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S Stone

Publications and source records attributed to S Stone.

At least 91 records · Page 5Linked to original sources
PubMed2000

Prenatal alcohol exposure increases TNFalpha-induced cytotoxicity in primary astrocytes.

We examined the effect of prenatal alcohol exposure (PAE) on tumor necrosis factor-alpha-(TNFalpha) induced cell death in primary astrocyte cultures. Flow cytometry revealed that PAE increased the sensitivity of astrocytes to the cytotoxic effects of TNFalpha when compared to astrocytes prepared from pair-fed and chow-fed controls. In a number of cell types, TNFalpha regulates cell growth or death, in part, by the hydrolysis of sphingomyelin to ceramide and sphingosine-1-phosphate (SPP). Using a 3-(4. 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxic assay we found that PAE increased the sensitivity of astrocytes to the cytotoxic effects of TNFalpha, sphingomyelinase (SMase), and C(2)- and C(6)-ceramide. The increasing cellular concentrations of SPP, a sphingolipid metabolic that induces cell growth, protected the cells from TNFalpha-induced cell death. N, N-dimethylsphingosine (DMS), which inhibits SPP production, and N-oleoylethanolamine, which inhibits acid ceramidases, increased TNFalpha-induced cytotoxicity in astrocytes prepared from PAE rats. These studies suggest that PAE shifts the balance of sphingolipid metabolism in favor of a pathway that increases the susceptibility of astrocytes to the cytotoxic effect of TNFalpha.

Animals↗
PubMed2000

Sentinel node biopsy for staging of aggressive digital papillary adenocarcinoma.

BACKGROUND: Aggressive digital papillary adenocarcinoma is a rare malignancy with a propensity for metastases and recurrence. The role of lymph node staging in this tumor is poorly defined. We describe the use of sentinel lymph node mapping and biopsy in staging this tumor. OBJECTIVE: To describe and discuss the use of lymphatic mapping in staging aggressive digital papillary adenocarcinoma. METHODS: Sentinel lymph node mapping and biopsy was performed after excision of an aggressive digital papillary adenocarcinoma of the toe. RESULTS: Metastatic tumor cells were absent in sentinel lymph nodes by hematoxylin and eosin staining and immunocytochemistry analysis. CONCLUSION: We describe the first reported case of staging lymph nodes in a patient with aggressive digital papillary adenocarcinoma utilizing sentinel lymph node mapping and biopsy.

Adenocarcinoma, Papillary↗
PubMed2000

Antibiotic prescribing for patients with colds, upper respiratory tract infections, and bronchitis: A national study of hospital-based emergency departments.

STUDY OBJECTIVE: Antibiotics are often used to treat viral upper respiratory tract infections, even though they are usually ineffective. However, frequent inappropriate antibiotic use contributes to the emergence of drug-resistant bacterial pathogens. This study used a national database to evaluate antibiotic use in treating upper respiratory tract infections in emergency departments. METHODS: Data were obtained from the 1996 National Hospital Ambulatory Medical Care Survey. Antibiotic prescribing rates were examined for colds, upper respiratory tract infections, and acute bronchitis. Patients with comorbid conditions or secondary diagnoses, such as chronic obstructive pulmonary disease, pneumonia, sinusitis, and HIV, were excluded. Bivariate and multivariate analyses were used to assess predictors of antibiotic use. RESULTS: Overall, there were an estimated 2.7 million ED visits for colds, upper respiratory tract infections, and bronchitis by children and adults in 1996. Antibiotics were prescribed for 24.2% (95% CI 18.9, 29.5) of patients with common colds and upper respiratory tract infections and for 42.2% (95% CI 35.2, 49.2) of patients with bronchitis. There were no significant associations between antibiotic use and patient race, sex, Hispanic ethnicity, geographic location, or source of payment. Antibiotics were prescribed less often by interns or residents than by staff or other physicians (odds ratio 0.43; 95% CI 0.19, 0.98), and patients younger than 18 years were less likely to receive antibiotics than adults (odds ratio 0.32; 95% CI 0.20, 0.52). Smokers were 4.3 (95% CI 2.2, 8.3) times more likely to receive antibiotics than nonsmokers. CONCLUSION: Antibiotics are commonly prescribed for ED patients with upper respiratory tract infections even though they are usually ineffective in otherwise healthy adults. Efforts should be made to reduce inappropriate antibiotic use for the sake of containing costs, preventing side effects, and limiting the spread of antibiotic resistance.

Adolescent↗
PubMed2000

A normal livebirth after intracytoplasmic sperm injection for globozoospermia without assisted oocyte activation: case report.

The successful outcome of intracytoplasmic sperm injection (ICSI) with round-headed spermatozoa (globozoospermia) is reported. A couple with infertility secondary to globozoospermia received ICSI treatment. Fertilization, cleavage and pregnancy outcomes were recorded. This couple experienced 40, 10 and 42% fertilization rates after ICSI in their first, second and third cycles respectively. Pregnancy did not occur in the first or second cycle but was successfully achieved after the third ICSI cycle. It is concluded that current ICSI procedures may overcome the infertility associated with globozoospermia and result in normal healthy livebirth without assisted oocyte activation.

Adult↗
PubMed2000

Ethanol increases the neurotoxic effect of tumor necrosis factor-alpha in cultured rat astrocytes.

BACKGROUND: The central nervous system is particularly sensitive to the cytotoxic effect of ethanol. In vivo and in vitro studies indicate that ethanol decreases cell proliferation in a number of cells types, including neurons and glial cells in the central nervous system. The cellular mechanisms involved in ethanol-induced cell toxicity, however, are unclear. In this study, we examined the effect of ethanol on tumor necrosis factor-alpha (TNFalpha)-induced cell death in a homogeneous population of cultured rat astrocytes. METHODS: Flow cytometric and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenytetrazolium bromide (MTT) dye reduction analyses were performed on cultured rat astrocytes to determine the effect of alcohol on TNFalpha-induced cell death. RESULTS: Flow cytometric analysis revealed that, in quiescent astrocytes, high concentrations of ethanol were required to increase DNA fragmentation and decrease cell viability. Preexposure of astrocytes to low concentrations of ethanol (10 to 50 mM), however, increased the sensitivity of astrocytes to TNFalpha with low TNFalpha concentrations (25 to 50 ng/ml) resulting in increased DNA fragmentation. Furthermore, MTT dye reduction analysis revealed that exposure of astrocytes to 5 mM ethanol was sufficient to increase the susceptibility of astrocytes to the cytotoxic effect of ethanol. In a number of cell types, TNFalpha receptor binding results in the activation of specific signal transduction cascades, including the hydrolysis of sphingomyelin to ceramide. We show that preexposure of astrocytes to a low concentration of ethanol increased the sensitivity of astrocytes to sphingomyelinase, and C2-ceramide resulting in increased DNA fragmentation and decreased cell viability. More importantly, astrocytes prepared from rats exposed to ethanol prenatally showed increased susceptibility to TNFalpha-induced cell death. CONCLUSIONS: These studies suggest that ethanol increases the susceptibility of astrocytes to TNFalpha-induced cell death by shifting the balance of sphingolipid metabolism in favor of a pathway that increases the susceptibility of astrocytes to the cytotoxic effect of TNFalpha.

Animals↗
PubMed2000

Ethanol inhibits prolactin- and tumor necrosis factor-alpha-, but not gamma interferon-induced expression of intercellular adhesion molecule-1 in human astrocytoma cells.

In humans, alcohol consumption has multiple effects on the immune system. Despite an increase in our understanding of the effects of alcohol on the immune system, little is known about the effect of alcohol on the neuroimmune response. In the central nervous system (CNS), astrocytes and microglial function as immune effector cells. In response to infection of injury, astrocytes increase in number and size, express several proinflammatory cytokines, MHC class I and II antigens, and several adhesion molecules, including intercellular adhesion molecule-1 (ICAM-1). Interactions between ICAM-1 and its counter-receptors play an important role in the regulation of neuroimmune response. In this study, cultured human astrocytoma cells were used to examine the effect of ethanol on ICAM-1 expression. Western blot analyses show that quiescent astrocytes express, at least, four immunoreactive ICAM-1 proteins with apparent molecular weights 55, 67, 82, and 90 kDa. Incubation of human astrocytoma cells with tumor necrosis factor-alpha (TNF-alpha) or prolactin (PRL) resulted in marked increases in all four immunoreactive ICAM-1 proteins. In the presence of ethanol, however, PRL- and TNF-alpha-induced increases in all four immunoreactive ICAM-1 proteins were markedly inhibited. ICAM-1 is a cell surface transmembrane glycoprotein. Using a cell surface specific ICAM-1 adhesion assay we found that in human astrocytoma cells TNF-alpha, interferongamma (IFN-gamma) and PRL increased cell surface ICAM-1 expression. Consistent with our Western blot analyses, ethanol significantly inhibited TNF-alpha- and PRL-induced cell surface ICAM-1 expression. By contrast, IFN-gamma-induced ICAM-1 expression was not inhibited by exposure of the cells to ethanol. Expression of ICAM-1 is regulated predominantly at the transcriptional level. In the present report, we show that TNF-alpha increased ICAM-1 mRNA levels in human astrocytoma cells and that ethanol markedly blocked TNF-alpha-induced increases in ICAM-1 mRNA levels. Further, we found that PRL-induced ICAM-1 expression was, at least in part, due to a PRL-induced increase in TNF-alpha syntheses and secretion. Our results clearly indicate that ethanol has a pronounced effect on ICAM-1 expression in human astrocytoma cells, thus suggesting that ETOH exposure may impair the immune response in the CNS by blocking leukocytes adhesion and migration into the CNS in response to injury or infection.

Animals↗
PubMed2000

A nursing association's leadership in primary health care: policy, projects, and partnerships in the 1990s.

This paper documents the work of one provincial nursing association, the Registered Nurses Association of British Columbia (RNABC), to promote primary health care (PHC) as the foundation of the health-care system. In 1990 the RNABC embarked on a comprehensive policy program to influence change from a nursing perspective. A wide array of strategies was used over a 10-year period to help make PHC a reality in British Columbia's health-care system. Successful strategies used during this period included: writing and distributing policy papers, conducting and evaluating demonstration projects, and developing partnerships with other groups. Some of the projects and their outcomes are highlighted, followed by a critical reflection on lessons learned through the various initiatives. Although remarkable achievements were made from the RNABC's policy work during the 1990s, the advancement of PHC requires further collaborative efforts using multiple strategies.

British Columbia↗
PubMed1999

Risk factors for injury to women from domestic violence.

BACKGROUND: Domestic violence is the most common cause of nonfatal injury to women in the United States. To identify risk factors for such injuries, we examined the socioeconomic and behavioral characteristics of women who were victims of domestic violence and the men who injured them. METHODS: We conducted a case-control study at eight large, university-affiliated emergency departments. The 256 intentionally injured women had acute injuries resulting from a physical assault by a male partner. The 659 controls were women treated for other conditions in the emergency department. Information was collected with a standardized questionnaire; no information was obtained directly from the male partners. RESULTS: The 256 intentionally injured women had a total of 434 contusions and abrasions, 89 lacerations, and 41 fractures and dislocations. In a multivariate analysis, the characteristics of the partners that were most closely associated with an increased risk of inflicting injury as a result of domestic violence were alcohol abuse (adjusted relative risk, 3.6; 95 percent confidence interval, 2.2 to 5.9); drug use (adjusted relative risk, 3.5; 95 percent confidence interval, 2.0 to 6.4); intermittent employment (adjusted relative risk, 3.1; 95 percent confidence interval, 1.1 to 8.8); recent unemployment (adjusted relative risk, 2.7; 95 percent confidence interval, 1.2 to 6.5); having less than a high-school-graduate's education (adjusted relative risk, 2.5; 95 percent confidence interval, 1.4 to 4.4); and being a former husband, estranged husband, or former boyfriend (adjusted relative risk, 3.5; 95 percent confidence interval, 1.5 to 8.3). CONCLUSIONS: Women at greatest risk for injury from domestic violence include those with male partners who abuse alcohol or use drugs, are unemployed or intermittently employed, have less than a high-school-graduate's education, and are former husbands, estranged husbands, or former boyfriends of the women.

Acute Disease↗
PubMed1999

A novel BTB/POZ transcriptional repressor protein interacts with the Fanconi anemia group C protein and PLZF.

Fanconi anemia (FA) is an autosomal recessive cancer susceptibility syndrome. The phenotype includes developmental defects, bone marrow failure, and cell cycle abnormalities. At least eight complementation groups (A-H) exist, and although three of the corresponding complementation group genes have been cloned, they lack recognizable motifs, and their functions are unknown. We have isolated a binding partner for the Fanconi anemia group C protein (FANCC) by yeast two-hybrid screening. We show that the novel gene, FAZF, encodes a 486 amino acid protein containing a conserved amino terminal BTB/POZ protein interaction domain and three C-terminal Krüppel-like zinc fingers. FAZF is homologous to the promyelocytic leukemia zinc finger (PLZF) protein, which has been shown to act as a transcriptional repressor by recruitment of nuclear corepressors (N-CoR, Sin3, and HDAC1 complex). Consistent with a role in FA, BTB/POZ-containing proteins have been implicated in oncogenesis, limb morphogenesis, hematopoiesis, and proliferation. We show that FAZF is a transcriptional repressor that is able to bind to the same DNA target sequences as PLZF. Our data suggest that the FAZF/FANCC interaction maps to a region of FANCC deleted in FA patients with a severe disease phenotype. We also show that FAZF and wild-type FANCC can colocalize in nuclear foci, whereas a patient-derived mutant FANCC that is compromised for nuclear localization cannot. These results suggest that the function of FANCC may be linked to a transcriptional repression pathway involved in chromatin remodeling.

Amino Acid Sequence↗
PubMed1999

Induction of transcription factor interferon regulatory factor-1 by interferon-gamma (IFN gamma) and tumor necrosis factor-alpha (TNF alpha) in FRTL-5 cells.

While it is well known that interferon-gamma (IFN gamma) and tumor necrosis factor-alpha (TNF alpha) play a role in the regulation of thyroid growth and differentiated functions, the cellular and molecular mechanisms involved in mediating the effects of IFN gamma and TNF alpha on thyroid function are unknown. In the present study, we used FRTL-5 rat thyroid cells to examine the effects of IFN gamma and TNF alpha on gene expression of transcription factor interferon regulatory factor-1 (IRF-1), which is involved in mediating the effects of these cytokines in a number of cell types. Northern blot analysis of FRTL-5 mRNA showed a single IRF-1 mRNA at 2.2 Kb. In quiescent FRTL-5 cells, IRF-1 mRNA levels were low but detectable by Northern analysis. Incubation of FRTL-5 cells with IFN gamma or TNF alpha resulted in a dose- and time-dependent increase in IRF-1 mRNA levels. We have shown that TNF-alpha and IFN-gamma act synergistically to block the TSH-induced increase in type I 5'-deiodinase(5'D-I) activity and 5'D-I gene expression in FRTL-5 rat thyroid cells. Incubation of FRTL-5 cells with IFN gamma and TNF alpha in combination, however, did not synergistically increase IRF-1 mRNA levels. Electrophoretic mobility shift assay (EMSA) revealed that IFN gamma induced the formation of a single complex to a IFN gamma activation site (GAS) probe in a dose dependent manner. Several lines of evidence suggest that TNF alpha activates transcription factor nuclear factor-kappa B (NF kappa B) through activation of protein kinase C (PKC) or the hydrolysis of sphingomyelin to ceramide in a number of cell types. Here we demonstrate that hydrolysis of sphingomyelin to ceramide by sphingomyelinase (SMase), but not activation of PKC by 12-O-tetradecanoylphorbol 13-acetate (TPA), was involved in the activation of NF kappa B in FRTL-5 cells. Similarly, hydrolysis of sphingomyelin to ceramide, but not activation of PKC, resulted in an increased in IRF-1 mRNA levels in FRTL-5 cells. The present data demonstrate that IFN gamma and TNF alpha increase IRF-1 mRNA levels in FRTL-5 cells through activation of GAS and NF kappa B binding proteins, respectively. Thus, our results suggest that upregulation of IRF-1 may play a role in mediating the effects of IFN gamma and TNF alpha on thyroid function. Our results also suggest that the induction of IRF-1 mRNA by IFN gamma and TNF alpha is not the cellular mechanism involved in the synergistic effect of these cytokines on thyroid function.

Animals↗
PubMed1999

Ethanol inhibits prolactin-induced activation of the JAK/STAT pathway in cultured astrocytes.

Alcohol consumption has multiple effects in the central nervous system (CNS). Whereas, alcohol is an immunosuppressive drug the effect of alcohol on the neuroimmune system, remains unclear. In cultured astrocytes, prolactin (PRL) induces mitogenesis and the expression of inflammatory cytokines, including tumor necrosis factor-alpha (TNF alpha). We have recently shown that whereas ethanol does not inhibit PRL receptor binding, it markedly inhibits PRL-induced mitogenesis and TNF alpha secretion in cultured astrocytes. It is clear that PRL activates the tyrosine phosphorylation of several proteins, including members of a novel family of protein tyrosine kinases, the Janus Kinases (JAKs). The aims of this study were to characterize PRL-induced activation of the JAK/STAT (signal transducers and activators of transcription) pathway, and to determine if ethanol affects JAK/STAT activation in cultured astrocytes. We found that PRL specifically increases the tyrosine phosphorylation of JAK2, but not JAK1, JAK3, or Tyk2, and the subsequent phosphorylation of STAT1 alpha, STAT5a, and STAT5b. Preincubation of astrocytes with ethanol markedly inhibited phosphorylation of JAK2, STAT1 alpha, STAT5a, and STAT5b. In PRL-stimulated astrocytes, ethanol inhibited binding of nuclear proteins to oligonucleotides corresponding to the gamma-interferon activated sequence (GAS). Further, ethanol blocked PRL-induced increases in interferon regulatory factor-1 (IRF-1) mRNA, a PRL/cytokine inducible transcription factor involved in the regulation of a number of cytokine inducible genes. The inhibition of tyrosine phosphorylation by ethanol was not a general effect, however, as we found that ethanol increased basal and NGF-induced tyrosine phosphorylation of extracellular signal-activated protein kinase-1 (ERK-1). These data indicate that ethanol inhibits PRL-induced tyrosine phosphorylation of the JAK/STAT pathway resulting in decreased nuclear GAS DNA binding and inhibition of the PRL inducible gene, IRF-1. Thus, suggesting that ethanol-induced inhibition of JAK2 phosphorylation may be one mechanism though which ethanol could after the brain's response to injury or infection.

Animals↗
PubMed1999

Effects of iodine repletion on thyroid morphology in iodine and/or selenium deficient rat term fetuses, pups and mothers.

It has been suggested that selenium deficiency aggravates the iodine-induced thyroid inflammation and necrosis in iodine-deficient Wistar rats and possibly in man. Studies were carried out to determine whether large amounts of iodine given to iodine-deficient pregnant Sprague-Dawley rats with or without selenium deficiency would induce inflammation and necrosis in their term fetal thyroids. Iodine deficiency was induced in the dams by a low iodine diet or perchlorate in the drinking water and iodine excess was achieved by iodinated drinking water during pregnancy or daily subcutaneous injections of iodine from days 20 to 22 of pregnancy, 1 day after perchlorate was discontinued. Studies were also carried out in 30-day-old pups whose nursing mothers were iodine-deficient (perchlorate) with or without selenium deficiency from conception onward. The administration of iodine restored the morphologic changes in the thyroid induced by iodine deficiency, irrespective of selenium status, toward normal without inflammatory changes or necrosis. Possible explanations for these unexpected findings are discussed.

Animals↗
PubMed1999

The oral administration of human thyroglobulin does not affect the incidence of lymphocytic thyroiditis in the biobreeding Worcester rat.

Oral tolerization with the appropriate antigen(s) to ameliorate autoimmune diseases in humans and in experimentally induced animal models, including experimentally autoimmune thyroiditis in mice, has been reported to be efficacious. Spontaneous and iodine induced (0.05% iodine in the drinking water) lymphocytic thyroiditis (LT) occurs in the diabetes mellitus (DM)-prone BioBreeding/Worcester (BB/Wor) rat. The present study was carried out to determine whether the oral administration of human thyroglobulin (hTg) would decrease the incidence of spontaneous and iodine-induced LT in the BB/Wor rat. Low iodine content hTg or bovine serum albumin (BSA) were given orally every 2 days for six doses beginning at age 50 days to BB/W rats, half of whom also received iodine in their drinking water. No effect or orally administered hTg was observed on thyroid weight, the incidence of LT or DM, or on serum thyroglobin antibodies (TgAb), thyrotropin (TSH), thyroxine (T4), and triiodothyronine (T3) concentrations when rats were killed at 100 days of age. In a second experiment, the oral administration of iodine rich hTg or BSA every 2 days for six doses beginning at 30 days of age to iodine-treated BB/Wor rats again did not affect the high incidence of LT or DM or serum TgAb, TSH, T4, and T3 concentrations. The present study suggests that oral tolerization with hTg does not affect spontaneous or iodine-induced lymphocytic thyroiditis or serum thyroglobulin antibodies in the BB/Wor rat.

Animals↗
PubMed1998

Eisenmenger syndrome. Factors relating to deterioration and death.

AIMS: To assess the natural history, risk factors for death and deterioration of patients with Eisenmenger Syndrome. METHODS: The clinical course of 188 patients from three different cardiac centres specialized in adult congenital heart defects, followed for a median period of 31 years, was retrospectively analysed. According to the diagnosis, 64 males and 124 females, mean age at last follow-up 33.02+/-12.8 years, were divided into two groups: simple (128) and complex (60) congenital heart disease. Events analysed were: time variation of Ability Index, pulmonary and cerebral complications, non-cardiac surgery, urate metabolism and renal function, arrhythmias, pregnancy and contraception, medical therapy and transplantation, death from all causes and sudden death. RESULTS: Eighty-four percent of the overall population showed a satisfactory Ability Index (1 and 2) at the first attendance (median age 25 years). Patients with complex heart disease and Eisenmenger reaction had earlier clinical deterioration (18.6+/-11.3 vs 26.7+/-12.2) and shorter survival (25.8+/-7.9 vs 32.5+/-14.6 years). Thirty-eight (20.2%) patients had at least one episode of haemoptysis between 20 and 40 years of age but it did not modify overall survival; 25 (13.2%) had pulmonary thromboembolism at a mean age of 35.2+/-13.4 years. Fifteen (7.9%) had a stroke and 7 (3.7%) a cerebral abscess at a mean age of 31.4+/-15.7 and 24.1+/-4.9 years, respectively. Cerebral complications influenced the quality of life but did not modify survival. Patients who had venesection showed a 2.04 times greater hazard ratio for haemoptysis. Venesection did not reduce cerebral complications and in 20% caused anaemia and iron deficiency. Other non-cardiac surgery with general anaesthesia carried risks (23.5% of deaths). Significant maternal mortality (27%) in relation to pregnancy occurred with constant deterioration in physical status, high incidence of spontaneous abortions (35.8%) and cardiac abnormalities in offspring (20%). Sixty-one patients died during follow-up, mainly by sudden death (29.5%), heart failure (22.9%) and from haemoptysis (11.4%). Eight patients had heart and lung transplantation and five died 1 week to 4 years after transplant. Deterioration in Ability Index (worsening symptoms), age, complex defects, blood creatinine level, right ventricular dysfunction and non-cardiac surgery were variables which affected the prognosis adversely with uni- and multivariate analysis. CONCLUSIONS: patients with Eisenmenger syndrome can survive to the seventh decade with informed medical care and protection from special risks

Adult↗
PubMed1998

Small ventricular septal defects in adults.

AIMS: To establish the frequency of complications in adults with small ventricular septal defects, which have not undergone surgery. METHODS AND RESULTS: One hundred and eighty-eight adults aged 17-72 (mean, 29.2) years with a small ventricular septal defect were studied. They were referred to a national cardiac centre (National Heart Hospital) and specialized grown-up congenital heart unit. One hundred and thirty-eight were examined in 1994-95. Fifty patients (26.6%) had additional cardiovascular lesions, most commonly a bicuspid aortic valve and/or coarctation. Spontaneous closure occurred in 19 (10%) between the age of 17 and 45 (mean, 27) years. Twenty-one (11.2%) had infective endocarditis. Aortic regurgitation developed in 37 (19.7%) patients; it was severe in nine. Atrial arrhythmias (supraventricular tachycardia or atrial fibrillation) occurred in 12 patients. In four patients, atrial fibrillation produced severe right-sided congestion with a left ventricular to right atrial shunt and haemodynamic features suggesting 'restrictive cardiomyopathy'. Four patients had ventricular arrhythmia. Disproportionate left ventricular enlargement on echocardiography and/or chest radiography was present in 26 (13.8%) without lesions to account for it. CONCLUSIONS: Eighty nine patients (47%) aged 17-44 (mean, 26.8) years had no complications through many years, while spontaneous closure occurred in 19 (10%) during adulthood. Forty-six (25%) had serious complications: infective endocarditis (11%), progressive aortic regurgitation (5%), age-related symptomatic arrhythmias (8.5%) and atrial fibrillation the commonest. Accepting that there may be a referral bias for those with complications, the course of a small ventricular septal defect is not necessarily benign during adult life.

Adolescent↗
PubMed1998

A high copy suppressor screen reveals genetic interactions between BET3 and a new gene. Evidence for a novel complex in ER-to-Golgi transport.

The BET3 gene in the yeast Saccharomyces cerevisiae encodes a 22-kD hydrophilic protein that is required for vesicular transport between the ER and Golgi complex. To gain insight into the role of Bet3p, we screened for genes that suppress the growth defect of the temperature-sensitive bet3 mutant at 34 degrees. This high copy suppressor screen resulted in the isolation of a new gene, called BET5. BET5 encodes an essential 18-kD hydrophilic protein that in high copy allows growth of the bet3-1 mutant, but not other ER accumulating mutants. This strong and specific suppression is consistent with the fact that Bet3p and Bet5p are members of the same complex. Using PCR mutagenesis, we generated a temperature-sensitive mutation in BET5 (bet5-1) that blocks the transport of carboxypeptidase Y to the vacuole and prevents secretion of the yeast pheromone alpha-factor at 37 degrees. The precursor forms of these proteins that accumulate in this mutant are indicative of a block in membrane traffic between the ER and Golgi apparatus. High copy suppressors of the bet5-1 mutant include several genes whose products are required for ER-to-Golgi transport (BET1, SEC22, USO1 and DSS4) and the maintenance of the Golgi (ANP1). These findings support the hypothesis that Bet5p acts in conjunction with Bet3p to mediate a late stage in ER-to-Golgi transport. The identification of mammalian homologues of Bet3p and Bet5p implies that the Bet3p/Bet5p complex is highly conserved in evolution.

Amino Acid Sequence↗