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1.
Ann Surg Oncol ; 31(2): 735-743, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37952018

RESUMEN

BACKGROUND: Intraperitoneal chemotherapy is promising for gastric cancer with peritoneal metastasis. Although a phase III study failed to show a statistically significant superiority of intraperitoneal paclitaxel combined with S-1 and intravenous paclitaxel, the sensitivity analysis suggested clinical efficacy. Thus, attempts to combine intraperitoneal paclitaxel with other systemic therapies with higher efficacy have been warranted. We sought to explore the efficacy of intraperitoneal paclitaxel with S-1 and cisplatin. PATIENTS AND METHODS: Gastric cancer patients with peritoneal metastasis were enrolled in the phase II trial. In addition to the established S-1 and cisplatin regimen every 5 weeks, intraperitoneal paclitaxel was administered on days 1, 8, and 22 at a dose of 20 mg/m2. The primary endpoint was overall survival rate at 1 year after treatment initiation. Secondary endpoints were progression-free survival and toxicity. RESULTS: Fifty-three patients were enrolled and fully evaluated for efficacy and toxicity. The 1-year overall survival rate was 73.6% (95% confidence interval 59.5-83.4%), and the primary endpoint was met. The median survival time was 19.4 months (95% confidence interval, 16.1-24.6 months). The 1-year progression-free survival rate was 49.6% (95% confidence interval, 34.6-62.9%). The incidences of grade 3/4 hematological and non-hematological toxicities were 43% and 47%, respectively. The frequent grade 3/4 toxicities included neutropenia (25%), anemia (30%), diarrhea (13%), and anorexia (17%). Intraperitoneal catheter and implanted port-related complications were observed in four patients. There was one treatment-related death. CONCLUSIONS: Intraperitoneal paclitaxel combined with S-1 and cisplatin is well tolerated and active in gastric cancer patients with peritoneal metastasis.


Asunto(s)
Neoplasias Peritoneales , Neoplasias Gástricas , Humanos , Cisplatino , Neoplasias Gástricas/patología , Paclitaxel , Neoplasias Peritoneales/secundario , Protocolos de Quimioterapia Combinada Antineoplásica
2.
Int J Clin Oncol ; 29(2): 179-187, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38078975

RESUMEN

BACKGROUND: Colon perforation caused by colorectal cancer (CRC) is a fatal condition requiring emergency intervention. For patients with metastatic lesions, surgeons face difficult decisions regarding whether to resect the primary and metastatic lesions. Moreover, there is currently no established treatment strategy for these patients. This study aimed to investigate the clinical practice and long-term outcomes of patients with metastatic CRC diagnosed with the onset of colon perforation. METHODS: We performed a population-based multicenter cohort study. Consecutive patients diagnosed with stage IV CRC between 2008 and 2015 at all designated cancer hospitals in Fukushima Prefecture, Japan, were enrolled in this study. We evaluated the impact of colon perforation on the survival outcomes of patients with metastatic CRC. The main outcome was the adjusted hazard ratio (aHR) of perforation for overall survival (OS). Survival time and HRs were estimated using Kaplan‒Meier and Cox proportional regression analyses. RESULTS: A total of 1258 patients were enrolled (perforation: n = 46; non-perforation: n = 1212). All but one of the patients with perforation underwent primary resection or colostomy and 25 cases were able to receive chemotherapy. The median OS for the perforation and non-perforation groups was 19.0 and 20.0 months, respectively (p = 0.96). Moreover, perforation was not an independent prognostic factor (aHR: 0.99; 95% confidence interval: 0.61-1.28). CONCLUSIONS: In metastatic CRC, perforation is not necessarily a poor prognostic factor. Patients with perforation who undergo primary tumor resection or colostomy and prompt initiation of systemic chemotherapy might be expected to have a survival time similar to that of patients with non-perforated colon.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Neoplasias del Recto , Humanos , Pronóstico , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/cirugía , Neoplasias Colorrectales/tratamiento farmacológico , Estudios de Cohortes , Estudios Retrospectivos , Neoplasias del Colon/patología
3.
Int J Biometeorol ; 68(7): 1303-1314, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38598168

RESUMEN

Associations of exertional heat exhaustion (EHE)-related symptoms with lifestyle habits and health factors specific to female athletes, ranked by relative risks from high to low, remain elusive. Addressing this issue would benefit athletes and coaches, ensuring safer practices during summer sports activities. To address this issue, we distributed paper-based questionnaires to seven universities in Japan, and 983 respondents completed our survey. The questionnaires covered various personal characteristics, lifestyle habits, perceived health factors, perceived athletic activity, and EHE-related symptoms. In this retrospective case-control study, we analyzed the relationships of EHE-related symptoms (objective variables) with lifestyle habits, health factors, and athletic activity conditions (explanatory variables) using the partial proportional odds model. The questionnaire responses revealed that perceived dehydration, sickness, loss of appetite, perceived accumulated fatigue, perceived mental stress, lack of ambient wind, and insufficient rest breaks were positively associated with EHE-related symptoms, with relative risks ranging from high to low. Using an air conditioner during sleep and having a sleep duration of ≥ 6 h were associated with a reduced risk of EHE-related symptoms. The study results suggest that female athletes should be allowed to postpone exercise or reduce its intensity and volume based on their perceptions of dehydration, sickness, loss of appetite, accumulated fatigue, and mental stress in summer to prevent heat-related illnesses.


Asunto(s)
Atletas , Agotamiento por Calor , Humanos , Femenino , Japón , Factores de Riesgo , Adulto Joven , Atletas/psicología , Universidades , Estudios Retrospectivos , Estudios de Casos y Controles , Encuestas y Cuestionarios , Adulto , Esfuerzo Físico , Estilo de Vida , Percepción
4.
Int J Biometeorol ; 67(4): 649-659, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36840761

RESUMEN

The purpose of this study was to investigate associations between lifestyle habits, health factors, athletic activity conditions, and exertional heat exhaustion (EHE)-related symptoms among male college athletes in Japan based on a self-completed questionnaire. The paper-based questionnaires were distributed to 11 universities in Japan, and 2006 respondents completed the survey. Data of personal characteristics (age, body mass), lifestyle habits (sleep duration, use of air-conditioner while sleeping, and practice duration), perceived health factors (loss of appetite, sleep deprivation, sickness, dehydration, accumulated fatigue, and mental stress), perceived athletic activity (insufficient rest breaks, high ambient temperature, excessive humidity, strong solar radiation, lack of ambient wind, and clothing discomfort), and EHE-related symptoms (dizziness, headaches, nausea, and malaise) were collected. The association between lifestyle habits, health factors, athletic activity conditions (explanatory variables), and EHE-related symptoms (objective variables) was analyzed using the partial-proportional odds model. "Perceived dehydration" (odds ratios [ORs] 1.70-2.31, p < 0.002)," "sickness" (ORs 1.35-1.76), p < 0.001), "perceived accumulated fatigue" (ORs 1.13-1.31, p ≤ 0.001), "perceived mental stress" (ORs 1.17-1.31, p < 0.019), "lack of ambient wind" (ORs 1.12-1.19, p < 0.022), "loss of appetite" (ORs 1.16-1.23, p < 0.037), and "sleep deprivation" (ORs 1.15-1.17, p < 0.025) were positively associated with EHE-related symptoms, whereas "using an air conditioner during sleeping" (ORs 0.91, p = 0.047) during summer seasons was negatively associated. These findings suggest that athletes should be allowed to postpone or downregulate exercise intensity and/or volume based on their perceptions of dehydration, sickness, accumulated fatigue, mental stress, loss of appetite, and/or sleep deprivation in the summer to prevent heat illness.


Asunto(s)
Agotamiento por Calor , Humanos , Masculino , Japón/epidemiología , Estudios de Casos y Controles , Deshidratación , Atletas , Fatiga/epidemiología , Factores de Riesgo
5.
J Surg Oncol ; 125(4): 615-620, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34985764

RESUMEN

BACKGROUND: The prognosis of gastric cancer patients with positive lavage cytology without gross peritoneal dissemination (P0CY1) is poor. The survival benefit of gastrectomy for these patients has not been established. PATIENTS AND METHODS: In this population-based cohort study, we investigated the impact of radical gastrectomy with lymph node dissection for P0CY1 patients. Patients who were diagnosed with Stage IV gastric cancer from 2008 to 2015 in all nine cancer-designated hospitals in a tertiary medical area were listed. Patients who were diagnosed with histologically proven adenocarcinoma in both the primary lesion and lavage cytology during the operation or a diagnostic laparoscopic examination were enrolled. Patients with a gross peritoneal lesion or other metastatic lesions were excluded. The primary outcome was the adjusted hazard ratio (aHR) of gastrectomy for overall survival. We also evaluated the survival time in patients who underwent gastrectomy or chemotherapy in comparison to patients managed without primary surgery or with best supportive care. RESULTS: One hundred patients were enrolled. The aHR (95% confidence interval) of gastrectomy was 0.677 (0.411-1.114, p = 0.125). The median survival time in patients who received gastrectomy (n = 74) was 21.7, while that in patients managed without primary surgery (n = 30) was 20.5 months (p = 0.155). The median survival time in patients who received chemotherapy (n = 76) was 23.0 months, while that in patients managed without chemotherapy was 8.6 months (p < 0.001). CONCLUSION: Gastrectomy was not effective for improving the survival time in patients with P0CY1 gastric cancer. Surgeons should prioritize the performance of chemotherapy over surgery as the initial treatment.


Asunto(s)
Citodiagnóstico/métodos , Gastrectomía/mortalidad , Laparoscopía/mortalidad , Escisión del Ganglio Linfático/mortalidad , Lavado Peritoneal/métodos , Neoplasias Peritoneales/mortalidad , Neoplasias Gástricas/mortalidad , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Peritoneales/secundario , Neoplasias Peritoneales/cirugía , Pronóstico , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Tasa de Supervivencia
6.
Jpn J Clin Oncol ; 51(11): 1601-1607, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34491361

RESUMEN

OBJECTIVE: The prognosis of patients with liver metastases from gastric cancer is determined using tumor size and number of metastases; this is similar to the factors used for the prediction of liver metastases from colorectal cancer. The relationship between the degree of liver metastasis from gastric cancer and prognosis with reference to the classification of liver metastasis from colorectal cancer was investigated. METHODS: This was a multi-institutional historical cohort study. Among patients with stage IV gastric cancer, who visited the cancer hospitals in Fukushima Prefecture, Japan, between 2008 and 2015, those with simultaneous liver metastasis were included. Abdominal pretreatment computed tomography images were reviewed and classified into H1 (four or less liver metastases with a maximum diameter of ≤5 cm); H2 (other than H1 and H3) or H3 (five or more liver metastases with a maximum diameter of ≥5 cm). The hazard ratio for overall survival according to the H grade (H1, H2 and H3) was calculated using the Cox proportional hazards model. RESULTS: A total of 412 patients were analyzed. Patients with H1, H2 and H3 grades were 118, 162 and 141, respectively, and their median survival time was 10.2, 5.7 and 3.1 months, respectively (log-rank P < 0.001). The adjusted hazard ratio for overall survival was H1: H2: H3 = reference: 1.39 (95% confidence interval: 1.04-1.85): 1.69 (95% confidence interval: 1.27-2.27). CONCLUSIONS: The grading system proposed in this study was a simple and easy-to-use prognosis prediction index for patients with liver metastasis from gastric cancer.


Asunto(s)
Neoplasias Hepáticas , Neoplasias Gástricas , Estudios de Cohortes , Humanos , Neoplasias Hepáticas/patología , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Neoplasias Gástricas/patología , Tasa de Supervivencia
7.
Int J Clin Oncol ; 26(7): 1248-1256, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34089402

RESUMEN

BACKGROUND: It remains unclear whether intensive chemotherapy for Stage IV colorectal cancer (CRC) patients aged 80 years or older is beneficial prognostically. This study aimed to investigate the overall survival of Stage IV CRC patients aged ≥ 80 years receiving intensive chemotherapy. METHODS: The study design was a population-based, multicenter, historical cohort study. The extracted participants' data were consecutive patients diagnosed as Stage IV CRC between January 2008 and May 2015 in nine hospitals in Japan. Patients were classified into two groups according to age: aged group (≥ 80 years) and younger group (< 80 years old). Intensive chemotherapy was defined as at least two courses of doublet chemotherapy with oxaliplatin-or irinotecan-based regimens. The primary outcome was the adjusted hazard ratio (HR) of age ≥ 80 years in patients who undergoing intensive chemotherapy. RESULTS: During the study period, 1259 patients were treated for Stage IV CRC in the participating hospitals. In total, 231 patients (18.3%) were in the aged group, and 1028 (81.7%) were in the younger group, and 788 (62.6%) underwent intensive chemotherapy. The median overall survival for the aged and younger group patients was 21.0 months (interquartile range (IQR), 10.6-34.1 months) and 24.3 months (IQR 12.6-39.3 months), respectively. The adjusted HR of age ≥ 80 years was 1.29 (confidence intervals 0.84-2.00). CONCLUSION: Stage IV CRC patients aged 80 years or older receiving intensive chemotherapy had a similar prognosis to those aged < 80 years. Avoiding intensive chemotherapy for mCRC patients simply because they are ≥ 80 years old is not recommended.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Colorrectales , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estudios de Cohortes , Neoplasias Colorrectales/tratamiento farmacológico , Fluorouracilo/uso terapéutico , Humanos , Japón , Oxaliplatino/uso terapéutico
8.
J Strength Cond Res ; 35(3): 782-790, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30161087

RESUMEN

ABSTRACT: Inoue, K, Yamashita, N, Kume, M, and Yoshida, T. Differences in the repeated sprint performance between the first and latter halves of trials under conditions of several thermal states in exercising muscles. J Strength Cond Res 35(3): 782-790, 2021-The purpose of this study was to determine whether the effects of thermal states in exercising muscle on repeated sprint cycling (RSC) performance differ between the first and latter half of trials. Nine male subjects performed 8 × 8 seconds of RSC with a 40-second rest period. The subjects wore water-perfused trousers with water at 6° C (COLD), 17° C (COOL), 30° C (WARM), or 44° C (HOT). During the first half of trials, the peak power output (PPO), mean power output (MPO), and sum of work output (SWO) were significantly (p < 0.05) greater under the WARM and HOT conditions than under the COLD and COOL conditions, and a difference in the PPO and MPO between WARM and HOT was noted in the second sprint bout during the first half of the exercise. However, during the latter half of trials, there was no significant difference in the PPO, MPO, and SWO among the 4 conditions. The tympanic temperature (Tty) was significantly elevated under the HOT condition but fell under the COLD and COOL conditions, whereas the Tty under the WARM condition did not change significantly (p < 0.05) during the experiment. The total sweat loss was significantly (p < 0.05) greater in the HOT condition than in the other conditions. These results suggest that the effect of thermal states in exercising muscle on the RSC performance is greater in the first half of exercise than in the latter half, possibly because of the elevation of the core temperature and sweat loss under HOT conditions.


Asunto(s)
Ejercicio Físico , Sudoración , Calor , Humanos , Masculino , Músculos , Descanso
10.
Ecotoxicol Environ Saf ; 143: 38-45, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28499129

RESUMEN

Antimicrobial resistant bacteria are widespread in aquatic environments. The aim of the present study was to obtain information on the occurrence of bacteria with antimicrobial resistance and their multiple antimicrobial resistance (MAR) patterns in a river basin in Japan. In addition, the occurrence of fecal bacteria producing extended-spectrum beta-lactamases (ESBLs) and metallo-beta-lactamase (MBL) in the aquatic environment was determined. Among the Escherichia coli isolates recovered from river samples upstream, 55% isolates were resistant to at least one antimicrobial and 18% were MAR. Among the E. coli isolates recovered from wastewater treatment plant (WWTP) effluent samples, 74% isolates were resistant to at least one antimicrobial and 46% were MAR. These findings suggest that the presence of WWTP effluent will increase the degree of contamination with MAR in the aquatic environment. Among the ampicillin-resistant isolates recovered from river samples, 21% isolates were judged as ESBL-producing and none (0%) was judged as MBL-producing. Among the ampicillin-resistant isolates recovered from WWTP effluent samples, 21% were judged as ESBL-producing and 1% was judged as MBL-producing. As for the hospital wastewater samples, 48% were judged as ESBL-producing and 3% were judged as MBL-producing. The percentage of ESBLs and MBL production was highest in hospital wastewater samples. All of the ESBL-producing isolates detected had resistance to ampicillin, cephazolin, and cefpodoxime and many ESBL-producers had resistance not only to beta-lactams but also to other kinds of antimicrobials such as aminoglycosides and quinolones. The frequency of detection of MBL-producers was much lower than that of ESBL-producers and MBL-producers were not detected in the river samples. However, the detection in WWTP effluent samples indicated that bacteria with MBL were present downstream of the WWTP at low concentrations. Thus, ESBLs and MBL have already been spread around aquatic environments.


Asunto(s)
Antibacterianos/toxicidad , Farmacorresistencia Bacteriana Múltiple , Escherichia coli/efectos de los fármacos , Ríos/microbiología , Contaminantes Químicos del Agua/toxicidad , beta-Lactamasas/metabolismo , Escherichia coli/enzimología , Escherichia coli/aislamiento & purificación , Heces/microbiología , Japón , Pruebas de Sensibilidad Microbiana , Ríos/química , Aguas Residuales/química , Aguas Residuales/microbiología
11.
Environ Monit Assess ; 189(9): 442, 2017 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-28791526

RESUMEN

The objective of this work was to evaluate the biological effect of the secondary effluent (SE) of a wastewater treatment plant and reclaimed water treated via ultrafiltration (UF) followed by either reverse osmosis (RO) membrane filtration or nanofiltration (NF) to be used for environmental use by comparing the results of algal growth inhibition tests of concentrated samples of the SE and permeates of RO and NF with those of six rivers in southern Okinawa Island. Although the SE water had no adverse effects on the growth of the algae Pseudokirchneriella subcapitata, it could lead to water quality degradation of rivers in terms of its toxic unit value, whereas the use of RO and NF permeates would not lead to such degradation. The recharge of rivers, into which domestic wastewater and livestock effluents might be discharged in southern Okinawa Island, with reclaimed water subjected to advanced treatment could dilute the concentrations of chemicals that cause biological effects and improve the water quality of the rivers, based on the results of the bioassay using P. subcapitata. Comparing the results of bioassays of reclaimed water with those of the ambient water at a site might be effective in assessing the water quality of reclaimed water for environmental use at the site.


Asunto(s)
Monitoreo del Ambiente , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis , Filtración/métodos , Ríos/química , Ultrafiltración , Aguas Residuales , Purificación del Agua/métodos , Calidad del Agua/normas
12.
Appl Environ Microbiol ; 82(14): 4244-4252, 2016 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-27208125

RESUMEN

UNLABELLED: F-specific RNA phages (FRNAPHs) are considered potential viral indicators of water pollution due to their occurrence and stability in water environments. However, their suitability as viral indicators is not fully elucidated because the characteristics of FRNAPHs are variable depending on the genotype. In this study, for the characterization of infectious FRNAPH genotypes, integrated culture reverse transcription-PCR coupled with the most probable number approach was applied to surface water samples. Further, to recover low concentrations of FRNAPH genotypes, an FRNAPH recovery method was developed. The novel FRNAPH recovery method using a noncharged microfiltration membrane could effectively recover FRNAPH strains without inactivation, while a method using an electronegative microfiltration membrane resulted in the inactivation of some strains. Infectious FRNAPH genotypes in surface water samples were successfully quantified with an efficiency comparable to that of the conventional plaque assay. Genotype I (GI) and GII FRNAPHs tended to be predominant at locations impacted by treated and untreated municipal wastewater, respectively. The numbers and proportions of infectious FRNAPHs tended to be higher during the winter season when water temperature decreased. IMPORTANCE: Properties of FRNAPHs are highly variable depending on their genotypes. Previous typing methods for FRNAPHs are not quantitative and/or are based on molecular assays, which cannot differentiate infective strains from inactive strains. Due to the reasons mentioned above, the utility of FRNAPHs as viral indicators of water pollution has not been fully validated. In this study, a quantitative genotyping method for infectious FRNAPHs was developed and applied to surface water samples. The method enabled characterization of infectious FRNAPH genotypes in terms of their occurrence and seasonality. Moreover, comparison of the method to a conventional molecular assay (reverse transcription-quantitative PCR) enabled characterization of their stability. Our approach can provide novel findings for further validation of FRNAPHs as viral indicators of water pollution.


Asunto(s)
Genotipo , Fagos ARN/clasificación , Fagos ARN/aislamiento & purificación , Carga Viral/métodos , Microbiología del Agua , Fagos ARN/genética , Estaciones del Año
13.
Environ Sci Technol ; 49(10): 6319-26, 2015 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-25902010

RESUMEN

The in vitro estrogen receptor (ER) reporter gene assay has long been used to measure estrogenic activity in wastewater. In a previous study, we demonstrated that the assay represents net estrogenic activity in the balance between estrogenic and antiestrogenic activities in wastewater. However, it remained unclear whether the net estrogenic activity measured by the in vitro ERα reporter gene assay can predict the in vivo estrogenic effect of wastewater. To determine this, we measured the following: estrogenic and antiestrogenic activities of wastewater and reclaimed water by the in vitro ERα reporter gene assay, expression of vitellogenin-1 (vtg1) and choriogenin-H (chgH) in male medaka (Oryzias latipes) by quantitative real-time PCR, and estrone, 17ß-estradiol, estriol, and 17α-ethynylestradiol concentrations chemically to predict estrogenic activity. The net estrogenic activity measured by the in vitro medaka ERα reporter gene assay predicted the in vivo vtg1/chgH expression in male medaka more accurately than the concentrations of estrogens. These results also mean that in vivo vtg1/chgH expression in male medaka is determined by the balance between estrogenic and antiestrogenic activities. The in vitro medaka ERα reporter gene assay also predicted in vivo vtg1/chgH expression on male medaka better than the human ERα reporter gene assay.


Asunto(s)
Bioensayo/métodos , Receptor alfa de Estrógeno/análisis , Estrógenos/toxicidad , Expresión Génica/efectos de los fármacos , Vitelogeninas/análisis , Contaminantes Químicos del Agua/toxicidad , Animales , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Estrógenos/análisis , Estrógenos/química , Masculino , Oryzias , Vitelogeninas/metabolismo , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química
14.
J Sports Sci ; 33(9): 892-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25555077

RESUMEN

Outdoor exercise often proceeds in rainy conditions. However, the cooling effects of rain on human physiological responses have not been systematically studied in hot conditions. The present study determined physiological and metabolic responses using a climatic chamber that can precisely simulate hot, rainy conditions. Eleven healthy men ran on a treadmill at an intensity of 70% VO2max for 30 min in the climatic chamber at an ambient temperature of 33°C in the presence (RAIN) or absence (CON) of 30 mm · h(-1) of precipitation and a headwind equal to the running velocity of 3.15 ± 0.19 m · s(-1). Oesophageal temperature, mean skin temperature, heart rate, rating of perceived exertion, blood parameters, volume of expired air and sweat loss were measured. Oesophageal and mean skin temperatures were significantly lower from 5 to 30 min, and heart rate was significantly lower from 20 to 30 min in RAIN than in CON (P < 0.05 for all). Plasma lactate and epinephrine concentrations (30 min) and sweat loss were significantly lower (P < 0.05) in RAIN compared with CON. Rain appears to influence physiological and metabolic responses to exercise in heat such that heat-induced strain might be reduced.


Asunto(s)
Regulación de la Temperatura Corporal , Calor , Lluvia , Carrera/fisiología , Temperatura Cutánea , Glucemia/metabolismo , Epinefrina/sangre , Esófago/fisiología , Ácidos Grasos no Esterificados/sangre , Frecuencia Cardíaca , Humanos , Ácido Láctico/sangre , Masculino , Norepinefrina/sangre , Percepción , Esfuerzo Físico , Sudoración , Triglicéridos/sangre , Adulto Joven
15.
J Strength Cond Res ; 29(1): 116-25, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25532431

RESUMEN

The level of hypohydration at which power output during intermittent exercise performance starts to decrease is not fully understood. The purpose of this study was to investigate the effects of 2% hypohydration without hyperthermia on intermittent exercise performance. Eight collegiate amateur boxers completed 2 exercise tests. On day 1, subjects hypohydrated by 2% of body mass by exercising in a hot environment, and on day 2, subjects performed intermittent exercise (4 × 2 minute per round [R] separated by 1-minute recovery) under a randomly assigned condition of with (HYP) or without (EUH) hypohydration. Each bout consisted of 8 × 5 seconds of maximal cycling exercise (0.05 kp × body mass) separated by 10 seconds of passive recovery. Mean power output per kilogram (MPO), total power output per kilogram (TPO), energy system relative contribution, and core rectal temperature (Tre) were measured. Changes in body mass before the exercise tests were -2.25 ± 0.18% (HYP) and -0.17 ± 0.19% (EUH) (p < 0.001). Mean power output, TPO, and each energy contribution ratio were not significantly different between the trials, and pre- and postexercise test Tre did not differ significantly between trials. Results demonstrated that approximately 2% hypohydration lies below the point at which power output during intermittent exercise starts to decline.


Asunto(s)
Boxeo/fisiología , Deshidratación/fisiopatología , Ejercicio Físico/fisiología , Calor/efectos adversos , Umbral Anaerobio , Temperatura Corporal , Prueba de Esfuerzo , Fiebre , Humanos , Masculino , Distribución Aleatoria , Adulto Joven
16.
Environ Sci Technol ; 48(11): 6366-73, 2014 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-24802743

RESUMEN

Endocrine-disrupting chemicals are exogenous substances that alter the function of the endocrine system, with adverse health effects on organisms or their progeny. In vitro estrogen receptor (ER) reporter gene assays have long been used to measure estrogenic activity in wastewater. Nevertheless, there is still uncertainty about their usefulness in environmental monitoring on account of a discrepancy between the estrogenic response of the in vitro assay and concentrations of estrogenic compounds determined by chemical analysis. Here, we measured estrogenic and antiestrogenic activities in wastewater by ERα reporter gene assay. All samples were simultaneously analyzed for estrone, 17ß-estradiol, estriol, and 17α-ethynylestradiol, and the concentrations were used to predict estrogenic activity. All samples in which measured estrogenic activity was significantly lower than predicted showed strong antiestrogenic activity. In addition, we confirmed that the fraction that did not have antiestrogenic activity showed stronger estrogenic activity than the unfractionated wastewater extract. These results indicate that antiestrogenic compounds in wastewater suppress the activity of natural estrogens, and the reporter gene assay represents the net activity.


Asunto(s)
Disruptores Endocrinos/toxicidad , Congéneres del Estradiol/toxicidad , Antagonistas de Estrógenos/toxicidad , Receptor alfa de Estrógeno/genética , Aguas Residuales/química , Contaminantes Químicos del Agua/toxicidad , Animales , Disruptores Endocrinos/análisis , Monitoreo del Ambiente/métodos , Congéneres del Estradiol/análisis , Antagonistas de Estrógenos/análisis , Células HEK293 , Humanos , Oryzias , Contaminantes Químicos del Agua/análisis
17.
Artículo en Inglés | MEDLINE | ID: mdl-38953763

RESUMEN

BACKGROUND: Cooling devices reduce thermal strain during pre-, between-, and postexercise. However, their efficacy during moderate/intensity runs in hot conditions with airflow equivalent to the running speed remains unclear. This study assessed physiological and perceptual responses to neck and upper back fan-cooling through an air-perfused rucksack under such conditions. METHODS: Ten young men ran at 60% V̇O2peak for 30 min in 35 °C, 50% relative humidity with (FAN) and without (CON) air-perfused rucksacks with a hood in a randomized order. Headwind equal to running speed was provided in both conditions. The fan-cooling trial consisted of upper back and neck fan cooling with airflow at 4-5 m/s via two fans attached on either side of the rucksack. Rectal and skin temperatures, whole-body thermal sensation, thermal comfort, and changes in body mass were measured. RESULTS: Upper back skin temperature and thermal sensation were significantly lower throughout the exercise in the FAN than in the CON, whereas thermal comfort was significantly higher at 15-40 min in the FAN (all P≤0.05). Heart rate elevation during 30 min of running was attenuated in the FAN compared to that in the CON (P≤0.05). No significant differences in rectal and mean skin temperatures, or total body mass loss were observed between the two trials. CONCLUSIONS: These results indicate that additional fan-cooling on the upper back and neck during running in uncompensable hot conditions with a headwind had limited physiological benefits. However, whole-body-based thermal sensation and comfort are partially improved with the use of an air-perfused rucksack.

18.
J Sports Med Phys Fitness ; 64(8): 749-757, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38602034

RESUMEN

BACKGROUND: Jumping and linear sprinting performances show a moderate correlation with change of direction (COD) ability. However, the extent of these correlations remains unknown through statistical analysis. Thus, this study statistically compared correlation coefficients between COD, COD deficit (CODD), and jumping and linear sprint performances. METHODS: National-level basketball (29) and baseball (18) intercollegiate female athletes performed 20-m linear sprint, proagility (5-10-5) test, squat jump (SJ), countermovement jump with (CMJarm) and without (CMJ) arm swing and modified reactive strength index (RSImod). Correlation analysis was used to assess factors correlated with COD performance and CODD; subsequently, correlation coefficient comparison test was used to determine better correlations with COD and CODD performance. RESULTS: CMJ (r=-0.483) and CMJarm (r=-0.446) had stronger correlations with 10-m COD (both, P<0.018) than with 10-m linear sprint (r=0.431, P=0.002). For 20-m COD, RSImod, CMJ, and CMJarm (r=-0.491--0.543, P<0.001) better correlated with 20-m COD than with 20-m linear sprints (r=0.436, P=0.002), while RSI (both r=-0.317, P<0.030) and SJ (r=-0.359, r=-0.293, P=0.046) were weakly correlated with 10- and 20-m COD. The differences in correlation coefficients for RSImod, CMJ, and CMJarm were not significant in both 10- and 20-m COD. Ten-meter linear sprint performance only correlated with 10-m CODD, while no correlation was observed with 20-m CODD. CONCLUSIONS: Stronger correlations of RSImod, CMJ, and CMJarm with 10-/20-m COD than with linear sprinting, RSI, and SJ suggest that training focused on improving countermovement and arm swings with jumping may enhance COD performance in female athletes.


Asunto(s)
Rendimiento Atlético , Béisbol , Baloncesto , Prueba de Esfuerzo , Carrera , Humanos , Femenino , Rendimiento Atlético/fisiología , Baloncesto/fisiología , Adulto Joven , Carrera/fisiología , Béisbol/fisiología , Prueba de Esfuerzo/métodos , Brazo/fisiología , Fuerza Muscular/fisiología
19.
Artículo en Inglés | MEDLINE | ID: mdl-38867667

RESUMEN

Revisiting classical experiments on the impact of air resistance on metabolic rate, we aimed to overcome limitations of previous research, notably: low participant numbers (n=1-3), highly turbulent wind, and confounding effects of rising body temperature. In a custom-built wind tunnel with reduced turbulence, 14 participants (8 males, 6 females) walked (5 km.h-1) and ran on a treadmill (70%V̇O2max) at 0, 2, 4 and 6 m.s-1 headwind or tailwind in a counterbalanced design, with rest-breaks between each exposure to avoid rises in body core temperature. Oxygen consumption (V̇O2) exhibited strong linear relationships versus wind direction, dynamic pressure and air speed squared(Vwr2), lower in magnitude for headwind than tailwind. A moderate linear relationship was observed between heart rate, wind direction, dynamic pressure and Vwr2. Below 4 m⸱s-1, the effect of wind was well within inter- and intra-individual variation and equipment uncertainty, and only at wind speeds ≥4 m⸱s-1 did the differences in physiological responses reach statistical significance. Our data indicate that at running speeds below 4 m⸱s-1 (14.4 km/h), indoor treadmill and outdoor running are comparable in terms of the metabolic impact of air movement relative to the person. However, this does not extend to the thermoregulatory effect of wind, with outdoor running providing a higher cooling rate due to the self-generated wind created during running. By removing the confounding impact of core temperature rises, the observed effects of headwind were lower and those of tailwind larger than observed previously. In the context of middle-distance running, headwind created by running at 21.5 km.h-1 would result in a 2.2% increase of V̇O2. A relative tailwind of the same speed would lead to a 3.1% reduction.

20.
Water Res ; 253: 121197, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38341968

RESUMEN

The membrane bioreactor (MBR) process always offers better wastewater treatment than conventional activated sludge (CAS) treatment. However, the difference in their efficacy of virus reduction remains unknown. To investigate this, we monitored virus concentrations before and after MBR and CAS processes over 2 years. Concentrations of norovirus genotypes I and II (NoV GI and GII), aichivirus (AiV), F-specific RNA phage genotypes I, II, and III (GI-, GII-, and GIII-FRNAPHs), and pepper mild mottle virus (PMMoV) were measured by a quantitative polymerase chain reaction (qPCR) method at two municipal wastewater treatment plants (WWTPs A and B) in Japan. Virus concentration datasets containing left-censored data were estimated by using both maximum likelihood estimation (MLE) and robust regression on order statistics (rROS) approaches. PMMoV was the most prevalent at both WWTPs, with median concentrations of 7.5 to 8.8 log10 copies/L before treatment. Log10 removal values (LRVs) of all viruses based on means and standard deviations of concentrations before and after treatment were consistently higher following MBR than following CAS. We used NoV GII as a model pathogen in a quantitative microbial risk assessment of the treated water, and we estimated the additional reductions required following MBR and CAS processes to meet the guideline of 10-6 DALYs pppy for safe wastewater reuse.


Asunto(s)
Virus , Purificación del Agua , Aguas del Alcantarillado , Aguas Residuales , Reactores Biológicos , Purificación del Agua/métodos , Eliminación de Residuos Líquidos/métodos
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