Nasopharyngeal carcinoma (NPC) is one of the most common malignancies in china, with a deep and hidden
localization. Recently, methods for early diagnosis of NPC has become one of the most important research topics in
medical field. Early monitoring of morphological change of NPC cells during the carcinogenesis is of great importance,
and early information extracted from the NPC cells during the initial stage of NPC is critical for diagnosis and treatment.
In this paper, image processing methods for two-photon microscopic image of NPC cells was investigated with the
purpose of providing useful information for early diagnosis and treatment of NPC.
There is abundant information in a two-photon microscopic image of NPC cells, which can be analyzed and processed
by means of computer and image pattern processing algorithm. In this paper, firstly, a mathematical method of transform
of Bottom-hat based on Matlab platform was employed to enhance the image of NPC cells, making the image easier to
distinguish; Then, several classical edge detection algorithms were compared and discussed, for example, Roberts
operator, Prewitt operator, and Canny operator etc. According to the inherent characteristics of two-photon microscopic
image of NPC cells, corrosion algorithm was used to define the edge of NPC cells. Furthermore, the article gets the
iterative threshold segmentation after noise denoising, on the other hand, improved discriminant analysis was adopted for
threshold segmentation of NPC cells, better results were obtained.
Objective to simulate and model the cells proliferation of Platymonas subcordiformis irradiated by laser, so as to obtain
the quantitative relationship between laser parameters and the effects of mircoalgae irradiated. Methods : Platymonas
subcordiform is irradiated by Nd:YAP(1341 , 10w , 45s--90s);LD(670nm , 800mw , 20min,30min ),Ar+ (532nm,80mw,50Min-65Min) , with 14 dose treatment groups, each 3 samples, and the cells proliferation to be
observed in delay phase of mircoalgae growth, as a data source, and according to the characteristics of growth and
reproduction of single-cell alga in cultured process, Gaussian growth curves are constructed, to fit the samples growth
curve with least squares regression ,and to predict mircoalgae growth trends; on building the linear twin objective
programming model and analyzing by stepwise regression , the laser parameters which is larger correlation with the
numbers of cells proliferation and the rates are screened from all, and a optimal strategy given by model optimization
software (Lingo).Results: By constructing growth curve function, in delay phase, with mircoalgae cells proliferation
accelerating , a single peak Gaussian curve is showed; with inhibited growth the cell numbers trend to reduced, and after
sub-cultivation the numbers significantly upward, then the growth curves meet double-Gaussian function category. There
are goodness of fitting for SSE: 2.383e-005; R-square: 0.9997. It is showed that the parameters of Nd:YAP(1341nm ,
10w,45s) is relatively suitable to accelerate cells proliferation. Conclusions: On mathematical model constructed, in
delay phase of Platymonas subcordiformis, the quantitative relationship is obtained between laser irradiation parameters
and the growing effects to stimulate or to inhibit.
Objective: Auto-fluorescence micro-imaging of microalgae are observed by using of laser scanning confocal microscopy (LSCM) and fluorescence microscopy, so as to investigate the effect of auto fluorescence alteration on growth of irradiated microalgae irradiated, meanwhile, the method of microalgae cells stained also to be studied. Methods: Platymonas subcordiformis, Phaeodactylum tricormutum and Isochyrsis zhanjiangensis cells are stained with acridine orange, and observed by fluorescence microscopy; the three types microalgae mentioned above are irradiated by Nd:YAP laser with 10w at 1341nm, irradiating time:12s, 30s, 35s and 55s, than to be cultured 6 days, and the auto fluorescence images and fluorescence spectra of algae cells are obtained by LSCM on lambda scan mode, at excitation 488nm (Ar+ laser). Results: It is showed that the shapes and the structural features of microalgae cells stained can be seen clearly, and the cytoplasm and nucleus also can be observed. The chloroplasts in cell is bigger on promoting effects, conversely, it is to be mutilated, deformation and shrink. Contrast to the CK, the peak positions of fluorescence of algae cells irradiated is similar to the whole while the peak light intensity alters. On irradiation of promoting dose, however, the auto fluorescence intensity is enhanced more than control. Conclusions: The method of cell stained can be used to observed genetic material in microalgae. There are obvious effects for laser irradiating to chloroplasts in cells, the bigger chloroplasts the greater fluorescence intensity. Physiological incentive effects of microalgae irradiated can be given expression on fluorescence characteristics and fluorescence intensity alteration of cells.
In this present paper, the microalgae irradiated by Nd:YAP laser are observed using Laser Confocal Scan microscope,
and the auto fluorescence of microalgae cells is analyzed with quantitative analysis system, so as to investigate the effect
of auto fluorescence alteration on growth of irradiated microalgae. Method: Platymonas subcordiformis, Phaeodactylum
tricormutum and Isochyrsis zhanjiangensis are irradiated by Nd:YAP laser with 10w at 1341nm, irradiating time:12s, 30s,
35s and 55s. On Lambda Scan mode, the auto fluorescence images and fluorescence spectra of algae cells are obtained
by the excitation 488nm (Ar+ laser). Result: there are two summit peaks, 489.8nm and 680.9nm, for Platymonas
subcordiformis, Phaeodactylum tricormutum and Isochyrsis zhanjiangensis fluorescence spectrum. Contrast to the CK,
the peak positions of fluorescence of irradiated algae cells is similar to the whole while the peak light intensity alters. On
irradiation of promoting dose, however, the auto fluorescence intensity is enhanced more than control, with different type
of microalgae, the different fluorescence intensity are shown in the analysis, and all of the microalgae pigment bodies
change can be seen also. Conclusion: Physiological incentive effect of irradiated microalgae can be given expression on
fluorescence characteristics and fluorescence intensity alteration of cells.
Raman spectrum of Platymonas subcordiformis was studied by FT-Raman spectroscopy. The results show that the
optimum experiment conditions is that making sample lose solvent with centrifuge, excitation laser power for 360mW
and accumulating 70 times. The main peaks of the spectrum are located at 556cm-1, 615cm-1, 880cm-1, 960 cm-1, 1112cm-1, 1457cm-1, 1523cm-1, 2986cm-1, respectively. These peaks can be assigned to protein, instauration acid and
ester, etc., which are the main compositions of Platymonas subcordiformis. The precise measurements of algae Raman
Spectroscopy could be used for biological samples research, such as developing a new optical taxonomic methodology
to distinguish different algae species, and a rapid, non-destructive detection way of stress effects.
In this present paper, dry seeds of peanut of cytological effects and agro-character in F1 generation have been studied for YAG laser-irradiated at 1060 nm. With transmission electron microscope, the effects of ultrastructure of plumule cell were observed. There were difference in the cell on membrane system, fatbody and nucleus, especially in proteinbody, and there was chromosomal aberration of peanut root tip cell induced with laser 35.84w/cm2 power density. With irradiating time added from3s to 8s the rate of aberration increased from 0.16% up to 0.53%, and the types of chromosomal aberration also increased. Many aberration types, such as earlier separated mitosis metaphase, variability of number, sticky, non-equal division, polypolarity division, nucleus protrudes to cytoplasm and so on were found in 8s treatment but not in 3s. However, the dose of 8s treatment leads to lethal dose according to the seeds sprouting and growing. The seeds with 3s treatment, mine stem height, total pods per plant, mature pods per plant and weight per plant were more than the seeds unirradiated.
After semiconductor laser irradiation on dry seeds of peanut with 0.25w/cm2 X 300s, 480s, at 650nm ,the effects of ultrastructures of plumule cell and chromosomal aberration have been studied in the present paper. The results showed many aberration types, such as earlier separated mitosis metaphase, variability of number, sticky, chromosomal laggards and ioop and so on were found in treatment group. With H-600 transmission electron microscope, the effects of ultrastructures of plumule cell were observed. There were difference in the cell on membrane system, fatbody and nucleus, especially in proteinbody. In this experiment, the sprout of peanut seeds( irradiated by semiconductor laser 0.25w/cm2x300s, 480s, 650nm) and generation agro-character also have been researched.
This paper reports the biological effect and the laser parameter of laser induced mutation in the peanut seeds. Peanut seed were irradiated with laser Ar+ at 488nm, LD at 650nm and YAG at 1060nm. There were different dose from 0.128w/cm2 x 180s to 35.84w/cm2 x 3s. The ultrastructural of plumule cell of peanut seed irradiated were examined by transmission electron microscopy, and the agro-character of M1 peanut were observed. The result shows that different laser with lower dose can promote the peanut seeds growth; to get the same irradiating effect as shorter wavelength laser, long wavelength laser should be increased does; on the same irradiation does condition, the biological effect related to power density and time combined. With irradiation dose increased, the cells structure were destroyed seriously and the rates of seedling lethality increased.
The S. flexnesi, which have high drug-resistance especially in Cm, Sm, Tc, SD, were irradiated by Ar+ laser at 488 nm and semiconductor laser at 808 nm. The experiment results have shown that both Ar+ laser and semiconductor laser with power density of 1.7 w/cm2 and irradiation dose of 2000 J/cm2 can conduce to the bacterial lethality and increase the mutation rates of the bacterial drug-sensitivity, and 'Colony Count' method have the superiority over the 'Inhibacteria Ring' method. At the mean time it further indicate that the high power semiconductor laser would play an important role in the sciences of laser biological medicine. But the effect of the near infrared semiconductor laser is far lower than that of Ar+ laser of shorter wavelength at the same irradiation dose. It is clear that the output and irradiation dose of near infrared semiconductor laser shall be increased in order to get the same rates of the bacterial lethality and the drug-sensitivity mutation as Ar+ laser's.