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1.
Clin Infect Dis ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39158989

RESUMEN

PURPOSE: To identify weather variables associated with pathogens contributing to infectious conjunctivitis globally. METHODS: Sample collection and pathogen identification from patients with acute infectious conjunctivitis was performed from 2017 to 2023. We linked pathogens identified from 13 sites across 8 countries with publicly available weather data by geographic coordinates. Mixed effects logistic regression analysis was performed to estimate the associations between temperature, precipitation, and relative humidity exposures, and the prevalence of infection types (RNA virus, DNA virus, bacteria, and fungus). RESULTS: 498 cases from the United States, India, Nepal, Thailand, Burkina Faso, Niger, Vietnam, and Israel were included in the analysis. 8-day average precipitation (mm) was associated with increased odds of RNA virus infection (odds ratio (OR)=1.47, 95% confidence interval (CI): 1.12 to 1.93, P=0.01) and decreased odds of DNA infection (OR=0.62, 95% CI: 0.46 to 0.82, P<0.001). Relative humidity (%) was associated with increased odds of RNA virus infections (OR=2.64, 95% CI: 1.51 to 4.61, P<0.001), and fungal infections (OR=2.35, 95% CI: 1.19 to 4.66, P=0.01), but decreased odds of DNA virus (OR=0.58, 95%CI: 0.37 to 0.90, P=0.02) and bacterial infections (OR=0.42, 95% CI: 0.25 to 0.71, P<0.001). Temperature (°C) was not associated with ocular infections for any pathogen type. CONCLUSIONS: This study suggests that weather factors affect pathogens differently. Particularly, humidity and precipitation were predictors for pathogens contributing to conjunctivitis worldwide. Additional work is needed to clarify the effects of shifts in weather and environmental factors on ocular infectious diseases.

3.
Am J Trop Med Hyg ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39013379

RESUMEN

Infectious keratitis is a leading cause of corneal blindness worldwide with little information known about causative etiologies in Malawi, Africa. This area is resource-limited with ophthalmologist and microbiology services. The Department of Ophthalmology at the Kamuzu College of Health Sciences in Blantyre, Malawi, is a participating site of an international corneal ulcer consortium, capriCORN (Comprehensive Analysis of Pathogens, Resistomes, and Inflammatory-markers in the CORNea). In this study, 50 patients with corneal ulcers were swabbed for pathogen identification using RNA-sequencing. Corneal trauma was reported in 41% and 19% of the patients worked in agriculture. A pathogen was identified in 58% of the cases. Fungal pathogens predominated, followed by viruses and bacteria. Aspergillus, Fusarium, HSV-1, and Gardnerella were the most common pathogens detected. 50% of patients reported treatment with an antibiotic before presentation. Pathogens unusual for infectious keratitis, such as Subramaniula asteroids, Aureobasidium pullulans, and Gardnerella vaginalis, were also detected.

4.
Int J Infect Dis ; 146: 107133, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38876162

RESUMEN

OBJECTIVES: To determine the associated pathogen during the 2023 conjunctivitis outbreak in Vietnam METHODS: RNA-sequencing was used to identify pathogens before and during the outbreak. RESULTS: 24 patients with infectious conjunctivitis between March and October 2023 from Hai Yen Vision Institute in Vietnam were swabbed. Coxsackievirus A24v was the most common pathogen identified. Phylogenetic analysis of these strains demonstrates similarities to the Coxsackievirus identified in the 2022 India outbreak. Human adenovirus D was also circulating. Ocular findings of tearing, purulence, and itching were common in this outbreak. CONCLUSIONS: Multiple viruses can co-circulate during conjunctivitis outbreaks. Hemorrhagic conjunctivitis, commonly associated with coxsackievirus conjunctivitis, was not a common clinical sign in this outbreak. Repeat genetic surveillance, with the notable inclusion of RNA virus detection strategies, is important for outbreak detection.


Asunto(s)
Infecciones por Coxsackievirus , Brotes de Enfermedades , Filogenia , Humanos , Vietnam/epidemiología , Infecciones por Coxsackievirus/epidemiología , Infecciones por Coxsackievirus/virología , Masculino , Femenino , Adulto , Persona de Mediana Edad , Adulto Joven , Niño , Adolescente , Preescolar , Conjuntivitis Viral/epidemiología , Conjuntivitis Viral/virología , Conjuntivitis Hemorrágica Aguda/epidemiología , Conjuntivitis Hemorrágica Aguda/virología
5.
Ear Nose Throat J ; : 1455613241255730, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38804662

RESUMEN

Background: The study aimed to identify data-driven body mass index (BMI) thresholds that are associated with varying risk of 30 day complications following adult tonsillectomy. Methods: The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was utilized to conduct a retrospective cohort analysis of patients undergoing adult tonsillectomy from 2005 to 2019. Stratum-specific likelihood ratio (SSLR) analysis was conducted to determine data-driven BMI strata that maximized the likelihood of 30 day complications following adult tonsillectomy. Patient demographics and clinical comorbidities were compared using chi-squared analysis and student t tests, where appropriate, for each stratum. Multivariable regression analysis was conducted to confirm association between identified data-driven strata with 30 day complication rates. Results: In total, 44,161 patients undergoing adult tonsillectomy were included in this study. SSLR analysis identified 2 BMI categories: 18 to 45 and 46+. Relative to the 18 to 45 BMI cohort, the 46+ BMI cohort was more likely to have 30 day all-cause complications after surgery [odds ratio (OR): 1.62, P = .007]. Specifically, the 46+ BMI cohort had significantly higher odds for 30 day major medical complications (OR: 2.86, P = .001), pulmonary domain complications (OR: 1.86, P = .041), unplanned reintubation (OR: 2.65, P = .033), and deep vein thrombosis (OR: 6.54, P = .026). Conclusions: We identified a BMI threshold of 46+ that was associated with a significantly increased risk of 30 day all-cause complications following adult tonsillectomy. These BMI strata can guide preoperative planning and risk-stratifying models for predicting 30 day complications in tonsillectomy surgery.

6.
Cornea ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771726

RESUMEN

PURPOSE: The purpose of this study was to identify conjunctival transcriptome differences in patients with Acanthamoeba keratitis compared with keratitis with no known associated pathogen. METHODS: The host conjunctival transcriptome of 9 patients with Acanthamoeba keratitis (AK) is compared with the host conjunctival transcriptome of 13 patients with pathogen-free keratitis. Culture and/or confocal confirmed Acanthamoeba in 8 of 9 participants with AK who underwent metagenomic RNA sequencing as the likely pathogen. Cultures were negative in all 13 cases where metagenomic RNA sequencing did not identify a pathogen. RESULTS: Transcriptome analysis identified 36 genes differently expressed between patients with AK and patients with presumed sterile, or pathogen-free, keratitis. Gene enrichment analysis revealed that some of these genes participate in several biologic pathways important for cellular signaling, ion transport and homeostasis, glucose transport, and mitochondrial metabolism. Notable relatively differentially expressed genes with potential relevance to Acanthamoeba infection included CPS1, SLC35B4, STEAP2, ATP2B2, NMNAT3, and AKAP12. CONCLUSIONS: This research suggests that the local transcriptome in Acanthamoeba keratitis may be sufficiently robust to be detected in the conjunctiva and that corneas infected with Acanthamoeba may be distinguished from the inflamed cornea where no pathogen was identified. Given the low sensitivity for corneal cultures, identification of differentially expressed genes may serve as a suggestive transcriptional signature allowing for a complementary diagnostic technique to identify this blinding parasite. Knowledge of differentially expressed genes may also direct investigation of disease pathophysiology and suggest novel pathways for therapeutic targets.

7.
Biomedicines ; 12(5)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38790986

RESUMEN

The poor prognosis for pancreatic ductal adenocarcinoma (PDAC) patients is due in part to the highly fibrotic nature of the tumors that impedes delivery of therapeutics, including nanoparticles (NPs). Our prior studies demonstrated that proglumide, a cholecystokinin receptor (CCKR) antagonist, reduced fibrosis pervading PanIN lesions in mice. Here, we further detail how the reduced fibrosis elicited by proglumide achieves the normalization of the desmoplastic tumor microenvironment (TME) and improves nanoparticle uptake. One week following the orthotopic injection of PDAC cells, mice were randomized to normal or proglumide-treated water for 3-6 weeks. Tumors were analyzed ex vivo for fibrosis, vascularity, stellate cell activation, vascular patency, and nanoparticle distribution. The histological staining and three-dimensional imaging of tumors each indicated a reduction in stromal collagen in proglumide-treated mice. Proglumide treatment increased tumor vascularity and decreased the activation of cancer-associated fibroblasts (CAFs). Additionally, PANC-1 cells with the shRNA-mediated knockdown of the CCK2 receptor showed an even greater reduction in collagen, indicating the CCK2 receptors on tumor cells contribute to the desmoplastic TME. Proglumide-mediated reduction in fibrosis also led to functional changes in the TME as evidenced by the enhanced intra-tumoral distribution of small (<12 nm) Rhodamine-loaded nanoparticles. The documented in vivo, tumor cell-intrinsic anti-fibrotic effects of CCK2R blockade in both an immunocompetent syngeneic murine PDAC model as well as a human PDAC xenograft model demonstrates that CCK2R antagonists, such as proglumide, can improve the delivery of nano-encapsulated therapeutics or imaging agents to pancreatic tumors.

8.
Am J Trop Med Hyg ; 109(6): 1333-1338, 2023 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-37931292

RESUMEN

Infectious conjunctivitis outbreaks remain a public health burden. This study focuses on the pathogen and antimicrobial resistance (AMR) profiles identified in Niger. Sixty-two patients with acute infectious conjunctivitis who presented to health posts were enrolled from December 2021 to May 2022. Nasal and conjunctival swabs were obtained from each patient. Unbiased RNA deep sequencing (RNA-seq) was used to identify associated pathogens. A pathogen was identified in 39 patients (63%; 95% CI, 50-74). Of those, an RNA virus was detected in 23 patients (59%; 95% CI, 43-73). RNA viruses were diverse and included human coronaviruses (HCoVs): SARS-CoV-2, HCoV-229E, HCoV-HKU1, and HCoV-OC43. A DNA virus was identified in 11 patients (28%; 95% CI, 17-44). Of those, four patients had a coinfection with an RNA virus and two patients had a coinfection with both an RNA virus and a bacterium. DNA viruses were predominantly human herpesvirus (cytomegalovirus, Epstein-Barr virus, human herpesvirus 8) and human adenovirus species B, C, and F. Eighteen patients (46%; 95% CI, 32-61) had a bacteria-associated infection that included Haemophilus influenza, Haemophilus aegyptius, Staphylococcus aureus, Streptococcus pneumoniae, and Moraxella spp. Antimicrobial resistance determinants were detected in either the conjunctiva or nasal samples of 20 patients (32%; 95% CI, 22-45) and were found to be more diverse in the nose (Shannon alpha diversity, 1.12 [95% CI, 1.05-1.26] versus 1.02 [95% CI, 1.00-1.05], P = 0.01). These results suggest the potential utility of leveraging RNA-seq to surveil pathogens and AMR for ocular infections.


Asunto(s)
Coinfección , Conjuntivitis , Infecciones por Virus de Epstein-Barr , Infecciones del Sistema Respiratorio , Humanos , Antibacterianos , Infecciones del Sistema Respiratorio/epidemiología , Niger/epidemiología , Farmacorresistencia Bacteriana , Herpesvirus Humano 4
9.
JAMA Ophthalmol ; 141(12): 1140-1144, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37917077

RESUMEN

Importance: Acute infectious conjunctivitis is a common ocular condition with major public health consequences. Objective: To assess regional variations and microbial etiologies of acute infectious conjunctivitis to guide treatment. Design, Setting, and Participants: In this cross-sectional study, patients with presumed acute infectious conjunctivitis were enrolled in the study at 5 sites (Honolulu, Hawaii; Los Angeles, San Francisco, and San Diego, California; and Petah-Tikva, Israel) from March 2021 to March 2023. Patients with allergic or toxic conjunctivitis were excluded. Main Outcomes and Measures: Pathogens were identified by unbiased RNA deep sequencing. Results: In all, 52 patients (mean [range] age, 48 [7-80] years; 31 females [60%]) were enrolled at 5 sites (6 patients from Honolulu, 9 from San Diego, 11 from Los Angeles, 13 from San Francisco, and 13 from Petah-Tikva). RNA deep sequencing detected human adenovirus species D in one-quarter of patients (13 of 52). A wide range of pathogens, including human coronavirus 229E, SARS-CoV-2, and herpes simplex virus type 1, was also identified, as well as several bacteria and fungi. Moreover, 62% (32 of 52) of patients presented with purulent discharge, while only 8% (4 of 52) of patients had confirmed bacterial pathogens. Conclusion and Relevance: In this cross-sectional study, pathogens associated with acute infectious conjunctivitis varied between all 5 sites in the US and Israel. Purulent discharge was a common presenting sign in this study, with a low specificity for bacteria-associated conjunctivitis, suggesting that further diagnostic workup may be necessary to inform antibiotic stewardship. Additional research on cost-effectiveness of using RNA deep sequencing is needed to ascertain whether it is better to monitor patients clinically until resolution of disease.


Asunto(s)
Conjuntivitis , Femenino , Humanos , Persona de Mediana Edad , Bacterias , Conjuntivitis/microbiología , Estudios Transversales , Enfermedad Aguda , Vigilancia en Salud Pública
10.
Cornea Open ; 2(2)2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37719281

RESUMEN

Purpose: To identify pathogens associated with the 2022 conjunctivitis outbreak in Tamil Nadu, India. Methods: This prospective study was conducted in November of 2022. Patients with presumed acute infectious conjunctivitis presenting to the Aravind Eye Clinic in Madurai, India were eligible. Anterior nares and conjunctival samples from participants were obtained and processed for metagenomic RNA deep sequencing (RNA-seq). Results: Samples from 29 patients were sequenced. A pathogen was identified in 28/29 (97%) patients. Coxsackievirus A24v, a highly infectious RNA virus, was the predominant pathogen and detected in 23/29 patients. Human adenovirus D (HAdV-D), a DNA virus commonly associated with conjunctivitis outbreaks, was detected in the remaining patients (5/29). Hemorrhagic conjunctiva was documented in both HAdV-D and coxsackievirus A24v affected patients but was not the predominant clinical presentation. Phylogenetic analysis of coxsackievirus A24v revealed a recent divergence from the 2015 outbreak. Conclusions: Coxsackievirus A24v and HAdV-D were co-circulating during the 2022 conjunctivitis outbreak in Tamil Nadu, India. Clinical findings were similar between patients with HAD-V and coxsackievirus A24v associated conjunctivitis. As high-throughput technologies become more readily accessible and cost-effective, unbiased pathogen surveillance may prove useful for outbreak surveillance and control.

11.
Int Health ; 2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37650684

RESUMEN

BACKGROUND: Infectious conjunctivitis is common in Nepal. MATERIALS AND METHODS: This prospective study recruited 60 patients with presumed acute infectious conjunctivitis from the B.P. Koirala Lions Center for Ophthalmic Studies in Kathmandu, Nepal. Swabs from the conjunctiva and anterior nares were processed for metagenomic RNA deep sequencing (RNA-seq). RESULTS: Pathogens were identified in 55% of cases. RNA viruses were the most common pathogen class identified. Severe acute respiratory syndrome coronavirus 2 was the most common RNA virus identified. CONCLUSIONS: Acute infectious conjunctivitis varies by location. Contrary to expectations, RNA viruses predominated. Repeat surveillance may be useful and RNA-seq allows for detection of the unexpected pathogen including RNA viruses.

12.
Optom Vis Sci ; 100(4): 276-280, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36880993

RESUMEN

SIGNIFICANCE: Acute infectious conjunctivitis poses significant challenges to eye care providers. It can be highly transmissible, and because etiology is often presumed, correct treatment and management can be difficult. This study uses unbiased deep sequencing to identify causative pathogens of infectious conjunctivitis, potentially allowing for improved approaches to diagnosis and management. PURPOSES: This study aimed to identify associated pathogens of acute infectious conjunctivitis in a single ambulatory eye care center. CASE REPORTS: This study included patients who presented to the University of California Berkeley eye center with signs and symptoms suggestive of infectious conjunctivitis. From December 2021 to July 2021, samples were collected from seven subjects (ages ranging from 18 to 38). Deep sequencing identified associated pathogens in five of seven samples, including human adenovirus D, Haemophilus influenzae , Chlamydia trachomatis , and human coronavirus 229E. CONCLUSIONS: Unbiased deep sequencing identified some unexpected pathogens in subjects with acute infectious conjunctivitis. Human adenovirus D was recovered from only one patient in this series. Although all samples were obtained during the COVID-19 pandemic, only one case of human coronavirus 229E and no SARS-CoV-2 were identified.


Asunto(s)
COVID-19 , Conjuntivitis , Humanos , Enfermedad Aguda , California/epidemiología , COVID-19/diagnóstico , COVID-19/epidemiología , Secuenciación de Nucleótidos de Alto Rendimiento , Pandemias
13.
Am J Trop Med Hyg ; 108(3): 595-598, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36646076

RESUMEN

The first manifestation of a viral infection may be conjunctivitis. There are limited data on the etiology of viral conjunctivitis in Vanuatu, a country in the South Pacific Ocean. Patients presenting to one of two Vanuatu health centers with presumed infectious conjunctivitis were eligible if symptom onset was within 14 days of screening. Conjunctival and anterior nasal swabs were obtained and subjected to unbiased RNA deep sequencing (RNA-seq) to identify DNA and RNA viruses. For samples collected from May to November 2021, RNA-seq identified a viral etiology in 12/48 patients. Human adenovirus species were the most common viruses (58%) detected, followed by human herpes viruses (cytomegalovirus, varicella zoster virus, and human herpes 7 virus). Rhinovirus C, Epstein-Barr virus, and bocavirus were also detected. In summary, the etiology for viral conjunctivitis in Vanuatu appears broad. Unbiased testing may be useful for disease surveillance.


Asunto(s)
Conjuntivitis Viral , Conjuntivitis , Infecciones por Virus de Epstein-Barr , Humanos , Vanuatu , Herpesvirus Humano 4 , Herpesvirus Humano 3/genética
14.
Cornea Open ; 2(4)2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38855500

RESUMEN

Purpose: Conjunctivitis epidemics and pandemics remain a global burden. This study aims to comprehensively identify pathogens associated with conjunctivitis in Vietnam. Methods: Patients with acute conjunctivitis presented to an outpatient clinic in Ho Chi Minh City, Vietnam, were enrolled from September 2022 to March 2023. Swabs were obtained from conjunctiva and anterior nares of all patients. Unbiased RNA deep sequencing (RNA-seq) was used to identify any replicating pathogens in the samples. Results: Samples from 35 patients were analyzed. A pathogen was identified in 80% of the patients. 72% (95% confidence interval: 54% to 85%) were infected with either HAdV-D or HAdV-B. RNA viruses detected were rhinoviruses and human coronavirus 229E. Bacteria etiologies included Streptococcus pneumoniae, Hemophilus influenza, and Pseudomonas spp. One patient had co-infection of rhinovirus A and HAdV-B. Vittaforma corneae, a fungus, was identified in one patient. Corneal sub-epithelial infiltrates, pseudomembranes, or pre-auricular lymphadenopathy were not reported in any patient. Conclusions: Human adenoviruses are the common circulating pathogens associated with infectious conjunctivitis in Vietnam. HAdV species, however, appear to vary between geographic locations within Vietnam. Other under-recognized pathogens identified in this study, such as RNA viruses, suggest broader pathogen surveillance may be beneficial.

15.
Work ; 73(3): 977-990, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36245350

RESUMEN

BACKGROUND: Musculoskeletal risks (MSRs) are a major concern among construction warehouse workers due to the lifting, carrying and lowering of heavy loads. OBJECTIVE: The objective of this study was to reduce MSRs among warehouse workers in the construction industry using virtual modelling and analysis of activities. METHODS: A preliminary study was carried out using the Standard Nordic Questionnaire. Biomechanical analysis, Ovako Working posture Assessment System (OWAS) and Rapid Upper Limb Assessment (RULA) were used to analyse the material handling activities. Virtual modelling was used develop the manikins with autoclaved aerated concrete (AAC) blocks at different carriage modes and stacking heights for the analysis. RESULTS: The preliminary study results revealed a higher prevalence of risk at their lower back (73.24%) among the construction warehouse workers. Biomechanical analysis showed a higher risk at L4-L5 joint of lumbar spine during overhead and bending postures for stacking the blocks. Posture analysis results of OWAS indicated a lower risk in overhead carriage mode. Detailed analysis with RULA confirms this result. Mean compressive force values at stacking heights were showed a significant difference (p < 0.05) in 8, 13, 18 and 21 kg AAC blocks. However, stacking height with a range of 120-140 cm was found as safer to the workers by considering all block sizes. CONCLUSION: An ergonomic intervention based on safer stacking heights was developed to reduce MSRs to an acceptable range. It improves productivity of handling the AAC blocks by reducing the cycle time. The intervention can be adapted for handling of similar materials in the construction industry.


Asunto(s)
Industria de la Construcción , Enfermedades Musculoesqueléticas , Sistema Musculoesquelético , Enfermedades Profesionales , Humanos , Ergonomía/métodos , Postura , Extremidad Superior , Enfermedades Musculoesqueléticas/etiología , Enfermedades Musculoesqueléticas/prevención & control , Enfermedades Musculoesqueléticas/epidemiología , Enfermedades Profesionales/epidemiología
16.
Sci Rep ; 12(1): 9159, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35650306

RESUMEN

Osteoarthritis (OA) is the most prevalent degenerative joint disease, resulting in joint pain, impaired movement, and structural changes. As the ability of joint tissue to resist stress is mainly imparted by fibrillar collagens in the extracellular matrix, changes in the composition and structure of collagen fibers contribute to the pathological remodeling observed in OA joints that includes cartilage degeneration, subchondral bone (SCB) sclerosis, and meniscal damage. Using the established OA model of destabilization of the medial meniscus (DMM) in C57BL/6J mice, we performed a comprehensive analysis of the content and structure of collagen fibers in the articular cartilage, subchondral bone, and menisci using complementary techniques, which included second harmonic generation microscopy and immunofluorescence staining. We found that regions exposed to increased mechanical stress in OA mice, typically closest to the site of injury, had increased collagen fiber thickness, dysregulated fiber formation, and tissue specific changes in collagen I and II (Col I and Col II) expression. In cartilage, OA was associated with decreased Col II expression in all regions, and increased Col I expression in the anterior and posterior regions. Col I fiber thickness was increased in all regions with disorganization in the center region. In the superficial SCB, all regions exhibited increased Col I expression and fiber thickness in OA mice; no changes were detected in the deeper regions of the subchondral bone except for increased Col I fiber thickness. In the menisci, OA led to increased Col I and Col II expression in the vascular and avascular regions of the anterior meniscus with increased Col I fiber thickness in these regions. Similar changes were observed only in the vascular region of the posterior meniscus. Our findings provide, for the first time, comprehensive insights into the microarchitectural changes of extracellular matrix in OA and serve as guidelines for studies investigating therapies that target collagenous changes as means to impede the progression of osteoarthritis.


Asunto(s)
Cartílago Articular , Osteoartritis , Animales , Cartílago Articular/patología , Colágeno , Matriz Extracelular/metabolismo , Ratones , Ratones Endogámicos C57BL , Osteoartritis/patología
17.
Anal Bioanal Chem ; 414(17): 4935-4951, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35579676

RESUMEN

A novel carbon dot (CD) was synthesized through the facile and simple hydrothermal method from Curcuma amada, as the precursor for the first time. These CDs with an average diameter of 4.6 nm display blue fluorescence, with excitation/emission maxima at 360/445 nm and a quantum yield of 14.1%. It exhibited high stability under different conditions and was characterized using various techniques. These CDs can be employed as a dual-sensing platform to detect tetracyclines and fluoroquinolones, two antibiotic classes. Even though antibiotics are regarded as an inevitable commodity, overuse and improper management of discarded antibiotics pose a severe threat to the environment. Herein, we developed a dual-sensing, biocompatible sensor with high selectivity and sensitivity to detect antibiotics. CD was employed as a fluorescence probe and detected tetracycline and fluoroquinolone antibiotic through inner filter effect-based fluorescence quenching and hydrogen bonding-based enhancement process, respectively. The linear range was 0-16 µM and the detection limit was 33 nM for tetracycline and 2 nM for fluoroquinolone antibiotic. As an electrochemical probe, CD selectively detected tetracycline with a lower detection limit of 0.5 nM over a linear range of 0-16 µM. Using both methods, a real sample analysis of the developed sensor exhibited accurate reliability and precision.


Asunto(s)
Puntos Cuánticos , Tetraciclinas , Antibacterianos , Biomasa , Carbono/química , Colorantes Fluorescentes/química , Fluoroquinolonas , Puntos Cuánticos/química , Reproducibilidad de los Resultados , Espectrometría de Fluorescencia/métodos , Tetraciclina , Tetraciclinas/análisis
18.
Environ Sci Pollut Res Int ; 29(35): 53225-53237, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35278183

RESUMEN

The photocatalytic activity of semiconducting silver carbonate was restricted by the lower stability and fast recombination rate of photogenerated electron-hole pairs. Sulfur-doped graphene oxide (SGO) is used as a cocatalyst for improving the photocatalytic activity of Ag2CO3 by reducing the recombination rate. A simple precipitation method was used for the modification of silver carbonate. The chemical, physical, optical, and electrochemical properties of the modified photocatalyst was characterized by XRD, SEM, TEM, UV-vis DRS, XPS, CV, impedance, and amperometry. The fabricated SGO-Ag2CO3 composite was successfully degraded various organic pollutants such as methylene blue (MB), rhodamine B(RhB), methyl orange (MO), tartrazine, and thiram with augmented mineralization. The optimization of weight percentage of the developed binary composite with 0.5% SGO-Ag2CO3 showed enhanced photocatalytic degradation and followed pseudo-first-order kinetics with rate constant 0.126. More than 90% of degradation efficiency of the pollutants within a short time promises the binary heterostructure for future industrial applications. The excellent stability and reproducibility of the composite opened a new route in the treatment of wastewater.


Asunto(s)
Contaminantes Ambientales , Grafito , Catálisis , Grafito/química , Luz , Reproducibilidad de los Resultados
19.
Matrix Biol ; 105: 127-143, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34995785

RESUMEN

Collagen cross-linking is an important step in optimal scar formation. Myocardial infarction (MI) results in loss of cardiomyocytes that are replaced with a scar (infarct) tissue. Disintegrin and metalloproteinases (ADAMs) are membrane-bound proteases that can interact with molecules intra- and extra-cellularly to mediate various cellular functions. ADAM15 is expressed in the myocardium, however its function in heart disease has been poorly explored. We utilized mice lacking ADAM15 (Adam15-/-) and wildtype (WT) mice. MI, induced by ligation of the left anterior descending artery, resulted in a transient but significant rise in ADAM15 protein in the WT myocardium at 3-days. Following MI, Adam15-/- mice exhibited markedly higher rate of left ventricular (LV) rupture compared to WT mice (66% vs. 15%, p<0.05). Echocardiography and strain analyses showed worsened LV dysfunction in Adam15-/- mice at 3days, prior to the onset of LV rupture. Second harmonic generation imaging revealed significant disarray and reduction in fibrillar collagen density in Adam15-/- compared to WT hearts. This was associated with lower insoluble and higher soluble collagen fractions, reduced cross-linking enzyme, lysyl oxidase-1 (LOX-1), and fibronectin which is required for LOX-1 function, in Adam15-/--MI hearts. Post-MI myocardial inflammation was comparable between the genotypes. In vitro, primary adult cardiac fibroblasts from Adam15-/- mice showed suppressed activation in response to ischemia (hypoxia+nutrient depletion) compared to WT fibroblasts. Adam15-deficiency was associated with reduced PAK1(p21-activated kinase-1) levels, a regulator of fibronectin and LOX-1 expression. In female mice, the rate of post-MI LV rupture, PAK1 signaling, LOX-1 and fibronectin protein levels were comparable between Adam15-/- and WT, indicating less impact of ADAM15 loss in females post- MI. This study reports a novel function for ADAM15 in collagen cross-linking and optimal scar formation post-MI which may also apply to scar formation in other tissues.


Asunto(s)
Cicatriz , Infarto del Miocardio , Proteínas ADAM/metabolismo , Animales , Cicatriz/genética , Cicatriz/patología , Colágeno/metabolismo , Femenino , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Infarto del Miocardio/genética , Infarto del Miocardio/metabolismo , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Remodelación Ventricular/genética
20.
J Fluoresc ; 32(2): 449-471, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35064386

RESUMEN

Carbon quantum dots (CQDs) have emerged as one of the most promising nanomaterials in the carbon nanostructures family in recent years due to their low toxicity, simple synthetic methods, unique fluorescence emission, good photostability, excellent water solubility, high specific surface areas and outstanding electronic properties. They have thus been employed in a wide range of applications, including fluorescent sensing, electrochemical sensing, bioimaging, drug delivery, antimicrobial studies, antioxidants, and photocatalysis. CQDs drawn great interest in sensing applications due to their unique photochemical, electrochemical and electrochemiluminescence properties. They exhibit excitation wavelength-dependent or -independent photoluminescence (PL) behaviour, high quantum yield, and promising binding ability with analytes, which make them an ideal candidate for use in PL based sensing platforms. Excessive use of agrochemicals in farm fields can pollute the environment and have potentially adverse health effects on aquatic and human life. Since there are very few monitoring techniques are available for sensing such harmful substances, there is an urgent need to develop a sensor for the facile, rapid and on-site detection and quantification of agrochemical residues in the environment. Several CQD-based fluorophores for detecting agrochemical residues employing static or dynamic quenching processes have recently been published. The key quenching mechanisms involved in the sensing process include FRET, PET and IFE. The first part of this review intends to provide a comprehensive overview of various techniques to characterize CQDs such as UV-vis., FT-IR, PL, XRD, NMR, TEM, TGA, XPS and Raman analysis. In addition application of CQDs as fluorescent sensors for agrochemical residue in different media are summarized in this reiew. The LOD values and rapid action of the sensor demonstrates significant advantages of these methods over conventional analytical procedures.


Asunto(s)
Agroquímicos/análisis , Carbono/química , Puntos Cuánticos/química , Colorantes Fluorescentes , Mediciones Luminiscentes , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Transmisión , Espectroscopía de Fotoelectrones , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Termogravimetría , Difracción de Rayos X
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