The Double Projecting Neuron of the Cat Spinal Dorsal Horn——A Study with Double Retrograde Fluorescent Tracing Technique

The new double projecting neurons were found in the cat spinal dorsal horn by the double retrograde fluorescent tracing technique.Fast Blue(FB)was injected into unilateral dorsal column nucleus(DCN)of adult cats anesthetized with pentobarbital.Nuclear Yellow(NY)was injected ipsilaterally into the lateral cervical nucleus(LCN)8-9 days later.After an additional 18-30 hrs.

BINDING OF IONIC SURFACTANTS ON OPPOSITELY CHARGED POLYELECTROLYTES OBSERVED BY FLUORESCENCE METHODS

Our recent studies concerning the binding of ionic surfactants on oppositely charged polyelectrolytes observedwith fluorescence techniques are reviewed. The cationic surfactants cetyltrimethylammonium bromide (CTAB),dodecyltrimethylammonium chloride (DTAC), and nonionic surfactant octaethylene glycol monododecyl ether (C_(12)E_8) wereallowed to bind on anionic poly(2-acrylamido-2-methylpropanesulfonic acid) (PAMPS) and its pyrene and/or naphthalenelabeled copolymers. The relative excimer emission intensity I_E/I_M of a cationic probe l-pyrenemethylamine hydrochloride(PyMeA·HCl) and the non-radiative energy transfer (NRET) I_(Py)/I_(Np) of naphthalene to pyrene for labeled polyelectrolyteswere chosen to monitor the binding process and the conformation change of surfactant-bound polyelectrolytes. The 1:1aggregation of polyelectrolyte-CTAB with respect to the charge was found as long as the CTAB concentration was slightlyhigher than its critical aggregation concentration (CAC). The intermolecular NRET indicated that the CTAB-boundpolyelectrolytes aggregated together through the hydrophobic interaction between the CTAB tails. However, neither 1:1polyelectrolyte-DTAC aggregation nor intermolecular aggregation of DTAC-bound polyelectrolyte was observed owing to itsweaker hydrophobicity of 12 carbon atoms in the tail, which is shorter than that of CTAB. As known from the fluorescenceresults, nonionic surfactant C_(12)E_8 did not bind on the anionic polyelectrolytes, but the presence of PAMPS promoted themicelle formation for C_(12)E_8 at the CAC slightly below its critical micelle concentration (CMC). The solid complex of dansyllabeled AMPS copolymer-surfactant exhibited a decrease in local polarity with increasing charge density of thepolyelectrolyte or with alkane tail length of the surfactant. SAXS suggested a lamella structure for the AMPS copolymer-surfactant solid complexes with a long period of 3.87 nm for CTAB and 3.04 nm for DTAC, respectively.

EXPERIMENTAL INVESTIGATION ON THE CHAOTIC PHENOMENA IN THE WAKE OF A NATURAL THERMAL CONVECTION FLOW

Chaotic phenomena in the wake of thermal convection flow fields above a heating flat plate were investigated experimentally. A newly developed electron beam fluorescence technique (EBF) was used to simultaneously measure density fluctuation at 7 points in a cross section above the plate. Correlation dimensions, intermittence coefficients, Fourier spectrum have been obtained for different Grashof numbers. Spatial distribution of correlation dimensions are presented. The experimental result shows that there is a certain relationship between the density fluctuation and the Gr number. And time-spacial characteristic of chaos evolution is also given.

Fluoro-ruby retrograde tracing and three-dimensional visualization of the corticospinal tract in the guinea pig

Fluoro-ruby was injected into the posterior funiculus of the spinal cord in the cervical （C5-T2） and lumbar （L3-6） segments of adult guinea pigs. The spinal cord was cut into serial frozen sections. The Fluoro-ruby labeling was clearly delineated from the surrounding structure. The labeling traversed the cervical, thoracic and lumbar segments, and was located on the ventral portion of the posterior funiculus on the injected side, proximal to the intermediate zone of the dorsal gray matter. The fluorescence area narrowed rostro-caudally. The spinal cord, spinal cord gray matter and corticospinal tract were reconstructed using 3D-DOCTOR 4.0 software, resulting in a robust three-dimensional profile. Using functionality provided by the reconstruction software, free multi-angle observation and sectioning could be conducted on the spinal cord and corticospinal tract. Our experimental findings indicate that the Fluoro-ruby retrograde fluorescent tracing technique can accurately display the anatomical location of corticospinal tract in the guinea pig and that three-dimensional reconstruction software can be used to provide a three-dimensional image of the corticospinal tract.

Diagnosis,fetal risk and treatment of pemphigoid gestationis in pregnancy:A case report

BACKGROUND Pemphigoid gestationis(PG)is a rare autoimmune blistering disease that usually presents in the second or third trimester,with an incidence of 1 per 50000 pregnancies.PG tends to recur with an earlier onset and a more severe course in subsequent pregnancies.Skin biopsy markers can be confirmed by direct immunofluorescence staining.CASE SUMMARY Our patient was diagnosed with PG at 8 mo of gestation with fresh bullous lesion marks on the abdomen and limbs.Termination of the pregnancy was performed by cesarean section at 37+4 wk of gestation.The patient delivered an infant weighing 3620 gm.The infant had urticaria-like and vesicular skin lesions and was diagnosed with PG.The patient was discharged on prednisolone and in a satisfactory condition.The infant was discharged after anti-inflammatory therapy for one week.CONCLUSION PG is a rarely reported disease,and 10%of newborns develop mild clinical symptoms consisting of urticaria-like or vesicular skin lesions.We intend to remind clinicians to consider this condition when a patient presents with such lesions so that treatment can be started early and neonatal morbidity can be taken into account.

Preconditioning crush increases the survival rate of motor neurons after spinal root avulsion

In a previous study, heat shock protein 27 was persistently upregulated in ventral motor neurons following nerve root avulsion or crush. Here, we examined whether the upregulation of heat shock protein 27 would increase the survival rate of motor neurons. Rats were divided into two groups： an avulsion-only group （avtflsion of the L4 lumbar nerve root only） and a crush-avulsion group （the L4 lumbar nerve root was crushed 1 week prior to the avulsion）. Immunofluores- cent staining revealed that the survival rate of motor neurons was significantly greater in the crush-avulsion group than in the avulsion-only group, and this difference remained for at least 5 weeks after avulsion. The higher neuronal survival rate may be explained by the upregulation of heat shock protein 27 expression in motor neurons in the crush-avulsion group. Further- more, preconditioning crush greatly attenuated the expression of nitric oxide synthase in the motor neurons. Our findings indicate that the neuroprotective action of preconditioning crush is mediated through the upregulation of heat shock protein 27 expression and the attenuation of neuronal nitric oxide synthase upregulation following avulsion.

Optimum conditions and application of one-step fluorescent cyanoacrylate fuming method for fingermark development based on PolyCyano UV

Cyanoacrylate fluorescent staining has become a common method for developing latent fingermarks on light-coloured or white objects.The method requires two steps and skilled operation,and the handling process has the risk of damaging the ridge details or even biological samples.To take full advantage of the high-sensitivity fluorescence,recent research efforts on fluorescent cyanoacrylate have aimed to avoid rinsing after staining,add fluorescence to the cyanoacrylate,increase the fluorescence intensity and broaden the fluorescence spectral range.PolyCyano UV is a novel product that can be used to overcome the disadvantages associated with progressing to one-step fuming to directly develop fingermarks.To explore the optimal development conditions and application effects of PolyCyano UV,thermogravimetric differential thermal analysis,fluorescence spectroscopy and control variable analysis are used to determine and analyse the best conditions for using the reagent,including temperature,fluorescence excitation band,relative humidity and fuming concentration.The temperature range of the one-step fuming development method is 212.14℃–275.16℃,the wavelength range of the excitation light source is 235–580 nm,the relative humidity is 60%–80%,the concentration of the fume is 1–3g/m^(3) and the specific value is related to the surface properties of the object and the aged time of the fingermarks.Additionally,fluorescence spectroscopy shows that the excitation wavelength range of the light source is 235–580nm.Based on the best fuming condition,many common objects were selected to proceed to the application experiments,which allowed for a comparison with the traditional visualisation method,namely the Cyanobloom reagent+dyeing two-step development method.The comparison showed that latent fingermarks on most non-porous smooth surfaces,especially on light-coloured or white objects,were developed successfully.In addition,a comparative study with the conventional cyanoacrylate glue–fluorescent staining experiments showed that the effect of dyeing afterwards with Rhodamine 6G is better than the one-step method.The effect of dyeing with BBD is basically the same as that of the one-step method.

Interactions between metal ions and the biopolymer in activated sludge： quantification and effects of system pH value

The quantification and effects of system pH value on the interactions between Pb（II） and the biopolymer in activated sludge were investigated. The biopolymer had two protein-like fluorescence peaks （Ex/Em = 280 nm1326-338 nm for peak A; Ex/Em = 220-230 nm/324-338 nm for peak B）. The fluorescence intensities of peak B were higher than those of peak A. The fluorophores of both peaks could be largely quenched by Pb（ll）, and the quencher dose for peak B was about half of that for peak A. The modified Stern-Volmer equation well depicted the fluorescence quenching titration. The quenching constant （Ka） values for both peaks decreased with rising system pH value, and then sharply decreased under alkaline conditions. It could be attributed to that the alkaline conditions caused the reduction of available Pb（II） due to the occurrence of Pb（OH）2 sediments. The Ka values of peak B were bigger than those for peak A at the same system pH values. Accordingly, the aromatic proteins （peak B） played a key role in the interactions between metal ions and the biopolymer.

Differences in hydrocarbon composition of shale oils in different phase states from the Qingshankou Formation, Songliao Basin, as determined from fluorescence experiments

The phase state of shale oil has a significant impact on its mobility.The mineral and organic matter in shale reservoirs play an important role in oil phase.This study attempts to evaluate the properties of shale oils in different phase states and to investigate how these differences are related to initial shale composition.Samples from the first member of the Qingshankou(Q1)Formation were analyzed using X-ray diffraction,total organic carbon content,rock pyrolysis solvent extraction and group component separation.Subsequently,fluorescence techniques were used to quantitatively determine the content and properties of the free oil(FO),the adsorbed oil associated with carbonate(ACO),and the adsorbed oil associated with silicate and clay-organic complexes(AKO).The results showed that non-hydrocarbons and asphaltenes are the primary fluorescing compounds on shale grain.FO is the dominant phase in the Q1 Formation.The quantitative grain fluorescence on extraction(QGF-E)and total scanning fluorescence(TSF)spectra of ACO and AKO show a significant redshift compared to the FO.The TSF spectra of FO have a characteristic skew to the left and a single peak distribution,suggesting a relatively light hydrocarbon component.The TSF spectra of ACO show a skew to the right and an even,double-peaked distribution.The TSF spectra of AKO show a single peak with a skew to the right,indicating that ACO and AKO hydrocarbons are heavier than FO hydrocarbons.In summary,enrichment of carbonate minerals in shale may result in mis-identification of“sweet spots”when using QGF.The normalized fluorescence intensity of QGF-E and TSF are effective indexes allowing oil content evaluation.As an additional complicating factor,hydrocarbon fractionation occurs during generation and expulsion,leading to a differentiation of oil composition.And FO has high relatively light hydrocarbon content and the strongest fluidity.

Interaction between retanning agents and wet white tanned by a novel bimetal complex tanning agent

A promising and practical chrome-free tanning system has been developed based on a novel Al–Zr bimetal complex tanning agent.However,to achieve satisfactory resultant leather,the retanning process that is compatible with this emerging tannage needs to be investigated systematically.This paper aims to explore the interaction between the bimetal complex tanned wet white and retanning agents.The isoelectric point(pI)of wet white was 7.2,which was nearly the same as wet blue.The electropositivity of wet white was even higher than that of wet blue during post-tanning processes,resulting in higher uptake rate of retanning agents.The distribution of various retanning agents in wet white was analyzed by pI measurement of layered leather and fluorescent tracing technique.The retanning agents were unevenly distributed throughout the cross-section,which might be an important restriction factor in obtaining satisfactory organoleptic properties of the crust leather.This fact is mainly due to the strong electrostatic interaction between anionic retanning agents and wet white.Applying a high dosage of multiple retanning agents in a proper sequence of addition benefited the full penetration of retanning agents in leather matrix and thus improved the organoleptic properties of crust leather.This work provides guidance for optimizing retanning process of the wet white leather.

Monitoring the Aggregation of Dansyl Chloride in Acetone through Fluorescence Measurements

The aggregation of dansyl chloride (DNS-Cl) in acetone has been studied indetail by steady-state fluorescence techniques. It has been demonstrated that DNS-Cl is stable inacetone during purification and aggregation study processes. The aggregates are not solvolyzed inacetone, and do not take part in any chemical reactions either. It has been found that DNS-Cl tendsto aggregate even when its concentration is much lower than its solubility in acetone. Theaggregation is reversible, and both the aggregation and the deaggregation are very slow processes.Introduction of SDS has a positive effect upon the formation and stabilization of the aggregates.

Detection of Epstein-Barr virus infection subtype in patients with multiple sclerosis by indirect immunofluorescence assay

Aim:The aim was to investigate the infectious conditions of Epstein-Barr virus(EBV)in patients with multiple sclerosis(MS).Methods:Cerebrospinal fluid(CSF)of 20 patients with MS and 20 with other neurological diseases(OND)were tested with indirect immunofluorescence for anti-EBV capsid antigen(EBV-CA)immunoglobulin G(IgG),IgG affinity for anti-EBV-CA,anti-EBV-CA immunoglobulin M(IgM),anti-EBV early antigen(EBV-EA)IgG and anti-EBV nuclear antigen(EBNA)IgG.According to the pattern of antibodies in CSF,infection rates of acute,chronic,primary,recurrent,and past infections were analyzed in the two groups of patients.Results:There were no significant differences in anti-EBV-CA,anti-EBC-EA,and anti-EBNA antigen IgG in CSF between MS and OND patients(P>0.05).The positive rate of low affinity for anti-EBV-CA IgG in MS patients was significantly higher than that for OND patients(75%vs.40%,P<0.05).Furthermore,significant differences in the positive rate of anti-EBV-CA IgM were found between MS and OND patients(70%vs.25%,P<0.05).Of the MS patients,75%were in an EBV acute infection state compared with 40%of OND patients(P<0.05).Conclusion:Acute infection of EBV closely correlates with the occurrence of MS.