Membranoproliferative glomerulonephritis associated with hepatitis C virus infection responsive to interferon-alpha

A 42-year-old man with hepatitis C virus infection, cryoglobulinemia, hypocomplementemia, and nephrotic syndrome is reported. The kidney biopsy showed membranoproliferative glomerulonephritis. The patient was treated with interferon-alpha for 2 months. After the treatment, serum hepatitis C virus RNA became negative and nephrotic syndrome remitted. Repeat biopsy of the kidney revealed an improvement in renal histology. This case confirms an association between hepatitis C virus infection and membranoproliferative glomerulonephritis and the usefulness of interferon-alpha for treatment.

Cloning and sequencing of a 36-kb region of the Bacillus subtilis genome between the gnt and iol operons

Within the framework of an international project for the sequencing of the entire Bacillus subtilis genome, a 36-kb chromosome segment, which covers the region between the gnt and iol operons, has been cloned and sequenced. This region (36447 bp) contains 33 complete open reading frames (ORFs; genes) including the four gnt genes and one partial gene. A homology search for the products of the 33 complete ORFs revealed significant homology to known proteins in 16 of them such as tetracycline resistance protein (Clostridium perfringens), asparagine synthetase (Arabidopsis thaliana), aldehyde dehydrogenase (Pseudomonas oleovorans), 2,5-dichloro-2,5-cyclohexadiene-1, 4-diol dehydrogenase (P. paucimobilis), heat shock protein HtpG (Escherichia coli), galactose-proton symporter (E. coli), auxin-induced protein (common tobacco), glucitol operon repressor (E. coli) and methylmalonate-semialdehyde dehydrogenase (P. aeruginosa). Unlike the regions we sequenced so far, this region contained two short sequence multiplications: one was a tandem sequence duplication (409 and 410 bp), and the other a triplication consisting of two highly conserved 118-bp tandem sequences preceded by a less conserved similar sequence (129 bp). The reasons for the presence of these sequence multiplications in the gnt to iol region were deduced.

[Auditory brainstem responses by click stimuli via an earphone--comparison with a headphone]

To evaluate the variations of auditory brainstem responses (ABR) recorded using different receivers, the recordings of ABR were performed in 10 neurologically and audiometrically normal subjects who were all females (20-21 years of age) using a headphone (DR-513B-6) and an earphone (YE-102J). The peak latencies, the interpeak latencies, and the amplitudes of wave I, III, and V at each ABRs were compared. Unilateral auditory stimuli consisted of alternate click with 0.1 msec duration at intensity of 110 dB SPL and at rate of 13 Hz was given to the subjects who lay in the supine position at awake state. The active electrode was placed on the vertex (Cz) and the reference electrode on the left or right mastoid. The responses recorded from Cz to the ipsilateral mastoid were amplified by a factor of 10 microV/DIV with a bandpass filter of 10 Hz-3 KHz, a total of 1000 responses was averaged. It was recognized that the output intensity via the earphone was lower than the headphone, the difference was approximately 5 dB. Furthermore, the frequency response of the earphone was worse than the headphone at high frequency area (over 3.5 KHz). There were characteristic differences between ABRs recorded using the headphone and the earphone. The prolongation of the latency and the decrease of the amplitude were identified at only wave I of ABRs recorded using the earphone. However, no significant changes were founded at another components.(ABSTRACT TRUNCATED AT 250 WORDS)

Morphogenesis of esophageal carcinoma induced by N-methyl-N'-nitro-N-nitrosoguanidine in the house musk shrew, Suncus murinus (Insectivora)

The histological changes occurring in the esophageal mucosa of shrews (Suncus murinus) after N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) treatment were investigated sequentially. Six-week-old female shrews were given a 50 micrograms/ml MNNG solution as drinking water for 30 weeks, and 5 selected at random were killed at 10 and 20 weeks of age, and thereafter at 5-week intervals until 45 weeks of age. Controls were killed at 45 weeks of age. The MNNG-induced esophageal lesion in shrews began from basal cell hyperplasia at 20 weeks of age, followed by dysplasia occurring at 25 weeks of age, then progressed toward intraepithelial carcinoma to invasive squamous cell carcinoma at 35 weeks of age. Apparent sequential dysplasia-carcinoma transition was seen. Papillomas were seen from 25 weeks of age but there was no evidence of papilloma-carcinoma sequence. Five MNNG-untreated shrews killed at the end of the experiment were free of esophageal tumors.

A naturally occurring mutation at the second base of codon asparagine 43 in the proposed N-linked glycosylation site of human lipoprotein lipase: in vivo evidence that asparagine 43 is essential for catalysis and secretion

The patient was a 20-year-old male. His fasting plasma triglyceride and cholesterol levels were 1258 mg/dl and 138 mg/dl, respectively. The lipoprotein lipase (LPL) activity and mass from postheparin plasma of the patient were 0.00 mumol/ml/h (normal range: 5.51 +/- 1.12) and 23 ng/ml (normal range: 220 +/- 42), respectively. DNA sequence analysis of the LPL gene from the patient revealed a homozygous nucleotide change: a A-->G transition at nucleotide position 383, resulting in an amino acid substitution of Ser for Asn43, which is believed to be an N-linked glycosylation site of the LPL mature protein. Expression studies of this mutant LPL cDNA produced an inactive LPL protein which was not secreted into the media.

Immunohistochemical characteristics of breast-carcinoma in patients receiving neuroleptic therapy

The immunohistochemical characteristics of 17 cases of breast carcinoma in patients treated with neuroleptics (prolactin-releasing drug) are reported. Sixteen of the patients were female and one was male. Sixteen tumors in thirteen patients were invasive ductal carcinoma, two tumors in two patients were lipid-secreting carcinoma, one tumor was apocrine carcinoma, and two tumors in one patient were mucinous carcinoma. Elevated serum prolactin (Prl) levels (>15.0 ng/ml) were seen in all 7 patients whose preoperative serum prolactin levels had been determined. Immunohistochemical staining showed that 71% (15/21) of the carcinomas reacted positively for prolactin receptor (PrlR), while immunoreactive Prl was totally negative. Fourteen tumors were estrogen receptor (ER)-positive (67%; 14/21), and 12 were progesterone receptor (PgR)-positive (57%; 12/21). These results suggest that Prl secreted from the pituitary gland may interact with PrlR present on the cancer cells, but there was no evidence of de novo synthesis or uptake of Prl by cancer cells. ER and PgR status showed no characteristic immunoreactivity compared with unselected breast carcinoma patients not related to neuroleptic use.

GDP/GTP exchange reaction-stimulating activity of Rabphilin-3A for Rab3A small GTP-binding protein

Rabphilin-3A is a putative target protein for Rab3A, a small GTP-binding protein particularly implicated in neurotransmitter release. Rabphilin-3A interacts more preferentially with GTP-Rab3A than with GDP-Rab3A. Moreover, Rabphilin-3A shows a weak activity to stimulate the GTPase activity of Rab3A and a strong activity to inhibit the Rab3A GTPase-activating protein (GAP)-stimulated GTPase activity of Rab3A. Here, we show that Rabphilin-3A has another activity to stimulate the GDP/GTP exchange reaction of Rab3A. Rabphilin-3A may keep Rab3A continuously in the GTP-bound form by converting again GDP-Rab3A, which may be converted from GTP-Rab3A by Rab3A GAP, to GTP-Rab3A, until the function of Rab3A is accomplished.

[Detection of intratumoral DNA heterogeneity in primary lung cancer using a multiple sampling method]

The nuclear DNA contents of 18 freshly resected specimens of primary lung cancer tissue were determined by flow cytometry with a multiple sampling method. A DNA aneuploidy pattern was observed in all cases. In three cases, a diploid DNA pattern was observed along with abnormal DNA stem lines. Twelve cases (66%) had two or more abnormal DNA stem lines, and were classified as DNA multiploidy. The frequencies of DNA aneuploidy and DNA multiploidy were higher than in previously reported studies. Intratumoral DNA heterogeneity was observed in 10 cases (55%). Three of these were a mixture of DNA diploidy and DNA aneuploidy, and the other seven were a mixture of DNA aneuploidy and DNA multiploidy. If multiple sampling had not been performed in these cases, their ploidy patterns would have been misinterpreted. We conclude that multiple sampling is important in determining the precise DNA ploidy patterns of primary lung cancers.

Adsorption of human recombinant erythropoietin on dialysis membranes in vitro

The adsorptive characteristics of 5 dialysis membranes for recombinant human erythropoietin (EPO) were studied in vitro in a closed circuit system. For 120 min, EPO added with bovine serum was significantly adsorbed by polymethylmethacrylate (PMMA) and polyacrylonitrile (PAN) membranes but not by Cuprophan, ethylene vinyl alcohol (EVAL), or polysulfone (PS) membranes. In addition the EPO adsorptive rate, as well as that of beta 2-microglobulin (beta 2-MG), was greater with a PMMA membrane than with a PAN membrane. EPO was not detected in the ultrafiltrate at 15 min with 5 membranes. These results indicate that EPO was eliminated by membrane adsorption only with some dialysis membranes.

Possible function and some properties of the CcpA protein of Bacillus subtilis

The ccpA mutations alsA1 (alsA1 is allelic to ccpA) and ccpA::Tn917 completely abolished catabolite repression of gluconate kinase and sorbitol dehydrogenase synthesis in Bacillus subtilis, whereas they only partially affected the catabolite repression of inositol dehydrogenase, histidase and xylose isomerase synthesis. The alsA1 mutation also partially affected catabolite repression of sporulation. Analysis of revertants from the alsA1 mutant by direct sequencing indicated that this mutation comprises a base substitution of guanine at nucleotide -14 to adenine within the Shine-Dalgarno sequence of the ccpA gene (ccpA translation starts at nucleotide +1). A 1.37 kb EcoRI fragment carrying the ccpA gene was cloned into Escherichia coli plasmid pUC19 and B. subtilis plasmid pUB110, resulting in plasmids pCCPA19 and pCCPA110, respectively. The ccpA gene carried in pCCPA110 complemented the alsA1 mutation. Western blotting revealed that the level of the CcpA protein in B. subtilis cells, which seemed to be constitutively synthesized, was approximately 10 times lower for the alsA1 mutant than for the wild-type. The CcpA protein synthesized by either E. coli cells bearing pCCPA19 or B. subtilis cells bearing pCCPA110 was purified to over 90% homogeneity; the latter cells were grown in the presence of glucose. The molecular mass of the protein purified from E. coli was 74 kDa, suggesting that this protein exists as a dimer because its subunit molecular mass was 38 kDa as determined by SDS-PAGE. Gel retardation analysis indicated that the purified CcpA protein in both cases did not bind to the cis sequence for catabolite repression of the gnt operon, but it bound non-specifically to DNA.

Basic fibroblast growth factor-binding domain of heparan sulfate in the human glomerulosclerosis and renal tubulointerstitial fibrosis

BACKGROUND

The saccharide side chains of heparan sulfate (HS) proteoglycans show enormous complexity. These polysaccharides can interact specifically with cytokines such as basic fibroblast growth factor (bFGF). The understanding of HS expression in glomerulosclerosis and interstitial fibrosis, which is still rudimentary, could provide some insight about the role of bFGF in kidney diseases.

EXPERIMENTAL DESIGN

Kidney sections were exposed to exogenous bFGF and then to a monoclonal anti-bFGF antibody. Specificity of the interaction between HS and bFGF was established by monitoring concomitant loss of bFGF during selective removal of HS with heparitinase and competitive inhibition studies. To further characterize regional changes in saccharide sequences, heparitinase-generated unsaturated disaccharides, N-sulfated glucosamine-enriched but O-sulfate-scarce portions characteristics of native HS, and such portions characteristic of Engelbreth-Holm-Swarm tumor HS were studied.

RESULTS

HS was detected in interstitial fibrosis and in advanced glomerulosclerosis, whereas bFGF-binding domains were found only in the fibrosis: The distributional pattern of the N-sulfate-enriched and O-sulfate-scarce portions of native HS was similar to that of bFGF-binding domains. Moreover, a small population of parenchymal cells in advanced tubulointerstitial fibrosis with marked cellular infiltration were especially rich in the bFGF-binding domains.

CONCLUSIONS

In fibrotic lesions of the peritubular interstitium, HS shows enrichment of bFGF-binding domains. These regions may play an important role in the fibrogenesis through their interaction with endogenous bFGF.

Cloning and nucleotide sequencing of a 15 kb region of the Bacillus subtilis genome containing the iol operon

Within the framework of an international project on the sequencing of the whole Bacillus subtilis genome, a 15 kb chromosome segment, which contains the iol operon involved in inositol utilization, has been cloned and sequenced. This region (14,974 bp) contains 12 complete open reading frames (ORFs; genes) and two partial ones; the seventh gene (E83G) is the idh gene encoding inositol dehydrogenase. All the genes identified are transcribed in the same direction as that of the movement of the replication fork. A homology search for their products deduced from the 12 complete ORFs revealed that eight of them exhibit significant homology to known proteins such as fructokinase, acetolactate synthase, fructose-1,6-bisphosphate aldolase (B. subtilis), and PhoB and FtsE proteins (Escherichia coli). It also implied that two genes (B65D and B65E) might encode a set of two-component regulatory proteins and that the B65F gene might encode a protein belonging to the ATP-binding cassette (ABC) family. Based on the features of the nucleotide sequence determined and the results of the homology search, the primary structure of the iol operon is predicted.

Siderophore-mediated utilization of iron bound to transferrin by Vibrio parahaemolyticus

Vibrio parahaemolyticus produces a structurally novel type of siderophore, termed vibrioferrin, in response to iron-limitation. This study was performed to examine whether vibrioferrin can assimilate iron from human iron-binding proteins for growth. Comparison of the growth rates between V. parahaemolyticus AQ 3354 and its spontaneously arising, vibrioferrin-deficient mutant revealed that vibrioferrin was able to sequester iron from 30% iron-saturated human transferrin for growth, but not from human lactoferrin even if fully saturated with iron. In both strains, iron limitation induced two high-molecular-weight outer membrane proteins with apparent molecular masses of approximately 78 and 83 kDa. Since only the outer membrane fraction including these proteins showed a binding capacity to ferric vibrioferrin complex, either of them may function as its cell surface receptor. These results suggested that the organism might utilize such a source of host iron through the action of vibrioferrin during in vivo survival and proliferation, although its importance in pathogenesis is unknown.

Characteristics of partially purified prolidase and prolinase from the human prostate

Both prolidase and prolinase from the human prostate were separated into two peaks by TSK DEAE-5PW chromatography. These peaks of prolidase isozymes I and II differed from each other in their responses to preincubation with Mn2+, their substrate specificity, optimal pH, and heat stability. The molecular weights of prolidases I and II were estimated to be 110,000 and 165,000, respectively, by gel filtration. Substrate specificity of prolinase peaks I and II was almost the same, but they differed in optimal pH and heat stability. The molecular weights of prolinases I and II were about 85,000 and 63,000, respectively. These results indicate that two isozymes of prolidase and of prolinase, which differ in various characteristics, are present in the human prostate.

Primary malignant fibrous histiocytoma of the diaphragm: report of a case

We present herein the case of a 55-year-old man with primary malignant fibrous histiocytoma (MFH) of the diaphragm. He was admitted to our hospital with right anterior chest pain, where diagnostic imaging showed a huge tumor in the right diaphragm with a tumor thrombus in the vena cava, spreading to the left lobe of the liver and the pericardium. Although invasion into the right lung was identified at the time of surgery, the entire tumor was removed. Histopathological examination of the resected specimen revealed the characteristics of MFH. We discuss the clinical features of this patient in comparison with the few previous reports on MFH of the diaphragm.