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1.
Opt Express ; 32(9): 16164-16181, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859252

RESUMO

Laser-induced filaments have been shown to reduce the voltage necessary to initiate electrical discharges in atmospheric air and guide their propagation over long distances. Here we demonstrate the stable generation of laser filament-guided electrical discharge columns in air initiated by high energy (up to 250 mJ) 1030 nm wavelength laser pulses of 7 ps duration at repetition rates up to 1 kHz and we discuss the processes leading to breakdown. A current proportional to the laser pulse energy is observed to arise as soon as the laser pulse arrives, initiating a high impedance phase of the discharge. Full breakdown, characterized by impedance collapse, occurs 100 ns to several µs later. A record 4.7-fold reduction in breakdown voltage for dc-biased discharges, which remains practically independent of the repetition rate up to 1 kHz, is observed to be primarily caused by a single laser pulse that produces a large (∼80%) density depression. The radial gaps between the filamentary plasma channel and the hollowed electrodes employed are shown to play a significant role in the breakdown dynamics. A rapid increase of 3-4 orders of magnitude in current is observed to follow the formation of localized radial current channels linking the filament to the electrodes. The increased understanding and control of kHz repetition rate filament-guided discharges can aid their use in applications.

2.
Foot Ankle Surg ; 14(3): 161-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19083636

RESUMO

BACKGROUND: Curettage of benign tumours commonly results in significant bone defects that are reconstructed with autologous grafts, allografts, bone cement or bone substitute. We have treated such defects in the talus without reconstruction with bone or any other material. We now report the healing of these ungrafted defects in eight patients treated with curettage for benign talar tumours. METHODS: Eight consecutive patients were reviewed retrospectively at a mean follow-up of 82 months (range: 28-180 months). Mean age was 21.7 years (range: 12.3-31.3 years) and mean defect size was 16.5 cm(3) (range: 3.5-48 cm(3)). Outcome measures included time to radiological consolidation, ankle pain and stiffness, talar collapse, and tibiotalar joint osteoarthritis. RESULTS: Full consolidation of the defect occurred within 6-12 months in all patients. One patient had minor discomfort over the scar, but there was no ankle joint pain. Two patients had some ankle stiffness, although one had established ankle osteoarthritis prior to surgery. No talar collapse, fracture or new significant osteoarthritis of the ankle was observed. CONCLUSIONS: We conclude that bone grafting is not a necessary adjunct to the curettage of talar lesions.


Assuntos
Neoplasias Ósseas/cirurgia , Tálus/cirurgia , Cicatrização , Adolescente , Adulto , Criança , Condroblastoma/cirurgia , Curetagem , Feminino , Seguimentos , Cistos Glanglionares/cirurgia , Humanos , Masculino , Osteoartrite/etiologia , Osteoblastoma/cirurgia , Complicações Pós-Operatórias , Estudos Retrospectivos , Adulto Jovem
3.
Sex Transm Infect ; 84 Suppl 1: i42-i48, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18647865

RESUMO

OBJECTIVE: To quantify the proportion of people living with HIV who are being affected by emergencies. METHODS: Emergencies were defined as conflict, natural disaster and/or displacement. Country-specific estimates of populations affected by emergencies were developed based on eight publicly available databases and sources. These estimates were calculated as proportions and then combined with updated country-level HIV estimates for the years 2003, 2005 and 2006 to obtain estimates of the number of men, women and children living with HIV who were also affected by emergencies. RESULTS: In 2006, 1.8 (range 1.3-2.5) million people living with HIV (PLHIV) were also affected by conflict, disaster or displacement, representing 5.4% (range 4.0-7.6%) of the global number of PLHIV. In the same year, an estimated 930 000 (range 660 000-1.3 million) women and 150 000 (range 110 000-230 000) children under 15 years living with HIV were affected by emergencies. In emergency settings, the estimated numbers of PLHIV in 2003 and 2005 were 2.6 million (range 2.0-3.4 million) and 1.7 million (range 1.4-2.1 million), respectively, representing 7.9% and 5.1% of the global number of PLHIV). CONCLUSIONS: These estimates provide a rationale to ensure that HIV interventions are integrated into rapid assessment of all emergency and preparedness and response plans to prevent HIV infections and address excess suffering, morbidity and mortality among these often overlooked vulnerable groups.


Assuntos
Desastres/estatística & dados numéricos , Infecções por HIV/epidemiologia , Refugiados/estatística & dados numéricos , Guerra , Adolescente , Adulto , Feminino , Saúde Global , Humanos , Masculino , Prevalência
4.
Ophthalmologe ; 105(7): 656-60, 2008 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-18415108

RESUMO

BACKGROUND AND PURPOSE: Early glaucomatous visual field defects can occur outside the central 30 degrees , which is usually examined in perimetric tests used for glaucoma diagnosis and screening. This study aimed to evaluate the diagnostic value of peripheral suprathreshold stimulation in open angle glaucoma before the development of reproducible visual field damage in standard 30 degrees automatic white-on-white perimetry. METHODS: A total of 352 eyes of 352 patients (ages 35-69 years; visual acuity 0.8 or better) from the Erlanger Glaucoma Registry were included in this study. They were divided into two groups: normal eyes and preperimetric glaucoma. All patients underwent a standardized glaucoma examination including Octopus 500EZ static perimetry (G1 program, all three phases); 95 eyes of 95 patients also received a 135-point suprathreshold test pattern of the Humphrey Field Analyzer (model 750i) for detecting peripheral visual field defects. Sensitivity and specificity were calculated for any single test point in phase 3 of the G1 test pattern and the Humphrey 135-point pattern. A score was calculated, and cluster analysis was performed. RESULTS: In 33 of 176 (18.8%) eyes with preperimetric glaucoma, the score was 3 or higher in phase 3 of the G1 program (normal eyes: 19 of 196; 9.7%). For both examination modalities, the highest sensitivity was found in test locations in the superior nasal midperiphery, corresponding to neuroretinal rim loss predominantly in the inferotemporal sector in early glaucomatous optic disc atrophy. CONCLUSION: Positive test results using suprathreshold stimulation in the midperiphery can be found in patients with preperimetric glaucoma at a significantly higher frequency than in normal subjects. Longitudinal studies will show whether such tests can be useful for predicting perimetric manifestation of the disease.


Assuntos
Glaucoma/diagnóstico , Estimulação Luminosa/métodos , Testes de Campo Visual/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Sex Transm Infect ; 84(supl): i42-i48, 2008. tab
Artigo em Inglês | Desastres | ID: des-17376

RESUMO

Objective: To quantify the proportion of people living with HIV who being infected by emergencies. Methods: Emergencies were defined as conflict, natural disaster and/or displacement. Country-specific estimates of populations affected by emergencies were developed based on eight publicly available databases and sources. These estimates were calculated as proportions and then combined with updated country-level HIV estimates for the years 2003, 2005 and 2006 to obtain estimated of hte number of men, women and children living with HIV who were also affected by emergencies. Results: In 2006, 1.8 (range 1.3-2.5) million people living with HIV (PLHIV) were also affected by conflict, disaster or displacement, representing 5.4% (range 4.0-7.6%) of the global number of PLHIV. In the same year, an estimated 930 000 (range 660 000-1.3 million) women and 150 000 (range 110 000-230 000) children under 15 years living wiht HIV were affected by emergencies . In emergency settings, the estimated numbers of PLHIV in 2003 and 2005 were 2.6 million (range 2.0-3.4 million) and 1.7 million (range 1.4-2.1 million), respectively, representing 7.9% abd 5.1% of the global number of PLHIV. Conclusions: These estimates provide a rationale to ensure that HIV interventions are integrated into rapid assessment of all emergency and preparedness and response plans to prevent HIV infections and address excess suffering, morbity and mortality among these often overlooled vulnerable groups. (AU)


Assuntos
Cuidados Médicos
6.
J Bone Joint Surg Br ; 89(9): 1144-8, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17905948

RESUMO

Patients considered suitable for total hip resurfacing arthroplasty often have bilateral disease. The peri-operative complications, transfusion requirements, hospital stay, outcome and costs in patients undergoing one-stage bilateral total hip resurfacing were compared with a group of patients undergoing a two-stage procedure. A total of 92 patients were included in the study, of which 37 (40%) had a one-stage and 55 (60%) had a two-stage resurfacing. There were no significant differences in age, gender, or American Society of Anaesthesiologists grade between the groups (p = 0.31, p = 0.23, p = 0.13, respectively). There were three systemic complications in the one-stage group (8.1%) and one in the two-stage group (1.8% of patients; 0.9% of procedures). There was no significant difference in the complication rate (p = 0.72) or the transfusion requirements (p = 0.32) between the two groups. The one-stage group had a reduced total hospital stay of five days (95% confidence interval 4.0 to 6.9; p < 0.001), reduced length of time to completion of all surgery of five months (95% confidence interval 2.6 to 8.3; p < 0.001), and the reduced cost was 35% less than that of a two-stage procedure. However, the total anaesthetic time was significantly longer for the one-stage group (p < 0.001; 95% confidence interval 31 to 52). This study demonstrates that consideration should be given to one-stage surgery for patients with bilateral symptomatic disease suitable for metal-on-metal hip resurfacing. A one-stage procedure appears to have benefits for both the patient and the hospital without additional complications.


Assuntos
Artroplastia de Quadril/métodos , Prótese de Quadril , Complicações Intraoperatórias , Complicações Pós-Operatórias , Adolescente , Adulto , Idoso , Artroplastia de Quadril/economia , Transfusão de Sangue , Criança , Intervalos de Confiança , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
Ophthalmologe ; 103(10): 866-72, 2006 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-16830139

RESUMO

BACKGROUND: Flicker light is an easy method to test sensory function after stress. The aim of this study was to determine the influence of flicker stress on temporal contrast sensitivity in healthy controls and patients with glaucomatous alteration of the optic disk. METHODS: A commercially available full-field stimulator (Retiport, Roland Consult) equipped with white LEDs was modified to perform psychophysical tests. The patients underwent measurements of the recovery time interval from cessation of flicker stress until recognition of a pregiven flicker contrast after photo stress. In addition, we studied contrast sensitivity with a continuous flickering target and with a flicker burst protocol avoiding adaptation to prevailing flicker. All tests were performed at a constant retinal illumination and at a frequency of 37 Hz for provocation as well as for contrast sensitivity tests. SUBJECTS: Normal healthy controls (40), "preperimetric" (62), and "perimetric" (52) open-angle glaucoma patients were studied. Exclusion criteria were age lower than 31 years, visual acuity under 0.6, and perimetric mean defect more than 9.5 dB. RESULTS: Recovery time after flicker stress was significantly longer in patients than in normals and longer in perimetric than in preperimetric patients. Analysis in perimetric patients revealed a larger area under ROC for the provocation test (0.95) than in contrast sensitivity tests (continuous flicker method: 0.90, flicker burst mode: 0.84). CONCLUSION: High-power LEDs which are installed in modern full-field devices can be used as a helpful tool to study psychophysical properties. In the present study it could be shown that threshold, adaptation, and recovery of temporal transfer characteristics are impaired in many patients with glaucoma.


Assuntos
Sensibilidades de Contraste , Fusão Flicker , Glaucoma/diagnóstico , Iluminação/métodos , Estimulação Luminosa/métodos , Testes de Campo Visual/métodos , Feminino , Humanos , Iluminação/instrumentação , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/instrumentação , Valores de Referência , Reprodutibilidade dos Testes , Semicondutores , Sensibilidade e Especificidade , Testes de Campo Visual/instrumentação
8.
Sex Transm Infect ; 82 Suppl 1: i42-7, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16581759

RESUMO

BACKGROUND: This paper brings together data from a variety of reports to provide a basis for assessing future steps for responding to and monitoring the HIV epidemic in Zimbabwe. METHOD: Data reported from four antenatal clinic (ANC) surveys conducted between 2000 and 2004, two small local studies in Zimbabwe conducted from 1997 through 2003, four general population surveys from 1999 through 2003, and service statistics covering 1990 through 2004 were used to describe recent trends in HIV prevalence and incidence, behaviour change, and programme provision. RESULTS: HIV prevalence among pregnant women attending ANCs declined substantially from 32.1% in 2000 to 23.9% in 2004. The local studies confirmed the decline in prevalence. However, prevalence continued to be high. Sexual behaviour data from surveys suggests a reduction in sexual experience before age 15 years among both males and females age 15-19 years, and in the proportions of males and females aged 15-29 years reporting non-regular sexual partners in the past 12 months. Reported condom use with non-regular partners has been high since 1999. Condom distribution and HIV counseling and testing increased from 2000 to 2004. DISCUSSION: On the basis of examination of data from a variety of sources, the recent decrease in HIV prevalence may be related to recent reductions in early-age sexual activity and non-regular sexual partnerships and increases in condom use. Comparison of data from sentinel surveillance systems, population based serosurveys, local studies, and service statistics provide increased confidence that a decline in HIV prevalence in Zimbabwe is actually happening in the population.


Assuntos
Infecções por HIV/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Adolescente , Adulto , Preservativos/estatística & dados numéricos , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Gravidez , Cuidado Pré-Natal , Prevalência , Vigilância de Evento Sentinela , Abstinência Sexual , Comportamento Sexual/estatística & dados numéricos , Zimbábue/epidemiologia
9.
Sex Transm Infect ; 78(5): 380-4, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12407246

RESUMO

OBJECTIVES: A survey was conducted to assess the adequacy of sexually transmitted infections (STI) prevention and control policies and programmes in the European region (including the central Asian republics). METHODS: An adapted World Health Organization (WHO) model questionnaire was sent to ministry of health officials in all 45 countries of Europe and central Asia. The questionnaire included questions on STI programme structure; STI case management; the different types and levels of services, including public and private service providers; partner notification and screening policies; services for vulnerable populations; monitoring and supervision; surveillance and research. RESULTS: Western European countries largely leave STI prevention and care to individual practitioners. Licensed providers exist at all levels of care, and access to consultations and treatment is usually free of charge. In the newly independent states (NIS), by contrast, programme efforts emphasise state guidance and supervision of local providers rather than individual practitioners. Access to services is limited in that in several NIS, only public sector specialists are licensed to treat STI. Formerly free of charge policies have been severely eroded. While in western Europe access to condoms appears to be good, in the NIS there are many fewer condom outlets. Regionwide, in 40% of countries the distribution of condoms is part of STI consultations. CONCLUSIONS: Non-availability of affordable high quality STI services, including STI treatment and condoms, may be one of the causes for the much higher STI prevalence in parts of eastern Europe and NIS than in western Europe.


Assuntos
Controle de Doenças Transmissíveis/organização & administração , Política de Saúde , Infecções Sexualmente Transmissíveis/prevenção & controle , Controle de Doenças Transmissíveis/economia , Preservativos/estatística & dados numéricos , Busca de Comunicante , Europa (Continente) , Honorários e Preços , Inquéritos Epidemiológicos , Humanos , Programas de Rastreamento/economia , Programas de Rastreamento/organização & administração , Setor Privado , Setor Público , Parceiros Sexuais , Infecções Sexualmente Transmissíveis/economia
10.
Reprod Health Matters ; 9(17): 11-5, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11468826

RESUMO

The World Health Organization (WHO) defines adolescents as persons between 10 and 19 years of age. (WHO 1998) Although adolescents make up about 20 per cent of the world's population (of whom 85 per cent live in developing countries), they have traditionally been neglected as a distinct target group and subsumed under the promotion of family, women's and child welfare and health. This has at least partially been because adolescents were seen as a relatively healthy age group, one that did not have a heavy 'burden of disease', at least as compared with young infants or older adults. However, there is increasing recognition that adolescents have special health-related vulnerabilities. Among the major causes of morbidity and mortality in young people are suicide, road accidents, tobacco use and sexual and reproductive ill-health. (WHO 1998) Furthermore, adolescents are increasingly seen as 'gateways to health' because behavioural patterns acquired during this period tend to last throughout adult life--roughly 70 per cent of premature deaths among adults are due to behaviours initiated in adolescence. (WHO 1998) This paper describes the social, economic, cultural, legal and health issues which affect the experience of adolescence. It shows that while young people around the world may experience the same physical changes and sensations during adolescence, the manner in which these are interpreted and give rise to social and legal prescriptions varies tremendously.


Assuntos
Comportamento do Adolescente , Medicina Reprodutiva , Sexualidade , Adolescente , Criança , Países em Desenvolvimento , Feminino , Indicadores Básicos de Saúde , Humanos , Masculino , Classe Social , Organização Mundial da Saúde
11.
Reprod Health Matters ; 9(17): 170-83, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11468834

RESUMO

The World Health Organization (WHO) estimates that two-thirds of all STIs worldwide occur in young people--teenagers and those in their early twenties (WHO 1993, WHO 1995). The provision of STI services to these age groups should therefore be high on the agenda of STI programme planners and adolescent/young people's health programmers alike. However, attempts to promote the sexual health of young people have so far tended to focus on prevention, education and counselling, while the provision of services to those who have already faced the consequences of unprotected sexual activity, including pregnancy and STI, or sexual violence, has lagged behind. In 1999-2000 a review was commissioned by GTZ of the characteristics of adolescent sexuality, evidence of STI risk in adolescents, the profile of adolescents in need of STI care, types and evidence of success of different STI service delivery models for adolescents and the advantages and disadvantages of each of these, and to what extent a youth-specific approach to STI services or an STI-specific approach to adolescent health service delivery, is warranted. This review will be published jointly by GTZ and WHO with the title Sexually Transmitted Infections among Adolescents: The Need for Adequate Health Services. This is a shortened form of the Summary and Conclusions of this book.


Assuntos
Serviços de Saúde do Adolescente/organização & administração , Necessidades e Demandas de Serviços de Saúde , Infecções Sexualmente Transmissíveis/terapia , Adolescente , Adulto , Países Desenvolvidos , Países em Desenvolvimento , Serviços de Planejamento Familiar , Feminino , Humanos , Masculino , Modelos Organizacionais , Objetivos Organizacionais , Medicina Reprodutiva , Comportamento Sexual , Infecções Sexualmente Transmissíveis/epidemiologia , Classe Social , Organização Mundial da Saúde
12.
AIDS ; 15 Suppl 3: S13-22, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11421178

RESUMO

Injecting drug users (IDUs) should be considered a 'partially hidden population' at high risk for HIV infection. In almost all locations it should be possible to locate and conduct research with IDUs, but it will probably never be possible to enumerate or draw random samples from an IDU population. Surveillance research studies with IDUs should include risk behaviors, as surveillance of HIV infection only will not be sufficiently time sensitive, and be used to develop and refine HIV prevention programming for the population. Contacts with IDUs can be developed at multiple settings, including voluntary treatment programs, law enforcement settings, and through 'street outreach.' Each type of setting has different advantages, disadvantages and ethical concerns. HIV testing as part of surveillance also raises additional important ethical concerns. The primary risk behaviors that should be included in surveillance studies are 'sharing' of drug injection equipment, the potential for rapid partner change among risk partners, and sexual risk behavior. Additional important objectives for surveillance research include: (1) the size of the local IDU population, (2) patterns of drug use, (3) availability injection equipment, (4) participation in prevention activities, and (5) access to and use of anti-retroviral treatments. HIV incidence is an ultimate objective for surveillance research, but there are no currently available cost-efficient methods for studying HIV incidence, so estimation from indirect measurements is usually required.


Assuntos
Infecções por HIV/transmissão , Vigilância da População/métodos , Abuso de Substâncias por Via Intravenosa/complicações , Infecções por HIV/epidemiologia , Humanos , Incidência , Estudos Longitudinais , Programas de Troca de Agulhas/organização & administração , Assunção de Riscos , Estudos Soroepidemiológicos , Centros de Tratamento de Abuso de Substâncias , Abuso de Substâncias por Via Intravenosa/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/classificação
13.
J Clin Anesth ; 13(2): 103-11, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11331169

RESUMO

STUDY OBJECTIVES: To examine the effects of hydroxyethyl starch (HES) on renal function. DESIGN: Randomized, controlled trial. SETTING: Operating theatre of a university hospital. PATIENTS: 60 ASA physical status I and II male patients undergoing middle ear surgery. INTERVENTIONS: Patients received either lactated Ringer's solution (LRS) or one of three HES solutions. The HES solutions were administered in a dose of 15 mL/kg bodyweight (bw), the Ringer's solution in a dose of 60 mL/kg bw, after induction of anesthesia over a period of one hour. MEASUREMENTS: Blood and urine samples for hormone and enzyme tests were obtained at defined times before, during, and after surgery. Urine excretion, glomerular filtration rate (GFR), renal plasma flow, and routine hemodynamic parameters were measured simultaneously. MAIN RESULTS: There were no significant intergroup differences regarding GFR, renal plasma flow, or tubular and glomerular integrity as measured by specific proteins and enzymes (alpha-1-microglobulin, Tamm-Horsfall-protein, immunoglobulin G, and N-acetyl-beta-D-glucosaminidase). Arginine vasopressin decreased in all groups during and following anesthesia, aldosterone and plasma renin activity decreased only in the HES groups, and angiotensin II decreased only in the HES 200/0.5 group. Central venous pressure increased during fluid administration in the LRS group and returned to baseline sooner in the HES groups. CONCLUSIONS: Hydroxyethyl starch administration appears to be risk-free with regard to renal function in patients without preexisting renal dysfunction who undergo general anesthesia. The relevance of the decrease in aldosterone following HES therapy needs further investigation.


Assuntos
Derivados de Hidroxietil Amido/efeitos adversos , Rim/efeitos dos fármacos , Substitutos do Plasma/efeitos adversos , Adulto , Idoso , Anestesia , Biomarcadores , Pressão Venosa Central/efeitos dos fármacos , Creatinina/urina , Orelha Média/cirurgia , Taxa de Filtração Glomerular/efeitos dos fármacos , Hormônios/sangue , Humanos , Soluções Isotônicas , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Circulação Renal/efeitos dos fármacos , Solução de Ringer , Urodinâmica/efeitos dos fármacos
15.
Mol Cell Biol ; 21(6): 2118-32, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11238946

RESUMO

Migration of cells requires interactions with the extracellular matrix mediated, in part, by integrins, proteases, and their receptors. Previous studies have shown that beta(3)-integrin interacts with the urokinase-type plasminogen activator receptor (u-PAR) at the cell surface. Since integrins mediate signaling into the cell, the current study was undertaken to determine if in addition beta(3)-integrin regulates u-PAR expression. Overexpression of beta(3)-integrin in CHO cells, which are avid expressers of the receptor, downregulated u-PAR protein and mRNA expression. The u-PAR promoter (-1,469 bp) that is normally constitutively active in CHO cells was downregulated by induced beta(3)-integrin expression. A region between -398 and -197 bp of the u-PAR promoter was critical for beta(3)-integrin-induced downregulation of u-PAR promoter activity. Deletion of the PEA3/ets motif at -248 bp substantially impaired the ability of beta(3)-integrin to downregulate the u-PAR promoter, suggesting that the PEA3/ets site acts as a silencing element. An expression vector encoding the transcription factor PEA3 caused inhibition of the wild-type but not the PEA3/ets-deleted u-PAR promoter. The PEA3/ets site bound nuclear factors from CHO cells specifically, but binding was enhanced when beta(3)-integrin was overexpressed. A PEA3 antibody inhibited DNA-protein complex formation, indicating the presence of PEA3. Downregulation of the u-PAR promoter was achieved by the beta(3)A-integrin isoform but not by other beta(3)-integrin isoforms and required the cytoplasmic membrane NITY(759) motif. Moreover, overexpression of the short but not the long isoform of the beta(3)-integrin adapter protein beta(3)-endonexin blocked u-PAR promoter activity through the PEA3/ets binding site. Thus, besides the physical interaction of beta(3)-integrin and u-PAR at the cell surface, beta(3) signaling is implicated in the regulation of u-PAR gene transcription, suggesting a mutual regulation of adhesion and proteolysis receptors.


Assuntos
Antígenos CD/metabolismo , Glicoproteínas da Membrana de Plaquetas/metabolismo , Receptores de Superfície Celular/genética , Sequências Reguladoras de Ácido Nucleico , Transcrição Gênica , Sequência de Aminoácidos , Animais , Antígenos CD/genética , Sequência de Bases , Sítios de Ligação , Células CHO , Cricetinae , Citoplasma/metabolismo , Regulação para Baixo , Regulação da Expressão Gênica , Integrina beta3 , Dados de Sequência Molecular , Proteínas Nucleares , Glicoproteínas da Membrana de Plaquetas/genética , Regiões Promotoras Genéticas , Estrutura Terciária de Proteína , Proteínas/genética , Proteínas/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
17.
Obstet Gynecol ; 96(4): 582-7, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11004363

RESUMO

OBJECTIVE: To investigate whether the activity of the three mitogen-activated protein kinases (Jun aminoterminal kinase, extracellular regulated kinase, and p38) is altered in placental tissue of women with preeclampsia and hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome. METHODS: Placental activity (measured by immunoprecipitation-kinase assay) and protein expression (measured by western blot) of Jun aminoterminal kinase, extracellular regulated kinase, and p38 mitogen-activated protein kinase were measured in four groups of eight women each with preeclampsia, HELLP syndrome, and normal vaginal or cesarean deliveries. To further characterize the Jun aminoterminal kinase signal transduction pathway, phosphorylation of c-Jun, a downstream effector of Jun aminoterminal kinase- mitogen-activated protein kinase, was analyzed by western blotting, and the activity of Rac1, an upstream activator of the Jun aminoterminal kinase signaling pathway, was determined by pull-down assay. RESULTS: The activity of Jun aminoterminal kinase was significantly lower in placentas of women with preeclampsia or HELLP syndrome compared with those who had normal vaginal or cesarean delivery, whereas levels of Jun aminoterminal kinase protein expression were similar. Phosphorylation of the transcription factor c-Jun and Rac1 activity also were significantly lower in women with preeclampsia and HELLP than in controls. p38 mitogen-activated protein kinase activity was significantly higher in women with preeclampsia than with HELLP syndrome. There was no change in extracellular regulated kinase activity or protein expression between subgroups. CONCLUSION: In placentas of women with preeclampsia or HELLP syndrome, a Rac1-Jun aminoterminal kinase-c-Jun-dependent signal transduction pathway was downregulated.


Assuntos
Proteínas Quinases Ativadas por Mitógeno/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Transdução de Sinais , Adulto , Regulação para Baixo , Feminino , Síndrome HELLP/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno , Gravidez , Proteínas Quinases p38 Ativadas por Mitógeno , Proteínas rac de Ligação ao GTP/metabolismo
18.
Bull World Health Organ ; 78(5): 628-39, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10859857

RESUMO

It has been widely believed that, by combining the services for preventing and treating sexually transmitted infections (STI) with those for family planning (FP), STI coverage would increase and the combined service would be of higher quality and more responsive to the needs of women. So far, there is little concrete evidence that integration has had such an impact. Besides the absence of documentation, a clear definition of integration is lacking. We therefore carried out a comprehensive review of concrete experiences with integrated services, and present a summary of our findings in this article. The results indicate that the tasks of STI prevention, such as education for risk reduction and counselling, have been integrated into family planning services much more frequently than the tasks of STI diagnosis and treatment. Some STI/FP integration efforts appear to have been beneficial, for instance when the integration of STI/HIV prevention had a positive impact on client satisfaction, and on the acceptance of family planning. Less clear is whether STI prevention, when concentrated among traditional FP clients, is having a positive impact on STI risk behaviours or condom use. A few projects have reported increases in STI caseloads following integration. In some projects, FP providers were trained in STI case management, but few clients were subsequently treated.


Assuntos
Medicina Baseada em Evidências , Serviços de Planejamento Familiar/organização & administração , Saúde Pública , Infecções Sexualmente Transmissíveis/prevenção & controle , Infecções Sexualmente Transmissíveis/terapia , Prestação Integrada de Cuidados de Saúde/organização & administração , Feminino , Infecções por HIV/prevenção & controle , Infecções por HIV/terapia , Infecções por HIV/transmissão , Humanos
19.
Oncogene ; 19(26): 3013-20, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10871853

RESUMO

Rac1 is a member of the Ras superfamily of small guanosine triphosphatases (GTPases) that act as molecular switches to control cytoskeletal rearrangements and cell growth. Analogous to Ras, constitutively activating point mutations of Rac1 cause tumorigenic transformation of cell lines. However, there is no information about whether Rac1 is also mutated in vivo. After RT - PCR of Rac1, several clones of seven benign and 10 malignant breast cancer tissues as well as eight breast cancer cell lines were sequenced. Only single-nucleotide polymorphisms of Rac1 could be detected, and none of these corresponded to constitutively activating point mutations that have been used in cell lines for transformation. While sequencing Rac1 in breast tissues, a new Rac1 isoform with an insertion of 19 codons within the reading frame of Rac1 close to switch region II was identified and named Rac1b. The Rac1b protein acts like a fast cycling GTPase in GTP binding and hydrolysis assays. In Northern and Western blot experiments both Rac1 RNA and Rac1 protein had a significantly higher expression in breast cancer tissues compared to normal breast tissue samples. Immunohistochemical staining of Rac1 showed weak Rac1 expression in benign breast disease but high expression level in ductal carcinoma-in-situ, primary breast cancer, and lymph node metastases. In addition, breast tumor cells from patients with recurrent disease had Rac1 expression at the plasma membrane, suggesting activation of Rac1, in patients with aggressive breast cancer. Oncogene (2000).


Assuntos
Neoplasias da Mama/metabolismo , Isoformas de Proteínas/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Sequência de Bases , Doenças Mamárias/genética , Doenças Mamárias/metabolismo , Doenças Mamárias/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Divisão Celular , Primers do DNA , Feminino , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/metabolismo , Humanos , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Isoformas de Proteínas/genética , RNA Mensageiro/genética , Proteínas rac1 de Ligação ao GTP/genética
20.
Sex Transm Infect ; 76(5): 363-5, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11141852

RESUMO

BACKGROUND: Since the early 1990s, major syphilis epidemics have occurred in the Newly Independent States (NIS) of the former Soviet Union. The new and rapidly changing societal and economic conditions in these countries challenge their traditional approaches to the control of sexually transmitted infections (STI). Nevertheless, following a steady increase until 1997, reported syphilis incidence has declined during the past 3 years in most parts of the region. We examine these trends against a background of ongoing changes in service delivery, care seeking behaviour, and case finding practices. METHODS: National syphilis surveillance data reported to the WHO Regional Office for Europe were compiled and analysed, and supplemented with information presented at recent expert meetings and with results from ongoing research. RESULTS: Since 1997, reported syphilis incidence either stabilised or declined in many locations in the NIS, but further increased in others, especially in rural areas. Congenital syphilis continued to increase in all countries, except Latvia. The proportion of self presenting cases versus cases detected through screening declined, and so did notifications of early compared with late forms of syphilis. Patients increasingly seek care in the private formal and informal healthcare sectors which hardly participate in case reporting. CONCLUSIONS: Recent declines in syphilis notifications in the NIS are at least partially a reflection of a reduced intensity of active case finding and of changes in reporting completeness because of a shift in service utilisation from the public to the private/informal sectors. Syphilis rates are still high, indicating that both public and private sectors have to respond more efficiently to the needs of many people at risk of STI. The collection of serial STI prevalence data is recommended to be able to validate trends in notifications.


Assuntos
Doenças Endêmicas/estatística & dados numéricos , Sífilis/epidemiologia , Adolescente , Adulto , Ásia Central/epidemiologia , Busca de Comunicante/tendências , Atenção à Saúde/tendências , Notificação de Doenças/estatística & dados numéricos , Europa Oriental/epidemiologia , Feminino , Humanos , Incidência , Recém-Nascido , Masculino , Aceitação pelo Paciente de Cuidados de Saúde , Gravidez , Setor Privado , Sífilis Congênita/epidemiologia
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