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31.
We report a novel mutation in FcgammaRIIIA (the transmembrane-form CD16) on natural killer (NK) cells in a patient with polyneuropathy. She had no history of recurrent infections. Her NK cells expressed no detectable CD16; however, her NK cytotoxic activity was normal, suggesting that CD16 expression and cytotoxic activity are independent of one another. Molecular analysis revealed a deletion of a single adenine base in exon 4 of CD16 at nucleotide 550. This deletion generates a STOP codon in an extra-cellular domain of the FcgammaRIIIA gene, thereby truncating the CD16 molecule. The patient's NK cells were not recognized by the anti-CD16 monoclonal antibodies 3G8 and Leu11c. Whether the development of her polyneuropathy is associated with this novel mutation is unclear.  相似文献   
32.
The present study was designed to investigate the role of Ca(2+)-activated Cl(-) channels in the spinal opioid receptor-mediated antinociception using the mouse tail-flick assay. The antinociception induced by intrathecal (i.t.) administration of a selective delta-opioid receptor agonist [D-Ala(2)]deltorphin II (10 microgram, i.t.) was significantly attenuated by i.t.-pretreatment with selective Ca(2+)-activated Cl(-) channel blockers, IAA-94, flufenamic acid and niflumic acid. By contrast, IAA-94 had no effect on the antinociception induced by i.t.-treated with either the selective mu-opioid receptor agonist [D-Ala(2),N-MePhe(4), Gly-ol(5)]enkephalin or the kappa-opioid receptor agonist U-50,488H. The present results provide evidence for the first time that the Ca(2+)-activated Cl(-) channel is, at least in part, implicated in the delta-, but not the mu- and kappa-opioid receptor-mediated antinociception in the mouse spinal cord.  相似文献   
33.
A 35 kD protein was isolated and purified from conditioned media of Bcl-2 cDNA-transfected PC12 cells and its cDNA cloned. A database analysis showed that the 35 kD protein is a rat homologue of the human FLRG protein. The biochemical as well as morphological properties of the rat FLRG protein in PC12 cells were examined and its distribution in rat tissues determined. The levels of FLRG mRNA expressed were low during the fetal period, compared with those of follistatin mRNA. The distribution of FLRG and follistatin mRNAs differed from each other after birth; the expression levels of FLRG mRNA were abundant in the adrenal gland and testis, whereas those of follistatin mRNA and activin A were markedly high in the ovary. The presence of FLRG mRNA and/or protein was confirmed in spermatocytes at various differentiating stages andin endocrine cells of both the adrenal cortex and medulla. When overexpressed in PC12 cells, the FLRG protein was found to be stored in secretory granules of the cells and largely secreted by a regulated pathway, while activin A enhancedthe constitutive secretion of the FLRG protein from wild-typpe PC12 cells, indicating that the FLRG protein possesses dualproperties in secretory pathways. The different distribution between FLRG and follistatin mRNA suggests that, like follistatin in the ovary, the FLRG protein may be involved in the maintenance of spermatogenesis in the testis and the growth and function of adrenal tissue cells, probably by regulating the functions of its binding partners such as the TGF-beta ( superfamily members.  相似文献   
34.
Despite advances in medical technology, careful specimen identification is still a fundamental principle of laboratory testing. If pathological samples are mixed up, especially in the case of extremely small biopsy samples, large amounts of time and energy may be wasted in correctly identifying the specimens. Recently, two liver biopsy specimens were mixed up in this department, and a new pathological technology was used to resolve the issue. Liver biopsy was performed on two patients with hepatitis C virus (HCV) infection. During sample transfer or tissue processing, the biopsy specimens were mixed up. Because the ABO blood group of the two patients was identical (type AB), the specimens were subsequently identified by analysing the HCV genotypes. RNA extracted from the paraffin wax embedded liver specimens was examined by a polymerase chain reaction based HCV genotype assay. This enabled the correct identification of the specimens, and each patient received the appropriate treatment on the basis of the accurate diagnosis.  相似文献   
35.
The effect of electro-acupuncture stimulation (EAS) on duodenal motility was examined in anesthetized, artificially ventilated rats. EAS was applied to the abdominal area or to a hindpaw for 30 s at stimulus intensities of 0.1-10.0 mA with a stimulus frequency of 20 Hz. The duodenal motility was measured using the balloon method at a position about 1.5 cm caudal from the pylorus. Duodenal motility was inhibited by EAS at intensities of more than 5.0 mA (suprathreshold of group IV afferent excitation) when applied to the abdominal area. The duodenal inhibitory response existed after bilateral vagotomy or spinal transection, but was abolished by sectioning bilateral splanchnic nerves. Duodenal motility was facilitated by EAS at intensities of more than 2.0 mA (subthreshold of group IV, and suprathreshold for groups II+III afferent excitation) when applied to a hindpaw. The duodenal facilitatory response by EAS to a hindpaw existed after sectioning the splanchnic nerves, but disappeared after bilateral vagotomy or spinal transection. Furthermore, repetitive electrical stimulation of vagal efferent nerves enhanced duodenal motility, while repetitive electrical stimulation of the splanchnic efferent nerves inhibited the motility. It was concluded that the inhibitory response of duodenal motility elicited by EAS to the abdominal area is a spinal reflex response involving splanchnic inhibitory efferent nerves, and the enhanced response of duodenal motility by EAS to a hindpaw is a supraspinal reflex response involving vagal excitatory nerves.  相似文献   
36.
The transthyretin (TTR) gene is mainly expressed in the liver and choroid plexus of the brain. Most cases of familial amyloidotic polyneuropathy (FAP) are caused by TTR gene mutations, and characterized by amyloid deposition in the peripheral nervous system. We hypothesized that the TTR gene may be expressed in the peripheral nervous system. We analyzed TTR gene expression in several parts of the human, mouse and rat peripheral nervous systems using RT-PCR. To determine the sites of TTR synthesis in the dorsal root ganglia (DRG), mouse DRG were examined by in situ hybridization, laser capture microdissection and RT-PCR, and immunohistochemistry. TTR mRNA was detected in the DRG and cauda equina of humans and rodents by RT-PCR. TTR mRNA was not detected in the sural nerve, lumbar plexus or sympathetic ganglia in humans, or in the sciatic nerve in rodents. In mouse DRG, TTR mRNA was localized in the peripheral glial cells. No TTR-like immunoreactivity was observed in these tissues except for the perineurium. The TTR gene is probably expressed in the peripheral glial cells of the DRG. TTR synthesis in the DRG may be important for the involvement of the peripheral nervous system in FAP.  相似文献   
37.
38.
Granulocytopenia is commonly observed in interferon-alpha (IFN-alpha) therapy. Granulocyte colony-stimulating factor (G-CSF) has been identified as a primary cytokine that regulates neutrophil production, but the kinetics of G-CSF in IFN-alpha-induced granulocytopenia remains unclear. We investigated the effects of IFN-alpha on serum G-CSF levels and peripheral neutrophil counts (NC) in 15 chronic hepatitis C patients treated with standard-dose (10 MU) recombinant IFN-alpha for 24 weeks by using a chemiluminescent enzyme immunoassay for G-CSF. The time course of change after a single IFN-alpha injection showed that mean serum G-CSF levels and NC increased significantly compared with pretreatment values (p < 0.05), and were statistically correlated (r = 0.914, p = 0.0015). On repeating IFN-alpha administration, this change gradually became unclear, and granulocytopenia occurred, accompanied by a significant increase in serum G-CSF (p < 0.01). Both values reached a plateau within 2 weeks after starting treatment, and recovered rapidly after the cessation of therapy. Although continuous administration of IFN-alpha caused a time-dependent granulocytopenia, our results suggest that a single injection of IFN-alpha would be a potent inducer of G-CSF and NC in vivo as a short-term effect and that there would be negative-feedback regulation between them during long-term IFN-alpha therapy.  相似文献   
39.
A 2-month-old female infant with a retroperitoneal neuroblastoma on the left side was admitted to Niigata University Hospital. Her systolic blood pressure, as high as 220 mmHg, was attributed to renovascular hypertension because the plasma renin activity was increased up to 208 ng/ml per hour. Excision of the tumor, including the left kidney, and periaortic lymphnode dissection were performed. For safety during the lymphadenectomy, Nelaton catheters were placed around the inferior vena cava, aorta, superior mesenteric artery, and right renal artery. On the 2nd postoperative day anuria was noted, and aortography was performed revealing obstruction of the right renal artery, inferior mesenteric artery, and left common iliac artery. Thrombectomy via aortic incision was performed immediately to restore the blood flow. The patient developed chronic renal failure, however, and still requires hemodialysis or peritoneal dialysis. Pediatric surgeons should bear in mind that extensive periaortic lymphadenectomy may cause postoperative arterial thrombosis.  相似文献   
40.
To evaluate late results in children who had been treated with an internal drainage procedure for a choledochal cysts, we carried out follow-up examinations and performed endoscopic retrograde cholangiopancreatography (ERCP). Internal drainage procedures were performed on a total of 17 patients prior to 1972. The follow-up period ranged from 18 to 30 years. ERCP was performed on 8 of 10 patients followed up. All had dilatation of the common bile duct; 7 had an anomalous pancreatobiliary junction; and there were no carcinomas detected. The procedures consisted of choledochocystoduodenostomy (CCD) in 12 patients, choledochocystojejunostomy (Roux-Y) (CCJRY) in 4, and cholecystoduodenostomy (CYD) in 1. Of the 12 patients who were treated with CCD, 3 were lost to follow-up, 3 died of liver cirrhosis, and 6 survived. Five of the 6 surviving patients needed a reoperation for cholangitis; in 1 of these severe atypical abnormalities of the cyst were found on pathologic examination. Of the 4 patients who were treated with CCJRY, 1 died of liver cirrhosis but the 3 survivors had an asymptomatic postoperative course common bile duct and an anomalous pancreatobiliary junction noted during the current work-up. The patient who was treated with CYD needed another operation for choledocholithiasis. Our conclusions for following patients who were treated with an internal drainage procedure in childhood are twofold: (1) for patients who had CCD, cyst excision is recommended; and (2) for patients who had CCJRY performed at the age of 10 years or less, cautious observation is recommended as long as the patient remains asymptomatic. Offprint requests to: Masafumi Naito  相似文献   
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