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PURPOSE: The purpose of this study was to identify predictive factors for postoperative surgical site infections (SSIs), and increased length of hospital stay (LOS) after ventral/incisional hernia repair (VIHR) using multi-center, prospectively collected data. STUDY DESIGN: Cases of VIHR from 2009 to 2010 were identified in the American College of Surgeons National Surgical Quality Improvement Program database. Using logistic regression, a prediction model utilizing 41 variables was developed to identify risk factors for postoperative SSIs, and increased LOS. Separate analyses were carried out for reducible and incarcerated/strangulated cases. RESULTS: A total of 28,269 cases of VIHR were identified, 25,172 of which met inclusion criteria. 18,263 cases were reducible hernias, and 6,909 cases were incarcerated/strangulated hernias. Our prediction model demonstrated that body mass index ≥30 kg/m(2), smoking, American Society of Anesthesiology (ASA) class 3, open surgical approach, prolonged operative times, and inpatient admission following VIHR were significant predictors of postoperative SSIs. In addition, risk factors associated with prolonged LOS included older age, African American ethnicity, history of alcohol abuse, ASA classes 3 and 4, poor functional status, operation within the last 30 days of the index operation, history of chronic obstructive pulmonary disease, congestive heart failure, and bleeding disorder, as well as open surgical approach, non-involvement of residents, prolonged operative times, recurrent hernia, emergency operation, and low preoperative serum albumin level. CONCLUSIONS: Obesity and smoking are modifiable risk factors for SSIs after VIHR, whereas a low serum albumin level is a modifiable risk factor for prolonged LOS. Addressing factors preoperatively might improve patient outcome, and reduce health care expenditures associated with VIHR. In addition, if feasible, the laparoscopic approach should be strongly considered.

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Mosquito larvae face numerous biotic and abiotic challenges that affect their development and survivorship, as well as adult fitness. We conducted two experiments under semi-natural conditions to evaluate the effects of intraspecific competition, nutrient limitation and sub-lethal doses of malathion on individual life history traits in adult Culex pipiens (Diptera: Culicidae). In the first experiment, larvae of Cx. pipiens were reared at different intraspecific densities and exposed to sub-lethal doses of malathion. In the second experiment, different intraspecific densities of Cx. pipiens larvae were reared under conditions of low or high larval nutrients, and subsequent adults were fed on either water or 10% sucrose solution. Malathion treatment had relatively minor effects compared with density, which had significant negative effects on development rate, survivorship to adulthood, body size (wing length) and longevity. As larval density increased, a sex ratio distortion in survivorship to adulthood emerged, in which a bias towards males was apparent. Nutrient-rich larval environments alleviated, in part, the effects of increasing density and extended the lifespan of mosquitoes fed on water and 10% sucrose. Density-dependent alterations in adult longevity attributable to the larval environment are complex and show contrasting results depending on interactions with other environmental factors. This study suggests that larval resource availability and competition influence Cx. pipiens population growth correlates and have lasting effects on traits that relate to a mosquito's ability to vector pathogens.

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The introduction of Aedes albopictus (Skuse) in the United States has been associated with declines in abundance of resident mosquito species, presumably because of resource competition, as larvae of Ae. albopictus have been illustrated as superior competitors under certain resource conditions. We evaluated the hypothesis that varying the type and ratio of two food resources (Foxtail grass: American elm) alters the competitive outcome of Ae. albopictus and Culex pipiens (L.). We measured survivorship, development time, size, and adult longevity, and estimated the population growth index (A') of populations raised both alone and in equal number with the interspecific competitor, across five ratios of the two food resources. Competition was asymmetric with Ae. albopictus, the superior competitor across all resource treatments; however, the competitive advantage Ae. albopictus had over Cx. pipiens was reduced as grass became the predominant resource. With elm as the predominant resource, the population growth index (A') for both Ae. albopictus and Cx. pipiens was lower in intraspecific and interspecific competition treatments, respectively. The treatments also impacted adult life history, as life spans of both Ae. albopictus and Cx. pipiens varied when they emerged from larval conditions with different resource and competition treatments. We discuss the possible differences in the two species' efficiencies in exploiting the two resource types. Despite some resource conditions alleviating the competitive effects of Ae. albopictus on Cx. pipiens, competition remained asymmetric; thus, additional mechanisms are likely operating under field conditions when the two species coexist.

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Pool testing of vector samples for arboviruses is widely used in surveillance programmes. The proportion of infected mosquitoes (Diptera: Culicidae) is often estimated from the minimum infection rate (MIR), based on the assumption of only one infected mosquito per positive pool. This assumption becomes problematic when pool size is large and/or infection rate is high. By relaxing this constraint, maximum likelihood estimation (MLE) is more useful for a wide range of infection levels that may be encountered in the field. We demonstrate the difference between these two estimation approaches using West Nile virus (WNV) surveillance data from vectors collected by gravid traps in Chicago during 2002. MLE of infection rates of Culex mosquitoes was as high as 60 per 1000 at the peak of transmission in August, whereas MIR was less than 30 per 1000. More importantly, we demonstrate roles of various pooling strategies for better estimation of infection rates based on simulation studies with hypothetical mosquito samples of 18 pools. Variable size pooling (with a serial pool sizes of 5, 10, 20, 30, 40 and 50 individuals) performed consistently better than a constant size pooling of 50 individuals. We conclude that variable pool size coupled with MLE is critical for accurate estimates of mosquito infection rates in WNV epidemic seasons.

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Radial artery harvesting for coronary revascularization may result in digit ischemia if collateral circulation is inadequate. The purpose of this study was to compare changes in ulnar artery flow velocity during radial artery compression (RAC) with changes in first- and second-digit pressures during RAC, a previously validated predictor of digital ischemia. Photoplethysmography was used to measure first- and second-digit arterial pressures before and during RAC on 80 extremities. Color flow duplex imaging was used to measure distal ulnar artery peak systolic velocity before and during RAC. Seventy-eight of eighty extremities had a slight increase in ulnar artery velocity with RAC. There was no correlation between ulnar artery velocity changes and digit pressure changes. Measurement of ulnar artery velocity during RAC is not a useful predictor of digit pressure changes. Measurement of segmental upper extremity pressures with first- and second-digit pressure measurement during radial artery compression should remain the preferred preoperative screening tool for radial artery harvest prior to CABG.

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The late Professor R.L. Metcalf is being honored as one of the leading entomologists of the 20th century, whose worldwide influence on entomology, insecticide and environmental toxicology, and insect chemical ecology was enormous. His 82-year life span mirrored the transition in entomology from the early descriptive phase of insect and plant and animal interactions to the more detailed integration of the biochemical, physiological, behavioral, ecological, and environmental understanding of nature within the context of societal issues and needs. New techniques, some relatively simple but never-the-less ingenious, paved his way to fame. Metcalf was an enormously productive scientist. His 450+ research publications, numerous books and editorships, patents, internationally oriented staff of students, postdocs and associates, and his contributions to teaching and to public service let him stand out as a challenging role model for those young minds starting their careers at the beginning of the 21st century.

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Inferior vena cava (IVC) aneurysms are extremely rare, with only 18 reported cases in the world literature. These aneurysms are categorized as acquired, congenital, or associated with arteriovenous fistulae. Thrombosis of an IVC aneurysm can lead to IVC syndrome characterized by massive lower extremity edema, pulmonary embolism, or even death. Therapeutic alternatives range from watchful waiting to operative resection. This report presents a case of an IVC aneurysm noted incidentally at the time of diagnostic computed tomography for the evaluation of blunt chest trauma following a motor vehicle collision. In addition, the classification, embryology, diagnosis, and management of this unusual clinical entity are reviewed.

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Acute symptomatic upper extremity deep vein thrombosis (DVT) are estimated to account for only 2-4% of all deep vein thrombosis. Upper extremity DVT leading to phlegmasia cerulea dolens (PCD) occurs in an estimated 2-5% of these cases. Progression of PCD to venous gangrene is extremely rare with only 16 previously reported cases in the literature. Only 7 of the cited cases document significant tissue loss. This report describes a 61-year-old male who developed upper extremity DVT complicated by PCD which led to venous gangrene and limb loss.

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The activity of phospholipase A2 (PLA2) is elevated in the intestinal epithelia of patients with inflammatory bowel disease (IBD). We recently reported that PLA2 mediates hydrolysis of phosphatidylcholine (PC) to lysophosphatidylcholine (L-PC) when both are applied to the apical surface of cultured EC monolayers, resulting in increased bacterial translocation (BT) and decreased transepithelial electrical resistance (TEER). Free fatty acids (FFA) are the other products of this reaction, however, their effect on Caco-2 cell permeability has not been reported. In addition to PC, other luminal phospholipids are present at the surface of the enterocyte. PLA2 may also mediate the hydrolysis of luminal phospholipids other than PC. The aim of this study was to examine the effects of phospholipids other than PC and common FFA on intestinal epithelial permeability and BT. Human Caco-2 enterocytes were grown to confluence on porous filters in the apical chamber of a two-chamber cell-culture system. Monolayer integrity and tight-junction permeability were measured as TEER. First, common FFA released by PC hydrolysis were determined using thin-layer chromatography (TLC). In separate experiments, monolayers were treated with phosphatidylethanolamine (PE), lysophosphatidylethanolamine (L-PE), or palmitoleic acid, oleic acids, linoleic acids, and arachidonic acid solubilized in solution with PC. The magnitude of BT was determined 2 h after treatment by adding Escherichia coli C25 to the apical chamber followed by quantitatively culturing basal-chamber samples. Statistical analysis was by the Kurosaki-Wallis test. TLC of PC samples incubated with PLA2 on the apical surface of Caco-2 monolayers demonstrated the production of palmitoleic acid, oleic acids, linoleic acids, and arachidonic acid. L-PE significantly decreased TEER compared to controls, but to a lesser degree than L-PC alone. L-PE had no effects on BT. Palmitoleic acid and oleic acid likewise significantly decreased TEER compared to controls, however, less than L-PC. All FFA tested had no effect on BT. Phospholipids applied to the apical surface of enterocytes, such as those found in vivo in mucus, can be hydrolyzed by the enzyme PLA2 resulting in lysophospholipid and FFA species that can alter enterocyte monolayer permeability. However, FFA and L-PL, other than L-PC, appear to have no effect to stimulate BT. This observation may have clinical implications in the pathogenesis and treatment strategies for IBD patients in whom enterocyte PLA2 activity has been shown to be elevated.

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We present the case of a woman who had coagulopathy and sepsis and who developed compartment syndrome of the arm. We discuss recognition and treatment of arm compartment syndrome and review the literature regarding this condition.

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Sarcoidosis involving the pancreas is rare. Patients can present with symptoms that mimic pancreatic cancer. We report a case of a male patient with clinical and radiographic findings suggestive of pancreatic cancer as the initial manifestation of sarcoidosis.

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The aim of this study was to determine current management practices of physicians caring for patients with perianal Bowen's disease. A questionnaire was sent to 1,499 members listed in the 1997 American Society of Colon and Rectal Surgeons Directory asking them how many patients they have treated and which operative or nonoperative treatment option they choose for small (< or =3 cm), large (> 3 cm), and microscopic lesions. Of 1,499, 663 (44.2%) surgeons responded. Not all respondents answered each item. Seventy-five per cent of surgeons surveyed (n = 653) devote greater than 75 per cent of their practice to colon and rectal surgery. Of 642 respondents, 552 (86%) managed a total of <10 patients, and 90/642 (14%), > or =10 patients. Ninety-six per cent of respondents use wide local excision for patients with small lesions. Eighty-seven per cent of respondents use wide local excision for patients with large lesions. Seventy-four per cent treat patients with microscopic disease conservatively and without wide excision. The majority of surgeons caring for patients with perianal Bowen's disease are performing wide local excision for both small and large lesions. Microscopic disease was usually treated conservatively with observation alone.

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We evaluated the efficacy of commercial antimosquito products in field trials in Illinois in June 1998 by comparing mosquito landing rates. Products tested were a sonic mosquito repeller, an insect killing grid using ultraviolet light and 1-octen-3-ol as lures, mosquito smoke coils containing a pyrethroid, citronella candles, the mosquito plant Pelargonium citrosum, and a N,N-diethyl-3-methylbenzamide (deet)-impregnated wrist band. The sonic mosquito repeller, insect killing grid, and mosquito smoke coils were evaluated in 16 trials over 5 days; the citronella candles and mosquito plants in II trials over 4 days; and the wrist bands in 4 trials on 1 day. In all 3 studies, we compared landing rates with the antimosquito products to both positive (topical application of a deet formulation) and negative (no treatment) controls. The deet topical repellent had a consistently lower landing rate than all the nontopically applied products tested. However, the mosquito coils and the deet-impregnated wrist bands did significantly reduce mosquito landing rates relative to untreated controls.

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The larvicidal toxicities of methylated soy oil (MSO) and surfactant combinations were compared to 2 commercially available oil larvicides (Golden Bear Oil 1111 and Bonide) in standard laboratory bioassays of 4th-stage larvae of Culex pipiens Linn. The dose lethal to 50% of the test organisms (LD50) and the dose lethal to 95% of the test organisms (LD95) values are presented as microliters (microl) per beaker (treatment surface area of 54 cm2). The 2 surfactant-MSO mixtures differed significantly in their toxicity to Cx. pipiens larvae; 2% Pyroter CPI-40 in MSO was more toxic than 2% Pluronic L121 in MSO (LD50 = 3.8 microl per 54 cm2 and 11.3 microl per 54 cm2, respectively). The 2 most active larvicides were Golden Bear Oil (LD50 = 3.6 microl per 54 cm2) and the 2% Pyroter-MSO mixture. These 2 were not significantly different from each other. Bonide (LD50 = 6.2 microl per 54 cm2) and the Pluronic L121-MSO mixture (LD50 = 11.3 microl per 54 cm2) were less toxic than Golden Bear Oil and the MSO-Pryroter mixture and they were significantly different from each other. Bioassays with 4th-stage larvae of Anopheles stephensi Liston showed that toxicity of the Pyroter-MSO formulations increased about 2-fold from 18 degrees C to 24 degrees C (LD50 = 20.5 microl per 54 cm2 and 11.8 microl per 54 cm2, respectively). The laboratory bioassays suggest that MSO mixed with surfactants are potential mosquito larvicides. We also evaluated the influence of the 2 surfactants on the toxicity of 3 monoterpenes. The larvicidal activity of citral and limonene increased with the addition of surfactants, but neither surfactant enhanced the toxicity of cineole. All 3 monoterpenes, with and without surfactants, were considered poor candidates as surface larvicides because of their high volatilities.

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Patients with an implantable cardioverter defibrillator (ICD) often refrain from physical exercise for fear of precipitating a life-threatening arrhythmia or receiving an ICD shock. However, most of these patients are able to safely exercise if they are provided appropriate clinical guidelines. This review describes the factors that enter into the development of an exercise program for patients with an ICD.

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The contents of the Brindley's gland of Triatoma lecticularia (Stål) (Heteroptera: Reduviidae: Triatominae) have been identified by gas chromatography-mass spectrometry as isobutyric acid. This compound is found in similar secretions from certain other members of the Triatominae, and is suggested to play a role as a defensive pheromone and for intraspecies communication.

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The efficacy of formulations containing methylated soybean oil (MSO) alone and with technical-grade Bacillus thuringiensis var. israelensis (Bti) were compared to Golden Bear Oil (GB-1111) and a water-based Bti formulation against 3rd- to 4th-stage Anopheles quadrimaculatus larvae confined to sentinel cages in small rice plots. Three replicates each of MSO with 2% Pyroter added as a surfactant (MSO + PYR), MSO with 2% Pyroter and 4 g of Bti technical powder (MSO + PYR + Bti), GB-1111, a water-based formulation with 4 g of Bti technical powder (Bti + water), and untreated controls were performed. Mosquito larvae were introduced on the 1st day of treatment and at 4 days posttreatment. Mortality was recorded at 24 and 48 h posttreatment for the 1st installation and at 5 days posttreatment for the 2nd installation. The Bti + water formulation provided 71% control and the MSO + PYR + Bti formulation achieved 64% control, whereas MSO + PYR and GB-1111 produced 16 and 18% control, respectively, at 24 h posttreatment. With the exception of MSO + PYR + Bti, which decreased by 2%, the mean percent control increased slightly at 48h posttreatment across remaining treatments, with Bti + water obtaining 72% control. This was significantly higher than GB-1111, which achieved 23% control at 48 h posttreatment. The MSO + PYR and MSO + PYR + Bti formulations yielded 56 and 62% control, respectively, during the same interval and were not significantly different from one another. Formulations containing MSO + PYR exhibited delayed activity similar to GB-1111, with all formulations except MSO + PYR + Bti providing greatest control at 48 h posttreatment. Both MSO formulations (MSO + PYR + Bti and MSO + PYR) were statistically comparable to Bti + water and GB-1111, respectively, at 24 and 48 h posttreatment. None of the formulations exhibited a residual activity adequate enough to control An. quadrimaculatus larvae for up to 5 days.

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PURPOSE: The aim of this study was to review the literature with regard to perianal Bowen's disease and anal intraepithelial neoplasia. METHODS: A literature review was conducted from 1960 to 1999 using MEDLINE. RESULTS: Perianal Bowen's disease and anal intraepithelial neoplasia are precursors to squamous carcinoma of the anus. They are analogous to and are associated with cervical and vulvar intraepithelial neoplasia, and have human papillomavirus as a common cause. Biopsy and histopathologic examination is required for diagnosis and to distinguish other perianal dermatoses. Treatment options range from aggressive wide local excision of all disease with negative margins to observation alone for microscopic lesions not visible to the naked eye. The disease has a proclivity for recurrence and recalcitrance. CONCLUSIONS: Most surgeons caring for patients with perianal Bowen's disease and high-grade anal epithelial neoplasia use wide local excision, with an effort to obtain disease-free margins. Some authors have reported the advantages of ablative procedures such as laser ablation and cryotherapy. Microscopic disease found serendipitously in hemorrhoidectomy specimens can probably be treated conservatively with serial examinations alone. There is a lack of controlled data supporting an optimal treatment strategy. A multicenter controlled study comparing wide local excision with ablative procedures may be warranted.

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OBJECTIVE: Radial artery harvesting for coronary artery bypass may lead to digit ischemia if collateral hand circulation is inadequate. The modified Allen's test is the most common preoperative screening test used. Unfortunately, this test has high false-positive and false-negative rates. The purpose of this study was to compare the results of a modified Allen's test with digit pressure change during radial artery compression for assessing collateral circulation before radial artery harvest. METHODS: One hundred twenty-nine consecutive patients were studied before coronary artery bypass operations. A modified Allen's test was performed with Doppler ultrasound to assess blood flow in the superficial palmar arch before and during radial artery compression. A decreased audible Doppler signal after radial artery compression was considered a positive modified Allen's test. First and second digit pressures were measured before and during radial artery compression. A decrease in digit pressure of 40 mm Hg or more (digit DeltaP) with radial artery compression was considered positive. RESULTS: Seven of 14 dominant extremities (50%) and 8 of the 16 nondominant extremities (50%) with a positive modified Allen's test had a digit DeltaP of less than 40 mm Hg (false positive). Sixteen of 115 dominant extremities (14%) and 5 of 112 nondominant extremities (4%) with a negative Allen's test had a digit DeltaP of 40 mm Hg or more with radial artery compression (false negative). CONCLUSION: Use of the modified Allen's test for screening before radial artery harvest may unnecessarily exclude some patients from use of this conduit and may also place a number of patients at risk for digit ischemia from such harvest. Direct digit pressure measurement is a simple, objective method that may more precisely select patients for radial artery harvest. Additional studies are needed to define objective digital pressure criteria that will accurately predict patients at risk for hand ischemia after radial harvest.

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