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91.
ABSTRACT: BACKGROUND: BRAF inhibitors such as vemurafenib are a new family of biological drugs, recently available to treat metastatic malignant melanoma. METHODS: We present the case of a 38-year-old man affected by metastatic melanoma who had been under treatment with vemurafenib for a few days. The patient suffered from sudden onset of abdominal pain due to intra-abdominal hemorrhage with profuse hemoperitoneum. An emergency abdominal sonography confirmed the clinical suspicion of a splenic rupture. RESULTS: The intraoperative finding was hemoperitoneum due to splenic two-step rupture and splenectomy was therefore performed. Histopathology confirmed splenic hematoma and capsule laceration, in the absence of metastasis. CONCLUSIONS: This report describes the occurrence of a previously unreported adverse event in a patient with stage IV melanoma receiving vemurafenib.  相似文献   
92.
A genome-wide association study in Japan identified the C-C chemokine receptor type 6 gene (CCR6) as associated with rheumatoid arthritis (RA). This finding has not been validated in other Asian populations. A case-control study involving 996 subjects, comprising 440 controls and 556 RA patients, was done to determine their anticyclic citrullinated peptide (anti-CCP) antibody status and CCR6 polymorphism (rs3093024) genotype. Three hundred eighty-seven patients were anti-CCP positive and 153 anti-CCP negative. Logistic regression showed that allele A was likely to increase the risk of developing RA among females via a recessive model (odds ratio [OR]=1.55, 95% confidence interval [CI]=1.01, 2.39), whereas the risk effect appeared to be reduced among males via an additive model (OR=0.60, 95% CI=0.42, 0.85). Considering only subjects who are anti-CCP positive, allele A increased RA risk among females via a recessive model (OR=1.68, 95% CI=1.07, 2.64) but decreased the risk among males via an additive model (OR=0.59, 95% CI=0.39, 0.89). We showed that CCR6 polymorphism was a risk factor among females but a protective factor among males. Functional studies are warranted to unravel the pathophysiological relevance of the gene variant and other linked variants with RA.  相似文献   
93.
Objective To assess the incidence, cofactors, and excess risk of development of non-alcoholic fatty liver disease, including non-alcoholic steatohepatitis, attributable to tamoxifen in women.Design Prospective, randomised, double blind, placebo controlled trial.Setting and participants 5408 healthy women who had had hysterectomies, recruited into the Italian tamoxifen chemoprevention trial from 58 centres in Italy.Intervention Women were randomly assigned to receive tamoxifen (20 mg daily) or placebo for five years.Main outcome measure Development of non-alcoholic fatty liver disease in all women with normal baseline liver function who showed at least two elevations of alanine aminotransferase (≥ 1.5 times upper limit of normal) over a six month period.Results During follow up, 64 women met the predefined criteria: 12 tested positive for hepatitis C virus, and the remaining 52 were suspected of having developed non-alcoholic fatty liver disease (34 tamoxifen, 18 placebo)—hazard ratio = 2.0 (95% confidence interval 1.1 to 3.5; P = 0.04). In all 52 women ultrasonography confirmed the presence of fatty liver. Other factors associated with the development of non-alcoholic fatty liver disease included overweight (2.4, 1.2 to 4.8), obesity (3.6, 1.7 to 7.6), hypercholesterolaemia (3.4, 1.4 to 7.8), and arterial hypertension (2.0, 1.0 to 3.8). Twenty women had liver biopsies: 15 were diagnosed as having mild to moderate steatohepatitis (12 tamoxifen, 3 placebo), and five had fatty liver alone (1 tamoxifen, 4 placebo). No clinical, biochemical, ultrasonic, or histological signs suggestive of progression to cirrhosis were observed after a median follow up of 8.7 years.Conclusions Tamoxifen was associated with higher risk of development of non-alcoholic steatohepatitis only in overweight and obese women with features of metabolic syndrome, but the disease, in both the tamoxifen and the placebo group, after 10 years of follow up seems to be indolent.  相似文献   
94.
95.
High-performance liquid chromatography (HPLC), nano-HPLC, capillary electrochromatography (CEC) and on-line HPLC–atmospheric pressure chemical ionization mass spectrometry (APCI-MS) techniques were used for the identification and detailed characterization of two new metabolites of the former sedative drug thalidomide (TD). The advantages of nano-HPLC and CEC are higher peak efficiency and a drastic decrease in the analysis time, which, together with lower sample dilution during the analyses, allowed to obtain a detection sensitivity that was comparable to HPLC with common-sized columns. Both, nano-HPLC and CEC could be realized in the commercially available capillary electrophoresis system HP3D. On-line HPLC–APCI-MS coupling is a very useful technique for the rapid identification of metabolites without any need for reference compounds.  相似文献   
96.
S Rasmussen  RA Dixon 《The Plant cell》1999,11(8):1537-1552
3H-l-Phenylalanine is incorporated into a range of phenylpropanoid compounds when fed to tobacco cell cultures. A significant proportion of (3)H-trans-cinnamic acid formed from (3)H-l-phenylalanine did not equilibrate with exogenous trans-cinnamic acid and therefore may be rapidly channeled through the cinnamate 4-hydroxylase (C4H) reaction to 4-coumaric acid. Such compartmentalization of trans-cinnamic acid was not observed after elicitation or in cell cultures constitutively expressing a bean phenylalanine ammonia-lyase (PAL) transgene. Channeling between PAL and C4H was confirmed in vitro in isolated microsomes from tobacco stems or cell suspension cultures. This channeling was strongly reduced in microsomes from stems or cell cultures of transgenic PAL-overexpressing plants or after elicitation of wild-type cell cultures. Protein gel blot analysis showed that tobacco PAL1 and bean PAL were localized in both soluble and microsomal fractions, whereas tobacco PAL2 was found only in the soluble fraction. We propose that metabolic channeling of trans-cinnamic acid requires the close association of specific forms of PAL with C4H on microsomal membranes.  相似文献   
97.
The immunologically detected neuropeptides methionine enkephalin (ME), substance P (SP), beta-endorphin (beta-End), and alpha-melanocyte stimulating hormone (alpha-MSH) were purified from bovine corneal extracts by gradient, followed by isocratic, reversed phase-high performance liquid chromatography (RP-HPLC) and characterized, after both chromatographic steps, by radioimmunoassay (RIA). Immunologically detected ME and SP were purified from canine corneal extracts by gradient RP-HPLC and characterized by RIA. An anatomical study of the bovine cornea separated the cornea into an epithelium-enriched and a stroma-enriched portion. After gradient RP-HPLC, RIA demonstrated that all the ME-like immunoreactivity was located in the corneal epithelium, whereas the SP-like immunoreactivity was distributed between the stroma and epithelium in an approximate two-to-one ratio.  相似文献   
98.
Three roselle, Hibiscus sabdariffa L. varieties (Sudani, Masri and White) were cultivated at three different locations to recognize the transportation ability of roselle cultivation from the narrow old valley land to broad new land in Egypt. Qena as origin in situ old land, El-Kanater as ex situ old land and Nubaria as ex situ new land were the considered locations. Six growth quantitative characters and bolls infestation by spiny bollworm, Earias insulana were evaluated. Growth characters of roselle plants were affected significantly by either variety or location. Qena region was more suitable for roselle plant growth as judged with plant height, number of branches, number of fruits and sepals dry weight, followed by Nubaria followed by El-Kanater. Whereas, plants grown at Nubaria produced more fresh sepals weight than Qena or El-Kanater grown plants. As for Sudani, Nubaria exhibited the tallest plants, with the highest number of fruits and the heaviest fresh sepals as compared with the corresponding plants in Qena or El-Kanater. Values of broad sense heritability were highest for all characters in Qena. While the number of fruits per plant had the highest heritability in all locations. Dry sepals yield had highly significant correlation with all studied characters except percentage of water loss in Qena and Nubaria. Path coefficient analysis confirmed that fresh sepals yield had the highest direct and indirect effects on dried sepals yield. Chemical constituents responsible to sepal quality tended to produce significant variations due to the changes in varieties or locations. The highest levels of anthocyanins and sugars were achieved by Sudani variety, but the highest levels of free amino acids and total soluble solids were recorded for Masri variety. Moreover, Nubaria region was the most favourable for the accumulation of more anthocyanins in the sepals of all varieties followed by Qena. Plants grown at Qena produced sepals with the highest levels of sugars, free amino acids, organic acids and total soluble solids, followed by Nubaria followed by El-Kanater plants. Infestation with spiny bollworm Earias insulana was increased from Sudani up to Masri up to White varieties. Plants grown at Nubaria had the lowest number of attacks by bolls in all varieties, followed by those at El-Kanater followed by Qena plants. Spiny bollworm infestation was positively correlated with the number of branches and dry sepals weight, but negatively correlated with sepal moisture loss and anthocyanin contents. These findings clearly indicated that the Nubaria region was considered as a promising reclaimed area suitable for roselle cultivation, especially for Sudani, the most economic variety.  相似文献   
99.
We report the design, construction and use of an antibody bacteriophage display library built on the scaffold of a single-chain variable fragment (scFv) previously proven to be functionally expressed in the reducing environment of both bacterial and plant cytoplasm and endowed with intrinsic high thermodynamic stability. Four amino acid residues of the third hypervariable loop (CDR3) of both VH and VL were combinatorially mutated, generating a repertoire of approximately 5x10(7) independent scFvs, cloned in a phagemid vector. The ability of the antibody phage library to yield specific binders was tested by biopanning against several antigens. Successful selection of fully active scFvs was obtained, confirming the notion that combinatorial mutagenesis of few amino acid residues centrally located in the antigen-binding site is sufficient to provide binding specificities against virtually any target. High yields of both soluble and phage antibodies were obtained in Escherichia coli. Maintenance of the cognate scFv antibody stability in the newly selected scFv fragments was demonstrated by guanidinium chloride denaturation/renaturation studies and by soluble antibody expression in the bacterial cytoplasm. The antibody library described here allows the isolation of new stable binding specificities, potentially exploitable as immunochemical reagents for intracellular applications.  相似文献   
100.
Concentration changes of methionine enkephalin-like immjnoreactivity (ME-li) and -endorphin-like immunoreactivity (BE-li) in the rat pituitary following diffuse brain injury were studied. Closed head injury was induced by a weight-drop trauma device (450 g×2 m). The level of closed head injury used in this study altered the pituitary opioid peptide concentrations. The level of ME-li did not change in the experimental groups 3 hours, 10 hours, 24 hours, and 3 days after the trauma, but significantly increased by 34% 10 days after the trauma. BE-li remained constant 3 hours and 10 hours following the injury, increased by 48% at 24 hours, and remained at this level for 10 days after the trauma (44% at 3 days, and 40% at 10 days). The levels of ME-li and BE-li in the control sham-operated rats did not change during these times. The present measurements of BE-li and ME-li in the pituitary indicate that the opioid peptides that derive from two different neuropeptidergic systems, proopiomelanocortin (POMC) and preproenkephalin A, respectively, may participate in the pathophysiology of a closed head injury.  相似文献   
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