First-Ever Study on Groundwater Discharge Zones in Tumon Bay, a Protected Marine Preserve: Novel Insights into Coral Reef Conservation
Current research shows Northern Guam to be composed of porous limestone bedrock which allow groundwater to flow out. One large discharge point has already been identified last year in north-western Guam at Ayuyu Cave. However, little is known about Tumon Bay which is known to comprise karst watersheds which should allow for SGD. This project has examined invisible groundwater discharge using a salinity meter and was able to detect two areas of concentrated freshwater discharges in Tumon Bay, with a few minor ones scattered throughout the bay. These seeps were found to have consistently lower salinity while pH varied, and hosted more marine life than other high salinity areas. Further unique coral growth in Tumon Bay’s inner lagoon was associated with these two freshwater discharges with the pH levels further segregating the types of coral species found during on-site observation. Two coral communities, staghorn Acropora and massive Porites, were found adjacent to the surveyed groundwater seeps. It’s inferred that lower wave energy in eastern Tumon Bay allows for greater plankton and other microbial growth leading to more heterotrophic coral growth, favoring Porites corals, while Western Tumon Bay has higher wave energy which leads to the growth of more autotrophic corals, such as the Acropora found in the first area surveyed. This is the first study to document the presence, location, and consequences of invisible freshwater discharges across the billion-dollar bay. This study gauges the effects of SGD on inner shore habitats, also providing a coral cover assessment across Tumon Bay using transects and quadrats. These discoveries allow for strategic coral planting, designated areas needing government protection, and show areas of appealing inner lagoon coral growth for tourism.
Eradicating Cystic Fibrosis Biofilms by a Novel Non-Toxic, Multi-Pathway Salicylate Therapy
1.1. Cystic Fibrosis Biofilms Biofilms are bacterial aggregates in a matrix of polysaccharides, proteins and nucleic acids (Donlan, 2002). They account for 80% of all chronic infections and cause over 500,000 deaths annually. Cystic fibrosis (CF) is a genetic disorder characterized by mucus accumulation in the respiratory tracts (Morrison et al., 2020). This impairs mucociliary clearance, allowing chronic colonization by bacterial biofilms, leading to fatal respiratory failure, lung scarring, and necrosis of pulmonary epithelial tissues (Martin et al., 2021). 1.2. Obstacles in Current Treatments Three major therapies are used against CF biofilms: (1) aminoglycoside antibiotics like tobramycin, (2)non-aminoglycoside antibiotics such as ciprofloxacin and vancomycin, and (3) non-antibiotic therapies including flushing, chlorination, and ultraviolet disinfection. These have two major flaws. First, they are cytotoxic; 30% of patients experience acute kidney injury after three days of intravenous aminoglycoside therapy (Joyce et al., 2017). Furthermore, non-aminoglycoside therapies can cause phospholipid buildup in lysosomes of proximal tubule epithelial cells, accounting for 10-20% of acute renal failure cases. Second, antibiotic resistance due to horizontal gene transfer and mutations has significantly reduced treatment effectiveness. Therefore, cystic fibrosis biofilms remain a critical threat with few effective treatments. 1.3. Salicylate Derivatives This project tackled this issue using an innovative non-antibiotic approach with salicylate derivatives. Salicylates, a class of benzoic acids—benzene-based carboxylic acids (Figure 1)—used in painkillers and blood thinners, were investigated for their antibiofilm potential through a 3-step process: 1. Literature review: Identified three key biofilm therapeutic targets: quorum sensing, bacterial adhesion, and cell motility. Disrupting these pathways would result in biofilm eradication. 2. Molecule Identification: Recognized key molecules in each pathway: LasR, adhesins, and flagellin. Inhibiting these molecules would disrupt the pathways. 3. Screening: Found that salicylates could inhibit the identified molecules, though they had never been tested against cystic fibrosis biofilms.
Sequentially bidirectional gastrovascular flows in highly branched digestive tracts of panocerid flatworm
Examination of the predation behavior of polyclad flatworms is extremely rare. This study collects Paraplanocera oligoglena, the most common species in Taiwan. Tank-based feeding experiments reveal that Paraplanocera oligoglena can prey on several species of gastropods, such as sea snails and sea hares. Predation behavior encompasses attack, invasion and ingestion periods. This research pioneers the use of stained clam and static image analysis to observe the highly branched digestive system of flatworms. The sequentially bidirectional flow of gastrovascular cavity is first found in polyclad flatworms by the post-stain active tracking technique. Measuring peristalsis movement in inward and outward directions and segmented movement, the contraction frequencies are roughly the same in subsequent order of given branches. Confirmation is provided that the circular membrane-like muscles within the digestive tract are the main driving force for transporting and mixing food. The food dyeing technology used in this experiment also provides the possibility of future research on food chains in the wild.
金屬多酚配位奈米載體合成與多功能腫瘤治療法開發
本研究結合奈米合成技術與生物醫學， 利用表沒食子兒茶素沒食子酸酯 (Epigallocatechin gallate, EGCG) 作為載體 調控摻雜Cu2+/Cu3+與 Fe2+/Fe3+之含量 並以π-π交互作用力附載缺氧性抗癌藥物替拉扎明 (Tirapazamine, TPZ) 成功製備出多功能金屬多酚配位奈米顆粒簡稱為EFeCuTPZ。 材料經紫外-可見光譜 (UV-vis)，、動態光散射 (DLS) 及掃描式電子顯微鏡 (SEM) 確認其粒徑大小、形貌學與穩定性。利用808 nm和671 nm雷射分析其光熱轉換效率 評估光熱療法效果，。在腫瘤微酸性環境下， EFeCuTPZ可利用高濃度之H2O2行芬頓反應 (Fenton Reaction) 產生高活性之氫氧自由基 (•OH)， 展現化學動力療法 (Chemo dynamic-therapy, CDT)，。同時， 藉由材料中的Cu²⁺與腫瘤環境中的穀胱甘肽 (Glutathione, GSH)反應減少高活性物質 (Reactive oxygen species, ROS) 的消耗 增強CDT之療效。酸性條件下 TPZ顯著釋放 有助於腫瘤治療。 另外， 細胞實驗顯示EFeCuTPZ具有高生物相容性與治療效果， 成功開發出具CDT，、CT及PTT功能之奈米複合材料 為醫學新興藥物材料提供可能性。