Collagenofibrotic glomerulopathy with a widespread expression of type-V collagen

Collagenofibrotic glomerulopathy is considered as a form of glomerulopathy in which organized collagen type III progressively deposits. We report a case of this disease with widespread expression of collagen type V. A 65-year-old woman was admitted to our hospital for further evaluation of nephrotic-range proteinuria. The patient had had anemia and hypertension for 9 years, and proteinuria for 3 years. A renal biopsy specimen showed a remarkable mesangial expansion with Congo red-negative and periodic acid-Schiff-positive deposits. At the ultrastructural level, two forms of bundling fibers were found in the mesangium and subendothelial side of the glomerular basement membranes (GBM). The GBM itself appeared normal. Immunohistochemical investigation showed that the glomerular lesions were strongly reactive with both anti-collagen type-III and -V antibodies. Immunoelectron microscopy demonstrated collagen type V in both forms of bundling fibers. Despite therapy, her renal function declined. The clinical course and renal pathology of this case were in accordance with collagenofibrotic glomerulopathy except for the widespread expression of collagen type V. Collagen type V is a fibrillar collagen capable of forming banding fibrils. This report poses the question whether collagen type V accumulates only in this particular case or whether it is a normal component in collagenofibrotic glomerulopathy.

Mutation analysis of the acid ceramidase gene in Japanese patients with Farber disease

Farber disease is a rare lysosomal storage disease, characterized by the accumulation of ceramide in tissues due to acid ceramidase deficiency. Here we report the identification of three novel mutations in the acid ceramidase gene from two Japanese patients. Patient 1 showed joint problems at around 10 months of age and the patient is now emaciated, with multiple nodules and mild neurological problems at 10 years of age. Patient 2 had consanguineous parents and showed joint contractures at around 8 months of age. He showed neurological symptoms around 2 years of age and died at 6 years owing to respiratory failure. The diagnosis was made clinically and was confirmed by enzymatic assay of acid ceramidase. Molecular analysis of cultured skin fibroblasts showed normal mRNA levels expressed in both patients. By direct sequencing of cDNA, missense mutations of V97E in exon 4 and G235R in exon 9 were detected in patient 1 and 96delV in exon 4 was homozygously identified in patient 2. These mutations were also confirmed in genomic DNA. Expression of mutated acid ceramidase cDNA in COS-1 cells showed acid ceramidase activity decreased to 35%, 2% and 37% of control value, respectively. We also found a new polymorphism V3691 in exon 14 in the allele from the mother of patient 1. To date, 13 mutations, including our newly identified mutations, have been reported. All these mutations were genetically private and genotype-phenotype correlations could not be made.

Cerebral activation by the signals ascending through unmyelinated C-fibers in humans: a magnetoencephalographic study

Cerebral processing of first pain, associated with A delta-fibers, has been studied intensively, but the cerebral processing associated with unmyelinated C-fibers, relating to second pain, remains to be investigated. This is the first study to clarify the primary cortical processing of second pain by magnetoencephalography, through the selective activation of C-fibers, by the stimulation of a tiny area of skin with a CO2 laser. In the hemisphere contralateral to the side stimulated, a one-source generator in the upper bank of the Sylvian fissure (secondary somatosensory cortex, SII) or two-source generators in SII and the hand area of the primary somatosensory cortex (SI) were the optimal configurations for the first component 1M. The onset and peak latency of the two sources in SI and SII were not significantly different. In the hemisphere ipsilateral to the stimulation, only one source was estimated in SII, and its peak latency was significantly (approximately 18 ms on average) longer than that of the SII source in the contralateral hemisphere. From our findings we suggest that parallel activation of SI and SII contralateral to the stimulation represents the first step in the cortical processing of C-fiber-related activities, probably related to second pain.

Clinical significance of caspase-3 expression in pathologic-stage I, nonsmall-cell lung cancer

Caspase-3 is a cysteine protease that plays an important role in the process of apoptotic cell death. Whereas many studies on the clinical significance of apoptosis in the therapy of malignant tumors have been reported, little has been studied clinically on caspase-3. In the present study, the clinical significance of caspase-3 expression in resected nonsmall-cell lung cancer (NSCLC) and its correlation with incidence of apoptosis were examined. A total of 118 consecutive patients who had undergone complete resection for pathologic Stage I NSCLC were retrospectively reviewed. Caspase-3 expression was examined immunohistochemically using a polyclonal antibody that recognized uncleaved caspase-3. The 5-year survival rate for patients with strong expression of caspase-3 (66.6%) was significantly lower than that for patients with weak expression (82.1%, P = 0.021). Expression of caspase-3 was not correlated with incidence of apoptosis, proliferative activity, or p53 status. Multivariate analysis confirmed that strong expression of caspase-3 was a significant factor to predict poor prognosis. These results suggest that enhanced expression of "uncleaved" caspase-3, that is, inactivated caspase-3, was correlated with poor prognosis in resected NSCLC.

A new method of segmental resection for primary lung cancer: intermediate results

OBJECTIVE

To improve the postoperative results of limited resection for small lung cancer, we have developed a new operative method, pulmonary artery-guided segmentectomy. This resection begins with identification of the pulmonary arterial branches involved in the tumor, then the pulmonary tissue is divided along the pulmonary arteries (i.e. guided by pulmonary arteries) from the hilum toward the periphery by electrocautery. The advantages of this method include the facilitation of securing adequate margin from the tumor, and the feasibility of intralobar lymph node dissection during operation. To examine the efficacy of the new method of segmental resection, we retrospectively reviewed 74 cases of T1N0M0 disease who underwent the pulmonary artery-guided segmentectomy.

METHODS

From 1993 to 2000, 74 patients with pathological T1N0M0 lung cancer were treated by the pulmonary artery-guided segmentectomy. Forty-one patients (55.4%) who underwent the segmentectomy had been considered suitable candidates for lobectomy (intentional resection group). The other 33 patients (44.6%) were considered poor candidates for lobectomy because of poor cardiopulmonary reserve (compromised resection group).

RESULTS

The overall survival rate at 5 years was 82.0%. The 5-year survivals in the intentional and the compromised resection groups were 81.6 and 77.6%, respectively, and no significant differences were detected between the groups. According to tumor size, the 5-year survival rate for patients with tumors of 20 mm or smaller (92.9%, n=53) was higher than that for the patients with tumors of 21-30 mm (63.0%, n=21), but the difference did not reach statistical significance. Median follow-up time of 27.0 months revealed eight locoregional recurrences and four deaths due to lung cancer. Sixty-three patients (85.1%) are alive with no evidence of disease, and six patients (8.1%) are alive with recurrent disease. Locoregional recurrences occurred in one of 53 patients (1.9%) with tumors 20 mm or smaller and in seven of 21 patients (33.3%) with tumors 21-30 mm, the difference being statistically significant (P<0.01).

CONCLUSIONS

Our intermediate results demonstrated that the new pulmonary artery-guided segmentectomy could be an alternative method for selected patients with small lung cancer, particularly with tumors 20 mm or smaller in diameter.

[Mid-term outcome of aortic arch operation for true aneurysms; using an axillary artery perfusion]

To prevent cerebral infarction during perioperative period, we have used an axillary artery for systemic perfusion and selective cerebral perfusion for aortic arch operation. Since 1996, 34 aortic arch operations were performed in our institution. Simultaneous 5 CABGs, 4 AVRs, 2 aortic root replacements and 1 MVR were performed. There were 2 hospital deaths (5.9%, sepsis and acute heart failure) and only 1 (2.9%) cerebral infarction. There were no deaths in patients over 75 years of age and in patients with extensive aneurysm which were replaced by 2-staged operation. Overall 3 years survival was 94.1% with no further death. We conclude that aortic arch operation through an axillary artery perfusion and with hypothermic selective cerebral perfusion can be performed with very low mortality and morbidity.

Smooth-muscle calponin in mesangial cells: regulation of expression and a role in suppressing glomerulonephritis

The basic or h1 calponin gene, which encodes an actin-binding protein involved in the regulation of smooth-muscle shortening velocity, is known to be a smooth-muscle differentiation-specific gene. It was found that basic calponin was expressed by cultured mesangial cells and localized along the actin filaments. Among the growth factors involved in the mesangial cell pathophysiology, including platelet-derived growth factor-BB (PDGF-BB), tumor necrosis factor-alpha (TNF-alpha), and transforming growth factor-beta1 (TGF-beta1), TNF-alpha potently downregulates basic calponin expression in both the mRNA and protein levels, whereas TGF-beta1 upregulates the calponin expression. PDGF-BB also reduced its mRNA expression. The half-life of basic calponin mRNA was determined to be similar between TNF-alpha-treated and -untreated mesangial cells, whereas cell transfection assays that used a luciferase reporter gene construct containing the functional basic calponin promoter showed that TNF-alpha and PDGF-BB reduced the transcriptional activity. Because stimulation with TNF-alpha and PDGF-BB was associated with mesangial cell proliferation, basic calponin may play a role in the suppression of mesangial cell proliferation. Treatment with anti-glomerular basement membrane antibody in calponin knockout mice induced more severe nephritis than in wild type mice, as judged from an increase in the urinary protein excretion, glomerular cellularity, and number of proliferating cell nuclear antigen-positive cells in glomerulus. These results suggest that basic calponin expression may serve as one of the intrinsic regulators of glomerular nephritis. Elucidation of the molecular mechanisms for regulation of the basic calponin expression in mesangial cells may improve the understanding of the molecular basis and pathogenesis of the glomerular response to injury.

Evaluation of an office-based urine test for detecting Helicobacter pylori: a Prospective Pilot Study

BACKGROUND/AIMS

To ascertain the reliability of a newly developed office-based urine test, the RAPIRUN test, used for detection of H. pylori infection.

METHODOLOGY

Urine specimens from 142 consecutive patients undergoing gastroendoscopy (77 men, 65 women; mean 52.0 years) were tested with RAPIRUN at the same time. The total reaction time for the urine test is 20 min. None of the patients had received any H. pylori eradicating treatment. The H. pylori status was evaluated based on 5 different tests: culture, histology, biopsy urease test, 13C-urea breath test, and the RAPIRUN test. A commercial office-based kit using an immunochromatographic technique was used to examine urine samples for H. pylori antibody. H. pylori status was defined as positive when the culture was positive or if 2 of the other 3 tests (histology, biopsy urease test, and 13C-urea breath test were positive.

RESULTS

Of 93 patients with H. pylori infection, 88 were tested as positive by RAPIRUN (sensitivity 94.6%). Of 48 patients without infection, 43 were found to be negative by RAPIRUN (specificity 89.6%). One case with an invalid urine test was excluded.

CONCLUSIONS

This urine test is a rapid, inexpensive, reliable and easy-to-use tool for the diagnosis of H. pylori infection in untreated patients. It can be used for mass screening of patients' H. pylori status, particularly in children, postgastrectomy patients, uncooperative patients, and patients undergoing bismuth or proton pump inhibitor treatment.

Upregulation of H(+)-peptide cotransporter PEPT2 in rat remnant kidney

The progression of renal damage resulting from reduced nephron mass has been extensively studied in the 5/6 nephrectomized rat. However, reabsorption of small peptides and D-glucose across the renal proximal tubule in this model remains poorly understood. In this study, we examined the alterations of H(+)-peptide cotransporters (PEPT1 and PEPT2) and Na(+)-D-glucose cotransporters (SGLT1 and SGLT2) in chronic renal failure. Two weeks after surgery, H(+)-dependent [(14)C]glycylsarcosine uptake by the renal brush-border membrane vesicles isolated from 5/6 nephrectomized rats was significantly increased compared with that from sham-operated controls. Kinetic analysis revealed that the maximum velocity value for [(14)C]glycylsarcosine uptake by the high-affinity-type of peptide transporter was increased threefold by 5/6 nephrectomy, without significant changes in the apparent Michaelis-Menten constant value. Competitive PCR analyses indicated that the expression of PEPT2 mRNA was markedly increased in the remnant kidney, but PEPT1, SGLT1, and SGLT2 mRNA levels showed no significant changes. These findings indicated that the high-affinity-type H(+)-peptide cotransport activity is upregulated by 5/6 nephrectomy, accompanied by the increased expression of PEPT2. The upregulation of PEPT2 expression would result in an increase in reabsorption of small peptides and peptide-like drugs across the brush-border membranes in chronic renal failure.

[Long-term outcome after extracorporeal shock wave lithotripsy for gallstones]

We retrospectively reviewed 289 cases followed for a long time after extracorporeal shock wave lithotripy (ESWL) for gallstones. Follow-up periods ranged from 0.5 years to 9.2 years, with a median of 4.1 years. The complete resolution rate was 45.6%. A solitary gallstone, non-calcified gallstones on CT, and Tsuchiya's sonographic type Ia and Ib gallstones were found to be statistically significant variable for resolution of the disease. With a maximum follow-up period of 9 years, the cumulative recurrence rate was 30.7%. Among the 156 patients whose gallstones did not resolve, 70 were symptomatic and the other 86 were asymptomatic. Thirty-eight of the symptomatic patients (54.3%) became symptom-free, while 23 asymptomatic patients (29.1%) became symptomatic. The cumulative rate of occurrence of colic attacks and/or acute cholecystitis was significantly higher in the cases with lithotripsy fragments 4 mm or more in size than in the cases wih fragments 3 mm or less in size (51.8% vs. 16.7%; p < 0.05). ESWL was followed by surgery in 23.1% because symptoms developed or became aggravated after ESWL in 58.3% of them. Gallbladder cancer was discovered in one case. Patients undergoing ESWL should be followed by focusing on postoperative recurrence, symptoms, and gallbladder cancer.

Transport characteristics of grepafloxacin and levofloxacin in the human intestinal cell line Caco-2

Transport characteristics of grepafloxacin and levofloxacin across the apical membrane of Caco-2 cells were examined. Both grepafloxacin and levofloxacin uptakes increased rapidly, and were temperature-dependent. Grepafloxacin and levofloxacin uptakes showed concentration-dependent saturation with Michaelis constants of 3.9 and 9.3 mM, respectively. Uptake of grepafloxacin and levofloxacin increased in Cl(-)-free and ATP depleted conditions, suggesting the involvement of an efflux transport system different from the uptake mechanism. However, cyclosporin A, a typical inhibitor of P-glycoprotein, did not affect the uptake of these drugs. Unlabeled grepafloxacin, unlabeled levofloxacin and quinidine inhibited the uptake of grepafloxacin and levofloxacin under Cl(-)-free conditions. Tetraethylammonium, cimetidine, p-aminohippurate, probenecid, amino acids, beta-lactam antibiotic or monocarboxylates did not inhibit the uptake of grepafloxacin and levofloxacin under the same conditions. In conclusion, our results suggested that grepafloxacin and levofloxacin uptakes were mediated by a specific transport system distinct from those for organic cations and anions, amino acids, dipeptides and monocarboxylates.

Distinct characteristics of organic cation transporters, OCT1 and OCT2, in the basolateral membrane of renal tubules

PURPOSE

This study was performed to determine the detailed mRNA distribution of organic cation transporters, rOCT1 and rOCT2, along the rat nephron and to distinguish the substrate affinities of these transporters.

METHODS

The distributions of rOCT1 and rOCT2 mRNA were determined by reverse transcriptase polymerase chain reaction analysis of microdissected nephron segments. Using MDCK cells transfected with rOCT1 or rOCT2 cDNA, the inhibitory effects of various compounds on the uptake of [14C]tetraethylammonium were assessed.

RESULTS

rOCT1 mRNA was detected primarily in the superficial and juxtamedullary proximal convoluted tubules, whereas rOCT2 mRNA was detected widely in the superficial and juxtamedullary proximal straight and convoluted tubules, medullary thick ascending limbs, distal convoluted tubule, and cortical collecting duct. The IC50 values for cationic drugs and endogenous cations on [14C]tetraethylammonium uptake across the basolateral membranes in the transfectants indicated that rOCT1 and rOCT2 had similar inhibitor specificity for many compounds but showed moderate differences in the specificity for several compounds, such as 1-methyl-4-phenylpyridinium, dopamine, disopyramide, and chlorpheniramine.

CONCLUSIONS

rOCT1 and rOCT2 possess similar but not identical multispecificities for various compounds with distinct distributions along the nephron, indicating that the two transporters share physiologic and pharmacologic roles in the renal handling of cationic compounds.

Structure of human holocarboxylase synthetase gene and mutation spectrum of holocarboxylase synthetase deficiency

Holocarboxylase synthetase (HLCS) is an enzyme that catalyzes the incorporation of biotin into apo-carboxylases, and its deficiency causes biotin-responsive multiple carboxylase deficiency. The reported sequences of cDNA for human HLCS from liver, lymphocyte, and KG-1 myeloid cell lines differ at their 5' regions. To elucidate variations of the human HLCS mRNA and longer 5' cDNA ends, we performed screening of the human liver cDNA library and rapid amplification of the cDNA ends (RACE). Our results suggest the existence of three types of HLCS mRNA that start at different exons. The first type starts at exon 1, and the second type starts at exon 3, and both are found in various human tissues. The third type, corresponding to the cDNA from the KG-1 cell, starts at exon 2 of the HLCS gene. Various splicing patterns from exons 3-6 were also observed. None of the variations of cDNA found created a new initiation codon. Mutation screening from exons 6-14, therefore, was sufficient to detect amino acid changes in HLCS in patients. Our direct sequencing strategy for screening mutations in the HLCS gene revealed mutations in five Japanese patients and seven non-Japanese patients. Our analyses involving 12 Japanese and 13 non-Japanese patients and studies by others indicate that (1) there is no panethnically prevalent mutation; (2) the Arg508Trp, Gly581Ser, and Val550Met mutations are found in both Japanese and non-Japanese populations; (3) the IVS10+5G-->A mutation is predominant and probably a founder mutation in European patients; (4) the 655-656insA, Leu237Pro, and 780delG mutations are unique in Japanese patients; (5) the spectrum of the mutations in the HLCS gene may vary substantially among different ethnic groups.

Evaluation of angiogenesis in non-small cell lung cancer: comparison between anti-CD34 antibody and anti-CD105 antibody

PURPOSE

Angiogenesis is an essential process in the progression of malignant tumors. Whereas pan-endothelial markers, such as CD34, are generally used in evaluation of angiogenesis, pan-endothelial antibodies react with not only "newly forming" vessels but also normal vessels just trapped within tumor tissues. It has been recently reported that anti-CD105 antibody preferentially reacts with "activated" endothelial cells in angiogenic tissues. Thus, the superiority of anti-CD105 monoclonal antibody (mAb) in evaluation of angiogenesis of non-small cell lung cancer (NSCLC) was assessed.

EXPERIMENTAL DESIGN

A total of 236 patients with resected NSCLC were retrospectively reviewed. Intratumoral microvessel density (IMVD) was determined with an anti-CD34 mAb (CD34-IMVD) and with an anti-CD105 mAb (CD105-IMVD).

RESULTS

The mean CD34-IMVD and CD105-IMVD were 179.9 and 41.6, respectively. Whereas CD34-IMVD was significantly correlated with the expression of vascular endothelial growth factor (P = 0.003), CD105-IMVD was more closely correlated with vascular endothelial growth factor expression (P < 0.001). The 5-year survival rate of the lower CD105-IMVD patients was 74.9%, significantly higher than that of the higher CD105-IMD patients (60.4%, P = 0.018). Whereas the 5-year survival rate of the lower CD34-IMVD patients seemed higher than that of the higher CD34-IMVD patients (63.7%), the difference did not reach a statistical significance (P = 0.137). Multivariate analysis confirmed that higher CD105-IMVD was a significant factor to predict poor prognosis (P = 0.029), whereas CD34-IMVD was not (P = 0.070).

CONCLUSIONS

Anti-CD105 mAb proved to be superior to anti-CD34 mAb in evaluation of angiogenesis in NSCLC.

Conduction velocity of the spinothalamic tract in humans as assessed by CO(2) laser stimulation of C-fibers

We measured the conduction velocity (CV) of C-fibers in the spinothalamic tract (STT) following stimulation with a CO(2) laser using a new method. We delivered non-painful laser pulses to tiny areas of the skin overlying the vertebral spinous processes at different levels from the 7(th) cervical (C7) to the 12(th) thoracic (T12), and recorded cerebral evoked potentials in 11 healthy men. We used the term "ultra-late laser evoked potentials" (ultra-late LEPs), since the peak latency was much longer than that for conventional LEPs related to Adelta-fibers following painful laser stimulation (late LEPs). The mean CV of C-fibers in the STT was 2.2+/-0.6 m/s, which was significantly lower than the CV of the Adelta-fibers (10.0+/-4.5 m/s). This technique is novel and simple, and should be useful as a diagnostic tool for assessing the level of spinal cord lesions.

[Effect of probucol on the concentration of cyclosporin A in patients with nephrotic syndrome]

The first choice of therapy for nephrotic syndrome is steroid, and cyclosporin A(CyA) or other immunosuppressants are selected for steroid resistant or recurrent cases. Nephrotic syndrome accompanies hyperlipidemia for which HMG-CoA reductase inhibitors are mainly used. On the other hand, probucol is used in cases showing inadequate effects or some adverse reactions under treatment with HMG-CoA reductase inhibitors. Recently, we experienced several cases whose blood levels of CyA were decreased to about half that before the combined use of probucol, and concomitant administrations were discontinued. Based on these cases, we considered that the use of probucol should be prescribed in patients with nephrotic syndrome accompanying hyperlipidemia giving preference to CyA treatment. In cases of unavoidable usage of probucol, CyA dose adjustments are required on the basis of frequent CyA blood level monitoring.

Distinct transport characteristics of basolateral peptide transporters between MDCK and Caco-2 cells

The cellular polarity of [14C]glycylsarcosine (Gly-Sar) transport in Madin-Darby canine kidney (MDCK) cells was compared with that in the human intestinal cell line Caco-2. In MDCK cells, [14C]Gly-Sar accumulation was greater at the basolateral side than at the apical side, and there was little net transcellular transport. In Caco-2 cells, [14C]Gly-Sar accumulation was greater at the apical side and unidirectional transcellular transport occurred from the apical to basolateral side. Efflux of [14C]Gly-Sar from MDCK cells to either side was negligible, whereas that from Caco-2 cells was significantly faster to the basolateral side. The basolateral peptide transporter in MDCK cells possessed a similar substrate specificity, but a much higher substrate affinity, than that in Caco-2 cells. The basolateral peptide transporter in MDCK cells did not accumulate Gly-Sar during hypertonic stress. These findings indicate that the basolateral peptide transporter in MDCK cells is involved in the cellular uptake of small peptides, but not in the extrusion of small peptides to the extracellular space.

Multispecific substrate recognition of kidney-specific organic anion transporters OAT-K1 and OAT-K2

We characterized the interactions of various compounds with OAT-K1 and OAT-K2, kidney-specific organic anion transporters. By using Madin-Darby canine kidney cells stably transfected with OAT-K1 or OAT-K2 cDNA, the antitumor drug methotrexate, the mycotoxin ochratoxin A, endogenous organic anions (thyroid hormones, taurocholic acid, and conjugated steroids), and the antiretroviral drug zidovudine were shown to be substrates for these transporters. Although the apparent Michaelis constant (Km) values of methotrexate for OAT-K1 and OAT-K2 were 2.1 and 1.8 microM, respectively, 2.5 mM methotrexate inhibited only 20% of the 125I-thyroid hormones uptake via these transporters. In addition, 100 microM methotrexate did not have any effect on [3H]zidovudine uptake via OAT-K1 or OAT-K2. Similarly, several substrates caused little or no mutual inhibition at concentrations much higher than their Km values for these transporters. Moreover, intracellular methotrexate trans-stimulated the OAT-K1- and OAT-K2-mediated uptake of [3H]folic acid, but not that of other compounds. Organic anion-transporting polypeptide 2 (oatp2), a liver-type homolog of OAT-K1 and OAT-K2, showed similar events. The inhibition constant values of triiodothyronine and taurocholic acid for [3H]digoxin uptake in oatp2-expressing oocytes resulted in 50.4 and 1.48 mM, respectively, which were about 9- and 40-fold higher than their Km values for oatp2, respectively. These findings suggested that several substrates interact with these transporters at different amino acid residue(s). Taken together, these observations suggested that OAT-K1 and OAT-K2 could serve as multispecific transporters, mediating transport of a wide variety of endogenous substances, xenobiotics, and their metabolites in the kidney, presumably via several interaction sites in their molecules.