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Background: Fournier's gangrene (FG) is an acute urological emergency described as a necrotising soft-tissue infection of the genitalia and perineum with associated polymicrobial infection, organ failure and death. The use of broad-spectrum antibiotics and immediate surgical debridementare the mainstays of treatment. The extensive debridement of all the necrotic tissue, the associated wound care and the reconstruction of the defect remain a big challenge. The prevalence in low-income countries such as South Africa seems to be higher when compared to international statistics despite the lack of published data. Patients and methods: A descriptive retrospective study was performed for the period of January 2006 up to December 2015 at Kimberley Hospital Complex, a facility which provides tertiary services to the Northern Cape Province (NCP) in South Africa. A search for all patients who underwent reconstructive procedures following the successful management of FG was performed using the Department of Plastic and Reconstructive Surgery's database. Challenges and pitfalls for the performance of the reconstruction were analysed. Results: Sixty-four male patients underwent genital reconstruction after FG debridement. The age range was 16 to 78 years (mean 52.75). Fifty-six (87.5%) of the patients were referred from rural areas of the NCP. Fifty-nine (92.2%) were reconstructed with split-thickness skin grafting; of these 14% had initial partial graft failure. Most patients were referred from rural areas after debridement with suboptimal wound care and lack of management of the testicles which needed to be optimised before the reconstructive procedure. Conclusions: Due to this high prevalence, lack of resources and severity of the disease, many general practitioners are expected to assist the patient diagnosed with FG by performing the initial and life-saving debridement. This proves to be a challenge for the less experienced doctor, who is expected to refer the patient to other centres for reconstructive procedures. Based on our experience, we analysed the challenges and pitfalls encountered and provided some strategies for the referring practitioner to perform surgical management for a better reconstructive outcome. [ABSTRACT FROM AUTHOR]

Introduction: The surgical and reconstructive management of malignant tumours of the head and neck have always presented unique challenges, particularly as they occur in such a cosmetically significant area. The aim for surgical resection emphasises adequate oncological control of the tumour, which often leaves large soft tissue defects requiring complex surgical techniques for reconstruction. In this report the authors present a case of a dermatofibrosarcoma protuberans in the head and neck which was resected, leaving a large superficial soft tissue defect in the neck and face. Reconstruction and closure of the defect was achieved with a combination of a regional fasciocutaneous flap, dermal regeneration template and later skin grafting. Materials and methods: A 65-year-old female patient presented to the Kimberley Hospital Complex. The patient underwent a wide local excision of a head and neck dermatofibrosarcoma protuberans by the Department of Maxillofacial Surgery followed by surgical reconstruction by the Department of Plastic and Reconstructive Surgery. Results: The combined approach of a regional fasciocutaneous flap, dermal regeneration template and skin graft were used to achieve an aesthetically adequate closure of the large wound left after excision of the head and neck tumour. Conclusion: This presented technique provides a good reconstructive option for the management of soft tissue head and neck tumours which leave large defects following resection with curative objectives, particularly in settings such as ours where more complex reconstructive techniques are limited by a combination of factors. [ABSTRACT FROM AUTHOR]

Monofilamentary MgB2-wires with a 2- or 3-component sheath containing mechanical reinforcing stainless steel (SS) were prepared and characterized. In direct contact to the superconductor Nb, Ta or Fe was used. For a selection of samples with a Fe and Fe/SS sheath, we investigated the transport critical current behaviour in magnetic fields changing systematically the geometrical shape from a round wire to a flat tape. A strong increase of the current densities in flat tapes was observed and possible reasons for this are discussed. Reinforcing the sheath in the outer layer with different amounts of stainless steel leads to a systematic field dependent decrease of the transport critical current density with increasing steel amount. This is an indication for a pre-stress induced degradation of the critical currents in MgB2 wires and first Ic–stress–strain experiments seem to confirm this observation and interpretation. [Copyright &y& Elsevier]

Describes a 3-chamber deposition system for the simultaneous double-sided coating of high temperature superconducting (HTS) wafers. Temperature variation; Thickness distribution of YbaCuO films; Composition of deposited HTS films.

Although Al(III) hydrolysis, condensation, and nucleation play pivotal roles in the synthesis of Al-based compounds and determine their chemical behavior, we still lack experimental evidence regarding the chemistry of nucleation from solution. Here, by combining advanced titration assays, high-resolution transmission electron microscopy (HR-TEM), and 27 Al-nuclear magnetic resonance spectroscopy, we show that highly dynamic solute prenucleation clusters (PNCs) are fundamental precursors of nanosolid formation. Chemical changes from olation to oxolation bridging within PNCs rely on the formation of tetrahedral AlO 4 in solution and trigger phase separation at low driving force (supersaturation). This does not include the formation of Keggin-Al 13 ions, at least during the earliest stages. The PNC pathway of the formation of Al(III) (oxy)(hydr)oxides offers new possibilities toward the development of strategies for controlling the entire crystallization process., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

In situ liquid phase scanning/ transmission electron microscopy (LP-S/TEM), enables direct observation of particle formation and evolution in the hydrated liquid state. Though powerful, this technique has significant technical limitations, which need to be carefully addressed in order to obtain reliable quantitative data. In this paper, we highlight several common challenges seen in LP-TEM, including electron-beam induced particle dissolution and motion, particle-membrane adhesion, contamination, and triggering of reactions. We describe our efforts to address these challenges by modifying solution and interface chemistry, maintaining solution flow, performing systematic post in situ analyses on the samples and applying controlled heating., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

We present observations of the radiation belts from the Helium Oxygen Proton Electron and Magnetic Electron Ion Spectrometer particle detectors on the Van Allen Probes satellites that illustrate the energy dependence and L shell dependence of radiation belt enhancements and decays. We survey events in 2013 and analyze an event on 1 March in more detail. The observations show the following: (a) at all L shells, lower energy electrons are enhanced more often than higher energies; (b) events that fill the slot region are more common at lower energies; (c) enhancements of electrons in the inner zone are more common at lower energies; and (d) even when events do not fully fill the slot region, enhancements at lower energies tend to extend to lower L shells than higher energies. During enhancement events the outer zone extends to lower L shells at lower energies while being confined to higher L shells at higher energies. The inner zone shows the opposite with an outer boundary at higher L shells for lower energies. Both boundaries are nearly straight in log(energy) versus L shell space. At energies below a few 100 keV, radiation belt electron penetration through the slot region into the inner zone is commonplace, but the number and frequency of "slot filling" events decreases with increasing energy. The inner zone is enhanced only at energies that penetrate through the slot. Energy- and L shell-dependent losses (that are consistent with whistler hiss interactions) return the belts to more quiescent conditions.

One of the most unsettled problems of prebiotic evolution and the origin of life is the explanation why one enantiomeric form of biomolecules prevailed. In the experiments presented in this paper, the influence of L-histidine on the peptide formation in the Salt-Induced Peptide Formation (SIPF) reaction of the enantiomeric forms of valine, proline, serine, lysine, and tryptophan, and the catalytic effects in this first step toward the first building blocks of proteins on the primordial earth were investigated. In the majority of the produced dipeptides, a remarkable increase of yields was shown, and the preference of the L-amino acids in the peptide formation in most cases cannot be denied. In summary, our data provide further experimental evidence for the plausibility of the SIPF reaction and point at a possible important role of L-histidine in the chemical evolution on the primordial Earth.

For more than 50 years scientists who study prebiotic chemistry have been dealing with chemical evolution as it could have possibly taken place on the primordial Earth. Since we will never know what processes have really taken place around 3.8 to 4 billion years ago we can only come up with plausible reaction pathways that work well in an early Earth scenario as indicated by geochemists. In our work we have investigated the plausibility of one particularly important branch of prebiotic chemistry, the formation of amino acids, by electric discharge in a neutral atmosphere composed of carbon dioxide, nitrogen, and water vapour above liquid water. We have found yields of various amino acids under different temperature conditions, with and without sodium chloride in a simulated primordial lake or ocean within extremely short reaction times compared to the timespan available for prebiotic evolution.

"Mutual" amino acid catalysis of glycine on the formation of ditryptophan, dilysine, and diserine in the prebiotically relevant Salt-Induced Peptide Formation (SIPF) Reaction was investigated varying the starting concentration and chirality of the educt amino acid, and analyzing the increase of yield resulting from this catalytic effect. Our results show the possibility of an amplified diverse pool of peptides being available for chemical evolution of larger peptides and proteins using also these more complicated amino acids for the evolution of more complex functions in future biochemical cycles and thus for the emergence of life. Catalytic effects are especially high in the case of serine, the most basic amino acid of the three, but are also significant for the other two examples investigated in the present work. Besides that, especially for serine, but also in the case of tryptophan, differences in catalytic yield increase according to the chiral form of the amino acid used could be observed.

The catalytic effects of the simple amino acid glycine on the formation of diproline and divaline in the prebiotically relevant salt-induced peptide formation (SIPF) reaction was investigated in systems of different amino acid starting concentrations and using the two enantiomeric forms of the respective amino acid. Results show an improved applicability of the SIPF reaction to prebiotic conditions, especially at low amino acid concentrations, as presumably present in a primordial scenario, and indicate excellent conditions and resources for chemical evolution of peptides and proteins on the early earth. For valine, furthermore differences in catalytic yield increase are found indicating a chiral selectivity of the active copper complex of the reaction and showing a connection to previously found enantiomeric differences in complex formation constants with amino acids.

All living organisms on earth are almost totally made up of biomolecules of only one chiral form. For example, proteins are built almost exclusively of L-amino acids, and sugars are composed of D-saccharides, a fact that is usually referred to as biohomochirality. Its origin is the center of numerous investigations and theories but is not really elucidated yet. The results of experimental investigations of peptide formation in a prebiotically relevant scenario, as described in this paper, give indications on a possible pathway for the synthesis of homochiral L-peptides in the course of the Salt-induced Peptide Formation (SIPF) reaction.

To re-enact the long way to the origin of life with today's chemical methods, many steps have to be investigated in the light of a primordial scenario deduced from geochemical research. After the formation of our planet and its atmosphere, prebiotic chemical evolution started its course with the formation of the first building blocks for the formation of biomolecules. In the case of proteins, those building blocks were amino acids that had to be formed in the primitive atmosphere, and then had to react to peptides and proteins as the main pillar of first life. In this paper, we describe the processes in the primordial atmosphere according to contemporary geochemical knowledge leading to the synthesis of amino acids until the formation of homochiral peptides, and, thus, show a plausible pathway towards the origin of life.

Pegylated polystyrene particles (PS-PEG) were prepared as a model system for artificial cells, by modification of carboxyl polystyrene particles (PS-COOH) with homo- and hetero-bifunctional polyethylene glycols (PEG, MW 1500, 3400, and 5000) containing an amino end group for immobilization and an amino, hydroxyl, or methoxy end group that is exposed at the surface after immobilization. Protein adsorption from human plasma dilutions (85 v %) onto PS-PEG with a PEG surface concentration higher than 40 pmol/cm2 was reduced up to 90-95% compared with protein adsorption onto PS-COOH with a final protein surface concentration of approximately 30 ng/cm2. Two-dimensional gel electrophoresis analyses showed that 30% of the total amount of adsorbed proteins onto PS-PEG are dysopsonins (i.e., nonadhesive proteins like albumin and apolipoproteins). For PS-COOH, <15% of the amount of adsorbed proteins are dysopsonins. In addition, the generation of terminal complement compound (TCC) by PS-PEG particles with a PEG surface concentration lower than approximately 55 pmol/cm2 is not significant. The low protein adsorption, the relatively high percentage of adsorbed dysopsonins, and the low level of complement activation may prevent the uptake of PS-PEG by the mononuclear phagocytic system (MPS) in vivo. Moreover, PS-PEG (PEG surface concentration > approximately 35 pmol/cm2) shows minimal interaction with cultured human umbilical vein endothelial cells (HUVEC), which mimics the endothelial lining of the blood vessel wall., (Copyright 2004 Wiley Periodicals, Inc.)

The paper deals with the long-run development in mortality at individual ages in Germany by using a relative index of change in probabilities to die. The mortality at early childhood ages diminished to about one percent of what it was in the first German life table of 1871/81. Changes in infant mortality alone were responsible for 25 percent of the total increase in "life expectancy at birth" in the observation period. Changes in mortality at ages below 10 accounted for roughly 50 percent of change in life expectancy at birth. In the second part of the paper the measurement concept is used to evaluate assumptions about the future course of mortality in Germany. The most recent official forecast by the German Statistical Office is used to demonstrate the principle. The official assumptions about the future mortality proof to be unrealistically conservative. At ages below 20 the latest available data on mortality are more favorable than what is assumed for the year 2050.

It is reported on alterations of ECG and blood pressure appearing in 51 patients during endoscopic examination of the stomach. Above all, these alterations consisted of repolarisation disturbances with a partial preterminal negative T and isolated supraventricular extrasystoles. Atrioventricular blocks or spreading of the QRS-complex were not observed. In all patients a distinct increase in frequency was present while the endoscope was introduced. Since regression of all these alterations would occur after examination, a vegetative-functional stimulus might be the inducing factor. In endoscopic examinations the risk of any incidents appearing in connection with the system of coronary circulation is minimal. In patients with considerable previous damage of the heart caution is advised.

The results of a study with tamoxifen (TAM) (10 mg three times daily) in advanced breast cancer are reported. Of 44 patients, 24 showed a remission and 20 a progression. Of the 17 patients in whom an oestrogen receptor (ER) determination in tumour tissue had been carried out, 12 were receptor-positive (ER+) and five receptor-negative (ER-). Nine of the 12 ER+ cases (75%) responded to the treatment with TAM. Of the five ER- patients, one showed remission and four progression.

The vast amount of so-called antirheumatics that have flooded the pharmaceutical market in recent time makes it practically impossible for the physician to distinguish between positive and negative therapeutical effects of these drugs. We have therefore tried, based upon the pharmaco-dynamical and pharmaco-kinetical results as well as clinical experience, to give rational advice as to application of antirheumatic substances in general practice. It has shown, that as in all of the subdivisions of pharmatherapeutics the best therapy is to treat patients with only a small contingent of name drugs, whose side-effects and dangers are exactly known.