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1.
ACS Omega ; 6(31): 20629-20636, 2021 Aug 10.
Article in English | MEDLINE | ID: mdl-34396008

ABSTRACT

In this study, the B 1Π excited state of NaH has been experimentally studied for the first time. Pulsed laser-induced fluorescence excitation spectroscopy was used to investigate the B 1Π electronic state of NaH. A total of 48 ro-vibronic transitions were observed, including within the B-X (0-0) and B-X (0-1) transition bands. Only one B-state vibrational level was identified, and a series of PQR lines, with eight e-parity and eight f-parity sublevels (v' = 0, J' = 1-8), were assigned. The level assignment was supported by a comparison of the experimental line positions with the ab initio calculations, the dispersed laser-induced fluorescence spectrum of the NaH B 1Π â†’ X 1∑+ emission, and the V-type optical-optical double resonance spectra. The Dunham-type coefficients, the mean internuclear distance, the harmonic vibrational frequency ω, and the dissociation energies D 0 and D e of the B 1Π state were determined.

2.
Opt Express ; 28(18): 26313-26323, 2020 Aug 31.
Article in English | MEDLINE | ID: mdl-32906905

ABSTRACT

The effect of polarization on the ladder-type electromagnetically induced transparency (EIT) spectra of 133Cs atoms at room temperature for the transitions 62P1/2-62P3/2-112S1/2 is experimentally studied. The entire spectra with additional peaks arising from the Doppler effect are observed. As the relative angle between the probe's and coupling's plane of polarization arranges at 0°, 45°, and 90°, the peak height ratio of 44'3" to 44'4" increases by more than 7 times with corresponding values of 0.19, 0.69, and 1.4. Meanwhile, that of 45'4" to 44'4" are found to be 0.61, 0.87, and 1.23 (doubled), respectively. A theoretical model built to explain the experimental results with the considerations of optical pumping effect, two-photon transition probability, dephasing rate, and integration all over the velocity distribution. The simulation and experimental results are well-agreed.

3.
J Chem Phys ; 150(2): 024303, 2019 Jan 14.
Article in English | MEDLINE | ID: mdl-30646708

ABSTRACT

The 2 1Π state of NaH has been observed up to the last bound vibrational level using pulsed optical-optical double resonance fluorescence depletion spectroscopy. A total of 20 rovibrational energy levels ( v = 2-4 and J = 1-9) were assigned to this electronic state by means of comparing the successive rovibrational spectra to the eigenvalues of the ab initio potential energy curve. The decrease of background fluorescence near the atomic asymptotic limit Na(3d) + H(1s) is an indication of reaching the dissociation limit of the NaH 2 1Π state. Unobserved rovibrational levels ( v = 0 and 1) are due to poor Franck-Condon overlap of 2 1Π â† A 1Σ+ transition within the accessible rovibrational levels of intermediate A 1Σ+ state of this work.

4.
J Chem Phys ; 148(11): 114301, 2018 Mar 21.
Article in English | MEDLINE | ID: mdl-29566521

ABSTRACT

Vibrational levels (v = 6-42) of the NaH C 1Σ+ state including the inner and outer wells and the near-dissociation region were observed by pulsed optical-optical double resonance fluorescence depletion spectroscopy. The absolute vibrational quantum number is identified by comparing the vibrational energy difference of this experiment with the ab initio calculations. The outer well with v up to 34 is analyzed using the Dunham expansion and a Rydberg-Klein-Rees (RKR) potential energy curve is constructed. A hybrid double-well potential combined with the RKR potential, the ab initio calculation, and a long-range potential is able to describe the whole NaH C 1Σ+ state including the higher vibrational levels (v = 35-42). The dissociation energy of the NaH C 1Σ+ state is determined to be De(C) = 6595.10 ± 5 cm-1 and then the dissociation energy of the NaH ground state De(X) = 15 807.87 ± 5 cm-1 can be derived.

5.
J Chem Phys ; 147(2): 024301, 2017 Jul 14.
Article in English | MEDLINE | ID: mdl-28711041

ABSTRACT

Stimulated emission pumping with fluorescence depletion spectroscopy is used to determine the NaD X 1Σ+ ground-state dissociation energy and its isotopic shift. A total of 230 rovibrational levels in the range 9 ≤ v″ ≤ 29 and 1 ≤ J″ ≤ 11 are observed, where v″ = 29 is about 50 cm-1 below the dissociation limit. Analysis of the highest five vibrational levels yields the dissociation energy De = 15 822 ± 5 cm-1 with a vibrational quantum number at dissociation vD = 31.2 ± 0.1. The energy difference in the well depth of this isotopologue with respect to that of NaH is δDe = De(NaH) - De(NaD) = -7 cm-1. A new set of Dunham coefficients is derived to fit all the observed energy levels to within the experimental uncertainty.

6.
BMC Complement Altern Med ; 14: 30, 2014 Jan 18.
Article in English | MEDLINE | ID: mdl-24438349

ABSTRACT

BACKGROUND: The active components of Gardenia (Gardenia jasminoides Ellis, GJ) exhibit a hypoglycemic effect by improving insulin secretion and lowering plasma lipids. In the present study, we fed a water extract of gardenia to steroid-induced insulin-resistant (SIIR) rats and observed changes in signaling proteins in order to elucidate the mechanisms of the insulin-sensitizing effect of GJ and evaluate its possibility as an insulin-sensitizing agent. METHODS: Normal Wistar rats were randomly divided into a control group (i.e., saline) and experimental groups (GJ 100 and 200 mg/kg). Blood samples were taken at 0, 30, and 60 min for plasma glucose assay in order to determine the optimal dose to induce the hypoglycemic effect. SIIR rats were then randomly divided into a control group (i.e., saline) and an experimental group (optimal dose of gardenia extract) to observe the insulin-sensitizing effect of the extract. Finally, western blot analysis was performed to detect intracellular signaling proteins to elucidate the mechanisms of the insulin-sensitization effect of GJ. RESULTS: The normal Wistar rats in the GJ 200 mg/kg group exhibited significant hypoglycemic activity. Meanwhile, the SIIR rats had higher plasma glucose levels than normal rats. There was no obvious change in insulin level, but the insulin sensitivity index and homeostasis model assessment index were significantly elevated. Meanwhile, a significant hypoglycemic effect was observed with GJ 200 mg/kg. In addition, intracellular signaling proteins including insulin receptor substrate-1 (IRS-1) and peroxisome proliferator-activated receptor (PPARγ) were elevated in muscle cells. CONCLUSIONS: The optimal dose of GJ aqueous extract of 200 mg/kg exerts a PPARγ-activating hypoglycemic effect and improves insulin resistance in SIIR rats. Therefore, it is a potential insulin-sensitizing agent in type 2 diabetes mellitus with insulin resistance.


Subject(s)
Diabetes Mellitus, Type 2/blood , Gardenia , Hypoglycemic Agents/pharmacology , Insulin Resistance , Insulin/blood , Peroxisome Proliferator-Activated Receptors/metabolism , Plant Extracts/pharmacology , Animals , Blood Glucose/metabolism , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/metabolism , Hypoglycemic Agents/therapeutic use , Insulin Receptor Substrate Proteins/metabolism , Male , Muscles/drug effects , Muscles/metabolism , PPAR gamma/metabolism , Phytotherapy , Plant Extracts/therapeutic use , Rats, Wistar , Steroids
7.
Article in English | MEDLINE | ID: mdl-23983807

ABSTRACT

Aims. To evaluate the efficacy of rosiglitazone (TZD) and electroacupuncture (EA) combined therapy as a treatment for type 2 diabetes mellitus (T2DM) patients by randomized single-blind placebo controlled clinical trial. Methods. A total of 31 newly diagnostic T2DM patients, who fulfilled the study's eligibility criteria, were recruited. The individuals were randomly assigned into two groups, the control group (TZD, N = 15) and the experimental group (TZD + EA, N = 16). Changes in their plasma free fatty acid (FFA), glucose, and insulin levels, together with their homeostasis model assessment (HOMA) indices, were statistically compared before and after treatment. Hypoglycemic activity (%) was also compared between these two groups. Results. There was no significant difference in hypoglycemic activity between the TZD and TZD + EA group. The effectiveness of the combined therapy seems to derive from an improvement in insulin resistance and a significant lowering of the secreted insulin rather than the effect of TZD alone on T2DM. The combined treatment had no significant adverse effects. A lower plasma FFA concentration is likely to be the mechanism that causes this effect. Conclusion. This combined therapy seems to suppress endogenous insulin secretion by improving insulin resistance via a mechanism involving a reduction in plasma FFA. This trial is registered with ClinicalTrials.gov NCT01577095.

8.
Int J Med Mushrooms ; 15(3): 277-86, 2013.
Article in English | MEDLINE | ID: mdl-23662615

ABSTRACT

In our previous research, Cordyceps militaris (CM) had a hypoglycemic effect in normal rats. In this study we wanted to elucidate whether CM also had an effect on diabetic rats. Twelve rats with streptozotocin-induced diabetes were separated randomly into 2 groups. First, aqueous extracts of CM 10 mg/kg (CM group) or saline (control group) was fed to the rats; then the plasma glucose levels were assayed. Second, the signaling proteins IRS-1 and GLUT-4 collected from the muscle were detected. Finally, another 2 groups of rats were injected with atropine 0.1 mg/kg intraperitoneally just before the CM/saline feeding, and the assays mentioned above were repeated. Blood glucose decreased 7.2% in the CM group but only 1.5% in the control group (P < 0.05). The IRS-1 signal was 2.9-fold higher than actin in the CM group but only 0.8-fold higher in the control group (P < 0.005). In GLUT-4 signal, the difference was 1.7- vs. 0.6-fold, respectively, compared with actin (P < 0.05). However, atropine injection made CM-induced hypoglycemia or elevation of IRS-1 and GLUT-4 not significant. In conclusion, CM had a hypoglycemic effect in diabetic rats and atropine blocked it. Therefore, the cholinergic activation also was considered to be involved in the hypoglycemic effect of CM in rats with streptozotocin-induced diabetes.


Subject(s)
Blood Glucose/drug effects , Cholinergic Agents/pharmacology , Cholinergic Fibers/drug effects , Cordyceps/chemistry , Diabetes Mellitus, Experimental/drug therapy , Hypoglycemic Agents/pharmacology , Animals , Atropine/antagonists & inhibitors , Chemical Fractionation , Cholinergic Agents/chemistry , Hypoglycemic Agents/chemistry , Male , Random Allocation , Rats , Rats, Wistar , Water
9.
Phytother Res ; 26(8): 1173-7, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22821853

ABSTRACT

Previous studies have shown that Cordyceps militaris (CM) has a hypoglycemic effect, but the actual mechanism remains unclear. This study explored the hypoglycemic mechanism of aqueous extracts of CM in normal Wistar rats. First, the optimal dose of CM for lowering plasma glucose and insulin secretion was tested. Further, atropine and hemicholinium-3 (HC-3) were injected and a western blot was used to investigate insulin signaling. It was found that 10 mg/kg CM extracts had a stronger hypoglycemic effect than a higher dose (100 mg/kg); therefore, a dose of 10 mg/kg was used in subsequent experiments. In normal rats, CM extracts decreased plasma glucose by 21.0% and induced additional insulin secretion by 54.5% after 30 min. When atropine or HC-3 was injected, CM induced a hypoglycemic effect, but the enhancement of insulin secretion was blocked. By western blotting, significant increases in the insulin receptor substrate 1 (IRS-1) and glucose transporter 4 (GLUT-4) were observed after CM feeding. However, the elevation of these signaling proteins was abolished by atropine or HC-3. Taken together, these findings indicate that CM can lower plasma glucose via the stimulation of insulin secretion and cholinergic activation involved in the hypoglycemic mechanism of normal Wistar rats.


Subject(s)
Blood Glucose/drug effects , Cholinergic Agents/pharmacology , Cordyceps/chemistry , Hypoglycemic Agents/pharmacology , Insulin/metabolism , Animals , Atropine/administration & dosage , Atropine/pharmacology , Blood Glucose/metabolism , Blotting, Western , Cholinergic Fibers/drug effects , Cholinergic Fibers/metabolism , Disease Models, Animal , Glucose Transporter Type 4/metabolism , Hemicholinium 3/administration & dosage , Hemicholinium 3/pharmacology , Insulin Receptor Substrate Proteins/metabolism , Insulin Secretion , Male , Rats , Rats, Wistar
10.
Opt Express ; 20(13): 14419-27, 2012 Jun 18.
Article in English | MEDLINE | ID: mdl-22714503

ABSTRACT

The probability of two-photon transition (TPT) under a control field to inhibit the quantum interference and enhance the nonlinear optical cross section is observed. Essentially, this is a V-type electromagnetically induced transparency (EIT) with TPT instead of one photon transition. Numerical simulation based on solving the steady state density matrix can qualitatively fit the experimental data. A model of double-Lorentzian profile is used to fit the observed spectrum and give the de-convolution information of the inhibition of TPT spectrum due to EIT and enhancement on the wings of TPT. The frequency shift of the inhibit center is linear to the intensity of the control field (one-photon) and quadratic to the intensity of probe field (two-photon). Under the control field, a factor of 10 enhancements on the wings of the TPT is observed.


Subject(s)
Cesium/chemistry , Models, Chemical , Photons , Computer Simulation , Light , Scattering, Radiation
11.
J Chem Phys ; 133(4): 044301, 2010 Jul 28.
Article in English | MEDLINE | ID: mdl-20687644

ABSTRACT

The dissociation energy of the ground state of NaH was determined by analyzing the observed near dissociation rovibrational levels. These levels were reached by stimulated emission pumping and fluorescence depletion spectroscopy. A total of 114 rovibrational levels in the ranges 9

12.
J Phys Chem A ; 113(17): 4954-62, 2009 Apr 30.
Article in English | MEDLINE | ID: mdl-19385677

ABSTRACT

We present detailed investigations of our previously reported observations of the 3(1)Delta(g) and 4(1)Delta(g) Rydberg states having separated-atom limits of Na(3s) + Na(4d) and Na(3s) + Na(4f), respectively, of Na(2) using high-resolution cw optical-optical double resonance spectroscopic measurements and analyzing the assigned rovibrational energy levels both by the individual linear fit method and the Dunham polynomial fit method. We have sorted out e/f-parity observed energy levels, and then from the Dunham polynomial fits of the e-parity levels, we have derived molecular constants and constructed Rydberg-Klein-Rees potentials of the 3(1)Delta(g) and 4(1)Delta(g) states, which appear to be twin states with an avoided crossing at R(c) = 4.10 A and a splitting of DeltaE(c) = 94 cm(-1). The potentials are in good agreement with the ab initio calculations and linear fit results. The Lambda-doubling splittings and the (f-d) l-mixing are investigated. A detailed discussion is focused on the adiabatic interaction of the perturbed molecular wave functions/states causing mutual amplitude/intensity sharing giving rise to avoided crossing between the 3(1)Delta(g) and 4(1)Delta(g) states.

13.
J Chem Phys ; 129(2): 024303, 2008 Jul 14.
Article in English | MEDLINE | ID: mdl-18624529

ABSTRACT

The nd (1)Delta(g) (n = 6, 7, and 8) Rydberg states of Na(2) correlating with the asymptotic limits of Na(3s) + Na(nd) have been observed using high-resolution cw optical-optical double resonance spectroscopy corresponding to the rovibrational transitions X (1)Sigma(g)(+)(v("),J(")) + h nu(pump) --> B (1)Pi(u)(v('),J(')) + h nu(probe) --> nd (1)Delta(g)(v,J). Totals of 104, 83, and 45 identified rovibrational e/f-parity levels in the ranges of v = 0-11, 11 < or = J < or = 83; v = 0-10, 11 < or = J < or = 83; and v = 0-10, 11 < or = J < or = 65, have been assigned to the 6d (1)Delta(g), 7d (1)Delta(g), and 8d (1)Delta(g) states, respectively. Using the observed quantum levels, molecular constants were determined from the Dunham fits of the e-parity levels and the Rydberg-Klein-Rees potential curves were constructed for the nd (1)Delta(g)(n = 6-8) states. The characteristics of the estimated Lambda-doubling splitting constants (q(0), q(v), and mu) with n(= 5-8) of the nd (1)Delta(g) series have been explored. Detailed investigations reveal that the nd (1)Delta(g)(n = 6-8) states involve L uncoupling from the internuclear axis and each of these states is affected by an asymmetric perturbation caused by the up and down adjacent states. The rotational-branch intensity and position anomalies in the observed spectra of the nd (1)Delta(g) series (n = 5-8) of Na(2) lead to the conclusion that due to the effects of the L-uncoupling perturbations, the same l complexes approaching the same ion-core limits result in the same l-mixing processes which lead to the formation of the supercomplexes due to the anisotropy of the molecular-ion [Na(2)(+)(3s)] field. This would open up opportunities to study the effects of L uncoupling and perturbations in the nd series and high Rydberg states of other alkali dimers.

14.
J Phys Chem A ; 111(39): 9764-8, 2007 Oct 04.
Article in English | MEDLINE | ID: mdl-17850121

ABSTRACT

The 71Pig Rydberg state of Na2 correlating with the separated atom limit Na(3s) + Na(5p) has been observed using high-resolution cw optical-optical double resonance spectroscopy. A total of 104 identified rovibrational levels in the range v = 0-12 and 11

15.
J Chem Phys ; 123(22): 224303, 2005 Dec 08.
Article in English | MEDLINE | ID: mdl-16375472

ABSTRACT

The phenomenon of electronic orbital angular momentum L uncoupled from its internuclear axis has been observed in the sodium dimer using high-resolution cw optical-optical double-resonance spectroscopy. When L uncoupling occurs, the degeneracy of Lambda doubling is removed. In our experiment, the intermediate B (1)Pi(u) state of Na(2) is excited from the thermally populated ground X (1)Sigma(g) (+) state by a single-line Ar(+) laser. Then, a single-mode dye laser is used to probe the Rydberg states from the intermediate state. The signals are detected by monitoring the UV fluorescence from the triplet gerade states back to the a (3)Sigma(u) (+) state via collision energy transfer. Under our experimental resolution, the splitting of Lambda doubling in the 5 (1)Delta(g) state of Na(2) can be measured. A total of 136 rovibronic levels with ef parities have been assigned to the 5 (1)Delta(g) state. The Lambda-splitting constants deduced from these data are q(0)=0.376(90)x10(-4) cm(-1), q(v)=0.114(6)x10(-4) cm(-1), and mu=0.76(33)x10(-8) cm(-1). In general, the Lambda splitting of the Delta states is considerably smaller than that of the Pi states. However, the first-order splitting constants q(0) and q(v) reported here are larger than those in the B (1)Pi(u) state. This is due to the L uncoupling of the Rydberg states.

16.
J Chem Phys ; 121(21): 10513-8, 2004 Dec 01.
Article in English | MEDLINE | ID: mdl-15549934

ABSTRACT

The doubly excited valence (3p+3p) 2 (1)Delta(g) state of Na(2) is experimentally observed by using optical-optical double resonance spectroscopy. A single line Ar(+) laser (a total of nine lines) was used to pump the sodium dimers from thermally populated ground state X (1)Sigma(g) (+) to the intermediate B (1)Pi(u) state. Then, a single mode Ti:sapphire laser was used to probe the doubly excited 2 (1)Delta(g) state. Violet fluorescence emitted from the highly excited states (mainly 2 (3)Pi(g) or 3 (3)Pi(g) states which are transferred from 2 (1)Delta(g) state via collision) to the a (3)Sigma(u) (+) state was monitored by a filtered photomultiplier tube (PMT). A total of 582 rovibrational levels of 2 (1)Delta(g) state were observed, identified, and assigned to the vibrational and rotational quantum numbers in the range of 0< or =v< or =28 and 11< or =J< or =99, respectively. The absolute vibrational quantum number assignment was verified by comparing the totally resolved fluorescence with the calculated Franck-Condon factors between 2 (1)Delta(g) state and B (1)Pi(u) state. Dunham coefficients and Rydberg-Klein-Rees potential curve were derived from these observed quantum levels. The primary molecular constants of Na(2) 2 (1)Delta(g) state are T(e)=32 416.759(15) cm(-1), omega(e)=124.8484(36) cm(-1), B(e)=0.119 158(3) cm(-1), and R(e)=3.508 20(5) A.

17.
Acta Pharmacol Sin ; 23(6): 503-8, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12060523

ABSTRACT

AIM: To study the effect of yam in Taiwan, which is a commonly used Chinese medicine, on hepato-nephro-toxicity in rats. METHODS: Crude water extract of yam (Dioscorea alata L), was used to treat rats with an acute toxicity induced by acetaminophen (APAP) challenge. RESULTS: The pharmacological and biochemical studies showed the extract of yam had the effect of kidney secureness and liver fortification (P < 0.01). The pathologic sections showed good improvements in renal tubular degranulation changes, necrosis and disintegration. The extract of yam also possessed a good protection against the inflammation of central vein and necrosis of liver tissue. CONCLUSION: The liver and kidneys are originated from the same source. Pathologically, deficiency of the life essence in the kidney may lead to the blood deficiency in the liver. The results showed that the yam could prevent the damages of the liver and kidneys, thus preserving their functions. This could b e the reason why the yam was commonly used in traditional Chinese medicine, as seen in Liuwei Dihuang Wan be used in the case of deficiency of liver-yin and kidney-yin.


Subject(s)
Acetaminophen/adverse effects , Chemical and Drug Induced Liver Injury/pathology , Dioscorea/chemistry , Drugs, Chinese Herbal/pharmacology , Kidney Diseases/pathology , Analgesics, Non-Narcotic/adverse effects , Animals , Chemical and Drug Induced Liver Injury/etiology , Chemical and Drug Induced Liver Injury/prevention & control , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/therapeutic use , Kidney Diseases/chemically induced , Kidney Diseases/prevention & control , Male , Necrosis , Rats , Rats, Wistar , Yin Deficiency/drug therapy
18.
Am J Chin Med ; 30(4): 609-16, 2002.
Article in English | MEDLINE | ID: mdl-12568288

ABSTRACT

Huai-shan-yao (Chinese yam; Rhizome Dioscoreae) is a common food in China. In the present study, we evaluated the protective effects of the crude extract of huai-shan-yao on acute kidney and liver injuries in rats induced by ethanol. Results of pharmacological, biochemical and pathologic observations all showed that rats treated with the extract of huai-shan-yao had decreased damage in renal tubules as well as decreased inflammation in the central vein and necrosis in the liver tissue.


Subject(s)
Dioscorea/chemistry , Drugs, Chinese Herbal/pharmacology , Kidney Diseases/prevention & control , Liver Diseases, Alcoholic/prevention & control , Animals , Antioxidants/pharmacology , Central Nervous System Depressants/toxicity , Ethanol/toxicity , Kidney/pathology , Kidney Diseases/chemically induced , Kidney Diseases/pathology , Kidney Function Tests , Liver/pathology , Liver Diseases, Alcoholic/pathology , Liver Function Tests , Male , Plant Extracts/pharmacology , Plant Roots/chemistry , Rats , Rats, Wistar , Silymarin/pharmacology
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