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DOAJ Open Access 2024
Clinical and morphological substantiation of the use of glycyrizzic acid in poultry farming

Gatiyatullin Ildar, Bazekin George, Dolinin Ilgiz

The paper presents a clinical and morphological justification for the use of glycyrrhizic acid in poultry farming. It was found that the use of glycyrrhizic acid in broiler chickens enhances the histological picture of the thymus with a pronounced image and differentiation of the cortical layer. Increased mitotic activity of thymocytes and improved blood supply to the organ were determined. Revealed, Fabricius’s bag of broiler chickens, which were given glycyrrhizic acid, has a fairly high level of functional dynamics. Installed, the thickness of the cortical layer of the thymus lobule in broiler chickens in the control group was 1.2 times lower than after the use of glycyrrhizic acid in broiler chickens in the experimental group, and the cerebral layer was 1.8 times less than in the experimental group. It was revealed that glycyrrhizic acid has a beneficial effect on the body of birds.

Microbiology, Physiology
DOAJ Open Access 2024
The acute stress response to two different laboratory stress tests in physically active individuals – A pilot study

Peter Raidl, Barbara Wessner, Robert Csapo

Introduction The response to stress is driven by two interdependent systems: the hypothalamic-pituitary-adrenal (HPA) axis and the autonomic nervous system (ANS), which regulate cardiac control, endocrine levels, and immune function (Tsigos et al., 2000). Previous research suggests that regular exercisers show reduced responses to acute psychosocial stressors (Mücke et al., 2018). Nevertheless, it is currently unknown if the stress response in exercisers depends on the type of stressor and physiological marker of interest. Also, little research has directly compared male and female participants. Understanding the specificity of the response is crucial for designing future research on exercise and stress. This pilot study should clarify the feasibility of the presented design and methods to address this research gap. Methods We adopted a crossover design, exposing subjects to two laboratory-based stress tests in random, counterbalanced order. The Trier Social Stress Test (TSST; Kirschbaum et al., 1993) induces psychosocial stress, while the Maastricht Acute Stress Test (MAST; Smeets et al., 2012) incorporates additional physiological components by immersing one hand in ice water. Young, healthy, physically active subjects (n = 12; 6 females, 6 males; age = 20-3 yrs) were invited to the laboratory twice, one month apart. Females were eumenorrheic and invited within the self-reported mid-luteal phase. Participants were asked to arrive well-rested and under standardized dietary conditions. After a 15-minute resting period during which baseline measures were taken, participants underwent the stress test. Subsequently, participants sat in a quiet room for follow-up sampling of heart rate (HR), serum blood (+0 min, +5 min, +25 min), saliva, and subjective stress via a 100 mm visual analog scale (VAS100; +0 min, +5 min, +10 min, +15 min, +25 min). Free cortisol and HR were defined as primary markers for HPA and ANS activity, respectively, and analyzed using a [timepoint x test x sex] ANOVA followed by the Games-Howell. VAS100 was analyzed using continuous ordinal regression. Results HR was higher during the TSST than the MAST (∆ HR = 21.1 bpm, 95% CI [8.8, 33.4]). No sex differences for HR were found. Sex differences indicate lower cortisol in females (g = 0.87, 95% CI [0.49, 1.26]), but no time- or interaction effects were found (p > 0.05). VAS100 significantly increased following the stress tests. The MAST evoked higher VAS100 than the TSST (g = 0.46, 95% CI [0.13, 0.79]), and women reported higher levels of subjective stress than men (g = 0.62, 95% CI [0.29, 0.95]). Discussion While HR is a marker of ANS activity, the amount of movement during the interview phase might increase HR during the TSST. On the other hand, the VAS100 might reflect the physical pain experienced by the ice water and less so the psychosocial component. Despite increases in subjective stress, cortisol levels exhibited no change. This difference is in line with previous work hypothesizing even a protective effect of cortisol on subjective stress (Het et al., 2012). We conclude that the design is promising for testing hypotheses concerning the physiological and subjective stress response during acute laboratory stress tests in an exercising population. As this is a pilot study, inferential statistics should be read cautiously. This study was designed to facilitate a larger-scale project with sufficient power. References Het, S., Schoofs, D., Rohleder, N., & Wolf, O. T. (2012). Stress-induced cortisol level elevations are associated with reduced negative affect after stress: Indications for a mood-buffering cortisol effect. Psychosomatic Medicine, 74(1), 23–32. https://doi.org/10.1097/PSY.0b013e31823a4a25 Kirschbaum, C., Pirke, K. M., & Hellhammer, D. H. (1993). The ’Trier Social Stress Test’—A tool for investigating psychobiological stress responses in a laboratory setting. Neuropsychobiology, 28(1–2), 76–81. https://doi.org/10.1159/000119004 Mücke, M., Ludyga, S., Colledge, F., & Gerber, M. (2018). Influence of regular physical activity and fitness on stress reactivity as measured with the Trier Social Stress Test Protocol: A systematic review. Sports Medicine, 48(11), 2607–2622. https://doi.org/10.1007/s40279-018-0979-0 Smeets, T., Cornelisse, S., Quaedflieg, C. W. E. M., Meyer, T., Jelicic, M., & Merckelbach, H. (2012). Introducing the Maastricht Acute Stress Test (MAST): A quick and non-invasive approach to elicit robust autonomic and glucocorticoid stress responses. Psychoneuroendocrinology, 37(12), 1998–2008. https://doi.org/10.1016/j.psyneuen.2012.04.012 Tsigos, C., Kyrou, I., Kassi, E., & Chrousos, G. P. (2000). Stress: Endocrine physiology and pathophysiology. In K. R. Feingold, B. Anawalt, M. R. Blackman, A. Boyce, G. Chrousos, E. Corpas, W. W. de Herder, K. Dhatariya, K. Dungan, J. Hofland, S. Kalra, G. Kaltsas, N. Kapoor, C. Koch, P. Kopp, M. Korbonits, C. S. Kovacs, W. Kuohung, B. Laferrère, … D. P. Wilson (Eds.), Endotext. http://www.ncbi.nlm.nih.gov/books/NBK278995/

Sports, Sports medicine
DOAJ Open Access 2023
Increasing precipitation weakened the negative effects of simulated warming on soil microbial community composition in a semi-arid sandy grassland

Shaokun Wang, Shaokun Wang, Xingchi Jiang et al.

Soil microbial diversity, composition, and function are sensitive to global change factors. It has been predicted that the temperature and precipitation will increase in northern China. Although many studies have been carried out to reveal how global change factors affect soil microbial biomass and composition in terrestrial ecosystems, it is still unexplored how soil microbial diversity and composition, especially in microbial functional genes, respond to increasing precipitation and warming in a semiarid grassland of northern China. A field experiment was established to simulate warming and increasing precipitation in a temperate semiarid grassland of the Horqin region. Soil bacterial (16S) and fungal (ITS1) diversity, composition, and functional genes were analyzed after two growing seasons. The result showed that warming exerted negative effects on soil microbial diversity, composition, and predicted functional genes associated with carbon and nitrogen cycles. Increasing precipitation did not change soil microbial diversity, but it weakened the negative effects of simulated warming on soil microbial diversity. Bacterial and fungal diversities respond consistently to the global change scenario in semiarid sandy grassland, but the reasons were different for bacteria and fungi. The co-occurrence of warming and increasing precipitation will alleviate the negative effects of global change on biodiversity loss and ecosystem degradation under a predicted climate change scenario in a semiarid grassland. Our results provide evidence that soil microbial diversity, composition, and function changed under climate change conditions, and it will improve the predictive models of the ecological changes of temperate grassland in future climate change scenarios.

DOAJ Open Access 2023
Effect of white guava (Psidium guajava L.) fruit juice on the quality of lead acetate induced rats (Rattus norvegicus) spermatozoa

Annisa Alifia, Sri Mulyati, Wurlina Wurlina et al.

This study aims to determine the effect of the administration of white guava (Psidium guajava L.) fruit juice on spermatozoa plasma membrane integrity (PMI), morphological abnormality, viability, and motility of lead acetate induced rats (Rattus norvegicus). Twenty-five male rats were divided into five groups: NC (negative control) group, rats were administered with distilled water twice daily at four-hour intervals; T0 (positive control) group, rats were administered daily with lead acetate 50 mg/kg bw and distilled water four hours later; T1, T2, and T3 groups, rats were administered daily with lead acetate 50 mg/kg bw and 0.5 mL of 25, 50, and 100% white guava fruit juice four hours later. The treatment of the rats was conducted for 14 days, and on day 15, all rats were sacrificed to assess the spermatozoa quality. Data was analyzed using ANOVA followed by Duncan's multiple range test at a confidence level of 95%. The results showed that exposure to lead acetate (T0) caused lower spermatozoa PMI, viability, and motility as well as higher spermatozoa morphological abnormalities (p <0.05) compared to those of the T0 group. Administration of white guava fruit juice starting at a dose of 25% (T1) resulted in higher spermatozoa motility, viability, and PMI as well as lower spermatozoa morphological abnormalities (p <0.05) compared to rats in the T0 group. It could be concluded that white guava fruit juice maintained the spermatozoa quality of lead acetate induced rats.

Veterinary medicine, Animal biochemistry
DOAJ Open Access 2023
Morningness-eveningness Preferences among Medical Students: A Cross-sectional Study

Anju Sharma, Navneet Kumar Kaushik

Introduction: Morningness and eveningness is a phenomenon which looks at the differences among the individuals regarding their diurnal preferences, sleep-wake pattern of activity and alertness in evening or morning. Morning chronotypes are individuals who exhibit morning tendencies like rising early in the morning while evening chronotypes prefer to get up later in the morning and stay awake later at night time and also perform their best during late afternoon or evening. Morning chronotypes are known to exhibit better physical and mental health, greater self-esteem and academic performance. Aim: To estimate the prevalence of morningness and eveningness among medical students. Association of chronotype with academic performance was also determined. Materials and Methods: The present cross-sectional study was conducted on 110 apparently healthy medical students at Shaheed Hasan Khan Mewati Government Medical College, Nalhar, Haryana, India from October 2021 to January 2022. All the participants were sent a validated Morningness-Eveningness self-assessment Questionnaire (MEQ). Data of chronotypic preferences expressed as frequencies of participants (%) and association determined using Pearson’s Chi-square test and p-value <0.05 was considered statistically significant. Results: Study revealed that 67 (61%) students belonged to the Intermediate (I) chronotype, around one-fourth {26 (24%)} were Morning (M) type while 17 (15%) were Evening (E) type. Morningness was more frequently reported by females as compared to males in 8 (28%) vs. 18 (22%), respectively. Higher scores (≥50%) were more prevalent among M types as compared E types in 10 (38%) vs. 3 (18%), respectively}; however, association between chronotype and academic performance could not reach significant level (p-value=0.15). Conclusion: The distribution of chronotypes in study sample provided the evidence that majority of students could be classified as intermediate type. Morningness was more frequent in females as compared to males. Further studies with large sample size are needed to explore the influence of chronotype on academic performance.

DOAJ Open Access 2022
Pancreas Fat, an Early Marker of Metabolic Risk? A Magnetic Resonance Study of Chinese and Caucasian Women: TOFI_Asia Study

Ivana R. Sequeira, Ivana R. Sequeira, Wilson C. Yip et al.

ObjectivePrevalence of type 2 diabetes (T2D) is disproportionately higher in younger outwardly lean Asian Chinese compared to matched Caucasians. Susceptibility to T2D is hypothesised due to dysfunctional adipose tissue expansion resulting in adverse abdominal visceral and organ fat accumulation. Impact on early risk, particularly in individuals characterised by the thin-on-the-outside-fat-on-the-inside (TOFI) phenotype, is undetermined.MethodsSixty-eight women [34 Chinese, 34 Caucasian; 18–70 years; body mass index (BMI), 20–45 kg/m2] from the TOFI_Asia study underwent magnetic resonance imaging and spectroscopy to quantify visceral, pancreas, and liver fat. Total body fat was (TBF) assessed by dual-energy x-ray absorptiometry, and fasting blood biomarkers were measured. Ethnic comparisons, conducted using two-sample tests and multivariate regressions adjusted for age, % TBF and ethnicity, identified relationships between abdominal ectopic fat depots with fasting plasma glucose (FPG), insulin resistance (HOMA2-IR), and related metabolic clinical risk markers in all, and within ethnic groups.ResultsDespite being younger and of lower bodyweight, Chinese women in the cohort had similar BMI and % TBF compared to their Caucasian counterparts. Protective high-density lipoprotein cholesterol, total- and high-molecular weight adiponectin were significantly lower, while glucoregulatory glucagon-like peptide-1 and glucagon significantly higher, in Chinese. There were no ethnic differences between % pancreas fat and % liver fat. However, at low BMI, % pancreas and % liver fat were ∼1 and ∼2% higher in Chinese compared to Caucasian women. In all women, % pancreas and visceral adipose tissue had the strongest correlation with FPG, independent of age and % TBF. Percentage (%) pancreas fat and age positively contributed to variance in FPG, whereas % TBF, amylin and C-peptide contributed to IR which was 0.3 units higher in Chinese.ConclusionPancreas fat accumulation may be an early adverse event, in TOFI individuals, with peptides highlighting pancreatic dysfunction as drivers of T2D susceptibility. Follow-up is warranted to explore causality.

DOAJ Open Access 2021
Skeletal muscle fibers play a functional role in host defense during sepsis in mice

Orlando Laitano, Gerard P. Robinson, Kevin O. Murray et al.

Abstract Skeletal muscles secrete a wide variety of immunologically active cytokines, but the functional significance of this response to in vivo innate immunity is not understood. We addressed this by knocking out the toll receptor adapter protein, Myd88, only in skeletal muscle fibers (skmMyd88KO), and followed male and female mice at 6 and 12 h after peritoneal injection of cecal slurry (CS), a model of polymicrobial sepsis. Because of a previously identified increase in mortality to CS injection, males received ~ 30% lower dose. At 12 h, skmMyd88KO caused significant reductions in a wide variety of pro- and anti-inflammatory plasma cytokines, e.g. TNFα, IL-1β and IL-10, compared to strain-matched controls in both males and females. Similar reductions were observed at 6 h in females. SkmMyd88KO led to ~ 40–50% elevations in peritoneal neutrophils at 6 and 12 h post CS in females. At 12 h post CS, skmMyd88KO increased peritoneal monocytes/macrophages and decreased %eosinophils and %basophils in females. SkmMyd88KO also led to significantly higher rates of mortality in female mice but not in males. In conclusion, the results suggest that skeletal muscle Myd88-dependent signal transduction can play functionally important role in normal whole body, innate immune inflammatory responses to peritoneal sepsis.

Medicine, Science
DOAJ Open Access 2021
Contributions of Climate and Soil Properties to Wheat and Maize Yield Based on Long-Term Fertilization Experiments

Shengbao Wei, Anchun Peng, Xiaomin Huang et al.

Identifying the contributions of climate factors and soil fertility to crop yield is significant for the assessment of climate change impacts on crop production. Three 20-year field experiments were conducted in major Chinese wheat-maize cropping areas. Over the 20-year period, crop yield and soil properties showed significantly dissimilar variation trends under similar climate changes at each experimental site. The correlation between climatic factors and crop yield varied greatly among the fertilization regimes and experimental sites. Across all the fertilization regimes and the experimental sites, the average contribution rates of soil properties to wheat and maize yield were 45.7% and 53.2%, respectively, without considering climate factors, and 40.4% and 36.6%, respectively, when considering climate factors. The contributions of soil properties to wheat and maize yield variation when considering climate factors were significantly lower than those without considering climate factors. Across all experimental sites and all fertilization regimes, the mean contribution rates of climate factors to wheat and maize yield were 29.5% and 33.0%, respectively. The contribution rates of the interaction of climate and soil to wheat and maize yield were 3.7% and −0.9%, respectively. Under balanced fertilization treatments (NPK and NPKM), the change in the contribution rate of soil properties to wheat or maize yield was not obvious, and the average contribution rates of the interaction of climate and soil to wheat and maize yield were positive, at 14.8% and 9.5%, respectively. In contrast, under unbalanced fertilization treatments (CK and N), the contribution rates of soil properties to wheat or maize yield decreased, and the average contribution rates of the interaction of climate and soil were negative, at −7.4% and −11.2%, respectively. The above results indicate that climate and soil synergistically affected crop yields and that, with the optimization of the fertilization regime, positive interactions gradually emerged.

DOAJ Open Access 2021
Productivity of Spring Wheat Using Megamix Mineral Fertilizers

Vasin Vasily, Burunov Alexey, Vasina Natalia et al.

The paper shows the research results related to the development of methods to increase the yield of spring wheat using Megamix liquid mineral fertilizers in the presowing treatment of seeds, treatment of crops on vegetation when introducing mineral fertilizers in seedbed preparation in the forest-steppe conditions of the Middle Volga region. The studies were carried out on the experimental field of Samara State University in 2017-2020. During the three-factor field experiment, dry matter accumulation and photosynthetic activity were evaluated with the analysis of photosynthetic potential and net productivity of photosynthesis. It was established that the best indicators are formed on versions with the treatment of seeding material with Megamix Seeds or Megamix Profi agents with subsequent double treatment on vegetation with Megamix Profi in the amount of 0.5l/ha (in the tillering phase) + Megamix Nitrogen in the amount of 0.5l/ha (in the flag leaf phase) against the background of N32P32K32 fertilizer application. The application of Megamix agents in the system of seed treatment + treatment of crops with Megamix stimulating agents provides the maximum accumulation of dry matter in the version of Megamix Seeds treatment and the treatment of crops with a mixture of Megamix Profi + Megamix Nitrogen – 591.9 g/m on soft crops and 622.6 g/m2 – durum wheat against the background of N32P32K32 application. The maximum photosynthetic potential of 0.968…1.091 million m2/ha per day is formed in these versions, and, consequently, the maximum yields with values of 3.73 t/ha on soft wheat crops and 3.44 t/ha on durum wheat crops. It was found that the use of liquid mineral fertilizers on all versions of the experiment reliably increases the yield of spring wheat.

Microbiology, Physiology
DOAJ Open Access 2020
Natural Phenolic Acid, Product of the Honey Bee, for the Control of Oxidative Stress, Peritoneal Angiogenesis, and Tumor Growth in Mice

Nada Oršolić, Martina Kunštić, Marina Kukolj et al.

Tumor-associated macrophages (TAM) are key regulators of the link between inflammation and cancer, and the interplay between TAM and tumor cells represents a promising target of future therapeutic approaches. We investigated the effect of gallic acid (GA) and caffeic acid (CA) as strong antioxidant and anti-inflammatory agents on tumor growth, angiogenesis, macrophage polarization, and oxidative stress on the angiogenic model caused by the intraperitoneal (<i>ip</i>) inoculation of Ehrlich ascites tumor (EAT) cells (2.5 × 10<sup>6</sup>) in Swiss albino mouse. Treatment with GA or CA at a dose of 40 mg/kg and 80 mg/kg <i>ip</i> was started in exponential tumor growth phase on days 5, 7, 9, and 11. On day 13, the ascites volume and the total number and differential count of the cells present in the peritoneal cavity, the functional activity of macrophages, and the antioxidant and anti-angiogenic parameters were determined. The results show that phenolic acids inhibit the processes of angiogenesis and tumor growth, leading to the increased survival of EAT-bearing mice, through the protection of the tumoricidal efficacy of M1 macrophages and inhibition of proangiogenic factors, particularly VEGF, metalloproteinases -2 and -9, and cyclooxygenase-2 activity.

Organic chemistry
DOAJ Open Access 2020
Neuromyelitis optica: a pilot study of clinical presentation and status of serological biomarker AQP4 among patients admitted to a tertiary centre in NCNS, Sudan

Etedal Ahmed AbuElbasher Ibrahim, Fatima Gammer, Alsadig Gassoum

Abstract Background Neuromyelitis optica (NMO) is a demyelinating disease primarily affecting the optic nerves and spinal cord. It is distinguished from other demyelinating conditions by the presence of AQP4-IgG and serum aquaporin 4 (AQP4), found mainly in the blood–brain barrier. This descriptive study was conducted from January 2015 to June 2018 at the National Center for Neurological Sciences (NCNS) in Khartoum, Sudan. All participants were Sudanese patients diagnosed with NMO. In our study the selection of cases was based on Dean Wingerchuk diagnostic criteria (2006), which states that the diagnosis of NMO should meet two absolute criteria and two supportive criteria. The absolute criteria are myelitis and optic neuritis, whereas supportive criteria include radiological findings obtained from brain and spinal cord MRI. Furthermore, AQP4-IgG levels were measured from cerebrospinal fluid (CSF) and serum using immunofluorescence. Data were collected by a pre-designed questionnaire and analyzed using SPSS version 17. A p value < 0.05 was considered statistically significant. Results A total of 31 patients were enrolled in this study [6 male (19.4%) and 25 female (80.6%)]. The mean age was 38 ± 12.8 years. Motor and visual difficulties were the initial symptoms and occurred in 21 (67.7%) and 10 (32.3%) patients, respectively. Fundoscopy confirmed optic atrophy in 22 (71.0%) patients. The course of the disease revealed one relapse in 21 patients (67.7%). Seropositive AQP4-IgG were seen in 23 patients (79.31%). There was a significant correlation between AQP4 and response to treatment (p ≤ 0.038). The correlation between serum AQP4-IgG, showed that, complete improvement was detected in 2 patients (6.9%) one of them was positive and the other was negative, 20 (69.0%) patients presented with some disability, among them 18 (62.1%) were positive and 2 (6.9%) were negative, while 7 patients showed no improvement (24.1%) 4 out of them were positive (13.8%) and 3 were negative (10.3%). Conclusion At the initial presentation of NMO, longitudinal myelitis was observed more frequently than optic neuritis. More than two third of the patients showed strong seropositivity for serum AQP4. Most seropositive patients showed a good response to treatment but with residual disabilities.

Neurosciences. Biological psychiatry. Neuropsychiatry, Neurophysiology and neuropsychology

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