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1.
Phys Rev Lett ; 129(17): 172701, 2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36332266

RESUMEN

The ß-delayed one- and two-neutron emission probabilities (P_{1n} and P_{2n}) of 20 neutron-rich nuclei with N≥82 have been measured at the RIBF facility of the RIKEN Nishina Center. P_{1n} of ^{130,131}Ag, ^{133,134}Cd, ^{135,136}In, and ^{138,139}Sn were determined for the first time, and stringent upper limits were placed on P_{2n} for nearly all cases. ß-delayed two-neutron emission (ß2n) was unambiguously identified in ^{133}Cd and ^{135,136}In, and their P_{2n} were measured. Weak ß2n was also detected from ^{137,138}Sn. Our results highlight the effect of the N=82 and Z=50 shell closures on ß-delayed neutron emission probability and provide stringent benchmarks for newly developed macroscopic-microscopic and self-consistent global models with the inclusion of a statistical treatment of neutron and γ emission. The impact of our measurements on r-process nucleosynthesis was studied in a neutron star merger scenario. Our P_{1n} and P_{2n} have a direct impact on the odd-even staggering of the final abundance, improving the agreement between calculated and observed Solar System abundances. The odd isotope fraction of Ba in r-process-enhanced (r-II) stars is also better reproduced using our new data.

2.
Am J Transplant ; 18(3): 696-703, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29087035

RESUMEN

Preliminary evidence suggests that postoperative cognitive dysfunction (POCD) is common after lung transplantation. The impact of POCD on clinical outcomes has yet to be studied. The association between POCD and longer-term survival was therefore examined in a pilot study of posttransplantation survivors. Forty-nine participants from a prior randomized clinical trial underwent a neurocognitive assessment battery pretransplantation and 6 months posttransplantation, including assessments of the domains of Executive Function (Trail Making Test, Stroop, Digit Span), Processing Speed (Ruff 2 and 7 Test, Digit Symbol Substitution Test), and Verbal Memory (Verbal Paired Associates, Logical Memory, Animal Naming, and Controlled Oral Word Association Test). During a 13-year follow-up, 33 (67%) participants died. Greater neurocognition was associated with longer survival (hazard ratio [HR] = 0.49 [0.25-0.96], P = .039), and this association was strongest on tests assessing Processing Speed (HR = 0.58 [0.36-0.95], P = .03) and Executive Function (HR = 0.52 [0.28-0.97], P = .040). In addition, unadjusted analyses suggested an association between greater Memory performance and lower risk of CLAD (HR = 0.54 [0.29-1.00], P = .050). Declines in Executive Function tended to be predictive of worse survival. These preliminary findings suggest that postoperative neurocognition is predictive of subsequent mortality among lung transplant recipients. Further research is needed to confirm these findings in a larger sample and to examine mechanisms responsible for this relationship.


Asunto(s)
Trastornos del Conocimiento/mortalidad , Rechazo de Injerto/mortalidad , Trasplante de Pulmón/efectos adversos , Complicaciones Posoperatorias , Calidad de Vida , Trastornos del Conocimiento/etiología , Femenino , Estudios de Seguimiento , Rechazo de Injerto/etiología , Supervivencia de Injerto , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Proyectos Piloto , Pronóstico , Factores de Riesgo , Tasa de Supervivencia
3.
Am J Transplant ; 16(1): 271-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26366639

RESUMEN

Lung transplantation has become an increasingly common treatment for patients with end-stage lung disease. Few studies have examined psychosocial risk factors for mortality in transplant recipients, despite evidence suggesting that elevated levels of negative affect are associated with greater mortality following major cardiac surgery. We therefore examined the relationship between negative affect early after lung transplantation and long-term survival in a sample of 132 lung transplant recipients (28 cystic fibrosis, 64 chronic obstructive pulmonary disease, 26 idiopathic pulmonary fibrosis, 14 other) followed for up to 13.5 years (median 7.4 years) following transplantation. Patients underwent both medical and psychosocial assessments 6 months following transplantation, which included the Beck Depression Inventory-II (BDI-II), Spielberger Anxiety Inventory, and General Health Questionnaire (GHQ). Over the course of follow-up, 80 (61%) participants died. Controlling for demographic factors, native lung disease, disease severity, family income, education level, social support, and frequency of posttransplant rejection, elevated symptoms of depression (BDI-II: HR = 1.31, p = 0.011) and distress (GHQ: HR = 1.28, p = 0.003) were associated with increased mortality. Higher levels of depression and general distress, but not anxiety, measured 6 months following lung transplantation are associated with increased mortality, independent of background characteristics and medical predictors.


Asunto(s)
Ansiedad/mortalidad , Trastorno Depresivo Mayor/mortalidad , Trasplante de Pulmón/psicología , Complicaciones Posoperatorias , Receptores de Trasplantes/psicología , Ansiedad/diagnóstico , Ansiedad/psicología , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/psicología , Femenino , Estudios de Seguimiento , Rechazo de Injerto , Supervivencia de Injerto , Humanos , Trasplante de Pulmón/efectos adversos , Trasplante de Pulmón/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo
4.
Soft Matter ; 12(20): 4530-6, 2016 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-27094902

RESUMEN

Dynamic control of the distribution of polystyrene suspended nanoparticles in evaporating droplets is investigated using a 2.9 µm high power laser. Under laser radiation a droplet is locally heated and fluid flows are induced that overcome the capillary flow, and thus a reversal of the coffee-stain effect is observed. Suspension particles are accumulated in a localised area, one order of magnitude smaller than the original droplet size. By scanning the laser beam over the droplet, particles can be deposited in an arbitrary pattern. This finding raises the possibility for direct laser writing of suspended particles through a liquid layer. Furthermore, a highly uniform coating is possible by manipulating the laser beam diameter and exposure time. The effect is expected to be universally applicable to aqueous solutions independent of solutes (either particles or molecules) and deposited substrates.

5.
BMC Infect Dis ; 16: 30, 2016 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-26818566

RESUMEN

BACKGROUND: Artemether-lumefantrine is currently the most widely recommended treatment of uncomplicated malaria. Lopinavir-based antiretroviral therapy is the commonly recommended second-line HIV treatment. Artemether and lumefantrine are metabolised by cytochrome P450 isoenzyme CYP3A4, which lopinavir/ritonavir inhibits, potentially causing clinically important drug-drug interactions. METHODS: An adaptive, parallel-design safety and pharmacokinetic study was conducted in HIV-infected (malaria-negative) patients: antiretroviral-naïve and those stable on lopinavir/ritonavir-based antiretrovirals. Both groups received the recommended six-dose artemether-lumefantrine treatment. The primary outcome was day-7 lumefantrine concentrations, as these correlate with antimalarial efficacy. Adverse events were solicited throughout the study, recording the onset, duration, severity, and relationship to artemether-lumefantrine. RESULTS: We enrolled 34 patients. Median day-7 lumefantrine concentrations were almost 10-fold higher in the lopinavir than the antiretroviral-naïve group [3170 versus 336 ng/mL; p = 0.0001], with AUC(0-inf) and Cmax increased five-fold [2478 versus 445 µg.h/mL; p = 0.0001], and three-fold [28.2 versus 8.8 µg/mL; p < 0.0001], respectively. Lumefantrine Cmax, and AUC(0-inf) increased significantly with mg/kg dose in the lopinavir, but not the antiretroviral-naïve group. While artemether exposure was similar between groups, Cmax and AUC(0-8h) of its active metabolite dihydroartemisinin were initially two-fold higher in the lopinavir group [p = 0.004 and p = 0.0013, respectively]. However, this difference was no longer apparent after the last artemether-lumefantrine dose. Within 21 days of starting artemether-lumefantrine there were similar numbers of treatment emergent adverse events (42 vs. 35) and adverse reactions (12 vs. 15, p = 0.21) in the lopinavir and antiretroviral-naïve groups, respectively. There were no serious adverse events and no difference in electrocardiographic QTcF- and PR-intervals, at the predicted lumefantrine Tmax. CONCLUSION: Despite substantially higher lumefantrine exposure, intensive monitoring in our relatively small study raised no safety concerns in HIV-infected patients stable on lopinavir-based antiretroviral therapy given the recommended artemether-lumefantrine dosage. Increased day-7 lumefantrine concentrations have been shown previously to reduce the risk of malaria treatment failure, but further evidence in adult patients co-infected with malaria and HIV is needed to assess the artemether-lumefantrine risk : benefit profile in this vulnerable population fully. Our antiretroviral-naïve patients confirmed previous findings that lumefantrine absorption is almost saturated at currently recommended doses, but this dose-limited absorption was overcome in the lopinavir group. TRIAL REGISTRATION: Clinical Trial Registration number NCT00869700. Registered on clinicaltrials.gov 25 March 2009.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Adulto , Fármacos Anti-VIH/efectos adversos , Fármacos Anti-VIH/farmacocinética , Arteméter , Artemisininas/efectos adversos , Artemisininas/farmacocinética , Artemisininas/uso terapéutico , Interacciones Farmacológicas , Etanolaminas/efectos adversos , Etanolaminas/farmacocinética , Etanolaminas/uso terapéutico , Femenino , Fluorenos/efectos adversos , Fluorenos/farmacocinética , Fluorenos/uso terapéutico , Infecciones por VIH/metabolismo , VIH-1/efectos de los fármacos , Humanos , Lopinavir/efectos adversos , Lopinavir/farmacocinética , Lopinavir/uso terapéutico , Lumefantrina , Masculino , Ritonavir/efectos adversos , Ritonavir/farmacocinética , Ritonavir/uso terapéutico
6.
Water Resour Res ; 51(7): 5531-5546, 2015 07.
Artículo en Inglés | MEDLINE | ID: mdl-26924859

RESUMEN

A generalized framework for discharge uncertainty estimation is presentedAllows estimation of place-specific discharge uncertainties for many catchmentsLocal conditions dominate in determining discharge uncertainty magnitudes.

7.
Cytopathology ; 25(2): 108-11, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23551700

RESUMEN

OBJECTIVES: Patients diagnosed with bladder carcinoma in situ (CIS) and treated with intravesical Bacillus Calmette-Guerin (BCG) often undergo post-induction random bladder biopsies to assess treatment response. We sought to determine the correlation between post-induction urinary cytology/cystoscopy and histopathological findings obtained by random bladder biopsies. METHODS: Patients who were treated with BCG between 2006 and 2010 for CIS, had surveillance cystoscopy and cytology, and subsequently underwent random bladder biopsies were selected for analysis. Patients with a history of or concomitant urothelial cell carcinoma (UCC) stage T1 or higher were excluded. Cystoscopic finings were characterized as follows: negative - no mucosal erythema, raised lesions or papillary tumours; suspicious - mucosal erythema, but no raised lesions or papillary tumours; and positive - sessile or papillary tumours. The accuracy of cytology in predicting the results of subsequent random bladder biopsies was analysed. RESULTS: Of 21 patients included, surveillance cystoscopy findings were characterized as negative in nine, suspicious in seven and positive in five. Of 16 patients with negative/suspicious cystoscopy, 13 had agreement between cytology and biopsy, nine of whom were negative and four positive. Three of 16 patients had positive cytology, but negative biopsies; on further investigation of these three, one had CIS and two subsequent UCC. In the positive cystoscopy group, four of five patients had agreement between cytology and biopsy, two of whom were negative and two positive. One of the five patients had negative cytology, but a positive biopsy. CONCLUSION: Our data suggest foregoing random bladder biopsies in patients with negative urine cytology and no evidence of intravesical recurrence on cystoscopy following an induction course of BCG for CIS of the urinary bladder.


Asunto(s)
Biopsia , Carcinoma in Situ/terapia , Citodiagnóstico/métodos , Vejiga Urinaria/patología , Adulto , Vacuna BCG/administración & dosificación , Carcinoma in Situ/patología , Cistoscopía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/patología
8.
Science ; 381(6660): 867-872, 2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37616348

RESUMEN

Coronal holes are areas on the Sun with open magnetic field lines. They are a source region of the solar wind, but how the wind emerges from coronal holes is not known. We observed a coronal hole using the Extreme Ultraviolet Imager on the Solar Orbiter spacecraft. We identified jets on scales of a few hundred kilometers, which last 20 to 100 seconds and reach speeds of ~100 kilometers per second. The jets are powered by magnetic reconnection and have kinetic energy in the picoflare range. They are intermittent but widespread within the observed coronal hole. We suggest that such picoflare jets could produce enough high-temperature plasma to sustain the solar wind and that the wind emerges from coronal holes as a highly intermittent outflow at small scales.

9.
Nat Commun ; 14(1): 2107, 2023 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-37055427

RESUMEN

Magnetic reconnection is a key mechanism involved in solar eruptions and is also a prime possibility to heat the low corona to millions of degrees. Here, we present ultra-high-resolution extreme ultraviolet observations of persistent null-point reconnection in the corona at a scale of about 390 km over one hour observations of the Extreme-Ultraviolet Imager on board Solar Orbiter spacecraft. The observations show formation of a null-point configuration above a minor positive polarity embedded within a region of dominant negative polarity near a sunspot. The gentle phase of the persistent null-point reconnection is evidenced by sustained point-like high-temperature plasma (about 10 MK) near the null-point and constant outflow blobs not only along the outer spine but also along the fan surface. The blobs appear at a higher frequency than previously observed with an average velocity of about 80 km s-1 and life-times of about 40 s. The null-point reconnection also occurs explosively but only for 4 minutes, its coupling with a mini-filament eruption generates a spiral jet. These results suggest that magnetic reconnection, at previously unresolved scales, proceeds continually in a gentle and/or explosive way to persistently transfer mass and energy to the overlying corona.

10.
Am J Transplant ; 12(9): 2519-25, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22548872

RESUMEN

Although neurocognitive impairment is relatively common among patients with advanced lung disease, little is known regarding changes in neurocognition following lung transplantation. We therefore administered 10 tests of neurocognitive functioning before and 6 months following lung transplantation and sought to identify predictors of change. Among the 49 study participants, native diseases included chronic obstructive pulmonary disease (n = 22), cystic fibrosis (n = 12), nonfibrotic diseases (n = 11) and other (n = 4). Although composite measures of executive function and verbal memory scores were generally within normal limits both before and after lung transplantation, verbal memory performance was slightly better posttransplant compared to baseline (p < 0.0001). Executive function scores improved in younger patients but worsened in older patients (p = 0.03). A minority subset of patients (29%) exhibited significant cognitive decline (i.e. >1 standard deviations on at least 20% of tests) from baseline to posttransplant. Patients who declined were older (p < 0.004) and tended to be less educated (p = 0.07). Lung transplantation, like cardiac revascularization procedures, appears to be associated with cognitive decline in a subset of older patients, which could impact daily functioning posttransplant.


Asunto(s)
Cognición , Enfermedades Pulmonares/cirugía , Trasplante de Pulmón , Adulto , Femenino , Humanos , Enfermedades Pulmonares/psicología , Masculino
11.
Mol Ecol ; 21(11): 2775-87, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22494503

RESUMEN

Repeated cycles of glaciation have had major impacts on the distribution of genetic diversity of the Antarctic marine fauna. During glacial periods, ice cover limited the amount of benthic habitat on the continental shelf. Conversely, more habitat and possibly altered seaways were available during interglacials when the ice receded and the sea level was higher. We used microsatellites and partial sequences of the mitochondrial cytochrome oxidase 1 gene to examine genetic structure in the direct-developing, endemic Southern Ocean octopod Pareledone turqueti sampled from a broad range of areas that circumvent Antarctica. We find that, unusually for a species with poor dispersal potential, P. turqueti has a circumpolar distribution and is also found off the islands of South Georgia and Shag Rocks. The overriding pattern of spatial genetic structure can be explained by hydrographic (with ocean currents both facilitating and hindering gene flow) and bathymetric features. The Antarctic Peninsula region displays a complex population structure, consistent with its varied topographic and oceanographic influences. Genetic similarities between the Ross and Weddell Seas, however, are interpreted as a persistent historic genetic signature of connectivity during the hypothesized Pleistocene West Antarctic Ice Sheet collapses. A calibrated molecular clock indicates two major lineages within P. turqueti, a continental lineage and a sub-Antarctic lineage, that diverged in the mid-Pliocene with no subsequent gene flow. Both lineages survived subsequent major glacial cycles. Our data are indicative of potential refugia at Shag Rocks and South Georgia and also around the Antarctic continent within the Ross Sea, Weddell Sea and off Adélie Land. The mean age of mtDNA diversity within these main continental lineages coincides with Pleistocene glacial cycles.


Asunto(s)
Variación Genética , Genética de Población , Octopodiformes/genética , Animales , Regiones Antárticas , ADN Mitocondrial , Ecosistema , Complejo IV de Transporte de Electrones/genética , Evolución Molecular , Flujo Génico , Cubierta de Hielo , Repeticiones de Microsatélite , Datos de Secuencia Molecular , Filogeografía
12.
Postgrad Med J ; 88(1035): 28-33, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22187490

RESUMEN

OBJECTIVE: To estimate the prevalence of, and implement a diagnostic strategy for, imported helminth infection in the gastroenterology clinic. DESIGN: A retrospective study of eosinophil count and probable tropical exposure (phase I) followed by a prospective study of parasitological investigation (phase II). SETTING: Gastroenterology service of an inner London hospital. PATIENTS: Adult patients newly attending general gastroenterology and inflammatory bowel disease clinics. INTERVENTIONS: In phase I, evidence of undiagnosed helminth infection was sought by analysing patient records for associations between eosinophil count and ethnicity. In phase II, a UK guideline for investigation of eosinophilia in migrants was implemented and diagnostic yield determined. MAIN OUTCOME MEASURES: In phase I, prevalence of eosinophilia was determined; in phase II, helminth prevalence and degree of eosinophilia before and after treatment were reported. Information on symptomatic response to treatment was recorded. Ethnicity was used as a proxy measure for tropical exposure. RESULTS: 426 new patients attended in a 12 month period. Eosinophilia was present in 27 (6.3%). 10/27 (37.0%) patients with eosinophilia were of African or Asian ethnicity whereas only 20% (85/426) of patients overall were from these ethnic groups (χ(2)=5.27, p=0.02). Following implementation of the protocol, 25/36 migrants with eosinophilia attended for parasitological investigations. Helminth infection was diagnosed in 10/25 (40%). Strongyloidiasis (six patients) and schistosomiasis (three patients) were the most common diagnoses. Median eosinophil count was 1.06×10(9)/l in those with helminths and 0.58×10(9)/l in those without (p=0.004). Eosinophil counts normalised in, and symptomatic improvement was reported by, most patients after treatment. CONCLUSIONS: Eosinophilia is associated with African or Asian ethnicity in an inner city gastroenterology service. This association is probably explained by imported helminths, which are prevalent in this setting, may be a cause of gastrointestinal symptoms and is easily diagnosed and treated by standard protocols.


Asunto(s)
Eosinofilia/epidemiología , Gastroenterología/estadística & datos numéricos , Helmintiasis/epidemiología , Parasitosis Intestinales/epidemiología , Migrantes , Adulto , África/etnología , Animales , Asia/etnología , Costo de Enfermedad , Eosinofilia/diagnóstico , Eosinofilia/etnología , Eosinófilos , Costos de la Atención en Salud/estadística & datos numéricos , Helmintiasis/diagnóstico , Helmintiasis/etnología , Humanos , Parasitosis Intestinales/diagnóstico , Parasitosis Intestinales/etnología , Londres/epidemiología , Servicio Ambulatorio en Hospital/estadística & datos numéricos , Prevalencia , Estudios Prospectivos , Estudios Retrospectivos , Migrantes/estadística & datos numéricos
13.
J Fish Biol ; 81(1): 253-69, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22747817

RESUMEN

This study investigated the biogeography and genetic variation in the antitropically distributed Micromesistius genus. A 579 bp fragment of the mitochondrial coI gene was analysed in 279 individuals of Micromesistius poutassou and 163 of Micromesistius australis. The time since divergence was estimated to be c. 2 million years before present (Mb.p.) with an externally derived clock rate by Bayesian methods. Congruent estimates were obtained with an additional data set of cytochrome b sequences derived from GenBank utilizing a different clock rate. The divergence time of 2 Mb.p. was in disagreement with fossil findings in New Zealand and previous hypotheses which suggested the divergence to be much older. It, therefore, appears likely that Micromesistius has penetrated into the southern hemisphere at least two times. Paleoceanographic records indicate that conditions that would increase the likelihood for transequatorial dispersals were evident c. 2-1·6 Mb.p.. Haplotype frequency differences, along with pairwise F(ST) values, indicated that Mediterranean M. poutassou is a genetically isolated population.


Asunto(s)
ADN Mitocondrial/genética , Gadiformes/genética , Variación Genética , Animales , Océano Atlántico , Teorema de Bayes , Evolución Molecular , Fósiles , Gadiformes/clasificación , Genética de Población , Haplotipos , Nueva Zelanda , Filogenia , Análisis de Secuencia de ADN , Especificidad de la Especie
14.
J Plast Reconstr Aesthet Surg ; 75(6): 1907-1915, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35153164

RESUMEN

INTRODUCTION: It is a long-established teaching to avoid operating on camptodactyly unless there is a failure of non-operative treatment, such as serial splinting and hand therapy, and there is an established proximal interphalangeal joint (PIPJ) contracture of 60°; a recent systematic review reflects this continuing approach, with some papers advocating intervention with a lesser degree of contracture. AIM: To evaluate whether early flexor digitorum superficialis (FDS) release, followed by gentle passive manipulation (GPM), will correct severe 'congenital' camptodactyly, if undertaken at an earlier age than usual, thus avoiding the more aggressive surgical approach required in the established adolescent cases. METHOD: The surgical technique and treatment algorithm are described. A multi-centre case series is presented; data analysis included patient demographics, syndromic association, side/digit affected, ages at onset, progression, referral and at surgery, operation details, pre- and post-operative contracture and range of motion. RESULTS: There were 12 patients (3 males, 9 females) who underwent 15 operations for 24 involved digits. Patients had surgery by 3 months (median) post-referral, and there was a significant improvement in median (range) PIPJ contracture (90°(30°-90°) vs. 0°(0°-45°); p<0.001) and range of motion (0°(0°-60°) vs. 90°(50°-95°); p<0.001), at a median post-operative follow-up of 2.5 years. According to the Siegert grade, 87.5% of digits had excellent/good post-operative outcomes and 12.5% had fair outcomes. CONCLUSION: This paper specifically addresses the problem of aggressive and progressive camptodactyly in the young child. By this, we mean patients who have failed non-operative treatment and have PIPJ contractures ≥60°, and those whose contractures have increased by 30° within 1 year. All cases responded to early FDS release and GPM, hence correcting the PIPJ contracture. However, cases with multiple digital involvement, whether syndromic or not, and failed previous surgery or the older child, required additional procedures to restore a dynamic dorsal apparatus and active extension.


Asunto(s)
Contractura , Articulaciones de los Dedos , Adolescente , Algoritmos , Niño , Contractura/cirugía , Femenino , Articulaciones de los Dedos/cirugía , Humanos , Masculino , Modalidades de Fisioterapia , Rango del Movimiento Articular
16.
Nat Med ; 2(4): 470-2, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8597961

RESUMEN

An acidic luminal pH (ref. 1-3) is involved in sperm maturation, and in maintaining sperm in an immotile state in the epididymis and vas deferens (2,4-6). Neutralization by prostatic fluid is one of a complex series of events that triggers sperm motility (2,7,8). Failure of the acidification mechanism might, therefore, result in poor sperm maturation, premature motility and infertility. We have shown that a vacuolar (H+)-ATPase is expressed at high levels on the luminal plasma membrane of specialized cells in the epididymis (9), which closely resemble acid-secreting kidney intercalated cells (10,11). We now show that similar cells are also present in the vas deferens, and that a bafilomycin-sensitive proton flux can be detected using a noninvasive proton-selective vibrating probe. Up to 80% of the net proton secretion in the vas deferens is inhibited by bafilomycin, consistent with a major role of a vacuolar-type (H+)-ATPase in this process. This acidification mechanism is a potential target for novel strategies aimed at modulating the acidification capacity of parts of the male reproductive tract and, therefore, in regulating male fertility.


Asunto(s)
Macrólidos , Bombas de Protones/fisiología , ATPasas de Translocación de Protón/fisiología , Maduración del Esperma , Conducto Deferente/fisiología , Animales , Antibacterianos/farmacología , Concentración de Iones de Hidrógeno , Masculino , Bombas de Protones/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
17.
J Fish Biol ; 78(1): 355-65, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21235567

RESUMEN

Although three species of the genus Macrourus are recognized in the Southern Ocean, DNA sequencing of the mitochondrial COI gene revealed four well-supported clades. These barcode data suggest the presence of an undescribed species, a conclusion supported by meristic and morphometric examination of specimens.


Asunto(s)
Código de Barras del ADN Taxonómico , Gadiformes/genética , Animales , Complejo IV de Transporte de Electrones/genética , Gadiformes/clasificación , Especificidad de la Especie
18.
Clin Nutr ESPEN ; 40: 282-287, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33183551

RESUMEN

INTRODUCTION: Decision-making regarding percutaneous endoscopic gastrostomy (PEG) insertion can be complex both medically and ethically. Thirty-day mortality following (PEG) insertion is an important quality indicator for endoscopy accreditation and for service evaluation. It also forms part of the measures assessed within the 'Getting It Right First Time' programme (GIRFT). We aimed to assess the impact of a newly adopted Feeding Issues MDT (FIMDT) and the clinical application of the Royal Free Gastrostomy Score (RFGS). METHOD: We adopted a retrospective observational methodology to assess the impact of a feeding issues MDT within our trust. The included study period ran from January 2016 to December 2019 (4 years). This formed part of a quality improvement (QI) project initiated upon receipt of the GIRFT report for our NHS trust. Statistical analysis and QI methodology was used to interpret and present the data. RESULTS: Two hundred and sixty eight PEG insertions occurred during the study period. 188 PEGs were inserted prior to the start of FIMDT and 45 following its inception. On average there were 66 PEGs performed per year. There was no significant difference in age for those undergoing PEG insertion pre (68 years) and post (69 years) FIMDT adoption. Prior to FIMDT those that died within 30 days post PEG were significantly older than those who did not (p < 0.001), whilst following FIMDT adoption there was no such difference. Prior to FIMDT the 30-day post PEG mortality was 10.64%, whilst following adoption of the FIMDT the mortality rate fell to 6.6% (p = 0.04). The mean number of procedures performed between a 30-day mortality occurring rose from 7.5 to 13.6. Furthermore, the mean number of days between a 30-day post insertion mortality occurring also rose from a mean of 53.0-111.8, pre and post FIMDT adoption. The Royal Free Gastrostomy Score (RFGS) for those discussed at FIMDT and declined for PEG insertion was significantly higher than those accepted for PEG insertion (p = 0.01). Over the entire study period those who died within 30 days following PEG insertion had a significantly greater RFGS (p < 0.0001). CONCLUSION: In our trust the adoption of a FIMDT has significantly reduced the 30-day mortality for PEG insertion. We have also demonstrated the clinical utility to assess mortality risk of the RFGS when making decisions around patient suitability for PEG insertion.


Asunto(s)
Endoscopía , Gastrostomía , Anciano , Humanos , Grupo de Atención al Paciente , Estudios Retrospectivos
19.
S Afr Med J ; 110(10): 1050-1055, 2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-33205738

RESUMEN

BACKGROUND: Young South Africans experience high rates of HIV infection. While nationally scaled medical male circumcision (MMC) can help to curb HIV infection rates in countries such as South Africa (SA), MMC uptake has not been consistent or universal, suggesting variable acceptability among men. Both MMC and traditional male circumcision (TMC) are practised in SA. For male circumcision to be most effective for HIV prevention, it should be performed prior to sexual debut with complete removal of the foreskin. OBJECTIVES: The MACHO (Male Adolescent Choices for HIV Prevention Options) study investigated uptake of and preference for MMC v. TMC in two culturally distinct settings in SA. METHODS: This observational, longitudinal, cohort study investigated circumcision preferences and uptake in 100 males (aged 14 - 17 years) and their legal guardians in Cape Town (Western Cape Province) and Soweto (Gauteng Province). Data were collected via surveys administered every 4 months over a 24-month period. RESULTS: A total of 100 uncircumcised adolescent boys (Cape Town n=50, Soweto n=50; mean (interquartile range) age 15 (14 - 16) years) and their guardians were enrolled. At baseline, 42 boys from Soweto (84%) and none from Cape Town expressed a preference for MMC over TMC. Sowetan participants were more likely to elect circumcision (MMC n=11 (22%), TMC n=1 (2%)) than those from Cape Town (TMC n=1 (2%), MMC n=0) over 13.6 months of follow-up (hazard ratio 18.9; 95% confidence interval 2.37 - 150.71; p=0.006). CONCLUSIONS: MMC was the preferred option for young men in Soweto compared with those in Cape Town, and this translated into practice. Despite knowledge of the benefits of early MMC, many participants delayed uptake, potentially reducing the MMC benefits before sexual debut. Programmes promoting circumcision should consider the influence of local practices. To realise full HIV prevention benefits, efforts should be made to ensure that circumcision is promoted, and that all circumcision is safe, performed prior to sexual debut, and contextually responsive.


Asunto(s)
Circuncisión Masculina/etnología , Circuncisión Masculina/estadística & datos numéricos , Infecciones por VIH/prevención & control , Aceptación de la Atención de Salud/etnología , Aceptación de la Atención de Salud/estadística & datos numéricos , Adolescente , Cultura , Utilización de Instalaciones y Servicios , Conocimientos, Actitudes y Práctica en Salud , Humanos , Estimación de Kaplan-Meier , Estudios Longitudinales , Masculino , Motivación , Utilización de Procedimientos y Técnicas , Modelos de Riesgos Proporcionales , Conducta Sexual , Enfermedades de Transmisión Sexual/prevención & control , Sudáfrica/epidemiología
20.
Dis Aquat Organ ; 86(2): 163-7, 2009 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-19902845

RESUMEN

Ciliates associated with fish mortalities in a New Zealand hatchery were identified by DNA sequencing of the small subunit ribosomal RNA gene (SSU rRNA). Tissue samples were taken from lesions and gill tissues on freshly dead juvenile groper, brain tissue from adult kingfish, and from ciliate cultures and rotifers derived from fish mortality events between January 2007 and March 2009. Different mortality events were characterized by either of 2 ciliate species, Uronema marinum and Miamiensis avidus. A third ciliate, Mesanophrys carcini, was identified in rotifers used as food for fish larvae. Sequencing part of the SSU rRNA provided a rapid tool for the identification and monitoring of scuticociliates in the hatchery and allowed the first identification of these species in farmed fish in New Zealand.


Asunto(s)
Infecciones por Cilióforos/veterinaria , Cilióforos/genética , Enfermedades de los Peces/parasitología , Explotaciones Pesqueras , Animales , Cilióforos/clasificación , Cilióforos/aislamiento & purificación , Infecciones por Cilióforos/epidemiología , Infecciones por Cilióforos/mortalidad , Infecciones por Cilióforos/parasitología , ADN Ribosómico/genética , Brotes de Enfermedades/veterinaria , Enfermedades de los Peces/epidemiología , Enfermedades de los Peces/mortalidad , Biología Marina , Datos de Secuencia Molecular , Nueva Zelanda/epidemiología , Filogenia , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
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