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1.
Vision Res ; 218: 108379, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38460402

RESUMO

Mutations in BEST1 cause an autosomal recessive disease in dogs where the earliest changes localize to the photoreceptor-RPE interface and show a retina-wide micro-detachment that is modulated by light exposure. The purpose of this study was to define the spatial and temporal details of the outer retina and its response to light with ultra-high resolution OCT across a range of ages and with different BEST1 mutations. Three retinal regions were selected in each eye: near the fovea-like area, near the optic nerve, both in the tapetal area, and inferior to the optic nerve in the non-tapetal area. The OS+ slab thickness was defined between the peak near the junction of inner and outer segments (IS/OS) and the transition between basal RPE, Bruch membrane, choriocapillaris and proximal tapetum (RPE/T). In wildtype (WT) dogs, two tapetal regions showed additional hyperscattering OCT peaks within the OS+ slab likely representing cone and rod outer segment tips (COST and ROST). The inferior non-tapetal region of WT dogs had only one of these peaks, likely ROST. In dogs with BEST1 mutations, all three locations showed a single peak, likely suggesting optical silence of COST. Light-dependent expansion of the micro-detachment by about 10 um was detectable in both tapetal and non-tapetal retina across all ages and BEST1 mutations.


Assuntos
Retina , Tomografia de Coerência Óptica , Cães , Animais , Células Fotorreceptoras Retinianas Cones , Visão Ocular
2.
J Food Sci ; 89(3): 1324-1336, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38317403

RESUMO

Isochoric freezing (IF) at -5°C/77 and -10°C/100 MPa was used to preserve carrot juice for 12 weeks. The juice qualities were compared to those using heat treatment (HT) at 95°C for 15 s followed by cold storage at 4°C. The native population of total aerobic bacteria, yeasts, and molds in isochoric frozen juice remained below the detection limit for 12 weeks. In comparison, microbes started to grow in heat-treated juices after 3 weeks of refrigeration. The color of isochoric frozen juice appeared more deep orange than the fresh juice due to an increase in carotenoid extractability. IF was not effective in reducing the activities of peroxidase, polyphenol oxidase, and pectin methyl esterase compared with HT. However, the isochoric samples showed higher carotenoid content, polyphenol content, and antioxidant capacity compared to the fresh and heat-treated juices. PRACTICAL APPLICATION: Isochoric freezing was used to produce carrot juice with extended shelf life. Isochoric freezing could be a beneficial alternative to conventional heat treatment for carrot juice processing as the applied pressures reached total inactivation levels of spoilage microorganisms. Moreover, the low processing temperatures better retained desirable compounds and quality attributes of fresh juice throughout its shelf life.


Assuntos
Daucus carota , Congelamento , Antioxidantes , Alimentos , Carotenoides
3.
Adv Sci (Weinh) ; 11(12): e2307256, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38233193

RESUMO

Atherosclerosis is initiated with endothelial cell (EC) dysfunction and vascular inflammation under hyperlipidemia. Sirtuin 3 (SIRT3) is a mitochondrial deacetylase. However, the specific role of endothelial SIRT3 during atherosclerosis remains poorly understood. The present study aims to study the role and mechanism of SIRT3 in EC function during atherosclerosis. Wild-type Sirt3f/f mice and endothelium-selective SIRT3 knockout Sirt3f/f; Cdh5Cre/+ (Sirt3EC-KO) mice are injected with adeno-associated virus (AAV) to overexpress PCSK9 and fed with high-cholesterol diet (HCD) for 12 weeks to induce atherosclerosis. Sirt3EC-KO mice exhibit increased atherosclerotic plaque formation, along with elevated macrophage infiltration, vascular inflammation, and reduced circulating L-arginine levels. In human ECs, SIRT3 inhibition resulted in heightened vascular inflammation, reduced nitric oxide (NO) production, increased reactive oxygen species (ROS), and diminished L-arginine levels. Silencing of SIRT3 results in hyperacetylation and deactivation of Argininosuccinate Synthase 1 (ASS1), a rate-limiting enzyme involved in L-arginine biosynthesis, and this effect is abolished in mutant ASS1. Furthermore, L-arginine supplementation attenuates enhanced plaque formation and vascular inflammation in Sirt3EC-KO mice. This study provides compelling evidence supporting the protective role of endothelial SIRT3 in atherosclerosis and also suggests a critical role of SIRT3-induced deacetylation of ASS1 by ECs for arginine synthesis.


Assuntos
Aterosclerose , Sirtuína 3 , Humanos , Camundongos , Animais , Pró-Proteína Convertase 9 , Argininossuccinato Sintase , Arginina , Endotélio , Inflamação
4.
Int J Mol Sci ; 25(2)2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38256083

RESUMO

Modern advances in disease genetics have uncovered numerous modifier genes that play a role in the severity of disease expression. One such class of genetic conditions is known as inherited retinal degenerations (IRDs), a collection of retinal degenerative disorders caused by mutations in over 300 genes. A single missense mutation (K42E) in the gene encoding the enzyme dehydrodolichyl diphosphate synthase (DHDDS), which is required for protein N-glycosylation in all cells and tissues, causes DHDDS-IRD (retinitis pigmentosa type 59 (RP59; OMIM #613861)). Apart from a retinal phenotype, however, DHDDS-IRD is surprisingly non-syndromic (i.e., without any systemic manifestations). To explore disease pathology, we selected five glycosylation-related genes for analysis that are suggested to have disease modifier variants. These genes encode glycosyltransferases (ALG6, ALG8), an ER resident protein (DDOST), a high-mannose oligosaccharyl transferase (MPDU1), and a protein N-glycosylation regulatory protein (TNKS). DNA samples from 11 confirmed DHDDS (K42E)-IRD patients were sequenced at the site of each candidate genetic modifier. Quantitative measures of retinal structure and function were performed across five decades of life by evaluating foveal photoreceptor thickness, visual acuity, foveal sensitivity, macular and extramacular rod sensitivity, and kinetic visual field extent. The ALG6 variant, (F304S), was correlated with greater macular cone disease severity and less peripheral rod disease severity. Thus, modifier gene polymorphisms may account for a significant portion of phenotypic variation observed in human genetic disease. However, the consequences of the polymorphisms may be counterintuitively complex in terms of rod and cone populations affected in different regions of the retina.


Assuntos
Alquil e Aril Transferases , Glucosiltransferases , Proteínas de Membrana , Degeneração Retiniana , Humanos , Genes Modificadores , Glucosiltransferases/genética , Proteínas de Membrana/genética , Mutação , Retina , Degeneração Retiniana/genética
5.
Int J Surg Pathol ; 32(1): 115-118, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37128815

RESUMO

Adamantinoma-like Ewing sarcoma (ALES) is a newly described rare entity, which shows EWSR1::FLI1 rearrangement characteristic of Ewing sarcoma. This can be diagnostically challenging as it manifests histologically with epithelial differentiation and has diffuse keratin expression as well as p40 and p60 positivity. We hereby report a case of ALES in a 33-year-old woman with a past medical history of breast carcinoma who presented with a right-sided parotid mass. CT scan of the neck showed a heterogenous mass within the superficial lobe, measuring 17 mm in diameter for which the patient underwent superficial parotidectomy. Histopathology of the mass revealed a malignant neoplasm formed of solid nests, cords and sheets of cells with minimal cytoplasm and monomorphic nuclei with granular chromatin and indistinct nucleoli. Brisk mitotic activity and tumor necrosis were also present. The tumor showed strong and diffuse reactivity for pankeratin (clone AE1/AE3) and keratin 20, both in a dot-like pattern, raising the suspicion of metastatic Merkel cell carcinoma; however, molecular studies showed EWSR1::FLI1 rearrangement, supporting the diagnosis of ALES. In summary, it is prudent to have knowledge about this entity to avoid its misdiagnosis as other malignancies of the head and neck region which exhibit a different clinical course, prognosis and hence treatment modalities.


Assuntos
Adamantinoma , Carcinoma de Célula de Merkel , Sarcoma de Ewing , Neoplasias Cutâneas , Feminino , Humanos , Adulto , Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/genética , Sarcoma de Ewing/patologia , Adamantinoma/diagnóstico , Adamantinoma/genética , Adamantinoma/cirurgia , Glândula Parótida/patologia , Carcinoma de Célula de Merkel/patologia , Neoplasias Cutâneas/patologia
6.
Microorganisms ; 11(10)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37894111

RESUMO

The gut microbiota, including bacteria, archaea, fungi, and viruses, compose a diverse mammalian gut environment and are highly associated with host health. Bacteriophages, the viruses that infect bacteria, are the primary members of the gastrointestinal virome, known as the phageome. However, our knowledge regarding the gut phageome remains poorly understood. In this review, the critical role of the gut phageome and its correlation with mammalian health were summarized. First, an overall profile of phages across the gastrointestinal tract and their dynamic roles in shaping the surrounding microorganisms was elucidated. Further, the impacts of the gut phageome on gastrointestinal fitness and the bacterial community were highlighted, together with the influence of diets on the gut phageome composition. Additionally, new reports on the role of the gut phageome in the association of mammalian health and diseases were reviewed. Finally, a comprehensive update regarding the advanced phage benchwork and contributions of phage-based therapy to prevent/treat mammalian diseases was provided. This study provides insights into the role and impact of the gut phagenome in gut environments closely related to mammal health and diseases. The findings provoke the potential applications of phage-based diagnosis and therapy in clinical and agricultural fields. Future research is needed to uncover the underlying mechanism of phage-bacterial interactions in gut environments and explore the maintenance of mammalian health via phage-regulated gut microbiota.

7.
Microbiol Spectr ; : e0022623, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37754684

RESUMO

Agricultural microbiomes are major reservoirs of antibiotic resistance genes (ARGs), posing continuous risks to human health. To understand the role of bacteriophages as vehicles for the horizontal transfer of ARGs in the agricultural microbiome, we investigated the diversity of bacterial and viral microbiota from fecal and environmental samples on an organic farm. The profiles of the microbiome indicated the highest abundance of Bacteroidetes, Firmicutes, and Proteobacteria phyla in animal feces, with varying Actinobacteria and Spirochaetes abundance across farm animals. The most predominant composition in environmental samples was the phylum Proteobacteria. Compared to the microbiome profiles, the trends in virome indicated much broader diversity with more specific signatures between the fecal and environmental samples. Overall, viruses belonging to the order Caudovirales were the most prevalent across the agricultural samples. Additionally, the similarities within and between fecal and environmental components of the agricultural environment based on ARG-associated bacteria alone were much lower than those of total microbiome composition. However, there were significant similarities in the profiles of ARG-associated viruses across the fecal and environmental components. Moreover, the predictive models of phage-bacterial interactions on bipartite ARG transfer networks indicated that phages belonging to the order Caudovirales, particularly in the Siphoviridae family, contained diverse ARG types in different samples. Their interaction with various bacterial hosts further implied the important role of bacteriophages in ARG transmission across bacterial populations. Our findings provided a novel insight into the potential mechanisms of phage-mediated ARG transmission and their correlation with resistome evolution in natural agricultural environments. IMPORTANCE Antibiotic resistance has become a serious health concern worldwide. The potential impact of viruses, bacteriophages in particular, on spreading antibiotic resistance genes is still controversial due to the complexity of bacteriophage-bacterial interactions within diverse environments. In this study, we determined the microbiome profiles and the potential antibiotic resistance gene (ARG) transfer between bacterial and viral populations in different agricultural samples using a high-resolution analysis of the metagenomes. The results of this study provide compelling genetic evidence for ARG transfer through bacteriophage-bacteria interactions, revealing the inherent risks associated with bacteriophage-mediated ARG transfer across the agricultural microbiome.

8.
Stem Cells Transl Med ; 12(9): 617-630, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37527504

RESUMO

This prospective cohort study aimed to assess long-term safety, dental implant survival, and clinical and radiological outcomes after maxillary sinus floor elevation (MSFE; lateral window technique) using freshly isolated autologous stromal vascular fraction (SVF) combined with calcium phosphate ceramics. All 10 patients previously participating in a phase I trial were included in a 10-year follow-up. They received either ß-tricalcium phosphate (ß-TCP; n = 5) or biphasic calcium phosphate (BCP; n = 5) with SVF-supplementation on one side (study). Bilaterally treated patients (6 of 10; 3 ß-TCP, 3 BCP) received only calcium phosphate on the opposite side (control). Clinical and radiological assessments were performed on 44 dental implants at 1-month pre-MSFE, and 0.5- to 10-year post-MSFE. Implants were placed 6 months post-MSFE. No adverse events or pathology was reported during a 10-year follow-up. Forty-three dental implants (98%) remained functional. Control and study sides showed similar peri-implant soft-tissue quality, sulcus bleeding index, probing depth, plaque index, keratinized mucosa width, as well as marginal bone loss (0-6 mm), graft height loss (0-6 mm), and graft volume reduction. Peri-implantitis was observed around 6 implants (control: 4; study: 2) in 3 patients. This study is the first to demonstrate the 10-year safety of SVF-supplementation in MSFE for jawbone reconstruction. SVF-supplementation showed enhanced bone regeneration in the short term (previous study) and led to no abnormalities clinically and radiologically in the long term.


Assuntos
Substitutos Ósseos , Implantes Dentários , Levantamento do Assoalho do Seio Maxilar , Humanos , Regeneração Óssea , Substitutos Ósseos/efeitos adversos , Fosfatos de Cálcio/efeitos adversos , Cerâmica , Estudos Prospectivos , Levantamento do Assoalho do Seio Maxilar/métodos , Fração Vascular Estromal , Ensaios Clínicos Fase I como Assunto , Seguimentos
9.
J Neurosci Methods ; 394: 109895, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37315846

RESUMO

BACKGROUND: Here, we present a semi-automated method for quantifying retinal ganglion cell (RGC) axon density at different distances from the optic nerve crush site using longitudinal, confocal microscopy images taken from whole-mounted optic nerves. This method employs the algorithm AxonQuantifier which operates on the freely available program, ImageJ. NEW METHOD: To validate this method, seven adult male Long Evans rats underwent optic nerve crush injury followed by in vivo treatment with electric fields of varying strengths for 30 days to produce optic nerves with a wide range of axon densities distal to the optic nerve crush site. Prior to euthanasia, RGC axons were labelled with intravitreal injections of cholera toxin B conjugated to Alexa Fluor 647. After dissection, optic nerves underwent tissue clearing, were whole-mounted, and imaged longitudinally using confocal microscopy. COMPARISON WITH EXISTING METHODS: Five masked raters quantified RGC axon density at 250, 500, 750, 1000, 1250, 1500, 1750, and 2000 µm distances past the optic nerve crush site for the seven optic nerves manually and using AxonQuantifier. Agreement between these methods was assessed using Bland-Altman plots and linear regression. Inter-rater agreement was assessed using the intra-class coefficient. RESULTS: Semi-automated quantification of RGC axon density demonstrated improved inter-rater agreement and reduced bias values as compared to manual quantification, while also increasing time efficiency 4-fold. Relative to manual quantification, AxonQuantifier tended to underestimate axon density. CONCLUSIONS: AxonQuantifier is a reliable and efficient method for quantifying axon density from whole mount optic nerves.


Assuntos
Traumatismos do Nervo Óptico , Nervo Óptico , Ratos , Animais , Masculino , Ratos Long-Evans , Axônios/fisiologia , Traumatismos do Nervo Óptico/terapia , Células Ganglionares da Retina/fisiologia , Regeneração Nervosa/fisiologia , Compressão Nervosa , Modelos Animais de Doenças
10.
Am J Ophthalmol Case Rep ; 32: 101873, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37388818

RESUMO

Purpose: An intravitreally injected antisense oligonucleotide, sepofarsen, was designed to modulate splicing within retinas of patients with severe vision loss due to deep intronic c.2991 + 1655A > G variant in the CEP290 gene. A previous report showed vision improvements following a single injection in one eye with unexpected durability lasting at least 15 months. The current study evaluated durability of efficacy beyond 15 months in the previously treated left eye. In addition, peak efficacy and durability were evaluated in the treatment-naive right eye, and re-injection of the left eye 4 years after the first injection. Observations: Visual function was evaluated with best corrected standard and low-luminance visual acuities, microperimetry, dark-adapted chromatic perimetry, and full-field sensitivity testing. Retinal structure was evaluated with OCT imaging. At the fovea, all visual function measures and IS/OS intensity of the OCT showed transient improvements peaking at 3-6 months, remaining better than baseline at ∼2 years, and returning to baseline by 3-4 years after each single injection. Conclusions and Importance: These results suggest that sepofarsen reinjection intervals may need to be longer than 2 years.

11.
Laryngoscope ; 133(11): 2999-3005, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37017269

RESUMO

OBJECTIVE: Determine the relationship between cognitive function and postoperative outcomes. METHODS: This IRB-approved retrospective cohort study included all patients treated between August 2015 and March 2020 undergoing major surgery for aerodigestive cancer or cutaneous/thyroid cancer that required free-flap reconstruction at Henry Ford Hospital. Routine administration of the Montreal Cognitive Assessment (MoCA) was completed as part of preoperative psychosocial evaluation. Outcomes included postoperative diagnosis of delirium, discharge disposition, return to the emergency department within 30 days of surgery, and readmission within 30 days of surgery. Univariate and multivariate logistic regression were used to determine the associations between preoperative MoCA score and each outcome measure. RESULTS: One hundred thirty-five patients with HNC were included in the study (mean [SD] age, 60.7 [±10.8] years; 70.4% [n = 95] male; 83.0% [n = 112] White, 16.3% [n = 22] Black). The average preoperative MoCA score was 23.4 (SD ± 4.5). Based on the MoCA score, 35% (n = 47) scored ≥26 (i.e., normal cognitive status), 55.6% (n = 75) scored between 18 and 25 (i.e., mild impairment), 8.1% (n = 11) scored between 10 and 17 (i.e., moderate impairment), and 1.5% (n = 2) scored <10 (i.e., severe impairment). After adjusting for other variables, a lower MoCA score was associated with discharge disposition to a location other than home and prolonged length of hospital stay. CONCLUSIONS: Preoperative cognitive function in patients undergoing major head and neck surgery for head and neck cancer was associated with discharge destination and length of stay. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:2999-3005, 2023.


Assuntos
Neoplasias de Cabeça e Pescoço , Procedimentos de Cirurgia Plástica , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Cognição , Neoplasias de Cabeça e Pescoço/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia
12.
Microorganisms ; 11(3)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36985115

RESUMO

Bacteriophages are viruses that infect bacteria and archaea and are classified as virulent or temperate phages based on their life cycles. A temperate phage, also known as a lysogenic phage, integrates its genomes into host bacterial chromosomes as a prophage. Previous studies have indicated that temperate phages are beneficial to their susceptible bacterial hosts by introducing additional genes to bacterial chromosomes, creating a mutually beneficial relationship. This article reviewed three primary ways temperate phages contribute to the bacterial pathogenicity of foodborne pathogens, including phage-mediated virulence gene transfer, antibiotic resistance gene mobilization, and biofilm formation. This study provides insights into mechanisms of phage-bacterium interactions in the context of foodborne pathogens and provokes new considerations for further research to avoid the potential of phage-mediated harmful gene transfer in agricultural environments.

13.
Transl Vis Sci Technol ; 12(1): 25, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36692456

RESUMO

Purpose: Blue cone monochromacy (BCM) is an X-linked retinopathy due to mutations in the OPN1LW/OPN1MW gene cluster. Symptoms include reduced visual acuity and disturbed color vision. We studied BCM color vision to determine outcome measures for future clinical trials. Methods: Patients with BCM and normal-vision participants were examined with Farnsworth-Munsell (FM) arrangement tests and the Color Assessment and Diagnosis (CAD) test. A retrospective case series in 36 patients with BCM (ages 6-70) was performed with the FM D-15 test. A subset of six patients also had Roth-28 Hue and CAD tests. Results: All patients with BCM had abnormal results for D-15, Roth-28, and CAD tests. With D-15, there was protan-deutan confusion and no bimodal tendency. Roth-28 results reinforced that finding. There was symmetry in color vision metrics between the two eyes and coherence between sessions with the arrangement tests and CAD. Severe abnormalities in red-green sensitivity with CAD were expected. Unexpected were different levels of yellow-blue results with two patterns of abnormal thresholds: moderate elevation in two younger patients and severe elevation in four patients ≥35 years. Coefficients of repeatability and intersession means were tabulated for all test modalities. Conclusions: Given understanding of advantages, disadvantages, and complexities of interpretation of results, both an arrangement test and CAD should be useful monitors of color vision through a clinical trial in BCM. Translational Relevance: Our pilot studies in BCM of arrangement and CAD tests indicated both were clinically feasible and interpretable in the context of this cone gene disease.


Assuntos
Defeitos da Visão Cromática , Visão de Cores , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Defeitos da Visão Cromática/diagnóstico , Defeitos da Visão Cromática/genética , Avaliação de Resultados em Cuidados de Saúde
14.
Clin Implant Dent Relat Res ; 25(1): 141-151, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36214357

RESUMO

OBJECTIVES: Mandibular retromolar (predominantly cortical) and maxillary tuberosity (predominantly cancellous) bone grafts are used in patients undergoing maxillary sinus floor elevation (MSFE) for dental implant placement. The aim of this retrospective cohort study was to investigate whether differences exist in bone formation and vascularization after grafting with either bone source in patients undergoing MSFE. METHODS: Fifteen patients undergoing MSFE were treated with retromolar (n = 9) or tuberosity (n = 6) bone grafts. Biopsies were taken 4 months postoperatively prior to dental implant placement, and histomorphometrically analyzed to quantify bone and osteoid area, number of total, apoptotic, and receptor activator of nuclear factor-κB ligand (RANKL)-positive osteocytes, small and large-sized blood vessels, and osteoclasts. The grafted area was divided in three regions (caudal-cranial): RI, RII, and RIII. RESULTS: Bone volume was 40% (RII, RIII) higher and osteoid volume 10% (RII) lower in retromolar compared to tuberosity-grafted areas. Total osteocyte number and number of RANKL-positive osteocytes were 23% (RII) and 90% (RI, RII) lower, but osteoclast number was higher (retromolar: 12, tuberosity: 0) in retromolar-grafted areas. The total number of blood vessels was 80% (RI) to 60% (RIII) lower, while the percentage of large-sized blood vessels was 86% (RI) to 25% (RIII) higher in retromolar-grafted areas. Number of osteocyte lacunae and apoptotic osteocytes were similar in both bone grafts used. CONCLUSIONS: Compared to the retromolar bone, tuberosity bone showed increased bone vitality and vascularization in patients undergoing MSFE, likely due to faster bone remodeling or earlier start of new bone formation. Therefore, tuberosity bone grafts might perform better in enhancing bone regeneration.


Assuntos
Implantes Dentários , Levantamento do Assoalho do Seio Maxilar , Humanos , Maxila/cirurgia , Maxila/patologia , Seio Maxilar/cirurgia , Estudos Retrospectivos , Transplante Ósseo , Implantação Dentária Endóssea
15.
Food Chem ; 402: 134161, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36126572

RESUMO

The almond industry suffers product losses caused by mold growth and toxin contamination. Gaseous chlorine dioxide (ClO2) has the potential for postharvest reduction of mycotoxic Aspergillus flavus. In this study, almonds inoculated with A. flavus were fumigated with gaseous ClO2 for 1, 2, 3, 8, 12, and 24 h using a dry precursor sachet batch method. The headspace concentration ranged from 0.5 to 2.4 mg/L, depending on initial dosing and time. At its highest concentration, gaseous ClO2 demonstrated an 84.4 % degradation efficiency of aflatoxin B1 (AFB1) with a reduction of 2.4 log CFU/g of A. flavus on almond kernels. Additionally, suppression of AFB1 continued after one-month storage at 4 °C. No significant oxidative effect and color difference (ΔE) was observed on the treated kernels. The almond industry can apply gaseous ClO2 technology to reduce mold contamination and product losses.


Assuntos
Aflatoxinas , Prunus dulcis , Aspergillus flavus/metabolismo , Aflatoxinas/metabolismo , Aflatoxina B1/metabolismo , Gases , Fumigação
16.
Front Microbiol ; 14: 1302032, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38318127

RESUMO

Introduction: Shiga toxin-producing Escherichia coli (STEC) O157:H7 is one of the notorious foodborne pathogens causing high mortality through the consumption of contaminated food items. The food safety risk from STEC pathogens could escalate when a group of bacterial cells aggregates to form a biofilm. Bacterial biofilm can diminish the effects of various antimicrobial interventions and enhance the pathogenicity of the pathogens. Therefore, there is an urgent need to have effective control measurements. Bacteriophages can kill the target bacterial cells through lytic infection, and some enzymes produced during the infection have the capability to penetrate the biofilm for mitigation compared to traditional interventions. This study aimed to characterize a new Escherichia phage vB_EcoS-UDF157lw (or UDF157lw) and determine its antimicrobial efficacy against E. coli O157:H7. Methods: Phage characterization included biological approaches, including phage morphology, one-step growth curve, stability tests (pH and temperature), and genomic approaches (whole-genome sequencing). Later, antimicrobial activity tests, including productive infection against susceptible bacterial strains, in vitro antimicrobial activity, and anti-biofilm, were conducted. Results: UDF157lw is a new member of the phages belonging to the Rogunavirus genus, comprising a long and non-contractile tail, isolated from bovine feces and shares close genomic evolutionary similarities with Escherichia phages vB_EcoS-BECP10 and bV_EcoS_AKS96. When used against E. coli O157:H7 (ATCC35150), phage UDF157lw exhibited a latent period of 14 min and a burst size of 110 PFU per infected cell. The phage remained viable in a wide range of pH values (pH 4-11) and temperatures (4-60°C). No virulence genes, such as stx, lysogenic genes, and antibiotic resistance genes, were found. Phage UDF157lw demonstrated high infection efficiencies against different E. coli O157:H7 and generic E. coli strains. In addition, UDF157lw encoded a unique major tail protein (ORF_26) with prominent depolymerase enzyme activity against various E. coli O157:H7 strains, causing large plaque sizes. In contrast to the phage without encoding depolymerase gene, UDF157lw was able to reduce the 24-h and 48-h E. coli O157:H7 biofilm after 1-h phage treatment. Discussion: The findings of this study provide insights into a new member of the Rogunavirus phages and demonstrate its antimicrobial potential against E. coli O157:H7 in vitro.

17.
Front Microbiol ; 13: 1054782, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36545205

RESUMO

Traditional foodborne pathogen detection methods are highly dependent on pre-treatment of samples and selective microbiological plating to reliably screen target microorganisms. Inherent limitations of conventional methods include longer turnaround time and high costs, use of bulky equipment, and the need for trained staff in centralized laboratory settings. Researchers have developed stable, reliable, sensitive, and selective, rapid foodborne pathogens detection assays to work around these limitations. Recent advances in rapid diagnostic technologies have shifted to on-site testing, which offers flexibility and ease-of-use, a significant improvement from traditional methods' rigid and cumbersome steps. This comprehensive review aims to thoroughly discuss the recent advances, applications, and limitations of portable and rapid biosensors for routinely encountered foodborne pathogens. It discusses the major differences between biosensing systems based on the molecular interactions of target analytes and biorecognition agents. Though detection limits and costs still need further improvement, reviewed technologies have high potential to assist the food industry in the on-site detection of biological hazards such as foodborne pathogens and toxins to maintain safe and healthy foods. Finally, this review offers targeted recommendations for future development and commercialization of diagnostic technologies specifically for emerging and re-emerging foodborne pathogens.

18.
Front Microbiol ; 13: 1053583, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439834

RESUMO

Seeds are one of the primary sources of contamination with foodborne pathogens, such as pathogenic Escherichia coli, and various Salmonella serovars, for produce, particularly sprouts. Due to the susceptibility of sprout growth to chemical-based antimicrobials and the rising issue of antimicrobial resistance, developing innovative antimicrobial interventions is an urgent need. Therefore, the objective of this study was to characterize Escherichia phage Sa157lw (or Sa157lw) for the biocontrol potential of Salmonella Typhimurium and E. coli O157:H7 on contaminated mung bean seeds. Phage Sa157lw was subjected to whole-genome sequencing and biological characterization, including morphology, one-step growth curve, and stress stability tests. Later, antimicrobial activity was determined in vitro and upon application on the mung bean seeds artificially contaminated with E. coli O157:H7 or Salmonella Typhimurium. Sa157lw possessed a contractile tail and belonged to the Kuttervirus genus under the Ackermannviridae family, sharing a close evolutionary relationship with E. coli phage ECML-4 and Kuttervirus ViI; however, tail spike genes (ORF_102 and ORF_104) were the primary region of difference. Comparative genomics showed that Sa157lw encoded a cluster of tail spike genes-including ORF_101, ORF_102, and ORF_104-sharing high amino acid similarity with the counterfeits of various Salmonella phages. Additionally, Sa157lw harbored a unique tail fiber (ORF_103), possibly related to the receptors binding of O157 strains. The genomic evidence accounted for the polyvalent effects of Sa157lw against E. coli O157:H7 and various Salmonella serovars (Typhimurium, Enteritidis, Agona, Saintpaul, and Heidelberg). Furthermore, the phage did not contain any virulence, antibiotic-resistant, or lysogenic genes. Sa157lw had a 30-min latent period on both E. coli O157:H7 and Salmonella Typhimurium, with an estimated burst size of 130 and 220 PFU/CFU, respectively, and was stable at a wide range of temperatures (4-60°C) and pH (pH4 to pH10). The phage application demonstrated a strong anti-E. coli O157:H7 and anti-Salmonella Typhimurium effects in 1.1 and 1.8 log reduction on the contaminated mung bean seeds after overnight storage at 22°C. These findings provide valuable insights into the polyvalent Sa157lw as a potential biocontrol agent of Salmonella Typhimurium and E. coli O157:H7 on sprout seeds.

19.
Ophthalmol Sci ; 2(2): 100133, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36249682

RESUMO

Purpose: To understand consequences of reconstituting cone photoreceptor function in congenital binocular blindness resulting from mutations in the centrosomal protein 290 (CEP290) gene. Design: Phase 1b/2 open-label, multicenter, multiple-dose, dose-escalation trial. Participants: A homogeneous subgroup of 5 participants with light perception (LP) vision at the time of enrollment (age range, 15-41 years) selected for detailed analyses. Medical histories of 4 participants were consistent with congenital binocular blindness, whereas 1 participant showed evidence of spatial vision in early life that was later lost. Intervention: Participants received a single intravitreal injection of sepofarsen (160 or 320 µg) into the study eye. Main Outcome Measures: Full-field stimulus testing (FST), visual acuity (VA), and transient pupillary light reflex (TPLR) were measured at baseline and for 3 months after the injection. Results: All 5 participants with LP vision demonstrated severely abnormal FST and TPLR findings. At baseline, FST threshold estimates were 0.81 and 1.0 log cd/m2 for control and study eyes, respectively. At 3 months, study eyes showed a large mean improvement of -1.75 log versus baseline (P < 0.001), whereas untreated control eyes were comparable with baseline. Blue minus red FST values were not different than 0 (P = 0.59), compatible with cone mediation of remnant vision. At baseline, TPLR response amplitude and latency estimates were 0.39 mm and 0.72 seconds, respectively, for control eyes, and 0.28 mm and 0.78 seconds, respectively, for study eyes. At 3 months, study eyes showed a mean improvement of 0.44 mm in amplitude and a mean acceleration of 0.29 seconds in latency versus baseline (P < 0.001), whereas control eyes showed no significant change versus baseline. Specialized tests performed in 1 participant confirmed and extended the standardized results from all 5 participants. Conclusions: By subjective and objective evidence, intravitreal sepofarsen provides improvement of light sensitivity for individuals with LP vision. However, translation of increased light sensitivity to improved spatial vision may occur preferentially in those with a history of visual experience during early neurodevelopment. Interventions for congenital lack of spatial vision in CEP290-associated Leber congenital amaurosis may lead to better results if performed before visual cortex maturity.

20.
iScience ; 25(10): 105274, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36274938

RESUMO

Signaling of vision to the brain starts with the retinal phototransduction cascade which converts visible light from the environment into chemical changes. Vision impairment results when mutations inactivate proteins of the phototransduction cascade. A severe monogenically inherited blindness, Leber congenital amaurosis (LCA), is caused by mutations in the GUCY2D gene, leading to a molecular defect in the production of cyclic GMP, the second messenger of phototransduction. We studied two patients with GUCY2D-LCA who were undergoing gene augmentation therapy. Both patients had large deficits in rod photoreceptor-based night vision before intervention. Within days of therapy, rod vision in both patients changed dramatically; improvements in visual function and functional vision in these hyper-responding patients reached more than 3 log10 units (1000-fold), nearing healthy rod vision. Quick activation of the complex molecular pathways from retinal photoreceptor to visual cortex and behavior is thus possible in patients even after being disabled and dormant for decades.

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