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101.
Perception of salt stress in plant cells induces a change in the free cytosolic Ca2+, [Ca2+]cyt, which transfers downstream reactions toward salt tolerance. Changes in cytosolic H+ concentration, [H+]cyt, are closely linked to the [Ca2+]cyt dynamics under various stress signals. In this study, salt‐induced changes in [Ca2+]cyt, and [H+]cyt and vacuolar [H+] concentrations were monitored in single protoplasts of rice (Oryza sativa L. indica cvs. Pokkali and BRRI Dhan29) by fluorescence microscopy. Changes in cytosolic [Ca2+] and [H+] were detected by use of the fluorescent dyes acetoxy methyl ester of calcium‐binding benzofuran and acetoxy methyl ester of 2′, 7′‐bis‐(2‐carboxyethyl)‐5‐(and‐6) carboxyfluorescein, respectively, and for vacuolar pH, fluorescent 6‐carboxyfluorescein and confocal microscopy were used. Addition of NaCl induced a higher increase in [Ca2+]cyt in the salt‐tolerant cv. Pokkali than in the salt‐sensitive cv. BRRI Dhan29. From inhibitor studies, we conclude that the internal stores appear to be the major source for [Ca2+]cyt increase in Pokkali, although the apoplast is more important in BRRI Dhan29. The [Ca2+]cyt measurements in rice also suggest that Na+ should be sensed inside the cytosol, before any increase in [Ca2+]cyt occurs. Moreover, our results with individual mesophyll protoplasts suggest that ionic stress causes an increase in [Ca2+]cyt and that osmotic stress sharply decreases [Ca2+]cyt in rice. The [pH]cyt was differently shifted in the two rice cultivars in response to salt stress and may be coupled to different activities of the H+‐ATPases. The changes in vacuolar pH were correlated with the expressional analysis of rice vacuolar H+‐ATPase in these two rice cultivars.  相似文献   
102.
Retrieval of foreign bodies from the genitourinary system, most commonly inserted for sexual satisfaction or as a result of a psychiatric illness, can pose a significant surgical challenge. Due to their breadth of size, shape, and location within the genitourinary system, endoscopic management can be difficult. Here, we review the management of four cases of foreign object insertion into the genitourinary system and their outcomes and management.Key words: Foreign body insertion, Sounding, Genitourinary foreign object, Endoscopic extractionForeign objects within the genitourinary tract present a challenging urologic finding due to the diversity and breadth of presentation. Although many objects are easily removed, more complex approaches may be required depending on the size, shape, and location of the object.1,2 In this case series, we discuss the endoscopic management of four patients who presented with foreign bodies in the urethra. Two patients inserted beads into their genitourinary tract for the purpose of sexual stimulation and two patients had a history of psychiatric illness with multiple insertions of a diverse range of foreign objects. In all four cases, endoscopic management was successful in removing the objects, with no need for an open approach such as perineal urethrotomy or open cystostomy. In case 2, in which an open approach was attempted at an outside hospital, this open approach was associated with intraoperative complications.  相似文献   
103.
Suppressor of cytokine signaling (SOCS)-1 protein modulates signaling by IFN-gamma by binding to the autophosphorylation site of JAK2 and by targeting bound JAK2 to the proteosome for degradation. We have developed a small tyrosine kinase inhibitor peptide (Tkip) that is a SOCS-1 mimetic. Tkip is compared in this study with the kinase inhibitory region (KIR) of SOCS-1 for JAK2 recognition, inhibition of kinase activity, and regulation of IFN-gamma-induced biological activity. Tkip and a peptide corresponding to the KIR of SOCS-1, ((53))DTHFRTFRSHSDYRRI((68)) (SOCS1-KIR), both bound similarly to the autophosphorylation site of JAK2, JAK2(1001-1013). The peptides also bound to JAK2 peptide phosphorylated at Tyr(1007), pJAK2(1001-1013). Dose-response competitions suggest that Tkip and SOCS1-KIR similarly recognize the autophosphorylation site of JAK2, but probably not precisely the same way. Although Tkip inhibited JAK2 autophosphorylation as well as IFN-gamma-induced STAT1-alpha phosphorylation, SOCS1-KIR, like SOCS-1, did not inhibit JAK2 autophosphorylation but inhibited STAT1-alpha activation. Both Tkip and SOCS1-KIR inhibited IFN-gamma activation of Raw 264.7 murine macrophages and inhibited Ag-specific splenocyte proliferation. The fact that SOCS1-KIR binds to pJAK2(1001-1013) suggests that the JAK2 peptide could function as an antagonist of SOCS-1. Thus, pJAK2(1001-1013) enhanced suboptimal IFN-gamma activity, blocked SOCS-1-induced inhibition of STAT3 phosphorylation in IL-6-treated cells, enhanced IFN-gamma activation site promoter activity, and enhanced Ag-specific proliferation. Furthermore, SOCS-1 competed with SOCS1-KIR for pJAK2(1001-1013). Thus, the KIR region of SOCS-1 binds directly to the autophosphorylation site of JAK2 and a peptide corresponding to this site can function as an antagonist of SOCS-1.  相似文献   
104.
In the current study, a series of pyrazole-sulfonamide derivatives (2–14) were synthesized, characterized, and the inhibition effects of the derivatives on human carbonic anhydrases (hCA I and hCA II) were investigated as in vitro. Structures of these sulfonamides were confirmed by FT-IR, 1H NMR, 13C NMR and LC–MS analysis. 1H NMR and 13C NMR revealed the tautomeric structures. hCA I and hCA II isozymes were purified from human erythrocytes and inhibitory effects of newly synthesized sulfonamides on esterase activities of these isoenzymes have been studied. The Ki values of compounds were 0.062–1.278 μM for hCA I and 0.012–0.379 μM for hCA II. The inhibition effects of 7 for hCA I and 4 for hCA II isozymes were almost in nanomolar concentration range.  相似文献   
105.
A major challenge for oncologists and pharmacologists is to develop less toxic drugs that will improve the survival of lung cancer patients. Frondoside A is a triterpenoid glycoside isolated from the sea cucumber, Cucumaria frondosa and was shown to be a highly safe compound. We investigated the impact of Frondoside A on survival, migration and invasion in vitro, and on tumor growth, metastasis and angiogenesis in vivo alone and in combination with cisplatin. Frondoside A caused concentration-dependent reduction in viability of LNM35, A549, NCI-H460-Luc2, MDA-MB-435, MCF-7, and HepG2 over 24 hours through a caspase 3/7-dependent cell death pathway. The IC50 concentrations (producing half-maximal inhibition) at 24 h were between 1.7 and 2.5 µM of Frondoside A. In addition, Frondoside A induced a time- and concentration-dependent inhibition of cell migration, invasion and angiogenesis in vitro. Frondoside A (0.01 and 1 mg/kg/day i.p. for 25 days) significantly decreased the growth, the angiogenesis and lymph node metastasis of LNM35 tumor xenografts in athymic mice, without obvious toxic side-effects. Frondoside A (0.1–0.5 µM) also significantly prevented basal and bFGF induced angiogenesis in the CAM angiogenesis assay. Moreover, Frondoside A enhanced the inhibition of lung tumor growth induced by the chemotherapeutic agent cisplatin. These findings identify Frondoside A as a promising novel therapeutic agent for lung cancer.  相似文献   
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108.
In this study, groups of B6C3F1 male mice were treated with dichloroacetate (DCA), trichloroacetate (TCA), and mixtures of the compounds (Mix I, II, and III) daily by gavage, for 13 weeks. The tested doses were 7.5, 15, and 30 mg DCA/kg/day and 12.5, 25, and 50 mg TCA/kg/day. The DCA: TCA ratios in Mix I, II, and III were 7.5:12.5, 15:25, and 30:50 mg/kg/day, respectively. Peritoneal lavage cells were collected at the end of the treatment period and assayed for the biomarkers of phagocytic activation, including superoxide anion and tumor necrosis factor‐alpha production, and myeloperoxidase activity. The mixtures produced nonlinear effects on the biomarkers of phagocytic activation, with Mix I and II effects were found to be additive, but Mix III effects were found to be less than additive. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:237‐242, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21476  相似文献   
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110.
Cryptosporidium , a protozoan parasite that causes watery diarrhea, is found worldwide and is common in areas with low water hygiene. In February 2014, 866 stool samples were collected from the inhabitants of 2 rural areas in White Nile State, Sudan. These stool samples were assessed by performing modified acid-fast staining, followed by examination under a light microscope. The overall positive rate of Cryptosporidium oocysts was 13.3%. Cryptosporidium oocysts were detected in 8.6% stool samples obtained from inhabitants living in the area having water purification systems and in 14.6% stool samples obtained from inhabitants living in the area not having water purification systems. No significant difference was observed in the prevalence of Cryptosporidium infection between men and women (14.7% and 14.1%, respectively). The positive rate of oocysts by age was the highest among inhabitants in their 60s (40.0%). These findings suggest that the use of water purification systems is important for preventing Cryptosporidium infection among inhabitants of these rural areas in Sudan.  相似文献   
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