The gyrfalcon (Falco rusticolus) genome.

High-quality genome assemblies are characterized by high-sequence contiguity, completeness, and a low error rate, thus providing the basis for a wide array of studies focusing on natural species ecology, conservation, evolution, and population genomics. To provide this valuable resource for conservation projects and comparative genomics studies on gyrfalcon (Falco rusticolus), we sequenced and assembled the genome of this species using third-generation sequencing strategies and optical maps. Here, we describe a highly contiguous and complete genome assembly comprising 20 scaffolds and 13 contigs with a total size of 1.193 Gbp, including 8,064 complete Benchmarking Universal Single-Copy Orthologs (BUSCOs) of the total 8,338 BUSCO groups present in the library aves_odb10. Of these BUSCO genes, 96.7% were complete, 96.1% were present as a single copy, and 0.6% were duplicated. Furthermore, 0.8% of BUSCO genes were fragmented and 2.5% (210) were missing. A de novo search for transposable elements (TEs) identified 5,716 TEs that masked 7.61% of the F. rusticolus genome assembly when combined with publicly available TE collections. Long interspersed nuclear elements, in particular, the element Chicken-repeat 1 (CR1), were the most abundant TEs in the F. rusticolus genome. A de novo first-pass gene annotation was performed using 293,349 PacBio Iso-Seq transcripts and 496,195 transcripts derived from the assembly of 42,429,525 Illumina PE RNA-seq reads. In all, 19,602 putative genes, of which 59.31% were functionally characterized and associated with Gene Ontology terms, were annotated. A comparison of the gyrfalcon genome assembly with the publicly available assemblies of the domestic chicken (Gallus gallus), zebra finch (Taeniopygia guttata), and hummingbird (Calypte anna) revealed several genome rearrangements. In particular, nine putative chromosome fusions were identified in the gyrfalcon genome assembly compared with those in the G. gallus genome assembly. This genome assembly, its annotation for TEs and genes, and the comparative analyses presented, complement and strength the base of high-quality genome assemblies and associated resources available for comparative studies focusing on the evolution, ecology, and conservation of Aves.

Digestive Enzyme Activities, Oxidative Status and Intestinal Histomorphometry of Rats Supplemented with Steviana, A Natural Sweetener.

<b>Background and Objective:</b> Stevia (<i>Stevia rebaudiana</i>), often known as sweet leaf, is a perennial plant and a member of the Asteraceae family. The commercial version of stevia leaf powder, known as Steviana, is one of the most popular natural sweeteners in use today. The current study aimed to analyze the activities of gut digestive enzymes, intestinal oxidative state and intestinal histological structure in stevia-fed rats. <b>Materials and Methods:</b> In this study, male rats were given Steviana and the oxidative condition of the gastrointestinal tract (GIT), the activities of certain digestive enzymes and the histomorphology of the GIT were examined. Animals used in experiments were split into 2 groups: Control and treated groups. For four consecutive weeks, the treatment group received a daily oral intake of 5 mg kg¹ b.wt., of Steviana solution. At the end of the trial, serum, pancreas and intestinal tissue samples were taken. <b>Results:</b> The Steviana sweetener has a strong antioxidative effect on both blood and intestinal tissue. Both sample types showed a decrease in malondialdehyde levels and a marked increase in superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities compared to control samples. In samples of blood, pancreas and intestinal contents, the activities of digestive enzymes including α-amylase, lipase and protease were significantly elevated in Steviana-treated rats. In addition, histological analysis of the small intestine showed that in rats given Steviana sweetener, intestinal glandular crypt depth was more pronounced compared to the control animals. <b>Conclusion:</b> In summary, consumption of Steviana appears to enhance digestion and absorption processes through antioxidative effects, improving the health of the local GIT and subsequently accelerating the rate of synthesis and release of endogenous digestive enzymes. Another aspect that enhances the digestion and absorption process is the change in the histological structure of the intestinal glands, as shown by an increase in the crypt depth.

LRP6 Receptor Plays Essential Functions in Development and Human Diseases.

LRP6 is a member of the low-density lipoprotein receptor superfamily of cell-surface receptors. It is required for the activation of the Wnt/ß-catenin signalling pathway. LRP6 is detected in different tissue types and is involved in numerous biological activities such as cell proliferation, specification, metastatic cancer, and embryonic development. LRP6 is essential for the proper development of different organs in vertebrates, such as Xenopus laevis, chickens, and mice. In human, LRP6 overexpression and mutations have been reported in multiple complex diseases including hypertension, atherosclerosis, and cancers. Clinical studies have shown that LRP6 is involved in various kinds of cancer, such as bladder and breast cancer. Therefore, in this review, we focus on the structure of LRP6 and its interactions with Wnt inhibitors (DKK1, SOST). We also discuss the expression of LRP6 in different model systems, with emphasis on its function in development and human diseases.

Assessment of health awareness and knowledge toward SARS-CoV-2 and COVID-19 vaccines among residents of Makkah, Saudi Arabia.

INTRODUCTION: Public awareness regarding COVID-19 plays an important role in controlling the virus' spread and treating infected people. A high level of awareness among the public will help to implement preventive measures, particularly in the most populated regions, such as Makkah, Saudi Arabia. COVID-19 is an infectious disease and the Saudi Arabian government has taken serious precautions and implemented several preventive measures. In addition, The Ministry of Health (MOH) has launched many awareness campaigns and provided COVID-19 vaccines for free. THE OBJECTIVES: To assess the Public's level of health awareness and knowledge toward SARS-CoV-2 and COVID-19 vaccines among residents of Makkah, Saudi Arabia. METHODS: A cross-sectional study was conducted in the Makkah region from February 23 to March 2, 2021. The questionnaire was generated using a Google form and distributed online through social platforms such as Twitter and WhatsApp. The questionnaire consisted of five sections and six hundred participants have answered and completed all questions. Then, All data were imported into Microsoft Excel and analyzed using the statistical tools SAS version 9.4 and SPSS version 25 software. RESULTS: A total of 600 participants from the Makkah region were found to have a high level of awareness and knowledge about all aspects of SARS-CoV-2 and the COVID-19 disease. For example, all participants considered coronavirus to be contagious, and 89.8% of them knew that COVID-19's symptoms are similar to those of seasonal flu. Most respondents showed a high level of awareness regarding the main factors of SARS-CoV-2 transmission. Over 98.7% of respondents were aware of the role of gatherings and events in further spread of the virus. The participants showed a good level of awareness about other preventive measures, such as maintaining social distancing and wearing a mask. However, the respondents considered COVID-19 vaccines to be effective, but some of them were not aware of their side effects, and 38.8% planned to receive a vaccine. CONCLUSION: The residents of Makkah showed a high level of awareness about these aspects; an excellent awareness level was noted for SARS-CoV-2, means of transmission, disease symptoms and prevention of viral spread. On the other hand, the participants had less knowledge regarding COVID-19 vaccines; hence, more effort is required to educate people about the safety and benefits of the vaccines.

Unraveling the Catha edulis Extract Effects on the Cellular and Molecular Signaling in SKOV3 Cells.

Khat (Catha edulis (Vahl) Endl.) is an evergreen flowering shrub used as a stimulant in many regions worldwide including East Africa, the Arabian Peninsula, Europe, and the United States. Chewing leaves of khat induces excitement and euphoria, which are primarily attributed to two major constituents, cathinone and cathine. Khat also contains other important constituents such as cathedulins. A considerable number of studies reported side effects induced by the khat extracts to both embryos and adults. These include teratogenicity and developmental retardation, oral cancer and ulcers, high blood pressure, and myocardial infarction. So far, little attention has been paid to the effects of khat extracts on the molecular signaling interactions. We aimed in this study to investigate this through evaluating the effects of khat extracts on SKOV3, a human ovarian adenocarcinoma cell line. We show, by in vitro assays, that khat induces several cellular defects including reduced cell size, cell membrane damage, and apoptosis. At high khat extract concentrations, the cell metabolic activity, cell cycle, and cellular proliferation were affected. RT-qPCR analysis showed an increase in the gene expression of the apoptotic marker BAX, the tumor suppressor p53, and the inflammatory cytokine IL-6. Protein expression analysis by immunostaining showed downregulation of ß-catenin, E-cadherin, and Ki-67 and upregulation of FZD8 and SPRY2, suggesting that Wnt and FGF signaling were implicated. SwissTargetPrediction in silico analysis showed that khat constituents cathine, cathinone, catheduline K2, and catheduline E5 bind to family A G-protein-coupled receptor, cause many neurological diseases and disorders such as Alzheimer's, schizophrenia, depression, and anxiety, and induce many ovarian cancer-related diseases. The analysis also showed that important signaling pathways such as CREB, Wnt, FGF, IL-6, and ERK/MAPK, and that of the endometrial cancer, and cell cycle were implicated. Upstream regulators of cathine and cathinone were found to potentially target several molecules including interleukin-8, MMP2, PLAU, and micro-RNAs. In conclusion, khat induces significant cellular and molecular changes that could potentially cause a wide range of serious diseases and syndromes. Such an impact could have a heavy burden on the health care system in the countries where khat is consumed.

Expression analysis of chick Frizzled receptors during spinal cord development.

Frizzleds (Fzds) are transmembrane receptors that can transduce signals dependent upon binding of Wnts, a large family of secreted glycoproteins homologous to the Drosophila wingless gene. FZDs are critical for a wide variety of normal and pathological developmental processes. In the nervous system, Wnts and Frizzleds play an important role in anterior-posterior patterning, cell fate decisions, proliferation, and synaptogenesis. Here, we preformed a comprehensive expression profile of Wnt receptors (FZD) by using situ hybridization to identify FZDs that are expressed in dorsal-ventral regions of the neural tube development. Our data show specific expression for FZD1,2,3,7,9 and 10 in the chick developing spinal cord. This expression profile of cFZD receptors offers the basis for functional studies in the future to determine roles for the different FZD receptors and their interactions with Wnts during dorsal-ventral neural tube development in vivo. Furthermore, we also show that co-overexpression of Wnt1/3a by in vivo electroporation affects FZD7/10 expression in the neural tube. This illustrates an example of Wnts-FZDs interactions during spinal cord neurogenesis.

Molecular characterization of the Fe­hydrogenase gene marker in Trichomonas gallinae isolated from birds in Riyadh, Saudi Arabia.

Trichomonas gallinae causes avian oropharyngeal trichomonosis. This pathogen affects a large number of bird species and may cause substantial economic losses to the poultry industry. Al-Azizia poultry market in Riyadh, Saudi Arabia is among the largest poultry markets in the Arabian Gulf. Birds traded in this market may be exposed to a variety of T. gallinae strains. Genetic diversity of T. gallinae among birds in the market was examined using Fe­hydrogenase gene sequences. These sequences were amplified by PCR for twenty-nine isolates of T. gallinae from four different avian species, including 21 feral pigeons, one common mynah, three chickens, and four turkeys. Sequence analysis showed ten variant gene sequences. Nine sequences comprise a new subtype, including A(KSAF1), C(KSAF1) and C(KSAF3) with 34.48% (n = 10), 6.90% (n = 2), 6.90% (n = 2) of the isolates, respectively. Analyses also showed an additional five new sequences (KSAF1.1., KSAF2, KSAF13, KSAF14, KSAF15), representing 17.24% of the isolates. Subtype II (KSAF) was found in four feral pigeons (13.80%). To our knowledge, this report is the first to describe genotypes of T. gallinae from pigeons in Saudi Arabia using Fe­hydrogenase gene sequences for subtyping. Subtype analysis infers the presence of multiple genotypes of T. gallinae in Saudi avian populations.

FZD10 regulates cell proliferation and mediates Wnt1 induced neurogenesis in the developing spinal cord.

Wnt/FZD signalling activity is required for spinal cord development, including the dorsal-ventral patterning of the neural tube, where it affects proliferation and specification of neurons. Wnt ligands initiate canonical, ß -catenin-dependent, signaling by binding to Frizzled receptors. However, in many developmental contexts the cognate FZD receptor for a particular Wnt ligand remains to be identified. Here, we characterized FZD10 expression in the dorsal neural tube where it overlaps with both Wnt1 and Wnt3a, as well as markers of dorsal progenitors and interneurons. We show FZD10 expression is sensitive to Wnt1, but not Wnt3a expression, and FZD10 plays a role in neural tube patterning. Knockdown approaches show that Wnt1 induced ventral expansion of dorsal neural markes, Pax6 and Pax7, requires FZD10. In contrast, Wnt3a induced dorsalization of the neural tube is not affected by FZD10 knockdown. Gain of function experiments show that FZD10 is not sufficient on its own to mediate Wnt1 activity in vivo. Indeed excess FZD10 inhibits the dorsalizing activity of Wnt1. However, addition of the Lrp6 co-receptor dramatically enhances the Wnt1/FZD10 mediated activation of dorsal markers. This suggests that the mechanism by which Wnt1 regulates proliferation and patterning in the neural tube requires both FZD10 and Lrp6.

Klhl31 attenuates ß-catenin dependent Wnt signaling and regulates embryo myogenesis.

Klhl31 is a member of the Kelch-like family in vertebrates, which are characterized by an amino-terminal broad complex tram-track, bric-a-brac/poxvirus and zinc finger (BTB/POZ) domain, carboxy-terminal Kelch repeats and a central linker region (Back domain). In developing somites Klhl31 is highly expressed in the myotome downstream of myogenic regulators (MRF), and it remains expressed in differentiated skeletal muscle. In vivo gain- and loss-of-function approaches in chick embryos reveal a role of Klhl31 in skeletal myogenesis. Targeted mis-expression of Klhl31 led to a reduced size of dermomyotome and myotome as indicated by detection of relevant myogenic markers, Pax3, Myf5, myogenin and myosin heavy chain (MF20). The knock-down of Klhl31 in developing somites, using antisense morpholinos (MO), led to an expansion of Pax3, Myf5, MyoD and myogenin expression domains and an increase in the number of mitotic cells in the dermomyotome and myotome. The mechanism underlying this phenotype was examined using complementary approaches, which show that Klhl31 interferes with ß-catenin dependent Wnt signaling. Klhl31 reduced the Wnt-mediated activation of a luciferase reporter in cultured cells. Furthermore, Klhl31 attenuated secondary axis formation in Xenopus embryos in response to Wnt1 or ß-catenin. Klhl31 mis-expression in the developing neural tube affected its dorso-ventral patterning and led to reduced dermomyotome and myotome size. Co-transfection of a Wnt3a expression vector with Klhl31 in somites or in the neural tube rescued the phenotype and restored the size of dermomyotome and myotome. Thus, Klhl31 is a novel modulator of canonical Wnt signaling, important for vertebrate myogenesis. We propose that Klhl31 acts in the myotome to support cell cycle withdrawal and differentiation.