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Biomedical subjects

Y Chiba

Publications and source records attributed to Y Chiba.

At least 253 records · Page 14Linked to original sources

Antigenic variation of human RSV strains isolated in Japan.

Antigenic variations of respiratory syncytial virus (RSV) strains were analyzed using a collection of nine, seven, two, and one monoclonal antibodies (MAbs), respectively, raised against the fusion protein (F), large glycoprotein (G), nucleoprotein (NP), and phosphoprotein (P) components of the Long strain of RSV. Competitive binding assay by these MAbs demonstrated eight, four, and two distinct epitopes on F, G, and NP components, respectively. Comparison of prototype Long with ten field strains isolated in Sapporo, Japan, during a 9-year period from 1980 to 1988 by radioimmunoprecipitation (RIP), immunofluorescence (IF), and enzyme-linked immunosorbent assay (ELISA) test revealed four different patterns of reaction to these MAbs. Thus, prototype Long reacted to all 19 MAbs. Six field strains have shown a different reactivity to one of nine anti-F and to one of seven anti-G antibodies (subgroup A). Three of the remaining isolates failed to react with three of nine anti-F and with all of seven anti-G antibodies (subgroup B). One strain (58-104) isolated in 1983 was similar to subgroup A except for a lack of reaction with two anti-G antibodies. All field strains reacted with two anti-NP and one anti-P antibodies. The numbers of altered epitopes in subgroup A were 1/8 and 1/4; in subgroup B, 3/8 and 4/4; and in 58-104, 1/8 and 2/4 on the F and G components, respectively. No other variations have been observed among field isolates tested.

Antibodies, Monoclonal↗

Development of cell-mediated cytotoxic immunity to respiratory syncytial virus in human infants following naturally acquired infection.

With virus-infected autologous and allogenic mononuclear cells as specific targets, the development of cell-mediated cytotoxic reactivity to respiratory syncytial virus (RSV) was studied in peripheral blood lymphocytes (PBL) in groups of infants with acute RSV infection and in other control groups of subjects during a community outbreak of RSV infection. No RSV-specific cellular cytotoxicity was observed in cord blood lymphocytes and in other uninfected controls. The PBL of infants with acute RSV infection exhibited significant cellular cytotoxic response. The activity peaked early, usually within 1 week after infection. The response appeared to be age-dependent. Over 65% of infants 6-24 months of age and about 35-38% of infants under 5 months of age exhibited cellular cytotoxicity to RSV. Cellular cytotoxic reactivity was observed against autologous and less frequently against allogenic RSV-infected target cells. These findings suggest the appearance of virus-specific cell-mediated cytotoxic immune response after acute RSV infection. The development of cellular cytotoxic responses may play a role in the mechanisms of protection against or the pathogenesis of RSV infection in man.

Adolescent↗

Prevention of vertical transmission of hepatitis B virus by yeast recombinant hepatitis B vaccine.

In order to prevent vertical transmission of hepatitis B virus (HBV), yeast recombinant HB vaccine at a dose of either 5 mcg or 10 mcg was administered to 185 infants born to mothers who were positive for HBs antigen (HBsAg). All of them developed antibody to HBsAg (anti-HBs) after three vaccinations. Generally, the cut-off index (COI) of anti-HBs by radioimmunoassay (RIA) was higher in the 10 mcg dosage group than in the 5 mcg dosage group. The geometric mean titer (GMT) of anti-HBs, as measured by quantitative RIA, in the former group was 2.4 times that in the latter one month after the third vaccination. The incidence of clinical reactions was only 4% in a total of 561 injections, and none of the reactions were severe. It is concluded that recombinant HB vaccine is safe and has excellent immunogenicity for infants requiring prevention of HBV vertical transmission. It is also suggested that 10 mcg doses of the recombinant HB vaccine can provide more solid protection to high-risk infants without serious adverse reactions.

Carrier State↗

Immunoglobulin A antibody response to respiratory syncytial virus structural proteins in colostrum and milk.

Immunoglobulin A (IgA) antibody response to respiratory syncytial virus (RSV) structural proteins in colostrum and milk was investigated by a radioimmunoprecipitation assay. By using [35S]methionine-labeled RSV-infected HEp-2 cells and antiserum to human IgA as the capture antibody, IgA antibody responses to large glycoprotein, fusion protein, nucleoprotein, phosphoprotein, and matrix protein were demonstrated in colostrum and milk. The IgA antibody response was mainly directed against fusion protein, whereas IgA activity against matrix protein was more variable and was not comparable to the antibody responses to other structural proteins. Maternal mammary IgA response after RSV infection in the infant was monitored in four cases, and the appearance of anti-RSV IgA activity against several RSV structural proteins was observed in convalescent-stage milk samples of two mothers in whom RSV infection was demonstrated.

Antibodies, Viral↗

Cordectomy for syringobulbo-myelia with sleep apnea secondary to a spinal extramedullary tumor: case report.

The case of a 40-year-old man with syringobulbo-myelia secondary to an unresectable spinal extramedullary tumor is described. Fifteen years previously, the patient had undergone a laminectomy of T8 through T12 for a "benign" spinal cord tumor at another hospital and had become paraplegic; the tumor (neurinoma) had been neglected for 12 years. Magnetic resonance imaging demonstrated a large thoracolumbar spinal tumor with syringobulbo-myelia. Polysomnography showed central-, peripheral-, and mixed-type sleep apneas. After the failure of an attempted syringoperitoneal shunt, cordectomy at the level of T6 was performed with a good result. The mechanisms of the formation of syringomyelia and sleep apnea secondary to a caudal spinal extramedullary tumor are discussed.

Adult↗

Effects of neuromedin B on insulin and glucagon release from the isolated perfused rat pancreas.

The effect of neuromedin B (NMB) on insulin and glucagon release was studied in isolated perfused rat pancreas. Infusion of NMB (10 nM, 100 nM and 1 microM) did not affect the insulin release under the perusate conditions of 5.5 mM glucose plus 10 mM arginine and 11 mM glucose plus 10 mM arginine, although 10 nM NMB tended to slightly suppress it under the perfusate condition of 5.5 mM glucose alone. The degree of stimulation of insulin release provoked by the addition of 5.5 mM glucose to the perfusate was not affected by the presence of 10 nM NMB. The glucagon release was slightly stimulated by the infusion of 100 nM and 1 microM NMB but not by 10 nM NMB under the perfusate condition of 5.5 mM glucose plus 10 mM arginine. The effect of C-terminal decapeptide of gastrin releasing peptide (GRP-10) was also examined and similar results were obtained; 10 nM and 100 nM GRP-10 did not affect insulin release and 100 nM GRP-10 stimulated glucagon release under the perfusate condition of 5.5 mM glucose plus 10 mM arginine. The present results concerning glucagon release are consistent with the previous results obtained with isolated perfused canine and porcine pancreas. However, the results regarding insulin release are not. Species differences in insulin release are also evident with other neuropeptides such as substance P and the mechanism of such differences remains for be clarified.

Animals↗

Establishment of the specific radioimmunoassay for serum thymic factor (STF).

Serum thymic factor is a humoral factor involved in the differentiation of T cells. In the present study, a radioimmunoassay system for STF was established using a specific antiserum and an iodinated synthetic STF as a tracer. Serum levels of STF-like immunoreactivities were around 30 pg/ml in human, but in contrast to previous reports serum STF levels did not show age-dependent decreases. STF-like immunoreactivities of the thymic gland were lower than those of the liver and kidney in rats. The livers of human and pig contained high STF-like immunoreactivities. The rat thymic gland extract showed three peaks of STF-like immunoreactivity by gel filtration of Sephadex G-25 which corresponded to the eluted position of authentic STF, a larger molecular size, and a smaller molecular size of STF, respectively, while the rat liver extract showed two peaks corresponding to the void volume fraction and to the position of authentic STF, respectively. When this void volume fraction was digested by trypsin, three peaks which corresponded to authentic STF, a larger molecular size, and a smaller molecular size of STF were observed. Present studies suggest that serum thymic factor is produced as a larger STF molecule in the liver and kidney.

Adult↗

An eight year experience with gradually longer interval postremission therapy for adults with acute leukemia.

Between January 1980 and March 1983, a study was conducted into the effects of postremission therapy on 20 patients with acute leukemia who had achieved complete remission through induction therapy. Postremission therapy consisted of cyclic administration of six combination therapies given at gradually longer intervals. Postremission therapy used DCMP (D, daunorubicin; C, cytosine arabinoside; M, 6-mercaptopurine; P, prednisolone), DCyMP (Cy, cyclocytidine), DCVP (V, vincristine), BHAC-DMP (BHAC, behenoyl-ara-c), BHAC-AMP (A, aclarubicin) and ACM-MP (ACM, aclacinomycin). Six combinations were given sequentially starting at one month interval, and then at 2, 3, 4, 5 and eventually 6 month intervals until 5 year survival was reached. The median remission duration was 38 months for acute myelogenous leukemia (AML), and 17 months for acute lymphoblastic leukemia (ALL). The median survival was 66 months for AML, and 33 months for ALL. The survival rate at 5 years was 60% for AML., 40% for ALL, and 50% in all 20 patients. Methotrexate and prednisolone were administered intrathecally for prophylaxis of CNS leukemia on Day 4 of each stage of postremission therapy. There was no CNS leukemia. This postremission therapy was shown to be effective in improving the prognosis of adults with acute leukemia.

Acute Disease↗

Late infection after cranioplasty--review of 14 cases.

The incidence of late infection after cranioplasty was studied in 130 patients with 133 cranioplasties. The materials used were prefabricated resin in 62 cases, autogenic bone in 38, intraoperatively fashioned resin in 25, and vitallium in eight. Six infections were documented, for an infection rate of 4.5%. In addition to these six cases, we studied eight patients with infections who had undergone cranioplasty elsewhere but had the infected plates removed in our hospitals. Among the 14 cases of infection, the intervals between cranioplasty and plate removal were 3 to 43 months (average, 10.5 months). The eight patients referred from other hospitals had a significantly shorter average interval between external decompression and cranioplasty than did patients who did not develop infection (2.6 versus 6.7 months; p less than 0.005). Systemic signs were mild despite obvious local signs of infection. Of the 11 first infections, nine (82%) were associated with discharge of pus from a fistula; in these cases a galeal suture had become infected apparently through scratching by the patients. In contrast, in the three patients who had had a previous infection, the second infection manifested as subgaleal and epidural empyema or meningitis without a fistula or pus discharge. Nine infections (69%) were due to Staphylococcus. All but two patients required removal of the infected plates. One recovered with conservative therapy and one died of meningitis, giving a mortality rate of 0.8%. No matter how mild the systemic signs, late infection warrants surgical debridement and plate removal. The risk factors for late infection of cranioplasty are discussed.

Adolescent↗

Thermosensitive determination of patency in lumboperitoneal shunts. Technical note.

Surface cooling and thermistor recording over shunt tubing was used in 23 studies of cerebrospinal fluid shunt patency in 19 patients with lumboperitoneal shunts and normal-pressure hydrocephalus. Shunt patency was shown by downward reflection of the recording trace similar to that obtained for ventriculoperitoneal shunts. Obstruction was demonstrated by a flat-line recording or an upward deflection.

Body Temperature↗

[Aging and reference values of the parameters in optokinetic nystagmus].

Changes in optokinetic nystagmus by age were assessed, and preparation of reference values by age was made by the use of the data from 834 reference subjects. As a result, changes by age were observed at the test on optokinetic nystagmus. The reference values by these changes can be approximated with the quadratic and was considered, therefore, to be useful clinically. Four parameters were set for the test items for optokinetic nystagmus as the total number of nystagmus (NYS); the mean of eye velocity during the fast phase of nystagmus (FM); the algebraic summations of eye velocity (VEL) and amplitude (AMP) during the slow phase of nystagmus. As the process for statistical analysis, variables were divided into 7 groups, and after removing outlier (any extraneous data) in each group, changes in variables by age were assessed by the one-way analysis of variance and the method of multiple comparison (Ryan's method). As a result: 1) the age group of each variable seemed to develop into normal distribution; 2) it was presumed that change in NYS by age is less; 3-1) regarding FM, VEL and AMP, no change was observed in the variable by ages on 30s and 40s; and 3-2) however, decrease in the measured value was observed in ages on 60s along with aging. From these, the ages on 50s are the generation when the measured values of optokinetic nystagmus change. On the other hand, the reference values calculated, taking age into consideration, could be approximated with the quadratic.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Giant cell pneumonia caused by varicella zoster virus in a neonate.

A premature male neonate, born at the 25th gestational week, developed pneumonia six days after delivery and died. Postmortem examination of the lungs revealed giant cell pneumonia with intranuclear inclusion bodies; varicella zoster infection was confirmed by immunoperoxidase stain using monoclonal antibody to varicella zoster virus and electron microscopic examination. In previously reported necropsy cases of numerous giant-cell formation in the lung is not mentioned. Therefore, the unusual features prompting this report include the absence of skin lesions in this mother and infant and the presence of giant cell pneumonia, not previously reported in varicella zoster infection.

Antibodies, Monoclonal↗

[Clinical evaluation of imipenem/cilastatin sodium against severe infections complicated with hematological disorders and solid tumors].

Imipenem/cilastatin sodium (IMP/CS) was administered to patients with severe infections complicated by hematological disorders and solid tumors to assess its efficacy and safety. Primary diseases in this series of 76 cases included 37 cases of hematological disorders (acute leukemia in 25 cases, malignant lymphoma in 7 cases, aplastic anemia in 3 cases and 2 other diseases) and 38 cases of solid tumors (lung cancer in 7 cases, gastric cancer in 11 cases, esophageal cancer in 6 cases, pancreatic cancer in 3 cases, bile duct cancer in 4 cases, hepatocellular cancer in 3 cases, and 4 other diseases). Following results were obtained. 1. Types of infection in hematological diseases were sepsis in 5 cases, suspected sepsis in 24 cases, pneumonia in 5 cases and 3 others. The efficacy rates were 100% in sepsis, 62.5% in suspected sepsis, 80% in pneumonia and 73% in all cases. 2. Types of infection in solid tumors were sepsis in 2 cases, suspected sepsis in 13 cases, pneumonia in 10 cases, cholecystitis in 2 cases, cholangitis in 5 cases, liver abscess in 2 cases, and 4 others. The efficacy rates were 50% in sepsis, 69.2% in suspected sepsis, 80% in pneumonia, and 71.1% in all cases. 3. IPM/CS was administered in single use in 66 cases and in combination with other antibiotics in 9 cases. The efficacy rate in the single use was 72.7% and that in the combination use was 66.7%. 4. The efficacy rate in 35 cases of first use was 71.4% and that in 40 cases of second use was 72.5%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Acute myelomonocytic leukemia with inv (16) (p13 q22) disappeared abnormal karyotype during complete remission].

A 21-year-old man was admitted to our hospital because of anorexia and general malaise in July, 1988. On admission, the white blood cell count of 18,600/microliters with 72% leukemic cells. The bone marrow aspirate showed 76.8% immature monocytes, 10% mature and immature eosinophils. Leukemic cells were 66.6% myeloperoxidase positive cells, and 20.6% naphthylbutyrate esterase positive cells. The lysozyme activity in urine was high. Cytogenetic analysis revealed the presence of 46 XY inv (16) (p13 q22). Under the diagnosis of acute myelomonocytic leukemia with eosinophilia (M4Eo) associated with inv (16) (p13 q22), one course of DCMP induction therapy was performed. After complete remission, the bone marrow aspirate showed disappearance of inv (16) (p13 q22), and associated with decreased residual leukemic cells.

Adult↗

[An intensification therapy of adults acute leukemia].

Between January 1980 and March 1983, a study was conducted on the effects of intensification therapy in 20 adult acute leukemia patients who had achieved complete remission with induction therapy. Intensification therapy consisted of cyclic administration of six combination therapies given at gradually longer intervals, using daunorubicin, cytosine arabinoside, 6-mercaptopurine and prednisolone (DCMP), cyclocytidine (DCyMP), vincristine (DCVP), behenoyl-ara-c (BHAC-DMP), aclacinomycin (BHAC-AMP) and (ACM-MP). Six combinations were given sequentially at one-month intervals, at 2-, 3-, 4-, 5- and eventually 6-month intervals, until 5-year survival. The median remission duration was 38 months for AML, and 17 months for ALL. The median survival was 66 months for AML, and 37 months for ALL. The five year survival rate was 50%. Nine of the 20 patients are still alive. Methotrexate and prednisolone were administered intrathecally for prophylaxis of CNS leukemia on Day 4 for each intensification therapy. There was no CNS leukemia. This intensification protocol was shown to be effective in improving the prognosis of adults acute leukemia.

Acute Disease↗