Whole-mount immunofluorescent labeling of the adult fly retina.

The adult Drosophila compound eye is an ideal in vivo model for studying biological questions. However, light microscopy of this tissue requires cumbersome embedding and sectioning. Here, we document detailed whole-mount procedures for immunolabeling the adult retina, enabling high-quality studies of fluorescent-tagged targets with straightforward preparations. We describe the steps for visualizing the nuclear lamina, membrane-associated protein, and actin-rich rhabdomere, but this robust protocol can apply to other cellular structures and target proteins. For complete details on the use and execution of this protocol, please refer to Chang et al. (2021).

Influence of Admission Time on Health Care Quality and Utilization in Patients with Stroke: Analysis for a Possible July Effect and Weekend Effect.

(1) Purpose: Undesirable health care outcomes could conceivably increase as a result of the entry of new, less experienced health care personnel into patient care during the month of July (the July effect) or as a result of the less balanced allocation of health care resources on weekends (the weekend effect). Whether these two effects were present in Taiwan's National Health Insurance (NHI) system was investigated. (2) Methods: The current study data were acquired from the NHI Research Database. The research sample comprised ≥18-year-old patients diagnosed as having a stroke for the first time from 1 January 2006 to 30 September 2012. The mortality rate within 30 days after hospitalization and readmission rate within 14 days after hospital discharge were used as health care quality indicators, whereas health care utilization indicators were the total length and cost of initial hospitalization. (3) Results: The results revealed no sample-wide July effect with regard to the four indicators among patients with stroke. However, an unexpected July effect was present among in-patients in regional and public hospitals, in which the total lengths and costs of initial hospitalization for non-July admissions were higher than those for July admissions. Furthermore, the total hospitalization length for weekend admissions was 1.06-1.07 times higher than that for non-weekend admissions; the total hospitalization length for weekend admissions was also higher than that for weekday admissions during non-July months. Thus, weekend admission did not affect the health care quality of patients with stroke but extended their total hospitalization length. (4) Conclusions: Consistent with the NHI's general effectiveness in ensuring fair, universally accessible, and high-quality health care services in Taiwan, the health care quality of patients examined in this study did not vary significantly overall between July and non-July months. However, a longer hospitalization length was observed for weekend admissions, possibly due to limitations in personnel and resource allocations during weekends. These results highlight the health care efficiency of hospitals during weekends as an area for further improvement.

Coordination through Inhibition: Control of Stabilizing and Updating Circuits in Spatial Orientation Working Memory.

Spatial orientation memory plays a crucial role in animal navigation. Recent studies of tethered Drosophila melanogaster (fruit fly) in a virtual reality setting showed that the head direction is encoded in the form of an activity bump, i.e., localized neural activity, in the torus-shaped ellipsoid body (EB). However, how this system is involved in orientation working memory is not well understood. We investigated this question using free moving flies (D. melanogaster) in a spatial orientation memory task by manipulating two EB subsystems, C and P circuits, which are hypothesized for stabilizing and updating the activity bump, respectively. To this end, we suppressed or activated two types of inhibitory ring neurons (EIP and P) which innervate EB, and we discovered that manipulating the two inhibitory neuron types produced distinct behavioral deficits, suggesting specific roles of the inhibitory neurons in coordinating the stabilization and updating functions of the EB circuits. We further elucidate the neural mechanisms underlying such control circuits using a connectome-constrained spiking neural network model.

Development of an indirect ELISA to specifically detect antibodies against African swine fever virus: bioinformatics approaches.

BACKGROUND: African swine fever (ASF), characterized by acute, severe, and fast-spreading, is a highly lethal swine infectious disease caused by the African swine fever virus (ASFV), which has caused substantial economic losses to the pig industry worldwide in the past 100 years. METHODS: This study started with bioinformatics methods and verified the epitope fusion protein method's reliability that does not rely on traditional epitope identification. Meanwhile, it will also express and purify the constructed genes through prokaryotic expression and establish antibody detection methods. RESULTS: The results indicated that the protein had good reactivity and did not cross-react with other swine diseases. The receiver-operating characteristic analysis was performed to verify the determination. The area under the receiver-operating characteristic curve was 0.9991 (95% confidence interval 0.9973 to 1.001). CONCLUSIONS: It was proved that the recombinant protein is feasible as a diagnostic antigen to distinguish ASFV and provides a new idea for ASFV antibody detection.

Cleavage of human tau at Asp421 inhibits hyperphosphorylated tau induced pathology in a Drosophila model.

Hyperphosphorylated and truncated tau variants are enriched in neuropathological aggregates in diseases known as tauopathies. However, whether the interaction of these posttranslational modifications affects tau toxicity as a whole remains unresolved. By expressing human tau with disease-related Ser/Thr residues to simulate hyperphosphorylation, we show that despite severe neurodegeneration in full-length tau, with the truncation at Asp421, the toxicity is ameliorated. Cytological and biochemical analyses reveal that hyperphosphorylated full-length tau distributes in the soma, the axon, and the axonal terminal without evident distinction, whereas the Asp421-truncated version is mostly restricted from the axonal terminal. This discrepancy is correlated with the fact that fly expressing hyperphosphorylated full-length tau, but not Asp421-cleaved one, develops axonopathy lesions, including axonal spheroids and aberrant actin accumulations. The reduced presence of hyperphosphorylated tau in the axonal terminal is corroborated with the observation that flies expressing Asp421-truncated variants showed less motor deficit, suggesting synaptic function is preserved. The Asp421 cleavage of tau is a proteolytic product commonly found in the neurofibrillary tangles. Our finding suggests the coordination of different posttranslational modifications on tau may have an unexpected impact on the protein subcellular localization and cytotoxicity, which may be valuable when considering tau for therapeutic purposes.

Demographics and medical disorders associated with smoking: a population-based study.

BACKGROUND: Few studies have investigated factors associated with smoking behaviors. In this population-based study, we investigated demographics and medical comorbid diseases to establish a prediction model for smoking behaviors by using the National Health Interview Survey (NHIS) and National Health Insurance Research Database (NHIRD). METHODS: We enrolled individuals aged ≥40 years who had participated in the NHIS in 2001, 2005, and 2009. We identified the smoking behaviors of the study participants in the NHIS. Smoking behaviors were divided into ever smokers (current smokers and ex-smokers) and nonsmokers (never smokers).We defined medical comorbid disorders of the study participants by using medical claim data from the NHIRD. We used multivariable logistic regression models to calculate the adjusted odds ratio and 95% confidence interval for variables associated with smoking. The significant variables in the multivariable model were included in the receiver operating characteristic curves (ROC) to predict the sensitivity and specificity of the model. RESULTS: In total, 26,375 participants (12,779 men and 13,596 women) were included in the analysis. The prevalence of smoking was 39.29%. The mean ages of the 16,012 nonsmokers were higher than those of the 10,363 smokers (57.86 ± 12.92 years vs. 53.59 ± 10.82 years). Men outnumbered women among smokers (68.18% vs. 31.82%). Male sex, young age and middle age, being insured categories, residence in suburban areas, and chronic obstructive pulmonary disease (COPD) were independent factors associated with smoking. The area under the ROC curve of these significant factors to predict smoking behaviors was 71.63%. CONCLUSION: Sex, age, insured categories, residence in suburban areas, and COPD were associated with smoking in people.

Antiviral activity of merimepodib against foot and mouth disease virus in vitro and in vivo.

Foot and mouth disease virus (FMDV), a member of family Picornaviridae, belongs to the genus Aphthovirus, which causes foot and mouth disease (FMD), a highly transmissible disease that affects cloven-hoof animals. In spite of the fact that efficient vaccines are available, effective antiviral molecules for FMD are needed to reduce viral infection during early stages of infection. In this study, merimepodib was found to efficiently inhibit FMDV replication in a dose-dependent manner. The 50% inhibitory concentration (IC50) of merimepodib antiviral activity against two distinct FMDV strains (O/MYA98/BY/2010 and A/GD/MM/CHA/2013) was estimated to be 7.859 and 2.876 µM, respectively, while the 50% cytotoxic concentration (CC50) of merimepodib was found to be 47.74 µM. Furthermore, treatment with 30 µg merimepodib efficiently prolonged the survival time of suckling mice infected with FMDV. Taken together, these results suggested that merimepodib has the potential to be a novel antiviral agent against FMDV.

Antiviral effect of amiloride on replication of foot and mouth disease virus in cell culture.

Recently, amiloride was shown to potently suppress Coxsackievirus B3 (CVB3) replication. In the current study, we investigated whether amiloride could also exhibit antiviral activity against foot-and-mouth disease virus (FMDV), which belongs to the same family (Picornaviridae) as CVB3. We found that amiloride exerted antiviral activity in a dose-dependent manner against two strains of FMDV in IBRS-2 cells, with slight cytotoxicity at 1000 µM. Besides, amiloride did not inhibit the attachment and entry of FMDV in IBRS-2 cells, but prevented early viral replication. These data implied that amiloride could be a promising candidate for further research as a potential antiviral drug against FMDV infection.

In Vitro and in Vivo Antiviral Activity of Mizoribine Against Foot-And-Mouth Disease Virus.

Foot-and-mouth disease (FMD) is a highly contagious viral disease of cloven-hoofed animals, which has significant economic consequences in affected countries. As the currently available vaccines against FMD provide no protection until 4-7 days post-vaccination, the only alternative method to control the spread of FMD virus (FMDV) during outbreaks is the application of antiviral agents. Hence, it is important to identify effective antiviral agents against FMDV infection. In this study, we found that mizoribine has potent antiviral activity against FMDV replication in IBRS-2 cells. A time-of-drug-addition assay demonstrated that mizoribine functions at the early stage of replication. Moreover, mizoribine also showed antiviral effect on FMDV in vivo. In summary, these results revealed that mizoribine could be a potential antiviral drug against FMDV.

Antiviral activity of brequinar against foot-and-mouth disease virus infection in vitro and in vivo.

Foot-and-mouth disease (FMD) is one of the most highly contagious animal disease that affects cloven-hoofed animals. However, the FMD vaccine does not provide effective protection until adaptive immune protection elicited by the vaccination occurs. Therefore, an alternative application of antiviral agents for inhibition of the FMD virus (FMDV) is needed. Here, we demonstrated that brequinar could exhibit antiviral activity in swine kidney cells (IBRS-2 cells) infected with two different FMDV serotypes. Subsequently, in vivo activity of brequinar was confirmed in a mouse model of infection. Specifically, brequinar at a concentration of 50 µg, provided 25% protection for 5 days following FMDV challenge. These results suggested that brequinar could be used as effective antiviral agent against FMD.

Inhibitory effects of homoharringtonine on foot and mouth disease virus in vitro.

Foot-and-mouth disease (FMD) is a highly contagious disease that affects cloven-hoof animals including cattle, swine, sheep, goats, and lots of wild species. Effectively control measures are urged needed. Here, we showed that homoharringtonine treatment exhibited a strong inhibitory effect against two different strains of FMDVs (O/MYA98/BY/2010 and A/GD/MM/2013) in swine kidney (IBRS-2) cells. Further experiments demonstrated that homoharringtonine did not affect virus attachment or entry. Using time-of-addition assays, we found that the antiviral activity of homoharringtonine occurred primarily during the early stage of infection. These results demonstrated that homoharringtonine might be an effective anti-FMDV drug. Further studies are required to explore the antiviral activity of homoharringtonine against FMDV replication in vivo.

Antiviral activity of porcine interferon omega 7 against foot-and-mouth disease virus in vitro.

Foot-and-mouth disease (FMD) is a disease of worldwide economic importance, and vaccines play an important role in preventing FMDV outbreaks. However, new control strategies are still needed since FMDV outbreaks still occur in some disease-free countries. Currently, interferon (IFN)-based strategies have been demonstrated to be an efficient biotherapeutic option against FMDV; however, interferon omega (IFN-ω) has not yet been assessed in this capacity. Thus, this study evaluated the antiviral activity of porcine IFN omega 7 (PoIFN-ω7) against FMDV. After the PoIFN-ω7 was expressed and purified, cell proliferation assays and quantitative real-time reverse transciption-polymerase chain reaction were used to evaluate the effective anti-cytopathic concentration of PoIFN-ω7 and its effectiveness pre- and post-infection with FMDV in swine kidney cells (IBRS-2). Results showed the rHis-PoIFN-ω7 fusion protein was considerably expressed using Escherichia coli BL21 (DE3) strain, and the recombinant protein exhibited significant in vitro protection against FMDV, including two strains belonging to type O and A FMDV, respectively. In addition, PoIFN-ω7 upregulated the transcription of Mx1, ISG15, OAS1, and PKR genes. These findings indicated that IFN-ω has the potential for serving as a useful therapeutic agent to prevent FMDV or other viral outbreaks in pigs.

A novel type I interferon, interferon alphaomega, shows antiviral activity against foot-and-mouth disease virus in vitro.

Recently, a novel type I interferon alphaomega (IFN-αω), also known as IFN-µ, was identified. However, the biological activity of IFN-αω remain poorly understood. In this study, the porcine IFN-αω (PoIFN-αω) was expressed, purified, and its antiviral activities assessed by its ability to inhibit the cytopathic effect caused by FMDV on IBRS-2 cells. In addition, q-PCR was used to evaluate the expression of IFN-stimulated genes induced by PoIFN-αω. It was found that PoIFN-αω exerted effective antiviral activity against FMDV pre- and post-infection. Additionally, PoIFN-αω induced the transcription of IFN-stimulated genes, including Mx1, ISG15, OAS1, and PKR genes. Our study reported a new indication of PoIFN-αω as an effective anti-FMDV agent for the first time.

Type I Interferons: Distinct Biological Activities and Current Applications for Viral Infection.

The interferons (IFNs) are a primary defense against pathogens because of the strong antiviral activities they induce. IFNs can be classified into three groups: type I, type II and type III, according to their genetic, structural, and functional characteristics and their receptors on the cell surface. The type I IFNs are the largest group and include IFN-α, IFN-ß, IFN-ε, IFN-ω, IFN-κ, IFN-δ, IFN-τ and IFN-ζ. The use of IFNs for the treatment of viral infectious diseases on their antiviral activity may become an important therapeutic option, for example, IFN-α is well known for the successful treatment of hepatitis B and C virus infections, and interest is increasing in the antiviral efficacy of other novel IFN classes and their potential applications. Therefore, in this review, we summarize the recent progress in the study of the biological activities of all the type I IFN classes and their potential applications in the treatment of infections with immunodeficiency virus, hepatitis viruses, and influenza viruses.

Neuronal Cell Death Mechanisms in Major Neurodegenerative Diseases.

Neuronal cell death in the central nervous system has always been a challenging process to decipher. In normal physiological conditions, neuronal cell death is restricted in the adult brain, even in aged individuals. However, in the pathological conditions of various neurodegenerative diseases, cell death and shrinkage in a specific region of the brain represent a fundamental pathological feature across different neurodegenerative diseases. In this review, we will briefly go through the general pathways of cell death and describe evidence for cell death in the context of individual common neurodegenerative diseases, discussing our current understanding of cell death by connecting with renowned pathogenic proteins, including Tau, amyloid-beta, alpha-synuclein, huntingtin and TDP-43.

Untangling the Tauopathy for Alzheimer's disease and parkinsonism.

Tau is a microtubule-associated protein that mainly localizes to the axon to stabilize axonal microtubule structure and neuronal connectivity. Tau pathology is one of the most common proteinopathies that associates with age-dependent neurodegenerative diseases including Alzheimer's disease (AD), and various Parkinsonism. Tau protein undergoes a plethora of intra-molecular modifications and some altered forms promote the production of toxic oligomeric tau and paired helical filaments, and through which further assemble into neurofibrillary tangles, also known as tauopathy. In this review, we will discuss the recent advances of the tauopathy research, primarily focusing on its association with the early axonal manifestation of axonal transport defect, axonal mitochondrial stress, autophagic vesicle accumulation and the proceeding of axon destruction, and the pathogenic Tau spreading across the synapse. Two alternative strategies either by targeting tau protein itself or by improving the age-related physiological decline are currently racing to find the hopeful treatment for tauopathy. Undoubtedly, more studies are needed to combat this devastating condition that has already affected millions of people in our aging population.

Antiviral activity of porcine interferon delta 8 against foot-and-mouth disease virus in vitro.

Foot-and-mouth disease (FMD) is one of the most devastating diseases affecting livestock. Since vaccines fail to provide protection until seven days post-vaccination, the application of anti-viral molecules is imperative for suppressing the spread of FMDV prior to development of an adaptive immune response. Interferons (IFNs) are effective for the host to fight FMDV infections; however, a novel type I IFNs, interferon delta (IFN-δ), has not been investigated for their antiviral effects against this virus. Thus, this study investigated FMDV infection, upon pre- and post-treatment with PoIFN-δ8. Real-time quantitative PCR was used to quantify the expression levels of IFN-stimulated genes (ISGs), including ISG15, OAS1, PKR, and Mx1. Results showed the PoIFN-δ8 lacking its signal sequence was efficiently expressed in Escherichia coli, and the purified recombinant PoIFN-δ8 exerted a significantly protective effect against two different serotypes of FMDV in IBRS-2 cells. In addition, PoIFN-δ8 induced the expression of IFN-stimulated genes. These findings highlight the significance of PoIFN-δ might serve as an antiviral agent for the prevention of FMDV in pigs and will stimulate the study of exploiting the potential biological functions of IFN-δ in the future.

Development of a New RT-PCR with Multiple Primers for Detecting Southern African Territories Foot-and-mouth Disease Viruses.

INTRODUCTION: The extremely high genetic variation and the continuously emerging variants of foot-and-mouth disease virus (FMDV) of Southern African Territory (SAT) serotypes including SAT1, SAT2, and SAT3 make it necessary to develop a new RT-PCR for general use for monitoring viruses based on the updated genome information. MATERIAL AND METHODS: A FMDV SAT-D8 one-step RT-PCR was established based on the 1D2A2B genes of the SAT serotype viruses with a multiplex primer set. FMDV A, O, C, and Asia 1 serotypes, other vesicular disease viruses, inactivated SAT viruses, and 125 bovine, ovine, caprine and porcine tissue samples collected from the Chinese mainland were included for evaluating the assay. RESULTS: The new RT-PCR was proven to be specific without cross-reactions with Eurasian FMDV, swine vesicular disease virus (SVDV), Seneca valley virus (SVV), or other common viral pathogens of cattle, sheep, goat, and pig. An around 257 bp-sized amplicon clearly appeared when the inactivated SAT viruses were detected. However, all 125 samples collected from FMDV-susceptible animals from the Chinese mainland which has not known SAT epidemics showed negative results. CONCLUSIONS: A FMDV SAT-D8 one-step RT-PCR is a promising method for primary screening for FMDV SAT serotypes.

Interferon-omega: Current status in clinical applications.

Since 1985, interferon (IFN)-ω, a type I IFN, has been identified in many animals, but not canines and mice. It has been demonstrated to have antiviral, anti-proliferation, and antitumor activities that are similar to those of IFN-α. To date, IFN-ω has been explored as a treatment option for some diseases or viral infections in humans and other animals. Studies have revealed that human IFN-ω displays antitumor activities in some models of human cancer cells and that it can be used to diagnose some diseases. While recombinant feline IFN-ω has been licensed in several countries for treating canine parvovirus, feline leukemia virus, and feline immunodeficiency virus infections, it also exhibits a certain efficacy when used to treat other viral infections or diseases. This review examines the known biological activity of IFN-ω and its clinical applications. We expect that the information provided in this review will stimulate further studies of IFN-ω as a therapeutic agent.

Vps35 in cooperation with LRRK2 regulates synaptic vesicle endocytosis through the endosomal pathway in Drosophila.

Mutations of the retromer component Vps35 and endosomal kinase LRRK2 are linked to autosomal dominant forms of familial Parkinson's disease (PD). However, the physiological and pathological roles of Vps35 and LRRK2 in neuronal functions are poorly understood. Here, we demonstrated that the loss of Drosophila Vps35 (dVps35) affects synaptic vesicle recycling, dopaminergic synaptic release and sleep behavior associated with dopaminergic activity, which is rescued by the expression of wild-type dVps35 but not the PD-associated mutant dVps35 D647N. Drosophila LRRK2 dLRRK together with Rab5 and Rab11 is also implicated in synaptic vesicle recycling, and the manipulation of these activities improves the Vps35 synaptic phenotypes. These findings indicate that defects of synaptic vesicle recycling in which two late-onset PD genes, Vps35 and LRRK2, are involved could be key aspects of PD etiology.