Long-term results of ABO-incompatible living kidney transplantation: a single-center experience

BACKGROUND

Despite great efforts to promote the donation of cadaveric organs, the number of organ transplantations in Japan is not increasing and a serious shortage of cadaveric organs exists. These circumstances have forced a widening of indications for kidney transplantation. For this purpose, ABO-incompatible living kidney transplantations (LKTs) have been performed. Although we have already reported the short-term results of ABO-incompatible LKT, there is no report of long-term results in such cases; anti-A and anti-B antibodies could cause antibody-induced chronic rejection and result in poor long-term graft survival. In this study, we have reviewed the long-term results of ABO-incompatible LKT and tried to identify the most important factors for long-term renal function in ABO-incompatible LKT.

METHODS

Sixty-seven patients with end-stage renal failure underwent ABO-incompatible living kidney transplantation at our institute between January, 1989, and December, 1995. The mean age was 34.9 years (range, 8-58 years), with 38 males and 29 females. Incompatibility in ABO blood group antigens was as follows: A1-->O, 23 patients; B-->O, 19 patients; A1B-->A1, 7 patients; B-->A1, 8 patients; A1-->B; 4 patients; A1B-->B, 4 patients; A1B-->O, 2 patients. The number of HLA-AB, and -DR mismatches were 1.6+/-1.1 and 0.76+/-0.6, respectively. Plasmapheresis and immunoadsorption were carried out to remove the anti-AB antibodies before the kidney transplantation. In the induction phase, methylprednisolone, cyclosporine, azathioprine, antilymphocyte globulin, and deoxyspergualin were used for immunosuppression. Local irradiation of the graft was performed at a dose of 150 rad, on the first, third, and fifth days after transplantation. Splenectomy was done at the time of kidney transplantation in all cases.

RESULTS

Patient survival was 93% at 1 year and 91% at 8 years. Graft survival was 79% at 1, 2, 3, and 4 years, 75% at 5 and 6 years, and 73% at 7 and 8 years. Patient survival was not significantly different from that of ABO-compatible patients. However, graft survival was significantly different between ABO-incompatible grafts and ABO-compatible grafts. Specifically, ABO-incompatible transplant recipients experienced a significantly higher rate of early graft loss up to 3 years but showed an equivalent graft loss by year 4. Among 67 patients, 16 grafts were lost during the observation period. Loss was due to acute rejection in 5 patients, followed by chronic rejection in 5 patients and death with function in 3 patients, whereas immunosuppression was withdrawn in 3 patients due to nonimmunological reasons. Of 16 grafts lost, 15 were lost within 1 year after transplantation. Of the 67 patients, 5 died during observation. Three patients with functioning grafts died of uncontrolled bleeding due to duodenal ulcer, malignant lymphoma, and cerebral hemorrhage (one patient each). One patient died of ischemic colitis due to secondary amyloidosis and one patient of cerebral hemorrhage after graft loss due to humoral rejection. There was no fatal infectious complication, whereas 10 patients had non-tissue-invasive cytomegalovirus infection. The stepwise logistic regression model was employed to identify the most important factors for long-term renal function. Patients were subdivided into those with serum creatinine of less than 2.0 mg/dl (group 1, n=39) versus those with serum creatinine of more than 2.0 mg/dl (group 2, n=22) at one year after renal transplantation. Six patients were excluded because of death with functioning graft (three patients) and withdrawal of immunosuppression (three patients). Rejection episodes within 6 months were significantly frequent in group 2 compared with group 1 (P=0.0008). Odds ratio was 112-fold in the rejection episodes. Obviously, the high incidence of early humoral rejection is caused by ABO incompatibility, because ABO-incompatible grafts experience a higher rate of early rejection and graft loss compa

The importance of polymorphonuclear leukocytes in lipopolysaccharide-induced superoxide anion production and lung injury: ex vivo observation in rat lungs

The purpose of this study is to determine if the polymorphonuclear leukocyte (PMN) is a major causative agent for lipopolysaccharide (LPS)-induced lung injury and responsible for the excess production of superoxide anion in the lung. We measured superoxide anion production from the lung and pulmonary capillary permeability in rats with and without PMN depletion. The superoxide anion production from the lung was measured using a purpose-built ex vivo chemiluminescence apparatus. Pulmonary capillary permeability was evaluated by the Evans blue dye extravasation method. PMN sequestration was determined by counting PMNs in histologic tissue specimens using microscopy. All rats received 3 mg/kg LPS intravenously. Examinations were undertaken at 2, 6, and 12 h after the LPS injection. The PMN-depleted group received cyclophosphamide 4 days before the LPS injection, which resulted in a PMN count of less than 200 cells/microliter. In rats without PMN depletion, Evans blue dye extravasation increased significantly at 12 h after the LPS injection; PMN sequestration increased at 2, 6, and 12 h after the LPS injection; and superoxide anion production increased at 6 h and remained elevated at 12 h after the LPS injection. The increased permeability, PMN sequestration, and superoxide anion production were not seen in the PMN-depleted group. The contribution of the xanthine/xanthine oxidase system and alveolar macrophages to the observed superoxide anion production was negligible. We conclude that, in rats, the PMN is a major causative agent in LPS-induced lung injury and is responsible for the excess production of superoxide anion in the lung.

Growth arrest of immortalized human keratinocytes and suppression of telomerase activity by p21WAF1 gene expression

Because most non-melanocytic human skin cancers have p53 mutations, it is unclear whether the aberrant growth of these cancers is simply a result of the abrogation of a p53 downstream mediator, the universal cyclin-dependent kinase inhibitor p21WAF1. To investigate the role of p21WAF1 in human skin carcinogenesis, we studied its regulation in normal and p53-mutated immortalized human keratinocytes. In proliferating human normal keratinocytes (HNK), more wild-type p53 protein (wt p53) was expressed than in growth-arrested differentiating keratinocytes. However, the function of wt p53 as a transcriptional activator of the p21WAF1 gene was suppressed in proliferating keratinocytes. In response to ultraviolet B irradiation, expression of wt p53 increased in proliferating keratinocytes, but p21WAF1 transcriptional activation was not induced. Two isoforms of mdm2 (p57 and p90), which can bind to wt p53 and negatively regulate wt p53 function, were expressed in proliferating HNK, suggesting that mdm2 may play a role in the suppression of wt p53's function in proliferating HNK. Increased expression of p21WAF1 was detected in both Ca(2+)-induced growth-arrested and differentiating HNK, in which the wt p53 expression was down regulated. This reflects the complexity of the p53/p21WAF1 pathways of cell-cycle regulation and differentiation in keratinocytes. No p21WAF1 expression was detected in human immortalized keratinocytes (HaCaT) or in two ras-transformed variants, HaCaT ras I/7 and HaCaT ras II/3, which have two p53 mutations. Retrovirus-mediated expression of p21WAF1 stopped the growth of all these cell types, but expression of wt p53 did not affect the cells' growth properties. p21WAF1 also downregulated human telomerase RNA component mRNA expression in HaCaT cells. This novel function of p21WAF1 partly explains the suppression of telomerase activity by p21WAF1 expression in HaCaT. Taken together, these results are consistent with the idea that p21WAF1 successfully inhibits the growth of non-melanocytic skin cancers, even those with alterations in p53, p21ras, retinoblastoma gene product, and telomerase activity.

[Immediate burn wound excision and grafting decreases the mortality rate and hospital stay duration in extensive burn patients]

The treatment of patients with extensive burn injuries has begun to changed in recent years. Traditional methods have consisted of dressing the burn wound with topical antimicrobials, tubbing the patient daily, encouraging the shoughing off of eschar using surgical debridement as necessary, and finally, closing the granulating wound with split-thickness skin grafts after 2 to 4 weeks. An alternative and more radical procedure is now being used with increasing frequency: complete surgical excision of the eschar is performed as soon as the patient is hemodynamically stable after resuscitation from burn shock. From 1991 to 1997, we performed immediate burn wound excision and grafting in 15 extensive burn patients within 24 hours after injuries. The mean burn surface area (BSA) was 48 +/- 20%, and the mean burn index was 44 +/- 19. The mean prognostic burn index (PBI = burn index + age) was 94 +/- 23. There were 5 deaths, for an overall mortality rare of 33%, which is less than that experienced by 11 other burn units in Tokyo (51.4%). The duration of hospital stay of survivors was approximately 1 day/%BSA.

The effect of dialysate glucose on phagocyte superoxide generation in CAPD patients

OBJECTIVE

In the present study, we investigated the influence of dialysate glucose on superoxide (O2-) generation by peripheral and peritoneal phagocytes in continuous ambulatory peritoneal dialysis (CAPD) patients.

DESIGN

Peripheral polymorphonuclear leukocytes (PMNL) and mononuclear leukocytes (MNL), and peritoneal cells were isolated from peripheral blood and peritoneal effluents, respectively, and their oxidative metabolism was assessed by measuring O2- generation after stimulation with a soluble stimulant [phorbol myristate acetate (PMA), 1 mg/mL, Sigma Chemical, St. Louis, MO, U.S.A.] using the chemiluminescence method. Dialysate glucose effect on O2- generation was also studied in vitro by exposing peripheral PMNL and MNL from healthy controls to peritoneal dialysis fluid (PDF) containing glucose or amino acids at a neutral pH for different time periods.

RESULTS

The amount of O2- generation by both peripheral and peritoneal phagocytes in CAPD patients was significantly higher than that in the control, and the response was greater in patients who were dialyzed with high glucose dialysate than those using low glucose dialysate. In an in vitro study, all incubated cells, except the control, showed suppression of O2- generation in the early dwell time (2 hr), and subsequently showed increased responses (peaking at 6 hr), although lower in degree than those observed in vivo. In contrast, amino acid-based PDF exhibited no such effect on O2- generation at identical pH with similar or lower osmolality. Furthermore, the respective increased or decreased oxidative responses with the increased or decreased PDF glucose concentrations in the same patient confirmed the positive effect of PDF glucose on phagocyte O2- generation.

CONCLUSION

It is suggested that increased O2- generation by peritoneal and circulating phagocytes in CAPD patients is at least partly due to the enhancement of hexose monophosphate shunt activity by increasing glucose metabolism in phagocytes, and the increased O2- generation might be involved in long-term complications of CAPD. Therefore, a suitable alternative osmotic agent is needed to provide a more physiological environment to minimize the adverse effects of glucose on cell functions.

Nitric oxide inactivates NADPH oxidase in pig neutrophils by inhibiting its assembling process

The effects of nitric oxide (NO) on superoxide (O-2) generation of the NADPH oxidase in pig neutrophils were studied. NO dose-dependently suppressed O-2 generation of both neutrophil NADPH oxidase and reconstituted NADPH oxidase. Effects of NO on NADPH-binding site and the redox centers including FAD and low spin heme in cytochrome b558 and the electron transfer rates from NADPH to heme via FAD were examined under anaerobic conditions. Both reaction rates and the Km value for NADPH were unchanged by NO. Visible and EPR spectra of cytochrome b558 showed that the structure of heme was unchanged by NO, indicating that NO does not affect the redox centers of the oxidase. In reconstituted NADPH oxidase system, NO did not inhibit O-2 generation of the oxidase when added after activation. The addition of NO to the membrane component or the cytosol component inhibited the activity by 24.0 +/- 5.3 or 37.4 +/- 7.1%, respectively. The addition of NO during the activation process or to the cytosol component simultaneously with myristate inhibited the activity by 74.0 +/- 5.2 or 70.0 +/- 8.3%, respectively, suggesting that cytosol protein(s) treated with myristate becomes susceptible to NO. Peroxynitrite did not interfere with O-2 generation.

Determination of melanin in human hair by photoacoustic spectroscopy

A highly sensitive photoacoustic spectroscopy for the determination of melanin in human hair has been developed. Both synthetic melanin and human hair were treated with 50% sulfuric acid. The melanin suspension was passed through the membrane filter to collect melanin, and the filter was transferred into a homemade photoacoustic cell, followed by measurement of the photoacoustic signals produced by 10 mW He-Ne laser beam. The good correlation between the method described in this paper and absorption spectrophotometry was confirmed quantitatively. The linearity observed between the photoacoustic signal and the weight of samples was in the range of 0.1-20 micrograms for synthetic melanin and 10-800 micrograms for human hair, with detection limits of 5 ng and 0.38 microgram, respectively.

[A case of primary acute pulmonary cavitation in sarcoidosis complicated by multiple nodular lesions in the central nervous system]

A 20-year-old man visited our hospital complaining of headache and a dry cough. Chest X-ray and chest CT showed bilateral hilar and mediastinal lymphadenopathy, multiple cavitations with thin, smooth walls, and diffuse granular shadows. A transbronchial biopsy specimen revealed sarcoid granuloma. Primary acute pulmonary cavitation of sarcoidosis was diagnosed, since there was no evidence of infection, emphysematous change, fibrotic or cystic bronchiectatic change on chest X-ray. EEG, contrast enhancement of brain CT scans and MRI were performed because the patient complained of headache. EEG showed a high voltage paroxysmal slow wave and giant build-up, whereas brain CT showed no abnormalities. T1-weighted MRI with gadolinium enhancement showed multiple high intensity nodules in the convexity, brain stem, and spinal cord. Corticosteroid therapy (60 mg/day) was started. After 1 week of treatment, the headache ceased. After 2 weeks of treatment, both the cavities in the lung field's and the nodules in the central nervous system disappeared. Therefore, the dose of corticosteroids was gradually reduced to a maintenance dose of 5 mg/day, and no relapse was noted. We report a very rare case of primary acute pulmonary cavitation in sarcoidosis complicated by multiple nodular lesions in the central nervous system.

Pigmented human skin equivalent: new method of reconstitution by grafting an epithelial sheet onto a non-contractile dermal equivalent

We have established a new protocol for reconstituting a pigmented human skin equivalent (PSE) and have evaluated its functional responses to environmental stimulus, UVB. The PSE is reconstituted by grafting an epithelial sheet consisting of keratinocytes and melanocytes onto a porous non-contractile dermal equivalent populated with mitotically and metabolically active fibroblasts. i) The PSE has a multilayered, well-differentiated epidermis with cuboidal basal cells and highly organised dermis with newly synthesised extracellular matrix components. ii) Ki67-positive proliferating keratinocytes (18.1 +/- 7.4%) were detected on the basal layer of the epidermis. iii) Melanocytes located exclusively within the basal layer were detected by monoclonal antibody against tyrosinase-related protein (TRP-1). iv) After exposure to UVB (100 mJ/cm2 per day) for 7 consecutive days, the intensity of TRP-1 staining was increased in the PSE, showing their functional state, whereas the number of melanocytes was not changed. This non-contractile and functioning new PSE is potentially useful as a model for studying the role of melanocyte-keratinocyte-fibroblast interactions in photoprotection of the skin in more complex cutaneous microenvironment than monolayer culture, and for developing in vitro disease models and therapeutic protocols with genetically altered cells both in epidermis and dermis.

[A case of xanthogranuloma of the urinary bladder]

A case of xanthogranuloma of the urinary bladder is reported. A 68-year-old man was referred to our hospital for the evaluation of microscopic hematuria. At that time, he did not have an abdominal tumor and ultrasonography showed no abnormality of the kidneys and the bladder wall. Two months later, he was admitted with the chief complaints of perineal discomfort and non tender fist size mass was palpable in the lower abdomen. Ultrasonography, computed tomographic scan and magnetic resonance imaging MRI demonstrated a supravesical mass which was strongly suspected as urachal tumor. Total cystectomy with urachal resection was performed. The histological diagnosis was xanthogranuloma. The patient has been in good health without recurrence, 4 years after surgery. We discuss xanthogranuloma of the urinary bladder in the literature.

Patched (ptch)-associated preferential expression of smoothened (smoh) in human basal cell carcinoma of the skin

The discovery of specific overexpression of a gatekeeper gene, ptch, in basal cell carcinoma (BCC) led to a hypothesis that the human homologue of patched (PTCH) normally functions as a negative regulator of the signaling pathway that is initiated by hedgehogs (HHs) and activated by the human homologue of smoothened (SMOH); however, no evidence for the involvement of smoh and hhs has been provided. Here, we show novel evidence that smoh is also preferentially overexpressed in BCC, together with ptch (P < 0.002), and that Sonic hh was expressed in only some BCCs. Our data, therefore, indicate that such overexpression of smoh may be associated with overexpression or mutation of PTCH and that this overexpression subsequently stimulates the PTCH/SMOH signaling pathway. In an investigation of a possible regulation of ptch and smoh, we demonstrated that expression of exogenous p21WAF1 in immortalized keratinocytes down-regulates both ptch and smoh and that the down-regulation is accompanied by growth arrest, which suggests the involvement of p21WAF1 in regulation of the PTCH/SMOH signaling pathway.

Long-term outcome of renal transplantation in hepatitis B surface antigen-positive patients in cyclosporin era

The impact of hepatitis B virus (HBV) infection on the outcome of renal transplantation (Tx) has been controversial. To determine the indication of renal Tx in patients infected by HBV, we investigated the long-term outcome of renal transplant patients with hepatitis B surface antigen (HBsAg). We analyzed 980 patients, including 18 HBsAg carriers, who underwent renal Tx and were immunosuppressed with cyclosporin in our institute. Fourteen out of 18 patients (77.8%) showed hepatic dysfunction after an average period of 17.8 months (range 1-65) after Tx. Four out of 14 patients (28.5%) with hepatic dysfunction died of liver failure due to fulminant hepatitis with functioning grafts between 15 and 71 months after Tx. The remaining 10 patients with hepatic dysfunction are alive up to the time of last follow-up; however, 5 of them lost their grafts because of rejection between 44 and 92 months after Tx. Their liver function improved after withdrawal of cyclosporin. Only 4 patients did not develop chronic liver disease and have had functioning grafts for between 44 and 147 months. One patient died of subarachnoid hemorrhage 22 months after Tx. HBe antigen, antibody and HCV antibody status were not related to the occurrence of liver dysfunction after Tx. Four HBV-DNA-positive patients showed deteriorated liver function. Three patients with chronic active hepatitis confirmed by the biopsy were treated with interferon. Interferon improved liver function in 2 patients, however, 1 patient died of liver failure despite interferon therapy. Our data suggested that the presence of HBsAg is often associated with chronic liver disease leading to liver failure regardless of HBe and HCV status after Tx. The indication of renal Tx in patients with HBsAg should be determined carefully giving consideration to these results.

Nitric oxide mediates murine cytomegalovirus-associated pneumonitis in lungs that are free of the virus

4 wk after intraperitoneal inoculation of 0.2 LD50 (50% lethal dose) of murine cytomegalovirus (MCMV) in adult BALB/c mice, MCMV remained detectable in the salivary glands, but not in the lungs or other organs. When the T cells of these mice were activated in vivo by a single injection of anti-CD3 monoclonal antibody, interstitial pneumonitis was induced in the lungs that were free of the virus with an excessive production of the cytokines. In the lungs of such mice persistently infected with MCMV, the mRNA of the cytokines such as IL-2, IL-6, TNF-alpha, and IFN-gamma were abundantly expressed 3 h after the anti-CD3 injection, and the elevated levels continued thereafter. A marked expression of inducible nitric oxide synthetase (iNOS) was then noted in the lungs, suggesting that such cytokines as TNF-alpha and IFN-gamma may have induced iNOS. Although the increase in NO formation was demonstrated by the significant elevation of the serum levels of nitrite and nitrate, the interstitial pneumonitis was not associated with either increased superoxide formation or peroxynitrite-induced tyrosine nitration. Nevertheless, the administration of an NO antagonist also alleviated the interstitial pneumonitis provoked by anti-CD3 mAb. Based on these findings, it was concluded that MCMV-associated pneumonitis is mediated by a molecule of cytokine-induced NO other than peroxynitrite.

[Telomerase]

Telomerase is an enzyme that elongates telomeric repeats, the specialized structures at the ends of chromosomes that provide genomic stability and compensate for the physiologic process of telomere shortening. It has been implicated in cellular senescence, immortalization, and carcinogenesis. Over 85% of human tumours, and 95% of nonmelanocytic skin cancers, show telomerase activity, in contrast to the corresponding normal tissues. This suggests that telomerase activity may play an important role in carcinogenesis. Recent evidence shows that telomerase is active not only in embryonal and germ line tissues, but also in some normal tissues. In the skin, this activity has been traced to the stem-cell-bearing epidermal basal cell layer, possibly reflecting the presence of telomerase-competent stem cells. These findings require a reconsideration of our interpretation of telomerase activity in tumours of the skin and other tissues. As a causal relationship linking telomerase activity and cancer has yet not been demonstrated, some caution is warranted.

New method to measure the carbamoylating activity of nitrosoureas by electron paramagnetic resonance spectroscopy

A new method for measuring the carbamoylating activity of nitrosoureas and isocyanates using electron paramagnetic resonance (EPR) spectroscopy is described. The extent and time course of carbamoylation reaction of chloroethyl isocyanate and a series of 9 nitrosoureas toward amino group of 4-amino-2,2,6,6-tetramethyl-piperidine-1-oxyl were examined with both the EPR method and the HPLC method which has been proposed by Brubaker et al. [Biochem. Pharmacol. 35:2359 (1986)]. Spin-labeled nitrosoureas we synthesized are included in this study since they have less toxicity or more efficiency than commercially available drug in some cases. The concentration of carbamoylated product was easily determined with the EPR spectra. There is a very high correlation (r = 0.982, t = 2.58, N = 10, p < 0.001) between the EPR and HPLC methods. Spin-labeled nitrosoureas showed lower carbamoylating activity than non-labeled analogues. The carbamoylating activity for these nitrosourea depended on the reactivity of isocyanate intermediate and almost independent of their half life. This rapid and simple EPR method is suitable for the detailed investigation of the rate and extent of carbamoylation reaction.

Characterization of energy metabolism and blood flow distribution in myocardial ischemia in hemorrhagic shock

To characterize the mechanisms for myocardial ischemia induced by hemorrhagic shock, 29 dogs were subjected to hemorrhage at a mean aortic pressure (MAoP) of 30-60 mmHg. After 10 min of hemorrhage, the beating hearts were rapidly cross sectioned and freeze clamped to visualize the two-dimensional distribution of myocardial ischemia with NADH fluorescence (NADH-F) in 22 dogs. NADH-F was developed at an MAoP of 40 mmHg or less and involved both the subendocardial half and the subepicardial half of the left ventricle [34 +/- 14 vs. 20 +/- 14% (P < 0.05) and 65 +/- 16 vs. 52 +/- 15% (not significant) of the cross-sectional area of the left ventricular slice at MAoP levels of 40 and 30 mmHg, respectively]. Magnified NADH-F photography demonstrated heterogeneously distributed microischemic lesions with a columnar shape (mode of short-axis length, 60-80 microns). NADH-F-guided microsamplings revealed higher NADH and lactate concentrations in a positive NADH-F area than those in a negative NADH-F area. The ratio of endocardial to epicardial blood flow was maintained at a relatively high level (1.07 +/- 0.07 and 0.88 +/- 0.07 at MAoP levels of 40 and 30 mmHg, respectively; n = 7 dogs), and the reactive hyperemia was preserved as well. In conclusion, myocardial ischemia in early hemorrhagic shock was characterized by minimal transmural heterogeneity and marked heterogeneity between contiguous small regions.

Stability of microcystins from cyanobacteria--IV. Effect of chlorination on decomposition

Microcystins, the cyclic heptapeptide toxins produced by cyanobacteria such as Microcystis, show tumor-promoting activity through inhibition of protein phosphatases 1 and 2A. They potentially threaten human health, and are increasing the world-wide interest in the health risk associated with cyanobacterial toxins. In this study, the effect of chlorination on the decomposition of microcystins-LR and -RR was examined. The toxins were easily decomposed by chlorination with sodium hypochlorite, and the decomposition depended on the free chlorine dose. In this operation, many reaction products were formed, one of which was determined to be dihydroxymicrocystin formed through the chloronium ion at the conjugated diene of Adda [3-amino-9-methoxy-10-phenyl-2,6,8-trimethyl-deca-4(E), 6(E)-dienoic acid], followed by hydrolysis. Other products may be its stereoisomers and/or regioismers. No noxious products were detected from the chlorination process of microcystin-LR. Although these results suggested that chlorination at an adequate chlorine dose is very effective for the removal of microcystin in raw water, preoxidation of the cell itself with chlorine must be avoided, because it frequently causes toxin release from algae and produce trihalomethanes during water treatment.

Analysis of creatinine, vanilmandelic acid, homovanillic acid and uric acid in urine by micellar electrokinetic chromatography

A simultaneous determination of vanilmandelic acid, homovanillic acid, creatinine and uric acid using capillary electrophoresis was investigated. The optimum conditions of buffer concentration, pH and surfactant concentration were studied, and high resolution was obtained using a 30 mM phosphate buffer (pH 7.0) containing 150 mM sodium dodecyl sulfate. The detection was by UV absorbance at 245 nm and the column was a fused-silica capillary of 67 cm x 75 microm I.D.. The determination of these metabolites in human urine was completed within 15 min without any interferences.

Quantitative detection of ultraviolet-specific p53 mutations in normal skin from Japanese patients

We have previously developed sensitive methods to detect UV-specific p53 mutations (CC to TT tandem mutations) and have reported that such mutations could be found in the normal skin cell populations of sun-exposed body sites, but not in those of covered sites, in Australian cancer patients. We have now further refined our allele-specific PCR method for detecting CC to TT mutations at codons 247/248 of the p53 gene to allow quantitative measurements. Using DNA containing this mutation from a tumor as a standard for calibration and 5 micrograms of genomic DNA/PCR reaction, we could detect 1 mutant allele in about 10(6) wild-type alleles. It is essential to use purified primers and 64 degrees C as the annealing temperature for PCR. Our method has been applied in a study of the correlation of sun exposure and accumulation of CC to TT mutations in normal skin biopsies from Japanese patients. There were more p53 mutations in samples taken from sites that were chronically exposed to the sun than in those from covered sites. A significant trend of increased p53 mutation frequency with increase in age of subjects was found, suggesting the cumulative nature of the mutation. On the other hand, the p53 mutation frequency was higher in patients with premalignant tumors or nonmelanocytic skin cancer than in patients with only benign tumors. These results confirm the utility of PCR-based p53 gene mutation assays for the measurement of exposure to UV as well as for predicting the risk of UV-associated skin cancer.

[Mitrofanoff procedure with bladder-sparing urethrectomy in female urethral carcinoma: report of a case]

A 60-year-old woman with urethral carcinoma treated by bladder sparing surgery is reported. A tumor of Grabstald's clinical stage C2 arose from the anterior urethra infiltrated into the distal wall of vagina with invasion of vaginal mucosa. Pathological findings revealed poorly differentiated squamous cell carcinoma. She underwent a wide local excision of the urethra and the anterior vaginal wall with preserving the bladder. An appendicovesicostomy (Mitrofanoff procedure was selected for the urinary diversion. This technique provided a small stoma, appropriate continence, normal bladder sensation and preseving renal function. Bladder-sparing urethrectomy could be an alternative treatment for female urethral tumors.

Coronary vasoconstrictive effects of neuropeptide Y and their modulation by the ATP-sensitive potassium channel in anesthetized dogs

OBJECTIVES

This study examined the coronary vasoconstrictive action of endogenous neuropeptide Y (NPY) during sympathetic nerve stimulation and its modulation by the adenosine triphosphate (ATP)-sensitive potassium (KATP) channel in vivo.

BACKGROUND

Exogenous NPY was characterized by its potent vasoconstrictive effect. However, endogenous NPY has failed to show any vasoconstrictive activity in vivo.

METHODS

We studied 70 anesthetized dogs with vagotomy under beta-adrenergic blockade. Ansae subclaviae stimulation and intracoronary administration of the neurotransmitters (NPY and norepinephrine) were done with or without alpha-adrenergic blockade, NPY antagonist BIBP3226 or KATP channel acting agents. We measured coronary vascular resistance (CVR) and the neurotransmitter levels in systemic arteries and the great cardiac vein, and the amount of overflow (venoarterial difference times myocardial blood flow).

RESULTS

During nerve stimulation, NPY levels correlated significantly with CVR at the highest r value (r = 0.850, p < 0.0001) obtained for the venous level under alpha-blockade, but norepinephrine showed no correlation. Treatment with BIBP3226 abolished the correlation between NPY level and CVR under alpha-blockade. Without alpha-blockade, norepinephrine levels correlated significantly with CVR; however, NPY showed no correlation. The amount of NPY overflow during the stimulation was nearly 1,000-fold lower than norepinephrine overflow. Exogenous NPY had a 100-fold more potent coronary vasoconstrictive action than that of norepinephrine. The KATP channel antagonist glibenclamide enhanced vasoconstriction of NPY, and the agonist pinacidil suppressed it with a predominant effect in the subepicardial region.

CONCLUSIONS

During sympathetic nerve stimulation, the vasoconstrictive actions of NPY are masked by norepinephrine under intact alpha-adrenoceptor conditions, manifest during alpha-blockade and modulated by KATP channel activity.

Co-secretion of parathyroid hormone and parathyroid-hormone-related protein via a regulated pathway in human parathyroid adenoma cells

Parathyroid-hormone-related protein (PTHrP) is widely expressed not only in malignant tumors but also in both epithelial and nonepithelial cells of normal tissues. Secreted PTHrP is suspected to act as a paracrine or autocrine regulator. However, little is known about its secretory pathway. To cast light on this question, we studied the intracytoplasmic distribution of parathyroid hormone (PTH) and PTHrP immunohistochemically and immunoelectron microscopically in 10 surgically resected parathyroid adenomas. Double immunostaining was performed using anti-PTH antibody and a newly established anti-PTHrP antibody to reveal the relationship between their two distributions. Additional examination by cell immunoblot assay was performed to determine whether both PTH and PTHrP are secreted simultaneously. Both PTH and PTHrP were actually secreted from individual parathyroid cells simultaneously on cell immunoblot assay. Immunohistochemically, there were two different types of adenoma cells, i.e., one positive only for PTH and the other positive for both PTH and PTHrP. PTH was distributed linearly or fine granularly along the cytoplasmic membrane, whereas PTHrP was distributed diffusely or coarse granularly in the cytoplasm. The intracytoplasmic distributions of PTH and PTHrP often overlapped. Immunoelectron microscopical examination demonstrated that PTHrP co-localized with PTH in the same secretory granules. The results clearly demonstrated that PTHrP can be co-secreted with PTH via a regulated pathway using secretory granules.