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991.
Complex regulation of T cell functions during pregnancy is required to ensure materno-fetal tolerance. Here we reveal a novel pathway for the temporary suppression of maternal T cell responses in uncomplicated human pregnancies. Our results show that arginase activity is significantly increased in the peripheral blood of pregnant women and remarkably high arginase activities are expressed in term placentae. High enzymatic activity results in high turnover of its substrate L-arginine and concomitant reduction of this amino acid in the microenvironment. Amino acid deprivation is emerging as a regulatory pathway of lymphocyte responses and we assessed the consequences of this enhanced arginase activity on T cell responses. Arginase-mediated L-arginine depletion induces down-regulation of CD3 zeta, the main signalling chain of the TCR, and functional T cell hyporesponsiveness. Importantly, this arginase-mediated T cell suppression was reversible, as inhibition of arginase activity or addition of exogenous L-arginine restored CD3 zeta chain expression and T cell proliferation. Thus, L-arginine metabolism constitutes a novel physiological mechanism contributing to the temporary suppression of the maternal immune response during human pregnancy.  相似文献   
992.
PURPOSE: The aim of this study was to demonstrate OK- 432 sclerotherapy efficacy for treatment of simple renal cysts. MATERIALS AND METHODS: Twenty patients with 25 symptomatic or large simple cysts were treated by ultrasonography (US)-guided percutaneous aspiration and injection of OK-432 (8 men and 12 women, mean age 63.6 years, SD 9.5). Six patients presented with flank pain, 14 presented with renal mass; renal cyst location was right, left, or bilateral sided in 9, 8, and 8 kidneys, respectively. Patients were evaluated by clinical assessment, US, or CT scan 3 months following the procedure. Complete and partial success was defined as symptom resolution with either total cyst ablation or greater than 70% reduction, respectively. Failure was defined as 30% of cyst size recurrence and/or persistent symptoms. RESULTS: Average reduction was 93.0%. Complete and partial resolution occurred in 11 (44.0%) and 13 (52.0%) cysts, respectively. One case was defined as failure, with a 64.2% size reduction from 10.9cm to 3.9cm (volume reduction rate 95.4%). Renal pain improved in all patients, regardless of complete or partial resolution. Minor complications occurred in 3 patients, 2 developed leukocytosis and 1 had mild fever (< 38.5 degrees C) following aspiration and sclerotherapy. Successful treatment was achieved with conservative measures and NSAID therapy. CONCLUSION: Percutaneous treatment of simple renal cysts with OK-432 sclerotherapy was found to be a safe, effective and minimally invasive procedure.  相似文献   
993.
This study was aimed to examine whether the changes of protein expression of sodium transporters in the ischemic penumbra are associated with the pathogenesis of ischemia-induced brain edema and/or brain cell injury. An experimental model of cerebral ischemia was made by permanent middle cerebral artery occlusion (pMCAO) in rats and the changes of protein expression of sodium transporters in the ischemic penumbra were examined by immunoblotting. Extensive infarction was observed in the frontal and parietal cortical and subcortical areas at 3 and 6h after pMCAO. Immunoblotting analyses revealed significantly increased expressions of electrogenic NBC (241 +/- 11% at 3 h and 154 +/- 9% at 6 h, P < 0.05) and NHE1 (144 +/- 3% at 3 h and 170 +/- 9% at 6 h, P < 0.05), compared with sham-operated controls. In contrast, Na-K-ATPase expression (78 +/- 6% at 3 h and 85 +/- 3% at 6 h, P < 0.05) was significantly decreased. The expression of NCX1 was unchanged at 3 h, but was significantly increased at 6 h (141 +/- 3%, P < 0.05). In addition, the expressions of neuronal (NeuN) and astroglial cell (GFAP) proteins were decreased, whereas the expression of oligodendrocyte protein (CNPase) was unchanged. Taken together, the selectively increased expressions of NHE1, electrogenic NBC, and NCX1 and decreased expression of Na-K-ATPase in the ischemic penumbra are likely to contribute to the secondary brain cell damages presumably through intracellular Na(+) accumulation, cell swelling, and intracellular Ca(2+) overload.  相似文献   
994.
Choi KS  Nah JJ  Ko YJ  Kim YJ  Joo YS 《Virus research》2007,123(2):216-218
The envelope (E) protein of WNV plays an important role in the virus neutralization. Using a mAb 5E8, a neutralizing epitope on the domain III of the E of the New York strain of WN virus was characterized. Results from neutralization-escape mutants and site-directed mutagenesis revealed that the 5E8 epitope is a highly conformation dependent epitope consisting of at least residues E330, E332 and E367 on the domain III. Besides known critical neutralizing epitopes E330 and E332, our results indicate that residue E367, a component of DE loop on the domain III, appeared to be associated with neutralization but little with neuroinvasion of the virus, as reported previously (Beasley et al., 2002).  相似文献   
995.
996.
997.
Liver abscesses are very rare complications of ulcerative colitis, and furthermore, there has been only one case of splenic abscess in a patient with ulcerative colitis reported in the English literature. We recently encountered a patient with ulcerative colitis accompanied by both hepatic and splenic abscesses. The patient was treated with abscess drainage as well as sulfasalazine and antibiotics. Follow-up sonography of the abdomen showed complete resolution of the lesions. To our knowledge, this is the first report of combined case of multiple liver abscesses combined with splenic abscess in a patient with ulcerative colitis.  相似文献   
998.
Syringocystadenocarcinoma papilliferum (SCACP) is a rare form of adenocarcinoma of the skin. This is the malignant counterpart of syringocystadenoma papilliferum (SCAP) and usually develops on the scalp in a long-standing lesion identified clinically as SCAP. We describe a 65-yr-old Korean man with a nodule on the right supra-pubic area with a 2-yr duration. Histologically this tumor had a similar overall configuration as in SCAP, but the tumor was asymmetric and poorly circumscribed, extending into the deep dermis and showed cytologic atypia. The tumor cells showed positive reaction to GCDFP-15, but negative reaction to CEA and HMFG-1. We established the diagnosis of SCACP in the patient, and a wide excision was performed to remove the tumor. The patient has been well without relapse or metastasis for 2 yr.  相似文献   
999.
Only a few reports have focused on ocular motor paralysis in herpes zoster ophthalmicus. We report a case of ocular motor paralysis resulting from herpes zoster. The patient, an 80-yr-old woman, presented with grouped vesicles, papules, and crusting in the left temporal area and scalp, with diplopia, impaired gaze, and severe pain. Her cerebrospinal fluid analysis was positive for varicellar zoster virus IgM. Magnetic resonance imaging was performed to rule out other diseases causing diplopia; there were no specific findings other than old infarctions in the pons and basal ganglia. Therefore, she was diagnosed of abducens nerve palsy caused by herpes zoster ophthalmicus. After 5 days of systemic antiviral therapy, the skin lesions improved markedly, and the paralysis was cleared 7 weeks later without extra treatment.  相似文献   
1000.
Progress in biomedical imaging depends on the development of probes that combine low toxicity with high sensitivity, resolution, and stability. Toward that end, a new class of highly fluorescent core-shell silica nanoparticles with narrow size distributions and enhanced photostability, known as C dots, provide an appealing alternative to quantum dots. Here, C dots are evaluated with a particular emphasis on in-vivo applications in cancer biology. It is established that C dots are nontoxic at biologically relevant concentrations, and can be used in a broad range of imaging applications including intravital visualization of capillaries and macrophages, sentinel lymph node mapping, and peptide-mediated multicolor cell labeling for real-time imaging of tumor metastasis and tracking of injected bone marrow cells in mice. These results demonstrate that fluorescent core-shell silica nanoparticles represent a powerful novel imaging tool within the emerging field of nanomedicine.  相似文献   
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