Hepatitis C virus infection and Parkinson's disease: insights from a joint sex-stratified BioOptimatics meta-analysis.

Hepatitis C virus (HCV) infection poses a significant public health challenge and often leads to long-term health complications and even death. Parkinson's disease (PD) is a progressive neurodegenerative disorder with a proposed viral etiology. HCV infection and PD have been previously suggested to be related. This work aimed to identify potential biomarkers and pathways that may play a role in the joint development of PD and HCV infection. Using BioOptimatics-bioinformatics driven by mathematical global optimization-, 22 publicly available microarray and RNAseq datasets for both diseases were analyzed, focusing on sex-specific differences. Our results revealed that 19 genes, including MT1H, MYOM2, and RPL18, exhibited significant changes in expression in both diseases. Pathway and network analyses stratified by sex indicated that these gene expression changes were enriched in processes related to immune response regulation in females and immune cell activation in males. These findings suggest a potential link between HCV infection and PD, highlighting the importance of further investigation into the underlying mechanisms and potential therapeutic targets involved.

Molecular aspects of copper homeostasis in fungi.

Copper homeostasis in fungi is a tightly regulated process crucial for cellular functions. Fungi acquire copper from their environment, with transporters facilitating its uptake into the cell. Once inside, copper is utilized in various metabolic pathways, including respiration and antioxidant defense. However, excessive copper can be toxic by promoting cell damage mainly due to oxidative stress and metal displacements. Fungi employ intricate regulatory mechanisms to maintain optimal copper levels. These involve transcription factors that control the expression of genes involved in copper transport, storage, and detoxification. Additionally, chaperone proteins assist in copper trafficking within the cell, ensuring its delivery to specific targets. Furthermore, efflux pumps help remove excess copper from the cell. Altogether, these mechanisms enable fungi to balance copper levels, ensuring proper cellular function while preventing toxicity. Understanding copper homeostasis in fungi is not only essential for fungal biology but also holds implications for various applications, including biotechnology and antifungal drug development.

Photobiomodulation Modulates Proliferation and Gene Expression Related to Calcium Signaling in Human Osteoblast Cells.

Introduction: Photobiomodulation with low-level laser treatment can enhance bone formation by stimulating the cell division of osteoblasts and increasing the amount of protein deposition, thus encouraging the formation of new bone. The aim of this study was to evaluate the effects of photobiomodulation with a low-level laser on proliferation and gene expression related to calcium signaling in human osteoblasts. Methods: Osteoblastic cell lines of the hFOB1.19 lineage, human osteoblasts, were grown and assigned into two groups, control (C; n=78 cultured wells) and photobiomodulation (L; n=78 cultured wells) with n=6 per day of the experimental period. Cells were cultured (immature at 34 ºC), and after maturation at 37 ºC, group L cells were exposed to laser irradiation with a low-level laser device (gallium and aluminum arsenide), at a wavelength of 808 nm, a power output of 200 mW, and a power density of 200 mW/cm2. The energy delivered to the cells was 37 J/cm2, with a beam area of 0.02 mm2 and an exposure time of 5 seconds. This treatment was applied daily for a period of 13 days. Following this, the number of cells was counted, and RNA was isolated, measured, and then converted into cDNA for further quantification using a comparative Ct method with real-time polymerase chain reaction. The results were then subjected to statistical analysis through a Mann-Whitney test, with a significance level of P<0.05. Results: The cell count in the L group (37.25x10±4±22.02) was statistically higher compared to the control group (22.75x10±4±7.660) with a P value of 0.0259. The values of 2-ΔΔCt for S100A6, plasma membrane calcium ATPase (PMCA), and calmodulin genes indicated hyper-expression on the thirteenth day, while the osteocalcin gene showed hypo-expression. Conclusion: The study suggests that the photobiomodulation mechanism with a low-level laser may regulate gene expression in human osteoblasts in a dose-dependent and cumulative manner.

Codon Optimization is Required to Express Fluorogenic Reporter Proteins in Lactococcus lactis.

Lactococcus lactis is a Gram-positive bacterium used to produce fermented foods and heterologous proteins. Its Nisin-controlled gene expression system stands out for its versatility and safety. However, the lower GC content in its genome may lead to some limitations in protein production. In this study, we explored the importance and effect of codon optimization on fluorescent reporter protein expression in L. lactis. Three non-optimized fluorescent reporter genes (gfp, rfp, and mcherry) were compared to the codon-optimized variant (mcherry-O). Parameters such as Codon Adaptation Index (CAI), Effective Number of Codons (Enc) and Guanine-Cytosine percentage (% GC) were determined to assess their influence on gene expression and protein synthesis. The production of non-optimized fluorescent proteins does not correlate with their gene expression levels, except for the codon-optimized mCherry-O protein, which was detected in the SDS-PAGE gel and the extracted lysate (visually detected). Expression of the mcherry gene was similar to the mcherry-O gene, but protein was only detected with the optimized gene. The gfp gene showed the highest expression levels, but the quantity of protein was undetectable by SDS-PAGE. The rfp gene was revealed to be an optimized gene but not tailored for L. lactis. These findings underscore the necessity of comprehensive codon optimization for foreign genes in L. lactis and reveal intriguing complexities between expression levels, RNA stability and protein synthesis.

Selecting reference genes for RT-qPCR studies involving the presence of B chromosomes in Psalidodon (Characiformes, Characidae).

BACKGROUND: B chromosomes are extra non-essential elements present in several eukaryotes. Unlike A chromosomes which are essential and present in all individuals of a species, B chromosomes are not necessary for normal functioning of an organism. Formerly regarded as genetically inactive, B chromosomes have been discovered to not only express their own genes, but also to exert influence on gene expression in A chromosomes. Recent studies have shown that, in some Psalidodon (Characiformes, Characidae) species, B chromosomes might be associated with phenotypic effects, such as changes in the reproductive cycle and gene expression. METHODS AND RESULTS: In this study, we aimed to establish stable reference genes for RT-qPCR experiments conducted on gonads of three fish species within Psalidodon genus, both in the presence and absence of B chromosomes. The stability of five selected reference genes was assessed using NormFinder, geNorm, BestKeeper, and RefFinder algorithms. We determined ppiaa and pgk1 as the most stable genes in P. fasciatus, whereas ppiaa and hmbsa showed the highest stability in P. bockmanni. For P. paranae, tbp and hprt1 were the most stable genes in females, and ppiaa and hprt1 were the most stable in males. CONCLUSIONS: We determined the most stable reference genes in gonads of three Psalidodon species considering the presence of B chromosomes. This is the first report of reference gene stability in the genus and provides valuable tools to better understand the effects of B chromosomes at gene expression level.

In Utero and Lactational Exposure to an Environmentally Relevant Mixture of Phthalates Alters Hypothalamic Gene Expression and Sexual Preference in Rats.

Several phthalates, mainly used as plasticizers, are known for their adverse effects on the male genital system. Previously, we demonstrated that an environmentally relevant mixture of six antiandrogenic phthalates (PMix), derived from a biomonitoring study in pregnant Brazilian women, was able to disrupt the reproductive development in male rats. Experimental groups (control, 0.1, 0.5, and 500 mg PMix/kg/day) were established starting from the extrapolated human dose (0.1 mg/kg/day), followed by doses 5 times and 5000 times higher. Pregnant rats received daily oral gavage administration of either vehicle (control) or PMix from gestational day 13 to postnatal day 10. Here, we examined male and female offspring regarding changes in gene expression of key reproductive factors in the hypothalamus and pituitary gland at adulthood and conducted a battery of behavioral tests in males, including partner preference, sexual behavior, and male attractiveness tests. PMix induced some changes in mating-related behavior in males, as demonstrated by the absence of preference for females against males and a higher number of penetrations up to ejaculation in the 0.5 dose group. PMix decreased Esr2 expression in the male hypothalamus across all three doses, and in females at mid and high doses in both the hypothalamus and pituitary. In male hypothalamus, we also observed decreased Kiss1 transcripts in these groups and a reduction in AR at the 0.5 dose group. In summary, our results provide further evidence that phthalates in a mixture, even at low doses, may exert cumulative effects on the structures underlying sexual behavior, which seems to be more sensitive than reproductive endpoints for the same experimental design.

Characterisation of cells markers associated with IKZF1plus in BCP-ALL.

The presence of IKZF1 deletions has been associated with an increased relapse rate in B-cell precursor acute lymphoblastic leukaemia (BCP-ALL). There is a particular subset of IKZF1del cases called IKZF1plus (defined by the co-occurrence of IKZF1del and deletions in CDKN2A/B, PAX5, or the PAR1 region, in the absence of ERG deletions), which is also associated with worse prognosis, but some recent studies have not found major differences between the IKZF1del and IKZF1plus groups. Therefore, the IKZF1plus group still needs further comprehension and our study aims to characterise the molecular heterogeneity and identify molecular markers exclusively associated with IKZF1plus. Two independent series of cases (TARGET, n = 125 and GenLAb, n = 60) were evaluated by segregating patients into 3 groups: IKZF1plus, IKZF1del, and IKZF1wild. Differential expression analyses showed that the membrane protein-coding genes most associated with the IKZF1plus group were: KCNA5, GREB1, EPOR, SDK1, and PTPRB. Notably, KCNA5 and GREB1 differential expression levels were validated in the GenLAb validation series. Regarding copy number alterations, we observed a high frequency of VPREB1 deletions in the IKZF1plus group, as well as additional exclusive deletions in the CD200 and BTLA genes. Recent research suggests that the importance of the IKZF1plus profile varies depending on the genetic subgroup. In this scenario, we found associations between IKZF1plus and certain genes in BCP-ALL, being KCNA5 and GREB1 the most promising biomarkers for predicting IKZF1plus. A deeper understanding of these genetic profiles will allow a better risk assessment and offer precise rationale for therapeutic strategies in BCP-ALL.

Virulence-Related Genes Expression in Planktonic Mixed Cultures of Candida albicans and Non-Albicans Candida Species.

INTRODUCTION: Candida albicans is the most common opportunistic pathogen causing fungal infections worldwide, especially in high-risk patients. Its pathogenicity is related to virulence factors gene expression, such as hyphal growth (HWP1), cell adhesion (ALS3), and protease secretion (SAP1) during infection spreading mechanisms. In recent years, an increase in non-albicans Candida infections has been reported, which may present coinfection or competitive interactions with C. albicans, potentially aggravating the patient's condition. This study aims to evaluate the expression of genes related to virulence factors of C. albicans and non-albicans Candida during planktonic stage. METHODS: C. albicans (ATCC MYA-3573) as well as with three clinical strains (C. albicans DCA53, C. tropicalis DCT6, and C. parapsilosis DCP1) isolated from blood samples, were grown in 24-well plates at 37°C for 20 h, either in monocultures or mixed cultures. Quantitative real-time polymerase chain reaction was used to evaluate the expression levels of the genes HWP1, ALS3, and SAP1 in cells collected during the planktonic stage. In addition, hyphal filamentation was observed using a Scanning Electron Microscope. RESULTS: The overexpression of HWP1 and ASL3 genes in mixed growth conditions between C. albicans and non-albicans Candida species suggests a synergistic relationship as well as an increased capacity for hyphal growth and adhesion. In contrast, C. parapsilosis versus C. tropicalis interaction shows an antagonistic relationship during mixed culture, suggesting a decreased virulence profile of C. parapsilosis during initial coinfection with C. tropicalis. CONCLUSION: The expression of HWP1, ALS3, and SAP1 genes associated with virulence factors varies under competitive conditions among species of the genus Candida during planktonic stage.

Effects of a Bacillus-based direct-fed microbial on performance, blood parameters, fecal characteristics, rumen morphometrics, and intestinal gene expression in finishing beef bulls.

We evaluated the effects of supplementing direct-fed microbials (DFM), containing Bacillus licheniformis and Bacillus subtilis, on performance, rumen morphometrics, intestinal gene expression, and blood and fecal parameters in finishing bulls. Nellore × Angus bulls (n = 144; initial BW = 401 ±â€…45.5 kg) were distributed at random in 36 pens (4 bulls/pen and 18 pens/treatment), following a completely randomized design. A ground corn-based finishing diet was offered for ad libitum intake twice a day for 84 d, containing the following treatments: 1) control (without DFM); 2) DFM (B. licheniformis and B. subtilis) at 6.4 × 109 CFU (2 g) per animal. The data were analyzed using the MIXED procedure of SAS, with a pen representing an experimental unit, the fixed effect of the treatment, and the random effect of pen nested within the treatment. For fecal parameters (two collections made), the collection effect and its interaction with the treatment were included in the model. Bulls that received the DFM had a decreased dry matter intake (P ≤ 0.01), did not differ in average daily gain (2.05 kg; P = 0.39), and had a 6% improvement in gain:feed (P = 0.05). The other performance variables, final BW, hot carcass weight, and hot carcass yield, did not differ (P > 0.10). Plasma urea-N concentration decreased by 6.2% (P = 0.02) in the bulls that received DFM. Glucose, haptoglobin, and lipopolysaccharides were not different between treatments (P > 0.10). Ruminal morphometrics were not affected by the treatment (P > 0.10). The use of DFM tended to reduce fecal starch (P = 0.10). At slaughter, bulls fed DFM had an increased duodenal gene expression of tryptophan hydroxylase-1 (P = 0.02) and of superoxide dismutase-1 (P = 0.03). Overall, supplementation with DFM based on B. licheniformis and B. subtilis to Nellore × Angus bulls in the finishing phase decreased dry matter intake, did not influence ADG, improved gain:feed, and increased the expression of genes important for duodenal function.

One of the main alternatives of additives to modulate the microbial population in the gastrointestinal tract (GIT), especially in the intestine, is the use of direct-fed microbials (DFM). This class of additives comprises all the feed products that contain a live or naturally occurring source of microorganism. The inclusion of DFM in diets of ruminants in the finishing phase may improve gain:feed by modifying the composition of the microbial community in the GIT to bring about a better symbiotic relationship with the host. These effects may be achieved with the use of Bacillus spp. bacteria, such as Bacillus licheniformis and Bacillus subtilis. Mixtures of these bacteria are able to foster positive effects in the finishing phase of beef cattle fed high-energy diets, which reinforces the need for studies that examine the effects and mechanisms of these species. In this study, feedlot Nellore × Angus bulls that received a DFM composed of B. licheniformis and B. subtilis had decreased dry matter intake, no influence on average daily gain, improved gain:feed, and an increase in expression of genes important for duodenal function.

TYRO3 and EPHA2 Expression Are Dysregulated in Breast Cancer.

Receptor tyrosine kinases (RTKs) are involved in cell growth, motility, and differentiation. Deregulation of RTKs signaling is associated with tumor development and therapy resistance. Potential RTKs like TAM (TYRO3, AXL, MERTK), RON, EPH, and MET have been evaluated in many cancers like lung, prostate, and colorectal, but little is known in breast tumors. In this study, 51 luminal breast cancer tissue and 8 triple negative breast cancer (TNBC) subtypes were evaluated by qPCR for the expression of TAM, RON, EPHA2, and MET genes. Statistical analysis was performed to determine the correlation to clinical data. TYRO3 is related to tumor subtype and stage, patient's age, smoking habits, and obesity. MET expression is correlated to EPHA2 and TAM gene expression. EPHA2 expression is also related to aging and smoking habits. The expression levels of the TAM and EPHA2 genes seem to play an important role in breast cancer, being also influenced by the patient's lifestyle.

Tannic acid: A possible therapeutic agent for hypermethioninemia-induced neurochemical changes in young rats.

This study explores the therapeutic benefits of tannic acid (TnA) in an experimental protocol of chronic hypermethioninemia in rats. Rats were categorized into four groups: Group I - control, Group II - TnA 30 mg/kg, Group III - methionine (Met) 0.2-0.4 g/kg + methionine sulfoxide (MS) 0.05-0.1 g/kg, Group IV - TnA/Met + MS. Saline was administered by subcutaneous pathway into groups I and II twice daily from postnatal day 6 (P6) to P28, whereas those in groups III and IV received Met + MS. From P28 to P35, groups II and IV received TnA orally. Animals from group III presented cognitive and memory impairment assessed through object recognition and Y-maze tests (p < 0.05). Elevated levels of reactive species, lipid peroxidation, and nitrites followed by a decline in sulfhydryl content, catalase activity, and superoxide dismutase activity were observed in animals treated with Met + MS (p < 0.05). However, TnA treatment reversed all these effects (p < 0.05). In group III, there was an increase in acetylcholinesterase activity and IL-6 levels, coupled with a reduction in Na+/K+-ATPase activity (p < 0.05). TnA was able to protect against these effects (p < 0.05). The gene expression of catalase, brain-derived neurotrophic factor, and nuclear factor erythroid 2-related factor 2 was decreased in the hippocampus and striatum from group III (p < 0.05). TnA reversed almost all of these alterations (p < 0.05). These findings suggest that TnA is a therapeutic target for patients with hypermethioninemia.

Changes in the molecular nodes of the Notch and NRF2 pathways in cervical cancer tissues from the precursor stages to invasive carcinoma.

Cancer is a multifactorial disease characterized by the loss of control in the expression of genes known as cancer driver genes. Cancer driver genes trigger uncontrolled cell replication, which leads to the development of malignant tumors. A cluster of signal transduction pathways that contain cancer driver genes involved in cellular processes, such as cell proliferation, differentiation, apoptosis and dysregulated organ growth, are associated with cancer initiation and progression. In the present study, three signal transduction pathways involved in cervical cancer (CC) development were analyzed: The Hippo pathway (FAT atypical cadherin, yes-associated protein 1, SMAD4 and TEA domain family member 2), the Notch pathway [cellular-MYC, cAMP response element-binding binding protein (CREBBP), E1A-associated cellular p300 transcriptional co-activator protein and F-Box and WD repeat domain containing 7] and the nuclear factor erythroid 2-related factor 2 (NRF2) pathway [NRF2, kelch-like ECH-associated protein 1 (KEAP1), AKT and PIK3-catalytic subunit α]. Tumor samples from patients diagnosed with various stages of CC, including cervical intraepithelial neoplasia (CIN) 1, CIN 2, CIN 3, in situ CC and invasive CC, were analyzed. The mRNA expression levels were analyzed using reverse transcription-quantitative PCR assays, whereas protein expression levels were assessed through immunohistochemical tissue microarrays. High mRNA expression levels of c-MYC and AKT and low expression levels of NRF2 and KEAP1 were associated with a decreased survival time of patients with CC. Additionally, increased expression levels of c-MYC were detected in the invasive CC stage. At the protein level, increased NRF2 expression levels were observed in all five stages of CC samples compared with those in the cancer-free control samples. AKT1 was found to be dysregulated in the CIN 1 and CIN 2 stages, PI3K in the in situ and invasive stages, and CREBBP in the CIN 3 and in situ stages. In summary, the present study demonstrated significant changes in proteins of the Notch and NRF2 pathways in CC. NRF2 was overexpressed in all cervical cancer stages (cervical intraepithelial neoplasia, in situ CC and invasive CC). The present study makes an important contribution to the possible biomarker proteins to be analyzed for the presence of premalignant and malignant lesions in the cervix.

The Indigenous Probiotic Lactococcus lactis PH3-05 Enhances the Growth, Digestive Physiology, and Gut Microbiota of the Tropical Gar (Atractosteus tropicus) Larvae.

Probiotics in aquaculture hold promise for enhancing fish health and growth. Due to their increased specificity and affinity for their host, indigenous probiotics may offer isolated and potentially amplified benefits. This study investigated the effects of Lactococcus lactis PH3-05, previously isolated from adults of tropical gar (Atractosteus tropicus), on the growth, survival, digestive enzyme activity, intestinal morphology, expression of barrier and immune genes, and intestinal microbiota composition in the larvae of tropical gar. Larvae were fed with live L. lactis PH3-05 concentrations of 104, 106, and 108 CFU/g for 15 days alongside a control diet without probiotics. Higher concentrations of L. lactis PH3-05 (106 and 108 CFU/g) positively influenced larval growth, increasing hepatocyte area and enterocyte height. The 106 CFU/g dose significantly enhanced survival (46%) and digestive enzyme activity. Notably, the 108 CFU/g dose stimulated increased expression of muc-2 and il-10 genes, suggesting enhanced mucosal barrier function and anti-inflammatory response. Although L. lactis PH3-05 did not significantly change the diversity, structure, or Phylum level composition of intestinal microbiota, which was constituted by Proteobacteria, Bacteroidota, Chloroflexi, and Firmicutes, an increase in Lactobacillus abundance was observed in fish fed with 106 CFU/g, suggesting enhanced probiotic colonization. These results demonstrate that administering L. lactis PH3-05 at 106 CFU/g promotes growth, survival, and digestive health in A. tropicus larvae, establishing it as a promising indigenous probiotic candidate for aquaculture applications.

Heat stress affects milk yield, milk quality, and gene expression profiles in mammary cells of Girolando cows.

Heat stress during lactation affects the physiological responses, hormonal release, health, and productivity of dairy cows. However, the adverse effects of heat stress on milk synthesis, immune response, and cellular apoptosis in mammary cells remains unknown in Bos indicus cows. This study aimed to understand the relationship between milk yield, milk quality, and the expression of genes related to milk synthesis, cell apoptosis, and immune response in mammary cells of Girolando cows. Twenty-four Girolando cows (3/4 Holstein and 1/4 Gir) were subjected to control (CT, with a temperature-humidity index ranging from 60 to 74, n = 12) or heat stress treatments (HS, with a temperature- humidity index ranging from 60 to 85, n = 12), from 111 to 120 d of lactation. Heat stress significantly increased the expression of heat shock proteins (HSPD1 and HSPD90AA1), insulin receptors (INSR), and prolactin receptors (PRLRsf) genes, and decreased the expression of glucocorticoid receptor (NR3C1) gene in mammary cells of the HS cows when compared with the CT cows. The HS cows exhibited significantly higher vaginal temperatures and cortisol release compared with the CT cows. Moreover, the HS cows had significantly lower dry matter intake and milk yield than CT cows. Although, HS cows showed higher percentage of lymphocytes in milk when compared with that from CT cows. There was no effect of heat stress on other leukocyte counts, somatic cell counts, bacterial counts in milk, or milk composition. Finally, this study demonstrated that Girolando cows are susceptible to heat stress, which decreases milk yield and affects the expression of genes linked to milk synthesis in the mammary cells.

Novel Candidate Genes Involved in an Initial Stage of White Striping Development in Broiler Chickens.

White striping (WS) is a myopathy characterized by the appearance of white stripes parallel to the muscle fibers in the breast of broiler chickens, composed of adipose and connective tissues. This condition causes economic losses and, although common, its etiology remains poorly understood. Hence, the objective was to identify genes and biological mechanisms involved in the early stages of WS using a paternal broiler line that grows slightly slower than commercial ones, at 35 days of age, through the RNA sequencing of the pectoralis major muscle. Thirty genes were differentially expressed between normal and WS-affected chickens, with 23 upregulated and 7 downregulated in the affected broilers. Of these, 14 genes are novel candidates for WS and are implicated in biological processes related to muscle development (CEPBD, DUSP8, METTL21EP, NELL2, and UBE3D), lipid metabolism (PDK4, DDIT4, FKBP5, DGAT2, LIPG, TDH, and RGCC), and collagen (COL4A5 and COL4A6). Genes related to changes in muscle fiber type and the processes of apoptosis, autophagy, proliferation, and differentiation are possibly involved with the initial stage of WS development. In contrast, the genes linked to lipid metabolism and collagen may have their expression altered due to the progression of the myopathy.

Photodynamic therapy on mRNA levels in bacteria.

Antimicrobial photodynamic therapy (aPDT) has shown efficacy in inactivating different bacterial species by photosensitizer-induced free radical production. Despite aPDT is considered unable to cause resistant strains, enzymatic pathways for detoxification of reactive oxygen species and transmembrane photosensitizer efflux systems could cause resistance to aPDT. Resistance mechanisms can be evaluated by measurement of mRNA from by quantitative reverse transcription polymerase chain reaction (RT-qPCR). Thus, the aim of this study was to access the mRNA level data obtained by RT-qPCR in bacterial cells submitted to photodynamic therapy. Studies performed on mRNA levels in bacteria after PDT were assessed on MEDLINE/Pubmed. The mRNA levels from genes related to various functions have been successfully evaluated in both Gram-positive and -negative bacteria after aPDT by RT-qPCR. Such an approach has improved the understanding of aPDT-induced effects, and reinforced the effectiveness of aPDT on bacteria, which can cause infections in different human tissues.

In Silico Evaluation of Lawsonia intracellularis Genes Orthologous to Genes Associated with Pathogenesis in Other Intracellular Bacteria.

Proliferative enteropathy is an enteric disease caused by the bacterium Lawsonia intracellularis, which affects several species of domestic and wild animals. The mechanisms underlying the mechanisms employed by L. intracellularis to cause host cell proliferation are poorly understood, mostly because this bacterium is extremely difficult to isolate and propagate in vitro. Comparative genomics methods for searching for genes orthologous to genes known to be associated with pathogenesis allow identification of genes potentially involved in pathogenesis by the pathogen of interest. The goal of this study was to carry out in silico research on L. intracellularis genes orthologous to genes required for intracellular invasion and survival present in other pathogenic bacteria, particularly Brucella abortus, B. melitensis, B. suis, Listeria monocytogenes, Mycobacterium tuberculosis, Mycobacterium avium subspecies paratuberculosis, Salmonella enterica, Yersinia pestis, Y. enterocolitica, and Y. pseudotuberculosis. A total of 127 genes associated with invasion and intracellular survival from five known intracellular bacteria were mapped against the predicted proteomes of all L. intracellularis strains publicly available on GenBank, using the OrthoFinder program. A total of 45 L. intracellularis genes were orthologous to genes associated with pathogenesis of other intracellular bacteria. Genes putatively associated with signal the transduction of chemotaxis and cell motility were identified. Genes related to DNA binding and repair were also identified, with some of them supporting a possible association of bacteria with macrophages or inducing pro-inflammatory responses. The homology-based identification of these genes suggests their potential involvement in the virulence and pathogenicity of L. intracellularis, opening avenues for future research and insights into the molecular mechanisms of Lawsonia-elicited proliferative enteropathy.

Daily rhythm in feeding behavior and digestive processes in totoaba (Totoaba macdonaldi) under commercial farming conditions.

To identify daily changes in the digestive physiology of Totoaba macdonaldi, the feed intake, activity (pepsin, trypsin, chymotrypsin, lipase, amylase, and L-aminopeptidase), and gene expression (aminopeptidase and maltase-glucoamylase) of key digestive enzymes were measured in the intestine and the pyloric caeca. Fish were fed for three weeks every four hours during the light period to apparent satiation, and samples were taken every four hours throughout a 24-h cycle under a 12:12 L:D photoperiod. The feed consumption steadily increased until the third feeding (16:00 h, ZT-8) and decreased significantly towards the end of the day. The activity of pepsin and alkaline enzymes (trypsin, chymotrypsin, lipase, amylase, and L-aminopeptidase) exhibited a pattern dependent on the presence of feed, showing a significant reduction during the hours of darkness (ZT-12 to ZT-24). Expression of the intestinal brush border enzyme (L-aminopeptidase) increased during the darkness period in anticipation of the feed ingestion associated with the subsequent light period. The cosinor analysis used to estimate the feed rhythms for all tested enzymes showed that activity in the intestine and pyloric caeca exhibited significant rhythmicity (p < 0.05). However, no rhythmicity was observed in the intestinal expression of maltase-glucoamylase. Our results demonstrate that some of the behavioral and digestive physiology features of totoaba directly respond to rhythmicity in feeding, a finding that should be considered when establishing optimized feeding protocols.

Food contamination with fipronil alters gene expression associated with foraging in Africanized honey bees.

Taking into consideration that bees can be contaminated by pesticides through the ingestion of contaminated floral resources, we can utilize genetic techniques to assess effects that are scarcely observed in behavioral studies. This study aimed to investigate the genetic effects of ingesting lethal and sublethal doses of the insecticide fipronil in foraging honey bees during two periods of acute exposure. Bees were exposed to fipronil through contaminated honey syrup at two dosages (LD50 = 0.19 µg/bee; LD50/100 = 0.0019 µg/bee) and for two durations (1 and 4 h). Following exposure, we measured syrup consumption per bee, analyzed the transcriptome of bee brain tissue, and identified differentially expressed genes (DEGs), categorizing them functionally based on gene ontology (GO). The results revealed a significant genetic response in honey bees after exposure to fipronil, regardless of the dosage used. Fipronil affected various metabolic, transport, and cellular regulation pathways, as well as detoxification processes and xenobiotic substance detection. Additionally, the downregulation of several DEGs belonging to the olfactory-binding protein (OBP) family was observed, suggesting potential physiological alterations in bees that may lead to disoriented behaviors and reduced foraging efficiency.

Replacement Nellore heifers receiving supplementation under different herbage allowance: effects on forage characteristics, performance, physiology, and reproduction.

In Brazil, heifers typically calve at 36-48 months. Due to the high demand for meat and the need to reduce slaughter age, high supplementation has become commonly used in beef cattle farming. However, the literature remains scarce on studies that explore the impact of grazing management during the background phase on the productivity and reproductive efficiency of young Nellore heifers. This study aimed to evaluate the effects of two-herbage allowances (HA) on forage characteristics, performance, physiology and reproductive parameters of replacement Nellore heifers. Ninety weaned heifers [169 ± 19 kg of shrunk body weight (SBW); 210 ± 28 days of age] were blocked by initial BW and randomly assigned to receive different HA: (1) High herbage allowance (HHA: 7.2 kg DM/kg BW) and (2) Low herbage allowance (LHA: 3.3 kg DM/kg BW); and divided into six paddocks, totaling 12 paddocks. The experimental period was divided into the growing phase (D173) and the reproductive season (D83). Continuous stocking with a variable stocking rate was used. The supplement was provided daily with expected intake of around 10 g/kg of BW. The HHA pasture showed greater values of canopy height, greater HA, and lower values of CP and CP: in vitro digestible DM ratio than the LHA pasture over the days of the study (P ≤ 0.05). Herbage mass and the green stem proportion were lower in LHA pasture (P < 0.01), while the green leaf (g/kg DM) and senescent stem proportions (g/kg DM) were higher (P = 0.080) when compared to HHA pasture. Heifers maintained on HHA pasture had a higher average daily gain (P < 0.01), forage intake (P < 0.003), higher SBW (P < 0.01), Longissimus area (P < 0.01), and 12th-rib fat thickness (P < 0.01) than those kept in the LHA pasture. The proportion of heifers that reached the weight at maturity on D173 (P = 0.027) and the proportion of pubertal pregnancy heifers (P = 0.042) were greatest in the HHA treatment. The blood urea nitrogen (P = 0.002) was higher in heifers maintained in the LHA pasture. Heifers maintained in HHA pasture showed higher values of relative abundance of mRNA for UGT1A6 (P = 0.004) and IGFBP3 (P = 0.072). The use of HHA criteria increased forage intake, body gain, and carcass attributes of animals, which led to better reproductive performance of Nellore heifers.