895 resultados para Military medicine
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At the present time, protein folding is an extremely active field of research including aspects of biology, chemistry, biochemistry, computer science and physics. The fundamental principles have practical applications in the exploitation of the advances in genome research, in the understanding of different pathologies and in the design of novel proteins with special functions. Although the detailed mechanisms of folding are not completely known, significant advances have been made in the understanding of this complex process through both experimental and theoretical approaches. In this review, the evolution of concepts from Anfinsen's postulate to the "new view" emphasizing the concept of the energy landscape of folding is presented. The main rules of protein folding have been established from in vitro experiments. It has been long accepted that the in vitro refolding process is a good model for understanding the mechanisms by which a nascent polypeptide chain reaches its native conformation in the cellular environment. Indeed, many denatured proteins, even those whose disulfide bridges have been disrupted, are able to refold spontaneously. Although this assumption was challenged by the discovery of molecular chaperones, from the amount of both structural and functional information now available, it has been clearly established that the main rules of protein folding deduced from in vitro experiments are also valid in the cellular environment. This modern view of protein folding permits a better understanding of the aggregation processes that play a role in several pathologies, including those induced by prions and Alzheimer's disease. Drug design and de novo protein design with the aim of creating proteins with novel functions by application of protein folding rules are making significant progress and offer perspectives for practical applications in the development of pharmaceuticals and medical diagnostics.
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There is evidence concerning the participation of reactive oxygen species in the etiology and physiopathology of human diseases, such as neurodegenerative disorders, inflammation, viral infections, autoimmune pathologies, and digestive system disorders such as gastrointestinal inflammation and gastric ulcer. The role of these reactive oxygen species in several diseases and the potential antioxidant protective effect of natural compounds on affected tissues are topics of high current interest. To consider a natural compound or a drug as an antioxidant substance it is necessary to investigate its antioxidant properties in vitro and then to evaluate its antioxidant functions in biological systems. In this review article, we shall consider the role of natural antioxidants derived from popular plants to reduce or prevent the oxidative stress in gastric ulcer induced by ethanol.
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Kartta kuuluu A. E. Nordenskiöldin kokoelmaan
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Despite the high prevalence of sleep disorders, many healthcare professionals and lay people have little knowledge of Sleep Medicine. Mindful of such a reality, in 2001 the Sleep Institute of the Associação Fundo de Incentivo à Psicofarmacologia launched a campaign to increase Sleep Medicine awareness. Media features, exhibitions, inserts, and classes were used to reach 2,000,000 people and 55,000 healthcare professionals during the period from 2001 to 2004. To evaluate this program, we compared data for polysomnography referrals to the Institute in 2000 and in 2004. A total of 8805 referrals were evaluated (2000: 2164; 2004: 6641). Over the 4 years of the program, the number of beds increased by 43%; more women were referred (31 vs 37%; P < 0.001), mainly with a diagnostic hypothesis of sleep-disorder breathing (SDB). SDB was the most frequent diagnostic hypothesis in 2000 and 2004. In 2004 there were fewer referrals without a diagnostic hypothesis (27 vs 21%; P < 0.001) and for controlling surgically treated SDB (2.3 vs 1.6%; P < 0.05), and an increase in the following diagnostic hypotheses: non-invasive treatment of SDB (8.3 vs 12.3%; P < 0.001) and insomnia (3.5 vs 6.5%; P < 0.001). Insomnia diagnostic hypothesis was better correlated with SDB on referral documents in 2004 and less with a diagnostic hypothesis of limb movement disturbance. The program helped increase polysomnography referrals, particularly among women. Healthcare professionals appear to have a more developed understanding of sleep disorders.
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The objective of the present study was to determine the impact of acute short-term exposure to air pollution on the cardiorespiratory performance of military fireman living and working in the city of Guarujá, São Paulo, Brazil. Twenty-five healthy non-smoking firemen aged 24 to 45 years had about 1 h of exposure to low and high levels of air pollution. The tests consisted of two phases: phase A, in Bertioga, a town with low levels of air pollution, and phase B, in Cubatão, a polluted town, with a 7-day interval between phases. The volunteers remained in the cities (Bertioga/Cubatão) only for the time required to perform the tests. Cumulative load 10 ± 2 min-long exertion tests were performed on a treadmill, consisting of a 2-min stage at a load of 7 km/h, followed by increasing exertion of 1 km h-1 min-1 until the maximum individual limit. There were statistically significant differences (P < 0.05) in anaerobic threshold (AT) between Cubatão (35.04 ± 4.91 mL kg-1 min-1) and Bertioga (36.98 ± 5.62 mL kg-1 min-1; P = 0.01), in the heart rate at AT (AT HR; Cubatão 152.08 ± 14.86 bpm, Bertioga 157.44 ± 13.64 bpm; P = 0.001), and in percent maximal oxygen consumption at AT (AT%VO2max; Cubatão 64.56 ± 6.55%, Bertioga 67.40 ± 5.35%; P = 0.03). However, there were no differences in VO2max, maximal heart rate or velocity at AT (ATvel) observed in firemen between towns. The acute exposure to pollutants in Cubatão, SP, caused a significant reduction in the performance at submaximal levels of physical exertion.
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Serologic data on diseases that are preventable by vaccines are necessary to evaluate the success of immunization programs and to identify susceptible subgroups. In the present study, we determined serum IgG levels against diphtheria toxin of military and civilian blood donors (N = 75; 69.3% males and 30.7% females) aged 18-64 years, from the Brazilian Army Biology Institute, Rio de Janeiro, using a commercial diphtheria kit (Diphtheria IgG ELISA; IBL, Germany). Most (63%) unprotected military donors were from the older age group of 41 to 64 years. In contrast, the majority (71%) of young military donors (18 to 30 years) were fully protected. About half of the military donors aged 31 to 40 years were protected against diphtheria. Among the civilians, about 50% of persons aged 18 to 30 years and 31 to 40 years had protective antibody levels against diphtheria as also did 64% of individuals aged 41 to 64 years. All civilians had a similar antibody response (geometric mean = 0.55 IU/mL) independent of age group. Military donors aged 18-30 years had higher IgG levels (geometric mean = 0.82 IU/mL) than military donors of 41-64 years (geometric mean = 0.51 IU/mL; P > 0.05). In conclusion, the existence of a considerable proportion of susceptible adults supports the position that reliable data on the immune status of the population should be maintained routinely and emphasizes the importance of adequate immunization during adulthood.
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It has been demonstrated that carbon nanotubes (CNTs) associated with sodium hyaluronate (HY-CNTs) accelerate bone repair in the tooth sockets of rats. Before clinical application of HY-CNTs, it is important to assess their biocompatibility. Moreover, cardiac toxicity may be caused by the translocation of these particles to the blood stream. The aim of this study was to evaluate possible changes in cardiovascular function in male Wistar rats whose tooth sockets were treated with either CNTs or HY-CNTs (100 μg/mL, 0.1 mL). Blood pressure and heart rate were monitored in conscious rats 7 days after treatment. Cardiac function was evaluated using the Langendorff perfusion technique. The data showed no changes in blood pressure or heart rate in rats treated with either CNTs or HY-CNTs, and no significant changes in cardiac function were found in any of the groups. To confirm these findings, experiments were conducted in rats injected intraperitoneally with a high concentration of either CNTs or HY-CNTs (0.75 mg/kg). The same parameters were analyzed and similar results were observed. The results obtained 7 days following injection indicate that the administration of low concentrations of CNTs or HY-CNTs directly into tooth sockets did not cause any significant change in cardiovascular function in the rats. The present findings support the possibility of using these biocomposites in humans.
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Puolustusvoimien fyysisen koulutuksen tavoitteena on tuottaa toimintakykyisiä sotilaita kriisi- ja sodanajan joukkoihin. Liikuntakoulutuksella tuetaan varusmiesten fyysistä koulutusta, ja yhtenä tavoitteena on aktivoida liikunnalliseen elämäntapaan myös reservissä. Varusmiesten lähtökunto palvelukseen astuttaessa on ollut laskusuhdanteessa jo useamman vuosikymmenen ajan, joten sen valossa uusien harjoittelumuotojen ja lajien tutkiminen on ajankohtaista. Tutkimustyön aiheena olevan Military Crosstraining -harjoittelun voidaan sanoa olevan CrossFitin® sotilassovellus, joka urheilu- ja harjoittelumuotona kehittää mahdollisimman monipuolisesti harjoittelijan suorituskykyä eli kestävyyttä ja lihaskuntoa. Tutkimustyön tarkoituksena oli selvittää, millaisia vaikutuksia toiminnallisella ja korkea intensiteettisellä Military Crosstraining -tyyppisellä fyysisellä harjoittelulla (MCH) on varusmiesten fyysisen suorituskyvyn kehittymiseen voimassa olevien normien mukaiseen koulu-tukseen (NH) verrattuna. Työssä vertailtiin kahden samankaltaisen, mutta eri tyyppistä lihaskunto- ja kestävyysharjoittelua tehneen varusmiesjoukon fyysisen suorituskyvyn kehittymistä kuuden kuukauden varusmiespalveluksen aikana. Koehenkilöt olivat jääkäri- ja panssarintorjuntaohjusjoukkueissa palvelleita miehistöön kuuluvia varusmiehiä (n=110, ikä 20,1 ± 0,4, paino 79,3 ± 12,3 kg, pituus 1,81 ± 0,06 m, BMI 24,3 ± 3,3). Kvantitatiivinen tutkimus perustui normin mukaisten varusmiesten kuntotestien sekä kehonkoostumuksen tulo- ja lähtötestien tuloksiin. Tilastolliset analyysit tehtiin SPSS 22 ohjelmalla. Muuttujien välisiä yhteyksiä selvitettiin Pearsonin sekä Spearmanin korrelaa-tiokertoimilla. Ryhmien keskiarvojen välisiä eroja sekä muuttujien muutoksia selvitettiin kaksisuuntaisella T-testillä sekä mediaanitestillä. Lähtötilanteessa ryhmät olivat fyysiseltä kunnoltaan käytännössä samantasoisia. Tutkimuk-sessa ei havaittu merkitseviä eroja (p<0.05) ryhmien välillä kuntotestien lopputuloksissa eikä kestävyys- ja lihaskunnon kehityksessä, vaikkakin kehitys molemmilla oli huomattavaa (p<0.001). Suurimmat erot havaittiin kehon painoissa ja BMI:ssa ja niiden muutoksissa (p<0.001). MCH:n kehonpainossa ja BMI:ssa ei tapahtunut juuri muutoksia. Kehonpainojen erotus kasvoi oli 6,5 %:sta 9,4 %:iin (p>0.001), NH:n painon ollessa pienempi. BMI:n erot kasvoivat vastaavasti 5,2 %:sta 8,4 %:iin (p<0.001). Johtopäätöksenä todettakoon, että mahdollisesti Military Crostraining -tyyppinen harjoittelu lisää lihasmassaa normaalia liikuntakoulutusta enemmän aerobisen kunnon siitä kuitenkaan kärsimättä. Tällä olisi positiivisia vaikutuksia moniin sotilaan kenttätehtäviin, kuten haavoittuneen evakuointiin, taakaan tai kuorman kantoon sekä raskaiden tavaroiden nostamiseen.