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A High Purity Germanium (HPGe) detector has been used to measure the photon spectra in the majority of monoenergetic neutron fields produced at NPL (0.144, 0.250, 0.565, 2.0, 5.0 and 16.5 MeV). The HPGe was characterised and then modelled to produce a response matrix. The measured pulse height spectra were then unfolded to produce photon fluence spectra. The new spectra were used to improve the photon to neutron dose equivalent ratios from some earlier work at NPL with Geiger–Muller tubes and electronic personal dosemeters. [ABSTRACT FROM AUTHOR]

Mostly used material is concrete which has versatile quality for construction works. Fibrous concrete have significant factor that improve the scale and value to concrete for humid environments with significant role. Day by day abundant demand and use of concrete is increasing. It is considered as a 2nd largest building material due to the major productivity. By the use of fibrous concrete, some bonding and environmental issues have been addressed. Keeping in this view, an experimental based study is conducted to evaluate the strength of fiber reinforced concrete at different percentages 0%, 0.5%, 1.0%, 1.5% and 2.0%. All percentages are added by the weight of concrete with all fibers. In this connection, one hundred and fifty-three cylinders of five mixes are prepared. Workability checked of fresh concrete during the pouring of concrete cylinders. Poured cylinders' samples are left for different curing ages at 7 and 28 days. One hundred and two cylinders for compression at 7 and 28days but fifty-one cylinders for split tensile test at 28days with all fibers i.e. glass fiber, steel fiber, coconut fiber and polypropylene fiber. After curing, compression and split tensile tests are performed to check the strength of hardened concrete. Workability of five mixes lies between 40-90mm.Fibrous concrete is suitable for humid environment where high strength and voids less concrete are required. Addition of fibers in concrete may improves the strength parameters as well as to increase the bonding and tensile properties of concrete. It reduces the quantity of water to be used in concrete. Also the use of different types of fibers has been proved to be economical and is considered as environmental friendly construction material. [ABSTRACT FROM AUTHOR]

Self healing concrete are the effective methods for solving concrete deterioration and improving durability. Keeping in this view, an experimental study is conducted to evaluate the strength and healing performance of concrete made with 4% fiber for all mixes and Effective Microorganism-1 (Expounded Cracks Healing Agent) of different percentages 0%, 2%, 4% and 6%, 8% and 10%. In this connection, 108 cylinders & 54 cubes of six mixes are prepared. Workability of six mixes lies between 1mm - 38mm which is increasing by the increase of EM-1.The workability of fresh concrete using W/C ratio 0.4 is evaluated. After performing slump test, mix the all ingredients of concrete and cast the cylinders and cubes. Poured cylindrical and cubical specimens are left for different curing ages at 7, 14 and 28 days. After curing, splitting tensile strength test is performed on cylindrical specimens only and compressive strength on hardened concrete cylinders and cubes are tested and then checked the air content ratio of all six mixes which is within the acceptable ranges. After testing the cubes and cylinders are again kept in water for curing to check rate of healing and then checked the microstructure by SEM images. Cracks are small due to the use of fiber addition. By the use of EM-1, cracks can be healed. Maximum healing of crack width is between 0.04 mm to 0.07 mm if cracks width exceeds from 0.20 then it is difficult to restore. Results concluded that microorganism based self healing concrete is suitable at 6% addition in concrete which is suitable for humid environment and hydraulic structures where high strength and voids less concretes are required. Chopped strand mat can be used where concrete can be used without reinforcement. [ABSTRACT FROM AUTHOR]

Since skewness plays a vital role in different engineering phenomena, its accurate measurement gains significance. Several measures have been taken to quantify the extent of skewness in distributions over the years, but each measure is subject to some serious limitations. In this regard, the present study aims to propose a new skewness measuring functional based on distribution function evaluated at mean with minimal assumptions and limitations. Four well-recognized properties for an appropriate measure of skewness were verified and demonstrated for the new measure. A comparison was made between the new measure and the conventional moment-based measure using both functionals over the range of distributions available in the literature. Furthermore, the robustness of the proposed measure against unusual data points was explored using influence function. The mathematical findings were verified through meticulous simulation studies; further, they were verified by real data sets derived from diverse fields of inquiries. As observed, compared to the classical moment-based measure, the proposed one passed all the checks with distinction. Given the computational simplicity, applicability in a more general environment, and preservation of c-ordering of distribution, the proposed measure may be regarded as an attractive addition to the family of skewness measures. [ABSTRACT FROM AUTHOR]

The coronavirus disease (COVID-19), while mild in most cases, has nevertheless caused significant mortality. The measures adopted in most countries to contain it have led to colossal social and economic disruptions, which will impact the medium- and long-term health outcomes for many communities. In this paper, we deliberate on the reality and facts surrounding the disease. For comparison, we present data from past pandemics, some of which claimed more lives than COVID-19. Mortality data on road traffic crashes and other non-communicable diseases, which cause more deaths each year than COVID-19 has so far, is also provided. The indirect, serious health and social effects are briefly discussed. We also deliberate on how misinformation, confusion stemming from contrasting expert statements, and lack of international coordination may have influenced the public perception of the illness and increased fear and uncertainty. With pandemics and similar problems likely to re-occur, we call for evidence-based decisions, the restoration of responsible journalism and communication built on a solid scientific foundation. [ABSTRACT FROM AUTHOR]

Examined the effect of substrate temperature on the growth rate, crystal grain size, and SiO2 mask stability, in the epitaxial growth (SEG) of silicon carbide deposited from SiH4, C2H4, and HCl1 on silicon dioxide masked silicon (100). Adjustment of the composition of reactants and deposition conditions; Information on SEG; Preparation of the SiO2 masks of two thicknesses, 284 and 670 nm.

Abstract: The allelopathic water extracts (AWEs) may help improve the tolerance of crop plants against abiotic stresses owing to the presence of the secondary metabolites (i.e., allelochemicals). We conducted four independent experiments to evaluate the influence of exogenous application of AWEs (applied through seed priming or foliage spray) in improving the terminal heat and drought tolerance in bread wheat. In all the experiments, two wheat cultivars, viz. Mairaj‐2008 (drought and heat tolerant) and Faisalabad‐2008 (drought and heat sensitive), were raised in pots. Both wheat cultivars were raised under ambient conditions in the wire house till leaf boot stage (booting) by maintaining the pots at 75% water‐holding capacity (WHC). Then, managed drought and heat stresses were imposed by maintaining the pots at 35% WHC, or shifting the pots inside the glass canopies (at 75% WHC), at booting, anthesis and the grain filling stages. Drought stress reduced the grain yield of wheat by 39%–49%. Foliar application of AWEs improved the grain yield of wheat by 26%–31%, while seed priming with AWEs improved the grain yield by 18%–26%, respectively, than drought stress. Terminal heat stress reduced the grain yield of wheat by 38%. Seed priming with AWEs improved the grain yield by 21%–27%; while foliar application of AWEs improved the grain yield by 25%–29% than the heat stress treatment. In conclusion, the exogenous application of AWEs improved the stay green, accumulation of proline, soluble phenolics and glycine betaine, which helped to stabilize the biological membranes and improved the tolerance against terminal drought and heat stresses. [ABSTRACT FROM AUTHOR]

Summary: Background: An imbalance of omega (n)‐3 and n‐6 polyunsaturated fatty acids (PUFA) during critical periods of development may have adverse effects on the health of the newborn in later life. Objectives: We hypothesized that breastmilk with higher n‐6 to n‐3 PUFA ratio will have higher inflammatory cytokines and initiate cellular events similar to insulin resistance and obesity. Methods: Breastmilk was collected from healthy women who gave natural birth at full term. Breastmilk fatty acids were measured using gas chromatography; samples were pooled based on the n‐6 to n‐3 PUFA ratio (high, medium and low), and soluble cytokines were measured. Pooled samples were used to treat 3T3‐L1 cells; mRNA expression of diacylglycerol acyltransferase2, stearoyl‐CoA desaturase‐1, leptin and RPLPO was measured. Results: Breastmilk with a higher ratio of n‐6 to n‐3 PUFA showed higher pro‐inflammatory cytokines; there was a direct correlation between n‐6 PUFA and pro‐inflammatory cytokines. Breastmilk with a higher ratio of n‐6 to n‐3 PUFA increased the expression of genes involved in lipogenesis. Conclusions: Pro‐inflammatory cytokines in breastmilk are associated with higher levels of n‐6 PUFA in breastmilk and has the capacity to alter adipose tissue metabolism to likely predispose the newborn to a higher risk of obesity in later life. [ABSTRACT FROM AUTHOR]

Weeds pose a severe threat to wheat productivity in rice-wheat cropping system (RWCS). Mulching residues of allelopathic crops into soil could be one of the viable organic strategies to manage weeds and sustain productivity. A two-year field experiment was conducted to study the effect of residue mulch of allelopathic crops on the weed population in wheat. The study consisted of three allelopathic crop residue mulch (CRM) treatments (wheat, rice and sorghum) each applied at 4 t ha-1 and three nitrogen (N) sources (ammonium sulphate, calcium ammonium nitrate and urea) each applied at 125 kg N ha-1. Plastic mulch and no mulch were used as controls. Results indicated that all mulches significantly inhibited dry biomass and density of all types of weeds during both growing seasons; however, the highest inhibition of weeds was found with plastic mulch. Among allelopathic mulches, maximum suppression in dry biomass and density of narrow leaved weeds (NLWs), broad leaved weeds (BLWs) and total weeds (TWs) was found in wheat mulch followed by sorghum and rice mulch. Compared with the control (no nitrogen), nitrogen applications generally increased the growth of weeds in terms of thei dry biomass only. The highest grain harvest was recorded in plastic mulch treatments followed by sorghum and wheat mulch. Calcium ammonium nitrate exhibited higher grain yield than other nitrogen sources. A negative correlation was found for grain yield and soil water soluble phenolics with dry biomass and density of weeds. In crux, use of allelopathic CRMs may be a pragmatic approach to manage weeds, improving competitiveness of crop plants with weeds and wheat productivity. [ABSTRACT FROM AUTHOR]

Background: It is our experience that a deposition of an anesthetic solution in the ventral area of the paravertebral space near the parietal pleura and the sympathetic trunk produces extended unilateral block. Because sympathetic block effects in this extended paravertebral block are not reported yet, we undertook this singly blinded, controlled study on the sympathetic change in volunteers.Methods: A total of 22 ml 1% lidocaine was injected at the T11 level into the ventral area of the right-sided paravertebral space in 16 volunteers. The distribution of analgesia, heart rate, blood pressure and body temperature (measured by 12 skin sensors) was monitored. On a later occasion the volunteers underwent a control injection of saline.Results: Unilateral analgesia (with no contralateral element) was induced in every subject injected with lidocaine, contrasted with no block induction with saline. Loss of pin-prick sensation was observed within 10 min after injection and involved a mean of 12 (range 8-13) dermatomes. A sympathetic block was indicated by cutaneous temperature increase within at least 6 dermatomes. Increase of arterial blood pressure was obtained in all volunteers with no change in pulse rate. No side effects or complications occurred. Epidural spread of the local anesthetic was unlikely because of the absence of contralateral cutaneous analgesia and temperature increase.Conclusion: One-sided extended analgesia (sensory loss) follows the paravertebral injection of lidocaine. A large ipsilateral sympathetic block is observed without change in pulse rate and with no hypotension. These are all characteristics of an optimal regional block. [ABSTRACT FROM AUTHOR]

Aims We prospectively evaluated the effect of insulin intensification on glycaemic control and lipid levels in children and young persons with Type 1 diabetes in relation to ethnicity. Methods In the first 2 years of a 3-year observation period, as part of routine clinical care, 231 children and young persons (40% white, 28% South Asian, 32% black) from a single clinic were offered intensive insulin therapy. After 2 years, 222 were on intensive therapy and their data were compared between ethnic groups at the end of year 3. Results We observed ethnic differences in HbA1c levels during the study [study beginning and end: white children and young persons 77 and 70 mmol/mol (9.2 and 8.6%) vs. South Asian 72 and 68 mmol/mol (8.7 and 8.4%) vs. black 83 and 79 mmol/mol (9.7 and 9.4%), P-value for ANCOVA = 0.007]. By study end, South Asians had the lowest HDL cholesterol (2.0 vs. 1.4 vs. 1.6 mmol/l, P-value = 0.03) and highest triglyceride levels (0.9 vs. 1.8 vs. 1.0 mmol/l, P-value = 0.001). In linear mixed modelling, after adjustment for socio-economic deprivation and other covariates: (1) black ethnicity was associated with poorer glycaemic control ( P < 0.001) and (2) South Asian ethnicity was associated with higher triglyceride levels ( P < 0.001), independent of HbA1c. Conclusions The effect of insulin intensification on glycaemic control and lipid profile in children and young persons with Type 1 diabetes differs in relation to ethnic group. [ABSTRACT FROM AUTHOR]

The study, consisting of two independent experiments, was conducted to evaluate the role of seed priming with ascorbic acid (AsA) in drought resistance of wheat. In the first experiment, seeds of wheat cultivars Mairaj-2008 and Lasani-2008 were either soaked in aerated water (hydropriming) for 10 h or not soaked (control). In the second experiment, seeds of same wheat cultivars were soaked in aerated (2 m m) AsA solution (osmopriming) or water (hydropriming) for 10 h. In both experiments, seeds were sown in plastic pots (10 kg) maintained at 70 % and 35 % of water-holding capacity designated as well watered and drought stressed, respectively. Both experiments were laid out in a completely randomized design with six replications. Drought caused delayed and erratic emergence and disturbed the plant water relations, chlorophyll contents and membranes because of oxidative damage; however, root length in cultivar Lasani-2008 was increased under drought. Hydropriming significantly improved the seedling emergence and early growth under drought and well-watered conditions; however, improvement was substantially higher from osmopriming with AsA. Similarly, osmopriming with AsA significantly improved the leaf emergence and elongation, leaf area, specific leaf area, chlorophyll contents, root length and seedling dry weight. Owing to increase in proline accumulation, phenolics and AsA, by seed priming with AsA, plant water status was improved with simultaneous decrease in oxidative damages. These improved the leaf emergence and elongation, and shoot and root growth under drought. However, there was no difference between the cultivars in this regard. In conclusion, osmopriming with AsA improved the drought resistance of wheat owing to proline accumulation and antioxidant action of AsA and phenolics, leading to tissue water maintenance, membrane stability, and better and uniform seedling stand and growth. [ABSTRACT FROM AUTHOR]

Worldwide rice productivity is being threatened by increased endeavours of drought stress. Among the visible symptoms of drought stress, hampered water relations and disrupted cellular membrane functions are the most important. Exogenous use of polyamines (PAs), salicylic acid (SA), brassinosteroids (BRs), glycinebetaine (GB) and nitrous oxide (NO) can induce abiotic stresses tolerance in many crops. In this time course study, we appraised the comparative role of all these substances to improve the drought tolerance in rice ( Oryza sativa L.) cultivar Super-Basmati. Plants were subjected to drought stress at four leaf stage (4 weeks after emergence) by maintaining soil moisture at 50 % of field capacity. Pre-optimized concentrations of GB (150 mg l−1), SA (100 mg l−1), NO (100 μmol l−1 sodium nitroprusside as NO donor), BR (0.01 μm 24-epibrassinolide) and spermine (Spm; 10 μm) were foliar sprayed at five-leaf stage (5 weeks after emergence). There were two controls both receiving no foliar spray, viz. well watered (CK1) and drought stressed (CK2). There was substantial reduction in allometric response of rice, gas exchange and water relation attributes by drought stress. While drought stress enhanced the H2O2, malondialdehyde (MDA) and relative membrane permeability, foliar spray of all the chemicals improved growth possibly because of the improved carbon assimilation, enhanced synthesis of metabolites and maintenance of tissue water status. Simultaneous reduction in H2O2 and MDA production was also noted in the plants treated with these substances. Drought tolerance was sturdily associated with the greater tissue water potential, increased synthesis of metabolites and enhanced capacity of antioxidant system. Of all the chemicals, foliar spray with Spm was the most effective followed by BR. [ABSTRACT FROM AUTHOR]

Following spinal cord injury (SCI), the pathological sequelae which ensue through the secondary mechanisms of degeneration produce myelin deposits which are potent inhibitors of endogenous neuroregeneration. We have enhanced the immune-mediated response following a hemisection lesion by immunizing adult C57Bl/6 female mice against the inhibitor of neurite outgrowth Nogo-A(623–640) peptide. Moderate anti-Nogo-A(623–640) antibody titre levels were obtained by using Montanide as the adjuvant. However, this antibody response was not obtained using incomplete Freund's adjuvant (IFA). Significant benefit in locomotor performance was demonstrated only in animals which were vaccinated with IFA and not with Montanide. No further benefit could be demonstrated with the Nogo-A(623–640) peptide beyond that seen for adjuvant alone. These data imply that generating antibodies against Nogo-A(623–640) in vivo alone is not sufficient to enhance locomotor recovery and that subcutaneous injection of IFA prior to SCI can enhance locomotor performance. [ABSTRACT FROM AUTHOR]

Adult neural precursor cells (NPCs) in the mammalian central nervous system (CNS) have been demonstrated to be responsive to conditions of injury and disease. Here we investigated the response of NPCs in mouse models of spinal cord disease [motor neuron disease (MND)] with and without sciatic nerve axotomy, and spinal cord injury (SCI). We found that neither axotomy, nor MND alone brought about a response by Nestin-positive NPCs. However, the combination of the two resulted in mobilization of NPCs in the spinal cord. We also found that there was an increase in the number of NPCs following SCI which was further enhanced by systemic administration of the neuregulatory cytokine, leukaemia inhibitory factor (LIF). NPCs were demonstrated to differentiate into astrocytes in axotomized MND mice. However, significant differentiation into the various neural cell phenotypes was not demonstrated at 1 or 2 weeks following SCI. These data suggest that factors inherent to injury mechanisms are required for induction of an NPC response in the mammalian spinal cord. [ABSTRACT FROM AUTHOR]

There is increasing evidence that inflammatory mechanisms are involved in the pathogenesis of amyotrophic lateral sclerosis (ALS). Inhibition of a key mediator of inflammation, cyclooxygenase 2 (COX-2), represents a promising therapeutic approach in ALS. Here we tested thein vivoeffects of a specific COX-2 inhibitor, Rofecoxib, administered by intraperitoneal injection, in the SOD1G93A G1H mouse model of the familial form of ALS (fALS). Rofecoxib administration commenced at postnatal day 60 (P60), since the hallmarks of inflammation in the spinal cord were found to occur beyond this time-point in this mouse model of fALS. We found a significant but small delay in the onset of locomotor impairment in mice treated with Rofecoxib at the dose of 10 mg/kg of weight. However, survival was not effected by treatment. As prostaglandin E2 levels in spinal cord or in plasma were not reduced by Rofecoxib treatment, these results may suggest lack of sufficient bioavailability as the reason for the modest clinical changes observed. [ABSTRACT FROM AUTHOR]

Background: A significant proliferation of glial cells occurs in the spinal cord and brainstem of SOD1 G93A transgenic mice with familial amyotrophic lateral sclerosis (ALS). Since activated glia may contribute to motor neuron degeneration, we tested whether inhibition of gliosis using low-dose chemotherapy is beneficial in this mouse model. Methods: Mice were administered fortnightly intraperitoneal injections of 0.1 mg/kg vincristine (VIN) or saline commencing at postnatal day 68 before disease onset. Mice were sacrificed at end-stage disease, and spinal cords were examined for histology. Results: Survival of VIN-treated mice was significantly increased at 132.0 ± 4.1 days compared to control animals at 117.8 ± 2.1 days (p < 0.05). Furthermore, analysis of microglia and astrocyte populations suggests a reduction in the former following VIN therapy. Conclusion: This study suggests that chemotherapy may offer an alternative therapy or co-therapy for ALS. [ABSTRACT FROM AUTHOR]

Factors affecting the spread of bupivacaine in the paravertebral space were investigated in patients undergoing paravertebral nerve blocks for the treatment of chronically painful conditions. Injections of bupivacaine 0.5%, 10-15 ml mixed with depomedrone up to 80 mg were repeated at 2-wk intervals up to a maximum of four times. A blinded observer mapped out the subsequent distribution of sensory loss to cold on both sides of the torso at 5-min intervals after each injection. Age, sex, height and weight did not correlate with the block; nor did injectate volume, mass of bupivacaine, previous posterolateral thoractomy and spread of radiocontrast. Injections repeated at 2-wk intervals in the same patient resulted in different degrees of spread that were unrelated to one another. Time to peak onset of blockade was 40 min in 95% of patients. A single bolus of bupivacaine produces a safe but unpredictable block. Yet to be defined physical properties and anatomical factors are probably key determinants of the spread of bupivacaine in the paravertebral space. This single bolus technique may be better supplanted by a reversion to the older multiple level injection technique. [ABSTRACT FROM AUTHOR]

Summary Factors affecting the spread of bupivacaine in the paravertebral space were investigated in patients undergoing paravertebral nerve blocks for the treatment of chronically painful conditions. Injections of bupivacaine 0.5%, 10–15 ml mixed with depomedrone up to 80 mg were repeated at 2-wk intervals up to a maximum of four times. A blinded observer mapped out the subsequent distribution of sensory loss to cold on both sides of the torso at 5-min intervals after each injection. Age, sex, height and weight did not correlate with the block; nor did injectate volume, mass of bupivacaine, previous posterolateral thoractomy and spread of radiocontrast. Injections repeated at 2-wk intervals in the same patient resulted in different degrees of spread that were unrelated to one another. Time to peak onset of blockade was 40 min in 95% of patients. A single bolus of bupivacaine produces a safe but unpredictable block. Yet to be defined physical properties and anatomical factors are probably key determinants of the spread of bupivacaine in the paravertebral space. This single bolus technique may be better supplanted by a reversion to the older multiple level injection technique. [ABSTRACT FROM AUTHOR]

Background Laparoscopic cholecystectomy is associated with an increased conversion rate in acute cholecystitis. Aim To review the operative management of symptomatic cholelithiasis with particular reference to conversion rates and morbidity for laparoscopic cholecystectomy for acute cholecystitis. Methods Patients undergoing cholecystectomy between January 1994 and December 1998 were recruited. Demographic details, diagnosis, duration of symptoms, treatment, outcome, post-operative stay and complications were recorded. Results Complete data were available on 482 patients (84%). Laparoscopic cholecystectomy was attempted in 120 of 132 patients (91%) with acute cholecystitis and 329 of 350 patients (94%) with non-acute gallbladder disease. Conversion rates were 27% (33/120) and 6.7% (22/329) for acute and non-acute gallbladder disease, respectively (p<0.001 x2 test). Relating the interval from onset of symptoms to surgery, conversion rates for acute cholecystitis were: <3 days, 5/17 (29%); 4 to 42 days, 14/59 (23%) and >42 days, 14/44 (31%). There were three bile duct injuries, two in the delayed (>45 days) acute group and one in the non-acute group. Conclusion Early laparoscopic cholecystectomy is the treatment of choice for acute cholecystitis, but is associated with a high conversion rate independent of the timing of surgery. [ABSTRACT FROM AUTHOR]

All 38 patients listed for day-case spinal endoscopy over a 12-month period (April 1998 - April 1999), who had chronic severe low back pain with a radiculopathic element, were studied prospectively. The mean [range] pain duration before treatment was 10.9 [2-26] years and 50% had failed back surgery syndrome. In all patients in whom treatment was completed (n = 34), the pain-generating nerve roots were located through symptom interaction with the patient. All had epidural scar tissue, 14 (41%) having dense adhesions. Mobilisation of adhesions around the nerve root (neuroplasty) was performed so that a pocket was formed for the subsequent placement of bupivacaine, Depomedrone and clonidine. No intra-operative complications occurred and side-effects were minimal. Follow-up over a 12-month period showed statistically significant reductions in pain scores and disability. Spinal endoscopy may be the diagnostic method of choice for epidural fibrosis. It has substantial therapeutic and research potential. Prospective randomised studies are required. [ABSTRACT FROM AUTHOR]

All 38 patients listed for day-case spinal endoscopy over a 12-month period (April 1998 – April 1999), who had chronic severe low back pain with a radiculopathic element, were studied prospectively. The mean [range] pain duration before treatment was 10.9 [2–26] years and 50% had failed back surgery syndrome. In all patients in whom treatment was completed (n = 34), the pain-generating nerve roots were located through symptom interaction with the patient. All had epidural scar tissue, 14 (41%) having dense adhesions. Mobilisation of adhesions around the nerve root (neuroplasty) was performed so that a pocket was formed for the subsequent placement of bupivacaine, Depomedrone and clonidine. No intra-operative complications occurred and side-effects were minimal. Follow-up over a 12-month period showed statistically significant reductions in pain scores and disability. Spinal endoscopy may be the diagnostic method of choice for epidural fibrosis. It has substantial therapeutic and research potential. Prospective randomised studies are required. [ABSTRACT FROM AUTHOR]

The 75-kDa low-affinity neurotrophin receptor (p75NTR) has been shown in previous reports to mediate neuronal cell death in vitro and in vivo under certain circumstances. Antisense oligonucleotides directed against p75NTR promote the survival of nerve growth factor-deprived dorsal root ganglia sensory neurons in vitro (Barrett, G.; Bartlett, P., Proc. Natl. Acad. Sci. USA 91:6501–6505; 1994) and axotomized dorsal root ganglia sensory neurons in vivo (Cheema, S. S.; Barrett, G. L.; Bartlett, P. F., J. Neurosci. Res. 46:239–245; 1996). In this study we compared the neuroprotective effects of antisense p75NTR oligonucleotides with two neurotrophic factors, namely nerve growth factor (NGF) and leukemia inhibitory factor, on cultured sensory neurons derived from postnatal day 7 and 14 rat dorsal root ganglia. After 3 d in culture, treatment with the neurotrophic factors had significant survival effects on sensory neuron cultures compared to treatment with basal medium (control). However, after 6 and 9 d in culture these rescue effects were not apparent. In contrast, antisense p75NTR oligonucleotides rescued significantly higher numbers of dorsal root ganglia sensory neurons after 6 and 9 d in culture than treatment with neurotrophic factors, sense oligonucleotides, and basal medium. Furthermore, antisense p75NTR oligonucleotides rescued trkA-, B-, and C-expressing neurons, while NGF and leukemia inhibitory factor targeted primarily the trkA-positive neurons. These findings suggest that antisense-based strategies that inhibit gene expression of cytotoxic molecules are more efficient at preventing postnatal sensory neuronal death in vitro than treatment with individual neurotrophic factors. [ABSTRACT FROM AUTHOR]

This study was designed to determine the level of inhibition of gene transcription by the reduction in insulin levels upon the onset of diabetes in spontaneously diabetic B/B rats and if reducing the level of polyunsaturated fatty acids (PUFA) in the diet will increase lipogenic enzyme activity. Control (eight animals per group) and spontaneously diabetic B/B male weanling rats (25 animals per group) were fed semipurified diets containing 20% (w/w) fat of either low (0.25) or high (1.0) polyunsaturated to saturated (P/S) fatty acid ratio. Rats were killed at the onset of diabetes [blood glucose level of ≅100 mg/dL (5.55 mM)] and as they became highly diabetic [blood glucose level of ≅400 mg/dL (22.22 mM)]. Total RNA was extracted from liver, and the relative amount of mRNA coding for fatty acid synthase (FAS), acetyl-CoA carboxylase, malic enzyme, pyruvate kinase, and phosphoenolpyruvate carboxykinase was determined. Liver enzyme activities were also measured. The mRNA levels for FAS, acetyl-CoA carboxylase, and malic enzyme decreased compared to control animals. The mRNA level for pyruvate kinase decreased at the onset of diabetes as compared to control animals. Feeding animals the low P/S diet treatment elevated the level of mRNA and lipogenic enzyme activity compared to animals fed the high P/S diet treatment, suggesting that the effect of PUFA on lipogenic enzymes is through a direct effect on gene expression. [ABSTRACT FROM AUTHOR]

We examined whether the degree of saturation of C-18 fatty acids influenced hepatic cholesterol metabolism in C3H mice. The mice were fed diets containing 20 g/100 g fat, enriched in stearic (18:0), oleic (18:1) or linoleic acid (18:2) with or without 1 g/100 g cholesterol. Plasma total cholesterol concentration was lower in mice fed the 18:0 diet relative to those fed the 18:1- or 18:2-enriched diets (P < 0.05) regardless of dietary cholesterol supplementation. Dietary cholesterol significantly raised hepatic total cholesterol concentration (P < 0.05) in those fed the 18:1- and 18:2-enriched diets, but not in mice fed the 18:0-enriched diet. Dietary cholesterol raised biliary cholesterol concentration (P < 0. 05) in mice fed the 18:1- and 18:2-enriched diets, but not in mice fed the 18:0-enriched diet. The cholesterol saturation index was variably affected by the fat diets. Feeding diets containing cholesterol suppressed the hepatic 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) activity and induced acyl coenzyme A:cholesterol acyl transferase (ACAT) activity compared with feeding diets without cholesterol (P < 0.05), indicating that the liver was exposed to dietary cholesterol. Hepatic ACAT activity was lower in mice fed the 18:0-enriched diet compared with those fed the 18:1- or 18:2-enriched diets (P < 0.05). Addition of cholesterol to the 18:1 diet induced the largest increase of hepatic ACAT activity, and this was associated with the enrichment of VLDL with cholesterol. Varying the degree of saturation of C-18 fatty acids influences the metabolism and disposition of hepatic cholesterol. [ABSTRACT FROM AUTHOR]

An occluded internal carotid artery (ICA) is considered a “safe artery” as it causes few symptoms. However, it has recently been suggested that spontaneous recanalisation of ICA occlusions may occur. To determine the incidence of ICA recanalisation among patients with a previously documented occluded ICA. Patients with a documented ICA occlusion between September 2001 and January 2003 were identified. Patients who consented to participate had carotid duplex scans performed. Demographic and clinical data were collected. Statistical analyses were performed as appropriate. The total number of carotid duplex scans performed during the original study period was 719. An occluded ICA was identified in 30 (4.2%) patients. Of 19 patients who were rescanned two (11%) had recanalised a previously occluded ICA. Recanalisation occurs in a small number of patients who may need long-term surveillance. [ABSTRACT FROM AUTHOR]