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1.
Gynecol Oncol ; 181: 170-178, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38215513

RESUMO

Germline and somatic genetic testing have become critical components of care for people with ovarian cancer. The identification of germline and somatic pathogenic variants as well as homologous recombination deficiency can contribute to the prediction of treatment response, prognostic outcome, and suitability for targeted agents (e.g. poly (ADP-ribose) polymerase (PARP) inhibitors). Furthermore, identifying germline pathogenic variants can prompt cascade genetic testing for at-risk relatives. Despite the clinical benefits and consensus recommendations from several organizations calling for universal genetic testing in ovarian cancer, only about one third of patients complete germline or somatic genetic testing. The members of the Society of Gynecologic Oncology (SGO) Clinical Practice Committee have composed this statement to provide an overview of germline and somatic genetic testing for patients with epithelial ovarian cancer, focusing on available testing modalities and options for care delivery.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Humanos , Feminino , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/terapia , Carcinoma Epitelial do Ovário/terapia , Carcinoma Epitelial do Ovário/tratamento farmacológico , Antineoplásicos/uso terapêutico , Mutação em Linhagem Germinativa , Testes Genéticos , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/uso terapêutico , Células Germinativas/patologia , Proteína BRCA1/genética , Proteína BRCA2/genética
2.
Phys Rev Lett ; 125(5): 055701, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32794848

RESUMO

We present a detailed investigation of the wave-vector dependence of collective atomic motion in Au_{49}Cu_{26.9}Si_{16.3}Ag_{5.5}Pd_{2.3} and Pd_{42.5}Cu_{27}Ni_{9.5}P_{21} supercooled liquids close to the glass transition temperature. Using x-ray photon correlation spectroscopy in a previously uncovered spatial range of only a few interatomic distances, we show that the microscopic structural relaxation process mimics the structure and presents a marked slowing down at the main average interparticle distance. This behavior is accompanied by dramatic changes in the shape of the intermediate scattering functions, which suggest the presence of large dynamical heterogeneities at length scales corresponding to a few particle diameters. A ballisticlike mechanism of particle motion seems to govern the structural relaxation of the two systems in the highly viscous phase, likely associated with hopping of caged particles in agreement with theoretical studies.

3.
Pneumologie ; 74(12): 813-841, 2020 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-33291162

RESUMO

Long-term oxygen therapy is of great importance both for reducing mortality and for improving performance in patients with chronic lung diseases. The prerequisites for Long-term oxygen therapy are adequate diagnostics and clearly defined indication. A causal distinction into chronic hypoxaemic and hypercapnic respiratory failure is reasonable, from which the differential indication for non-invasive ventilation results.The revised guideline covers the diagnostics and indication of chronic lung and heart diseases, the role of oxygen in terminal illness and gives a detailed description of available oxygen devices. The guideline is intended to help avoid undersupply, oversupply and false prescriptions. Furthermore, the chapter "Postacute Oxygen Therapy" discusses the procedure, relevant in everyday life, but not yet clearly defined, for prescribing oxygen therapy for the home at the end of an inpatient stay. Another important point, the correct prescription of mobile oxygen systems, is also presented in the guideline. This document is a revised version of the guideline for longterm oxygen therapy and replaces the version of 2008.


Assuntos
Pneumopatias , Ventilação não Invasiva , Oxigenoterapia/normas , Guias de Prática Clínica como Assunto , Doença Pulmonar Obstrutiva Crônica/terapia , Insuficiência Respiratória , Sociedades Médicas/normas , Alemanha , Humanos , Oxigenoterapia/métodos , Insuficiência Respiratória/diagnóstico , Insuficiência Respiratória/terapia , Fatores de Tempo
4.
J Eur Acad Dermatol Venereol ; 31(1): 163-168, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27323701

RESUMO

BACKGROUND: Rosacea is a chronic facial disease that may lead to feelings of stigmatization, which can negatively impact psychological and social well-being. OBJECTIVE: The aim of this study was to evaluate different aspects of rosacea that could contribute to feelings of stigmatization. METHODS: An online survey of a representative sample of the adult population in the UK, France, Germany and US was conducted to identify patients with rosacea based on presence of three or more clinical features. RESULTS: Among the patients who completed the survey (n = 807), mean age at first sign/symptom of rosacea was 31.3 ± 14.5 years; mean duration of disease was 102 ± 119 months. One-third of patients reported feelings of stigmatization (FS; n = 275). Male patients were more likely to experience FS (49% vs. 37.2% in non-FS population; P = 0.0037). Those with FS were more likely to avoid social situations (54.2% vs. 2.0%, P < 1.00E-10 ) and had a higher rate of depression (36.7% vs. 21.1%, P < 1.00E-10 ). CONCLUSIONS: Stigmatization is important in the daily lives of those with rosacea and should be taken into consideration in the management of these patients.


Assuntos
Rosácea/psicologia , Estereotipagem , Humanos , Rosácea/fisiopatologia
5.
Am J Physiol Gastrointest Liver Physiol ; 309(3): G135-45, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26089336

RESUMO

Loss of significant intestinal length from congenital anomaly or disease may lead to short bowel syndrome (SBS); intestinal failure may be partially offset by a gain in epithelial surface area, termed adaptation. Current in vivo models of SBS are costly and technically challenging. Operative times and survival rates have slowed extension to transgenic models. We created a new reproducible in vivo model of SBS in zebrafish, a tractable vertebrate model, to facilitate investigation of the mechanisms of intestinal adaptation. Proximal intestinal diversion at segment 1 (S1, equivalent to jejunum) was performed in adult male zebrafish. SBS fish emptied distal intestinal contents via stoma as in the human disease. After 2 wk, S1 was dilated compared with controls and villus ridges had increased complexity, contributing to greater villus epithelial perimeter. The number of intervillus pockets, the intestinal stem cell zone of the zebrafish increased and contained a higher number of bromodeoxyuridine (BrdU)-labeled cells after 2 wk of SBS. Egf receptor and a subset of its ligands, also drivers of adaptation, were upregulated in SBS fish. Igf has been reported as a driver of intestinal adaptation in other animal models, and SBS fish exposed to a pharmacological inhibitor of the Igf receptor failed to demonstrate signs of intestinal adaptation, such as increased inner epithelial perimeter and BrdU incorporation. We describe a technically feasible model of human SBS in the zebrafish, a faster and less expensive tool to investigate intestinal stem cell plasticity as well as the mechanisms that drive intestinal adaptation.


Assuntos
Adaptação Biológica/fisiologia , Intestinos , Síndrome do Intestino Curto/metabolismo , Animais , Antimetabólitos/farmacologia , Bromodesoxiuridina/farmacologia , Proliferação de Células , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Modelos Animais de Doenças , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Mucosa Intestinal/patologia , Intestinos/patologia , Intestinos/fisiopatologia , Intestinos/cirurgia , Masculino , Células-Tronco/fisiologia , Redução de Peso , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
6.
Lung ; 193(1): 63-70, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25503750

RESUMO

PURPOSE: Acute exacerbations (AE) in patients with COPD are associated with a decline in lung function, increased risk of hospitalization, and mortality. In this cross-sectional study we tested whether the level of objectively measured daily physical activity and exercise capacity are associated with the number of COPD exacerbations. METHODS: In 210 patients with COPD (67 % men; mean (SD) age: 63 (8) years) enrolled in The Obstructive Pulmonary Disease Outcomes Cohort of Switzerland (TOPDOCS) physical activity (PA) (steps per day, physical activity level, (PAL)), exercise capacity (6-min walking distance, (6MWD)), comorbidities, lung function, and medication were assessed. Differences between COPD patients with frequent (≥2 year) and infrequent (0-1 year) exacerbations were assessed. Univariate and multivariate analyses were performed to investigate whether the level of objectively measured daily physical activity and exercise capacity are associated with the number of COPD exacerbations. RESULTS: Patients with frequent AE had a significantly lower FEV1 and 6MWD compared to patients with infrequent AE. In univariate analysis, the number of exacerbations was inversely associated with FEV1, 6MWD, BMI, and smoking status while there was a positive association with RV/TLC and combined inhaled medication. However, there was no significant association with PAL and steps per day. In multivariate analysis, FEV1 and the use of combined inhaled medication were independently associated with the number of AE, after correction for covariates. CONCLUSIONS: The findings of this study imply that FEV1, independent of inhaled medication, is significantly associated with COPD exacerbations. Neither physical activity nor exercise capacity was independently associated with COPD exacerbations.


Assuntos
Tolerância ao Exercício , Pulmão/fisiopatologia , Atividade Motora , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Idoso , Distribuição de Qui-Quadrado , Comorbidade , Estudos Transversais , Progressão da Doença , Teste de Esforço , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Fatores de Risco , Índice de Gravidade de Doença , Suíça/epidemiologia , Fatores de Tempo , Capacidade Pulmonar Total
7.
Anal Bioanal Chem ; 406(14): 3297-304, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24068171

RESUMO

The use of electrospun nanofibers as functional material in paper-based lateral flow assays (LFAs) was studied. Specific chemical features of the nanofibers were achieved by doping the base polymer, poly(lactic acid) (PLA), with poly(ethylene glycol) (PEG) and polystyrene8K-block-poly(ethylene-ran-butylene)25K-block-polyisoprene10K-Brij76 (K3-Brij76) (KB). The LFAs were assembled such that the sample flowed through the nanofiber mat via capillary action. Initial investigations focused on the sustainable spinning and assembly of different polymer structures to allow the LFA format. Here, it was found that the base polymer poly(vinyl alcohol) (PVA), which was shown to function well in microfluidic biosensors, did not work in the LFA format. In contrast, PLA-based nanofibers enabled easy assembly. Three relevant features were chosen to study nanofiber-based functionalities in the LFA format: adsorption of antibodies, quantification of results, and nonspecific binding. In particular, streptavidin-conjugated sulforhodamine B (SRB)-encapsulating liposomes were captured by anti-streptavidin antibodies adsorbed on the nanofibers. Varying the functional polymer concentration within the PLA base enabled the creation of distinct capture zones. Also, a sandwich assay for the detection of Escherichia coli O157:H7 was developed using anti-E. coli antibodies as capture and reporter species with horseradish peroxidase for signal generation. A dose-response curve for E. coli with a detection limit of 1.9 × 10(4) cells was achieved. Finally, functional polymers were used to demonstrate that nonspecific binding could be eliminated using antifouling block copolymers. The enhancement of paper-based devices using functionalized nanofibers provides the opportunity to develop a broad spectrum of sensitive and specific bioassays with significant advantages over their traditional counterparts.


Assuntos
Técnicas Biossensoriais , Eletroquímica/métodos , Nanofibras , Papel , Adsorção , Anticorpos/química , Escherichia coli/metabolismo , Escherichia coli O157/química , Peroxidase do Rábano Silvestre/química , Imunoensaio , Lipossomos/química , Nanofibras/química , Polietilenoglicóis/química , Polímeros/química , Poliestirenos/química , Álcool de Polivinil/química , Ligação Proteica , Rodaminas/química , Estreptavidina/química
8.
J Chem Phys ; 141(4): 044304, 2014 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-25084907

RESUMO

We study the relaxation dynamics of photoexcited Fe-II complexes dissolved in water and identify the relaxation pathway which the molecular complex follows in presence of a hydration shell of bound water at the interface between the complex and the solvent. Starting from a low-spin state, the photoexcited complex can reach the high-spin state via a cascade of different possible transitions involving electronic as well as vibrational relaxation processes. By numerically exact path integral calculations for the relaxational dynamics of a continuous solvent model, we find that the vibrational life times of the intermittent states are of the order of a few ps. Since the electronic rearrangement in the complex occurs on the time scale of about 100 fs, we find that the complex first rearranges itself in a high-spin and highly excited vibrational state, before it relaxes its energy to the solvent via vibrational relaxation transitions. By this, the relaxation pathway can be clearly identified. We find that the life time of the vibrational states increases with the size of the complex (within a spherical model), but decreases with the thickness of the hydration shell, indicating that the hydration shell acts as an additional source of fluctuations.

9.
Hernia ; 28(4): 1161-1167, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38625434

RESUMO

PURPOSE: Risk of total extraperitoneal hernia repair (TEP) in patients with previous lower abdominal surgery (PLAS) is still debated. The present study was designed to assess the rate of conversion in TEP for inguinal hernia stratified by type of PLAS. METHODS: Variables on patients undergoing TEP inguinal hernia repair at our center were prospectively collected between July 2012 and May 2018. Patients with PLAS were compared to patients without PLAS. Furthermore, the most frequent subtypes of PLAS were defined and TEP conversion rate was stratified according to type of PLAS. RESULTS: A total of 1589 patients with TEP inguinal hernia repair were identified including 152 (9.6%) patients with PLAS. Operative time was increased in patients with PLAS (70 vs. 60 min, p < 0.001). Conversion from TEP to transabdominal preperitoneal patch plasty (TAPP) or Lichtenstein open inguinal hernia repair was eight-times more frequent after PLAS (8% vs. 1%, p < 0.001). Considering type of PLAS, open appendectomy was most frequently encountered, followed by multiple PLAS and surgery to the bladder and prostate (53%, 11% and 10%). After stratification for type of PLAS, conversions were most frequently found after previous surgery to the bladder or prostate and after multiple PLAS (conversion rate of 20% and 24%, p < 0.001). In contrast, conversion rate after open appendectomy was not increased. CONCLUSION: PLAS to the bladder and prostate is associated with TEP conversion. Selected patients might profit from a different operative approach for inguinal hernia repair.


Assuntos
Hérnia Inguinal , Herniorrafia , Humanos , Hérnia Inguinal/cirurgia , Masculino , Herniorrafia/métodos , Feminino , Pessoa de Meia-Idade , Idoso , Conversão para Cirurgia Aberta/estatística & dados numéricos , Telas Cirúrgicas , Estudos Prospectivos , Duração da Cirurgia , Adulto
10.
J Chem Phys ; 139(13): 134503, 2013 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-24116571

RESUMO

The relatively small dielectric Debye-like process of the monohydroxy alcohol 4-methyl-3-heptanol (4M3H) was found to depend slightly on the intramolecular conformation. Proton and deuteron nuclear magnetic resonance demonstrate that the hydroxyl dynamics and the overall molecular dynamics take place on similar time scales in contrast to the situation for the structural isomer 2-ethyl-1-hexanol (2E1H) [S. Schildmann et al., J. Chem. Phys. 135, 174511 (2011)]. This indicates a very weak decoupling of Debye-like and structural relaxation which was further probed using volume expansivity experiments. Shear viscosity as well as diffusometry measurements were performed and the data were analyzed in terms of the Debye-Stokes-Einstein equations. In mixtures of 4M3H with 2E1H the Debye-like process becomes much stronger and for 2E1H mole fraction of more than 25% the behavior of this alcohol is rapidly approached. This finding is interpreted to indicate that the ring-like supramolecular structures in 4M3H become energetically unfavorable when adding 2E1H, an alcohol that tends to form chain-like molecular aggregates. The concentration dependence of the Kirkwood factor in these mixtures displays a high degree of similarity with experimental results on monohydroxy alcohols in which the pressure or the location of the OH group within the molecular structure is varied.

11.
Respiration ; 85(2): 160-74, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23406723

RESUMO

The new Swiss Chronic Obstructive Pulmonary Disease (COPD) Guidelines are based on a previous version, which was published 10 years ago. The Swiss Respiratory Society felt the need to update the previous document due to new knowledge and novel therapeutic developments about this prevalent and important disease. The recommendations and statements are based on the available literature, on other national guidelines and, in particular, on the GOLD (Global Initiative for Chronic Obstructive Lung Disease) report. Our aim is to advise pulmonary physicians, general practitioners and other health care workers on the early detection and diagnosis, prevention, best symptomatic control, and avoidance of COPD as well as its complications and deterioration.


Assuntos
Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/terapia , Agonistas de Receptores Adrenérgicos beta 2/uso terapêutico , Antibacterianos/uso terapêutico , Broncodilatadores/uso terapêutico , Antagonistas Colinérgicos/uso terapêutico , Pressão Positiva Contínua nas Vias Aéreas , Exercício Físico , Expectorantes/uso terapêutico , Glucocorticoides/uso terapêutico , Humanos , Vacinas contra Influenza , Oximetria , Oxigenoterapia , Educação de Pacientes como Assunto , Inibidores de Fosfodiesterase/uso terapêutico , Vacinas Pneumocócicas , Pneumonectomia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Radiografia Torácica , Testes de Função Respiratória , Terapia Respiratória , Fatores de Risco , Autocuidado , Apoio Social , Inquéritos e Questionários , Tomografia Computadorizada por Raios X , Aumento de Peso , alfa 1-Antitripsina/uso terapêutico
12.
Eur J Gynaecol Oncol ; 34(5): 453-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24475582

RESUMO

PURPOSE OF INVESTIGATION: This study evaluates the association of clinical and pathologic characteristics of patients with uterine serous carcinoma (USC) with disease recurrence. MATERIALS AND METHODS: Surgically-staged patients with USC at a single institution were identified and clinical and pathologic variables were compared. RESULTS: Of the 51 patients included in this analysis, 75% percent received adjuvant chemotherapy, 51% received radiation therapy, and 47% received both. After a median follow-up of 33 months, 42% of patients had disease recurrence. On multivariable analysis, positive pelvic lymph nodes were associated with a shorter interval between surgery and recurrence: 13.6 months progression-free survival (PFS) with positive vs 17.2 months with negative lymph nodes (p = 0.05). Patients with early-stage disease who did not receive any adjuvant treatments had a significantly greater risk of disease recurrence (44.4% vs 7.70%, p = 0.043). CONCLUSION: In this population of surgically-staged patients with USC, pelvic lymph node metastases were predictive of a shorter PFS.


Assuntos
Cistadenocarcinoma Seroso/patologia , Neoplasias Uterinas/patologia , Idoso , Quimioterapia Adjuvante , Cistadenocarcinoma Seroso/mortalidade , Cistadenocarcinoma Seroso/terapia , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Estudos Retrospectivos , Neoplasias Uterinas/mortalidade , Neoplasias Uterinas/terapia
13.
Gynecol Oncol ; 125(1): 48-53, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22101154

RESUMO

OBJECTIVE: Lymphatic ascites is an unusual complication in patients with cancer. In the gynecologic oncology patient population, the most common etiology is operative lymph node dissection. The purpose of this study was to explore the incidence, presenting symptoms, methods of diagnosis and treatment modalities utilized for lymphatic ascites in patients undergoing lymph node dissection for gynecologic cancers. METHODS: This observational study retrospectively reviewed the charts of patients who underwent lymphadenectomy as part of the surgical management for a gynecologic cancer. Patients that developed postoperative lymphatic ascites between January 2000 and December 2010 were included for analysis. Data extracted from the medical records included tumor pathology, number of harvested lymph nodes, postoperative course, method of diagnosis and treatment. RESULTS: From a total of 300 surgical staging procedures, 12 patients with lymphatic ascites were identified (4%). The most common reported symptom was leakage of clear fluid per vagina (7, 58%), followed by abdominal distension (4, 33%). The median interval from surgery to development of symptoms was 12.5 days (range 0-22 days). 5 patients had complete resolution of symptoms with dietary modifications alone while 7 patients required paracentesis. The median time from surgery to resolution of symptoms was 44 days (range 9-99). CONCLUSION: Lymphatic ascites is an under recognized and infrequently reported postoperative complication. Although it usually resolves spontaneously or with conservative management without sequelae, this condition can significantly prolong postoperative recovery and cause patient discomfort. To our knowledge this is the largest group of patients undergoing gynecologic surgical staging procedures to be reviewed for the occurrence of lymphatic ascites.


Assuntos
Ascite/etiologia , Neoplasias dos Genitais Femininos/cirurgia , Excisão de Linfonodo , Linfonodos/patologia , Complicações Pós-Operatórias , Adulto , Idoso , Aorta Abdominal , Ascite/diagnóstico , Ascite/epidemiologia , Ascite/terapia , Feminino , Neoplasias dos Genitais Femininos/complicações , Neoplasias dos Genitais Femininos/patologia , Humanos , Incidência , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Paracentese , Pelve , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/terapia , Estudos Retrospectivos
14.
Eur Respir J ; 37(3): 492-500, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20530037

RESUMO

We investigated determinants of change in bronchial reactivity in the Swiss Cohort Study on Air Pollution and Lung Diseases in Adults (SAPALDIA), a population-based cohort with wide age range (29-72 yrs at follow-up). The role of sex, age, atopic status, smoking and body mass index (BMI) on percentage change in bronchial reactivity slope from the baseline value was analysed in 3,005 participants with methacholine tests in 1991 and 2002, and complete covariate data. Slope was defined as percentage decline in forced expiratory volume in 1 s from its maximal value per micromole of methacholine. Bronchial hyperreactivity prevalence fell from 14.3 to 12.5% during follow-up. Baseline age was nonlinearly associated with change in reactivity slope: participants aged <50 yrs experienced a decline and those above an increase during follow-up. Atopy was not associated with change, but accentuated the age pattern (p-value for interaction = 0.038). Smoking significantly increased slope by 21.2%, as did weight gain (2.7% increase per BMI unit). Compared with persistent smokers, those who ceased smoking before baseline or during follow-up experienced a significant decrease in slope (-27.7 and -23.9%, respectively). Differing, but not statistically different, age relationships and effect sizes for smoking and BMI between sexes were found. Mean bronchial reactivity increases after 50 yrs of age, possibly due to airway remodelling or ventilation-perfusion disturbances related to cumulative lifetime exposures.


Assuntos
Pneumopatias/patologia , Hipersensibilidade Respiratória/patologia , Adulto , Idoso , Testes de Provocação Brônquica/métodos , Estudos de Coortes , Feminino , Humanos , Hipersensibilidade , Masculino , Cloreto de Metacolina , Pessoa de Meia-Idade , Prevalência , Fumar , Espirometria/métodos , Inquéritos e Questionários , Suíça
15.
Appl Ergon ; 97: 103546, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34399370

RESUMO

This study investigates the effects of a dynamic seat pan design on sitting biomechanics, perceived pain and seat movement compared to a control. Thirty male participants were recruited for two experimental sessions consisting of a 2-h sitting exposure (standardized typing task). Spine angles, back muscle activity, perceived pain and calf circumference were measured pre and post exposure. Sitting in the dynamic condition resulted in lower pain ratings (p = 0.031), decreased calf circumference (p < 0.001), lower average seat pressure (p < 0.001), and greater seat contact area (p = 0.003) compared to the control. Spine angles and low back EMG for all 6 muscles showed no significant differences between chair conditions. These results suggest this dynamic seat pan design is effective at decreasing several negative components associated with sitting for the occupant. Future work should examine the longer-term effects of dynamic office chair features in the field setting with a more generalizable population.


Assuntos
Dor Lombar , Postura , Fenômenos Biomecânicos , Ergonomia , Humanos , Masculino , Percepção da Dor , Coluna Vertebral
16.
Eur Respir J ; 36(6): 1259-69, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20413537

RESUMO

The aim of the present study was to measure age-specific prevalence of airflow obstruction in Switzerland in smokers and never-smokers using pulmonary function tests and respiratory symptoms from 6,126 subjects participating in the Swiss Cohort Study on Air Pollution and Lung Diseases in Adults. The lower limit of normal of the forced expiratory volume in 1 s/forced vital capacity ratio was used to define airflow obstruction. Severity of airflow obstruction was graded according to the recommendations of the Global Initiative for Chronic Obstructive Lung Disease. Prevalence of airflow obstruction ranged from 2.5% in subjects aged 30-39 yrs to 8.0% in those aged ≥ 70 yrs. In multivariate analysis, age (OR 2.8, ≥ 70 yrs versus 30-39 yrs), smoking (OR 1.8) and asthma (OR 6.7) were associated with airflow obstruction. Never-smokers constituted 29.3% of subjects with airflow obstruction. Never-smokers with airflow obstruction were younger, more likely to be male and reported asthma more frequently than obstructive smokers. Obstructive smokers and never-smokers had similar level of symptoms and quality of life impairment. The prevalence of airflow obstruction in Switzerland is similar to other developed countries. Never-smokers account for a third of the prevalence, which is higher proportion than elsewhere. Airflow obstruction in never-smokers deserves attention because of its frequency and its similar health impact to that in smokers.


Assuntos
Obstrução das Vias Respiratórias/epidemiologia , Fumar/epidemiologia , Adulto , Fatores Etários , Idoso , Obstrução das Vias Respiratórias/fisiopatologia , Asma/epidemiologia , Asma/fisiopatologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Qualidade de Vida , Testes de Função Respiratória , Fatores de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Fumar/fisiopatologia , Suíça/epidemiologia
17.
Nature ; 430(7001): 761-4, 2004 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-15306804

RESUMO

Although often regarded as a network-former in conventional silicate glasses, Al(2)O(3) alone cannot be obtained as a bulk glass. Until now, glasses comprising continuously linked [AlO(x)] polyhedra have been prepared in only a few systems under very fast cooling conditions, which limits their dimensions to a few millimetres. Yet it is desirable to prepare bulk, or monolithic, alumina-rich glasses, with the prospect of superior mechanical, chemical and optical properties. Here we report a novel process for preparing very-high-alumina glasses and nanoscale glass-ceramics. Fully dense bulk articles in net shape are obtained through viscous sintering of glass microbeads. Additional heat treatment of the consolidated glasses leads to fully crystallized transparent glass-converted nanoceramics with a hardness similar to that of alumina. This method avoids the impracticably high applied pressures (more than 1 GPa) that have been required in most cases to prepare nanocrystalline ceramics by sintering, owing to the concurrent nature of densification and grain growth under pressureless conditions. The reported techniques can be extended to form glasses and nanoceramics in other oxide systems that do not include a conventional glass-forming component.

18.
Am J Hum Biol ; 22(2): 206-15, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19701887

RESUMO

The Barker model of the in utero origins of diminished muscle mass in those born small invokes the adaptive "sparing" of brain tissue development at the expense of muscle. Though compelling, to date this model has not been directly tested. This article develops an allometric framework for testing the principal prediction of the Barker model-that among those born small muscle mass is sacrificed to spare brain growth-then evaluates this hypothesis using data from the third National Health and Nutrition Examination Survey (NHANES III). The results indicate clear support for a negative relationship between the allometric development of the two tissues; however, a further consideration of conserved mammalian fetal circulatory patterns suggests the possibility that system-constrained patterns of developmental damage and "bet-hedging" responses in affected tissues may provide a more adequate explanation of the results. Far from signaling the end of studies of adaptive developmental programming, this perspective may open a promising new avenue of inquiry within the fields of human biology and the developmental origins of health and disease.


Assuntos
Encéfalo/crescimento & desenvolvimento , Recém-Nascido de Baixo Peso/crescimento & desenvolvimento , Músculo Esquelético/crescimento & desenvolvimento , Negro ou Afro-Americano , Encéfalo/embriologia , Criança , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Americanos Mexicanos , Modelos Neurológicos , Músculo Esquelético/embriologia , Estado Nutricional , Tamanho do Órgão , Circulação Placentária , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Fenômenos Fisiológicos da Nutrição Pré-Natal , População Branca
19.
J Cell Biol ; 154(3): 499-509, 2001 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-11489914

RESUMO

Cajal bodies (CBs) are nuclear structures involved in RNA metabolism that accumulate high concentrations of small nuclear ribonucleoproteins (snRNPs). Notably, CBs preferentially associate with specific genomic loci in interphase human cells, including several snRNA and histone gene clusters. To uncover functional elements involved in the interaction of genes and CBs, we analyzed the expression and subcellular localization of stably transfected artificial arrays of U2 snRNA genes. Although promoter substitution arrays colocalized with CBs, constructs containing intragenic deletions did not. Additional experiments identified factors within CBs that are important for association with the native U2 genes. Inhibition of nuclear export or targeted degradation of U2 snRNPs caused a marked decrease in the levels of U2 snRNA in CBs and strongly disrupted the interaction with U2 genes. Together, the results illustrate a specific requirement for both the snRNA transcripts as well as the presence of snRNPs (or snRNP proteins) within CBs. Our data thus provide significant insight into the mechanism of CB interaction with snRNA loci, strengthening the putative role for this nuclear suborganelle in snRNP biogenesis.


Assuntos
Corpos Enovelados/genética , Corpos Enovelados/metabolismo , RNA Nuclear Pequeno/genética , RNA Nuclear Pequeno/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Sequência de Bases , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Deleção de Genes , Células HeLa , Humanos , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Conformação de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , RNA Nuclear Pequeno/química , Proteínas de Ligação a RNA , Proteínas do Complexo SMN , Transcrição Gênica/fisiologia
20.
J Cell Biol ; 129(5): 1181-93, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7539809

RESUMO

We have investigated the subcellular organization of the four human Y RNAs. These RNAs, which are transcribed by RNA polymerase III, are usually found complexed with the Ro autoantigen, a 60-kD protein. We designed 2'-OMe oligoribonucleotides that were complementary to accessible single-stranded regions of Y RNAs within Ro RNPs and used them in fluorescence in situ hybridization. Although all four Y RNAs were primarily cytoplasmic, oligonucleotides directed against three of the RNAs hybridized to discrete structures near the nucleolar rim. We have termed these structures "perinucleolar compartments" (PNCs). Double labeling experiments with appropriate antisera revealed that PNCs are distinct from coiled bodies and fibrillar centers. Co-hybridization with a genomic DNA clone spanning the human Y1 and Y3 genes showed that PNCs are not stably associated with the transcription site for these Y RNAs. Although 5S rDNA was often located near the nucleolar periphery, PNCs are not associated with 5S gene loci. Two additional pol III transcripts, the RNA components of RNase P and RNase MRP, did colocalize within PNCs. Most interestingly, the polypyrimidine tract-binding protein hnRNP I/PTB was also concentrated in this compartment. Possible roles for this novel nuclear subdomain in macromolecular assembly and/or nucleocytoplasmic shuttling of these five pol III transcripts, along with hnRNP I/PTB, are discussed.


Assuntos
RNA Polimerase III/fisiologia , RNA/fisiologia , Ribonucleoproteínas/fisiologia , Sequência de Bases , Compartimento Celular , Sondas de DNA , Células HeLa , Ribonucleoproteínas Nucleares Heterogêneas , Humanos , Dados de Sequência Molecular , Estrutura Molecular , Pirimidinas/metabolismo , RNA/química , Transcrição Gênica
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