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1.
J Biol Dyn ; 18(1): 2390843, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39162356

RESUMEN

A population model of HIV that includes susceptible individuals not taking the pre-exposure prophylaxis (PrEP), susceptible individuals taking daily PrEP, and infected individuals is developed for casual partnerships, as well as monogamous and non-monogamous long-term partnerships. Reflecting the reality of prescription availability and usage in the U.S., the PrEP taking susceptible population is a mix of individuals designated by the CDC as high and low risk for acquiring HIV. The rate of infection for non-monogamous long-term partnerships with differential susceptibility is challenging to calculate and requires Markov chain theory to represent the movement between susceptible populations before infection. The parameters associated with PrEP initiation, suspension and adherence impact both the reproduction number of the model and the elasticity indices of the reproduction model. A multi-parameter analysis reveals that increasing adherence has the largest effect on decreasing the number of new infections.


Asunto(s)
Infecciones por VIH , Modelos Biológicos , Profilaxis Pre-Exposición , Humanos , Profilaxis Pre-Exposición/métodos , Infecciones por VIH/prevención & control , Infecciones por VIH/epidemiología , Parejas Sexuales , Cumplimiento de la Medicación/estadística & datos numéricos , Fármacos Anti-VIH/uso terapéutico , Fármacos Anti-VIH/administración & dosificación , Factores de Tiempo
2.
Math Biosci Eng ; 19(12): 11903-11934, 2022 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-36653980

RESUMEN

A model with both casual and long-term partnerships is considered with respect to the impact of a pre-exposure prophylaxis (PrEP) on the spread of HIV. We consider the effect of the effectiveness of PrEP, the rate that susceptible individuals choose to take PrEP, and compliance with the daily dose of the pre-exposure prophylaxis. The rate of infection in long-term partnerships is computed using a linearized expected value as a means for including the nonlocal effects of long-term partnerships while maintaining computational feasibility. The reproduction numbers for models with casual partnerships, long-term partnerships, and a combination of both are analytically computed and global stability of both disease-free and endemic equilibria is shown. Sensitivity and PRCC analysis results suggest that increasing the compliance among the current PrEP users is a more effective strategy in the fight against the HIV epidemic than increased coverage with poor compliance. Furthermore, an analysis of the reproduction number shows that models with either casual or monogamous long-term partnerships can reach the desired $ R_0 < 1 $ threshold for high enough levels of compliance and uptake, however, a model with both casual and monogamous long-term partnerships will require additional interventions. Methods highlighted in this manuscript are applicable to other incurable diseases or diseases with imperfect vaccines effected by long-term partnerships.


Asunto(s)
Fármacos Anti-VIH , Epidemias , Infecciones por VIH , Profilaxis Pre-Exposición , Masculino , Humanos , Homosexualidad Masculina , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Infecciones por VIH/tratamiento farmacológico , Profilaxis Pre-Exposición/métodos , Reproducción , Epidemias/prevención & control , Fármacos Anti-VIH/uso terapéutico
3.
Contemp Clin Trials Commun ; 22: 100788, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34056143

RESUMEN

OBJECTIVES: The COVID-19 pandemic has been a significant stressor worldwide and reports of psychological distress, depression, sedentary lifestyles, and overall decreased wellbeing are increasing. Yoga practices have been found to improve mental and physical health. The purpose of this randomized controlled trial is to compare Isha yoga practitioners to controls on perceived stress, resilience, wellbeing, and protection and recovery from COVID-19. Trial Design. In this prospective randomized control trial, the effects of yoga practices are being compared between seasoned yoga practitioners with two controls who are age (±3 years), gender matched, and living in the same neighborhood. METHODS: Participants will be asked to complete a series of web-based surveys at baseline, six weeks, and 12 weeks. These surveys include validated scales and objective questions on COVID-19 infection and medical history. The validated questionnaires assess stress, mood states, resilience, and overall wellbeing. Questionnaires, weekly activity diaries, and medical history, will be collected using REDCap. RESULTS: We hypothesize that routine yoga practice during the COVID-19 pandemic will reduce stress, enhance well-being, and provide protective effects against COVID-19. CONCLUSION: With the growing concern about the physical and mental impacts of COVID-19 and increased interest in alternative practices such as yogic practices, this study will contribute to the growing body of evidence about the safety and efficacy of yoga for emotional, mental, and physical health conditions.

4.
Math Biosci ; 282: 91-108, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27712990

RESUMEN

In 1992, Watts and May introduced a simple dynamical systems model of the spread of HIV based on disease transmission per partnership including the length of partnership duration. This model allowed for the treatment of concurrent partnerships, although it was hampered by the assumption of an important latent phase which generated a non-autonomous system. Subsequent models including concurrency have been based on networks, Monte Carlo, and stochastic simulations which lose a qualitative understanding of the effects of concurrency. We present a new autonomous deterministic model of the effect of concurrent sexual partnerships that allows for an analytical study of disease transmission. We incorporate the effect of concurrency through the newly derived force of infection term in a mathematical model of the transmission of HIV through sexual contact in a population stratified by sexual behavior and race/ethnicity. The model also includes variations in population mixing (partner choice) and non-uniform Highly Active Anti-Retroviral Treatment (HAART) leading to viral suppression. We use this mathematical model to understand the non-uniform spread of HIV in women who were infected through heterosexual contact. In addition, an analytical study shows the importance of continued condom use in virally suppressed MSM. Numerical simulations of the reproduction number as a function of concurrency, viral suppression level, and mixing show a reservoir of disease present in both heterosexual and MSM populations. Statistical analysis of parameter values show that viral suppression level, mixing and progression to AIDS without viral suppression have a strong correlation (either positive or negative) with the number of HIV positive women. Concurrency and assortative mixing are shown to be essential to reproduce infection levels in women, as reported by 2010 data from the Center for Disease Control (CDC).


Asunto(s)
Terapia Antirretroviral Altamente Activa , Infecciones por VIH , Disparidades en el Estado de Salud , Modelos Teóricos , Parejas Sexuales , Adulto , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/etnología , Infecciones por VIH/transmisión , Humanos
5.
Vet Pathol ; 47(3): 378-86, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20382823

RESUMEN

A novel swine-origin H1N1 influenza A virus has been identified as the cause of the 2009 influenza pandemic in humans. Since then, infections with the pandemic (H1N1) 2009 influenza virus have been documented in a number of animal species. The first known cases of lethal respiratory disease associated with pandemic (H1N1) 2009 influenza virus infection in house pets occurred in domestic cats in Oregon. A 10-year-old neutered domestic shorthair and an 8-year-old spayed domestic shorthair died shortly after developing severe respiratory disease. Grossly, lung lobes of both cats were diffusely firm and incompletely collapsed. Histologically, moderate to severe necrotizing to pyonecrotizing bronchointerstitial pneumonia was accompanied by serofibrinous exudation and hyaline membranes in the alveolar spaces. Influenza A virus was isolated from nasal secretions of the male cat and from lung homogenate of the female cat. Both isolates were confirmed as pandemic (H1N1) 2009 influenza virus by real-time reverse transcriptase polymerase chain reaction. With immunohistochemistry, influenza A viral antigen was demonstrated in bronchiolar epithelial cells, pneumocytes, and alveolar macrophages in pneumonic areas. The most likely sources of infection were people in the household with influenza-like illness or confirmed pandemic (H1N1) 2009 influenza. The 2 cases reported here provide, to the best of the authors' knowledge, the first description of the pathology and viral antigen distribution of lethal respiratory disease in domestic cats after natural pandemic (H1N1) 2009 influenza virus infection, probably transmitted from humans.


Asunto(s)
Antígenos Virales/análisis , Enfermedades de los Gatos/inmunología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Infecciones por Orthomyxoviridae/veterinaria , Neumonía Viral/veterinaria , Animales , Enfermedades de los Gatos/patología , Gatos , Brotes de Enfermedades/veterinaria , Resultado Fatal , Femenino , Pulmón/patología , Pulmón/virología , Masculino , Oregon , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/patología , Neumonía Viral/inmunología , Neumonía Viral/patología
6.
Nature ; 431(7008): 559-62, 2004 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-15457258

RESUMEN

The timing of early human dispersal to Asia is a central issue in the study of human evolution. Excavations in predominantly lacustrine sediments at Majuangou, Nihewan basin, north China, uncovered four layers of indisputable hominin stone tools. Here we report magnetostratigraphic results that constrain the age of the four artefact layers to an interval of nearly 340,000 yr between the Olduvai subchron and the Cobb Mountain event. The lowest layer, about 1.66 million years old (Myr), provides the oldest record of stone-tool processing of animal tissues in east Asia. The highest layer, at about 1.32 Myr, correlates with the stone tool layer at Xiaochangliang, previously considered the oldest archaeological site in this region. The findings at Majuangou indicate that the oldest known human presence in northeast Asia at 40 degrees N is only slightly younger than that in western Asia. This result implies that a long yet rapid migration from Africa, possibly initiated during a phase of warm climate, enabled early human populations to inhabit northern latitudes of east Asia over a prolonged period.


Asunto(s)
Arqueología , Fósiles , Hominidae/fisiología , Tecnología , Animales , Evolución Biológica , China , Emigración e Inmigración , Humanos , Dinámica Poblacional , Vertebrados
7.
Nature ; 413(6854): 413-7, 2001 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-11574886

RESUMEN

The timing of the earliest habitation and oldest stone technologies in different regions of the world remains a contentious topic in the study of human evolution. Here we contribute to this debate with detailed magnetostratigraphic results on two exposed parallel sections of lacustrine sediments at Xiaochangliang in the Nihewan Basin, north China; these results place stringent controls on the age of Palaeolithic stone artifacts that were originally reported over two decades ago. Our palaeomagnetic findings indicate that the artifact layer resides in a reverse polarity magnetozone bounded by the Olduvai and Jaramillo subchrons. Coupled with an estimated rate of sedimentation, these findings constrain the layer's age to roughly 1.36 million years ago. This result represents the age of the oldest known stone assemblage comprising recognizable types of Palaeolithic tool in east Asia, and the earliest definite occupation in this region as far north as 40 degrees N.


Asunto(s)
Evolución Biológica , Hominidae , Animales , Arqueología , China , Fósiles , Sedimentos Geológicos , Humanos , Tiempo
8.
Dev Psychobiol ; 28(7): 399-407, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8557176

RESUMEN

The response to parental separation in infant titi monkeys was evaluated. Separation from the mother for 1 hr did not elicit an adrenocortical response from the infant unless the father was also removed. Separation from the father elicited a significant elevation in adrenocortical activity even when the mother remained with the infant during the separation period. Infants showed the highest cortisol levels and vocalization rates when both parents were removed and the infant remained alone in the living cage for 1 hr. As in previous research, infants maintained higher levels of contact with the father than with the mother. The results indicate that in this monogamous New World primate, the father is the primary attachment figure for the developing infant.


Asunto(s)
Cebidae/psicología , Privación Materna , Apego a Objetos , Privación Paterna , Animales , Nivel de Alerta/fisiología , Femenino , Hidrocortisona/sangre , Masculino , Responsabilidad Parental/psicología , Medio Social , Vocalización Animal/fisiología
9.
Anesthesiol Rev ; 18(1): 31-6, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-10148879

RESUMEN

Preliminary observations have shown that fentanyl citrate, a potent narcotic, is helpful during labor without undue side effects. This randomized prospective investigation compared the patient-controlled administration of fentanyl with that of administration by nurses on request. Eighty healthy women beginning active labor (cervical dilation 4 cm) at term were assigned to receive fentanyl intravenously by either patient-controlled administration (n=37) or nurse administration on demand (n=43). Pain intensity measurements during early and late labor revealed the degree of analgesia to be the same in both groups. The delay in setting up the infusion system and the short time between requesting analgesia and vaginal delivery were limitations with self-administration. Maternal oversedation and vomiting did not occur. Neonatal naloxone therapy was used infrequently, umbilical serum levels of fentanyl were the same in both groups, and postnatal neuroadaptive testing revealed comparable results in both groups. Despite the usefulness of fentanyl during labor, administration by the patient had no advantages over administration by the nurses in significantly reducing drug use, improving pain relief, or avoiding drowsiness.


Asunto(s)
Analgesia Obstétrica/métodos , Analgesia Controlada por el Paciente/métodos , Fentanilo/administración & dosificación , Adulto , Analgesia Obstétrica/efectos adversos , Analgesia Controlada por el Paciente/efectos adversos , Puntaje de Apgar , Femenino , Humanos , Recién Nacido , Trabajo de Parto , Dolor/prevención & control , Dimensión del Dolor , Embarazo , Estudios Prospectivos
10.
Proc Soc Exp Biol Med ; 194(2): 144-8, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2112254

RESUMEN

Knowledge regarding the timing of embryonic expression of the mammalian genome is of relevance for the development of preimplantation diagnostic methods for human genetic diseases. For development of preimplantation diagnosis of lysosomal storage diseases, it will be necessary to know at which embryonic stage the genes for lysosomal enzymes are expressed. In previous studies by other investigators, it has been shown that lysosomal alpha- and beta-galactosidase and beta-glucuronidase in murine embryos increase 50- to 100-fold in activity between the two-cell and late blastocyst stage. We describe here expression of lysosomal beta-galactosidase in preimplantation ovine (two-cell through midblastocyst) and porcine (two-cell through late blastocyst) embryos. Expression of beta-galactosidase in ovine and porcine preimplantation embryos followed a similar rate of increase as that described for murine embryos. Activity of beta-galactosidase increased over 10-fold between the two- to four-cell and midblastocyst stages in ovine embryos, and 300-fold between the two- to four-cell and late blastocyst stages in porcine embryos. Activity expressed on a per cell basis was relatively constant in ovine embryos, as has been described in murine embryos, and increased approximately 5-fold on a per cell basis in porcine embryos. Activity of beta-galactosidase in ovine and porcine embryos initially was greater than 12-fold on a per cell or per embryo basis than in murine embryos evaluated. The knowledge of beta-galactosidase embryonic expression may provide the basis for preimplantation diagnosis of genetic beta-galactosidase deficiency in these species.


Asunto(s)
Blastocisto/enzimología , Galactosidasas/biosíntesis , Regulación Enzimológica de la Expresión Génica , Ovinos/embriología , Porcinos/embriología , beta-Galactosidasa/biosíntesis , Animales , Femenino , Lisosomas/enzimología , Ratones , Ovinos/genética , Porcinos/genética , beta-Galactosidasa/genética
11.
Am J Vet Res ; 45(11): 2347-50, 1984 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6151816

RESUMEN

The efficacy of an ethylenediamine dihydriodide containing salt mixture was evaluated with regard to the prevention of naturally occurring foot rot in pastured cattle. Ninety-six cattle were assigned to the treatment group and 96 were assigned to the control group. The groups were allowed consumption of salt-mineral mixtures, ad libitum, that were identical, except with respect to iodine concentration. The control group's mixture contained 0.0025% iodine and the treatment group's mixture contained 0.125% iodine (0.156% ethylenediamine dihydriodide). The incidence of foot rot was measured, as was the severity of the lesions and accompanying lameness. The incidence of foot rot in the control group (20.8%) was significantly (P less than 0.05) greater than the incidence in the treatment group (8.3%). The severity of foot rot was greater (P = 0.024) in the control calves vs the treatment calves. Total serum iodine concentrations were measured in the 2 groups on days 0, 46, and 130 of the experiment. The serum iodine values of the treatment group on day 46 (46 +/- 19.8 g/dl) and day 130 (23 +/- 12.3 g/dl) were significantly different (P less than 0.01) than the serum iodine concentrations of the control animals and the pretreatment values (day 0) of both groups. Production was measured via calf weaning weights. There were no detectable differences between the 205-day adjusted weaning weights of the calves in the control group vs the calves in the treatment group. Clinical signs of iodism were not observed in the cattle involved in this study.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Etilenodiaminas/uso terapéutico , Panadizo Interdigital/prevención & control , Animales , Bovinos , Enfermedades de los Bovinos/microbiología , Enfermedades de los Bovinos/patología , Femenino , Panadizo Interdigital/microbiología , Panadizo Interdigital/patología , Fusobacterium necrophorum/aislamiento & purificación , Cojera Animal , Masculino , Prevotella melaninogenica/aislamiento & purificación
12.
Science ; 196(4296): 1329-32, 1977 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-17831750

RESUMEN

The Parker-Levy approach to reversals of the geomagnetic field predicts meridional transitional paths of the virtual geomagnetic pole (VGP) which pass either through the site of observation or through its antipode, depending upon the site location and the sense of the polarity transition. Comparison with the most detailed transitional VGP path records presently available gives some indication of the above behavior as predicted by the Parker-Levy model. Discrepancies may be due to complexities in the distribution of cyclonic convection cells in the core not considered in the formal mathematical treatment. The predicted variation in transitional field intensity experienced at any given site also is compatible with several reported transition records.

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