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991.
We evaluated the clinical efficacy and safety of tamsulosin hydrochloride and cernitin pollen extract in 243 patients with urinary disturbance associated with benign prostatic hyperplasia. They were assigned randomly to 3 groups, oral tamsulosin hydrochloride, cernitin pollen extract and their combination were administered for 12 weeks. The international prostate symptom score, post-voided residual urine and uroflowmetrogram were obtained before and after treatment. The international prostate symptom score improved in each group and then the maximum flow rate and average flow rate also increased significantly in the tamsulosin hydrochloride-administered groups. In conclusion, the administration of only tamsulosin hydrochloride and the combination of tamsulosin hydrochloride and cernitin pollen extract seemed more effective then the administration of only cernitin pollen extract in the treatment of urinary disturbance associated with benign prostatic hyperplasia.  相似文献   
992.
A 26-year-old woman presented with pain in the left hypochondrium, for which pancreatectomy and splenectomy was performed, with total gross excision of a mass. A tumor measuring 11 × 9 cm was found in the pancreas. On cut surface there were two cysts filled with a necrotic substance and hemorrhagic content. Spindle or ovoid-shaped cells, in the sarcomatous component, had diffusely infiltrated along the inner side of the walls of one cyst. Osteoclast-like giant cells (OGC) were also contained in the sarcomatous component. Adenoma components of mucinous epithelium with foci of borderline and adenocarcinomatous components were seen on the inner side of the other cyst. An ovarian-type stroma beneath the epithelial component was seen in the cyst wall. A diagnosis of undifferentiated carcinoma with OGC arising in a mucinous cystic neoplasm (MCN) of the pancreas, was made. Seven months after the initial operation the patient had a local recurrence, and the tumor was removed. One month after the second operation, the patient was free of symptoms. Only four cases of undifferentiated carcinoma with OGC arising in MCN, involving an ovarian-type stroma of the pancreas, have been reported.  相似文献   
993.
In this report, we describe a case of phyllodes tumor of the prostate with a high value of prostate-specific antigen (PSA). A 47-year-old man with symptoms of hematospermia presented with a steadily elevated serum PSA value of 60.76 ng/mL (normal range, < 4 ng/mL). A needle biopsy revealed atypical stromal cells without any evidence of malignancy. After radical prostatectomy, the tumor measured 2.9 cm in diameter and consisted of a single nodule composed of irregular, elongated epithelial ducts and atypical stromal cells with enlarged, occasionally multinucleated, pleomorphic, or hyperchromatic nuclei. Immunohistochemistry showed that the atypical stromal cells were positive for vimentin, androgen receptor, estrogen receptor, progesterone, and 5α-reductase, but negative for MIB-1, PSA, SMA, p53, desmin, CD34, c-kit, CD10, S-100, and EGFR. Excess PSA might be secreted by hyperplastic luminal cells driven by 5α-reductase-positive stromal and epithelial cells. Array-comparative genomic hybridization (array CGH) for genomic alterations revealed a gain of 11p13, which includes the WT1 gene, and a loss of 1p36.23 and 12p12.1. After surgery, the serum PSA value rapidly decreased to within the normal range; no recurrence or distant metastasis was noted after 2 years of follow up.  相似文献   
994.
There are few reports on HIV-1 intra-host evolutionary rate in asymptomatic treatment-naïve patients. Here, the HIV-1 intra-host evolutionary rate was estimated based on HIV-1 RNA sequences from plasma samples of blood donors in Japan. Blood donors were assumed to have received no treatment for and have no symptoms of HIV-1 infection because they were healthy, and declared no risky behaviors of HIV-1 infection on a self-reported questionnaire or interview followed by donation. HIV-1 RNA was obtained from 85 plasma samples from 36 blood donors who donated blood multiple times and were HIV-1-positive. The C2V3C3 region which encodes for a part of the envelope protein, and the V3 loop in the C2V3C3 region were analyzed by RT-PCR and direct sequencing, and the sequences were compared. The nucleotide substitution rate was calculated by linear regression. All HIV-1 samples analyzed were classified as subtype B. The mean nucleotide substitution rate in C2V3C3 was calculated to be 6.2?×?10?3–1.8?×?10?2/site/year (V3: 4.5?×?10?3–2.3?×?10?2/site/year). The mean non-synonymous substitution rate in C2V3C3 was calculated to be 5.2?×?10?3–1.7?×?10?2/site/year (V3: 4.5?×?10?3–2.1?×?10?2/site/year). The mean synonymous substitution rate in C2V3C3 was calculated to be 1.1?×?10?4–2.3?×?10?3/site/year (V3: 2.9?×?10?3/site/year). Among HIV-1 subtype B RNA-positive blood donors in Japan, the nucleotide substitution rate in C2V3C3 was estimated to be higher than that of reported cases using HIV-1 samples mainly obtained from AIDS patients. Compared to AIDS patients, immune responses against HIV-1 are probably more effective in HIV-1 RNA-positive blood donors. Consequently, immune pressure presumably promotes mutation of the virus genome.  相似文献   
995.
Proteasome‐mediated proteolysis is responsible for the generation of immunogenic epitopes presented by MHC class I molecules, which activate antigen‐specific CD8+ T cells. Immunoproteasomes, defined by the presence of the three catalytic subunits LMP2, MECL‐1, and LMP7, have been hypothesized to optimize MHC class I antigen processing. In this study, we demonstrate that the infection of mice with a protozoan parasite, Toxoplasma gondii, induced the expression of LMP7 mRNA in APC and increased the capacity of APC to induce the production of IFN‐γ by antigen‐specific CD8+ T cells. In vitro infection of a DC cell line with T. gondii also induced the expression of LMP7 and resulted in enhanced proteasome proteolytic activity. Finally, mice lacking LMP7 were highly susceptible to infection with T. gondii and showed a reduced number of functional CD8+ T cells. These results demonstrate that proteasomes containing LMP7 play an indispensable role in the survival of mice infected with T. gondii, presumably due to the efficient generation of CTL epitopes required for the functional development of CD8+ T cells.  相似文献   
996.
Silk proteins self-assemble into mechanically robust material structures that are also biodegradable and non-cytotoxic, suggesting utility for gene delivery. Since silk proteins can also be tailored in terms of chemistry, molecular weight and other design features via genetic engineering, further control of this system for gene delivery can be considered. In the present study, silk-based block copolymers were bioengineered with poly(l-lysine) domains for gene delivery. Ionic complexes of these silk-polylysine based block copolymers with plasmid DNA (pDNA) were prepared for gene delivery to human embryonic kidney (HEK) cells. The material systems were characterized by agarose gel electrophoresis, atomic force microscopy, and dynamic light scattering. The polymers self-assembled in solution and complexed plasmid DNA through ionic interactions. The pDNA complexes with 30 lysine residues prepared at a polymer/nucleotide ratio of 10 and with a solution diameter of 380 nm showed the highest efficiency for transfection. The pDNA complexes were also immobilized on silk films and demonstrated direct cell transfection from these surfaces. The results demonstrate the potential of bioengineered silk proteins as a new family of highly tailored gene delivery systems.  相似文献   
997.
OBJECTIVE: Recent studies in the United States support the protective effect of estrogen use on tooth retention; however, little is known as to how estrogen promotes tooth retention. The aims of this study were to investigate the effects of estrogen use on tooth retention, oral bone height, and oral bone porosity in Japanese postmenopausal women and to clarify how estrogen promotes tooth retention. DESIGN: Relationships among the number of teeth remaining (total, anterior, and posterior teeth), oral bone height, oral bone porosity, bone mineral density of the lumbar spine and the femoral neck, estrogen use status, and the duration of estrogen use were evaluated in 330 Japanese postmenopausal women (mean age +/- SD, 56.8 +/- 7.6 y). RESULTS: Analysis of covariance adjusted for confounding variables revealed that estrogen users (66 women) tended to have more posterior teeth than did nonusers (264 women) (P = 0.065), although there were no significant differences in number of total (P = 0.196) and anterior (P = 0.751) teeth remaining, oral bone height (P = 0.970), oral bone porosity (P = 0.745), and bone mineral density of the lumbar spine (P = 0.459) and the femoral neck (P = 0.749) between estrogen users and nonusers. Multiple regression analysis showed that the duration of estrogen use was significantly associated with number of total (P = 0.019) and posterior (P = 0.007) teeth remaining, independent of age and oral bone height. CONCLUSION: Our results suggest that estrogen may promote tooth retention by strengthening the periodontal attachment surrounding the teeth, but not increasing oral bone height and not decreasing oral bone porosity.  相似文献   
998.
We here describe a case of congenital leukemia that ended in intrauterine fetal demise at 30 weeks of gestation. Acute enlargement of the fetal trunk, elevated pulsatility index of the umbilical artery with concomitant decline of pulsatility index of the middle cerebral artery, pleural effusion, and polyhydramnios preceded the fetal death. Diagnosis of congenital myeloid leukemia was suggested by microscopic examination of the placental tissue, revealing immature myeloid precursors filling the lumina of fetal vessels in the umbilical cord and chorionic villi. Extensive vascular involvement of the placenta by leukemic cells was considered to be a primary cause of the fetal death.  相似文献   
999.
Poly(ethylene glycol) (PEG) modification onto a gene delivery carrier for systemic application results in a trade-off between prolonged blood circulation and promoted transfection because high PEG shielding is advantageous in prolonging blood retention, while it is disadvantageous with regard to obtaining efficient transfection owing to hampered cellular uptake. To tackle this challenging issue, the present investigation focused on the structure of polyplex micelles (PMs) obtained from PEG–poly(l-lysine) (PEG–PLys) block copolymers characterized as rod-shaped structures to seek the most appreciable formulation. Comprehensive investigations conducted with particular focus on stability, PEG crowdedness, and rod length, controlled by varying PLys segment length, clarified the effect of these structural features, with particular emphasis on rod length as a critical parameter in promoting cellular uptake. PMs with rod length regulated below the critical threshold length of 200 nm fully exploited the benefits of cross-linking and the cyclic RGD ligand, consequently, exhibiting remarkable transfection efficiency comparable with that of ExGen 500 and Lipofectamine® LTX with PLUS™ even though PMs were PEG shielded. The identified PMs exhibited significant antitumor efficacy in systemic treatment of pancreatic adenocarcinoma, whereas PMs with rod length above 200 nm exhibited negligible antitumor efficacy despite a superior blood circulation property, thereby highlighting the significance of controlling the rod length of PMs to promote gene transduction.  相似文献   
1000.
CRISPR‐Cas9‐mediated genome‐editing technology contributes not only to basic genomic studies but also to clinical studies such as genetic correction and virus inactivation. Hepatitis B virus (HBV) is a major target for potential application of CRISPR‐Cas9 in eliminating viral DNA from human cells. However, the high stability of covalently closed circular DNA (cccDNA) makes it difficult to completely clear HBV infection. Here, we report highly multiplexed CRISPR‐Cas9‐nuclease and Cas9‐nickase vector systems that simultaneously target three critical domains of the HBV genome. Co‐transfection of an HBV‐expressing plasmid and all‐in‐one CRISPR‐Cas9 vectors resulted in significant reduction in viral replicative intermediates and extracellular hepatitis B surface and envelope antigens. In addition, successful fragmentation of the HBV genome was confirmed by DNA sequencing. Despite its high efficacy in suppressing HBV, no apparent off‐target mutations were detected by genomic cleavage detection assay and the small number of observed mutations was extremely rare and could only be detected by deep sequencing analysis. Thus, our all‐in‐one CRISPR‐Cas9‐nuclease and Cas9‐nickase vectors present a model for simultaneous targeting of multiple HBV domains, potentially contributing to a well‐designed therapeutic approach for curing HBV patients.  相似文献   
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