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1.
Article in English | MEDLINE | ID: mdl-38096583

ABSTRACT

OBJECTIVE: Anti-synthetase syndrome (ASyS) patients have heterogeneous clinical manifestations with different initial presentations, complications, and outcomes. This study aimed to assess the clinical characteristics and complications in patients with ASyS, and to identify factors that were associated with the survival of ASyS patients. METHODS: This was a retrospective multicentre longitudinal study. Patients fulfilling either the Connor's criteria or Solomon's criteria for ASyS were recruited. Electronic health records were reviewed until October 2022. Multivariate Cox-regression analysis was used to determine the independent prognostic factors. Auto-antibodies were checked by commercial immunoassays. RESULTS: A total of 205 patients (anti-Jo-1 49.3%, anti-PL-7 19.0%, anti-EJ 11.2%, anti-PL-12 10.2% and anti-OJ 3.4%) were included. The median follow-up time was 4 years. The time from symptoms onset to diagnosis was significantly longer for non-anti-Jo1 patients (median 5 vs 3 months). Common initial presentations included myositis (56.1%), arthritis (54.6%), and interstitial lung disease (ILD) (54.1%). Patients with anti-Jo-1 had significantly higher muscle enzyme levels and more arthritis. All patients with anti-EJ would develop ILD on follow-up and malignancy was noted in 28.6% of the anti-OJ positive patients. 15.6% of the patients died and pulmonary diseases (ILD or pneumonia) were the major causes. Age at diagnosis, malignancy and rapidly progressive-ILD were independently associated with mortality, while joint manifestation was a protective factor. CONCLUSION: In view of the heterogeneity of clinical presentation of ASyS, high index of suspicion and early checking of specific autoantibodies might help prompt diagnosis of ASyS and detection of related complications.

2.
Article in English | MEDLINE | ID: mdl-37947324

ABSTRACT

OBJECTIVES: To study the effect of SARS-CoV2 infection on flares of systemic lupus erythematosus (SLE). METHODS: Patients who fulfilled the ACR/SLICC criteria for SLE and had documented COVID-19 between February and November 2022 were identified retrospectively from our hospital COVID-19 registry. SLE controls who did not have SARS-CoV2 infection were randomly matched for age, sex and the time of infection in a 2:1 ratio with those infected. The primary outcome of interest was clinical flare of SLE within 90 days of COVID-19. The rate of SLE flares (mild/moderate or severe) was compared between SARS-CoV2-infected SLE patients and controls. RESULTS: 91 SLE patients with COVID-19 (age 48.6 ± 14.0 years; 95.6% women) and 182 SLE controls (age 48.7 ± 13.8 years; 95.6% women) were studied. Eleven of 91 (12.1%) SARS-CoV2-infected patients had serious manifestations. One (1.1%) patient died and 7(7.7%) developed severe complications. Within 90 days of SARS-CoV2 infection, 14(15.4%) patients developed mild/moderate clinical SLE flares and 2(2.2%) patients had severe SLE flares. The incidence of SLE flares in SARS-CoV2-infected patients was significantly higher than those without the infection (17.6% vs 5.5%; odds ratio 3.67[1.59-8.46]; p = 0.001). The changes in anti-dsDNA and complement levels, however, were not significantly different between the two groups. Among SARS-CoV2-infected SLE patients, those with clinical SLE flares had significantly lower C3 values (p = 0.004) before the infection than those without. CONCLUSION: Clinical flares within 90 days were significantly more common in SLE patients infected with SARS-CoV2 than matched non-infected SLE controls.

3.
Plant Dis ; 107(7): 2039-2053, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36428260

ABSTRACT

Brown root rot disease (BRRD), caused by Phellinus noxius, is an important tree disease in tropical and subtropical areas. To improve chemical control of BRRD and deter emergence of fungicide resistance in P. noxius, this study investigated control efficacies and systemic activities of fungicides with different modes of action. Fourteen fungicides with 11 different modes of action were tested for inhibitory effects in vitro on 39 P. noxius isolates from Taiwan, Hong Kong, Malaysia, Australia, and Pacific Islands. Cyproconazole, epoxiconazole, and tebuconazole (Fungicide Resistance Action Committee [FRAC] 3, target-site G1) inhibited colony growth of P. noxius by 99.9 to 100% at 10 ppm and 97.7 to 99.8% at 1 ppm. The other effective fungicide was cyprodinil + fludioxonil (FRAC 9 + 12, target-site D1 + E2), which showed growth inhibition of 96.9% at 10 ppm and 88.6% at 1 ppm. Acropetal translocation of six selected fungicides was evaluated in bishop wood (Bischofia javanica) seedlings by immersion of the root tips in each fungicide at 100 ppm, followed by liquid or gas chromatography tandem mass spectrometry analyses of consecutive segments of root, stem, and leaf tissues at 7 and 21 days posttreatment. Bidirectional translocation of the fungicides was also evaluated by stem injection of fungicide stock solutions. Cyproconazole and tebuconazole were the most readily absorbed by roots and efficiently transported acropetally. Greenhouse experiments suggested that cyproconazole, tebuconazole, and epoxiconazole have a slightly higher potential for controlling BRRD than mepronil, prochloraz, and cyprodinil + fludioxonil. Because all tested fungicides lacked basipetal translocation, soil drenching should be considered instead of trunk injection for their use in BRRD control.


Subject(s)
Basidiomycota , Fungicides, Industrial , Fungicides, Industrial/pharmacology , Epoxy Compounds
4.
Front Pharmacol ; 13: 906625, 2022.
Article in English | MEDLINE | ID: mdl-35935871

ABSTRACT

Pancreatic cancer is amongst the most lethal malignancies, while its poor prognosis could be associated with promotion of autophagy and the tumor immune microenvironment. Studies have confirmed the pro-tumorigenic nature of the cathelicidin family of peptide LL-37 in several types of cancer. However, at higher doses, LL-37 exerts significant cytotoxicity against gastrointestinal cancer cells. In our study, we investigated the anti-tumorigenic potential of LL-37 in pancreatic cancer and the underlying mechanisms. Our results have shown that LL-37 inhibited the growth of pancreatic cancer both in vitro and in vivo. Mechanistic studies have demonstrated that LL-37 induced DNA damage and cell cycle arrest through induction of reactive oxygen species (ROS). Further study indicates that LL-37 suppressed autophagy in pancreatic cancer cells through activation of mTOR signaling, leading to more accumulation of ROS production and induction of mitochondrial dysfunctions. With combined treatment of LL-37 with the mTOR inhibitor rapamycin, LL-37-induced ROS production and cancer cell growth inhibition were attenuated. Subsequent in vivo study has shown that LL-37 downregulated the immunosuppressive myeloid-derived suppressor cells and M2 macrophages while upregulated the anti-cancer effectors CD8+ and CD4+ T cells in the tumor microenvironment. By using an in vitro co-culture system, it was shown that promotion of M2 macrophage polarization would be suppressed by LL-37 with inhibition of autophagy, which possessed significant negative impact on cancer growth. Taken together, our findings implicate that LL-37 could attenuate the development of pancreatic cancer by suppressing autophagy and reprogramming of the tumor immune microenvironment.

5.
Proc Natl Acad Sci U S A ; 119(13): e2200099119, 2022 03 29.
Article in English | MEDLINE | ID: mdl-35324326

ABSTRACT

SignificanceOscillations in intracellular calcium concentration play an essential role in the regulation of multiple cellular processes. In plants capable of root endosymbiosis with nitrogen-fixing bacteria and/or arbuscular mycorrhizal fungi, nuclear localized calcium oscillations are essential to transduce the microbial signal. Although the ion channels required to generate the nuclear localized calcium oscillations have been identified, their mechanisms of regulation are unknown. Here, we combined proteomics and engineering approaches to demonstrate that the calcium-bound form of the calmodulin 2 (CaM2) associates with CYCLIC NUCLEOTIDE GATED CHANNEL 15 (CNGC15s), closing the channels and providing the negative feedback to sustain the oscillatory mechanism. We further unraveled that the engineered CaM2 accelerates early endosymbioses and enhanced root nodule symbiosis but not arbuscular mycorrhization.


Subject(s)
Fabaceae , Mycorrhizae , Calcium , Calcium Signaling/physiology , Mycorrhizae/physiology , Symbiosis
6.
Microorganisms ; 9(10)2021 Oct 19.
Article in English | MEDLINE | ID: mdl-34683497

ABSTRACT

Interactions between a widely used polycationic polymer, polyethyleneimine (PEI), and a Gram-negative bacteria, E. coli, are investigated using atomic force microscopy (AFM) quantitative imaging. The effect of PEI, a known membrane permeabilizer, is characterized by probing both the structure and elasticity of the bacterial cell envelope. At low concentrations, PEI induced nanoscale membrane perturbations all over the bacterial surface. Despite these structural changes, no change in cellular mechanics (Young's modulus) was detected and the growth of E. coli is barely affected. However, at high PEI concentrations, dramatic changes in both structure and cell mechanics are observed. When immobilized on a flat surface, the ability of PEI to alter the membrane structure and reduce bacterial elasticity is diminished. We further probe this immobilization-induced effect by covalently attaching the polymer to the surface of polydopamine nanoparticles (PDNP). The nanoparticle-immobilized PEI (PDNP-PEI), though not able to induce major structural changes on the outer membrane of E. coli (in contrast to the flat surface), was able to bind to and reduce the Young's modulus of the bacteria. Taken together, our data demonstrate that the state of polycationic polymers, whether bound or free-which greatly dictates their overall configuration-plays a major role on how they interact with and disrupt bacterial membranes.

7.
Sci Rep ; 11(1): 10384, 2021 05 17.
Article in English | MEDLINE | ID: mdl-34001924

ABSTRACT

Acupuncture is an important alternative therapy in treating major depressive disorder (MDD), but its efficacy and safety are still not well assessed. This study is the first network meta-analysis exploring the effectiveness and safety of acupuncture, common pharmacological treatments or other non-medication therapies for MDD. Eight databases including PubMed, Embase, Allied and Complementary Medicine Database, Cochrane Library, Wan Fang Data, China National Knowledge Infrastructure, China Biology Medicine disc, and Chongqing VIP Database were searched up to Jan 17, 2021. Articles were screened and selected by two reviewers independently. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess the certainty of the evidence. A total of 71 eligible studies were included. The network analysis results indicated that the combined interventions of electro-acupuncture (EA) with selective serotonin reuptake inhibitors (SSRIs) and manual acupuncture (MA) with SSRIs were more effective in improving depression symptoms compared with acupuncture alone, pharmacological interventions alone, or other inactive groups. Among all the regimens, EA with SSRIs was found to have the highest effect in improving depression symptoms of MDD. In addition, there were slight differences in the estimations of the various treatment durations. The combination of acupuncture and serotonin-norepinephrine reuptake inhibitors (SNRIs) was found to be more effective than SNRIs alone. In conclusion, acupuncture and its combinations could be safe and effective interventions for MDD patients. EA with SSRIs seems to be the most effective intervention among the assessed interventions. Well-designed and large-scale studies with long-term follow-up should be conducted in the future.


Subject(s)
Acupuncture Therapy/methods , Acupuncture , Depressive Disorder, Major/therapy , China/epidemiology , Data Management , Depressive Disorder, Major/epidemiology , Depressive Disorder, Major/pathology , Female , Humans , Male , Network Meta-Analysis , Selective Serotonin Reuptake Inhibitors/therapeutic use
8.
J Am Chem Soc ; 143(2): 973-982, 2021 01 20.
Article in English | MEDLINE | ID: mdl-33403853

ABSTRACT

A cationic water-soluble dipicolylamine (DPA)-containing alkynylplatinum(II) terpyridine complex has been synthesized and employed as a dual-selective probe for the detection of cations and anions. The complex was shown to exhibit a strong binding affinity toward Zn2+, whereas the zinc-bound adduct was found to demonstrate the capability of recognizing pyrophosphate (PPi). As evidenced by molecular modeling and various spectroscopic and spectrometric studies, including HR-ESI mass spectrometry, NMR spectroscopy, PXRD measurements, and UV-vis absorption and emission spectroscopy, a PPi anion was found to be capable of bridging two zinc-bound complex molecules in a clip-shaped fashion, which was further oligomerized through intermolecular Pt···Pt and π-π stacking interactions to form nanofibers with a hexagonal columnar phase. This work provides important insights into not only the construction of aesthetically pleasing supramolecular architectures but also the multifunctional probes, which offer great promise to the fields of biosensing and chemical sensing.

9.
Article in English | WPRIM (Western Pacific) | ID: wpr-892678

ABSTRACT

Background/Aims@#Diarrhea-predominant irritable bowel syndrome (IBS-D) has been previously associated with evidence of immune activation and altered microbiota. Our aim is to assess the effect of the anti-inflammatory agent, mesalazine, on inflammatory gene expression and microbiota composition in IBS-D. @*Methods@#We studied a subset of patients (n = 43) from a previously published 12-week radomized placebo-controlled trial of mesalazine. Mucosal biopsies were assessed by immunohistochemistry and reverse transcription-polymerase chain reaction for a range of markers of inflammation, altered permeability, and sensory receptors including Toll-like receptors (TLRs) at randomization after treatment. All biopsy data were compared to 21 healthy controls. Patient’s stool microbiota composition was analysed through 16S ribosomal RNA sequencing. @*Results@#We found no evidence of increased immune activation compared to healthy controls. However, we did find increased expression of receptors in both sensory pathways and innate immune response including TLR4. Higher TLR4 expression was associated with greater urgency. TLR4 expression correlated strongly with the expression of the receptors bradykinin receptor B2, chemerin chemokine-like receptor 1, and transient receptor potential cation channel, subfamily A, member 1 as well as TLR4’s downstream adaptor myeloid differentiation factor 88. Mesalazine had minimal effect on either gene expression or microbiota composition. @*Conclusions@#Biopsies from a well-characterized IBS-D cohort showed no substantial inflammation. Mesalazine has little effect on gene expression and its previous reported effect on fecal microbiota associated with much greater inflammation found in inflammatory bowel diseases is likely secondary to reduced inflammation. Increased expression of TLR4 and correlated receptors in IBS may mediate a general increase in sensitivity to external stimuli, particularly those that signal via the TLR system.

10.
Article in English | WPRIM (Western Pacific) | ID: wpr-900382

ABSTRACT

Background/Aims@#Diarrhea-predominant irritable bowel syndrome (IBS-D) has been previously associated with evidence of immune activation and altered microbiota. Our aim is to assess the effect of the anti-inflammatory agent, mesalazine, on inflammatory gene expression and microbiota composition in IBS-D. @*Methods@#We studied a subset of patients (n = 43) from a previously published 12-week radomized placebo-controlled trial of mesalazine. Mucosal biopsies were assessed by immunohistochemistry and reverse transcription-polymerase chain reaction for a range of markers of inflammation, altered permeability, and sensory receptors including Toll-like receptors (TLRs) at randomization after treatment. All biopsy data were compared to 21 healthy controls. Patient’s stool microbiota composition was analysed through 16S ribosomal RNA sequencing. @*Results@#We found no evidence of increased immune activation compared to healthy controls. However, we did find increased expression of receptors in both sensory pathways and innate immune response including TLR4. Higher TLR4 expression was associated with greater urgency. TLR4 expression correlated strongly with the expression of the receptors bradykinin receptor B2, chemerin chemokine-like receptor 1, and transient receptor potential cation channel, subfamily A, member 1 as well as TLR4’s downstream adaptor myeloid differentiation factor 88. Mesalazine had minimal effect on either gene expression or microbiota composition. @*Conclusions@#Biopsies from a well-characterized IBS-D cohort showed no substantial inflammation. Mesalazine has little effect on gene expression and its previous reported effect on fecal microbiota associated with much greater inflammation found in inflammatory bowel diseases is likely secondary to reduced inflammation. Increased expression of TLR4 and correlated receptors in IBS may mediate a general increase in sensitivity to external stimuli, particularly those that signal via the TLR system.

11.
Pediatr Investig ; 4(3): 168-177, 2020 Sep.
Article in English | MEDLINE | ID: mdl-33150310

ABSTRACT

IMPORTANCE: 131I-metaiodobenzylguanidine (131I-mIBG) has a significant targeted antitumor effect for neuroblastoma. However, currently there is a paucity of data for the use of 131I-mIBG as a "front-line" therapeutic agent in those patients with newly diagnosed high-risk neuroblastoma as part of the conditioning regimen for myeloablative chemotherapy (MAC). OBJECTIVE: To evaluate the feasibility of upfront consolidation treatment with 131I-mIBG plus MAC and hematopoietic stem cell transplantation (HSCT) in high-risk neuroblastoma patients. METHODS: A retrospective, single-center study was conducted from 2003-2019 on newly diagnosed high-risk neuroblastoma patients without progressive disease (PD) after the completion of induction therapy. They received 131I-mIBG infusion and MAC followed by HSCT. RESULTS: A total of 24 high-risk neuroblastoma patients were enrolled with a median age of 3.0 years at diagnosis. After receiving this sequential consolidation treatment, 3 of 13 patients who were in partial response (PR) before 131I-mIBG treatment achieved either complete response (CR) (n = 1) or very good partial response (VGPR) (n = 2) after HSCT. With a median follow-up duration of 13.0 months after 131I-mIBG therapy, the 5-year event-free survival and overall survival rates estimated were 29% and 38% for the entire cohort, and 53% and 67% for the patients who were in CR/VGPR at the time of 131I-mIBG treatment. INTERPRETATION: Upfront consolidation treatment with 131I-mIBG plus MAC and HSCT is feasible and tolerable in high-risk neuroblastoma patients, however the survival benefit of this 131I-mIBG regimen is only observed in the patients who were in CR/VGPR at the time of 131I-mIBG treatment.

12.
Soc Cogn Affect Neurosci ; 15(11): 1228-1237, 2020 12 17.
Article in English | MEDLINE | ID: mdl-33064803

ABSTRACT

We assessed the effect of a daytime sleep opportunity on planning and risk-related decision-making in emerging adults using multiple neurobehavioral assessments. A total of 136 healthy emerging adults (20.0 ± 1.5 years), 65% female, performed the Risky-Gains Task and the Tower of London test twice. Between these assessments, they were randomized to either have a sleep opportunity monitored by polysomnography (Sleep group, n = 101) or to stay awake (Wake group, n = 35). During Test 2, in comparison to the Sleep group, the Wake group showed increased sleepiness, worse planning ability and more decrease in reaction times when selecting risky choices. Changes in Tower of London test steps used and Risky-Gains Task response time correlated with the number of central and frontal fast sleep spindles, respectively. These results indicate that among emerging adults who commonly have poor sleep patterns, a daytime sleep opportunity was related to better planning ability, better psychomotor vigilance and stable response speeds in risk-related decision-making. Changes in planning and risk-related decision-making correlated with the number of sleep spindles during the nap, supporting a specific role for sleep in modulating planning and potentially other higher-order cognitive functions.


Subject(s)
Cognition/physiology , Sleep/physiology , Adolescent , Female , Humans , Male , Polysomnography/methods , Reaction Time/physiology , Risk-Taking , Wakefulness/physiology , Young Adult
13.
J Rehabil Med ; 52(5): jrm00062, 2020 05 29.
Article in English | MEDLINE | ID: mdl-32412645

ABSTRACT

OBJECTIVE: To identify the psychometric properties of the Long-Distance Corridor Walk (LDCW) among community-dwelling stroke survivors. DESIGN: Cross-sectional. SUBJECTS: Twenty-five stroke survivors and 25 healthy older adults. METHODS: The LDCW was administered to the 25 stroke survivors on 2 separate days with a 7-day interval. Fugl-Meyer Assessment for the Lower Extremities (FMA-LE), measurement of lower limb muscle strength, Berg Balance Scale (BBS), limit of stability (LOS), Narrow-Corridor Walk Test (NCWT), Timed Up and Go (TUG) test, and the Community Integration Measure-Cantonese version (CIM) were performed on either day. The healthy older adults completed the LDCW once, and the results were recorded by a random rater. RESULTS: The LDCW showed excellent inter-rater reliability and test-retest reliability, and significant correlations with FMA-LE, BBS, TUG, and NCWT. A cut-off score of 127.5 m for the 2-min walk and 426.69 s for the 400-m walk distinguished stroke survivors from healthy older adults. The MDC in the LDCW in the 2-min walk and 400-m walk were 18.69 m and 121.43 s, respectively. CONCLUSION: The LDCW is a reliable clinical measurement tool for the assessment of advanced walking capacity in stroke survivors.


Subject(s)
Stroke Rehabilitation/methods , Walking/physiology , Aged , Aged, 80 and over , Case-Control Studies , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Reproducibility of Results , Stroke Rehabilitation/mortality , Survivors
14.
ACS Appl Mater Interfaces ; 12(7): 8503-8512, 2020 Feb 19.
Article in English | MEDLINE | ID: mdl-32027479

ABSTRACT

Platinum(II) polypyridine complexes of a square-planar geometry have been used as spectroscopic reporters for quantification of various charged species through non-covalent metal-metal interactions. The characterization of molecular weights and architectures of polyelectrolytes represents a challenging task in polymer science. Here, we report the utilization of platinum(II) complex probes and non-covalent metal-metal interactions for sensing polyelectrolyte lengths and architectures. It is found that the platinum(II) probes can bind to linear polyelectrolytes via electrostatic attractions and give rise to significant spectroscopic changes associated with the formation of metal-metal interactions, and the extent of the spectroscopic changes is found to increase with the lengths of the linear polyelectrolytes. Besides, the platinum(II) probes have been found to co-assemble with the linear polyelectrolytes to form well-defined nanofibers, and the lengths of the linear polyelectrolytes can be directly estimated from the diameter of the nanofibers under transmission electron microscopy observation. Interestingly, upon mixing with the platinum(II) probes, polyelectrolytes with bottlebrush architectures have been found to exhibit larger spectroscopic changes than linear polyelectrolytes with the same chemical composition. Combined with the reported theoretical studies on counterion condensation of polyelectrolytes, the platinum(II) complexes are found to function as spectroscopic probes for sensing the charge densities of the polyelectrolytes with different lengths and diverse architectures. Moreover, platinum(II) probes pre-organized in nanostructured aggregates have been found to intercalate into double-stranded DNA, which are naturally occurring biological polyelectrolytes with helical architectures and intercalation sites, to give significant enhancement of spectroscopic changes when compared to the intercalation of monomeric platinum(II) probes into double-stranded DNA.


Subject(s)
DNA/chemistry , Intercalating Agents/chemistry , Nanofibers/chemistry , Platinum/chemistry , Polyelectrolytes/chemistry , Acrylic Resins/chemistry , Microscopy, Electron, Transmission , Molecular Structure , Nanofibers/ultrastructure , Nanostructures/chemistry , Nanostructures/ultrastructure , Polyethylene Glycols/chemistry , Polymers/chemistry , Spectrum Analysis , Static Electricity
15.
J Pharm Biomed Anal ; 179: 113009, 2020 Feb 05.
Article in English | MEDLINE | ID: mdl-31816475

ABSTRACT

Poria cocos (Schw.) Wolf has been widely used in traditional Chinese medicine (TCM) for centuries. Its three medicinal parts are Poria Cutis, the epidermis or fulingpi in Chinese; White Poria, the middle part or baifuling; and Poria cum Radix Pini, the sclerotium with some part of host pine root or fushen. The hostwood in fushen is the inner part, known as fushenmu. The epidermis, middle part and middle-plus-inner part have different clinical applications, but the differences in their chemistry have not been well determined. Previous studies only concentrated on the differences in secondary metabolites in different parts of P. cocos; however, in this study, we focused on the carbohydrates, another major type of bioactive chemicals in P. cocos, which is also different from most of the other TCM researches. The carbohydrates (polysaccharides, oligosaccharides and monosaccharides) in three parts (epidermis, middle and inner part) of P. cocos were qualitatively and quantitatively characterized by high performance gel permeation chromatography coupled with charged aerosol detector (HPGPC-CAD) and ultra-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC-QqQ-MS/MS). The obtained data were further processed by principal component analysis (PCA) and supervised orthogonal partial least squared discriminant analysis (OPLS-DA). The results showed that the epidermis contained more polysaccharides with larger molecular weight and higher amount of glucose residue than that of the middle and inner parts, indicating the epidermis as the key site of accumulation of P. cocos polysaccharides. When compared with the epidermis and inner part, the middle part contained the highest glucose molar ratio greater than 92 % in the three types of carbohydrates, whereas the inner part possessed the greatest molar ratio of mannose, xylose, arabinose, rhamnose, glucuronic acid, and galacturonic acid in all kinds of carbohydrates. Furthermore, PCA and OPLS-DA clearly demonstrated that arabinose, glucose, galacturonic acid, and ribose played key roles in the clusters between the epidermis, middle and inner parts. The observed differences in the chemical components in the three parts could provide some explanation for the discriminative clinical applications of Poria Cutis, White Poria, and Poria cum Radix Pini. These findings also provided a chemical basis for quality assessment of P. cocos.


Subject(s)
Carbohydrates/isolation & purification , Wolfiporia/chemistry , Carbohydrates/analysis , Carbohydrates/chemistry , Chromatography, Gel/methods , Chromatography, High Pressure Liquid/methods , Molecular Weight , Principal Component Analysis , Tandem Mass Spectrometry/methods
16.
J Am Chem Soc ; 141(46): 18570-18577, 2019 11 20.
Article in English | MEDLINE | ID: mdl-31709796

ABSTRACT

Amyloid fibrillation has been acknowledged as a hallmark of a number of neurodegenerative ailments such as Alzheimer's disease. Accordingly, efficient detection of amyloid fibrillation will allow for great advances in the field of biomedical applications as well as in achieving early medical diagnosis. In this work, a luminescence assay for the sensitive and specific detection of amyloid fibrillation was developed by using platinum(II) complexes as sensing platforms. Supramolecular self-assembly of platinum(II) complexes was induced upon addition of amyloid, leading to alterations in the spectroscopic and luminescence properties of the complexes. As compared to fluorescent dyes, luminescent platinum(II) complexes exhibit attractive large Stokes shifts, phosphorescence lifetimes in the microsecond to submicrosecond regime, and low-energy red emission after aggregation, which are advantageous to biological imaging. At the same time, the platinum(II) complex adopted herein was found to have high photostability, high selectivity and specificity, and low cytotoxicity. The proposed design is the very first approach to detect amyloid fibrillation through the supramolecular self-assembly of luminescent platinum(II) complexes.


Subject(s)
Amyloid/analysis , Coordination Complexes/chemistry , Insulin/analysis , Luminescent Agents/chemistry , Platinum/chemistry , Amyloid/ultrastructure , Animals , Cattle , Luminescent Measurements , Microscopy, Confocal , Solubility , Water/chemistry
17.
J Environ Manage ; 248: 109302, 2019 Oct 15.
Article in English | MEDLINE | ID: mdl-31377539

ABSTRACT

Palm oil sludge (POS) is an organic waste generated from the palm oil industry. POS causes environmental pollution if it is improperly disposed. In this study, the potential of activated POS biochar, as an adsorbent for the removal of SO2 gas was tested. POS biochar was physically activated using CO2 gas. The effects of activation preparation variables i.e. activation temperature (300-700 °C), activation time (30-150 min) and CO2 flow rate (100-500 ml/min) were investigated using design expert version 8.0.7.1 software. Central Composite Design (CCD) was used to develop a quadratic model to correlate the operating variables with the activated biochar adsorption capacity. Analysis of variance (ANOVA) was performed to identify the significant factors on the experimental design response. The optimum preparation conditions of activated POS biochar were found to be at activation temperature of 442 °C, activation time of 63 min and CO2 flow rate of 397 ml/min. The maximum adsorption capacity at the optimum conditions was recorded as 16.65 mg/g. The adsorption capacity increased significantly after the activation process. Characteristics of the activated POS biochar proposed that SO2 was physically adsorbed. Furthermore, it was found that the adsorption capacity can be further enhanced by increasing the reaction temperature to 100 °C or with 15% of relative humidity in the inlet gas. The prepared adsorbents can be regenerated by thermal treatment.


Subject(s)
Sewage , Sulfur Dioxide , Adsorption , Charcoal , Palm Oil
18.
J Environ Manage ; 237: 281-288, 2019 May 01.
Article in English | MEDLINE | ID: mdl-30802752

ABSTRACT

In this work, the influence of pyrolysis temperature on the physicochemical properties of palm oil mill sludge biochar (POSB) and its adsorption properties towards cadmium (Cd) and copper (Cu) was investigated. Characterization experiments suggested that POSBs' surface functional groups play the major role in the adsorption process. POSB pyrolyzed at 400 °C showed the best characteristics for Cu and Cd removal. Adsorption study indicated that contact time and shaking speed enhances the adsorption capacity of POSB. It was affirmed that pH adjustment is not necessary for POSB to adsorb Cu and Cd. Mechanism studies fitted well with Langmuir and Pseudo-Second Order model. Thermodynamic parameters indicated that the adsorption was spontaneous, endothermic and correspond to chemical adsorption. The highest uptakes of Cu and Cd were recorded at 48.8 mg/g and 46.2 mg/g respectively. This work verifies that the temperature used for palm oil mill sludge (POS) pyrolysis and adsorption condition played the most prominent role in Cu and Cd removal from aqueous solutions.


Subject(s)
Cadmium , Water Pollutants, Chemical , Adsorption , Charcoal , Copper , Kinetics , Palm Oil , Sewage , Temperature
19.
ACS Appl Mater Interfaces ; 11(5): 4799-4808, 2019 Feb 06.
Article in English | MEDLINE | ID: mdl-30694047

ABSTRACT

A new approach toward acetylcholinesterase (AChE) detection has been demonstrated based on the electrostatic interactions between anionic alkynylplatinum(II) complex molecules and cationic coordination polymer, together with the spectroscopic and emission characteristics of alkynylplatinum(II) complexes upon supramolecular self-assembly. This process involves strengthening of distinct noncovalent Pt(II)···Pt(II) and π-π stacking interactions, which is evidenced by UV-vis absorption, emission, and resonance light scattering results. Such a method has been applied to AChE inhibitor screening, which is important as the demand for AChE inhibitor assays arises along with the drug development for Alzheimer's disease. It affords an emission turn-on response and operates in a continuous and label-free fashion. The low-energy red emission and large Stokes shift of alkynylplatinum(II) complexes are advantageous to biological applications.


Subject(s)
Acetylcholinesterase , Drug Discovery/methods , Luminescent Measurements/methods , Organoplatinum Compounds/chemistry , Acetylcholinesterase/analysis , Acetylcholinesterase/metabolism , Animals , Biosensing Techniques/methods , Cholinesterase Inhibitors/analysis , Cholinesterase Inhibitors/metabolism , Humans , Polymers/chemistry
20.
J Am Chem Soc ; 140(30): 9594-9605, 2018 08 01.
Article in English | MEDLINE | ID: mdl-30040413

ABSTRACT

Establishment of energy landscape has emerged as an efficient pathway for improved understanding and manipulation of both thermodynamic and kinetic behaviors of complicated supramolecular systems. Herein, we report the establishment of energy landscapes of supramolecular coassembly of platinum(II) complexes and polymers, as well as the fabrication of nanostructures with enhanced complexity and intriguing properties from the coassembly systems. In the energy landscape, coassembly at room temperature has been found to only allow the longitudinal growth of platinum(II) complexes and block copolymers into core-shell nanofibers that are the kinetically trapped products. Thermal annealing can switch on the transverse growth of platinum(II) complexes and block copolymers to produce core-shell nanobelts that are the thermodynamically stable nanostructures. The extents of the transverse growth are found to increase with thermal annealing temperatures, leading to nanobelts with larger widths. Besides, rapid quenching of a hot coassembly mixture to room temperature can capture intermediate nanobelt- block-nanofiber nanostructures that are metastable and capable of converting to nanobelts upon further incubation at room temperature. Moreover, sonication treatment has been found to couple with the energy landscape of the coassembly system and open a unique energy-driven pathway to activate the kinetically forbidden nanofiber-to-nanobelt morphological transformation. Furthermore, based on the established energy landscapes, nanosphere- block-nanobelt nanostructures with distinct segmented architectures have been fabricated by thermal annealing of the ternary mixture of platinum(II) complexes, block copolymers, and polymer brushes in a one-pot and single-step procedure. Finally, the nanobelts and nanosphere- block-nanobelt nanostructures are found to possess intriguing morphological stability against acid and dilution, exhibiting characteristics that are important for promising biomedical applications.

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