Biomedical subjects

J Roman

Publications and source records attributed to J Roman.

113 records · Page 7Linked to original sources

PubMedDate not supplied

Coagulation, fibrinolytic and kallikrein systems in neonates with uncomplicated sepsis and septic shock.

This study evaluates the contact system, coagulation inhibitors and fibrinolysis in 23 full-term newborns with sepsis (8 with septic shock). The results were compared with a group of 20 healthy newborns. Blood samples were obtained at the time of clinical diagnosis and 3 days after the antibiotic therapy was started. The results showed that: severe infection was associated with activation of the contact system, depletion of anticoagulant proteins and elevation of C4b-binding protein levels. There was a shift in protein S to the complexed inactive form, and the thrombin-antithrombin complexes increased. These changes occurred in parallel to both activation and inhibition of fibrinolysis. These changes were more pronounced in the septic shock patients than in nonshock neonates. After therapy, this procoagulant state decreased among survivor patients while in those who died, the abnormalities in coagulation did not improve. Our study suggests that neonatal sepsis induces a hypercoagulable state that persists in nonsurvivor neonates despite a correct treatment.

Anti-Bacterial Agents↗

PubMedDate not supplied

Effects of calcium channel blockade on mammalian lung branching morphogenesis.

The bronchial tree is formed during the pseudo-glandular stage of lung development in a process termed lung branching morphogenesis. Coinciding with the period of lung branching morphogenesis is the appearance of spontaneous airway contractions, a phenomenon whose role in development remains unclear. In this study, an in vitro model of murine lung branching morphogenesis was used to examine the potential role of airway contractions in airway branching and lung growth. Spontaneous airway contractions of the proximal airways were observed in cultured murine lungs (obtained at 11 days of gestation) after 48 h in culture. Airway contractility was inhibited in a reversible manner by the voltage-dependent calcium channel blocker Nifedipine. Interestingly, long-term incubation of lung rudiments with Nifedipine not only prevented airway contraction, but also caused lung hypoplasia. The Nifedipine-treated hypoplastic lungs showed a normal branching pattern, suggesting that airway contractions and calcium channel function are not necessary for cleft formation directly. These observations suggest that calcium ion transport is necessary for development of airway contractions and for normal progression of lung growth.

Animals↗

PubMedDate not supplied

Fibronectin and fibronectin receptors in lung development.

Fibronectin (FN) is a cell adhesive extracellular matrix protein highly expressed in developing lungs. Although the role of FN in lung development remains to be elucidated, several observations suggest that it plays important roles in many developmental processes. In vitro, FN can affect the migration, proliferation, differentiation, and even apoptosis of various cell types, all considered necessary for organogenesis. The cellular effects of FN are primarily mediated by cell surface heterodimeric receptors of the integrin family. Ligand binding to these receptors triggers the activation of intracellular signaling events responsible for alterations in gene transcription and, ultimately, cell function. Immunohistochemical analysis of embryos revealed increased deposition of FN during the pseudoglandular stage of lung development, coinciding with the period of branching morphogenesis. This observation, together with the strategic location of FN around developing airways predominantly at cleft sites, suggests a role in airways formation. This hypothesis is supported by studies showing that reagents capable of preventing FN-FN receptor binding inhibit branching morphogenesis in murine lung explants. Less is known about the potential role of FN in other aspects of lung development. However, in vitro studies suggest that FN may affect vessel formation, alveolar epithelial cell differentiation and lung growth and maturation.

Animals↗

PubMedDate not supplied

A comparison of verapamil and propranolol for the initial treatment of hypertension. Racial differences in response.

We compared verapamil and propranolol hydrochloride for monotherapy of hypertension. Verapamil lowered blood pressure (BP) more effectively than propranolol in black and white patients. Verapamil was equally effective in blacks and whites, whereas propranolol was more effective in whites. Heart rate was reduced by 6.0 beats per minute by verapamil, and by 13.6 beats per minute by propranolol. In blacks, verapamil lowered systolic BP 16.9 vs 8.1 mm Hg for propranolol; verapamil reduced diastolic BP 12.8 vs 8.6 mm Hg for propranolol. In whites, verapamil lowered systolic BP 19.0 vs 12.7 mm Hg for propranolol; verapamil reduced diastolic BP 16.7 vs 12.3 mm Hg for propranolol. Increases in systolic BP were observed in 22% and 3.4% of patients receiving propranolol and verapamil, respectively. The PR interval was increased from 163.5 to 174.9 ms for verapamil vs 160.3 to 164.4 ms for propranolol. Constipation (15%) and headaches (10%) were most frequent complaints for verapamil vs fatigue (18%) and dizziness (7%) for propranolol. Changes in blood biochemistry values were of small magnitude. We conclude that verapamil monotherapy is a safe and effective means of achieving BP control in patients with essential hypertension.

Adult↗

PubMedDate not supplied

The effect of leucotrofina and BSA (bovine serum albumin) antigen on the ontogenetical capacity of antibody generation in chicken.

Leucotrofina administration to chickens of two different ages (2,5 IU/chicken to 3 days old chickens, and 5 IU/individual to 21 days old chickens), associated with an antigen (1 / 1000 Bovine Serum Albumin) (0,25 ml, respectively 0.5 ml/animal in young and in older chickens) affected several blood serum parameters as: the antibodies concentration, the gamma-globulins, the total proteins, and the nitrogen of the free amino-acids content in a manner corresponding to the experimental model and to age the of the animals.

Aging↗