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1.
Mol Hum Reprod ; 29(3)2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36688722

RESUMEN

Spermatogonial stem cells (SSCs) are the basis of spermatogenesis, a complex process supported by a specialized microenvironment, called the SSC niche. Postnatal development of SSCs is characterized by distinct metabolic transitions from prepubertal to adult stages. An understanding of the niche factors that regulate these maturational events is critical for the clinical application of SSCs in fertility preservation. To investigate the niche maturation events that take place during SSC maturation, we combined different '-omics' technologies. Serial single cell RNA sequencing analysis revealed changes in the transcriptomes indicative of niche maturation that was initiated at 11 years of age in humans and at 8 weeks of age in pigs, as evident by Monocle analysis of Sertoli cells and peritubular myoid cell (PMC) development in humans and Sertoli cell analysis in pigs. Morphological niche maturation was associated with lipid droplet accumulation, a characteristic that was conserved between species. Lipidomic profiling revealed an increase in triglycerides and a decrease in sphingolipids with Sertoli cell maturation in the pig model. Quantitative (phospho-) proteomics analysis detected the activation of distinct pathways with porcine Sertoli cell maturation. We show here that the main aspects of niche maturation coincide with the morphological maturation of SSCs, which is followed by their metabolic maturation. The main aspects are also conserved between the species and can be predicted by changes in the niche lipidome. Overall, this knowledge is pivotal to establishing cell/tissue-based biomarkers that could gauge stem cell maturation to facilitate laboratory techniques that allow for SSC transplantation for restoration of fertility.


Asunto(s)
Células de Sertoli , Nicho de Células Madre , Humanos , Masculino , Adulto , Animales , Porcinos , Lactante , Células de Sertoli/metabolismo , Multiómica , Espermatogonias , Espermatogénesis/fisiología , Testículo/metabolismo
2.
J Gen Intern Med ; 37(14): 3545-3553, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35088201

RESUMEN

BACKGROUND: Multimorbidity (≥ 2 chronic diseases) is associated with greater disability and higher treatment burden, as well as difficulty coordinating self-management tasks for adults with complex multimorbidity patterns. Comparatively little work has focused on assessing multimorbidity patterns among patients seeking care in community health centers (CHCs). OBJECTIVE: To identify and characterize prevalent multimorbidity patterns in a multi-state network of CHCs over a 5-year period. DESIGN: A cohort study of the 2014-2019 ADVANCE multi-state CHC clinical data network. We identified the most prevalent multimorbidity combination patterns and assessed the frequency of patterns throughout a 5-year period as well as the demographic characteristics of patient panels by prevalent patterns. PARTICIPANTS: The study included data from 838,642 patients aged ≥ 45 years who were seen in 337 CHCs across 22 states between 2014 and 2019. MAIN MEASURES: Prevalent multimorbidity patterns of somatic, mental health, and mental-somatic combinations of 22 chronic diseases based on the U.S. Department of Health and Human Services Multiple Chronic Conditions framework: anxiety, arthritis, asthma, autism, cancer, cardiac arrhythmia, chronic kidney disease (CKD), chronic obstructive pulmonary disease (COPD), congestive heart failure, coronary artery disease, dementia, depression, diabetes, hepatitis, human immunodeficiency virus (HIV), hyperlipidemia, hypertension, osteoporosis, post-traumatic stress disorder (PTSD), schizophrenia, substance use disorder, and stroke. KEY RESULTS: Multimorbidity is common among middle-aged and older patients seen in CHCs: 40% have somatic, 6% have mental health, and 24% have mental-somatic multimorbidity patterns. The most frequently occurring pattern across all years is hyperlipidemia-hypertension. The three most frequent patterns are various iterations of hyperlipidemia, hypertension, and diabetes and are consistent in rank of occurrence across all years. CKD-hyperlipidemia-hypertension and anxiety-depression are both more frequent in later study years. CONCLUSIONS: CHCs are increasingly seeing more complex multimorbidity patterns over time; these most often involve mental health morbidity and advanced cardiometabolic-renal morbidity.


Asunto(s)
Diabetes Mellitus , Hiperlipidemias , Hipertensión , Insuficiencia Renal Crónica , Persona de Mediana Edad , Humanos , Anciano , Multimorbilidad , Comorbilidad , Estudios de Cohortes , Diabetes Mellitus/epidemiología , Enfermedad Crónica , Hipertensión/epidemiología , Hiperlipidemias/epidemiología , Centros Comunitarios de Salud , Insuficiencia Renal Crónica/epidemiología , Prevalencia
3.
BMC Health Serv Res ; 22(1): 488, 2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35414079

RESUMEN

BACKGROUND: Smoking among cancer survivors can increase the risk of cancer reoccurrence, reduce treatment effectiveness and decrease quality of life. Cancer survivors without health insurance have higher rates of smoking and decreased probability of quitting smoking than cancer survivors with health insurance. This study examines the associations of the Affordable Care Act (ACA) Medicaid insurance expansion with smoking cessation assistance and quitting smoking among cancer survivors seen in community health centers (CHCs). METHODS: Using electronic health record data from 337 primary care community health centers in 12 states that expanded Medicaid eligibility and 273 CHCs in 8 states that did not expand, we identified adult cancer survivors with a smoking status indicating current smoking within 6 months prior to ACA expansion in 2014 and ≥ 1 visit with smoking status assessed within 24-months post-expansion. Using an observational cohort propensity score weighted approach and logistic generalized estimating equation regression, we compared odds of quitting smoking, having a cessation medication ordered, and having ≥6 visits within the post-expansion period among cancer survivors in Medicaid expansion versus non-expansion states. RESULTS: Cancer survivors in expansion states had higher odds of having a smoking cessation medication order (adjusted odds ratio [aOR] = 2.54, 95%CI = 1.61-4.03) and higher odds of having ≥6 office visits than those in non-expansion states (aOR = 1.82, 95%CI = 1.22-2.73). Odds of quitting smoking did not differ significantly between patients in Medicaid expansion versus non-expansion states. CONCLUSIONS: The increased odds of having a smoking cessation medication order among cancer survivors seen in Medicaid expansion states compared with those seen in non-expansion states provides evidence of the importance of health insurance coverage in accessing evidence-based tobacco treatment within CHCs. Continued research is needed to understand why, despite increased odds of having a cessation medication prescribed, odds of quitting smoking were not significantly higher among cancer survivors in Medicaid expansion states compared to non-expansion states.


Asunto(s)
Supervivientes de Cáncer , Neoplasias , Cese del Hábito de Fumar , Adulto , Estudios de Cohortes , Accesibilidad a los Servicios de Salud , Humanos , Cobertura del Seguro , Medicaid , Neoplasias/epidemiología , Neoplasias/terapia , Patient Protection and Affordable Care Act , Calidad de Vida , Estados Unidos/epidemiología
4.
Neurogenetics ; 16(1): 65-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25418441

RESUMEN

Mutations in STXBP1 have recently been identified as a cause of infantile epileptic encephalopathy. The underlying mechanism of the disorder remains unclear and, recently, several case reports have described broad and progressive neurological phenotypes in addition to early-onset epilepsy. Herein, we describe a patient with early-onset epilepsy who subsequently developed a progressive neurological phenotype including parkinsonism in her early teens. A de novo mutation in STXBP1 (c.416C>T, p.(Pro139Leu)) was detected with exome sequencing together with profound impairment of complex I of the mitochondrial respiratory chain on muscle biopsy. These findings implicate a secondary impairment of mitochondrial function in the progressive nature of the disease phenotype.


Asunto(s)
Complejo I de Transporte de Electrón/deficiencia , Epilepsia/genética , Enfermedades Mitocondriales/genética , Proteínas Munc18/genética , Mutación Missense , Trastornos Parkinsonianos/genética , Encéfalo/fisiopatología , Niño , Progresión de la Enfermedad , Electroencefalografía , Complejo I de Transporte de Electrón/genética , Epilepsia/complicaciones , Exoma , Femenino , Humanos , Enfermedades Mitocondriales/complicaciones , Trastornos Parkinsonianos/complicaciones , Fenotipo
5.
J Laryngol Otol ; 136(8): 775-782, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34641994

RESUMEN

BACKGROUND: Sudden hearing loss, or progressive hearing loss occurring over months to years, are well-established presentations. However, little is described in the medical literature on how to approach patients presenting with a rapidly progressive hearing loss occurring over weeks. This study aimed to evaluate the clinical significance of patients presenting with rapidly progressive hearing loss. METHODS: A case of rapidly progressive hearing loss occurring over 12 weeks is presented. A PubMed literature review was performed to determine the evidence-based differential diagnoses for rapidly progressive hearing loss. RESULTS: Fifteen causes were identified for rapidly progressive hearing loss: intracranial aetiologies (meningioma, lymphoma, metastatic deposit, cavernous angioma, meningitis, superficial siderosis); paraneoplastic syndrome (small cell lung carcinoma, thymoma); inflammatory or autoimmune disorders (autoimmune inner-ear disease, sarcoidosis, vasculitis, Sjögren's syndrome); infective disorders (syphilis, human immunodeficiency virus); and medication-induced causes. CONCLUSION: Rapidly progressive hearing loss should be considered a 'red flag' symptom that warrants urgent action. Most causes are systemic or sinister in nature, and the patient's hearing loss can potentially be reversed.


Asunto(s)
Enfermedades Autoinmunes , Sordera , Pérdida Auditiva Sensorineural , Pérdida Auditiva Súbita , Sordera/complicaciones , Diagnóstico Diferencial , Pérdida Auditiva Sensorineural/diagnóstico , Pérdida Auditiva Súbita/complicaciones , Pérdida Auditiva Súbita/etiología , Humanos
6.
Sci Rep ; 10(1): 6255, 2020 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-32277124

RESUMEN

In artificial insemination the use of sex-sorted bovine sperm results in reduced conception, the causes of which are only partly understood. Therefore, we set out to investigate the effects of sexing on bovine sperm function and early embryonic development. Computer-assisted semen analysis (CASA) of sperm of the same bulls (n = 5), before and after sexing, demonstrated significantly reduced fast (A) and slow (B) progressively motile sperm (p < 0.05) after sexing. Sexed-sperm also revealed significantly less hyperactivated sperm (p < 0.05). As shown by time-lapse videomicroscopy of in vitro produced embryos (n = 360), embryos derived from sexed-sperm displayed significantly increased incidences of arrest at the 4-cell stage (p < 0.05). The relative risk for shrinkage/fusion of blastomeres with subsequent lysis was 1.71 times higher in the embryos derived from sexed-sperm as compared to conventional embryos (p < 0.05) resulting in significantly reduced blastocyst rates (p < 0.001). The relative risk for cleavage was 2.36 times lower in the embryos derived from sex-sorted sperm (p < 0.001). Additionally, sexed-sperm-derived embryos showed reduced survival times (hazard ratio HR = 1.54, p < 0.001) which were bull dependent (p < 0.001). However, the percentage of apoptotic cells was similar to conventional embryos. Furthermore, embryos derived from sexed-sperm were found to reach developmental stages at similar timings as conventional embryos. Our results suggest that reduced conception rates after sexing are due to altered sperm morphokinetics, decreasing the chance of sperm to reach and fertilise the oocyte, and aberrant early embryonic development.


Asunto(s)
Desarrollo Embrionario/fisiología , Fertilización In Vitro/veterinaria , Espermatozoides/crecimiento & desarrollo , Animales , Bovinos , Separación Celular/métodos , Criopreservación , Embrión de Mamíferos/diagnóstico por imagen , Femenino , Fertilización In Vitro/métodos , Citometría de Flujo/métodos , Técnicas de Maduración In Vitro de los Oocitos/métodos , Masculino , Microscopía por Video , Oocitos/crecimiento & desarrollo , Embarazo , Análisis de Semen , Espermatozoides/patología , Imagen de Lapso de Tiempo
7.
Science ; 214(4518): 328-31, 1981 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-17829788

RESUMEN

Results of the first year of data collection by the SAM (Stratospheric Aerosol Measurement) II satellite system are presented. Almost 10,000 profiles of stratospheric aerosol extinction in the Arctic and Antarctic regions are used to construct plots of weekly averaged aerosol extinction versus altitude and time and stratospheric optical depth versus time. Corresponding temperature fields are presented. These data show striking similarities in the aerosol behavior for corresponding seasons. Wintertime polar stratospheric clouds that are strongly correlated with temperature are documented. They are much more prevalent in the Antarctic stratosphere during the cold austral winter and increase the stratospheric optical depths by as much as an order of magnitude for a period of about 2 months. These clouds might represent a sink for stratospheric water vapor and must be considered in the radiative budget for this region and time.

8.
J Biotechnol ; 130(4): 370-7, 2007 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-17601620

RESUMEN

We report on the isolation and biochemical characterization of a novel, cold-active and metagenome-derived lipase with a high stereo-selectivity for pharmaceutically important substrates. The respective gene was isolated from a cosmid library derived from oil contaminated soil and designated lipCE. The deduced aa sequence indicates that the protein belongs to the lipase family l.3, with high similarity to Pseudomonas fluorescens lipases containing a C-terminal secretion signal for ABC dependent transport together with possible motifs for Ca(2+)-binding sites. The overexpressed protein revealed a molecular weight of 53.2kDa and was purified by refolding from inclusion bodies after expression in Escherichia coli. The optimum temperature of LipCE was determined to be 30 degrees C. However, the enzyme still displayed 28% residual activity at 0 degrees C and 16% at -5 degrees C. Calcium ions strongly increased activity and thermal stability of the protein. Further detailed biochemical characterization of the recombinant enzyme showed an optimum pH of 7 and that it retained activity in the presence of a range of metal ions and solvents. A detailed analysis of the enzyme's substrate spectrum with more than 34 different substrates indicated that the enzyme was able to hydrolyze a wide variety of substrates including the conversion of long chain fatty acid substrates with maximum activity for pNP-caprate (C(10)). Furthermore LipCE was able to hydrolyze stereo-selectively ibuprofen-pNP ester with a high preference for the (R) enantiomer of >91% ee and it demonstrated selectivity for esters of primary alcohols, whereas esters of secondary or tertiary alcohols were nearly not converted.


Asunto(s)
Ibuprofeno/química , Lipasa/química , Lipasa/aislamiento & purificación , Proteobacteria/enzimología , Proteobacteria/genética , Mapeo Cromosómico/métodos , Frío , Activación Enzimática , Estabilidad de Enzimas , Estereoisomerismo , Especificidad por Sustrato
9.
J Biotechnol ; 126(1): 26-36, 2006 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-16584799

RESUMEN

Metagenomes of uncultured microorganisms represent a sheer unlimited resource for discovery of novel biocatalysts. Here, we report on the biochemical characterisation of a novel, soil metagenome-derived cellulase (endoglucanase), Cel5A. The deduced amino acid sequence of Cel5A was similar to a family 5, single domain cellulase with no distinct cellulose binding domain from Cellvibrio mixtus. The 1092bp ORF encoding Cel5A was overexpressed in Escherichia coli and the corresponding 42.1 kDa protein purified using three-step chromatography. The recombinant Cel5A protein was highly active against soluble cellulose substrates containing beta-1,4 linkages, such as lichenan and barley beta-glucan, and not active against insoluble cellulose. Glucose was not among the initial hydrolysis products, indicating an endo mode of action. Cel5A displayed a wide range of pH activity with a maximum at pH 6.5 and at least 60% activity at pH 5.5 and 9.0. The enzyme was highly stable at 40 degrees C for up to 11 days, and retained 86-87% activity after incubation with 3M NaCl, 3M RbCl or 4M KCl for 20 h. Cel5A was also active in the presence of diverse divalent cations, detergents and EDTA. This highly stable, salt and pH tolerant cellulase is an ideal candidate for industrial applications.


Asunto(s)
Celulasa/genética , Genoma , Cloruro de Sodio/farmacología , Especificidad por Sustrato/genética , Celulasa/química , Celulasa/aislamiento & purificación , Escherichia coli , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Microbiología del Suelo
10.
Nanoscale ; 8(46): 19219-19223, 2016 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-27845799

RESUMEN

Formation and quality of single solid supported lipid membranes and double lipid membranes were investigated with single vesicle resolution using label-free evanescence light scattering microscopy (EvSM). For the formation of double lipid membranes we made use of electrostatic interaction between charged lipids and oppositely charged cations.

11.
J Neurol ; 262(8): 1822-7, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25976027

RESUMEN

Sporadic late onset cerebellar ataxia is a well-described clinical presentation with a broad differential diagnosis that adult neurologists should be familiar with. However, despite extensive clinical investigations, an acquired cause is identified in only a minority of cases. Thereafter, an underlying genetic basis is often considered, even in those without a family history. Here we apply whole exome sequencing to a cohort of 12 patients with late onset cerebellar ataxia. We show that 33% of 'idiopathic' cases harbor compound heterozygous mutations in known ataxia genes, including genes not included on multi-gene panels, or primarily associated with an ataxic presentation.


Asunto(s)
Exoma/genética , Genes Recesivos/genética , Degeneraciones Espinocerebelosas/genética , Adulto , Anciano , Estudios de Cohortes , Inglaterra , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación/genética , Tasa de Mutación , Análisis de Secuencia de ADN
13.
J Consult Clin Psychol ; 64(1): 22-31, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8907081

RESUMEN

The relation of patterns of attachment and psychiatric status was studied in 82 nonpsychotic inpatients and 85 case-matched controls using the Adult Attachment Interview (AAI). AAI transcripts rated (masked to case vs. control status and treatment) were classified using M. Main and R. Goldwyn's (1991) system. Psychiatric patients, diagnosed with the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.) I and II structured interviews, were more likely to be classified as preoccupied and unresolved with respect to loss or abuse. On Axis I, anxiety was associated with unresolved status, and AAI scales were able to discriminate depression and eating disorder. On Axis II, borderline personality disorder (BPD) was linked to experience of severe trauma and lack of resolution with respect to it. BPD patients were also rated significantly lower on a scale measuring awareness of mental states. Preliminary outcome results suggest that individuals rated as dismissing on the AAI are more likely to show improvements in psychotherapy.


Asunto(s)
Trastornos Mentales/clasificación , Apego a Objetos , Psicoterapia , Trastorno de Personalidad Limítrofe/clasificación , Trastorno de Personalidad Limítrofe/psicología , Trastorno de Personalidad Limítrofe/terapia , Femenino , Humanos , Masculino , Trastornos Mentales/psicología , Trastornos Mentales/terapia , Persona de Mediana Edad , Admisión del Paciente , Determinación de la Personalidad , Resultado del Tratamiento
14.
Reprod Toxicol ; 1(4): 263-6, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-2980391

RESUMEN

Clomiphene citrate, administered to the neonatal mouse during cervicovaginal epithelial differentiation, is associated with subsequent adenosis. Similar lack of neonatal transformation of columnar to squamous epithelium occurs after diethylstilbestrol. Mouse neonatally exposed to diethylstilbestrol have a high incidence of reproductive tract tumors in later life. In this study Balb/c neonates were exposed to clomiphene citrate, maintained with controls, and killed at 52, 56, and 60 weeks. Cervicovaginal histology was studied by light microscopy. In all control animals only mature squamous epithelium was seen (44/44). After clomiphene citrate, at 52 weeks, 3/10 animals had other than mature squamous epithelium identified. One of these genital tracts contained adenosis. At 56 weeks only mature squamous epithelium was seen (11/11), and at 60 weeks immature squamous epithelium was identified in 1 of 10 animals. In no study animal (0/31) was there any evidence of tumor development. This differs from the high incidence of reproductive tract tumor seen in the mouse after neonatal diethylstilbestrol exposure.


Asunto(s)
Clomifeno/efectos adversos , Enfermedades del Sistema Endocrino/inducido químicamente , Neoplasias del Cuello Uterino/inducido químicamente , Vagina/efectos de los fármacos , Neoplasias Vaginales/inducido químicamente , Animales , Animales Recién Nacidos , Diferenciación Celular/efectos de los fármacos , Células Epiteliales , Epitelio/efectos de los fármacos , Femenino , Estudios Longitudinales , Ratones , Ratones Endogámicos BALB C , Vagina/citología
15.
Br J Psychol ; 84 ( Pt 4): 443-79, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8298858

RESUMEN

This paper attempts a critical review not so much of the concept of locus of control as the plethora of unidimensional or sphere-specific measures that have been developed in the past 25 years. After a brief history of the development of the concept of locus of control, various oft-repeated and some new criticisms are considered. One frequent response to problems associated with the original concept and scale has been to develop new psychometrically validated, sphere- or topic-specific measures. These are tabulated and reviewed under five headings: measures (either multidimensional or sphere-specific) of the general concept of locus of control; measures devised specifically for children and adolescents; measures that have concentrated on aspects of mental and physical health; work, career and economic locus of control measures; and finally, measures which have extended the locus of control concept into other areas. The advantages and disadvantages of this proliferation of measures is considered in some detail, especially the issue of incremental validity, and recommendations are made for future work in this area.


Asunto(s)
Empleo , Estado de Salud , Control Interno-Externo , Salud Mental , Femenino , Humanos , Masculino , Encuestas y Cuestionarios
16.
Can Vet J ; 42(4): 300-2, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11326636

RESUMEN

A 9-year-old, female guinea pig was diagnosed with a subcutaneous fibrosarcoma overlying the ventral thorax. The mass was invasive within the subcutis without extension into surrounding structures or organ systems. Other findings included cystic ovaries, renal cortical cysts, nodular hyperplasia of the liver, and myocardial fibrosis with pulmonary hypertension.


Asunto(s)
Fibrosarcoma/veterinaria , Cobayas , Recurrencia Local de Neoplasia/veterinaria , Enfermedades de los Roedores/patología , Neoplasias Cutáneas/veterinaria , Animales , Eutanasia/veterinaria , Resultado Fatal , Femenino , Fibrosarcoma/patología , Fibrosarcoma/cirugía , Recurrencia Local de Neoplasia/patología , Enfermedades de los Roedores/cirugía , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía
17.
J Am Psychoanal Assoc ; 41(4): 957-89, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8282943

RESUMEN

This paper presents a summary of the Anna Freud Centre-University College London, Parent-Child Project. Its most important finding was that the security of the infants' relationship with both parents at 12 and 18 months could be predicted on the basis of qualitative aspects of the parents' accounts of their own childhoods collected before the birth of the child. This confirmed Selma Fraiberg's observations concerning the reemergence of childhood conflicts at early stages of childbearing. Possible mechanisms mediating this link are explored with particular reference to the role of the parents' accurate mental representations of the infants' mental world.


Asunto(s)
Concienciación , Formación de Concepto , Apego a Objetos , Relaciones Padres-Hijo , Desarrollo de la Personalidad , Adulto , Ansiedad de Separación/psicología , Mecanismos de Defensa , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Determinación de la Personalidad , Embarazo , Teoría Psicoanalítica
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