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INTRODUCTION: Whole genome sequencing (WGS) was introduced into Swiss antimicrobial resistance monitoring in 2022 as an additional method to phenotypic antimicrobial susceptibility testing by broth microdilution to characterize presumptive third-generation cephalosporin-resistant (3GC-R) Escherichia coli. Caecal samples from Swiss slaughter calves and fattening pigs, as well as beef and pork meat from Swiss retail taken in 2021, were analyzed for the presence of 3GC-R E. coli according to European harmonized protocols. In 2021, 3GC-R E. coli was detected in 23,8 % of slaughter calves, 5,9 % of fattening pigs, and 0 % of meat. Comparative analysis of the antimicrobial resistance results obtained by phenotypic measurement and those obtained by the detection of corresponding underlying molecular mechanisms by WGS showed very high agreement (99 %). Resistance to third-generation cephalosporins (3GCs) was mainly associated with the presence of blaCTX-M-15 in E. coli isolates from calves and blaCTX-M-1 in E. coli isolates from pigs and mutations in the ampC-promoter (g.-42 C>T) in E. coli isolates from both animal species. Moreover, WGS data were used for phylogenetic analysis based on multi locus sequence types (MLST) and core genome MLST(cgMLST) revealing that 3GC-R E. coli isolated from Swiss slaughter calves and fattening pigs were genetically diverse. In this study, it was shown that using WGS alone to monitor antimicrobial resistance could detect trends in known molecular antimicrobial resistance mechanisms while also providing other valuable information about the isolates, such as genetic relatedness. However, only by combining phenotypic susceptibility testing and WGS early detection of previously unknown resistance mechanisms will be possible.
INTRODUCTION: Le séquençage du génome entier (Whole Genome Sequencing, WGS) a été introduit dans la surveillance suisse de la résistance aux antibiotiques en 2022 en tant que méthode supplémentaire aux tests phénotypiques de sensibilité aux antibiotiques pour caractériser les Escherichia coli résistants aux céphalosporines de troisième génération (3GC-R). Des échantillons de cæcum pris en 2021 à l'abattoir de veaux et de porcs suisses, ainsi que de viande de bÅuf et de porc provenant de détaillants suisses ont été analysés pour détecter la présence d'E. coli 3GC-R conformément aux protocoles européens harmonisés. En 2021, les E. coli 3GC-R ont été détectés dans 23,8 % des veaux d'abattage, 5,9 % des porcs d'engraissement et 0 % dans la viande. Les résultats de résistance aux antibiotiques obtenus par mesure phénotypique et ceux obtenus par la détection des mécanismes moléculaires sous-jacents concordaient à 99 %. La résistance aux céphalosporines de troisième génération était principalement associée à la pré-sence de blaCTX-M-15 dans les isolats d'E. coli provenant de veaux et de blaCTX-M-1 dans les isolats d'E. coli provenant de porcs et à des mutations dans le promoteur ampC (g.-42 C>T) dans les isolats d'E. coli provenant des deux espèces animales. Les données WGS ont également été utilisées pour une analyse phylogénétique basée sur les types de séquences multilocus (MLST) et MLST du génome de base (cgMLST) révélant que les E. coli 3GC-R isolés des veaux et des porcs suisses étaient génétiquement divers. Dans cette étude, il a été démontré que l'utilisation du WGS seul pour surveiller la résistance aux antibiotiques pouvait détecter des tendances dans les mécanismes moléculaires connus de la résistance aux antibiotiques tout en fournissant d'autres informations précieuses sur les isolats, comme la parenté génétique. Cependant, ce n'est qu'en combinant les tests de sensibilité phénotypique avec le WGS que la détection pré-coce de mécanismes de résistance inconnus sera possible.
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Doenças dos Bovinos , Infecções por Escherichia coli , Doenças dos Suínos , Animais , Bovinos , Suínos , Escherichia coli/genética , Antibacterianos/farmacologia , Suíça , Projetos Piloto , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/veterinária , Tipagem de Sequências Multilocus/veterinária , Filogenia , beta-Lactamases/genética , Farmacorresistência Bacteriana/genética , Sequenciamento Completo do Genoma/veterinária , Cefalosporinas/farmacologiaRESUMO
BACKGROUND: Smoking remains one of the leading preventable causes of death. Smoking leaves a strong signature on the blood methylome as shown in multiple studies using the Infinium HumanMethylation450 BeadChip. Here, we explore novel blood methylation smoking signals on the Illumina MethylationEPIC BeadChip (EPIC) array, which also targets novel CpG-sites in enhancers. METHOD: A smoking-methylation meta-analysis was carried out using EPIC DNA methylation profiles in 1407 blood samples from four UK population-based cohorts, including the MRC National Survey for Health and Development (NSHD) or 1946 British birth cohort, the National Child Development Study (NCDS) or 1958 birth cohort, the 1970 British Cohort Study (BCS70), and the TwinsUK cohort (TwinsUK). The overall discovery sample included 269 current, 497 former, and 643 never smokers. Replication was pursued in 3425 trans-ethnic samples, including 2325 American Indian individuals participating in the Strong Heart Study (SHS) in 1989-1991 and 1100 African-American participants in the Genetic Epidemiology Network of Arteriopathy Study (GENOA). RESULTS: Altogether 952 CpG-sites in 500 genes were differentially methylated between smokers and never smokers after Bonferroni correction. There were 526 novel smoking-associated CpG-sites only profiled by the EPIC array, of which 486 (92%) replicated in a meta-analysis of the American Indian and African-American samples. Novel CpG sites mapped both to genes containing previously identified smoking-methylation signals and to 80 novel genes not previously linked to smoking, with the strongest novel signal in SLAMF7. Comparison of former versus never smokers identified that 37 of these sites were persistently differentially methylated after cessation, where 16 represented novel signals only profiled by the EPIC array. We observed a depletion of smoking-associated signals in CpG islands and an enrichment in enhancer regions, consistent with previous results. CONCLUSION: This study identified novel smoking-associated signals as possible biomarkers of exposure to smoking and may help improve our understanding of smoking-related disease risk.
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Estudo de Associação Genômica Ampla/métodos , Família de Moléculas de Sinalização da Ativação Linfocitária/genética , Fumar Tabaco/sangue , Fumar Tabaco/genética , Negro ou Afro-Americano/genética , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Ilhas de CpG , Metilação de DNA , Exposição Ambiental/efeitos adversos , Epigênese Genética , Epigenoma , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumantes/estatística & dados numéricos , Fumar Tabaco/etnologia , Reino Unido/epidemiologia , População Branca/genética , Indígena Americano ou Nativo do Alasca/genéticaRESUMO
Embryo biopsy for fetal sexing has clinical application, but few reports are available of its use within an active embryo transfer program. We evaluated results on biopsy of 459 embryos over one breeding season. There were no significant differences in pregnancy rate between biopsied and non-biopsied embryos (72% vs 73%) or for biopsied embryos recovered at the centre (73%) compared with those shipped overnight (72%). However, the pregnancy rate decreased significantly in shipped embryos biopsied ≥20h after collection. Overall, 86% of biopsies provided a sex diagnosis. The likelihood of a positive genomic (g) DNA result was significantly higher for biopsies from large blastocysts (96%) than from smaller embryos (70-85%). In total, 38% of biopsies were positive for Y chromosome DNA (Y-DNA) and were diagnosed as male. Subsequently, 95% of Y-DNA-positive embryos were confirmed as male and 78% of Y-DNA-negative embryos were confirmed as female. The accuracy of prediction of female (Y-DNA negative) was significantly higher when the biopsy sample was probed for Y-DNA only compared with probing for both gDNA and Y-DNA. We estimate that by transferring only Y-DNA-negative embryos, 3% of potential female pregnancies may have been lost, and production of male pregnancies was reduced by 72%.
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Blastocisto/patologia , Embrião de Mamíferos/patologia , Cavalos/embriologia , Reação em Cadeia da Polimerase , Diagnóstico Pré-Implantação , Análise para Determinação do Sexo , Animais , Argentina , Biópsia , Cruzamento/economia , Cruzamento/métodos , Comércio , Transferência Embrionária/economia , Transferência Embrionária/métodos , Transferência Embrionária/veterinária , Feminino , Masculino , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/veterinária , Gravidez , Diagnóstico Pré-Implantação/métodos , Diagnóstico Pré-Implantação/veterinária , Análise para Determinação do Sexo/métodos , Análise para Determinação do Sexo/veterinária , Medicina Veterinária Esportiva/economia , Medicina Veterinária Esportiva/métodos , Medicina Veterinária Esportiva/organização & administraçãoRESUMO
AIM: To evaluate the learning of basic life support (BLS) measures on the part of laypersons after 3different teaching programs. DESIGN: A quasi-experimental before-after study involving a non-probabilistic sample without a control group was carried out. SCOPE: Primary school teacher students from the University of Santiago (Spain). PARTICIPANTS: A total of 124 students (68.8% women and 31.2% men) aged 20-39 years (M=22.23; SD=3.79), with no previous knowledge of BLS, were studied. INTERVENTIONS: Three teaching programs were used: a traditional course, an audio-visual approach and feedback devices. MAIN VARIABLES OF INTEREST: Chest compressions as sole cardiopulmonary resuscitation skill evaluation: average compression depth, compression rate, chest recoil percentage and percentage of correct compressions. Automated external defibrillator: time needed to apply a shock before and after the course. RESULTS: There were significant differences in the results obtained after 2minutes of chest compressions, depending on the training program received, with feedback devices having a clear advantage referred to average compression depth (p<0.001), compression rate (p<0.001), chest recoil percentage (p<0.001) and percentage of correct compressions (p<0.001). Regarding automated external defibrillator, statistically significant differences were found in Tafter (p=0.025). CONCLUSIONS: The teaching course using feedback devices obtained the best results in terms of the quality of chest compressions, followed by the traditional course and audio-visual approach. These favorable results were present in both men and women. All 3teaching methods reached the goal of reducing defibrillation time.
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Reanimação Cardiopulmonar/educação , Professores Escolares , Ensino , Adulto , Recursos Audiovisuais , Reanimação Cardiopulmonar/métodos , Oscilação da Parede Torácica , Desfibriladores , Cardioversão Elétrica , Feminino , Feedback Formativo , Humanos , Masculino , Manequins , Parada Cardíaca Extra-Hospitalar/epidemiologia , Parada Cardíaca Extra-Hospitalar/terapia , Fatores Socioeconômicos , Espanha , Ensino/educação , Fatores de Tempo , Adulto JovemRESUMO
PURPOSE: To determine the cost reduction and complication rates of using an enhanced recovery pathway (Fast-track) when compared to traditional recovery in primary total hip replacement (THR) and total knee replacement (TKR), as well as to determine if there were significant differences in complication rates. MATERIAL AND METHODS: Retrospective review of 100 primary total arthroplasties using the Fast-track recovery system and another 100 using conventional recovery. Gender, Charlston comorbidity index, ASA score, length of stay and early complications were measured, as well in-hospital complications and those in the first six months, re-admissions and transfusion rates. The total and daily cost of stay was determined and the cost reduction was calculated based on the reduction in the length of stay found between the groups. RESULTS: Both groups where comparable as regards age, gender, ASA score, and Charlston index. The mean reduction in length of stay was 4.5 days for TKR and 2.1 days for THR. The calculated cost reduction was 1266 euros for TKR and 583 euros for THR. There were no statistically significant differences between groups regarding in-hospital complications, transfusion requirements, re-admissions and complication rates in the first six months. DISCUSSION: There are few publications in the literature reviewed that analyse the cost implications of using fast-track recovery protocols in arthroplasty. Several published series comparing recovery protocols found no significant differences in complication rates either. The use of a fast-track recovery protocol resulted in a significant cost reduction of 1266 euros for the TKR group and 583 for the THR group, without affecting complication rates.
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Artroplastia de Quadril , Artroplastia do Joelho , Custos Hospitalares/estatística & dados numéricos , Assistência Perioperatória/métodos , Complicações Pós-Operatórias/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/economia , Artroplastia do Joelho/economia , Feminino , Seguimentos , Humanos , Tempo de Internação/economia , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória/economia , Complicações Pós-Operatórias/economia , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Espanha , Resultado do TratamentoRESUMO
The non-invasive leaf patch clamp pressure (LPCP) probe measures the attenuated pressure of a leaf patch, P(p) , in response to an externally applied magnetic force. P(p) is inversely coupled with leaf turgor pressure, P(c) , i.e. at high P(c) values the P(p) values are small and at low P(c) values the P(p) values are high. This relationship between P(c) and P(p) could also be verified for 2-m tall olive trees under laboratory conditions using the cell turgor pressure probe. When the laboratory plants were subjected to severe water stress (P(c) dropped below ca. 50 kPa), P(p) curves show reverse diurnal changes, i.e. during the light regime (high transpiration) a minimum P(p) value, and during darkness a peak P(p) value is recorded. This reversal of the P(p) curves was completely reversible. Upon watering, the original diurnal P(p) changes were re-established within 2-3 days. Olive trees in the field showed a similar turnover of the shape of the P(p) curves upon drought, despite pronounced fluctuations in microclimate. The reversal of the P(p) curves is most likely due to accumulation of air in the leaves. This assumption was supported with cross-sections through leaves subjected to prolonged drought. In contrast to well-watered leaves, microscopic inspection of leaves exhibiting inverse diurnal P(p) curves revealed large air-filled areas in parenchyma tissue. Significantly larger amounts of air could also be extracted from water-stressed leaves than from well-watered leaves using the cell turgor pressure probe. Furthermore, theoretical analysis of the experimental P(p) curves shows that the propagation of pressure through the nearly turgorless leaf must be exclusively dictated by air. Equations are derived that provide valuable information about the water status of olive leaves close to zero P(c) .
Assuntos
Olea/fisiologia , Folhas de Planta/fisiologia , Água/fisiologia , Desidratação , Luz , Técnicas de Patch-Clamp , Transpiração Vegetal , PressãoRESUMO
We quantified parameters for a model of leaf-level photosynthesis for olive, and tested the model against an independent dataset. Specific temperature-dependence parameters of the model for olive leaves were measured, as well as the relationship of the model parameters with area-based leaf nitrogen (N) content. The effect of soil water deficit on leaf photosynthesis was examined by applying two irrigation treatments to 29-year-old trees growing in a plantation: drip irrigation sufficient to meet the crop water requirements (I) and dry-farming (D). In both treatments, leaves had a higher photosynthetic capacity in April than in August. In August, photosynthetic capacity was lower in D trees than in I trees. Leaf photosynthetic capacity was linearly and positively related to leaf N content on an area basis (N(a)) and to leaf mass per unit area (LMA), and the regression slope varied with irrigation treatment. The seasonal reduction in N(a) was used in the model to predict photosynthesis under drought conditions. Olive leaves showed a clear limitation of photosynthesis by triose phosphate utilization (TPU) even at 40 degrees C, and the data suggest that olive invests fewer resources in TPU than other species. The seasonal decrease in photosynthetic capacity moderated the stomatal limitation to carbon dioxide (CO(2)) fixation as soil water deficit increased. Further, it enabled leaves to operate close to the transition point between photosynthetic limitation due to RuBP carboxylation capacity and that due to RuBP regeneration capacity, and resulted in a near constant value of internal CO(2) concentration from April to August. Under well watered conditions, N-use efficiency of the olive leaves was enhanced at the expense of reduced water-use efficiency.
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Desastres , Olea/fisiologia , Fotossíntese , Folhas de Planta/fisiologia , Clima , Cinética , Modelos Biológicos , Nitrogênio/análise , Chuva , Espanha , TemperaturaRESUMO
Effectiveness of conventional cytotoxic treatment of rhabdomyosarcoma (RMS) may be limited by the development of multidrug resistance (MDR) mediated by mdr1 gene. This gene codes for P-glycoprotein (P-gp) which has been related to a immunoregulatory function. Modulation of HLA expression by P-gp has been described in different types of tumor cells including RMS. However, very little is known about biological implications of the P-gp expression in RMS patients treated with conventional chemotherapy. In order to study the problem, we used embryonal RMS tissue samples from treated patients. Our results indicated that positive RMS samples to mdr1 show higher HLA class I expression than those which were negative to mdr1 PCR, what indicates a significant correlation between the expression of both molecules. In addition, we developed two resistant RMS cell lines (A-204-1 and 2) using similar concentrations of actinomycin D as are plasma levels in clinical situation. Both resistant cell lines showed mdr1 expression and an increase of HLA class I expression which was dose-dependent. These results demonstrated that conventional chemotherapy of embryonal RMS is able to induce resistance which can modulate HLA class I expression and suggest that immunological studies of these tumors may be necessary to the design new specific therapeutic strategies.
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Resistencia a Medicamentos Antineoplásicos , Antígenos de Histocompatibilidade Classe I/análise , Rabdomiossarcoma Embrionário/tratamento farmacológico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/análise , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Humanos , RNA Mensageiro/análise , Rabdomiossarcoma Embrionário/imunologiaRESUMO
The compensation heat pulse method is widely used to estimate sap flow in conducting organs of woody plants. Being an invasive technique, calibration is crucial to derive correction factors for accurately estimating the sap flow value from the measured heat pulse velocity. We compared the results of excision and perfusion calibration experiments made with mature olive (Olea europaea L. 'Manzanilla de Sevilla'), plum (Prunus domestica L. 'Songal') and orange (Citrus sinensis (L.) Osbeck. 'Cadenero') trees. The calibration experiments were designed according to current knowledge on the application of the technique and the analysis of measured heat pulse velocities. Data on xylem characteristics were obtained from the experimental trees and related to the results of the calibration experiments. The most accurate sap flow values were obtained by assuming a wound width of 2.0 mm for olive and 2.4 mm for plum and orange. Although the three possible methods of integrating the sap velocity profiles produced similar results for all three species, the best results were obtained by calculating sap flow as the weighted sum of the product of sap velocity and the associated sapwood area across the four sensors of the heat-pulse-velocity probes. Anatomical observations showed that the xylem of the studied species can be considered thermally homogeneous. Vessel lumen diameter in orange trees was about twice that in the olive and plum, but vessel density was less than half. Total vessel lumen area per transverse section of xylem tissue was greater in plum than in the other species. These and other anatomical and hydraulic differences may account for the different calibration results obtained for each species.
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Transporte Biológico , Citrus sinensis/fisiologia , Olea/fisiologia , Prunus/fisiologia , Xilema/anatomia & histologia , Fenômenos Biomecânicos/métodos , Calibragem , Citrus sinensis/anatomia & histologia , Olea/anatomia & histologia , Perfusão/métodos , Folhas de Planta/metabolismo , Prunus/anatomia & histologia , Água/metabolismo , Xilema/fisiologiaAssuntos
Hemangioma Cavernoso/patologia , Osso Occipital/patologia , Osso Parietal/patologia , Neoplasias Cranianas/patologia , Feminino , Hemangioma Cavernoso/complicações , Hemangioma Cavernoso/epidemiologia , Humanos , Pessoa de Meia-Idade , Osteólise/etiologia , Estudos Retrospectivos , Neoplasias Cranianas/complicações , Neoplasias Cranianas/epidemiologiaRESUMO
Poor balance is one of the most common risk factors for falling, a common cause of work-related injury and death. To evaluate the effects of a 10-week intervention program on balance in older adults, 12 participants aged 61-77 years (age = 70.4 +/- 5.4 years; mean +/- SD) completed an exercise program (60 min, 2 days.week-1 for 10 weeks) performed while laying/sitting on large air-filled exercise balls (Thera-Band). Several postural sway composite scores (determined while standing with feet apart and semitandem, eyes open and closed) improved (p < or = 0.05) including medial-lateral amplitude and speed of sway (reduced by approximately 9%), and instantaneous speed (reduced by approximately 13%). Reductions in XY area approached (p = 0.06) statistical significance and anterior-posterior amplitude and speed of sway did not change. Functional reach also improved (20.3%). These results suggest that challenging the physiological systems involved in balance control while on the nonstable support surface of the exercise balls improves both static and dynamic balance in older adults and may reduce the risk for falling.
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Acidentes por Quedas/prevenção & controle , Acidentes de Trabalho/prevenção & controle , Educação Física e Treinamento/métodos , Equilíbrio Postural , Postura , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The suitability of introducing molecular interference effects into coherent scattering phenomenology is considered here in the case of X and gamma photon transport in biological tissues. In order to make its implementation practicable in most of the existing open user Monte Carlo codes, a self-consistent basic set of tabulations for the linear differential scattering coefficient was proposed. The tabulations were critically reviewed by testing their validity over the entire range of the momentum transfer variable from 0 to 10(10) nm(-1). Implementation in three different Monte Carlo codes was performed, and they proved to be reliable.
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Modelos Biológicos , Método de Monte Carlo , Fótons , Espalhamento de Radiação , Tecido Adiposo/anatomia & histologia , Tecido Adiposo/metabolismo , Osso e Ossos/anatomia & histologia , Osso e Ossos/metabolismo , Colágeno/metabolismo , Simulação por Computador , Humanos , Minerais/metabolismo , Imagens de Fantasmas , Reprodutibilidade dos Testes , Água/metabolismoRESUMO
Human CD38 is a 45 kD ectoenzyme endowed with ADP-ribosyl cyclase and hydrolase activities. The molecule plays a central role in lymphocyte activation, proliferation and selectin-type adhesion with endothelial cells (HEC). A HEC surface molecule displaying all the features of a CD38L has been identified by means of a mAb (Moon-1), able to block CD38-mediated adhesion processes. The 130 kD molecule recognized by Moon-1 is CD31, a member of the Ig superfamily. This paper reports on the analysis of the surface expression of CD38 and CD38L in various human tissues of adult origin and compared in some instances to the fetal (9-14 weeks) counterparts. This was achieved by means of immunohistochemical techniques and analysis of purified cell populations. Among the specimens analyzed, CD38 is expressed by a vast array of cells of lymphatic origin as well as by the skeletal and cardiac muscle fibers, the bronchi (epithelial cells), the parotid gland (ductal epithelial cells) and hepatic sinusoids. On the contrary, CD31 proved constantly expressed by HEC at high levels, independent of the organ or tissue analyzed or of the kind of vessel. Other cells expressing CD38L were found in the lymphoid compartment (follicle mantle B cells and plasma cells), in the lungs (alveolar ducts, alveoli and lymphatic vessels) and in the kidney (glomerular cells). Interestingly, no fetal organ or tissue ever expressed CD38 and its ligand. The above results were enriched by the analysis of the expression of the two molecules on purified populations including mononuclear cells from the lamina propria of the gastro-intestinal tract and broncho-alveolar lavage lymphocytes.
Assuntos
Antígenos CD , Antígenos de Diferenciação/metabolismo , NAD+ Nucleosidase/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Antígenos de Diferenciação/análise , Brônquios/imunologia , Brônquios/metabolismo , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Sistema Digestório/imunologia , Sistema Digestório/metabolismo , Feminino , Feto/imunologia , Feto/metabolismo , Humanos , Imuno-Histoquímica , Rim/imunologia , Rim/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Tecido Linfoide/imunologia , Tecido Linfoide/metabolismo , Glicoproteínas de Membrana , Monócitos/imunologia , Músculo Esquelético/imunologia , Músculo Esquelético/metabolismo , Miocárdio/imunologia , Miocárdio/metabolismo , NAD+ Nucleosidase/análise , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Gravidez , Pele/imunologia , Pele/metabolismo , Distribuição TecidualRESUMO
A human tumor cell line designated RMS-GR was established from an embryonal rhabdomyosarcoma. The monolayer cells were polygonal, round or spindle-shaped. The RMS-GR cell line became stable with a doubling time of 42 h. Tumorigenicity of the cells was confirmed by heterotransplantion into nude mice. Electron microscopic images showed typical cytoplasmic inclusion of aggregated intermediate filaments and myofibril-like thin filaments. The expression of desmin, vimentin, actin and human myoglobin was recognized by cytofluorometric analyses, and a large fraction of CK-MM and small fractions of CK-BB and MCK-1 isoenzymes were found. Chromosomal analysis showed that the modal chromosome number was consistently near triploid with structural abnormalities mostly involving chromosomes 1, 3 and 8, and additional unidentified markers. No alteration of chromosome 2 was observed. The RMS-GR cell line may provide a system to identify genes which are involved in the pathogenic mechanism of rhabdomyosarcomas, and to investigate the modulation of myogenic differentiation.
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Rabdomiossarcoma Embrionário/patologia , Células Tumorais Cultivadas , Actinas/análise , Animais , Divisão Celular , Aberrações Cromossômicas , Creatina Quinase/análise , Humanos , Isoenzimas , Queratinas/análise , Camundongos , Camundongos Nus , Mioglobina/análise , Transplante de Neoplasias , Rabdomiossarcoma Embrionário/química , Rabdomiossarcoma Embrionário/genética , Transplante Heterólogo , Vimentina/análiseRESUMO
Human embryonal cell line RD is derived from rhabdomyosarcoma, a tumor of childhood that arises from rhabdomyoblasts probably arrested somewhere along their pathway to maturation. Because actinomycin D is a drug of choice in the treatment of rhabdomyosarcomas, and because it has been used to induce differentiation as an alternative therapy for myeloproliferative syndromes, we treated RD cells with different concentrations of actinomycin D and evaluated the effects on growth and differentiation. Actinomycin D treatment in vitro caused time- and dose-dependent growth inhibition. Interestingly, RD cells treated with low doses (2.85 and 5.7 nmol/L) of actinomycin D for 6 days showed morphologic and phenotypic differentiation, with increased expression of desmin, alpha-actinin, and tropomyosin. However, treatment with 11.4 nmol/L actinomycin D strongly inhibited growth and had cytotoxic effects that prevented the cells from attaining myogenic differentiation. We conclude that exposure of this human embryonal rhabdomyosarcoma cell line to low concentrations of actinomycin D released the neoplastic cells from their blockade, allowing them to recover normal myogenic development. We suggest a potential role for differentiation therapy in the treatment of rhabdomyosarcomas.
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Antibióticos Antineoplásicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Dactinomicina/farmacologia , Rabdomiossarcoma/patologia , Contagem de Células/efeitos dos fármacos , Proteínas Contráteis/metabolismo , Proteínas Contráteis/ultraestrutura , Citometria de Fluxo , Humanos , Filamentos Intermediários/metabolismo , Filamentos Intermediários/ultraestrutura , Microscopia Eletrônica , Rabdomiossarcoma/tratamento farmacológico , Rabdomiossarcoma/ultraestrutura , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/patologia , Células Tumorais Cultivadas/ultraestruturaRESUMO
The term CTD has been used to refer to those musculoskeletal impairments that appear to be work-related and tend to be chronic. Upper extremity CTD are categorized in three major groups: tendon disorders, neurovascular disorders, and nerve. Kienböck's disease, on the other hand, has been documented in the workplace and has a similar etiology, but due to current anatomic classifications cannot be considered a CTD. With this in mind, the present article reviews risk factors, diagnosis, and treatment, with the purpose of providing physicians, engineers, and designers with information to reduce the risk of workers developing this potentially debilitating disease. Furthermore, additional support will be accumulated and combined with Part I of this article with the intent of introducing into the literature a new category of upper extremity CTD: Bone Disorders.
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Osteocondrite/diagnóstico , Osteocondrite/etiologia , Ergonomia , Humanos , Doenças Profissionais/diagnóstico , Doenças Profissionais/etiologia , Doenças Profissionais/reabilitação , Osteocondrite/reabilitação , Postura , Fatores de RiscoRESUMO
Cumulative trauma disorders (CTD) pose a major industrial problem in terms of increased medical costs, lost productivity and degraded worker health and safety. From an anatomical view, CTD's are classified into three major categories: tendon disorders, neurovascular disorders and nerve disorders. Up until recently these categories seemed to cover CTD of the upper extremity, however, Kienböck's disease, a typically less common disease and one that does not fit into the established CTD categories, has been observed to exhibit CTD characteristics and does appear in the manufacturing environment. The most common types of employment observed to exhibit individuals with this disease are carpentry, jobs involving the use of pneumatic tools (wrench), spot welders, sheet metal work, farmers and factory workers. The present article makes a critical examination of the relevant anatomy and etiologic aspects of this disease.
Assuntos
Transtornos Traumáticos Cumulativos/etiologia , Doenças Profissionais/etiologia , Osteocondrite/etiologia , Punho/patologia , Humanos , Punho/anatomia & histologiaRESUMO
This paper examines the effect of various arm postures on peak pinch strength. Twenty (20) able-bodied, male subjects volunteered to participate in a set of two experiments. The first experiment examined the effect of shoulder and elbow posture on peak pinch strength. The second experiment examined the effect of forearm posture, wrist posture, and pinch type on peak pinch strength. Results from the first experiment indicated that elbow posture had a significant effect on pinch strength. It was documented that extreme elbow flexion decreased pinch strength by up to 9%. Results from the second experiment indicated that deviated wrist postures, forearm postures, and pinch type significantly decreased pinch strength as much as 33%. Ergonomic guidelines which utilize the above factors as significant modifiers of pinch strength capacity may assist ergonomists to reduce the risk of injury and development of cumulative trauma disorders in the workplace.
Assuntos
Braço , Ergonomia , Contração Muscular/fisiologia , Postura/fisiologia , Punho , Adulto , Análise de Variância , Fenômenos Biomecânicos , Transtornos Traumáticos Cumulativos/prevenção & controle , Humanos , MasculinoRESUMO
Gene transfection has been accomplished with a variety of techniques such as DEAE dextran, calcium phosphate coprecipitation, protoplast fusion, liposomes, microinjection and recombinant bacteriophages. However, transfection by electroporation, consisting of the reversible permeabilization of cell membranes after exposure to a pulsed electric field, has been shown to be the most rapid, simple and efficient method for the stable incorporation of genes in different cell lines. We studied rhabdomyosarcoma cells subjected to electroporation in two different vol. [400 microliters (group 1) and 150 microliters (group 2] of 140 mM NaCl/15 mM Hepes buffer, pH 7.2) and evaluated the effects of electroporation volume on growth and differentiation. Low sample volumes induced a terminal process of morphological and ultrastructural myogenic differentiation in rhabdomyosarcoma cells, which concluded with cell death. Our results suggest that in electroporation low sample vol. of rhabdomyosarcoma cells induced morphological and phenotypic differentiation, with increased expression of desmin, alpha-actinin and tropomyosin.