Mechanical/Physical Methods of Cell Disruption and Tissue Homogenization.

This chapter covers the various methods of mechanical cell disruption and tissue homogenization that are currently commercially available for processing small samples s < 1 mL) to larger multikilogram production quantities. These mechanical methods of lysing do not introduce chemicals or enzymes to the system. However, the energies required when using these "harsh," high mechanical energy methods can be enough to damage the very components being sought.The destruction of cell membranes and walls is effected by subjecting the cells (a) to shearing by liquid flow, (b) to exploding by pressure differences between inside and outside of cell, (c) to collision forces by impact of beads or paddles, or (d) a combination of these forces.Practical suggestions to optimize each method, where to acquire such equipment, and links to reference sources are included. Several novel technologies are presented.

Immune status does not predict high-risk HPV in anal condyloma.

BACKGROUND: More than 90% of anal condyloma is attributed to nonhigh risk strains of human papillomavirus (HPV), thus patients with anal condyloma do not necessarily undergo HPV serotyping unless they are immunocompromised (IC). We hypothesized that IC patients with anal condyloma have a higher risk of high-risk HPV and dysplasia than nonimmunocompromised (NIC) patients. METHODS: We performed a retrospective chart review of patients who underwent surgical treatment by a single surgeon for anal condyloma from 1/2000 to 1/2012. HPV serotyping was performed on all patient samples. We compared incidence of high-risk HPV and dysplasia in condyloma specimens from IC and NIC patients. RESULTS: High-risk HPV was identified in 14 specimens with serotypes 16, 18, 31, 33, 51, 52, and 67. Twenty-two cases (18.3%) had dysplasia. Invasive carcinoma was identified in one IC patient. The prevalence of dysplasia or high-risk HPV was not significantly different between IC and NIC groups. High-risk HPV was a significant independent predictor of dysplasia (odds ratio [OR] = 5.2; 95% CI = 1.24-21.62). Immune status, however, was not a significant predictor of high-risk HPV (OR = 1.11; 95% CI = 0.16-5.12) nor dysplasia (OR = 0.27; 95% CI = 0.037-1.17). CONCLUSIONS: IC patients did not have a significantly higher prevalence or risk of high-risk HPV or dysplasia in our study. HPV typing of all condylomata, regardless of immune status, should be considered as it may help predict risk of neoplastic transformation or identify NIC patients with an increased risk of developing anal intraepithelial neoplasia.

Mechanical/physical methods of cell distribution and tissue homogenization.

This chapter covers the various methods of Mechanical Cell Disruption and Tissue Homogenization that are currently commercially available for processing minute samples (<1 mL) to larger production quantities. These mechanical methods of lysing do not introduce chemicals or enzymes to the system. However, the energies needed when using these "harsh" methods can be high and destroy the very proteins being sought.The destruction of cell membranes and walls by these "harsh" methods is effected by subjecting the cells (1) to shearing by liquid flow, (2) to exploding by pressure differences between inside and outside of cell, (3) to collision forces by impact of beads or paddles, or (4) a combination of these forces. Practical suggestions to optimize each method, where to acquire such equipment, and links to reference sources are included.

Clinical outcomes of perineal proctectomy among patients of advanced age.

BACKGROUND: Rectal prolapse occurs primarily in older patients who often have significant comorbidities. With the aging population, increasing numbers of elderly patients are presenting with rectal prolapse. The perineal approach is preferred for these patients because it involves less perioperative risk than an abdominal procedure, but the outcomes of this procedure in elderly patients are unknown. OBJECTIVE: The aim of this study was to examine whether clinical outcomes after perineal proctectomy are similar among elderly patients versus patients of younger age. DESIGN: This study was a retrospective review. SETTING: This study was conducted in mixed academic and private practice; the operations were performed at 16 hospitals. PATIENTS: Patients who had perineal proctectomy for rectal prolapse from 1994 to 2012 were grouped according to age: <70 (group A), 70 to 79 (group B), 80 to 89 (group C), and ≥90 years (group D). INTERVENTIONS: Perineal proctectomy with or without concurrent levatorplasty was performed. MAIN OUTCOME MEASURES: The primary outcomes measured were postoperative complications, recurrence, and survival after perineal proctectomy. RESULTS: Four hundred patients underwent 518 perineal proctectomies: group A, N = 113; group B, N = 113; group C, N = 208; and group D, N = 84. The immediate and late complication rates were 5.6% and 3.5% and did not vary by age. Recurrence was 22.6% and was significantly different between groups, with the lowest recurrence in group D, 14.3% (p = 0.007). Reoperation after recurrence was less likely in group D. The main type of reoperation was perineal proctectomy (41.5%), but, for group D, recurrence was usually managed nonoperatively (58.3%). Median survival after operation was more than 4 years in the advanced age group. LIMITATIONS: Retrospective data, which did not allow analysis of patients with rectal prolapse who did not undergo surgery, were used in this study. CONCLUSIONS: When selected appropriately, patients 90 years of age or older have outcomes similar to younger patients; therefore, age alone should not be a contraindication to surgery. In addition, elderly patients have a median survival of more than 4 years after surgery, so the operative risk can be worth the benefit accrued.

Comparison of carotid intima-media thickness in pediatric patients with metabolic syndrome, heterozygous familial hyperlipidemia and normals.

Background. Our goal was to compare the carotid intimal-medial thickness (CIMT) of untreated pediatric patients with metabolic syndrome (MS), heterozygous familial hyperlipidemia (heFH), and MS+heFH against one another and against a control group consisting of healthy, normal body habitus children. Methods. Our population consisted of untreated pediatric patients (ages 5-20 yrs) who had CIMT measured in a standardized manner. Results. Our population included 57 with MS, 23 with heFH, and 10 with MS+heFH. The control group consisted of 84 children of the same age range. Mean CIMT for the MS group was 469.8 µ m (SD = 67), 443.8 µ m (SD = 61) for the heFH group, 478.3 µ m (SD = 70) for the MS+heFH group, and 423.2 µ m (SD = 45) for the normal control group. Significance differences between groups occurred for heFH versus MS (P = 0.022), heFH versus control (P = 0.038), MS versus control (P = 9.0E - 10), and MS+heFH versus control (P = 0.003). Analysis showed significant negative correlation between HDL and CIMT (r = -0.32, P = 0.03) but not for LDL, triglycerides, BP, waist circumference, or BMI. Conclusion. For pediatric patients, the thickest CIMT occurred for patients with MS alone or for those with MS+heFH. This indicates that MS, rather than just elevated LDL, accounts for more rapid thickening of CIMT in this population.

A laboratory model of a prebiotic, spontaneous, and continuous enantiomeric enrichment process.

Construction and operation of a laboratory model, which combines the lately discovered enantioenrichment method of the author (2007) with the sun-powered evaporative pumping process of Hsu and Siegenthaler (Sedimentology 12:11-25 1969), is described. The model operated continuously for 120 days before it was intentionally shut down, even though it could have continued. During that time it raised the enantiomeric excess of the test material by a factor of 3.6. Implications of these results on the origin of biohomochirality are discussed.

Does ligation of the intersphincteric fistula tract raise the bar in fistula surgery?

BACKGROUND: The ligation of the intersphincteric fistula tract procedure has been reported to have high cure rates, with minimal impairment of continence. OBJECTIVE: The aim of this study was to evaluate the success rates and functional outcome after the ligation of the intersphincteric fistula tract procedure. DESIGN: This study was performed as a retrospective review. SETTINGS: The study was conducted at the Division of Colon and Rectal Surgery, University of Minnesota and at affiliated hospitals in Minneapolis and St. Paul, Minnesota, between March 2007 and September 2011. PATIENTS: Ninety-three patients with transsphincteric cryptoglandular anal fistula were included. INTERVENTIONS: Ligation of the intersphincteric fistula tract procedure was performed. MAIN OUTCOME MEASURES: Failure was defined as persistent or recurrent drainage, air leakage from a patent external opening, or intersphincteric incision or reoperation for recurrent fistula. Success was defined as healing of the external fistula opening and intersphincteric incision. Patients were followed up with a questionnaire to assess the recurrence rate and the Wexner incontinence score. RESULTS: The median follow-up time for was 19 months (range, 4-55). Thirty patients (32%) had a history of previous surgery for their fistula. The success rate of fistula healing was 40% after the first ligation of the intersphincteric fistula tract procedure. When including patients with repeat ligation of the intersphincteric fistula tract and subsequent intersphincteric fistulotomy after ligation of the intersphincteric fistula tract repair, the success rates were 47% and 57%. Patients with successful fistula closure reported a mean Cleveland Clinic Florida Fecal Incontinence score of 1.0 (SD 2.3). No predictor for successful fistula closure was found. LIMITATIONS: Retrospective design, limited accuracy of diagnosing fistula failure, and lack of baseline continence were limitations of this study. CONCLUSION: The present study indicates that the ligation of the intersphincteric fistula tract procedure for transsphincteric fistulas has a significant risk for failure but good functional outcome in patients with no recurrence.

Assessment of metformin as an additional treatment to therapeutic lifestyle changes in pediatric patients with metabolic syndrome.

Objective. To assess the effectiveness of metformin and therapeutic lifestyle changes (TLCs) in a clinical setting, compared to TLC alone in adolescents with metabolic syndrome (MS). Methodology. This study was a retrospective trial consisting of 60 patients, aged 8-18 years, who were treated for MS at an outpatient clinic. Two groups were formed: the metformin group (M group) and the control group (C group). The M group had been given metformin along with TLC, and the C group had been given TLC alone. Several outcome measures were obtained; the main outcome measure was measuring the change in percentile and z-score of weight and BMI. Results. There were no significant differences between the two groups at the conclusion of the study, except for height percentile (P = 0.02) and z-score (P = 0.03). Both groups showed promising significant intragroup decreases in weight z-score but BMI percentile and z-score were only significantly decreased in the M group. Conclusion. Metformin at an average dose of 1033 mg, when added to TLC, did not show any clinically important efficacy compared to TLC alone in a pediatric population with MS. However, both groups made significant changes in a positive direction, which may be solely due to TLC.

Sigmoidectomy syndrome? Patients' perspectives on the functional outcomes following surgery for diverticulitis.

BACKGROUND: Bowel function following surgery for diverticulitis has not previously been systematically described. OBJECTIVE: This study aimed to document the frequency, severity, and predictors of suboptimal bowel function in patients who have undergone sigmoid colectomy for diverticulitis. DESIGN: This study is a retrospective analysis. SETTING: This study was conducted at a large, academic medical center. PATIENTS: Three hundred twenty-five patients who underwent laparoscopic or open sigmoid colectomy with restoration of intestinal continuity for diverticulitis were included in the study population. Of these, 249 patients (76.6%) returned a 70-question survey incorporating the Fecal Incontinence Severity Index, the Fecal Incontinence Quality of Life Scale, and the Memorial Bowel Function Instrument. MAIN OUTCOME MEASURES: Survey responders and nonresponders were compared with the use of χ and t tests. Responders with suboptimal bowel function (fecal incontinence, urgency and/or incomplete emptying) were then compared with those with good outcomes by the use of logistic regression analysis to determine the predictors of poor function. RESULTS: Of the responders, 24.8% reported clinically relevant fecal incontinence (Fecal Incontinence Severity Index ≥ 24), 19.6% reported fecal urgency (Memorial Bowel Function Instrument Urgency Subscale ≥ 4), and 20.8% reported incomplete emptying (Memorial Bowel Function Instrument Emptying Subscale ≥ 4). On logistic regression analysis, fecal incontinence was predicted by female sex (OR = 2.3, p = 0.008) and the presence of a preoperative abscess (OR = 1.4, p < 0.05). Fecal urgency was associated with female sex (OR = 1.3, p < 0.05) and a diverting ileostomy (OR = 2.1, p < 0.001). Incomplete emptying was associated with female sex (OR = 1.4, p < 0.05) and postoperative sepsis (OR = 1.9, p < 0.05). LIMITATIONS: This study was limited by the fact that we did not use a nondiverticulitis control group and we had limited preoperative data on the history of bowel impairment symptoms. CONCLUSION: One-fifth of patients reported fecal urgency, fecal incontinence, or incomplete emptying after surgery for diverticulitis. Despite the limitations of our study, these results are concerning and should be investigated further prospectively.

[Sphincter preserving surgery for transsphincteric anal fistulas]. / Sfinkterbevarende kirurgi ved transsfinkteriske anale fistler.

The treatment of transsphincteric anal fistulas is a balance between the elimination of the sepsis and the functional outcome. In the last few decades sphincter preserving methods have been developed. Fibrin glue and the anal fistula plug are methods with excellent functional outcomes, but the success rates have decreased in recent years. The endorectal advancement flap is the gold standard with a high success rate, but with a risk of minor incontinence. The procedure of the ligation of the intersphincteric fistula tract is the latest option with excellent result so far. The tailored treatment with enhanced glues looks promising.

Ligation of the intersphincteric fistula tract: an effective new technique for complex fistulas.

INTRODUCTION: The management of complex fistulas is difficult. Maintaining continence while achieving durable fistula closure is the goal of surgical management. This study describes our experience with a novel sphincter-sparing technique called the ligation of the intersphincteric fistula tract, which involves ligation and division of the fistula tract in the intersphincteric space. METHODS: All patients from July 2007 to December 2008 with trans- or suprasphincteric fistula treated with the procedure were prospectively followed. Procedures were performed by surgeons with fellowship training in a referral center. Demographic data, comorbidities, previous repair attempts, and postoperative data were collected. RESULTS: A total of 39 patients underwent a ligation of the intersphincteric fistula tract during a 17-month period. Median age was 49 years. A total of 29 patients (74%) had previous attempts at repair, with a median of 2 failed repairs. Follow-up data were available in 90% (35 of 39). Median follow-up was 20 weeks. Successful fistula closure was achieved in 57% of the patients (20 of 35). Median time to failure was 10 weeks (range, 2-38 weeks). No patient reported any subjective decrease in continence after the procedure. CONCLUSION: Ligation of the intersphincteric fistula tract is a new sphincter-sparing procedure for complex transsphincteric fistula. The success rate is comparable with other sphincter-preserving techniques. Importantly, it appeared to effectively preserve continence. Adding safe, muscle-sparing surgical options to our armamentarium for dealing with transsphincteric fistula is essential. Additionally, the procedure is easy to learn and has very low cost. Long-term follow-up and randomized, controlled trials are necessary to assess efficacy and durability.

Treatment of complex anal fistulas with the collagen fistula plug.

PURPOSE: Anal fistulas that involve a significant amount of sphincter may be difficult to treat without compromising continence function. In this study, we evaluated our experience with the Surgisis anal fistula plug, which was recently reported to be successful in >80 percent of patients with complex fistulas. METHODS: We retrospectively collected patient and fistula characteristics, procedure details, and follow-up information for all patients treated with the anal fistula plug at our institution from January 2006 through April 2007. The outcome was considered successful if the external opening was closed and if the patient had no drainage at the last follow-up. Using multivariate statistics, we analyzed the relationship between anal fistula plug success and several key variables. RESULTS: From January 2006 through April 2007, 47 patients with 49 complex anal fistulas underwent 64 anal fistula plug procedures. The median follow-up time for patients who were considered healed was 6.5 (range, 3-11) months. The success rate was 31 percent per procedure and 43 percent per patient. An increased amount of external sphincter involvement was associated with a higher failure rate (P < 0.05). CONCLUSIONS: In our early experience with the anal fistula plug, 43 percent of patients with complex anal fistulas were successfully treated. Patients with less external sphincter involvement were more likely to heal.

Perianal Paget's disease treated with wide excision and gluteal skin flap reconstruction: report of a case and review of the literature.

BACKGROUND: Paget's disease of the anus is a rare perianal disorder. The condition is often associated with underlying invasive carcinoma and the prognosis is poor when underlying adenocarcinoma is present. METHODS: We report the case of a 72-year-old woman suffering from a two-year history of perianal itching, bleeding, and irritation. Perianal Paget's disease was confirmed by histopathologic demonstration of Paget's cells from a biopsy. Synchronous malignancy and metastasis were excluded. RESULTS: A first-stage operation consisted of a wide excisional biopsy with frozen section margin assessment. Permanent sections confirmed absence of invasive carcinoma and clear margins. Four days after wide excision, bilateral gluteal skin flap reconstruction was performed with a temporary diverting colostomy. No adjuvant therapy was necessary, and after one-year follow-up, the patient remains disease free. CONCLUSION: Perianal Paget's disease continues to pose problems in diagnosis and treatment. Our case report of perianal Paget's disease shows one method of management for advanced non invasive disease.

Mechanical/physical methods of cell disruption and tissue homogenization.

This chapter covers the various methods of mechanical cell disruption and tissue homogenization that are currently commercially available for processing minute samples (<1 ml) to larger production quantities. These mechanical methods of lysing do not introduce chemicals or enzymes to the system. However, the energies needed when using these "harsh" methods can be high and destroy the very proteins being sought. The destruction of cell membranes and walls is effected by subjecting the cells (1) to shearing by liquid flow, (2) to exploding by pressure differences between inside and outside of cell, (3) to collision forces by impact of beads or paddles, or (4) a combination of these forces. Practical suggestions to optimize each method, where to acquire such equipment, and links to reference sources are included.

Experimental evidence leading to an alternative explanation of why D-tyrosine sometimes crystallizes faster than its L-enantiomer.

On the occasions when D-tyrosine is observed to crystallize faster than its L-enantiomer, it is the result of a diastereomeric interaction between an airborne, non-racemic, chiral influence--probably a fungal spore--and the tyrosine enantiomers, enhancing the degree of crystal nucleation of D-tyrosine over L-tyrosine. This explanation, supported by experimental evidence, is presented as a more plausible alternative to the Shinitzky-Deamer hypothesis (Shinitzky et al., Progress in biological chirality, Elsevier, Amsterdam, pp. 329-337, 2004; Deamer et al., Chirality, 19:751-763, 2007) which relies on the parity violation energy difference between enantiomers, a femtojoule to picojoule per mole theoretical energy range.

A pilot study in the efficacy and safety of gemfibrozil in a pediatric population.

BACKGROUND: Gemfibrozil reduces plasma triglycerides and raises high-density lipoprotein cholesterol (HDL-C) in adults and also reduces the incidence of cardiovascular endpoints in adults. Its efficacy in improving lipid abnormalities has not been evaluated in children. OBJECTIVE: Our purpose was to investigate whether gemfibrozil would lower triglycerides and raise HDL-C with minimal adverse effects in a pediatric population with metabolic syndrome. METHODS: We conducted a retrospective study of 47 pediatric patients with metabolic syndrome who started gemfibrozil treatment, 1200 mg/day because of failure or lack of interest in therapeutic lifestyle changes. Eligibility required patients to be younger than 21 years of age, and have pretreatment and on-treatment fasting lipid profiles. Data recorded included age at start of treatment, blood pressure, body mass index, waist circumference, percent body fat, total plasma cholesterol, HDL, low-density lipoprotein, triglycerides, alanine aminotransferase, and aspartate aminotransferase. Treatment duration was elapsed time between starting gemfibrozil and the last clinic visit. RESULTS: Average age of the study cohort was 14 years and mean duration on medication was 249 days. Those patients who had pretreatment and on-treatment plasma lipid data (33 of 47) were included in an analysis for efficacy. All 47 patients were monitored for safety. Mean triglycerides decreased by 57%: 426 (standard error of mean = 33.6) to 184 mg/dL (standard error of mean = 19) (P < 0.0001). Mean HDL increased by 20%: 35 to 42 mg/dL (P < 0.001). Body composition changes were insignificant, indicating that the lipid changes can be attributed to gemfibrozil. Two of forty-seven patients reported muscle pain from the drug, one of whom was considered to have had a possible adverse effect from the medication as indicated by muscle pain. CONCLUSION: Gemfibrozil significantly lowers triglycerides and raises HDL with reasonable safety in a pediatric population with metabolic syndrome.

Dartos muscle interposition flap for the treatment of rectourethral fistulas.

PURPOSE: Rectourethral fistula is a rare complication of pelvic surgery, trauma, or inflammation. The many techniques for repairing these fistulas vary in their success rates. Our goal was to describe the use of a dartos muscle interposition flap for repair of these fistulas. METHODS: We performed a retrospective review of eight patients who underwent repair of a rectourethral fistula with a dartos muscle interposition flap. We describe the success rate and patient-related factors that may have affected success. The technique of dartos muscle interposition is described and compared with other previously described techniques. RESULTS: Six of eight patients had healing of their fistulas documented by follow-up cystogram. CONCLUSIONS: Dartos muscle interposition is a straightforward technique that can result in successful fistula repair but should not be used in patients with risk factors for poor wound healing, such as an immunocompromised state or previous radiation therapy.

Does infliximab infusion impact results of operative treatment for Crohn's perianal fistulas?

PURPOSE: Infliximab is an effective treatment for active intestinal Crohn's disease; however, the efficacy of infliximab in perianal Crohn's disease is controversial. This study was designed to compare patients with Crohn's disease who underwent perianal fistula surgery with or without infliximab infusion. METHODS: A retrospective chart review of 226 consecutive patients with Crohn's disease who underwent operative treatment with or without infliximab (3-6 infusions of 5 mg/kg) from March 1991 through December 2005 was completed. Patients were classified as completely healed, minimally symptomatic (seton placement with minimal drainage and/or infliximab dependence), and failure (persistent or recurrent symptomatic fistula, diverting procedure, or proctectomy). RESULTS: A total of 226 patients underwent operative treatment alone (n = 147) or in combination with infliximab infusion (n = 79). Age, gender, and preoperative history of intestinal and perianal Crohn's disease were similar between groups. Mean follow-up was 30 (range, 6-216) months. Operative treatment consisted of seton drainage (n = 112), conventional fistulotomy (n = 92), fibrin glue injection (n = 14), advancement flap (n = 5), collagen plug insertion (n = 2), and transperineal repair (n = 1). Eighty-eight patients (60 percent) healed completely with operative treatment alone, and 47 patients (59 percent) healed after operative treatment in combination with infliximab (P = not significant). CONCLUSIONS: Operative treatment of perianal fistulas in patients with Crohn's disease resulted in complete healing in approximately 60 percent of patients. Preoperative infliximab infusion did not affect overall healing rates.