High-dimensional analysis of 16 SARS-CoV-2 vaccine combinations reveals lymphocyte signatures correlating with immunogenicity

The range of vaccines developed against severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) provides a unique opportunity to study immunization across different platforms. In a single-center cohort, we analyzed the humoral and cellular immune compartments following five coronavirus disease 2019 (COVID-19) vaccines spanning three technologies (adenoviral, mRNA and inactivated virus) administered in 16 combinations. For adenoviral and inactivated-virus vaccines, heterologous combinations were generally more immunogenic compared to homologous regimens. The mRNA vaccine as the second dose resulted in the strongest antibody response and induced the highest frequency of spike-binding memory B cells irrespective of the priming vaccine. Priming with the inactivated-virus vaccine increased the SARS-CoV-2-specific T cell response, whereas boosting did not. Distinct immune signatures were elicited by the different vaccine combinations, demonstrating that the immune response is shaped by the type of vaccines applied and the order in which they are delivered. These data provide a framework for improving future vaccine strategies against pathogens and cancer.

[A population-based study on seroprevalence and factors associated with SARS-CoV-2 infection in Córdoba, Argentina]

Seroepidemiological studies help identify the indirect distribution of diseases, detecting serological markers of immunity and demonstrating undiagnosed infections in the general population. The objectives were to estimate the seroprevalence of SARS-CoV-2 antibodies in Córdoba, Argentina, from December 2020 to January 2021 and to identify factors associated with the virus' contagiousness. A population-based cross-sectional observational study was performed in 3,225 individuals over two years of age living in Córdoba city, selected by multiple-stage random sampling proportional to distribution by gender, age group, and socioeconomic status in the city's population. Clinical characteristics, anthropometry, and comorbidities were collected by interview. Qualitative serological testing was performed for detection of SARS-CoV-2 nucleocapsid IgG antibodies (ARCHITECT, Abbott). SARS-CoV-2 seroprevalence was estimated for the total population and by age group, sex, socioeconomic status, and presence of target diseases. Prevalence ratios (PR) were estimated using a log-binomial regression model. SARS-CoV-2 seropositivity was 16.68% (95%CI: 15.41-18.01). Age 2 to 18 years, living in neighborhoods with low socioeconomic status, and obesity increased the odds of seropositivity (PR = 1.50; 95%CI: 1.10-2.04, PR = 1.91; 95%CI: 1.34-2.67 and PR = 1.39; 95%CI: 1.04-1.85). The results indicate that the city of Córdoba displays differential attributes that increase the likelihood of a positive SARS-CoV-2 antibody test. This allows targeting epidemiological surveillance strategies to reduce the spread of the virus.

Vacunación contra SARS-CoV-2 y su relación con enfermedad y muerte por COVID-19 en Argentina

Objetivo.

Conocer la efectividad de la vacunación contra SARS-CoV-2 para prevenir el desarrollo de enfermedad y muerte por COVID-19 en Córdoba, Argentina, en el periodo enero-junio de 2021.

Métodos.

Se llevó a cabo un estudio de cohorte retrospectivo en 1 139 458 residentes en la provincia de Córdoba. Se construyeron modelos de regresión logística múltiple que relacionaron la vacunación con la infección por SARS-CoV-2 o la muerte por COVID-19, considerando comorbilidades y factores de riesgo de enfermedades crónicas y ajustando por sexo y edad.

Resultados.

El haber recibido una o dos dosis de vacuna en la población general redujo el riesgo de enfermar un 98,8% y 99,3%, respectivamente; y de morir un 83% y 96,5%, respectivamente. En quienes contrajeron COVID-19, la probabilidad de morir se redujo en 57% y 80%, respectivamente. En cuanto a la probabilidad de muerte, el riesgo aumentó a medida que aumentaba la edad y con la pertenencia al sexo masculino o la presencia de obesidad, hipertensión arterial o diabetes mellitus.

Conclusión.

La vacunación es efectiva y protege contra la posibilidad de contraer COVID-19, desarrollar enfermedad grave o morir. Presentar obesidad, hipertensión arterial o diabetes mellitus, en orden decreciente, aumentan el riesgo de morir.

Efficacy and Safety of Sclerotherapy Using Polidocanol Foam: A Controlled Clinical Trial

OBJECTIVE

To assess the efficacy and safety of sclerotherapy performed with polidocanol foam compared to liquid polidocanol.

METHODS

Controlled clinical trial with 1 year follow up in which each patient acted as his/her own control. A total of 75 patients (six men and 69 women) with reticular or postoperative varices were enrolled and sclerotherapy was performed with liquid and with foam (Tessari method) using the same quantity of sclerosant for homogeneous varicose regions, to a total of 150 procedures. The sclerosant concentration was adjusted according to the vein diameter as assess by ultrasonography. The foam group was given 50% lower concentrations of sclerosant than liquid sclerosant group. Clinical assessment (pain, inflammation, pigmentation) and ultrasound examination (diameter of the lumen and length of sclerosed vein) were carried out at 15, 30, 90, and 365 days.

RESULTS

Foam allowed complete sclerosis at 90 days in 94.4% of patients compared with 53% for liquid (p<.001) and also allowed a more extensive venous sclerosis (10.1cm compared with 7.2 cm; p<.001). Pain, signs of inflammation, and pigmentation appeared more often with foam sclerosis, with significant difference. The degree of satisfaction was similar for both techniques.

CONCLUSIONS

Efficacy of venous sclerosis with foam seems to be greater than with liquid although there is a higher risk of minor secondary effects.

[Intravenous multi vitamin formulation to use in pediatric total parenteral nutrition]

BACKGROUND

No intravenous multivitamin formulation is available at the Chilean market that fulfills the requirements of pediatric patients on total parenteral nutrition. Therefore, adult formulations must be used.

AIM

To prepare a parenteral aqueous multivitamin solution, to be used in pediatric patients.

MATERIAL AND METHODS

The solution was prepared, mixing vitamins according to their stability and compatibility, in a horizontal laminar flow hood. The quality control for this formulation at times zero and 30 days consisted of an organoleptic analysis, microbiologic and pyrogen controls and vitamin quantification. In addition, the effect of vitamin solution incorporation on the stability of total parenteral nutrition formulae was evaluated. The approximated production cost was calculated.

RESULTS

The ampoules did not show changes on the organoleptic characteristics. No bacterial contamination or pyrogens were detected. Total parenteral nutrition solutions were not modified after the incorporation of the vitamins. The vitamin solution was stable for one month at 4 degrees C.

CONCLUSIONS

The manufacture of this formulation results in significant savings, because it has a low manufacturing cost and fulfills pediatric requirements.

Prenatal malnutrition-induced functional alterations in callosal connections and in interhemispheric asymmetry in rats are prevented by reduction of noradrenaline synthesis during gestation

Prenatal malnutrition results in increased concentration and release of central noradrenaline, a neurotransmitter that is an important regulator of normal regressive events such as axonal pruning and synaptic elimination. This suggests that some of the functional disturbances in brain induced by prenatal malnutrition could be due at least in part to increased noradrenaline activity that may enhance regressive events during early stages of development. To test this hypothesis we studied whether chronic administration of alpha-methyl-p-tyrosine, an inhibitor of tyrosine hydroxylase, to rats during gestation might prevent long-term deleterious effects of prenatal malnutrition on functional properties of interhemispheric connections of the visual cortex, and on asymmetry of visual evoked responses. The experiments were conducted on normal and malnourished rats 45-50 d of age. Prenatal malnutrition was induced by restricting the food consumption of pregnant rats to 40%, from d 8 postconception to parturition. At birth, prenatally malnourished rats had significantly greater whole-brain noradrenaline concentration as well as significantly enhanced noradrenaline release in the visual cortex. At 45-50 d of age, the malnourished group had a significantly smaller cortical area, exhibiting transcallosal evoked responses; in addition, the amplitude of these responses was significantly smaller. Malnourished rats showed a significant reduction of the normal interhemispheric asymmetry of visual evoked responses. The addition of 0.3% alpha-methyl-p-tyrosine to the diet of malnourished pregnant rats during the last 2 wk of gestation prevented functional disorders induced in the offspring by prenatal malnutrition on interhemispheric connectivity of visual areas and on interhemispheric bioelectrical asymmetry, probably by reducing the elevated brain noradrenaline activity and thereby restoring the normal trophic role of this neurotransmitter.

Recognition of an immunogenetically selected Trypanosoma cruzi antigen by seropositive chagasic human sera

If the H-2 congenic mouse strains A.SW (H-2n) and A.CA (H-2f), are infected with Trypanosoma cruzi, a 45 kDa protein (Tc45), present in cultured epimastigotes and blood trypomastigotes, is recognized only by the A.SW strain sera. In order to explore the possibility that among seropositive humans the response to Tc45 is also highly variable, 81 chagasic human sera (as defined by the HemAve agglutination test, Polychaco S.A.I.C., Buenos Aires, Argentina) were tested in a direct (epimastigote antigenic complex directly bound to the solid phase) and indirect immunoradiometric assay (IRMA) (Tc45, from a partially purified preparation, bound to the solid phase, by means of a monoclonal antibody). Sixty nine of these sera reacted in both the direct and indirect assays, 11 were negative in both assays (these samples may correspond to false positives detected by the commercial agglutination test) and only one reacted with the antigenic complex but not with Tc45. Reactivity of the human sera with the epimastigote antigenic extract was relatively homogenous, while reactivity with Tc45 was extremely variable. No statistical correlation was determined between the two variables. Given the high variability of the human response to Tc45, ranging from negative to highly positive, together with the immunogenetic restriction previously described in the murine model, we speculate that human MHC may also modulate the response to this molecule.

Immune depression induced by protein calorie malnutrition can be suppressed by lesioning central noradrenaline systems

Depressed immune function is well documented in protein calorie malnutrition (PCM). Also, central noradrenergic hyperactivity has recently been reported in malnourished animals. Increase in central noradrenaline activity could be responsible for cell-mediated immune depression. The present study is designed to address this hypothesis by testing whether neurotoxic lesion of central noradrenergic systems by 6-hydroxydopamine (6-OHDA) could improve lymphoproliferative response to mitogens and interleukin (IL)-1 production in PCM rats. A significant enhancement of lymphoproliferative response to concanavalin A (ConA) and in IL-1 production was observed in spleen mononuclear cells of PCM rats injected intracerebroventricularly with 120 micrograms of 6-OHDA, as compared with solvent injected and untreated PCM animals. A significant decrease in brain noradrenaline levels was produced in the drug-injected animals. These results suggest that central noradrenergic hyperactivity is one of the mechanisms involved in the immunodepression produced by malnutrition.

Depressed immune response in malnourished rats correlates with increased thymic noradrenaline level

Depressed immune response is well documented in protein-calorie malnutrition (PCM). Also, central and peripheral noradrenaline (NA) activities have been reported to be increased in malnourished animals. Since increases in central and peripheral NA may inhibit immune function, it is possible that malnutrition-induced immunodepression could be mediated by noradrenergic hyperactivity. To address this hypothesis the effect of malnutrition on cell-mediated immune response, as well as on NA levels of the median eminence, spleen and thymus was studied in PCM rats. Decreased lymphoproliferative response and IL-1 production by mononuclear macrophages was observed in PCM. Besides, increased NA concentration was detected in thymuses of PCM rats, while unchanged levels of this neurotransmitter were observed in median eminence and spleen. These data suggest a positive correlation between malnutrition-induced immunodepression and sympathetic noradrenergic activity in thymus, an organ implicated in immune cell differentiation during early development.

Clonidine treatment during gestation prevents functional deficits induced by prenatal malnutrition in the rat visual cortex

It has been shown that prenatal malnutrition results at birth in increased concentration of noradrenaline (NA) in the brain. Besides, it is known that NA is an important regulator of normal regressive processes occurring during synaptogenesis such as cell death, axonal pruning and synaptic elimination. The present study was designed to investigate (i) whether prenatal malnutrition enhances the NA release in the visual cortex and (ii) whether or not chronic administration of clonidine during gestation may prevent long-term deleterious effects of fetal malnutrition on functional properties of interhemispheric connections of the visual cortex and on the interhemispheric asymmetry of visual evoked responses. Prenatal malnutrition was induced by restricting food consumption to pregnant rats from Day 8 postconception to parturition. Results show that at birth, prenatally malnourished rats had higher NA release than normals. At 45-50 days of age, the malnourished group exhibited (a) reduced peak-to-peak amplitude and diminished extent of the projecting field of transcallosal evoked responses, and (b) abolished interhemispheric asymmetry of visual evoked responses. Clonidine administration to malnourished mothers from Day 14 postconception to parturition (10 g/kg/day s.c.), prevented in the offspring disorders induced by prenatal malnutrition on cortical NA release, on interhemispheric connectivity of visual areas and on interhemispheric bioelectrical asymmetry, probably by restoring the normal trophic role of NA during synaptogenesis. Results are discussed in relationship to normal regressive events occurring during early brain development.

Comparative effects of rose hip and corn oils on biliary and plasma lipids in rats

The comparative effects of dietary level and time of feeding corn (CO) and rose hip (RHO) oils on bile and plasma lipid composition were studied. 48 males Sprague Dawley rats were divided in two groups fed semipurified diets containing CO or RHO as the only lipid source. Groups of 6 rats were fed ad libitum diets containing 5% or 15% vegetable oil during 15 or 60 days. Food intake was not dependent on the type of oil, and was higher in 15% oil diets (p < 0.01), increasing with time of feeding (p < 0.001). Bile flow was similar in all groups. Biliary concentrations of cholesterol, phospholipids and bile acids were affected by the time of feeding (p < 0.001). Plasma total and high density lipoprotein (HDL) cholesterol levels were higher in 15% oil fed rats (p < 0.05). Triglycerides concentrations were similar in all groups. The results indicate that oil concentration and time of feeding were the most important variables affecting the lipid composition of rats, independently of the fatty acid composition of the ingested fats.

Functional alterations induced by prenatal malnutrition in callosal connections and interhemispheric asymmetry as revealed by transcallosal and visual evoked responses in the rat

It is known that nutritional restriction during gestation affects the growth of the corpus callosum. The present study was designed to evaluate whether prenatal malnutrition may alter, in the rat, the normal pattern of functional callosal interhemispheric connections of the visual cortex. Since callosal development has been associated with brain lateralization, the effect of malnutrition during gestation on the normal asymmetry of visual cortical evoked responses was also studied. Prenatal malnutrition was induced by restricting food consumption by pregnant rats (10 g daily) from Day 8 post-conception to parturition. Results of experiments performed on 45- to 50-day-old offspring showed that the starvation treatment (i) reduced both the peak-to-peak amplitude and the extent of the projecting field of transcallosal evoked responses, and (ii) abolished the normal brain interhemispheric asymmetry of visual evoked responses. These effects are discussed in relationship to regressive events occurring during synaptogenesis, which are known to play key roles in establishing the adult structure and functional properties of the corpus callosum.

[The coexistence in Spain of risk factors in patients with a varicose syndrome]

A prospective guided and "canvass" type study was made during a period of time two years, completed by an specific clinical instrumented examen. A total of 702 patients, men and women, with a varicose syndrome were included. The main purpose of this work was to analyze the relationship between some risk factors and clinical evidence of such syndrome.