The psbA-gene from a red alga resembles those from Cyanobacteria and Cyanelles

Summary Plastid DNA (ptDNA) from the unicellular red alga Cyanidium caldarium was isolated. A 5.8 kb Eco RI, fragment containing the entire psbA-gene was cloned and the nucleotide sequence of the psbA-gene determined. At the carboxyl terminus the encoded protein (D1) contains the seven amino acid-insertion which was found to be typical of the cyanobacteria and the cyanelles of Cyanophora paradoxa. However, the overall sequence homology does not support a direct relationship between the plastids of Cyanidium, cyanelles and the cyanobacteria. As in other photosynthetic organisms the psbA-gene is transcribed as a monocistronic mRNA. The ribosomal RNA operon was located 4 kb upstream of the psbA-gene.     

Primary Immunodeficiency Diseases in Latin America: First Report from Eight Countries Participating in the LAGID

The Latin American Group for Primary Immunodeficiencies, formed in 1993, presently includes 12 countries. One goal was to study the frequency of primary immunodeficiencies in various regions of the American continent and to enhance knowledge about these diseases among primary-care physicians, as well as allergist–immunologists. Important for this purpose was the development of a registry of primary immunodeficiencies using a uniform questionnaire and computerized database. To date, eight countries have collected information on a total of 1428 patients. Predominantly antibody deficiencies were reported in 58% of patients, followed by cellular and antibody immunodeficiencies associated with other abnormalities in 18%, immunodeficiency syndromes associated with granulocyte dysfunction in 8%, phagocytic disorders in 9%, combined cellular and antibody immunodeficiencies in 5%, and complement deficiencies in 2% of patients. The information gathered from this initial analysis of data will serve to expand the patient database to more areas within participating countries and to new countries and to increase collaboration toward better diagnosis and treatment of these diseases.     

Investigations on neurotoxicity of chemical substances at the workplace

Summary A cross-sectional study was performed in order to investigate the influence of chronic lead-exposure on the peripheral nervous system. We examined 148 male workers of a storage battery manufacturing plant, who had been exposed to lead metal and inorganic lead compounds for 1 to 28 years (mean 11 years). Fifteen workers with non-occupational risks of peripheral neuropathy (former diseases, alcohol abuse, medication) were excluded from the study. The investigation program comprised: case history, physical examination, analyses of blood- and urine-samples and determination of maximal motor, mixed and sensory conduction velocity (NCV) of the ulnar and median nerve of the right forearm. Objectively no worker showed any signs of health effects related to lead exposure. The Biological Monitoring included the determination of (1) Blood-lead level (Pb-B), (2) Free erythrocyte porphyrins (FEP), (3) -Aminolevulinic acid dehydratase (ALA-D) and (4) -Aminolevulinic acid in urine (ALA-U). Further time-weighted-average (TWA)-values of Pb-B were calculated on the basis of several determinations over the period 1975–1981. The following actual (TWA) median values resulted: Pb-B 53 g/dl (54 g/dl), ALA-U 5.6 mg/l (8.4 mg/l), FEP 2.0 mg/l (2.0 mg/l). The Biologischer Arbeitsstoff Toleranz Wert (BAT) of 70 g//dl for Pb-B was exceeded in 15 workers (11%), and of 15 mg/l for ALA-U in 30 cases (23%). In comparison with age-matched controls, the lead workers showed a mild slowing of NCV with mean values between 0.8 and 2.0 m/s. Multiple stepwise regression analyses revealed statistically significant correlations between the four NCV and age as well as Pb-B. There were better correlations by using TWA than actual data of Pb-B. Consideration of the results of the regression analyses, together with an evaluation of the individual neurophysiological status as a function of internal lead exposure, a dose-effect-relationship was found only in the case of Pb-B exceeding 70 g/dl. From our study it is concluded that chronic lead exposure resulting in blood-lead levels of below 70 g/dl is no occupational risk causing a functionally significant slowing of nerve conduction velocities.With Grants from the Deutsche Forschungsgemeinschaft, Bonn (Project no. Va 23/19-1)     

Clinical features and outcome of maintenance hemodialysis patients with COVID-19 from a tertiary nephrology care center in Romania

Background There is limited information about the clinical characteristics, treatment and outcome of maintenance hemodialysis patients with COVID-19. Moreover, regional differences are also conceivable since the extend and severity of outbreaks varied among countries.Methods In this retrospective, observational, single-center study, we analyzed the clinical course and outcomes of 37 maintenance hemodialysis patients (median age 64 years, 51% men) hospitalized with COVID-19 from 24 March to 22 May 2020 as confirmed by real-time PCR.Results The most common symptoms at admission were fatigue (51%), fever (43%), dyspnea (38%) and cough (35%). There were 59% mild/moderate patients and 41% severe/critical patients. Patients in the severe/critical group had a significantly higher atherosclerotic burden since diabetic kidney disease and vascular nephropathies were the most common primary kidney diseases and eighty percent of them had coronary heart disease. Also, Charlson comorbidity score was higher in this group. At admission chest X-ray, 46% had ground-glass abnormalities. Overall, 60% patients received hydroxychloroquine, 22% lopinavir–ritonavir, 11% tocilizumab, 24% systemic glucocorticoids, and 54% received prophylactic anticoagulation. Seven (19%) patients died during hospitalization and 30 were discharged. The main causes of death were cardiovascular (5 patients) and respiratory distress syndrome (2 patients). In Cox regression analysis, lower oxygen saturation, anemia and hypoalbuminemia at admission were associated with increased mortality.Conclusions In conclusion, we observed a high mortality rate among maintenance hemodialysis patients hospitalized for COVID-19. Anemia, lower serum albumin and lower basal oxygen saturation at admission were factors associated with poor prognosis.     

Die analyse von aluminium im serum und urin zur überwachung emonierter personen

Zusammenfassung Die Einführnung der flammenlosen Atomabsorptionsspektrometrie in die chemische Analytik ermöglicht eine einfache quantitative Bestimmung des Aluminiums im biologischen Material. Die verwendeten Analysen-methoden und deren Zuverlässigkeitskriterien wurden beschrieben. Entsprechend der heute üblichen Verfahren zur Überwachung schwermetallexponierter Personen wurden von uns bei verschiedenen Kollektiven Aluminiumbestimmungen im Blut und Urin durchgeführt. Untersucht wurde ein Kollektiv von 110 Arbeitern eines Korund-herstellenden und -verarbeitenden Werkes. 82 dieser Arbeiter waren durch staubförmigen Korund exponiert, während 28 Personen an den Öfen zusätzlich noch Metalldämpfen ausgesetzt waxen. Die Expositionsdauer betrug im Mittel 6,9 Jahre. Als Vergleichskollektiv dienten 40 männliche nicht aluminiumexponierte Probanden. Zusädtzlich wurden 33 Dialyse-Patienten, die mit Aluminiumhydroxid (Aludrox) therapiert wurden, in die Studie einbezogen.Für die Aluminiumausscheidung im Urin errechnete sich bei den Normalpersonen eine obere Normgrenze von 30 g/l. Die Ausscheidungswerte der aluminiumexponierten Personen lagen mit einem Median von 39 g Al/l signifikant höher als das Normalkollektiv. Erwartungsgemä zeigten die dampfförmig belasteten Personen einen statistisch signifikant höheren Al-Spiegel im Urin als die staubförmig belastete Gruppe.Die Serumanalysen ergaben keine Hinweise für einen signifikanten Unterschied gegenüber Normalpersonen. Aus den Untersuchungen der Seren von nicht aluminiumexponierten Probanden errechnete sich ein oberer Grenzwert von 35 g/l. Der Serum-Aluminium-Spiegel der exponierten Personen war von der Art und Dauer der Exposition nicht beeinflut. Dagegen lagen die Aluminium-Spiegel im Serum der Dialyse-Patienten im Bereich von 6 – 254 g/l. Bei dieser Patientengruppe mit erhöhten Serum-Aluminiumwerten wurden keine klinischen Zeichen einer manifesten Toxicität gefunden. Damit kommt den Aluminiumkonzentrationen im biologischen Material der aluminiumexponierten Arbeiter keine gesundheitsgefahrdende Relevanz zu.Bei der inhalativen Aufnahme von Aluminium scheint die Menge des resorbierten und in die Blutbahn übergehenden Aluminiums gering zu sein. Hinweise für eine Akkumulation des Metalls im Organismus wurde bei Versuchen mit D-Penicillamin nicht gefunden.Aluminiumbestimmungen im Serum oder Harn sind für die Überwachung von Korund-herstellenden und -verarbeitenden Personen nach diesen Ergebnissen nicht notwendig. Bei Substanzen, wie dem Aluminium, mit geringer Resorptions-quote und groer Toleranzbreite für den menschlichen Organismus sowie ohne manifeste signifikante Gesundheitsschäden erscheint ein Biological Monitoring nicht indiziert.D 29     

La protonterapia: indicaciones y perspectivas

Protons have considerable targeting advantages in the conduct of precise conformational radiotherapy, enabling dose escalation and a better protection of critical organs. Protons differs from photons and electrons used in classical radiotherapy due to their specific physical characteristics, Bragg peak and narrow lateral penumbra. Currently, treatment of ocular melanoma, chordoma and chondrosarcoma of the base of skull and paediatric tumours are widely accepted. Others clinical indications are still being evaluated (meningioma, etc.). Generalised isocentric application and proton intensity modulation can increase the clinical indications for its use. It is a technique which, despite its current expansion, appears “restricted” because of the scarcity of equipments due to its high cost.     

Donor treatment with mycophenolate mofetil: protection against ischemia-reperfusion injury in the rat

BACKGROUND: Mycophenolic acid, the active metabolite of mycophenolate mofetil, inhibits the glycosylation of cell membrane glycoproteins. We hypothesized that impaired glycosylation of cell adhesion molecules on endothelial cells in vivo results in decreased susceptibility to inflammation or immunogenicity after allogeneic transplantation. METHODS: The expression of mannose residues on cultured rat endothelial cells was examined after stimulation with interleukin 1 in the presence or absence of mycophenolic acid using labeled Galanthus nivalis agglutinin. The in vitro adhesion of blood leukocytes to heart tissue was examined using peripheral blood leukocytes of recipient origin and sections of donor heart tissue exposed to ischemia-reperfusion injury after pretreatment with vehicle or mycophenolic mofetil. (LEWxBN)F1 donor rats were treated with 20 or 60 mg/kg/day of mycophenolate mofetil for 1 or 2 weeks followed by transplantation of the heart into Lewis recipients after storage in heparin-containing normal saline for either 10 min at 4 degrees C or 120 min at room temperature. RESULTS: Endothelial cells stimulated in vitro with interleukin 1 showed an increase in a population of strongly mannose-positive cells, which was prevented by the addition of mycophenolic acid during the culture. The in vitro adhesion of peripheral blood leukocytes to cardiac tissue sections exposed to prolonged storage and reperfusion was significantly less if the donor had been treated with mycophenolate mofetil. Treatment of cardiac graft donors with mycophenolate mofetil protected the graft against early graft failure after prolonged storage at room temperature, because the mean graft survival was 9.4+/-0.6 days for grafts that came from donors treated with mycophenolate mofetil versus 1.2+/-0.9 days (P<0.05) for grafts that came from vehicle-treated donors. Donor pretreatment with mycophenolate mofetil did not affect the survival time of heart grafts transplanted after 15 min of standard cold storage or the survival of grafts transplanted into presensitized recipients. CONCLUSION: Donor treatment with mycophenolate mofetil protects cardiac grafts against primary nonfunction after prolonged tepid storage, which may be related to the inhibition of glycosylation of cell adhesion molecules involved in ischemia-reperfusion injury.