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Revealing interactions between ticks and wild animals is vital for gaining insights into the dynamics of tick-borne pathogens in the natural environment. We aimed to elucidate the factors that determine tick infestation in wild animals by investigating ticks on invasive raccoons (Procyon lotor) in Hokkaido, Japan. We first examined the composition, intensity, and seasonal variation of ticks infesting raccoons in six study areas in Hokkaido from March 2022 to August 2023. In one study area, ticks infesting tanukis (raccoon dog, Nyctereutes procyonoides albus) were collected in May to July in both 2022 and 2023, and questing ticks were collected from the vegetation by flagging every other week in the same period. Next, we screened 17 environmental and host variables to determine factors that affect the number of ticks infesting raccoons using generalized linear (mixed) models. From 245 raccoons, we identified a total of 3,917 ticks belonging to eight species of two genera: the most prominent species were Ixodes ovatus (52.9 %), followed by Haemaphysalis megaspinosa (14.4 %), Ixodes tanuki (10.6 %), and Ixodes persulcatus (9.5 %). Ixodes ovatus was also predominant among questing ticks and ticks infesting tanukis. Although I. tanuki was frequently collected from raccoons and tanukis, it was rarely collected in the field. The variables that significantly affected the infestation on raccoons differed by genus, species and developmental stage of the tick. For instance, the infestation of adult I. ovatus was significantly affected by four variables: night-time temperature during nine days before capturing the raccoon, the size of forest area around the capture site, sex of the raccoon, and sampling season. The first two variables were also responsible for the infestation on raccoons of almost all species and stages of ticks. Our study revealed that the number and composition of ticks infesting raccoons can be affected not only by landscape of their habitats but also by weather conditions in several days before capturing., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier GmbH.. All rights reserved.)

Abstract: Salmonella causes foodborne disease outbreaks worldwide and raises concerns about public health and economic losses. To determine prevalence, serovar, antimicrobial resistance patterns, and the presence of extended-spectrum β-lactamase (ESBL) genes in a cross-sectional study, 418 total samples from feces and carcasses (from three slaughterhouses) and pork and cutting boards (from four markets) were collected in a central Thailand province in 2017 and 2018. Of the 418 samples, 272 (65.1%) were positive for Salmonella. The prevalence of Salmonella-positive samples from markets (158 of 178; 88.8%) was significantly higher than that among samples from slaughterhouses (114 of 240; 47.5%) (P < 0.05). A total of 1,030 isolates were identified; 409 were assigned to 45 serovars, with Salmonella Rissen the most common (82 of 409; 20%). Two serovars, Salmonella Cannstatt and Salmonella Braubach, were identified for the first time in Thailand in market and slaughterhouse samples, respectively. Among 180 isolates representing 19 serovars, 133 (73.9%) exhibited multidrug resistance. Screening for ESBL production revealed that 41 (10.3%) of 399 isolates were ESBL positive. The prevalence of ESBL-producing Salmonella isolates was significantly higher among the market isolates (31 of 41; 75.6%) than among the slaughterhouse isolates in (10 of 41; 24.4%) (P < 0.05). In market samples, 24 (77.4%) of 31 isolates were recovered from pork and 7 (22.6%) were recovered from cutting boards. Nine ESBL-producing isolates carried single ESBL genes, either blaTEM (4 of 41 isolates; 9.8%) or blaCTX-M (5 of 41 isolates; 12.2%), whereas 11 (26.8%) carried both blaTEM and blaCTX-M. No ESBL-producing Salmonella isolate carried the blaSHV gene. These results suggest that pigs, their flesh, and cutting boards used for processing pork could be reservoirs for widespread ESBL-producing Salmonella isolates with multidrug resistance and outbreak potential across the food chain., (Copyright ©, International Association for Food Protection.)

Six subgroups of sporadic Creutzfeldt-Jakob disease have been identified by distinctive clinicopathologic features, genotype at polymorphic codon 129 [methionine (M)/valine (V)] of the PRNP gene, and type of abnormal prion proteins (type 1 or 2). In addition to the pure subgroups, mixed neuropathologic features and the coexistence of two types of abnormal prion proteins in the same patient also have been reported. Here, we found that a portion of the patients previously diagnosed as MM1 had neuropathologic characteristics of the MM2 thalamic form (ie, neuronal loss of the inferior olivary nucleus of the medulla). Furthermore, coexistence of biochemical features of the MM2 thalamic form also was confirmed in the identified cases. In addition, in transmission experiments using prion protein-humanized mice, the brain material from the identified case showed weak infectivity and generated characteristic abnormal prion proteins in the inoculated mice resembling those after inoculation with brain material of MM2 thalamic form. Taken together, these results show that the co-occurrence of MM1 and MM2 thalamic form is a novel entity of sporadic Creutzfeldt-Jakob disease prion strain co-occurrence. The present study raises the possibility that the co-occurrence of the MM2 thalamic form might have been overlooked so far because of the scarcity of abnormal prion protein accumulation and restricted neuropathology., (Copyright © 2019 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Localization of the abnormal and normal isoforms of prion proteins to detergent-resistant membrane microdomains, lipid rafts, is important for the conformational conversion. Lipid rafts are enriched in sialic acid-containing glycosphingolipids (namely, gangliosides). Alteration in the ganglioside composition of lipid rafts can affect the localization of lipid raft-associated proteins. To investigate the role of gangliosides in the pathogenesis of prion diseases, we performed intracerebral transmission study of a scrapie prion strain Chandler and a Gerstmann-Sträussler-Scheinker syndrome prion strain Fukuoka-1 using various knockout mouse strains ablated with ganglioside synthase gene (ie, GD2/GM2 synthase, GD3 synthase, or GM3 synthase). After challenge with the Chandler strain, GD2/GM2 synthase knockout mice showed 20% reduction of incubation time, reduced prion protein deposition in the brain with attenuated glial reactions, and reduced localization of prion proteins to lipid rafts. These results raise the possibility that the gangliosides may have an important role in prion disease pathogenesis by affecting the localization of prion proteins to lipid rafts., (Copyright © 2019 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Objectives: Tuberculosis (TB) caused by Mycobacterium tuberculosis (MTB) poses a major public health problem in Nepal. Although it has been reported as one of the dominant genotypes of MTB in Nepal, little information on the Central Asian Strain (CAS) family is available, especially isolates related to multidrug resistance (MDR) cases. This study aimed to elucidate the genetic and epidemiological characteristics of MDR CAS isolates in Nepal., Methods: A total of 145 MDR CAS isolates collected in Nepal from 2008 to 2013 were characterized by spoligotyping, mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR) analysis, and drug resistance-associated gene sequencing., Results: Spoligotyping analysis showed CAS1&#95;Delhi SIT26 as predominant (60/145, 41.4%). However, by combining spoligotyping and MIRU-VNTR typing, it was possible to successfully discriminate all 145 isolates into 116 different types including 18 clusters with 47 isolates (clustering rate 32.4%). About a half of these clustered isolates shared the same genetic and geographical characteristics with other isolates in each cluster, and some of them shared rare point mutations in rpoB that are thought to be associated with rifampicin resistance., Conclusions: Although the data obtained show little evidence that large outbreaks of MDR-TB caused by the CAS family have occurred in Nepal, they strongly suggest several MDR-MTB transmission cases., (Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

High morbidity and mortality associated with human cases of highly pathogenic avian influenza (HPAI) viruses, including H5N1 influenza virus, have been reported. The purpose of the present study was to evaluate the antiviral effects of peramivir against HPAI viruses. In neuraminidase (NA) inhibition and virus replication inhibition assays, peramivir showed strong inhibitory activity against H5N1, H7N1 and H7N7 HPAI viruses with sub-nanomolar activity in enzyme assays. In H5N1 viruses containing the NA H275Y mutation, the antiviral activity of peramivir against the variant was lower than that against the wild-type. Evaluation of the in vivo antiviral activity showed that a single intravenous treatment of peramivir (10 mg/kg) prevented lethality in mice infected with wild-type H5N1 virus and also following infection with H5N1 virus with the H275Y mutation after a 5 day administration of peramivir (30 mg/kg). Furthermore, mice injected with peramivir showed low viral titers and low levels of proinflammatory cytokines in the lungs. These results suggest that peramivir has therapeutic activity against HPAI viruses even if the virus harbors the NA H275Y mutation., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Pneumocystis jirovecii pneumonia (PCP) is classified as PCP with human immunodeficiency virus (HIV) and non-HIV PCP, and the two forms differ in progression and prognosis. Although early treatment is necessary, the diagnosis of non-HIV PCP is often difficult because of the underlying diseases. However, the outcome with treatment delay remains unclear because there are no concrete data indicating a worsened clinical situation or increased complications related to delayed therapy initiation. We retrospectively examined patients with non-HIV PCP admitted to Tokyo Women's Medical University Hospital from November 2008 to October 2010. The relationship between intubation with mechanical ventilation (within 1 week after starting treatment) and treatment delay was investigated. Treatment delay was defined as the period, in days, from onset to therapy initiation. In total, 24 confirmed non-HIV PCP cases were included. Median treatment delay was 7 ± 4.83 days (1-20 days). Twelve of 24 cases (50 %) were intubated, and 11 (45.8 %) died of their underlying diseases within 90 days. Treatment delay was more than 7 days in the intubation group, but was within 7 days in 9 of 12 nonintubation cases. The difference in treatment delay was significant (p = 0.0071) between the intubation and nonintubation groups, but there were no significant differences in survival rate at 90 days or other findings. We conclude that starting treatment within 7 days after onset is important because intubation and mechanical ventilation may be avoided in many cases.

The electrocatalytic reduction of nitrite to NO by CuMe(2)bpaCl(2), which is a model for the active site of copper-containing nitrite reductase, incorporated into collagen film was investigated. The 77-K EPR spectrum of CuMe(2)bpaCl(2) in the collagen matrix revealed the typical axial signals (g(//)=2.26, g( perpendicular)=2.05, A(//)=16.4mT) of a tetragonal Cu(2+) chromophore. The redox potential, which is related to the Cu(+)/Cu(2+) couple, was -63mV (E=72mV) at pH 5.5. In the presence of nitrite, an increase in the cathodic current was observed in the cyclic voltammogram of CuMe(2)bpaCl(2) in the collagen matrix. Upon reaching -300mV, a linear generation of NO was observed for the CuMe(2)bpaCl(2)/collagen film-coated electrode. The relationship between the rate of NO generation and the nitrite concentration in solution was analyzed using the Michaelis-Menten equation, where V(max)=3.16nM s(-1) and K(m)=1.1mM at pH 5.5. The current increase and the reaction rate were dependent on the pH of the solution. The mechanism of nitrite reduction by the copper complex in the collagen matrix was the same mechanism as that of the enzyme in aqueous solution., (2009 Elsevier B.V. All rights reserved.)

We investigated the protein pattern of a surgically resected tumour in a case where it was difficult to distinguish between duodenal and pancreatic cancer. The investigation was performed using two-dimensional polyacrylamide gel electrophoresis with silver staining. Samples of the duodenal tumour, normal duodenal mucosa and normal pancreatic tissue from the same patient were compared. Each gel had ca. 250-300 protein spots, and the tumour sample pattern more closely resembled that of normal duodenal mucosa than that of pancreatic tissue, suggesting that the tumour had arisen from duodenal mucosa. There were three proteins identified only in the tumour sample gel, and these may have been tumour-specific proteins.

Patterns of proteins of five surgically resected esophageal carcinomas were studied by two-dimensional polyacrylamide gel electrophoresis with silver staining. The samples of normal esophageal mucosa and esophageal carcinoma from the same patient were compared. Each gel had ca. 300 protein spots and had a similar pattern of proteins. Four spots were observed in all of the esophageal carcinomas that were not present in any of the normal mucosae. The molecular weights and isoelectric points were 46,000 and 5.3, 46,000 and 5.2, 36,000 and 4.7 and 33,000 and 5.1, respectively. One spot was observed in all of the normal mucosae but not in any of the esophageal carcinomas. Its molecular weight and isoelectric point were 27,000 and 5.3, respectively.