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1.
J Occup Environ Hyg ; 21(4): 270-286, 2024.
Article in English | MEDLINE | ID: mdl-38451632

ABSTRACT

Three-dimensional (3D) printing is an emerging and booming industry in Taiwan. Compared to traditional manufacturing, 3D printing has various advantages, such as advanced customization, additive manufacturing, reduced mold opening time, and reduced consumption of precursors. In this study, the real-time monitoring of particulate matter (PM) and total volatile organic compound (TVOC) emissions from various filaments is investigated using fused deposition modeling with material extrusion technology, a liquid-crystal display, a stereolithography apparatus based on vat photopolymerization technology, and binder jetting for occupational settings. An exposure assessment for nearby workers using the 3D printing process was performed, and improvement measures were recommended. Nine 3D printing fields were measured. The generation rate of ultrafine particles ranged from 1.19 × 1010 to 4.90 × 1012 #/min, and the geometric mean particle size ranged from 30.91 to 55.50 nm. The average concentration of ultrafine particles ranged from 2.31 × 103 to 7.36 × 104 #/cm3, and the PM2.5 and PM10 concentrations in each field ranged from 0.74 ± 0.27 to 12.46 ± 5.61 µg/m3 and from 2.39 ± 0.60 to 30.65 ± 21.26 µg/m3, respectively. The TVOC concentration ranged from 0.127 ± 0.012 to 1.567 ± 0.172 ppm. The respiratory deposition (RDUFPs) dose ranged from 2.02 × 1013 to 5.54 × 1014 nm2/day. Depending on the operating conditions, appropriate control and protective measures should be employed to protect workers' health.


Subject(s)
Air Pollution, Indoor , Volatile Organic Compounds , Humans , Taiwan , Air Pollution, Indoor/analysis , Particulate Matter/analysis , Printing, Three-Dimensional , Volatile Organic Compounds/analysis , Workplace
2.
Virology ; 589: 109920, 2024 01.
Article in English | MEDLINE | ID: mdl-37952466

ABSTRACT

Synthesis of coronavirus subgenomic mRNA (sgmRNA) is guided by the transcription regulatory sequence (TRS). sgmRNA derived from the body TRS (TRS-B) located at the 1a/1b protein gene is designated 1ab/sgmRNA. In the current study, we comprehensively identified the 1ab/sgmRNAs synthesized from TRS-Bs located at the 1a/1b protein genes of different coronavirus genera both in vitro and in vivo by RT‒PCR and sequencing. The results suggested that the degree of sequence homology between the leader TRS (TRS-L) and TRS-B may not be a decisive factor for 1ab/sgmRNA synthesis. This observation led us to revisit the coronavirus transcription mechanism and to propose that the disassociation of coronavirus polymerase from the viral genome may be a prerequisite for sgmRNA synthesis. Once the polymerase can disassociate at TRS-B, the sequence homology between TRS-L and TRS-B is important for sgmRNA synthesis. The study therefore extends our understanding of transcription mechanisms.


Subject(s)
Coronavirus , Coronavirus/genetics , Subgenomic RNA , RNA, Messenger/genetics , RNA, Viral/genetics , Transcription, Genetic , Genome, Viral
3.
Virol J ; 20(1): 290, 2023 Dec 07.
Article in English | MEDLINE | ID: mdl-38062493

ABSTRACT

During coronavirus infection, in addition to the well-known coronavirus genomes and subgenomic mRNAs, an abundance of defective viral genomes (DVGs) can also be synthesized. In this study, we aimed to examine whether DVGs can encode proteins in infected cells. Nanopore direct RNA sequencing and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis were employed. With the protein databases generated by nanopore direct RNA sequencing and the cell lysates derived from the RNA-protein pull-down assay, six DVG-encoded proteins were identified by LC-MS/MS based on the featured fusion peptides caused by recombination during DVG synthesis. The results suggest that the coronavirus DVGs have the capability to encode proteins. Consequently, future studies determining the biological function of DVG-encoded proteins may contribute to the understanding of their roles in coronavirus pathogenesis and the development of antiviral strategies.


Subject(s)
Coronavirus Infections , Coronavirus , Humans , Coronavirus/genetics , Chromatography, Liquid , Tandem Mass Spectrometry , Proteins/genetics , Genome, Viral , RNA, Viral/genetics
4.
Aging (Albany NY) ; 15(23): 14372-14383, 2023 12 14.
Article in English | MEDLINE | ID: mdl-38097341

ABSTRACT

Cisplatin has the potential to cause kidney and reproductive organ injuries, prompting the search for protective agents against cisplatin-induced toxicity. Melatonin, an antioxidant hormone, has shown promise in mitigating oxidative stress in various organs. However, its protective effects on cisplatin-induced kidney and reproductive injuries have not been extensively investigated. The aim of this study was to explore the potential protective effects of melatonin on cisplatin-induced kidney and reproductive injuries when administered in combination with gemcitabine in mice. Male C57BL/6 mice were subjected to a seven-week treatment with gemcitabine plus cisplatin, with or without melatonin intervention. The testis, epididymis, and kidney were assessed through histological analysis and measurement of blood parameters. Treatment with cisplatin led to a significant reduction in testicular weight, histological abnormalities, and alterations in reproductive hormone levels. Melatonin exhibited a slight protective effect on the testis, with higher doses of melatonin yielding better outcomes. However, melatonin did not reverse the effects of cisplatin on the epididymis. Administration of melatonin before and during treatment with cisplatin plus gemcitabine in mice demonstrated a modest protective effect on testicular injuries, while showing limited effects on epididymal injuries. Serum creatinine levels in the group treated with gemcitabine plus cisplatin treatment and high-dose melatonin approached those of the control group, indicating a protective effect on the kidney. These findings underscore the potential of melatonin as a protective agent against cisplatin-induced kidney and reproductive injuries and emphasize the need for further research to optimize its dosage and evaluate its long-term effects.


Subject(s)
Cisplatin , Melatonin , Mice , Male , Animals , Cisplatin/toxicity , Melatonin/pharmacology , Melatonin/metabolism , Gemcitabine , Mice, Inbred C57BL , Testis/metabolism , Antioxidants/pharmacology , Antioxidants/metabolism , Oxidative Stress , Kidney/pathology , Protective Agents/pharmacology
5.
Virol J ; 20(1): 267, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37968733

ABSTRACT

BACKGROUND: Coronaviruses are pathogens of humans and animals that cause widespread and costly diseases. The development of effective strategies to combat the threat of coronaviruses is therefore a top priority. The conserved coronavirus octamer motif 5'GGAAGAGC3' exists in the 3' untranslated region of all identified coronaviruses. In the current study, we aimed to examine whether targeting the coronavirus octamer motif GGAAGAGC is a promising approach to develop coronavirus vaccine. METHODS: Plaque assays were used to determine the titers of mouse hepatitis virus (MHV)-A59 octamer mutant (MHVoctm) and wild-type (wt) MHV-A59 (MHVwt). Western blotting was used for the determination of translation efficiency of MHVoctm and MHVwt. Plaque assays and RT-qPCR were employed to examine whether MHVoctm was more sensitive to interferon treatment than MHVwt. Weight loss, clinical signs, survival rate, viral RNA detection and histopathological examination were used to evaluate whether MHVoctm was a vaccine candidate against MHVwt infection in BALB/c mice. RESULTS: In this study, we showed that (i) the MHVoctm with mutation of coronavirus octamer was able to grow to high titers but attenuated in mice, (ii) with the reduced multiplicity of infection (MOI), the difference in gene expression between MHVoctm and MHVwt became more evident in cultured cells, (iii) MHVoctm was more sensitive to interferon treatment than MHVwt and (iv) mice inoculated with MHVoctm were protected from MHVwt infection. CONCLUSIONS: Based on the results obtained from cultured cells, it was suggested that the synergistic effects of octamer mutation, multiplicity of infection and immune response may be a mechanism explaining the distinct phenotypes of octamer-mutated coronavirus in cell culture and mice. In addition, targeting the conserved coronavirus octamer motif is a strategy for development of coronavirus vaccine. Since the conserved octamer exists in all coronaviruses, this strategy of targeting the conserved octamer motif can also be applied to other human and animal coronaviruses for the development of coronavirus vaccines, especially the emergence of novel coronaviruses such as SARS-CoV-2, saving time and cost for vaccine development and disease control.


Subject(s)
COVID-19 Vaccines , Murine hepatitis virus , Humans , Mice , Animals , Murine hepatitis virus/genetics , Interferons/genetics , Mutation , Cells, Cultured , SARS-CoV-2/genetics
6.
J Gen Virol ; 104(11)2023 11.
Article in English | MEDLINE | ID: mdl-37997889

ABSTRACT

How coronaviruses evolve by altering the structures of their full-length genome and defective viral genome (DVG) under dynamic selection pressures has not been studied. In this study, we aimed to experimentally identify the dynamic evolutionary patterns of the S protein sequence in the full-length genome and DVG under diverse selection pressures, including persistence, innate immunity and antiviral drugs. The evolutionary features of the S protein sequence in the full-length genome and in the DVG under diverse selection pressures are as follows: (i) the number of nucleotide (nt) mutations does not necessarily increase with the number of selection pressures; (ii) certain types of selection pressure(s) can lead to specific nt mutations; (iii) the mutated nt sequence can be reverted to the wild-type nt sequence under the certain type of selection pressure(s); (iv) the DVG can also undergo mutations and evolve independently of the full-length genome; and (v) DVG species are regulated during evolution under diverse selection pressures. The various evolutionary patterns of the S protein sequence in the full-length genome and DVG identified in this study may contribute to coronaviral fitness under diverse selection pressures.


Subject(s)
Coronavirus Infections , Coronavirus , Humans , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/chemistry , Genome, Viral , Coronavirus/genetics , Mutation
7.
Virol J ; 20(1): 232, 2023 10 12.
Article in English | MEDLINE | ID: mdl-37828527

ABSTRACT

BACKGROUND: In addition to the well-known coronavirus genomes and subgenomic mRNAs, the existence of other coronavirus RNA species, which are collectively referred to as noncanonical transcripts, has been suggested; however, their biological characteristics have not yet been experimentally validated in vitro and in vivo. METHODS: To comprehensively determine the amounts, species and structures of noncanonical transcripts for bovine coronavirus in HRT-18 cells and mouse hepatitis virus A59, a mouse coronavirus, in mouse L cells and mice, nanopore direct RNA sequencing was employed. To experimentally validate the synthesis of noncanonical transcripts under regular infection, Northern blotting was performed. Both Northern blotting and nanopore direct RNA sequencing were also applied to examine the reproducibility of noncanonical transcripts. In addition, Northern blotting was also employed to determine the regulatory features of noncanonical transcripts under different infection conditions, including different cells, multiplicities of infection (MOIs) and coronavirus strains. RESULTS: In the current study, we (i) experimentally determined that coronavirus noncanonical transcripts were abundantly synthesized, (ii) classified the noncanonical transcripts into seven populations based on their structures and potential synthesis mechanisms, (iii) showed that the species and amounts of the noncanonical transcripts were reproducible during regular infection but regulated in altered infection environments, (iv) revealed that coronaviruses may employ various mechanisms to synthesize noncanonical transcripts, and (v) found that the biological characteristics of coronavirus noncanonical transcripts were similar between in vitro and in vivo conditions. CONCLUSIONS: The biological characteristics of noncanonical coronavirus transcripts were experimentally validated for the first time. The identified features of noncanonical transcripts in terms of abundance, reproducibility and variety extend the current model for coronavirus gene expression. The capability of coronaviruses to regulate the species and amounts of noncanonical transcripts may contribute to the pathogenesis of coronaviruses during infection, posing potential challenges in disease control. Thus, the biology of noncanonical transcripts both in vitro and in vivo revealed here can provide a database for biological research, contributing to the development of antiviral strategies.


Subject(s)
Coronavirus Infections , Coronavirus , Murine hepatitis virus , Cattle , Animals , Mice , Coronavirus/genetics , Reproducibility of Results , RNA, Viral/genetics , RNA, Messenger/genetics , Murine hepatitis virus/genetics , Murine hepatitis virus/metabolism
8.
Virol J ; 20(1): 225, 2023 10 06.
Article in English | MEDLINE | ID: mdl-37803357

ABSTRACT

BACKGROUND: Defective viral genome (DVG) is a truncated version of the full-length virus genome identified in most RNA viruses during infection. The synthesis of DVGs in coronavirus has been suggested; however, the fundamental characteristics of coronavirus DVGs in gene expression and pathogenesis have not been systematically analyzed. METHODS: Nanopore direct RNA sequencing was used to investigate the characteristics of coronavirus DVGs in gene expression including reproducibility, abundance, species and genome structures for bovine coronavirus in cells, and for mouse hepatitis virus (MHV)-A59 (a mouse coronavirus) in cells and in mice. The MHV-A59 full-length genomic cDNAs (~ 31 kilobases) were in vitro constructed to experimentally validate the origin of coronavirus DVG. The synthesis of DVGs was also experimentally identified by RT-PCR followed by sequencing. In addition, the alterations of DVGs in amounts and species under different infection environments and selection pressures including the treatment of antiviral remdesivir and interferon were evaluated based on the banding patterns by RT-PCR. RESULTS: The results are as follows: (i) the structures of DVGs are with diversity, (ii) DVGs are overall synthesized with moderate (MHV-A59 in cells) to high (BCoV in cells and MHV-A59 in mice) reproducibility under regular infection with the same virus inoculum, (iii) DVGs can be synthesized from the full-length coronavirus genome, (iv) the sequences flanking the recombination point of DVGs are AU-rich and thus may contribute to the recombination events during gene expression, (v) the species and amounts of DVG are altered under different infection environments, and (vi) the biological nature of DVGs between in vitro and in vivo is similar. CONCLUSIONS: The identified biological characteristics of coronavirus DVGs in terms of abundance, reproducibility, and variety extend the current model for coronavirus gene expression. In addition, the biological features of alterations in amounts and species of coronavirus DVGs under different infection environments may assist the coronavirus to adapt to the altered environments for virus fitness and may contribute to the coronavirus pathogenesis. Consequently, the unveiled biological features may assist the community to study the gene expression mechanisms of DVGs and their roles in pathogenesis, contributing to the development of antiviral strategy and public health.


Subject(s)
Coronavirus Infections , Coronavirus , Murine hepatitis virus , Cattle , Animals , Mice , Coronavirus/genetics , Reproducibility of Results , Genome, Viral , Murine hepatitis virus/genetics , Gene Expression , Antiviral Agents , Biology , RNA, Viral/genetics
9.
Elife ; 112022 11 30.
Article in English | MEDLINE | ID: mdl-36449334

ABSTRACT

Tissue-resident macrophages are essential to protect from pathogen invasion and maintain organ homeostasis. The ability of thymic macrophages to engulf apoptotic thymocytes is well appreciated, but little is known about their ontogeny, maintenance, and diversity. Here, we characterized the surface phenotype and transcriptional profile of these cells and defined their expression signature. Thymic macrophages were most closely related to spleen red pulp macrophages and Kupffer cells and shared the expression of the transcription factor (TF) SpiC with these cells. Single-cell RNA sequencing (scRNA-Seq) showed that the macrophages in the adult thymus are composed of two populations distinguished by the expression of Timd4 and Cx3cr1. Remarkably, Timd4+ cells were located in the cortex, while Cx3cr1+ macrophages were restricted to the medulla and the cortico-medullary junction. Using shield chimeras, transplantation of embryonic thymuses, and genetic fate mapping, we found that the two populations have distinct origins. Timd4+ thymic macrophages are of embryonic origin, while Cx3cr1+ macrophages are derived from adult hematopoietic stem cells. Aging has a profound effect on the macrophages in the thymus. Timd4+ cells underwent gradual attrition, while Cx3cr1+ cells slowly accumulated with age and, in older mice, were the dominant macrophage population in the thymus. Altogether, our work defines the phenotype, origin, and diversity of thymic macrophages.


Subject(s)
Macrophages , Thymus Gland , Mice , Animals , Thymus Gland/metabolism , Thymocytes , Hematopoietic Stem Cells , Phenotype
10.
Front Immunol ; 13: 1000405, 2022.
Article in English | MEDLINE | ID: mdl-36439118

ABSTRACT

Mast cells are innate immune cells strategically positioned around blood vessels near body surfaces. Their primary weapons are bioactive amines, mast cell-specific proteases, and cytokines stored in preformed granules. Mast cells granules constituents are packaged efficiently with the help of the highly negatively charged Heparan sulfate-derivative, Heparin. Heparin is one of the most widely used drugs to treat coagulation disorders, yet, it is not found in the circulation at a steady state, casting doubt that the prevention of blood clotting is its physiological function. Early studies using Ndst2 -/- mice have shown that Heparin is essential for mast cells granules formation. However, these mice could still produce less sulfated Heparan sulfate that could potentially replace Heparin. Here, we have created and validated a novel genetic model for Heparin deficiency, specifically in connective tissue mast cells, to address the physiological role of this molecule. Using this model, we have demonstrated that Heparin is required for mast cell granules formation; without it, mast cells are reduced in the peritoneal cavity and the skin. The absence of Heparin impaired the response to passive cutaneous anaphylaxis but, surprisingly, enhanced ear swelling in an irritant dermatitis model and reduced the lesion size and bacterial burden in a Staphylococcus aureus necrotizing dermatitis model. The altered function of Heparin-deficient mast cells in the latter two models was not mediated through enhanced Histamine or TNFα release. However, the Mrgprb2 receptor was up-regulated in knock-out mast cells, potentially explaining the enhanced response of mutant mice to irritant and necrotizing dermatitis. Altogether our results expand our current understanding of the physiological role of Heparin and provide unique tools to further dissect its importance.


Subject(s)
Dermatitis , Heparin , Mice , Animals , Heparin/pharmacology , Mast Cells , Heparitin Sulfate/genetics , Connective Tissue
11.
J Chem Theory Comput ; 18(5): 3006-3016, 2022 May 10.
Article in English | MEDLINE | ID: mdl-35403426

ABSTRACT

Transition state searches are the basis for computationally characterizing reaction mechanisms, making them a pivotal tool in myriad chemical applications. Nevertheless, common search algorithms are sensitive to reaction conformations, and the conformational spaces of even medium-sized reacting systems are too complex to explore with brute force. Here, we show that it is possible to train a classifier to learn the features of reaction conformers that conduce successful transition state searches, such that optimal conformers can be down-selected before incurring the cost of a high-level transition state search. The efficacy and transferability of this approach were tested using four distinct benchmarks comprising over three hundred individual reactions. Neglecting conformer contributions led to qualitatively incorrect activation energy estimations for a broad range of reactions, whereas simple random forest classifiers reliably down-selected low-barrier reaction conformers for unseen reactions. The robust performance of these machine learning classifiers mitigates cost as a factor when implementing conformational sampling into contemporary reaction prediction workflows and opens up many avenues for further improvements as transition state data grow.


Subject(s)
Algorithms , Machine Learning , Molecular Conformation
12.
Sci Rep ; 12(1): 1555, 2022 01 28.
Article in English | MEDLINE | ID: mdl-35091636

ABSTRACT

Using deep learning models to analyze patients with intracranial tumors, to study the image segmentation and standard results by clinical depiction complications of cerebral edema after receiving radiotherapy. In this study, patients with intracranial tumors receiving computer knife (CyberKnife M6) stereotactic radiosurgery were followed using the treatment planning system (MultiPlan 5.1.3) to obtain before-treatment and four-month follow-up images of patients. The TensorFlow platform was used as the core architecture for training neural networks. Supervised learning was used to build labels for the cerebral edema dataset by using Mask region-based convolutional neural networks (R-CNN), and region growing algorithms. The three evaluation coefficients DICE, Jaccard (intersection over union, IoU), and volumetric overlap error (VOE) were used to analyze and calculate the algorithms in the image collection for cerebral edema image segmentation and the standard as described by the oncologists. When DICE and IoU indices were 1, and the VOE index was 0, the results were identical to those described by the clinician.The study found using the Mask R-CNN model in the segmentation of cerebral edema, the DICE index was 0.88, the IoU index was 0.79, and the VOE index was 2.0. The DICE, IoU, and VOE indices using region growing were 0.77, 0.64, and 3.2, respectively. Using the evaluated index, the Mask R-CNN model had the best segmentation effect. This method can be implemented in the clinical workflow in the future to achieve good complication segmentation and provide clinical evaluation and guidance suggestions.


Subject(s)
Brain Edema
13.
Int J Mol Sci ; 22(23)2021 Nov 25.
Article in English | MEDLINE | ID: mdl-34884541

ABSTRACT

Osteosarcoma is the most common type of primary malignant bone cancer, and it is associated with high rates of pulmonary metastasis. Integrin αvß3 is critical for osteosarcoma cell migratory and invasive abilities. Chemokine (C-C motif) ligand 4 (CCL4) has diverse effects on different cancer cells through its interaction with its specific receptor, C-C chemokine receptor type 5 (CCR5). Analysis of mRNA expression in human osteosarcoma tissue identified upregulated levels of CCL4, integrin αv and ß3 expression. Similarly, an analysis of records from the Gene Expression Omnibus (GEO) dataset showed that CCL4 was upregulated in human osteosarcoma tissue. Importantly, the expression of both CCL4 and integrin αvß3 correlated positively with osteosarcoma clinical stages and lung metastasis. Analysis of osteosarcoma cell lines identified that CCL4 promotes integrin αvß3 expression and cell migration by activating the focal adhesion kinase (FAK), protein kinase B (AKT), and hypoxia inducible factor 1 subunit alpha (HIF-1α) signaling pathways, which can downregulate microRNA-3927-3p expression. Pharmacological inhibition of CCR5 by maraviroc (MVC) prevented increases in integrin αvß3 expression and cell migration. This study is the first to implicate CCL4 as a potential target in the treatment of metastatic osteosarcoma.


Subject(s)
Biomarkers, Tumor/metabolism , Cell Movement , Chemokine CCL4/metabolism , Gene Expression Regulation, Neoplastic , Integrin alphaVbeta3/metabolism , MicroRNAs/genetics , Osteosarcoma/pathology , Apoptosis , Biomarkers, Tumor/genetics , Bone Neoplasms/genetics , Bone Neoplasms/metabolism , Bone Neoplasms/pathology , Cell Proliferation , Chemokine CCL4/genetics , Humans , Integrin alphaVbeta3/genetics , Osteosarcoma/genetics , Osteosarcoma/metabolism , Tumor Cells, Cultured
14.
J Hepatocell Carcinoma ; 8: 963-973, 2021.
Article in English | MEDLINE | ID: mdl-34434903

ABSTRACT

PURPOSE: Evidence is lacking concerning the benefit of the combination of sorafenib and radiotherapy to treat advanced hepatocellular carcinoma (HCC). To date, no publication has reported the outcomes of radiotherapy alone versus concurrent therapy. We aimed to compare the effectiveness of radiotherapy alone versus concurrent radiotherapy and sorafenib for locally advanced hepatocellular carcinoma. MATERIALS AND METHODS: We conducted a propensity score matching (PSM) cohort study comparing the effectiveness of the concurrent use of sorafenib and external beam radiotherapy versus radiotherapy alone in Barcelona Clinic Liver Cancer (BCLC) stage B or C, nonsurgically managed, nonmetastatic patients with HCC. Two subpopulations were matched based on baseline characteristics. Stratified analysis was also performed to assess the heterogeneous effects of the two arms. Overall survival (OS) was compared. Radiation-induced liver disease (RILD) and overt gastrointestinal (GI) bleeding events were also recorded. RESULTS: Seven hundred thirty-one BCLC stage B or C nonmetastatic HCC patients were identified from 2007 to 2017. Of these, 347 patients met the inclusion criteria (Radiotherapy alone: 269 patients; concurrent therapy: 78 patients). Propensity score matching yielded 73 patients each in the radiotherapy and concurrent groups. The median OS was 9.6 months in the radiotherapy-alone group and 9.9 months in the concurrent group (hazard ratio (HR): 1.12; 95% CI=0.78-1.62; p=0.544). Posttreatment toxicities, including radiation-induced liver disease and overt gastrointestinal bleeding, showed no significant differences between the groups. CONCLUSION: In our study, the concurrent use of sorafenib and conventional external beam radiotherapy shows no survival benefit over radiotherapy alone for locally advanced hepatocellular carcinoma.

15.
J Biol Chem ; 296: 100419, 2021.
Article in English | MEDLINE | ID: mdl-33600795

ABSTRACT

Thymus organogenesis and T cell development are coordinated by various soluble and cell-bound molecules. Heparan sulfate (HS) proteoglycans can interact with and immobilize many soluble mediators, creating fields or gradients of secreted ligands. While the role of HS in the development of many organs has been studied extensively, little is known about its function in the thymus. Here, we examined the distribution of HS in the thymus and the effect of its absence on thymus organogenesis and T cell development. We found that HS was expressed most abundantly on the thymic fibroblasts and at lower levels on endothelial, epithelial, and hematopoietic cells. To study the function of HS in the thymus, we eliminated most of HS in this organ by genetically disrupting the glycosyltransferase Ext1 that is essential for its synthesis. The absence of HS greatly reduced the size of the thymus in fetal thymic organ cultures and in vivo, in mice, and decreased the production of T cells. However, no specific blocks in T cell development were observed. Wild-type thymic fibroblasts were able to physically bind the homeostatic chemokines CCL19, CCL21, and CXCL12 ex vivo. However, this binding was abolished upon HS degradation, disrupting the CCL19/CCL21 chemokine gradients and causing impaired migration of dendritic cells in thymic slices. Thus, our results show that HS plays an essential role in the development and growth of the thymus and in regulating interstitial cell migration.


Subject(s)
Heparitin Sulfate/metabolism , Thymus Gland/growth & development , Animals , Cell Differentiation , Cell Movement , Chemokine CCL19/metabolism , Chemokine CCL21/metabolism , Heparan Sulfate Proteoglycans/metabolism , Heparitin Sulfate/biosynthesis , Mice , Mice, Inbred C57BL , N-Acetylglucosaminyltransferases , T-Lymphocytes/metabolism , Thymus Gland/drug effects
16.
Mini Rev Med Chem ; 21(1): 90-117, 2021.
Article in English | MEDLINE | ID: mdl-32600229

ABSTRACT

In the era of antimicrobial resistance, fungal pathogens are not an exception. Several strategies, including antimicrobial stewardship programs and high throughput screening of new drugs, are being implemented. Several recent studies have demonstrated the effectiveness of plant compounds with antifungal activity. In this systematic review, we examine the use of natural compounds as a possible avenue to fight fungal infections produced by Candida albicans, the most common human fungal pathogen. Electronic literature searches were conducted through PubMed/MEDLINE, Cochrane, and Science Direct limited to the 5 years. A total of 131 articles were included, with 186 plants extracts evaluated. Although the majority of the natural extracts exhibited antifungal activities against C. albicans (both in vivo and in vitro), the strongest antifungal activity was obtained from Lawsonia inermis, Pelargonium graveolens, Camellia sinensis, Mentha piperita, and Citrus latifolia. The main components with proven antifungal activities were phenolic compounds such as gallic acid, thymol, and flavonoids (especially catechin), polyphenols such as tannins, terpenoids and saponins. The incorporation of nanotechnology greatly enhances the antifungal properties of these natural compounds. Further research is needed to fully characterize the composition of all herbal extracts with antifungal activity as well as the mechanisms of action of the active compounds.


Subject(s)
Antifungal Agents/pharmacology , Candida albicans/drug effects , Plant Extracts/pharmacology , Antifungal Agents/chemistry , Antifungal Agents/isolation & purification , Camellia sinensis/chemistry , Citrus/chemistry , Humans , Lawsonia Plant/chemistry , Mentha piperita/chemistry , Microbial Sensitivity Tests , Pelargonium/chemistry , Plant Extracts/chemistry , Plant Extracts/isolation & purification
17.
Int J Mol Sci ; 21(20)2020 Oct 09.
Article in English | MEDLINE | ID: mdl-33050160

ABSTRACT

In this study, we optimized the geometry and composition of additive-manufactured pedicle screws. Metal powders of titanium-aluminum-vanadium (Ti-6Al-4V) were mixed with reactive glass-ceramic biomaterials of bioactive glass (BG) powders. To optimize the geometry of pedicle screws, we applied a novel numerical approach to proposing the optimal shape of the healing chamber to promote biological healing. We examined the geometry and composition effects of pedicle screw implants on the interfacial autologous bone attachment and bone graft incorporation through in vivo studies. The addition of an optimal amount of BG to Ti-6Al-4V leads to a lower elastic modulus of the ceramic-metal composite material, effectively reducing the stress-shielding effects. Pedicle screw implants with optimal shape design and made of the composite material of Ti-6Al-4V doped with BG fabricated through additive manufacturing exhibit greater osseointegration and a more rapid bone volume fraction during the fracture healing process 120 days after implantation, per in vivo studies.


Subject(s)
Aluminum , Bone Development , Glass , Pedicle Screws , Powders , Prostheses and Implants , Titanium , Vanadium , Animals , Biomechanical Phenomena , Bone Remodeling , Image Processing, Computer-Assisted , Osseointegration , Stress, Mechanical , Swine , Tomography, X-Ray Computed
18.
Radiat Oncol ; 15(1): 159, 2020 Jun 30.
Article in English | MEDLINE | ID: mdl-32605627

ABSTRACT

BACKGROUND: Proton radiotherapy has a dosimetric advantage over photon radiotherapy. Many retrospective studies have shown promising results with proton radiotherapy in treating hepatocellular carcinoma (HCC). However, clinical evidence demonstrating the benefit of protons over photons is still limited. We therefore compared the clinical outcomes of the two modalities using medical research databases from our medical foundation. METHODS: We conducted a propensity score-matched cohort study based on our multi-institution medical organization research database. From January 2007 to January 2018, a total of 413 patients (photon: 349; proton: 64) who were diagnosed with HCC and primarily treated with radiotherapy with curative intent were enrolled. Overall survival (OS) and radiation-induced liver disease (RILD) were assessed. Stratified analysis was also performed to evaluate the heterogeneous effects of the two arms. RESULTS: A total of 110 patients (photon: 55; proton: 55) were analyzed in the propensity-matched series. The matched groups were balanced for baseline tumor risk factors. Cox regression analysis revealed a significant survival benefit in the proton group (p = 0.032, HR 0.56, 95% CI 0.33-0.96). The median overall survival in the proton group was not reached and that in the photon group was 17.4 months. The biological equivalent dose of radiotherapy was significantly higher in the proton group than in the photon group (median, 96.56 Gray [relative biological effectiveness] vs. 62.5 Gray, p < 0.001). The risk of RILD was significantly lower in the proton group (11.8% vs. 36%, p = 0.004). CONCLUSIONS: Proton radiotherapy could deliver a higher radiation dose than photon radiotherapy without increasing the risk of RILD and result in a better overall survival rate for those diagnosed with HCC and treated with radiotherapy with curative intent.


Subject(s)
Carcinoma, Hepatocellular/radiotherapy , Liver Neoplasms/radiotherapy , Photons/therapeutic use , Proton Therapy , Aged , Carcinoma, Hepatocellular/mortality , Cohort Studies , Female , Humans , Liver/radiation effects , Liver Neoplasms/mortality , Male , Middle Aged , Photons/adverse effects , Propensity Score , Proton Therapy/adverse effects , Radiation Injuries/epidemiology , Radiotherapy Dosage
19.
J Aging Phys Act ; 28(6): 875-882, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-32485665

ABSTRACT

Engaging in healthy eating and active living is an effective strategy for preventing noncommunicable diseases in older populations. The purposes were to compare the prevalence rates across countries and explore health factors associated with healthy eating and active living. The data were retrieved from a cross-sectional study conducted by the International Social Survey Program (2011 Health and Healthcare), with structured questionnaire surveys in 32 countries. The results showed that 38.42% reported active living and 39.11% reported healthy eating among 11,250 total respondents. Older adults with a long-standing illness or obesity who felt that they were not overcoming problems and had lost confidence were less likely to engage in healthy behavior. Perceived general health had a positive association with the odds of engaging in healthy eating and active living. The international comparisons provide a reference for local governments to decrease health disparities. Inspiring self-awareness about health might encourage older adults to pursue healthy lifestyles.

20.
J Chem Inf Model ; 59(9): 3703-3713, 2019 09 23.
Article in English | MEDLINE | ID: mdl-31393721

ABSTRACT

A new molecular data structure and molecular structure operation algorithms are proposed for general purpose molecular design. The data structure allows for a variety of molecular operations for creating new molecules. Two types of molecular operations were developed, unimolecular and bimolecular operations. In unimolecular operations, a child molecule can be created from a parent via addition of a functional group, deletion of a fragment, mutation of an atom, etc. In bimolecular operations, children molecules are generated from two parent molecules through combination or crossover (hybridization). These molecular operations are essential for the creation and modification of molecules for the purpose of molecular design. The data structure is capable of representing linear, branched, multifunctional, and multivalent compounds. Algorithms are developed for deriving the molecular data structure of a molecule from its atomic coordinates and vice versa. We show that this new molecular data structure and the developed algorithms, referred to as Molecular Assembling and Representation Suite, allow one to generate a comprehensive library of new molecules via performing every possible molecular structure modification.


Subject(s)
Small Molecule Libraries/chemistry , Algorithms , Cheminformatics/methods , Computer Simulation , Drug Design , Models, Chemical , Models, Molecular , Molecular Structure
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