Isolation and molecular biological investigations of avian poxviruses from chickens, a turkey, and a pigeon in Croatia.

In the last 3 yr, several outbreaks of avian poxviruses (APVs) have been observed in different parts of Croatia. Four strains of APVs, from chickens, a pigeon, and a turkey, were isolated from cutaneous lesions by inoculation onto the chorioallantoic membranes (CAM) of 12-day-old specific-pathogen-free chicken embryos. The resulting proliferative CAM lesions contained eosinophilic cytoplasmic inclusion bodies. The characteristic viral particles of poxvirus were detected in the infected CAM and also in the infected tissues by transmission electron microscopy. Further identification and differentiation of the four various APVs were carried out by the use of a polymerase chain reaction (PCR) combined with restriction enzyme analysis. Using one primer set, which framed a region within the APV 4b core protein gene, it was possible to detect APV-specific DNA from all four tested isolates. PCR results revealed no recognizable differences in size of amplified fragments between the different APVs from chickens, turkey, and pigeon. Restriction enzyme analysis of PCR products using NlaIII showed the same cleavage pattern for turkey and chicken isolates and a different one for the pigeon isolate. Multiplex PCR for direct detection of APV and reticuloendotheliosis virus (REV) was carried out to determine the possible integration of REV in the genome of isolated APVs. The obtained results revealed that REV was present in chicken and turkey strains of poxviruses, whereas the pigeon isolate was negative. It is not known whether the avipoxvirus vaccine strain used in Croatia is contaminated with REV or if the REV is naturally contaminating Croatian field strains of fowl poxvirus. The latter is indicated by the negative REV finding in the pigeon, which was not vaccinated. The results of the present study indicate the reemergence of fowlpox in Croatia, where infections have not been recorded since 1963 and never confirmed etiologically.

Gizzerosine-induced histopathological lesions in broiler chicks.

1. The aim of this study was to investigate pathomorphological changes in broiler chicks fed with different doses of gizzerosine, a substance produced during the heat treatments of fish meal. 2. The experiment was carried out in Ross broiler chicks which were divided into three groups: group A received 100% of non-medicated commercial mash for broiler chicks. During an experimental 5-d period, 50% of commercial mash was replaced with unheated fish meal (0.65 ppm gizzerosine) in group B and in group C with heated fish meal (1.15 ppm gizzerosine). Fourteen chicks from each group were killed every day. Samples of gastrointestinal and lymphoid organs, lung, pancreas, liver, brain and kidney tissue were sampled for histopathological analysis. Organs were embedded in paraffin and stained with hematoxylin-eosin stain and using periodic acid-Schiff reagent (PAS) and Sudan III (frozen sections). 3. Necropsy did not reveal notable differences between treated groups. There were no significant histopathological changes in immunocompetent organs nor in the lungs, the pancreas, the kidney or the brain. Sharply demarcated multiple vacuoles were observed in the myocardium in group C toward the end of the experiment. In group C, the prevalent changes in the gizzard and the proventriculus were slight to severe cuticle erosions and oedema of the lamina propria with or without multiple vacuoles, respectively, towards the end of the experiment. The most prominent changes toward the end of the experiment were dispersed cell vacuolisation in duodenal, jejunual, ileal and caecal lamina propria in group C. 4. In conclusion, it should be emphasised that extra-gizzard gizzerosine-induced lesions are probably not mediated by H2-receptor stimulation, but could be a consequence of cellular hypoxia.

Disorders of male rat reproductive tract under the influence of atrazine.

The effects of atrazine exposure on testicular sperm number, epididymal sperm number and motility and alpha-glucosidase activity in the epididymis were studied in Fischer rats. Histological changes in the testicular tissue were followed by light and electron microscopy. Groups of adult animals were treated i.p. with 60 and 120 mg atrazine kg(-1) body wt. twice a week over 60 days. The results indicate a decrease in the body weight and relative weights of pituitary and ventral prostate vs control, measured on the last day of treatment in both treated groups. Testicular sperm number (expressed as number of sperm per 500 Sertoli cells) in atrazine-treated groups increased with the treatment time due to the reduced sperm motility. Therefore atrazine treatment provoked a significant decrease in sperm number and motility in epididymis, measured after the last day of treatment. alpha-Glucosidase activity in the epididymis, after the last day of treatment, showed a decrease in both treated groups vs control values. Histological analysis of testicular tissue from treated rats showed the cell disorganization and cell clusters together with spermatocytes. Electron microscopy presented differently vacuolated cytoplasm, collagen fibre was reduced, Leydig cells were of irregular shape with unequal form and cisternae of rough endoplasmic reticulum were accentuated and softly widened. In Sertoli cell cytoplasm, atrazine treatment provoked degenerative changes. According to the results obtained, it is evident that atrazine exerted morphological changes and a toxic effect on sperm and their motility.

A case of metastasizing ovarian granulosa cell tumour in the myocardium of a bitch.

Clinical examinations including X-ray analysis, gross pathological, histopathological and ultrastructural investigations were performed on a case of ovarian granulosa cell tumour in a 5-year-old German boxer bitch. Radiographic examination of the abdomen revealed a round, sharply demarcated formation about 4-5 cm in size. The tumour of the left ovary was of a malignant granulosa cell type, with numerous metastases 5-20 mm in size, present in the myocardium (left ventricle), lungs (in all lobes) and prescapular lymph node. Ultrastructural characterization of the tumour demonstrated closely packed cells, with rough endoplasmic reticulum, indicating markedly enhanced protein synthesis probably associated with rapid cell proliferation.

[Oncocytic lesions of the larynx]. / Onkocitna lezija grkljana.

Oncocytic lesions of the larynx are considered particularly rare. Different names for these lesions have been used as a result of various theories concerning their biologic nature which is still controversial. Most investigators interpret these lesions as oncocytic metaplasias of the mucous gland cells in the larynx connected with senile involution of the upper respiratory tract with or without hyperplasia rather than true neoplasias. They are benign lesions, comprising 0.5 to 1% of all laryngeal mucosal changes, with a tendency to multifocal involvement occurring in patients over 50 years of age. Surgical excision is the treatment of choice. A case is reported.

Aspiration cytology of renal-cell carcinoma metastatic to the thyroid.

Fine needle aspiration (FNA) of a thyroid mass clinically suspected of being acute thyroiditis led to a cytologic diagnosis of hypernephroma metastatic to the thyroid and to the subsequent detection of the occult primary tumor. The FNA cytomorphologic findings were substantiated by cytochemical staining of FNA samples and confirmed by subsequent histopathologic examination of the resected thyroid. Postoperative studies revealed an expansive growth in the left kidney; analysis of the nephrectomy specimen showed an invasive renal-cell carcinoma. This case emphasizes the considerable value of FNA biopsy in making the frequently difficult preoperative differential diagnosis of primary and metastatic thyroid tumor and the importance of cytochemical analyses in making that distinction and in suggesting the site of the primary tumor.

[Juvenile papillomatosis of the larynx]. / Juvenilna papilomatoza larinksa.

Juvenile laryngeal papilloma is the most common childhood neoplasm of the larynx. It is most often multiple and is characterized by a strong tendency to recur. Seventy-eight children with primary juvenile laryngeal papillomatosis (JLP) were treated at the ENT Department of the Zagreb University School of Medicine in the last 20 years and in the last 6 years interferon has been introduced into the therapy. Causes of the recurrence and the resistance to the therapy have been investigated. It has been shown that the administration of interferon has a certain effect on the tumor growth, but it has no effect against tumor recurrence. In patients with a severe clinical course the epithelial atypia of basal layer of papilloma and the increased enzymatic activity have been found.

The pharmacology of reversible monoamine oxidase inhibitors.

The older monoamine oxidase inhibitors (MAOIs) are mechanism-based, irreversible inhibitors of MAO; most inhibit both the A and B forms of MAO. Several of the drugs are hydrazine derivatives which have non-specific effects other than MAO inhibition. These properties convey disadvantages, which may be seen as serious, though infrequent, adverse events--the 'cheese effect', hepatotoxicity, amphetamine-like activity, orthostatic hypotension and anticholinergic effects. New, reversible MAOIs stem from a variety of chemical classes and are more specific in their effects, with relatively rapid onset of action, direct relationship between plasma concentration and pharmacological effect, and no prolonged carry-over phenomena.

[Changes in the skin in transplantation versus host reaction. 2. Our clinical findings from observations using light microscopy and electron microscopy]. / Promjene u kozi uslijed reakcije transplantata protiv primaoca. 2. Vlastita klinicka opazanja te svjetlosnomikroskopski i elektronskomikroskopski nalazi.

A clinical, light microscope and electron microscope study of skin changes was undertaken in 19 patients after bone marrow transplantation. Thirteen of the total number of 19 patients were clinically suspect of the acute and 6 of the chronic form of GvHD. Skin biopsy between the seventh and thirtieth day following transplantation confirmed the diagnosis of the acute form of GvHD in 7 of the 19 patients. In 4 of the 6 patients in whom skin biopsy did not verify the diagnosis of the acute form of GvHD, completely atypical rash in addition to signs of GvHD of the liver and intestines developed between the 30th and 50th day following transplantation. In all 6 patients who were clinically suspect of the chronic form of GvHD, skin biopsy performed some 4-10 months after transplantation confirmed the diagnosis of chronic, sclerodermoid or lichenoid GvHD. Furthermore in 71% of the patients with histologically verified chronic form of skin GvHD, symptoms of liver and intestine GvHD were present too at the time of the skin biopsy. With regard to the fact that histologically the least reliable seems to be the diagnosis of Grade 1 cutaneous GvHD, the authors recommend that regular dermatological follow-up examinations be made in the period of 7 to 50 days following transplantation in addition to skin biopsy in the case of appearance of any rash. Electron microscopy revealed in both forms of GvHD, the acute and the chronic, the most significant epidermal changes, i.e. degeneration of the cellular organelles and the appearance of numerous intracytoplasmic vacuoles.

Investigations in exaggerated juvenile laryngeal papillomas.

In the period between 1983 and 1986, 11 cases of juvenile laryngeal papillomas (JLP) were treated because of recurrences which were removed many times. One special group of 4 cases was isolated from these 11 cases in which papillomas grew very rapidly and were resistant to all management. Histological, biochemical and immunological investigations were made and the data are given.

Antidepressant drug therapy: associated risks.

Aspects of risks associated with treatment with three classes of antidepressants: tricyclic (TCA), second generation ("new") antidepressants and monoamine oxidase inhibitor (MAOI), are discussed. Moclobemide, a benzamide derivative, is a new MAOI antidepressant with reversible and preferential inhibition of the A-form of monoamine oxidase. Moclobemide is free of liver toxicity and the risk of a pressor response with tyramine-containing food is so low that strict diet restrictions are unnecessary. That MAOIs have a low incidence of side effects, particularly so called anticholinergic side effects is also true for moclobemide. A serious risk with antidepressant drugs is that the patient will use them to attempt suicide. Therefore important aspects of antidepressants are that they should take effect rapidly and be safe in overdose. No deaths from overdose have been observed with toloxatone, the only reversible MAOI antidepressant on the market to date. It is concluded that the new reversible MAOI antidepressant moclobemide is similar to other antidepressants in terms of efficacy but very noticeably superior in terms of tolerance and safety.

Oncocytomas of the kidney.

Seven cases of oncocytoma of the kidney are reported. In three patients this was the original histological diagnosis; the other four were diagnosed after a review of 165 renal tumours which had been previously diagnosed as carcinoma. The oncocytomas were also analysed by electron microscopy. In one case adenomas of the suprarenal glands were also found.