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Biomedical subjects

K Baba

Publications and source records attributed to K Baba.

At least 163 records · Page 9Linked to original sources
PubMed1997

The validity and utility of disease detection methods and of occlusal therapy for temporomandibular disorders.

Our evaluation of the clinical usefulness or devices for the diagnosis or treatment of temporomandibular disorders (TMD) led to the conclusion that the only current gold standard for TMD is a global clinical examination, because none of the instruments can be said to provide more than ancillary documentation and none have proven diagnostic validity or utility. Regarding the therapeutic efficacy of occlusal adjustment, we could find no comparative studies that test the efficacy of occlusal adjustment in preventing TMD. The studies we reviewed on the relationship of occlusion to TMD are not convincing, powerful, or practical enough to make any recommendations about a causal association.

Centric Relation↗
PubMed1997

Characterization of dynamics of the psbD light-induced transcription in mature wheat chloroplasts.

Dynamical aspects of three chloroplast promoters responding to change in light condition were examined in mature chloroplasts of wheat (Triticum aestivum) by in vitro transcription. The wheat psbD/C operon has four distinct promoters, two of which named as D/C-3 and D/C-4 promoters dominantly function in mature chloroplasts to produce the mRNAs encoding D2/CP43 and CP43 alone, respectively. Activity of the D/C-3 promoter in mature chloroplasts was reduced to less than 30% by 24 h dark adaptation and recovered by re-illumination to the original level within 30 to 60 min. The activation of the D/C-3 promoter which requires de novo cytoplasmic protein synthesis was induced by low fluence of light (e.g. 16 microE m(-2) s(-1)), but the extent of activation increased with increasing light fluence. The accumulation of mRNAs from the D/C-3 promoter saturated at 2- to 3-fold higher level within 2 h when the dark-adapted seedlings were transferred to the light at 72 microE m(-2) s(-1), concomitant with the increase in rate of D2 synthesis, suggesting that synthesis of D2 in mature chloroplasts is controlled via the D/C-3 promoter activity in a light-dependent way. Activity of the D/C-4 promoter slightly increased in the dark and decreased in the light. Effect of light on the psbA promoter activity was not observed at all in mature chloroplasts. In vitro transcriptional analysis of the D/C-3 promoter with 5' deletion mutations revealed that at least two cis elements which are located within the sequences of -78 to -47 and -46 to -29 of the transcription initiation site, respectively, act as enhancing elements in the D/C-3 promoter. The light-switching element of the transcription, however, was suggested to be located in the core promoter sequence downstream of the -35 element.

Chloroplasts↗
PubMed1997

Clinical significance of tissue inhibitor of metalloproteinase expression in gastric carcinoma.

Tissue inhibitor of metalloproteinase (TIMP) has been reported to inhibit tumour invasion through an inactivation of matrix metalloproteinase (MMP) both in vitro and in vivo. Among the TIMP family, TIMP-1 possesses not only proteinase inhibitory activity but also a growth-promoting function. However, the significance of the expression of TIMP-1 in human gastric carcinoma tissue has yet to be clarified. In 50 examined cases of gastric carcinoma, 44 (88%) cases showed a higher expression of TIMP-1 mRNA in the biopsy samples from the tumour tissue (T) than in the biopsy samples from the corresponding normal tissue (N), as determined by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR). In a multivariate analysis, the T/N ratio of TIMP-1 mRNA was found to be an independent factor influencing the depth of tumour invasion and was the second most important factor in determining the prognosis of patients. As RT-PCR assay can be performed on biopsy specimens obtained before surgery, an evaluation of the TIMP-1 expression in biopsy specimens by RT-PCR may thus provide useful preoperative information on tumour aggressiveness.

Adult↗
PubMed1997

Structural alterations in the tunica albuginea of the penis: impact of Peyronie's disease, ageing and impotence.

OBJECTIVE: To investigate whether changes in the structure of the tunica albuginea influence the development of erectile dysfunction. PATIENTS AND METHODS: Biopsy specimens taken from the tunica of 64 patients (both potent and impotent) with and without Peyronie's disease were evaluated. Tissue samples were stained and examined under light and electron microscopy, and the concentration of elastic fibres present in each was measured using computerized image analysis. RESULTS: The concentration of elastic fibres was lower in impotent than in potent patients (P = 0.0365) and was also significantly less in patients with Peyronie's disease. Furthermore, the concentration of elastic fibres decreased with age. Electron and light microscopy revealed the presence of distinct alterations in the tunica albuginea in impotent patients and patients with Peyronie's disease that might interfere with function. CONCLUSION: The decrease in elastic fibre concentration and changes in microscopic features may contribute to erectile dysfunction by impairing the veno-occlusive function of the tunica albuginea.

Adolescent↗
PubMed1997

Pneumomediastinum in newborns induced by the Elder CPR/demand valve during resuscitation.

Two term and one post-term newborn infants with pneumomediastinum associated with the use of an Elder CPR (cardiopulmonary resuscitation)/demand valve during resuscitation are described. Because of apnea or irregular gasping respiration after vaginal delivery, they received repetitive positive-pressure ventilation with this resuscitator, which is designed to provide 100% oxygen with a limited pressure of up to 40 cmH2O. Following resuscitation, the infants had tachypnea and diminished breath sounds. Roentgenograms and computed tomography of the chest revealed pneumomediastinum in all three and cervical subcutaneous emphysema in one. They required 25-30% oxygen for 3-14 days until they recovered spontaneously. Thus, pressures as low as 40 cmH2O can cause barotrauma, and the Elder resuscitator, even when functioning properly, may injure the lungs of newborn infants.

Asphyxia Neonatorum↗
PubMed1997

Interstitial pneumonitis probably induced by cyclophosphamide in nephrosis.

A case of interstitial shadows associated with oral cyclophosphamide therapy in a 32-month-old girl with steroid-resistant nephrotic syndrome, who was admitted to the Nishi-Kobe Medical Center with systemic edema, is reported. Due to the lack of response to prednisolone, cyclophosphamide was also administered orally at a dose of 3 mg/kg per day, 4 weeks after the start of steroid therapy. Approximately 3 weeks after the combination treatment she developed a fever, dry cough and cyanosis. Radiographic examination showed diffuse ground-glass shadow in both lungs, presumably indicating that she had interstitial pneumonitis. Her pulmonary signs and symptoms deteriorated despite various antimicrobial treatments. A discontinuation of cyclophosphamide and the administration of high-dose methylprednisolone yielded a dramatic improvement. These findings suggest that the diffuse pulmonary disease in this case was induced by cyclophosphamide. Since interstitial pneumonitis may be fatal and irreversible, attention should be paid to this rare complication even in patients undergoing low-dose oral cyclophosphamide treatment.

Alkylating Agents↗
PubMed1997

An evaluation of the system to control blood flow in maintaining goat fetuses on arterio-venous extracorporeal membrane oxygenation: a novel approach to the development of an artificial placenta.

We compared various methods to control blood flow for extrauterine incubation of goat fetuses without lung respiration using arterio-venous extracorporeal membrane oxygenation via umbilical vessels to develop a suitable system for a long-term life support system for premature neonates. In twenty-seven consecutive preparations of goat fetuses, 4 designs (System 1, manual flow control without a reservoir; System 2, manual flow control with an arterial open-top reservoir; System 3, semiautomatic flow control with an arterial open top reservoir; and System 4, semiautomatic flow control with a tube occluder and an arterial open top reservoir) were tested in terms of the duration of incubation periods during which fetuses were kept under stable conditions. The incubation periods became prolonged with the advancement of the system (System 1, 5.4 h; System 2, 11.6 h; System 3, 64.8 h; and System 4, 159.8 h medians of the incubation periods). The incubation periods with System 4 were significantly longer compared to those with System 1 and System 2. These results suggest that, for extrauterine incubation of goat fetuses using arterio-venous extracorporeal membrane oxygenation via umbilical vessels, the method to control blood flow is of utmost importance for long-term maintenance, and thus a control system with the fixed vascular resistance of the extracorporeal circuit is applicable to long-term maintenance of premature goat fetuses.

Animals↗
PubMed1997

Development of the undulation pump total artificial heart.

The undulation pump is a small size continuous flow displacement type blood pump that has been developed for an artificial heart. Using undulation pumps, 2 types of implantable total artificial hearts (TAHs), the undulation pump TAH (UPTAH) type 1 (UPTAH 1) and UPTAH type 2 (UPTAH 2) were developed. Both UPTAHs were designed to be small enough to implant into the chest of a goat, the experimental animal. UPTAH 1 could be reduced in size to 75 mm in diameter and 78 mm in length. The weight was 520 g. UPTAH 2 could be reduced in size to 75 mm in diameter and 80 mm in length. The weight was 650 g. UPTAH 2 could be tested in an animal experiment using an adult female goat weighing 52.3 kg. The UPTAH 2 could be implanted successfully into the goat's chest with a good fit. The goat stood after the surgery and extubation and survived for 3 h and 40 min; thus, the potential of the UPTAH for a practical implantable TAH was demonstrated.

Animals↗
PubMed1997

A case of Kawasaki disease with coronary artery aneurysms documenting Yersinia pseudotuberculosis infection.

A case of a 5-year-old boy who fulfilled all the criteria for Kawasaki disease (KD) was described. He had associated bilateral coronary artery aneurysms. Our study revealed the isolation of Yersinia pseudotuberculosis in stool cultures, and the elevation and seroconversion of the agglutination antibody titres, and hence he was diagnosed as Y. pseudotuberculosis infection-positive. We also demonstrated the positive mitogenic activity of the culture supernatant of the isolated bacterium from the patient and detected Y. pseudotuberculosis-derived mitogen by PCR. This case therefore suggests that Y. pseudotuberculosis might be closely related to the cause of KD.

Angiography↗
PubMed1997

Real-time processable three-dimensional US in obstetrics.

Results with real-time processable three-dimensional ultrasound (US) were assessed in 57 normal fetuses and two fetuses with hydramnios. Volume scanning time was 4 seconds, and a complete three-dimensional fetal image was displayed at the end of scanning. Although this method was limited in some respects, such as viewing direction, it was very useful when performed in conjunction with conventional tomographic US because of its speed and because some components were depicted more clearly.

Female↗
PubMed1997

Age decreases nitric oxide synthase-containing nerve fibers in the rat penis.

PURPOSE: To study the effect of aging on erectile function in a rat model. MATERIALS AND METHODS: We investigated: 1) the number and distribution of nerve fibers within the corpus cavernosum and dorsal nerve containing vasoactive intestinal polypeptide (VIP) and nitric oxide synthase (NOS); and 2) the erectile response to apomorphine (a central dopamine receptor agonist), electrostimulation of the cavernous nerve, and intracorporeal papaverine injection. RESULTS: The number of NOS-containing nerve fibers was significantly less in the old rats (24 months) than in the young (2.5 months) and intermediate (8.5 months)-aged (63.3 +/- 3.35 vs. 135.1 +/- 10.88 [p < or = 0.0002] and 127.8 +/- 11.65 [p < or = 0.0002]). The number of erections induced by apomorphine was significantly less in the old rats than in the young (1.0 +/- 3.1 vs. 3.6 +/- 0.26; p < 0.002). With electrostimulation, the latency period before the onset of the intracavernous pressure rise was noted to increase with age (2.3 +/- 0.24 sec. for the young vs. 6.77 +/- 0.98 sec. for the old, p < or = 0.0001). The maximal intracavernous pressure after intracavernous papaverine injection decreased with age. CONCLUSION: The erectile mechanism appears to remain intact as rats age, but the response to central and peripheral stimulation decreases. The reduction in NOS-containing nerve fibers might account for these observations.

Aging↗
PubMed1997

Chromosome abnormality in solid and cystic tumor of the pancreas.

We report a case of a solid and cystic tumor of the pancreas with chromosomal abnormalities. The patient, a 13-yr-old girl, successfully underwent surgical excision and has been asymptomatic for more than 10 months. The tumor had two parameters suggesting malignant potential; a local invasion into a bile duct, and high mitotic activity. Chromosomal analysis showed two complex abnormalities, of which double loss of X chromosomes and trisomy for chromosome 3 were common. The complexity and polyclonality may stem from a clonal evolution. The observed abnormalities may provide a crucial clue to the understanding of the developmental process of this neoplasm.

Adolescent↗
PubMed1997

[A case of 47XYY syndrome presenting with male infertility].

A 32-year-old man was referred to our hospital for primary infertility of a 4.5-year duration. Neither character nor intelligence disorders were observed. Bilateral testes measured 16 ml each. Sperm density was 0-0.1 x 10(6)/ml on 3 separate occasions. Endocrine examinations were all within normal limits. Maturation arrest was found on testicular biopsy. Karyotyping showed 47, XYY inversion. Polymerase chain reaction revealed no deletion of the azoospermic factor (AZF) gene on the Y chromosome. This is the 6th case reported in the Japanese literature of the 47XYY syndrome presenting with male infertility.

Adult↗
PubMed1996

Expression of ornithine decarboxylase mRNA in gastric carcinoma.

BACKGROUND: Ornithine decarboxylase (ODC) is a key rate-limiting enzyme in polyamine biosynthesis. Several studies using an enzyme assay revealed that the ODC activity was higher in tumor tissue than in normal tissue. However, there is little information on the mRNA status of ODC in surgical specimens. ODC is a transcriptional target gene of c-myc. METHODS: cDNA was obtained by reverse transcription (RT) from fresh specimens of 56 surgical pairs of primary gastric carcinomas and corresponding normal tissue specimens. The ODC and c-myc mRNAs were subsequently detected by means of the polymerase chain reaction. The tumor/normal (T/N) ratio of ODC expression was calculated after correcting for glyceraldehyde-3-phosphate dehydrogenase as an internal control. The T/N ratio of ODC was plotted against that of c-myc. RESULTS: The corrected expression levels of ODC mRNA in the tumor were greater than those of the normal mucosa in 36 of 56 cases (64%). The cases of tumor with vascular vessel invasion showed a higher T/N ratio than those without vascular invasion (P < 0.01). Similarly, female patients showed a higher T/N ratio than male patients (P < 0.01). There was a significant correlation between the expressions of both ODC and c-myc genes (P < 0.05). CONCLUSIONS: The findings imply that (1) overexpression of ODC mRNA in tumor tissue may correlate with aggressive biologic behavior, such as vascular vessel invasion, and (2) there is an intimate correlation between ODC and c-myc genes.

Base Sequence↗
PubMed1996

In situ hybridization analysis of substance P receptor in the rat retina.

Substance P receptor is known to provide a principal interface between tachykinin peptides and tachykinin-sensitive cells in retinal circuitry and to produce several physiological functions such as excitation of ganglion cells. We reported results of in situ hybridization analysis of substance P receptor in rat retina using digoxigenin-labeled RNA probes to yield discrete cell labeling. Distinct hybridization signal was present in a great majority of ganglion cells that provide retinal fibers to a central target. It was also present in a subpopulation of amacrine cells. Following optic nerve crush, ganglion cells lost their hybridization signal in a time-dependent manner, while hybridization-positive amacrine cells were persistently seen. From the results, we identified the hybridization message as distinctly localized to two systems, output cells and intrinsic cells in retinal circuitry.

Animals↗
PubMed1996

Apoptosis in antibody-dependent monocyte-mediated cytotoxicity with monoclonal antibody 17-1A against human colorectal carcinoma cells: enhancement with interferon gamma.

Antibody-dependent cell-mediated cytotoxicity (ADCC) has been considered to be one of the main effector mechanisms by which unconjugated monoclonal antibody (mAb) 17-1A can exert an antitumor effect in vivo. Since the apoptotic pathway as well as the necrotic pathway have been shown to be utilized in various cytotoxic effector mechanism, we investigated the role of apoptosis in ADCC mediated by monocytes (ADMC) using mAb 17-1A as an antibody and the human colorectal carcinoma cell line, COLO205, as target cells in vitro. The implications of the apoptosis during ADMC was demonstrated by means of both a DNA fragmentation assay and a TdT-mediated dUTP-biotin nick end labeling (TUNEL) assay. Furthermore, interferon gamma (IFN gamma) was also found to enhance the induction of apoptosis significantly. The addition of superoxide dismutase did not reduce the level of the apoptosis, although superoxide anion (O2-) was observed to be produced. However, the release of tumor necrosis factor alpha (TNF alpha) was significantly enhanced during ADMC, while, in addition, apoptosis was significantly inhibited by the addition of anti-TNF alpha antibody. These findings indicated that apoptosis might be implicated in ADMC with mAb 17-1A, which was augmented by IFN gamma, while, in addition, TNF alpha may also be one of the major mediators of apoptosis.

Antibodies, Monoclonal↗