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1.
Biomed Eng Online ; 22(1): 88, 2023 Sep 05.
Article in English | MEDLINE | ID: mdl-37670316

ABSTRACT

BACKGROUND: Robot-assisted gait training is incorporated into guidelines for stroke rehabilitation. It is a promising tool combined with conventional therapy for low ambulatory patients. The heavy weight and bulky appearance of a robotic exoskeleton limits its practicality. On the other hand, soft robotic exosuit (SRE) based on its light weight and inconspicuous property, is better tolerated by patients in daily life. The aim of this study is to review the efficacy of the SRE with regard to walking ability and biomechanical properties in stroke patients. METHODS: Electronic searches were carried out in PubMed, Embase, Cochrane Library, Web of Science, and the Physiotherapy Evidence Database. Clinical trials that investigated the effectiveness of SREs on ambulation ability in patients with post-stroke hemiparesis were eligible. Qualitative data synthesis was subsequently performed. RESULTS: Nine studies were identified as relevant, involving a total of 83 patients. For the assessment of SRE efficacy, outcome measures were walking ability and biomechanical properties. In terms of both immediate effect and training effect, SREs improved the walking speed, walking distance, peak ankle dorsiflexion angle during swing phase, peak paretic propulsion, stride length and compensated gait in stroke patients. CONCLUSIONS: SRE improved the ambulation ability of stroke patients in terms of walking ability and biomechanical properties. The small number of studies limits the generalizability of interpretation. More controlled studies with better quality are required to reach a more solid conclusion on this issue.


Subject(s)
Robotics , Stroke Rehabilitation , Stroke , Humans , Gait , Databases, Factual
2.
J Enzyme Inhib Med Chem ; 38(1): 2166039, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36683274

ABSTRACT

Inhibiting a specific target in cancer cells and reducing unwanted side effects has become a promising strategy in pancreatic cancer treatment. MAP4K4 is associated with pancreatic cancer development and correlates with poor clinical outcomes. By phosphorylating MKK4, proteins associated with cell apoptosis and survival are translated. Therefore, inhibiting MAP4K4 activity in pancreatic tumours is a new therapeutic strategy. Herein, we performed a structure-based virtual screening to identify MAP4K4 inhibitors and discovered the compound F389-0746 with a potent inhibition (IC50 120.7 nM). The results of kinase profiling revealed that F389-0746 was highly selective to MAP4K4 and less likely to cause side effects. Results of in vitro experiments showed that F389-0746 significantly suppressed cancer cell growth and viability. Results of in vivo experiments showed that F389-0746 displayed comparable tumour growth inhibition with the group treated with gemcitabine. These findings suggest that F389-0746 has promising potential to be further developed as a novel pancreatic cancer treatment.


Subject(s)
Antineoplastic Agents , Pancreatic Neoplasms , Protein Kinase Inhibitors , Protein Serine-Threonine Kinases , Humans , Cell Line, Tumor , Gemcitabine/chemistry , Gemcitabine/pharmacology , Intracellular Signaling Peptides and Proteins , Pancreatic Neoplasms/enzymology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Computer Simulation , Pancreatic Neoplasms
3.
J Enzyme Inhib Med Chem ; 38(1): 2212326, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37190931

ABSTRACT

Class II histone deacetylases (HDACs) are considered as potential targets to treat Alzheimer's disease (AD). Previously, C-3 substituted phenothiazine-containing compounds with class II HDAC-inhibiting activities was found to promote neurite outgrowth. This study replaced phenothiazine moiety with phenoxazine that contains many C-3 and C-4 substituents. Some resulting compounds bearing the C-4 substituent on a phenoxazine ring displayed potent class II HDAC inhibitory activities. Structure-activity relationship (SAR) of these compounds that inhibited HDAC isoenzymes was disclosed. Molecular modelling analysis demonstrates that the potent activities of C-4 substituted compounds probably arise from π-π stacked interactions between these compounds and class IIa HDAC enzymes. One of these, compound 7d exhibited the most potent class II HDAC inhibition (IC50= 3-870 nM). Notably, it protected neuron cells from H2O2-induced neuron damage at sub-µM concentrations, but with no significant cytotoxicity. These findings show that compound 7d is a lead compound for further development of anti-neurodegenerative agents.


Subject(s)
Antineoplastic Agents , Hydroxamic Acids , Hydroxamic Acids/pharmacology , Histone Deacetylase Inhibitors/pharmacology , Hydrogen Peroxide/pharmacology , Structure-Activity Relationship , Histone Deacetylases/metabolism , Antineoplastic Agents/pharmacology , Histone Deacetylase 1/pharmacology , Cell Proliferation
4.
Bioorg Chem ; 121: 105675, 2022 04.
Article in English | MEDLINE | ID: mdl-35182882

ABSTRACT

Fms-like tyrosine kinase 3 (FLT3) is considered a promising therapeutic target for acute myeloid leukemia (AML) in the clinical. However, monotherapy with FLT3 inhibitor is usually accompanied by drug resistance. Dual inhibitors might be therapeutically beneficial to patients with AML due to their ability to overcome drug resistance. Mitogen-activated protein kinase (MAPK)-interacting kinases (MNKs) phosphorylate eukaryotic translation initiation factor 4E (eIF4E), which brings together the RAS/RAF/ERK and PI3K/AKT/mTOR oncogenic pathways. Therefore, dual inhibition of FLT3 and MNK2 might have an additive effect against AML. Herein, a structure-based virtual screening approach was performed to identify dual inhibitors of FLT3 and MNK2 from the ChemDiv database. Compound K783-0308 was identified as a dual inhibitor of FLT3 and MNK2 with IC50 values of 680 and 406 nM, respectively. In addition, the compound showed selectivity for both FLT3 and MNK2 in a panel of 82 kinases. The structure-activity relationship analysis and common interactions revealed interactions between K783-0308 analogs and FLT3 and MNK2. Furthermore, K783-0308 inhibited MV-4-11 and MOLM-13 AML cell growth and induced G0/G1 cell cycle arrest. Taken together, the dual inhibitor K783-0308 showed promising results and can be potentially optimized as a lead compound for AML treatment.


Subject(s)
Leukemia, Myeloid, Acute , fms-Like Tyrosine Kinase 3 , Apoptosis , Cell Line, Tumor , Cell Proliferation , Humans , Intracellular Signaling Peptides and Proteins , Leukemia, Myeloid, Acute/drug therapy , Mutation , Phosphatidylinositol 3-Kinases , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Protein Serine-Threonine Kinases
5.
J Enzyme Inhib Med Chem ; 37(1): 226-235, 2022 Dec.
Article in English | MEDLINE | ID: mdl-34894949

ABSTRACT

Bruton tyrosine kinase (BTK) is linked to multiple signalling pathways that regulate cellular survival, activation, and proliferation. A covalent BTK inhibitor has shown favourable outcomes for treating B cell malignant leukaemia. However, covalent inhibitors require a high reactive warhead that may contribute to unexpected toxicity, poor selectivity, or reduced effectiveness in solid tumours. Herein, we report the identification of a novel noncovalent BTK inhibitor. The binding interactions (i.e. interactions from known BTK inhibitors) for the BTK binding site were identified and incorporated into a structure-based virtual screening (SBVS). Top-rank compounds were selected and testing revealed a BTK inhibitor with >50% inhibition at 10 µM concentration. Examining analogues revealed further BTK inhibitors. When tested across solid tumour cell lines, one inhibitor showed favourable inhibitory activity, suggesting its potential for targeting BTK malignant tumours. This inhibitor could serve as a basis for developing an effective BTK inhibitor targeting solid cancers.


Subject(s)
Agammaglobulinaemia Tyrosine Kinase/antagonists & inhibitors , Antineoplastic Agents/pharmacology , Protein Kinase Inhibitors/pharmacology , Small Molecule Libraries/pharmacology , Agammaglobulinaemia Tyrosine Kinase/metabolism , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/chemistry , Small Molecule Libraries/chemical synthesis , Small Molecule Libraries/chemistry , Structure-Activity Relationship
6.
J Nat Prod ; 84(1): 1-10, 2021 01 22.
Article in English | MEDLINE | ID: mdl-33393294

ABSTRACT

Acute myeloid leukemia (AML) is an aggressive disease with a poor prognosis and a high degree of relapse seen in patients. Overexpression of FMS-like tyrosine kinase 3 (FLT3) is associated with up to 70% of AML patients. Wild-type FLT3 induces proliferation and inhibits apoptosis in AML cells, while uncontrolled proliferation of FLT3 kinase activity is also associated with FLT3 mutations. Therefore, inhibiting FLT3 activity is a promising AML therapy. Flavonoids are a group of phytochemicals that can target protein kinases, suggesting their potential antitumor activities. In this study, several plant-derived flavonoids have been identified with FLT3 inhibitory activity. Among these compounds, compound 40 (5,7,4'-trihydroxy-6-methoxyflavone) exhibited the most potent inhibition against not only FLT3 (IC50 = 0.44 µM) but also FLT3-D835Y and FLT3-ITD mutants (IC50 = 0.23 and 0.39 µM, respectively). The critical interactions between the FLT3 binding site and the compounds were identified by performing a structure-activity relationship analysis. Furthermore, the results of cellular assays revealed that compounds 28, 31, 32, and 40 exhibited significant cytotoxicity against two human AML cell lines (MOLM-13 and MV-4-11), and compounds 31, 32, and 40 resulted in cell apoptosis and G0/G1 cell cycle arrest. Collectively, these flavonoids have the potential to be further optimized as FLT3 inhibitors and provide valuable chemical information for the development of new AML drugs.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Flavonoids/pharmacology , Leukemia, Myeloid, Acute/drug therapy , Mutation/drug effects , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , fms-Like Tyrosine Kinase 3/therapeutic use , Antineoplastic Agents/chemistry , Humans , Leukemia, Myeloid, Acute/genetics , Protein Kinase Inhibitors/chemistry , Xenograft Model Antitumor Assays , fms-Like Tyrosine Kinase 3/antagonists & inhibitors , fms-Like Tyrosine Kinase 3/chemistry , fms-Like Tyrosine Kinase 3/genetics , fms-Like Tyrosine Kinase 3/pharmacology
7.
J Enzyme Inhib Med Chem ; 36(1): 98-108, 2021 Dec.
Article in English | MEDLINE | ID: mdl-33167727

ABSTRACT

The STE20 kinase family is a complex signalling cascade that regulates cytoskeletal organisation and modulates the stress response. This signalling cascade includes various kinase mediators, such as TAOK1 and MAP4K5. The dysregulation of the STE20 kinase pathway is linked with cancer malignancy. A small-molecule inhibitor targeting the STE20 kinase pathway has therapeutic potential. In this study, a structure-based virtual screening (SBVS) approach was used to identify potential dual TAOK1 and MAP4K5 inhibitors. Enzymatic assays confirmed three potential dual inhibitors (>50% inhibition) from our virtual screening, and analysis of the TAOK1 and MAP4K5 binding sites indicated common interactions for dual inhibition. Compound 1 revealed potent inhibition of colorectal and lung cancer cell lines. Furthermore, compound 1 arrested cancer cells in the G0/G1 phase, which suggests the induction of apoptosis. Altogether, we show that the STE20 signalling mediators TAOK1 and MAP4K5 are promising targets for drug research.


Subject(s)
Antineoplastic Agents/pharmacology , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Drug Screening Assays, Antitumor , Humans , Molecular Structure , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/chemistry , Protein Serine-Threonine Kinases/metabolism , Structure-Activity Relationship , Tumor Cells, Cultured
8.
J Nat Prod ; 83(10): 2967-2975, 2020 10 23.
Article in English | MEDLINE | ID: mdl-33026809

ABSTRACT

Excessive eIF4E phosphorylation by mitogen-activated protein kinase (MAPK)-interacting kinases 1 and 2 (MNK1 and MNK2; collectively, MNKs) has been associated with oncogenesis. The overexpression of eIF4E in acute myeloid leukemia (AML) is related to cancer cell growth and survival. Thus, the inhibition of MNKs and eIF4E phosphorylation are potential therapeutic strategies for AML. Herein, a structure-based virtual screening approach was performed to identify potential MNK inhibitors from natural products. Three flavonoids, apigenin, hispidulin, and luteolin, showed MNK2 inhibitory activity with IC50 values of 308, 252, and 579 nM, respectively. A structure-activity relationship analysis was performed to disclose the molecular interactions. Furthermore, luteolin exhibited substantial inhibitory efficacy against MNK1 (IC50 = 179 nM). Experimental results from cellular assays showed that hispidulin and luteolin inhibited the growth of MOLM-13 and MV4-11 AML cells by downregulating eIF4E phosphorylation and arresting the cell cycle at the G0/G1 phase. Therefore, hispidulin and luteolin showed promising results as lead compounds for the potential treatment for AML.


Subject(s)
Flavonoids , Intracellular Signaling Peptides and Proteins , Leukemia, Myeloid, Acute , Protein Serine-Threonine Kinases , Cell Cycle , Cell Line, Tumor , Humans , Molecular Structure , Phosphorylation , Protein Kinase Inhibitors , Structure-Activity Relationship
9.
Bioorg Chem ; 98: 103729, 2020 05.
Article in English | MEDLINE | ID: mdl-32179284

ABSTRACT

Leucettamine B is a natural product found in marine sponge Leucetta microraphis. Several of analogs of its family, such as aplysinopsine and clathridine, are medicinally active molecules which have applications in many pharmaceuticals and healthcare products; however, thus far, leucettamine B has not been studied. In this report, we describe the synthesis of a new class of analogs of leucettamine B obtained by Knoevenagel condensation using a microwave reactor. The 25 newly synthesized compounds were tested against MDA-MB-468, SW480, and Mahlavu cell lines for anticancer activity. Among them, the carborane-based compound (Z)-5-(benzo[d][1,3]dioxol-5-ylmethylene)-3-(1-closo-carboranyl)-2-thioxo -thiazolidin-4-one (49) and (Z)-5-(benzo[d][1,3]dioxol-5-ylmethylene)-3-(2-(pyrrolidin-1-yl)ethyl)-2-thioxothiazolidin-4-one (31) derivatives were found to have the most potential for use against tumor cells. The carborane derivative 49 had the lowest IC50 value against the SW480 cell line (4.7 µM) and the Mahlavu (6.6 µM) cell line. Furthermore, compound 31 also had a low IC50 value against SW480 (7.5 µM). Our research shows that leucettamine B analogs might have potential for use in cancer chemotherapy.


Subject(s)
Antineoplastic Agents/pharmacology , Boranes/pharmacology , Drug Design , Imidazoles/pharmacology , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Boranes/chemical synthesis , Boranes/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Chlorocebus aethiops , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Imidazoles/chemical synthesis , Imidazoles/chemistry , Molecular Structure , Structure-Activity Relationship , Vero Cells
10.
Mar Drugs ; 18(8)2020 Jul 23.
Article in English | MEDLINE | ID: mdl-32718084

ABSTRACT

13-Acetoxysarcocrassolide (13-AC), a marine cytotoxic product isolated from the alcyonacean coral Lobophytum crassum, exhibited potent antitumor and immunostimulant effects as reported in previous studies. However, the 13-AC antitumor mechanism of action against oral cancer cells remains unclear. The activity of 13-AC against Ca9-22 cancer cells was determined using MTT assay, flow cytometric analysis, immunofluorescence, immunoprecipitation, Western blotting, and siRNA. 13-AC induced apoptosis in oral cancer cells Ca9-22 through the disruption of mitochondrial membrane potential (MMP) and the stimulation of reactive oxygen species (ROS) generation. It increased the expression of apoptosis- and DNA damage-related proteins in a concentration- and time-dependent manner. It exerted potent antitumor effect against oral cancer cells, as demonstrated by the in vivo xenograft animal model. It significantly reduced the tumor volume (55.29%) and tumor weight (90.33%). The pretreatment of Ca9-22 cells with N-acetylcysteine (NAC) inhibited ROS production resulting in the attenuation of the cytotoxic activity of 13-AC. The induction of the Keap1-Nrf2 pathway and the promotion of p62/SQSTM1 were observed in Ca9-22 cells treated with 13-AC. The knockdown of p62 expression by siRNA transfection significantly attenuated the effect of 13-AC on the inhibition of cell viability. Our results indicate that 13-AC exerted its cytotoxic activity through the promotion of ROS generation and the suppression of the antioxidant enzyme activity. The apoptotic effect of 13-AC was found to be mediated through the interruption of the Keap1/Nrf2/p62/SQSTM1 pathway, suggesting its potential future application as an anticancer agent.


Subject(s)
Antineoplastic Agents/pharmacology , Diterpenes/pharmacology , Kelch-Like ECH-Associated Protein 1/metabolism , Mouth Neoplasms/drug therapy , NF-E2-Related Factor 2/metabolism , Sequestosome-1 Protein/metabolism , Animals , Apoptosis/drug effects , Cell Proliferation/drug effects , HCT116 Cells , HeLa Cells , Humans , MCF-7 Cells , Male , Membrane Potential, Mitochondrial/drug effects , Mice, Nude , Mouth Neoplasms/enzymology , Mouth Neoplasms/genetics , Mouth Neoplasms/pathology , Reactive Oxygen Species/metabolism , Sequestosome-1 Protein/genetics , Signal Transduction , Tumor Burden/drug effects , Xenograft Model Antitumor Assays
11.
Molecules ; 25(23)2020 Nov 30.
Article in English | MEDLINE | ID: mdl-33266202

ABSTRACT

Alzheimer's disease (AD), which is among the most prevalent neurodegenerative diseases, manifests as increasing memory loss and cognitive decline. Tau phosphorylation and aggregation are strongly linked to neurodegeneration, as well as associated with chronic neuroinflammatory processes. The anti-inflammation effects of natural products have led to wide recognition of their potential for use in treating and preventing AD. This study investigated whether eupatin, a polymethoxyflavonoid found in Artemisia species, has inhibitory effects on neuroinflammation and tau phosphorylation. We treated mouse macrophages and microglia cells with lipopolysaccharides (LPSs) to activate inflammatory signals, and we treated neuronal cells with a protein phosphatase 2A inhibitor, okadaic acid (OA), or transfection with pRK5-EGFP-Tau P301L plasmid to induce tau phosphorylation. The results indicated that eupatin significantly reduced the LPS-induced protein expression and phosphorylation of p65 and inducible nitric oxide synthase as well as downstream products interleukin 6 and nitrite, respectively. Furthermore, eupatin markedly inhibited the expression of phospho-tau in response to OA treatment and plasmid transfection. We discovered that this inhibition was achieved through the inhibition of glycogen synthase kinase 3ß (GSK3ß), and molecular docking results suggested that eupatin can sufficiently bind to the GSK3ß active site. Our results demonstrate that eupatin has neuroprotective effects, making it suitable for AD treatment.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Flavonoids/pharmacology , Macrophages/drug effects , Microglia/drug effects , Neuroprotective Agents/pharmacology , Plant Extracts/pharmacology , tau Proteins/antagonists & inhibitors , Animals , Apoptosis , Macrophages/metabolism , Macrophages/pathology , Mice , Microglia/metabolism , Microglia/pathology , Molecular Docking Simulation , Phosphorylation , Phytotherapy , Zingiberaceae/chemistry
12.
J Biomed Sci ; 26(1): 42, 2019 May 27.
Article in English | MEDLINE | ID: mdl-31133011

ABSTRACT

Protein ubiquitination is an important mechanism for regulating the activity and levels of proteins under physiological conditions. Loss of regulation by protein ubiquitination leads to various diseases, such as cancer. Two types of enzymes, namely, E1/E2/E3 ligases and deubiquitinases, are responsible for controlling protein ubiquitination. The ubiquitin-specific peptidases (USPs) are the main members of the deubiquitinase family. Many studies have addressed the roles of USPs in various diseases. An increasing number of studies have indicated that USPs are critical for cancer progression, and some USPs have been used as targets to develop inhibitors for cancer prevention. Herein we collect and organize most of the recent studies on the roles of USPs in cancer progression and discuss the development of USP inhibitors for cancer therapy in the future.


Subject(s)
Disease Progression , Neoplasms/drug therapy , Neoplasms/metabolism , Ubiquitin-Specific Proteases/antagonists & inhibitors , Ubiquitin-Specific Proteases/metabolism , Humans , Ubiquitination
13.
Clin Transplant ; 33(12): e13735, 2019 12.
Article in English | MEDLINE | ID: mdl-31628673

ABSTRACT

INTRODUCTION: Patients with end-stage renal disease (ESRD) have a higher incidence of coronary artery disease (CAD). Hence, it is crucial to evaluate CAD before renal transplantation. This study compares the utility of pharmacologic single-photon emission computed-tomography (SPECT) imaging directly to coronary angiography for diagnosis of CAD with correlation to cardiovascular risk factors. METHOD: Retrospective review of asymptomatic renal failure patients who underwent both SPECT and coronary angiography to identify obstructive CAD between the years 2008-2016. Ninety-four ESRD subjects were evaluated. RESULTS: Myocardial perfusion SPECT study found, when compared to coronary angiography demonstrated for CAD, the sensitivity of 93.3% with a specificity of 73.4%. Importantly, the negative predictive value for coronary artery disease was 96%. With seven or more cardiac risk factors, 66.7% of patients had obstructive coronary artery disease. Among all the risk factors examined, patients with a previous history of coronary artery disease had a 68% risk of obstructive coronary artery disease. CONCLUSION: Comparing myocardial perfusion imaging SPECT findings with coronary angiography in patients with ESRD, a sensitivity of 93.3% and a specificity of 73% were observed. Of all the risk factors examined, patient with the previous history of CAD was the single most significant risk factor for CAD in 68% of cases.


Subject(s)
Cardiovascular Diseases/pathology , Coronary Angiography/methods , Kidney Failure, Chronic/complications , Myocardial Perfusion Imaging/methods , Cardiovascular Diseases/diagnostic imaging , Cardiovascular Diseases/etiology , Cross-Sectional Studies , Female , Follow-Up Studies , Humans , Kidney Failure, Chronic/diagnostic imaging , Kidney Transplantation , Male , Middle Aged , Prognosis , Retrospective Studies , Risk Factors
14.
Bioorg Chem ; 91: 103119, 2019 10.
Article in English | MEDLINE | ID: mdl-31349117

ABSTRACT

The study is focused on the design and synthesis of amide tethered quinoline-resorcinol hybrid constructs as a new class of HSP90 inhibitor. In-vitro studies of the synthetic compounds led to the identification of compound 11, which possesses potent cell growth inhibitory effects against HCT116, Hep3B and PC-3 cell lines, exerted through HSP90 inhibition. Compound 11 triggers degradation of HSP90 client proteins along with concomitant induction of HSP70, demonstrates apoptosis inducing ability and causes G2M phase cell cycle arrest in PC-3 cells. Molecular modeling was used to dock compound 11 into the HSP90 active site and key interactions with the amino acid residues of the HSP90 chaperone protein were determined.


Subject(s)
Amides/pharmacology , Antineoplastic Agents/pharmacology , HSP90 Heat-Shock Proteins/antagonists & inhibitors , Prostatic Neoplasms/drug therapy , Quinolines/pharmacology , Resorcinols/pharmacology , Amides/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , HSP90 Heat-Shock Proteins/metabolism , Humans , Male , Models, Molecular , Molecular Structure , PC-3 Cells , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Quinolines/chemistry , Resorcinols/chemistry , Structure-Activity Relationship , Tumor Cells, Cultured
15.
Appl Microbiol Biotechnol ; 103(13): 5285-5299, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31028439

ABSTRACT

Bacterial meningitis is a severe disease that is fatal to one-third of patients. The major cause of meningitis in neonates is Escherichia coli (E. coli) K1. This bacterium synthesizes an outer membrane protein A (OmpA) that is responsible for the adhesion to (and invasion of) endothelial cells. Thus, the OmpA protein represents a potential target for developing diagnostic and therapeutic agents for meningitis. In this study, we expressed recombinant OmpA proteins with various molecular weights in E. coli. The sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was performed to check the molecular size of OmpA's full length (FL) and truncated proteins. OmpA-FL protein was purified for immunizing chickens to produce immunoglobulin yolk (IgY) antibodies. We applied phage display technology to construct antibody libraries (OmpA-FL scFv-S 1.1 × 107 and OmpA-FL scFv-L 5.01 × 106) to select specific anti-OmpA-FL scFv antibodies; these were characterized by their binding ability to recombinant or endogenous OmpA using ELISA, immunofluorescent staining, and confirmed with immunoblotting. We found 12 monoclonal antibodies that react to OmpA fragments; seven scFvs recognize fragments spanning amino acid (aa) residues 1-346, aa 1-287, aa 1-167, and aa 60-192, while five scFvs recognize fragments spanning aa 1-346 and aa 1-287 only. Two fragments (aa 246-346 and aa 287-346) were not recognized with any of the 12 scFvs. Together, the data suggest three antigenic epitopes (60 aa-160 aa, 161 aa-167 aa, 193 aa-245 aa) recognized by monoclonal antibodies. These scFv antibodies show strong reactivity against OmpA proteins. We believe that antibodies show promising diagnostic agents for E. coli K1 meningitis.


Subject(s)
Antibodies, Monoclonal/immunology , Bacterial Outer Membrane Proteins/immunology , Escherichia coli Infections/diagnosis , Meningitis/diagnosis , Single-Chain Antibodies/immunology , Animals , Antibodies, Monoclonal/isolation & purification , Bacterial Outer Membrane Proteins/genetics , Cell Surface Display Techniques , Chickens/immunology , Enzyme-Linked Immunosorbent Assay , Epitopes/immunology , Escherichia coli/genetics , Escherichia coli Infections/immunology , Female , Immunization , Immunoglobulins/immunology , Meningitis/immunology , Meningitis/microbiology , Recombinant Proteins/immunology , Single-Chain Antibodies/genetics
16.
Emerg Radiol ; 24(6): 667-674, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28801805

ABSTRACT

PURPOSE: The purpose of this study was to validate the observation that pulmonary artery (PA) enhancement is often decreased in sickle cell disease (SCD) patients imaged with MDCT for suspected pulmonary embolism and determine whether contrast infusion parameters are accountable for lower enhancement levels. MATERIALS AND METHODS: Retrospective comparison of 35 adult SCD patients imaged for suspected pulmonary embolism (PE) in our emergency department using 128-slice dual source MDCT scanner to 34 age and weight matched adult controls. Bolus tracking data was recorded, and enhancement levels of the main PA and descending aorta were measured. Electronic records were reviewed for demographics, imaging and lab correlation, and infusion parameters. RESULTS: Age, weight, contrast infusion rate, and contrast volume were similar for both SCD and control patients. SCD patients had significantly lower main PA enhancement (mean 233 HU, range 151-361 HU) than the control subjects (mean 290 HU, range 138-487 HU) (p < 0.001). Most (74%) SCD subjects had PA enhancement that was <250 HU, while most (68%) control patients had PA enhancement ≥250 HU. Change in PA enhancement per second during bolus tracking was lower in SCD patients (12 HU/s, range -24 to 91 HU/s) than control patients (mean 30 HU/s, range -37 to 138 HU/s), although the difference was not statistically significant (p = 0.08). Hemoglobin levels were significantly lower in the SCD cohort (p < 0.001). CONCLUSION: In this series of adult SCD patients with suspected PE imaged with MDCT, main PA enhancement level was lower than controls. Quality improvement investigations should focus on protocol optimization to improve enhancement quality and likelihood of a definitive diagnosis.


Subject(s)
Anemia, Sickle Cell/complications , Computed Tomography Angiography/methods , Pulmonary Embolism/diagnostic imaging , Pulmonary Embolism/etiology , Adult , Case-Control Studies , Contrast Media , Female , Humans , Male , Middle Aged , Retrospective Studies , Triiodobenzoic Acids
17.
Int Orthop ; 41(11): 2337-2343, 2017 11.
Article in English | MEDLINE | ID: mdl-28840305

ABSTRACT

PURPOSE: Treating fracture nonunion with endothelial progenitor cells (EPCs) is a promising approach. Nevertheless, the effect of different EPC-related cell populations remains unclear. In this study, we compared the therapeutic potential of early (E-EPCs) and late EPCs (L-EPCs). METHODS: Male Fischer 344 rats were used for cell isolation and in vivo experiments. Bone marrow-derived E-EPCs and L-EPCs were kept in culture for seven to ten days and four weeks, respectively. For each treatment group, we seeded one million cells on a gelatin scaffold before implantation in a segmental defect created in a rat femur; control animals received a cell-free scaffold. Bone healing was monitored via radiographs for up to ten weeks after surgery. In vitro, secretion of vascular endothelial growth factor (VEGF) and bone morphogenetic protein (BMP)-2 was quantified by ELISA for both cell populations. Tube formation assays were also performed. RESULTS: Final radiographs showed complete (four out of five rats) or partial (one out of five rats) union with E-EPC treatment. In contrast, complete healing was achieved in only one of five animals after L-EPC implantation, while control treatment resulted in nonunion in all animals. In vitro, E-EPCs released more VEGF, but less BMP-2 than L-EPCs. In addition, L-EPCs formed longer and more mature tubules on basement membrane matrix than E-EPCs. However, co-culture with primary osteoblasts stimulated tubulogenesis of E-EPCs while inhibiting that of L-EPCs. CONCLUSIONS: We demonstrated that bone marrow-derived E-EPCs are a better alternative than L-EPCs for treatment of nonunion. We hypothesize that the expression profile of E-EPCs and their adaptation to the local environment contribute to superior bone healing.


Subject(s)
Endothelial Progenitor Cells/transplantation , Fracture Healing/drug effects , Fractures, Ununited/therapy , Animals , Bone Morphogenetic Protein 2/metabolism , Cell Culture Techniques , Endothelial Progenitor Cells/cytology , Enzyme-Linked Immunosorbent Assay , Male , Rats , Vascular Endothelial Growth Factor A/metabolism
18.
J Prosthet Dent ; 116(1): 74-9, 2016 Jul.
Article in English | MEDLINE | ID: mdl-26946919

ABSTRACT

STATEMENT OF PROBLEM: Fundamental crown preparation principles are taught and are highly regarded in dental education. Whether tooth preparations made by dental students match these principles is unclear. PURPOSE: The purpose of this retrospective study was to report the total occlusal convergence (TOC) and margin widths of crown preparations clinically prepared by New Zealand predoctoral dental students between 2013 and mid-2015. MATERIAL AND METHODS: A total of 371 stereolithography files of tooth preparations for metal ceramic crowns prepared by predoctoral dental students were extracted from the Technical Services Laboratory database at the University of Otago. The files were put through the preparation measuring software Preppr, with outputs being TOC angles in faciolingual and mesiodistal cross sections and margin widths in facial, lingual, distal, and mesial aspects. Means, standard deviations, 95% confidence intervals, and distributions using box and whisker graphs were calculated and presented. RESULTS: The majority of TOC angles fell within an acceptable range of 10 to 20 degrees; however, the angles ranged from undercuts (<0 degrees) to >60 degrees. The majority of margin widths were between 0.5 and 1 mm, while the maximum was approximately 2 mm and the minimum was 0 mm. CONCLUSIONS: Predoctoral dental students in New Zealand are able to produce literature-recommended TOC angles and margin widths for metal ceramic crowns; however, further attention and training are needed for excessive tooth preparations, mainly in the form of large TOC angles.


Subject(s)
Crowns , Students, Dental , Clinical Competence , Crowns/standards , Crowns/statistics & numerical data , Dental Marginal Adaptation , Dental Prosthesis Design , Humans , New Zealand , Prosthodontics/education , Retrospective Studies , Tooth Preparation, Prosthodontic
19.
J Neuroophthalmol ; 35(4): 387-9, 2015 Dec.
Article in English | MEDLINE | ID: mdl-25996302

ABSTRACT

Eagle syndrome occurs when an elongated styloid process causes otolaryngological or neurological symptoms or signs. We report a patient who had an isolated asymptomatic Horner syndrome that resulted from a pinned internal carotid artery being dynamically injured by an elongated styloid process during chiropractic neck manipulation. There was no evidence of arterial dissection.


Subject(s)
Horner Syndrome/etiology , Ossification, Heterotopic/complications , Temporal Bone/abnormalities , Aged , Carotid Artery, Internal/pathology , Female , Horner Syndrome/diagnosis , Humans , Magnetic Resonance Angiography , Magnetic Resonance Imaging , Manipulation, Chiropractic/adverse effects , Ossification, Heterotopic/etiology , Ossification, Heterotopic/pathology , Temporal Bone/pathology
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