Research needs, environmental concerns, and logistical considerations for incorporating livestock grazing into coastal upland habitat management.

Along the Gulf of Mexico (GoM) coast, natural resource managers continually struggle with managing coastal uplands due to front-end costs, prolonged maintenance, and habitat-specific ecological needs. Prescribed fire, mechanical removal, and chemical treatments are common habitat management techniques used to remove invasive species, clear understory, and achieve other management goals. However, rapid development and changing climate exacerbate the difficulty in using these techniques. A potential alternative or complementary technique is using livestock for habitat management (i.e., targeted or controlled grazing). In other regions of the world, using livestock for conservation or restoration of managed lands has shown to be a less intrusive and more financially viable alternative. To better understand the research needs, logistical, and environmental concerns related to using livestock for habitat management in the coastal uplands of the GoM, we developed and distributed a survey to three groups of land users, including natural resource managers, researchers, and livestock producers in the region. Survey results show that over 96% of respondents are interested in using livestock for habitat management, but less than 10% of respondents were aware of any information that could be used to inform grazing practices for coastal upland habitat management along the Gulf of Mexico coast. There were differences among surveyed groups, but generally small-sized cattle breeds and goats were identified as the livestock with the most potential for environmental benefit and ease of containment. General concerns and areas for further investigation were implementation (e.g., which livestock type to use and grazing intensity), logistical considerations (e.g., fencing and rotational frequency), impacts of grazing on water quality, wildlife, vegetation, and livestock nutrition. Survey respondents overwhelmingly (at least 75% of each group) indicated that livestock grazing ideally would not be a standalone management practice and should be used in conjunction with other habitat management techniques such as prescribed burns, mechanical clearing, or chemical treatments. The results of the survey could be used to develop applied research projects and guidance documents that directly address informational needs related to using livestock for habitat management of coastal uplands along the Gulf of Mexico coast.

Distinct molecular signatures in pediatric infratentorial glioblastomas defined by aCGH.

Glioblastomas (GBM) are rare in children, but reportedly have more varied outcome which suggests differences in tumor etiology compared to typical GBM of adults. To investigate this we performed high resolution array comparative genomic hybridization (aCGH) analysis on three pediatric infratentorial GBM, ages 3.5, 7 and 14 years. Two of these tumors occurred in the brainstem and one in the spinal cord. While histologically typical, one brainstem tumor showed mainly pleomorphic astrocytic cells, whereas the other brainstem and spinal tumors showed a GFAP positive small cell component. Whole chromosomal gains (#1 and #2) and loss (#20) were seen only in the pleomorphic brainstem GBM, which also showed a high level of segmental genomic copy number changes. Segmental loss involving chromosome 8 was seen in all three tumors (Chr8;133039446-136869494, Chr8;pter-3581577, and Chr8;pter-30480019 respectively), whereas loss involving chromosome 16 was seen in only 2 cases with small cell components (Chr16;31827239-qter and Chr16;pter-29754532). Segmental gain of chromosome 7 was shared only between the 2 brainstem cases (Chr7;17187166-qter and Chr7;69824947-qter). Chromosome 17 showed segmental gain of 17q in the backdrop of loss of 17p only in case 1. Segmental gain of chromosome 1q was seen only in case 2. The spinal GBM showed a relatively stable karyotype with a unique loss of Chr19;32848902-qter. None of the frequent losses, gains and amplifications known to occur in adult GBM were identified, suggesting that pediatric infratentorial glioblastomas show a molecular karyotype that was more characteristic of pediatric embryonal tumors than adult GBM.

Leveraging a Clinical Phase Ib Proof-of-Concept Study for the GPR40 Agonist MK-8666 in Patients With Type 2 Diabetes for Model-Informed Phase II Dose Selection.

GPR40 mediates free fatty acid-induced insulin secretion in beta cells. We investigated the safety, pharmacokinetics, and glucose response of MK-8666, a partial GPR40 agonist, after once-daily multiple dosing in type 2 diabetes patients. This double-blind, multisite, parallel-group study randomized 63 patients (placebo, n = 18; 50 mg, n = 9; 150 mg, n = 18; 500 mg, n = 18) for 14-day treatment. The results showed no serious adverse effects or treatment-related hypoglycemia. One patient (150-mg group) showed mild-to-moderate transaminitis at the end of dosing. Median MK-8666 Tmax was 2.0-2.5 h and mean apparent terminal half-life was 22-32 h. On Day 15, MK-8666 reduced fasting plasma glucose by 54.1 mg/dL (500 mg), 36.0 mg/dL (150 mg), and 30.8 mg/dL (50 mg) more than placebo, consistent with translational pharmacokinetic/pharmacodynamic model predictions. Maximal efficacy for longer-term assessment is projected at 500 mg based on exposure-response analysis. In conclusion, MK-8666 was generally well tolerated with robust glucose-lowering efficacy.

Domain organization and oligomerization among H-NS-like nucleoid-associated proteins in bacteria.

The bacterial nucleoid-associated proteins H-NS and StpA can form homomeric or heteromeric complexes, a parallel with protein HU. Thus, functional modulation of H-NS and StpA by one another and by other proteins with appropriate interaction domains is possible. This has implications for bacterial pathogenesis and adaptation to environmental stress.

The solution structure of the domain from MeCP2 that binds to methylated DNA.

MeCP2 is an abundant mammalian protein that binds methylated CpG (mCpG) sequences within double-stranded DNA, represses transcription by recruiting histone deacetylases, and is essential for embryonic development. It is one of a family of proteins which mediate the biological consequences of DNA methylation. These proteins each possess a sequence motif of about 70 residues which, in MeCP2, form a domain necessary and sufficient for binding to mCpG. The solution structure of the mCpG-binding domain (MBD) from MeCP2 has been solved and the DNA-binding surface of the domain mapped using NMR spectroscopy. Residues 95-162 of MeCP2 adopt a novel fold forming a wedge-shaped structure. An N-terminal four-stranded antiparallel beta-sheet forms one face of the wedge, while the other face is formed mainly by a C-terminal helical region. The thin end of the wedge is extended by a long loop between beta-strands B and C containing many basic residues. The B-C loop together with residues in strands B, C and D, and at the N terminus of the alpha-helix, appears to form an interface with methylated DNA. Unstructured residues at the NH2 terminus of the domain are also involved in formation of the complex. The presence of numerous arginine and lysine side-chains on the DNA-binding surface of MBD is consistent with the requirement for the mCpG site to be flanked by non-specific sequences of base-pairs. The absence of symmetry in the domain implies that recognition does not exploit the symmetry of the binding site. A conserved hydrophobic pocket containing the side-chains of Tyr123 and Ile125 on the positively charged beta-sheet face is a candidate for the region of contact with the methyl-groups of the modified cytosine residues.

Urine glucose tests for diabetic patients with impaired vision.

A colorimetric test procedure called Mega-Diastix is described for detection and measurement of glucose in urine. The test is designed for use by diabetic patients with imparied vision. Data establishing the performance capabilities of this rapid, convenient test are presented. As an internal standard, the recommended procedure utilizes effervescent control tablets for preparation of simulated urine. Also described is a touch fermentation test for detection of urinary glucose by totally blind patients. Data are given that demonstrate the accuracy and ease of performance of this test, which entails a rapid yeast fermentation. An internal standard is also incorporated into the procedure for this test.

Dry chemistry: its expanded role in doctor's office testing.

The physician's office laboratory is an important adjunct to quality patient care. Dry chemistry reagents and the instrumentation used with them provide an ideal mechanism to give the patient a timely, relatively inexpensive work-up. An office laboratory can save the physician and his or her staff many frustrations. But unless the physician's office laboratory director makes use of the assistance of laboratorians and manufacturers in setting up good quality assurance systems along with the choice of dry chemistry system, the director may merely replace his or her frustrations with new ones. The limitations of an office laboratory are far outweighed by the benefits in quality patient care.

Urinalysis: its proper role in the physician's office.

Urine study is an important aspect of physician's office laboratories. The contributions that urine study can make are important for both the patient and the physician. State-of-the-art technology makes it possible to have urine test results available at the time the patient is being examined without inconvenience to the patient, the physician, or the laboratory. The cost-containment contributions of urine study are significant for both the patient and the physician. The analytes currently studied provide a broad spectrum of information that relates to many of the problems presented by the typical patient in the typical physician's office.

Analytical applications of immobilized enzymes.

Several clinical laboratory methods using enzymes as reagents now may utilize immobilized enzymes. These are enzymes attached to solid surfaces by adsorption, covalent binding, cross linking or similar means. Immobilized enzymes are widely used presently in convenient tests for urine glucose and galactose or blood glucose and urea, and in serum glucose or urea determinations by automated methods. Advantages include enhanced stability, enzyme conservation, reuse and economy. Limitations in clinical analysis include the requirement for proper handling of both the immobilized enzyme and the specimen with which it is used. Immobilized enzymes of the future should aid in the new discoveries regarding sequential enzyme-catalyzed reactions in living cells and expand the utility of enzymes as reagents in analytical laboratory science.

Health promotion in general practice.

Health promotion is accepted as a desirable and increasingly necessary component of contemporary general practice. Discussion of health promotion in the family medicine setting has neglected to seek the views of General Practitioners. Their contact with patients places them in a unique position to observe the health promotion needs of their patients, and assign priorities to these. A sample of practitioners in the Eastern Sydney Area Health Service was interviewed to ascertain the major areas of preventive medicine needed by their patients. Information was also sought on the General Practitioners' use and views on health promotion services already available in the Eastern Sydney Area Health Service. General Practitioners were receptive to discussion of health promotion and disease prevention activities. Cardiovascular disease was clearly identified as the major area for preventative work for GPs. The large scope for health promotion in general practice ranged from women's health to parent effectiveness training. Although GPs generally viewed favourably the health promotion services provided by the ESAHS limitations on their use were cited.

A randomized, placebo-controlled study of the effects of telcagepant on exercise time in patients with stable angina.

Telcagepant is a calcitonin gene-related peptide (CGRP) receptor antagonist being evaluated for acute migraine treatment. CGRP is a potent vasodilator that is elevated after myocardial infarction, and it delays ischemia during treadmill exercise. We tested the hypothesis that CGRP receptor antagonism does not reduce treadmill exercise time (TET). The effects of supratherapeutic doses of telcagepant on TET were assessed in a double-blind, randomized, placebo-controlled, two-period, crossover study in patients with stable angina and reproducible exercise-induced angina. Patients received telcagepant (600 mg, n = 46; and 900 mg, n = 14) or placebo and performed treadmill exercise at T(max) (2.5 h after the dose). The hypothesis that telcagepant does not reduce TET was supported if the lower bound of the two-sided 90% confidence interval (CI) for the mean treatment difference (telcagepant-placebo) in TET was more than -60 s. There were no significant between-treatment differences in TET (mean treatment difference: -6.90 (90% CI: -17.66, 3.86) seconds), maximum exercise heart rate, or time to 1-mm ST-segment depression using pooled data or with stratification for dose.

Escherichia coli tyrT gene transcription is sensitive to DNA supercoiling in its native chromosomal context: effect of DNA topoisomerase IV overexpression on tyrT promoter function.

We have investigated the in vivo DNA supercoiling sensitivity of the Escherichia coli tRNA(1tyr) gene (tyrT) promoter in its normal chromosomal location. Here, the native tyrT promoter is found to be exquisitely sensitive to mutations and to drugs which alter the level of DNA supercoiling. We show that the response of the tyrT promoter to supercoiling is qualitatively similar to that of a known supercoiling-sensitive tRNA gene promoter, hisR. Specifically, treatments which increase in vivo DNA supercoiling levels enhance transcription of these tRNA genes. Particularly striking is the strong enhancement of expression from both promoters by a transposon insertion mutation in the topA gene encoding DNA toposisomerase I. This phenotypic effect can be complemented by providing active topoisomerase I in trans from a recombinant plasmid. Interestingly, it can also be complemented by overexpression of the genes encoding the subunits of DNA topoisomerase IV. We believe that this is the first demonstration that DNA topoisomerase IV can influence gene expression and it suggests that DNA topoisomerase I is partially redundant, at least in E. coli.

Coupling of Escherichia coli hns mRNA levels to DNA synthesis by autoregulation: implications for growth phase control.

The H-NS protein of enteric bacteria is one of the major proteins of the bacterial nucleoid and seems to play an important role in nucleoid structure. Transcription of the hns gene encoding the H-NS protein appears to be negatively regulated by H-NS itself both in vitro and in vivo. We have examined the role of this mode of regulation in wild-type cells in vivo. We find that hns transcription is down-regulated when DNA synthesis is blocked in growing cells, in a manner that is dependent upon continuing H-NS protein synthesis. These data suggest that hns autoregulation serves to match de novo H-NS synthesis to the demands of DNA synthesis and may maintain a relatively constant H-NS:DNA ratio. It has previously been suggested that hns transcription is activated as cells enter stationary phase, which would require a complete relaxation of autoregulatory control given that DNA synthesis decreases at this time. However, we show here that levels of hns mRNA in fact decline at the onset of stationary phase in a manner fully consistent with the autoregulation model. We also fail to detect any significant accumulation of the H-NS protein in stationary phase.

The Escherichia coli stpA gene is transiently expressed during growth in rich medium and is induced in minimal medium and by stress conditions.

The transcriptional regulation of the stpA gene, encoding the Escherichia coli H-NS-like protein StpA, has been studied as a function of a variety of environmental conditions, and its response to trans-acting factors has been characterized. Chromosomally located stpA is expressed primarily from a promoter immediately upstream of the gene which is severely repressed by the homologous nucleoid-associated protein H-NS. However, we show here that even in a strain containing functional H-NS, stpA is transiently induced during growth of a batch culture in rich medium. It can also be induced strongly by osmotic shock and, to a lesser extent, by an increase in growth temperature. Moreover, when cells are grown in minimal medium, we observe a more sustained induction of stpA which is dependent on the leucine-responsive regulatory protein (Lrp). This enhanced level of stpA transcription is virtually abolished in an H-NS-independent manner when the culture undergoes carbon starvation. A sensitivity of the stpA promoter to DNA topology may contribute to some of these responses. Results reported here show that cloned fragments of the stpA promoter region can confer H-NS and Lrp responsiveness upon a lacZ reporter gene and suggest that several hundred base pairs of DNA upstream of the transcriptional start may be required for regulation by these two proteins.

Self testing, an emerging component of clinical chemistry.

Self testing as a phase of health delivery has been utilized for approximately 70 years, but within the last two decades there has been an increasing interest in and use of self testing. The practice of self testing has a sound basis, which involves medical relevancy, cost containment, and convenience. It is reasonable to anticipate that self testing will increase in the future as medical needs and available procedures are established. The clinical chemist, the physician, and the industrial producer of test systems all have important roles in self testing. The clinical chemist, whether in a hospital laboratory or in an industrial setting, has the responsibility to create new self-testing procedures that represent expansion and improvement over those currently available. The clinical chemist also has a critical role in the evaluation of new self-testing procedures and in validating their capability of providing high-quality information. The provision of quality-assurance programs and proficiency programs for the user can most effectively be carried out by clinical chemists. The clinical chemist can also play an important role as a consultant, teacher/educator, and trouble shooter in recognizing and helping solve problems that may appear in various areas of self testing. The classic role of the physician has been to diagnose disorders of the patients and provide therapy for effective care. The role of the physician in self testing is quite comparable to his usual role, since the ultimate diagnosis of disease will be carried out by the physician and he will continue to be the source for definition of therapy. A major portion of self testing will be carried out with the recommendation of a physician, and he will maintain a role in the interpretation of results. The physician needs to be familiar with self-testing practices and procedures and be prepared to provide interpretation of self-testing results. Industry supplies an increasing proportion of reagent systems and instruments for the clinical laboratory. The supplying of reagent systems and small instruments for self testing is almost completely a role of industry. The creation and funding of new products for self testing will be provided by industry to a large extent. A critical function of industry is to provide high-quality products and efficient customer service to the self-testing component of health delivery. We have each played a role in self testing over a period of approximately 40 years. During this period self testing has become an important phase of clinical laboratory practice.(ABSTRACT TRUNCATED AT 400 WORDS)

A role for the Escherichia coli H-NS-like protein StpA in OmpF porin expression through modulation of micF RNA stability.

When a wild-type strain of Escherichia coli and its stpA, hns and stpA hns mutant derivatives were compared by two-dimensional protein gel electrophoresis, the levels of expression of several proteins were found to vary. One of these was identified as the outer membrane porin protein, OmpF. In the stpA hns double mutant, the level of OmpF was downregulated dramatically, whereas in hns or stpA single mutants, it was affected only slightly. Transcription from the ompF promoter was reduced by 64% in the double mutant; however, the level of ompF mRNA was reduced by 96%. This post-transcriptional expression was found to result from a strong reduction in the half-life of ompF message in the double mutant. The micF antisense RNA was shown to be involved in OmpF regulation by StpA using a strain deleted for micF. Moreover, micF antisense RNA accumulated considerably in an stpA hns background. Transcriptional data from a micF-lacZ fusion and measurements of micF RNA half-life confirmed that this was caused by transcriptional derepression of micF as a result of the hns lesion and increased micF RNA stability due to the absence of StpA (a known RNA chaperone). These data suggest a novel facet to the regulation of OmpF expression, namely destabilization of micF RNA by StpA.

The StpA protein functions as a molecular adapter to mediate repression of the bgl operon by truncated H-NS in Escherichia coli.

The mechanism of repression of the beta-glucoside utilization (bgl) operon of Escherichia coli by a carboxy-terminally truncated derivative of the nucleoid-associated protein H-NS which is defective in DNA binding was investigated. The DNA-binding function of the H-NS-like protein StpA was found to be necessary for repression, which is consistent with a role for StpA as a DNA-binding adapter for mutant derivatives of H-NS.

Cholecalciferol 25-hydroxylation is similar in liver microsomes from male and female rats when cholecalciferol concentration is low.

We compared cholecalciferol 25-hydroxylation in liver microsomes of male and female rats. The rate of production of 25-hydroxycholecalciferol was similar in liver microsomes from female rats and those from male rats when cholecalciferol concentration ranged from 50 to 200 nmol/L. The liver cytosolic fraction stimulated the 25-hydroxylase activity of the microsomes up to 100% in both male and female rats at 44 nmol/L cholecalciferol. Cytosol metabolized cholecalciferol to a currently unidentified metabolite. At 300 nmol/L cholecalciferol, synthesis of the cytosolic metabolite was 100% greater than at 100 nmol/L and coincided with 32% lower synthesis of 25-hydroxycholecalciferol. These results suggest similar 25-hydroxy-lase activity in liver microsomes from male and female rats and similar ability of liver cytosol from these rats to stimulate 25-hydroxylation at low nanomolar concentrations of cholecalciferol, whereas inhibitory effects of cytosol at higher concentrations of cholecalciferol were shown.