Lung to blood passage of albumin and a nona-peptide after intratracheal instillation in the young developing pig

The passage via the lower respiratory tract of the macromolecule, bovine serum albumin (BSA, mol. wt = 67000) and the nonapeptide, l-deaminocysteine-8-d-arginine vaso-pressin (dDAVP, mol. wt = 1067), was assessed for 240 h after intratracheal instillation in young, developing pigs. The plasma levels of immunoreactive BSA increased with time, reaching a maximum between 36–86 h after instillation, and the main portion of BSA in plasma appeared intact, as assessed by crossed immunoelectrophoresis. The dDAVP levels reached a maximum after 1–3 h. The time to reach maximal plasma levels increased with the age of the pig for BSA, while no such effect was observed for dDAVP. The total lung passage, as calculated by dividing the area under the plasma level-time curve obtained after intratracheal instillation with that obtained after intravenous administration (elimination curve), showed no significant differences with age for BSA (21.8 ± 90% in the newborn, 15.1 ± 8.0% in the 2-day-old and 16.1±4.2% in the 70-day-old pigs). For dDAVP, a significant decrease in the total passage was obtained with age, from 74.6 ± 9.4% in the newborn pigs to 44.1 ± 13.3%, in the 2-day-old pigs (P < 0.001), and to 23.6 ± 7.1% (P< 0.01) in the 70-day-old pigs. The study showed that the marker molecules, BSA and dDAVP, passed over the porcine lung into the blood circulation in high amounts, apparently inversely related to their molecular size. The total lung passage of dDAVP, but not that of BSA, was affected by changes with age, indicating that these two markers might traverse the lung epithelium via different routes that are differently affected during postnatal development.     

Anxiety in adolescents born preterm or with very low birthweight: a meta‐analysis of case–control studies

Aim To determine if adolescents who are born very preterm (<32wks; of gestation) and/or with very low birthweight (VLBW; <1500g) have a higher risk of experiencing clinically significant anxiety problems. Method We used a systematic review and meta‐analysis. We searched the databases ISI Web of Knowledge, PubMed, PsycNET, Educational Resources Information Center (ERIC), Latin American and Caribbean Literature on the Health Sciences (LILACS), and Virtual Health Library (VHL) with equivalent search expressions (from the databases’ inception to June 2011). Also, we screened reference lists of identified articles. We selected case–control studies of adolescents 11 to 20 years old who were very preterm/VLBW and had a matched reference group born at term with normal birthweight that reported a validated anxiety outcome measure. For data extraction, two authors independently reviewed titles, abstracts, and full articles identified through the searches. Subsequently two authors independently extracted data. Results We included six studies with 1519 adolescents (787 very preterm/VLBW, 732 comparisons). The general risk of developing clinically significant anxiety problems was nearly doubled (p<0.05) in the very preterm/VLBW population (OR 2.27, 95% confidence interval 1.15–4.47). The overall prevalences were 9.9% in the very preterm/VLBW group and 5.5% in the comparison group. Interpretation Those born very preterm/VLBW have an increased risk of developing clinically significant anxiety problems in adolescence.     

The porcine bronchial artery: surgical and angiographic anatomy

The pig is often used in experimental studies on the significance of bronchial artery circulation, but the anatomy of this artery is only poorly described. The purpose of this study was to improve the anatomical basis for experimental studies on the porcine bronchial artery circulation. The origin of the artery from the aorta is described in 32 pigs. Heart–lung blocks were perfused with saline and removed in 16 pigs, and the broncho-oesophageal orifice was identified and cannulated. In these 16 specimens the intrapulmonary ramification was studied by angiography, and the extrapulmonary distribution and supply area by injection of Evans Blue. The broncho-oesophageal artery originated from the aorta as a single trunk in 91%. Angiography showed that each principal bronchus was accompanied by 2 bronchial artery branches far into the lung parenchyma. The central branching pattern of the artery between the aorta and the principal bronchi was divided into 3 subtypes. Evans Blue showed communication with the whole mediastinum. The anatomical relations are described. It is concluded that the broncho-oesophageal artery divides to follow each bronchus with 2 bronchial branches. A nomenclature for these branches is suggested. The pig anatomy is suited for experimental investigations on the bronchial circulation.     

Turbulent Stresses Downstream of Porcine and Pericardial Aortic Valves Implanted in Pigs

Because late valve-related complications such as hemolysis and thromboembolic events are considered related to flow disturbances caused by the inserted valve, velocity fields downstream of aortic valve prostheses were studied in pigs. Acute hemodynamic evaluation of size 25-mm porcine and pericardial aortic valve prostheses 1 diameter downstream of the valve ring was performed using dynamic three-dimensional visualization of velocity profiles and spatial distribution of turbulence. Point blood velocity signals obtained with a 1-mm hot-film anemometer needle probe were used to compute Reynolds normal stresses (RNS) by calculation of the turbulent velocity energy of the axial velocity component in the systole. The porcine valves caused a skewed velocity and turbulence profile revealing mean spatial systolic RNS at 70 nm-2 +/- 35 nm-2 (+/- SD). The spatial maximum RNS was 275 +/- 139 nm-2. Corresponding values for the pericardial valves were 20 +/- 11 nm-2 and 72 +/- 46 nm-2. The pericardial valves revealed plug-shaped velocity profiles and turbulent profiles with slightly higher RNS values at the stent posts. From a hemodynamic point of view, these acute studies indicate superiority of the pericardial valves compared to the porcine valves. The turbulent stresses found in this study are of a magnitude that may cause blood corpuscular and endothelial damage.     

Progressive Pulmonary Fibrosis Complicating Cyclophosphamide Therapy

ABSTRACT. Stentoft J (Department of Internal Medicine and Haematology, Aalborg Hospital, Aalborg, Denmark). Progressive pulmonary fibrosis complicating cyclophosphamide therapy. A 26-year-old woman with extra-pulmonary Wegener's granulomatosis was treated with cyclophosphamide for 3.25 years, cumulated dose of 91 g. Six months before cessation of therapy discrete radiological signs of apical fibrosis appeared. The changes were progressive regardless of discontinuation of cyclophosphamide and led to severe restrictive ventilatory defect.     

Smoking habits in relapsed subjects from a smoking cessation trial after one year

Reports of smoking cessation studies often claim that many relapsed subjects reduce their smoking. We investigated the smoking habits of relapsers 1 year after quitting in a smoking cessation trial using nicotine or placebo patches. All 289 participants in that study were summoned to a 1-year follow-up visit–148 (57%) of 259 relapsers attended, as did all 30 sustained abstainers. Fewer than 1% of the subjects had quit spontaneously after the primary relapse. Daily cigarette consumption, standard nicotine yield per cigarette, saliva cotinine concentration, expired carbon monoxide level and two nicotine dependency scales were assessed at entry and at the 1-year follow-up. In five of these six smoking-related characteristics, there was a small but significant mean reduction of 7%-27%. A significant weight gain of 0.5 ± 2.9 kg (mean ± SD) was recorded in the relapsers compared with 4.8 ± 4.2 kg for abstainers (p < 0.001). It is concluded that smoking habits in relapsers are relatively unchanged, and thus the most important outcome measure in smoking cessation trials is abstinent subjects.     

An Animal Model for the Study of the Function of Pregnancy-Specific Beta1 Glycoprotein and Pregnancy Zone Protein: A Review*

ABSTRACT: Two pregnancy-associated murine proteins, PAMP-1 and PAMP-2, have been found to be immunologically cross-reacting analogues to the human proteins pregnancy zone protein (PZP) and pregnancy-specific beta₁-glycoprotien (SP-1), respectively. In this study, the physiochemical and biological properties of the proteins are compared and the effect on pregnancy of administration of monospecific antibodies against the proteins is reported.