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1.
A new two-step deprotection/cleavage procedure for t-butoxycarbonyl (Boc) based solid phase peptide synthesis is reported. First the protective groups are removed from 4-(oxymethyl)-phenylacetamidomethyl (PAM) resin attached peptide with the weak hard acid, trimethylsilyl bromide-thioanisole/trifluoroacetic acid (TFA). In the second step, the peptide is cleaved from the resin with a stronger hard acid such as trimethylsilvl trifluoromethanesulfonate in TFA or with HF. The method is also shown to deformylate Nin-formyltryptophan moiety efficiently. The usefulness of this procedure for practical solid phase peptide synthesis is demonstrated by comparison with other deprotection methods in the synthesis of urotensin II and human endothelin.  相似文献   
2.
To clarify the significance of basic fetoprotein (BFP) in lymphocytes, we investigated whether BFP is produced in lymphocytes during blastic transformation. Peripheral blood lymphocytes obtained from 14 adults were cultured under the stimulation of lectins. The concentration of BFP in the culture medium (extracellular BFP) was estimated serially. The incorporation of [6-3 H] thymidine was assayed simultaneously. The intracellular BFP was measured by dual flow cytometry for DNA and BFP. A lymph node was studies immunohistochemically. Serum BFP was measured in four cases of lumphocytic leukaemia. In two cases, dual staining was performed. The intracellular BFP of the mitogen-stimulated lymphocytes was increased within 24 h. The extracellular BFP was increased exponentially from 72 h. The extracellular BFP at 96 h did not correlate with the [3H]-thymidine incorporation. The intracellular BFP increase began in G1 phase. Immunostaining showed that the B cells also produced BFP. The
serum BFP level in leukaemia was high in 1 of 4 cases and the leukaemic cells in two cases showed high intracellular BFP content. These observations indicate that BFP is produced in activated human lymphocytes and in lymphocytic leukaemic cells. The production of BFP during blastic transformation will be a useful new in vitro model for studying the biological role of BFP, and BFP labelling may offer some new possibilities for study of lymphocytes.  相似文献   
3.
Summary. Background: C4b‐binding protein (C4BP), a multimeric protein structurally composed of α chains (C4BPα) and a β chain (C4BPβ), regulates the anticoagulant activity of protein S (PS). Patients with sepsis have increased levels of plasma C4BP, which appears to be induced by interleukin (IL)‐6. However, it is not fully understood how lipopolysaccharide (LPS) and IL‐6 affect the plasma C4BP antigen level and C4BPα and C4BPβ expression in hepatocytes. Objectives: To assess the effect of LPS and IL‐6 on plasma C4BP, PS–C4BP complex levels, PS activity, and C4BP expression by rat liver in vivo and on C4BP expression by isolated rat hepatocytes in vitro. Results: Plasma C4BP antigen level transiently decreased from 2 to 12 h after LPS (2 mg kg?1) injection, and then it abruptly increased up to 24 h after LPS injection. Plasma C4BP antigen level increased until 8 h after IL‐6 (10 μg kg?1) injection, and then gradually decreased up to 24 h after IL‐6 injection. LPS significantly decreased the protein and mRNA expression of both C4BPα and C4BPβ in rat hepatocytes, and this effect was inhibited by NFκB and MEK/ERK inhibitors. IL‐6 mediated increase in C4BPβ expression in rat hepatocytes, which leads to increased plasma PS–C4BP complex level and to decreased plasma PS activity, was inhibited by inhibition of STAT‐3. Conclusion: LPS decreases both C4BPα and C4BPβ expression via the NFκB and MEK/ERK pathways, whereas IL‐6 specifically increases C4BPβ expression via the STAT‐3 pathway, causing an increase in plasma PS–C4BP complex, and thus decreasing the anticoagulant activity of PS.  相似文献   
4.
A morphological approach to cell dynamics is usually difficult, since routine preparative techniques for electron microscopy always induce artifacts due to cessation of the blood supply into organs. An in vivo cryotechnique followed by the freeze-substitution method probably reduces such problems. It was applied for examining the pulmonary alveoli of BALB/c mice in vivo. The following ultrastructural features were revealed. (1) A surfactant layer provided a continuous covering to the alveolar epithelium. (2) Pleural epithelial cells, alveolar cells and endothelial cells contained many small vesicles and pits. In the alveolar epithelium, they were often localised near microtubules. (3) Typical lamellar structures in large alveolar epithelial cells were rarely detected. (4) Circulating erythrocytes with various shapes were observed in branching blood capillaries. (5) A close association between erythrocytes and the endothelium was seen at the peripheral alveolar septum. Such ultrastructural arrangements may be appropriate for the physiological functions of the pulmonary alveoli, such as exchanges of gases or materials in vivo.  相似文献   
5.
BACKGROUND: In an effort to improve the quality of life of children with cancer, this study analyzes the signs and symptoms at the end of life in such children. It is hoped that these data will contribute to the development of appropriate programs to address the challenges faced by these children. PROCEDURE: Between 1994 and 2000, 28 children died after treatment for cancer at Hamamatsu University Hospital, Japan. The circumstances, signs and symptoms at the end of life of these children were analyzed through their medical records. RESULTS: Of the 28 children, the underlying diseases were leukemia/lymphoma (LL group; n=11), brain tumors (BT group; n=7), and other solid tumors (OST group; n=10). Records showed poor appetite (100%), dyspnea (82.1%), pain (75.0%), fatigue (71.4%), nausea/vomiting (57.1%), constipation (46.4%) and diarrhea (21.4%) among these children. Anxiety was reported in 53.6% of the entire group of 28 children; however, no child in the BT group manifested anxiety. However, disturbance of consciousness was reported in all children in the BT group, which was significantly greater than in the other groups. Awareness, fear or acceptance of the imminence of his/her own death as indicated by verbal expression was reported in nine children (32.1%). CONCLUSIONS: Using the data obtained in the present study, we describe situations faced in the terminal care of children. It is important to address the problems revealed by this analysis in order to achieve improvements in both the physical and psychological care of children with terminal cancer.  相似文献   
6.
We studied T cell responses to four glutathione S transferase (GST)-fused mite antigens prepared in our laboratory using peripheral blood lymphocytes from mite-sensitive patients with bronchial asthma. Of the four recombinant antigens, purified GST-Mag3 had the strongest ability to cause patients' lymphocytes to proliferate, and its potency was almost comparable to that of crude mite bodies (Dfb) and faeces (Dff) antigens and a purified major antigen, Der f 2. The responder lymphocytes were mainly T cells, because the proliferative response was depleted by the treatment of lymphocytes with anti-CD3 antibody and complement, but not with anti-CD20 antibody and complement. The responsiveness of lymphocytes to GST-Mag3 correlated with that to Der f 2, but GST-Mag3 displayed slightly higher activity to stimulate lymphocytes than Der f 2. Simultaneously, the levels of Dff- and GST-Mag3-specific IgE antibodies correlated with the responsiveness of lymphocytes to GST-Mag3. These results suggest that Mag3 is a new valuable antigen for the response of T cell proliferation in mite-sensitive patients.  相似文献   
7.
Two autopsy cases of Cronkhite-Canada syndrome were reported. The caused of hypoproteinemia, electrolyte imbalance and ectodermal changes were discussed with reference to previously reported cases. The mechanism of protein loss was probably due to outflow into the intestinal lumen of the mucous substance in the cystically dilated glands, directly and/or indirectly followed by loss of mucosal surface. Electrolyte imbalance probably developed from gastrointestinal loss as well as poor substitution. The ectodermal changes were probably not a subsequent part of the emaciation or hypoproteinemis, but an inherent part of this disease. Therapy, whether substitution or surgical procedure, should be selected in order to control the general condition of the patient.  相似文献   
8.
The tetradecapeptide amide corresponding to the entire amino acid sequence of a wasp venom (polistes mastoparan), isolated from Polistes jadwagae, was synthesized using the trifluoroacetic acid-thioanisole deprotecting procedure.  相似文献   
9.
BACKGROUND: A school urinary screening (SUS) system has been conducted for 30 years in Japan, but the cross-sectional data have never been reported or analyzed. The purpose of the present study was to analyze the data epidemiologically. METHODS: All elementary and junior high school children in public school in Tokyo who had SUS performed by the Tokyo Health Service Association from 1974 to 2002 (approx. 400,000-600,000 children per year) were involved. The cross-sectional data were analyzed with Pearson's correlation coefficient. RESULTS: During the first 10 years of SUS, the prevalence of abnormal urinalysis in both the first and second screenings varied widely, and the result of the second screening was affected by that of the first screening. The results of both first and second screening were highly correlated with the prevalence of hematuria, especially microhematuria, in both elementary and junior high school children. They were also correlated with the prevalence of proteinuria in junior high school children. Important factors that affected the prevalence of hematuria and/or proteinuria were reagent strips and sampling method of urinalysis. CONCLUSIONS: In order to validate SUS, attention should be paid to quality controls of the screening method, such as the selection of reagent strips, and the participants should be instructed to strictly adhere to the sampling method.  相似文献   
10.
Abstract: In this study the definition of cardiac cancer (histologically adenocarcinoma) was taken to be a cancerous lesion, the size of which is less than 4 cm and the center of which is located within 2 cm from the esophagocardiac junction. 42 patients (0.8%) fit the above definition of cardiac cancer out of 4,958 patients with solitary gastric cancer operated on at the National Cancer Center Hospital daring the period between 1962 and 1988. The clinicopathological and endoscopic findings of these 42 patients were compared with those of 132 patients with gastric cancer located in the upper third of the stomach other than in the cardia (cancer in the other C-area). In the group with cardiac cancer, the male patients (M/F ratio: 3.7), the elderly patients (mean age: 61.3 years), a differentiated type of adenocarcinoma (90%), lesions located at the lesser curvature (62%) and the elevated type of lesion were found to predominate. The incidence of early cancer (60%) and the incidence of small lesions less than 2 cm (32%) in diameter were lower than in the patients with cancers in the other C-area. In the group with cardiac cancer, however, the incidence of such types of early cancer as the depressed lesion, a small lesion less than 2 cm in diameter and lesions difficult to diagnose endoscopically, have been increasing. In recent years, cardicac cancers have been found not only on the lesser curvature, but also in different areas of the cardia. These results suggest an improvement in endoscopic diagnosis for cardiac cancer. To make early detection more precise, it will be indispensable not to overlook even faint or indistinct mucosal abnormalities at the area adjacent to the esophagocardiac junction.  相似文献   
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