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1.
Work ; 78(1): 131-152, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38517835

RESUMEN

BACKGROUND: This study focuses on evaluating the exposure to whole-body vibration (WBV) and association of musculoskeletal disorders (MSDs) with various risk factors among dumper operators in the mining industry. Despite the issue's significance, prior research has been limited. OBJECTIVE: The study introduces a novel fuzzy-based approach for identifying, selecting, and prioritizing safety measures to mitigate MSD risks. METHODS: Data collection comprised face-to-face interviews, anthropometric measurements, Rapid Upper Limb Assessment (RULA) scoring for posture assessment, and the Nordic Musculoskeletal questionnaire for assessment of MSD prevalence. Multiple linear and logistic regression models were used to analyse the contributing risk factors to MSDs and WBV exposure. These risk factors formed the basis for a practical approach to select appropriate safety measures based on fuzzy based aggregation method of expert's judgment aimed at mitigating the risk of MSDs. RESULTS: The results revealed that the risk factors such as poor work posture, WBV exposure and poor seat design were significantly associated with neck (adjusted odds ratio aOR = 4.81), upper limb and shoulder (aOR = 3.28), upper back (aOR = 5.09), and lower back pain (aOR = 3.67) at p < 0.05. Using these factors to formulate safety measures to reduce MSD risk, the minimization of sharp turns and abrupt changes in elevation in designing the haul roads, scheduled maintenance practices, and ergonomic seat design were found as important safety measures in this study. CONCLUSION: Our unique methodological approach in occupational health research could be highly beneficial for tailoring safety measures at the unit level with minimal effort.


Asunto(s)
Minería , Enfermedades Musculoesqueléticas , Humanos , Enfermedades Musculoesqueléticas/prevención & control , Enfermedades Musculoesqueléticas/epidemiología , Enfermedades Musculoesqueléticas/etiología , Masculino , Adulto , Encuestas y Cuestionarios , Factores de Riesgo , Persona de Mediana Edad , Lógica Difusa , Femenino , Hierro , Enfermedades Profesionales/prevención & control , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/etiología , Postura , Ergonomía/métodos , Prevalencia , Vibración/efectos adversos , Exposición Profesional/prevención & control , Exposición Profesional/efectos adversos , Exposición Profesional/estadística & datos numéricos
2.
Int J Occup Saf Ergon ; 30(1): 41-55, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36519241

RESUMEN

Objectives. Studies related to a systematic approach for intervention design to reduce whole-body vibration (WBV) exposure are scarce. This study presents a systematic approach to identifying, selecting and prioritizing safety interventions to fulfill that research gap. Methods. A total of 130 vibration readings for dumper operators were taken from two surface iron ore mines to identify significant determinants of WBV exposure. Initially, age, weight, seat design, awkward posture, machine's age, load tonnage, dumper speed and haul road condition were hypothesized as determinants. Data were collected through standardized questionnaires and field-based observation. A multivariate statistical approach was applied for the practical use of the intervention program. Results. As some of the hypothesized factors were correlated, exploratory factor analysis (EFA) followed by multiple linear regression (MLR) was used to investigate their association with WBV exposure. As per EFA results, hypothesized factors were clubbed under individual, ergonomics and occupational factors. Occupational and ergonomics factors were found to be significantly associated with WBV exposure through MLR and used to form safety interventions to reduce WBV exposure. Conclusions. Our methodological approach is original in the occupational health research area and can be helpful to tailor the safety interventions for the unit level with minimum effort.


Asunto(s)
Exposición Profesional , Salud Laboral , Humanos , Vibración/efectos adversos , Exposición Profesional/prevención & control , Exposición Profesional/análisis , Vehículos a Motor , Ergonomía
3.
J Org Chem ; 88(24): 16960-16966, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38048482

RESUMEN

The N-alkylation of amines with alcohols using earth-abundant and nonprecious metal catalysts has gained considerable attention in the pharmaceutical industry. We described titanium-catalyzed synthetic protocol for N-alkylation of amines with alcohols via borrowing hydrogen or hydrogen autotransfer reactions. The methodology enables the selective monoalkylation of various substituted (hetero)aromatic amines in good to excellent yields (up to 97% yield). The importance of the protocol was further demonstrated by the applicability of earth-abundant metal catalysis and the synthesis of 32 N-alkylated amines. The work allows the utilization of titanium-based catalysts for various reactions to expand the nature blueprint in catalysis.

4.
Artículo en Inglés | MEDLINE | ID: mdl-37022027

RESUMEN

Schizophrenia (SCZ) is a serious mental condition that causes hallucinations, delusions, and disordered thinking. Traditionally, SCZ diagnosis involves the subject's interview by a skilled psychiatrist. The process needs time and is bound to human errors and bias. Recently, brain connectivity indices have been used in a few pattern recognition methods to discriminate neuro-psychiatric patients from healthy subjects. The study presents Schizo-Net, a novel, highly accurate, and reliable SCZ diagnosis model based on a late multimodal fusion of estimated brain connectivity indices from EEG activity. First, the raw EEG activity is pre-processed exhaustively to remove unwanted artifacts. Next, six brain connectivity indices are estimated from the windowed EEG activity, and six different deep learning architectures (with varying neurons and hidden layers) are trained. The present study is the first which considers a large number of brain connectivity indices, especially for SCZ. A detailed study was also performed that identifies SCZ-related changes occurring in brain connectivity, and the vital significance of BCI is drawn in this regard to identify the biomarkers of the disease. Schizo-Net surpasses current models and achieves 99.84% accuracy. An optimum deep learning architecture selection is also performed for improved classification. The study also establishes that Late fusion technique outperforms single architecture-based prediction in diagnosing SCZ.

5.
Artículo en Inglés | MEDLINE | ID: mdl-37027569

RESUMEN

Non-invasive Visual Stimuli evoked-EEG-based P300 BCIs have gained immense attention in recent years due to their ability to help patients with disability using BCI-controlled assistive devices and applications. In addition to the medical field, P300 BCI has applications in entertainment, robotics, and education. The current article systematically reviews 147 articles that were published between 2006-2021*. Articles that pass the pre-defined criteria are included in the study. Further, classification based on their primary focus, including article orientation, participants' age groups, tasks given, databases, the EEG devices used in the studies, classification models, and application domain, is performed. The application-based classification considers a vast horizon, including medical assessment, assistance, diagnosis, applications, robotics, entertainment, etc. The analysis highlights an increasing potential for P300 detection using visual stimuli as a prominent and legitimate research area and demonstrates a significant growth in the research interest in the field of BCI spellers utilizing P300. This expansion was largely driven by the spread of wireless EEG devices, advances in computational intelligence methods, machine learning, neural networks and deep learning.


Asunto(s)
Interfaces Cerebro-Computador , Humanos , Atención , Electroencefalografía/métodos , Potenciales Relacionados con Evento P300/fisiología , Redes Neurales de la Computación
6.
IEEE Access ; 10: 23167-23185, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35360503

RESUMEN

Deep learning-based Computer-Aided Diagnosis has gained immense attention in recent years due to its capability to enhance diagnostic performance and elucidate complex clinical tasks. However, conventional supervised deep learning models are incapable of recognizing novel diseases that do not exist in the training dataset. Automated early-stage detection of novel infectious diseases can be vital in controlling their rapid spread. Moreover, the development of a conventional CAD model is only possible after disease outbreaks and datasets become available for training (viz. COVID-19 outbreak). Since novel diseases are unknown and cannot be included in training data, it is challenging to recognize them through existing supervised deep learning models. Even after data becomes available, recognizing new classes with conventional models requires a complete extensive re-training. The present study is the first to report this problem and propose a novel solution to it. In this study, we propose a new class of CAD models, i.e., Deep-Precognitive Diagnosis, wherein artificial agents are enabled to identify unknown diseases that have the potential to cause a pandemic in the future. A de novo biologically-inspired Conv-Fuzzy network is developed. Experimental results show that the model trained to classify Chest X-Ray (CXR) scans into normal and bacterial pneumonia detected a novel disease during testing, unseen by it in the training sample and confirmed to be COVID-19 later. The model is also tested on SARS-CoV-1 and MERS-CoV samples as unseen diseases and achieved state-of-the-art accuracy. The proposed model eliminates the need for model re-training by creating a new class in real-time for the detected novel disease, thus classifying it on all subsequent occurrences. Second, the model addresses the challenge of limited labeled data availability, which renders most supervised learning techniques ineffective and establishes that modified fuzzy classifiers can achieve high accuracy on image classification tasks.

7.
Work ; 71(1): 235-247, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34924417

RESUMEN

BACKGROUND: Dumper operators in mines worldwide are subjected to Musculoskeletal Disorders (MSDs) due to whole-body vibration exposure. This study evaluated the working-life-Whole-Body Vibration (WBV)-exposure and their association with various MSDs among dumper operators in mines which remains poorly addressed. METHODS: This case-control study in Indian iron ore mines was conducted to compare randomly selected 65 dumper operators and 65 office workers. Data were collected through face-to-face interviews using the Nordic Musculoskeletal Questionnaire (NMQ) and were analysed using logistic regression models. RESULTS: The study revealed that majority of the dumper operators were exposed to WBV exceeding the ISO-2631 limits. Compared with controls, the dumper operators had a much higher risk of upper back pain (age-overweight-adjusted odds ratio ORao = 5.37, 95% CI = 1.78-16.20), lower back pain (ORao = 2.72, 95% CI = 1.25-5.94), knee and leg pain (ORao = 3.68, 95% CI = 1.22-11.11), and having 2+ MSDs (ORao = 5.05, 95% CI = 1.88-13.51, vs. no MSDs). Working-life-WBV-exposure was higher among dumper operators having upper back pain (mean (SD) = 7.1 (1.91) vs. 5.7 (1.91), p < 0.01) and lower back pain (mean (SD) = 6.63 (2.10) vs. 5.55 (1.71), p < 0.01) compared to those without these MSDs. Older age was associated with higher risk of MSD pains. CONCLUSION: Dumper operators have excess MSDs due to high working-life-WBV-exposure. Their MSDs and working-life-WBV-exposure should be regularly evaluated and reduced.


Asunto(s)
Dolor de la Región Lumbar , Enfermedades Musculoesqueléticas , Enfermedades Profesionales , Exposición Profesional , Anciano , Estudios de Casos y Controles , Humanos , Hierro , Dolor de la Región Lumbar/epidemiología , Dolor de la Región Lumbar/etiología , Enfermedades Musculoesqueléticas/epidemiología , Enfermedades Musculoesqueléticas/etiología , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/etiología , Exposición Profesional/efectos adversos , Exposición Profesional/análisis , Vibración/efectos adversos
8.
ACS Omega ; 6(39): 25381-25388, 2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-34632196

RESUMEN

Macrocyclic lactones have redolent characteristics of muscones that originate from the rectal musk organs of the musk deer. These lactones are the primary raw material in the flavor and fragrance industry and are also found within the cyclic frameworks of various bioactive molecules. Due to great demand, many efforts have been made for their synthesis; however, strategies generating a large number of macrocyclic analogues from renewable resources have not been fully realized and are urgently required. Here, we outline a sustainable, straightforward, and eco-friendly approach to synthesize high-valued macrocyclic lactones utilizing olive oil under greener reaction conditions. The outlined method allows us to turn biomass into valuable 12- to 29-membered lactones and dilactones.

9.
Chem Commun (Camb) ; 57(44): 5430-5433, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33949501

RESUMEN

The development of green and sustainable processes to synthesize active pharmaceutical ingredients and key starting materials is a priority for the pharmaceutical industry. A green and sustainable protocol for the oxidative cleavage of olefins to produce pharmaceutically and biologically valuable carboxylic acids is achieved. The developed protocol involves 70% aq. TBHP as an oxidant over a heterogeneous vanadium catalyst system. Notably, the synthesis of industrially important azelaic acid from various renewable vegetable oils is accomplished. The catalyst could be recycled for up to 5 cycles without significant loss in yield and the protocol was successfully demonstrated at the gram-scale.

10.
ACS Comb Sci ; 22(9): 440-445, 2020 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-32691584

RESUMEN

Conjugates between pharmaceuticals and small molecules enable access to a vast chemical space required for the discovery of new lead molecules with modified therapeutic potential. However, the dearth of specific chemical reactions that are capable of functionalizing drugs and bioactive natural products presents a formidable challenge for preparing their conjugates. Here, we report a support-free CuI-nanoparticle-catalyzed strategy for conjugating electron-deficient and electron-rich terminal alkynes with a ciprofloxacin methyl ester. Our conjugation technique exploits the late-stage functionalization of bioactive natural products such as tocopherol, vasicinone, amino acids, and pharmaceuticals such as aspirin and paracetamol to provide conjugates in excellent yields under mild and green conditions. This protocol also enabled the synthesis of (hetero)arene-ciprofloxacin 1,4-disubstituted 1,2,3-triazoles in good yields and high regioselectivities. These synthesized ciprofloxacin conjugates were evaluated in vitro for their antibacterial activity against a panel of relevant bacteria. A significant number of conjugates showed comparable activity against Gram-positive and Gram-negative bacteria. Moreover, some conjugates exhibited less toxicity than ciprofloxacin against two mammalian cell lines, suggesting the utility for the future investigation of these compounds for in vivo efficacy and pharmacokinetic studies.


Asunto(s)
Alquinos/farmacología , Antibacterianos/farmacología , Azidas/farmacología , Ciprofloxacina/farmacología , Bibliotecas de Moléculas Pequeñas/farmacología , Alquinos/síntesis química , Alquinos/química , Antibacterianos/síntesis química , Antibacterianos/química , Azidas/síntesis química , Azidas/química , Ciprofloxacina/química , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Bibliotecas de Moléculas Pequeñas/síntesis química , Bibliotecas de Moléculas Pequeñas/química
11.
J Clin Orthop Trauma ; 11(Suppl 3): S362-S367, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32523294

RESUMEN

OBJECTIVE: to assess twenty two cases of isolated PCL avulsion fractures from tibial insertion, arthroscopically treated with suture pull technique, and to evaluate achieved clinical outcomes in terms of radiographic laxometry (objective) and Lysholm scale (subjective). MATERIAL AND METHOD: Study includes 22 cases operated between April 2014 and March 2017. Patients less than 18 years old, presentation after 3 weeks of injury, concomitant injury in the same limb, with open wounds or with comminuted avulsed fragment were excluded from the study. All cases were MRI proven. All arthroscopic suture fixation technique was used in all cases. Follow up was done at 3 weeks, 6 weeks, 3 months, 6 months and 12 months. Mean follow up was one year. Subjective complaints, Knee flexion, Lysholm score and stress radiographs were noted. RESULTS: Average Lysholm score was 96.3. Seventeen patients had excellent results and Five had good results based on Lysholm scores. In two patients, grade 2 laxity (5-10 mm) was present on stress radiographs but there were no clinical complaints. All patients achieved osseous union and had no functional limitation. Three Patients developed arthrofibrosis initially but gained functional range later. CONCLUSION: Arthroscopic suture fixation method for PCL avulsion fracture from tibia is a good and safe method of choice for fixation.

12.
Eur J Orthop Surg Traumatol ; 30(3): 411-417, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31650335

RESUMEN

PURPOSE: To evaluate femoral tunnel widening in young and active patients undergoing ACL reconstruction with quadrupled hamstring graft with fixation on tibial side performed with a Bioscrew while femoral fixation performed with either a Tight rope Reverse Threaded (RT) or Transfix or another Bioscrew using CT scan. MATERIAL AND METHOD: A total of 100 consecutive patients underwent single-bundle ACL reconstruction from January 2008 to March 2012. Eighty-six out of these were available with us till the final follow-up. Only 20-40-year-old males with unilateral ACL rupture less than a year old, diagnosed clinically and confirmed radiologically by magnetic resonance imaging, were selected for the study. All patients were evaluated clinically as well as radiologically at follow-up of 2 weeks, 1 month, 3 months, 6 months, 1 year and every 6 months thereafter. CT scans were performed at 2 weeks, 6 months, and 1 year postoperatively. The data acquired at the second week were considered as baseline data and were used for comparison with the data acquired at 6 months and 1 year. RESULTS: The dilatation at the aperture was significantly more in the Tight rope RT group as compared to the other two groups (p value 0.019 and 0.021 for sagittal and coronal images, respectively). CONCLUSION: There is no significant difference between the three different fixation modes in context of tunnel enlargement except with Tight rope RT device which leads to statistically significant dilatation at aperture. Future studies with longer follow-up are required to evaluate its clinical implications.


Asunto(s)
Reconstrucción del Ligamento Cruzado Anterior/métodos , Fémur/cirugía , Adulto , Ligamento Cruzado Anterior/diagnóstico por imagen , Ligamento Cruzado Anterior/cirugía , Lesiones del Ligamento Cruzado Anterior/diagnóstico por imagen , Lesiones del Ligamento Cruzado Anterior/rehabilitación , Lesiones del Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior/rehabilitación , Fémur/diagnóstico por imagen , Humanos , Masculino , Dispositivos de Fijación Ortopédica , Estudios Prospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Adulto Joven
13.
ACS Omega ; 4(12): 15101-15106, 2019 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-31552354

RESUMEN

A novel formic acid-assisted rapid and efficient route for C-S bond construction via the thiol-ene reaction has been reported. Exclusively, the anti-Markovnikov product was obtained in good to excellent yield using the developed protocol. Various styrenes and thiols bearing different functionalities were well tolerated. The reaction also provided a good yield of sulfones in a one-pot two-step protocol. The developed method is operationally simple, green, metal-free, solvent-free, and having a high atom economy with high regioselectivity.

14.
Org Lett ; 20(5): 1359-1362, 2018 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-29450997

RESUMEN

The potential of 2-aminoquinazolin-4(3H)-one as an organocatalyst for the activation of aldehydes via noncovalent interaction for the synthesis of tertiary amines using formic acid as a reducing agent is reported for the first time. The developed protocol demonstrated a dilated substrate scope for aromatic and aliphatic amines with aromatic and aliphatic aldehydes. Furthermore, the current method was also fruitful for the derivatization of ciprofloxacin and its derivative in good to excellent yields.

15.
J Clin Orthop Trauma ; 8(Suppl 2): S16-S20, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29158645

RESUMEN

INTRODUCTION: The management of pilon fractures is controversial primarily due to the high rate of complications irrespective of the mode of treatment. Limited internal fixation with external fixation is associated with minimal soft tissue handling. This may reduce the chances of wound dehiscence and infection. This study was designed to evaluate the functional and clinical outcomes in patients treated with limited internal fixation combined with external fixation in pilon fractures. MATERIAL AND METHODS: This study was conducted as a prospective clinical study on 56 skeletally mature patients with closed fractures with poor skin condition, and with open grade 1 and grade 2 distal tibial intra-articular fractures. All patients were treated with combined limited internal fixation and ankle spanning external fixation. RESULTS: All fractures in this series united with an average time period of union of 18.3weeks (ranging from 13 weeks to 30 weeks). There was no non-union in any case. There was malunion in 4 cases, varus malunion (>5 degree) in 2 cases and recurvatum in another 2 cases). Excellent to good functional results were observed in 88% cases based on the modified Ovadia and Beals score. The mean ankle dorsiflexion and planter flexion movements were 10.2±5.3 degrees and 27.4±7.2 degrees respectively. infections occurred in 6 patients which included 4 pin tract infections and 2 superficial wound infection, all 6 healed after removal of pin tract and with oral antibiotics. CONCLUSION: The technique of combined external fixation with internal fixation is safe and effective management option for intra-articular distal tibial fractures.

16.
ACS Appl Mater Interfaces ; 8(19): 11954-68, 2016 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-27108739

RESUMEN

The uniform dispersion of nanoparticles in a polymer matrix, together with an enhancement of interfacial adhesion is indispensable toward achieving better mechanical properties in the nanocomposites. In the context to biomedical applications, the type and amount of nanoparticles can potentially influence the biocompatibility. To address these issues, we prepared high-density polyethylene (HDPE) based composites reinforced with graphene oxide (GO) by melt mixing followed by compression molding. In an attempt to tailor the dispersion and to improve the interfacial adhesion, we immobilized polyethylene (PE) onto GO sheets by nucleophilic addition-elimination reaction. A good combination of yield strength (ca. 20 MPa), elastic modulus (ca. 600 MPa), and an outstanding elongation at failure (ca. 70%) were recorded with 3 wt % polyethylene grafted graphene oxide (PE-g-GO) reinforced HDPE composites. Considering the relevance of protein adsorption as a biophysical precursor to cell adhesion, the protein adsorption isotherms of bovine serum albumin (BSA) were determined to realize three times higher equilibrium constant (Keq) for PE-g-GO-reinforced HDPE composites as compared to GO-reinforced composites. To assess the cytocompatibility, we grew osteoblast cell line (MC3T3) and human mesenchymal stem cells (hMSCs) on HDPE/GO and HDPE/PE-g-GO composites, in vitro. The statistically significant increase in metabolically active cell over different time periods in culture for up to 6 days in MC3T3 and 7 days for hMSCs was observed, irrespective of the substrate composition. Such observation indicated that HDPE with GO or PE-g-GO addition (up to 3 wt %) can be used as cell growth substrate. The extensive proliferation of cells with oriented growth pattern also supported the fact that tailored GO addition can support cellular functionality in vitro. Taken together, the experimental results suggest that the PE-g-GO in HDPE can effectively be utilized to enhance both mechanical and cytocompatibility properties and can further be explored for potential biomedical applications.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Grafito , Células Madre Mesenquimatosas/metabolismo , Nanocompuestos/química , Osteoblastos/metabolismo , Polietileno , Albúmina Sérica Bovina/química , Animales , Bovinos , Línea Celular , Grafito/química , Grafito/farmacología , Humanos , Células Madre Mesenquimatosas/citología , Ratones , Osteoblastos/citología , Polietileno/química , Polietileno/farmacología
17.
Reprod Sci ; 20(10): 1162-74, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23427177

RESUMEN

Tubulobulbar complexes (TBCs), evaginations of mature spermatids, penetrate into the surrounding Sertoli cell cytoplasm of testis seminiferous epithelium during rat spermatogenesis. These structures prepare mature spermatids for their release into the seminiferous tubular lumen via a process called spermiation. Based on their functions of transient attachment and endocytosis, many actin-regulatory and endocytic proteins are associated with TBCs. Previously, exogenous 17ß-estradiol administration to adult male rats showed spermiation failure that was attributed to TBC disruption. To determine the molecular basis of estrogen-induced TBC disruption, we examined the expressions and localizations of actin-regulatory proteins, endocytic proteins, Rho-GTPases, and phosphorylation in TBCs during sperm release. Results demonstrated absence of neural Wiscott Aldrich syndrome protein, cortactin, adaptor-related protein complex 2 sigma-1 subunit, dynamin 2, cell division control protein 42, and phosphocortactin in the concavity of spermatid head where TBCs are present without change in their protein expression levels. Absence of these proteins could have led to collapse of the TBC structure which is involved in its formation and function.


Asunto(s)
Actinas/metabolismo , Citoesqueleto/metabolismo , Estrógenos/farmacología , Proteínas de la Membrana/metabolismo , Espermátides/metabolismo , Testículo/metabolismo , Animales , Citoesqueleto/efectos de los fármacos , Citoesqueleto/patología , Endocitosis/efectos de los fármacos , Endocitosis/fisiología , Estrógenos/toxicidad , Masculino , Ratas , Ratas Sprague-Dawley , Espermátides/efectos de los fármacos , Espermátides/patología , Testículo/efectos de los fármacos , Testículo/patología
18.
Biochim Biophys Acta ; 1834(1): 8-15, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23072795

RESUMEN

Proteomics, an interface of rapidly evolving advances in physics and biology, is rapidly developing and expanding its potential applications to molecular and cellular biology. Application of proteomics tools has contributed towards identification of relevant protein biomarkers that can potentially change the strategies for early diagnosis and treatment of several diseases. The emergence of powerful mass spectrometry-based proteomics technique has added a new dimension to the field of medical research in liver, heart diseases and certain forms of cancer. Most proteomics tools are also being used to study physiological and pathological events related to reproductive biology. There have been attempts to generate the proteomes of testes, sperm, seminal fluid, epididymis, oocyte, and endometrium from reproductive disease patients. Here, we have reviewed proteomics based investigations in humans over the last decade, which focus on delineating the mechanism underlying various reproductive events such as spermatogenesis, oogenesis, endometriosis, polycystic ovary syndrome, embryo development. The challenge is to harness new technologies like 2-DE, DIGE, MALDI-MS, SELDI-MS, MUDPIT, LC-MS etc., to a greater extent to develop widely applicable clinical tools in understanding molecular aspects of reproduction both in health and disease.


Asunto(s)
Endometrio/metabolismo , Genitales Masculinos/metabolismo , Proteoma/metabolismo , Proteómica/métodos , Reproducción/fisiología , Animales , Femenino , Humanos , Infertilidad/metabolismo , Infertilidad/fisiopatología , Masculino
19.
Reprod Biol Endocrinol ; 10: 27, 2012 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-22510523

RESUMEN

Tubulobulbar complexes (TBCs) are actin-based structures that help establish close contact between Sertoli-Sertoli cells or Sertoli-mature germ cells (spermatids) in the seminiferous tubules of the testes. They are actin-rich push-through devices that eliminate excess spermatid cytoplasm and prepare mature spermatids for release into the tubular lumen. Just prior to spermiation, the elongated spermatid interacts with the Sertoli cell via an extensive structure comprising various adhesion molecules called the apical ectoplasmic specialization which is partially replaced by the apical TBC, on the concave surface of the spermatid head. The sperm release process involves extensive restructuring, namely the disassembly and reassembly of junctions at the Sertoli-spermatid interface in the seminiferous epithelium. Based on the presence of different classes of molecules in the TBCs or the defects observed in the absence of TBCs, the main functions attributed to TBCs are elimination of excess spermatid cytoplasm, endocytosis and recycling of junctional molecules, shaping of the spermatid acrosome, and forming transient anchoring devices for mature spermatids before they are released. This review summarizes the recent findings that focus on the role of TBCs in cell cytoskeleton restructuring during sperm release in the testes and the molecular mechanism involved.


Asunto(s)
Actinas/metabolismo , Uniones Adherentes/fisiología , Células de Sertoli/ultraestructura , Espermátides/ultraestructura , Espermatogénesis/fisiología , Espermatozoides/ultraestructura , Proteínas Adaptadoras Transductoras de Señales/fisiología , Animales , Endocitosis/fisiología , Humanos , Masculino , Microtúbulos/metabolismo , Ratas , Epitelio Seminífero/metabolismo , Túbulos Seminíferos/metabolismo , Células de Sertoli/metabolismo , Espermátides/metabolismo , Espermatozoides/metabolismo
20.
Environ Monit Assess ; 184(11): 7065-77, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22203413

RESUMEN

In limnetic ecosystem, water quality depends upon physical, chemical, and biological factors. Effects of temperature, light scattering, and absorption by suspended and dissolved matter, transport, and mixing of nutrients within the lake are the significant factors as far as water quality is concerned. Nutrient loading into the lake and internal cycling of nutrients is always a matter of concern and critical to number of processes. During the winter season, heat and momentum transfer at the lake surface and the temperature-density relation of water destabilize the water column and drive vertical mixing and transport processes. The deepening of the surface layer produces nutrient transfer from the hypolimnion into the euphotic zone of epilimnion. It may also resuspend sediments that would have settled under stratified conditions, or redistribute particles that may still be in suspension. Thus, there exists a complex connection between the hydrodynamics and water quality issues. Present study is an effort to understand how seasonal changes in the limnetic ecosystem regulate the limnochemistry and movement of nutrient. The study revealed that significant variations of nutrients and organic load were observed between epilimnion and hypolimnion during summer season, and the lake was found in hyper-eutrophic condition throughout the study period.


Asunto(s)
Monitoreo del Ambiente , Lagos/química , Nitrógeno/análisis , Fósforo/análisis , Contaminantes Químicos del Agua/análisis , Ecosistema , India , Modelos Químicos , Estaciones del Año , Temperatura , Abastecimiento de Agua/análisis , Abastecimiento de Agua/estadística & datos numéricos
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