Current Knowledge about Gastric Microbiota with Special Emphasis on Helicobacter pylori-Related Gastric Conditions.

The gastric milieu, because of its very low acidic pH, is very harsh for bacterial growth. The discovery of Helicobacter pylori (H.p.) has opened a new avenue for studies on the gastric microbiota, thus indicating that the stomach is not a sterile environment. Nowadays, new technologies of bacterial identification have demonstrated the existence of other microorganisms in the gastric habitat, which play an important role in health and disease. This bacterium possesses an arsenal of compounds which enable its survival but, at the same time, damage the gastric mucosa. Toxins, such as cytotoxin-associated gene A, vacuolar cytotoxin A, lipopolysaccharides, and adhesins, determine an inflammatory status of the gastric mucosa which may become chronic, ultimately leading to a gastric carcinoma. In the initial stage, H.p. persistence alters the gastric microbiota with a condition of dysbiosis, predisposing to inflammation. Probiotics and prebiotics exhibit beneficial effects on H.p. infection, and, among them, anti-inflammatory, antioxidant, and antibacterial activities are the major ones. Moreover, the association of probiotics with prebiotics (synbiotics) to conventional anti-H.p. therapy contributes to a more efficacious eradication of the bacterium. Also, polyphenols, largely present in the vegetal kingdom, have been demonstrated to alleviate H.p.-dependent pathologies, even including the inhibition of tumorigenesis. The gastric microbiota composition in health and disease is described. Then, cellular and molecular mechanisms of H.p.-mediated damage are clarified. Finally, the use of probiotics, prebiotics, and polyphenols in experimental models and in patients infected with H.p. is discussed.

Healthy Diets and Lifestyles in the World: Mediterranean and Blue Zone People Live Longer. Special Focus on Gut Microbiota and Some Food Components.

Longevity has been associated with healthy lifestyles, including some dietary regimens, such as the Mediterranean diet (MedDiet) and the Blue Zone (BZ) diets. MedDiet relies on a large consumption of fruit, vegetables, cereals, and extra-virgin olive oil, with less red meat and fat intake. Four major BZ have been recognized in the world, namely, Ogliastra in Sardinia (Italy), Ikaria (Greece), the Peninsula of Nicoya (Costa Rica), and Okinawa (Japan). Extreme longevity in these areas has been associated with correct lifestyles and dietary regimens. Fibers, polyphenols, beta-glucans, and unsaturated fatty acids represent the major constituents of both MedDiet and BZ diets, given their anti-inflammatory and antioxidant activities. Particularly, inhibition of the NF-kB pathway, with a reduced release of pro-inflammatory cytokines, and induction of T regulatory cells, with the production of the anti-inflammatory cytokine, interleukin- 10, are the main mechanisms that prevent or attenuate the "inflammaging." Notably, consistent physical activity, intense social interactions, and an optimistic attitude contribute to longevity in BZD areas. Commonalities and differences between MedDIet and BZ diets will be outlined, with special reference to microbiota and food components, which may contribute to longevity.

Oral microbiota in human health and disease: A perspective.

The evolution of medical knowledge about oral microbiota has increased awareness of its important role for the entire human body health. A wide range of microbial species colonizing the oral cavity interact both with each other and with their host through complex pathways. Usually, these interactions lead to a harmonious coexistence (i.e. eubiosis). However, several factors - including diet, poor oral hygiene, tobacco smoking, and certain medications, among others - can disrupt this weak homeostatic balance (i.e. dysbiosis) with potential implications on both oral (i.e. development of caries and periodontal disease) and systemic health. This article is thus aimed at providing an overview on the importance of oral microbiota in mediating several physiological and pathological conditions affecting human health. In this context, strategies based on oral hygiene and diet as well as the role of probiotics supplementation are discussed.

Crosstalk between the Resident Microbiota and the Immune Cells Regulates Female Genital Tract Health.

The female genital tract (FGT) performs several functions related to reproduction, but due to its direct exposure to the external environment, it may suffer microbial infections. Both the upper (uterus and cervix) and lower (vagina) FGT are covered by an epithelium, and contain immune cells (macrophages, dendritic cells, T and B lymphocytes) that afford a robust protection to the host. Its upper and the lower part differ in terms of Lactobacillus spp., which are dominant in the vagina. An alteration of the physiological equilibrium between the local microbiota and immune cells leads to a condition of dysbiosis which, in turn, may account for the outcome of FGT infection. Aerobic vaginitis, bacterial vaginosis, and Chlamydia trachomatis are the most frequent infections, and can lead to severe complications in reproduction and pregnancy. The use of natural products, such as probiotics, polyphenols, and lactoferrin in the course of FGT infections is an issue of current investigation. In spite of positive results, more research is needed to define the most appropriate administration, according to the type of patient.

The Crosstalk between Gut Microbiota and Nervous System: A Bidirectional Interaction between Microorganisms and Metabolome.

Several studies have shown that the gut microbiota influences behavior and, in turn, changes in the immune system associated with symptoms of depression or anxiety disorder may be mirrored by corresponding changes in the gut microbiota. Although the composition/function of the intestinal microbiota appears to affect the central nervous system (CNS) activities through multiple mechanisms, accurate epidemiological evidence that clearly explains the connection between the CNS pathology and the intestinal dysbiosis is not yet available. The enteric nervous system (ENS) is a separate branch of the autonomic nervous system (ANS) and the largest part of the peripheral nervous system (PNS). It is composed of a vast and complex network of neurons which communicate via several neuromodulators and neurotransmitters, like those found in the CNS. Interestingly, despite its tight connections to both the PNS and ANS, the ENS is also capable of some independent activities. This concept, together with the suggested role played by intestinal microorganisms and the metabolome in the onset and progression of CNS neurological (neurodegenerative, autoimmune) and psychopathological (depression, anxiety disorders, autism) diseases, explains the large number of investigations exploring the functional role and the physiopathological implications of the gut microbiota/brain axis.

The ancient roots of dentistry in the Mediterranean civilizations: between Etruscan and Greek traditions up to the time of imperial Rome.

Etruscans, people living in Etruria (Umbria and Tuscany, Italy), were the first to make dentures and false teeth, from 700 BCE onwards. The aim of this study was to investigate, through archaeological and anthropological records, the Etruscans ability in dental practice to understand better Greek's influence on their medical knowledge and, subsequently, the transmission of their medical expertise to Romans. We extensively searched literature to find out references in previous studies on Etruscan medical and dental practice by using keywords such as "Etruscan medicine" and "Etruscan dentistry." We selected various historical papers, from the ancient age texts of 5th century to 2020, which best focused on the review's purpose. Etruscan civilization was influenced by Greek's culture throughout Italian colonies and later "merge" into Greek-Roman culture. Their medical practice based on a mixture of mythology, religion, and technical abilities, especially regarding metalworking. Archaeological remains show a great competence in creating dental prosthesis and in treatment of oral diseases. The results of this paper provide an evident contribution to the knowledge of Etruscan culture, still largely unknown by an anthropological point of view, and their strong relationship with the Greeks colonies, in a profitable cultural exchange.

Ancient herbal therapy: A brief history of Panax ginseng.

Ginseng was the most revered of the herbs in ancient times in China, Korea, Japan, America. Ginseng was discovered over 5000 years ago in the mountains of Manchuria, China. References to ginseng are found in books dating back more than two millennia. It is revered by the Chinese people as it is considered a herb for everything use and therefore for a wide range of diseases (currently its Latin name derived from the Greek panacea, meanings, that is, for everything). So, it was used exclusively by the Chinese Emperor's, and they were willing to pay the price without problems. Increasing its fame, ginseng brought a flourishing international trade that allowed Korea to supply China with silk and medicines in exchange for wild ginseng and later along with what grows in America.

About Functional Foods: The Probiotics and Prebiotics State of Art.

Poor diet, obesity and a sedentary lifestyle have a significant impact on natural microbiota disorders; specifically, the intestinal one. This in turn can lead to a multitude of organ dysfunctions. The gut microbiota contains more than 500 species of bacteria and constitutes 95% of the total number of cells in the human body, thus contributing significantly to the host's resistance to infectious diseases. Nowadays, consumers have turned to purchased foods, especially those containing probiotic bacteria or prebiotics, that constitute some of the functional food market, which is constantly expanding. Indeed, there are many products available that incorporate probiotics, such as yogurt, cheese, juices, jams, cookies, salami sausages, mayonnaise, nutritional supplements, etc. The probiotics are microorganisms that, when taken in sufficient amounts, contribute positively to the health of the host and are the focus of interest for both scientific studies and commercial companies. Thus, in the last decade, the introduction of DNA sequencing technologies with subsequent bioinformatics processing contributes to the in-depth characterization of the vast biodiversity of the gut microbiota, their composition, their connection with the physiological function-known as homeostasis-of the human organism, and their involvement in several diseases. Therefore, in this study, we highlighted the extensive investigation of current scientific research for the association of those types of functional foods containing probiotics and prebiotics in the diet and the composition of the intestinal microbiota. As a result, this study can form the foundation for a new research path based on reliable data from the literature, acting a guide in the continuous effort to monitor the rapid developments in this field.

Non-Surgical Therapy and Oral Microbiota Features in Peri-Implant Complications: A Brief Narrative Review.

The therapeutic discretion in cases of peri-implantitis should take into account the limits and advantages of specific therapeutic itineraries tailored according to each clinical case and each individual patient. This type of oral pathology emphasizes the complex classification and diagnostic issues coupled with the need for targeted treatments, in light of the oral peri-implant microbiota changes. This review highlights the current indications for the non-surgical treatment of peri-implantitis, describing the specific therapeutic efficacy of different approaches and discussing the more appropriate application of single non-invasive therapies The non-surgical treatment choice with antiseptics or antibiotics (single or combined, local, or systemic) for short courses should be considered on a case-by-case basis to minimize the incidence of side effects and concomitantly avoid disease progression.

Subversion of the Oral Microbiota and Induction of Immune-Mediated Systemic Inflammation with Special Reference to Periodontitis: Current Knowledge and Perspectives.

Under steady-state circumstances, the oral microbiota is in equilibrium with host tissues, thus contributing to local and systemic health. Any interruption of such equilibrium leads to a condition of dysbiosis with the proliferation of oral pathogens able to cause gingivitis and periodontal disease. The mechanisms of periodontitis will be described, mostly emphasizing the noxious effects exerted by oral pathogens on the periodontium either directly or indirectly via the release of an array of mediators, even including pro-inflammatory cytokines, chemokines, and enzymes. The persistence of local inflammation ultimately leads to systemic inflammation; therefore, the link between periodontitis and obesity, diabetes and cardiovascular disease will be elucidated. Some natural compounds, such as polyphenols, prebiotics, and probiotics, will be discussed for their ability to exert anti-inflammatory and anti-oxidant activities in the context of the inflamed buccal cavity and systemically, as well as for their modulation of the altered gum-gut microbiota.

Antibiotic Resistance to Mycobacterium tuberculosis and Potential Use of Natural and Biological Products as Alternative Anti-Mycobacterial Agents.

BACKGROUND: Tuberculosis (TB) is an infectious disease caused by the bacillus Mycobacterium tuberculosis (Mtb). TB treatment is based on the administration of three major antibiotics: isoniazid, rifampicin, and pyrazinamide. However, multi-drug resistant (MDR) Mtb strains are increasing around the world, thus, allowing TB to spread around the world. The stringent response is demonstrated by Mtb strains in order to survive under hostile circumstances, even including exposure to antibiotics. The stringent response is mediated by alarmones, which regulate bacterial replication, transcription and translation. Moreover, the Mtb cell wall contributes to the mechanism of antibiotic resistance along with efflux pump activation and biofilm formation. Immunity over the course of TB is managed by M1-macrophages and M2-macrophages, which regulate the immune response against Mtb infection, with the former exerting inflammatory reactions and the latter promoting an anti-inflammatory profile. T helper 1 cells via secretion of interferon (IFN)-gamma, play a protective role in the course of TB, while T regulatory cells secreting interleukin 10, are anti-inflammatory. Alternative therapeutic options against TB require further discussion. In view of the increasing number of MDR Mtb strains, attempts to replace antibiotics with natural and biological products have been object of intensive investigation. Therefore, in this review the anti-Mtb effects exerted by probiotics, polyphenols, antimicrobial peptides and IFN-gamma will be discussed. All the above cited compounds are endowed either with direct antibacterial activity or with anti-inflammatory and immunomodulating characteristics.

Current Issues and Perspectives in Antimicrobials use in Dental Practice.

The complexity of the use of antimicrobials for dental use (such as antibiotics) is directly related not only to the mode of onset of an oral infection (linked to numerous factors of local causality and comorbidity) but also to the predisposing risk for the general health of the patient with putative serious consequences related to the neck district. The abuse and misuse of antibiotics may lead to resistance to certain bacterial strains. In this regard, the evaluation of the risk/benefit of their use (especially in pregnant women) can be divided into two phases: risk analysis and subsequently risk management for the benefit of the patient for the oral pathology to be prevented or treated, respectively. This study seeks to focus on the issues and management of patients with certain antimicrobials during dental practice, placing special emphasis on new classes of antibiotics.

Biomolecular Mechanisms of Autoimmune Diseases and Their Relationship with the Resident Microbiota: Friend or Foe?

The use of innovative approaches to elucidate the pathophysiological mechanisms of autoimmune diseases, as well as to further study of the factors which can have either a positive or negative effect on the course of the disease, is essential. In this line, the development of new molecular techniques and the creation of the Human Genome Program have allowed access to many more solutions to the difficulties that exist in the identification and characterization of the microbiome, as well as changes due to various factors. Such innovative technologies can rekindle older hypotheses, such as molecular mimicry, allowing us to move from hypothesis to theory and from correlation to causality, particularly regarding autoimmune diseases and dysbiosis of the microbiota. For example, Prevotella copri appears to have a strong association with rheumatoid arthritis; it is expected that this will be confirmed by several scientists, which, in turn, will make it possible to identify other mechanisms that may contribute to the pathophysiology of the disease. This article seeks to identify new clues regarding similar correlations between autoimmune activity and the human microbiota, particularly in relation to qualitative and quantitative microbial variations therein.

Venoms and Poisonings during the Centuries: A Narrative Review.

The first traces of man's of poison use date back to ten thousand years ago since the last period of the Paleolithic era. Man used poison for hunting and defense. Indeed, in the second half of the 19th century, arrows made from the bones of animals characterized by particular grooves were found in some caves. In ancient Greece, the term pharmakon (φάρµακον) had a double meaning: remedy for therapy and venom. This is the period in which humans became aware of the fact that poison cannot be defined simply as a substance capable of changing the properties of things. Poison is very frequently mentioned in the history of the Roman Empire, and its use continued through the Renaissance and even during the modern era. Poison was the protagonist in multiple political intrigues of power and is one of the most used lethal weapons over the years. Thought of as the optimal solution for a perfect murder, the poison has a long history. Its success is due to the invisible, untraceable, and often unpunished death it causes.

Efficacy of bioactivated anticalculus toothpaste on oral health: a single-blind, parallel-group clinical study.

BACKGROUND: Current epidemiologic studies have confirmed the widespread presence of calculus in teenagers and adults of all ages. Among the multiple anticalculus strategies that have been proposed over the years inhibition of crystal growth has been the most attractive. Current formulations in anticalculus toothpastes and mothwash, utilize either hydroxyapatite or various pyrophosphate combinations. This study aimed to analyze the efficacy of an anticalculus tooth paste in combination or not with a mouth rinse. METHODS: Patients (totally 40) used a pyrophosphate-based toothpaste containing tetrapotassium pyrophosphate, pentasodium triphosphate, xylitol, hydroxyapatite, citric acid, and calcium carbonate (group A) in combination, with a mouth rinse containing an association of pentasodium triphosphate, tetrapotassium pyrophosphate and citric acid (group B). A range of parameters were measured for: saliva pH, Volpe Manhold Calculus Index (VMI), Gingival Index (GI), and Plaque Index (PI). RESULTS: The test mouth rinse group B showd reductions in VMI, GI, PI, and increases in pH levels, after using the combination of toothpaste and mouth rinse. No changes in the mucosa or teeth were observed in both groups. Patients perceived that the comitation of products was more effective. CONCLUSIONS: The results from the three-month calculus examination indicated that both the tested products, modified positively clincal parameters and salivary pH. Moreover, the use of the tested products was not associated with any adverse effects.

The war against bacteria, from the past to present and beyond.

INTRODUCTION: The human defense against microorganisms dates back to the ancient civilizations, with attempts to use substances from vegetal, animal, or inorganic origin to fight infections. Today, the emerging threat of multidrug-resistant bacteria highlights the consequences of antibiotics inappropriate use, and the urgent need for novel effective molecules. METHODS AND MATERIALS: We extensively researched on more recent data within PubMed, Medline, Web of Science, Elsevier's EMBASE, Cochrane Review for the modern pharmacology in between 1987 - 2021. The historical evolution included a detailed analysis of past studies on the significance of medical applications in the ancient therapeutic field. AREAS COVERED: We examined the history of antibiotics development and discovery, the most relevant biochemical aspects of their mode of action, and the biomolecular mechanisms conferring bacterial resistance to antibiotics. EXPERT OPINION: The list of pathogens showing low sensitivity or full resistance to most currently available antibiotics is growing worldwide. Long after the 'golden age' of antibiotic discovery, the most novel molecules should be carefully reserved to treat serious bacterial infections of susceptible bacteria. A correct diagnostic and therapeutic procedure can slow down the spreading of nosocomial and community infections sustained by multidrug-resistant bacterial strains.

Metals Biotribology and Oral Microbiota Biocorrosion Mechanisms.

During the last decades, metal-based biomaterials have been extensively explored to be used as biocompatible metals for biomedical applications, owing to their superior mechanical properties and corrosion resistance. Consequently, for long-term implanted medical devices, to assure the biomaterials' reliability, functionality, and biocompatibility, studying the various bio-tribological damage mechanisms to obtain the optimum properties is one of the most important goals. In this review, we consider the most important metal-based biomaterials such as stainless steel, alloys of titanium (Ti), cobalt-chromium (Co-Cr), and Nichel-Titatium (Ni-Ti), as well Magnesium (Mg) alloys and with Tantalum (Ta), emphasizing their characteristics, clinical applications, and deterioration over time. The influence of metal elements on biological safety, including significant effects of metal-based biomaterials in dentistry were discussed, considering the perspectives of surface, mechanical properties, corrosion behaviors, including interactions, bio-mechanisms with tissues, and oral environments. In addition, the role of the oral microbiota was explored due to its role in this erosion condition, in order to further understand the mechanism of metal-based biomaterials implanted on the microflora balance of aerobic and anaerobic bacteria in an oral environment.

Overview of Candida albicans and Human Papillomavirus (HPV) Infection Agents and their Biomolecular Mechanisms in Promoting Oral Cancer in Pediatric Patients.

Oral carcinoma represents one of the most common malignancies worldwide. Oral squamous cell carcinomas (OSCCs) account over 90% of all oral malignant tumors and are characterized by high mortality in the advanced stages. Early diagnosis is often a challenge for its ambiguous appearance in early stages. Mucosal infection by the human papillomavirus (HPV) is responsible for a growing number of malignancies, particularly cervical cancer and oropharyngeal carcinomas. In addition, Candida albicans (C. albicans), which is the principal fungi involved in the oral cancer development, may induce carcinogenesis through several mechanisms, mainly promoting inflammation. Medical knowledge and research on adolescent/pediatric patients' management and prevention are in continuous evolution. Besides, microbiota can play an important role in maintaining oral health and therefore all human health. The aim of this review is to evaluate epidemiological and pathophysiological characteristics of the several biochemical pathways involved during HPV and C. albicans infections in pediatric dentistry.

Stem Cells: A Historical Review about Biological, Religious, and Ethical Issues.

Stem cells can be used to replace damaged cells or regenerate organs and have broadened our knowledge of the development and progression of certain diseases. Despite significant advances in understanding stem cell biology, several problems limit their use. These problems are related not only to the growth of tumors in animal models and their rejection in transplant cases but also to ethical and social issues about the use of embryonic cells. The ethical-scientific debate on this type of cells has taken on great interest both for their application in regenerative medicine and for the potential possibilities in the field of cell and gene therapy. Different points of view often have the expression of a perception that depends on scientific goals or opportunities or on religious traditions and beliefs. Therefore, as the questions and doubts about when life begins, so do the answers for the use of these cells as therapy or otherwise. So, in addition to the origin of stem cells, there are currently some social bioethical (such as political and legislative issues) and religious dilemmas. The purpose of the study is aimed at being a narrative on the history of stem cells and the evolution of their use to date, as well as to clarify the bioethical position of the various religions today in comparison with the social ones regarding the research and use of embryonic and adult ones. Hence, their biological hypostasis regarding the concepts of "conception" and "fertilization" and their development and therapeutic use compared to those of the main theological doctrines.

Focus on HPV Infection and the Molecular Mechanisms of Oral Carcinogenesis.

This study is focused on the epidemiological characteristics and biomolecular mechanisms that lead to the development of precancerous and cancerous conditions of oral lesions related to Human Papilloma Virus (HPV) infections. Current evidence from the literature demonstrates the role of HPV in potentially malignant oral disorders. Therefore, the underlying biomolecular processes can give arise, or contribute to, benign lesions as well as to oral carcinogenesis.