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1.
Emerg Infect Dis ; 28(13): S203-S207, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36502406

RESUMEN

Global emergence of the COVID-19 pandemic in 2020 curtailed vaccine-preventable disease (VPD) surveillance activities, but little is known about which surveillance components were most affected. In May 2021, we surveyed 214 STOP (originally Stop Transmission of Polio) Program consultants to determine how VPD surveillance activities were affected by the COVID-19 pandemic throughout 2020, primarily in low- and middle-income countries, where program consultants are deployed. Our report highlights the responses from 154 (96%) of the 160 consultants deployed to the World Health Organization African Region, which comprises 75% (160/214) of all STOP Program consultants deployed globally in early 2021. Most survey respondents observed that VPD surveillance activities were somewhat or severely affected by the COVID-19 pandemic in 2020. Reprioritization of surveillance staff and changes in health-seeking behaviors were factors commonly perceived to decrease VPD surveillance activities. Our findings suggest the need for strategies to restore VPD surveillance to prepandemic levels.


Asunto(s)
COVID-19 , Poliomielitis , Enfermedades Prevenibles por Vacunación , Humanos , Enfermedades Prevenibles por Vacunación/epidemiología , Enfermedades Prevenibles por Vacunación/prevención & control , Pandemias/prevención & control , COVID-19/epidemiología , COVID-19/prevención & control , Poliomielitis/epidemiología , Organización Mundial de la Salud
2.
Clin Exp Immunol ; 210(2): 151-162, 2022 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-36181724

RESUMEN

The clinical usefulness of post-diagnosis islet autoantibody levels is unclear and factors that drive autoantibody persistence are poorly defined in type 1 diabetes (T1D). Our aim was to characterise the longitudinal loss of islet autoantibody responses after diagnosis in a large, prospectively sampled UK cohort. Participants with T1D [n = 577] providing a diagnosis sample [range -1.0 to 2.0 years] and at least one post-diagnosis sample (<32.0 years) were tested for autoantibodies to glutamate decarboxylase 65 (GADA), islet antigen-2 (IA-2A), and zinc transporter 8 (ZnT8A). Select HLA and non-HLA SNPs were considered. Non-genetic and genetic factors were assessed by multivariable logistic regression models for autoantibody positivity at initial sampling and autoantibody loss at final sampling. For GADA, IA-2A, and ZnT8A, 70.8%, 76.8%, and 40.1%, respectively, remained positive at the final sampling. Non-genetic predictors of autoantibody loss were low baseline autoantibody titres (P < 0.0001), longer diabetes duration (P < 0.0001), and age-at-onset under 8 years (P < 0.01--0.05). Adjusting for non-genetic covariates, GADA loss was associated with low-risk HLA class II genotypes (P = 0.005), and SNPs associated with autoimmunity RELA/11q13 (P = 0.017), LPP/3q28 (P = 0.004), and negatively with IFIH1/2q24 (P = 0.018). IA-2A loss was not associated with genetic factors independent of other covariates, while ZnT8A loss was associated with the presence of HLA A*24 (P = 0.019) and weakly negatively with RELA/11q13 (P = 0.049). The largest longitudinal study of islet autoantibody responses from diagnosis of T1D shows that autoantibody loss is heterogeneous and influenced by low titres at onset, longer duration, earlier age-at-onset, and genetic variants. These data may inform clinical trials where post-diagnosis participants are recruited.


Asunto(s)
Diabetes Mellitus Tipo 1 , Humanos , Niño , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/genética , Glutamato Descarboxilasa , Estudios Longitudinales , Estudios de Seguimiento , Autoanticuerpos
3.
Clin Exp Immunol ; 203(1): 41-46, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32979862

RESUMEN

During a 15-year period, the incidence of type 1 diabetes has doubled in Lithuania, while increasing by a third in England; however, England still has a higher incidence. Analysis of sera collected from non-diabetic schoolchildren from Lithuania and England more than 20 years ago showed a similar number of multiple autoantibody-positive schoolchildren between the populations, but a higher prevalence of islet antigen-2 autoantibodies (IA-2A) in English schoolchildren. We aimed to use recently developed, more specific islet autoantibody tests to characterize differences in humoral autoimmunity between these two general population cohorts in greater detail. Samples from 88 Lithuanian and 133 English schoolchildren previously found islet autoantibody-positive were selected for measurement of additional islet autoantibodies by radioimmunoassay. Samples were tested for autoantibodies to zinc transporter 8 (ZnT8A), GAD (96-585), the protein tyrosine phosphatase region of islet antigen-2 (PTPA) and the related IA-2ßA, while autoantibodies to IA-2A were reassayed using the current harmonized method. IA-2-related autoantibodies PTPA (0·13 versus 0·45%, P = 0·027) and IA-2ßA (0 versus 0·35%, P < 0·001), but not IA-2A measured using the harmonized method, were less common in Lithuanian compared to English schoolchildren. Lithuanian schoolchildren who were islet autoantibody-positive were positive for fewer biochemical autoantibodies compared with English schoolchildren (P = 0·043). Background rates of islet autoimmunity in childhood differ subtly between countries, which have different incidences of type 1 diabetes. The optimal screening strategy (age and combination of markers) for detection of islet autoimmunity may vary between countries, dependent upon the pattern of autoantibodies found in the general population.


Asunto(s)
Autoanticuerpos/sangre , Diabetes Mellitus Tipo 1/sangre , Islotes Pancreáticos/metabolismo , Adolescente , Autoanticuerpos/inmunología , Niño , Preescolar , Diabetes Mellitus Tipo 1/inmunología , Inglaterra , Femenino , Glutamato Descarboxilasa/inmunología , Glutamato Descarboxilasa/metabolismo , Humanos , Islotes Pancreáticos/inmunología , Lituania , Masculino , Fosfoproteínas Fosfatasas/inmunología , Fosfoproteínas Fosfatasas/metabolismo , Transportador 8 de Zinc/inmunología , Transportador 8 de Zinc/metabolismo
4.
J Public Health (Oxf) ; 42(1): e96-e104, 2020 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-31220298

RESUMEN

BACKGROUND: The UK has one of the highest prevalence rates of obesity worldwide. Public health departments have a duty to provide some obesity treatment and prevention services. With evidence of effective programmes lacking, we investigate lessons learned from a healthy weight programme in Cornwall, UK. METHODS: Data from the 12-week multi-component adult healthy weight management programme were obtained for 2012-2016. Descriptive statistics and statistical tests were used to describe participants' demographics, health status and anthropometric measures to explore the enrolment and retention of the programme as well as the impact. RESULTS: A total of 1872 adults were referred into the programme. Overall, 646 completed the programme and, 48.8% achieved the programme's aim of a >3% reduction in weight. Those who completed and met the programme aim tended to have had healthier outcomes at baseline. CONCLUSIONS: For those who engage with the programme the impact can be meaningful. However, <1% of the population of Cornwall with overweight or obesity enroled in the programme, and those who benefitted most might have been in least need. Providing services that meet the needs of the population is challenging when a variety of services is needed, and the evidence base is poor.


Asunto(s)
Obesidad , Sobrepeso , Adulto , Peso Corporal , Promoción de la Salud , Humanos , Obesidad/epidemiología , Obesidad/prevención & control , Sobrepeso/epidemiología , Sobrepeso/prevención & control , Reino Unido/epidemiología
5.
Eur J Public Health ; 30(3): 595-600, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-31711154

RESUMEN

BACKGROUND: Service centres for homeless adults are potential settings for implementation of reintegration interventions. This study aimed to evaluate (i) the acceptability of a group-based programme among individuals from the broad population of homeless people and (ii) if a future study of its feasibility and acceptability for re-housed homeless people is warranted. METHODS: Recruiting participants and intervention facilitators from partnering service centres was thought to improve recruitment and retention, cost-effectiveness and social interactions compared to professional-led interventions. Seven adults with experience of homelessness (three females, four males, mean age 39 years, range 18-63) were recruited to participate in the intervention. The research protocol comprised completion pre/post of scales [Recovering Quality of Life questionnaire; Working Alliance Inventory-short form revised (WAI-SR)] and focus groups, and WAI-SR and focus groups after sessions 3 and 6. RESULTS: The intervention and research protocols were feasible, with all participants engaging in all sessions, completing all scales and attending all focus groups. The quantitative data demonstrated the feasibility of obtaining practically useful measures of relevant outcomes. In the four focus groups, the intervention received very favourable feedback. CONCLUSIONS: This study demonstrated initial feasibility and acceptability of an intervention that places minimal burden on infrastructure and promotes user autonomy. This is an important advance as there is increasing recognition that the challenge of reintegration is as much a psychological and social problem as a housing problem. If effective, this style of intervention may serve as a template for future interventions with similar populations.


Asunto(s)
Personas con Mala Vivienda , Calidad de Vida , Adolescente , Adulto , Estudios de Factibilidad , Femenino , Vivienda , Humanos , Masculino , Persona de Mediana Edad , Problemas Sociales , Adulto Joven
6.
Clin Exp Immunol ; 192(3): 251-258, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29431870

RESUMEN

Individuals with type 1 diabetes (T1D) are at increased risk of coeliac disease (CD), autoimmune thyroiditis and autoimmune gastritis, but the absolute risks are unclear. The aim of this study was to investigate the prevalence of autoantibodies to tissue transglutaminase (TGA), thyroid peroxidase (TPOA) and gastric H+ /K+ -ATPase (ATPA) and their genetic associations in a well-characterized population-based cohort of individuals with T1D from the Bart's-Oxford family study for whom islet autoantibody prevalence data were already available. Autoantibodies in sera from 1072 patients (males/females 604/468; median age 11·8 years, median T1D duration 2·7 months) were measured by radioimmunoassays; HLA class II risk genotype was analysed in 973 (91%) using polymerase chain reaction with sequence specific primers (PCR-SSP). The prevalence of TGA (and/or history of CD), TPOA and ATPA in patients was 9·0, 9·6 and 8·2%, respectively; 3·1% had two or more autoantibodies. Females were at higher risk of multiple autoimmunity; TGA/CD were associated with younger age and TPOA with older age. ATPA were uncommon in patients under 5 years, and more common in older patients. Anti-glutamate decarboxylase autoantibodies were predictive of co-existing TPOA/ATPA. TGA/CD were associated with human leucocyte antigen (HLA) DR3-DQ2, with the DR3-DQ2/DR3-DQ2 genotype conferring the highest risk, followed by DR4-DQ8/DR4-DQ8. ATPA were associated with DR3-DQ2, DRB1*0404 (in males) and the DR3-DQ2/DR4-DQ8 genotype. TPOA were associated with the DR3-DQ2/DR3-DQ2 genotype. Almost one-quarter of patients diagnosed with T1D aged under 21 years have at least one other organ-specific autoantibody. HLA class II genetic profiling may be useful in identifying those at risk of multiple autoimmunity.


Asunto(s)
Autoanticuerpos/inmunología , Autoantígenos/inmunología , Autoinmunidad/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/inmunología , Proteínas de Unión al GTP/inmunología , Glutamato Descarboxilasa/inmunología , ATPasa Intercambiadora de Hidrógeno-Potásio/inmunología , Yoduro Peroxidasa/inmunología , Proteínas de Unión a Hierro/inmunología , Transglutaminasas/inmunología , Adolescente , Adulto , Enfermedad Celíaca/genética , Niño , Preescolar , Femenino , Predisposición Genética a la Enfermedad/genética , Antígenos HLA-DQ/genética , Antígeno HLA-DR3/genética , Humanos , Lactante , Masculino , Proteína Glutamina Gamma Glutamiltransferasa 2 , Radioinmunoensayo , Gastropatías/genética , Enfermedades de la Tiroides/genética , Reino Unido , Adulto Joven
7.
Diabet Med ; 35(7): 954-963, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29577424

RESUMEN

AIMS: Glutamate decarboxylase (GAD) antibodies are the most widely used predictive marker for Type 1 diabetes, but many individuals currently found to be GAD antibody-positive are unlikely to develop diabetes. We have shown previously that radioimmunoassays using N-terminally truncated 35 S-GAD65 (96-585) offer better disease specificity with similar sensitivity to full-length 35 S-GAD65 (1-585). To determine whether assay performance could be improved further, we evaluated a more radically truncated 35 S-GAD65 (143-585) radiolabel. METHODS: Samples from people with recent-onset Type 1 diabetes (n = 157) and their first-degree relatives (n = 745) from the Bart's-Oxford family study of childhood diabetes were measured for GAD antibodies using 35 S-labelled GAD65 (143-585). These were screened previously using a local radioimmunoassay with 35 S-GAD65 (1-585). A subset was also tested by enzyme-linked immunosorbent assay (ELISA), which performs well in international workshops, but requires 10 times more serum. Results were compared with GAD antibody measurements using 35 S-GAD65 (1-585) and 35 S-GAD65 (96-585). RESULTS: Sensitivity of GAD antibody measurement was maintained using 35 S-GAD65 (143-585) compared with 35 S-GAD65 (1-585) and 35 S-GAD65 (96-585). Specificity for Type 1 diabetes was improved compared with 35 S-GAD65 (1-585), but was similar to 35 S-GAD65 (96-585). Relatives found to be GAD antibody-positive using these truncated labels were at increased risk of diabetes progression within 15 years, compared with those positive for GAD(1-585) antibody only, and at similar risk to those found GAD antibody-positive by ELISA. CONCLUSIONS: The first 142 amino acids of GAD65 do not contribute to epitopes recognized by Type 1 diabetes-associated GAD antibodies. Low-volume radioimmunoassays using N-terminally truncated 35 S-GAD65 are more specific than those using full-length GAD65 and offer practical alternatives to the GAD antibody ELISA for identifying children at increased risk of Type 1 diabetes.


Asunto(s)
Autoanticuerpos/inmunología , Diabetes Mellitus Tipo 1/inmunología , Glutamato Descarboxilasa/inmunología , Fragmentos de Péptidos/inmunología , Adolescente , Adulto , Anciano , Niño , Preescolar , Diabetes Mellitus Tipo 1/diagnóstico , Ensayo de Inmunoadsorción Enzimática , Epítopos/inmunología , Familia , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Radioinmunoensayo , Sensibilidad y Especificidad , Adulto Joven
8.
J Invertebr Pathol ; 127: 122-6, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25819846

RESUMEN

The Giant African snail (Achatina fulica) is a major pest in tropical countries. Current control methods involve the use of slug pellets (metaldehyde) but they are ineffective, therefore new methods of control are needed. We investigated whether A. fulica is susceptible to the gastropod parasitic nematode Phasmarhabditis hermaphrodita, which has been developed as a biological control agent for slugs and snails in northern Europe. We exposed A. fulica to P. hermaphrodita applied at 30 and 150nematodes per cm(2) for 70days and also assessed feeding inhibition and changes in snail weight. We show that unlike the susceptible slug species Deroceras panormitanum, which is killed less than 30days of exposure to P. hermaphrodita, A. fulica is remarkably resistant to the nematode at both doses. Also P. hermaphrodita does not reduce feeding in A. fulica nor did it have any effect on weight gain over 70days. Upon dissection of infected A. fulica we found that hundreds of P. hermaphrodita had been encapsulated, trapped and killed in the snail's shell. We found that A. fulica is able to begin encapsulating P. hermaphrodita after just 3days of exposure and the numbers of nematodes encapsulated increased over time. Taken together, we have shown that A. fulica is highly resistant to P. hermaphrodita, which could be due to an immune response dependent on the snail shell to encapsulate and kill invading parasitic nematodes.


Asunto(s)
Control Biológico de Vectores/métodos , Caracoles/inmunología , Caracoles/parasitología , Animales , Europa (Continente) , Rhabditoidea/inmunología
9.
J Virol ; 87(9): 4907-22, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23408630

RESUMEN

Since 2005, a large poliomyelitis outbreak associated with type 2 circulating vaccine-derived poliovirus (cVDPV2) has occurred in northern Nigeria, where immunization coverage with trivalent oral poliovirus vaccine (tOPV) has been low. Phylogenetic analysis of P1/capsid region sequences of isolates from each of the 403 cases reported in 2005 to 2011 resolved the outbreak into 23 independent type 2 vaccine-derived poliovirus (VDPV2) emergences, at least 7 of which established circulating lineage groups. Virus from one emergence (lineage group 2005-8; 361 isolates) was estimated to have circulated for over 6 years. The population of the major cVDPV2 lineage group expanded rapidly in early 2009, fell sharply after two tOPV rounds in mid-2009, and gradually expanded again through 2011. The two major determinants of attenuation of the Sabin 2 oral poliovirus vaccine strain (A481 in the 5'-untranslated region [5'-UTR] and VP1-Ile143) had been replaced in all VDPV2 isolates; most A481 5'-UTR replacements occurred by recombination with other enteroviruses. cVDPV2 isolates representing different lineage groups had biological properties indistinguishable from those of wild polioviruses, including efficient growth in neuron-derived HEK293 cells, the capacity to cause paralytic disease in both humans and PVR-Tg21 transgenic mice, loss of the temperature-sensitive phenotype, and the capacity for sustained person-to-person transmission. We estimate from the poliomyelitis case count and the paralytic case-to-infection ratio for type 2 wild poliovirus infections that ∼700,000 cVDPV2 infections have occurred during the outbreak. The detection of multiple concurrent cVDPV2 outbreaks in northern Nigeria highlights the risks of cVDPV emergence accompanying tOPV use at low rates of coverage in developing countries.


Asunto(s)
Poliomielitis/epidemiología , Vacuna Antipolio Oral/efectos adversos , Vacunas contra Poliovirus/efectos adversos , Poliovirus/fisiología , Animales , Proteínas de la Cápside/genética , Proteínas de la Cápside/inmunología , Brotes de Enfermedades , Femenino , Humanos , Masculino , Ratones , Datos de Secuencia Molecular , Nigeria/epidemiología , Filogenia , Poliomielitis/virología , Poliovirus/clasificación , Poliovirus/genética , Poliovirus/inmunología , Vacuna Antipolio Oral/administración & dosificación , Vacunas contra Poliovirus/genética , Vacunas contra Poliovirus/inmunología
10.
J Fish Biol ; 84(4): 1074-98, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24641275

RESUMEN

The effects of size and age on reproductive dynamics of common coral trout Plectropomus leopardus populations were compared between coral reefs open or closed (no-take marine reserves) to fishing and among four geographic regions of the Great Barrier Reef (GBR), Australia. The specific reproductive metrics investigated were the sex ratio, the proportion of vitellogenic females and the spawning fraction of local populations. Sex ratios became increasingly male biased with length and age, as expected for a protogyne, but were more male biased in southern regions of the GBR (Mackay and Storm Cay) than in northern regions (Lizard Island and Townsville) across all lengths and ages. The proportion of vitellogenic females also increased with length and age. Female P. leopardus were capable of daily spawning during the spawning season, but on average spawned every 4·3 days. Mature females spawned most frequently on Townsville reserve reefs (every 2·3 days) and Lizard Island fished reefs (every 3·2 days). Females on Mackay reefs open to fishing showed no evidence of spawning over 4 years of sampling, while females on reserve reefs spawned only once every 2-3 months. No effect of length on spawning frequency was detected. Spawning frequency increased with age on Lizard Island fished reefs, declined with age on Storm Cay fished reefs, and declined with age on reserve reefs in all regions. It is hypothesized that the variation in P. leopardus sex ratios and spawning frequency among GBR regions is primarily driven by water temperature, while no-take management zones influence spawning frequency depending on the region in which the reserve is located. Male bias and lack of spawning activity on southern GBR, where densities of adult P. leopardus are highest, suggest that recruits may be supplied from central or northern GBR. Significant regional variation in reproductive traits suggests that a regional approach to management of P. leopardus is appropriate and highlights the need for considering spatial variation in reproduction where reserves are used as fishery or conservation management tools.


Asunto(s)
Lubina/fisiología , Tamaño Corporal , Reproducción/fisiología , Animales , Australia , Arrecifes de Coral , Femenino , Explotaciones Pesqueras , Geografía , Masculino , Modelos Estadísticos , Razón de Masculinidad , Maduración Sexual
11.
Nat Genet ; 12(2): 159-67, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8563754

RESUMEN

The t(7;11)(p15;p15) translocation is a recurrent chromosomal abnormality associated primarily with acute myeloid leukaemia (FAB M2 and M4). We present here the molecular definition of this translocation. On chromosome 7 positional cloning revealed the consistent rearrangement of the HOXA9 gene, which encodes a class I homeodomain protein potentially involved in myeloid differentiation. On chromosome 11 the translocation targets the human homologue of NUP98, a member of the GLFG nucleoporin family. Chimaeric messages spliced over the breakpoint fuse the GLFG repeat domains of NUP98 in-frame to the HOXA9 homeobox. The predicted NUP98-HOXA9 fusion protein may promote leukaemogenesis through inhibition of HOXA9-mediated terminal differentiation and/or aberrant nucleocytoplasmic transport.


Asunto(s)
Cromosomas Humanos Par 11 , Cromosomas Humanos Par 7 , Proteínas de Homeodominio/genética , Leucemia Mielomonocítica Aguda/genética , Proteínas de la Membrana/genética , Proteínas de Complejo Poro Nuclear , Proteínas Nucleares/genética , Translocación Genética , Secuencia de Aminoácidos , Secuencia de Bases , Mapeo Cromosómico , Clonación Molecular , Proteínas de Homeodominio/fisiología , Humanos , Datos de Secuencia Molecular , ARN Mensajero/genética , ARN Neoplásico/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Análisis de Secuencia de ADN
12.
J Fish Biol ; 82(5): 1523-44, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23639152

RESUMEN

Validated estimates of age are presented for albacore Thunnus alalunga, sampled from a large part of the south-western Pacific Ocean, based on counts of annual opaque growth zones from transverse sections of otoliths. Counts of daily increments were used to estimate the location of the first opaque growth zone, which was completed before the first assumed birthday. The periodicity of opaque zones was estimated by marginal increment analysis and an oxytetracycline mark-recapture experiment. Both validation methods indicated that opaque zones formed over the austral summer and were completed by autumn to winter (April to August). The direct comparison of age estimates obtained from otoliths and dorsal-fin spines of the same fish indicated bias, which was assumed to be due to poor increment clarity and resorption of early growth zones in spines, resulting in imprecise age estimates. As such, age estimates from otoliths are considered to be more accurate than those from spines for T. alalunga. This is consistent with results for a growing number of tropical and temperate tuna Thunnini species. It is recommend that validated counts of annual growth zones from sectioned otoliths is used as the preferred method for estimating age-based parameters for assessment and management advice for these important stocks.


Asunto(s)
Envejecimiento/fisiología , Perciformes/fisiología , Aletas de Animales/anatomía & histología , Animales , Océano Pacífico , Perciformes/anatomía & histología , Reproducibilidad de los Resultados
13.
J Fish Biol ; 82(3): 764-88, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23464543

RESUMEN

Life-history characteristics of six tropical Lethrinus species sampled from the Great Barrier Reef World Heritage Area were compared. Two species groups were identified based on fork length (LF ): large species with maximum LF > 640 mm (longface emperor Lethrinus olivaceus, yellowlip emperor Lethrinus xanthochilus and spangled emperor Lethrinus nebulosus) and small species with maximum LF < 480 mm (Pacific yellowtail emperor Lethrinus atkinsoni, pink ear emperor Lethrinus lentjan and ornate emperor Lethrinus ornatus). Lifespan was not correlated with LF . Early growth for all species was rapid and similar during the first few years of life, but coefficients of the von Bertalanffy growth function varied considerably among species. Growth also differed between sexes for L. atkinsoni. Reproductive characteristics varied among species, with peak periods of spawning occurring in November to December for L. atkinsoni, July to August for L. nebulous, September to October for L. olivaceus and a protracted season for L. lentjan, although fewer samples were available for the last two species. Sex-specific LF and age distributions and gonad histology of L. lentjan were suggestive of a functional protogynous reproductive pattern, as observed in other lethrinids. Gonad histology indicated non-functional protogynous hermaphroditism for L. atkinsoni and L. nebulosus. The diversity of life histories among these closely related species emphasizes the difficulty in devising single management strategies appropriate for multi-species fisheries and illustrates the importance of understanding species-specific life histories to infer responses to exploitation.


Asunto(s)
Perciformes/fisiología , Reproducción , Distribución por Edad , Animales , Australia , Tamaño Corporal , Femenino , Masculino , Perciformes/crecimiento & desarrollo , Estaciones del Año , Especificidad de la Especie
14.
Talanta ; 257: 124283, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36870123

RESUMEN

One of the main objectives of present and future space exploration missions dedicated to astrobiology is the detection of organic molecules of interest for life (e.g. amino and fatty acids). With this aim, a sample preparation and a gas chromatograph (connected to a mass spectrometer) are generally used. To date, tetramethylammonium hydroxide (TMAH) has been the first and only thermochemolysis reagent to be used for in situ sample preparation and chemical analysis of planetary environments. Although TMAH is widely used in terrestrial laboratories, numerous applications also leverage other thermochemolysis reagents that may be more relevant than TMAH to meet both scientific and technical objectives of space instrumentation. The present study compares the performance of tetramethylammonium hydroxide (TMAH), trimethylsulfonium hydroxide (TMSH), and trimethylphenylammonium hydroxide (TMPAH) reagents on molecules of interest to astrobiology. The study focuses on the analyses of 13 carboxylic acids (C7-C30), 17 proteinic amino acids, and the 5 nucleobases. Here we report the derivatization yield without stirring or adding solvents, the detection sensitivity with mass spectrometry, and the nature of the degradation products from the reagents produced during pyrolysis. We conclude that TMSH and TMAH are the best reagents for analyzing carboxylic acids and nucleobases. Amino acids are not relevant targets for a thermochemolysis over 300 °C as they are degraded and showed high limits of detection. As TMAH, and probably TMSH, meet the space instrumentation requirements, this study informs sample treatment approaches prior to GC-MS analysis in in situ space studies. The thermochemolysis reaction using TMAH or TMSH is also recommended for space return missions to extract organics from a macromolecular matrix, derivatize polar or refractory organic targets, and volatilize with the fewest organic degradations.

15.
Diabetologia ; 55(7): 1873-6, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22610401

RESUMEN

Autoantibodies to islet cell proteins currently provide the only reliable indication that the process leading to type 1 diabetes has started. The period from the first detection of islet autoantibodies to clinical onset of diabetes can last months or years. Longitudinal birth cohort family studies give crucial information concerning the natural history of islet autoimmunity and have already shown that islet autoantibodies, which precede diabetes development, often appear in early infancy. In this issue of Diabetologia, Ziegler et al (DOI: 10.1007/s00125-012-2472-x ) and Parikka et al (DOI: 10.1007/s00125-012-2523-3 ) report findings from their birth cohort studies after numerous children have entered adolescence, allowing a more complete picture of islet autoimmunity in childhood to be revealed. Both groups are in accord that, between 6 months and 3 years of age, there is an explosion of islet autoimmunity in susceptible children and that the great majority (approximately 80%) of genetically at-risk children who present with diabetes before adolescence develop islet autoimmunity at this young age. These findings emphasise the importance of early life events in disease pathogenesis and have major implications for efforts aimed at preventing type 1 diabetes.


Asunto(s)
Autoanticuerpos/sangre , Hijo de Padres Discapacitados , Diabetes Mellitus Tipo 1/inmunología , Antígenos HLA/inmunología , Antígenos HLA-D/inmunología , Estado Prediabético/inmunología , Femenino , Humanos , Masculino , Embarazo
16.
Clin Exp Immunol ; 167(1): 67-72, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22132886

RESUMEN

Development of high-risk combinations of multiple islet autoantibodies and type 1 diabetes is associated with high-affinity insulin autoantibodies (IAA), but IAA affinity measurements require large serum volumes. We therefore investigated whether a simplified method of IAA affinity measurement using a low concentration of unlabelled insulin (ULI) competitor discriminated between moderate-high- and low-affinity IAA and identified individuals at highest risk of disease. Samples were assayed by radiobinding microassay using high (4·0 × 10(-5) mol/l) and low (7 × 10(-9) mol/l) ULI concentrations for competitive displacement in three cohorts of IAA-positive individuals; (1) 68 patients with newly-diagnosed type 1 diabetes; (2) 40 healthy schoolchildren; and (3) 114 relatives of patients with type 1 diabetes followed prospectively for disease development (median follow-up 13 years). IAA results obtained with low ULI were expressed as a percentage of those obtained with high ULI and this was used to classify samples as low or moderate-high affinity (0-50% and >50%, respectively). Sixty-eight patient samples were positive with high and 67 (99%) with low ULI. Forty schoolchildren were IAA-positive with high and 22 (55%) with low ULI (P < 0·001). Of the relatives, 113 were positive with high and 83 (73%) with low ULI (P < 0·001). In relatives, moderate-high affinity IAA were associated with multiple islet antibodies (P < 0·001) and greater diabetes risk than low affinity IAA (P < 0·001). A single low concentration of ULI competitor can act as a surrogate for complex IAA affinity measurements and identifies those IAA-positive relatives at highest risk of disease progression.


Asunto(s)
Afinidad de Anticuerpos , Autoanticuerpos/inmunología , Autoantígenos/inmunología , Diabetes Mellitus Tipo 1/inmunología , Insulina/inmunología , Radioinmunoensayo/métodos , Adolescente , Adulto , Autoanticuerpos/sangre , Unión Competitiva , Niño , Preescolar , Diabetes Mellitus Tipo 1/genética , Salud de la Familia , Femenino , Estudios de Seguimiento , Glutamato Descarboxilasa/inmunología , Humanos , Islotes Pancreáticos/inmunología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Riesgo , Adulto Joven
17.
Vet Pathol ; 49(6): 1049-53, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22390882

RESUMEN

The cervical spinal cords of 2 horses with equine degenerative myeloencephalopathy (EDM) were evaluated for evidence of oxidative damage to the central nervous system (CNS) using immunohistochemical staining for 3-nitrotyrosine (3-NT) and 4-hydroxynonenol (4-HNE). Neurons of the CNS from horses with EDM had positive immunohistochemical staining, whereas control samples did not, thus supporting the theory that oxidative damage is a potential underlying factor in horses with EDM. In addition, serum vitamin E concentration was low in both EDM-affected horses, and vitamin E concentration was also deficient in the cerebrospinal fluid in 1 EDM horse, further supporting the association between low vitamin E concentrations and oxidative damage to the CNS. Continued research is necessary to further define the pathophysiologic mechanisms of EDM.


Asunto(s)
Encefalopatías/veterinaria , Enfermedades de los Caballos/diagnóstico , Enfermedades Neurodegenerativas/veterinaria , Enfermedades de la Médula Espinal/veterinaria , Aldehídos/análisis , Animales , Ataxia/veterinaria , Encefalopatías/diagnóstico , Encefalopatías/patología , Sistema Nervioso Central/patología , Femenino , Enfermedades de los Caballos/patología , Caballos , Inmunohistoquímica/veterinaria , Enfermedades Neurodegenerativas/diagnóstico , Enfermedades Neurodegenerativas/patología , Estrés Oxidativo , Enfermedades de la Médula Espinal/diagnóstico , Enfermedades de la Médula Espinal/patología , Tirosina/análogos & derivados , Tirosina/análisis , Vitamina E/líquido cefalorraquídeo , Deficiencia de Vitamina E/veterinaria
18.
J Infect Dis ; 203(7): 898-909, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21402542

RESUMEN

Wild poliovirus has remained endemic in northern Nigeria because of low coverage achieved in the routine immunization program and in supplementary immunization activities (SIAs). An outbreak of infection involving 315 cases of type 2 circulating vaccine-derived poliovirus (cVDPV2; >1% divergent from Sabin 2) occurred during July 2005-June 2010, a period when 23 of 34 SIAs used monovalent or bivalent oral poliovirus vaccine (OPV) lacking Sabin 2. In addition, 21 "pre-VDPV2" (0.5%-1.0% divergent) cases occurred during this period. Both cVDPV and pre-VDPV cases were clinically indistinguishable from cases due to wild poliovirus. The monthly incidence of cases increased sharply in early 2009, as more children aged without trivalent OPV SIAs. Cumulative state incidence of pre-VDPV2/cVDPV2 was correlated with low childhood immunization against poliovirus type 2 assessed by various means. Strengthened routine immunization programs in countries with suboptimal coverage and balanced use of OPV formulations in SIAs are necessary to minimize risks of VDPV emergence and circulation.


Asunto(s)
Brotes de Enfermedades , Poliomielitis/epidemiología , Poliomielitis/virología , Vacunas contra Poliovirus/efectos adversos , Poliovirus/aislamiento & purificación , Poliovirus/patogenicidad , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Genoma Viral , Política de Salud , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Mutación , Nigeria/epidemiología , Poliomielitis/patología , Poliovirus/genética , Vacunas contra Poliovirus/administración & dosificación , Vacunación/estadística & datos numéricos , Adulto Joven
19.
Front Psychiatry ; 13: 916164, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36061288

RESUMEN

This study was the first to determine whether it was feasible and acceptable to use experience sampling methods (ESM) among LGBTQ+ young people, who had current experiences of self-harm. Sixteen LGBTQ+ young people (16-25 years old) took part in the experience sampling study. This included a baseline assessment, a 7-day ESM assessment (participants were sampled six times a day using a phone app), and the option of an interview at the end of the 7-day ESM assessment. Feasibility data was descriptively analysed, with pilot ESM data presented. Qualitative data was thematically analysed to determine the acceptability (barriers and facilitators) of taking part in this study. Study feasibility was assessed by enrolment rate (55.2%), participant retention across assessment period (100%), ESM app feasibility (87.5%), and good adherence to total number of ESM surveys (67.6%). Individual study adherence ranged between 43 and 95.2%. Study acceptability was assessed by participant interviews. Thematic analysis indicated four superordinate themes; (i) Self-reflection and awareness; (ii) Practicalities of ESM surveys; (iii) Daily timeframes; and (iv) Suggestions for future studies. Pilot ESM data demonstrates that there was fluctuation of depressive and anxiety symptoms within- and between- participants over the course of the study, however, greater sample power is needed for full analysis. This study demonstrated that ESM designs are feasible and acceptable among LGBTQ+ young people with current experiences of self-harm. Pilot data indicated that specific experiences and moods are likely to be important to self-harm. These potentially have a temporal influence on self-harm behaviour or ideation, and therefore should be examined in a fully powered sample.

20.
Diabetologia ; 54(1): 51-7, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20890591

RESUMEN

AIMS/HYPOTHESIS: Surveys in northern Ethiopia have demonstrated that apparent type 1 diabetes occurs more frequently than elsewhere in Africa and, indeed, in other parts of the world. We therefore investigated in detail a cohort of diabetic patients from this region to clarify the nature of this type of diabetes. METHODS: All patients attending the diabetic clinic at Mekelle Hospital in the Tigray region of northern Ethiopia were investigated over a 6 week period. Clinical, demographic and anthropometric data were collected, as well as measurements of HbA(1c), fasting lipid profile, fasting serum C-peptide and serum markers of beta cell autoimmunity, i.e. islet antigen-2 and GAD antibodies (GADA). RESULTS: Of 105 patients seen, 69 (66%) were on insulin treatment and had been from or close to diagnosis. Their median age and diabetes duration were 30 and 5 years, respectively, with a male excess of 2:1. Median BMI was 20.6 kg/m². Despite these clinical characteristics suggestive of type 1 diabetes, only 42 of 69 (61%) patients were C-peptide-negative and 35% GADA-positive. Overall, 38 (36%) of the total group (n = 105) had immunological or C-peptide characteristics inconsistent with typical type 1 or type 2 diabetes. The clinical characteristics, local prevalence of undernutrition, and GADA and C-peptide heterogeneity suggest a malnutrition-related form of diabetes. CONCLUSIONS/INTERPRETATION: Not all patients in northern Ethiopia with apparent type 1 diabetes appear to have the form of disease seen in Europids; their disease may, in fact, be related to malnutrition.


Asunto(s)
Péptido C/sangre , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 2/inmunología , Desnutrición/sangre , Desnutrición/inmunología , Adulto , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Etiopía , Femenino , Glutamato Descarboxilasa/inmunología , Humanos , Insulina/uso terapéutico , Masculino , Persona de Mediana Edad
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