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1.
Genet Mol Res ; 14(3): 11126-32, 2015 Sep 22.
Article in English | MEDLINE | ID: mdl-26400343

ABSTRACT

The aim of this study was to evaluate the role of GSTM1 null/present, GSTT1 null/present, and GSTP1 IIe105Val polymorphisms in the clinical response to chemotherapy and treatment outcome of patients with breast cancer. A total of 262 subjects were randomly selected from among patients with a histologically confirmed breast cancer. The genotypes of GSTM1, GSTT1, and GSTP1 IIe105Val polymorphisms were determined by polymerase chain reaction-restriction fragment length polymorphism analysis. Our study found that the null genotype of GSTM1 was associated with a better response to chemo-therapy, and the odds ratio [95% confidence interval (CI)] was 1.78 (1.03-3.08). In the Cox proportional hazard model, the hazard ratio (95%CI) for overall survival (OS) in patients carrying the null genotype of GSTM1 was 0.57 (0.32-0.98) using the non-null genotype as the reference variable. However, we observed no significant association between the GSTT1 and GSTP1 polymorphisms and response to chemotherapy and OS in patients with breast cancer. In conclusion, our study found that the GSTM1 polymorphism plays an important role in influencing the chemotherapy response and OS in patients with breast cancer.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/genetics , Glutathione S-Transferase pi/genetics , Glutathione Transferase/genetics , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Breast Neoplasms/drug therapy , Breast Neoplasms/mortality , Docetaxel , Female , Genetic Association Studies , Humans , Kaplan-Meier Estimate , Middle Aged , Polymorphism, Single Nucleotide , Proportional Hazards Models , Taxoids/administration & dosage , Thiotepa/administration & dosage , Treatment Outcome
2.
Braz. j. med. biol. res ; 47(9): 759-765, 09/2014. tab, graf
Article in English | LILACS | ID: lil-719322

ABSTRACT

The monoamine serotonin (5-hydroxytryptamine, 5-HT), a well-known neurotransmitter, also has important functions outside the central nervous system. The objective of this study was to investigate the role of 5-HT in the proliferation, differentiation, and function of osteoblasts in vitro. We treated rat primary calvarial osteoblasts with various concentrations of 5-HT (1 nM to 10 µM) and assessed the rate of osteoblast proliferation, expression levels of osteoblast-specific proteins and genes, and the ability to form mineralized nodules. Next, we detected which 5-HT receptor subtypes were expressed in rat osteoblasts at different stages of osteoblast differentiation. We found that 5-HT could inhibit osteoblast proliferation, differentiation, and mineralization at low concentrations, but this inhibitory effect was mitigated at relatively high concentrations. Six of the 5-HT receptor subtypes (5-HT1A, 5-HT1B, 5-HT1D, 5-HT2A, 5-HT2B, and 5-HT2C) were found to exist in rat osteoblasts. Of these, 5-HT2A and 5-HT1B receptors had the highest expression levels, at both early and late stages of differentiation. Our results indicated that 5-HT can regulate osteoblast proliferation and function in vitro.


Subject(s)
Animals , Calcification, Physiologic/drug effects , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Osteoblasts/drug effects , Serotonin/pharmacology , DNA Primers , Gene Expression , Osteoblasts/cytology , Osteoblasts/metabolism , Primary Cell Culture , Rats, Sprague-Dawley , Real-Time Polymerase Chain Reaction , Receptors, Serotonin/metabolism , Serotonin/metabolism
3.
Braz J Med Biol Res ; 47(9): 759-65, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25098615

ABSTRACT

The monoamine serotonin (5-hydroxytryptamine, 5-HT), a well-known neurotransmitter, also has important functions outside the central nervous system. The objective of this study was to investigate the role of 5-HT in the proliferation, differentiation, and function of osteoblasts in vitro. We treated rat primary calvarial osteoblasts with various concentrations of 5-HT (1 nM to 10 µM) and assessed the rate of osteoblast proliferation, expression levels of osteoblast-specific proteins and genes, and the ability to form mineralized nodules. Next, we detected which 5-HT receptor subtypes were expressed in rat osteoblasts at different stages of osteoblast differentiation. We found that 5-HT could inhibit osteoblast proliferation, differentiation, and mineralization at low concentrations, but this inhibitory effect was mitigated at relatively high concentrations. Six of the 5-HT receptor subtypes (5-HT1A, 5-HT1B, 5-HT1D, 5-HT2A, 5-HT2B, and 5-HT2C) were found to exist in rat osteoblasts. Of these, 5-HT2A and 5-HT1B receptors had the highest expression levels, at both early and late stages of differentiation. Our results indicated that 5-HT can regulate osteoblast proliferation and function in vitro.


Subject(s)
Calcification, Physiologic/drug effects , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Osteoblasts/drug effects , Serotonin/pharmacology , Animals , DNA Primers , Gene Expression , Osteoblasts/cytology , Osteoblasts/metabolism , Primary Cell Culture , Rats, Sprague-Dawley , Real-Time Polymerase Chain Reaction , Receptors, Serotonin/metabolism , Serotonin/metabolism
4.
Phys Rev Lett ; 109(1): 013602, 2012 Jul 06.
Article in English | MEDLINE | ID: mdl-23031104

ABSTRACT

We experimentally and theoretically study the coincidence count rate for down-converted x-ray photons. Because of photoionization, parametric down-conversion at x-ray wavelengths generally involves loss and the theoretical description requires a Langevin approach. By working in a transmission geometry (Laue) rather than in the Bragg geometry of previous experiments, we obtain an improvement in the signal-to-noise ratio of 12.5, and find agreement between experiment and theory.

5.
Phys Rev Lett ; 104(22): 223601, 2010 Jun 04.
Article in English | MEDLINE | ID: mdl-20867167

ABSTRACT

We describe a proof-of-principal experiment demonstrating the use of spread spectrum technology at the single photon level. We show how single photons with a prescribed temporal shape, in the presence of interfering noise, may be hidden and recovered.

6.
Phys Rev Lett ; 104(25): 253602, 2010 Jun 25.
Article in English | MEDLINE | ID: mdl-20867376

ABSTRACT

We describe an experiment demonstrating the radarlike technique of "chirp and compress." Chirped biphotons are generated using a quasi-phase-matched nonlinear crystal where the phase-matched frequency varies linearly with position. Sum frequency generation is used to measure the amplitude of the biphoton wave function. As compared to a nonchirped crystal, compression and an increase in summing efficiency of a factor of 5 is observed.

7.
J Bone Joint Surg Br ; 92(9): 1282-8, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20798449

ABSTRACT

This study prospectively compared the efficacy of kyphoplasty using a Jack vertebral dilator and balloon kyphoplasty to treat osteoporotic compression fractures between T10 and L5. Between 2004 and 2009, two groups of 55 patients each underwent vertebral dilator kyphoplasty and balloon kyphoplasty, respectively. Pain, function, the Cobb angle, and the anterior and middle height of the vertebral body were assessed before and after operation. Leakage of bone cement was recorded. The post-operative change in the Cobb angle was significantly greater in the dilator kyphoplasty group than in the balloon kyphoplasty group (-9.51 degrees (sd 2.56) vs -7.78 degrees (sd 1.19), p < 0.001)). Leakage of cement was less in the dilator kyphoplasty group. No other significant differences were found in the two groups after operation, and both procedures gave equally satisfactory results in terms of all other variables assessed. No serious complications occurred in either group. These findings suggest that vertebral dilator kyphoplasty can facilitate better correction of kyphotic deformity and may ultimately be a safer procedure in reducing leakage of bone cement.


Subject(s)
Fractures, Compression/surgery , Spinal Fractures/surgery , Vertebroplasty/instrumentation , Aged , Aged, 80 and over , Female , Fracture Fixation/instrumentation , Fracture Fixation/methods , Fractures, Compression/diagnostic imaging , Humans , Male , Middle Aged , Osteoporosis/complications , Prospective Studies , Radiography , Spinal Fractures/diagnostic imaging , Spinal Fractures/etiology , Vertebroplasty/methods
8.
Phys Rev Lett ; 103(16): 163601, 2009 Oct 16.
Article in English | MEDLINE | ID: mdl-19905694

ABSTRACT

We demonstrate a new type of quantum mechanical correlation where phase modulators at distant locations, acting on the photons of an entangled pair, interfere to determine the apparent depth of modulation. When the modulators have the same phase, the modulation depth doubles; when oppositely phased, the modulators negate each other.

9.
Phys Rev Lett ; 102(5): 053602, 2009 Feb 06.
Article in English | MEDLINE | ID: mdl-19257512

ABSTRACT

We describe a technique for enhancing the efficiency of sum frequency generation using entangled signal and idler photons. By resonating the sum frequency field, we observe that the generated power varies linearly with input power and is increased by a factor of 12.

10.
Phys Rev Lett ; 101(10): 103601, 2008 Sep 05.
Article in English | MEDLINE | ID: mdl-18851214

ABSTRACT

We use the Stokes photon of a biphoton pair to set the time origin for electro-optic modulation of the wave function of the anti-Stokes photon thereby allowing arbitrary phase and amplitude modulation. We demonstrate conditional single-photon wave functions composed of several pulses, or instead, having Gaussian or exponential shapes.

11.
Opt Lett ; 33(18): 2149-51, 2008 Sep 15.
Article in English | MEDLINE | ID: mdl-18794960

ABSTRACT

We describe the observation of a sharp leading-edge spike in a biphoton wave packet that is produced using slow light and measured by two-photon correlation. Using the stationary-phase approximation we characterize this spike as a Sommerfeld-Brillouin precursor resulting from the interference of low- and high-frequency spectral components.

12.
Phys Rev Lett ; 100(18): 183603, 2008 May 09.
Article in English | MEDLINE | ID: mdl-18518372

ABSTRACT

This Letter describes the generation of biphotons with a temporal length that can be varied over the range of 50-900 ns, with an estimated subnatural linewidth as small as 0.75 MHz. We make use of electromagnetically induced transparency and slow light in a two-dimensional magneto-optical trap with an optical depth as high as 62. We report a sharp leading edge spike that is a Sommerfeld-Brillouin precursor, as observed at the biphoton level.

13.
Phys Rev Lett ; 98(5): 053601, 2007 Feb 02.
Article in English | MEDLINE | ID: mdl-17358855

ABSTRACT

We find that in a two-level system there are two kinds of four-wave mixing processes which destructively contribute to the third-order nonlinear susceptibility. In a paired-photon generation scheme by using a single retroreflected pump beam, these two processes occur with definite time orders. The biphoton temporal correlation, which is measured with a back-to-back geometry in a laser-cooled two-level atomic ensemble, shows a damped Rabi oscillation and photon antibunching. Without suppressing the background of Rayleigh scattering, the upper limit of Cauchy criteria is estimated.

14.
Phys Rev Lett ; 97(11): 113602, 2006 Sep 15.
Article in English | MEDLINE | ID: mdl-17025883

ABSTRACT

We describe a generator of narrow-band paired photons. A single retroreflected Ti:sapphire laser is used to cool, render transparent, and parametrically pump a cloud of (87)Rb atoms. We attain a paired-photon generation rate into opposing fibers of 600 counts/s with an intensity correlation function that has a width of 5 ns, and violates the Cauchy-Schwartz criteria by a factor of 2000.

15.
Opt Lett ; 31(19): 2836-8, 2006 Oct 01.
Article in English | MEDLINE | ID: mdl-16969394

ABSTRACT

We report the extension of the technique of molecular modulation to a deuterium-filled optical fiber. Using driving lasers at 807 and 1064 nm, each with a pulse energy of several millijoules and a 200 microm diameter fiber with a length of 22.5 cm, we generate 12 sidebands with wavelengths spanning 1.56 microm to 254 nm.

16.
Opt Lett ; 31(9): 1331-3, 2006 May 01.
Article in English | MEDLINE | ID: mdl-16642102

ABSTRACT

We demonstrate coherent control of laser-induced optical breakdown in Ar and Xe with a femtosecond time-scale pulse train. By using a genetic algorithm to set the relative phases of seven optical sidebands that span two octaves of bandwidth, we enhance or suppress the probability of breakdown, vary the onset time of the spark, and to some extent, vary the position of the spark and the timing of the laser-produced shock wave.

17.
Phys Rev Lett ; 94(18): 183601, 2005 May 13.
Article in English | MEDLINE | ID: mdl-15904367

ABSTRACT

We describe experiments and theory showing the generation of counterpropagating paired photons with coherence times of about 50 ns and waveforms that are controllable at a rudimentary level. Using cw lasers, electromagnetically induced transparency and cold 87Rb atoms we generate paired photons into opposing single-mode optical fibers at a rate of approximately 12 000 pairs per second.

18.
Phys Rev Lett ; 94(3): 033904, 2005 Jan 28.
Article in English | MEDLINE | ID: mdl-15698269

ABSTRACT

We make use of coherent control of four-wave mixing to the ultraviolet as a diagnostic and describe the generation of a periodic optical waveform where the spectrum is sufficiently broad that the envelope is approximately a single-cycle in length, and where the temporal shape of this envelope may be synthesized by varying the coefficients of a Fourier series. Specifically, using seven sidebands, we report the generation of a train of single-cycle optical pulses with a pulse width of 1.6 fs, a pulse separation of 11 fs, and a peak power of 1 MW.

19.
Phys Rev Lett ; 93(18): 183601, 2004 Oct 29.
Article in English | MEDLINE | ID: mdl-15525163

ABSTRACT

We report the first experimental demonstration of four-wave mixing using electromagnetically induced transparency in cold atoms. Backward-wave, phase-matched difference-frequency conversion is achieved at optical powers of a few nanowatts and at energies of less than a picojoule.

20.
Phys Rev Lett ; 91(23): 233602, 2003 Dec 05.
Article in English | MEDLINE | ID: mdl-14683184

ABSTRACT

We report the experimental demonstration of a new Raman technique that produces 200 sidebands, ranging in wavelength from 3 microm to 195 nm. By studying multiphoton ionization of nitric oxide (NO) molecules, we show mutual phase coherence among 15 visible sidebands covering 0.63 octaves of bandwidth.

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