Characterization of the myosin-binding subunit of smooth muscle myosin phosphatase

A myosin phosphatase was purified from chicken gizzard smooth muscle. The holoenzyme is a trimer and consists of 130,000-, 38,000-, and 20,000-Da subunits (in agreement with the results of Alessi et al.: Alessi, D., MacDougall, L. K., Sola, M. M., Ikebe, M., and Cohen, P. (1992) Eur. J. Biochem. 210, 1023-1035). The catalytic subunit, 38,000 Da, is the type 1 delta isoform, and its derived amino acid sequence is identical to the rat isoform. The larger subunit bound to myosin and also interacted with the catalytic subunit. cDNA clones encoding the large subunit were isolated from chicken gizzard cDNA libraries. Overlapping clones indicated the presence of two isoforms, and open reading frames of 2889 and 3012 bases were obtained. These encoded proteins of 963 and 1004 amino acids, with masses of 106,700 and 111,600 Da, respectively. The insert in the larger isoform is in the center of the molecule, at residues 512-552. The N-terminal third of the molecule is composed of eight repeat sequences, similar to the cdc10/SWI6 or ankyrin repeat. Myosin binding and binding to the catalytic subunit are properties of a 58,000-Da fragment that represents the N-terminal part of the molecule.

[Basic and clinical approaches for surgical treatment of intractable epilepsies]

Recent reports demonstrated that patients with medically intractable epilepsy were benefited with surgical treatments. Even in pediatric patients, early surgery is effective not only in seizure control but also in verbal, intelligent and social outcomes. In the present study, basic and clinical approaches in the treatment of intractable epilepsies were studied. In chronic cat model of intractable temporal lobe epilepsy induced by a microinjection of kainic acid, temporal cortical excision with amygdala focus resection or focus and hippocampal resections were examined by means of microsurgical technics. The cats with amygdala focus resection demonstrated spontaneous hippocampal seizures while cats with focus and hippocampal resection did not show seizures in the long time course after the surgery. In a cat model of cortical focal seizures, multiple subpial transection(MST) was examined. The cortical seizures, induced by a microinjection of kainic acid into unilateral sensori-motor cortex, were suppressed immediately after the MST. Postoperative course was uneventful and seizure was not recurred. However, pathological study demonstrated subpial scar formation at the site of MST in the sensori-motor cortex. In 38 patients with medically intractable epilepsies, surgical treatments were performed in the Department of Neurosurgery. Asahikawa Medical College. The site of the epileptogenic lesion was studied with Video-EEG longterm monitorings, Neuro-imagings with CT, MRI, interictal SPECT and/or ictal SPECT. At the surgery, intraoperative electrocorticograms(ECoGs) were monitored under light neuroleptanalgesia in order to localize epileptic focus. Seizure free rate with or without postoperative medication was 72%. Remarkable improvement was observed in 7 patients (18%), but, 4 patients (10%) did not show any improvement.

Gastric cancer surgery in patients aged at least 80 years old

Fifty-six patients with gastric cancer who were at least 80 years of age (range 80-88) (Group 1) were retrospectively investigated and compared with younger patients. The resectability rate was 80% (45/56) in Group 1, 88% (331/373) in Group 2 (patients aged between 70 and 79) and 91% (992/1,087) in Group 3 (patients aged under 70 years). Of the cases resected, 73% had advanced cancer in Group 1, 61% in Group 2 and 55% in Group 3. Total gastrectomy was performed in only 11% of the resected cases in Group 1, in 25% of those in Group 2 and in 33% in Group 3. Of these, combined resections were employed in none of the patients in Group 1, in 38% of those in Group 2 and in 47% of those in Group 3. Pathologically, 78% of Group 1 cancers were of the differentiated type, 68% of Group 2 and 49% of Group 3 cancers (Group 1: Group 3, p < 0.001). R3 gastrectomy was performed for advanced cancer in none of the patients in Group 1, in 21% in Group 2, and in 39% of those in Group 3. In resected early cancers, the lymph node metastasis (n) rate was 0% for Group 1, 10% for Group 2, and 9% for Group 3. In the advanced cases, n(+) was 67% for Group 1, 65% for Group 2, and 73% for Group 3. Postoperative complications occurred in 25% of Group 1 and in 12% of Group 2 patients. Anastomotic leakage occurred in 4% of Group 1 and in 5% of Group 2 patients. The 5-year-survival rate was 47% for all resected cases in Group 1, and 68% for Groups 2 and 3.(ABSTRACT TRUNCATED AT 250 WORDS)

Enhancement of fibroblast-dependent mast cell growth in mice by a conditioned medium of keratinocyte-derived squamous cell carcinoma cells

We investigated the increase in mast cell numbers at the sites of inoculation of keratinocyte-derived squamous cell carcinoma cell line (KCMH-1) cells in mice. A significant increase in the number of mast cells was observed at the sites of tumours developed at the sites of inoculation of the KCMH-1 cells. Enhancement of mast cell growth was observed by culturing bone marrow-derived mast cells (BMMC) on NIH/3T3 fibroblast monolayers in the presence of conditioned medium (TCM) obtained from KCMH-1. Activities of known factors for mast cell growth, such as interleukin-3 (IL-3), IL-4, IL-9, IL-10 and stem cell factor (SCF), were not detected in the TCM. Nerve growth factor (NGF) did not induce mast cell growth. Mast cell growth induced by the TCM needed 3T3 fibroblasts. These results suggest that KCMH-1 cells may produce a factor which induces mast cell growth with 3T3 fibroblasts, other than the already known mast cell growth factors. This may be the mechanism of mast cell accumulation at sites of tumours.

Prevalence of malaria and its relationship to anemia, blood glucose levels, and serum somatomedin c (IGF-1) levels in the Solomon Islands

As part of establishing effective methods for malaria control, the malaria-associated nutritional status was surveyed on Guadalcanal Island in the Solomon Islands in 1993. A total of 506 residents participated in this study. The slide positive rate for malaria was 54% (275/506) in all ages, with a high of 79% for children aged 4-6 years. Plasmodium falciparum was the most common species (52%), followed by P. vivax (29%). Splenomegaly in children from infants to age 15 was detected at the rate of 30% (104/343) by the palpation method. Body mass index was lower in Solomon Islanders than for the Japanese population up to 15 years old in both genders. Mean values for serum insulin-like growth factor-1 (IGF-1) were also lower in Solomon Islanders in children under 18 years old. The hemoglobin distribution curves were almost identical in the malaria-positive (P(+)) and -negative (P(-)) groups. The percentage of cases with less than 80 mg/dl of blood glucose and those with less than 50 ng/ml of IGF-1 were higher in the P(+) group than for the anti-malaria drug-untreated malaria-negative (P(-)D(-)) group. It is suggested that low blood glucose and low IGF-1 levels may have some relationship with the malaria infection.

Immunocytochemical localization of cathepsin L in the synovial lining cells of the rat temporomandibular joint

Localization of cathepsin L in the synovial lining cells of the normal rat temporomandibular joint was investigated by the avidin-biotin-peroxidase complex method for semithin (1 microns) cryosections and the colloidal gold-labelled IgG method for ultrathin sections of LR gold resin. At the light-microscopic level, type A (macrophage-like) and B (fibroblast-like) cells formed the synovial lining layer. Extensive immunoreactivity for cathepsin L was observed in many granules and vacuoles of type A cells, while in the type B cells, immunoreactivity was found in very few granules. In the sublining layer, macrophages and a few fibroblasts were positive for cathepsin L. By electron microscopy, at the peripheral cytoplasm of the type A cells close to the lateral intercellular spaces and joint cavity, numerous coated vesicles and vacuoles (probably early endosomes) indicating endocytotic function were found. Gold particles indicating cathepsin L were localized in the vesicles (primary lysosomes) in the perinuclear cytoplasm and in the larger amorphous vacuoles (1 microns dia) as phagolysosomes. In type B cells, gold particles were limited to the vesicles only (primary lysosomes). The cathepsin L-positive primary lysosomes were numerous in a few fibroblasts in the sublining layer. These results indicate that type A cells contain a large amount of cathepsin L, and suggest that these cells endocytose surplus substances such as collagen and proteoglycan fragments in normal rat TMJ, effecting their digestion and degradation by the action of this proteolytic cathepsin.

Hepatitis B virus with mutations in the core promoter for an e antigen-negative phenotype in carriers with antibody to e antigen

Hepatitis B virus (HBV) DNA clones were propagated from 57 carriers with antibody to hepatitis B e antigen (HBeAg) and sequenced within nucleotides (nt) 1685 to 1926 including the core promoter (nt 1742 to 1849) and the pre-C region (nt 1814 to 1900). Mutations in the core promoter or those in the pre-C region, or both, were detected in 328 (97.9%) of 335 clones from them. Five carriers were infected with HBV mutants with mutations in the core promoter alone, while 20 carriers were infected only with those in the pre-C region to abort the translation of HBeAg precursor; the remaining 32 carriers were infected with HBV mutants with mutations in both the core promoter and pre-C region. Some carriers infected with HBV with mutations in the core promoter exclusively had high HBV DNA titers, comparable with those in carriers infected with wild-type HBV, thereby indicating that such mutations would not affect the transcription of the HBV pregenome extensively. Two point mutations in the core promoter, from A to T at nt 1762 and from G to A at nt 1764, were most prevalent. The other mutations included a point mutation at either of the two nucleotides and their deletion. All of these mutations involved the TTAAA sequence (nt 1758 to 1762) at 28 bp upstream of the initiation site for shorter pre-C mRNAs (nt 1790 +/- 1). The ATAAATT sequence (nt 1789 to 1795) at 23 bp upstream of the initiation site for the pregenome RNA (nt 1818), however, remained intact in all 335 HBV DNA clones. HBV mutants with mutations in the core promoter, unaccompanied by pre-C mutations, prevailed and replaced wild-type HBV in two carriers as they seroconverted from HBeAg to the corresponding antibody. These results indicate that HBV mutants with an HBeAg- phenotype would be generated by mutations in the core promoter which might abort the transcription of pre-C mRNA but do not seriously affect that of pregenome RNA.

Urinary prolactin excretion in children with renal disease

The contribution of the kidney to the metabolism of prolactin has not yet been established. In the present study, urinary prolactin concentrations in 30 children with renal disease were measured by a newly devised, highly sensitive, time-resolved immunofluorometric assay. Median prolactin concentrations in the urine of children with renal disease, were 1.86 pmol/L-1 of urine (range: 0.17-546.31 pmol/L-1. By stepwise regression analysis, change in urinary prolactin levels as a function of the urinary beta 2-microglobulin concentrations was detected. These results indicate that prolactin urinary excretion in children with renal disease is dependent on the renal proximal tubular function.

[Perinatal outcome of pregnancies following therapy of infertility]

To evaluate the risks involved in post infertility pregnancy, the perinatal outcomes of 571 patients with infertility treatment in 9 institutions were analyzed by questionnaire retrospectively. The rate of multiple pregnancy and premature delivery was 14.5% (83/571) and 13.3% (76/571) respectively. Multiple pregnancies occurred in 33 cases with ovulation induction, 22 cases with artificial insemination by the husband (AIH) and 25 cases with in-vitro fertilization by embryo transfer (IVF). Premature deliveries occurred in 32 cases with ovulation induction. 26 cases with AIH and 14 cases with IVF. Three babies were dead and 4 babies were handicapped. In single post infertility pregnancy, the rate of premature birth was twice as high (9.0%) as in normal controls. The mortality rate was 0.45% (2/449), which was higher than that of controls. This suggests that post infertility pregnancies tend to result in multiple pregnancy and premature birth. In addition, in single post infertility pregnancies there was the possibility of poor perinatal outcome.

[Clinical significance of P-glycoprotein expression and multidrug resistance assessed by in vitro thymidine incorporation assay in patients with gastric carcinoma]

Drug resistance in chemotherapy is a significant problem in the treatment of gastric carcinomas as well as other malignant tumors. Multidrug resistant cells frequently overexpress the 170 kDa P-glycoprotein (P-gp). Twenty-four fresh tumor specimens of gastric carcinoma were assessed by flow cytometric detection of P-gp using monoclonal antibody C219. Eight patients were P-gp positive. Differentiated gastric carcinomas contained significantly higher concentrations of P-gp positive. Incidence of P-gp positive case was high in advanced stage. Sixteen cases received in vitro chemosensitivity test assessed by thymidine incorporation assay (TIA). Seven of 9 multidrug resistant cases by TIA were P-gp positive, and all of 7 non-multidrug resistance were negative. Expression of P-gp and multidrug resistance were closely correlated (p < 0.01). Also, in 89 patients with operable gastric carcinoma, the relationship between multidrug resistance by TIA and their clinicopathologic features as well as their survival lengths were examined. Thirty-one of 89 specimens from gastric carcinoma patients were multidrug resistant by TIA. Patients with multidrug resistant group had a significantly poorer cumulative survival rate than non-multidrug resistant cases (p < 0.01). The multivariated analyses showed that multidrug resistance analyzed is useful indicator for prognosis (p < 0.1). We suggest that multidrug resistance cases or P-gp-positive cases of gastric carcinoma are highly malignant, and these determinations are clinically useful.

Effect of ubenimex on the proliferation and differentiation of U937 human histiocytic lymphoma cells

We investigated the effect of ubenimex on the growth and differentiation of U937 cells, a histiocytic lymphoma cell line. Ubenimex is a dipeptide ((2S,3R)-3-amino-2-hydroxy-4-phenylbutyryl-L-leucine) and an inhibitor of aminopeptidase B produced by Streptomyces olivoreticuli. Ubenimex inhibited the proliferation of U937 cells in a dose-dependent manner. Ubenimex-treated U937 cells showed condensation of nuclear chromatin, increase of cytoplasmic vacuoles and more intense nonspecific esterase staining compared with untreated U937 cells. Expression of CD13 and CD68 detected by monoclonal antibodies My7 and EBM11, respectively, was enhanced by ubenimex, but the expression of CD4 detected by MT310 was significantly decreased. The effects of ubenimex on U937 cell growth inhibition and enhancement of monocytic cell surface marker expression on U937 cells were reversible when cultivated without ubenimex for more than 6 days. In addition, the bactericidal activity of U937 cells was increased by ubenimex treatment, and was further enhanced by treatment with macrophage colony-stimulating factor (M-CSF). Furthermore, ubenimex augmented the expression of M-CSF receptors by U937 cells and enhanced the tyrosine kinase activity of cellular pp60c-src. These findings indicated that ubenimex inhibited the proliferation of U937 cells and induced morphological, cytochemical and functional differentiation into monocyte/macrophages.

The role of the autonomic nervous system in the thermic effects of protein and carbohydrates in rats

To investigate the roles of the autonomic nervous system in the thermic effects of protein and carbohydrates in rats, we determined the urinary excretion of catecholamines and the resting oxygen consumption by means of HPLC-fluorometry and open-circuit respirometry, respectively. Protein administration significantly increased the urinary excretion of norepinephrine and epinephrine over those on water administration. The thermic effect of protein was 16.6% of the basal metabolic rate and was inhibited by phentolamine, prazosin, or atropine, but not by propranolol. These results suggest that the sympathetic nervous system via alpha 1-adrenoceptors and the parasympathetic nervous system are involved in the thermic effect of protein. The administration of carbohydrates such as glucose, sucrose, and fructose significantly enhanced the urinary excretion of norepinephrine, but only glucose administration increased the urinary excretion of epinephrine. The thermic effects of carbohydrates were 8-9% of the basal metabolic rate and were inhibited by propranolol, but not by phentolamine or atropine. These findings suggest that the sympathetic nervous system via beta-adrenoceptors, but not the parasympathetic nervous system, contributes to the thermic effect of carbohydrates. Thus, we conclude that the autonomic nervous system is involved in the thermic effects of protein and carbohydrates by different mechanisms.

[Suprasellar ectopic pituitary adenoma: report of a case]

An extremely rare case of an ectopic pituitary adenoma in the suprasellar region is reported. A 57-year-old man was referred to us in March, 1993, because of bitemporal hemianopsia. Magnetic resonance imaging (MRI) and computed tomography (CT) revealed a well-circumscribed enhancing mass in the suprasellar region. Sagittal tomography of the skull showed normal-sized sella turcica. Endocrinological tests were almost within normal range. The tumor was totally removed by combined right subfrontal and interhemispheric approach. At the time of the operation, we confirmed that the tumor did not continue to the pituitary gland and that the diaphragma sellae was intact. Histological diagnosis of the tumor specimen was pituitary adenoma. Post-operative MRI showed a normal pituitary gland, thus supporting the diagnosis of ectopic pituitary adenoma. To our knowledge, only ten cases of suprasellar ectopic pituitary adenoma have been reported, including our case. Pathogenesis of ectopic pituitary adenoma was briefly discussed.

Involvement of D1 dopamine receptor mechanism in ischemia-induced impairment of CA1 presynaptic fiber spikes in rat hippocampal slices

The effect of dopamine (DA) receptor agonists and antagonists on hypoxia/hypoglycemia (ischemia)-induced decrease in CA1 presynaptic fiber spikes elicited by the stimulation of Schaffer collateral were investigated using hippocampal slices. Treatment with D1 dopamine receptor antagonist, SCH23390 produced a concentration-dependent attenuation of the ischemia-induced decrease of presynaptic potentials. The magnitude of recovery of the CA1 presynaptic potential in SCH233390-treated slices at 10 and 100 microM was 28 and 54%, respectively. Whereas, treatment with D1 dopamine receptor agonist, SKF38393 exacerbated the ischemia-induced decrease in the CA1 presynaptic potential. The decrease of CA1 presynaptic potential by ischemia was affected by neither D2 dopamine receptor agonist, bromocriptin and quinpirole nor D2 dopamine receptor antagonist, sulpiride. The neuroprotective effect of SCH23390 was completely blocked by cotreatment with SKF38393. The present results demonstrated that the blockade of D1 dopamine receptor function played a neuroprotective role in ischemic damage, suggesting a facilitatory role of D1 dopamine receptor-operated function in ischemia-induced neuronal deficits.

Distinct relationship between HLA-DR genes and intractability of ulcerative colitis

OBJECTIVE

To explain the correlation between HLA class II genes and the intractability of ulcerative colitis (UC), DR genotyping and clinical analysis were performed for patients with UC.

METHODS

HLA-DRB types and HLA-DR2 subtypes of 45 patients with UC in our hospital were determined using molecular genotyping in combination with sequence-specific oligonucleotide hybridization by polymerase chain reactions. The extent of involvement, clinical course, and treatment were studied to evaluate the intractability of UC.

RESULTS

The gene frequency of DRB1*1502 in 18 patients with total colitis (0.444) was significantly higher than the group with left-sided colitis and proctitis (0.148; p < 0.05). In addition, DRw11 and DR2 increased significantly in the group including 18 cases with total colitis. In the 11 patients with total colectomy there were no cases with DRB1*1501, whereas 34 patients without operation included 12 genes of DRB1*1501 (p < 0.05). In addition, DRw11 increased significantly in the group with total colectomy compared to the group without operation (p < 0.05). When comparing between patients with and without intractability (defined based on the Japanese definition), DRB1*1502 and DRw11 were found more frequently in intractable UC patients (p < 0.01), whereas DRB1*1501 increased significantly in cases without intractability (p < 0.05).

CONCLUSIONS

DRB1*1502 or DRw11 have a probability of being closely related to the intractability of UC. In addition, patients with UC possessing DRB1*1501 have a lower probability of their cases leading to intractable UC. Thus, we believe there are unknown genes present that encode the intractability of UC.