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1.
Public Health ; 219: 131-138, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37167643

RESUMO

OBJECTIVES: 'Overweight and obesity' is the second biggest preventable cause of cancer after smoking. In 2018, Cancer Research UK launched an awareness raising campaign about the link between overweight and obesity and cancer risk. This study aimed to evaluate the reach and impact of the campaign. STUDY DESIGN: This study was a repeated cross-sectional online survey. METHODS: The campaign consisted of six elements including the main message that 'Obesity is a cause of cancer'. UK adults and Members of Parliament (MPs) were surveyed before the campaign (W1; n = 2124 and n = 151), 1 month (W2; n = 2050 and n = 151) and 3 months after the campaign (W3; n = 2059 and MPs not surveyed). Outcome measures were campaign reach, awareness of overweight and obesity as risk factors for cancer, attitudes towards individuals who are overweight or obese, support for policies to reduce obesity and reactions to the campaign. RESULTS: Overall, 76.2% of MPs and just under half of the public (47.5% in W2 and 36.8% in W3) reported having seen the campaign. Unprompted awareness of obesity as a risk factor increased among the public from 17.1% at W1 to 43.3% in W2 (odds ratio 3.71, 95% confidence interval 3.18-4.33) and 30.3% in W3 (odds ratio 2.11, 95% confidence interval 1.80-2.47). A similar pattern was seen for prompted awareness and among MPs. There were no consistent changes in attitudes towards overweight individuals or support for policies to reduce obesity. CONCLUSIONS: This evaluation suggests that the campaign achieved the primary objective of increasing awareness of the link between obesity and cancer without increasing negative attitudes towards individuals who are overweight or obese.


Assuntos
Neoplasias , Sobrepeso , Adulto , Humanos , Estudos Transversais , Obesidade/complicações , Obesidade/epidemiologia , Neoplasias/epidemiologia , Neoplasias/etiologia , Neoplasias/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Reino Unido/epidemiologia , Promoção da Saúde
2.
J Am Board Fam Med ; 34(Suppl): S192-S195, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33622837

RESUMO

AIMS: We hypothesized that glycemic control in outpatients, measured by HbA1c, was worse during the early months of the COVID-19 pandemic than in 2019. We sought to quantify how much worse and to determine if social determinants of health were associated with these differences. MATERIALS AND METHODS: Data were extracted from the electronic medical records of 2 cohorts of patients seen in the family medicine clinic of a southeastern academic health center. Three hundred patients with baseline HbA1c results as well as HbA1c results in May 2019 or May 2020 were evaluated. RESULTS: The groups had similar mean baseline HbA1c (7.65, SD = 1.50 for 2019; 7.61, SD = 1.71 for 2020; P = .85). Mean May HbA1c decreased from baseline in 2019 (7.19, SD = 1.45) but rose in 2020 (7.63, SD = 1.73), a statistically significant difference (P < .01). Controlling for age, gender, race, and insurance status, HbA1c in May 2020 (meanadj = 7.73) was significantly higher than in May 2019 (meanadj = 7.16). CONCLUSIONS: During the early months of the COVID-19 pandemic, glycemic control in our patient population was significantly worse than during the same period in 2019 (mean HbA1c difference = 0.57). Contrary to our expectations, we did not find associations between patient demographic variables and glycemic control, including race.


Assuntos
Hemoglobinas Glicadas/metabolismo , Controle Glicêmico/estatística & dados numéricos , Idoso , COVID-19 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Retrospectivos , SARS-CoV-2 , Determinantes Sociais da Saúde
3.
Mar Pollut Bull ; 129(1): 1-7, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29680525

RESUMO

Like fishing, natural regime shifts and human-induced environmental changes are often equally important factors in driving fish stock declines. In the Northwestern Arabian Gulf, many fish stocks are declining, raising questions about the reduction in the flow of Tigris-Euphrates rivers. Here we investigate the relationship between Tigris-Euphrates river flow and the estimated recruitment patterns from assessment models. We found a positive correlation between the estimated finfish recruitment trends and the flow of Tigris-Euphrates rivers. Additionally, the assessment model showed remarkably weak compensation ratio, likely indicating a reduction in the productivity of nursery area of two finfish stocks but not in that of the crustacean stock. Our investigation would be very critical in providing guidelines to the government agencies in the Northwestern Arabian Gulf as well as countries of Tigris-Euphrates basins: to consider the impacts associated with reductions in Tigris-Euphrates river flows on the ecosystem services of the region.


Assuntos
Monitoramento Ambiental/métodos , Peixes/fisiologia , Rios/química , Movimentos da Água , Animais , Ecossistema , Oceano Índico , Modelos Teóricos , Dinâmica Populacional
4.
Front Microbiol ; 8: 1922, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29067005

RESUMO

Self-transmissible and mobilizable plasmids contribute to the emergence and spread of multidrug-resistant bacteria by enabling the horizontal transfer of acquired antibiotic resistance. The objective of this study was to capture and characterize self-transmissible and mobilizable resistance plasmids from a coastal wetland impacted by urban stormwater runoff and human wastewater during the rainy season. Four plasmids were captured, two self-transmissible and two mobilizable, using both mating and enrichment approaches. Plasmid genomes, sequenced with either Illumina or PacBio platforms, revealed representatives of incompatibility groups IncP-6, IncR, IncN3, and IncF. The plasmids ranged in size from 36 to 144 kb and encoded known resistance genes for most of the major classes of antibiotics used to treat Gram-negative infections (tetracyclines, sulfonamides, ß-lactams, fluoroquinolones, aminoglycosides, and amphenicols). The mobilizable IncP-6 plasmid pLNU-11 was discovered in a strain of Citrobacter freundii enriched from the wetland sediments with tetracycline and nalidixic acid, and encodes a novel AmpC-like ß-lactamase (blaWDC-1), which shares less than 62% amino acid sequence identity with the PDC class of ß-lactamases found in Pseudomonas aeruginosa. Although the IncR plasmid pTRE-1611 was captured by mating wetland bacteria with P. putida KT2440 as recipient, it was found to be mobilizable rather than self-transmissible. Two self-transmissible multidrug-resistance plasmids were also captured: the small (48 kb) IncN3 plasmid pTRE-131 was captured by mating wetland bacteria with Escherichia coli HY842 where it is seemed to be maintained at nearly 240 copies per cell, while the large (144 kb) IncF plasmid pTRE-2011, which was isolated from a cefotaxime-resistant environmental strain of E. coli ST744, exists at just a single copy per cell. Furthermore, pTRE-2011 bears the globally epidemic blaCTX-M-55 extended-spectrum ß-lactamase downstream of ISEcp1. Our results indicate that urban coastal wetlands are reservoirs of diverse self-transmissible and mobilizable plasmids of relevance to human health.

5.
Phys Rev Lett ; 117(24): 245001, 2016 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-28009190

RESUMO

The first cryogenic deuterium and deuterium-tritium liquid layer implosions at the National Ignition Facility (NIF) demonstrate D_{2} and DT layer inertial confinement fusion (ICF) implosions that can access a low-to-moderate hot-spot convergence ratio (1230) DT ice layer implosions. Although high CR is desirable in an idealized 1D sense, it amplifies the deleterious effects of asymmetries. To date, these asymmetries prevented the achievement of ignition at the NIF and are the major cause of simulation-experiment disagreement. In the initial liquid layer experiments, high neutron yields were achieved with CRs of 12-17, and the hot-spot formation is well understood, demonstrated by a good agreement between the experimental data and the radiation hydrodynamic simulations. These initial experiments open a new NIF experimental capability that provides an opportunity to explore the relationship between hot-spot convergence ratio and the robustness of hot-spot formation during ICF implosions.

6.
Phys Rev Lett ; 117(3): 035001, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27472117

RESUMO

First measurements of hydrodynamic growth near peak implosion velocity in an inertial confinement fusion (ICF) implosion at the National Ignition Facility were obtained using a self-radiographing technique and a preimposed Legendre mode 40, λ=140 µm, sinusoidal perturbation. These are the first measurements of the total growth at the most unstable mode from acceleration Rayleigh-Taylor achieved in any ICF experiment to date, showing growth of the areal density perturbation of ∼7000×. Measurements were made at convergences of ∼5 to ∼10× at both the waist and pole of the capsule, demonstrating simultaneous measurements of the growth factors from both lines of sight. The areal density growth factors are an order of magnitude larger than prior experimental measurements and differed by ∼2× between the waist and the pole, showing asymmetry in the measured growth factors. These new measurements significantly advance our ability to diagnose perturbations detrimental to ICF implosions, uniquely intersecting the change from an accelerating to decelerating shell, with multiple simultaneous angular views.

7.
West Indian Med J ; 65(1): 27-31, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26716802

RESUMO

OBJECTIVE: To determine current red cell transfusion practices, transfusion indications and their relationship to patient outcome in intensive care unit (ICU) patients at the University Hospital of the West Indies (UHWI). METHOD: An observational study was conducted over seven months in the two ICUs at the UHWI, on all patients over 16 years who had been admitted for more than 24 hours. Patient demographics, indication(s) for transfusion, haemoglobin level at the time of transfusion, details of ICU admission and patient outcome were recorded. Data analysis was done using Stata v12. RESULTS: Of the 203 patients included in the study, 79 were transfused (39%). A low haemoglobin level was the most common indication for transfusion, with a mean of 7.3 ± 1.5 g/dL. Patients who were transfused had higher phlebotomy volumes [61.9 versus 126.1 mL, p < 0.001], were more likely to require mechanical ventilation (p = 0.002) and inotropic support (p = 0.007). Most were surgical patients (p = 0.01) and were post-open heart/thoracic surgery (66% transfusion rate). Patient outcome was correlated with transfusion, as transfused patients had longer ICU stays (13.0 versus 6.7 days, p < 0.001) and increased mortality rates (32.9% compared to 20.2%, p = 0.04). Most transfusions occurred within the first week of admission (83.5%). CONCLUSION: The mean haemoglobin for transfusion at the ICU, UHWI, is 7.3 g/dL, just above the recommended trigger of 7.0 g/dL in a restrictive transfusion practice. Transfusion policies are needed to better allocate a scarce commodity and minimize complications associated with blood transfusion.

8.
J Phys Condens Matter ; 27(32): 325702, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26214712

RESUMO

X-ray diffraction, specific heat, magnetic susceptibility and inelastic x-ray scattering measurements on the transurarium oxypnictides NpFeAsO and NpFeAsO0.85F0.15 are presented. No superconductivity down to 2 K was observed upon fluorine doping, contrary to the structurally analogous rare-earth pnictides. No modification of the phonon density of states was observed upon doping with fluorine. We discuss our results in light of the latest experimental and theoretical studies on the role of phonons in the superconducting pnictide compounds.

9.
West Indian Med J ; 63(3): 226-33, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25314279

RESUMO

OBJECTIVE: To compare the guidelines in the University Hospital of the West Indies (UHWI) acute asthma management protocol with actual practice in the Accident and Emergency Department. METHODS: A prospective docket audit was done of all consecutive medical records of patients, presenting with a diagnosed acute asthmatic attack between June 1 and September 30, 2010, to the emergency department of the UHWI. A convenient sample was used. The audit tool used was created from the UHWI protocol for the emergency management of asthma in adults and children, as well as the British Adult Asthma Audit Tool. The audit tool assessed three main sections: initial assessment, initial management, and discharge considerations. Data were coded and entered in Microsoft Excel 2007 and statistical analyses conducted using Stata version 10. Management patterns were compared to the actual protocol and then discussed. RESULTS: A total of 15 864 patients were seen during the study period. Of these, a total of 293 patients were seen for a presentation of acute asthma. More females (57.3%) than males were seen, with the mean age of 33.53 years. Only 31% of patients were given a severity assessment of mild, moderate, or severe. Peak expiratory flow rate (PEFR) was attempted and recorded in 62%, but only 18.1% of patients had both pre and post PEFR done. Only 4.4% of patients were administered nebulizations within the suggested time frame. Positively, 94.2% of patients were given a prescription for inhaled corticosteroids and bronchodilators to continue post-discharge. CONCLUSIONS: Acute asthma management still remains an area of medical practice that continues to have long-standing difficulties. Failure to assess and document the severity of asthma attacks along with the under-utilization of PEFR was noted.

10.
West Indian Med J ; 63(3): 217-25, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25314278

RESUMO

OBJECTIVES: The study assessed compliance among health workers in the Emergency Room at the University Hospital of the West Indies with universal precautions. This was done by determining the knowledge, practices and perceptions of staff of universal precautions and by assessing compliance. Reported adherence with universal precautions was compared with observed practice. METHODS: This was a cross-sectional study conducted over a one-year period. It was approved by the University Hospital of the West Indies/University of the West Indies/Faculty of Medical Sciences Ethics Committee. Data were analysed using Stata version 11.1. RESULTS: During the study period, 67 persons gave consent for the study, data were obtained for 62 of these participants and 52 of the respondents were observed. All of the participants were aware that universal precautions related to blood. Eighty-six per cent erroneously thought that universal precautions apply to urine. Seventy-nine per cent of the participants reported always washing their hands after performing a procedure and 43.5% reported always washing their hands before a procedure. Just over half of the participants reported always wearing gloves while doing procedures (56.5%). Only 9% reported always using a gown with a trauma patient. However, 31% and 43.3% reported wearing a gown when placing a chest tube and when anticipating splashes, respectively. Of those participants who reported washing their hands often after a procedure, over 30% did not perform hand-washing when observed. Fifty per cent of persons that reported never recapping needles were observed to recap needles by hand. CONCLUSION: The study revealed that compliance among staff in the Emergency Room with universal precautions was unsatisfactory. The need for education in this area was recognized.

11.
Int J Clin Pract ; 68(8): 972-85, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24703195

RESUMO

AIMS: To evaluate the safety and tolerability of the ß3 -adrenoceptor agonist, mirabegron, in patients with overactive bladder (OAB). METHODS: Tolerability and safety data from three 12-week, randomised, placebo-controlled, double-blind, Phase III trials (Studies 046, 047 and 074) were pooled by treatment group. The three studies were of a similar design, although the assessed doses of mirabegron [25, 50 or 100 mg once daily (qd)] varied, and tolterodine extended release (ER) 4 mg was included as an active-control arm in Study 046 only. Tolerability and safety data from a 1-year, randomised, double-blind, Phase III trial (Study 049) are also presented. Safety variables included the incidence and severity of treatment-emergent adverse events (TEAEs), vital signs and electrocardiogram data. RESULTS: Mirabegron (25, 50 or 100 mg qd) was safe and well-tolerated in patients with OAB over 12-week (n = 2736) and 1-year (n = 1632) periods. The incidence of TEAEs and treatment discontinuations as a result of TEAEs was low; the majority were mild in severity and few were serious. Hypertension, nasopharyngitis and urinary tract infection were the most common TEAEs with mirabegron. The mirabegron tolerability profile was similar to that seen with placebo and tolterodine ER 4 mg, except for dry mouth, which occurred, on average, five times less frequently with mirabegron than tolterodine ER 4 mg. In the pooled 12-week analysis, mirabegron 50 mg was associated with placebo-adjusted mean increases of 0.4-0.6 mmHg in blood pressure and approximately one beat per minute in pulse rate, both reversible upon treatment discontinuation. The incidence of Major Adverse Cardiovascular Events as adjudicated by an independent cardiovascular committee was low and similar across treatment groups. CONCLUSION: The favourable tolerability profile of mirabegron in patients with OAB may allow improved treatment compliance compared with antimuscarinics, with important implications for patient outcomes.


Assuntos
Acetanilidas/farmacologia , Antagonistas de Receptores Adrenérgicos beta 3/farmacologia , Tolerância a Medicamentos , Uso Off-Label , Tiazóis/farmacologia , Resultado do Tratamento , Bexiga Urinária Hiperativa/tratamento farmacológico , Agentes Urológicos/administração & dosagem , Acetanilidas/uso terapêutico , Adolescente , Antagonistas de Receptores Adrenérgicos beta 3/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Estudos Prospectivos , Tiazóis/uso terapêutico , Agentes Urológicos/efeitos adversos
12.
Lupus ; 23(10): 1092-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24644009

RESUMO

Vitamin D has important effects on the immune system as it has been shown to exert antiproliferative and relative immunosuppressant effects. Low levels of this hormone may contribute to the immune activation in systemic lupus erythematosus (SLE) and other autoimmune diseases. Serum levels of 25-OH vitamin D were measured in 75 patients with SLE in Jamaica, using an enzyme-linked immunoassay. Correlations with clinical data and disease activity as determined by the BILAG index were determined. Of a total of 75 patients, 33 (44%) had vitamin D sufficiency with mean vitamin D level of 39.45 ng/ml (range, 30.35-58.16). Forty-two (56%) patients had either vitamin D deficiency or insufficiency, 30 (40%) had vitamin D insufficiency, mean 26.36 ng/ml (range, 20.26-29.88), and 12 (16%) had vitamin D deficiency, mean 16.07 ng/ml (range, 7.78-19.90). There was an overall negative relationship between the total disease activity score using the BILAG index and vitamin D levels, and this was influenced primarily by the relationship seen among the vitamin D-deficient subgroup. This was also impacted on by a patient population that was significantly skewed toward low disease activity. The negative association trended toward statistical significance. Vitamin D deficiency is prevalent among patients with SLE in Jamaica. A relationship between low serum levels of vitamin D and SLE activity may occur.


Assuntos
Lúpus Eritematoso Sistêmico/sangue , Deficiência de Vitamina D/sangue , Vitamina D/análogos & derivados , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Criança , Feminino , Hospitais Universitários , Humanos , Jamaica/epidemiologia , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Índice de Gravidade de Doença , Vitamina D/sangue , Deficiência de Vitamina D/diagnóstico , Deficiência de Vitamina D/epidemiologia , Adulto Jovem
13.
West Indian Med J ; 63(7): 711-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25867578

RESUMO

OBJECTIVE: To determine the clinical factors associated with the length of hospitalization and mortality in patients with sickle cell disease (SCD). METHODS: All patients with SCD admitted to the medical wards of the University Hospital of the West Indies, Jamaica, over a five-year period, January 1 to December 31, 2010, were reviewed. Data were extracted from hospital charts and comprised demographic and clinical information, investigations, interventions, duration of stay, pathological data and outcomes. RESULTS: There were 105 patients reviewed; 84% were genotype Hb SS. Females accounted for 59% and males 41%. Overall mean age was 32.5 years (SD 13.7, range 12-66 years). The mean length of hospitalization was 10.2 days (SD 10.9, range 1-84 days). The main admission diagnoses were painful crisis, acute chest syndrome, severe anaemia, sepsis, hepatic sequestration, congestive cardiac failure and renal failure. The mean value for the following laboratory investigations were: haemoglobin 7.7 g/dL (SD 2.8), total white blood cell count 21.7 x 109/L (SD 14.2), platelet count 320 x 109/L (SD 191.9), blood urea 9.8 mmol/L (SD 11.9) and serum creatinine 198 umol/L (SD 267.9). Medical interventions included: blood transfusions in 20.9%, 55% received antibiotics and 74% received narcotic analgesia. There were 40 deaths with four autopsies done. The mortality rate for SCD was 38%. There were 189 repeat SCD admissions. CONCLUSION: Sickle cell disease still carries a high morbidity and mortality in patients admitted to hospital. Recurrent admissions are a concern, as they impact on patient's morbidity and quality of life.

14.
West Indian med. j ; 62(9): 831-834, Dec. 2013. graf, tab
Artigo em Inglês | LILACS | ID: biblio-1045764

RESUMO

OBJECTIVE: To determine the correlation of ultrasonographic estimation of fetal weight and actual birthweight and the impact of the level of resident s training on the results. METHODS: This was a prospective study of 90 women with term pregnancies. Ultrasound estimated fetal weight (EFW) was calculated by a pre-programmed Hadlock formula. Days from ultrasound to delivery were less than seven. The EFW was compared to the actual birthweight at delivery. The year of training of the resident that performed the ultrasound was recorded. Exclusion criteria included diabetes mellitus and known fetal anomalies. RESULTS: Mean age was 28 years, parity was 0 to 4 and mean gestational age was 38 weeks. There was an average over-estimation of 64.8 grams. The difference between mean EFW and mean birthweight was not significant (p = 0.067). The difference between mean EFW and mean birthweight when calculated according to year of residency was not significant, p = 0.075 and 0.402for junior and senior residents, respectively. CONCLUSION: There is good correlation between residents' ultrasonographic estimation of fetal weight and actual birthweight at the UHWI. There was no significant difference in correlation between senior and junior residents. Developments in computer technology might contribute to decrease in the learning curve.


OBJETIVO: Determinar la correlación de la estimación ultrasonográfica del peso fetal y el peso real al nacer, y el impacto del nivel de formación del residente en los resultados. MÉTODOS: Se trató de un estudio prospectivo de 90 mujeres con embarazos a término. El peso fetal estimado (PFE) por ultrasonido fue calculado mediante una fórmula de Hadlock preprogramada. Los días transcurridos desde el ultrasonido hasta el parto fueron menos de siete. Se comparó el PFE con el peso real en el parto. Se registró el año de formación del residente que realizó el ultrasonido. Los criterios de exclusión criterios incluyeron diabetes mellitus y anomalías fetales conocidas. RESULTADOS: La edad promedio fue 28 años; la paridad fue de 0 a 4; la edad gestacional fue de 38 semanas. Hubo una sobreestimación promedio de 64.8 gramos. La diferencia entre el PFE promedio y el peso promedio al nacer no fue significativa (p = 0.067). La diferencia entre el PFE promedio y el peso promedio al nacer calculada según el año de residencia no fue significativa, siendo p = 0.075 y 0.402 para médicos en la primera y última etapa de su residencia, respectivamente. CONCLUSIÓN: Existe una buena correlación entre la estimación ultrasonográfica del peso fetal, realizada por los residentes, y el peso real al nacer en el HUWI. No hubo ninguna diferencia significativa en la correlación entre los residentes en sus primeras y últimas etapas. Los desarrollos en la tecnología informática pueden contribuir a la disminución de la curva de aprendizaje.


Assuntos
Humanos , Feminino , Gravidez , Recém-Nascido , Adulto , Peso ao Nascer , Ultrassonografia Pré-Natal , Competência Clínica , Peso Fetal , Internato e Residência , Estudos Prospectivos
15.
Phys Rev Lett ; 111(6): 065003, 2013 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-23971581

RESUMO

The first measurements of multiple, high-pressure shock waves in cryogenic deuterium-tritium (DT) ice layered capsule implosions on the National Ignition Facility have been performed. The strength and relative timing of these shocks must be adjusted to very high precision in order to keep the DT fuel entropy low and compressibility high. All previous measurements of shock timing in inertial confinement fusion implosions [T. R. Boehly et al., Phys. Rev. Lett. 106, 195005 (2011), H. F. Robey et al., Phys. Rev. Lett. 108, 215004 (2012)] have been performed in surrogate targets, where the solid DT ice shell and central DT gas regions were replaced with a continuous liquid deuterium (D2) fill. This report presents the first experimental validation of the assumptions underlying this surrogate technique.

16.
J Phys Condens Matter ; 25(26): 265401, 2013 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-23751600

RESUMO

The structural behaviour under compression of different lanthanide (La, Gd, Ho, Yb) and actinide (Am) monochalcogenides is studied by means of in situ high-pressure x-ray diffraction. All the investigated compounds crystallize at ambient conditions within a cubic (B1) NaCl-type structure but show different behaviours at high pressures. LaTe and AmTe undergo B1 to B2 (CsCl-type structure) phase transitions, starting at 9 GPa and 12 GPa, respectively. The high-pressure phase of AmTe exhibits an electronic transition, identified by an anomaly in the compression curve which is accompanied by a sample colour change. The other three monochalcogenides studied here show clear evidence of decomposition and amorphization under pressure and are, to the best of our knowledge, the first in the LnTe series to show a pressure-induced amorphization. The bulk moduli of all B1-type structure compounds are calculated using the third-order Birch-Murnaghan equation of state.


Assuntos
Elementos da Série Actinoide/química , Calcogênios/química , Elementos da Série dos Lantanídeos/química , Telúrio/química , Cristalização , Modelos Moleculares , Transição de Fase , Pressão , Teoria Quântica , Propriedades de Superfície , Difração de Raios X
17.
Bioorg Med Chem Lett ; 23(7): 2260-4, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23453067

RESUMO

7-Deazapurines are known to possess broad antiviral activity, however the 2'-C-methylguanosine analogue displays poor cell permeation and limited phosphorylation, thus is not an efficient inhibitor of hepatitis C virus (HCV) replication. We previously reported the 6-O-methyl entity as a prodrug moiety to increase liphophilicity of guanine nucleosides and the ProTide approach applied to 2'-C-methyl-6-O-methylguanosine has lead to potent HCV inhibitors now in clinical trials. In this Letter, we report the synthesis and biological evaluation of 2'-C-methyl-6-O-methyl-7-deaza guanosine and ProTide derivatives. In contrast to prior studies, removal of the N-7 of the nucleobase entirely negates anti-HCV activity compared to the 2'-C-methyl-6-O-methylguanosine analogues. To understand better this significant loss of activity, enzymatic assays and molecular modeling were carried out and suggested 2'-C-methyl-6-O-methyl-7-deaza guanosine and related ProTides do not act as efficient prodrugs of the free nucleotide, in marked contrast to the case of the parent guanine analogue.


Assuntos
Alanina/química , Amidas/farmacologia , Antivirais/farmacologia , Ésteres/farmacologia , Guanina/análogos & derivados , Hepacivirus/efeitos dos fármacos , Ácidos Fosfóricos/farmacologia , Amidas/síntese química , Amidas/química , Antivirais/síntese química , Antivirais/química , Ésteres/síntese química , Ésteres/química , Guanina/síntese química , Guanina/química , Guanina/farmacologia , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Ácidos Fosfóricos/síntese química , Ácidos Fosfóricos/química
18.
West Indian Med J ; 62(9): 829-32, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25117389

RESUMO

OBJECTIVE: To determine the correlation of ultrasonographic estimation of fetal weight and actual birthweight and the impact of the level of resident's training on the results. METHODS: A prospective study of 90 women with term pregnancies. Ultrasound estimated fetal weight (EFW) was calculated by a preprogrammed Hadlock formula. Days from ultrasound to delivery were less than seven. The EFW was compared to the actual birthweight at delivery. The year of training of the resident that performed the ultrasound was recorded. Exclusion criteria included Diabetes mellitus and known fetal anomalies. RESULTS: Mean age was 28 years, parity zero to four, mean gestational age 38 weeks. There was an average over-estimation of 64.8 grams. The difference between mean EFW and mean BWT was not significant (p = 0.067). The difference between mean EFW and mean BWT when calculated according to year of residency was not significant, p = 0.075 and 0.402 for junior and senior residents, respectively. CONCLUSION: There is good correlation between resident's ultrasonographic estimation of fetal weight and actual birthweight at the UHWI. There was no significant difference in correlation between senior and junior residents. Development in computer technology might contribute to decrease in the learning curve.

19.
West Indian med. j ; 61(8): 795-801, Nov. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-694343

RESUMO

OBJECTIVE: To identify the prevalence of oestrogen receptor (ER) positivity, and determine the relationship of ER status with patient and tumour characteristics, in patients with breast cancer. SUBJECTS AND METHODS: A retrospective review was conducted regarding the prevalence and clinical significance of ER in patients with breast cancer at the University Hospital of the West Indies (UHWI). Oestrogen receptor status results of 243 patients treated at UHWI were collected for the period January 1, 2002 to December 31, 2009. One hundred and ninety-nine were available for review. RESULTS: Oestrogen receptor status was positive in 125 (63%) and negative in 74 (37%) patients. Mean age at diagnosis was 52.6 ± 13.0 years for the ER positive group and 58.5 ± 14.23 years for the ER negative group. Postmenopausal women accounted for 55.2% and 64.9% of the ER positive and negative groups, respectively. Mean BMI was 28.0 kg/m² and 29.6 kg/m² for the ER positive and negative groups, respectively. Menarche occurred mainly between ages 12 and 13 years for both groups. Mean age at 1st parity was 23.4 years for the ER positive and 21.4 years for the ER negative group with median parity of two for both groups. The most prevalent risk factors were oral contraceptive pill (OCP) use (24.3% for the ER positive group, 17.1% for the ER negative group), family history of breast cancer (12.0%; 13.4%) and previous smoking (8.4%; 6.9%). Tumour node metastasis (TNM) stage was Stage II in most cases (46%; 49%). Infiltrating ductal histology was most common (81.5%; 87.7%). Her 2/ neu status was negative for most patients (91.3%; 91.5%). Most patients were disease free (77.6%; 70.0%) after an average follow-up period of 3.5 years. More persons in the ER negative group had locoregional recurrence (8%) and metastases (22%). CONCLUSIONS: Oestrogen receptor positive cohort was more prevalent. The ER negative group was older (p = 0.003).


OBJETIVO: Identificar la prevalencia del receptor de la positividad de receptor de estrógeno (RE), y determinar la relación del estatus de RE con el paciente y las características del tumor, en las pacientes con cáncer de mama. SUJETOS Y MÉTODOS: Se realizó un estudio retrospectivo con respecto a la prevalencia e importancia clínica del RE en los pacientes con cáncer de mama en el Hospital Universitario de West Indies (UHWI). Se recogieron los resultados del estatus del receptor de estrógeno de 243 pacientes tratados en UHWI en el periodo del 1 de enero de 2002 al 31 de diciembre de 2009. Ciento noventa y nueve estuvieron disponibles para examen. RESULTADOS: El estatus del receptor de estrógeno fue positivo en 125 (63%) y negativo en 74 (37%) pacientes. La edad promedio al momento del diagnóstico fue 52.6 ± 13.0 años para el grupo de RE positivo y 58.5 ± 14.23 años para el RE grupo negativo. Las mujeres menopáusicas representaron el 55.2% y el 64.9% del RE de los grupos positivos y negativos respectivamente. El índice de masa corporal (IMC) promedio fue 28.0 kg/m2 y 29.6 kg/m2 para el RE de los grupos positivos y negativos respectivamente. La menarquia ocurrió principalmente entre las edades de 12 y 13 años para ambos grupos. La edad promedio en la primera paridad fue 23.4 años para el grupo de RE positivo y 21.4 años para el de RE negativo, siendo la paridad mediana igual a dos para ambos grupos. Los factores de riesgo de mayor preponderancia fueron el uso de anticonceptivos orales (ACO) (24. 3% para el grupo de RE positivo, 17.1% para el grupo RE negativo); historia familiar de cáncer de mama (12.0%; 13.4%); y hábito de fumar con anterioridad (8.4%; 6.9%). De acuerdo con la estadificación tumor-nódulo-metástasis (TNM), se trataba de la Etapa II en la mayor parte de los casos (46%; 49%). La histología ductal infiltrante fue la más común (81.5%; 87.7%). El estatus Her2/neu fue negativo para la mayoría de las pacientes (91.3%; 91.5%). La mayoría de las pacientes se hallaban libres de enfermedad (77.6%; 70.0%) después de un periodo promedio de seguimiento de 3.5 años. En el grupo de RE negativo había más personas con recurrencia locoregional (8%) y metástasis (22%). CONCLUSIONES: La cohorte positiva del receptor de estrógeno positiva fue más prevaleciente. El grupo negativo de RE fue de mayor edad (p = 0.003).


Assuntos
Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/metabolismo , Receptores de Estrogênio/metabolismo , Fatores Etários , Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/secundário , Anticoncepcionais Orais , Jamaica , Menarca , Gradação de Tumores , Estadiamento de Neoplasias , Paridade , Pós-Menopausa/metabolismo , /metabolismo , Estudos Retrospectivos , Fumar
20.
Phys Rev Lett ; 108(21): 215004, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-23003273

RESUMO

Ignition implosions on the National Ignition Facility [J. D. Lindl et al., Phys. Plasmas 11, 339 (2004)] are underway with the goal of compressing deuterium-tritium fuel to a sufficiently high areal density (ρR) to sustain a self-propagating burn wave required for fusion power gain greater than unity. These implosions are driven with a very carefully tailored sequence of four shock waves that must be timed to very high precision to keep the fuel entropy and adiabat low and ρR high. The first series of precision tuning experiments on the National Ignition Facility, which use optical diagnostics to directly measure the strength and timing of all four shocks inside a hohlraum-driven, cryogenic liquid-deuterium-filled capsule interior have now been performed. The results of these experiments are presented demonstrating a significant decrease in adiabat over previously untuned implosions. The impact of the improved shock timing is confirmed in related deuterium-tritium layered capsule implosions, which show the highest fuel compression (ρR~1.0 g/cm(2)) measured to date, exceeding the previous record [V. Goncharov et al., Phys. Rev. Lett. 104, 165001 (2010)] by more than a factor of 3. The experiments also clearly reveal an issue with the 4th shock velocity, which is observed to be 20% slower than predictions from numerical simulation.

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