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1.
Phys Rev Lett ; 132(17): 171001, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38728703

ABSTRACT

Recently a dark matter-electron (DM-electron) paradigm has drawn much attention. Models beyond the standard halo model describing DM accelerated by high energy celestial bodies are under intense examination as well. In this Letter, a velocity components analysis (VCA) method dedicated to swift analysis of accelerated DM-electron interactions via semiconductor detectors is proposed and the first HPGe detector-based accelerated DM-electron analysis is realized. Utilizing the method, the first germanium based constraint on sub-GeV solar reflected DM-electron interaction is presented with the 205.4 kg·day dataset from the CDEX-10 experiment. In the heavy mediator scenario, our result excels in the mass range of 5-15 keV/c^{2}, achieving a 3 orders of magnitude improvement comparing with previous semiconductor experiments. In the light mediator scenario, the strongest laboratory constraint for DM lighter than 0.1 MeV/c^{2} is presented. The result proves the feasibility and demonstrates the vast potential of the VCA technique in future accelerated DM-electron analyses with semiconductor detectors.

2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(11): 1862-1868, 2023 Nov 06.
Article in Chinese | MEDLINE | ID: mdl-38008578

ABSTRACT

This study used machine learning techniques combined with routine blood cell analysis parameters to build preliminary prediction models, helping differentiate patients with depression from healthy controls, or patients with anxiety. A multicenter study was performed by collecting blood cell analysis data of Beijing Chaoyang Hospital and the First Hospital of Hebei Medical University from 2020 to 2021. Machine learning techniques, including support vector machine, decision tree, naïve Bayes, random forest and multi-layer perceptron were explored to establish a prediction model of depression. The results showed that based on the blood cell analysis results of healthy controls and depression group, the accuracy of prediction model reached as high as 0.99, F1 was 0.975. Receiver operating characteristic curve area and average accuracy were 0.985 and 0.967, respectively. Platelet parameters contributed mostly to depression prediction model. While, to random forest differential diagnosis model based on the data from depression and anxiety groups, prediction accuracy reached 0.68 and AUC 0.622. Age, platelet parameters, and average volume of red blood cells contributed the most to the model. In conclusion, the study researched on the prediction model of depression by exploring blood cell analysis parameters, revealing that machine learning models were more objective in the evaluation of mental illness.


Subject(s)
Depression , Machine Learning , Humans , Bayes Theorem , Support Vector Machine , Blood Cell Count
3.
Article in Chinese | MEDLINE | ID: mdl-37524680

ABSTRACT

Objective: To analyze the pathological classification of malignant peritoneal mesothelioma (MPeM) and screen the immunohistochemical markers that can distinguish MPeM from peritoneal metastatic carcinoma (PC) . Methods: In June 2020, the pathological results of peritoneal biopsy of 158 MPeM and 138 PC patients from Cangzhou Central Hospital, Cangzhou People's Hospital, and Cangzhou Hospital of Integrated Traditional Chinese and Western Medicine from May 2011 to July 2019 were retrospectively analyzed, and the pathological classifications of MPeM in Cangzhou were summarized. Immunohistochemical markers of MPeM and PC patients were analyzed, and receiver operating characteristic curve (ROC curve) was drawn for differential diagnosis of MPeM and PC. Results: There were 55 male and 103 female MPeM patients in Cangzhou, with an average age of 57.1 years old. The asbestos exposure rate was 91.14% (144/158). The most common pathological classifications were cutaneous type, accounting for 90.51% (143/158). There were significant differences in the expression of calreticulum protein, CK5/6, vimentin, D2-40, carcinoembryonic antigen (CEA) and tail type homologous nuclear gene transcription factor 2 (CDX-2) between MPeM and PC (P<0.05). Among the 6 positive markers, the sensitivity of calreticulum protein was the highest (0.905) and CEA was the lowest (0.428) . Conclusion: Calreticulum protein, CK5/6, vimentin, D2-40, CEA and CDX-2 may be used as specific markers to distinguish the diagnosis of MPeM from PC.

4.
Phys Rev Lett ; 129(22): 221301, 2022 Nov 23.
Article in English | MEDLINE | ID: mdl-36493436

ABSTRACT

We present improved germanium-based constraints on sub-GeV dark matter via dark matter-electron (χ-e) scattering using the 205.4 kg·day dataset from the CDEX-10 experiment. Using a novel calculation technique, we attain predicted χ-e scattering spectra observable in high-purity germanium detectors. In the heavy mediator scenario, our results achieve 3 orders of magnitude of improvement for m_{χ} larger than 80 MeV/c^{2} compared to previous germanium-based χ-e results. We also present the most stringent χ-e cross-section limit to date among experiments using solid-state detectors for m_{χ} larger than 90 MeV/c^{2} with heavy mediators and m_{χ} larger than 100 MeV/c^{2} with electric dipole coupling. The result proves the feasibility and demonstrates the vast potential of a new χ-e detection method with high-purity germanium detectors in ultralow radioactive background.


Subject(s)
Electricity , Electrons
5.
Phys Rev Lett ; 129(22): 221802, 2022 Nov 23.
Article in English | MEDLINE | ID: mdl-36493447

ABSTRACT

A search for exotic dark matter (DM) in the sub-GeV mass range has been conducted using 205 kg day data taken from a p-type point contact germanium detector of the CDEX-10 experiment at China's Jinping underground laboratory. New low-mass dark matter searching channels, neutral current fermionic DM absorption (χ+A→ν+A) and DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), have been analyzed with an energy threshold of 160 eVee. No significant signal was found; thus new limits on the DM-nucleon interaction cross section are set for both models at the sub-GeV DM mass region. A cross section limit for the fermionic DM absorption is set to be 2.5×10^{-46} cm^{2} (90% C.L.) at DM mass of 10 MeV/c^{2}. For the DM-nucleus 3→2 scattering scenario, limits are extended to DM mass of 5 and 14 MeV/c^{2} for the massless dark photon and bound DM final state, respectively.


Subject(s)
Cell Nucleus , Photons
6.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(3): 406-408, 2021 Mar 06.
Article in Chinese | MEDLINE | ID: mdl-33730835

ABSTRACT

Among the staff of Beijing Chao-Yang Hospital, Capital Medical University, who received the inactivated SARS-CoV-2 vaccine on January 30 in 2021, 28 recipients were selected for this research. Samples for nucleic acid tests were collected from the surface of the recipients' both hands before and after vaccination. The hemostatic stickers used after the inoculation were also collected for nucleic acid tests. The nucleic acid tests of the samples collected from the surface of both hands of the 28 recipients before vaccination were all negative. After vaccination, the nucleic acid tests of the samples collected from the surface of both hands of recipients were positive in 3 cases, and suspicious in 8 cases, with a positive rate of 10.7%. A total of 25 hemostatic stickers used were collected, 24 of them had positive nucleic acid tests, and the rest one had suspicious nucleic acid test result, with a positive rate of 96%. The hemostatic stickers used after the inoculation have the risk of nucleic acid contamination.


Subject(s)
COVID-19 , Hemostatics , Nucleic Acids , COVID-19 Vaccines , Humans , SARS-CoV-2 , Vaccination
7.
Article in Chinese | MEDLINE | ID: mdl-32536066

ABSTRACT

Objective: To explore the relationship between the new Tumor-Node-Metastasis (TNM) staging system and the serum CA125 level with the prognosis of malignant peritoneal mesothelioma (MPeM) . Methods: The clinical data of 74 patients with MPeM diagnosed by pathology and immunohistochemistry were collected from January 2005 to June 2016 in Cangzhou Central Hospital. According to the results of CT-peritoneal carcinoma index (PCI) , the tumor load was divided into T1 (PCI 1-10) , T2 (PCI 11-20) , T3 (PCI 21-30) and T4 (PCI 31-39) , combined with lymph node metastasis and extraperitoneal metastasis, a new TNM staging system was established. And serum CA125 level was measured in the same time. The median survival time of patients with MPeM, the effect of the new TNM staging system, and serum CA125 levels on their prognosis were retrospectively analyzed. Results: Among the 74 patients with MPeM, 25 (33.8%) cases were males and 49 (66.2%) cases were females. There were 8 cases with systemic chemotherapy, 8 cases with heated intraperitoneal chemotherapy, and 1 case with combination chemotherapy. 10 cases were T1, 22 cases were T2, 27 cases were T3, 15 cases were T4, 12 cases had lymph node metastasis and 10 cases had distant metastasis. The median survival time of T1, T2, T3 and T4 were 12, 10, 6 and 3 months respectively. There were 38 (77.6%) cases with high serum CA125 in all 49 cases who have been tested for CA125. The median survival time of positive group and negative group were 6 months and 11 months respectively. 68 (91.9%) patients had died by the end of collecting data. The median survival time was 8 months. Univariate analysis showed that there were significant differences in survival time between patients with different CT-PCI stages, serum CA125 levels, and with or without lymph node and extraperitoneal metastasis (P<0.05) . Multivariate analysis showed that CT-PCI was independent risk factors for the prognosis of MPeM (HR=2.203, 95%CI: 1.475-3.289) . Conclusion: The new TNM staging system and serum CA125 are important for the prognosis of patients with MPeM. Early detection, early diagnosis and comprehensive treatment can improve the survival time of patients with MPeM.


Subject(s)
Mesothelioma , Peritoneal Neoplasms , CA-125 Antigen/analysis , Female , Humans , Male , Membrane Proteins/analysis , Mesothelioma/diagnosis , Neoplasm Staging , Peritoneal Neoplasms/diagnosis , Prognosis , Retrospective Studies , Survival Rate
8.
Zhonghua Yi Xue Za Zhi ; 100(10): 771-774, 2020 Mar 17.
Article in Chinese | MEDLINE | ID: mdl-32192291

ABSTRACT

Objective: To explore the association between serum brain-derived neurotrophic factor and clinical stage and dysmenorrhoea of endometriosis. Methods: A total of 82 patients were studied with laparoscopically diagnosed endometriosis between June 2017 and June 2019, and 75 healthy women with reproductive age were selected as the control group during the same period. The endometriosis patients were scored by visual analogue scale(VAS)according to their preoperative dysmenorrhoea.And endometriosis was staged and scored according to the score of Revised American Fertility Society(r-AFS).Enzyme-linked immunosorbent assay (ELISA) was used to determine preoperative BDNF level in serum, and the correlation between BDNF level with clinical stage as well as dysmenorrhea of endometriosis were analysed. Results: The serum BDNF level in endometriosis patients was (1 082±43) ng/L, significantly higher than that in the normal control [(649±30) ng/L], there was statistical difference between the two groups(P<0.001). The BDNF expression in patients with r-AFS stage Ⅲ-Ⅳ was higher than that in patients with Ⅰ-Ⅱ stage [(1 164±389) ng/L vs (791±218)ng/L, P<0.001]. BDNF level in serum was closely correlated with the degree of dysmenorrhea (r=0.682), and the BDNF level in patients with moderate or severe dysmenorrhea was significantly higher than that in patients without dysmenorrhea and patients with mild dysmenorrhea [(1 292±43) ng/L vs(718±36) ng/L, P<0.001]. Conclusions: The serum BDNF level in endometriosis patients is positively correlated with clinical stage and dysmenorrhea.


Subject(s)
Dysmenorrhea , Endometriosis , Brain-Derived Neurotrophic Factor , Female , Humans
9.
Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 32(15): 1130-1133, 2018 Aug 05.
Article in Chinese | MEDLINE | ID: mdl-30282142

ABSTRACT

Objective:To explore the equivalence of the test results of the water or air caloric tests and the compliance of the test in the healthy individuals. To provide scientific basis for clinical standardization of caloric test.Method: Randomized crossover clinical trial, 60 healthy individuals were divided into group A and group B. Water caloric test was carried out first in group A, and air caloric test was carried out after elution effect(one day interval). The treatment of group B was opposite to group A. SPV(Slow Phase Velocity), CP(canal paralysis) and SPV and CP' s 95%CI were used as evaluation indexes to analyze the equivalence of water and air caloric test in healthy people and the clinical normal reference value and stability and compliance of the water and air caloric test. Result: ①60 cases of caloric test CP value of chi square test suggested that there was no statistical difference between two kinds of media in the examination of the vestibular function of healthy individuals, and the CP value of the two was 85%(51/60). ②the SPV value of the was obviously higher than that of the air caloric test. The SPV value at each temperature of the water caloric test stimulation is quite different from the air caloric test stimulation. ③The range of water caloric test stimulation CP 95%CI was 8%-12%, and the average value was 10%. The interval of air caloric test stimulation CP 95%CI was 10%-15% and the average value was 12%. ④This study provided the corresponding SPV 95%CI as the medical reference values. ⑤The subjects of 98.33%(59/60) of the questionnaire survey selecting air caloric test and the results of the observation indicated that the duration of the air caloric test was shorter and more comfortable. Conclusion: ①Air caloric test can satisfied the needs of clinical assessment of horizontal semicircular canal function, and can make patients feel more comfortable. However, due to the weak intensity of nystagmus, water caloric test has to be used when the SPV value is too low. ②In this study, the upper limit of the CP value of the air caloric test in healthy individuals was 0.21, which is quite different from the upper limit of the standard value was 0.25 of the water caloric test. Therefore, the laboratory should establish their own reference value of the laboratory caloric test, and should not blindly apply the standard value of the water caloric test as the standard of the hemiplegia of the unilateral semicircular canal. The results of this study suggest that air caloric test can be used instead of water caloric test in clinic. And if the patient has no contraindications, air caloric test can be used as a priority.

11.
Eur Rev Med Pharmacol Sci ; 21(1): 30-36, 2017 01.
Article in English | MEDLINE | ID: mdl-28121360

ABSTRACT

OBJECTIVE: The present study is aimed to explore the correlation between PAI-1 gene mediated by NF-κB signaling pathway and human sepsis. PATIENTS AND METHODS: In this study, we used 74 cases of sepsis patients preserved by the laboratory as the observation group, and 68 cases of healthy people served the control group. Further methods like fluorescence quantitative PCR, enzyme-linked immunosorbent assay, Western-blotting were used to determine NF-B expression, NF-κB gene mRNA analyses and protein expression on different research subjects. Further, the positive expression rates of PAI-1 gene in the observation group and the control group were determined by immunohistochemistry. RESULTS: The expression levels of NF-κB and PAI-1 gene mRNA in the blood of the observation group significantly increased in comparison to control group (X2 = 3.24, p < 0.05; X2 = 2.81, p < 0.05). Also, NF-κF and PAI-1 gene protein expressions (0.14 ug/l, 0.32 ug/l) were significantly higher in the observation group in comparison to control group (p < 0.05). The results of blood glucose measurement showed that the fasting blood glucose (14.3 mmol/l) in the observation group was significantly higher than that in the control group (4.6 mmol/l). Immunohistochemical were also in sync with above results. CONCLUSIONS: The present study concludes that PAI-1 gene expression gets significantly increased via NF-κF signaling pathway during sepsis.


Subject(s)
NF-kappa B/metabolism , Plasminogen Activator Inhibitor 1/genetics , Sepsis/genetics , Signal Transduction , Adolescent , Adult , Blood Glucose/analysis , Case-Control Studies , Gene Expression , Humans , Middle Aged , Young Adult
13.
Phys Rev Lett ; 114(5): 055001, 2015 Feb 06.
Article in English | MEDLINE | ID: mdl-25699449

ABSTRACT

A critical challenge facing the basic long-pulse high-confinement operation scenario (H mode) for ITER is to control a magnetohydrodynamic (MHD) instability, known as the edge localized mode (ELM), which leads to cyclical high peak heat and particle fluxes at the plasma facing components. A breakthrough is made in the Experimental Advanced Superconducting Tokamak in achieving a new steady-state H mode without the presence of ELMs for a duration exceeding hundreds of energy confinement times, by using a novel technique of continuous real-time injection of a lithium (Li) aerosol into the edge plasma. The steady-state ELM-free H mode is accompanied by a strong edge coherent MHD mode (ECM) at a frequency of 35-40 kHz with a poloidal wavelength of 10.2 cm in the ion diamagnetic drift direction, providing continuous heat and particle exhaust, thus preventing the transient heat deposition on plasma facing components and impurity accumulation in the confined plasma. It is truly remarkable that Li injection appears to promote the growth of the ECM, owing to the increase in Li concentration and hence collisionality at the edge, as predicted by GYRO simulations. This new steady-state ELM-free H-mode regime, enabled by real-time Li injection, may open a new avenue for next-step fusion development.

14.
Phys Rev Lett ; 112(18): 185004, 2014 May 09.
Article in English | MEDLINE | ID: mdl-24856704

ABSTRACT

An electrostatic coherent mode near the electron diamagnetic frequency (20-90 kHz) is observed in the steep-gradient pedestal region of long pulse H-mode plasmas in the Experimental Advanced Superconducting Tokamak, using a newly developed dual gas-puff-imaging system and diamond-coated reciprocating probes. The mode propagates in the electron diamagnetic direction in the plasma frame with poloidal wavelength of ∼8 cm. The mode drives a significant outflow of particles and heat as measured directly with the probes, thus greatly facilitating long pulse H-mode sustainment. This mode shows the nature of dissipative trapped electron mode, as evidenced by gyrokinetic turbulence simulations.

15.
Phys Rev Lett ; 100(10): 102003, 2008 Mar 14.
Article in English | MEDLINE | ID: mdl-18352176

ABSTRACT

The decays of J/psi --> etaphif(0)(980)[eta --> gammagamma, phi --> K(+) K(-), f(0)(980) --> pi(+)pi(-)] are analyzed using a sample of 5.8 x 10(7) J/psi events collected with the BESII detector at the Beijing Electron-Positron Collider. A structure at around 2.18 GeV/c(2) with about 5 sigma significance is observed in the phif(0)(980) invariant mass spectrum. A fit with a Breit-Wigner function gives the peak mass and width of m = 2.186+/-0.010(stat)+/-0.006(syst) GeV/c(2) and Gamma = 0.065+/-0.023(stat)+/-0.017(syst) GeV/c(2), respectively, which are consistent with those of Y(2175), observed by the BABAR Collaboration in the initial-state radiation process e(+)e(-) --> gamma(ISR) phif(0)(980). The production branching ratio is determined to be Br(J/psi --> etaY(2175))Br(Y(2175)- -> phif(0)(980))Br(f(0)(980) --> pi(+)pi(-)) = [3.23+/-0.75(stat)+/-0.73(syst)] x 10(-4), assuming that the Y(2175) is a 1(--) state.

16.
J Pharm Pharmacol ; 56(5): 649-54, 2004 May.
Article in English | MEDLINE | ID: mdl-15142343

ABSTRACT

There is continued interest in the assessment and potential use of antioxidants as neuroprotective agents in diseases associated with increased oxidative stress, such as Parkinson's disease. The neuroprotective effect of a natural antioxidant drink, EM-X (a ferment derivative of unpolished rice, papaya and seaweeds with effective microorganisms), was investigated using the 6-hydroxydopamine (6-OHDA)-lesion rat model of Parkinson's disease. The nigrostriatal dopaminergic neurons were unilaterally lesioned with 6-OHDA (8 microg) in rats that were treated with a 10-times diluted EM-X drink (dilEM-X), standard EM-X drink (stdEM-X) or tap water for 4 days. Seven days post lesion, the integrity (no. of tyrosine hydroxylase positive cells (TH+ cells) in the substantia nigra pars compacta (SNpc)) and functionality (dopamine and its metabolites DOPAC and HVA content in the striata) of nigrostriatal dopaminergic neurons were assessed. In the vehicle-treated rats, infusion of 8 microg of 6-OHDA significantly reduced the number of TH+ cells in the SNpc as well as the levels of dopamine, DOPAC and HVA in the striata on the lesion side. The loss of TH+ cells, dopamine and HVA, but not the DOPAC levels, was significantly attenuated by stdEM-X pretreatment, but not by the dilEM-X pretreatment. There were no significant changes in the TH+ cells, or in the monoamine levels with the EM-X pretreatment per se, except for a small but significant fall in the levels of dopamine with the stdEM-X. The evidence presented supports the potential neuroprotective effects of stdEM-X drink, although its effect on dopamine levels needs further investigation.


Subject(s)
Antioxidants/pharmacology , Corpus Striatum/drug effects , Dopamine/metabolism , Glycosides/pharmacology , Kaempferols/pharmacology , Neurons/drug effects , Neuroprotective Agents/pharmacology , Parkinson Disease/drug therapy , Substantia Nigra/drug effects , 3,4-Dihydroxyphenylacetic Acid/metabolism , Animals , Antioxidants/administration & dosage , Beverages , Corpus Striatum/metabolism , Corpus Striatum/pathology , Dose-Response Relationship, Drug , Male , Neurons/metabolism , Neuroprotective Agents/administration & dosage , Oxidopamine , Parkinson Disease/metabolism , Parkinson Disease/pathology , Rats , Rats, Sprague-Dawley , Substantia Nigra/metabolism , Substantia Nigra/pathology , Time Factors , Tyrosine 3-Monooxygenase/metabolism
17.
Environ Res ; 87(1): 47-54, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11534964

ABSTRACT

Epidemiological studies have shown an association between exposure to indoor air pollution from Chinese-style cooking and risk of lung cancer among Chinese females. Several toxic substances have been identified in cooking oil fumes (COF) collected from heated rapeseed oil. In this study, we examined the biological effects of COF on CL3 human lung epithelial cells. Exposure to 200 microg/ml COF significantly reduced cell growth within 4 days. In addition, we examined the effect of COF on TGFbeta1, TGFbeta2, IL-6, IL-8, and IFN-gamma gene expressions with the RT-PCR method. We found that TGFbeta1 mRNA levels increased after exposure to 200 microg/ml COF for 24 h. Similarly, exposure to 10 microM benzo[a]pyrene or 100 nM 12-O-tetradecanoylphorbol-13-acetate increased TGFbeta1 mRNA levels at 24 h. The mRNA levels of TGFbeta2, IL-6, IL-8, and IFN-gamma did not increase after treatment with COF, benzo[a]pyrene, or 12-O-tetradecanoylphorbol-13-acetate. COF-induced TGFbeta1 production was confirmed by quantification of TGFbeta1 in conditioned medium with enzyme-linked immunosorbent assay. Exposure to 200 microg/ml COF significantly increased TGFbeta1 secretion in a time-dependent and dose-dependent manner. It has been demonstrated that reactive oxygen intermediates induce TGFbeta1 gene expression. When CL3 cells were exposed to 200 microg/ml COF for 15 min, there was an increase in intracellular peroxide formation with the dichlorofluorescein method. Furthermore, treatment with 200 microg/ml COF for 12 h also significantly induced lipid peroxidation in CL3 cells. Our results show that exposure to COF inhibits cell growth, increases TGFbeta1 secretion, and induces oxidative stress in CL3 lung epithelial cells. This suggests that TGFbeta1 and oxidative stress play a role in the biological effects of COF on lung epithelial cells.


Subject(s)
Air Pollution, Indoor/adverse effects , Cooking , Cytokines/biosynthesis , Epithelial Cells/physiology , Lung/cytology , Oxidative Stress , Plant Oils , Cell Culture Techniques , Cell Division , China , DNA Primers , Gene Expression Regulation , Humans , Lung/pathology , Reverse Transcriptase Polymerase Chain Reaction
18.
J Physiol ; 532(Pt 1): 229-39, 2001 Apr 01.
Article in English | MEDLINE | ID: mdl-11283237

ABSTRACT

Excitation and sensitization to heat of nociceptors by bradykinin (BK) were examined using an isolated rat skin-saphenous nerve preparation. A total of 52 C-fibres was tested: 42 were mechano-heat sensitive (CMH) and 40% of them were excited and sensitized to heat by BK superfusion (10-5 M, 5 min) of their receptive fields; heat responses were augmented by more than five times and heat thresholds dropped to 36.4 degrees C, on average. Sixty per cent of the CMH did not respond to BK itself, but 3/4 of these units showed an increase in their heat responses by more than 100% following BK exposure. Ten high-threshold mechanosensitive C-fibres did not discharge upon BK application but following this five of them responded to heat in a well-graded manner. In all fibres, the sensitizing effect of BK was abolished within 9 min or less of wash-out, and it could be reproduced several times at equal magnitude, whereas the excitatory effect of BK regularly showed profound tachyphylaxis. Sustained superfusion (20 min) of BK induced a desensitizing excitatory response while superimposed heat responses showed constant degrees of sensitization. The large extent and high prevalence of BK-induced sensitization (almost 80% of all fibres tested) and de novo recruitment of heat sensitivity suggest a prominent role of BK not only in hyperalgesia but also in sustained inflammatory pain which may be driven by body or even lower local temperatures acting on sensitized nociceptors. Based on the latter assumption, a hypothesis is put forward that excludes a direct excitatory effect of BK on nociceptors, but assumes a temperature-controlled activation as a result of rapid and profound sensitization.


Subject(s)
Bradykinin/pharmacology , Hot Temperature , Nerve Fibers/physiology , Nociceptors/physiology , Skin/innervation , Tachyphylaxis/physiology , Action Potentials/physiology , Animals , In Vitro Techniques , Male , Mechanoreceptors/drug effects , Mechanoreceptors/physiology , Nerve Fibers/drug effects , Nociceptors/drug effects , Rats , Rats, Wistar , Skin/metabolism
19.
J Nutr ; 130(12): 3085-9, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11110874

ABSTRACT

We investigated the effects of a mixture of dietary nucleosides and nucleotides (NS + NT) on memory in 1- and 7-mo-old senescence-accelerated mice (SAM). Memory retention was studied with passive avoidance (step-through) and active avoidance (shuttle) tests. For 14 wk, mice in the control groups were fed a 20 g of casein/100 g diet, whereas the NS + NT groups were fed this diet supplemented with a 0.5 g of NS + NT mixture/100 g. All mice were killed at wk 14, and we studied the brain histopathology. Lipofuscin, monovacuoles and multiple vacuoles of various brain regions were measured. Body weight, food intake and ambulatory activity did not differ between the control and NS + NT groups. In old mice, the time of passive avoidance was significantly higher in the NS + NT group than in the control group at d 1 and 7 (P: < 0.05). However, such an effect of NS + NT was not observed in young mice. In the active avoidance test, the incidence of successful avoidance in old mice was higher in the NS + NT group than in the control group at d 1 and 2 (P: < 0.05). The percentages of specific brain cells containing lipofuscin were lower in NS + NT groups than in the control groups in both young and old mice (P: < 0.05). The number of monovacuoles and multiple vacuoles in specific brain regions tended to be lower (P: = 0.1-0.25) in NS + NT than in control groups, with significant differences in the microvacuoles of the middle cortex of young mice and in the multiple vacuoles in the hind cortex of old mice (P: < 0. 05). These results suggest that increased dietary NS + NT may be associated with decreases in the age-induced deterioration of brain morphology and certain memory tasks.


Subject(s)
Aging/drug effects , Brain/pathology , Memory Disorders/diet therapy , Memory/drug effects , Nucleosides/pharmacology , Nucleotides/pharmacology , Age Factors , Animals , Avoidance Learning/drug effects , Body Weight , Eating , Lipofuscin/analysis , Male , Mice , Motor Activity , Nucleosides/administration & dosage , Nucleotides/administration & dosage , Time Factors , Vacuoles
20.
J Comp Neurol ; 360(4): 621-33, 1995 Oct 02.
Article in English | MEDLINE | ID: mdl-8801254

ABSTRACT

Intrasomal recording and horseradish peroxidase injection techniques were employed in vivo to determine the morphological characteristics of touch, temperature, and mechanical nociceptive neurons in the trigeminal ganglia of crotaline snakes. The touch neurons, with a peripheral axon conducting at the A-beta range, could be subdivided into tactile and vibrotactile neurons according to their response properties, but there were no morphological differences between them. These neurons exhibited a large and oval soma and possessed a set of large stem, peripheral, and central axons which were all myelinated and equal in diameter with a constriction at the bifurcation. The temperature neurons, which conducted peripherally at the A-delta range, were physiologically separated into thermosensitive and thermo-mechanosensitive neurons, which were also morphologically indistinguishable. The temperature neurons had a round soma of medium size and a set of medium axons with varied axonal bifurcation patterns. All axons of these neurons were myelinated, but the central axon was thinner than the stem and peripheral axons. The mechanical nociceptive neurons, which had a peripheral axon conducting at the A-delta range, were morphologically heterogeneous based on their conduction velocities. The neurons conducting at the fast A-delta range were morphologically similar to the temperature neurons in the ganglion excepting their thinner central axons, whereas those at the slow A-delta range had a thinner myelinated stem axon that gave rise to a thinner myelinated peripheral axon and an unmyelinated stem axon with a bifurcation of either a triangular expansion at the bifurcating point or a central axon arising straightforwardly from the constant stem and peripheral axons. This study revealed that distinct morphological characteristics do exist for the touch and temperature neurons and the subtypes of mechanical nociceptive neurons in the trigeminal ganglion, but not for the subfunctional types of touch neurons or temperature neurons.


Subject(s)
Neurons/classification , Neurons/physiology , Nociceptors/physiology , Temperature , Touch/physiology , Trigeminal Ganglion/physiology , Animals , Axons/physiology , Cell Count , Female , Horseradish Peroxidase , Male , Snakes
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