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1.
Public Health ; 233: 130-136, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38875732

RESUMEN

OBJECTIVES: The efficacy and availability of contraception have changed in the last several decades; however, unintended pregnancies continue to be an issue in Australia. This study aimed to describe trends in contraception in women attending a sexual health service over 9 years. STUDY DESIGN: Repeated cross-sectional study. METHODS: Women aged 16-49 years attending Melbourne Sexual Health Centre between 2011 and 2020 were included. Women were asked what methods of contraception they currently use. Contraception were categorised into long-acting reversible contraception (LARC; e.g. intrauterine devices and implants classified as highly effective), moderately effective contraception (e.g. oral contraception pill), less effective contraception (e.g. condom and withdrawal) and no contraception, as defined by US Centers for Disease Control and Prevention guidelines. Multivariable logistic regression was used to examine the factors associated with the use of moderate-high-efficacy contraception. RESULTS: A total of 38,288 women were included with a median age of 25 (interquartile range: 22-29). Between 2011 and 2020, there was a decreasing trend in condom (63.3%-56.1%; Ptrend <0.001) and oral contraception (27.2%-20.5%; Ptrend <0.001) use, whilst there was an increasing trend in the use of LARCs: implant (4.6%-6.0%; Ptrend = 0.002) and intrauterine device (2.8%-11.8%; Ptrend <0.001). Increasing age was associated with decreased odds of using moderate-high-efficacy contraception (Ptrend <0.001). Compared with Oceanian-born women, Asian (adjusted odds ratios [aOR] = 0.63, 95% confidence interval [CI]: 0.56-0.72) and Middle Eastern-born women (aOR = 0.60, 95% CI: 0.48-0.74) had lower odds of using moderate-high-efficacy contraception, whilst European (aOR = 1.23, 95% CI:1.07-1.41) and North American-born women (aOR = 1.51, 95% CI: 1.22-1.87) had higher odds of using moderate-high-efficacy contraception. CONCLUSIONS: Between 2011 and 2020, LARC use has increased, whilst less effective contraceptives, such as condom and oral contraception, have decreased among women at Melbourne Sexual Health Centre. Further research is required to understand age and ethnic disparities in contraception methods for future family planning programmes.


Asunto(s)
Anticoncepción , Humanos , Femenino , Adulto , Estudios Transversales , Adulto Joven , Adolescente , Anticoncepción/estadística & datos numéricos , Anticoncepción/métodos , Anticoncepción/tendencias , Persona de Mediana Edad , Conducta Anticonceptiva/estadística & datos numéricos , Conducta Anticonceptiva/tendencias , Australia , Condones/estadística & datos numéricos , Victoria
2.
Phys Rev Lett ; 125(16): 164802, 2020 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-33124843

RESUMEN

We demonstrate efficient transverse compression of a 12.5 MeV/c muon beam stopped in a helium gas target featuring a vertical density gradient and crossed electric and magnetic fields. The muon stop distribution extending vertically over 14 mm was reduced to a 0.25 mm size (rms) within 3.5 µs. The simulation including cross sections for low-energy µ^{+}-He elastic and charge exchange (µ^{+}↔ muonium) collisions describes the measurements well. By combining the transverse compression stage with a previously demonstrated longitudinal compression stage, we can improve the phase space density of a µ^{+} beam by a factor of 10^{10} with 10^{-3} efficiency.

3.
AIDS Behav ; 24(3): 866-880, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31111297

RESUMEN

Gender roles and imbalances in sexual power contribute to the heightened HIV-1 risk faced by women in Sub-Saharan Africa. This has led prevention research to focus on the development of female controlled methods. Despite the design of products such as vaginal rings to be used autonomously by women, male partners and women's perceptions of relationships influence HIV prevention choices. To understand the influences that male partners and dyadic dynamics had on the use of the Dapivirine Vaginal Ring in the ASPIRE trial, this analysis of qualitative data explored the types of intimate partner relationships that women engaged in. This paper describes how partners facilitated or challenged women's ring use and how women dealt with these challenges within six different types of relationships characterized by power dynamics and commitment levels. We offer insights into how future use of female-initiated HIV prevention products can be promoted through recognition of different relationship types.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Dispositivos Anticonceptivos Femeninos/estadística & datos numéricos , Infecciones por VIH/prevención & control , Relaciones Interpersonales , Profilaxis Pre-Exposición/métodos , Pirimidinas/administración & dosificación , Parejas Sexuales/psicología , Administración Intravaginal , Adolescente , Adulto , Fármacos Anti-VIH/uso terapéutico , Ensayos Clínicos como Asunto , Femenino , VIH-1 , Humanos , Malaui , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Conducta Sexual , Sudáfrica , Uganda , Cremas, Espumas y Geles Vaginales , Zimbabwe
5.
HIV Med ; 18(2): 80-88, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27353189

RESUMEN

OBJECTIVES: Maternal HIV viral load (VL) drives mother-to-child HIV transmission (MTCT) risk but there are few data from sub-Saharan Africa, where most MTCT occurs. We investigated VL changes during pregnancy and MTCT following antiretroviral therapy (ART) initiation in Cape Town, South Africa. METHODS: We conducted a prospective study of HIV-infected women initiating ART within routine antenatal services in a primary care setting. VL measurements were taken before ART initiation and up to three more times within 7 days postpartum. Analyses examined VL changes over time, viral suppression (VS) at delivery, and early MTCT based on polymerase chain reaction (PCR) testing up to 8 weeks of age. RESULTS: A total of 620 ART-eligible HIV-infected pregnant women initiated ART, with 2425 VL measurements by delivery (median gestation at initiation, 20 weeks; median pre-ART VL, 4.0 log10 HIV-1 RNA copies/mL; median time on ART before delivery, 118 days). At delivery, 91% and 73% of women had VL ≤ 1000 and ≤ 50 copies/mL, respectively. VS was strongly predicted by time on therapy and pre-ART VL. The risk of early MTCT was strongly associated with delivery VL, with risks of 0.25, 2.0 and 8.5% among women with VL < 50, 50-1000 and > 1000 copies/mL at delivery, respectively (P < 0.001). CONCLUSIONS: High rates of VS at delivery and low rates of MTCT can be achieved in a routine care setting in sub-Saharan Africa, indicating the effectiveness of currently recommended ART regimens. Women initiating ART late in pregnancy and with high VL appear substantially less likely to achieve VS and require targeted research and programmatic attention.


Asunto(s)
Antirretrovirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Complicaciones Infecciosas del Embarazo/virología , Carga Viral , Adolescente , Adulto , Femenino , Humanos , Recién Nacido , Estudios Longitudinales , Embarazo , Estudios Prospectivos , Medición de Riesgo , Sudáfrica , Adulto Joven
6.
Am Fam Physician ; 96(6): 371-378, 2017 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-28925637

RESUMEN

Hair loss is often distressing and can have a significant effect on the patient's quality of life. Patients may present to their family physician first with diffuse or patchy hair loss. Scarring alopecia is best evaluated by a dermatologist. Nonscarring alopecias can be readily diagnosed and treated in the family physician's office. Androgenetic alopecia can be diagnosed clinically and treated with minoxidil. Alopecia areata is diagnosed by typical patches of hair loss and is self-limited. Tinea capitis causes patches of alopecia that may be erythematous and scaly and must be treated systemically. Telogen effluvium is a nonscarring, noninflammatory alopecia of relatively sudden onset caused by physiologic or emotional stress. Once the precipitating cause is removed, the hair typically will regrow. Trichotillomania is an impulse-control disorder; treatment is aimed at controlling the underlying psychiatric condition. Trichorrhexis nodosa occurs when hairs break secondary to trauma and is often a result of hair styling or overuse of hair products. Anagen effluvium is the abnormal diffuse loss of hair during the growth phase caused by an event that impairs the mitotic activity of the hair follicle, most commonly chemotherapy. Physician support is especially important for patients in this situation.


Asunto(s)
Alopecia/etiología , Alopecia/terapia , Cabello/crecimiento & desarrollo , Humanos , Anamnesis , Examen Físico , Tiña del Cuero Cabelludo/complicaciones , Tiña del Cuero Cabelludo/diagnóstico , Síndromes de Tricotiodistrofia/complicaciones , Síndromes de Tricotiodistrofia/diagnóstico , Tricotilomanía/diagnóstico , Tricotilomanía/psicología
8.
J Chem Ecol ; 42(2): 118-26, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26815170

RESUMEN

Many grass species are symbiotic with systemic, vertically-transmitted, asymptomatic Epichloë endophytic fungi. These fungi often produce alkaloids that defend the host against herbivores. We studied how environmental variables affect alkaloids in endophyte-infected tall fescue (Schedonorus phoenix) from three Northern European wild origins and the widely planted US cultivar 'Kentucky-31' (KY31). The plants were grown in identical common garden experiments in Finland and Kentucky for two growing seasons. Plants were left as controls (C) or given water (W), nutrient (N) or water and nutrient (WN) treatments. For 8-10 replications of each plant origin and treatment combination in both experiments, we analyzed ergot alkaloids, lysergic acid, and lolines. In Finland, tall fescue plants produced 50 % more ergot alkaloids compared to plants of the same origin and treatments in Kentucky. Origin of the plants affected the ergot alkaloid concentration at both study sites: the wild origin plants produced 2-4 times more ergot alkaloids than KY31, but the ergot alkaloid concentration of KY31 plants was the same at both locations. Overall lysergic acid content was 60 % higher in plants grown in Kentucky than in those grown in Finland. Nutrient treatments (N, WN) significantly increased ergot alkaloid concentrations in plants from Finland but not in plants from Kentucky. These results suggest that the success of KY31 in US is not due to selection for high ergot alkaloid production but rather other traits associated with the endophyte. In addition, the environmental effects causing variation in alkaloid production of grass-endophyte combinations should be taken into account when using endophyte-infected grasses agriculturally.


Asunto(s)
Alcaloides/análisis , Hypocreales/patogenicidad , Poaceae/química , Poaceae/microbiología
9.
J Dairy Sci ; 99(2): 1039-1046, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26709170

RESUMEN

Fifteen primiparous crossbred dairy cows that were 114±14d in milk and weighed 533±56kg were used in a replicated 5×5 Latin square to test the efficacy of a calcium montmorillonite clay, NovaSil Plus (NSP; BASF Corp., Ludwigshaven, Germany), for the reduction of aflatoxin (AF) metabolite (AFM1) in milk and the effect of NSP on milk composition. Cows were housed in a freestall barn, fed once a day and milked twice a day. The experiment consisted of five 14-d periods: d 1 through 7 were considered for data collection, and d 8 through 14 were considered a wash-out phase. In each period, cows were randomly assigned to 1 of 5 dietary treatments: (1) control (CON), consisting of a basal total mixed ration (TMR); (2) high-dose NSP diet (NSP-1%), consisting of TMR plus 230 g of NSP; (3) aflatoxin diet (AFD), consisting of the TMR plus AF challenge; (4) low-dose NSP with AF (NSP-0.5%+AFD), composed of TMR plus 115 g of NSP and AF challenge; and (5) high-dose NSP with AF (NSP-1%+AFD), consisting of TMR plus 230 g of NSP and AF challenge. The AF challenge consisted of top dressing a daily dose of 100 µg/kg estimated dry matter intake (DMI); similarly, NSP was fed at 1.0 or 0.5% of estimated DMI. Milk yield and DMI were similar across treatments averaging 21.1±1.33 kg/d and 19.7±0.56 kg/d, respectively. Concentration of milk fat, protein, and lactose were similar across treatments with averages of 4.91±0.20%, 3.85±0.10%, and 4.70±0.06%, respectively. Concentration of vitamin A averaged 0.28±0.03 µg/mL and riboflavin concentration averaged 1.57±0.13 µg/mL across treatments. The concentration of minerals in milk were similar for all treatments. Cows fed CON and NSP-1% yielded the lowest concentration of AFM1 in milk with 0.03 and 0.01±0.06 µg/L. Addition of NSP reduced milk AFM1 from 1.10±0.06 µg/L with the AF diet to 0.58 and 0.32±0.06 µg/L with the NSP-0.5%+AF and NSP-1%+AF diets, respectively. Excretion of AFM1 was reduced by NSP; mean values were 24.38, 11.86, 7.38, 0.64, and 0.23, ± 1.71 µg/d, for AFD, NSP-0.5%+AFD, NSP-1%+AFD, NSP-1%, and CON, respectively. More specifically, 1.07±0.08% of the daily AF intake was transferred to the milk of cows consuming the AFD, whereas the AF transfer rates in milk from cows that consumed the NSP-0.5%+AFD and NSP-1%+AFD were 0.52 and 0.32±0.08%. Results from this research demonstrate that feeding NSP to lactating cows is an effective method to reduce the transfer and excretion of AFM1 in milk with no negative effects on dry matter intake, milk production, and composition.


Asunto(s)
Aflatoxinas/toxicidad , Silicatos de Aluminio/química , Bentonita/farmacología , Bovinos/fisiología , Lactancia/efectos de los fármacos , Aflatoxina M1/análisis , Alimentación Animal/análisis , Animales , Calcio/farmacología , Calcio de la Dieta/metabolismo , Arcilla , Dieta/veterinaria , Suplementos Dietéticos , Ingestión de Alimentos/efectos de los fármacos , Femenino , Leche/química
10.
Dermatol Online J ; 22(11)2016 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-28329566

RESUMEN

Diffuse dermal angiomatosis of the breast (DDAB) is an uncommon ulcerative angiomatosis, which occurs in middle aged women with large pendulous breasts, a history of cigarette smoking, and risk factors for atherosclerosis. Based on its rarity, no well-defined therapeutic regimen has been elucidated. We report a case of DDAB in a woman with no history of smoking or radiographic evidence of occluded vasculature who presented with ulceration and pain-associated breast nodularity. She had a complete reproducible response to oral corticosteroids.


Asunto(s)
Angiomatosis/diagnóstico , Enfermedades de la Mama/diagnóstico , Úlcera Cutánea/diagnóstico , Angiomatosis/tratamiento farmacológico , Angiomatosis/patología , Enfermedades de la Mama/tratamiento farmacológico , Enfermedades de la Mama/patología , Femenino , Glucocorticoides/uso terapéutico , Humanos , Persona de Mediana Edad , Prednisona/uso terapéutico , Enfermedades de la Piel/diagnóstico , Enfermedades de la Piel/tratamiento farmacológico , Enfermedades de la Piel/patología , Úlcera Cutánea/tratamiento farmacológico , Úlcera Cutánea/patología
11.
Mol Psychiatry ; 19(6): 724-32, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23999524

RESUMEN

Anorexia nervosa (AN) and related eating disorders are complex, multifactorial neuropsychiatric conditions with likely rare and common genetic and environmental determinants. To identify genetic variants associated with AN, we pursued a series of sequencing and genotyping studies focusing on the coding regions and upstream sequence of 152 candidate genes in a total of 1205 AN cases and 1948 controls. We identified individual variant associations in the Estrogen Receptor-ß (ESR2) gene, as well as a set of rare and common variants in the Epoxide Hydrolase 2 (EPHX2) gene, in an initial sequencing study of 261 early-onset severe AN cases and 73 controls (P=0.0004). The association of EPHX2 variants was further delineated in: (1) a pooling-based replication study involving an additional 500 AN patients and 500 controls (replication set P=0.00000016); (2) single-locus studies in a cohort of 386 previously genotyped broadly defined AN cases and 295 female population controls from the Bogalusa Heart Study (BHS) and a cohort of 58 individuals with self-reported eating disturbances and 851 controls (combined smallest single locus P<0.01). As EPHX2 is known to influence cholesterol metabolism, and AN is often associated with elevated cholesterol levels, we also investigated the association of EPHX2 variants and longitudinal body mass index (BMI) and cholesterol in BHS female and male subjects (N=229) and found evidence for a modifying effect of a subset of variants on the relationship between cholesterol and BMI (P<0.01). These findings suggest a novel association of gene variants within EPHX2 to susceptibility to AN and provide a foundation for future study of this important yet poorly understood condition.


Asunto(s)
Anorexia Nerviosa/genética , Epóxido Hidrolasas/genética , Variación Genética , Adulto , Anorexia Nerviosa/metabolismo , Índice de Masa Corporal , Estudios de Casos y Controles , Colesterol/metabolismo , Estudios de Cohortes , Femenino , Predisposición Genética a la Enfermedad , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Psicometría , Población Blanca/genética , Adulto Joven
12.
Poult Sci ; 94(6): 1298-315, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25840963

RESUMEN

Extensive research over the last couple of decades has made it obvious that mycotoxins are commonly prevalent in majority of feed ingredients. A worldwide mycotoxin survey in 2013 revealed 81% of around 3,000 grain and feed samples analyzed had at least 1 mycotoxin, which was higher than the 10-year average (from 2004 to 2013) of 76% in a total of 25,944 samples. The considerable increase in the number of positive samples in 2013 may be due to the improvements in detection methods and their sensitivity. The recently developed liquid chromatography coupled to (tandem) mass spectrometry allows the inclusion of a high number of analytes and is the most selective, sensitive, and accurate of all the mycotoxin analytical methods. Mycotoxins can affect the animals either individually or additively in the presence of more than 1 mycotoxin, and may affect various organs such as gastrointestinal tract, liver, and immune system, essentially resulting in reduced productivity of the birds and mortality in extreme cases. While the use of mycotoxin binding agents has been a commonly used counteracting strategy, considering the great diversity in the chemical structures of mycotoxins, it is very obvious that there is no single method that can be used to deactivate mycotoxins in feed. Therefore, different strategies have to be combined in order to specifically target individual mycotoxins without impacting the quality of feed. Enzymatic or microbial detoxification, referred to as "biotransformation" or "biodetoxification," utilizes microorganisms or purified enzymes thereof to catabolize the entire mycotoxin or transform or cleave it to less or non-toxic compounds. However, the awareness on the prevalence of mycotoxins, available modern techniques to analyze them, the effects of mycotoxicoses, and the recent developments in the ways to safely eliminate the mycotoxins from the feed are very minimal among the producers. This symposium review paper comprehensively discusses the above mentioned aspects.


Asunto(s)
Micotoxicosis/veterinaria , Micotoxinas/toxicidad , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/prevención & control , Animales , Contaminación de Alimentos/análisis , Micotoxicosis/epidemiología , Micotoxicosis/microbiología , Micotoxicosis/prevención & control , Aves de Corral , Enfermedades de las Aves de Corral/microbiología , Prevalencia
13.
J Appl Toxicol ; 34(1): 40-8, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23047854

RESUMEN

Food shortages and a lack of food supply regulation in developing countries often leads to chronic exposure of vulnerable populations to hazardous mixtures of mycotoxins, including aflatoxin B(1) (AFB(1)) and fumonisin B(1) (FB(1)). A refined calcium montmorillonite clay [i.e. uniform particle size NovaSil (UPSN)] has been reported to tightly bind these toxins, thereby decreasing bioavailability in humans and animals. Hence, our objectives in the present study were to examine the ability of UPSN to bind mixtures of AFB(1) and FB(1) at gastrointestinally relevant pH in vitro, and to utilize a rapid in vivo bioassay to evaluate AFB(1) and FB(1) toxicity and UPSN efficacy. Isothermal sorption data indicated tight AFB(1) binding to UPSN surfaces at both pH 2.0 and 6.5, but substantially more FB(1) bound at pH 2.0 than 6.5. Site-specific competition occurred between the toxins when exposed to UPSN in combination. Importantly, treatment with UPSN resulted in significant protection to mycotoxin-exposed hydra maintained at pH 6.9-7.0. Hydra were exposed to FB(1), AFB(1) and FB(1) /AFB(1) combinations with and without UPSN. A toxic response over 92 h was rated based on morphology and mortality. Hydra assay results indicated a minimum effective concentration (MEC) of 20 µg ml(-1) for AFB(1), whereas the MEC for FB(1) was not reached. The MEC for co-exposure was 400 µg ml(-1) FB(1) + 10 µg ml(-1) AFB(1). This study demonstrates that UPSN sorbs both mycotoxins tightly at physiologically relevant pH levels, resulting in decreased bioavailability, and that a modified hydra bioassay can be used as an initial screen in vivo to predict efficacy of toxin-binding agents.


Asunto(s)
Aflatoxina B1/toxicidad , Silicatos de Aluminio/química , Fumonisinas/toxicidad , Hydra/efectos de los fármacos , Pruebas de Toxicidad/métodos , Aflatoxina B1/farmacocinética , Animales , Arcilla , Fumonisinas/farmacocinética , Hydra/crecimiento & desarrollo , Concentración de Iones de Hidrógeno
14.
Phys Rev Lett ; 111(5): 052501, 2013 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-23952390

RESUMEN

Neutron time-of-flight spectra from inertial confinement fusion experiments with tritium-filled targets have been measured at the National Ignition Facility. These spectra represent a significant improvement in energy resolution and statistics over previous measurements, and afford the first definitive observation of a peak resulting from sequential decay through the ground state of (5)He at low reaction energies E(c.m.) 100

15.
Nat Genet ; 14(1): 98-101, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8782828

RESUMEN

Substantial evidence links alcohol drinking and serotonin (5-HT) functioning in animals. Lowered central 5-HT neurotransmission has been found in a subgroup of alcoholics, possibly those with more aggressive, assaultive tendencies. Several rodent studies have also suggested that intact 5-HT systems are important determinants of sensitivity and/or tolerance to ethanol-induced ataxia and hypothermia. Null mutant mice lacking the 5-HT1B receptor gene (5-HT1B-/-) have been developed that display enhanced aggression and altered 5-HT release in slice preparations from some, but not all, brain areas. We characterized these mice for sensitivity to several effects of ethanol. Mutant mice drank twice as much ethanol as wild-type mice, and voluntarily ingested solutions containing up to 20% ethanol in water. Their intake of food and water, and of sucrose, saccharin and quinine solutions, was normal. Mutants were less sensitive than wild-types on a test of ethanol-induced ataxia and, with repeated drug administration, tended to develop tolerance more slowly. In tests of ethanol withdrawal and metabolism, mutants and wild-type mice showed equivalent responses. Our results suggest that the 5-HT1B receptor participates in the regulation of ethanol drinking, and demonstrate that serotonergic manipulations lead to reduced responsiveness to certain ataxic effects of ethanol without affecting dependence.


Asunto(s)
Consumo de Bebidas Alcohólicas , Receptores de Serotonina/fisiología , Consumo de Bebidas Alcohólicas/efectos adversos , Animales , Ataxia/inducido químicamente , Ataxia/fisiopatología , Ingestión de Alimentos , Etanol/efectos adversos , Etanol/farmacología , Humanos , Ratones , Ratones Noqueados , Receptor de Serotonina 5-HT1B , Receptores de Serotonina/genética , Síndrome de Abstinencia a Sustancias/fisiopatología
16.
Nat Genet ; 24(4): 403-9, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10742107

RESUMEN

The actions of corticotropin-releasing hormone (Crh), a mediator of endocrine and behavioural responses to stress, and the related hormone urocortin (Ucn) are coordinated by two receptors, Crhr1 (encoded by Crhr) and Crhr2. These receptors may exhibit distinct functions due to unique tissue distribution and pharmacology. Crhr-null mice have defined central functions for Crhr1 in anxiety and neuroendocrine stress responses. Here we generate Crhr2-/- mice and show that Crhr2 supplies regulatory features to the hypothalamic-pituitary-adrenal axis (HPA) stress response. Although initiation of the stress response appears to be normal, Crhr2-/- mice show early termination of adrenocorticotropic hormone (Acth) release, suggesting that Crhr2 is involved in maintaining HPA drive. Crhr2 also appears to modify the recovery phase of the HPA response, as corticosterone levels remain elevated 90 minutes after stress in Crhr2-/- mice. In addition, stress-coping behaviours associated with dearousal are reduced in Crhr2-/- mice. We also demonstrate that Crhr2 is essential for sustained feeding suppression (hypophagia) induced by Ucn. Feeding is initially suppressed in Crhr2-/- mice following Ucn, but Crhr2-/- mice recover more rapidly and completely than do wild-type mice. In addition to central nervous system effects, we found that, in contrast to wild-type mice, Crhr2-/- mice fail to show the enhanced cardiac performance or reduced blood pressure associated with systemic Ucn, suggesting that Crhr2 mediates these peripheral haemodynamic effects. Moreover, Crhr2-/- mice have elevated basal blood pressure, demonstrating that Crhr2 participates in cardiovascular homeostasis. Our results identify specific responses in the brain and periphery that involve Crhr2.


Asunto(s)
Sistema Cardiovascular/fisiopatología , Receptores de Hormona Liberadora de Corticotropina/deficiencia , Receptores de Hormona Liberadora de Corticotropina/genética , Estrés Fisiológico/genética , Adaptación Fisiológica/genética , Adaptación Psicológica/fisiología , Hormona Adrenocorticotrópica/sangre , Animales , Anorexia/inducido químicamente , Anorexia/genética , Sistema Cardiovascular/metabolismo , Corticosterona/sangre , Hormona Liberadora de Corticotropina/metabolismo , Hormona Liberadora de Corticotropina/farmacología , Ingestión de Alimentos/efectos de los fármacos , Ecocardiografía , Conducta Exploratoria , Femenino , Marcación de Gen , Aseo Animal , Frecuencia Cardíaca/efectos de los fármacos , Hipertensión/sangre , Hipertensión/genética , Sistema Hipotálamo-Hipofisario/metabolismo , Sistema Hipotálamo-Hipofisario/fisiopatología , Masculino , Ratones , Ratones Noqueados , Sistema Hipófiso-Suprarrenal/metabolismo , Sistema Hipófiso-Suprarrenal/fisiopatología , Receptores de Hormona Liberadora de Corticotropina/metabolismo , Urocortinas , Función Ventricular Izquierda/efectos de los fármacos
17.
J Laryngol Otol ; 137(6): 667-672, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35979640

RESUMEN

OBJECTIVES: Major haemorrhage is a rare complication after chemoradiotherapy for oropharyngeal squamous cell carcinoma. This is managed by interventional neuroradiology with endovascular embolisation of the bleeding vessel. This study aimed to describe radiological and clinical predictors of haemorrhage. METHODS: A retrospective case series was conducted of all patients with oropharyngeal squamous cell carcinomas who suffered a major haemorrhage requiring embolisation during or after treatment with chemoradiotherapy or radiotherapy alone, between 2013 and 2021, in Western Australia. RESULTS: This study included 14 patients, in two groups: haemorrhage group (n = 70) and tumour stage matched non-haemorrhage group (n = 7). Patients who haemorrhaged had a larger average transverse axial tumour size on pre-treatment computed tomography (38 mm vs 22 mm; p = 0.02) and tumours tended to involve the proximal aspect of the offending bleeding vessel. All patients who haemorrhaged developed deep cavitating or ulcerative tumour bed changes on post-treatment imaging (p < 0.0001). CONCLUSION: Tumour bed ulceration or cavitation appears to be highly predictive of haemorrhage in this patient cohort.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias Orofaríngeas , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Neoplasias Orofaríngeas/patología , Carcinoma de Células Escamosas/patología , Estudios Retrospectivos , Quimioradioterapia/efectos adversos , Hemorragia/etiología , Hemorragia/terapia , Neoplasias de Cabeza y Cuello/complicaciones
18.
Nat Commun ; 14(1): 7451, 2023 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-37978186

RESUMEN

Polar ecosystems are experiencing amongst the most rapid rates of regional warming on Earth. Here, we discuss 'omics' approaches to investigate polar biodiversity, including the current state of the art, future perspectives and recommendations. We propose a community road map to generate and more fully exploit multi-omics data from polar organisms. These data are needed for the comprehensive evaluation of polar biodiversity and to reveal how life evolved and adapted to permanently cold environments with extreme seasonality. We argue that concerted action is required to mitigate the impact of warming on polar ecosystems via conservation efforts, to sustainably manage these unique habitats and their ecosystem services, and for the sustainable bioprospecting of novel genes and compounds for societal gain.


Asunto(s)
Ecosistema , Multiómica , Biodiversidad , Predicción
19.
Reprod Domest Anim ; 47 Suppl 6: 210-4, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23279502

RESUMEN

This study identified specific changes in histone lysine methylation patterns of the feline germinal vesicle (GV) during pre-antral-to-antral follicle transition, the latter being a key interval for competence acquisition. Oocytes from adult cats were isolated from pre-antral, early (≤ 0.5 mm diameter), small (0.6-1 mm) or large (1-3.5 mm) antral follicles and immuno-stained with anti-histones H3 trimethylated at lysine 9 (H3K9me3), lysine 4 (H3K4me3), lysine 27 (H3K27me3) or H3 dimethylated at lysine 79 (H3K79me2). The vast majority of oocytes (range, 72.2-85.4%; p > 0.05) contained a GV with H3K9me3 or H3K27me3, regardless of follicular stage/size. However, the proportion of GVs with H3K4me3 or H3K79me2 was higher in early antral follicles (42.6%; p < 0.05) compared with other stages (range, 12.1-15.2%). Therefore, H3K4me3 and H3K79me2 (both known to be associated with selective gene activation) appear to be reliable markers of onset of GV competence during the pre-antral-to-antral transition phase. By contrast, H3K9me3 and H3K27me3 (both known to be related to selective gene repression) seem more linked to expression patterns during the GV stage and are less useful indicators during the entire folliculogenesis interval.


Asunto(s)
Gatos/fisiología , Histonas/metabolismo , Meiosis , Oocitos/fisiología , Animales , Femenino , Regulación de la Expresión Génica/fisiología , Metilación , Folículo Ovárico , Coloración y Etiquetado
20.
J Econ Entomol ; 105(4): 1107-14, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22928286

RESUMEN

Phosphine gas, or hydrogen phosphide (PH3), is the most common insecticide applied to durable stored products worldwide and is routinely used in the United States for treatment of bulk-stored cereal grains and other durable stored products. Research from the late 1980s revealed low frequencies of resistance to various residual grain protectant insecticides and to phosphine in grain insect species collected in Oklahoma. The present work, which used the same previously established discriminating dose bioassays for phosphine toxicity as in the earlier study, evaluated adults of nine different populations of red flour beetle, Tribolium castaneum (Herbst), and five populations of lesser grain borer, Rhyzopertha dominica (F.) collected from different geographic locations in Oklahoma. One additional population for each species was a laboratory susceptible strain. Discriminating dose assays determined eight out of the nine T. castaneum populations, and all five populations of R. dominica, contained phosphine-resistant individuals, and highest resistance frequencies were 94 and 98%, respectively. Dose-response bioassays and logit analyses determined that LC99 values were approximately 3 ppm for susceptible and 377 ppm for resistant T. castaneum, and approximately 2 ppm for susceptible and 3,430 ppm for resistant R. dominica. The most resistant T. castaneum population was 119-fold more resistant than the susceptible strain and the most resistant R. dominica population was over 1,500-fold more resistant. Results suggest a substantial increase in phosphine resistance in these major stored-wheat pests in the past 21 yr, and these levels of resistance to phosphine approach those reported for other stored-grain pest species in other countries.


Asunto(s)
Insecticidas , Fosfinas , Tribolium , Animales , Femenino , Parasitología de Alimentos , Resistencia a los Insecticidas , Masculino , Oklahoma , Triticum/parasitología
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