• Asian Pacific Journal of Cancer Prevention
• /
• 제16권12호
• /
• pp.4881-4883
• /
• 2015

A population-based relationship between low vitamin D status and increased cancer risk is now generally accepted. However there were only few studies reported on prognostic impact. To determine the effect of low vitamin D on progression of breast cancer, we conducted a cross-sectional analysis of vitamin D levels and clinico-pathological characteristics in 200 cases of breast cancer diagnosed during 2011-2012 at the National Cancer Institute of Thailand. Vitamin D levels were measured by high-performance liquid chromatography (HPLC). Clinical and pathological data were accessed to examine prognostic effects of vitamin D. We found that the mean vitamin D level was $23.0{\pm}6.61ng/ml$. High vitamin D levels (${\geq}32ng/ml$) were detected in 7% of patients, low levels (<32 ng/ml) in 93% Mean vitamin D levels for stages 1-4 were $26.1{\pm}6.35$, $22.3{\pm}6.34$, $22.2{\pm}6.46$ and $21.3{\pm}5.42ng/ml$ respectively (P=0.016) and 24.1 and 21.3 ng/ml for lymph node negative and positive cases (P=0.006). Low vitamin D level (<32 ng/ml) was significantly found in majority of cases with advanced stage of the disease (P=0.036), positive node involvement (P=0.030) and large tumors (P=0.038). Our findings suggest that low and decreased level of vitamin D might correlate with progression and metastasis of breast cancer.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권14호
• /
• pp.5913-5916
• /
• 2015

Gestational trophoblastic neoplasia (GTN) is the malignant form of gestational trophoblastic disease. In non-metastatic GTN, the outcomes of treatment are impressive with methotrexate (MTX) or actinomycin D. We retrospectively reviewed the outcomes of non-metastatic GTN treated at our center from January, 1999 to December, 2013. One hundred and nine patients were recruited to the study. The median age was 33.1 years and over 90% were referral cases. Abnormal vaginal symptoms developed in 37.6% while 56.4% were asymptomatic. The most common antecedent pregnancy was a complete mole (92.7%) with the median interval time from antecedent pregnancy to GTN development being 2.0 months. The median pretreatment B-hCG was 5,624 mIu/ml. The most common first line treatment was methotrexate (MTX) and folinic acid (91.7%) followed by weekly MTX (4.6%), etoposide+ MTX+actinomycin D (EMA) (2.8%), and actinomycin D (0.9%), with the median number of cycles at 5.0. The positive response to first line chemotherapy was 73.8%. The patients were given subsequent chemotherapeutic regimens after resistance to the first line therapy and showed a final remission rate of 89.9%.The significant factor that was frequently found in patients who were non-responders to the first line treatment was a hysterectomy procedure. Two patients developed lung metastasis and brain metastasis at one and four years after the first treatment, respectively. In conclusion, the outcomes of non-metastatic GTN were excellent. However, the patients need long term follow up due to the possibility of developing multiple organ metastases.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권4호
• /
• pp.1609-1613
• /
• 2015

Purpose: To determine the rate of lymph node metastasis, oncologic and pregnancy outcomes in apparent early-stage malignant ovarian germ cell tumor (MOGCT). Materials and Methods: Medical records of apparent early-stage MOGCT patients undergoing primary surgical treatment at Siriraj Hospital, Bangkok, Thailand, between January 2006 and December 2013, were retrospectively reviewed. Results: Thirty-eight patients had apparent stage I-II MOGCT. The mean age was $22.1{\pm}7.7years$ (median, 20.8 years; range, 7.7-35.6 years). The mean tumor size was $17.8{\pm}6.5cm$ with a median of 20 (range 4-30) cm. Three most common histopathologies were dysgerminoma (12 patients, 31.6%), immature teratoma (12 patients, 31.6%), and endodermal sinus tumor (6 patients, 15.8%). Twenty-seven of 38 patients underwent lymphadenectomy; 13 patients (48.2%) were stage IA and 8 patients (29.6%) were stage IC. The rate of retroperitoneal nodes metastasis was 7.4% (2/27 patients). At 26.1 months of median follow-up time (range 1.9-88.5 months), 9 patients retained fertility functions, with uneventful pregnancies in 3 of these. Only one patient (2.6%) had progression of disease at 4.9 months after surgery. The 5-year survival rate was 97.4%. Conclusion: As the rate of pelvic or para-aortic node metastasis in MOGCT is considerable, lymphadenectomy should be incorporated in surgical staging procedures.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권3호
• /
• pp.1289-1293
• /
• 2015

Background: Anal intraepithelial lesions (AIL) are likely to represent a precursor for anal cancer. Women infected with human immunodeficiency virus (HIV) may be at higher risk of anal cancer but a screening program for AIL still is not routinely recommended. We here studied the relationship of dysplastic cells from cervical and anal cytology in HIV-infected women. Materials and Methods: This prospective study was conducted in Prapokklao Hospital, Thailand during 2013-2014. Five hundred and ninety nine HIV-infected women were recruited. Participants who had cytological reports of equally or over "abnormal squamous/glandular cells of undetermined significance" (ASC-US) were classified as abnormal cervical or anal cytology. Descriptive statistics and logistic regression analysis were used to evaluate correlations between groups. Results: HIV-infected women with abnormal cervical cytology had 3.8 times more risk (adjusted odd ratio 3.846, 95% confidence interval 1.247-11.862, p-value. 019) for abnormal anal cytology. The major problem of the anal Pap test in this study was the inadequacy of the collected specimens for evaluation (34.4%, 206/599). Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of cervical and anal Pap tests were 93.9/12.0, 87.3/96.9, 39.7/21.4, 99.4/94.1 and 88.1/91.4 percent, respectively. Conclusions: Abnormal cervical cytology in HIV-infected women indicates elevated risk for abnormal anal cytology. The sensitivity of the anal Pap test for detection of AIL 2/3 in HIV-infected women was quite low while specificity was excellent. Inadequacy of specimen collection for evaluation was a major limitation. Improvement of sample collection is recommended for future investigations.

• Parasites, Hosts and Diseases
• /
• 제53권3호
• /
• pp.265-270
• /
• 2015

Hemoglobinopathy and malaria are commonly found worldwide particularly in malaria endemic areas. Thalassemia, the alteration of globin chain synthesis, has been reported to confer resistance against malaria. The prevalence of thalassemia was investigated in 101 malaria patients with Plasmodium falciparum and Plasmodium vivax along the Thai-Myanmar border to examine protective effect of thalassemia against severe malaria. Hemoglobin typing was performed using low pressure liquid chromatography (LPLC) and ${\alpha}$-thalassemia was confirmed by multiplex PCR. Five types of thalassemia were observed in malaria patients. The 2 major types of thalassemia were Hb E (18.8%) and ${\alpha}$-thalassemia-2 (11.9%). There was no association between thalassemia hemoglobinopathy and malaria parasitemia, an indicator of malaria disease severity. Thalassemia had no significant association with P. vivax infection, but the parasitemia in patients with coexistence of P. vivax and thalassemia was about 2-3 times lower than those with coexistence of P. falciparum and thalassemia and malaria without thalassemia. Furthermore, the parasitemia of P. vivax in patients with coexistence of Hb E showed lower value than coexistence with other types of thalassemia and malaria without coexistence. Parasitemia, hemoglobin, and hematocrit values in patients with coexistence of thalassemia other than Hb E were significantly lower than those without coexistence of thalassemia. Furthermore, parasitemia with coexistence of Hb E were 2 times lower than those with coexistence of thalassemia other than Hb E. In conclusion, the results may, at least in part, support the protective effect of thalassemia on the development of hyperparasitemia and severe anemia in malaria patients.

• 천문학논총
• /
• 제30권2호
• /
• pp.175-178
• /
• 2015

Due to the lack of an accretion disk in a polar (magnetic cataclysmic variable, MCV), the material transferred from the secondary is directly accreted onto the white dwarf, forming an accretion stream and a hot spot on the white-dwarf component. During the eclipses, different light components can be isolated. Therefore, the monitoring of eclipsing polars could provide valuable information on several modern astrophysical problems, e.g., CVs as planetary hosting stars, mass transfer and mass accretion in CVs, and the magnetic activity of the most rapidly rotating cool dwarfs. In the past five years, we have monitored about 10 eclipsing polars (e.g., DP Leo and HU Aqr) using several 2-m class telescopes and about 100 eclipse profiles were obtained. In this paper, we will introduce the progress of our research group at YNOs. The first direct evidence of variable mass transfer in a CV is obtained and we show that it is the dark-spot activity that causes the mass transfer in CVs. Magnetic activity cycles of the cool secondary were detected and we show that the variable mass transfer is not caused by magnetic activity cycles. These results will shed light on the structure and evolution of close binary stars (e.g., CVs and Algols).

• 천문학논총
• /
• 제30권2호
• /
• pp.201-204
• /
• 2015

The common-envelope process is a complicated phase in binary evolution. A lot of effort has been dedicated to study the common-envelope stage, but many questions related to this process are yet to be answered. If one member of the binary survives the common-envelope phase, the binary will emerge as a white dwarf accompanied by a low-mass main sequence star in close orbit, often referred as a post common-envelope binary (PCEB). SDSS J0745+2631 is among the list of newly found PCEBs from the Sloan Digital Sky Survey (SDSS). This star is proposed to be a strong eclipsing system candidate due to the ellipsoidal modulation in its light curve. In this work, we aim to confirm the eclipsing nature of SDSS J0745+2631 and to determine the stellar and orbital parameters using the software Binary Maker 3.0 (BM3.0). We detected the primary eclipse in the light curve of SDSS J0745+2631 in our follow-up observation from January 2014 using the ULTRASPEC instrument at the Thai National Observatory. The data obtained on 7th and 8th January 2014 in g filter show an evident drop in brightness during the eclipse of the white dwarf, but this eclipse is less prominent in the data taken on the next night using a clear filter. According to our preliminary model, we find that SDSS J0745+2631 hosts a rather hot white dwarf with an effective temperature of 11500K. The companion star is a red dwarf star with a temperature of 3800K and radius of 0.3100 $R_{\odot}$. The red dwarf star almost fills its Roche lobe, causing a large ellipsoidal modulation. The mass ratio of the binary given by the Binary Maker 3.0 (BM3.0) model is M2/M1 = 0.33.

• 천문학논총
• /
• 제30권2호
• /
• pp.397-399
• /
• 2015

Recently, cosmic voids have been recognized as a powerful cosmological probe. A number of studies have focused on the effects of the gravitational lensing by voids on the temperature (and in some cases polarization) anisotropy of the Cosmic Microwave Background (CMB) background at relatively large to medium scales, l ~ 1000. Many of these studies attempt to explain the unusually large cold spot in CMB temperature maps and dynamical evidence of dark energy via detections of late-time integrated Sachs Wolfe (ISW) effect. Here, the effects of lensing by voids on the CMB temperature anisotropy at small scales, up to l = 3000, will be investigated. This work is carried out in the light of the benefits of adding large catalogues of cosmic voids, to be identified by future large galaxy surveys such as EUCLID and LSST, to the analysis of CMB data such as those from Planck mission. Our numerical simulation utilizes two methods, namely, the small-de ectionangle approximation and full ray-tracing analysis. Using the fitted void density profiles and radius (RV ) distribution available in the literature from N-body simulations, we simulated the secondary temperature anisotropy (lensing) of CMB photons induced by voids along a line of sight from redshift 0 to 2. Each line of sight contains approximately 1000 voids of effective radius $RV_{,eff}=35h^{-1}Mpc$ with randomly distributed radial and projected positions. Both methods are used to generate temperature maps. The two methods will be compared for their accuracy and effciency in the implementation of theoretical modeling.

• 천문학논총
• /
• 제30권2호
• /
• pp.219-221
• /
• 2015

We present our recent observations of SDSS J102102.25+174439.9, a new eclipsing white dwarf - main sequence WDMS binary with an orbital period of 0.14 days. This system belongs to the post common-envelope binary group as shown by the spectrum from the Sloan Digital Sky Survey. We obtained our data using the ULTRASPEC instrument installed on the 2.4-m telescope at the Thai National Observatory (TNO). Our multi-band observations reveal an unusual and persistent drop in brightness after the primary eclipse. These dips, which appear to show variations in amplitude, also have a complex shape that changes within days. Dips in WDMS systems have been observed on only one other occasion, in the light curve of QS Vir prior to the eclipse of the white dwarf. The dips in SDSS J1021+1744 are unique because they are present at different wavelengths and they occur approximately at similar phases. Hosting a DA white dwarf and an M4 companion star, this system is known to be the only WDMS to show these kind of dips in its light curve. It is possible that these dips are caused by ejected materials from an active companion star, such as in QS Vir. The light curve in the g' filter exhibits deep and narrow features, implying that the material which passes in front of the white dwarf in SDSS J1021 must be dense and small in size. Furthermore, we try to constrain the stellar and orbital parameters of SDSS J1021+1744 using the Binary Maker 3 software. We use g' and r' data for our light curve analysis to have a better approximation for the red dwarf star.

• 천문학논총
• /
• 제30권2호
• /
• pp.217-218
• /
• 2015

In this work, we present the result of our follow-up observations of SDSS J092741.73+332959.1 and SDSS J130733.49+215636.7 using the 2.35 m Thai National Telescope and ULTRASPEC instrument. Both systems are listed among the recently found white dwarf main sequence binaries from the Sloan Digital Sky Survey. SDSS J092741.73+332959.1 is a new PCEB with a period of 2.3 days, the longest orbital period known to date for white dwarf binaries. SDSS J130733.49+215636.7 is confirmed to be an eclipsing system with a period of 0.21 days from the Catalina Survey's light curve, however the parameters for the white dwarf are still uncertain. Our goal is to determine precise parameters for both systems using the Binary Maker 3 software. The observation for SDSS J0927+3329 was done on 9 January 2014 in the SDSS r' filter while the data for SDSS J1307+2156 were taken in the z' filter on 27 April 2014. Our models show that the red dwarf companions in both systems are well constrained inside their Roche Lobes. We find that the binary M2/M1 ratio in SDSS J0927+3329 is close to 0.5, with white dwarf and M-dwarf temperatures of 12000 K and 3300 K, respectively. Our preliminary result for SDSS J1307+2156 show that this system has an extreme mass ratio of 0.3. The white dwarf in this system has a temperature of 7500 K and the companion star has an effective temperature of 3150 K.