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Previous studies have demonstrated that tumor necrosis factor-α (TNF-α) production from adipose tissue is elevated in obese animal models and in obese humans. It plays an important role in the induction of insulin resistance in experimental animals. In this study, we examined hypothalamic tissue expression of TNF-α and its receptors and TNF-α expression of adipose tissue in lean C57BLKSJ+/+ and obese polygenic New Zealand obese (NZO) mice. Obese animals exhibited hyperglycemia, hyperinsulinemia, hypertriglyceridemia, and hypercholesterinemia. Using RT-PCR, we observed increased expression (2.4-fold) of TNF receptor 2 (p75) in the hypothalamus of obese mice. TNF-α expression in adipose tissue of obese mice was eight times higher than in controls. TNF-α and TNF receptor 1 (p55) expression in hypothalamic tissue was similar in obese and lean animals. These results suggest that the hypothalamic TNF receptor 2 (p75) might play a role in obesity by modulating the actions of TNF-α in conditions of leptin resistance.

To meet the future goals of reduced emissions produced by gas turbine combustors, a better understanding of the process of formation of various pollutants is required. Both empirical and analytical approaches are used to provide the exhaust concentrations of pollutants of interest such as NOx, CO, and unburned hydrocarbon with varying degrees of success. In the present investigation, an emission model that simulates the combustor by a number of reactors representing various combustion zones is proposed. A detailed chemical kinetic scheme was used to provide a fundamental basis for the derivation of a number of expressions that simulate the reaction scheme. The model addresses the combined effects of spray evaporation and mixing in the reaction zone. The model validation included the utilization of a large data base obtained for an annular combustor of a modern turbopropulsion engine. In addition to the satisfactory agreement with the measurements, the model provided insight into the regions within the combustor that could be responsible for the excessive formation of emissions. Methods to reduce the emissions may be implemented in light of such information.

An emission model that combines the analytical capabilities of three-dimensional combustor performance codes with mathematical expressions based on detailed chemical kinetic scheme is formulated. The expressions provide the trends of formation and/or the consumption of Nox, CO, and UHC in various regions of the combustor utilizing the details of the flow and combustion characteristics given by the three-dimensional analysis. By this means, the optimization of the combustor design to minimize pollutant formation and maintain satisfactory stability and performance could be achieved. The developed model was used to calculate the emissions produced by several engine combustors that varied significantly in design and concept, and operated on both conventional and high-density fuels. The calculated emissions agreed well with the measurements. The model also provided insight into the regions in the combustor where excessive emissions were formed, and helped to understand the influence of the combustor details and air admissions arrangement on reaction rates and pollutant concentrations.

BackgroundThe classical treatment of perforated sigmoid diverticulitis with generalised peritonitis is based on the principle of two-stage surgical procedures with a temporary initial defunctioning colostomy. This approach is associated with significant morbidity, concerning mainly the abdominal wall.Patients and methodsTen consecutive patients, eight female and two male, with a mean age of 54.6 years, underwent an emergency laparoscopy for generalised peritonitis secondary to perforated diverticula. Six had had previous infectious episodes; six were obese; four were diabetic and two had chronic lung disease. After exploration of the abdominal cavity and discovery of a purulent peritonitis (n = 8) or faecal peritonitis (n = 2), an extensive peritoneal lavage was performed (average 15 litres), the contaminating sigmoid lesion was covered with biological glue and a drain inserted at the site of the lesion. In some cases, drainage of dependent zones was also performed. No colostomies were performed. Antibiotic therapy instituted as soon as the diagnosis had been made was continued, on average, for 7 days.ResultsThere was no mortality. There was a low morbidity: one case of lymphangitis on catheter and one of broncho-pulmonary infection. No cases of abdominal wall sepsis or residual deep collections were observed. The mean duration of hospitalisation was 8 days. Nine patients underwent a sigmoid resection (laparoscopic in eight cases) 3 to 4 months later, with a mean duration of hospitalisation of 6 days. One conversion to laparotomy was necessary.ConclusionsLaparoscopic treatment of generalised peritonitis secondary to perforated sigmoid diverticulitis constitutes an alternative to classical surgery. It is associated with a decreased morbidity and a marked reduction in duration of the hospitalisation. Colostomy can be avoided and the patient's quality of life is improved during the period previous to secondary colectomy, performed by laparoscopy eight times out of nine. In addition, the cost of this approach is significantly lower.

SHV-5 (pI 8.2), a novel broad-spectrum beta-lactamase encoded by a ca. 150-kilobase plasmid, was found in Klebsiella pneumoniae 160. SHV-5 beta-lactamase caused decreased susceptibility to most penicillins, cephalosporins, and monobactams, except imipenem and compounds which have a C6 or C7 alpha-methoxy substituent. beta-Lactamase inhibitors (clavulanic acid, sulbactam, and tazobactam) inhibited its activity and showed a synergistic effect when associated with different hydrolyzable beta-lactam compounds. Hybridization studies suggested that this enzyme may be related to, or derived from, the SHV enzyme. Increased MICs of cephamycins and temocillin associated with a decreased synergistic effect of the inhibitors on K. pneumoniae 160 might be linked to a decrease in two outer membrane proteins.

To enhance gas turbine combustor performance and emissions characteristics, better design methods need to be developed. In the present investigation, an emission model that simulates a detailed chemical kinetic scheme has been developed to provide the rate of reactions of the parent fuel, an intermediate hydrocarbon compound, CO, and H2. The intermediate fuel has variable carbon and hydrogen contents depending on operating conditions, that were selected in the development effort to simulate actual operation of rich/lean, diffusion flame, and lean combustor concepts. The developed reaction rate expressions address also the limited reaction rates that may occur in the near-wall regions of the combustor due to the admittance of radial air jets and cooling air in these regions. The validation effort included the application of the developed model to a combustor simulated by a multiple-reactor arrangement. The results indicate the accurate duplication of the calculations obtained from the detailed kinetic scheme using the developed model. This illustrates the great potential of using such a unified approach to guide the design of various types of combustor to meet the more stringent approach to guide the design of various types of combustor to meet the more stringent emissions and performance requirements of next-generation gas turbine engines.

BackgroundWhen splenic trauma does not require an emergency splenectomy in order to achieve hemostasis, the current policy is either observation under close surveillance, with transfusions if necessary, or conservative surgical procedure through laparotomy. Videolaparoscopic approach has the advantage of achieving in the same procedure, complete evacuation of the hemoperitoneum, full investigation of the abdominal cavity and repair of the damaged spleen.Patients and methodsOver a 4-year period, five patients aged 27.3 years on average, with severe splenic trauma but no major hemodynamic disturbance, were operated on by emergency laparoscopy. The diagnosis of splenic lesion had been confirmed preoperatively by ultrasonography. The procedure performed by open laparoscopy included evacuation of the hemoperitoneum and blood clots and splenic hemostasis which was achieved by the use of electrocoagulation and biological glue, associated in three cases with omentoplasty. Drains were inserted systematically.ResultsThe average length of operation was 75 min. There were no cases of conversion, nor mortality, nor morbidity. The average duration of hosprtalization was 10 days. No blood transfusions were required. A CT-scan was performed immediately in the postoperative course and served as the baseline for comparison during the follow-up. There were no reinterventions. The longest follow-up was 4 years and the mean follow-up 2.5 years. Laboratory tests or isotopic imaging did not detect any change in splenic function.ConclusionIn specific defined circumstances, videolaparoscopic repair of splenic trauma is justified provided that careful attention is paid to the patient's condition.

Beside the phenolic and quinone groups present in lignin which may affect retardation of the polymerization reactions of some vinyl monomers, the lignin network structure, the monomer configuration and the residual carbohydrate attached to lignin were found to play an important role. Die im Lignin vorhandenen Phenol‐ und Chinongruppen können bei einigen Vinylmonomeren eine Retardation der Polymerisationsreaktion bewirken. Es wurde gefunden, daß darüberhinaus auch die Netzstruktur des Lignins, die Konfiguration der Monomere und der Kohlenwasserstoffrest am Lignin eine wesentliche Rolle bei der Inhibierung spielen.

In order to formulate a common approach that could provide the spray parameters of airblast atomizers, various processes of liquid preparation, breakup, and secondary atomization have been included in a semi-analytical calculation procedure. The air velocity components in the atomizer flow field are provided by mathematical expressions, and the spray droplets are considered to form at ligament breakup through a disturbance wave growth concept. The validation of the developed approach included the application to six atomizers that significantly varied in concept, design, and size. They represented both prefilming and plain-jet types, and the data utilized in the present effort were obtained with six different liquids. Satisfactory agreement between the measurements and the predictions has been achieved under wide ranges of air/fuel ratio and air pressure drop for various test liquids. The results of this investigation indicate the potential of using such an approach in the early phases of airblast atomizer design, and may be followed by more detailed calculations using analytical tools.

The effects of air and liquid properties and atomizer dimensions on the spray characteristics of plain-jet airblast atomizers are examined. Mean drop size and drop-size distribution are measured using an improved form of light scattering technique. The test range includes wide variations in air velocity, air pressure, air/liquid ratio, and liquid viscosity. The experimental data generally confirm the results of previous studies on prefilming types of airblast atomizers. They show that increases in air velocity, air pressure, and air/liquid ratio all tend to produce a more uniform spray and a lower mean drop size. It is also observed that any change in air properties, liquid properties, and atomizer geometry that lowers the mean drop size also produces a more uniform distribution of drop sizes in the spray.

Although Toxoplasma gondii multiplies within normal murine alveolar and peritoneal macrophages, it is killed by normal rat alveolar and peritoneal macrophages. The killing by rat macrophages is by a nonoxidative mechanism. Studies on normal human alveolar macrophages have reported disparate results in regard to their ability to inhibit or kill T. gondii. We considered it of interest to explore further the effect of normal human alveolar and peritoneal macrophages on T. gondii. Unstimulated alveolar macrophages from each of seven individuals demonstrated a marked ability to kill or inhibit multiplication of T. gondii in vitro (e.g., the number of parasites per 100 alveolar macrophages was 31 at time zero and 2 at 18 h, whereas this value increased from 37 at time zero to 183 at 18 h in murine macrophages assayed in parallel). In quantitative assays of superoxide, alveolar macrophages released a substantial amount of superoxide when exposed to phorbol myristate acetate or to candidae. In contrast, alveolar macrophages incubated with T. gondii released no more superoxide than when in medium alone. Scavengers of superoxide anions, hydrogen peroxide, singlet oxygen, and hydroxyl radicals failed to inhibit killing of T. gondii by alveolar macrophages. Peritoneal macrophages from each of six normal women undergoing laparoscopy killed T. gondii in vitro; results of quantitative superoxide assays and scavenger experiments demonstrated that no oxidative burst was triggered in these macrophages by exposure to T. gondii. These data indicate that normal human alveolar and peritoneal macrophages can kill an intracellular parasite by nonoxidative mechanisms and suggest that these mechanisms are important in inhibition or killing of other opportunistic intracellular pathogens.

Summary: In a prospective randomized trial comparing a totally pre-peritoneal (TPP) laparoscopic approach and the Stoppa procedure (open), 100 patients with inguinal hernias (Nyhus IIIA, IIIB, IV) were followed over a 3-year period. Both groups were epidemiologically comparable. In the laparoscopic group, operating time was significantly longer (p=0.01) but hospital stay (3.2 vs 7.3 days) and delay in return to work (17 vs 35 days) were significantly reduced (p=0.01). Post operative comfort (less pain) was better (p=0.001) after laparoscopy. In this group, morbidity was also reduced (4% vs 20%, p=0.02). The mean follow up was 605 days and 93% of the patients were reviewed at three years. There were three (6%) recurrences after TPP, especially at the beginning of the surgeon's learning curve versus one for the Stoppa procedure (ns). For bilateral hernias, the authors suggest the use of a large prosthesis rather than two small ones to minimise the likelihood of recurrence. In the conditions described the laparoscopic (TPP) approach to inguinal hernia treatment appears to have the same long-term recurrence rate as the open (Stoppa) procedure, but confers a real advantage in the early post operative period.

The influence of initial liquid film thickness on mean drop size and drop-size distribution was examined using two specially designed airblast atomizers. Both were constructed to produce a flat liquid sheet across the centerline of a two-dimensional air duct with the liquid sheet exposed on both sides to high velocity air. In one case a thin film of uniform thickness was produced by injecting the liquid through a porous plate located just upstream of the atomizing edge. The film thickness, t, was then measured by a needle contact device. In the second design the fuel entered the air stream through a thin slot whose height could be adjusted accurately to vary and control the initial film thickness. Drop sizes were measured by the well-established light-scattering technique. From analysis of the processes involved, and from correlation of the experimental data, it was found that high values of liquid viscosity and liquid flow rate result in thicker films. It was also observed that thinner liquid films produce better atomization, according to the relationship, SMD ∝ t0.38.

Background: Obesity is commonly associated with insulin resistance (IR), and is a common cause of type 2 diabetes. Adiponectin is an adipose tissue protein that enhances insulin sensitivity and has anti-atherogenic properties. Objective: This study was done to determine the adiponectin level and its relations to key components of the metabolic syndrome in obese diabetic (OD), obese non-diabetic (OB) and control [non-obese, non-diabetic (NOND)] Qatari subjects. Research design and Methods: We examined 64 (OD), 61 (OB) and 72 (NOND) male and female subjects. After a 12 h overnight fasting, blood samples were withdrawn for determination of plasma glucose, insulin, adiponectin, HbA1C, uric acid, total cholesterol, triglycerides, HDL-C and LDL-C. Results: Plasma levels of adiponectin in OD (10.60 ± 3.64μg/mL) and OB (11.21 ± 3.41μg/mL) were significantly lower than NOND controls (14.73 ± 4.97μg/mL). Significant, inverse correlations were observed between adiponectin levels and BMI (r=-0.241, p<0.05), plasma glucose (r=-0.221, p<0.05), insulin (r=-0.280, p<0.05), C-peptide (r=-0.334, P<0.01), total cholesterol (r=-0.243, p<0.01,), triglycerides (r=-0.438, p<0.01), LDL-C (r=-0.214, p<0.05) and uric acid (r=-0.286, p<0.05). In addition, correlated positively with HDL-C(r=0.386, p<0.01). In multiple regression analysis, only TG was inversely associated with plasma level of adiponectin in all groups. Conclusion: This study provides the first evidence that adiponectin is reduced in Qatari obese subjects with and without diabetes. The measurement of circulating adiponectin among Qatari obese subjects is suggested to monitor cardiovascular disease (CVD) risks. Whether the plasma adiponectin level could be a suitable biomarker for following the clinical progress of CVD among Qatari obese and diabetic subjects warrants further investigation.

Bowel resection surgery is a commonly performed operation used to treat a variety of gastro-intestinal tract disorders, including cancer. The surgery entails excising the diseased portion of intestine, and then creating a surgical anastomosis, or reattachment of the remaining ends. One of the major complications following bowel resection surgery is breakdown or leakage from the anastomosis, which affects 20% of patients, with an associated 10-15% mortality rate. The surgical creation of anastomosis frequently involves dividing blood vessels and can introduce unrecognized twists and tension on the intestine. As a result, the blood supply to the site of anastomosis is often hampered, limiting the oxygen supply that is essential for adequate anastomotic healing. We are proposing a device that enables surgeons to obtain real-time feedback on local tissue oxygen saturation (SpO2) during operative procedures. Such data will not only help surgeons realize any bowel oxygenation compromising maneuvers, but also help perform an anastomosis at the site of maximal tissue oxygenation, thus minimizing the occurrence of postoperative anastomotic leakage and improve patient outcomes. This report details the specifications, fabrication, operation and performance of a handheld wireless pulse oximeter suitable for the intraoperative measurement of tissue SpO2 during bowel surgery. The device adapts principles and technology developed for non-invasive pulse oximetry, and introduces tissue interface, physician tools, and signal processing algorithms for intra-operative application. The handheld device includes local display of SpO2 level (<1s refresh) at the contacted tissue, and signals the operator on degraded signal quality/faults. An onboard micro-controller digitizes and processes signals transduced through a controlled LED array. Signal processing and display parameters were optimized for operating room conditions. A disposable functionally-transparent cover provides both device and tissue protection. Through serial or Bluetooth wireless transmission (250 Kbps), SpO2 and pulse signals can be processed on a PC or operating room VI. The incorporation of a pressure sensor to increase accuracy and robustness is explored. The device was validated intra-operatively on rodent and bovine surgical models.