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1.
bioRxiv ; 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38293111

RESUMEN

Alphaviruses encode an error-prone RNA-dependent RNA polymerase (RdRp), nsP4, required for genome synthesis, yet how the RdRp functions in the complete alphavirus life cycle is not well-defined. Previous work using chikungunya virus (CHIKV) has established the importance of the nsP4 residue cysteine 483 in maintaining viral genetic fidelity. Given the location of residue C483 in the nsP4 palm domain, we hypothesized that other residues within this domain and surrounding subdomains would also contribute to polymerase function. To test this hypothesis, we designed a panel of nsP4 variants via homology modeling based on the Coxsackievirus B3 3 polymerase. We rescued each variant in both mammalian and mosquito cells and discovered that the palm domain and ring finger subdomain contribute to polymerase host-specific replication and genetic stability. Surprisingly, in mosquito cells, these variants in the ring finger and palm domain were replication competent and produced viral structural proteins, but they were unable to produce infectious progeny, indicating a yet uncharacterized role for the polymerase in viral assembly. Finally, we have identified additional residues in the nsP4 palm domain that influence the genetic diversity of the viral progeny, potentially via an alteration in NTP binding and/or discrimination by the polymerase. Taken together, these studies highlight that distinct nsP4 subdomains regulate multiple processes of the alphavirus life cycle, placing nsP4 in a central role during the switch from RNA synthesis to packaging and assembly.

2.
Radiography (Lond) ; 29(6): 975-979, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37572571

RESUMEN

INTRODUCTION: The purpose of our study was to compare the performance of 2D (FFDM) against 3D (FFDM plus DBT) examinations in the post-treatment surveillance of asymptomatic breast cancer survivors. METHODS: A list of women with a history of breast cancer who underwent screening mammography (2D or 3D) from 5/2017 to 5/2020 was retrieved. A total of 20,210 examinations were identified and performance metrics were compared. RESULTS: There were no statistically significant difference in cancer detection rate (CDR) (p = 0.38), recall rate (RR) (p = 0.087), or positive predictive value (PPV) (p = 0.74) between 2D vs. 3D examinations. Stratification by breast tissue identified no statistically significant difference in CDR (p = 0.581 and p = 0.428), RR (p = 0.230 and p = 0.205), or PPV (p = 0.908 and p = 0.721) between fatty/scattered and heterogeneous/extremely dense breast tissue when comparing 2D vs 3D examinations. Stratification by age did not identify a significant difference in RR or PPV between the two groups. CDR was statistically increased with 2D vs. 3D examinations in the 60-69 years group (p = 0.021). Stratification by race did not identify a significant difference in RR or PPV between the two groups. CDR was statistically increased with 3D vs. 2D examinations in white women (p = 0.036). Stratification by laterality (bilateral vs. unilateral post mastectomy) did not identify a significant difference in RR or PPV between the two groups. CDR was statistically increased in 2D vs. 3D examinations in unilateral studies (p = 0.009). CONCLUSION: For asymptomatic women with a history of breast cancer, there is no evidence that the addition of DBT to FFDM improves CDR, RR, or PPV. IMPLICATIONS FOR PRACTICE: More studies are needed concerning screening methodologies supplementing FFDM in the screening regimens of breast cancer survivors.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/diagnóstico , Mamografía/métodos , Estudios Retrospectivos , Densidad de la Mama , Tamizaje Masivo , Detección Precoz del Cáncer/métodos , Mastectomía
3.
Evol Appl ; 15(12): 2125-2141, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36540646

RESUMEN

Numerous terrestrial mammal species have experienced extensive population declines during past centuries, due largely to anthropogenic pressures. For some species, including the Eurasian otter (Lutra lutra), environmental and legal protection has more recently led to population growth and recolonization of parts of their historic ranges. While heralded as conservation success, only few such recoveries have been examined from a genetic perspective, i.e. whether genetic variability and connectivity have been restored. We here use large-scale and long-term genetic monitoring data from UK otters, whose population underwent a well-documented population decline between the 1950s and 1970s, to explore the dynamics of a population re-expansion over a 21-year period. We genotyped otters from across Wales and England at five time points between 1994 and 2014 using 15 microsatellite loci. We used this combination of long-term temporal and large-scale spatial sampling to evaluate 3 hypotheses relating to genetic recovery that (i) gene flow between subpopulations would increase over time, (ii) genetic diversity of previously isolated populations would increase and that (iii) genetic structuring would weaken over time. Although we found an increase in inter-regional gene flow and admixture levels among subpopulations, there was no significant temporal change in either heterozygosity or allelic richness. Genetic structuring among the main subpopulations hence remained strong and showed a clear historical continuity. These findings highlight an underappreciated aspect of population recovery of endangered species: that genetic recovery may often lag behind the processes of spatial and demographic recovery. In other words, the restoration of the physical connectivity of populations does not necessarily lead to genetic connectivity. Our findings emphasize the need for genetic data as an integral part of conservation monitoring, to enable the potential vulnerability of populations to be evaluated.

4.
J Craniofac Surg ; 33(7): 2005-2010, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36201697

RESUMEN

The evolution of virtual surgical planning (VSP) in the last 2 decades has led to improved precision and efficiency for orthognathic surgery, both pre- and intraoperatively. This study evaluates a single surgeon's experience with this technology over the past 6 years. Patients undergoing orthognathic surgery using VSP with the senior author between 2015 and 2021 were retrospectively reviewed. Virtual surgical planning -specific data including incidence of midline/cant correction, occlusal equilibration, serial splints, segmental osteotomies, and custom plates were recorded and analyzed. Sixty patients undergoing orthognathic surgery using simulated VSP in the study period were retrospectively reviewed. Mean age at time of surgery was 23.5±7.9 years. Forty-nine patients (81.7%) underwent LeFort I osteotomy combined with at least 1 additional procedure (eg,unilateral or bilateral sagittal split osteotomy, condylectomy, genioplasty, etc.). Twenty-six (43.3%) of patients in the studied cohort underwent maxillary midline correction, 30.0% required occlusal equilibration, 36.7% underwent maxillary molar cant correction, 30.0% underwent mandibular cant correction, and 21.7% required both maxillary and mandibular cant correction. Three patients required serial splinting, and 15 patients (25.0%) required modification of splint design. Custom plates were utilized in 15 patients (25.0%). This study demonstrates the utility of VSP in accurately detecting occlusal cants, asymmetry, and occlusal interferences. Virtual surgical planning also allows for a dynamic preoperative planning process, offering the surgeon a high degree of versatility in splint design, and the ability to fabricate multiple customized splints for each case. This is particularly useful in patients with limited or unpredictable soft tissue elasticity.


Asunto(s)
Cirugía Ortognática , Procedimientos Quirúrgicos Ortognáticos , Cirujanos , Cirugía Asistida por Computador , Adolescente , Adulto , Humanos , Ferulas Oclusales , Procedimientos Quirúrgicos Ortognáticos/métodos , Estudios Retrospectivos , Cirugía Asistida por Computador/métodos , Adulto Joven
5.
J Mammal ; 98(5): 1310-1329, 2017 10 03.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29674786

RESUMEN

An allopatric population of big-eared climbing rats (Ototylomys) from the Northern Highlands of Chiapas, Mexico, is described as a new species. The new taxon is part of a unique montane rainforest community that includes several other endemic species in the limited geographic range between the Río Grijalva and the Central Depression of Chiapas. Several cranial, external, and molecular characters distinguish this new species of big-eared climbing rat from its more widely distributed congener, Ototylomys phyllotis. We performed principal component and discriminate function analyses of cranial measurements, and found that specimens of the new species consistently could be distinguished from other Ototylomys with strong statistical support. Compared with exemplars of Ototylomys from elsewhere in their range, the new species possesses a karyotype that differs by 3 additional biarmed chromosome pairs, is fixed or nearly fixed for distinct electromorphs at 12 allozyme loci, and the mean genetic distance exceeds 14%, based on comparisons of the mitochondrial cytochrome b gene between the new species of Ototylomys and representatives of O. phyllotis. The restricted distribution in montane karst rainforest suggests that the species and its habitat may be a matter of conservation concern.


Una población alopátrica de rata orejuda trepadora (Ototylomys) de las Tierras Altas del Norte de Chiapas, México se describe como una nueva especie. El nuevo taxón es parte de una comunidad única de bosque lluvioso montano que incluye varias especies endémicas en el área de distribución geográfica limitada entre el Río Grijalva y la Depresión Central de Chiapas. Varios caracteres craneales, externos, y moleculares distinguen la nueva rata orejuda trepadora de su congénere más ampliamente distribuido, Ototylomys phyllotis. Se realizaron análisis de componentes principales y de función discriminante de los caracteres craneales, y se encontró que los especímenes de La Pera fueron consistentemente distinguidos de otros Ototylomys con un fuerte soporte estadístico. En comparación con ejemplares de Ototylomys del rango, la nueva especie posee un cariotipo que difiere por 3 pares adicionales de cromosomas biarmados, está fijo o casi fijo por distintos electromorfos en 12 loci alozímicos. Adicionalmente, la media de la distancia genética comparada del gen mitochondrial citocromo b entre la nueva especie de Ototylomys y representantes de O. phyllotis, excede el 14%. La distribución restringida en el bosque lluvioso montano kárstico sugiere que la especie y su hábitat pueden ser de importancia para la conservación.

6.
J Mycol Med ; 24(2): 112-6, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24746726

RESUMEN

OBJECTIVE: Candida albicans is one of the main causes of vaginitis, especially in women with recurrent episodes. The appearance of drug resistant C. albicans and adverse effects of chemical agents have raised interest in Echinophora platyloba as one of four native species in Traditional Persian-Iranian medicine. MATERIALS AND METHODS: This study evaluates the antifungal activity of ethanolic extract from dried aerial parts of E. platyloba against 27 clinical isolates of C. albicans from women suffering chronic recurrent vaginitis by micro-broth dilution assay. The synergistic effect of azole drugs and E. platyloba ethanolic extract were also determined by disc diffusion method after determining the MIC90. RESULTS: The results of this study showed a potent synergistic effect of E. platyloba ethanolic extract and itraconazole (P<0.01) and fluconazole (P<0.001) but an antagonistic effect between E. platyloba ethanolic extract and clotrimazole and miconazole against clinical isolates of C. albicans. CONCLUSION: These results must be confirmed by clinical application and by further clinical studies.


Asunto(s)
Antifúngicos/farmacología , Azoles/farmacología , Candida albicans/efectos de los fármacos , Candidiasis Vulvovaginal/microbiología , Extractos Vegetales/farmacología , Candida albicans/aislamiento & purificación , Candidiasis Vulvovaginal/tratamiento farmacológico , Enfermedad Crónica , Sinergismo Farmacológico , Etanol/química , Femenino , Humanos , Irán , Medicina Tradicional , Pruebas de Sensibilidad Microbiana , Recurrencia
7.
J Assist Reprod Genet ; 29(4): 365-71, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22183502

RESUMEN

PURPOSE: Sperm that bypass natural apoptosis and the ubiquitin-proteasome system may find their way into semen. In order to avoid the insemination of such sperm during an intracytoplasmic sperm injection (ICSI) treatment, novel sperm selection procedures such as the Zeta procedure have been implemented. Therefore, the aim of this study was to evaluate extent of ubiquitination and external phosphatidylserine (EPS) in sperm populations selected by combines density gradient centrifugation (DGC) and Zeta electric potential in comparison to DGC and neat semen samples. METHODS: Semen samples were collected from 51 infertile men and divided into control, DGC and DGC-Zeta groups. Semen analysis was carried out according to World Health Organization criteria. The percentages of protamine deficiency, DNA fragmentation, EPS and ubiquitinated sperm were assessed by chromomycin A3 (CMA3), TUNEL, Annexin V, and immunostaining, respectively. RESULTS: Sperm selected by the DGC-Zeta procedure presented a lower percentage of sperm with protamine deficiency, abnormal morphology and DNA fragmentation while the percentage of annexin V and ubiquitin-positive sperm increased. CONCLUSION: The results of this study reveal that, DGC-Zeta improves the quality of the selected spermatozoa for ICSI and increases ubiquitination and EPS rates. We propose these alterations are part of the normal physiological process of capacitation.


Asunto(s)
Anexina A5/metabolismo , Centrifugación por Gradiente de Densidad/métodos , Espermatozoides/metabolismo , Ubiquitina/metabolismo , Ubiquitinación , Cromomicina A3/análisis , Fragmentación del ADN , Humanos , Infertilidad Masculina/metabolismo , Masculino , Fosfatidilserinas/análisis , Protaminas/análisis , Semen/metabolismo , Inyecciones de Esperma Intracitoplasmáticas/métodos , Espermatozoides/fisiología
8.
J Anim Physiol Anim Nutr (Berl) ; 94(5): 628-34, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20050956

RESUMEN

Our objective was to study the relationships between colostral somatic cell counts (SCC, a criterion for mastitis severity at parturition) and early calf growth, blood indicators of immunity, and pre-weaning faecal and health states. Sixty-nine Holstein cows were assigned to three groups of greater (n = 21, 5051 × 10(3)), medium (n = 38, 2138 × 10(3)) and lower (n = 10, 960 × 10(3)) colostral SCC (per ml) in a completely randomized design. Calves received 2 l of colostrum on day 1, and jugular blood was sampled at birth, at 3 h after the first colostrum feeding and at 42 days of age for immunoglobulin G (IgG) measurements. Calves were fed transition milk from their dams until 3 days of age and whole milk from 4 to 60 days of age twice daily at 10% of body weight. Health status and faecal physical scores were recorded daily for 42 days. Increased colostral SCC was associated with increased serum IgG at parturition. Colostral pH increased and fat percentage decreased linearly with the rising SCC. Feeding colostrum with greater SCC was associated with reduced serum IgG concentrations at 3 h after first colostrum feeding, greater incidences of diarrhoea and compromised health status during the first 42 days of age, and reduced weaning weight gain, but had no effects on calf body length and withers height. Colostral volume and percentages of protein, lactose, solids-non-fat, total solids and IgG were comparable among groups. Results suggest a role for SCC, as an indicator of mastitis and colostral health quality, in affecting calf health. As a result of the novelty of calf health dependence on colostral SCC found, future studies to further characterize such relationships and to uncover or rule out possible mediators are required before colostral SCC could be recommended for routine on-farm use in managing dry cow and calf production.


Asunto(s)
Bovinos/crecimiento & desarrollo , Bovinos/inmunología , Calostro/citología , Animales , Femenino , Concentración de Iones de Hidrógeno , Inmunoglobulina G/sangre , Mastitis Bovina/patología , Destete
9.
Forensic Sci Int ; 154(2-3): 224-39, 2005 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-16182971

RESUMEN

The work described in this report was focused on generating increased knowledge of fingerprint chemistry, particularly the composition of a latent fingerprint at the time it is deposited, and the chemical changes in lipid components that occur over time. Fingerprints from five male donors (aged 25-34 years) were collected and aged under controlled conditions. The prints were then sampled at set intervals, solvent extracted with dichloromethane, co-derivatized with MSTFA and analyzed by gas chromatography-mass spectrometry (GC-MS). It was shown that there was loss of squalene from prints stored in the light or in the dark. Loss was more rapid in the light, with squalene in prints from some donors not detected after 9 days storage. For these same donors, squalene was still detected after 33 days storage in the dark, but at much lower levels than in fresh prints. For saturated fatty acids (tetradecanoic, palmitic and stearic acid) there was a trend towards an increase in levels of these substances during storage (up to about 20 days) followed by a decrease back to original levels or below. This was the case for samples stored in the light or in the dark. For palmitoleic acid, a similar trend was seen. For oleic acid, this trend was seen for samples stored in the dark. For samples stored in the light the general trend was a decrease in level over the storage period (up to 33 days).


Asunto(s)
Dermatoglifia , Ácidos Grasos/análisis , Adulto , Oscuridad , Cromatografía de Gases y Espectrometría de Masas , Humanos , Luz , Masculino , Manejo de Especímenes , Escualeno/análisis
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