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1.
During fire emergencies, firefighters wear personal protective devices (PC) and a self-contained breathing apparatus (S.C.B.A.) to be protected from injuries. The purpose of this study was to investigate the differences of aerobic level in 197 firefighters (age: 34±7 yr; BMI: 24.4±2.3 kg.m-2), evaluated by a Queen’s College Step field Test (QCST), performed with and without fire protective garments, and to analyze the differences among age groups (<25 yr; 26-30 yr, 31-35 yr, 36-40 yr and >40 yr). Variance analysis was applied to assess differences (p < 0.05) between tests and age groups observed in absolute and weight-related values, while a correlation was examined between QCST with and without PC+S.C.B.A. The results have shown that a 13% of firefighters failed to complete the test with PC+S.C.B.A. and significant differences between QCST performed with and without PC+S.C.B.A. in absolute (F(1,169) = 42.6, p < 0.0001) and weight-related (F(1,169) = 339.9, p < 0.0001) terms. A better correlation has been found in L•min-1 (r=0.67) than in ml•kg-1•min-1 (r=0.54). Moreover, we found significant differences among age groups both in absolute and weight-related values. The assessment of maximum oxygen uptake of firefighters in absolute term can be a useful tool to evaluate the firefighters'' cardiovascular strain. 相似文献
2.
《Endocrine practice》2005,11(4):223-233
ObjectiveTo attempt to confirm a previous report of superior effectiveness of using two thyroid hormones rather than one hormone to treat hypothyroidism.MethodsThis trial attempted to replicate prior findings, which suggested that substituting 12.5 μg of liothyronine (LT3) for 50 μg of levothyroxine (LT4) might improve mood, cognition, and physical symptoms in patients with primary hypothyroidism. Additionally, this trial aimed to extend the previous findings to fatigue and to assess for differential effects in subjects with low fatigue and high fatigue at baseline. A randomized, double-blind, two-period, crossover design was used. At an endocrinology and diabetes clinic, 30 adult subjects with primary hypothyroidism stabilized on LT4 were recruited. Patients randomly assigned to treatment sequence 1 received their standard LT4 dose in one capsule and placebo in another. Patients assigned to sequence 2 received their usual LT4 dose minus 50 μg in one capsule and 10 μg of LT3 in the other. At the end of the first 6 weeks, subjects were crossed over to receive the other treatment. Carryover and treatment effects were assessed by t tests.ResultsOf the 30 enrolled study subjects, 27 completed the trial. The mean LT4 dose was 121 ± 26 μg/day at baseline. No significant differences in fatigue and symptoms of depression were found between treatments. Measures of working memory were unchanged. During substitution treatment, the free thyroxine index was reduced by 0.7 (P < 0.001), total serum thyroxine was reduced by 3.0 μg/dL (P < 0.001), and total serum triiodothyronine was increased by 20.5 ng/dL (P = 0.004).ConclusionWith regard to the outcomes measured, substitution of LT3 at a 1:5 ratio for a portion of baseline LT4 yielded no better results than did treatment with the original dose of LT4 alone. (Endocr Pract. 2005;11:223-233) 相似文献
3.
W.M. Abraham A. Wanner J.S. Stevenson G.A. Chapman 《Prostaglandins & other lipid mediators》1986,31(3)
Leukotriene (LT) D4 is a putative mediator of allergic asthma: inhaled LTD4 produces early and late increases in specific lung resistance (SRL) and slows tracheal mucus velocity (TMV) similat to inhaled antigen. In this study we examined the effects of an orally active LTD4/LTE4 antagonist, LY171883 [1-<2-Hydroxy-3-propyl-4-<4-(1H-Tetra-zol-5-yl) Butoxy>Phenyl>Ethanonel], on early and late changes in SRL and TMV following airway challenge with
antigen in conscious allergic sheep. SRL and TMV were measured before and up to 8 h and 24 h after antigen challenge after either LY171883 (30 mg/kg, p.o. 2 h before challenge) or placebo pretreatment. After placebo pretreatment antigen challenge resulted in significant early (483% over baseline) and late (221% over baseline) increases in SRL (n=9). LY171883 pretreatment, however, significantly reduced the early increase in SRL (163% over baseline) and blocked the late response. LY171883 did not prevent the antigen-induced fall in TMV from 5–8 h post challenge (n=6), but TMV recovered more rapidly in the drug trial returning to baseline values by 24 h. These results suggest that the generation of LTD4, and its metabolite LTE4, during airway anaphylaxis contributes to the early increase in SRL and is important for eliciting the late increase in SRL as well as contributing to the fall in TMV. 相似文献
4.
Grace E. Vincent Brad Aisbett Sarah J. Hall Sally A. Ferguson 《Chronobiology international》2016,33(6):657-666
ABSTRACTPlanned burning is a preventative strategy aimed at decreasing fuel loads to reduce the severity of future wildfire events. During planned burn operations, firefighters can work long shifts. Furthermore, remote burning locations may require firefighters to sleep away from home between shifts. The existing evidence surrounding firefighters’ sleep during such operations is exclusively anecdotal. The aims of the study were to describe firefighters’ sleep during planned burn operations and evaluate the impact of the key operational factors (shift start time, shift length and sleeping location) that may contribute to inadequate sleep. Thirty-three salaried firefighters were recruited from Australia’s fire agencies and sleep was measured objectively using wrist actigraphy for four weeks. All variables were examined in two conditions: (1) burn days, and (2) non-burn days. Time in bed, total sleep time, sleep latency and sleep efficiency were evaluated objectively. Subjective reports of pre- and post-sleep fatigue, sleep location, sleep quality, sleep quantity, number of times woken and sleep timing were also recorded. Analyses revealed no differences in measures of sleep quantity and quality when comparing non-burn and burn days. Total sleep time was less when planned burn shifts were >12 h. However, on burn days, work shift start time as well as sleeping location did not impact firefighters’ sleep quantity. Self-reported levels of pre- and post-sleep fatigue were greater on burn days compared to non-burn days. These findings indicate that sleep quantity and quality are not compromised during planned burn operations <12 h in duration. 相似文献
5.
Dennison KJ Mullineaux DR Yates JW Abel MG 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(4):1101-1109
Firefighting is a strenuous occupation that requires optimal levels of physical fitness. The National Fire Protection Association suggests that firefighters should be allowed to exercise on duty to maintain adequate fitness levels. However, no research has addressed the effect of exercise-induced fatigue on subsequent fire ground performance. Therefore, the primary purpose of this study was to determine the effect that a single exercise session had on the performance of a simulated fire ground test (SFGT). Secondarily, this study sought to compare the effect of physical training status (i.e., trained vs. untrained firefighters) on the performance of an SFGT. Twelve trained (age: 31.8 ± 6.9 years; body mass index [BMI]: 27.7 ± 3.3 kg·m(-2); VO2peak: 45.6 ± 3.3 ml·kg(-1)·min(-1)) and 37 untrained (age: 31.0 ± 9.0 years; BMI: 31.3 ± 5.2 kg·m(-2); VO2peak: 40.2 ± 5.2 ml·kg(-1)·min(-1)) male career firefighters performed a baseline SFGT. The trained firefighters performed a second SFGT after an exercise session. Time to complete the SFGT, heart rate, and blood lactate were compared between baseline and exercise SFGT (EX-SFGT) conditions. In the trained firefighters, time to complete the SFGT (9.6% increase; p = 0.002) and heart rate (4.1% increase; p = 0.032) were greater during the EX-SFGT compared with baseline, with no difference in post-SFGT blood lactate (p = 0.841). The EX-SFGT time of the trained firefighters was faster than approximately 70% of the untrained firefighters' baseline SFGT time. In addition, the baseline SFGT time of the trained firefighters was faster than 81% of the untrained firefighters. This study demonstrated that on-duty exercise training reduced the work efficiency in firefighters. However, adaptations obtained through regular on-duty exercise training may limit decrements in work efficiency because of acute exercise fatigue and allow for superior work efficiency compared with not participating in a training program. 相似文献
6.
A 60 day feeding trial was conducted to study the effect of dietary l-tryptophan on thermal tolerance and oxygen consumption rate of freshwater fish, mrigala, Cirrhinus mrigala reared under ambient temperature at low and high stocking density. Four hundred eighty fingerlings were distributed into eight experimental groups. Four groups each of low density group (10 fishes/75 L water) and higher density group (30 fishes/75 L water) were fed a diet containing 0, 0.68, 1.36 or 2.72% l-tryptophan in the diet, thus forming eight experimental groups namely, Low density control (LC) (basal feed +0% l-tryptophan); LT1 (basal feed+0.68% l-tryptophan); LT2 (basal feed+1.36% l-tryptophan); LT3 (basal feed+2.72% l-tryptophan); high density control (HC) (basal feed+0% l-tryptophan); HT1 (basal feed+0.68% l-tryptophan); HT2 (basal feed+1.36% l-tryptophan); and HT3 (basal feed+2.72% l-tryptophan) were fed at 3% of the body weight. The test diets having crude protein 34.33±0.23 to 35.81±0.18% and lipid 423.49±1.76 to 425.85±0.31 K Cal/100 g were prepared using purified ingredients. The possible role of dietary l-tryptophan on thermal tolerance and oxygen consumption rate was assessed in terms of critical thermal maxima (CTMax), critical thermal minima (CTMin), lethal thermal maxima (LTMax) and lethal thermal minima (LTMin). The CTMax, CTMin, LTMax and LTMin values were found to be significantly higher (p<0.05) in the treatment groups with CTMax 42.94±0.037 (LT2); LT Max 43.18±0.070 (LT2); CTMin 10.47±0.088 (LT2) and LTMin 9.42±0.062 (LT3), whereas the control group showed a lower tolerance level. The same trend was observed in the high density group (CTMax 42.09±0.066 (LT3); LTMax 43 23±0.067 (HT3); CTMin 10.98±0.040 (HT3) and LTMin 9.74±0.037 (HT3). However, gradual supplementation of dietary l-tryptophan in the diet significantly reduced the oxygen consumption rate in both the low density group (Y=−26.74x+222.4, r²=0.915) and the high density group (Y=−32.96x+296.5, r²=0.8923). Dietary supplementation of l-tryptophan at a level of 1.36% improved the thermal tolerance level and reduced the oxygen consumption rate in C. mrigala fingerlings. 相似文献
7.
Vijaya Saradhi UV Ling Y Wang J Chiu M Schwartz EB Fuchs JR Chan KK Liu Z 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(30):3045-3051
Curcumin and tetrahydrocurcumin (THC) have been found as potent DNMT1 inhibitors, but they suffer from low oral bioavailability and rapid metabolism in vivo. To circumvent these problems, two curcumin analogs: 1,7-bis(3,4-dimethoxyphenyl)-4,4-dimethyl-1,6-heptadiene-3,5-dione (TMC) and 1,7-bis(3,4-dimethoxyphenyl)-4-cyclohexyl-1,6-heptadiene-3,5-dione (DMCHC) have been synthesized to enhance their stability by blocking the two metabolic sites, the phenolic and C4 methylene moieties. Both compounds have shown inhibitory activity on M. SssI similar to that of curcumin and THC (Poster, M1114, AAPS, 2009). Preclinical pharmacokinetics has yet to be performed. In this paper, a simple liquid chromatography-tandem mass spectrometric method was developed for the determination of these four curcuminoids in cell medium and mouse plasma. The method showed linearity from 1 to 1000 ng/mL with the lower limit of quantification of 1 ng/mL in cell medium, and 5 ng/mL in mouse plasma for all test curcuminoids. The within-day coefficients of variation were found to be below 15% and the accuracy was in the range of 85-115%. This method was subsequently used to evaluate their stability in these matrices and a pilot pharmacokinetics of curcumin, DMCHC and TMC in mice after an intraperitoneal (i.p.) cassette dosing of 10mg/kg each. Curcuminoids degraded in two phases with terminal half lives of 186, 813, 724, and 2000 min for curcumin, THC, TMC, and DMCHC, respectively, in cell culture medium. In plasma, their respective half lives were 111, 232, 1202 and 3000 min. These data demonstrated that their stability is in the order curcumin相似文献
8.
Domenico Cozzolino Anna Grandone Antonio Cittadini Giuseppe Palmiero Giovanni Esposito Annamaria De Bellis Raffaello Furlan Silverio Perrotta Laura Perrone Daniele Torella Emanuele Miraglia del Giudice 《PloS one》2015,10(4)
Background
The prevalence of obesity is increasing among children/adolescents. Subtle cardiovascular abnormalities, responsible for a higher mortality later in life, have been reported in obese children/adolescents. The aims of the study were to evaluate cardiovascular autonomic regulation, by means of spectrum analysis of R-R interval variability, and myocardial function, by means of standard and tissue Doppler echocardiography, in a group of non-hypertensive asymptomatic obese children and adolescents; furthermore, the influence of insulin resistance was tested.Subjects and Methods
R-R interval variability was analyzed during both the 70° head-up tilt and 24-hour electrocardiographic holter monitoring. Spectrum analysis of R-R interval variability provided the indices of sympathetic (low frequency [LFRR]) and vagal (high frequency [HFRR]) modulation of the sinoatrial node. Homeostasis model assessment of insulin resistance (HOMA-IR) was used to classify obese children/adolescents (n=72) as insulin resistant (n=37) and non-insulin resistant (n=35).Results
In obese subjects: a) left ventricular mass was significantly (p<0.05) increased, whereas both the e/a ratio and the e''/a'' ratio were decreased; b) at rest, HFRR was lower, and the LFRR/HFRR ratio was higher; c) during tilting, magnitude of tilt-induced inhibition of HFRR was lower; d) during 24-hour electrocardiographic holter monitoring, LFRR and the LFRR/HFRR ratio were higher, whereas HFRR was lower; e) HOMA-IR inversely correlated with both the e''/a'' ratio (r=-0.655; p<0.001) and the tilt-induced LFRR/HFRR ratio (r=-0.933; p<0.001); and, f) the e''/a'' ratio correlated with the tilt-induced LFRR/HFRR ratio (r=0.501; p<0.001). Moreover, HFRR at rest, magnitude of tilt-induced HFRR reduction, and the e''/a'' ratio in insulin resistant obese children/adolescents were markedly lower when compared with the remaining subjects.Conclusions
Subclinical abnormalities of myocardial function and of cardiac autonomic regulation were closely associated in obese children/adolescents and both correlated with the degree of insulin resistance. 相似文献9.
Wincenty Kilarski 《Cell and tissue research》1973,136(4):535-544
Summary The sarcoplasmic reticulum of the white and red muscle fibers in the extrinsic eye muscle of the tench (Tinca tinca L.) differs in its organization. The SR of the white fibers is organized according to the Z type, the SR of the red fibers according to the A/I type. In order to estimate the volume and surface of the SR component in both types of muscle fibers, a stereological analysis was carried out.The volume of the SR expressed as a volume density (Vv
SR) is twofold greater in the white than in the red muscle fibers. The surface of the SR, expressed as surface density (Sv
SR) is 20,5% larger in the white muscle fibers.I extend my sincerest thanks to Prof. E. R. Weibel for helpful discussion and instructions in the use of his method and to Mrs. Anna Mleczko-Michalik for skillfull technical assistance. — This work was supported by Polish Academy of Science, project number 09.4.1.4.5. 相似文献
10.
《Endocrine practice》2010,16(3):357-370
ObjectiveTo survey physicians to determine whether potency and consistency issues with levothyroxine sodium (LT4) have been resolved and to assess current experience regarding safety of substituting LT4 products.MethodsMembers of the American Association of Clinical Endocrinologists, American Thyroid Association, and The Endocrine Society collaborated to create a survey instrument that would effectively sample the clinical experience of their society members and frequent prescribers of LT4. More than 18 000 e-mailed requests for information were generated, and the Web sites of each society provided links to the data collection form. The survey provided an opportunity to collect clinical observations of adverse events or product availability problems from physicians caring for patients with thyroid disease who required use of contemporary LT4 preparations.ResultsAfter adjustment for known reasons for unstable results from thyroid function tests, 199 reports of adverse events associated with changes in thyrotropin values were further analyzed. One hundred seventy-seven reports (88.9%) were associated with a change in the source of LT4; no change was noted in 21(10.6%). Details regarding the circumstances of the change were provided in 167 of the 177 reports (94.4%), The reporting physicians themselves or their office staff had changed the LT4 preparation in only 1 of the 167 cases (0.6%). The remainder of changes had been made by the patient’s pharmacy, either with the physician’s knowledge (in 13 of 167 cases [7.8%]) or without his/her knowledge (in 153 of 167 cases [91.6%]). Fifty-four of 199 cases (27.1%) described serious adverse events; 52 of these (96.3%) were associated with a substitution of one LT4 preparation for another.ConclusionsThe clinical use of contemporary LT4 products continues to be associated with some adverse outcomes. A small number of reports were associated with continued use of the same LT4 products. The most frequently reported adverse outcomes were associated with the approved generic substitution of LT4 products, frequently without the prescribing physician’s knowledge.(Endocr Pract. 2010;16:357-370) 相似文献
11.
Evaluating how autotrophic (SRA), heterotrophic (SRH) and total soil respiration (SRTOT) respond differently to changes of environmental factors is critical to get an understanding of ecosystem carbon (C) cycling and its feedback processes to climate change. A field experiment was conducted to examine the responses of SRA and SRH to water and nitrogen (N) addition in a temperate steppe in northern China during two hydrologically contrasting growing seasons. Water addition stimulated SRA and SRH in both years, and their increases were significantly greater in a dry year (2007) than in a wet year (2006). N addition increased SRA in 2006 but not in 2007, while it decreased SRH in both years, leading to a positive response of SRTOT in 2006 but a negative one in 2007. The different responses of SRA and SRH indicate that it will be uncertain to predict soil C storage if SRTOT is used instead of SRH to estimate variations in soil C storage. Overall, N addition is likely to enhance soil C storage, while the impacts of water addition are determined by its relative effects on carbon input (plant growth) and SRH. Antecedent water conditions played an important role in controlling responses of SRA, SRH and the consequent SRTOT to water and N addition. Our findings highlight the predominance of hydrological conditions in regulating the responses of C cycling to global change in the semiarid temperate steppe of northern China. 相似文献
12.
Georg Thaler 《Inorganica chimica acta》2005,358(9):2833-2837
Reaction of tBu2(Me3Si)C5H2Li with S2Cl2 leads to [tBu2(Me3Si)C5H2]2S2. This compound exists as a pair of diastereomers (1,2) with sulfur in an allylic position of the cyclopentadiene system. Each diastereomer exists as a racemate of RS,SR and RR,SS enantiomers, respectively. 1 rapidly, 2 slowly convert below room temperature to a pair of diastereomers (3,4) with sulfur in vinylic position. Again, each diastereomer exists as a racemate of RS,SR and RR,SS enantiomers. 3 and 4 are the stable constitutional isomers at ambient temperatures and do not interconvert. The structures of 2, 3 and 4 have been determined by single crystal X-ray diffraction. 相似文献
13.
Spontaneous calcium (Ca) sparks are initiated by single ryanodine receptor (RyR) opening. Once one RyR channel opens, it elevates local [Ca] in the cleft space ([Ca]Cleft), which opens other RyR channels in the same Ca release unit (CaRU) via Ca-induced Ca-release. Experiments by Zima et al. (J. Physiol. 588:4743–4757, 2010) demonstrate that spontaneous Ca sparks occur only when intrasarcoplasmic-reticulum (SR) [Ca] ([Ca]SR) is above a threshold level, but that RyR-mediated SR Ca leak exists without Ca sparks well below this threshold [Ca]SR. We examine here how single RyR opening at lower [Ca]SR can fail to recruit Ca sparks at a CaRU, while still contributing to SR Ca leak. We assess this using a physiologically detailed mathematical model of junctional SR Ca release in which RyR gating is regulated by [Ca]SR and [Ca]Cleft. We find that several factors contribute to the failure of Ca sparks as [Ca]SR declines: 1), lower [Ca]SR reduces driving force and thus limits local [Ca]Cleft achieved and the rate of rise during RyR opening; 2), low [Ca]SR limits RyR open time (τO), which further reduces local [Ca]Cleft attained; 3), low τO and fast [Ca]Cleft dissipation after RyR closure shorten the opportunity for neighboring RyR activation; 4), at low [Ca]SR, the RyR exhibits reduced [Ca]Cleft sensitivity. We conclude that all of these factors conspire to reduce the probability of Ca sparks as [Ca]SR declines, despite continued RyR-mediated Ca leak. In addition, these same factors explain the much lower efficacy of L-type Ca channel opening to trigger local SR Ca release at low [Ca]SR during excitation-contraction coupling. Conversely, all of these factors are fundamentally important for increasing the propensity for pro-arrhythmic Ca sparks and waves in cardiac myocytes at high [Ca]SR. 相似文献
14.
Drauzio E. N. Rangel Aquiles E. Piedrabuena Isaac Roitman Claudio L. Messias 《Archives of insect biochemistry and physiology》2020,105(4):e21745
Chagas disease is one of the most important insect-vectored diseases in Brazil. The entomopathogenic fungus Metarhizium anisopliae was evaluated against nymphs and adults of Panstrongylus megistus, Triatoma infestans, and T. sordida. Pathogenicity tests at saturated humidity demonstrated high susceptibility to fungal infection. The shortest estimates of 50% lethal time (LT50) for P. megistus varied from 4.6 (isolate E9) to 4.8 days (genetically modified strain 157p). For T. infestans, the shortest LT50 was 6.3 (E9) and 7.3 days (157p). For T. sordida, the shortest LT50 was 8.0 days (157p). The lethal concentration sufficient to kill 50% of T. infestans (LC50) was 1.9 × 107 conidia/ml for strain 157p. In three chicken coops that were sprayed with M. anisopliae, nymphs especially were well controlled, with a great population reduction of 38.5% after 17 days. Therefore M. anisopliae performed well, controlling Triatominae in both laboratory and field studies. 相似文献
15.
《Endocrine practice》2014,20(9):925-929
ObjectiveOriginal absorption studies for levothyroxine (LT4) were validated using total thyroxine (TT4) measurements. Free thyroxine (FT4) has largely supplanted TT4 in clinical practice. The objective of our study was to assess the clinical utility of FT4 in oral LT4 absorption testing.MethodsIn this retrospective electronic health record analysis, we recorded data of patients who underwent LT4 oral absorption testing between November 2010 and January 2012 because of persistent hypothyroidism despite a greater than anticipated weight-based dose of LT4. Patients included had primary hypothyroidism and an absorption test with assessment of both TT4 and FT4 measured at times 0, 30, 60, 90, 120, 180, 240, 300, and 360 minutes. The test was conducted with 1 mg (five 200-μg tablets) of Synthroid® after an overnight fast by a standard nonisotopic method.ResultsA total of 10 patients (3 men/7 women) underwent absorption testing. Prior to testing, the median daily LT4 dose was 250 μg (range, 150 to 350 μg). Three patients were also on liothyronine (10, 20, or 50 μg daily). Based on the calculated amount absorbed, 1 patient demonstrated subnormal absorption, and 9 patients were normal. Median body mass index was 33 kg/m2 (range, 21 to 50 kg/m2). Median calculated absorption was 105% (range, 3.7 to 195.6%). The correlation comparing FT4 and TT4 was 0.88 (95% confidence interval, 0.56 to 0.97, P < .001), a significant correlation.ConclusionFT4 and TT4 correlated highly, even in patients who were severely hypothyroid; FT4 may be used interchangeably with TT4 as a qualitative assessment of suspected malabsorption using an oral LT4 absorption test. (Endocr Pract. 2014;20:925-929) 相似文献
16.
Abel MG Mortara AJ Pettitt RW 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(10):2895-2901
Firefighters are required to perform a variety of strenuous occupational tasks that require high levels of both aerobic and anaerobic fitness. Thus, it is critical that firefighters train at an appropriate intensity to develop adequate levels of aerobic and anaerobic fitness. Circuit training is a unique training method that stresses both energy systems and therefore may be a viable training method to enhance firefighter preparedness. Thus, the purpose of this study was to compare the aerobic and anaerobic intensities of a circuit-based workout to physiological data previously reported on firefighters performing fire suppression and rescue tasks. Twenty career firefighters performed a workout that included 2 rotations of 12 exercises that stressed all major muscle groups. Heart rate was recorded at the completion of each exercise. Blood lactate was measured before and approximately 5 minutes after the workout. The workout heart rate and post-workout blood lactate responses were statistically compared to data reported on firefighters performing fire suppression and rescue tasks. The mean circuit-training heart rate was similar to previously reported heart rate responses from firefighters performing simulated smoke-diving tasks (79 ± 5 vs. 79 ± 6% maximum heart rate [HRmax], p = 0.741), but lower than previously reported heart rate responses from firefighters performing fire suppression tasks (79 ± 5 vs. 88 ± 6% HRmax, p < 0.001). The workout produced a similar peak blood lactate compared to that when performing firefighting tasks (12 ± 3 vs. 13 ± 3 mmol·L(-1), p = 0.084). In general, the circuit-based workout produced a lower cardiovascular stress but a similar anaerobic stress as compared to performing firefighting tasks. Therefore, firefighters should supplement low-intensity circuit-training programs with high-intensity cardiovascular and resistance training (e.g., ≥85% 1-repetition maximum) exercises to adequately prepare for the variable physical demands of firefighting. 相似文献
17.
18.
Aims: Our study was conducted to evaluate the potent protective effects of oral administration of probiotic Lactobacillus strains against influenza virus (Flu) infection in a mouse model. Method and Results: Lyophilized Lactobacillus rhamnosus GG (LGG) and Lactobacillus gasseri TMC0356 (TMC0356) were orally administered to BALB/c mice for 19 days. The test mice were intranasally infected with Flu A/PR/8/34 (H1N1) on day 14, and any changes in clinical symptoms were monitored. After 6 days of infection, the mice were killed and pulmonary virus titres were determined. The clinical symptom scores of mice administered oral LGG and TMC0356 were significantly ameliorated, compared to those of the control mice (P < 0·01). The pulmonary virus titres of the mice fed LGG and TMC0356 were also significantly decreased compared to those of control mice (P < 0·05). Conclusions: These results indicate that oral administration of lactobacilli, such as LGG and TMC0356, might protect a host animal against Flu infection. Significance and Impact of the Study: These results demonstrate that oral administration of selected lactobacilli might protect host animals from Flu infection by interactions with gut immunity. 相似文献
19.
Masanori Hoshino Koichi Yajima Yasutaka Suzuki Akira Okahira 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1994,661(2)
A stereospecific high-performance liquid chromatographic method has been developed for the determination of four diastereomers of nadolol in plasma. After the nadolol diastereomers were extracted from plasma using an Extrelut-1 solid-phase extraction cartridge, they were derivatized with (R)-(−)-1-(1-naphthyl)ethylisocyanate to form urea derivatives. These derivatives were then separated on a YMC-AM-303 ODS column using water—acetonitrile (60:40, v/v). The calibration curves of (SR)-, (RS)-, (SS)- and (RR)-nadolol were linear over the range 2.5–200 ng/ml, and the correlation coefficient (r) of the curves were higher than 0.9991 for each diastereomer. The limit of quantification was 2.5 ng/ml for each diastereomer in plasma. This method was used for a pharmacokinetic study in four dogs after oral administration of nadolol (1 mg/kg). The plasma concentrations of nadolol diastereomers showed no significant differences in Cmax, Tmax or AUC values. The assay appears to be readily applicable to the study of diastereoselective nadolol pharmacokinetics in animals and humans. 相似文献
20.
Characterization of a high-affinity monoclonal antibody specific for CD44v6 as candidate for immunotherapy of squamous cell carcinomas 总被引:5,自引:0,他引:5
K.-H. Heider Marlies Sproll Susanne Susani Erik Patzelt Paul Beaumier Elinborg Ostermann Horst Ahorn Günther R. Adolf 《Cancer immunology, immunotherapy : CII》1996,43(4):245-253
Variant isoforms of CD44, a family of cell-surface glycoproteins generated by alternative splicing and post-translational
modifications, are expressed in a variety of human tumors and play important roles in tumor progression and metastasis formation.
The murine monoclonal IgG1 antibody VFF18, specific for an epitope encoded by human CD44 variant exon 6, binds with high affinity
to the recombinant protein (K
d = 1.7×10–10 M) as well as to tumor cell lines in vitro, and is suitable for immunohistochemical analysis of human tumors. Screening of
more than 500 tumor samples of different histogenesis showed that VFF18 most strongly and uniformly reacts with squamous cell
carcinomas (SCC). Detailed analysis of 185 SCC (head and neck, lung, skin) confirmed reactivity of the antibody with 99% of
the samples, with intense and homogeneous staining of the tumor cells in the majority of cases, whereas reactivity of VFF18
with normal tissues is limited to certain epithelia and activated lymphocytes. When radiolabelled VFF18 was administered to
nude mice bearing human epidermoid carcinoma (A-431) xenograft, fast and selective tumor uptake of the radioimmunoconjugate
with a maximum of 18% of the injected dose per gram of tissue was observed. Taken together, these data suggest that mAb VFF18
is a promising targeting vehicle for radioimmunotherapy of squamous cell carcinomas in humans.
Received: 9 September 1996 / Accepted: 25 September 1996 相似文献