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1.
Twenty-four cases of trichotillomania attending psychiatry outpatient department and child guidance clinic at Kalawati Saran Children's and Smt Sucheta Kriplani Hospitals over a period of 2 years from July, 1985 to November 1987 were studied. Females (66.7%) outnumbered the males (33.3%). Majority of cases belonged to age group 6-10 years (54.2%) and nuclear family (68.5%). Nail-biting (25.0%) was the commonest associated neurotic trait, followed by enuresis (20.9%), temper-tantrum (12.5%), etc. A past history of hysterical fits and neurotic depression was found in 3 cases (12.5%) and 2 cases (8.3%) respectively. Family history of neurosis was seen in mothers and fathers of 20.9% and 12.5% cases respectively. Trichobezoars and trichophytobezoars were found in 6 cases (25.0%) and 3 cases (12.5%) respectively. Majority of patients of trichobezoars presented with vague complaints like heaviness in the stomach (55.6%), inability to gain weight (44.4%), etc, while 22.2% cases were asymptomatic and detected only on screening.  相似文献   
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Treatment of 32P-labeled rabbit platelets with platelet-activating factor (PAF) caused a time- and dose-dependent phosphorylation of several proteins including five major phosphorylated proteins with apparent molecular weights of 20,000, 35,000, 40,000, 65,000, and 150,000. Both PAF and thrombin caused a rapid increase followed by a decrease in phosphorylation of proteins, indicating the occurrence of a phosphorylation-dephosphorylation process. Four separate PAF receptor antagonists, CV-3988, CV-6209, SRI-63-441, and SRI-63-675 drastically reduced the PAF-stimulated protein phosphorylation. The order of potency was SRI-63675 greater than SRI-63441 greater than or equal to CV-6209 greater than CV-3988. These antagonists had no effect on thrombin-stimulated protein phosphorylation. Pretreatment of platelets with PAF (0.1 nM) completely abolished any further protein phosphorylation by the same concentration of PAF. PAF pretreatment shifted the dose response of protein phosphorylation by about 2 log units, to the right. When platelets were treated with PAF (10 nM) for 10 min, this abolished phosphorylation of proteins by any concentration of PAF. These studies indicated a homologous desensitization of protein phosphorylation. Interestingly, PAF-pretreated platelets still exhibited phosphorylation of proteins by thrombin. On the other hand, a lack of protein phosphorylation by PAF or thrombin was observed in platelets preexposed to thrombin and this demonstrated a heterologous desensitization. It is concluded that phosphorylation of proteins by PAF is a PAF receptor-coupled event and that this process is desensitized in platelets preexposed to PAF. The fact that both the activation of phosphoinositide-specific phospholipase C and the phosphorylation of proteins are desensitized in PAF-pretreated platelets suggests that a close "regulatory" intercommunication between these processes exists.  相似文献   
4.
Hepatocytes are highly polarized epithelia. Loss of hepatocyte polarity is associated with various liver diseases, including cholestasis. However, the molecular underpinnings of hepatocyte polarization remain poorly understood. Loss of β-catenin at adherens junctions is compensated by γ-catenin and dual loss of both catenins in double knockouts (DKOs) in mice liver leads to progressive intrahepatic cholestasis. However, the clinical relevance of this observation, and further phenotypic characterization of the phenotype, is important. Herein, simultaneous loss of β-catenin and γ-catenin was identified in a subset of liver samples from patients of progressive familial intrahepatic cholestasis and primary sclerosing cholangitis. Hepatocytes in DKO mice exhibited defects in apical-basolateral localization of polarity proteins, impaired bile canaliculi formation, and loss of microvilli. Loss of polarity in DKO livers manifested as epithelial-mesenchymal transition, increased hepatocyte proliferation, and suppression of hepatocyte differentiation, which was associated with up-regulation of transforming growth factor-β signaling and repression of hepatocyte nuclear factor 4α expression and activity. In conclusion, concomitant loss of the two catenins in the liver may play a pathogenic role in subsets of cholangiopathies. The findings also support a previously unknown role of β-catenin and γ-catenin in the maintenance of hepatocyte polarity. Improved understanding of the regulation of hepatocyte polarization processes by β-catenin and γ-catenin may potentially benefit development of new therapies for cholestasis.

A hallmark of epithelial cells is polarization, which is achieved by the orchestration of external cues, such as cellular contact, extracellular matrix, signal transduction, growth factors, and spatial organization.1 Hepatocytes in the liver show a unique polarity by forming several apical and basolateral poles within a cell.2 The apical poles of adjacent hepatocytes form a continuous network of bile canaliculi into which bile is secreted, whereas the basolateral membrane domain forms the sinusoidal pole, which secretes various components, such as proteins or drugs, into the blood circulation.3 Loss of hepatic polarity has been associated with several cholestatic and developmental disorders, including progressive familial intrahepatic cholestasis (PFIC) and primary sclerosing cholangitis (PSC).4,5 Although the molecular mechanisms governing hepatocyte polarity have been extensively studied in the in vitro systems, there is still a significant gap in our understanding of how polarity is established within the context of tissue during development or maintained during homeostasis.6,7 Similarly, the molecular pathways contributing to hepatic polarity are not entirely understood, and a better comprehension of hepatic polarity regulation is thus warranted.Previous studies have confirmed the role of hepatocellular junctions, such as tight and gap junctions, in the maintenance of hepatocyte polarity.8,9 Studies done in vitro and in vivo have shown that loss of junctional proteins, such as zonula occludens protein (ZO)-1, junctional adhesion molecule-A, and claudins, lead to impairment of polarity and distorted bile canaliculi formation.10, 11, 12, 13 In addition, proteins involved in tight junction assembly, such as liver kinase B1, are also involved in polarity maintenance.14 Among adherens junction proteins, various in vitro cell culture models have confirmed the role of E-cadherin in the regulation of hepatocyte polarity, possibly through its interaction with β-catenin.15,16 However, there is a lack of an in vivo model to study the role of adherens junction proteins in hepatocyte polarity and their misexpression contributing to various liver diseases.β-Catenin plays diverse functions in the liver during development, regeneration, zonation, and tumorigenesis.17, 18, 19 The relative contribution of β-catenin as part of the adherens junction is challenging to study because like in other tissues, γ-catenin compensates for the β-catenin loss in the liver.20,21 To address this redundancy, we previously reported a hepatocyte-specific β-catenin and γ-catenin double-knockout (DKO) mouse model was reported.22 Simultaneous deletion of β-catenin and γ-catenin in mice livers led to cholestasis, partially through the breach of cell-cell junctions. However, more comprehensive understanding of the molecular underpinnings of the phenotype is needed.In the current study, prior preclinical findings of dual β-catenin and γ-catenin loss were extended to a subset of PFIC and PSC patients. In vivo studies using the murine model with hepatocyte-specific dual loss of β-catenin and γ-catenin showed complete loss of hepatocyte polarity compared to the wild-type controls (CONs). Loss of polarity in DKO liver was accompanied by epithelial-mesenchymal transition (EMT), activation of transforming growth factor (TGF)-β signaling, and reduced expression of hepatocyte nuclear factor 4α (HNF4α). Our findings suggest that β-catenin and γ-catenin and in turn adherens junction integrity, are critical for the maintenance of hepatocyte polarity, and any perturbations in this process can contribute to the pathogenesis of cholestatic liver disease.  相似文献   
5.
The 44-amino-acid E5 oncoprotein of bovine papillomavirus type 1 transforms immortalized murine fibroblast cell lines. This highly hydrophobic protein forms homodimers, localizes to intracellular membrane compartments (including the Golgi apparatus), and forms a complex with the 16-kDa membrane-embedded constituent (16k) of the vacuolar proton-ATPase. To develop a system for the genetic and biochemical analysis of the E5/16k interaction, the E5 gene was cloned into a new vector which was designed for expression in the fission yeast Schizosaccharomyces pombe. The E5 protein synthesized in this system dimerized normally and bound to endogenous and overexpressed S. pombe 16k protein. Comparison of the S. pombe and mammalian 16k proteins showed strong conservation in carboxyl-terminal amino acids but greater variation in the amino-terminal sequences, suggesting that E5 was interacting with the 16k carboxyl domains. Finally, a new protein epitope tag is described which permitted for the first time the coprecipitation of E5 with antibodies directed against the 16k protein.  相似文献   
6.
Trefoil factor family 2 (TFF2) is a small peptide constitutively expressed in the gastric mucosa, where it plays a protective role in restitution of gastric mucosa. TFF2 has also been shown to be expressed in some gastric cancers, but its role in tumor metastasis and patient prognosis has not been examined. In this study, we examined TFF2 expression at both the mRNA and protein levels and correlated these results with the clinicopathologic characteristics and prognosis of gastric cancer patients. Among the 144 curatively resected samples, 43 (30%) were positive for TFF2. TFF2 expression was preferentially observed in the infiltrating tumor cells sparing the superficial cells. Significantly increased expression of TFF2 was noted in large tumors of the diffuse type. An increased prevalence of TFF2 expression was also found in tumors with advanced T and N stage and in patients with lymphatic and venous invasion. Accordingly, patients with TFF2-expressing tumors had a significantly worse disease-free survival, and in multivariate analysis, this finding remained significant as an independent prognostic factor. Taken together, our results suggest that TFF2 expression may play a role in gastric cancer invasion and as such could be a useful target for therapeutic intervention.  相似文献   
7.
The polymerization of styrene initiated by 2,2′-azoisobutyronitrile (AIBN) was studied in N,N-dimethylformamide (DMF) solution at 60°C in the presence of tetrakis(N,N-dimethylformamide)copper(II) perchlorate, and also in the presence of its monoazido copper(II) complex [Cu(DMF)3N3]+. The monoazido complex in DMF was prepared in situ by mixing solid sodium azide with tetrakis(N,N-dimethylformamide)copper(II) perchlorate in a mole ratio of 1:1. The nature of the complex was established by Job's method. The equilibrium constant K for the reaction [Cu(DMF)4]2+ + N ? [Cu(DMF)3N3]+ + DMF determined by the limiting logarithmic method was found to be 1,25 · 104l · mol?1. The presence of [Cu(DMF)4]2+ ions in the polymerization systems caused retardation, but [Cu(DMF)3N3]+ ions produced well defined induction periods. The rate constants at 60°C for the interaction of polystyryl radical towards [Cu(DMF)4]2+ and [Cu(DMF)3N3]+ ions were calculated to be 6,6 · 102 and 5,74 · 104 l · mol?1 · s?1, respectively.  相似文献   
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9.
Summary. A sandwich ELISA test using PPR specific monoclonal antibody (clone 4G6) to an epitope of nucleocapsid protein has been developed. The test uses polyclonal sera to capture the antigen from clinical samples (swabs and tissues). Captured antigens from clinical samples are detected using PPR specific monoclonal antibody. The test is specific to PPR as it failed to detect rinderpest vaccine virus (RBOK strain). Varieties of clinical samples originating from laboratory experiments (n=231) and from field (n=259) were employed to test the efficacy of sandwich-ELISA test. The test compared very well with an internationally accepted commercial Immune-capture ELISA kit, which uses biotinylated monoclonal antibody against the nucleocapsid protein. On a parallel testing using 490 clinical samples, 4G6 MAb based sandwich ELISA had an overall relative diagnostic specificity of 92.8% and diagnostic sensitivity of 88.9% compared to the commercial kit. The newly developed test is free from prozone phenomenon. PPR outbreaks from various parts of India have been confirmed using the test. Findings suggested that the newly developed ELISA is suitable for PPR diagnosis under field conditions.  相似文献   
10.
A rapid and highly sensitive real-time PCR detection and quantification method for infectious hypodermal and hematopoietic necrosis virus (IHHNV), a single-stranded DNA virus, and white spot virus (WSV), a double-stranded DNA (dsDNA) virus infecting penaeid shrimp (Penaeus sp.), was developed using the GeneAmp 5700 sequence detection system coupled with SYBR Green chemistry. The PCR mixture contains a fluorescence dye, SYBR Green, which upon binding to dsDNA exhibits fluorescence enhancement. The enhancement of fluorescence was proportional to the initial concentration of the template DNA. A linear relationship was observed between the amount of input plasmid DNA and cycle threshold (C(T)) values over a range of 1 to 10(5) copies of the viral genome. To control the variation in sampling and processing among samples, the shrimp beta-actin gene was amplified in parallel with the viral DNA. The C(T) values of IHHNV- and WSV-infected samples were used to determine absolute viral copy numbers from the standard C(T) curves of these viruses. For each virus and its beta-actin control, the specificity of amplification was monitored by using the dissociation curve of the amplified product. Using genomic DNA as a template, SYBR Green PCR was found to be 100- to 2000-fold more sensitive than conventional PCR, depending on the virus, for the samples tested. The results demonstrate that SYBR Green PCR can be used as a rapid and highly sensitive detection and quantification method for shrimp viruses and that it is amenable to high-throughout assay.  相似文献   
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