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11.
Gamma interferon (IFN-gamma) has multiple immunomodulating effects and has been postulated as a possible immunopotentiating agent for the prevention or treatment of neonatal infections. This report describes the effect of rat recombinant IFN-gamma on the oxidative burst activity and CD11b expression of neonatal and adult rat polymorphonuclear leukocytes (PMNL). Oxidative burst activity was assessed by chemiluminescence and dihydrorhodamine flow cytometry. Neonatal PMNL exhibited significantly less oxidative burst activity than did adult PMNL. IFN-gamma mildly enhanced the chemiluminescence response of PMNL from both the rat pups and adults, but this effect was not statistically significant when analyzed by a multivariate model of repeated-measures analysis of variance for both chemiluminescence and dihydrorhodamine flow cytometry. CD11b expression was also not significantly enhanced by IFN-gamma.  相似文献   
12.
The development of Babesia equi in salivary glands of adult female Boophilus microplus was observed under a light microscope using semithin sections stained with toluidine blue. Engorged nymphs were obtained from splenectomized foals experimentally infected with B. equi. As adults, they were then fed on rabbits for 5 days and the salivary glands of manually collected individuals were removed at intervals of 24 h. Sporozoites were found in type III granular acini cells between the 2nd and 5th days following feeding on the rabbits. Sporoblasts and sporozoites were observed in the same or adjacent acini cells in all the glands examined. The formation of the sporozoites occurred following the multiple division of the sporoblasts through a process of radial budding from the periphery of bodies resulting from multiple fission. Sporozoites were detected in smears of adult males stained with Giemsa, between the 2nd and 5th days following feeding by the ticks. Adults of B. microplus, fed during the nymphal phase on foals with patent parasitemia, transmitted sporozoites of B. equi to a splenectomized foal. The role of B. microplus in the transmission and epidemiology of B. equi is discussed. Received: 16 June 1997 / Accepted: 2 September 1997  相似文献   
13.
In order to determine if patients with a history of previous urothelial cell carcinoma (UCC) but with current normal urinary cytology have DNA damage in urothelial cells, the single-cell gel electrophoresis (comet) assay was conducted with cells obtained by urinary bladder washings from 44 patients (28 with a history of previous UCC). Increased DNA damage was observed in cytologically "normal" urothelial cells of patients with a history of UCC when compared with referents with no similar history and after correcting the data for smoking status and age (P < 0.018). Increased DNA damage also correlated with the highest tumor grade, irrespective of time or course of the disease after clinical intervention (Kendall tau correlation, 0.37, P = 0.016). Moreover, aneuploidy, as assessed by DNA content ratio (DCR; 75th/25th percentile of total DNA fluorescence of 50 comets/patient) was unaltered by smoking status, but increased with UCC grade: 1.39 +/- 0.12 (median +/- 95% confidence interval; referents); 1.43 +/- 0.11 (Grade I UCC; P = 0.264, against referents); 1.49 +/- 0.16 (Grade II UCC; P = 0.057); 1.57 +/- 0.16 (Grade III UCC; P = 0.003). Micronucleated urothelial cells (MNC) were also scored on Giemsa-stained routine cytological smears and were found not to correlate with DNA damage or DCR. MNC frequencies were higher for patients with a history of UCC and/or smoking than referents with neither history, but there was no statistical difference between groups. Taken together, these results suggest that the normal-appearing urothelium of patients resected for UCC still harbor genetically unstable cells.  相似文献   
14.
The crucial function of macrophages in a variety of biological processes and pathologies render these cells important targets for gene therapeutic interventions. Commonly used synthetic gene delivery vectors have not been successful in transfecting these non-dividing cells. A combination strategy involving cationic liposomes to condense and carry DNA, transferrin to facilitate cellular uptake, and the pH-sensitive peptide GALA to promote endosome destabilization, resulted in significant expression of a luciferase gene. Transfection of macrophages was dependent on the degree of differentiation of the cells. The quaternary complexes of cationic liposomes, DNA, transferrin, and GALA exhibited a net negative charge, which may obviate a limitation of cationic synthetic vectors in vivo. The lack of cytotoxicity and the expected lack of immunogenicity of these complexes may render them useful for gene delivery to macrophages in vivo.  相似文献   
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Gynecomastia is a benign condition that frequently occurs in the male breast gland; however, the cytogenetic data on this entity are very limited. To our knowledge, three cases have been reported in the literature, and the only one with an abnormal karyotype had a concomitant breast carcinoma. In this study we report clonal chromosomal alterations in a gynecomastia sample without any signs of adjacent malignant tissue. The nonrandom abnormalities observed were a deletion of 12p, monosomies of chromosomes 9, 17, 19, and 20, and the presence of a marker chromosome. Most of these alterations have been previously described in the literature in other breast lesions, including benign and malignant (male and female) tumors, indicating their recurrence and nonrandomness in abnormal processes of the mammary gland.  相似文献   
19.
The authors describe the results of an application of the surgical technique called ASTRA (anterior sagittal transrectal approach) in a 16-year-old girl with recurrent urethro-vaginal fistula. The young girl had a posttraumatic urethro-vaginal fistula. It recurred after 4 operations by a direct vaginal approach before definitive correction with the ASTRA. Three years after the operation the patient has remained well with complete healing and no fistula recurrence confirmed by a voiding cystourethrogram and urodynamic and rectal manometric tests. This report suggests that ASTRA is a useful method of treating acquired or developmental anomalies of the perineal region.  相似文献   
20.
This study investigates the effects of intracerebroventricular injection of selective agonists and antagonists of tachykinin NK(3)receptor on performance of mice in the elevated plus-maze test. Mice were treated with either vehicle or 1, 10, 100 or 500 pmol of neurokinin B or senktide ([succinil-Asp(6), MePhe(8)]substance P(6-11), a natural and synthetic selective NK(3)receptor agonists, respectively. Other mice received similar doses of [Trp(7)beta-Ala(8)]NKA(4-10)or SR 142801 ((S)-N-(1-(3-(1-benzoyl-3-(3, 4-dichlorophenyl)-piperidin-3-yl)propyl)-4-phenyl-piperidin- 4-yl)-N-m ethylacetamide) tachykinin NK(3)receptor selective peptide and non-peptide antagonists, respectively. Senktide significantly increased the frequency of entries and the time spent in the open arms, which is compatible with an anxiolytic action. Neurokinin B treatment did not alter the plus-maze parameters in a significant way. Conversely, the NK(3)peptide antagonist [Trp(7)beta-Ala(8)]NKA(4-10), but not SR142801 non-peptide antagonist, showed a reverse effect, i.e. an anxiogenic profile of action, reducing the frequency and the time spent in the open arms. Co-injection of either senktide plus [Trp(7)beta-Ala(8)]NKA((4-10)), or senktide plus SR 142801, blocked the effects promoted by senktide, indicating that centrally-administered NK(3)receptor agonists and antagonists can modulate experimental anxiety.  相似文献   
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