Electrolyzed Saline Targets Biofilm Periodontal Pathogens In Vitro

Preventing the development and recurrence of periodontal diseases often includes antimicrobial mouthrinses to control the growth of the periodontal pathogens. Most antimicrobials are nonselective, targeting the symbiotic oral species as well as the dysbiosis-inducing ones. This affects the overall microbial composition and metabolic activity and consequently the host-microbe interactions, which can be detrimental (associated with inflammation) or beneficial (health-associated). Consequently, guiding the antimicrobial effect for modulating the microbial composition to a health-associated one should be considered. For such an approach, this study investigated electrolyzed saline as a novel rinse. Electrolyzed saline was prepared from sterile saline using a portable electrolysis device. Multispecies oral homeostatic and dysbiotic biofilms were grown on hydroxyapatite discs and rinsed daily with electrolyzed saline (EOS). Corresponding positive (NaOCl) and negative (phosphate-buffered saline) controls were included. After 3 rinses, biofilms were analyzed with viability quantitative polymerase chain reaction and scanning electron microscopy. Supernatants of rinsed biofilms were used for metabolic activity analysis (high-performance liquid chromatography) through measuring organic acid content. In addition, human oral keratinocytes (HOKs) were exposed to EOS to test biocompatibility (cytotoxicity and inflammation induction) and also to rinsed biofilms to assess their immunogenicity after rinsing. Rinsing the dysbiotic biofilms with EOS could reduce the counts of the pathobionts (>3 log10 Geq/mm2 reduction) and avert biofilm dysbiosis (≤1% pathobiont abundance), leading to the dominance of commensal species (≥99%), which altered both biofilm metabolism and interleukin 8 (IL-8) induction in HOKs. EOS had no harmful effects on homeostatic biofilms. The scanning electron micrographs confirmed the same. In addition, tested concentrations of EOS did not have any cytotoxic effects and did not induce IL-8 production in HOKs. EOS showed promising results for diverting dysbiosis in in vitro rinsed biofilms and controlling key periopathogens, with no toxic effects on commensal species or human cells. This novel rinsing should be considered for clinical applications.

Long-term study on wastewater SARS-CoV-2 surveillance across United Arab Emirates

Wastewater-based epidemiology (WBE) demonstrates an efficient tool to monitor and predict SARS-CoV-2 community distribution. Many countries across the world have adopted the technique, however, most of these studies were conducted for a short duration with a limited sampling size. In this study, long-term reliability and quantification of wastewater SARS-CoV-2 surveillance is reported via analyzing 16,858 samples collected from 453 different locations across the United Arab Emirates (UAE) from May 2020 to June 2022. The collected composite samples were first incubated at 60 °C followed by filtration, concentration, and then RNA extraction using commercially available kits. The extracted RNA was then analyzed by one-step RT-qPCR and RT-ddPCR, and the data was compared to the reported clinical cases. The average positivity rate in the wastewater samples was found to be 60.61 % (8.41-96.77 %), however, the positivity rate obtained from the RT-ddPCR was significantly higher than the RT-qPCR suggesting higher sensitivity of RT-ddPCR. Time-lagged correlation analysis indicated an increase in positive cases in the wastewater samples when the clinical positive cases declined suggesting that wastewater data are highly affected by the unreported asymptomatic, pre-symptomatic and recovering individuals. The weekly SARS-CoV-2 viral count in the wastewater samples are positively correlated with the diagnosed new clinical cases throughout the studied period and the studied locations. Viral count in wastewater peaked approximately one to two weeks prior to the peaks appearing in active clinical cases indicating that wastewater viral concentrations are effective in predicting clinical cases. Overall, this study further confirms the long-term sensitivity and robust approach of WBE to detect trends in SARS-CoV-2 spread and helps contribute to pandemic management.

Oral Biofilm Cryotherapy as a Novel Ecological Modulation Approach

Oral cryotherapy is used in dentistry as a safe, simple, and low-cost treatment for a variety of oral lesions. It is well known for its ability to aid in the healing process. However, its effect on oral biofilms is unknown. As a result, the purpose of this study was to assess the effects of cryotherapy on in vitro oral biofilms. In vitro multispecies oral biofilms were grown on the surface of hydroxyapatite discs in symbiotic or dysbiotic states. CryoPen X+ was used to treat the biofilms, whereas untreated biofilms served as control. One set of biofilms was collected for study immediately after cryotherapy, whereas another group was reincubated for 24 h to permit biofilm recovery. Changes in biofilm structure were analyzed with a confocal laser scanning microscope (CLSM) and a scanning electron microscope (SEM), while biofilm ecology and community compositional changes were analyzed with viability DNA extraction and quantitative polymerase chain reaction (v-qPCR) analysis. One cryo-cycle immediately reduced biofilm load by 0.2 to 0.4 log₁₀ Geq/mL, which increased with additional treatment cycles. Although the bacterial load of the treated biofilms recovered to the same level as the control biofilms within 24 h, the CLSM detected structural alterations. Compositional alterations were also detected by SEM, corroborating the v-qPCR findings that showed ≈≤10% incidence of pathogenic species compared to nontreated biofilms that encompassed ≈45% and 13% pathogenic species in dysbiotic and symbiotic biofilms, respectively. Spray cryotherapy showed promising results in a novel conceptual approach to the control of oral biofilms. Acting selectively by targeting oral pathobionts and retaining commensals, spray cryotherapy could modify the ecology of in vitro oral biofilms to become more symbiotic and prevent the evolution of dysbiosis without the use of antiseptics/antimicrobials.

Compromised BRCA1-PALB2 interaction is associated with breast cancer risk

The major breast cancer suppressor proteins BRCA1 and BRCA2 play essential roles in homologous recombination (HR)-mediated DNA repair, which is thought to be critical for tumor suppression. The two BRCA proteins are linked by a third tumor suppressor, PALB2, in the HR pathway. While truncating mutations in these genes are generally pathogenic, interpretations of missense variants remains a challenge. To date, patient-derived missense variants that disrupt PALB2 binding have been identified in BRCA1 and BRCA2; however, there has not been sufficient evidence to prove their pathogenicity in humans, and no variants in PALB2 that disrupt either its BRCA1 or BRCA2 binding have been reported. Here, we report on the identification of a novel PALB2 variant, c.104T>C [p.L35P], that segregated in a family with a strong history of breast cancer. Functional analyses showed that L35P abrogates the PALB2-BRCA1 interaction and completely disables its abilities to promote HR and confer resistance to platinum salts and PARP inhibitors. Whole-exome sequencing of a breast cancer from a c.104T>C carrier revealed a second, somatic, truncating mutation affecting PALB2, and the tumor displays hallmark genomic features of tumors with BRCA mutations and HR defects, cementing the pathogenicity of L35P. Parallel analyses of other germline variants in the PALB2 N-terminal BRCA1-binding domain identified multiple variants that affect HR function to varying degrees, suggesting their possible contribution to cancer development. Our findings establish L35P as the first pathogenic missense mutation in PALB2 and directly demonstrate the requirement of the PALB2-BRCA1 interaction for breast cancer suppression.

Therapeutic outcome of 6198 interferon-naïve Egyptian patients with chronic hepatitis C: a real-life experience and lessons to be learned in DAAs' era

Antiviral therapy for HCV infection has been validated in randomized controlled clinical trials, but its value in the real world is less well studied. There is relatively little data on real-world responses to interferon-based therapies for patients with genotype 4 infection. We aimed to examine experience with large-scale access to antiviral therapy in chronic HCV in a real-life clinical setting in Egypt. Detailed pretreatment data of 6198 IFN-naïve chronic HCV patients who had received PEG-IFN/RBV therapy at Cairo-Fatemic Hospital, Egypt, between 2009 and 2012 were obtained from the HCV database. At week 12, 95.7% of patients had undetectable HCV RNA, and by week 24 and 48, breakthrough was 6% and 4%, respectively. However, 43.7% of patients discontinued treatment prematurely, and intent to treat end of treatment response was 44.6% (79.3% per protocol). Sustai-ned response data were available from only 1281 patients and was 84.9%. Haematological abnormalities were comparable in patients who did or did not comply with therapy. This is the first real-world, large-scale experience of antiviral therapy in chronic HCV in Egypt. Suboptimal response in HCV predominantly genotype 4 was mainly driven by noncompliance as well as gaps in the healthcare system leading to treatment discontinuation. These results need to be considered in the era of all oral antiviral regimes.

Defective bone repair in mast cell deficient mice with c-Kit loss of function

KitW-sh mice carry an inactivating mutation in the gene encoding the receptor for stem cell factor, which is expressed at high levels on the surface of haematopoietic precursor cells. The mutation results in mast cell deficiency, a variety of defects in innate immunity and poorly defined abnormalities in bone. The present study was designed to characterise healing of a cortical window defect in skeletally mature KitW-sh mice using high-resolution micro computed tomographic imaging and histological analyses. The cortical bone defect healed completely in all wild type mice but failed to heal in about half of the KitW-sh mice by 12 weeks post-operative. Defective healing was associated with premature and excessive expression of TRAP positive cells embedded in fibrous marrow but with little change in ALP activity. Immuno-histochemical analyses revealed reduced CD34 positive vascular endothelial cells and F4/80 positive macrophages at 1 and 2 weeks post-operative. Impaired bone healing in the KitW-sh mice was therefore attributed to altered catabolic activity, impaired re-vascularisation and compromised replacement of woven with compact bone.

Antioxidant and schistosomicidal effect of Allium sativum and Allium cepa against Schistosoma mansoni different stages

OBJECTIVE

The schistosomicidal properties of garlic (Allium sativum) and onion (Allium cepa) powder were tested in vitro against Schistosoma mansoni miracidia, schistosomula, cercaria and adult worms. Results indicate their strong biocidal effects against all stages of the parasite and also show scavenging inhibitory effect on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide (NO).

MATERIALS AND METHODS

In the present work, the in vivo effects of A. sativum and A. cepa on lipid peroxide and some antioxidant enzymes; thioredoxin reductase (TrxR), sorbitol dehydrogenase (SDH), superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) (as they have a crucial role in host protection against invading parasite) were also studied.

RESULTS

The data demonstrate that, there was a significant inhibition in SOD, CAT, GR, TrxR and SDH in infected liver while, significant elevation was detected in lipid peroxide as compared to the normal control. The current resultS clearly revealed that, the used both edible plants enhance the host antioxidant system indicated by lowering in lipid peroxide and stimulation of SOD, CAT, GR, TrxR and SDH enzyme levels.

CONCLUSIONS

Enhancement of such enzymes using A. sativum and A. cepa could in turn render the parasite vulnerable to damage by the host and may play a role in the antischistosomal potency of the used food ingredients.

Sublethal concentration of Ambrosia maritima(Damsissa) affecting compatibility of Biomphalaria alexandrina snails to infection with Schistosoma mansoni through disturbing the glycolytic pathway

High glycolytic flux as an emergency pathway for generating ATP was recorded as the most important metabolic pathway required for the success of Biomphalaria-Schistosome sporocyst interaction. Effect of LC25 of dry powdered Ambrosia maritima (Damsissa) as plant molluscicide on hexokinase (HK), pyruvate kinase(PK), glucose phosphate isomerase(GPI) was tested. It resulted in a significant inhibition of the three investigated enzymes. Treatment of snails with LC10 concentrations of A. maritima reduced considerably the infection rate of Biomphalaria alexandrina with Schistosoma mansoni to be 34% compared to an infection rate of 80% in control non-treated snails. Longer prepatent period and remarkable decrease in cercarial production was also recorded in snails treated with the sublethal concentrations of this molluscicide.

High performance liquid chromatographic separation of cisplatin and its hydrolysis products on alumina and application to studies of their interaction with cysteine

An alumina stationary phase has been assessed in the study of the retention behaviour of the anticancer drug cisplatin and its major hydrolysis products. Parameters such as buffer concentration in the mobile phase, pH, organic modifier and competing ion have been investigated in order to optimize chromatographic separation with ultraviolet detection. The separation scheme developed has been used to monitor the hydrolysis of cisplatin in aqueous and saline media, and to monitor the interaction of hydrolysed solutions of cisplatin with the amino acid cysteine. A new peak was observed in the chromatograms of such mixtures when they had been allowed to stand for periods of greater than 16 h and, from analysis of the data obtained, it was concluded that this new peak was due to a complex formed between the mono-aquo hydrolysis product of cisplatin and the amino acid.