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Impact of PerioperAtive LidocAine Infusions on Enhanced Recovery After Noncardiac Surgery (IMPALA-ERAS) in an inpatient setting: rationale, design and protocol for a sequential, repeated crossover trial.

INTRODUCTION: Multimodal analgesic strategies designed to minimise perioperative opioid exposure are fundamental components of enhanced recovery after surgery (ERAS) pathways. Despite widespread implementation of ERAS protocols, the optimal analgesic regimen remains undefined, as the individual contributions of specific agents to overall analgesic efficacy and opioid-sparing effects are not fully elucidated. Intravenous lidocaine, a widely utilised local anaesthetic, possesses both analgesic and anti-inflammatory properties and has been associated with improved gastrointestinal recovery. This study seeks to pragmatically evaluate the impact of incorporating perioperative intravenous lidocaine infusion into established ERAS pathways on postoperative functional recovery. METHODS AND ANALYSIS: The Impact of PerioperAtive LidocAine Infusions (IMPALA) on ERAS trial is a single-centre, pragmatic, cluster-randomised, double-blinded, placebo-controlled study. A total of 2290 patients undergoing elective colorectal surgery, emergency general surgery, urology, ventral hernia repair, surgical oncology or spine surgery will be randomly assigned to receive either intraoperative and postoperative intravenous lidocaine infusions (administered for up to 48 hours) or placebo as part of a standardised multimodal analgesic regimen integrated into established ERAS pathways. The primary outcome is case mix index-adjusted resource length of stay, defined as the time interval from surgical initiation to hospital discharge adjusted for case mix index. The primary outcome is total inpatient opioid consumption within the first 72 hours, reported in oral morphine milligram equivalents. Secondary outcomes include various in-hospital clinical endpoints derived from the electronic health record. ETHICS AND DISSEMINATION: This protocol and accompanying statistical analysis plan outline the study design, primary and secondary endpoints and analytic methodology. The IMPALA-ERAS trial has received ethical approval from the Vanderbilt University Institutional Review Board (IRB: 250617). The findings will be disseminated via peer-reviewed publications and presentations at national conferences. Results from this trial are expected to inform evidence-based practices regarding perioperative lidocaine infusion and its potential contributions to enhanced postoperative recovery in surgical patients. TRIAL REGISTRATION NUMBER: NCT07224711.

Humans↗

Quantifying mechanical heterogeneity in canine acute lung injury: impact of mean airway pressure.

BACKGROUND: The heterogeneous pattern of acute lung injury (ALI) predisposes patients to ventilator-associated lung injury. Currently, there is no simple technique that can reliably quantify lung heterogeneity during the dynamic conditions of mechanical ventilation. Such a technique may be of use in optimizing mechanical ventilatory parameters such as rate, tidal volume, or positive end-expiratory pressure. METHODS: To determine the impact of heterogeneity on respiratory mechanics, the authors measured respiratory impedance (Zrs), expressed as respiratory resistance (Rrs) and elastance (Ers), in 11 anesthetized dogs from 0.078 to 8.9 Hz using broadband pressure and flow excitations under baseline conditions and after ALI produced by infusion of 0.08 ml/kg oleic acid into the right atrium. Data were obtained at mean airway pressures (Pao) of 5, 10, 15, and 20 cm H2O. The Zrs spectra were fit by various models of the respiratory system incorporating different distributions of parallel viscoelastic tissue properties. RESULTS: Under baseline conditions, both Rrs and Ers exhibited dependence on oscillation frequency, reflecting viscoelastic behavior. The Ers demonstrated significant dependence on Pao. After ALI, both the level and frequency dependence of Rrs and Ers increased, as well as the apparent heterogeneity of tissue properties. Both Rrs and Ers as well as heterogeneity decreased with increasing Pao, approaching baseline levels at the highest levels of Pao. CONCLUSIONS: These data demonstrate that Zrs can provide specific information regarding the mechanical heterogeneity of injured lungs at different levels of Pao. Moderate increases in Pao seem to be beneficial in ALI by reducing heterogeneity and recruiting lung units. These noninvasive measurements of lung heterogeneity may ultimately allow for the development of better ventilation protocols that optimize regional lung mechanics in patients with ALI.

Airway Resistance↗

Optimal timing for initial and redistribution technetium 99m-N-NOET image acquisition.

BACKGROUND: Bis (N-ethoxy, N-ethyl dithiocarbamato) nitrido technetium-99m (V) (Tc-99m-N-NOET) is a new Tc-99m-labeled myocardial perfusion imaging agent that redistributes. We sought to determine the optimal timing for acquiring initial and delayed images to maximize sensitivity for the detection of coronary stenoses. METHODS: Twelve anesthetized dogs with critical stenoses of the left anterior descending coronary artery were infused with adenosine (250 microg/kg/min) or MRE-0470, an adenosine A2a agonist (0.6 microg/kg/min x 10 minutes), and Tc-99m-N-NOET (8 mCi; 296 MBq) was injected intravenously at peak flow. Myocardial and lung Tc-99m-N-NOET activities were determined by serial quantitative imaging and arterial blood sampling was performed over 2 hours. RESULTS: Left anterior descending/left circumflex artery defect count ratios showed rapid redistribution during the first 10 minutes after Tc-99m-N-NOET injection (0.66 +/- 0.02 at 2 minutes to 0.73 +/- 0.01 at 10 minutes; P < .01). Redistribution was nearly complete by 120 minutes (defect ratio = 0.87 +/- 0.03; P < or = .01 vs 2 minutes). Lung activity fell significantly during the first 10 minutes from a heart/lung activity ratio of 1.07 +/- 0.05 (2 minutes) to 1.44 +/- 0.09 (10 minutes; P < or = .01). CONCLUSION: Initial stress Tc-99m-N-NOET images should be acquired within 10 minutes after injection, whereas delayed images can be obtained as early as 2 hours later. Lung activity clears rapidly, permitting acquisition of good-quality poststress cardiac images. These Tc-99m-N-NOET uptake and redistribution kinetics after vasodilator stress provide important information for designing clinical imaging protocols for optimal identification of inducible ischemia.

Animals↗

Optimal therapy for stress gastritis.

OBJECTIVE: The authors compared the results of sucralfate versus H2 blocker +/- antacid as prophylaxis for stress ulceration in an intensive care unit patient population. SUMMARY BACKGROUND DATA: Stress ulceration carries high morbidity and mortality for the patient who is critically ill. Gastric acid neutralization is an effective prophylaxis. The impact of increased gastric colonization with bacterial pathogens on nosocomial pneumonia after acid neutralization is unclear. The efficacy of sucralfate prophylaxis for stress ulceration and its the effect on the nosocomial pneumonia rate is controversial. The financial implications of sucralfate prophylaxis versus H2 blocker-based acid neutralization therapy has not been studied. METHODS: Ninety-eight injured patients who were critically ill and who required intubation and intensive care unit (ICU) support for at least 72 hours without gastric feeding were randomized and received either maximal H2 blocker infusion therapy (continuous infusion of ranitidine at 0.25 mg/kg/hr after a loading dose of 0.5 mg/kg) plus antacids (for persistent pH < 4) or sucralfate (1 g every 6 hours via nasogastric tube) for stress ulcer prophylaxis. Efficacy in preventing stress ulcer complications was determined. The impact of each therapeutic approach on development of nosocomial pneumonia was evaluated. The charges/cost for each approach was analyzed. RESULTS: Heme-positive gastric aspirates occurred in 99% of the patients, whereas 12 (7 in the H2 blocker group and 5 in the sucralfate group) were grossly positive for blood. However, only one from each group required transfusion, and one in the H2 blocker group required operation. Gastric colonization preceded tracheobronchial colonization in five patients in the H2 blocker group and one patient in the sucralfate group; simultaneous gastric/oropharyngeal colonization preceded positive tracheobronchial growth in six patients who received H2 blocker and one patient who received sucralfate. The overall pneumonia rate was 27.5% in the H2 blocker group and 20.8% in the sucralfate group (p = 0.48). Days on ventilator were 13.5 versus 9.1, (p = 0.06), ICU lengths of stay were 14.7 versus 10.2 (p = 0.06), and hospital lengths of stay were 27.8 versus 20.0 (p = 0.029) for the H2 blocker group and sucralfate group, respectively. Based on current charges and protocols for optimal H2 blocker and sucralfate prophylaxis, use of sucralfate rather than H2 blockers would decrease the annual cost by more than $30,000 per bed. CONCLUSIONS: Sucralfate is as efficacious as maximal H2 blocker therapy for stress ulceration prophylaxis, and may have a beneficial effect on the incidence of nosocomial pneumonia. Sucralfate has a major reduction on nursing requirements for stress ulcer prophylaxis and would save approximately $30,000 per ICU bed per year in patient charges.

Adult↗

[Multislice spiral CT angiography in the evaluation of the anatomy of splanchnic vessels: preliminary experience].

PURPOSE: The aim of this study was to optimize the protocol for multislice spiral CT angiography and to assess the ability of the technique to detect the anatomy of splanchnic vessels, using volume rendering as reconstruction algorithm. MATERIAL AND METHODS: The anatomy of splanchnic vessels was studied in 19 patients (11 men, 8 women, age range 38-83 years) undergoing CT of the abdomen and pelvis. All examinations were performed with a multislice spiral CT scanner (Somatom Plus 4 Volume Zoom; Siemens, Erlangen, Germany) using the following parameters: collimation, 1 mm; slice width, 1 mm; table feed, 8 mm/sec; reconstruction interval, 1 mm; mAs, 120; kVp, 120. Before the study, the patients received 800 ml of water as oral contrast agent to opacify the stomach and small bowel. A nonionic contrast medium (130-140 ml; Xenetix 350, Guerbet, Aulnay-Sous-Bois, France) was infused intravenously at a rate of 3-5 ml/sec. Two scans of the abdomen and pelvis were obtained at 20-25 sec (arterial phase) and 60-65 sec (venous phase) after starting contrast medium injection. Image elaboration was performed using Vitrea 2.2 (Vital Images; Minneapolis, Minn., USA), a software with volume-rendering capabilities. RESULTS: All major arterial (celiac trunk, superior mesenteric artery, and inferior mesenteric artery) and venous (portal vein, superior mesenteric vein, inferior mesenteric vein, and splenic vein) vessels could be evaluated with excellent detail in all patients. Side branches, including small collaterals, could also be easily visualized. Volume rendered images always provided better understanding of the 3D anatomic relationships among splanchnic vessels and surrounding organs. DISCUSSION AND CONCLUSIONS: Multislice spiral CT angiography allows for optimal depiction of the anatomy of splanchnic vessels. It can be anticipated that the clinical applications of this imaging modality in the study of splanchnic vessels will be greatly expanded. However, further studies are necessary to rigorously compare the results of multislice spiral CT angiography with conventional angiography in terms of diagnostic accuracy.

Adult↗

Serum-free ex vivo expansion of CD34(+) hematopoietic progenitor cells.

In an effort to obtain defined culture conditions for ex vivo expansion of hematopoietic stem and progenitor cells which avoid the supplementation of serum, we cultured human CD34(+) hematopoietic progenitor cells in a chemically defined, serum-free medium in the presence of hematopoietic growth factors (HGFs), stem cell factor (SCF), interleukin (IL)-1beta, IL-3, IL-6, and erythropoietin (EPO). A medium, SFM-1, was prepared according to a protocol previously optimized for semisolid progenitor cell assays containing Iscove's Modified Dulbecco's Medium (IMDM) plus cholesterol, bovine serum albumin, transferrin, nucleotides and nucleosides, insulin, and beta-mercaptoethanol. In static cultures seeded with CD34(+)-enriched progenitor cells isolated from human peripheral blood, a mean 76.6-fold expansion of total nucleated cells and a mean 4.6-fold expansion of colony-forming cells (CFC) was recorded after 14 days. Morphological analysis of the expanded cells revealed formation of myeloid, erythroid, and megakaryocytic cells. Flow cytometric analysis indicated that CD34(+) antigen expressing cells were maintained to a limited degree only, and cell populations expressing surface markers for myeloid (CD33, CD14, and CD15) and megakaryocytic (CD41a) lineages predominated. Within SFM-1, bovine serum albumin (BSA), cholesterin, and transferrin represented the most critical components needed for efficient total cell and CFC expansion. Addition of autologous patient plasma (APP) or fetal calf serum (FCS) to SFM-1 resulted in inferior cell amplification and CFC formation compared to controls in SFM-1, indicating that the components used in SFM-1 could replace exogenous serum. Four commercially available serum-free media resulted in either comparable or lower total cell and CFC yields as SFM-1. The transplantation potential of CD34(+) cells after culture in SFM-1 was assayed using limiting dilution analysis on preformed irradiated bone marrow stroma and revealed maintenance of long-term bone marrow culture initiating cell (LTCIC) levels during the culture period. These data indicate that HGF-supported multilineage ex vivo expansion of human CD34(+) hematopoietic progenitor cells is feasible using an IMDM-based culture medium which contains a restricted number of additives, resulting in analogous or improved yields of both primitive and differentiated cells compared to previously established protocols. We suggest that this culture protocol is of advantage when working with pharmaceutical-grade preparations under serum-free conditions.

Animals↗

Pre-operative localisation of hyperfunctional parathyroid tissue with 11C-methionine PET.

PURPOSE: Previous studies have shown high sensitivity of positron emission tomography (PET) with 11C-methionine in the pre-operative localisation of parathyroid adenoma and hyperplasia. Nonetheless, in secondary and tertiary hyperparathyroidism (HPT) and in patients with recurrent disease, pre-operative localisation of adenomatous (PTA) or hyperplastic tissue is still a problem with all available methods. The aim of this study was to define the optimal imaging protocol and to compare the diagnostic value of 11C-methionine PET and 99mTc-methoxyisobutylisonitrile (MIBI) single-photon emission computed tomography (SPECT): in particular, we wished to define the benefit of 11C-methionine in those patients with inconclusive or negative conventional imaging. METHODS: Thirty highly pre-selected patients with HPT were enrolled. Sixteen patients had primary HPT, 12 patients had secondary HPT, and two patients had recurrences of parathyroid carcinomas. All patients had ultrasound of the neck, dual-phase scintigraphy with 99mTc-MIBI and PET with 11C-methionine. SUV(parathyroid)/SUV(cervical soft tissue) (target-to-background) and SUV(parathyroid tissue)/SUV(thyroid tissue) (target-to-non-target) ratios were calculated. After surgery, histology of specimens was obtained in all patients but one. RESULTS: In 12 patients with secondary or tertiary HPT, 36 hyperplastic parathyroid glands were histologically verified. Twenty-five of 36 lesions (69%) were detected with 11C-methionine PET and 17 (47%) with 99mTc-MIBI scintigraphy. PET studies were positive in 17/18 (94%) cases in which HPT was related to adenomas or carcinomas. 99mTc-MIBI scintigraphy/SPECT yielded pathological lesions in 9/18 cases (50%). All eight atypical localisations of parathyroid glands were detected with PET but only six of the eight were detected with 99mTc-MIBI scintigraphy/SPECT. In 10/11 patients with recurrent HPT and non-diagnostic scintigraphy/SPECT, hyperfunctional parathyroid tissue was identified with 11C-methionine PET. The highest SUV(parathyroid)/SUV(cervical soft tissue) ratio was found 10 min, and the highest SUV(parathyroid tissue)/SUV(thyroid tissue) ratio 40 min post injection. In three patients clear delineation of hyperfunctional tissue was only achieved after 40 min post injection. CONCLUSION: 11C-methionine PET is a clinically useful method in highly pre-selected patients with recurrent primary HPT as well as in secondary and tertiary HPT if ultrasound and 99mTc-MIBI SPECT are inconclusive or negative. PET imaging of atypical PTA localisations is more accurate than conventional scintigraphy. In order to achieve optimal contrast of parathyroid glands versus thyroid tissue and adjacent soft tissue, imaging at both 10 min and 40 min is recommended.

Adult↗

Improvements in automated PNA synthesis using Boc/Z monomers.

An optimized automated PNA synthesis protocol is reported. Under optimal conditions the product yield of a test 17-mer PNA is approximately 90%. The average coupling yield is 99.4%. The synthesis strategy is Boc/Z and the deprotected amine is neutralized in situ. The monomers are added in molar excess to HATU and pre-activated for 60 s before delivery to the resin. The concentration of the activated monomers is 0.08 M during the couplings. Heteroselective solvation provides the highest coupling yields. Acetic anhydride is used as capping reagent followed by a piperidine wash. The protocol has been developed in a 5 mumol scale but is easily scaled up to 10-50 mumol scale syntheses on the automated synthesizer (ABI 433A).

Biopolymers↗

Impact of acquisition protocols and processing streams on tissue segmentation of T1 weighted MR images.

The segmentation of T1-weighted images into gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF) is a fundamental processing step in neuroimaging, the results of which affect many other structural imaging analyses. Variability in the segmentation process can decrease the power of a study to detect anatomical differences, and minimizing such variability can lead to more robust results. This paper outlines a straightforward strategy that can be used (1) to select more optimal data acquisition and processing protocols and (2) to quantify the impact of such optimization. Using this approach with multiple scans of a single subject, we found that the choice of a segmentation algorithm had the largest impact on variability, while the choice of a pulse sequence had the second largest impact. The data indicate that the classification of GM is the most variable, and that the optimal protocol may differ across tissue types. Therefore, the intended use of segmentation data should play a role in optimization. Examples are provided to demonstrate that the minimization of variability is not sufficient for optimization; the overall accuracy of the approach must also be considered. Simple volumetric computations are included to illustrate the potential gain of optimization; these results show that volume estimates from optimal pathways were on average three times less variable than estimates from suboptimal pathways. Therefore, the simple strategy illustrated here can be applied to many studies to optimize tissue segmentation, which should lead to a net increase in the power of structural neuroimaging studies.

Adult↗

Loss of chromosome 11 and 11 p/q imbalances in bladder cancer detected by fluorescence in situ hybridization.

To identify chromosomal imbalances in non-diploid transitional-cell carcinoma (TCC) of the bladder we performed double-target in situ hybridization (FISH), using the centromeric probe for chromosome 11 together with 2 cosmid probes located on the 11p and 11q arm in the proximity of the telomere. The FISH protocol was optimized to ensure a highly efficient and reproducible detectability of all 3 targets. As a consequence, it was possible to calculate ratios between the number of spots obtained with cosmid and centromere probes. Furthermore, the number of chromosomes 11 present was compared with the DNA index and the chromosome ploidy as obtained with other chromosome centromere probes. In this study we found that: (i) in 54 diploid TCCs a monosomy for chromosome 11 was detected in only one case; (ii) chromosome 11 was completely lost in 9 of 16 non-diploid TCCs; (iii) in 8 of these 16 non-diploid tumors an imbalance was observed between the 11p and 11q arm, in 4 of these cases a complete loss of chromosome 11 being observed in addition; (iv) the copy number counted for 11q was always identical to the 11 centromere number, except in one case, indicating a loss of 11p in the cases with imbalances. In total, 13 of 16 non-diploid TCCs (81%) showed either a loss of a complete chromosome 11, of (part of) the 11p arm, or both. Therefore we concluded that during tetra- or aneuploidization in TCCs, (part of) chromosome 11 is lost. In addition, our results indicate that under-representation of chromosome 11p occurs in the majority of the tumor cells, supporting the idea that loss of these sequences is an important step in the development of TCC.

Chromosomes, Human, Pair 11↗

Telophase enucleation: an improved method to prepare recipient cytoplasts for use in bovine nuclear transfer.

The enucleation of oocytes to be used as host cytoplasts for embryo reconstruction by nuclear transfer is an important limiting step when cloning mammals. We propose an enucleation technique based on the removal of chromatin after oocyte activation, at the telophase stage, by aspirating the second polar body and surrounding cytoplasm. In a preliminary experiment to determine an optimal activation protocol, oocytes were matured for 26 and 30 hr and exposed for 5 min to 7% ethanol and/or for 3 hr at either 25 or 4 degrees C. Relative to most activation treatments tested, oocytes matured for 30 hr and exposed to ethanol alone showed highest activation rates, as determined by low levels of H1 kinase activity within 90 min from exposure and high pronuclear formation (82%) after 12 hr of culture. No synergistic effect on activation rates was observed when oocytes also were exposed to reduced temperature after ethanol treatment. Microsurgical removal of the telophase-stage chromatin in a small volume of cytoplasm adjacent to the second polar body was significantly more effective in enucleating than aspiration of a larger cytoplasm volume surrounding the first polar body of metaphase-arrested oocytes (98% versus 59%; P < 0.01). Moreover, compared with a nuclear transfer protocol based on enucleation of metaphase-arrested oocytes followed by aging and cooling, more (38% versus 16%; P < 0.001) and better-quality blastocytes (126 versus 84 nuclei per blastocyst; P < 0.02) were obtained from embryos reconstructed using the telophase procedure. Higher development potential of embryos reconstructed by the telophase procedure may be attributed to (1) the selection of oocytes that activate and respond by extruding the second polar body, (2) avoiding the use of DNA dyes and ultraviolet irradiation, and (3) the limited removal of cytoplasm during enucleation. The ease with which telophase enucleation can be performed is likely to render this technique widely useful for research and practice on mammalian cloning.

Age Factors↗

Detection of calcium ionophore induced membrane changes in dog sperm as a simple method to predict the cryopreservability of dog semen.

The sensitivity of dog sperm cells for extracellular Ca(2+)/Ca(2+)-ionophore challenge was compared to the detrimental effects of an optimized freeze/thawing protocol. Three sperm-rich fractions of ejaculates from 9 dogs were obtained, and one aliquot of each ejaculate was washed in a modified Tyrode's medium (HBT containing 0.1 mM Ca(2+)), without (control sample) and with 2.5 microM Ca(2+)-ionophore (induced sample) and incubated for 60 min at 38 degrees C in humidified atmosphere. Another aliquot from the same semen fractions was diluted, washed in a Tris buffer, and packed into 0.5-ml straws with a Tris buffer containing 7.5 vol % glycerol. The samples were stored for 1 week in liquid nitrogen after a computer-driven three-step freeze protocol and subsequently thawed for 50 sec in a 37 degrees C water bath and reconstituted into HBT. The acrosome integrity was determined using fluorescein-conjugated peanut agglutinin (PNA-FITC) as an acrosomal marker, while the vitality of the sperm cells was simultaneously assessed with the membrane impermeable DNA supravital stain ethidium homodimer 1 (EthD-1) using fluorescence microscopy and flow cytometry. The motility of frozen/thawed sperm samples was evaluated by microscopic as well as computerized motility analyses. Remarkably, the percentage sperm cells that underwent acrosome reactions induced by Ca(2+)-ionophore correlated very positively (r = 0.93) with the amount of acrosome damage observed in cryopreserved sperm samples. Furthermore, the degree of cellular damage induced by Ca(2+)-ionophore treatment correlated very negatively (r = -0.99) with the relative amount of sperm cells that remained motile after cryopreservation. Such clear correlations between Ca(2+)-ionophore induced acrosome reaction and motility parameters for frozen/thawed dog sperm cells were not found, suggesting that the generation of acrosome leakage and sperm immotility are two independent detrimental processes occurring during cryopreservation. From these results it can be concluded that Ca(2+)-ionophore treatment followed by simultaneous determination PNA-FITC and EthD-1 staining can be used to predict the cryopreservability of ejaculates from individual dogs used as donors.

Acrosome Reaction↗

Separation and characterization of barley (Hordeum vulgare L.) hordeins by free zone capillary electrophoresis.

Extraction conditions, separation conditions, and capillary rinsing protocols were optimized for the separation of barley hordeins by free zone capillary electrophoresis. Stable hordein extracts were obtained with a single 5 min extraction after the albumins and globulins were removed. Hordeins had to be reduced for optimal resolution. Optimum separation conditions for hordein separations were 100 mM phosphate-glycine buffer containing 20% acetonitrile and 0.05% hydroxypropylmethylcellulose. The addition of zwitterionic sulfobetaine detergents containing hydrocarbon tails of eight and ten carbons slightly improved the resolution of the separations, but not enough to warrant their use on a routine basis. The migration positions of the hordein subclasses were determined by two- dimensional reversed-phase high-performance liquid chromatography x free zone capillary electrophoresis mapping. The hordein subclasses formed clusters similar to those of wheat gliadins. Separation-to-separation repeatability was good, with migration time relative standard deviations < 1% for a 15-run period. For routine discrimination of cultivars, a 2 min post-separation rinse with 500 mM acetic acid was necessary to prevent protein build-up on the capillary walls. An example of successfully differentiating barley cultivars using this technique is shown.

Chromatography, High Pressure Liquid↗

Improved survival from acute lymphoblastic leukemia in adolescents and adults.

Nineteen adult patients with acute lymphoblastic leukemia were treated with combination chemotherapy to induce remission in the period from 1971 to 1979. Those patients achieving remission received intensive post-remission therapy with central nervous system (CNS) prophylaxis, followed by two-drug maintenance therapy, and reinduction courses of chemotherapy every six months. Remissions were achieved in 17 of the 19 patients (89%). Twelve patients (63%) are alive, 11 currently in complete remission. Two patients who experienced relapses in recent months have successfully undergone transplantation with allogeneic marrow from sex-matched, HLA-compatible sibling donors. The median survival and median duration rates of first remissions have not yet been reached, but to date are 36+ months and 29+ months, respectively with a predicted five-year survival rate of 61%. These results not only are significantly better than those achieved in the years 1968 to 1971 in our institution, but also are superior to others reported in the world medical literature. The combination of optimal treatment protocols with allogeneic marrow transplantation for patients with poor prognoses is expected to improve the survival of adult patients even further in the next decade.

Adolescent↗

Rapid detection by fluorescent multiplex PCR of exon deletions and duplications in the C1 inhibitor gene of hereditary angioedema patients.

Hereditary angioedema (HAE) is due to a variety of defects in the C1 inhibitor gene (C1NH gene), including approximately 20% of partial deletions/duplications whose boundaries are usually within Alu repeats. To ensure complete molecular characterization of C1 inhibitor deficiencies a fluorescent multiplex assay was constructed to amplify simultaneously five exons of C1NH and an exon of the BRCA1 gene. PCR protocols were optimized for these amplicons (size range between 300 and 700 bp). Forward and reverse chimeric primers that carry strand-specific 5' tags of 16 nucleotides were used to ensure similar levels of PCR products for each amplicon in the multiplex. Data were analyzed by superposing fluorescent profiles of test and control DNA and by visually comparing the normalized peak levels of corresponding amplicons, rather than by calculating the ratios of peak areas. Tests on a collection of known defects, including five different Alu-mediated deletions and a partial duplication have validated this approach. In a study of 19 sporadic cases of HAE, of which four had failed to reveal mutations upon screening all exons by fluorescent chemical cleavage, three de novo deletions were diagnosed by using this multiplex PCR approach: a deletion of exon 4, a deletion of exons 5 and 6, and an apparently complete gene deletion. Besides being suitable for the initial DNA screening of the C1NH gene in HAE patients prior to screening for point mutations, this method can be easily adapted to complex genes for the screening of rearrangements.

Angioedema↗

Dendrimer-activated solid supports for nucleic acid and protein microarrays.

The generation of chemically activated glass surfaces is of increasing interest for the production of microarrays containing DNA, proteins, and low-molecular-weight components. We here report on a novel surface chemistry for highly efficient activation of glass slides. Our method is based on the initial modification of glass with primary amino groups using a protocol, specifically optimized for high aminosilylation yields, and in particular, for homogeneous surface coverages. In a following step the surface amino groups are activated with a homobifunctional linker, such as disuccinimidylglutarate (DSG) or 1,4-phenylenediisothiocyanate (PDITC), and then allowed to react with a starburst dendrimer that contains 64 primary amino groups in its outer sphere. Subsequently, the dendritic monomers are activated and crosslinked with a homobifunctional spacer, either DSG or PDITC. This leads to the formation of a thin, chemically reactive polymer film, covalently affixed to the glass substrate, which can directly be used for the covalent attachment of amino-modified components, such as oligonucleotides. The resulting DNA microarrays were studied by means of nucleic acid hybridization experiments using fluorophor-labeled complementary oligonucleotide targets. The results indicate that the novel dendrimer-activated surfaces display a surface coverage with capture oligomers about twofold greater than that with conventional microarrays containing linear chemical linkers. In addition, the experiments suggest that the hybridization occurs with decreased steric hindrance, likely a consequence of the long, flexible linker chain between the surface and the DNA oligomer. The surfaces were found to be resistant against repeated alkaline regeneration procedures, which is likely a consequence of the crosslinked polymeric structure of the dendrimer film. The high stability allows multiple hybridization experiments without significant loss of signal intensity. The versatility of the dendrimer surfaces is also demonstrated by the covalent immobilization of streptavidin as a model protein.

Autoradiography↗

Pulmonary artery catheters for adult patients in intensive care.

BACKGROUND: Pulmonary artery catheterization was adopted about 30 years ago and widely disseminated without rigorous evaluation as to whether it benefited critically ill patients. The technique is used to measure cardiac output and pressures in the pulmonary circulation to guide diagnosis and treatment. Clinicians believe these data can improve patients' outcomes, even in the absence of consensus about the specific interpretation of the data. OBJECTIVES: To assess the effect of pulmonary artery catheterization on mortality and cost of care in adult intensive care patients. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2, 2006); MEDLINE (all records to April 2006); EMBASE (all records to April 2006); CINAHL (all records to April 2006) and reference lists of articles. We contacted manufacturers and researchers in the field. SELECTION CRITERIA: We included all randomized controlled trials in adults, comparing management with and without a pulmonary artery catheter (PAC). DATA COLLECTION AND ANALYSIS: We screened the titles and abstracts of the electronic search results and obtained the full text of studies of possible relevance for independent review. We determined the final results of the literature search by consensus between the authors. We did not contact study authors for additional information. MAIN RESULTS: We identified 12 studies. Mortality was reported as hospital, 28-day, 30-day, or intensive care unit. We considered studies of high-risk surgery patients (eight studies) and general intensive care patients (four studies) separately for the meta-analysis. The pooled odds ratio for the studies of general intensive care patients was 1.05 (95% confidence interval (CI) 0.87 to 1.26) and for the studies of high-risk surgery patients 0.99 (95% CI 0.73 to 1.24). Of the eight studies of high-risk surgery patients, five evaluated the effectiveness of pre-operative optimization but there was no difference in mortality when these studies were examined separately. Pulmonary artery catheterization did not affect intensive care unit (reported by 10 studies) or hospital (reported by nine studies) length of stay. Four studies, conducted in the United States, measured costs based on hospital charges billed to patients, which on average were higher in the PAC groups. AUTHORS' CONCLUSIONS: To date, there have been two multi-centre trials of the effectiveness of PACs for managing critically ill patients admitted to intensive care, although only one was adequately powered. Efficacy studies are needed to determine optimal management protocols and patient groups who could benefit from management with a PAC.

Adult↗

Time-resolved fluorescence imaging for quantitative histochemistry using lanthanide chelates in nanoparticles and conjugated to monoclonal antibodies.

Tissue and cell examinations have a potential to produce extremely valuable information about antigen quantities in samples. Using currently available methods, a truly quantitative analysis is nearly impossible. We have previously shown that immunohistochemical (IHC) detection of prostate-specific antigen and human glandular kallikrein from prostatic tissue, together with time-resolved fluorescence imaging (TRFI), is a suitable method for obtaining quantitative data from biological samples and that the signal response is linear. In this paper we show that Eu-chelate containing particles in the nanometer range are suitable labels for quantitative IHC. Even single nanoparticle molecules can be detected by TRFI and the signals measured can be readily quantitated. The signal intensity correlates very well with the amount of bound label, and the use of nanoparticles could markedly improve the sensitivity of quantitative IHC methods. TRFI provides a powerful tool for providing quantitative data about antigens or transcripts in tissue sections or cultured cells. It is also of major importance in standardization and optimization of protocols for fixation and tissue preparation, including antigen retrieval methods.

Animals↗