Search

The electrochemical quartz crystal nanobalance has been used to study the redox behavior of palladium phthalocyanine microcrystals attached to gold and platinum in aqueous solutions at different pH values. In order to investigate the substrate effect, paraffin impregnated graphite electrodes were also applied. It was found that the redox transformations of palladium phthalocyanine are accompanied with deprotonation-protonation as well as the sorption and desorption of counterions, respectively, the extent of which depends on the pH. Based on the results of the nanogravimetric measurements, a redox mechanism describing also the pH dependence is suggested. Simultaneously with the charge transfer processes, solid-solid phase transitions and water transport occur.

Domestic and wild felids are frequently parasitized by apicomplexan protozoa in the genus Cytauxzoon . Expanding species diversity has recently been described within this genus, with potential implications for epidemiology and pathogenesis. In light of these findings, this study assessed the genetic diversity of Cytauxzoon spp. in wild felids (n = 66) from different eco-regions of Brazil and Argentina. Of the 66 blood samples analyzed, 53 (80.3%) were 18S rRNA gene PCR-positive for Cytauxzoon spp., including 43 jaguars ( Panthera onca ) and 10 ocelots ( Leopardus pardalis ). Panthera onca specimens (100%, 43/43) were most frequently infected, followed by Leopardus pardalis (76.9%; 10/13). Cytauxzoon spp. were not detected in Leopardus braccatus (n = 1) or Puma concolor (n = 9). Phylogenetic analyses of fragments of the 18S rRNA, cytB , and cox-1 gene sequences from jaguars were closely related to Cytauxzoon felis . In contrast, sequences from ocelots were more closely associated with Cytauxzoon brasiliensis . Distance and haplotype analysis further confirmed the circulation of at least two distinct genovariants of C. felis among jaguars, as evidenced by their close positioning and low genetic divergence (0-0.14% for 18S rRNA, 0.37-0.56% for cytB , and 0.08-0.74% for cox-1 ). Additionally, sequence data from ocelots suggested that multiple genovariants of C. brasiliensis are circulating among these cats in different Brazilian eco-regions. Our study provides evidence of two distinct Cytauxzoon organisms parasitizing free-ranging and captive jaguars and ocelots, respectively, in Brazil and Argentina.

This study reinforces the value of a One Health approach to infectious disease outbreak investigations. After the onset of neuropsychiatric symptoms in their son, our investigation focused on a family composed of a mother, father, two daughters, the son, two dogs, and a rabbit, all with exposures to vectors (fleas and ticks), rescued dogs, and other animals. Between 2020 and 2022, all family members experienced illnesses that included neurological symptoms. Prolonged menorrhagia (130d) in the youngest daughter ultimately resolved following antibiotic administration. One dog was diagnosed with a splenic hematoma and months later spinal histiocytic sarcoma. The father, both daughters, and one dog were seroreactive to multiple Bartonella spp. antigens, whereas the mother and son were not seroreactive. Bartonella quintana DNA was amplified from specimens obtained from all family members. Based upon DNA sequencing, infection with B. quintana was confirmed for the mother and both pet dogs. Bartonella henselae DNA was amplified and sequenced from the youngest daughter, the son, and one dog (co-infected with B. quintana ), and from Ctenocephalides felis collected from their pet rabbit. All five family members and one dog were infected with Babesia divergens -like MO-1. Both parents were co-infected with Babesia microti. Droplet digital PCR supported potential infection with a Borrelia species in three family members. This study provided additional case-based evidence supporting the role of stealth Babesia , Bartonella , and Borrelia pathogens as a cause or cofactor in neurological and neuropsychiatric symptoms. We conclude that a One Health investigation approach, particularly for stealth vector borne pathogens such as Babesia , Bartonella , and Borrelia spp., will enhance clinical and epidemiological understanding of these organisms for animal and human health. During outbreak investigations it is critical to document travel and vector exposure histories, symptoms, and pathology in pets and human patients, contact with rescued, wild, or feral animals and perform diagnostic testing that includes family members, pets, and vectors.

More than one-hundred Babesia species that affect animals and humans have been described, eight of which have been associated with emerging and underdiagnosed zoonoses. Most diagnostic studies in humans have used serology or molecular assays based on the 18S rRNA gene. Because the 18S rRNA gene is highly conserved, obtaining an accurate diagnosis at the species level is difficult, particularly when the amplified DNA fragment is small. Also, due to its low copy number, sequencing of the product is often unsuccessful. In contrast, because the Babesia internal transcribed regions (ITS), between 18S rRNA and 5.8S rRNA, and between 5.8S rRNA and 28S rRNA, contain highly variable non-coding regions, the sequences in these regions provide a good option for developing molecular assays that facilitate differentiation at the species level. In this study, the complete ITS1 and ITS2 intergenic regions of different Piroplasmida species were sequenced to add to the existing GenBank database. Subsequently, ITS1 and ITS2 sequences were used to develop species-specific PCR assays and specific single-plex and multiplex conventional (c)PCR, quantitative real-time (q)PCR, and digital (d)PCR assays for four zoonotic Babesia species ( Babesia divergens , Babesia odocoilei , Babesia duncani , and Babesia microti ). The efficacy of the assay protocols was confirmed by testing DNA samples extracted from human blood or enrichment blood cultures. Primers were first designed based on the 18S rRNA-5.8S rRNA and 5.8S rRNA-28S rRNA regions to obtain the ITS1 and ITS2 sequences derived from different Piroplasmida species ( B. odocoilei , Babesia vulpes , Babesia canis , Babesia vogeli , Babesia gibsoni , Babesia lengau , Babesia divergens -like, B. duncani , B. microti , Babesia capreoli , Babesia negevi , Babesia conradae , Theileria bicornis , and Cytauxzoon felis ). Subsequently, using these sequences, single-plex or multiplex protocols were optimized targeting the ITS1 region of B. divergens , B. microti , and B. odocoilei . Each protocol proved to be sensitive and specific for the four targeted Babesia sp., detecting 10 -2 (for B. microti and B. odocoilei ) and 10 -1 (for B. divergens and B. duncani ) DNA copies per microliter. There was no cross-amplification among the Babesia species tested. Using 226 DNA extractions from blood or enrichment blood cultures obtained from 82 humans, B. divergens (seven individuals), B. odocoilei (seven individuals), and B. microti (two individuals) were detected and identified as a single infection, whereas co-infection with more than one Babesia sp. was documented by DNA sequencing in six (7.3%) additional individuals (representing a 26.8% overall prevalence). These newly developed protocols proved to be effective in detecting DNA of four Babesia species and facilitated documentation of co-infection with more than one Babesia sp. in the same individual.

Background: In recent years, Babesia and Bartonella species co-infections in patients with chronic, nonspecific illnesses have continued to challenge and change the collective medical understanding of "individual pathogen" vector-borne infectious disease dynamics, pathogenesis and epidemiology. The objective of this case series is to provide additional molecular documentation of Babesia odocoilei infection in humans in the Americas and to emphasize the potential for co-infection with a Bartonella species., Methods: The development of improved and more sensitive molecular diagnostic techniques, as confirmatory methods to assess active infection, has provided increasing clarity to the healthcare community., Results: Using a combination of different molecular diagnostic approaches, infection with Babesia odocoilei was confirmed in seven people suffering chronic non-specific symptoms, of whom six were co-infected with one or more Bartonella species., Conclusions: We conclude that infection with Babesia odocoilei is more frequent than previously documented and can occur in association with co-infection with Bartonella spp., (© 2024. The Author(s).)

Background: Feline-associated hemotropic Mycoplasma (hemoplasmas) are believed to be transmitted by two primary mechanisms: (1) direct transmission via fighting and (2) vector-borne transmission by the cat flea (Ctenocephalides felis). While the efficiency of transmission by C. felis appears low, most manuscripts focus on the prevalence of hemoplasmas in wild-caught fleas and report either a very low (< 3%) or a high (> 26%) prevalence. Therefore, we aimed to assess the influence of sample processing and PCR methods on C. felis hemoplasma infection prevalence., Methods: A systemic review of PubMed articles identified 13 manuscripts (1,531 fleas/flea pools) that met the inclusion criteria (performed PCR for >1 hemoplasma on C. felis collected from cats). Risk of bias was assessed utilizing the ROBINS-E tool. Meta-analysis performed in R of these manuscripts found that not washing samples and a common set of 16S rRNA primers first published in Jensen et al. 2001 were associated with increased hemoplasma prevalence. To evaluate the influence of washing on newly collected fleas, we assessed the hemoplasma status of 20 pools of 5 C. felis each, half of which were washed and half not washed., Results: Flea washing did not influence the detection of hemoplasma but instead amplified Spiroplasma. To assess non-specific amplification with the Jensen et al. 2001 primers, 67 C. felis samples (34% previously reported hemoplasma infected) were subject to PCR and sequencing. By this method, hemoplasma was detected in only 3% of samples. In the remaining "hemoplasma infected" fleas, PCR amplified Spiroplasma or other bacteria., Conclusions: Therefore, we concluded that hemoplasma infection in C. felis is rare, and future flea prevalence studies should sequence all positive amplicons to validate PCR specificity. Further investigation of alternative methods of feline-associated hemoplasma transmission and the ability of C. felis to maintain hemoplasma infection is necessary., (© 2024. The Author(s).)

Ctenocephalides felis, the cat flea, is among the most prevalent and widely dispersed vectors worldwide. Unfortunately, research on C. felis and associated pathogens (Bartonella and Rickettsia spp.) lags behind that of other vectors and vector-borne pathogens. Therefore, we aimed to review fundamental aspects of C. felis as a vector (behavior, epidemiology, phylogenetics, immunology, and microbiome composition) with an emphasis on key techniques and research avenues employed in other vector species. Future laboratory C. felis experimental infections with Bartonella, Rickettsia, and Wolbachia species/strains should examine the vector-pathogen interface utilizing contemporary visualization, transcriptomic, and gene-editing techniques. Further environmental sampling will inform the range and prevalence of C. felis and associated pathogens, improving the accuracy of vector and pathogen modeling to improve infection/infestation risk assessment and diagnostic recommendations., Competing Interests: Declaration of interests In conjunction with Sushama Sontakke and North Carolina State University, E.B.B. DVM holds US Patent No. 7,115,385: ‘Media and Methods for Cultivation of Microorganisms’, issued 3 October 2006. He is a co-founder, shareholder, and Chief Scientific Officer for Galaxy Diagnostics, a company that provides advanced diagnostic testing for the detection of Bartonella species infections as well as a scientific consultant to IDEXX Laboratories (Westbrook, ME, USA). All other authors declare no potential conflicts of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Rapid readmission (RR) of psychiatric patients within 30 days of discharge places a costly burden on state psychiatric facilities and may indicate suboptimal service provisions. Information regarding variables associated with RR of psychiatric patients is limited, particularly in Nevada. This study attempts to identify factors associated with RR at a Nevada state psychiatric hospital. Participants included 7177 patients admitted between May 2012 and April 2014. Using logistic regression, all admissions were reviewed and rapid readmits compared to counterparts who were not readmitted within 30 days. Nevada suffers from budget cuts in mental health care spending because of recent economic crisis and severe lack of bed space. This study demonstrates that it may be possible to reduce rates of costly RR by focusing on those with a history of RR and modifiable factors including social and financial support, as well as reliable and stable housing.