Response of antibody titers to SARS-CoV-2 vaccination and clinical outcomes during the predominance of the Omicron variant in Colombia

Introduction

The response to vaccination against the virus that causes severe acute respiratory infection syndrome coronavirus 2 is lower in renal transplant recipients than in the general population. The data obtained from Latin America showed reduced immunogenicity under inactivated virus vaccination schedules and messenger ribonucleic acid platforms.

Methods

A retrospective cohort study including renal transplant recipients from Colombia with a two-dose vaccination schedule against severe acute respiratory infection syndrome coronavirus 2 with Pfizer, AstraZeneca, Moderna, Jansen, and Sinovac vaccines between March 1, 2021 and December 1, 2021, was carried out with a follow-up period to evaluate outcomes until May 2022. The outcomes correspond to the titers of immunoglobulin G antibodies against the receptor binding domain of the severe acute respiratory infection syndrome coronavirus 2 spike and a composite outcome of mortality, general, and intensive care unit hospitalization.

Results

In total, 215 renal transplant recipients with two doses of vaccination for severe acute respiratory infection syndrome coronavirus 2 during the predominance of the Omicron variant in Colombia were included, with the measurement of immunoglobulin G antibody titers against the receptor binding domain of the severe acute respiratory infection syndrome coronavirus 2 spike at 8 weeks of vaccination. The mean age was 52.1 years, and the standard deviation was ± 14.2; severe acute respiratory infection syndrome coronavirus 2 infection occurred in 20% of the population, of which 23.26% required hospitalization, 13.95% were under intensive care unit management, and four cases of mortality (9.3%) were reported. Of the total population, 52.5% had antibody titers higher than 0.8 IU/mL (median 0.77 IU/mL, interquartile range 0.4-131). Patients with severe acute respiratory infection syndrome coronavirus 2 infection had a median antibody titer of 0.4 IU/mL (interquartile range 0.4-3.45), and those without infection had a median antibody titer of 1.8 IU/mL (interquartile range 0.4-202) (p = 0.015).

Conclusion

Anti-severe acute respiratory infection syndrome coronavirus 2 antibody titers with a cutoff point less than 0.8 IU/mL are associated with increased risk of severe acute respiratory infection syndrome coronavirus 2 infection.

Photoelectron Spectroscopy of Oppositely Charged Molecular Switches in the Aqueous Phase: Theory and Experiment

XUV photoelectron spectroscopy (XPS) is a powerful method for investigating the electronic structures of molecules. However, the correct interpretation of results in the condensed phase requires theoretical models that account for solvation. Here we present experimental aqueous-phase XPS of two organic biomimetic molecular switches, NAIP and p-HDIOP. These switches are structurally similar, but have opposite charges and thus present a stringent benchmark for solvation models which need to reproduce the observed ΔeBE = 1.1 eV difference in electron binding energy compared to the 8 eV difference predicted in the gas phase. We present calculations using implicit and explicit solvent models. The latter employs the average solvent electrostatic configuration and free energy gradient (ASEC-FEG) approach. Both nonequilibrium polarizable continuum models and ASEC-FEG calculations give vertical binding energies in good agreement with the experiment for three different computational protocols. Counterions, explicitly accounted for in ASEC-FEG, contribute to the stabilization of molecular states and reduction of ΔeBE upon solvation.

Large Shape Staggering in Neutron-Deficient Bi Isotopes

The changes in the mean-square charge radius (relative to ^{209}Bi), magnetic dipole, and electric quadrupole moments of ^{187,188,189,191}Bi were measured using the in-source resonance-ionization spectroscopy technique at ISOLDE (CERN). A large staggering in radii was found in ^{187,188,189}Bi^{g}, manifested by a sharp radius increase for the ground state of ^{188}Bi relative to the neighboring ^{187,189}Bi^{g}. A large isomer shift was also observed for ^{188}Bi^{m}. Both effects happen at the same neutron number, N=105, where the shape staggering and a similar isomer shift were observed in the mercury isotopes. Experimental results are reproduced by mean-field calculations where the ground or isomeric states were identified by the blocked quasiparticle configuration compatible with the observed spin, parity, and magnetic moment.

Towards high-resolution laser ionization spectroscopy of the heaviest elements in supersonic gas jet expansion

Resonant laser ionization and spectroscopy are widely used techniques at radioactive ion beam facilities to produce pure beams of exotic nuclei and measure the shape, size, spin and electromagnetic multipole moments of these nuclei. However, in such measurements it is difficult to combine a high efficiency with a high spectral resolution. Here we demonstrate the on-line application of atomic laser ionization spectroscopy in a supersonic gas jet, a technique suited for high-precision studies of the ground- and isomeric-state properties of nuclei located at the extremes of stability. The technique is characterized in a measurement on actinium isotopes around the N=126 neutron shell closure. A significant improvement in the spectral resolution by more than one order of magnitude is achieved in these experiments without loss in efficiency.

Estimation of the Maximal Lactate Steady State in Endurance Runners

This study aimed to predict the velocity corresponding to the maximal lactate steady state (MLSSV) from non-invasive variables obtained during a maximal multistage running field test (modified University of Montreal Track Test, UMTT), and to determine whether a single constant velocity test (CVT), performed several days after the UMTT, could estimate the MLSSV. Within 4-5 weeks, 20 male runners performed: 1) a modified UMTT, and 2) several 30 min CVTs to determine MLSSV to a precision of 0.25 km·h(-1). Maximal aerobic velocity (MAV) was the best predictor of MLSSV. A regression equation was obtained: MLSSV=1.425+(0.756·MAV); R(2)=0.63. Running velocity during the CVT (VCVT) and blood lactate at 6 (La6) and 30 (La30) min further improved the MLSSV prediction: MLSSV=VCVT+0.503 - (0.266·ΔLa30-6); R(2)=0.66. MLSSV can be estimated from MAV during a single maximal multistage running field test among a homogeneous group of trained runners. This estimation can be further improved by performing an additional CVT. In terms of accuracy, simplicity and cost-effectiveness, the reported regression equations can be used for the assessment and training prescription of endurance runners.

Sprint, agility, strength and endurance capacity in wheelchair basketball players

The aims of the present study were, firstly, to determine the reliability and reproducibility of an agility T-test and Yo-Yo 10 m recovery test; and secondly, to analyse the physical characteristics measured by sprint, agility, strength and endurance field tests in wheelchair basketball (WB) players. 16 WB players (33.06 ± 7.36 years, 71.89 ± 21.71 kg and sitting body height 86.07 ± 6.82 cm) belonging to the national WB league participated in this study. Wheelchair sprint (5 and 20 m without ball, and 5 and 20 m with ball) agility (T-test and pick-up test) strength (handgrip and maximal pass) and endurance (Yo-Yo 10 m recovery test) were performed. T-test and Yo-Yo 10 m recovery test showed good reproducibility values (intraclass correlation coefficient, ICC = 0.74-0.94). The WB players' results in 5 and 20 m sprints without a ball were 1.87 ± 0.21 s and 5.70 ± 0.43 s and with a ball 2.10 ± 0.30 s and 6.59 ± 0.61 s, being better than those reported in the literature. Regarding the pick-up test results (16.05 ± 0.52 s) and maximal pass (8.39 ± 1.77 m), players showed worse values than those obtained in elite players. The main contribution of the present study is the characterization of the physical performance profile of WB players using a field test battery. Furthermore, we demonstrated that the agility T-test and the aerobic Yo-Yo 10 m recovery test are reliable; consequently they may be appropriate instruments for measuring physical fitness in WB.

OBLA is a better predictor of performance than Dmax in long and middle-distance well-trained runners

AIM

The main purpose of this study was to investigate if the lactate threshold estimated by the maximal deviation method (LTDmax) and the onset of blood lactate accumulation speed (LTOBLA) are good correlates of middle- and long-distance running performance in well-trained endurance runners.

METHODS

Eleven long- and eleven middle-distance runners participated in this study. All participants completed a maximal incremental running test on a treadmill to determine maximal physiological variables and velocities corresponding to LTDmax and LTOBLA (4 mmol·L-1 of lactate concentration). The relationships between LTDmax, LTOBLA and the best 10-km (S10km) and 3-km (S3km) race pace were analyzed in the long- and middle distance runners, respectively.

RESULTS

The velocities for LTDmax and LTOBLA were 17.0±0.7 km·h-1 and 17.5±1.3 km·h-1 for the long-distance runners and 16.9±1.1 km·h-1 and 17.4±1.3 km·h-1 for the middle-distance runners. A positive linear relationship was found between LTDmax and S10km (r=0.873, P<0.001), as well as between LTOBLA and S10km (r=0.919, P<0.001) in the long-distance runners. Similarly, LTDmax and LTOBLA were significantly correlated with S3km in the middle-distance runners (r=0.825, P<0.01 and r=0.849, P<0.001, respectively).

CONCLUSION

These results indicate that both LTOBLA and LTDmax are highly associated to running performance according to S10km and S3km in well-trained long- and middle-distance runners. Thus, we conclude that competitive middle- and long-distance athletes may find these measures useful to monitor running performance within 3 weeks of laboratory testing.

Interaction effects of stride angle and strike pattern on running economy

This study aimed to investigate the relationship between stride angle and running economy (RE) in athletes with different foot strike patterns. 30 male runners completed 4 min running stages on a treadmill at different velocities. During the test, biomechanical variables such as stride angle, swing time, contact time, stride length and frequency were recorded using an optical measurement system. Their foot strike pattern was determined, and VO2 at velocities below the lactate threshold were measured to calculate RE. Midfoot/forefoot strikers had better RE than rearfoot strikers (201.5±5.6 ml · kg(-1) · km(-1) vs. 213.5±4.2 ml · kg(-1) · km(-1)respectively; p=0.019). Additionally, midfoot/fore-foot strikers presented higher stride angles than rearfoot strikers (p=0.043). Linear modelling analysis showed that stride angle is closely related to RE (r=0.62, p<0.001) and that the effect of stride angle on RE was different in the 2 groups. From an arbitrary value of 4°, a rearfoot strike pattern is likely to be more economical, whereas at any lower degree, the midfoot/forefoot strike pattern appears to be more desirable. A biomechanical running technique characterised by high stride angles and a midfoot/forefoot strike pattern is advantageous for a better RE. Athletes may find stride angle useful for improving RE.

Differences in ground contact time explain the less efficient running economy in north african runners

The purpose of this study was to investigate the relationship between biomechanical variables and running economy in North African and European runners. Eight North African and 13 European male runners of the same athletic level ran 4-minute stages on a treadmill at varying set velocities. During the test, biomechanical variables such as ground contact time, swing time, stride length, stride frequency, stride angle and the different sub-phases of ground contact were recorded using an optical measurement system. Additionally, oxygen uptake was measured to calculate running economy. The European runners were more economical than the North African runners at 19.5 km · h(-1), presented lower ground contact time at 18 km · h(-1) and 19.5 km · h(-1) and experienced later propulsion sub-phase at 10.5 km · h(-1),12 km · h(-1), 15 km · h(-1), 16.5 km · h(-1) and 19.5 km · h(-1) than the European runners (P < 0.05). Running economy at 19.5 km · h(-1) was negatively correlated with swing time (r = -0.53) and stride angle (r = -0.52), whereas it was positively correlated with ground contact time (r = 0.53). Within the constraints of extrapolating these findings, the less efficient running economy in North African runners may imply that their outstanding performance at international athletic events appears not to be linked to running efficiency. Further, the differences in metabolic demand seem to be associated with differing biomechanical characteristics during ground contact, including longer contact times.

Macroalgal-associated dinoflagellates belonging to the genus Symbiodinium in Caribbean reefs

Coral-algal symbiosis has been a subject of great attention during the last two decades in response to global coral reef decline. However, the occurrence and dispersion of free-living dinoflagellates belonging to the genus Symbiodinium are less documented. Here ecological and molecular evidence is presented demonstrating the existence of demersal free-living Symbiodinium populations in Caribbean reefs and the possible role of the stoplight parrotfish (Sparisoma viride) as Symbiodinium spp. dispersers. Communities of free-living Symbiodinium were found within macroalgal beds consisting of Halimeda spp., Lobophora variegata, Amphiroa spp., Caulerpa spp. and Dictyota spp. Viable Symbiodinium spp. cells were isolated and cultured from macroalgal beds and S. viride feces. Further identification of Symbiodinium spp. type was determined by length variation in the Internal Transcribed Spacer 2 (ITS2, nuclear rDNA) and length variation in domain V of the chloroplast large subunit ribosomal DNA (cp23S-rDNA). Determination of free-living Symbiodinium and mechanisms of dispersal is important in understanding the life cycle of Symbiodinium spp.

Differences in Physical Fitness and Throwing Velocity Among Elite and Amateur Female Handball Players

This study compared physical characteristics (body height [BH], body mass [BM], body fat [BF], and fat free mass [FFM]), one repetition maximum bench press (1RM (BP)), jumping explosive power (VJ), handball throwing velocity, power-load relationship of the leg and arm extensor muscles, 5- and 15-m sprint running time, and running endurance in elite (n = 16; EF) and amateur (n = 15; AF) female handball players aged 17 - 38. Results revealed that, compared to AF, EF players presented similar values in body mass and percent body fat, but higher values (p < 0.001 - 0.05) in BH (6 %), FFM (10 %), 1RM (BP) (23 %), VJ (10 %), handball throwing velocity (11 %), power-load relationship of the arm (25 %) and leg (12 %) extensors, as well as 5- and 15-m sprint (3 - 4 %) and endurance running velocities (13 %). Univariate regression analyses showed that 1RM (BP) was associated with throwing velocity (R (2) = 0.64). The higher absolute values of maximal strength and muscle power, although explained by the differences in fat free mass, will give EF an advantage to sustain certain handball game actions. The association between 1RM (BP) and throwing velocity suggests that throwing velocity values in female handball players depend more on maximal strength than on the capacity to move low loads at high velocities, during elbow extension actions.

Oral antibiotics versus parenteral antibiotics for severe pneumonia in children

BACKGROUND

Acute respiratory infection (ARI) is one of the leading causes of morbidity and mortality in children under five years of age in developing countries. When hospitalisation is required, the usual practice includes administering parenteral antibiotics if a bacterial infection is suspected. This has disadvantages as it causes pain and discomfort to the children, which may lead to treatment refusal or reduced compliance. It is also associated with needle-related complications. In some settings this equipment is in short supply or unavailable necessitating transfer of the child, which increases risks and healthcare costs.

OBJECTIVES

To determine the equivalence in effectiveness and safety of oral antibiotic compared to parenteral antibiotic therapies in the treatment of severe pneumonia in children between three months and five years of age.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 2, 2005); MEDLINE (January 1966 to July 2005); EMBASE (January 1990 to July 2005) and LILACS (February 2005).

SELECTION CRITERIA

The review included published or unpublished randomised controlled trials (RCTs) and quasi-RCTs comparing any oral antibiotic therapy with any parenteral antibiotic therapy for the treatment of severe pneumonia in children from three months to five years of age.

DATA COLLECTION AND ANALYSIS

The search yielded more than 1300 titles. Only three studies met all criteria for eligibility. One of the identified trials is yet to publish its results. We did not perform a meta-analysis because of clinical heterogeneity of therapies compared in the included trials.

MAIN RESULTS

Campbell 1988 compared oral co-trimoxazole versus intramuscular procaine penicillin followed by oral ampicillin in 134 children. At the seventh day of follow up, treatment failure occurred in 6/66 (9.1%) in the oral co-trimoxazole group and 7/68 (10.2%) in the combined-treatment group. The risk difference was -0.01% (95% confidence interval (CI) -0.11 to 0.09). The APPIS Group 2004 evaluated 1702 patients comparing oral amoxicillin versus intravenous penicillin for two days followed by oral amoxicillin. After 48 hours, treatment failure occurred in 161/845 (19%) in the amoxicillin group and 167/857 (19%) in the parenteral penicillin group. The risk difference was -0.4% (95% CI -4.2 to 3.3). The authors reported similar recovery in both groups at 5 and 14 days.

AUTHORS' CONCLUSIONS

Oral therapy appears to be an effective and safe alternative to parenteral antibiotics in hospitalised children with severe pneumonia who do not have any serious signs or symptoms.

Differences in Physical Fitness and Throwing Velocity Among Elite and Amateur Male Handball Players

This study compared physical characteristics (body height, body mass [BM], body fat [BF], and free fatty mass [FFM]), one repetition maximum bench-press (1RM (BP)), jumping explosive strength (VJ), handball throwing velocity, power-load relationship of the leg and arm extensor muscles, 5- and 15-m sprint running time, and running endurance in two handball male teams: elite team, one of the world's leading teams (EM, n = 15) and amateur team, playing in the Spanish National Second Division (AM, n = 15). EM had similar values in body height, BF, VJ, 5- and 15-m sprint running time and running endurance than AM. However, the EM group gave higher values in BM (95.2 +/- 13 kg vs. 82.4 +/- 10 kg, p < 0.05), FFM (81.7 +/- 9 kg vs. 72.4 +/- 7 kg, p < 0.05), 1RM (BP) (107 +/- 12 kg vs. 83 +/- 10 kg, p < 0.001), muscle power during bench-press (18 - 21 %, p < 0.05) and half squat (13 - 17 %), and throwing velocities at standing (23.8 +/- 1.9 m . s (-1) vs. 21.8 +/- 1.6 m . s (-1), p < 0.05) and 3-step running (25.3 +/- 2.2 m . s (-1) vs. 22.9 +/- 1.4 m . s (-1), p < 0.05) actions than the AM group. Significant correlations (r = 0.67 - 0.71, p < 0.05 - 0.01) were observed in EM and AM between individual values of velocity at 30 % of 1RM (BP) and individual values of ball velocity during a standing throw. Significant correlations were observed in EM, but not in AM, between the individual values of velocity during 3-step running throw and the individual values of velocity at 30 % of 1RM (BP) (r = 0.72, p < 0.05), as well as the individual values of power at 100 % of body mass during half-squat actions (r = 0.62, p < 0.05). The present results suggest that more muscular and powerful players are at an advantage in handball. The differences observed in free fatty mass could partly explain the differences observed between groups in absolute maximal strength and muscle power. In EM, higher efficiency in handball throwing velocity may be associated with both upper and lower extremity power output capabilities, whereas in AM this relationship may be different. Endurance capacity does not seem to represent a limitation for elite performance in handball.

Prevalence of bancroftian filariasis in the city of Puerto Limón and the province of Limón, Costa Rica

Examination of blood from randomly selected residents in four subdivisions of Puerto Limón, Costa Rica, demonstrated Wuchereria bancrofti infection in 1.8% of 2,879 persons. Previous studies in four other subdivisions of the city revealed infection in 2.7% of 2,338 persons. In both studies the microfilaremia rate in males was approximately twice that in females. Distribution by race was similar in the two surveys, with microfilaremia in 1% of 1,052 white and 4.1% of 1,286 black residents in the first survey and 0.8% of 2,216 white and 5.4% of 663 black residents in the second. The highest rate of infection was in the 10-to 19-year-old and over 40-year-old age groups. In 13 rural communities near Puerto Limón, infection was found in only three (0.1%) of 3,448 individuals (27% of the population). Dissection revealed filarial larvae in 164 (6%) of 2,714 female Culex pipiens fatigans captured in 137 of 140 urban houses and in none of 936 from rural houses. Precipitin tests on stomach contents of 643 C. p. fatigans showed that 85% had taken human blood. The results indicate that endemic bancroftian filariasis in the Puerto Limón area is restricted to the urban population.

Bancroftian filariasis in Puerto Limón, Costa Rica

In four neighborhoods of Puerto Limón, a Caribbean coastal city in a tropical rainforest area of Costa Rica, examination of 1-ml samples of night blood from 1,142 randomly selected, and 1,196 associated, persons by the Knott and filter-chamber techniques revealed microfilariae of Wuchereria bancrofti in about 3% of the 2,338 samples. The frequency of infection was higher in males (3.9%) than in females (1.9%), higher in persons of black (4.1%) than of white (1.0%) race, and highest in persons aged 10-19 (4.0%) and over 50 years (4.8%), lowest in those under 10 years (1.1%). The median microfilaria density was 3.5, the highest 45, per 20 lambdas of blood. Microfilaremia was distinctly periodic. Dissection of 663 female Culex pipiens fatigans from 42 houses of infected persons revealed filarial larvae in 25; only 1 larva was third (infective) stage. Of 64 infected persons, 11 had clinical findings suggestive of filariasis. Elephantiasis was seen in 21 others. Other forms of symptomatic filariasis without microfilaremia, though presumed to be present, were not assessed specifically.