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1.
Environ Res ; 188: 109837, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32798954

RESUMO

Changes in environmental conditions, whether related or not to human activities, are continuously modifying the geographic distribution of vectors, which in turn affects the dynamics and distribution of vector-borne infectious diseases. Determining the main ecological drivers of vector distribution and how predicted changes in these drivers may alter their future distributions is therefore of major importance. However, the drivers of vector populations are largely specific to each vector species and region. Here, we identify the most important human-activity-related and bioclimatic predictors affecting the current distribution and habitat suitability of the mosquito Culex pipiens and potential future changes in its distribution in Spain. We determined the niche of occurrence (NOO) of the species, which considers only those areas lying within the range of suitable environmental conditions using presence data. Although almost ubiquitous, the distribution of Cx. pipiens is mostly explained by elevation and the degree of urbanization but also, to a lesser extent, by mean temperatures during the wettest season and temperature seasonality. The combination of these predictors highlights the existence of a heterogeneous pattern of habitat suitability, with most suitable areas located in the southern and northeastern coastal areas of Spain, and unsuitable areas located at higher altitude and in colder regions. Future climatic predictions indicate a net decrease in distribution of up to 29.55%, probably due to warming and greater temperature oscillations. Despite these predicted changes in vector distribution, their effects on the incidence of infectious diseases are, however, difficult to forecast since different processes such as local adaptation to temperature, vector-pathogen interactions, and human-derived changes in landscape may play important roles in shaping the future dynamics of pathogen transmission.


Assuntos
Culex , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Ecossistema , Humanos , Mosquitos Vetores , Espanha , Febre do Nilo Ocidental/epidemiologia
2.
Med Vet Entomol ; 30(2): 166-73, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26890285

RESUMO

The emerging disease West Nile fever is caused by West Nile virus (WNV), one of the most widespread arboviruses. This study represents the first test of the vectorial competence of European Culex pipiens Linnaeus 1758 and Stegomyia albopicta (= Aedes albopictus) (both: Diptera: Culicidae) populations for lineage 1 and 2 WNV isolated in Europe. Culex pipiens and S. albopicta populations were susceptible to WNV infection, had disseminated infection, and were capable of transmitting both WNV lineages. This is the first WNV competence assay to maintain mosquito specimens under environmental conditions mimicking the field (day/night) conditions associated with the period of maximum expected WNV activity. The importance of environmental conditions is discussed and the issue of how previous experiments conducted in fixed high temperatures may have overestimated WNV vector competence results with respect to natural environmental conditions is analysed. The information presented should be useful to policymakers and public health authorities for establishing effective WNV surveillance and vector control programmes. This would improve preparedness to prevent future outbreaks.


Assuntos
Aedes/virologia , Culex/virologia , Insetos Vetores/virologia , Febre do Nilo Ocidental/transmissão , Vírus do Nilo Ocidental/fisiologia , Animais , Culex/genética , Europa (Continente) , Feminino , Insetos Vetores/genética , Espanha , Vírus do Nilo Ocidental/genética
3.
Allergol Immunopathol (Madr) ; 44(1): 3-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26318414

RESUMO

BACKGROUND: We aimed to identify factors associated with recurrent wheezing (RW) in infants in the first year of life living in the Southern region of São Paulo city and participating in the "Estudio Internacional de Sibilancias en Lactantes (EISL)" - phase 3 (P3). METHODS: 1335 parents of infants who were attended in primary care health units in the Southern region of São Paulo city from 2009 to 2010 answered the EISL-P3 written questionnaire. The wheezing group was stratified in accordance to the frequency of wheezing episodes as occasional wheezing (OW, less than three episodes), or RW (three or more episodes). Wheezing-associated factors were evaluated using multivariate analysis and were expressed as odds ratio (OR) and 95% confidence interval (95%CI). RESULTS: The most relevant factors related to OW were pneumonia (OR=3.10, 95%CI=1.68-5.73), hospitalisation due to pneumonia (OR=2.88, 95%CI=1.26-6.56) and recurrent upper respiratory infection (URI, OR=1.87, 95%CI=1.25-2.81). Regarding RW, recurrent URI (OR=5.34, 95%CI=3.83-7.45), pneumonia (OR=4.06, 95%CI=2.87-5.74) and asthmatic siblings (OR=3.02, 95%CI=1.67-5.45) were the most significantly associated factors. CONCLUSIONS: In the present study, we found that recurrent URI, positive history of pneumonia and familiar history of asthma were the most relevant factors associated with RW. The precocious knowledge of these factors can enable the identification of the probable asthmatic infants and can improve both prevention strategies and treatment of these patients.


Assuntos
Asma/epidemiologia , Pneumonia/epidemiologia , Sons Respiratórios , Infecções Respiratórias/epidemiologia , Asma/complicações , Brasil , Hospitalização , Humanos , Lactente , Recém-Nascido , Cooperação Internacional , Pneumonia/complicações , Prevalência , Recidiva , Sons Respiratórios/etiologia , Infecções Respiratórias/complicações , Fatores de Risco , Irmãos , Inquéritos e Questionários
4.
J Endocrinol Invest ; 38(9): 951-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25740070

RESUMO

PURPOSE: Insulin-like growth factor I (IGF-I) represents an essential tool in the diagnostic work-up and in the monitoring of treatment efficacy for somatotrophic axis disorders both in children and adults. A large number of factors including, but not limited to, age, sex and weight as well as analytical variables influence IGF-I serum levels; therefore, reliable normative data are essential for a correct interpretation of results. The aim of the present study was to establish reference range values for serum IGF-I, in a large population of healthy adults from Buenos Aires city. METHODS: The study included serum samples from 1044 healthy subjects aged 21-87 years (423 females and 621 males) divided into groups by sex at 5-year intervals from 21 to >75 years. Serum IGF-I concentrations were determined by a fully automated two-site, solid-phase, enzyme-labeled chemiluminescent immunometric assay (Immulite 2000, Siemens Healthcare Diagnostics). IGF-BP interferences are circumvented by blocking IGF-BP binding sites with excess IGF-II in the on-board predilution step. RESULTS: Results show the age dependence of circulating IGF-I levels, with a smooth and steady decrease in levels with age. No sex differences were found in subjects >26 years; however, in the group aged 21-25 years, IGF-I levels were significantly higher in females. In conclusion, this study provides age- and gender-adjusted normal reference ranges for IGF-I levels obtained with an automated immunometric chemiluminescent assay Immulite 2000 in healthy adult subjects.


Assuntos
Transtornos do Crescimento/diagnóstico , Fator de Crescimento Insulin-Like I/análise , Medições Luminescentes/métodos , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Argentina , Feminino , Transtornos do Crescimento/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fatores Sexuais , Adulto Jovem
5.
Allergol Immunopathol (Madr) ; 43(5): 482-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25985710

RESUMO

INTRODUCTION: Asthma is an inflammatory disorder of the airways associated with bronchial hyperresponsiveness, airway obstruction, and increased mucus production, with a predominance of type 2 immune response (Th2). According to the hygiene hypothesis, exposure to environmental bacterial lipopolysaccharide (LPS) may induce a type 1 immune response (Th1), modulating the development of asthma. OBJECTIVE: In this study we investigated cytokine production by peripheral blood mononuclear cells (PBMC) from children and adolescents with severe asthma, in response to LPS stimulation in vitro. MATERIALS AND METHODS: 26 children were selected: 13 severe asthmatics and 13 healthy controls, aged between 5 and 18 years. They were evaluated through routine medical history, physical examination and lung function test to diagnose severe asthma. Allergy status was confirmed by skin prick test and specific IgE assay. We collected blood samples to analyse in vitro LPS-induced cytokines release by PBMC. RESULTS: PBMC from severe asthmatic children produced lower levels of IL-12p70 in basal conditions and after 12 and 24h stimulation with LPS compared to healthy controls. PBMC from severe asthmatic children produced lower levels of IL-4 after 24h LPS stimulation compared to healthy controls. PBMC from severe asthmatic children produced more levels IL-17 and IL-10 after stimulus with LPS compared to healthy controls. The release of IFN-γ, IL-5 and TNF-α by PBMC from severe asthmatic children was similar to healthy controls. CONCLUSION: Our results demonstrate that LPS directly influence the cytokine profile of PBMC in children with severe asthma. These observations may be potentially helpful in developing new treatment strategies.


Assuntos
Asma/imunologia , Interleucina-12/sangue , Interleucina-4/sangue , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/imunologia , Adolescente , Asma/microbiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interferon gama/sangue , Masculino , Índice de Gravidade de Doença
6.
Allergol Immunopathol (Madr) ; 43(3): 272-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25796303

RESUMO

BACKGROUND: PIDs are a heterogeneous group of genetic illnesses, and delay in their diagnosis is thought to be caused by a lack of awareness among physicians concerning PIDs. The latter is what we aimed to evaluate in Brazil. METHODS: Physicians working at general hospitals all over the country were asked to complete a 14-item questionnaire. One of the questions described 25 clinical situations that could be associated with PIDs and a score was created based on percentages of appropriate answers. RESULTS: A total of 4026 physicians participated in the study: 1628 paediatricians (40.4%), 1436 clinicians (35.7%), and 962 surgeons (23.9%). About 67% of the physicians had learned about PIDs in medical school or residency training, 84.6% evaluated patients who frequently took antibiotics, but only 40.3% of them participated in the immunological evaluation of these patients. Seventy-seven percent of the participating physicians were not familiar with the warning signs for PIDs. The mean score of correct answers for the 25 clinical situations was 48.08% (±16.06). Only 18.3% of the paediatricians, 7.4% of the clinicians, and 5.8% of the surgeons answered at least 2/3 of these situations appropriately. CONCLUSIONS: There is a lack of medical awareness concerning PIDs, even among paediatricians, who have been targeted with PID educational programmes in recent years in Brazil. An increase in awareness with regard to these disorders within the medical community is an important step towards improving recognition and treatment of PIDs.


Assuntos
Competência Clínica/estatística & dados numéricos , Síndromes de Imunodeficiência/epidemiologia , Médicos/estatística & dados numéricos , Brasil , Estudos Transversais , Cirurgia Geral , Hospitais Gerais , Humanos , Síndromes de Imunodeficiência/diagnóstico , Medicina Interna , Pediatria , Papel do Médico , Prática Profissional , Inquéritos e Questionários
7.
Forensic Sci Int ; 355: 111917, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38215538

RESUMO

More than three decades have passed since the publication of Lamendin et al.'s proposal in 1992. Over this time, numerous investigations have been conducted to assess the applicability of the technique in different populations with acceptable results in terms of estimation errors. The proposal by Lamendin and colleagues remains relevant today, and has made a significant contribution to adult age-at-death estimation due to its simplicity, repeatability, replicability, and high performance. Indeed, significant progress towards systematizing and strengthening the procedure has been reported in the published literature. One noteworthy advancement is the development of an international database that supports the use of Bayesian statistics for age-at-death estimation. This resource plays a crucial role in standardizing the methodology and improving the reliability for obtaining more reliable results on a global scale. The aim of this study is to investigate the historical evolution of the technique, to assess the accuracy of the results obtained by different analytic procedures, and to explore its impact in forensic applications through a systematic analysis of the specialized literature on this field. The current state of research indicates that this type of methodological research is an ongoing process, far from being completed. Many questions and challenges that require further attention to address effectively these issues remain unanswered, such as the development of non-linear regressions and probabilistic approaches, the deepening of procedures that improve global approximations, and the intensification of research focused on achieving more accurate estimations among individuals over 70 years-old. However, studies generally agree that the Lamendin technique works well for individuals between the ages of 30-60 years. It is still in force today, although the method has been significantly perfected. Despite the degree of research development in this area, further efforts are needed to improve the understanding and performance of these kinds of procedures. This will ultimately lead to an improvement in the accuracy and reliability of forensic investigation results worldwide.


Assuntos
Determinação da Idade pelos Dentes , Raiz Dentária , Adulto , Humanos , Pessoa de Meia-Idade , Idoso , Reprodutibilidade dos Testes , Teorema de Bayes , Determinação da Idade pelos Dentes/métodos
8.
Chemotherapy ; 59(1): 57-65, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23839011

RESUMO

BACKGROUND: Acinetobacter baumannii has evolved from an opportunistic pathogen into a common and persistent nosocomial bacterium capable of causing severe infections during endemic and epidemic periods. METHODS: The study period extended from January 1999 to December 2011 and involved patients hospitalized at the Hospital Civil de Guadalajara, Fray Antonio Alcalde, Jalisco, Mexico. From each patient, a single isolate was obtained, and a total of 3,680 unique isolates were collected. Susceptibility tests were performed according to the guidelines of the Clinical and Laboratory Standards Institute. RESULTS: A. baumannii has disseminated throughout the Hospital Civil de Guadalajara, Fray Antonio Alcalde, since 1999. A. baumannii isolates obtained from patients treated in the adult intensive care unit represent the majority of the isolates that have been collected. In addition, A. baumannii was isolated from the adult neurosurgical ward and the adult internal medicine ward, and these isolates were frequently obtained from secretions. A persistent decrease in the susceptibility of A. baumannii isolates to meropenem (92% in 1999 to 12% in 2011), imipenem and amikacin has been observed. CONCLUSIONS: A. baumannii became an endemic nosocomial pathogen during the study period at the Hospital Civil de Guadalajara, Fray Antonio Alcalde, and has exhibited a persistent decrease in susceptibility to all categories of antimicrobial agents over the past 13 years.


Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/isolamento & purificação , Acinetobacter baumannii/efeitos dos fármacos , Amicacina/farmacologia , Antibacterianos/farmacologia , DNA Bacteriano/análise , Eletroforese em Gel de Campo Pulsado , Humanos , Imipenem/farmacologia , Unidades de Terapia Intensiva , Meropeném , México , Testes de Sensibilidade Microbiana , Atenção Terciária à Saúde , Tienamicinas/farmacologia
9.
J Healthc Qual Res ; 38(5): 268-276, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-37003929

RESUMO

INTRODUCTION: In 2017, the Joint Commission proposed daily meetings called "huddle" as an indicator of quality of care. They are brief daily meetings of the multidisciplinary team, where security problems of the last 24h are shared and risks are anticipated. The objectives were to describe the most frequent safety events in Pediatric wards, implement improvements in patient safety, improve team communication, implement international safety protocols, and measure the satisfaction of the staff involved. MATERIAL AND METHODS: Prospective, longitudinal and analytical design (June 2020-February 2022), with previous educational intervention. Safety incidents, data related to unequivocal identification, allergy and pain records, data from the Scale for the Early Detection of Deficiencies (SAPI) and the Scale for the Secure Transmission of Information (SBAR) were collected. The degree of satisfaction of the professionals was evaluated. RESULTS: Three hundred forty-eight security incidents were recorded. Medication prescription or administration errors stood out (n=103). Drug prescription or administration errors stood out (n=103), especially those related to high-risk medication: acetaminophen (n=14) (×10 doses of acetaminophen; n=6), insulin (n=6), potassium (n=5) and morphic (n=5). An improvement was observed in the pain record; 5% versus 80% (P<.01), in the SAPI registry 5% versus 70% (P<.01), in SBAER scale 40% vs 100% (P<.01), in unequivocal identification of the patient 80% versus 100%; (P<.01) and in the application of analgesic techniques 60% versus 85% (P=.01). In the survey of professionals, a degree of satisfaction of 8 (7-9.5)/10 was obtained. CONCLUSIONS: Huddles made it possible to learn about security events in our environment and increase the safety of hospitalized patients, and improved communication and the relationship of the multidisciplinary team.


Assuntos
Acetaminofen , Equipe de Assistência ao Paciente , Humanos , Criança , Estudos Prospectivos , Pacientes , Dor
10.
Mar Biotechnol (NY) ; 24(3): 431-447, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35486299

RESUMO

Most members of the Pseudoalteromonas genus have been isolated from living surfaces as members of epiphytic and epizooic microbiomes on marine macroorganisms. Commonly Pseudoalteromonas isolates are reported as a source of bioactive exoproducts, i.e., secondary metabolites, such as exopolymeric substances and extracellular enzymes. The experimental conditions for the production of these agents are commonly associated with sessile metabolic states such as biofilms or liquid cultures in the stationary growth phase. Despite this, the molecular mechanisms that connect biofilm formation and the biosynthesis of exoproducts in Pseudoalteromonas isolates have rarely been mentioned in the literature. This review compiles empirical evidence about exoproduct biosynthesis conditions and molecular mechanisms that regulate sessile metabolic states in Pseudoalteromonas species, to provide a comprehensive perspective on the regulatory convergences that generate the recurrent coexistence of both phenomena in this bacterial genus. This synthesis aims to provide perspectives on the extent of this phenomenon for the optimization of bioprospection studies and biotechnology processes based on these bacteria.


Assuntos
Pseudoalteromonas , Biofilmes , Pseudoalteromonas/genética
11.
Vaccine ; 39(40): 5839-5844, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34465476

RESUMO

BACKGROUND: Low vaccination rates and under-detection of pertussis infections in adolescents and young adults have an impact on the transmission of pertussis to infants. In this study, the proportion of adolescents and young adults with IgG antibodies against B. pertussis antigens, representing recent infection or vaccination, was estimated in a population-based probabilistic survey in Mexico. METHODS: Sera and data from 1,581 subjects, including 1,102 adolescents and 479 young adults (10-19 and 20-25 years old, respectively) randomly selected from Mexico's 2012 National Health and Nutrition Survey, were analyzed. IgG antibodies against pertussis toxin (PT) were measured with the CDC/FDA ELISA. A subset of 234 samples was additionally tested with Bp-IgG PT ELISA kit (EUROIMMUN AG, Lubeck, Germany). Threshold values from corresponding test kits were used to identify recent infection or vaccination. RESULTS: Overall anti-PT IgG seroprevalence was 3.9% (95% CI: 2.3-6.3); 3.1% (95% CI: 1.9-5.0) in adolescents, and 4.9% (95% CI: 2.2-11) in young adults. Seroprevalence did not significantly vary by sex, socioeconomic status, region or rural/urban location. Compared to the CDC/FDA ELISA, the EUROIMMUN test showed a 76% sensitivity and 88% specificity. The weighted estimates represent a considerable burden of recent infection in adolescents and young adults; however, most adolescents and adults were seronegative and, therefore, susceptible to pertussis infection. CONCLUSION: Since booster vaccination to B. pertussis after toddlerhood is not recommended in the Mexican national policy, anti-PT IgG seropositivity may be reasonably attributed to recent infection. Assessing pertussis seroprevalence requires careful consideration of the diagnostic test threshold interpretation and epidemiological model used.


Assuntos
Bordetella pertussis , Coqueluche , Adolescente , Humanos , Lactente , México/epidemiologia , Inquéritos Nutricionais , Estudos Soroepidemiológicos , Coqueluche/diagnóstico , Coqueluche/epidemiologia , Adulto Jovem
12.
J Exp Med ; 179(2): 601-8, 1994 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8294870

RESUMO

Light microscopic studies of phagocytosis showed that Salmonella typhimurium entered mouse macrophages enclosed in spacious phagosomes (SP). Viewed by time-lapse video microscopy, bone marrow-derived macrophages exposed to S. typhimurium displayed generalized plasma membrane ruffling and macropinocytosis. Phagosomes containing Salmonella were morphologically indistinguishable from macropinosomes. SP formation was observed after several methods of bacterial opsonization, although bacteria opsonized with specific IgG appeared initially in small phagosomes that later enlarged. In contrast to macropinosomes induced by growth factors, which shrink completely within 15 min, SP persisted in the cytoplasm, enlarging often by fusion with macropinosomes or other SP. A Salmonella strain containing a constitutive mutation in the phoP virulence regulatory locus (PhoPc) induced significantly fewer SP. Similar to Yersinia enterocolitica, PhoPc bacteria entered macrophages in close-fitting phagosomes, consistent with that expected for conventional receptor-mediated phagocytosis. These results suggest that formation of SP contributes to Salmonella survival and virulence.


Assuntos
Macrófagos/microbiologia , Fagossomos/microbiologia , Pinocitose , Salmonella typhimurium/imunologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Células Cultivadas , Macrófagos/imunologia , Macrófagos/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Microscopia de Fluorescência , Mutação , Proteínas Opsonizantes , Fenótipo , Fotomicrografia , Salmonella typhimurium/genética , Gravação de Videoteipe
13.
Maturitas ; 137: 7-10, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32498939

RESUMO

Currently, there are major EU-based projects to better utilise wearables as useful diagnostic aids/tools in clinical settings as well for deployment in the home to capture ageing processes. To date, there has been little investigation of the translation of those tools beyond the geographical regions in which they were developed and implemented. Our objective was to examine pragmatic issues and challenges in the use of wearables in a diverse, low-resource, middle-income country like Brazil. We found barriers to their understanding and adoption converge on three themes: (i) regional inequalities; (ii) knowledge and resources; and (iii) trust. Current large-scale projects should consider the scalability and implementation of their methods, given those themes, facilitating a stratified and global approach to healthy ageing.


Assuntos
Países em Desenvolvimento , Marcha , Dispositivos Eletrônicos Vestíveis , Envelhecimento/fisiologia , Brasil , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Classe Social , Confiança
14.
Rev Sci Instrum ; 90(1): 014301, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30709208

RESUMO

The design and analysis of a device to measure the burst strength (strength under a state of pure radial internal pressure) and compliance of vascular grafts and flexible pressurized tubes is presented. The device comprises three main sections, viz., a clean air-dry pressure controller, a test specimen holder, and automated software for control and data collection. Air pressure is controlled by means of a valve and a dedicated mechanism allowing reaching up to 120 psi in increments of 1 psi, and recording pressure changes with 0.04 psi resolution. The circumferential strain is determined by measuring the radial displacement of the vascular graft using an optical arrangement capable of determining a maximum radial displacement of 10 mm with 0.02 mm resolution. The instrument provides a low uncertainty in compliance (±0.32%/100 mm Hg-1) and burst strength measurements. Due to its simplicity, the device can easily be reproduced in other laboratories contributing to a dedicated instrument with high resolution at low cost. The reliability of the apparatus is further confirmed by conducting finite element analysis, elasticity solutions for pressurized cylinders, and testing of small diameter vascular grafts made of a commercial aliphatic polyurethane tested under radial internal pressure.


Assuntos
Prótese Vascular , Desenho de Equipamento , Teste de Materiais/instrumentação , Pressão , Elasticidade , Análise de Elementos Finitos
15.
J Mech Behav Biomed Mater ; 79: 332-340, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29358151

RESUMO

The circumferential compliance and burst strength of vascular grafts are predicted through the conically modified von Mises and elasticity theories, providing an analytical closed form solution for both parameters. Besides the graft's radii, the model for circumferential compliance depends solely on the elastic modulus and Poisson's ratio of the polymer material, and its accuracy was verified by finite element analysis and measurements. The analytical expression of the burst strength requires accurate determination of the material's tensile and compressive yield stress, which were carefully obtained by using digital image correlation measurements in uniaxial tensile and compressive tests of the constitutive material. The average measured circumferential compliance and burst strength of an 8mm graft made of a commonly used biomaterial, Tecoflex® SG-80A, are 1.05%/100mmHg-1 and 34.1psi (1763mmHg) and the proposed analytical predictions fall within the experimental scattering. Thus, it is shown that the circumferential compliance and burst strength of vascular grafts can be analytically predicted by knowing the elastic and yield material properties accurately, without needing to actually test the graft under radial pressure. This is a major advantage which can aid in the design and tailoring of vascular grafts.


Assuntos
Prótese Vascular , Estresse Mecânico , Resistência à Tração , Módulo de Elasticidade , Elasticidade , Modelos Cardiovasculares , Pressão
17.
J Med Entomol ; 54(6): 1615-1625, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-28968769

RESUMO

We compared climatic distribution ranges between Aedes albopictus (Skuse) (Diptera: Culicidae) and the five wild (nondomesticated) species of Albopictus Subgroup of Scutellaris Group of Aedes (Stegomyia) in southern Asia. Distribution sites of the wild species concentrate in seasonal forest and savannah climate zones in India, Indochina, and southern China. The distribution of Ae. albopictus is broader than the wild species under 1) tropical rain-forest climate, 2) steppe and temperate savannah climate, and 3) continental climate with large seasonal temperature variation (hot summer and cold winter) at temperate lowlands (northernmost sites 40°N in Ae. albopictus vs 32°N in the wild species). However, the distribution of Ae. albopictus is more limited at tropical and subtropical highlands where the climate is cool but less continental (small seasonal variation, mild summer, and winter). We discuss a possibility that the broader climate ranges of Ae. albopictus are ecological or eco-evolutionary consequences of adaptation to human habitats. We also propose a general scenario for the origin, dispersal, and adaptation of Ae. albopictus in Asia as a hypothesis for future research.


Assuntos
Aedes , Distribuição Animal , Clima , Animais , Ásia
18.
Mol Microbiol ; 6(3): 301-308, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28776802

RESUMO

A Saccharomyces cerevisiae glutamate auxotroph, lacking NADP-glutamate dehydrogenase (NADP-GDH) and glutamate synthase (GOGAT) activities, was complemented with a yeast genomic library. Clones were obtained which still lacked NADP-GDH but showed GOGAT activity. Northern analysis revealed that the DNA fragment present in the complementing plasmids coded for a 1.5kb mRNA. Since the only GOGAT enzyme so far purified from S. cerevisiae is made up of a small and a large subunit, the size of the mRNA suggested that the cloned DNA fragment could code for the GOGAT small subunit. Plasmids were purified and used to transform Escherichia coli glutamate auxotrophs. Transformants were only recovered when the recipient strain was an E. coli GDH-less mutant lacking the small GOGAT subunit. These data show that we have cloned the structural gene coding for the yeast small subunit (GUS2). Evidence is also presented indicating that the GOGAT enzyme which is synthesized in the E. coli transformants is a hybrid comprising the large E. coli subunit and the small S. cerevisiae subunit.

19.
Oncol Rep ; 13(1): 115-20, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15583811

RESUMO

The main aim of this study was to evaluate the clinical relevance of Gelatinases in colorectal cancer (CRC). Ninety-five CRCs and their paired normal tissues were investigated to detect total levels of MMP-9, MMP-2, and the tissue inhibitors TIMP-1 and TIMP-2. Also, pro-MMP and MMP activity, and potential associations with clinical parameters were estimated. MMP-9, MMP-2 and TIMP-1 levels were greater in CRCs than in normal tissues, differences being significant for MMP-9 and TIMP-1. However, TIMP-2 showed significantly lower levels in tumour samples. Moreover, significant differences in the state of activation between gelatinases were found. TIMP-1 low levels were significantly associated with poor clinical outcome of patients. According to these data, different roles have to be attributed to MMP-2 and MMP-9 in CRC progression. Moreover, TIMP-1 level evaluation emerges as the main prognostic factor in relation to Gelatinases A and B activity in CRC.


Assuntos
Neoplasias Colorretais/diagnóstico , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Adenocarcinoma/diagnóstico , Adenocarcinoma/enzimologia , Adenocarcinoma/metabolismo , Idoso , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/metabolismo , Regulação para Baixo , Feminino , Humanos , Masculino , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Pessoa de Meia-Idade , Prognóstico , Inibidor Tecidual de Metaloproteinase-1/análise , Inibidor Tecidual de Metaloproteinase-2/análise , Regulação para Cima
20.
J Med Entomol ; 42(2): 180-6, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15799528

RESUMO

From October 1997 to September 1998, an entomological survey was carried out in Manhiça, Mozambique, to describe the anopheline population and intensity of malaria transmission. Ten different huts were randomly selected for entomological surveillance throughout the year. CDC light trap collections were conducted during three nights each month. Additional knockdown spraying catches were carried out in the morning, after the last catch. A total of 17,245 Culicinae and 1,251 Anophelinae were collected during the study. There was substantial house to house variation and seasonality in the distribution of Anophelinae population, with a peak in April towards the end of the warm and rainy season. Four species of genus Anopheles (Diptera: Culicidae) were described: Anopheles funestus Giles, Anopheles tenebrosus Dönitz, Anopheles arabiensis Patton, and Anopheles merus Dönitz. An. funestus constitutes 72.3% of the anopheline population. The estimated sporozoite rate was 1.2% and the average entomological inoculation rate for the area was 15 infective bites per person per year.


Assuntos
Anopheles , Insetos Vetores , Malária/transmissão , Animais , Anopheles/classificação , Anopheles/genética , Anopheles/parasitologia , Culicidae/classificação , Culicidae/parasitologia , Humanos , Mordeduras e Picadas de Insetos/epidemiologia , Moçambique/epidemiologia , Reação em Cadeia da Polimerase , Densidade Demográfica , População Rural , Estações do Ano
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