Tetracycline-resistance in lactose-positive enteric coliforms originating from Belgian fattening pigs: degree of resistance, multiple resistance and risk factors.

Between March and October 2003 a field study was conducted in 50 randomly selected pig herds to assess the degree of tetracycline-resistance in lactose-positive enteric coliforms (LPEC) originating from fattening pigs and to evaluate the combined effects of various husbandry conditions on the development and persistence of antimicrobial-resistant bacteria. Data on housing, management and antimicrobial-drug consumption were collected, as well as faecal samples at three production stages: end of the nursery period (mean age: 72 days), end of the grower period (mean age: 125 days) and end of the finisher period (mean age: 186 days). The degree of tetracycline-resistant LPEC was determined by means of an agar dilution method. Tetracycline-resistant LPEC were found in every herd. The overall degree of tetracycline-resistance in LPEC was 56.8% (S.D. 22.4%). Only a very weak relation was found between the degrees of TETR in the different production stages within the same herd, indicating that the degree of TETR is mainly associated with the production stage rather than with the farm as a whole. The risk factor analysis showed that besides the antimicrobial-drug use, other factors like inside pen hygiene can influence the development and maintenance of antimicrobial-resistant bacteria in the gastrointestinal tracts of pigs. It was also observed that tetracycline-resistance in commensal Escherichia coli is often linked with resistance to other antimicrobial drugs like ampicillin and trimethoprim-sulphonamides. These results illustrate that the epidemiology of antimicrobial resistance is influenced by antimicrobial-drug use, cross-resistance development and non-antimicrobial risk factors.

Fine-needle aspiration cytology of small-cell carcinoma of the parotid.

Small-cell carcinomas arise uncommonly in extrapulmonary sites and are rare primary neoplasms in the salivary glands. We report on the aspiration cytology and immunohistochemical findings of a small-cell carcinoma of the parotid gland in an 81-yr-old man.

Fine-needle aspiration cytology of pancreatoblastoma.

Pancreatoblastoma is a rare pancreatic neoplasm seen most commonly in the pediatric age group. We report on the aspiration cytology and immunohistochemical findings of a pancreatoblastoma in a 16-yr-old male.

Fine-needle aspiration cytology of lymphangioma of the parotid gland in an adult.

Lymphangioma or cystic hygroma is an uncommon benign congenital tumor of lymphatics that is seen in children and, rarely, adults. Lymphangioma primarily involving the parotid gland is an extremely uncommon occurrence in adults. We report on the cytologic findings of a parotid lymphangioma in a 34-yr-old man which showed 13 cc of yellow fluid with red blood cells, lymphocytes, and rare fragments of benign-appearing salivary gland epithelium. The differential diagnosis of cystic parotid gland lesions in adults may include Warthin's tumor, lymphoma, benign lymphoepithelial lesions, branchial cleft cysts, chronic sialadenitis, cystic low-grade mucoepidermoid carcinoma, and cystic pleomorphic adenoma. In this case, the fine-needle aspiration findings along with the magnetic resonance imaging (MRI) findings of a multiloculated cystic mass in the parotid gland allowed the diagnosis of lymphangioma.

Nephrogenic adenoma mimicking carcinoma: a potential pitfall in cytodiagnosis.

Nephrogenic adenoma of the urinary bladder and urethra is an uncommon benign lesion of the urinary epithelium that can cytologically and histologically mimic malignancy. We report on the cytologic findings of a case of nephrogenic adenoma of the urethra that mimicked malignancy in an 84-yr-old woman. The differential diagnosis of this problematic lesion is discussed, and the literature describing the cytologic features is reviewed.

Fine-needle aspiration cytology of esophageal leiomyomatosis.

Leiomyomata are the most common benign neoplasms of the esophagus, but they are still very rare in comparison to malignant tumors of this organ. We report on the aspiration cytology findings of a case of esophageal leiomyomatosis in a 19-yr-old man. Diagn. Cytopathol. 1999;21:197-199.

Fine-needle aspiration of a presacral myelolipoma: a case presentation with flow cytometry and immunohistochemical studies.

Myelolipomas are benign soft-tissue tumors predominantly found in the adrenal gland. Extra-adrenal myelolipomas are rare, with about 30 previous cases reported. Approximately half of the reported cases were located in the presacral region. These were usually found at autopsy or during the workup of vague abdominal symptoms. Histologically, these lesions show bone marrow elements, with adipose tissue and scattered lymphoid aggregates. Radiologically-guided fine-needle aspiration (FNA) is helpful in establishing the diagnosis, thus obviating resection in some patients. We report on a case of an incidental presacral myelolipoma that underwent examination by computer tomography, magnetic resonance imaging, FNA, and immunohistochemical staining. This lesion was also analyzed by flow cytometry. To our knowledge, the use of the latter technique in the characterization of such tumors has not been previously reported.

In vitro displacement of phenytoin from protein binding by nonsteroidal antiinflammatory drugs tolmetin, ibuprofen, and naproxen in normal and uremic sera.

Displacement of phenytoin (90% bound to albumin) by other highly albumin-bound drugs like salicylate has been well documented. Other widely used nonsteroidal antiinflammatory drugs like tolmetin, ibuprofen, and naproxen are also strongly bound to albumin and can potentially displace phenytoin. However, phenytoin-ibuprofen interaction has been poorly studied in the past, and interaction of phenytoin with tolmetin or naproxen has not been studied before. For normal serum pool (albumin 3.7 g/dl), we observed significant increases in free phenytoin concentrations only with antiinflammatory drug concentrations at the upper end of therapeutic or above therapeutic concentrations. However, for the uremic pool (albumin 2.9 g/dl), displacement of phenytoin was significant even at the lower end of therapeutic concentrations of those antiinflammatory drugs. Of the three antiinflammatory drugs we studied, ibuprofen caused the highest displacement of phenytoin.

Papillary renal tumors. Morphologic, cytochemical, and genotypic features.

BACKGROUND: Papillary renal tumors lack alterations of chromosome 3 and show trisomy of chromosomes 7 and 17, genotypic features distinct from nonpapillary carcinomas. METHODS: The authors examined 39 papillary renal neoplasms to identify morphologic features allowing distinction of high grade from low grade tumors. Twenty-nine papillary tumors and 13 nonpapillary tumors were examined for the presence of trisomy of chromosome 7 using fluorescence in situ hybridization. Data recorded included tumor size, stage, grade, architectural pattern, and the presence of glycogen, foam cells, and iron. RESULTS: Nineteen tumors were classified as low grade and 20 as high grade. The high grade tumors more often formed tall papillae with solid and tubular areas and had more intracellular glycogen, whereas the low grade tumors were more often trabecular. There was no significant difference in tumor size or iron deposition. High grade tumors were of higher stage. Foam cells more commonly were noted in low grade tumors. Sixty-seven percent of low grade, 43% of high grade, and none of the nonpapillary tumors showed trisomy of chromosome 7. Metastases developed only in patients with high grade papillary tumors (10/19, 7 within 2 years of diagnosis), all of whom died of disease. CONCLUSIONS: Papillary renal carcinomas with high nuclear grade are more likely to behave in an aggressive fashion, whereas those with low nuclear grade may be associated with longer disease free survival. Furthermore, trisomy of chromosome 7 can be identified by fluorescence in situ hybridization and is useful in differentiating true papillary from nonpapillary renal neoplasms.

Renal chromophobe cell carcinoma: limitations of paraffin-embedded tissue.

Chromophobe cell carcinoma of the kidney is distinguished from other renal cortical tumors by the ultrastructural presence of numerous cytoplasmic vesicles of unknown composition. Failure to detect vesicles in paraffin-embedded tissue in the archival material of 10 putative chromophobe cell tumors stimulated an investigation into the effects of fixatives and dehydrating solvents on vesicle integrity. We found that although vesicles are removed by dehydrating agents during paraffin embedding, osmium tetroxide postfixation prevents vesicle loss during dehydration for electron microscopy. We conclude that paraffin-embedded tissue is useless for histochemical studies of vesicle composition and cannot be employed for the ultrastructural confirmation of a histologic diagnosis of chromophobe cell carcinoma since the intracellular vesicles are no longer present.

AIDS awareness in North Dakota--a knowledge and attitude study of the general population.

The AIDS program of the North Dakota Department of Health and Consolidated Laboratories has provided a broad range of information concerning AIDS (acquired immunodeficiency syndrome) and HIV (human immunodeficiency virus) to State residents over the past few years. The ultimate intent of these intervention efforts was to decrease viral transmission. To assess residents' knowledge and attitudes regarding AIDS, a statewide, random telephone study was conducted by AIDS Program personnel in the fall of 1987, 1988, and 1989, with technical assistance from the Bureau of Governmental Affairs, University of North Dakota. Study results indicated a majority of the respondents considered themselves to have at least "some" knowledge about AIDS. Participants' comprehension of viral transmission routes and prevention methods increased over the 3 years, yet misconceptions still exist. Identified areas of misconception were accentuated in subsequent State educational programs. When the results were compared with national studies, knowledge levels in North Dakota were generally similar to but frequently superior to the nationwide levels.

Comparison of in vitro and in vivo models to assess venous irritation of parenteral antibiotics.

The venous irritation potential of four parenteral antibiotics, tetracycline hydrochloride (TET), erythromycin lactobionate (ERY), amphotericin B (AMP), and cephaloridine (CEP), was evaluated in an in vivo model using the rabbit ear vein. Lateral ear veins of New Zealand White rabbits were infused for 1 hr with test solutions containing TET (0.25,2.5, or 10 mg/ml), ERY (2.5, 5, or 25 mg/ml), AMP (0.05, 0.1, or 0.5 mg/ml), or CEP (4 or 20 mg/ml). Control rabbits received comparable volumes of 0.9% NaCl or 5% dextrose. Approximately 24 hr postinfusion, the rabbits were evaluated for visually evident changes in the treated ears. Pathologic evaluation of the veins was performed using histologic sections and scanning electron microscopy. TET, ERY, and AMP caused concentration-dependent changes in veins characterized primarily by loss of endothelium with associated inflammation and thrombus formation, consistent with the known clinical irritancy of these antibiotics. CEP, on the other hand, was well tolerated in the rabbit ear vein, paralleling its low irritancy potential in man. Test solutions identical to those used in vivo in rabbits were also evaluated in established in vitro assays for hemolytic potential when mixed with whole blood from monkeys and for damage to L6 muscle cells as determined by loss of creatine phosphokinase. Results of the in vitro test systems paralleled those of the rabbit ear model, with TET, ERY, and AMP exhibiting dose-dependent hemolysis and muscle cell toxicity, while CEP was comparatively nontoxic. Of the three models, the rabbit ear vein had the greatest sensitivity when histopathologic evaluation was employed.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of immediate blood flow enhancement on the postischemic kidney: functional, morphologic, and biochemical assessments.

Our purpose was to assess the influence of blood flow enhancement to the immediate postischemic kidney on tubular cell energetics and on the severity of the resulting ischemic acute renal failure (IARF). Female Sprague-Dawley rats were subjected to 40 minutes of bilateral renal artery occlusion (RAO). Half of the rats received a 5% body weight infusion of iso-oncotic saline solution (IOS; over 50 minutes) to acutely increase renal blood flow (RBF) immediately after vascular clamp release. The remaining half of the rats served as controls. The short-term effects (0 to 1 hour after vascular reflow) of IOS infusion on RBF, clearance iothalamate sodium (Cioth), urine Na excretion (UNaE), urine flow rate, tubular metabolic work (renal oxygen consumption, Qo2), adenine nucleotide concentrations, and renal histologic findings were assessed. The severity of the IARF (Cioth histologic findings) was also compared between the IOS-treated and the control groups 24 hours later. Postischemic (0 to 1 hour) RBF in control IARF rats and IOS-treated IARF rats was 2.3 +/- 0.3 and 13.6 +/- 0.4 ml/min, respectively (P less than 0.01) (normal RBF 6.1 +/- 0.4 ml/min). At 0 to 1 hour after reflow IOS-treated IARF rats had significantly higher Cioth (13 X), UNaE (18 X), urine flow (18 X), and Qo2 (4 X) than the control IARF group. Despite the fourfold increase in aerobic tubular work induced by IOS infusion, renal adenosine triphosphate (ATP) content did not decrease. At 24 hours after vascular reflow the severity of IARF was the same in the control and IOS-treated groups.(ABSTRACT TRUNCATED AT 250 WORDS)