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Probiotics are organisms which provide a desired and beneficial effect on human health. With recent evidence implicating a disruption in the balance of the gastrointestinal microbiome and intestinal immunity as a potential trigger for inflammatory bowel disease (IBD), there has been growing interest in using probiotics as an adjunct to standard anti-inflammatory and immune suppressing therapy. Animal models describe potential and plausible mechanisms of action for probiotics to counter inflammation of colonic mucosa. Although there are insufficient data to recommend probiotics in ulcerative colitis or Crohn's disease, good evidence supports the use of specific probiotics for maintenance of remission in pouchitis. Although there are limited regulatory standards for the agents, probiotics are relatively safe with minimal reported side effects or contraindications. More rigorous studies need to be published supporting efficacy and safety of these agents before they become a mainstay of IBD medical treatment. 相似文献
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Ganesh Sankaranarayanan Kai Matthes Arun Nemani Woojin Ahn Masayuki Kato Daniel B. Jones Steven Schwaitzberg Suvranu De 《Surgical endoscopy》2013,27(5):1607-1616
Introduction and study aim
Natural orifice translumenal endoscopic surgery (NOTES) is an emerging surgical technique that requires a cautious adoption approach to ensure patient safety. High-fidelity virtual-reality-based simulators allow development of new surgical procedures and tools and train medical personnel without risk to human patients. As part of a project funded by the National Institutes of Health, we are developing the virtual transluminal endoscopic surgery trainer (VTEST?) for this purpose. The objective of this study is to conduct a structured needs analysis to identify the design parameters for such a virtual-reality-based simulator for NOTES.Methods
A 30-point questionnaire was distributed at the 2011 National Orifice Surgery Consortium for Assessment and Research meeting to obtain responses from experts. Ordinal logistic regression and the Wilcoxon rank-sum test were used for analysis.Results
A total of 22 NOTES experts participated in the study. Cholecystectomy (CE, 68 %) followed by appendectomy (AE, 63 %) (CE vs AE, p = 0.0521) was selected as the first choice for simulation. Flexible (FL, 47 %) and hybrid (HY, 47 %) approaches were equally favorable compared with rigid (RI, 6 %) with p < 0.001 for both FL versus RI and HY versus RI. The transvaginal approach was preferred 3 to 1 to the transgastric. Most participants preferred two-channel (2C) scopes (65 %) compared with single (1C) or three (3C) or more channels with p < 0.001 for both 2C versus 1C and 2C versus 3C. The importance of force feedback and the utility of a virtual NOTES simulator in training and testing new tools for NOTES were rated very high by the participants.Conclusion
Our study reinforces the importance of developing a virtual NOTES simulator and clearly presents expert preferences. The results of this analysis will direct our initial development of the VTEST? platform. 相似文献67.
Yair Lotan Aditya Bagrodia Niccolo Passoni Varun Rachakonda Payal Kapur Yull Arriaga Christian Bolenz Vitaly Margulis Ganesh V. Raj Arthur I. Sagalowsky Shahrokh F. Shariat 《European urology》2013
Background
Retrospective studies demonstrated that cell cycle–related and proliferation biomarkers add information to standard pathologic tumor features after radical cystectomy (RC). There are no prospective studies validating the clinical utility of markers in bladder cancer.Objective
To prospectively determine whether a panel of biomarkers could identify patients with urothelial carcinoma of the bladder (UCB) who were likely to experience disease recurrence or mortality.Design, setting, and participants
Between January 2007 and January 2012, every patient with high-grade bladder cancer, including 216 patients treated with RC and lymphadenectomy, underwent immunohistochemical staining for tumor protein p53 (Tp53); cyclin-dependent kinase inhibitor 1A (p21, Cip1) (CDKN1A); cyclin-dependent kinase inhibitor 1B (p27, Kip1); antigen identified by monoclonal antibody Ki-67 (MKI67); and cyclin E1.Intervention
Every patient underwent RC and lymphadenectomy, and marker staining.Outcome measurements and statistical analysis
Cox regression analyses tested the ability of the number of altered biomarkers to predict recurrence or cancer-specific mortality (CSM).Results and limitations
Pathologic stage among the study population was pT0 (5%), pT1 (35%), pT2 (19%), pT3 (29%), and pT4 (13%); lymphovascular invasion (LVI) was seen in 34%. The median number of removed lymph nodes was 23, and 60 patients had lymph node involvement (LNI). Median follow-up was 20 mo. Expression of p53, p21, p27, cyclin E1, and Ki-67 were altered in 54%, 26%, 46%, 15%, and 75% patients, respectively. In univariable analyses, pT stage, LNI, LVI, perioperative chemotherapy (CTx), margin status, and number of altered biomarkers predicted disease recurrence. In a multivariable model adjusting for pathologic stage, margins, LNI, and adjuvant CTx, only LVI and number of altered biomarkers were independent predictors of recurrence and CSM. The concordance index of a baseline model predicting CSM (including pathologic stage, margins, LVI, LNI, and adjuvant CTx) was 80% and improved to 83% with addition of the number of altered markers.Conclusions
Molecular markers improve the prediction of recurrence and CSM after RC. They may identify patients who might benefit from additional treatments and closer surveillance after cystectomy. 相似文献68.
Ganesh Sankaranarayanan Rajeswara R. Resapu Daniel B. Jones Steven Schwaitzberg Suvranu De 《Surgical endoscopy》2013,27(9):3056-3072
Background
Instruments that apply energy to cut, coagulate, and dissect tissue with minimal bleeding facilitate surgery. The improper use of energy devices may increase patient morbidity and mortality. The current article reviews various energy sources in terms of their common uses and safe practices.Methods
For the purpose of this review, a general search was conducted through NCBI, SpringerLink, and Google. Articles describing laparoscopic or minimally invasive surgeries using single or multiple energy sources are considered, as are articles comparing various commercial energy devices in laboratory settings. Keywords, such as laparoscopy, energy, laser, electrosurgery, monopolar, bipolar, harmonic, ultrasonic, cryosurgery, argon beam, laser, complications, and death were used in the search.Results
A review of the literature shows that the performance of the energy devices depends upon the type of procedure. There is no consensus as to which device is optimal for a given procedure. The technical skill level of the surgeon and the knowledge about the devices are both important factors in deciding safe outcomes.Conclusions
As new energy devices enter the market increases, surgeons should be aware of their indicated use in laparoscopic, endoscopic, and open surgery. 相似文献69.
Likun Zhang Ganesh Sankaranarayanan Venkata Sreekanth Arikatla Woojin Ahn Cristol Grosdemouge Jesse M. Rideout Scott K. Epstein Suvranu De Steven D. Schwaitzberg Daniel B. Jones Caroline G. L. Cao 《Surgical endoscopy》2013,27(10):3603-3615
Background
Mastering laparoscopic surgical skills requires considerable time and effort. The Virtual Basic Laparoscopic Skill Trainer (VBLaST-PT©) is being developed as a computerized version of the peg transfer task of the Fundamentals of Laparoscopic Surgery (FLS) system using virtual reality technology. We assessed the learning curve of trainees on the VBLaST-PT© using the cumulative summation (CUSUM) method and compared them with those on the FLS to establish convergent validity for the VBLaST-PT©.Methods
Eighteen medical students from were assigned randomly to one of three groups: control, VBLaST-training, and FLS-training. The VBLaST and the FLS groups performed a total of 150 trials of the peg-transfer task over a 3-week period, 5 days a week. Their CUSUM scores were computed based on predefined performance criteria (junior, intermediate, and senior levels).Results
Of the six subjects in the VBLaST-training group, five achieved at least the “junior” level, three achieved the “intermediate” level, and one achieved the “senior” level of performance criterion by the end of the 150 trials. In comparison, for the FLS group, three students achieved the “senior” criterion and all six students achieved the “intermediate” and “junior” criteria by the 150th trials. Both the VBLaST-PT© and the FLS systems showed significant skill improvement and retention, albeit with system specificity as measured by transfer of learning in the retention test: The VBLaST-trained group performed better on the VBLaST-PT© than on FLS (p = 0.003), whereas the FLS-trained group performed better on the FLS than on VBLaST-PT© (p = 0.002).Conclusions
We characterized the learning curve for a virtual peg transfer task on the VBLaST-PT© and compared it with the FLS using CUSUM analysis. Subjects in both training groups showed significant improvement in skill performance, but the transfer of training between systems was not significant. 相似文献70.
Anupam Das S.V. Arya Nikhil Soni Ganesh G. Gowda Dheer Singh Kalwaniya 《International journal of surgery case reports》2013,4(1):139-141
INTRODUCTIONMalignant fibrous histiocytoma is one of the most common soft tissue sarcomas in late adult life. But primary visceral malignant fibrous histiocytoma is a very rare entity. In peripheries, it is known to have an aggressive behavior but its biological pattern when involving liver and spleen is not well understood due to the rarity of its occurrence.PRESENTATION OF CASEA case of malignant fibrous histiocytoma of the liver and spleen as multiple cystic lesions in a 30 years old man is reported. The patient presented with hepatosplenomegaly resulting in central abdominal distention. Pre-operative investigations pointed toward the diagnosis of malignant cystic disease. The tumor presented as multiple hepatic cysts with massive hepatomegaly and splenomegaly. These cysts contained hemorrhagic fluid. Biopsy revealed highly cellular pleomorphic spindle cells fascicles arranged in storiform pattern at places with frequent mitoses. Immunohistochemistry revealed viamentin positivity. The tumor is compared with previous case reports.DISCUSSIONMalignant fibrous histiocytoma of liver and spleen has been mentioned in the literature as isolated case reports and most of these present as solid lesions but presentation as multiple cysts is also a possibility as was seen in this patient. It can be confirmed only on histo-pathology supported by immunohistochemistry. The disease carries guarded prognosis due to its rapid progression and diagnostic dilemma pre-operatively.CONCLUSIONThis rare malignancy affecting the viscera can be diagnosed only with high index of suspicion and awareness regarding its presentation can help surgeons deal with it. 相似文献