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1.
Cyclic neutropenia is a rare immunodeficiency syndrome, characterized by regular periodic oscillations in the circulating neutrophil count from normal to neutropenic levels through 3 weeks period, and lasting for 3-6 days. In order to determine the clinical features of cyclic neutropenia, this study was performed. Seven patients with cyclic neutropenia (3 males and 4 females), who experienced neutropenic periods every 3 weeks (5 with severe and 2 with moderate neutropenia), were investigated in this study. They had been referred to Iranian Primary Immunodeficiency Registry during 23 years (1980-2003). The range of patients' ages was from 7 to 13 years (median 11 years). The median age at the onset of the disease was 12 months (1 month- 2 years) and the median age of diagnosis was 2 (1.5-5) years, with a median diagnosis delay of 1 year (2 months- 5 years). Neutropenia was associated with leukopenia (3 patients), anemia (3 patients), and thrombocytopenia (1 patient). Patients were asymptomatic in healthy phase, but during the episode of neutropenia suffered from aphthous ulcers, abscesses and overwhelming infections. The most commonly occurred manifestations were: otitis media (6 cases), oral ulcers (5 cases), abscesses (4 cases), pneumonia (3 cases), diarrhea (3 cases), oral candidiasis (3 cases), cutaneous infections (2 cases), and periodontitis (2 cases). One of these patients subsequently died because of recurrent infections. Unusual, persistent or severe infections should be the initiating factors to search for an immune deficiency syndrome such as cyclic neutropenia, because a delay in diagnosis may result in chronic infection, irretrievable end-organ damage or even death of the patient.  相似文献   
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Amniotic membrane (AM), the innermost layer of the fetal membrane, is considered as a suitable candidate for cancer therapy. In order to develop the AM as a new cancer therapeutic approach, it is essential to understand the molecular mechanism of the AM anti-cancer properties. Previous studies demonstrated that anti-proliferative effects of the AM on tumor cells were associated with induction of cell cycle arrest. Moreover, it has been shown that unknown substances in the AM induce apoptosis in cancer cells and inhibit angiogenesis in tumors. In contrast to the effects of the AM, heat shock proteins (HSPs), in particular HSP90, play a crucial role in development of tumorgenesis. HSP90 inhibits apoptosis in cancer cells and enhances angiogenesis and cell cycle progression. Based on the opposite effects of the amniotic membrane ingredients and HSP90, we hypothesized here that possible mechanism of the AM anti-cancer effects is through inhibition of HSP90.  相似文献   
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Two important pathophysiological mechanisms involved during cerebral ischemia are oxidative stress and inflammation. In pathological conditions such as brain ischemia the ability of free radicals production is greater than that of elimination by endogenous antioxidative systems, so brain is highly injured due to oxidation and neuroinflammation. Fibrates as peroxisome proliferator-activated receptor (PPAR)-α ligands, are reported to have antioxidant and anti-inflammatory actions. In this study, gemfibrozil, a fibrate is investigated for its therapeutic potential against global cerebral ischemia–reperfusion (I/R) injury of male and female rats. This study particularly has focused on inflammatory and antioxidant signaling pathways, such as nuclear factor erythroid-related factor (Nrf)-2, as well as the activity of some endogenous antioxidant agents. It was found that pretreatment of animals with gemfibrozil prior to I/R resulted in a sexually dimorphic outcome. Within females it proved to be protective, modulating inflammatory factors and inducing antioxidant defense system including superoxide dismutase (SOD), catalase, as well as glutathione level. However, Nrf-2 signaling pathway was not affected. It also decreased malondialdehyde level as an index of lipid peroxidation. In contrast, gemfibrozil pretreatment was toxic to males, enhancing the expression of inflammatory factors such as tumor necrosis factor-α, nuclear factor-κB, and cyclooxygenase-2, and decreasing Nrf-2 expression and SOD activity, leading to hippocampal neurodegeneration. Considering that gemfibrozil is a commonly used anti-hyperlipidemic agent in clinic, undoubtedly more investigations are crucial to exactly unravel its sex-dependent neuroprotective/neurodegenerative potential.  相似文献   
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Impaired memory performance in offspring is one of the long-lasting neurobehavioral consequences of prenatal opiate exposure. Here, we studied the effects of prenatal morphine exposure on inhibitory avoidance memory performance in male and female offspring and also investigated whether these deficits are reversible during the postnatal development. Pregnant Wistar rats received morphine sulfate through drinking water, from the first day of gestation up to the day 13, M1–13, or to the time of delivery, M1–21. Four- and ten-week-old (adolescent and adult, respectively) male and female offspring were subjected to behavioral assays and then analysis of proteins involved in apoptosis or in synaptic plasticity. Results revealed that adolescent and adult female rats failed in passive avoidance retention task in both M1–13 and M1–21 groups. Adolescent and adult male offspring were similar to control animals in M1–13 group. However M1–21 impaired retention task in prepubertal male offspring, and this memory loss was repaired in postpubertal stage. Consistently, Bax/Bcl-2 ratio and cleaved caspase-3 were significantly increased in both M1–13 and M1–21 adolescent and adult female rats, but only in M1–21 adolescent male rats. Furthermore, prenatal morphine exposure reduced the expression of brain-derived neurotrophic factor precursor protein in adolescent and adult female offspring and also decreased p-ca(2+)/calmodulin-dependent kinase II/ca(2+)/calmodulin-dependent kinase II ratio in adolescent male and female rats. Altogether, the results show that prenatal morphine exposure, depending on the time or duration of exposure, has distinct effects on male and female rats, and postnatal development may reverse these deficits more likely in males.  相似文献   
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It has been shown that nifedipine, as a calcium channel blocker, can attenuate the development of tolerance to the antinociceptive effect of morphine; however, the role of HPA axis on this action has not been elucidated. We examined the effect of nifedipine on morphine analgesic tolerance in intact and adrenalectomized (ADX) rats and on HPA activity induced by morphine. Adult male rats were rendered tolerant to morphine by daily injection of morphine (15 mg/kg i.p.) for 8 days. To determine the effect of nifedipine on the development of morphine tolerance, nifedipine (1, 2 and 5 mg/kg i.p.) was injected concomitant with morphine. The tail-flick test was used to assess the nociceptive threshold, before and 30 min after morphine administration in days 1, 3, 5 and 8. Our results showed that despite the demonstration of tolerance in both ADX and sham operated rats, nifedipine in ADX rats prevented morphine tolerance development at a lower dose (2 mg/kg) than in sham operated rats, however corticosterone replacement prevented nifedipine effect in ADX rats. Acute administration of morphine produced significant increase in plasma corticosterone level, and with repeated injection, a tolerance to this neurosecretory effect was developed. Nifedipine (5 mg/kg) attenuated the acute effect of morphine, but could not block its neurosecretory tolerance.  相似文献   
7.
Most drugs of abuse increase dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) release in the shell of the nucleus accumbens. The effects of ascorbate, which is known to modulate dopamine neurotransmission, on the extracellular level of DOPAC in the nucleus accumbens of naive rats and of rats treated acutely with morphine were studied by using in vivo microdialysis and high performance liquid chromatography with electrochemical detection (HPLC-ECD). Acute morphine (20 mg/kg ip) treatment increased the level of DOPAC in the nucleus accumbens to approximately 170% of basal level. Acute treatment with ascorbate (500 mg/kg ip) alone did not alter nucleus accumbens' DOPAC level, but pretreatment with ascorbate (500 mg/kg ip) 30 min before morphine administration attenuated the effects of acute morphine on the level of DOPAC. These results suggest that ascorbate modulates the mesolimbic dopaminergic pathway.  相似文献   
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Renal oncocytoma is a rare benign tumor. Bilateral and multifocal renal oncocytoma has rarely been described in childhood. We report a 12-year-old girl who presented with massive left renomegaly and who was found to have bilateral cystic kidneys. A left nephrectomy was undertaken because of the renal enlargement, the radiological evidence of extensive disease, and to make a diagnosis. A diagnosis of multifocal oncocytoma was made after detailed histological examination.  相似文献   
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