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End of 21st‐century hydroclimate projections suggest an expansion of subtropical dry zones, with Mediterranean and Sahel regions becoming much drier. However, paleobotanical assemblage evidence from the middle Miocene (17‐12 Ma), suggests both regions were instead humid environments. Here we show that by modifying regional sea surface temperatures (SST) in an Earth System Model (CESM1.2) simulation of the middle Miocene, the increased ocean evaporation and integrated water vapor flux overrides any drying effects associated with warming‐induced land‐surface evaporation driven by atmospheric CO2 concentrations. These modifications markedly reduce the bias in the model‐data comparison for this period. A vegetation model (BIOME4) forced with simulated climatologies predicts both regions were dominated by mixed forest, which is largely consistent with the paleobotanical record. This study unveils the potential for wetter subtropical Mediterranean climates associated with warming, presenting an alternative scenario from future drying projections with localized SST warming governing regional climate change. Plain Language Summary: Climate models project drier conditions over Europe and Northern Africa due to global warming. However, evidence from a past warm climate period, the middle Miocene (∼15 million years ago), finds wetter rather than drier environments. We refine climate model boundary conditions by reconstructing warmer ocean waters in the North Atlantic based on proxy evidence. The warmer ocean produces wetter environments by enhancing North Atlantic precipitation events and the North African monsoon. The increased rainfall and surface temperature cause a vegetation model to predict more forest coverage over Europe and Northern Africa, which is consistent with fossil evidence from ∼15 million years ago. This study unveils the potential for wetter climates associated with warming, presenting an alternative scenario from future drying projections, with localized sea surface warming governing regional climate. Key Points: Middle Miocene Europe rainfall discrepancy between herpetological (dry) and paleobotanical (wet) records complicate climate model validationSimulations that produce dry environments also produce cool North Atlantic sea surface temperatures which are inconsistent with proxiesSSTs informed by North Atlantic proxies produce wetter environments consistent with paleobotanical evidence [ABSTRACT FROM AUTHOR]

Neogene sediments in the UK are ideally situated for understanding the early development of hydrological dynamics and atmospheric circulation that led to the modern oceanic climate of northwest Europe. Onshore Neogene fossiliferous deposits in the UK are limited to the solution pipe fills at Trwyn y Parc in Anglesey (Middle Miocene), the Brassington Formation of Derbyshire (Serravallian‐Tortonian), and the Coralline Crag Formation (latest Zanclean‐earliest Piacenzian) and Red Crag Formation (Piacenzian‐Gelasian) in southeast England. Palynoflora from these localities can be used to provide snapshots into the climate at the time of deposition, however, palaeobotanical‐based reconstructions are typically lacking in their poor estimation of error. Therefore, we present the first pre‐Quaternary application of two terrestrial climate reconstruction techniques: CREST (Climate Reconstruction SofTware) and CRACLE (Climate Reconstruction Analysis using Coexistence Likelihood Estimation), that use Bayesian and likelihood estimation probability respectively to generate a new palaeoclimate reconstruction, and compare this to Co‐existence Approach reconstructions from the UK and continental Europe. Our study shows how Mean Annual Temperature (MAT) declines by 3°–6°C, Mean Annual Precipitation (MAP) declines by 480–600 mm and Precipitation Seasonality approximately halves throughout the Neogene. CREST and CRACLE reconstructions overlap with the Co‐exisence Approach and have the advantage of providing uncertainty, rather than ranges. The UK appears to have had a milder, wetter, and less seasonal climate than continental Europe. This is likely due to the buffering effects of the Atlantic Ocean and North Sea ameliorating the UK Neogene climate despite regional and global changes in atmospheric and oceanic circulation. Key Points: A new probability‐based terrestrial Neogene climate reconstruction for the UKReconstructions are in line with previous terrestrial reconstructions and independent proxy reconstructions from the wider regionMiocene and Pliocene reconstructions align with predictions for future anthropogenic warming by 2100 [ABSTRACT FROM AUTHOR]

Background: Pathologists sometimes disagree over the histopathologic diagnosis of melanoma. 'Over‐calling' and 'under‐calling' of melanoma may harm individuals and healthcare systems. Objectives: To estimate the extent of 'over‐calling' and 'under‐calling' of melanoma for a population undergoing one excision per person and to model the impact of potential solutions. Methods: In this epidemiological modelling study, we undertook simulations using published data on the prevalence and diagnostic accuracy of melanocytic histopathology in the U.S. population. We simulated results for 10 000 patients each undergoing excision of one melanocytic lesion, interpreted by one community pathologist. We repeated the simulation using a hypothetical intervention that improves diagnostic agreement between community pathologist and a specialist dermatopathologist. We then evaluated four scenarios for how melanocytic lesions judged to be neither clearly benign (post‐test probability of melanoma < 5%), nor clearly malignant (post‐test probability of melanoma > 90%) might be handled, before sending for expert dermatopathologist review to decide the final diagnosis. These were (1) no intervention before expert review, (2) formal second community pathologist review, (3) intervention to increase diagnostic agreement and (4) both the intervention and formal second community pathologist review. The main outcomes were the probability of 'over‐calling' and 'under‐calling' melanoma, and number of lesions requiring expert referral for each scenario. Results: For 10 000 individuals undergoing excision of one melanocytic lesion, interpreted by a community pathologist, a hypothetical intervention to improve histopathology agreement reduced the number of benign lesions 'over‐called' as melanoma from 308 to 164 and the number of melanomas 'under‐called' from 289 to 240. If all uncertain diagnoses were sent for expert review, the number of referrals would decrease from 1500 to 737 cases if formal second community pathologist review was used, and to 701 cases if the hypothetical intervention was additionally used. Conclusions: Interventions to improve histopathology agreement may reduce melanoma 'over‐calling' and 'under‐calling'. [ABSTRACT FROM AUTHOR]

The study investigated the impact of feeding OmniGen‐AF® (OG; Phibro Animal Health, Quincy, IL) from dry‐off to week 4 of lactation at two doses on production performance and metabolic adaptation of multiparous Holstein cows. Forty‐eight cows were blocked and assigned randomly to three treatments: OG was fed at 0 g/head/day (CON), 60 g/head/day (OG60), or 90 g/head/day (OG90). No difference was observed in dry matter intake (DMI) throughout the experiment, whereas feeding OG tended to decrease the percentage body weight change (PWC) on week 2. Although colostrum yield was not affected by treatment, colostrum IgG production of OG90 tended to be higher than that of CON. OG supplementation did not affect overall milking performance but decreased milk SCC during the first 4 weeks of lactation. In prepartum, OG supplementation decreased the concentrations of serum albumin and calcium, and increased serum globulin. OG supplementation tended to increase serum total protein, globulin, and calcium contents postpartum. Furthermore, reduced incidence of mastitis and udder edema were observed. In conclusion, supplementing cows with OG from dry‐off period reduces or modulates the inflammation responses associated with parturition, potentially resulting in improved postpartum health, while feeding OG more than 60 g/head/day did not warrant further benefits. [ABSTRACT FROM AUTHOR]

Residential air exchange rates ( AERs) are vital in understanding the temporal and spatial drivers of indoor air quality ( IAQ). Several methods to quantify AERs have been used in IAQ research, often with the assumption that the home is a single, well-mixed air zone. Since 2005, Health Canada has conducted IAQ studies across Canada in which AERs were measured using the perfluorocarbon tracer ( PFT) gas method. Emitters and detectors of a single PFT gas were placed on the main floor to estimate a single-zone AER ( AER1z). In three of these studies, a second set of emitters and detectors were deployed in the basement or second floor in approximately 10% of homes for a two-zone AER estimate ( AER2z). In total, 287 daily pairs of AER2z and AER1z estimates were made from 35 homes across three cities. In 87% of the cases, AER2z was higher than AER1z. Overall, the AER1z estimates underestimated AER2z by approximately 16% ( IQR: 5-32%). This underestimate occurred in all cities and seasons and varied in magnitude seasonally, between homes, and daily, indicating that when measuring residential air exchange using a single PFT gas, the assumption of a single well-mixed air zone very likely results in an under prediction of the AER. [ABSTRACT FROM AUTHOR]

Indoor fine particles ( FPs) are a combination of ambient particles that have infiltrated indoors, and particles that have been generated indoors from activities such as cooking. The objective of this paper was to estimate the infiltration factor ( Finf) and the ambient/non-ambient components of indoor FPs. To do this, continuous measurements were collected indoors and outdoors for seven consecutive days in 50 non-smoking homes in Halifax, Nova Scotia in both summer and winter using DustTrak ( TSI Inc) photometers. Additionally, indoor and outdoor gravimetric measurements were made for each 24-h period in each home, using Harvard impactors ( HI). A computerized algorithm was developed to remove (censor) peaks due to indoor sources. The censored indoor/outdoor ratio was then used to estimate daily Finfs and to determine the ambient and non-ambient components of total indoor concentrations. Finf estimates in Halifax (daily summer median = 0.80; daily winter median = 0.55) were higher than have been reported in other parts of Canada. In both winter and summer, the majority of FP was of ambient origin (daily winter median = 59%; daily summer median = 84%). Predictors of the non-ambient component included various cooking variables, combustion sources, relative humidity, and factors influencing ventilation. This work highlights the fact that regional factors can influence the contribution of ambient particles to indoor residential concentrations. [ABSTRACT FROM AUTHOR]

Background and Objective Dentin sialophosphoprotein ( DSPP) and its cleaved products, dentin phosphoprotein ( DPP) and dentin sialoprotein ( DSP), play important roles in biomineralization. Recently, we observed that DSPP is highly expressed in the alveolar bone and cementum, indicating that this molecule may play an important role in the formation and maintenance of a healthy periodontium, and its deletion may cause increased susceptibility to periodontal diseases. The objective of this investigation was to study the effects of Dspp ablation on periodontal tissues by analyzing Dspp null mice. Material and Methods Newborn to 6-mo-old Dspp null mice were examined, and the 3- and 6-mo-old Dspp null mice were characterized in detail using X-ray radiography, histology and scanning electron microscopy (backscattered as well as resin-infiltrating). Wild-type mice of the same age groups served as the normal controls. Results The Dspp null mice showed significant loss of alveolar bone and cementum, particularly in the furcation and interproximal regions of the molars. The alveolar bone appeared porous while the quantity of cementum was reduced in the apical region. The canalicular systems and osteocytes in the alveolar bone were abnormal, with reduced numbers of canaliculi and altered osteocyte morphology. The loss of alveolar bone and cementum along with the detachment of the periodontal ligaments ( PDL) led to the apical migration of the epithelial attachment and formation of periodontal pockets. Conclusion Inactivation of DSPP leads to the loss of alveolar bone and cementum and increased susceptibility to bacterial infections in PDL of Dspp null mice. The fact that the loss of DSPP results in periodontal diseases indicates that this molecule plays a vital role in maintaining the health of the periodontium. [ABSTRACT FROM AUTHOR]

As part of the road widening scheme between London and Dover, Oxford Archaeology South uncovered a large boundary ditch of Iron Age origin that contained Iron Age and Roman inhumations, adjacent to which was a small mid-late Roman cemetery, interpreted as a rural cemetery for Romano-British farmers. Grave goods in the cemetery were restricted to a few individuals with hobnailed boots. Bulk bone collagen isotopic analysis of 11 skeletons of Iron Age and Roman date gave a typical C3 terrestrial signal (average δ13C = −19.8‰, δ15N = 9.3‰), but also revealed one (SK12671) with a diet which included a substantial C4 component (δ13C = −15.2‰, δ15N = 11.2‰). This is only the second such diet reported in Roman Britain. Subsequent δ18Oc and 87Sr/86Sr measurements on the dental enamel in this individual were, however, consistent with a 'local' origin, indicating that either C4 protein was consumed in Late Roman Britain, or that he came from somewhere else, but where conditions gave rise to similar isotopic values. If we accept the latter, then it indicates that using oxygen and strontium isotopes alone to identify 'incomers' may be problematic. The provision of hobnailed boots for the dead appears to have had a strong symbolic element in Late Roman Britain. We suggest that in this case the boots may be significant, in that he was being equipped for the long march home. Am J Phys Anthropol, 2011. © 2011 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The article describes the design and application of a light-weight uniaxial tensile stage (TS) for micro-X-ray diffraction experiments at essential loading scenarios found in conventional engineering stress-strain tests. One of the key features implemented as part of the design is the highly portable system to allow ease of transport to and from synchrotron and/or laboratory facilities. The authors performed experiments to highlight the instrumentation capabilities of the TS for direct measurement of deviatoric strain.

Apatite (U–Th)/He and fission track thermochronometry have been combined with 3D thermal modelling to constrain the late- to post-orogenic exhumation history of the Central Pyrenees, Spain. Data from four massifs immediately north and south of the present drainage divide of the mountain belt reveal a diachroneity in the transition from syn- to post-orogenic forcing of exhumation. Immediately south of the drainage divide, rapid exhumation of ∼1.5 mm year−1 decelerated after ∼30 Ma to ∼0.03 mm year−1. A similar transition occurred immediately north of the drainage divide at the same time. Further south, in the core of the Axial Zone antiformal stack of the Pyrenees, rapid (∼1 mm year−1), syn-orogenic exhumation continued to ∼20 Ma, but slowed to ∼0.1–0.2 mm year−1 soon after that time. This order of magnitude decrease in exhumation rates across the orogen records the diachronous transition into a post-orogenic state for the mountain belt. These data do not record rejuvenation of exhumation in Late Miocene or Pliocene times driven either by large-scale base-level change or an evolution to more erosive climatic conditions. [ABSTRACT FROM AUTHOR]

Epidermolysis bullosa (EB) is a rare inherited blistering disease, with an incidence of 19.6 cases per million live births. GLO:3NZ/01jul20:jdv16301-fig-0001.jpg PHOTO (COLOR): Clinical photographs taken before and after oral dapsone therapy were given to each patient. Dapsone may be a valuable and untapped adjunct therapy for patients with this devastating disease. [Extracted from the article]

Students of public policy have recognized that not all policies are completely or mostly shaped by socioeconomic factors. Some policies, known as morality policies, derive from the deeply held values and beliefs of effective participants in the policy-making process. To better understand this distinct policy category and where it exists, policy analysts must test for the impact of both socioeconomic forces and explanatory factors developed in morality politics theory (particularly religious contexts). This study attempts to explain differences in state science education standards with regard to stipulated instruction in evolutionary theory as morality policy.A cross-sectional study of the American states employing ordinary least squares and logistic regression analysis assesses the impact of popular evangelical adherence over the presence of evolution-friendly state science standards, ceteris paribus.Socioeconomic factors inadequately explain the variation in state science standards. Furthermore, these standards are morality policies with clearly defined religious implications and are better explained by state religious divisions than by other cultural forces such as state ideological context.This study demonstrates that some policies have clear implications for religious beliefs and may represent a subcategory of morality policy. These kinds of policies are better explained by religious contexts than other political and cultural determinants of morality policies. [ABSTRACT FROM AUTHOR]

The present article analyzes signaling by elected officials of moderate or centrist legislative behavior from a benefits/costs perspective. To do so, we provide statistical evidence regarding the tendency of senators to join the U.S. Senate Centrist Coalition, a congressional membership organization of moderate legislators. We find that changes in party loyalty, perhaps due to changes in constituent preferences, and U.S. Senate tenure are both important determinants of membership in the Centrist Coalition. Tests also point out that freshman senators are more likely than more senior senators to seek membership as a form of information provision. [ABSTRACT FROM AUTHOR]

AbstractAimThe objective of this study was to audit the quality of root canal treatment performed by undergraduate students on adult patients. MethodologyAll root canal treatment completed by first and second clinical year undergraduates over a 12-month period were included in the study. The availability and readability of pretreatment, diagnostic length, try-in point and postoperative radiographs were noted for each case. All readable postoperative radiographs of primary treatments were examined for quality of the root filling, categorized as complete, incomplete apical, incomplete apical and lateral or not assessable. The distance from the radiographic apex of the root to the apical extent of each root filling was measured to 0.1 mm precision. ResultsUndergraduates performed primary treatment on 157 teeth. A postoperative radiograph was available in 97% of cases. A try-in point radiograph was unavailable in one-fifth of cases. Twenty-seven teeth (13%) were categorized as satisfactory in terms of both radiographic quality and distance of the root filling from the radiographic apex. ConclusionsOverall, the technical quality of root canal treatment completed by undergraduate students was poor. [ABSTRACT FROM AUTHOR]

Background The industrial processing of scampi (Nephrops norvegicus) generates bioaerosols which can cause occupational respiratory disease in exposed individuals. The objective of this study was to develop a monoclonal antibody-based immunoassay to measure scampi proteins collected using standard personal air sampling methods. Methods A monoclonal antibody was generated which predominantly bound to a single 97 Kd scampi protein, which we have shown to be a major allergen. This protein was shown by SDS PAGE immunoblotting to be present in various aqueous extracts from wastes produced during scampi processing. A quantitative immunoslotblot method was developed to quantify scampi from air sample filters. Results We demonstrated the utility of this method by showing a significant difference (P = 0.015) in the level of exposure of two groups of 12 workers processing scampi at a traditional open workstation (GM = 607 ng m-3) and at an enclosed workstation (GM = 451 ng m-3). Conclusion We conclude that this assay can be used, in conjunction with health surveillance, to monitor exposure and the efficacy of measures to reduce exposure to airborne scampi allergen in an occupational environment. [ABSTRACT FROM AUTHOR]

Abstract Ultrastructural studies have established that gonadotropin releasing hormone (GnRH) neuronal cell bodies receive sparse synaptic input compared to other neuronal cell types. In the present studies, immunocytochemistry for the presynaptic marker synaptophysin, coupled with confocal microscopy, was employed to evaluate whether there was a difference in synaptic input to GnRH cells within preoptic area grafts (hypogonadal, HPG; preoptic area, POA) in hypogonadal female mice that did or did not show ovarian development. GnRH cells in HPG/POA mice with ovarian development exhibited significantly higher numbers of synaptophysin immunoreactive (syn-IR) appositions as compared with HPG/POA mice without ovarian development. This suggests that synaptic input to the grafted GnRH cells is important for the correction of reproductive functions in HPG/POA mice. Following mating, Fos immunoreactivity was present in several GnRH cells in HPG mice with successful POA grafts, indicating the establishment of neuronal projections conveying somatosensory information to the GnRH cells in these mice. The presence of a higher number of syn-IR appositions to GnRH cells in the successful grafts supports this hypothesis. [ABSTRACT FROM AUTHOR]

Abstract LANDSAT Multi-Spectral Scanner imagery was used to determine aspects of the fire regimes of Kakadu National Park (in the wet–dry tropics of Australia) for the period 1980–1995. Three landscape types recognized in this Park were Plateau, Lowlands and Floodplain. Areas burned in early and late dry seasons each year were documented using a Geographical Information System. Regression analyses were used to examine time trends in the areas burned each year and the interrelationships between early and late dry season burning. The proportions of landscapes having different stand ages (years since fire), and the proportions having had different fire intervals, were compared with results expected from the simplest random model (i.e. one in which the probability of ignition at a point [PIP] burning annually was constant). Using overlays of successive stand-age maps, PIP could be calculated as a function of stand age. The Lowlands burned extensively each year; the areas burned by late dry season fires adding to those burned in the early dry season such that around 50–60% of the total area burned annually. Early dry season fires have lower intensities than late dry season fires, on average. Using a theoretically constant PIP and the mean proportion burned per year as the only input, predictions of areas burned as a function of stand age and fire interval were reasonable when compared with the empirical data, but best for the Lowlands landscape. PIP functions for Lowlands and Floodplains had negative slopes, an unexpected result. The nature of these PIP functions may reflect heterogeneity in fire proneness of the various vegetation types within landscapes. The scale of measurement, the scale of variation in vegetation types within a landscape, and the accuracy of the determination of burned areas, are constraints on the accuracy of fire-interval and seasonality determination perceived from an analysis of satellite data. [ABSTRACT FROM AUTHOR]

Editorial. Introduces a series of articles that are related to diabetic medicine, published in the May 2000 issue of the `Diabetic Medicine' journal.

A redox dye, methylene blue, was compared with subgingival root surface debridement and sterile water in the treatment of adult periodontitis. Plaque and gingival indices, bleeding on probing, and microbiological samples were obtained at baseline, and at 1, 4, 8 and 12 weeks following treatment. All subjects had matched pockets in each of the 4 quadrants, of 5 mm or more. One treatment consisted of 0.1% methylene blue gel irrigated professionally at 0, 1 and 4 weeks, and by subjects at days in between up to 4 weeks, at chosen sites within a randomly selected quadrant (split-mouth design). A 2nd treatment was sterile water irrigation as above. A 3rd quadrant received subgingival debridement, and sites in the 4th received methylene blue incorporated into a slow-release device of a biodegradable collagen alginate vicryl composite. All sites showed improvements in clinical and microbiological parameters. However, no statistically significant differences between treatment types were found for clinical measurements. Although plaque index tended to increase after week 1, gingival index was reduced, as was the papilla bleeding index. Probing depth reductions were approximately 1.2 mm for all treatments. Microbiological variables showed an increase in cocci and a decrease in motile organisms for all groups, the latter reaching statistical significance for subgingival debridement. The reductions in spirochaetes were significant for subgingival debridement and methylene blue by slow-release. Culture demonstrated an increase in the aerobe:anaerobe ratio for all groups, which was statistically significant initially (weeks 1 and 4) for subgingival debridement. Methylene blue was also effective statistically in improving this ratio, both by irrigation and slow-release (week 4). Methylene blue also significantly reduced the numbers of black-pigmented anaerobes during the trial period, both by irrigation and slow-release, which sterile water and subgingival debridement failed to do. No serious adverse experiences were seen, however, significantly greater morbidity was associated with subgingival debridement. These results clearly demonstrate that in altering the microflora to one that is more compatible with periodontal health, methylene blue treatment is comparable, or even better, than the currently standard treatment of subgingival debridement, and is better tolerated. [ABSTRACT FROM AUTHOR]

A blind, two-way, crossover clinical trial, completed by 44 adult subjects, instructed in specific oral hygiene techniques, was carried out to compare the effectiveness of plaque removal between a new Scandinavian double-headed toothbrush and a popular single-headed brush, each used for one week. The results showed that the double-headed brush was significantly more effective in removing plaque overall than a conventional brush. The effect was most evident on all lingual surfaces, especially in the lower arch and molar regions. It was also particularly pronounced when the double-headed toothbrush was allocated for use in the 2nd week of the study. There was no significant difference in the cleaning ability of the 2 brushes on the buccal surfaces of the teeth. [ABSTRACT FROM AUTHOR]

The chemical mutagen ethylmethanesulphonate (EMS) has been used to generate mutants of Erwinia carotovora subspecies carotovora which are defective in the secretion of pectinases (Pel) and cellulases (Cel) but unaltered for protease (Prt) secretion. Such mutants, called Out-, still synthesize Pel and Cel but these enzymes accumulate within the periplasm. Cosmid clones carrying wild-type E. carotovora ssp. carotovora DNA, identified by their ability to restore the Out+ phenotype when transferred to some Out- mutants, were classified into six complementation groups using cosmids and cosmid derivatives. Analysis of the nucleotide sequence of a 12.7kb DNA fragment, encompassing complementing cosmid inserts, revealed a coding capacity for 13 potential open reading frames (ORFs), and these were designated outC-outO. Some of the out gene products were visualized using a T7 gene 10 expression system. The predicted Out proteins are highly similar to components of extracellular enzyme secretion systems from a diverse range of eubacteria including Erwinia chrysanthemi, Klebsiella oxytoca, Aeromonas hydrophila, Pseudomonas aeruginosa and Xanthomonas campestris. Lower levels of similarity exist between Ecc Out proteins and components of macromolecular trafficking systems from Bacillus subtilis, Haemophilus influenzae, Agrobacterium tumefaciens, Yersinia pestis and a protein involved in the morphogenesis of filamentous bacteriophages such as M13. [ABSTRACT FROM AUTHOR]

The CorA Mg2+ transport system of Salmonella typhimurium mediates both influx and efflux of Mg2+. Mutations at the corA locus (83.5min) confer resistance to Co2+. Using transposon mutagenesis, three additional Co2+ resistance loci (corB, corC, and cord) were found and mapped to 55, 15, and 3 min, respectively, on the S. typhimurium chromosome. No mutations corresponding to the reported corB locus at 95 min in Escherichia coli were obtained. The corB, corC, and corD mutations confer levels of Co2+. resistance intermediate between those of the wild-type and corA mutations. Isogenic straits were constructed containing combinations of transposon insertion mutations in each of the three Co2+-resistance loci to assess their influence on the CorA Mg2+ transport system. The Vmax and Km values for 28Mg2+ or for 57Co2+ and 63Ni2+ influx, analogues of Mg2+ transported by the CorA system, were changed less than twofold compared with the wild-type values, regardless of the mutation(s) present. However, while efflux of 28Mg2+ through the CorA system was decreased threefold in strains carrying one or two mutant alleles among corB, corC, or corD, efflux was completely abolished in either a corA or a corBCD strain. Thus, although the corA gene product is necessary and sufficient to mediate Mg2+ influx, Mg2+ efflux requires the presence of a wild-type allele of at least one of the corB, corC or ... [ABSTRACT FROM AUTHOR]

The dipeptide permease (Dpp) is one of three genetically distinct peptide-transport systems in enteric bacteria. Dpp also plays a role in chemotaxis towards peptides. We have devised three selections for dpp mutations based on resistance to toxic peptides (bacilysin, valine-containing peptides, and bialaphos). All dpp mutations mapped to a single chromosomal locus between 77 and 78 min in Salmonella typhimurium and at 79.2 min in Escherichia coli. Expression of dpp was constitutive in both species but the absolute level of expression varied widely between strains. At least in part this difference in expression levels is determined by cis-acting sequences. The dpp locus of E. coli was cloned. The first gene in the operon, dppA, encodes a periplasmic dipeptide-binding protein (DBP) required for dipeptide transport and chemotaxis. Downstream of dppA are other genes required for transport but not for chemotaxis. The dipeptide-binding protein was found to share 26.5% sequence identity with the periplasmic oligopeptide-binding protein OppA. [ABSTRACT FROM AUTHOR]

The broad spectrum protease inhibitor, α2--macgrolobulin (α2M) . is one of the host's principal regulators of both endogenous and exogenous proteases and is likely to have an important role in the regulation of proteolytic activity at inflammatory sites. We have determined the amount of complexed (comα2M) and total α2M (totα2M) in gingival crevicular fluid (GCF) harvested from shallow and deep sites in adult periodontitis (AP) patients (n=21). An ELISA technique was developed to measure both forms of α,M in the same sample utilizing a monoclonal antibody (MAb) specific for the complexed form. In addition, pro- tease activity towards human serum albumin (Prot1), transferrin (Prot2) and Nα-benzoyl-L-arginine 7-amido-4-methylcoumarin-hydrochloride (BAAMc; Prot3) were determined in a second GCF sample from the same site. Plasma α2M concentrations were only positively correlated (p=0.0163) with GCF totα2M from highly inflamed sites. We observed a significant positive correlation between totaα2M and proteolytic activity in GCF from deep sites but not from shallow sites (Prot1: p=0.002: Prot2: p=0.005). A similar correlation between totα2M and proteolytic activity was found at highly inflamed sites (Prot1: p= 0.014: Prot2: p=0.002). A very high proportion of the totα2M in GCF was in the complexed form at both shallow (71.14%14;±29.13) and deep sites (68.17%± 28.5) Coniα2M was positively correlated with proteolytic activity only in deep sites (Prot1: p=0.015; Prot2: p=0.031). Our results suggest that the concentration of totα2M in the gingival crevice is positively associated with the amount of proteolvtie activity at the site and that protease activities in GCF may only partly explain the high percentage conversion α2M to the complexed form. The high level of α2M inactivation in GCF from AP patients reported here may have significance not only in view of its role as a broad spectrum protease inhibitor hut also through the differential effects of native vs complexed α2M on the regulation of immune responses. [ABSTRACT FROM AUTHOR]

A small-scale clinical trial was carried out to evaluate the effect of a redox agent, methylene blue. on microbiological and clinical indices of chronic periodontitis. Methylene blue was applied subgingivally on a daily basis for 7 d to 25 test sites in 7 patients and the sites evaluated clinically and microbiologically for up to 14 d: 25 control sites in the same patients received sterile water. The test sites showed statistically significant differences from the control sites in terms of changes in a number of clinical and microbiological indices. In the test sites the proportions of anaerobes. Gram-negative anaerobes, spirochetes and motile bacteria decreased, as did the crevicular fluid flow, while the proportions of facultative anaerobes and cocci increased. These changes are indicative of a shift towards periodontal health. No significant differences were observed between the test and control sites in terms of bleeding on probing or pocket depth. The encouraging results of this preliminary study suggest that the use of redox agents in the treatment of chronic periodontitis warrants further investigation. [ABSTRACT FROM AUTHOR]

The provision of the wide variety of support services necessary for patients with multiple handicaps is often poorly coordinated. In this study a group of 108 adults, aged from 19 to 90 years, who suffered from multiple physical handicaps and attended a rehabilitation day care centre, had their visual functions and requirements assessed by a multidisciplinary team. The programme consisted of five stages. Each patient was initially screened and subsequently referred for more detailed optometric, ophthalmological, low vision or rehabilitation assessments, where appropriate. Results indicated that many of the patients had not been receiving regular ocular assessments and would benefit from the provision of an optical appliance or ophthalmological treatment. The survey provided staff at the rehabilitation centre with information on the visual status of individual patients and enhanced general eye-care awareness. [ABSTRACT FROM AUTHOR]

The authors comment on the belief that low-gradient surfaces preserved at high elevations in parts of the Pyrenees record an altiplanation surface that depicted the mountain belt during Late Miocene times. According to them, they do not doubt the possibility of a Pliocene resurrection of the central Pyrenees. However, they added that as the supporting data are inadequate and the U-Th/He thermochronology gives no evidence to support the theory, they remained agnostic.