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1.
Ann Oncol ; 33(7): 693-701, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35398288

RESUMEN

BACKGROUND: Pancreatic cancer presents as advanced disease in >80% of patients; yet, appropriate ages to consider prevention and early detection strategies are poorly defined. We investigated age-specific associations and attributable risks of pancreatic cancer for established modifiable and non-modifiable risk factors. PATIENTS AND METHODS: We included 167 483 participants from two prospective US cohort studies with 1190 incident cases of pancreatic cancer during >30 years of follow-up; 5107 pancreatic cancer cases and 8845 control participants of European ancestry from a completed multicenter genome-wide association study (GWAS); and 248 893 pancreatic cancer cases documented in the US Surveillance, Epidemiology, and End Results (SEER) Program. Across different age categories, we investigated cigarette smoking, obesity, diabetes, height, and non-O blood group in the prospective cohorts; weighted polygenic risk score of 22 previously identified single nucleotide polymorphisms in the GWAS; and male sex and black race in the SEER Program. RESULTS: In the prospective cohorts, all five risk factors were more strongly associated with pancreatic cancer risk among younger participants, with associations attenuated among those aged >70 years. The hazard ratios comparing participants with three to five risk factors with those with no risk factors were 9.24 [95% confidence interval (CI) 4.11-20.77] among those aged ≤60 years, 3.00 (95% CI 1.85-4.86) among those aged 61-70 years, and 1.46 (95% CI 1.10-1.94) among those aged >70 years (Pheterogeneity = 3×10-5). These factors together were related to 65.6%, 49.7%, and 17.2% of incident pancreatic cancers in these age groups, respectively. In the GWAS and the SEER Program, the associations with the polygenic risk score, male sex, and black race were all stronger among younger individuals (Pheterogeneity ≤0.01). CONCLUSIONS: Established risk factors are more strongly associated with earlier-onset pancreatic cancer, emphasizing the importance of age at initiation for cancer prevention and control programs targeting this highly lethal malignancy.


Asunto(s)
Estudio de Asociación del Genoma Completo , Neoplasias Pancreáticas , Humanos , Masculino , Neoplasias Pancreáticas/etiología , Neoplasias Pancreáticas/genética , Estudios Prospectivos , Factores de Riesgo , Neoplasias Pancreáticas
2.
Soft Matter ; 18(38): 7415-7421, 2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-36129321

RESUMEN

Absorption measurements allow the orientational order parameter of four dyes in the lyotropic chromonic liquid crystal di-sodium cromoglycate (DSCG) to be determined. The dye order parameters are small, except for dyes that intercalate between the DSCG molecules of the rod-like assemblies. The dye order parameters decrease with increasing temperature faster than the nematic order parameter of the DSCG assemblies. For intercalating dyes, the measured dye order parameter varies with the wavelength of the measurement because both intercalated and non-intercalated dye molecules contribute. On the contrary, measurements of the dye order parameter using fluorescence are sensitive only to intercalated dye molecules and produce values that reflect the order parameter of the DSCG assemblies. Therefore, the temperature and concentration dependence of the DSCG order parameter is also explored, since data of this kind on this often-studied system are lacking. Finally, the association constant of one of the intercalating dyes with the DSCG assemblies is determined, yielding a value considerably less than what is found for the same dye with DNA.


Asunto(s)
Cristales Líquidos , Colorantes , Cromolin Sódico/química , ADN/química , Cristales Líquidos/química , Temperatura
3.
Biol Lett ; 18(11): 20220395, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36448369

RESUMEN

Ancient, species-poor lineages persistently occur across the Tree of life. These lineages are likely to contain unrecognized species diversity masked by the low rates of morphological evolution that characterize living fossils. Halecomorphi is a lineage of ray-finned fishes that diverged from its closest relatives before 200 Ma and is represented by only one living species in eastern North America, the bowfin, Amia calva Linnaeus. Here, we use double digest restriction-site-associated DNA sequencing and morphology to illuminate recent speciation in bowfins. Our results support the delimitation of a second living species of Amia, with the timing of diversification dating to the Plio-Pleistocene. This delimitation expands the species diversity of an ancient lineage that is integral to studies of vertebrate genomics and development, yet is facing growing conservation threats driven by the caviar fishery.


Asunto(s)
Fósiles , Vertebrados , Animales , Vertebrados/genética , Explotaciones Pesqueras , Aletas de Animales , Cabeza
4.
J Fish Biol ; 99(2): 364-372, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33864690

RESUMEN

Production and outmigration of young-of-year (YOY) northern pike from natal sites in Lower Green Bay, WI, USA, were documented over three consecutive years (2013-2015). We tested the hypothesis that spawning success and outmigration characteristics of YOY northern pike would vary among natural and anthropogenically modified habitats. Sixteen focal study locations were surveyed, including a restored natural wetland, agricultural drainage ditches, a flooded forested wetland and several unimpounded tributaries. We collected 1469 YOY northern pike with most individuals (N = 1163) originating from a flooded forested wetland on the east shore. Most sites produced YOY in all years (range N = 2-1145 individuals among study years). Outmigration ranged between 1 and 40 days during 2013-2015. Greater production and extended outmigration times occurred at most sites in 2014 (range 17-40 days) when the region experienced a late spring with heavy precipitation. In contrast, the lowest production and shortest outmigration period occurred at most sites in 2015 (range 14-23 days) when environmental conditions reflected regional averages. Outmigration began nearly 3 weeks earlier in 2015 (5/8) than in other study years (8 June 2013 and 25 May 2014). Total length (TL) of outmigrating northern pike ranged between 17 and 138 mm. Total length of YOY was significantly different among sites in 2013 and 2014, with the smallest fish (17 mm TL) outmigrating from agricultural ditches in both years. There were no significant variations in size among sites in 2015 (range 21-95 mm TL). Our results indicate significant variation in YOY northern pike outmigration characteristics within Lower Green Bay that may reflect the interplay between adult spawning site selection and annual weather patterns. Our findings highlight the importance of quantifying overlooked habitats in regions of mixed development.


Asunto(s)
Bahías , Esocidae , Animales , Peces , Estaciones del Año , Wisconsin
5.
Indian J Crit Care Med ; 25(9): 976-980, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34963713

RESUMEN

AIM AND OBJECTIVE: Fogging of eyeglasses while wearing N95 respirators is common. It is commonly held that the N95 respirator has a poor fit if there is fogging of eyeglasses. We conducted this prospective, pilot study to determine if fogging of eyeglasses predicts poor fit of N95 respirator. MATERIALS AND METHODS: Seventy volunteer healthcare workers from a tertiary intensive care unit in Sydney, Australia participated. The participants donned one of the following N95 respirators: three-panel flat-fold respirator (3M 1870), cup-shaped respirator (3M 1860), or a duckbill respirator. After a satisfactory "user seal check" as recommended by the manufacturer, the participants donned eyeglasses and checked for fogging. A quantitative fit test (QnFT) of the respirator was then performed (using PortaCount Respirator Fit Tester 8048, TSI Inc., Minnesota, USA). A fit factor of <100 on quantitative fit testing indicates poor fit. The sensitivity and specificity for fogging of eyeglasses (index test) to predict the poor fit of N95 respirator was determined, compared to QnFT (gold standard test). RESULTS: Fogging of eyeglasses as a predictor of poor respirator fit (i.e., fit factor <100 on QnFT) had sensitivity of 71% (95% CI, 54-85%) and specificity 46% (95% CI, 29-63%). The odds ratio of fogging as a predictor for poor fit was 2.10 (95% CI, 0.78-5.67), with a two-tailed p-value of 0.22 (not significant). The receiver operating characteristic curve for fogging of eyeglasses as a diagnostic test had the area under the curve of 0.59. CONCLUSION: Fogging of eyeglasses is neither a sensitive nor a specific predictor for poor fit of N95 respirators. HOW TO CITE THIS ARTICLE: Kyaw S, Johns M, Lim R, Stewart WC, Rojas N, Thambiraj SR, et al. Prediction of N95 Respirator Fit from Fogging of Eyeglasses: A Pilot Study. Indian J Crit Care Med 2021;25(9):976-980.

6.
Indian J Crit Care Med ; 25(9): 981-986, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34963714

RESUMEN

N95 respirators and safety goggles are important components of personal protective equipment to reduce the spread of airborne infections, such as COVID-19, among healthcare workers. Poor N95 respirator seal may reduce its protective effect, thereby increasing transmission. Quantitative fit testing is an established way of assessing the N95 respirator fit, which provides a quantitative measure for seal, called the fit factor. Duckbill N95 respirators frequently fail the fit test. We hypothesized that using safety goggles with a wraparound elastic headband will increase their fit-factor by reinforcing the seal between the face and the upper margin of the respirator. We studied the effect of safety goggles with a wraparound elastic headband (3M™ Chemical Splash Resistant Goggles, ID 70006982741) on the fit factor of two types of Duckbill N95 respirators (Halyard FLUIDSHIELD*3, Model 99SA070M, and ProShield® N95 Model TN01-11) in 63 healthy volunteers in a nonrandomized, before-and-after intervention study design. The mean fit factor increased from 69.4 to 169.1 increased from 17/63 (27%) to 46/63 (73%) after the intervention (p <0.0001, OR 3 [95% CI = 4.9-1223]). This is the first study to explore the impact of safety goggles on N95 respirator fit. We conclude that the use of safety goggles with a wraparound elastic headband increases the fit factor of the tested Duckbill N95 respirators. HOW TO CITE THIS ARTICLE: Johns M, Kyaw S, Lim R, Stewart WC, Thambiraj SR, Shehabi Y, et al. Fit Factor Change on Quantitative Fit Testing of Duckbill N95 Respirators with the Use of Safety Goggles. Indian J Crit Care Med 2021;25(9):981-986.

7.
J Exp Zool B Mol Dev Evol ; 328(7): 596-606, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28980772

RESUMEN

The spotted gar (Lepisosteus oculatus) shows a disjunct natural distribution, with a core population extending from the central Mississippi River Basin to the U.S. gulf coast and a peripheral population in the southern Great Lakes Basin. Despite significant conservation concerns for this species in the Great Lakes watersheds where it occurs, few genetic examinations and comparisons of these populations have been performed. We investigated inter- and intrapopulational variation in several mitochondrial genetic markers (cytochrome oxidase subunit I, COI; cytochrome oxidase subunit II, COII; and 16S rRNA, 16S) from spotted gars taken from core and peripheral populations. Genetic diversity was highest in the Mississippi River Basin and lowest in the Great Lakes Basin, while the Nueces River Basin (Texas) population showed the greatest level of divergence from other populations. Average genetic distance among core and peripheral populations was over an order of magnitude less than that seen between L. oculatus and its sister species, the Florida gar (L. platyrhincus), although a significant correlation was found between genetic and geographical distance in L. oculatus. Genetic divergence in spotted gars is likely to be related to a combination of geographic isolation and founder effects associated with recent colonization following glacial retreat. Despite its apparent lack of significant genetic differentiation or haplotype diversity, the Great Lakes population of spotted gars has previously been shown to be a unique component of the species, and additional studies are needed to determine the genetic mechanisms underlying regional adaptations as well as potential morphological differentiation among spotted gar populations.


Asunto(s)
Distribución Animal , Peces/genética , Variación Genética , Animales , Filogeografía , Estados Unidos
8.
Clin Infect Dis ; 62 Suppl 3: S268-74, 2016 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-27118857

RESUMEN

In many settings, the dedication of healthcare workers (HCWs) to the treatment of tuberculosis exposes them to serious risks. Current ethical considerations related to tuberculosis prevention in HCWs involve the threat posed by comorbidities, issues of power and space, the implications of intersectoral collaborations, (de)professionalization, just remuneration, the duty to care, and involvement in research. Emerging ethical considerations include mandatory vaccination and the use of geolocalization services and information technologies. The following exploration of these various ethical considerations demonstrates that the language of ethics can fruitfully be deployed to shed new light on policies that have repercussions on the lives of HCWs in underresourced settings. The language of ethics can help responsible parties get a clearer sense of what they owe HCWs, particularly when these individuals are poorly compensated, and it shows that it is essential that HCWs' contribution be acknowledged through a shared commitment to alleviate ethically problematic aspects of the environments within which they provide care. For this reason, there is a strong case for the community of bioethicists to continue to take greater interest both in the micro-level (eg, patient-provider interactions) and macro-level (eg, injustices that occur as a result of the world order) issues that put HCWs working in areas with high tuberculosis prevalence in ethically untenable positions. Ultimately, appropriate responses to the various ethical considerations explored here must vary based on the setting, but, as this article shows, they require thoughtful reflection and courageous action on the part of governments, policy makers, and managers responsible for national responses to the tuberculosis epidemic.


Asunto(s)
Personal de Salud/ética , Transmisión de Enfermedad Infecciosa de Paciente a Profesional/ética , Transmisión de Enfermedad Infecciosa de Paciente a Profesional/prevención & control , Enfermedades Profesionales/prevención & control , Tuberculosis/prevención & control , Bioética , Humanos
9.
Br J Cancer ; 113(7): 1081-5, 2015 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-26402414

RESUMEN

BACKGROUND: Evidence evaluating the association between type of coffee intake (caffeinated, decaffeinated) and risk of pancreatic cancer is limited. METHODS: In the US NIH-AARP Diet and Health Study, we used Cox proportional hazards regression to estimate hazard ratios and 95% confidence intervals (CIs) for coffee intake and risk of pancreatic cancer among 457 366 US adults. RESULTS: Over 4 155 256 person-years of follow-up, 1541 incident first primary pancreatic cancers occurred. Following detailed adjustment for tobacco smoking history, risk estimates for coffee drinking were not statistically significant; compared with never drinkers of coffee, the hazard ratios (95% CI) were 1.05 (0.85-1.30), 1.06 (0.86-1.31), 1.03 (0.85-1.25), 1.00 (0.79-1.25), and 1.24 (0.93-1.65) for <1, 1, 2-3, 4-5, and ≥6 cups per day, respectively (P-value for trend 0.46). The observed null association was consistent across all examined strata (sex, smoking status, coffee caffeination, and prevalent diabetes). CONCLUSIONS: In a prospective study of coffee intake with the largest number of pancreatic cancer cases to date, we did not observe an association between total, caffeinated, or decaffeinated coffee intake and pancreatic cancer.


Asunto(s)
Café/efectos adversos , Neoplasias Pancreáticas/epidemiología , Neoplasias Pancreáticas/etiología , Anciano , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Medición de Riesgo/métodos , Factores de Riesgo , Fumar/efectos adversos , Estados Unidos/epidemiología
10.
Ann Oncol ; 26(11): 2257-66, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26347100

RESUMEN

BACKGROUND: Body mass index (BMI), a measure of obesity typically assessed in middle age or later, is known to be positively associated with pancreatic cancer. However, little evidence exists regarding the influence of central adiposity, a high BMI during early adulthood, and weight gain after early adulthood on pancreatic cancer risk. DESIGN: We conducted a pooled analysis of individual-level data from 20 prospective cohort studies in the National Cancer Institute BMI and Mortality Cohort Consortium to examine the association of pancreatic cancer mortality with measures of central adiposity (e.g. waist circumference; n = 647 478; 1947 pancreatic cancer deaths), BMI during early adulthood (ages 18-21 years) and BMI change between early adulthood and cohort enrollment, mostly in middle age or later (n = 1 096 492; 3223 pancreatic cancer deaths). Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards regression models. RESULTS: Higher waist-to-hip ratio (HR = 1.09, 95% CI 1.02-1.17 per 0.1 increment) and waist circumference (HR = 1.07, 95% CI 1.00-1.14 per 10 cm) were associated with increased risk of pancreatic cancer mortality, even when adjusted for BMI at baseline. BMI during early adulthood was associated with increased pancreatic cancer mortality (HR = 1.18, 95% CI 1.11-1.25 per 5 kg/m(2)), with increased risk observed in both overweight and obese individuals (compared with BMI of 21.0 to <23 kg/m(2), HR = 1.36, 95% CI 1.20-1.55 for BMI 25.0 < 27.5 kg/m(2), HR = 1.48, 95% CI 1.20-1.84 for BMI 27.5 to <30 kg/m(2), HR = 1.43, 95% CI 1.11-1.85 for BMI ≥30 kg/m(2)). BMI gain after early adulthood, adjusted for early adult BMI, was less strongly associated with pancreatic cancer mortality (HR = 1.05, 95% CI 1.01-1.10 per 5 kg/m(2)). CONCLUSIONS: Our results support an association between pancreatic cancer mortality and central obesity, independent of BMI, and also suggest that being overweight or obese during early adulthood may be important in influencing pancreatic cancer mortality risk later in life.


Asunto(s)
Obesidad Abdominal/mortalidad , Obesidad/mortalidad , Neoplasias Pancreáticas/mortalidad , Adolescente , Estudios de Cohortes , Humanos , Obesidad/diagnóstico , Obesidad Abdominal/diagnóstico , Neoplasias Pancreáticas/diagnóstico , Factores de Riesgo , Circunferencia de la Cintura , Adulto Joven
11.
Mol Psychiatry ; 19(6): 652-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24776741

RESUMEN

Schizophrenia is a serious psychiatric disorder with a broadly undiscovered genetic etiology. Recent studies of de novo mutations (DNMs) in schizophrenia and autism have reinforced the hypothesis that rare genetic variation contributes to risk. We carried out exome sequencing on 57 trios with sporadic or familial schizophrenia. In sporadic trios, we observed a ~3.5-fold increase in the proportion of nonsense DNMs (0.101 vs 0.031, empirical P=0.01, Benjamini-Hochberg-corrected P=0.044). These mutations were significantly more likely to occur in genes with highly ranked probabilities of haploinsufficiency (P=0.0029, corrected P=0.006). DNMs of potential functional consequence were also found to occur in genes predicted to be less tolerant to rare variation (P=2.01 × 10(-)(5), corrected P=2.1 × 10(-)(3)). Genes with DNMs overlapped with genes implicated in autism (for example, AUTS2, CHD8 and MECP2) and intellectual disability (for example, HUWE1 and TRAPPC9), supporting a shared genetic etiology between these disorders. Functionally CHD8, MECP2 and HUWE1 converge on epigenetic regulation of transcription suggesting that this may be an important risk mechanism. Our results were consistent in an analysis of additional exome-based sequencing studies of other neurodevelopmental disorders. These findings suggest that perturbations in genes, which function in the epigenetic regulation of brain development and cognition, could have a central role in the susceptibility to, pathogenesis and treatment of mental disorders.


Asunto(s)
Mutación , Esquizofrenia/genética , Adolescente , Adulto , Trastorno Autístico/genética , Ensamble y Desensamble de Cromatina/genética , Codón sin Sentido , Análisis Mutacional de ADN , Exoma , Familia , Femenino , Predisposición Genética a la Enfermedad , Haploinsuficiencia , Humanos , Discapacidad Intelectual/genética , Masculino , Persona de Mediana Edad , Adulto Joven
12.
Br J Cancer ; 111(1): 181-5, 2014 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-24786605

RESUMEN

BACKGROUND: Diabetes is a risk factor for pancreatic cancer but its association with survival from pancreatic cancer is poorly understood. Our objective was to investigate the association of diabetes with survival among pancreatic cancer patients in a prospective cohort-based study where diabetes history was ascertained before pancreatic cancer diagnosis. METHODS: We evaluated survival by baseline (1993-2001) self-reported diabetes history (n=62) among 504 participants that developed exocrine pancreatic cancer within the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. Hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality were estimated using Cox proportional hazards model, adjusted for age, sex, body mass index, race, smoking, and tumour stage (local, locally advanced, and metastatic). RESULTS: The multivariable-adjusted HR for mortality comparing participants with diabetes to those without was 1.52 (95% CI=1.14-2.04, P-value <0.01). After excluding those diagnosed with pancreatic cancer within 3 years of study enrolment, HR for mortality among those with diabetes was 1.45 (95% CI=1.06-2.00, P-value=0.02). CONCLUSIONS: Using prospectively collected data, our findings indicate that diabetes is associated with worse survival among patients with pancreatic cancer.


Asunto(s)
Diabetes Mellitus/mortalidad , Neoplasias Pancreáticas/mortalidad , Anciano , Estudios de Cohortes , Diabetes Mellitus/diagnóstico , Detección Precoz del Cáncer , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/diagnóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Análisis de Supervivencia , Estados Unidos/epidemiología
13.
Ann Oncol ; 25(6): 1106-15, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24631943

RESUMEN

Pancreatic cancer has few early symptoms, is usually diagnosed at late stages, and has a high case-fatality rate. Identifying modifiable risk factors is crucial to reducing pancreatic cancer morbidity and mortality. Prior studies have suggested that specific foods and nutrients, such as dairy products and constituents, may play a role in pancreatic carcinogenesis. In this pooled analysis of the primary data from 14 prospective cohort studies, 2212 incident pancreatic cancer cases were identified during follow-up among 862 680 individuals. Adjusting for smoking habits, personal history of diabetes, alcohol intake, body mass index (BMI), and energy intake, multivariable study-specific hazard ratios (MVHR) and 95% confidence intervals (CIs) were calculated using the Cox proportional hazards models and then pooled using a random effects model. There was no association between total milk intake and pancreatic cancer risk (MVHR = 0.98, 95% CI = 0.82-1.18 comparing ≥500 with 1-69.9 g/day). Similarly, intakes of low-fat milk, whole milk, cheese, cottage cheese, yogurt, and ice-cream were not associated with pancreatic cancer risk. No statistically significant association was observed between dietary (MVHR = 0.96, 95% CI = 0.77-1.19) and total calcium (MVHR = 0.89, 95% CI = 0.71-1.12) intake and pancreatic cancer risk overall when comparing intakes ≥1300 with <500 mg/day. In addition, null associations were observed for dietary and total vitamin D intake and pancreatic cancer risk. Findings were consistent within sex, smoking status, and BMI strata or when the case definition was limited to pancreatic adenocarcinoma. Overall, these findings do not support the hypothesis that consumption of dairy foods, calcium, or vitamin D during adulthood is associated with pancreatic cancer risk.


Asunto(s)
Productos Lácteos/efectos adversos , Dieta/efectos adversos , Neoplasias Pancreáticas/epidemiología , Estudios de Cohortes , Humanos , Modelos de Riesgos Proporcionales , Factores de Riesgo
14.
Pediatr Crit Care Med ; 15(1): 7-14, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24389708

RESUMEN

OBJECTIVE: To develop explicit criteria for patient admission in order to optimize utilization of PICU facilities in the face of increasing demand outstripping resources. SETTING: Multidisciplinary PICU in a university-affiliated referral hospital in Cape Town, South Africa. DESIGN: Retrospective description of policy development and implementation PATIENTS: All patients referred to the Paediatric Intensive Care Unit of the Red Cross War Memorial Children's Hospital. INTERVENTIONS: Development and application of admission policy. MEASUREMENTS AND MAIN RESULTS: In consultation with clinicians at the hospital, principles for utilization of PICU resources were established and then translated into specific policies for prioritization of admission of particular groups of patients. The hospital team developed and implemented: criteria for intensive care admission; prioritization for certain categories of patients (including those scheduled for elective surgery); processes for refusing intensive care admission to other categories of patients; and processes to review implementation. These criteria and procedures were made explicit to clinicians, administrators, and managers and eventually agreed to by them. It was challenging to obtain "buy-in" from all potential stakeholders in the process and also to implement such policies under conditions of high stress. CONCLUSION: Development and implementation of explicit policies for utilization of PICU resources provide a "reasonable" process for fair and equitable utilization of scarce resources. The factors that have to be considered while developing these policies may extend beyond the priorities of individual patients. Implementation is still fraught with problems. Development of explicit admission policies that consider the needs of individual patients and also the longer term development of healthcare services may enable the retention of small but essential services.


Asunto(s)
Hospitales Pediátricos/organización & administración , Unidades de Cuidado Intensivo Pediátrico/organización & administración , Unidades de Cuidado Intensivo Pediátrico/estadística & datos numéricos , Política Organizacional , Admisión del Paciente/normas , Selección de Paciente , Humanos , Unidades de Cuidado Intensivo Pediátrico/provisión & distribución , Formulación de Políticas , Guías de Práctica Clínica como Asunto , Negativa al Tratamiento , Estudios Retrospectivos , Sudáfrica
15.
Heliyon ; 10(7): e28749, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38586393

RESUMEN

Declining soil fertility particularly phosphorus deficiency, low organic carbon, moisture stress and high cost of input are factors limiting soybean yield in the Nigeria savanna. Supplementary irrigation, nutrient application and inoculation with Bradyrhizobium could increase the grain yield of soybean. We evaluated the effects of Rhizobia inoculant, phosphorus fertilization, manure, and supplementary irrigation on the nodulation and productivity of a tropical soybean variety in two locations in northern Nigeria in the 2017 and 2018 cropping seasons. The treatments consisted of five input bundles: Supplementary irrigation +17.5 kg P ha-1 + 4 t ha-1 poultry manure + nodumax inoculant (S + P + M + I); 17.5 kg P ha-1 + 4 t ha-1 poultry manure + nodumax inoculant (P + M + I); 17.5 kg P ha-1 + nodumax inoculant (P + I); 17.5 kg PP ha-1 (P); and nodumax inoculant (I). Economic analysis was done to determine the benefit-cost ratio (BCR) for each input bundle. In Kano, the input bundle S + P + M + I produced mean number of nodules that were 38, 102, 200 and 352% higher than that of input bundles P + M + I, P + I, P and I, respectively. At Lere, the application of input bundle S + P + M + I increased mean number of nodules by 33, 81, 93 and 182% over that of input bundles P + M + I, P + I, P and I, respectively. Mean grain yield in Kano was greater for input bundle S + P + M + I over P + M + I, P + I, P and I bundles by 31, 50, 64 and 223%, respectively. In Lere, grain yield for input bundle S + P + M + I was higher than that of input bundles P + M + I, P + I, P and I only, by 27, 47, 41 and 184% respectively. The input bundle P + M + I produced the highest BCR (1.4) in Kano and application only of P produced the highest BCR (1.3) in Lere. Supplementary irrigation was not found to be profitable due to the high cost of supplementary irrigation.The application of P with or without manure/inoculant is recommeded for profitable soybean production in the savannas of Nigeria.

16.
Evolution ; 78(5): 821-834, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38437861

RESUMEN

Evolutionary stasis characterizes lineages that seldom speciate and show little phenotypic change over long stretches of geological time. Although lineages that appear to exhibit evolutionary stasis are often called living fossils, no single mechanism is thought to be responsible for their slow rates of morphological evolution and low species diversity. Some analyses of molecular evolutionary rates in a handful of living fossil lineages have indicated that these clades exhibit slow rates of genomic change. Here, we investigate mechanisms of evolutionary stasis using a dataset of 1,105 exons for 481 vertebrate species. We demonstrate that two ancient clades of ray-finned fishes classically called living fossils, gars and sturgeons, exhibit the lowest rates of molecular substitution in protein-coding genes among all jawed vertebrates. Comparably low rates of evolution are observed at fourfold degenerate sites in gars and sturgeons, implying a mechanism of stasis decoupled from selection that we speculate is linked to a highly effective DNA repair apparatus. We show that two gar species last sharing common ancestry over 100 million years ago produce morphologically intermediate and fertile hybrids in the wild. This makes gars the oldest naturally hybridizing divergence among eukaryotes and supports a theoretical prediction that slow rates of nucleotide substitution across the genome slow the accumulation of genetic incompatibilities, enabling hybridization across deeply divergent lineages and slowing the rate of speciation over geological timescales. Our results help establish molecular stasis as a barrier to speciation and phenotypic innovation and provide a mechanism to explain the low species diversity in living fossil lineages.


Asunto(s)
Peces , Fósiles , Animales , Peces/genética , Genoma , Evolución Molecular , Evolución Biológica , Filogenia
17.
PLoS One ; 19(3): e0292201, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38507397

RESUMEN

Multiple studies across a variety of scientific disciplines have shown that the number of times that a paper is shared on Twitter (now called X) is correlated with the number of citations that paper receives. However, these studies were not designed to answer whether tweeting about scientific papers causes an increase in citations, or whether they were simply highlighting that some papers have higher relevance, importance or quality and are therefore both tweeted about more and cited more. The authors of this study are leading science communicators on Twitter from several life science disciplines, with substantially higher follower counts than the average scientist, making us uniquely placed to address this question. We conducted a three-year-long controlled experiment, randomly selecting five articles published in the same month and journal, and randomly tweeting one while retaining the others as controls. This process was repeated for 10 articles from each of 11 journals, recording Altmetric scores, number of tweets, and citation counts before and after tweeting. Randomization tests revealed that tweeted articles were downloaded 2.6-3.9 times more often than controls immediately after tweeting, and retained significantly higher Altmetric scores (+81%) and number of tweets (+105%) three years after tweeting. However, while some tweeted papers were cited more than their respective control papers published in the same journal and month, the overall increase in citation counts after three years (+7% for Web of Science and +12% for Google Scholar) was not statistically significant (p > 0.15). Therefore while discussing science on social media has many professional and societal benefits (and has been a lot of fun), increasing the citation rate of a scientist's papers is likely not among them.


Asunto(s)
Disciplinas de las Ciencias Biológicas , Medios de Comunicación Sociales , Humanos , Bibliometría , Factor de Impacto de la Revista
18.
Br J Cancer ; 108(5): 1168-72, 2013 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-23299536

RESUMEN

BACKGROUND: Limited epidemiological studies show inverse associations between dietary flavonoid intake and pancreatic cancer risk, but results are inconsistent and are based on few cases. We examined the association between intake of flavonoids and pancreatic cancer risk in the large, prospective National Institutes of Health-AARP Diet and Health Study Cohort. METHODS: During follow-up through 2006 (median follow-up 10.6 years), 2379 pancreatic cancer cases were identified. We used Cox proportional hazards modelling to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: We found no association between total flavonoid intake (Q5 vs Q1 HR=1.09, 95% CI: 0.96-1.24) or any flavonoid subtypes and pancreatic cancer risk. Significant interactions were not observed by age, sex, smoking status, BMI or diabetes. CONCLUSION: Our results do not support the hypothesis that flavonoids have a protective role in pancreatic cancer carcinogenesis.


Asunto(s)
Dieta , Flavonoides/administración & dosificación , Neoplasias Pancreáticas/epidemiología , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Estados Unidos/epidemiología
20.
Bioethics ; 27(6): 297-304, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23718801

RESUMEN

Widening disparities in health within and between nations reflect a trajectory of 'progress' that has 'run its course' and needs to be significantly modified if progress is to be sustainable. Values and a value system that have enabled progress are now being distorted to the point where they undermine the future of global health by generating multiple crises that perpetuate injustice. Reliance on philanthropy for rectification, while necessary in the short and medium terms, is insufficient to address the challenge of economic and other systems spinning out of control. Innovative approaches are required and it is suggested that these could best emerge from in-depth multidisciplinary research supported by endeavours to promote a 'global mind-set.'


Asunto(s)
Salud Global , Disparidades en el Estado de Salud , Justicia Social , Responsabilidad Social , Valores Sociales , Formación de Concepto , Economía , Salud Global/ética , Necesidades y Demandas de Servicios de Salud/ética , Derechos Humanos , Humanos , Internacionalidad , Inutilidad Médica/ética , Pobreza , Salud Pública/normas , Investigación , Ciencia , Justicia Social/ética
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