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Biomedical subjects

H Okawa

Publications and source records attributed to H Okawa.

At least 55 records · Page 3Linked to original sources
PubMed1997

[A case of jugular foramen neurinoma originating from glossopharyngeal nerve].

A 39-year-old man was admitted with right hearing loss, tinnitus and vertigo. Neurological examination on admission revealed right facial palsy, right acoustic nerve disturbance and cerebellar ataxia. CT scan demonstrated a mass with intra-and extracranial extension in the pyramid bone concomitant with enlarged jugular foramen. MRI showed a ring-like enhanced, extra-axial mass in the right CP angle. Cerebral angiography showed no tumor stain. Venous phase of VAG revealed lateral displacement of the right sigmoidal sinus and obstruction of the internal jugular vein. Three dimensional CT was very useful to reveal enlarged jugular foramen. The tumor was resected totally and was approached through a right suboccipital craniectomy and mastoidectomy on July, 1994. Surgery confirmed that the tumor was a neurinoma originating from the glossopharyngeal nerve. After the operation, right facial palsy developed and transient fugitive CSF leakage was observed, but the patient is doing well. There was no amelioration of right hearing loss. JFN originating from the glossopharyngeal nerve is rare. Twenty-five cases of glossopharyngeal neurinoma are reviewed.

Adult↗
PubMed1996

Analysis of the CDR3 region of the rearranged IgH chain genes in patients with severe combined immunodeficiency and severe lymphopenia.

Human B cell-negative severe combined immunodeficiency (B-SCID) is a primary immunodeficiency disease characterized by both T and B lymphocytopenia and agammaglobulinemia. Although lymphocytes of B-SCID patients express defective recombinase activity and rarely succeed in making Ag receptors, the molecular defect of the human B-SCID remains to be identified. To gain more insight into the human B-SCID defect and its effect on the Ab repertoire, we examined the Ig heavy (H) chain genes of the peripheral blood leaky B cells from three B-SCID patients. Although the number of B cells in their peripheral blood was very limited, we could obtain 41 productive VDJ recombinations from the 58 joints. The recombinations showed a grossly altered pattern characterized by short N nucleotides, short deleted nucleotides from 5' JH segments, immature JH and D segment utilization, absence of VDDJ recombination, and all but one JH segment equal to germline JH segments. Therefore, Ab repertoire of IgH chain gene in human B-SCID was limited because of restricted junctional and combinatorial diversity and few somatic mutations. Furthermore, unusually long P nucleotides were inserted in junctional sequences, which might indicate that resolution of hairpin is impaired in human B-SCID as in the murine SCID.

B-Lymphocytes↗
PubMed1996

Decreased alpha/beta heterodimer among CD8 molecules of peripheral blood T cells in Wiskott-Aldrich syndrome.

Cell surface CD8 molecules exist as either alpha/alpha homodimers or alpha/beta heterodimers, and most CD8+ T cells that undergo differentiation in the thymus express alpha/beta heterodimers. CD8 molecules on peripheral blood lymphocytes of patients with Wiskott-Aldrich syndrome (WAS), an X-linked immunodeficiency disease, have now been shown to be composed mostly of alpha/alpha homodimers, while the total number of lymphocytes was maintained. This observation may indicate aberrant differentiation of CD8+ T cells in the thymus of WAS. Decreased CD8alpha/beta heterodimer expression, and the relative increase of CD8+ T cells expressing CD8alpha/alpha homodimer, may explain a part of the defective lymphocyte functions in WAS patients.

Aging↗
PubMed1995

T cell reconstitution by haploidentical BMT does not restore the diversification of the Ig heavy chain gene in patients with X-linked SCID.

We previously examined the Ig heavy (H) chain gene of pretransplant patients with X-linked SCID (XSCID), having defects in the gene of the IL-2 receptor (R) gamma chain. In the present study, we analyzed two post-transplant XSCID patients, in whom T cell-depleted haploidentical BMT resulted in lymphoid split chimeras, i.e., donor functional T cells coexisting with recipient B cells. Although the recipient B cells produced IgM, no isohemagglutinin or Ag-specific Ab was detected. To investigate the cause of failure to produce Ab in the patients, we sequenced the complementarity determining region 3 (CDR3) and adjacent region of Ig H chain gene, which govern Ab specificity. Among the 64 post-transplant CDR3 junctional sequences, combinatorial and junctional diversity were normal compared with those in age-matched controls. All of the post-transplant joining regions except one clone were equal to germline and the frequency of somatic mutation was significantly lower than that in age-matched controls. The results indicated that T cell reconstitution by BMT does not restore diversification of the Ig gene in the IL-2R gamma chain-deficient B cells, which might be associated with the defect in the Ag-specific Ab production.

Base Sequence↗
PubMed1994

Preferential utilization of the immature JH segment and absence of somatic mutation in the CDR3 junction of the Ig H chain gene in three X-linked severe combined immunodeficiency patients.

Human severe combined immunodeficiency (SCID) includes an X-linked SCID (XSCID) characterized by a complete absence of mature T cells, hypogammaglobulinemia and a normal or elevated number of B cells. XSCID results from mutation in the IL-2 receptor (IL-2R) gamma chain gene, which is thought to be involved in not only IL-2R but also IL-4R and IL-7R mediated signals. To investigate the VDJ recombination and Ig repertoire development in the absence of the IL-2R gamma chain, we intended to study the CDR3 junction in peripheral blood B cells of three XSCID patients. A total of 101 different CDR3 junctions were cloned following polymerase chain reaction amplification of polyclonal peripheral blood lymphocyte DNA. Sequence analysis of CDR3 junctions revealed that the primary antibody repertoire of the Ig H chain gene was assembled in a normal fashion. Among the JH segments, overexpression of JH3 segments was significant in XSCID patients compared with age-matched controls. D segment usage in XSCID was very similar to that in age-matched controls. All of the XSCID JH regions except for two clones were equal to germline JH genes, showing little or no evidence of somatic mutation. The results indicate that the immature JH segment is preferentially utilized and somatic mutation is absent in the CDR3 junction of the Ig H chain gene of XSCID patients.

B-Lymphocytes↗
PubMed1994

Human cytomegalovirus DNA in cerebrospinal fluid.

To determine the involvement of human cytomegalovirus (CMV) in conditions of neurological impairment, detection of CMV DNA was attempted in cerebrospinal fluid obtained from 45 neurologically affected children aged from 1 month to 17 years by means of the polymerase chain reaction. Four patients (congenital CMV encephalopathy with West's syndrome, acute encephalitis, chronic epileptic encephalopathy, and lissencephaly) had CMV DNA in their cerebrospinal fluid. CMV DNA was absent in the cerebrospinal fluid of 11 neurologically unaffected controls aged from 1 month to 11 years. Three patients with acute CMV hepatitis had no CMV DNA in their cerebrospinal fluid. Among the four patients who had CMV DNA in their cerebrospinal fluid, two did not excrete CMV DNA or CMV antigen in the urine. The possible pathogenetic significance of CMV DNA in the cerebrospinal fluid is discussed. By applying the polymerase chain reaction to cerebrospinal fluid, the mode of brain invasion by CMV can be clarified further.

Adolescent↗
PubMed1994

Pulmonary miliary tuberculosis and T-cell abnormalities in a severe combined immunodeficient patient reconstituted with haploidentical bone marrow transplantation.

We report the development of miliary tuberculosis in a 7-year-old boy with severe combined immunodeficiency (SCID), whose immune system had been only partially reconstituted by haploidentical bone marrow transplantation. Although alpha beta and gamma delta T cells were of donor origin, alpha beta T cells in this patient showed defective interleukin-2 (IL-2) production, impaired IL-2 responsiveness and decreased cytolytic activity. However, gamma delta T cells could exhibit enough cytolytic activity after incubation with IL-2. Despite the presence of disseminated infection, C-reactive protein (CRP) remained negative. IL-2 therapy aggravated the disseminated tuberculosis though gamma delta T cells were supposed to be activated, and concurrently CRP became positive. These findings suggest that gamma delta T cells have no more than limited immunological roles in mycobacterium tuberculosis infection.

Bone Marrow Transplantation↗
PubMed1994

[Effect of pirenzepine on gastric secretion during anesthesia and surgery].

Effect of pirenzepine on gastric secretion during anesthesia and surgery was evaluated in 46 surgical patients ranged in age from 18 to 68 years. The patients underwent orthopedic, ophthalmic, ENT, plastic or non-abdominal general surgery under neuroleptanesthesia except two patients who had enflurane or isoflurane anesthesia. They received either pirenzepine 10 mg, 20 mg or the combination of pirenzepine 10 mg and famotidine 20 mg intravenously just before the induction of anesthesia. Volume and acidity of gastric juice were measured for 3 hours after the administration of these agents. Decrease in volume and acidity of gastric juice after pirenzepine 10 mg as well as after pirenzepine 20 mg continued for more than 3 hrs after the administration of the agents. Efficacy of the combination of pirenzepine and famotidine on gastric secretion was more prominent than that of pirenzepine alone in a double dose.

Adolescent↗
PubMed1993

A case of appendiceal mucocele showing massive mucous production with concomitant colonic cancer.

A 58-year-old male patient presented with abnormal discharge of 200 ml transparent fecal mucus. Irregular protuberance of the ascending colon into the adjacent ileocecal region was observed by colonofiberscopy, and a cystic lesion in the ileocecal region was suggested by computerized axial tomography. Pale yellowish semitransparent jellied substances were observed exudating from the site of ileocecal resection. The diagnosis established was moderately differentiated colonic adenocarcinoma and a mucocele of the appendix. The mucus discharge disappeared after resection. Biochemical analysis of the mucus suggested the mucocele as a source of the discharged mucus. We report an extremely rare case of mucocele of the appendix that may be related to the cause of mucous stool.

Adenocarcinoma↗
PubMed1992

Signal transduction by interleukin 2 in human T cells: activation of tyrosine and ribosomal S6 kinases and cell-cycle regulatory genes.

The early events of signal transduction associated with interleukin-2 (IL-2) binding to its receptor were examined using a human IL-2 dependent T-cell line, Kit225. Cell cycle analysis showed that 90% of Kit225 cells were in the G0/G1 phase after a 72-hr incubation in the absence of exogenous IL-2. At this point, stimulation of the cells with IL-2 resulted in the rapid initiation of RNA and DNA synthesis by 9 and 20 hr, respectively. Within 5 min after addition of IL-2, rapid activation of tyrosine and ribosomal S6 kinases was detected. Addition of IL-2 also increased mRNA levels for c-fos, c-myc, IL-2 receptor alpha, and IL-2 receptor beta chain. These events increased in the absence of detectable changes in free cytosolic [Ca2+]i, inositol phosphate metabolism, or the activity of several kinases including cAMP-dependent protein kinase, Ca2+/calmodulin-dependent protein kinase, or protein kinase C. These findings demonstrate that the signals triggered by IL-2 binding to its receptors are quickly transduced into the nucleus with increased mRNA transcription of activation-associated genes. Furthermore, the data indicate that tyrosine and ribosomal S6 kinases may be important for IL-2-induced cell growth.

Calcium↗
PubMed1992

Primary hepatocellular carcinoma with severe hypoglycemia: involvement of insulin-like growth factors.

We report a case of severe hypoglycemia and hepatic masses suspected to be an insulin-like growth factor-II (IGF-II)-producing hepatocellular carcinoma. A 62-year-old man presented with mental disorder in the night and early morning associated with extremely low blood sugar levels (less than 21 mg/dl). Computerized axial tomography and ultrasonography revealed a massive tumor in the right lobe of the liver with multiple secondary nodules, and a tumor thrombus in the portal vein. At autopsy 107 days after admission, the liver weighed 3070 g, histologically showing an Edmondson type II tumor with liver cirrhosis. IGF-II in plasma (899 ng/ml) and tumor tissue (2.4 micrograms/g) was higher than that in normal plasma (374-804 ng/ml) and non-tumor liver tissue (0.2 micrograms/ml), while IGF-I (14 ng/ml) was significantly reduced. IGF-II, probably produced by the liver tumor, appeared to be involved in the mechanism of hypoglycemia.

Carcinoma, Hepatocellular↗