Development of Therapeutic and Prophylactic Zinc Compositions for Use against COVID-19: A Glimpse of the Trends,Inventions, and Patents

Zinc is an essential nutrient for human health; it is involved in the catalytic, structural, and regulatory functions of the human cellular system. Different compositions of zinc, as well as its pharmaceutically acceptable salts, are available on the market. Recent studies have demonstrated the role of zinc in combating COVID-19. It has been determined that zinc prevents the entry of SARS-CoV-2 into cells by lowering the expression of ACE-2 receptors and inhibiting the RNA-dependent RNA polymerase of SARS-CoV-2. Zinc also prevents the cytokine storm that takes place after the entry of SARS-CoV-2 into the cell, via its anti-inflammatory activity. The authors believe that no study has yet been published that has reviewed the trends, inventions, and patent literature of zinc compositions to treat/prevent COVID-19. Accordingly, this review has been written in order to fill this gap in the literature. The information about the clinical studies and the published patents/patent applications was retrieved from different databases. This review covers patent literature on zinc compositions up to 31 January 2022. Many important patents/patent applications for zinc-based compositions filed by innovative universities and industries were identified. The patent literature revealed zinc compositions in combination with zinc ionophores, antioxidants, antivirals, antibiotics, hydroxychloroquine, heparin, ivermectin, and copper. Most of these studies were supported by clinical trials. The patent literature supports the potential of zinc and its pharmaceutical compositions as possible treatments for COVID-19. The authors believe that countless zinc-based compositions are still unexplored, and there is an immense opportunity to evaluate a considerable number of the zinc-based compositions for use against COVID-19.     

The influence of resin infiltration system on enamel microhardness and surface roughness: An in vitro study

Objective

To investigate the effect of a resin infiltrant on the surface microhardness and roughness of healthy enamel and, as a subsidiary aim, to compare it with a fissure sealant.

Materials and methods

Twenty freshly extracted premolars were used. Sound enamel surfaces were treated with a resin infiltrant (Icon) or fissure sealant (Seal-Rite). The average roughness (R_a, μm) of the specimens was measured with a profilometer (Surtronic 10 Tylor Hobson). Surface hardness was determined by utilizing Vicker’s surface hardness (VHN) with a Micromet II Microhardness tester. Each specimen acted as its own control. Data were analyzed with 2-way analysis of variance (ANOVA), and mean values were compared with independent t-test. All analyses were performed with the SPSS program version 16 (USA). Differences with a P-value of ⩽0.05 were considered statistically significant.

Results

Comparison of enamel surfaces before and after application of resin infiltrant revealed no significant differences in surface hardness; however, enamel surfaces treated by infiltrant showed significantly higher VHN (244.0 ± 79.8) values than those treated with fissure sealant (37.5 ± 14.2). Surface roughness did not differ before and after application of either material to sound enamel. Enamel surfaces treated with fissure sealant (5.3 ± 1.4) were significantly smoother than those treated with infiltrant (6.9 ± 2.0).

Conclusion

Within the limitations of the study, the results showed that enamels treated with the resin infiltrant showed approximately the same microhardness and surface roughness as sound enamel, indicating that this material might be suitable for the treatment of enamel subsurface lesions.     

Sepsis in end-stage renal disease patients: are they at an increased risk of mortality?

ObjectivesThis study aims to examine the outcome of end-stage renal disease (ESRD) patients admitted with sepsis to the intensive care unit (ICU).DesignSingle centre, retrospective cohort studySettingThe study was conducted in the Intensive Care Department of King Abdulaziz Medical City, Riyadh, Saudi Arabia.ParticipantsData were extracted from a prospectively collected ICU database from 2002 to 2017. Patients were considered to have sepsis based on the sepsis-3 definition and were stratified into 2 groups based on the presence or absence of ESRD.Primary and secondary outcomesThe primary outcome of the study was in-hospital mortality. Secondary outcomes included ICU mortality, ICU and hospital lengths of stay, and mechanical ventilation duration.ResultsA total of 8803 patients were admitted to the ICU with sepsis during the study period. 730 (8.3%) patients had ESRD. 49.04% of ESRD patients with sepsis died within their hospital stay vs. 31.78% of non-ESRD patients. ESRD septic patients had 1.44 greater odds of dying within their hospital stay as compared to septic non-ESRD patients (OR 1.44, 95% CI 1.03–1.53). Finally, the predictors of hospital mortality in septic ESRD patients were found to be mechanical ventilation (OR 3.36; 95% CI 2.27–5.00), a history of chronic liver disease (OR 2.26; 95% CI 1.26–4.07), and use of vasopressors (OR 1.74; 95% CI 1.19–2.54). Among patients with ESRD, hospital mortality was higher in subgroups of patients with chronic cardiac (OR 1.86 (1.36–2.53) vs. 1.19 (0.96–1.47)) and chronic respiratory illnesses (OR 2.20 (1.52–3.20) vs. 1.21 (0.99–1.48)).ConclusionESRD patients admitted to the intensive care unit with sepsis are at greater odds of mortality compared to patients with non-ESRD. This risk is particularly increased if these patients have a concomitant history of chronic cardiac and respiratory illnesses.

Key Messages

• Sepsis and bacterial infections are very common in ESRD patients and following cardiovascular disease; sepsis is the second leading cause of death in patients with ESRD.
• This study aims to examine the outcome of patients with end-stage renal disease (ESRD) patients admitted with sepsis to the intensive care unit (ICU).
• The results of this study have shown that end-stage renal disease is associated with greater odds of ICU and hospital mortality among septic patients admitted to an intensive care unit.
• ESRD patients were also more likely to be started on vasopressors and mechanical ventilation.

     

Cyanobacteria and their toxins in treated-water storage reservoirs in Abha city, Saudi Arabia.

Occurrence of toxic cyanobacteria in drinking and recreational waters poses human health at risk as they can release potent toxins into the water. In the present study, open and covered treated-water storage reservoirs as well as their relevant tap waters in Abha city, Saudi Arabia, were surveyed for the presence of cyanobacteria and their toxins. The results revealed the contamination of most open reservoir and tap waters by algae and cyanobacteria, with an abundance of toxigenic species of cyanobacteria. Depending on the results of the Limulus amebocyte lysate (LAL) assay and enzyme linked immunosorbent assay (ELISA), endotoxins and microcystins (MCYSTs) were found in most open reservoir and tap waters at concentrations up to 32EUml(-1) and 0.3mugml(-1), respectively. The extracts of axenic cultures of most cyanobacterial species isolated from these reservoirs showed activity to LAL assay, with large endotoxin amounts obtained in Calothrix parietina (490EUg(-1)) and Phormidium tenue (210EUg(-1)). Based on ELISA and HPLC analysis for these extracts, only C. parietina can produce MCYSTs (202mugg(-1)) with a profile consisting of MCYST-RR and -LR. This study suggests that open treated-water storage reservoirs should be covered to prevent the presence of cyanobacteria and their toxins in such drinking and recreational waters.