OBJECTIVE

To analyse whether the beneficial effects of methotrexate in rheumatoid arthritis (RA) could be due to inhibition of inflammatory cytokine production.

METHODS

Cytokine production was studied using whole blood (WB) and mononuclear cells (MNC) of healthy volunteers and RA patients. Cultures were stimulated with either bacterial products such as lipo-oligosaccharide (LOS) or Staphylococcus aureus Cowan I (SAC) to activate monocytes or with monoclonal antibodies to CD3 and CD28 to induce polyclonal T-cell activation. We analysed the effect of methotrexate on cytokine production in these systems.

RESULTS

We showed that methotrexate inhibits production of cytokines induced by T-cell activation. Among the cytokines inhibited were interleukin 4 (IL-4), IL-13, IFN gamma, tumour necrosis factor-alpha (TNF alpha) and granulocyte-macrophage colony-stimulating factor. Inhibition was seen at concentrations easily achieved in plasma of RA patients taking the drug. IL-8 production was hardly influenced by methotrexate. Furthermore, inhibition was dependent on the stimulus; IL-6, IL-8, IL-1 beta and TNF alpha production induced by LOS or SAC was only slightly decreased by methotrexate. The addition of folinic acid or thymidine and hypoxanthine reversed the inhibitory effects of methotrexate on cytokine production. Concentrations of methotrexate required for inhibition varied between donors. Oral intake of 10 mg methotrexate by RA patients led to marked inhibition of cytokine production in blood drawn after 2 h.

CONCLUSIONS

Methotrexate turns out to be an efficient inhibitor of cytokine production induced by T-cell activation in freshly drawn blood. This is due to inhibition of the de novo synthesis of purines and pyrimidines. Cytokines produced by monocytes are hardly affected by methotrexate.

OBJECTIVE

To assess the efficacy of idebenone on neurological function in patients with Friedreich ataxia.

METHODS

Randomized, double-blind, placebo-controlled intervention trial.

METHODS

Children's Hospital of Philadelphia and the University of California at Los Angeles.

METHODS

Seventy ambulatory pediatric patients (age, 8-18 years) with a baseline International Cooperative Ataxia Rating Scale (ICARS) score of 10 to 54.

METHODS

Participants were randomized into 1 of 3 treatment arms: 450 or 900 mg of idebenone per day (in those with a body weight < or = or >45 kg, respectively; n = 22); 1350 or 2250 mg of idebenone per day (n = 24); or placebo (n = 24).

METHODS

Mean change from baseline to week 24 in ICARS score was the primary efficacy variable. Mean change in Friedreich Ataxia Rating Scale (FARS) score, performance measures, and activities of daily living were the secondary efficacy variables.

RESULTS

Patients who received idebenone improved by 2.5 points on mean ICARS score compared with baseline, while patients in the placebo group improved by 1.3 points. Patients who took idebenone also improved by 1.6 points on the FARS, while patients taking placebo declined by 0.6 points. For both end points, the difference between the idebenone and placebo groups was not statistically different.

CONCLUSIONS

Idebenone did not significantly alter neurological function in Friedreich ataxia during the 6-month study. Larger studies of longer duration may be needed to assess the therapeutic potential of drug candidates on neurological function in Friedreich ataxia. Trial Registration clinicaltrials.gov Identifier: NCT00537680.

Cryptococcus gattii infections in southern California have been reported in patients with HIV/AIDS. In this study, we examined the molecular epidemiology, population structure, and virulence attributes of isolates collected from HIV/AIDS patients in Los Angeles County, California. We show that these isolates consist almost exclusively of VGIII molecular type, in contrast to the VGII molecular type isolates causing the North American Pacific Northwest outbreak. The global VGIII population structure can be divided into two molecular groups, VGIIIa and VGIIIb. Isolates from the Californian patients are virulent in murine and macrophage models of infection, with VGIIIa significantly more virulent than VGIIIb. Several VGIII isolates are highly fertile and produce abundant sexual spores that may serve as infectious propagules. The a and α VGIII MAT locus alleles are largely syntenic with limited rearrangements compared to the known VGI (a/α) and VGII (α) MAT loci, but each has unique characteristics including a distinct deletion flanking the 5' VGIII MATa alleles and the α allele is more heterogeneous than the a allele. Our studies indicate that C. gattii VGIII is endemic in southern California, with other isolates originating from the neighboring regions of Mexico, and in rarer cases from Oregon and Washington state. Given that >1,000,000 cases of cryptococcal infection and >620,000 attributable mortalities occur annually in the context of the global AIDS pandemic, our findings suggest a significant burden of C. gattii may be unrecognized, with potential prognostic and therapeutic implications. These results signify the need to classify pathogenic Cryptococcus cases and highlight possible host differences among the C. gattii molecular types influencing infection of immunocompetent (VGI/VGII) vs. immunocompromised (VGIII/VGIV) hosts.

OBJECTIVE

Sarcopenia and changes in body composition following neoadjuvant chemotherapy (NAC) may affect clinical outcome. We assessed the associations between CT body composition changes following NAC and outcomes in oesophageal cancer.

METHODS

A total of 35 patients who received NAC followed by oesophagectomy, and underwent CT assessment pre- and post-NAC were included. Fat mass (FM), fat-free mass (FFM), subcutaneous fat to muscle ratio (FMR) and visceral to subcutaneous adipose tissue ratio (VA/SA) were derived from CT. Changes in FM, FFM, FMR, VA/SA and sarcopenia were correlated to chemotherapy dose reductions, postoperative complications, length of hospital stay (LOS), circumferential resection margin (CRM), pathological chemotherapy response, disease-free survival (DFS) and overall survival (OS).

RESULTS

Nine (26 %) patients were sarcopenic before NAC and this increased to 15 (43 %) after NAC. Average weight loss was 3.7 % ± 6.4 (SD) in comparison to FM index (-1.2 ± 4.2), FFM index (-4.6 ± 6.8), FMR (-1.2 ± 24.3) and VA/SA (-62.3 ± 12.7). Changes in FM index (p = 0.022), FMR (p = 0.028), VA/SA (p = 0.024) and weight (p = 0.007) were significant univariable factors for CRM status. There was no significant association between changes in body composition and survival.

CONCLUSIONS

Loss of FM, differential loss of VA/SA and skeletal muscle were associated with risk of CRM positivity.

CONCLUSIONS

• Changes in CT body composition occur after neoadjuvant chemotherapy in oesophageal cancer. • Sarcopenia was more prevalent after neoadjuvant chemotherapy. • Fat mass, fat-free mass and weight decreased after neoadjuvant chemotherapy. • Changes in body composition were associated with CRM positivity. • Changes in body composition did not affect perioperative complications and survival.

BACKGROUND

Determining anatomic sites and circumstances under which a fracture may be a consequence of osteoporosis is a topic of ongoing debate and controversy that is important to both clinicians and researchers.

METHODS

We conducted a systematic literature review and generated an evidence report on fracture risk based on specific anatomic bone sites and fracture diagnosis codes. Using the Research and Development/University of California at Los Angeles appropriateness process, we convened a multidisciplinary panel of 11 experts who rated fractures according to their likelihood of being because of osteoporosis based on the evidence report. Fracture sites (as determined by International Classification of Diseases Clinical Modification codes) were stratified by four clinical risk factor categories based on age, sex, race/ethnicity (African American and Caucasian), and presence or absence of trauma.

RESULTS

Consistent with current clinical experience, the fractures rated most likely because of osteoporosis were the femoral neck, pathologic fractures of the vertebrae, and lumbar and thoracic vertebral fractures. The fractures rated least likely because of osteoporosis were open proximal humerus fractures, skull, and facial bones. The expert panel rated open fractures of the arm (except proximal humerus) and fractures of the tibia/fibula, patella, ribs, and sacrum as being highly likely because of osteoporosis in older Caucasian women but a lower likelihood in younger African American men.

CONCLUSIONS

Osteoporosis attribution scores for all fracture sites were determined by a multidisciplinary expert panel to provide an evidence-based continuum of the likelihood of a fracture being associated with osteoporosis.

OBJECTIVE

To describe gut colonization in preterm infants using standard culture and 16S gene rRNA profiling, exploring differences in healthy infants and those who developed NEC/late onset sepsis (LOS).

METHODS

Ninety-nine stools from 38 infants of median 27-week gestation were cultured; 44 stools from 27 infants had their microbial profiles determined by 16S. Ordination analyses explored effects of patient variables on gut communities.

RESULTS

Standard microbiological culture identified a mean of two organisms (range 0-7), DGGE 12 (range 3-18) per patient. Enterococcus faecalis and coagulase negative staphylococci (CONS) were most common by culture (40% and 39% of specimens). Meconium was not sterile. No fungi were cultured. Bacterial community structures in infants with NEC and LOS differed from healthy infants. Infants who developed NEC carried more CONS (45% vs 30%) and less Enterococcus faecalis (31% vs 57%). 16S identified Enterobacter and Staphylococcus presence associated with NEC/LOS, respectively.

CONCLUSIONS

Important differences were found in the gut microbiota of preterm infants who develop NEC/LOS. The relationship of these changes to current practices in neonatal intensive care requires further exploration.

BACKGROUND

Epidemiologic studies suggest that populations that consume large amounts of dietary fat are at greater risk for prostate carcinoma. Arachidonic acid and its precursor, linoleic acid, are major ingredients of animal fats and many vegetable oils that are used in the regions where prostate carcinoma is prevalent. The metabolism of arachidonic acid by either the cyclooxygenase pathway or the lipoxygenase pathway generates eicosanoids, which have been implicated in the pathogenesis of a variety of human diseases, including cancer, and are now believed to play important roles in tumor promotion, progression, and metastasis. Studying these pathways in specimens from patients with prostate carcinoma, the authors recently demonstrated the overexpression of cyclooxygenase-2 in prostate adenocarcinoma. In the current study, the authors report the overexpression of lipoxygenase-5 (5-LO) in samples from patients with prostate adenocarcinoma.

METHODS

Employing 22 pair-matched benign and malignant tissue samples that were obtained from the same patients with prostate carcinoma, the expression of 5-LO was determined using reverse transcriptase-polymerase chain reaction, immunoblotting, and immunohistochemistry and by measuring the levels of 5-hydroxyeicosatetraenoic acid (5-HETE) by radioimmunoassay.

RESULTS

The mean level of 5-LO mRNA was six-fold greater (P < 0.001) in malignant tissue compared with benign tissue. The immunoblot analysis demonstrated that, compared with benign tissue, 5-LO protein was overexpressed in 16 of 22 samples examined and was 2.6 fold greater (P < 0.001) in malignant tissue. Immunohistochemical studies further verified 5-LO up-regulation in malignant tissue that was not present in benign tissue. The levels of 5-HETE, which is a metabolic product of arachidonic acid, was found to be 2.2-fold greater (P < 0.001) in malignant tumor tissue compared with benign tissue.

CONCLUSIONS

To the authors' knowledge, this is the first in vivo study showing overexpression of 5-LO in patients with prostate carcinoma. This study suggests that inhibitors of arachidonic acid pathway in general and selective 5-LO inhibitors in particular may be useful for prevention or therapy in patients with prostate carcinoma.

BACKGROUND

Cardiac troponins are emerging as important prognostic markers in chronic cardiovascular conditions like stable coronary artery disease or chronic heart failure (HF). Less is known about the relation between serial measurements of high-sensitivity cardiac troponin T (hs-cTnT) and future events in HF. We determined the association between changes over time in hs-cTnT and outcome in patients with chronic HF.

RESULTS

We analyzed 5284 patients with chronic HF from 2 independent randomized clinical trials, the Valsartan Heart Failure Trial (Val-HeFT) (n=4053) and the Gruppo Italiano per lo Studio della Sopravvivenza nell'Insufficienza Cardiaca-Heart Failure (GISSI-HF) trial (n=1231). hs-cTnT was measured at randomization and after 3 months (GISSI-HF) or 4 months of follow-up (Val-HeFT). The association between changes over time of hs-cTnT and various outcomes was tested in multivariable models. In both studies, increases in hs-cTnT levels over time were associated with age, diabetes mellitus, worsening of renal function (reduction in estimated glomerular filtration rate), and baseline and increases in N-terminal pro-brain natriuretic peptide concentrations. Increases in hs-cTnT concentrations were associated with all-cause mortality (incidence rates, 8.19 [7.51-8.88] and 6.79 [5.98-7.61] per 100 person-years in Val-HeFT and GISSI-HF, respectively, with hazard ratios [95% confidence intervals] of 1.59 [1.39-1.82] and 1.88 [1.50-2.35]) after adjustment for conventional risk factors and baseline levels of hs-cTnT and N-terminal pro-brain natriuretic peptide. Changes in hs-cTnT concentration modestly improved prognostic discrimination beyond baseline values for fatal outcomes only.

CONCLUSIONS

Despite very low circulating concentrations, changes in hs-cTnT concentrations over time are robust predictors of future cardiovascular events in patients with chronic HF but add limited prognostic discrimination.

BACKGROUND

http://www.clinicaltrials.gov. Unique identifier: NCT00336336.

OBJECTIVE

In the present study, the effect of previous detoxifications on prefrontal function and decision making was examined in alcohol-dependent patients. Further, we examined whether the length of abstinence affects cognitive function.

METHODS

Forty-eight alcohol-dependent patients were recruited from an inpatient detoxification treatment facility and cognitive function was compared to a control group of 36 healthy controls. The patient population was then divided into a group of patients with less than two previous detoxifications (LO-detox group, n = 27) and a group of patients with two or more previous detoxifications (HI-detox group, n = 21) and cognitive function was compared. In addition, cognitive function of recently (i.e. less than 16 days; median split) and longer abstinent patients was compared. We assessed prefrontal function, memory function and intelligence.

RESULTS

Alcoholics, when compared to healthy controls, performed worse with regard to the performance index Attention/Executive function. Cognitive impairment in these tasks was pronounced in recently abstinent patients. We found no significant differences between HI-detox and LO-detox patients with regard to the Attention/Executive function. However, in the IOWA gambling Task, the HI-detox group seemed to be less able to learn to choose cards from the more advantageous decks over time.

CONCLUSIONS

Our results provide additional evidence for cognitive impairment of alcohol-dependent patients with regard to tasks sensitive to frontal lobe function and underline the importance of abstinence for these impairments to recover. We found only little evidence for the impairing effects of repeated withdrawal on prefrontal function and we suggest that executive function is affected earlier in dependence.

Molecular mimicry between lipooligosaccharides (LOS) of Campylobacter jejuni and gangliosides in peripheral nerves plays a crucial role in the pathogenesis of C. jejuni-related Guillain-Barré syndrome (GBS). We have analyzed the LOS outer core structures of 26 C. jejuni strains associated with GBS and its variant, Miller Fisher syndrome (MFS), by capillary electrophoresis coupled with electrospray ionization mass spectrometry. Sixteen out of 22 (73%) GBS-associated and all 4 (100%) MFS-associated strains expressed LOS with ganglioside mimics. GM1a was the most prevalent ganglioside mimic in GBS-associated strains (10/22, 45%), and in eight of these strains, GM1a was found in combination with GD1a mimics. All seven strains isolated from patients with ophthalmoplegia (GBS or MFS) expressed disialylated (GD3 or GD1c) mimics. Three out of 22 GBS-associated strains (14%) did not express sialylated ganglioside mimics because their LOS locus lacked the genes necessary for sialylation. Three other strains (14%) did not express ganglioside mimics because of frameshift mutations in either the cstII sialyltransferase gene or the cgtB galactosyltransferase gene. It is not possible to determine if these mutations were already present during C. jejuni infection. This is the first report in which mass spectrometry combined with DNA sequence data were used to infer the LOS outer core structures of a large number of neuropathy-associated C. jejuni strains. We conclude that molecular mimicry between gangliosides and C. jejuni LOS is the presumable pathogenic mechanism in most cases of C. jejuni-related GBS. However, our findings suggest that in some cases, other mechanisms may play a role. Further examination of the disease etiology in these patients is mandatory.

BACKGROUND

Laparoscopic liver resection has thus far not gained widespread acceptance among liver surgeons. Valid questions remain regarding the relative clinical superiority of the laparoscopic approach as well as whether laparoscopic hepatectomy carries any economic benefit compared with open liver surgery.

OBJECTIVE

The aim of this work is to compare the clinical and economic impact of laparoscopic versus open left lateral sectionectomy (LLS).

METHODS

Between May 2002 and July 2008, 44 laparoscopic LLS and 29 open LLS were included in the analysis. Deviation-based cost modeling (DBCM) was utilized to compare the combined clinical and economic impact of the open and laparoscopic approaches.

RESULTS

The laparoscopic approach compared favorably with the open approach from both a clinical and economic standpoint. Not only was the median length of stay (LOS) shorter by 2 days in the laparoscopic group (3 versus 5 days, respectively, P = 0.001), but the laparoscopic cohort also benefited from a significant reduction in postoperative morbidity (P = 0.001). Because the groups differed significantly in age and ratio of benign to malignant disease, a subgroup analysis limited to patients with malignant disease was undertaken. The same reduction in LOS and postoperative morbidity was evident within the malignant subgroup undergoing laparoscopic LLS (P = 0.003). The economic impact of the laparoscopic approach was noteworthy, with the laparoscopic approach US$1,527-2,939 more cost efficient per patient compared with the open technique.

CONCLUSIONS

Our study seems not only to corroborate the safety and clinical benefit of the laparoscopic approach but also suggests a fiscally important cost advantage for the minimally invasive approach.

OBJECTIVE

To determine the prevalence of and risk factors for gastro-oesophageal reflux disease (GORD), reflux oesophagitis and non-erosive reflux disease (NERD) amongst Malaysian patients undergoing upper gastrointestinal endoscopic examination.

METHODS

A cross-sectional study on consecutive patients with dyspepsia undergoing upper gastrointestinal endoscopy.

METHODS

A large general hospital in Kuala Lumpur, Malaysia.

METHODS

Consecutive patients undergoing endoscopy for upper abdominal discomfort were examined for the presence of reflux oesophagitis, hiatus hernia and Barrett's oesophagus. The diagnosis and classification of reflux oesophagitis was based on the Los Angeles classification. Patients with predominant symptoms of heartburn or acid regurgitation of at least one per month for the past 6 months in the absence of reflux oesophagitis were diagnosed as having NERD. The prevalence of GORD, reflux oesophagitis and NERD were analysed in relation to age, gender, race, body mass index (BMI), presence of hiatus hernia, Helicobacter pylori status, alcohol intake, smoking and level of education.

RESULTS

One thousand patients were studied prospectively. Three hundred and eighty-eight patients (38.8%) were diagnosed as having GORD based on either predominant symptoms of heartburn and acid regurgitation and/or findings of reflux oesophagitis. One hundred and thirty-four patients (13.4%) had endoscopic evidence of reflux oesophagitis. Two hundred and fifty-four (65.5%) were diagnosed as having NERD. Hiatus hernia was found in 6.7% and Barrett's oesophagus in 2% of patients. Of our patients with reflux oesophagitis 20.1% had grade C and D oesophagitis. No patients had strictures. Following logistic regression analysis, the independent risk factors for GORD were Indian race (odds ratio (OR), 3.25; 95% confidence interval (CI), 2.38-4.45), Malay race (OR, 1.67; 95% CI, 1.16-2.38), BMI>> 25 (OR, 1.41; 95% CI, 1.04-1.92), presence of hiatus hernia (OR, 4.21; 95% CI, 2.41-7.36), alcohol consumption (OR, 2.42; 95% CI, 1.11-5.23) and high education level (OR, 1.52; 95% CI, 1.02-2.26). For reflux oesophagitis independent the risk factors male gender (OR, 1.64; 95% CI, 1.08-2.49), Indian race (OR, 3.25; 95% CI, 2.05-5.17), presence of hiatus hernia (OR, 11.67; 95% CI, 6.40-21.26) and alcohol consumption (OR, 3.22; 95% CI, 1.26-8.22). For NERD the independent risk factors were Indian race (OR, 3.45; 95% CI, 2.42-4.92), Malay race (OR, 1.80; 95% CI, 1.20-2.69), BMI>> 25 (OR, 1.47; 95% CI, 1.04, 2.06) and high education level (OR, 1.66; 95% CI, 1.06-2.59).

CONCLUSIONS

Reflux oesophagitis and Barrett's oesophagus were not as uncommon as previously thought in a multiracial Asian population and a significant proportion of our patients had severe grades of reflux oesophagitis. NERD, however, still constituted the larger proportion of patients with GORD. Indian race was consistently a significant independent risk factor for reflux oesophagitis, NERD and for GORD overall.

OBJECTIVE

Prolonged air leak (PAL) after pulmonary surgery is a frequent occurrence and is reported to cause increased length of stay (LOS) and hospital costs although the costs directly attributable to PAL have never been published. The present study aims to compare the prevalence of pulmonary complications (atelectasis, pneumonia and pleural empyema) in patients with or without PAL and to quantify economic costs directly incurred by PAL in a series of pulmonary lobectomies.

METHODS

A series of 238 patients scheduled for pulmonary lobectomy (January 2001-December 2003) have been reviewed. PAL was defined as air leakage which prevented hospital discharge for 5 postoperative days or over. Hospital costs (excluding operating room) for pulmonary lobectomies have been obtained and calculated as mean daily costs. Age, body mass index, diagnosis, Charlson co-morbidity index, ppoFEV1 and major post-operative cardio-pulmonary morbidity have been used to construct a Cox-regression model for hospital stay, considering deaths as censored cases. Individual risk function has been used as a new variable and expected LOS calculated for each case. This data has been used to estimate total excess hospital stay and costs incurred by cases with PAL.

RESULTS

Prevalence of PAL was 23 cases (9, 7%). Mean daily hospital cost for lobectomy was 632.49. For the whole series, mean hospital stay was 5 days (10 days for patients with PAL). PAL cases had more postoperative pulmonary morbidity (risk-ratio: 2.78). Variables showing independent influence on stay were: diagnosis of non-malignant disease (P=0.001); FEV1ppo (P=0.032) and cardio-respiratory morbidity (P<0.001). Calculated total excess stay for PAL patients was 62 days. A total expense of 39,437.39 (38,724.96 hospital and 712.43 pharmacy charges) were estimated to result from postoperative air-leak.

CONCLUSIONS

PAL patients are prone to developing major postoperative morbidity. PAL calculated costs are over 13,000 per year. This data is useful for designing technical cost-effective strategies to avoid post-lobectomy PAL.

OBJECTIVE

To determine the incidence of body temperature (BT) alterations in critically ill patients, and their relationship with infection and outcome.

METHODS

Prospective, observational study. SETTING. Thirty-one bed, medico-surgical department of intensive care.

METHODS

Adult patients admitted consecutively to the ICU for at least 24 h, during 6 summer months.

METHODS

None.

RESULTS

Fever (BT>> or =38.3 degrees C) occurred in 139 (28.2%) patients and hypothermia (BT< or =36 degrees C) in 45 (9.1%) patients, at some time during the ICU stay. Fever was present in 52 of 100 (52.0%) infected patients without septic shock, and in 24 of 38 (63.2%) patients with septic shock. Hypothermia occurred in 5 of 100 (5.0%) infected patients without septic shock and in 5 of 38 (13.1%) patients with septic shock. Patients with hypothermia and fever had higher Sequential Organ Failure Assessment (SOFA) scores on admission (6.3+/-3.7 and 6.4+/-3.3 vs 4.6+/-3.2; p<0.01), maximum SOFA scores during ICU stay (7.6+/-5.2 and 8.2+/-4.7 vs 5.4+/-3.8; p<0.01) and mortality rates (33.3 and 35.3% vs 10.3%; p<0.01). The length of stay (<em>LOS</em>) was longer in febrile patients than in hypothermic and normothermic (36 degrees C<BT<38.3 degrees C) patients [median 6 (1-57) vs 5 (2-28) and 3 (1-33) days, p=0.02 and p=0.01, respectively). Among the septic patients hypothermic patients were older than febrile patients (69+/-9 vs 54+/-7 years, p=0.01). Patients with septic shock had a higher mortality if they were hypothermic than if they were febrile (80 vs 50%, p<0.01).

CONCLUSIONS

Both hypothermia and fever are associated with increased morbidity and mortality rates. Patients with hypothermia have a worse prognosis than those with fever.

A 3-part comprehensive synthesis of the early intensive behavioral intervention (EIBI) for young children with autism based on the University of California at Los Angeles Young Autism Project method (Lovaas in Journal of Consulting and Clinical Psychology, 55, 3-9, 1987) is presented. The three components of the synthesis were: (a) descriptive analyses, (b) effect size analyses, and (c) a meta-analysis. The findings suggest EIBI is an effective treatment, on average, for children with autism. The conditions under which this finding applies and the limitations and cautions that must be taken when interpreting the results are discussed within the contextual findings of the moderator analyses conducted in the meta-analysis.

Brain metastasis from breast cancer is an increasingly important clinical problem. Here we assessed the role of CD44(hi)/CD24(lo) cells and pathways that regulate them, in an experimental model of brain metastasis. Notch signaling (mediated by γ-secretase) has been shown to contribute to maintenance of the cancer stem cell (CSC) phenotype. Cells sorted for a reduced stem-like phenotype had a reduced ability to form brain metastases compared with unsorted or CD44(hi)/CD24(lo) cells (P < 0.05; Kruskal-Wallis). To assess the effect of γ-secretase inhibition, cells were cultured with DAPT and the CD44/CD24 phenotypes quantified. 231-BR cells with a CD44(hi)/CD24(lo) phenotype was reduced by about 15% in cells treated with DAPT compared with DMSO-treated or untreated cells (P = 0.001, ANOVA). In vivo, mice treated with DAPT developed significantly fewer micro- and macrometastases compared with vehicle treated or untreated mice (P = 0.011, Kruskal-Wallis). Notch1 knockdown reduced the expression of CD44(hi)/CD24(lo) phenotype by about 20%. In vitro, Notch1 shRNA resulted in a reduction in cellular growth at 24, 48, and 72 hours time points (P = 0.033, P = 0.002, and P = 0.009, ANOVA) and about 60% reduction in Matrigel invasion was observed (P < 0.001, ANOVA). Cells transfected with shNotch1 formed significantly fewer macrometastases and micrometastases compared with scrambled shRNA or untransfected cells (P < 0.001; Kruskal-Wallis). These data suggest that the CSC phenotype contributes to the development of brain metastases from breast cancer, and this may arise in part from increased Notch activity.

BACKGROUND

Emergency departments (EDs) are traditionally designed to provide rapid evaluation and stabilization and are neither staffed nor equipped to provide prolonged care. Longer ED length of stay (LOS) may compromise quality of care and contribute to delays in the emergency evaluation of other patients.

OBJECTIVE

The objective was to determine whether ED LOS increased between 2001 and 2005 and whether trends varied by patient and hospital factors.

METHODS

This was a retrospective analysis of a nationally representative sample of 138,569 adult ED visits from the National Hospital Ambulatory Medical Care Survey (NHAMCS), 2001 to 2005. ED LOS was measured from registration to discharge.

RESULTS

Median ED LOS increased 3.5% per year from 132 minutes in 2001 to 154 minutes in 2005 (p-value for trend < 0.001). There was a larger increase among critically ill patients for whom ED LOS increased 7.0% annually from 185 minutes in 2001 to 254 minutes in 2005 (p-value for trend < 0.01). ED LOS was persistently longer for black/African American, non-Hispanic patients (10.6% longer) and Hispanic patients (13.9% longer) than for non-Hispanic white patients, and these differences did not diminish over time. Among factors potentially associated with increasing ED LOS, a large increase was found (60.1%, p-value for trend < 0.001) in the use of advanced diagnostic imaging (computed tomography [CT], magnetic resonance imaging [MR], and ultrasound [US]) and in the proportion of ED visits at which five or more diagnostic or screening tests were ordered (17.6% increase, p-value for trend = 0.001). The proportion of uninsured patients was stable throughout the study period, and EDs with predominately privately insured patients experienced significant increases in ED LOS (4.0% per year from 2001 to 2005, p-value for trend < 0.01).

CONCLUSIONS

Emergency department LOS in the United States is increasing, especially for critically ill patients for whom time-sensitive interventions are most important. The disparity of longer ED LOS for African Americans and Hispanics is not improving.

While experiments in animals demonstrate neurotoxic effects of particulate matter (PM) and ozone (O3), epidemiologic evidence is sparse regarding the relationship between different constituencies of air pollution mixtures and cognitive function in adults. We examined cross-sectional associations between various ambient air pollutants [O3, PM2.5 and nitrogen dioxide (NO2)] and six measures of cognitive function and global cognition among healthy, cognitively intact individuals (n=1496, mean age 60.5 years) residing in the Los Angeles Basin. Air pollution exposures were assigned to each residential address in 2000-06 using a geographic information system that included monitoring data. A neuropsychological battery was used to assess cognitive function; a principal components analysis defined six domain-specific functions and a measure of global cognitive function was created. Regression models estimated effects of air pollutants on cognitive function, adjusting for age, gender, race, education, income, study and mood. Increasing exposure to PM2.5 was associated with lower verbal learning (β=-0.32 per 10 μg/m(3) PM2.5, 95% CI=-0.63, 0.00; p=0.05). Ambient exposure to NO2 >20 ppb tended to be associated with lower logical memory. Compared to the lowest level of exposure to ambient O3, exposure above 49 ppb was associated with lower executive function. Including carotid artery intima-media thickness, a measure of subclinical atherosclerosis, in models as a possible mediator did not attenuate effect estimates. This study provides support for cross-sectional associations between increasing levels of ambient O3, PM2.5 and NO2 and measures of domain-specific cognitive abilities.

Differentiation of proinflammatory CD4⁺ conventional T cells (T_conv) is critical for productive antitumor responses yet their elicitation remains poorly understood. We comprehensively characterized myeloid cells in tumor draining lymph nodes (tdLN) of mice and identified two subsets of conventional type-2 dendritic cells (cDC2) that traffic from tumor to tdLN and present tumor-derived antigens to CD4⁺ T_conv, but then fail to support antitumor CD4⁺ T_conv differentiation. Regulatory T cell (T_reg) depletion enhanced their capacity to elicit strong CD4⁺ T_conv responses and ensuing antitumor protection. Analogous cDC2 populations were identified in patients, and as in mice, their abundance relative to T_reg predicts protective ICOS⁺ PD-1^lo CD4⁺ T_conv phenotypes and survival. Further, in melanoma patients with low T_reg abundance, intratumoral cDC2 density alone correlates with abundant CD4⁺ T_conv and with responsiveness to anti-PD-1 therapy. Together, this highlights a pathway that restrains cDC2 and whose reversal enhances CD4⁺ T_conv abundance and controls tumor growth.

OBJECTIVE

The primary purpose of this article is to report 12-month prevalence rates and predictors of alcohol abuse and dependence among Mexican Americans, Cuban Americans, Puerto Ricans, and South/Central Americans living in the United States.

METHODS

Using a multistage cluster sample design, a total of 5,224 individuals 18 years of age and older were selected from the household population in five metropolitan areas of the United States: Miami, New York, Philadelphia, Houston, and Los Angeles. The survey weighted response rate was 76%. Personal interviews lasting an average of 1 hour were conducted in respondents' homes either in English or Spanish.

RESULTS

There is considerable heterogeneity in rates of abuse and dependence across these national groups, with Mexican American and Puerto Rican men having higher rates than Cuban American and South/Central American men. The rates of dependence for Mexican American and Puerto Rican men are also higher than those for men in the U.S. general population. Further, although the highest rates of abuse and dependence are among those in their 20s, the rate decline with age is not as strong as in the U.S. population. Thus, Hispanics at older ages (40-49, 50-59) are at considerably more risk of dependence and its health consequences than the U.S. general population. This is particularly true of Puerto Rican and Mexican American men.

CONCLUSIONS

Future analysis must take this heterogeneity into consideration by conducting national group-specific analysis. Prevention efforts must also be guided by these findings, which suggest that Puerto Ricans and Mexican Americans are at higher risk for abuse, dependence, and the associated consequences than the other two groups of U.S. Hispanics.

Although overproduction of proinflammatory 5-lipoxygenase (5-LO)-derived leukotrienes (LTs) has been demonstrated in the lungs of patients with pulmonary fibrosis, their causal involvement in this condition has not been established. Bleomycin-induced pulmonary fibrosis was studied in mice rendered LT deficient by knockout of the 5-LO gene (KO) and in wild-type (WT) control mice. Following administration of bleomycin, lung lavage fluid of WT mice demonstrated an approximately 5-fold increase in levels of cysteinyl-LTs over baseline levels at Day 1, with persistent elevation up to Day 21. As compared with WT mice, 5-LO KO mice demonstrated reduced amounts of histologically evident collagen as well as an approximately 60% reduction in lung hydroxyproline levels postbleomycin. Unlike WT mice, KO mice showed no increases in the numbers of lung inflammatory cells postbleomycin. Furthermore, in situ expression and stimulated production by mixed lung leukocytes of the antifibrotic cytokine interferon-gamma were significantly greater in cells from the 5-LO KO mice. Finally, lavage levels of the antiinflammatory and antifibrotic molecule, prostaglandin E(2), were significantly greater in the KO animals. These results provide strong evidence that LTs may participate in the pathogenesis of pulmonary fibrosis, and they may do so by direct effects as well as indirect effects occurring via their modulation of the synthesis of other inflammatory mediators.

NIDDM is usually characterized by beta-cell failure and decreased insulin sensitivity. It has been reported that a high proportion of African-American NIDDM subjects are insulin sensitive. To examine this issue, we determined insulin sensitivity (S(I)) in 479 NIDDM subjects by minimal model analyses of frequently sampled intravenous glucose tolerance (FSIGT) from the Insulin Resistance Atherosclerosis Study (IRAS), a large multicenter study of insulin sensitivity and cardiovascular risk in African-Americans, Hispanics, and non-Hispanic whites. The African-Americans and non-Hispanic whites were sampled in Los Angeles and Oakland, California. The non-Hispanic whites and Hispanics were sampled in San Antonio, Texas, and San Luis Valley, Colorado. We defined the proportion of insulin-sensitive (S(I)) subjects as>> or =1.61 min-1 x microU-1 x ml-1, which is above the median for nondiabetic subjects of all ethnic groups in the IRAS. Using this definition, the proportion of insulin-sensitive diabetic subjects was very low in all ethnic groups (non-Hispanic whites [14.3%] vs. African-Americans [6.5%], P = 0.039 in Los Angeles and Oakland; non-Hispanic whites [6.8%] vs. Hispanics [4.9%], P = 0.737 in San Luis Valley and San Antonio). These results were also similar in newly diagnosed mildly hyperglycemic diabetic subjects. In addition, these results were not affected by the adjustment for differences in obesity, body fat distribution, and severity of hyperglycemia. Even in nonobese subjects (with BMI <30 kg/m2), the proportion of insulin-sensitive subjects (S(I)>> or =1.61 min-1 x microU-1 x ml-1) was low (3.6-9.7%). The acute insulin response (AIR) was significantly higher in African-Americans than in non-Hispanic whites; there were no ethnic differences in AIR between Hispanics and non-Hispanic whites. There were no significant ethnic differences for non-insulin-mediated glucose disposal (S(G)). We conclude that the number of insulin-sensitive NIDDM subjects is low and similar among non-Hispanic whites, Hispanics, and African-Americans in the U.S.

OBJECTIVE

We tested a theory of syndemic production among men who have sex with men (MSM) using data from a large cohort study.

METHODS

Participants were 1551 men from the Multicenter AIDS Cohort Study enrolled at 4 study sites: Baltimore, Maryland-Washington, DC; Chicago, Illinois; Los Angeles, California; and Pittsburgh, Pennsylvania. Participants who attended semiannual visits from April 1, 2008, to March 31, 2009, completed an additional survey that captured data about events throughout their life course thought to be related to syndemic production.

RESULTS

Using multivariate analysis, we found that the majority of life-course predictor variables (e.g., victimization, internalized homophobia) were significantly associated with both the syndemic condition and the component psychosocial health outcomes (depressive symptoms, stress, stimulant use, sexual compulsivity, intimate partner violence). A nested negative binomial analysis showed that the overall life course significantly explained variability in the syndemic outcomes (χ(2) = 247.94; P < .001; df = 22).

CONCLUSIONS

We identified life-course events and conditions related to syndemic production that may help to inform innovative interventions that will effectively disentangle interconnecting health problems and promote health among MSM.

Frog sartorius muscles tetanized isometrically were released at a constant velocity from lengths lL to lS (delta l = lL -lS; Ls greater than lO). The tension PS redeveloped after the release was lower than the isometric tension PS at LS, and higher than the isometric tension PL at lL. The tension deficit D is defined as the difference PS-PS. The timing of the release during the tetanus did not influence D. D/PO was proportional to delta l/lO. The proportionality constant k was equal to 1.35 +/- 0.19 (n = 8) when the velocity of release was 2.5 mm/s. When the muscles were released the same delta l, D was found to be an exponential decreasing function of the velocity. The tension deficit was also found in experiments performed in the region lS less than lO. The proportionality constant k was smaller, but the influence of the velocity of the release on D was not modified. When the velocity of the release was changed during the release, D changed accordingly, showing that the effects of delta l and V are multiplicative. These facts suggest a working hypothesis based on the concept that the actin filaments which enter the overlap region during a release are strained by the tetanic stress and therefore unable to make normal cross-bridges.