Recent evidence indicates that human pulmonary tuberculous granulomas are hypoxic, and a related dormancy model has been established for Mycobacterium tuberculosis using liquid media in tightly sealed tubes. In the present study, we examined the growth capacity of various mycobacterial species on solid, egg-based media under oxygen-limited conditions. During primary anaerobic cultivation on an Ogawa egg-based medium, all of the inoculated mycobacterial strains persisted for 10 weeks without detectable colony formation on the surface of the medium. Because these anaerobic cultures were restored and possessed the capacity to grow within 3 weeks following transfer to microaerobic conditions (5% or 10% oxygen tension), it was evident that the organisms persisted in a non-replicative dormant state as seen with anaerobic cultures in liquid media. The colonies grown under microaerobic conditions were also capable of growth under anaerobic conditions. Anaerobic growth could be observed only when the microaerobically grown colonies were subcultured under anaerobic conditions, suggesting that preliminary adaptation to the environment under reduced oxygen tensions is an essential process to enable growth under anaerobic conditions. A similar mode of anaerobic growth on slants of an egg-based medium was also observed with clinical isolates of M. tuberculosis. All of the clones that were adapted to grow in the anaerobic environments retained their species-specific colonial morphologic features, while, among the biochemical characteristics tested, heat-stable catalase activity and niacin accumulation in the medium disappeared during adaptation to anaerobic growth. Based on these results, we conclude that egg-based media actively support the anaerobiosis of mycobacteria exhibiting either a non-replicative dormant state or anaerobic growth, both of which are associated with latency and reactivation of tuberculosis. It was also evident that the use of egg-based media would be of great advantage in the diagnostic characterization of the reactivated clones of mycobacteria.

View full abstract

8-Hydroxydeoxyguanosine (8-OH-dG) is the most extensively analyzed oxidative stress marker. Recently, 8-hydroxyguanine (free base: 8-OH-Gua) has been recognized as an oxidative stress marker. To verify the usefulness of 8-OH-Gua, the 8-OH-dG and 8-OH-Gua levels in the urine and the 8-OH-Gua levels in the serum of type 2 diabetic model animals, db/db mice, were measured as oxidative stress markers by a column switching HPLC-system coupled to an electrochemical detector. The urinary 8-OH-Gua and 8-OH-dG levels in db/db mice (7-26 weeks old) were significantly higher than those in control (db/m+) mice. The 8-OH-Gua levels in the serum of the db/db mice were also about 2-fold higher than those in the control mice at 26 weeks of age. In addition, the urinary levels of 8-OH-dG and 8-OH-Gua increased with age (9-26 weeks). A significant positive correlation was obtained between the 8-OH-dG and 8-OH-Gua levels in urine. Although no difference was observed in the 8-OH-dG levels in the liver and kidney DNA between the diabetic and control mice, these results suggested that urinary 8-OH-dG and free base 8-OH-Gua in urine or serum may be good biomarkers of oxidative stress.

View full abstract

In recent years, there has been increasing interest in the relevance of environmental pollution to childrenʼs health. We investigated whether the concentrations of heavy metals in meconium can be used for the assessmet of prenatal exposure in Japan. Our study subjects were newborns whose mothers were hospitalized for childbirth at Tokai University Hospital between November 2010 and March 2011. The target compounds of this study were lead (Pb), cadmium (Cd) and arsenic (As). Meconium samples collected from 102 newborns were analyzed using ICPMS. The median concentrations of Pb and As in the meconium were 0.71 ppb and 0.03 ppb, respectively. The median concentration of Cd was below the limit of quantification. These concentration values are much lower than those used in previous studies. Further study is needed to compare the concentrations of heavy metals in biological samples and to investigate the availability of meconium for the assessment of exposure to heavy metals during pregnancy.

View full abstract

Indoor nitrogen dioxide (NO₂) concentration is an important factor for personal exposure despite the wide distribution of its sources. Exposure to NO₂ may produce adverse health effects. The aims of this study were to characterize the indoor air quality of wayside shops using multiple NO₂ measurements, and to estimate the contribution of outdoor NO₂ sources such as vehicle emission to indoor air quality. Daily indoor and outdoor NO₂ concentrations were measured for 21 consecutive days in wayside shops (5 convenience stores, 5 coffee shops, and 5 restaurants). Contributions of outdoor NO₂ sources to indoor air quality were calculated with penetration factors and source strength factors by indoor mass balance model in winter and summer, respectively. Most wayside shops had significant differences in indoor and outdoor NO₂ concentrations both in winter and in summer. Indoor NO₂ concentrations in restaurants were twice more than those in convenience stores and coffee shops in winter. While outdoor NO₂ contributions in indoor convenience stores and coffee shops were dominant, indoor NO₂ contributions were dominant in restaurants. These could be explained that indoor NO₂ sources such as gas range and smoking mainly affect indoor concentrations comparing to outdoor sources such as vehicle emission. The indoor mass balance model by multiple measurements suggests that quantitative contribution of outdoor air on indoor air quality might be estimated without measurements of ventilation, indoor generation and decay rate.

View full abstract

Nitric oxide (NO) is synthesized by three distinct NO synthase (NOS) isoforms (neuronal, inducible, and endothelial NOS), all of which are expressed in the human heart. The roles of NOSs in the pathogenesis of heart failure have been described in pharmacological studies with NOS inhibitors. Recently, genetically engineered animals have been used. We have generated mice in which all 3 NOS isoforms are completely disrupted (triple n/i/eNOS^-/- mice). Morphological, echocardiographic, and hemodynamic analysis were performed in wild-type, singly nNOS^-/-, iNOS^-/-, eNOS^-/-, and triple n/i/eNOS^-/- mice. Importantly, significant left ventricular (LV) hypertrophy and diastolic dysfunction was noted only in n/i/eNOS^-/- mice, and those pathology was similar to diastolic heart failure in humans. Finally, treatment with an angiotensin II type 1 (AT1) receptor blocker, significantly prevented those abnormalities. These results provide the evidence that AT1 receptor pathway plays a center role in the pathogenesis of cardiac disorders in the n/i/eNOS^-/- mice. Our studies with triple n/i/eNOS^-/- mice provide pivotal insights into an understanding of the pathophysiology of NOSs in human heart failure.

View full abstract

The author reports the case of a 36 year old man with cervical cord injury in whom autonomic dysreflexia developed into intracerebral hemorrhage during inpatient rehabilitation. This patient showed complete quadriplegia (motor below C6 and sensory below C7) due to fracture of the 6th cervical vertebra. An indwelling urethral catheter had been inserted into the bladder for 3 months, diminishing bladder expansiveness. Bladder capacity decreased to 200 ml and the patient frequently experienced headaches whenever his bladder was full.To obtain smoother urine flow, a supra-pubic cystostomy was performed. The headaches were temporarily cured, but soon relapsed with extreme increases in blood pressure, representing typical symptoms of autonomic dysreflexia. However, no potential triggers were identified or removed, and lack of blood pressure management led to left putaminal hemorrhage. Despite operative treatment, the right upper extremity showed progressive increases in muscle tonus and finally formed a frozen shoulder with elbow flexion contracture. Two factors contributed to this serious complication: first, autonomic dysreflexia triggered by minor malfunction and/or irritation from the cystostomy catheter; and second, the medical staff lacked sufficient experience in and knowledge about the management of autonomic dysreflexia.It is of the utmost importance for medical staff engaging in rehabilitation of spinal patients to share information regarding triggers of autonomic dysreflexia and to be thorough in ensuring proper medical management.

View full abstract

Oxytocin, a neurohypophyseal hormone, is synthesized in the magnocellular neurosecretory cells located in the paraventricular and supraoptic nuclei of the hypothalamus, and is secreted into the systemic blood flow from the axon terminals. It is well known that plasma oxytocin is involved in contraction of the uterus during parturition and milk ejection reflex during lactation. It has recently come to the attention of researchers that oxytocin receptors are abundant in the brain and oxytocin is involved in higher brain functions such as bonding between parent and child and trust. Since it was difficult to identify neurohypophyseal hormones, oxytocin- and vasopressin-producing neurons in a living cell, we tried to generate transgenic animals that express fluorescent proteins as a tag protein to visualize neurohypophyseal hormones. In this paper we review the use of genetic modification techniques in the fluorescent visualization of oxytocin neurons and its application.

View full abstract

The purpose of this study was to analyze the effects of using audiovisual materials in gerontological nursing exercises. Sixty-five second year nursing students watched audiovisual materials of scenes of communication between simulated patients (SP) with functional difficulties and other nursing students, and then presented reports on this exercise. We analyzed the reports of the nursing students, and we could determine several categories of description in their reports, which suggest that they could perceive indescribable facial expressions of the SP and mutual communication by unspoken messages between the SP and students, and that they could understand the patientsʼ nonverbal messages through the patientʼs expressions and reactions. These results suggest that using audiovisual materials in gerontological nursing exercises is effective in helping nursing students to develop a better understanding of the psychology of the elderly with functional difficulties.

View full abstract