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1.
J Chem Phys ; 158(20)2023 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-37222296

RESUMEN

A low-frequency dielectric response of a ferrofluid based on transformer oil and MnZn ferrite nanoparticles is investigated in a gradient magnetic field. Four ferrofluid samples of various nanoparticle concentrations were introduced into planar micro-capacitors located over a magnetized tip. The dielectric spectra were measured in the frequency range from 0.1 Hz to 200 kHz and in the local magnetic field up to 100 mT. The spectra exhibit a dielectric relaxation ascribed to nanoparticle interfacial polarization. The low-frequency spectrum of each ferrofluid decreases upon application of the magnetic field up to 20 mT. The decrease in dielectric permittivity is caused by a magnetic force acting on larger nanoparticles in the gradient magnetic field. It is assumed that the interfaces of the concentrated nanoparticles in the gradient field do not contribute to the effective dielectric response. This reduces the effective relaxation time and shifts the relaxation toward higher frequencies. The dielectric spectra are well described by a relaxation fit function consisting of one Havriliak-Negami and a conductivity term. The fitting confirms that the only effect of the gradient magnetic field on the dielectric spectra is the shift of the dielectric relaxation and the decrease of the amplitude in the imaginary permittivity. This behavior is evident from a master plot, where all dielectric relaxations are superimposed on a single line. The knowledge of the presented behavior of the ferrofluid may be valuable when applying a ferrofluid to sharply magnetized parts of various electrical equipment (wires, tips, screws, nails, edges) as a liquid dielectric medium.

2.
Int J Occup Saf Ergon ; 28(3): 1711-1721, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34042562

RESUMEN

Objectives. The combined role of whole-body vibration (WBV) exposure and awkward posture on musculoskeletal disorders (MSDs) experienced by dumper operators in two metalliferous mines in India was evaluated through a cross-sectional study. Methods. Frequency-weighted root mean square (rms) acceleration was used for WBV exposure assessment. Anthropometry and rapid upper limb assessment (RULA) were used for static and dynamic posture assessment, respectively. Prevalence of MSDs was assessed using the Nordic musculoskeletal questionnaire (NMQ). Logistic regression was used to assess the factors contributing to MSD problems. Results. The rms values revealed that the operators exceeded the lower limit of Standard No. ISO 2631-1:1997. The dynamic posture study revealed that the majority of dumper operators were taking awkward postures and 58-74% of them were subjected to high and medium levels of MSD risk. The adjusted odds ratio (7.96, 95% confidence interval [1.24, 41.35]) for the most awkward postures revealed WBV exposure as the significant risk factor for MSD problems among the operators. Conclusion. WBV exposure and posture of operators should be regularly monitored and corrective actions implemented to reduce their MSD problems. Ergonomic seat design based on the anthropometry of the operators should be assessed at the time of procuring new equipment.


Asunto(s)
Enfermedades Musculoesqueléticas , Enfermedades Profesionales , Exposición Profesional , Estudios Transversales , Ergonomía , Humanos , Enfermedades Musculoesqueléticas/epidemiología , Enfermedades Musculoesqueléticas/etiología , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/etiología , Exposición Profesional/efectos adversos , Postura , Vibración/efectos adversos
3.
Cell Stress Chaperones ; 25(2): 327-344, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32062819

RESUMEN

The present study sought to evaluate mRNA expression profiles in the cultured dermal fibroblasts of Tharparkar (zebu) and Karan-Fries (zebu, Tharparkar × taurine, Holstein Friesian) cattle in response to heat stress. Bioinformatics' analysis identified temperature-regulated biological processes and pathways. Biological processes overrepresented among the earliest genes induced by temperature stress include regulation of stress responses, protein repair, metabolism, protein transport, cell division, and apoptosis. The present microarray platform contains 51,338 synthesized oligonucleotide probes corresponding to at least 36,713 unigenes. A total of 11,183 and 8126 transcripts were differentially expressed with a fold change of ≥ 2 in Tharparkar and Karan-Fries cattle, respectively. Randomly selected real-time validation showed 83.33% correlation with microarray data. Functional annotation and pathway study of the differentially expressed transcripts or genes (DEGs) reveal that upregulated genes significantly (P < 0.05) affect protein processing and NOD-like receptor pathways (NLRs), while downregulated genes were significantly (P < 0.05) found to be associated with cell cycle, metabolism, and protein transport. Gene expression changes include activation of heat shock factors (HSFs), increased expression of heat shock proteins (HSPs), and apoptosis, while decreasing protein synthesis and another metabolism. These findings provide insights into the underlying mechanism of the physiology of heat stress in Tharparkar and Karan-Fries cattle. Understanding the biology and mechanisms of heat stress is critical to developing approaches to ameliorate current production issues for improving animal performance and agriculture economics in tropical climatic conditions. In conclusion, the present study indicates that heat stress differentially affects the expression of the significant number of genes associated with stress response, metabolism, apoptosis, and protein transport in dermal fibroblasts of Tharparkar and Karan-Fries cattle.


Asunto(s)
Fibroblastos , Proteínas de Choque Térmico/metabolismo , Respuesta al Choque Térmico , Piel , Animales , Bovinos , Células Cultivadas , Femenino , Fibroblastos/citología , Fibroblastos/metabolismo , Expresión Génica , India , Piel/citología , Piel/metabolismo , Clima Tropical
4.
Heliyon ; 5(12): e02952, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31872123

RESUMEN

BACKGROUND: In response to various environmental stresses, many plant species synthesize L-proline in the cytosol and accumulates in the chloroplasts. L-Proline accumulation in plants is a well-recognized physiological reaction to osmotic stress prompted by salinity, drought and other abiotic stresses. L-Proline plays several protective functions such as osmoprotectant, stabilizing cellular structures, enzymes, and scavenging reactive oxygen species (ROS), and keeps up redox balance in adverse situations. In addition, ample-studied osmoprotective capacity, L-proline has been also ensnared in the regulation of plant improvement, including flowering, pollen, embryo, and leaf enlargement. SCOPE AND CONCLUSIONS: Albeit, ample is now well-known about L-proline metabolism, but certain characteristics of its biological roles are still indistinct. In the present review, we discuss the L-proline accumulation, metabolism, signaling, transport and regulation in the plants. We also discuss the effects of exogenous L-proline during different environmental conditions. L-Proline biosynthesis and catabolism are controlled by several cellular mechanisms, of which we identify only very fewer mechanisms. So, in the future, there is a requirement to identify such types of cellular mechanisms.

5.
Bot Stud ; 58(1): 44, 2017 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-29098503

RESUMEN

Plant defense against their pathogens can be induced by a complex network of different inducers. The present study investigates the synergistic effect of Trichoderma harzianum, exogenous salicylic acid (SA) and methyl jasmonate (MeJA) over the response and regulation of the antioxidant defense mechanisms and lipid peroxidation in tomato plants against Fusarium wilt disease. In the present work, tomato plants were infected by Fusarium oxysporum f. sp. lycopersici 3 days after inoculated with T. harzianum and/or sprayed daily for 3 days with chemical inducers (SA and MeJA). Plants were analysed at 0, 24, 48, 72 and 96 h after inoculation with Fusarium oxysporum f. sp. lycopersici. Infection of tomato plants by pathogen led to strong reduction in the dry weight of roots and shoots with the enhanced concentration of H2O2 and varying degree of lipid peroxidation. Concurrently, exogenous SA, when applied with pathogen greatly enhanced H2O2 content as well as activities of antioxidant enzymes except catalase (CAT) and ascorbate peroxidase (APx). The pathogen challenged plants pretreated with T. harzianum and MeJA together exhibited less lipid peroxidation and as well as the elevated level of ascorbic acid and enhanced activities of antioxidant enzymes. All applied treatments protected tomato seedlings against Fusarium wilt disease but the percentage of protection was found higher in plants pretreated with the combination of T. harzianum and chemical inducers.

6.
Sci Rep ; 7(1): 8777, 2017 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-28821789

RESUMEN

Alternaria species produce various sorts of toxic metabolites during their active growth and causes severe diseases in many plants by limiting their productivity. These toxic metabolites incorporate various mycotoxins comprising of dibenzo-α-pyrone and some tetramic acid derivatives. In this study, we have screened out total 48 isolates of Alternaria from different plants belonging to different locations in India, on the basis of their pathogenic nature. Pathogenicity testing of these 48 strains on susceptible tomato variety (CO-3) showed 27.08% of the strains were highly pathogenic, 35.41% moderately pathogenic and 37.5% were less pathogenic. Phylogenetic analysis showed the presence of at least eight evolutionary cluster of the pathogen. Toxins (TeA, AOH and AME) were isolated, purified on the basis of column chromatography and TLC, and further confirmed by the HPLC-UV chromatograms using standards. The final detection of toxins was done by the LC-MS/MS analysis by their mass/charge ratio. The present study develops an approach to classify the toxicogenic effect of each of the individual mycotoxins on tomato plant and focuses their differential susceptibility to develop disease symptoms. This study represents the report of the natural occurrence and distribution of Alternaria toxins in various plants from India.


Asunto(s)
Alternaria/metabolismo , Micotoxinas/aislamiento & purificación , Micotoxinas/farmacología , Alternaria/clasificación , Alternaria/genética , Muerte Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , ADN Espaciador Ribosómico , India , Micotoxinas/análisis , Filogenia , Células Vegetales/efectos de los fármacos , Sensibilidad y Especificidad , Espectrometría de Masas en Tándem , Toxicología/métodos
7.
Front Plant Sci ; 8: 161, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28265276

RESUMEN

Abiotic stress is one of the severe stresses of environment that lowers the growth and yield of any crop even on irrigated land throughout the world. A major phytohormone abscisic acid (ABA) plays an essential part in acting toward varied range of stresses like heavy metal stress, drought, thermal or heat stress, high level of salinity, low temperature, and radiation stress. Its role is also elaborated in various developmental processes including seed germination, seed dormancy, and closure of stomata. ABA acts by modifying the expression level of gene and subsequent analysis of cis- and trans-acting regulatory elements of responsive promoters. It also interacts with the signaling molecules of processes involved in stress response and development of seeds. On the whole, the stress to a plant can be susceptible or tolerant by taking into account the coordinated activities of various stress-responsive genes. Numbers of transcription factor are involved in regulating the expression of ABA responsive genes by acting together with their respective cis-acting elements. Hence, for improvement in stress-tolerance capacity of plants, it is necessary to understand the mechanism behind it. On this ground, this article enlightens the importance and role of ABA signaling with regard to various stresses as well as regulation of ABA biosynthetic pathway along with the transcription factors for stress tolerance.

8.
Front Microbiol ; 8: 07, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28184215

RESUMEN

Nanotechnology is a cutting-edge field of science with the potential to revolutionize today's technological advances including industrial applications. It is being utilized for the welfare of mankind; but at the same time, the unprecedented use and uncontrolled release of nanomaterials into the environment poses enormous threat to living organisms. Silver nanoparticles (AgNPs) are used in several industries and its continuous release may hamper many physiological and biochemical processes in the living organisms including autotrophs and heterotrophs. The present review gives a concentric know-how of the effects of AgNPs on the lower and higher autotrophic plants as well as on heterotrophic microbes so as to have better understanding of the differences in effects among these two groups. It also focuses on the mechanism of uptake, translocation, accumulation in the plants and microbes, and resulting toxicity as well as tolerance mechanisms by which these microorganisms are able to survive and reduce the effects of AgNPs. This review differentiates the impact of silver nanoparticles at various levels between autotrophs and heterotrophs and signifies the prevailing tolerance mechanisms. With this background, a comprehensive idea can be made with respect to the influence of AgNPs on lower and higher autotrophic plants together with heterotrophic microbes and new insights can be generated for the researchers to understand the toxicity and tolerance mechanisms of AgNPs in plants and microbes.

9.
J Therm Biol ; 63: 58-64, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28010816

RESUMEN

Skin is most important environmental interface providing a protective envelope to animals. It's always under the influence of both internal and external stressors. Heat shock proteins (HSP) are highly conserved stress proteins which play crucial roles in environmental stress tolerance and thermal adaptation. Present study was planned to observe the relative mRNA expression of inducible (HSP70.1 and HSP70.2) and constitutive (HSP70.8) HSP in skin of zebu (Tharparkar) and crossbred (Karan Fries) cattle during different seasons. Skin biopsies were collected from rump region of each animal, aseptically during winter, spring and summer season. Quantitative real time polymerase chain reaction was performed to examine the gene expression of constitutive (HSP70.8) and inducible (HSP70.1 and HSP70.2) HSP in skin of both the breeds during different seasons. Present study observed higher expression of both constitutive and inducible HSP genes in both the breeds during summer and winter than spring season, but magnitude of increase was higher during summer than winter. During summer season, expression pattern of HSPs in skin showed breed differences, where constitutive HSP expression was higher in Tharparkar than Karan Fries and that of inducible HSP was higher in Karan Fries than Tharparkar. Hence, present study suggested that HSP may be conveniently used as biomarkers for assessing protective response of skin against heat stress in zebu and crossbred cattle. Variation in expression between breeds is associated with their heat tolerance and thermal adaptability. In summary, skin of zebu cattle (Tharparkar) is more resistant to summer stress than crossbred (Karan Fries), providing greater protection against heat stress during summer season. Superior skin protective mechanism of zebu (Tharparkar) than crossbred (Karan-Fries) cattle against heat stress may contribute to superior adaptability of zebu cattle to tropical climatic conditions than crossbreed.


Asunto(s)
Bovinos/genética , Quimera , Proteínas del Choque Térmico HSP72/metabolismo , Respuesta al Choque Térmico , Piel/metabolismo , Clima Tropical , Aclimatación , Animales , Bovinos/metabolismo , Bovinos/fisiología , Proteínas del Choque Térmico HSP72/genética , Estaciones del Año
10.
Vet World ; 9(10): 1051-1055, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27847412

RESUMEN

AIM: To investigate the effect of temperature-humidity index (THI) on the expression pattern of heat-shock protein 72 (HSP72) mRNA of Sahiwal and Karan-Fries (KF) cattle in different THIs. MATERIALS AND METHODS: Five different periods of a year were selected based on combinations of Tmax/Tmin, viz., P1: <20°C/<10°C; P2: >20°C/<10°C, P3: <30°C/<15°C; P4: >35°C/<20°C, and P5: >35°C/>20°C. The THI was calculated from the records of temperature and relative humidity in different periods. Heart rate variability (HRV) was calculated from electrocardiogram records in different periods. HSP72 mRNA expression was estimated by reverse transcription polymerase chain reaction. RESULTS: The THI recorded during P1, P2, P3, P4, and P5 were 55.5, 60.3, 70.1, 74.5, and 79.0, respectively. THI in P4 and P5 were stressful to animals. HSP72 mRNA expression increased during cold stress in P1 in Sahiwal and heat stress in P4 and P5 in both Sahiwal and KF. Sahiwal maintained increased HSP72 mRNA expression longer than KF without causing a significant change in HRV. CONCLUSION: Both low THI in winter and high THI in summer increased HSP72 mRNA of Sahiwal and KF without significant change in HRV. Thermotolerance of Sahiwal could be due to the maintenance of higher HSP72 expression longer than KF in prolonged heat stress in summer.

11.
Int J Biometeorol ; 60(9): 1357-66, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26781547

RESUMEN

In vitro environments like heat stress usually increase the production of reactive oxygen species in bubaline oocytes which have been implicated as one of the major causes for reduced developmental competence. Oocytes during meiotic maturation are sensitive to oxidative stress, and heat stress accelerates cellular metabolism, resulting in the higher production of free radicals. Therefore, the aim of present work was to assess the impact of heat stress during meiotic maturation on bubaline cumulus-oocyte complexes (COC), denuded oocytes (DO), and cumulus cell mass in terms of their oxidative status. Accordingly, for control group, COC were matured at 38.5 °C for complete 24 h of meiotic maturation and heat stress of 40.5 and 41.5 °C was applied to COC during the first 12 h of maturation and then moved to 38.5 °C for rest of the 12 h. In another group, COC after maturation were denuded from the surrounding cumulus cells by manual pipetting. Results indicated that the production of reactive oxygen species (ROS), lipid peroxides, and nitric oxide (NO) was significantly (P < 0.05) higher in the oocytes subjected to heat stress (40.5 and 41.5 °C) during meiotic maturation compared to the oocytes matured under standard in vitro culture conditions (38.5 °C). Also, the antioxidant enzymatic activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase were significantly (P < 0.05) increased in all the treatment groups compared to the control group. Therefore, the present study clearly establishes that heat stress ensues oxidative stress in bubaline oocytes which triggers the induction of antioxidant enzymatic defense system for scavenging the ROS.


Asunto(s)
Calor/efectos adversos , Oocitos , Animales , Búfalos , Catalasa/metabolismo , Procesos de Crecimiento Celular , Femenino , Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Glutatión Reductasa/metabolismo , Peróxidos Lipídicos/metabolismo , Meiosis , Óxido Nítrico/metabolismo , Oocitos/citología , Oocitos/enzimología , Oocitos/crecimiento & desarrollo , Oocitos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismo
12.
Int J Biometeorol ; 60(6): 873-82, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26476524

RESUMEN

The aim of this study was to evaluate the genome integrity so as to assess the adaptability of three breeds of indigenous cattle reared under arid and semi-arid regions of Rajasthan (Bikaner) and Haryana (Karnal) India. The cattle were of homogenous group (same age and sex) of indigenous breeds viz. Sahiwal, Tharparkar and Kankrej. A total of 100 animals were selected for this study from both climatic conditions. The sister chromatid exchanges (SCE's), chromosomal gaps and chromatid breaks were observed in metaphase plates of chromosome preparations obtained from in vitro culture of peripheral blood lymphocytes. The mean number of breaks and gaps in Sahiwal and Tharparkar of semi-arid zone were 8.56 ± 3.16, 6.4 ± 3.39 and 8.72 ± 2.04, 3.52 ± 6.29, respectively. Similarly, the mean number of breaks and gaps in Tharparkar and Kankrej cattle of arid zone were 5.26 ± 1.76, 2.74 ± 1.76 and 5.24 ± 1.84, 2.5 ± 1.26, respectively. The frequency of SCEs in chromosomes was found significantly higher (P < 0.05) in Tharparkar of semi-arid region (4.72 ± 1.55) compared to arid region (2.83 ± 1.01). Similarly, the frequency of SCEs was found to be 4.0 ± 1.41 in the Sahiwal of semi-arid region and 2.69 ± 1.12 in Kankrej of arid zone. Statistical analysis revealed significant differences (P < 0.05) amongst the different zones, i.e. arid and semi-arid, whereas no significant difference (P > 0.05) was observed in the same zone. The analysis of frequency of CAs and SCEs revealed significant effects of environmental conditions on the genome integrity of animals, thereby indicating an association with their adaptability.


Asunto(s)
Aberraciones Cromosómicas , Clima , Intercambio de Cromátides Hermanas , Adaptación Fisiológica , Animales , Bovinos/sangre , Bovinos/genética , Células Cultivadas , Análisis Citogenético , Femenino , India , Linfocitos
13.
J Therm Biol ; 51: 55-64, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25965018

RESUMEN

Heat shock proteins consist of highly conserved stress proteins, expressed in response to stress and play crucial roles in environmental stress tolerance and adaptation. The present study was conducted to identify major types of genes under the HSP70 family and other HSPs and to evaluate their expression pattern in Sahiwal and Tharparkar breeds of zebu cattle (Bos indicus) and Murrah buffalo (Bubalus bubalis) with respect to different seasons. Quantitative real time polymerase chain reaction was performed to analyze the transcript variants of three HSP70 family genes (HSPA1A, HSPA1B, and HSPA8) and HSP10, HSP60, HSP90 and HSF1 in each breed. The major finding of this study was the higher abundance of all the studied HSP genes during summer and winter compared to spring season, but the magnitude of increase was higher during summer as compared to winter. HSPA1A and HSPA1B genes showed maximal induction (P<0.001) during summer and winter while HSP60 and HSP10 were found to be the second most abundantly expressed HSPs. The relative mRNA abundance of HSF1 significantly increased (P<0.001) in Murrah buffalo compared to Tharparkar and Sahiwal cattle during summer and winter. Expression pattern of heat shock protein genes indicated that amongst the breeds, the expression was higher in Murrah buffalo compared to Sahiwal and Tharparkar cattle, thereby indicating the more adaptive capacity of later during periods of stress. Hence, this study suggests that heat shock protein genes may be conveniently used as biomarkers for assessing stress response in cattle and buffalo and the expression is species and breed-specific. Furthermore, the variation in expression is associated with heat tolerance and adaptation to different climatic conditions.


Asunto(s)
Aclimatación/genética , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Estaciones del Año , Clima Tropical , Animales , Búfalos , Bovinos , Proteínas de Choque Térmico/sangre , Respuesta al Choque Térmico/genética , ARN Mensajero/metabolismo , Transcriptoma
14.
Ultrasonics ; 60: 126-32, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25791205

RESUMEN

The paper reports the study of magnetic field induced structures in magnetic nanofluid investigated through ultrasonic wave propagation. Modified Tarapov's theory is used to study variation in velocity anisotropy with magnetic field. The types of field induced structures depend upon the chemical structure of the carrier in which magnetic nanoparticles are dispersed. Our study indicates formation of fractals and chain respectively, in transformer oil and kerosene based fluid. This difference is explained on the basis of particle-particle interaction and particle-medium interaction.

15.
Iran J Vet Res ; 16(2): 137-43, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-27175165

RESUMEN

The study was conducted to evaluate the effect of thermal stress on expression profile of genes related to apoptosis in peripartum Sahiwal cows. For this, twelve pregnant dry Sahiwal cows were selected from Livestock Research Centre at National Dairy Research Institute, Karnal. The cows were divided into two groups consisting of six Sahiwal cows each. Cows of group I calved during thermoneutral temperature conditions (THI=67.3) and cows of group II calved in summer season (THI=79.9). Blood samples were collected on -15, 0 and +15 days with respect to calving where day '0' represents the day of calving. The peripheral blood mononuclear cells (PBMC) were separated and total RNA was isolated for the BCL-2 (B-Cell Lymphoma-2), BAX (BCL-2 antagonist killer-1), BAK (Bcl-2-associated X protein), CASP-3 (cysteine-aspartic proteases-3) and P53 (tumour protien-53) mRNAs expression. It was found that there was up regulation of CASP-3 on the day of calving during both temperature conditions. Comparison between the two temperature conditions showed that expression of CASP-3, BCL-2, BAK, P53 and ratio of BAX/BCL-2 in PBMC increased during summer as compared to thermoneutral condition suggesting the susceptibility of these cells to apoptosis. Based on the above findings it can be concluded that during calving PBMC are more susceptible to apoptosis, and summer being more stressful potentiates the apoptosis of PBMC in Sahiwal cows.

16.
Oral Dis ; 21(1): 38-45, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24267395

RESUMEN

OBJECTIVE: Cyclooxygenase-2 (COX-2) enzyme is a major mediator of inflammation in periodontitis, leading to loss of gingival tissues and alveolar bone supporting the teeth. Previous studies have explored the role of COX-2 polymorphisms with the risk of periodontitis in different ethnic groups; however, findings are inconsistent. So, we aimed to investigate the association of COX-2 polymorphisms (rs20417, rs689466, and rs5275) in susceptibility to chronic periodontitis (CP) in northern Indian population. Meta-analysis was also carried out to precisely estimate the effect of COX-2 polymorphisms in CP. MATERIALS AND METHODS: Genotyping of COX-2 polymorphisms was carried out through PCR-RFLP in 200 CP cases and 200 controls. For risk estimation, binary logistic regression was applied using SPSS, version 15.0, while meta-analysis was carried using MIX 2.0 software. RESULTS: None of the COX-2 polymorphisms independently were associated with the risk of CP. Meta-analysis suggested a significant reduced risk of CP with rs5275+8473 C allele and rs20417 in Chinese population. CONCLUSIONS: No association was observed in any of the studied COX-2 polymorphisms with CP in North India. But, the study should be replicated in larger sample size to arrive at a definitive conclusion. Meta-analysis suggested a role of rs5275 COX-2 polymorphisms in susceptibility to overall CP, and on ethnic basis, rs20417 showed reduced risk of CP in Chinese population.


Asunto(s)
Periodontitis Crónica/genética , Ciclooxigenasa 2/genética , Predisposición Genética a la Enfermedad/genética , Polimorfismo de Nucleótido Simple/genética , Adulto , Estudios de Casos y Controles , Periodontitis Crónica/epidemiología , Femenino , Estudios de Asociación Genética , Humanos , India/epidemiología , Masculino , Factores de Riesgo
17.
Niger Postgrad Med J ; 21(2): 128-35, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25126866

RESUMEN

UNLABELLED: This study aimed to assess the effect of a short school-based anti-smoking program on the knowledge, attitude and practice of cigarette smoking among students in secondary schools in Lagos State. SUBJECTS AND METHODS: A non-randomized, controlled intervention study was done among respondents selected using multi-stage sampling. Baseline data was collected using self-administered questionnaires. An anti-smoking awareness programme was carried out among students in the intervention group using health talks, information leaflets and posters. Post-intervention data collection took place three months later. RESULTS: There were significant increments in the mean knowledge and attitude scores after the intervention. There was however no statistically significant change in the current smoking habits of respondents (4% vs. 3%; p=0.41)in the intervention group. Nevertheless, in the intervention group, the number of never- smokers who reported that they were likely to initiate cigarette smoking within the next year significantly reduced. There was also a significant increase in the proportion of current smokers who desired to quit smoking. CONCLUSION: Even brief anti-smoking programs of this nature are effective at improving the knowledge and modifying the attitude of the respondents but do not improve smoking habits. It however motivated the desire to quit among current smokers. Health education sessions and periodic anti-smoking programmes should be introduced into the secondary school curriculum. More intensive approaches may be needed to influence the smoking behaviour of adolescent smokers.


Asunto(s)
Conducta del Adolescente , Educación en Salud , Conocimientos, Actitudes y Práctica en Salud , Prevención del Hábito de Fumar , Estudiantes/psicología , Adolescente , Niño , Femenino , Humanos , Masculino , Nigeria , Instituciones Académicas , Fumar/psicología , Encuestas y Cuestionarios , Adulto Joven
18.
J Pediatr Urol ; 10(6): 1238-43, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25130900

RESUMEN

OBJECTIVE: To investigate the feasibility of correcting coexistent penile torsion and chordee without hypospadias by mobilization of the urethra and spongiosum. MATERIALS AND METHODS: A retrospective study of nine patients with simultaneous penile torsion and chordee without hypospadias was undertaken between January 2006 and December 2012. During this period, a total of 364 cases of hypospadias and 38 of chordee without hypospadias were operated on, making a total of 402 patients with hypospadias-related complexes. The same steps were used for correction of both torque and chordee. After a circumcoronal incision, the penis was fully degloved and the spongiosum with urethra was lifted up off the cavernosa. Next, mobilization of the hypoplastic urethra with spongiosum was extended into the glans. If chordee or torque persisted, urethral mobilization was performed proximally up to the bulbar urethra, as required. Spongioplasty and glansplasty were done and a per-urethral stent was kept in for three to five days. RESULTS: The age of the patients ranged from 5 to 16 years (median 6 years). Penile torsion ranged from 30° to 120°, with a median of 75°. Ventral chordee ranged from 45° to 100°, with a median of 50°. A ratio of 1:9.6 was found for chordee without hypospadias compared to the total hypospadias cases, with an incidence of 9.5%. The ratio of chordee without hypospadias with torsion compared to the total hypospadias cases was 1:29. There was an incidence of chordee without hypospadias with penile torsion of 3.5% in all patients with hypospadias. The ratio of chordee without hypospadias with torsion to only chordee without hypospadias was 1:1.71, with an incidence of 37.0%. Every step contributed to the correction of curvature and torsion. Chordee was corrected in two patients by penile degloving and lifting of the spongiosa off the urethral plate; three patients required additional mobilization of the urethra into the glans. Another two patients needed proximal urethral mobilization and one required a dorsal plication. In five patients, torque was corrected by penile degloving, lifting of the spongiosa and mobilization of the urethra into the glans; four patients required further proximal urethral mobilization. All patients had excellent functional and cosmetic results. No residual chordee or torque was observed in any patient on follow-up at 12-24 months. CONCLUSION: The technique of distally mobilizing a hypoplastic urethra with spongiosum from the corpora into the glans, and proximally up to the bulbar region corrects moderate to severe chordee and torsion with excellent cosmetic results. The incidence of torsion with chordee without hypospadias was 3.5% of all cases of hypospadias.


Asunto(s)
Enfermedades del Pene/cirugía , Pene/anomalías , Anomalía Torsional/cirugía , Adolescente , Niño , Preescolar , Estudios de Factibilidad , Humanos , Masculino , Estudios Retrospectivos , Técnicas de Sutura , Uretra/cirugía , Procedimientos Quirúrgicos Urológicos Masculinos/métodos
19.
J Assist Reprod Genet ; 31(10): 1349-60, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24938361

RESUMEN

OBJECTIVE: To determine the direct effect of physiologically relevant high temperatures (40.5 and 41.5 °C) for two time periods (12 and 24 h) on bubaline oocytes during in vitro maturation. METHOD: The control group oocytes were cultured at 38.5 °C for 24 h. The treatment 1 (T1) and 3 (T3) group oocytes were cultured at 40.5 and 41.5 °C respectively, for the first 12 h and at 38.5 °C for rest of the 12 h. However, treatment 2 (T2) and 4 (T4) group oocytes were cultured at 40.5 and 41.5 °C for complete 24 h. RESULTS: Development of oocytes to blastocyst was severely compromised (p < 0.001) when matured at 40.5 and 41.5 °C for both exposure periods (12 h and 24 h). It was found that the cleavage rates, blastocyst yield and mean cell number decreased remarkably (p < 0.001) in the treatment groups compared to control. The relative mRNA expression of heat shock protein (Hsp 70.1, 70.2, 70.8, 60, 10 and HSF1), pro-apoptotic (caspases-3, -7, -8, Bid and Bax) and oxidative stress (iNOS) related genes was significantly higher (p < 0.05) in all the treatment groups compared to control. However, mRNA abundance of anti-apoptotic (Bcl-2, Mcl-1, Bcl-xl), glucose transport (Glut1, Glut3 and IGF1R), developmental competence (ZAR1 and BMP15) and oxidative stress (MnSOD) related genes was significantly decreased (p < 0.05) in the treatment groups compared to control. CONCLUSION: The present study clearly establishes that physiologically relevant elevated temperatures during in vitro meiotic maturation reduce developmental competence of bubaline oocytes.


Asunto(s)
Búfalos/fisiología , Meiosis/fisiología , Oocitos/fisiología , Animales , Apoptosis/genética , Apoptosis/fisiología , Blastocisto/fisiología , Búfalos/genética , Proteínas de Choque Térmico/genética , Calor , Meiosis/genética , Estrés Oxidativo/genética , ARN Mensajero/genética
20.
J Therm Biol ; 43: 46-53, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24956957

RESUMEN

The present studies were conducted to investigate the difference response of dermal fibroblasts to heat stress in Tharparkar and Karan-Fries cattle. Skin is the most important environmental interface providing a protective envelope to animals. In skin, dermal fibroblasts are the most regular cell constituent of dermis that is crucial for temperature homeostasis. The study aimed to examine the reactive oxygen species (ROS) formation, cytotoxicity (%) and heat shock protein 70 (HSP70) genes expression in dermal fibroblast of Tharparkar and Karan-Fries cattle and to assess whether resistance of dermal fibroblast to heat stress is breed specific. Dermal fibroblasts from ear pinna of Tharparkar and Karan-Fries cattle were exposed at 25 °C, 37 °C, 40 °C and 44 °C for 3 h to measure the ROS, cytotoxicity (%) and HSP 70 (HSPA1A, HSPA2 and HSPA8) genes' expression. The results showed that ROS formation at low temperature (25 °C) decreased in both breeds as compared to control (37 °C) and the differences were significant (P<0.0001). Heat stress at 40 °C did not increase ROS formation significantly in Tharparkar but increased significantly (P<0.001) in Karan-Fries cattle. The overall cytotoxicity (%) was also found to be significantly different (P<0.001) between Tharparkar and Karan-Fries cattle, and on exposure to different temperatures (P<0.001). The cytotoxicity (%) in dermal fibroblast cells of Karan-fries cows was more than Tharparkar. The expression studies indicated that all HSP70 genes (HSPA8, HSPA1A and HSPA2) were up-regulated at different temperatures in both breeds. In Tharparkar, the relative mRNA expression of HSPA8 gene was higher but HSPA1A and HSPA2 genes were low as compared to Karan-Fries cattle. At 40 and 44 °C, the relative expressions of inducible HSP 70 genes (HSPA1A and HSPA2) were higher in Karan-Fries than Tharparkar. In summary, dermal fibroblast resistance to heat shock differed between breeds. Dermal fibroblasts of Tharparkar were observed to be more heat tolerant than crossbred Karan-Fries cattle. The study concludes that zebu cattle (Tharparkar) dermal fibroblasts are more adapted to tropical climatic condition than crossbreed cattle (Karan-Fries). Differences exist in dermal fibroblasts of heat adapted and non-adapted cattle.


Asunto(s)
Aclimatación/fisiología , Fibroblastos/metabolismo , Proteínas HSP70 de Choque Térmico/genética , Respuesta al Choque Térmico/fisiología , Piel/citología , Animales , Regulación de la Temperatura Corporal/fisiología , Bovinos , Supervivencia Celular , Femenino , Regulación de la Expresión Génica , Proteínas HSP70 de Choque Térmico/metabolismo , Especies Reactivas de Oxígeno/metabolismo
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