Site-specific thrombus formation: advancements in photothrombosis-on-a-chip technology.

Thrombosis, characterized by blood clot formation within vessels, poses a significant medical challenge. Despite extensive research, the development of effective thrombosis therapies is hindered by substantial costs, lengthy development times, and high failure rates in medication commercialization. Conventional pre-clinical models often oversimplify cardiovascular disease, leading to a disparity between experimental results and human physiological responses. In response, we have engineered a photothrombosis-on-a-chip system. This microfluidic model integrates human endothelium, human whole blood, and blood flow dynamics and employs the photothrombotic method. It enables precise, site-specific thrombus induction through controlled laser irradiation, effectively mimicking both normal and thrombotic physiological conditions on a single chip. Additionally, the system allows for the fine-tuning of thrombus occlusion levels via laser parameter adjustments, offering a flexible thrombus model with varying degrees of obstruction. Additionally, the formation and progression of thrombosis noted on the chip closely resemble the thrombotic conditions observed in mice in previous studies. In the experiments, we perfused recalcified whole blood with Rose Bengal into an endothelialized microchannel and initiated photothrombosis using green laser irradiation. Various imaging methods verified the model's ability to precisely control thrombus formation and occlusion levels. The effectiveness of clinical drugs, including heparin and rt-PA, was assessed, confirming the chip's potential in drug screening applications. In summary, the photothrombosis-on-a-chip system significantly advances human thrombosis modeling. Its precise control over thrombus formation, flexibility in the thrombus severity levels, and capability to simulate dual physiological states on a single platform make it an invaluable tool for targeted drug testing, furthering the development of organ-on-a-chip drug screening techniques.

Deep neural network trained on gigapixel images improves lymph node metastasis detection in clinical settings.

The pathological identification of lymph node (LN) metastasis is demanding and tedious. Although convolutional neural networks (CNNs) possess considerable potential in improving the process, the ultrahigh-resolution of whole slide images hinders the development of a clinically applicable solution. We design an artificial-intelligence-assisted LN assessment workflow to facilitate the routine counting of metastatic LNs. Unlike previous patch-based approaches, our proposed method trains CNNs by using 5-gigapixel images, obviating the need for lesion-level annotations. Trained on 5907 LN images, our algorithm identifies metastatic LNs in gastric cancer with a slide-level area under the receiver operating characteristic curve (AUC) of 0.9936. Clinical experiments reveal that the workflow significantly improves the sensitivity of micrometastasis identification (81.94% to 95.83%, P < .001) and isolated tumor cells (67.95% to 96.15%, P < .001) in a significantly shorter review time (-31.5%, P < .001). Cross-site evaluation indicates that the algorithm is highly robust (AUC = 0.9829).

Umbilical cord blood plasma-derived exosomes as a novel therapy to reverse liver fibrosis.

BACKGROUND: Cirrhosis is a chronic liver disease whereby scar tissue replaces healthy liver parenchyma, leading to disruption of the liver architecture and hepatic dysfunction. Currently, there is no effective disease-modifying therapy for liver fibrosis. Recently, our group demonstrated that human umbilical cord blood (UCB) plasma possesses therapeutic effects in a rat model of acute liver failure. METHODS: In the current study, we tested whether exosomes (Exo) existed in UCB plasma and if they produced any antifibrotic benefits in a liver fibrosis model. RESULTS: Our results showed that UCB-Exo improved liver function and increased matrix metalloproteinase/tissue inhibitor of metalloproteinase degradation to reduce the degree of fibrosis. Moreover, UCB-Exo were found to suppress hepatic stellate cell (HSC) activity in vitro. These effects were associated with suppression of transforming growth factor-ß/inhibitor of DNA binding 1 signaling. CONCLUSIONS: These results further support that UCB-Exo have antifibrotic effects in mice with liver fibrosis and activated HSCs and may herald a new cell-free antifibrotic therapy.

Dual trajectories of loneliness and depression and their baseline correlates over a 14-year follow-up period in older adults: Results from a nationally representative sample in Taiwan.

AIMS: To explore the codevelopment between loneliness and depression in older adults, and to identify its potential baseline individual, family and extrafamilial correlates. BACKGROUND: The number of older adults around the world has steadily increased over the last decades. Later life is a particularly vulnerable life stage due to multiple unfavourable conditions, and mental health in this stage appears to become an inescapable issue. Previous research has found the cross-sectional association between loneliness and depression, but their codevelopment has been understudied. Therefore, exploring the codevelopment and its correlates has significant implications for prevention and healthcare professionals. DESIGN: A longitudinal follow-up study. METHODS: The study used nationally representative data over a 14-year follow-up period from the Taiwan Longitudinal Study on Ageing focused on Taiwanese aged 60 years and above (n = 4049). Group-based trajectory modelling, group-based dual-trajectory modelling and multinomial logistic regression were the primary analytical methods. RESULTS: We identified three distinct dual trajectories of loneliness and depression: longitudinal low-frequency lonely depressed (29.3%), longitudinal moderate-frequency lonely depressed (59.4%) and longitudinal high-frequency lonely depressed (11.3%). After considering several demographic and background characteristics, difficulty in physical functioning, number of physical symptoms and diseases, sleep quality and number of child deaths were found to be significantly associated. CONCLUSION: Across the three identified dual-trajectory groups, they all showed a stable loneliness frequency pattern over time; however, the moderate-frequency group and high-frequency group both had a trajectory of increasing depression. It seems that depression tends to change over time in a worsening direction, especially for those with a certain frequency of loneliness. Furthermore, differences in individual and family correlates were found across the groups. IMPLICATIONS FOR PRACTICE: Interventions focusing on the specific factors may help hinder coexisting loneliness and depression, and have implications for developing health promotion strategies and chronic disease care plans.

Whether to transfer mosaic embryos: a cytogenetic view of true mosaicism by amniocentesis.

RESEARCH QUESTION: Preimplantation genetic testing for aneuploidies has increasingly been employed for embryo selection, resulting in a recent surge in mosaic embryos. According to the cytogenetic results, which types of mosaic embryo survive early pregnancy, progress to the second trimester and finally result in a live birth? DESIGN: This study evaluated 30,587 pregnant women undergoing amniocentesis from January 2004 to March 2020 at the cytogenic centre of Kaohsiung Chang Gung Memorial Hospital. Samples from amniocentesis were cultured using the in-situ method. The types and distribution of level III chromosomal mosaicism (two or more cells with the same abnormality in two or more colonies and both culture dishes, clinically referred to as 'true mosaicism') were retrospectively reviewed. RESULTS: Among the 30,587 women, 78 cases (0.26%) of level III chromosomal mosaicism were identified. The types of chromosomal mosaicism were classified as sex chromosome mosaicism (SCM), autosomal chromosome mosaicism (ACM) and marker chromosome mosaicism (MCM), with SCM, ACM and MCM accounting for 58.97%, 32.05% and 8.97% of cases, respectively. The most common mosaic cell lines were monosomy X and trisomy 21. The most common mosaic cell line progressing to live birth was monosomy X. CONCLUSIONS: Mosaic monosomy X and trisomy 21 are the most common cell lines of true mosaicism determined by amniocentesis. Monosomy X mosaicism is the most common cell line in live births. For women considering the transfer of these types of mosaic embryo in a circumstance where euploid embryos are unavailable, clinicians should provide careful prenatal counselling, detailed ultrasonography and amniocentesis.

Lethal acute aortic dissection complicated with ischemic bowels in the third trimester of pregnancy: A case report.

OBJECTIVE: Aortic dissection is a rare but lethal disease. We demonstrate a rare case of acute complicated Stanford type A aortic dissection in the third trimester. CASE REPORT: A 41-year-old primiparous patient with chronic hypertension was brought to our emergency department at 34 weeks of gestation. She presented with acute tearing chest pain radiating to her back. Computed tomography revealed a Stanford type A aortic dissection. Primary cesarean section followed by open cardiovascular surgery was performed. However, ischemic bowels and bowel perforation occurred on the 9th and 11th postoperative days, respectively, and the patient died of septic shock on the 12th postoperative day. CONCLUSION: Aortic dissection must be taken into consideration for pregnant women with chronic hypertension who present with acute tearing chest pain and pulseless unilateral extremities. Bowel ischemia may occur in patients with complicated Stanford type A aortic dissection.

Planned conservative management of placenta increta and percreta with prophylactic transcatheter arterial embolization and leaving placenta in situ for women who desire fertility preservation.

INTRODUCTION: The objective of our study was to demonstrate planned conservative management of placenta increta and percreta in a single tertiary center. METHODS: From April 2005 to July 2019, patients with placenta increta and percreta were managed conservatively at the Kaohsiung Chang Gung Memorial Hospital in Taiwan. The severity of placenta invasion was diagnosed by magnetic resonance imaging (MRI). After delivery of the neonate, prophylactic transcatheter arterial embolization (TAE) was performed immediately. The placenta was left in situ and prophylactic antibiotics were administered during hospitalization. The patient profiles, outcomes, and complications were retrospectively reviewed. RESULTS: Based on the MRI findings, twenty-one patients with placenta increta or percreta were included. With prophylactic TAE, the mean surgical blood loss was 854.7 ± 478.2 mL. The mean natural resorption time of residual placenta was 4.69 ± 1.65 months. Regarding maternal complications, 4 patients (19%) had delayed postpartum hemorrhage (PPH), 12 patients (57.1%) developed postpartum infections, 3 patients (14.3%) progressed to sepsis, 4 patients (19%) underwent surgical evacuation, and 4 patients (19%) underwent hysterectomy. No maternal mortality was reported. Main neonatal complications were prematurity and respiratory distress. Regarding fertility, 16 (76.1%) patients had return of menstruation, and one (4.7%) had a subsequent pregnancy resulting in a live birth. DISCUSSION: Planned conservative management with prophylactic TAE and leaving placenta in situ is feasible and safe for women with placenta increta or percreta who desire fertility preservation. Delayed PPH and postpartum infection are common complications after conservative treatment.

A critical role of autophagy in regulating the mesenchymal transition of ductular cells in liver cirrhosis.

Our previous studies have shown that autophagy mediates the link between ductular reaction (DR) and liver cirrhosis. Whether the subsequent fibrogenic response is regulated by increased autophagy in DR remains unclear. Here, using both human liver specimens and a rat model of liver cirrhosis induced by 2-acetylaminofluorene (AAF) and carbon tetrachloride (CCL4), we explored the involvement of autophagy in regulating mesenchymal transition of ductular cells. Ductular cells from AAF/CCL4 livers exhibited increased autophagy compared to those of normal livers. These cells showed morphological and functional characteristics of mesenchymal cells. Blocking autophagy using bafilomycin A1 or siRNA targeting ATG7 reduced the expression of mesenchymal markers in these ductular cells from AAF/CCL4 livers, indicating a role for autophagy in regulating the mesenchymal phenotype of ductular cells. Furthermore, we show that the mesenchymal transition in DR requires the activation of transforming growth factor-ß (TGF-ß) signaling in an autophagy-dependent manner. Importantly, in cirrhotic human livers, ductular cells that are positive for LC3B also showed increased expression of TGF-ß and fibroblast-specific protein-1. Our data suggest activation of autophagy in ductular cells, and also demonstrate that it is required for the mesenchymal transition during the DR, processes that are critically involved in the pathogenesis of cirrhosis.

Therapeutic Potential of Plasma Proteins Derived from Umbilical Cord Blood for Acute Liver Failure.

There are very limited clinically viable treatment options for acute liver failure, a life-threatening condition that rapidly progresses to loss of liver function. In this study, we aim to evaluate the therapeutic potential of UCBP for acute liver failure induced in a rat model by D-galactosamine (GalN). F344 rats were randomly divided into two groups (control and UCBP-treated) after GalN injection. The therapeutic effects of UCBP were evaluated based on survival rate, H&E staining, TUNEL, PCNA staining, and in vivo BrdU labeling. Hepatocyte proliferation and the therapeutic mechanisms of UCBP were examined with BrdU and Western blot assay in vitro. The survival rate in the UCBP-treated group was found to be increased compared to the control group (85 vs 55%, P = 0.029). UCBP treatment significantly decreased apoptosis and increased cell proliferation. These effects may be secondary to specific bioactive molecules in UCBP. In vitro experiments revealed that adiponectin is one of the key biologically active components of UCBP in facilitating this result and promoting hepatocyte proliferation. Furthermore, this effect is mediated by p38/ERK mitogen-activated protein kinase (MAPK) signaling pathways. Therefore, this uncomplicated and clinically accessible approach may serve as effective bridge therapy for acute liver failure.

Src-homology protein tyrosine phosphatase-1 agonist, SC-43, reduces liver fibrosis.

This study aimed to investigate the role of src-homology protein tyrosine phosphatase-1 (SHP-1)-signal transducer and activator of transcription 3 (STAT3) pathway in liver fibrogenesis and the anti-fibrotic effect of SHP-1 agonist. The antifibrotic activity of SC-43, a sorafenib derivative with an enhanced SHP-1 activity, was evaluated in two fibrosis mouse models by carbon tetrachloride induction and bile duct ligation. Rat, human, and primary mouse hepatic stellate cells (HSCs) were used for mechanistic investigations. The results showed that SHP-1 protein primarily localized in fibrotic areas of human and mouse livers. SC-43 treatment reduced the activated HSCs and thus effectively prevented and regressed liver fibrosis in both fibrosis mouse models and improved mouse survival. In vitro studies revealed that SC-43 promoted HSC apoptosis, increased the SHP-1 activity and inhibited phospho-STAT3. The enhanced SHP-1 activity in HSCs significantly inhibited HSC proliferation, whereas SHP-1 inhibition rescued SC-43-induced HSC apoptosis. Furthermore, SC-43 interacted with the N-SH2 domain of SHP-1 to enhance the activity of SHP-1 as its antifibrotic mechanism. In conclusion, the SHP-1-STAT3 pathway is crucial in fibrogenesis. SC-43 significantly ameliorates liver fibrosis through SHP-1 upregulation. A SHP-1-targeted antifibrotic therapy may represent a druggable strategy for antifibrotic drug discovery.

Protection against acetaminophen-induced acute liver failure by omentum adipose tissue derived stem cells through the mediation of Nrf2 and cytochrome P450 expression.

BACKGROUND: Acetaminophen (APAP) overdose causes acute liver failure (ALF) in animals and humans via the rapid depletion of intracellular glutathione (GSH) and the generation of excess reactive oxygen species (ROS) that damage hepatocytes. Stem cell therapy is a potential treatment strategy for ALF. METHODS: We isolated mesenchymal stem cells (MSCs) from mice omentum adipose tissue-derived stem cells (ASCs) and transplanted them into a mouse model of APAP-induced ALF to explore their therapeutic potential. In addition, we performed in vitro co-culture studies with omentum-derived ASCs and primary isolated hepatocytes to demonstrate the hepatoprotective effect of omentum-derived ASCs on hepatocytes that were subjected to APAP-induced damage. RESULT: ASC transplantation significantly improved the survival rate of mice with ALF and attenuated the severity of APAP-induced liver damage by suppressing cytochrome P450 activity to reduce the accumulation of toxic nitrotyrosine and the upregulation of NF-E2-related factor 2 (Nrf2) expression, resulting in an increase in the subsequent antioxidant activity. These effects protected the hepatocytes from APAP-induced damage through the suppression of downstream MAPK signal activation and inflammatory cytokine production. CONCLUSIONS: our results demonstrate that omentum-derived ASCs are an alternative source of ASCs that regulate the antioxidant response and may represent a beneficial therapeutic strategy for ALF.

Hepatocyte-Like Cells Derived From Mouse Induced Pluripotent Stem Cells Produce Functional Coagulation Factor IX in a Hemophilia B Mouse Model.

Hemophilia B (HB) is an inherited deficiency in coagulation factor IX (FIX) that leads to prolonged bleeding after injury. Although hepatocyte transplantation has been demonstrated to be an effective therapeutic strategy for HB, the quality and sources of hepatocytes still limit their application. Recently, stem cells were proposed as an alternative source of donor cells for cell-based therapy. Much research has been devoted to the properties of stem cells that can be differentiated into functional hepatocytes, thereby providing a new cell source for cell-based therapy. Induced pluripotent stem cells (iPSCs) represent a renewable source of hepatocytes for cell-based therapy; these cells exhibit pluripotency and differentiation ability and can be derived from somatic cells. These iPSCs are highly similar to embryonic stem cells (ESCs). We hypothesized that hepatocyte-like cells derived from iPSCs would have therapeutic efficiency in a mouse model of HB. To test this hypothesis, we differentiated iPSCs toward hepatocytes by stepwise protocol and then transplanted these cells into HB mice. We found that these cells shared many characteristics with hepatocytes, such as albumin synthesis, metabolic capacity, glycogen storage, and ureagenesis. Moreover, iPSC-derived hepatocyte transplantation led to increased coagulation factor IX activity, improved thrombus generation, and better hemostasis parameters, and the transferred cells were localized in the liver in recipient HB mice. In conclusion, our results clearly demonstrate that hepatocyte-like cells derived from iPSCs represent a potential cell source for cell-based therapy in the treatment of HB.

Extracting photon periodic orbits from spontaneous emission spectra in laterally confined vertically emitted cavities.

We report our observation of the signature of photon periodic orbits in the spontaneous emission spectra of large-aperture vertical-cavity surface-emitting lasers (VCSELs). The high-resolution measurement clearly demonstrates that over a thousand cavity modes with a narrow linewidth can be perfectly exhibited in the spontaneous emission spectrum just below the lasing threshold. The Fourier-transformed spectrum is analyzed to confirm that the spontaneous emission spectra of large-aperture VCSELs can be exploited to analogously investigate the energy spectra of the 2D quantum billiards.

Shikonin induces apoptosis through reactive oxygen species/extracellular signal-regulated kinase pathway in osteosarcoma cells.

Shikonin, a major ingredient in the Chinese traditional herb Lithospermum erythrorhixon, exhibits multiple biological functions including antimicrobial, anti-inflammatory, and antitumor effects. In this study, we delineated the molecular mechanisms of shikonin in the apoptosis of 143B osteosarcoma cells. Shikonin reduced the cell viability of 143B cells in a dose- and time-dependent manner. The IC(50) at 24 h and 48 h for 143B cells was 4.55 and 2.01microM, respectively. A significantly elicited hypodiploid cell population was found in cells treated with 2, 4, and 8microM shikonin for 24 h. Moreover, treatment with shikonin induced reactive oxygen species (ROS) generation, increased extracellular signal-regulated kinase (ERK) phosphorylation, decreased B-cell lymphoma-2 (Bcl2) expression, and was accompanied by poly(ADP-ribose) polymerase (PARP) cleavage. Pretreatment with the antioxidant agent N-acetyl cysteine (NAC) not only reversed shikonin-induced ROS generation but also significantly attenuated the cytotoxic effects of shikonin in 143B cells. Furthermore, NAC attenuated shikonin-induced ERK phosphorylation. Taken together, our results reveal that shikonin increased ROS generation and ERK activation, and reduced Bcl2, which consequently caused the cells to undergo apoptosis. Therefore, shikonin may be a promising chemotherapeutic agent for osteosarcoma treatment.

Genetic modification of donor hepatocytes improves therapeutic efficacy for hemophilia B in mice.

Hepatocyte transplantation (Tx) holds promise for curing genetic liver diseases. However, a limited number of donor hepatocytes can be transplanted into the host liver. Recipient preconditioning and donor cell engineering are under investigation to improve cell engraftment. In theory, genetically engineered cells secreting therapeutic proteins with superior function could compensate for poor engraftment efficiency. We have generated a bioengineered human coagulation factor IX (FIX) with augmented specific activity (named FIX-Triple). The aim of this study was to evaluate therapeutic efficacy of cell therapy using hemophilia B (HB) as a disease model by transplanting FIX-Triple-secreting hepatocytes. The donor hepatocytes were isolated from FIX-Triple knock-in (KI) or FIX-WT (wild-type) KI mice and transplanted intrasplenically into FIX knock-out (KO) mice. FIX-Triple KI recipients exhibited fourfold higher plasma FIX clotting activity than FIX-WT KI recipients. By repeated Txs, the clotting activity of FIX-Triple KI recipients even increased to more than 10% of normal mouse plasma. The engraftment and FIX production efficiencies of transplanted cells were equivalent between the FIX-WT KI and FIX-Triple KI donors. A hemostatic function assay showed that FIX-Triple KI recipients with repeated Txs had more enhanced clot kinetics and a greater maximum rate of thrombus generation than those with a single Tx. Moreover, FIX inhibitors in these recipients rarely developed. In conclusion, hepatocyte Tx with genetically engineered donor cells is an effective therapeutic strategy for HB.

Chlorophyll a, an active anti-proliferative compound of Ludwigia octovalvis, activates the CD95 (APO-1/CD95) system and AMPK pathway in 3T3-L1 cells.

Ludwigia octovalvis is an aquatic plant widely distributed in Taiwan. It is traditionally used as a diuretic and is consumed as health drink. In this study, we evaluated the anti-proliferative activity of extracts and active constituent (chlorophyll a; CHL-a) of L. octovalvis in 3T3-L1 adipocytes; its mode of action on apoptosis was also investigated. Results showed that, among the different extracts and fractions, the ethylacetate layer (EAL) possessed the most potent anti-proliferative activity. Activity guided fractionation of the EAL obtained the bioactive constituent CHL-a (IC50: 24.10+/-0.83 nM). At concentrations 5-30 nM, CHL-a exhibited a dose-dependent accumulation of the Sub-G1 peak and caused cell cycle arrest at the G0/G1 phase. At 30 nM, it significantly reduced the cell viability, induced the appearance of DNA fragments, and enhanced the activation of caspase-3. Western blot data revealed that CHL-a decreased the level of Bcl-2, and increased the expression of CD95 (APO-1/CD95) and Bax. Furthermore, CHL-a up-regulated the AMPK and p-AMPK levels, and down-regulated the expression of PPAR-gamma. These results conclude that CHL-a possesses potent anti-proliferative activity, and its apoptotic effects on 3T3-L1 adipocytes are mediated through the activation of CD95 (APO-1/CD95) system and the AMPK signaling pathway.

Generation of disinfection by-products (DBPs) at two advanced water treatment plants.

A sampling program was conducted to investigate the formation of disinfection by-products (DBPs) and dissolved organic carbon (DOC) at two advanced water treatment plants in Kaohsiung City, Taiwan. The results in this study can be used as a reference for the operational control of water treatment plants and the setting of regulations in Taiwan. Samples of drinking water were collected from two advanced water treatment plants from June 2007 to April 2008. Changes in the concentration of dissolved organic carbon, the trihalomethane formation potential, and the haloacetic acids formation potential were measured in raw water samples. Variations in the concentrations of trihalomethanes (THMs) and haloacetic acids (HAA(5)) in finished drinking water were evaluated. The major species of HAA(5) were in the order of dichloroacetic acid and trichloroacetic acid and the THM was of trichloromethane. DOC was strongly related to DBPs in raw water. In this investigation, the removal efficiency of DBPs in Plant A (ultrafiltration/reverse osmosis system) exceeded that in Plant B (ozonation/biological activated carbon system). Both advanced water treatment plants greatly improved the quality of drinking water.