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Biomedical subjects

S Morikawa

Publications and source records attributed to S Morikawa.

At least 163 records · Page 9Linked to original sources
PubMed1992

Long-term follow-up of vascularized bone grafts for the reconstruction of tibial nonunion: evaluation with computed tomographic scanning.

Ten cases of reconstruction of the tibia with vascularized bone grafts were evaluated by computed tomographic (CT) scanning. In all cases the grafts were placed because of pseudarthrosis. The patients ranged in age from 20 to 64 years. The duration of follow-up was 1-9 years. In six cases fibular grafts were used to bridge the defect and in four cases iliac crest grafts were used. No additional bone grafts were placed after the initial operation. The pseudarthroses were classified into three types: type N--no bony defect (4 cases); type P--partial bony defect (3 cases); and type C--complete segmental bone loss (3 cases). Our evaluation showed that the grafts used to treat the type N and type P pseudarthroses were the same shape and size as at the time of placement. The grafts used to treat the type C pseudarthroses were hypertrophied, although the medullary canal of the graft remained the same size as at the time of placement. Hypertrophy was a result of an extraperiosteal reaction. The fibular grafts were square rather than triangular in cross section. It was concluded that mechanical loading is important in promoting hypertrophy of the graft.

Adult↗
PubMed1992

The suppressive effect of deoxyspergualin on the differentiation of human B lymphocytes maturing into immunoglobulin-producing cells.

Deoxyspergualin, an analog of spergualin, has been known as a novel immunosuppressive agent with strong immunosuppressive activity in in vivo experimental systems. In the present study, we examined the effect of deoxyspergualin (DSG) and methyldeoxyspergualin (MeDSG) on the proliferation and differentiation of human B lymphocytes in vitro. Highly purified B cells from human tonsil samples were isolated by Percoll density gradient from nonrosetted cells and were used as target cells. Both agents had little effect on the proliferative response of resting or activated B lymphocytes. However, they suppressed the immunoglobulin synthesis of B lymphocytes not only in a T cell-dependent, but also in a T cell-independent system. The inhibition of antibody synthesis was manifested in the early stage of B cell differentiation. Both drugs also suppressed Ig secretion, but not proliferation, of an EBV-transformed human B lymphoblastoid cell line. These results indicate that DSG and MeDSG have a selective immunosuppressive effect on the differentiation pathway of B lymphocytes.

Antibody-Producing Cells↗
PubMed1992

The distinct effects of FK506 on the activation, proliferation, and differentiation of human B lymphocytes.

We examined the effect of FK506 on the activation, proliferation and differentiation of human B lymphocytes in vitro. FK506 inhibited the proliferative response of resting B cells induced by Staphylococcus aureus Cowan strain I (SAC) and phorbol myristate acetate (PMA) in a dose-dependent manner. Inhibition of cell proliferation by FK506 was caused by a selective block of G0 to G1 phase transition leading to cell arrest. In addition, the proliferative response of in vivo-activated B cells and lymphokine-driven B cell proliferation were also found to be sensitive to FK506. Interestingly, FK506 did not affect the expression of activation antigens such as CD23, IL-2 receptor (CD25), and transferrin receptor (CD71). Finally, FK506 had little effect on B cell antibody generation in a T cell-independent system. Conversely, FK506 suppressed neither proliferation nor immunoglobulin secretion in a human B lymphoblastoid cell line. These results indicate that FK506 has discrete effects on the different stages of the B cell maturation.

Antibody-Producing Cells↗
PubMed1992

Degradation of streptomyces metalloprotease inhibitor (SMPI) by neutral protease from Bacillus subtilis var. amylosacchariticus.

The zinc-containing neutral endopeptidase (neutral protease: BANP) from Bacillus subtilis var. amylosacchariticus was inhibited by the proteinaceous metalloprotease inhibitor isolated from Streptomyces nigrescens (SMPI). The degree of inhibition was, however, significantly less than that for thermolysin (TLN). During incubation of BANP with SMPI, the inhibitor was proteolytically degraded and inactivated. Analysis of the digestion products suggested that a minor diversity in their substrate specificities between TLN and BANP affects the sensitivity to the proteinaceous metalloprotease inhibitor, SMPI.

Amino Acid Sequence↗
PubMed1992

Incidence of feline immunodeficiency virus reactive antibodies in free-ranging lions of the Kruger National Park and the Etosha National Park in southern Africa detected by recombinant FIV p24 antigen.

Lion sera from the Kruger National Park (KNP) dating back to 1977 and from the Etosha National Park (ENP), obtained from 1989 to 1991, have been analysed by ELISA and Western blot analyses using a genetically engineered antigen representing the p24 structural protein of feline immunodeficiency virus (FIV). It was concluded that some 83% of 98 KNP lion sera reacted with the p24 antigen, while none of 28 ENP lion sera reacted. A few other KNP felids (cheetahs and genets) gave samples that did not react with the FIV p24 antigen. For the KNP lions, apart from a lower prevalence in cubs (50%), no particular trends were demonstrated in terms of age, sex, date or origins of the samples. In Western blot and radio-immunoprecipitation analyses the lion sera reacted with the engineered p24 antigen, as well as with the p15 and p24 gag proteins and the p50 gag precursor protein from FIV, indicating that the agent is probably a lentivirus related to FIV. The ELISA with the engineered p24 antigen required less serum and appears to be more sensitive at detecting FIV-reactive antibodies than assays with available commercial kits.

Africa, Southern↗
PubMed1992

[Development of an experimental model for spontaneous lymph node metastasis of human esophageal carcinoma in nude mice--histopathological analysis].

Three human squamous cell carcinoma cell lines (HPL-EsC-1-K, -S, and -M) originated from a male patient with esophageal carcinoma were established and were studied on their tumorigenic and metastatic properties in nude mice. All cell lines grew in the hind foot pads following subcutaneous inoculation and produced popliteal lymph node metastasis dose (2-8 x 10(6)/mouse)-dependently. Based on the histopathological findings on serial sections of the lymph nodes, the stages of lymph node invasion by cancer cells were classified into 4 stages (St. 0-III). The time course of lymph node metastasis of EsC-K cells were examined. Advanced stage of metastasis increased according to the time elapsed after tumor cell inoculation. Incidence of metastasis of EsC-K cells were not affected by host factors such as sex differences, anti-asialo GM1 antibody treatment on the hosts. Today, there are few experimental models for studies on spontaneous lymph node metastasis of human carcinomas. This experimental model provides a useful research tool for studies on the biology and therapy for lymph node metastasis of esophageal cancer.

Animals↗
PubMed1992

[A case of severe juvenile pulmonary tuberculosis associated with malnutrition in special reference to nutritional assessment].

We reported a case who had suffered from severe pulmonary tuberculosis in association with severe malnutrition. A 19-year-old man was admitted complaining of high fever, productive cough and body weight loss. Before admission, he worked as a cook for long hours a day and had meals irregularly. On admission, he was cachexic. Coarse crackles were auscultated on the both lung field, and the liver was enlarged. Chest X-ray revealed multiple ringed and mottled shadows mainly in bilateral upper and middle lung field. Laboratory examination revealed inflammatory reaction defined by an increase of white blood cells, accelerated erythrocyte sedimentation rate and positive CRP, impairment of liver function and cell-mediated immunity, hypoxemia and restrictive lung dysfunction. Ziehl-Neelsen stain of sputum showed a large number of acid fast bacilli. The assessment of his nutritional status showed decrease in anthropometric measurements, visceral proteins and the Fischer ratio, which suggested that he was in the status of protein-calorie malnutrition in association with amino acid imbalance. He was treated with nutritional therapy in addition to antituberculous drugs, which improved his clinical symptoms, laboratory data and nutritional assessment. These results suggested the importance of nutritional assessment and nutritional therapy based on it.

Adult↗
PubMed1992

[A prospective study of psychosomatic reaction to hysterectomy].

Psychosomatic reaction to hysterectomy was prospectively studied by means of psychological tests and a questionnaire. One hundred and twenty patients who had simple hysterectomy were examined before and as long as one year after operation. The mean score for A-state, a state anxiety scale, was high before operation and rapidly declined postoperatively. SRQ-D and CMI, which represent depressive and neurotic states, respectively, showed rather high scores before and 2 weeks after operation. Mean scores in these psychological tests declined to a plateau within 6 months after operation, and there were less psychological and physiological symptoms and there was improved physical activity, showing that most patients can over come psychosomatic problems caused by hysterectomy. A close correlation was observed between the results of psychological tests and the number of psychological symptoms. Forty patients with a high SRQ-D score showed abnormality in other scales. Psychosomatic disorders associated with hysterectomy are characterized by various symptoms but mainly by a depressive state. High SRQ-D patients were divided into three subgroups: A) the SRQ-D score is constantly high, B) the SRQ-D is high for the first several weeks, and C) the score increased after discharge. Patients in each subgroup showed signs of a characteristic personality. These results show the presence of a different psychosomatic approach to the patients personally.

Anxiety↗
PubMed1992

[The study on intravesical instillation of THP in the treatment of in-situ and superficial bladder cancers].

The efficacy and safety of Pirarubicin (THP), administered by intravesical instillation, have been studied in recurrent multiple superficial bladder cancer patients and patients who tested positive by urine cytology but lacked protuberant legions (CIS). The average age and range of the 19 patients (M 15, F4) studied were 63.3 (37-84). Twelve patients had protuberant, multiple cancer and 7 patients had CIS. Sixteen of the cases were recurrent disease. Twenty mg THP, delufed in 40 ml of 5% glucose solution were instilled for 2 hours once or twice a week. Each patients received 8 treatments. One week after the last treatment, the therapeutic result was evaluated on the bases of cystoscopy and urine cytology. Before and after administration, CBC and biochemical blood tests were run. Nine of the 12 patients (75%) with multiple recurrent tumor and all the 7 patients with CIS showed complete response. The total outcome for CR was 84.2% in this study. Intravesical instillation with THP did not cause any serious side effects.

Administration, Intravesical↗
PubMed1991

In vivo oxygen-17 nuclear magnetic resonance for the estimation of cerebral blood flow and oxygen consumption.

To explore the feasibility of in vivo 17O NMR for the estimation of cerebral blood flow and oxygen consumption, in vivo 17O NMR spectroscopy and imaging were employed in animal models. In the spectroscopy, the changes in the 17O NMR signal intensity after the injection of H2(17)O and the inhalation of 17O2 gas were obtained every 4 seconds with sufficient signal-to-noise ratios for the quantification of cerebral blood flow and oxygen consumption. In the imaging, although the time and spatial resolutions were insufficient for the quantification of H2(17)O, 17O NMR images of rabbit brain could be obtained, indicating that it is possible to map cerebral blood flow and oxygen consumption by 17O NMR imaging.

Animals↗
PubMed1991

Effect of 17 beta-estradiol on the growth of an estrogen receptor-positive human esophageal carcinoma cell line.

Receptors for estrogen and for androgen in the nucleus and cytosol (ERn, ERc, ARn, and ARc, respectively) were studied on two newly established human esophageal carcinoma cell lines, ES-25C and ES-8C. ES-25C was ERn+ (the binding content 4.0 fmol/mg protein, Kd 0.09 nM), ERc-, ARn-, and ARc-. No receptors were found in ES-8C. Various doses of 17 beta-estradiol (E2) were added in vitro to investigate its effect on the growth of these cell lines. No effect of E2 was observed on ER--ES-8C cell line. The growth of ES-25C cell was significantly inhibited at the doses of 10(-10) and 10(-12) mol/l E2 compared with the control. The doubling time of 10(-12) mol/l E2-treated cells was 32 hours whereas that of control was 20 hours. This slower growth was reflected in the deduction of cells in S-phase utilizing 5-bromo 2'-deoxyuridine (BrdU) labeling. The current results strongly suggest that the growth inhibition of ER+ esophageal cancer cell by E2 is mediated by signal transduction induced by the estrogen-estrogen receptor system.

Aged↗
PubMed1991

[Ca++ antagonist and acute brain ischemia: effects of nilvadipine and nicardipine on middle cerebral artery occlusion in rats].

Effects of calcium antagonists, Nicardipine and Nilvadipine, on neurologic deficits and size of infarct were studied in the rat middle cerebral artery (MCA) occlusion model. Each drug was administered immediately after induction of ischemia, and neurologic grade was evaluated 1 to 24 hours after MCA occlusion. At 24 hours post-occlusion, size of the infarct was compared with that of the control group. In addition, evolution of cerebral infarction was studied at 6 hours and 12 hours post-occlusion by magnetic resonance imaging (MRI). In the Nilvadipine-treated group, neurologic deficits improved more rapidly and the size of infarct was significantly smaller than in the Nicardipine-treated group. MRI showed a progressive extension of cortical infarct in the untreated rat, whereas the infarct size remained unchanged in the Nilvadipine-treated rat. These results suggest the potential therapeutic usefulness of calcium antagonist for acute cerebral ischemia.

Acute Disease↗
PubMed1991

Energy metabolism of the liver in brain dead dogs assessed by 31P-NMR spectroscopy and arterial ketone body ratio.

The changes in hepatic energy state were assessed by 31P-nuclear magnetic resonance spectroscopy (31P-MRS) and arterial ketone body ratio (AKBR) in brain dead dogs. 31P-MRS and AKBR were measured before and at 3 hours after brain death. Wiggers' shock model was employed to compare the energy metabolism during hypotension. 1) The brain death model: Systemic blood pressure changed from 178.3/115.0 mmHg (mean) in the control period, to 259.5/162.5 mmHg during Cushing phenomenon (CU period) and to 63.3/51.7 mmHg after completion of brain death (BD period). beta-ATP/Pi increased from 1.27 +/- 0.14 (mean +/- SEM) to 1.46 +/- 0.16 in the early CU period, and then decreased to 1.11 +/- 0.15 at 60 minutes after BD, followed by a gradual increase to 1.33 +/- 0.13 at 3 hours after BD. Intracellular pH (pHi) increased alkaline to the control value. AKBR decreased from 1.10 +/- 0.26 to 0.46 +/- 0.15 in the CU period (p less than 0.05) and then increased to 1.48 +/- 0.25 after BD. 2) Wiggers' shock model: Systemic blood pressure was 190.0/112.5 mmHg in the control period, 83.8/51.3 mmHg during exsanguination (EX period) and 185.0/117.0 mmHg after retransfusion (RT period). beta-ATP/Pi decreased from 1.17 +/- 0.13 to 0.61 +/- 0.10 in the EX period (p less than 0.05) and increased to 1.37 +/- 0.08 in the RT period. The pHi deviated from 7.33 +/- 0.07 to 6.82 +/- 0.14 in the EX period (p less than 0.01) and to 7.51 +/- 0.21 in the RT period. AKBR decreased from 1.00 +/- 0.11 to 0.21 +/- 0.04 in the EX period and increased to 1.08 +/- 0.12 in the RT period. The energy metabolism of the liver was well maintained in the state of brain death in spite of remarkable hypotension, although that was not the case with Wiggers' shock model. It was suggested that the combination of 31P-MRS and AKBR was useful for the evaluation of graft liver viability.

Adenosine Triphosphate↗
PubMed1991

Sequences and coding strategies of the S RNAs of Toscana and Rift Valley fever viruses compared to those of Punta Toro, Sicilian Sandfly fever, and Uukuniemi viruses.

The sequences and coding strategies of the S RNAs of two viruses, Toscana (TOS) and the M12 derivative of Rift Valley fever ZH-548 (RVF, Phlebovirus genus, Bunyaviridae) have been determined from cDNA clones and compared to the previously published sequences of Punta Toro (PT), Sandfly fever Sicilian (SFS), and Uukuniemi (UUK) viruses. All five viruses exhibit an ambisense coding strategy for their small (S) RNA species, i.e., one gene product (the NSs protein) is encoded in the 5' half of the viral RNA, a second (the N protein) is encoded in the sequence complementary to the 3' half. The terminal nucleotides of the S RNAs of the five viruses are comparable through 13-14 residues. The 3' and 5' ends of these S RNAs have inverted complementary compositions. Three phleboviruses (TOS, SFS, and RVFV) exhibit comparable G-rich, centrally located intergenic sequences, albeit of different lengths. These sequences have a number of similar motifs at, or immediately following, the end of the coding regions, motifs that may be involved in their S mRNA transcription termination processes. The other two viruses (UUK, PT) have AT-rich intergenic sequences that have the potential to form secondary structure. They lack the G-rich sequences or particular sequence motifs recognized in the other three virus RNAs. The deduced sizes of the TOS and RVFV N proteins are 27,704 and 27,430 kDa (respectively). Their NSS proteins are 36,677 and 29,903 kDa (respectively). When aligned, the deduced sequences of the N proteins of the five viruses exhibit homologies ranging from 54 to 30%. The order of homology to RVFV N protein is PT greater than TOS greater than SFS greater than UUK; to TOS N protein it is PT greater than or equal to RVF greater than SFS greater than UUK. The sequences of the NSS proteins are less similar, with values ranging from 30 to less than 17%. The order of homology to RVFV NSS is SFS greater than PT greater than TOS greater than UUK. Due to these more distant relationships, the homologies to TOS NSS protein are less clear.

Amino Acid Sequence↗
PubMed1991

Analyses of the requirements for the synthesis of virus-like particles by feline immunodeficiency virus gag using baculovirus vectors.

Feline immunodeficiency virus (FIV) gag gene was expressed in baculovirus vectors to investigate its potential for the assembly of virus-like particles. The unprocessed 50-kDa FIV gag precursor made in infected insect cells by recombinant AcFIVGAG-1 was myristoylated, assembled at the cell surface into virus-like particles (with diameters of approximately 100 nm), and efficiently released into the culture supernatant fluids. The presence of the complete viral-coded protease component of the FIV pol gene engineered into a second expression vector (AcFIVGAG-P5) resulted in the efficient processing of the gag precursor to its component proteins and abolished particle formation and secretion. Insertion of a stop codon in this vector upstream of the putative gag-pol frameshift site (GGGAAAC) resulted in the derivation of an expression vector (AcFIVGAG-R) that made a truncated, unprocessed 46-kDa FIV gag precursor lacking some 34 amino acids in the p10 carboxy-proximal coding region of gag. This vector synthesized tubular structures in the cytoplasm of infected cells and released them into the cell supernatant. The results demonstrate that the FIV gag precursor can spontaneously assemble into virus-like particles without any other virus proteins and that the carboxy-terminal part of the precursor gag protein is essential for such assembly.

Animals↗
PubMed1991

Establishment of a novel cell line with T-lineage phenotype (HPB-MLp-W) from a non-Hodgkin's lymphoma patient.

We report the characterization of a novel human T-cell line, HPB-MLp-W, which was established from blastic cells of a lymph node specimen from a patient with non-Hodgkin's lymphoma. They demonstrated the T-cell association antigens, CD2 and CD4, but no CD3, CD8, CD1, CD5, CD7 nor T-cell antigen receptor on their cell surfaces. They were also positive for Ia and Ki-1 antigen, and negative for CD25 (Tac-1). The cell line HPB-MLp-W had the same pattern of antigen expression as the patient's cells. Southern-blot analysis of DNA showed a rearrangement of the T-cell receptor-alpha and beta genes. To our knowledge, this is a novel cell line with unique T-lineage marker, to be established from a case of non-Hodgkin's lymphoma.

Antigens, CD↗
PubMed1991

Identification of conserved and variable regions in the envelope glycoprotein sequences of two feline immunodeficiency viruses isolated in Zurich, Switzerland.

The nucleotide sequences of the envelope (env) coding regions of two strains of the feline immunodeficiency virus isolated in Zurich, Switzerland (FIVZ1, FIVZ2) have been analysed. In addition, the complete sequence of the FIVZ1 isolate has been determined. Comparisons have been made with the previously published sequences of three North American isolates (PPR and the Petaluma strains FIV34TF10 and FIV14). The isolate FIVZ1 was very similar to the Petaluma strains of FIV and may represent a clonal derivative acquired by 'contamination'. Overall there are between 2.6% and 15.1% amino acid changes in the env gene products of the five isolates. Of the Zurich isolates, FIVZ2 exhibited the greatest divergence to the other viruses and based on its genotype, phenotype and origins probably represents a new isolate of FIV. Possibly the viruses diverged only recently from a common ancestor. Some 31 of the 33 cysteine residues and 17 of the 21 potential N-linked glycosylation sites of the FIV34TF10 env gene product were conserved among all five isolates. The open reading frame 3 (ORF3, or D) which overlaps the env gene (but is encoded in a different frame) has an ATG codon downstream of a potential splice acceptor site in all five isolates, supporting the view that it encodes a viral gene product. In ORF3 of FIVZ1 a stop codon was located 16 amino acids upstream of the stop codon of ORF3 of the other isolates. The ORF4 (or G) of isolate FIVZ2, thought to be the second coding exon of an FIV rev-like gene, contained a nucleotide deletion in amino acid 45 of ORF4, resulting in a--1 frameshift at this position. Comparison of the LTR sequences of the five isolates identified conserved promoter/enhancer elements. A potential stem-loop structure was identified in the R region of the LTRs of all the isolates, despite the heterogeneity of nucleotide sequences in that region. Such structures (TAR) are present in analogous regions of other lentiviruses and are responsible for tat-mediated trans-activation.

Amino Acid Sequence↗