2,745 research outputs found
The L-amino acid oxidase of Neurospora
In 1944 one of us described a D-amino acid oxidase in extracts of Neurospora crassa (1). Except for slight activity against L-glutamate, no oxidation of L-amino acids was observed. Recently a means for inducing the formation of a soluble L-amino acid oxidase by the mold was reported by Bender, Krebs, and Horowitz (2). This is accomplished by reducing the biotin content of the basal medium (3) from the 5 γ per liter usually employed to 0.25 γ per liter. When cultured in such a medium, Neurospora produces an active L-amino acid oxidase which can be demonstrated both in extracts and in the medium. Reduction of the biotin level produces no effect on the D-amino acid oxidase, which is still found in extracts but not in the culture medium. The activity of the L-oxidase toward thirty-eight amino acids has been investigated by Bender and Krebs (4).
The initial purpose of the present investigation was to explore certain possibilities for a genetic study of the enzyme. Of special interest was the fact, cited by Bender et al. (a), that the oxidase could not be detected in all of the wild type strains tested. The question arose as to whether this is due to the genetic inability of certain strains to form the enzyme. In connection with the investigation of this problem a general survey of the properties of the enzyme was carried out, together with a preliminary study of the mechanism of the biotin effect and of the adaptive formation of the enzyme. The results of these studies are reported below.
Simultaneously with our investigation and independently of it, Dr. K. Burton (5), working in Professor Krebs’ laboratory, has carried out a study of the Neurospora L-amino acid oxidase. Where our respective studies overlap mutual confirmation was obtained in most essential points. We wish to thank Dr. Burton for permission to read his manuscript before publication
First Evaluation of an Index of Low Vagally-Mediated Heart Rate Variability as a Marker of Health Risks in Human Adults: Proof of Concept.
Multiple studies have demonstrated low vagally-mediated heart rate variability (HRV) being associated with a range of risk factors for heart disease and stroke, including inflammation, hyperglycemia, hyperlipidemia, and hypertension. Yet, no cut point exists that indicates elevated risk. In the present study we sought to identify a cut point-value for HRV that is associated with elevated risk across a range of known risk factors. METHODS:A total of 9550 working adults from 19 study sites took part in a health assessment that included measures of inflammation, hyperglycemia, hyperlipidemia, and hypertension and vagally-mediated HRV (Root mean square of successive differences between normal heartbeats (RMSSD)). Multiple age and sex adjusted logistic regressions were calculated per risk factor (normal versus clinical range), with RMSSD being entered in binary at different cut points ranging from 15-39 msec with a 2 msec increment. RESULTS:For daytime RMSSD, values below 25 ± 4 indicated elevated risk (odds ratios (OR) 1.5-3.5 across risk factors). For nighttime RMSSD, values below 29 ± 4 indicated elevated risk (OR 1.2-2.0). CONCLUSION:These results provide the first evidence that a single value of RMSSD may be associated with elevated risk across a range of established cardiovascular risk factors and may present an easy to assess novel marker of cardiovascular risk
Use of ERTS-1 data in the educational and applied research programs of agricultural extension
There are no author-identified significant results in this report
Use of ERTS-1 data in identification, classification, and mapping of salt-affected soils in California
There are no author-identified significant results in this report
Paper Session II-B - 3-Dimensional Feature Mapping Using Spatial Spectral Analysis
Orbiter vehicles are routinely exposed to a variety of small scale debris while operating in low earth orbit. Impacts with such debris often result in surface and/or subsurface damage to orbiter windows. Current procedures require windows to be manually inspected for impact damage after each shuttle mission.
Once identified, surface damage feature depths are determined by analyzing mold impressions of the damaged areas. Subsurface damage always results in window rejection since the depths of subsurface features are deemed unmeasurable using standard mold impression measurement techniques.
This paper presents an automated optical technique for measuring the depth of small scale surface and subsurface damage features in orbiter windows. Test results based on actual orbiter window damage features are also presented
Predicting the potential value of the new discharge medicines service in England
Objectives In 2021, community pharmacies in England were commissioned to support patients post-discharge through the discharge medicines service (DMS). Past studies described the benefit of DMS in avoiding readmissions. This study aimed to estimate the impact of DMS in this respect, projecting the maximal benefit if all areas mirrored the most active region. Methods A retrospective observational study, including modelling, using DMS claims data from March 2021 to February 2022, obtained from the NHS Business Services Authority (data from all community pharmacies in England for patients discharged where hospital clinicians referred them to community pharmacy). The impact of DMS on reducing readmission during this period was estimated using previous study data and estimated maximal benefit from full implementation of the service across England. Key findings In the study period 65 634 completed DMS claims were made. Claims at Integrated Care System (ICS) area level varied from 509/10 000 admissions to 29 000 readmissions at 90 days each year. Conclusions DMS has significant potential to reduce readmissions. DMS implementation is currently variable and full implementation across all-ICS areas could increase the benefits five-fold
Use of path analysis to predict changes to community pharmacy and GP emergency hormonal contraception (EHC) provision in England
ObjectivesIn 2014/2015, 46% of community pharmacies were commissioned by local authorities to provide emergency hormonal contraception (EHC) free without prescription in England. Commissioning EHC services influences EHC prescribing from General Practice (GP)—greater community pharmacy provision reduces GP prescribing. This study aimed to examine predictors of GP and pharmacy EHC activity, describing them using path analysis. From this, commissioners and policy-makers may understand ways to influence this.Study designCross-sectional study of routinely recorded data, obtained through freedom of information requests to local authorities.SettingCommunity pharmacies and general practices in England, UK.ParticipantsAll local authorities in England were included in the study (147 areas). The study population were all girls, adolescents and women aged 12–55. Of the 147 areas, data from 80 local authorities were obtained covering an eligible female population of 9 380 153.Primary and secondary outcome measuresCorrelation between community pharmacy and GP EHC activity.ResultsData from 80 local authorities were analysed, representing 60% of the eligible female population in England. A significant negative correlation was found between rates of community pharmacy provision and GP prescribing (−0.458, p<0.000). Community pharmacy provision and the proportion of pharmacies commissioned were significantly correlated (0.461, p<0.000). A significant correlation was found between increased deprivation and community pharmacy provision (0.287, p=0.010). Standardised total effects on GP prescribing were determined from path analysis including community pharmacy provision (ß=−0.552) and proportion of pharmacies commissioned (ß=−0.299). If all community pharmacies were commissioned to provide EHC, GP EHC prescriptions could decrease by 15%.ConclusionCommunity pharmacy EHC provision has a significant influence on GP EHC prescribing. Increasing the proportion of commissioned community pharmacies should have a marked impact on GP workload. The methodology affords the possibility of examining relationships surrounding other commissioned service activity across different settings and their impact on linked care settings.</jats:sec
Effect of parasympathetic stimulation on brain activity during appraisal of fearful expressions
Autonomic nervous system activity is an important component of human emotion. Mental processes influence bodily physiology, which in turn feeds back to influence thoughts and feelings. Afferent cardiovascular signals from arterial baroreceptors in the carotid sinuses are processed within the brain and contribute to this two-way communication with the body. These carotid baroreceptors can be stimulated non-invasively by externally applying focal negative pressure bilaterally to the neck. In an experiment combining functional neuroimaging (fMRI) with carotid stimulation in healthy participants, we tested the hypothesis that manipulating afferent cardiovascular signals alters the central processing of emotional information (fearful and neutral facial expressions). Carotid stimulation, compared with sham stimulation, broadly attenuated activity across cortical and brainstem regions. Modulation of emotional processing was apparent as a significant expression-by-stimulation interaction within left amygdala, where responses during appraisal of fearful faces were selectively reduced by carotid stimulation. Moreover, activity reductions within insula, amygdala, and hippocampus correlated with the degree of stimulation-evoked change in the explicit emotional ratings of fearful faces. Across participants, individual differences in autonomic state (heart rate variability, a proxy measure of autonomic balance toward parasympathetic activity) predicted the extent to which carotid stimulation influenced neural (amygdala) responses during appraisal and subjective rating of fearful faces. Together our results provide mechanistic insight into the visceral component of emotion by identifying the neural substrates mediating cardiovascular influences on the processing of fear signals, potentially implicating central baroreflex mechanisms for anxiolytic treatment targets
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