Exposure of Monomolecular Lithographic Patterns to Ambient: An X-ray Photoemission Spectromicroscopy Study

Patterned self-assembled monolayers (SAMs) of alkanethiolates (AT) on Au and Ag substrates were imaged and characterized by scanning photoelectron microscopy (SPEM). The patterns were prepared in situ by direct writing with the zone-plate-focused X-ray beam provided by the SPEM station. Whereas both AT/Au and AT/Ag behaved alike upon the irradiation, which resulted in similar contrasts in the fabricated patterns and similar microspot spectra from the irradiated areas, the intensity relationship between the patterned and nonpatterned areas changed by different pathways for the Au and Ag substrates after the exposure of the patterns to ambient. The SPEM data imply that weakly bound molecular fragments are desorbed from the irradiated areas upon air exposure in the case of Ag, whereas adsorption of airborne molecules from ambient occurs for the Au substrate. The origin of the observed differences is presumably related to the specific branching patterns of irradiation-induced modification of AT/Au and AT/Ag.

Modification of Monomolecular Self-Assembled Films by Nitrogen−Oxygen Plasma

The modification of octadecanethiolate self-assembled monolayers on Au and Ag by nitrogen-oxygen downstream microwave plasma with variable oxygen content (up to 1%) has been studied by synchrotron-based high-resolution X-ray photoelectron spectroscopy. The primary processes were dehydrogenation, desorption of hydrocarbon and sulfur-containing species, and the oxidation of the alkyl matrix and headgroup-substrate interface. The exact character and the rates of the plasma-induced changes were found to be dependent on the substrate and plasma composition, with the processes in the aliphatic matrix and headgroup-substrate interface being mostly decoupled. In particular, the rates of all major plasma-induced processes were found to be directly proportional to the oxygen content in the plasma, which can be, thus, considered as a measure of the plasma reactivity. Along with the character of the observed changes, exhibiting a clear dominance of the oxidative processes, this suggests that the major effect of the oxygen-nitrogen downstream microwave plasma is provided by reactive oxygen-derived species in the downstream region, viz. long-living oxygen radicals and metastable species.

Proteomic profiling of erythrocyte proteins by proteolytic digestion chip and identification using two-dimensional electrospray ionization tandem mass spectrometry

Self-assembled monolayers (SAMs) on coinage metal provide versatile modeling systems for studies of interfacial electron transfer, biological interactions, molecular recognition, and other interfacial phenomena. The bonding of enzyme to SAMs of alkanethiols onto gold surfaces is exploited to produce an enzyme chip. In this work, the attachment of trypsin to a SAMs surface of 11-mercaptoundecanoic acid was achieved using water soluble N-ethyl-N'-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide as coupling agent. A two-dimensional liquid-phase separation scheme coupled with mass spectrometry is presented for proteomic analysis of erythrocyte proteins. The application of proteomics, particularly with reference to analysis of proteins, will be described. Surface analyses have revealed that the X-ray Photoelectron Spectroscopy (XPS) C1s and N1s core levels illustrate the immobilization of trypsin. These data are also in good agreement with Fourier Transformed Infrared Reflection-Attenuated Total Reflection (FTIR-ATR) spectra for the peaks at Amide I and Amide II. Using two-dimensional nano-high performance liquid chromatography electrospray ionization tandem mass spectrometry (2D nano-HPLC-ESI-MS/MS) system observations, analytical results have demonstrated the erythrocyte proteins digestion of the immobilized trypsin on the functionalized SAMs surface. For such surfaces, it also shows the enzyme digestion ability of the immobilized trypsin. The experiment results revealed the identification of 272 proteins from erythrocyte protein sample. The terminal groups of the SAMs structure can be further functionalized with biomolecules or antibodies to develop surface-base diagnostics, biosensors, or biomaterials.

Proteomic profiling of platelet proteins by trypsin immobilized self-assembled monolayers digestion chip and protein identification using electrospray ionization tandem mass spectrometry

Self-assembled monolayers (SAMs) on coinage metal provide versatile modeling systems for studies of interfacial electron transfer, biological interactions, molecular recognition, and other interfacial phenomena. Recently, the bonding of enzyme to SAMs of alkanethiols onto Au electrode surfaces was exploited to produce a bio-sensing system. In this work, the attachment of trypsin to a SAMs surface of 11-mercaptoundecanoic acid was achieved using water soluble 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysulfosuccinimide as coupling agent. Experimental results have revealed that the X-ray Photoelectron Spectroscopy (XPS) C1s core levels at 286.3 and 286.5 eV (C with N), 288.1 eV (amide bond), and 289.3 eV (carboxyl) illustrate the immobilization of trypsin. These data were also in good agreement with Fourier-Transformed Infrared Reflection-Attenuated Total Reflection (FTIR-ATR) spectra for the peaks valued at 1659.4 cm(-1) (amide I) and 1546.6 cm(-1) (amide II). Using electrospray ionization tandem mass spectrometry (ESI-MS/MS) observations, analytical results have demonstrated the platelet proteins digestion of the immobilized trypsin on the functionalized SAMs surface. For such surfaces, platelet proteins were digested on the trypsin-immobilized SAMs surface, which shows the enzyme digestion ability of the immobilized trypsin. The terminal groups of the SAMs structure can be further functionalized with biomolecules or antibodies to develop surface-base diagnostics, biosensors, or biomaterials.

Characterization of trypsin immobilized on the functionable alkylthiolate self-assembled monolayers: a preliminary application for trypsin digestion chip on protein identification using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

Self-assembled monolayers (SAMs) on coinage metal provide versatile modeling systems for studies of interfacial electron transfer, biological interactions, molecular recognition and other interfacial phenomena. Recently the bonding of enzyme to SAMs of alkanethiols onto Au electrode surfaces was exploited to produce a bio-sensing system. In this work, the attachment of trypsin to a SAMs surface of 11-mercaptoundecanoic acid was achieved using water soluble N-ethyl-N '-(3-dimethylaminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide as coupling agent. The thickness of SAMs was determined by optical ellipsometer; contact angles of the modified Au surfaces were measured in air using a goniometer. The Second Harmony Generation data displays the last few percents of the alkylthiol molecules adsorbed and produced the complete monolayer by inducing the transition from a high number of gauche defects to an all-trans conformation. Using X-ray Photoelectron Spectroscopy (XPS) and Fourier-Transformed Infrared Reflection-Absorption and Attenuated Total Reflection Spectroscopes (FTIR-RAS and ATR), we examined the chemical structures of samples with different treatments. By matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), we demonstrated the digestion of bovine serum albumin (BSA) on the trypsin-immobilized SAMs surface. Experimental results have revealed that the XPS C1s core levels at 286.3 and 286.5 eV (Amine bond), 288.1 eV (Amide bond) and 289.3 eV (Carboxylic acid) illustrate the immobilization of trypsin. These data were also in good agreement with FTIR-ATR spectra for the peaks valued at 1659.4 cm(-1) (Amide I) and 1546.6 cm(-1) (Amide II). Using MALDI-TOF MS observations, analytical results have demonstrated the BSA digestion of the immobilized trypsin on the functionalized SAMs surface. For such surfaces, BSA was digested on the trypsin-immobilized SAMs surface, which shows the enzyme digestion ability of the immobilized trypsin. The terminal groups of the SAMs structure can be further functionalized with biomolecules or antibodies to develop surface-base diagnostics, biosensors, or biomaterials.

Modification of aliphatic self-assembled monolayers by free-radical-dominant plasma: the role of the plasma composition

Modification of octadecanethiolate self-assembled monolayers on Au by nitrogen-oxygen or argon-oxygen downstream microwave plasma with a low oxygen content (estimated below several percent) has been studied by synchrotron-based high-resolution X-ray photoelectron spectroscopy and water contact angle measurements. For both types of plasma, the primary processes were found to be the loss of conformational and orientational order and the oxidation of the alkyl matrix and headgroup-substrate interface. At the same time, the film modification occurred much faster and with different intermediates for the nitrogen plasma than for the argon plasma. The reasons for these differences are considered in terms of the different reactivities and different efficiencies of the energy transfer between the plasma constituents in these two types of plasma.

Chemisorption and reaction characteristics of methyl radicals on Cu(110)

Methyl radicals are generated by pyrolysis of azomethane, and the condition for achieving neat adsorption on Cu(110) is described for studying their chemisorption and reaction characteristics. The radical-surface system is examined by X-ray photoemission spectroscopy, ultraviolet photoemission spectroscopy, temperature-programmed desorption, low-energy electron diffraction (LEED), and high-resolution electron energy loss spectroscopy under ultrahigh vacuum conditions. It is observed that a small fraction of impinging CH3 radicals decompose into methylene possibly on surface defect sites. This type of CH2 radical has no apparent effect on CH3(ads) surface chemistry initiated by dehydrogenation to form active CH2(ads) followed by chain reactions to yield high-mass alkyl products. All thermal desorption products, such as H2, CH4, C2H4, C2H6, and C3H6, are detected with a single desorption peak near 475 K. The product yields increase with surface coverage until saturation corresponding to 0.50 monolayer of CH3(ads). The mass distribution is, however, invariant with initial CH3(ads) coverage, and all desorbed species exhibit first-order reaction kinetics. LEED measurement reveals a c(2 x 2) adsorbate structure independent of the amount of gaseous exposure. This strongly suggests that the radicals aggregate into close-packed two-dimensional islands at any exposure. The islanding behavior can be correlated with the reaction kinetics and is deemed to be essential for the chain propagation reactions. Some relevant aspects of the CH3/Cu(111) system are also presented. The new results are compared with those of prior studies employing methyl halides as radical sources. Major differences are found in the product distribution and desorption kinetics, and these are attributed to the influence of surface halogen atoms present in those earlier investigations.

Anticoagulant activity of immobilized heparin on the polypropylene nonwoven fabric surface depending upon the pH of processing environment

Antenna coupling microwave plasma enables a highly oxidative treatment of the outmost surface of polypropylene (PP) nonwoven fabric within a short time period. Subsequently, grafting copolymerization with acrylic acid (AAc) makes the plasma-treated fabric durably hydrophilic and excellent in water absorbency. With high grafting density and strong water affinity, the pAAc-grafted support greatly becomes feasible as an intensive absorbent and as a support to promote heparin immobilization through amide bonds. For heparin immobilized in acidic condition, the carbonate groups of the molecule tend to dissolve and passive encapsulation of the molecule prevents its functional groups from bonding with the carboxylic acid of pAAc. This effect leads to inhibit the immobilization process and consequently reduces the quantity as well as the bioactivity of the immobilized heparin. In alkaline processing environment, the oxidized uronic acid residues in heparin-related glycans are presumably cleaved and the removal of some oxidized residuals before immobilization process is likely to reduce the chain length of heparin. In the latter case, anticoagulant Factors X and XII, but not thrombin, are unaffected. Anticoagulant activity test using activated partial thromboplastin time (aPTT) is more sensitive in assessing heparin-immobilized surfaces, since it corresponds to Factor X and initiates the inhibition of Factor XII and thrombin. Likewise, platelets adhesion on the surfaces decreases as the process shifted from acidic to alkaline condition, whereas the hydrophilic character of the grafted pAAc markedly contributes to extend physical insertion of platelets. The immobilized heparin has a great part of original bioactivity, depending on the pH of the processing environment and the immobilized quantity. Relative bioactivity based upon aPTT tests is partially held longer than 90 days for the sample prepared in the alkaline or neutral environment.

Assessment and characterization of degradation effect for the varied degrees of ultra-violet radiation onto the collagen-bonded polypropylene non-woven fabric surfaces

Exposure to ultra-violet (UV)-C radiation is a frequently used method to prevent bacteria from invasion of blood-contact biomedical products. Potential damage induced by UV radiation to collagen is of concern due to the decay of bioactivity, considerably correlated with structural alterations. Our current investigation studies the collagen-bonded non-woven polypropylene (PP) fabric surface. In this experiment, antenna-coupling microwave plasma is utilized to activate PP fabric and then the sample is grafted with acrylic acid (AAc). Type III collagen is immobilized by using water soluble 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide as coupling agent. The collagen-bonded samples with sample temperature ca. 4 degrees C are then exposed to UV-254nm radiation for different time intervals. By using fourier-transformed infrared with attenuated total reflection (FTIR-ATR) and XPS (X-ray photoelectron spectroscopy), we examine the chemical structures of samples with different treatments. Coomassie brilliant blue G250 method is utilized to quantify the immobilized collagen on the PP fabric surfaces. Blood-clotting effects are evaluated by activated partial thromboplastin time, thrombin time, and fibrinogen concentration tests. By means of cell counter and scanning electron microscopy we count red blood cells and platelets adhesion in the modified porous matrix. Our experimental results have demonstrated that with pAAc-grafting of ca. 173 microg cm(-2) and immobilized collagen of 80.5+/-4.7 microg cm(-2), for human plasma incubated samples of various intervals of UV-254 nm radiation, fibrinogen concentration decreases in human plasma, while platelets and red blood cells adhesions increase before UV radiation. However, the required time for thrombination shows significant change for UV radiation exposure of less than 20 h (alpha = 0.05). The decay of bioactivity for the UV-irradiated, collagen-bonded surfaces is thus evaluated. Surface analyses indicate that the decrease of R-COOH (derivated from grafted-pAAc or de-carboxylation of collagen), amides degradation (broken-NH), and phenylalanine scission (terminated by -OH, tyrosine formation) may gradually damage collagen by increasing the intervals of UV radiation. These effects considerably influence the bioactivity of the collagen-bonded fabric. The XPS measurements of C 1s core levels at 288.4 eV (O = C-NH) and at 289.1 eV (O = C-O) illustrate significant decreases of intensity after radiation time ca. 44 h. It is clear that UV-254 nm radiation exposure for ca. 20 h has the potential impact to moderate the bioactivities of collagen and therefore act as a vital factor to accelerate biodegradation.

New developments in the management of cytomegalovirus infection and disease after renal transplantation

The clinical management of cytomegalovirus infection and disease in renal transplant recipients has recently been significantly improved with the availability of data on prophylaxis with oral ganciclovir and valacyclovir. In addition, significant progress in early diagnosis and the quantitation of viral load has been achieved. The influence of novel immunosuppressants on the clinical course of cytomegalovirus infection has been clarified to some extent by recent clinical data. The identification of risk factors for cytomegalovirus disease beyond seroconstellation and immunosuppression is an ongoing process that might lead to a more targeted use of antiviral agents, given the risk of ganciclovir resistance. The understanding of the effects of cytomegalovirus on long-term graft outcome still needs to be deepened in order to design cytomegalovirus-specific interventions to improve graft survival.

Rapidly progressive glomerulonephritis and carcinoma of the hypopharynx

We report on a 50-year-old man with rapidly progressive glomerulonephritis and carcinoma of the hypopharynx. Because cancer treatment was followed by remission of proteinuria and complete restoration of renal function, a causal relationship between tumor and glomerular injury seems possible.

Long-term oral ganciclovir prophylaxis for prevention of cytomegalovirus infection and disease in cytomegalovirus high-risk renal transplant recipients

BACKGROUND

Although specific therapy is available with ganciclovir, cytomegalovirus (CMV) disease remains a major problem after renal transplantation especially in CMV seronegative recipients of organs of seropositive donors (D+R-).

METHODS

In an open-labeled prospective controlled trial we evaluated the effect of long-term oral ganciclovir prophylaxis (3 g/day for 3 months posttransplantation) in a cohort of 31 CMV-high risk (D+R-) renal transplant recipients (GC) compared with a cohort of 28 high-risk patients with targeted CMV prophylaxis (CO) receiving i.v. ganciclovir during antirejection therapy. Primary end-points were CMV infection, diagnosed by pp65 antigenemia assay or serologic method, and CMV disease. Additionally severity of CMV disease quantified by a scoring system was evaluated.

RESULTS

CMV prophylaxis significantly reduced the incidence of CMV infection (CO: 75%, GC: 45%; P<.05) and CMV disease (CO: 60%, GC: 29%; P<.05) without relevant side effects and without any clinical suspicion of ganciclovir resistance. Severity of CMV disease as quantified by a scoring system was reduced from 8.3+/-6.7 points in controls to 3.3+/-2.6 points in ganciclovir-treated patients (P<.05). Mortality did not differ significantly between the two groups (CO: n=3, GC: n=1; NS). However, there was one lethal CMV disease and a second death possibly attributable to CMV disease in the control group, whereas in ganciclovir-treated patients there was no CMV-associated fatal outcome.

CONCLUSION

Long-term oral ganciclovir prophylaxis is effective and safe in CMV high-risk renal transplant recipients.

The Soft X-ray Scanning Photoemission Microscopy Project at SRRC

The Synchrotron Radiation Research Center (SRRC) and the Institute of Atomic and Molecular Sciences (IAMS) have initiated a project to construct a scanning photoelectron spectromicroscopy end station at SRRC (SRRC-SPEM). High-brightness soft X-rays will be provided by the U5 undulator beamline. Zone-plate-based soft X-ray optics will be used to focus the beam to form the microprobe. A hemispherical sector analyser with multichannel detection capability will collect the photoelectrons. A total of up to 32 images can be acquired concurrently. The apparatus is also equipped with a sample distribution system for in situ sample preparation and characterization in conjunction with other surface spectroscopic techniques.

Impact of high-dose oral acyclovir prophylaxis on cytomegalovirus (CMV) disease in CMV high-risk renal transplant recipients

Recent studies showed contradictory results concerning the efficacy of oral acyclovir in the prevention or amelioration of cytomegalovirus (CMV) disease after renal transplantation (TX). This study evaluated the incidence and severity of CMV disease within the first year after TX in high-risk renal transplant recipients (CMV-seropositive donor, seronegative recipient) treated prophylactically with oral acyclovir (800 to 3200 mg/day) over a period of 12 wk (ACY, N = 22), compared with high-risk patients randomly assigned as controls (CO, N = 10). Follow-up for CMV infection included serological determination of CMV-specific immunoglobulin G and immunoglobulin M antibodies, antigen detection in peripheral blood leukocytes (PP 65), shell vial culture (blood), and virus isolation/early antigen detection (urine). Severity of CMV disease was quantified by a scoring system for CMV-related symptoms. Nine patients (40.1%) in the acyclovir group and four patients (40%) in the control group developed CMV disease. Neither severity (ACY, 11.4 versus CO; 12.5 points score), nor duration of disease (ACY, 21 days; CO, 22 days), nor transplant function at the end of the observation period differed significantly. The onst of CMV disease was not delayed significantly in acyclovir-treated patients compared with controls (ACY, 47 +/- 34 days versus CO, 27 +/- 14 days after TX, not significant). Our results show no beneficial effect of oral acyclovir prophylaxis in CMV high-risk renal transplant recipients.

Effect of danazol-induced chronic hyperglucagonaemia on glucose tolerance and turnover

It has been shown that danazol (14-ethinyltestosterone) induces hyperglucagonaemia. To investigate the effect of chronic glucagon excess on carbohydrate metabolism, we studied six patients before and after treatment with danazol for immunothrombopenia. Glucose tolerance and insulin, C-peptide and glucagon secretion during an oral glucose tolerance test (oGTT) as well as peripheral and hepatic insulin sensitivity were determined by means of euglycaemic clamp technique (40 mU m-2 min-1) before and after 3 months of danazol therapy. Overall glucose turnover (Rd) was assessed radioisotopically. (1) Plasma glucagon levels rose significantly from 88 +/- 16 pg mL-1 before to 683 +/- 148 pg mL-1 after therapy (P < 0.01). (2) Glucose levels during an oGTT were not significantly different before and after therapy. Glucose-stimulated insulin secretion at 60 and 120 min and the area under the curve (AUC) for insulin during the oGTT, were significantly increased after danazol treatment compared with pre-treatment values (P < 0.05), whereas glucagon secretion showed a similar decrease at both time points of investigation (NS). (3) Rd during steady state showed a significant decrease during the entire period of euglycaemic clamp following therapy (after 240 min, 3.8 +/- 0.6 vs. 5.3 +/- 0.7 mg kg-1 min-1, P < 0.05). The decline in glucagon during the clamp was similar during steady state before and after therapy. (4) Basal hepatic glucose output did not differ significantly before and after therapy (1.74 +/- 0.41 vs. 1.45 +/- 0.22 mg kg-1, NS), whereas hepatic glucose output during the clamp was significantly less suppressed after danazol therapy. The authors conclude that chronic glucagon excess leads to a decrease in peripheral and hepatic insulin action which is accompanied by an increase in insulin secretion.

Effect of repeated Aprosulate and Enoxaparin administration on tissue factor pathway inhibitor antigen levels

Tissue factor pathway inhibitor (TFPI) is a naturally occurring, Kunitz-type serine protease inhibitor whose anticoagulant activity is due to an inhibition of the extrinsic coagulation pathway. Heparin injection has previously been shown to increase the plasma levels of TFPI. In this study, plasma samples were obtained from a multiple dose phase I tolerance study with a synthetic analogue of heparin, namely Aprosulate (PALLAS). Volunteers were randomized into four treatment groups: (A) 35 mg Aprosulate b.i.d. s.c.; (B) 70 mg Aprosulate b.i.d. s.c.; (C) 70 mg Aprosulate o.d. + placebo o.d. s.c.; (D) 40 mg of a low molecular weight heparin, Enoxaparin o.d. + placebo o.d. s.c. All treatments were for 7 days, with blood samples taken periodically over this time period. TFPI antigen levels were determined using Imubind TFPI ELISA kits (American Diagnostica, Greenwich, CT). TFPI antigen levels were observed to rapidly increase to levels two- to three-fold over baseline in all groups. Aprosulate caused a slightly larger increase in TFPI antigen levels than Enoxaparin, though this may be related to the doses chosen for this study. These data indicate that plasma concentrations of TFPI are increased following Aprosulate administration. TFPI may be important in mediating the antithrombotic activity of Aprosulate.

Recombinant human erythropoietin in renal transplant recipients with renal anemia

Thirty-seven kidney graft recipients with chronically declining transplant function accompanied by renal anemia were treated with recombinant human erythropoietin for 3 months. In all these patients anemia improved and mean hemoglobin levels increased from 7.67 +/- 1.26 g/dl to 9.83 +/- 1.94 g/dl (p < 0.01). Mean creatinine increased from 4.23 +/- 1.82 to 4.62 +/- 2.42 (p < 0.05) but the progression of transplant failure was not influenced when compared with pretreatment values obtained at least 6 months before study entry. Mean blood pressure levels were not altered but 12 patients required additional antihypertensive medication.

Emergency intubation with the Combitube in a grossly obese patient with bull neck

A grossly obese patient with bull neck required immediate intubation. Endotracheal intubation failed because visualization of the vocal cords was not possible. As an alternative, the Combitube was inserted without difficulty and the patients lungs were ventilated via the Combitube until tracheotomy was performed on the following day. The patient survived and was discharged alive from the hospital 5 weeks later. The Combitube has gained worldwide interest and is now included in the Guidelines of the American Heart Association and the American Society of Anesthesiologists.

Emergency intubation with the Combitube: comparison with the endotracheal airway

STUDY OBJECTIVE

To evaluate the safety and effectiveness of the Combitude as used by ICU nurses under medical supervision compared with endotracheal airway established by ICU physicians during CPR.

DESIGN

Prospective study of ICU patients over a seven-month period.

SETTING

Medical ICU.

PARTICIPANTS

Thirty-seven patients suffering from cardiac arrest.

INTERVENTIONS

Emergency intubation with either the Combitube by nurses or the endotracheal airway by physicians and subsequent mechanical ventilation.

MEASUREMENTS AND MAIN RESULTS

Evaluation of blood gases after 20 minutes of mechanical ventilation. Intubation time was shorter for the Combitube (P < .001). Blood gases for each device showed comparable results; PaO2 was slightly higher during ventilation with the Combitube (P < .001).

CONCLUSION

The Combitube as used by ICU nurses was as effective as establishment of the endotracheal airway by intensivists during CPR. The Combitube may be used whenever endotracheal intubation cannot be performed immediately.

Cytokine release and dynamics of leukocyte populations after CD3/TCR monoclonal antibody treatment

Cytokine release and clinical side effects resulting from the use of OKT3 and BMA 031 monoclonal antibodies in the treatment of kidney graft recipients were evaluated and compared. The rise observed in serum levels of interferon gamma. TNF alpha, and IL-8 was similar after administration of either monoclonal antibody. Furthermore, both OKT3 and BMA 031 resulted in rapid disappearance not only of virtually all T cells, but also of substantial percentages of all major leukocyte populations from the circulation; this effect is probably due to cytokine release activating endothelial cells and thereby causing extravasation even of leukocytes not specifically recognized by the administered antibodies. Evidence has thus been obtained that BMA 031 is as potent as OKT3 in inducing unequivocal signs of T cell activation in vivo. However, while OKT3 therapy was accompanied by adverse side effects in our study as in previous ones, we saw no such reactions in any of the patients receiving BMA 031. This contrast might be due to different mechanisms of leukocyte activation possibly inducing other mediators in the case of OKT3, which then, in combination with the cytokines, could generate treatment-associated morbidity.

Massive upper airway bleeding after thrombolytic therapy: successful airway management with the Combitube

We present the case of a patient who required immediate intubation because of increasing upper airway bleeding. Endotracheal intubation failed because the glottis could not be visualized. An airway control device designed for cases of difficult emergency intubations was used successfully. This device can be inserted without the use of a laryngoscope.

Treatment of hyperlipidemic kidney graft recipients with lovastatin: effect on LDL-cholesterol and lipoprotein (a)

An increased incidence of hyperlipidemia places kidney graft recipients at increased risk for cardiovascular disease and may contribute to a decline in graft function. A study was undertaken to evaluate the safety and efficacy of lovastatin in these patients. Twelve kidney graft recipients with stable graft function and a cholesterol (chol) level over 250 mg/dl (6.46 mmol/l) were included. The lipid-lowering treatment consisted of 20 mg lovastatin daily, and all patients received immunosuppression with ciclosporin (CS) and prednisolone. Total chol decreased by 27% (300 +/- 56 to 219 +/- 28 mg/dl; 7.76 +/- 1.45 to 5.66 +/- 0.72 mmol/l; p < 0.01), LDL-chol by 35% (220 +/- 38 to 143 +/- 17 mg/dl; 5.69 +/- 0.98 to 3.70 +/- 0.44 mmol/l; p < 0.01) and triglycerides by 33% (207 +/- 127 to 138 +/- 56 mg/dl; 2.36 +/- 1.44 to 1.57 +/- 0.64 mmol/l; p < 0.05). HDL-chol increased by 10% (57 +/- 11 to 63 +/- 13 mg/dl; 1.47 +/- 0.28 to 1.63 +/- 0.34 mmol/l; NS). The ratio of total chol/HDL-chol, a generally accepted risk predictor of atherosclerosis, fell from 5.4 +/- 1.3 to 3.3 +/- 1.2, p < 0.01. Lipoprotein (a) [lp(a)], an independent risk predictor for atherosclerosis, was also evaluated at baseline and after 6 months of lovastatin treatment and showed a decrease of 39% (32.9 +/- 27.6 to 19.9 +/- 22.9 mg/dl; 0.85 +/- 0.71 to 0.51 +/- 0.59 mmol/l; p < 0.05). No adverse side effects were seen at this dosage, and hepatic and renal parameters remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Contribution of postprandial insulin and glucose to glucose disposal in normal and insulin-resistant obese subjects

We recently found that postprandial hyperinsulinemia does not compensate for the insulin resistance of obese subjects and proposed that postprandial hyperglycemia might be more important in promoting glucose disposal via the mass action effect of glucose. To test this idea we perform oral glucose tolerance tests (OGTT) in six lean and eight obese subjects, measuring glucose and insulin levels. Afterward two insulin infusion studies were performed. During infusion study I, insulin was infused in a dynamic square wave fashion to mimic the individual post-OGTT insulin levels at content euglycemic glucose levels. During study II, glucose and insulin infusions were varied to mimic post-OGTT levels in each subject. Overall glucose turnover was measured isotopically by infusion of [3-3H] glucose. During the OGTT the obese subjects exhibited significantly higher insulin (P less than 0.005) and glucose levels (P less than 0.002). Insulin-stimulated glucose disposal rates and total incremental glucose disposal (IGD) over 4 h during study I at euglycemia were significantly lower in obese compared to lean subjects (area under the curve, 824 +/- 166 vs. 1222 +/- 161 mmol/L.m2; P less than 0.01) despite higher post-OGTT insulin levels in obese subjects. When insulin plus glucose levels were matched to the individual OGTT levels, IGD was not significantly different between obese and control subjects (1712 +/- 253 vs. 1617 +/- 444 mmol/L.m2; P = NS). A significant inverse correlation (r = -0.73; P less than 0.05) existed between the degree of glucose intolerance (OGTT) and the decrease in IGD during the phasic hyperinsulinemic euglycemic study (infusion study I). These data suggest that with increasing insulin resistance, hyperinsulinemia is less effective in compensating for this decrease in insulin action, and hyperglycemia becomes more important in augmenting overall glucose disposal values.

Metabolic effects of isradipine versus hydrochlorothiazide in diabetes mellitus

Most antihypertensive drugs have negative effects on metabolic control in diabetic patients. Calcium antagonists have been widely used in antihypertensive treatment of diabetics, although a possible influence on glucose tolerance, insulin secretion, and insulin action is unknown. Therefore, the effect of the calcium antagonist isradipine on glucose tolerance and insulin secretion (75 g oral glucose tolerance test) and on peripheral and hepatic insulin action (euglycemic clamp) was evaluated in 11 type II diabetic patients. All patients were treated with placebo or isradipine for 8 weeks (double-blind, crossover design). A second group of six diabetic patients received a thiazide diuretic, hydrochlorothiazide, according to the same protocol. Systolic blood pressure was significantly lowered after isradipine and hydrochlorothiazide compared with placebo (127 +/- 3 versus 139 +/- 6 mm Hg and 129 +/- 4 versus 142 +/- 4, respectively; p less than 0.05). Fasting blood glucose (190 +/- 21 versus 152 +/- 15 mg/dl; p less than 0.01), glucose levels, basal and glucose-stimulated insulin levels were significantly higher after hydrochlorothiazide compared with placebo but remained unchanged after calcium antagonist treatment. Basal hepatic glucose production and peripheral insulin resistance were significantly elevated after hydrochlorothiazide compared with placebo or calcium antagonist therapy. These data indicate that the calcium antagonist isradipine has no effect on glucose tolerance, insulin secretion, and insulin action in type II diabetic patients and might therefore be a useful drug for antihypertensive treatment in diabetes mellitus. However, diuretic treatment can lead to impairment of metabolic control and reduction of insulin action in type II diabetes mellitus.

Decreased peripheral insulin sensitivity in acromegalic patients

In 13 nondiabetic acromegalic patients glucose homeostasis was studied by use of the hyperglycaemic clamp technique and compared to a group of sex and age matched and a group of sex, age and weight matched controls. When compared to a control group of normal weight glucose stimulated insulin release (I) was significantly increased and tissue sensitivity to insulin (M/I) significantly decreased. However, no significant differences were observed when the parameters were compared with a weight matched group. Glucose stimulated insulin release correlated positively with growth hormone (GH) and somatomedin-C levels, whereas no such a correlation could be obtained for M/I. Thus, chronic growth hormone excess seems to induce hyperinsulinaemia which in turn leads to obesity and metabolic changes comparable to those of obesity.