A single dose ChAdOx1 nCoV-19 vaccine elicits high antibody responses in individuals with prior SARS-CoV-2 infection comparable to that of double dose vaccinated SARS-CoV-2 infection naïve individuals

Background A single dose COVID-19 vaccines, mostly mRNA-based vaccines, are shown to induce robust antibody responses in individuals who were previously infected with SARS-CoV-2, suggesting the sufficiency of a single dose to those individuals. However, these important data are limited to developed nations and lacking in resource-limited countries, like Ethiopia. Methods We compared receptor-binding domain (RBD)-specific IgG antibodies in 40 SARS-CoV-2 naïve participants and 25 participants previously infected with SARS-CoV-2, who received two doses of ChAdOx1 nCoV-19 vaccine. We measured the antibody response in post-vaccination blood samples from both groups of participants collected at four different post-vaccination time points: 8- and 12-weeks after each dose of the vaccine administration using an in-house developed ELISA. Results We observed a high level of anti-RBD IgG antibodies titers 8-weeks after a single dose administration (16/27; 59.3%) among naïve participants, albeit dropped significantly (p<0.05) two months later, suggesting the protective immunity elicited by the first dose ChAdOx1 nCoV-19 vaccine will likely last for a minimum of three months. However, as expected, a significant (p<0.001) increase in the level of anti-RBD IgG antibodies titers was observed after the second dose administration in all naïve participants. By contrast, the ChAdOx1 nCoV-19 vaccine-induced anti-RBD IgG antibody titers produced by the P.I participants at 8- to 12-weeks post-single dose vaccination were found to be similar to the antibody titers seen after a two-dose vaccination course among infection- naïve participants and showed no significant (p>0.05) increment following the second dose administration. Conclusion Taken together, our findings show that a single ChAdOx1 nCoV-19 dose in previously SARS-CoV-2 infected individuals elicits similar antibody responses to that of double dose vaccinated naïve individuals. Age and sex were not associated with the level of vaccine-elicited immune responses in both individuals with and without prior SARS-CoV-2 infection. Further studies are required to assess the need for a booster dose to extend the duration and amplitude of the specific protective immune response in Ethiopia settings, especially following the Omicron pandemic.

The relationship of estrus character before double dose artificial insemination in Limousin Crossbred cow

Ongole cattle in smallholder farms on Java, Indonesia, have been crossed with Limousin, which is not controlled repeatedly. The character of estrus affects the success of Artificial Insemination. This study aimed to determine the relationship between estrus characters before double dose artificial insemination using frozen semen sexing. The research was conducted in Senggreng Village, Sumber Pucung District, Malang Regency. The material was 45 head of Limousin crossbred cow inseminated using sexing semen produced by the Singosari National Artificial Insemination Center (SNAIC). The sexed semen processed with the Percoll Density Gradient Centrifugation (PDGC) method. The average body value of cows between 3-5 (scale 1-9) with an average age of 1.8-7 years, normal reproduction, clear signs of estrus. The reproductive organs were examined by rectal palpation to confirm that the cows are not pregnant. Parameters of estrus character were vulvar color, cervical mucus, vaginal temperature, pH, vulvar swelling, and heat detector value. The result showed that the estrus characters, including vulva color, vulva swelling, cervical mucus, vaginal temperature, cervical mucus pH, and heat detector score in the first and second artificial insemination have a low relationship. The regression models produced can be used but are less precise to estimate the relationship between estrus characters because the coefficient of determination shows a low influence.

Neutralization of ancestral SARS-CoV-2 and variants Alpha, Beta, Gamma, Delta, Zeta and Omicron by mRNA vaccination and infection-derived immunity through homologous and heterologous variants

Emerging SARS-CoV-2 variants of concern/interest (VOC/VOI) raise questions about effectiveness of neutralizing antibodies derived from infection or vaccination. As the population immunity to SARS-CoV-2 has become more complex due to prior infection and/or vaccination, understanding the antigenic relationship between variants is needed. Here, we have assessed in total 104 blood specimens from convalescent individuals after infection with early-pandemic SARS-CoV-2 (pre-VOC) or with Alpha, Beta, Gamma or Delta, post-vaccination after double-dose mRNA-vaccination and break through infections due to Delta or Omicron. Neutralization against seven authentic SARS-CoV-2 isolates (B.1, Alpha, Beta, Gamma, Delta, Zeta, Omicron) was assessed by plaque-reduction neutralization assay. We found highest neutralization titers against the homologous (previously infecting) variant, with lower neutralization efficiency against heterologous variants. Significant loss of neutralization for Omicron was observed but to a varying degree depending on previously infecting variant (23.0-fold in Beta-convalescence up to 56.1-fold in Alpha-convalescence), suggesting that infection-derived immunity varies, but independent of the infecting variant is only poorly protective against Omicron. Of note, Zeta VOI showed also pronounced escape from neutralization of up to 28.2-fold in Alpha convalescent samples. Antigenic mapping reveals both Zeta and Omicron as separate antigenic clusters. Double dose vaccination showed robust neutralization for Alpha, Beta, Gamma, Delta and Zeta, with fold-change reduction of only 2.8 (for Alpha) up to 6.9 (for Beta). Escape from neutralization for Zeta was largely restored in vaccinated individuals, while Omicron still showed a loss of neutralization of 85.7-fold compared to pre-VOC SARS-CoV-2. Combined immunity from infection followed by vaccination or vaccine breakthrough infection showed highest titers and most robust neutralization for heterologous variants. Breakthrough infection with Delta showed only 12.5-fold reduced neutralization for Omicron, while breakthrough infection with Omicron showed only a 1.5-fold loss for Delta, suggests that infection with antigenically different variants can boost immunity for antigens closer to the vaccine strain. Antigenic cartography showed also a tendency towards broader neutralizing capacity for heterologous variants. We conclude that the complexity of background immunity needs to be taken into account when assessing new VOCs. Development towards separate serotypes such as Zeta was already observed before Omicron emergence, thus other factors than just immune escape must contribute to Omicrons rapid dominance. However, combined infection/vaccination immunity could ultimately lead to broad neutralizing capacity also against non-homologous variants.

Effect of different fertilizer doses on the production of Chaite-5 paddy variety in Dhanusha District, Nepal

The application of inorganic nutrient sources is necessary for proper agricultural growth that can ensure high quality food production. A field experiment was carried out in Hansapur, Dhanusha from March 2021 to July 2021 to study the effect of different fertilizer doses on the growth and yield of rice. The experiment was set up in a randomized complete block design (RCBD) with 7 different treatments following three replications. The treatments were named as T1: Control, T2: RDF (Recommended dose of fertilizers - 100:30:30 kg NPK/ha), T3: Double dose of RDF (200: 60: 60 kg NPK/ha), T4: A half dose of RDF (50: 15: 15 kg NPK/ha), T5: 125% dose of RDF (125: 37.5: 37.5 kg NPK/ha), T6: Locally available Azolla (300 kg/ha), and T7: FYM (6 ton/ha), respectively. Different doses of RDF showed a significant effect on growth, yield, and yield contributing characters of Chaite-5 variety. Results of the study showed that the application of a double dose of RDF (200: 60: 60 kg NPK/ha) gave the maximum yield (9.50 ton/ha). It was also recorded that 125% dose of RDF, recommended dose of fertilizers and FYM gave satisfactory results. Results revealed that the highest plant height, effective tillers/hill, panicle number, panicle length, total spikelet/hill, 1000-grain weight, grain yield, and straw yield were obtained from the use of a double dose of RDF (200: 60: 60 kg NPK/ha). It was observed that yield of rice can be increased substantially with the application of higher doses of nitrogenous fertilizers. Hence, a double dose of fertilizer can be the best supplement for improving growth and yield in rice.

Varying Effects of Organic Waste Products on Yields of Market Garden Crops in a 4-Year Field Experiment under Tropical Conditions

Controlling organic and mineral fertilisation is a major concern in tropical environments. An experiment was conducted on an arenosol in the Dakar region, the main market gardening area of Senegal, to evaluate treatments commonly used by farmers. Seven treatments were repeated three times: A mineral fertilisation (MF) treatment based on N-P2O5-K2O (10-10-20), and three organic treatments at two doses (dried sewage sludge (SS), poultry litter (PL) and a digestate from an anaerobic digestion (AD) of cow manures). Each of the organic treatments were supplemented with a normal dose (1) and a double dose (2) of mineral N and K fertiliser. A lettuce, carrot and tomato rotation was grown in four campaigns (2016–2020) on all of the plots. Yields of all three crops in all of the organic treatments were statistically similar (p > 0.05) to the MF in all four campaigns, except for the yield of the lettuce crop under treatment PL-2 in campaigns 2 and 3. The tomato yields were statistically similar under all of the organic treatments in all four campaigns. In contrast, the yields of the lettuce and carrot crops differed statistically from each other and under the different organic treatments in all four campaigns. The yields of all three crops differed in the campaigns with the fertilisation treatment. In each campaign, the yields of each crop were not correlated with the total amounts of N, P and K applied. These differences or similarities in yields are explained by the nature of the organic waste products, the accumulation of nutrients after several applications, the type of crop and interannual differences in temperature.

Effect of application of microelements on nitrogen nutrition of parsley, yield and quality of greens and roots

The article presents the results of vegetation-field studies (for 2018-2020) to study the effect of trace elements on the yield and quality of greens and root crops of parsley on heavy loamy chernozems on loess-like loams. A soil mixture was poured into the vessel at the rate of 10 kg of heavy loamy chernozem. Microelements were introduced into the soil in an amount: boron – 1.0 mg; zinc – 2.5 mg; copper – 0.5 mg; manganese – 5.0 mg; molybdenum – 1.0 mg; cobalt – 1.0 mg; iodine – 2.0 mg of active ingredient per kilogram of soil. In the prepared soil, 100 parsley seeds were sown in vessels at the beginning of May. Trace elements were aplicated in the form of an aqueous solution of salts 20 days before chemical analyzes. Molybdenum in the form of ammonium molybdenum (0.05 % solution), manganese – in the form of manganese sulfate (0.6 %, solution) and boron – in the form of boric acid (0.15 % solution). The experiments were carried out in triplicate. Collecting greens was carried out when the plants reached a height of 20–25 cm, leaving petioles 2 cm high from the head of the root crop. The results of the research found that microelements: boron, copper, manganese, molybdenum and cobalt on chernozem on average over two years contributed to an increase in seed germination by 1.2–1.3 %, and the introduction of iodine into the soil slightly reduced seed germination. Parsley shoots appeared together, which was also influenced by the water–air properties of the soil. At the same time, the plants were well leafy and had a darker green color of the leaves, increased the productivity of greens and parsley root crops. In the variant where organic fertilizers were applied to the soil under the predecessor, the microelements increased the yield. This is due to the fact that organic fertilizers were introduced under the previous crop, when decomposed in the soil, they provide the plants with microelements. The increased yield of parsley root crops was obtained from the introduction of molybdenum and a double dose of copper. An increased yield of root crops compared to the control (without feeding) was obtained, respectively: cobalt – 151 g, double dose of copper – 135 g, copper – 108 g and zinc – 106 g. Thus, the use of trace elements for parsley in order to obtain high yield and quality marketable products are best used on poor soils of these elements.

Immune Response to Hepatitis B Virus Vaccine Among People Living With HIV: A Meta-Analysis

BackgroundThere is conflicting evidence about whether a double dose of the hepatitis B virus (HBV) vaccine induces better immunity than the standard-dose vaccine for people living with HIV (PLWH). This study provides a meta-analysis that summarizes the efficacy of HBV vaccine regimens among HIV-infected patients, clarifying the role of particular factors such as dose and frequency of vaccination in vaccine responsiveness and highlighting the need for evidence-based practice to assess HBV vaccination among PLWH.MethodsRandomized clinical trials (RCTs) and prospective studies reporting vaccination response rates among PLWH were found through a search of PubMed, Cochrane, and the Web of Science. The key outcome was vaccine response. A random-effects model was used to estimate the pooled response rate. Subgroup analysis was conducted to evaluate key factors and explore sources of heterogeneity. Possible biases were assessed using quality and publication bias assessment.ResultsEligible studies included controlled trials that examined the effects of 17 interventional studies with 1,821 participants. Among PLWH who received the HBV vaccine, the pooled response rate of HBV vaccination was 71.5% (95% CI 64.0%–77.9%, p &lt; 0.001). Compared with the standard dose (65.5%, 95% CI 53.1%–76.1%), the double dose (75.2%, 95% CI 66.2%–82.5%) was associated with a better response rate [Q(1) = 19.617, p &lt; 0.001]. When stratified by schedule, the four-dose schedule (89.7%, 95% CI 83.1%–93.9%) had a higher response rate than the three-dose schedule (63.3%, 95% CI 56.6%–69.4%) and the difference was significant [Q(1) = 88.305, p &lt; 0.001]. PLWH with higher CD4+ T-cell counts (&gt;500 cells/mm3) at the time of vaccination had better response rates [Q(1) = 88.305, p &lt; 0.001].ConclusionsIn this meta-analysis, the double dose of the HBV vaccine and multiple injections were associated with better immune responses than the standard HBV vaccine regimen in PLWH. Higher seroconversion rates were observed in PLWH with high CD4+ T-cell levels, indicating that individuals infected with HIV should receive the HBV vaccine as soon as possible after diagnosis.Systematic Review Registrationhttps://www.crd.york.ac.uk/PROSPERO/.

HYPERGLYCEMIA REVERSAL IN DIABETIC INFARCTED RAT POSTINTRAVENOUS INFUSION OF HUMAN MESENCHYMAL STEM CELLS

INTRODUCTION Hyperglycemia reversal and preservation/restoration of β-cells function in diabetic infarction remains as an attractive and challengeable therapeutic target. Mesenchymal stem cells (MSCs) are multipotent cells with a strong immunoregulatory potential that have emerged as a possible cell-based therapy for a variety of immunological diseases. The objective of this study was to examine the dose-dependent efcacy of intravenous administration of human umbilical cord blood derived MSCs (UCB-MSCs) in chemically induced rats with diabetic infraction. METHODS Wister rats (weight: 200-250g, males) received intraperitoneal streptozotocin injection followed by isoproterenol to develop diabetes infarction condition. After model development animals received intravenous single or double dose of human 6 UCB-MSCs (5 X 10 cells per animal at each dose) and followed up to 30 days post-administration. Pancreatic tissue histology, blood glucose and insulin levels were measured, and proportion of animal survival was calculated using Kaplan-Meier curve analysis. RESULTS Double dose of MSCs infusion resulted in reorganization of islet cells and partial restoration of β-cells at day 30. Comparatively faster restoration of glucose and insulin normalization was observed for two MSCs doses compared to single dose. Highest proportion of animal survival was observed (>85%) for double doses of MSCs infusion compared to single dose (>70%) at day 30. CONCLUSION Two consecutive intravenous doses of human UCB-MSCs can improve structural and functional decits of pancreatic tissues and maintain blood glucose and insulin levels in diabetic infarcted rats up to 30 days. However, identication of long-term effects entails longer follow-up periods, and larger sample sizes with other investigations.