[Our experience in the thoracoscopic surgery of the tuberculous pleural effusions]. / Experienta noastra în chirurgia toracoscopica a colectiilor pleurale tuberculoase.

Pleural tuberculosis (TB) is most often treated by a pneumologist. Some cases require operative interventions and may represent a challenge for the thoracic surgeon. There are two specific problems regarding TB pleural effusions: 15-25% of them remain undiagnosed using the conventional methods of diagnosis (imaging, thoracentesis, percutaneous pleural biopsies) and have a tendency for the rapid production of dense adherences and loculations. The authors present their experience in the diagnosis and the treatment of tuberculous pleurisy by means of mini-invasive surgical techniques. The period of study was January 2001-December 2006. In that period, the authors performed 400 video-assisted surgical operations, representing 9% of all the operations carried out in the clinic (3833). The surgical indications were for diagnosis (pleural, pericardial, lung or lymph node biopsy) and for treatment (pleurisy, pleuro-pericarditis, empyema). The contraindications for VATS were the usual ones. 56 cases were diagnosed with pleuro-pulmonary tuberculosis (14% of the VATS). For 43 patients the first approach was strictly thoracoscopic (VATS), while for the rest of 13 we started directly through a minithoracotomy with video assistance. We had 7 conversions to minithoracotomies with video assistance from those 43 aforementioned patients. Minithoracotomy with video assistance was preferred in 13 cases as a primary approach. We used two-port approach in 30 cases and the three-port triangular approach was useful for 6 patients. In 4 cases the bidigital technique was used in order to achieve greater room for exploration. We experienced only one minor intraoperative complication. Our results are comparable to those reported by other authors. The main idea of this paper is that the advantages of VATS in the pathology of the tuberculosis are undeniable.

Structural and catalytic properties of L-alanine dehydrogenase from Bacillus cereus.

Alanine dehydrogenase from Bacillus cereus, a non-allosteric enzyme composed of six identical subunits, was purified to homogeneity by chromatography on blue-Sepharose and Sepharose 6B-CL. Like other pyridine-linked dehydrogenases, alanine dehydrogenase is inhibited by Cibacron blue, competitively with respect to NADH and noncompetitively with respect to pyruvate. The enzyme was inactivated by 0.1 M glycine/HCl (pH 2) and reactivated by 0.1 M phosphate (pH 8) supplemented with NAD+ or NADH. The reactivation was characterized by sigmoidal kinetics indicating a complex mechanism involving rate-limiting folding and association steps. Cibacron blue interfered with renaturation, presumably by competition with NADH. Chromatography on Sepharose 6B-CL of the partially renatured alanine dehydrogenase led to the separation of several intermediates, but only the hexamer was characterized by enzymatic activity. By immobilization on Sepharose 4B, alanine dehydrogenase from B. cereus retained 66% of the specific activity of the soluble enzyme. After denaturation of immobilized alanine dehydrogenase with 7 M urea, 37% of the initial protein was still bound to Sepharose, indicating that on the average the hexamer was attached to the matrix via, at most, two subunits. The ability of the denatured, immobilized subunits to pick up subunits from solution shows their capacity to fold back to the native conformation after urea treatment. The formation of "hybrids" between subunits of enzyme from B. cereus and Bacillus subtilis demonstrates the close resemblance of the tertiary and quaternary structures of alanine dehydrogenases from these species.

Catalytic properties of Sepharose-bound L-alanine dehydrogenase from Bacillus cereus.

(1) L-Alanine dehydrogenase from Bacillus cereus was purified by a two-step chromatographic procedure involving Cibacron-Blue 3G-A Sepharose 4B-CL, and Sepharose 6B-CL, and immobilized on CNBr-activated Sepharose 4B. (2) Following immobilization via two of the six subunits, L-alanine dehydrogenase retained 66% of the specific activity of the soluble enzyme. The affinity of the immobilized enzyme for NH4+, pyruvate and L-alanine, was not different to that of the soluble form. The Km of the Sepharose-bound L-alanine dehydrogenase for pyridine coenzymes was 6-8-times higher than in the soluble case. (3) The stability of L-alanine dehydrogenase towards urea or thermal denaturation was increased by immobilization. (4) The incubation at 37 degrees C for 24 h of the immobilized L-alanine dehydrogenase with 3 M NH4Cl/NH4OH buffer (pH 9) released 70% of the enzyme. The specific activity and the affinity of the 'solubilized' L-alanine dehydrogenase for the pyridine coenzymes was the same as that obtained with the original, soluble L-alanine dehydrogenase.

[Role of parainfluenza varuses in etiology of acute respiratory infections in children (serological diagnosis)]. / Rolul virusurilor paragripale în etiologia infectiilor respiratorii acute ale copilului (diagnostic serologic).

Serologic investigations carried out in 254 children admitted to a Clinic for Children for respiratory diseases, established a diagnosis of infection with parainfluenza virus in 19.2% of cases. The predominant age-group affected was 7--12 months and 0--6 months; the causative agent in most cases was parainfluenza type 3, followed by type 2 and then type 1. The role of parainfluenza viruses in the aetiology of laryngotracheobronchiectasis was confirmed, as well as their participation in the aetiology of pneumonia in infants. The results also showed the wide circulation of parainfluenza viruses in children and their outstanding contribution to respiratory diseases among hospitalized children within a period of four years.

[Serological studies of the role of the respiratory syncytial virus in acute respiratory diseases in children]. / Investigatii serologice privind participarea virusului respirator sincitial în îmbolnavirile respiratorii acute la copii

The presence of the syncytial respiratory virus was determined by CF in 281 children admitted with acute respiratory diseases between 15 Sept. 1971 and 30 Dec. 1973, using the Long antigen prepared in the "St. Nicolau" Institute of Virology, Bucharest. In 38 children (13.5%) a serologic diagnosis of infection with the syncytial virus was established; in the other cases of respiratory infection of different etiology, antibodies to the syncytial virus were found in low but constant titers in both serum samples. The presence of these antibodies in a high proportion of the children points to the wide circulation of the syncytial virus in the infantile population, with all its clinico-epidemiologic implications.