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1.
Clinicoecon Outcomes Res ; 16: 471-482, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38855430

RESUMEN

Background and Objectives: The 21-gene assay (the Oncotype DX Breast Recurrence Score® test) estimates the 10-year risk of distant recurrence in hormone receptor positive (HR+) and human epidermal growth factor receptor 2 negative (HER2-) early-stage breast cancer to inform adjuvant chemotherapy decisions. The cost-effectiveness of the 21-gene assay compared against standard clinical-pathological risk tools alone for HR+/HER2- early-stage breast cancer was assessed using an economic model informed by evidence from randomized controlled trials. Materials and Methods: A cost-effectiveness model consisted of a decision-tree to stratify patients according to their Recurrence Score (RS) results and the use of adjuvant chemotherapy, followed by a Markov component to estimate the long-term costs and outcomes of the chosen treatment. Distributions of patients and distant recurrence probabilities were derived from the TAILORx (N0) and RxPONDER (N1) trials. The model was evaluated from a healthcare payer and societal perspective. Endocrine therapy and chemotherapy use were informed using clinical expert opinion to reflect US clinical practice and were combined with Medicare drug costs (2021) to estimate the cost of treatment. Societal costs included lost productivity and patient out-of-pocket costs obtained from literature. Results: The Oncotype DX test generated more quality-adjusted life-years (QALYs) (N0: 0.25; N1: 0.08) at a lower cost (N0: -$13,395; N1: -$2526) compared to clinical-pathological risk alone from a societal cost perspective. The overall conclusions from the model did not change when considering a payer perspective. The main cost drivers were avoidance of distant recurrence for N0 (-$12,578), and the cost of adjuvant chemotherapy for N1 (-$2133). Lost productivity had a major impact in the societal perspective analysis (N0: -$4607; N1: -$1586). Conclusion: Adjuvant chemotherapy decisions based on the RS result led to more life year gains and lower healthcare costs (dominant) compared to using clinical-pathological risk factors alone among patients with HR+/HER2- N0 and N1 early-stage breast cancer.

2.
PLoS One ; 19(5): e0302254, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38743749

RESUMEN

The gut microbiome may affect overall cardiometabolic health. Enterolactone is an enterolignan reflective of dietary lignan intake and gut microbiota composition and diversity that can be measured in the urine. The purpose of this study was to examine the association between urinary enterolactone concentration as a reflection of gut health and blood pressure/risk of hypertension in a large representative sample from the US population. This analysis was conducted using data from the National Health and Nutrition Examination Survey (NHANES) collected from January 1999 through December 2010. Variables of interest included participant characteristics (including demographic, anthropometric and social/environmental factors), resting blood pressure and hypertension history, and urinary enterolactone concentration. 10,637 participants (45 years (SE = 0.3), 51.7% (SE = 0.6%) were female) were included in analyses. In multivariable models adjusted for demographic, socioeconomic and behavioral/environmental covariates, each one-unit change in log-transformed increase in enterolactone was associated with a 0.738 point (95% CI: -0.946, -0.529; p<0.001) decrease in systolic blood pressure and a 0.407 point (95% CI: -0.575, -0.239; p<0.001) decrease in diastolic blood pressure. Moreover, in fully adjusted models, each one-unit change in log-transformed enterolactone was associated with 8.2% lower odds of hypertension (OR = 0.918; 95% CI: 0.892, 0.944; p<0.001). Urinary enterolactone, an indicator of gut microbiome health, is inversely associated with blood pressure and hypertension risk in a nationally representative sample of U.S. adults.


Asunto(s)
4-Butirolactona , Presión Sanguínea , Hipertensión , Lignanos , Encuestas Nutricionales , Humanos , Hipertensión/epidemiología , Hipertensión/orina , Femenino , Masculino , Persona de Mediana Edad , 4-Butirolactona/análogos & derivados , 4-Butirolactona/orina , Lignanos/orina , Microbioma Gastrointestinal , Adulto , Factores de Riesgo , Estados Unidos/epidemiología
3.
Clin J Oncol Nurs ; 28(2): 157-16, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38511912

RESUMEN

BACKGROUND: The length of time from diagnosis of breast cancer to surgery has steadily increased. Consultations and tests, in addition to a lack of available counseling programs, contribute to delays. Evidence suggests that delays between diagnosis and surgery may adversely affect patients. OBJECTIVES: This article examines the effect of time from diagnosis of breast cancer to surgery by requiring nurse navigators to contact the genetic counseling office within 48 hours of the diagnosis to schedule an appointment for the patient as soon as possible. METHODS: Using a quasiexperimental design, data of time from diagnosis to surgery among patients with breast cancer were collected retrospectively preintervention (N = 30) and prospectively postintervention (N = 30). FINDINGS: Time from diagnosis to surgery decreased significantly from pre- (mean = 50.3 days, SD = 22 days) to postintervention (mean = 39 days, SD = 16 days) (t = 2.25, p = 0.03).


Asunto(s)
Neoplasias de la Mama , Asesoramiento Genético , Humanos , Femenino , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Neoplasias de la Mama/cirugía , Estudios Retrospectivos , Consejo , Derivación y Consulta
4.
Nature ; 626(7999): 505-511, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38356069

RESUMEN

Non-Abelian topological order is a coveted state of matter with remarkable properties, including quasiparticles that can remember the sequence in which they are exchanged1-4. These anyonic excitations are promising building blocks of fault-tolerant quantum computers5,6. However, despite extensive efforts, non-Abelian topological order and its excitations have remained elusive, unlike the simpler quasiparticles or defects in Abelian topological order. Here we present the realization of non-Abelian topological order in the wavefunction prepared in a quantum processor and demonstrate control of its anyons. Using an adaptive circuit on Quantinuum's H2 trapped-ion quantum processor, we create the ground-state wavefunction of D4 topological order on a kagome lattice of 27 qubits, with fidelity per site exceeding 98.4 per cent. By creating and moving anyons along Borromean rings in spacetime, anyon interferometry detects an intrinsically non-Abelian braiding process. Furthermore, tunnelling non-Abelions around a torus creates all 22 ground states, as well as an excited state with a single anyon-a peculiar feature of non-Abelian topological order. This work illustrates the counterintuitive nature of non-Abelions and enables their study in quantum devices.

5.
J Med Econ ; 26(1): 973-990, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37466220

RESUMEN

BACKGROUND AND OBJECTIVES: The Oncotype DX Breast Recurrence Score test is used to estimate distant recurrence risk of hormone receptor-positive (HR+) and human epidermal growth factor receptor 2-negative (HER2-) early-stage breast cancer and inform decisions on the use of adjuvant chemotherapy. A model-based budget impact analysis compared the Oncotype DX test in combination with clinical-pathological risk against using clinical-pathological risk alone for HR+/HER2- node-negative (N0) and node-positive (N1; 1-3 axillary lymph nodes) early-stage breast cancer patients. MATERIALS AND METHODS: Test and medical costs associated with treatment of breast cancer were assessed through a US healthcare payer perspective. Distributions of patients by Recurrence Score result and distant recurrence probabilities with chemo-endocrine and endocrine therapy were derived from the TAILORx (N0) and RxPONDER (N1) trials. Changes in budget impact were evaluated over a 5-year horizon for a 1,000,000-member hypothetical health plan. RESULTS: With the Oncotype DX test, there was an incremental budget impact of $261,067 (per member per month (PMPM): $0.004), in the N0 population, and $56,143 (PMPM: $0.001) in the N1 population over the 5-year period. The largest budget impact reduction in the N0 population was attributed to reduced breast cancer recurrence costs (incremental: -$633,457, PMPM: -$0.011), while chemotherapy sparing reduced costs in the N1 population (incremental: -$94,884, PMPM: -$0.002). CONCLUSION: The clinical benefit of using the Oncotype DX test to inform adjuvant chemotherapy decisions has been shown in multiple randomized controlled trials. This analysis demonstrated that while using the Oncotype DX test to inform adjuvant chemotherapy decisions may slightly increase US healthcare costs over an initial 5-year time horizon (driven by a cost increase in the first year with cost savings reflected in remaining 4 years), there is significant scope for cost savings when assessing beyond this period due to avoided downstream costs of distant recurrence and long-term chemotherapy adverse events. PMPM costs also remain low across all populations examined, demonstrating a close-to-neutral budget impact.


Asunto(s)
Neoplasias de la Mama , Recurrencia Local de Neoplasia , Humanos , Femenino , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/tratamiento farmacológico , Perfilación de la Expresión Génica , Quimioterapia Adyuvante , Costos de la Atención en Salud , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética
6.
J Int Soc Sports Nutr ; 20(1): 2237952, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37498180

RESUMEN

Based on review and critical analysis of the literature regarding the contents and physiological effects of coffee related to physical and cognitive performance conducted by experts in the field and selected members of the International Society of Sports Nutrition (ISSN), the following conclusions represent the official Position of the Society:(1) Coffee is a complex matrix of hundreds of compounds. These are consumed with broad variability based upon serving size, bean type (e.g. common Arabica vs. Robusta), and brew method (water temperature, roasting method, grind size, time, and equipment).(2) Coffee's constituents, including but not limited to caffeine, have neuromuscular, antioxidant, endocrine, cognitive, and metabolic (e.g. glucose disposal and vasodilation) effects that impact exercise performance and recovery.(3) Coffee's physiologic effects are influenced by dose, timing, habituation to a small degree (to coffee or caffeine), nutrigenetics, and potentially by gut microbiota differences, sex, and training status.(4) Coffee and/or its components improve performance across a temporal range of activities from reaction time, through brief power exercises, and into the aerobic time frame in most but not all studies. These broad and varied effects have been demonstrated in men (mostly) and in women, with effects that can differ from caffeine ingestion, per se. More research is needed.(5) Optimal dosing and timing are approximately two to four cups (approximately 473-946 ml or 16-32 oz.) of typical hot-brewed or reconstituted instant coffee (depending on individual sensitivity and body size), providing a caffeine equivalent of 3-6 mg/kg (among other components such as chlorogenic acids at approximately 100-400 mg per cup) 60 min prior to exercise.(6) Coffee has a history of controversy regarding side effects but is generally considered safe and beneficial for healthy, exercising individuals in the dose range above.(7) Coffee can serve as a vehicle for other dietary supplements, and it can interact with nutrients in other foods.(8) A dearth of literature exists examining coffee-specific ergogenic and recovery effects, as well as variability in the operational definition of "coffee," making conclusions more challenging than when examining caffeine in its many other forms of delivery (capsules, energy drinks, "pre-workout" powders, gum, etc.).


Asunto(s)
Rendimiento Atlético , Café , Masculino , Femenino , Humanos , Cafeína/farmacología , Rendimiento Atlético/fisiología , Ácido Clorogénico/análisis , Ejercicio Físico
7.
Endocrinology ; 164(6)2023 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-37029960

RESUMEN

In menopausal and postmenopausal women, the risk for obesity, cardiovascular disease, osteoporosis, and gut dysbiosis are elevated by the depletion of 17ß-estradiol. A diet that is high in omega-6 polyunsaturated fatty acids (PUFAs), particularly linoleic acid (LA), and low in saturated fatty acids (SFAs) found in coconut oil and omega-3 PUFAs may worsen symptoms of estrogen deficiency. To investigate this hypothesis, ovariectomized C57BL/6J and transgenic fat-1 mice, which lower endogenous omega-6 polyunsaturated fatty acids, were treated with either a vehicle or estradiol benzoate (EB) and fed a high-fat diet with a high or low PUFA:SFA ratio for ~15 weeks. EB treatment reversed obesity, glucose intolerance, and bone loss in ovariectomized mice. fat-1 mice fed a 1% LA diet experienced reduced weight gain and adiposity, while those fed a 22.5% LA diet exhibited increased energy expenditure and activity in EB-treated ovariectomized mice. Coconut oil SFAs and omega-3 FAs helped protect against glucose intolerance without EB treatment. Improved insulin sensitivity was observed in wild-type and fat-1 mice fed 1% LA diet with EB treatment, while fat-1 mice fed 22.5% LA diet was protected against insulin resistance without EB treatment. The production of short-chain fatty acids by gut microbial microbiota was linked to omega-3 FAs production and improved energy homeostasis. These findings suggest that a balanced dietary fatty acid profile containing SFAs and a lower ratio of omega-6:omega-3 FAs is more effective in alleviating metabolic disorders during E2 deficiency.


Asunto(s)
Estradiol , Ácidos Grasos Omega-3 , Ácidos Grasos , Intolerancia a la Glucosa , Femenino , Animales , Ratones , Ovariectomía , Ratones Transgénicos , Ratones Endogámicos C57BL , Intolerancia a la Glucosa/prevención & control , Estradiol/farmacología , Aceite de Coco , Microbioma Gastrointestinal , Ácido Linoleico
8.
Aging Cell ; 22(4): e13791, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36905127

RESUMEN

Enhanced exercise capacity is not only a feature of healthful aging, but also a therapy for aging patients and patients with cardiovascular disease. Disruption of the Regulator of G Protein Signaling 14 (RGS14) in mice extends healthful lifespan, mediated by increased brown adipose tissue (BAT). Accordingly, we determined whether RGS14 knockout (KO) mice exhibit enhanced exercise capacity and the role of BAT in mediating exercise capacity. Exercise was performed on a treadmill and exercise capacity was assessed by maximal running distance and work to exhaustion. Exercise capacity was measured in RGS14 KO mice and their wild types (WT), and also in WT mice with BAT transplantation from RGS14 KO mice or from other WT mice. RGS14 KO mice demonstrated 160 ± 9% increased maximal running distance and 154 ± 6% increased work to exhaustion, compared to WT mice. RGS14 KO BAT transplantation to WT mice, resulted in a reversal of phenotype, with the WT mice receiving the BAT transplant from RGS14 KO mice demonstrating 151 ± 5% increased maximal running distance and 158 ± 7% increased work to exhaustion, at three days after BAT transplantation, compared to RGS14 KO donors. BAT transplantation from WT to WT mice also resulted in increased exercise performance, but not at 3 days, but only at 8 weeks after transplantation. The BAT induced enhanced exercise capacity was mediated by (1) mitochondrial biogenesis and SIRT3; (2) antioxidant defense and the MEK/ERK pathway, and increased hindlimb perfusion. Thus, BAT mediates enhanced exercise capacity, a mechanism more powerful with RGS14 disruption.


Asunto(s)
Tejido Adiposo Pardo , Proteínas RGS , Animales , Ratones , Tejido Adiposo Pardo/metabolismo , Envejecimiento , Proteínas de Unión al GTP/metabolismo , Longevidad/genética , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas RGS/genética , Proteínas RGS/metabolismo , Transducción de Señal
9.
Med Sci Sports Exerc ; 55(8): 1392-1400, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-36924325

RESUMEN

PURPOSE: We investigated the effects of gut microbes, and the mechanisms mediating the enhanced exercise performance induced by exercise training, i.e., skeletal muscle blood flow, and mitochondrial biogenesis and oxidative function in male mice. METHODS: All mice received a graded exercise test before (PRE) and after exercise training via forced treadmill running at 60% to 70% of maximal running capacity 5 d·wk -1 for 5 wk (POST). To examine the role of the gut microbes, the graded exercise was repeated after 7 d of access to antibiotic (ABX)-treated water, used to eliminate gut microbes. Peripheral blood flow, mitochondrial oxidative capacity, and markers of mitochondrial biogenesis were collected at each time point. RESULTS: Exercise training led to increases of 60% ± 13% in maximal running distance and 63% ± 11% work to exhaustion ( P < 0.001). These increases were abolished after ABX ( P < 0.001). Exercise training increased hindlimb blood flow and markers of mitochondrial biogenesis and oxidative function, including AMP-activated protein kinase, sirtuin-1, PGC-1α citrate synthase, complex IV, and nitric oxide, all of which were also abolished by ABX treatment. CONCLUSIONS: Our results support the concept that gut microbiota mediate enhanced exercise capacity after exercise training and the mechanisms responsible, i.e., hindlimb blood flow, mitochondrial biogenesis, and metabolic profile. Finally, results of this study emphasize the need to fully examine the impact of prescribing ABX to athletes during their training regimens and how this may affect their performance.


Asunto(s)
Microbiota , Condicionamiento Físico Animal , Ratones , Masculino , Animales , Factores de Transcripción/metabolismo , Tolerancia al Ejercicio , Condicionamiento Físico Animal/fisiología , Músculo Esquelético/fisiología , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo
10.
Endocrinology ; 164(3)2023 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-36626144

RESUMEN

Obesity, cardiometabolic disease, cognitive decline, and osteoporosis are symptoms of postmenopause, which can be modeled using 4-vinylcyclohexene diepoxide (VCD)-treated mice to induce ovarian failure and estrogen deficiency combined with high-fat diet (HFD) feeding. The trend of replacing saturated fatty acids (SFAs), for example coconut oil, with seed oils that are high in polyunsaturated fatty acids, specifically linoleic acid (LA), may induce inflammation and gut dysbiosis, and worsen symptoms of estrogen deficiency. To investigate this hypothesis, vehicle (Veh)- or VCD-treated C57BL/6J mice were fed a HFD (45% kcal fat) with a high LA:SFA ratio (22.5%: 8%), referred to as the 22.5% LA diet, or a HFD with a low LA:SFA ratio (1%: 31%), referred to as 1% LA diet, for a period of 23 to 25 weeks. Compared with VCD-treated mice fed the 22.5% LA diet, VCD-treated mice fed the 1% LA diet showed lower weight gain and improved glucose tolerance. However, VCD-treated mice fed the 1% LA diet had higher blood pressure and showed evidence of spatial cognitive impairment. Mice fed the 1% LA or 22.5% LA diets showed gut microbial taxa changes that have been associated with a mix of both beneficial and unfavorable cognitive and metabolic phenotypes. Overall, these data suggest that consuming different types of dietary fat from a variety of sources, without overemphasis on any particular type, is the optimal approach for promoting metabolic health regardless of estrogen status.


Asunto(s)
Grasas de la Dieta , Ácidos Grasos , Ratones , Femenino , Animales , Aceite de Coco , Ratones Endogámicos C57BL , Grasas de la Dieta/efectos adversos , Dieta Alta en Grasa/efectos adversos , Ácido Linoleico , Homeostasis , Cognición , Estrógenos
11.
J Am Coll Health ; 71(4): 1134-1142, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34260332

RESUMEN

Objective: The first aim of this study was to examine changes in freshman college students' health-enhancing physical activity (PA) and body composition across the first semester. Secondly, this study aimed to explore the role of socio-ecological variables on these processes. Methods: A sample of 166 participants (108 females, 58 males, Mage = 18.14[.96]) completed self-report pre-and posttest data on vigorous PA (VPA), moderate-to-vigorous PA (MVPA), and body mass index (BMI). Results: The results showed a statistically significant increase in BMI, but no statistically significant changes in VPA or MVPA. The findings revealed that our socio-ecological model predicted .71, .39, and .92 percent of the end of the year VPA, MVPA, and BMI, respectively. The findings highlighted the positive role of peer support, positive motivation, and university's Recreational Services on measured healthy behaviors. Conclusions: These findings suggest a need to increase college students' VPA.


Asunto(s)
Ejercicio Físico , Estudiantes , Masculino , Femenino , Humanos , Adolescente , Estudios de Seguimiento , Universidades , Índice de Masa Corporal , Composición Corporal
12.
Can J Diabetes ; 46(8): 835-842.e1, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36088215

RESUMEN

OBJECTIVES: One-third of adults in Canada are overweight and 26.8% experience obesity. Bariatric surgery confers effective weight loss and reduces obesity-related complications, including type 2 diabetes, but remains an underutilized treatment. Our objective in this study was to determine whether a gap exists in bariatric program referrals for patients with type 2 diabetes seen in endocrinology clinics at an ambulatory tertiary care hospital in Toronto, Canada. METHODS: A retrospective chart review was conducted of 843 consecutive patients with type 2 diabetes in endocrinology clinics between January 1, 2015 and December 31, 2020. Inclusion criteria were age ≥18 years, type 2 diabetes and body mass index (BMI)>35 kg/m2. Exclusion criteria were recent active cancer, uncontrolled psychiatric disease or active substance use disorder within 6 months of the initial visit. Referrals to bariatric surgery were assessed within a 5-year follow-up period and compared with baseline referral rates from the Ontario Bariatric Network (OBN). An online survey of 48 endocrinologists in Toronto, Ontario, was also conducted to assess physician-level barriers to referral. RESULTS: The proportion of patients with class II obesity (BMI>35 kg/m2) and type 2 diabetes meeting the eligibility criteria for bariatric referral was 4.6% (n=38). A documented discussion about bariatric surgery occurred with 7 (18.0%) of these eligible patients, and 1 patient (2.6%) was referred for surgery. Aside from surgical referrals, only 2.6% of eligible patients were referred to cognitive-behavioural therapy, 36.8% were initiated on obesity pharmacotherapy and 42.1% were referred to a dietitian. Baseline OBN data demonstrated that most surgical referrals (n=6,360) were from family physicians (65.0%) and only 8.8% were from a medical specialist. Eight percent of surveyed endocrinologists reported that they discussed bariatric surgery with at least half of their eligible patients. The most frequent barrier to discussing bariatric surgery during visits was time constraints. Physicians identified that simplifying the referral process and providing bariatric surgery handouts would be helpful interventions to improve referral rates. CONCLUSIONS: Our gap analysis demonstrated a low bariatric surgery referral rate by tertiary care endocrinologists. Our study also identified a large gap in the appropriate treatment of obesity with poor utilization of behavioural, lifestyle and pharmacotherapy practices. As obesity and diabetes rates increase, better education, training and knowledge translation will be necessary to overcome weight bias and prioritize obesity management.


Asunto(s)
Cirugía Bariátrica , Diabetes Mellitus Tipo 2 , Adulto , Humanos , Adolescente , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/cirugía , Estudios Retrospectivos , Obesidad/complicaciones , Obesidad/epidemiología , Obesidad/cirugía , Ontario/epidemiología , Derivación y Consulta
13.
Cardiovasc Endocrinol Metab ; 11(2): e0263, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35441130

RESUMEN

Purpose: Naltrexone (NTX) is an opioid antagonist that can reverse the physiological effects of opioid receptors when bound. Opioid receptors have been found to play a role in cardiovascular (CV) function, and thus, binding of NTX may alter CV activity at rest and in response to acute and chronic exercise (EX). We hypothesized that opioid receptor blockade will alter the typical CV responses following acute EX. Methods: We assessed the effects of opioid receptor blockade on CV function via echocardiography in mice following an acute bout of forced swimming (FSw), a model of rodent EX. We administered opioid receptor antagonist, NTX, or saline in mice before FSw and in the absence of an FSw perturbation. Furthermore, we assessed how NTX can influence maximal EX capacity on a rodent treadmill. Results: Our data shows that NTX administration does not decrease maximal EX capacity in mice (P > 0.05). However, NTX attenuated cardiac output following FSw (FSw = 52.5 ± 2.5 ml/min vs. FSw + NTX = 32.7 ± 5.2 ml/min; P < 0.05) when compared with saline control (33.5 ± 3.8 ml/min). Further, the administration of NTX in the non-EX condition significantly (P < 0.05) reduced ejection fraction. Conclusion: These data suggest that normal opioid receptor activation is necessary for typical CV function following FSw.

14.
Rev Sci Instrum ; 92(5): 053005, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34243315

RESUMEN

Transmission electron microscopy (TEM) of vitrified biological macromolecules (cryo-EM) is limited by the weak phase contrast signal that is available from such samples. Using a phase plate would thus substantially improve the signal-to-noise ratio. We have previously demonstrated the use of a high-power Fabry-Perot cavity as a phase plate for TEM. We now report improvements to our laser cavity that allow us to achieve record continuous wave intensities of over 450 GW/cm2, sufficient to produce the optimal 90° phase shift for 300 keV electrons. In addition, we have performed the first cryo-EM reconstruction using a laser phase plate, demonstrating that the stability of this laser phase plate is sufficient for use during standard cryo-EM data collection.

15.
Urol Case Rep ; 39: 101764, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34285877

RESUMEN

Placement of foreign bodies within the urethra has intrigued urologists for years. We present the case of a 30-year-old man who had self-inserted 6 kidney beans into his urethra for sexual pleasure. Conservative attempts at removal with bedside interventions were unsuccessful. The patient required operative intervention with cystoscopy and urethral foreign body retrieval. No additional trauma was appreciated and all beans were extracted. Management of patients with a urethral foreign body can be attempted with bedside extraction, however proximal or challenging objects may require surgical extraction via either endoscopic or open approaches.

17.
Front Public Health ; 9: 779035, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35198530

RESUMEN

Despite major setbacks to its health infrastructure and health workforce capacity, Liberia began its first post-graduate training program for physicians in 2013. Specialty training in Internal Medicine, Pediatrics, General Surgery and Obstetrics and Gynecology were the four inaugural Residency programs that recruited graduates from the country's only medical school, A.M. Dogliotti College of Medicine. The Obstetrics and Gynecology residency program was designed to combat the rising maternal mortality and strengthen health systems to improve maternal care. The program adapted in the face of challenges posed by limited financial support, lack of specialist-faculty and general physician shortages and the Ebola virus outbreak. The manuscript discusses the challenges and successes of the program and demonstrates how the shortage of teaching faculty was addressed by developing a collaboration between local government and educational communities, a United States (US) academic institution and volunteers from the Global Health Service Partnership.


Asunto(s)
Ginecología , Internado y Residencia , Obstetricia , Niño , Femenino , Ginecología/educación , Humanos , Liberia , Salud Materna , Obstetricia/educación , Embarazo , Estados Unidos
18.
Physiol Behav ; 228: 113199, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33038350

RESUMEN

Endogenous opioid release has been linked to exercise. We investigated if opioid blockade following forced swimming, a common model of rodent exercise, influenced cerebral glucose metabolism in mice. PET scan was used to assess the uptake of Fludeoxyglucose (FDG-18), a marker of cerebral glucose metabolism in 19 regions of the interest in the brain following: forced swimming, an acute dose of the opioid receptor blocker naltrexone or a combination of both. Forced swimming increased glucose uptake in the cerebellum, while naltrexone + forced swimming increased glucose uptake in the hypothalamus, forebrain, septum and amygdala. This suggests that opioid blockade alters the typical pattern of cerebral glucose uptake following forced swimming in mice in certain areas of the brain.


Asunto(s)
Naltrexona , Natación , Animales , Glucosa , Ratones , Naltrexona/farmacología , Péptidos Opioides , Receptores Opioides
19.
Ecology ; 101(12): e03188, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32876942

RESUMEN

The addition of nonnative species and loss of native species has modified the composition of communities globally. Although changes in ß-diversity have been well documented, there is a need for studies incorporating multiple time periods, more than one dimension of biodiversity, and inclusion of nestedness and turnover components to understand the underlying mechanisms structuring community composition and assembly. Here, we examined temporal changes in functional dissimilarity of fish communities of the Laurentian Great Lakes and compared these changes to those of taxonomic dissimilarity by decade from 1870 to 2010. Jaccard-derived functional dissimilarity index was used to quantify changes in functional ß-diversity within communities, between all possible pairs of communities, and using a multiple-site index among all communities. ß-diversity was partitioned into components of nestedness and turnover, and changes were examined over time. Similar to patterns in taxonomic dissimilarity, each community functionally differentiated from the historical community of 1870, with Lake Superior changing the most (~24%) and Lake Ontario the least (~14%). Although communities have become taxonomically homogenized, functional ß-diversity among all communities has increased over time, indicating functional differentiation. This is likely due to functional similarity between the communities being historically high (i.e., ~88% similar in 1870). The higher taxonomic relative to functional turnover indicates that the species being replaced between communities are functionally redundant, which could occur given the harsh environmental conditions of the region and/or as a result of the recent glacial history of the region. High functional nestedness across communities reflects dispersal limitations, with smaller communities being functional subsets of large communities closer to source populations. The functional differentiation observed is likely due to nonnative species with functional traits unique to the region establishing or the loss of functionally redundant native species; however, it is important to note that patterns of homogenization were periodically observed through time. Our study demonstrates the possible factors regulating diversity in the Laurentian Great Lakes fish communities, that patterns of taxonomic and functional ß-diversity are dynamic over time and vary in the magnitude and direction of change, and that taxonomic diversity should not be used to predict changes in functional diversity.


Asunto(s)
Biodiversidad , Ecosistema , Animales , Peces , Lagos , Ontario
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