Significance of urinary type IV collagen in patients with diabetic nephropathy using a highly sensitive one-step sandwich enzyme immunoassay

Urinary concentrations of type IV collagen in patients with diabetic nephropathy were measured by a highly sensitive, one-step sandwich enzyme immunoassay. Samples from 298 patients with noninsulin-dependent diabetes mellitus (NIDDM) and 80 healthy controls were examined. In diabetic patients with macroalbuminuria or renal insufficiency, the concentrations of urinary type IV collagen were significantly higher than those of diabetic patients with normoalbuminuria or healthy controls (P < 0.001). Urinary type IV collagen concentration in diabetic patients with microalbuminuria was significantly higher than that in diabetic patients with normoalbuminuria or that in healthy controls (P < 0.001). In contrast, there were no significant changes in the concentration of serum type IV collagen between microalbuminuric patients and normoalbuminuric patients. The area under the receiver operating characteristic (ROC) curve for the urinary type IV collagen concentration was equivalent to that of urinary albumin. It was concluded that urinary type IV collagen concentration determined using this method might be a useful marker for the early detection of diabetic nephropathy.

A long-term follow-up study on risk factors for hepatocellular carcinoma among Japanese patients with liver cirrhosis

To identify virological parameters (serostatus of hepatitis B surface antigen [HBsAg] and antibodies to hepatitis C virus [anti-HCV], HCV genotypes and HCV-RNA titer) and other clinico-biological and lifestyle variables that may influence or predict the development of hepatocellular carcinoma (HCC) in cirrhosis, we followed 100 cirrhotic patients without HCC, who visited Kyushu University Hospital between 1985 and 1987, until the end of 1995 (follow-up rate: 98%; average follow-up period: 5.3 years). After elimination of 4 patients who developed HCC or were censored within the initial 6 months, 37 (39%) out of 96 patients developed HCC during follow-up. As compared with HBsAg(+) patients, anti-HCV(+) HBsAg(-) patients demonstrated significantly elevated HCC risk (adjusted hazard ratio [HR] = 5.85, 95% confidence interval [CI] 1.65-20.67). Genotype 1 HCV infection was not associated with increased risk compared with genotype 2 (HR = 0.64, 95% CI 0.21-1.99). For genotype 1 HCV infection, patients with HCV-RNA levels < 1 Meq/ml tended to present lower risk than patients with > or = 1 Meq/ml (P = 0.03). Male sex, advanced Child's class, lower serum albumin, and higher serum aminotransferase and alpha-fetoprotein were also found to be strong predictors. Overall, drinking and smoking habits were not associated with significantly elevated risk. Among virological parameters, anti-HCV positivity and, possibly high HCV-RNA titer, were predictive of HCC occurrence in cirrhosis in our clinical setting.

Prevalence and renal prognosis of diagnosed autosomal dominant polycystic kidney disease in Japan

The prevalence and renal prognosis of diagnosed autosomal dominant polycystic kidney disease (ADPKD) in Japan were estimated. Hospital-based nationwide surveys were conducted in 1995. The number of ADPKD patients who visited hospitals but were not on chronic dialysis was estimated to be 10,000 (95% confidence interval: 8, 200-11,900) and that of ADPKD patients on dialysis was 4,590, yielding a prevalence of ADPKD of 117 per million population at the end of 1994 (95% confidence interval: 102-132). The prevalence increased with age and reached a peak value of 261 per million population at the age group of 55-59 years. The rate of end-stage renal disease among living patients was calculated based on the assumption that the prevalence of ADPKD in the population under the age of 55 years was 261 per million population. The rate of end-stage renal disease increased with the progression of the patients' age, reaching 49% at the age of 65-69 years and declining thereafter.

CONCLUSION

The hospital-based prevalence of ADPKD is lower than the autopsy-based prevalence, suggesting that a fairly large number of these patients do not receive medical care in their lifetime. The probability of end-stage renal disease is at most 50% among ADPKD patients who visit a hospital.

Plasma viscosity regulates capillary perfusion during extreme hemodilution in hamster skinfold model

Effect of increasing blood viscosity during extreme hemodilution on capillary perfusion and tissue oxygenation was investigated in the awake hamster skinfold model. Two isovolemic hemodilution steps were performed with 6% Dextran 70 [molecular weight (MW) = 70,000] until systemic hematocrit (Hct) was reduced by 65%. A third step reduced Hct by 75% and was performed with the same solution [low viscosity (LV)] or a high-molecular-weight 6% Dextran 500 solution [MW = 500, 000, high viscosity (HV)]. Final plasma viscosities were 1.4 and 2.2 cP (baseline of 1.2 cP). Hct was reduced to 11.2 +/- 1.1% from 46.2 +/- 1.5% for LV and to 11.9 +/- 0.7% from 47.3 +/- 2.1% for HV. HV produced a greater mean arterial blood pressure than LV. Functional capillary density (FCD) was substantially higher after HV (85 +/- 12%) vs. LV (38 +/- 30%) vs. baseline (100%). PO2 levels measured with Pd-porphyrin phosphorescence microscopy were not statistically changed from baseline until after the third hemodilution step. Wall shear rate (WSR) decreased in arterioles and venules after LV and only in arterioles after HV. Wall shear stress (WSR x plasma viscosity) was substantially higher after HV vs. LV. Increased mean arterial pressure and shear stress-dependent release of endothelium-derived relaxing factor are possible mechanisms that improved arteriolar and venular blood flow and FCD after HV vs. LV exchange protocols.

The significance of the expression of tumor suppressor gene DCC in human gliomas

Deleted in colorectal carcinoma (DCC) gene has been as a candidate of tumor suppressor genes, has been identified recently and is thought to relate to the metastatic potential in some cancers. We examined the gene in 60 human gliomas (26 glioblastomas multiforme (GBMs), 16 anaplastic astrocytomas (AAs), 6 low grade astrocytomas (LGAs) of WHO Grade II, and 11 recurrent gliomas) and A172 human GBM cell line by reverse transcription polymerase chain reaction (RT-PCR). Twenty (77%) GBMs, 11 (69%) AAs, and 1 (17%) LGA revealed the reduced or absent DCC expression. Reduced DCC expression was also shown in 10 (91%) recurrent gliomas. Furthermore, in 5 cases with both primary and recurrent GBM, the DCC expressions of all recurrent tumors were lower than those of primary tumors. No significant correlation between DCC expression and Mib-1 labeling index was confirmed. The survival rate of patients without reduced DCC expression was significantly superior to that of patients with reduced DCC expression in overall malignant astrocytic tumors. In GBM and AA separately, DCC expression also tended to correlate with patient's prognosis. These results suggest that reduced DCC expression is an important marker in tumor malignancy and recurrence in astrocytic tumors and that may be a useful prognostic factor in patients with malignant astrocytic tumors.

Structures of membrane proteins determined at atomic resolution

Following determination of the first crystal structure of the reaction center of Rhodopseudomonas viridis, a membrane protein, by X-ray crystal structure analysis at 3.0 A resolution, 18 X-ray crystal structures and two electron crystal structures of membrane proteins have been obtained at higher than 3.5 A resolution. Besides these integral membrane protein structures, three crystal structures of water-soluble proteins, which can enter membranes, have been determined by X-ray crystallography at high resolution. The structural features of membrane proteins have been summarized by inspecting these crystal structures. The polypeptide chain crosses the membrane in a helical conformation or a beta-strand. The central +10 A region of the transmembrane alpha-helix is dominated by hydrophobic residues. On both sides of the central region are concentrated polar aromatic residues. Charged residues are dominant around +15 A to +20 A. All the transmembrane beta-structures are found in pore-forming proteins. The central region of the transmembrane beta-structure is amphipathic with hydrophobic residues on the membrane exposed side. The distribution of amino acid residues on the membrane exposed surface of the transmembrane beta-structure is similar to that of the transmembrane alpha-helix. alpha-Helices anchoring the membrane surface region are amphipathic with hydrophobic residues inside and hydrophilic residues outside.

Study of immunoelectron microscopic localization of cathepsin K in osteoclasts and other bone cells in the mouse femur

The localization of cathepsin K protein in mouse osteoclasts was examined by immunolight and immunoelectron microscopy using the avidin-biotin-peroxidase complex method with anti-cathepsin K (mouse) antibody. With light microscopy, a strong immunoreaction for cathepsin K was found extracellularly along the bone and cartilage resorption lacunae and detected intracellularly in vesicles, granules, and vacuoles throughout the cytoplasm of multinuclear osteoclasts and chondroclasts attached to the surface of the bone or cartilage. Mononuclear cells, probably preosteoclasts, some distance from the bone also contained a few cathepsin K-positive vesicles and granules. Cathepsin K was sometimes found in the cisternal spaces of the rough endoplasmic reticulum and vesicles of the Golgi apparatus with electron microscopy of the basolateral region of the osteoclasts. Cathepsin K-positive vesicles and granules as lysosomal compartments were present in various stages of fusion with vacuoles as endosomal compartments that contained fragmented cathepsin K-negative fibril-like structures. Some of the vacuoles (endolysosomes), which seemed to be formed by this process of fusion, contained cathepsin K-positive vesicles and fibril-like structures that did not show the regular cross striation of type I collagen fibrils. In the apical region of the osteoclasts, cathepsin K-positive vesicles and pits had already fused with or were in the process of fusing with the ampullar extracellular spaces. There were large deposits of cathepsin K on fragmented fibril-like structures without regular cross striation in the extracellular spaces, as well as on and between the cytoplasmic processes of the ruffled border. There were also extensive deposits of cathepsin K on the type I collagen fibrils with cross striation in the bone resorption lacunae. Osteoblasts and osteocytes were negative for cathepsin K. In the immunocytochemical controls, no immunoreaction was found in the osteoclasts or preosteoclasts, or on the collagen fibrils in the resorption lacunae. The results indicate that cathepsin K is produced in mature osteoclasts attached to the bone and secreted into the bone resorption lacunae. The findings suggest that cathepsin K participates in the extracellular degradation of collagen fibrils in the resorption lacunae and in the subsequent degradation of the fragmented fibrils in the endolysosomes. It is also suggested that cathepsin K degrades the organic cartilage matrix.

Phosphorothioate hammerhead ribozymes targeting a conserved sequence in the V3 loop region inhibit HIV-1 entry

Seven different phosphorothioate DNA-RNA chimeric hammerhead ribozymes (RzV3-nT, n = 1-7) targeted against the V3 loop region of HIV-1 were synthesized. Two of these, RzV3-1T and RzV3-3T, efficiently cleaved transcribed envelope RNA of HXB2 in vitro. The target sequence of RzV3-1T belongs to a conserved region and is completely identical in the HIV-1 HXB2, NL432, and ADA strains. Furthermore, RzV3-1T cleaved the envelope RNA of HIV-1 SF162 with a single base substitution in the distal site. U87 cells expressing CD4 and coreceptors were used as target cells for infections with the SF162 and NL432 strains. Replication of both the NL432 and SF162 strains in RzV3-1T-treated cells was significantly lower than that in control cultures. Envelope gene product formation was measured quantitatively with a single-cycle infection assay using pseudovirus generated from cotransfection with one vector containing a luciferase reporter gene and one vector containing the envelope gene of HXB2, SF162, or ADA. Production of pseudovirus in RzV3-1T-treated cells led to a marked (93% or 87%) inhibition of envelope-mediated entry of resultant HXB2-derived or ADA-derived pseudotype virions, respectively, and a moderate (44%) inhibition was seen for SF162-derived pseudotype virions. Thus, an efficient, stable ribozyme against a functionally important region of HIV-1 was identified by evaluating its activities in vitro and in vivo. This ribozyme may be useful for control of HIV-1 infection.

Cyclic GMP-dependent cytoprotection against ethanol-induced damage in rabbit isolated gastric parietal cells

Prostaglandin E2 stimulates a nitric oxide/cyclic GMP (NO/cGMP) pathway which activates basolateral Cl- channels in rabbit gastric parietal cells. We examined whether the NO/cGMP pathway protects parietal cells from ethanol (EtOH)-induced cytotoxicity, using a parietal cell-rich suspension purified from rabbit gastric mucosa. Cytotoxicity was assayed by measuring the release of a fluorescent dye from the cells. N2,O2-dibutyryl guanosine 3',5'-cyclic monophosphate (DBcGMP) showed a concentration-dependent protective effect against EtOH-induced cytotoxicity. The half-maximal effect of DBcGMP was observed at 24 microM. DBcGMP in a concentration-dependent manner opened the basolateral Cl- channels of parietal cells, the EC50 value being 44 microM. The EtOH-induced cytotoxicity decreased as the Cl- concentration of medium decreased. A 30-s treatment with 5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB), an inhibitor of the Cl- channel, had a cytotoxic effect which was not prevented by pre-incubation with DBcGMP. The cytotoxic effects of EtOH and NPPB were additive and the NPPB effects did not depend on the medium Cl- concentration. The present study showed that cGMP protects the gastric parietal cell from EtOH-induced cytotoxicity, and this cytoprotection is related to basolateral Cl- channel activity in the plasma membrane via an unknown mechanism(s).

Inhibition of integrin signaling with Arg-Gly-Asp motifs in rat hepatic stellate cells

BACKGROUND/AIMS

Activation of hepatic stellate cells plays a key role in liver fibrogenesis. Disruption of normal hepatic stellate cell-matrix interactions may contribute to this process. However, little is known about the molecular events leading from integrin-extracellular matrix interaction to hepatic stellate cell function. Therefore, we investigated the role of integrin signaling in tyrosine phosphorylation of focal adhesion kinase and cytoskeletal assembly in rat hepatic stellate cells using soluble Arg-Gly-Asp containing peptides.

METHODS

Hepatic stellate cells were isolated from normal rat livers. Integrin alpha5beta1 expression in hepatic stellate cells was analyzed by immunoprecipitation and immunocytochemistry. The cytoskeletal assembly and tyrosine phosphorylation of focal adhesion kinase were determined by immunocytochemistry and immunoblotting. We also analyzed the effect of Arg-Gly-Asp containing peptides on the expression of smooth muscle alpha actin by immunocytochemistry and immunoblotting.

RESULTS

We identified integrin alpha5beta1 in rat hepatic stellate cells. Stress fiber formation and cell shape were different when hepatic stellate cells were plated on various extracellular matrix components. Treatment of hepatic stellate cells with soluble Arg-Gly-Asp peptides diminished the adhesion-induced tyrosine phosphorylation of focal adhesion kinase and inhibited the formation of stress fibers. The peptides also reduced the expression of smooth muscle alpha actin.

CONCLUSIONS

Our results demonstrate that adhesion to extracellular matrix induces tyrosine phosphorylation of focal adhesion kinase and promotes actin stress fiber formation and focal adhesion assembly in rat hepatic stellate cells, and that these events are disturbed by soluble Arg-Gly-Asp peptides.

Two-component response regulators from Arabidopsis thaliana contain a putative DNA-binding motif

An expression sequence tag database of higher plants was screened by in silico profile analysis for response regulators of the two-component regulatory system. Two closely related clones (ARR1 and ARR2), corresponding to one of the extracted candidates, were isolated from Arabidopsis thaliana. The two genes were comparably expressed in all tissues, and at higher levels in the roots. The amino-terminal half of their translation products was highly conserved. This is where a phosphate receiver domain with the landmark aspartate residue and a putative DNA-binding domain were located. Their carboxyl-terminal halves, although less similar to each other, included glutamine-rich and proline-rich regions characteristic of the transcriptional activation domain of eukaryotes. This architecture resembles that of typical bacterial response regulators serving as transcription factors.

Progressive multifocal leukoencephalopathy in a patient with acquired immunodeficiency syndrome (AIDS) manifesting Gerstmann's syndrome

We reported a case of acquired immunodeficiency syndrome (AIDS) via multiple blood transfusions, who manifested progressive multifocal leukoencephalopathy (PML) about 18 months after the development of AIDS. PML initiated with right hemiparesis, dysphasia, and Gerstmann's syndrome and resulted in death within 2 months after the onset. Neuroimaging examinations revealed white matter lesions mainly in the left posterior parietal lobe. The cortical gray matter also showed abnormal signal intensity. Peripheral CD4+ lymphocyte count was 81/microl. Routine cerebrospinal fluid (CSF) examinations were negative. CSF antibodies against herpes simplex virus, varicella-zoster virus, cytomegalovirus, Epstein-Barr virus as well as serum antibody against toxoplasma gondii were negative. Though autopsy or biopsy of the brain was not performed, JC virus genomes were detected in the CSF sample by a polymerase chain reaction, and their sequencing showed unique alterations of the regulatory regions, characteristic to PML-type JC virus.

Characterization of muscarinic receptors in rat bronchial smooth muscle in vitro

This study was undertaken to assess the important muscarinic receptor subtype in acetylcholine (ACh)-induced rat bronchial smooth muscle contraction. Ring smooth muscle strips of the left main bronchus were used. Isometrical contraction was measured in response to ACh in cumulative concentrations (10(-7)-10(-3) M) with and without preincubations with the muscarinic receptor antagonists, pirenzepine (an M1 antagonist), methoctramine (an M2 antagonist), and 4-diphenylacetoxy N-methylpiperidine (4-DAMP; an M1/M3 antagonist). Preincubation with these antagonists resulted in concentration-dependent rightward shifts of the concentration-response curves to ACh. pA2 values (means+/-sem) were 8.80+/-0.10 for 4-DAMP, 7.03+/-0.06 for pirenzepine and 5.91+/-0.36 for methoctramine, indicating that the most important muscarinic receptor mediating ACh-induced contraction of rat bronchial smooth muscle is of the M3 type.

Protein kinase C-mediated up-regulation of Na+/Ca2+-exchanger in rat hepatocytes determined by a new Na+/Ca2+-exchanger inhibitor, KB-R7943

The regulatory mechanism of the plasma membrane Na+/Ca2+-exchanger in isolated rat hepatocytes was studied using microspectrofluorometry and 45Ca2+ uptake methods. Exposure of single hepatocytes to low-Na+ solutions induced an increase in the intracellular Ca2+ concentration ([Ca2+]i) which depended on the presence of extracellular Ca2+. 2-[2-[4-(4-nitrobenzyloxy)phenyl]ethyl]isothiourea methanesulfonate (KB-R7943), a novel selective inhibitor of Na+/Ca2+-exchangers, inhibited the initial rate of [Ca2+]i increase induced by exposure to the low-Na+ solution (IC50 = 2 microM). KB-R7943 also reduced the initial rate of 45Ca2+ uptake (IC50 = 4 microM). The increase in [Ca2+]i induced by exposure to the low-Na+ solution was inhibited by pre-incubation with 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H-7, 50 microM), but not with N-[2-(methylamino)ethyl]-5-isoquinolinesulfonamide (H-8, 60 microM) or a tyrosine kinase inhibitor, genistein (100 microM). Furthermore, taurocholate and phorbol-12,13-dibutyrate, both of which activate protein kinase C, promoted the increase in [Ca2+]i. These [Ca2+]i increases were sensitive to KB-R7943. Our results indicate that the Na+/Ca2+-exchanger is up-regulated via protein kinase C. The activity of Na+/Ca2+-exchangers is not evident under normal physiological conditions, suggesting that the exchanger may be activated under pathophysiological conditions.

Generation of protein carbonyls by glycoxidation and lipoxidation reactions with autoxidation products of ascorbic acid and polyunsaturated fatty acids

Accumulation of carbonyl derivatives of proteins (protein carbonyl) is taken as a biomarker of oxidative protein damage in aging and in various diseases. We detected protein carbonyls in situ in human diabetic arteriosclerotic tissues and characterized the formation of protein carbonyls. Protein carbonyls were identified in the thickened intima of arterial walls and co-localized with protein adducts formed by carbonyl amine chemistry between protein and carbonyl compounds derived from autoxidation of carbohydrates, lipids, and ascorbate, i.e. advanced glycation end products or glycoxidation products, such as carboxymethyllysine (CML) and pentosidine, and lipoxidation products, such as malondialdehyde (MDA) and 4-hydroxy-nonenal (HNE). In vitro incubation of proteins with ascorbic acid accelerated the production of protein carbonyls as well as CML and pentosidine, and incubation with arachidonate accelerated the production of protein carbonyls as well as CML, MDA, and HNE. By contrast, incubation of proteins with glucose resulted in the production of CML and pentosidine, but not protein carbonyls. Schiff base inhibitors, (+/-)-2-isopropylidenehydrazono-4-oxo-thiazolidin-5-ylace tanilide and aminoguanidine, inhibited the production of protein carbonyls after incubation with ascorbate and arachidonate. The present study suggests that ascorbate and polyunsaturated fatty acids, but not glucose, represent potential sources of protein carbonyls, and that both the glycoxidation and lipoxidation reactions contribute to protein carbonyl formation in aging and various diseases.

Different response to inflammation of the multiple mRNAs of rat N-acetylglucosaminyltransferase I with variable 5'-untranslated sequences

We found that there are at least five subclasses of N-acetylglucosaminyltransferase I (GnT-I; EC 2.4.1.101) mRNA with different 5'-untranslated regions in rat brain. These five subclasses were also expressed in many tissues with distinct tissue-specific patterns. Moreover, they were regulated differently in response to acute-phase inflammation. The expression of the most abundant subclass of GnT-I mRNA in rat liver decreased 2.5-fold in response to inflammation, concomitantly with a significant decrease in the total amount of GnT-I mRNA. In contrast, one of the minor subclasses of GnT-I mRNA was induced 10-fold by inflammation.

[Clinical utility of the free prostate specific antigen (PSA), alpha 1-antichymotrypsin-complexed PSA, and free/total PSA ratio using the specific and sensitive enzyme-linked immunosorbent assay "E-plate EIKEN PSA"]

We studied the clinical significance of serum prostate specific antigen (PSA) ratio: free-PSA/total-PSA and free-PSA/complex-PSA to discriminate between prostate cancer (PC) and prostate benign disease (non-PCa) by using total-PSA, alpha 1-antichymotrypsin complexed (complex)-PSA and free-PSA enzyme-linked immunosorbent assay (ELISA) kits newly developed at EIKEN Chemical Co, Ltd. Fre-PSA and complex-PSA ELISA kits demonstrated high sensitivity and specificity. Total-PSA ELISA kit also demonstrated equimolarity for free-PSA and complex-PSA. On the total-PSA range of 4-10 ng/ml, free-PSA/total-PSA% (f/t%) and free-PSA/complex-PSA% (f/c%) were very useful to discriminate between PCa and non-PCa by receiver operating characteristic curve analysis as well as PSA density (PSA-D) but not free-PSA level. F/t% and f/c% were even useful to discriminate early stage PCa (i.e. A1 or B0) from non-PCa by the Mann-Whitney U-test.

Effect of an alpha-glucosidase inhibitor (voglibose), in combination with sulphonylureas, on glycaemic control in type 2 diabetes patients

A multicentre study was conducted to evaluate the effect of the alpha-glucosidase inhibitor, voglibose, on glycaemic control in 113 patients with type 2 diabetes whose blood glucose control was poor on treatment with a sulphonylurea drug. The patients were treated for 24 weeks with 0.6 mg voglibose, given orally three times daily, before a meal, together with their usual sulphonylurea drug treatment. In the 86 patients who completed the study, fasting plasma glucose, 2-h post-prandial plasma glucose and haemoglobin showed statistically significant decreases in FPG, 2h-PPG and HbA1c compared with the baseline (P < 0.05) at almost all time-points during treatment. No serious adverse reactions were reported and there were no significant changes in mean body weights. Plasma glucose control was considered to be improved in 65% of patients; there were no adverse events in 92.9% of patients. The results suggest that the combined use of this alpha-glucosidase inhibitor and sulphonylurea drugs may be effective in controlling plasma glucose in patients with type 2 diabetes and that this combination might delay the onset of vascular complications in these patients.

Angiotensin I-converting enzyme gene polymorphism in intracranial saccular aneurysm individuals

A polymorphism in the angiotensin I-converting enzyme (ACE) gene has been associated with cerebrovascular diseases as a new potent risk factor. The purpose of this study was to investigate an association of the gene polymorphism with intracranial saccural aneurysmal patients. The study population consisted of 83 aneurysmal patients (age range 41-85 years) (the AN group) and 104 matched control subjects (age range 30-81 years) (the Control group). For detection of the ACE gene polymorphism, the standard PCR method was performed by using genomic DNA isolated from peripheral blood leukocytes. The PCR products were a 490-bp in the presence of the insertion (I) and a 190-bp fragment in the absence of the insertion (D). The ACE gene polymorphism was classified into three genotypes: I/I genotype (a 490-bp band); D/D genotype (a 190-bp band); or I/D genotype (both a 490-bp and a 190-bp band). The number of subjects with I/I, I/D, and D/D genotypes was 38, 40, and 5 in the AN group and 43, 45, and 16 in the Control group, respectively. The frequency of the D/D genotype in the AN group was significantly lower (5/83 = 0.06) than that in the Control group (16/104 = 0.15) (chi 2 = 4.06; p = 0.044). There was no significant difference between the genotype sof hypertensive patients and normotensive patients in the AN group. Thus, this present study suggests that genetic heterogeneity of the ACE gene may be correlated with the etiology of intracranial aneurysms.

[Detection of coronary artery disease by adenosine triphosphate stress echocardiography: comparison with adenosine triphosphate stress thallium myocardial scintigraphy and coronary angiography]

The clinical feasibility and usefulness of adenosine triphosphate-2Na (ATP) stress echocardiography for the detection of coronary artery disease (CAD) were assessed. Two-dimensional echocardiography and thallium-201 single photon emission computed tomography (SPECT) during ATP infusion were performed simultaneously in 58 consecutive patients (41 men and 17 women; mean age 66 +/- 12 years) with suspected CAD. ATP was infused intravenously at 0.16 mg/kg/min for 5 min and thallium was injected at 4 min. All patients underwent coronary angiography within 2 weeks of ATP echocardiography and ATP SPECT. An ischemic response during ATP infusion was detected by echocardiography as the development or worsening of a wall motion abnormality compared with the baseline and by SPECT as a perfusion defect that filled totally or partially during redistribution. Significant coronary artery stenosis was defined as > or = 75% diameter stenosis in a major epicardial vessel. The severity of the stenosis was classified as follows: Group A, lesions with significant coronary artery stenosis (> or = 75%, < 90%); Group B, lesions with severe coronary artery stenosis (> or = 90%) without collateral circulation; Group C, lesions with severe coronary artery stenosis (> or = 90%) with collateral circulation. Significant CAD was present in 43 of 58 patients. The overall sensitivity, specificity and accuracy of ATP echocardiography for detecting significant CAD were 70%, 100% and 78%, respectively, and those of ATP SPECT were 98%, 87% and 95%, respectively. In patients without previous myocardial infarction, the sensitivity of ATP echocardiography was 67%. The sensitivity of ATP echocardiography and ATP SPECT for detecting myocardial ischemia were 59% and 95% in patients with 1-vessel disease, 75% and 100% in those with 2-vessel disease, and 88% and 100% in those with 3-vessel disease, respectively. The induction of wall motion abnormality by ATP echocardiography was highly concordant with ATP SPECT imaging in patients with multivessel disease. Although the sensitivity of ATP echocardiography improved in patients with multivessel disease more than in those with single-vessel disease, detection of all diseased vessels was achieved in only 10% of patients with multivessel disease. The sensitivity of ATP echocardiography and ATP SPECT for detecting myocardial ischemia in individual vessels were: right coronary artery, 58% and 74%; left anterior descending artery, 59% and 97%; left circumflex artery, 27% and 68%. ATP-induced transient perfusion defects were associated with transient wall motion abnormality in only 57% of segments. The sensitivity of ATP echocardiography and ATP SPECT for detecting myocardial ischemia in patients with severe coronary stenosis were: Group A, 32% and 66%; Group B, 60% and 93%; Group C, 80% and 95%. The sensitivity of ATP echocardiography was significantly higher in the lesions with collateral circulation than in those without collateral circulation. ATP stress echocardiography is useful for detecting myocardial ischemia in patients with multivessel disease and in patients with severe coronary artery stenosis (> or = 90%). In particular, transient wall motion abnormality tends to be detected in the segments perfused by collateral circulation.

Expression profile of prostate-specific antigen messenger RNA assessed by in situ hybridization is a novel prognostic marker for patients with untreated prostate cancer

The present study was undertaken to define the relationship between histological grade (Gleason grade) and prostate-specific antigen (PSA) mRNA expression and to evaluate the level of PSA mRNA expression as a possible prognostic marker for untreated prostate cancers. The primary grade areas of 104 prostatic biopsy specimens were analyzed for the expression of PSA mRNA and its protein by nonradioactive in situ hybridization and immunohistochemistry, respectively. A multivariate survival analysis was performed to examine the correlation between PSA mRNA expression and several clinicopathological parameters, e.g., the immunostaining level of PSA protein in biopsy specimens. The percentage of specimens positive for PSA mRNA increased significantly with advanced histological grade. Image analysis of the signal intensity for PSA mRNA showed a significant correlation between the signal intensity in both primary and secondary grade areas of each specimen and the histological grade (P < 0.0001). Only 26.0% of specimens positive for PSA protein were also positive for PSA mRNA (and vice versa, 6.7%). Other tumors were either positive for both (66.3%) or negative for both (1.0%). When the Cox's proportional hazards regression model was used to analyze cancer-specific survival, untreated patients with higher levels of PSA mRNA expression in the higher grade (representing higher grade of either primary or secondary grade) area of tumors were at high risk for cancer-related death (P = 0.017). Furthermore, in cancer-specific survival curves based on PSA mRNA expression status, patients with high levels of PSA mRNA expression in the higher grade area of tumors had a significantly poorer prognosis (P = 0.001), compared with those with tumors expressing low levels of PSA mRNA. Our results suggested that analysis of PSA mRNA expression in specific areas in biopsy specimens of patients with untreated prostate cancer may provide a good assessment of prognosis of prostate cancers.

A mesangium-predominant gene, megsin, is a new serpin upregulated in IgA nephropathy

Mesangial cells play an important role in maintaining a structure and function of the glomerulus and in the pathogenesis of glomerular diseases. To identify a specific gene expressed in human mesangial cells, we used a rapid large-scale DNA sequencing and computerized data processing to compare the transcripts in cultured human mesangial cells with various different cells and organs. Using this novel approach, we discovered a new mesangium-predominant gene termed "megsin." We obtained a full-length cDNA clone of megsin, which coded for a novel 380-amino acid protein. Amino acid homology search revealed that megsin belonged to the serpin (serine protease inhibitor) superfamily. The amino acid sequences in the reactive loop site of megsin showed characteristic features of functional serpins. Northern blot and reverse-transcribed PCR analyses of various tissues and cells demonstrated that megsin was predominantly expressed in human mesangial cells. In situ hybridization studies showed the megsin expression in the mesangium of normal glomeruli, while it increased in the expanded mesangium of glomeruli from patients with IgA nephropathy with the degree of mesangial proliferation. Here we report a new human mesangium-predominant gene that may function as an inhibitory serpin in normal and abnormal biological processes of glomerulus.

Molecular cloning and cell-cycle-dependent expression of a novel NIMA (never-in-mitosis in Aspergillus nidulans)-related protein kinase (TpNrk) in Tetrahymena cells

With the intention of investigating the signal-transduction pathway that mediates the cold-stress response in Tetrahymena, we isolated a gene that encodes a novel protein kinase of 561 amino acids, termed Tetrahymena pyriformis NIMA (never-in-mitosis in Aspergillus nidulans)-related protein kinase (TpNrk), by differential display from Tetrahymena cells exposed to temperature shift-down. TpNrk possesses an N-terminal protein kinase domain that is highly homologous with other NIMA-related protein kinases (Neks) involved in the control of the cell cycle. The TpNrk protein is 42% identical in its catalytic domain with human Nek2, 41% identical with mouse Nek1 and 37% with A. nidulans NIMA. In addition, TpNrk and these NIMA-related kinases have long, basic C-terminal extensions and are therefore similar in overall structure. In order to further explore the function of the TpNrk gene and the association of the cold stress with the cell cycle of Tetrahymena, changes of TpNrk mRNA were determined during the course of the synchronous cell division induced by the intermittent heat treatment. The level of TpNrk transcription increased immediately after the end of the heat treatment, with a peak at 30 min, and declined thereafter reaching the minimum level when nearly 80% of the cells synchronously entered cell division (75 min after the end of heat treatment). The accumulation of TpNrk mRNA starting from 0 min to 30 min after the end of the heat treatment was assumed to be a prerequisite for the start of synchronous cell division. These results suggest that TpNrk may have a role in the cell cycle of Tetrahymena, and that mRNA expression, at least, is under tight cell-cycle control.

Seroprevalence of Taenia solium cysticercosis in pigs in a rural community of Honduras

Several retrospective studies have shown that human Taenia solium cysticercosis is endemic in Honduras, but very few reports of porcine cysticercosis in rural communities have been published. To determine the local prevalence of this disease in pigs, a serological survey has been undertaken in a rural community, Salamá, in the Department of Olancho in central Honduras. Eighty-five families raising pigs in the community were randomly selected and sera were obtained from pigs older than one month of age. The sera were examined by the enzyme-linked immunoelectrotransfer blot assay (EITB). Of 192 porcine sera, 27.1% (52) were positive by the EITB. Seropositivity did not correlate with age and sex by statistical analysis. With respect to the number and the frequency of recognition of the seven diagnostic glycoprotein bands in the EITB, 67.3% of the positive serum specimens recognized only one band and 80.8% of them recognized GP42-39. Since recognition of GP42-39 has been reported as a characteristic of late infection, these results suggest that most of the seropositive pigs were in the late stage of infection (more than 5-8 weeks postinfection). It seems that pigs in this community may be infected with this parasite soon after the birth and be in a hyperendemic steady state. In view of a high prevalence of antibodies to T. solium in pigs or characteristics of the antigen detected by the EITB, the infection pressure of T. solium appears to be very high in this community. This is probably the case in most of the communities in Honduras.