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61.
Cancer mortality in relatives of retinoblastoma patients 总被引:3,自引:0,他引:3
L C Strong J Herson C Haas K Elder R Chakraborty K M Weiss P Majumder 《Journal of the National Cancer Institute》1984,73(2):303-311
The risk of other cancers in relatives of retinoblastoma (RTB) patients was determined by a survey of the mortality experience of siblings, parents, parental siblings, and grandparents of all U.S. or Canadian RTB patients referred to The University of Texas M.D. Anderson Hospital and Tumor Institute between 1944 and 1980. Expected mortality was ascertained by the application of age-, sex-, race-, and calendar year-specific U.S. mortality rates to the observed person-years. Among 607 relatives of 33 unilateral-sporadic RTB probands, no excess in cancer deaths was observed (observed/expected = 18/22). Among 733 relatives of 47 bilateral-familial RTB probands, a slight excess in cancer deaths was observed (41/31). A significant excess in cancer deaths was occurred in relatives under age 55 years (18/9) and in fathers (7/1) of the bilateral RTB probands. To determine whether the cancer excess was related to some unique allele associated with second tumors in RTB survivors, the cancer mortality of 203 relatives of the 14 RTB patients with second tumors was examined, and no excess was observed (11/11). To determine whether the excess might be attributable to an unexpressed RTB gene or precursor, the mortality experience was examined in 6 kindreds in which parents, unaffected by RTB, had more than 1 child with RTB. Among these 72 relatives a significant excess in cancer deaths was observed (8/2). The findings demonstrate a modest overall cancer excess in relatives of hereditary RTB patients and suggest it may be attributable to an unexpressed RTB gene or precursor in a small number of kindreds. Mechanisms for an apparent "precursor" might involve a delayed mutation, genetic mosaicism, or a submicroscopic balanced chromosomal translocation. 相似文献
62.
Nikhil Ailaney William L. Johns Gregory J. Golladay Benjamin Strong Niraj V. Kalore 《The Journal of arthroplasty》2021,36(7):2402-2411
BackgroundPersistent wound drainage after total joint arthroplasty (TJA) increases the risk of surgical site infections (SSIs). Closed incision negative pressure wound therapy (ciNPWT) decreases infections in traumatic wounds, but evidence for its use after elective TJA is limited. The purpose of this meta-analysis of level I studies is to determine the effect of ciNPWT on risk of SSI and wound complications following TJA.MethodsMEDLINE, EMBASE, CINAHL, and Cochrane Library were searched for randomized controlled trials comparing ciNPWT vs standard dressings after total hip (THA) and total knee arthroplasty (TKA). Studies exclusively involving THA for femoral neck fractures were excluded. Risk of SSI and noninfectious wound complications (blisters, seroma, hematoma, persistent drainage, dehiscence, and wound edge necrosis) following TJA were analyzed.ResultsSSI risk was lower with ciNPWT compared to standard dressings (3.4% vs 7%; relative risk [RR] 0.48, P = .007), specifically in revision THA and TKA (4.1% vs 10.5%; RR 0.41, P = .03). ciNPWT increased the noninfectious complication risk after primary TKA (RR 4.71, P < .0001), especially causing wound blistering (RR 12.66, P < .0001). ciNPWT decreased hospital length of stay by 0.73 days (P = .04) and reoperation rate (RR 0.28, P = .01).ConclusionciNPWT decreases SSI risk compared to standard dressings after revision TJA, but not primary TJA. ciNPWT is associated with >12-fold increased risk of wound blistering after primary TKA. ciNPWT plays a role in revision TJA management, but additional randomized controlled trials with uniform wound assessment methods must be performed to sufficiently power findings and draw conclusions on the use of ciNPWT after primary TJA. 相似文献
63.
Marysol Luna Jason D Guss Laura S Vasquez-Bolanos Macy Castaneda Manuela Vargas Rojas Jasmin M Strong Denise A Alabi Sophie D Dornevil Jacob C Nixon Erik A Taylor Eve Donnelly Xueyan Fu M Kyla Shea Sarah L Booth Rodrigo Bicalho Christopher J Hernandez 《Journal of bone and mineral research》2021,36(9):1823-1834
Modifications to the constituents of the gut microbiome influence bone density and tissue-level strength, but the specific microbial components that influence tissue-level strength in bone are not known. Here, we selectively modify constituents of the gut microbiota using narrow-spectrum antibiotics to identify components of the microbiome associated with changes in bone mechanical and material properties. Male C57BL/6J mice (4 weeks) were divided into seven groups (n = 7–10/group) and had taxa within the gut microbiome removed through dosing with: (i) ampicillin; (ii) neomycin; (iii) vancomycin; (iv) metronidazole; (v) a cocktail of all four antibiotics together (with zero-calorie sweetener to ensure intake); (vi) zero-calorie sweetener only; or (vii) no additive (untreated) for 12 weeks. Individual antibiotics remove only some taxa from the gut, while the cocktail of all four removes almost all microbes. After accounting for differences in geometry, whole bone strength was reduced in animals with gut microbiome modified by neomycin (−28%, p = 0.002) and was increased in the group in which the gut microbiome was altered by sweetener alone (+39%, p < 0.001). Analysis of the fecal microbiota detected seven lower-ranked taxa differentially abundant in animals with impaired tissue-level strength and 14 differentially abundant taxa associated with increased tissue-level strength. Histological and serum markers of bone turnover and trabecular bone volume per tissue volume (BV/TV) did not differ among groups. These findings demonstrate that modifications to the taxonomic components of the gut microbiome have the potential to decrease or increase tissue-level strength of bone independent of bone quantity and without noticeable changes in bone turnover. © 2021 American Society for Bone and Mineral Research (ASBMR). 相似文献
64.
65.
L Ozzello CM De Rosa EW Blank K Cantell RL Ceriani DV Habif Sr 《Breast cancer research and treatment》1993,25(3):265-276
Summary An immunoconjugate composed of natural interferon (nIFN) bound in a noncleavable fashion to a monoclonal antibody (MoAb) recognizing a breast epithelial membrane mucin (Mc5) was used to treat xenografts of a human mammary carcinoma cell line (MCF-7) growing in nude mice. The immunoconjugate (nIFN/Mc5) was administered as 20 intralesional (i.l.) injections to 1 of 2 xenografts in each animal. It was found that nIFN/Mc5 produced a significant enhancement of the growth inhibitory actions of nIFN on the injected tumors. Further enhancement was obtained when nIFN or nIFN together with Mc5 (at a dose 10 times larger than that present in nIFN/Mc5) were added to the immunoconjugate. Biodistribution experiments showed that the uptake of125I-nIFN/Mc5 by the tumors was greater and its elimination slower than for125I-nIFN alone or conjugated to irrelevant mouse IgG1. In addition, the immunoconjugate up-regulated the antigenic expression of a breast epithelial membrane mucin by the carcinoma cells, an up-regulation which was not significantly different from that produced by nIFN alone. The contralateral noninjected tumors exposed to systemic levels of the immunoconjugate showed an enhancement of antitumor effects, but to a lesser extent than the injected tumors. These findings suggest that the enhancement of the growth inhibitory action of the immunoconjugate was related to the specific binding of Mc5 which targeted the IFN to the carcinoma cells and impeded its elimination. It is likely that the targeting was favored by the IFN-mediated up-regulation of antigenic expression by the carcinoma cells, thereby producing a cascade of interrelated effects. The results of this study point out the feasibility and potential usefulness of IFN treatment by means of immunoconjugates as well as the worth of pursuing and improving this form of therapy. 相似文献
66.
Germline p53 mutations are associated with cancer predisposition in Li-Fraumeni families as well as in individuals with component tumors of the syndrome. In the majority of cases these mutations have been shown to be inherited rather than de novo. We screened 59 children with primary bone or soft tissue sarcomas. Germline p53 mutations were identified in 2 patients. Interestingly, analysis revealed that both mutations were de novo. Although the frequency of germline p53 mutations in primary pediatric sarcoma patients is low, there is evidence for the importance of considering pediatric patients for testing for de novo mutations. 相似文献
67.
68.
To find out the efficacy of sucralfate in preventing gastrointestinal side effects of non-steroidal anti-inflammatory drugs (NSAIDs) a prospective, randomised single blind study was conducted from 1989 to 1992. Patients with osteoarthritis, rheumatoid arthritis and other long standing painful conditions, who were expected to receive NSAIDs for over three months, were recruited into the study. All medicines were discontinued for a period of 10–15 days prior to initial endoscopic assessment. NSAID therapy was started and the patients were randomised to receive either placebo (group A) or sucralfate (group B) in addition. Patient were reassessed clinically every week and an endoscopic examination was repeated after 6–8 weeks of follow-up. A total of 176 patients were studied in group A (n=91) and group B (n=85). At the end of 8 weeks gastrointestinal symptoms were present in 30.6% and 26.4% patients of group A and B respectively. Endoscopic assessment showed superficial lesions in 36.5% and 18.7% while endoscopic ulcer in 2.4% and 1.1% patients of groups A and B respectively. Thus in patients receiving chronic NSAID therapy, simultaneous administration of sucralfate reduces the incidence of superficial gastric lesions but has no significant effect on symptoms or ulcer formation.KEY WORDS: Gastropathy, Sucralfate, Nonsteroidal anti-inflammatory drugs 相似文献
69.
In this report, we describe the clinical, topographical and immunohistochemical characteristics of neurofilament (NF) inclusion formation induced by the intracisternal inoculation of young adult New Zealand white rabbits at 28-day intervals with 100 g AlCl3 over the course of 267 days. The ability to recover following cessation of aluminum exposure has also been assessed. The extent of neurofilamentous inclusion formation was proportionate to the cumulative amount of AlCl3 inoculated and initially consisted of fusiform axonal distention in the ventral spinal cord at day 51 following the initial inoculum. Spinal motor neuron perikaryal inclusions and discrete axonal spheroids were observed at day 107 and supraspinal neurofilamentous pathology by day 156. Perikaryal inclusions were immunoreactive to antibodies recognizing both poorly phosphorylated (SMI 32) and more highly phosphorylated high molecular weight NF (NFH). In contrast, axonal spheroids were intensely immunoreactive at all stages with antibodies recognizing highly phosphorylated NFH and an age-dependent NFH phosphorylation state (SMI 34) with only faint SMI 32 immunoreactivity. Immunoreactivity to an antibody recognizing ubiquitin-protein conjugates did not appear until day 156, whereas inclusions were not immunoreactive to antibodies recognizing either phosphatase-dependent or-independent microtubule-associated protein tau at any stage. Upon withdrawal from further AlCl3 exposure after intervals of 51, 107 or 156 days following the initial inoculum, clinical recovery ensued in all rabbits. In all but the most severely affected rabbits, perikaryal neurofilamentous inclusions resolved. However, axonal spheroids continued to be prominent. However, axonal spheroids continued to be prominent. These studies demonstrate that the repetitive intracisternal inoculation of AlCl3 in New Zealand white rabbits induces a reversible process of neurofilamentous inclusion formation that preferentially affects motor neurons, and in which recovery will occur in those inclusions containing an admixture of both poorly and highly phosphorylated NFH. 相似文献
70.
Strong J Tooth L Unruh A 《Canadian journal of occupational therapy. Revue canadienne d'ergothérapie》1999,66(5):221-228
In recent years there has been a growing awareness amongst health professionals of the need to prepare undergraduate students more adequately for practice with clients who have pain. Occupational therapists have a central role in enabling such clients to have productive lives despite pain. In this study, an examination was made of the adequacy of preparation for pain practice in graduates from one Australian occupational therapy curriculum. Recent occupational therapy graduates from the University of Queensland, Australia, who responded to a postal survey, obtained an overall 53% correct response rate to a 69-item pain knowledge and attitudes questionnaire. Results indicated the need for further education in this area, especially in the areas of pharmacological management, and pain assessment and measurement. These results were comparable to those obtained from final year occupational therapy students at Dalhousie University in Halifax, Nova Scotia prior to undertaking an elective course about pain. Follow-up interviews with a number of new graduates supported the inclusion of an elective pain course in the undergraduate occupational therapy curriculum at the University of Queensland in Australia. 相似文献