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2.
Artigo em Inglês | MEDLINE | ID: mdl-32437531

RESUMO

BACKGROUND: Encapsulating peritoneal sclerosis (EPS) is an uncommon but life-threatening complication of peritoneal dialysis (PD) therapy. The causative factors of EPS remain unclear. Pathological studies of the peritoneum affected by EPS and relationships with clinical factors including PD solutions remain lacking. The objective of this study was to examine peritoneal samples from EPS patients and to identify the associations of peritoneal pathology with different clinical factors. METHODS: Peritoneal specimens were obtained at the time of surgical enterolysis in Tsuchiya General Hospital from 1993 to 2016. A total of 223 PD patients were enrolled and analyzed. Tissues were fixed with formalin and processed with hematoxylin and eosin and Masson's trichrome staining, as well as immunohistochemical staining for CD31 and CD68. RESULTS: Evaluations could be made in 174 patients who received surgical enterolysis. Conventional or pH-neutral low-glucose degradation product PD solutions were utilized during PD treatment. The conventional PD solution group showed less angiogenesis (P = 0.013) but more severe vasculopathy, in the form of a lower ratio of luminal diameter to vessel diameter (L/V ratio) (P < 0.001) in association with longer PD treatment. Multivariate Cox proportional hazard models revealed that L/V ratio (per 0.1 increase, hazard ratio = 0.88, 95% confidence interval 0.77-0.99, P = 0.047) was significantly associated with a lower incidence of EPS relapse. In contrast, most of the cases in the pH-neutral solution group showed milder vasculopathy. CONCLUSIONS: The pathology of EPS differed between conventional and pH-neutral solution groups. Vasculopathy was related to the development and relapse of EPS in the conventional solution group.

3.
Intern Med ; 59(5): 683-687, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32115518

RESUMO

A 45-year-old man with idiopathic aplastic anemia required renal replacement therapy (RRT) due to end-stage renal disease (ESRD). We succeeded in inserting the peritoneal dialysis (PD) catheter under cover of frequent red blood cell and platelet infusions because of severe pancytopenia. During the one-year period after starting PD using an ultraviolet-ray sterilization device, he developed severe leukopenia but no PD-related peritonitis or exit site/tunnel infection until he died of pneumonia. This case suggests that PD might be a suitable choice as RRT in ESRD patients with aplastic anemia, even in those with severe pancytopenia.

4.
Tokai J Exp Clin Med ; 45(1): 18-23, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32219805

RESUMO

A 61-year-old female was diagnosed with multiple endocrine neoplasia type 2A (MEN2A), caused by a heterozygous point mutation in the RET gene (TGC to TAC at codon 634) resulting in the substitution of cytosine with leucine (C634Y). The patient had pheochromocytoma (PCC) in the left adrenal gland and medullary thyroid carcinoma (MTC) with liver metastasis. Primary hyperparathyroidism (PHP) was not evident. Family history data suggested that the RET gene mutation was inherited from the father. The PCC was removed laparoscopically, but the MTC was observed conservatively for 7 years because the status of the MTC was compatible with T1N1M1 and stage IVC; therefore, it was not curable with surgery. The MTC liver metastasis increased in size. Lenvatinib, an oral multi-tyrosine kinase inhibitor, was administered until the patient had received a total dose of 1336mg, and then administration was stopped because of nausea. The reduction rate of the MTC liver metastasis was 31%, which was considered partial response. At this point, the patient was doing well, suggesting that lenvatinib was effective in treating the MTC liver metastasis and may be one of the treatment for advanced MTC caused by C634Y mutation in the RET gene.

5.
High Alt Med Biol ; 21(2): 160-166, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32013568

RESUMO

Background: Osteogenic responses induced by training under hypoxia remain unclear. We aimed to investigate whether intermittent hypoxic resistance training affects osteogenic responses. Materials and Methods: Sixteen male participants underwent resistance training under normoxia (NRT; n = 7) or hypoxia (HRT; O2 = 14.4%, n = 9), twice a week for 8 weeks. The HRT group exercised and rested for 30 minutes under hypoxia, with total hypoxic exposure time in one session of ∼60 minutes. At pre- and postexperiment, bone mineral density (BMD) of the whole body and right proximal femur was measured. At the first and last training sessions, bone alkaline phosphatase (BAP), osteocalcin (OC), cross-linked N-telopeptide of type I collagen (NTx), type I collagen cross-linked C-telopeptide (ICTP), interleukin-6 (IL-6), and blood lactate (La) concentration were analyzed at rest and postexercise. Results: BMD did not change with training and hypoxia. Although BAP, OC, and ICTP levels at rest significantly increased with training (p < 0.01, 0.05, and 0.05, respectively), they did not change with hypoxia. NTx and IL-6 did not change. Additionally, changing patterns of bone markers and La induced by a single bout of exercise were similar among groups in both training sessions. Conclusions: Short-term resistance training enhanced overall bone metabolism, regardless of the oxygen level. Hypoxia has no effects on osteogenic responses.

6.
World Neurosurg ; 137: e526-e534, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32061954

RESUMO

OBJECTIVE: Sarcopenia is defined as the loss of skeletal muscle mass and is considered an important factor for clinical outcomes in various diseases. Recent studies have shown that temporal muscle thickness (TMT) and area (TMA) can be novel indicators of sarcopenia. We examined clinical characteristics, including TMT and TMA, of patients with subarachnoid hemorrhage (SAH) treated by endovascular coiling. METHODS: A retrospective analysis of 298 patients with SAH who were treated with endovascular coiling from 2009 to 2019 was conducted. Their premorbid modified Rankin Scale (mRS) score was 0-2. The association between the factors and Hunt and Kosnik (H-K) grades on admission and that between the clinical variables and mRS scores 6 months after the operation were analyzed. RESULTS: In all 298 patients with SAH, Fisher group 4 and TMA <200 mm2 were independently associated with H-K grade III-V on admission in the multivariate analysis. In 254 patients with H-K grades I-III on admission, age, H-K grade III, presence of ventriculoperitoneal shunt, presence of postoperative complications, and TMA <200 mm2 were independent factors related to poor outcomes in the multivariate analysis. CONCLUSIONS: The H-K grade on admission was independently associated with TMA. The mRS score 6 months after aneurysm treatment in patients with H-K grades I-III was also independently associated with TMA. Sarcopenia could be one of a few modifiable factors that prevent severe symptoms of SAH and improve outcomes after coiling by strengthened nutrition and physical activity.

7.
Appl Physiol Nutr Metab ; : 1-6, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32049562

RESUMO

This study aimed to elucidate changes in diaphragm and accessory inspiratory muscle (sternocleidomastoid (SCM) muscle and intercostal muscle (IC)) function after a 6-week training program. Nineteen male elite collegiate swimmers were assigned to either a control group (n = 9) or training group (n = 10). The subjects in the training group performed 30 maximum inspirations at a load resistance of 50% of maximum inspiratory mouth pressure (PImax) using an inspiratory muscle training device. These were conducted twice per day and 6 days per week. At baseline and after 6 weeks, PImax, shear modulus of the diaphragm, and electromyograms (EMG) of the SCM and IC during a maximal inspiratory maneuver were evaluated. Relative change in PImax was greater in the training group than in controls. The shear modulus during a PImax maneuver had increased significantly in both groups after 6 weeks. EMG amplitudes of the SCM increased in the training group after 6 weeks, but not in the control group. EMG amplitudes of the IC did not change after 6 weeks in either group. These results suggest that 6-week inspiratory resistive training significantly improves the activation of the SCM, which could be one of the major mechanisms behind increases in inspiratory muscle strength after resistive training. Novelty Six-week inspiratory resistive training increased diaphragm stiffness during maximal inspiration maneuver. Six-week inspiratory resistive training increased electromyogram amplitudes of the sternocleidomastoid during maximal inspiration maneuver.

8.
Muscle Nerve ; 61(5): 653-656, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32052453

RESUMO

INTRODUCTION: Assessment of sensory impairment in diabetic patients by pain threshold test using intraepidermal electrical stimulation (IES) is a recently developed technique. However, there are no normative pain thresholds in healthy people. METHODS: We examined pain, vibration, and pressure thresholds in 178 healthy subjects using IES, vibration perception testing (VPT), and Semmes-Weinstein monofilament testing (SWMT). RESULTS: The mean values for each age group for pain threshold ranged from 0.07 to 0.12 mA. Pain thresholds were unaffected by age. As the age increased, VPT values decreased from 18.0 to 10.6 seconds and SWMT values increased from 21.4 to 45.3 g/mm2 . There were no significant differences in pain threshold, VPT, and SWMT between men and women. DISCUSSION: The pain threshold test appears to be useful for diabetic neuropathy screening because normative values are not affected by age.

9.
Microbes Infect ; 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31972245

RESUMO

We examined activities of dense granule proteins (GRAs), which Toxoplasma gondii secretes within infected cells, to stimulate microglial IFN-γ production in vitro. We identified that the N-terminal region (amino acids 41-152) of GRA6 (GRA6Nt) stimulates IFN-γ production by both a microglia cell line and primary microglia purified from the brains of uninfected adult mice. In contrast, neither of GRA1, GRA2, GRA5Nt, nor the carboxyl-terminal (amino acids 174-224) of GRA6 stimulated microglial IFN-γ production. GRA6Nt appears to be a target molecule of the sentinel function of microglia to detect cerebral proliferation of T. gondii and activate their IFN-γ production for facilitating the protective immunity to control the pathogen.

10.
Parasitol Int ; 76: 102030, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31778800

RESUMO

Toxoplasma gondii takes two different life cycle stages within intermediate hosts including humans. Tachyzoites proliferate during the acute stage, and they transform into cysts to establish a chronic infection preferentially in the brain. IFN-γ production by infiltrated CD4+ and CD8+ T cells is required for the prevention of cerebral tachyzoite growth. IFN-γ production by brain-resident cells, most likely microglia, plays a key first line defense role to facilitate both innate and T cell-mediated protective immunity to control the tachyzoite growth. IFN-γ produced by brain-resident cells activates cerebral expression of IFN-dependent effector molecules to suppress tachyzoite growth during the early stage of infection. Their IFN-γ production also induces an expression of CXCL9 and CXCL10 chemokines to recruit immune T cells into the brain, and upregulates cerebral expression of MHC class I and II molecules for antigen presentation to the recruited T cells to activate their IFN-γ production. CD8+ T cells also have the activity to remove T. gondii cysts from the brains of infected hosts. Of interest, the anti-cyst activity of CD8+ T cells does not require their IFN-γ but does require perforin. Notably, we discovered that CD8+ cytotoxic T cells penetrate in the cysts in a perforin-mediated manner, which induces morphological deterioration and destruction of the cysts and an accumulation of microglia and macrophages for their elimination. Thus, the immune system employs two distinct effector mechanisms mediated by IFN-γ or perforin depending on two different life cycle stages of a single pathogen, T. gondii, to control its cerebral infection.

11.
Arch Physiol Biochem ; : 1-5, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31686532

RESUMO

Context: Resistance exercise training has recently been considered as an effective type of training to increase energy metabolism and insulin sensitivity. However, mechanisms of the resistance training-induced improvements in energy metabolism and insulin sensitivity have not been fully understood. Zinc-α2-glycoprotein (ZAG), which is a novel adipokine, has beneficial effects on energy metabolism and insulin sensitivity.Objective: We investigated the effect of a single bout of resistance exercise on the ZAG concentration.Methods: Nine healthy men were enrolled. They performed a single bout of resistance exercise (bench press and leg press) consisting of 10 repetitions of five sets at 70% of maximum strength with 90-s rests in between sets. Blood samples were obtained before and after acute resistance exercise to measure the ZAG concentration.Results: The serum ZAG concentration significantly increased following acute resistance exercise.Conclusion: This result suggests that a single bout of resistance exercise may enhance the ZAG concentration.

12.
Nucl Med Commun ; 40(11): 1187-1192, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31568269

RESUMO

Asymmetric motor symptoms and the contralateral side of dopaminergic deficits are commonly observed in patients with Parkinson's disease. The laterality of the specific binding ratio (SBR) for dopamine transporter single-photon emission computed tomography may be useful for estimation of reduced dopamine transporter density in striatum of patients with Parkinson's disease. SBR with Southampton method (S-SBR) is widely used to evaluate in our country, but the results occasionally contradict with that of motor symptoms or visual evaluation in clinical practice, thus preventing a confident diagnosis. We reported dopamine transporter evaluation with distance-weighted histogram (DWH). We hypothesized that the SBR calculated using DWH (DWH-SBR) may also be useful to evaluate the laterality. The purpose of this study was to investigate the laterality of the SBR versus the asymmetry of motor symptoms, and versus visual evaluation. In total, 100 adult patients with Parkinson's disease were enrolled in our study. The symptom-affected side, the visual-affected side, and the lower SBR side were evaluated. The evaluation was performed in a blinded manner. Correlations between the Hoehn and Yahr scale (HY scale) and both the SBRs were also investigated. Concordance of lower DWH-SBR side for visual-affected side was significantly higher (99.0%) than it of lower S-SBR side (86.0%, P < 0.01). The HY scale was significantly related to both lower S-SBR and DWH-SBR (P < 0.01). The DWH method might minimize the disagreement of laterality between the SBR and visual evaluation, and be useful for making a confident diagnosis in patients with Parkinson's disease.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Doença de Parkinson/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único
13.
Sci Rep ; 9(1): 12719, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481684

RESUMO

Genetically modified nonhuman primates (NHP) are useful models for biomedical research. Gene editing technologies have enabled production of target-gene knock-out (KO) NHP models. Target-gene-KO/knock-in (KI) efficiency of CRISPR/Cas9 has not been extensively investigated in marmosets. In this study, optimum conditions for target gene modification efficacies of CRISPR/mRNA and CRISPR/nuclease in marmoset embryos were examined. CRISPR/nuclease was more effective than CRISPR/mRNA in avoiding mosaic genetic alteration. Furthermore, optimal conditions to generate KI marmoset embryos were investigated using CRISPR/Cas9 and 2 different lengths (36 nt and 100 nt) each of a sense or anti-sense single-strand oligonucleotide (ssODN). KIs were observed when CRISPR/nuclease and 36 nt sense or anti-sense ssODNs were injected into embryos. All embryos exhibited mosaic mutations with KI and KO, or imprecise KI, of c-kit. Although further improvement of KI strategies is required, these results indicated that CRISPR/Cas9 may be utilized to produce KO/KI marmosets via gene editing.

14.
J Antibiot (Tokyo) ; 72(12): 943-955, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31413314

RESUMO

We screened for bacterial phospho-N-acetylmuramyl-pentapeptide-translocase (MraY: EC 2.7.8.13) inhibitors with the aim of discovering novel antibiotics and observed inhibitory activity in the culture broth of an actinomycete, SANK 60501. The active compounds, muraminomicins A, B, C, D, E1, E2, F, G, H, and I exhibited strong inhibitory activity against MraY with IC50 values of 0.0105, 0.0068, 0.0104, 0.0099, 0.0115, 0.0109, 0.0089, 0.0134, 0.0186, and 0.0094 µg ml-1, respectively. Although muraminomicin F exhibited favorable antibacterial activity against drug-resistant Gram-positive bacteria, this activity was reduced with the addition of serum. To efficiently supply the core component for chemical modification studies, production was carried out in a controlled trial by adding myristic acid to the medium, and a purification method suitable for large-scale production was successfully developed.


Assuntos
Actinomycetales/metabolismo , Antibacterianos/química , Antibacterianos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Actinomycetales/genética , Antibacterianos/biossíntese , Proteínas de Bactérias/antagonistas & inibidores , Ácidos Graxos/química , Fermentação , Bactérias Gram-Positivas/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Transferases/antagonistas & inibidores
15.
Sci Rep ; 9(1): 12175, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31434958

RESUMO

Lymphatic absorption in the peritoneal cavity may contribute to ultrafiltration failure in peritoneal dialysis (PD). Lymphatic vessels develop during PD-related peritoneal fibrosis. Connective tissue growth factor (CTGF, also called CCN2) is an important determinant of fibrotic tissue remodeling, but little is known about its possible involvement in lymphangiogenesis. In this study, we investigated the relationship between CTGF and peritoneal lymphangiogenesis. A positive correlation was observed between vascular endothelial growth factor-C (VEGF-C), a major lymphangiogenic growth factor, and the CTGF concentration in human PD effluents. CTGF expression was positively correlated with expression of lymphatic markers and VEGF-C in human peritoneal biopsies. We found a positive correlation between the increase in CTGF and the increase in VEGF-C in cultured human peritoneal mesothelial cells (HPMCs) treated with transforming growth factor-ß1 (TGF-ß1). The diaphragm is a central player in peritoneal lymphatic absorption. CTGF expression was also correlated with expression of VEGF-C and lymphatics in a rat diaphragmatic fibrosis model induced by chlorhexidine gluconate (CG). Furthermore, CTGF gene deletion reduced VEGF-C expression and peritoneal lymphangiogenesis in the mouse CG model. Inhibition of CTGF also reduced VEGF-C upregulation in HPMCs treated with TGF-ß1. Our results suggest a close relationship between CTGF and PD-associated lymphangiogenesis.

16.
Surg Case Rep ; 5(1): 123, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31367855

RESUMO

BACKGROUND: Immunoglobulin (Ig) G4-related sclerosing disease is a pathological concept proposed in Japan during the early 2000s. This lesion-forming disease may exhibit characteristics of a systemic disease but often affects a single organ. To date, IgG4-related sclerosing disease in the mammary gland, or IgG4-related mastitis (IgG4-RM), has rarely been reported. CASE PRESENTATION: Here, we describe the case of a female patient who was admitted to our hospital with the main complaints of left breast and axillary lymphadenopathy. A careful diagnostic imaging examination led to an initial suspicion of breast cancer. However, a needle biopsy led to a diagnosis of IgG4-RM. Subsequently, the patient was successfully treated with predonin. CONCLUSIONS: The treatment requirements for breast cancer and IgG4-RM differ considerably. This is a good example of a case wherein unnecessary surgical treatment, which is indicated for breast cancer, was avoided by needle biopsy. Accordingly, the patient was appropriately treated with steroids following a correct diagnosis.

17.
Am J Pathol ; 189(8): 1594-1607, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31301754

RESUMO

CD8+ cytotoxic T cells kill target cells through direct cell-cell contact. However, it remains unclear how these T cells eliminate a target of large mass. We investigated how CD8+ T cells remove tissue cysts of Toxoplasma gondii, which can grow to the size of >50 µm in diameter within infected cells. Notably, immunohistologic analyses in the brains of infected mice visualized the presence of numbers of CD8+ immune T cells that had migrated halfway through the cyst wall as well as T cells located fully within the cysts. Perforin was required for their invasion and cyst elimination. Cysts invaded by the T cells displayed morphologic deterioration and destruction. Within these deteriorated cysts, granular structures intensely positive for granzyme B were detected in association with T. gondii bradyzoites. Furthermore, the bradyzoites within the destroyed cysts were located within accumulated ionized calcium binding adaptor molecule 1 (Iba1)-positive microglia and Ly6C+ macrophages, suggesting that these phagocytes had phagocytosed those organisms for their eradication. The present study uncovered a previously unappreciated capability of CD8+ cytotoxic T cells to penetrate into a large target, T. gondii cysts, for their elimination. This invasive capability of CD8+ cytotoxic T cells in collaboration with phagocytes appears to be a powerful effector mechanism that functions against not only T. gondii cysts but also other large targets, including solid cancers.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Cistos , Imunidade Celular , Toxoplasma/imunologia , Toxoplasmose , Animais , Linfócitos T CD8-Positivos/patologia , Cistos/imunologia , Cistos/parasitologia , Cistos/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Toxoplasmose/imunologia , Toxoplasmose/patologia
19.
Breast ; 47: 1-9, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31229857

RESUMO

BACKGROUND: It is important to determine whether anthracycline-containing regimens or taxane-containing regimens are more effective in individual patients. The present study compared the efficacy of six cycles of docetaxel and cyclophosphamide (TC6) with that of three cycles of 5-fluorouracil, epirubicin and cyclophosphamide followed by docetaxel (FEC-D) in Japanese patients with hormone receptor (HR)-negative breast cancer (BC) to identify subtypes requiring anthracycline treatment. METHODS: The study included 103 patients with operable HR-negative BC. Of these patients 53 received FEC-D and 50 received TC6. The primary endpoint was pathological complete response (pCR). The secondary endpoints were safety, breast-conserving surgery, disease-free survival (DFS) and overall survival (OS). The predictive factors for each regimen were evaluated. RESULTS: Of the 103 patients, 97 completed the study (FEC-D, 50 patients; TC6, 47 patients). The pCR rate was higher with FEC-D (36%) than with TC6 (25.5%); however, the difference was not significant (P = 0.265). TC6 was safer than FEC-D, as the adverse events with docetaxel in the FEC-D regimen were similar to those with the TC6 regimen. Among patients with basal BC, the pCR rate was significantly higher with FEC-D (42.9%) than with TC6 (13.6%; P = 0.033). Among patients with triple-negative breast cancer (TNBC), the DFS and OS were significantly better with FEC-D than with TC6 (P = 0.016 and P = 0.034, respectively). CONCLUSION: TC6 was not as effective as FEC-D for treating HR-negative BC, as TC6 was not sufficient to treat TNBC, particularly the basal subtype. Our findings suggest that anthracyclines are better treatment options than taxanes for basal BC.


Assuntos
Antraciclinas/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Docetaxel/uso terapêutico , Fluoruracila/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Ciclofosfamida/uso terapêutico , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Esquema de Medicação , Epirubicina/uso terapêutico , Feminino , Humanos , Japão , Estimativa de Kaplan-Meier , Mastectomia Segmentar/métodos , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Medição de Risco , Estatísticas não Paramétricas , Análise de Sobrevida , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/cirurgia
20.
Int J Sports Physiol Perform ; : 1-5, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31094259

RESUMO

PURPOSE: Increases in maximal oxygen uptake (V˙O2max) and running economy improve performance in long-distance runners. Nevertheless, long-distance runners require sprinting ability to win, especially in the final phase of competitions. The authors determined the relationships between performance and sprinting ability, as well as other abilities in elite long-distance runners. METHODS: The subjects were 12 elite long-distance runners. Mean official seasonal best times in 5000-m (5000 m-SB) and 10,000-m (10,000 m-SB) races within 1 year before or after the examination were 13:58.5 (0:18.7) and 28:37.9 (0:25.2) (mean [SD]), respectively. The authors measured 100-m and 400-m sprint times as the index of sprinting ability. They also measured V˙O2max and running economy (V˙O2 at 300 m·min-1 of running velocity). They used a single correlation analysis to assess relationships between 5000 m-SB or 10,000 m-SB and other elements. RESULTS: There were significant correlations between 5000 m-SB was significantly correlated with 100-m sprint time (13.3 [0.7] s; r = .68, P = .014), 400-m sprint time (56.6 [2.7] s; r = .69, P = .013), and running economy (55.5 [3.9] mL·kg-1·min-1; r = .59, P = .045). There were significant correlations between 10,000 m-SB and 100-m sprint time (r = .72, P = .009) and 400-m sprint time (r = .85, P < .001). However, there was no significant correlation between 5000 m-SB or 10,000 m-SB and V˙O2max (72.0 [3.8] mL·kg-1·min-1). CONCLUSIONS: The authors' data suggest that sprinting ability is an important indicator of performance in elite long-distance runners.

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