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51.
Comparison of the chemotactic responsiveness of two fibrosarcoma subpopulations of differing malignancy. 总被引:1,自引:3,他引:1 下载免费PDF全文
F. W. Orr J. Varani J. Delikatny N. Jain P. A. Ward 《The American journal of pathology》1981,102(2):160-167
There are several points of similarity between the processes of cancer metastasis and inflammation. In both, cells circulate in the vasculature, arrest, and cross vessel walls, thereby entering the extravascular tissues. In vitro, leukocytes and some, but not all, tumor cells exhibit chemotaxis. Since the chemotactic response of leukocytes effect their transvascular migration, we propose that chemotactic responsiveness contributes to the ability of circulating tumor cells to localize in extravascular tissues. This study was done to seek a relationship between chemotactic responsiveness of tumor cells and their behavior in vivo. Two subpopulations of cells were isolated from a methylcholanthrene-induced fibrosarcoma. The two cell lines were compared with regard to their biologic behavior in vivo and their chemotactic responsiveness in vitro. In vivo one subpopulation was highly malignant. An injection of 2.0 x 10(5) cells into the footpad of syngeneic mice led to the development of primary tumors in 87% of the animals and lung metastases in 61% of the animals with primary tumors. This line demonstrated chemotaxis to a factor that behaved similarly in gel filtration and showed immunologic reactivity similar to that of a previously described tumor cell chemotactic factor derived from the fifth component of complement. In contrast, an injection of the same number of cells from the second subpopulation of fibrosarcoma cells led to the development of primary tumors in only 12% of syngeneic mice, and lung metastases did not occur. Neither this subpopulation nor normal embryonic fibroblasts demonstrated chemotactic responsiveness. We postulate that the ability of tumor cells to respond to specific chemotactic stimuli may be one of the many unique properties which distinguish malignant from benign tumor cells. This is the first report documenting the chemotactic responsiveness of non-ascites tumors and fibrosarcomas. 相似文献
52.
Ameloblastic fibroma of the jaw is a rare, benign mixed odontogenic tumor, having little tendency for local invasion and a low recurrence rate. Cytologic distinction from ameloblastoma, ameloblastic fibrosarcoma, and intraosseous adenoid cystic carcinoma is necessary, in view of the different biologic behavior. A painful, slow-growing swelling of the jaw in a 5-yr-old child clinicoradiologically considered as a benign cystic lesion was aspirated. Sheets of small monomorphic epithelial cells with peripheral palisading by columnar cells were seen on cytology smears. The striking feature was central hyaline globules in some tubules. A cytologic possibility of adenomatoid odontogenic tumor was suggested. Histopathology, however, confirmed it to be an ameloblastic fibroma. 相似文献
53.
Effects of prednisolone treatment on cytokine expression in patients with leprosy type 1 reactions 下载免费PDF全文
Andersson AK Chaduvula M Atkinson SE Khanolkar-Young S Jain S Suneetha L Suneetha S Lockwood DN 《Infection and immunity》2005,73(6):3725-3733
Leprosy type 1 reactions (T1R) are due to increased cell-mediated immunity and result in localized tissue damage. The anti-inflammatory drug prednisolone is used for treatment, but there is little good in vivo data on the molecular actions of prednisolone. We investigated the effect of prednisolone treatment on tumor necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-10, and transforming growth factor beta1 (TGF-beta1) mRNA and protein expression in blood and skin biopsies from 30 patients with T1R in India. After 1 month of prednisolone treatment the sizes of the skin granulomas were reduced, as were the grades of cells positive for TNF-alpha and IL-10 in skin lesions. Increased production of TGF-beta1 was seen in skin lesions after 6 months of prednisolone treatment. Expression of mRNA for TNF-alpha, IL-1beta, and TGF-beta1 was reduced, whereas no change in IL-10 mRNA expression was detected during treatment. The circulating cytokine profiles were similar in patients with and without T1R, and prednisolone treatment had no detectable effects on cytokine expression in the blood. The data emphasize the compartmentalization of pathology in T1R and the importance of the immune response in the skin. Clinical improvement and cytokine expression were compared. Surprisingly, patients with improved skin and nerve function and patients with nonimproved skin and nerve function had similar cytokine profiles, suggesting that clinical improvement is not directly mediated by the cytokines studied here. This in vivo well-controlled study of the immunosuppressive effects of prednisolone showed that the drug does not switch off cytokine responses effectively. 相似文献
54.
Jain JK Dutton C Harwood B Meckstroth KR Mishell DR 《Human reproduction (Oxford, England)》2002,17(6):1477-1482
BACKGROUND: Vaginal misoprostol has been shown to be an effective single agent for medical abortion. This randomized, double-blinded, placebo-controlled trial compared a regimen of mifepristone and misoprostol with misoprostol alone for termination of early pregnancy. METHODS: 250 women with gestations < or = 56 days were randomized by a random number table to receive either 200 mg mifepristone orally or placebo followed 48 h later by 800 microg vaginal misoprostol. Administration of misoprostol was repeated every 24 h up to three doses if abortion failed to occur. Abortion success was defined as complete abortion without the use of surgical aspiration. RESULTS: Successful medical abortions occurred in 114 out of 119 subjects (95.7%) after mifepristone followed by vaginal misoprostol. In all, 110 out of 125 subjects (88.0%) successfully aborted after placebo and vaginal misoprostol. The higher success rate of complete abortion with the mifepristone and misoprostol regimen was statistically significant compared with the placebo and misoprostol regimen (P < 0.05). CONCLUSIONS: A regimen of mifepristone and misoprostol was significantly more effective for termination of pregnancies < or = 56 days than misoprostol alone. The 88% efficacy obtained with vaginal misoprostol alone may be clinically acceptable when mifepristone is not available. 相似文献
55.
Isha Jain Christine Stroka Jianying Yan Wei-Min Huang M Kathryn Iovine 《Developmental dynamics》2007,236(9):2668-2674
Fin length in the zebrafish is achieved by the distal addition of bony segments of the correct length. Genetic and molecular data provided evidence that segment growth uses a single pulse of growth, followed by a period of stasis. Examination of cell proliferation during segment growth was predicted to expose a graphical model consistent with a single burst of cell division (e.g., constant, parabolic, or exponential decay) during the lengthening of the distal-most segment. Cell proliferation was detected either by labeling animals with bromodeoxyuridine (during S-phase) or monitoring histone3-phosphate (mitosis). Results from both methods revealed that the number of proliferating cells fluctuates in apparent pulses as a segment grows (i.e., during the growth phase). Thus, rather than segment size being the result of a single burst of proliferation, it appears that segment growth is the result of several pulses of cell division that occur approximately every 60 microns (average segment length approximately 250 microns). These results indicate that segment lengthening requires multiple pulses of cell proliferation. 相似文献
56.
Jain R Chaturvedi KU Khurana N Aggarwal AK 《Indian journal of pathology & microbiology》2004,47(3):420-422
Insular carcinoma of thyroid (ICT) is a rare tumor, which accounts for 4-6% of thyroid malignancies. ICT arising from follicular cells of thyroid shows a characteristic insular growth pattern characterized by solid nests of tumor cells separated by vessels. A 52-year-old female presented with a huge swelling in midline of the neck with retrosternal extension. The patient was euthyroid. Near total thyroidectomy was done. Grossly, the tumour was involving both the lobes and isthmus of thyroid. Microscopic examination revealed features of insular carcinoma. On immunohistochemistry, tumour cells were positive for thyroglobulin and negative for calcitonin. 相似文献
57.
A human recessive neurosensory nonsyndromic hearing impairment locus is a potential homologue of the murine deafness (dn) locus 总被引:1,自引:1,他引:1
Jain Pawan K.; Fukushima Kunihiro; Deshmukh Dilip; Ramesh Arabandi; Thomas Elizabeth; Lalwani Anil K.; Kumar Subrinder; Ploplis Barbara; Skarka Hana; Srisailapathy C.R.Srikumari; Wayne Sigrid; Zbar Ross I.S.; Verma Ishwar C.; Smith Richard J.H.; Wilcox Edward R. 《Human molecular genetics》1995,4(12):2391-2394
A locus for recessive neurosensory nonsyndromic hearing impairmentmaps to chromosome 9q13q21 in two regionally separateconsanguineous families from India. Each family demonstratesa LOD score greater than 4.5 to this region. D9S15, tightlylinked to the Friedreich's ataxia locus, a region that has beendefined with over 1 Mb of YAC contig information and severalexpressed sequences, is one of the flanking markers. In mice,the deafness (dn) locus maps to mouse chromosome 19 and flankingloci are syntenic to human chromosome 9q11q21. The dnmouse is a potential model for the hearing impairment foundin both these families. 相似文献
58.
Attention deficit hyperactivity disorder (ADHD) is a prevalent psychiatric condition in children and follow up studies have indicated that 22-33% of patients continue to suffer from ADHD during late adolescence and adulthood. Convincing evidence supports the contribution of genetic factors in the etiology of ADHD, and the interaction of the psychostimulants with the dopamine system suggests that dopamine is involved in the pathophysiology. The 7-repeat allele of the 48 base pair repeat of the dopamine D4 receptor gene (DRD4) has been reported, with several replications, to be associated with ADHD in children. We tested for the presence of association between the DRD4 48 base repeat and adult ADHD in two independent samples: one comprised of cases and ethnically matched controls, and the second made up of nuclear families. Each case was assessed using a battery of adult ADHD assessment instruments. The analysis of the 66 cases and 66 controls showed a significantly higher presence of the 7-repeat in the adult ADHD patients vs. controls (chi(2) = 5.65; df = 1; P = 0.01). In the analysis of transmission of DRD4 alleles in 44 nuclear families with the transmission disequilibrium test, a trend was observed toward a increased transmission of the 7-repeat from the heterozygous parents to the affected offspring (chi(2) = 2.00; df = 1; P = 0.15). When the two samples were combined, the overall significance was stronger (N = 110; z = 2.68; P = 0.003). The results of our study suggest a role of the 7-repeat allele in adult subjects suffering from ADHD. This finding is an important continuation of the group of studies that together strongly suggest the involvement of DRD4 in ADHD. 相似文献
59.
In vitro gene expression strategy was used for the production of polyclonal antiserum to the nucleocapsid protein (NP) of Groundnut bud necrosis virus (GBNV). The GBNV NP gene from cowpea isolate was cloned into 6x His-tagged UA cloning vector and expressed in Escherichia coli [M15] cells. The fusion protein was detected in insoluble fraction and was purified by using Ni-NTA agarose resin. The purified 6x His-fusion protein (32 kDa) was used for immunisation to produce a high titre polyclonal antiserum. The antiserum to the NP of GBNV at 1:4000 dilution detected successfully natural infection of GBNV and Watermelon bud necrosis virus in a wide range of cucurbitaceous, leguminous and solanaceous hosts from different locations. 相似文献
60.
Jhingan HP Jain R Desai NG Vaswani M Tripathi BM Pandey RM 《Indian journal of medical sciences》2002,56(10):495-500
Self-report validity of recent drug use among heroin abusers depends on many factors including the population being studied and the setting in which the study is carried out. This study was conducted by the treating physicians to assess the self-report validity of recent heroin use by heroin dependent patients in the outdoor setting using 'thin layer chromatography' (TLC) and two highly sensitive methods of urinalysis viz. 'gas liquid chromatography' (GLC) and 'high performance liquid chromatography' (HPLC). Out of seventy-six heroin dependent patients who entered the study, 64 provided urine sample on the same day. Patients' self-report about recent opiate use was found to have a moderate agreement with urinalysis report. However, it is important to validate it with urinalysis during the treatment process because a substantial proportion of patients fails to report recent opiate use. It is recommended that all drug dependence treatment centres should be equipped with a sensitive urinalysis facility. Otherwise, the outcome of the treatment process should be considered with caution. 相似文献