Επιστημονικες Δημοσιευσεις

Ballian N, Rajamanickam V, Harms BA, Foley EF, Heise CP, Greenberg CC, Kennedy GD. J Trauma Acute Care Surg. 2013 Feb;74(2):611-6. doi: 10.1097/TA.0b013e31827d5d93. Department of Surgery, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53792-7375, USA. Abstract BACKGROUND: The surgical treatment of acute colonic diverticulitis is associated with significant morbidity and mortality. However, patient and operative characteristics associated with mortality in this patient population are unclear. We hypothesize that demographic and perioperative variables can be used to predict postoperative mortality.The purpose of this study was to identify perioperative variables predictive of postoperative mortality after emergent surgery for acute diverticulitis. METHODS: Patients with diverticulitis undergoing colostomy and/or partial colectomy with or without primary anastomosis were retrieved from the American College of Surgeons National Surgical Quality Improvement Program database for years 2005 to 2008 inclusive. Only patients undergoing emergent surgery for acute diverticulitis were included. Univariate analyses were performed to compare demographic characteristics, preoperative laboratory values, comorbidities, and intraoperative variables. Variables with a significant (p < 0.10) difference between survivors and nonsurvivors were included in a stepwise logistic regression model to determine predictors of 30-day mortality. Concordance indices (c indices) for postoperative mortality were calculated using 2005 to 2008 […]

Ballian N, Weisensel N, Rajamanickam V, Foley EF, Heise CP, Harms BA, Kennedy GD. World J Surg. 2012 Oct;36(10):2488-96. doi: 10.1007/s00268-012-1694-x. Department of Surgery, G4/701 Clinical Science Center, University of Wisconsin, 600 Highland Avenue, Madison, WI 53792-7375, USA. balliann@upmc.edu Abstract BACKGROUND: Laparoscopic surgery is safe and effective in the management of common abdominal emergencies. However, there is currently a lack of data about its use for emergency colorectal surgery. We hypothesized that laparoscopy can improve the postoperative outcomes of emergency restorative colon resection. METHODS: Adult patients undergoing emergent open and laparoscopic colon resection with primary anastomosis were retrieved from the American College of Surgeons National Surgical Quality Improvement Program database for the years 2005 to 2008 inclusive. Demographic and operative characteristics, laboratory values, and postoperative outcomes were compared between patients undergoing laparoscopic and open colon resection using univariate analyses, multivariate logistic regression, and propensity score analyses. RESULTS: A total of 341 laparoscopic (9.6 %) and 3211 (90.4 %) open colon resections were included. Patients undergoing laparoscopic surgery had a significantly lower prevalence of co-morbidities and better postoperative outcomes. On multivariate analysis, laparoscopic surgery was an independent predictor of a longer operating time (p < 0.001) and shorter total (p = […]

Liu SH, Smyth-Templeton N, Davis AR, Davis EA, Ballian N, Li M, Liu H, Fisher W, Brunicardi FC. Surgery. 2011 Apr;149(4):484-95. doi: 10.1016/j.surg.2010.11.014. Epub 2011 Feb 5. Michael E. DeBakey Department of Surgery, Elkins Pancreas Center, Baylor College of Medicine, Houston, TX 77030, USA. Abstract BACKGROUND: Adenoviral gene therapy has been applied widely for cancer therapy; however, transient gene expression as result of humoral immunoneutralization response to adenovirus limits its effect. The purpose of this study is to determine whether DOTAP:cholesterol liposome could shield adenovirus from neutralizing antibody and permit the use of multiple cycles of intravenous liposome encapsulated serotype 5 adenoviral rat insulin promoter directed thymidine kinase (L-A-5-RIP-TK) with ganciclovir (GCV) to enhance its effect. METHODS: The effect of multiple cycles of systemic L-A-5-RIP-TK/GCV therapy was evaluated in grouped PANC-1 SCID mice treated with different numbers of cycles. Humoral immune response to A-5-RIP-TK or L-A-5-RIP-TK was assessed using C57/B6J mice challenged with adenovirus or liposome adenovirus complex. RESULTS: The minimal residual tumor burden (3.2 ± 0.6 mm(3)) and greatest survival time (153.0 ± 6 days) were obtained in the mice receiving 4 and 3 cycles of therapy, respectively. Toxicity to islet cells associated with RIP-TK/GCV therapy was observed after […]

Ballian N, Rabiee A, Andersen DK, Elahi D, Gibson BR. Burns. 2010 Aug;36(5):599-605. doi: 10.1016/j.burns.2009.11.008. Epub 2010 Jan 13. Review. Department of Surgery, University of Wisconsin, Madison, WI, USA. Abstract Severe burn causes a catabolic response with profound effects on glucose and muscle protein metabolism. This response is characterized by hyperglycemia and loss of muscle mass, both of which have been associated with significantly increased morbidity and mortality. In critically ill surgical patients, obtaining tight glycemic control with intensive insulin therapy was shown to reduce morbidity and mortality and has increasingly become the standard of care. In addition to its well-known anti-hyperglycemic action and reduction in infections, insulin promotes muscle anabolism and regulates the systemic inflammatory response. Despite a demonstrated benefit of insulin administration on the maintenance of skeletal muscle mass, it is unknown if this effect translates to improved clinical outcomes in the thermally injured. Further, insulin therapy has the potential to cause hypoglycemia and requires frequent monitoring of blood glucose levels. A better understanding of the clinical benefit associated with tight glycemic control in the burned patient, as well as newer strategies to achieve and maintain that control, may provide improved methods to reduce the clinical morbidity and […]

Ballian N, Zarebczan B, Munoz A, Harms B, Heise CP, Foley EF, Kennedy GD. J Gastrointest Surg. 2009 Dec;13(12):2260-7. doi: 10.1007/s11605-009-0987-3. Epub 2009 Sep 2. Department of Surgery, University of Wisconsin, G4/701 Clinical Science Center, 600 Highland Avenue, Madison, WI 53792-7375, USA. Abstract BACKGROUND: Reversal of Hartmann’s is a common surgical procedure. Routine preoperative evaluation of the distal colonic/rectal remnant (DCRR) with contrast and/or endoscopic studies is frequently performed despite lack of evidence to support this practice. We hypothesize that asymptomatic patients can safely undergo Hartmann’s reversal without preoperative DCRR evaluation. METHODS: Adult patients undergoing reversal of Hartmann’s at a single institution were retrospectively identified. Operative characteristics and outcomes in patients with and without preoperative DCRR evaluation were compared. RESULTS: Between 1993 and 2008, 203 patients underwent reversal of Hartmann’s at a tertiary referral center. Sixty-eight patients (33%) did not undergo preoperative DCRR evaluation and had comparable demographic characteristics, comorbidities, DCRR length, and perioperative outcomes to 135 patients who underwent preoperative contrast and/or endoscopic studies. After evaluation, 125 (93%) patients had normal findings, seven (5%) patients had abnormal studies that did not impact their management, and three (2%) patients underwent additional procedures. CONCLUSION: Hartmann’s reversal without previous DCRR evaluation is […]

Ballian N, Adler JT, Sippel RS, Chen H. J Surg Res. 2009 Sep;156(1):16-20. doi: 10.1016/j.jss.2009.03.071. Epub 2009 May 3. Department of Surgery, University of Wisconsin Hospital and Clinics, Madison, WI 53792-7375, USA. Abstract BACKGROUND: Diagnostic tests that can accurately differentiate between benign and malignant adrenal lesions are lacking. Mass size is currently utilized as an indication for adrenalectomy in patients with adrenal masses. However, the accuracy of this criterion and the ideal size threshold are unclear. The aim of the present study was to determine the frequency of using mass size as the only indication for adrenalectomy and the ideal size threshold for distinguishing malignant primary adrenal tumors from lesions that do not require surgical resection. PATIENTS AND METHODS: The adrenalectomy database of the University of Wisconsin was retrospectively reviewed. Patients undergoing adrenalectomy for adrenal mass lesions were identified. Student’s t-test and Fisher’s exact test were used to compare continuous and noncontinuous variables respectively, with P< or =0.05 representing significance. RESULTS: Of 198 adrenalectomies performed between 1989 and 2007, 106 met inclusion criteria. There were no differences in age or gender distribution between patients with malignant and benign lesions. After complete clinical, imaging, and biochemical evaluation, mass size was the […]

Ballian N, Mahvi DM, Kennedy GD. Oncologist. 2009 Jun;14(6):580-5. doi: 10.1634/theoncologist.2008-0271. Epub 2009 May 22. Department of Surgery, University of Wisconsin, G4/701 Clinical Science Center, 600 Highland Avenue, Madison, Wisconsin 53792-7375, USA. Abstract BACKGROUND: In the absence of symptoms related to their primary tumor, patients with stage IV colorectal cancer can undergo medical treatment with their primary tumor in situ. In these patients, bowel obstruction is the most common primary tumor-related complication. We hypothesized that left-sided, circumferential, near-obstructing lesions and/or inability to advance the colonoscope beyond the primary tumor are associated with symptomatic bowel obstruction and are indications for prophylactic primary tumor resection (PTR) or colonic diversion. PATIENTS AND METHODS: The medical oncology database of the University of Wisconsin Hospital was retrospectively reviewed. Inclusion criteria were presentation with stage IV colorectal cancer without previous treatment. Student’s t-test and Fisher’s exact test were used to compare continuous and noncontinuous variables, respectively. RESULTS: Forty-nine patients met the inclusion criteria. None underwent colonic diversion or stenting during the course of their disease. At presentation, nine patients underwent PTR for obstructive symptoms. Forty percent of patients with high-risk colonoscopic lesions required PTR at presentation, compared with 3% of patients without high-risk findings. No patients […]

Ballian N, Liu SH, Brunicardi FC. World J Gastroenterol. 2008 Oct 14;14(38):5823-6. The Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX 77030, USA. Abstract AIM: To examine the expression of pancreatic duodenal homeobox-1 (PDX-1) transcription factor in human colorectal cancer. METHODS: RT-PCR, Western blotting, and immuno-histochemistry were performed to determine the expression pattern of transcription factor PDX-1 in primary colorectal tumor, hepatic metastasis, and benign colon tissue from a single patient. RESULTS: The highest PDX-1 transcription levels were detected in the metastasis material. Lower levels of PDX-1 were found to be present in the primary tumor, while normal colon tissue failed to express detectable levels of PDX-1. Western blot data revealed a PDX-1 expression pattern identical to that of mRNA expression. Immunohistochemistry confirmed high metastasis PDX-1 expression, lower levels in the primary tumor, and the presence of only traces of PDX-1 in normal colon tissue. CONCLUSION: These data argue for further evaluation of PDX-1 as a biomarker for colorectal cancer. PMID: 18855980 [PubMed – indexed for MEDLINE] PMCID: PMC2751891

Ballian N, Hu M, Liu SH, Brunicardi FC. Pancreas. 2007 Oct;35(3):199-206. Department of Surgery, The Johns Hopkins Hospital, Baltimore, MD, USA. Abstract Pancreatic disease is responsible for significant morbidity and mortality as a result of pancreatic carcinoma and diabetes mellitus. Regulation of endocrine cell mass is thought to have a central role in the pathogenesis of both these diseases. Islet cell proliferation, hypertrophy, neogenesis, and apoptosis are the main determinants of endocrine cell mass in the pancreas, and their understanding has been improved by new clues of their genetic and molecular basis. Beta cells have attracted most research interest because of potential implications in the treatment of diabetes mellitus and hypoglycemic disorders. The processes that operate during pancreatic adaptation to a changing hormonal milieu are important in pancreatic carcinogenesis. There is evidence that somatostatin and its receptors are fundamental regulators of endocrine cell mass and are involved in islet tumorigenesis. PMID: 17895838 [PubMed – indexed for MEDLINE]

Ballian N, Chrisoulidou A, Nomikos P, Samara C, Kontogeorgos G, Kaltsas GA. J Endocrinol Invest. 2007 Sep;30(8):677-83. Department of Surgery, The University of Wisconsin Hospital and Clinics, 600 Highland Avenue, Madison, WI 53792, USA. nballian@uwhealth.org Abstract Pituitary adenomas are common neoplasms requiring medical and/or surgical treatment when associated with hormonal hypersecretion. Treatment of non-functioning pituitary adenomas is necessary when symptoms of mass effect or hormonal deficits occur. However, therapeutic options, including surgical resection and/or radiotherapy, can be associated with significant complications. Hence, it is important to consider disorders that could present in a similar manner to pituitary adenomas, for which surgery is not the indicated therapeutic approach. We describe herein a 38-yr-old woman who presented with a pituitary lesion that was considered to be a non-functioning pituitary adenoma. Due to lack of hormonal deficits and/or compression of adjacent structures, we opted for conservative management and followup with consecutive magnetic resonance imaging. Fifteen months after initial diagnosis, considerable enlargement of the lesion was noted, extending mainly superiorly and indenting the optic chiasm. Repeated endocrine investigation revealed partial anterior pituitary insufficiency. The patient underwent trans-sphenoidal resection of the pituitary lesion; histology revealed a null cell pituitary adenoma and lymphocytic hypophysitis (LYH) of […]

Levy S, Zhou B, Ballian N, Li Z, Liu SH, Feanny M, Wang XP, Blanchard DK, Brunicardi FC. J Surg Res. 2006 Nov;136(1):154-60. Epub 2006 Sep 27. The Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas 77030, USA. cbrunica@bcm.tmc.edu Abstract BACKGROUND: Transcription factor PDX-1 is expressed by human pancreatic and breast cancers. Although cytotoxicity of PDX-1-directed RIP-TK/GCV gene therapy to pancreatic cancer cells has been demonstrated, the efficacy of this treatment in breast cancer cells is unknown. The purpose of this study was to determine the expression of PDX-1 and its effect on RIP activation in two human breast cancer cell lines, AU565 and T47D. We also investigated the efficacy of RIP-TK/GCV gene therapy and examined whether exogenous PDX-1 to would enhance its cytotoxic effect. MATERIALS AND METHODS: RT-PCR was used to determine PDX-1 expression. Gene constructs RSVLacZ and RIPLacZ were used for transient transfection and LacZ expression was determined using reporter assays. T47D cells were also transfected with adenoviral vectors. Cells were transfected with RIP-TK and the suboptimal level of GCV was determined for each cell line. Following GCV treatment, cytotoxicity was measured using MTS assays. The effect of exogenous PDX-1 on LacZ expression and […]

Ballian N, Brunicardi FC, Wang XP. Pancreas. 2006 Jul;33(1):1-12. Review. The Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX 77030, USA. Abstract The development of the endocrine pancreas is regulated by numerous transcription and growth factors. Somatostatin (SST) is present in many tissues and acts as a neurotransmitter and autocrine/paracrine/endocrine regulator in response to ions, nutrients, peptides, and hormones as well as neurotransmitters. In the pancreas, there is evidence that SST acts an inhibitory paracrine regulator of hormone secretion. Somatostatin receptors (SSTRs) are a family of 5 transmembrane G protein-coupled receptors, which are widely expressed in mammals including humans. SSTRs regulate multiple downstream signal transduction pathways that mediate inhibitory effects. These receptors also exhibit age- and tissue-specific expression patterns. Interactions of SST and SSTRs are not only important during normal pancreas development, but have also been implicated in many pancreatic diseases such as diabetes mellitus and pancreatic cancer. In this review article, we use evidence from recently published animal studies to present the critical roles of SST and SSTRs proteins in the development of the endocrine pancreas. PMID: 16804406 [PubMed – indexed for MEDLINE]