The influence of extracellular tissue on neutrophil function and its possible linkage to inflammatory diseases

BACKGROUND

Migration, production of reactive oxygen species (ROS), release of myeloperoxidase (MPO), and NETosis are functional immunological reactions of elementary importance for polymorphonuclear neutrophils (PMN). Unregulated inflammatory response of PMN within tissues plays a key role in the pathophysiology of several diseases. However, little is known about the behavior of PMN after migration through blood vessel walls. Therefore, we investigated the influence of the extracellular matrix (ECM) on PMN function.

MATERIALS AND METHODS

We established an in vitro chemotaxis model of type I and III collagen, fibrin, and herbal agarose tissues using µ-slide chemotaxis devices and N-formylmethionine-leucyl-phenylalanine (fMLP). PMN within the matrices were assessed with a fluorescent time-lapse microscope for live-cell imaging.

RESULTS

PMN function was obviously influenced by the ECM. Type III collagen had an inhibitory effect on PMN migration regarding track length, direction, and targeting. Type III collagen also had an accelerating effect on neutrophil ROS production. Agarose had an inhibitory effect on MPO release and fibrin a retarding effect on NETosis.

CONCLUSION

Because of the high abundance of type III collagen in lung and skin matrices, the interaction of PMN with the respective matrix could be an important mechanism in the pathophysiology of acute respiratory distress syndrome and pyoderma gangrenosum.

Effects of Volatile Anesthetics on Proliferation and Viability of SW480 Colon Cancer Cells In Vitro

BACKGROUND/AIM

For patients undergoing cancer surgery, the risk for cancer progression is enhanced during the perioperative period. To what extent the type of anesthetic can affect the metastatic process and finally the outcome of patients with cancer is under debate. For this reason, the aim of this study was to investigate the effects of the volatile anesthetics sevoflurane and desflurane on colon cancer cells in vitro.

MATERIALS AND METHODS

SW480 colon carcinoma cells were exposed for 3 or 6 h to sevoflurane (1 or 2.5 vol%) or desflurane (6 or 12 vol%). Cell cycle distribution was analyzed by flow cytometry after a 24-72 h recovery and apoptosis was detected by annexin V staining after a 0-48 h recovery. Viability was tested by measuring ATP content after 0 and 24 h recovery.

RESULTS

Treatment with sevoflurane or desflurane caused no or only slight changes in cell-cycle distribution and apoptosis rate. Desflurane at 12vol% significantly reduced cell viability by 17±25% and 11±22% after 3 and 6 h incubation and 24 h recovery, respectively, while 2.5 vol% sevoflurane slightly increased viability.

CONCLUSION

At clinically relevant concentrations, sevoflurane and desflurane had only slight effects on SW480 colon cancer cells in vitro.

Acetaminophen and Metamizole Induce Apoptosis in HT 29 and SW 480 Colon Carcinoma Cell Lines In Vitro

BACKGROUND/AIM

The perioperative phase is supposed to be a period with high vulnerability for cancer dissemination. Acetaminophen and metamizole are common analgesics administered during this phase. We investigated the effect of acetaminophen, metamizole and 4-methylaminoantipyrine (MAA) on proliferation and apoptosis of colon carcinoma cell lines (SW 480 and HT 29).

MATERIALS AND METHODS

Proliferation was detected by cell proliferation ELISA BrdU, and apoptosis by Annexin V staining. Cytochrome c and caspase 3, 8 and 9 expression levels were detected by western blot.

RESULTS

Acetaminophen, metamizole or MAA caused slight changes in proliferation. Acetaminophen, metamizole or the combination increased apoptosis in both cell lines. All agents decreased caspase 3 and 8 expression in SW480. Acetaminophen decreased caspase 9 expression in both cell lines.

CONCLUSION

In clinically relevant doses, acetaminophen and/or metamizole induce apoptosis in both colon cancer cell lines. Both mitochondrial and death receptor pathways might be involved in acetaminophen-induced apoptosis.

The (in-)validity of volatile POCT parameters from patients beyond normothermia

BACKGROUND

A common characteristic of all blood gas analyzers on the market is that measurements are processed at 37°C, not at the real patients´ temperature. Subsequently temperature-sensitive parameters can be mathematically corrected (alpha-stat method) or used directly (pH-stat method). National rules in Germany (Rili-BAEK) demand defined accuracy and precision without any restriction to samples´ temperatures or corrections. As consequence in the investigation at hand we tried to find out whether blood gas analyzers can fulfill the regulations for pCO₂ and pO₂ when normothermia of the matrix is not given.

METHODS

Five matrices (blood from intensive care unit (ICU) patients, blood from healthy donors and 3 levels of bovine based quality control material) were tonometered at "high" and "low" partial pressures of O₂ and CO₂ within the RiLi-BAEK controlled range at 32, 37 and 40°C. One mL material was aspired into each blood gas (BG) syringe and analysis was accomplished immediately after. The procedure was repeated 10-fold for "high" and "low" gas concentrations and run on 4 different analyzers. At 18°C instead to the "high" one a "median" gas (n=10 as well) was employed. Every condition which constitutes of temperature (4), matrix (5), analyzer (4) and level of the partial pressure (2) led to a total of 1600 measurements.

RESULTS

At 32°C or 37°C matrix temperature 7.5% to 27.5% of the pCO₂(T) and between 14.5% and 28.1% of the pO₂(T) results were outside the borders required by the RiLi-BAEK. At 18°C or 40°C the number of results beyond the allowed borders grows up to 82.5% for pCO₂(T) and 73% for pO₂(T) depending on the partial pressure (PP) level.

CONCLUSIONS

High precision in automated quality control (at a constant matrix temperature) is given in modern BGAnalyzers but is counteracted in practice by non normothermic patient's temperature and unavoidable sample handling effects.

Effects of Lidocaine on HT-29 and SW480 Colon Cancer Cells In Vitro

BACKGROUND

Evidence is growing that the risk of cancer dissemination may be enhanced during the perioperative period. Whether particular anesthetic techniques influence oncological outcome is still under discussion. For pain management, lidocaine can be administered perioperatively by intravenous, intraperitoneal or epidural infusion. Here we investigated the effect of lidocaine on colon carcinoma cell lines (HT-29 and SW480) in vitro.

MATERIALS AND METHODS

ELISA BrdU (Roche) for cell proliferation and FITC Annexin V detection kit (BD Pharming) for apoptosis analysis were applied. Cell-cycle profiles were investigated by flow cytometry.

RESULTS

Cell-cycle arrest was induced in both cell lines by 1000 μM lidocaine, while no inhibition of cell proliferation was detected. Apoptosis decreased in SW480 but not in HT-29 cells.

CONCLUSION

Lidocaine induces cell-cycle arrest in both colon carcinoma cell lines in vitro. The effective drug concentration can be obtained by local infiltration.

Preanalytics: The (in-)stability of volatile POCT parameters and the homogeneity of blood in syringes at the market

BACKGROUND

In between calibrations, quality controls and so on reduce the availability of blood gas analyzers. Despite the intended urgency of the measurements, these inhibitory circumstances cause delays of measurements. The comparison of changes (primarily PO2 and PCO2, secondarily ctHb) in syringes from different suppliers and the embedding into guideline ranges are the objectives of this study.

METHODS

Five matrices were tonometered at two levels within the German guideline (RiLi-BAEK) controlled range. Matrices were aspired into each syringe and blood gas analysis accomplished after 0 to 30min. The procedure was repeated 5 to 8-fold for the gas concentrations and every condition which consisted of syringe type (7), matrices (5) and time delay (7).

RESULTS

Syringes produce almost identical effects on partial pressures during the 30min observation period. Initial fast changes arise when partial pressure (PP) differs widely from the atmospheric pressure and are followed by diffusion, gas production or consumption and ctHb depending effects.

CONCLUSIONS

Only normal arterial blood gases without "atmospheric pollution" are not affected by the syringe materials within 30min. The homogeneity of a de-aerated and capped ICU-patients' sample is hardly to be provided after more than 10min of resting without mechanical assistance.

Integrative normalization and comparative analysis for metabolic fingerprinting by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry

Comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC x GC-TOF-MS) was applied to the comparative metabolic fingerprinting of a wild-type versus a double mutant strain of Escherichia coli lacking the transhydrogenases UdhA and PntAB. Using peak lists generated with the Leco ChromaTOF software as input, we developed retention time correction and data alignment tools (INCA). The accuracy of peak alignment and detection of 1.1- to 4-fold changes in metabolite concentration was validated by a spike-in experiment with 20 standard compounds. A list of 48 significant features that differentiated the two E. coli strains was obtained with an estimated false discovery rate (FDR) of <0.05. A total of 27 metabolites, mainly from the citrate cycle, were identified. That the signal intensity of the m/z 73 trace of the trimethylsilyl (TMS) group reflected true differences in metabolite abundance was confirmed by quantification of pyruvate, fumarate, malate, succinate, alpha-ketoglutarate, citrate, cis-aconitate, myo-inositol, and glucose-6-phosphate using compound specific fragment ions and stable isotope labeled standards. Relative standard deviations for metabolite extraction and GC x GC-TOF-MS analysis of those analytes ranged from 13.2 to 26.3% for the universal m/z 73 trace and 7.4 to 24.5% for the analyte specific fragment ion trace.

Toddler's fracture: presumptive diagnosis and treatment

The diagnosis of a toddler's fracture is frequently difficult at the initial evaluation because of negative radiographs. We propose the presumptive diagnosis of toddler's fracture, despite negative radiographs, when the history and physical examination are consistent with the diagnosis. This retrospective study was designed to evaluate how frequently the diagnosis is correct and to determine if there were any differentiating characteristics with respect to history, gait, or physical examination. Thirty-nine children were presumptively diagnosed with toddler's fracture. A total of 16 (41%) toddler's fractures was confirmed on follow-up radiographs. Comparing the children who demonstrated a toddler's fracture with those who did not, no particular characteristic was found that could predict the outcome. To avoid delay in the treatment of toddler's fracture, we recommend a long-leg cast on those children with a history of an acute injury, inability to walk or limp, no constitutional signs, and negative radiographs.

Non-destructive evaluation of membrane lung gas exchange performance

This paper describes a method of evaluating the gas exchange effectiveness of hollow fiber oxygenators utilizing gas on both sides of the membrane. The goal of the study was to develop an evaluation technique which was accurate, reliable, and did not harm or contaminate a new, sterile oxygenator. Three pediatric oxygenators were tested and compared: the Medtronic Minimax Plus, the Terumo Capiox 320, and the Sorin Masterflo 34 (all with rated blood flows of 2-2.5 L/min). Gas entering the "blood" side was a mixture of CO2, O2, and N2 in a mixture matching typical venous blood partial pressures. The "blood" flows used were 0.5, 1, 1.5, or 2 L/min. Gas entering the gas port had an FiO2 of 0.4 flowing at 0.5, 1, 1.5, 2, 2.5, 3, or 3.5 L/min. Fractional contents of CO2 and O2 at all inlets and outlets were determined using a gas analyzer and converted to partial pressures. Efficacy indices and gas transfer rates were calculated and compared. Of the devices studied, the Masterflo 34 had the highest gas transport rates and effectiveness followed by the Minimax-Plus and the Capiox 320. Reversing the direction of the flow through the "blood" phase of the Minimax-Plus greatly changed its gas exchange effectiveness. The techniques described in this study should allow for a more uniform and consistent evaluation of gas exchange by membrane lungs which can be made inexpensively and relatively quickly. In addition, these methods should allow manufactures to evaluate gas exchange effectiveness and transfer rates of individual units during production as well as reduce the complexity involved when evaluating newly developed oxygenators.

The posterior approach to the elbow revisited

This retrospective study evaluates the clinical results of those patients with displaced pediatric elbow fractures who were surgically treated by using a modified posterior approach. Twenty patients were evaluated at an average follow-up time of 17.6 months. At the time of final follow-up, 19 of 20 patients had regained full flexion, and 18 of 20 patients had regained full extension. There were no angular deformities, loss of strength, late nerve palsies, or cases of avascular necrosis. Anatomic reduction is the key in the treatment of displaced pediatric elbow fractures. In our experience, the posterior approach to the elbow allows exact anatomic reduction, with no resultant angular deformities, and a range of motion that is comparable to other reported approaches.

Percutaneous screw removal in slipped upper femoral epiphysis

Several authors have reported complications from screw removal after treatment of slipped upper femoral epiphysis by single screw fixation, and have attributed these to poor screw design. We have developed a simple and reliable method of screw removal which uses a cannulated 8.0 mm end-threaded cancellous screw (Smith & Nephew Richards Medical, Memphis, Tennessee) and a specially designed cannulated trephine. The method has been successful, with minimal complications, and a limited surgical exposure.

Increased plasma oncotic pressure inhibits pulmonary fluid transport when pulmonary pressures are elevated

Hydrostatic and oncotic pressures are the primary determinants of fluid movement across the pulmonary vascular membrane. The precise role of oncotic pressure in regulating transvascular fluid exchange especially when hydrostatic pressure is high is not known. Awake, adult sheep were instrumented for pressure monitoring and the collection of pulmonary lymph. A left atrial (LA) balloon catheter was utilized to control LA pressure. Statistically significant increases in lymph protein flux were seen with infusion of saline and elevated pulmonary microvascular pressure (Pmv) over elevated Pmv alone (15.3 +/- 1.23 versus 11.2 +/- 1.09 mg/min) concomitant with a decrease in plasma colloid oncotic pressure (COP) (14.9 +/- 0.5 versus 16.9 +/- 0.5 mm/Hg). The protein flux seen with elevated Pmv and saline infusion was blunted when plasma was infused (13.8 +/- 1.58 mg/min) and the plasma COP augmented (18.1 +/- 0.05 mg Hg) but was not statistically different. We conclude that under conditions of stable membrane permeability and elevated Pmv, the plasma COP appears to be an important mechanism for protection against pulmonary edema.

Intertrochanteric fractures of the hip in the elderly: a retrospective analysis of 236 cases

A series of 236 patients over the age of 80 with intertrochanteric fractures were treated on a protocol established basis in an attempt to decrease postoperative morbidity and mortality. Rigid fixation with interfragmentary compression using the compression hip screw permitted us to begin early mobilization and immediate weight-bearing. Vigorous pulmonary tiolette, prophylactic antibiotics, and aspirin "anticoagulation" were used as adjuncts. Three month mortality was 7%. Overall, 76% of the patients who ambulated in any manner before their fracture walked again after surgery. Many, however, lost one grade level of walking postoperatively. Effective treatment for a patient with an intertrochanteric fracture, regardless of advanced age, is surgery and early mobilization.

A single stage osteotomy and epiphysiodesis for treatment of moderately displaced femoral capital epiphyses

Epiphysiodesis and subtrochanteric osteotomy have long been recognized as valuable procedures in the treatment of the patient with a moderately or markedly displaced femoral capital epiphysis. Typically these have been performed individually or sequentially. The operation herein described combines the two in one single-stage procedure. Using a stainless steel Lorenzo Screw, the epiphyseal plate is transfixed and further capital displacement prevented. The subtrochanteric compensatory osteotomy is performed using simple visual clinical guidelines and is held rigidly immobilized with a variable angle sideplate affixed to the Lorenzo Screw. The firm fixation enables one to dispense with plaster immobilization and begin the patient on an early exercise program. Restoration of a more normal range of motion, especially regarding rotation internally, abduction, and flexion is easily obtained. Radiographic correction of varus and posterior tilting are thereby secured.