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Biomedical subjects

R Watanabe

Publications and source records attributed to R Watanabe.

At least 127 records · Page 7Linked to original sources
PubMed1998

Quick responses of plasma amino acid concentration to changes in dietary amino acid levels in rats.

In order to evaluate the availability of plasma amino acid (AA) concentration as a parameter to determine AA requirements of rats within a short period, the response of the plasma AA concentration to changes in dietary AA levels was studied. In Experiment 1, to clarify whether the plasma AA concentration responded to changes in dietary AA levels and how long the response of the plasma AA concentration was maintained, 10 male rats were fed a casein diet for a 7 day period, and then the food was changed to AA diets. The serine (Ser), glycine (Gly) and threonine (Thr) levels were decreased from 120, 90 to 60% of the casein diet at 7-day intervals successively. Blood samples were taken at 2, 4 and 7 days after changing the diet, from the vena caudalis by vein puncture. In all cases, the plasma AA concentration responded to changes in dietary AA within 2 days, and the response was maintained until the 7th day. Experiment 2 was conducted to confirm that the plasma concentration of each AA responded to the changes in dietary AA levels at the first day and the responses of the plasma concentration of AA were maintained until the 4th day after changing the dietary AA levels, when the combination of metabolically unrelated AA was added. Five rats in A groups were fed diets with added arginine + Thr, histidine + methionine, lysine or isoleucine + Ser, and five rats in B groups were fed diets with added Gly + valine, leucine + phenylalanine or Thr + tyrosine + valine for a 4-day period successively. Blood samples were taken at 1 and 4 days after changing diets. Although the plasma concentrations of histidine, leucine, methionine, phenylalanine and Ser did not respond to changes in dietary AA levels, those of other AA responded at 1 day and the responses were maintained until the 4th day.

Amino Acids, Essential↗
PubMed1998

Familial hemiplegic migraine with irreversible brain damage.

Familial hemiplegic migraine (FHM) is an autosomal dominant syndrome characterized by recurrent episodes of varying degrees of hemiparesis associated with migraine. The aura including hemiparesis may be prolonged and in severe attacks may often be associated with confusion or coma. We describe a case of FHM whose aura was atypically prolonged and resulted in irreversible brain deficit which on magnetic resonance imaging (MRI) was suggestive of cortical hyperperfusion. A subsequent MRI showed left brain atrophy.

Adult↗
PubMed1998

[Severe hepatic veno-occlusive disease (VOD) which was successfully treated with supportive therapy, but subsequently developed late-recurrence].

A 40-year-old man with chronic myelogenous leukemia in chronic phase received an allogeneic marrow graft from his HLA identical brother. He was conditioned with busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg). Graft-versus-host disease (GVHD) prophylaxis was attempted with cyclosporine A (CYA) and methotrexate. On day 30, weight gain, ascites and hepatomegaly developed in addition to an elevation of total bilirubin (TB). He was diagnosed as having veno-occlusive disease (VOD) and treated conservatively. The TB level increased up to 20.1 mg/dl on day 66, then reduced to 2.1 mg/dl on day 129. By that time ascites and hepatomegaly also had completely resolved. However, on day 134. The TB level started to increase again, when the lesions of chronic GVHD were observed in the eye, the mouth, and the skin. CYA was started on day 142, and FK506 was substituted for CYA on day 161. Despite the improvement of oral and skin lesions, TB level continued to rise, and he died of respiratory failure due to ARDS on day 186. Autopsy revealed both acute and old hepatic VOD lesions, suggesting the occurrence of late-onset VOD which probably contributed to the liver dysfunction observed after clinical resolution of the first episode of VOD.

Adult↗
PubMed1998

[A case of autosomal dominant, pure form spastic paraplegia with thinning of the corpus callosum].

Autosomal dominant hereditary spastic paraplegia (HSP) is genetically classified into three types, all of which are characterized by insidiously progressive spasticity of the lower extremities. Patients with a complicated form of autosomal recessive HSP associated with hypoplasia of the corpus callosum have been reported by Iwabuchi et al. Here we report a 64-year-old patient with a pure form of autosomal dominant HSP with thinning of the corpus callosum. He had been well until 12 years of age, when spasticity and weakness of the lower extremities began to develop. His symptoms gradually worsened and he had difficulty in walking at the age of 44. When he was 56 years old, he visited our hospital. Eleven family members over five generations have been affected, and anticipation, i.e., an apparent decrease in age of onset, has been observed. On admission, he had mild cataracts, equinovarus and pes cavus, and neurological examination revealed spastic paraplegia. However, the intelligence test was normal, and nystagmus, ataxia of the extremities, involuntary movement, orthostatic hypotension or urinary disturbance was not observed. Trinucleotide repeat diseases, such as Huntington's disease, spinocerebellar ataxia type 1, spinocerebellar ataxia type 2, Machado-Joseph disease and dentatorubral-pallidoluysian atrophy, were excluded by DNA analysis. Brain MRI at the age of 64 revealed marked thinning of the corpus callosum. We considered this patient had a pure form of HSP. However, thinning of the corpus callosum has never been reported in autosomal dominant HSP.

Adolescent↗
PubMed1997

Apoptosis in human leukemic cells induced by lactoferricin, a bovine milk protein-derived peptide: involvement of reactive oxygen species.

We examined the activity of bovine lactoferricin (Lfcin-B), a peptide derived from a bovine milk protein lactoferrin (LF-B), to induce apoptosis in THP-1 human monocytic leukemic cells. Treatment with Lfcin-B at up to 50 micrograms/ml induced cell death in THP-1 cells in dose- and time-dependent manner, showing apparent morphological changes, hypodiploid forms of genomic DNA and apoptotic DNA fragmentation, whereas LF-B was inactive even at a high dose (500 micrograms/ml). The apoptosis-inducing effect of Lfcin-B increased with reduction of serum concentration, but was inhibited by addition of Zn2+, a inhibitor of Ca2+/Mg(2+)-dependent endonucleases in a dose-dependent manner. Furthermore, Lfcin-B-induced apoptosis in THP-1 cells was completely abolished by addition of antioxidants such as N-acetyl-L-cysteine (NAC) and glutathione (GSH), but not by various cytokines and mitogen which can activate monocytic cells. In addition, THP-1 cells treated with Lfcin-B, but not LF-B, showed high levels of intracellular reactive oxygen species (ROS) from the early period (20 min) of Lfcin-B treatment. And the production of ROS by Lfcin-B was dependent upon the dose of Lfcin-B added. These results suggested that Lfcin-B, a LF-B-derived peptide, but not LF-B itself, is able to induce apoptosis in THP-1 human monocytic tumor cells, and that its apoptosis-inducing activity is related to the pathway mediated by production of the intracellular ROS and activation of Ca2+/Mg(2+)-dependent endonucleases.

Acetylcysteine↗
PubMed1997

Unique sequence and lesional tropism of a new variant of neuropathogenic friend murine leukemia virus.

FrC6 murine leukemia virus (MuLV) is a replication-competent, neuropathogenic variant derived from Friend MuLV (F-MuLV) complex. The A8 virus (a molecular clone of the FrC6 virus) induced marked spongiform degeneration in the brain similar to the FrC6 virus, but only mild lesions were found in the spinal cord. In contrast, PVC211 virus, which is also a neuropathogenic F-MuLV variant, caused marked spongiform degeneration in the spinal cord. Virus recovery from the spinal cord of A8 virus-infected rat was the same as that of PVC211-infected rat, indicating that there is no direct correlation between the titer of virus and the intensity of lesions. Furthermore, rats infected with the A8 virus at 3 weeks of age did not undergo spongiform degeneration, although recovery of high titer of virus occurred in the central nervous system (CNS). Studies using chimeric viruses between the A8 virus and nonneuropathogenic F-MuLV clone 57 also indicated that the sequences responsible for virus titers in the CNS and neuropathogenicity are different. The chimeric virus studies proved that the env gene and the LTR and/or 5' leader sequence of A8 are critical for the induction of neuropathogenicity. These sequences in A8 and PVC211 were compared, focusing in on the sites that account for neurovirulence and viral lesional tropism.

3T3 Cells↗
PubMed1997

Expression cloning of PIG-L, a candidate N-acetylglucosaminyl-phosphatidylinositol deacetylase.

Many eukaryotic cell surface proteins are bound to the cell membrane by a glycosylphosphatidylinositol (GPI) anchor. Several genes involved in GPI anchor biosynthesis have been cloned using complementation of mutant mammalian cell lines and yeasts that are defective in its biosynthesis pathway. However, the gene involved in the second step of this pathway, in which N-acetylglucosaminyl-phosphatidylinositol (GlcNAc-PI) is N-deacetylated to form glucosaminyl (GlcN)-PI, has not been cloned. In this study, we established a GPI anchor-deficient mutant of Chinese hamster ovary (CHO) cells defective in the second step. Complementation analysis with the known GPI anchor mutant cells demonstrated that it belonged to the same complementation group as the CHO cell mutant G9PLAP.85. Using the new mutant, we cloned a rat gene termed PIG-L (for phosphatidylinositol glycan class L) that is involved in this step. PIG-L encodes a 252-amino acid, endoplasmic reticulum membrane protein, most of which is in the cytoplasmic side. This orientation of PIG-L protein is consistent with the notion that the second step of GPI anchor biosynthesis occurs on the cytoplasmic side of the endoplasmic reticulum.

Amidohydrolases↗
PubMed1997

Gastric inhibitory polypeptide activates MAP kinase through the wortmannin-sensitive and -insensitive pathways.

The signal transduction pathways of a cloned human gastric inhibitory polypeptide (GIP) receptor have been investigated in CHO cells stably expressing this receptor. Exposure of GIP receptor expressing cells to GIP significantly increased MAP kinase activity. Time course analysis showed that a rapid and marked increase in MAP kinase activation was detected and that this activation reached maximal levels 10 min after the addition of GIP. Dose-response analysis showed that GIP activated MAP kinase activity in a dose-dependent manner with an ED50 value of 5.9 x 10(-10) M of GIP. Wortmannin, a potent inhibitor of phosphatidylinositol 3-kinase (PI3-kinase), partially inhibited GIP-induced MAP kinase activation, suggesting that GIP activates MAP kinase through two different, wortmannin-sensitive and -insensitive pathways. It has been demonstrated that in CHO cells cAMP attenuates MAP kinase activity by inhibiting Raf-1. Since GIP elevates intracellular cAMP, we examined the effects of cAMP on MAP kinase activation. Interestingly, forskolin, which increased intracellular cAMP levels, significantly inhibited MAP kinase activation by GIP, but did not affect MAP kinase activation by GIP in the presence of wortmannin, suggesting that the wortmannin-sensitive pathway activates an MAP kinase cascade at or above the level of Raf-1 and that the wortmannin-insensitive pathway activates an MAP kinase cascade below the level of Raf-1. These findings demonstrate that the GIP receptor is linked to the MAP kinase cascade via at least two different pathways.

Androstadienes↗
PubMed1997

Alternative splicing of the erythropoietin receptor gene correlates with erythroid differentiation in rat hematopoietic and leukemic cells.

An alternative splicing of the rat erythropoietin receptor (EpoR) gene was identified in normal and erythroleukemia cells. A 105 bp insert was found at a region corresponding to the extracellular domain of EpoR. The alternative transcript was translated to a soluble EpoR (EpoR-S) expressed in spleen, bone marrow, and cultured erythroleukemia cells in addition to the full-length EpoR (EpoR-F). One of the rat erythroleukemia sublines, K4DT, which partially lost erythroid phenotypes and manifested monocyte/macrophage characteristics also lacked EpoR-S expression. Thus, expression of EpoR-S may play an important role in differentiation of rat erythroid cells.

Alternative Splicing↗
PubMed1997

Impaired NO release from bovine aortic endothelial cells exposed to activated platelets.

We have previously shown that aggregated human platelets elicited a decrease in intracellular adenosine triphosphate (ATP), enhanced adenosine egress and damage to mitochondria in bovine aortic endothelial cells (ECs). To test whether such metabolic and ultrastructural changes could be associated with functional impairment of ECs, we investigated the effects of activated platelets on nitric oxide (NO) and prostacyclin release, and on the antiaggregation property of ECs. Pretreatment of ECs with aggregated platelets transiently stimulated basal NO release while prolonged (> or = 30 min) exposure dose-dependently inhibited NO release, both basal and in response to ATP or serotonin, with NO synthase activity being attenuated in these cells. Supplementary L-arginine (L-A) restored NO release completely. Prostacyclin release was also stimulated transiently but not affected by prolonged pretreatment. The antiaggregation property of ECs was attenuated by pretreatment with activated platelets but restored with L-A supplement. Although the effects of activated platelets and 0.5 mM acetylsalicylic acid (ASA) to attenuate the antiaggregation property of ECs were additive, activated platelets had no effect on ECs treated with 0.2 mM N omega-nitro-L-arginine (L-NA), suggesting a common mechanism. We conclude that prolonged exposure to aggregated platelets may affect the antiaggregation property of ECs by directly inhibiting NO synthesis, which may be normalized by L-A supplementation.

Adenosine Triphosphate↗
PubMed1997

Cervical spinal cord compression in hereditary multiple exostoses. Report of a case and a review of the literature.

Spinal cord compression is an extremely serious complication of hereditary multiple exostoses (HME). A case of HME with compression of the cervical spinal cord is reported. Complete recovery following surgery was achieved. A review of the relevant literature revealed 51 previous cases of HME with cord/cauda equina compression. Most patients were under 30 years of age with more men affected than women. The family history was positive in 60%. The cervical and thoracic areas were predominantly affected, with the symptoms usually developing slowly. Recovery following surgery is to be expected in the majority of cases. In patients with HME and suffering from neurological symptoms, the possibility of spinal cord compression should be considered. Prompt diagnosis and surgical excision provide the best prognosis.

Adolescent↗
PubMed1997

Cervical myelo-radiculopathy in athetoid cerebral palsy.

Cervical myelopathy complicating athetoid cerebral palsy has not been adequately highlighted in the literature. We report two cases of patients with athetoid cerebral palsy and long histories of involuntary movements who developed cervical myelo-radiculopathy. Dystonic athetoid neck movements may cause excessive axial neck rotation as well as flexion and extension movements of the spine. These repetitive exaggerated movements may result in early degenerative changes of the vertebrae which may enhance the myelo-radiculopathy. The two patients were treated with combined anterior and posterior fusion with satisfactory results. They were bedridden preoperatively but have since started walking with or without a cane. We conclude that combined anterior and posterior fusion is the treatment of choice for severe myelopathy complicating athetoid cerebral palsy.

Adult↗
PubMed1997

Immunohistochemical distribution of cutaneous fatty acid-binding protein in human skin.

Cutaneous fatty acid-binding protein (C-FABP) has been newly discovered from rat skin. The immunohistochemical study revealed that C-FABP is strongly expressed in rat epidermis. Recently, a highly homologous protein to rat C-FABP was found in psoriatic epidermis, which is termed psoriasis-associated fatty acid-binding protein (PA-FABP). In the present study, we investigated the expression of PA-FABP in normal and pathological human skin using immunohistochemical techniques. In normal skin, PA-FABP was expressed in basal and prickle cell layers, and more strongly in the granular cell layer. The expression pattern of PA-FABP was similar to that of C-FABP in rat skin. In psoriatic skin, PA-FABP was expressed in suprabasal layers and more strongly in more differentiated keratinocytes. In squamous cell carcinoma, PA-FABP showed very strong expression in squamous nests. These results indicate that PA-FABP is a human homologue of C-FABP. Moreover, it is suggested that C-FABP has important roles in the transport and metabolism of fatty acids in epidermis and that altered lipid metabolism may affect the proliferation and/or differentiation of keratinocyte.

Amino Acid Sequence↗
PubMed1997

GM-CSF- and IL-3-dependent CD34 expressing myeloid cell line (SAS-1) established from CD7 and CD34 expressing acute myeloblastic leukemic cells.

A novel factor-dependent human myeloid leukemia cell line (SAS-1) was established from a 69-year-old Japanese male suffering from CD7 and CD34 expressing acute myeloblastic leukemia (AML M2 in FAB classification). Morphological and cytochemical staining showed that SAS-1 cells were round with basophilic cytoplasm which is positive for peroxidase. Analysis of surface markers revealed that SAS-1 cells were myeloblasts derived from an immature progenitor origin, which express CD34. The consensus karyotype of the cell line was 41 XY 5q-, -7, 11p-, 12p+, -13, -14, -16, -17, -19, -22, with two markers. The proliferation of SAS-1 cells was dependent on the presence of either granulocyte-macrophage colony-stimulating factor (GM-CSF) or interleukin-3 (IL-3), and GM-CSF- and IL-3-induced proliferation was dose dependent. Neither, stem cell factor (SCF) nor granulocyte colony-stimulating factor (G-CSF) alone supported the growth of SAS-1 cells, but supported their viability for more than 4 days and arrested them in the G0/G1 phase. SCF also enhanced GM-CSF- or IL-3-induced growth, but other cytokines did not have this synergistic effect. Clonogenic assays revealed that SAS-1 cells formed 36.0 +/- 5.7 or 41.5 +/- 0.7 colonies/1000 cells in the presence of GM-CSF or IL-3, respectively. SCF also increased the number of colonies formed by GM-CSF or IL-3 treatment, while SAS-1 cells did not form colonies in the presence of SCF alone. SAS-1 cells may prove to be a useful tool for studying the regulation of the cell cycle, myeloid proliferation, and differentiation.

Aged↗
PubMed1997

Bovine lactoferrin and lactoferricin, a peptide derived from bovine lactoferrin, inhibit tumor metastasis in mice.

We investigated the effect of a bovine milk protein, lactoferrin (LF-B), and a pepsin-generated peptide of LF-B, lactoferricin (Lfcin-B), on inhibition of tumor metastasis produced by highly metastatic murine tumor cells, B16-BL6 melanoma and L5178Y-ML25 lymphoma cells, using experimental and spontaneous metastasis models in syngeneic mice. The subcutaneous (s.c.) administration of bovine apo-lactoferrin (apo-LF-B, 1 mg/mouse) and Lfcin-B (0.5 mg/mouse) 1 day after tumor inoculation significantly inhibited liver and lung metastasis of L5178Y-ML25 cells. However, human apolactoferrin (apo-LF-H) and bovine holo-lactoferrin (holo-LF-B) at the dose of 1 mg/mouse failed to inhibit tumor metastasis of L5178Y-ML25 cells. Similarly, the s.c. administration of apo-LF-B as well as Lfcin-B, but not apo-LF-H and holo-LF-B, 1 day after tumor inoculation resulted in significant inhibition of lung metastasis of B16-BL6 cells in an experimental metastasis model. Furthermore, in in vivo analysis for tumor-induced angiogenesis, both apo-LF-B and Lfcin-B inhibited the number of tumor-induced blood vessels and suppressed tumor growth on day 8 after tumor inoculation. However, in a long-term analysis of tumor growth for up to 21 days after tumor inoculation, single administration of apo-LF-B significantly suppressed the growth of B16-BL6 cells throughout the examination period, whereas Lfcin-B showed inhibitory activity only during the early period (8 days). In spontaneous metastasis of B16-BL6 melanoma cells, multiple administration of both apo-LF-B and Lfcin-B into tumor-bearing mice significantly inhibited lung metastasis produced by B16-BL6 cells, though only apo-LF-B exhibited an inhibitory effect on tumor growth at the time of primary tumor amputation (on day 21) after tumor inoculation. These results suggest that apo-LF-B and Lfcin-B inhibit tumor metastasis through different mechanisms, and that the inhibitory activity of LF-B on tumor metastasis may be related to iron (Fe3+)-saturation.

Animals↗
PubMed1997

A human gall-bladder signet ring cell carcinoma cell line.

To date, very few reports of the establishment of gall-bladder cancer cell lines have appeared, although many cancer cell lines of various kinds have been established. On the other hand, no reports could be found on signet ring cell carcinoma cell lines derived from the gall-bladder and only five cell lines from the stomach. A human gall-bladder cancer cell line (FU-GBC-2) was established in tissue culture from the ascitic fluid of a 69-year-old Japanese female patient. The tumor cells growing in tissue culture exhibited the morphological characteristics of signet ring cells in phase contrast and electron microscopy. The population doubling time was 43 hours. Heterotransplantation was succeeded by inoculation into the dermis of BALB/c nude mice. An immunocytochemical study showed that most of the cultured cells were positive for carcinoembryonic antigen, CA19-9 and epithelial membrane antigen, but negative for vimentin. The modal chromosome number was 120 with a range of 100-124. Flow cytometry showed an aneuploidy pattern in the cultured cells at passage 30. Markedly amplified c-myc oncogene was observed by Southern blot analysis. This cell line may be useful in the study of the morphological and biological characteristics of signet ring cell carcinoma and gall-bladder adenocarcinoma.

Aged↗
PubMed1997

Retroperitoneal laparoscopic adrenalectomy for functioning adrenal tumors: comparison with conventional transperitoneal laparoscopic adrenalectomy.

PURPOSE: We attempted to confirm the possibility and feasibility of laparoscopic adrenalectomy via the retroperitoneal approach, and to compare results of the transperitoneal and retroperitoneal approaches. MATERIALS AND METHODS: Three men and 8 women (mean age 39.6 years) with functioning adrenocortical tumors (primary aldosteronism in 5 and Cushing's syndrome in 6) underwent laparoscopic adrenalectomy via the retroperitoneal approach using a balloon dissection technique and a newly developed ultrasonic aspirator. Results were compared to those of 27 cases of transperitoneal laparoscopic adrenalectomy. RESULTS: Although the retroperitoneal approach was successful in all 5 patients with primary aldosteronism, it succeeded in only 2 of the 6 cases of Cushing's syndrome. In 3 Cushing's syndrome cases the retroperitoneal approach was changed to the transperitoneal laparoscopic approach due to difficulty in exploration. Open laparotomy was required in 1 case of left Cushing's syndrome because of an inadvertent pancreatic injury. Subcutaneous emphysema developed in 6 patients without hypercapnia or prolonged postoperative symptoms. Mean operative time and blood loss, and time to oral intake and ambulation were 248.3 minutes, 151.4 ml., and 1.55 and 2 days, respectively. There was no difference between retroperitoneal and conventional transperitoneal laparoscopic adrenalectomy in regard to these factors or to convalescence. CONCLUSIONS: Retroperitoneal laparoscopic adrenalectomy is feasible for primary aldosteronism. However, Cushing's syndrome is presently a much more difficult indication than primary aldosteronism for this new operative technique.

Adrenal Cortex Neoplasms↗