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H Minakuchi

Publications and source records attributed to H Minakuchi.

12 recordsLinked to original sources

Monolithic LC columns.

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Chromatography, High Pressure Liquid↗

Randomized controlled evaluation of non-surgical treatments for temporomandibular joint anterior disk displacement without reduction.

The common methods for treating anterior disk displacement without reduction (ADDwor) are not based on randomized controlled clinical trials. Our study evaluated non-surgical treatments in 69 MRI-confirmed ADDwor subjects (m/f = 6/63). Subjects were randomly assigned to a control group and one of two treatment groups. Outcomes included maximum mouth opening, visual analogue scale of pain, and daily activity limitation. Calibrated examiners collected data at the initial interview and at 0, 2, 4, and 8 weeks of treatment. At the eight-week point, within-group improvements were present for all variables, for all groups. Between-group differences were not highly evident, with only mean daily activity limitation for the self-care/NSAID group being significantly lower than that of the occlusal appliance/jaw mobilization + self-care/NSAID group at the two- and four-week time-points. These results suggest that ADDwor subjects will improve with only minimal treatment intervention, and no significant difference was evident for the treatments tested and the control condition.

Activities of Daily Living↗

Performance of a monolithic silica column in a capillary under pressure-driven and electrodriven conditions

A continuous macroporous silica gel network was prepared in a fused-silica capillary and evaluated in reversed-phase liquid chromatography. Under pressure-driven conditions, the monolithic silica column derivatized to C18 phase (100 microns in diameter, 25 cm in length, silica skeleton size of approximately 2.2 microns) produced plate heights of about 23 and 81 microns at 0.5 mm/s with a pressure drop of 0.4 kg/cm2, and at 4.0 mm/s with 3.6 kg/cm2, respectively, in 90% acetonitrile for hexylbenzene with a k value of 0.7. The separation impedance, E, calculated for the present monolithic silica column was much smaller at a low flow rate than those for particle-packed columns, although higher E values were obtained at a higher flow rate. Considerable dependence of column efficiency on the linear velocity of the mobile phase was observed despite the small size of the silica skeletons. A major source of band broadening in the HPLC mode was found in the A term of the van Deemter equation. The performance of the continuous silica capillary column in the electrodriven mode was much better than that in the pressure-driven mode. Plate heights of 7-8 microns were obtained for alkylbenzenes at 0.7-1.3 mm/s, although the electroosmotic flow was slow. In HPLC and CEC mode, the dependency of plate height on k values of the solutes was observed as seen in open tube chromatography presumably due to the contribution of the large through-pores. Since monolithic silica capillary columns can provide high permeability, the pressure-driven operation at a very low pressure can afford a separation speed similar to CEC at a high electric field.

Journal Article↗

Four-year longitudinal course of TMD symptoms in an adult population and the estimation of risk factors in relation to symptoms.

AIMS: To investigate the natural course of symptoms of temporomandibular disorders (TMD) in a non-patient population and to estimate the strength of the relationship between several hypothesized risk factors and precipitation and perpetuation of the symptoms. METHODS: A total of 672 randomly selected citizens of Okayama City was requested to answer the same self-administered questionnaire that they had answered 4 years earlier. The mailed questionnaire failed to reach 58 subjects at the second survey, and 367 of the remaining subjects (59.8%) responded. The fluctuation of TMD symptoms was assessed by comparison of 6 pairs of answers for questions regarding temporomandibular joint (TMJ) pain, limitation of mouth opening, TMJ noise, headache, neck pain, and shoulder stiffness. Six factors (age under 40, female, clenching habit, history of extrinsic trauma, sleep disturbance, and family history of TMD) were tested for their relative risk in precipitating and perpetuating each TMD symptom by the use of its confidence interval to define significance. RESULTS: The incidence of TMD symptoms ranged from 6.1% (TMJ pain) to 12.9% (TMJ noise). More than half of the subjects who had reported TMJ and neck pain at the initial survey no longer reported these symptoms at the second survey, whereas TMJ noise and shoulder stiffness remained in more than 70% of the subjects. Individuals under 40 years old had a 3.3:1 increased risk of precipitating TMJ noise (P < 0.01), individuals with a history of extrinsic trauma had a 2.85:1 increased risk of precipitating limited mouth opening (P < 0.01), and females had a 2.81:1 increased risk of perpetuating TMJ pain (P < 0.01). CONCLUSION: The possible etiologic significance of these factors in TMD should be validated by future research.

Age Distribution↗

The long-term effect of occlusal therapy on self-administered treatment outcomes of TMD.

Because of a lack of substantial scientific data, the efficacy of occlusal therapy for the management of temporomandibular disorders (TMD) is still controversial. Of a total of 1405 consecutive TMD patients examined over the last 10 years, 369 (26.3%) were determined to have completed treatment at least 1 year before the present survey. A sample questionnaire was mailed to each patient in this sample population. The questionnaire failed to reach 46 patients; of the 323 patients who received the questionnaire, 260 (80.5%) responded. The mean duration of time between their last visit and this survey was 3.7 years. The questionnaire elicited information on treatment outcomes, present treatment needs, and current signs and symptoms. Participants were divided into two treatment groups: (a) those who underwent some occlusal therapies (Phase II) following successful reversible therapies (Phase I) (20 men and 114 women); and (b) those who underwent reversible therapy only (33 men and 93 women). Participants were further differentially diagnosed into five diagnostic subgroups of TMD, based on the clinical examination at the initial visit, tomography, and, for some patients, magnetic resonance imaging. The subgroups included myalgia, arthralgia, anterior disc displacement with an without reduction, and osteoarthritis/osteoarthrosis. Only 12.3% of the total population surveyed reported lack of improvement to an acceptable level and further need for treatment. The remaining patients reported satisfactory results in the reduction of TMD symptomatology and no further need for treatment, because their symptoms had either disappeared or improved to an acceptable level. Regardless of treatment groups and diagnostic subgroups, the current subjective signs and symptoms were negligible in most patients, and mean mouth openings were in the normal range. No particular diagnostic subgroups seemed to have significantly better outcome following Phase II occlusal therapy. These results suggest that the majority of TMD signs and symptoms improve to an acceptable level with only reversible therapy, and the long-term value of additional occlusal therapy following reversible therapy is minimal. Therefore, permanent occlusion-changing therapies apparently are not generally needed to maintain TMD symptom reduction over time.

Activities of Daily Living↗

Effect of skeleton size on the performance of octadecylsilylated continuous porous silica columns in reversed-phase liquid chromatography.

We prepared continuous porous silica rods that had silica skeletons with sizes of 1.0-1.7 microns and through-pores of 1.5-1.8 microns, and evaluated their performance as a column in reversed-phase liquid chromatography. The mesoporous silica monoliths (mesopore size: 14 or 24 nm) were derivatized to C18 phase by on-column reaction with octadecyldimethyl-N,N-diethylaminosilane. The C18 silica rods gave minimum plate heights of 10-15 microns for aromatic hydrocarbons in 80% methanol and of 20-30 microns for insulin in acetonitrile-water mixtures in the presence of trifluoroacetic acid. The performance of the silica rods at a high flow-rate was much better than that of conventional columns packed with 5 microns C18 silica particles with pores of 12 or 30 nm, especially for high-molecular-mass species. Silica rods with the smaller sized silica skeletons resulted in Van Deemter plots showing a minimum plate height linear velocity of the mobile phase and a smaller dependence of plate height on the linear velocity. Separation impedance of less than 1000 was achieved with the continuous silica columns. The higher performance and lower pressure drop of silica rods at high flow-rates compared with particle-packed columns is provided by the small silica skeletons and large through-pores.

Animals↗

An experimental study on intestinal vascular lesions: a comparison between the effects of arterial and venous occlusion in the acute phase.

In order to clarify what early ischemic changes are produced by venous interruption in the intestine, intestinal vascular lesions caused by peripheral venous ligation were compared with those caused by arterial ligation in rabbits. With less than 30 min ligation, there were only 4 specimens from a total 13 without injury following venous ligation, whereas there were 7 from a total 11 without injury following arterial ligation. After 30 min venous ligation, both the mucosal and submucosal layers of all 10 specimens were affected, while following arterial ligation, 3 of the 11 specimens showed no histological changes. Moreover, in 3 of the remaining 8 specimens from the latter group, the injury was confined to within the mucosal layer. Thus, in cases of venous interruption, intestinal injury might be evoked earlier with more severe damage than in cases of arterial interruption.

Acute Disease↗

Clinical trials of long-term RF local hyperthermia for advanced gastric cancer.

The effect of local hyperthermotherapy (HT) using 13.56-MHz radiofrequency (RF) capacitive heating was evaluated in 25 patients with unresectable or recurrent gastric cancer. HT was carried out once to 3 times a week for a duration of one hour at each session. Patients who underwent RF-HT frequently showed maintenance of performance status, symptomatic improvement and a reduction in tumor size. Moreover, the survival time of 9 patients who had numerous metastases to the distant peritoneum was significantly high (p less than 0.01), compared with 42 historical control patients who also had massive peritoneal dissemination, but had not received HT. The results of this study therefore indicate RF-HT to be a favorable modality in the palliative treatment of patients with far-advanced gastric cancer.

Adult↗

[Experimental and clinical studies of cefmenoxime in the field of obstetrics and gynecology].

The study group was organized to evaluate the usefulness of cefmenoxime (CMX) injection, a new synthetic cephalosporin, for the treatment of infections in the field of obstetrics and gynecology. Fundamental and clinical studies were made by the society and the following results were obtained. 1. The peak distribution of CMX's MIC for E. coli, Klebsiella sp., Enterobacter sp., Bacteroides sp. and Peptococcus sp. isolated from obstetrical and gynecological infections with relatively high frequencies area 0.1, less than or equal to 0.05, 0.2, 3.13, 1.56 micrograms/ml, respectively, with an inoculation of 10(6) cells/ml. 2. When 1 g of CMX is administered by intravenous drip infusion for 1 hour, the maximum concentrations in various tissues of female genital organs were as follows: 14.2 and 13.2 micrograms/g in ovary and oviduct, respectively, at 1.20 hours after the start of administration, and 16.9 and 26.3 micrograms/g in corpus uteri and cervix uteri, respectively, after 1 hour. As for the transfer to the exudate in the pelvic dead cavity, the peak concentration was 15.6 micrograms/ml after 2.13 hours. 3. In the clinical studies, CMX was given to 258 cases with female genital organ infections and others. As for the clinical effects, with exclusion of 3 cases in which other antibiotics are concomitantly used, responses were excellent in 76 cases, good in 162 cases and poor in 17 cases, among 255 cases in total. The efficacy rate was 93.3%. The efficacy rates by diseases were 97.1% (68/70) for intrauterine infections, 88.8% (79/89) for intrapelvic infections, 98.4% (62/63) for adnexitis, and 100% (23/23) for infections of external genital organs. As for the clinical effects on causative bacteria, the efficacy rates were 100% (19/19) for single infections due to Gram-positive bacteria, 94.8% (55/58) for single infections due to Gram-negative bacteria, and 88.2% (15/17) for single infections due to anaerobic bacteria. And its efficacy rates were 89.6% (69/77) for mixed infection cases. Side effects were observed in 2 cases (0.8%); 1 case with eruption, and 1 case with diarrhea and vomiting. As for abnormal laboratory findings, lower white blood cell count was observed in 2 cases and elevation of the values regarding hepatic functions in 9 cases. All cases were returned to the normal after the completion of the administration. Cefmenoxime showed a satisfactory clinical efficacy and a potent bacteriological effect in treatment of the infections in the field of obstetrics and gynecology, and it has been concluded that cefmenoxime will be useful addition to the antibiotics for the therapy of these infections.

Adolescent↗

[Effects of bromocriptine on FSH and LH secretion in women with euprolactinemic anovulation (author's transl)].

A few reports have been given that Bromocriptine effected not only on the hyperprolactinemic anovulations but also on the euprolactinemic anovulations. This study was performed to examine the underlying mechanism, 5 mg of Bromocriptine was daily administered for 30 days to 38 women with euprolactinemic anovulations. The basal secretions of FSH, LH and Prolactin and also the responsiveness to LH-RH, TRH and estradiol were examined. 31.6% of oligomenorrhea, anovulatory cycle and Ist. grade amenorrhea showed ovulatory cycles, however, no ovulations were observed in IInd. grade amenorrhea. The basal levels of FSH and LH significantly increased but the basal levels of Prolactin decreased by Bromocriptine. The responsiveness of FSH to LH-RH was markedly promoted but LH showed no significant change. Serum FSH was suppressed in estrogen loading test after Bromocriptine, which was poorly changed before. On the other hand, serum LH was markedly elevated by estradiol after Bromocriptine, which showed poor elevation before. These results conclude that: 1) Ovulation is induced by Bromocriptine administration in euprolactinemic anovulations. 2) Bromocriptine promotes the FSH and LH secretion from the pituitary and also promotes the reserve of FSH in the pituitary. 3) Bromocriptine promotes the sensitivity of the estrogen feedback in the hypothalamus.

Adolescent↗

Health effects of acrylonitrile in acrylic fibre factories.

The relationship between the degree of exposure and biological effects of acrylonitrile (AN) was studied in 102 workers whose exposure period exceeded five years, and in 62 matched controls, all of whom had been randomly sampled from six acrylic fibre factories in Japan. The six factories were classified into three groups on the basis of AN concentration at workplaces. The most highly exposed group of subjects showed an eight-hour average AN concentration of 4-2 ppm by personal sampling, a mean urinary AN concentration of 360 microgram/1 and a mean urinary thiocyanate concentration of 11-4 mg/1. Medical examination, including the indocyanine green excretion test and multiple clinical chemistry determinations, failed to detect any health effect attributable to AN. Slight liver damage may possibly occur in more highly exposed workers. Urinary AN and thiocyanate determinations may provide more accurate estimates of low-grade exposure (less than 5 ppm).

Acrylonitrile↗