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1.
Cell ; 152(1-2): 68-81, 2013 Jan 17.
Article in English | MEDLINE | ID: mdl-23332747

ABSTRACT

The majority of riboswitches are regulatory RNAs that regulate gene expression by binding small-molecule metabolites. Here we report the discovery of an aminoglycoside-binding riboswitch that is widely distributed among antibiotic-resistant bacterial pathogens. This riboswitch is present in the leader RNA of the resistance genes that encode the aminoglycoside acetyl transferase (AAC) and aminoglycoside adenyl transferase (AAD) enzymes that confer resistance to aminoglycoside antibiotics through modification of the drugs. We show that expression of the AAC and AAD resistance genes is regulated by aminoglycoside binding to a secondary structure in their 5' leader RNA. Reporter gene expression, direct measurements of drug RNA binding, chemical probing, and UV crosslinking combined with mutational analysis demonstrate that the leader RNA functions as an aminoglycoside-sensing riboswitch in which drug binding to the leader RNA leads to the induction of aminoglycosides antibiotic resistance.


Subject(s)
Aminoglycosides/pharmacology , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Bacteria/genetics , RNA, Bacterial/metabolism , Riboswitch , 5' Untranslated Regions , Acetyltransferases/genetics , Acinetobacter baumannii/genetics , Base Sequence , Escherichia coli , Methyltransferases/genetics , Molecular Sequence Data , Nucleic Acid Conformation , Nucleotidyltransferases/genetics , RNA, Bacterial/chemistry , RNA, Bacterial/genetics
2.
Proc Natl Acad Sci U S A ; 121(28): e2322972121, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38968116

ABSTRACT

Rapid accumulation of repair factors at DNA double-strand breaks (DSBs) is essential for DSB repair. Several factors involved in DSB repair have been found undergoing liquid-liquid phase separation (LLPS) at DSB sites to facilitate DNA repair. RNF168, a RING-type E3 ubiquitin ligase, catalyzes H2A.X ubiquitination for recruiting DNA repair factors. Yet, whether RNF168 undergoes LLPS at DSB sites remains unclear. Here, we identified K63-linked polyubiquitin-triggered RNF168 condensation which further promoted RNF168-mediated DSB repair. RNF168 formed liquid-like condensates upon irradiation in the nucleus while purified RNF168 protein also condensed in vitro. An intrinsically disordered region containing amino acids 460-550 was identified as the essential domain for RNF168 condensation. Interestingly, LLPS of RNF168 was significantly enhanced by K63-linked polyubiquitin chains, and LLPS largely enhanced the RNF168-mediated H2A.X ubiquitination, suggesting a positive feedback loop to facilitate RNF168 rapid accumulation and its catalytic activity. Functionally, LLPS deficiency of RNF168 resulted in delayed recruitment of 53BP1 and BRCA1 and subsequent impairment in DSB repair. Taken together, our finding demonstrates the pivotal effect of LLPS in RNF168-mediated DSB repair.


Subject(s)
DNA Breaks, Double-Stranded , DNA Repair , Tumor Suppressor p53-Binding Protein 1 , Ubiquitin-Protein Ligases , Ubiquitination , Ubiquitin-Protein Ligases/metabolism , Ubiquitin-Protein Ligases/genetics , Humans , Tumor Suppressor p53-Binding Protein 1/metabolism , Tumor Suppressor p53-Binding Protein 1/genetics , Ubiquitin/metabolism , Histones/metabolism , Histones/genetics , Polyubiquitin/metabolism
3.
PLoS Pathog ; 18(7): e1010615, 2022 07.
Article in English | MEDLINE | ID: mdl-35816546

ABSTRACT

Tuberculosis (TB) is one of the leading infectious diseases of global concern, and one quarter of the world's population are TB carriers. Biotin metabolism appears to be an attractive anti-TB drug target. However, the first-stage of mycobacterial biotin synthesis is fragmentarily understood. Here we report that three evolutionarily-distinct BioH isoenzymes (BioH1 to BioH3) are programmed in biotin synthesis of Mycobacterium smegmatis. Expression of an individual bioH isoform is sufficient to allow the growth of an Escherichia coli ΔbioH mutant on the non-permissive condition lacking biotin. The enzymatic activity in vitro combined with biotin bioassay in vivo reveals that BioH2 and BioH3 are capable of removing methyl moiety from pimeloyl-ACP methyl ester to give pimeloyl-ACP, a cognate precursor for biotin synthesis. In particular, we determine the crystal structure of dimeric BioH3 at 2.27Å, featuring a unique lid domain. Apart from its catalytic triad, we also dissect the substrate recognition of BioH3 by pimeloyl-ACP methyl ester. The removal of triple bioH isoforms (ΔbioH1/2/3) renders M. smegmatis biotin auxotrophic. Along with the newly-identified Tam/BioC, the discovery of three unusual BioH isoforms defines an atypical 'BioC-BioH(3)' paradigm for the first-stage of mycobacterial biotin synthesis. This study solves a long-standing puzzle in mycobacterial nutritional immunity, providing an alternative anti-TB drug target.


Subject(s)
Antitubercular Agents , Biotin , Biotin/chemistry , Biotin/metabolism , Escherichia coli/metabolism , Esters/metabolism , Isoenzymes/metabolism
4.
Chemistry ; : e202401693, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38837262

ABSTRACT

The serious dendrite growth and H2O-induced side reactions on the Zn electrode lead to a significant fading in the cycling performance, hindering the development of commercial applications of aqueous Zn-ion batteries (AZIBs). Herein, a novel bifunctional network coating of dynamically cross-linking sodium alginate with trehalose has been rationally constructed on the Zn anode (Zn@AT). Firstly, the AT coating possesses abundant zinophilic oxygen-containing functional groups, which are able to induce uniform Zn2+ ion flux. Secondly, the AT coating as a solid barrier can effectively inhibit H2O-induced side reactions by lowering the activity of H2O molecules. More specially, based on the dynamic cross-linking, AT network coating is endowed with self-healing capacity during cycling for durable battery operation. Consequentially, Zn@AT anodes in symmetric cells can cycle stably for 2787 h at 2 mA cm-2/2 mAh cm-2, and even achieve a significantly long cycle performance of 1087 h at large charge/discharge depths of 10 mA cm-2/10 mAh cm-2. Moreover, the Zn@AT//MnO2 full cell shows excellent specific capacity of 175 mAh g-1 after 400 cycles. This study lights an effective strategy to enhance the durability of Zn electrodes in AZIBs.

5.
Liver Int ; 44(1): 202-213, 2024 01.
Article in English | MEDLINE | ID: mdl-37904633

ABSTRACT

BACKGROUND AND AIMS: Diagnosis of metabolic dysfunction-associated steatohepatitis (MASH) requires histology. In this study, a magnetic resonance imaging (MRI) score was developed and validated to identify MASH in patients with metabolic dysfunction-associated steatotic liver disease (MASLD). Secondarily, a screening strategy for MASH diagnosis was investigated. METHODS: This prospective multicentre study included 317 patients with biopsy-proven MASLD and contemporaneous MRI. The discovery cohort (Spain, Portugal) included 194 patients. NAFLD activity score (NAS) and fibrosis were assessed with the NASH-CRN histologic system. MASH was defined by the presence of steatosis, lobular inflammation, and ballooning, with NAS ≥4 with or without fibrosis. An MRI-based composite biomarker of Proton Density Fat Fraction and waist circumference (MR-MASH score) was developed. Findings were afterwards validated in an independent cohort (United States, Spain) with different MRI protocols. RESULTS: In the derivation cohort, 51% (n = 99) had MASH. The MR-MASH score identified MASH with an AUC = .88 (95% CI .83-.93) and strongly correlated with NAS (r = .69). The MRI score lower cut-off corresponded to 88% sensitivity with 86% NPV, while the upper cut-off corresponded to 92% specificity with 87% PPV. MR-MASH was validated with an AUC = .86 (95% CI .77-.92), 91% sensitivity (lower cut-off) and 87% specificity (upper cut-off). A two-step screening strategy with sequential MR-MASH examination performed in patients with indeterminate-high FIB-4 or transient elastography showed an 83-84% PPV to identify MASH. The AUC of MR-MASH was significantly higher than that of the FAST score (p < .001). CONCLUSIONS: The MR-MASH score has clinical utility in the identification and management of patients with MASH at risk of progression.


Subject(s)
Liver , Non-alcoholic Fatty Liver Disease , Humans , Liver/pathology , Non-alcoholic Fatty Liver Disease/complications , Non-alcoholic Fatty Liver Disease/diagnostic imaging , Prospective Studies , Magnetic Resonance Imaging , Fibrosis , Biopsy , Biomarkers/metabolism , Liver Cirrhosis/diagnostic imaging , Liver Cirrhosis/metabolism
6.
Phys Chem Chem Phys ; 26(5): 4052-4061, 2024 Jan 31.
Article in English | MEDLINE | ID: mdl-38224136

ABSTRACT

Nanomoduling the 3D shape and chemical functionalities in a synthetic polymer may create recognition cavities for biomacromolecule binding, which serves as an attractive alternative to natural antibodies with much less cost. To obtain fundamental understanding and predict molecular design rules of the polymer antibody, we analyze the complex structure between the biomarker protein epithelial cell adhesion molecule (EpCAM) and a series of polymer ligands via molecular dynamics (MD) simulations. For monomeric ligands, strong enrichment of aromatic residues in protein binding sites is revealed, in line with the reported observations for natural antibodies. Yet, for linear polymers with a growing degree of polymerization, for the first time, a drastic change is revealed on the type of enriched protein residues and the location of protein binding sites, driven by the increasing steric hindrance effect that makes the adsorption of the polymer in the protein exterior feasible. Varying the polymer length and monomeric composition also significantly affects the ligand binding affinity. Here, we have captured three distinct dependences of the ligand binding free energy on the degree of polymerization: for NIPAm based hydrophilic polymers, TBAm dominated hydrophobic polymers and AAc dominated charged polymers. These results can be rationalized by the complex structure and the composition of protein residues at the binding interface. The entire analysis demonstrates unique binding features for polymer ligands and the possibility to modulate their binding sites and affinity by engineering the polymer structure.


Subject(s)
Polymers , Proteins , Polymers/chemistry , Ligands , Proteins/chemistry , Binding Sites , Adsorption
7.
Proc Natl Acad Sci U S A ; 118(46)2021 11 16.
Article in English | MEDLINE | ID: mdl-34772807

ABSTRACT

Chronic infection with liver flukes (such as Clonorchis sinensis) can induce severe biliary injuries, which can cause cholangitis, biliary fibrosis, and even cholangiocarcinoma. The release of extracellular vesicles by C. sinensis (CsEVs) is of importance in the long-distance communication between the hosts and worms. However, the biological effects of EVs from liver fluke on biliary injuries and the underlying molecular mechanisms remain poorly characterized. In the present study, we found that CsEVs induced M1-like activation. In addition, the mice that were administrated with CsEVs showed severe biliary injuries associated with remarkable activation of M1-like macrophages. We further characterized the signatures of miRNAs packaged in CsEVs and identified a miRNA Csi-let-7a-5p, which was highly enriched. Further study showed that Csi-let-7a-5p facilitated the activation of M1-like macrophages by targeting Socs1 and Clec7a; however, CsEVs with silencing Csi-let-7a-5p showed a decrease in proinflammatory responses and biliary injuries, which involved in the Socs1- and Clec7a-regulated NF-κB signaling pathway. Our study demonstrates that Csi-let-7a-5p delivered by CsEVs plays a critical role in the activation of M1-like macrophages and contributes to the biliary injuries by targeting the Socs1- and Clec7a-mediated NF-κB signaling pathway, which indicates a mechanism contributing to biliary injuries caused by fluke infection. However, molecules other than Csi-let-7a-5p from CsEVs that may also promote M1-like polarization and exacerbate biliary injuries are not excluded.


Subject(s)
Extracellular Vesicles/metabolism , Fasciola hepatica/metabolism , Macrophages/metabolism , Animals , Mice , Mice, Inbred C57BL , MicroRNAs/metabolism , NF-kappa B/metabolism , Persistent Infection/parasitology , Signal Transduction/physiology
8.
J Asian Nat Prod Res ; 26(6): 765-771, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38373226

ABSTRACT

To clarify the chemical basis of the total alkaloids of Uncaria rhynchophylla, HPLC-VWD chromatogram of total alkaloids was established. Under its guidance, modern chromatographic and spectroscopic techniques were used to track, isolate and identify the representative principal components. As a result, one new monoterpenoid indole alkaloid, 3S,15S-N4-methoxymethyl-geissoschizine methyl ether (1), together with 20 known alkaloids (2-21), and 5 other known compounds (22-26) were obtained. Meanwhile, sixteen characteristic peaks were identified from the total alkaloids using HPLC analysis. Then, the anti-neuroinflammatory effect of compounds 1-21 was assessed through inhibiting nitric ---oxide (NO) production in lipopolysaccharide (LPS)-induced BV-2 microglial cells. Among them, compounds 1, 3, 7, 8, 11, 12, 19 and 21 showed potent inhibitory activities with IC50 values of 5.87-76.78 µM.


Subject(s)
Alkaloids , Anti-Inflammatory Agents , Indole Alkaloids , Lipopolysaccharides , Microglia , Nitric Oxide , Uncaria , Uncaria/chemistry , Molecular Structure , Alkaloids/pharmacology , Alkaloids/chemistry , Nitric Oxide/antagonists & inhibitors , Nitric Oxide/biosynthesis , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/chemistry , Lipopolysaccharides/pharmacology , Microglia/drug effects , Animals , Mice , Chromatography, High Pressure Liquid , Secologanin Tryptamine Alkaloids/pharmacology , Secologanin Tryptamine Alkaloids/chemistry
9.
J Hepatol ; 79(3): 592-604, 2023 09.
Article in English | MEDLINE | ID: mdl-37121437

ABSTRACT

BACKGROUND & AIMS: We conducted an individual patient data meta-analysis to establish stiffness cut-off values for magnetic resonance elastography (MRE) in staging liver fibrosis and to assess potential confounding factors. METHODS: A systematic review of the literature identified studies reporting MRE data in patients with NAFLD. Data were obtained from the corresponding authors. The pooled diagnostic cut-off value for the various fibrosis stages was determined in a two-stage meta-analysis. Multilevel modelling methods were used to analyse potential confounding factors influencing the diagnostic accuracy of MRE in staging liver fibrosis. RESULTS: Eight independent cohorts comprising 798 patients were included in the meta-analysis. The area under the receiver operating characteristic curve (AUROC) for MRE in detecting significant fibrosis was 0.92 (sensitivity, 79%; specificity, 89%). For advanced fibrosis, the AUROC was 0.92 (sensitivity, 87%; specificity, 88%). For cirrhosis, the AUROC was 0.94 (sensitivity, 88%, specificity, 89%). Cut-offs were defined to explore concordance between MRE and histopathology: ≥F2, 3.14 kPa (pretest probability, 39.4%); ≥F3, 3.53 kPa (pretest probability, 24.1%); and F4, 4.45 kPa (pretest probability, 8.7%). In generalized linear mixed model analysis, histological steatohepatitis with higher inflammatory activity (odds ratio 2.448, 95% CI 1.180-5.079, p <0.05) and high gamma-glutamyl transferase (GGT) concentration (>120U/L) (odds ratio 3.388, 95% CI 1.577-7.278, p <0.01] were significantly associated with elevated liver stiffness, and thus affecting accuracy in staging early fibrosis (F0-F1). Steatosis, as measured by magnetic resonance imaging proton density fat fraction, and body mass index(BMI) were not confounders. CONCLUSIONS: MRE has excellent diagnostic performance for significant, advanced fibrosis and cirrhosis in patients with NAFLD. Elevated inflammatory activity and GGT level may lead to overestimation of early liver fibrosis, but anthropometric measures such as BMI or the degree of steatosis do not. IMPACT AND IMPLICATIONS: This individual patient data meta-analysis of eight international cohorts, including 798 patients, demonstrated that MRE achieves excellent diagnostic accuracy for significant, advanced fibrosis and cirrhosis in patients with NAFLD. Cut-off values (significant fibrosis, 3.14 kPa; advanced fibrosis, 3.53 kPa; and cirrhosis, 4.45 kPa) were established. Elevated inflammatory activity and gamma-glutamyltransferase level may affect the diagnostic accuracy of MRE, leading to overestimation of liver fibrosis in early stages. We observed no impact of diabetes, obesity, or any other metabolic disorder on the diagnostic accuracy of MRE.


Subject(s)
Elasticity Imaging Techniques , Non-alcoholic Fatty Liver Disease , Humans , Non-alcoholic Fatty Liver Disease/diagnosis , Non-alcoholic Fatty Liver Disease/diagnostic imaging , Elasticity Imaging Techniques/methods , Liver Cirrhosis/diagnostic imaging , Liver Cirrhosis/etiology , Fibrosis , ROC Curve , Magnetic Resonance Imaging/methods , Liver/diagnostic imaging , Liver/pathology
10.
Mol Ecol ; 32(11): 2884-2897, 2023 06.
Article in English | MEDLINE | ID: mdl-36811404

ABSTRACT

Many animals, including insects, exhibit plasticity of body colour in response to environmental changes. Varied expression of carotenoids, major cuticle pigments, significantly contributes to body colour flexibility. However, the molecular mechanisms by which environmental cues regulate carotenoid expression remain largely unknown. In this study, we used the ladybird Harmonia axyridis as a model to investigate the photoperiodic-responsive plasticity of elytra coloration and its endocrine regulation. It was found that H. axyridis females under long-day conditions develop elytra that are much redder than those under short-day conditions, resulting from the differential accumulation of carotenoids. Exogenous hormone application and RNAi-mediated gene knockdown indicate that carotenoid deposition was directed through the juvenile hormone (JH) receptor-mediated canonical pathway. Moreover, we characterized an SR-BI/CD36 (SCRB) gene SCRB10 as the carotenoid transporter responding to JH signalling and regulating the elytra coloration plasticity. Taken together, we propose that JH signalling transcriptionally regulates the carotenoid transporter gene for the photoperiodic coloration plasticity of elytra in the beetles, which reveals a novel role of the endocrine system in the regulation of carotenoid-associated animal body coloration under environmental stimuli.


Subject(s)
Coleoptera , Animals , Female , Coleoptera/genetics , Pigmentation/genetics , Carotenoids , RNA Interference
11.
Opt Express ; 31(20): 33548-33564, 2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37859134

ABSTRACT

The escalating need for expansive data bandwidth, and the resulting capacity constraints of the single mode fiber (SMF) have positioned the 2-µm waveband as a prospective window for emerging applications in optical communication. This has initiated an ecosystem of silicon photonic components in the region driven by CMOS compatibility, low cost, high efficiency and potential for large-scale integration. In this study, we demonstrate a plasma dispersive 4 × 4 photonic switch operating at the 2-µm waveband with the highest switching speed. The demonstrated switch operates across a 45-nm bandwidth, with 10-90% rise and 90-10% fall time of 1.78 ns and 3.02 ns respectively. In a 4 × 4 implementation, crosstalk below -15 dB and power consumption lower than 19.15 mW across all 16 optical paths are indicated. This result brings high-speed optical switching to the portfolio of devices at the promising waveband.

12.
Eur J Clin Microbiol Infect Dis ; 42(1): 23-31, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36322255

ABSTRACT

Carbapenem-resistant Klebsiella pneumoniae are distributed worldwide. This study aimed to characterize a hypervirulent tigecycline-resistant and carbapenem-resistant Klebsiella pneumoniae strain, XJ-K2, collected from a patient's blood. We tested antimicrobial susceptibility, virulence, and whole-genome sequencing (WGS) on strain XJ-K2. WGS data were used to identify virulence and resistance genes and to perform multilocus sequence typing (MLST) and phylogenetic analysis. Three novel plasmids, including a pLVPK-like virulence plasmid (pXJ-K2-p1) and two multiple resistance plasmids (pXJ-K2-KPC-2 and pXJ-K2-p3), were discovered in strain XJ-K2. The IncFII(pCRY) plasmid pXJ-K2-p3 carried the dfrA14, sul2, qnrS1, blaLAP-2, and tet(A) resistance genes. The IncFII(pHN7A8)/IncR plasmid pXJ-K2-KPC-2 also carried a range of resistance elements, containing rmtB, blaKPC-2, blaTEM-1, blaCTX-M-65, and fosA3. MLST analysis revealed that strain XJ-K2 belonged to sequence type 11 (ST11). Seven complete phage sequences and many virulence genes were found in strain XJ-K2. Meanwhile, antimicrobial susceptibility tests and G. mellonella larval infection models confirmed the extensively drug resistance (XDR) and hypervirulence of KJ-K2. To our knowledge, this is the first observation and description of the ST11 hypervirulent tigecycline- and carbapenem-resistant K. pneumoniae strain co-carrying blaKPC-2 and the tet(A) in a patient's blood in China. Further investigation is needed to understand the resistance and virulence mechanisms of this significant hypervirulent tigecycline- and carbapenem-resistant strain.


Subject(s)
Carbapenem-Resistant Enterobacteriaceae , Klebsiella Infections , Humans , Tigecycline/pharmacology , Klebsiella pneumoniae , Anti-Bacterial Agents/pharmacology , Klebsiella Infections/epidemiology , Klebsiella Infections/microbiology , Multilocus Sequence Typing , Phylogeny , beta-Lactamases/genetics , Carbapenems/pharmacology , Plasmids/genetics , Carbapenem-Resistant Enterobacteriaceae/genetics
14.
Behav Sleep Med ; 21(6): 774-786, 2023 11 02.
Article in English | MEDLINE | ID: mdl-36594607

ABSTRACT

OBJECTIVES: To quantify school-age children's sleep and parent-associated factors on weekdays and weekends in Singapore, and investigate school-related and parent-related factors associated with short sleep. METHODS: In an online survey, 251 parents with a child aged 7-12 y in Singapore reported their child's sleep duration and school start time. Parent-related factors including sleep hygiene (e.g., parent-set bedtime), sleep priority (the amount of sleep respondents allowed their children to trade for other activities), and both parents' sleep durations, were also reported. RESULTS: The prevalence of short sleep among the children was 64.5% on weekdays and 19.5% on weekends. Children's sleep duration increased from 8.42 h on weekdays to 9.45 h on weekends (p < .001). Relative to weekdays, on weekends, parents showed similar increases in sleep durations (p < .001), imposed poorer sleep hygiene on their children (reduced likelihood of setting bedtimes and increased pre-bedtime electronic device use; p < .001), and allowed their children to trade more sleep for interacting with family and friends, social media, gaming, and TV / videos (p < .001). Shorter sleep duration in children was significantly associated with earlier school start time (B = 0.80, p = .02) and poorer sleep hygiene on weekdays (B = 0.16, p < .001), but lower sleep priority (B = 0.05, p = .002) and shorter parental sleep duration on weekends (maternal: B = 0.18, p < .001, paternal: B = 0.17, p = .002). CONCLUSIONS: Delaying school start times may be effective in increasing school-age children's sleep duration on weekdays, while family-based interventions designed to enhance sleep hygiene, priority of sleep over other activities, and parents' sleep durations can benefit children's sleep duration on both weekdays and weekends.


Subject(s)
Sleep Duration , Sleep Wake Disorders , Humans , Child , Sleep , Time Factors , Parents , Surveys and Questionnaires
15.
Childs Nerv Syst ; 39(12): 3445-3455, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37284980

ABSTRACT

PURPOSE: Cerebrospinal fluid (CSF) shunt failures in children are devastating. The primary aims of this study are to, firstly, review our institutional series of ventriculoperitoneal shunt (VPS) insertions and identify factors associated with shunt failure. METHODS: This is a single-institution, retrospective study conducted over a 12-year period. All patients under 18 years old with VPS inserted were included. Variables of interest such as patient characteristics, hydrocephalus aetiology, shunt implant details, and outcomes were subjected to statistical analyses. RESULTS: A total of 214 VPS patients were selected for this study. The mean age at VPS insertion was 6 months with a mean follow-up duration of 44 months. The most common type of hydrocephalus was obstructive (n = 142, 66.4%), and the most frequent aetiology was tumour-related (n = 66, 30.8%). The 30-day shunt failure rate was 9.3%: 9 infections (4.2%), 7 occlusions (3.3%), and 4 others (1.9%). After multivariable analysis, only recent central nervous system (CNS) infection prior to VPS insertion remained significant (OR 15.4 (1.3-175), p = 0.028). CONCLUSION: This is the first, large-scale local study focused on the shunt failure in Singaporean children. Significant findings in our study demonstrate that recently treated CNS infection is a factor associated with 30-day shunt failure while the values of CSF constituents were not contributory.


Subject(s)
Hydrocephalus , Ventriculoperitoneal Shunt , Child , Humans , Adolescent , Infant , Ventriculoperitoneal Shunt/adverse effects , Retrospective Studies , Singapore/epidemiology , Hydrocephalus/surgery , Hydrocephalus/etiology , Hospitals
16.
Ophthalmic Res ; 66(1): 1406-1416, 2023.
Article in English | MEDLINE | ID: mdl-37926084

ABSTRACT

INTRODUCTION: The primary aim of this study was to assess the longitudinal changes in retinal nerve fiber layer (RNFL) thickness and relative ONH parameters using spectral-domain optical coherence tomography (SD-OCT) in the living eyes of nonhuman primates with spontaneous glaucoma. METHODS: Totally 9 macaque subjects underwent a standard fundus photo and OCT examination, including 3 adult monkeys with stable elevated intraocular pressure (IOP) as the glaucoma suspect group and 6 normal IOP monkeys as the control group. Each eye of primates with IOP measurement was repeated three times. OCT measurements recorded RNFL, Bruch's membrane opening (BMO) minimum rim width (MRW). The follow-up scan of glaucomatous subjects was undergone in 10 months. RESULTS: The mean ages of glaucoma and healthy subjects are 19.33 ± 0.33 and 20.5 ± 1.46 years. Elevated IOP was achieved in three nonhuman primate eyes with an average increase of 10 mm Hg over the study period. Elevated IOP was associated with decreased RNFL thickness in all the regions and decreased RNFL phase retardation in the superior and inferior regions. When averaged over the entire retinal area, only the whole RNFL and temporal regions showed a significant decrease. The mean IPL thicknesses are 87.17 ± 2.15 µm in glaucomatous and 93.33 ± 1.51 µm in healthy eyes (p = 0.03). Lamina cribrosa parameters are measured from the OCT images and showed significant differences between glaucoma primates and normal primates. CONCLUSIONS: Of the measured parameters, decreased RNFL and MRW were correlated with glaucomatous damage. Natural glaucoma primate can be a natural glaucoma model which is closer to glaucoma in humans.


Subject(s)
Glaucoma , Ocular Hypertension , Optic Disk , Adult , Animals , Humans , Adolescent , Young Adult , Intraocular Pressure , Retinal Ganglion Cells , Glaucoma/diagnosis , Ocular Hypertension/diagnosis , Tomography, Optical Coherence/methods , Primates
17.
Acta Neurochir (Wien) ; 165(12): 3805-3813, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37770798

ABSTRACT

PURPOSE: Despite significant advances, the literature on the optimal surgical treatment for spontaneous supratentorial intracerebral haematoma (ICH) remains lacking. Intraoperative ICP measured on closure (closure ICP) was reported to be a potential marker of adequate decompression in various neurosurgical conditions. We hypothesize that closure ICP also correlates with outcomes in ICH. METHODS: A multicentre retrospective study of 203 decompressive surgeries performed for ICHs was conducted (clot evacuation with either craniectomy or craniotomy). Receiver operating characteristic analysis on closure ICP was performed and an optimal threshold of 5 separated the patients into inadequate (iICP; ICP > 5 mmHg) and good decompression (gICP; ICP ≤ 5 mmHg). Postoperative ICP control, modified Rankin scale (mRS) and mortality were reported. RESULTS: There were 85 patients in the iICP and 118 patients in the gICP group respectively. The mean age, median preoperative Glasgow coma scale, ICH laterality, location, and volume were similar. After multivariable analysis, the need for (OR 2.55 [1.31-4.97]) and the duration of postoperative hyperosmolar therapy (iICP: 3 days, gICP: 1 day; p = 0.045), and repeat surgery for refractory ICP (OR 5.80 [1.53-22]) were more likely in the iICP group. The likelihood of mRS improvement at 1-year follow up was significantly worse in the iICP group (OR 0.38 [0.17-0.83], p = 0.015). CONCLUSION: Closure ICP is an objective and reproducible surgical target. When planning for surgical decompression, obtaining closure ICP of ≤ 5 mmHg is potentially able to improve postoperative ICP management and optimise functional recovery in a well selected patient population.


Subject(s)
Cerebral Hemorrhage , Intracranial Pressure , Humans , Retrospective Studies , Treatment Outcome , Cerebral Hemorrhage/surgery , Glasgow Coma Scale , Decompression, Surgical , Hematoma/surgery
18.
Acta Neurochir (Wien) ; 165(3): 599-604, 2023 03.
Article in English | MEDLINE | ID: mdl-36808008

ABSTRACT

PURPOSE: Reperfusion therapy has greatly improved outcomes of ischaemic stroke but remains associated with haemorrhagic conversion and early deterioration in a significant proportion of patients. Outcomes in terms of function and mortality are mixed and the evidence for decompressive craniectomies (DC) in this context remains sparse. We aim to investigate the clinical efficacy of DC in this group of patients compared to those without prior reperfusion therapy. METHODS: A multicentre retrospective study was conducted between 2005 and 2020, and all patients with DC for large territory infarctions were included. Outcomes in terms of inpatient and long-term modified Rankin scale (mRS) and mortality were assessed at various time points and compared using both univariable and multivariable analyses. Favourable mRS was defined as 0-3. RESULTS: There were 152 patients included in the final analysis. The cohort had a mean age of 57.5 years and median Charlson comorbidity index of 2. The proportion of preoperative anisocoria was 15.1%, median preoperative Glasgow coma scale was 9, the ratio of left-sided stroke was 40.1%, and ICA infarction was 42.8%. There were 79 patients with prior reperfusion and 73 patients without. After multivariable analysis, the proportion of favourable 6-month mRS (reperfusion, 8.2%; no reperfusion, 5.4%) and 1-year mortality (reperfusion, 26.7%; no reperfusion, 27.3%) were similar in both groups. Subgroup analysis of thrombolysis and/or thrombectomy against no reperfusion was also unremarkable. CONCLUSION: Reperfusion therapy prior to DC performed for large territory cerebral infarctions does not affect the functional outcome and mortality in a well-selected patient population.


Subject(s)
Brain Ischemia , Decompressive Craniectomy , Stroke , Humans , Middle Aged , Retrospective Studies , Brain Ischemia/surgery , Infarction, Middle Cerebral Artery/surgery , Stroke/surgery , Treatment Outcome
19.
Rev Esp Enferm Dig ; 115(4): 162-167, 2023 04.
Article in English | MEDLINE | ID: mdl-35791792

ABSTRACT

OBJECTIVES: to evaluate the performance of magnetic resonance elastography (MRE) to stage liver fibrosis in patients with histologically confirmed nonalcoholic fatty liver disease (NAFLD) and to assess the impact of potential confounding factors in MRE diagnostic accuracy. The secondary objective was to compare MRE with other non-invasive methods for staging fibrosis such as transient elastography (TE) and non-invasive scores (APRI and FIB-4). METHODS: sixty-five histologically confirmed NAFLD patients were prospectively enrolled at the Hospital Universitario Virgen del Rocío (Seville, Spain). Liver stiffness was measured by MRE, TE and non-invasive scores (APRI and FIB-4). Fibrosis was assessed by liver biopsy using the steatosis, activity and fibrosis (SAF) score. Patients were classified into three groups according to the consistency between MRE and histopathological findings: underestimation, concordance and overestimation groups. Areas under the ROC curve (AUROC) and diagnostic performance were evaluated. RESULTS: the area under the ROC curve (AUROC) of MRE in advanced fibrosis (≥ F3) was 0.90 (0.82-0.97), while TE AUROC was 0.82 (0.72-0.93) (p = 0.22) and lower for the non-invasive test (FIB-4 0.67 and APRI 0.62). Inflammatory activity, steatosis grade and higher levels of liver biochemistry appeared to overestimate MRE results in the univariate analysis, but only gamma-glutamyl transferase (GGT) was statistically significant in the multivariate analysis (p < 0.01). Age, sex, body mass index (BMI), weight, diabetes mellitus (DM), high blood pressure (HBP), platelets or lipidic profile did not affect MRE accuracy. CONCLUSIONS: MRE is an effective and non-invasive method for detecting and staging liver fibrosis in NAFLD patients. MRE is more accurate than TE and allows the study of liver anatomy. Histological inflammation and surrogate biomarkers of inflammation can overestimate liver stiffness, but only GGT was statistically significant in the multivariate analysis. Important features of NAFLD patients such as obesity, DM, or lipidic profile did not affect MRE accuracy.


Subject(s)
Elasticity Imaging Techniques , Non-alcoholic Fatty Liver Disease , Humans , Non-alcoholic Fatty Liver Disease/complications , Elasticity Imaging Techniques/methods , Magnetic Resonance Imaging/methods , Liver/diagnostic imaging , Liver/pathology , Liver Cirrhosis/complications , Fibrosis , Inflammation , ROC Curve , Biopsy
20.
Mol Cancer ; 21(1): 52, 2022 02 14.
Article in English | MEDLINE | ID: mdl-35164788

ABSTRACT

Abnormal N6-methyladenosine (m6A) modification is closely associated with the occurrence, development, progression and prognosis of cancer, and aberrant m6A regulators have been identified as novel anticancer drug targets. Both traditional medicine-related approaches and modern drug discovery platforms have been used in an attempt to develop m6A-targeted drugs. Here, we provide an update of the latest findings on m6A modification and the critical roles of m6A modification in cancer progression, and we summarize rational sources for the discovery of m6A-targeted anticancer agents from traditional medicines and computer-based chemosynthetic compounds. This review highlights the potential agents targeting m6A modification for cancer treatment and proposes the advantage of artificial intelligence (AI) in the discovery of m6A-targeting anticancer drugs. Three stages of m6A-targeting anticancer drug discovery: traditional medicine-based natural products, modern chemical modification or synthesis, and artificial intelligence (AI)-assisted approaches for the future.


Subject(s)
Artificial Intelligence , Neoplasms , Adenosine/chemistry , Drug Discovery , Humans , Neoplasms/drug therapy , Neoplasms/genetics , Prognosis
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