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1.
Angew Chem Int Ed Engl ; 63(19): e202402413, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38478719

RESUMO

Existing modelling tools, developed to aid the design of efficient molecular wires and to better understand their charge-transport behaviour and mechanism, have limitations in accuracy and computational cost. Further research is required to develop faster and more precise methods that can yield information on how charge transport properties are impacted by changes in the chemical structure of a molecular wire. In this study, we report a clear semilogarithmic correlation between charge transport efficiency and nuclear magnetic resonance chemical shifts in multiple series of molecular wires, also accounting for the presence of chemical substituents. The NMR data was used to inform a simple tight-binding model that accurately captures the experimental single-molecule conductance values, especially useful in this case as more sophisticated density functional theory calculations fail due to inherent limitations. Our study demonstrates the potential of NMR spectroscopy as a valuable tool for characterising, rationalising, and gaining additional insights on the charge transport properties of single-molecule junctions.

2.
Phys Chem Chem Phys ; 25(10): 7176-7183, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36810584

RESUMO

The electrical properties of large area molecular devices consisting of gold nanoparticles (GNPs) sandwiched between a double layer of alkanedithiol linkers have been examined. These devices have been fabricated by a facile bottom-up assembly in which an alkanedithiol monolayer is first self-assembled on an underlying gold substrate followed by nanoparticle adsorption and then finally assembly of the top alkanedithiol layer. These devices are then sandwiched between the bottom gold substrates and a top eGaIn probe contact and current-voltage (I-V) curves recorded. Devices have been fabricated with 1,5-pentanedithiol, 1,6-hexanedithiol, 1,8-octanedithiol and 1,10-decanedithiol linkers. In all cases the electrical conductance of the double SAM junctions with GNPs is higher than the corresponding and much thinner single alkanedithiol SAM. Competing models for this enhanced conductance are discussed and it is suggested to have a topological origin arising from how the devices assemble or structure during the fabrication, which gives more efficient cross device electron transport pathways without the GNPs producing short circuits.

3.
Nicotine Tob Res ; 24(12): 1959-1967, 2022 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-35704338

RESUMO

INTRODUCTION: Regulators are considering reducing the nicotine content in cigarettes to a minimally addictive level. This could particularly benefit smokers from populations vulnerable to heavy smoking and difficulties quitting. We assessed predictors of adherence among adults from vulnerable populations assigned to use very low nicotine content cigarettes (VLNCs) in randomized clinical trials, to identify characteristics of those who require additional assistance if a nicotine reduction policy were implemented. AIMS AND METHODS: Data came from three populations of vulnerable adult smokers assigned to use VLNC cigarettes (0.4 mg/g nicotine) during 12-week randomized controlled trials (n = 286): Socioeconomically disadvantaged women of reproductive age, opioid-maintained adults, and adults with affective disorders. Logistic and linear regressions modeled predictors of adherence based on changes in cotinine at week-6 and week-12 assessments relative to baseline, and as a 90% reduction in cotinine relative to baseline (full adherence: yes/no). Predictors included satisfaction with study cigarettes, craving, nicotine dependence severity, withdrawal, population membership, baseline affective-disorder symptoms, and sociodemographic characteristics. RESULTS: Dependence severity was negatively associated with both adherence measures at week 6 (p < .01), whereas increased satisfaction with study cigarettes and age were positively associated with both measures at weeks 6 and 12 (p < .01). Opioid-maintained adults exhibited reduced adherence and were less likely to reach full adherence at week 12 compared to disadvantaged women (p = .02). CONCLUSIONS: Factors associated with VLNC adherence in vulnerable populations are similar to those in the general population of smokers. Furthermore, studies are indicated investigating nicotine supplements (e.g., e-cigarettes, NRT) to support highly dependent adults faced with using VLNCs. IMPLICATIONS: This study identified factors predicting difficulty maintaining adherence to a regimen of very low nicotine content cigarettes (VLNC) among adults from vulnerable populations. Findings suggested that factors predicting difficulty maintaining adherence (greater nicotine dependence and low satisfaction with study-provided VLNC) were common across vulnerable smokers and the general population of adults who smoke. Furthermore, research should investigate alternatives to support highly dependent adults, such as pairing VLNC with supplemental, noncombusted nicotine. Some vulnerable populations (e.g., opioid-maintained adults) may be especially in need of supplemental, noncombusted nicotine.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Abandono do Hábito de Fumar , Produtos do Tabaco , Tabagismo , Adulto , Humanos , Feminino , Nicotina , Cotinina , Abandono do Hábito de Fumar/psicologia , Populações Vulneráveis , Analgésicos Opioides , Fumar
4.
Environ Microbiol ; 23(3): 1452-1468, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33283920

RESUMO

We evaluated Streptomyces biogeography in soils along a 1200 km latitudinal transect across New Zealand (NZ). Streptomyces diversity was examined using high-throughput sequencing of rpoB amplicons generated with a Streptomyces specific primer set. We detected 1287 Streptomyces rpoB operational taxonomic units (OTUs) with 159 ± 92 (average ± SD) rpoB OTUs per site. Only 12% (n = 149) of these OTUs matched rpoB sequences from cultured specimens (99% nucleotide identity cutoff). Streptomyces phylogenetic diversity (Faith's PD) was correlated with soil pH, mean annual temperature and plant community richness (Spearman's r: 0.77, 0.64 and -0.79, respectively; P < 0.05), but not with latitude. In addition, soil pH and plant community richness both explained significant variation in Streptomyces beta diversity. Streptomyces communities exhibited both high dissimilarity and strong dominance of one or a few species at each site. Taken together, these results suggest that dispersal limitation due to competitive interactions limits the colonization success of spores that relocate to new sites. Cultivated Streptomyces isolates represent a major source of clinically useful antibiotics, but only a small fraction of extant diversity within the genus have been identified and most species of Streptomyces have yet to be described.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Streptomyces , Nova Zelândia , Microbiologia do Solo , Streptomyces/genética
5.
BJOG ; 126(1): 114-121, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30126064

RESUMO

OBJECTIVE: To assess the effect of admission cardiotocography (ACTG) versus intermittent auscultation (IA) of the fetal heart (FH) in low-risk pregnancy during assessment for possible labour on caesarean section rates. DESIGN: A parallel multicentre randomised trial. SETTING: Three maternity units in the Republic of Ireland. POPULATION: Healthy, low-risk pregnant women, at term and ≥ 18 years old, who provided written informed consent. METHODS: Women were randomised to receive IA of the FH or 20 minutes ACTG on admission for possible labour onset, using remote telephone randomisation. Both groups received IA during labour, with conversion to continuous CTG as clinically indicated. MAIN OUTCOME MEASURES: Caesarean section (primary outcome), obstetric interventions (e.g. continuous CTG during labour, fetal blood sampling, augmentation of labour) and neonatal morbidity (e.g. metabolic acidosis, admission to the neonatal intensive care unit, neonatal death). RESULTS: Based on 3034 women (1513 and 1521 randomised to IA and ACTG, respectively), there was no statistical difference between the groups in caesarean section [130 (8.6%) and 105 (6.9%) for IA and ACTG groups, respectively; relative risk (RR) 1.24; 95% CI 0.97-1.58], or in any other outcome except for use of continuous CTG during labour, which was lower in the IA group (RR 0.90, 95% CI 0.86-0.93). CONCLUSION: Our study demonstrates no differences in obstetric or neonatal outcomes between IA and ACTG for women with possible labour onset, other than an increased risk for continuous CTG in women receiving ACTG. TWEETABLE ABSTRACT: No differences in outcomes between intermittent auscultation and admission cardiotocography for women with possible labour onset.


Assuntos
Cardiotocografia , Auscultação Cardíaca , Frequência Cardíaca Fetal , Início do Trabalho de Parto/fisiologia , Adulto , Cesárea/estatística & dados numéricos , Feminino , Humanos , Gravidez , Resultado da Gravidez , Estudos Retrospectivos
6.
Prev Med ; 117: 69-75, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29627511

RESUMO

BACKGROUND: Smoking prevalence is declining at a slower rate in rural than urban settings in the United States (U.S.), and known predictors of smoking do not readily account for this trend difference. Given that socioeconomic and psychosocial determinants of health disparities accumulate in rural settings and that life-course disadvantages are often greater in women than men, we examined whether smoking trends are different for rural and urban men and women. METHOD: We used yearly cross-sectional data (n = 303,311) from the U.S. National Survey on Drug Use and Health (NSDUH) from 2007 through 2014 to compare cigarette smoking trends in men and women across rural and urban areas. Current smoking status was modelled using logistic regression controlling for confounding risk factors. RESULTS: Regression derived graphs predicting unadjusted prevalence estimates and 95% confidence bands revealed that whereas the smoking trends of rural men, urban men, and urban women significantly declined from 2007 to 2014, the trend for rural women was flat. Controlling for demographic, socioeconomic and psychosocial predictors of smoking did not explain rural women's significantly different trend from those of the other three groups. CONCLUSION: Rural women lag behind rural men, urban men and urban women in decreasing smoking, a health disparity finding that supports the need for tobacco control and regulatory policies and interventions that are more effective in reducing smoking among rural women.


Assuntos
População Rural/estatística & dados numéricos , Fumar/epidemiologia , Produtos do Tabaco/estatística & dados numéricos , Uso de Tabaco/tendências , População Urbana/estatística & dados numéricos , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Sexuais , Fumar/tendências , Fatores Socioeconômicos , Estados Unidos/epidemiologia , Adulto Jovem
7.
Sex Transm Infect ; 93(6): 404-409, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28130506

RESUMO

OBJECTIVE: To determine the prevalence of newly diagnosed hepatitis C virus (HCV) and associated risk behaviours among men who have sex with men (MSM) in Manchester. METHOD: A survey among MSM attending four genitourinary medicine clinics in Manchester was carried out over 9 months in 2013. Participants were asked about recent sexual behaviour, recreational drug use and HIV status. All men were offered an HCV test. RESULTS: Overall, 2030 MSM completed a questionnaire and accepted an HCV test. Of whom, 0.9% (18) were newly diagnosed with HCV, including 1.8% (13/735) of HIV-positive MSM, 0.7% (3/440) of MSM of unknown HIV status and 0.2% (2/855) of HIV-negative MSM. HCV positivity was significantly associated with HIV status (p<0.001). When compared with HIV-negative MSM, HIV-positive MSM had higher rates of sharing snorting drug equipment, injecting drugs/'slamming' and using recreational drugs (all p<0.05) but lower rates of five or more sexual partners and insertive unprotected anal intercourse (p<0.05). MSM newly diagnosed with HCV had significantly higher prevalence of unprotected sex, sex with someone HCV positive, fisting, group sex, ever injecting drugs/'slamming' and recreational drug use (p<0.002). CONCLUSIONS: In this survey, HIV-positive MSM had significantly different drug use behaviour which may explain the higher HCV burden. However, HCV was also associated with HIV-negative MSM engaging in high-risk sexual practices. All MSM attending sexual health clinics must have a risk assessment and HCV screening should be offered based on the risk. Further studies are warranted to explore the interplay between HCV and HIV risk associated with drug use versus sexual practices.


Assuntos
Coinfecção/epidemiologia , Infecções por HIV/epidemiologia , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Programas de Rastreamento , Parceiros Sexuais , Sexo sem Proteção/estatística & dados numéricos , Adulto , Infecções por HIV/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Hepatite C/prevenção & controle , Hepatite C/psicologia , Homossexualidade Masculina/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Assunção de Riscos , Parceiros Sexuais/psicologia , Abuso de Substâncias por Via Intravenosa/epidemiologia , Abuso de Substâncias por Via Intravenosa/psicologia , Reino Unido/epidemiologia , População Urbana , Adulto Jovem
8.
Prev Med ; 104: 79-85, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28315761

RESUMO

Rural areas of the United States have a higher smoking prevalence than urban areas. However, no recent studies have rigorously examined potential changes in this disparity over time or whether the disparity can be explained by demographic or psychosocial characteristics associated with smoking. The present study used yearly cross sectional data from the National Survey on Drug Use and Health from 2007 through 2014 to examine cigarette smoking trends in rural versus urban areas of the United States. The analytic sample included 303,311 respondents. Two regression models were built to examine (a) unadjusted rural and urban trends in prevalence of current smoking and (b) whether differences remained after adjusting for demographic and psychosocial characteristics. Results of the unadjusted model showed disparate and diverging cigarette use trends during the 8-year time period. The adjusted model also showed diverging trends, initially with no or small differences that became more pronounced across the 8-year period. We conclude that differences reported in earlier studies may be explained by differences in rural versus urban demographic and psychosocial risk factors, while more recent and growing disparities appear to be related to other factors. These emergent differences may be attributable to policy-level tobacco control and regulatory factors that disproportionately benefit urban areas such as enforcement of regulations around the sale and marketing of tobacco products and treatment availability. Strong federal policies and targeted or tailored interventions may be important to expanding tobacco control and regulatory benefits to vulnerable populations including rural Americans.


Assuntos
Disparidades nos Níveis de Saúde , População Rural/estatística & dados numéricos , Fumar/epidemiologia , Fumar/tendências , População Urbana/estatística & dados numéricos , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Marketing , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , População Rural/tendências , Fatores Socioeconômicos , Produtos do Tabaco , Estados Unidos/epidemiologia , População Urbana/tendências
9.
J Public Health (Oxf) ; 38(3): 585-590, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26045472

RESUMO

BACKGROUND: The burden of disease relating to undiagnosed HIV infection is significant in the UK. BHIVA (British HIV Association) recommends population screening in high prevalence areas, expanding outside traditional antenatal/GUM settings. METHODS: RUClear 2011-12 piloted expanding HIV testing outside traditional settings using home-sampling kits (dry-blood-spot testing) ordered online. Greater Manchester residents (≥age 16) could request testing via an established, online chlamydia testing service (www.ruclear.co.uk). Participant attitudes towards this new service were assessed. Qualitative methods (thematic analysis) were used to analyse free-text data submitted by participants via hard copy questionnaires issued in all testing kits. RESULTS: 79.9% (2447/3062) participants completed questionnaires, of which 30.9% (756/2447) provided free-text data. Participants overwhelmingly supported the service, valuing particularly accessibility and convenience, allowing individuals to order tests any time of day and self-sample comfortably at home; avoiding the invasive nature of venipuncture and avoiding the need for face-to-face interaction with health services. The pilot was also clinically and cost-effective. CONCLUSION: Testing via home-sampling kits ordered online (dry-blood-spot testing) was felt to be an acceptable and convenient method for accessing a HIV test. Many individuals undertook HIV testing where they would otherwise not have been tested at all. Expansion of similar services may increase the uptake of HIV testing.


Assuntos
Atitude Frente a Saúde , Infecções por HIV/diagnóstico , Autocuidado/psicologia , Adolescente , Adulto , Idoso , Teste em Amostras de Sangue Seco/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Reino Unido , Adulto Jovem
10.
Eur J Gynaecol Oncol ; 37(2): 199-203, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27172745

RESUMO

PURPOSE OF INVESTIGATION: A retrospective study to evaluate six cycles of cisplatin 40 mg/m2 on day 1 and ifosfamide 1,200 mg/m2 daily on days 1 to 4 with Mesna every four weeks as first line treatment for 29 patients with a diagnosis of uterine carcinosarcoma. MATERIALS AND METHODS: A total of 23 of 29 patients received high dose rate intracavitary vaginal cuff brachytherapy (VCBT) with two fractions of seven Gy each. Median age was 65 years (range 40-82); 13 (44.8%) had Stage I disease, three (10.3%) had Stage II, eight (27.6%) had Stage III, and five (17.2%) patients had Stage IV disease. RESULTS: Most common toxicities were anemia grade 1 (35%)/grade 2 (45%), and neutropenia grade 3 (17%)/grade 4 (6.9%). Eleven dose modifications, four treatment discontinuations, and one patient withdrawal occurred. At a median follow up of 45 months (range 9 to 144), Progression free survival (PFS) was 20% and overall survival (OS) was 40% for Stage IV, PFS 75% and OS 62.5% for Stage III, compared to a PFS 75% and OS 72.2% for Stages I-II. Median OS for the entire group was 12.43 years (95% CI 3.69 to inf); for Stage I-III 12.4 years (6.1 to inf), and for Stage IV 15.6 months (95% CI 9.4 to inf). CONCLUSIONS: Cisplatin and ifosfamide chemotherapy with VCBT was well tolerated and has promising activity in uterine carcinosarcoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Braquiterapia/métodos , Carcinossarcoma/terapia , Neoplasias Uterinas/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia/induzido quimicamente , Carcinossarcoma/patologia , Quimiorradioterapia , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Feminino , Humanos , Ifosfamida/administração & dosagem , Mesna/uso terapêutico , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neutropenia/induzido quimicamente , Substâncias Protetoras/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias Uterinas/patologia
11.
Ann Surg Oncol ; 21(6): 1963-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24562930

RESUMO

PURPOSE: Basal subtype, as approximated by the triple-negative phenotype (ER-PR-Her2-), has correlated with higher LRR in recent studies. Indications for postmastectomy RT (PMRT) in women with 0-3 positive lymph nodes remain unclear. We evaluated the importance of biologic subtype in a cohort of women with LRR after mastectomy. METHODS: We identified 22 women with 0-3 positive lymph nodes at our institution who were initially treated with mastectomy (without post-mastectomy radiation), suffered LRRs, and had paraffin-embedded tissue blocks from the primary mastectomy specimen available for staining. None of these women received PMRT. We case-control matched these to 29 women with 0-3 positive nodes who had mastectomy (no PMRT) and remained without evidence of disease at last follow-up and had available primary specimens for processing. We matched controls for age (±3 years) and follow-up duration (<5 year vs. more). Paraffin-embedded specimens were used to construct a triple-redundant tissue microarray. We used conditional logistic regressions to study the association between each predictor and LRR. Results were summarized based on odds ratio (OR). RESULTS: On univariate analysis, ER+, PR+, or the combination was strongly associated with lower odds of LRR. Basal subtype, as approximated by ER-PR-Her2- (TN), was associated with higher LRR (OR 8.5, p = 0.048). Use of chemotherapy also was associated with lower LRR (OR 0.126, p = 0.0073). CONCLUSIONS: Our data are concordant with reports from others demonstrating that TN phenotype is associated with higher LRR and can be considered along with other predictors of LRR when selecting women for PMRT.


Assuntos
Biomarcadores Tumorais/análise , Recidiva Local de Neoplasia/química , Recidiva Local de Neoplasia/patologia , Neoplasias de Mama Triplo Negativas/química , Neoplasias de Mama Triplo Negativas/patologia , Antineoplásicos/uso terapêutico , Estudos de Casos e Controles , Feminino , Humanos , Metástase Linfática , Mastectomia , Fenótipo , Receptor ErbB-2/análise , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Estudos Retrospectivos , Neoplasias de Mama Triplo Negativas/terapia
12.
Diabet Med ; 31(3): 366-74, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24330155

RESUMO

AIMS: Pre-pregnancy care programmes can help to reduce morbidity and mortality associated with pregnancy in women with diabetes. However, uptake of a free pre-pregnancy care programme along the Irish Atlantic seaboard was only 30%. This study sought to better understand why women with diabetes mellitus (Type 1 and Type 2) choose to attend pre-pregnancy care services and to identify perceived barriers to attendance. METHODS: A participative health research method called the participative research process was used to facilitate 14 women with diabetes mellitus to create 'webs of ideas' on the reasons for attendance and non-attendance at a pre-pregnancy care programme, and potential solutions for each obstacle. RESULTS: The participants identified information on the risks of pregnancy as crucial for all childbearing women with diabetes, as lack of information was a major obstacle to attendance at pre-pregnancy care programmes. Practical constraints such as childcare difficulties and work commitments were also identified. Participants stressed that health practitioners need to focus on positive aspects of pregnancy and childbearing rather than focusing solely on the problematic aspects for women with diabetes mellitus. CONCLUSIONS: Women with diabetes need support and reassurance about their ability to control blood glucose and have a successful pregnancy while coping with the multiple challenges inherent in diabetes management and pregnancy. To increase uptake of pre-pregnancy care, a norm needs to be established that situates pre-pregnancy care as something every woman with diabetes will do, whether or not she is actively contemplating becoming a mother at the time. Active use of social media and facilitating peer support should be encouraged in pre-pregnancy services to facilitate attendance. The time has come to incorporate the skills of a clinical psychologist in the delivery of a pre-pregnancy service.


Assuntos
Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Internet , Gravidez em Diabéticas , Cuidado Pré-Natal , Apoio Social , Adolescente , Adulto , Glicemia/metabolismo , Anormalidades Congênitas/prevenção & controle , Complicações do Diabetes/prevenção & controle , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Necessidades e Demandas de Serviços de Saúde/organização & administração , Humanos , Hipertensão/prevenção & controle , Recém-Nascido , Irlanda/epidemiologia , Gravidez , Resultado da Gravidez , Gravidez em Diabéticas/epidemiologia , Cuidado Pré-Natal/psicologia , Cuidado Pré-Natal/estatística & dados numéricos
13.
Ultrasound Obstet Gynecol ; 44(6): 669-73, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24706487

RESUMO

OBJECTIVE: To determine the critical maternal antibody threshold for specialist referral in cases of RhD alloimmunization. METHODS: This was a retrospective cohort study, covering a 16-year period at the national tertiary fetal medicine center for management of alloimmunization. Data concerning RhD alloimmunized pregnant women were extracted from an institutional database and maternal anti-D antibody levels were cross-checked with the national reference laboratory. Fetal hemoglobin (Hb) levels were determined only at the first intrauterine transfusion (IUT) and were compared with the pretransfusion maternal anti-D antibody level (IU/mL). Sensitivity, specificity and positive and negative predictive values of maternal antibody thresholds for detecting moderate to severe (Hb ≤ 0.64MoM) fetal anemia were calculated. RESULTS: Between 1996 and 2011, 66 women underwent a first IUT for RhD alloimmunization at our institution. The highest serum anti-D antibody level was extracted for 208 RhD alloimmunized women who did not require IUT during the last 10 years of the study period. The traditional maternal antibody threshold of > 15 IU/mL failed to detect 20% of cases of moderate to severe fetal anemia. The ≥ 4 IU/mL threshold had 100% sensitivity but a 45% false-positive rate. The optimal anti-D antibody threshold for specialist referral in our population was ≥ 6 IU/mL; at this level, no case of moderate to severe anemia was missed and specificity was 61%. Use of this threshold would have eliminated 10% of referrals to our fetal medicine unit without compromising fetal outcomes. CONCLUSIONS: Setting the critical maternal RhD antibody level at >15 IU/mL does not provide sufficient sensitivity. The lower threshold of ≥ 4 IU/mL, though sensitive, is associated with a 45% false-positive rate. In our population, a threshold of ≥ 6 IU/mL minimizes false-positive referrals while maintaining 100% sensitivity for moderate to severe fetal anemia.


Assuntos
Anemia/imunologia , Doenças Fetais/diagnóstico , Isoanticorpos/sangue , Isoimunização Rh/imunologia , Adulto , Biomarcadores/sangue , Estudos de Coortes , Feminino , Doenças Fetais/imunologia , Humanos , Valor Preditivo dos Testes , Gravidez , Estudos Retrospectivos , Imunoglobulina rho(D) , Sensibilidade e Especificidade
14.
Ultrasound Obstet Gynecol ; 44(4): 461-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24407772

RESUMO

OBJECTIVE: To construct monochorionic diamniotic (MCDA) and dichorionic diamniotic (DCDA) twin reference ranges for umbilical artery (UA) pulsatility index (PI), UA resistance index (RI), fetal middle cerebral artery (MCA) PI and peak systolic velocity (PSV) and cerebroplacental ratio (CPR) from 24 weeks' to 38 weeks' gestation and compare these with published normal values for singleton pregnancies. METHODS: This prospective multicenter cohort study included 1028 unselected twin pairs recruited over a 2-year period. Participants with dichorionic twins underwent fortnightly ultrasound surveillance from 24 weeks' gestation, with monochorionic twins being followed every 2 weeks from 16 weeks until delivery. A total of 7536 fetal Doppler examinations in 618 twin pregnancies were included in the analysis, with reference ranges for MCDA and DCDA pregnancies constructed for each of the Doppler indices using multilevel modeling. RESULTS: UA-PI and UA-RI appear to be higher in twins than in singletons, and MCA-PI and MCA-PSV appear to be lower. The CPR also appears to be lower in twins than in singletons. Similar MCA indices were observed in MCDA and DCDA twins. CONCLUSION: We have established longitudinal reference ranges for UA-PI and UA-RI, MCA-PI and MCA-PSV and CPR in twin pregnancies, which appear to differ from those in singleton pregnancies. The derived twin-specific reference ranges may be more appropriate in the surveillance of these high-risk pregnancies. Applying the singleton CPR cut-off of ≤ 1.0 may lead to a large number of false-positive diagnoses of cerebral redistribution in twin fetuses.


Assuntos
Artéria Cerebral Média/diagnóstico por imagem , Gêmeos Dizigóticos , Gêmeos Monozigóticos , Artérias Umbilicais/diagnóstico por imagem , Adulto , Velocidade do Fluxo Sanguíneo , Estudos de Coortes , Feminino , Retardo do Crescimento Fetal/diagnóstico por imagem , Feto/irrigação sanguínea , Idade Gestacional , Humanos , Estudos Longitudinais , Gravidez , Gravidez de Alto Risco , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Valores de Referência , Ultrassonografia Pré-Natal
15.
Resusc Plus ; 19: 100709, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39104446

RESUMO

Introduction: This study aimed to explore the views and perceptions of Advanced Life Support (ALS) practitioners in two South African provinces on initiating, withholding, and terminating resuscitation in OHCA. Methodology: Semi-structured one-on-one interviews were conducted with operational ALS practitioners working within the prehospital setting in the Western Cape and Free State provinces. Recorded interviews were transcribed and subjected to inductive-dominant, manifest content analysis. After familiarisation with the data, meaning units were condensed, codes were applied and collated into categories that were then assessed, reviewed, and refined repeatedly. Results: A total of 18 ALS providers were interviewed. Five main categories were developed from the data analysis: 1) assessment of prognosis, 2) internal factors affecting decision-making, 3) external factors affecting decision-making, 4) system challenges, and 5) ideas for improvement. Factors influencing the assessment of prognosis were history, clinical presentation, and response to resuscitation. Internal factors affecting decision-making were driven by emotion and contemplation. External factors affecting decision-making included family, safety, and disposition. System challenges relating to bystander response and resources were identified. Ideas for improvement in training and support were brought forward. Conclusion: Many factors influence OHCA decision-making in the Western Cape and Free State provinces, and numerous system challenges have been identified. The findings of this study can be used as a frame of reference for prehospital emergency care personnel and contribute to the development of context-specific guidelines.

16.
Genes Immun ; 13(1): 98-102, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21833022

RESUMO

Previously, we have shown that pyruvate kinase, liver and red cell isoform (PKLR) deficiency protects mice in vivo against blood-stage malaria, and observed that reduced PKLR function protects human erythrocytes against Plasmodium falciparum replication ex vivo. Here, we have sequenced the human PKLR gene in 387 individuals from malaria-endemic and other regions in order to assess genetic variability in different geographical regions and ethnic groups. Rich genetic diversity was detected in PKLR, including 59 single-nucleotide polymorphisms and several loss-of-function variants (frequency 1.5%). Haplotype distribution and allele frequency varied considerably with geography. Neutrality testing suggested positive selection of the genein the sub-Saharan African and Pakistan populations. It is possible that such positive selection involves the malarial parasite.


Assuntos
Eritrócitos/enzimologia , Polimorfismo de Nucleotídeo Único , Piruvato Quinase/genética , Sequência de Aminoácidos , Ordem dos Genes , Haplótipos , Humanos , Desequilíbrio de Ligação , Malária/enzimologia , Malária/genética , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Piruvato Quinase/química , Alinhamento de Sequência
17.
Ir Med J ; 105(10): 335-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23495545

RESUMO

The provision of specialist palliative care to Irish patients suffering from motor neurone disease has not been described in the literature. The purpose of this study was to characterize the care provided at a Dublin hospice. Consecutive referrals between 1st January 1999 and 31st December 2008 (n=72) were reviewed. At the time of data collection, 61 (84.7%) were deceased, 9 (12.5%) were alive and the status of 2 (2.7%) was unknown. At first assessment, 48 (66%) had bulbar symptoms and 35 (49%) had respiratory symptoms, 50 (70%) were receiving Riluzole, 25 (35%) had a feeding tube and 13 (18%) were using non-invasive positive pressure ventilation (NIPPV). Median survival from the point of referral was 7 months (95% CI 4.5-9.4). Of the 61 deceased patients, 22 (36%) died at home, 22 (36%) died in the inpatient unit, 9 (15%) died in hospital and 8 (13%) died in a nursing home.


Assuntos
Doença dos Neurônios Motores/terapia , Cuidados Paliativos , Padrões de Prática Médica , Idoso , Esclerose Lateral Amiotrófica/terapia , Nutrição Enteral , Antagonistas de Aminoácidos Excitatórios/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença dos Neurônios Motores/diagnóstico , Respiração com Pressão Positiva , Estudos Retrospectivos , Riluzol/uso terapêutico
18.
Poult Sci ; 90(4): 901-13, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21406379

RESUMO

Probiotics are currently used to improve health and reduce enteric pathogens in poultry. However, the mechanisms by which they reduce or prevent disease are not known. Salmonella are intracellular pathogens that cause acute gastroenteritis in humans, and infections by nontyphoid species of Salmonella also can result in diarrhea, dehydration, and depression in poultry. Frequently, however, no clinical signs of infection are apparent in poultry flocks. In this study, day-of-hatch chicks were challenged with Salmonella enterica serovar Enteritidis (SE) and treated 1 h later with a poultry-derived, Lactobacillus-based probiotic culture (FloraMax-B11, Pacific Vet Group USA Inc., Fayetteville, AR). Cecae were collected 12 and 24 h posttreatment for Salmonella detection and RNA isolation for microarray analysis of gene expression. At both 12 and 24 h, SE was significantly reduced in chicks treated with the probiotic as compared with the birds challenged with only SE (P < 0.05). Microarray analysis revealed gene expression differences among all treatment groups. At 12 h, 170 genes were expressed at significantly different levels (P < 0.05), with a minimum difference in expression of 1.2-fold. At 24 h, the number of differentially regulated genes with a minimum 1.2-fold change was 201. Pathway analysis revealed that at both time points, genes associated with the nuclear factor kappa B complex, as well as genes involved in apoptosis, were significantly regulated. Based on this analysis, probiotic-induced differential regulation of the genes growth arrest-specific 2 (GAS2) and cysteine-rich, angiogenic inducer, 61 (CYR61) may result in increased apoptosis in the cecae of chicks. Because Salmonella is an intracellular pathogen, we suggest that increased apoptosis may be a mechanism by which the probiotic culture reduces Salmonella infection.


Assuntos
Ceco/fisiologia , Galinhas , Doenças das Aves Domésticas/genética , Probióticos/farmacologia , Salmonelose Animal/genética , Salmonella enteritidis/fisiologia , Animais , Ceco/microbiologia , Perfilação da Expressão Gênica/veterinária , Regulação Bacteriana da Expressão Gênica , Humanos , Lactobacillus , Análise de Sequência com Séries de Oligonucleotídeos/veterinária , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/prevenção & controle , RNA Bacteriano/química , RNA Bacteriano/genética , Distribuição Aleatória , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Salmonelose Animal/microbiologia , Salmonelose Animal/prevenção & controle
19.
Ir Med J ; 104(8): 243-5, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22125879

RESUMO

The aim of this audit was to assess the accuracy of transabdominal ultrasound scan in predicting chorionicity in twin pregnancies in our unit. The presence or absence of lambda sign, T-sign, dividing membrane thickness and number of placentae were used to determine chorionicity. We retrospectively analysed these antenatal markers in 268 sets of twins delivered over a 5 year period and compared it with the postpartum placental histology and neonatal gender. Of 268 twin deliveries, 204 (76%) had both chorionicity and placental histology to compare. 67 of 84 (80%) were correctly diagnosed antenatally as monochorionic and 137 of 151 (91%) as dichorionic. In 31 cases (15%) the ultrasound diagnosis of chorionicity didn't match placental histology. Seventeen were thought to be monochorionic antenatally but were confirmed dichorionic on placental histology. Overall chorionicity was correctly diagnosed in 171/204 (84%) using transabdominal ultrasound scan (USS) in all trimesters. However the sensitivity and specificity of USS was much higher for dichorionic twins when carried out before 14 weeks of gestation.


Assuntos
Córion/diagnóstico por imagem , Gêmeos , Ultrassonografia Pré-Natal/métodos , Adulto , Feminino , Idade Gestacional , Humanos , Gravidez , Estudos Retrospectivos , Sensibilidade e Especificidade
20.
Ir Med J ; 104(1): 17-20, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21387880

RESUMO

The aim of this study is to examine the trend in maternal postnatal readmission within six weeks of discharge from childbirth hospitalisation. It is a retrospective review of the maternity computer records system, patient's clinical notes and HIPE data base. All women who delivered babies weighing > 500 g and/ > or = 24 weeks gestational age at Our Lady of Lourdes Hospital, Drogheda, Ireland from 1st January 2005 to 31st December 2008 who were re-hospitalised within six weeks of discharge from hospital following child birth were included in the study. A total of 15782 women were delivered over the four year study period. Of these, 236 were readmitted. A series of chi-square analysis were conducted to assess the difference in readmission rates between the year 2008 86 (2.03%) and the years 2005-51(1.46%), 2006-39 (1.01%) and 2007-60 (1.42%). The readmission rate was found to be significantly higher in 2008 compared with the three preceding years. Complications of Caesarean section and secondary postpartum haemorrhage following spontaneous vaginal delivery constitute the major indications for readmission.


Assuntos
Parto Obstétrico/estatística & dados numéricos , Readmissão do Paciente/estatística & dados numéricos , Cesárea/efeitos adversos , Cesárea/estatística & dados numéricos , Distribuição de Qui-Quadrado , Feminino , Humanos , Irlanda/epidemiologia , Readmissão do Paciente/tendências , Complicações Pós-Operatórias/epidemiologia , Hemorragia Pós-Parto/epidemiologia , Estudos Retrospectivos
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