Validation of the Kinetik Blood Pressure Monitor-Series 1 for use in adults at home and in clinical settings, according to the 2002 European Society of Hypertension International Protocol on the validation of blood pressure devices.

The aim of this study was to assess the blood pressure (BP) measurement accuracy of the Kinetik Blood Pressure Monitor-Series 1 (BPM-1) for use in home or clinical settings according to the 2002 European Society of Hypertension International Protocol (ESH-IP). Forty-two participants were recruited to fulfil the required number of systolic and diastolic BP measurements according to the ESH-IP. Nine sequential same-arm BP readings were measured and analysed for each participant using the test device and observer mercury standard readings according to the 2002 ESH-IP. Forty one participants were used to obtain 33 sets of systolic and diastolic BP readings and were included in the analysis. Mean difference between the device measurements and the observer (mercury standard) measurements was 1.1 ± 7.2/1.1 ± 6.8 mmHg (mean ± standard deviation; systolic/diastolic). The number of systolic BP differences between the test and observer measurements that fell within 5, 10 and 15 mmHg was 65, 86 and 92. For diastolic readings, the number of test-observer measurement differences within 5, 10 and 15 mmHg was 77, 91 and 94. The number of participants with at least two out of three differences within 5 mmHg was 28 for systolic and 40 for diastolic BP readings. Three participants had no differences between the test and observer measurements within 5 mmHg in both the systolic and diastolic measurement categories. The Kinetik BPM-1 device fulfilled the requirements of the ESH-IP validation procedure and can be recommended for clinical use and self-measurement within the home.

Upconverted electroluminescence via Auger scattering of interlayer excitons in van der Waals heterostructures.

The intriguing physics of carrier-carrier interactions, which likewise affect the operation of light emitting devices, stimulate the research on semiconductor structures at high densities of excited carriers, a limit reachable at large pumping rates or in systems with long-lived electron-hole pairs. By electrically injecting carriers into WSe2/MoS2 type-II heterostructures which are indirect in real and k-space, we establish a large population of typical optically silent interlayer excitons. Here, we reveal their emission spectra and show that the emission energy is tunable by an applied electric field. When the population is further increased by suppressing the radiative recombination rate with the introduction of an hBN spacer between WSe2 and MoS2, Auger-type and exciton-exciton annihilation processes become important. These processes are traced by the observation of an up-converted emission demonstrating that excitons gaining energy in non-radiative Auger processes can be recovered and recombine radiatively.

BAG-1 enhances cell-cell adhesion, reduces proliferation and induces chaperone-independent suppression of hepatocyte growth factor-induced epidermal keratinocyte migration.

Cell motility is important in maintaining tissue homeostasis, facilitating epithelial wound repair and in tumour formation and progression. The aim of this study was to determine whether BAG-1 isoforms regulate epidermal cell migration in in vitro models of wound healing. In the human epidermal cell line HaCaT, endogenous BAG-1 is primarily nuclear and increases with confluence. Both transient and stable p36-Bag-1 overexpression resulted in increased cellular cohesion. Stable transfection of either of the three human BAG-1 isoforms p36-Bag-1 (BAG-1S), p46-Bag-1 (BAG-1M) and p50-Bag-1 (BAG-1L) inhibited growth and wound closure in serum-containing medium. However, in response to hepatocyte growth factor (HGF) in serum-free medium, BAG-1S/M reduced communal motility and colony scattering, but BAG-1L did not. In the presence of HGF, p36-Bag-1 transfectants retained proliferative response to HGF with no change in ERK1/2 activation. However, the cells retained E-cadherin localisation at cell-cell junctions and exhibited pronounced cortical actin. Point mutations in the BAG domain showed that BAG-1 inhibition of motility is independent of its function as a chaperone regulator. These findings are the first to suggest that BAG-1 plays a role in regulating cell-cell adhesion and suggest an important function in epidermal cohesion.

Hsp70 suppresses apoptosis in sympathetic neurones by preventing the activation of c-Jun.

The anti-apoptotic effects of heat-shock protein (Hsp70) were assessed in SCG neurones following nerve growth factor (NGF) withdrawal. The results showed that the virally mediated expression of Hsp70 mirrored the effects of the c-Jun-N-terminal kinase (JNK) binding domain (JBD) of JNK interacting protein (an inhibitor of JNK and c-Jun activation) and suppressed the phosphorylation of c-Jun. Preventing c-Jun transcriptional activity subsequently led to reduced cytochrome c release and prevented caspase activation as indicated by a decrease in poly (ADP-ribose) polymerase-1 (PARP) cleavage. Together, these results show that Hsp70 is a highly effective inhibitor of apoptosis in sympathetic neurones and that it mediates this effect primarily by suppressing c-Jun transcriptional signalling.

Hsp40 molecules that target to the ubiquitin-proteasome system decrease inclusion formation in models of polyglutamine disease.

We studied the ability of heat shock, DnaJ-like-1 (HSJ1) proteins (which contain DnaJ and ubiquitin-interacting motifs) to reduce polyglutamine-mediated inclusion formation. The experiments demonstrated that expression of heat shock protein 70 (hsp70), hsp40, HSJ1a, and HSJ1b significantly reduced protein inclusion formation in a model of spinal and bulbar muscular atrophy (SBMA). HSJ1a also mediated a significant decrease in the number of inclusions formed in a primary neuronal model of protein aggregation. Studies to elucidate the mechanisms underlying these reductions showed that hsp70 and hsp40 increased chaperone-mediated refolding. In contrast, expression of HSJ1 proteins did not promote chaperone activity but caused an increase in ubiquitylation. Furthermore, HSJ1a was associated with a ubiquitylated luciferase complex, and in the presence of HSJ1a but not an HSJ1a UIM mutant (HSJ1a-deltaUIM) there was a reduction in luciferase protein levels. Together these results show that HSJ1 proteins mediated an increase in target protein degradation via the ubiquitin-proteasome system (UPS). We also found that the expression of HSJ1a significantly decreased the number of neurons containing inclusions in an in vivo model of polyglutamine disease. These findings indicate that targeted modification of the UPS to facilitate degradation of misfolded proteins may represent a highly effective therapeutic avenue for the treatment of polyglutamine disease.

Hsp40 Molecules That Target to the Ubiquitin-proteasome System Decrease Inclusion Formation in Models of Polyglutamine Disease.

We studied the ability of heat shock, DnaJ-like-1 (HSJ1) proteins (which contain DnaJ and ubiquitin-interacting motifs) to reduce polyglutamine-mediated inclusion formation. The experiments demonstrated that expression of heat shock protein 70 (hsp70), hsp40, HSJ1a, and HSJ1b significantly reduced protein inclusion formation in a model of spinal and bulbar muscular atrophy (SBMA). HSJ1a also mediated a significant decrease in the number of inclusions formed in a primary neuronal model of protein aggregation. Studies to elucidate the mechanisms underlying these reductions showed that hsp70 and hsp40 increased chaperone-mediated refolding. In contrast, expression of HSJ1 proteins did not promote chaperone activity but caused an increase in ubiquitylation. Furthermore, HSJ1a was associated with a ubiquitylated luciferase complex, and in the presence of HSJ1a but not an HSJ1a UIM mutant (HSJ1a-ΔUIM) there was a reduction in luciferase protein levels. Together these results show that HSJ1 proteins mediated an increase in target protein degradation via the ubiquitin-proteasome system (UPS). We also found that the expression of HSJ1a significantly decreased the number of neurons containing inclusions in an in vivo model of polyglutamine disease. These findings indicate that targeted modification of the UPS to facilitate degradation of misfolded proteins may represent a highly effective therapeutic avenue for the treatment of polyglutamine disease.

Coordinated expression of sulfate uptake and components of the sulfate assimilatory pathway in maize.

A high-affinity-type sulfate transporter (Group 1: ZmST1;1, Accession No. AF355602) has been cloned from maize seedlings by RT-PCR. Tissue and cell specific localisation of this sulfate transporter has been determined along the developmental gradient of the root and in leaves of different ages. In S-sufficient conditions there was uniform low expression of ZmST1;1 in the root and very low expression in the leaves. Increased mRNA abundance and sulfate influx capacity indicated that S-starvation increased ZmST1;1 expression in roots, especially at the top of the root (just behind the seed, the area possessing most laterals and root hairs) compared to the root tip. Similarly a group 2, probable low affinity-type sulfate transporter, ZmST2;1, and also ATP-sulfurylase and APS-reductase but not OAS(thiol)lyase were induced by S-starvation and showed highest expression in the upper section of the root. S-starvation increased root/shoot ratio by 20 % and increased root lateral length and abundance in the region closest to the root tip. As the increase in root proliferation was not as great as the increase in mRNA pools, it was clear that there was a higher cellular abundance of the mRNAs for sulfate transporters, ATP-sulfurylase, and APS-reductase in response to sulfur starvation. In the leaves, the sulfate transporters, ATP-sulfurylase and APS-reductase were induced by S-starvation with the most mature leaf showing increased mRNA abundance first. In situ hybridization indicated that ZmST1;1 was expressed in epidermal and endodermal cell layers throughout the root whilst OAS(thiol)lyase was highly expressed in the root cortex.

Metabolic and structural viability of precision-cut rat lung slices in culture.

1. The principal objective was to evaluate the functional and structural integrity of precision-cut rat lung slices in culture over 72 h. 2. Lung slices metabolized 7-ethoxycoumarin in a time-dependent fashion, the major metabolites being the sulphate and glucuronide of 7-hydroxycoumarin with very low levels of the free compound. Prior treatment of rats with beta-naphthoflavone elevated markedly the rate of metabolism. The optimum slice thickness, as exemplified by the metabolism of 7-ethoxycoumarin, was about 600 microm. 3. Lung slices retained metabolic viability towards 7-ethoxycoumarin for 8 h, but after this point a marked decline in metabolic activity was noted. However, very low levels of activity were still evident following a 72 h incubation. 4. Morphological examination of lung slices revealed nuclear degeneration and loss of tissue architecture following 24h incubation. When cellular integrity was assessed using lactate dehydrogenase, a time-dependent leakage was evident with maximum loss occurring within 24h; longer incubations did not result in further leakage. 5. It is concluded that precision-cut rat lung slices, of 600 microm thickness, can be maintained metabolically viable in culture for some 8 h.

Hematotoxicity response in rats by the novel copper-based anticancer agent: casiopeina II.

The in vivo toxicity of the novel copper-based anticancer agent, casiopeina II (Cu(4,7-dimethyl-1,10-phenanthroline)(glycine)NO3) (CII), was investigated. Casiopeinas are a family of copper-coordinated complexes that have shown promising anticancer activity. The major toxic effect attributed to a single i.v. administration of CII (5 mg/kg dose) in the rat was an hemolytic anemia (reduced hemoglobin concentration (HB), red blood cell (RBC) count and packed cell volume (PCV) accompanied by a marked neutrophilic leukocytosis) 12 h and 5 days after administration, attributed to a direct erythrocyte damage. Increased reticulocyte levels and presence of normoblasts in peripheral blood 5 days post-administration indicated an effective erythropoietic response with recovery at 15 days. Increase in spleen weight and the morphological evidence of congestion of the red pulp (RP) with erythrocytes (E) resulting in a higher ratio of red to white pulp (WP) was consistent with increased uptake of damaged erythrocytes by the reticuloendothelial system observed by histopathology and electron microscopy. Extramedullary hemopoiesis was markedly increased at 5 days giving further evidence of a regenerative erythropoietic response that had an effective recovery by 15 days. Morphological changes in spleen cellularity were consistent with hematotoxicity, mainly a reduction of the red pulp/white pulp ratio, increase in erythrocyte content at 12 h, and an infiltration of nucleated cells in the red pulp at 5 days, with a tendency towards recovery 15 days after administration. The erythrocyte damage is attributed to generation of free radicals and oxidative damage on the membrane and within cells resulting from the reduction of Cu(II) and the probable dissociation of the CII complex.

Intermolecular interactions in two (ferrocenylmethyl)benzimidazoles incorporating the 4-MeOC6H4 and 3,4-(MeO)2C6H3 groups: analysis of MeO-C-C distortions from ideal 120 degrees geometry.

The title compounds, 1-ferrocenylmethyl-2-(4-methoxyphenyl)-1H-benzimidazole, [Fe(C5H5)(C20H17N2O)], (I), and 2-(3,4-dimethoxyphenyl)-1-ferrocenylmethyl-1H-benzimidazole, [Fe(C5H5)(C21H19N2O2)], (II), are model electroactive compounds for anion sensor and antimalarial applications. Distortions from the ideal 120 degrees angle about the MeO-C-C groups are evident, with angles of 115.1 (2) and 125.0 (2) degrees in (I), and 115.9 (2) and 124.6 (2) degrees, and 115.7 (2) and 125.1 (2) degrees in (II). The main intermolecular hydrogen bonds in (I) comprise C-H.N and C-H.pi(C5H5) interactions, while in (II), only weak C-H.pi(imidazole) and C-H.pi(arene) interactions are present.

Effects on male rats of di-(2-ethylhexyl) phthalate and di-n-hexylphthalate administered alone or in combination.

The effects of phthalate esters of branched chain alcohols, typified by di-(2-ethylhexyl)phthalate (DEHP) differ from those of esters of straight chain alcohols typified by di-n-hexyl phthalate (DnHP). The former induce liver enlargement and proliferation of hepatic peroxisomes, while the latter cause no peroxisome proliferation but cause fat accumulation in the liver. Both classes of phthalate esters are hypolipidaemic and cause thyroid changes associated with an increased rate of thyroglobulin turnover. As phthalate esters are used as mixtures, we have examined the effect of mixtures of the compounds. Groups of five male Wistar albino rats were administered either control diet or diets containing either 10000 ppm of DEHP, 10000 ppm of DnHP or 10000 ppm DEHP plus 10000 ppm DnHP for 14 days. Rats receiving diets containing DEHP showed the expected increase in relative liver weight, in "peroxisomal" fatty acid oxidation and in CYP4A1. Serum triglyceride and serum cholesterol were also reduced, and the thyroid showed the histological changes mentioned above. Rats consuming diets containing DnHP showed no increase in relative liver weight and no induction of peroxisomal fatty acid oxidation or CYP4A1. However, there was a marked accumulation of fat in the liver. The fall in serum cholesterol was similar to that in rats treated with DEHP, but the fall of serum triglyceride was more pronounced. Thyroidal changes were again observed. In general, changes in rats treated with a mixture of DEHP and DnHP were very similar to those found with rats treated with DEHP alone. The liver was enlarged, and peroxisomal fatty acid oxidation and CYP4A1 were both induced. The amount of fat in the liver was much less than in rats receiving DnHP alone. Thyroid changes were similar to those in rats receiving the individual compounds. The effect on serum cholesterol seemed additive, but the levels of serum triglyceride were intermediate between the groups receiving the single compounds.

Simple 1,2-aminoalcohols as strain-specific antimalarial agents.

We report here the in vitro activity of a selection of 1, 2-aminoalcohol-containing compounds against cloned strains of human Plasmodium falciparum. These compounds exhibit moderate antimalarial activity but a high degree of strain specificity, preferentially inhibiting a chloroquine-resistant strain of the organism.

The use of cluster sampling to determine aid needs in Grozny, Chechnya in 1995.

War broke out in Chechnya in November 1994 following a three-year economic blockade. It caused widespread destruction in the capital Grozny. In April 1995 Medical Relief International--or Merlin, a British medical non-governmental organisation (NGO)--began a programme to provide medical supplies, support health centres, control communicable disease and promote preventive health-care in Grozny. In July 1995 the agency undertook a city-wide needs assessment using a modification of the cluster sampling technique developed by the Expanded Programme on Immunisation. This showed that most people had enough drinking-water, food and fuel but that provision of medical care was inadequate. The survey allowed Merlin to redirect resources earmarked for a clean water programme towards health education and improving primary health-care services. It also showed that rapid assessment by a statistically satisfactory method is both possible and useful in such a situation.

Protein global fold determination using site-directed spin and isotope labeling.

We describe a simple experimental approach for the rapid determination of protein global folds. This strategy utilizes site-directed spin labeling (SDSL) in combination with isotope enrichment to determine long-range distance restraints between amide protons and the unpaired electron of a nitroxide spin label using the paramagnetic effect on relaxation rates. The precision and accuracy of calculating a protein global fold from only paramagnetic effects have been demonstrated on barnase, a well-characterized protein. Two monocysteine derivatives of barnase, (H102C) and (H102A/Q15C), were 15N enriched, and the paramagnetic nitroxide spin label, MTSSL, attached to the single Cys residue of each. Measurement of amide 1H longitudinal relaxation times, in both the oxidized and reduced states, allowed the determination of the paramagnetic contribution to the relaxation processes. Correlation times were obtained from the frequency dependence of these relaxation processes at 800, 600, and 500 MHz. Distances in the range of 8 to 35 A were calculated from the magnitude of the paramagnetic contribution to the relaxation processes and individual amide 1H correlation times. Distance restraints from the nitroxide spin to amide protons were used as restraints in structure calculations. Using nitroxide to amide 1H distances as long-range restraints and known secondary structure restraints, barnase global folds were calculated having backbone RMSDs <3 A from the crystal structure. This approach makes it possible to rapidly obtain the overall topology of a protein using a limited number of paramagnetic distance restraints.

Solution structures of the C-terminal domain of cardiac troponin C free and bound to the N-terminal domain of cardiac troponin I.

The N-terminal domain of cardiac troponin I (cTnI) comprising residues 33-80 and lacking the cardiac-specific amino terminus forms a stable binary complex with the C-terminal domain of cardiac troponin C (cTnC) comprising residues 81-161. We have utilized heteronuclear multidimensional NMR to assign the backbone and side-chain resonances of Ca2+-saturated cTnC(81-161) both free and bound to cTnI(33-80). No significant differences were observed between secondary structural elements determined for free and cTnI(33-80)-bound cTnC(81-161). We have determined solution structures of Ca2+-saturated cTnC(81-161) free and bound to cTnI(33-80). While the tertiary structure of cTnC(81-161) is qualitatively similar to that observed free in solution, the binding of cTnI(33-80) results mainly in an opening of the structure and movement of the loop region between helices F and G. Together, these movements provide the binding site for the N-terminal domain of cTnI. The putative binding site for cTnI(33-80) was determined by mapping amide proton and nitrogen chemical shift changes, induced by the binding of cTnI(33-80), onto the C-terminal cTnC structure. The binding interface for cTnI(33-80), as suggested from chemical shift changes, involves predominantly hydrophobic interactions located in the expanded hydrophobic pocket. The largest chemical shift changes were observed in the loop region connecting helices F and G. Inspection of available TnC sequences reveals that these residues are highly conserved, suggesting a common binding motif for the Ca2+/Mg2+-dependent interaction site in the TnC/TnI complex.

NMR analysis of cardiac troponin C-troponin I complexes: effects of phosphorylation.

Phosphorylation of the cardiac specific amino-terminus of troponin I has been demonstrated to reduce the Ca2+ affinity of the cardiac troponin C regulatory site. Recombinant N-terminal cardiac troponin I proteins, cardiac troponin I(33-80), cardiac troponin I(1-80), cardiac troponin I(1-80)DD and cardiac troponin I(1-80)pp, phosphorylated by protein kinase A, were used to form stable binary complexes with recombinant cardiac troponin C. Cardiac troponin I(1-80)DD, having phosphorylated Ser residues mutated to Asp, provided a stable mimetic of the phosphorylated state. In all complexes, the N-terminal domain of cardiac troponin I primarily makes contact with the C-terminal domain of cardiac troponin C. The nonphosphorylated cardiac specific amino-terminus, cardiac troponin I(1-80), was found to make additional interactions with the N-terminal domain of cardiac troponin C.

Ethnicity study and non-selective screening for haemoglobinopathies in the antenatal population of central Manchester.

The objective of this study was to determine the frequency of ethnic groups within the antenatal population in central Manchester and thereby ensure that the haemoglobinopathy service was targeting the correct population and their needs. Ethnic data collection records of 6718 patients were analysed over a 7 month period. Of these 62.3% stated that they were White, 13.2% Asian, 7.9% Black, 3.8% Chinese or 'other ethnic groups' and 12.7% gave no information about their ethnic background. A subset of 1144 patients were screened for haemoglobinopathies over a 1 month period. The incidence of haemoglobinopathies within the screened population was 2.62%, and comprised 0.69% beta thalassaemia trait, 1.22% sickle cell trait, 0.43% haemoglobin C trait and 0.26% haemoglobin D trait. The total incidence of haemoglobinopathies was highest within the Black population (18.2%), followed by the no information group (5.6%), Asian (3.35%) and white (0.26%). The high proportion of ethnic minorities and the significant carrier frequency in the no information group, support our view that non-selective screening should be offered to the antenatal population of central Manchester.

An evaluation of the Bio-Rad Variant Haemoglobin Testing System for the detection of haemoglobinopathies.

The Bio-Rad Variant Haemoglobin Testing System is an automated analyser which uses the principle of cation exchange high performance liquid chromatography. This evaluation was undertaken to examine the effectiveness of the instrument as a screening mechanism to assist in the diagnosis of haemoglobinopathies. The ability to quantify haemoglobins A2 and F and to 'flag' other haemoglobin variants was tested. Within-batch precision was excellent and between-batch precision was good. Linearity and sensitivity compared favourably with the manufacturer's published ranges. The level of carry-over for haemoglobins F, S and A was less than 0.25%. The mean carry-over for haemoglobin A2 was 2.08%. This higher figure reflected the smaller absolute difference between the high and low samples for this parameter. The instrument never failed to indicate the presence of an abnormal haemoglobin in 271 selected samples. The instrument was reliable throughout the evaluation and at no time was a run aborted.