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1.
Cureus ; 16(4): e57822, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38721179

RESUMEN

This case report explores the complex diagnostic dilemma between the Chilaiditi sign and the pneumoperitoneum. The patient presented with chronic complaints of vague abdominal pain, abdominal distension, and breathlessness. A chest X-ray indicated an elevated right hemidiaphragm with transverse colon interposition, leading to the diagnosis of Chilaiditi's sign. Subsequent imaging, including abdominal ultrasound and contrast-enhanced computed tomography, revealed a large non-enhancing multilobulated multicystic mass adherent to the anterior wall of the uterus, raising suspicions of malignancy. Managed by gynecologists, the patient underwent a total abdominal hysterectomy, mass excision, and bilateral salpingo-oophorectomy. The discussion delves into Chilaiditi's sign, its historical context, and its complex pathophysiology involving intestinal, hepatic, and/or diaphragmatic components. Various anatomical and functional factors contributing to this condition are explored. This case highlights the importance of considering the Chilaiditi sign in patients with radiologic evidence of subdiaphragmatic air. It emphasizes the need for timely and accurate diagnosis to differentiate it from more severe conditions like pneumoperitoneum. Such consideration aids in optimizing management strategies and preventing unnecessary investigations.

2.
Cureus ; 16(4): e57757, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38716005

RESUMEN

Pulmonary tuberculosis is a notorious disease as it can cause severe morbidity and mortality. In this case, we discuss a 75-year-old male tuberculosis patient from a rural area with no underlying comorbidities who failed to continue anti-tubercular medication after two months. The case discusses the diagnostic modalities confirming the diagnosis, sputum culture for Mycobacterium tuberculosis, imaging studies, including X-ray and CT of the chest, and laboratory parameters for identifying pulmonary mycetoma. The patient is now on anti-tubercular therapy (isoniazid, rifampicin, pyrazinamide, and ethambutol combination) and the anti-fungal drug itraconazole. Though pharmacotherapy for the treatment of mycetoma in patients with tuberculosis has a minimal role, the more appropriate treatment is surgical excision via lobectomy. As the occurrence of tuberculosis and mycetoma is a rare phenomenon, it is essential to rule out aspergillosis as both have similar presenting symptoms. Diagnosis of this co-infection can be the crucial difference between morbidity and mortality.

3.
Cureus ; 16(4): e57739, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38716013

RESUMEN

It is rare for quadriparesis to manifest as a symptom of tropical illnesses. With a history of only one fever episode one week prior, our patient, a 48-year-old male with obesity and prediabetes, who was also known to have ankylosing spondylitis, presented with acute onset flaccid quadriparesis. He did not exhibit any additional symptoms of dengue, such as bleeding tendencies, petechial rashes, thrombocytopenia, or febrile episodes. Upon examination, it was discovered that he had extremely low serum potassium levels and was dengue non-specific antigen 1 (NS1) positive. His hyperinsulinemia, as seen by elevated C peptide levels, most likely caused a transcellular shift that was then triggered by the dengue infection, leading to hypokalemic paralysis.

4.
Cureus ; 16(1): e53271, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38435885

RESUMEN

Chylothorax delineates a state marked by the accumulation of chyle, an opalescent fluid laden with lipids, within the pleural cavity. This occurrence commonly ensues from the seepage of chyle originating from the thoracic duct, occasioned by trauma, surgical interventions, or underlying pathological conditions. This phenomenon induces respiratory distress, necessitating intricate and tailored interventions for its resolution. In this report, we present the case of a 27-year-old male who was admitted with a two-month history of symptoms, including dry cough, weakness, weight loss, and intermittent fever. Previously treated for pleural effusions and ascites, he was referred to our hospital with an intercostal drainage tube in place. Initial examinations revealed respiratory distress, fever, and bilateral pleural effusions. Laboratory results and fluid analysis indicated significant abnormalities, prompting further investigations, including CT scans and biopsies. The patient was diagnosed with chylothorax with chylous ascites due to abdominal tubular lymphadenopathy and hemophagocytic lymphohistiocytosis (HLH) and started on anti-tubercular therapy (AKT4) and octreotide. The patient was also initially managed with non-invasive ventilatory (NIV) support, intravenous antibiotics, nebulizations, an intercostal chest drain (ICD), and a thoracic duct embolization (TDE). Regular monitoring and collaboration between specialties were crucial, ultimately resulting in the removal of the drainage tube and the patient's stable discharge.

5.
mBio ; 15(3): e0296823, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38294237

RESUMEN

Of the approximately 10 million cases of Mycobacterium tuberculosis (Mtb) infections each year, over 10% are resistant to the frontline antibiotic isoniazid (INH). INH resistance is predominantly caused by mutations that decrease the activity of the bacterial enzyme KatG, which mediates the conversion of the pro-drug INH to its active form INH-NAD. We previously discovered an inhibitor of Mtb respiration, C10, that enhances the bactericidal activity of INH, prevents the emergence of INH-resistant mutants, and re-sensitizes a collection of INH-resistant mutants to INH through an unknown mechanism. To investigate the mechanism of action of C10, we exploited the toxicity of high concentrations of C10 to select for resistant mutants. We discovered two mutations that confer resistance to the disruption of energy metabolism and allow for the growth of Mtb in high C10 concentrations, indicating that growth inhibition by C10 is associated with inhibition of respiration. Using these mutants as well as direct inhibitors of the Mtb electron transport chain, we provide evidence that inhibition of energy metabolism by C10 is neither sufficient nor necessary to potentiate killing by INH. Instead, we find that C10 acts downstream of INH-NAD synthesis, causing Mtb to become particularly sensitive to inhibition of the INH-NAD target, InhA, without changing the concentration of INH-NAD or the activity of InhA, the two predominant mechanisms of potentiating INH. Our studies revealed that there exists a vulnerability in Mtb that can be exploited to render Mtb sensitive to otherwise subinhibitory concentrations of InhA inhibitor.IMPORTANCEIsoniazid (INH) is a critical frontline antibiotic to treat Mycobacterium tuberculosis (Mtb) infections. INH efficacy is limited by its suboptimal penetration of the Mtb-containing lesion and by the prevalence of clinical INH resistance. We previously discovered a compound, C10, that enhances the bactericidal activity of INH, prevents the emergence of INH-resistant mutants, and re-sensitizes a set of INH-resistant mutants to INH. Resistance is typically mediated by katG mutations that decrease the activation of INH, which is required for INH to inhibit the essential enzyme InhA. Our current work demonstrates that C10 re-sensitizes INH-resistant katG-hypomorphs without enhancing the activation of INH. We furthermore show that C10 causes Mtb to become particularly vulnerable to InhA inhibition without compromising InhA activity on its own. Therefore, C10 represents a novel strategy to curtail the development of INH resistance and to sensitize Mtb to sub-lethal doses of INH, such as those achieved at the infection site.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Humanos , Isoniazida/farmacología , Mycobacterium tuberculosis/genética , Antituberculosos/farmacología , Farmacorresistencia Bacteriana/genética , Proteínas Bacterianas/genética , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Mutación , Catalasa/genética , Pruebas de Sensibilidad Microbiana
6.
J Org Chem ; 89(1): 731-739, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38093677

RESUMEN

A selective [4 + 2] cycloaddition reaction of thiazolo-2-pyridones with arynes has been demonstrated. The developed protocol allows rapid access to highly functionalized, structurally complex thiazolo-fused bridged isoquinolones in high yields, which are susceptible to further late-stage functionalization.

7.
Cureus ; 15(11): e48496, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38074004

RESUMEN

Intrathoracic extrapulmonary hydatid disease is an uncommon variant of hydatidosis. In this report, we describe a rare case of a 53-year-old female who presented with a left-side massive hydropneumothorax, initially treated as tubercular empyema and later came out to be intrathoracic extrapulmonary hydatid disease, with no signs of primary lesion in the lung. This case was managed with an intercostal drain insertion followed by a thoracoscopic-guided excision of the cyst, which on histopathological examination confirmed the diagnosis. Also, the Echinococcus antibody IgG test confirmed the same. The patient was then initiated on oral albendazole which showed a drastic reduction in the intrapleural cysts, but the patient later developed non-resolving pyopneumothorax with a bronchopleural fistula. The patient is being managed conservatively at present with oral albendazole and chest drain and is later advised to undergo decortication surgery of the lung.

8.
Cureus ; 15(11): e48621, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38090426

RESUMEN

Chronic lower limb lymphedema is a challenging and often debilitating medical condition characterized by the abnormal accumulation of lymphatic fluid in the extremities, leading to persistent swelling and discomfort. While this condition can be caused by various underlying factors, early diagnosis, and appropriate management are crucial for improving the patient's quality of life. This case report presents the successful surgical management of chronic lower limb lymphedema in a 30-year-old male patient who had been grappling with this condition for a decade. The patient's journey from the onset of symptoms, including swelling and difficulty in walking, to the eventual diagnosis and treatment is documented herein. Despite seeking medical care from allopathic and homeopathic sources, the patient's condition continued to deteriorate over the years, underscoring the complexity of chronic lower limb lymphedema and its challenges in clinical management. This case highlights the importance of accurate diagnosis, multidisciplinary evaluation, and a comprehensive surgical approach in addressing the complexities of chronic lower limb lymphedema. It also sheds light on the potential complications that may arise during treatment and the postoperative care required to achieve a favorable outcome. By sharing this case, we aim to contribute to understanding this condition and provide insights into the effective management of chronic lower limb lymphedema.

9.
Cureus ; 15(10): e47935, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38034137

RESUMEN

Oscillometry, a non-invasive technique for assessing lung function, has gained significant recognition and importance in modern pulmonary medicine. This comprehensive review thoroughly explores its principles, applications, advantages, limitations, recent innovations, and future directions. Oscillometry's primary strength lies in its ability to offer a holistic assessment of lung mechanics. Unlike traditional spirometry, oscillometry captures the natural airflow during quiet breathing, making it suitable for patients of all ages and those with severe respiratory conditions. It provides a comprehensive evaluation of airway resistance, reactance, and compliance, offering insights into lung function that were previously challenging to obtain. In clinical practice, oscillometry finds extensive application in diagnosing and managing respiratory diseases. It plays a pivotal role in asthma, chronic obstructive pulmonary disease (COPD), and interstitial lung diseases. By detecting subtle changes in lung function before symptoms manifest, oscillometry facilitates early interventions, improving disease management and patient outcomes. Oscillometry's non-invasive and patient-friendly nature is precious in pediatric care, where traditional spirometry may be challenging for young patients. It aids in diagnosing and monitoring pediatric respiratory disorders, ensuring that children receive the care they need from an early age. Despite its many advantages, oscillometry faces challenges, such as the need for standardized protocols and the complexity of data interpretation. However, ongoing efforts to establish global standards and provide education and training for healthcare professionals aim to address these issues. Looking ahead, oscillometry holds great promise in the field of personalized medicine. With its ability to tailor treatment plans based on individualized lung function data, healthcare providers can optimize therapy selection and dosing, ultimately improving patient care and quality of life. In conclusion, oscillometry is poised to play an increasingly pivotal role in modern pulmonary medicine. As standardization efforts continue and technology evolves, it is an indispensable tool in the clinician's arsenal for diagnosing, managing, and personalizing respiratory care, ultimately leading to improved patient outcomes and better respiratory health.

11.
J Am Chem Soc ; 145(40): 22009-22018, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37754784

RESUMEN

Dynamic supramolecular polymers, with their functional similarities to classical covalent polymers and their adaptive and self-repairing nature reminiscent of biological assemblies, have emerged as highly promising systems for the design of smart soft materials. Recent advancements in mechanistic investigations and novel synthetic strategies, such as living supramolecular polymerization, have significantly enhanced our ability to control the primary structure of these supramolecular polymers. However, realizing their full functional potential requires expanding their topological diversity in a manner akin to classical polymers as well as achieving precise molecular organization at higher hierarchical levels of self-assembly. In this paper, we present a remarkable advancement in this field, introducing an unprecedented and controlled synthesis of secondary supramolecular polymers. Our innovative strategy combines chirality-controlled surface-catalyzed secondary nucleation and a bioinspired peptide design, effectively stabilizing higher-order assembly. Furthermore, by harnessing this stereoselective nucleation process, we demonstrate the successful synthesis of racemic supramolecular polymers featuring parallelly stacked conglomerate microstructures─a previously unreported topology in synthetic self-assembled systems. Additionally, we elucidate that the extent of secondary supramolecular polymers can be regulated by modulating the enantiomeric excess of the chiral monomers. Consequently, our study unveils new topologies that exhibit enhanced higher-order structural complexity in the realm of supramolecular polymers.

12.
Metab Syndr Relat Disord ; 21(9): 475-478, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37756226

RESUMEN

Background: Nonalcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease with increasing rates globally. Patients with type 2 diabetes mellitus have higher risk of developing NAFLD. Patients with a higher degree of liver fibrosis in NAFLD are at an increased risk for liver-related mortality, but get missed easily during the referral process. This project aims to improve early detection and linkage-to-care of fibrotic NAFLD patients. Methods: We utilized a combination of automated electronic health record (EHR)-based fibrosis (FIB)-4 score and directed provider education. A health-system wide FIB-4 score calculator that providers can easily add to their workflow for NAFLD patient triaging. Data were analyzed at 6 and 12 months after implementation. Results: Postimplementation, there was an increase in patients referred to hepatology with higher degree of liver fibrosis and decreased referral to hepatology with low risk of liver fibrosis, measured by FIB-4 score. At baseline, ∼55% of referred patient to hepatology had FIB-4 score <1.3 compared to 38% at 12 months postimplementation. There was an increase in referral of patients with FIB-4 scores >1.3 when compared to preinterventions, 62% versus 45%. This is most pronounced in patients with severe fibrotic disease with FIB-4 score >2.67, 30% versus 12%. Conclusions: Automated FIB-4 score in EHR can improve appropriate linkage-to-care for at-risk fibrotic NAFLD, especially when coupled with targeted provider education. The durability of such improvement is essential to study along with the need to increase broad acceptance across health systems.


Asunto(s)
Diabetes Mellitus Tipo 2 , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/patología , Hígado/patología , Fibrosis , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/patología
13.
J Med Chem ; 66(16): 11056-11077, 2023 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-37485869

RESUMEN

Mycobacterium tuberculosis (Mtb) drug resistance poses an alarming threat to global tuberculosis control. We previously reported that C10, a ring-fused thiazolo-2-pyridone, inhibits Mtb respiration, blocks biofilm formation, and restores the activity of the antibiotic isoniazid (INH) in INH-resistant Mtb isolates. This discovery revealed a new strategy to address INH resistance. Expanding upon this strategy, we identified C10 analogues with improved potency and drug-like properties. By exploring three heterocycle spacers (oxadiazole, 1,2,3-triazole, and isoxazole) on the ring-fused thiazolo-2-pyridone scaffold, we identified two novel isoxazoles, 17h and 17j. 17h and 17j inhibited Mtb respiration and biofilm formation more potently with a broader therapeutic window, were better potentiators of INH-mediated inhibition of an INH-resistant Mtb mutant, and more effectively inhibited intracellular Mtb replication than C10. The (-)17j enantiomer showed further enhanced activity compared to its enantiomer and the 17j racemic mixture. Our potent second-generation C10 analogues offer promise for therapeutic development against drug-resistant Mtb.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Humanos , Isoniazida/farmacología , Isoniazida/uso terapéutico , Antituberculosos/farmacología , Antituberculosos/uso terapéutico , Farmacorresistencia Bacteriana , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Isoxazoles/farmacología , Pruebas de Sensibilidad Microbiana , Proteínas Bacterianas
14.
Cureus ; 15(5): e39167, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37332463

RESUMEN

A winking coronary sign refers to the partial collapse of an artery situated over the ventricular septal rupture during systole and refilling of the same during diastole, which is seen as phasic filling and disappearance of the arterial segment during coronary angiography. In this article, we discuss the case of a patient who reported to the emergency department of a tertiary care hospital in central India with myocardial infarction of the anterior wall. Two-dimensional echocardiography and coronary angiography revealed ventricular septal rupture. The patient was promptly managed by a percutaneous coronary angiography and interventricular septal device closure. Even after the defect closure, the winking coronary sign persisted on coronary angiography, and the patient was then discharged in stable condition.

15.
mBio ; 14(3): e0044923, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-37120759

RESUMEN

Listeria monocytogenes is a facultative Gram-positive bacterium that causes listeriosis, a severe foodborne disease. We previously discovered that ring-fused 2-pyridone compounds can decrease virulence factor expression in Listeria by binding and inactivating the PrfA virulence activator. In this study, we tested PS900, a highly substituted 2-pyridone that was recently discovered to be bactericidal to other Gram-positive pathogenic bacteria, such as Staphylococcus aureus and Enterococcus faecalis. We show that PS900 can interact with PrfA and reduce the expression of virulence factors. Unlike previous ring-fused 2-pyridones shown to inactivate PrfA, PS900 had an additional antibacterial activity and was found to potentiate sensitivity toward cholic acid. Two PS900-tolerant mutants able to grow in the presence of PS900 carried mutations in the brtA gene, encoding the BrtA repressor. In wild-type (WT) bacteria, cholic acid binds and inactivates BrtA, thereby alleviating the expression of the multidrug transporter MdrT. Interestingly, we found that PS900 also binds to BrtA and that this interaction causes BrtA to dissociate from its binding site in front of the mdrT gene. In addition, we observed that PS900 potentiated the effect of different osmolytes. We suggest that the increased potency of cholic acid and osmolytes to kill bacteria in the presence of PS900 is due to the ability of the latter to inhibit general efflux, through a yet-unknown mechanism. Our data indicate that thiazolino 2-pyridones constitute an attractive scaffold when designing new types of antibacterial agents. IMPORTANCE Bacteria resistant to one or several antibiotics are a very large problem, threatening not only treatment of infections but also surgery and cancer treatments. Thus, new types of antibacterial drugs are desperately needed. In this work, we show that a new generation of substituted ring-fused 2-pyridones not only inhibit Listeria monocytogenes virulence gene expression, presumably by inactivating the PrfA virulence regulator, but also potentiate the bactericidal effects of cholic acid and different osmolytes. We identified a multidrug repressor as a second target of 2-pyridones. The repressor-2-pyridone interaction displaces the repressor from DNA, thus increasing the expression of a multidrug transporter. In addition, our data suggest that the new class of ring-fused 2-pyridones are efficient efflux inhibitors, possibly explaining why the simultaneous addition of 2-pyridones together with cholic acid or osmolytes is detrimental for the bacterium. This work proves conclusively that 2-pyridones constitute a promising scaffold to build on for future antibacterial drug design.


Asunto(s)
Listeria monocytogenes , Piridonas/farmacología , Piridonas/metabolismo , Factores de Virulencia/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Ácido Cólico/metabolismo , Ácido Cólico/farmacología , Antibacterianos/farmacología , Antibacterianos/metabolismo , Proteínas Bacterianas/metabolismo , Factores de Terminación de Péptidos/metabolismo , Regulación Bacteriana de la Expresión Génica
16.
bioRxiv ; 2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36798348

RESUMEN

Of the approximately 10 million cases of Mycobacterium tuberculosis (Mtb) infections each year, over 10% are resistant to the frontline antibiotic isoniazid (INH). INH resistance is predominantly caused by mutations that decrease the activity of the bacterial enzyme KatG, which mediates conversion of the pro-drug INH to its active form INH-NAD. We previously discovered an inhibitor of Mtb respiration, C10, that enhances the bactericidal activity of INH, prevents the emergence of INH-resistant mutants, and re-sensitizes a collection of INH-resistant mutants to INH through an unknown mechanism. To investigate the mechanism of action of C10, we exploited the toxicity of high concentrations of C10 to select for resistant mutants. We discovered two mutations that confer resistance to the disruption of energy metabolism and allow for growth of Mtb in high C10 concentrations, indicating that growth inhibition by C10 is associated with inhibition of respiration. Using these mutants as well as direct inhibitors of the Mtb electron transport chain, we provide evidence that inhibition of energy metabolism by C10 is neither sufficient nor necessary to potentiate killing by INH. Instead, we find that C10 acts downstream of INH-NAD synthesis, causing Mtb to become particularly sensitive to inhibition of the INH-NAD target, InhA, without changing the concentration of INH-NAD or the activity of InhA, the two predominant mechanisms of potentiating INH. Our studies revealed that there exists a vulnerability in Mtb that can be exploited to render Mtb sensitive to otherwise subinhibitory concentrations of InhA inhibitor.

17.
J Viral Hepat ; 30(5): 397-405, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36696286

RESUMEN

Expanding capacity to screen and treat those infected with the hepatitis C virus (HCV) is an essential element of the global elimination strategy. We evaluated the hub-and-spoke Project ECHO training versus telementoring models to educate, train and support HCV care by primary care providers in 13 targeted counties in northern California. A novel provider engagement strategy was used. Provider engagement and retention, time to readiness to treat HCV, and knowledge and confidence were the outcomes of interest. 94 participants from 60 unique clinics in the target counties participated in the ECHO-PLUS programme; 39.4% were physicians, 48.9% were advanced practice providers, and 11.7% were nurses. The median (range) participation time was 5 (1-49) hours. Confidence scores (minimum score = 13 and maximum score = 65) increased by a mean of 14.0 (SD:8.2) and 11.4 (SD:12.0) points for the hub-and-spoke and telementoring programmes, respectively (p = .53), with the largest changes in confidence seen in treating patients per guidelines, managing side effects and in serving as a consultant for HCV in their clinic. Among 24 participants with data on time to treatment, median time from beginner to experienced was 8 h (IQR:6-12) for hub-and-spoke and 2 h (IQR:1-2.4) for the telementoring programme (p = .01). A 'boots on the ground' approach to recruiting HCV champions was effective within rural communities. Both tele-ECHO hub-and-spoke and telementoring approaches to training primary care providers yielded increase in knowledge and confidence in HCV care and amplified the number of patients who were screened and treated. Telementoring accelerated the timeline of novice providers being 'ready to treat'.


Asunto(s)
Hepatitis C , Médicos , Humanos , Hepacivirus , Hepatitis C/terapia , Atención Primaria de Salud , California
18.
Proc Natl Acad Sci U S A ; 119(43): e2210912119, 2022 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-36252016

RESUMEN

The alarming rise of multidrug-resistant Gram-positive bacteria has precipitated a healthcare crisis, necessitating the development of new antimicrobial therapies. Here we describe a new class of antibiotics based on a ring-fused 2-pyridone backbone, which are active against vancomycin-resistant enterococci (VRE), a serious threat as classified by the Centers for Disease Control and Prevention, and other multidrug-resistant Gram-positive bacteria. Ring-fused 2-pyridone antibiotics have bacteriostatic activity against actively dividing exponential phase enterococcal cells and bactericidal activity against nondividing stationary phase enterococcal cells. The molecular mechanism of drug-induced killing of stationary phase cells mimics aspects of fratricide observed in enterococcal biofilms, where both are mediated by the Atn autolysin and the GelE protease. In addition, combinations of sublethal concentrations of ring-fused 2-pyridones and standard-of-care antibiotics, such as vancomycin, were found to synergize to kill clinical strains of VRE. Furthermore, a broad range of antibiotic resistant Gram-positive pathogens, including those responsible for the increasing incidence of antibiotic resistant healthcare-associated infections, are susceptible to this new class of 2-pyridone antibiotics. Given the broad antibacterial activities of ring-fused 2-pyridone compounds against Gram-positive (GmP) bacteria we term these compounds GmPcides, which hold promise in combating the rising tide of antibiotic resistant Gram-positive pathogens.


Asunto(s)
Bacterias Grampositivas , Piridonas , Enterococos Resistentes a la Vancomicina , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , N-Acetil Muramoil-L-Alanina Amidasa/farmacología , Piridonas/farmacología , Vancomicina/farmacología , Enterococos Resistentes a la Vancomicina/efectos de los fármacos
19.
J Am Chem Soc ; 144(25): 11306-11315, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35707951

RESUMEN

Mechanistic understanding and the control of molecular self-assembly at all hierarchical levels remain grand challenges in supramolecular chemistry. Functional realization of dynamic supramolecular materials especially requires programmed assembly at higher levels of molecular organization. Herein, we report an unprecedented molecular control on the fibrous network topology of supramolecular hydrogels and their resulting macroscopic properties by biasing assembly pathways of higher-order structures. The surface-catalyzed secondary nucleation process, a well-known mechanism in amyloid fibrilization and chiral crystallization of small molecules, is introduced as a non-covalent strategy to induce physical cross-links and bundling of supramolecular fibers, which influences the microstructure of gel networks and subsequent mechanical properties of hydrogels. In addition, seed-induced instantaneous gelation is realized in the kinetically controlled self-assembled system under this study, and more importantly, the extent of secondary nucleation events and network topology is manipulated by the concentration of seeds.


Asunto(s)
Hidrogeles , Cristalización , Hidrogeles/química
20.
West J Emerg Med ; 23(3): 312-317, 2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35679493

RESUMEN

INTRODUCTION: New evidence suggests that emergency department (ED)-based infectious diseases screening programs have utility. We aimed to compare clinic-based and ED-based hepatitis C virus (HCV) screening programs within a single health system, to identify key differences in HCV antibody (Ab) positivity and chronic HCV, as well as population demographics. METHODS: In the clinic-based program, adults in the birth cohort (born 1945-1965) were screened for HCV. In the ED-based program, non-targeted HCV screening of all adults was conducted. We included patients screened between June 2019-June 2020. Patients were screened for anti-HCV Ab, and positive results were followed by HCV viral load (VL) testing. Our primary outcomes were seroprevalence of HCV Ab and HCV VL. RESULTS: There were 1,296 and 12,778 patients screened for HCV in the clinics and the ED, respectively. In the clinic setting, 13 patients (1%) screened positive for HCV Ab and nine (69%) completed VL testing, which was positive in one patient (11%). In the ED, 1,053 patients (8%) screened positive for HCV Ab and 847 (80%) underwent reflex VL testing, which was positive in 381 patients (45%). In an ED birth cohort sub-analysis, Hepatitis C virus Ab seroprevalence was 15% (675/4521). CONCLUSION: In this study of patients in a single healthcare system, ED-based HCV screening was higher yield than clinic-based screening.


Asunto(s)
Hepacivirus , Hepatitis C , Adulto , Servicio de Urgencia en Hospital , Hepatitis C/diagnóstico , Hepatitis C/epidemiología , Anticuerpos contra la Hepatitis C , Humanos , Tamizaje Masivo/métodos , Estudios Seroepidemiológicos
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