A genetic model of substrate deprivation therapy for a glycosphingolipid storage disorder

Inherited defects in the degradation of glycosphingolipids (GSLs) cause a group of severe diseases known as GSL storage disorders. There are currently no effective treatments for the majority of these disorders. We have explored a new treatment paradigm, substrate deprivation therapy, by constructing a genetic model in mice. Sandhoff's disease mice, which abnormally accumulate GSLs, were bred with mice that were blocked in their synthesis of GSLs. The mice with simultaneous defects in GSL synthesis and degradation no longer accumulated GSLs, had improved neurologic function, and had a much longer life span. However, these mice eventually developed a late-onset neurologic disease because of accumulation of another class of substrate, oligosaccharides. The results support the validity of the substrate deprivation therapy and also highlight some limitations.

Pathogenesis of Babesia caballi infection in experimental horses

The present study was designed to investigate the role of cytokines in the pathogenesis of Babesia caballi in experimentally infected horses. The expression of cytokine mRNA was determined by using reverse transcription-polymerase chain reaction in two B. caballi-infected horses for 2 weeks after the infection. In one horse, there was up-regulation of interferon-gamma, tumor necrosis factor-alpha (TNF-alpha) and interleukin-2 mRNAs, while in the second horse, expression of only TNF-alpha mRNA was up-regulated. No change was observed in interleukin-4 mRNA in both of the horses. To know the relation between nitric oxide (NO) production and pathogenesis, NO production was assayed in three dexamethasone treated-B. caballi-infected horses. Production of NO in all 3 horses increased significantly before death, although the parasitemia level remained very low. Treatment with NO inhibitor resulted in the suppression of NO production and increased parasitemia level in a horse, which died of the infection. The pathological examination showed that the main cause of the death was dyspnoea and pulmonary edema. Histopathologically, diffuse global mesangial proliferative glomerulonephritis was also observed. These results suggested that NO may be a critical effector molecule of immune defense against parasite. TNF-alpha and NO might be contributing to the pathogenesis in B. caballi infection.

Accelerated loss of islet beta cells in sucrose-fed Goto-Kakizaki rats, a genetic model of non-insulin-dependent diabetes mellitus

The Goto-Kakizaki (GK) rat is a spontaneously diabetic animal model of non-insulin-dependent diabetes mellitus, which is characterized by progressive loss of beta cells in the pancreatic islets with fibrosis. In the present study, we examined the effects of sucrose feeding on the islet pathology in this model. Six-week-old GK rats were fed with 30% sucrose for 6 weeks to induce severe hyperglycemia, and their condition was compared with that of nontreated rats. Age-matched normal Wistar rats were also given sucrose for the same periods and used for comparison. The sucrose-treated GK rats showed elevated blood glucose levels on oral glucose tolerance tests at 60 minutes and 120 minutes, representing 123% and 127% of values in untreated GK rats, respectively. At the end of the study, the mean beta-cell volume density in GK rats was 50% less than that in untreated Wistar rats. Sucrose feeding further reduced the volume densities of beta cells to only 50% of the levels of age-matched GK rats. Apoptotic cells were found in islet beta cells only in GK rats fed sucrose (mean 0.067%). There appeared to be more islets that immunohistochemically stained strongly positive with 8-hydroxy-deoxyguanosine as a marker of oxidative damage of DNA in GK rats fed sucrose compared with those not given sucrose. GK rats not fed sucrose showed significantly lower proliferative activity of beta cells measured by 5-bromo-2'-deoxyuridine uptake and intensified expression of Bcl-2 immunoreactivities at 6 weeks of age compared with those in age-matched Wistar rats. These two indices were reduced in both GK and Wistar rats with increasing age and were not affected by sucrose feeding in either group. The present study thus indicated that sucrose feeding promoted the apoptosis of beta cells in GK rats through increased oxidative stress without altering their proliferative activity.

Isolation of Streptococcus equi subsp. equi from thoroughbred horses in a racehorse-breeding area of Japan

For determination whether strangles has invaded the Hidaka district of Hokkaido, the main racehorse-breeding area of Japan, a epizootiological survey with bacterial isolation was carried out during the breeding season in 1995. Streptococcus equi subsp. equi, which is the causative agent of strangles, was isolated from two Thoroughbred horses with submandibular lymphadenitis. Isolates were identified by serological grouping, biochemical tests and analysis of cell surface proteins by Western immunoblotting. Through this survey, it revealed that S. equi subsp. equi has invaded the Hidaka district and that strangles has become prevalent in racehorse-breeding farms in this area.

Venereal infection of mares by equine arteritis virus and use of killed vaccine against the infection

Venereal infection with equine arteritis virus (EAV) was established in each of seven mares by inoculation via the cervix with 20 ml of viral suspension (> or = 8 x 10(6) plaque-forming units; PFU), following treatment with prostaglandin and oestradiol. A dose of < or = 8 x 10(5) PFU produced infection in only five of eight mares. Serum neutralizing antibody developed in mares manifesting clinical signs of equine viral arteritis (EVA), and a weak antibody was detectable in one apparently healthy mare inoculated with 8 x 10(5) PFU. Virus isolation was demonstrated not only in the buffy coat but also in nasal swabs of infected mares. EAV was isolated frequently from the body tissues of the mares (killed 10 to 34 days post-inoculation) up to day 12, but rarely from the reproductive tissues later than day 12. The virus persisted longest in the splenic and deep inguinal lymph nodes, followed by the spleen and internal iliac lymph nodes. Four mares immunized with a killed vaccine for EVA showed no clinical disease after venereal challenge with EAV; the virus was recovered from the buffy coat of three mares and from the nasal swab of one of them, but not from the remaining animal.

Secretory meningioma with severe perifocal edema--case report

An 82-year-old male presented with a small parasagittal meningioma associated with disproportionately severe perifocal edema. Histological examination including immunohistochemical staining and electron microscopy resulted in a diagnosis of secretory meningioma. In addition to tumor size, the edema could not be explained by location, growth rate, vascular involvement, or other factors. We conclude that secretory meningiomas may possess an innate ability to cause brain edema.

Emergence of rifampin-resistant Rhodococcus equi in an infected foal

To investigate the emergence of rifampin resistance in Rhodococcus equi strains isolated from foals and their environment in Japan, we compared the in vitro antimicrobial susceptibilities to rifampin of 640 isolates from 64 infected foals and 98 soil isolates from their horse-breeding farms. As a control, 39 human isolates from patients with and without AIDS were also tested for susceptibility to rifampin. All of the isolates showed rifampin sensitivity, except isolates from one infected foal and two patients with AIDS that showed rifampin resistance. To investigate the emergence of rifampin-resistant R. equi in the infected foal, which had received rifampin monotherapy for a month before euthanasia, 99 isolates of R. equi from the lesions and 20 isolates from the intestinal contents of the one foal with rifampin-resistant organisms were analyzed for rifampin susceptibilities, pathogenicities, and ribotypes. Of the 99 isolates from the lesions, all of which were virulent R. equi strains containing a virulence plasmid with a size of 85 or 90 kb, 90 (91%) isolates were rifampin resistant (MIC, > or = 12.5 microg/ml). On the other hand, of the 20 isolates from the intestinal contents, 11 (55%) isolates showed rifampin resistance (MIC, > or = 25 microg/ml), and 5 of them were avirulent R. equi strains. Among these 101 rifampin-resistant R. equi isolates with and without virulence plasmids characterized by ribotyping, 58 were type I, 20 were type II, 11 were type III, and 12 were type IV. These results demonstrated that at least eight different rifampin-resistant R. equi strains emerged concurrently and respectively from the different lesions and intestinal contents of the infected foal.

Pathogenicity and virulence of Rhodococcus equi in foals following intratracheal challenge

Twelve foals, between 27 and 83 days old, were infected with 2 strains of Rhodococcus equi by intratracheal administration. Ten of the 12 foals were inoculated with 10(4)-10(10) colony forming units (cfu) of ATCC 33701 strain. The other 2 foals were inoculated with 10(9) cfu of a plasmid-cured derivative of the ATCC 33701 strain (ATCC 33701P-). All of the 10 foals challenged with the ATCC 33701 strain showed clinical signs of pulmonary disease within 5-13 days, such as gross lesions associated with acute bronchopneumonia and microscopic lesions associated with granulomatous pneumonia. The two foals challenged with the ATCC 33701P- strain showed neither clinical signs of disease nor gross lesions. Apparently, when lacking plasmid, the virulent Rhodococcus equi lost its pathogenicity.

Comparison of tracheal aspiration with other tests for diagnosis of Rhodococcus equi pneumonia in foals

The diagnostic value of tracheal aspiration was evaluated through comparison with other diagnostic methods using an experimental model of Rhodococcus equi (R. equi) pneumonia in foals. Pneumonia was induced by spraying of the virulent R. equi strain ATCC 33701 into the trachea of foals. All foals developed fever from 11 to 16 days after bacterial inoculation. One foal was euthanized on day 26 due to its poor prognosis, and other foals euthanized on day 43. During the experiment, some tests for diagnosis of Rhodococcus equi pneumonia such as tracheal aspiration, radiography, serodiagnosis and fecal culture were carried out. R. equi was continually isolated from tracheal aspirates collected via a silicone catheter inserted transnasally on day 8 to day 32 after bacterial inoculation. On the other hand, radiography, serodiagnosis and fecal culture were demonstrated to be valuable diagnostic methods, but to be limited compared with tracheal aspiration. Indirect fluorescent antibody technique (IFA) using a monoclonal antibody against the 15- to 17-kDa virulence-associated antigens (VapA) of R. equi and PCR targeting the structural gene of VapA detected bacteria in tracheal aspirates less sensitively than the isolation technique although they were more rapid. Therefore, we conclude that a combination of tracheal aspiration and bacterial isolation was the most valuable method for routine diagnosis of R. equi pneumonia in foals.

Suppressive effect of tetraprenylacetone on gastric atrophy induced by short-term administration of N-methyl-N'-nitro-N-nitrosoguanidine in rats

BACKGROUND

Several studies have been reported on the effects of various therapeutic agents in enhancing or suppressing the carcinogenic activity of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). However, it is still unknown whether a mucosal protective agent could suppress its carcinogenic activity.

METHODS

Twenty-five Wistar male rats were divided into four groups: group 1, MNNG alone; group 2, MNNG + tetraprenylacetone; group 3, control; group 4, tetraprenlacetone alone. MNNG 100 mg/mL, was freely given to groups 1 and 2, and tetraprenylacetone (200 mg/kg intraperitoneal) was additionally administered every other day to the rats in groups 2 and 4. The animals were sacrificed at 10 weeks and the gastric mucosa examined.

RESULTS

Atrophic changes were observed in the antrum after 8 weeks of oral administration of MNNG. Furthermore, using immunohistological analysis with 5-bromo-2'-deoxyuridine (BrdU), the proliferative zone was found to be enlarged and shifted upward, although the BrdU labelling index of the proliferative zone was unaltered. Intraperitoneal administration of tetraprenylacetone every other day suppressed the MNNG-induced atrophic change and the alterations proliferative markers. Tetraprenylacetone alone did not have an effect either on morphological or proliferative markers.

CONCLUSION

These observations suggest that gastric mucosal defensive factors may play critical roles in suppressing atrophic change inducing carcinogenesis by an exogenic carcinogen.

Effects of cilostazol on the peripheral nerve function and structure in STZ-induced diabetic rats

We examined the effect of cilostazol (CZ), antiplatelet agent and potent vasoactive compound, which has an inhibitory effect on tissue phosphodiesterase, on peripheral nerve in streptozotocin-induced diabetic rats. Diabetic rats were fed for 12 weeks with a chow containing 0.01% or 0.03% CZ (w/w) and the results were compared with untreated diabetic rats. The 0.03% CZ treatment significantly improved motor nerve-conduction velocity and restored nerve Na+, K(+)-ATPase activity in diabetic rats without affecting body weight and glycated hemoglobin levels, but the effects of 0.01% CZ treatment did not reach statistical difference. Elevated sorbitol and reduced myo-inositol levels in diabetic nerve tissues were not influenced by CZ treatment. Structural analysis of the sural nerve demonstrated a partial but significant effect on decreased mean myelinated fiber area and atrophic changes of the axon in diabetic rats treated with 0.01% CZ. CZ treatment inhibited reduction of pericyte area of endoneurial microvessels in diabetic rats. Expansion of endoneurial microvessels and luminal area in relation to vascular area also tended to be inhibited by CZ treatment. Thus CZ treatment ameliorated, although not completely, functional and structural abnormalities in peripheral nerve of diabetic rats without effecting the polyol pathway. These results support the contention that vascular factors may play an important role in the etiology of experimental diabetic neuropathy and suggest that CZ may have a beneficial therapeutic effect on diabetic neuropathy.

Metastatic cancer involving pancreatic duct epithelium and its mimicry of primary pancreatic cancer

We investigated 47 autopsy cases of metastatic cancer involving the pancreas. Metastatic disease in nine cases involved the pancreatic duct epithelium. In two cases, metastatic cancer cells showed Pagetoid features. In three cases, pancreatic metastatic disease showed solitary proliferation with focal in situ carcinoma-like lesions mimicking primary pancreatic cancers. Each of these three cases had primary lung adenocarcinomas. Serial sections revealed abrupt borders between the in situ carcinoma-like lesions and the non-cancerous epithelium. Primary pancreatic cancers did not show Pagetoid features or abrupt borders between the cancerous and non-cancerous epithelium. We conclude that the possible diagnosis of pancreatic metastasis should be carefully ruled out in the histological detection of latent primary pancreatic cancer.

Gastric stump carcinosarcoma with rhabdomyosarcomatous differentiation

Gastric carcinosarcoma is an unusual tumor and its occurrence in the gastric stump is extremely rare. A report is presented here of a unique case of gastric stump carcinosarcoma with rhabdomyosarcomatous differentiation in a 74-year-old man. The patient had undergone partial gastrectomy with gastrojejunostomy (Billroth II method) 30 years previously. The tumor had both adenocarcinoma and sarcoma components, and an immunohistochemical study suggested a focal transition between these components. The main sarcomatous components showed fibrosarcomatous features with a scattered distribution of rounded tumor cells, whose rhabdomyosarcomatous differentiation was immunohistochemically determined. Ultrastructural examination supported the rhabdomyosarcomatous natures. Experience with the present tumor indicates that carcinosarcoma with rhabdomyosarcomatous differentiation can occur in the gastric stump and that this disease is capable of aggressive behavior.

Cellular proliferation and differentiation in rat atrophic gastric mucosa induced by N'-methyl-N'-nitro-N-nitrosoguanidine

It has been demonstrated that mucosal cell proliferation in atrophic gastritis is significantly accelerated, although the dynamics of the cell proliferation and differentiation have not been well characterized. We sequentially analyzed the markers of proliferation and differentiation of rat atrophic gastritis induced by MNNG. Immunohistochemical staining by anti-BrdU, anti-PCNA, and anti-PDGF-BB antibodies demonstrated that cell proliferation in atrophic gastritis was accelerated not only in the parenchymal tissue but also in the mesenchymal tissue. Expression of a gap junction protein (connexin 32), which is a marker for differentiation of epithelial cells, was reduced during the progression of atrophy. Some apoptotic cells were observed in the lower to middle third of the atrophic mucosa, whereas apoptotic cells were rarely seen in normal mucosa, which suggests that apoptosis in these parts of the mucosa may be related to the occurrence of mucosal atrophy.

Can Paneth cell metaplasia in cecum indicate the presence of colorectal epithelial neoplasia?

The main purpose of the present study was to investigate the relationship between the incidence of Paneth cells in cecal mucosa and the incidence of colorectal epithelial neoplasias. Using endoscopic biopsy specimens, obtained from cecum of 375 subjects in cases of total colonoscopy, we examined the incidence of Paneth cells in the cecal mucosa. In the present study, Paneth cells were present in the human cecal mucosa (47.7%, 179/375 subjects) regardless of age. Paneth cells were found more frequently in the subjects with colorectal epithelial neoplasia (57.3%, 90/157 subjects) than in the subjects without colorectal epithelial neoplasia (40.8%, 89/218 subjects) (p<0.01, chi(2) test). Our results suggest that the incidence of Paneth cells in cecal mucosa indicate some changes in the environment with tumorigenesis of the colorectal region according to the function of Paneth cells, proposed by other investigators.

Biodegradability of oxidized poly(vinyl alcohol)

Poly(vinyl alcohol) dehydrogenase (PVADH) purified from Pseudomonas sp. 113P3 catalyzed an oxidation of poly(vinyl alcohol) (PVA) in the presence of pyrroloquinoline quinone (PQQ) to give a beta-diketone structure on PVA. Although PVADH oxidized not only enzymatically oxidized PVA but also chemically oxidized PVA, PVA-degrading microorganisms, Pseudomonas sp. 113P3 and Arthrobacter tumescens sp. 52-1 grew on the enzymatically oxidized PVA, but not on the chemically oxidized PVA. This suggests that the growth of PVA-degrading microorganisms is affected by the structure of oxidized PVA.

Histogenesis of the gastric differentiated adenocarcinoma-expression of oncogene protein products and mucin histochemistry in minute gastric cancer

Examination of the immuno-overexpression for myc, ras, c-erbB-2 and p53 and the mucin histochemistry of the gastric adenocarcinoma cells at the earlier stages were performed using 12 lesions of the well differentiated tubular adenocarcinomas, less than 1 mm in greatest dimension (G-ade-1), from the pyloric gland or the intermediate area of the surgically resected stomach. The G-ade-1 had a high frequency of expression of oncogene myc (58%) and of the cancer suppressor gene p53 (83%), while almost no expression of ras or c-erbB-2 was observed. All lesions of G-ade-1 were positive for acid mucin staining, and 8/12 lesions (67%) also for sulfomucin, in 4/12 lesions (33%) gastric native mucin was observed. The adjacent mucosa to all G-ade-1 lesions in this study showed chronic gastritis with incomplete intestinal metaplasia. These results suggested that the human gastric differentiated adenocarcinoma developed accompanying the abnormal expression of myc and p53 with reference to intestinal metaplasia, and that these carcinoma cells always had acid mucin, often the colonic native mucin as sulfomucin, and also sometimes gastric native mucin in the earlier stages.

P53 protein expression in pancreatic tumors and its relationship to clinicopathological factors and prognosis

We examined the expression of p53 protein by immunohistochemical method in a series of pancreatic tumors and evaluated its relationships to the clinicopathological factors and prognosis. The study involved 108 cases of pancreatic tumors (79 ductal carcinomas, 1 acinar cell carcinoma, 14 endocrine tumors, 6 solid cystic tumors, 8 benign ductal tumors) and 8 chronic pancreatitides. Thirty-nine cases of pancreatic ductal carcinoma (49.4%) were positive for p53 protein. Analysis of the Cox hazards model identified p53 positivity and stage at the initial operation as an independent prognostic factor. Patients with p53 positive ductal carcinomas had a greater risk of death compared to p53 negative cases (P < 0.05). There was, however, no statistically significant correlation between p53 protein expression and other clinicopathological factors. Cases of stage III and IVb with positive p53 showed a bleak prognosis compared to p53 negative cases (P < 0.05). Our results suggest that p53 expression is common in invasive pancreatic ductal carcinomas and may have a prognostic value.

A dislocated and enlarged proliferative zone in human gastric intestinal metaplasia

There are many published reports suggesting a close relationship between intestinal metaplasia and gastric carcinogenesis, but there are few studies that examine the cellular kinetics of these tissues in humans. Thus, we sought to characterize the proliferative zone of intestinal metaplasia of the human stomach and correlate this with its known malignant potential. We examined the incorporation of bromodeoxyuridine into 228 human endoscopic biopsy specimens from duodenal mucosa (n=35) and non-intestinalized antral mucosa (n=127) as well as antral mucosa with intestinal metaplasia (n = 66). The proliferative zone in specimens with intestinal metaplasia was deeper when compared to non-intestinalized antral mucosa, but was more superficial than that of duodenal mucosa. Although the labeling index of intestinalized mucosa was similar to that of non-intestinalized antral mucosa, the size of the proliferative zone was significantly increased in intestinal metaplasia. The dislocation of the proliferative zone with an increase in its size in intestinal metaplasia is considered to be a hallmark of gastric intestinal metaplasia.

Histopathological and immunofluorescent studies on transplacental infection in experimentally induced abortion by equine arteritis virus

Five pregnant mares, at between 6 and 8 months gestation, were experimentally infected with the Bucyrus strain of equine arteritis virus (EAV). Of the five mares, four aborted and one died. The pathogenesis of the abortions was studied, using histopathologic techniques, tissue immunofluorescence and virus isolation. Common microscopic lesions in the maternal reproductive organs indicated myometritis with a degeneration of the myocytes and an infiltration of the mononuclear cells. Epithelial cells of the endometrial gland showed sporadic degeneration. Lesions in the fetal tissue included an atrophy of the lymphoid follicles in the spleen and lymph nodes with degenerated lymphocytes. The placentae were oedematous and degenerated fibroblasts were observed in the subvillous layers. Immunofluorescence detected EAV antigen in the myometrium and the endometrial gland in the dams, in the subvillous layer of the placentae, and in the aborted fetuses. EAV was recovered from the maternal uteri, placentae and fetuses. The placentae yielded the greatest amounts of the virus. Transplacental infection of the fetus was clearly demonstrated in the EAV infection.

Inhibition of development of peripheral neuropathy in streptozotocin-induced diabetic rats with N-acetylcysteine

N-acetylcysteine (NAC) is a precursor of glutathione (GSH) synthesis, a free radical scavenger and an inhibitor of tumour necrosis factor alpha (TNF). Because these functions might be beneficial in diabetic complications, in this study we examined whether NAC inhibits peripheral neuropathy. Motor nerve conduction velocity (MNCV) was significantly decreased in streptozotocin-induced-diabetic Wistar rats compared to control rats. Oral administration of NAC reduced the decline of MNCV in diabetic rats. Structural analysis of the sural nerve disclosed significant reduction of fibres undergoing myelin wrinkling and inhibition of myelinated fibre atrophy in NAC-treated diabetic rats. NAC treatment had no effect on blood glucose levels or on the nerve glucose, sorbitol and cAMP contents, whereas it corrected the decreased GSH levels in erythrocytes, the increased lipid peroxide levels in plasma and the increased lipopolysaccharide-induced TNF activity in sera of diabetic rats. Thus, NAC inhibited the development of functional and structural abnormalities of the peripheral nerve in streptozotocin-induced diabetic rats.

[A case of advanced gastric cancer remarkably responding to preoperative UFT-E therapy]

We here reported a case of advanced gastric cancer remarkably responding to preoperative short-term UFT-E chemotherapy. UFT-E was orally administered preoperatively for about a month to the patient with type 2 advanced gastric cancer. After the chemotherapy the cancer was found to be remarkably decreased in size and denatured. The amount of residual cancer cells was limited by histopathological examination following the operation and diagnosed as Grade 3 based on the criteria of histological evaluation of chemotherapy for cancer. We continued to administer UFT-E postoperatively and the patient is still alive without symptoms.

Histopathological studies of superficial-type early colorectal carcinoma

BACKGROUND

Superficial-type early colorectal carcinoma (SCa) is presently not a rare finding and is very important in discussions regarding the development of large bowel cancers, although the histologic characteristics of SCa remain obscure.

METHODS

Using 54 SCa lesions (34 intramucosal adenocarcinomas (SCa-m) and 20 adenocarcinomas with invasion to the submucosa (SCa-sm)), the largest dimension of the depressed region of the lesion and the greatest dimension of the entire lesion were measured by the computed image analyzer, and the expression of p53 and ras of SCa were examined immunohistochemically.

RESULTS

The percent of depressed regions in SCa lesions measuring less than 5 mm in greatest extent was larger than in those measuring more than 6 mm, and the percent of depressed regions in SCa-sm with deeper carcinoma invasion was lower than that of SCa-sm with shallower invasion. There was a positive correlation between the depth of invasion and the maximum dimension of the carcinoma. The frequency of association with adenoma in all SCa-m was 21% and was 32% in SCa-m that were more than 6 mm in greatest extent, although all minute SCa-m lesions less than 5 mm were pure carcinomas without any adenomatous component. Positive expression of ras was noted in 41% of SCa-m and 36% of SCa-sm, respectively, while positive expression of p53 was noted in 63% of SCa-m and 88% of SCa-sm, respectively.

CONCLUSIONS

These results suggested that 70% to 80% of SCa developed via a de novo carcinoma theory and showed the depression form in the initial histologic stage and thereafter in the flat-protrusion form, while 20% to 30% of SCa arose from the preexisting flat adenoma via the adenoma-carcinoma sequence theory. The results also suggested that p53 was related to the enlargement and deeper invasion of SCa, regardless of the sequence of development of colorectal cancer.

Galactosemic neuropathy in transgenic mice for human aldose reductase

We studied the functional consequences of an enhanced polyol pathway activity, elicited with galactose feeding, on the peripheral nerve of transgenic mice expressing human aldose reductase. Nontransgenic littermate mice were used as controls. With a quantitative immunoassay, the expression level of human aldose reductase in the sciatic nerve was 791 +/- 44 ng/mg protein (mean +/- SE), about 25% of that in human sural nerve. When the transgenic mice were fed food containing 30% galactose, significant levels of galactitol accumulated in the sciatic nerve. Galactose feeding of nontransgenic littermate mice led to a 10-fold lower accumulation of galactitol. Galactose feeding for 16 weeks caused a significant and progressive decrease in motor nerve conduction velocity in transgenic mice to 80% of the level of galactose-fed littermate mice, which was not significantly different from that of galactose-free littermate mice. A morphometric analysis of sciatic nerve detected > 10% reduction of mean myelinated fiber size but no alterations of myelinated fiber density in galactose-fed transgenic mice compared with other groups. The functional and structural changes that develop in galactose-fed transgenic mice are similar to those previously reported in diabetic animals. The results of these studies suggest that transgenic mice expressing human aldose reductase may be a useful model not only for defining the role of the polyol pathway in diabetic neuropathy but also for identifying and characterizing effective inhibitors specific for human aldose reductase.

New biodegradable oligoesters for pharmaceutical application

Tartaric acid, malic acid, and glyceric acid were copolycondensed with glycolic acid at various molar ratios in feed to quickly synthesize biodegradable oligoesters. They were likely to have a moderately cross-linked structure with relatively low molecular weights and hydrophilic groups on the chains. In addition to macroscopic gels which were insoluble in any solvents, we could obtain the oligoesters which were insoluble in water but soluble in N,N-dimethylformamide. The degradation rate of the oligoesters was higher than that of lactic acid (LA) oligomers having molecular weights of a few thousands. On the contrary, their glass transition and flow temperatures were much higher than those of LA oligomers, indicating that their handling during the preparation of drug delivery dosage forms was much improved. The formulation of microspheres containing drugs from the oligoesters revealed that they were useful as biodegradable matrices having high degradation rates.

Paget sarcoma of the cervical vertebrae: an autopsy case report and review of the literature

A 69 year old Japanese woman was hospitalized for emergency treatment of sudden onset of tetraplegia and somnolence. The patient had a long history of occipital pain without definite diagnosis. After admission, the patient progressively developed generalized palsy including respiratory paralysis, and died of bronchopneumonia. Autopsy revealed osteosarcoma of the cervical vertebrae with the features of Paget's disease involving the skull and the cervical vertebrae. Paget sarcoma is rare in Japan, where Paget's disease of the bone is an uncommon condition. A review of the world literature failed to reveal any reports describing Paget sarcoma of the cervical vertebrae. The present report indicates that the development of Paget sarcoma in the upper cervical vertebrae may cause life-threatening neurologic complications.

Adenocarcinoma arising from gastric immature teratoma. Report of a case in an adult and a review of the literature

BACKGROUND

Gastric teratoma is an uncommon tumor and usually occurs in infancy or childhood. To the authors' knowledge, malignant transformation in gastric teratoma has not been reported previously.

METHODS

An 83-year-old Japanese man presented with a large polypoid gastric tumor composed of teratomatous components and invasive adenocarcinoma. Numerous blocks of this tumor were analyzed histologically and immunohistochemically.

RESULTS

Histologically, the gastric tumor consisted of teratomatous components with diverse maturation, such as fibroblastic mesenchymal cells, striated muscle cells, cartilaginous islands, neuroepithelial components, glial tissues, squamous cell nests, glandular components, and foci of adenocarcinoma infiltrating the benign gastric tissues adjacent to the tumor stalk. Metastatic foci of teratomatous components in the resected lymph nodes contained adenocarcinomatous glands. An immunohistochemical study helped confirm the differentiation in the immature components and the differential diagnosis between atypical neuroepithelial cells and the adenocarcinoma.

CONCLUSION

This study indicates that the adenocarcinoma arose from immature gastric teratoma. A review of the literature suggests that this is the oldest reported patient with gastric teratoma and to the authors' knowledge is the first report describing gastric teratoma with malignant transformation.

[Development and expression of p53 in superficial early colorectal carcinoma]

We evaluated the histopathological and immunohistochemical findings of 41 superficial early colorectal carcinomas within 20 mm in diameter and twice of normal mucosa in height for the development. These colorectal cancers were divided into intramucosal carcinoma (21 lesions) and submucosal invasive carcinoma (20 lesions), and classified into two groups: superficial elevated type (25 lesions) and superficial depressed type (16 lesions). The average maximum diameter of superficial elevated type was larger than it of superficial depressed type, furthermore the increase in tumor diameter and the pattern of the overexpression of p53 protein was correlated to the invasivity. On the other hand, we found the submucosal invasion and the overexpression of p53 protein in the smaller depressed type carcinoma. Considering the circumstances mentioned above, we recognized the different development between superficial elevated type and superficial depressed type in the superficial early colon cancer, and thought superficial depressed type was more invasive.

Phenylacetate synergizes with retinoic acid in inducing the differentiation of human neuroblastoma cells

Phenylacetate, a natural metabolite of phenylalanine which was originally described as a plant growth hormone, has recently gained attention as a possible differentiation inducer for a variety of human tumor cell types. This interest prompted us to assess the ability of sodium phenylacetate (NaPA) to promote the differentiation of human neuroblastoma cells, both alone and in combination with retinoic acid (RA), a known inducer of neuroblastoma differentiation and maturation. Using the LA-N-5 cell line, we have determined that NaPA can stimulate the differentiation of neuroblastoma cells, as evidenced by dose-dependent inhibition of cell proliferation, neurite outgrowth, increased acetylcholinesterase activity and reduction of N-myc expression. Furthermore, NaPA and RA synergized in inducing differentiation, in that combination treatment resulted in cessation of cell growth along with morphologic and biochemical changes indicative of the loss of malignant properties. We have determined that NaPA can markedly enhance mRNA levels of the nuclear RA receptor-beta (RAR beta) in LA-N-5 cells prior to morphologic or other phenotypic changes induced by this compound. This effect appeared to be distinct from the ability of NaPA to alter tumor cell lipid metabolism via inhibition of protein isoprenylation. Thus among its varied effects on LA-N-5 cells, NaPA appears to interact with the RA pathway at the nuclear level by up-regulating RAR beta expression.

Detection of equine arteritis virus (EAV) by polymerase chain reaction (PCR) and differentiation of EAV strains by restriction enzyme analysis of PCR products

A polymerase chain reaction (PCR) based assay capable of detecting and differentiating seven strains of equine arteritis virus (EAV) from around the world was developed. The primers for the PCR were chosen from the ORF6 gene encoding the unglycosylated membrane protein (M). Viral RNA from cell culture fluids infected with each of the seven EAV strains and RNA from the live vaccine, Arvac, was detected by PCR using four sets of primers. The sensitivity of detection was increased from 100 to 1,000 times by performing nested PCR enabling the detection of RNA at a level of 0.5-5 PFU. Differentiation among the virus strains and the live vaccine was achieved by cutting the PCR-amplified products from three sets of primers with six restriction endonucleases. Using this procedure it was possible to distinguish among the seven EAV strains used.

Ultrastructure and immuno-cytochemistry of BHK-21 cells infected with a modified Bucyrus strain of equine arteritis virus

Morphogenesis of a modified Bucyrus strain of equine arteritis virus (EAV) in BHK-21 cells was studied. Bacillary tubules were first detected in the cytoplasm 8 h after infection, and mature virions 79 to 122 nm in diameter, 101 nm on average, were mostly observed in the cisternae of the rough endoplasmic reticulum (RER) at 12 h or later. They had isometrical cores and morphological subunits in the outer layer. Budding occurred from the RER and the outer nuclear membrane, but not from the cell surface. Structural linkage was detected between the tubule and the virus core. Aberrant strands were occasionally demonstrated within the nucleus 12 h after infection, and immunofluorescence and immunogold labeling revealed viral antigen also in the nucleus.

Use of the serum neutralisation test for equine viral arteritis with different virus strains

Serum cross neutralisation tests were conducted with a recent American isolate (84KY-A1) and a European isolate, (Wroclaw-2) and compared with the prototype and modified viruses of the Bucyrus strain of equine arteritis virus by using virus specific immune horse sera. The modified Bucyrus strain was neutralised and showed high neutralisation titres with all the immune sera. The prototype Bucyrus strain was also substantially neutralised, followed by the 84KY-A1 strain. As a result of the tests with the modified Bucyrus strain as the antigen, 20 seropositive horses were discovered among home-bred horses which had no previous record of clinical equine viral arteritis. Heat inactivation of the sera at 62 degrees C for 30 minutes caused the disappearance of all but the most positive reactions. When the prototype Bucyrus strain was used instead of the modified virus, no positive reactions were detectable. A serological survey, using the Bucyrus strain in a microtitre neutralisation test, was conducted with 1656 horse sera collected between 1988 and 1990 in Japan. The test disclosed only eight foreign-bred horses positive to the virus; they had been imported as competition horses. No circumstantial evidence of an effect of such horses as a source of infection for horse populations free of the virus was obtained.

Incidence of Paneth cells in colorectal adenomas of Japanese descendants in Hawaii

The main purpose of the present study was to demonstrate the incidence of Paneth cells in colorectal tubular adenomas of Japanese descendants in Hawaii. Paneth cells were found in 73 of 322 adenomas (22.7%) of Japanese descendants in Hawaii. The incidence of Paneth cells in adenomas located from the caecum to the transverse colon was significantly higher than that of adenomas from the descending colon to the rectum. The same trend of a higher incidence of Paneth cells in adenomas from the caecum to the transverse colon was observed in Japanese descendants and Caucasian residents in Hawaii and in native Japanese. The incidence of Paneth cells in adenomas of Japanese descendants in Hawaii was higher than that of native Japanese, and also that of Caucasian residents was higher than that of native Japanese.

Retinoic acid up-regulates nuclear retinoic acid receptor-alpha expression in human neuroblastoma cells

Retinoic acid (RA) nuclear receptors (RARs) are thought to mediate the cellular and molecular effects of RA on a wide variety of tissues. In most cell types, RAR alpha expression remains relatively constant following exposure to RA, while that of RAR beta is rapidly induced. In this study, we show that in human neuroblastoma, a cell type exceptionally sensitive to RA-induced differentiation, RAR alpha as well as RAR beta is markedly up-regulated by RA treatment. This effect was consistent in all 5 neuroblastoma cell lines tested and was reflected in a 2- to 5-fold increase in receptor mRNA levels as assessed by Northern-blot analysis. Using LA-N-5 human neuroblastoma cells, we found that receptor up-regulation occurred in a time- and dose-dependent fashion with increases in both RAR alpha and beta mRNA detectable 1-2 hr after the addition of RA. These inductions were not abrogated by cycloheximide, indicating that protein synthesis was not required for the RA responses. Nuclear run-off experiments combined with Northern-blot analysis of RAR alpha stability directly demonstrated that the up-regulation of RAR alpha mRNA levels reflected an increased rate of transcription without changes in message half-life. These findings, showing direct activation by RA of RAR alpha gene transcription in human neuroblastoma cells, suggest differences in the overall regulation of this receptor from that found in most other RA-inducible tissue.

Development of neutralizing antibody in horses infected with Ehrlichia risticii

The role of the humoral immune response in ehrlichial infection is unknown. Development of neutralizing antibodies during a course of Ehrlichia risticii infection in a pony was examined in vitro by determining the inhibition of E. risticii infection of P388D1 cells in the presence of the sera. The pony experimentally infected with E. risticii developed significant neutralizing activity in the sera by 15 days postinfection when parasitemia started to decline. Neutralizing activity continued to rise after recovery from the disease up to 34 days postinfection at which time the experiment was terminated. In vitro neutralizing activities in the sera from 3 additional ponies infected with E. risticii were lower at 2 weeks than at 4 weeks postinfection. The sera from vaccinated/challenged ponies had comparable neutralizing activity to those of the recovered ponies at approximately 3 to 4 weeks postchallenge. Equine sera from infected or vaccinated/challenged ponies were also effective in protecting mice from E. risticii infection. These studies demonstrated the significant development of neutralizing activity in the sera of recovered or vaccinated/challenged ponies.

[Tuberculin sensitivity to purified protein derivatives from Mycobacterium other than tuberculosis (PPD-B, PPD-Y, PPD-F and PPD-C) and PPDs among patients with mycobacteriosis--cooperative study of the Research Committee for the Mycobacteriosis in Japan]

Purified protein derivatives (PPDs) prepared from M. intracellulare (PPD-B), M. kansasii (PPD-Y), M. fortuitum (PPD-F), M. chelonei subsp. abscessus (PPD-C) and M. tuberculosis (PPDs) were simultaneously used in skin tests on patients diagnosed as having tuberculosis or atypical mycobacteriosis to reveal their specificity, clinical usefulness and immunological status of the patients. The mean diameter of reaction (redness) for patients with M. tuberculosis positive sputum (TB group, n = 71; age, 20-90 yrs) was PPDs, 20.4 mm; PPD-B, 7.9 mm; PPD-Y, 11.7 mm; PPD-F, 0.8 mm; and PPD-C, 0.3 mm. For M. avium complex positive patients (MAC group, n = 100; age, 31-89 yrs), the results were PPDs, 10.9; PPD-B, 16.9 mm; PPD-Y, 10.7 mm; PPD-F, 1.6 mm; and PPD-C, 0.3 mm. The M. kansasii positive patients (K group; n = 8) showed results of PPDs, 12.6 mm; PPD-B, 10.7 mm; PPD-Y, 20.8 mm; PPD-F, 0.5 mm; PPD-C, 0.0 mm. The M. fortuitum positive patients (F group; n = 5) had measurements of PPDs, 5.8 mm; PPD-B, 4.4 mm; PPD-Y, 9.8 mm; PPD-F, 17.8 mm; and PPD-C, 16.0 mm. The patients who were previously M. tbc. positive but presently negative patients (pre. TB group; n = 50) showed the following results: PPDs, 16.6 mm; PPD-B, 7.4 mm; and PPD-Y, 10.9 mm. For the patients who were previously M. avium complex positive (previous MAC group; n = 19), the results were PPDs, 10.4 mm; PPD-B, 9.9 mm; and PPD-Y, 7.7 mm. Also considering their frequency distribution curve, with exception of the previous MAC group, the patient groups showed specificity to the PPD of the bacilli detected. The previous MAC group recorded no significant difference in response to PPDs and PPD-B. Strong cross reactions were observed between PPD-F and PPD-C, and moderate reactions between PPDs, PPD-B and PPD-Y. Cross reactions were scarce between PPDs, PPD-B or PPD-Y and PPD-F or PPD-C. Though it is difficult to distinguish cross-reaction and multiple infections, majority of the patients (72-85%) showed greatest response to the PPD that corresponds with the species of bacilli detected. In conclusion, two or more PPDs applied simultaneously can be of aid in diagnosing mycobacteriosis especially in the early stages of the disease. Also, cross-reactions between atypical mycobacteria and PPDs should be taken into consideration when diagnosing infection caused by M. tuberculosis.