Fas and Fas ligand in embryos and adult mice: ligand expression in several immune-privileged tissues and coexpression in adult tissues characterized by apoptotic cell turnover.

The cell surface receptor Fas (FasR, Apo-1, CD95) and its ligand (FasL) are mediators of apoptosis that have been shown to be implicated in the peripheral deletion of autoimmune cells, activation-induced T cell death, and one of the two major cytolytic pathways mediated by CD8+ cytolytic T cells. To gain further understanding of the Fas system., we have analyzed Fas and FasL expression during mouse development and in adult tissues. In developing mouse embryos, from 16.5 d onwards, Fas mRNA is detectable in distinct cell types of the developing sinus, thymus, lung, and liver, whereas FasL expression is restricted to submaxillary gland epithelial cells and the developing nervous system. Significant Fas and FasL expression were observed in several nonlymphoid cell types during embryogenesis, and generally Fas and FasL expression were not localized to characteristic sites of programmed cell death. In the adult mouse, RNase protection analysis revealed very wide expression of both Fas and FasL. Several tissues, including the thymus, lung, spleen, small intestine, large intestine, seminal vesicle, prostate, and uterus, clearly coexpress the two genes. Most tissues constitutively coexpressing Fas and FasL in the adult mouse are characterized by apoptotic cell turnover, and many of those expressing FasL are known to be immune privileged. It may be, therefore, that the Fas system is implicated in both the regulation of physiological cell turnover and the protection of particular tissues against potential lymphocyte-mediated damage.

Pneumocystis jirovecii genotype associated with increased death rate of HIV-infected patients with pneumonia.

Pneumocystis jirovecii dihydropteroate synthase (DHPS) mutations have been associated with failure of sulfa prophylaxis; their effect on the outcome of patients with P. jirovecii pneumonia (PCP) remains controversial. P. jirovecii DHPS polymorphisms and genotypes were identified in 112 cases of PCP in 110 HIV-infected patients by using PCR single-strand conformation polymorphism. Of the 110 patients observed, 21 died; 18 of those deaths were attributed to PCP. Thirty-three percent of the PCP cases involved a P. jirovecii strain that had 1 or both DHPS mutations. The presence or absence of DHPS mutations had no effect on the PCP mortality rate within 1 month, whereas P.jirovecii type 7 and mechanical ventilation at PCP diagnosis were associated with an increased risk of death caused by PCP. Mechanical ventilation at PCP diagnosis was also associated with an increased risk of sulfa treatment failure at 5 days.

Remorins form a novel family of coiled coil-forming oligomeric and filamentous proteins associated with apical, vascular and embryonic tissues in plants.

Remorins form a superfamily of plant-specific plasma membrane/lipid-raft-associated proteins of unknown structure and function. Using specific antibodies, we localized tomato remorin 1 to apical tissues, leaf primordia and vascular traces. The deduced remorin protein sequence contains a predicted coiled coil-domain, suggesting its participation in protein-protein interactions. Circular dichroism revealed that recombinant potato remorin contains an alpha-helical region that forms a functional coiled-coil domain. Electron microscopy of purified preparations of four different recombinant remorins, one from potato, two divergent isologs from tomato, and one from Arabidopsis thaliana , demonstrated that the proteins form highly similar filamentous structures. The diameters of the negatively-stained filaments ranged from 4.6-7.4 nm for potato remorin 1, 4.3-6.2 nm for tomato remorin 1, 5.7-7.5 nm for tomato remorin 2, and 5.7-8.0 nm for Arabidopsis Dbp. Highly polymerized remorin 1 was detected in glutaraldehyde-crosslinked tomato plasma membrane preparations and a population of the protein was immunolocalized in tomato root tips to structures associated with discrete regions of the plasma membrane.

Lack of the alanine-serine-cysteine transporter 1 causes tremors, seizures, and early postnatal death in mice.

The Na(+)-independent alanine-serine-cysteine transporter 1 (Asc-1) is exclusively expressed in neuronal structures throughout the central nervous system (CNS). Asc-1 transports small neutral amino acids with high affinity especially for D-serine and glycine (K(i): 8-12 microM), two endogenous glutamate co-agonists that activate N-methyl-D-aspartate (NMDA) receptors through interacting with the strychnine-insensitive glycine binding-site. By regulating D-serine (and possibly glycine) levels in the synaptic cleft, Asc-1 may play an important role in controlling neuronal excitability. We generated asc-1 gene knockout (asc-1(-/-)) mice to test this hypothesis. Behavioral phenotyping combined with electroencephalogram (EEG) recordings revealed that asc-1(-/-) mice developed tremors, ataxia, and seizures that resulted in early postnatal death. Both tremors and seizures were reduced by the NMDA receptor antagonist MK-801. Extracellular recordings from asc-1(-/-) brain slices indicated that the spontaneous seizure activity did not originate in the hippocampus, although, in this region, a relative increase in evoked synaptic responses was observed under nominal Mg(2+)-free conditions. Taken together with the known neurochemistry and neuronal distribution of the Asc-1 transporter, these results indicate that the mechanism underlying the behavioral hyperexcitability in mutant mice is likely due to overactivation of NMDA receptors, presumably resulting from elevated extracellular D-serine. Our study provides the first evidence to support the notion that Asc-1 transporter plays a critical role in regulating neuronal excitability, and indicate that the transporter is vital for normal CNS function and essential to postnatal survival of mice.

Interruptions of cART limits CD4 T-cell recovery and increases the risk for opportunistic complications and death.

BACKGROUND: A major goal of antiretroviral therapy (ART) for HIV-1-infected persons is the recovery of CD4 T lymphocytes, resulting in thorough protection against opportunistic complications. Interruptions of ART are still frequent. The long-term effect on CD4 T-cell recovery and clinical events remains unknown. METHODS: Immunological and clinical endpoints were evaluated in 2491 participants of the Swiss HIV Cohort Study initiating ART during a mean follow-up of 7.1 years. Data were analysed in persons with treatment interruptions (n = 1271; group A), continuous ART, but intermittent HIV-1 RNA at least 1000 copies/ml (n = 469; group B) and continuous ART and HIV-1 RNA constantly less than 1000 copies/ml (n = 751; group C). Risk factors for low CD4 T-cell counts and clinical events were analysed using Cox proportional hazards models. RESULTS: In groups A-C, CD4 T lymphocytes increased to a median of 427, 525 and 645 cells/μl at 8 years. In group A, 63.0 and 37.2% reached above 350 and 500 CD4 T cells/μl, whereas in group B 76.3 and 55.8% and in group C 87.3 and 68.0% reached these thresholds (P < 0.001). CD4 T-cell recovery directly depended on the cumulative duration of treatment interruptions. In addition, participants of group A had more Centers for Disease Control and Prevention B/C events, resulting in an increased risk of death. Major risk factors for not reaching CD4 T cells above 500 cells/μl included lower baseline CD4 T-cell count, higher age and hepatitis C virus co-infection. CONCLUSION: In persons receiving continuous ART larger CD4 T-cell recovery and a reduced risk for opportunistic complications and death was observed. CD4 T-cell recovery was smaller in persons with treatment interruptions more than 6 months.

Death following acute poisoning by moclobemide

A fatality due to ingestion of a reversible inhibitor of monoamine-oxidase A (MAO-A) is reported. Moclobemide is generally considered as a safe drug far less toxic than tricyclic anti-depressants. However, severe intoxications may result from interactions with other drugs and food such as selective serotonin reuptake inhibitors (SSRIs), anti-Parkinsonians of the MAOI-type (e.g. selegiline) or tyramine from ripe cheese or other sources. In the present case, high levels of moclobemide were measured in peripheral blood exceeding toxic values reported so far in the scientific literature. The body fluid concentrations of moclobemide were of 498 mg/l in peripheral whole blood, 96.3 mg/l in urine while an amount of approximately 33 g could be recovered from gastric contents. The other xenobiotics were considered of little toxicological relevance. The victim (male, 48-year-old) had a past history of depression and committed one suicide attempt 2 years before death. Autopsy revealed no evidence of significant natural disease or injury. It was concluded that the manner of death was suicide and that the unique cause of death was massive ingestion of moclobemide.

Cardiovascular Pathology. 004. Pathomorphological and CT-angiographical characteristics of coronary atherosclerotic plaques in cases of sudden cardiac death

Objective. The goal of this study was to present the pathological and radiological patterns of "vulnerable" atherosclerotic plaques in cases of sudden cardiac death. Method. This retrospective study was performed on forensic cases for which the cause of death was attributed to coronary artery disease. A complete autopsy was performed in all cases, along with either post-mortem CT-angiography, toxicological analyses and/or biochemistry. Results. 89 cases were selected (mean age 55±11.6 years; 75 men and 14 women). In 96.6% of cases a CT-angiography was performed. Acute coronary lesions were found in 60 cases (mean age 53±11.1 years), which included plaque erosion in 26 cases (mean age 47±8.3 years) and ruptures or intraplaque hemorrhage in 33 cases (mean age 58±10.4 years). Erosions were most frequently found in the left ascending artery (61.5 %), while only 36% of ruptures were observed in this artery. Chronic coronary pathology was described in 30 cases (mean age 58±10.4 years). CT-angiographies performed prior to the autopsy enabled an initial evaluation of coronary artery perfusion. Conclusion. In the face of decreasing clinical autopsy rates, postmortem studies on forensic autopsies, including modern radiological examinations, allow for a more thorough understanding of the clinical picture of disease which can result in sudden cardiac death.

Estimation du degré de couverture d'un registre pour les cancers notifiés au décès [Evaluation of the comprehensiveness of a cancer register from death certificates].

The comparison of cancer prevalence with cancer mortality can lead under some hypotheses to an estimate of registration rate. A method is proposed, where the cases with cancer as a cause of death are divided into 3 categories: (1) cases already known by the registry (2) unknown cases having occured before the registry creation date (3) unknown cases occuring during the registry operates. The estimate is then the number of cases in the first category divided by the total of those in categories 1 and 3 (these only are to be registered). An application is performed on the data of the Canton de Vaud. Survival rates of the Norvegian Cancer Registry are used for computing the number of unknown cases to be included in second and third category, respectively. The discussion focusses on the possible determinants of the obtained comprehensiveness rates for various cancer sites.

Transgenic reexpression of GLUT1 or GLUT2 in pancreatic beta cells rescues GLUT2-null mice from early death and restores normal glucose-stimulated insulin secretion.

GLUT2-null mice are hyperglycemic, hypoinsulinemic, hyperglucagonemic, and glycosuric and die within the first 3 weeks of life. Their endocrine pancreas shows a loss of first phase glucose-stimulated insulin secretion (GSIS) and inverse alpha to beta cell ratio. Here we show that reexpression by transgenesis of either GLUT1 or GLUT2 in the pancreatic beta cells of these mice allowed mouse survival and breeding. The rescued mice had normal-fed glycemia but fasted hypoglycemia, glycosuria, and an elevated glucagon to insulin ratio. Glucose tolerance was, however, normal. In vivo, insulin secretion assessed following hyperglycemic clamps was normal. In vitro, islet perifusion studies revealed that first phase of insulin secretion was restored as well by GLUT1 or GLUT2, and this was accompanied by normalization of the glucose utilization rate. The ratio of pancreatic insulin to glucagon and volume densities of alpha to beta cells were, however, not corrected. These data demonstrate that 1) reexpression of GLUT1 or GLUT2 in beta cells is sufficient to rescue GLUT2-null mice from lethality, 2) GLUT1 as well as GLUT2 can restore normal GSIS, 3) restoration of GSIS does not correct the abnormal composition of the endocrine pancreas. Thus, normal GSIS does not depend on transporter affinity but on the rate of uptake at stimulatory glucose concentrations.

High expression of the HMG box factor sox-13 in arterial walls during embryonic development.

Members of the Sox gene family of transcription factors are defined by the presence of an 80 amino acid homology domain, the High Mobility Group (HMG) box. Here we report the cloning and initial analysis of murine Sox-13 . The 984 amino acids Sox-13 protein contains a single HMG box, a leucine zipper motif and a glutamine-rich stretch. These characteristics are shared with another member of the Sox gene family, Sox-6. High level embryonic expression of Sox-13 occurs uniquely in the arterial walls of 13.5 days post coitum (dpc) mice and later. Low level expression was observed in the inner ear of 13.5 dpc mice and in a limited number of cells in the thymus of 16.5 dpc mice, from which Sox-13 was originally cloned. At 18.5 dpc, Sox-13 is expressed in the tracheal epithelium below the vocal cord and in the hair follicles. The Sox-13 protein binds to the consensus HMG box motif, AACAAAG, but does not transactivate transcription through a concatamer of this motif. Sox-13, like other members of the Sox family likely plays an important role in development.

Molecular autopsy in sudden cardiac death and its implication for families: discussion of the practical, legal and ethical aspects of the multidisciplinary collaboration.

Sudden cardiac death (SCD) is a major cause of premature death in young adults and children in developed countries. Standard forensic autopsy procedures are often unsuccessful in determining the cause of SCD. Post-mortem genetic testing, also called molecular autopsy, has revealed that a non-negligible number of these deaths are a result of inherited cardiac diseases, including arrhythmic disorders such as congenital long QT syndrome and Brugada syndrome. Due to the heritability of these diseases, the potential implications for living relatives must be taken into consideration. Advanced diagnostic analyses, genetic counselling, and interdisciplinary collaboration should be integral parts of clinical and forensic practice. In this article we present a multidisciplinary collaboration established in Lausanne, with the goal of properly informing families of these pathologies and their implications for surviving family members. In Switzerland, as in many other countries, legal guidelines for genetic testing do not address the use of molecular tools for post-mortem genetic analyses in forensic practice. In this article we present the standard practice guidelines established by our multidisciplinary team.

Chemotherapy in patients with advanced pancreatic cancer: too close to death?

PURPOSE: We evaluated the attitude in using chemotherapy near the end of life in advanced pancreatic adenocarcinoma (PAC). Clinical and laboratory parameters recorded at last chemotherapy administration were analyzed, in order to identify risk factors for imminent death. METHODS: Retrospective analysis of patients who underwent at least one line of palliative chemotherapy was made. Data concerning chemotherapy (regimens, lines, and date of last administration) were collected. Clinical and laboratory factors recorded at last chemotherapy administration were: performance status, presence of ascites, hemoglobin, white blood cell (WBC), platelets, total bilirubin, albumin, LDH, C-reactive protein (C-rp), and Ca 19.9. RESULTS: We analyzed 231 patients: males/females, 53/47 %; metastatic/locally advanced disease, 80/20 %; and median age, 66 years (range 32-85). All patients died due to disease progression. Median overall survival was 6.1 months (95 % CI 5.1-7.2). At the last chemotherapy delivery, performance status was 0-1 in 37 % and 2 in 63 %. Fifty-nine percent of patients received one chemotherapy line, while 32, 8, and 1 % had second-, third-, and fourth line, respectively. The interval between last chemotherapy administration and death was <4 weeks in 24 %, ≥4-12 in 47 %, and >12 in 29 %. Median survival from last chemotherapy to death was 7.5 weeks (95 % CI 6.7-8.4). In a univariate analysis, ascites, elevated WBC, bilirubin, LDH, C-rp and Ca 19.9, and reduced albumin were found to predict shorter survival; however, none of them remained significant in a multivariate analysis. CONCLUSIONS: A significant proportion of patients with advanced PAC received chemotherapy within the last month of life. The clinical and laboratory parameters recorded at last chemotherapy delivery did not predict shorter survival.