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1.
BMC Infect Dis ; 23(1): 104, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36814192

RESUMO

BACKGROUND: Routinely collected population-wide health data are often used to understand mortality trends including child mortality, as these data are often available more readily or quickly and for lower geographic levels than population-wide mortality data. However, understanding the completeness and accuracy of routine health data sources is essential for their appropriate interpretation and use. This study aims to assess the accuracy of diagnostic coding for public sector in-facility childhood (age < 5 years) infectious disease deaths (lower respiratory tract infections [LRTI], diarrhoea, meningitis, and tuberculous meningitis [TBM]) in routine hospital information systems (RHIS) through comparison with causes of death identified in a child death audit system (Child Healthcare Problem Identification Programme [Child PIP]) and the vital registration system (Death Notification [DN] Surveillance) in the Western Cape, South Africa and to calculate admission mortality rates (number of deaths in admitted patients per 1000 live births) using the best available data from all sources. METHODS: The three data sources: RHIS, Child PIP, and DN Surveillance are integrated and linked by the Western Cape Provincial Health Data Centre using a unique patient identifier. We calculated the deduplicated total number of infectious disease deaths and estimated admission mortality rates using all three data sources. We determined the completeness of Child PIP and DN Surveillance in identifying deaths recorded in RHIS and the level of agreement for causes of death between data sources. RESULTS: Completeness of recorded in-facility infectious disease deaths in Child PIP (23/05/2007-08/02/2021) and DN Surveillance (2010-2013) was 70% and 69% respectively. The greatest agreement in infectious causes of death were for diarrhoea and LRTI: 92% and 84% respectively between RHIS and Child PIP, and 98% and 83% respectively between RHIS and DN Surveillance. In-facility infectious disease admission mortality rates decreased significantly for the province: 1.60 (95% CI: 1.37-1.85) to 0.73 (95% CI: 0.56-0.93) deaths per 1000 live births from 2007 to 2020. CONCLUSION: RHIS had accurate causes of death amongst children dying from infectious diseases, particularly for diarrhoea and LRTI, with declining in-facility admission mortality rates over time. We recommend integrating data sources to ensure the most accurate assessment of child deaths.


Assuntos
Doenças Transmissíveis , Infecções Respiratórias , Criança , Humanos , Lactente , Pré-Escolar , Causas de Morte , África do Sul/epidemiologia , Fonte de Informação , Setor Público , Diarreia
2.
Pharm Stat ; 17(5): 593-606, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29984474

RESUMO

This paper provides an overview of "Improving Design, Evaluation and Analysis of early drug development Studies" (IDEAS), a European Commission-funded network bringing together leading academic institutions and small- to large-sized pharmaceutical companies to train a cohort of graduate-level medical statisticians. The network is composed of a diverse mix of public and private sector partners spread across Europe, which will host 14 early-stage researchers for 36 months. IDEAS training activities are composed of a well-rounded mixture of specialist methodological components and generic transferable skills. Particular attention is paid to fostering collaborations between researchers and supervisors, which span academia and the private sector. Within this paper, we review existing medical statistics programmes (MSc and PhD) and highlight the training they provide on skills relevant to drug development. Motivated by this review and our experiences with the IDEAS project, we propose a concept for a joint, harmonised European PhD programme to train statisticians in quantitative methods for drug development.


Assuntos
Desenvolvimento de Medicamentos/educação , Educação de Pós-Graduação/métodos , Estatística como Assunto/educação , Comportamento Cooperativo , Currículo , Desenvolvimento de Medicamentos/estatística & dados numéricos , Indústria Farmacêutica/organização & administração , Europa (Continente) , Humanos , Setor Privado , Setor Público , Pesquisa/organização & administração
3.
Anaesthesia ; 77(7): 836, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35254668
4.
J Occup Environ Hyg ; 13(11): 847-65, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27115294

RESUMO

In 2009, a preliminary framework for how climate change could affect worker safety and health was described. That framework was based on a literature search from 1988-2008 that supported seven categories of climate-related occupational hazards: (1) increased ambient temperature; (2) air pollution; (3) ultraviolet radiation exposure; (4) extreme weather; (5) vector-borne diseases and expanded habitats; (6) industrial transitions and emerging industries; and (7) changes in the built environment. This article reviews the published literature from 2008-2014 in each of the seven categories. Additionally, three new topics related to occupational safety and health are considered: mental health effects, economic burden, and potential worker safety and health impacts associated with the nascent field of climate intervention (geoengineering). Beyond updating the literature, this article also identifies key priorities for action to better characterize and understand how occupational safety and health may be associated with climate change events and ensure that worker health and safety issues are anticipated, recognized, evaluated, and mitigated. These key priorities include research, surveillance, risk assessment, risk management, and policy development. Strong evidence indicates that climate change will continue to present occupational safety and health hazards, and this framework may be a useful tool for preventing adverse effects to workers.


Assuntos
Mudança Climática , Exposição Ocupacional/análise , Saúde Ocupacional/tendências , Temperatura , Geografia , Humanos , Medição de Risco , Estados Unidos
5.
IJTLD Open ; 1(7): 292-298, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39035425

RESUMO

BACKGROUND: The COVID-19 pandemic prompted strict public health measures to reduce SARS-CoV-2 transmission, potentially interrupting TB programmes in the Western Cape, South Africa. METHODS: We conducted a retrospective cohort study, estimating changes in new TB case rates and risk of death during TB-specific admissions within 6 months of TB first evidence, during the pre-pandemic (1 January 2019-26 March 2020) and after the implementation of public health and social measures (PHSM) periods (26 March 2020-30 September 2021), based on PHSM strictness. We used interrupted time series and logistic regression models to adjust for key characteristics. RESULTS: We found an average 22% reduction (95% CI 19-25) in monthly TB cases during the entire PHSM implementation period. Additionally, the risk of death during TB-specific admissions increased, with the adjusted odds ratio ranging across PHSM levels from 1.36 (95% CI 1.17-1.57) on Level 1 to 1.44 (95% CI 1.16-1.79) on Level 2 compared with the pre-pandemic period. CONCLUSIONS: There was a decline in the number of diagnosed TB cases and an increased risk of severe outcomes from 26 March 2020 to 30 September 2021 in the Western Cape. TB programme recovery strategies must be prioritised, and TB management programmes must be integrated into future pandemic responses.


CONTEXTE: La pandémie de COVID-19 a entraîné la mise en place de mesures de santé publique strictes afin de limiter la propagation du SRAS-CoV-2, ce qui risque de perturber les efforts de lutte contre la TB dans la province du Cap-Occidental, en Afrique du Sud. MÉTHODES: Une étude de cohorte rétrospective a été réalisée afin d'évaluer les variations des taux de nouveaux cas de TB et le risque de décès lors des admissions spécifiques à la TB dans les 6 mois suivant la première preuve de la maladie. Cette étude a été menée pendant deux périodes distinctes : la période prépandémique, allant du 1er janvier 2019 au 26 mars 2020, et la période post-mise en œuvre des mesures de santé publique et sociales (PHSM, pour l'anglais « public health and social measures ¼), allant du 26 mars 2020 au 30 septembre 2021. L'objectif était d'évaluer l'impact des PHSM sur ces indicateurs. Pour ce faire, des séries temporelles interrompues et des modèles de régression logistique ont été utilisés afin de prendre en compte les principales caractéristiques. RÉSULTATS: Au cours de la période de mise en œuvre des PHSM, nous avons observé une diminution moyenne de 22% (IC à 95% 19­25) des cas mensuels de TB. De plus, nous avons constaté une augmentation du risque de décès pendant les admissions pour TB, avec un rapport de cotes ajusté variant de 1,36 (IC à 95% ; 1,17­1,57) au niveau 1 des PHSM à 1,44 (IC à 95% ; 1,16­1,79) au niveau 2, par rapport à la période prépandémique. CONCLUSIONS: Entre le 26 mars 2020 et le 30 septembre 2021, il y a eu une baisse du nombre de cas de TB diagnostiqués dans la province du Cap-Occidental, mais le risque de résultats graves a augmenté pendant cette période. Les stratégies de rétablissement des programmes de lutte contre la TB doivent être prioritaires et les programmes de gestion de la TB doivent être intégrés dans les futures réponses à la pandémie.

6.
S Afr Med J ; 114(3): e1560, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38525574

RESUMO

BACKGROUND: The COVID-19 pandemic resulted in the implementation of strict public health and social measures (PHSMs) (including mobility restrictions, social distancing, mask-wearing and hand hygiene), limitations on non-essential healthcare services, and public fear of COVID-19 infection, all of which potentially affected transmission and healthcare use for other diseases such as lower respiratory tract infections (LRTIs). OBJECTIVE: To determine changes in LRTI hospital admissions and in-facility mortality in children aged <5 years in the Western Cape Province during the pandemic. METHODS: We conducted a retrospective analysis of LRTI admissions and in-facility deaths from January 2019 to November 2021. We estimated changes in rates and trends of LRTI admissions during the pandemic compared with pre-pandemic period using interrupted time series analysis, adjusting for key characteristics. RESULTS: There were 36 277 children admitted for LRTIs during the study period, of whom 58% were male and 51% were aged 28 days - 1 year. COVID-19 restrictions were associated with a 13% step reduction in LRTI admissions compared with the pre-COVID-19 period (incidence rate ratio (IRR) 0.87, 95% confidence interval (CI)) 0.80 - 0.94). The average LRTI admission trend increased on average by 2% per month during the pandemic (IRR 1.02, 95% CI 1.02 - 1.04). CONCLUSIONS: The COVID-19 surges and their associated measures were linked to declining LRTI admissions and in-facility deaths, likely driven by a combination of reduced infectious disease transmission and reduced use of healthcare services, with effects diminishing over time. These findings may inform future pandemic response policies.


Assuntos
COVID-19 , Infecções Respiratórias , Criança , Humanos , Masculino , Pré-Escolar , Feminino , Pandemias , Estudos Retrospectivos , África do Sul/epidemiologia , Setor Público , Infecções Respiratórias/epidemiologia
7.
Opt Express ; 21(7): 9113-22, 2013 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-23572000

RESUMO

We demonstrate strong-to-perfect absorption across a wide range of mid-infrared wavelengths (5-12µm) using a two-layer system consisting of heavily-doped silicon and a thin high-index germanium dielectric layer. We demonstrate spectral control of the absorption resonance by varying the thickness of the dielectric layer. The absorption resonance is shown to be largely polarization-independent and angle-invariant. Upon heating, we observe selective thermal emission from our materials. Experimental data is compared to an analytical model of our structures with strong agreement.


Assuntos
Germânio/química , Luz , Refratometria/métodos , Espalhamento de Radiação , Absorção , Impedância Elétrica , Desenho de Equipamento , Análise de Falha de Equipamento , Raios Infravermelhos , Teste de Materiais
8.
Parasite Immunol ; 34(7): 388-93, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22554071

RESUMO

About 225 million malaria cases have been reported worldwide in 2009, and one-third of the world's population is infected with parasitic helminths. As helminths and Plasmodium are co-endemic, concurrent infections frequently occur. Helminths have been shown to modulate the host's immune response; therefore, pre-existing helminth infections may interfere with the efficient immune response to Plasmodium. To study the interaction between helminths and Plasmodium, we established a murine model of co-infection using the gastrointestinal nematode Strongyloides ratti and Plasmodium yoelii. We show that a pre-existing Strongyloides infection slightly enhanced peak parasitemia and weight loss in P. yoelii-infected BALB/c mice, while disease progression was not altered in co-infected C57BL/6 mice. The Plasmodium-induced IFN-γ production and final clearance of Plasmodium infection were not affected by S. ratti co-infection in both C57BL/6 and BALB/c mice. Interestingly, the T helper cell (Th) 2 response induced by S. ratti was significantly suppressed upon P. yoelii co-infection. This suppressed Th2 response, however, was still sufficient to allow expulsion of S. ratti parasitic adults. Taken together, we provide evidence that simultaneous presence of helminth and protist parasites does not interfere with efficient host defence in our co-infection model although changes in Th responses were observed.


Assuntos
Malária/imunologia , Plasmodium yoelii/imunologia , Strongyloides ratti/imunologia , Estrongiloidíase/imunologia , Estrongiloidíase/parasitologia , Animais , Coinfecção/imunologia , Coinfecção/prevenção & controle , Modelos Animais de Doenças , Feminino , Tolerância Imunológica , Interferon gama/metabolismo , Malária/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Carga Parasitária , Parasitemia/parasitologia , Células Th2/imunologia
9.
Acta Anaesthesiol Belg ; 61(1): 43-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20593644

RESUMO

Ullrich syndrome is a rare congenital hypotonic-sclerotic muscular disorder in which affected children develop a slowly progressive scoliosis and contractures and limpness of joints. The disease causes increasingly invalidating contractures and hardening of the muscles of the neck and trunk. While this neuromuscular type of scoliosis is progressive, patients rarely attain the point of surgery due to their compromised general medical condition. This may explain the current lack of outcome data and the paucity of information on perioperative management for patients with Ullrich syndrome undergoing major surgery. The purpose of this report was therefore to describe our first experience with the perioperative and anesthetic management of a 15-year-old boy presenting with Ullrich syndrome and a secondary invalidating scoliosis. The specific challenges of this condition characterized by severe restrictive lung disease and a challenging airway abnormality are discussed.


Assuntos
Anestesia/métodos , Distrofias Musculares/congênito , Assistência Perioperatória , Escoliose/cirurgia , Adolescente , Humanos , Masculino , Distrofias Musculares/complicações , Escoliose/complicações , Síndrome
10.
Science ; 211(4481): 493-4, 1981 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-7455690

RESUMO

The opiate antagonist naloxone has been used to treat cats subjected to cervical spinal trauma. In contrast to saline-treated controls, naloxone treatment significantly improved the hypotension observed after cervical spinal injury. More critically, naloxone therapy significantly improved neurologic recovery. These findings implicate endorphins in the pathophysiology of spinal cord injury and indicate that narcotic antagonists may have a therapeutic role in this condition.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Naloxona/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Gatos , Modelos Animais de Doenças , Endorfinas/antagonistas & inibidores , Naloxona/farmacologia , Medula Espinal/irrigação sanguínea , Traumatismos da Medula Espinal/fisiopatologia
12.
Acta Anaesthesiol Belg ; 60(2): 101-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19594092

RESUMO

Acute and chronic pain are of major concern after orthopedic surgery. The increasing trend toward day case surgery induced the development of different techniques in postoperative pain control. One commonly used strategy in pain management after knee and shoulder joint surgery is the intra-articular (IA) use of local anesthetics (LA). Recent attention has been drawn to the possible toxicity on chondrocytes of local anesthetics. The aim of this manuscript is to evaluate and compare through literature review the existing evidence on the clinical use and possible adverse effects of intra-articular injection of local anesthetics peri-operatively.


Assuntos
Anestésicos Locais/administração & dosagem , Dor Pós-Operatória/tratamento farmacológico , Anestésicos Locais/efeitos adversos , Artroscopia , Cartilagem/efeitos dos fármacos , Humanos , Injeções Intra-Articulares , Joelho/cirurgia
13.
Scand J Immunol ; 67(6): 594-602, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18433404

RESUMO

Protection against intracellular pathogens is usually mediated by cytotoxic T lymphocytes (CTL). Induction of a protective CTL response for vaccination purposes has proven difficult because of the limited access of protein antigens or attenuated pathogens to the MHC class I presentation pathway. We show here that pH-sensitive PE/CHEMS liposomes can be used as a vehicle to efficiently deliver intact proteins for presentation by MHC class I. Mice immunized with listerial proteins encapsulated in such liposomes launched a strong CTL response and were protected against a subsequent challenge with L. monocytogenes. Remarkably, the CTL response was induced independently of detectable CD4(+) T cell help.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Lipossomos/imunologia , Listeria monocytogenes/imunologia , Listeriose/imunologia , Listeriose/prevenção & controle , Baço/imunologia , Subpopulações de Linfócitos T/citologia , Linfócitos T Citotóxicos/citologia , Linfócitos T Auxiliares-Indutores/citologia , Animais , Toxinas Bacterianas/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Citotoxinas/imunologia , Proteínas de Choque Térmico/imunologia , Proteínas Hemolisinas/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Humanos , Imunização , Injeções Intraperitoneais , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Knockout
14.
Acta Anaesthesiol Belg ; 59(4): 263-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19235525

RESUMO

Lactic acidosis is a common problem in the peri-operative period. During extensive surgery we frequently have an augmentation of lactic acid most often on the basis of hypoperfusion. Normally, a rise in serum lactate level causes a fall in blood pH, and this metabolic acidosis is accompanied by a high anion gap. In this case report a perioperative rise in lactic acid and an elevation in serum pH in a patient during meningeal tumour surgery is presented.


Assuntos
Acidose Láctica/etiologia , Hidratação/efeitos adversos , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Evolução Fatal , Feminino , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico/sangue , Pessoa de Meia-Idade , Assistência Perioperatória
15.
Mon Not R Astron Soc ; 474(2): 1453-1468, 2018 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-29755143

RESUMO

We present the first good evidence for exocomet transits of a host star in continuum light in data from the Kepler mission. The Kepler star in question, KIC 3542116, is of spectral type F2V and is quite bright at Kp = 10. The transits have a distinct asymmetric shape with a steeper ingress and slower egress that can be ascribed to objects with a trailing dust tail passing over the stellar disk. There are three deeper transits with depths of ≃ 0.1% that last for about a day, and three that are several times more shallow and of shorter duration. The transits were found via an exhaustive visual search of the entire Kepler photometric data set, which we describe in some detail. We review the methods we use to validate the Kepler data showing the comet transits, and rule out instrumental artefacts as sources of the signals. We fit the transits with a simple dust-tail model, and find that a transverse comet speed of ∼35-50 km s-1 and a minimum amount of dust present in the tail of ∼ 1016 g are required to explain the larger transits. For a dust replenishment time of ∼10 days, and a comet lifetime of only ∼300 days, this implies a total cometary mass of ≳ 3 × 1017 g, or about the mass of Halley's comet. We also discuss the number of comets and orbital geometry that would be necessary to explain the six transits detected over the four years of Kepler prime-field observations. Finally, we also report the discovery of a single comet-shaped transit in KIC 11084727 with very similar transit and host-star properties.

16.
J Clin Invest ; 90(6): 2496-501, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1469100

RESUMO

Changes in gonadotropins and gonadal steroids during sexual maturation in rats and humans are well documented but little is known about hypothalamic gonadotropin-releasing hormone (GnRH) gene expression in relation to these events. This study measured hypothalamic proGnRH mRNA, GnRH precursor, and fully processed GnRH from postnatal day 8 until day 62 in male rats. GnRH precursor increased on day 22, reached a peak on day 24, declined on day 25 and returned to infantile levels by day 28. A secondary rise in precursor occurred at about day 40 when testosterone levels increased. GnRH mRNA increased on day 22 and remained elevated over the study period to day 26. GnRH increased on day 24 and remained at this level until a secondary rise occurred coincident with the testosterone rise at about day 40. The ratio of GnRH precursor to GnRH was high until day 24 and was low from day 26 onwards, reflecting a maturation of the processing enzyme system between these 2 d. Thus, an abrupt increase in GnRH gene transcription (mRNA) occurs early in juvenile male rats (day 22), well before the onset of puberty. An increase in GnRH precursor accompanies these early changes and this is followed by the maturation of processing as evidenced by the rapid decline of precursor and increase in GnRH from day 24 onward.


Assuntos
Hormônio Liberador de Gonadotropina/genética , Maturidade Sexual , Fatores Etários , Animais , Expressão Gênica , Hipotálamo/fisiologia , Masculino , Precursores de Proteínas/metabolismo , RNA Mensageiro/genética , Ratos , Testosterona/sangue
17.
Handb Clin Neurol ; 140: 153-176, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28187798

RESUMO

Most ischemic strokes are managed on the ward or on designated stroke units. A significant proportion of patients with ischemic stroke require more specialized care. Several studies have shown improved outcomes for patients with acute ischemic stroke when neurocritical care services are available. Features of acute ischemic stroke patients requiring intensive care unit-level care include airway or respiratory compromise; large cerebral or cerebellar hemisphere infarction with swelling; infarction with symptomatic hemorrhagic transformation; infarction complicated by seizures; and a large proportion of patients require close management of blood pressure after thrombolytics. In this chapter, we discuss aspects of acute ischemic stroke care that are of particular relevance to a neurointensivist, covering neuropathology, neurodiagnostics and imaging, blood pressure management, glycemic control, temperature management, and the selection and timing of antithrombotics. We also focus on the care of patients who have received intravenous thrombolysis or mechanical thrombectomy. Complex clinical decision making in decompressive hemicraniectomy for hemispheric infarction and urgent management of basilar artery thrombosis are specifically addressed.


Assuntos
Cuidados Críticos/métodos , Acidente Vascular Cerebral/terapia , Isquemia Encefálica/complicações , Isquemia Encefálica/terapia , Humanos , Acidente Vascular Cerebral/etiologia
18.
J Natl Cancer Inst ; 88(15): 1054-9, 1996 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-8683636

RESUMO

BACKGROUND: We previously observed decreased p53 immunostaining over time in paraffin-embedded sections of ductal carcinoma in situ of the breast of women; these sections had been stored on slides at room temperature. This observation suggests that slide storage adversely affects p53-immuno-staining intensity and could result in spurious negative staining for p53 in patient samples. PURPOSE: The goals of this study were to determine the time course and factors influencing loss of p53 immunoreactivity and to investigate whether a similar loss of reactivity occurs with other antigens commonly used to study breast cancer. METHODS: Serial sections cut from 12 formalin-fixed, paraffin-embedded, p53-positive invasive ductal carcinomas of the breast were stored on slides at room temperature or at 4 degrees C, with or without an additional paraffin coating, for 2, 4, 8, or 12 weeks. For each case, freshly cut slides from the same block (day 0) and stored slides were simultaneously stained for p53 by use of an automated immunostainer. Slides cut from formalin-fixed, paraffin-embedded breast carcinomas and stored for 12 weeks were also stained for factor VIII-related antigen (n = 12), estrogen receptor (ER) (n = 9), and Bcl-2 protein (n = 9). The staining intensity of all slides was assessed by visual microscopic examination and was also quantified by image analysis. Quantitative results were expressed as a percentage (mean +/- standard error) of the staining intensity on day 0. Data were analyzed by the Friedman Repeated Measures Analysis of Variance on Ranks, with statistical significance set at two-sided P < .05. RESULTS: The intensity of p53 staining decreased over time in nine (75%) of the 12 cases studied. In three (or 25% of all cases studied) of the nine cases that showed decreased p53 staining, slides stored for 12 weeks were scored as p53 negative. Antigen loss on slides stored at 4 degrees C was significantly less than that on slides stored at room temperature at all time points (all P < .05). At 12 weeks, the average staining intensity of slides stored at 4 degrees C was 33.2% +/- 9% of that on day 0 compared with 8.4% +/- 3% of that on day 0 for slides stored at room temperature (P < .001). Paraffin coating of the sections did not significantly diminish antigen loss at either room temperature or 4 degrees C, except for slides stored at room temperature for 12 weeks. The intensity of factor VIII staining decreased in nine of 12 cases (average staining intensity, 37.3% +/- 6% of that on day 0 at 12 weeks; P = .0001). The intensity of ER and Bcl-2 staining decreased in all nine cases studied at 12 weeks (average staining intensity, 14.0% +/- 6% and 21.0% +/- 4% of that on day 0, respectively; P = .0001 for each). CONCLUSIONS AND IMPLICATIONS: Slide storage, particularly at room temperature, results in substantial loss of p53 reactivity, with some p53-positive cases becoming p53 negative after 12 weeks of storage. Substantial loss of immunoreactivity for factor VIII, ER, and Bcl-2 occurs on slides stored at room temperature for 12 weeks. Storage of unstained slides for up to 12 weeks may lead to false-negative immunostaining for p53 and other antigens.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Proteína Supressora de Tumor p53/análise , Fator VIII/análise , Feminino , Humanos , Imuno-Histoquímica , Proteínas de Neoplasias/análise , Parafina , Proteínas Proto-Oncogênicas/análise , Proteínas Proto-Oncogênicas c-bcl-2 , Receptores de Estrogênio/análise , Temperatura , Fatores de Tempo
19.
Science ; 352(6286): 687-90, 2016 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-27151863

RESUMO

Natural recombination combines pieces of preexisting proteins to create new tertiary structures and functions. We describe a computational protocol, called SEWING, which is inspired by this process and builds new proteins from connected or disconnected pieces of existing structures. Helical proteins designed with SEWING contain structural features absent from other de novo designed proteins and, in some cases, remain folded at more than 100°C. High-resolution structures of the designed proteins CA01 and DA05R1 were solved by x-ray crystallography (2.2 angstrom resolution) and nuclear magnetic resonance, respectively, and there was excellent agreement with the design models. This method provides a new strategy to rapidly create large numbers of diverse and designable protein scaffolds.


Assuntos
Simulação por Computador , Modelos Químicos , Engenharia de Proteínas/métodos , Proteínas/química , Proteínas/genética , Evolução Biológica , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Estrutura Secundária de Proteína
20.
J Neurosci ; 21(14): 5191-202, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11438594

RESUMO

Neuronal differentiation involves Rac and Cdc42 GTPases. alpha-Chimaerin, a Rac/Cdc42 regulator, occurs as alpha1- and alternatively spliced Src homology 2 (SH2) domain-containing alpha2-isoforms. alpha2-chimaerin mRNA was highly expressed in the rat embryonic nervous system, especially in early postmitotic neurons. alpha1-chimaerin mRNA was undetectable before embryonic day 16.5. Adult alpha2-chimaerin mRNA was restricted to neurons within specific brain regions, with highest expression in the entorhinal cortex. alpha2-chimaerin protein localized to neuronal perikarya, dendrites, and axons. The overall pattern of alpha2-chimaerin mRNA expression resembles that of cyclin-dependent kinase regulator p35 (CDK5/p35) which participates in neuronal differentiation and with which chimaerin interacts. To determine whether alpha2-chimaerin may have a role in neuronal differentiation and the relevance of the SH2 domain, the morphological effects of both chimaerin isoforms were investigated in N1E-115 neuroblastoma cells. When plated on poly-lysine, transient alpha2-chimaerin but not alpha1-chimaerin transfectants formed neurites. Permanent alpha2-chimaerin transfectants generated neurites whether or not they were stimulated by serum starvation, and many cells were enlarged. Permanent alpha1-chimaerin transfectants displayed numerous microspikes and contained F-actin clusters, a Cdc42-phenotype, but generated few neurites. In neuroblastoma cells, alpha2-chimaerin was predominantly soluble with some being membrane-associated, whereas alpha1-chimaerin was absent from the cytosol, being membrane- and cytoskeleton-associated, paralleling their subcellular distribution in brain. Transient transfection with alpha2-chimaerin mutated in the SH2 domain (N94H) generated an alpha1-chimaerin-like phenotype, protein partitioned in the particulate fraction, and in NGF-stimulated pheochromocytoma cell line 12 (PC12) cells, neurite formation was inhibited. These results indicate a role for alpha2-chimaerin in morphological differentiation for which its SH2 domain is vital.


Assuntos
Quimerina 1/biossíntese , Sistema Nervoso/metabolismo , Neuritos/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Envelhecimento/metabolismo , Processamento Alternativo/genética , Animais , Células COS , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Quimerina 1/análise , Quimerina 1/genética , Córtex Entorrinal/metabolismo , Hibridização In Situ , Camundongos , Mutagênese Sítio-Dirigida , Sistema Nervoso/química , Sistema Nervoso/embriologia , Sistema Nervoso/crescimento & desenvolvimento , Neuroblastoma/metabolismo , Especificidade de Órgãos , Células PC12 , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Frações Subcelulares/química , Transfecção , Domínios de Homologia de src/fisiologia
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