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991.
992.
Vedang Murthy Shwetabh Sinha Sadhana Kannan Debanjali Datta Rabi Das Ganesh Bakshi Gagan Prakash Rahul Krishnatry 《Practical radiation oncology》2019,9(5):347-353
PurposeTo determine the genitourinary (GU) toxicity outcomes in prostate cancer patients treated with stereotactic body radiation therapy (SBRT) who have undergone a prior transurethral resection of prostate (TURP) and compare it to a similar non-TURP cohort.Materials and MethodsFifty prostate cancer patients who had undergone a single TURP, had a good baseline urinary function, and had been subsequently treated with SBRT were chosen from a prospectively maintained database. These were propensity score matched to a similar non-TURP cohort treated during the same period. Matching was done for diabetes mellitus and volume of radiation therapy. Acute GU and late GU toxicity were scored using the Radiation Therapy Oncology Group (RTOG) criteria. Stricture and incontinence were scored using Common Terminology for Common Adverse Events version 4.0.ResultsMedian follow-up for the entire cohort was 26 months (non-TURP vs TURP, 30 months vs 22 months, P = .34). The median duration between TURP and start of SBRT was 10 months. There was no significant difference between non-TURP versus TURP cohort in terms of RTOG acute GU toxicities grade ≥2 (8% vs 6%, P = .45), RTOG late GU toxicities grade ≥2 (8% vs 12%, P = .10), stricture rates (4% vs 6%, P = .64), and incontinence rates (0% vs 4%, P = .15). The median duration of time to late toxicity was 16 months vs 10 months (P = .12) in non-TURP and TURP cohort, respectively.ConclusionsAlthough modestly increased as compared with non-TURP patients, GU toxicities remains low with SBRT in post-TURP patients. SBRT can be safely performed in carefully selected post-TURP prostate cancer patients. 相似文献
993.
Serena J. Scott Vasant Salgaonkar Punit Prakash E. Clif Burdette 《International journal of hyperthermia》2014,30(4):228-244
Purpose: Theoretical parametric and patient-specific models are applied to assess the feasibility of interstitial ultrasound ablation of tumours in and near the spine and to identify potential treatment delivery strategies.Methods: 3D patient-specific finite element models (n?=?11) of interstitial ultrasound ablation of tumours associated with the spine were generated. Gaseous nerve insulation and various applicator configurations, frequencies (3 and 7?MHz), placement trajectories, and tumour locations were simulated. Parametric studies with multilayered models investigated the impacts of tumour attenuation, tumour dimension, and the thickness of bone insulating critical structures. Temperature and thermal dose were calculated to define ablation (>240 equivalent minutes at 43?°C (EM43?°C)) and safety margins (<45?°C and <6 EM43?°C), and to determine performance and required delivery parameters.Results: Osteolytic tumours (≤44?mm) encapsulated by bone could be successfully ablated with 7?MHz interstitial ultrasound (8.1–16.6?W/cm2, 120–5900?J, 0.4–15?min). Ablation of tumours (94.6–100% volumetric) 0–14.5?mm from the spinal canal was achieved within 3–15?min without damaging critical nerves. 3 MHz devices provided faster ablation (390 versus 930?s) of an 18?mm diameter osteoblastic (high bone content) volume than 7?MHz devices. Critical anatomy in proximity to the tumour could be protected by selection of appropriate applicator configurations, active sectors, and applied power schemas, and through gaseous insulation. Preferential ultrasound absorption at bone surfaces facilitated faster, more effective ablations in osteolytic tumours and provided isolation of ablative energies and temperatures.Conclusions: Parametric and patient-specific studies demonstrated the feasibility and potential advantages of interstitial ultrasound ablation treatment of paraspinal and osteolytic vertebral tumours. 相似文献
994.
Shilpa Gowda Seth Lipka Ashley H. Davis-Yadley Huafeng Shen Jeffrey Silpe Andy White Sam Satler Dustin Luebbers James Statler Anna Zheng Joshua Elder Albin Abraham Prakash Viswanathan Paul Mustacchia 《Journal of gastrointestinal oncology.》2015,6(2):165-171
Background
Epidemiologic studies suggest that lower bone mineral density (BMD) is associated with an increased risk for colorectal adenoma/cancer, especially in postmenopausal women. The aim of this study is to investigate the association between osteopenia and/or osteoporosis and colorectal adenomas in patients from a New York community hospital.Methods
We performed a cross-sectional observational study on 200 patients who underwent screening colonoscopies and bone density scan (dual-energy X-ray absorptiometry) at Nassau University Medical Center from November 2009 to March 2011. Among these, 83 patients were identified as osteoporosis (T score of −2.5 or below) and 67 were osteopenia (T score between −1.0 and −2.5). Logistic regression model was performed to assess the association between osteopenia and/or osteoporosis and colorectal adenomas.Results
Among the patients with osteopenia and osteoporosis, the mean ages were 59.1 years [standard deviation (SD) =8.9] and 61.5 (SD =8.9), respectively. There were 94.0%, 85.1% and 74.7% women, respectively, in normal BMD, osteopenia and osteoporosis groups. The prevalence of colorectal adenomas was 17.9% and 25.3% in the osteopenia and osteoporosis groups, respectively, and 18.0% in the normal BMD group. After adjustment for potential confounders including age, sex, race, body mass index (BMI), tobacco use, alcohol use, history of diabetes, hypertension, or dyslipidemia, osteoporosis was found to be associated with presence of colorectal adenomas more than 2, compared to the normal BMD group. No significant associations were found for the prevalence, size, and location of adenomas.Conclusions
Our study suggests that osteoporosis is significantly associated with the presence of multiple colorectal adenomas. Prospective studies with a larger sample size are warranted in the future. 相似文献995.
Anné PR Machtay M Rosenthal DI Brizel DM Morrison WH Irwin DH Chougule PB Estopinal NC Berson A Curran WJ 《International journal of radiation oncology, biology, physics》2007,67(2):445-452
PURPOSE: Intravenous amifostine 200 mg/m2 reduces xerostomia in head-and-neck cancer patients. This Phase II study evaluated subcutaneous (s.c.) amifostine in a similar patient population. PATIENTS AND METHODS: Patients received amifostine 500 mg, administered as two 250-mg s.c. injections 60 min before once-daily radiation for head-and-neck cancer (50-70 Gy in 5-7 weeks). The primary endpoint was the incidence of > or =Grade 2 acute xerostomia. RESULTS: Fifty-four patients received s.c. amifostine and radiotherapy. The incidence of > or =Grade 2 acute xerostomia was 56% (95% CI, 43-69%) and the incidence of > or =Grade 2 late xerostomia at 1 year was 45% (95% CI, 29-61%). The incidence of acute xerostomia was lower than reported previously with no amifostine in a controlled study; rates of acute xerostomia were similar between s.c. and i.v. amifostine in the two studies. The rate of late xerostomia with s.c. amifostine was intermediate between rates for i.v. amifostine and no amifostine, and not statistically significantly different from either historical control. Grades 1-2 nausea and emesis were the most common amifostine-related adverse events. Grade 3 amifostine-related adverse events reported by >1 patient included: dehydration (11%); rash (6%); and weight decrease, mucositis, dyspnea, and allergic reaction (each 4%). Seven patients (13%) had serious cutaneous adverse events outside the injection site. One-year rates of locoregional control, progression-free survival, and overall survival were 78%, 75%, and 85%, respectively. CONCLUSIONS: Subcutaneous amifostine provides a well-tolerated yet simpler alternative to i.v. amifostine for reducing acute xerostomia in head-and-neck cancer patients. 相似文献
996.
Prakash Mishra Nishi Sonkhya Naveent Mathur 《Indian journal of otolaryngology and head and neck surgery》2007,59(3):225-228
Objective
Underlay Tympanoplasty with superiorly based circumferential flap for dry subtotal perforations.Study Design
A prospective study of cases with dry subtotal perforations, which underwent surgery between August 2001–Feb. 2004.Setting
Study was conducted on patients attending ENT OPD in S.M.S. Medical College and Hospital from August 2001–Feb. 2004 with dry subtotal perforations.Results
It was noted that 89% of the cases were in the age group of 11 to 40 years, while one case was of 7 years of age and 9% of cases were between the age of 41–50. 50% of the cases had dry ear for less than 3 months while 75% of cases had dry ear for less than 1 year. Graft take rate was 97% with completely healed tympanic membrane. Rejection of the graft was observed in 2% of the cases. Hearing gain of 10–30dB was achieved in 95% of the cases. 7% of the cases suffered minor complications like otitis media with effusion (2%) retraction (2%) and lateralization (1%).Conclusion
Duration for which ear has been dry did not affect the results. 49% of cases had dry ear for less than 3 months, with good graft take up rate and hearing gain. Pneumatization of mastoids, had a direct relationship with, post operative hearing gain, which ranged from 10–30 dB, in 95% of the cases. We observed, 97% graft take rate. Rejection of the graft was found in only 2% of the cases. 97% of the graft take rate and good hearing gain in our study can be correlated with expertise technique to deal with subtotal perforations. 相似文献997.
M. D. Prakash B. Viswanatha R. Rasika 《Indian journal of otolaryngology and head and neck surgery》2015,67(4):333-337
Endoscopic endonasal dacryocystorhinostomy (DCR), when compared to external techniques, has always had guarded acceptance primarily due to inconsistent success rates. The most common cause of surgical failure in endoscopic DCR is very high/very low mucosal incision, obstruction of neo-ostium by granulation tissue, infolding of flap or formation of synechiae between middle turbinate and the neo-ostium site post-operatively. Several techniques and modifications have been suggested by various authors over the years since the first introduction of endoscopic endonasal DCR. With the newer techniques and advancements, the success rates have become comparable or even higher than external DCR. The aim of our study was to determine the success of endoscopic endonasal DCR using the classical Wormald technique with a few modifications. A total of 37 cases of epiphora secondary to nasolacrimal duct obstruction were operated using endoscopic endonasal DCR technique. The surgical technique included classical Wormald principle of mucosal flap, removal of the overlying bone using Kerrisons punch & chisel-hammer followed by vertical incision on the sac. The medial wall of lacrimal sac was then trimmed using microdebrider, thus apposing it to the nasal mucosal flaps. The anterior end of middle turbinate was also trimmed prophylactically to prevent synechiae formation. The outcome and long term patency of the cases were evaluated. Of the 37 cases, 35 cases (94.6 %) had complete resolution of the epiphora at the end of 1 year follow up period. The two cases of failure were due to canaliculitis in one patient and extensive granulation around the neo-ostium in another. Thus the above method has very good success rate comparable to previous studies and very less chances of granulation tissue formation and blockage of neo-ostium by synechiae/flap infolding. 相似文献
998.
Brijesh B. Patel Seth Lipka Huafeng Shen Ashley H. Davis-Yadley Prakash Viswanathan 《Journal of gastrointestinal oncology.》2015,6(5):492-497
Background
Chronic hepatitis B (CHB) infection has been associated with malignancy, most notably hepatocellular carcinoma. Previous research has shown that hepatitis C is associated with increased colorectal adenomas and neoplasia. Currently, there are no studies on the association of CHB and colorectal adenomas. We aimed to identify a possible link between CHB and colorectal adenoma.Methods
A retrospective chart review was performed on 588 consecutive patients undergoing screening or diagnostic colonoscopy that were previously screened or diagnosed with hepatitis B. Comparisons between categorical variables were analyzed with Chi Square test and t-test for continuous variables. Unconditional logistic regression was used to generate age-, gender-and race-adjusted odds ratios and their 95% confidence intervals (CI) comparing medication users with non-users. Statistical analyses were performed with SAS 9.3 software.Results
A total of 487 patients were analyzed in the control group vs. 71 in the hepatitis B group. The adenoma detection rate was 23.9% in hepatitis B vs. 15.9% in the non-hepatitis B group for all cause colonoscopy; however this did not reach statistical significance. There was a significantly higher number of adenomas present in the distal colon compared to control (OR =2.16; 95% CI, 1.06-4.43; P=0.04). There were no significant findings between hepatitis B infection with size, multiplicity or presence of proximal adenomas. There was a significant difference noted in regards to smoking history, BMI and age between two groups.Conclusions
Although the adenoma detection rate was higher in hepatitis B population vs. the non-hepatitis B group this did not reach statistical significance. However, we did find an association between CHB infection and the presence of distal colorectal adenomas. Larger prospective studies are needed to strengthen our findings along with future studies examining hepatitis B virus (HBV) and mechanisms inducing colorectal carcinogenesis. 相似文献999.
Bagihalli GB Avaji PG Patil SA Badami PS 《European journal of medicinal chemistry》2008,43(12):2639-2649
A series of metal complexes of cobalt(II), nickel(II) and copper(II) have been synthesized with newly synthesized biologically active 1,2,4-triazole Schiff bases derived from the condensation of 3-substituted-4-amino-5-mercapto-1,2,4-triazole and 8-formyl-7-hydroxy-4-methylcoumarin, which have been characterized by elemental analyses, spectroscopic measurements (IR, UV-vis, fluorescence, ESR), magnetic measurements and thermal studies. Electrochemical study of the complexes is also reported. All the complexes are soluble to limited extent in common organic solvents but soluble to larger extent in DMF and DMSO and are non-electrolytes in DMF and DMSO. All these Schiff bases and their complexes have also been screened for their antibacterial (Escherichia coli, Staphylococcus aureus, Streptococcus pyogenes, Pseudomonas aeruginosa and Salmonella typhi) and antifungal activities (Aspergillus niger, Aspergillus flavus and Cladosporium) by MIC method. The brine shrimp bioassay was also carried out to study their in vitro cytotoxic properties. 相似文献
1000.