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This comparative study investigates the relationship between sarcoplasmic reticulum (SR) calcium (Ca2+) ATPase transport activity and phospholamban (PLB) phosphorylation in whole cardiac homogenates around birth and during postnatal development until weaning. At fetal day 20, the rate of homogenate oxalate-supported Ca2+ uptake was 23% of that at postnatal day 6 (0.34 ± 0.08 vs 1.46 ± 0.37 nmoles Ca2+/mg wet ventricular weight/min, respectively; P < 0.05). This was accompanied by a 2-fold gain in heart mass. Between postnatal days 6 and 21, there occurred a further 4-fold increase in heart mass which was accompanied by only a 1.3-fold increase in SR Ca2+ transport activity. Levels of phosphorylated PLB formed in vitro in the presence of radiolabelled ATP and catalytic subunit of protein kinase A increased approx. 4-fold between fetal day 20 and postnatal day 21. In this early developmental period, SR Ca2+-transport values were linearly related to the respective 32P-PLB levels suggesting coordinated developmental changes of SR Ca2+ ATPase and PLB. Developmental changes in SR Ca2+ transport and 32P-PLB levels were thyroid hormone(TH)-dependent as revealed from analysis of these parameters in 21-day-old rats with experimentally induced eu-, hypo- and hyperthyroid states. It appears that TH-dependent changes in the phosphorylation of PLB play a major role for the increase in SR Ca2+ transport activity between birth and weaning.

Objective: To investigate whether the adenosine-antagonist theophylline reduces the incidence of contrast-induced nephropathy (CIN). Design and setting: Prospective, comparison to series of patients at similar risk of CIN in a university hospital medical ICU. Patients: 78 ICU patients with at least one risk factor for CIN undergoing 150 consecutive contrast examinations. Interventions: Administration of 200 mg theophylline/70 kg BW intravenously 30 min before that of 100 ml or more low-osmolarity contrast medium (CM). Measurements and results: Concentrations of serum creatinine and blood urea nitrogen (BUN), urine volume, fluid balance, and the incidence of CIN [increase in creatinine ≥0.5 mg/dl (=44.2 µmol/l) within 48 h] were monitored for 48 h. Despite the large number of risk factors (6.8 per patient) including a high dose of CM (169.4 ml), impaired renal function (51%), diabetes (38%), aminoglycosides (61%), vancomycin (53%), catecholamines (52%), creatinine concentrations were not increased 24 h (1.40±0.92 mg/dl) or 48 h (1.38±0.88 mg/dl) after CM [1.47±1.0 mg/dl (=130±88 µmol/l)] vs. baseline. The fluid balance was not different before (+3 ml/h) and after CM (–9 ml/h). The urine volume slightly increased after CM and theophylline (184 ml/h vs. 164 ml/h). Only three patients (2%) developed CIN. The incidence was significantly lower than that of 14% (78/565) in the control series with patients at comparable risk of CIN (p

A 65-year-old woman underwent resection of a distal common bile duct carcinoma (Whipple’s procedure). Twelve months later a single hepatic metastasis was detected and a chemoembolization was performed. Immediately after chemoembolization the patient developed a multimicrobial sepsis including Clostridium perfringens. CT scans depicted pathognomonic signs of gas-containing abscess in the necrotic liver metastasis. She was subsequently treated with broad-spectrum antibiotics, abscess drainage and hyperbaric oxygen therapy. We conclude that antibiotic prophylaxis is recommendable for chemoembolization of liver metastasis in patients with risk factors like intestinal biliary reflux (bilioenteric anastomosis or papillotomy and biliary stenting) and bile duct cancer, otherwise severe sepsis including clostridium bacteremia may occur.

La triade de foi, esperance et amour dans I Corinthiens 13,13 se trouve dans un autre ordre dans I Thessaloniciens. L'A. analyse la triade dans I Th 1,3 et 5,8, l'utilisation des trois termes dans l'epitre, l'origine de la triade et la comprehension et interpretation chez Paul et dans I Co 13,13

The effect of mild trypsination on the system-II reaction pattern of inside-out thylakoids has been analyzed by measurements of oxygen yield, fluorescence induction and laser-pulse-induced absorption changes at 320 and 830 nm. The following was found. (1) The average oxygen yield per flash drastically declines after trypsination at pH 7.4, while at pH 6.5 only small effects are observed. (2) The area over the fluorescence induction curves becomes reduced by 30–40% after trypsination at either pH 6.5 or 7.4, but in the latter case the maximum level is attained only after addition of hydroxylamine as PS-II donor. On the other hand, the area over the induction curve in the presence of DCMU, which is 10–12 times smaller than without DCMU, remains unaffected by trypsin treatment. (3) The oscillation pattern of the oxygen yield induced by a flash train in dark-adapted inside-out thylakoids is not markedly affected by trypsin treatment, even at more than 80% inhibition of the oxygen-evolving capacity. (4) After trypsination of inside-out thylakoids, a large 10 μs decay arises in the relaxation kinetics of the 830 nm absorption changes, whereas the 320 nm absorption changes are dominated by a rather slow decay. (5) The half-life time of the microsecond kinetics at 830 nm elicited by trypsination of inside-out thylakoids reveals almost the same pH dependence as the corresponding relaxation kinetics in Tris-washed inside-out thylakoids. (6) The relaxation kinetics of the absorption changes at 320 and 830 nm in Tris-washed inside-out thylakoids become significantly modified after trypsin treatment. Based upon these findings, it is concluded that beyond the well-characterized polypeptides with 16, 23 and 33 kDa there exists a further protein that is exposed to the inner side of the thylakoid and that affects the electron transport in system II. The nature and the physiological role of this polypeptide still remain to be elucidated.

14C measurements on continuous weekly samples of atmospheric CO2 and hydrocarbons, collected in a rather densely populated area are presented. The deviation of the measured 14C data from the clean air level is primarily due to CO2 from the combustion of fossil fuels. This is confirmed by fossil fuel admixture estimates individually calculated with an atmospheric dispersion model. Up to 10 percent admixture is predicted by this model and observed from the 14C shift for weekly averages, particularly during the winter season. Natural CO2 admixture due to soil respiration, however, even in winter, is of the same order of magnitude, but much larger in the warm season: the considerable variations in CO2 concentration in summer are almost exclusively controlled by natural sources. Using tree leaf samples, we have been able to identify boiling water reactors (BWR) as weak sources of 14CO2. Atmospheric samples taken in the environment of the pressurized water reactors (PWR) Biblis show that the 14C release of these reactors is primarily in the form of hydrocarbon 14C. The source strength of the various power plants, calculated on the basis of our observations in their environment, ranges from 0.5 to 7Ci per year.

The category of merotopic spaces and uniformly continuous functions is shown to be adjoint to a category of completely distributive lattices with distinguished bases and grills and complete homomorphisms preserving these structure-sets. Suitable (co-)restrictions yield a lattice-theoretical representation of nearness spaces.

Es wird uber die Darstellung der explosiven 1:1-Addukte (CH3)2NCl · SbCl3 (II) und (CH3)2NCl · SbCl5 (III) aus (CH3)2NCl (I) und den entsprechenden Lewis-Sauren berichtet. Die Schwingungsspektren von I—III werden zugeordnet und diskutiert. Chlorodimethylamine and the Addition Compounds with Antimony Chlorides (CH3)2NCl (I) reacts with antimony chlorides to yield the explosive 1:1-addition compounds (CH3)2NCl · SbCl3 (II) and (CH3)2NCl · SbCl5 (III). The vibrational spectra of I—III are assigned and discussed.

Das lipophile Antibioticum Rifampicin wird erfolgreich gegen Tuberkulose eingesetzt. Auf molekularer Ebene stort es den Stoffwechsel von Eubakterien durch die Blockierung der RNA-Synthese. Dieser Effekt ist die Folge der starken Bindung des Arzneimittels an eine einzige und hochspezifische Bindungsstelle auf der DNA-abhangigen RNA-Polymerase. Die Katalyse des Kettenstarts der RNA-Synthese und die der Kettenverlangerung werden durch das Enzym-gebundene Arzneimittel stark gehemmt. Diesen Befund kann man durch den Einflus des Enzym-gebundenen Rifampicins auf die Bindungsstellen fur die Reaktionsprodukte Diphosphat und RNA erklaren. Um seinen Angriffspunkt zu erreichen, mus das Antibioticum in das Cytoplasma der Bakterien eindringen. Es wurden Mutanten entdeckt, die resistent gegen Rifampicin sind, weil sie es nur in Spuren aus dem Medium aufnehmen konnen. Das Gen, das diesen Effekt bewirkt, wurde kloniert. Es verleiht Bakterienzellen mit hochempfindlicher RNA-Polymerase eine bemerkenswerte Resistenz gegen das Antibioticum.

Washing inside-out spinach thylakoids with 250 mM NaCl at pH 7.4 causes up to 75% inhibition of oxygen evolution which has been shown by reconstitution experiments to be due mainly to the removal of a 23 kDa protein (Akerlund, H.E., Jansson, C. and Andersson, B. (1982) Biochim. Biophys. Acta 681, 1–10). Here we have found the same degree of inhibition and reconstitution of oxygen evolution measured either in flash light or in continuous light at different light intensities, which suggests that the salt-washing causes a complete block of electron transport in certain chains rather than a decreased rate in all chains. Flash-induced absorbance changes at 320 nm, reflecting mainly the electron transfer at the Photosystem-II acceptor side, from the primary to the secondary plastoquinone in their semiquinone form (PQ−APQ−B → PQAPQ2−B) and to minor extent the donor side of Photosystem II (Renger, G. and Weiss, W. (1983) Biochim. Biophys. Acta 722, 1–11), were measured under repetitive excitation conditions. Salt-washing the inside-out thylakoids caused a change in decay rate from 500–600 μs down to 200 μs, interpreted as an increased proportion of recombination between PQ−A and chlorophyll-a+II. Addition of the 23 kDa protein restored the kinetics up to some 400 μs. Measurements made on dark-adapted material gave evidence that salt-washing also affected S-state turnover. We conclude that the 23 kDa protein functions on the water-splitting side of Photosystem II and is indispensible for the photosynthetic water oxidation.

The lipophilic antibiotic rifampicin is successfully used in the treatment of tuberculosis. On the molecular level it interferes with the metabolism of Eubacteria by blocking RNA synthesis. This effect is the consequence of the tight binding of the drug to a single and highly specific binding site on the DNA-dependent RNA polymerase. The enzyme-bound drug strongly inhibits RNA chain initiation and chain elongation. This inhibition can be explained by the influence of enzyme-bound rifampicin on binding sites for the reaction products diphosphate and RNA. In order to reach its target the antibiotic must penetrate into the cytoplasm of the bacteria. Mutants have been discovered which are resistant to rifampicin because its uptake from the medium is significantly reduced. The gene responsible for this effect has been cloned. It confers on bacterial cells with highly sensitive RNA polymerases a remarkable resistance to the drug.

The energy resolution and thermal performance of a high purity Ge-detector system cooled by a cryogenic refrigerator is described. The mechanical vibrations of the cryomachine are damped effectively leading to a degradation in energy resolution of 200 eV only. Cool-down time is two hours and output pulse height stability is excellent between 82 and 94 K. For data display and spectrum analysis an economic personal computer-based system is used.

Eine interessante Ausgangslage: der Oberbefehlshaber der Schweizer Armee, General Herzog, schrieb in seinem Schlusrapport uber die Grenzbesetzung anlaslich des Deutsch-Franzosischen Krieges 1870/71: «Die Marschtuchtigkeit des Schweizer Soldaten last bedenklich zu wunschen ubrig.»

Photosynthetic water cleavage is the “heart” of the biological solution of solar energy exploitation of the biosphere. The process takes place within the thylakoid membrane and is supported by two photosystems which are connected by a plastoquinone pool (for recent review see ref. 1). The light-induced reaction sequence in system II leads to water cleavage into molecular oxygen and hydrogen bound to plastoquinone which is of moderate reducing power. In system I the electronic energy of metabolically bound hydrogen is further enhanced through the light-driven transfer to NADP+. Free energy is additionally stored as a transmembrane electrochemical potential gradient which is used for ATP synthesis. This organizational scheme indicates that the essential steps for water cleavage are realized by system II.

Publisher Summary This chapter presents the studies on the mechanism of photosynthetic oxygen formation. Photosynthetic water cleavage by visible light is the cornerstone of the evolutionary development of solar radiation exploitation as unique free energy source of biological organisms. It is energetically driven by two light reactions that are connected via a plastoquinone pool. The reaction sequence in system II leads to water cleavage into O2 and hydrogen bound to plastoquinone (PQH2). Subsequent reactions supported by photosystem I enhance the electronic energy of metabolically bound hydrogen from the level of PQH2 up to that of nicotinamide adenine dinucleotide phosphate hydride. A high quantum efficiency of the reaction center processes requires a delicate balance of the rate constants for the forward and back reaction of each individual transfer step. This essential problem is obviously solved by selection of appropriate redox groups that are incorporated into a special protein matrix, so that a definite mutual electronic coupling arises. A complete understanding of the molecular mechanism of photosynthetic water oxidation can be only achieved if dynamic structural changes occurring in the apoenzyme are unraveled, because in well characterized enzymes redox changes are known to be coupled with functional significant structural changes.

The dual of the set of all uniform covers of a uniform space is characterized by lattice-theoretical properties within the completely distributive lattice of all stacks of the underlying set. This representation can be extended to an adjunction between the category of uniform spaces and uniformly continuous maps and a category of completely distributive lattices with specified bases and grills and complete homomorphisms preserving these structure-sets.

In order to investigate South Atlantic paleocirculation and the tectonic and sedimentary history of the Rio Grande rise, D/V Glomar Challenger occupied four sites during Deep Sea Drilling Project (DSDP) Leg 72: Site 515 in the Brazil basin, Site 516 near the crest of the Rio Grande rise, and Sites 517 and 518 on the lower western flank of the rise. Site 515 recovered sediments deposited by Antarctic Bottom Water (AABW) entering the Brazil basin through the Vema channel. We penetrated 617 m of rapidly accumulated, terrigenous and siliceous muds and mudstones before encountering an unconformity spanning 20 to 25 m.y. between the late Oligocene and early Eocene. The hiatus brackets the time of the proposed onset of AABW flow in the southwestern Pacific at ∼37 m.y.; however, evidence in the sediments at Site 515 suggests the presence of bottom-water circulation in the Brazil basin by early Eocene time. Sites 517 and 518 recovered calcareous sediments deposited under the influence of AABW and North Atlantic Deep Water (NADW) within the Vema channel. At both sites, an increase in the abundance of the AABW indicator species N. umbonifera during the late Pliocene implies that AABW extended to significantly shallower depths at that time than it does today. Detailed carbonate analyses at Site 518 may extend the late Pleistocene climatic signal through the entire Pleistocene and perhaps into the Miocene. At Site 516, near the crest of the Rio Grande rise, we penetrated 1,250 m of dominantly calcareous sediments and 21 m of basaltic basement rocks of Santonian-Coniacian age. With the exception of some minor hiatuses in the middle and late Miocene, sedimentation at this site was continuous for the past 80 m.y. Magneto-stratigraphic and biostratigraphic control is excellent, and the section may therefore be useful as a stratigraphic reference. The Cretaceous-Tertiary boundary was recovered intact and is directly comparable with the Italian Gubbio section. This interval may also provide some new evidence pertaining to the proposed association between mass extinctions and geochemical anomalies at the boundary. The igneous basement rocks recovered at Site 516 are T-type Mid-Ocean Ridge basalts (MORB), similar to those found on Iceland, and are unlike the alkalic basalts exposed on Tristan da Cunha. Their chemistry, together with the occurrence of shallow-water fossils in vein fillings, suggests that these basalts were erupted on an anomalously shallow part of the Mid-Atlantic Ridge. A Santonian-Coniacian age for basement is inferred from the age of the overlying sediments and is consistent with the identification of magnetic anomalies 33 and 34 on the rise to the east of the site. The basal sediments and underlying volcanic basement recovered at Site 516 may provide constraints on the subsidence history of the Rio Grande rise. However, this history may have been complicated by a middle Eocene episode of tectonic and volcanic activity, as suggested by ash layers, volcaniclastic sediments, and slump blocks in the mid-Eocene sediment section. The occurrence of reef debris in this interval implies that the uppermost part of the rise was very shallow and perhaps subaerial during this time.