Search PubMed⌕ Search

Biomedical subjects

N Mukai

Publications and source records attributed to N Mukai.

At least 19 recordsLinked to original sources
PubMed2003

The effects of various therapeutic measures on shoulder strength and muscle soreness after baseball pitching.

AIM: This study was intended as an investigation of the effects of various therapeutic measures on the shoulder strength and muscle soreness after baseball pitching. METHODS EXPERIMENTAL DESIGN: participants threw 98 pitches in a simulated single game. The mode of the therapeutic measures after pitching were classified into 4 groups; the control group (CON), the ice treatment group (IT), the light shoulder exercise group (LSE) and the ice treatment with LSE group (ILSE). Each therapeutic measure was applied to the dominant shoulder immediately after pitching. PARTICIPANTS: 7 healthy, skilled baseball pitchers. MEASURES: both shoulder strength and muscle soreness were measured before pitching, immediately after pitching (Post-P), at the time of the therapeutic measure (Post-TM), and 24 hours after pitching (Post-24 h). RESULTS: All 4 groups showed shoulder strength losses in shoulder abduction, internal/external rotation with no shoulder abduction or with the shoulder abducted to 90 degrees immediately after pitching. ILSE had greater recovery from Post-P values at Post-TM or Post-24 h than the other methods in all 5 shoulder strengths. On the other hand, the soreness in shoulder internal rotation was increased significantly from Post-P and continued by Post-24 h. Both IT and ILSE had beneficial effects on reducing the shoulder muscle soreness at Post-TM or Post-24 h. CONCLUSION: The findings of this study suggested that ILSE was the optimal therapeutic measure against decreased shoulder strength or increased shoulder muscle soreness resulting from the repetitive baseball pitching.

Adult↗
PubMed2003

The effects of various therapeutic measures on shoulder range of motion and cross-sectional areas of rotator cuff muscles after baseball pitching.

AIM: The purpose of this study was to investigate the effects of various therapeutic measures on the shoulder range of motion (ROM) and muscle cross-sectional area (mCSA) of rotator cuff muscles after baseball pitching. METHODS EXPERIMENTAL DESIGN: a mode of therapeutic measures was classified in 4 groups; the control (CON), ice treatment (IT), light shoulder exercise (LSE) and ice treatment with LSE (ILSE) groups. Each therapeutic measure was performed after pitching. PARTICIPANTS: 7 healthy, skilled baseball pitchers. MEASURES: ROM and mCSA were measured before pitching, immediately after pitching, at the time of the therapeutic measure, and 24 hours after pitching. Shoulder ROM at 90 inverted exclamation mark of abduction included internal rotation (IROM), maximum internal rotation (IMROM), external rotation (EROM) and maximum external rotation (EMROM). RESULTS: In all groups, both IROM and IMROM were significantly decreased after pitching compared with the pre-exercise values and conversely both EROM and EMROM were significantly increased. The mCSA of all rotator cuff muscles were increased significantly after pitching. For IMROM, ILSE showed a significant recovery at the post-therapeutic measure compared with the others and at 24 hours after pitching compared with IT, respectively. For IROM, both LSE and ILSE showed significant recovery compared with CON at the post-therapeutic measure. For the mCSA of external muscles, ILSE showed a greater decrease at the post-therapeutic measure than the others, and at 24 hours after pitching than CON. CONCLUSION: This study suggested the possibility that ILSE was more effective to recover ROM and decrease mCSA than the other methods.

Adult↗
PubMed2001

Beer brewing using a fusant between a sake yeast and a brewer's yeast.

Beer brewing using a fusant between a sake yeast (a lysine auxotrophic mutant of sake yeast K-14) and a brewer's yeast (a respiratory-deficient mutant of the top fermentation yeast NCYC1333) was performed to take advantage of the beneficial characteristics of sake yeasts, i.e., the high productivity of esters, high tolerance to ethanol, and high osmotolerance. The fusant (F-32) obtained was different from the parental yeasts regarding, for example, the assimilation of carbon sources and tolerance to ethanol. A brewing trial with the fusant was carried out using a 100-l pilot-scale plant. The fusant fermented wort more rapidly than the parental brewer's yeast. However, the sedimentation capacity of the fusant was relatively low. The beer brewed using the fusant contained more ethanol and esters compared to that brewed using the parental brewer's yeast. The fusant also obtained osmotolerance in the fermentation of maltose and fermented high-gravity wort well.

Journal Article↗
PubMed2001

New graphics models for PC based ocular surgery simulator.

High-end graphics workstations (GWS) have been used for surgical simulators utilizing Computer Graphics (CG) and Virtual Reality (VR) technologies. This is because the simulators need lots of computing power, mainly for collision detection among objects modeled as a set of polygons. In this paper, we propose to use mathematical functions to model objects for collision detection. However, for graphic display we continue to use polygonal representation. Using the new model, we have developed a PC based ocular surgery simulator, which creates realistic surgery image in real-time. The computation time was found to be much lower than that in the conventional method.

Computer Graphics↗
PubMed2000

Reversible phase transitions in polymer gels induced by radiation forces.

Many polymer gels undergo reversible, discontinuous volume changes in response to changes in the balance between repulsive intermolecular forces that act to expand the polymer network and attractive forces that act to shrink it. Repulsive forces are usually electrostatic or hydrophobic in nature, whereas attraction is mediated by hydrogen bonding or van der Waals interactions. The competition between these counteracting forces, and hence the gel volume, can thus be controlled by subtle changes in parameters such as pH (ref. 4), temperature, solvent composition or gel composition. Here we describe a more direct influence on this balance of forces, by showing that the radiation force generated by a focused laser beam induces reversible shrinkage in polymer gels. Control experiments confirm that the laser-induced volume phase transitions are due to radiation forces, rather than local heating, modifying the weak interactions in the gels, in agreement with previous observations of light-induced chain association in polymer solutions. We find that, owing to shear-relaxation processes, gel shrinkage occurs up to several tens of micrometres away from the irradiation spot, raising the prospect that the combination of stimuli-responsive polymer gels and laser light might lead to new gel-based systems for applications such as actuating or sensing.

Journal Article↗
PubMed2000

Vitreous surgery simulator.

OBJECTIVE: To reduce the surgical risks to patients and expose surgeons to surgical experience and complications, we have developed a practical system of vitreous surgery using virtual-reality technology. METHODS: The system is composed of high-resolution color stereo binoculars, haptic devices, foot switches, and a high-speed graphics computer. To simulate vitreous surgery, we created several virtual patient eyes with retinal diseases such as preretinal membranes and subretinal neovascular tissue at the fovea. RESULTS: The simulator provided the trainees with an operating environment similar to an actual one, and allowed them to learn to maneuver surgical instruments and remove proliferative tissue on the retina, under the retina, or both. This system allowed surgeons to avoid iatrogenic complications through visual signs such as retinal hemorrhage when the instrument contacted the retinal surface. CONCLUSIONS: This simulator may not only be suitable for residents to learn ocular surgical techniques but may also allow veteran surgeons to develop new surgical methods and skills.

Computer Simulation↗
PubMed2000

Pulmonary sequestration associated with aspergillosis.

Pulmonary sequestration involves an abnormal pulmonary tissue separated from the normal pulmonary parenchyma, not connected to the tracheobronchial tree and supplied by a systemic artery. A case of intralobar pulmonary sequestration is presented. Case; a 49-year-old male was admitted to our hospital complaining of fever, cough and sputum production. Sputum culture resulted in a large growth of Aspergillus niger. Angiography showed an abnormal blood supply from the abdominal aorta to the right lower lobe. Right lower lobectomy was performed. The postoperative courses are uneventful.

Aspergillosis↗
PubMed2000

[Two cases of primary carcinoma developed in a vesical diverticulum treated with ileal neobladder for total bladder replacement].

Two cases of carcinoma developed in vesical diverticulum were encountered. Both these males, the first, 66-year-old and the second case, 68-year-old gentleman, visited our clinic with a complaint of asymptomatic gross hematuria. Total cystectomy was performed, and an ileal neobladder was constructed for total bladder replacement in both two cases. Pathological examination of the first case revealed transitional cell carcinoma, and the second case showed adenocarcinoma mixed with transitional cell carcinoma. Although primary carcinoma developed in vesical diverticulum was initially reported by Williams in 1883, adenocarcinoma is very rare. The diagnosis is often challenging and the prognosis is dire. Both our cases were successfully treated with total cystectomy and an ileal neobladder was constructed for total bladder replacement. Careful management and aggressive therapy for such patients may make even cure possible.

Adenocarcinoma↗
PubMed1999

Physiologic and morphologic properties of motoneurons and spindle afferents innervating the temporal muscle in the cat.

Little is known about physiology and morphology of motoneurons and spindle afferents innervating the temporalis and on synaptic connections made between the two. The present study was aimed at investigating the above issues at the light microscopic level by using the intracellular recording and horseradish peroxidase or biotinamide labeling techniques and by the use of succinylcholine (SCh) for the classification of spindle afferents in the cat. Temporalis motoneurons had dendritic trees that ranged from a spherical form to an egg-shaped form. The shape deformation was more prominent for the dendritic trees made by motoneurons located closer to the nuclear border. No axon collaterals of the motoneurons were detected. On the basis of the values for the dynamic index after SCh infusion, temporalis spindle afferents were classified into two populations: presumptive groups Ia and II. The spindle afferents terminated mainly in the supratrigeminal nucleus (Vsup), region h, and the dorsolateral subdivision (Vmo.dl) of the trigeminal motor nucleus (Vmo). The proportion of group Ia afferent terminals was lower in the Vsup than that of group II afferents. In the Vmo.dl, the proportion of group Ia afferent terminals was nearly even throughout the nucleus, but that of group II afferent terminals increased in the more outlying regions. The proportion of terminal distribution in the central region of Vmo.dl was higher for group Ia than group II. The frequency of contacts (presumptive synapses) made by a single spindle afferent on a motoneuron was higher for group Ia than group II. The present study provided evidence that the central organization of spindle afferent neurons is different between groups Ia and II.

Animals↗
PubMed1999

Malignant mesothelioma of the tunica vaginalis testis: report of a case.

We describe herein the case of a 68-year-old man with malignant mesothelioma of the tunica vaginalis testis. The pathological diagnosis was based upon the clinical findings, gross and microscopic morphology, and special stains. Malignant mesothelioma is a rare tumor associated with asbestos exposure that can be effectively treated with orchidectomy via an inguinal approach.

Aged↗
PubMed1998

Serum insulin-like growth factor-I, insulin-like growth factor binding protein-3, sex steroids, osteocalcin and bone mineral density in male and female rats.

Although it has been reported that the rate of weight gain and linear growth increases markedly during puberty in rats, little is known about the relationship between endocrine changes and bone mineral density (BMD) changes upon sexual maturation in these animals. The aim of this study was to examine the levels of serum insulin-like growth factor-I (IGF-I), IGF binding protein (IGFBP)-3, sex steroids and osteocalcin, and the changes in BMD in normal aging male and female rats. Male rats exhibited increases in serum IGF-I and IGFBP-3 concentrations before increases in serum testosterone levels. IGF-I and testosterone peaked at 9 weeks of age, and thereafter remained in a steady state, whereas IGFBP-3 reached a peak at 7 weeks of age, and then gradually declined. A strong correlation between serum IGF-I and IGFBP-3 levels was found in subjects 3-9 weeks old. A highly significant correlation between serum IGF-I and testosterone levels was also found. In females, serum 17 beta-estradiol, IGF-I and IGFBP-3 levels increased gradually from 3 to 5 weeks old, peaked at 9 weeks, and then decreased slowly thereafter. The correlation coefficient between serum IGF-I and IGFBP-3 was highly significant. The correlation coefficient between serum IGF-I and 17 beta-estradiol levels was weak, although it was strongest when the subjects were 3-9 weeks old. Serum osteocalcin is a marker of bone formation; its level remained relatively high from 3 to 9 and from 3 to 7 weeks of age in males and females, respectively, although osteocalcin in both sexes declined gradually with age. As for bone mass, sharp increases in BMD in the tibia, femur and lumbar vertebrae appeared earlier in female than in male rats, and the BMD in females tended to be higher than in males between 5 and 9 weeks old. After 9 weeks of age, BMD in males was higher than that in females, as BMD in males continued to increase whereas females tended to remain in a steady state after this stage. The correlation coefficients between tibial BMD and serum IGF-I or IGFBP-3 levels were highly significant when the subjects were from 3 to 9 weeks old. Taken together, these results suggest that BMD development occurs earlier in female than in male rats. This sex-related difference in changes in the BMD pattern may result from the earlier onset of puberty in females, and from sex-specific differences in concentrations of IGF-I, IGFBP-3 and sex steroids during maturation.

Age Factors↗
PubMed1997

Effect of resistance exercise training on bone formation and resorption in young male subjects assessed by biomarkers of bone metabolism.

We studied the effects of high intensity resistance exercise training on bone metabolism in 17 young adult Oriental males (23-31 years) by measuring sensitive biomarkers of bone formation and resorption. The subjects were assigned to a training group and a sedentary group. The training group followed a weight training program three times per week for 4 months. In the training group, serum osteocalcin concentration and serum bone-specific alkaline phosphatase activity were significantly increased within the first month after the beginning of resistance exercise training, and the elevated levels remained throughout the training period, while there was no significant change in plasma procollagen type-I C-terminal concentration. Urinary deoxypyridinoline excretion was transiently suppressed and returned to the initial value but was never stimulated during the 4 months. These results suggest that the resistance exercise training enhanced bone formation without prior bone resorption. In the sedentary group, there was no significant difference in bone metabolic markers except plasma procollagen type-I C-terminal, which continuously decreased during the experimental period. There were no significant changes in total and regional bone mineral density in either group. In conclusion, (1) resistance exercise training increased markers of bone formation, while it transiently suppressed a marker of bone resorption, and (2) such adaptive changes of bone metabolism to resistance exercise training occurred during the early period of the training, before changes in bone density were observable through densitometry.

Adult↗
PubMed1994

[Clinical feature and quality of life of urinary diversion patients with bladder cancer].

A clinical survey was performed on 95 cases who were treated by total cystectomy with urinary diversion at our hospital between August 1971 and March 1992. Urinary diversions were classified by ureterocutaneostomy (Group I) in 27 patients, ileal or colon conduit (Group II) in 45 and continent urinary reservoir (Group III) in 23. The patients ranged in age from 29 to 76 with an average age of 60.6 year and the male to female ratio was 68 to 27. Histopathological typing of bladder cancers showed 82 cases of transitional cell carcinoma, 8 cases of squamous cell carcinoma, 4 cases of adenocarcinoma, and 1 mixed carcinoma with transitional cell carcinoma, squamous cell carcinoma and adenocarcinoma. At present, patients alive of Group I, II and III were 14, 27 and 16, respectively, totally 57 (60.0%) patients were alive. Five-year actuarial survival rates of Group I, II and III were 45.2%, 54.1%, and 56.8%, respectively. A questionnaire survey was carried out to assess the quality of life (QOL) of 57 alive patients. The analysis of replied questionnaire showed that even all patients of each groups adapted to the basic life activities after urinary diversion, though a step forward quality of life with hobby, travel and job were decreased postoperatively in 3 groups. We obtained results that the patients of Group III were more satisfactory with daily (bath) and social life (job) than the patients of Group I, II and preoperatively. We have a new comprehension of importance of enough informed consent and mental support to the urinary diversion patients preoperatively, and of a new operative procedure not to impair the QOL.

Adenocarcinoma↗
PubMed1994

[Leiomyosarcoma of the prostate: response to treatment with cisplatin, etoposide and methotrexate chemotherapy: a case report].

Leiomyosarcoma of the prostate gland is rare, and only 44 of these neoplasms have been reported in Japan. We experienced a case in a 17-year-man suffering from leiomyosarcoma and lung metastasis. The patient was treated with chemotherapy consisting of cis-platin, etoposide and methotrexate. He improved considerably and was discharged after five months. However the disease recurred in the pelvis and the lungs. The patient was unresponsive to further chemotherapy and died six months later.

Adolescent↗
PubMed1993

[An experience with a continent appendix stoma].

The submucosally embedded in situ appendix guarantees an ideal continence mechanism in patients with ileocecal urinary reservoirs. To date this modification of the Mainz pouch technique was performed successfully in 10 patients between September 1990 and October 1992. Pouch capacity ranged from 350 ml to 900 ml (mean: 565 ml), frequency of intermittent self-catheterization ranged from 3 to 7 times per day (mean: 4.4-5.4 times) and complete urinary continence without difficulty of self-catheterization was obtained in eight patients. Two patients with stomal stenosis needed to indwell a catheter. The follow up periods ranged from 3 to 24 months (mean: 14.7 months). The main advantages of appendix stoma technique are shorter operation time, a short ileal segment, no risk of nipple gliding or prolapse, no need for staples, thereby decreasing significantly the risk of stone formation, and facilitating easy catheterization. This method seemed to be valuable for continent urinary reservoir assuring patients of high quality of life.

Adenocarcinoma↗
PubMed1993

[Two cases of bladder cancer in patients with chronic renal failure].

We report here two cases of bladder cancer in patients with chronic renal failure who had been treated with hemodialysis. Case 1: A 58-year-old male on hemodialysis for 3 years visited with a complaint of gross hematuria. Transurethral resection of the bladder tumor (TUR-Bt) was performed and histopathological examination showed grade 1, stage pTa transitional cell carcinoma (TCC). The patient was followed for 4 years postoperatively without recurrence. Case 2: A 64-year-old male with hemodialysis for 1 week was referred to our department with a gross hematuria. TUR-Bt was conducted and histopathological findings showed grade 2, stage pT1b TCC. In April, 1992, he revisited our hospital with bladder tamponade due to massive hematuria, and TUR-Bt was performed. Histopathologically, the tumors were grade 2, stage pT2 TCC. He was followed for 1 year without recurrence.

Carcinoma, Transitional Cell↗