Structural characterization of a novel KH-domain containing plant chloroplast endonuclease.

Chlamydomonas reinhardtii is a single celled alga that undergoes apoptosis in response to UV-C irradiation. UVI31+, a novel UV-inducible DNA endonuclease in C. reinhardtii, which normally localizes near cell wall and pyrenoid regions, gets redistributed into punctate foci within the whole chloroplast, away from the pyrenoid, upon UV-stress. Solution NMR structure of the first putative UV inducible endonuclease UVI31+ revealed an α1-ß1-ß2-α2-α3-ß3 fold similar to BolA and type II KH-domain ubiquitous protein families. Three α-helices of UVI31+ constitute one side of the protein surface, which are packed to the other side, made of three-stranded ß-sheet, with intervening hydrophobic residues. A twenty-three residues long polypeptide stretch (D54-H76) connecting ß1 and ß2 strands is found to be highly flexible. Interestingly, UVI31+ recognizes the DNA primarily through its ß-sheet. We propose that the catalytic triad residues involving Ser114, His95 and Thr116 facilitate DNA endonuclease activity of UVI31+. Further, decreased endonuclease activity of the S114A mutant is consistent with the direct participation of Ser114 in the catalysis. This study provides the first structural description of a plant chloroplast endonuclease that is regulated by UV-stress response.

Transdisciplinary translational behavioral (TDTB) research: opportunities, barriers, and innovations.

The translation of basic behavioral science discoveries into practical strategies represents a promising approach to developing more effective preventive interventions to improve health. Since translational research inevitably involves making use of diverse perspectives from multiple disciplines, it is best conducted as a transdisciplinary enterprise. In this paper, we discuss current strategies used by NIH to support transdisciplinary translational behavioral (TDTB) research, summarize successful efforts, and highlight challenges encountered in conducting such work (ranging from conceptual to organizational to methodological). Using examples from NIH-funded projects we illustrate the potential benefits of, and barriers to, pursuing this type of research and discuss next steps and potential future directions for NIH-supported TDTB research.

Sequence specific 1H, 13C and 15N backbone resonance assignments of UVI31+ from Chlamydomonas reinhardtii.

The cDNA of UVI31+ was cloned from C. reinhardtii and expressed in E. coli from where the protein was purified to homogeneity. The purified protein exhibited beta-lactamase activity (Manuscript in preparation). However, UVI31+ has no homology with the known ß-lactamases. In order to understand the structural basis of the ability of UVI31+ to hydrolyze ß-lactam antibiotics, we in parallel, set out to structurally characterize it by NMR. Its ß-lactamase activity in relation to the solution structure by NMR is likely to provoke deeper understanding of its mechanism and facilitate the rationalization of other functions of the protein, if any. In this endeavor, we report almost complete sequence-specific backbone (1)H, (13)C and (15)N NMR assignments of UVI31+.

[Primary leptomeningeal sarcomatosis in a 26-year-old patient]. / Primäre Leptomeninxsarkomatose bei einem 26 Jahre alten Patienten.

Primary malignant mesenchymal tumours were seen in 2.4 per cent of all autopsy cases with primary CNS-tumours. Primary leptomeningeal sarcomatosis is rare in this group of tumours. We discuss the rare disease on the basis of the case history of a 26-year-old patient.

[Intrauterine stab injury with a knife in the head of a fetus in the 29th week of pregnancy]. / Intrauterine Messerstichverletzung des Kopfes bei einem Feten in der 29. Schwangerschaftswoche.

Penetrating head trauma in children causes uncommon and potentially life-threatening injuries. We report on a case of penetrating cranial stab wound to the right parietal region of the head to a 29-week fetus. The child was delivered by emergency Caesarian section. Neurosurgical intervention after birth was necessary. The injury caused a posthaemorrhagic hydrocephalus. Real-time ultrasound examination visualises the brain damage and the development of a hydrocephalus e vacuo.

[Primary melanoblastoma as a cause of occlusive hydrocephalus]. / Primäres Melanoblastom als Ursache eines Okklusivhydrocephalus.

Primary melanoblastomas of the Central Nervous System are comparatively rare tumors. Lumpy or diffuse forms may occur either alone or in combination. On the basis of actual case histories, diffuse cerebral and medullary melanoblastoma is presented as a rare cause of occlusive hydrocephalus.

[Surgical treatment possibilities in cerebrovascular insufficiency--status and future prospects]. / Die chirurgischen Behandlungsmöglichkeiten der zerebrovaskulären Insuffizienz--Stand und Ausblick.

After a short synopsis of the at present ascertained knowledge of the anatomy and pathophysiology of the cerebral blood supply the possibilities of the vascular-surgical treatment are discussed. The desobliteration of extracranial vessels, PTA, vascular resections and appliances of bypass are no concurrent operation techniques, but such ones which are individually to be adapted. The importance of the clinical and non-invasive diagnostics is put before the digital subtraction angiography and the direct angiography. On the basis of the experience of 461 own surgical interventions the stage-conditioned diagnosis is required. Stage II of the transitory ischaemic attack is preferred. In unilocular mediastenoses the extra-intracranial anastomosis now as ever hat its qualification.

[Correlation between clinical and paraclinical findings in brain tumors in comparison with the operation site]. / Die Korrelation zwischen den klinischen und paraklinischen Befunden bei Hirntumoren im Vergleich zum Operationssitus.

On the basis of clinical material consisting of 147 brain tumors, the authors carry out a comparative investigation involving the site of the ensuing operation to ascertain the accuracy of the clinical and paraclinical diagnoses. Computed tomographic findings were deliberately excluded with the intention of focusing on the accuracy attainable by traditional means. Clinical findings, X-ray examination of the skull, ophthalmological findings, electroencephalographic and echoencephalographic data, nuclear diagnosis, and angiographic findings were all taken into account.

[Injuries of the basilar artery]. / Verletzungen der Arteria basilaris.

In 2 to 3 per cent of the severe craniocerebral occlusions of the cerebral basic arteries are observed. Traumatic vertebralis and basilaris thromboses are very rare. In view of the modern procedure in diagnostics and therapy the prognosis of these life-threatening traumatic consequences are not infaust. According to a casuistic information pathophysiology, diagnostic procedure and therapeutical possibilities, microsurgical or by local fibrinolysis, are discussed.

[Late results following treatment of peripheral nerve injuries of the upper extremity]. / Spätergebnisse nach Behandlung peripherer Nervenverletzungen der oberen Extrimität.

The authors re-examine cases of complete peripheral nerve injury of the upper extremity. Motor activity and sensibility assessment make use of Highet's scale. Some general principles of surgical treatment of peripheral nerve injuries are presented and individual factors which influence its results are worked out, e.g. moment of diagnosis, kind of nerve suture, moment of operation, age of patient, grade of injury, concomitant injuries, and length of graft. Conclusions are drawn for the concept of treatment.

[Transdural penetration of sequestered hernias of lumbar intervertebral disks]. / Zum transduralen Vordringen sequestrierter lumbaler Bandscheibenhernien.

Long-lasting, high-degree, degenerative alterations of the vertebral column and the abnormal fixation of the dural sac as pathogenetic factors of a transdural advancing of sequestered lumbar hernia of the intervertebral disks are discussed.

[Delayed encephalopathy]. / Delayed encephalopathy.

A specific clinical course of light covered craniocerebral traumas patients, corresponding to 2 per cent of all clinically treated craniocerebral traumata. Twilight states and transient neurological and ophthalmological symptoms characterise the clinical picture. The prompt reversibility of the symptoms indicates a functional damage requiring a differential-diagnostic consideration of morphological sequelae of traumas, for which instrumental diagnostics and, if required, surgical consequences are necessary.

Mitochondrial respiratory function as indicator of the ischemic injury of the rat kidney.

The function of mitochondria was considered to be an indicator of ischemic injury of the rat kidney, and the respiration of isolated mitochondria was measured in different metabolic states. The respiratory control index (RCI) was chosen as a parameter of mitochondrial intactness. The results indicate that normothermic in vitro ischemia leads to a rapid decrease of RCI and an almost complete loss of respiratory control within 45 min. Hypothermia during ischemic exposure proved to be an effective protection against mitochondrial injury as indicated by a prolonged coupled respiration and an RCI of about 2, even after 24 h of ischemic kidney storage. The ischemia-induced decrease of RCI was mainly due to a progressive decrease of active-state respiration, whereas the alterations of resting-state respiration were only small. The decline of active-state respiration was paralleled by a decrease of an uncoupled respiration rate. After termination of in vivo ischemia the RCI increased very slowly. Normal RCI values were not obtained until 7 days after onset of blood reflow, which supports the assumption of long-term damage due to ischemia.

[Artificial stenosis of the left vertebral artery in the rabbit]. / Die artifizielle Stenosierung der A. vertebralis sinistra beim Kaninchen.

Animal experiments were carried out to clarify if a unilateral stenosis of the vertebral artery leads to a typical symptomatology and if a surgical therapy may be promising. The left vertebral artery was stenosed in 12 rabbits. The result was checked for 3 weeks electro-encephalographically and doppler-sonographycally. Conclusions after this long-term experiment: 1) A unilateral stenosis of the vertebral artery leads to a brain stem symptomatology. 2) This symptomatology shows determined development in dependence of the time. 3) Correlates of the brain stem lesion by vertebral stenosis were discovered electroencephalographically they were increased by specific activation methods. 4) The expected success produced the operative removal of the artificial stenosis of the vertebral artery. 5) The blood flow of the vessels which are of interest could be controlled by means of the ultrasound doppler-sonography during the whole experiment.

[Ultrasonic Doppler technic as a method of functional control of extracranial-intracranial anastomosis]. / Die Ultraschall-Doppler-Technik als Methode zur Funktionskontrolle der extra-intrakraniellen Anastomose.

The authors describe the use of the ultrasound Doppler technique for the postoperative control of extra-intracranial bypasses. They arrive at the result that the Doppler sonography, because of an agreement of sonographic and angiographic findings 85 per cent, should be given preference. Moreover, an ultrasonic examination does not involve any inconvenience or risks for the patient.