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Twenty-seven rosmarinic acid derivatives were synthesized, among which compound RA-N8 exhibited the most potent antibacterial ability. The minimum inhibition concentration of RA-N8 against both S. aureus (ATCC 29213) and MRSA (ATCC BAA41 and ATCC 43300) was found to be 6 µg/mL, and RA-N8 killed E. coli (ATCC 25922) at 3 µg/mL in the presence of polymyxin B nonapeptide (PMBN) which increased the permeability of E. coli. RA-N8 exhibited a weak hemolytic effect at the minimum inhibitory concentration. SYTOX Green assay, SEM, and LIVE/DEAD fluorescence staining assay proved that the mode of action of RA-N8 is targeting bacterial cell membranes. Furthermore, no resistance in wildtype S. aureus developed after incubation with RA-N8 for 20 passages. Cytotoxicity studies further demonstrated that RA-N8 is non-toxic to the human normal cell line (HFF1). RA-N8 also exerted potent inhibitory ability against biofilm formation of S. aureus and even collapsed the shaped biofilm.
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Antibacterianos , Staphylococcus aureus Resistente a Meticilina , Humanos , Antibacterianos/química , Staphylococcus aureus , Ácido Rosmarínico , Escherichia coli , Relación Estructura-Actividad , Pruebas de Sensibilidad Microbiana , BiopelículasRESUMEN
PURPOSE: To investigate the effectiveness of physiotherapy interventions compared to control conditions on fecal incontinence (FI) and quality of life (QoL) following colorectal surgery. METHODS: Electronic searches in English-language (Scopus, Web of Science, Embase, AMED, CENTRAL, CINAHL, MEDLINE, Ovid, and PEDro) and Chinese-language (CNKI, Wanfang Data) databases were conducted. Trials comparing physiotherapy interventions against control conditions and assessing FI and QoL outcomes were included in the review. RESULTS: Ten trials were included. Meta-analysis revealed statistically significant improvements in lifestyle (0.54; 95% CI 0.03, 1.05; p = 0.04), coping behavior (MD 1.136; 95% CI 0.24, 2.04; p = 0.01), and embarrassment (0.417; 95% CI 0.14, 0.70; p = 0.00) components of QoL among individuals receiving pelvic floor muscle training (PFMT) compared with those receiving usual care (UC). Meta-analysis showed biofeedback to be significantly more effective than UC in enhancing anal resting pressure (ARP; 9.551; 95% CI 2.60, 16.51; p = 0.007), maximum squeeze pressure (MSP; 25.29; 95% CI 4.08, 48.50; p = 0.02), and rectal resting pressure (RRP; 0.51; 95% CI 0.10, 0.9; p = 0.02). Meta-analysis also found PFMT combined with biofeedback to be significantly more effective than PFMT alone for ARP (3.00; 95% CI 0.40, 5.60; p = 0.02), MSP (9.35, 95% CI 0.17, 18.53; p = 0.05), and RRP (1.54; 95% CI 0.60, 2.47; p = 0.00). CONCLUSIONS: PFMT combined with biofeedback was more effective than PFMT alone, but both interventions delivered alone were superior to UC. Future studies remain necessary to optimize and standardize the PFMT parameters for improving QoL among individuals who experience FI following CRC surgery. REVIEW REGISTRATION: This systematic review is registered in the PROSPERO registry (Ref: CRD42022337084).
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Cirugía Colorrectal , Incontinencia Fecal , Humanos , Calidad de Vida , Incontinencia Fecal/etiología , Incontinencia Fecal/terapia , Terapia por Ejercicio , Diafragma Pélvico , Ensayos Clínicos Controlados Aleatorios como Asunto , Modalidades de FisioterapiaRESUMEN
BACKGROUND: With the increasing threat of hazardous events at local, national, and global levels, an effective workforce for health emergency and disaster risk management (Health EDRM) in local, national, and international communities is urgently needed. However, there are no universally accepted competencies and curricula for Health EDRM. This study aimed to identify Health EDRM competencies and curricula worldwide using literature reviews and a cross-sectional survey. METHODS: Literature reviews in English and Japanese languages were performed. We searched MEDLINE, EMBASE, CINAHL (English), and the ICHUSHI (Japanese) databases for journal articles published between 1990 and 2020. Subsequently, a cross-sectional survey was sent to WHO Health EDRM Research Network members and other recommended experts in October 2021 to identify competency models and curricula not specified in the literature search. RESULTS: Nineteen studies from the searches were found to be relevant to Health EDRM competencies and curricula. Most of the competency models and curricula were from the US. The domains included knowledge and skills, emergency response systems (including incident management principles), communications, critical thinking, ethical and legal aspects, and managerial and leadership skills. The cross-sectional survey received 65 responses with an estimated response rate of 25%. Twenty-one competency models and 20 curricula for managers and frontline personnel were analyzed; managers' decision-making and leadership skills were considered essential. CONCLUSION: An increased focus on decision-making and leadership skills should be included in Health EDRM competencies and curricula to strengthen the health workforce.
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Planificación en Desastres , Desastres , Humanos , Estudios Transversales , Curriculum , Gestión de RiesgosRESUMEN
FtsQBL is a transmembrane protein complex in the divisome of Escherichia coli that plays a critical role in regulating cell division. Although extensive efforts have been made to investigate the interactions between the three involved proteins, FtsQ, FtsB, and FtsL, the detailed interaction mechanism is still poorly understood. In this study, we used hydrogen-deuterium exchange mass spectrometry to investigate these full-length proteins and their complexes. We also dissected the structural dynamic changes and the related binding interfaces within the complexes. Our data revealed that FtsB and FtsL interact at both the periplasmic and transmembrane regions to form a stable complex. Furthermore, the periplasmic region of FtsB underwent significant conformational changes. With the help of computational modeling, our results suggest that FtsBL complexation may bring the respective constriction control domains (CCDs) in close proximity. We show that when FtsBL adopts a coiled-coil structure, the CCDs are fixed at a vertical position relative to the membrane surface; thus, this conformational change may be essential for FtsBL's interaction with other divisome proteins. In the FtsQBL complex, intriguingly, we show only FtsB interacts with FtsQ at its C-terminal region, which stiffens a large area of the ß-domain of FtsQ. Consistent with this, we found the connection between the α- and ß-domains in FtsQ is also strengthened in the complex. Overall, the present study provides important experimental evidence detailing the local interactions between the full-length FtsB, FtsL, and FtsQ protein, as well as valuable insights into the roles of FtsQBL complexation in regulating divisome activity.
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Proteínas de Ciclo Celular , Proteínas de Escherichia coli , Escherichia coli , Proteínas de la Membrana , Proteínas de Ciclo Celular/metabolismo , División Celular , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas de la Membrana/metabolismo , Conformación ProteicaRESUMEN
BACKGROUND: Coronavirus disease 2019 (COVID-19) has become a global pandemic. Clinical characteristics regarding secondary infections in patients with COVID-19 have been reported, but detailed microbiology, risk factors, and outcomes of secondary bloodstream infections (sBSIs) in patients with severe COVID-19 have not been well described. METHODS: We performed a multicenter case-control study including all hospitalized patients diagnosed with severe COVID-19 and blood cultures drawn from 1 March 2020 to 7 May 2020 at 3 academic medical centers in New Jersey. Data collection included demographics, clinical and microbiologic variables, and patient outcomes. Risk factors and outcomes were compared between cases (sBSI) and controls (no sBSI). RESULTS: A total of 375 hospitalized patients were included. There were 128 sBSIs during the hospitalization. For the first set of positive blood cultures, 117 (91.4%) were bacterial and 7 (5.5%) were fungal. Those with sBSI were more likely to have altered mental status, lower mean percentage oxygen saturation on room air, have septic shock, and be admitted to the intensive care unit compared with controls. In-hospital mortality was higher in those with an sBSI versus controls (53.1% vs 32.8%, Pâ =â .0001). CONCLUSIONS: We observed that hospitalized adult patients with severe COVID-19 and sBSI had a more severe initial presentation, prolonged hospital course, and worse clinical outcomes. To maintain antimicrobial stewardship principles, further prospective studies are necessary to better characterize risk factors and prediction modeling to better understand when to suspect and empirically treat for sBSIs in severe COVID-19.
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COVID-19 , Coinfección , Sepsis , Adulto , Estudios de Casos y Controles , Hospitalización , Humanos , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo , SARS-CoV-2RESUMEN
The ability of metallochaperones to allosterically regulate the binding/release of metal ions and to switch protein-binding partners along the metal delivery pathway is essential to the metallation of the metalloenzymes. Urease, catalyzing the hydrolysis of urea into ammonia and carbon dioxide, contains two nickel ions bound by a carbamylated lysine in its active site. Delivery of nickel ions for urease maturation is dependent on GTP hydrolysis and is assisted by four urease accessory proteins UreE, UreF, UreG, and UreH(UreD). Here, we determined the crystal structure of the UreG dimer from Klebsiella pneumoniae in complex with nickel and GMPPNP, a nonhydrolyzable analog of GTP. Comparison with the structure of the GDP-bound Helicobacter pylori UreG (HpUreG) in the UreG2F2H2 complex reveals large conformational changes in the G2 region and residues near the 66CPH68 metal-binding motif. Upon GTP binding, the side chains of Cys66 and His68 from each of the UreG protomers rotate toward each other to coordinate a nickel ion in a square-planar geometry. Mutagenesis studies on HpUreG support the conformational changes induced by GTP binding as essential to dimerization of UreG, GTPase activity, in vitro urease activation, and the switching of UreG from the UreG2F2H2 complex to form the UreE2G2 complex with the UreE dimer. The nickel-charged UreE dimer, providing the sole source of nickel, and the UreG2F2H2 complex could activate urease in vitro in the presence of GTP. Based on our results, we propose a mechanism of how conformational changes of UreG during the GTP hydrolysis/binding cycle facilitate urease maturation.
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Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Proteínas Portadoras/química , Proteínas Portadoras/metabolismo , Guanosina Trifosfato/metabolismo , Metalochaperonas/química , Metalochaperonas/metabolismo , Conformación Proteica , Ureasa/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Portadoras/genética , Activación Enzimática , Guanosina Trifosfato/química , Metalochaperonas/genética , Modelos Biológicos , Modelos Moleculares , Mutación , Níquel/química , Níquel/metabolismo , Proteínas de Unión a Fosfato , Unión Proteica , Multimerización de Proteína , Relación Estructura-ActividadRESUMEN
A cell-permeable ytterbium complex shows reversible binding with Hg2+ in aqueous solution and in vitroby off-on visible and NIR emission. The fast response and 150 nM sensitivity of Hg2+ detection is based upon FRET and the lanthanide antenna effect. The reversible Hg2+ detection can be performed in vitro, and the binding mechanism is suggested by NMR employing the motif structure in a La complex and by DFT calculations.
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Mercurio/análisis , Compuestos Organometálicos/química , Iterbio/química , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Humanos , Estructura Molecular , Compuestos Organometálicos/farmacología , Teoría CuánticaRESUMEN
Urease is a metalloenzyme essential for the survival of Helicobacter pylori in acidic gastric environment. Maturation of urease involves carbamylation of Lys219 and insertion of two nickel ions at its active site. This process requires GTP hydrolysis and the formation of a preactivation complex consisting of apo-urease and urease accessory proteins UreF, UreH, and UreG. UreF and UreH form a complex to recruit UreG, which is a SIMIBI class GTPase, to the preactivation complex. We report here the crystal structure of the UreG/UreF/UreH complex, which illustrates how UreF and UreH facilitate dimerization of UreG, and assembles its metal binding site by juxtaposing two invariant Cys66-Pro67-His68 metal binding motif at the interface to form the (UreG/UreF/UreH)2 complex. Interaction studies revealed that addition of nickel and GTP to the UreG/UreF/UreH complex releases a UreG dimer that binds a nickel ion at the dimeric interface. Substitution of Cys66 and His68 with alanine abolishes the formation of the nickel-charged UreG dimer. This nickel-charged UreG dimer can activate urease in vitro in the presence of the UreF/UreH complex. Static light scattering and atomic absorption spectroscopy measurements demonstrated that the nickel-charged UreG dimer, upon GTP hydrolysis, reverts to its monomeric form and releases nickel to urease. Based on our results, we propose a mechanism on how urease accessory proteins facilitate maturation of urease.
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Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Helicobacter pylori/enzimología , Ureasa/química , Ureasa/metabolismo , Cristalografía por Rayos X , Guanosina Trifosfato/farmacología , Helicobacter pylori/efectos de los fármacos , Hidrólisis/efectos de los fármacos , Iones , Modelos Moleculares , Níquel/farmacología , Multimerización de Proteína/efectos de los fármacosRESUMEN
Augmented reality (AR) and virtual reality (VR) are powerful technologies with proven utility and tremendous potential. Spine surgery, in particular, may benefit from these developing technologies for resident training, preoperative education for patients, surgical planning and execution, and patient rehabilitation. In this review, the history, current applications, challenges, and future of AR/VR in spine surgery are examined.
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Realidad Aumentada , Cirugía Asistida por Computador , Realidad Virtual , Humanos , Cuidados PreoperatoriosRESUMEN
Emotion dysregulation is common among individuals with autism spectrum disorder (ASD). This study examined the relationship between emotion dysregulation and resting heart rate variability (HRV), a marker of the autonomic nervous system, in ASD adolescents. Resting HRV data were collected from ASD (n = 23) and typically developing (TD) adolescents (n = 32) via short-term electrocardiogram. Parents/caregivers reported participants' level of emotion dysregulation with the Emotion Dysregulation Inventory (EDI). Controlling for the effects of age and gender, regression analyses revealed moderating effects of group, suggesting that lower resting HRV was more strongly associated with greater emotion dysregulation in ASD than TD adolescents. The results support the view that disruptions in autonomic functioning may contribute to emotion dysregulation in ASD.
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Trastorno del Espectro Autista , Humanos , Adolescente , Trastorno del Espectro Autista/psicología , Frecuencia Cardíaca/fisiología , Sistema Nervioso Autónomo , Electrocardiografía , Emociones/fisiologíaRESUMEN
We successfully developed a fluorescent drug sensor from clinically relevant New Delhi metallo-ß-lactamase-1 (NDM-1). The F70 residue was chosen to be replaced with a cysteine for conjugation with thiol-reactive fluorescein-5-maleimide to form fluorescent F70Cf, where "f" refers to fluorescein-5-maleimide. Our proteolytic studies of unlabeled F70C and labeled F70Cf monitored by electrospray ionization-mass spectrometry (ESI-MS) revealed that fluorescein-5-maleimide was specifically linked to C70 in 1:1 mole ratio (F70C:fluorophore). Our drug sensor (F70Cf) can detect the ß-lactam antibiotics cefotaxime and cephalothin by giving stronger fluorescence in the initial binding phase and then declining fluorescence signals as a result of the hydrolysis of the antibiotics into acid products. F70Cf can also detect non-ß-lactam inhibitors (e.g., l-captopril, d-captopril, dl-thiorphan, and thanatin). In all cases, F70Cf exhibits stronger fluorescence due to inhibitor binding and subsequently sustained fluorescence signals in a later stage. Native ESI-MS results show that F70Cf can bind to all four inhibitors. Moreover, our drug sensor is compatible with a high-throughput microplate reader and has the capability to perform in vitro drug screening.
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BACKGROUNDNovel biomarkers to identify infectious patients transmitting Mycobacterium tuberculosis are urgently needed to control the global tuberculosis (TB) pandemic. We hypothesized that proteins released into the plasma in active pulmonary TB are clinically useful biomarkers to distinguish TB cases from healthy individuals and patients with other respiratory infections.METHODSWe applied a highly sensitive non-depletion tandem mass spectrometry discovery approach to investigate plasma protein expression in pulmonary TB cases compared to healthy controls in South African and Peruvian cohorts. Bioinformatic analysis using linear modeling and network correlation analyses identified 118 differentially expressed proteins, significant through 3 complementary analytical pipelines. Candidate biomarkers were subsequently analyzed in 2 validation cohorts of differing ethnicity using antibody-based proximity extension assays.RESULTSTB-specific host biomarkers were confirmed. A 6-protein diagnostic panel, comprising FETUB, FCGR3B, LRG1, SELL, CD14, and ADA2, differentiated patients with pulmonary TB from healthy controls and patients with other respiratory infections with high sensitivity and specificity in both cohorts.CONCLUSIONThis biomarker panel exceeds the World Health Organization Target Product Profile specificity criteria for a triage test for TB. The new biomarkers have potential for further development as near-patient TB screening assays, thereby helping to close the case-detection gap that fuels the global pandemic.FUNDINGMedical Research Council (MRC) (MR/R001065/1, MR/S024220/1, MR/P023754/1, and MR/W025728/1); the MRC and the UK Foreign Commonwealth and Development Office; the UK National Institute for Health Research (NIHR); the Wellcome Trust (094000, 203135, and CC2112); Starter Grant for Clinical Lecturers (Academy of Medical Sciences UK); the British Infection Association; the Program for Advanced Research Capacities for AIDS in Peru at Universidad Peruana Cayetano Heredia (D43TW00976301) from the Fogarty International Center at the US NIH; the UK Technology Strategy Board/Innovate UK (101556); the Francis Crick Institute, which receives funding from UKRI-MRC (CC2112); Cancer Research UK (CC2112); and the NIHR Biomedical Research Centre of Imperial College NHS.
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Biomarcadores , Proteómica , Tuberculosis Pulmonar , Humanos , Biomarcadores/sangre , Proteómica/métodos , Masculino , Femenino , Adulto , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/sangre , Mycobacterium tuberculosis , Persona de Mediana Edad , Perú/epidemiología , Sudáfrica/epidemiología , Estudios de Casos y Controles , Sensibilidad y EspecificidadRESUMEN
The Filamenting temperature-sensitive mutant Z (FtsZ), an essential GTPase in bacterial cell division, is highly conserved among Gram-positive and Gram-negative bacteria and thus considered an attractive target to treat antibiotic-resistant bacterial infections. In this study, a new class of FtsZ inhibitors bearing the pyrimidine-quinuclidine scaffold was identified from structure-based virtual screening of natural product libraries. Iterative rounds of in silico studies and biological evaluation established the preliminary structure-activity relationships of the new compounds. Potent FtsZ inhibitors with low micromolar IC50 and antibacterial activity against S. aureus and E. coli were found. These findings support the use of virtual screening and structure-based design for the rational development of new antibacterial agents with innovative mechanisms of action.
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Antibacterianos/farmacología , Diseño de Fármacos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , GTP Fosfohidrolasas/antagonistas & inhibidores , Animales , Antibacterianos/química , Sitios de Unión , Bovinos , Evaluación Preclínica de Medicamentos , Escherichia coli/efectos de los fármacos , GTP Fosfohidrolasas/química , GTP Fosfohidrolasas/metabolismo , Guanosina Trifosfato/metabolismo , Humanos , Simulación del Acoplamiento Molecular , Conformación Proteica , Multimerización de Proteína/efectos de los fármacos , Estructura Cuaternaria de Proteína , Pirimidinas/química , Quinuclidinas/química , Homología de Secuencia de Aminoácido , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/enzimología , Relación Estructura-Actividad , Tubulina (Proteína)/químicaRESUMEN
Status epilepticus (SE) is a life-threatening condition and medical emergency which can have lifelong consequences, including neuronal death and alteration of neuronal networks, resulting in long-term neurologic and cognitive deficits in children. When standard pharmacological treatment for SE is not successful in controlling seizures, the condition evolves to refractory SE (rSE) and finally to super-refractory SE (srSE) if it exceeds 24 h despite using anaesthetics. In this systematic review, we present literature data on the potential uses of clinical neuromodulation techniques for the management of srSE in children, including electroconvulsive therapy, vagus nerve stimulation, and deep brain stimulation. The evaluation of these techniques is limited by the small number of published paediatric cases (n = 25, one with two techniques) in peer-reviewed articles (n = 18). Although neuromodulation strategies have not been tested through randomised, prospective controlled clinical trials, this review presents the existing data and the potential benefits of neuromodulation therapy, suggesting that these techniques, when available, could be considered at earlier stages within the course of srSE intending to prevent long-term neurologic complications. Clinical trials aiming to establish whether early intervention can prevent long-term sequelae are necessary in order to establish the potential clinical value of neuromodulation techniques for the treatment of srSE in children.
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Lemierre syndrome (LS) is a rare, serious infection that is often misdiagnosed, as it frequently mimics common upper respiratory infections. It is even rarer for LS to be preceded by a viral infection. We share a case of LS in a young man who presented to the Emergency Department with COVID-19 viral infection followed by a subsequent LS diagnosis. The patient's condition initially worsened despite treatments for COVID-19 and was subsequently started on broad-spectrum antibiotics. He was then diagnosed with LS after blood cultures grew Fusobacterium necrophorum, and antibiotics were adjusted accordingly, resulting in improvement of symptoms. Even though LS is often recognized as a sequela of bacterial pharyngitis, preceding viral infections, including COVID-19, might be a risk factor that contributes to the development of LS.
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BACKGROUND: Microscopic microvascular decompression (MVD) of the trigeminal nerve is the gold standard surgical treatment for medically refractory classical trigeminal neuralgia. Endoscopy has significantly advanced surgery and provides enhanced visualization of the cerebellopontine angle and its critical neurovascular structures. We present our initial experience of fully endoscopic microvascular decompression (e-MVD). METHODS: This retrospective case series investigated e-MVD performed from September 2016 to February 2020 at a single institution. Clinical data including presenting symptoms, medications, operative findings, postoperative complications, and outcomes were recorded. The 5-point Barrow Neurological Institute (BNI) pain intensity score was used to quantify patients' pain relief. RESULTS: During the study period, 25 patients with trigeminal neuralgia (10 males, 15 females; mean [SD] age = 63 [10.4] years) underwent e-MVD. All patients had a preoperative BNI score of V. The left side was affected in 15 patients. Complications occurred in 2 patients: both experienced hearing loss, and one experienced transient facial weakness 7 days after surgery. The facial weakness had resolved by the last follow-up. All patients were completely pain-free (BNI score I) immediately postoperatively. On latest follow-up, 22 patients have remained pain-free, and 3 patients have recurrent pain that is being controlled with medication (BNI score III). CONCLUSIONS: Our study demonstrated that e-MVD is a safe, possibly effective method of performing MVD with the added benefit of improved visualization of the operative field for the operating surgeon and the surgical team. Larger prospective studies are required to evaluate whether performing e-MVD confers any additional benefits in long-term clinical outcome of patients with trigeminal neuralgia.
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Cirugía para Descompresión Microvascular , Neuralgia del Trigémino , Endoscopía , Femenino , Humanos , Masculino , Cirugía para Descompresión Microvascular/métodos , Persona de Mediana Edad , Dolor/etiología , Estudios Retrospectivos , Resultado del Tratamiento , Neuralgia del Trigémino/complicaciones , Neuralgia del Trigémino/diagnóstico por imagen , Neuralgia del Trigémino/cirugíaRESUMEN
PURPOSE: Picture archiving and communication system (PACS) is a medical imaging system for sharing, storage, retrieval, and access of medical images stored. Our study aimed to identify ophthalmologists' views on PACS, with the comparison between 3 platforms, namely electronic patient record (ePR), HEYEX (Heidelberg Engineering, Switzerland), and FORUM (Zeiss, US), following their implementation in an eye hospital for common ophthalmic investigations [visual field, optical coherence tomography (OCT) of retinal nerve fiber layer and macula, and fluorescein/indocyanine green angiography (FA/ICG)]. METHODS: An online survey was distributed among ophthalmologists in a single center. Primary outcome included comparison of PACS with paper-based system. Secondary outcomes included pattern of use and comparison of different PACS platforms. RESULTS: Survey response rate was 28/37 (75.7%). Images were most commonly accessed through ePR (median: 80% of time, interquartile range: 50 to 90%).All systems scored highly in information display items (median scores ≥7.5 out of 10) and in reducing patient identification error in investigation filing and retrieval during consultation compared to paper (score ≥7.0). However, ePR was inferior to paper in "facilitating comparison with previous results" in all investigation types (scores 3.0 to 4.5). ePR scored significantly higher in all system quality items than HEYEX ( P â<â0.001) and FORUM ( P â<â0.022), except login response time ( P â=â0.081). HEYEX scored significantly higher among vitreoretinaluveitis members (VRU) for information quality items for OCT macula and FA/ICG [VRU: 10.0 (8.0 to 10.0), non-VRU: 8.0 (6.75 to 9.25), P â=â0.042]. CONCLUSIONS: Overall feedback for PACS among ophthalmologists was positive, with limitations of inefficiency in use of information, for example, comparison with previous results. Subspecialty played an important role in evaluating PACS.
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Oftalmólogos , Sistemas de Información Radiológica , Hospitales , Humanos , Encuestas y CuestionariosRESUMEN
Inhibition of bacterial cell division is a novel mechanistic action in the development of new antimicrobial agents. The FtsZ protein is an important antimicrobial drug target because of its essential role in bacterial cell division. In the present study, potential inhibitors of FtsZ were identified by virtual screening followed by in vivo and in vitro bioassays. One of the candidates, Dacomitinib (S2727), shows for the first time its potent inhibitory activity against the MRSA strains. The binding mode of Dacomitinib in FtsZ was analyzed by docking, and Asp199 and Thr265 are thought to be essential residues involved in the interactions.
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Antimicrobial resistance has attracted worldwide attention and remains an urgent issue to resolve. Discovery of novel compounds is regarded as one way to circumvent the development of resistance and increase the available treatment options. Gossypol is a natural polyphenolic aldehyde, and it has attracted increasing attention as a possible antibacterial drug. In this paper, we studied the antimicrobial properties (minimum inhibitory concentrations) of gossypol acetate against both Gram-positive and Gram-negative bacteria strains and dig up targets of gossypol acetate using in vitro assays, including studying its effects on functions (GTPase activity and polymerization) of Filamenting temperature sensitive mutant Z (FtsZ) and its interactions with FtsZ using isothermal titration calorimetry (ITC), and in vivo assays, including visualization of cell morphologies and proteins localizations using a microscope. Lastly, Bacterial membrane permeability changes were studied, and the cytotoxicity of gossypol acetate was determined. We also estimated the interactions of gossypol acetate with the promising target. We found that gossypol acetate can inhibit the growth of Gram-positive bacteria such as the model organism Bacillus subtilis and the pathogen Staphylococcus aureus [both methicillin-sensitive (MSSA) and methicillin-resistant (MRSA)]. In addition, gossypol acetate can also inhibit the growth of Gram-negative bacteria when the outer membrane is permeabilized by Polymyxin B nonapeptide (PMBN). Using a cell biological approach, we show that gossypol acetate affects cell division in bacteria by interfering with the assembly of the cell division FtsZ ring. Biochemical analysis shows that the GTPase activity of FtsZ was inhibited and polymerization of FtsZ was enhanced in vitro, consistent with the block to cell division in the bacteria tested. The binding mode of gossypol acetate in FtsZ was modeled using molecular docking and provides an understanding of the compound mode of action. The results point to gossypol (S2303) as a promising antimicrobial compound that inhibits cell division by affecting FtsZ polymerization and has potential to be developed into an effective antimicrobial drug by chemical modification to minimize its cytotoxic effects in eukaryotic cells that were identified in this work.