Biomedical subjects

Yasuhiro Watanabe

Publications and source records attributed to Yasuhiro Watanabe.

12 recordsLinked to original sources

PubMed2003

Role of hippocampal alpha(2A)-adrenergic receptor in methamphetamine-induced hyperlocomotion in the mouse.

Psychostimulants, such as methamphetamine (METH), induce psychological dependence and we recently suggested that hippocampal alpha(2A)-adrenergic receptor (alpha(2A)-AR) is involved in METH-induced modulation of central nervous systems. The present study shows that pretreatment with yohimbine dose-dependently decreased the ambulatory hyperactivities induced by METH (2 mg/kg) in mice. Moreover, specific knock-down of the hippocampal alpha(2A)-AR with infusion of anti-sense oligo DNA of alpha(2A)-AR significantly suppressed ambulatory activity induced by METH administration. Infusion of sense oligo DNA of alpha(2A)-AR into mouse hippocampus exerted no effects on the ambulatory activity. These observations strongly suggest the involvement of hippocampal alpha(2A)-AR in the regulation of ambulatory activity induced by METH administration.

Adrenergic Uptake Inhibitors↗

PubMed2003

Classification of congenital biliary cystic disease: special reference to type Ic and IVA cysts with primary ductal stricture.

Congenital biliary cysts occur not only in the choledochus but also everywhere in the biliary tree, and are frequently accompanied by pancreatobiliary malunion. Alonso-Lej and colleagues first classified choledochal cysts into three types, in 1959. Due to the recognition of intrahepatic involvement, we refined their classification into six types, in 1977, and this has become the reference. However, this classification does not include the concept of pancreatobiliary malunion and has caused some confusion, especially in regard to types Ic and IVA. Type Ic, showing fusiform dilatation, has a pancreatobiliary malunion and often extends continuously to the intrahepatic duct. Type IVA, with intrahepatic involvement, shows primary ductal stricture, especially around the hepatic hilum and umbilicus. The incidence of the stricture is considerably greater than was previously assumed, and upstream intrahepatic ducts often join the dilated duct, with distinct caliber change. Intrahepatic dilatation may develop primarily, due to the stricture, combined with weakness of the duct wall. This stricture can be corrected by portal dissection in the liver to obtain a large anastomosis. In patients with intrahepatic involvement, we should carefully find the stricture by suitable cholangiograms, or by intraoperative cholangioscopy. Detecting the ductal stricture is obviously important, rather than classifying the cyst as type Ic or IVA.

Adolescent↗

PubMed2003

Adopt a wait-and-see attitude for patent processus vaginalis in neonates.

PURPOSE: The purpose of this paper is to describe the ultrasonographic findings of the patent processus vaginalis (PPV) in neonates. METHODS: The patency of the processus vaginalis was examined by ultrasonography in 117 neonates. The ultrasonographic findings, with increment and decrement of the intraabdominal pressure, were categorized into 6 types as follows: type I, the intraabdominal organ is observed; type II, cystic PPV; type III, the PPV is widened with abdominal pressure increment, the length is > or =20 mm; type IV, the PPV contains moving fluid without PPV widening; type V, the PPV is widened with abdominal pressure increment, the length is less than 20 mm; type VI, others. The authors we regarded types I to IV as PPV with inguinal hernia. RESULTS: Twenty-two of 40 neonates with a birth weight under 2,500 g had PPV, including 8 with type I. Twenty of 37 premature neonates 22 to 37 gestational weeks had PPV, including 8 with type I. Eighty-one percent (13 of 16) of PPV in low-birth-weight neonates and 91% (10 of 11) in premature neonates closed spontaneously. The median ages at the time of spontaneous regression of PPV were 242 days in low birth weight neonates and 262 days in premature neonates. CONCLUSIONS: Most premature or low-birth-weight neonates with PPV regress spontaneously. The inguinal hernia in neonates (especially in premature or low-birth-weight neonates) should be observed until at least 9 months of age without attempting hernia repair.

Female↗

PubMed2003

Vertical ophthalmoplegia in a demented patient with striatopallidodentate calcification.

A case is presented here of a 73-year-old man who showed signs of dementia, supranuclear vertical ophthalmoplegia, pseudobulbar palsy, axial dystonia, mild rigidity, and parkinsonian gait. Computed tomography of the head revealed symmetrical calcification in the striatum, globus pallidus and dentate nucleus to an extraordinary degree. No metabolic conditions were observed that could explain the intracranial calcification. Oral administration of levodopa improved the patient's motor symptoms to some extent. Ophthalmoplegia, parkinsonism and dementia combined are typically seen in patients with progressive supranuclear palsy. However, the present case and a few others that have been reported would seem to indicate that these unique symptoms might also be found in patients with intracranial calcification.

Aged↗

PubMed2003

Ultrasonographic diagnosis for potential contralateral inguinal hernia in children.

PURPOSE: The authors describe the diagnostic approach and the reliability of the diagnosis using their ultrasonographic classification for potential contralateral inguinal hernia in children. METHODS: In children presenting with unilateral inguinal hernia, the contralateral processus vaginalis in the inguinal canal was examined preoperatively by ultrasonography with a 10-MHz transducer. The findings, with increment and decrement of the intraabdominal pressure, were categorized into 6 types as follows: type I, the intraabdominal organ is observed in the inguinal canal; type II, the patent processus vaginalis (PPV) is seen cystlike at the internal ring of the inguinal canal; type III, the PPV is widened with abdominal pressure increment (the length of the PPV is longer than 20 mm); type IV, the PPV contains moving fluid without PPV widening; type V, the PPV is widened with abdominal pressure increment (the length is shorter than 20 mm); type VI, others. Types I through IV were regarded as potential candidates for inguinal hernia. The diagnostic performance of the clinical examination, with or without the assistance of ultrasonography was analyzed retrospectively. RESULTS: The development rates of contralateral inguinal hernia following unilateral herniorrhaphy, before and after application of ultrasonographic diagnosis, were 10.2% (28 of 274 cases) and 1.5% (4 of 271 cases), respectively. The difference was statistically significant according to Fisher's Exact probability test. CONCLUSIONS: Contralateral herniorrhaphy should be performed on inguinal hernia candidates when ultrasonography shows types I through IV.

Adolescent↗

PubMed2003

[A case of Paenibacillus polymyxa bacteremia in a patient with cerebral infarction].

We report a case of Paenibacillus polymyxa bacteremia in a patient with cerebral infarction. The patient was a 93-year-old female who was admitted to our hospital. On the 4 day after admitted, she had a fever 38.2 degrees C. The result of the blood culture showed a gram positive spore bacillus in the blood culture bottle. As a result of performing 16SrDNA sequence analysis (500bp), it was a close relationship most by 99.26% P. polymlxa of coincidence was found. With a result using api 20E and api 50CH, this bacillus turned out to be P. polymyxa. The patient had a habit of weeding around her house daily. So we had to take her habit into consideration. We thought she could to get her hands injured. We assumed probably her habit might put her into high risk state of infection of this bacillus. We have supposed this bacillus might be infected with her through her blood.

Aged↗

PubMed2003

Steroid-responsive limbic encephalitis.

A 71-year-old man presented with gradually progressing cognitive decline following acute febrile exanthematous disorder. The MRI showed an abnormality in the bilateral limbic systems. An elevation of cerebrospinal fluid (CSF) protein with lymphocyte pleocytosis was noted. Immunoblot of the CSF revealed the presence of anti-white matter antibodies that mainly recognized astrocytes. Intravenous steroid followed by oral steroid reduced the symptoms to a remarkable degree. The patient has now been successfully sustained with steroid for more than two years. We considered that this case is classified as non-paraneoplastic limbic encephalitis, and acquired autoimmunity played a major role in the pathogenesis of this case.

Aged↗

PubMed2002

Methamphetamine increases the hippocampal alpha(2A)-adrenergic receptor and Galpha(o) in mice.

This study investigates the involvement of alpha(2)-adrenergic receptors (AR) in mouse brain induced by a low dose of methamphetamine (METH, 2 mg/kg). Immunohistochemical studies show that alpha(2A)-AR increased in the dentate gyrus area of the hippocampus 24 h after five repeated administrations of METH. The hippocampal alpha(2A)-AR proteins rose 3.2-fold when compared to the saline-administered mice. The other adrenergic receptor, alpha(1D)-AR, were not changed by the treatment. Moreover, alpha(o)-subunits of GTP-binding proteins (Galpha(o)), one of the downstream molecules of alpha(2A)-AR, was also increased by the treatment. These suggest that the repeated administration of low-doses of METH causes quantitative changes of the signaling of alpha(2A)-AR in the mouse hippocampus.

Adrenergic Uptake Inhibitors↗

PubMed2002

A new ruthenium complex with an electron-donating aminoindenyl ligand for fast metal-mediated living radical polymerizations.

A new ruthenium complex with an electron-donating aminoindenyl ligand induces a fast living radical polymerization of methyl methacrylate (MMA) in the presence of a chloride initiator to give polymers with controlled and variable molecular weights (Mn = 103-105) and very narrow molecular weight distributions (Mw/Mn < 1.1). The structure and high activity of the catalyst were analyzed by X-ray crystallography and cyclic voltammetry in comparison to those of a similar complex with an indenyl ligand.

Journal Article↗

PubMed2002

Characterization and purification of adenosine deaminase 1 from human and chicken liver.

Adenosine deaminase 1 (ADA1) was purified from human and chicken liver. The purified enzyme had a molecular weight of approximately 42,000 Da on SDS-PAGE. In humans, ADA1 was mainly purified concomitant with ADA-binding protein, dipeptidyl peptidase IV (DPP IV)/CD26; however, in chickens, only ADA1 without DPP IV was purified. Both human and chicken ADA1s showed similar properties on substrate specificities, sensitivities on inhibitors, and pH profile. However, they had different affinities with adenosine-Sepharose and IgG anti-ADA1-Sepharose. Human ADA1 was not adsorbed in adenosine-Sepharose column, but chicken ADA1 was adsorbed. As for IgG anti-ADA1-Sepharose column, the results were converse. Furthermore, human ADA1 could bind to DPP IV whereas chicken ADA1 could not.

Adenosine↗

PubMed2002

Stimulation of beta(3)-adrenoceptors causes phosphorylation of p38 mitogen-activated protein kinase via a stimulatory G protein-dependent pathway in 3T3-L1 adipocytes.

1. This study deals with phosphorylation and activation of p38 mitogen-activated protein kinase (MAPK) via beta(3)-adrenoceptor (AR) and the signal transduction pathway in 3T3-L1 adipocytes. 2. beta(3)-AR agonist BRL37344A (10 nM) caused phosphorylation and activation of p38 MAPK in 3T3-L1 adipocytes but not in fibroblasts. BRL37344A and also the other beta(3)-AR agonists, CGP12177A and SR58611A, caused p38 MAPK phosphorylation in dose-dependent manners. 3. The p38 MAPK phosphorylations by BRL37344A (10 nM), CGP12177A (100 nM), and SR58611A (10 nM) were not antagonized by beta(1)- and beta(2)-ARs antagonist 1-propranolol (100 nM) but blocked by beta(3)-AR antagonist SR59230A (10 microM), suggesting the phosphorylation was caused via beta(3)-AR. 4. The phosphorylations of p38 MAPK were completely abolished by treatment with cholera toxin (CTX) but not pertussis toxin (100 ng ml(-1), 24 h). Activation of Gs by CTX (100 ng ml(-1)) and adenylyl cyclase by forskolin mimicked p38 MAPK phosphorylation. 5. p38 MAPK phosphorylation by BRL37344A was reduced to almost 50% by cyclic AMP-dependent protein kinase (PKA) inhibitors such as H89 (10 microM) and PKI (10 microM). A src-family tyrosine kinases inhibitor PP2 (1 microM) also halved the p38 MAPK phosphorylation. Combined use of H89 (10 microM) and PP2 (10 microM) did not bring about further inhibition. 6. These results suggest that beta(3)-AR caused phosphorylation of p38 MAPK via Gs protein and partly through a pathway involving PKA and src-family kinase(s), although the contribution of the unidentified pathway remains to be clarified.

3T3 Cells↗

PubMed2002

Altered distribution of Sertoli cell vimentin and increased apoptosis in cryptorchid rats.

BACKGROUND/PURPOSE: Sertoli cell cytoskeletons play an important role in the process of spermatogenesis. The authors investigated the effects of cryptorchidism in immature rats on the distribution of Sertoli cell cytoskeletons and the incidence of testis germ cell apoptosis. METHODS: Immature 3-week-old rats were made cryptorchid unilaterally, and the distribution of Sertoli cell cytoskeletons by immunohistochemistry and germ cell apoptosis by TUNEL technique were evaluated at different day intervals. RESULTS: Immunohistochemical staining from control rats showed that the distribution of vimentin in Sertoli cells changes in developing rats. Basally, it is localized in the perinuclear region of the cell as well as in filament networks that project into the apical Sertoli cell cytoplasm in a "spokelike" pattern. In cryptorchidism, there was an intense vimentin immunoreactivity surrounding Sertoli cell nuclei along with the collapse of the apical extensions. This became significantly evident by 7 days. Microtubules occur in Sertoli cell cytoplasm apical to the nucleus. Cryptorchidism did not alter their distribution. Spontaneous apoptosis of germ cells occurs in the control testis, and a markedly increased incidence of apoptosis was observed in cryptorchidism by 7 days with decreased testis weight. CONCLUSIONS: Taken together, the authors propose that Sertoli cells are affected in cryptorchidism, and altered distribution of Sertoli cells vimentin filaments correlates with the increased germ cell apoptosis. Sertoli cell vimentin filaments are important for maintaining the structural integrity of the seminiferous epithelium.

Animals↗