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51.
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We studied p38 phosphorylation and its intracellular localization during p53 and Puma (a p53 upregulated modulator of apoptosis) apoptotic signaling pathway in bone marrow granulocytes in mice irradiated in vivo and the role of the radioprotector amifostine in ameliorating these responses. Sixty-four C57BL mice were randomly assigned in two non-irradiated (Ami−/rad− and Ami+/rad−) and two irradiated (Ami−/rad+ and Ami+/rad+) groups. Animals received 400 mg/kg of amifostine i.p. 30 min prior to a single whole body radiation dose of 7 Gy. The experiments were performed using immunohistochemistry for caspase-3, cleaved caspase-3, p53, p-p53 (Ser 15), Puma, p38 and p-p38 (Thr 180/Tyr 182) protein expression. In addition transmission electron microscopy was used for ultrastructural characterization of apoptosis. Data showed that: (i) amifostine significantly reduced the number of apoptotic cells, (ii) p-p53 and Puma proteins were strongly immunostained in granulocytes after irradiation (Ami−/rad+), (iii) amifostine decreased the immunostaining of the proteins (Ami+/rad+), (iv) p38 was immunolocalized in physiological conditions in the nucleus and cytoplasm of granulocytes and neither radiation nor amifostine changed the protein immunostaining or its subcellular distribution, but influenced its activation, (v) radiation-induced p38 phosphorylation and its cytoplasmic accumulation during apoptosis signaling in granulocytes after whole body high radiation dose and amifostine markedly reduced these effects.  相似文献   
53.
Pellagra is a potentially fatal, nutritional disease with cutaneous, gastrointestinal, and neuropsychiatric manifestations. Because of the diversity of pellagra's signs and symptoms, diagnosis is difficult without an appropriate index of suspicion. A case of pellagra in a 14-year-old girl with anorexia nervosa is presented. Signs and symptoms of pellagra were resolved after niacin therapy and dietary treatment.  相似文献   
54.

Objective

Aicardi‐Goutières syndrome (AGS) is an early‐onset encephalopathy resembling congenital viral infection that is characterized by basal ganglia calcifications, loss of white matter, cerebrospinal fluid (CSF) lymphocytosis, and elevated interferon‐α levels in the CSF. Studies have shown that AGS is an autosomal‐recessive disease linked to mutations in 5 genes, encoding the 3′‐repair DNA exonuclease 1 (TREX1), the 3 subunits of ribonuclease H2 (RNASEH2A–C), and sterile alpha motif domain and HD domain–containing protein 1 (SAMHD1). In this study we further characterized the phenotypic spectrum of this disease.

Methods

Clinical and laboratory data were obtained from 26 patients fulfilling the clinical diagnostic criteria for AGS. Genomic DNA was screened for mutations in all 5 AGS genes by direct sequencing, and sera were analyzed for autoantibodies.

Results

In 20 patients with AGS, 20 mutations, 12 of which were novel, were identified in all 5 AGS genes. Clinical and laboratory investigations revealed a high prevalence of features (some not previously described in patients with AGS) that are commonly seen in patients with systemic lupus erythematosus (SLE), such as thrombocytopenia, leukocytopenia, antinuclear antibodies, erythematous lesions, oral ulcers, and arthritis, which were observed in 12 (60%) of 20 patients with AGS. Moreover, the coexistence of AGS and SLE, was for the first time, demonstrated in 2 patients with molecularly proven AGS.

Conclusion

These findings expand the phenotypic spectrum of lupus erythematosus in AGS and provide further insight into its disease mechanisms by showing that activation of the innate immune system as a result of inherited defects in nucleic acid metabolism could lead to systemic autoimmunity.
  相似文献   
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The development of glycine immunoreactivity in the brain of the sea lamprey was studied by use of immunofluorescence techniques at embryonic to larval stages. Glycine distribution was also compared with that of γ‐aminobutyric acid (GABA) by use of double immunofluorescence. The first glycine‐immunoreactive (ir) cells appeared in the caudal rhombencephalon of late embryos, diencephalon of early prolarvae, and mesencephalon of late prolarvae, in which glycine‐ir cells were observed in several prosencephalic regions (preoptic nucleus, hypothalamus, ventral thalamus, dorsal thalamus, pretectum, and nucleus of the medial longitudinal fascicle), mesencephalon (M5), isthmus, and rhombencephalon. In larvae, glycine‐ir populations were observed in the olfactory bulbs, preoptic nucleus and thalamus (prosencephalon), M5 and oculomotor nucleus (mesencephalon), dorsal isthmic gray, isthmic reticular formation, and various alar and basal plate rhombencephalic populations. No glycine‐ir cells were observed in the larval optic tectum or torus semicircularis, which contain glycine‐ir populations in adults. A wide distribution of glycine‐ir fibers was observed, which suggests involvement of glycine in the function of most lamprey brain regions. Colocalization of GABA and glycine in prolarvae was found mainly in cell groups of the diencephalon, in the ventral isthmic group, and in trigeminal populations. In larvae, colocalization of GABA and glycine was principally observed in the M5 nucleus, the reticular formation, and the dorsal column nucleus. The present results reveal for the first time the complex developmental pattern of the glycinergic system in lamprey, including early glycine‐ir populations, populations transiently expressing glycine, and late‐appearing populations, in relation to maturation changes that occur during metamorphosis. J. Comp. Neurol. 512:747–767, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   
57.
We developed an approach to adapt the ASTM C1055-03 Standard to assess the potential for contact burn injury from portable consumer electronic devices. The approach involves measuring the maximum temperature profile during the fault and devising a way to reproduce these temperatures in an exemplar device in a controlled manner for thermesthesiometer measurements. By comparing the results of the thermesthesiometer measurements to the contact burn injury threshold data published in ASTM C1055-03 and various guidelines for unintentional contact times, we were able to predict whether a potential hazard exists and verify result with "finger tests." We applied this method on a number of occasions to assess the likelihood of a contact burn injury resulting from a fault arising inside portable consumer electronic devices.  相似文献   
58.
In this study, double immunofluorescence methods were used to investigate possible colocalization of the neurotransmitters dopamine [DA] and GABA in rostral spinal cord neurones in the upstream migrating adult sea lamprey (Petromyzon marinus). Double immunofluorescence revealed that all the DA-immunoreactive (ir) cerebrospinal fluid-contacting (CSF-c) cells, approximately 30% of the medioventral DA-ir cells, and most of the DA-ir cells located in the grey lateral to the central canal were also GABA-ir. The results also revealed some DA-ir cells located dorsally to the central canal, which increases the number of dopaminergic cell types known in lamprey. Double-labelled fibres were mainly distributed in the ventral column, and double-labelled boutons contacted some dorsal GABA-ir CSF-c cells, as well as some non-CSF-c GABA-ir cells and ventromedial dendrites of motoneurones. The findings reveal colocalization of dopamine and GABA in some cells and fibres, which suggests co-release of these substances in some synaptic terminals. Although dopaminergic/GABAergic CSF-c cells have been reported in some other vertebrates, the other double-labelled spinal populations appear exclusive to lampreys.  相似文献   
59.
The Geastrum saccatum a mushroom, native to Brazil, is produced under natural conditions in the unexplored reserve of Mata da Estrela-RN. This species has curative properties for eye infections and diseases such as asthma. The tissues of this mushroom contain carbohydrates, proteins, lipids, moisture and ashes in amounts of 42.3%, 37.05%, 9.01, 1.4% and 10.2%, respectively. An extract from this mushroom was characterized by chemical analyses and (13)C and (1)H NMR spectroscopy. It contains high amount of glucose and traces of galactose. The signal appearing at 103.5 ppm was assigned to C1 of beta-glucose. The signals observed between 20 and 40 ppm suggest the presence of a glucan-protein compound. This glucan inhibited the lipid peroxidation at the dose of 0.27 mg/mL (59.1%) and it can protect cells against oxidative stress by scavenging of the hydroxyl (77%) and superoxide (88.4%) radicals at 0.27 mg/mL. The glucan (30 mg/kg) reduces the polymorphonuclear cell migration (57.6%). The ear edema induced by croton oil was inhibited by glucan (60.4% at 10 mg/kg) and by its association with diclofenac (5 mg/kg) (89.2%) or L-NAME (60 mg/kg) (86.23%). Histological analyses of the ear edema induced by croton oil in the presence of glucan (10, 30 or 50 mg/kg) showed a reduced degree of the polymorphonuclear cell migration. We concluded that the glucan has antioxidant, and antiinflammatory properties as well as its antiinflammatory effect are mediated by inhibition of both nitric oxide synthase (NOS) and cyclooxygenase (COX).  相似文献   
60.
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