Technological University Myeik

This study investigated the reproductive cycle of the edible oyster, Crassostrea belcheri, harvested originally from creeks near Pedaing village in the southern part of Myanmar in September 2017-October 2018 through histological analysis. Five maturity stages were detected in the C. belcheri gonads: indifferent, developing, mature, spawning, and spent. The overall sex ratio of males to females of 1:0.98 showed no statistically significant difference from the expected sex ratio of 1:1 in any month. Hermaphrodites could not be observed in 250 oysters. Moreover, the quantitative monthly gonad index values varied from 1.5 in November and June to 2.75 in March. Histological analysis of C. belcheri revealed that mature male and female gonads were detected in almost all months, except in November-December 2017 and June 2018. Spawning occurred throughout the study period, except in January-March 2018, peaking at the beginning and end of the dry season in October-November and April-May, respectively.

Avian malaria and related haemosporidians (genera Haemoproteus, Plasmodium and Leucocytozoon) infect most clades of bird. Although these parasites are present in almost all continents, they have been irregularly studied across different geographical regions. Despite the high bird diversity in Asia, the diversity of avian haemosporidians in this region is largely unknown. Moreover, anthropogenic changes to habitats in tropical regions may have a profound impact on the overall composition of haemosporidian communities. Here we analyzed the diversity and host association of bird haemosporidians from areas with different degrees of anthropogenic disturbance in Myanmar, revealing an unexplored diversity of these parasites (27% of newly-discovered haemosporidian lineages, and 64% of new records of host–parasite assemblages) in these tropical environments. This newly discovered diversity will be valuable for detecting host range and transmission areas of haemosporidian parasites. We also found slightly higher haemosporidian prevalence and diversity in birds from paddy fields than in individuals from urban areas and hills, thus implying that human alteration of natural environments may affect the dynamics of vector-borne diseases. These outcomes provide valuable insights for biodiversity conservation management in threatened tropical ecosystems.

Diversity and abundance of copepods occurring in Taninthayi coastal waters were studied and analyzed from the samples collected by R/V DR. FRIDTJOF NANSEN during the Myanmar ecosystem survey 2018. Seventy-nine copepods species belonging to calanoids (51 species), cyclopoids (21 species), and harpacticoids (7 species) were identified in the copepods community of Taninthayi coastal waters. Copepods species number and density were high at the nearshore stations (Sts 799, 842, 788) and low at the offshore stations (Sts 846, 802, 823). The resulted diversity index values of copepods were varied from 2.61 to 3.78 in species diversity index (H'), from 0.89 to 0.97 in the evenness index (E'), and from 2.51 to 7.50 in species richness index (D'). According to the correlation matrix, the abundance of copepods was positively correlated with temperature, chlorophyll a and fluorescence, and negatively correlated with salinity and oxygen.

Background:Breast cancer is the most common cancer in Myanmar women. Revealing the hormonal receptor status, human epidermal growth factor receptor 2 (HER2) and Ki-67 expression is useful for estimating patient prognosis as well as determination of treatment strategy. However, immunohistochemical features and classification of molecular subtypes in breast cancers from Myanmar remain unknown.Methods:The clinicopathological features of 91 breast cancers from Myanmar women were examined. Immunohistochemistry was performed on tissue specimens with antibodies to estrogen receptor (ER), progesterone receptor (PgR), HER2, Ki-67, cytokeratin (CK)5/6 and CK14. Immunohistochemistry-based molecular subtyping was conducted.Results:Breast cancers in Myanmar women were relatively large, high grade with frequent metastatic lymph nodes. Of the 91 patients, tumors with ER positive, PgR positive, and HER2 positive were 57.1%, 37.4%, and 28.6%, respectively. The most prevalent subtype was luminal B (HER2-) (39.6%), followed by HER2 (22.0%), triple negative (TN)-basal-like (12.1%), luminal A (11.0%), TN-null (8.8%) and luminal B (HER2+) (6.6%). The mean Ki-67 expression of 91 cases was 33.9% (33.9% ± 19.2%) and the median was 28% (range; 4%-90%). The mean Ki-67 expression of luminal A, luminal B, HER2 and TN-basal-like/null was 7%, 30%, 40%, and 57%/43%, respectively. A higher Ki-67 expression significantly correlated with a higher grade, larger size and higher stage of malignancy.Conclusions:We, for the first time, investigated the histopathological features of breast cancers from Myanmar women. Myanmar breast cancers appeared to be aggressive in nature, as evidenced by high frequency of poor-prognosis subtypes with high level of Ki-67 expression.