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cDNA cloning, sequence analysis and tissue distribution of rat preproendothelin-1 mRNA.

We report the cloning of a full-length cDNA encoding rat preproendothelin-1 (preproET-1). The predicted rat preproET-1 consists of 202 amino acid residues and highly similar to human, porcine and bovine preproET-1, respectively. The deduced 21-residue sequence of mature rat ET-1 is identical to human, porcine, canine and bovine ET-1. As in other mammalian species, the mature ET-1 is predicted to be produced from a 39-residue big ET-1 in the rat. Northern blot analysis showed that a single 2.3-kb preproET-1 mRNA is expressed not only in vascular endothelial cells but also in other rat tissues, including the lung, brain, uterus, stomach, heart, adrenal gland and kidney. These findings suggest that ET-1 may play roles as a local mediator in multiple organs both within and outside the cardiovascular system in the rat.

Amino Acid Sequence↗

HIV outbreak among injecting drug users in the Helsinki region: social and geographical pockets.

BACKGROUND: Incidence of newly diagnosed HIV infections among injecting drug users (IDUs) in Helsinki rose from 0 per 100,000 inhabitants in 1997 to 2.9 in 1998 and to 11.1 in 1999. Thereafter incidence declined to 2.1 in 2003. METHODS: Data were collected from interviews with HIV-positive IDUs who attended the University Hospital in Helsinki from 1998 until 2003. We studied the sociodemographic profile and spatial distribution of IDUs who were diagnosed in the beginning of the outbreak and those diagnosed later. The indicator for the spatial differentiation within the metropolitan area is % employed males aged 25-64. RESULTS: The outbreak occurred among a marginalized population of IDUs characterized by a long history of injecting drug use (10.7 years), mean age 32 years, homelessness (66.3%), history of imprisonment (74.7%) and psychiatric hospital care (40.6%). Compared with 98 early cases diagnosed during the first 2 years until 2000, 47 recent cases diagnosed after 2001 were 4 years older, and as marginalized. Except for the city centre, both early and recent cases had been living or using drugs in the same deprived neighbourhoods with the highest unemployment rates. Up to 40% of cases in the two big geographical clusters did not have contact with the city centre, where the needle exchange services were available. CONCLUSIONS: The Finnish HIV outbreak is restricted socially to a very marginalized IDU population, and spatially to local pockets of poverty. In low prevalence countries, prevention programs should be targeted early at high-risk areas and populations.

Adult↗

Processing and metabolism of endothelin peptides by porcine lung membranes.

The processing and metabolism of big endothelin-1 (big ET-1) and endothelin-1 (ET-1) by a membrane fraction from pig lung was examined. The principal activity in this membrane fraction hydrolyzing ET-1 was identified as endopeptidase-24.11 (EC 3.4.24.11) by inhibitory and immunological criteria. More than 90% of this endopeptidase-24.11 activity could be removed by immunoadsorption. ET-converting activity was partially purified from the solubilized membrane fraction by lectin chromatography on a Ricinus communis agglutinin-120-agarose column followed by immunodepletion of endopeptidase-24.11. The production of the C-terminal fragment of big ET-1 could be detected in this partially purified preparation and was inhibited by phosphoramidon (10 microM) but not by thiorphan (10 microM). The fluorogenic substrate succinyl-Ile-Ile-Trp-7-amido-4-methylcoumarin was hydrolyzed by pig lung membranes, but this activity was insensitive to phosphoramidon, suggesting that neither endopeptidase-24.11 nor endothelin-converting enzyme hydrolyze this substrate. Purified endopeptidase-24.11 also failed to hydrolyze the fluorogenic peptide.

Amino Acid Sequence↗

Structure of the precursor of Xenopus laevis endothelin-3 and phylogenetic analysis.

Endothelin (ET)-related receptors homologous to mammalian receptors have been cloned from Xenopus laevis, indicating that ET-related ligands may be present in this species. Here we cloned cDNAs encoding preproendothelin-3 (PPET-3) from the X. laevis intestinal cDNA library. X. laevis ET-3 cDNA encodes 201 amino acids, including a 20-amino-acid putative signal sequence, as well as mature ET-3, big ET-3, and ET-3-like sequences. X. laevis ET-3 differs by one amino acid from mammalian ET-3, and is identical to frog ET-3 recently purified from Rana ridibunda. This sequence together with other published PPET sequences were used to analyze the phylogenetic relationship among all ET family genes. This is the first report of the cDNA encoding the precursor protein of ET-3 in a non-mammalian species.

Amino Acid Sequence↗

Hepatic gene mutations induced in Big Blue rats by both the potent rat liver azo-carcinogen 6BT and its reported noncarcinogenic analogue 5BT.

The potent rat liver carcinogen 6-p-dimethylaminophenylazobenzthiazole (6BT) and its reported noncarcinogenic analogue 5-p-dimethylaminophenylazobenzthiazole (5BT; evaluated for carcinogenicity under the similar limited bioassay conditions used for 6BT) have been studied in order to seek an explanation for their different carcinogenic activities. Both compounds act as DNA-damaging agents to the rat liver, and both have now been shown to induce lacI (-) gene mutations in the liver of Big Blue(trade mark) transgenic rats. Both compounds were mutagenic following ten daily gavage doses or following administration in diet for 10 days. Neither chemical induced cell proliferation in the liver following repeat gavage administrations. In contrast, dietary administration of 6BT, and to a lesser extent of 5BT, induced hepatic cell proliferation. The carcinogen 6BT, but not the noncarcinogen 5BT, caused proliferation of oval stem cells in the livers by both routes of administration. It is possible that mutations induced in oval cells by 6BT are responsible for its potent carcinogenicity, and that the comparative absence of these cells in 5BT-treated livers may account for the carcinogenic inactivity of 5BT. Equally, the proliferation of the oval cells may reflect changes in liver homeostasis associated with the liver toxicity observed at the dose level of 6BT used (which was, nonetheless, the dose level used in the positive cancer bioassays). It is concluded that the new data presented cannot explain the differing carcinogenic activities of 5BT and 6BT, and that the reported noncarcinogen 5BT may also be carcinogenic when adequately assessed for this activity.

Animals↗

Variability in thermal response of primed and non-primed seeds of squirreltail [Elymus elymoides (Raf.) Swezey and Elymus multisetus (J. G. Smith) M. E. Jones].

Bottlebrush squirreltail [Elymus elymoides (Raf.) Swezey = Sitanion hystrix (Nutt.) J. G. Smith] and big squirrel-tail [Elymus multisetus (J. G. Smith) M. E. Jones = Sitanion jubatum (J. G. Smith)] have a broad geographical distribution and have been identified as high priority species for restoration of degraded rangelands in the western United States. These rangelands exhibit high annual and seasonal variability in seedbed microclimate. The objective of this study was to examine variability in thermal response of both primed and non-primed seeds of these species in the context of field-variable temperature regimes. Seed priming treatments were selected to optimize germination rate in a low-temperature test environment. Primed and non-primed seeds were evaluated for laboratory germination response under 12 constant temperature treatments between 3 and 36 degrees C. Thermal time and base temperature were estimated by regression analysis of germination rate as a function of temperature in the sub-optimal temperature range. The thermal germination model and 6 years of field temperature data were used to simulate the potential germination response under different field planting scenarios. Seed priming reduced the total germination percentage of some seedlots, especially at higher germination temperatures. Seed priming increased the germination rate (reduced the number of days to 50 % germination) by 3.8-8.4 d at 6 degrees C with a mean germination advancement of 6.9 +/- 0.6 d. Maximum germination advancement in the model simulations was 5-10 d for planting dates between I March and 15 May. Model simulations can be used to expand germination analysis beyond simple treatment comparisons, to include a probabilistic description of potential germination response under historical or potential future conditions of seedbed microclimate.

Germination↗

Experimental and natural infection of North American bats with West Nile virus.

Big brown (Eptesicus fuscus) and Mexican free-tailed (Tadarida brasiliensis) bats were inoculated with the New York 99 strain of West Nile virus to assess their potential to serve as amplifying hosts and determine the clinical effect of infection. Groups of three or four bats were bled at daily intervals between 1 and 6 days after inoculation to determine the pattern of viremia. Beginning 2 days after inoculation, virus was isolated each day from one or more E. fuscus bats, in titers ranging from 10 to 180 plaque-forming units per milliliter of serum. Virus was not isolated from any of the sera collected from T. brasiliensis bats. None of the bats from either species showed clinical signs associated with exposure to virus. Sera from an additional 149 bats collected in Louisiana in 2002 during an epizootic of West Nile fever were tested for antibodies to virus, and two were found to be positive. These data suggest that bats from these two widely distributed species are unlikely to serve as amplifying hosts for West Nile virus.

Animals↗

Development of a modified method for sequencing high G:C regions in chicken anemia virus genome.

Two areas in the chicken anemia virus (CAV) genome have high G:C content with secondary structures. These two G:C rich areas could not be sequenced with Perkin Elmer's Big Dye Terminator Cycle Sequencing Kit. Several modifications were carried out to solve the problem. Finally, a package of modified method was developed to sequence the high G:C areas. The result showed that the Perkin Elmer's Big Dye Terminator Cycle Sequencing Kit with the normal procedures are not suitable for sequencing the high G:C regions of the CAV genome. The present developed method made the Perkin Elmer's Kit useful for the first time to sequence the G:C rich hairpin structures of the CAV genome. The system may be useful to sequence all other G:C rich DNA templates.

Animals↗

[Innovative technologies in the complex treatment of patients with rheumatoid arthritis].

The treatment of rheumatoid arthritis (RA) remains a difficult task since the current therapy does not always result in the disease remission. The search for and development of new methods and principles for the complex therapy of RA have been underway. 144 RA patients aged 22 to 65, disease duration--72.4 +/- 7.3 months, have been investigated. A majority of them (62.3%) had stage 2 RA, and 77.4% had RA stages 2-3. The patients who were taking methotrixate for 5 years were found to respond better and longer to the traditional-therapy drugs versus drugs of other basic groups. An intensification of treatment (by methilprednizolone combined with cyclophosphamide) in a group of stage 1 RA patients) improperly responding to the therapy (resulted in a disease remission for as long as 2.5 months. An intensification of therapy in stage 2 RA (by cyclophosphamide, vincristin and prednizolone) entailed a 13.2-month remission in 23 patients. A big number of contraindications restrict the use of such intense therapy which should be replaced, in such cases, by anticytokine drugs. Remission and improvements were ensured after remicade in 4 and 2 of 7 RA patients respectively. DMARS provided a significantly lower RA intensity that lasted, however, only for 2 weeks, which necessitates further research related with higher drug's doses and with extending its effect. Stem-cells transplantations were used in RA, after which remission and improvements were observed in 80% of patients.

Adult↗

Role of the BMK1/ERK5 signaling pathway: lessons from knockout mice.

Mitogen-activated protein (MAP) kinase cascades play a central role in mediating extracellular stimuli-induced intracellular signaling during cell activation. The fourth and least studied mammalian MAP kinase pathway, big MAP kinase 1 (BMK1), also known as extracellular signal regulated kinase 5 (ERK5), is activated in response to growth factors and stress. Activation of this signaling pathway has been implicated not only in physiological functions such as cell survival, proliferation and differentiation but also in pathological processes such as carcinogenesis, cardiac hypertrophy and atherosclerosis. In recent years a series of gene-targeted mice lacking components within the BMK1 cascade have been generated, which have enabled us to investigate the role of the BMK1 pathway within different tissues. Analyses of these knockout mice have led to major discoveries in the role of BMK1 signaling in angiogenesis and in cardiac development. Moreover, studies using conditional BMK1 knockout mice, which circumvent the early embryonic lethality of BMK1 knockouts, have unveiled the importance of BMK1 in endothelial survival and maintenance of vascular integrity during adulthood. Here we summarize current understanding of the function of BMK1, as well as include new data generated from a series of tissue-specific BMK1 knockout mice in an attempt to dissect the role of the BMK1 pathway in various cell types in animals.

Animals↗

Early experience with employee choice of consumer-directed health plans and satisfaction with enrollment.

OBJECTIVE: To assess the initial impact of offering consumer-defined health plan (CDHP) options on employees. DATA SOURCES/STUDY SETTING: A mail survey of 4,680 employees in the corporate offices of Humana Inc. in June 2001. STUDY DESIGN: The study was a cross-sectional mail survey of employees aged 18 and older who were eligible for health care benefits. The survey was conducted following open enrollment. The primary outcome is the choice of consumer-directed health plan or not; the secondary outcome is satisfaction with the enrollment process. Important covariates include sociodemographic characteristics (age, gender, race, educational level, exempt or nonexempt status, type of coverage), health status, health care utilization, and plan design preferences. DATA COLLECTION METHODS: A six-page questionnaire was mailed to the home of each employee, followed by a reminder postcard and two subsequent mailings to nonrespondents. PRINCIPAL FINDINGS: The response rate was 66.2 percent. Seven percent selected one of the two new plan options. Because there were no meaningful differences between employees choosing either of the two new options, these groups were combined in multivariate analysis. A logistic regression modeled the likelihood of choosing the novel plan options. Those selecting the new plans were less likely to be black (odds ratio [OR] 0.46), less likely to have only Humana coverage (OR 0.30), and more likely to have single coverage (OR 1.77). They were less likely to have a chronic health problem (OR 0.56) and more likely to have had no recent medical visits (OR 3.21). They were more likely to believe that lowest premiums were the most important plan attribute (OR 2.89) and to think there were big differences in the premiums of available plans (OR 5.19). Employees in fair or poor health were more likely to have a difficult time during the online enrollment process. They were more likely to find the communications very helpful (OR 0.42) and the benefits information very understandable (OR 0.38). They were less likely to feel that they had enough time to make their enrollment decision (OR 0.47). CONCLUSIONS: Employees who were attracted to the new CDHP plan options valued the attributes that distinguished these plans from other choices. The shift to consumer-defined plans and to the electronic provision of information, however, requires a significant increase in the communication support for all employees, but particularly for those in fair or poor health whose information needs are the most complex and individualized.

Adult↗

One-step processing of the amphibian vasotocin precursor: structure of a frog (Rana esculenta) "big" neurophysin.

Vasotocin-associated neurophysin (MSEL-neurophysin) from the frog Rana esculenta has been isolated and sequenced through tryptic and staphylococcal proteinase peptides and cyanogen bromide fragments. This protein appears homologous to the mammalian vasopressin-associated neurophysin with a C-terminal glycopeptide extension homologous to the mammalian copeptin. In contrast to the two-step processing of mammalian vasopressin/MSEL-neurophysin/copeptin precursor, a single cleavage is therefore involved in the processing of the amphibian vasotocin/neurophysin precursor. It appears that the physiological release of the vasopressin-like hormone from the N-terminal end of the protein precursor is not dependent upon a previous trimming of the C-terminal copeptin-like moiety.

Amino Acid Sequence↗

[Laboratory animal anaesthesia: influence of anaesthetic protocols on experimental models].

The use of experimental animals requires anaesthesia to provide immobility and analgesia. Animals require anaesthesia not only for ethical reasons but also because pain and stress can alter the quality of research results. Recognition of pain, and its treatment is important throughout the procedure. Before anaesthesia, animals are acclimated and rehydrated. Except in small rodents and in ruminants, in order to avoid vomiting, a fast of 8 to 12 hours before anaesthesia is recommended. In order to protect animals against suffering and distress during transfer, restraint and management, a premedication is administered. Most human anaesthetic products can be used in animals. There are some specific veterinary anaesthetics. Moreover, the anaesthetic effects could be different from specie to an other. In most big animals, induction is realized by intravenous administration. In small rodents, venous puncture and contention could be difficult, and anaesthetic agents may be injected via intraperitoneal or intramuscular way. The principal inconvenient of these administration routes is the impossibility to adjust dose to animal response. In large animals, human anaesthesia material can be used. Some technical adaptations could be necessary in smaller animals. In rodents or in neonatology, specific devices are recommended. ECG, arterial pressure, tidal volume, expired CO(2) and oxygen saturation monitoring assess quality of, and tolerance to anaesthesia. If animals are awaked after anaesthesia, postoperative management is closed to human clinical problems. During animal experimentations, anaesthesia may interact with results. All anaesthetic drugs alter normal physiology in some way and may confound physiologic results. In the literature, most publications do not mention this possible interaction. Investigators need to understand how animals are affected by anaesthetic drugs in order to formulate anaesthetic protocols with minimal effects on data. Extrapolation between different animal species and human and animals about the effects of anaesthetic agents are very hazardous. Great differences exist between the effects observed in vitro and in whole animals. The effects of the anaesthetics could be totally different if they are used alone or in association. The same anaesthetic could have opposite effects from an organ to another. For results validation, the anaesthesia side effects (hypoventilation, hypotension, cooling em leader ) have to be minimized. All new experimental models should require discussing the possible interferences between anaesthesia and results and to compare results obtained with different anaesthetic protocols.

Anesthesia↗

Contamination of diverse nifH and nifH-like DNA into commercial PCR primers.

False-positive results due to DNA contamination in PCR reagents have become a big problem in the amplification of small amounts of DNA. Recently, it was revealed that PCR reagents were contaminated with the nifH (dinitrogenase reductase) gene. We found that the PCR primers supplied by some manufacturers contained nifH gene and nifH-like DNA. This contamination resulted in false-positive results when searching for nifH genes in environmental samples. The sequences of the contaminating DNA appeared to be widely varied in the phylogenetic analysis of nifH. For this reason, great care should be taken when analyzing trace amounts of nucleotides.

DNA↗

What is the impact of commercial test preparation courses on medical examination performance?

BACKGROUND: Commercial test preparation courses are part of the fabric of U.S. medical education. They are also big business with 2,000 sales for 1 firm listed at nearly $250 million. This article systematically reviews and evaluates research published in peer-reviewed journals and in the "grey literature" that addresses the impact of commercial test preparation courses on standardized, undergraduate medical examinations. SUMMARY: Thirteen computerized English language databases were searched using 29 search terms and search concepts from their onset to October 1, 2002. Also manually searched was medical education conference proceedings and publications after the end date; and medical education journal editors were contacted about articles accepted for publication, but not yet in print, that were deemed pertinent to this review. Studies that met three criteria were selected: (a) a commercial test preparation course or service was an educational intervention, (b) the outcome variable was one of several standardized medical examinations, and (c) results are published in a peer-reviewed journal or another outlet that insures scholarly scrutiny. The criteria were applied and data extracted by consensus of 2 reviewers. The search identified 11 empirical studies, of which 10 (8 journal articles, 2 unpublished reports) are included in this review. Qualitative data synthesis and tabular presentation of research methods and outcomes are used. CONCLUSION: The articles and unpublished reports reveal that current research lacks control and rigor; the incremental validity of the commercial courses on medical examination performance, if any, is extremely small; and evidence in support of the courses is weak or nonexistent; almost no details are given about the form and conduct of the commercial test preparation courses; studies are confined to courses in preparation for the Medical College Admission Test, the former National Board of Medical Examiners Part 1, and the United States Medical Licensing Examination Step 1, not tests of clinical science; and that cost-benefit analyses of the test preparation courses have not been done. It is concluded that the utility and value of commercial test preparation courses in medicine have not been demonstrated, and that evaluation apprehension in the medical profession and aggressive marketing practices are most likely responsible for commercial course prosperity.

Advertising↗

Serum cholesterol and triglyceride distribution in 7767 school-aged Greek children.

OBJECTIVE: To elucidate associations of age and sex with serum cholesterol and triglyceride levels and to provide for the first time percentile distribution data for pediatric lipids. PARTICIPANTS AND METHODS: A high sample of 7767 (3980 boys, 3787 girls) fasting schoolchildren, 6 to 14 years of age, were studied in Athens, Greece. RESULTS: The mean cholesterol ranged from 157 to 174 mg/dL for boys and from 158 to 172 mg/dL for girls peaking at 9 years of age for both sexes. Triglyceride levels also tended to increase gradually and to peak at 11 years of age for both sexes. The high-density lipoprotein cholesterol levels were highest at 9 years of age for both sexes and the low-density lipoprotein cholesterol levels also tended to peak at 9 years of age for boys and at 8 years of age for girls. Atherogenic indices ranged from 1.54 to 1.68 for boys and 1. 51 to 1.85 for girls. CONCLUSION: According to these findings, it could be suggested that diet changes in the Greek population, especially in children and adolescents, living in big cities is significantly influencing their total cholesterol profiles throughout the last 10 years.

Child↗

[Spinal instrumentation, source of progress, but also revealing pitfalls].

The second half of the XXo century and especially the last 30 years have been the source of a great improvement for surgical treatment of spinal pathology essentially in 3 directions:--First, for the patient himself and his comfort by suppression for most of the cases of any post operative external support thanks to the rigidity, security and strength of segmental fixation given by the hooks, screws and rods systems, as well for posterior as anterior instrumentation. In addition, these new techniques allow the patient to return quickly to standing and walking activity and subsequently the surgery for adult people increased dramatically especially for all kind of degenerative diseases and more and more extended spinal deformities.--The second major improvement came from the real and new understanding of the 3 dimensions for all the physiology and pathology of the spine leading to practical applications for the design and surgical strategies for correction. The exploding expansion of the era of computer technology brought a lot of help in such understanding as well as for the development of spinal instrumentation.--Finally the impressive development of medical imaging with CT scan and less and less invasive techniques like MRI allow a much better vision of spinal cord and roots (a major concern for the spinal surgeon). All this occurs also because simultaneous revolution occurred in the field of anesthesia and intensive care especially post operatively, but also because the big progress for monitoring of vital function as well as neurological monitoring during surgery. The consequence of that was an improvement for the results concerning the patient for functional quality of life as well as for cosmesis. The subsequent failures resulting of these improvements came from various fields even if we exclude infection or neurological complications more and more controlled now.--At the level of the indications because of these lack of post operative external immobilization, indication for cosmesis extend widely including adults. But also because these adult peoples are asking more and more for an active way of life including often sports. The indications for function also extend requiring more and more pre operative checking to limit the increase of the risk.--At the level of the pre operative strategy, most surgeons were establishing the strategy looking only on more or less close similar cases already done. In fact no personalized strategy done on biomechanical static and dynamic data of the patient as well as its connective and bone tissue proper qualities were really performed. It is why it is still now difficult to know pre operatively the behavior of the not fused area above and mainly below the instrumented area. Because the power of correction was very much improved with the new instruments, we can get some 3D imbalance immediately after or secondary acquired after such surgery as well from anterior or posterior devices. It is why we need pre operative simulation of surgery thanks to the computer.--At the level of surgery itself: it is not entered in the practical field any per operative 3D reliable measurement to know exactly the surgeon is doing because the maximum of reduction is not the optimum for many cases and this has to be quantified. The last thing is of course the difficulty to translate the lying position of the patient during surgery to the standing functional one. Some answers or perspectives for the future may come from:--The real pre operative simulation of the surgery (including levels of instrumentation amount of correction in 3D) according to the personalized values, stiffness, quality of soft tissues, weight, size, of the patient, localization and type of the deformity, etc.... Computer software already exists or are on the way to be expanded.--Per operative 3D control of what is doing the surgeon are also emerging with real time information in order to adjust the correction according to the pre op. simulation. In addition the noticed improvements on the biological field for fusion with bone activators like BMP, Hydroxyapatite, or bone substitutes like bio-active ceramics will probably help for fusion and decrease necessity of bone grafting. It is the same about disc regeneration which is on the way. Finally it is evident that the first steps already done for spinal surgery avoiding fusion will extend.--For children and growing spine, the challenge is major, but with memory metal instruments, laser precise destruction of abnormal growing structures as well as posterior flexible instrumentation avoiding stripping of the periosteum and leaving integrity of the disc and facet joints function, improvements are also on the way.--For adult and degenerative spinal deformities and pain, the development of spinal arthroplasty already done for the disc replacement will improve as well as for the posterior joints units where artificial ligaments experience will be replaced by real artificial joints still on experiment. In conclusion, some general biological medical questions are still waiting for answers:--Neurology and erect posture--Growth and degeneration--Malignancy (comprehension and control)--Pain and suffering. And of course what is the fact of the genetics for all of these problems: plenty of work for the future.

Adolescent↗

Changes in exercise performance and hormonal concentrations over a big ten soccer season in starters and nonstarters.

As a consequence of the physiological demands experienced during a competitive soccer season, the antagonistic relationship between anabolic and catabolic processes can affect performance. Twenty-five male collegiate soccer players were studied throughout a season (11 weeks) to investigate the effects of long-term training and competition. Subjects were grouped as starters (S; n = 11) and nonstarters (NS; n = 14). Measures of physical performance, body composition, and hormonal concentrations (testosterone [T] and cortisol [C]) were assessed preseason (T1) and 5 times throughout the season (T2-T6). Starters and NS participated in 83.06% and 16.95% of total game time, respectively. Nonstarters had a significant increase (+1.6%) in body fat at T6 compared to T1. Isokinetic strength of the knee extensors (1.05 rad.sec(-1)) significantly decreased in both S (-12%) and NS (-10%; p < or = 0.05) at T6. Significant decrements in sprint speed (+4.3%) and vertical jump (-13.8%) were found at T5 in S only. Though within normal ranges (10.4-41.6 nmol.L(-1)), concentrations of T at T1 were low for both groups, but increased significantly by T6. Concentrations of C were elevated in both groups, with concentrations at the high end of the normal range (normal range 138-635 nmol.L(-1)) at T1 and T4 in NS and T4 in S, with both groups remaining elevated at T6. Data indicate that players entering the season with low circulating concentrations of T and elevated levels of C can experience reductions in performance during a season, with performance decrements exacerbated in starters over nonstarters. Soccer players should therefore have a planned program of conditioning that does not result in an acute overtraining phenomenon prior to preseason (e.g., young players trying to get in shape quickly in the 6 to 8 weeks in the summer prior to reporting for preseason camp). The detrimental effects of inappropriate training do not appear to be unloaded during the season and catabolic activities can predominate.

Adult↗