醫學與健康科學

本研究利用 Verapamil 誘導斑馬魚胚胎心衰竭模式，並探討 Dapagliflozin 對斑馬魚胚胎表皮離子細胞的調控機制，以加深對 SGLT2 inhibitors 機制的了解。受精後第四天的斑馬魚在暴露於Verapamil 24小時後，除了抑制卵黃囊吸收以及造成心包膜水腫以外，對心臟整體功能(HR, EDV,ESV, SV, EF, CO)具負面影響。以粒線體染劑標記離子細胞，發現Verapamil使其密度上升，使用掃描式電子顯微鏡觀察，則可看到離子細胞頂端開口有明顯的萎縮，影響到正常功能。以抗體標記染色的方式檢測不同離子細胞亞型，顯示 Dapagliflozin 使富含 Na⁺-K⁺ ATPase 的 HR 細胞和富含 H⁺-ATPase 的 NaR 細胞密度上升。同時，心臟功能診斷標誌物的 mRNA 水平(naap, nppb,gata4, vmhc)暴露於Verapamil後上升，促進離子細胞代償性上調。

研究旨在檢測牛樟芝菌絲萃取物4-Acetylantroquinonol B和Antrodin C對口腔癌幹細胞的影響。過去研究發現細胞膜蛋白CD44的表現與癌幹性有密切關係，因此本實驗著重於追蹤CD44的表現情況。透過3D懸浮培養獲得腫瘤球來擴增癌幹細胞群並用流式細胞儀分析。隨著兩種牛樟芝萃取物的濃度增加，CD44表現量下降，顯示此二化合物可能可以抑制其表現。實驗顯示牛樟芝萃取物不僅抑制癌幹細胞的存活率，且在低濃度下顯著抑制成球效率，還能促進癌幹細胞的凋亡。研究結果說明牛樟芝萃取物對癌幹細胞有影響，而這個發現可能可以提供潛在的治療靶點，有益未來口腔癌治療發展。

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.

In photodynamic therapy (PDT), reactive oxygen species are generated within the cytoplasm to destroy cancer cells selectively. Using porphyrinic structures (PS) as photosensitizers holds promise for targeting cancer cells. However, direct incorporation of the porphyrins into cancer cells remains elusive. Hence, Dr. Martina Vermathen’s research introduced specific membranous phospholipid nanocarriers for topical porphyrin applications. However, since a sufficiently high enough concentration of PS in cancer cells has not yet been achieved, this study aimed to improve skin uptake of the nanocarriers. Two approaches were examined: (1) comparing polar and nonpolar porphyrins and (2) assessing the effect of a penetration enhancer, DMSO, through a neat and diluted application. The polarity of the porphyrins was first quantified with a log P test. The nanocarriers were assembled by incorporating two different PS compounds, either the mono- or tetra-4-carboxy substituted phenyl porphyrin. They were then characterized by 1D and 2D-NMR analysis. The porphyrin permeation was tested by Franz diffusion tests on pig ear skin. For the second approach, DMSO was added in the Franz diffusion test, either directly applied on the skin (“neat“) or diluted in the nanocarriers (“diluted”). The log P test for the mono- and the tetra-carboxyphenyl porphyrin resulted in values of 4.5 and -1.1, respectively. The more polar tetra-carboxyphenyl porphyrin exhibited 2.8 times better skin uptake compared to the mono-carboxyphenyl porphyrin. The neat DMSO application increased uptake by a factor of 5.5. The diluted DMSO application worsened skin uptake slightly. Analytical techniques revealed differences in porphyrin encapsulation: The mono-carboxyphenyl porphyrins were encapsulated in the centre, whereas tetra-carboxyphenyl porphyrins were localised around the nanocarriers. Results indicated potential instability of the nanocarriers. The more polar tetra-substituted porphyrins showed superior skin diffusion than the mono-substituted derivative. The neat DMSO application facilitated enhanced skin uptake by inducing membrane destabilization and pore formation but may have limited applicability. Further research is suggested to explore porphyrinic PS with alternative polar substitution patterns and tailored penetration enhancers for lipid-based delivery systems. Overall, the study underscores the importance of molecular properties of the PS system and demonstrates the potential of penetration enhancers in optimizing PDT for skin cancer treatment.

Certain specially structured ceramics, which can be used as biomaterials to replace bone, have recently started being utilized in the medical field. The aim of this study is to produce high-bioactivity silica from corn cob waste, a widely available organic material in nature, and combine it with calcium oxide (CaO) obtained by grinding organic mussel shell waste with high bioactivity. This combination is intended to synthesize dicalcium silicate (2CaO.SiO₂) to develop an alternative tissue scaffold with high bioactivity, capable of replacing bone, for existing titanium alloys. The goal is to incorporate this scaffold into PEEK (polyether ether ketone), a novel tissue scaffold material, at varying percentages to create a next-generation innovative bone substitute material. An additional objective is to demonstrate through biocompatibility tests that the produced ceramic-polymer biocomposite exhibits antibacterial activity against Staphylococcus aureus.

Burns are a major global health concern especially in developing countries like 印尼, where southeast asian women experience the highest burn incidents globally. Burns can cause severe physical and psychological impacts, with treatments that are critical to reduce complications. This study focuses on the development of organic, cost-effective burn gels using flavonoid compounds which are Quercetin and Myrecetin which are taken from pilea melastomoides leaves, a wild 印尼n plant and carrot (Daucus Carota). These skin extracts aim to accelerate wound healing, minimize pain and prevent infection. The gel formation involves extracting active compounds using 96% ethanol as it has been effectively used for extracting a wide range of bioactive compounds to preserve their quality by preventing microbial contamination, and ensures a high yield of active ingredients suitable for topical applications. Then it goes through a process of Phytochemical screening to confirm the presence of flavonoids by using the Shinoda test. The formulation process included dissolving the HPC-m (Hydroxypropyl Cellulose) as a gelling agent, then adding plant extracts (pilea melastomoides leaves and carrot), as well as combining other ingredients such as propylene glycol, sodium benzoate, sodium metabisulfite, and disodium EDTA. The gel was stirred thoroughly to ensure uniformity and left at room temperature for 48 hours to attain the required consistency. The gel that was formatted went under various quality assessments, first being organoleptic testing. This test is used to evaluate its physical characteristics which includes color aroma, and consistency which confirms a stable dark green appearance and a natural strong scent from the plant extracts. The homogeneity test is used to verify the uniformity distribution of active compounds across the gel, to ensure a consistent efficacy. The pH test showed the gel’s acidity level which remained the safe range for skin application. Additionally, the spreading ability test demonstrated the gel’s excellent application properties, with consistent results across trials. Subsequently, the in silico analysis was conducted to predict the behaviour of specific flavonoid compounds used which is the myricetin and quercetin, highlighting their potential anti-inflammatory and antimicrobial activities. Further bacterial contamination tests confirmed the gel’s antimicrobial efficacy, reducing the risk of infection in wounds. This study demonstrates that the gel, formulated with pilea melastomoides leaves and carrot skin extracts, effectively utilizes flavonoids and other phytochemicals to reduce inflammation, promote tissue regeneration and retain moisture, which fosters an optimal condition for wound healing. This organic and sustainable burn treatment utilizes locally sourced ingredients, providing a natural solution that speeds up recovery, reduces pain and prevents infections. The results highlight its significant potential for wider healthcare use, especially in resource-limited environments.

癌症幹細胞被認為是癌症會復發的主因，本研究著眼於探討新合成吲哚類化合物對癌細胞及癌幹細胞的效應與可能的作用機制。透過體外細胞實驗，我們使用不同神經膠質母細胞瘤細胞株，評估化合物對細胞增殖、存活和凋亡的作用。接著以類癌幹細胞球篩檢評估化合物對癌症幹細胞的影響。研究結果顯示，該化合物對神經膠質母細胞瘤及其癌幹細胞皆有一定程度的抑制效果。 同時，透過分子生物學技術，研究化合物的分子作用機制，結果顯示化合物能對細胞生長和凋亡的路徑產生影響。研究結果有望提供對候選抗癌藥物在細胞水平的效能、選擇性以及對癌幹細胞的特異性反應的深入理解。 期望本研究成果可為癌症治療藥物的開發提供重要參考，並促使對癌症治療新方法的探索。這將有助於確定更具潛力的藥物候選者，為癌症治療領域帶來更具前瞻性的解決方案。

肝細胞癌 (HCC) 為全球導致高死亡率的癌症之一，第一線標靶治療藥物 Sorafenib 雖能延長患者存活期，但其療效有限且伴隨嚴重副作用。在癌症中，中心體異常所導致的染色體變異是腫瘤發展的關鍵因素，而動力蛋白已知參與中心體裝配，且前人研究結果表明動力蛋白與肺癌、 HCC 等多種癌症有關連 。故本研究先透過基因表現資料庫分析，發現 HCC患者中的動力蛋白重鍊基因表現量大致顯著高於一般，後以 Ciliobrevin D 抑制三種 HCC 細胞株 Hep3B、HepG2、Huh-7 中的動力蛋白，並藉細胞存活率分析、遷移試驗與西方墨點法，探討抑制動力蛋白與 HCC 的關聯。據實驗結果，抑制動力蛋白後， Huh-7 的遷移速率減緩， 蛋白質表現量亦隨抑制劑濃度升高而降低。這表示抑制動力蛋白具有抑制肝癌細胞轉移的潛力，期未來能成為肝癌新的治療靶點。