RESUMO
BACKGROUND: Gay, bisexual and other men who have sex with men (GBMSM) are overrepresented in cohorts of people who inject drugs. GBMSM's substance use is usually explored in the context of its contribution to sexual risk. We examined drug use practices, connectedness to other people who inject drugs, peer-to-peer injecting, and access to care among men who inject drugs in Melbourne, Australia. We aim to describe similarities and differences in these parameters for GBMSM and other men. METHODS: Data were drawn from a prospective cohort study of people who inject drugs conducted in Melbourne, Australia, since 2009. This cross-sectional study used data collected between 2016 and 2021. Descriptive statistics were used to assess differences between GBMSM and other men. RESULTS: Of 525 men who injected drugs over the study period, 48 (9%) identified as gay or bisexual, or reported sex with other men in the past 12 months. GBMSM and other men reported similar socio-demographics, drug practices (age of injecting initiation, most injected drug, peer-to-peer injecting, receptive syringe sharing) and access to injecting-specific care (drug treatment, source of needle-syringes). A significantly greater percentage of GBMSM reported past 12-month hepatitis C testing (69% vs. 52%, p = 0.028) and preferring methamphetamine (31% vs. 16%, p = 0.022). A higher percentage of GBMSM reported knowing > 50 other people who inject drugs (46% vs. 37%), but this difference was not statistically significant. Both groups primarily obtained injecting equipment from needle-syringe programs; a minority had accessed injecting-specific primary care. CONCLUSION: Men who injected drugs in this cohort and those who identified as GBMSM reported similar drug and health-seeking practices. The higher prevalence of methamphetamine injecting among GBMSM may warrant different harm reduction support for this group. Health promotion should utilise opportunities to connect men who inject drugs in Melbourne to injecting-specific primary health care.
Assuntos
Metanfetamina , Minorias Sexuais e de Gênero , Abuso de Substâncias por Via Intravenosa , Transtornos Relacionados ao Uso de Substâncias , Masculino , Humanos , Abuso de Substâncias por Via Intravenosa/epidemiologia , Estudos Transversais , Homossexualidade Masculina , Estudos Prospectivos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Austrália/epidemiologiaRESUMO
Successful use of biomedical forms of HIV risk-reduction may have predisposed many gay and bisexual men (GBM) to vaccination against COVID-19, which may, in turn, affect their sexual behavior. A total of 622 Australian GBM provided weekly data on COVID-19 vaccination history and sexual behaviour between 17 January 2021 and 22 June 2021. We identify factors associated with COVID-19 vaccination, and compare sexual behavior before and since vaccination. Mean age was 47.3 years (SD 14.0). At least one-dose vaccination coverage had reached 57.2%, and 61.3% reported that the majority of their friends intended to be vaccinated. Vaccinated men reported a mean of 1.11 (SD 2.10) weekly non-relationship sex partners before vaccination and 1.62 (SD 3.42) partners following vaccination. GBM demonstrated high confidence in COVID-19 vaccines. Their sexual activity increased following vaccination suggesting that greater sexual freedom may be a specific motivation for vaccine uptake among some men.
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COVID-19 , Infecções por HIV , Minorias Sexuais e de Gênero , Austrália/epidemiologia , Bissexualidade , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , Pessoa de Meia-Idade , Comportamento Sexual , Parceiros SexuaisRESUMO
AIM: To synthesise the available evidence about the effects of modifications to diagnostic imaging reports that aim to optimise patient care. MATERIALS AND METHODS: Cochrane methods were used and CENTRAL, MEDLINE, EMBASE, and clinical trials registers were searched from inception to 31 March 2021. Randomised controlled trials of modifications to imaging reports aimed at optimising patient care for any condition were included. Two authors selected studies independently for inclusion, extracted data, assessed risk of bias, and judged certainty of evidence using GRADE. The primary outcome was quality of care (e.g., increased guideline-adherent care, reduced/increased imaging as appropriate). RESULTS: Five trials met eligibility criteria. One tested provision of information about appropriate osteoporosis treatment in bone density reports; two tested provision of criteria and treatment for heart failure in echocardiogram reports; one tested provision of reminders for when routine imaging is not needed in lumbar spine and knee radiography reports; and one tested inclusion of epidemiological data in lumbar spine imaging reports. All trials were susceptible to bias, and four did not blind all participants. Low certainty evidence from two trials found adding information about appropriate care may increase care quality compared to a standard report (RR 1.20 (95% CI 0.96 to 1.50), two trials, 1,548 participants, I2 = 49). This was supported by outcomes of two additional trials that also provided specific clinical guidance. CONCLUSIONS: The present review suggests that providing specific guidance on appropriate clinical intervention in imaging reports may improve patient care. Further high-quality trials are needed to confirm these findings. Prospective PROSPERO registration CRD42020153961.
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Densidade Óssea , Qualidade da Assistência à Saúde , Diagnóstico por Imagem , Humanos , Estudos Prospectivos , RadiografiaRESUMO
OBJECTIVES: SELPHI (HIV Self-Testing Public Health Intervention) is the largest randomized controlled trial (RCT) of HIV self-testing (HIVST) in a high-income setting to date, and has recruited 10 000 men who have sex with men (cis- and transgender) and transgender women who have sex with men. This qualitative substudy aimed to explore how those utilizing self-tests experience HIVST and the implications for further intervention development and scale-up. This is the first qualitative study in Europe investigating experiences of HIVST among intervention users, and the first globally examining the experience of using blood-based HIVST. METHODS: Thirty-seven cisgender MSM SELPHI participants from across England and Wales were purposively recruited to the substudy, in which semi-structured interviews were used to explore testing history, HIVST experiences and intervention preferences. Interviews were audio-recorded, transcribed and analysed through a framework analysis. RESULTS: Men accessed the intervention because HIVST reduced barriers related to convenience, stigma and privacy concerns. Emotional responses had direct links to acceptability. Supportive intervention components increased engagement with testing and addressed supportive concerns. HIVST facilitated more frequent testing, with the potential to reduce sexually transmitted infection (STI) screening frequency. Substudy participants with an HIV-positive result (n = 2) linked to care promptly and reported very high acceptability. Minor adverse outcomes (n = 2; relationship discord and fainting) did not reduce acceptability. Ease of use difficulties were with the lancet and the test processing stage. CONCLUSIONS: Intervention components shaped acceptability, particularly in relation to overcoming a perceived lack of support. The intervention was broadly acceptable and usable; participants expressed an unexpected degree of enthusiasm for HIVST, including those with HIV-positive results and individuals with minor adverse outcomes.
Assuntos
Detecção Precoce de Câncer/métodos , Infecções por HIV/diagnóstico , Homossexualidade Masculina/estatística & dados numéricos , Pessoas Transgênero/estatística & dados numéricos , Adolescente , Adulto , Países Desenvolvidos , Inglaterra , Estudos de Avaliação como Assunto , Feminino , Humanos , Entrevistas como Assunto , Masculino , Aceitação pelo Paciente de Cuidados de Saúde , Kit de Reagentes para Diagnóstico , Autoteste , País de Gales , Adulto JovemRESUMO
OBJECTIVES: There is considerable public health concern about the combining of sex and illicit drugs (chemsex) among gay men. With a view to inform supportive therapeutic and clinical interventions, we sought to examine the motivations for engaging in chemsex among gay men living in South London. METHODS: Community advertising recruited 30 gay men for qualitative semi-structured interview. Aged between 21 and 53â years, all lived in South London in the boroughs of Lambeth, Southwark and Lewisham and all had combined crystal methamphetamine, mephedrone and/or γ-hydroxybutyric acid/γ-butyrolactone with sex in the past 12â months. Transcripts were subjected to a thematic analysis. RESULTS: We broadly distinguished two groups of reasons for combining sex and drugs, within which we described eight distinct motivations. The first major group of motivations for combining drugs with sex was that drugs provide the means by which men can have the sex they desire by increasing libido, confidence, disinhibition and stamina. The second major group of motivations for chemsex was that drugs enhance the qualities of the sex that men value. Drugs made other men seem more attractive, increased physical sensations, intensified perceptions of intimacy and facilitated a sense of sexual adventure. CONCLUSION: Analysis revealed that sexualised drug use provides both motivation and capability to engage in the kinds of sex that some gay men value: sex that explores and celebrates adventurism. Those services providing (talking) interventions to men engaging in chemsex should consider these benefits of sexualised drug use alongside the harms arising.
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Conhecimentos, Atitudes e Prática em Saúde , Homossexualidade Masculina/psicologia , Motivação , Comportamento Sexual/efeitos dos fármacos , Comportamento Sexual/psicologia , Parceiros Sexuais/psicologia , Transtornos Relacionados ao Uso de Substâncias/psicologia , Adulto , Nível de Alerta/efeitos dos fármacos , Humanos , Drogas Ilícitas/efeitos adversos , Inibição Psicológica , Entrevistas como Assunto , Libido/efeitos dos fármacos , Londres , Masculino , Metanfetamina/administração & dosagem , Metanfetamina/efeitos adversos , Pessoa de Meia-Idade , Pesquisa Qualitativa , Assunção de Riscos , Adulto JovemRESUMO
OBJECTIVE: To critically appraise and compare the measurement properties of self-administered patient-reported outcome measures (PROMs) focussing on the shoulder, assessing "activity limitations." STUDY DESIGN: Systematic review. The study population had to consist of patients with shoulder pain. We excluded postoperative patients or patients with generic diseases. The methodological quality of the selected studies and the results of the measurement properties were critically appraised and rated using the COSMIN checklist. RESULTS: Out of a total of 3427 unique hits, 31 articles, evaluating 7 different questionnaires, were included. The SPADI is the most frequently evaluated PROM and its measurement properties seem adequate apart from a lack of information regarding its measurement error and content validity. CONCLUSION: For English, Norwegian and Turkish users, we recommend to use the SPADI. Dutch users could use either the SDQ or the SST. In German, we recommend the DASH. In Tamil, Slovene, Spanish and the Danish languages, the evaluated PROMs were not yet of acceptable validity. None of these PROMs showed strong positive evidence for all measurement properties. We propose to develop a new shoulder PROM focused on activity limitations, taking new knowledge and techniques into account.
Assuntos
Atividades Cotidianas , Medição da Dor , Medidas de Resultados Relatados pelo Paciente , Dor de Ombro/fisiopatologia , Adulto , Lista de Checagem , Feminino , Humanos , Idioma , MEDLINE , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Reprodutibilidade dos Testes , Ombro/fisiopatologia , Inquéritos e QuestionáriosRESUMO
BACKGROUND: 'Chemsex' is a colloquial term used in the UK that describes sex under the influence of psychoactive substances (typically crystal methamphetamine, mephedrone and gamma-hydroxybutyric acid (GHB)/gamma-butyrolactone (GBL)). Recently, concern has been raised as to the impact of such behaviour on HIV/sexually transmitted infection (STI) transmission risk behaviour, which this qualitative study aimed to explore via semistructured interviews with gay men living in three South London boroughs. METHODS: Interviews were conducted with 30 community-recruited gay men (age range 21-53) who lived in the boroughs of Lambeth, Southwark and Lewisham, and who had used crystal methamphetamine, mephedrone or GHB/GBL either immediately before or during sex with another man during the previous 12â months. Data were subjected to a thematic analysis. RESULTS: Chemsex typically featured more partners and a longer duration than other forms of sex, and the relationship between drug use and HIV/STI transmission risk behaviour was varied. While some men believed that engaging in chemsex had unwittingly led them to take risks, others maintained strict personal rules about having safer sex. Among many participants with diagnosed HIV, there was little evidence that the use of drugs had significantly influenced their engagement in condomless anal intercourse (primarily with other men believed to be HIV positive), but their use had facilitated sex with more men and for longer. CONCLUSIONS: Analysis revealed that, within this sample, chemsex is never less risky than sex without drugs, and is sometimes more so. Targeted clinic-based and community-based harm reduction and sexual health interventions are required to address the prevention needs of gay men combining psychoactive substances with sex.
Assuntos
Transtornos Relacionados ao Uso de Anfetaminas/psicologia , Homossexualidade Masculina/estatística & dados numéricos , Drogas Ilícitas/efeitos adversos , Comportamento Sexual/efeitos dos fármacos , Parceiros Sexuais/psicologia , Infecções Sexualmente Transmissíveis/psicologia , Sexo sem Proteção/psicologia , Adulto , Transtornos Relacionados ao Uso de Anfetaminas/epidemiologia , Redução do Dano , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Entrevistas como Assunto , Londres/epidemiologia , Masculino , Metanfetamina/efeitos adversos , Pessoa de Meia-Idade , Pesquisa Qualitativa , Assunção de Riscos , Infecções Sexualmente Transmissíveis/prevenção & controle , Infecções Sexualmente Transmissíveis/transmissãoRESUMO
BACKGROUND: Gay and bisexual men (GBM) have higher substance use prevalences than general population samples - often attributed to stigmatisation of sexual minority identities. We examined how influential public health research on substance use among GBM interprets this behaviour and what GBM-specific identities emerge through the discourses employed. METHODS: We searched Web of Science for publications on substance use among GBM, selecting 60 of the most cited papers published during 2000-2020. We studied the language used to describe and interpret drug-using behaviour using critical discourse analysis, focusing on interpretive repertoires and subject positions. RESULTS: Three distinct discursive tendencies were identified. First, in constructing a target population, GBM who use illicit drugs are positioned as deficient, socially irresponsible, and maladapted to dealing with stigmatisation and HIV risks. Second, in shifting the focus beyond the individual, the gay community is conceptualised as offering a safe space for socialisation. Nonetheless, gay community spaces are problematised as promoting substance use among vulnerable GBM through aggravating loneliness and normalising drug use as a form of maladaptive (avoidance) coping. Third, counterdiscursive movements add nuance, context, and comparisons that relativise rather than generalise substance use and focus on pleasure and self-determination. Such discourses centre the need for interventions that disrupt homophobic socio-structures instead of individualising approaches to limit non-conformity. CONCLUSION: 'Expert' assessments of substance use among GBM perpetuate pathologising understandings of this behaviour and promote abject subject positions, contributing to perpetuations of intergroup stigma and social exclusion based on drug and sexual practices. Our findings highlight the need for deliberate and critical engagement with prior research and a conscious effort to disrupt dominant discourses on GBM's substance use.
Assuntos
Drogas Ilícitas , Minorias Sexuais e de Gênero , Transtornos Relacionados ao Uso de Substâncias , Bissexualidade , Homossexualidade Masculina , Humanos , Masculino , Saúde Pública , Comportamento Sexual , Transtornos Relacionados ao Uso de Substâncias/epidemiologiaRESUMO
The Malaysian government has committed to 'Fast Tracking the HIV Response' to achieve UNAIDS 2030 targets to end AIDS. The epidemic is concentrated among key populations and has shifted from people who inject drugs to HIV infection through sexual transmission among men who have sex with men, sex workers and transgender people. The aim of this scoping review was to examine social and behavioural research published since 2005 that can inform understanding of each stage of the 90:90:90 treatment cascade (as proposed by UNAIDS), including HIV risk behaviours and testing practices that precede entry. We found a concentration of studies related to predictors or correlates of HIV infections (mostly among men who have sex with men) and a shortfall in literature pertaining to sex workers or transgender people. While several studies examined factors associated with HIV testing, only one examined uptake of antiretroviral therapy and two explored issues of treatment adherence. No study examined broader care and support of people living with HIV. To scale-up effective programmes and apprise investment to achieve the ambitious targets set-out in the Malaysian National HIV/AIDS Strategic Plan, a combination of comprehensive strategic information and evidence generated through primary research is critical.
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Infecções por HIV , Profissionais do Sexo , Minorias Sexuais e de Gênero , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Malásia/epidemiologia , MasculinoRESUMO
BACKGROUND: While illicit drug use is prevalent among gay and bisexual men (GBM) in Australia, little is known about the factors associated with injecting drug use among GBM. METHODS: The Following Lives Undergoing Change (FLUX) study is a national, online prospective observational cohort investigating drug use among Australian GBM. Eligible participants were men living in Australia who were aged 16.5 years or older, identified as gay or bisexual or had sex with at least one man in the last year. We examined baseline data for associations between socio-demographic and behavioural characteristics and recent (last six months) injecting using log-binomial regression. RESULTS: Of 1995 eligible respondents, 206 (10.3%) reported ever injecting drugs and 93 (4.7%) had injected recently, most commonly crystal (91.4%) and speed (9.7%). Among recent injectors, only 16 (17.2%) reported injecting at least weekly; eight (8.6%) reported recent receptive syringe sharing. Self-reported HIV and HCV prevalence was higher among recent injectors than among other participants (HIV: 46.2% vs 5.0%, pâ¯<â¯.001; HCV: 16.1% vs. 1.2%, pâ¯<â¯.001). Recent injecting was associated with lifetime use of more drug classes (adjusted prevalence ratio (APR)â¯=â¯1.31, 95% Confidence Interval (95%CI) 1.21-1.41), longer time since initiating party drug use (APRâ¯=â¯1.02, 95%CI 1.01-1.04), greater numbers of sex partners (2-10 sex partners: APRâ¯=â¯3.44, 95%CI 1.45-8.20; >10 sex partners: APRâ¯=â¯3.21, 95%CI 1.30-7.92), group sex (APRâ¯=â¯1.42, 95%CI 1.05-1.91) and condomless anal intercourse with casual partners (APRâ¯=â¯1.81, 95%CI 1.34-2.43) in the last six months. CONCLUSIONS: Observed associations between injecting and sexual risk reflect a strong relationship between these practices among GBM. The intersectionality between injecting drug use and sex partying indicates a need to integrate harm reduction interventions for GBM who inject drugs into sexual health services and targeted sexual health interventions into Needle and Syringe Programs.
Assuntos
Minorias Sexuais e de Gênero/psicologia , Minorias Sexuais e de Gênero/estatística & dados numéricos , Abuso de Substâncias por Via Intravenosa/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adolescente , Adulto , Austrália/epidemiologia , Humanos , Masculino , Prevalência , Estudos Prospectivos , Fatores de Risco , Adulto JovemRESUMO
Process-based population models need sound and comprehensive data on an animal's response to climatic factors if they are to function reliably under a wide range of climatic conditions. To this end, different aged egg masses of the livestock tick, Rhipicephalus (Boophilus) microplus, were either desiccated in atmospheres with saturation deficits of 5, 10, 15 or 20 mmHg at 20 or 26 degrees C, or chilled at temperatures of 5, 10 or 14 degrees C with a saturation deficit of 1 mmHg for varying periods. The survival rate of the eggs through to hatching was related to the initial age of the eggs, the severity of the treatments and the duration of exposure. We established a relationship between desiccation and weight loss of eggs and, secondarily between weight loss and mortality. Mortality increased with weight loss until it reached 100% when the weight loss was about 35%. Low temperatures were increasingly detrimental to eggs as they reduced from 14 to 5 degrees C. Freshly laid eggs were more susceptible to both low temperatures and desiccation than were older eggs. Larvae emerging from eggs that were stressed by either cold or desiccation lived for a shorter time under optimal conditions than did larvae from eggs incubated under optimal conditions. Larvae from eggs with the same hatching rate had the same viability, whether the stress was induced by desiccation or low temperatures. Models were developed to describe the dynamics of weight loss of eggs with desiccation, the accumulation of cold stress of the eggs, and their effects on egg survival and larval viability. These data provide a sound basis for the development of predictive models for use under field conditions, although the response of different aged eggs to low temperatures was too variable to allow us to develop an accurate model to describe that relationship. Field models will also need to take diurnal temperature fluctuations into account.
Assuntos
Clima , Rhipicephalus/fisiologia , Estações do Ano , Animais , Morte , Dessecação , Ovos , Larva , Modelos Biológicos , Controle Biológico de Vetores , TemperaturaRESUMO
ABSTRACT Objective: Screening for childhood obesity is a necessary step in developing appropriate and effective interventions. We evaluated the diagnostic performance of various recommended international anthropometric cut-offs based on body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), triceps skinfold (TSF), and mid-upper arm circumference (MUAC) in predicting excess adiposity (body fat ≥ 25%) in a random sample of Trinidadian preschoolers. Methods: After obtaining written parental consent, weight, height, WC, TSF, and MUAC were measured in 596 children using standard procedures. These were used to calculate BMI for age, WHtR, TSF-for-age z-scores, and MUAC-for-age z-scores. Percentage body fat was measured using a Tanita-531 foot-to-foot bioelectrical impedance analyser (BIA). Sensitivities, specificities and area under the receiver-operating curve analysis and predictive values were then computed in reference to BIA estimates. Results: The prevalence of excess adiposity was 12.2% and 5.1% among males and females, respectively. Sensitivities for the various cut-offs ranged from 20.0% to 75.0% and 57.1% to 96.9% among males and females, respectively. WHO-BMI recommended cut-offs and those based on MUAC z-scores had significantly higher sensitivities in females than in males. TSF z-scores had significantly lower sensitivities compared to those based on BMI and WHtR among males. Similarly, specificities ranged from 81.3% to 99.9% and 79.8% to 99.9% among males and females, respectively. In girls, cut-offs based on TSF z-scores had a higher likelihood ratio than cut-offs from Centers for Disease Control, International Obesity Task Force and WHtR. Diagnostic performance was not associated with ethnicity. Conclusion: Our results suggest that diagnostic performance was associated with gender and the cut-offs used; however, it was not associated with ethnicity.
Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Obesidade Infantil/diagnóstico , Dobras Cutâneas , Trinidad e Tobago/epidemiologia , Circunferência Braquial , Índice de Massa Corporal , Estudos Transversais , Circunferência da Cintura , Obesidade Infantil/epidemiologia , Razão Cintura-EstaturaRESUMO
Widespread ash dispersal poses a significant natural hazard to society, particularly in relation to disruption to aviation. Assessing the extent of the threat of far-travelled ash clouds on flight paths is substantially hindered by an incomplete volcanic history and an underestimation of the potential reach of distant eruptive centres. The risk of extensive ash clouds to aviation is thus poorly quantified. New evidence is presented of explosive Late Pleistocene eruptions in the Pacific Arc, currently undocumented in the proximal geological record, which dispersed ash up to 8000 km from source. Twelve microscopic ash deposits or cryptotephra, invisible to the naked eye, discovered within Greenland ice-cores, and ranging in age between 11.1 and 83.7 ka b2k, are compositionally matched to northern Pacific Arc sources including Japan, Kamchatka, Cascades and Alaska. Only two cryptotephra deposits are correlated to known high-magnitude eruptions (Towada-H, Japan, ca 15 ka BP and Mount St Helens Set M, ca 28 ka BP). For the remaining 10 deposits, there is no evidence of age- and compositionally-equivalent eruptive events in regional volcanic stratigraphies. This highlights the inherent problem of under-reporting eruptions and the dangers of underestimating the long-term risk of widespread ash dispersal for trans-Pacific and trans-Atlantic flight routes.
RESUMO
The presence and cellular localization of five membrane peptidases has been investigated in peripheral nerves, including those of the autonomic nervous system, in the pig. Endopeptidase-24.11 ("enkephalinase") peptidyl dipeptidase A, aminopeptidase N, aminopeptidase W and dipeptidyl peptidase IV were studied by both enzymic assays of membranes prepared from samples of nerve and by immunoperoxidase histochemistry at light and in two cases, endopeptidase-24.11 and aminopeptidase W, at electron microscopic levels. All five peptidases could be quantified by enzymic assay, though the activities were about 1% of those in renal microvilli and less than those of choroid plexus membranes. Endopeptidase-24.11 was associated with Schwann cell membranes in all types of nerve examined, including major nerves containing predominantly myelinated fibres as well as autonomic nerves, such as the vagus and splenic nerves and the sympathetic chain, staining being observed in membranes associated with myelinated and unmyelinated fibres. The Schwann cell location of endopeptidase-24.11 was confirmed by correlation with immunostaining for glial fibrillary acidic protein and by electron microscopy. This peptidase is known to have a wide repertoire of susceptible substrates among neuropeptides which was here shown to include vasoactive intestinal polypeptide (Km 268 microM, kcat 568 min-1), one of a number of neuropeptides present in peripheral nerve fibres. Three of the peptidases, peptidyl dipeptidase A, aminopeptidase N and dipeptidyl peptidase IV, were associated with microvessels of peripheral nerves. Aminopeptidase N was also observed in connective tissue elements, including the perineurium. Aminopeptidase W was unique among the five peptidases in having a neuronal localization. This was observed in unmyelinated and myelinated nerves and was supported by comparison with the pattern of staining observed for neurofilament protein and by electron microscopic immunoperoxidase staining. This observation was unexpected since aminopeptidase W has not been detected as a neuronal marker in the brain. Some possible roles for the membrane peptidases in peripheral nerves are discussed.
Assuntos
Proteínas de Membrana/análise , Proteínas do Tecido Nervoso/análise , Peptídeo Hidrolases/análise , Nervos Periféricos/enzimologia , Suínos/metabolismo , Animais , Plexo Braquial/enzimologia , Exopeptidases , Nervo Femoral/enzimologia , Imunofluorescência , Técnicas Imunoenzimáticas , Microscopia Eletrônica , Microscopia Imunoeletrônica , Neuropeptídeos/metabolismo , Nervos Periféricos/ultraestruturaRESUMO
The free-living stages of the tick Haemaphysalis (Kaiseriana) longicornis were studied at Mt Tamborine (526 m altitude) and Amberley (25 m altitude) in southeast Queensland between 1971 and 1980. Data are presented on the number of eggs and larvae produced, the moulting success of engorged larvae and nymphs and the survival and behaviour of unfed larvae, nymphs and adult females. Temperature, moisture, daylength, grass length and age of unfed ticks were investigated as sources of variation in development rates, fecundity or survival. At Mt Tamborine the life cycle was well synchronized with the seasons to produce one generation per year. At Amberley higher temperatures accelerated development rates and would have delayed diapause, so disrupting the life cycle.
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Carrapatos/fisiologia , Animais , Comportamento Alimentar , Feminino , Fertilidade , Larva/fisiologia , Ninfa/fisiologia , Oviposição , Queensland , Carrapatos/crescimento & desenvolvimentoRESUMO
This study was undertaken to examine how eight putative adhesive agents bound to plastic surfaces affected the capacity of bovine erythrocytes, infected with either virulent or avirulent strains of Babesia bovis, to adhere in vitro. Thrombospondin (TSP) induced B. bovis-infected bovine erythrocytes to adhere and adherence was augmented when the infected blood was cultured for 24 h before the assay. Moreover, TSP also caused erythrocytes infected with avirulent strains of B. bovis to adhere to plastic in vitro. Laminin promoted the adherence of infected, and to a lesser extent, of uninfected erythrocytes.
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Babesia/fisiologia , Plaquetas/metabolismo , Eritrócitos/parasitologia , Laminina/metabolismo , Glicoproteínas de Membrana/metabolismo , Animais , Bovinos , Adesão Celular , Eritrócitos/metabolismo , TrombospondinasRESUMO
In order to elucidate the pathogenesis of vasculitis in muscle and nerve a clinicopathological study was performed in 23 patients. The patients could be classified into three groups: I multisystem vasculitis (n = 4); II multisystem disease with vasculitis detectable in nerve, muscle, or both (n = 11); and III localised disease with vasculitis in nerve, muscle, or both (n = 8). Ten of 23 patients had vasculitis in both muscle and nerve biopsies; 6 from groups I and II, and 4 from group III indicating that vasculitis confined to muscle and nerve represents a distinct clinicopathological entity. The neuromuscular manifestations in the 23 patients were sensori-motor polyneuropathy (n = 9), mononeuritis multiplex (n = 6), mononeuropathy (n = 3), proximal myopathy (n = 4), and muscle tenderness without weakness (n = 1). Sensori-motor polyneuropathy was found in 8/11 patients from group II, and mononeuritis multiplex in 5/8 patients from group III. Immunotypic analysis, and immunofluorescence patterns indicate that the pathogenesis of vasculitis in muscle and nerve is heterogeneous and suggest that cell mediated and immune complex mechanisms predominate and may be operative in all three patient groups, with an antibody-mediated humoral mechanism in some patients with paraproteinaemic states (group II).
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Doenças Musculares/patologia , Doenças Neuromusculares/patologia , Doenças do Sistema Nervoso Periférico/patologia , Vasculite/patologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Biópsia , Humanos , Doenças do Complexo Imune/complicações , Doenças do Complexo Imune/imunologia , Imunidade Celular , Subpopulações de Linfócitos , Doenças Musculares/etiologia , Doenças Musculares/imunologia , Doenças Neuromusculares/etiologia , Doenças Neuromusculares/imunologia , Paraproteinemias/complicações , Paraproteinemias/imunologia , Doenças do Sistema Nervoso Periférico/etiologia , Doenças do Sistema Nervoso Periférico/imunologia , Vasculite/etiologia , Vasculite/imunologiaRESUMO
Female rats were fed from weaning on diets with sucrose, starch, glucose or fructose as the carbohydrate source. Animals were killed at various stages throughout pregnancy and early lactation. Maternal plasma triglycerides (TG), cholesterol, free fatty acids, glucose, insulin and corticosteroids were measured. Lipogenic activity was assayed in the livers, adipose tissue and mammary tissue, and the results compared with those from non-pregnant rats. Insulin, corticosteroids and hepatic lipogenesis were also assayed in the embryos and in newborn pups. Dietary sucrose and fructose produced a significantly higher concentration of plasma TG in the non-pregnant, pregnant and lactating rats than did starch and glucose. All the diets led to an increase in TG concentration at the 20th day of pregnancy, which returned to the original concentration 2 days post-partum. The hypertriglyceridaemia of late pregnancy was accentuated by the feeding of sucrose and fructose. Maternal concentrations of plasma glucose were significantly reduced towards the end of pregnancy in all dietary groups. The replacement of starch by sucrose, or of glucose by fructose, enhanced hepatic lipogenesis. Fructose but not sucrose depressed fat synthesis in the adipose tissue. Hepatic fatty acid synthetase activity was increased in late pregnancy on all diets except that with starch. Late pregnancy intensified hepatic lipogenesis in rats fed sucrose or fructose. The results are discussed in relation to the metabolic changes during pregnancy and to sucrose feeding.
Assuntos
Carboidratos da Dieta , Lactação , Metabolismo dos Lipídeos , Gravidez , Tecido Adiposo/enzimologia , Tecido Adiposo/metabolismo , Corticosteroides/sangue , Animais , Glicemia/análise , Colesterol/sangue , Ácido Graxo Sintases/metabolismo , Ácidos Graxos não Esterificados/sangue , Feminino , Frutose , Glucose , Glucosefosfato Desidrogenase/metabolismo , Insulina/sangue , Fígado/enzimologia , Fígado/metabolismo , Glândulas Mamárias Animais/metabolismo , Ratos , Amido , Sacarose , Fatores de Tempo , Triglicerídeos/sangueRESUMO
Alexander's disease is a progressive degenerative neurological disorder developing in early childhood which is characterized by accumulation of Rosenthal fibres throughout the cerebral white matter. These fibres are composed of glial fibrillary acidic protein and ubiquinated alpha beta crystallin. The absence of atypia, increased cellularity, mitotic activity or necrosis in biopsy material allows differentiation from neoplasia glial processes. Clinical features suggestive of the diagnosis include progressive mental retardation with an increase in head circumference.