Associations of physical activity and sedentary time with psychological distress among Japan self-defense forces personnel dispatched overseas: a prospective cohort study.

Objectives: Physical inactivity and sedentary time can worsen mental health; however, their relationship remains elusive, and related evidence among workers with overseas assignments is limited. Therefore, this study aimed to investigate the relationship between changes in physical activity and sedentary time and explored the subsequent risk of psychological distress among Japan Self-Defense Forces personnel.

Methods: This prospective study enrolled male Japan Self-Defense Forces personnel dispatched to the Republic of Djibouti from May 2018 to June 2019.

Effect of hyperbaric exposure on cognitive performance: an investigation conducting numerical Stroop tasks during a simulated 440 m sea water saturation diving.

Background: Saturation diving (SD) is useful and safe in deep diving for long durations. Japan Maritime Self-Defense Force (JMSDF) Undersea Medical Center (UMC) maintained safely deep 45 ATA SDHowever, cognitive performance was reportedly impaired by hyperbaric exposure in over 31 atmosphere absolute (ATA) SD. This study investigated the effects of hyperbaric exposure during 45 ATA deep SD on expert divers' cognitive function using Stroop tasks, a useful method to examine cognitive function, especially in narrow spaces such as SD chambers.

The composition of the human fecal microbiota might be significantly associated with fecal SCFA levels under hyperbaric conditions.

The fecal microbiota and short-chain fatty acids (SCFAs) play important roles in the human body. This study examined how hyperbaric conditions affect the fecal microbiota and fecal SCFAs. Fecal samples were obtained from 12 divers at three points during deep-diving training (before the diving training, at 2.

Utility of Hyperbaric Oxygen Therapy for Acute Acoustic Trauma: 20 years' Experience at the Japan Maritime Self-Defense Force Undersea Medical Center.

 Acute acoustic trauma, which is a kind of sensorineural hearing loss, is caused by acoustic overstimulation. Hyperbaric oxygen therapy (HBOT) is reported to be effective against acute acoustic trauma.  We aimed to evaluate the efficacy of HBOT against acoustic hearing loss based on our 20 years of experience with such cases.

Effects of hyperbaric conditions on fecal microbiota.

We aimed to determine whether the composition of the fecal microbiota changes under hyperbaric conditions. In this study, we collected fecal samples from 6 healthy divers at three points during deep diving training (before, 2.1 MPa, end).

Up-Regulation of Antioxidant Proteins in the Plasma Proteome during Saturation Diving: Unique Coincidence under Hypobaric Hypoxia.

Saturation diving (SD) is one of the safest techniques for tolerating hyperbaric conditions for long durations. However, the changes in the human plasma protein profile that occur during SD are unknown. To identify differential protein expression during or after SD, 65 blood samples from 15 healthy Japanese men trained in SD were analyzed by two-dimensional fluorescence difference gel electrophoresis.

Supplementation of antioxidants prevents oxidative stress during a deep saturation dive.

Conflicting views exist at the present regarding the influences of a deep saturation dive on liver function in divers. Therefore, we first reevaluated whether a deep saturation dive (400 msw) induces a hepatic disturbance. As the result, plasma activities of both transaminases (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]) increased significantly, whereas cholinesterase (Ch-E) activity decreased markedly, being highly suggestive of liver dysfunction.

Preferential conditions for and possible mechanisms of induction of ischemic tolerance by repeated hyperbaric oxygenation in gerbil hippocampus.

Objective: We reported previously that repeated hyperbaric oxygenation (HBO) as pretreatment induced ischemic tolerance in the gerbil hippocampus. This study was conducted to determine the preferential conditions for induction of ischemic tolerance by HBO and the mechanism of this induction through immunohistochemical analysis of Bcl-2, Bax, and manganese superoxide dismutase expression.

Methods: Five-minute forebrain ischemia was produced in gerbils after pretreatment with 2 atmospheres absolute (ATA) HBO once every other day for one, three, or five sessions, 2 ATA hyperbaric air once every other day for five sessions, or 3 ATA HBO once daily for 10 sessions.

Decrease in platelet count during saturation diving.

Background: The change in platelet count (PC) occurring during saturation diving has rarely been discussed. We set out to clarify the details of this change in PC, and its relationship with: i) the storage depth and duration of the saturation dive, and ii) the presence of decompression bubbles.

Methods: In a total of 42 divers, the change in PC was measured in 8 simulated saturation dives (1992-1998) using a Deep Diving Simulator with decompression procedures based on the modified DUKE-GKSS schedule.

Delayed onset pulmonary barotrauma or decompression sickness? A case report of decompression-related disorder.

A-24-yr-old male professional diver began to complain of substernal pain 3 h after a controlled ascent from a dive of less than 40 ft of sea water (fsw). The diving master who supervised his dive and the physicians who examined him on presentation suspected pulmonary barotrauma rather than decompression sickness (DCS) because he had only descended to a depth of 32 fsw. Hyperbaric oxygen therapy (HBO) by U.

Chondrosarcomatous differentiation in metastatic deposit of serous papillary cystadenocarcinoma.

A rare case of serous papillary cystadenocarcinoma of the ovary showing chondrosarcomatous differentiation in a metastatic deposit late in the clinical course is reported. A 49-year-old female underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy for bilateral ovarian tumors. Histological diagnosis was serous papillary cystadenocarcinoma of both ovaries with lymph node metastasis.

[Tuberculosis in the crew of a submarine].

We report the apparent spread of mycobacterial tuberculosis among a submarine crew from a crew member with a low grade of infectivity. The air-conditioning system of submarines requires completely closed recirculation of ambient air. If a person with pulmonary tuberculosis were in a submarine, one would expect to find a high incidence of tuberculosis among others on the ship.

Probable lung injury by long-term exposure to oxygen close to 50 kilopascals.

To investigate the possibility of lung injury after long-term saturation dives where oxygen partial pressure was kept between 42 and 50 kPa, we measured lung volumes, diffusing capacity (DLCO/VA), and ethane production in the alveolar expirate on six divers who participated in a 1.1-MPa saturation dive (9 days of total dive time) and on another six divers in a 4.5-MPa saturation dive (29 days of total dive time).

Bubble formation and decompression sickness on direct ascent from shallow air saturation diving.

To find the minimum supersaturation pressure for detectable bubble formation and for contraction of decompression sickness (DCS), three shallow air saturation dives at the depth of 6 m, 7 m, and 8 m were performed. The ultrasonic M-mode method was used for detecting bubbles. The exposure period was 3 d for all dives.

Psychophysiologic changes in sleep during simulated 200-m heliox saturation dives.

The standard polysomnogram and questionnaire were measured from 4 subjects during 2 simulated 200-m heliox saturation dives. These measurements were performed for 1 precompression night, bottom nights, 4 or 5 nights during decompression, and 1 postdecompression night. Although the subjects reported a marked decrease in quantity and quality of sleep at the bottom, only a slight degree of sleep disturbance caused by frequent awakenings was found in polysomnograms.

Decrease in the single-breath diffusing capacity after saturation dives.

Before and after saturation dives, we measured lung volumes and diffusing capacity (DL(CO)/V(A] with a single-breath method on 12 divers (6 divers per dive) who participated in 300-msw saturation dives (total dive time of 15 days with P(O)2 = 0.42 atm abs) and on 6 divers who were engaged in a 320-msw saturation dive (6 days of bottom time with P(O)2 = 0.42 atm abs and 12 days of total decompression time with P(O)2 = 0.

M-mode ultrasonic detection of microbubbles following saturation diving: a case report and proposal for a new grading system.

An M-mode ultrasound system was used to obtain a reliable method for the evaluation of microbubbles caused by decompression. When the probe is focused in the outflow tract of the right ventricle it is easy to recognize a linear configuration of the echoes caused by the microbubbles. A quantitative study of microbubbles can be done by counting the number of linear echoes per second.

Decompression sickness with subsequent lymphatic manifestation following recompression treatment: a case report in a heavy drinker.

A case of decompression sickness is described in an uniformed diver who developed lymphatic manifestations after recompression treatment. No definite contributing factors to this rare disorder were established. A brief review of cutaneous lesions in decompression sickness is also presented.