Protein content of precipitates present in pancreatic juice of alcoholic subjects and patients with chronic calcifying pancreatitis

Chronic calcifying pancreatitis is characterized by the formation of intraductal protein plugs or precipitates and calcified stones in ducts. Similar precipitates may be collected by endoscopic retrograde catheterization of the main pancreatic duct. They are present in the pancreatic juice of alcoholic subjects and patients with chronic calcifying pancreatitis. Protein analysis of these precipitates was performed to try to elucidate the mechanism of stone formation. Two protein fraction were separated by extraction of precipitates. One fraction was easily soluble in saline and contained a small amount of most of the proteins of pancreatic juice. The other fraction was soluble in citrate or ethylenediaminetetraacetate and contained a few proteins with close isoelectric points and identical molecular weight (13,500). These proteins showed immunological identity with the "stone protein" isolated from human pancreatic calculi. Our data demonstrate that the major citrate-soluble protein of precipitates in pancreatic juice is identical with "stone protein". They are strongly support the concept that this protein is the organic matrix of pancreatic stones. Different mechanisms are proposed to explain the phenomenon of protein precipitation that frequently occurs in alcoholic subjects and patients with chronic calcifying pancreatitis.     

Seroepidemiological studies of El Tor cholera in Bangladesh: association of serum antibody levels with protection

In rural Bangladesh, family contacts of patients with cholera were studied prospectively to examine whether protection against colonization and disease due to Vibrio cholerae O1 was associated with circulating antibodies to V. cholerae. Family contacts (1,071) of 370 patients with cholera were visited daily for 10 days, cultured for V. cholerae, and queried about diarrhea. Sera collected on days 1 and 21 were assayed for vibriocidal antibodies, IgG and IgA antibodies to cholera toxin, and IgG antibodies to lipopolysaccharide (LPS). Vibriocidal titers of greater than or equal to 20 present in 50% of contacts by 20 years of age were associated with protection against both colonization and disease. An elevated level of IgG antitoxin was not associated with protection against colonization or disease but was the most sensitive indicator of recent symptomatic cholera and of immune response to the oral immunogen B subunit. IgG antibody to LPS and IgA antitoxin were of little value in predicting colonization or disease.     

Characterization of the Zebrafish atxn1/axh Gene Family

In mammals, ataxin-1 (ATXN1) is a member of a family of proteins in which each member contains an AXH domain. Expansion of the polyglutamine tract in ATXN1 causes the neurodegenerative disease, spinocerebellar ataxia type 1 (SCA1) with prominent cerebellar pathology. Toward a further characterization of the genetic diversification of the ATXN1/AXH gene family, we identified and characterized members of this gene family in zebrafish, a lower vertebrate with a cerebellum. The zebrafish genome encodes two ATXN1 homologs, atxn1a and atxn1b, and one ATXN1L homolog, atxn1l. Key biochemical features of the human ATXN1 protein not seen in the invertebrate homologs (a nuclear localization sequence and a site of phosphorylation at serine 776) are conserved in the zebrafish homologs, and all three zebrafish Atxn1/Axh proteins behave similarly to their human counterparts in tissue-culture cells. Importantly, each of the three homologs is expressed in the zebrafish cerebellum, which in humans, is a prominent site of SCA1 pathogenesis. In addition, atxn1a and atxn1b are expressed in the developing zebrafish cerebellum. These data show that in zebrafish, a lower vertebrate, the complexity of the atxn1/axh gene family is more similar to higher vertebrates than invertebrates with a simple central nervous system and suggests a relationship between the diversification of the ATXN1/AXH gene family and the development of a complex central nervous system, including a cerebellum.     

Correction to: Role of complement and potential of complement inhibitors in myasthenia gravis and neuromyelitis optica spectrum disorders: a brief review

Journal of Neurology - The original version of this article unfortunately contained a mistake. Fifth sentence of the fourth paragraph in the section “Non-nAChR autoantibody targets in...     

Telomere fusions in early human breast carcinoma

Several lines of evidence suggest that defects in telomere maintenance play a significant role in the initiation of genomic instability during carcinogenesis. Although the general concept of defective telomere maintenance initiating genomic instability has been acknowledged, there remains a critical gap in the direct evidence of telomere dysfunction in human solid tumors. To address this topic, we devised a multiplex PCR-based assay, termed TAR (telomere-associated repeat) fusion PCR, to detect and analyze chromosome end-to-end associations (telomere fusions) within human breast tumor tissue. Using TAR fusion PCR, we found that human breast lesions, but not normal breast tissues from healthy volunteers, contained telomere fusions. Telomere fusions were detected at similar frequencies during early ductal carcinoma in situ and in the later invasive ductal carcinoma stage. Our results provide direct evidence that telomere fusions are present in human breast tumor tissue and suggest that telomere dysfunction may be an important component of the genomic instability observed in this cancer. Development of this robust method that allows identification of these genetic aberrations (telomere fusions) is anticipated to be a valuable tool for dissecting mechanisms of telomere dysfunction.     

Upregulation of GAD65 mRNA in the medulla of the rat model of metabolic syndrome

Although alterations in the function of the neurotransmitter system have been implicated in the pathology of Alzheimer's disease (AD), the mechanisms that underlie this pathological change are not well understood. Beta-site amyloid precursor protein cleaving enzyme 1 (BACE1) is a key protease in the generation of beta-amyloid, an important trigger protein in the pathogenesis of AD. The expression and activity of BACE1 are increased in the brains of sporadic AD patients, and a role for BACE1 in neurotransmission has been suggested recently. This study examines whether BACE1 plays a role in regulated exocytosis in PC12 cells. Treatment of PC12 cells with a beta-secretase inhibitor reduced stimulus-dependent secretion of neurotransmitters, suggesting a potential role of BACE1 in regulated exocytosis. Using transfected human growth hormone as a reporter for a regulated secretory pathway in PC12 cells, we found that the transient overexpression of BACE1 increased basal secretion in the absence of a stimulus and reduced stimulus-dependent secretion in intact PC12 cells. In digitonin-permeabilized PC12 cells, an overexpression of BACE1 enhanced the Ca2+-independent and ATP-independent component of the secretory pathway. Furthermore, expression of the glycosylation-deficient mutant of BACE1, BACE1N354Q, led to an elevation of basal secretions over that by BACE1 wild-type, suggesting a role of BACE1 glycosylation in basal secretion. These results demonstrate an unknown role for BACE1 in secretion, and suggest that elevated levels of BACE1 in AD brains may contribute to the altered neurotransmitter pathology of AD through stimulation of spontaneous basal secretion under resting conditions.     

Men’s perspectives on women’s empowerment and intimate partner violence in rural Bangladesh

Intimate partner violence (IPV) may increase as women in patriarchal societies become empowered, implicitly or explicitly challenging prevailing gender norms. Prior evidence suggests an inverse U-shaped relationship between women’s empowerment and IPV, in which violence against women first increases and then decreases as more egalitarian gender norms gradually gain acceptance. By means of focus-group discussions and in-depth interviews with men in 10 Bangladeshi villages, this study explored men’s evolving views of women, gender norms and the legitimacy of men’s perpetration of IPV in the context of a gender transition. It examines men’s often-contradictory narratives about women’s empowerment and concomitant changes in norms of masculinity, and identifies aspects of women’s empowerment that are most likely to provoke a male backlash. Findings suggest that men’s growing acceptance of egalitarian gender norms and their self-reported decreased engagement in IPV are driven largely by pragmatic self-interest: their desire to improve their economic status and fear of negative consequences of IPV.