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1.
Chaos ; 33(12)2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38048254

RESUMEN

We explore the effect of some simple perturbations on three nonlinear models proposed to describe large-scale solar behavior via the solar dynamo theory: the Lorenz and Rikitake systems and a Van der Pol-Duffing oscillator. Planetary magnetic fields affecting the solar dynamo activity have been simulated by using harmonic perturbations. These perturbations introduce cycle intermittency and amplitude irregularities revealed by the frequency spectra of the nonlinear signals. Furthermore, we have found that the perturbative intensity acts as an order parameter in the correlations between the system and the external forcing. Our findings suggest a promising avenue to study the sunspot activity by using nonlinear dynamics methods.

2.
Trop Anim Health Prod ; 49(7): 1511-1516, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28707080

RESUMEN

The possible influence of the "male effect" upon reproductive outcomes of adult anestrous goats under marginal rangeland conditions and supplemented with protein-enriched Opuntia megacantha Salm-Dyck was evaluated. Reproductive variables included: estrus percentage (EST, %), estrus latency (ESL, hours), ovulation percentage (OP, %), ovulation rate (OR, units), average largest follicle at ovulation (LFO, mm), largest corpus luteum (LCL, mm), embryo number (EBN, units), and embryo implantation percentage (EIP, %). During early May, anestrous mix-breed adult goats (Criollo x Alpine-Saanen-Nubian; n = 38, 26° N) were randomly distributed to (1) Control (CC; n = 12), (2), Non-enriched Opuntia (NEO; n = 14), and (3) Protein-enriched Opuntia (PEO; n = 12). Neither LW (P > 0.05) nor BCS (P > 0.05) or any of the evaluated ovarian variables differed (P > 0.05) among treatments; EST = 89.66%, ESL = 53.66 h, OP = 70.33%, OR = 1.07 units, LFO = 4.5 mm, LCL = 9.6 mm, EBN = 0.94 embryos, and EIP = 48.66%. Irrespective of nutritional supplementation regime, all goats denoted an increased response to the male effect just in the middle of the anestrous season and managed under marginal grazing conditions during the dry season (May to June; 26° N). The use of the male effect successfully invoked neurophysiological pathways to re-activate ovarian follicular and luteal pathways during the natural anestrous season in the female goat. Yet, such successful physiological scenario was not equally exerted to promote an increased embryo implantation rate; this issue claims further consideration. Therefore, it is essential to align not only the peri-conceptional but also the peri-implantation stages to the best suited environmental conditions in the rangeland, in order to increase both reproductive and economic efficiency while promoting sustainability in those rangeland-based marginal goat production systems.


Asunto(s)
Anestro/efectos de los fármacos , Proteínas en la Dieta/metabolismo , Cabras/fisiología , Opuntia/química , Reproducción/efectos de los fármacos , Alimentación Animal/análisis , Animales , Señales (Psicología) , Dieta/veterinaria , Proteínas en la Dieta/administración & dosificación , Suplementos Dietéticos/análisis , Femenino , Masculino , Distribución Aleatoria
3.
Rev Invest Clin ; 65(5): 399-402, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24687339

RESUMEN

BACKGROUND: The detection of asymptomatic bacteriuria in preadolescent girls may be important due to its effects on subsequent pregnancies. OBJECTIVE: To describe the prevalence of asymptomatic bacteriuria in preadolescent girls and the value of the nitrite test for screening. MATERIAL AND METHODS: Cross-sectional study in girls aged 9 to 13 years. Bacteriuria was defined as the growth of > 100,000 CFU/mL in 2 consecutive urine specimens. RESULTS: Three hundred and twenty seven girls were included. Asymptomatic bacteriuria was found in 7 girls, so the prevalence was 2.1% (95% CI, 1 to 4.4%). Escherichia coli was the isolated agent in all the cases. Focused interrogatory found history of urinary symptoms in 6 girls. The utility values of the nitrite test were: sensitivity, 1; specificity, 0.9; positive likelihood ratio, 10; and negative predictive value, 1. CONCLUSIONS: The prevalence of asymptomatic bacteriuria in preadolescent girls in this Mexican study is similar to the one reported internationally; it is reasonable to consider its early detection to avoid its effects on future pregnancies. Nitrite test seems to be good for screening.


Asunto(s)
Bacteriuria/epidemiología , Infecciones por Escherichia coli/epidemiología , Escherichia coli/aislamiento & purificación , Pubertad , Adolescente , Edad de Inicio , Enfermedades Asintomáticas , Bacteriuria/diagnóstico , Bacteriuria/orina , Niño , Estudios Transversales , Diagnóstico Precoz , Infecciones por Escherichia coli/diagnóstico , Infecciones por Escherichia coli/orina , Femenino , Humanos , Tamizaje Masivo , Nitritos/orina , Nitrofurantoína/uso terapéutico , Valor Predictivo de las Pruebas , Prevalencia , Tiras Reactivas , Insuficiencia del Tratamiento
4.
Biochim Biophys Acta Mol Basis Dis ; 1869(7): 166801, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37419396

RESUMEN

Over the last years, the incidence of melanoma, the deadliest form of skin cancer, has risen significantly. Nearly half of the melanoma patients exhibit the BRAFV600E mutation. Although the use of BRAF and MEK inhibitors (BRAFi and MEKi) showed an impressive success rate in melanoma patients, durability of response remains an issue because tumor quickly becomes resistant. Here, we generated and characterized Lu1205 and A375 melanoma cells resistant to vemurafenib (BRAFi). Resistant cells (Lu1205R and A375R) exhibit higher IC50 (5-6 fold increase) and phospho-ERK levels and 2-3 times reduced apoptosis than their sensitive parents (Lu1205S and A375S). Moreover, resistant cells are 2-3 times bigger, display a more elongated morphology and have a modulation of migration capacity. Interestingly, pharmacological inhibition of sphingosine kinases, that prevents sphingosine-1-phosphate production, reduces migration of Lu1205R cells by 50 %. In addition, although Lu1205R cells showed increased basal levels of the autophagy markers LC3II and p62, they have decreased autophagosome degradation and autophagy flux. Remarkably, expression of Rab27A and Rab27B, which are involved in the release of extracellular vesicles are dramatically augmented in resistant cells (i.e. 5-7 fold increase). Indeed, conditioned media obtained from Lu1205R cells increased the resistance to vemurafenib of sensitive cells. Hence, these results support that resistance to vemurafenib modulates migration and the autophagic flux and may be transferred to nearby sensitive melanoma cells by factors that are released to the extracellular milieu by resistant cells.


Asunto(s)
Melanoma , Proteínas Proto-Oncogénicas B-raf , Humanos , Vemurafenib/farmacología , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Sulfonamidas/farmacología , Indoles/farmacología , Resistencia a Antineoplásicos/genética , Línea Celular Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Autofagia
5.
Biology (Basel) ; 12(9)2023 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-37759574

RESUMEN

The aim of this study was to evaluate the effect of the month of oocyte harvesting and the temperature-humidity index on oocyte number and quality harvested from Holstein cows and heifers, oocyte developmental competence, and total embryos produced in an area of intense ambient temperature for most of the year. A total of 5064 multiparous lactating cows and 2988 nulliparous heifers were used as oocyte donors and distributed across the months of the year. Overall, total oocytes per collection did not differ (p > 0.05) between cows (16.6 ± 2.7) and heifers (15.1 ± 1.8), but oocyte developmental competence was lower (p < 0.05) in cows (21.3 ± 5.4) than heifers (25.5 ± 4.0). For cows, the total number of oocytes harvested was two-fold higher (p < 0.05) in November than in May. For heifers, the total number of oocytes harvested was highest in April (17.19 ± 0.53) and lowest in May (10.94 ± 0.32; p < 0.05). For cows, total embryos were highest in November (2.58 ± 0.42) and lowest in August (1.28 ± 0.10; p < 0.05). Thus, taken together, these results indicate that severe heat stress impaired the number and quality of oocytes harvested from donor Holstein multiparous cows and heifers, oocyte developmental competence, and total embryos produced in this area of intense ambient temperature for most of the year.

6.
Animals (Basel) ; 11(11)2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34827891

RESUMEN

This research aimed to evaluate whether the administration of hCG at the time of removal of a progesterone device may be effective at inducing estrus and ovulations in sheep during the natural seasonal anestrous, by comparing reproductive outputs (induction and duration of estrus, follicle development, ovulation, ovulation rate, and pregnancy rates) in ewes treated with eCG or only saline solution at the time of CIDR removal. Whereas results demonstrated no response in the control non-treated group, the largest rate of narrowly synchronized estrus signs and ovulations occurred in the eCG-group. The administration of hCG was effective at inducing estrus, promote follicular growth and a delayed yet significant ovulation (>84%) on day 10 after CIDR removal; moreover, an increased embryonic implantation rate was also observed. Moreover, if the hCG ewes remain exposed to active males for some days, said strategy could be adopted, aiming to induce pregnancies by natural mating in a short period of time.

7.
Wound Repair Regen ; 18(6): 567-71, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20868385

RESUMEN

There is a fatalist perception of diabetic foot because the argument of "small-vessel disease" prevails. This is the report of a cohort study of patients facing a formal recommendation for major foot amputation to assess how many can be saved with a conventional treatment, defined as debridement, pressure alleviation, metabolic control, and antibiotics. The primary efficacy measurement was the salvage of the limb at the follow-up visit between 25 and 35 days after the first consultation. The secondary efficacy measurement was the subsequent epithelization of the ulcerative lesions, following patients for up to 270 days. The cohort consisted of 105 type 2 diabetic patients; 87 (83%) had severe lesions. A total of 71 patients (68%) required hospitalization. By the intention-to-treat analysis, 89 patients (85%) avoided major amputation. A total of 88 patients were evaluated for complete epithelization, reaching median success by day 120. Overall, 51 patients (49%) underwent minor amputations. It was concluded that there is a high rate of unnecessary major foot amputations, because a diabetic foot can be salvaged across the continuum of severity when patients receive care in a multidisciplinary wound clinic.


Asunto(s)
Pie Diabético/terapia , Terapia Recuperativa , Adulto , Anciano , Anciano de 80 o más Años , Amputación Quirúrgica/estadística & datos numéricos , Antibacterianos/uso terapéutico , Estudios de Cohortes , Desbridamiento , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
8.
Rev Invest Clin ; 62(6): 503-8, 2010.
Artículo en Español | MEDLINE | ID: mdl-21416911

RESUMEN

INTRODUCTION: The administration of parenteral infusates is a frequent intervention that is considered innocuous; moreover, the risk of this procedure which offers a direct access to the bloodstream is minimized. OBJECTIVE: To evaluate the epidemiology of nosocomial pediatric bacteremias after implementing a control program. METHODS: Analysis of pediatric bacteremias was made in 3 periods: 1) 1990-1992, prior to establishing strategies to avoid contamination of parenteral infusions; 2) 1996, the phase after establishing these strategies; and 3) 2005-2006, the recent situation in the hospital. RESULTS: The proportion of gram-negative rods isolated in blood cultures dropped from 82.9 to 35.1% (p = 0.004) during the 17-year study period. There was no significant difference in the proportion of gram-negative rods isolated from intravascular catheters. The proportion of contaminated parenteral infusions dropped from 22.2% to 0.4% (p < 0.001). DISCUSSION: The strategies established to avoid the contamination of parenteral infusions were associated with a reduction in the proportion of gram-negative rods in blood cultures, although the proportion is still higher than that in developed countries, probably related to catheter contamination. We suggest establishing similar strategies in other hospitals from developing countries.


Asunto(s)
Antibacterianos/uso terapéutico , Bacteriemia/prevención & control , Infecciones Relacionadas con Catéteres/prevención & control , Infección Hospitalaria/prevención & control , Hospitales Generales/estadística & datos numéricos , Hospitales de Enseñanza/estadística & datos numéricos , Control de Infecciones/métodos , Antibacterianos/administración & dosificación , Bacteriemia/epidemiología , Bacteriemia/microbiología , Bacteriemia/transmisión , Infecciones Relacionadas con Catéteres/epidemiología , Infecciones Relacionadas con Catéteres/transmisión , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Infección Hospitalaria/transmisión , ADN Bacteriano/genética , Brotes de Enfermedades , Electroforesis en Gel de Campo Pulsado , Infecciones por Bacterias Gramnegativas/epidemiología , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/prevención & control , Infecciones por Bacterias Gramnegativas/transmisión , Infecciones por Bacterias Grampositivas/epidemiología , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/prevención & control , Infecciones por Bacterias Grampositivas/transmisión , Hospitales Generales/organización & administración , Hospitales de Enseñanza/organización & administración , Humanos , Control de Infecciones/organización & administración , Infusiones Intravenosas , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/prevención & control , Infecciones por Klebsiella/terapia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/aislamiento & purificación , México/epidemiología , Evaluación de Programas y Proyectos de Salud , Estudios Retrospectivos
9.
Dental Press J Orthod ; 25(2): 61-68, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32490922

RESUMEN

INTRODUCTION: Facial asymmetry associated with unilateral condylar hyperplasia (UCH) is a complicated clinical condition. OBJECTIVE: The objective of this study was to describe morphological characteristics of the mandible and the temporomandibular joint in patients with facial asymmetry, using computed tomography and 3D reconstruction. METHODS: A retrospective observational study was performed with patients displaying facial asymmetry evaluated by single photon emission computed tomography (SPECT)/CT analysis, for suspected UCH, between 2015 and 2018. The following variables were compared between the affected side (producing the asymmetry) and the contralateral side (side to where the jaw is deflected): condylar length, condylar medial and lateral pole length, mandibular ramus length, intra-articular spaces, articular eminence height and position of the posterior wall of the glenoid fossa. RESULTS: Forty-three patients (21 women, mean age: 20.7 ± 7.25 years) with facial asymmetry were included, 19 patients presented right side deviation and 24 patients had left side deviation. Condylar length, lateral pole length, the sum of maximum values and articular eminence height were greater in the affected side (p< 0.05). A positive correlation was found between the position of the posterior wall of the glenoid fossa and the articular eminence height in the affected side (r = 0.442). CONCLUSIONS: In patients with suspected UCH, evaluated through CT, craniofacial measurements showed significantly larger condylar length and the condylar sum of maximum values in the affected side. A positive correlation was found between the increased dimensions of the articular eminence and the more posterior position of the glenoid fossa in the affected side.


Asunto(s)
Mandíbula , Cóndilo Mandibular , Adolescente , Adulto , Asimetría Facial , Femenino , Humanos , Hiperplasia , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Adulto Joven
10.
Biology (Basel) ; 9(10)2020 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-32987953

RESUMEN

Seasonal reproduction restricts the offering of goat commodities across the year. Therefore, it is crucial to improve diverse strategies to induce the reproductive response in goats during the anestrus stage. The effectiveness of a short P4 + eCG-based estrus induction protocol during both the deep anestrous (March) or the reproductive transition period (June) upon the reproductive performance of crossbred dairy goats was assessed. Adult, anestrous, 24-30-month- old dairy crossbred (Saanen-Alpine-Nubian × Criollo) goats (n = 123) from two commercial herds and 10 sexually active goat bucks were used. Before the trials, the anestrous status of goats was confirmed. Then, goats were randomly allocated into two different experiments. In Exp. 1, we tested the effect of different doses (D) of intramuscular progesterone (P4; 10 or 20 mg + eCG (100 UI)) and type of breeding (TB), natural mating (NM), or artificial insemination (AI), on two commercial goat herds (H1 & H2), in March (deep anestrous). In Exp. 2, we evaluated the effect of D (P4; 10 or 20 mg + 100 UI eCG) in goats subjected to NM, and either during deep anestrous (March; M) or transitional anestrous (June; J), in two commercial herds. After breeding, conception and pregnancy were diagnosed with ultrasound scanning. The response variables were estrus induction (EI; %), estrus latency (EL; h), ovulation (OVP; %), ovulation rate (OR; units), fertility (FERT; %), and pregnancy (PREG; %). No differences (p > 0.05) in live weight (LW) and body condition score (BCS) occurred between herds in both trials. In Exp. 1, EI, EL, OVP, OR, FERT, and PREG were affected (p < 0.05) by the H-TB-D interaction, whereas in H1 + P4-20 combination had the highest (p < 0.05) EI, EL, and OVP values. Irrespective of TB, H1 had the largest (p < 0.05) OR, independently of TB or D. Also, the lowest (p < 0.05) OVP occurred in the AI + P4-10 group, while the AI had the lowest (p < 0.05) FERT, irrespective of D. FERT and PREG were two-fold higher (p < 0.05) in NM compared with AI. In Exp. 2, EI, EL, OVP, OR, FERT, and PREG were affected (p < 0.05) by the H-M-D interaction. In general, H2 + P4-10 had the lowest (p < 0.05) reproductive outcomes in March, whereas H1 had the largest (p < 0.05) values in either month. No differences (p > 0.05) between P4 doses occurred for EI, OVP, OR, FERT, and PREG. Yet, the largest (p < 0.05) EL occurred with P4-20 in June. No correlations (p > 0.05) occurred between LW and all the reproductive variables. BCS was positively correlated (p < 0.05) with EI (0.34), OVP (0.44), OR (0.58), and PREG (0.20). Also, positive correlations (p < 0.05) occurred between EI with EL (0.83), OVP (0.80), OR (0.64), and PREG (0.56); EL with OVP (0.58), OR (0.44), and PREG (0.42); OVP with OR (0.79) and PREG (0.70), as well as OR and PREG (0.63). Results of these studies confirm a multidimensional response regarding the effectiveness of P4 + eCG for estrus induction in goats mainly modulated by a specific time within the anestrous season, or even by specific management or a particular environment at the herd level (H1), although quite remarkably independent of the animal's LW or BCS at herd level. Moreover, the best reproductive outcomes occurred with NM in June. The most reproductive variables were similar using either 10 or 20 mg P4 + 100 IU eCG, giving the possibility to lessen the scale in the use of exogenous hormones while obtaining acceptable out of season reproductive response.

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