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1.
mBio ; : e0131823, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37938000

RESUMO

Hepatitis C virus (HCV) is the leading cause of death from liver disease. How HCV infection causes lasting liver damage and increases cancer risk remains unclear. Here, we identify bipotent liver stem cells as novel targets for HCV infection, and their erroneous differentiation as the potential cause of impaired liver regeneration and cancer development. We show 3D organoids generated from liver stem cells from actively HCV-infected individuals carry replicating virus and maintain low-grade infection over months. Organoids can be infected with a primary HCV isolate. Virus-inclusive single-cell RNA sequencing uncovered transcriptional reprogramming in HCV+ cells supporting hepatocytic differentiation, cancer stem cell development, and viral replication while stem cell proliferation and interferon signaling are disrupted. Our data add a new pathogenesis mechanism-infection of liver stem cells-to the biology of HCV infection that may explain progressive liver damage and enhanced cancer risk through an altered stem cell state.ImportanceThe hepatitis C virus (HCV) causes liver disease, affecting millions. Even though we have effective antivirals that cure HCV, they cannot stop terminal liver disease. We used an adult stem cell-derived liver organoid system to understand how HCV infection leads to the progression of terminal liver disease. Here, we show that HCV maintains low-grade infections in liver organoids for the first time. HCV infection in liver organoids leads to transcriptional reprogramming causing cancer cell development and altered immune response. Our finding shows how HCV infection in liver organoids mimics HCV infection and patient pathogenesis. These results reveal that HCV infection in liver organoids contributes to liver disease progression.

2.
Open Biol ; 12(3): 210320, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35232252

RESUMO

Hepatitis C virus (HCV) remains a global public health challenge with an estimated 71 million people chronically infected, with surges in new cases and no effective vaccine. New methods are needed to study the human immune response to HCV since in vivo animal models are limited and in vitro cancer cell models often show dysregulated immune and proliferative responses. Here, we developed a CD8+ T cell and adult stem cell liver organoid system using a microfluidic chip to coculture 3D human liver organoids embedded in extracellular matrix with HLA-matched primary human T cells in suspension. We then employed automated phase contrast and immunofluorescence imaging to monitor T cell invasion and morphological changes in the liver organoids. This microfluidic coculture system supports targeted killing of liver organoids when pulsed with a peptide specific for HCV non-structural protein 3 (NS3) (KLVALGINAV) in the presence of patient-derived CD8+ T cells specific for KLVALGINAV. This demonstrates the novel potential of the coculture system to molecularly study adaptive immune responses to HCV in an in vitro setting using primary human cells.


Assuntos
Linfócitos T CD8-Positivos , Hepatite C , Organoides , Linfócitos T CD8-Positivos/imunologia , Técnicas de Cocultura , Hepacivirus , Hepatite C/imunologia , Humanos , Microfluídica , Proteínas não Estruturais Virais/imunologia
3.
Obes Surg ; 31(10): 4289-4294, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34291361

RESUMO

INTRODUCTION/PURPOSE: The objective of this research was to characterize the impact of Roux-en-Y gastric bypass (RYGB) on the pharmacokinetic properties of the pro-drug lisdexamfetamine and its active metabolite, d-amphetamine. MATERIALS AND METHODS: A case-control design was used where patients who had undergone RYGB 9-24 months prior were matched on sex, age, and body mass index (BMI) to nonsurgical controls who had no history of weight loss surgery. Each participant received a single 50 mg dose of lisdexamfetamine, and plasma samples were collected over a 24-h period following dosing. Noncompartmental analyses were used to compare pharmacokinetic measures between groups. RESULTS: There were no significant differences between the RYGB (n = 10) and NSC groups (n = 10) on sex (70% female), age (40.9 ± 9.6 vs. 41.3 ± 8.9 years), BMI (30.3 ± 5.2 vs. 31 ± 5.9 kg/m2), or ethnicity (100% vs. 80% White). The pharmacokinetic parameters between the RYGB and NCS groups were found to be equivalent for lisdexamfetamine and d-amphetamine, including maximum plasma concentration (Cmax), time to maximum plasma concentration (Tmax), and area under the plasma concentration-time curve (AUC(0-∞)). CONCLUSION: These data suggest that there is no need to routinely adjust lisdexamfetamine dosing following RYGB. However, given the potential for inter-individual differences, patients who undergo RYGB should be clinically monitored and individualized dosing strategies should be considered for concerns surrounding efficacy or toxicity.


Assuntos
Derivação Gástrica , Obesidade Mórbida , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Humanos , Dimesilato de Lisdexanfetamina , Masculino , Obesidade Mórbida/cirurgia , Estudos Retrospectivos
4.
Int J Eat Disord ; 53(9): 1418-1427, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32583478

RESUMO

OBJECTIVE: Innovative treatments and outcome measures are needed for binge-eating disorder (BED). This randomized controlled trial compared Integrative Cognitive-Affective Therapy (ICAT-BED), an individual psychotherapy targeting momentary behavioral and emotional precipitants of binge eating, with an established cognitive-behavioral guided self-help (CBTgsh) treatment using standard and ecological momentary assessment (EMA) outcome measures. METHOD: A total of 112 participants were randomized to 17 weeks of treatment (21 sessions for ICAT-BED and 10 sessions for CBTgsh). Binge-eating frequency was assessed with the Eating Disorder Examination (EDE) as well as EMA using cell phone-based real-time, naturalistic assessment at end of treatment (EOT) and 6-month follow-up. Hypothesized maintenance mechanisms were assessed using self-report questionnaires. RESULTS: Binge-eating frequency as measured by the EDE and real-time assessment showed significant reductions at EOT and follow-up, with no significant differences between treatments. Hypothesized maintenance mechanisms, including emotion regulation, cognitive self-discrepancy, self-directed style, as well as measures of associated eating disorder psychopathology, depression, anxiety, impulsivity, and negative affect, showed similar improvement at EOT and follow-up with no differences between treatments. Abstinence rates at EOT (ICAT-BED: 57.1%; CBTgsh: 42.9%) and 6-month follow-up (ICAT-BED: 46.4%; CBTgsh: 42.9%) were not significantly different. Treatment retention was significantly higher for ICAT-BED (87.5%) than CBTgsh (71.4%). DISCUSSION: These findings suggest that ICAT-BED and CBTgsh were associated with similar improvements in binge eating, psychopathology, and putative maintenance mechanisms as measured by traditional self-report and momentary, naturalistic assessments and that these changes were generally sustained at 6-month follow-up.


Assuntos
Transtorno da Compulsão Alimentar/terapia , Terapia Cognitivo-Comportamental/métodos , Avaliação de Resultados em Cuidados de Saúde/métodos , Psicoterapia/métodos , Grupos de Autoajuda/normas , Adolescente , Adulto , Idoso , Transtorno da Compulsão Alimentar/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
6.
Obes Surg ; 28(11): 3544-3552, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30062468

RESUMO

BACKGROUND: Obstructive sleep apnea (OSA) is extremely common among bariatric surgical candidates. Identifying those at risk for moderate to severe OSA is challenging. Testing all bariatric surgical candidates with a level 1 polysomnographic study is expensive and resource intensive. The aim of this study is to evaluate three standardized screening questionnaires that are utilized to identify high-risk patients for OSA undergoing bariatric surgery. METHODS: A retrospective review of data collected prospectively was undertaken on bariatric surgical patients who have not had a preexisting diagnosis of OSA. Each patient was subjected to the STOP BANG and Berlin Questionnaires as well as the Epworth Sleepiness Scale (ESS), after which a level 1 polysomnogram was undertaken. Nonparametric receiver operating characteristic analyses were used to evaluate the relationship between questionnaire scores and OSA as determined by a formal sleep lab study. RESULTS: There were 266 patients subjected to a standard overnight polysomnogram and screening questionnaires. Area under the curve (AUC) values for analyses including the entire sample were significantly (p < .05) greater than chance (i.e., AUC = .50) for all questionnaire scores except the ESS for both severe OSA (AUC range = .584-.631) and moderate/severe OSA (AUC range = .589-.660), although the magnitude of the AUC values was quite modest. Sensitivity and specificity values from the current study are substantially lower than those previously reported in the literature. CONCLUSIONS: Neither the STOP BANG nor Berlin questionnaires appear to be effective tools for detecting moderate- or high-risk patients for OSA undergoing bariatric surgery.


Assuntos
Cirurgia Bariátrica/métodos , Obesidade Mórbida , Apneia Obstrutiva do Sono , Humanos , Obesidade Mórbida/complicações , Obesidade Mórbida/epidemiologia , Obesidade Mórbida/cirurgia , Polissonografia , Estudos Retrospectivos , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/epidemiologia , Inquéritos e Questionários
7.
Psychiatry Res ; 244: 294-9, 2016 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-27512918

RESUMO

Two of the primary components within Integrative Cognitive Affective Therapy (ICAT) are self-discrepancy and self-directed style. Self-discrepancy includes both actual:ideal (discrepancy between oneself and who one wishes they were) and actual:ought (discrepancy between oneself and who one believes they ought to be). Self-directed style in ICAT refers to a variety of behaviors emitted by a person toward the self including self-blaming and self-affirming. This study explored main effects and interactions between self-discrepancy and self-directed style in relation to global eating disorder (ED) psychopathology, depressive symptoms, and anxiety. Eighty treatment-seeking adults from the Midwest with BN or subthreshold BN completed interviews and self-report measures. Self-affirm and self-blame were associated with ED psychopathology, depressive symptoms, and anxiety. Actual:ideal discrepancy was related to anxiety and actual:ought discrepancy was related to anxiety and depressive symptoms. Interactions were found between self-affirm and actual:ought discrepancy as well as self-blame and actual:ought discrepancy for depressive symptoms. High actual:ought was related to increased depressive symptoms regardless of levels of self-affirm or self-blame. Effect sizes for models were medium-to-large with anxiety models demonstrating the largest effects. This study provides further evidence supporting the ICAT model and treatment, which targets self-discrepancies, self-directed styles, and related emotional states.


Assuntos
Ansiedade/psicologia , Bulimia Nervosa/psicologia , Depressão/psicologia , Adolescente , Adulto , Terapia Cognitivo-Comportamental , Emoções , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autoimagem , Adulto Jovem
8.
J Behav Addict ; 4(3): 195-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26551910

RESUMO

BACKGROUND: Previous research has identified exercise identity and social physique anxiety as two independent factors that are associated with exercise dependence. AIMS: The purpose of our study was to investigate the unique and interactive effect of these two known correlates of exercise dependence in a sample of 1,766 female runners. METHODS: Regression analyses tested the main effects of exercise identity and social physique anxiety on exercise dependence. An interaction term was calculated to examine the potential moderating effect of social physique anxiety on the exercise identity and exercise dependence relationship. RESULTS: Results indicate a main effect for exercise identity and social physique anxiety on exercise dependence; and the interaction of these factors explained exercise dependence scores beyond the independent effects. Thus, social physique anxiety acted as a moderator in the exercise identity and exercise dependence relationship. DISCUSSION: Our results indicate that individuals who strongly identify themselves as an exerciser and also endorse a high degree of social physique anxiety may be at risk for developing exercise dependence. CONCLUSIONS: Our study supports previous research which has examined factors that may contribute to the development of exercise dependence and also suggests a previously unknown moderating relationship for social physique anxiety on exercise dependence.


Assuntos
Ansiedade/psicologia , Imagem Corporal/psicologia , Exercício Físico/psicologia , Identificação Social , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Análise de Regressão , Corrida/psicologia , Inquéritos e Questionários
9.
Pharmacotherapy ; 35(9): 876-80, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26406775

RESUMO

STUDY OBJECTIVE: As data are limited for dosing warfarin in patients who have undergone bariatric surgery, our objective was to gather data on warfarin pharmacotherapy to aid in the prescribing practices and dosage adjustment of warfarin after Roux-en-Y gastric bypass (RYGB) surgery. DESIGN: Retrospective medical record review. SETTING: Anticoagulation clinic. PATIENTS: Twelve patients who underwent RYGB surgery between 2009 and 2011. MEASUREMENTS AND MAIN RESULTS: Data were collected on patient demographics, therapeutic indications for warfarin, weekly warfarin doses, and international normalized ratio (INR) values before and after RYGB surgery. To examine whether the relationship between the warfarin dose and therapeutic effect (i.e., INR) of warfarin changed from before to after surgery, we generated a ratio between each INR measurement and the weekly warfarin dose that immediately preceded it (warfarin dose/INR ratio). Mean weekly warfarin dose after RYGB surgery decreased significantly relative to presurgery dose (estimated marginal mean ± SE presurgery dose 37.08 ± 3.31 mg vs postsurgery dose 28.08 ± 3.27 mg; [F(205.63) = 13.23, p<0.001]), whereas INRs increased significantly after surgery from presurgery levels (estimated marginal mean ± SE presurgery INR 2.36 ± 0.15 vs postsurgery INR 2.94 ± 0.14; [F(213.76) = 6.55, p<0.05]). The ratio of warfarin dose/INR from presurgery (estimated marginal mean ± SE 17.64 ± 1.67) to postsurgery (estimated marginal mean ± SE 10.94 ± 1.64) was also significantly reduced [F(206.47) = 20.61, p<0.001], suggesting that a lower warfarin dose was required to produce the desired INR after surgery compared with before surgery. CONCLUSION: Warfarin dosages tended to decrease after RYGB surgery, in agreement with previously published literature. These findings suggest the need for increased INR monitoring and patient education for patients taking warfarin after RYGB surgery.


Assuntos
Anticoagulantes/administração & dosagem , Derivação Gástrica/métodos , Varfarina/administração & dosagem , Adulto , Anticoagulantes/farmacologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Coeficiente Internacional Normatizado , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Varfarina/farmacologia
10.
J Sport Exerc Psychol ; 35(5): 464-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24197714

RESUMO

The purpose of our study was to examine exercise dependence (EXD) in a large community-based sample of runners. The secondary purpose of this study was to examine differences in EXD symptoms between primary and secondary EXD. Our sample included 2660 runners recruited from a local road race (M age = 38.78 years, SD = 10.80; 66.39% women; 91.62% Caucasian) who completed all study measures online within 3 weeks of the race. In this study, EXD prevalence was lower than most previously reported rates (gamma = .248, p < .001) and individuals in the at-risk for EXD category participated in longer distance races, F(8,1) = 14.13, p = .01, partial eta squared = .05. Group differences were found for gender, F(1,1921) 8.08, p = .01, partial eta squared = .004, and primary or secondary group status, F(1,1921) 159.53, p = .01, partial eta squared = .077. Implications of primary and secondary EXD differences and future research are discussed.


Assuntos
Atletas/psicologia , Comportamento Obsessivo/epidemiologia , Comportamento Obsessivo/psicologia , Resistência Física/fisiologia , Corrida/psicologia , Adulto , Atletas/estatística & dados numéricos , Exercício Físico/fisiologia , Exercício Físico/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Feminino , Humanos , Masculino , North Dakota/epidemiologia , Corrida/estatística & dados numéricos , Distribuição por Sexo
11.
Obes Surg ; 23(12): 2013-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23912263

RESUMO

BACKGROUND: LSG has been increasingly performed. Long-term follow-up is necessary. METHODS: During the Fourth International Consensus Summit on LSG in New York Dec. 2012, an online questionnaire (SurveyMonkey®) was filled out by 130 surgeons experienced in LSG. The survey was submitted directly to the statisticians. RESULTS: The 130 surgeons performed 354.9 ± SD 453 LSGs/surgeon (median 175), for a total of 46,133 LSGs. The LSGs had been performed over 4.9 ± 2.7 year (range 1-10). Of the 46,133 LSGs, 0.2 ± 1.0 % (median 0, range 0-10 %) were converted to an open operation. LSG was intended as the sole operation in 93.1 ± 14.8 %; in 3.0 ± 6.3 %, a second stage became necessary. Of the 130 surgeons, 40 (32 %) use a 36F bougie, which was most common (range 32-50F). Staple-line is reinforced by 79 %; of these, 57 % use a buttress and 43 % over-sew. Mean %EWL at year 1 was 59.3 %; year 2, 59.0 %; year 3, 54.7 %; year 4, 52.3 %; year 5, 52.4 %; and year 6, 50.6 %. If a second-stage operation becomes necessary, preference was: RYGB 46 %, duodenal switch 24 %, re-sleeve 20 %, single-anastomosis duodenoileal bypass 3 %, sleeve plication 3 %, minigastric bypass 3 %, non-adjustable band 2 %, and side-to-side jejunoileal anastomosis 1 %. Complications were: high leak 1.1 %, hemorrhage 1.8 %, and stenosis at lower sleeve 0.9 %. Postoperative gastroesophageal reflux occurred in 7.9 ± 8.2 % but was variable (0-30 %). Mortality was 0.33 ± 1.6 %, which translates to ≈ 152 deaths. Eighty-nine percent order multivitamins (including vitamin D, calcium, and iron) and 72 % order B12. A PPI is ordered by 29 % for 1 month, 29 % for 3 months, and others for 1-12 months depending on the case. CONCLUSIONS: LSG was relatively safe. Further long-term surveillance is necessary.


Assuntos
Gastrectomia , Laparoscopia , Obesidade Mórbida/cirurgia , Feminino , Humanos , Tempo de Internação , Masculino , Obesidade Mórbida/epidemiologia , Guias de Prática Clínica como Assunto , Reoperação , Inquéritos e Questionários , Resultado do Tratamento , Redução de Peso
12.
Body Image ; 10(1): 70-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23092850

RESUMO

Previous research has connected exercise identity with obligatory exercise, yet to date no empirical studies have identified moderator variables of this association. The current study included participants of an athletic event (full marathon, n=582; half marathon, n=1,106; shorter distance, n=733) who completed questionnaires about exercise behaviors, obligatory exercise, and internalization of both the thin-ideal and athletic-ideal body shapes. General linear model analyses were conducted to examine the exercise identity-obligatory exercise relationship; moderator variables included gender, internalization of the thin-ideal body shape, and internalization of the athletic-ideal body shape. After controlling for the effects of body mass index, age, and distance group, the three-way interaction of exercise identity, gender, and internalization of the athletic-ideal body shape predicted obligatory exercise. Findings suggest that women who report high identification with exercise and high value on having an athletic physique may be vulnerable to obligatory exercise.


Assuntos
Transtornos Dismórficos Corporais/diagnóstico , Transtornos Dismórficos Corporais/psicologia , Imagem Corporal/psicologia , Exercício Físico/psicologia , Identificação Psicológica , Motivação , Corrida/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Tamanho Corporal , Comportamento Compulsivo/diagnóstico , Comportamento Compulsivo/psicologia , Feminino , Inquéritos Epidemiológicos , Humanos , Controle Interno-Externo , Masculino , Pessoa de Meia-Idade , Meio-Oeste dos Estados Unidos , Fatores Sexuais , Magreza/psicologia , Adulto Jovem
13.
Surg Obes Relat Dis ; 7(6): 749-59, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21945699

RESUMO

BACKGROUND: Laparoscopic sleeve gastrectomy (LSG) has been performed for morbid obesity in the past 10 years. LSG was originally intended as a first-stage procedure in high-risk patients but has become a stand-alone operation for many bariatric surgeons. Ongoing review is necessary regarding the durability of the weight loss, complications, and need for second-stage operations. METHODS: The first International Summit for LSG was held in October 2007, the second in March 2009, and this third in December 2010. There were presentations by experts, and, to provide a consensus, a questionnaire was completed by 88 attendees who had >1 year (mean 3.6 ± 1.5, range 1-8) of experience with LSG. RESULTS: The results of the questionnaire were based on 19,605 LSGs performed within 3.6 ± 1.5 years (228.8 ± 275.0 LSGs/surgeon). LSG had been intended as the sole operation in 86.4% of the cases; in these, a second-second stage became necessary in 2.2%. LSG was completed laparoscopically in 99.7% of the cases. The mean percentage of excess weight loss at 1, 2, 3, 4, and 5 years was 62.7%, 64.7%, 64.0%, 57.3%, and 60.0%, respectively. The bougie size was 28-60F (mean 36F, 70% blunt tip). Resection began 1.5-7.0 cm (mean 4.8) proximal to the pylorus. Of the surgeons, 67.1% reinforced the staple line, 57% with buttress material and 43% with oversewing. The respondents excised an estimated 92.9% ± 8.0% (median 95.0%) of fundus (i.e., a tiny portion is maintained lateral to the angle of His). A drain is left by 57.6%, usually closed suction. High leaks occurred in 1.3% of cases (range 0-10%); lower leaks occurred in .5%. Intraluminal bleeding occurred in 2.0% of cases. The mortality rate was .1% ± .3%. CONCLUSION: According to the questionnaire, presentations, and debates, the weight loss and improvement in diabetes appear to be better than with laparoscopic adjustable gastric banding and on par with Roux-en-Y gastric bypass. High leaks are infrequent but problematic.


Assuntos
Gastrectomia/métodos , Derivação Gástrica/métodos , Laparoscopia/métodos , Obesidade Mórbida/cirurgia , Redução de Peso/fisiologia , Procedimentos Cirúrgicos Ambulatórios , Consenso , Complicações do Diabetes/cirurgia , Gastrectomia/efeitos adversos , Derivação Gástrica/efeitos adversos , Refluxo Gastroesofágico/etiologia , Gastroscopia/métodos , Hérnia Hiatal/etiologia , Humanos , Laparoscopia/efeitos adversos , Tempo de Internação , Cidade de Nova Iorque , Recidiva , Reoperação , Deiscência da Ferida Operatória/etiologia , Inquéritos e Questionários , Resultado do Tratamento
14.
Behav Res Ther ; 49(10): 579-87, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21802657

RESUMO

Psychological trauma in childhood has been shown to increase a variety of psychological disturbances and psychiatric disorders. Although evidence-based treatments for children who have been traumatized exist, they are infrequently used by clinicians treating children. The present paper describes the creation of the Treatment Collaborative for Traumatized Youth (TCTY) which is a statewide partnership in North Dakota designed to disseminate efficacious treatments for traumatized children and monitor outcomes across a broad, rural, geographic expanse. The paper reviews the dissemination strategy developed by the TCTY, reports outcomes regarding both clinicians and child participants, and highlights problems identified in the project and solutions that were generated.


Assuntos
Maus-Tratos Infantis/psicologia , Medicina Baseada em Evidências , Disseminação de Informação/métodos , Serviços de Saúde Mental/normas , Transtornos de Estresse Pós-Traumáticos/terapia , Adolescente , Criança , Proteção da Criança/psicologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Transtornos Mentais/etiologia , Transtornos Mentais/psicologia , Transtornos Mentais/terapia , North Dakota , Avaliação de Resultados em Cuidados de Saúde , Projetos Piloto , Avaliação de Programas e Projetos de Saúde , Transtornos de Estresse Pós-Traumáticos/etiologia , Transtornos de Estresse Pós-Traumáticos/psicologia
16.
FEBS J ; 278(1): 69-77, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21078126

RESUMO

RING finger protein 13 (RNF13) is a ubiquitously expressed, highly regulated ubiquitin ligase anchored in endosome membranes. A RING domain located in the cytoplasmic half of this type 1 membrane protein mediates ubiquitination in vitro but physiological substrates have not yet been identified. The protein localized in endosomal membranes undergoes extensive proteolysis in a proteasome-dependent manner, but the mRNA level can be increased and the encoded protein stabilized under specific physiological conditions. The cytoplasmic half of RNF13 is released from the membrane by regulatory proteases and therefore has the potential to mediate ubiquitination at distant sites independent of the full-length protein. In response to protein kinase C activation, the full-length protein is stabilized and moves to recycling endosomes and to the inner nuclear membrane, which exposes the RING domain to the nucleoplasm. Thus RNF13 is a ubiquitin ligase that can potentially mediate ubiquitination in endosomes, on the plasma membrane, in the cytoplasm, in the nucleoplasm or on the inner nuclear membrane, with the site(s) regulated by signaling events that modulate protein targeting and proteolysis.


Assuntos
Endossomos/enzimologia , Processamento de Proteína Pós-Traducional , Ubiquitina-Proteína Ligases/metabolismo , Humanos , Modelos Biológicos , Transporte Proteico , Ubiquitina-Proteína Ligases/química
17.
Int J Eat Disord ; 43(5): 472-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20527049

RESUMO

OBJECTIVE: This study examined the frequency and characteristics of alli use among patients in eating disorder treatment facilities. METHOD: Patients from five treatment centers completed the Survey of Eating and Related Behaviors. Diagnoses were determined from survey responses. RESULTS: Of 417 survey respondents, 26 (6.2%) reported a history of alli use. Of those, 15 (57.7%) met criteria for an eating disorder, including one of 29 patients (3.4%) with anorexia nervosa binge-purge subtype, six of 66 patients (9.1%) with full or subthreshold bulimia nervosa, four of 49 (8.2%) with binge eating disorder, one of six (16.7%) with purging disorder, and three of 80 (3.8%) with an eating disorder not otherwise specified. DISCUSSION: The results of this survey suggest that patients with eating disorders use alli, albeit relatively uncommonly. Therefore, it is worthwhile for clinicians to inquire about alli use when evaluating or treating these patients in any clinical setting.


Assuntos
Comportamento Alimentar/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Lactonas/administração & dosagem , Fármacos Antiobesidade/administração & dosagem , Feminino , Inquéritos Epidemiológicos , Humanos , Orlistate
18.
Traffic ; 11(6): 756-66, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20230530

RESUMO

Ring finger protein 13 (RNF13) is an E3 ubiquitin ligase embedded in endosome membranes. The protein undergoes constitutive post-translational proteolysis, making its detection difficult unless cells are incubated with a proteasome inhibitor to allow biosynthetic forms to accumulate. When cells were treated with phorbol 12-myristate 13-acetate (PMA), RNF13 avoided proteolysis. A similar stabilization was seen on ionomycin treatment of cells. Drug treatment stabilized both the full-length protein and a membrane-embedded C-terminal fragment generated following ectodomain shedding. Immunofluorescence staining revealed that PMA treatment caused the protein to accumulate in recycling endosomes, where it colocalized with transferrin receptor, and on the inner nuclear membrane, where it colocalized with lamin B. Expression of dominant-negative Rab11 inhibited nuclear localization, suggesting RNF13 was targeted to the inner nuclear membrane through recycling endosomes. New protein synthesis was necessary for this targeting. Nuclear localization was confirmed by immunoelectron microscopy and by purification of the inner nuclear membrane. Stress-induced transport of an endosomal protein to the inner nuclear membrane is a novel mechanism for introduction of regulatory proteins to the DNA environment. RNF13, with its ubiquitin ligase-active RING domain, has the potential to turn over key nuclear proteins in response to signals received at the plasma membrane.


Assuntos
Núcleo Celular/metabolismo , Endossomos/enzimologia , Ubiquitina-Proteína Ligases/metabolismo , Animais , Células CHO , Membrana Celular/metabolismo , Cricetinae , Cricetulus , Humanos , Membranas Intracelulares/metabolismo , Microscopia Imunoeletrônica/métodos , Inibidores de Proteassoma , Estrutura Terciária de Proteína , Receptores da Transferrina/metabolismo , Acetato de Tetradecanoilforbol/química , Ubiquitina-Proteína Ligases/química
19.
Immunology ; 129(2): 186-96, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19824915

RESUMO

Natural killer (NK) cells bridge the interface between innate and adaptive immunity and are implicated in the control of herpes simplex virus 2 (HSV-2) infection. In subjects infected with human immunodeficiency virus 1 (HIV-1), the critical impact of the innate immune response on disease progression has recently come into focus. Higher numbers of NK cells are associated with lower HIV-1 plasma viraemia. Individuals with the compound genotype of killer cell immunoglobulin-like receptor (KIR) 3DS1 and human leucocyte antigen (HLA)-Bw4-80I, or who have alleles of KIR3DL1 that encode proteins highly expressed on the NK cell surface, have a significant delay in disease progression. We studied the effect of HSV-2 co-infection in HIV-1-infected subjects, and show that HSV-2 co-infection results in a pan-lymphocytosis, with elevated absolute numbers of CD4(+) and CD8(+) T cells, and NK cells. The NK cells in HSV-2 co-infected subjects functioned more efficiently, with an increase in degranulation after in vitro stimulation. The number of NK cells expressing the activating receptors NKp30 and NKp46, and expressing KIR3DL1 or KIR3DS1, was inversely correlated with HIV-1 plasma viral load in subjects mono-infected with HIV-1, but not in subjects co-infected with HSV-2. This suggests that HSV-2 infection mediates changes within the NK cell population that may affect immunity in HIV-1 infection.


Assuntos
Soropositividade para HIV/imunologia , HIV-1/imunologia , Herpes Simples/imunologia , Herpesvirus Humano 2/imunologia , Células Matadoras Naturais/metabolismo , Adulto , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Linfócitos T CD8-Positivos/virologia , Contagem de Células , Células Cultivadas , Citotoxicidade Imunológica , Progressão da Doença , Feminino , Soropositividade para HIV/complicações , Soropositividade para HIV/patologia , Soropositividade para HIV/fisiopatologia , HIV-1/patogenicidade , Antígenos HLA-B/genética , Antígenos HLA-B/metabolismo , Herpes Simples/complicações , Herpes Simples/patologia , Herpes Simples/fisiopatologia , Herpesvirus Humano 2/patogenicidade , Teste de Histocompatibilidade , Humanos , Imunidade Inata , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/patologia , Células Matadoras Naturais/virologia , Linfocitose , Masculino , Pessoa de Meia-Idade , Receptores KIR3DL1/genética , Receptores KIR3DL1/metabolismo , Receptores KIR3DS1/genética , Receptores KIR3DS1/metabolismo
20.
Phys Rev Lett ; 103(12): 127003, 2009 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-19792454

RESUMO

We measure changes in the penetration depth lambda of the T_{c} approximately 6 K superconductor LaFePO. In the process, scanning SQUID susceptometry is demonstrated as a technique for accurately measuring local temperature-dependent changes in lambda, ideal for studying early or difficult-to-grow materials. lambda is found to vary linearly with temperatures from 0.36 to approximately 2 K, with a slope of 143 +/- 15 A/K, suggesting line nodes in the superconducting order parameter. The linear dependence up to approximately T_{c}/3, similar to the cuprate superconductors, indicates well-developed nodes.

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