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This article describes the application of Raman spectroscopy to quantitatively measure the concentration of crystal violet using acetonitrile as the internal standard. Band intensity ratios of crystal violet to acetonitrile, [...]

Polypyrrole (PPy) is easy-prepared with good biocompatibility and strong absorption in near-infrared (NIR) region which can serve as both the photothermal therapeutic agent and contrast agent of optical coherence tomography (OCT) imaging. Herein, gold nanorod (GNR) modified with PPy (GNR-PPy) as contrast agent for optical coherence tomography imaging was investigated. GNR-PPy was synthesized via one-pot facile oxidative polymerization by using pyrrole and GNR as starting materials. Nanoparticles were characterized using ultraviolet-visible absorbance spectroscopy, Raman spectroscopy and transmission electron microscopy. A xenograft tumor mouse model was fabricated to study the OCT contrast effect of GNR-PPy on breast tumor. An OCT system equipped with an 840 nm SLED was used for OCT imaging of the tumors injected with gold nanostructures. The experimental results indicated that the penetration depth of the OCT signals from tumors injected with GNR-PPy was lower than that from tumors injected with gold nanorods, which could be ascribed to the stronger light activity of GNR-PPy in NIR region. To quantitatively analyze the contrast effect, the attenuation coefficients were extracted from the OCT images of tumors injected with the nanostructures. In comparison with the attenuation coefficient extracted from the OCT images containing GNR, the attenuation coefficient of tumors injected with GNR-PPy was significant higher. It was concluded that gold nanorods modified with polypyrrole can enhance the light absorption in near-infrared much better, which would provide a possible detection means for enhancing the contrast effect of tumor tissues.

In the present paper, we have successfully synthesized silver nancomparticles by reducing of silver nitrate in alkaline solution via 60 degrees C water bath for 20 minutes with the use of tyrosine, a nontoxic and green macromolecule, as a reducing and stabilizing agent. The formation of silver nanoparticles was observed visually by color change of the solutions (from faint yellow to brown yellow). The morphologies of the Ag NPs were characterized by UV-Vis absorption spectroscopy and transmission electron microscopy (TEM). The UV-Vis absorption peak of silver nanoparticles located at 412 nm. The TEM image of silver nanoparticles indicated that the diameters of nanospheres are mainly in the range 15-25 nm. In order to evaluate the SERS activity of the silver nancomparticles, crystal violet and folic acid were used as the Raman probe molecule. The experimental results indicated that there are two ascendancies, firstly, the approach is convenient and the reaction condition is facile, secondly, tyrosine is a water-soluble, nontoxic and biodegradable macromolecule, which makes this approach provide a green strategy to prepare Ag NPs. Significantly, the synthesized Ag NPs exhibits good surface enhanced Raman scattering (SERS) activity as SERS substrates to detect crystal violet and folic acid in aqueous solution.

Characteristics and differences of temperature and back-scattered light intensity in different depths of 0.2, 0.4, 0.6, 0.8 and 1 mm for both human Hegu acupoint and non-acupoint tissue irradiated by 808 nm diode laser at the different power of 15, 25 and 35 mW were studied. The temperature and the back-scattered light intensity in different depths of 0.2, 0.4, 0.6, 0.8 and 1 mm for human Hegu acupoint and non-acupoint tissue were measured by using the infrared thermography and optical coherence tomography. The result shows few differences in the temperature and the back-scattered light intensity of human Hegu acupoint and non-acupoint tissue before irradiation. The temperature and back-scattered light intensity of Hegu acupoint and the non-acupoint after irradiation were significantly higher, and the temperature and back-scattered light intensity of Hegu acupoint significantly were higher than the non-acupoint areas. At 0-40 min after the irradiation, the temperature and back-scattered light intensity of Hegu acupoint and the non-acupoint area will fluctuate and gradually decrease with the passage of time. From the results above, it is clearly seen that Hegu acupoint is different from non-acupoint both in the back-scattered light intensity and temperature after irradiation, and Hegu acupoint is more sensitive to laser irradiation than non-acupoint tissue.

Raman spectroscopy was used to study the influence of ultraviolet-A(UV-A) radiation on collagen I. The Raman spectra of collagen I and that after 90 min UV-A radiation were reported. The results proved that irradiation with 90 min UV-A caused the change in the structures of collagen I. Intramolecular hydrogen bonds were broken, and the hydrogen bonding system was changed. The intensity of helix was decreased, while the intensity of the disordered conformation in proteins such as random coil was increased. Otherwise, the UV-A radiation influenced the hydroxylation of proline and the content of hydroxyproline was reduced. The changes caused by UV-A radiation could damage the triple helical structure of collagen I. It would lead to a series of changes, such as the destruction of collagen fibers during the photoaging of skin.

The changes of skin tissue reflectance spectroscopy before and after being treated with the optical clearing agents of three different types of optical clearing within the wavelength rang of 400-1 000 nm, and the degree of changes in reflectance spectroscopy of each group skin during 0-60 min at 580 nm in vivo were real-time dynamically researched. The reflectance spectroscopy of skin tissue before and after being dealt by the optical clearing agents of glycerol, glucose and propylene glycol was measured using a USB-4000 fiber spectrophotometer at 0, 10, 20, 30, 40, 50 and 60 min. The results showed that the reflectance spectral intensity was distinctly decreased, but the reflectance was significantly increased gradually with the time prolonged. However, different optical clearing agents have different clearing progress. The relative decrease of reflectance of palm skin tissue before and after being dealt by the optical agents of 40% glycerol, 40% glucose and 40% propylene glycol during 10, 20, 30, 40, 50 and 60 min at the wavelength 580 nm is 5%, 7%, 9%, 10%, 11% and 12%, 9%, 13%, 16%, 19%, 21% and 22%, and 14%, 22%, 29%, 32%, 34% and 35%, respectively. The significant improvement in light transmittance and enhancement of light penetration through tissue was demonstrated for all solutions. The effect and processes of optical clearing of skin tissue is not only closely related to the choosing of the clearing agent type, but also related to the treatment time with the skin tissue. The clearing progress of different type optical clearing agent showed the order of 40% propylene glycol, 40% glucose and 40% glycerol.

Acupoint was reaction of viscera and its optical parameter was an important characteristic of tissue. In the present work, in order to discuss specificity of acupuncture on the response of qi and blood in human body, we compared the diffuse reflectance of Taichong (LV3), Taibai (SP3), and Chongyang (ST42) before, during and after menstruation. All the acupoints had the same shape of the spectrum and troughs were all at 423.16, 544.06 and 577.47 nm. The values of reflectance during menstruation were greater than before and after menstruation, especially for SP3 and ST42 (P < 0.05). SP3 and ST42 were more sensitive to the changes of qi and blood than LV3, and it was asymmetric and we found no evidence for the imbalance of the left side and right. These results indicated that acupoint diffuse reflectance changed with qi and blood, and that SP3 and ST42 had close relationship with menstruation. Diffuse reflectance may be possibly used in the quantitative analysis of qi and blood.

Objective: To compare the effect and safety evaluation of catgut implantation at acupoint and drugs for levels of bone metabolism and free radicals in postmenopausal women., Methods: Sixty-five postmenopausal women were randomly divided into an acupoint catgut implantation group (33 cases) and a medication group (32 cases). Sanyinjiao (SP 6), Shenshu (BL 23) and Guanyuan (CV 4) were used as main points combined with adjunct points according to syndrome differentiation in the acupoint catgut implantation group, once two weeks. The medication group was treated with oral administration of 2 pills of Fu fuchun capsule, once a day. Three months constitute one course in the both groups. The scores of the symptoms and signs were evaluated, and elbow vein blood was drawn to detect the correlative index on the beginning and the ending day of the treatment respectively. The safety of catgut implantation at acupoint was evaluated after one course of treatment. Besides, the sex hormone test in ovulatory period was detected in twenty-eight normal women in reproductive age with regular menstrual cycle., Results: 1) The total effective rate of the acupoint catgut implantation group was 93.9% (31/33), and that of the medication group was 96.9% (31/32), there was no significant difference between the two groups (P>0.05). The contents of bone gla protein (BGP), calcitonin (CT), parathyroid hormone (PTH) and alkaline phosphatase (AKP) in the both groups had significant differences after treatment (P<0.05, P<0.01); 2) The content of estradiol (E2) in serum in the both groups was decreased more obviously than those of normal women in reproductive age (both P<0.001). The content of E2 in the both groups was obviously increased after treatment (P<0.05, P<0.01), this function in the acupoint catgut implantation group was weaker than that of the medication group (P<0.05), while the incidence rate of adverse effect in the acupoint catgut implantation group was lower than that of the medication group (P<0.05); 3) There were significant differences of the level of superoxide dismutase (SOD) and malondialdehyde (MDA) before and after treatment in the acupoint catgut implantation group, the level of SOD was obviously increased after treatment (P<0.01), while the level of MDA decreased obviously (P<0.001)., Conclusion: Catgut implantation at acupoint can improve the low level of estrogen of postmenopausal women, with good safety. It can regulate the levels of bone metabolism and free radicals of postmenopausal women, so it is very meaningful to prevent and treat postmenopausal degenerative diseases including the osteoporosis and to delay the process of apolexis.

In order to find a non-invasive way to improve the efficacy of skin optical clearing with topically applied optical clearing agents, the authors researched the changes of reflectance spectroscopy of skin tissues before and after being dealt by low-frequency ultrasound and osmotic active chemical agents within the wavelength range of 400-860 nm, and the degree of changes in reflectance spectroscopy of each group skin during 0-15 min and 15-30 min at 580 nm. The measurements were performed using a AvaSpec-2048 optical fiber spectrometer with integrating-sphere setup. The results of measurements showed that there were a few changes of the reflectance spectroscopy of skin tissues in the control group (Group 1) (The skin tissue was dealt with nothing. ) during the whole observation; But in the Group 2 (The skin tissue was dealt with only low-frequency ultrasound), it was found that the reflectance of the skin tissue showed a significant increase comparing 15 min with 0 min, but the changes in reflectance of the tissues slowly restored the original form following the longer time since the ultrasound stopping; There was also a very fast changes in reflectance of the skins in the Group 3 (the skin were dealt with only 80% glycerol) compared with that in the Group 1. The authors also found that there was a very distinct decrease in the reflectance of skin tissues dealt with both low-frequency ultrasound and 80% glycerol group (Group 4), especially during the 0-15 min, and its speed was 4.0 times that of the Group 1 and 2. 3 times that of Group 3 (During 0-15 min, the reflectance of skin tissues in the Group 1 decreased 1.896%; the reflectance of skin tissue in the Group 3 decreased 3.316%; the reflectance of skin tissues in the Group 4 decreased 7.551%). From the above results, it can be clearly seen that the low-frequency ultrasound and 80% glycerol not only have synergistic effect on optical clearing of skin tissue in vitro, but can change the optical clearing of the skin tissue in a short time.

Characteristics and differences of reflectance spectroscopy of human Laogong acupoint and non-acupoint tissues before and after irradiation by different power of laser were studied in the spectral range from 400 to 1 000 nm. A wavelength 808 nm semiconductor laser was used for irradiation at the power of 20, 50 and 100 mW for ten minutes. Reflectance spectra of human Laogong acupoint and non-acupoint tissues were measured by using an AvaSpec-2048 optical fiber spectroscopy with an integrating sphere attachment. The result shows that before irradiation the shape of the reflectance spectra of Laogong acupoint and non-acupoint is similar, they have the same troughs at 423, 544, 577 and 980 nm, and the reflectance for Laogong acupoint and non-acupoint at these wavelengths is 17.1%, 26.1%, 25.9% and 35.0%, and 17.1%, 27.6%, 28.1% and 36.5% respectively. But from 475 to 1 000 nm, the reflectance of Laogong acupoint is smaller than that of non-acupoint. After being irradiated by semiconductor laser at the power of 20, 50 and 100 mW, there is a very significant decrease in the reflectance of Laogong acupoint compared to that before irradiation, and the higher the power, the lower the reflectance. But there is just a small decrease in the reflectance for non-acupoint compared to that before irradiation. From the above results, it is clearly seen that Laogong acupoint is different from non-acupoint on reflectance spectroscopy, and Laogong acupoint is more sensitive to laser irradiation than non-acupoint tissue.

Differential diagnosis for epithelial tissues of normal human gastric, undifferentiation gastric adenocarcinoma, gastric squamous cell carcinomas, and poorly differentiated gastric adenocarcinoma were studied using the Kubelka-Munk spectral function of the DNA and protein absorption bands at 260 and 280 nm in vitro. Diffuse reflectance spectra of tissue were measured using a spectrophotometer with an integrating sphere attachment. The results of measurement showed that for the spectral range from 250 to 650 nm, pathological changes of gastric epithelial tissues induced that there were significant differences in the averaged value of the Kubelka-Munk function f(r infinity) and logarithmic Kubelka-Munk function log[f(r infinity)] of the DNA absorption bands at 260 nm between epithelial tissues of normal human stomach and human undifferentiation gastric cancer, between epithelial tissues of normal human stomach and human gastric squamous cell carcinomas, and between epithelial tissues of normal human stomach and human poorly differentiated cancer. Their differences were 68.5% (p < 0.05), 146.5% (p < 0.05), 282.4% (p < 0.05), 32.4% (p < 0.05), 56.00 (p < 0.05) and 83.0% (p < 0.05) respectively. And pathological changes of gastric epithelial tissues induced that there were significant differences in the averaged value of the Kubelka-Munk function f(r infinity) and logarithmic Kubelka-Munk function log[f(r infinity)] of the protein absorption bands at 280 nm between epithelial tissues of normal human stomach and human undifferentiation gastric cancer, between epithelial tissues of normal human stomach and human gastric squamous cell carcinomas, and between epithelial tissues of normal human stomach and human poorly differentiated cancer. Their differences were 86.8% (p < 0.05), 262.9% (p < 0.05), 660.1% (p < 0.05) and 34% (p < 0.05), 72. 2% (p < 0.05), 113.5% (p < 0.05) respectively. And pathological changes of gastric epithelial tissues induced that there were significant differences in the averaged value of the Kubelka-Munk function f(r infinity) and logarithmic Kubelka-Munk function log[f(r infinity)] of the carotene absorption bands at 480 nm between epithelial tissues of normal human stomach and human undifferentiation gastric cancer, between epithelial tissues of normal human stomach and human gastric squamous cell carcinomas, and between epithelial tissues of normal human stomach and human poorly differentiated cancer. Their differences were 59.5% (p < 0.05), 73% (p < 0.05), 258.9% (p < 0.05), 118.7% (p < 0.05), 139.2% (p < 0.05), and 324. 6% (p < 0.05) respectively. It is obvious that pathological changes of gastric epithelial tissues induced that there were significant changes in the contents of the DNA, protein and beta-carotene of gastric epithelial tissues. The conclusion can be applied to rapid, low-cost and noninvasive the optical biopsy for gastric cancer and provides a useful reference.

Differential diagnosis of human colon adenoma was studied using the Kubelka-Munk spectral function of the DNA and protein absorption bands at 260 and 280 nm in vitro. Diffuse reflectance spectra of tissue were measured using a spectrophotometer with an integrating sphere attachment. The results of measurement showed that for the spectral range from 590 to 1 064 nm pathological changes of colon epithelial tissues were induced so that there were significant differences in the averaged values of the Kubelka-Munk function f(r infinity) and logarithmic Kubelka-Munk function log [f(r infinity)] of the DNA absorption bands at 260 nm between normal and adenomatous colon epithelial tissues, and the differences were 218% (p < 0.05) and 68.5% (p < 0.05) respectively. Pathological changes of colon epithelial tissues were induced so that there were significant differences in the averaged values of the Kubelka-Munk function f(r infinity) and logarithmic Kubelka-Munk function log [f(r infinity)] of the protein absorption bands at 280 nm between normal and adenomatous colon epithelial tissues, and the differences were 208% (p < 0.05) and 59.0% (p < 0.05) respectively. Pathological changes of colon epithelial tissues were induced so that there were significant differences in the averaged values of the Kubelka-Munk function f(r infinity) and logarithmic Kubelka-Munk function log [f(r infinity)] of the beta-carotene absorption bands at 480 nm between normal and adenomatous colon epithelial tissues, and the differences were 41.7% (p < 0.05) and 32.9% (p < 0.05) respectively. Obviously, pathological changes of colon epithelial tissues were induced so that there were significant changes in the contents of the DNA, protein and beta-carotene of colon epithelial tissues. The conclusion can be applied to rapid, low-cost and noninvasive optical biopsy of colon adenoma, and provides a useful reference.

Functional magnetic resonance imaging (fMRI) was used to study the activated brain areas of human during simple and complex digital calculation, and to investigate the role of cortical and subcortical structures involved in the mental calculation. Sixteen right-handed healthy volunteers performed mental calculation of simple and complex addition/subtraction respectively, while the fMRI data were recorded by a Seimens 1.5 T MR machine. Block-design was used in the tasks. Two calculation tasks and one base-line tasks were performed for the block-design. Simple calculation task was single-digit addition and subtraction, while the complex was multi-digit addition and subtraction. The base-line task was to tell whether the two numbers were the same in every trial. Statistical parametric mapping (SPM99) was employed to process data and localize functional areas. We compared the average activation intensity of each activated brain regions in the same calculation task and the activation intensity of the same regions in both tasks respectively. Both the cortex and the subcortical structures including basal ganglia and thalamus were activated during simple and complex mental calculations. Similar brain regions in subjects including frontal lobe, parietal lobe, occipital lobe, cingulate gyrus, thalamus and cerebellum were engaged in simple and complex addition/subtraction. In the same task, activation intensity of all activated brain areas differed insignificantly. Compared with the complex task, the right parietal lobe was not activated in the simple one. The subcortical structures such as the caudate nucleus and the left marginal division of the striatum (MrD) were activated in both two calculation tasks. The cortical regions involved in both simple and complex addition/subtraction were similar. In conclusion, both the cortex and the subcortical structures were activated during the mental calculation. The cortex including the frontal cortex, parietal cortex, and cingulate gyrus were activated during mental calculation, while the subcortical structures such as the caudate nucleus, the globus pallidum and the left marginal division of the striatum also played a critical role in the neural networks of the calculation at the same time. Right parietal lobe (supramarginal gyrus) was engaged only in the complex task, which suggested that this region might be involved in the visuospatial memory and processing.

A double-integrating-spheres and IAD method were used to study the differences in the optical penetration depths (OPDs) and light attenuation (LA) native and coagulated human liver tumors and liver tissues at the wavelengths of 680, 720, 780, 810, 850 and 890 nm of Ti: Sapphire laser. The results of measurement showed that the OPDs for native and coagulated human liver tumors and liver tissues at six different wavelengths obviously increase with increasing laser wavelength, the OPDs of coagulated human liver tumors and liver tissues at six different wavelengths were significantly smaller than that of native human liver tumors and liver tissues at the same wavelength respectively (P<0.05), and the OPDs of native and coagulated human liver tumors at six different wavelengths were significantly bigger than that of native and coagulated human liver tissues at the same wavelength respectively (P<0.05). The LA for native and coagulated human liver tumors and liver tissues at six different wavelengths obviously decreases with increasing laser wavelength, and the LA for coagulated human liver tumors and liver tissues at six different wavelengths is significantly bigger than that for native human liver tumors and liver tissues at the same wavelength respectively (P<0.05). The LA for native and coagulated human liver tumors at six different wavelengths is significantly bigger than that for native and coagulated human liver tissue at the same wavelength respectively (P<0.05).

Raman spectroscopy was used to investigate the effect of different intervals of ultraviolet (UV) to calf thymus DNA in aqueous solution. At the same time, the different influences of these three UV parts were compared, and a complete damaging mechanism of UV to DNA was obtained. The results showed that UVC damages DNA in a complete way, while UVA and UVB damage DNA in a selective way, and the speed effect of UVB on DNA was faster than that of UVA. UVC seemed to be less valid in reducing the B conformation of DNA than UVA and UVB. Among all the groups of DNA, the pyrimidine bases and the deoxyribose experienced the most severe damages. Moreover, with UVA or UVB irradiation for 3 h, the photoreactivation of DNA occured. The experimental results partly supported the formation of several types of dimeric lesions between adjacent pyrimidine bases, most notably cyclobutane pyrimidine dimers (CPD), 6-4 photoproducts (6-4PP) and the Dewar valence isomers.

The lanthanide trivalence ion and its chelates are used for marking substance in Time-Resolved Fluorescence Immunoassay (TRFIA), marking protein, hormone, antibody, nucleic acid probe or biologic alive cell, to measure the concentration of the analysis substance inside the reaction system with time-resolved fluorometry after the reaction system occurred, and attain the quantitative analysis's purpose. TRFIA has therefore become a kind of new and more sensitive measurement method after radioisotope marking, enzymatic marking, chemiluminescence, electrochemiluminescence, primarily depending on the special physics and chemistry characteristics of lanthanide trivalence ion and its chelates. In this paper, the result of spectroscopic evaluation of europium trivalence ion and its chelate, and the principle of time-resolved technology and fluorescence-enhanced technology are reported. At the same time, the experiment shows that the excitation wavelength chosen between 336 and 337 nm benefits the excitation and the energy transfer of chelate diketone of europium trivalence ion.