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1.
J Gen Virol ; 105(5)2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38767608

RESUMEN

Herpesviruses establish a well-adapted balance with their host's immune system. Despite this co-evolutionary balance, infections can lead to severe disease including neurological disorders in their natural host. In horses, equine herpesvirus 1 (EHV-1) causes respiratory disease, abortions, neonatal foal death and myeloencephalopathy (EHM) in ~10 % of acute infections worldwide. Many aspects of EHM pathogenesis and protection from EHM are still poorly understood. However, it has been shown that the incidence of EHM increases to >70 % in female horses >20 years of age. In this study we used old mares as an experimental equine EHV-1 model of EHM to identify host-specific factors contributing to EHM. Following experimental infection with the neuropathogenic strain EHV-1 Ab4, old mares and yearling horses were studied for 21 days post-infection. Nasal viral shedding and cell-associated viremia were assessed by quantitative PCR. Cytokine/chemokine responses were evaluated in nasal secretions and cerebrospinal fluid (CSF) by Luminex assay and in whole blood by quantitative real-time PCR. EHV-1-specific IgG sub-isotype responses were measured by ELISA. All young horses developed respiratory disease and a bi-phasic fever post-infection, but only 1/9 horses exhibited ataxia. In contrast, respiratory disease was absent in old mares, but all old mares developed EHM that resulted in euthanasia in 6/9 old mares. Old mares also presented significantly decreased nasal viral shedding but higher viremia coinciding with a single fever peak at the onset of viremia. According to clinical disease manifestation, horses were sorted into an EHM group (nine old horses and one young horse) and a non-EHM group (eight young horses) for assessment of host immune responses. Non-EHM horses showed an early upregulation of IFN-α (nasal secretions), IRF7/IRF9, IL-1ß, CXCL10 and TBET (blood) in addition to an IFN-γ upregulation during viremia (blood). In contrast, IFN-α levels in nasal secretions of EHM horses were low and peak levels of IRF7, IRF9, CXCL10 and TGF-ß (blood) coincided with viremia. Moreover, EHM horses showed significantly higher IL-10 levels in nasal secretions, peripheral blood mononuclear cells and CSF and higher serum IgG3/5 antibody titres compared to non-EHM horses. These results suggest that protection from EHM depends on timely induction of type 1 IFN and upregulation cytokines and chemokines that are representative of cellular immunity. In contrast, induction of regulatory or TH-2 type immunity appeared to correlate with an increased risk for EHM. It is likely that future vaccine development for protection from EHM must target shifting this 'at-risk' immunophenotype.


Asunto(s)
Citocinas , Infecciones por Herpesviridae , Herpesvirus Équido 1 , Enfermedades de los Caballos , Animales , Caballos , Herpesvirus Équido 1/inmunología , Femenino , Enfermedades de los Caballos/virología , Enfermedades de los Caballos/inmunología , Infecciones por Herpesviridae/veterinaria , Infecciones por Herpesviridae/inmunología , Infecciones por Herpesviridae/virología , Citocinas/sangre , Citocinas/inmunología , Anticuerpos Antivirales/sangre , Esparcimiento de Virus , Viremia/inmunología , Viremia/veterinaria , Inmunoglobulina G/sangre
2.
Eur J Clin Microbiol Infect Dis ; 33(12): 2259-66, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25022447

RESUMEN

The diagnostic yield of pulmonary tuberculosis (TB) by sputum induction (SI) at the first point of contact with health services, conducted in all patients with suspected TB regardless of the ability to expectorate spontaneously, has not been evaluated. We compared the diagnostic yield of SI to routine sputum collection in a South African community setting. Ambulatory patients with suspected TB provided a 'spot' expectorated sputum sample, an SI sample by hypertonic (5 %) saline nebulization, and early morning expectorated sputum sample. The diagnostic yield of sputum smear microscopy and liquid culture (denominator all subjects with any positive Mycobacterium tuberculosis culture), and time-to-positivity of culture were compared between SI and expectorated samples. A total of 555 subjects completed the SI procedure, of whom 132 (24 %) were human immunodeficiency virus (HIV)-infected. One hundred and twenty-nine samples (129, 23 %) were M. tuberculosis culture-positive. The time-to-positivity of Mycobacteria Growth Indicator Tube (MGIT) culture was shorter for SI (median difference 2 days, p = 0.63) and for early morning expectorated sputum (median difference 2 days, p = 0.02) compared to spot expectorated sputum. However, there was no difference in the culture-positive diagnostic yield between SI and spot expectorated sputum [difference +0.7 %; confidence interval (CI) -7.0 to +8.5 %, p = 0.82] or SI and early morning expectorated sputum (difference +4.7 %; CI -3.2 to +12.5 %, p = 0.20) for all subjects or for HIV-infected subjects. SI reduces the time to positive M. tuberculosis culture, but does not increase the rate of positive culture compared to routine expectorated sputum collection. SI cannot be recommended as the routine collection method at first contact among ambulatory patients with suspected TB in high-burden communities.


Asunto(s)
Mycobacterium tuberculosis/aislamiento & purificación , Manejo de Especímenes/métodos , Esputo/microbiología , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/microbiología , Adulto , Técnicas Bacteriológicas , Femenino , Infecciones por VIH/microbiología , Humanos , Masculino , Sudáfrica , Manejo de Especímenes/efectos adversos , Tuberculosis Pulmonar/virología
3.
Eur J Clin Microbiol Infect Dis ; 31(7): 1619-30, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22095153

RESUMEN

Sputum induction (SI) has been proposed as the optimal sample collection method for patients with paucibacillary tuberculosis (TB). Studies reporting the culture of Mycobacterium tuberculosis from SI were reviewed. A random-effects meta-analysis of diagnostic yield (numerator M. tuberculosis SI culture-positive cases; denominator all culture-positive cases) was conducted. Diagnostic yields (95% confidence intervals, CIs) were displayed as Forest plots. Heterogeneity was evaluated using Chi-squared and I-squared tests and meta-regression analysis. Ninety publications were screened, 28 full-text papers reviewed, and 17 analyzed. Collectively, n=627 SI culture-positive cases among n=975 culture-confirmed TB cases were reported. The diagnostic yield of SI ranged from 35 to 95%. The pooled diagnostic yield was 74% (CI 65-81%), with significant heterogeneity (p<0.0001, I2=86%). There were no statistically significant differences in the yield between sub-groups defined by human immunodeficiency virus (HIV) prevalence or age. Univariate analysis demonstrated that the use of fiberoptic bronchoscopy (FOB) as the comparator method was associated with a 22% reduction (CI 2-42%) in the diagnostic yield of SI. However, after adjustment for confounding, the meta-regression analysis showed that FOB usage (p=0.21) and saline concentration (p=0.31) were not independently associated with the diagnostic yield. SI will detect approximately three-quarters of M. tuberculosis culture-positive cases under study conditions. Significant heterogeneity in the diagnostic yield was not explained by HIV prevalence, age, or the use of FOB as the comparator method. The use of a particular nebulized saline concentration for SI cannot be recommended on the basis of this meta-regression analysis.


Asunto(s)
Técnicas Bacteriológicas/métodos , Mycobacterium tuberculosis/aislamiento & purificación , Esputo/microbiología , Tuberculosis Pulmonar/diagnóstico , Humanos , Sensibilidad y Especificidad
4.
Eur J Clin Microbiol Infect Dis ; 31(4): 529-37, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21796347

RESUMEN

Sputum induction by the inhalation of hypertonic saline may increase the yield of microbiological diagnosis of pulmonary tuberculosis (TB). This is particularly relevant in paucibacillary TB, such as in children or human immunodeficiency virus (HIV)-infected patients. Sputum induction must be shown to be safe and tolerable in community settings where invasive diagnostic methods are unavailable. The objective of this study was to describe the changes in physiological parameters and adverse events occurring during sputum induction in ambulatory adult and adolescent TB suspects recruited in community clinics. Sputum induction was performed in HIV-infected (n = 35) and HIV-uninfected (n = 67) TB suspects (n = 102). Oxygen saturation (%), blood pressure (mm Hg), heart rate (/minute), respiratory rate (/minute), and adverse events were monitored at baseline, continuously during the salbutamol pre-treatment and saline nebulization phases, and for 30 min afterwards. During nebulization, there was a statistically significant increase in oxygen saturation (1%, p < 0.0001), systolic BP (7 mm Hg, p < 0.0001), and diastolic BP (2 mm Hg, p = 0.008). Post-nebulization decrease in the systolic BP occurred (4 mm Hg, p = 0.016). These changes were not considered to be clinically significant. Eight minor, transitory, self-resolving adverse events occurred (labored breathing, n = 2; chest pain, n = 2; paroxysmal coughing, n = 1; elevated heart rate, n = 1; vomiting, n = 1; hypotension, n = 1), leading to procedure termination in four participants. No serious adverse events occurred. Induced sputum is safe, tolerable, and feasible in adult and adolescent TB suspects in a community healthcare setting.


Asunto(s)
Solución Salina Hipertónica/administración & dosificación , Solución Salina Hipertónica/efectos adversos , Esputo/microbiología , Tuberculosis Pulmonar/diagnóstico , Administración por Inhalación , Adolescente , Adulto , Niño , Femenino , Infecciones por VIH/complicaciones , Humanos , Masculino , Adulto Joven
5.
S Afr Med J ; 111(7): 649-654, 2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-34382548

RESUMEN

BACKGROUND: Research in human vaccines and immunisation plays a crucial role in shaping national, regional and global health policies aimed at controlling vaccine preventable diseases (VPDs). To our knowledge, the landscape of human vaccine and immunisation research in South Africa (SA) is not well characterised. OBJECTIVES: To characterise research in human vaccines and immunisation in SA. METHODS: We conducted a bibliometric study. Seven electronic databases (PubMed; Scopus; Web of Science; Cochrane; CINAHL; Africa-Wide Information; and MEDLINE (via EBSCOhost)) were searched for eligible studies published in English between 1 January 2007 and 31 March 2020. Selected primary studies needed to be on human vaccine and immunisation research conducted in SA. All types of reviews were excluded. For the included studies, outcomes of interest included publication journals, publication trends, types of studies and VPDs, targeted populations, as well as author affiliations. RESULTS: A total of 9 212 studies was retrieved. After screening for eligibility, 366 studies met the inclusion criteria. The key findings were as follows: (i) a total of 54 (14.8 %) articles on human vaccine and immunisation research in SA appeared in local journals, while 312 (85.2%) were in non-SA (international) journals; (ii) the number of publications on human vaccine and immunisation research in SA increased from 13 in 2007 to 47 in 2015; (iii) there were 189 (51.7%) operational studies and 177 (48.3%) clinical studies, with 88 (49.7%) of the latter being clinical trials; (iv) human vaccine and immunisation research in SA is conducted across all age groups, with a focus on children; and (v) authors of the identified research outputs and those mostly represented were from the universities of Cape Town and the Witwatersrand, Johannesburg. CONCLUSIONS: The landscape of human vaccine and immunisation research in SA is growing and adapting to the emerging trends in vaccinology, with a focus on the duo epidemic of HIV and TB, as well as Expanded Programme on Immunisation (EPI)-related vaccinations. This research contributes to locally relevant evidence that can be used to inform future vaccine and EPI-related research.


Asunto(s)
Bibliometría , Investigación Biomédica/estadística & datos numéricos , Inmunización , Vacunas/uso terapéutico , Control de Enfermedades Transmisibles , Humanos , Sudáfrica
6.
Genes Immun ; 11(7): 561-72, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20445564

RESUMEN

Toll-like receptors (TLRs) are critical mediators of the immune response to pathogens. The influence of human TLR6 polymorphisms on susceptibility to infection is only partially understood. Most microbes contain lipopeptides recognized by TLR2/1 or TLR2/6 heterodimers. Our aim was to determine whether single nucleotide polymorphisms in TLR6 are associated with altered immune responses to lipopeptides and whole mycobacteria. We sequenced the TLR6 coding region in 100 healthy South African adults to assess genetic variation and determined associations between polymorphisms and lipopeptide- and mycobacteria-induced interleukin (IL)-6 production in whole blood. We found two polymorphisms, C745T and G1083C, that were associated with altered IL-6 secretion. G1083C was associated with altered IL-6 levels in response to lipopeptides, Mycobacterium tuberculosis lysate (Mtb lysate, P=0.018) and Bacille Calmette-Guerin (BCG P=0.039). The 745T allele was also associated with lower NF-κB signaling in response to di-acylated lipopeptide, PAM2 (P=0.019) or Mtb (P=0.026) in an HEK293 cell line reconstitution assay, compared with the 745C allele. We conclude that TLR6 polymorphisms may be associated with altered lipopeptide-induced cytokine responses and recognition of Mtb. These studies provide new insight into the role of TLR6 variation and the innate immune response to human infection.


Asunto(s)
Interleucina-6/metabolismo , Mycobacterium , Polimorfismo de Nucleótido Simple , Receptor Toll-Like 6/genética , Adulto , Citocinas/genética , Células HEK293 , Humanos , Factores Inmunológicos/genética , Lipopéptidos/metabolismo , Mycobacterium bovis/genética , Mycobacterium bovis/metabolismo , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/inmunología , Mycobacterium tuberculosis/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Transducción de Señal/genética , Transducción de Señal/inmunología , Receptores Toll-Like/metabolismo
7.
Acta Paediatr ; 99(5): 705-710, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20146723

RESUMEN

AIM: Little is known about pyridoxine nutriture of children treated with isoniazid (INH) regimens. This study documents plasma pyridoxal 5'-phosphate (PLP) concentrations in children, HIV-infected and HIV-uninfected, receiving INH regimens. METHODS: Children from the Western Cape of South Africa hospitalized for tuberculosis (TB) management were studied. Plasma PLP concentrations were determined on enrolment, 1-month after commencing TB treatment, and again after 4-month's treatment. The children received a supplement meeting pyridoxine requirements. RESULTS: Nineteen HIV-infected and 33 HIV-uninfected children received INH (dosage range 4-20 mg/kg) daily. Mean PLP plasma concentrations on enrolment were 8.32 (SD 6.75) ng/mL and 11.28 (SD 3.02) ng/mL in HIV-infected and HIV-uninfected children, respectively (p = 0.11) and after 4-month's treatment 6.75 (SD 2.71) ng/mL and 14.76 (SD 7.96) ng/mL (p < 0.001). On enrolment 9 (50%) HIV-infected and 5 (15%) HIV-uninfected children (p = 0.016) had suboptimal PLP concentrations (<6 ng/mL); after 4-month's treatment 8 (42%) and 2 (6%) (p = 0.004). CONCLUSION: Plasma PLP concentrations in children treated for TB were low on enrolment in HIV-infected and HIV-uninfected children; after 4-month's treatment low values were still common in HIV-infected children. Additional pyridoxine supplementation of malnourished children treated for tuberculosis is advisable, particularly those HIV-infected.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Antituberculosos/uso terapéutico , Isoniazida/uso terapéutico , Fosfato de Piridoxal/sangre , Tuberculosis/tratamiento farmacológico , Infecciones Oportunistas Relacionadas con el SIDA/sangre , Adolescente , Niño , Preescolar , Femenino , Genotipo , Infecciones por VIH/complicaciones , Humanos , Lactante , Masculino , Sudáfrica , Tuberculosis/sangre , Tuberculosis/complicaciones
8.
S Afr Med J ; 110(6): 525-531, 2020 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-32880566

RESUMEN

BACKGROUND: Infection with human papillomavirus (HPV) significantly increases the risk of developing cervical cancer later in life. Therefore, globally, HPV vaccines targeted to pre-adolescent and adolescent girls have been on the rise since the licensure in 2006. However, the introduction of HPV vaccines has been relatively slow in Africa. At the end of 2016, only 8 of the 54 countries in Africa were reported to have introduced HPV vaccination at a national level. By 2019, the number of countries had grown marginally to 11. OBJECTIVES: To investigate stakeholders' perspectives on the experiences, challenges and lessons learnt during national HPV vaccine introduction in Africa. METHODS: A questionnaire was administered to selected participants from 8 African countries. These countries had successfully introduced HPV vaccination at a national level by the end of 2016. We used in-depth interviews and self-administered online questionnaires for data collection and analysis. Data are presented without naming the country or participants; therefore, readers will not be able to identify the results that are specific to individual countries. Narrative and thematic reporting were used to describe the results. RESULTS: We obtained results from 6 of the 8 targeted countries. The challenges reported during HPV vaccination programmes were: identifying the target population, using a school-based vaccine-delivery strategy, obtaining political support, the need to integrate HPV vaccination with existing school health programmes and engaging multiple stakeholders. These challenges were similar in all 6 countries. The lessons learnt were that a school-based delivery strategy is a successful approach for national HPV vaccination, and that identifying girls for vaccination at schools was less challenging if implemented through a class-based instead of an age-based approach. CONCLUSIONS: Most African countries do not have established platforms to deliver vaccines to pre-adolescent and adolescent populations. The successful introduction of the HPV vaccine through school-based vaccination strategies in African countries may have created a platform to deliver other adolescent vaccines. The similarity of the study findings across the 6 participating countries further strengthens the need to document and disseminate the challenges and lessons learnt during HPV vaccine introduction in Africa. Documentation and dissemination of the challenges and lessons learnt are useful to other countries in Africa that plan to introduce an HPV vaccination programme, and possibly other adolescent vaccines.


Asunto(s)
Programas de Inmunización/organización & administración , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/administración & dosificación , Servicios de Salud Escolar , Neoplasias del Cuello Uterino/prevención & control , Adolescente , África , Niño , Femenino , Humanos , Encuestas y Cuestionarios
9.
Eur J Vasc Endovasc Surg ; 38(6): 748-9, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19666232

RESUMEN

INTRODUCTION: A national AAA screening programme for men aged 65 is shortly to be implemented in England. Trials that have provided evidence for this screening programme have not included information on ethnicity. Hence their findings may not be applicable to ethnically diverse populations. REPORT: This study retrospectively looked at the prevalence of AAA in men aged 65, from different ethnic backgrounds in our city's current screening programme.19014 men (Caucasians n=18,431, Asian n=446, others n=137) were screened. Prevalence was 4.69% (4.39-5% 95% CI), and 0.45% (0.054-1.161% 95% CI) in Caucasians and Asians respectively (Fisher's exact test: P<0.0001). DISCUSSION: Prevalence of AAAs in men aged 65 of Asian origin appears to be low and so increases uncertainty about cost-effectiveness of screening Asian men.


Asunto(s)
Aneurisma de la Aorta Abdominal/diagnóstico , Aneurisma de la Aorta Abdominal/etnología , Pueblo Asiatico/estadística & datos numéricos , Tamizaje Masivo , Población Blanca/estadística & datos numéricos , Anciano , Aneurisma de la Aorta Abdominal/economía , Análisis Costo-Beneficio , Inglaterra/epidemiología , Humanos , Modelos Logísticos , Masculino , Tamizaje Masivo/economía , Oportunidad Relativa , Selección de Paciente , Valor Predictivo de las Pruebas , Prevalencia , Estudios Retrospectivos , Medición de Riesgo , Servicios Urbanos de Salud
10.
S Afr Med J ; 109(5): 314-318, 2019 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-31131797

RESUMEN

BACKGROUND: Hepatitis A virus (HAV) is the most common cause of viral hepatitis worldwide. Hepatitis A vaccine is not included in the Expanded Programme on Immunisation in South Africa (EPI-SA), as the country is considered to be highly endemic for hepatitis A. OBJECTIVES: To determine the seroprevalence of hepatitis A infection in Western Cape Province (WCP), South Africa. METHODS: We conducted a cross-sectional seroprevalence study in the 1 - 7-year age group in WCP. Our samples (N=482) were blood specimens left over after laboratory testing obtained from referral hospitals between August and October 2015. A Siemens enzyme immunoassay was used to test for total hepatitis A antibodies. We also analysed hepatitis A immunoglobulin G antibody results from the National Health Laboratory Service (NHLS) Disa*Lab database at Groote Schuur Hospital from 2009 to 2014, and included 2009 - 2014 acute hepatitis A (immunoglobulin M-positive) surveillance data from the National Institute for Communicable Diseases to look at trends in notified acute infections over the same period. RESULTS: Our cross-sectional study showed 44.1% seroprevalence in the 1 - 7-year age group. Hepatitis A data from the NHLS database indicated a seroprevalence of <90% up to age 10 years, indicating intermediate endemicity. The surveillance data showed that a substantial number of symptomatic hepatitis A infections occurred in the 7 - 40-year age group, suggesting that an increasing proportion of the population is susceptible to HAV infection. CONCLUSIONS: These results suggest an urgent need for detailed evidence-based considerations to introduce hepatitis A vaccine into the EPI-SA.


Asunto(s)
Anticuerpos de Hepatitis A/análisis , Virus de la Hepatitis A/inmunología , Hepatitis A/epidemiología , Niño , Preescolar , Estudios Transversales , Femenino , Hepatitis A/virología , Humanos , Incidencia , Lactante , Masculino , Estudios Retrospectivos , Factores de Riesgo , Estudios Seroepidemiológicos , Sudáfrica/epidemiología
11.
Equine Vet J ; 51(1): 102-107, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29658149

RESUMEN

BACKGROUND: Equine herpesvirus type 1 (EHV-1) is the cause of respiratory disease, abortion storms, and outbreaks of herpesvirus myeloencephalopathy (EHM). Infection of the spinal cord is characterised by multifocal regions of virally infected vascular endothelium, associated with vasculitis, thrombosis and haemorrhage that result in ischaemia and organ dysfunction. However, the mechanism of thrombosis in affected horses is unknown. OBJECTIVES: To evaluate tissue factor (TF) procoagulant activity and thrombin-antithrombin complex (TAT) levels in horses following infection with EHV-1. STUDY DESIGN: In vitro and in vivo studies following experimental EHV-1 infection. METHODS: Horses were infected with EHV-1 and levels of peripheral blood mononuclear cell (PBMC)-associated TF activity; plasma and cerebrospinal fluid (CSF)-derived microvesicle (MV)-associated TF activity and TAT complexes in plasma were examined. RESULTS: EHV-1 infection increased PBMC TF procoagulant activity in vitro and in vivo. In infected horses, this increase was observed during the acute infection and was most marked at the onset and end of viraemia. However, no significant differences were observed between the horses that showed signs of EHM and the horses that did not develop EHM. Significant changes in MV-associated TF procoagulant activity and TAT complexes were not observed in infected horses. MAIN LIMITATIONS: A small number of horses typically exhibit clinical EHM following experimental infection. CONCLUSIONS: The results indicate that EHV-1 infection increases PBMC-associated TF procoagulant activity in vivo and in vitro. Additional in vivo studies are needed to better understand the role of TF-dependent coagulation during EHM pathogenesis in horses.


Asunto(s)
Coagulación Sanguínea , Infecciones por Herpesviridae/veterinaria , Herpesvirus Équido 1 , Enfermedades de los Caballos/sangre , Animales , Antitrombina III/metabolismo , Femenino , Infecciones por Herpesviridae/sangre , Infecciones por Herpesviridae/virología , Enfermedades de los Caballos/virología , Caballos , Leucocitos Mononucleares/citología , Masculino , Péptido Hidrolasas/metabolismo , Tromboplastina/metabolismo , Viremia/sangre , Viremia/genética , Viremia/veterinaria
12.
Int J Tuberc Lung Dis ; 12(12): 1376-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19017445

RESUMEN

This document outlines the consensus agreement from the Union's BCG Working Group regarding BCG vaccination in HIV-infected infants, in response to recently revised World Health Organization (WHO) guidelines, which make HIV infection in infants a full contraindication to bacille Calmette-Guérin (BCG) vaccination. BCG is one of the most widely given vaccines globally and is safe in immunocompetent individuals. Recent evidence shows that HIV-infected infants who were routinely vaccinated with BCG at birth, when asymptomatic, and who later developed AIDS, are at high risk of developing disseminated BCG disease (estimated incidence 407-1300 per 100 000). The document outlines requirements to implement selective BCG vaccination strategies in infants born to HIV-infected women and strategies to reduce the risk of vertical HIV transmission and disseminated BCG disease in infants.


Asunto(s)
Vacuna BCG/administración & dosificación , Infecciones por VIH/complicaciones , Vacuna BCG/efectos adversos , Humanos , Lactante , Recién Nacido , Vacunación/normas , Organización Mundial de la Salud
13.
Cochrane Database Syst Rev ; (2): CD001729, 2007 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-17443509

RESUMEN

BACKGROUND: Haemophilus influenzae (H. influenzae) is an important cause of meningitis and pneumonia in children. Vaccine cost is a significant barrier to use in low income countries. Determining the size of the effects of the vaccine will enable cost-effectiveness comparisons with competing priorities in low income countries. OBJECTIVES: 1. To determine the effects of conjugate Hib vaccine in preventing Hib disease or death in children under five years of age.2. To determine any variation in effect with type of vaccine, number of doses, age at first dose, in children with known HIV infection, or in high and low income countries.3. To determine any serious adverse outcomes. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 4, 2006); MEDLINE (January 1966 to December 2006); EMBASE (1990 to June 2006) and scanned reference lists and contacting of authors of trial reports. Reports in all languages were considered. SELECTION CRITERIA: All randomised controlled trials (RCTs) or quasi-RCTs of conjugate H. influenzae type b vaccines compared with placebo or no treatment in children who were followed until at least two years of age. DATA COLLECTION AND ANALYSIS: Two review authors independently selected eligible studies and extracted data. MAIN RESULTS: Six studies were included in the review, and four in the meta-analyses. The overall quality of the trials was good. The relative risk for invasive Hib disease was 0.20 (95% confidence interval (CI) 0.07 to 0.54; random-effects model), but there was statistically significant unexplained variation (heterogeneity) in the effects of the four trials in the meta-analysis (P = 0.002). The size of the effects did not appear to differ consistently with different vaccine types, the number of vaccine doses, age at first vaccination or use in high income versus low income countries, but the CIs for the effect estimates were wide. Hib-related mortality data showed a non-significant trend towards benefit (relative risk was 0.29; 95% CI 0.07 to 1.20; random-effects model). The relative risk for all cause mortality in the two trials from which data were available were 1.01 (95% CI 0.38 to 2.67, random-effects model) and 0.97. No serious adverse effects were reported in any of the trials. AUTHORS' CONCLUSIONS: Hib vaccine is safe and effective. In resource-poor settings, decisions to use the vaccine will depend on its cost, the local burden of Hib disease and competing priorities.


Asunto(s)
Infecciones por Haemophilus/prevención & control , Vacunas contra Haemophilus/uso terapéutico , Haemophilus influenzae tipo b , Polisacáridos Bacterianos/uso terapéutico , Países en Desarrollo , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Vacunas Conjugadas/uso terapéutico
14.
Equine Vet J ; 49(5): 629-636, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27864898

RESUMEN

BACKGROUND: Equine herpesvirus-associated myeloencephalopathy is the result of endothelial cell infection of the spinal cord vasculature with equine herpesvirus-1 (EHV-1) during cell-associated viraemia. Endothelial cell infection requires contact between infected peripheral blood mononuclear and endothelial cells. Inflammation generated during viraemia likely upregulates adhesion molecule expression on both cell types increasing contact and facilitating endothelial cell infection. OBJECTIVES: Evaluating the role of anti-inflammatory drugs in decreasing endothelial cell infection with EHV-1. STUDY DESIGN: In vitro assay, crossover design, multiple drug testing. METHODS: In vitro modified infectious centre assay using immortalised carotid artery endothelial cells or primary brain endothelial cells with plaque counts per well as outcome. Cells were either anti-inflammatory drug treated or left untreated. RESULTS: Significant reduction of plaque count when cells were treated compared with untreated cells. No dose-dependent effect when drug concentrations were increased to 10× dose. Treatment of both peripheral blood mononuclear cells (PBMC) and endothelial cells (EC) is required for significant plaque count reduction. MAIN LIMITATIONS: In vitro study. CONCLUSIONS: Anti-inflammatory drugs decrease infection of endothelial cells likely by reducing contact between EHV-1 infected PBMC and endothelial cells in vitro. The role of adhesion molecules in this process needs further investigation. In vitro results suggest anti-inflammatory drug therapy during EHV-1 infection and viraemia in horses could be clinically relevant.


Asunto(s)
Antiinflamatorios/uso terapéutico , Infecciones por Herpesviridae/veterinaria , Herpesvirus Équido 1 , Enfermedades de los Caballos/tratamiento farmacológico , Animales , Células Endoteliales/virología , Infecciones por Herpesviridae/tratamiento farmacológico , Caballos , Leucocitos Mononucleares
15.
Int J Tuberc Lung Dis ; 10(3): 310-6, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16562712

RESUMEN

SETTING: A rural town in South Africa. OBJECTIVE: To compare the performance of Quanti-FERON assays with the tuberculin skin test (TST) for identifying latent tuberculosis infection (LTBI) in a high TB burden community. DESIGN: In a cross-sectional study in healthy adults, we applied the TST and took blood for the three generations of QuantiFERON assays. RESULTS: Of 358 participants whose results were analysed, 291 (81%) had a TST result of > or = 10 mm induration, and 187 (52%) > or = 15 mm. QuantiFERON-TB was positive in 215 (60%), QuantiFERON-TB Gold in 137 (38%), and QuantiFERON-TB Gold (In-Tube method) in 201 (56%). There was poor agreement between TST and QuantiFERON tests, and between the different generations of QuantiFERON tests (kappa = 0.12-0.50). Of the subset with TST indurations > or = 15 mm, 30-56% had negative QuantiFERON tests. However, positive Quanti-FERON tests were associated with males, who have a higher incidence of TB in this area. CONCLUSION: We showed poor agreement between TST and the different QuantiFERON tests in diagnosing LTBI. The surprising discordance between the Quanti-FERON TB Gold and QuantiFERON TB Gold (In-Tube method) tests needs to be investigated further.


Asunto(s)
Interferón gamma/sangre , Prueba de Tuberculina , Tuberculosis/sangre , Tuberculosis/diagnóstico , Adolescente , Adulto , Biomarcadores/sangre , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Incidencia , Masculino , Factores de Riesgo , Población Rural , Sudáfrica/epidemiología , Tuberculosis/epidemiología
16.
Oncogene ; 35(13): 1725-35, 2016 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-26096938

RESUMEN

The epithelial-to-mesenchymal transition (EMT) is a cellular process that functions during embryonic development and tissue regeneration, thought to be aberrantly activated in epithelial-derived cancer and has an important role in the process of metastasis. The transforming growth factor (TGF)-ß signaling pathway is a key inducer of EMT and we have elucidated a posttranscriptional mechanism by which TGFß modulates expression of select transcripts via the RNA-binding protein hnRNP E1 during EMT. One such transcript inhibin ßA is a member of the TGFß superfamily. Here, we show by polysome profiling that inhibin ßA is translationally regulated by TGFß via hnRNP E1. TGFß treatment or knockdown of hnRNP E1 relieves silencing of the inhibin ßA transcript, resulting in increased protein expression and secreted levels of the inhibin ßA homodimer, activin A. Our data indicate that the translational upregulation of inhibin ßA enhances the migration and invasion of cells that have undergone an EMT and promotes cancer progression in vivo.


Asunto(s)
Movimiento Celular/genética , Transición Epitelial-Mesenquimal , Ribonucleoproteínas Nucleares Heterogéneas/fisiología , Subunidades beta de Inhibinas/genética , Invasividad Neoplásica/genética , Factor de Crecimiento Transformador beta/metabolismo , Animales , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Proteínas de Unión al ADN , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/genética , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/ética , Subunidades beta de Inhibinas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones SCID , Ratones Transgénicos , Biosíntesis de Proteínas/efectos de los fármacos , Biosíntesis de Proteínas/genética , Interferencia de ARN/efectos de los fármacos , Proteínas de Unión al ARN , Factor de Crecimiento Transformador beta/farmacología
17.
Pediatr Infect Dis J ; 9(10): 715-7, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2235144

RESUMEN

The purpose of this study was to determine whether nosocomial bacteremias occurred more frequently in patients admitted with severe measles compared with general pediatric admissions. In a retrospective survey of 977 blood culture reports during a 4-year period, 1985 to 1988, the incidence of nosocomial bacteremias in patients with measles was found to be on the average of 3.37/100 admissions/year, approximately 6 times that of general pediatric patients (0.57). Gram-negative organisms (predominantly Klebsiella and Salmonella species) accounted for 86.5% of all isolates from measles patients, with 23% of these being multiply antibiotic-resistant. All the isolates from the general patients were fully susceptible to antibiotics. The duration of hospitalization was more than doubled in both groups of affected patients. The onset of hospital-acquired bacteremias occurred on an average of 11.2 days after admission in the patients with measles and 20.5 days in the general patients. Our findings revealed that nosocomial bacteremias occurred with greater frequency in patients with measles and contributed to the morbidity of these patients.


Asunto(s)
Infección Hospitalaria/etiología , Infecciones por Klebsiella/etiología , Sarampión/complicaciones , Infecciones por Salmonella/etiología , Sepsis/etiología , Adolescente , Bacterias/efectos de los fármacos , Niño , Preescolar , Farmacorresistencia Microbiana , Humanos , Lactante , Estudios Retrospectivos , Factores de Riesgo
18.
Pediatr Infect Dis J ; 6(7): 678-81, 1987 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3302920

RESUMEN

Laryngeal tuberculosis is an extremely rare condition in childhood, although probably less so in the underdeveloped world. We have described two cases treated concurrently in our wards. The first case showed features of a pharyngopalatotonsillar membrane, an exquisitely painful edematous pharynx and larynx and was initially sputum-negative for acid-fast bacilli. This presentation fits the hematogenous form of disease and stresses that: laryngeal tuberculosis is not confined to cases of far advanced pulmonary tuberculosis; tuberculosis should enter the differential diagnosis of pharyngeal, tonsillar and palatal lesions (especially membranoulcerative lesions); and there is a common association between laryngeal and abdominal tuberculosis. Her treatment included a 1-month course of steroids and to date (12 months after onset) she shows no signs of complications. The edematous form of laryngeal tuberculosis may be yet another indication for the use of steroids in tuberculosis. Our second patient presented with prolonged chest symptoms, initial positive sputum for acid-fast bacilli and localized granulomatous laryngeal disease, features of far advanced "adult" disease and bronchogenic laryngeal spread. Laryngeal tuberculosis usually responds rapidly to antituberculosis chemotherapy. This was clinically and endoscopically confirmed in both our cases.


Asunto(s)
Tuberculosis Laríngea , Antituberculosos/uso terapéutico , Niño , Quimioterapia Combinada , Femenino , Humanos , Prednisona/uso terapéutico , Tuberculosis Laríngea/diagnóstico , Tuberculosis Laríngea/tratamiento farmacológico , Tuberculosis Laríngea/etiología
19.
Pediatr Infect Dis J ; 13(12): 1107-10, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7892079

RESUMEN

The antibiotic management of 139 consecutive patients with presumed viral meningitis evaluated during a 6-month period was examined. The presumptive diagnosis of viral meningitis was made in retrospect by consensus among the authors, using clinical and routinely available laboratory information. Sixty-eight (51.9%) of 131 patients with complete records were treated with antibiotics after diagnosis, 25 for 2 days or less and 43 for longer than 2 days. Antibiotic treatment was retrospectively judged to be unjustified in 35 (81.4%) of the 43 patients treated for longer than 2 days. When compared with untreated patients antibiotic treatment was started in younger female children with lower cerebrospinal fluid glucose values and longer duration of symptoms. There was no difference between the two groups in other cerebrospinal fluid values, peripheral white blood cell count or history of preceding antibiotics. In contrast no associations were found with treatment beyond 2 days, compared with treatment for 2 days or less. Thus the decision to stop antibiotic treatment early did not appear to be made according to consistent clinical criteria. This apparent lack of consistent criteria suggests the need to develop clinical guidelines for such decisions, both to aid clinicians and to provide standards for medical audit.


Asunto(s)
Antibacterianos/uso terapéutico , Meningitis Viral/tratamiento farmacológico , Pautas de la Práctica en Medicina , Niño , Preescolar , Utilización de Medicamentos/tendencias , Femenino , Humanos , Lactante , Masculino , Auditoría Médica , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos , Sudáfrica
20.
Pediatr Infect Dis J ; 10(11): 832-6, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1749696

RESUMEN

This is a retrospective review of the clinical, radiologic and laboratory features of 94 cases of childhood miliary tuberculosis seen during a 5-year period, 1985 to 1989. A history of Bacillus Calmette-Guérin vaccination was documented in 88% of children. The median age at presentation was 10.5 months, 52% of cases occurring in those younger than 1 year. The presenting symptoms were nonspecific: cough (72%); fever (61%); loss of appetite and weight (40%); and diarrhea and vomiting (33%). The main presenting signs were hepatomegaly (82%), splenomegaly (54%), lymphadenopathy (46%) and pyrexia (39%). Most of the patients were malnourished and anergic. Meningitis occurred in 19% of patients and this was the only significant risk factor identified for mortality, the overall case fatality rate being 14%. The diagnosis in the vast majority was made on the clinical presentation supported by a classic miliary pattern on chest roentgenogram (91% of cases). Mycobacterium tuberculosis was cultured in 33% of cases. In addition a review of hospital admissions from 1981 to 1989 revealed that annually miliary tuberculosis in children and adults accounted for 8.3 and 1.3%, respectively, of all tuberculosis admissions. This study confirms that miliary tuberculosis is a relatively common complication of tuberculosis in young children.


Asunto(s)
Tuberculosis Miliar/epidemiología , Adolescente , Adulto , Factores de Edad , Vacuna BCG , Niño , Preescolar , Factores Epidemiológicos , Femenino , Humanos , Lactante , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sudáfrica/epidemiología , Análisis de Supervivencia , Tuberculosis Meníngea/epidemiología , Tuberculosis Miliar/diagnóstico , Tuberculosis Miliar/tratamiento farmacológico
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