Seroprevalence of SARS-CoV-2 antibodies in blood donors during the third wave of infection in Campeche Mexico.

At the end of 2020 and previous to the second wave of COVID-19 in Mexico, the seroprevalence in unvaccinated people in the state of Campeche, Mexico was below 15 %. The prevalence changes with ongoing pandemic and per geographical areas. Blood donors screening is a powerful and cost-effective alternative to monitor the population's infection exposure. The aim of the study was to estimate IgG anti-SARS-CoV-2 seropositivity in the Campeche's main blood bank in Mexico. This was a cross-sectional study carried out at the main blood bank of the State of Campeche, located in the Yucatan peninsula, Mexico for the period of August through September 2021 during the third wave of the epidemic. A blood sample from 479 blood donors were included in the study, the overall seropositivity for SARS-CoV-2 IgG antibodies was 69.1 %. Vaccinated donors represented 69.9 % versus 29.4 % unvaccinated. The seropositivity in unvaccinated represented 42.5 % and 81.17 % in vaccinated. The seroconversion in vaccinated donors after first shot was 79 % for Astra-Zeneca-vaccine and 90 % for Pfizer-vaccine. In conclusion 69.1 % of blood donors are seropositive for SARS-CoV-2 and 42.5 percent unvaccinated people are already also seropositive.

Congenital esophageal stenosis in a Labrador retriever.

A 1-year-old neutered male Labrador retriever was presented for investigation of chronic regurgitations that had started at weaning. Contrast radiographs and fluoroscopy of the thorax identified a focal narrowing of the proximal intrathoracic esophagus. Examination with CT-angiography excluded extraluminal causes for the narrowing, e.g., vascular ring anomaly. Esophagoscopy revealed the presence of a muscular stenosis with the appearance of a sphincter at the level of the proximal intrathoracic esophagus, without evidence of stricture. A diagnosis of congenital esophageal stenosis was made, suspected secondary to fibromuscular hypertrophy. Regurgitation resolved with conservative management and the dog was well at a 2-year follow-up examination. This case represents one of few small animal cases of congenital esophageal stenosis reported and apparently the only case successfully managed conservatively. Key clinical message: This report describes the clinical presentation, diagnostic imaging findings, and treatment of a rare case of congenital esophageal stenosis in a Labrador retriever. Medical and conservative therapies alone may be sufficient for treatment of congenital esophageal stenosis depending on presentation and suspected histopathological type. These therapies should be considered before initiating interventional procedures.

Sténose congénitale de l'oesophage chez un Labrador retriever. Un Labrador mâle castré âgé de 1 an a été présenté pour une investigation de régurgitations chroniques qui avaient commencé au sevrage. Les radiographies de contraste et la fluoroscopie du thorax ont identifié un rétrécissement focal de l'oesophage intrathoracique proximal. L'examen par tomodensitométrie-angiographie a exclu les causes extraluminales du rétrécissement, c'est-à-dire une anomalie de l'anneau vasculaire. L'oesophagoscopie a révélé la présence d'une sténose musculaire avec apparition d'un sphincter au niveau de l'oesophage intrathoracique proximal, sans signe de rétrécissement. Un diagnostic de sténose congénitale de l'oesophage a été posé, en raison d'une suspicion d'hypertrophie fibromusculaire. La régurgitation s'est résolue avec une gestion conservatrice et le chien allait bien lors d'un examen de suivi à 2 ans. Ce cas représente l'un des rares cas de sténose congénitale de l'oesophage rapportés chez les petits animaux et apparemment le seul cas traité avec succès de manière conservatrice.Message clinique clé :Ce rapport décrit la présentation clinique, les résultats de l'imagerie diagnostique et le traitement d'un cas rare de sténose congénitale de l'oesophage chez un Labrador. Les thérapies médicales et conservatrices seules peuvent être suffisantes pour le traitement de la sténose congénitale de l'oesophage en fonction de la présentation et du type histopathologique suspecté. Ces thérapies doivent être envisagées avant d'entreprendre des procédures interventionnelles.(Traduit par Dr Serge Messier).

Hotspot of Crimean-Congo Hemorrhagic Fever Virus Seropositivity in Wildlife, Northeastern Spain.

We conducted a serosurvey for Crimean-Congo hemorrhagic fever virus antibodies in various wildlife species in Catalonia, northeastern Spain. We detected high seroprevalence in southern Catalonia, close to the Ebro Delta wetland, a key stopover for birds migrating from Africa. Our findings could indicate that competent virus vectors are present in the region.

Synthesis, LC-MS/MS analysis, and biological evaluation of two vaccine candidates against ticks based on the antigenic P0 peptide from R. sanguineus linked to the p64K carrier protein from Neisseria meningitidis.

A peptide from the P0 acidic ribosomal protein (pP0) of ticks conjugated to keyhole limpet hemocyanin from Megathura crenulata has shown to be effective against different tick species when used in host vaccination. Turning this peptide into a commercial anti-tick vaccine will depend on finding the appropriate, technically and economically feasible way to present it to the host immune system. Two conjugates (p64K-Cys1pP0 and p64K-ßAla1pP0) were synthesized using the p64K carrier protein from Neisseria meningitidis produced in Escherichia coli, the same cross-linking reagent, and two analogues of pP0. The SDS-PAGE analysis of p64K-Cys1pP0 showed a heterogeneous conjugate compared to p64K-ßAla1pP0 that was detected as a protein band at 91kDa. The pP0/p64K ratio determined by MALDI-MS for p64K-Cys1pP0 ranged from 1 to 8, being 3-5 the predominant ratio, while in the case of p64K-ßAla1pP0 this ratio was 5-7. Cys1pP0 was partially linked to 35 out of 39 Lys residues and the N-terminal end, while ßAla1pP0 was mostly linked to the six free cysteine residues, to the N-terminal end, and, in a lesser extent, to Lys residues. The assignment of the conjugation sites and side reactions were based on the identification of type 2 peptides. Rabbit immunizations showed the best anti-pP0 titers and the highest efficacy against Rhipicephalus sanguineus ticks when the p64K-Cys1pP0 was used as vaccine antigen. The presence of high molecular mass aggregates observed in the SDS-PAGE analysis of p64K-Cys1pP0 could be responsible for a better immune response against pP0 and consequently for its better efficacy as an anti-tick vaccine. Graphical abstract.

Atypical retinal function in a mouse model of Fragile X syndrome.

Altered function of peripheral sensory neurons is an emerging mechanism for symptoms of autism spectrum disorders. Visual sensitivities are common in autism, but whether differences in the retina might underlie these sensitivities is not well-understood. We explored retinal function in the Fmr1 knockout model of Fragile X syndrome, focusing on a specific type of retinal neuron, the "sustained On alpha" retinal ganglion cell. We found that these cells exhibit changes in dendritic structure and dampened responses to light in the Fmr1 knockout. We show that decreased light sensitivity is due to increased inhibitory input and reduced E-I balance. The change in E-I balance supports maintenance of circuit excitability similar to what has been observed in cortex. These results show that loss of Fmr1 in the mouse retina affects sensory function of one retinal neuron type. Our findings suggest that the retina may be relevant for understanding visual function in Fragile X syndrome.

Efficacy of the Vaccine Candidate Based on the P0 Peptide against Dermacentor nitens and Ixodes ricinus Ticks.

The control of ticks through vaccination offers a sustainable alternative to the use of chemicals that cause contamination and the selection of resistant tick strains. However, only a limited number of anti-tick vaccines have reached commercial realization. In this sense, an antigen effective against different tick species is a desirable target for developing such vaccines. A peptide derived from the tick P0 protein (pP0) conjugated to a carrier protein has been demonstrated to be effective against the Rhipicephalus microplus, Rhipicephalus sanguineus, and Amblyomma mixtum tick species. The aim of this work was to assess the efficacy of this peptide when conjugated to the Bm86 protein against Dermacentor nitens and Ixodes ricinus ticks. An RNAi experiment using P0 dsRNA from I. ricinus showed a dramatic reduction in the feeding of injected female ticks on guinea pigs. In the follow-up vaccination experiments, rabbits were immunized with the pP0-Bm86 conjugate and challenged simultaneously with larvae, nymphs, and the adults of I. ricinus ticks. In the same way, horses were immunized with the pP0-Bm86 conjugate and challenged with D. nitens larva. The pP0-Bm86 conjugate showed efficacies of 63% and 55% against I. ricinus and D. nitens ticks, respectively. These results, combined with previous reports of efficacy for this conjugate, show the promising potential for its development as a broad-spectrum anti-tick vaccine.

The Association between Food Security Status and Psychological Distress and Loneliness among Full-Time Undergraduate Students at a Minority-Serving Institution.

Little is known about the relationship of food security (FS) status with mental health among students at minority-serving institutions. We aimed to elucidate the association of FS status with psychological distress and loneliness among full-time undergraduate students at a minority-serving institution. We used data from the National Collegiate Health Assessment III (n = 441). To assess FS, students responded to the USDA 6-item short form (range: 0-6) and responses were categorized as high (0), marginal (1) or low/very low (2-6) FS. The Kessler 6 scale assessed psychological distress (range: 0-24). The UCLA loneliness scale assessed loneliness (range: 3-9). Higher scores indicated higher psychological distress and loneliness. Using adjusted linear regression models, we examined the association of FS with psychological distress and loneliness. Compared to students with high FS (mean (SD): 9.4 (0.8)), students with marginal (11.4 (1.0); p < 0.05) or low/very low (11.8 (0.8); p < 0.01) FS had higher psychological distress scores. Compared to students with high FS (5.5 (0.3)), students with low/very low FS (6.0 (0.3); p < 0.05) had higher loneliness scores. Future studies should further explore these relationships using mixed methods, to provide complementary quantitative findings with the emic perspective of students and their experiences, which can inform programming to prevent and reduce food insecurity.

Characterization of two Cuban colonies of Rhipicephalus microplus ticks.

Rhipicephalus microplus (Canestrini, 1888) is one of the species with medical and economic relevance that has been reported in the list of Cuban tick species. Some morphological characterizations about the R. microplus species in Cuba have been published; however, molecular studies are lacking. Molecular phylogenetic analyses have grouped R. annulatus, R. australis and three clades of R. microplus in a complex named R. microplus. The present study aimed to characterize two R. microplus tick isolates, established as colonies at the Cuban National Laboratory of Parasitology. Morphological characterization of adult specimens was carried out by using Scanning Electron Microscopy. The sequences of mitochondrial genes: 12S rRNA, 16S rRNA and the subunit I of cytochrome c oxidase (coxI) and one nuclear sequence: internal transcribed spacer 2 (its2) were used for phylogenetic analyses. The life cycle under laboratory conditions for both isolates was also characterized. Tick specimens of both colonies showed morphological characteristics comparable with those distinctive for the R. microplus species. Phylogenies based on mitochondrial gene sequences identified congruently the Cuban tick colonies within the clade A of R. microplus. The life cycle of both isolates under laboratory conditions lasted 65 ± 5 days and the reproductive performance of female ticks of each colony also were similar with approximately 2500 larvae obtained from fully engorged female ticks. This study constitutes the first molecular characterization of ticks from the R. microplus species in Cuba.

A chemical conjugate of the tick P0 peptide is efficacious against Amblyomma mixtum.

After Rhipicephalus microplus, the most important tick species affecting livestock industry in Cuba belong to the Amblyomma genus. There are few reports of effective vaccine antigens for these species. Recently, vaccination and challenge trials using a peptide from the P0 acidic ribosomal protein of R. microplus ticks (pP0) as antigen have shown an efficacy around 90% against tick species from the Rhipicephalus genus. Given the high degree of sequence conservation among tick species, pP0 could be an antigen of versatile use in anti-tick vaccine formulations. In this paper, seven rabbits were immunized with a chemical conjugate of pP0 to keyhole limpet haemocyanin. Rabbits were challenged with an average of 1,900 Amblyomma mixtum larvae from a Cuban tick strain. The average number of recovered fed larvae and the viability of larvae in the moulting process were significantly lower in vaccinated animals compared with the control group. The overall vaccine efficacy of the P0 peptide antigen is 54% according to the calculated parameters.

Functional and Mass Spectrometric Evaluation of an Anti-Tick Antigen Based on the P0 Peptide Conjugated to Bm86 Protein.

A synthetic 20 amino acid peptide of the ribosomal protein P0 from ticks, when conjugated to keyhole limpet hemocyanin from Megathura crenulata and used as an immunogen against Rhipicephalus microplus and Rhipicephalus sanguineus s.l. species, has shown efficacies of around 90%. There is also experimental evidence of a high efficacy of this conjugate against Amblyomma mixtum and Ixodes ricinus species, which suggest that this antigen could be a good broad-spectrum anti-tick vaccine candidate. In this study, the P0 peptide (pP0) was chemically conjugated to Bm86 as a carrier protein. SDS-PAGE analysis of this conjugate demonstrated that it is highly heterogeneous in size, carrying from 1 to 18 molecules of pP0 per molecule of Bm86. Forty-nine out of the 54 lysine residues and the N-terminal end of Bm86 were found partially linked to pP0 by using LC-MS/MS analysis and the combination of four different softwares. Several post-translational modifications of Bm86 protein were also identified by mass spectrometry. High immunogenicity and efficacy were achieved when dogs and cattle were vaccinated with the pP0-Bm86 conjugate and challenged with R. sanguineus s.l. and R. microplus, respectively. These results encourage the development of this antigen with promising possibilities as an anti-tick vaccine.

Molecular, biological, and morphometric comparisons between different geographical populations of Rhipicephalus sanguineus sensu lato (Acari: Ixodidae).

In this study, different geographical populations of Rhipicephalus sanguineus sensu lato were compared by molecular, biological, and morphometric methods. Phylogenetic trees were constructed using 12S and 16S rDNA sequences and showed two distinct clades: one composed of ticks from Brazil (Jaboticabal, SP), Cuba (Havana) Thailand (Bangkok) and the so-called "tropical strain" ticks. The second clade was composed of ticks from Spain (Zaragoza), Argentina (Rafaela, Santa Fe) and the so-called "temperate strain" ticks. Morphometric analysis showed good separation between females of the two clades and within the temperate clade. Males also exhibited separation between the two clades, but with some overlap. Multiple biological parameters revealed differences between the two clades, especially the weight of the engorged female. These results confirm the existence of at least two species under the name "R. sanguineus".

Comparación de hidralazina y alfa metildopa en la hipertensión durante el embarazo / Comparison with hydralazyn and alfa metildopa in hypertension during pregnancy

Estudiamos 30 pacientes con pre-eclampsia severa, manejados 15 de ellos con metildopa y los otros 15 con Hidralazina, en el Hospital Materno Infantil San Lorenzo en Los Mina D. N. Nuestro trabajo ofrece evidencia de superioridad de la Hidrazalina sobre la metildopa, pues la respuesta hipotensora es algo más rápida y el medicamento produce menos efectos colaterales indeseables. Ambos medicamentos son efectivos en reducir la presión arterial