Skin tumours (n=148) of epidermal or hair follicle origin were examined immunohistochemically to determine the expression of p27(Kip1)(p27), a cyclin-dependent kinase inhibitor (CDKI), and of Ki-67. In normal skin, a large number of basal cells of the epidermis and hair follicles were positive for Ki-67 and many suprabasal epithelial cells were positive for p27. Most of the hair matrix cells were positive for Ki-67 but negative for p27. Hair papillae were strongly positive for p27. Squamous cell carcinomas had a p27 positive index (PI) significantly lower than that of trichoepitheliomas (P<0.005), basal cell tumours (P<0.05) and intracutaneous cornifying epitheliomas (P<0.001). In contrast, Ki-67 PIs of squamous cell carcinomas and pilomatrixomas were significantly higher than those of trichoepitheliomas, basal cell tumours and intracutaneous cornifying epitheliomas (P<0.01 to P<0.001). No significant difference was observed between the Ki-67 PI values of squamous cell carcinomas and pilomatrixomas. The results suggested that p27 is capable of suppressing cell proliferation in the differentiation of normal canine skin. In spite of being a benign neoplasm, pilomatrixomas had a low p27 expression; this may be a reflection of the proliferative potential of the hair matrix. The expression of p27 may be a useful marker for the analysis of cell kinetics.

Animals↗

PubMedDate not supplied

Experimental infection with equine herpesvirus 9 (EHV-9) in cats.

The pathogenicity for cats of EHV-9, a new neurotropic equine herpesvirus, was assessed by intranasal inoculation with 10(6) plaque-forming units. Four cats killed 4, 5, 6 or 10 days after inoculation showed neurological signs consisting of hyper-excitability and aggressiveness, followed by tremors, occasional convulsions, and depression. Histologically, the cats showed severe encephalitis characterized by neuronal degeneration and loss, intranuclear inclusions, perivascular cuffing and gliosis in the cerebrum. A positive immunohistochemical reaction for EHV-9 antigen was seen in degenerating neuronal cells. The lesions extended from the olfactory bulb to the rhinencephalon and hippocampus. All cats had rhinitis, with or without intranuclear inclusion bodies in the nasal mucosa, and interstitial pneumonia. These findings indicate that the cat, like certain other species such as the goat, is susceptible to experimental infection with EHV-9, and may be at risk from natural infection.

Animals↗

PubMedDate not supplied

Hematocrit as a risk factor of cerebral infarction: long-term prospective population survey in a Japanese rural community.

To elucidate the relation of hematocrit (Hct) to the incidence of cerebral infarction, a prospective follow-up study of 16 years (1965-81) was performed in a general population sample of 1220 Hisayama residents aged 44 and over, of both sexes. Most of the subjects who died during the follow-up period were autopsied, the rate being 89.0%. Hct decreased with advancing age in men, but not in women. The average value for Hct was significantly lower in women than in men. According to the mean value +/- 1 SD of Hct, the subjects were grouped into 3, in each sex as follows: low (less than 35%), normal (35-45%) and high (greater than or equal to 45%) for men, and, low (less than 30%), normal (30-40%) and high (greater than or equal to 40%) for women. During the follow-up period, cerebral infarction occurred in 117 patients. The cumulative incidence of cerebral infarction in the low Hct group for men was the lowest, even after adjustments for age and blood pressure. Conversely, the incidence in the low Hct group of women was significantly higher than that in the normal Hct group and was consistently increased with time during 2-5 years of the follow-up. After the 6th year or later, however, the incidence was gradually but significantly increased in the high Hct group, compared with the normal Hct group. Since Hct levels were related with other variables such as serum total cholesterol, serum total protein, Quetelet index and prevalence of hypertension in both sexes, heavy alcohol consumption in men, and glucose intolerance in women, such variables were taken into account using Cox's proportional hazards regression model.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMedDate not supplied

Transient cerebral ischemic attacks in a Japanese community, Hisayama, Japan.

During a 20-year follow-up of 1,621 men and women aged 40 and over in Hisayama, Japan, 18 were found to have suffered transient cerebral ischemic attacks (TIAs) determined by clinical symptoms based on criteria proposed by the US Joint Committee for Stroke Facilities. The average annual incidence rate for the first TIA was 0.56 per 1,000 residents. Age and high blood pressure were strong determinants of TIAs for men. Nine of the 18 cases with TIAs (50%) subsequently developed cerebral infarction, an incidence significantly higher than that in the 1,603 subjects without TIAs (10.9%). Lacunar infarcts were most commonly found on pathologic examination of patients with TIAs who had had a subsequent stroke.

Age Factors↗

PubMedDate not supplied

Effect of phenobarbital on hepatic gap junctional intercellular communication in rats.

The effects of in vivo exposure to phenobarbital (PB) on hepatic gap junctional intercellular communication (GJIC) and connexin protein expression in Sprague-Dawley rats were examined by in vivolin vitro dye-transfer assay, immunohistochemical staining, and by Western blot analysis. PB (50 mg/kg) was administered orally once a day for up to 6 wk. The average size of the dye spread after injection of Lucifer Yellow decreased at week 1 and remained at the same level until week 6. The area and number of connexin 32 (Cx32) spots per hepatocyte in the central zone of liver lobules decreased from week 1 to week 6, but no change of Cx32 spots in the peripheral zone was observed. The average area and number of connexin 26 (Cx26) spots per hepatocytes showed no clear change through the experimental periods. The decreased level of Cx32 protein in plasma membranes was observed in the PB group. These results suggest that PB, a liver tumor-promoting agent, inhibits hepatic GJIC in vivo in rats and that aberrant Cx32 protein expression and/or localization may be responsible for this effect.

Animals↗

PubMedDate not supplied

The effect of intralesional bleomycin on canine acanthomatous epulis.

Four dogs with recurrent acanthomatous epulis (AE) were injected with bleomycin (5 mg) intralesionally once a week. In three cases, tumors were clinically indistinguishable within three-to-eight weeks. In the fourth case, the tumor disappeared after 10 weekly injections. Through the administration period of bleomycin, no adverse reactions were recognized in any case. Electron microscopic examination together with a decrease in the percentage of mitotic cells implied that bleomycin might inhibit deoxyribonucleic acid (DNA) synthesis of tumor cells.

Ameloblastoma↗

PubMedDate not supplied

Late pathological changes of Carpentier-Edwards porcine bioprostheses in the mitral position.

Eighty-nine patients received mitral valve replacement with Carpentier-Edwards porcine bioprostheses between 1975 and 1983. Eighty-three patients (93.3%) were followed up after the operation; early death (within one month of operation) occurred in 6 patients and late death in 2 patients. After the operation, 64 survivors (85.3%), who did not require reoperation, exhibited improved symptoms according to the NYHA functional class. Of the 6 patients (6.7%) who required reoperation, 5 patients underwent reoperation 50 to 85 months after the implantation. Pathologically, all the removed valves showed degeneration of collagen and elastic fibers, no host endothelialization and mild to moderate infiltration of inflammatory cells. Thrombus in the left atrium was detected in one case. Destruction of the cusps was seen in three cases and calcification of the cusps developed in three cases. In general, the Carpentier-Edwards porcine bioprosthesis provided good clinical improvement over the periods studied. However, morphological changes of the bioprosthetic valve, such as destruction collagen and elastic fiber, and inflammatory cell infiltration of the cusps, seems to occur more frequently with the passage of time. We therefore suggest that patients with this prosthesis should be followed carefully, particularly at late intervals after implantation.

Adult↗

PubMedDate not supplied

In vitro attenuation of highly virulent infectious bursal disease virus: some characteristics of attenuated strains.

Some strains of highly virulent infectious bursal disease virus (HV-IBDV) were adapted through serial passage in embryonated eggs. The embryonated egg-adapted HV-IBDV was successfully adapted to grow in chicken embryo fibroblast (CEF) cell cultures showing a cytopathic effect by preparing the CEF cells from the virus-infected embryos. The embryonated egg- and cell culture-adapted strains significantly reduced their pathogenicity to, and did not kill any, young chickens in experimental infection. The bursal lesions of the adapted strain-infected chickens were similar to those observed in classical strain-infected chickens. Cross-virus neutralization analysis showed antigenic diversity between the cell culture-adapted HV-IBDV strains and classical strains. In immunization tests, the adapted strain-immunized chickens showed good protection against the fatal infection of HV-IBDV. Especially, in case of challenge at 3 days postimmunization, the adapted strains showed effective immunogenicity. The adapted strains appear to provide a new and effective live vaccine against HV-IBDV infection.

Animals↗