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1.
Space Sci Rev ; 216(5): 103, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32831412

RESUMO

The Electron Loss and Fields Investigation with a Spatio-Temporal Ambiguity-Resolving option (ELFIN-STAR, or heretoforth simply: ELFIN) mission comprises two identical 3-Unit (3U) CubeSats on a polar (∼93∘ inclination), nearly circular, low-Earth (∼450 km altitude) orbit. Launched on September 15, 2018, ELFIN is expected to have a >2.5 year lifetime. Its primary science objective is to resolve the mechanism of storm-time relativistic electron precipitation, for which electromagnetic ion cyclotron (EMIC) waves are a prime candidate. From its ionospheric vantage point, ELFIN uses its unique pitch-angle-resolving capability to determine whether measured relativistic electron pitch-angle and energy spectra within the loss cone bear the characteristic signatures of scattering by EMIC waves or whether such scattering may be due to other processes. Pairing identical ELFIN satellites with slowly-variable along-track separation allows disambiguation of spatial and temporal evolution of the precipitation over minutes-to-tens-of-minutes timescales, faster than the orbit period of a single low-altitude satellite (Torbit ∼ 90 min). Each satellite carries an energetic particle detector for electrons (EPDE) that measures 50 keV to 5 MeV electrons with Δ E/E < 40% and a fluxgate magnetometer (FGM) on a ∼72 cm boom that measures magnetic field waves (e.g., EMIC waves) in the range from DC to 5 Hz Nyquist (nominally) with <0.3 nT/sqrt(Hz) noise at 1 Hz. The spinning satellites (Tspin ∼ 3 s) are equipped with magnetorquers (air coils) that permit spin-up or -down and reorientation maneuvers. Using those, the spin axis is placed normal to the orbit plane (nominally), allowing full pitch-angle resolution twice per spin. An energetic particle detector for ions (EPDI) measures 250 keV - 5 MeV ions, addressing secondary science. Funded initially by CalSpace and the University Nanosat Program, ELFIN was selected for flight with joint support from NSF and NASA between 2014 and 2018 and launched by the ELaNa XVIII program on a Delta II rocket (with IceSatII as the primary). Mission operations are currently funded by NASA. Working under experienced UCLA mentors, with advice from The Aerospace Corporation and NASA personnel, more than 250 undergraduates have matured the ELFIN implementation strategy; developed the instruments, satellite, and ground systems and operate the two satellites. ELFIN's already high potential for cutting-edge science return is compounded by concurrent equatorial Heliophysics missions (THEMIS, Arase, Van Allen Probes, MMS) and ground stations. ELFIN's integrated data analysis approach, rapid dissemination strategies via the SPace Environment Data Analysis System (SPEDAS), and data coordination with the Heliophysics/Geospace System Observatory (H/GSO) optimize science yield, enabling the widest community benefits. Several storm-time events have already been captured and are presented herein to demonstrate ELFIN's data analysis methods and potential. These form the basis of on-going studies to resolve the primary mission science objective. Broad energy precipitation events, precipitation bands, and microbursts, clearly seen both at dawn and dusk, extend from tens of keV to >1 MeV. This broad energy range of precipitation indicates that multiple waves are providing scattering concurrently. Many observed events show significant backscattered fluxes, which in the past were hard to resolve by equatorial spacecraft or non-pitch-angle-resolving ionospheric missions. These observations suggest that the ionosphere plays a significant role in modifying magnetospheric electron fluxes and wave-particle interactions. Routine data captures starting in February 2020 and lasting for at least another year, approximately the remainder of the mission lifetime, are expected to provide a very rich dataset to address questions even beyond the primary mission science objective.

3.
Actas Dermosifiliogr (Engl Ed) ; 110(8): 626-636, 2019 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31202471

RESUMO

Dermatologic diagnosis and monitoring have been dependent largely on visual grading. A skin biopsy is performed in case of diagnostic uncertainty, but can be traumatic, and results are delayed due to time for specimen transport and processing. Biopsies also destroy specimens, prohibiting lesion evolution monitoring. In vivo reflectance confocal microscopy (RCM) offers a diagnostic alternative to skin biopsy. RCM captures real-time, high-resolution images, and has been piloted for the evaluation of various dermatologic conditions. Identification of unique RCM features may distinguish dermatoses with similar clinical morphologies. Allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD) are diagnosed by patch testing that currently uses a subjective scoring system. RCM has increasingly been studied for early detection and severity grading of CD. Common RCM features shared by ACD and ICD are stratum corneum disruption, vesicle formation, exocytosis, spongiosis, and parakeratosis. Features unique to ACD are vasodilation, increased epidermal thickness, intercellular edema, and acanthosis. Features unique to ICD are detached corneocytes and targetoid keratinocytes. This review summarizes the use of RCM in evaluating contact eccematous conditions and aims to spark future research and interest in this promising tool.


Assuntos
Dermatite Alérgica de Contato/diagnóstico por imagem , Dermatite Irritante/diagnóstico por imagem , Microscopia Confocal/métodos , Biópsia/efeitos adversos , Dermatite Alérgica de Contato/patologia , Dermatite Irritante/patologia , Diagnóstico Diferencial , Humanos
4.
Nat Commun ; 9(1): 945, 2018 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-29507321

RESUMO

Marine spatial planning (MSP) seeks to reduce conflicts and environmental impacts, and promote sustainable use of marine ecosystems. Existing MSP approaches have successfully determined how to achieve target levels of ocean area for particular uses while minimizing costs and impacts, but they do not provide a framework that derives analytical solutions in order to co-ordinate siting of multiple uses while balancing the effects of planning on each sector in the system. We develop such a framework for guiding offshore aquaculture (bivalve, finfish, and kelp farming) development in relation to existing sectors and environmental concerns (wild-capture fisheries, viewshed quality, benthic pollution, and disease spread) in California, USA. We identify > 250,000 MSP solutions that generate significant seafood supply and billions of dollars in revenue with minimal impacts (often < 1%) on existing sectors and the environment. We filter solutions to identify candidate locations for high-value, low-impact aquaculture development. Finally, we confirm the expectation of substantial value of our framework over conventional planning focused on maximizing individual objectives.


Assuntos
Aquicultura , Conservação dos Recursos Naturais , Ecossistema , Água do Mar , Geografia
6.
J Eur Acad Dermatol Venereol ; 32(9): 1450-1455, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29178552

RESUMO

BACKGROUND: The benign and malignant patterns of acral melanocytic naevi (AMN) and acral melanomas (AM) have been defined in a series of retrospective studies. A three-step algorithm was developed to determine when to biopsy acral melanocytic lesions. This algorithm has only been applied to a Japanese population. OBJECTIVES: Our study aimed to review the current management strategy of acral melanocytic lesions and to investigate the utility of the three-step algorithm in a predominately Caucasian cohort. METHODS: A retrospective search of the pathology and image databases at Mayo Clinic was performed between the years 2006 and 2016. Only cases located on a volar surface with dermoscopic images were included. Two dermatologists reviewed all dermoscopic images and assigned a global dermoscopic pattern. Clinical and follow-up data were gathered by chart review. All lesions with known diameter and pathological diagnosis were used for the three-step algorithm. RESULTS: Regular fibrillar and ridge patterns were more likely to be biopsied (P = 0.01). The majority of AMN (58.1%) and AM (60%) biopsied were due to physician-deemed concerning dermoscopic patterns. 39.2% of these cases were parallel furrow, lattice-like or regular fibrillar. When patients were asked to follow-up within a 3- to 6-month period, only 16.7% of the patients returned within that interval. The three-step algorithm would have correctly identified four of five AM for biopsy, missing a 6 mm, multicomponent, invasive melanoma. CONCLUSION: We found one major educational gap in the recognition of low-risk lesions with high rates of biopsy of the fibrillary pattern. Recognizing low-risk dermoscopic patterns could reduce the rate of biopsy of AMN by 23.3%. We identified two major practice gaps, poor patient compliance with follow-up and the potential insensitivity of the three-step algorithm to small multicomponent acral melanocytic lesions.


Assuntos
Dermoscopia , Doenças do Pé/diagnóstico por imagem , Melanoma/diagnóstico por imagem , Segunda Neoplasia Primária/diagnóstico por imagem , Nevo Pigmentado/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico por imagem , Adulto , Idoso , Algoritmos , Biópsia , Dermoscopia/educação , Feminino , Doenças do Pé/patologia , Mãos , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Segunda Neoplasia Primária/patologia , Nevo Pigmentado/patologia , Estudos Retrospectivos , Pele/patologia , Neoplasias Cutâneas/patologia
8.
Behav Ther ; 47(5): 595-599, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27816073

RESUMO

A number of behavior therapists have proposed that depression results when a discriminative stimulus or reinforcer for behavior is removed. It is proposed here that the depressed person's general loss of interest in his environment suggests that there is a loss of reinforcer effectiveness. The manner in which environmental events, including the loss of a reinforcer, may result in this general loss of reinforcer effectiveness is discussed. The possible evolutionary significance of depression is also briefly discussed.

9.
QJM ; 109(6): 391-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26231089

RESUMO

BACKGROUND: Selecting outcome measures in cardiovascular prevention trials should be informed by their importance to selected populations. Major vascular event outcomes are usually prioritized in these trials with considerably less attention paid to cognitive and functional outcomes. AIM: To examine views on importance of outcome measures used in clinical trials. DESIGN: Cross-sectional survey. METHODS: Of 367 individuals approached, 280 (76%) participated: outpatients attending cardiovascular prevention clinics (n = 97), active retirement groups members (n = 75), medical students (n = 108). Participants were asked to rank, in order of importance, outcome measures, which may be included in cardiovascular prevention trials. Results were compared between two groups: <65s (n = 157) and ≥65s (n = 104). RESULTS: When asked what outcomes were most important to measure in cardiovascular prevention trials, respondents reported: death (31.6%) stroke (28.5%), dementia (26.9%), myocardial infarction (MI) (7.9%) and requiring nursing home (NH) care (5.1%). When asked the most relevant outcomes regarding successful ageing respondents reported; maintaining independence (32.4%), avoiding major illness (24.3%), good family life (23.6%), living as long as possible (15.8%), avoiding NH care (3.1%) and contributing to society (0.8%) as most important. When asked what outcome concerned them most about the future, respondents reported: dementia (32.6%), dependence (30.4%), death (12.8%), stroke (12.5%), cancer (6.2%) requiring NH care (4.8%) and MI (0.7%). Maintaining independence was considered most important in younger and older cohorts. CONCLUSION: Cognitive and functional outcomes are important patient-relevant outcomes, sometimes more important than major vascular events. Incorporating these outcomes into trials may encourage patient participation and adherence to preventative regimens.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/psicologia , Pacientes/psicologia , Adulto , Distribuição por Idade , Idoso , Atitude do Pessoal de Saúde , Doenças Cardiovasculares/epidemiologia , Estudos Transversais , Feminino , Humanos , Irlanda/epidemiologia , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Participação do Paciente , Ensaios Clínicos Controlados Aleatórios como Assunto , Classe Social , Adulto Jovem
10.
J Clin Neurosci ; 19(3): 360-3, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22245278

RESUMO

Thrombolysis trials have recruited few patients aged ≥80 years, which has led to uncertainty about the likely risk-to-benefit profile in the elderly. Leukoaraiosis (LA) has been associated with hemorrhagic transformation (HT) and increases with advanced age. We tested whether there were any independent associations between age, LA and HT. Consecutive patients treated with intravenous (IV) tissue plasminogen activator (tPA) were identified from a prospective database. LA on baseline CT scans was assessed by two independent raters using the modified Van Swieten Score (mVSS) (maximum score 8, severe >4). HT was assessed on routine 24 hour to 48 hour CT /MRI scans using the European Cooperative Acute Stroke Study criteria for hemorrhagic infarct (HI) or parenchymal hematoma (PH) and judged symptomatic by the treating neurologist as per Safe Implementation of Thrombolysis in Stroke criteria. There were 206 patients treated with IV tPA (mean age: 71.0 years; range: 24-92 years), of whom 65/206 (32%) were aged ≥80 years. Overall, HT occurred in 41/206 patients (20%), HI in 31, PH1 in four (one symptomatic) and PH2 in six (three symptomatic). Age was not associated with HT (any HT: odds ratio [OR]=1.01; 95% confidence interval [CI]=0.5-2.08; p=0.99; PH: OR=0.53; 95% CI=0.12-2.3; p=0.51). There was one patient with PH1 and one patient with PH2 in 65 patients ≥80 years, both asymptomatic. LA was present in 112/208 (54%), and severe in 16.5%. LA increased with age (p<0.001) but was not associated with PH (any LA: OR=0.83; 95% CI=0.25-2.8; p=0.99; severe LA: OR=0.54, 95% CI=0.09-3.5; p=0.99). Age ≥80 years or LA did not increase the risk of HT (including PH) after thrombolysis, although LA increased with age. Neither factor should exclude otherwise eligible patients from tPA treatment.


Assuntos
Idoso de 80 Anos ou mais/fisiologia , Hemorragia Cerebral/etiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Terapia Trombolítica/efeitos adversos , Adulto , Fatores Etários , Idoso , Isquemia Encefálica/complicações , Hemorragia Cerebral/epidemiologia , Feminino , Fibrinolíticos/administração & dosagem , Fibrinolíticos/uso terapêutico , Humanos , Injeções Intravenosas , Leucoaraiose/patologia , Modelos Logísticos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco , Ativador de Plasminogênio Tecidual/administração & dosagem , Ativador de Plasminogênio Tecidual/uso terapêutico , Tomografia Computadorizada por Raios X , Adulto Jovem
11.
Am J Physiol Lung Cell Mol Physiol ; 296(6): L1042-50, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19346433

RESUMO

Chronic alveolar hypoxia, whether due to residence at high altitude or lung disease, leads to a sustained increase in pulmonary vascular resistance and pulmonary hypertension (PH). Strategies that augment endogenous nitric oxide production or activity, including l-arginine supplementation, attenuate the development of PH. This action has been attributed to inhibition of vessel wall remodeling, thus preventing structural narrowing of the vascular lumen. However, more recent evidence suggests that structural changes are not responsible for the elevated vascular resistance observed in chronic hypoxic PH, calling into question the previous explanation for the action of l-arginine. We examined the effect of dietary l-arginine supplementation on pulmonary vasoconstriction, structurally determined maximum vascular lumen diameter, and vessel length in rats during 2 wk of exposure to hypoxia. l-Arginine attenuated the development of hypoxic PH by preventing increased arteriolar resistance. It did not alter mean maximal vascular lumen diameter, nor did it augment nitric oxide-mediated vasodilatation, in chronically hypoxic lungs. However, the total length of vessels within the gas exchange region of the hypoxic lungs was significantly increased after l-arginine supplementation. These findings suggest that dietary l-arginine ameliorated hypoxic PH, but not by an effect on the structurally determined lumen diameter of pulmonary blood vessels. l-Arginine enhanced angiogenesis in the hypoxic pulmonary circulation, which may attenuate hypoxic PH by producing new parallel vascular pathways through the lung.


Assuntos
Arginina/farmacologia , Hipertensão Pulmonar/tratamento farmacológico , Hipóxia/tratamento farmacológico , Neovascularização Fisiológica/efeitos dos fármacos , Circulação Pulmonar/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Doença Crônica , Hematócrito , Hipertensão Pulmonar/fisiopatologia , Hipóxia/fisiopatologia , Masculino , Óxido Nítrico/metabolismo , Ratos , Ratos Endogâmicos WKY , Fator A de Crescimento do Endotélio Vascular/metabolismo
12.
Cancer Chemother Pharmacol ; 64(3): 455-62, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19104814

RESUMO

RATIONALE: There is no standard second line therapy for relapsed oesophago-gastric (O-G) cancer. METHODS: We recruited 29 eligible patients with relapsed O-G cancer who had progressed during or within 3 months of prior chemotherapy to assess the efficacy and toxicity of capecitabine [2,000 mg/(m(2) day) on days 1-14] and irinotecan (250 mg/m(2)) given every 3 weeks. RESULTS: Five patients (17%) demonstrated objective response, while a further seven patients (24%) achieved disease stabilisation. Median progression-free survival and overall survival were 3.1 months (95% CI = 2.2-4.1 months) and 6.5 months (95%CI = 6-7.1 months), respectively. Among symptomatic patients, palliation of tumour-related symptoms included resolution of reflux (5/12 pts), dysphagia (3/9 pts) and weight loss (4/9 pts), improvements in anorexia (4/10 pts), nausea (3/4 pts), vomiting (4/6 pts) and pain (4/16 pts). Grade 3-4 toxicities were diarrhoea (15%), nausea and vomiting (7%), lethargy (31%), neutropenia (31%), anemia (14%) and thrombocytopenia (7%). CONCLUSIONS: Capecitabine and irinotecan has anti-tumour activity as second line treatment for relapsed O-G cancer, and provides an important improvement in disease related symptoms.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/fisiopatologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Carcinoma de Células Escamosas/fisiopatologia , Progressão da Doença , Intervalo Livre de Doença , Neoplasias Esofágicas/fisiopatologia , Junção Esofagogástrica/efeitos dos fármacos , Junção Esofagogástrica/fisiopatologia , Feminino , Humanos , Irinotecano , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neoplasias Gástricas/fisiopatologia , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
13.
J Drugs Dermatol ; 7(10): 940-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19112757

RESUMO

INTRODUCTION: Palmoplantar pustulosis (PPP) is a chronic, recurrent and difficult to treat skin condition characterized by the presence of pustules, erythema, and hyperkeratosis on palms and soles. METHODS: Fifteen subjects with PPP were randomized (2:1) to receive subcutaneous injections of either etanercept 50 mg or a placebo twice a week for 3 months. All subjects then received the etanercept 50 mg injections twice a week for an additional 3 months. RESULTS: Etanercept was well tolerated by subjects with PPP. The decrease in median Palmoplantar Pustulosis Area and Severity Index (PPPASI) score from baseline to 24 weeks was statistically significant for subjects treated with etanercept for 24 weeks (P = 0.038, n = 10) but not for subjects in the placebo/etanercept cross-over group (P = 0.125, n = 5). Comparison of changes in PPPASI from baseline to week 12 was not statistically significant for subjects assigned to etanercept or to placebo. Some subjects treated with etanercept presented good clinical improvements in PPP severity whereas others showed an increase in PPP severity. CONCLUSION: This study showed that etanercept was well tolerated in subjects with PPP and suggests that some PPP subjects might benefit from etanercept therapy. Larger studies are needed to assess PPP response to etanercept including the influence of smoking and the presence or absence of psoriasis outside palms and soles.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Imunoglobulina G/uso terapêutico , Psoríase/tratamento farmacológico , Receptores do Fator de Necrose Tumoral/uso terapêutico , Adulto , Anti-Inflamatórios não Esteroides/efeitos adversos , Método Duplo-Cego , Etanercepte , Feminino , Pé/patologia , Mãos/patologia , Humanos , Imunoglobulina G/efeitos adversos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Psoríase/patologia , Pele/patologia , Fumar/patologia , Adulto Jovem
14.
Appl Environ Microbiol ; 74(22): 6918-22, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18820060

RESUMO

A study of six child care centers was conducted to assess the microbiological quality of three food contact surfaces (one food serving surface and two food preparation surfaces) and one non-food contact surface (diaper changing surface) to determine the effectiveness of cleaning and sanitization procedures within the facilities. Aerobic plate counts (APCs) and Escherichia coli/coliform counts of 50-cm(2) areas on all surfaces were determined using standard microbiological swabbing methods. Samples were taken three times a day (preopening, lunchtime, and following final cleanup) twice per month for 8 months in each child care center (n = 288 sampling times). Mean log APCs over the survey period were 1.32, 1.71, 1.34, 1.96, 1.50, and 1.81 log CFU/50 cm(2) for the six centers. Mean log coliform counts were 0.15, 0.40, 0.33, 1.41, 0.28, and 1.12 CFU/50 cm(2) for the same centers. Coliforms were detected in 283 of 1,149 (24.7%) samples, with counts ranging from 1 to 2,000 CFU/50 cm(2), while E. coli was detected in 18 of 1,149 (1.6%) samples, with counts ranging from 1 to 35 CFU/50 cm(2). The findings of this study demonstrated that the extent of bacterial contamination was dependent on the center, time of day, and the area sampled. While no direct correlation between contamination and illness can be made, given the high risk of food-borne illness associated with children, microbial contamination of food contact or non-food contact surfaces is an aspect of food safety that requires more attention. Emphasis on training and the development of modified standard sanitation operating procedures for child care centers are needed to reduce potential hazards.


Assuntos
Bactérias/isolamento & purificação , Creches , Microbiologia Ambiental , Microbiologia de Alimentos , Pré-Escolar , Contagem de Colônia Microbiana , Enterobacteriaceae/isolamento & purificação , Escherichia coli/isolamento & purificação , Humanos , Lactente
15.
Proc Natl Acad Sci U S A ; 105(26): 8974-9, 2008 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18577590

RESUMO

Many nearshore fish and invertebrate populations are overexploited even when apparently coherent management structures are in place. One potential cause of mismanagement may be a poor understanding and accounting of stochasticity, particularly for stock recruitment. Many of the fishes and invertebrates that comprise nearshore fisheries are relatively sedentary as adults but have an obligate larval pelagic stage that is dispersed by ocean currents. Here, we demonstrate that larval connectivity is inherently an intermittent and heterogeneous process on annual time scales. This stochasticity arises from the advection of pelagic larvae by chaotic coastal circulations. This result departs from typical assumptions where larvae simply diffuse from one site to another or where complex connectivity patterns are created by transport within spatially complicated environments. We derive a statistical model for the expected variability in larval settlement patterns and demonstrate how larval connectivity varies as a function of different biological and physical processes. The stochastic nature of larval connectivity creates an unavoidable uncertainty in the assessment of fish recruitment and the resulting forecasts of sustainable yields.


Assuntos
Peixes/crescimento & desenvolvimento , Invertebrados/crescimento & desenvolvimento , Animais , Larva/crescimento & desenvolvimento , Larva/fisiologia , Estágios do Ciclo de Vida , Modelos Biológicos , Oceanos e Mares , Processos Estocásticos , Fatores de Tempo
16.
Genes Immun ; 9(3): 240-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18340362

RESUMO

Crohn's disease (CD) and ulcerative colitis (UC) are subforms of inflammatory bowel diseases (IBD). Genetic and environmental factors influencing the onset and course of the diseases have been recently identified. This study uses a two-step approach to detect genes involved in the pathogenesis of IBD by microarray analysis and real-time PCR (RT-PCR). In a first step, microarray expression screening was used to obtain tumour necrosis factor-alpha (TNF-alpha) induction profiles of two human cell lines to represent the tissue cell types involved in IBD. In a second step, a subset of differentially expressed genes was examined by real-time PCR in intestinal biopsy samples of normal controls (NC) compared with UC and CD patients, as well as to a cohort of patients suffering from intestinal diseases other than IBD. Data were obtained from 88 CD, 88 UC, 53 non-IBD patients (inflammatory control), DC and 45 NC individuals. The experimental design enabled the identification of disease-specific expressed genes. DnaJ (Hsp40) homologue, subfamily B, member 5 (DNAJB5) was downregulated in intestinal biopsy samples of the UC cohort compared with NC. A difference in JUNB expression levels was observed by comparing biopsy samples from inflamed and non-inflamed areas of UC patients. Transcript expression differences between IBD and control cohorts were found by examining histamine N-methyltransferase (HNMT), interleukin-1A (IL-1A) and proplatelet basic protein (PPBP) expression. The experimental procedure represents an approach to identify disease-relevant genes, which is applicable to any disease where appropriate model systems are available.


Assuntos
Cromossomos Humanos Par 4/genética , Regulação da Expressão Gênica , Doenças Inflamatórias Intestinais/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Primers do DNA/genética , Feminino , Proteínas de Choque Térmico HSP40/metabolismo , Humanos , Doenças Inflamatórias Intestinais/metabolismo , Interleucina-1alfa/metabolismo , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas c-jun/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , beta-Tromboglobulina/metabolismo
17.
Surg Innov ; 14(3): 168-76, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17928615

RESUMO

Although polypropylene has been used as a hernia repair material for nearly 50 years, very little science has been applied to studying the body's effect on this material. It is possible that oxidation of mesh occurs as a result of the chemical structure of polypropylene and the physiological conditions to which it is subjected; this leads to embrittlement of the material, impaired abdominal movement, and chronic pain. It is also possible that lightweight polypropylene meshes undergo less oxidation due to a reduced inflammatory reaction. The objective of this study was to characterize explanted hernia meshes using techniques such as scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, and compliance testing to determine whether the mesh density of polypropylene affects the oxidative degradation of the material. The hypothesis was that heavyweight polypropylene would incite a more intense inflammatory response than lightweight polypropylene and thus undergo greater oxidative degradation. Overall, the results support this theory.


Assuntos
Hérnia Abdominal/cirurgia , Próteses e Implantes , Varredura Diferencial de Calorimetria , Feminino , Humanos , Pessoa de Meia-Idade , Polipropilenos , Recidiva , Termogravimetria , Tomografia Computadorizada por Raios X
18.
J Biomed Mater Res B Appl Biomater ; 83(1): 44-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17285608

RESUMO

Hernia repair with prosthetic mesh significantly decreases the rate of recurrence compared with traditional, primary suture repair by reducing the tension on the edges of the wound. However, there are several complications associated with the use of mesh that may be due to the chronic inflammatory reaction to the mesh or a loss of compliance after degradation of the material. Mesh contraction and migration can also occur, sometimes resulting in a recurrent hernia. Based on the chemical structure of the polypropylene mesh material and the physiological conditions to which it is subjected, it is possible that oxidation is responsible for these changes in material properties. Oxidation would result in surface cracking, decreased melting temperature, loss of mass, and reduced compliance of the material. The objective of this study was to identify physiochemical changes in the surface and bulk properties of explanted polypropylene hernia meshes compared to pristine polypropylene mesh materials. Several characterization techniques were utilized, including scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, and compliance testing. Overall, the results supported our hypothesis that oxidation is involved with the degradation of polypropylene hernia mesh materials.


Assuntos
Materiais Biocompatíveis , Polipropilenos , Próteses e Implantes , Telas Cirúrgicas , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Hérnia Abdominal/cirurgia , Humanos , Teste de Materiais , Oxirredução , Polipropilenos/química , Polipropilenos/metabolismo , Desenho de Prótese , Estresse Mecânico , Propriedades de Superfície
19.
Hernia ; 11(3): 279-85, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17279319

RESUMO

Chronic infection of a prosthetic mesh implant is a severe complication of ventral hernia repair, and mesh explantation is usually required in these cases. Biologic mesh implants have a possible role in ventral hernia repair in this setting. Here we present a case of chronic mesh infection following ventral hernia repair and the use of a biologic mesh to repair the existing defect following explantation of the infected mesh. Analysis of the explant material demonstrated possible oxidative degradation of the original polypropylene. A review of the literature follows.


Assuntos
Materiais Biocompatíveis , Colágeno , Hérnia Ventral/cirurgia , Politetrafluoretileno/efeitos adversos , Implantação de Prótese/instrumentação , Infecções Relacionadas à Prótese/cirurgia , Telas Cirúrgicas/efeitos adversos , Seguimentos , Hérnia Ventral/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Implantação de Prótese/efeitos adversos , Infecções Relacionadas à Prótese/diagnóstico por imagem , Infecções Relacionadas à Prótese/etiologia , Reoperação , Telas Cirúrgicas/microbiologia , Tomografia Computadorizada por Raios X , Cicatrização
20.
Genes Immun ; 7(1): 11-8, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16222343

RESUMO

Linkage analyses have implicated chromosome 7p21.3 as a susceptibility region for inflammatory bowel disease (IBD). Recently, the mouse phenotype with diarrhea and goblet cell dysfunction caused by anterior gradient protein 2 dysfunction was reported (European patent WO2004056858). The genes encoding for the human homologues AGR2 and AGR3 are localized on chromosome 7p21.3. The gene structures were verified and mutation detection was performed in 47 IBD patients. A total of 30 single nucleotide polymorphisms (SNPs) were tested for association to ulcerative colitis (UC, N = 317) and Crohn's disease (CD, N = 631) in a German cohort and verified in a UK cohort of 384 CD and 311 UC patients. An association signal was identified in the 5' region of the AGR2 gene (most significant SNP hcv1702494, nominal P(TDT) = 0.011, P(case/control) = 0.0007, OR = 1.34, combined cohort). The risk haplotype carried an odds ratio of 1.43 in the German population (P = 0.002). AGR2 was downregulated in UC patients as compared to normal controls (P < 0.001) and a trend toward lower expression was seen in carriers of the risk alleles. Luciferase assays of the AGR2 promoter showed regulation by the goblet cell-specific transcription factors FOXA1 and FOXA2. In summary, AGR2 represents an interesting new avenue into the etiopathophysiology of IBD and the maintenance of epithelial integrity.


Assuntos
Proteínas de Transporte/genética , Predisposição Genética para Doença , Doenças Inflamatórias Intestinais/genética , Proteínas de Neoplasias/genética , Proteínas/genética , Proteínas de Transporte/biossíntese , Linhagem Celular , Colite Ulcerativa/genética , Colite Ulcerativa/metabolismo , Colite Ulcerativa/fisiopatologia , Doença de Crohn/genética , Doença de Crohn/metabolismo , Doença de Crohn/fisiopatologia , Fator 3-alfa Nuclear de Hepatócito/fisiologia , Fator 3-beta Nuclear de Hepatócito/fisiologia , Humanos , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/fisiopatologia , Mucoproteínas , Proteínas de Neoplasias/biossíntese , Proteínas Oncogênicas , Proteínas/metabolismo
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