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Biomedical subjects

H Kumazawa

Publications and source records attributed to H Kumazawa.

At least 55 records · Page 3Linked to original sources
PubMed1991

[Long-term results of congenital dislocation of the hip treated with Pavlik harness].

We have studied congenital dislocation and subluxation of the hip reduced by Pavlik harness with long-term roentgenographic results and prognostic factors. Eighty dislocations and thirty-five subluxations were assessed by X-ray. Average age at final follow-up was 17 years (14 to 23 years). Anatomical healing (Group I of Severin's classification) was 61.2% in dislocation and 71.5% in subluxation. Avascular necrosis of the femoral head was 7.0% (8 hips) and deformity was mild. Acetabular dysplasia appeared to be an important factor in determining the prognosis. In cases with both satisfactory and unsatisfactory results, the acetabular development differed from that of the normal cases from early childhood. After 11-12 year old the acetabular development normalized in cases with satisfactory results but did not in those with unsatisfactory results. Factors influencing the results were not clarified, there was the strong relationship between affected side and unaffected side in Center-Edge angle of Wiberg, Sharp's angle, AAQ (Approximate Acetabular Quotient) and Severin's classification respectively. This study concluded that long-term results of congenital dislocation and subluxation of the hip reduced by Pavlik harness were not always satisfactory and were strongly influenced by endogenous acetabular development in our cases.

Acetabulum↗
PubMed1990

[Aerodynamics of respiratory flow in the nasopharynx].

The authors present a new technique for studying airflow patterns and particle deposition in the nasopharynx. The nasal cavities and the nasopharynx from the head of a human cadaver were filled with siliconrubber and a "positive" model was then produced by moulding with plastic. An apparatus was constructed to provide calibrated flow of propandiol in both directions. Flow characteristics were visualized by introducing small particles in suspension or by injecting methylene blue with a needle. In addition, test aerosol was drawn in through the model to demonstrate dust deposition sites in the nasopharynx. In the future, this method will enable us to examine the nasopharyngeal airflow patterns and deposition sites of inhaled particles.

Airway Resistance↗
PubMed1989

Use of the subrenal capsule assay to measure antibody-dependent, cell-mediated cytotoxicity against head and neck tumors.

Experience with antibody-dependent, cell-mediated cytotoxicity (ADCC) has shown that antibody can increase the localization and killing capacity of lymphocytes. We tested the possibility of improving the activity of lymphokine-activated killer cells (LAK) on human tumor using the subrenal capsule assay in nude mice. The tumors were first grown in the renal capsule space and the effector cells injected later. In the model experiment we used M21 melanoma and monoclonal antibody against melanoma-associated antigen GD3. This antibody increases the tumor inhibitory activity of LAK cells from healthy donors in comparison to LAK alone. We have been able to prove the clinical relevance of such an approach. Tumor bioptic material from five tumor patients was tested with various monoclonal antibodies, following which the highly reactive antibodies were selected and incubated with the patient's LAK cells. Such pretreated LAK cells have a high growth-inhibitory effect on autologous tumor growing in the renal capsule space of the test mice.

Animals↗
PubMed1989

The anti-tumor effect of in vitro tumor-stimulated autologous peripheral blood lymphocytes measured by the subrenal capsule assay.

Lymphokine-activated killer cells (LAK) are able to kill natural killer (NK)-resistant fresh bioptic tumor cells. We have tried to increase the antitumor activity of peripheral blood lymphocytes by the simultaneous stimulation with interleukin-2 and autologous tumor extract (TE). The influence of LAK cells and LAK cells stimulated with TE was compared in the subrenal capsule assay in nude mice. Experiments were performed with eight head and neck tumors following their surgical extirpation. The tumors were first grown in the renal capsule space while lymphocytes were being stimulated in vitro. Following this, the lymphocytes were injected into the growing tumors. The autologous TE-stimulated LAK cells were more effective in treating tumors than were the LAK cells. Tumors regressed in some cases so treated, a finding which was never observed with LAK cells alone.

Animals↗
PubMed1989

Adenocarcinoma and carcinoid developing spontaneously in the stomach of mutant strains of Mastomys natalensis.

Neoplastic and nonneoplastic lesions developing spontaneously in antral and fundic mucosae of stomachs of mutant chamois-coloured Z (130 animals) and Y (67 animals) strains of Mastomys aged 18 to 24 months were examined histologically and histochemically. The Z strain developed both antral lesions (hyperplasia 29.2%; dysplasia 23.8%; adenocarcinoma 17.7%) and fundic carcinoid(s) (72.3%). The antral lesions were limited to the lesser curvature near the pyloric ring. Macroscopically, adenocarcinomas resembled human gastric carcinomas of either Borrmann's type I or II. Histochemically, adenocarcinoma cells were characterised by marked reduction of total mucins produced and predominance of mucins with both periodic acid-Schiff and Alcian blue reactivities (neutral and sialated class II mucins). An infiltrating adenocarcinoma was successfully transplanted into nude mice, reaching the 7th generation of transplantations over 4 years, and retained histological features of the primary tumour. The ultrastructural appearance of growing transplanted tumours supported the reduced production of mucins by adenocarcinoma cells with scarcity of mucin granules and intracellular cysts. However, the Y strain never developed antral lesions like the wild strain, developing fundic carcinoid(s) only. Microscopically, these carcinoids contained argyrophilic nonargentaffin granules, and biochemically produced histamine consistently but no 5-hydroxytryptamine (5-HT, serotonin) like those of the wild strain. Since we found unexpectedly that a line of F2 but not F1 hybrids between wild and Z strains developed the same antral lesions as Z strain, a preliminary experiment was performed to confirm the development of antral lesions in F2 hybrids newly produced by brother-sister mating. Among 41 surviving F2 offspring, 4 (9.8%) developed hyperplasia, 2 (4.9%) dysplasia and none adenocarcinoma. The numbers (6) of animals observed with these lesions approximated to their expected numbers (7.3).

Adenocarcinoma↗
PubMed1989

Growth of single proglottides during early adult development of Hymenolepis nana.

The growth of individual proglottides of Hymenolepis nana has been studied by measuring the width and length of the proglottides between days 3 and 8 post-infection in mice. Two sets of measurements were obtained. The first involved proglottides immediately posterior to the point of proglottis formation and proglottides at particular stages of development. For the second set, measurements were made of proglottides at certain positions in the worm, specifically the 20th, 100th and 200th proglottides, as counted from the posterior end of the worm. For proglottides at different stages in development, the width of a particular stage was greater in the later days of infection, while the length was almost constant. The length of newly-formed proglottides varied only slightly with time despite differences in the width and in the 3-fold increase in proglottis production that occurs between days 3 and 8 post-infection. The width of the 20th, 100th and 200th proglottides followed parallel growth curves that coincided with each other after an appropriate shift along the time axis. The more anterior the position of the proglottis, the greater was the width at the time of proglottis formation, and so its growth began later on the common growth curve. Growth in length of the 20th proglottis was at first faster than the 100th and 200th proglottides, but later slowed down to a level comparable with them, and the growth curves for the length of the three proglottides were very similar to each other. The rates of growth in the volume of the three proglottides were also estimated. The results are also discussed in relation to other approaches to the study of tapeworm growth and to factors that may be responsible for the growth patterns observed.

Animals↗
PubMed1989

[Initial results of immunotherapy approaches to tumor treatment in the animal model].

The possibilities of using immunocytes in cancer therapy have been increasing during the last few years. Contrary to the promising results gained by in vitro experiments, several clinical trials have shown that, on the one hand, it is difficult to preserve a quantity of cells big enough to inhibit tumours, and they have also shown that, on the other hand, antitumour lymphocytes do not get into the tumour. That is why we concentrated on improving the tumour selectivity of the antitumour lymphocytes. We carried this out practising two sets of experiments. First we incubated patient lymphocytes with tumour extract and vaccinated them in this manner. Secondly, by binding antitumour antibodies to lymphocytes, we could improve the ability of lymphocytes to bind with tumour cells. We tested these therapy models on human tumours and on tumour cell lines. Both were implanted in the renal capsule space of nude mice.

Adenocarcinoma↗
PubMed1988

Participation of autonomic nerve in tonsillar focal infection.

Participation of the autonomic nerve in tonsillar focal infection was investigated by measuring neurotransmitters, receptors and microvibration. In focal infection patients, the volume of norepinephrine in the tonsil increased significantly and the number of a-adrenergic receptors decreased. These findings suggest that the focally infected tonsil exhibits a high degree of sympathetic nerve activity. The ratio of N-type in microvibration decreased systematically, which indicates some imbalance or immaturity of the autonomic nervous system in focal infection patients. Based on this data, the production mechanism of tonsillar focal infection was speculated from the point of view of the autonomic nerve.

Autonomic Nervous System↗
PubMed1987

CT findings of aspergillosis in the paranasal sinuses.

The diagnosis of aspergillosis in the paranasal sinuses is preoperatively difficult to make in spite of the increasing number of reports showing its prevalence. However, because symptoms are usually non-diagnostic and infection is usually confined to a single sinus, X-ray findings are often suspect for possible neoplasm. We have studied six patients with aspergillosis, all of whom were suspected of having sinus tumors, but were otherwise healthy persons. Affected sinuses were examined by CT and the diagnosis of non-invasive aspergillosis was confirmed by operation. In this report, we have compared the CT and X-ray findings in our cases of aspergillosis. These findings indicate that CT is useful in the preoperative diagnosis of sinus aspergillosis.

Aged↗
PubMed1987

[Study on the preoperative adjuvant therapy of cancer--relation between serum and tumor tissue levels of UFT and OK-432 after administration, and skin reactions to Su-polysaccharide (Su-Ps)].

This study was carried out with 48 patients received surgery, i.e., 23 stomach cancer, 8 colon cancer, 6 rectal cancer, 9 breast cancer etc. Patients in group A received UFT in combination with OK-432. Each of UFT or OK-432 was given to the patients in groups B or C, respectively. Changes in the skin reaction to Su-PS were measured before and after dosing, and concentrations of Tegafur and 5-FU in serum and tumor tissues were determined after administration. Analysis of the skin reaction to Su-Ps revealed that patients with positive skin reaction before surgery in group A didn't manifest depression due to sensitization by UFT therapy. Although average values of the skin reaction after dosing were slightly lower compared to those before dosing in group B, sensitization was effective. Values of the skin reaction after dosing were significantly (p less than 0.05) high compared to those before dosing in groups A and C. Concentrations of Tegafur and 5-FU in serum reached to the peak 2 hr later and were maintained high enough to expect clinical responses even at 4 hr after administration in groups A and B. Especially there was not a significant difference between groups A and B in tumor tissue levels of 5-FU, and a high effective concentration was obtained. Combination therapy of UFT with OK-432 exhibited no significant interaction between them in adjuvant immuno-chemotherapy, and satisfactory results were expected in clinical cures.

Adult↗