Dielectric functions, chemical and atomic compositions of the near surface layers of implanted GaAs by In+ ions.

The surfaces of (100) GaAs were irradiated with In+ ions. The implanted samples were isobaric annealed at 800°C and then of dielectric function, the surface atomic concentrations of atoms and also the chemical composition of the near surface layers in these implanted semiconductor samples were obtained. The following investigation methods were used: spectroscopic ellipsometry (SE), Rutherford backscattering spectrometry analyses (RBSA) and X-ray photoelectron spectroscopy (XPS) in the study of the above mentioned quantities, respectively. The change of the shape spectra of the dielectric functions at about 3.0eV phonon energy, diffusion of In+ ions as well as chemical composition changes were observed after ion implantation and the thermal treatment. Due to displacement of Ga ions from GaAs by the In+ ions the new chemical compound InAs was formed. The relative amounts Ga2O3 and As2O3 ratio increase in the native oxide layers with the fluences increase after the thermal treatment of the samples. Additionally, it was noticed that the quantities of InO2 increase with the increasing values of the irradiated ions before thermal treatment.

Disseminated nocardiosis mimicking exacerbation of pulmonary sarcoidosis.

Nocardiosis is a rare, mixed suppurative and granulomatous, bacterial infection that can affect various organs, but most commonly lungs. Clinical manifestation is usually uncharacteristic; can mimic fungal, parasitic and mycobacterial infections or malignancy. Presentation can be also similar to that of the other granulomatous diseases, among them sarcoidosis. We present an unusual case of disseminated nocardiosis in a patient diagnosed before with sarcoidosis and treated with glucocorticoids. Clinical symptoms initially mimicked exacerbation of pulmonary sarcoidosis. The course of disease was severe.

Collagen receptors α(1)ß(1) and α(2)ß(1) integrins are involved in transmigration of peripheral blood eosinophils, but not mononuclear cells through human microvascular endothelial cells monolayer.

UNLABELLED: Asthma development may be driven by T helper lymphocytes with eosinophils playing the role of major effector cells. Recruitment of the inflammatory cells from blood to the airways is mediated by adhesive molecules, e.g. selectins and integrins. The most important in cell trafficking are integrins containing α(4) and ß(2) subunits. We hypothesized that also collagen receptors: α(1)ß(1) and α(2)ß(1), may be involved in cell migration to the inflammatory site in asthma. The aim of the study was to determine whether the inhibition of α(1)ß(1) or α(2)ß(1) integrins, affects transmigration of eosinophils and peripheral blood mononuclear cells (PBMC) through human microvascular endothelial cells monolayer (HMVEC) seeded on collagen IV coated wells in moderate persistent atopic asthmatics. METHODS: PBMC from 9 asthmatics were separated by gradient centrifugation followed by negative magnetic separation of eosinophils. Snake venom derived anti-adhesive proteins: viperistatin and VP12 (potent and selective inhibitors of α(1)ß(1) and α(2)ß(1) integrins, respectively) as well as VLO4 (a non-selective inhibitor of α(4)ß(1), α(5)ß(1) and α(v)ß(3) - used as a positive control), were used for inhibition studies. All anti-adhesive proteins studied, inhibited eosinophils, but only VLO4 affected PBMC transmigration through HMVEC. In bronchial asthma both collagen receptors α(1)ß(1) and α(2)ß(1) are likely to be involved in eosinophil transmigration to the inflammatory site. The role of α(2)ß(1) on lymphocytes is probably different. As the α(2)ß(1) integrin has been described as a stimulator of collagen accumulation, it might be, at least in part, responsible for asthma airway remodelling.

[Bilateral monitoring of cerebral oxygen saturation in aortic arch surgery]. / Bilaterales Monitoring der zerebralen Sauerstoffsättigung in der Aortenbogen-Chirurgie.

Cerebral ischemia with consecutive neurological damage is a typical complication in aortic arch surgery. Therefore, intraoperative neuromonitoring is of increasing interest. This paper describes the role of bilateral near-infrared-spectroscopy (NIRS) in detecting cerebral ischemia. In the case of a patient with acute aortic dissection (Daily, type A), an unexpected sudden reduction of perfusion of the right carotid artery could easily be detected with the help of two instruments INVOS 3100A. The decrease in the saturation values from 74% to 54% correlated well with the drop of blood pressure in the right radial artery. Clamping of the aorta with interruption of the blood flow into the innominate artery through the false lumen was the reason for the low cerebral perfusion. After repositioning the aortic clamp NIRS in combination with invasive blood pressure monitoring sufficiently allowed to control the further course of cerebral perfusion. The NIRS is a non-invasive, easy to handle, and easy to interpret method for intraoperative monitoring of the neurological status. Therefore in our opinion it has got some relevant advantages in contrast to other neuromonitoring methods in aortic arch surgery.

A literary approach to teaching cultural competence.

Cultural competence is a necessity in today's diverse society and an essential component of clinical practice. As an adjunct to other sources, literature can enrich teaching and sensitize students to cultural issues in health care. The Spirit Catches You and You Fall Down is a beautifully written and compelling story well suited for instructional purposes. Although widely recommended, nurses are largely ignored in this story of a Hmong family seeking medical care. The book describes how the health care system failed to provide adequate care to patients from a different cultural background despite providers' good intentions. Nurse educators can use structured discussion guides to synthesize literary accounts such as The Spirit Catches You and You Fall Down with theory and research about cultural competence.

Involvement of the essential yeast DNA polymerases in induced gene conversion.

In the yeast Saccharomyces cerevisiae three different DNA polymerases alpha, delta and epsilon are involved in DNA replication. DNA polymerase alpha is responsible for initiation of DNA synthesis and polymerases delta and epsilon are required for elongation of DNA strand during replication. DNA polymerases delta and epsilon are also involved in DNA repair. In this work we studied the role of these three DNA polymerases in the process of recombinational synthesis. Using thermo-sensitive heteroallelic mutants in genes encoding DNA polymerases we studied their role in the process of induced gene conversion. Mutant strains were treated with mutagens, incubated under permissive or restrictive conditions and the numbers of convertants obtained were compared. A very high difference in the number of convertants between restrictive and permissive conditions was observed for polymerases alpha and delta, which suggests that these two polymerases play an important role in DNA synthesis during mitotic gene conversion. Marginal dependence of gene conversion on the activity of polymerase epsilon indicates that this DNA polymerase may be involved in this process but rather as an auxiliary enzyme.

Off-bypass coronary bypass grafting via minithoracotomy using mechanical epicardial stabilization.

BACKGROUND: Minimally or less invasive surgical coronary revascularization has gained increasing interest along with new techniques and devices designed for easier and safer procedures. Until recently, it appeared questionable whether grafting techniques with avoidance of cardiopulmonary bypass techniques would allow adequate results compared with conventional techniques using cardioplegic arrest. METHODS: Since June 1996, minimally invasive direct coronary artery bypass grafting procedures without cardiopulmonary bypass were intended in 24 patients (19 male, 5 female; age, 60.5 +/- 10.5 years) applying a special system (CardioThoracic Systems, Inc) for internal mammary artery access and epicardial surface stabilization approaching through an anterolateral minithoracotomy. Neither video-assisted preparation nor additional pharmacologic stabilization was applied. Concomitant risk factors and associated comorbidity were frequent. RESULTS: The procedure was completed in 23 patients, grafting the left anterior descending coronary artery (n = 21) or diagonal branches (n = 3, 1 sequential) as scheduled. In 1 case with internal mammary artery dissection, cardiopulmonary bypass and sternotomy became necessary. Simultaneous carotid endarterectomy was performed in 1 patient. There were two episodes of intraoperative ventricular fibrillation; no other major complications occurred. Postoperative evaluation was obtained in 16 patients (15 by angiography, 1 by Doppler echocardiography) so far and revealed adequate graft function and patency. CONCLUSIONS: Using specially designed instruments for internal mammary artery access and epicardial surface stabilization, minimally invasive direct coronary artery bypass grafting procedures via a minithoracotomy avoiding cardiopulmonary bypass techniques may be applied safely and successfully, even in increased risk constellations.

Release of human monocytes protein C and the cofactor protein S in vitro.

Monocytes may contribute to a coagulation process by expression of the tissue factor and by synthesizing factors V, VII, X and XIII. Cultured blood monocytes also express both the tissue plasminogen activator and the plasminogen activator inhibitor I. The present study assesses the ability of human monocytes to secrete protein C and its cofactor protein S, which are potent inhibitors of the clotting cascade. Monocytes derived from the blood of healthy volunteers and prepared according to Boyum were cultured for up to 36 hours with or without lipopolisaccharide from Escherichia coli. After different times of incubation, the concentrations of proteins C and S in the supernatants were measured in order to determine synthesis of proteins, monocytes were cultured in the presence or absence of cycloheximide, the protein synthesis inhibitor. The concentration of protein C was estimated by means of the ELISA Protein C test (Boehringer Mannheim). Protein S concentrations were measured by rocket immunoelectrophoresis according to Laurell, using monospecific antisera (American Diagnostica Inc., N.Y.). The study showed that human monocytes, when stimulated by lipopolisaccharide, release proteins C and S in vitro. The concentration of these proteins in the culture supernatants markedly increased with time during the 36-hour observation. The supernatants obtained from the culture of unstimulated monocytes did not contain detectable quantities of the investigated proteins. The exposure of the cells to cycloheximide did not suppress the release of proteins C and S. In conclusion, our results suggest that monocytes are not able to synthesize proteins C and S. They can only release these factors. Furthermore, monocytes may be responsible for coagulation due to the inactivation of factors Va and VIIIa by protein C.

DNA polymerase III is required for DNA repair in Saccharomyces cerevisiae.

We have studied the role of DNA polymerase III, encoded in S. cerevisiae by the CDC2 gene, in the repair of yeast nuclear DNA. It was found that the repair of MMS-induced single-strand breaks is defective in the DNA polymerase III temperature-sensitive mutant cdc2-1 at the restrictive temperature (37 degrees C), but is not affected at the permissive temperature (23 degrees C). Under conditions where only a small number of lesions was introduced into DNA (80% survival), the repair of MMS-induced damage could also be observed in the mutant at the restrictive temperature, although with low efficiency. When the quantity of lesions increased (50% survival or less), the repair of single-strand breaks was blocked. At the same time we observed a high rate of reversion in the meth, his and trp loci of the cdc2-1 mutant under restrictive conditions. The results presented suggest that DNA polymerase III is involved in the repair of MMS-induced lesions in yeast DNA and that the cdc2-1 mutation affects the proofreading activity of this polymerase.

Chemical mutagenesis and DNA synthesis in cdc8, a DNA replication mutant of Saccharomyces cerevisiae.

Incubation of cdc8 mutants of the yeast Saccharomyces cerevisiae in YPD under permissive conditions, when DNA replication is taking place, prior to transfer to restrictive conditions, strongly stimulates induction of cdc+ colonies of ethyl methane sulphonate (EMS)- and methyl methane sulphonate (MMS)-treated yeast strains HB23 (cdc8-1/cdc8-3), HB26 (cdc8-3/cdc8-3) and HB7 (cdc8-1/cdc8-1). After diepoxybutane (DEB) treatment, both the induction of cdc+ colonies and their stimulation after incubation in YPD under permissive conditions is low. The results obtained show that stimulation of induction of cdc+ colonies under permissive conditions occurs not only after UV-treatment, but also after treatment with such mutagens as EMS and MMS.

The CDC8 gene product is required for transformation with episomal and integrative plasmids in Saccharomyces cerevisiae.

The product of the yeast CDC8 gene (thymidylate kinase), which is required for chromosomal, mitochondrial and 2 mu plasmid replication, also participates in plasmid transformation processes in S. cerevisiae. The thermosensitive cdc8-1 mutant strain was transformed with episomal pDQ9 and integrative pDQ9-1 plasmids both of which carry the CDC8 gene. The results suggest that thymidylate kinase is essential for the expression of genes carried on transforming episomal plasmid DNA (probably through its replication) and is also essential for homologous recombination between chromosomal and linearized integrative plasmid DNA.

Audit in histopathology: description of an internal quality assessment scheme with analysis of preliminary results.

In the first six months of a formal Internal Quality Assessment Scheme operating in the Department of Histopathology, Broadgreen Hospital, Liverpool, 1005 items of data were gathered, relating to 80 cases. The scheme entails a random 2% sample of biopsy specimens being selected, each case being analysed using a structured proforma, and a numerical scoring system being allocated to all aspects of specimen handling. Technical and secretarial performance was good while the quality of clinical information provided by the requesting clinician was poor. There was a wide variation in reporting times, which related partly to the complexity of the specimen, and partly to the degree of supervision required by the reporting pathologist. Month by month analysis of reporting times showed a significant increase in reporting times associated with rotation of junior staff, but not with periods of annual leave. Pathologist performance scores were good, but close examination of components of the overall score for an individual pathologist indicated occasional areas of weakness (such as the adequacy of the macroscopic report). It is concluded that this scheme is worthwhile and its practice will be continued indefinitely. The comprehensive nature of the analysis allows for the formal identification of areas of work which need improvement, and the allocation of a formal numerical score allows improvement in these areas to be monitored. The monthly meetings provide a means whereby performance scores are fed back to the participating pathologists, and they are also of general educational value regarding histological reporting practice. It is intended that the scheme be extended to include the assessment of special stains, frozen sections, and adequacy of the report delivery service. The system is easily adaptable for use within other histopathology departments.

Decreased chemical mutagenesis in cdc8, a DNA replication mutant of Saccharomyces cerevisiae.

In the DNA replication mutant of yeast cdc8 the frequency of chemically induced reversion of lys2-1 and hom2-1 was found to be reduced. Mutation induced by ethyl methanesulfonate (EMS) were greatly diminished in the strain homozygous for the cdc8-1 gene.

Role of the CDC8 gene in the repair of single strand breaks in DNA of the yeast Saccharomyces cerevisiae.

It has been found that the repair of single strand breaks is defective in the DNA replication mutants cdc8-1 and cdc8-3 of Saccharomyces cerevisiae both in permissive (23 degrees C) and restrictive conditions (36 degrees C). In permissive conditions we observed a significant delay in single strand break repair in a diploid strain HB7 (cdc8-1/cdc8-1), as compared with the wild-type strain. Under restrictive conditions no repair was observed, but rather degradation of MMS-damaged DNA occurred. It has been also found that the repair of single strand breaks in yeast is inhibited by cycloheximide but not by hydroxyurea.

[Factors influencing prophylaxis of caries and teeth treatment in children with mild mental retardation]. / Cynniki wplywajace na profilaktyke i leczenie zebów u dzieci upósledzonych umyslowo w stopniu lekkim.

The analysis indicated factors affecting caries prophylaxis and teeth treatment in children with mild mental retardation. The factors were sought in the personality of the child, its family environment and the work of the dentist. A significant effect on the cooperation of the dentist with the patient was exerted by such factors as the level of anxiety before dental procedure, motivation to treatment, intensity of teaching of oral hygiene, life period when teaching was started, frequency of teethbrushing, regular contacts with the dentist, and the mode of child reception by the dentist.

The effect of DNA replication on mutation of the Saccharomyces cerevisiae CDC8 gene.

Incubation in YPD medium under permissive conditions when DNA replication is going on, strongly stimulates the induction of cdc+ colonies of UV-irradiated cells of yeast strains HB23 (cdc8-1/cdc8-3), HB26 (cdc8-3/cdc8-3) and HB7 (cdc8-1/cdc8-1). Inhibition of DNA replication by hydroxyurea, araCMP, cycloheximide or caffeine or else by incubation in phosphate buffer pH 7.0, abolishes this stimulation. Thus the replication of DNA is strongly correlated with the high induction of cdc+ colonies by UV irradiation. It is postulated that these UV-induced cdc+ colonies arise as the result infidelity in DNA replication.

Rapid reporting on fine needle aspiration of breast lumps in outpatients.

A retrospective analysis of the performance and value of fine needle aspiration of symptomatic breast masses in a special outpatient "breast clinic" within a district general hospital was carried out. All but a few aspirations were performed by a group of histopathologists, with, immediate cytological reporting. Fine needle aspiration was more sensitive for detecting malignancy than clinical assessment alone, the sensitivity increasing with the experience of the aspirator. The results compared favourably with those in reported series from specialist centres in the United Kingdom. The value of fine needle aspiration extends to the overall management of patients with breast masses but the results must be assessed in conjunction with the clinical context in view of the possibility of false negative or, more rarely, false positive cytological diagnoses.

Locally invasive pulmonary aspergillosis occurring in a gardener: an occupational hazard?

Fatal locally invasive pulmonary aspergillosis occurred in a previously fit young patient who had no predisposing factors other than exposure to fungal spores in his occupation as a gardener.

Epidural adhesions after chymopapain chemonucleolysis.

Epidural adhesions were discovered in seven of nine patients undergoing surgery for failed chymopapain chemonucleolysis. Clinically the adhesions were very vascular, prolific and adherent to the nerve root, dura and the porieties. The histological composition was similar to the normal tissues of the epidural space from the post-mortem controls and also to adhesions discovered at surgery in a non-injected patient, except that there was an increase in fibrous tissue, which was poorly cellular. There was no evidence of an inflammatory infiltrate. Such adhesions may partly explain the failure of chemonucleolysis and prejudice the success of surgery by potentiating further adhesion formation.