Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 107
Filtrar
1.
Phys Rev Lett ; 126(24): 242301, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34213947

RESUMO

Using combined data from the Relativistic Heavy Ion and Large Hadron Colliders, we constrain the shear and bulk viscosities of quark-gluon plasma (QGP) at temperatures of ∼150-350 MeV. We use Bayesian inference to translate experimental and theoretical uncertainties into probabilistic constraints for the viscosities. With Bayesian model averaging we propagate an estimate of the model uncertainty generated by the transition from hydrodynamics to hadron transport in the plasma's final evolution stage, providing the most reliable phenomenological constraints to date on the QGP viscosities.

2.
BMC Med ; 17(1): 219, 2019 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-31801542

RESUMO

BACKGROUND: In November 2011, Malawi introduced the 13-valent pneumococcal conjugate vaccine (PCV13) into the routine infant schedule. Four to 7 years after introduction (2015-2018), rolling prospective nasopharyngeal carriage surveys were performed in the city of Blantyre. Carriage of Streptococcus pneumoniae vaccine serotypes (VT) remained higher than reported in high-income countries, and impact was asymmetric across age groups. METHODS: A dynamic transmission model was fit to survey data using a Bayesian Markov-chain Monte Carlo approach, to obtain insights into the determinants of post-PCV13 age-specific VT carriage. RESULTS: Accumulation of naturally acquired immunity with age and age-specific transmission potential were both key to reproducing the observed data. VT carriage reduction peaked sequentially over time, earlier in younger and later in older age groups. Estimated vaccine efficacy (protection against carriage) was 66.87% (95% CI 50.49-82.26%), similar to previous estimates. Ten-year projected vaccine impact (VT carriage reduction) among 0-9 years old was lower than observed in other settings, at 76.23% (CI 95% 68.02-81.96%), with sensitivity analyses demonstrating this to be mainly driven by a high local force of infection. CONCLUSIONS: There are both vaccine-related and host-related determinants of post-PCV13 pneumococcal VT transmission in Blantyre with vaccine impact determined by an age-specific, local force of infection. These findings are likely to be generalisable to other Sub-Saharan African countries in which PCV impact on carriage (and therefore herd protection) has been lower than desired, and have implications for the interpretation of post-PCV carriage studies and future vaccination programs.


Assuntos
Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/uso terapêutico , Streptococcus pneumoniae/efeitos dos fármacos , Idoso , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Malaui , Masculino , Modelos Teóricos , Vacinas Pneumocócicas/farmacologia , Estudos Prospectivos
3.
Nanoscale ; 11(42): 19814-19822, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31624822

RESUMO

The emergence of ferroelectricity in nanometer-thick films of doped hafnium oxide (HfO2) makes this material a promising candidate for use in Si-compatible non-volatile memory devices. The switchable polarization of ferroelectric HfO2 controls functional properties of these devices through the electric potential distribution across the capacitor. The experimental characterization of the local electric potential at the nanoscale has not so far been realized in practice. Here, we develop a new methodology which allows us, for the first time, to experimentally quantify the polarization-dependent potential profile across few-nanometer-thick ferroelectric Hf0.5Zr0.5O2 thin films. Using a standing-wave excitation mode in synchrotron based hard X-ray photoemission spectroscopy, we depth-selectively probe TiN/Hf0.5Zr0.5O2/W prototype memory capacitors and determine the local electrostatic potential by analyzing the core-level line shifts. We find that the electric potential profile across the Hf0.5Zr0.5O2 layer is non-linear and changes with in situ polarization switching. Combined with our scanning transmission electron microscopy data and theoretical modeling, we interpret the observed non-linear potential behavior in terms of defects in Hf0.5Zr0.5O2, at both interfaces, and their charge state modulated by the ferroelectric polarization. Our results provide an important insight into the intrinsic electronic properties of HfO2 based ferroelectric capacitors and are essential for engineering memory devices.

4.
Vaccine ; 36(47): 7142-7148, 2018 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-29887320

RESUMO

INTRODUCTION: Despite increased use of vaccine in routine immunisation, rotavirus remains a major cause of acute gastroenteritis (AGE) in low-income countries. We describe rotavirus prevalence and hospitalisation in Malawi pre and four years post vaccine introduction; provide updated vaccine effectiveness (VE) estimates; and assess rotavirus vaccine indirect effects. METHODS: Children under five years of age presenting to a referral hospital in Blantyre with AGE were recruited. Stool samples were tested for rotavirus using Enzyme Immunoassay. The change in rotavirus prevalence was evaluated using Poisson regression. Time series analysis was used to further investigate trends in prevalence over time. VE against rotavirus diarrhoea of any severity was estimated using logistic regression. Indirect effects were estimated by evaluating rotavirus prevalence in unvaccinated children over time, and by comparing observed reductions in incidence of rotavirus hospitalisation to those expected based on vaccine coverage and trial efficacy estimates. RESULTS: 2320 children were included. Prevalence of rotavirus in hospitalised infants (<12 months) with AGE decreased from 69/139(49.64%) prior to vaccine introduction to 197/607(32.45%) post-vaccine introduction (adjusted RR 0.67[95% CI 0.55, 0.82]). Prevalence in children aged 12-23 months demonstrated a less substantial decline: 15/37(40.54%) pre- and 122/352(34.66%) post-vaccine introduction (adjusted RR 0.85, 95% CI 0.57, 1.28). Adjusted VE was 61.89%(95% CI 28.04-79.82), but lower in children aged 12-23 months (31.69% [95% CI -139.03 to 80.48]). In hospitalised infants with rotavirus disease, the observed overall effect of the vaccine was 9% greater than expected according to vaccine coverage and efficacy estimates. Rotavirus prevalence among unvaccinated infants declined post-vaccine introduction (RR 0.70[95% CI 0.55-0.80]). CONCLUSIONS: Following rotavirus vaccine introduction in Malawi, prevalence of rotavirus in hospitalised children with AGE has declined significantly, with some evidence of an indirect effect in infants. Despite this, rotavirus remains an important cause of severe diarrhoea in Malawian children, particularly in the second year of life.


Assuntos
Diarreia/prevenção & controle , Gastroenterite/prevenção & controle , Hospitalização/estatística & dados numéricos , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/uso terapêutico , Doença Aguda/epidemiologia , Diarreia/epidemiologia , Diarreia/virologia , Fezes/virologia , Feminino , Gastroenterite/epidemiologia , Gastroenterite/virologia , Humanos , Imunoensaio , Incidência , Lactente , Malaui/epidemiologia , Masculino , Distribuição de Poisson , Prevalência , Rotavirus/imunologia , Infecções por Rotavirus/epidemiologia , Fatores de Tempo , Cobertura Vacinal , Vacinas Atenuadas/uso terapêutico
5.
ACS Appl Mater Interfaces ; 10(13): 10607-10611, 2018 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-29558103

RESUMO

When pristine material surfaces are exposed to air, highly reactive broken bonds can promote the formation of surface oxides with structures and properties differing greatly from bulk. Determination of the oxide structure is often elusive through the use of indirect diffraction methods or techniques that probe only the outermost layer. As a result, surface oxides forming on widely used materials, such as group III-nitrides, have not been unambiguously resolved, even though critical properties can depend sensitively on their presence. In this study, aberration corrected scanning transmission electron microscopy reveals directly, and with depth dependence, the structure of ultrathin native oxides that form on AlN and GaN surfaces. Through atomic resolution imaging and spectroscopy, we show that the oxide layers are comprised of tetrahedra-octahedra cation-oxygen units, in an arrangement similar to bulk θ-Al2O3 and ß-Ga2O3. By applying density functional theory, we show that the observed structures are more stable than previously proposed surface oxide models. We place the impact of these observations in the context of key III-nitride growth, device issues, and the recent discovery of two-dimensional nitrides.

6.
Space Sci Rev ; 214(1)2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-30713357

RESUMO

OSIRIS-REx will return pristine samples of carbonaceous asteroid Bennu. This article describes how pristine was defined based on expectations of Bennu and on a realistic understanding of what is achievable with a constrained schedule and budget, and how that definition flowed to requirements and implementation. To return a pristine sample, the OSIRIS-REx spacecraft sampling hardware was maintained at level 100 A/2 and <180 ng/cm2 of amino acids and hydrazine on the sampler head through precision cleaning, control of materials, and vigilance. Contamination is further characterized via witness material exposed to the spacecraft assembly and testing environment as well as in space. This characterization provided knowledge of the expected background and will be used in conjunction with archived spacecraft components for comparison with the samples when they are delivered to Earth for analysis. Most of all, the cleanliness of the OSIRIS-REx spacecraft was achieved through communication among scientists, engineers, managers, and technicians.

7.
Nano Lett ; 17(10): 6248-6257, 2017 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-28876941

RESUMO

The epitaxial growth of multifunctional oxides on semiconductors has opened a pathway to introduce new functionalities to semiconductor device technologies. In particular, the integration of gate materials that enable nonvolatile or hysteretic functionality in field-effect transistors could lead to device technologies that consume less power or allow for novel modalities in computing. Here we present electrical characterization of ultrathin single crystalline SrZrxTi1-xO3 (x = 0.7) films epitaxially grown on a high mobility semiconductor, Ge. Epitaxial films of SrZrxTi1-xO3 exhibit relaxor behavior, characterized by a hysteretic polarization that can modulate the surface potential of Ge. We find that gate layers as thin as 5 nm corresponding to an equivalent-oxide thickness of just 1.0 nm exhibit a ∼2 V hysteretic window in the capacitance-voltage characteristics. The development of hysteretic metal-oxide-semiconductor capacitors with nanoscale gate thicknesses opens new vistas for nanoelectronic devices.

8.
ACS Appl Mater Interfaces ; 8(44): 30379-30386, 2016 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-27607060

RESUMO

Nanowires of electrochemically active electrode materials for lithium ion batteries represent a unique system that allows for intensive investigations of surface phenomena. In particular, highly ordered nanowire arrays produced by electrodeposition into anodic aluminum oxide templates can lead to new insights into a material's electrochemical performance by providing a high-surface-area electrode with negligible volume expansion induced pulverization. Here we show that for the Li-CuxSb ternary system, stabilizing the surface chemistry is the most critical factor for promoting long electrode life. The resulting solid electrolyte interphase is analyzed using a mix of electron microscopy, X-ray photoelectron spectroscopy, and lithium ion battery half-cell testing to provide a better understanding of the importance of electrolyte composition on this multicomponent alloy anode material.

9.
Insects ; 7(1)2016 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-26848691

RESUMO

Invertebrate diversity is important for a multitude of ecosystem services and as a component of the larger ecological food web. A better understanding of the factors influencing invertebrate taxonomic richness and diversity at both local and landscape scales is important for conserving biodiversity within the agricultural landscape. The aim of this study was to determine if invertebrate richness and diversity in agricultural field interiors and edges in central Illinois, USA, were related to the complexity of the surrounding landscape. Our results show taxonomic richness and diversity in field edges is positively related to large scale landscape complexity, but the relationship is negative for field interiors. These unexpected results need further study.

10.
J Cyst Fibros ; 14(2): 228-36, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25466700

RESUMO

RATIONALE: Airway inflammation is central to cystic fibrosis (CF) pathophysiology. Pre-clinical models have shown that phosphodiesterase inhibitors (PDEi) like sildenafil have anti-inflammatory activity. PDEi have not been studied in CF subjects. OBJECTIVES: We evaluated the pharmacokinetics, tolerability, and safety of sildenafil in subjects with CF. Sputum biomarkers were used to explore efficacy. METHODS: An open-label pilot study of oral sildenafil administration was conducted in adults with mild to moderate CF lung disease. Subjects received oral sildenafil 20 or 40 mg p.o. t.i.d. for 6 weeks. MEASUREMENTS AND MAIN RESULTS: Twenty subjects completed the study. Estimated elimination rate constants were statistically different in subjects with CF compared to previously published non-CF subjects. Side effects were generally mild. There were no drug-related serious adverse events. Sputum neutrophil elastase activity decreased. CONCLUSIONS: Subjects with CF may eliminate sildenafil at a faster rate than non-CF subjects. Sildenafil administration was safe in subjects with CF and decreased sputum elastase activity. Sildenafil warrants further study as an anti-inflammatory in CF.


Assuntos
Fibrose Cística , Elastase de Leucócito/metabolismo , Citrato de Sildenafila , Escarro/efeitos dos fármacos , Adulto , Biomarcadores/metabolismo , Fibrose Cística/tratamento farmacológico , Fibrose Cística/metabolismo , Fibrose Cística/fisiopatologia , Monitoramento de Medicamentos/métodos , Feminino , Humanos , Inflamação/tratamento farmacológico , Pulmão/metabolismo , Pulmão/fisiopatologia , Masculino , Inibidores da Fosfodiesterase 5/administração & dosagem , Inibidores da Fosfodiesterase 5/efeitos adversos , Inibidores da Fosfodiesterase 5/farmacocinética , Índice de Gravidade de Doença , Citrato de Sildenafila/administração & dosagem , Citrato de Sildenafila/efeitos adversos , Citrato de Sildenafila/farmacocinética , Escarro/metabolismo , Resultado do Tratamento
11.
J Food Sci ; 79(10): E2014-22, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25212592

RESUMO

The emulsifying properties of plant legume protein isolates (soy, pea, and lupin) were compared to a milk whey protein, ß-lactoglobulin (ß-lg), and a nonionic surfactant (Tween 20). The protein fractional composition was characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. The following emulsion properties were measured: particle diameter, shear surface ζ-potential, interfacial tension (IT), and creaming velocity. The effect of protein preheat treatment (90 °C for 10 min) on the emulsifying behavior and the release of selected volatile organic compounds (VOCs) from emulsions under oral conditions was also investigated in real time using proton transfer reaction-mass spectrometry. The legume proteins showed comparable results to ß-lg and Tween 20, forming stable, negatively charged emulsions with particle diameter d3,2 < 0.4 µm, and maintained stability over 50 d. The relatively lower stability of lupin emulsions was significantly correlated with the low protein surface hydrophobicity and IT of the emulsion. After heating the proteins, the droplet size of pea and lupin emulsions decreased. The VOC release profile was similar between the protein-stabilized emulsions, and greater retention was observed for Tween 20-stabilized emulsions. This study demonstrates the potential application of legume proteins as alternative emulsifiers to milk proteins in emulsion products.


Assuntos
Emulsões/química , Fabaceae/química , Lactoglobulinas/química , Óleos/química , Proteínas de Plantas/química , Polissorbatos/química , Eletroforese em Gel de Poliacrilamida , Emulsificantes/química , Compostos Orgânicos Voláteis
12.
Zookeys ; (344): 55-71, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24194660

RESUMO

A Ph.D. dissertation completed by E.D. Cashatt in 1968 entitled "Revision of the Chrysauginae of North America" does not meet the criteria of publication so the new taxa described therein are not available per the International Code of Zoological Nomenclature. In order to validate the taxa proposed in that document we formally describe and illustrate the following: Arta brevivalvalis Cashatt, sp. n., Heliades lindae Cashatt, sp. n., Paragalasa Cashatt, gen. n., Paragalasa exospinalis Cashatt, sp. n., and Penthesilea sacculalis baboquivariensis Cashatt, subsp. n. We summarize other taxonomic actions proposed in the dissertation and those proposed by subsequent authors. We provide the current nomenclatural status with the literature citation of the paper in which the current status was proposed. A lectotype is designated for Clydonopteran tecomae. Adult holotypes and associated labels, and genitalia of paratypes are newly illustrated.

13.
Food Chem ; 140(1-2): 124-34, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23578623

RESUMO

The relationship between emulsion structure and the release of volatile organic compounds (VOCs) was investigated using a model mouth system under oral conditions (tongue mastication, artificial saliva, pH and salt). The VOCs were monitored on-line by proton transfer reaction mass spectrometry (PTR-MS). Two types of emulsion system were compared: primary and multilayer oil-in-water (P-O/W, M-O/W) emulsions consisting of soy oil coated by ß-lactoglobulin and pectin layers. The P-O/W emulsions showed intensive flocculation at pH 5 and above 200 mM NaCl where the electrostatic repulsive charge was at a minimum. Bridging and depletion flocculation were mostly observed for P-O/W emulsions containing artificial saliva with 1 wt% mucin. The VOC release was found to increase when the emulsion droplets flocculated, thus changing the oil volume phase distribution. The adsorbed pectin layer stabilised the emulsion structure under conditions of short-time oral processing, and hindered the release of hydrophobic VOCs.


Assuntos
Lactoglobulinas/química , Lactoglobulinas/metabolismo , Boca/metabolismo , Compostos Orgânicos Voláteis/química , Emulsões/química , Emulsões/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Modelos Biológicos , Óleos/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Água/metabolismo
14.
West Indian med. j ; 61(8): 789-794, Nov. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-694342

RESUMO

OBJECTIVE: The aims of this study were to evaluate the effect of anticardiolipin antibody (aCL) and lupus anticoagulant (LA) on the outcome of the in vitro ferlitization (IVF) cycles and to determine the prevalence of these antibodies in infertile women seeking IVF in Jamaica. METHODS: A retrospective cohort study was performed to determine if screening patients for aCL and LA had any significant impact on the outcome of the IVF process. Each patient's hospital record, between March 2000 and March 2010, was collected and the relevant data extracted. RESULTS: The prevalence of aCL in this cohort of Jamaican women was moderate/high positive 3.88%, low positive 0.68% and those with negative aCL results 95.4%. The prevalence of women who were LA positive was 4.1% and 0.9% of the women were positive for both LA and aCL. Of the patients who were LA and/or aCL positive, eight out of 30 patients (26.7%) had a positive pregnancy test in comparison to 61 out of 181 patients (33.7%) who were LA and/or aCL negative (p = 0.5787). CONCLUSION: The prevalence of positive aCL and/or lA in infertile women seeking IVF in Jamaica is 7.76%. The presence of these antibodies did not affect the pregnancy rate of these women nor did it demonstrate an increased risk for IVF cycle cancellation or ovarian hyperstimulation syndrome. Screening women undergoing IVF for these antibodies is not justified.


OBJETIVO: Los objetivos de este estudio fueron evaluar el efecto del anticuerpo anticardiolipina (aCL) y el anticoagulante lúpico (LA) sobre el resultado de los ciclos de la fertilización en vitro (FIV), así como determinar la prevalencia de estos anticuerpos en mujeres estériles que buscan tratamiento de FIV en Jamaica. MÉTODOS: Se realizó un estudio de cohorte para determinar si el tamizaje de pacientes para detectar el anticuerpo anticardiolipina y el anticoagulante lúpico tenía un impacto significativo en el resultado del proceso de FIV. Se obtuvieron las historias clínicas hospitalarias de cada una de las pacientes, entre marzo de 2000 y marzo de 2010, y se extrajeron los datos pertinentes. RESULTADOS: La prevalencia de aCL en esta cohorte de mujeres jamaicanas fue 3.88% moderada/alta positiva, 0.68% positiva baja, y aquellas con resultados negativos de aCL, 95.4%. La prevalencia de mujeres con resultados de anticoagulante lúpico positivos fue 4.1%, y 0.9% de las mujeres resultaron positivas con respecto tanto al LA como al aCL. De las pacientes que fueron positivas al LA y/o al aCL, ocho de cada 30 pacientes (26.7%) tuvieron una prueba de embarazo positiva, en comparación con 61 de cada 181 pacientes (33.7%) negativas al LA y/o al aCL (p = 0.5787). CONCLUSIÓN: La prevalencia de resultados positivos en relación con anticuerpos anticardiolipinas y/o anticoagulantes lúpicos en mujeres estériles que buscan FIV en Jamaica es 7.76%. La presencia de estos anticuerpos no afectó la tasa de embarazo de estas mujeres, ni mostró un aumento de riesgo de la cancelación del ciclo FIV, o riesgo de síndrome de hiperestimulación ovárica. El tamizaje en busca de estos anticuerpos en mujeres que buscan tratamiento de FIV, no está justificado.


Assuntos
Adulto , Feminino , Humanos , Gravidez , Anticorpos Anticardiolipina/sangue , Infertilidade Feminina/sangue , Inibidor de Coagulação do Lúpus/sangue , Fertilização in vitro , Jamaica , Taxa de Gravidez , Estudos Retrospectivos
15.
J Agric Food Chem ; 60(39): 9918-27, 2012 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-22957471

RESUMO

The release of volatile organic compounds (VOCs) into the mouth cavity is an integral part of the way flavor is perceived. An in vitro model mouth with an artificial tongue was developed to measure the dynamic release of VOCs from liquid model systems [e.g., aqueous solution, oil, and oil-in-water (O/W) emulsions] under oral conditions. The release of seven selected VOCs was affected by the different polarity and vapor pressure of the compounds and their affinity to the liquid system media. Different tongue pressure patterns were applied to the liquid systems, and the release of VOCs was monitored in real time using proton transfer reaction-mass spectrometry. The release was significantly more intense for longer tongue pressure duration and was influenced by the tongue altering the sample surface area and the distribution of the VOCs. The role of saliva (artificial versus human) and the sample temperature had a significant effect on VOC release. Saliva containing mucin and a higher sample temperature enhanced the release.


Assuntos
Boca/metabolismo , Língua/química , Compostos Orgânicos Voláteis/metabolismo , Humanos , Modelos Teóricos , Paladar , Temperatura , Língua/metabolismo
16.
West Indian Med J ; 61(8): 789-94, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23757899

RESUMO

OBJECTIVE: The aims of this study were to evaluate the effect of anticardiolipin antibody (aCL) and lupus anticoagulant (LA) on the outcome of the in vitro ferlitization (IVF) cycles and to determine the prevalence of these antibodies in infertile women seeking IVF in Jamaica. METHODS: A retrospective cohort study was performed to determine if screening patients for aCL and LA had any significant impact on the outcome of the IVF process. Each patients hospital record, between March 2000 and March 2010, was collected and the relevant data extracted. RESULTS: The prevalence of aCL in this cohort of Jamaican women was moderate/high positive 3.88%, low positive 0.68% and those with negative aCL results 95.4%. The prevalence of women who were LA positive was 4.1% and 0.9% of the women were positive for both LA and aCL. Of the patients who were LA and/or aCL positive, eight out of 30 patients (26.7%) had a positive pregnancy test in comparison to 61 out of 181 patients (33.7%) who were LA and/or aCL negative (p = 0.5787). CONCLUSION: The prevalence of positive aCL and/or LA in infertile women seeking IVF in Jamaica is 7.76%. The presence of these antibodies did not affect the pregnancy rate of these women nor did it demonstrate an increased risk for IVF cycle cancellation or ovarian hyperstimulation syndrome. Screening women undergoing IVF for these antibodies is not justified.


Assuntos
Anticorpos Anticardiolipina/sangue , Infertilidade Feminina/sangue , Inibidor de Coagulação do Lúpus/sangue , Adulto , Feminino , Fertilização in vitro , Humanos , Jamaica , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
17.
West Indian Med J ; 60(1): 41-5, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21809710

RESUMO

OBJECTIVE: To examine the impact of intracytoplasmic sperm injection (ICSI) on the treatment of subfertile couples in Jamaica. METHOD: A review of the outcome of treatment cycles for infertile couples that underwent in-vitro fertilisation (IVF) and ICSI from 2003-05 at the Hugh Wynter Fertility Management Unit (HWFMU) of the University of the West Indies. Fertilisation and pregnancy rates for the cycles as well as the factors determining the success of the procedure were reviewed. SPSS 11.1 was used to do statistical calculations. RESULTS: Ninety-six ICSI cycles were done from January 1, 2003 to December 31, 2005. For couples with previous poor or no fertilisation in a standard IVF group (n = 12), the fertilisation rate was 72%; for those with substandard semen (n = 73), the fertilisation rate was 77.5%, for those with semen retrieved by surgical sperm method (n = 11), the fertilisation rate was 59%. The resulting live births were 0%, 12.5% and 27.3% respectively. There was a statistically significant impact of age on pregnancy rates as the mean age of the females in the previously poor or no fertilisation in a standard IVF group (39.08 +/- 5.14) was greater than those of the substandard semen group (35.93 +/- 4.22) [p = 0.023] as well as the group with surgical sperm retrieval (32.82 +/- 6.65) [p = 0.019]. CONCLUSION: With ICSI, the fertilisation and pregnancy rates in Jamaica are comparable to international rates regardless of the cause of infertility. However, the age of the female partner does have a significant impact on the pregnancy rate following ICSI.


Assuntos
Infertilidade Masculina/terapia , Injeções de Esperma Intracitoplásmicas , Adulto , Fatores Etários , Análise de Variância , Transferência Embrionária , Feminino , Fertilização in vitro , Humanos , Jamaica , Masculino , Gravidez , Estudos Retrospectivos , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Resultado do Tratamento
18.
West Indian med. j ; 60(1): 42-46, Jan. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-672715

RESUMO

OBJECTIVES: To examine the impact of intracytoplasmic sperm injection (ICSI) on the treatment of subfertile couples in Jamaica. METHOD: A review of the outcome of treatment cycles for infertile couples that underwent in-vitro fertilisation (IVF) and ICSI from 2003-05 at the Hugh Wynter Fertility Management Unit (HWFMU) of the University of the West Indies. Fertilisation and pregnancy rates for the cycles as well as the factors determining the success of the procedure were reviewed. SPSS 11.1 was used to do statistical calculations. RESULTS: Ninety-six ICSI cycles were done from January 1, 2003 to December 31, 2005. For couples with previous poor or no fertilisation in a standard IVF group (n = 12), the fertilisation rate was 72%; for those with substandard semen (n = 73), the fertilisation rate was 77.5%, for those with semen retrieved by surgical sperm method (n = 11), the fertilisation rate was 59%. The resulting live births were 0%, 12.5% and 27.3% respectively. There was a statistically significant impact ofage on pregnancy rates as the mean age ofthe females in the previously poor or no fertilisation in a standard IVF group (39.08 ± 5.14) was greater than those of the substandard semen group (35.93 ± 4.22) ]p = 0.023[ as well as the group with surgical sperm retrieval (32.82 ± 6.65) ]p = 0.019[. CONCLUSION: With ICSI, the fertilisation and pregnancy rates in Jamaica are comparable to international rates regardless of the cause of infertility. However, the age of the female partner does have a significant impact on the pregnancy rate following ICSI.


OBJETIVO: Examinar el impacto de la inyección de esperma intracitoplasmático (IEIC) en el tratamiento de las parejas subfértiles en Jamaica. MÉTODO: Se realizó un examen del resultado de los ciclos de tratamiento para las parejas infértiles que recurrieron a la fertilización in vitro (FIV) y a la IEIC de 2003 a 2005 en la Unidad de Tratamiento de la Fertilidad Hugh Wynter del Hospital Universitario de West Indies (HWFMU). Se examinaron las tasas de fertilización y embarazos en todos los ciclos así como los factores que determinan el éxito del procedimiento. Se usó el programa SPSS para realizar los cálculos estadísticos. RESULTADOS: Se realizaron noventa y seis ciclos de IEIC del 1ero de enero de 2003, al 31 de diciembre de 2005. Para parejas con ninguna o pobre fertilización en un grupo estándar de FIV (n - 12), la tasa de fertilización fue 72%; para aquellos con semen subestándar (n = 73), la tasa de fertilización fue 77.5%; para aquellos con semen recuperado mediante recuperación quirúrgica de esperma (n = 11), la tasa de fertilización fue 59%. Los nacimientos vivos resultantes fueron 0%, 12.5%, y 27.3% respectivamente. Hubo un impacto estadísticamente significativo de la edad sobre las tasas de comembarazo, ya que la edad promedio de las hembras en la fertilización previamente pobre o sin fertilización en un grupo FIV estándar (39.08 ± 5.14) fue mayor para las del grupo de semen subestándar (35.93 ± 4.22) ]p = 0.023[ así como las del grupo con recuperación quirúrgica del esperma (32.82 ± 6.65) ]p = 0.019[. CONCLUSIÓN: Con el uso de IEIC, las tasas de fertilización y embarazo en Jamaica, son comparables a las tasas internacionales, independientemente de cual sea la causa de la infertilidad. Sin embargo, la edad de la pareja hembra no tiene un impacto significativo sobre la tasa de embarazo una vez aplicada la IEIC.


Assuntos
Adulto , Feminino , Humanos , Masculino , Gravidez , Infertilidade Masculina/terapia , Injeções de Esperma Intracitoplásmicas , Fatores Etários , Análise de Variância , Transferência Embrionária , Fertilização in vitro , Jamaica , Estudos Retrospectivos , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Resultado do Tratamento
19.
Sex Transm Infect ; 85(5): 370-5, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19473997

RESUMO

OBJECTIVES: To determine prevalence of, and risk factors for, bacterial vaginosis (BV) among herpes simplex virus (HSV) 2 seropositive Tanzanian women at enrollment into a randomised, placebo-controlled trial of HSV suppressive treatment. METHODS: 1305 HSV-2 seropositive women aged 16-35 years working in bars, guesthouses and similar facilities were interviewed, examined and tested for HIV, syphilis, Neisseria gonorrhoeae, Chlamydia trachomatis, BV, candidiasis and trichomoniasis. Factors associated with BV were analysed using logistic regression to estimate odds ratios and 95% confidence intervals. RESULTS: BV prevalence was 62.9%; prevalence of Nugent score 9-10 was 16.1%. Independent risk factors for BV were work facility type, fewer dependents, increasing alcohol consumption, sex in the last week (adjusted OR 2.03; 95% CI 1.57 to 2.62), using cloths or cotton wool for menstrual hygiene, HIV (adjusted OR 1.41; 95% CI 1.09 to 1.83) and Trichomonas vaginalis infection. There was no association between BV and the frequency or method of vaginal cleansing. However, BV was less prevalent among women who reported inserting substances to dry the vagina for sex (adjusted OR 0.44; 95% CI 0.25 to 0.75). CONCLUSION: BV was extremely prevalent among our study population of HSV-2 positive female facility workers in North-western Tanzania. Although recent sex was associated with increased BV prevalence, vaginal drying was associated with lower BV prevalence. Further studies of the effects of specific practices on vaginal flora are warranted.


Assuntos
Herpesvirus Humano 2/imunologia , Vagina/microbiologia , Vaginose Bacteriana/epidemiologia , Adolescente , Adulto , Animais , Chlamydia trachomatis/isolamento & purificação , Feminino , Gonorreia/epidemiologia , Infecções por HIV/epidemiologia , HIV-1/isolamento & purificação , Humanos , Prevalência , Fatores de Risco , Comportamento Sexual , Sífilis/epidemiologia , Tanzânia/epidemiologia , Tricomoníase/epidemiologia , Trichomonas vaginalis/isolamento & purificação , Ducha Vaginal , Adulto Jovem
20.
Thorax ; 64(7): 626-30, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19359269

RESUMO

BACKGROUND: Measures of oxygenation have not been assessed for prognostic significance in systemic sclerosis-related interstitial lung disease (SSc-ILD). METHODS: 83 subjects with SSc-ILD performed a maximal cardiopulmonary exercise test with an arterial line. The agreement between peripheral oxygen saturation (SpO2) and arterial oxygen saturation (SaO2) was examined and survival differences between subgroups of subjects stratified on SpO2 were analysed. Cox proportional hazards analyses were used to examine the prognostic capabilities of SpO2. RESULTS: At maximal exercise the mean (SD) difference between SpO2 and SaO2 was 2.98 (2.98) and only 15 subjects had a difference of >4 points. The survival of subjects with SSc-ILD whose maximum exercise SpO2 (Spo(2)max) fell below 89% or whose SpO2max fell >4 points from baseline was worse than subjects in comparator groups (log rank p = 0.01 and 0.01, respectively). The hazard of death during the median 7.1 years of follow-up was 2.4 times greater for subjects whose SpO2max fell below 89% (hazard ratio 2.4, 95% CI 1.1 to 4.9, p = 0.02) or whose SpO2max fell >4 points from baseline (hazard ratio 2.4, 95% CI 1.1 to 5.0, p = 0.02). CONCLUSION: In patients with SSc-ILD, SpO2 is an adequate reflection of SaO2 and radial arterial lines need not be inserted during cardiopulmonary exercise tests in these patients. Given the ease of measurement and its prognostic value, SpO2 should be considered as a meaningful clinical and research outcome in patients with SSc-ILD.


Assuntos
Exercício Físico/fisiologia , Oxigênio/sangue , Escleroderma Sistêmico/sangue , Adulto , Teste de Esforço , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Prognóstico , Escleroderma Sistêmico/fisiopatologia , Análise de Sobrevida
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...