[A clinical study on treatment results of apicoectomy]

In this study, the treatment results of apicoectomy with orthograde filling were compared with those of apicoectomy with retrograde gutta-percha filling and retrograde sponge gold filling. The long-term follow-up results of the teeth treated by apicoectomy are presented, and the possible prognostic factors are discussed. The healing process of the apical bone cavity was analyzed with standard X-ray techniques and image analysis system. One hundred nineteen teeth were apicoectomized with orthograde filling, 196 teeth with retrograde gutta-percha root filling and 42 teeth with sponge gold filling. There was no significant correlation between the treatment results and the sex or age of the patients, kinds of teeth, preoperative radiolucent areas, the number of operations or histopathological diagnosis of apical lesion. The success rate of apicoectomy with orthograde filling or apicoectomy with retrograde gutta-percha root filling was significantly higher than that with retrograde sponge gold filling. The filling materials and the operation method were considered to be the most important factors for a successful outcome. Bone reconstruction was found to start from the periphery of the bone cavity and the bone defect became gradually reduced in a star-like pattern. At 4 months after operation, in the successful cases, the area of bone cavity decreased 46-64% compared with before operation, but in the unsuccessful cases, the area did not change or increased 75-120%. Thus at 4 months after operation, it is possible to determine whether or not apicoectomy is successful.

Increased serum and urinary neopterin in nephrotic syndrome indicate cell-mediated immune dysfunction

T-cell-mediated immune disturbances are likely but not certain to cause the nephrotic syndrome. Because neopterin (NP) production is closely related to activation of cell-mediated immunity, we addressed the question by measuring serum NP concentrations and urinary NP/creatinine (Cr) ratios, as well as by assessing interstitial lymphocyte and monocyte infiltration in the kidney and activation of the same cell types in peripheral blood. Finally, we observed whether urinary NP/Cr ratios in nephrotic syndrome are changed by steroid therapy. Seventy-four patients with primary glomerulonephritis were divided into 4 groups based on presence or absence of nephrotic syndrome and presence or absence of mesangial proliferation and expansion. Serum and urinary NP concentrations were measured chromatographically. Infiltrating cells in the kidney were identified by immunohistochemistry, and activation of peripheral blood cells was examined by fluorescent surface marker antibodies and flow cytometry. Irrespective of the pathohistology of glomeruli, nephrotic groups showed significantly higher urinary NP/Cr ratios and serum NP concentrations. Nephrotic groups also exhibited more activation of T cells in peripheral blood than did nonnephrotic groups or a healthy control group. Serum NP did not correlate with extent of interstitial renal infiltrates. Steroid therapy decreased urinary NP/Cr ratios in steroid-responsive patients, but not in steroid-resistant patients. Increased serum NP concentrations and urinary NP/Cr ratios may reflect disordered cell-mediated immunity in the nephrotic syndrome, irrespective of glomerular histology or interstitial cell infiltration.

Increased transforming growth factor-beta2 expression in the glomerular arteriole of the juxtaglomerular apparatus in a Bartter's-like syndrome

Although transforming growth factor-beta (TGF-beta) has been shown to participate in regulating hormone synthesis and release, little is known about involvement of individual human TGF-beta isoforms, TGF-beta1, -beta2, and -beta3, in renin synthesis and release. We examined expression of these TGF-beta isoforms in a 50-year-old man with a Bartter's-like syndrome whose renal biopsy specimen showed hyperplasia of the juxtaglomerular apparatus (GA), mild mesangial hypercellularity, focal tubular atrophy, and interstitial fibrosis. Immunoreactivity for renin and marked expression of TGF-beta2 mRNA were noted in the glomerular arteriole of the JGA, whereas mRNA expression for TGF-beta1 was only slight and that for TGF-beta3 was still more faint. Expression of mRNAs for all 3 TGF-beta isoforms was increased in the fibrotic interstitium. This expression pattern suggests that TGF-beta2 may be involved in inducing renin synthesis and/or release in the glomerular arteriole of the JGA.

A high-fat diet aggravates tubulointerstitial but not glomerular lesions in obese Zucker rats

BACKGROUND

Despite a large body of evidence that manipulation of dietary fat alters glomerular lesions, reports regarding the effects of dietary fat on tubulointerstitial lesions are limited. Obese Zucker rats (OZR) spontaneously develop glomerular and tubulointerstitial lesions in association with hyperlipidemia. We sought to elucidate the effects of dietary fat on glomerular and tubulointerstitial lesions in OZR versus lean Zucker rats (LZR) and to assess the involvement of macrophages in the development of these lesions.

METHODS

We fed LZR and OZR either a low- (1%) or high-fat (20%) diet. After 30 weeks of the specified diet, the creatinine clearance (Ccr) and renal histology as well as plasma lipid concentrations were examined. For morphological evaluation, glomerular sclerosis (GSI) and tubulointerstitial indices (TII) were each determined by a point-counting method. Infiltrating macrophages were stained immunohistochemically using an avidin-biotin complex technique.

RESULTS

The high-fat diet increased the plasma low-density lipoprotein concentration in OZR. Both low- and high-fat OZR groups had higher GSI and TII than LZR receiving either diet. The high-fat diet aggravated TII but not GSI or Ccr in OZR; conversely, high fat intake worsened GSI and Ccr but not TII in LZR. Tubulointerstitial macrophages were most prominent in the high-fat OZR group, followed by the low-fat OZR group. Glomerular macrophages were similar in number in all groups.

CONCLUSIONS

The manipulation of dietary fat has diverse effects on the kidney. A high-fat diet aggravated macrophage-mediated tubulointerstitial lesions in OZR, whereas in LZR, the diet induced glomerulosclerosis.

Retrotransposons transcribed preferentially in proximal tubules of salt-hypertensive rats

BACKGROUND

The kidney is considered to play an important etiologic role in salt-sensitive hypertension. The aim of the present study was to isolate genes whose expression differs between the kidneys of salt-hypertensive and control rats using an mRNA differential display method.

METHODS

Dahl salt-sensitive (DS) and control salt-resistant rats (DR) were fed a 0.3% or 8% NaCl diet. Renal RNA was amplified by RNA arbitrarily primed polymerase chain reaction (RAP-PCR) and compared among DR 0.3%, DR 8%, DS 0.3%, and DS 8%. Gene expression and localization were examined by Northern blotting, RNase protection assay, and in situ hybridization. Full-length nucleotide sequence was determined by screening a DS rat kidney cDNA library.

RESULTS

We identified one differentially displayed clone, and its expression was greater in DS than DR, which was not affected by salt loading. The sequence was 90% homologous to the 3'-noncoding region of the nicotinic acetylcholine receptor alpha7 subunit gene. Its expression was kidney-specific, and was localized in the proximal tubules. The transcript level was markedly increased precedent to the development of hypertension. Its expression was also high in other salt-sensitive rats, and low in normotensive Sprague-Dawley and Wistar rats. The full-length cDNA contained elements homologous to the retroviral pol gene, a primer binding site sequence for reverse transcriptase, and long-terminal repeats.

CONCLUSION

These results demonstrated that the newly identified transcripts (REPT1) belong to a novel retrotransposon family, which showed unique strain-, age-, tissue-, and cell type-specific expression pattern.

[A case of an 86-year-old patient treated with thoracoscopic pericardiectomy of recurrent pericardial effusion]

We performed thoracoscopic pericardiectomy to an 86-year-old patient with recurrent pericardial effusion of unknown origin. Etiology of pericardial effusion was established by this procedure. Postoperative course was uneventful. She was discharged within two weeks and has been well 8 months postoperatively. Thoracoscopic surgery is superior to thoracotomy in terms of less invasion and postoperative pain. Thoracoscopic surgery is replacing standard thoracotomy in the management of many thoracic diseases.

Increased levels of transforming growth factor-beta in HIV-associated nephropathy

BACKGROUND

Human immunodeficiency virus-associated nephropathy (HIVAN) is a renal disease of unknown pathogenesis. Recent evidence suggests that the fibrogenic cytokine transforming growth factor-beta (TGF-beta) might be involved. We hypothesized that overproduction of TGF-beta in the kidney might be involved in the pathogenesis of HIVAN.

METHODS

The mRNA and protein expression of TGF-beta isoforms, TGF-beta 1, TGF-beta 2, and TGF beta 3, deposition of matrix proteins induced by TGF-beta, and levels of HIV Tat protein were studied in HIVAN. Controls included normal and diseased kidneys from HIV-positive and -negative patients. The ability of Tat to induce production of TGF-beta and matrix proteins was also studied in human mesangial cells.

RESULTS

Normal kidneys, thin basement membrane nephropathy, and minimal change disease were negative for the three TGF-beta isoforms and Tat. In HIVAN, levels of TGF-beta isoforms and Tat were significantly increased, along with the expression of TGF-beta mRNA and deposition of matrix proteins stimulated by TGF-beta. Increased levels of TGF-beta isoforms, but not Tat, were also found in other glomerular diseases characterized by matrix accumulation. HIV infection, in the absence of HIVAN, was not associated with an increase in TGF-beta or Tat expression. Tat stimulated the expression and production of TGF-beta 1 and matrix proteins by human mesangial cells.

CONCLUSIONS

Our findings suggest that overproduction of TGF-beta is involved in the pathogenesis of HIVAN.

Genomic organization and regulation of expression of the lectin-like oxidized low-density lipoprotein receptor (LOX-1) gene

Lectin-like oxidized low-density lipoprotein receptor (LOX-1) is a recently identified receptor for oxidized low-density lipoprotein, one of the major atherogenic substances. Although LOX-1 was reported to be expressed abundantly in endothelial cells, including atheromatous lesions, the regulation of LOX-1 gene has not yet been clarified. In the present study, we isolated the rat LOX-1 gene and investigated the regulation of gene expression. The rat LOX-1 gene was encoded by a single copy gene spanning over 19 kilobases and consisted of eight exons. Exon boundaries correlated well with the functional domain boundaries of the receptor protein. The promoter region contained putative TATA and CAAT boxes and multiple cis-elements such as NF-kappaB, AP-1 and AP-2 sites, and a shear stress response element. Northern blot analysis revealed that LOX-1 gene expression was up-regulated 9-fold by shear stress, 21-fold by lipopolysaccharide, and 4-fold by tumor necrosis factor-alpha, in cultured vascular endothelial cells. LOX-1 was also expressed in macrophages but not in vascular smooth muscle cells. These data provide important information for elucidating the molecular mechanisms of LOX-1 gene regulation and suggest a role for LOX-1 in the pathophysiology of atherosclerotic cardiovascular disease.

Expression of types I, II, and III TGF-beta receptors in human glomerulonephritis

Protein and mRNA expression of transforming growth factor-beta (TGF-beta) receptor type I (TbetaRI), type II (TbetaRII), and type III (TbetaRIII) were studied in serial sections of kidney samples obtained from patients with glomerulonephritis. In minimal change disease, weak expression of TbetaRI and TbetaRII was observed mainly in glomerular endothelial cells, peritubular capillaries, and interstitial arteriolar endothelial cells, whereas TbetaRIII expression was found mainly in the interstitium. Expression of all three TGF-beta receptors (TbetaR) was increased remarkably in glomerular and Bowman's capsular cells comprising the tuft adhesions to Bowman's capsules in glomerulonephritis with increased matrix accumulation, including IgA nephropathy, lupus nephritis, focal and segmental glomerulosclerosis, myeloperoxidase-antineutrophil cytoplasmic antibody-associated crescentic glomerulonephritis, and membranoproliferative glomerulonephritis. Increased expression of the three TbetaR was also seen in glomerular epithelial cells in the vicinity of glomerulosclerotic lesions, in crescent cells, and in some tubules and infiltrative mononuclear cells found in the periglomerular and tubulointerstitial lesions with increased matrix deposition. In contrast, no remarkable TbetaRII expression was noted in mesangial proliferative lesions in IgA nephropathy, lupus nephritis, and membranoproliferative glomerulonephritis. These data suggest that distinctive modulation of TbetaR expression may be involved in the development of adhesive, sclerotic, and proliferative renal lesions in human glomerulonephritis.

Dipyridamole and dilazep suppress oxygen radicals in puromycin aminonucleoside nephrosis rats

BACKGROUND

Reactive oxygen species (ROS) are involved in the pathophysiology of puromycin aminonucleoside (PAN) nephrosis. To elucidate further the role of radicals in PAN nephrosis and the to determine the particular radical species scavenged by dipyridamole (DPM) and dilazep (DZ), we applied chemiluminescence and electron spin resonance (ESR) techniques.

METHODS

Chemiluminescence of glomeruli, which were isolated on day 7 from rats injected with 100 mg kg-1 PAN, was measured with or without scavengers. The inhibitory effects of DPM and DZ on hydroxyl radical adduct formation in the Fenton's reaction were evaluated using ESR.

RESULTS

Chemiluminescence was greater in glomeruli from rats with PAN nephrosis than in the the glomeruli of control rats. This increase was suppressed by superoxide dismutase, catalase, dimethylthiourea and also by DPM and DZ. ESR indicated that DPM and DZ inhibited hydroxyl radical adduct formation with a second-order rate constant of 2.9 x 10(10) and 1.6 x 10(10) (mol L(-1) s(-1) respectively, similar to that of dimethylthiourea.

CONCLUSION

DPM and DZ scavenge hydroxyl radicals, thereby alleviating PAN nephrosis.

Altered anionic GBM components in monoclonal antibody against slit diaphragm-injected proteinuric rats

BACKGROUND

We previously reported that monoclonal antibody (mAb) 5-1-6 bound to renal filtration slits induces massive proteinuria without causing ultrastructural changes in the glomerulus. This study evaluated the underlying mechanisms of the increase in glomerular permeability.

METHODS

The distribution of endogenous albumin and IgG in the glomerular basement membrane (GBM) was studied in in situ drip-fixed glomeruli of Munich-Wistar rats by use of immunogold immunocytochemistry in the presence and absence of mAb 5-1-6. The density of foot process glycocalyx components was estimated by labeling with Limax fluvus lectin- or Helix pomatia lectin-gold complexes. Anionic sites in the GBM were examined by labeling with cationic gold at pH 2.0 or 7.4. Carboxyl groups, which also furnish an anionic charge to the GBM, were examined by specific biotinylation and colloidal gold probe methods. In addition, the infusion-staining of anionic sites was performed by use of ruthenium red in both Munich-Wistar and Wistar rats.

RESULTS

The urinary excretion of albumin and IgG was increased markedly in the treated rats, indicating a non-selective barrier defect. In the control rats, albumin and IgG molecules were mainly located along the inner half of the GBM, and to a lesser degree in the lamina rara externa. In the treated rats, the albumin and IgG moieties were more equally distributed throughout the width of the GBM. Newly appearing, small dense peaks at the outer side of the GBM were evident, indicating a barrier function of outer zone of the GBM and/or epithelial cell layer. No intergroup differences in the density of lectin binding sites on foot processes were seen. The reduction in the number of ruthenium red-positive anionic sites and cationic gold (pH 2. 0)-labeled anionic sites in the lamina rara externa was significant in the treated rats at day 3, indicating a possible alteration of charged proteoglycan in the lamina rara externa. No such changes were seen with cationic gold (pH 7.4)-labeled anionic sites in the GBM. The density of labeled carboxyl groups was significantly reduced in the treated rats relative to the controls.

CONCLUSIONS

These results show that the injection of mAb 5-1-6 induced a perturbation of the charge- and probably the size-selective glomerular filtration barrier. The observed reduction in the levels of various negatively charged substances resulted in massive proteinuria, implying that alteration of target antigens can affect the integrity of the GBM constituents maintaining the normal barrier function.

Japanese sisters with Pfeiffer syndrome and achondroplasia: a mutation analysis

The authors report the rare existence of a family that includes an older sister with Pfeiffer syndrome and a younger sister with achondroplasia. Gene analysis of these patients showed a T341P mutation in the FGFR2 gene in the patient with Pfeiffer syndrome, and a G380R mutation in the FGFR3 gene in the patient with achondroplasia. Both mutations have been reported previously. Their parents had no mutation in either locus. This result suggests the possibility that there may be predisposing factors for different FGFR mutations.

Structure-function relationship of T-2 toxin and its metabolites in inducing thymic apoptosis in vivo in mice

Recently we found that a single administration of T-2 toxin (T-2), a trichothecene mycotoxin, into mice induced DNA fragmentation, a biochemical hallmark of apoptosis, in the thymus. In this study, we investigated the effective chemical structure(s) of T-2-derived metabolites capable of inducing thymic apoptosis in vivo in mice. Metabolic conversion of T-2 to 3'-hydroxy-T-2 toxin (3'-OH-T-2) did not diminish the apoptosis-inducing activity, since essentially the same level of fragmented DNA was detected in the thymus taken from mice injected with either T-2 or 3'-OH-T-2. In contrast, hydrolysis of T-2 and 3'-OH-T-2 at the carbon-4 (C-4) position to HT-2 toxin (HT-2) and 3'-hydroxy-HT-2 toxin (3'-OH-HT-2), respectively, greatly decreased the level of DNA fragmentation. Similarly, hydrolysis of T-2 at the carbon-8 (C-8) position to neosolaniol strongly diminished its ability to induce DNA fragmentation. T-2 tetraol, having no ester groups, was unable to induce apoptosis. Based on the data presented in this study, we concluded that both the acetyl group at the C-4 position and the isovaleryl or 3'-hydroxyisovaleryl group at the C-8 position of the T-2 molecule are important for inducing cell death through apoptosis in the thymus.

Do obesity and non-insulin dependent diabetes mellitus aggravate exercise-induced microproteinuria?

We evaluated the role of obesity in proteinuria by treadmill exercising of simple obese subjects and non-obese subjects with non-insulin dependent diabetes mellitus in whom the albumin excretion rate at rest was within normal range. Non-obese healthy volunteers were studied as the controls. The fractional renal clearances of four endogenous proteins, albumin, IgG, IgG4, and beta2-microglobulin were measured before, during, and after treadmill exercise in 17 simple obese and 15 non-obese diabetic subjects, and in 21 normal subjects. Exercise increased the fractional albumin clearance in all groups. In diabetic subjects, the fractional IgG4 clearance also increased: fractional beta2-microglobulin clearance increased in normal controls and in diabetics. In obese subjects, the fractional clearances of albumin, IgG, and IgG4 were similar to those in normal controls, but fractional beta2-microglobulin clearance was significantly lower. These results suggest that enhanced microalbuminuria in obese subjects is probably of glomerular origin. In normal subjects and diabetics, exercise-induced microproteinuria is probably of both glomerular and tubular origin. Defect in the charge-selective barrier of the glomerular capillary wall has been implicated in diabetics. Thus some additional factors relevant to obesity must be taken into account in the consideration of the mechanism of microalbuminuria in diabetics with obesity.

MPO-ANCA-positive crescentic necrotizing glomerulonephritis and tubulointerstitial nephritis with renal eosinophilic infiltration and peripheral blood eosinophilia

We present the case of a 67-year-old woman with myeloperoxidase (MPO)-antineutrophil cytoplasmic antibody (ANCA)-positive pauci-immune crescentic necrotizing glomerulonephritis and tubulointerstitial nephritis with renal eosinophilic infiltration and peripheral blood eosinophilia. Staining for eosinophil cationic protein indicated that activated eosinophils were involved in the tubulitis, as well as in the glomerular injury. Marked peripheral blood eosinophilia is uncommon in ANCA-positive crescentic necrotizing glomerulonephritis associated with tubulointerstitial nephritis, except in Churg-Strauss syndrome. However, our patient had no clinical history or signs of asthma, no other signs suggestive of allergic diseases, and no histologic findings of granulomas in the kidney, thus failing to fulfill the criteria for Churg-Strauss syndrome.

Analysis of muscle bioenergetic metabolism in rabbit leg lengthening

The effect of lengthening on muscle metabolism was measured and correlated to the percent lengthening at early and late time points. Using the rabbit tibial lengthening model, the authors examined the effects of lengthening on the tibialis anterior muscle using phosphorus-31 magnetic resonance spectroscopy. Thirty-six rabbits were divided into five groups, four groups by percent lengthening (0%, 15%, 20%, and 25%), with each group divided into subgroups of early (end distraction) and late (12 weeks after end distraction), and the fifth group using the opposite untreated leg as control. Several parameters measuring metabolism of muscle using phosphorus-31 magnetic resonance spectroscopy analysis were compared. No changes occurred to 15% lengthening, but significant decreases were measured at 20% and 25% lengthening. After a 25% lengthening, the decreased metabolism persisted at 12 weeks after distraction, indicating the possibility of permanent damage. After 20% lengthening, the same parameters improved but never to normal levels. The authors conclude that lengthening to 15% is safe for muscle, but 20% to 25% lengthening may result in permanent metabolic damage. The current study also suggests that phosphorus-31 magnetic resonance spectroscopy may provide a viable clinical method for evaluating muscle damage during lengthening.

[Membranoproliferative glomerulonephritis-like lesion with fibrillary deposition associated with multicentric Castleman's disease]

We report a case of a 65-year-old man presenting with multicentric Castleman's disease (MCD) accompanied by membranoproliferative glomerulonephritis-like lesion with fibrillary deposits. The lesion was characterized by highly organized ultrastructual deposits that were negative for Congo-red stain and for immunoglobulin, light chain and C3. Thus, this renal lesion was considered histologically to be fibrillary glomerulonephritis presenting by light microscopy as mesangiocapillary glomerulonephritis. To our knowledge, among the limited number of cases of renal lesion associated with MCD ever reported, this is the first case of a biopsy-proven fibrillary glomerulonephritis. Serum interleukin 6 (IL-6), known as an indicator of MCD activity and as an autocrine growth factor for mesangial cells, was chronologically measured. Augmentation of urinary IL-6 simultaneously with that of extra renal symptoms of MCD and associated renal disease may indicate an underlying role of this cytokine in the present case. Failure to detect of IL-6 in the glomeruli may support the notion that IL-6 is derived from extrarenal lymphonodi, and not to an in situ product of the glomeruli. However, it may have been related to glomerular injury.

Unique repetitive sequence and unexpected regulation of expression of rat endothelial receptor for oxidized low-density lipoprotein (LOX-1)

We report the identification of a unique repetitive sequence in the rat endothelial receptor for oxidized low-density lipoprotein (LOX-1) and unexpected blood-pressure-associated regulation of its expression, a new link between lipid metabolism and blood-pressure control. A rat aorta cDNA library was constructed and screened with a probe synthesized by degenerate PCR. Rat LOX-1 cDNA encoded a protein of 364 amino acids that showed approximately 60% similarity to its bovine and human counterparts. The protein consisted of intracellular N-terminal, transmembrane and extracellular lectin-like domains. Rat LOX-1 was unique in having three repeats of a 46-amino-acid motif between the transmembrane and lectin-like regions. Two isoforms of mRNA were found to be generated by alternative use of two polyadenylation signals in a tissue-specific manner. The 3'-untranslated region contained multiple A+U-rich elements for rapid degradation of mRNA. Northern-blot analysis revealed that LOX-1 mRNA was expressed predominantly in the lung. Quite unexpectedly, the expression was dramatically up-regulated in the aorta in hypertensive SHR-SP/Izm rats compared with very low levels in control WKY/Izm rats, suggesting a potential role for LOX-1 in the pathogenesis of hypertension as well as atherosclerosis.

Source of reactive oxygen species in anti-Thy1 nephritis

In proliferative glomerulonephritis, both macrophages and mesangial cells generate reactive oxygen species (ROS), contributing to the development of glomerular injury. We have attempted to determine which cell produces ROS during anti-Thy1 nephritis (ATN) in rats. The generation of ROS was studied using luminol amplified chemiluminescence (GCL) on isolated glomeruli. Immunohistochemical studies used avidin-biotin complex (ABC) to label macrophages and mesangial cells. Immediately after ATN induction, mesangiolysis and infiltration with ED-1 positive cells (referred to as macrophage) was noted with a peak at day 1. After day 4, mesangial proliferation appeared with a decrease of the ED-1 positive cells and a prominent increase of PCNA positive cells (regarded as mesangial cells). In the early phase of ATN, GCL, reflecting ROS generation, increased along with the appearance of ED-1 positive cells. GCL subsequently decreased as mesangial cells increased. This suggested that macrophage were the principal participants in ROS generation in the early phase of ATN although mesangial cells cannot be completely disregarded in the generation of ROS and development of glomerular injury.

Mutations in fibroblast growth factor receptor 2 gene and craniosynostotic syndromes in Japanese children

We examined the gene mutations of fibroblast growth factor receptor 2 (FGFR2) in Japanese syndromic craniosynostotic patients. Subjects included 1 patient with Apert's syndrome, 1 patient with Crouzon's syndrome, and 3 patients with Pfeiffer's syndrome, as well as two control patients. The genomic deoxyribonucleic acid of each patient was extracted, and the mutation sites of the FGFR2 gene were amplified and sequenced. One patient with Apert's syndrome showed a FGFR2 mutation of S252W (TCG-->TGG), 1 patient with Crouzon's syndrome had a mutation of C342W (TGC-->TGG), and the 3 patients with Pfeiffer's syndrome had mutations of T341P (ACG-->CCG), C342S (TGC-->TCC), and D321A (GAC-->GCC). The role of FGF families and the effect of FGFR2 mutations on craniofacial morphogenesis are discussed.

T-2 toxin induces thymic apoptosis in vivo in mice

A single intraperitoneal injection of T-2 toxin (0.35, 1.75, or 3.5 mg/kg body wt) induced time- and dose-dependent thymic atrophy in young female BALB/c mice. T-2 toxin (1.75 mg/kg) induced maximal atrophy by day 3 with complete recovery by day 7. Flow cytometric analysis showed that the CD4(+)CD8(+) double positive thymocyte population decreased markedly. Histopathological examination of the thymus indicated that the pattern of cell death in the thymocytes had a characteristic apoptotic morphology with cell shrinkage and nuclear condensation. The in vivo effects of T-2 toxin included the induction of DNA fragmentation of approximately 200 base pairs in ladder form and cell death in thymocytes. Furthermore, flow cytometric analysis of PI-stained thymocytes from animals dosed with T-2 toxin revealed the formation of apoptotic cells. Of nine kinds of trichothecene mycotoxins tested, T-2 toxin appeared to be the most potent agent to induce apoptosis in the thymus. We sought insight into the mechanism of T-2 toxin-induced apoptosis in vivo. Administration of the protein synthesis inhibitor, CHX (15 mg/kg ip), 5 min after T-2 toxin (1.75 mg/kg ip) inhibited the induction of apoptosis in thymocytes, suggesting that the de novo protein synthesis was necessary. By using adrenalectomized mice and anti-TNF-alpha antibody-injected mice, it was shown that neither endogenous glucocorticoid nor TNF-alpha appeared to be involved in the apoptotic process. Taken together, these findings suggest that T-2 toxin-induced thymic atrophy is associated with cell death through a mechanism of apoptosis.

Ultrastructural background of albuminuria in rats with passive Heymann nephritis

BACKGROUND

Although it is widely known that proteinuria in rats with passive Heymann nephritis (PHN) is prevented by treatment with cobra venom factor (CVF), the precise mechanisms of complement-dependent proteinuria have not been fully elucidated. The aim of this study was to evaluate morphologically whether the size of subepithelial electron-dense deposits (EDDs) contributes to the onset of albuminuria.

METHODS

The size of subepithelial EDDs and anionic sites in the lamina rarae externa (LRE) overlaid with subepithelial EDDs were evaluated by ruthenium red and compared between PHN and PHN treated with CVF in rats.

RESULTS

Overt albuminuria was present on days 3 and 4 after injection of anti-Fx1A. CVF-treatment of rats with PHN prevented albuminuria (PHN + CVF: n = 6) (53.6 +/- 38.8 vs 1.02 +/- 0.55 mg/day, P < 0.01, on day 4). Rat C3 was detected along the glomerular capillary walls on day 4 post-injection in rats with PHN, but not in rats with PHN + CVF. Subepithelial EDDs were observed in both groups. Quantitative morphometric analysis revealed that CVF-treatment decreased the size of subepithelial EDDs as well as the extent of retraction of glomerular epithelial cells. In both groups the density of anionic sites in the LRE overlaid with EDDs was decreased compared with the LRE without subepithelial EDDs. However, no difference was noted between the two groups.

CONCLUSIONS

Depletion of serum complement decreases subepithelial EDDs as well as the number of sites with decreased anionic charge underlying the EDDs. Thus, the size of subepithelial EDDs plays a pivotal role in the onset of albuminuria.

Inhibitory effects of glucocorticoids on proliferation of canine mast cell tumor

The inhibitory effect of glucocorticoids (GCs) on proliferation of canine mast cell tumor (MCT) was studied using two types of MCT cells; JuMC cells and LuMC cells derived from spontaneous canine cutaneous and intestinal MCT, respectively. In in vitro study, growth of JuMC cells was significantly inhibited with more than 1 nM GCs and apoptotic-like cell death was seen, while that of LuMC cells was never inhibited even with 10 microM GCs. Growth rate of masses in nude mice developed by inoculation of JuMC cells was reduced in a dose-dependent manner by administration of GC, while growth inhibition of masses developed by inoculation of LuMC cells was minimal with increasing GC doses. Competitive binding studies and Scatchard analysis demonstrated the presence of high-affinity, low capacity GC receptors in both JuMC and LuMC cells. Kd was estimated to be 1.30 nM in JuMC cells and 0.45 nM in LuMC cells, respectively. It is concluded that canine cutaneous MCT cells responded to GCs in vitro and in vivo, whereas intestinal MCT cells did not, though both types of cells had specific GC receptors.

Tissue distribution and localization of natriuretic peptide receptor subtypes in stroke-prone spontaneously hypertensive rats

OBJECTIVE

To investigate tissue distribution and localization of the natriuretic peptide receptor (NPR) subtypes' messenger RNA (mRNA) and to compare their expression between stroke-prone spontaneously hypertensive rats (SHR-SP) and Wistar-Kyoto (WKY) rats.

METHODS

Total RNA was extracted from organs of SHR-SP and WKY rats aged 13 weeks. The mRNA level was examined by RNase protection assay. The localization of the transcripts was determined by in-situ hybridization.

RESULTS

In SHR-SP aged 13 weeks, NPR-A was expressed most abundantly in the adrenal gland, lung and aorta, in that order. NPR-B was expressed highly in the uterus and ovary, and also in the lung, adrenal, and brain. NPR-C was expressed predominantly in the atrium and mesentery, less so in the lung, vein, and kidney. In the adrenal gland, NPR-A was expressed mainly in zona glomerulosa cells. In the atrium, NPR-C was expressed throughout the wall. In the mesentery, NPR-C mRNA was detected mainly in adipocytes. In the kidney, NPR-C was found predominantly in podocytes. Whereas the levels of expression of NPR subtypes in most tissues examined did not differ between SHR-SP and WKY rats, the NPR-C mRNA level was significantly greater in the kidneys of SHR-SP than it was in those of WKY rats.

CONCLUSIONS

These results indicated that each NPR subtype had a distinct tissue distribution pattern and that the expression of NPR-C in the kidneys of SHR-SP was greater than that in the kidneys of WKY rats.

Enhanced expression of endothelial oxidized low-density lipoprotein receptor (LOX-1) in hypertensive rats

Oxidized low-density lipoprotein (Ox-LDL) has been implicated in the attenuated endothelium-dependent vasodilatation in atherosclerotic arteries and, possibly, in hypertension. The aim of the present study was to investigate gene expression of recently-identified endothelial Ox-LDL receptor (LOX-1) in hypertensive state. SHR-SP, WKY, Dahl salt-sensitive (DS) and salt-resistant rats (DR) were fed salt-loaded or control diet. RNA was extracted from the aorta and vein. LOX-1 expression was examined by Northern blotting. LOX-1 mRNA was low in the aorta and vein of WKY, whereas it was markedly upregulated in those of SHR-SP. LOX-1 expression was low in the aorta of DR on both diets and of DS on a control diet, whereas it was elevated in that of salt-loaded DS. These results indicated that LOX-1 expression in the aorta and vein was upregulated in hypertensive rats, which may be involved in the impaired endothelium-dependent vasodilation in these rats.

Role of natriuretic peptide receptor type C in Dahl salt-sensitive hypertensive rats

The natriuretic peptide system is suggested to be involved in the pathogenesis of salt-sensitive hypertension; a recent report indicated that disruption of the atrial natriuretic peptide precursor gene caused salt-sensitive hypertension. However, natriuretic peptide receptor (NPR)-A knockout mice did not show enhanced salt sensitivity of blood pressure. The aim of the present study was to investigate the role of NPR-C, the other receptor for atrial natriuretic peptide, in increased salt sensitivity of blood pressure. Dahl salt-sensitive (DS) and salt-resistant (DR) rats were placed on a 0.3% or 8% NaCl diet for 4 weeks. Blood pressure was elevated by salt loading only in DS rats. RNase protection assay demonstrated that NPR-C transcript level in the kidney was reduced by chronic salt loading in both DR and DS rats, whereas expression of NPR-A and NPR-B was not altered. The reduction of NPR-C mRNA in response to salt loading was enhanced in DS compared with DR rats. In situ hybridization indicated that the salt-induced NPR-C change was attributed mainly to suppressed expression of NPR-C in the podocytes. NPR-C gene expression was regulated by salt loading in a tissue-specific manner; the marked decrease in NPR-C mRNA by salt loading was seen only in the kidney. These data suggest that the exaggerated salt-induced reduction of NPR-C in the kidney of DS rats may play an important role in the pathogenesis of salt hypertension in this animal, possibly related to impaired renal sodium excretion.

[Do angiotensin converting enzyme and calcium channel blocker intervene in the progression of renal disease besides by lowering systemic hypertension?]

Systemic hypertension is accompanied by various renal diseases. Lowering of blood pressure is widely recognized effective for slowing further decline of renal function. Angiotensin converting enzyme inhibitor (ACEI) and calcium channel blocker (CCB) have recently emerged as antihypertensive drugs endowed with renoprotective action directed specifically to the kidney. Improvement of glomerular hypertension which is more remarkably observed in ACEI than in CCB, is thought to be a factor responsible for renoprotection. Although this effect is widely shown in experimental models, consensus has not yet been reached as to whether this effect as well as the therapeutic efficacy are really exerted in various clinical settings other than diabetic nephropathy.

[A case of anti-basement membrane (BM) mediated disease presenting renal and pulmonary symptoms by divergent timing]

A case of 49-year-old man with anti-GBM antibody and who manifested pulmonary and renal symptoms at divergent times. Thirty-six years previously, renal disease with unneglectable degree of proteinuria was noticed. One month before admission, he was found by chance to have elevated serum creatine (Scr); 3.4 mg/dl. At admission, his Scr was 13.7 mg/dl and Hb 12.7 g/dl, TP 5.2 g/dl with 3+ proteinuria and no glucosuria. He was a heavy smoker and remained so while admitted. Renal biopsy presented fibrocellular crescents in 100% of glomeruli with striking tubulointerstitial involvement. Immunofluorescence showed linear IgG deposition along the glomerular capillary wall. Hemodialysis was instituted, and after 13 hospital days, anti-GBM antibody at admission was high at 128 U, with negative PANCA. Plasmapheresis was also performed, but on the next day pulmonary hemorrhage occurred with a concomitant rise of anti-GBM to 250 U. Thus, steroid pulse therapy was conducted in combination with plasmapheresis. Pulmonary hemorrhage subsided along with lowering of anti-GBM (48 U), but renal failure persisted. The patient died of septicemia. Based on the clinical course of the case, the term "anti-BM mediated disease" may more properly delineate the entity of the disease rather than the classical eponym "Goodpasture's disease" which requires coexistence of pulmo- and renal manifestations for definition.

Long-term effect of manidipine on renal function and structure in uninephrectomized spontaneously hypertensive rats

1. Long-term effects of manidipine hydrochloride (MAN), a calcium channel blocker, were examined in three groups of spontaneously hypertensive rats (SHR). Group 1 was given uninephrectomy (UNX) and MAN treatment, group 2 was given UNX and was not treated with MAN and group 3 was given neither UNX nor MAN treatment. 2. At week 15 after UNX, inulin clearance in group 1 rats decreased compared with rats in groups 2 and 3, but remained at the same level at week 40, when the level in group 2 rats declined below that in rats in groups 1 and 3. 3. Glomerular and tubulointerstitial lesions did not differ at week 15 after UNX among the three groups, whereas at week 40 both were advanced in the order of groups 2, 1 and 3. 4. Proteinuria did not differ between rats in groups 1 and 2 over the experimental period. 5. At week 15, the kidney weights of group 1 rats were greater than those of group 2 rats, indicating more prominent tubular hypertrophy in the former group. This was confirmed by morphometry of the proximal tubuli. In contrast, the glomerular volumes of rats in groups 1 and 2 were enlarged compared with that of rats in group 3, with no difference between the former two groups. 6. The findings suggest that MAN exerts renoprotective effects in SHR, both with regard to function and morphology. An effect on glomerular haemodynamics was considered to more likely be the mechanism underlying the renoprotective effect of MAN rather than that of a lowering of systemic blood pressure. 7. Augmented tubular hypertrophy after MAN treatment was an unexpected finding of the present study and the biological significance of this finding remains to be explored.

Glomerular handling of immune complex in the acute phase of active in situ immune complex glomerulonephritis employing cationized ferritin in rats. Ultrastructural localization of immune complex, complements and inflammatory cells

The ultrastructural localization of immune complex (IC) and inflammatory mediator systems in the glomerulus was investigated in active in situ IC glomerulonephritis employing cationized ferritin in rats. Glomerulonephritis was induced by unilateral renal perfusion of cationized ferritin as antigen (Ag) in preimmunized rats, and anti-ferritin antibody (Ab), C3 and the rat C5b-9 complex were localized by means of immunogold electron microscopy. Ag-Ab complexes were initially formed subendothelially, associated with C3, and attracted platelets, polymorphonuclear leucocytes (PMN) and monocytes. Then Ag-Ab complexes, without C3, passed across the glomerular basement membrane to re-aggregate subepithelially accompanied by C3 deposition after 1 day. Ag-Ab complexes without C3 accumulated in the inter-podocyte space within 1 day and were seen in the epithelial cells at 6 h. C5b-9 complexes were found in subepithelial immune deposits and in membrane vesicles of the epithelial cells, but only in very small amounts in subendothelial immune deposits. Accumulated platelets, PMN, and monocyte were in direct contact with endothelial cells or subendothelial IC. PMN and monocytes contained Ag, Ab and C3 in intracytoplasmic vacuoles. Ag-Ab complexes were also found in the mesangial matrix adjacent to the subendothelial region after 2 h and increased slightly in number, with expansion of the mesangial area thereafter. Most ICs formed in the subendothelial space rapidly formed lattices of a size that activated C3 and were then translocated to the subepithelial space. The potential ability of C3 to solubilize ICs in the subendothelial region may be important in this process. Endocytosis of subendothelial ICs by PMN and/or monocytes and the movement of ICs to the mesangial matrix may also contribute to the removal of IC from the subendothelial space.

In vivo effect of OPC15161, a superoxide scavenger, on anti-Thy1 nephritis

The in vivo effect of 6-(1 H-indol-3-ylmethyl)-5-methoxy-3-(2-methylpropyl)-2(1 H)-pyrazinone, 4-oxide (OPC15161), a superoxide scavenger, was studied in rats with anti-Thy1 nephritis. Rats were divided into 4 groups: G-1, normal control; G-2, anti-Thy1 nephritis; G-3 anti-Thy1 nephritis and treated with OPC15161 (50 mg/kg/day) starting at day 0; and G-4, anti-Thy1 nephritis and treated with OPC15161 starting 3 days before antibody injection. At weeks 2 and 8, rats were killed for morphological study and at week 8 for renal clearance. Results were compared among the 4 groups. OPC15161 suppressed urinary albumin/day. Total glomerular cells, mesangial cells, ED-1-positive cells/glomerulus and glomerular volume all increased and the increases were suppressed by OPC15161. Tubulointerstitial index, assessed by point counting, was improved by OPC15161 (P < 0.05 G-3, 4, vs. G-2, not significant vs. G-1). Glomerular filtration rate decreased in all nephritic animals, but the decrease in renal blood flow was less in the treated groups. These findings indicate a favorable effect of OPC15161 on the glomerular and interstitial lesions of anti-Thy1 nephritis.

Effects of repeated treatment with methamphetamine plus scopolamine and methamphetamine on behavioral sensitization and conditioning

This study compared repeated treatment with methamphetamine (4.0 mg/kg, i.p.) plus scopolamine (0.5 mg/kg, i.p.) and methamphetamine alone in behavioral sensitization and drug conditioning with respect to a reciprocal balance between the dopaminergic and cholinergic systems. Repeated methamphetamine plus scopolamine treatment induced a more progressive and enduring enhancement of stereotyped behavior than repeated methamphetamine treatment. Methamphetamine plus scopolamine-induced stereotyped behavior was reproduced by challenge injections of not only methamphetamine plus scopolamine and methamphetamine, but also, to a lesser extent, by scopolamine challenges. The methamphetamine plus scopolamine-sensitized rats were conditioned to a low-frequency tone (300 Hz, 100 dB) as conditioned stimulus associated with the drug state. They responded to pairings of the tone and placebo injections, but not to the tone alone or the placebo alone. The methamphetamine-sensitized rats failed to exhibit conditioning. These results suggest that methamphetamine plus scopolamine-induced pronounced behavioral sensitization may produce an enhanced conditioning. Exteroceptive conditioned stimulus-interoceptive unconditioned stimulus associations may provide an important source for drug conditioning. We concluded that behavioral sensitization may be mediated via a reciprocal balance between the dopaminergic and cholinergic systems, in favor of a dopaminergic dominance. Conditioning to the drug-associated tone may operate via a reciprocal balance between the dopaminergic and cholinergic systems.

Local renin-angiotensin system in sympathetic overactivity of spontaneously hypertensive rats

The present study was designed to clarify whether modulation of norepinephrine (NE) release by vascular angiotensin (Ang) II is involved in the increased peripheral sympathetic activity of spontaneously hypertensive rats (SHR). In the perfusion system of isolated mesenteric vascular beds, periarterial nerve stimulation (PNS)-evoked NE overflow was significantly greater in SHR than Wistar-Kyoto rats (WKY). Administration of Ang II increased PNS-induced NE overflow, which could be reversed by pretreatment with the AT1 receptor antagonist CV-11974 in both types of rats; the facilitation by Ang II was more potent in SHR. Moreover, CV-11974 by itself could attenuate PNS-evoked NE overflow, the extent of which was also significantly greater in SHR, suggesting an augmented sympatho-facilitatory effect of endogenous Ang II in SHR. Consistently, sympatho-facilitation by Ang I, which could be abolished by the angiotensin converting enzyme (ACE) inhibitor imidaprilat, was apparently greater than that of Ang II in SHR, despite no difference in WKY. These findings suggest that the increased peripheral sympathetic activity in SHR is attributed not only to the elevated sensitivity of nerve endings to Ang II but also to the increased local generation of Ang II, an effect possibly mediated by augmented vascular ACE activity.

Differential effects of different forms of hydroxyapatite and hydroxyapatite/tricalcium phosphate particulates on human monocyte/macrophages in vitro

A possible complication associated with the use of hydroxyapatite (HA) or HA/tricalcium phosphate (HA/TCP) coating on the surfaces of prosthetic devices used for dental and orthopedic implants is their potential to fragment and thus exist as wear debris. In contrast to the so-called osteoconductive properties of HA or HA/TCP coatings, in particulate form these materials may lead to an adverse pattern of cellular and tissue responses at the bone-implant interface. We have established an in vitro cell culture system to characterize the biologic and biochemical effects of various particulate materials. The present study demonstrates that the HA/TCP particles derived from different sintering temperatures exhibit differential effects on cultured human monocyte/macrophages (M/M). The HA/TCP particles dried at 110 degrees C were the most biologically active, stimulating significant release of interleukin 1 beta (IL-1 beta), IL-6, tumor necrosis factor alpha, and prostaglandin E2 (PGE2), products implicated as important mediators of inflammation in diverse pathologic conditions. Other particles, sintered at either 900 or 1200 degrees C, did not stimulate production of cytokines or PGE2. HA/TCP particles from plasma-spray coatings also failed to release proinflammatory products. These results suggest that the biochemical and crystalline structural properties of particles markedly affects their capacity to modulate M/M function. This in vitro culture system should be useful in characterizing the specific physical and chemical properties of HA or HA/TCP particulates that are responsible for stimulating proinflammatory cell responses.

Interactions of nicardipine to inhalation anesthetics sevoflurane and isoflurane

The hemodynamic effects and pharmacokinetics of nicardipine under general anesthesia were compared between two different volatile anesthetics, sevoflurane and isoflurane. Sixteen adult neurosurgery patients were divided into sevoflurane and isoflurane groups. Anesthesia was maintained with either sevoflurane or isoflurane (0.5-1.5%) and nitrous oxide in oxygen. When the blood pressure was stabilized [0.5 minimum alveolar concentration (MAC) in both anesthetics] during surgery, nicardipine 1 mg, i.v. was administered. Plasma catecholamines and nicardipine concentration were measured, and the pharmacokinetics of nicardipine were calculate. The decrease in blood pressure and the increase in heart rate 30 min after nicardipine administration were significant in the isoflurane group but not in the sevoflurane group. Although plasma catecholamine levels increased after nicardipine administration in the isoflurane group, no significant changes were observed in the sevoflurane group. The sevoflurane group had a significantly longer elimination half-life, a larger area under the plasma concentration curve, and smaller clearance of nicardipine compared to the isoflurane group. In summary, the effects of nicardipine on blood pressure and heart rate were significantly longer under isoflurane anesthesia than under sevoflurane anesthesia. However, the etabolism and excretion of nicardipine were significantly delayed under sevoflurane anesthesia.

Comparison of behavioural effects of repeated treatment with methamphetamine plus scopolamine and methamphetamine alone on behavioural sensitization and conditioned response

We investigated how repeated treatments with methamphetamine (4.0 mg kg-1, i.p.) plus scopolamine (0.5 mg kg-1, i.p.) and methamphetamine alone effected behavioural sensitization and conditioned response in rats. Repeated methamphetamine plus scopolamine treatment induced a more progressive and enduring enhancement of focused stereotyped behaviour than repeated methamphetamine treatment. Stereotyped behaviour induced by methamphetamine plus scopolamine was reproduced by challenge injections of methamphetamine plus scopolamine, methamphetamine, and to a lesser extent by scopolamine challenges. The methamphetamine plus scopolamine-sensitized rats were conditioned to a low frequency tone (300 Hz, 100 dB) associated with the drug state. They exhibited a conditioned response to pairings of the tone (conditioned stimulus) and placebo injections. However, they did not respond to the tone alone or the placebo injections alone. The methamphetamine-sensitized rats failed to demonstrate any conditioning; only the repeated methamphetamine plus scopolamine treatment induced sensitization to the drug-associated tone. Pairings of exteroceptive conditioned stimulus-interoceptive unconditioned stimulus associations may provide an important source for conditioning to the tone associated with the drug state. We conclude that behavioural sensitization may operate via a reciprocal balance between the dopaminergic and cholinergic inhibitory systems, in favour of a dopaminergic dominance. Conditioning to the drug-associated tone may be mediated via a reciprocal balance between the two transmitter systems.

Strain variation in susceptibility to the development of monoclonal antibody 5-1-6-induced proteinuria in rats

Susceptibility to the development of MoAb 5-1-6-induced proteinuria was investigated in four different rat strains, i.e. Brown-Norway (BN), Lewis (LEW), Sprague-Dawley (SD) and Wistar. An intravenous injection of 5 mg of MoAb 5-1-6 to female 7-week-old rats of a given strain induced massive proteinuria in BN, LEW and Wistar rats. However, SD rats developed almost no proteinuria. A similar tendency was observed in the second experiment, in which the injected dose of MoAb was adjusted according to the body weight of each rat (3 mg/100 g body weight). Immunofluorescence (IF) and immunoelectron microscopy (IEM) revealed no differences between the binding patterns of the MoAbs to normal rat kidneys derived from each strain. Quantitative study using 125I-labelled MoAb showed that there was no significant difference in the amount of antibody bound to the kidney 1 h and 5 days after injection between two rat strains, LEW and SD. Localization of 5-1-6 in vivo and its kinetics were investigated. In IF a linear-like pattern along capillary walls was observed 2 h after injection in both LEW and SD strains. This linear-like pattern was shifted to a granular pattern in proteinuric LEW rats 6 days after injection, whereas it remained linear-like in non-proteinuric SD rats. IEM confirmed this difference in the localization of injected MoAb 6 days after injection to LEW and SD rats also at the ultrastructural level. We conclude that there is a clear-cut strain difference in the development of proteinuria induced by MoAb 5-1-6. SD rats were less susceptible to MoAb-induced glomerular injury than BN, LEW and Wistar rats. Although the exact reason for strain variation in susceptibility to MoAb-induced proteinuria remains to be clarified, the movement of bound MoAb, presumably together with corresponding antigenic molecule along the glomerular epithelial cell surface followed by endocytosis into the epithelial cell, seems to be closely related to the induction of proteinuria.

Determination of tributyltin and triphenyltin compounds in hair and fish using a hydrolysis technique and gas chromatography with flame photometric detection

A hydrolysis technique and a GC method are described for the determination of tributyltin and triphenyltin compounds in human hair and fish tissue. A sample was hydrolysed with a potassium hydroxide-ethanol-water solution. Tributyltin and triphenyltin compounds in the hydrolysate were extracted with toluene, and then impurities in the extract were eliminated with anion- and cation-exchange resins. After propylation of the organotin compounds, a yellow impurity was removed with a Sep-Pak florisil cartridge, and the two propylated organotin compounds were separated using a silicone OV-1 GC column and determined by flame photometric detection. The limits of determination of tributyltin and triphenyltin compounds in the sample were 5 and 10 ng g-1, respectively, in their chloride forms. The recoveries of tributyltin chloride from hair samples were 78.8 and 90.8%, respectively, when the spiked amounts were 20 and 200 ng. The recoveries of triphenyltin chloride from hair samples were 71.7 and 72.7%, respectively, when the spiked amounts were 40 and 400 ng. The recoveries of the organotin compounds from fish were similar to the recoveries from hair.

Methamphetamine plus scopolamine potentiates behavioral sensitization and conditioning

The effects of repeated methamphetamine (4.0 mg/kg) plus scopolamine (0.5 mg/kg) treatment on behavioral sensitization and drug conditioning in rats were compared with the effects of repeated methamphetamine treatment. Behavioral sensitization induced by repeated methamphetamine plus scopolamine treatment was more vigorous than that induced by repeated methamphetamine treatment. Repeated methamphetamine plus scopolamine treatment produced sensitized responses, not only to methamphetamine plus scopolamine and methamphetamine but also, to a lesser extent, to scopolamine. Methamphetamine plus scopolamine-sensitized rats but not methamphetamine-sensitized rats exhibited conditioned responses to a low-frequency tone (300 Hz, 100 dB) associated with the drug state, suggesting that robust methamphetamine plus scopolamine-induced behavioral sensitization may lead to enhanced conditioning. It is plausible that robust behavioral sensitization might operate via a reciprocal balance between the dopaminergic and cholinergic systems in favor of dopaminergic dominance. Conditioning to the drug-associated tone may be mediated via a reciprocal balance between the two transmitter systems.

Malignant squamous cell carcinoma arising in a lumbar dermoid cyst. A case report

A case of malignant transformation to a squamous cell carcinoma in a long-standing lumbar dermoid cyst is described. Progress was slow during 6 years. This type of transformation in a dermoid cyst is extremely uncommon and has never been recorded at this site.

[Anesthesia for SUMO wrestlers]

We anesthetized 34 sumo wrestlers. All patients were male. Average age was 21.1. Their height was 181.9 +/- 4.5 (mean +/- SD) cm, and they weighted 135.2 +/- 16.9 kg. Anesthetic methods used were spinal anesthesia alone in 17 patients, general anesthesia alone in 9, general anesthesia + epidural anesthesia/or spinal anesthesia/or axillary block in 8. The preoperative data showed findings common to obese patients; liver dysfunction, abnormal blood sugar, and abnormal ECG such as ST depression or left ventricular hypertrophy. For intubation, fiberscopy was required in one patient, and almost all patients required high FIO2, otherwise SaO2 decreased. For spinal anesthesia or epidural anesthesia, we needed long needles of 8 to 15 cm.

pH-dependent inactivation and reactivation of recombinant sheep angiotensinogen

Purified recombinant sheep angiotensinogen (rsAngn) lost 74% of the reactivity with human renin during storage at pH 8.0 and 4 degrees C. The inactivated rsAngn was reactivated by incubation at acidic pHs. This indicates that pH-dependent inactivation and reactivation occur in rsAngn.

Strychnine poisoning: natural course of a nonfatal case

A rare case of suicidal strychnine poisoning that resolved naturally without treatment is presented. The patient first complained of chest pain, which was originally thought to be caused by a dissecting aneurysm; however, nystagmus, dysesthesia, spastic paraplesia, and hyperreactivity to stimuli shortly developed. Diagnosis was difficult because the patient did not disclose the drinking of strychnine or the suicidal intent, and no abnormal signs were seen in the various central nervous system examinations. The natural course was observed without treatment because the patient's circulatory and respiratory condition was good. Movement disturbances in the upper extremities disappeared after 2 days, nystagmus in 3 days, and dysesthesia and spastic paraplesia in 4 days. The patient was able to stand on the fourth day and walk on the seventh. He was discharged on day 10 without any detectable ill effects.

[Postoperative pain relief by patient controlled analgesia using intravenous pentazocine]

Patient controlled analgesia (PCA) by intravenous pentazocine was performed to determine its efficacy and the dose required for the pain relief after gynecological or obstetric operations. After obtaining informed consent, studies were performed on 28 female patients (ASA I, II: Mean age 38.1 years: Mean weight, 53.8 kg) who had received gynecological or obstetric operations with lower abdominal incision. Anesthesia given was nitrous oxide and isoflurane combined with epidural anesthesia with 1% mepivacaine used only during the operation. Six patients had cesarian section under spinal anesthesia. No patients received opioid during anesthesia. PCA was performed with a Graseby PCA pump. Lockout time was 8 minutes and the bolus dose was 3 mg. In all the patients, satisfactory pain relief was obtained and no other analgesic was necessary. Mean initial dose was 169.4 micrograms.kg-1 and the mean doses used for following each 6 hours until 24 hours were 409.7, 368.6, 279.3 and 211.1 micrograms.kg-1 respectively. Evaluation of PCA by the patients after the procedure showed excellent (13 patients) good (12) and passable (3) analgesia. No significant complication was observed except temporary nausea in two patients. Satisfactory postoperative pain relief could be obtained by relatively small doses of pentazocine and adverse reactions related especially to sigma receptor could be avoided.