Publication
Journal: Journal of Experimental Medicine
March/25/2009
Abstract
Memory T cells exhibit superior responses to pathogens and tumors compared with their naive counterparts. Memory is typically generated via an immune response to a foreign antigen, but functional memory T cells can also be produced from naive cells by homeostatic mechanisms. Using a recently developed method, we studied CD8 T cells, which are specific for model (ovalbumin) and viral (HSV, vaccinia) antigens, in unimmunized mice and found a subpopulation bearing markers of memory cells. Based on their phenotypic markers and by their presence in germ-free mice, these preexisting memory-like CD44(hi) CD8 T cells are likely to arise via physiological homeostatic proliferation rather than a response to environmental microbes. These antigen-inexperienced memory phenotype CD8 T cells display several functions that distinguish them from their CD44(lo) counterparts, including a rapid initiation of proliferation after T cell stimulation and rapid IFN-gamma production after exposure to proinflammatory cytokines. Collectively, these data indicate that the unprimed antigen-specific CD8 T cell repertoire contains antigen-inexperienced cells that display phenotypic and functional traits of memory cells.
Publication
Journal: The Journal of trauma
June/18/2003
Abstract
BACKGROUND
We have previously shown that blood transfusion in the first 24 hours is an independent predictor of mortality, intensive care unit (ICU) admission, and increased ICU length of stay in the acute trauma setting when controlling for Injury Severity Score, Glasgow Coma Scale score, and age. Indices of shock such as base deficit, serum lactate level, and admission hemodynamic status (systolic blood pressure, heart rate) and admission hematocrit were considered potential confounding variables in that study. The objectives of this study were to evaluate admission anemia and blood transfusion within the first 24 hours as independent predictors of mortality, ICU admission, ICU length of stay (LOS), and hospital LOS, with serum lactate level, base deficit, and shock index (heart rate/systolic blood pressure) as covariates.
METHODS
Prospective data were collected on 15,534 patients admitted to a Level I trauma center over a 3-year period (1998-2000) and stratified by age, gender, race, Glasgow Coma Scale score, and Injury Severity Score. Admission anemia and blood transfusion were assessed as independent predictors of mortality, ICU admission, ICU LOS, and hospital LOS by logistic regression analysis, with base deficit, serum lactate, and shock index as covariates.
RESULTS
Blood transfusion was a strong independent predictor of mortality (odds ratio [OR], 2.83; 95% confidence interval [CI], 1.82-4.40; p < 0.001), ICU admission (OR, 3.27; 95% CI, 2.69-3.99; p < 0.001), ICU LOS (p < 0.001), and hospital LOS (Coef, 4.37; 95% CI, 2.79-5.94; p < 0.001) when stratified by indices of shock (base deficit, serum lactate, shock index, and anemia). Patients who underwent blood transfusion were almost three times more likely to die and greater than three times more likely to be admitted to the ICU. Admission anemia (hematocrit < 36%) was an independent predictor of ICU admission (p = 0.008), ICU LOS (p = 0.012), and hospital LOS (p < 0.001).
CONCLUSIONS
Blood transfusion is confirmed as an independent predictor of mortality, ICU admission, ICU LOS, and hospital LOS in trauma after controlling for severity of shock by admission base deficit, lactate, shock index, and anemia. The use of other hemoglobin-based oxygen-carrying resuscitation fluids (such as human or bovine hemoglobin substitutes) in the acute postinjury period warrants further investigation.
Publication
Journal: Annals of Internal Medicine
May/5/1996
Abstract
OBJECTIVE
To identify physician and practice characteristics associated with a physician's propensity to involve patients in diagnostic and treatment decisions, or participatory decision-making style.
METHODS
A representative cross-sectional sample of patients participating in the Medical Outcomes Study characterized each physician's style by using a self-reported questionnaire. A single averaged style score was generated for each physician. Style scores were compared among physicians who differed in age, sex, minority status, specialty, primary care training or training in interviewing skills, satisfaction with professional autonomy, and practice volume.
METHODS
Solo practices, multispecialty groups, and health maintenance organizations in Boston, Chicago, and Los Angeles.
METHODS
7730 patients sampled over 9 days from the practices of 300 physicians. Physicians were practicing general internal medicine, family medicine, cardiology, and endocrinology.
METHODS
Participatory decision-making style was measured using a three-item scale on a questionnaire that was completed by patients after their office visit. Physician and practice characteristics were reported by physicians on self-administered questionnaires.
RESULTS
Among patients of physicians who were rated in the lowest (least participatory) quartile, one third changed physicians in the following year; among patients of physicians who were rated in the highest quartile, only 15% changed physicians. Higher scores were associated with greater patient satisfaction. Physicians who had had primary care training or training in interviewing skills scored higher than those without such training. Physicians in higher-volume practices were rated as less participatory than those in lower-volume practices. Physicians who were satisfied with their level of professional autonomy were rates as more participatory than those who were dissatisfied.
CONCLUSIONS
Participatory decision-making style is influenced by physicians' background, training, practice volume, and professional autonomy. Because participatory decision-making style is related to patient satisfaction and loyalty to the physician, cost-containment strategies that reduce time with patients and decrease physician autonomy may result in suboptimal patient outcomes.
Publication
Journal: Annals of Surgery
September/25/2008
Abstract
OBJECTIVE
To compare perioperative outcomes of laparoscopic left-sided pancreatectomy (LLP) with traditional open left-sided pancreatectomy (OLP) in a multicenter experience.
BACKGROUND
LLP is being performed more commonly with limited data comparing results with outcomes from OLP.
METHODS
Data from 8 centers were combined for all cases performed between 2002-2006. OLP and LLP cohorts were matched by age, American Society of Anesthesiologists, resected pancreas length, tumor size, and diagnosis. Multivariate analysis was performed using binary logistic regression.
RESULTS
Six hundred sixty-seven LPs were performed, with 159 (24%) attempted laparoscopically. Indications were solid lesion in 307 (46%), cystic in 295 (44%), and pancreatitis in 65 (10%) cases. Positive margins occurred in 51 (8%) cases, 335 (50%) had complications, and significant leaks occurred in 108 (16%). Conversion to OLP occurred in 20 (13%) of the LLPs. In the matched comparison, 200 OLPs were compared with 142 LLPs. There were no differences in positive margin rates (8% vs. 7%, P = 0.8), operative times (216 vs. 230 minutes, P = 0.3), or leak rates (18% vs. 11%, P = 0.1). LLP patients had lower average blood loss (357 vs. 588 mL, P < 0.01), fewer complications (40% vs. 57%, P < 0.01), and shorter hospital stays (5.9 vs. 9.0 days, P < 0.01). By MVA, LLP was an independent factor for shorter hospital stay (P < 0.01, odds ratio 0.33, 95% confidence interval 0.19-0.56).
CONCLUSIONS
In selected patients, LLP is associated with less morbidity and shorter LOS than OLP. Pancreatic fistula rates are similar for OLP and LLP. LLP is appropriate for selected patients with left-sided pancreatic pathology.
Publication
Journal: New England Journal of Medicine
February/12/1997
Abstract
BACKGROUND
After the age of 60, isolated cardiac amyloidosis is four times more common among blacks than whites in the United States; 3.9 percent of blacks are heterozygous for an amyloidogenic allele of the normal serum carrier protein transthyretin in which isoleucine is substituted for valine at position 122 (Ile 122). We hypothesized that the high prevalence of transthyretin Ile 122 is at least partially responsible for the increased frequency of senile cardiac amyloidosis among blacks.
METHODS
Paraffin blocks of cardiac tissue were obtained from an earlier study of 52,370 autopsies in Los Angeles and were examined by immunohistochemical and DNA analyses. Samples were available from 32 of 55 blacks and 20 of 78 whites over 60 years of age with isolated cardiac amyloidosis and from two control groups (228 cases).
RESULTS
Transthyretin amyloidosis was identified in 31 of the 32 cardiac-tissue samples from the black patients and in 19 of the 20 samples from the white patients. Six of the 26 analyzable DNA samples (23 percent) from the black patients and none of the 19 samples from the white patients were heterozygous for the Ile 122 variant. Four of 125 DNA samples obtained at autopsy (3.2 percent) from a second, more recent, age-matched cohort of blacks without amyloidosis at the same institution were heterozygous for the transthyretin Ile 122 allele. On reexamination the cardiac tissue from these four patients contained small amounts of amyloid not detected at the initial autopsies. All subjects with the Ile 122 variant had ventricular amyloid.
CONCLUSIONS
The assessment of elderly black patients with unexplained heart disease should include a consideration of transthyretin amyloidosis, particularly that related to the Ile 122 allele.
Publication
Journal: Cell
July/31/2013
Abstract
Unique among leukocytes, neutrophils follow daily cycles of release from and migration back into the bone marrow, where they are eliminated. Because removal of dying cells generates homeostatic signals, we explored whether neutrophil elimination triggers circadian events in the steady state. Here, we report that the homeostatic clearance of neutrophils provides cues that modulate the physiology of the bone marrow. We identify a population of CD62L(LO) CXCR4(HI) neutrophils that have "aged" in the circulation and are eliminated at the end of the resting period in mice. Aged neutrophils infiltrate the bone marrow and promote reductions in the size and function of the hematopoietic niche. Modulation of the niche depends on macrophages and activation of cholesterol-sensing nuclear receptors and is essential for the rhythmic egress of hematopoietic progenitors into the circulation. Our results unveil a process that synchronizes immune and hematopoietic rhythms and expand the ascribed functions of neutrophils beyond inflammation. PAPERFLICK:
Publication
Journal: Development (Cambridge)
November/11/2003
Abstract
The platelet glycoprotein IIb (alpha(IIb); CD41) constitutes the alpha subunit of a highly expressed platelet surface integrin protein. We demonstrate that CD41 serves as the earliest marker of primitive erythroid progenitor cells in the embryonic day 7 (E7.0) yolk sac and high-level expression identifies essentially all E8.25 yolk sac definitive hematopoietic progenitors. Some definitive hematopoietic progenitor cells in the fetal liver and bone marrow also express CD41. Hematopoietic stem cell competitive repopulating ability is present in CD41(dim) and CD41(lo/-) cells isolated from bone marrow and fetal liver cells, however, activity is enriched in the CD41(lo/-) cells. CD41(bright) yolk sac definitive progenitor cells co-express CD61 and bind fibrinogen, demonstrating receptor function. Thus, CD41 expression marks the onset of primitive and definitive hematopoiesis in the murine embryo and persists as a marker of some stem and progenitor cell populations in the fetal liver and adult marrow, suggesting novel roles for this integrin.
Publication
Journal: Circulation
September/29/2002
Abstract
BACKGROUND
The need for accurate risk stratification is heightened by the expanding indications for the implantable cardioverter defibrillator. The Multicenter Automatic Defibrillator Implantation Trial (MADIT) focused interest on patients with both depressed left ventricular ejection fraction (LVEF) and the presence of nonsustained ventricular tachycardia (NSVT). Meanwhile, the prospective study Autonomic Tone and Reflexes After Myocardial Infarctio (ATRAMI) demonstrated that markers of reduced vagal activity, such as depressed baroreflex sensitivity (BRS) an heart rate variability (HRV), are strong predictors of cardiac mortality after myocardial infarction.
RESULTS
We analyzed 1071 ATRAMI patients after myocardial infarction who had data on LVEF, 24-hour ECG recording, and BRS. During follow-up (21 +/- 8 months), 43 patients experienced cardiac death, 5 patients had episodes of sustained VT, and 30 patients experienced sudden death and/or sustained VT. NSVT, depressed BRS, or HRV were all significantly and independently associated with increased mortality. The combination of all 3 risk factor increased the risk of death by 22x. Among patients with LVEF<35%, despite the absence of NSVT, depressed BRS predicted higher mortality (18% versus 4.6%, P = 0.01). This is a clinically important finding because this grou constitutes 25% of all patients with depressed LVEF. For both cardiac and arrhythmic mortality, the sensitivity of lo BRS was higher than that of NSVT and HRV CONCLUSIONS: BRS and HRV contribute importantly and additionally to risk stratification. Particularly when LVEF is depressed, the analysis of BRS identifies a large number of patients at high risk for cardiac and arrhythmic mortalit who might benefit from implantable cardioverter defibrillator therapy without disproportionately increasing the number of false-positives.
Publication
Journal: Blood
October/5/2004
Abstract
Human hematopoietic stem cells (HSCs) are commonly purified by the expression of cell surface markers such as CD34. Because cell phenotype can be altered by cell cycle progression or ex vivo culture, purification on the basis of conserved stem cell function may represent a more reliable way to isolate various stem cell populations. We have purified primitive HSCs from human umbilical cord blood (UCB) by lineage depletion (Lin(-)) followed by selection of cells with high aldehyde dehydrogenase (ALDH) activity. ALDH(hi)Lin(-) cells contained 22.6% +/- 3.0% of the Lin(-) population and highly coexpressed primitive HSC phenotypes (CD34(+) CD38(-) and CD34(+)CD133(+)). In vitro hematopoietic progenitor function was enriched in the ALDH(hi)Lin(-) population, compared with ALDH(lo)Lin(-) cells. Multilineage human hematopoietic repopulation was observed exclusively after transplantation of ALDH(hi)Lin(-) cells. Direct comparison of repopulation with use of the nonobese diabetic/severe combined immunodeficient (NOD/SCID) and NOD/SCID beta2 microglobulin (beta2M) null models demonstrated that 10-fold greater numbers of ALDH(hi)-Lin(-) cells were needed to engraft the NOD/SCID mouse as compared with the more permissive NOD/SCID beta2M null mouse, suggesting that the ALDH(hi)Lin(-) population contained committed progenitors as well as primitive repopulating cells. Cell fractionation according to lineage depletion and ALDH activity provides a viable and prospective purification of HSCs on the basis of cell function rather than cell surface phenotype.
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