The vitamin D status of a general adult urban population was estimated between November and April in 1569 subjects selected from 20 French cities grouped in nine geographical regions (between latitude 43 degrees and 51 degrees N). Major differences in 25-hydroxyvitamin D (25(OH)D) concentration were found between regions, the lowest values being seen in the North and the greatest in the South, with a significant 'sun' effect (r = 0.72; p = 0.03) and latitude effect (r = -0.79; p = 0.01). In this healthy adult population, 14% of subjects exhibited 25(OH)D values < or = 30 nmol/l (12 ng/ml), which represents the lower limit (< 2 SD) for a normal adult population measured in winter with the same method (RIA Incstar). A significant negative correlation was found between serum intact parathyroid hormone (iPTH) and serum 25(OH)D values (p < 0.01). Serum iPTH held a stable plateau level at 36 pg/ml as long as serum 25(OH)D values were higher than 78 nmol/l (31 ng/ml), but increased when the serum 25(OH)D value fell below this. When the 25(OH)D concentration became equal to or lower than 11.3 nmol/l (4.6 ng/ml), the PTH values reached the upper limit of normal values (55 pg/ml) found in vitamin D replete subjects. These results showed that in French normal adults living in an urban environment with a lack of direct exposure to sunshine, diet failed to provide an adequate amount of vitamin D. It is important to pay attention to this rather high prevalence of vitamin D insufficiency in the general adult population and to discuss the clinical utility of winter supplementation with low doses of vitamin D.

Regulatory T cells (Tregs) limit autoimmunity but also attenuate the magnitude of antipathogen and antitumor immunity. Understanding the mechanism of Treg function and therapeutic manipulation of Tregs in vivo requires identification of Treg-selective receptors. A comparative analysis of gene expression arrays from antigen-specific CD4(+) T cells differentiating to either an effector/memory or a regulatory phenotype revealed Treg-selective expression of LAG-3, a CD4-related molecule that binds MHC class II. Antibodies to LAG-3 inhibit suppression by induced Tregs both in vitro and in vivo. Natural CD4(+)CD25(+) Tregs express LAG-3 upon activation, which is significantly enhanced in the presence of effector cells, whereas CD4(+)CD25(+) Tregs from LAG-3(-/-) mice exhibit reduced regulatory activity. Lastly, ectopic expression of LAG-3 on CD4(+) T cells significantly reduces their proliferative capacity and confers on them suppressor activity toward effector T cells. We propose that LAG-3 marks regulatory T cell populations and contributes to their suppressor activity.

BACKGROUND

The gut hormone fragment peptide YY3-36 (PYY) reduces appetite and food intake when infused into subjects of normal weight. In common with the adipocyte hormone leptin, PYY reduces food intake by modulating appetite circuits in the hypothalamus. However, in obesity there is a marked resistance to the action of leptin, which greatly limits its therapeutic effectiveness. We investigated whether obese subjects were also resistant to the anorectic effects of PYY.

METHODS

We compared the effects of PYY infusion on appetite and food intake in 12 obese and 12 lean subjects in a double-blind, placebo-controlled, crossover study. The plasma levels of PYY, ghrelin, leptin, and insulin were also determined.

RESULTS

Caloric intake during a buffet lunch offered two hours after the infusion of PYY was decreased by 30 percent in the obese subjects (P<0.001) and 31 percent in the lean subjects (P<0.001). PYY infusion also caused a significant decrease in the cumulative 24-hour caloric intake in both obese and lean subjects. PYY infusion reduced plasma levels of the appetite-stimulatory hormone ghrelin. Endogenous fasting and postprandial levels of PYY were significantly lower in obese subjects (the mean [+/-SE] fasting PYY levels were 10.2+/-0.7 pmol per liter in the obese group and 16.9+/-0.8 pmol per liter in the lean group, P<0.001). Furthermore, the fasting PYY levels correlated negatively with the body-mass index (r = -0.84, P<0.001).

CONCLUSIONS

We found that obese subjects were not resistant to the anorectic effects of PYY. Endogenous PYY levels were low in the obese subjects, suggesting that PYY deficiency may contribute to the pathogenesis of obesity.

N-acetylcysteine has been widely used as an antioxidant in vivo and in vitro. Its reaction with four oxidant species has therefore been examined. N-acetylcysteine is a powerful scavenger of hypochlorous acid (H--OCl); low concentrations are able to protect alpha 1-antiproteinase against inactivation by HOCl. N-acetylcysteine also reacts with hydroxyl radical with a rate constant of 1.36 X 10(10) M-1s-1, as determined by pulse radiolysis. It also reacts slowly with H2O2, but no reaction of N-acetylcysteine with superoxide (O2-) could be detected within the limits of our assay procedures.

Substrate stiffness is emerging as an important physical factor in the response of many cell types. In agreement with findings on other anchorage-dependent cell lineages, aortic smooth muscle cells are found to spread and organize their cytoskeleton and focal adhesions much more so on "rigid" glass or "stiff" gels than on "soft" gels. Whereas these cells generally show maximal spreading on intermediate collagen densities, the limited spreading on soft gels is surprisingly insensitive to adhesive ligand density. Bell-shaped cell spreading curves encompassing all substrates are modeled by simple functions that couple ligand density to substrate stiffness. Although smooth muscle cells spread minimally on soft gels regardless of collagen, GFP-actin gives a slight overexpression of total actin that can override the soft gel response and drive spreading; GFP and GFP-paxillin do not have the same effect. The GFP-actin cells invariably show an organized filamentous cytoskeleton and clearly indicate that the cytoskeleton is at least one structural node in a signaling network that can override spreading limits typically dictated by soft gels. Based on such results, we hypothesize a central structural role for the cytoskeleton in driving the membrane outward during spreading whereas adhesion reinforces the spreading.

Targeted mutation of TGFbeta1 in mice demonstrated that TGFbeta1 is one of the key negative regulators of immune homeostasis, as its absence leads to activation of a self-targeted immune response. Nevertheless, because of the highly pleiotropic properties of TGFbeta and the presence of TGFbeta receptors on most cell types, its biologic role in the regulation of immune homeostasis is not yet understood. To limit the consequences of TGFbeta effects to a single cell type, we developed a transgenic approach to abrogate the TGFbeta response in key immune cells. Specifically, we expressed a dominant-negative TGFbeta receptor type II under a T cell-specific promoter and created a mouse model where signaling by TGFbeta is blocked specifically in T cells. Using this transgenic model, we show that T cell homeostasis requires TGFbeta signaling in T cells.

Key cellular decisions, such as proliferation or growth arrest, typically occur at spatially defined locations within tissues. Loss of this spatial control is a hallmark of many diseases, including cancer. Yet, how these patterns are established is incompletely understood. Here, we report that physical and architectural features of a multicellular sheet inform cells about their proliferative capacity through mechanical regulation of YAP and TAZ, known mediators of Hippo signaling and organ growth. YAP/TAZ activity is confined to cells exposed to mechanical stresses, such as stretching, location at edges/curvatures contouring an epithelial sheet, or stiffness of the surrounding extracellular matrix. We identify the F-actin-capping/severing proteins Cofilin, CapZ, and Gelsolin as essential gatekeepers that limit YAP/TAZ activity in cells experiencing low mechanical stresses, including contact inhibition of proliferation. We propose that mechanical forces are overarching regulators of YAP/TAZ in multicellular contexts, setting responsiveness to Hippo, WNT, and GPCR signaling.

Selection of the translational initiation site in most eukaryotic mRNAs appears to occur via a scanning mechanism which predicts that proximity to the 5' end plays a dominant role in identifying the start codon. This "position effect" is seen in cases where a mutation creates an AUG codon upstream from the normal start site and translation shifts to the upstream site. The position effect is evident also in cases where a silent internal AUG codon is activated upon being relocated closer to the 5' end. Two mechanisms for escaping the first-AUG rule--reinitiation and context-dependent leaky scanning--enable downstream AUG codons to be accessed in some mRNAs. Although these mechanisms are not new, many new examples of their use have emerged. Via these escape pathways, the scanning mechanism operates even in extreme cases, such as a plant virus mRNA in which translation initiates from three start sites over a distance of 900 nt. This depends on careful structural arrangements, however, which are rarely present in cellular mRNAs. Understanding the rules for initiation of translation enables understanding of human diseases in which the expression of a critical gene is reduced by mutations that add upstream AUG codons or change the context around the AUG(START) codon. The opposite problem occurs in the case of hereditary thrombocythemia: translational efficiency is increased by mutations that remove or restructure a small upstream open reading frame in thrombopoietin mRNA, and the resulting overproduction of the cytokine causes the disease. This and other examples support the idea that 5' leader sequences are sometimes structured deliberately in a way that constrains scanning in order to prevent harmful overproduction of potent regulatory proteins. The accumulated evidence reveals how the scanning mechanism dictates the pattern of transcription--forcing production of monocistronic mRNAs--and the pattern of translation of eukaryotic cellular and viral genes.

Resistance to chemotherapy limits the effectiveness of anti-cancer drug treatment. Tumours may be intrinsically drug-resistant or develop resistance to chemotherapy during treatment. Acquired resistance is a particular problem, as tumours not only become resistant to the drugs originally used to treat them, but may also become cross-resistant to other drugs with different mechanisms of action. Resistance to chemotherapy is believed to cause treatment failure in over 90% of patients with metastatic cancer, and resistant micrometastic tumour cells may also reduce the effectiveness of chemotherapy in the adjuvant setting. Clearly, if drug resistance could be overcome, the impact on survival would be highly significant. This review focuses on molecular mechanisms of drug resistance that operate to reduce drug sensitivity in cancer cells. Drug resistance can occur at many levels, including increased drug efflux, drug inactivation, alterations in drug target, processing of drug-induced damage, and evasion of apoptosis. Advances in DNA microarray and proteomic technology, and the ongoing development of new targeted therapies have opened up new opportunities to combat drug resistance. We are now able to characterize the signalling pathways involved in regulating tumour cell response to chemotherapy more completely than ever before. This will facilitate the future development of rational combined chemotherapy regimens, in which the newer targeted therapies are used in combination with cytotoxic drugs to enhance chemotherapy activity. The ability to predict response to chemotherapy and to modulate this response with targeted therapies will permit selection of the best treatment for individual patients.

The myocardium of the failing heart undergoes a number of structural alterations, most notably hypertrophy of cardiac myocytes and an increase in extracellular matrix proteins, often seen as primary fibrosis. Connective tissue growth factor (CTGF) is a key molecule in the process of fibrosis and therefore seems an attractive therapeutic target. Regulation of CTGF expression at the promoter level has been studied extensively, but it is unknown how CTGF transcripts are regulated at the posttranscriptional level. Here we provide several lines of evidence to show that CTGF is importantly regulated by 2 major cardiac microRNAs (miRNAs), miR-133 and miR-30. First, the expression of both miRNAs was inversely related to the amount of CTGF in 2 rodent models of heart disease and in human pathological left ventricular hypertrophy. Second, in cultured cardiomyocytes and fibroblasts, knockdown of these miRNAs increased CTGF levels. Third, overexpression of miR-133 or miR-30c decreased CTGF levels, which was accompanied by decreased production of collagens. Fourth, we show that CTGF is a direct target of these miRNAs, because they directly interact with the 3' untranslated region of CTGF. Taken together, our results indicate that miR-133 and miR-30 importantly limit the production of CTGF. We also provide evidence that the decrease of these 2 miRNAs in pathological left ventricular hypertrophy allows CTGF levels to increase, which contributes to collagen synthesis. In conclusion, our results show that both miR-133 and miR-30 directly downregulate CTGF, a key profibrotic protein, and thereby establish an important role for these miRNAs in the control of structural changes in the extracellular matrix of the myocardium.

Interleukin 27 (IL-27) was first characterized as a proinflammatory cytokine with T helper type 1-inducing activity. However, subsequent work has demonstrated that mice deficient in IL-27 receptor (IL-27R alpha) show exacerbated inflammatory responses to a variety of challenges, suggesting that IL-27 has important immunoregulatory functions in vivo. Here we demonstrate that IL-27R alpha-deficient mice were hypersusceptible to experimental autoimmune encephalomyelitis and generated more IL-17-producing T helper cells. IL-27 acted directly on effector T cells to suppress the development of IL-17-producing T helper cells mediated by IL-6 and transforming growth factor-beta. This suppressive activity was dependent on the transcription factor STAT1 and was independent of interferon-gamma. Finally, IL-27 suppressed IL-6-mediated T cell proliferation. These data provide a mechanistic explanation for the IL-27-mediated immune suppression noted in several in vivo models of inflammation.

Upon the aberrant activation of oncogenes, normal cells can enter the cellular senescence program, a state of stable cell-cycle arrest, which represents an important barrier against tumour development in vivo. Senescent cells communicate with their environment by secreting various cytokines and growth factors, and it was reported that this 'secretory phenotype' can have pro- as well as anti-tumorigenic effects. Here we show that oncogene-induced senescence occurs in otherwise normal murine hepatocytes in vivo. Pre-malignant senescent hepatocytes secrete chemo- and cytokines and are subject to immune-mediated clearance (designated as 'senescence surveillance'), which depends on an intact CD4(+) T-cell-mediated adaptive immune response. Impaired immune surveillance of pre-malignant senescent hepatocytes results in the development of murine hepatocellular carcinomas (HCCs), thus showing that senescence surveillance is important for tumour suppression in vivo. In accordance with these observations, ras-specific Th1 lymphocytes could be detected in mice, in which oncogene-induced senescence had been triggered by hepatic expression of Nras(G12V). We also found that CD4(+) T cells require monocytes/macrophages to execute the clearance of senescent hepatocytes. Our study indicates that senescence surveillance represents an important extrinsic component of the senescence anti-tumour barrier, and illustrates how the cellular senescence program is involved in tumour immune surveillance by mounting specific immune responses against antigens expressed in pre-malignant senescent cells.

Cells with loss of BRCA2 function are defective in homologous recombination (HR) and are highly sensitive to inhibitors of poly(ADP-ribose) polymerase (PARP), which provides the basis for a new therapeutic approach. Here we show that resistance to PARP inhibition can be acquired by deletion of a mutation in BRCA2. We derived PARP-inhibitor-resistant (PIR) clones from the human CAPAN1 pancreatic cancer cell line, which carries the protein-truncating c.6174delT frameshift mutation. PIR clones could form DNA-damage-induced RAD51 nuclear foci and were able to limit genotoxin-induced genomic instability, both hallmarks of a competent HR pathway. New BRCA2 isoforms were expressed in the resistant lines as a result of intragenic deletion of the c.6174delT mutation and restoration of the open reading frame (ORF). Reconstitution of BRCA2-deficient cells with these revertant BRCA2 alleles rescued PARP inhibitor sensitivity and HR deficiency. Most of the deletions in BRCA2 were associated with small tracts of homology, and possibly arose from error-prone repair caused by BRCA2 deficiency. Similar ORF-restoring mutations were present in carboplatin-resistant ovarian tumours from c.6174delT mutation carriers. These observations have implications for understanding drug resistance in BRCA mutation carriers as well as in defining functionally important domains within BRCA2.

BACKGROUND

Experimental evidence suggests that cyclosporine, which inhibits the opening of mitochondrial permeability-transition pores, attenuates lethal myocardial injury that occurs at the time of reperfusion. In this pilot trial, we sought to determine whether the administration of cyclosporine at the time of percutaneous coronary intervention (PCI) would limit the size of the infarct during acute myocardial infarction.

METHODS

We randomly assigned 58 patients who presented with acute ST-elevation myocardial infarction to receive either an intravenous bolus of 2.5 mg of cyclosporine per kilogram of body weight (cyclosporine group) or normal saline (control group) immediately before undergoing PCI. Infarct size was assessed in all patients by measuring the release of creatine kinase and troponin I and in a subgroup of 27 patients by performing magnetic resonance imaging (MRI) on day 5 after infarction.

RESULTS

The cyclosporine and control groups were similar with respect to ischemia time, the size of the area at risk, and the ejection fraction before PCI. The release of creatine kinase was significantly reduced in the cyclosporine group as compared with the control group (P=0.04). The release of troponin I was not significantly reduced (P=0.15). On day 5, the absolute mass of the area of hyperenhancement (i.e., infarcted tissue) on MRI was significantly reduced in the cyclosporine group as compared with the control group, with a median of 37 g (interquartile range, 21 to 51) versus 46 g (interquartile range, 20 to 65; P=0.04). No adverse effects of cyclosporine administration were detected.

CONCLUSIONS

In our small, pilot trial, administration of cyclosporine at the time of reperfusion was associated with a smaller infarct by some measures than that seen with placebo. These data are preliminary and require confirmation in a larger clinical trial.

Nuclear compartmentalization seems to have an important role in regulating metazoan genes. Although studies on immunoglobulin and other loci have shown a correlation between positioning at the nuclear lamina and gene repression, the functional consequences of this compartmentalization remain untested. We devised an approach for inducible tethering of genes to the inner nuclear membrane (INM), and tested the consequences of such repositioning on gene activity in mouse fibroblasts. Here, using three-dimensional DNA-immunoFISH, we demonstrate repositioning of chromosomal regions to the nuclear lamina that is dependent on breakdown and reformation of the nuclear envelope during mitosis. Moreover, tethering leads to the accumulation of lamin and INM proteins, but not to association with pericentromeric heterochromatin or nuclear pore complexes. Recruitment of genes to the INM can result in their transcriptional repression. Finally, we use targeted adenine methylation (DamID) to show that, as is the case for our model system, inactive immunoglobulin loci at the nuclear periphery are contacted by INM and lamina proteins. We propose that these molecular interactions may be used to compartmentalize and to limit the accessibility of immunoglobulin loci to transcription and recombination factors.

Gastrointestinal (GI) tract damage by chemotherapy or radiation limits their efficacy in cancer treatment. Radiation has been postulated to target epithelial stem cells within the crypts of Lieberkühn to initiate the lethal GI syndrome. Here, we show in mouse models that microvascular endothelial apoptosis is the primary lesion leading to stem cell dysfunction. Radiation-induced crypt damage, organ failure, and death from the GI syndrome were prevented when endothelial apoptosis was inhibited pharmacologically by intravenous basic fibroblast growth factor (bFGF) or genetically by deletion of the acid sphingomyelinase gene. Endothelial, but not crypt, cells express FGF receptor transcripts, suggesting that the endothelial lesion occurs before crypt stem cell damage in the evolution of the GI syndrome. This study provides a basis for new approaches to prevent radiation damage to the bowel.

The sensitivity of the requirement of Methanobacterium ruminantium strain M1 to a new coenzyme, 2-mercaptoethanesulfonic acid (HS-CoM) was examined by use of new techniques that were developed for rapid and efficient handling of large numbers of cultures of methanogenic bacteria. The system uses sealed tubes that contain a gas mixture of 80% hydrogen and 20% carbon dioxide under a pressure of 2 to 3 atm. This modification of the Hungate technique reduces variability among replicate cultures and simplifies the dispensing, sterilization, and storage of liquid media as well as the transfer and maintenance of methanogenic bacteria. Results indicate a limit of sensitivity of the assay at 5 nM HS-CoM, with half-maximal growth at 25 nM HS-CoM. Coenzyme activity could be replaced by 2,2'-dithiodiethanesulfonic acid at a half-molar equivalent of the HS-CoM concentration, or by 2-(methylthio)ethanesulfonic acid on an equimolar basis. These data reveal a very sensitive and precise requirement for HS-CoM in the nutrition of this fastidious anaerobe.

DOT1 was originally identified as a gene affecting telomeric silencing in S. cerevisiae. We now find that Dot1p methylates histone H3 on lysine 79, which maps to the top and bottom of the nucleosome core. Methylation occurs only when histone H3 is assembled in chromatin. In vivo, Dot1p is solely responsible for this methylation and methylates approximately 90% of histone H3. In dot1delta cells, silencing is compromised and silencing proteins become redistributed at the expense of normally silenced loci. We suggest that methylation of histone H3 lysine 79 limits silencing to discrete loci by preventing the binding of Sir proteins elsewhere along the genome. Because Dot1p and histone H3 are conserved, similar mechanisms are likely at work in other eukaryotes.

BACKGROUND

Apixaban, an oral factor Xa inhibitor administered in fixed doses, may simplify the treatment of venous thromboembolism.

METHODS

In this randomized, double-blind study, we compared apixaban (at a dose of 10 mg twice daily for 7 days, followed by 5 mg twice daily for 6 months) with conventional therapy (subcutaneous enoxaparin, followed by warfarin) in 5395 patients with acute venous thromboembolism. The primary efficacy outcome was recurrent symptomatic venous thromboembolism or death related to venous thromboembolism. The principal safety outcomes were major bleeding alone and major bleeding plus clinically relevant nonmajor bleeding.

RESULTS

The primary efficacy outcome occurred in 59 of 2609 patients (2.3%) in the apixaban group, as compared with 71 of 2635 (2.7%) in the conventional-therapy group (relative risk, 0.84; 95% confidence interval [CI], 0.60 to 1.18; difference in risk [apixaban minus conventional therapy], -0.4 percentage points; 95% CI, -1.3 to 0.4). Apixaban was noninferior to conventional therapy (P<0.001) for predefined upper limits of the 95% confidence intervals for both relative risk (<1.80) and difference in risk (<3.5 percentage points). Major bleeding occurred in 0.6% of patients who received apixaban and in 1.8% of those who received conventional therapy (relative risk, 0.31; 95% CI, 0.17 to 0.55; P<0.001 for superiority). The composite outcome of major bleeding and clinically relevant nonmajor bleeding occurred in 4.3% of the patients in the apixaban group, as compared with 9.7% of those in the conventional-therapy group (relative risk, 0.44; 95% CI, 0.36 to 0.55; P<0.001). Rates of other adverse events were similar in the two groups.

CONCLUSIONS

A fixed-dose regimen of apixaban alone was noninferior to conventional therapy for the treatment of acute venous thromboembolism and was associated with significantly less bleeding (Funded by Pfizer and Bristol-Myers Squibb; ClinicalTrials.gov number, NCT00643201).

In the 1960s, total hip replacement revolutionised management of elderly patients crippled with arthritis, with very good long-term results. Today, young patients present for hip-replacement surgery hoping to restore their quality of life, which typically includes physically demanding activities. Advances in bioengineering technology have driven development of hip prostheses. Both cemented and uncemented hips can provide durable fixation. Better materials and design have allowed use of large-bore bearings, which provide an increased range of motion with enhanced stability and very low wear. Minimally invasive surgery limits soft-tissue damage and facilitates accelerated discharge and rehabilitation. Short-term objectives must not compromise long-term performance. Computer-assisted surgery will contribute to reproducible and accurate placement of implants. Universal economic constraints in healthcare services dictate that further developments in total hip replacement will be governed by their cost-effectiveness.

BACKGROUND

Transmission intensity affects almost all aspects of malaria epidemiology and the impact of malaria on human populations. Maps of transmission intensity are necessary to identify populations at different levels of risk and to evaluate objectively options for disease control. To remain relevant operationally, such maps must be updated frequently. Following the first global effort to map Plasmodium falciparum malaria endemicity in 2007, this paper describes the generation of a new world map for the year 2010. This analysis is extended to provide the first global estimates of two other metrics of transmission intensity for P. falciparum that underpin contemporary questions in malaria control: the entomological inoculation rate (PfEIR) and the basic reproductive number (PfR).

METHODS

Annual parasite incidence data for 13,449 administrative units in 43 endemic countries were sourced to define the spatial limits of P. falciparum transmission in 2010 and 22,212 P. falciparum parasite rate (PfPR) surveys were used in a model-based geostatistical (MBG) prediction to create a continuous contemporary surface of malaria endemicity within these limits. A suite of transmission models were developed that link PfPR to PfEIR and PfR and these were fitted to field data. These models were combined with the PfPR map to create new global predictions of PfEIR and PfR. All output maps included measured uncertainty.

RESULTS

An estimated 1.13 and 1.44 billion people worldwide were at risk of unstable and stable P. falciparum malaria, respectively. The majority of the endemic world was predicted with a median PfEIR of less than one and a median PfRc of less than two. Values of either metric exceeding 10 were almost exclusive to Africa. The uncertainty described in both PfEIR and PfR was substantial in regions of intense transmission.

CONCLUSIONS

The year 2010 has a particular significance as an evaluation milestone for malaria global health policy. The maps presented here contribute to a rational basis for control and elimination decisions and can serve as a baseline assessment as the global health community looks ahead to the next series of milestones targeted at 2015.

The recent discovery that hydrogen sulfide (H(2)S) is an endogenously produced gaseous second messenger capable of modulating many physiological processes, much like nitric oxide, prompted us to investigate the potential of H(2)S as a cardioprotective agent. In the current study, we demonstrate that the delivery of H(2)S at the time of reperfusion limits infarct size and preserves left ventricular (LV) function in an in vivo model of myocardial ischemia-reperfusion (MI-R). This observed cytoprotection is associated with an inhibition of myocardial inflammation and a preservation of both mitochondrial structure and function after I-R injury. Additionally, we show that modulation of endogenously produced H(2)S by cardiac-specific overexpression of cystathionine gamma-lyase (alpha-MHC-CGL-Tg mouse) significantly limits the extent of injury. These findings demonstrate that H(2)S may be of value in cytoprotection during the evolution of myocardial infarction and that either administration of H(2)S or the modulation of endogenous production may be of clinical benefit in ischemic disorders.

BACKGROUND

The Alcohol Use Disorders Identification Test Consumption (AUDIT-C) questions have been previously validated as a 3-item screen for alcohol misuse and implemented nationwide in Veterans Affairs (VA) outpatient clinics. However, the AUDIT-C's validity and optimal screening threshold(s) in other clinical populations are unknown.

METHODS

This cross-sectional validation study compared screening questionnaires with standardized interviews in 392 male and 927 female adult outpatients at an academic family practice clinic from 1993 to 1994. The AUDIT-C, full AUDIT, self-reported risky drinking, AUDIT question #3, and an augmented CAGE questionnaire were compared with an interview primary reference standard of alcohol misuse, defined as a Diagnostic and Statistical Manual, 4th ed. alcohol use disorder and/or drinking above recommended limits in the past year.

RESULTS

Based on interviews with 92% of eligible patients, 128 (33%) men and 177 (19%) women met the criteria for alcohol misuse. Areas under the receiver operating characteristic curves (AUROCs) for the AUDIT-C were 0.94 (0.91, 0.96) and 0.90 (0.87, 0.93) in men and women, respectively (p=0.04). Based on AUROC curves, the AUDIT-C performed as well as the full AUDIT and significantly better than self-reported risky drinking, AUDIT question #3, or the augmented CAGE questionnaire (p-values <0.001). The AUDIT-C screening thresholds that simultaneously maximized sensitivity and specificity were>> or =4 in men (sensitivity 0.86, specificity 0.89) and>> or =3 in women (sensitivity 0.73, specificity 0.91).

CONCLUSIONS

The AUDIT-C was an effective screening test for alcohol misuse in this primary care sample. Optimal screening thresholds for alcohol misuse among men >> or =4) and women >> or =3) were the same as in previously published VA studies.

In healthy individuals, acute changes in cholesterol intake produce modest changes in plasma cholesterol levels. A striking exception occurs in sitosterolemia, an autosomal recessive disorder characterized by increased intestinal absorption and decreased biliary excretion of dietary sterols, hypercholesterolemia, and premature coronary atherosclerosis. We identified seven different mutations in two adjacent, oppositely oriented genes that encode new members of the adenosine triphosphate (ATP)-binding cassette (ABC) transporter family (six mutations in ABCG8 and one in ABCG5) in nine patients with sitosterolemia. The two genes are expressed at highest levels in liver and intestine and, in mice, cholesterol feeding up-regulates expressions of both genes. These data suggest that ABCG5 and ABCG8 normally cooperate to limit intestinal absorption and to promote biliary excretion of sterols, and that mutated forms of these transporters predispose to sterol accumulation and atherosclerosis.