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1.
PeerJ ; 12: e17018, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38618571

RESUMEN

The African leopard (Panthera pardus pardus) has lost a significant proportion of its historical range, notably in north-western Africa and South Africa. Recent studies have explored the genetic diversity and population structure of African leopards across the continent. A notable genetic observation is the presence of two divergent mitochondrial lineages, PAR-I and PAR-II. Both lineages appeared to be distributed widely, with PAR-II frequently found in southern Africa. Until now, no study has attempted to date the emergence of either lineage, assess haplotype distribution, or explore their evolutionary histories in any detail. To investigate these underappreciated questions, we compiled the largest and most geographically representative leopard data set of the mitochondrial NADH-5 gene to date. We combined samples (n = 33) collected in an altitudinal transect across the Mpumalanga province of South Africa, where two populations of leopard are known to be in genetic contact, with previously published sequences of African leopard (n = 211). We estimate that the maternal PAR-I and PAR-II lineages diverged approximately 0.7051 (0.4477-0.9632) million years ago (Ma). Through spatial and demographic analyses, we show that while PAR-I underwent a mid-Pleistocene population expansion resulting in several closely related haplotypes with little geographic structure across much of its range, PAR-II remained at constant size and may even have declined slightly in the last 0.1 Ma. The higher genetic drift experienced within PAR-II drove a greater degree of structure with little haplotype sharing and unique haplotypes in central Africa, the Cape, KwaZulu-Natal and the South African Highveld. The phylogeographic structure of PAR-II, with its increasing frequency southward and its exclusive occurrence in south-eastern South Africa, suggests that this lineage may have been isolated in South Africa during the mid-Pleistocene. This hypothesis is supported by historical changes in paleoclimate that promoted intense aridification around the Limpopo Basin between 1.0-0.6 Ma, potentially reducing gene flow and promoting genetic drift. Interestingly, we ascertained that the two nuclear DNA populations identified by a previous study as East and West Mpumalanga correspond to PAR-I and PAR-II, respectively, and that they have come into secondary contact in the Lowveld region of South Africa. Our results suggest a subdivision of African leopard mtDNA into two clades, with one occurring almost exclusively in South Africa, and we identify the potential environmental drivers of this observed structure. We caution that our results are based on a single mtDNA locus, but it nevertheless provides a hypothesis that can be further tested with a dense sample of nuclear DNA data, preferably whole genomes. If our interpretation holds true, it would provide the first genetic explanation for the smaller observed size of leopards at the southernmost end of their range in Africa.


Asunto(s)
Panthera , Animales , Panthera/genética , Sudáfrica , Evolución Biológica , Flujo Genético , ADN Mitocondrial/genética
2.
Sci Immunol ; 9(91): eadi2848, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38277466

RESUMEN

Psoriasis vulgaris and other chronic inflammatory diseases improve markedly with therapeutic blockade of interleukin-23 (IL-23) signaling, but the genetic mechanisms underlying clinical responses remain poorly understood. Using single-cell transcriptomics, we profiled immune cells isolated from lesional psoriatic skin before and during IL-23 blockade. In clinically responsive patients, a psoriatic transcriptional signature in skin-resident memory T cells was strongly attenuated. In contrast, poorly responsive patients were distinguished by persistent activation of IL-17-producing T (T17) cells, a mechanism distinct from alternative cytokine signaling or resistance isolated to epidermal keratinocytes. Even in IL-23 blockade-responsive patients, we detected a recurring set of recalcitrant, disease-specific transcriptional abnormalities. This irreversible immunological state may necessitate ongoing IL-23 inhibition. Spatial transcriptomic analyses also suggested that successful IL-23 blockade requires dampening of >90% of IL-17-induced response in lymphocyte-adjacent keratinocytes, an unexpectedly high threshold. Collectively, our data establish a patient-level paradigm for dissecting responses to immunomodulatory treatments.


Asunto(s)
Interleucina-17 , Psoriasis , Humanos , Interleucina-23 , Piel , Psoriasis/tratamiento farmacológico , Queratinocitos
3.
Neurosci Lett ; 818: 137556, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37951300

RESUMEN

ADHD is a neurocognitive disorder characterized by attention difficulties, hyperactivity, and impulsivity, often persisting into adulthood with substantial personal and societal consequences. Despite the importance of neurophysiological assessment and treatment monitoring tests, their availability outside of research settings remains limited. Cognitive neuroscience investigations have identified distinct components associated with ADHD, including deficits in sustained attention, inefficient enhancement of attended Targets, and altered suppression of ignored Distractors. In this study, we examined pupil activity in control and ADHD subjects during a sustained visual attention task specifically designed to evaluate the mechanisms underlying Target enhancement and Distractor suppression. Our findings revealed some distinguishing factors between the two groups which we discuss in light of their neurobiological implications.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Humanos , Trastorno por Déficit de Atención con Hiperactividad/psicología , Dilatación , Conducta Impulsiva , Agitación Psicomotora
4.
Aorta (Stamford) ; 10(3): 114-121, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36318932

RESUMEN

BACKGROUND: Open surgical repair (OSR) of complex abdominal aortic aneurysms (CAAAs) can be challenging. We frequently utilize the retroperitoneal (RP) approach for such cases. We audited our outcomes with the aim of establishing the utility and safety of this approach. METHODS: Retrospective analysis was performed of all patients undergoing OSR of an unruptured CAAA via a RP approach in our center over a 7-year period. Data on repairs via a transperitoneal (TP) approach were collected to provide context. Demographic, operative, radiological, and biochemical data were collected. The primary outcome measure was 30-day/inpatient mortality. Secondary outcomes included the need for reoperation, incidence of postoperative chest infection, acute kidney injury (AKI) and length of stay (LOS). All patients received aortic clamping above at least one main renal artery. RESULTS: One hundred and three patients underwent OSR of an unruptured CAAA; 55 via a RP approach, 48 TP. The RP group demonstrated a more advanced pattern of disease with a larger median maximum diameter (65 vs. 61 mm, p= 0.013) and a more proximal extent. Consequently, the rate of supravisceral clamping was higher in RP repair (66 vs. 15%, p < 0.001). Despite this there were no differences in the observed early mortality (9.1 vs. 10%, NS); incidence of reoperation (10.9 vs. 12.5%, NS), chest infection (32.7 vs. 25%, NS), and AKI (52.7 vs. 45.8%, NS); or median LOS (10 vs. 12 days, NS) following RP and TP repair. CONCLUSION: OSR of CAAAs carries significant 30-day mortality. In patients unsuitable for fenestrated endovascular aortic repair or those desiring a durable long-term solution, OSR can be performed through the RP or TP approach. This study has demonstrated that in our unit RP repair facilitates treatment of more advanced AAA utilizing complex proximal clamp zones with similar perioperative morbidity and mortality compared with TP cases utilizing more distal clamping.

5.
Eur J Trauma Emerg Surg ; 48(3): 2003-2012, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33884449

RESUMEN

INTRODUCTION: Emergency laparotomy is a considerable component of a colorectal surgeon's workload and conveys substantial morbidity and mortality, particularly in older patients. Frailty is associated with poorer surgical outcomes. Frailty and sarcopenia assessment using Computed Tomography (CT) calculation of psoas major area predicts outcomes in elective and emergency surgery. Current risk predictors do not incorporate frailty metrics. We investigated whether sarcopenia measurement enhanced mortality prediction in over-65 s who underwent emergency laparotomy and emergency colorectal resection. METHODS: An analysis of data collected prospectively during the National Emergency Laparotomy Audit (NELA) was conducted. Psoas major (PM) cross-sectional area was measured at the L3 level and a ratio of PM to L3 vertebral body area (PML3) was calculated. Outcome measures included inpatient, 30-day and 90-day mortality. Statistical analysis was conducted using Mann-Whitney, Chi-squared and receiver operating characteristics (ROC). Logistic regression was conducted using P-POSSUM variables with and without the addition of PML3. RESULTS: Nine-hundred and forty-four over-65 s underwent emergency laparotomy from three United Kingdom hospitals were included. Median age was 76 years (IQR 70-82 years). Inpatient mortality was 21.9%, 30-day mortality was 16.3% and 90-day mortality was 20.7%. PML3 less than 0.39 for males and 0.31 for females indicated significantly worse outcomes (inpatient mortality 68% vs 5.6%, 30-day mortality 50.6% vs 4.0%,90-day mortality 64% vs 5.2%, p < 0.0001). PML3 was independently associated with mortality in multivariate analysis (p < 0.0001). Addition of PML3 to P-POSSUM variables improved area under the curve (AUC) on ROC analysis for inpatient mortality (P-POSSUM:0.78 vs P-POSSUM + PML3:0.917), 30-day mortality(P-POSSUM:0.802 vs P-POSSUM + PML3: 0.91) and 90-day mortality (P-POSSUM:0.79 vs P-POSSUM + PML3: 0.91). CONCLUSION: PML3 is an accurate predictor of mortality in over-65 s undergoing emergency laparotomy. Addition of PML3 to POSSUM appears to improve mortality risk prediction.


Asunto(s)
Neoplasias Colorrectales , Fragilidad , Sarcopenia , Anciano , Neoplasias Colorrectales/complicaciones , Estudios Transversales , Urgencias Médicas , Femenino , Fragilidad/complicaciones , Humanos , Laparotomía , Masculino , Estudios Retrospectivos , Medición de Riesgo , Sarcopenia/diagnóstico por imagen
6.
Sci Rep ; 11(1): 5960, 2021 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-33727580

RESUMEN

This study aimed to consolidate current knowledge of wildlife brucellosis in Africa and to analyse available predictors of infection. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Information on species, test used, test results, area, rainfall, livestock and wildlife contact and year of study were extracted. This systematic review revealed 42 prevalence studies, nine disease control articles and six articles on epidemiology. Brucella abortus, Brucella melitensis, Brucella inopinata and Brucella suis were reported in wildlife. The prevalence studies revealed serological evidence of brucellosis in buffalo, antelope (positive in 14/28 species), carnivores (4/12) and other species (7/20) over the last five decades. Buffalo populations were more likely to be infected and had a higher seroprevalence than other species; the pooled seroprevalence was 13.7% (95% CI 10.3-17.3%) in buffalo, 7.1% (95% CI 1.1-15.5%) in carnivores and 2.1% (95% CI 0.1-4.9%) in antelope. Wildlife in high rainfall areas (≥ 800 mm) were more likely to be infected, and infected populations showed higher seroprevalence in high rainfall areas and in studies published after 2000. Domestic animal contact was associated with increased seroprevalence in antelope and carnivore species, but not in buffalo, supporting the hypothesis that buffalo may be a reservoir species.


Asunto(s)
Enfermedades de los Animales/epidemiología , Enfermedades de los Animales/microbiología , Animales Salvajes , Brucella , Brucelosis/veterinaria , África/epidemiología , Enfermedades de los Animales/transmisión , Animales , Vectores Arácnidos/microbiología , Estudios Transversales , Interacciones Huésped-Patógeno , Análisis Multivariante , Vigilancia en Salud Pública , Estudios Seroepidemiológicos , Garrapatas/microbiología , Zoonosis
7.
Int J Colorectal Dis ; 35(6): 1095-1102, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32215679

RESUMEN

INTRODUCTION: Sarcopenia is associated with outcomes in older-adults undergoing emergency surgery. Psoas major measurement is a surrogate marker of sarcopenia with multiple calculations existing normalising to body size and no consensus as to which is optimal. We compared three different psoas-major calculations to predict outcomes in older adults undergoing emergency laparotomy. METHODS: Consecutive over 65s were identified from the National Emergency Laparotomy Audit(NELA) database at a single centre between 2014 and 2018. Psoas major was measured at the L3 level and normalised to height (psoas muscle index, PMI), L3 vertebral body (psoas muscle:L3 ratio, PML3) or body surface area (psoas:body surface area, PBSA) and each correlated to outcomes. Outcome measures included inpatient, 30-day and 90-day mortality. A comparison of the three calculations was performed using the Mann-Whitney U, chi-squared, receiver operating characteristic curves (ROC) and binary logistic regression. RESULTS: Two hundred and sixty-four older adults underwent emergency laparotomy (median age, 75 years ((IQR, 70-81 years), 50% female)). Inpatient mortality was 19.6%, 30-day mortality was 15.1% and 90-day mortality was 18.5%. A total of 31.1% of males and 30% of females were sarcopenic (30.6% overall). A multivariate analysis confirmed each method of psoas major calculation (p < 0.0001) to be associated with mortality, as was ASA-grade (p < 0.0001). Area under the curve (AUC) was greatest for PML3 in predicting mortality (inpatient: PML3, 0.76; PMI, 0.71; PBSA, 0.70; 30-day: PML3, 0.74; PMI, 0.68; PBSA, 0.68; and 90-day: PML3, 0.78; PMI, 0.71; PBSA, 0.70). ASA-grade, P-POSSUM and PML3 were independently associated with mortality on multivariate analysis. ROC analysis of predictions from logistic regression models demonstrated PML3 to be more closely aligned to mortality than ASA or P-POSSUM (inpatient: AUC:PML3, 0.807; ASA, 0.783; P-POSSUM, 0.762; 30-day:AUC: PML3, 0.799; ASA, 0.784; P-POSSUM, 0.787; and 90-day: AUC:PML3, 0.805; ASA, 0.781; P-POSSUM, 0.756). CONCLUSIONS: Sarcopenia was present in 30.6% of older adults undergoing emergency surgery and is associated with a significantly increased mortality. PML3 is superior to PMI or PBSA and should be considered the method of calculation of choice. Additionally, PML3 compares favourably to ASA and P-POSSUM.


Asunto(s)
Enfermedades Intestinales/cirugía , Músculos Psoas/diagnóstico por imagen , Sarcopenia/diagnóstico por imagen , Sarcopenia/mortalidad , Tomografía Computarizada por Rayos X , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Estatura , Superficie Corporal , Urgencias Médicas , Femenino , Indicadores de Salud , Mortalidad Hospitalaria , Humanos , Enfermedades Intestinales/complicaciones , Estimación de Kaplan-Meier , Vértebras Lumbares/diagnóstico por imagen , Masculino , Tamaño de los Órganos , Periodo Preoperatorio , Músculos Psoas/patología , Curva ROC , Estudios Retrospectivos , Medición de Riesgo/métodos , Sarcopenia/complicaciones , Sarcopenia/patología , Reino Unido/epidemiología
8.
Bull Menninger Clin ; 84(2): 105-136, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31967511

RESUMEN

Anxiety disorders are commonly comorbid in adolescents and young adults with high-functioning autism. Cognitive-behavioral treatments (CBT) for anxiety, when adapted and expanded to target autism spectrum disorder (ASD) characteristics, may be beneficial, but there is minimal evidence to guide clinicians in their application. This multiple-baseline design study evaluated the initial efficacy of a CBT protocol adapted to address anxiety symptoms and adaptive functioning in this population. Anxiety and ASD symptoms were assessed for six participants at intake, after baseline, posttreatment, and at 1-month follow-up. Parent- and child-reported anxiety was also assessed during baseline and treatment. Visual inspection and reliable change index scores were used to evaluate change. All participants improved on clinician-rated measures of disorder severity, and gains were maintained at follow-up. Results were more equivocal for parent- and self-rated anxiety and parent-rated ASD, partly because of spontaneous changes during baseline.


Asunto(s)
Trastornos de Ansiedad/complicaciones , Trastornos de Ansiedad/terapia , Trastorno del Espectro Autista/complicaciones , Trastorno del Espectro Autista/psicología , Terapia Cognitivo-Conductual/métodos , Adolescente , Adulto , Trastornos de Ansiedad/psicología , Femenino , Humanos , Masculino , Proyectos Piloto , Resultado del Tratamiento , Adulto Joven
9.
Eur J Trauma Emerg Surg ; 46(1): 215-220, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30317377

RESUMEN

INTRODUCTION: Emergency laparotomy in patients over the age of 80 is associated with high morbidity and mortality. Accurate risk prediction in this patient population is desirable. Sarcopenia has been shown to be associated with outcome in multiple clinical settings and the psoas major muscle as measured on computed tomography (CT) imaging has been demonstrated as a marker of sarcopenia. We aim to assess the use of psoas major measurement on pre-operative CT as a prognostic indicator in over-80s undergoing emergency laparotomy and compare this measurement to P-POSSUM. METHODS: A retrospective interrogation of the prospectively collected National Emergency Laparotomy Database including all over-80s undergoing emergency laparotomy between January 2014 and September 2016 was conducted. Demographic, operative data and P-POSSUM data were collected and analysed. Computed tomography (CT) images were accessed and analysed, and cross-sectional areas of psoas major and the corresponding lumbar vertebral body at the level of the L3 inferior end plate were calculated. The ratio of psoas major-to-L3 cross-sectional area (PM:L3) was calculated for each patient. Mann-Whitney U test and receiver-operating characteristics (ROC) curves were used for statistical analysis. RESULTS: One hundred and three over-80s underwent emergency laparotomy. Male:female ratio was 60:43. Median age was 84 years (range 80-98 years). 30-day mortality was 19.4%.90-day mortality was 25.2%. Median PM:L3 ratio in patients who died as an inpatient was 0.3 and PM:L3 ratio in patients who survived to discharge was 0.52 (p < 0.0001). Median PM:L3 ratio in patient who died within 30 days post-op was 0.28 and 0.48 in those patients who survived to 30 days (p < 0.0001). Median PM:L3 ratio in patient who died within 90 days post-op was 0.28 and 0.51 in those patients who survived to 90 days (p < 0.0001). ROC analysis gave an area under the curve (AUC) of 0.85 for in-patient mortality, 0.86 for 30-day mortality, and 0.88 for 90-day mortality. ROC analysis for P-POSSUM in this data set demonstrated an AUC of 0.51 for in-patient mortality and 0.75 for 30- and 90-day mortality. CONCLUSION: CT imaging of the abdomen and pelvis is routinely used in over-80s prior to emergency laparotomy making PM:L3 calculation feasible for the majority of patients in this group. PM:L3 ratio is a useful prognostic indicator for prediction of mortality in patients over the age of 80. PM:L3 is superior to the P-POSSUM score in this series.


Asunto(s)
Urgencias Médicas , Mortalidad Hospitalaria , Obstrucción Intestinal/cirugía , Perforación Intestinal/cirugía , Laparotomía , Vértebras Lumbares/diagnóstico por imagen , Músculos Psoas/diagnóstico por imagen , Sarcopenia/diagnóstico por imagen , Anciano de 80 o más Años , Enfermedades del Colon/cirugía , Enfermedades Duodenales/cirugía , Femenino , Hemorragia/cirugía , Humanos , Vértebras Lumbares/anatomía & histología , Masculino , Isquemia Mesentérica/cirugía , Mortalidad , Tamaño de los Órganos , Pronóstico , Músculos Psoas/anatomía & histología , Estudios Retrospectivos , Medición de Riesgo , Sarcopenia/epidemiología , Tomografía Computarizada por Rayos X
10.
Vector Borne Zoonotic Dis ; 20(4): 258-267, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31841655

RESUMEN

A cross sectional sero-epidemiological study was conducted on cattle in a communal farming area adjacent to Kruger National Park at a wildlife-livestock interface in South Africa. A total of 184 cattle were screened for exposure to 5 abortifacient or zoonotic pathogens, namely Coxiella burnetii, Toxoplasma gondii, Chlamydophila abortus, Neospora caninum, and Rift Valley fever virus (RVFV) using enzyme-linked immunosorbent assays. In addition, the virus neutralization test was used to confirm the presence of antibodies to RVFV. The seroprevalence of C. burnetii, T. gondii, C. abortus, N. caninum, and RVFV antibodies was 38.0%, 32.6%, 20.7%, 1.6%, and 0.5%, respectively, and varied between locations (p < 0.001). Seroprevalence of C. burnetii and T. gondii was highly clustered by location (intraclass correlation coefficient [ICC] = 0.57), and that of C. abortus moderately so (ICC = 0.11). Seroprevalence was not associated with sex or age for any pathogen, except for C. abortus, for which seroprevalence was positively associated with age (p = 0.01). The predominant mixed infections were C. burnetii and T. gondii (15.2%) and C. burnetii, T. gondii, and C. abortus (13.0%). The serological detection of the five abortifacient pathogens in cattle indicates the potential for economic losses to livestock farmers, health impacts to domestic animals, transmission across the livestock-wildlife interface, and the risk of zoonotic transmission. This is the first documentation of T. gondii infection in cattle in South Africa, while exposure to C. burnetii, C. abortus, and N. caninum infections is being reported for the first time in cattle in a wildlife-livestock interface in the country.


Asunto(s)
Aborto Veterinario/microbiología , Animales Salvajes , Enfermedades de los Bovinos/microbiología , Zoonosis , Aborto Veterinario/epidemiología , Envejecimiento , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/parasitología , Estudios Transversales , Femenino , Masculino , Estudios Seroepidemiológicos , Pruebas Serológicas , Sudáfrica/epidemiología
11.
Zoonoses Public Health ; 66(5): 458-469, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30859717

RESUMEN

Endemic zoonoses, such as Q fever and spotted fever group (SFG) rickettsiosis, are prevalent in South Africa, yet often undiagnosed. In this study, we reviewed the demographics and animal exposure history of patients presenting with acute febrile illness to community health clinics in Mpumalanga Province to identify trends and risk factors associated with exposure to Coxiella burnetii, the causative agent of Q fever, and infection by SFG Rickettsia spp. Clinical and serological data and questionnaires elucidating exposure to animals and their products were obtained from 141 acutely febrile patients between 2012 and 2016. Exposure or infection status to C. burnetii and SFG Rickettsia spp. was determined by presence of IgG or IgM antibodies. Logistic regression models were built for risk factor analysis. Clinical presentation of patients infected by SFG rickettsiosis was described. There were 37/139 (27%) patients with a positive C. burnetii serology, indicative of Q fever exposure. Patients who had reported attending cattle inspection facilities ("dip tanks") were 9.39 times more likely to be exposed to Q fever (95% CI: 2.9-30.4). Exposure risk also increased with age (OR: 1.03, 95% CI: 1.002-1.06). Twenty-one per cent of febrile patients (24/118) had evidence of acute infection by SFG Rickettsia spp. Similarly, attending cattle inspection facilities was the most significant risk factor (OR: 8.48, 95% CI: 1.58-45.60). Seropositivity of females showed a significant OR of 8.0 when compared to males (95% CI: 1.49-43.0), and consumption of livestock was associated with a decreased risk (OR: 0.02, 95% CI: 0.001-0.54). A trend between domestic cat contact and SFG rickettsiosis was also noted, albeit borderline non-significant. In this endemic region of South Africa, an understanding of risk factors for zoonotic pathogens, including exposure to domestic animals, can help clinic staff with diagnosis and appropriate therapeutic management of acutely febrile patients as well as identify target areas for education and prevention strategies.


Asunto(s)
Infecciones Bacterianas/epidemiología , Infecciones Bacterianas/microbiología , Fiebre Botonosa/epidemiología , Fiebre Q/epidemiología , Zoonosis/epidemiología , Zoonosis/microbiología , Enfermedad Aguda , Adulto , Animales , Fiebre Botonosa/microbiología , Coxiella burnetii , Femenino , Fiebre , Humanos , Masculino , Persona de Mediana Edad , Fiebre Q/microbiología , Rickettsia conorii , Factores de Riesgo , Estudios Seroepidemiológicos , Sudáfrica/epidemiología , Encuestas y Cuestionarios
12.
JAAD Case Rep ; 5(3): 293-295, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30891485
13.
J S Afr Vet Assoc ; 89(0): e1-e7, 2018 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-29781672

RESUMEN

Brucellosis is of worldwide economic and public health importance. Heifer vaccination with live attenuated Brucella abortus strain 19 (S19) is the cornerstone of control in low- and middle-income countries. Antibody persistence induced by S19 is directly correlated with the number of colony-forming units (CFU) per dose. There are two vaccination methods: a 'high' dose (5-8 × 1010 CFU) subcutaneously injected or one or two 'low' doses (5 × 109 CFU) through the conjunctival route. This study aimed to evaluate serological reactions to the 'high' dose and possible implications of the serological findings on disease control. This study included 58 female cases, vaccinated at Day 0, and 29 male controls. Serum was drawn repeatedly and tested for Brucella antibodies using the Rose Bengal Test (RBT) and an indirect enzyme-linked immunosorbent assay (iELISA). The cases showed a rapid antibody response with peak RBT positivity (98%) at 2 weeks and iELISA (95%) at 8 weeks, then decreased in an inverse logistic curve to 14% RBT and 32% iELISA positive at 59 weeks and at 4.5 years 57% (4/7 cases) demonstrated a persistent immune response (RBT, iELISA or Brucellin skin test) to Brucella spp. Our study is the first of its kind documenting the persistence of antibodies in an African communal farming setting for over a year to years after 'high' dose S19 vaccination, which can be difficult to differentiate from a response to infection with wild-type B. abortus. A recommendation could be using a 'low' dose or different route of vaccination.


Asunto(s)
Vacuna contra la Brucelosis/inmunología , Brucella abortus/inmunología , Brucelosis Bovina/inmunología , Crianza de Animales Domésticos , Animales , Anticuerpos Antibacterianos/sangre , Vacuna contra la Brucelosis/administración & dosificación , Brucelosis Bovina/sangre , Brucelosis Bovina/microbiología , Brucelosis Bovina/prevención & control , Estudios de Casos y Controles , Bovinos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Estudios Longitudinales , Masculino , Sudáfrica
14.
Vector Borne Zoonotic Dis ; 18(6): 303-310, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29664701

RESUMEN

A lack of surveillance and diagnostics for zoonotic diseases in rural human clinics limits clinical awareness of these diseases. We assessed the prevalence of nine zoonotic pathogens in a pastoral, low-income, HIV-endemic community bordering wildlife reserves in South Africa. Two groups of participants were included: malaria-negative acute febrile illness (AFI) patients, called febrilers, at three clinics (n = 74) and second, farmers, herders, and veterinary staff found at five government cattle dip-tanks, called dip-tanksters (n = 64). Blood samples were tested using one PCR (Bartonella spp.) and eight antibody-ELISAs, and questionnaires were conducted to assess risk factors. Seventy-seven percent of febrilers and 98% of dip-tanksters had at least one positive test. Bartonella spp. (PCR 9.5%), spotted fever group (SFG) Rickettsia spp. (IgM 24.1%), Coxiella burnetii. (IgM 2.3%), and Leptospira spp. (IgM 6.8%) were present in febrilers and could have been the cause of their fever. Dip-tanksters and febrilers had evidence of past infection to Rickettsia spp. (IgG 92.2% and 63.4%, respectively) and C. burnetii (IgG 60.9% and 37.8%, respectively). No Brucella infection or current Bartonella infection was found in the dip-tanksters, although they had higher levels of recent exposure to Leptospira spp. (IgM 21.9%) compared to the febrilers. Low levels of West Nile and Sindbis, and no Rift Valley fever virus exposure were found in either groups. The only risk factor found to be significant was attending dip-tanks in febrilers for Q fever (p = 0.007). Amoxicillin is the local standard treatment for AFI, but would not be effective for Bartonella spp. infections, SFG rickettsiosis, Q fever infections, or the viral infections. There is a need to revise AFI treatment algorithms, educate medical and veterinary staff about these pathogens, especially SFG rickettsiosis and Q fever, support disease surveillance systems, and inform the population about reducing tick and surface water contact.


Asunto(s)
Animales Salvajes , Infecciones Bacterianas/microbiología , Ganado , Virosis/virología , Zoonosis/epidemiología , Zoonosis/microbiología , Adulto , Animales , Infecciones Bacterianas/epidemiología , Agricultores , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Sudáfrica/epidemiología , Garrapatas , Veterinarios , Virosis/epidemiología
15.
Trop Anim Health Prod ; 50(4): 903-906, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29274056

RESUMEN

This study shows the absence of the world's most common bacterial zoonoses caused by Brucella abortus and Brucella melitensis in cattle, goats and dogs in an agro-pastoral community in South Africa, where heifer vaccination against brucellosis with the live Strain 19 vaccine is compulsory. The study site is bordering wildlife reserves with multiple wildlife species infected with brucellosis. The results showed a low seroprevalence (1.4%) in cattle. Seroprevalence in cattle decreased with age after 4 years in females, males were less positive than females and a tissue culture from a brucellin skin test-positive male was negative. The results indicate that Brucella seropositivity in cattle is due to S19 vaccination and not natural infections. This conclusion is reinforced by the absence of Brucella seropositivity in goats (1/593 positive result) and dogs (0/315), which can be seen as potential spillover hosts. Therefore, the close proximity of brucellosis-infected wildlife is not a threat to domestic animals in this controlled setting with vaccination, fencing and movement control.


Asunto(s)
Brucelosis Bovina/epidemiología , Animales , Animales Domésticos , Animales Salvajes , Brucella abortus/aislamiento & purificación , Brucella melitensis/aislamiento & purificación , Brucelosis/epidemiología , Brucelosis/veterinaria , Bovinos , Estudios Transversales , Enfermedades de los Perros , Perros , Femenino , Cabras , Masculino , Salud Única , Población Rural , Estudios Seroepidemiológicos , Sudáfrica/epidemiología , Vacunación/veterinaria , Zoonosis/epidemiología
16.
PLoS One ; 12(11): e0184183, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29112947

RESUMEN

Carbon-carbon bond formation is one of the most challenging reactions in synthetic organic chemistry, and aldol reactions catalysed by dihydroxyacetone phosphate-dependent aldolases provide a powerful biocatalytic tool for combining C-C bond formation with the generation of two new stereo-centres, with access to all four possible stereoisomers of a compound. Dihydroxyacetone phosphate (DHAP) is unstable so the provision of DHAP for DHAP-dependent aldolases in biocatalytic processes remains complicated. Our research has investigated the efficiency of several different enzymatic cascades for the conversion of glycerol to DHAP, including characterising new candidate enzymes for some of the reaction steps. The most efficient cascade for DHAP production, comprising a one-pot four-enzyme reaction with glycerol kinase, acetate kinase, glycerophosphate oxidase and catalase, was coupled with a DHAP-dependent fructose-1,6-biphosphate aldolase enzyme to demonstrate the production of several rare chiral sugars. The limitation of batch biocatalysis for these reactions and the potential for improvement using kinetic modelling and flow biocatalysis systems is discussed.


Asunto(s)
Acetato Quinasa/metabolismo , Catalasa/metabolismo , Dihidroxiacetona Fosfato/metabolismo , Glicerol Quinasa/metabolismo , Glicerolfosfato Deshidrogenasa/metabolismo , Azúcares/síntesis química , Biocatálisis , Cromatografía Líquida de Alta Presión , Estereoisomerismo , Azúcares/química
17.
J S Afr Vet Assoc ; 88(0): e1-e7, 2017 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-29041786

RESUMEN

Dogs (Canis familiaris) are often free-roaming in sub-Saharan African countries. Rabies virus circulates in many of these populations and presents a public health issue. Mass vaccination of dog populations is the recommended method to decrease the number of dog and human rabies cases. We describe and compare four populations of dogs and their vaccination coverage in four different villages (Hluvukani, Athol, Utah and Dixie) in Bushbuckridge Municipality, Mpumalanga province, South Africa. Cross-sectional surveys were conducted in the villages of Athol, Utah and Dixie, while data from a Health and Demographic Surveillance System were used to describe the dog population in Hluvukani village. All households of the villages were visited to obtain information on the number, sex, age and rabies vaccination status of dogs. From May to October 2013, 2969 households were visited in the four villages and 942 owned dogs were reported. The populations were all young and skewed towards males. No differences were observed in the sex and age distributions (puppies 0-3 months excluded) among the villages. Athol had a higher proportion of dog-owning households than Hluvukani and Utah. Vaccination coverages were all above the 20% - 40% threshold required for herd immunity to rabies (38% in Hluvukani, 51% in Athol, 65% in Dixie and 74% in Utah). For the preparation of vaccination campaigns, we recommend the use of the relatively stable dog:human ratio (between 1:12 and 1:16) to estimate the number of dogs per village in Bushbuckridge Municipality.


Asunto(s)
Enfermedades de los Perros/epidemiología , Composición Familiar , Rabia/veterinaria , Vacunación/veterinaria , Animales , Estudios Transversales , Enfermedades de los Perros/prevención & control , Perros , Femenino , Humanos , Masculino , Propiedad , Pobreza , Rabia/epidemiología , Rabia/prevención & control , Vacunas Antirrábicas/provisión & distribución , Población Rural , Sudáfrica/epidemiología , Encuestas y Cuestionarios , Vacunación/estadística & datos numéricos
18.
Vaccine ; 35(31): 3844-3849, 2017 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-28602607

RESUMEN

Evidence suggests that rabies vaccine may have non-specific protective effects in animals and children. We analyzed four years of data (2012-2015) from an observational study of the health and demographics of a population of owned, free-roaming dogs in a low-income community in South Africa. The objective of this analysis was to assess the association between rabies vaccine and all-cause mortality in dogs, stratified by age group (0-3months, 4-11months, and 12months and older), and controlling for the effects of sex and number of dogs in the residence. Rabies vaccination reduced the risk of death from any cause by 56% (95% CI=16-77%) in dogs aged 0-3months, by 44% (95% CI=21-60%) in dogs aged 4-11months and by 16% (95% CI=0-29%) in dogs aged 12months and older. We hypothesize that the protective association between rabies vaccination status and all-cause mortality is due to a protective effect of rabies vaccine against diseases other than rabies. Existence of a strong non-specific protective effect of rabies vaccine on mortality in dogs would have implications for the design of dog rabies control programs that aim to eliminate dog-mediated human rabies cases. Further, we propose that owned domestic dogs in high mortality settings provide a useful animal model to better understand any non-specific protective effect of rabies vaccine in children, due to dogs' high numbers, high morbidity and mortality rates, relatively short lifespan, exposure to a variety of infectious and parasitic diseases, and shared environment with people.


Asunto(s)
Enfermedades de los Perros/mortalidad , Vacunas Antirrábicas/administración & dosificación , Factores de Edad , Animales , Perros , Femenino , Masculino , Sudáfrica , Análisis de Supervivencia
19.
J Clin Child Adolesc Psychol ; 46(6): 895-902, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-26467101

RESUMEN

Although behavioral parent training is considered efficacious treatment for childhood conduct problems, not all families benefit equally from treatment. Some parents take longer to change their behaviors and others ultimately drop out. Understanding how therapist behaviors impact parental engagement is necessary to improve treatment utilization. This study investigated how different techniques of therapist in vivo feedback (i.e., coaching) influenced parent attrition and skill acquisition in parent-child interaction therapy (PCIT). Participants included 51 parent-child dyads who participated in PCIT. Children (age: M = 5.03, SD = 1.65) were predominately minorities (63% White Hispanic, 16% African American or Black). Eight families discontinued treatment prematurely. Therapist coaching techniques during the first session of treatment were coded using the Therapist-Parent Interaction Coding System, and parent behaviors were coded with the Dyadic Parent-Child Interaction Coding System, Third Edition. Parents who received more responsive coaching acquired child-centered parenting skills more quickly. Therapists used fewer responsive techniques and more drills with families who dropped out of treatment. A composite of therapist behaviors accurately predicted treatment completion for 86% of families. Although group membership was correctly classified for the treatment completers, only 1 dropout was accurately predicted. Findings suggest that therapist in vivo feedback techniques may impact parents' success in PCIT and that responsive coaching may be particularly relevant.


Asunto(s)
Terapia Conductista/métodos , Conducta Infantil/psicología , Relaciones Padres-Hijo , Responsabilidad Parental/psicología , Preescolar , Femenino , Humanos , Masculino , Tutoría , Resultado del Tratamiento
20.
Cortex ; 82: 100-118, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27372902

RESUMEN

Efficient self-regulation of alertness declines with age exacerbating normal declines in performance across multiple cognitive domains, including learning and skill acquisition. Previous cognitive intervention studies have shown that it is possible to enhance alertness in patients with acquired brain injury and marked attention impairments, and that this benefit generalizes to improvements in more global cognitive functions. In the current preliminary studies, we sought to test whether this approach, that targets both tonic (over a period of minutes) and phasic (moment-to-moment) alertness, can improve key executive functioning declines in older adults, and enhance the rate of skill acquisition. The results of both Experiments 1 and 2 demonstrate that, compared to active control (AC) training, alertness training significantly enhanced performance in several validated executive function measures. In Experiment 2, alertness training significantly improved skill acquisition compared to AC training in a well-characterized speed of processing (SOP) task, with the largest benefits shown in the most challenging SOP blocks. The results of the current study suggest that targeting intrinsic alertness through cognitive training provides a novel approach to improve executive functions in older adults and may be a useful adjunct treatment to enhance benefits gained in other clinically validated treatments.


Asunto(s)
Envejecimiento/psicología , Cognición/fisiología , Función Ejecutiva/fisiología , Aprendizaje/fisiología , Práctica Psicológica , Anciano , Anciano de 80 o más Años , Atención/fisiología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas
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