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1.
Work ; 78(1): 131-152, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38517835

RESUMO

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.


Assuntos
Mineração , Doenças Musculoesqueléticas , Humanos , Doenças Musculoesqueléticas/prevenção & controle , Doenças Musculoesqueléticas/epidemiologia , Doenças Musculoesqueléticas/etiologia , Masculino , Adulto , Inquéritos e Questionários , Fatores de Risco , Pessoa de Meia-Idade , Lógica Fuzzy , Feminino , Ferro , Doenças Profissionais/prevenção & controle , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Postura , Ergonomia/métodos , Prevalência , Vibração/efeitos adversos , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/estatística & dados numéricos
2.
Int J Occup Saf Ergon ; 30(1): 41-55, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36519241

RESUMO

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.


Assuntos
Exposição Ocupacional , Saúde Ocupacional , Humanos , Vibração/efeitos adversos , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/análise , Veículos Automotores , Ergonomia
3.
Work ; 71(1): 235-247, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34924417

RESUMO

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.


Assuntos
Dor Lombar , Doenças Musculoesqueléticas , Doenças Profissionais , Exposição Ocupacional , Idoso , Estudos de Casos e Controles , Humanos , Ferro , Dor Lombar/epidemiologia , Dor Lombar/etiologia , Doenças Musculoesqueléticas/epidemiologia , Doenças Musculoesqueléticas/etiologia , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Vibração/efeitos adversos
4.
ACS Omega ; 6(39): 25381-25388, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34632196

RESUMO

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.

5.
Eur J Orthop Surg Traumatol ; 30(3): 411-417, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31650335

RESUMO

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.


Assuntos
Reconstrução do Ligamento Cruzado Anterior/métodos , Fêmur/cirurgia , Adulto , Ligamento Cruzado Anterior/diagnóstico por imagem , Ligamento Cruzado Anterior/cirurgia , Lesões do Ligamento Cruzado Anterior/diagnóstico por imagem , Lesões do Ligamento Cruzado Anterior/reabilitação , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/reabilitação , Fêmur/diagnóstico por imagem , Humanos , Masculino , Dispositivos de Fixação Ortopédica , Estudos Prospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
6.
ACS Appl Mater Interfaces ; 8(19): 11954-68, 2016 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-27108739

RESUMO

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.


Assuntos
Proliferação de Células/efeitos dos fármacos , Grafite , Células-Tronco Mesenquimais/metabolismo , Nanocompostos/química , Osteoblastos/metabolismo , Polietileno , Soroalbumina Bovina/química , Animais , Bovinos , Linhagem Celular , Grafite/química , Grafite/farmacologia , Humanos , Células-Tronco Mesenquimais/citologia , Camundongos , Osteoblastos/citologia , Polietileno/química , Polietileno/farmacologia
7.
Reprod Sci ; 20(10): 1162-74, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23427177

RESUMO

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.


Assuntos
Actinas/metabolismo , Citoesqueleto/metabolismo , Estrogênios/farmacologia , Proteínas de Membrana/metabolismo , Espermátides/metabolismo , Testículo/metabolismo , Animais , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/patologia , Endocitose/efeitos dos fármacos , Endocitose/fisiologia , Estrogênios/toxicidade , Masculino , Ratos , Ratos Sprague-Dawley , Espermátides/efeitos dos fármacos , Espermátides/patologia , Testículo/efeitos dos fármacos , Testículo/patologia
8.
Biochim Biophys Acta ; 1834(1): 8-15, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23072795

RESUMO

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.


Assuntos
Endométrio/metabolismo , Genitália Masculina/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Reprodução/fisiologia , Animais , Feminino , Humanos , Infertilidade/metabolismo , Infertilidade/fisiopatologia , Masculino
9.
Histochem Cell Biol ; 136(5): 543-55, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21915674

RESUMO

Vimentin, type III intermediate filament, has stage-specific localization in the Sertoli cell. In the rat, during stages I-V and XI-XIV of the seminiferous epithelium, vimentin is localized in the perinuclear area with filaments projecting into the apical region toward the developing germ cells. These filaments decrease in length at stages VI-VII with perinuclear staining in stages VIII-IX, when spermiation occurs. Our earlier studies following 17ß-estradiol treatment to adult male rats demonstrated an increase in germ cell apoptosis, spermiation failure and disruption of Sertoli cell microfilaments and microtubules. The present study was undertaken to determine the stage-specific distribution of vimentin and its involvement in spermiation failure and germ cell apoptosis. Immunofluorescence studies revealed that in contrast to the perinuclear localization with small extensions in control stages VII-IX, long extensions radiating apically to the spermatids in deep recess were observed in the treated group. Immunoprecipitation studies showed marked absence of phosphorylated vimentin in stages VII-VIII in the treated group. Further, localization of plectin, cytoskeletal linker protein, showed decrease in all the stages of spermatogenesis following estradiol treatment. Interestingly, for the first time the localization of plectin in the tubulobulbar complex was observed. In conclusion, the study suggests that estradiol treatment leads to an effect on vimentin phosphorylation, which could have inhibited the disassembly of vimentin leading to retention of apical projection in stages VII-VIII. These effects could be presumably due to a decrease in plectin, affecting the reorganization of vimentin and therefore the apical movement of spermatids, leading to spermiation failure.


Assuntos
Estradiol/farmacologia , Estrogênios/farmacologia , Epitélio Seminífero/efeitos dos fármacos , Células de Sertoli/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Vimentina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , AMP Cíclico/metabolismo , Imunofluorescência , Masculino , Microscopia Confocal , Fosforilação/efeitos dos fármacos , Plectina/metabolismo , Ratos , Ratos Sprague-Dawley , Epitélio Seminífero/metabolismo , Epitélio Seminífero/patologia , Células de Sertoli/metabolismo , Células de Sertoli/patologia , Espermátides/efeitos dos fármacos , Espermátides/metabolismo , Espermátides/patologia
10.
Endocrinology ; 150(4): 1861-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19095743

RESUMO

Spermiation is the final phase of spermatogenesis leading to release of mature spermatids into the lumen of the seminiferous tubules. Morphologically, it involves a series of events, namely removal of excess spermatid cytoplasm, removal of ectoplasmic specialization, formation of tubulobulbar complex, and final disengagement of the spermatid from the Sertoli cell. Previous studies in our laboratory have shown that administration of 17beta-estradiol at a dose of 100 microg/kg body weight for 10 d resulted in failure of spermiation. This was accompanied by a suppression of FSH and intratesticular testosterone with a concomitant rise in intratesticular 17beta-estradiol. The present study was undertaken to determine the cause of failure and subsequently the molecular events in spermiation. Electron microscopic and confocal studies revealed an absence of tubulobulbar complex in step 19 spermatids after estradiol treatment, highlighting the significance of these structures in spermiation. It was further observed that treatment affected the Sertoli cell cytoskeleton and Arp2/3 complex that is critical for de novo polymerization of actin during tubulobulbar complex formation. In conclusion, the present study reports the role of 17beta-estradiol in inhibiting the formation of tubulobulbar complex, which could be one of the mechanism by which environmental estrogens influence male fertility.


Assuntos
Estradiol/farmacologia , Espermatogênese/efeitos dos fármacos , Proteína 3 Relacionada a Actina/metabolismo , Animais , Western Blotting , Imunofluorescência , Imuno-Histoquímica , Integrina alfa6beta1/metabolismo , Masculino , Microscopia , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Reação em Cadeia da Polimerase , Ratos , Espermátides/efeitos dos fármacos , Espermátides/metabolismo , Espermátides/ultraestrutura , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testículo/ultraestrutura , Vinculina/metabolismo
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