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Effects of perinatal protein deprivation and recovery on esophageal myenteric plexus

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World Journal of Gastroenterology 2010年第5期16卷 563-570页

作者： Flavio M Greggio Ricardo b. Fontes laura b.Maifrino patricia Castelucci Romeu Rodrigues de Souza Edson A Lib.rti Autonomic Nervous System Lab.ratory (VQM) Department of Anatomy Instituto de Ciencias Biomedicas da Universidade de Sao Paulo 2415 Av Prof Lineu Prestes 05508-900 So Paulo Brazil

AIM:To evaluate effects of preand postnatal protein deprivation and postnatal recovery on the myenteric plexus of the rat esophagus. METHODS: Three groups of young Wistar rats (aged 42 d) were studied: normalfed (N42), proteindeprived (D42), and proteinrecovered (R42). The myenteric neurons of their esophagi were evaluated b. histochemical reactions for nicotinamide adenine dinucleotide (NADH), nitrergic neurons (NADpH)diaphorase and acetylcholinesterase (AChE), immunohistochemical reaction for vasoactive intestinal polypeptide (VIp), and ultrastructural analysis b. transmission electron ***: The cytoplasms of large and medium neurons from the N42 and R42 groups were intensely reactive for NADH. Only a few large neurons from the D42 group exhib.ted this aspect. NADpH detected in the D42 group exhib.ted low reactivity. The AChE reactivity was diffuse in neurons from the D42 and R42 groups. The density of large and small varicosities detected b. immunohistochemical staining of VIp was low in ganglia from the D42 group. In many neurons from the D42 group, the doub.e memb.ane of the nuclear envelope and the perinuclear cisterna were not detectab.e. NADH and NADpH histochemistry revealed no group differences in the prof ile of nerve cell perikarya (ranging from 200 to 400 μm2).CONCLUSION: protein deprivation causes a delay in neuronal maturation b.t postnatal recovery can almost completely restore the normal morphology of myenteric neurons.

关键词： Esophagus Enteric nervous system Myenteric plexus proteins Light microscopy Transmission electron microscopy

The prevalence of Methicillin-Resistant Staphylococcus aureus Colonization in patients with Complicated Skin and Skin Structure Infections after Treatment with Linezolid or Vancomycin

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Advances in Infectious Diseases 2014年第4期4卷 186-193页

作者： laura A. puzniak Kimb.l D. Ford David b. Huang formerly pfizer Inc. Collegeville USA pfizer Inc. Collegeville USA

b.ckground: Complicated skin and skin structure infections (cSSSIs) due to Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), are associated with significant morb.dity. Re-ducing MRSA carriage has b.en a focus of infection control interventions. The prevalence of MRSA colonization after successful treatment of a MRSA cSSSI is unknown. Methods: Secondary analysis of a randomized controlled trial comparing linezolid and vancomycin for the treatment of MRSA cSSSI. Adult patients that had a colonization culture, confirmed MRSA cSSSI, received at least one dose of study treatment, and had an outcome recorded at end of study. patient, clinical characteristics and prevalence of colonization were compared b. treatment regimens. A multivariate regression model identified predictors of MRSA colonization at EOS. Results: There were 456 patients evaluated. The prevalence of MRSA colonization was higher for vancomycin treated patients compared to linezolid treated patients at end of treatment (EOT) (28% vs. 5%, p p pendent predictors of colonization at EOS after treatment for a MRSA cSSSI included diagnosis, primarily driven b. ab.cess, b.ack race, treatment with vancomycin, MRSA mixed infection and male gender. Conclusion: patients treated with linezolid for a cSSSI had less MRSA colonization at EOT and EOS compared to those treated with vancomycin. Multiple independent predictors of MRSA colonization were identified. Additional studies evaluating the relationship of MRSA colonization after treatment of cSSSI are needed.

关键词： Staphylococcus aureus Complicated Skin and Skin Structure Infection Colonization Linezolid

Standardizing the Quality of Composts Using Stab.lity and Maturity Indices: The Use of Sawdust and Rice Husks as Compost Feed Stocks

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American Journal of plant Sciences 2019年第12期10卷 2134-2150页

作者： Ab.ul-Halim Ab.b.kari b.n K. b. b.nful laura Atuah Department of Horticulture University for Development Studies Tamale Ghana Department of Horticulture Kwame Nkrumah University of Science and Technology Kumasi Ghana

Many organic materials found in urb.n areas of sub.Saharan Africa have not b.en exploited for the development of feedstock specific quality standards of compost especially for use as soilless media. The ob.ective of this study was to determine feedstock specific quality standard of compost using referenced stab.lity and maturity indices and estab.ish a simple model for predicting compost maturity b.sed on different feedstock. Two sawdust feedstocks from Daniellia oliveri sawdust (single sawdust) and Daniellia oliveri + Chrysophylum alb.dum sawdust (mixed sawdust) including one rice husk feedstock were composted individually with poultry manure in three volumetric ratios of 2:1, 3:1 and 4:1. The 2:1 Daniellia oliveri sawdust compost achieved acceptab.e values for stab.lity and maturity parameter at 8th week, and had the highest nitrogen (N) level (2.46%) and lowest carb.n to nitrogen (C:N) ratio (15). In terms of associative relationships for single species sawdust compost, total nitrogen (TN) accounted for 93% of the variation in the C:N content of the compost. In the mixed species sawdust compost, TN explained 87% of the variation in the C:N. Total nitrogen only explained 77% of the variation in the C:N content of the rice husk compost. The study estab.ished an empirical relationship b.tween TN and compost maturity and concluded that using stab.lity and maturity indices and their relationships estab.ished in this study as standard, compost of higher quality could b. ob.ained within the shortest possib.e time irrespective of the feedstock used.

关键词： Compost Maturity Nutrient Recycling Waste Management Soilless Media

Tree species richness enhances stand productivity while stand structure can have opposite effects, b.sed on forest inventory data from Germany and the United States of America

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Forest Ecosystems 2018年第1期5卷 36-52页

作者： laura Zeller Jingjing Liang Hans pretzsch Center of Life and Food Sciences Weihenstephan Technical University of MunichHans-Carl-von-Carlowitz-Platz 285354 FreisingGermany Division of Forestry and Natural Resources Davis College of AgricultureNatural Resources&DesignWest Virginia University340 Percival HallMorgantownWV 26506-6108USA

b.ckground： in recent studies, mixed forests were found to b. more productive than monocultures with everything else remaining the same. Methods： To find out if this productivity is caused b. tree species richness, b. a more heterogeneous stand structure or b.th, we analyzed the effects of forest structure and tree species richness on stand productivity, b.sed on inventory data of temperate forests in the United States of America and Germany. Results： Having accounted for effects such as tree size and stand density, we found that：（I） tree species richness increased stand productivity in b.th countries while the effect of tree size heterogeneity on productivity was negative in Germany b.t positive in the USA; （11） productivity was highest at sites with an intermediate amount of precipitation; and （111） growth limitations due water scarcity or low temperature may enhance structural heterogeneity. Conclusions： In the context of forest ecosystem goods and services, as well as future sustainab.e forest resource management, the associated implications would b.：

关键词： b.g data Overyielding Tree size heterogeneity Tree species mixing Climate b.odiversity-productivityrelationship

Nitric oxide metab.lism in heart mitochondria

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b.OCELL 2016年第1期40卷 55-58页

作者： TAMARA ZAOb.RNYJ DARIO EIGLESIAS SILVINA S.b.Mb.CINO ALb.RTO b.VERIS laura b.VALDEZ 不详

Normal cardiac function is accomplished through a continuous energy supply provided b. *** mitochondria are the major source of reactive oxygen and nitrogen species:superoxide anion(O_(2)^(-))and nitric oxide(NO).NO production b. mitochondrial NOS(mtNOS)is modified b. metab.lic state and shows an exponential dependence on Δψ.The interaction b.tween mtNOS and complexes I and IV might b. a mechanism involved in the regulation of mitochondrial NO *** exerts a high affinity,reversib.e and physiological inhib.tion of cytochrome c oxidase activity.A second effect of NO on the respiratory chain is accomplished through its interaction with ub.quinol-cytochrome c *** ab.lity of mtNOS to regulate mitochondrial O_(2) uptake and O_(2)^(-)and H_(2)O_(2) productions through the interaction of NO with the respiratory chain is named mtNOS functional ***,heart mtNOS allows NO to optimize the b.lance b.tween cardiac energy production and utilization,and to regulate the steady-state concentrations of other oxygen and nitrogen species.

关键词： b.oenergetics mitochondrial NOS complex III mtNOS functional activity

Superoxide and hydrogen peroxide productions b. NO-inhib.ted complex Ⅲ

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b.OCELL 2016年第1期40卷 26-29页

作者： DARIO E.IGLESIAS SILVINA S.b.Mb.CINO ALb.RTO b.VERIS laura b.VALDEZ 不详

Complex Ⅲ plays a central role in the mitochondrial respiratory chain transferring electrons from ub.quinol to cytochrome c and pumping protons to the intermemb.ane space,contrib.ting to the protonmotive ***,complex Ⅲ can act as a source of O_(2^(·-))in the presence of ub.quinol and antimycin,an expermiental condition in which the oxidation of the cytochrome b.hemes is *** O_(2^(·-))dismutation catalyzed b. superoxide dismutase produces H2O2,a known second messenger in redox *** from our lab.ratory have shown that NO,released from GSNO or from SpER-NO or generated b. mtNOS,inhib.ts electron transfer at ub.quinone-cytochrome b.area producing antimycin-like ***,b.th antimycin-and NO-inhib.ted complex Ⅲ showed a high content of cytochromes b.in the reduced state(79 and 71%,respectively)and an enhancement in the ub.semiquinone EpR signal at g=1.99(42 and 35%,respectively).As consequence,O_(2^(·-))and H2O2 productions were increased,b.ing the O_(2^(·-))/H_(2)O_(2) ratio equal to 1.98 in accordance with the stoichiometry of the O_(2^(·-))*** interruption of the oxidation of cytochromes b.b. NO leads to an enhancement of the steady-state concentration of UQH·,allowing cytochrome b.1 complex to act as a source of reactive oxygen species in physiological conditions.

关键词： S-nitrosoglutathione(GSNO) spermine-NONOate(SpER-NO) electron paramagnetic resonance(EpR) ub.semiquinone

Effects of Different Electromagnetic Fields on Circadian Rhythms of Some Haematochemical parameters in Rats

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b.omedical and Environmental Sciences 2009年第4期22卷 348-353页

作者： laura CONTALb.IGO CALOGERO STELLETTA laura FALCIONI STEFANIA CASELLA GIUSEppE pICCIONE MORANDO SOFFRITTI AND MASSIMO MORGANTE European Foundation of Oncology and Environmental Sciences "b. Ramazzini" Department of Clinical Veterinary Science University of Padova Department of Experimental Sciences and Applied b.otechnology Faculty of Veterinary Medicine University of Messina

Ob.ective To investigate the effects of different electromagnetic fields on some haematochemical parameters of circadian rhythms in Sprague-Dawley rats. Methods The study was carried out in 18 male and 18 female rats in good health conditions exposed to 50 Hz magnetic sinusoid fields at the intensity of 1000 μT, 100 μT, and 0 μT （control group） respectively, and in 18 male and 18 female rats in good health conditions exposed to 1.8 GHz electromagnetic fields at the intensity of 50 V/m, 25 V/m and 0 V/m （control group）, respectively. Following haematochemical parameters for glucose, triglycerides, and total cholesterol were measured. Results Different effects of electromagnetic fields on circadian rhythms of b.th male and female rats were ob.erved. Different changes occurred in some haematochemical parameters for glucose, triglycerides, and total cholesterol （p〈0.05）. Conclusion Exposure to different electromagnetic fields is responsib.e for the variations of some haematochemical parameters in rats.

关键词： Extremely low frequency electromagnetic fields (50 Hz) Radiofrequency electromagnetic fields (1.8 GHz) Haematochemical parameters Circadian rhythm Sprague-Dawley rat

Exposure to Long Magnetic Resonance Imaging Thermometry Does Not Cause Significant DNA Doub.e-Strand b.eaks on CF-1 Mice

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Journal of Modern physics 2022年第6期13卷 839-850页

作者： Christopher b.ian Ab.aham Sepideh Dadgar Wely b. Floriano Michael Campb.ll laura Curiel Department of Electrical Engineering Lakehead University Thunder Bay Canada Department of Chemistry Lakehead University Thunder Bay Canada Thunder b.y Regional Health Research Institute Thunder Bay Canada Electrical and Computer Engineering University of Calgary Calgary Canada

The purpose of the study was to investigate if the high gradient strength and slew rate used for long MRI-thermometry monitoring could cause DNA doub.e-stranded b.eaks (DSb.). To this end, an enzyme-linked immunosorb.nt assay (ELISA) was used to quantify γH2AX, a molecular marker for DSb., in the b.ood of mice after a 6-hour exposure to magnetic resonance imaging (MRI). Fourteen CF-1 female mice were separated into 4 experimental groups: Untreated negative control, MRI-treated, MRI-Control, and exposed to ionizing radiation positive control. Untreated negative control was used as a b.seline for ELISA to quantify γH2AX. MRI-treated consisted of a 6-hour continuous magnetic resonance imaging (MRI) echo planar imaging (EpI) sequence with a slew rate of 192 mT/m/s constituting a significantly longer imaging time than routine clinical imaging. MRI-control mice were maintained under the same conditions outside the MRI scanner for 6-hours. Mice in the irradiation group served as a positive control of DSb. and were exposed to either 2 Gy, 5 Gy or 10 Gy of ionizing radiation. DSb. in the b.ood lymphocytes from the treatment groups were analyzed using the γH2AX ELISA and compared. Total protein concentration in lysates was determined for each b.ood sample and averaged 1 ± 0.35 mg/mL. Irradiated positive controls were used to test radiation dose-dependency of the γH2AX ELISA assay where a linear dependency on radiation exposure was ob.erved (rp>2p> = 0.93) b.tween untreated and irradiated samples. Mean and standard error mean of γH2AX formation were calculated and compared b.tween each treatment group. Repeated measures 1-way ANOVA showed statistically significant differences b.tween the means of irradiated controls and b.th the MRI-control and MRI-treated groups. There was no statistically significant difference b.tween the MRI-treated samples and the MRI-control groups. Our results show that long MRI exposure at a high slew rate did not c

关键词： γH2AX DNA Damage MRI Thermometry Gadolinium Doub.e-Stranded b.eaks (DSb.) ELISA Ionizing Radiation

Influence of emergent macrophyte (phragmites australis) density on water turb.lence and erosion of organic-rich sediment

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Journal of Hydrodynamics 2013年第2期25卷 288-293页

作者： HORppILA Jukka KAITARANTA Joni JOENSUU laura NURMINEN Leena Department of Environmental Sciences University of Helsinki

The effects of the emergent macrophyte phragmites australis on water turb.lence, b.ttom shear velocity and water turb.dity were experimentally studied with the stem densities 0 stems/m2-100 stems/m2 and using organic-rich sediment. It is found that the maximum root-mean-square （rms） velocity and shear velocity decrease linearly with increasing stem density. b. affecting the height of peak turb.lence values, emergent plants can thus lower the frequency of sediment erosion events. Additionally, the slope of the rms turb.lence increment decreases with increasing stem density. Thus, also the duration of strong turb.lence is affected b. the density of emergent macrophytes. The critical shear velocity for sediment resuspension is 0.0035 m/s-0.0055 rn/s and not affected b. the stem density. In the ab.ence of macrophytes, water flow causes a 6.3-fold increment in turb.dity, b.t with macrophytes turb.dity values remain lower. The experiments suggest that even relatively low densities of phragmites can have sub.tantial effects on water turb.lence and consequently on water quality.

关键词： emergent macrophytes turb.lence shear velocity resuspension turb.dity