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On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy dependence of the speed of light in vacuo for photons as predicted by several quantum gravity models. Based on a set of assumptions on the possible intrinsic spectral and temporal evolution, we obtain competitive lower limits on the quadratic leading order of speed of light modification.
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OBJECTIVES: To examine the relationship between disease activity and vaspin, neutrophil gelatinase-associated lipocalin (NGAL) and apolipoprotein levels in patients with psoriatic arthritis (PsA). BACKGROUND: Psoriatic arthritis (PsA) is a chronic inflammatory arthritis, which is related with psoriasis. Adipokines are the mediators which play a role in metabolic homeostasis and inflammatory conditions. METHODS: The levels of vaspin, NGAL, apolipoproteins and their correlations with disease activity were compared in 50 psoriatic arthritis patients and 36 healthy controls. RESULTS: The levels of vaspin, NGAL and apolipoprotein B/A1 ratio were significantly higher in the patient group (p 0.05). CONCLUSION: This is the first study to have compared vaspin and NGAL levels in patients with PsA. Vaspin and NGAL can be used as a biomarker in PsA. Vaspin, NGAL and dyslipoproteinemia are not correlated with disease activity (Tab. 3, Ref. 63).
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Artrite Psoriásica , Lipocalina-2 , Serpinas , Proteínas de Fase Aguda , Apolipoproteínas/sangue , Artrite Psoriásica/sangue , Artrite Psoriásica/diagnóstico , Biomarcadores/sangue , Humanos , Lipocalina-2/sangue , Lipocalinas , Proteínas Proto-Oncogênicas , Serpinas/sangueRESUMO
OBJECTIVES: Restless legs syndrome (RLS) is a neurological disease with a chronic course that is characterised by sleep disorders and sensorimotor impairment. The aim of this study was to evaluate the prevalence and severity of RLS in psoriatic arthritis (PSA) patients and those with psoriasis (P). PATIENTS AND METHODS: The study included 50 patients with psoriasis (28 females, 22 males), 50 PSA patients (33 females, 17 males) and 50 healthy control subjects (34 females, 16 males), and all 3 groups were matched with respect to age, gender and body mass index (BMI). Evaluations were made using the International RLS Rating Scale, Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale, Insomnia Severity Index, Fatigue Severity Scale (FSS), Beck Depression Index (BDI) and the SF-36 quality of life scores. RESULTS: RLS was determined at a higher rate in the PSA patients (64.0%), compared to the P group (20.0%, pâ¯< 0.001) and the control group (14.0%, pâ¯< 0.001). The number of moderate and severe RLS cases was significantly higher in the PSA group (68.7%) compared to the P group (30%, pâ¯< 0.001) and the control group (0%, pâ¯< 0.001). In regression analysis, an independent correlation was found between the RLS score and PSQI (beta [ß]â¯= 0.269, pâ¯= 0.002), FSS (ßâ¯= 0.243, pâ¯= 0.003), SF-36 physical score (ßâ¯= 0.242, pâ¯= 0.004) and BDI (ßâ¯= 0.177, pâ¯= 0.036). CONCLUSION: RLS was determined in PSA patients at a higher rate than in psoriasis patients. The presence of RLS in PSA and psoriasis patients is related to impairments in sleep and quality of life, fatigue and depression.
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Artrite Psoriásica , Síndrome das Pernas Inquietas , Transtornos do Sono-Vigília , Artrite Psoriásica/complicações , Depressão , Fadiga , Feminino , Humanos , Masculino , Qualidade de Vida , Síndrome das Pernas Inquietas/complicações , Índice de Gravidade de Doença , Transtornos do Sono-Vigília/complicações , Inquéritos e QuestionáriosRESUMO
In recent years, drug delivery systems such as liposomes and microparticles have been used in clinic for the treatment of different diseases and from a regulatory point of view, a parenterally applied drug and drug delivery systems must be sterile and pyrogen free. Radiation sterilization is a method recognized by pharmacopoeias to achieve sterility criteria of parenterals. It has the ability to kill microorganisms in therapeutic products. The ability of, however, irradiation might also affect the performance of drug delivery systems. One of the most critical points is irradiation dose, because certain undesirable chemical and physical changes may accompany with the irradiation, especially with the traditionally applied dose of 25 kGy. Its ionizing property may cause fragmentation of covalent bond. The care must be paid to the applied dose. In this research, the effects of gamma irradiation on different drug delivery systems such as chitosan microparticles, liposomes, niosomes and sphingosomes were investigated. According to the experimental data, it can be concluded that gamma irradiation can be a suitable sterilization technique for liposome, niosome and sphingosome dispersions. When all irradiated drug carrier systems were taken into consideration, chitosan glutamate microparticles were found as the most radioresistant drug delivery system among the others.
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Sistemas de Liberação de Medicamentos , Quitosana , Raios gama , Humanos , Nanopartículas , EsterilizaçãoRESUMO
OBJECTIVES: Otitis media with effusion (OME) is the most common disease after viral infections of upper respiratory tract (URTI) in children. Studies indicate the important role of nitric oxide (NO) in the etiology of hearing loss. However, there is no study that focuses on the role of nitric oxide synthase (eNOS) polymorphisms in the cases with OME. The aim of the present study is to evaluate the eNOS polymorphisms in the pediatric patients with OME. MATERIALS AND METHODS: Eighty-nine patients who are diagnosed with otitis media with effusion and 85 healthy subjects who are compatible in terms of age and gender were included in the study. All patients in the study were subjected to complete ear, nose, throat (ENT) and audiological examinations. DNA analysis was performed with polymerase chain reaction (PCR) technique from the blood samples. The PCR product was cut by restriction fragment length polymorphism (RFLP) with BanII enzyme and checked by agarose gel electrophoresis. RESULTS: As a result of genetic analysis, there is no significant difference between patients and the controls in terms of eNOS Glu298Asp polymorphism (G/G, G/T, T/T). When these groups were compared in terms of allele distributions, a significant relationship was found between the patients and the controls (P=0.037). CONCLUSION: To the best of our knowledge, G allele was identified as predisposing to the development of OME and this is the first report indicates the correlation between the eNOS G894T polymorphism and OME in Turkey.
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Óxido Nítrico Sintase Tipo III/genética , Otite Média com Derrame/genética , Polimorfismo Genético , Alelos , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Reação em Cadeia da Polimerase , TurquiaRESUMO
INTRODUCTION: Carbon monoxide (CO) is a colorless, tasteless, odorless, nonirritant gas and CO poisoning affects all organ systems. AIM: We aimed to detect any possible effects of CO exposure on the argyrophilic nucleolar organizing region (AgNOR)-associated protein synthesis of heart cells and whether there is any relationship between AgNOR protein amount and both carboxyhemoglobin (COHb) level and histopathological evaluation methods used for the detection of damage in heart tissue after CO exposure. MATERIALS AND METHODS: The rats were divided into four groups (control, 1000, 3000, and 5000 ppm), each containing six rats. After CO intoxication, COHb levels were measured and the animals were killed on the 7th day. AgNOR staining was performed in the heart tissue. One hundred nuclei per rat were evaluated, and total AgNOR area/nuclear area and mean AgNOR number were analyzed for each nucleus. The CO exposure groups had significantly higher AgNOR values than the control group (p < 0.0001). According to cardiomyopathy (CMY) scoring methods, the differences between groups 3 and 4 and groups 1 and 2 were significant (p < 0.05). A significant positive correlation between AgNOR values and both CMY and COHb levels were detected. CONCLUSION: The detection of AgNOR protein amount may give information about the CMY levels and be used to detect the CO intoxication levels instead of COHb in later periods.
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Antígenos Nucleares/metabolismo , Intoxicação por Monóxido de Carbono/patologia , Miocárdio/patologia , Animais , Intoxicação por Monóxido de Carbono/sangue , Intoxicação por Monóxido de Carbono/metabolismo , Carboxihemoglobina/análise , Masculino , Miocárdio/metabolismo , Ratos WistarRESUMO
There is increasing evidence that cancers are heterogeneous and contain a hierarchical organization consisting of cancer stem cells and their differentiated cell progeny. These cancer stem cells are at the core of the tumor as they represent the clonogenic cells within a tumor. Moreover, these cells are considered to contain selective therapy resistance, which suggests a pivotal role in therapy resistance and tumor relapse. Here we show that differentiated cells can re-acquire stemness through factors secreted from fibroblasts. This induced CSC state also coincides with re-acquisition of resistance to chemotherapy. Resistance induced in newly formed CSCs is mediated by the anti-apoptotic molecule BCLXL and inhibition of BCLXL with the BH3 mimetic ABT-737 sensitizes these cancer cells toward chemotherapy. These data point to an important interplay between tumor cells and their microenvironment in the regulation of stemness and therapy resistance.
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Antineoplásicos/farmacologia , Fatores Biológicos/metabolismo , Compostos de Bifenilo/farmacologia , Fibroblastos/metabolismo , Regulação Neoplásica da Expressão Gênica , Células-Tronco Neoplásicas/metabolismo , Nitrofenóis/farmacologia , Sulfonamidas/farmacologia , Proteína bcl-X/genética , Antígeno AC133/genética , Antígeno AC133/metabolismo , Fatores Biológicos/farmacologia , Biomarcadores/metabolismo , Comunicação Celular , Morte Celular , Diferenciação Celular , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/farmacologia , Resistencia a Medicamentos Antineoplásicos , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Queratina-20/genética , Queratina-20/metabolismo , Mucina-2/genética , Mucina-2/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Piperazinas/farmacologia , Cultura Primária de Células , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Proteína bcl-X/metabolismoRESUMO
OBJECTIVE: This study aimed to assess the demographic characteristics, emergency department (ED) complaints, laboratory findings, and latent phase periods of patients who presented to the ED due to mushroom poisoning (MP) as well as the efficacy of conventional and hemofiltration therapies. METHOD: The study was conducted on patients who presented to the ED with MP between 2010 and 2012. The patient's demographic characteristics, complaints at the ED, latent phases, laboratory findings, and treatments of MP cases were evaluated. RESULTS: The mean age of patients was 38.03 ± 15.96, where 63.8% of them were female and 36.2% were male. Visits occurred most frequently in the autumn (32.6%). When presenting to the ED, the most frequent complaint was nausea-vomiting. The aspartate aminotransferase (AST), alanine aminotransferase (ALT), international normalised ratio (INR), and blood urea nitrogen values of patients with a latent phase between 0 h and 5 h were significantly lower than the values of patients with a latent phase between 6 h and 24 h. In this study, 62% of the patients (n = 36) had stomach lavage and received activated charcoal. Altogether, 55.2% of the patients had received conventional therapy, 37.9% of them received hemofiltration, and all of them received supportive treatment. The AST, ALT, and INR values of those who had received hemofiltration and conventional therapies were significantly higher than of those who received only supportive treatment (p < 0.01). CONCLUSION: Hemofiltration, in combination with conventional therapy, seems to be an effective treatment for reducing mortality in suspected MP cases involving late acting toxins.
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Serviço Hospitalar de Emergência/estatística & dados numéricos , Intoxicação Alimentar por Cogumelos/epidemiologia , Adolescente , Adulto , Idoso , Carvão Vegetal/uso terapêutico , Feminino , Hemofiltração , Humanos , Masculino , Pessoa de Meia-Idade , Intoxicação Alimentar por Cogumelos/tratamento farmacológico , Intoxicação Alimentar por Cogumelos/terapia , Penicilina G/uso terapêutico , Silibina , Silimarina/uso terapêutico , Turquia/epidemiologia , Adulto JovemRESUMO
Tumor heterogeneity is in part determined by the existence of cancer stem cells (CSCs) and more differentiated tumor cells. CSCs are considered to be the tumorigenic root of cancers and suggested to be chemotherapy resistant. Here we exploited an assay that allowed us to measure chemotherapy-induced cell death in CSCs and differentiated tumor cells simultaneously. This confirmed that CSCs are selectively resistant to conventional chemotherapy, which we revealed is determined by decreased mitochondrial priming. In agreement, lowering the anti-apoptotic threshold using ABT-737 and WEHI-539 was sufficient to enhance chemotherapy efficacy, whereas ABT-199 failed to sensitize CSCs. Our data therefore point to a crucial role of BCLXL in protecting CSCs from chemotherapy and suggest that BH3 mimetics, in combination with chemotherapy, can be an efficient way to target chemotherapy-resistant CSCs.
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Antineoplásicos/farmacologia , Apoptose , Neoplasias do Colo/patologia , Mitocôndrias/metabolismo , Células-Tronco Neoplásicas/fisiologia , Sobrevivência Celular , Neoplasias do Colo/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Humanos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células Tumorais Cultivadas , Proteína bcl-X/antagonistas & inibidoresRESUMO
Betulinic acid (BetA) is a plant-derived pentacyclic triterpenoid that exerts potent anti-cancer effects in vitro and in vivo. It was shown to induce apoptosis via a direct effect on mitochondria. This is largely independent of proapoptotic BAK and BAX, but can be inhibited by cyclosporin A (CsA), an inhibitor of the permeability transition (PT) pore. Here we show that blocking apoptosis with general caspase inhibitors did not prevent cell death, indicating that alternative, caspase-independent cell death pathways were activated. BetA did not induce necroptosis, but we observed a strong induction of autophagy in several cancer cell lines. Autophagy was functional as shown by enhanced flux and degradation of long-lived proteins. BetA-induced autophagy could be blocked, just like apoptosis, with CsA, suggesting that autophagy is activated as a response to the mitochondrial damage inflicted by BetA. As both a survival and cell death role have been attributed to autophagy, autophagy-deficient tumor cells and mouse embryo fibroblasts were analyzed to determine the role of autophagy in BetA-induced cell death. This clearly established BetA-induced autophagy as a survival mechanism and indicates that BetA utilizes an as yet-undefined mechanism to kill cancer cells.
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Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Mitocôndrias/metabolismo , Triterpenos/farmacologia , Animais , Linhagem Celular Tumoral , Ciclosporina/farmacologia , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Necrose , Triterpenos Pentacíclicos , Transdução de Sinais/efeitos dos fármacos , Ácido BetulínicoRESUMO
Metazoan parasites of the sand smelt Atherina boyeri Risso, 1810 in Lake Iznik were studied. A total of 271 specimens of A. boyeri, 208 female and 63 male, mean ( ± SD) total length 8.4 ± 2.2 cm (range 3.1-12.2 cm) and mean total weight 4.7 ± 3.5 g (range 0.1-11.7 g) were examined between June 2008 and May 2009 at monthly intervals. In 33 fish no parasites were found. In the other fish, four parasite species were recorded: Diplostomum sp. (prevalence 39.13%, mean intensity 3.50 ± 3.03); Tylodelphys clavata (prevalence 74.16%, mean intensity 10.41 ± 14.89); Bothriocephalus cf. acheilognathi (prevalence 40.59%, mean intensity 31.83 ± 57.74); and Eustrongylides excisus (prevalence 6.64%, mean intensity 1.16 ± 0.39). The mean abundance of Diplostomum sp., T. clavata and E. excisus was higher during the winter and early spring months. In contrast, the mean abundance of B. cf. acheilognathi was higher in the summer and autumn months. This distribution of the parasites was related to a change in the environment of A. boyeri from the pelagic zone to deeper water at the end of autumn and a change in food supply.
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Biodiversidade , Doenças dos Peixes/parasitologia , Helmintíase Animal/parasitologia , Helmintos/classificação , Helmintos/isolamento & purificação , Osmeriformes/parasitologia , Animais , Feminino , Lagos , Masculino , Carga Parasitária , Prevalência , Estações do Ano , TurquiaRESUMO
AIM: The peripheral nerves of the upper extremity are exposed to acute and chronic mechanical injuries in ice hockey players, because of the high repetition of motions, high muscular forces and extreme shoulder positions. This study was performed to evaluate the effect of ice hockey playing on the axillary, musculocutaneous and radial nerves crossing the upper arm region. METHODS: The ice hockey group consisted of 20 first-division male ice hockey players and the control group consisted of 20 non-active males. The neurophysiological study consisted of motor nerve conduction latency of the axillary, musculocutaneous and radial nerves. RESULTS: The values of distal motor latency (DML) of the axillary, radial and musculocutaneous nerves were significantly prolonged in the ice hockey players compared with the controls. Ice hockey can repetitively stress the upper extremity during shooting, because of forceful throwing to move the puck from the stick blade to the opponent's net. The mechanism of prolonged DML in the axillary nerve may both tract and compress as the axillary nerve stretches across the humerus during movement. From this study it emerged that using the biceps and coracobrachialis muscles can create notable muscle compartment pressure on the musculocutaneus nerve. The significant differences detected in the neurophysiologic study of the musculocutaneous nerve between the ice hockey players and controls may reflect the fact that the forces acting on the shoulder and the elbow during ice hockey matches can effectively influence DML. CONCLUSIONS: The authors suggest two plausible causes for prolonged radial nerve DML: direct compression by the hypertrophied triceps muscle and stretching of the arm. The study suggests it is likely that a combination of skeletal muscle hypertrophy and excessive biomechanical demands on neurological structures during ice hockey matches may be a major etiologic factor in compression of the axillary, musculocutaneous and radial nerves.
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Hóquei/fisiologia , Nervo Musculocutâneo/fisiologia , Condução Nervosa , Nervo Radial/fisiologia , Adolescente , Adulto , Traumatismos em Atletas/fisiopatologia , Estudos de Casos e Controles , Hóquei/lesões , Humanos , Masculino , Nervo Musculocutâneo/lesões , Doenças do Sistema Nervoso Periférico/fisiopatologia , Nervo Radial/lesões , Tempo de Reação/fisiologia , Extremidade Superior/lesões , Adulto JovemRESUMO
Characteristic features of the radiolytical intermediates produced in gamma irradiated solid sulfanilamide (SA) were investigated in the present work using ESR spectroscopy. SO(2), which is the most sensitive group to radiation of SA molecule, was found to be at the origin of radiation produced ionic radical species. The latters give rise to an axially symmetric and an isotropic ESR spectra so that their sum appears as a three line antisymmetric ESR spectrum. Heights of these lines measured with respect to the base line were used to monitor microwave, temperature, time-dependent and kinetic features of the radical species contributing to ESR spectrum. Based on the experimental results derived from this study, it was concluded that as in the case of other solid sulfonamides radiation, yield of solid SA is very low (G=0.5) compared with those obtained for sulfonamide aqueous solutions (G=3.5-5.1), so that SA and SA-containing drugs could be safely sterilized by radiation.
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Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres/química , Raios gama , Sulfanilamidas/química , Sulfanilamidas/efeitos da radiação , Simulação por Computador , Relação Dose-Resposta à Radiação , Compostos Inorgânicos , Cinética , Micro-Ondas , Análise Espectral , Sulfanilamida , Temperatura , Fatores de TempoRESUMO
The recent developments in light generation and detection techniques have opened new possibilities for optical medical imaging, tomography, and diagnosis at tissue penetration depths of ~10 cm. However, because light scattering and diffusion in biological tissue are rather strong, the reconstruction of object images from optical projections needs special attention. We describe a simple reconstruction method for diffuse optical imaging, based on a modified backprojection approach for medical tomography. Specifically, we have modified the standard backprojection method commonly used in x-ray tomographic imaging to include the effects of both the diffusion and the scattering of light and the associated nonlinearities in projection image formation. These modifications are based primarily on the deconvolution of the broadened image by a spatially variant point-spread function that is dependent on the scattering of light in tissue. The spatial dependence of the deconvolution and nonlinearity corrections for the curved propagating ray paths in heterogeneous tissue are handled semiempirically by coordinate transformations. We have applied this method to both theoretical and experimental projections taken by parallel- and fan-beam tomography geometries. The experimental objects were biomedical phantoms with multiple objects, including in vitro animal tissue. The overall results presented demonstrate that image-resolution improvements by nearly an order of magnitude can be obtained. We believe that the tomographic method presented here can provide a basis for rapid, real-time medical monitoring by the use of optical projections. It is expected that such optical tomography techniques can be combined with the optical tissue diagnosis methods based on spectroscopic molecular signatures to result in a versatile optical diagnosis and imaging technology.
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A new optical neural-network concept using the control of the modes of an injection laser by external feedback is described by a simple laser model. This approach uses the wavelength dispersed longitudinal modes of the laser as neurons and the amount of external feedback as connection weights. The predictions of the simple model are confirmed both with extensive numerical examples using the laser rate equations and also by experiments with GaAlAs injection lasers. The inputs and connection weights to this laser neural network are provided by external masks which control the amount of feedback reaching the laser. Stochastic learning is used to obtain weight masks for a small three-input and four-output neural net for the numerical and experimental examples. Winner-take-all and exclusive-or operations are obtained on the input set with different weight masks. Both of these operations are also obtained in experiments with a three-input/four-output laser neural network operating at an estimated speed greater than 10 GCPS. The eventual speed of this type of neural network hardware is expected to reach well within TCPS range if it is built in an optoelectronic integrated circuit with dimensions in the order of a mm. Different neural-network architectures possible with this approach are discussed.
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Describes a new approach for obtaining neural network functionality using fully distributed electronic transport rather than lumped electronic circuit elements. For this, vector mapping abilities of a two-dimensional nonlinear inhomogeneous layer are analyzed. This layer is modeled as an inhomogeneous inversion layer in a multiterminal field effect semiconductor device. The author gives computed results as examples of nonlinear vector mapping abilities including nontrivial logic functions with such a layer. These results are achieved by defining relative or differential output signals for the representation of the output information. The type of mapping achieved here is analogous to the one with high-order neural networks. The memory function in the author's structure is imbedded in the distribution of the inhomogeneities.
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Due to low back pain (LBP) and harmful effects of flying, questionnaires were sent to 71 helicopter pilots of the experimental group, 22 mechanics helicopter flyers and to the control group of 28 air-traffic controllers. The prevalence of LBP was the highest in helicopter pilots, then in helicomechanics and air-traffic controllers (53%, 50% and 36%). Effects of exposure to vibration, body posture and working load have not contributed significantly to the occurrence of LBP. LBP has not lead to an important difference in the strength of the back musculature, body mass index and spondylosis, that is, scoliosis. The necessity of further study of LBP and maintaining of specific preventive measures are indicated.