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Aim: Klebsiella pneumonia has emerged as an increasingly important cause of community-acquired nosocomial infections and many of these strains are highly virulent and exhibit a strong propensity to spread. Infections cause by K. pneumonia produces carbapen¬emase (KPC) enzyme and can be difficult to treat since only a few antibiotics are effective against them. Bacteriophage targeting this strain can be an alternative treatment. Characterisation of bacteriophage is utmost important in assisting the application of bacteriophage in phage therapy. Materials and methods: In the present study, the lytic bacteriophage, k3w7, isolated by the host Klebsiella pneumoniae kP2 was characterised using transmission electron microscope (TEM), plaque assay, and restriction digestive enzyme to investigate mor¬phology, host spectrum, bacteriophage life cycle and stability accordingly. Results and conclusions: As shown by TEM, k3w7 was observed to have the characteristic of icosahedral heads 100 nm and contractile sheaths 120 nm suggesting it belongs to the family of myoviridae.The Investigation has done on the phage growth cycle showed a short latent period of 20 min and a burst size of approximately 220 plaque forming units per infected cell. Stability test showed the phage was stable over a wide range of pH and temperatures. According to restriction analysis, k3w7 had 50 -kb double-stranded DNA genome as well as the heterogeneous nature of genetic material. These findings suggest that K3W7 has a potential use in therapy against infections caused by K. pneumonia produces carbapenemase.

Permasalahan besar yang dihadapi dalam rawatan jangkitan virus herpes manusia jenis I (Human Herpes virus type 1, HHV-1) adalah kehadiran virus mutan yang rintang ubat antivirus iaitu acyclovir. Pencarian ubatan dengan kebolehan mengatasi HHV-1 rintang-acyclovir diperlukan bagi mengatasi masalah ini. Maka, kajian ini bertujuan menentukan konfigurasi Goniothalamin (GTN) yang dipencilkan daripada Goniothalamus umbrosus seterusnya mengenalpasti kebolehannya secara in vitro merencat pencilan HHV-1 mutan yang rintang-acyclovir. Kristal yang terhasil selepas pengekstrakan bahagian akar dan batang G. umbrosus disahkan melalui GC-MS, FTIR dan NMR sebagai GTN. Kiraan puncak gandingan J (J coupling peak calculation) menunjukkan bahawa sebatian aktif ini dalam konfigurasi-cis. Sebelum ujian antivirus dilakukan, nilai kepekatan sitotoksik GTN yang membunuh 50% populasi sel Vero (CC50) ditentukan iaitu 8.747 µg/mL. Kepekatan GTN lebih rendah daripada nilai CC50 digunakan untuk penentuan kesan aktiviti antivirus. Sebanyak sebelas pencilan mutan digunakan bagi menentukan kesan aktiviti antivirus GTN dalam asai pasca-rawatan. Nilai kepekatan berkesan menurunkan 50% pembentukan plak (EC50) adalah antara 0.47 µg/mL (2.35 µM) hingga 1.42 µg/mL (6.42 µM). Nilai indeks pemilihan (SI) iaitu nisbah keberkesanan aktiviti antivirus berbanding kesitotoksikan adalah antara 6 hingga 17 yang menunjukkan bahawa GTN mempunyai potensi baik untuk bertindak sebagai agen antivirus. Kesimpulannya, GTN dalam konfigurasi cis berkesan merencat pencilan virus mutan rintang-acyclovir. Potensi tindakan tersebut penting dalam menangani kehadiran virus rintang-acyclovir terutama yang mempunyai mutasi pada timidin kinase atau polimerase DNA.

Prodigiosin, a red linear tripyrrole pigment found in Serratia marcescens, is one such naturally occurring compound that has gained wide attention owing to its numerous biological activities, including antibacterial, antifungal, antimalarial, anticancer, and immunosuppressive properties. This study was conducted to evaluate the possible antiviral activity of prodigiosin against Enterovirus 71, a causative agent of hand, foot, and mouth disease (HFMD). Preliminary studies were done in silico by analyzing the interaction of prodigiosin with amino acid residues of five EV71-target proteins. Interaction refinement analysis with FireDock revealed that 2C helicase (-48.01 kcal/moL) has the most negative global energy, followed by capsid (-36.52 kcal/moL), 3C protease (-34.16 kcal/moL), 3D RNA polymerase (-30.93 kcal/moL) and 2A protease (-20.61 kcal/moL). These values are indicative of the interaction strength. Prodigiosin was shown to form chemical bonds with specific amino acid residues in capsid (Gln-30, Asn-223), 2A protease (Trp-33, Trp-142), 2C helicase (Tyr-150, His-151, Gln-169, Ser-212), 3C protease (Glu-50), and 3D RNA polymerase (Ala-239, Tyr-237). To investigate further, prodigiosin was extracted from S. marcescens using a methanolic extraction method. In vitro studies revealed that prodigiosin, with an IC50 value of 0.5112 μg/mL, reduced virus titers by 0.17 log (32.39%) in 30 min and 0.19 log (35.43%) in 60 min. The findings suggest that prodigiosin has antiviral activity with an intermediate inhibitory effect against EV71. As a result of this research, new biological activities of prodigiosin have been identified.

The antiviral activity of goniothalamin (GTN) from Goniothalamus umbrosus root, virgin coconut oil (VCO) and aloe vera extract (AVE) have been reported, but the combined activity is yet to be determined. This study aims to determine the stability, cytotoxicity and effectiveness of pure GTN, combination of GTN and VCO (GTN+VCO) or combination of GTN and AVE (GTN+ AVE) towards in vitro Human Herpesvirus 1 (HHV-1) infection. GTN stability improved significantly (α

The rapid spread of the SARS-CoV-2 in the COVID-19 pandemic had raised questions on the route of transmission of this disease. Initial understanding was that transmission originated from respiratory droplets from an infected host to a susceptible host. However, indirect contact transmission of viable virus by fomites and through aerosols has also been suggested. Herein, we report the involvement of fine indoor air particulates with a diameter of ≤ 2.5 µm (PM2.5) as the virus’s transport agent. PM2.5 was collected over four weeks during 48-h measurement intervals in four separate hospital wards containing different infected clusters in a teaching hospital in Kuala Lumpur, Malaysia. Our results indicated the highest SARS-CoV-2 RNA on PM2.5 in the ward with number of occupants. We suggest a link between the virus-laden PM2.5 and the ward’s design. Patients’ symptoms and numbers influence the number of airborne SARS-CoV-2 RNA with PM2.5 in an enclosed environment.

Goniothalamin (GTN) has been proven to cause cell cycle arrest and apoptosis in human herpesvirus 1 (HHV-1) infected cells, but interestingly our preliminary transcriptomic analysis revealed other possible modes of action. The data showed that GTN treatment of HHV-1 clinical strain infected cells induced expression of the KLHL24 gene that encodes the Kelch-like 24 protein (KLHL24), a transcriptional inhibitor of HHV-1 immediate-early and early genes. An miRNA, hsv1-miR-H27, produced by HHV-1 has also been discovered to control the expression of KLHL24. In order to understand the cause of KLHL24 up-regulation, a time point study was conducted to investigate the effect of GTN on KLHL24 and hsv1-miR-H27 expression. Through RT-qPCR analysis, we found that HHV-1 down-regulated KLHL24 significantly (p < 0.05) starting from 12 hpi, while a significant up-regulation (p < 0.05) was observed upon GTN treatment of the infected cells at 4 and 8 hpi. For protein level analysis, significant down-regulation of KLHL24 (p < 0.05) was observed at all time points in HHV-1 infected cells. Intriguingly, treatment with GTN on HHV-1 infected cells showed no significant changes in protein expression compared to cells without any treatment. In addition, the miRNA hsv1-miR-H27 was detected from 16 hpi and treatment with GTN on infected cells showed down-regulation of the miRNA. This was in congruity with the recovery of KLHL24 down-regulation in GTN treated HHV-1 infected cells, confirming that GTN caused down-regulation of hsv1-miR-H27 that governs the expression of KLHL24. This study provides insights that GTN could be a potential multifaceted antiviral.ImportanceThis study provides evidence that GTN possesses a distinct mode of antivirus against HHV-1 compared to currently available antivirals. Our findings showed that GTN caused the down-regulation of a viral miRNA, which inhibits the expression of a cellular protein known as KLHL24. This protein serves as a transcriptional inhibitor of HHV-1 immediate-early and early genes. The down-regulation of this miRNA lead to the up-regulation of KLHL24 and eventually halted HHV-1 replication. With the previously reported antiviral mechanism and the outcome of this study, GTN is a potential multifaceted anti-HHV-1 agent.

Edible bird’s nest (BN) is a Chinese traditional medicine with innumerable health benefits, including anti-viral, anti-inflammatory, neuroprotective, and immunomodulatory effects. A small number of studies have reported the anti-viral effects of EBN against influenza infections using in vitro and in vivo models, highlighting the importance of sialic acid and thymol derivatives in their therapeutic effects. At present, studies have reported that EBN suppresses the replicated virus from exiting the host cells, reduces the viral replication, endosomal trafficking of the virus, intracellular viral autophagy process, secretion of pro-inflammatory cytokines, reorient the actin cytoskeleton of the infected cells, and increase the lysosomal degradation of viral materials. In other models of disease, EBN attenuates oxidative stress-induced cellular apoptosis, enhances proliferation and activation of B-cells and their antibody secretion. Given the sum of its therapeutic actions, EBN appears to be a candidate that is worth further exploring for its protective effects against diseases transmitted through air droplets. At present, anti-viral drugs are employed as the first-line defense against respiratory viral infections, unless vaccines are available for the specific pathogens. In patients with severe symptoms due to exacerbated cytokine secretion, anti-inflammatory agents are applied. Treatment efficacy varies across the patients, and in times of a pandemic like COVID-19, many of the drugs are still at the experimental stage. In this review, we present a comprehensive overview of anti-viral and anti-inflammatory effects of EBN, chemical constituents from various EBN preparation techniques, and drugs currently used to treat influenza and novel coronavirus infections. We also aim to review the pathogenesis of influenza A and coronavirus, and the potential of EBN in their clinical application. We also describe the current literature in human consumption of EBN, known allergenic or contaminant presence, and the focus of future direction on how these can be addressed to further improve EBN for potential clinical application.

The COVID-19 pandemic has plunged the world into uncharted territory, leaving people feeling helpless in the face of an invisible threat of unknown duration that could adversely impact the national economic growths. According to the World Health Organization (WHO), the SARS-CoV-2 spreads primarily through droplets of saliva or discharge from the mouth or nose when an infected person coughs or sneezes. However, the transmission of the SARS-CoV-2 through aerosols remains unclear. In this study, computational fluid dynamic (CFD) is used to complement the investigation of the SARS-CoV-2 transmission through aerosol. The Lagrangian particle tracking method was used to analyze the dispersion of the exhaled particles from a SARS-CoV-2-positive patient under different exhale activities and different flow rates of chilled (cooling) air supply. Air sampling of the SARS-CoV-2 patient ward was conducted for 48-h measurement intervals to collect the indoor air sample for particulate with diameter less than 2.5 μm. Then, the reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) was conducted to analyze the collected air sample. The simulation demonstrated that the aerosol transmission of the SARS-CoV-2 virus in an enclosed room (such as a hospital ward) is highly possible.

A study was conducted to investigate the antiviral activity of aqueous extracts from Orthosiphon stamineus (OS). Extraction was done using different parts of OS. The whole plant except root (WPOS), leaves (LOS) and flowers (FOS) of OS were extracted using aqueous extraction method. Cytotoxicity was assessed using 3-(4,5-dimethylthiazol-2,5-diphenyl tetrazolium bromide (MTT) assay. Plaque reduction assays were carried out to evaluate the antiviral activity of OS extract against herpes simplex virus type 1 (HSV-1). These include post-treatment, pre-treatment and virucidal assays. High antiviral activity was observed in post-treatment and virucidal assay with 100% reduction of HSV-1 plaque at 0.39 mg/mL in LOS, FOS and WPOS. In pre-treatment assay, 79%, 84% and 97% plaque reduction using the same concentration was observed in FOS, LOS and WPOS, respectively. In conclusion, this study showed that OS aqueous extract has promising potential to be explored as anti-HSV-1 agent regardless of the mode of treatment.

The present study was aimed at determining the compounds available in Eleusine indica methanol extract and the effects on herpes simplex virus type 1 (HHV1) replication cycle and progeny infectivity. Twelve compounds mostly from the flavonoid and phenolic groups were identified by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) analysis. The effect on replication phases of HHV1 was determined by time-of-addition, time-removal and virus yield reduction assays with expression of selected genes analysed by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The extract inhibited plaque formation the most during the first 2 h and at 24 h of infection. Plaque formation inhibition was also noted at all other time points but at lesser percentage. Treatment with E. indica reduced progeny infectivity when treated for 10 h and was dose-dependent. E. indica methanol extract inhibited immediate early, early and late phases of HHV1 replication cycle by modifying the expression of UL54, UL27 and UL30 genes during the infection. Immunostaining of infected cells confirmed that E. indica inhibited mainly Glycoproteins B but not Glycoprotein C and D. Thus, the methanol extract of E. indica has the ability to alter HHV1 replication cycle at almost all stages and reduce progeny infectivity.

Alcohol use disorder (AUD) is characterized by compulsive binge alcohol intake, leading to various health and social harms. Protein Kinase C epsilon (PKCe), a specific family of PKC isoenzyme, regulates binge alcohol intake and potentiates alcohol-related cues. Alcohol via upstream kinases like mammalian target to rapamycin complex 1 (mTORC1) or 2 (mTORC2), may affect the activities of PKCe or vice versa in AUD. mTORC2 phosphorylates PKCe at hydrophobic and turn motif, and mTORC2 was recently reported to be associated with alcohol seeking behavior, suggesting the potential role of mTORC2-PKCe interactions in pathophysiology of AUD. Mammalian target to rapamycin complex 1 (mTORC1), another form of mTOR complex regulates translation of synaptic proteins involved in alcohol-induced plasticity. Hence, in this article, we aimed to review the molecular composition of mTORC1 and mTORC2, drugs targeting PKCe, mTORC1, and mTORC2 in AUD, upstream regulation of mTORC1 and mTORC2 in AUD and downstream cellular mechanisms of mTORCs in pathogenesis of AUD.

A styrylpyrone derivative (SPD) known as goniothalamin is a compound isolated from Goniothalamus umbrosus. Herein, we showed SPD inhibition of human herpes virus type-1 (HHV-1) infection. In addition, the possible mechanism of anti-HHV-1 activity was proposed through a combination treatment between SPD and commercial antiherpetic drug, Foscarnet (PFA).

Endophytes are organisms, often fungi and bacteria that live in living plant cells. These organisms reside in the living tissues of the host plant in a variety of relationships, ranging from symbiotic to slightly pathogenic. The endophytes may produce a plethora of substances that have potential to be used in modern medicine, agriculture and industry. The aims of this study are to isolate, identify and screening antimicrobial activity of bacterial endophytes. The endophytes were isolated using nutrient agar, incubated at 37°C for 48 hours. Identification of the isolates were done based on morphological characteristics, biochemical tests and 16S rDNA molecular analysis. Disk diffusion method was used to screen for antimicrobial activity of metabolites from endophytes against pathogenic bacteria. Screening for antifungal activity of selected endophytes was done using dual culture method againts pathogenic fungi followed by Kirby-Bauer method. Results showed endophytes designated as B2c and B7b have positive antimicrobial activity. The metabolites from isolate B2c showed antimicrobial activity against pathogenic bacteria methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus and Staphylococcus epidermis, while isolate B7b have positive activities againts MRSA, S. aureus and Pseudomonas aeruginosa. Isolates B2c displayed antifungal activity against Fusarium oxysporum, Fusarium solani, Phytophthora palmivora and Colletotrichum gloeosporioides. Identification using biochemical tests and 16S rDNA sequences identified isolate B2c as Pseudomonas resinovorans with 97% homology and isolate B7b as Bacillus subtilis with 98% homology.

Orthosiphon stamineus Benth (Lamiaceae) is a plant with ethnobotanical applications including antifungal and antibacterial properties. This study aimed to evaluate the phytochemical contents of Orthosiphon stamineus leaves water extract prepared in cold and hot distilled water. Phytochemical screening revealed the presence of phytochemicals components such as a flavonoid, terpenoid and steroid in both extracts. Cold water extract has two extra components: saponin and alkaloid that may be destroyed by the exposure to heat.

Melastoma malabathricum is a traditional herb that is used to treat wound on skin. It has also been proven to have antiviral activity against Herpes Simplex virus type 1 (HSV-1). In this study, M. malabathricum cream formulation was developed by incorporating M. malabathricum aqueous extract into cream base. The safety and biocompatibility of the formulated cream was investigated by topically applying the cream onto the back of ICR mice skin. Treatment with M. malabathricum was found to accelerate wound contraction with less scar formation. The effect of M. malabathricum has prompted a possibility that M. malabathricum might contribute in enhancing the healing process of cutaneous lesion caused by HSV-1. The formulated cream did not cause any skin irritation or adverse effect to ICR mice when topically applied within seven days of exposure.

The increasing number of death due to cancer emphasizes the need of novel anticancer agents. Styrylpyrone derivative (SPD) was previously found to have potential anticancer action towards many types of cancer. Some of the SPD-anticancer mechanisms were elucidated as induction of cancer cell apoptosis. However, more understanding on cancer cell type specific action of SPD-anticancer effects needs to be evaluated. HCT-116 cell line, a type of human colon carcinoma, was used to study SPD-anticancer effect. It was found that SPD concentration as low as 0.25 µM was able to inhibit 80% growth of cancer cells. IC50 value of SPD for HCT-116 was found to be 0.038 µM. Neurotoxicity test, carried out to determine the adverse effect of SPD towards nerve cells, gives CC50 value as 4.88 µM, thus concluded it to be a neurotoxic compound.

Styrylpyrone derivative (SPD) from Goniothalamus umbrosus has been shown to have antiviral properties against Herpes Simplex virus type-1 (HSV-1). This study aimed to evaluate the purity of isolated SPD and stability of SPD-incorporated formulations. Pure SPD was isolated from dried roots of G. umbrosus as confirmed by GC-MS. Two types of SPD-incorporated products (ointment and gel) were produced. Both products showed stable physical properties after two months and retained the SPD content for one month.

Orthosiphon stamineus Benth (Lamiaceae) is a plant with many ethnobotanical uses including antifungal and antibacterial activities. This study is aimed to determine the cytotoxicity and phytochemical content of O. stamineus leaves and flower using ethanol and water as solvents. The cytotoxicity of the extracts towards Vero cell was determined by MTT assay. The CC50 values were between 3.4-7.4 mg/ml and can be considered as nontoxic. Phytochemical screening revealed terpenes, alkaloid and phenolic were present in the leaves and flower of O. stamineus that might pose as the bioactive compound.

In this study, styrylpyrone derivative (SPD) extracted from Goniothalamus umbrosus root was tested against herpes simplex virus (HSV) strain KOS-1. Firstly, the cytotoxicity of SPD on Vero cells was tested and the value of cytotoxic concentration, CC50, was 44 μM (8.88 μg/mL), and the 50% Effective Concentration, EC50, was 3.35 μM (0.67 μg/mL). Selectivity index of SPD against HSV Kos-1 was more than 13 indicating potential as antiviral agent. Three treatments were used in the antiviral test; 1) post-treatment, 2) pre-treatment, and 3) virucidal. The results revealed that the post-treatment was more effective in inhibiting viral replication compared to pre-treatment. The findings indicated that the SPD from G. umbrosus has good potential for prospective nature-based antiviral drug.

Eleven strains of acyclovir (ACV)-resistant herpes simplex virus type 1 (HSV-1) were generated from HSV-1 clinical isolates by exposure to ACV. Genotype of the thymidine kinase (TK) and DNA polymerase (pol) genes from these mutants were further analyzed. Genotypic analysis revealed four non-synonymous mutations in TK gene associated with gene polymorphism and two to three non-synonymous mutations in DNA pol gene. Seven and six strains contained at least one resistance-associated mutation at TK and DNA pol gene, respectively. Resistance-associated mutations within the TK gene consisted of 64% of non-synonymous frameshift mutations within the homopolymer region of G’s and C’s, and 36% of non-synonymous nucleotide substitutions of the conserved gene region (C336Y, R51W and R222H), nucleotide that produced stop codon (L288Stop) and two amino acid substitutions outside the conserved region (E39G & L208F). There were 10 non-synonymous amino acid substitutions located outside the conserved region with the unclear significance to confer resistance observed. Resistance-associated mutations in DNA pol gene include insertion of G at the homopolymer region of G’s (794–797) and amino acid substitutions inside (V621S) or outside (H1228D) the conserved region. In silico analysis of the mutated TK (C336Y, R51W and L208F), and DNA pol (V621S and H1228D) suggested structural changes that might alter the stability of these proteins. However, there were several mutations with unclear significance to confer ACV-resistance identified, especially mutations outside the conserved region.

Acyclovir (ACV) is an antiviral drug of choice in healthcare setting to treat infections caused by herpes viruses, including, but not limited to genital herpes, cold sores, shingles and chicken pox. Acyclovir resistance has emerged significantly due to extensive use and misuse of this antiviral in human, especially in immunocompromised patients. However, it remains unclear about the amino acid substitutions in thymidine (TK) gene, which specifically confer the resistance-associated mutation in herpes simplex virus. Hence, acyclovir-resistant HSV-1 was selected at high concentration (2.0 - 4.5 μg/mL), and the TK-gene was subjected to sequencing and genotypic characterization. Genotypic sequences comparison was done using HSV-1 17 (GenBank Accesion no. X14112) for resistance-associated mutation determination whereas HSV-1 KOS, HSV-1 473/08 and HSV clinical isolates sequences were used for polymorphism-associated mutation. The result showed that amino acid substitutions at the non-conserved region (UKM-1: Gln34Lys, UKM-2: Arg32Ser & UKM-5: Arg32Cys) and ATP-binding site (UKM-3: Tyr53End & UKM-4: Ile54Leu) of the TK-gene. These discoveries play an important role to extend another dimension to the evolution of acyclovir-resistant HSV-1 and suggest that selection at high ACV concentration induced ACV-resistant HSV-1 evolution. These findings also expand the knowledge on the type of mutations among acyclovir-resistant HSV-1. In conclusion, HSV-1 showed multiple strategies to exhibit acyclovir resistance, including amino acid substitutions in the TK gene.