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1.
Bioengineering (Basel) ; 11(1)2023 Dec 26.
Article de Anglais | MEDLINE | ID: mdl-38247902

RÉSUMÉ

Extracorporeal membrane oxygenation (ECMO) is a vital emergency procedure providing respiratory and circulatory support to critically ill patients, especially those with compromised cardiopulmonary function. Its use has grown due to technological advances and clinical demand. Prolonged ECMO usage can lead to complications, necessitating the timely assessment of peripheral microcirculation for an accurate physiological evaluation. This study utilizes non-invasive near-infrared spectroscopy (NIRS) to monitor knee-level microcirculation in ECMO patients. After processing oxygenation data, machine learning distinguishes high and low disease severity in the veno-venous (VV-ECMO) and veno-arterial (VA-ECMO) groups, with two clinical parameters enhancing the model performance. Both ECMO modes show promise in the clinical severity diagnosis. The research further explores statistical correlations between the oxygenation data and disease severity in diverse physiological conditions, revealing moderate correlations with the acute physiologic and chronic health evaluation (APACHE II) scores in the VV-ECMO and VA-ECMO groups. NIRS holds the potential for assessing patient condition improvements.

2.
Nanomaterials (Basel) ; 12(14)2022 Jul 18.
Article de Anglais | MEDLINE | ID: mdl-35889678

RÉSUMÉ

Photonic crystals possess metastructures with a unique dispersion relation. An integrated optical circuit plays a crucial role in quantum computing, for which miniaturized optical components can be designed according to the characteristics of photonic crystals. Because the stable light transmission mode for a square waveguide is transverse electric or transverse magnetic polarization, we designed a half-waveplate element with a photonic crystal that can rotate the polarization direction of the light incident on a waveguide by 90°. Using the dispersion relation of photonic crystals, the polarization rotation length and the optical axis's angle of deviation from the electric field in the eigenmode can be effectively calculated. Polarization rotators designed on the basis of photonic crystal structures can effectively reduce the insertion loss of components and exhibit favorable polarization rotation performance.

3.
Open Forum Infect Dis ; 8(9): ofab416, 2021 Sep.
Article de Anglais | MEDLINE | ID: mdl-34557557

RÉSUMÉ

BACKGROUND: The factors that predict the progression of Mycoplasma pneumoniae infection remain inconclusive. Therefore, we investigated macrolide resistance prevalence, M pneumoniae genotype, and clinical characteristics of childhood M pneumoniae respiratory tract infections in Taiwan. METHODS: A total of 295 children hospitalized with respiratory tract infections with positive serological M pneumoniae immunoglobulin M test results were enrolled in this 3-year prospective study. Oropharyngeal swabs were obtained for M pneumoniae cultures and polymerase chain reaction tests. All M pneumoniae specimens were further characterized by P1 typing, multilocus variable-number tandem-repeat analysis (MLVA), and macrolide resistance genotyping. The clinical characteristics and blood cytokine profiles were analyzed accordingly. RESULTS: Of 138 M pneumoniae specimens, type I P1 was the predominant (136 of 138, 98.6%). The MLVA type P (4-4-5-7-2) was the leading strain (42 of 138, 30.4%), followed by type J, U, A, and X. The overall macrolide-resistant rate was 38.4% (53 of 138); the resistance rate increased dramatically yearly: 10.6% in 2017, 47.5% in 2018, and 62.5% in 2019 (P < .001). All macrolide-resistant M pneumoniae (MRMP) harbored the A2063G mutation and were MLVA type 4-5-7-2 (49 of 53, 92.5%), especially type U and X. No significant differences in clinical symptoms, duration of hospital stay, and radiographic findings were identified among patients between MRMP and macrolide-sensitive M pneumoniae (MSMP) groups. Patients with MRMP infection had more febrile days before and during hospitalization and higher interleukin (IL)-13 and IL-33 levels than patients with MSMP infection (P < .05). CONCLUSIONS: Macrolide-resistant M pneumoniae surged in Taiwan throughout the study period, but macrolide resistance was not a determinant factor of clinical severity.

4.
J Med Internet Res ; 22(9): e22181, 2020 09 21.
Article de Anglais | MEDLINE | ID: mdl-32924951

RÉSUMÉ

BACKGROUND: Real-time global mental health surveillance is urgently needed for tracking the long-term impact of the COVID-19 pandemic. OBJECTIVE: This study aimed to use Google Trends data to investigate the impact of the pandemic on global mental health by analyzing three keywords indicative of mental distress: "insomnia," "depression," and "suicide." METHODS: We examined increases in search queries for 19 countries. Significant increases were defined as the actual daily search value (from March 20 to April 19, 2020) being higher than the 95% CIs of the forecast from the 3-month baseline via ARIMA (autoregressive integrated moving average) modeling. We examined the correlation between increases in COVID-19-related deaths and the number of days with significant increases in search volumes for insomnia, depression, and suicide across multiple nations. RESULTS: The countries with the greatest increases in searches for insomnia were Iran, Spain, the United States, and Italy; these countries exhibited a significant increase in insomnia searches on more than 10 of the 31 days observed. The number of COVID-19-related deaths was positively correlated to the number of days with an increase in searches for insomnia in the 19 countries (ρ=0.64, P=.003). By contrast, there was no significant correlation between the number of deaths and increases in searches for depression (ρ=-0.12, P=.63) or suicide (ρ=-0.07, P=.79). CONCLUSIONS: Our analysis suggests that insomnia could be a part of routine mental health screening during the COVID-19 pandemic.


Sujet(s)
Infections à coronavirus/épidémiologie , Santé mondiale/statistiques et données numériques , Internationalité , Internet/statistiques et données numériques , Santé mentale/statistiques et données numériques , Pandémies , Pneumopathie virale/épidémiologie , Moteur de recherche/statistiques et données numériques , Troubles de l'endormissement et du maintien du sommeil/épidémiologie , Betacoronavirus , COVID-19 , Dépression/épidémiologie , Humains , Études longitudinales , SARS-CoV-2 , Suicide/statistiques et données numériques
5.
JMIR Mhealth Uhealth ; 8(2): e16063, 2020 02 25.
Article de Anglais | MEDLINE | ID: mdl-32130165

RÉSUMÉ

BACKGROUND: There are numerous mobile apps for tracking work hours, but only a few of them record work hours automatically instead of relying on manual logging. No apps have been customized for medical staff, whose work schedules are highly complicated as they have both regular hours and on-call duties. OBJECTIVE: The specific aims of this study were to (1) identify the Staff Hours app users' GPS-defined work hours, (2) examine the overtime work hours from the app-recorded total work hours and the participants' self-reported scheduled work hours, and (3) compare these app-recorded total work hours among different occupations. METHODS: We developed an app, Staff Hours, to automatically calculate a user's work hours via GPS background data. Users can enter their scheduled hours, including regular hours and on-call duties. The app automatically generates overtime reports by comparing the app-recorded total work hours with the user-defined scheduled hours. A total of 183 volunteers (60 females and 123 males; mean age 32.98 years, SD 6.74) were included in this study. Most of the participants (162/183, 88.5%) were medical staff, and their positions were resident physicians (n=89), visiting staff (n=38), medical students (n=10), registered nurses (n=25), and non-health care professionals (non-HCPs; n=21). RESULTS: The total work hours (mean 55.69 hours, SD 21.34) of the 183 participants were significantly higher than their scheduled work hours (mean 50.67 hours, SD 21.44; P=.01). Medical staff had significantly longer total work hours (mean 57.01 hours, SD 21.20) than non-HCPs (mean 45.48 hours, SD 20.08; P=.02). Residents (mean 60.38 hours, SD 18.67) had significantly longer work hours than visiting staff (mean 51.42 hours, SD 20.33; P=.03) and non-HCPs (mean 45.48 hours, SD 20.08; P=.004). CONCLUSIONS: Staff Hours is the first automatic GPS location-based app designed for medical staff to track work hours and calculate overtime. For medical staff, this app could keep complete and accurate records of work hours in real time, reduce bias, and allow for better complying with labor regulations.


Sujet(s)
Corps médical , Applications mobiles , Charge de travail/statistiques et données numériques , Adulte , Femelle , Humains , Mâle , Étudiant médecine
6.
Nat Cell Biol ; 20(8): 954-965, 2018 08.
Article de Anglais | MEDLINE | ID: mdl-30022119

RÉSUMÉ

BRCA1 deficiencies cause breast, ovarian, prostate and other cancers, and render tumours hypersensitive to poly(ADP-ribose) polymerase (PARP) inhibitors. To understand the resistance mechanisms, we conducted whole-genome CRISPR-Cas9 synthetic-viability/resistance screens in BRCA1-deficient breast cancer cells treated with PARP inhibitors. We identified two previously uncharacterized proteins, C20orf196 and FAM35A, whose inactivation confers strong PARP-inhibitor resistance. Mechanistically, we show that C20orf196 and FAM35A form a complex, 'Shieldin' (SHLD1/2), with FAM35A interacting with single-stranded DNA through its C-terminal oligonucleotide/oligosaccharide-binding fold region. We establish that Shieldin acts as the downstream effector of 53BP1/RIF1/MAD2L2 to promote DNA double-strand break (DSB) end-joining by restricting DSB resection and to counteract homologous recombination by antagonizing BRCA2/RAD51 loading in BRCA1-deficient cells. Notably, Shieldin inactivation further sensitizes BRCA1-deficient cells to cisplatin, suggesting how defining the SHLD1/2 status of BRCA1-deficient tumours might aid patient stratification and yield new treatment opportunities. Highlighting this potential, we document reduced SHLD1/2 expression in human breast cancers displaying intrinsic or acquired PARP-inhibitor resistance.


Sujet(s)
Protéine BRCA1/génétique , Tumeurs osseuses/traitement médicamenteux , Tumeurs du sein/traitement médicamenteux , Réparation de l'ADN par jonction d'extrémités , Résistance aux médicaments antinéoplasiques , Ostéosarcome/traitement médicamenteux , Tumeurs de l'ovaire/traitement médicamenteux , Inhibiteurs de poly(ADP-ribose) polymérases/pharmacologie , Protéines/métabolisme , Réparation de l'ADN par recombinaison , Animaux , Protéine BRCA1/déficit , Tumeurs osseuses/génétique , Tumeurs osseuses/métabolisme , Tumeurs osseuses/anatomopathologie , Tumeurs du sein/génétique , Tumeurs du sein/métabolisme , Tumeurs du sein/anatomopathologie , Protéines du cycle cellulaire , Lignée cellulaire tumorale , Cisplatine/pharmacologie , Cassures double-brin de l'ADN , Protéines de liaison à l'ADN , Relation dose-effet des médicaments , Résistance aux médicaments antinéoplasiques/génétique , Femelle , Cellules HEK293 , Humains , Protéines Mad2/génétique , Protéines Mad2/métabolisme , Souris , Complexes multiprotéiques , Ostéosarcome/génétique , Ostéosarcome/métabolisme , Ostéosarcome/anatomopathologie , Tumeurs de l'ovaire/génétique , Tumeurs de l'ovaire/métabolisme , Tumeurs de l'ovaire/anatomopathologie , Protéines/génétique , Protéines télomériques/génétique , Protéines télomériques/métabolisme , Protéine-1 liant le suppresseur de tumeur p53/génétique , Protéine-1 liant le suppresseur de tumeur p53/métabolisme , Tests d'activité antitumorale sur modèle de xénogreffe
7.
Sci Rep ; 6: 24356, 2016 Apr 15.
Article de Anglais | MEDLINE | ID: mdl-27079678

RÉSUMÉ

The RNA-guided Cas9 nuclease is being widely employed to engineer the genomes of various cells and organisms. Despite the efficient mutagenesis induced by Cas9, off-target effects have raised concerns over the system's specificity. Recently a "double-nicking" strategy using catalytic mutant Cas9(D10A) nickase has been developed to minimise off-target effects. Here, we describe a Cas9(D10A)-based screening approach that combines an All-in-One Cas9(D10A) nickase vector with fluorescence-activated cell sorting enrichment followed by high-throughput genotypic and phenotypic clonal screening strategies to generate isogenic knockouts and knock-ins highly efficiently, with minimal off-target effects. We validated this approach by targeting genes for the DNA-damage response (DDR) proteins MDC1, 53BP1, RIF1 and P53, plus the nuclear architecture proteins Lamin A/C, in three different human cell lines. We also efficiently obtained biallelic knock-in clones, using single-stranded oligodeoxynucleotides as homologous templates, for insertion of an EcoRI recognition site at the RIF1 locus and introduction of a point mutation at the histone H2AFX locus to abolish assembly of DDR factors at sites of DNA double-strand breaks. This versatile screening approach should facilitate research aimed at defining gene functions, modelling of cancers and other diseases underpinned by genetic factors, and exploring new therapeutic opportunities.


Sujet(s)
Systèmes CRISPR-Cas , Deoxyribonuclease I/génétique , Deoxyribonuclease I/métabolisme , Édition de gène , Génotype , Phénotype , Allèles , Séquence nucléotidique , Lignée cellulaire , Découverte de médicament , Techniques de knock-out de gènes , Ordre des gènes , Ciblage de gène , Locus génétiques , Vecteurs génétiques/génétique , Génomique/méthodes , Tests de criblage à haut débit , Humains , Mutagenèse , , Facteur de croissance endothéliale vasculaire de type A/génétique
10.
Mol Cell Biol ; 33(9): 1746-55, 2013 May.
Article de Anglais | MEDLINE | ID: mdl-23438600

RÉSUMÉ

Yju2 is an essential splicing factor required for the first catalytic step after the action of Prp2. We dissected the structure of Yju2 and found that the amino (Yju2-N) and carboxyl (Yju2-C) halves of the protein can be separated and reconstituted for Yju2 function both in vivo and in vitro. Yju2-N has a weak affinity for the spliceosome but functions in promoting the first reaction, with the second reaction being severely impeded. The association of Yju2-N with the spliceosome is stabilized by the presence of Yju2-C at both the precatalytic and postcatalytic stages. Strikingly, Yju2-N supported a low level of the second reaction even in the absence of Prp16. Prp16 is known to mediate destabilization of Yju2 and Cwc25 after the first reaction to allow progression of the second reaction. We propose that in the absence of the C domain, Yju2-N is not stably associated with the spliceosome after lariat formation, and thus bypasses the need for Prp16. We also showed, by UV cross-linking, that Yju2 directly contacts U2 snRNA primarily in the helix II region both pre- and postcatalytically and in the branch-binding region only at the precatalytic stage, suggesting a possible role for Yju2 in positioning the branch point during the first reaction.


Sujet(s)
Adenosine triphosphatases/métabolisme , Protéines nucléaires/métabolisme , RNA helicases/métabolisme , Protéines de Saccharomyces cerevisiae/métabolisme , Saccharomyces cerevisiae/métabolisme , Splicéosomes/métabolisme , Séquence nucléotidique , Données de séquences moléculaires , Protéines nucléaires/composition chimique , Liaison aux protéines , Structure tertiaire des protéines , Épissage des ARN , Facteurs d'épissage des ARN , Petit ARN nucléaire/composition chimique , Petit ARN nucléaire/métabolisme , Saccharomyces cerevisiae/composition chimique , Saccharomyces cerevisiae/cytologie , Protéines de Saccharomyces cerevisiae/composition chimique
11.
Article de Anglais | MEDLINE | ID: mdl-21821900

RÉSUMÉ

The regulatory domain (PA3346RS), comprising the receiver and stalk domains, of the response regulator PA3346 requires phosphorylation for activation with magnesium ions as cofactors in order to modulate the downstream protein phosphatase activity for the regulation of swarming motility in Pseudomonas aeruginosa PAO1. Fusion-tagged recombinant PA3346RS of total molecular mass 25.3 kDa has been overexpressed in Escherichia coli, purified using Ni(2+)-NTA and Q-Sepharose ion-exchange columns and crystallized using the hanging-drop vapour-diffusion method. X-ray diffraction data were collected from PA3346RS crystals to 2.0 Šresolution. The crystal belonged to space group P4(1) or P4(3), with unit-cell parameters a = 82.38, c = 73.34 Å. Preliminary analysis indicated the presence of a dimer of PA3346RS in the asymmetric unit, with a solvent content of 48.6%.


Sujet(s)
Protéines bactériennes/composition chimique , Pseudomonas aeruginosa/composition chimique , Protéines bactériennes/isolement et purification , Cristallisation , Cristallographie aux rayons X
12.
J Biol Chem ; 285(50): 39500-10, 2010 Dec 10.
Article de Anglais | MEDLINE | ID: mdl-20819954

RÉSUMÉ

Aminoacylhistidine dipeptidases (PepD, EC 3.4.13.3) belong to the family of M20 metallopeptidases from the metallopeptidase H clan that catalyze a broad range of dipeptide and tripeptide substrates, including L-carnosine and L-homocarnosine. Homocarnosine has been suggested as a precursor for the neurotransmitter γ-aminobutyric acid (GABA) and may mediate the antiseizure effects of GABAergic therapies. Here, we report the crystal structure of PepD from Vibrio alginolyticus and the results of mutational analysis of substrate-binding residues in the C-terminal as well as substrate specificity of the PepD catalytic domain-alone truncated protein PepD(CAT). The structure of PepD was found to exist as a homodimer, in which each monomer comprises a catalytic domain containing two zinc ions at the active site center for its hydrolytic function and a lid domain utilizing hydrogen bonds between helices to form the dimer interface. Although the PepD is structurally similar to PepV, which exists as a monomer, putative substrate-binding residues reside in different topological regions of the polypeptide chain. In addition, the lid domain of the PepD contains an "extra" domain not observed in related M20 family metallopeptidases with a dimeric structure. Mutational assays confirmed both the putative di-zinc allocations and the architecture of substrate recognition. In addition, the catalytic domain-alone truncated PepD(CAT) exhibited substrate specificity to l-homocarnosine compared with that of the wild-type PepD, indicating a potential value in applications of PepD(CAT) for GABAergic therapies or neuroprotection.


Sujet(s)
Dipeptidases/composition chimique , Régulation de l'expression des gènes bactériens , Régulation de l'expression des gènes codant pour des enzymes , Vibrio alginolyticus/enzymologie , Acides aminés/composition chimique , Domaine catalytique , Cristallographie aux rayons X/méthodes , Analyse de mutations d'ADN/méthodes , Liaison hydrogène , Cinétique , Conformation moléculaire , Mutagenèse dirigée , Conformation des protéines , Structure tertiaire des protéines , Spécificité du substrat
13.
Mol Cell Biol ; 29(21): 5671-8, 2009 Nov.
Article de Anglais | MEDLINE | ID: mdl-19704000

RÉSUMÉ

Cwc25 has previously been identified to associate with pre-mRNA splicing factor Cef1/Ntc85, a component of the Prp19-associated complex (nineteen complex, or NTC) involved in spliceosome activation. We show here that Cwc25 is neither tightly associated with NTC nor required for spliceosome activation but is required for the first catalytic reaction. The affinity-purified spliceosome formed in Cwc25-depleted extracts contained only pre-mRNA and could be chased into splicing intermediates upon the addition of recombinant Cwc25 in an ATP-independent manner, suggesting that Cwc25 functions in the final step of the first catalytic reaction after the action of Prp2. Yju2 and a heat-resistant factor of unknown identity, HP, have previously been shown to be required for the same step of the splicing pathway. Cwc25, although resistant to heat treatment, is not sufficient to replace the function of HP, indicating that another heat-resistant factor, which we named HP-X, is involved. The requirement of Cwc25 and HP-X for the first catalytic reaction could be partially compensated for when the affinity-purified spliceosome was incubated in the presence of low concentrations of Mn(2+). These results have implications for the possible roles of Cwc25 and HP-X in facilitating juxtaposition of the 5' splice site and the branch point during the first catalytic reaction.


Sujet(s)
Biocatalyse , DEAD-box RNA helicases/métabolisme , Protéines nucléaires/métabolisme , Épissage des ARN/génétique , Protéines de Saccharomyces cerevisiae/métabolisme , Saccharomyces cerevisiae/métabolisme , Biocatalyse/effets des médicaments et des substances chimiques , Température élevée , Manganèse/pharmacologie , Complexes multiprotéiques/métabolisme , Liaison aux protéines/effets des médicaments et des substances chimiques , Précurseurs des ARN/métabolisme , Épissage des ARN/effets des médicaments et des substances chimiques , Facteurs d'épissage des ARN , Saccharomyces cerevisiae/effets des médicaments et des substances chimiques , Splicéosomes/effets des médicaments et des substances chimiques , Splicéosomes/métabolisme
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