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1.
Int J Med Inform ; 158: 104653, 2021 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-34875485

RESUMEN

OBJECTIVE: To explore obstetrics patients' experiences with telemedicine during COVID-19 and assess their intent for its future use. DESIGN: An exploratory design was applied considering that telemedicine was a new phenomenon in Pakistan particularly for antenatal care services during COVID-19. METHOD: Primary data was collected through a telephonic survey of 132 respondents randomly selected from the pool of obstetrics patients who used telemedicine services of Shifa International Hospital (SIH) in Islamabad, Pakistan during the pandemic. We changed the survey tool of Medical Group Management Association to the study purpose. Required information included the respondents' socioeconomic and antenatal characteristics and their telemedicine use experience on four parameters, namely, Appointment, Staff Attitude, Communication, and Telemedicine Services. Patients were inquired about their intent to use telemedicine beyond COVID-19 and the reasons supporting their answer. The data was analyzed descriptively and through t-test mean comparisons and binary logistic regression. RESULTS: Majority (54%) intend to use telemedicine in future. Average age of respondents was 30 years with gravidity 2.36, parity 1.40 and gestational amenorrhea 27.3 weeks. The respondents average schooling was 9.5 years, marriage duration was 4.5 years and monthly household income was PKR ∼83,000. However, the overall experience of those who were confident in future use of telemedicine was 0.677 points higher and significantly different than those who were not inclined to use it in future. Of those lacking interest in future use of telemedicine, nearly two-third felt in-person visit was more satisfying, 11% needed physical examination, ∼6% experienced long waiting time, 5% each had inadequate access to ICT and online payment facilities, and 6% faced other issues such as excess payments. The binary logistic regression analysis (R2 37.3%) held Medical Consultations and Communications as the most important determinants and could predict nearly two-fifth of variation in respondents' intent for future use of telemedicine. CONCLUSION: Uptake of telemedicine for obstetrics patients is one of the positive externalities of COVID-19 and may appear as a cost-effective and culturally acceptable way to ensure universal coverage of antenatal care in Pakistan. However, telemedicine's future beyond COVID-19 for obstetrics hinges upon improving users' experience primarily through consultant and staff trainings and provision of effective communication e.g., in regional languages. Besides, offering physical examination facility and ability to use mobile wallet payment solutions may motivate future use of telemedicine in obstetrics.

2.
Stem Cells ; 39(7): 959-974, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33662144

RESUMEN

Retinal organoids (ROs) derived from human inducible pluripotent stem cells (hiPSCs) exhibit considerable therapeutic potential. However, current quality control of ROs during in vitro differentiation is largely limited to the detection of molecular markers, often by immunostaining, polymerase chain reaction (PCR) assays and sequencing, often without proper functional assessments. As such, in the current study, we systemically characterized the physiological maturation of photoreceptor-like cells in hiPSC-derived ROs. By performing patch-clamp recordings from photoreceptor-like cells in ROs at distinct differentiation stages (ie, Differentiation Day [D]90, D150, and D200), we determined the electrophysiological properties of the plasma membrane and several characteristic ion channels closely associated with the physiological functions of the photoreceptors. Ionic hallmarks, such as hyperpolarization-activated cyclic nucleotide-gated (HCN) channels and cyclic nucleotide-gated (CNG) channels, matured progressively during differentiation. After D200 in culture, these characteristic currents closely resembled those in macaque or human native photoreceptors. Furthermore, we demonstrated that the hyperpolarization-activated inward current/depolarization-activated outward current ratio (I-120 /I+40 ), termed as the inward-outward current (IOC) ratio hereon, accurately represented the maturity of photoreceptors and could serve as a sensitive indicator of pathological state. Thus, this study provides a comprehensive dataset describing the electrophysiological maturation of photoreceptor-like cells in hiPSC-derived ROs for precise and sensitive quality control during RO differentiation.


Asunto(s)
Células Madre Pluripotentes Inducidas , Células Madre Pluripotentes , Diferenciación Celular , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Organoides/metabolismo , Células Fotorreceptoras , Células Madre Pluripotentes/metabolismo , Retina/metabolismo
3.
Sci Adv ; 6(6): eaay5247, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32083182

RESUMEN

Retinal organoids (ROs) derived from human induced pluripotent stem cells (hiPSCs) provide potential opportunities for studying human retinal development and disorders; however, to what extent ROs recapitulate the epigenetic features of human retinal development is unknown. In this study, we systematically profiled chromatin accessibility and transcriptional dynamics over long-term human retinal and RO development. Our results showed that ROs recapitulated the human retinogenesis to a great extent, but divergent chromatin features were also discovered. We further reconstructed the transcriptional regulatory network governing human and RO retinogenesis in vivo. Notably, NFIB and THRA were identified as regulators in human retinal development. The chromatin modifications between developing human and mouse retina were also cross-analyzed. Notably, we revealed an enriched bivalent modification of H3K4me3 and H3K27me3 in human but not in murine retinogenesis, suggesting a more dedicated epigenetic regulation on human genome.


Asunto(s)
Ensamble y Desensamble de Cromatina , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Organogénesis , Organoides , Retina/citología , Retina/metabolismo , Animales , Biomarcadores , Diferenciación Celular/genética , Cromatina/genética , Epigénesis Genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Inmunohistoquímica , Ratones , Transducción de Señal
4.
Stem Cell Res ; 39: 101491, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31326746

RESUMEN

Retinal organoids (ROs) derived from human-induced pluripotent stem cells recapitulate the three-dimensional structure of retina, mimic human retinal development, and provide cell sources for pre-clinical retinal transplantation. Retinal pigment epithelium (RPE) is crucial for normal outer retinal physiology, including phagocytosis of shed photoreceptor outer segments and secretion of neurotrophic and vasculotrophic growth factors. However, whether ROs-RPE co-culture can improve the differentiation of photoreceptors in ROs in vitro remains unknown. Herein, primary mouse RPE cells were contact co-cultured with ROs at different time points. Our results revealed that the RPE cells accelerated photoreceptor differentiation in ROs, as the cross talk between the RPE and ROs promoted the stage specific expression of photoreceptor markers at different differentiation stages. Thus, we established an improved co-culture system based on modeling of human retina-RPE dynamics during retinogenesis for the evaluation of ocular therapies.


Asunto(s)
Técnicas de Cocultivo/métodos , Células Madre Pluripotentes Inducidas/citología , Organoides/citología , Epitelio Pigmentado de la Retina/citología , Animales , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Línea Celular , Medios de Cultivo Condicionados/farmacología , Humanos , Inmunohistoquímica , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Ratones , Organoides/efectos de los fármacos , Epitelio Pigmentado de la Retina/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
5.
Anim Sci J ; 89(12): 1692-1700, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30280470

RESUMEN

Absorption of ammonia from the rumen of cattle decreases nitrogen availability for fermentational protein synthesis, leading to increased competition of cattle with humans for protein and enhancing the release of toxic nitrogenous compounds into the environment. Given that differences in feeding and breeding might induce differences in ruminal ammonia transport, we compared electrophysiological, histological, and molecular biological characteristics of ruminal epithelia of Bos indicus crossbreds (Sahiwal-Mix, SWM) with those of Bos taurus (Holstein-Friesian, HF). As in HF, the stratified cornified epithelium of SWM expressed claudin 1 and 4. Measurements of ammonia flux (HF) and serosal pH (both breeds) suggested that at a mucosal pH of 6.4, net transport primarily occurred as NH4 + . As shown previously for HF, NH4 + induced a concentration-dependent rise in short circuit current (Isc ) in SWM that could be further stimulated by the TRP channel agonist menthol. Relative mRNA expression levels for TRPV3, TRPV4, TRPM6, and TRPM7 were significantly lower in SWM than in HF, with TRPA1 expression near the limit of detection. We conclude that uptake of ammonia from the rumen of both breeds occurs electrogenically as NH4 + with functional and molecular biological evidence pointing towards involvement of TRPV3 and TRPV4.


Asunto(s)
Amoníaco/metabolismo , Bovinos/genética , Bovinos/metabolismo , Hibridación Genética/genética , Hibridación Genética/fisiología , Rumen/metabolismo , Animales , Transporte Biológico/genética , Epitelio , Técnicas In Vitro , Absorción Intestinal/genética , Nitrógeno/metabolismo , Biosíntesis de Proteínas , Canales Catiónicos TRPV/fisiología
6.
Environ Pollut ; 242(Pt A): 126-135, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29966836

RESUMEN

Given that cadmium (Cd) uptake by plants is linked to transpiration rate and activity of antioxidant enzymes and further that silicon (Si) can regulate them, it was hypothesized that improved Si nutrition could reduce Cd concentration in plants. Thus, present study was carried out to elucidate the positive effect of Si nutrition on the growth, activities of antioxidant enzymes and tissue cadmium (Cd) concentration in Cd-tolerant (Iqbal-2000) and Cd-sensitive wheat (Triticum aestivum L.) cultivars. Fifteen days after seedling transplantation, 15 µM Cd stress alone and in combination with 0.6 mM Si was applied. Silicon application improved root and shoot dry matter of Cd-sensitive cultivar Sehar-2006 while the effect was non-significant in Cd-tolerant cultivar Iqbal-2000. Silicon-treated Cd-sensitive cultivar showed marked improvements in chlorophyll content and photosynthesis, while stomatal conductance and transpiration rate decreased by Si application. Silicon treatment enhanced the activities of enzymatic antioxidants including catalase, ascorbate peroxidase, guaiacol peroxidase and superoxide dismutase and the increase was higher for Cd-tolerant cultivar Iqbal-2000. Although Si nutrition depressed malondialdehyde (MDA) content in both Cd-stressed cultivars, the response was more evident in Cd-sensitive Sehar-2006. Lower lipid peroxidation was related to Si-induced increase in antioxidant activities only in Cd-sensitive cultivar. Silicon application decreased Cd accumulation in the roots and shoots of both the cultivars. The decrease in shoot Cd was associated with a decrease in Cd uptake by roots and Cd translocation from roots to shoots. Overall, it is concluded that Si suppressed Cd contents by decreasing transpiration rate in Cd-sensitive cultivar and by increasing antioxidant activity in Cd-tolerant cultivar.


Asunto(s)
Cadmio/metabolismo , Silicio/metabolismo , Triticum/enzimología , Antioxidantes/metabolismo , Ascorbato Peroxidasas , Cadmio/toxicidad , Catalasa/metabolismo , Clorofila/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Malondialdehído , Peroxidasa , Fotosíntesis/efectos de los fármacos , Plantones/metabolismo , Superóxido Dismutasa/metabolismo , Triticum/metabolismo
7.
Front Plant Sci ; 9: 263, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29593751

RESUMEN

Humic substances (HSs) have considerable effects on soil fertility and crop productivity owing to their unique physiochemical and biochemical properties, and play a vital role in establishing biotic and abiotic interactions within the plant rhizosphere. A comprehensive understanding of the mode of action and tissue distribution of HS is, however, required, as this knowledge could be useful for devising advanced rhizospheric management practices. These substances trigger various molecular processes in plant cells, and can strengthen the plant's tolerance to various kinds of abiotic stresses. HS manifest their effects in cells through genetic, post-transcriptional, and post-translational modifications of signaling entities that trigger different molecular, biochemical, and physiological processes. Understanding of such fundamental mechanisms will provide a better perspective for defining the cues and signaling crosstalk of HS that mediate various metabolic and hormonal networks operating in plant systems. Various regulatory activities and distribution strategies of HS have been discussed in this review.

8.
Front Genet ; 8: 141, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29089961

RESUMEN

Systems biology and omics has provided a comprehensive understanding about the dynamics of the genome, metabolome, transcriptome, and proteome under stress. In wheat, abiotic stresses trigger specific networks of pathways involved in redox and ionic homeostasis as well as osmotic balance. These networks are considerably more complicated than those in model plants, and therefore, counter models are proposed by unifying the approaches of omics and stress systems biology. Furthermore, crosstalk among these pathways is monitored by the regulation and streaming of transcripts and genes. In this review, we discuss systems biology and omics as a promising tool to study responses to oxidative, salinity, and drought stress in wheat.

9.
Environ Sci Pollut Res Int ; 24(6): 5521-5529, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28028706

RESUMEN

Cadmium (Cd) is a biologically non-essential heavy metal while the cultivation of Cd-tolerant varieties/hybrids (V) seems the most promising strategy for remediation of Cd-contaminated soils. For this, 24-day-old seedlings of seven maize hybrids, DKC 65-25, DKC 61-25, DKC 919, 23-T-16, 32-B-33, 31-P-41, and Syn hybrid, were grown in hydroponic conditions for 21 additional days in various Cd concentrations (0, 5, 10, and 15 µM). Effects of variety, Cd, and their interaction were highly significant (p ≤ 0.05) for studied plant agronomic and physiological traits except the V × Cd interaction for leaf chlorophyll content, root-shoot length, and root dry weight. The Cd accumulation in root and shoot increased gradually with increasing Cd treatments while copper (Cu), zinc (Zn), and manganese (Mn) uptake was decreased in all hybrids. The reduction in root and shoot biomass and Cd uptake was lower in 32-B-33 and 23-T-16 compared to other hybrids. The highest accumulation of Cu, Zn, and Mn was observed in 32-B-33, DK C65-25, and 31-P-41, respectively. The differential uptake and accumulation of Cd by maize hybrids may be useful in selection and breeding for Cd-tolerant genotypes.


Asunto(s)
Cadmio/toxicidad , Fotosíntesis , Contaminantes del Suelo/toxicidad , Zea mays , Biomasa , Clorofila/metabolismo , Cobre , Contaminación Ambiental , Hidroponía , Manganeso , Hojas de la Planta/metabolismo , Raíces de Plantas , Plantones , Zinc/análisis
10.
J Ayub Med Coll Abbottabad ; 21(3): 12-6, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20929003

RESUMEN

BACKGROUND: Ovulatory dysfunction is a group of disorders with variable clinical presentations occasionally having serious long-term adverse effects. It accounts for 30% of female fertility problems. Evidence suggests an association between an individual's weight and disorders of ovulation. The objective of our study was to describe the clinical and hormonal profile of subfertile women with ovulatory dysfunction in relation to their body mass index (BMI). METHODS: This prospective, descriptive study was carried out in Mother and Child Health Centre, PIMS, Islamabad and Railway hospital, Rawalpindi from April 2001 to March 2007. One hundred & thirty eight infertile patients with ovulatory dysfunction were included. The clinical data including BMI of each patient was recorded in addition to reports of investigations comprised of cervical smear, pelvic ultrasound and hormonal profile. RESULTS: Primary infertility was found in 61% while secondary in 39% of the patients. The mean age was 29 years and mean duration of infertility was 6 years. Menstrual pattern was normal in 56.5%. BMI was normal in 30.4% while most patients were overweight and obese. Prolonged cycles, history of systemic endocrine disorders, abnormal vaginal discharge, hirsutism, polycystic ovarian morphology and hormonal abnormalities were more frequent in patients with increased BMI. During the study period, 21.7% of the women conceived. CONCLUSION: Infertile patients with ovulatory dysfunction present more frequently with primary infertility. They usually have higher than required BMI. Oligomenorrhoea amenorrhoea, hirsutism and hormonal abnormalities are more frequent in overweight than infertile patients with ovulatory dysfunction having a normal BMI.


Asunto(s)
Anovulación/fisiopatología , Índice de Masa Corporal , Infertilidad Femenina/fisiopatología , Adulto , Anovulación/epidemiología , Femenino , Humanos , Infertilidad Femenina/epidemiología , Pakistán , Estudios Prospectivos , Factores de Riesgo
11.
J Coll Physicians Surg Pak ; 17(4): 199-202, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17462175

RESUMEN

OBJECTIVE: To determine the frequency of endometriosis in general gynecological and infertile women presenting to hospital and to correlate symptomatology and stage of disease. DESIGN: Cross-sectional study. PLACE AND DURATION OF STUDY: Gynecology Department of Mother and Child Health Center, Pakistan Institute of Medical Sciences, Islamabad, from March 2000 to March 2002. PATIENTS AND METHODS: Fifty patients with diagnosis of endometriosis on laparoscopy were included in the study. The degree of pain symptoms was graded according to 1-4 point verbal rating scale designed by Biberoglu and Behrman. Endometriosis was staged according to Revised American Fertility Society (R-AFS) scoring on laparoscopy. Correlation coefficient-Spearman rank order correlation test was applied to analyze data. RESULTS: The frequency of endometriosis in infertile women was 24% (33) and in women with general gynecological complaints, it was 23% (17). There was a significant positive correlation between chronic pelvic pain and R-AFS scoring. Increasing severity of pelvic pain was also positively correlated with presence of endometrioma and complete obliteration of pouch of Douglas. No correlation between dysmenorrhoea and R-AFS scoring could be detected. Dysmenorrhoea was strongly and positively correlated with the presence of superficial implants. Dyspareunia was found to have positive correlation with R-AFS score and also with complete obliteration of pouch of Douglas. CONCLUSION: The frequency of endometriosis in infertile women was 24% (33) and in women with general gynecological complaints, it was 23% (17). Chronic pelvic pain and dyspareunia had strong positive correlation with R-AFS score while dysmenorrhoea had no such correlation.

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