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1.
Int J Food Microbiol ; 363: 109503, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-34968888

RESUMO

Staphylococcus argenteus has been recently established as a novel species of Staphylococcus aureus complex. It is known to cause various human diseases, such as skin and soft-tissue infections, sepsis, and staphylococcal food poisoning, although the source of infection has not been clearly described. In food poisoning cases, the source of bacterial contamination in food is unknown. This study examined the prevalence of S. argenteus among retail fresh food and poultry slaughterhouses in Japan. Among 642 food samples examined, successful isolation of S. argenteus was achieved in 21 of 151 (13.9%) chicken samples. No isolations from pork, beef, fish, or vegetables in retail markets were confirmed. Multiple-locus sequence typing revealed that the 21 isolates were classified into four sequence types (ST) that were divided into 14 subtypes using spa-typing. All food isolates were susceptible to methicillin and did not show positivity for the Panton-Valentine leukocidin gene. When bacteria were isolated from two poultry slaughterhouses in the same region, 14 S. argenteus strains were successfully isolated from only one slaughterhouse. Thirteen of 14 strains were isolated from a poultry carcass and slaughterhouse environments during a certain sampling period and were all classified as ST5961 with identical spa-type. Also, the number of single nucleotide variants (SNVs) detected on the core genomes of the same 13 strains were between 0 and 17, suggesting a long-term inhabitation of an S. argenteus strain inside the facility. Furthermore, one isolate from chicken meat was also genetically linked with the same lineage of slaughterhouse isolates, with ≤15 SNVs being detected. Additionally, one slaughterhouse isolate from chiller water and three chicken isolates were classified into the same cluster by phylogenetic analysis, although the number of pairwise SNVs ranged from 62 to 128. To the best of the authors' knowledge, this is the first study that demonstrated S. argenteus in a food processing facility and the possible bacterial contamination on food during food processing.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Matadouros , Animais , Antibacterianos , Bovinos , Humanos , Japão , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Filogenia , Staphylococcus/genética
2.
Org Lett ; 23(7): 2715-2719, 2021 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-33734719

RESUMO

Site-selective acylations of α-and ß-hydroxyamides in complex polyols are described. The combination of a pyridine aldoxime ester and Zn(OTf)2 facilitates the acylation of two types of N-glycolyl disaccharides, namely, Gal-GlcNGc and Neu5Gc-Gal, both of which are partial structures of polysaccharides responsible for biological actions, with highly site-selective modifications achieved. Furthermore, biotinylation, one of the most important techniques in chemical biology, is used to site-selectively acylate the ß-hydroxyl group in a glycopeptide.


Assuntos
Dissacarídeos/química , Glicopeptídeos/química , Polímeros/química , Polissacarídeos/química , Acilação , Dissacarídeos/síntese química , Ésteres/química , Glicopeptídeos/síntese química , Estrutura Molecular
3.
Org Lett ; 21(18): 7534-7538, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31498646

RESUMO

The site-selective acylations of ß-hydroxyamides in the presence of other hydroxyl groups are described. Central to the success of this modification is the metal-template-driven acylation using pyridine ketoxime esters as acylating reagents in combination with CuOTf. This strategy enables ß-hydroxyl groups to be site-selectively acylated in various derivatives, including sterically hindered secondary ß-alcohol. The utility of this methodology is showcased by the serine-selective modification of a glycopeptide with unprotected sugar.


Assuntos
Amidas/química , Ésteres/síntese química , Glicopeptídeos/química , Polímeros/química , Serina/química , Acilação , Amidas/síntese química , Esterificação , Ésteres/química , Estrutura Molecular , Estereoisomerismo
4.
Org Lett ; 20(11): 3367-3371, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29790765

RESUMO

Site-selective acylation of α-hydroxyl groups in amides has been achieved in the presence of other primary hydroxyl groups with intrinsic high reactivity. In this methodology, a relatively stable pyridine aldoxime ester was exploited as an acyl donor to suppress undesired acylation. The catalytic activation of a pyridine aldoxime ester with a Lewis acid produced a cationic complex, which preferentially attracted the Lewis basic α-hydroxyamide via a template effect, to thus facilitate o-acylation.

5.
Environ Sci Pollut Res Int ; 25(8): 7250-7261, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27005278

RESUMO

Our previous study showed that the sorption coefficient of certain polar pharmaceuticals to river sediment, especially particular amines, was unexpectedly high. Thus, we conducted sorption experiments of selected polar pharmaceuticals and pyrene derivatives, including amines, carboxylic acids, and neutral compounds, to model clay minerals, i.e., montmorillonite and kaolin, in addition to silica sands and humic substances. The contribution of each component was roughly estimated by simple fractionation of the individual sorption coefficients. Relatively high sorption coefficients (K d values) were found, especially for amines on clay minerals, which suggest that electrochemical affinity may play an important role. The estimated contribution percentage suggests a relatively large contribution from inorganic constituents, such as clay minerals, for silt loam soil; in contrast, organic components predominantly contribute for sandy river sediments. These findings could be the key to understanding not only the fate and transport but also bioavailability and environmental risks of pharmaceuticals, which are mostly polar and/or ionizable.


Assuntos
Bentonita/química , Substâncias Húmicas/análise , Minerais/química , Poluentes do Solo/análise , Solo/química , Adsorção , Disponibilidade Biológica , Argila , Sedimentos Geológicos , Rios
6.
World Neurosurg ; 103: 611-619, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28366753

RESUMO

BACKGROUND: Localization of the arteriovenous fistula (AVF) is a crucial step in the diagnosis and treatment of spinal vascular malformations (VMs). Noninvasive angiographic techniques such as dynamic magnetic resonance angiography and three-dimensional computed tomography angiography (CTA) have been used as standard modalities to localize AVF. With the increasing prevalence of high-specification computed tomography scanners, four-dimensional (4D) CTA is being increasingly used in the evaluation of cerebrovascular disorders. However, application of 4D-CTA in spinal lesions has been limited. The position and role of 4D-CTA, among various modalities, in the evaluation of spinal VMs has not been elucidated. METHODS: We retrospectively review our clinical experience with 4D-CTA used for spinal AVFs. 4D-CTA images were acquired in 10 cases of spinal VMs consisting of 8 dural/epidural AVFs and 2 perimedullary AVFs. Imaging findings of 4D-CTA and digital subtraction angiography were reviewed to validate the usefulness of 4D-CTA. RESULTS: In 9 of 10 cases, 4D-CTA accurately localized the AVF. The scan visualized direction of flow in the perimedullary veins in all cases. Regarding perimedullary AVFs, 4D-CTA showed dynamic images of feeding arteries, AVF, and perimedullary drainage. Information provided by 4D-CTA was beneficial as a reference in subsequent DSA. CONCLUSIONS: In the diagnostic process of spinal VMs, the position of 4D-CTA is the third choice for noninvasive angiography, after dynamic MRA and three-dimensional CTA. However, the role of 4D-CTA might be decisive in difficult-to-find spinal dural AVFs. We believe that this novel imaging technique can be applied in spinal VMs.


Assuntos
Fístula Arteriovenosa/diagnóstico por imagem , Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Doenças da Medula Espinal/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital , Fístula Arteriovenosa/cirurgia , Malformações Vasculares do Sistema Nervoso Central/cirurgia , Angiografia por Tomografia Computadorizada , Feminino , Tomografia Computadorizada Quadridimensional , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Doenças da Medula Espinal/cirurgia , Cirurgia Assistida por Computador
7.
J Reprod Dev ; 62(1): 59-64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26498203

RESUMO

Gene expression of epidermal growth factor (EGF), transforming growth factor-α (TGF-α) and EGF receptor (EGF-R) and the localization of the corresponding proteins in the canine testis were studied. Levels of mRNA expressions were determined by semiquantitative reverse transcription polymerase chain reaction in the testes of the peripubertal (4-6 months), young adult (3-4 years), advanced adult (7-8 years) and senescent (11-16 years) groups. The EGF-R mRNA level in the testes of the peripubertal group was significantly higher than those in the other groups, whereas there was no difference in EGF and TGF-α mRNA levels among groups. Immunohistochemical stainings for EGF, TGF-α and EGF-R in the testis revealed that immunoreactivity in the seminiferous epithelium and Sertoli cell was weak and nonspecific for the stage of spermatogenesis, and distinct staining was found in Leydig cells. These results suggest that the EGF family of growth factors may be involved in testicular maturation and function in the dog.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Células Intersticiais do Testículo/metabolismo , Epitélio Seminífero/metabolismo , Células de Sertoli/metabolismo , Testículo/metabolismo , Fator de Crescimento Transformador alfa/metabolismo , Animais , Peso Corporal , Cães , Regulação da Expressão Gênica , Imuno-Histoquímica , Masculino , RNA Mensageiro/metabolismo
8.
Neurosurg Rev ; 36(2): 289-96; discussion 296, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23196422

RESUMO

Time-resolved computed tomography angiography (4D-CTA) using a 320-row area detector CT scanner has recently been applied in the evaluation of cranial vascular disorders. However, application of 4D-CTA to spinal vascular disorder evaluation has never before been described. The authors herein report their initial experience of 4D-CTA in the evaluation of spinal arteriovenous fistulas (AVFs) and compare this novel modality with other imaging modalities. Four consecutive patients with spinal AVF underwent time-resolved contrast-enhanced magnetic resonance angiography (trMRA), 4D-CTA, and selective catheter angiography (CA). In 4D-CTA, volume data was transformed into 3D volume-rendered images and maximum intensity projection. These images were also evaluated by time-resolved serial phases. Then, images of each modality were compared, focusing on the detection of perimedullary draining veins and the prediction of AVF location and drainage flow direction. All modalities successfully detected perimedullary draining veins in all cases. Location of the AVF was detected in all cases by CA. trMRA and 4D-CTA detected the AVF in three out of the four cases. With regard to flow direction, while 4D-CTA successfully depicted ascending or descending drainage flow in the spinal canal, CA failed to detect the flow direction in one case while trMRA failed in two cases. In the case with epidural AVF, 4D-CTA was the only technique to detect the flow direction of perimedullary drainage. Although this is only an initial experience of the application of 4D-CTA to spinal vascular diseases, 4D-CTA was capable of detecting the dynamic vascular flow of spinal AVFs. The authors believe that 4D-CTA can be a useful option in the evaluation of spinal AVFs.


Assuntos
Fístula Arteriovenosa/diagnóstico , Angiografia Cerebral/métodos , Doenças da Coluna Vertebral/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Idoso , Catéteres , Angiografia Cerebral/efeitos adversos , Dura-Máter/patologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Medula Espinal/irrigação sanguínea , Medula Espinal/patologia , Tomografia Computadorizada por Raios X/efeitos adversos
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