ß-Cell and renal transplantation options for diabetes.

Despite major advances in structured education, insulin delivery and glucose monitoring, diabetes self-management remains an unremitting challenge. Insulin therapy is inextricably linked to risk of dangerous hypoglycaemia and sustained hyperglycaemia remains a leading cause of renal failure. This review sets out to demystify transplantation for diabetes multidisciplinary teams, facilitating consideration and incorporation within holistic overall person-centred management. Deceased and living donor kidney, whole pancreas and isolated islet transplant procedures, indications and potential benefits are described, in addition to outcomes within the integrated UK transplant programme.

Aerobic method for the synthesis of nearly size-monodisperse bismuth nanoparticles from a redox non-innocent precursor.

Herein, we report an aerobic synthesis method to produce bismuth nanoparticles (Bi NPs) with average diameters in the range 40-80 nm using commercially available bismuth triiodide (BiI3) as the starting material; the method uses only readily available chemicals and conventional laboratory equipment. Furthermore, size data from replicates of the synthesis under standard reaction conditions indicate that this method is highly reproducible in achieving Bi NP populations with low standard deviations in the mean diameters. We also investigated the mechanism of the reaction, which we determined results from the reduction of a soluble alkylammonium iodobismuthate precursor species formed in situ. Under appropriate concentration conditions of iodobismuthate anion, we demonstrate that burst nucleation of Bi NPs results from reduction of Bi3+ by the coordinated, redox non-innocent iodide ligands when a threshold temperature is exceeded. Finally, we demonstrate phase transfer and silica coating of the Bi NPs, which results in stable aqueous colloids with retention of size, morphology, and colloidal stability. The resultant, high atomic number, hydrophilic Bi NPs prepared using this synthesis method have potential for application in emerging x-ray contrast and x-ray therapeutic applications.

Vermetid gastropods modify physical and chemical conditions above coral-algal interactions.

Interaction modifications can arise when a third species alters the physical and chemical environment within which two other species interact. On coral reefs, corals and algae commonly interact amid a suite of other species that may modify their interaction. Massive Porites coral and algal turfs often are covered by mucus nets cast by the vermetid gastropod, Ceraesignum maximum. Previously, vermetid mucus nets have been shown to have deleterious effects on corals. Here, we hypothesized that vermetids not only have direct effects on coral, but they also change the local physical and chemical environment establishing the potential for interaction modifications by intensifying the effects of algae on corals. To test this, we examined the effect of vermetids on physical and chemical aspects of the environments. We quantified light penetration, water flow, diffusive boundary layer (DBL) thickness, and oxygen concentrations in the presence and absence of vermetid nets. Vermetid nets did not affect light levels. Because we observed reduced water flow and increased DBL thickness in the presence of nets, we also expected to observe high oxygen concentration over coral surfaces. Instead, we observed no difference in oxygen concentrations in the presence of mucus nets. To explain the lower than expected oxygen concentrations, we hypothesize that nets decreased photosynthesis and/or increased respiration of corals and algae and their associated microbiota. This is the first study to explore mechanisms underlying the deleterious effects of vermetids on corals, and shows that vermetid mucus nets may modify coral-algal interactions by intensifying physical and chemical conditions.

Clinical, haematological, cytokine and acute phase protein changes during experimental Babesia gibsoni infection of beagle puppies.

Babesia gibsoni is a haemoprotozoan parasite of emerging global importance. The clinical presentation of babesial infections is diverse and the systemic inflammatory response induced by infection is considered to be a major feature of the pathophysiology of canine babesiosis. An experimental case-controlled longitudinal study was conducted to assess the clinical, haematological, cytokine and acute phase protein changes that occur during experimental B. gibsoni infection of beagle puppies. Infected dogs became transiently pyrexic and anaemic, intermittently neutropenic and transiently, but profoundly, thrombocytopenic, although this had no apparent adverse clinical effect. Experimental B. gibsoni infection also induced an acute phase response, characterised by a marked increase in the concentration of C-reactive protein, which was delayed in onset following infection but preceded the detection of peripheral parasitaemia. Experimental B. gibsoni infection was also associated with marked increases in the concentration of multiple cytokines which were also delayed in onset following infection and occurred subsequent to the detection of peripheral parasitaemia and the acute phase response. This study furthers our understanding of the immune response that occurs during babesial infections and the role that systemic inflammation plays in the pathophysiology of canine babesiosis.

Longitudinal annoyance responses to a road traffic noise management strategy that reduced heavy vehicles at night.

A traffic management strategy was designed to reduce trucks using an urban corridor. The intervention had potential to affect night-time truck flows, but did not target truck traffic in the day, or vehicles other than trucks at any hour. A two-year long panel study measured the community's response to this intervention, using five repeated measurements of response. There were significant reductions in the panel's response to noise, both for night-time annoyance and for interference with activities. This was remarkable given that noise monitoring showed that the intervention produced no change in conventional traffic noise indicators. However, there were measureable changes in the number of articulated truck movements at night, and the benefit can be attributed to reduction in the number of noise events from heavy vehicles. The parallel tracking of changes in reported noise effects and the numbers of heavy vehicles in the night hours in this longitudinal study provides strong support to the notion that noise effects at night depend on the number of noise events experienced, not only on the overall level of traffic noise. The latter appear to be unresponsive indicators by which to assess the noise-effect benefit of heavy vehicle reduction strategies.

Perceptual constancy in auditory perception of distance to railway tracks.

Distance to a sound source can be accurately estimated solely from auditory information. With a sound source such as a train that is passing by at a relatively large distance, the most important auditory information for the listener for estimating its distance consists of the intensity of the sound, spectral changes in the sound caused by air absorption, and the motion-induced rate of change of intensity. However, these cues are relative because prior information/experience of the sound source-its source power, its spectrum and the typical speed at which it moves-is required for such distance estimates. This paper describes two listening experiments that allow investigation of further prior contextual information taken into account by listeners-viz., whether they are indoors or outdoors. Asked to estimate the distance to the track of a railway, it is shown that listeners assessing sounds heard inside the dwelling based their distance estimates on the expected train passby sound level outdoors rather than on the passby sound level actually experienced indoors. This form of perceptual constancy may have consequences for the assessment of annoyance caused by railway noise.

Health effects of green tea catechins in overweight and obese men: a randomised controlled cross-over trial.

Regular consumption of green tea may be cardioprotective. In the present study we investigated the health effects of dietary supplementation with green tea catechins and the potential modifying effect of the catechol-O-methyltransferase (COMT) Val/Met genotype. Subjects (sedentary males, aged 40-69 years, with BMI ≥ 28 and ≤ 38 kg/m(2)) were randomly assigned to consume decaffeinated green tea extract (DGT; 530 mg containing about 400 mg total catechins/capsule, twice daily) and placebo in a complete cross-over design. Ambulatory blood pressure and biomarkers of metabolic function (cholesterol, TAG, glucose and insulin) were measured at weeks 0 and 6. Although a marked increase in the concentration of plasma epigallocatechin gallate (EGCG), urinary epigallocatechin (EGC) and urinary 4'-O-methyl EGC was found after DGT treatment, no effect on blood pressure or biomarkers of metabolic function was observed. However, a period × treatment interaction (P < 0·05) was detected for body-weight change. Despite a similar increase in estimated energy intake during intervention period 1, body weight decreased by 0·64 (sd 2·2) kg and increased by 0·53 (sd 1·9) kg in the DGT and placebo groups, respectively (P = 0·025), suggesting a protective effect of green tea catechins on weight gain. Additionally, the COMT Val/Met genotype influenced urinary accumulation of EGC and 4'-O-methyl EGC (P < 0·01). Mean concentrations were lower in individuals homozygous for the high-activity G-allele, possibly reflecting increased metabolic flux and a more rapid conversion to downstream metabolic species, compared with individuals carrying at least one copy of the low-activity A-allele. Additional studies are needed to confirm these findings and further explore the modifying effect of genotype.

Extended phenotypes on coral reefs: cryptic phenotypes modulate coral-vermetid interactions.

Phenotypic variation can lead to variation in the strength and outcome of species interactions. Variation in phenotypic traits can arise due to plastic responses to environmental stimuli, underlying genetic variation, or both, and may reflect differences in the focal organism or aspects of the extended phenotype (e.g., associated microbes). We used a reciprocal transplant experiment of Porites corals to evaluate the role of plasticity vs. heritable diversity on phenotypic traits and performance of corals that varied in their prior exposure to vermetid gastropods, an organism known to reduce coral growth and survival. We measured a suite of phenotypic traits associated with coral performance, many of which showed a plastic response to vermetid exposure. Vermetids decreased calcification of corals, increased microbial diversity, and shifted microbial composition. Most traits also showed a signature of previous exposure environment that persisted even when exposure was reversed: i.e., under the same conditions, corals naïve to vermetids had slower calcification rates, thicker tissues, higher Symbiodiniaceae densities, and different microbiomes than corals previously exposed to vermetids. We suggest the phenotypic differences are heritable, as reefs with and without vermetids were comprised of two different mitotypes, that revealed high, consistent genetic variation. Vermetids were only found on the fast-growing coral mitotype that was characterized by thin tissue, and that likely had a history of disturbance. As extended phenotypes can have community impacts, we suggest vermetid, in addition to microbes, are part of the extended community phenotype of these corals. Coral genotypes can establish different reef trajectories, with thin-tissue types more prone to disturbance and subsequent colonization by other species, like vermetids, which can further facilitate the degradation of coral reefs. The effects of the extended phenotype of species likely influence heterogeneity across landscapes as well as temporal differences in community composition.

An electron microscope study of canine cardiac myosin and some of its aggregates.

The morphology of the canine cardiac myosin molecule has been investigated in the electron microscope with Hall's mica-replica technique. The molecule is an elongated rod (shaft) of nonuniform diameter with a globular expansion (head) on one end. Statistical analysis of the lengths of 1908 molecules showed that the mean length was 1610 +/- 250 A; the mean length of the head was 210 +/- 20 A; and the diameter of the head and that of the shaft were 35 to 40 and 15 to 20 A, respectively. About one-third of the molecules had single or multiple, fairly sharp, angulations along their shafts. Rarely, some details of the substructure of the molecule have been observed. Large, spindle-shaped aggregates, measuring 0.5 to 1 micro in length and 50 to 100 A in diameter, were produced by dilution of the myosin solutions. These aggregates were readily visualized in the electron microscope by means of Huxley's negative-staining technique. Projections often were visible along the length of the aggregates except at a central zone where they were frequently absent. The aggregates resembled the thick myofilaments of the myocardium and appeared similar to those produced by Huxley from skeletal myosin solutions.

Thermosensitivity of a DNA recognition site: activity of a truncated nutL antiterminator of coliphage lambda.

Antitermination is an important transcriptional control. In bacteriophage lambda, the presence of the nut antiterminators between the promoters and terminators results in relatively unhindered transcription when the lambda N gene product and necessary host factors are supplied. This antitermination system has been rendered thermosensitivity by modification of the nut site. A fragment of lambda DNA [74 base pairs (bp) in length]that contained the 17-bp nutL core sequence, but lacked the 8-bp boxA sequence, was cloned in a pp-N-tL1-galK plasmid between the pp promoter and gene N. This fragment mediated antitermination of transcription at 30 degrees C, as measured by assaying galK gene expression in Escherichia coli. At 42 degrees C, however, antitermination at the lambda tL1 terminator was abolished. Antitermination at 42 degrees C was restored by replacing the 74-bp nutL fragment with longer sequences containing both nutL and boxA or by cloning a synthetic boxA sequence ahead of the 74-bp nutL fragment. Thus, efficient antitermination required both boxA and the 17-bp nutL core, with the latter becoming conditionally defective when the boxA sequence was deleted.

Response to a change in transport noise exposure: competing explanations of change effects.

Annoyance response to a change in noise exposure appears to demonstrate an excess response relative to those predicted from exposure-response curves obtained under steady-state conditions. This change effect also appears to persist well after the change. Numerous explanations have been postulated for this phenomenon. This paper catalogs the different explanations and reviews the evidence for each. The evidence is of limited and variable quality but, while inadequate to endorse any one explanation, is sufficient to reject some notions and to identify a residual set of plausible explanations. These include two explanations based on modifiers of exposure-response relationships that potentially change between before and after conditions, an explanation based on differential response criteria of respondents chronically exposed to different steady-state levels of noise, and an explanation based on retention of coping strategies. All have ramifications for the assessment of human response (annoyance) where noise exposure changes, and some have wider implications for the interpretation of generalized exposure-response curves obtained in the steady state.

Response to a change in transport noise exposure: a review of evidence of a change effect.

Environmental appraisals of transport infrastructure plans are generally conducted in situations where there will be a step change, or an abrupt change, in noise exposure. While there has been a number of studies of response to step changes in exposure, and seven previous reviews of subsets of these studies, understanding of human response to a change in noise exposure remains limited. Building largely on these previous reviews, this paper examines the evidence that when noise exposure is changed, subjective reaction may not change in the way that would be predicted from steady-state exposure-response relationships. The weight of evidence, while not incontrovertible, is that when exposure changes, responses show an excess response compared to responses predicted from steady-state exposure-response relationships. That is, there is a change effect in addition to an exposure effect--at least for road studies and at least where the change in exposure results from changes at the source. Further, there appears to be little, if any, adaptation of this excess response with time.

Differential effects on gene transcription and hematopoietic differentiation correlate with GATA2 mutant disease phenotypes.

Heterozygous GATA2 mutations underlie an array of complex hematopoietic and lymphatic diseases. Analysis of the literature reporting three recurrent GATA2 germline (g) mutations (gT354M, gR396Q and gR398W) revealed different phenotype tendencies. Although all three mutants differentially predispose to myeloid malignancies, there was no difference in leukemia-free survival for GATA2 patients. Despite intense interest, the molecular pathogenesis of GATA2 mutation is poorly understood. We functionally characterized a GATA2 mutant allelic series representing major disease phenotypes caused by germline and somatic (s) mutations in zinc finger 2 (ZF2). All GATA2 mutants, except for sL359V, displayed reduced DNA-binding affinity and transactivation compared with wild type (WT), which could be attributed to mutations of arginines critical for DNA binding or amino acids required for ZF2 domain structural integrity. Two GATA2 mutants (gT354M and gC373R) bound the key hematopoietic differentiation factor PU.1 more strongly than WT potentially perturbing differentiation via sequestration of PU.1. Unlike WT, all mutants failed to suppress colony formation and some mutants skewed cell fate to granulocytes, consistent with the monocytopenia phenotype seen in GATA2-related immunodeficiency disorders. These findings implicate perturbations of GATA2 function shaping the course of development of myeloid malignancy subtypes and strengthen complete or nearly complete haploinsufficiency for predisposition to lymphedema.

Resistance to arteriosclerosis in pigs with von Willebrand's disease. Spontaneous and high cholesterol diet-induced arteriosclerosis.

The aortas of 11 pigs (aged 1-3 yr) with homozygous von Willebrand's disease (vWd) were compared with those of 11 normal pigs of the same ages. Six of the controls exhibited multiple arteriosclerotic plaques with intimal thickening of 63-130 mum. In contrast, none of the pigs with vWd had multiple plaques, and only one had a lesion >2 mm in diameter. In a subsequent study, 3-mo-old pigs (11 controls and 7 with homozygous vWd) were placed on a 2% cholesterol diet for up to 6 mo. All of the controls developed arteriosclerotic plaques in the aorta, and in nine of the controls, at least 13% of the entire surface was involved. Intimal thickness ranged up to 390 mum. In contrast, four of the pigs with vWd did not develop such lesions, two developed arteriosclerotic lesions affecting 6 and 7% of the aortic surface, and the seventh had 13% of the aortic surface involved. Most of the pigs with vWd, however, developed flat fatty lesions in contrast to the normal pigs whether on the normal or the high cholesterol diet. There was blue staining of the flat fatty lesions when two pigs with vWd were injected with Evans blue dye antemortem. By electron microscopy, severe endothelial damage was apparent, but there was no intimal proliferation. The coincidence of the impaired platelet-arterial wall interaction and lack of arteriosclerosis in this bleeding disease is discussed.

DNA ploidy in proliferative verrucous leukoplakia.

Proliferative verrucous leukoplakia (PVL) is a clinicopathologically distinctive form of oral leukoplakia presenting with multifocal flat, nodular and verrucous lesions that progress inexorably to squamous carcinoma. The aims of this investigation were to describe the clinical and histopathological features of six cases of PVL and to determine whether lesional epithelium demonstrates DNA ploidy anomalies prior to malignant transformation. The clinical and pathological features of six patients were reviewed and all biopsy specimens were subjected to image-based DNA ploidy analysis. The female:male ratio was 5:1 and the average age on first biopsy was 66 years. Only one patient reported both tobacco smoking and alcohol intake. The most frequently affected sites were alveolar ridge and/or gingiva (6/6), buccal mucosa (3/6), palate (3/6), tongue (2/6), buccal sulcus (2/6), and lip (1/6). Three patients developed multiple primary carcinomas, either invasive or verrucous. A ploidy anomaly at any oral site would have predicted malignant transformation in four cases and probably in a fifth for whom DNA ploidy failed to meet diagnostic criteria but was suspicious of aneuploidy. The site of transformation was predicted by ploidy and histopathology for three carcinomas and a further carcinoma showed severe dysplasia and a suspicious ploidy result in adjacent tissue. Both conventional histopathology and DNA ploidy proved effective in predicting the site of transformation in this limited series.

Demographic, belief, and situational factors influencing the decision to utilize emergency medical services among chest pain patients. Rapid Early Action for Coronary Treatment (REACT) study.

BACKGROUND: Empirical evidence suggests that people value emergency medical services (EMS) but that they may not use the service when experiencing chest pain. This study evaluates this phenomenon and the factors associated with the failure to use EMS during a potential cardiac event. METHODS AND RESULTS: Baseline data were gathered from a randomized, controlled community trial (REACT) that was conducted in 20 US communities. A random-digit-dial survey documented bystander intentions to use EMS for cardiac symptoms in each community. An emergency department surveillance system documented the mode of transport among chest pain patients in each community and collected ancillary data, including situational factors surrounding the chest pain event. Logistic regression identified factors associated with failure to use EMS. A total of 962 community members responded to the phone survey, and data were collected on 875 chest pain emergency department arrivals. The mean proportion of community members intending to use EMS during a witnessed cardiac event was 89%; the mean proportion of patients observed using the service was 23%, with significant geographic differences (range, 10% to 48% use). After controlling for covariates, non-EMS users were more likely to try antacids/aspirin and call a doctor and were less likely to subscribe to (or participate in) an EMS prepayment plan. CONCLUSIONS: The results of this study indicate that indecision, self-treatment, physician contact, and financial concerns may undermine a chest pain patient's intention to use EMS.

Cloning of the rat insulin-like growth factor-binding protein-2 gene and identification of a functional promoter lacking a TATA box.

We have isolated clones encoding the rat insulin-like growth factor-binding protein-2 (IGFBP-2) gene and determined its organization and nucleotide sequence. The rat IGFBP-2 gene spans at least 8 kilobases and consists of four exons, each of which contains protein-coding sequences. The amino acid sequences of exons 1, 3, and 4 are 32-50% identical to the corresponding exons of human IGFBP-1 and IGFBP-3, and 87-91% identical to those of human IGFBP-2. The 18 cysteines in the mature binding proteins are conserved. Exon 2 shows negligible homology. Primer-extended reverse transcription indicated that the 5' end of IGFBP-2 mRNA is 151 nucleotides up-stream from the translation start site [designated nucleotide (nt) -151]. Consistent with this result, IGFBP-2 mRNA protected a genomic fragment terminating at approximately nt -148, as well as smaller fragments. A 1260 nt fragment containing 1144 nt of 5' flanking region had promoter activity when inserted in the correct orientation into a plasmid containing a promoterless luciferase reporter gene and transiently transfected into BRL-3A rat liver cells, which express IGFBP-2, but not when transfected into H4-II-E cells, which do not express IGFBP-2. The IGFBP-2 gene lacks a TATA box immediately up-stream from the transcription initiation site. It is GC rich (66% between nt -270 and +385) and contains GC boxes that might be recognized by transcription factors Sp1 or ETF. The promoter region contains multiple direct and indirect repeats. One direct repeat contains a variant Sp1 site (-158 to -150) near the consensus Sp1 site at nt -138 to -130. The 5' flanking region also contains motifs that might be recognized by transcription factors AP-1 (Jun/Fos), AP-2, and liver factor B1. The role of these sites in basal and regulated expression of the IGFBP-2 gene remains to be determined.

Structure of the rat insulin-like growth factor II transcriptional unit: heterogeneous transcripts are generated from two promoters by use of multiple polyadenylation sites and differential ribonucleic acid splicing.

The rat insulin-like growth factor II (rIGF-II) gene, which exists as a single copy in the genome, is expressed as a multitranscript family of mRNA molecules ranging in size from 4.6 to 1 kilobases. Part of this heterogeneity can be ascribed to the presence of two different promoters, each transcribing alternative 5'-noncoding regions which are spliced to common coding exons. In the present study we use a combination of DNA sequence analysis of the gene, mapping of the mRNA molecules by Northern analysis and ribonuclease protection experiments, and DNA sequence analysis of cDNA clones complementary to different regions of the genome to establish the structure of several rIGF-II mRNA species. These results indicate that RNA heterogeneity also arises from the use of different polyadenylation sites. In addition, a variant 2 kilobases RNA was observed that was colinear with the distal 1700 base pairs of the 3147 base pair long exon 3, and may arise by alternative RNA splicing. These posttranscriptional modifications of RNAs arising from the rIGF-II transcription unit may generate molecules with different functional potential.

The expression pattern of an insulin-like growth factor (IGF)-binding protein gene is distinct from IGF-II in the midgestational rat embryo.

Insulin-like growth factor-II (IGF-II), the predominant form of IGF in fetal and neonatal serum and tissues, is found in vivo complexed with IGF-binding proteins. One of these binding proteins, IGFBP-2, is present at high levels in fetal rat plasma and binds both IGF-I and IGF-II with high affinity. We here have used in situ hybridization to compare the distribution of IGFBP-2 mRNA with that of IGF-II mRNA in embryonic day 13.5-15 rat embryos. The spatial patterns of IGF-II and IGFBP-2 expression in the fetal trunk were distinct and, in general, nonoverlapping. Most mesoderm derivatives that express IGF-II at high levels contained little, if any, IGFBP-2 mRNA. Instead, IGFBP-2 mRNA was expressed at high levels in many cell types derived from ectoderm and endoderm. The expression of IGFBP-2 mRNA in the central nervous system (CNS) during this developmental period was examined in particular detail. The three most prominent sites of IGFBP-2 expression in the CNS were comprised of cells with nonneuronal phenotypes: 1) the epithelium of the choroid plexus, a tissue that produces cerebrospinal fluid; 2) the floor plate, an area that can guide axonal outgrowth from commissural neurons of the spinal cord in vitro; and 3) the infundibulum, the progenitor of the posterior pituitary that is believed to influence differentiation of the adjacent intermediate pituitary.(ABSTRACT TRUNCATED AT 250 WORDS)

Transcription of the insulin-like growth factor-binding protein-2 gene is increased in neonatal and fasted adult rat liver.

The insulin-like growth factor-binding proteins (IGFBPs) are a family of proteins that specifically bind IGF-I and IGF-II, determine their bioavailability to tissues, and modulate their actions in target tissues. Levels of IGFBPs in plasma and IGFBP mRNAs in liver are highly regulated with developmental age and metabolic status. We now demonstrate that the increase in IGFBP-2 mRNA in fasted adult rat liver and in the liver of normal neonatal rats reflects an increased rate of transcription. When adult rats were fasted for 2-3 days, IGFBP-2 mRNA was increased in liver, but not in brain or kidney. The increase in hepatic IGFBP-2 mRNA was observed after only 1 day of fasting. Levels decreased by half after 6 h of refeeding and returned to their low starting values after 2 days of refeeding. Transcription-elongation experiments indicated that transcription of the IGFBP-2 gene was increased in fasted liver. The rate of transcription increased 9.2- +/- 3.5-fold for transcripts labeled in exon 1 and 6.6- +/- 2.4-fold for transcripts labeled in exons 2, 3, and 4, suggesting that fasting causes a uniform increase in the number of RNA polymerase II molecules along the length of the IGFBP-2 gene. We infer from these results that the regulation of IGFBP-2 gene transcription in fasting occurs at the level of initiation rather than elongation. IGFBP-2 gene transcription also was increased 3.8- +/- 1.2-fold (exon 1) and 2.9- +/- 0.9-fold (exons 2, 3, and 4) in nuclei from 2-day postnatal rat liver compared with adult rat liver, consistent with the greater abundance of IGFBP-2 mRNA in neonatal rat liver.