Erythropoietin induces tyrosine phosphorylation and activation of phospholipase C-gamma 1 in a human erythropoietin-dependent cell line

Erythropoietin (Epo) is the major regulator of the proliferation and differentiation of erythroid precursors through interaction with its receptor (Epo-R). Although Epo-R lacks a tyrosine kinase consensus sequence within its intracellular domain, the addition of its ligand to Epo-responsive cells, UT-7/Epo, induces the rapid and transient tyrosine phosphorylation of 145-, 130-, 80-, and 40-kDa cellular proteins. Tyrosine phosphorylation of these proteins occurred dose- and time-dependently. We showed that the tyrosine phosphorylated 145- kDa protein is identical to phospholipase C-gamma 1 (PLC-gamma 1). Tyrosine phosphorylation of this protein is detectable within 30 s and almost reaches the maximum at 1 min. This can last up to 10 min and declines thereafter. Additionally, in Epo-stimulated cells, PLC-gamma 1 become physically associated with 80- and 40-kDa proteins which have been tyrosine-phosphorylated in response to Epo. The activity of PLC-gamma 1 was also investigated using inositol 1,4,5-trisphosphate (Ins-P3) as an indicator. We found that stimulation of UT-7/Epo cells with Epo induces a significant accumulation of Ins-P3. This effect is dose-dependent and occurs very rapidly. The production of Ins-P3 can explain the Epo-induced mobilization of calcium from intracellular stores in these cells. These results demonstrate that Epo induces tyrosine phosphorylation and activation of PLC-gamma 1 to produce Ins-P3 and then it mobilizes calcium from intracellular stores. This signal transduction pathway may play a role in regulating the proliferation of erythroid cells.

The identification of Escherichia coli ispB (cel) gene encoding the octaprenyl diphosphate synthase

The gene located upstream of the nlp gene at min 69 on the chromosome of Escherichia coli was cloned from the plasmid pLC7-42 constructed by Clarke and Carbon. The extract of the strain harboring the plasmid containing this gene showed increased activity of the prenyltransferase. The product of the enzyme reaction was analyzed by two systems of the thin-layer chromatography and shown to be the phosphate ester of all-E-octaprenol. These results suggested that the gene was the structural gene for the octaprenyl diphosphate synthase which supplied the precursor of the side chain of the isoprenoid quinones.

[Redo valve replacement for primary tissue failure of bioprosthetic heart valve]

We evaluated long-term results of valve replacement with bioprosthesis in 59 patients. Freedom from primary tissue failure and reoperation declined more than seven years after valve replacement. Seven patients underwent repeat operations because of primary tissue failure in our hospital. Their ages ranged from 32 to 54 years, two cases were male and five were female. At repeat operation, mechanical valve prosthesis were implanted to mitral position in all seven patients, tricuspid annuloplasty was added in five patients, and aortic valve replacement was added in one patients. The New York Heart Association (NYHA) functional classifications were grade II for 1 patient, III for 1, and IV for 5 preoperatively. Five patients had severe pulmonary hypertension preoperatively, and three of them were died after operation. The removed bioprostheses showed tears, perforations or calcifications of cusps and commissural detachments.

Therapeutic efficacy of the non-peptide AVP antagonist OPC-31260 in cirrhotic rats

The present study was undertaken to determine whether a non-peptide arginine vasopressin (AVP) antagonist [5-dimethylamino-1-(4-(2-methylbenzoylamino)benzoyl]-2,3,4,5-tetra hydro-1H- benzazepine] (OPC-31260) improves the impaired water excretion in rats with experimental liver cirrhosis. Male Wistar rats weighing 200 to 250 g were injected in an equal volume (4 ml/kg) of carbon tetrachloride and olive oil at an interval of seven days for three months, causing liver cirrhosis with ascites. Control rats were injected with only olive oil. Body weight (body wt) and hematocrit (Hct) were lower in the cirrhotic rats than the control rats (body wt 360.7 vs. 238.5 g, P < 0.01; Hct 46.3 vs. 39.2%, P < 0.01). A water loading test (30 ml/kg) was carried out and 20-minute urine collections were made for three hours. The percent of water load excreted was 62.5% in the cirrhotic rats, a value significantly less than that of 102.1% in the control rats. However, its percent increased to 215.1% after the oral administration of 5 mg/kg OPC-31260 (P < 0.01). Minimal urinary osmolality (UOsm) was 185.5 mOsm/kg H2O in the cirrhotic rats receiving the vehicle, a value greater than the control rats of 125.5 mOsm/kg H2O (P < 0.01). The oral administration of 5 mg/kg OPC-31260 reduced minimal UOsm to 85.2 mOsm/kg H2O in the cirrhotic rats (P < 0.01). Urinary excretion of sodium was lower in the cirrhotic rats than the control rats (87.1 vs. 312.4 microEq/3 hr, P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

[Effects of combination chemotherapy using 5-FU, leucovorin, and CDDP (FLP therapy) for noncurative resected or recurrent stomach cancer in outpatients]

We performed combination chemotherapy consisting of 5-FU, leucovorin, and CDDP (FLP therapy) against noncurative resected or recurrent stomach cancer in outpatients as of August 1991. Seventeen outpatients patients underwent FLP therapy until February 1993. Therapeutic responses, survival time after the operation or recurrence, rate at home, and the improvement of performance status (PS) were studied. The response rate was 54.5%, median survival time was 410 days, the rate at home was 75.5 +/- 14.7%, and the rate of improvement of PS was 82.4%. Toxicities were observed in 70.6%. Thrombocytopenia must be followed carefully, but it was encountered in only a few patients. FLP therapy for advanced or recurrent stomach cancer in outpatients was expected to improve the QOL.

Bovine leukemia virus induces CD5- B cell lymphoma in sheep despite temporarily increasing CD5+ B cells in asymptomatic stage

To investigate bovine leukemia virus (BLV)-induced leukemogenesis, we infected sheep with BLV and used flow-cytometric and immunohistological analysis to characterize the phenotypic alterations in lymphocytes from peripheral blood and lymph nodes taken from the animals with lymphoma at various stages. In sheep at the asymptomatic stage, depending on the extent of progression of the disease, the proportions of CD2(+)-, CD4(+)-, CD8(+)-, and gamma delta TCR(+)-T cells that coexpressed CD5 decreased, but CD5+ sIgM+ cells as well as CD5- sIgM+ cells increased for a period. The number of CD5+ B cells, however, rapidly decreased in the lymphoma stage. On the other hand, neoplastic lymphocytes appeared to be a monoclonal population derived from a single cell with surface phenotypes of sIgM+, B-cell-specific molecule B2+, major histocompatibility complex (MHC) class II+, OvCD5-, OvCD2-, OvCD4-, OvCD8-, gamma delta TCR-, which suggests that only CD5- B cells proliferate clonally when the disease proceeds to the lymphoma stage. Thus, rapid decrease of CD5+ B cells may be used as a marker of lymphoma stage. To identify the BLV provirus in the CD5- B and CD5+ B cells throughout the course of disease, each fraction of CD5- B and CD5+ B cell was sorted from the peripheral blood by flow cytometry and nested double polymerase chain reaction was performed. In BLV-infected but healthy sheep, BLV integrated both CD5- B and CD5+ B cells. In lymphoma, however, BLV provirus was detected only in CD5- B cells but not in CD5+ B cells. Therefore it appears that a disappearance of BLV-infected CD5+ cells is one of the critical events leading to CD5- B cell lymphoma in sheep. This is in contrast to the BLV-induced lymphoma in cattle which shows CD5+ phenotype.

Translocation (16;21)(p11;q22) in acute nonlymphocytic leukemia

A case of acute nonlymphocytic leukemia (ANLL) with a translocation (16;21)(p11;q22) is presented. Clinical features of ANLL with this chromosomal change are discussed.

Sodium ion mediated regulation of Na/K-ATPase gene expression in vascular smooth muscle cells

OBJECTIVE

Na/K-ATPase (Na,K pump) plays an important role in the regulation of intracellular ion composition. The purpose of this study is to determine whether Na+ regulates the levels of mRNA coding for Na/K-ATPase alpha and beta isoforms in cultured rat vascular smooth muscles cells.

METHODS

Na/K-ATPase alpha and beta isoform mRNA expression was evaluated by northern blot analysis. The alpha 1 subunit content was determined by ELISA. A luciferase reporter gene assay was performed to study whether the alpha 1 promoter might contain Na+ responsive elements.

RESULTS

Na/K-ATPase alpha 1 and beta 1 isoform mRNAs, but not alpha 2 and alpha 3 isoform mRNAs, were expressed in cultured rat vascular smooth muscle cells. Exposure of the cells to 10 microM veratridine, an Na+ channel activator, resulted in two- and threefold increases in alpha 1 and beta 1 mRNA accumulation, respectively, with a maximum at 60 min. The veratridine induced alpha 1 and beta 1 mRNA accumulation was still observed even in the absence of extracellular Ca2+. The increase in alpha 1 mRNA accumulation caused by 10 microM veratridine was associated with a significant increase in alpha 1 subunit protein accumulation. Transfection experiments with chimeric plasmids containing 5'-flanking sequences of alpha 1 isoform gene and luciferase reporter gene showed that 10 microM veratridine caused a threefold increase in luciferase activity.

CONCLUSIONS

These results suggest that Na+ stimulates the transcription of Na/K-ATPase alpha 1 and beta 1 isoform genes in vascular smooth muscle cells. The transfection study further supports the premise that Na+ responsive elements are located within the 5'-flanking sequences of alpha 1 isoform gene.

[Late phase II clinical study of irinotecan hydrochloride (CPT-11) in the treatment of malignant lymphoma and acute leukemia. The CPT-11 Research Group for Hematological Malignancies]

A nationwide multi-center cooperative phase II clinical study of irinotecan hydrochloride (CPT-11) was conducted to evaluate its efficacy in intractable malignant lymphoma and acute leukemia. In malignant lymphoma, one course of CPT-11 consisted of intravenous drip infusion at a dose of 40 mg/m2 once daily for 3 consecutive days, performed once a week. In acute leukemia, one course of CPT-11 consisted of intravenous drip infusion at a dose of 15 to 20 mg/m2 a day twice daily for 7 consecutive days (1 cycle), performed every 2 to 4 weeks. Among the 79 patients with malignant lymphoma and 50 patients with acute leukemia enrolled in the study, 66 and 41 patients, respectively, completed treatment. These patients had all undergone chemotherapy prior to treatment. Among the malignant lymphomas, the response rate in non-Hodgkin's lymphoma (NHL), including 9 CRs, was 42% (26/62, 95% CI: 30-54%); of these there was a response rate of 39% (5/13), including 1 CR, in adult T-cell leukemia (ATL) as well. In Hodgkin's disease (HD), on the other hand, there were no cases in which efficacy was demonstrated (0/4). The overall response rate in malignant lymphoma was 39% (26/66), and the response rate even among the recurrent intransigent cases was 42% (16/38). The 50% survival time (MST) in the 74 eligible cases of malignant lymphoma was 153 days. In acute leukemia, on the other hand, partial remission was observed in 2 of 17 cases (12%) of acute lymphocytic leukemia (ALL), but no cases of remission were observed in the 24 patients with acute myelogenous leukemia (AML). The overall remission rate in acute leukemia was 5% (2/41, 95% CI: 1-14%). The principal adverse effects were myelosuppression in malignant lymphoma and gastrointestinal symptoms, including diarrhea, nausea/vomiting, anorexia and abdominal pain, in both malignant lymphoma and acute leukemia, and there was little organ damage to the heart, liver or kidney. Myelosuppression and gastrointestinal adverse effects were severe in some of the patients, so caution is required. Based on the above findings, CPT-11 appears to be efficacious in the treatment of non-Hodgkin's lymphoma.

[Relationship of AIDS-related knowledge with attitudes of nursing students toward HIV-infected persons]

The relationship of AIDS-related knowledge of nursing students to their attitude toward HIV-infected persons was examined, and the effect of a 90-minute educational seminar on their knowledge and attitudes was evaluated. A survey of 72 nursing students was performed in Kochi prefecture in October, 1992 using a questionnaire. Eighty-six mothers whose children received medical examinations at the health center of the surveyed area during the same period functioned as the control group. Although the students had more knowledge about HIV/AIDS, their attitudes toward HIV-infected persons were no more positive than those of the control group. However the higher their level of knowledge was, the more positive their attitudes toward people with AIDS were. Two items of knowledge: symptoms of infection and safety in sharing utensils appeared to be related to positive attitudes. Those students who thought that "the number of HIV-infected persons will rapidly increase" tended to respond that "they are worried about getting AIDS in the future"; "they will not change their attitudes to their HIV-infected friends"; and "the persons who got AIDS through coagulation factor products should be supported." The results also show that a seminar about HIV/AIDS that provides information in a short period of time is effective in reducing prejudice and improving attitudes toward HIV-infected persons.

Genotypical classification of neutrophil Fc gamma receptor III by polymerase chain reaction-single-strand conformation polymorphism

We classified the genotype of neutrophil Fc gamma receptor III (FcRIII) (CD16) with a new method. Genomic DNA from mononuclear cells of 39 unrelated healthy donors (13 NA1/NA1, 13 NA2/NA2, and 13 NA1/NA2 typed serologically) were subjected to polymerase chain reaction (PCR) to amplify the polymorphic third exon of the FcRIII genes. The PCR products were heat denatured, electrophoresed, and visualized by silver staining. Allelic differences were detected by distinctive electrophoretic patterns of each single strand, depending on their sequence specific conformations (single-strand conformation polymorphism [SSCP]). The genotypes of neutrophil FcRIII determined by this method were consistent with the phenotypes of NA antigens determined by serologic examinations. These results indicate that the PCR-SSCP system is a very useful tool for genotyping of the neutrophil FcRIII.

Effects of endothelin-1 on intraocular pressure and aqueous humor dynamics in the rabbit eye

The effects of endothelin-1 (ET-1) on intraocular pressure (IOP) and aqueous humor dynamics were studied in the rabbit eye. The intravitreal injection of 10(-5) M ET-1 (20 microliters) produced a biphasic IOP response consisting of an initial rise of 1 to 2 hours in duration, and a subsequent prolonged reduction lasting for more than 96 hours. Aqueous humor dynamics were determined 24 hours after the 10(-5) M ET-1 injection. Aqueous humor formation, measured fluorophotometrically, was decreased by 58%. Total outflow facility increased by 94%, according to measurement by two-level constant pressure perfusion. The change of uveoscleral outflow determined by fluorescein-dextran perfusion was not significant. The decrease in aqueous flow and the increase in total facility accounted for most of the IOP reduction after the ET-1 injection. Endothelin, which is endogenously present in the eye, may play a role in the regulation of intraocular pressure.

Low density lipoprotein enhances the cellular action of arginine vasopressin in rat glomerular mesangial cells in culture

The present study was undertaken to determine whether low density lipoprotein (LDL) modulates the cellular action of arginine vasopressin (AVP) in rat glomerular mesangial cells in culture. AVP increased cellular free calcium ([Ca2+]i) in a dose-dependent manner. When cells were preincubated for 24 h with 10 microgram/ml LDL, the 1 x 10(-7) M AVP-mobilized [Ca2+]i was 874 nM, a value significantly greater than that of 375 nM in the intact cells. AVP caused a biphasic change in cellular pH (pHi), namely, an early acidification followed by a sustained alkalinization, and the change in pHi produced by AVP was also enhanced by LDL. AVP stimulated a 2.2-fold increase in [3H]thymidine incorporation, an effect significantly greater in the presence of 10 micrograms/ml LDL. Furthermore, 1 x 10(-7) M AVP significantly activated mitogen-activated protein kinase from 14.0 to 24.5 pmol/mg protein. Such an activation was significantly enhanced by the LDL pretreatment. Both [3H]thymide incorporation and mitogen-activated protein kinase were not altered by 10 micrograms/ml LDL. [3H]AVP receptor binding was not affected by the LDL pretreatment. 1 x 10(-7) M AVP increased inositol trisphosphate production by 1.9-fold, an effect significantly greater in the presence of LDL. These results indicate that LDL enhances the cellular action of AVP and the AVP-stimulated cellular proliferation in glomerular mesangial cells. A site of action of LDL is the hydrolysis of phosphatidylinositol.

[Clinico-pathological study of carried-over patents with Henoch-Schönlein nephritis]

Fifty-two (49.5%) of 105 children with Henoch-Schönlein purpura developed nephritis. Eleven (21.1%) of 52 nephritic patients were carried over beyond childhood, while 21 (40.4%) cases had normalized urinalyses in childhood. The carried-over patients had a higher incidence of severe proteinuria and tubular atrophy compared to those of patients with normalized urinalyses (p < 0.05). These results suggest that patients with severe proteinuria and tubular atrophy tend to have persistent urinary abnormalities beyond childhood.

Clinical experience of lower urinary tract reconstruction using a urethral Kock pouch

The operative procedure used in the present series involved a nerve-sparing radical cystectomy, with anastomosis of the urethra using a pouch made of detubularized ileum. The 36 patients who underwent this operation were all male with an average age of 58. No deaths resulted from the operation. As far as late complications were concerned, malfunction of the antireflux nipple valve was noted in 1 patient and stenosis occurred between the urethra and pouch in 2. One patient was found to have multiple stones in the pouch and reservoir decompensation was recognized in 2. Thus, the late complication rate was 17%. There were no cases of total incontinence, but nocturnal incontinence appeared in 11 out of 31 (35%). A total of 20 out of 25 patients (80%) recovered their erectile function during the postoperative follow-up period and the disease-free survival rate at 5 years was 78%. Therefore, the urethral Kock pouch combined with nerve-sparing cystectomy has proved to be a useful procedure as far as the quality of life is concerned.

Pseudohypoparathyroidism-associated spinal stenosis

STUDY DESIGN

Pseudohypoparathyroidism associated with disorders of the spine is rarely reported. In this report, the authors present a case of pseudohypoparathyroidism in a 41-year-old man who had narrow spinal canal and multiple disc herniation in the cervical spine.

SUMMARY OF BACKGROUND DATA

The patient had progressive spastic tetraplegia due to cervical cord compression caused by multiple disc herniations at the C3-C4, C4-5, and C5-C6 levels in the developmentally narrow spinal canal. Based on the features of Albright's osteodystrophy, serum laboratory results, and an Ellsworth-Howard test, the diagnosis of pseudohypoparathyroidism, type I was confirmed.

METHODS

The patient underwent expansive laminoplasty at C3 through C6 levels.

RESULTS

His symptoms have gradually improved during the 1-year and 6-month periods after the surgery.

CONCLUSIONS

A case of pseudohypoparathyroidism-associated spinal stenosis was reported.

Development of an instrument to measure postmortem lividity and its preliminary application to estimate the time since death

A degree of postmortem lividity was related to a subcutaneous hemoglobin concentration, which can be measured by using light absorption. On the basis of this theory, the authors have developed an instrument utilizing a light to measure the degree of postmortem lividity. By using 42 corpses whose postmortem intervals were known, the authors examined the relationship between the actual postmortem intervals and the measurements, and found that there was significant correlation between them.

Distinct inhibition by non-peptide and peptide arginine vasopressin antagonists of vasopressin-induced activation of mitogen-activated protein kinase in cultured rat vascular smooth muscle cells

The preincubation of vascular smooth muscle cells (VSMC) with a non-peptide arginine vasopressin (AVP) antagonist (OPC-21268) (0.5 mM) for 10 min completely inhibited the 1 microM AVP-induced activation of mitogen-activated protein (MAP) kinase but did not affect the angiotensin II-, protein kinase C activator- or ionomycin-stimulated MAP kinase. Similar results were obtained with the simultaneous administration of AVP and OPC-21268. This inhibitory effect of OPC-21268 completely disappeared after washing the cells pretreated with OPC-21268. In contrast, the preincubation of VSMC with a peptide AVP antagonist, d(CH2)5Tyr(Me)AVP (1 microM), for 10 min completely blocked the 1 microM AVP-activated MAP kinase but the simultaneous administration of d(CH2)5Tyr(Me)AVP with AVP could inhibit that only by 40%. However, the washing procedure did not affect the inhibitory effect of d(CH2)5Tyr(Me)AVP. These results indicate that OPC-21268 is a specific AVP antagonist to inhibit the AVP-induced activation of MAP kinase. The antagonistic effect of OPC-21268 is also suggested to be relatively weak but prompt as compared to that of a peptide AVP antagonist d(CH2)5Tyr(Me)AVP.

[Prospective study on the influence of social activity on development of dementia in the neurologically normal elderly]

We investigated the rate of development of dementia in 84 neurologically normal elderly subjects living in an old-age home (30 subjects, mean 77.2 years) or their own home 954, 73.7) prospectively. We examined cerebral blood flow (CBF), Hasegawa's scale (HS) and Kohs' block design test 6 to 9 years before this study (1991). HS and Kohs' IQ were significantly lower in the old-age home group than that in their own home group at that time. However, there were no demented subjects. Mortality was 21%, and we confirmed 9 dementia and 6 stroke cases during the period of observation. Twenty-seven percent of the old-age home group showed dementia in 1991. This rate was significantly higher than that for the elderly living in their own home (6.7%). Occurrence of stroke was also significantly higher in the former group than in the latter group. The subjects who developed stroke during observation showed a high incidence of dementia. Mean CBF measured on the first examination was significantly lower in dementia cases with stroke than in dementia cases without it. We performed MRI in 4 demented cases in 1991 (Fig. 1). Two cases showed no significant lesions and the other cases showed cerebral infarction which could cause dementia. These results indicate that life style and social environment may have significant effect on aging of the brain and on development of dementia in the elderly.

Scaphoid megalourethra with multiple urogenital anomalies

A male infant with scaphoid megalourethra, which is a rare congenital anomaly, is presented. At birth he exhibited a grossly swollen, malformed penis and cryptorchidism. The corpus spongiosum was not palpable. The infant had congenital renal failure. Retrograde urethrography revealed a crescent-shaped dilatation of the anterior urethra, and the diagnosis of scaphoid megalourethra was made. Subsequent uroradiological examinations showed that there were also severe urogenital anomalies, i.e. renal hypoplasia-dysplasia, hydronephrosis, hydroureter and vesicoureteral reflux. This disorder is frequently associated with other urogenital anomalies. Therefore, once the diagnosis is reached, a careful investigation for other associated abnormalities should be undertaken.

CA125-producing adenocarcinoma of the seminal vesicle

A case of primary seminal vesicle carcinoma is reported. The tumor was a CA125-producing adenocarcinoma consisting of fine papillary-tubular, intricate branching or anastomosing glandular structures and was composed of small cuboidal, but occasionally hobnailed, cells with mostly clear, but occasionally granular, cytoplasm. Some tumor cells showed evidence of secretion of seromucinous materials into the interpapillary and cystic space. Immunohistochemically, almost half of the tumor cells expressed a positive reaction with anti-CA125, a common serological marker for ovarian epithelial carcinomas; however, no tumor cells expressed any other serological tumor markers such as carcinoembryonic antigen, alpha-fetoprotein, human chorionic gonadotropin, prostatic specific acid phosphatase, or prostatic specific antigen. The patient showed a high level of serological CA125, which fluctuated parallel with the growth, removal and recurrence of the tumor. The morphological and immunohistochemical findings suggested a close relationship between the present tumor and clear cell carcinoma of the ovary, which is thought to be of a Müllerian-Wolfian duct origin.

Phenotype analysis of lymphocytes present in different stages of neoplasia induced by bovine leukemia virus

Distribution of subpopulations of lymphocytes in the lymph nodes and tumor tissues from cattle with enzootic bovine leukosis (EBL) was examined by immunohistology using a panel of monoclonal antibodies against leukocyte differentiation molecules of bovine leukocytes and tumor-associated antigen (TAA) of EBL. As disease progressed in the lymph nodes, TAA positive cells increased in number and were strongly positive. The number of B-B2, IgM positive cells were reduced in frequency in the follicle and areas of neoplastic cell-proliferation. Alpha beta and gamma delta T cells positive for WC1 (workshop cluster designation) were reduced in frequency due to infiltration and proliferation of neoplastic cells. In tumor tissues which were thought to consist with monoclonal population of cells carrying BLV provirus, strongly TAA-positive cells were present throughout the section. Most of the neoplastic cells from five cattle with EBL appeared to be divided into four types, CD2-, CD4-, CD8-, WC1-, B2+ or B2-, IgM+ or IgM-, MHC II+ and strong TAA+. WC1+ cells played no apparent role in the development of lymphosarcoma of EBL. WC1+ cells were not observed in tumor tissues. However, the possibility of effect of T cell for tumor immunity was suggested, since TH/l and Tc/s cells were scattered in the tumor tissues.