Inactivation of human norovirus by chlorous acid water, a novel chlorine-based disinfectant.

Introduction: Human norovirus (HuNoV) is a leading cause of infectious gastroenteritis. Since HuNoV shows resistance to alcohol, chlorine-based sanitizers are applied to decontaminate the virus on environmental surfaces. Chlorous acid water (CA) has been recently approved as a novel chlorine-based disinfectant categorized as a Type 2 OTC medicine in Japan.

Aromatic interaction of hydantoin compounds leads to virucidal activities.

Virus inactivation or disinfection is the first line of protection against virus infection. Here, we report for the first time the virus inactivation (virucidal) activities of hydantoin and its derivative, 1-methylhydantoin against enveloped herpes simplex virus type-1. These hydantoin compounds showed favorable interaction with aromatic amino acids, similarly to arginine hydrochloride also exhibiting aromatic interaction and virucidal activities on the same virus.

The Human Gut Microbe Suppresses Toxin Release from by Inhibiting Autolysis.

Disruption of the human gut microbiota by antibiotics can lead to (CD)-associated diarrhea. CD overgrowth and elevated CD toxins result in gut inflammation. Herein, we report that a gut symbiont, (BT), suppressed CD toxin production.

Effect of thymoquinone on Fusobacterium nucleatum‑associated biofilm and inflammation.

Periodontitis affects oral tissues and induces systemic inflammation, which increases the risk of cardiovascular disease and metabolic syndrome. Subgingival plaque accumulation is a trigger of periodontitis. Fusobacterium nucleatum (FN) contributes to subgingival biofilm complexity by intercalating with early and late bacterial colonizers on tooth surfaces.

Characterization of Virucidal Activities of Chlorous Acid.

Virucidal effects of chlorous acid on enveloped and non-enveloped viruses were characterized. The virucidal activity was prominent in enveloped viruses. However, among non-enveloped viruses, viruses such as human rhinovirus and feline calicivirus showed a significant sensitivity to the reagent, whereas others such as poliovirus and coxsackievirus showed a weak sensitivity to the reagent, suggesting the presence of 2 classes of sensitivity to the reagent, among non-enveloped viruses.

L‑histidine augments the oxidative damage against Gram‑negative bacteria by hydrogen peroxide.

Excessive damage to DNA and lipid membranes by reactive oxygen species reduces the viability of bacteria. In the present study, the proliferation of recA‑deficient Escherichia coli strains was revealed to be inhibited by 1% L‑histidine under aerobic conditions. This inhibition of proliferation was not observed under anaerobic conditions, indicating that L‑histidine enhances oxidative DNA damage to E.

Microbicidal effects of weakly acidified chlorous acid water against feline calicivirus and Clostridium difficile spores under protein-rich conditions.

Sanitation of environmental surfaces with chlorine based-disinfectants is a principal measure to control outbreaks of norovirus or Clostridium difficile. The microbicidal activity of chlorine-based disinfectants depends on the free available chlorine (FAC), but their oxidative potential is rapidly eliminated by organic matter. In this study, the microbicidal activities of weakly acidified chlorous acid water (WACAW) and sodium hypochlorite solution (NaClO) against feline calcivirus (FCV) and C.

Antimicrobial activity and stability of weakly acidified chlorous acid water.

The antimicrobial activity of weakly acidified chlorous acid water (WACAW) against Staphylococcus aureus, non-pathogenic Escherichia coli, enterohemorrhagic E. coli (EHEC O157:H7), Candida albicans, and spore-forming Bacillus and Paenibacillus species was evaluated in vitro. The antiviral activity was also examined using feline calicivirus (FCV).

Different interaction between HIV-1 Vif and its cellular target proteins APOBEC3G/APOBEC3F.

We examined a series of site-directed point mutants of human immunodeficiency virus type 1 (HIV-1) Vif for their interaction with cellular anti-viral factors APOBEC3G/APOBEC3F. Mutant viruses that display growth-defect in H9 cells did not counteract effectively APOBEC3G and/or APOBEC3F without exception, as monitored by single-cycle infectivity assays. While growth-defective mutants of Vif C-terminal region were unable to suppress APOBEC3G/APOBEC3F, some N-terminal region mutants did neutralize one of APOBEC3G/APOBEC3F.

Amino acid alterations in Gag that confer the ability to grow in simian cells on HIV-1 are located at a narrow CA region.

We previously generated a prototype monkey-tropic human immunodeficiency virus type 1 (HIV-1) designated NL-DT5R. This viral clone has a small region of simian immunodeficiency virus (SIV) within Gag capsid (CA) protein and also SIV Vif protein, but displays a poor growth phenotype in simian cells. To improve the growth potential of NL-DT5R, we have constructed a series of its gag variant viruses.

Determination of HIV-1 infectivity by lymphocytic cell lines with integrated luciferase gene.

We have established lymphocytic cell lines H9 and M8166 that contain integrated copy of luciferase gene under the control of human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR). While H9 is known to be non-permissive for or insensitive to some particular mutant strains of HIV/simian immunodeficiency virus (SIV), M8166 is one of the most susceptible lines to various HIV/SIVs. The luciferase gene driven by HIV-1 LTR was transfected into H9 and M8166 cells with the neo gene, and cell lines were selected by G418.