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Increased leucocyte apoptosis in transfused β-thalassaemia patients.

This exploratory study assessed apoptosis in peripheral blood leucocytes (PBL) from β-thalassaemia patients receiving chronic transfusions and chelation therapy (deferasirox or deferoxamine) at baseline, 1, 6, and 12 months. At baseline, thalassaemic PBLs presented 50% greater levels of Bax (BAX), 75% higher caspase-3/7, 48% higher caspase-8 and 88% higher caspase-9 activities and 428% more nucleosomal DNA fragmentation than control subjects. Only neutrophils correlated significantly with apoptotic markers. Previously, we showed that over the treatment year, hepatic iron declined; we now show …

Инъекции нейтрофильного апоптоза с помощью вируса энцефалита.

Вирус энцефалита, передаваемый через тик, заражает нейтрофилов и вызывает их апоптоз, судя по умеренному увеличению активности сучканата дегидрогеназы и тенденции к анаэробному производству энергии у нейтрофилов, инфицированных этим вирусом (за счет увеличения активности лактата дегидрогеназы).

Совпадение в аннотации оригинала
Tick-borne encephalitis virus infects neutrophils and induces their apoptosis, judging from moderate increase of succinate dehydrogenase activity and a trend to anaerobic energy production in neutrophils infected with the virus (shown by an increase of lactate dehydrogenase activity).

Mitochondrial-dependent apoptosis in Huntington's disease human cybrids.

We investigated the involvement of mitochondrial-dependent apoptosis in Huntington's disease (HD) vs. control (CTR) cybrids, obtained from the fusion of human platelets with mitochondrial DNA-depleted NT2 cells, and further exposed to 3-nitropropionic acid (3-NP) or staurosporine (STS). Untreated HD cybrids did not exhibit significant modifications in the activity of mitochondrial respiratory chain complexes I-IV or in mtDNA sequence variations suggestive of a primary role in mitochondrial susceptibility in the subpopulation of HD carriers studied. However, a slight decrease in mitochondrial m…

Bacteremia causes hippocampal apoptosis in experimental pneumococcal meningitis.

BACKGROUND: Bacteremia and systemic complications both play important roles in brain pathophysiological alterations and the outcome of pneum … . uninfected controls (n = 6). RESULTS: Pneumococcal meningitis resulted in a significantly higher apoptosis score 0.22 (0.18-0.35) compared to uninfected controls (0.02 (0.00-0.02), Mann Whitney test, P = 0.0003). Also, meningitis with an attenuation of bacteremia by antibody treatment resulted in significantly reduced apoptosis (0.08 (0.02-0.20), P = 0.0 …

Electrical stimulation prevents apoptosis in denervated skeletal muscle.

The purpose of this study was to investigate the hypothesis that electrical stimulation regulates the levels of gene expression related to apoptosis in denervated muscle and prevents muscle atrophy after denervation.Nineteen rats were used in this study. To denervate soleus muscle, sciatic nerve was resected under aseptic condition. Electrical stimulation with 4 mA rectangular pulses of 0.5 ms duration at 2 Hz lasting for 1 hour was delivered to lower limb including the soleus muscle using two surface electrodes. After the stimulation periods of 4 weeks, the levels of gene expression related t…

Otosclerosis: disturbed balance between cell survival and apoptosis.

HYPOTHESIS: Otosclerosis is an inflammatory bone remodeling disorder of the human otic capsule, which might be characterized by a disturbed balance between cell survival and apoptosis due to an increased expression of inflammatory cytokines, mainly tumor necrosis factor-[alpha] (TNF-[alpha]). BACKGROUND: Histologic features of otosclerosis have been well described; however, different histopathologic and clinical stages have not been attributed precisely to the molecular biology of the pathologically increased metabolism of bone-forming and bone-resorbing cells. METHODS: Forty ankylotic stape…

Phenylephrine protects autotransplanted rabbit submandibular gland from apoptosis.

Submandibular gland (SMG) autotransplantation is an effective treatment for severe keratoconjunctivitis sicca. Our previous studies have shown that phenylephrine attenuates structural injury and promotes cell proliferation in autotransplanted rabbit SMG. However, the mechanism by which phenylephrine reduces the injury has not been fully evaluated. In this study, we investigate the ability of phenylephrine to inhibit apoptosis in autotransplanted rabbit SMG. We observed that apoptosis occurred in the early phase of SMG transplantation and that phenylephrine treatment protected transplanted SMG …

[Multiple medication resistance of apoptosis-resistant tumoral cells].

A4 clone cells, received by CD95-mediated selection from the parental line of Jurkat T-lymphoblast human leukosis, lost their ability of apoptosis as a result of programmed cell death mechanism breakdown. The complex of their acquired phenotypic properties meets tumor progression criteria: oxidative stress resistance, active immune suppression, and low requirement for growth factors. The loss of A4 cell ability of apoptosis is accompanied by acquisition of the phenotype of multiple medication resistance to a wide spectrum of antineoplastic chemotherapeutic drugs and cytotoxins.

Methylmercury induces pancreatic beta-cell apoptosis and dysfunction.

Mercury is a well-known toxic metal, which induces oxidative stress. Pancreatic beta-cells are vulnerable to oxidative stress. The pathophys … e in mercury levels with a dose-dependent manner. Moreover, MeHg displayed several features of cell apoptosis including an increase of the sub-G1 population and annexin-V binding. Treatment of HIT-T15 cells with MeHg resulted in disruption of the mitochondrial membrane potential and release of cytochrome c from the mitochondria to the cytosol and activation …

H2O2 intensifies CN(-)-induced apoptosis in pea leaves.

H2O2 intensifies CN(-)-induced apoptosis in stoma guard cells and to lesser degree in basic epidermal cells in peels of the lower epidermis isolated from pea leaves. The maximum effect of H2O2 on guard cells was observed at 10(-4) M. By switching on non-cyclic electron transfer in chloroplasts menadione and methyl viologen intensified H2O2 generation in the light, but prevented the CN--induced apoptosis in guard cells. The light stimulation of CN- effect on guard cell apoptosis cannot be caused by disturbance of the ribulose-1,5-bisphosphate carboxylase function and associated OH* generation i…

Motexafin gadolinium induces mitochondrially-mediated caspase-dependent apoptosis.

Motexafin gadolinium (MGd, Xcytrin) is a tumor-localizing redox mediator that catalyzes the oxidation of intracellular reducing molecules in … prior to caspase-8, cleavage of PARP and annexin V binding. There was minimal effect on MGd-induced apoptosis by the caspase inhibitor z-VAD-fmk, even though caspase-3 activity (as measured by DEVD-cleavage) was completely inhibited. However, MGd-induced apoptosis was reduced to baseline levels by the more potent caspase inhibitor Q-VD-OPh, demonstrating th …

Neuronal gelsolin prevents apoptosis by enhancing actin depolymerization.

Gelsolin (gsn), an actin-severing protein, protects neurons from excitotoxic cell death via inactivation of membranous Ca(2+) channels. Its role during apoptotic cell death, however, has remained unclear. Using several models of neuronal cell death, we demonstrate that endogenous gelsolin has anti-apoptotic properties that correlate to its dynamic actions on the cytoskeleton. We show that neurons lacking gelsolin (gsn(-/-)) have enhanced apoptosis following exposure to staurosporine, thapsigargin, or the cholinergic toxin ethylcholine aziridinium (AF64A). AF64A-induced loss of mitochondrial me…

Anthrax lethal toxin induces human endothelial cell apoptosis.

Because of its ease of dispersal and high lethality, Bacillus anthracis is one of the most feared biowarfare agents. A better understanding … reduces the viability of cultured human endothelial cells and induces caspase-dependent endothelial apoptosis. In addition, this toxicity affects both microvascular and large vessel endothelial cells as well as endothelial cells that have differentiated into tubules within a type I collagen extracellular matrix. Finally, lethal toxin induces cleavage of mit …

Caspase-3 mediates hippocampal apoptosis in pneumococcal meningitis.

Bacterial meningitis causes neuronal apoptosis in the hippocampal dentate gyrus, which is associated with learning and memory impairments after cured disease. The execution of the apoptotic program involves pathways that converge on activation of caspase-3, which is required for morphological changes associated with apoptosis. Here, the time course and the role of caspase-3 in neuronal apoptosis was assessed in an infant rat model of pneumococcal meningitis. During clinically asymptotic meningitis (0-12 h after infection), only minor apoptotic damage to the dentate gyrus was observed, while th…

Maspin sensitizes breast carcinoma cells to induced apoptosis.

Maspin, a novel serine protease inhibitor (serpin), suppresses the growth and metastasis of breast tumor in vivo. However, the underlying molecular mechanism is unclear. In the current study, we report the first evidence that endogenous maspin expression in mammary carcinoma cells MDA-MB-435 enhanced staurosporine (STS)-induced apoptosis as judged by the increased fragmentation of DNA, increased proteolytic inactivation of poly-[ADP-ribose]-polymerase (PARP), as well as the increased activation of caspase-8 and caspase-3. In parallel, recombinant maspin did not directly regulate the proteolyti…

Bacterial toxin RelE induces apoptosis in human cells.

The bacterial protein RelE severely restricts prokaryotic cell growth, probably by acting as a global inhibitor of translation. It is ubiquitous in prokaryotes as part of the RelE-RelB toxin-antitoxin system, and may be activated by nutritional stress. When the relE gene from Escherichia coli was expressed inducibly in a human osteosarcoma cell line, it was shown to retard growth and to lead to cell death by apoptosis. RelE is therefore unusual among bacterial toxins in possessing broad activity against both prokaryotes and eukaryotes, perhaps by acting on evolutionarily conserved components o…

Cell darwinism, apoptosis, free radicals and haematological malignancies.

Haematopoiesis can be interpreted as an ecosystem composed of billions of cells interacting according to Darwinian rules. Mutation, by promoting cell diversity, ensures versatility in coping with internal and external challenges. Most mutated cells are eliminated through apoptosis. However, if mutation generates relative resistance to apoptosis it may result in growth advantage for the mutated cells. The probability of monoclonality and malignancy is significantly increased if the normal multiclonal environment is damaged by a pathologic proapoptotic process that spares the apoptosis resistant…

Survival motor neuron protein modulates neuron-specific apoptosis.

Spinal muscular atrophy (SMA) is attributed to mutations in the SMN1 gene, leading to loss of spinal cord motor neurons. The neurotropic Sindbis virus vector system was used to investigate a role for the survival motor neuron (SMN) protein in regulating neuronal apoptosis. Here we show that SMN protects primary neurons and differentiated neuron-like stem cells, but not cultured cell lines from virus-induced apoptotic death. SMN also protects neurons in vivo and increases survival of virus-infected mice. SMN mutants (SMNDelta7 and SMN-Y272C) found in patients with SMA not only lack antiapoptoti…

Aspirin induces apoptosis through mitochondrial cytochrome c release.

Aspirin and other non-steroidal anti-inflammatory drugs induce apoptosis in many cell types. Although the involvement of caspases has been demonstrated, the mechanism leading to caspase activation remains unknown. We have studied the role of the mitochondrial pathway in aspirin-induced apoptosis. The apoptotic effect of aspirin was analyzed in different cell lines (Jurkat, MOLT-4, Raji and HL-60) showing induction of mitochondrial cytochrome c release and caspases 9, 3 and 8 processing. Furthermore, early aspirin-induced cytochrome c release was not affected by the caspase inhibitor Z-VAD x fm…

Oxidative stress inhibits apoptosis in human lymphoma cells.

Apoptosis and necrosis are two forms of cell death that are induced under different conditions and that differ in morphological and biochemical features. In this report, we show that, in the presence of oxidative stress, human B lymphoma cells are unable to undergo apoptosis and die instead by a form of necrosis. This was established using the chemotherapy drug VP-16 or the calcium ionophore A23187 to induce apoptosis in Burkitt's lymphoma cell lines and by measuring classical markers of apoptotic death, including cell morphology, annexin V binding, DNA ladder formation, and caspase activation…