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The effect of doping MgB[sub 2] with carbon nanotubes on transition temperature, lattice parameters, critical current density and flux pinning was studied for MgB[sub 2-x]C[sub x] with x=0, 0.05, 0.1, 0.2, and 0.3. The carbon substitution for B was found to enhance J[sub c] in magnetic fields but depress T[sub c]. The depression of T[sub c], which is caused by the carbon substitution for B, increases with an increasing doping level, sintering temperature, and duration. By controlling the extent of the substitution and addition of carbon nanotubes we can achieve the optimal improvement on critical current density and flux pinning in magnetic fields while maintaining the minimum reduction in T[sub c]. Under these conditions, J[sub c] was enhanced by two orders of magnitude at 8 T and 5 K and 7 T and 10 K. J[sub c] was more than 10 000 A/cm2 at 20 K and 4 T and 5 K and 8.5 T, respectively. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Purpose: To characterize clinical outcomes of combined viscodilation of Schlemm's canal and collector channels and 360° trabeculotomy as a standalone procedure or combined with cataract surgery in eyes with mild to moderate open-angle glaucoma (OAG)., Methods: In this prospective case series, the OMNI glaucoma surgical platform (Sight Sciences, Menlo Park, CA) was utilized to perform the procedure either combined with phacoemulsification or as a standalone procedure. Changes from baseline in intraocular pressure (IOP) and IOP-lowering medications were evaluated through the first 12 months of a planned 24-month follow-up period., Results: Among 17 eyes of 15 subjects, mean IOP was reduced from 20.4 mmHg to 12.7-13.7 mmHg through 12 months of follow-up ( p  < 0.001 at every time point) and mean medications reduced from 2.5 to 0.1-0.6 ( p  < 0.001 at every time point). IOP reductions in eyes undergoing standalone surgery were approximately 2-4 mmHg greater at each time point compared to eyes undergoing surgery combined with phacoemulsification; this may be related to a higher baseline IOP in the former eyes (22.1 vs 18.5 mmHg). Six eyes developed hyphema, of which three required washout for elevated IOP on the first postoperative day; six additional eyes had IOP elevations that resolved with medical management., Conclusion: Viscodilation of Schlemm's canal and collector channels paired with ab interno trabeculotomy performed with a single integrated instrument (OMNI), whether as standalone or combined with phacoemulsification, effectively lowers both IOP and the need for IOP-lowering medications through 12 months of follow-up.

Aim: This is the first overview of practice patterns in endophthalmitis prevention after cataract surgery in Poland., Material and Methods: The study is based on a survey carried out in 33 centres performing cataract surgery in two provinces of Poland (a total of 8.8 million inhabitants, i.e. 23% of the entire country population). Approximately 39.000 cataract surgery procedures are performed in these regions annually, i.e. 20% of all cataract surgery procedures in Poland. The questionnaire-based survey focused on the following aspects: duration of preoperative antibiotic treatment, type of antiseptics, intraoperative administration of antibiotics and duration of postoperative antibiotic treatment., Results: All surveyed centres use povidone-iodine as antiseptic on the periocular skin and conjunctival sac, and perioperative topical antibiotics are adopted by most. Intracameral cefuroxime is increasingly used in endophthalmitis prevention., Conclusion: The methods of endophthalmitis prevention vary widely between ophthalmology departments and clinics in Poland, there is no scientific rationale for most preventive measures used and a further debate is needed among Polish ophthalmic surgeons on optimal practice patterns.

The antigenic-toxic complex of B. abortus isolated in the phenol phase of phenol/water system, is a lipopolysaccharide (LPS)-protein macromolecule. The specific side chain was isolated from this complex by means of pronase treatment and mild HCl cleavage, followed by fractionation on Sephadex. The side chain thus isolated lost its capacity to coat erythrocytes but not that of neutralizing antibodies, as shown in the hemagglutination inhibition test. Esterification of the side chain with lauryl sulfat restored its erythrocyte coating capacity. In view of transforming this haptene into an immunogen, it was attached to S. minnesota Re cells. Immunization of rabbits with this conjugate engendered the formation of antibodies that agglutinated B. abortus and B. melitensis cells as well. As the side chain could only be isolated from the smooth strain, it proves that a defect in the synthesis of this moiety gave rise to the rough Brucella mutant. In the latter fraction glucose, mannose and quinovosamine were identified. Fraction II separated on Sephadex was identified as the core polysaccharide, present in the preparation obtained from smooth and rough strain. In the core region 2-keto-3-deoxy-octonate, glucose, glucosamine (from the smooth but not from the rough strain) and protein were identified. Following the mild HCl hydrolysis, the lipid-protein moiety i.e. region 3, is also split off but without precipitating and, during the fractionation on Sephadex, it adsorbs onto the gel. The absence of beta-hydroxymyristic acid and glucosamine in Brucella lipid dissociates it from the enteric lipid A. In the LPS-protein's toxicity a major role has the protein present only in the smooth strain.

A four-times-recurring thoracal mesenchymoma is presented. Each tumor evolved for 2-5 years before resection, the general evolution of the case being of about 30 years. Histologically, the tumors, which involved the thoracal wall presented at the same time the predominating fibroblasto-fibrocytic structure sometimes forming whirls, different mesenchymal derivatives as vessels and angiomatous formations, osseous trabeculae, chondroblastic areas, and more or less dense zones with leiomyocytes sometimes forming myomatous and myofibromatous aspects. Mitoses and nuclear atypias were very rare. The diagnosis of benign recurring mesenchymoma of the thoracal wall and pleura is discussed.

The relationships between mesenchymal lung cell accumulations and reticulinic fibrillogenesis were analysed morphologically and quantitatively during the development of a viral infection in the rabbit lung, induced by intranasal administration of influenza A2 virus. Cells and fibrils accumulated in the alveolar walls and in the interlobular areas of the lung were counted during the evolution of the experiment and statistically analysed. A significant statistical correlation between lung cell accumulations and fibrillogenesis could be demonstrated during the development of viral lung fibrosis.

An experimental model of bronchiolar lesions was elaborated. It consisted of three intratracheal administrations in rabbits of 2 ml of a 3 per cent detergent solution, pH 2.5-3; the adequate development of the process was induced when the second injection was given 48 h after the first and the third on days 5-6. The induced process evolved during three phases: a) hypertrophy with hyperfunction of Clara cells, cell beheading by apo- and merocrinia and denudation of basement membranes; b) lesions of subepithelial components, mainly of capillaries, with granulative response and restructuration of the peribronchiolar tissue, and c) tardy regenerative response of epithelial cells, sometimes with neoformation of bronchioli. The morphometric analysis of this experimental process asserted the validity of the model which led to damages involving at less 70 per cent of the bronchioli (under 200 epithelial nuclei on a circumferential section) and of the small bronchi (with 200-500 epithelia nuclei); the other small and large bronchi were never involved. The morphometric analysis also showed the relations of the intervals between injections to the lesional intensity and stereotyping.

Three experimental fibrosing granulomatous processes of the lung (pulmonary granulomas induced by complete Freund adjuvant, viral pneumonitis induced by the A2 influenza virus, and tuberculosis induced in animals exposed to tobacco smoke) were produced in rabbits and the results confronted in view of establishing some relationships between mesenchymal cell accumulations, reticulin fibrillogenesis, and the enzymic activities of proline-oxidase (PO) and of hydroxyproline-2-epimerase (HEP), enzymes intervening in the control of hydroxyproline incorporation in the procollagen molecule. Histopathologic, histochemical and histoenzymic methods, quantification of cells and fibrils, statistical analyses, including the regression lines method, were used. The confrontation of the three processes made obvious that the cell accumulation invariably preceded the fibrillogenetic process, that the immune nature of the process was accompanied by larger cell accumulations than the non-immune one, that between cell accumulations and fibrillogenesis there existed highly significant correlations, and that the increase of the enzymic activities of proline-oxidase and of hydroxyproline-2-epimerase always accompanied these tissular changes, being topographically coincident with them (interlobular areas, alveolar walls).

The present investigation was designed to the study, in rabbits, of morphologic and enzymatic pulmonary alterations produced by tobacco smoke and the course of tuberculosis under these conditions. The histologic examination revealed muciparous hyperplasia and pavementing metaplasia of the bronchic epithelium, accompanied by interstitial cellular reactions, reticulin, fibrilogenesis, atelectasis, emphysema and marked debility of the animals. In the animals treated with tobacco smoke the tuberculous lesions were very extensive and had an exudative-necrotic character. Under the influence of chemotherapy, applied during three months, reorganization of the lesions was reduced in comparison to the controls and an intense bacteriological activity persisted.

The enzymic activity of acid alkaline phosphatases, of alanyl- and leucine-aminopeptidases, of beta-galactosidase and beta-glucuronidase, and of Tween-60-esterase was tested in the rabbit lung tissue during the following experimental processes: a) the sensitization with Freund adjuvant containing PPD and challenge of the delayed hypersensitivity reaction to PPD), b) the sensitization with gamma-globulin in Freund adjuvant, c) the pulmonary Arthus reaction, d) the lung granulomas induced by intravenous administration of Freund adjuvant containing heterologous lung proteins, e) the tuberculosis and silicotuberculosis under the influence of tuberculostatics. A metabolic intensification expressed by a marked increase of the tested hydrolytic enzymes was observed comparatively with controls in all these immune, granulomatous and inflammatory processes experimentally induced in the lung. The morphologic substrate of this behaviour was represented by the numerous cell proliferation and differentiations of the reticulomacrophagic type occurring during these experimental processes under the stimulation of antigenic elicitors. The latter also induced an increase of the lysosome-formation as submicroscopic site of these hydrolytic enzymes.

The development of several cases of miliary tuberculosis in infants aged 3--4 months, born in the same maternity led to an epidemiological investigation. On this occasion it was discovered that one of the patients that had been discharged immediately after delivery had pulmonary granulia a monthlater. The immature newborn was left in the maternity and died after one month with a diagnosis of "pulmonary microabscesses". The histopathologic examination of the lungs showed the presence of necrotic foci without any cellular reaction. Five months after the death of the infant a new examination of a pulmonary fragment was performed and Ziehl-Neelsen staining evidenced a large number of acido-resistant bacilli filling the lung alveoles. It was shown in this way that the infant with tuberculosis was the primary source of infection. All the 8 children that had developed the disease had been hospitalized in the same ward with the sick child. The transmission of the bacilli was done indirectly, through the feeding tubes that had not been sufficiently serilised, and the penetration ronte was the digestive tract. In two cases an otic primary focus was discovered and in one case an intestinal one was found on necropsy.

Three cases of eosinophilic granuloma of the lung were histopathologically analyzed on surgical materials (two resections and lung biopsy). The analysis insisted upon the cell components of pulmonary lesions, histiocytic and eosinocytic accumulations involving lobular air spaces, alveolar walls and interlobular areas, and forming bullae by histiocytic enzymic activity and lipid dysmetabolism; the fibrotic evolution of the lesions varied from case to case. The lesional histogenesis is discussed in the light of recent electronmicroscropic, histochemical and immunopathological data, stress being laid upon the local influence on the development of the process.

The prolonged exposure to formaldehyde induces in the rabbit lung reactional and dystrophic changes involving the intrapulmonary bronchi, the bronchioli and the lung tissue. These changes are represented by bronchial cell hyperplasia with hypermucigenesis, extrusion of bronchial cells, bronchiolar hypermucigenesis, parcellary squamous metaplasia or necrobiosis of epithelia, thickening of bronchial and bronchiolar walls by subepithelial cell accumulations, destruction of musculo-elastic structures with stenosis or ectasia; the vascular reactions are hyperhaemic and proliferative with an obstructive and fibrous tendency; the parenchymal lesions are atelectasias, intralobular emphysema, and cellular thickening of alveolar walls and interlobular areas. The acid phosphatase, Tween-60-esterase, naphthol-AS-D-acetate-esterase, proline-oxidase and hydroxyproline-2-epimerase activities are increasing, while the leucyl-aminopeptidase and beta-glucuronidase ones are decreasing. The qualitative observations are completed and sustained by quanitative studies of mucous cell kinetics, of cell accumulations and differentiations.

A series of sixty lung tumors operated during 1977 were histoenzymatically investigated (12 macrocellular carcionomas, 4 microcellular, 18 epidermoid, 18 cylindrocubic, 2 bronchiolo-alveolar cell carcinomas, 4 lung fibroblastic sarcomas, and 2 benign lung tumors: a haemangioma and a carcinoid tumor). There were tested 25 enzymes, hydrolases and oxidoreductases of different metabolic pathways. The histoenzymatic analysis of the neoplastic lung tissue compared with the normal adult human lung tissue pointed to a shifting of the metabolic balance, with the decrease of enzyme activities belonging to the Krebs tricarboxylic acid cycle and with the increase or maintenance of the level of enzymic activities belonging to the Embden-Meyerhoff-Parnas pathway and to the pentose shunt. The enzymes intervening in the protidic activity in all the malignant tumors of the lung. Some hydrolases were also more active lung tissue pointed out the existence of close relations between the normal epithelia and the cylindrocubic and bronchiolo-alveolar types, and of distant ones with the epidermoid and microcellular carcinomas which suffered more accentuated ecogenetic influences (stopping of differentiation/maturation, metaplasia) during the complex oncogenetic process.

The development of lung granulomas induced in rabbits by an intravenous injection of the complete Freund adjuvant containing dog pulmonary proteins was followed by histologic and histoenzymatic methods. By comparison with normal rabbit lungs. the developing structures of the induced lung granulomas showed an increase of all tested enzymes at 15 days, and a secondary intensity decrease of the activity of malic dehydrogenase, of acid and alkaline phosphatases, and of alanyl-aminopeptidase at 30 days. Only the hydroxyproline-epimerase showed at these intervals an increasing activity in the lung granulomas. The developed reticulinic fibrils appeared to have a highly intense alkaline phosphatase activity.

Well developed silicotic nodules of rabbit lungs were infected with tuberculosis and treated with tuberculostatics. The spatial evolution of lesions, as well as the density of intralesional and perilesional reticulinic fibrils were quantitatively analysed, measured by planimetric and target methods, and statistically analysed. Under tuberculostatics, the size of lesions, expressed in the dynamics of the SL/ST % ratio, rapidly diminished to half after three months. In the some period, the density of reticulinic fibrils expressed by the PA of the target method, increased, with significant differences between treated silicotuberculotic lesions and tuberculotic ones. The correlation analysis between these two divergent changes showed the interfering with other factors.

Human adult lung fragments removed from macroscopically undamaged and anthracosis exempted zones of lungs of 20 pneumonectomies made for cancer, were tested for 25 enzymic activities. The location and intensities of these enzymic activities were different in the lung tissue components; The bronchial epithelia contained highly active LDH, MDH, SDH, NADH-TR and NADPH-TR, glucose-6-phosphate dehydrogenase, active hydroxyproline-2-epimerase, alkaline phosphatase. Ca2+-activated ATP-ase, and beta-galactosidase. Bronchial and vascular muscles presented intense activities of LDH, MDH and SDH of alkalinephosphatase, AMP-ase and Ca2+-activated ATP-ase, as well as of beta-galactosidase. The alveolar walls presented high activities of SDH, MDH and LDH, of alkaline and acid phosphatases, of beta-galactosidase and of Tween-40 and 60-esterases, of HEP, cytochrome-oxidase and peroxidase. The free alveolar macrophages were active for LDH, MDH, SDH, NADH-TR and NADPH-TR, G1-6-ph-DH, acid and alkaline phosphatase, cytochrome-oxidase and peroxidase, HEP, AMP-ase and Mg2+-activated ATP-ase, Tween-esterases, naphthol-ASD-acetate esterase, and beta-galactosidase. The endothelia contained high activities of alkaline phosphatase, of AMP-ase and Mg2+-activated ATPase, of LDH, MDH and SDH, and of beta-galactosidase. In bronchial lymphoid nodules it was the LDH, MDH, SDH, cytochrome-oxidase and peroxidase, HEP, alkaline phosphatase and AMP-ase, Tween-60-esterase and beta-galactosidase that were active. The interlobular areas of the lung presented intense activities of SDH, MDH, LDH, HEP and cytochrome-oxidase. The activities of the other tested enzymes were weaker or absent in the adult human lung components, the same as those of aminopeptidases which were present only in some free alveolar macrophages. The discussion of some relationships between these enzymic actitivies and the morphology of the human adult lung tissue asserted that the latter could not be considered as a "normal" tissue but as one overstrained by the components of blood and polluted air.

A case of pulmonary blastoma in a 8-year-old girl is reported. The histopathologic analysis evidenced carcinomatous tubes with several cell layers developing into a mesenchymal cell mass with undifferentiated elements forming a dendroreticulated network with minimal endothelial, fibroblastic and collagenous differentiations. The initial tumoral formation within the lower left lobe was rapidly followed after resection by a local recidive and nine months later by a voluminous metastatic formation within the upper left lobe, radiologically treated. Discussion of the histopathologic characteristics of this case supports the hypothesis of a peculiar neoplastic entity of the lung, in which only the epithelial component of the lung was involved, while the mesenchymal mass presented an unaffected fetal structure.