Applications of photodynamic therapy in keratitis.

Keratitis is corneal inflammatory disease which may be caused by several reason such as an injury, allergy, as well as a microbial infection. Besides these, overexposure to ultraviolet light and unhygienic practice of contact lenses are also associated with keratitis. Based on the cause of keratitis, different lines of treatments are recommended. Photodynamic therapy is a promising approach that utilizes light activated compounds to instigate either killing or healing mechanism to treat various diseases including both communicable and non-communicable diseases. This review focuses on clinically-important patent applications and the recent literature for the use of photodynamic therapy against keratitis.

Lactase can target cellular differentiation of Acanthamoeba castellanii belonging to the T4 genotype.

The free living Acanthamoeba spp. are ubiquitous amoebae associated with potentially blinding disease known as Acanthamoeba keratitis (AK) and a fatal central nervous system infection granulomatous amoebic encephalitis (GAE). With the inherent ability of cellular differentiation, it can phenotypically transform to a dormant cyst form from an active trophozoite form. Acanthamoeba cysts are highly resistant to therapeutic agents as well as contact lens cleaning solutions. One way to tackle drug resistance against Acanthamoeba is by inhibiting the formation of cysts from trophozoites. The biochemical analysis showed that the major component of Acanthamoeba cyst wall is composed of carbohydrate moieties such as galactose and glucose. The disaccharide of galactose and glucose is lactose. In this study, we analyzed the potential of lactase enzyme to target carbohydrate moieties of cyst walls. Amoebicidal assessment showed that lactase was ineffective against trophozoite of A. castellanii but enhanced amoebicidal effects of chlorhexidine. The lactase enzyme did not show any toxicity against normal human keratinocyte cells (HaCaT) at the tested range. Hence, lactase can be used for further assessment for development of potential therapeutic agents in the management of Acanthamoeba infection as well as formulation of effective contact lens disinfectants.

Antibacterial effects of quercetagetin are significantly enhanced upon conjugation with chitosan engineered copper oxide nanoparticles.

The development of antibiotic alternatives that entail distinctive chemistry and modes of action is necessary due to the threat posed by drug resistance. Nanotechnology has gained increasing attention in recent years, as a vehicle to enhance the efficacy of existing antimicrobials. In this study, Chitosan copper oxide nanoparticles (CHI-CuO) were synthesized and were further loaded with Quercetagetin (QTG) to achieve the desired (CHI-CuO-QTG). Size distribution, zeta potential and morphological analysis were accomplished. Next, the developed CHI-CuO-QTG was assessed for synergistic antibacterial properties, as well as cytotoxic attributes. Bactericidal assays revealed that CHI-CuO conjugation showed remarkable effects and enhanced QTG effects against a range of Gram + ve and Gram - ve bacteria. The MIC50 of QTG against S. pyogenes was 107 µg/mL while CHI-CuO-QTG reduced it to 9 µg/mL. Similar results were observed when tested against S. pneumoniae. Likewise, the MIC50 of QTG against S. enterica was 38 µg/mL while CHI-CuO-QTG reduced it to 7 µg/mL. For E. coli K1, the MIC50 of QTG was 42 µg/mL while with CHI-CuO-QTG it was 23 µg/mL. Finally, the MIC50 of QTG against S. marcescens was 98 µg/mL while CHI-CuO-QTG reduced it to 10 µg/mL. Notably, the CHI-CuO-QTG nano-formulation showed limited damage when tested against human cells using lactate dehydrogenase release assays. Importantly, bacterial-mediated human cell damage was reduced by prior treatment of bacteria using drug nano-formulations. These findings are remarkable and clearly demonstrate that drug-nanoparticle formulations using nanotechnology is an important avenue in developing potential therapeutic interventions against microbial infections.

Gut microbiome of Crocodylus porosus and cellular stress: inhibition of nitric oxide, interleukin 1-beta, tumor necrosis factor-alpha, and prostaglandin E2 in cerebrovascular endothelial cells.

Crocodiles are renowned for their resilience and capacity to withstand environmental stressors, likely influenced by their unique gut microbiome. In this study, we determined whether selected gut bacteria of Crocodylus porosus exhibit anti-inflammatory effects in response to stress, by measuring nitric oxide release, interleukin 1-beta, tumor necrosis factor-alpha, and prostaglandin E2 in cerebrovascular endothelial cells. Using the Griess assay, the findings revealed that among several C. porosus gut bacterial isolates, the conditioned media containing the metabolites of two bacterial strains (CP27 and CP36) inhibited nitric oxide production significantly, in response to the positive control, i.e., taxol-treatment. Notably, CP27 and CP36 were more potent at reducing nitric oxide production than senloytic compounds (fisetin, quercetin). Using enzyme linked immunosorbent assays, the production of pro-inflammatory cytokines (IL-1ß, TNF-α, PGE2), was markedly reduced by treatment with CP27 and CP36, in response to stress. Both CP27 and CP36 contain a plethora of metabolites to exact their effects [(3,4-dihydroxyphenylglycol, 5-methoxytryptophan, nifedipine, 4-chlorotestosterone-17-acetate, 3-phenoxypropionic acid, lactic acid, f-Honaucin A, l,l-Cyclo(leucylprolyl), 3-hydroxy-decanoic acid etc.], indicative of their potential in providing protection against cellular stress. Further high-throughput bioassay-guided testing of gut microbial metabolites from crocodiles, individually as well as in combination, together with the underlying molecular mechanisms, in vitro and in vivo will elucidate their value in the rational development of innovative therapies against cellular stress/gut dysbiosis.

The increasing importance of the oral microbiome in periodontal health and disease.

Herein, the aim is to discuss the current knowledge of microbiome and periodontal diseases. Current treatment strategies include mechanical therapy such as root planing, scaling, deep pocket debridement and antimicrobial chemotherapy as an adjuvant therapy. Among promising therapeutic strategies, dental probiotics and oral microbiome transplantation have gained attention, and may be used to treat bacterial imbalances by competing with pathogenic bacteria for nutrients and adhesion surfaces, as well as probiotics targeting the gut microbiome. Development of strategies to prevent and treat periodontal diseases are warranted as both are highly prevalent and can affect human health. Further studies are necessary to better comprehend the microbiome in order to develop innovative preventative measures as well as efficacious therapies against periodontal diseases.

This paper discusses what we currently know about the microbiome and periodontal diseases. Plaque buildup can happen for various reasons, like eating sugary foods, changes in saliva and the microorganisms in the mouth and gut. To treat periodontal diseases, we currently use antimicrobial medications and scaling. For patients with periodontitis, root planing and deep pocket debridement are used. Dental probiotics are getting attention as a potential treatment option. They work by competing with harmful bacteria for nutrients and surfaces in the mouth, and there are also probiotics that target the gut microbiome.

Coronavirus and co-infections: A Saudi Arabian perspective.

Mortality due to infectious diseases continues to rise globally, despite advances in antimicrobial therapy and supportive care. This is evident with the occurrence of coronavirus disease 2019 (COVID-19) pandemic, instigated by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Saudi Arabia, an eminent country within the Arab region, has had significant impact during global pandemics, concomitant with the fact that millions of Muslims travel to Saudi Arabia for pilgrimages every year. Herein, we discuss the significance of SARS-CoV-1, SARS-CoV-2, as well as the Middle East respiratory syndrome coronavirus (MERS-CoV) in Saudi Arabia with particular reference to global transmission and/or emergence of new variants due to genetic mixing of different strains. Furthermore, we also discuss the role of Saudi Arabia with reference to novel emerging infectious diseases and re-emerging infections, such as Ebola, zika, and monkeypox, as well as in the context on coinfections. Future strategies to limit the spread of viral infections and the pivotal role of Saudi Arabia, are deliberated upon.

Can Acanthamoeba Harbor Monkeypox Virus?

Acanthamoeba is well known to host a variety of microorganisms such as viruses, bacteria, protozoa, and yeast. Given the recent number of cases of monkeypox infection, we speculate that amoebae may be aiding viral transmission to the susceptible hosts. Although there is no confirmatory evidence to suggest that Acanthamoeba is a host to monkeypox (a double-stranded DNA virus), the recent discovery of mimivirus (another double-stranded DNA virus) from Acanthamoeba, suggests that amoebae may shelter monkeypox virus. Furthermore, given the possible spread of monkeypox virus from animals to humans during an earlier outbreak, which came about after patients came in contact with prairie dogs, it is likely that animals may also act as mixing vessel between ubiquitously distributed Acanthamoeba and monkeypox virus, in addition to the environmental habitat that acts as an interface in complex interactions between diverse microorganisms and the host.

Selected Gut Bacteria from Water Monitor Lizard Exhibit Effects against Pathogenic Acanthamoeba castellanii Belonging to the T4 Genotype.

Water monitor lizards (WMLs) reside in unhygienic and challenging ecological surroundings and are routinely exposed to various pathogenic microorganisms. It is possible that their gut microbiota produces substances to counter microbial infections. Here we determine whether selected gut bacteria of water monitor lizards (WMLs) possess anti-amoebic properties using Acanthamoeba castellanii of the T4 genotype. Conditioned media (CM) were prepared from bacteria isolated from WML. The CM were tested using amoebicidal, adhesion, encystation, excystation, cell cytotoxicity and amoeba-mediated host cell cytotoxicity assays in vitro. Amoebicidal assays revealed that CM exhibited anti-amoebic effects. CM inhibited both excystation and encystation in A. castellanii. CM inhibited amoebae binding to and cytotoxicity of host cells. In contrast, CM alone showed limited toxic effects against human cells in vitro. Mass spectrometry revealed several antimicrobials, anticancer, neurotransmitters, anti-depressant and other metabolites with biological functions. Overall, these findings imply that bacteria from unusual places, such as WML gut, produce molecules with anti-acanthamoebic capabilities.

Antiamoebic Properties of Ceftriaxone and Zinc-Oxide-Cyclodextrin-Conjugated Ceftriaxone.

Acanthamoeba castellanii is a ubiquitous free-living amoeba capable of instigating keratitis and granulomatous amoebic encephalitis in humans. Treatment remains limited and inconsistent. Accordingly, there is a pressing need for novel compounds. Nanotechnology has been gaining attention for enhancing drug delivery and reducing toxicity. Previous work has shown that various antibiotic classes displayed antiamoebic activity. Herein, we employed two antibiotics: ampicillin and ceftriaxone, conjugated with the nanocarrier zinc oxide and ß-cyclodextrin, and tested them against A. castellanii via amoebicidal, amoebistatic, encystment, excystment, cytopathogenicity, and cytotoxicity assays at a concentration of 100 µg/mL. Notably, zinc oxide ß-cyclodextrin ceftriaxone significantly inhibited A. castellanii growth and cytopathogenicity. Additionally, both zinc oxide ß-cyclodextrin ceftriaxone and ceftriaxone markedly inhibited A. castellanii encystment. Furthermore, all the tested compounds displayed negligible cytotoxicity. However, minimal anti-excystment or amoebicidal effects were observed for the compounds. Accordingly, this novel nanoconjugation should be employed in further studies in hope of discovering novel anti-Acanthamoeba compounds.

Cytological Changes and Immunocytochemistry Expression of P53 in Oral Mucosa Among Waterpipe Users in the Kingdom of Saudi Arabia.

Objective In this study, we aimed to assess cytological changes and p53 expression in oral mucosa among waterpipe users in the Kingdom of Saudi Arabia (KSA). Methodology A case-control study was conducted in KSA from January to October 2022. Two cytologic oral smear samples each were taken from 500 volunteers; 300 were waterpipe users (case) while 200 did not use a waterpipe (control). They were then stained using the Papanicolaou staining procedure and immunocytochemical method to show the expression of P53. Results The interpretation of the Papanicolaou staining outcomes showed the presence of four results with different proportions: inflammation, infection, atypia, and keratinization. Cytological inflammation was identified among 77/300 (25.6%) waterpipe smokers, which was higher than that among non-users (12/200, 6%). The reverse cytological infection and atypia were also higher in waterpipe smokers compared with controls (9% vs. 4.5% and 4.3% vs. 0.5%, respectively), and keratinization was detected only in waterpipe users (3.6%) compared with controls. Waterpipe users had higher p53 protein expression than non-users. Conclusion Using a waterpipe is an effective way to change the oral mucosa. In atypia and keratinization, there was high p53 expression. These results could indicate that p53 is involved in both the change from normal to cancerous cells and the growth of new cells, but the presence or absence of p53 staining could not be used to predict the outcome of potentially cancerous oral mucosal lesions.

Imidazothiazole Derivatives Exhibited Potent Effects against Brain-Eating Amoebae.

Naegleria fowleri (N. fowleri) is a free-living, unicellular, opportunistic protist responsible for the fatal central nervous system infection, primary amoebic meningoencephalitis (PAM). Given the increase in temperatures due to global warming and climate change, it is estimated that the cases of PAM are on the rise. However, there is a current lack of awareness and effective drugs, meaning there is an urgent need to develop new therapeutic drugs. In this study, the target compounds were synthesized and tested for their anti-amoebic properties against N. fowleri. Most compounds exhibited significant amoebicidal effects against N. fowleri; for example, 1h, 1j, and 1q reduced N. fowleri's viability to 15.14%, 17.45% and 28.78%, respectively. Furthermore, the majority of the compounds showed reductions in amoeba-mediated host death. Of interest are the compounds 1f, 1k, and 1v, as they were capable of reducing the amoeba-mediated host cell death to 52.3%, 51%, and 56.9% from 100%, respectively. Additionally, these compounds exhibit amoebicidal properties as well; they were found to decrease N. fowleri's viability to 26.41%, 27.39%, and 24.13% from 100%, respectively. Moreover, the MIC50 values for 1e, 1f, and 1h were determined to be 48.45 µM, 60.87 µM, and 50.96 µM, respectively. Additionally, the majority of compounds were found to exhibit limited cytotoxicity, except for 1l, 1o, 1p, 1m, 1c, 1b, 1zb, 1z, 1y, and 1x, which exhibited negligible toxicity. It is anticipated that these compounds may be developed further as effective treatments against these devastating infections due to brain-eating amoebae.

The Pivotal Role of the Gut Microbiome in Colorectal Cancer.

Colorectal cancer is the third most diagnosed cancer worldwide and the second most prevalent cause of cancer-related mortality. It is believed that alterations within the gut microbiome may impact the development and progression of cancer. Additionally, the diet an individual maintains and the amount of alcohol consumed can alter the microbiome, thus impacting the development of colorectal cancer. A diet focused on fiber intake is considered beneficial, as it contains short-chain fatty acids such as butyrate, which have antitumor properties. Furthermore, current treatment strategies, such as chemotherapy, have various side effects. In this review, we discuss the role of the gut microbiome and oral bacteria in relation to colorectal cancer. We also deliberate on the role of diet and alcohol consumption in the development of colorectal cancer. Moreover, the influence of the various metabolites within the gut and the importance of gut inflammation in the development of colorectal cancer are explained. Finally, potential therapies such as fecal microbiota transfer and post/prebiotics are elaborated on. To further comprehend risk factors in the development of colorectal cancer, future studies are warranted to determine the precise mechanisms of action between the gut microbiome and carcinogenesis in order to develop therapies that may target gut microbial dysbiosis.

The Gut Microbiome and Female Health.

The possession of two X chromosomes may come with the risk of various illnesses, females are more likely to be affected by osteoarthritis, heart disease, and anxiety. Given the reported correlations between gut microbiome dysbiosis and various illnesses, the female gut microbiome is worthy of exploration. Herein, we discuss the composition of the female gut microbiota and its dysbiosis in pathologies affecting the female population. Using PubMed, we performed a literature search, using key terms, namely: "gut microbiome", "estrogen", "menopause", "polycystic ovarian syndrome", "pregnancy", and "menstruation". In polycystic ovarian syndrome (PCOS), the abundance of Bacteroides vulgatus, Firmicutes, Streptococcus, and the ratio of Escherichia/Shigella was found to be increased while that of Tenericutes ML615J-28, Tenericutes 124-7, Akkermansia, Ruminococcaceae, and Bacteroidetes S24-7 was reduced. In breast cancer, the abundance of Clostridiales was enhanced, while in cervical cancer, Prevotella, Porphyromonas, and Dialister were enhanced but Bacteroides, Alistipes, and members of Lachnospiracea, were decreased. In ovarian cancer, Prevotella abundance was increased. Interestingly, the administration of Lactobacillus acidophilus, Bifidobacterium bifidum, Lactobacillus reuteri, and Lactobacillus fermentum ameliorated PCOS symptoms while that of a mix of Bifidobacterium lactis W51, Bifidobacterium bifidum W23, Lactobacillus brevis W63, Bifidobacterium lactis W52, Lactobacillus salivarius W24, Lactobacillus acidophilus W37, Lactococcus lactis W19, Lactobacillus casei W56, and Lactococcus lactis W58 alleviated vascular malfunction and arterial stiffness in obese postmenopausal women, and finally, while further research is needed, Prevotella maybe protective against postmenopausal bone mass loss. As several studies report the therapeutic potential of probiotics and since the gut microbiota of certain female pathological states has been relatively characterized, we speculate that the administration of certain bacterial species as probiotics is warranted, as novel independent or adjunct therapies for various female pathologies.

Seroprevalence of IgM and IgG Against SARS-CoV-2 after Two Doses of Pfizer-BioNTech COVID-19 Vaccine in Women with Breast Cancer.

BACKGROUND: This study evaluates the seroprevalence of immunoglobulin M (IgM) and G (IgG) antibodies against SARS-CoV-2 after two doses of Pfizer-BioNTech COVID-19 vaccination from women with breast cancer in Jazan city Kingdom of Saudi Arabia, antibody detections were performed one month and three months after the administration of the second dose. METHODS: Overall, 103 breast cancer patients were included. Individuals who had had two doses of Pfizer-BioNTech vaccine, patients who were earlier diagnosed with COVID-19 infection, had not finalized immunization plan, or who received the second dose recently were excluded from the study. The antibodies detection test was run according to the manufacturer's directions of Viva Diag™ SARS-CoV-2 IgM/IgG Rapid Test (COVID-19 IgM/IgG Rapid Test). RESULTS: This study included 62 (60.2%) and 41 (39.8%) patients with invasive ductal carcinoma and invasive lobular carcinoma, respectively. The age, median and interquartile range (IQR) was 54.0 (26) years. Regarding reactivity of antibodies, after one month IgM antibody showed 64 (62.1%) positive and 39 (37.9%) negative while IgG antibody showed positive results in all patients. After three months IgM antibody showed 44 (42.7%) positive and 59 (57.3%) negative, while IgG showed 87 (84.5%) positive and 16 (15.5%) negative. There were significant differences in the IgM and IgG seropositivity. There were 19.3% patients with ductal carcinoma who were positive and then turned negative versus 17.7% who were positive and then turned negative, respectively (p < 0.001). There were significant differences in IgM antibody positivity among different age groups. CONCLUSIONS: Our results recommend the importance of screening for an antibody response for breast cancer patient after immunization in order to reveal persons who need early and late extra enhancing vaccine dose. Upcoming studies recommended to estimate different methods that raise cancer patients' immune response.

Effect of Microgravity on the Gut Microbiota Bacterial Composition in a Hindlimb Unloading Model.

We utilised a ground-based microgravity hindlimb unloading (HU) mouse model to elucidate the gut microbiota bacterial changes in mice under a simulated microgravity environment. Four-month-old, male C57/Bl6 mice were randomly divided into ground-based controls and the HU groups and kept under controlled environmental conditions. For the microgravity environment, the mice were suspended in special cages individually for 20 days. At the end of the suspension, the mice were sacrificed; gut dissections were performed, followed by a metagenomic analysis of bacterial species, which was carried out by extracting DNA and 16S rRNA analysis. The results revealed that the gut bacterial communities of mice under gravity and microgravity were different. Notably, our findings revealed differences in the bacterial community structure. Around 449 bacterial OTUs were specific to mice kept under normal gravity versus 443 bacterial OTUs under microgravity conditions. In contrast, 694 bacterial OTUs were common to both groups. When the relative abundance of taxa was analyzed, Bacteroidetes dominated the gut (64.7%) of normal mice. Conversely, mice in the microgravity environment were dominated by Firmicutes (42.7%), and the relative abundance of Bacteroidetes differed significantly between the two groups (p < 0.05). The distribution of Muribaculaceae between normal mice versus microgravity mice was significantly different, at 62% and 36.4%, respectively (p < 0.05). Furthermore, a significant decrease in 11 bacteria was observed in mice under simulated microgravity, including Akkermansia muciniphila, Eubacterium coprostanoligenes, Bacteroides acidifaciens, Clostridium leptum, Methylorubrum extorquens, Comamonas testosterone, Desulfovibrio fairfieldensis, Bacteroides coprocola, Aerococcus urinaeequi, Helicobacter hepaticus, and Burkholderiales. Further studies are needed to elucidate gut bacterial metabolites of these identified bacterial species in microgravity conditions and normal environment. Notably, the influence of these metabolites on obesity, neuroprotection, musculoskeletal and cardiovascular dysfunction, longevity, inflammation, health, and disease in astronauts ought to be investigated and will be important in developing procedures against adverse effects in astronauts following space travel.

Zinc Oxide Nanoconjugates against Brain-Eating Amoebae.

Naegleria fowleri and Balamuthia mandrillaris are opportunistic protists, responsible for fatal central nervous system infections such as primary amoebic meningoencephalitis (PAM) and granulomatous amoebic encephalitis (GAE) with mortality rates higher than 90%. Threatening a rise in cases is the increase in temperature due to global warming. No effective treatment is currently available. Herein, nanotechnology was used to conjugate Zinc oxide with Ampicillin, Ceftrixon, Naringin, Amphotericin B, and Quericitin, and the amoebicidal activity and host cell cytotoxicity of these resulting compounds were investigated. The compounds ZnO-CD-AMPi, ZnO-CD-CFT, ZnO-CD-Nar, ZnO-CD-AMB, and ZnO-CD-QT were found to reduce N. fowleri viability to 35.5%, 39.6%, 52.0%, 50.8%, 35.9%, and 69.9%, respectively, and B. mandrillaris viability to 40.9%, 48.2%, 51.6%, 43.8%, and 62.4%, respectively, when compared with their corresponding controls. Furthermore, the compounds reduced N. fowleri-mediated and B. mandrillaris-mediated host cell death significantly. Additionally, the compounds showed limited cytotoxicity against human cells; cell toxicity was 35.5%, 36.4%, 30.9%, 36.6%, and 35.6%, respectively, for the compounds ZnO-CD-AMPi, ZnO-CD-CFT, ZnO-CD-Nar, ZnO-CD-AMB, and ZnO-CD-QT. Furthermore, the minimum inhibitory concentrations to inhibit amoeba growth by 50% were determined for N. fowleri and B. mandrillaris. The MIC50 for N. fowleri were determined to be 69.52 µg/mL, 82.05 µg/mL, 88.16 µg/mL, 95.61 µg/mL, and 85.69 µg/mL, respectively; the MIC50 of the compounds for B. mandrillaris were determined to be 113.9 µg/mL, 102.3 µg/mL, 106.9 µg/mL, 146.4 µg/mL, and 129.6 µg/mL, respectively. Translational research to further develop therapies based on these compounds is urgently warranted, given the lack of effective therapies currently available against these devastating infections.

Antiamoebic Activity of Imidazothiazole Derivatives against Opportunistic Pathogen Acanthamoeba castellanii.

We examined the antiamoebic effect of several imidazothiazole derivatives on Acanthamoeba castellanii of the T4 genotype. Trypan blue exclusion assays and haemocytometer counting were used to determine the reduction in A. castellanii trophozoite proliferation, in response to treatment with these compounds. To determine the effects of these compounds on host cells, lactate dehydrogenase assay was performed using HeLa cell lines. Amoebicidal assays revealed that the tested compounds at concentrations of 50 µM significantly inhibited amoebae trophozoites compared to controls. Compounds 1m and 1zb showed the highest amoebicidal effects eradicating 70% and 67% of A. castellanii, respectively. The compounds blocked both the encystation and excystation process in A. castellanii. Compounds 1m and 1zb blocked 61% and 55%, respectively, of amoeba binding to human cells. Moreover, the compounds showed minimal cytotoxic effects against host cells and considerably reduced amoeba-mediated host cell death. Overall, our study revealed that compounds 1m and 1zb have excellent antiamoebic potential, and should be considered in the development of curative antiamoebic medications in future studies. Further work is critical to determine the translational value of these findings.

The Use of Gut Microbial Modulation Strategies as Interventional Strategies for Ageing.

Gut microbial composition codevelops with the host from birth and is influenced by several factors, including drug use, radiation, psychological stress, dietary changes and physical stress. Importantly, gut microbial dysbiosis has been clearly associated with several diseases, including cancer, rheumatoid arthritis and Clostridium difficile-associated diarrhoea, and is known to affect human health and performance. Herein, we discuss that a shift in the gut microbiota with age and reversal of age-related modulation of the gut microbiota could be a major contributor to the incidence of numerous age-related diseases or overall human performance. In addition, it is suggested that the gut microbiome of long-lived animals such as reptiles should be investigated for their unique properties and contribution to the potent defense system of these species could be extrapolated for the benefit of human health. A range of techniques can be used to modulate the gut microbiota to have higher abundance of "beneficial" microbes that have been linked with health and longevity.

Detection of erythroid progenitors and erythrocytopathies in patients with severe COVID-19 disease.

OBJECTIVES: To assess the effect of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection on erythropoiesis and red blood cells (RBC) surface markers by evaluating erythroid progenitor cells (CD [cluster of differentiation]71+/CD235a+) and RBC surface markers (CD235a and CD36), together with various hematological parameters. METHODS: This case-control study includes 47 participants recruited in the study: 30 patients with coronavirus disease 2019 (COVID-19) and 17 healthy individuals. The COVID-19 patients were recruited from the intensive care unit (ICU) of various hospitals in Makkah, Saudi Arabia. Blood samples were collected during July and September 2021. Red blood cells indices were measured using a CBC analyzer. The expression of CD235a, CD71, and CD36 was obtained using flow cytometry technique. The unpaired t-test was conducted to evaluate the differences in these markers in COVID-19 patients and healthy individuals. RESULTS: The data showed that more than half of the COVID-19 patients were anemic (64%). Expansion of erythroid progenitors (CD71+/CD235a+) was detected in the COVID-19 patients. Analysis of the expression of RBC surface markers, such as CD235a and CD36, showed that SARS-CoV-2 was associated with significantly higher expression of these markers in COVID-19 patients. CONCLUSION: Severe acute respiratory syndrome coronavirus-2 promoted the expansion of erythroid progenitors in the peripheral blood of COVID-19 patients. In addition, the expression of RBC surface markers was higher in COVID-19 patients. The expansion of erythroid progenitors and alteration of RBC surface markers can contribute to erythrocytopathies observed in severe COVID-19 patients and can therefore be used as prognostic factors.

Novel Sources of Bioactive Molecules: Gut Microbiome of Species Routinely Exposed to Microorganisms.

The development of novel bioactive molecules is urgently needed, especially with increasing fatalities occurring due to infections by bacteria and escalating numbers of multiple-drug-resistant bacteria. Several lines of evidence show that the gut microbiome of cockroaches, snakes, crocodiles, water monitor lizards, and other species may possess molecules that are bioactive. As these animals are routinely exposed to a variety of microorganisms in their natural environments, it is likely that they have developed methods to counter these microbes, which may be a contributing factor in their persistence on the planet for millions of years. In addition to the immune system, the gut microbiota of a host may thwart colonization of the gastro-intestine by pathogenic and/or foreign microorganisms through two mechanisms: (i) production of molecules with antibacterial potential targeting foreign microorganisms, or (ii) production of molecules that trigger host immunity targeting foreign microorganisms that penetrate the host. Herein, we discuss and deliberate on the current literature examining antibacterial activities that stem from the gut bacteria of animals such as crocodiles, cockroaches, and water monitor lizards, amongst other interesting species, which likely encounter a plethora of microorganisms in their natural environments. The overall aim is to unveil a potential library of novel bioactive molecules for the benefit of human health and for utilization against infectious diseases.