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91.
Caffeine induces loss of calcium and influences the normal development of bone. This study investigated the effects of coffee on bone metabolism in rats by biochemical measurement of calcium, bone densitometry and histometry. Male rats, born of female treated daily with coffee and with coffee intake since born, were anesthetized, subjected to extraction of the upper right incisor, and sacrificed 7, 21 and 42 days after surgery. Blood and urine samples were taken, and their maxilla radiographed and processed to obtain 5-μm-thick semi-serial sections stained with hematoxylin and eosin. The volume and bone quality were estimated using an image-analysis software. The results showed significantly greater amount of calcium in the plasma (9.40 ± 1.73 versus 9.80 ± 2.05 mg%) and urine (1.00 ± 0.50 versus 1.25 ± 0.70 mg/24 h) and significantly less amount in bone (90.0 ± 1.94 versus 86.0 ± 2.12 mg/mg bone), reduced bone mineral density (1.05 ± 0.11 versus 0.65 ± 0.15 mmAL), and lower amount of bone (76.19 ± 1.6 versus 53.41 ± 2.1 %) (ANOVA; p≤0.01) in animals treated with coffee sacrificed after 42 days. It may be concluded that coffee/caffeine intake caused serious adverse effects on calcium metabolism in rats, including increased levels of calcium in the urine and plasma, decreased bone mineral density and lower volume of bone, thus delaying the bone repair process.  相似文献   
92.

OBJECTIVE

To evaluate screening cystoscopy as the long‐term follow up in patients with an enterocystoplasty for ≥10 years.

PATIENTS AND METHODS

We performed a prospective analysis of 92 consecutive patients who attended our endoscopy suite for regular check cystoscopy as per standard follow‐up. This is performed for all patients with cystoplasty performed at our institute after 10 years. The data were recorded on patient demographics, original diagnosis and type of cystoplasty. In all, 53 of these patients consented to undergo bladder biopsies at the same time.

RESULTS

The median (range) follow‐up was 15 (10–33) years. No cancer was identified with either surveillance cystoscopy or on routine biopsies. Chronic inflammation was identified in 25 biopsies (27%). Villous atrophy was present in 12 (55%) ileal patch and three (12.5%) colonic patch biopsies. During this study, the first and only case of malignancy in a cystoplasty at our institution was diagnosed in a symptomatic patient. She had intermittent haematuria and recurrent urinary tract infections (UTIs). She previously had a normal surveillance cystoscopy.

CONCLUSIONS

We feel that it is not necessary to perform yearly check cystoscopies in patients with augmented bladders at least in the first 15 years, as cancer has not yet been detected with surveillance cystoscopy in this patient group. However, if the patient develops haematuria or other worrisome symptoms including suprapubic pain and recurrent unexplained UTIs a full evaluation, including cystoscopy and computerized tomography should be undertaken.  相似文献   
93.
94.
Disease-modifying anti-rheumatic drugs (DMARDs) are effective treatments for inflammatory arthritis but carry an increased risk of infection. For patients undergoing surgery, there is a need to consider the trade-off between a theoretical increased risk of infection with continuation of DMARDs perioperatively versus an increased risk of disease flare if they are temporarily withheld. We used the Grading of Recommendations Assessment, Development and Evaluation methodology to develop recommendations for perioperative use of DMARDs for people with inflammatory arthritis undergoing elective surgery. The recommendations form part of the National Health and Medical Research Council-endorsed Australian Living Guideline for the Pharmacological Management of Inflammatory Arthritis. Conditional recommendations were made against routinely discontinuing conventional synthetic and biologic (b) DMARDs in the perioperative period but to consider temporary discontinuation of bDMARDs in individuals with a high risk of infection or where the impact of infection would be severe. A conditional recommendation was made in favour of temporary discontinuation of targeted synthetic DMARDs in the perioperative period.  相似文献   
95.
96.
97.
Several studies suggest that protracted continuous Infusion constitutes an important way to optimize the dose and the efficacy of 5-fluorouracil (5-FU) in metastatic cancer. Eighty-three women aged 27-76 (median age 55) with metastatic breast cancer were treated every 4 weeks with a continuous ambulatory venous infusion of 5-FU 350 mg/m2/day and oral cyclophosphamide 100 mg/m2/day over 15 days. The continuous therapy was associated with a weekly administration of vincristine (0.8 mg/m2) and doxorubicin (15 mg/m2) on day 1, day 8, and day 15. Cycles were repeated every 28 days. Thirty-four patients were treated in first-line metastatic chemotherapy and 49 in second-line. Toxicities included: mucositis (grade ≤ 2) 23%, diarrhea (grade ≤ 2) 7%, a hand-foot syndrome (grade ≤ 2) 9%, alopecia (grade 3) 21%, neurological (grade ≤ 2) 4%, grade 3 and 4 leukopenia 29%, and grade 3 and 4 thrombopenia 8%. Heart toxicity was only 3%. Catheter infection was observed in 1 case and 7 patients experienced thrombosis. The overall objective response rate (OR) was 48% and the complete response rate was 23%. The median duration of response was 10 months. The median survival was 16 months. Activity was better in naive than pretreated women (respectively, 55% and 42% of OR, p = 0.21). Analysis of responses according to the metastatic sites shows the pronounced efficacy on soft tissus diseases (skin recurrences 42%, lymph nodes 52%), and also in visceral metastases (hepatic 36%, lung 34%).  相似文献   
98.
Tourniquet use in the previously revascularized ipsilateral lower extremity varies among micro-reconstructive surgeons due to the possible complication of graft failure. Examination of evidence-based literature and a current standard of care is needed to establish guidelines for such tourniquet use. Surveys were sent to vascular surgery program directors of ACGME-accredited residency programs to assess prevailing tourniquet use instruction. The survey addressed issues, including tourniquet use in previous bypass surgery, previous angioplasty, and location relative to graft anatomy. Twenty-eight responses were received out of 87 surveys sent (32 percent response rate). Ninety-three percent considered tourniquet use inappropriate in the ipsilateral lower extremity with previous revascularization. Seventy-one percent indicated tourniquet use inappropriate in previous ipsilateral angioplasty. Sixty-one percent regarded graft conduit type to be important in tourniquet use. There remains a lack of prospective, randomized, controlled studies determining risks of occlusion and other complications to the preexisting bypass graft during tourniquet use. Until such studies are done, this survey recommends avoiding tourniquet use in this patient population.  相似文献   
99.
To understand how chloroquine (CQ) enhances transgene expression in polycation-based, nonviral gene delivery systems, a number of CQ analogues with variations in the aliphatic amino side chain or in the aromatic ring are synthesized and investigated. Our studies indicate that the aliphatic amino moiety of CQ is essential to provide increased gene expression. Further, the enhancements are more dramatically affected by changes to the aromatic ring and are positively correlated to the strength of intercalation between DNA and the CQ analogues. Quinacrine (QC), a CQ analogue with a fused acridinyl structure that can strongly intercalate DNA, enhances transfection similarly to CQ at a concentration 10 times lower, while N(4)-(4-pyridinyl)-N(1),N(1)-diethyl-1,4-pentanediamine (CP), a CQ analogue that has a weakly intercalating pyridinyl ring, shows no effect on gene expression. Subtle change on the 7-substituent of the chloroquine aromatic structure can also greatly affect the ability of the CQ analogues to enhance transgene expression. Transfection in the presence of N(4)-(7-trifluoromethyl-4-quinolinyl)-N(1),N(1)-diethyl-1,4-pentanediamin e (CQ7a) shows expression efficiency 10 times higher than in the presence of CQ at same concentration, while transfection in the presence of N(4)-(4-quinolinyl)-N(1),N(1)-diethyl-1,4-pentanediamine (CQ7b) does not reveal any enhancing effects on expression. Through a number of comparative studies with CQ and its analogues, we conclude that there are at least three mechanistic features of CQ that lead to the enhancement in gene expression: (i) pH buffering in endocytic vesicles, (ii) displacement of polycations from the nucleic acids in polyplexes, and (iii) alteration of the biophysical properties of the released nucleic acid.  相似文献   
100.
Short nucleic acid sequences specific to oncogene targets such as bcl-2, bcr-abl, and c-myc have been shown to exhibit specific anti-cancer activity in vitro through antigene or antisense activity. Efficient in vivo delivery of oligonucleotides remains a major limitation for the therapeutic application of these molecules. We report herein on the preparation of transferrin-modified nanoparticles containing DNAzymes (short catalytic single-stranded DNA molecules) for tumor targeting as well as their biodistribution using various methods of administration in the mouse. Linear, beta-cyclodextrin-based polymers are complexed with DNAyzme molecules to form sub-50 nm particles termed "polyplexes". The surface properties of the cyclodextrin-containing polyplexes are modified by exploiting the ability of the beta-cyclodextrin substructure and adamantane to form inclusion complexes. Accordingly, conjugates of adamantane with poly(ethylene glycol) (PEG) are prepared and combined with the polyplexes. The adamantane form inclusion complexes with the surface cyclodextrins of the polyplexes to provide a sterically stabilizing layer of PEG. The stabilized polyplexes are also modified with transferrin for increasing targeting to tumor cells expressing transferrin receptors. The preparation, characterization, and in vitro application of these nanoparticles are discussed. The transferrin-polyplexes containing fluorescently-labeled DNAzyme molecules are administered to tumor-bearing nude mice and their biodistribution and clearance kinetics are monitored using a fluorescence imaging system. Four methods of administration are studied: intraperitoneal bolus and infusion, intravenous bolus, and subcutaneous injection. DNAzymes packaged in polyplex formulations are concentrated and retained in tumor tissue and other organs, whereas unformulated DNAzyme is eliminated from the body within 24 hours post-injection. Intravenous and intraperitoneal bolus injections result in the highest fluorescent signal (DNAzyme) at the tumor site. Tumor cell uptake is observed with intravenous bolus injection only, and intracellular delivery requires transferrin targeting.  相似文献   
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