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The well-studied enterobacterium Escherichia colipresent in the human gut can reduce trimethylamine N-oxide (TMAO) to trimethylamine during anaerobic respiration. The TMAO reductase TorA is a monomeric, bis-molybdopterin guanine dinucleotide (bis-MGD) cofactor-containing enzyme that belongs to the dimethyl sulfoxide reductase family of molybdoenzymes. We report on a system for the in vitroreconstitution of TorA with molybdenum cofactors (Moco) from different sources. Higher TMAO reductase activities for TorA were obtained when using Moco sources containing a sulfido ligand at the molybdenum atom. For the first time, we were able to isolate functional bis-MGD from Rhodobacter capsulatusformate dehydrogenase (FDH), which remained intact in its isolated state and after insertion into apo-TorA yielded a highly active enzyme. Combined characterizations of the reconstituted TorA enzymes by electron paramagnetic resonance spectroscopy and direct electrochemistry emphasize that TorA activity can be modified by changes in the Mo coordination sphere. The combination of these results together with studies of amino acid exchanges at the active site led us to propose a novel model for binding of the substrate to the molybdenum atom of TorA.

Photon pairs from spontaneous parametric down-conversion (SPDC) are important for a wide range of quantum optics experiments with spectral properties such as their bandwidths often being a crucial concern. Here we show the generic existence of particular phase-matching conditions in quasi-phase-matched KTP, MgO:LN, and SLT crystals that lead to ultra-broadband, widely nondegenerate photon pairs. It is based on the existence of group-velocity-matched, far apart wavelength pairs and, for 2 mm long crystals, results in SPDC bandwidths between 15 and 25 THz for photon pairs with the idler photon in the technologically relevant mid-IR range of 3–5 μm and the signal photon in the near-IR below 1100 nm. We experimentally demonstrate this type of broadband phase matching in ppKTP crystals for photon pairs centered at 800 and 3800 nm and measure a bandwidth of 15 THz. This novel method of generating broadband photon pairs will be highly beneficial for SPDC-based imaging, spectroscopy, refractometry, and optical coherence tomography with undetected mid-IR photons.

The Mo/Cu-dependent CO dehydrogenase (CODH) from Oligotropha carboxidovoransis an enzyme that is able to catalyze both the oxidation of CO to CO2and the oxidation of H2to protons and electrons. Despite the close to atomic resolution structure (1.1 Å), significant uncertainties have remained with regard to the reaction mechanism of substrate oxidation at the unique Mo/Cu center, as well as the nature of intermediates formed during the catalytic cycle. So far, the investigation of the role of amino acids at the active site was hampered by the lack of a suitable expression system that allowed for detailed site-directed mutagenesis studies at the active site. Here, we report on the establishment of a functional heterologous expression system of O. carboxidovoransCODH in Escherichia coli. We characterize the purified enzyme in detail by a combination of kinetic and spectroscopic studies and show that it was purified in a form with characteristics comparable to those of the native enzyme purified from O. carboxidovorans. With this expression system in hand, we were for the first time able to generate active-site variants of this enzyme. Our work presents the basis for more detailed studies of the reaction mechanism for CO and H2oxidation of Mo/Cu-dependent CODHs in the future.

Have you ever stood at a commuter train station when a diesel hauled consist pulls in and felt the heat pouring off the railcar wheels? With no ability to utilize […]

Die salutogene Wirkung von Religiosität und Spiritualität scheint vor allem in den letzten Jahren durch die Literatur gut belegt. Wenige Studien sind allerdings zur Wirksamkeit einer spirituell basierten therapeutischen Intervention bei psychiatrischen PatientInnen durchgeführt worden. Aus diesem Grund wurde in dieser Pilotstudie erstmals der Effekt einer morgendlichen, Körper-zentrierten Meditation auf das psychische Befinden, und die Möglichkeiten der Stressverarbeitung im Vergleich zu dem im Therapieplan vorgesehenen Morgenspaziergang untersucht. 44 (26 Frauen) nach ICD 10 diagnostizierte stationär-psychiatrische PatientInnen wurden randomisiert zu den beiden Interventionen zugewiesen und jeweils zu Beginn und Ende der sechswöchigen Therapie hinsichtlich ihrer Befindlichkeit mittels standardisierter Fragebögen befragt. Insgesamt kann ein signifikanter Anstieg im religiös/spirituellen Wohlbefinden, in der Achtsamkeit bzw. in adäquateren Strategien zur Krankheitsverarbeitung berichtet werden. Dies ging mit einem Abklingen der psychiatrischen Symptombelastung einher. Des Weiteren wurde der allgemein postulierte positive Zusammenhang zwischen Spiritualität und psychischer Gesundheit bestätigt. Es ergaben sich allerdings keine Unterschiede zwischen den beiden Behandlungsmethoden (Meditation vs. Spaziergang). Beide Interventionen zeigten somit einen gleich hohen positiven Effekt. Basierend auf diesen ersten Erkenntnissen können Möglichkeiten und Grenzen der Integration spiritueller Inhalte in die Behandlung von psychiatrischen PatientInnen diskutiert werden. In recent years, positive effects of religiosity and spirituality on mental health can be found as well documented in the literature. However, very few studies have examined the effects of a spiritually based therapeutic intervention among psychiatric patients. For this reason, in this pilot study we examined the effectiveness of a morning body-centered meditation in comparison to a conventional morning walk in regards to subjective well-being and stress coping styles in 44 (26 females) randomly assigned psychiatric in-patients (according to ICD 10). The patients’ amount of subjective well-being as well as their coping ability was assessed at the beginning and at the end of a 6 weeks therapy. Thereby we found a significant increase in Religious/Spiritual Well-Being, Awareness and more adequate Coping strategies. This was paralleled by a decrease of psychiatric symptoms. Overall the general assumption of a positive association between spirituality and mental health was affirmed. However, we did not find any differences between the two treatment methods (meditation vs. morning walk). Both interventions showed the same positive efficacy. Based on these initial results, possibilities and boundaries for the integration of religious/spiritual issues into the treatment of psychiatric patients are discussed.

Neoadjuvant chemotherapy (NC) in patients with breast cancer results in high response rates and has been used with the purpose of reducing tumor size and achieving breast conservation (BC) in individuals who initially require mastectomy. Our objective is to determine the success of NC in achieving BC in women who initially were not candidates for BC. We conducted a cohort study of women with invasive breast cancer who required mastectomy but desired BC surgery. Outcomes measured were tumor response and rates of BC. Thirty-seven women had a mean age of 45 years. Mean tumor size was 51 mm, and 62 per cent were larger than 4 cm. Tumors were predominantly infiltrating ductal carcinoma (83.3%) and high grade (62.2%). Cyclophosphamide, doxorubicin, and 5-fluorouracil with or without taxotere were most commonly used (86%). Complete clinical and pathologic responses were seen in 32.4 per cent and 10.8 per cent of patients, respectively. BC was achieved in 56.7 per cent of cases. Only initial tumor size predicted tumor regression and success of BC (P = 0.014). Neither tumor histology nor biologic markers predicted tumor response. In conclusion, NC is an effective alternative in achieving tumor reduction and BC in selected patients who require mastectomy but desire BC surgery.

The accuracy of sentinel lymph node biopsy (SLNB) staging in breast cancer has been demonstrated in studies comparing it with axillary dissection. There is a 5 per cent false-negative rate, but this does not always correlate with axillary recurrence. Our purpose was to determine the rate of axillary lymphatic recurrence in breast cancer patients who had a negative SLNB. We conducted a cohort study of breast cancer patients who underwent SLNB between 2001 and 2005. Only patients who had a negative SLNB were included. Patient demographics and tumor factors were reviewed. Outcomes measured were axillary and systemic recurrence and survival. Eighty-nine patients with a mean age of 54.4 ± 9.9 years were included. Eighty-nine per cent of cases had infiltrating ductal carcinoma histology. Mean tumor size was 19 ± 14 mm. Breast conservation surgery was done in 65 cases and mastectomy in 24. A mean of 2.3 ± 2.4 SLN were found. After a median follow-up of 2.15 years, 1 (1%) patient developed a lymphatic recurrence in the axilla. SLNB provides accurate staging of breast cancer. Patients with negative SLNB do not require axillary dissection.

The A-not-B (AB) task has been hypothesized to measure executive/frontal lobe function; however, the developmental and measurement characteristics of this task have not been investigated. Performance on AB and comparison tasks adapted from developmental and neuroscience literature was examined in 117 preschool children (ages 23–66 months). Age significantly predicted performance on AB, Delayed Alternation, Spatial Reversal, Color Reversal, and Self-Control tasks. A four-factor analytic model best fit task performance data. AB task indices loaded on two factors with measures from the Self-Control and Delayed Alternation tasks, respectively. AB indices did not load with those from the reversal tasks despite similarities in task administration and presumed cognitive demand (working memory). These results indicate that AB is sensitive to individual differences in age-related performance in preschool children and suggest that AB performance is related to both working memory and inhibition processes in this age range.

The influence of severity of closed head injury and age on attentional functioning was prospectively investigated in 36 children (age range, 7 to 16 years) 6 months after injury. Children were placed into mild, moderate, and severe injury groups using established neurologic criteria. Each child received the Wechsler Intelligence Scale for Children-Revised Digit Span subtest and a continuous performance test. Children with severe closed head injury demonstrated significantly poorer continuous performance test scores than mildly or moderately injured children. Injury severity had no effect on Digit Span scores. Younger children exhibited more pronounced impairment on the continuous performance test relative to uninjured age peers. These results extend the persistence of attentional impairments beyond those of previous reports. Closed head injury is not associated with preferential sparing of sustained attention in younger children 6 months after injury. Brain injury earlier in life may result in delayed vulnerability of information processing skills. (J Child Neurol1993;8:348-353).

Everyone knows what attention is. It is the taking possession by the mind, in clear and vivid form, of one out of what seem to be several simultaneously possible objects or trains of thought. Focalization, concentration, and consciousness are of its essence. (James, 1890, pp. 381-382)

Deficits in pragmatic communication ability have a significant impact on functional outcome from traumatic brain injury (TBI), particularly during adolescence, when sophisticated social communication skills are developing. There are few published tests designed to assess pragmatic skills in this age group. In the present study, four tasks designed to tap various aspects of pragmatic communication ability were administered to three brain-injured adolescents and 36 of their uninjured peers aged 15-18 years. The tasks evaluated the ability to negotiate, hint, describe a simple procedure, and understand sarcasm. The four tasks were found to tap distinct aspects of pragmatic ability in control subjects. Further, within the control group, task performance was related more to non-verbal reasoning ability than vocabulary skills. Scores for two of the three TBI subjects were poorer than those of their peers, while a third mildly injured subject performed within normal limits. Pragmatic task scores were consistent with the results of neuropsychological testing in the three TBI subjects. Implications for clinical management and recommendations for future research are discussed.

Zusammenfassung Für die Flugplanung gewinnen derzeit Vertikalschnitte durch die atmosphärische Strömung vermehrte Bedeutung. Obwohl die fliegerischen Ansprüche g gesteigert sind, wird man sich mit der Bestimmung geostrophischer Winde begnügen müssen. Zur Konstruktion aktueller Querschnitte aus wenigen Angaben wird die Verteilung der geostrophischen Winde berechnet. Ein praktisches Verfahren setzt die Tabellierung der Ergebnisse voraus. Die prognostischen Querschnitte gehen aus der Veränderung der örtlichen Temperaturschichtung hervor. Diese wird im zweiten Teil behandelt. Ein routinemässiges Verfahren ist nur im Zusammenhang mit graphischer oder numerischer Prognostik denkbar.