Search

Over the years, development of molecular diagnostics has evolved significantly in the detection of pathogens within humans and their surroundings. Researchers have discovered new species and strains of viruses, while mitigating the viral infections that occur, owing to the accessibility of nucleic acid screening methods such as polymerase chain reaction (PCR), quantitative (real-time) polymerase chain reaction (qPCR) and reverse-transcription qPCR (RT-qPCR). While such molecular detection methods are widely utilized as the benchmark, the invention of isothermal amplifications has also emerged as a reliable tool to improvise on-field diagnosis without dependence on thermocyclers. Among the established isothermal amplification technologies are loop-mediated isothermal amplification (LAMP), recombinant polymerase amplification (RPA), strand displacement activity (SDA), nucleic acid sequence-based amplification (NASBA), helicase-dependent amplification (HDA) and rolling circle amplification (RCA). This review highlights the past research on and future prospects of LAMP, its principles and applications as a promising point-of-care diagnostic method against avian viruses.

Gene therapy research has advanced to clinical trials, but it is hampered by unstable nucleic acids packaged inside carriers and there is a lack of specificity towards targeted sites in the body. This study aims to address gene therapy limitations by encapsidating a plasmid synthesizing a short hairpin RNA (shRNA) that targets the anti-apoptotic Bcl-2 gene using truncated hepatitis B core antigen (tHBcAg) virus-like particle (VLP). A shRNA sequence targeting anti-apoptotic Bcl-2 was synthesized and cloned into the pSilencer 2.0-U6 vector. The recombinant plasmid, namely PshRNA, was encapsidated inside tHBcAg VLP and conjugated with folic acid (FA) to produce FA-tHBcAg-PshRNA VLP. Electron microscopy revealed that the FA-tHBcAg-PshRNA VLP has an icosahedral structure that is similar to the unmodified tHBcAg VLP. Delivery of FA-tHBcAg-PshRNA VLP into HeLa cells overexpressing the folate receptor significantly down regulated the expression of anti-apoptotic Bcl-2 at 48 and 72 h post-transfection. The 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay demonstrated that the cells’ viability was significantly reduced from 89.46% at 24 h to 64.52% and 60.63%, respectively, at 48 and 72 h post-transfection. As a conclusion, tHBcAg VLP can be used as a carrier for a receptor-mediated targeted delivery of a therapeutic plasmid encoding shRNA for gene silencing in cancer cells.

Aims: Psittacine birds such as parrots, macaws, cockatoos, lovebirds and parakeets, are widely reared as household pets or at aviary due to their attractive features. However, the status of virus-causing diseases of psittacine species in Malaysia is fairly under-documented. Therefore, this study was aimed to detect the presence of three common avian viruses that infect psittacine birds, i.e. beak and feather disease virus (BFDV), avian polyomavirus and avian papillomavirus. Methodology and results: Faecal samples from twelve asymptomatic captive psittacine birds of different species were collected from an undisclosed animal garden in Serdang, Selangor, Malaysia. Briefly, the sample was homogenised and resuspended with SM buffer with the ratio 1:1 (weight of sample/g: volume of SM buffer/mL) before centrifugation at 1,000 × g for 20 min. The supernatant was collected and filtered before subjected to genomic DNA extraction using a commercialised kit. Polymerase chain reaction (PCR) technique was used to screen the V1, VP1 and L1 genes of beak and feather disease virus (BFDV), avian polyomavirus and avian papillomavirus, respectively. Findings revealed that the samples were negative for BFDV and avian polyomavirus. However, positive results of 1.5 kbp PCR amplicon were detected for avian papillomavirus in four out of the 12 samples (33.33%), which was from the white-crested cockatoo, African grey parrot, yellow-collared macaw and Senegal parrot. Sequence analysis of the L1 gene from the Senegal parrot Poicephalus senegalus revealed 93% identity to a reference Psittacus erithacus timneh avian papillomavirus. Conclusion, significance and impact of study: This study added to the limited prevalence data of three important avian viruses which infect captive psittacines in Seri Kembangan, Selangor, Malaysia. Avian papillomavirus, but not BFDV and avian polyomavirus, was detected in the collected captive psittacine birds. Therefore, a routine screening can be performed to mon

Inclusion body hepatitis (IBH) is considered one of the re-emerging diseases of avian virus that causes economic damage worldwide. IBH is caused by different serotypes of fowl adenovirus (FAdV), and most of the FAdV cases in Malaysia are related to the serotype 8b. The objective of this study was to determine the molecular markers of UPMT27 Malaysian FAdV isolate and to identify the evolutionary relationship through the phylogenetic approach. Propagation of the isolate was made in embryonated chicken eggs and chicken embryo liver (CEL cells) before it was subjected to viral DNA extraction. Both the fiber and hexon genes of the isolate were amplified and sequenced. The sequences were aligned with the published FAdV sequences. The results showed 100% identity between UPMT27 and the previous Malaysian isolates. A phylogenetic study showed that UPMT27 was closely related to the previous Malaysian isolates. Interestingly, the substitution of the amino acids was consistent between the Malaysia isolates of both fiber protein at positions 72 (Serine –serine), 101 (Alanine -alanine), 125 (Glycine-glycine), and hexon protein 85 (Serine-serine) 160 (Glutamate- glutamate) and 205 (Alanine-alanine) respectively. It appeared that the amino acid variations were the indicators for genetic diversity. Thus, these findings provide information on the evolutionary relationship between FAdV subtypes for IBH prevention.

Acute hepatopancreatic necrosis disease (AHPND) or formerly known as early mortality syndrome (EMS) is an emerging disease that has caused significant economic losses to the aquaculture industry. The primary causative agent of AHPND is Vibrio parahaemolyticus, a Gram-negative rod-shaped bacterium that has gained plasmids encoding the fatal binary toxins Pir A/Pir B that cause rapid death of the infected shrimp. In this review, the current research studies and information about AHPND in shrimps have been presented. Molecular diagnostic tools and potential treatments regarding AHPND were also included. This review also includes relevant findings which may serve as guidelines that can help for further investigation and studies on AHPND or other shrimp diseases.

In comparison to the extensive characterization of haemagglutinin antibodies of avian influenza virus (AIV), the role of neuraminidase (NA) as an immunogen is less well understood. This study describes the construction and cellular responses of recombinant fowlpox viruses (rFWPV) strain FP9, co-expressing NA N1 gene of AIV A/Chicken/Malaysia/5858/2004, and chicken IL-12 gene. Our data shows that the N1 and IL-12 proteins were successfully expressed from the recombinants with 48 kD and 70 kD molecular weights, respectively. Upon inoculation into specific-pathogen-free (SPF) chickens at 105 p.f.u. ml−1, levels of CD3+/CD4+ and CD3+/CD8+ populations were higher in the wild-type fowlpox virus FP9 strain, compared to those of rFWPV-N1 and rFWPV-N1-IL-12 at weeks 2 and 5 time points. Furthermore, rFWPV-N1-IL-12 showed a suppressive effect on chicken body weight within 4 weeks after inoculation. We suggest that co-expression of N1 with or without IL-12 offers undesirable quality as a potential AIV vaccine candidate.

Nanoparticles (NPs) have emerged as a powerful drug-delivery tool for cancer therapies to enhance the specificity of drug actions, while reducing the systemic side effects. Nonetheless, NPs interact massively with the surrounding physiological environments including plasma proteins upon administration into the bloodstream. Consequently, they are rapidly cleared from the blood circulation by the mononuclear phagocyte system (MPS) or complement system, resulting in a premature elimination that will cause the drug release at off-target sites. By grafting a stealth coating layer onto the surface of NPs, the blood circulation half-life of nanomaterials can be improved by escaping the recognition and clearance of the immune system. This review focuses on the basic concept underlying the stealth behavior of NPs by polymer coating, whereby the fundamental surface coating characteristics such as molecular weight, surface chain density as well as conformations of polymer chains are of utmost importance for efficient protection of NPs. In addition, the most commonly used stealth polymers such as poly(ethylene glycol) (PEG), poly(2-oxazoline) (POx), and poly(zwitterions) in developing long-circulating NPs for drug delivery are also thoroughly discussed. The biomimetic strategies, including the cell-membrane camouflaging technique and CD47 functionalization for the development of stealth nano-delivery systems, are highlighted in this review as well.

Epizootics of highly pathogenic avian influenza (HPAI) have resulted in the deaths of millions of birds leading to huge financial losses to the poultry industry worldwide. The roles of migratory wild birds in the harbouring, mutation, and transmission of avian influenza viruses (AIVs), and the lack of broad-spectrum prophylactic vaccines present imminent threats of a global panzootic. To prevent this, control measures that include effective AIV surveillance programmes, treatment regimens, and universal vaccines are being developed and analysed for their effectiveness. We reviewed the epidemiology of AIVs with regards to past avian influenza (AI) outbreaks in birds. The AIV surveillance programmes in wild and domestic birds, as well as their roles in AI control were also evaluated. We discussed the limitations of the currently used AI vaccines, which necessitated the development of a universal vaccine. We evaluated the current development of AI vaccines based upon virus-like particles (VLPs), particularly those displaying the matrix-2 ectodomain (M2e) peptide. Finally, we highlighted the prospects of these VLP vaccines as universal vaccines with the potential of preventing an AI panzootic.

This study was conducted to evaluate the effects of stingless bee honey (SBH) supplementation on memory and learning in mice. Despite many studies that show the benefits of honey on memory, reports on the nootropic effects of SBH are still lacking, and their underlying mechanism is still unclear. SBH is a honey produced by the bees in the tribe of Meliponini that exist in tropical countries. It features unique storage of honey collected in cerumen pots made of propolis. This SBH may offer a better prospect for therapeutic performance as the previous report identifies the presence of antioxidants that were greater than other honey produced by Apis sp. In this study, SBH was tested on Swiss albino mice following acute (7 days) and semichronic (35 days) supplementation. Experiments were then conducted using Morris water maze (MWM) behaviour analysis, RT-PCR for gene expression of mice striatum, and NMR for metabolomics analysis of the honey. Results indicate spatial working memory and spatial reference memory of mice were significantly improved in the honey-treated group compared with the control group. Improved memory consolidations were also observed in prolonged supplementation. Gene expression analyses of acutely treated mice demonstrated significant upregulation of BDNF and Itpr 1 genes that involve in synaptic function. NMR analysis also identified phenylalanine, an essential precursor for tyrosine that plays a role at the BDNF receptor. In conclusion, SBH supplementation for seven days at 2000 mg/kg, which is equivalent to a human dose of 162 mg/kg, showed strong capabilities to improve spatial working memory. And prolonged intake up to 35 days increased spatial reference memory in the mice model. The phenylalanine in SBH may have triggered the upregulation of BDNF genes in honey-treated mice and improved their spatial memory performance.

Fowlpox virus (FWPV) has been used as a recombinant vaccine vector to express antigens from several important avian pathogens. Attempts have been made to improve vaccine strains induced-host immune responses by coexpressing cytokines. This study describes the construction of recombinant FWPV (rFWPV) strain FP9 and immunological responses in specific-pathogen-free (SPF) chickens, co-expressing avian influenza virus (AIV) H5 of A/Chicken/Malaysia/5858/2004, and chicken IL-15 cytokine genes. Expression of H5 (50 kD) was confirmed by western blotting. Anti-H5 antibodies, which were measured by the haemagglutinin inhibition test, were at the highest levels at Week 3 post-inoculation in both rFWPV/H5- and rFWPV/H5/IL-15-vaccinated chickens, but decreased to undetectable levels from Week 5 onwards. CD3+/CD4+ or CD3+/CD8+T cell populations, assessed using flow cytometry, were significantly increased in both WT FP9- and rFWPV/H5-vaccinated chickens and were also higher than in rFWPV/H5/IL-15- vaccinated chickens, at Week 2. Gene expression analysis using real time quantitative polymerase chain reaction (qPCR) demonstrated upregulation of IL-15 expression in all vaccinated groups with rFWPV/H5/IL-15 having the highest fold change, at day 2 (117±51.53). Despite showing upregulation, fold change values of the IL-18 expression were below 1.00 for all vaccinated groups at day 2, 4 and 6. This study shows successful construction of rFWPV/H5 co-expressing IL-15, with modified immunogenicity upon inoculation into SPF chickens.

Stingless bees are in a diverse group of highly eusocial bees (meliponines) which are reared for their products and pollination potentials. The main source of stingless bee colonies is depending on feral colony hunting that potentially affects the ecosystem. Therefore, establishment of a good practise in colony transfer and splitting may extend the survival of a colony in a new location. This study describes a colony transfer strategy from log to hive and nest characteristics of stingless bee Heterotrigoma itama upon colony splitting from the hive. All 15 colonies from the hollow trunks of trees could survive after one month of transfer to hives. Pre-colony splitting data of 10 daughter colonies showed that the height of brood cells was 14.5 ± 1.20 cm, the number of brood layer was 8.9 ± 2.13, while the number of queen cell was 5.2 ± 1.32. After 12 weeks, the height of brood cells became 16.42 ± 1.05 cm, while the numbers of brood layer and virgin queen eggs were increased to 12.1 ± 1.85 and 6.4 ± 1.65, respectively. However, the correlation between the number of brood layer and virgin queen egg was significantly low (r = 0.421). These results show the ideal strategy for colony transfer from log and colony splitting, and the number of brood layer does not correlate to the presence of virgin queen egg which is crucial for survival of the colony.

Cervical cancer is one of the leading causal cancer-related fatalities in the world. Cervical cancer patients can be treated by conventional treatment such as surgery, radiotherapy, chemotherapy, medications and combination treatments. Currently, more targeted treatments are being developed to cure cervical cancer. The treatments include immunotherapy, virotherapy and gene therapy which will be discussed in this paper. In immunotherapy, the synergy of CTLA-4 suppression and PD-1/PDL-1 immune checkpoint inhibition targeting their corresponding pathways enhanced the human immune system resulting a promising treatment effects. Oncolytic viruses such as Newcastle disease virus selectively infect and kill cancerous cells/tissues without harming normal cells/tissues. This character has made them a potential modality in combating cancer which popularly known as oncolytic virotherapy. Gene therapy delivers modified genetic materials to the target cancer cells via viral and non-viral vectors. It is used to target the abnormal gene, to increase cells’ susceptibility towards drugs or conventional therapy, to induce tumour cells apoptosis, to enhance tumour cell immunogenicity recognition and to inhibit the oncogene expression. The objective of this minireview is to add to the general knowledge on aforementioned therapeutic strategies against cervical cancer.

Current seasonal influenza A virus (IAV) vaccines are strain-specific and require annual reconstitution to accommodate the viral mutations. Mismatches between the vaccines and circulating strains often lead to high morbidity. Hence, development of a universal influenza A vaccine targeting all IAV strains is urgently needed. In the present study, the protective efficacy and immune responses induced by the extracellular domain of Matrix 2 protein (M2e) displayed on the virus-like particles of Macrobrachium rosenbergii nodavirus (NvC-M2ex3) were investigated in BALB/c mice. NvC-M2ex3 was demonstrated to be highly immunogenic even in the absence of adjuvants. Higher anti-M2e antibody titers corresponded well with increased survival, reduced immunopathology, and morbidity of the infected BALB/c mice. The mice immunized with NvC-M2ex3 exhibited lower H1N1 and H3N2 virus replication in the respiratory tract and the vaccine activated the production of different antiviral cytokines when they were challenged with H1N1 and H3N2. Collectively, these results suggest that NvC-M2ex3 could be a potential universal influenza A vaccine.

Virus-like nanoparticles (VLNPs) have been studied extensively as nanocarriers for targeted drug delivery to cancer cells. However, VLNPs have intrinsic drawbacks, in particular, potential antigenicity and immunogenicity, which hamper their clinical applications. Thus, they can be eliminated easily and rapidly by host immune systems, rendering these nanoparticles ineffective for drug delivery. The aim of this study was to reduce the antigenicity of hepatitis B core antigen (HBcAg) VLNPs by shielding them with a hydrophilic polymer, poly(2-ethyl-2-oxazoline) (PEtOx). In the present study, an amine-functionalized PEtOx (PEtOx-NH2) was synthesized using the living cationic ring-opening polymerization (CROP) technique and covalently conjugated to HBcAg VLNPs via carboxyl groups. The PEtOx-conjugated HBcAg (PEtOx-HBcAg) VLNPs were characterized with dynamic light scattering and UV-visible spectroscopy. The colloidal stability study indicated that both HBcAg and PEtOx-HBcAg VLNPs maintained their particle size in Tris-buffered saline (TBS) at human body temperature (37 °C) for at least five days. Enzyme-linked immunosorbent assays (ELISA) demonstrated that the antigenicity of PEtOx-HBcAg VLNPs reduced significantly as compared with unconjugated HBcAg VLNPs. This novel conjugation approach provides a general platform for resolving the antigenicity of VLNPs, enabling them to be developed into a variety of nanovehicles for targeted drug delivery.

Heterotrigona itama is a common stingless bee species found in Southeast Asia. Studies on the health benefts of its honey are limited in comparison with other stingless bee species. Tis study examines the antiobesity benefts found in stingless bee honey (SBH) from H. itama. Te parameters used to measure the benefts were weight change, morphological structures, and biochemical characteristics. Te research was conducted by using rats that were given a high-fat diet (HFD). In total 48 male Sprague Dawley (SD) rats were given a formulated HFD to increase the levels of obesity, the HFD was administered with a value of 0.68 g/cm2. The duration of the treatment was six weeks, and the results show that the induction obesity using the HFD was successful. Following this, the rats were then treated with SBH (at dosages of 1000 mg/kg, 750 mg/kg or 500 mg/kg), with orlistat or with a placebo. Compared with typical obesity treatment methods, the one that used the three dosages of SBH showed a higher reduction in body mass index (BMI), percentage of body weight gain, adiposity index, and relative organ weight (ROW). Te levels of liver enzymes (ALT, AST, and ALP) were also signifcantly lower in SBH-treated groups. Te levels of triglycerides and LDL-cholesterol were signifcantly lower, while the level of HDL-cholesterol was signifcantly higher in comparison with the control obese group. In terms of morphological structures, the number of adipocyte cells was reduced, and the hepatocytes found in the liver were less prone to rupturing when treated with SBH. In conclusion, the administration of SBH led to an improvement in indicators associated with obesity reduction. SBH also possesses a hepatoprotective potential which can reduce the health risks related to obesity.

Stingless bee is a diverse group of highly eusocial bees (meliponines) comprising the Meliponini subfamily of the Apidae family. Throughout the tropics, various kinds of stingless bee have been reared by beekeepers for their products (honey, propolis and bee bread) and pollination services for fruits and vegetables. This meliponiculture in logs or hives is considered safe due to the bee’s inability to sting, with the latter being more preferable for monitoring and managing the colonies and harvesting the products. The source of stingless bee colonies is depending on efficient hunting of feral colonies, which might affect the ecosystem. Following to the growing trend of bee rearing in Malaysia, mainly due to the smart branding strategy of the government through research institutes and universities, e.g. Malaysian Agricultural Research and Development Institute (MARDI), Universiti Malaysia Terengganu and Universiti Sains Malaysia, it is crucial to increase the number of honey-producing hives by colony splitting. The basis of colony splitting includes provision oviposition (POP), swarming and antennation. Colony splitting is necessary due to deforestation, to expand income generation and for entomological study purposes. A more advanced approach in colony splitting is to prepare and rear the virgin queen bee in vitro, resulting in more queens per one single colony. With the advancement in stingless bee rearing techniques, people may apply the colony splitting strategy to maximise stingless bee products and enhance crop production.

Avian polyomavirus (APV) primarily affects young birds and can cause mortality in a wide range of psittacine birds. This is the first study to detect the presence of APV in Malaysia. A total of 85 faecal samples were collected from symptom-free psittacines species from four different breeders in the Klang Valley. Upon genomic DNA extraction, the presence of APV was analysed by PCR using primers APVfull-AF (5'- ACAATGCCTAACGGAACGCC-3') and APVfull-AR (5'-CACCGAAGCGGCGATACTATA-3'). Positive results of 3 kbp PCR amplicon were detected in six out of the 30 samples (20%), which were from yellow-collared macaws, blue-headed parrots, red-crowned macaws, sulphur-crested cockatoos, blue-throated macaws, and Pesquet's parrots. As a conclusion, the prevalence of APV was clearly indicated.

The poultry industry in Malaysia is fast growing but has become under threat due to inclusion bodies hepatitis (IBH) caused by strains of fowl adenovirus (FADV). The present study was carried out to propagate a field isolate of FAdV (UPM T27) and examine its pathogenicity in chicken egg embryo and chicken embryo liver cells. Five Specific Pathogen Free (SPF) chicken eggs were inoculated with 0.1mls of the FAdV UPMT27 isolate via chorioallantoic membrane (CAM) sac route. Supernatant from liver homogenate of dead embryo were used to infect freshly prepared chicken embryo liver (CEL) cells and observed for cytopathic effects for serial passages. Subsequently, passage 1 and 2 isolates were stained with H&E and observed under the microscope. Results show 100% mortality of the eggs at 11 days post inoculation and 100% CPE were observed at 4 dpi respectively. Eosinophilic inclusion bodies were also observed in the hepatocyte after H&E staining. These results confirmed that UPMT27 FAdV isolated from Malaysia are highly pathogenic and can be successfully propagated in CEL cells for future studies of the virus.

Avian polyomavirus disease is among the most common viral diseases of domesticated exotic birds as such in psittacine families. Caused by avian polyomavirus (APV) which possess a circular, double-stranded DNA which encodes for major structural virus protein 1 (VP1) and minor structural proteins VP2, VP3 and VP4, the disease is also known as Budgerigar fledgling disease polyomavirus (BFPyV), Papovavirus, and Psittacine polyomavirus. Infections from APV may lead to cutaneous haemorrhage, abdominal distension, feather abnormalities and even death. The APV virus has a broad avian host range and is known to cause acute chronic disease in several psittacine birds such as parrot, cockatoo, macaw, and budgerigar. The current status of APV epidemiology globally has not been fully recorded. Only the studies of the virus and disease caused within several countries are used as references, and few were done together with detection of beak and feather disease virus. Despite the common occurrence of APV among bird breeders in Malaysia, a very limited study has been done to evaluate the prevalence status of APV in Malaysia. In this review, we wish to disseminate knowledge, particularly to pet owners and bird breeders, on APV characterisations, its updated occurrence worldwide and prevention strategies. This information may be useful to trigger in depth study on the epidemiology of disease and better management practises among breeders.

Since the 10th century B.C., light has been appreciated as a source of energy. Psychologically, a powerful ray of light can induce calmness and excitement in humans. We have been told in the holy books of Islam, Judaism, and Christianity, how the Queen of Sheba (Balqis) had lived with hundreds of windows that allowed beams of sunlight in every morning before she prostrated in front of them. It is probably through this ancient practice that the physician Niels Finsen was inspired to use light to treat diseases and developed the first artificial light source for this purpose back in the 1900s.

The nervous system consists of nerve cells or neurons, which can transmit information in the form of electrical signals to our sense organs. Neurons generally are not a good electrical conductor; however, they have elaborate mechanisms for generating electrical signals by eliminating negative resting potentials.

A perfect blend of design and innovation could serve as catalysts for future change. Designers offer knowledge and competencies to enable innovators envisage new ideas, with the ultimate aim of finding better and long-lasting solutions, by pushing boundaries and changing the norm. Inordinate power of good design will lead to invention of products or services with greater value and encouraging demand.