Static lung volumes and airway resistance reference values in healthy adults

Background and objective: The assessment of static lung volumes and airway resistance is a frequently performed diagnostic procedure and considered as an important tool in medical surveillance to detect pulmonary diseases. The objectives of the study are to establish reference equations for body plethysmographic parameters in a representative adult population across a wide age range and to compare the normative values from this sample with previous ones. Methods: Body plethysmography was applied in 1809 participants (885 males) of a cross‐sectional, population‐based survey (Study of Health in Pomerania). Individuals with cardiopulmonary disorders and/or a pack‐year smoking history >10 years and participants with a body mass index >30 kg/m² were excluded. In total, 686 healthy individuals (275 males) aged 25–85 years were assessed. Results: Prediction equations for both genders were established by quantile regression analysis taking into account the influence of age, height and weight. Conclusions: The study provides a novel set of prediction equations for static lung volumes and airway resistance obtained using body plethysmography. Compared with our findings, existing equations underestimated some normal values. The results emphasize the need for up‐to‐date reference equations.     

First‐In‐Man Experience With a New 7F Vascular Closure Device (EXOSEAL™): The 7F ECLIPSE Study

Objective: This feasibility study examined safety and effectiveness of the new EXOSEAL? Vascular Closure Device (VCD) designed to promote hemostasis and early ambulation after percutaneous procedures. Background: Most VCDs currently approved by the United States FDA have been associated with significantly shorter time‐to‐hemostasis (TTH) and time‐to‐ambulation (TTA) compared to standard manual or mechanical compression, but their ease of use, patient comfort during deployment, and safety profiles are variable. Methods: Patients underwent diagnostic or interventional procedures using 7F introducer sheaths. Primary safety endpoint was the 30‐day combined rate of access‐related complications and primary effectiveness endpoints were TTH and TTA. Results: Sixty patients were enrolled prospectively (mean age 63.3 ± 11.3 year, 17% diabetics). Device and procedural success was achieved in 92% and 93%, respectively. Mean TTH and TTA was 3.2 ± 3.0 minutes and 3.0 ± 6.2 hours, respectively. No deaths or serious access‐related adverse events occurred. A ≥6 cm access‐site hematoma was the only adverse event, observed in 3 patients. Conclusions: Use of the 7F EXOSEAL? VCD was associated with short TTH and TTA, as well as low rates of procedural and 30‐day access‐related complications. (J Interven Cardiol 2012;25:518–525)     

A Technical Approach to Optimized Atrial Recognition in the ICD:

Present-day ICD systems offer the possibility to reconstruct an intrathoracic 6-lead ECG (IT-ECG), using the defibrillator coils in the right ventricle and superior vena cava and the left-laterally positioned ICD as electrodes according to Einthoven and Goldberger. The aim of this study was to assess the feasibility of (1) automated P wave recognition in the IT-ECG without an additional atrial electrode as the basis of AV synchronous ventricular pacing (VDD) and for improved differentiation between supraventricular tachyarrhythmias and, (2) the automated detection of pacing evoked atrial potentials (EAP) in dual chamber ICDs as the basis for atrial "autocapture " pacing systems. In 27 patients during ICD implanation intraoperatively, the IT-ECG was digitally recorded. A recently established algorithm for automatic P wave and EAP detection correctly identified 1,663/1,672 (99.5%) P waves (oversensing rate 0.6%) and 543/554 (98.0%) EAP (no oversensing). During subthreshold atrial stimulation, 405/412 (98.3%) P waves were correctly identified (oversensing due to pacemaker spikes,   n = 421   , without subsequent EAP, 1.9%,   n = 8   ). During stimulated ventricular tachycardia in 26/27 patients retrograde P wave or AV dissociation were identified. The 6-lead IT-ECG, easily implementable in ICD systems, is a diagnostic tool providing reliable information about atrial activation, serving as a basis for VDD pacing in single chamber ICD systems, allowing reliable EAP recognition that enables atrial "autocapture " pacing in dual chamber ICDs, and improves the differentiation between supraventricular and ventricular tachycardia. (PACE 2003; 26[Pt. I]:1472–1478)     

A novel isotonic‐balanced electrolyte solution with 1% glucose for perioperative fluid management in children‐ an animal experimental preauthorization study

Background: The recommendations for perioperative maintenance fluid in children have been adapted from hypotonic to isotonic electrolyte solutions with lower glucose concentrations (1–2.5% instead of 5%) to avoid hyponatremia or hyperglycemia. Objective: The objective of this prospective animal study was to determine the margin of safety of a novel isotonic‐balanced electrolyte solution with 1% glucose (BS‐G1) in comparison with normal saline with 1% glucose (NS‐G1) in the case of accidental hyperhydration with a focus on acid–base electrolyte balance, glucose concentration, osmolality and intracranial pressure in piglets. Methods: Ten piglets (bodyweight 11.8 ± 1.8 kg) were randomly assigned to receive either 100 ml·kg^?1 of BS‐G1 or NS‐G1 within one hour. Before, during and after fluid administration, electrolytes, lactate, hemoglobin, hematocrit, glucose, osmolality and acid–base parameters were measured. Results: Unlike BS‐G1, administration of NS‐G1 produced mild hyperchloremic acidosis (base excess BS‐G1 vs NS‐G1, baseline 1.9 ± 1.7 vs 2.9 ± 0.9 mmol·l^?1, study end 0.2 ± 1.7 vs ?2.7 ± 0.5 mmol·l^?1, P < 0.05, chloride BS‐G1 vs NS‐G1 baseline 102.4 ± 3.4 vs 102.0 ± 0.7 mmol·l^?1, study end 103.4 ± 1.8 vs 109.0 ± 1.4 mmol·l^?1P < 0.05). The addition of 1% glucose led to moderate hyperglycemia (P < 0.05) with a concomitant increase in serum osmolality in both groups (P < 0.05). Conclusion: Both solutions showed a wide margin of safety in the case of accidental hyperhydration with less acid–base electrolyte changes when using BS‐G1. This novel solution could therefore enhance patient’s safety within the scope of perioperative volume management.     

Acucise endopyelotomy: A technique with limited efficacy for primary ureteropelvic junction obstruction in adults

AIM: To retrospectively evaluate the ef fi cacy of Acucise endopyelotomy in a series of patients with primary ureteropelvic junction obstruction (UPJO). METHODS: Twenty-four patients with a symptomatic primary UPJO underwent Acucise endopyelotomy. Patients with high-grade hydronephrosis and/or poor renal function were excluded. Patients were followed by ultrasound imaging, intravenous urography, diuretic renography, and clinical review. RESULTS: The overall success rate was 58% (14/24 patients), with a median follow up of 32 months. Of the ten patients in whom Acucise endopyelotomy failed, seven underwent open pyeloplasty, one required nephrectomy, and two received a permanent ureteral stent. A poor outcome was noted in patients without perioperative extravasation. CONCLUSIONS: Our experience with Acucise endopyelotomy indicates that the success rate is lower than initially reported. Larger studies are needed to clarify the role of Acucise endopyelotomy in comparison with other techniques.     

Polymethylene spacer linked bis(A1a) peptides form modified β:-sheet structures

The adipoyl- and suberoyl-linked bis(Ala) peptides have an extended backbone between the two C^alpha; atoms in each molecule. They self-assemble, through intermolecular hydrogen bonds and stacking of parallel strands, into highly ordered modified β-sheet-like structures. Crystal data for adipoyl bis(A1a)diester are as follows: C₁₄H₂₄N₂)O₆, monoclinic space group P2₁, a = 4.900(1), b = 29.093(10), c = 6.021(2) Å, β= 104.20(2)?, R = 0.053 for 1100 data >3σ(F); for suberoyl bis(A1a)diester: C₁₆H₂₈N₂O₆, monoclinic space group P2¹, a = 4.887(2), b = 32.650(9), c = 6.004(2) Å; β= 103.79(3), R = 0.070 for 1065 data > 3σ.     

Bufuralol metabolism in human liver: a sensitive probe for the debrisoquine-type polymorphism of drug oxidation

The genetically controlled polymorphism causing decreased metabolism of debrisoquine is closely related to that of the metabolism of bufuralol and numerous other drugs and has important clinical consequences. A sensitive in vitro assay was developed which quantifies the production of 1'-hydroxy-bufuralol (carbinol) from bufuralol in human liver microsomes. Initial formation rates of carbinol suggested Michaelis-Menten kinetics with an apparent KM of 61 and 171 mumol l-1 and Vmax of 3.2 and 5.8 nmol mg-1 microsomal protein h-1 in two human liver samples. The Vmax in microsomes of thirty-two liver samples was 4.2 +/- 1.0 (SD) nmol carbinol mg-1 protein h-1. Metabolism of debrisoquine in vivo, as expressed by the 'metabolic ratio' of debrisoquine over 4-OH debrisoquine correlated (r = -0.65, P less than 0.01; n = 18) with carbinol production rate in microsomes in vitro. Microsomes of one individual identified as poor metabolizer of debrisoquine in vivo showed reduction of carbinol formation to 1.97 nmol mg-1 h-1. Mixing his microsomes with those of an extensive metabolizer resulted in additive formation of carbinol excluding mediation of the defect by a soluble inhibitor. These data support the concept of a primary defect in microsomal oxidation of bufuralol. The described assay offers a sensitive tool to investigate the molecular mechanism of the 'debrisoquine polymorphism'.     

Variability in the backbone conformation of cyclic pentapeptides

All the peptide bonds in cyclic(Gly-LPro-DPhe-Gly-LAla) are in the trans conformation; however, the peptide bond C₅'-N₁ is twisted by 19° from planarity (ω₅= - 161°). A Type II β-turn encompasses the LPro-DPhe residues. Carbonyl oxygens O₂, O₄ and O₅ are directed to the same side of the average plane through the backbone ring and they form hydrogen bonds with N₃, N₅ and N₁, respectively, in adjacent molecules in a stacked column where the adjacent molecules are related by one translational unit. The conformation of the backbone is different from that established in other molecules with the DLDDL chirality sequence. The P2₁ cell contains two molecules of C₂₁H₂₆N₅O₅ with a = 4.836(2) A, b = 18.346(8) A, c = 12.464(5) A and β= 100.05(4)°. The R factor for 1382 data with ¶F₀¶ > 1 ¶ is 7.0%.