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1.
J Pak Med Assoc ; 74(4): 719-723, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38751268

RESUMEN

Objective: To compare the procrastination and self-efficacy scores among students with respect to the academic year of dental undergraduate programme, and to assess the relationship between self-efficacy and academic procrastination among the students. METHODS: The descriptive study was conducted at Sindh Institute of Oral Health Sciences, Jinnah Sindh Medical University, Karachi, from January to March 2023, and comprised medical students of either gender from all the 4 academic years. Data was collected using a structured questionnaire whose validity was assessed using a pilot study. Data was analysed using SPSS 18. RESULTS: Of the 136 students, 84(61.8%) were females and 52(38.2%) were males. There were 34(25%) students from the 1st year, 32(23.5%) from 2nd year, 38(28%) from the 3rd year, and 32(23.5%) from the final year. The highest mean score for procrastination was from 3rd year students 67.7±12.8, while the highest mean score for self-efficacy was from 1st year students 30.2±4. There was no significant difference in terms of gender (p>0.05). Procrastination scores had a significant association with the academic year (p=0.016). Conclusion: Procrastination scores were high among the dental students with the highest score from 3rd year students. The academic environment should provide support help the students devise strategies to optimally utilise the available time.


Asunto(s)
Procrastinación , Autoeficacia , Estudiantes de Odontología , Humanos , Femenino , Masculino , Pakistán , Estudiantes de Odontología/psicología , Estudiantes de Odontología/estadística & datos numéricos , Adulto Joven , Encuestas y Cuestionarios , Educación en Odontología/métodos , Adulto
2.
bioRxiv ; 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37398253

RESUMEN

The dorsolateral prefrontal cortex (dlPFC) is an evolutionarily derived cortical region in primates critical for high-level cognitive functions and implicated in various neuropsychiatric disorders. The cells that compose the dlPFC, especially excitatory and inhibitory neurons, undergo extensive maturation throughout midfetal and late-fetal development, during which critical neurodevelopmental events, such as circuit assembly and electrophysiological maturation of neurons, occur. Despite the relevance of neuronal maturation in several neurodevelopmental and psychiatric disorders, the molecular mechanisms underlying this process remain largely unknown. Here, we performed an integrated Patch-seq and single-nucleus multiomic analysis of the rhesus macaque dlPFC to identify genes governing neuronal maturation from midfetal to late-fetal development. Our multimodal analysis identified gene pathways and regulatory networks important for the maturation of distinct neuronal populations, including upper-layer intratelencephalicprojecting neurons. We identified genes underlying the maturation of specific electrophysiological properties of these neurons. Furthermore, gene knockdown in organotypic slices revealed that RAPGEF4 regulates the maturation of resting membrane potential and inward sodium current. Using this strategy, we also found that the knockdown of CHD8, a high-confidence autism spectrum disorder risk gene, in human slices led to deficits in neuronal maturation, via the downstream downregulation of several key genes, including RAPGEF4. Our study revealed novel regulators of neuronal maturation during a critical period of prefrontal development in primates and implicated such regulators in molecular processes underlying autism.

3.
Hippocampus ; 33(4): 373-390, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36892196

RESUMEN

Adult hippocampal neurogenesis is important for preserving learning and memory-related cognitive functions. Physical exercise, especially voluntary running, is one of the strongest stimuli to promote neurogenesis and has beneficial effects on cognitive functions. Voluntary running promotes exit of neural stem cells (NSCs) from the quiescent stage, proliferation of NSCs and progenitors, survival of newborn cells, morphological development of immature neuron, and integration of new neurons into the hippocampal circuitry. However, the detailed mechanisms driving these changes remain unclear. In this review, we will summarize current knowledge with respect to molecular mechanisms underlying voluntary running-induced neurogenesis, highlighting recent genome-wide gene expression analyses. In addition, we will discuss new approaches and future directions for dissecting the complex cellular mechanisms driving change in adult-born new neurons in response to physical exercise.


Asunto(s)
Células-Madre Neurales , Condicionamiento Físico Animal , Carrera , Animales , Ratones , Proliferación Celular , Hipocampo/fisiología , Ratones Endogámicos C57BL , Células-Madre Neurales/fisiología , Neurogénesis/fisiología , Condicionamiento Físico Animal/fisiología , Carrera/fisiología
4.
Cureus ; 14(4): e24431, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35637806

RESUMEN

The new coronavirus quickly spread throughout the world in late 2019 and became a pandemic in early 2020. The most common symptoms observed are fever, dry cough, loss of taste and smell, and respiratory distress. Other rarer complications can involve the cardiovascular, gastrointestinal, or neurological systems. Of the neurological complications, epileptic seizures are a subject of particular interest due to their relatively unknown and widespread etiologies. It is understood that the entry or production of pro-inflammatory cytokines during a COVID-19 infection can result in neurotransmitter modulation and ion channel dysfunction, leading to neuronal hyperexcitability, presenting as seizures. To the best of our knowledge, we present the first case in sub-Saharan Africa of a COVID-19 positive patient presenting to our institution with a reported seizure followed by confusion. Our case highlights the need to broaden our differential diagnosis to include COVID-19 infections in patients presenting with seizures.

5.
J Ayub Med Coll Abbottabad ; 28(4): 762-765, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28586602

RESUMEN

BACKGROUND: Bronchial asthma is a common disease and most asthmatics are obese. Both asthma and obesity are showing parallel trends in their increasing prevalence. Obesity is also the main component of metabolic syndrome and several studies have shown metabolic syndrome to be associated with bronchial asthma. The present study was, therefore, designed to determine the frequency of metabolic syndrome among patients with chronic asthma in our setup. METHODS: This cross-sectional study was conducted in Department of Medicine, Ayub Teaching Hospital, Abbottabad from May to November, 2014. One hundred and fifty-four asthmatic patients were enrolled in this study. Samples for blood glucose, triglycerides and HDL Cholesterol were taken after an overnight fast. Sitting blood pressure was measured with mercury sphygmomanometer after 10 minutes of rest. Waist circumference was measured at the level of the midpoint between the high point of the iliac crest and the last rib. RESULTS: Out of 154 patients, 80 were males and 74 were females. Metabolic syndrome was diagnosed in 46 (29.87%) patients. When metabolic syndrome was stratified according to age, sex and duration of asthma, the results were found to be insignificant (p-0.89, 0.30 and 0.85). CONCLUSIONS: This study showed that metabolic syndrome was present in almost one third of study population.


Asunto(s)
Asma/epidemiología , Síndrome Metabólico/epidemiología , Adulto , Colesterol/sangre , Estudios Transversales , Femenino , Humanos , Masculino , Síndrome Metabólico/diagnóstico , Persona de Mediana Edad , Pakistán/epidemiología , Triglicéridos/sangre , Circunferencia de la Cintura
6.
J Hazard Mater ; 141(1): 37-44, 2007 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-16890349

RESUMEN

Sorption of traces of Cd(II) ions onto beach sand is investigated as a function of nature and concentration of electrolyte (10(-4) to 10(-2)M nitric, hydrochloric and perchloric acids, pH 2-10 buffers and deionized water), shaking time 5-40min, shaking speed 50-200strokes/min, dosage of sand (50-1000mg/15cm(3)), concentration of sorbate (1.04x10(-6) to 1.9x10(-4)M) and temperature (293-323K). Maximum sorption of Cd(II) ions (approximately 66%) is achieved from deionized water using 300mg/15cm(3) sand in 20min. The data are successfully tested by Langmuir, Freundlich and Dubinin-Redushkevich (D-R) sorption isotherms. The values for characteristic Langmuir constants Q=13.31+/-0.20micromol/g and of b=(6.56+/-0.53)x10(3)dm(3)/mol, Freundlich constants A=2.23+/-1.16mmol/g and 1/n=0.70+/-0.05 of (D-R) constants beta=-0.005068+/-0.000328kJ(2)/mol(2), X(m)=46.91+/-11.91micromol/g and energy E=9.92+/-0.32kJ/mol have been estimated. Kinetics of sorption has been studied by applying Morris-Weber, Richenberg and Lagergren equations. The sorption follows first order rate equation resulting 0.182+/-0.004min(-1) The thermodynamic parameters DeltaH=32.09+/-2.92kJ/mol, DeltaS=111.0+/-9.5J/molK and DeltaG=-1.68+/-0.02kJ/mol are evaluated. The influence of common ions on the sorption of Cd(II) ions is also examined. Some common ions reduce the sorption while most of the ions have very little effect. It can be concluded that beach sand may be used as an alternative for the expensive synthetic sorbents.


Asunto(s)
Cadmio/química , Dióxido de Silicio/química , Contaminantes Químicos del Agua/química , Adsorción , Aniones/química , Cationes Bivalentes/química , Cinética , Pakistán , Temperatura , Termodinámica , Eliminación de Residuos Líquidos/métodos
7.
Chemosphere ; 66(10): 1829-38, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17109916

RESUMEN

Sorptive potential of selected agricultural waste materials i.e. rice (Oryza sativa) bran (RB), bagasse fly ash (BFA) of sugarcane (Saccharum officinarum), Moringa oleifera pods (MOP) and rice husk (RH) for the removal of methyl parathion pesticide (MP) from surface and ground waters has been investigated. Optimization of operating parameters of sorption process, i.e. sorbent dose, agitation time, pH, initial concentration of sorbate, and temperature have been studied. The sorption data fitted to Freundlich, Langmuir and Dubinin-Radushkevich (D-R) sorption isotherms. The maximum capacities of RB, BFA, MOP and RH for MP were calculated to be 3.6+/-0.8, 5.3+/-1.4, 5.2+/-1.5 and 4.7+/-1.0 mmolg(-1) by Freundlich, 0.39+/-0.009, 0.39+/-0.005, 0.36+/-0.004 and 0.35+/-0.008 mmolg(-1) by Langmuir and 0.9+/-0.08, 1.0+/-0.10, 1.0+/-0.10 and 0.9+/-0.07 mmolg(-1) by D-R isotherms respectively, employing 0.1g of each sorbent, at pH 6, 90 min agitation time and at 303 K. Application of first order Lagergren and Morris-Weber equations to the kinetic data yielded correlation coefficients, close to unity. Thermodynamic parameters of sorption process, i.e. DeltaH, DeltaS and DeltaG were computed and their negative values indicated the exothermic and spontaneous nature of sorption process. The pesticide may be stripped by sonication with methanol, making the regeneration and reutilization of sorbents promising. The sorbents investigated exhibited their potential applications in water decontamination, treatment of industrial and agricultural waste waters.


Asunto(s)
Residuos Industriales , Metil Paratión/química , Plaguicidas/química , Adsorción , Restauración y Remediación Ambiental/métodos , Concentración de Iones de Hidrógeno , Metil Paratión/aislamiento & purificación , Estructura Molecular , Plaguicidas/aislamiento & purificación , Termodinámica , Factores de Tiempo , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos
8.
J Environ Manage ; 81(3): 286-95, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16713064

RESUMEN

Coconut (Cocos nucifera) husk, an agricultural waste, has been thoroughly investigated for the removal of toxic Cd(II), Cr(III) and Hg(II) ions from aqueous media. The parameters like nature and composition of electrolyte, concentration of toxic ions, dosage of coconut husk, and equilibration time between the two phases were optimized for their maximum accumulation onto the solid surface. The effect of common ions on the uptake of metal ions has been monitored under optimal conditions. The variation of retention of each metal ion with temperature was used to compute the thermodynamic quantities DeltaH, DeltaS and DeltaG. The values 18.1+/-0.6 kJmol(-1), 74+/-2 Jmol(-1)K(-1), and -3.8+/-0.04 kJmol(-1) at 298 K; 10.8+/-0.8 kJmol(-1), 48.8+/-2.7 Jmol(-1)K(-1), and -4.6+/-0.3 kJmol(-1) at 298 K; and -37.4+/-2k Jmol(-1), 105+/-7 Jmol(-1)K(-1) and -2.58+/-0.5 kJmol(-1) at 298 K were obtained for Cd(II), Cr(III) and Hg(II) ions, respectively. The sorption data were analysed by applying different sorption isotherms. The sorption capacity and energy were evaluated for each metal ion. The values of the Freundlich constants 1/n and C(m) were 0.92+/-0.04 and 52.6+/-22.2 mmolg(-1); 0.85+/-0.05 and 56.0+/-0.03 mmolg(-1); and 0.88+/-0.03 and 6.84+/-0.45 mmolg(-1) for Cd(II) Cr(III) and Hg(II) ions, respectively. Similarly, the Dubinin-Radushkevich (D-R) constants beta, X(m,) and E were evaluated for the three metal ions. To check the selectivity of the sorbent, sorption of a number of elements was measured under similar conditions. Separation of Zn(II) from Cd(II); Cr(III) from I(I), Zr(IV), Se(IV), and Hg(II) from Se(IV) and Zn(II) can be achieved using this sorbent. This cheap material has potential applications in analytical chemistry, water decontamination, industrial effluent treatment and in pollution abatement.


Asunto(s)
Cocos/química , Metales Pesados/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Adsorción , Cationes , Concentración de Iones de Hidrógeno , Cinética , Temperatura , Eliminación de Residuos Líquidos/economía , Purificación del Agua/economía
9.
Talanta ; 66(1): 166-73, 2005 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-18969977

RESUMEN

The sorptive potential of sunflower stem (180-300mum) for Cr(III) ions has been investigated in detail. The maximum sorption (>/=85%) of Cr(III) ions (70.2muM) has been accomplished using 30mg of high density sunflower stem in 10min from 0.001M nitric and 0.0001M hydrochloric acid solutions. The accumulation of Cr(III) ions on the sorbent follows Dubinin-Radushkevich (D-R), Freundlich and Langmuir isotherms. The isotherm yields D-R saturation capacity X(m)=1.60+/-0.23mmolg(-1), beta=-0.00654+/-0.00017kJ(2)mol(-2), mean free energy E=8.74+/-0.12kJmol(-1), Freundlich sorption capacity K(F)=0.24+/-0.11molg(-1), 1/n=0.90+/-0.04 and of Langmuir constant K(L)=6800+/-600dm(3)mol(-1) and C(m)=120+/-18micromolg(-1). The variation of sorption with temperature (283-323K) gives DeltaH=-23.3+/-0.8kJmol(-1), DeltaS=-64.0+/-2.7Jmol(-1)K(-1) and DeltaG(298k)=-4.04+/-0.09kJmol(-1). The negative enthalpy and free energy envisage exothermic and spontaneous nature of sorption, respectively. Bisulphate, Fe(III), molybdate, citrate, Fe(II), Y(III) suppress the sorption significantly. The selectivity studies indicate that Cr(III), Eu(III) and Tb(III) ions can be separated from Tc(VII) and I(I). Sunflower stem can be used for the preconcentration and removal of Cr(III) ions from aqueous medium. This cheaper and novel sorbent has potential applications in analytical and environmental chemistry, in water decontamination, industrial waste treatment and in pollution abatement. A possible mechanism of biosorption of Cr(III) ions onto the sunflower stem has been proposed.

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