Fusobacterium nucleatum and alteration of the oral microbiome: from pregnancy to SARS-COV-2 infection

OBJECTIVE

The human being has evolved in close symbiosis with its own ecological community of commensal, symbiotic and pathogenic bacteria. After the intestinal microbiome, that of the oral cavity is the largest and most diversified. Its importance is reflected not only in local and systemic diseases, but also in pregnancy since it would seem to influence the placental microbiome.

MATERIALS AND METHODS

This is a literature review of articles published in PubMed about Fusobacterium Nucleatum and both its implications with systemic and oral health, adverse pregnancy outcomes, flavors perception and its interference in the oral-nasal mucosal immunity.

RESULTS

It is in maintaining the microbiome's homeostasis that the Fusobacterium nucleatum, an opportunistic periodontal pathogen of the oral cavity, plays a crucial role both as a bridge microorganism of the tongue biofilm, and in maintaining the balance between the different species in the oral-nasal mucosal immunity also by taste receptors interaction. It is also involved in the flavor perception and its detection in the oral microbiome of children from the first days of life suggests a possible physiological role. However, the dysbiosis can determine its pathogenicity with local and systemic consequences, including the pathogenesis of respiratory infections.

CONCLUSIONS

It is interesting to evaluate its possible correlation with Sars-CoV-2 and the consequences on the microflora of the oral cavity, both to promote a possible broad-spectrum preventive action, in favor of all subjects for whom, by promoting the eubiosis of the oral microbiome, a defensive action could be envisaged by the commensals themselves but, above all, for patients with specific comorbidities and therefore already prone to oral dysbiosis.

Early combination treatment with existing HIV antivirals: an effective treatment for COVID-19?

OBJECTIVE

Since no effective therapy exists, we aimed to test existing HIV antivirals for combination treatment of Coronavirus disease 19 (COVID-19).

MATERIALS AND METHODS

The crystal structures of SARS-CoV-2 main protein (Mpro) (PDB ID: 6Y2F) and SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) (PDB ID: 7BV2) both available from Protein Data Bank were used in the study. Automated Docking by using blind and standard method both on Mpro and RdRp bound to the modified template-primer RNA was performed with AutoDock 4.2.6 program suite. Lamarckian genetic algorithm (LGA) was used for structures docking. All inhibitors were docked with all bonds completely free to rotate.

RESULTS

Our molecular docking findings suggest that lopinavir, ritonavir, darunavir, and atazanavir activated interactions with the key binding sites of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) protease with a better inhibition constant (Ki) for lopinavir, ritonavir, and darunavir. Furthermore, we evidenced the ability of remdesivir, tenofovir, emtricitabine, and lamivudine to be incorporated in SARS-CoV-2 RdRp in the same protein pocket where poses the corresponding natural nucleoside substrates with comparable Ki and activating similar interactions. In principle, the four antiviral nucleotides might be used effectively against SARS-CoV-2.

CONCLUSIONS

The combination of a protease inhibitor and two nucleoside analogues, drugs widely used to treat HIV infection, could be evaluated in clinical trials for the treatment of COVID-19.

Sportomics: metabolomics applied to sports. The new revolution?

Sportomics is the application of metabolomics in sports to investigate the metabolic effects of physical exercise on individuals, whether they are professional athletes or not. Metabolomics is one of the "omics" sciences that provide a picture of the metabolic state of a person in physiological or pathological conditions. This is achieved through the analysis of metabolites present in a biological fluid, such as saliva, blood, feces, and urine. The authors revised the recent literature concerning this topic and discussed the useful information that sportomics can provide and the limits of the current experimental settings. Furthermore, in the future, sportomics analyses could be used to prevent and manage injuries as it would be known in advance if an athlete is more prone to experience muscular damage or fatigue. Following more trials, it would also be possible to set the best diet and training programs to get the best performances out of the athletes. Moreover, based on their metabolic profiles, both adults and children could choose tailored physical training in order to preserve and improve their health.

Complex trauma, PTSD and complex PTSD in African refugees

Background: The introduction of the diagnosis of complex posttraumatic stress disorder (CPTSD) by ICD-11 is a turning point in the field of traumatic stress studies. It's therefore important to examine the validity of CPTSD in refugee groups exposed to complex trauma (CT) defined as a repeated, prolonged, interpersonal traumatic event. Objective: The objective of this study was to compare DSM-5 and ICD-11 post-traumatic stress disorder diagnoses and to evaluate the discriminant validity of ICD-11 PTSD and CPTSD constructs in a sample of treatment-seeking refugees living in Italy. Method: The study sample included 120 treatment-seeking African refugees living in Italy. All participants were survivors of at least one CT. PTSD and CPTSD diagnoses were assessed according to both DSM-5 and ICD-11 criteria. Results: Findings revealed that 79% of the participants met the DSM-5 criteria for PTSD, 38% for ICD-11 PTSD and 30% for ICD-11 CPTSD. Generally, ICD-11 CPTSD items evidenced strong sensitivity and negative predictive power, low specificity and positive predictive power. Latent class analysis results identified two distinct groups: (1) a PTSD class, (2) a CPTSD class. None of the demographic and trauma-related variables analysed was significantly associated with diagnostic group. On the other hand, the months spent in Italy were significantly associated with PCL-5 score. Conclusions: Findings extend the current evidence base to support the discriminant validity of PTSD and CPTSD amongst refugees exposed to torture and other gross violations of human rights. The results suggest also that, in the post-traumatic phase, the time spent in a 'safe place' condition contributes to improve the severity of post-traumatic symptomatology, but neither this variable nor other socio-demographic factors seem to contribute to the emergence of complex PTSD. Further investigations are needed to clarify which specific vulnerability factors influence the development of PTSD or CPTSD in refugees exposed to complex trauma.

Myoinositol: a new marker of intrauterine growth restriction?

Inositol is a cyclic sugar alcohol which occurs naturally in a variety of stereoisomers, the most common of which is myo-inositol. Inositol phosphoglycan molecules have been isolated from mammalian tissues and are a major component of the intracellular mediators of insulin action. The fetus with intrauterine growth retardation (IUGR) activates a series of adaptive mechanisms to increase the chances for survival, such as a saving of glucose to ensure nutrition of the vital organs, with a consequent reduction in insulin secretion. It can be hypothesized that the reduced production of fetal insulin leads to an excretion of inositol from the intracellular to the extracellular compartment, with a consequent increase of the metabolite in plasma and urine and a decrease inside the cells. Recently, reports suggesting that the increase in extracellular myo-inositol may be a valid marker of an altered glucose metabolism during fetal development in IUGR have been published.

Serratia marcescens infections and outbreaks in neonatal intensive care units

Serratia marcescens is an important cause of hospital-acquired infections, especially in neonatal intensive care units (NICUs). This review analyzes clinical signs, risk factors, biotyping and sources of infection in newborns exhibited by this bacteria as well as the therapy which is commonly used and management. This review examines the reported cases of outbreaks of S. marcescens in NICUs published in pubmed over the last 10 years (key words: Serratia marcescens infections, outbreaks, Neonatal intensive Care Units). This report highlights the different prevention and control strategies employed in order to eradicate Serratia outbreaks in NICUs, including all healthcare procedures such as hand washing, introduction of alcohol-based antiseptic gel, enhanced cleaning and disinfection of medical equipment and wards, use of single-patient medical instruments, cohorting of colonized and infected infants, periodic screening cultures, earliest discharge of the infants.

Ultrasound in developmental dysplasia of the hip: A screening study in Sardinian newborns

INTRODUCTION

Developmental dysplasia of the hip (DDH) is the most frequent inborn deformity of the locomotor apparatus. Ultrasound screening is frequently used to identify DDH in view of the brevity of the preclinical period during which diagnosis is possible. Appropriate therapeutic intervention during this period can positively affects the evolution of the disorder.

METHODS

An unselected population of 1158 Sardinian neonates underwent ultrasound examinations of both hips, and findings were classified according to the method described by Graf. Patients were assessed by means of retrospective analysis to reveal cases of congenital dislocation of the hip joint. All cases were classified and treatment outcomes determined.

RESULTS

A total of 145 hips requiring treatment were observed in 122 children. Hip dysplasia and/or dislocation were diagnosed between the ages of 14 days and 3 months. One month after diagnosis ultrasound findings were normal in 94% of the infants with at least one hip classified as type 2a. The remaining 6% were classified as types 2b, 2c, D, and 3. All were treated with abduction splints, and normal hip development was observed after one or two months of treatment. Type 4 hips were referred to an orthopedic surgeon for specialist treatment.

CONCLUSIONS

When performed by skilled operators, ultrasonographic techniques are of considerable value in prescribing treatment for DDH. The satisfactory prognosis associated with early treatment of severe congenital dislocation of the hip joint underlines the advisability of scheduling routine hip screening programs to ensure early diagnosis and effective treatment of the disorder.

Serum levels of leptin and proinflammatory cytokines in patients with advanced-stage cancer at different sites

Leptin is a recently identified hormone produced by the adipocyte ob gene which acts as a negative feedback signal critical to the normal control of food intake and body weight. A number of proinflammatory cytokines, such as interleukin (IL) 1alpha, IL-6, tumor necrosis factor (TNF) alpha and interferon (IFN) gamma, have been proposed as mediators of cancer cachexia. These data suggest that abnormalities in leptin production/release or in its feedback mechanism play a role in cancer patients. To elucidate this we studied the relationship between total serum leptin and serum cytokines IL-1alpha, IL-6, TNFalpha as well as the production of leptin and cytokines by peripheral blood mononuclear cells (PBMC) isolated from cancer patients. Sixteen advanced cancer patients (mainly stage IV) with tumors at different sites were included in the study. The serum levels of leptin in cancer patients were significantly lower than those of healthy individuals at all times (7 a.m., noon, 3 p.m.). No significant differences were found in circadian rhythm between patients and controls. Serum levels of IL-1alpha, IL-6, and TNFalpha were significantly higher in cancer patients than in healthy individuals. An inverse correlation between serum levels of leptin and IL-6 was found in cancer patients. The production in culture of leptin by unstimulated PBMCs and those stimulated by phytohemagglutinin M or by phorbol myristate acetate isolated from cancer patients was very low; no differences were observed in comparison with leptin production by PBMCs from healthy individuals.

Relationship between Helicobacter pylori infection and gastric follicular hyperplasia. A retrospective study

BACKGROUND

The occurrence of lymphoid follicles in the gastric mucosa was recently considered to be acquired in respose to infection by Helicobacter pylori.

METHODS

In order to investigate whether there is any correlation between follicular hyperplasia and Helicobacter pylori colonization, a morphological study was performed in antral biopsy specimens from 267 patients with H. pylori-associated gastritis, and from 312 subjects with histological evidence of chronic gastritis, but without H. pylori colonization.

RESULTS

Follicular hyperplasia was observed in 33 (12.3%) specimens with H. pylori-associated gastritis, and in 56 (9%) samples from non-infected group (p=ns). In both H. pylori-positive and H. pylori-negative specimens lymphoid follicular hyperplasia showed a significant correlation with the degree of the gastritis. In these two groups the prevalence of follicular hyperplasia was also significantly higher in the elderly.

CONCLUSIONS

On the basis of these results, we were unable to find any significant correlation between H. pylori infection and occurrence of lymphoid follicular hyperplasia. The appearance of organized follicular structures in the gastric mucosa seems to be acquired in response to multiple events, and not exclusively in consequence of the colonization by Helicobacter pylori.

A retrospective study on the incidence of lymphocytic gastritis in patients with Helicobacter pylori infection

To investigate the relationship between lymphocytic gastritis and H. pylori infection, antral biopsy specimens from 162 patients with histological evidence of H. pylori infection, and from 177 subjects without colonization were retrospectively examined. Among patients with antral colonization, lymphocytic gastritis was identified in 8 cases (4.9%). Lymphocytic gastritis was not detected in specimens without H. pylori infection. Quantitation of the epithelial lymphocytic infiltration was carried out in all specimens and showed that cases with lymphocytic gastritis had a mean of 35.3 lymphocytes per 100 epithelial cells, compared with a mean of 2.6 and 2.4 respectively in chronic gastritis and normal mucosa. Among the 331 patients without lymphocytic gastritis, specimens colonized by H. pylori had a mean of epithelial lymphocyte counts significantly higher than those observed in both chronic gastritis and normal mucosa. These findings show a positive correlation between antral colonization by H. pylori and occurrence of lymphocytic gastritis, and suggest that the bacteria may have an important role in the induction of such particular form of antral inflammation.

Helicobacter pylori in Barrett's esophagus and in normal or inflamed esophageal mucosa: a retrospective study

To investigate on the presence and significance of Helicobacter pylori (Hp) in Barrett's mucosa, esophageal biopsy specimens from 34 patients with columnar-lined epithelium were retrospectively examined. The incidence of colonization was compared with that observed in a control group of 76 subjects with normal esophageal mucosa or moderate esophagitis. Three of the 34 Barrett's specimens were Hp-positive and only 1 of these showed evidence of inflamed mucosa (p = NS). We do not find in this study any evidence to support the existence of association between Hp and Barrett's esophagus or esophageal inflammation. The presence of Hp in antral mucosa of all positive cases suggest the possibility that esophageal colonisation might merely be a consequence of reflux from the gastric antrum.

EPR investigation of the oxovanadium(IV) complexes formed by the tripeptide glutathione and some related ligands in aqueous solution

Complex formation between oxovanadium(IV) and glutathione (gamma-L-glutamyl-L-cysteinylglycine, GSH) was investigated in aqueous solution by EPR and electron absorption spectroscopy to identify the complexed species that were reported to form upon reduction of exogenous vanadium(V) in cellular systems. The complexing behavior of the related ligands glycine, N-acetyl-glycine, 3-mercaptopropionic acid, cysteamine, L-cysteine, N-acetyl-L-cysteine, N-acetyl-cysteamine, and oxidized glutathione (GSSG) was also examined in order to have suitable reference models. The results are compared with those reported previously.

Effect of Helicobacter pylori colonization on quantitative distribution of antral G-cells in apparently healthy subjects and in duodenal ulcer patients. A morphometric study

To investigate whether antral colonization by Helicobacter pylori (Hp) modifies gastrin-cell population, the number of G-cells was evaluated in antral biopsy specimens from 22 apparently healthy subjects and from 48 duodenal ulcer patients using a morphometric method. The level of serum immunoreactive gastrin in a sample of fasting serum obtained at the time of biopsy was also measured. In healthy subjects the G-cell count (evaluated according to G/I index) and the serum gastrin levels were not significantly different than those found in duodenal ulcer patients. When the antral colonization by Hp was assessed, we found that, both controls and duodenal ulcer Hp-positive patients had a mean G-cell count and fasting serum gastrin levels not significantly higher than in patients without Hp.

Helicobacter pylori and intestinal metaplasia in antral mucosa. A study on their correlation

To investigate the possible relation between Helicobacter pylori (HP) colonization and incidence of intestinal metaplasia (IM), antral biopsy specimens from a total of 263 subjects (167 had chronic gastritis, 12 gastric cancer, and 84 no histological changes) were examined. IM was observed in 27.7% of the HP positive specimens and in 18.3% of the HP negative biopsies (p = NS). Histochemical characterization of mucins showed that the percentage of HP colonization was not significantly different within various subtypes of IM. We do not find in this study any evidence to support the existence of a pathogenetic role of HP on the morphogenesis of IM in antral mucosa.

[The relationship between dietary intake of vitamin A and risk of gastrointestinal neoplasia]

A study on dietary intake of retinol and beta-carotene was conducted in 51 patients affected by gastric (23 cases) and colorectal (28 cases) carcinoma, considering the period preceding the onset of their illness. In all patients were measured serum retinol levels. The data were compared with those in 44 control subjects. Mean values of retinol and beta-carotene intake in the two groups showed not significant differences. The mean serum levels of retinol were similar in controls and in cancer patients (68.1 and 66.8 micrograms/dl, respectively). Our data fail to confirm previous observations about relationship between alimentary intake of retinol and beta-carotene and risk of gastrointestinal cancer.

Oxovanadium(IV) complex formation by simple sugars in aqueous solution

The binding of oxovanadium(IV) to simple sugars in neutral or basic aqueous solution, as studied by EPR and electronic absorption spectroscopy, is reported. The complexation is favored in basic media and involves the coordination of the metal ion to couples of adjacent deprotonated hydroxyls of the sugar molecule. However, only the ligands provided with cis couples can adopt this chelating ligand behavior. The ability of the cis hydroxyl couples to yield chelated complexes has been related to the structural rearrangement (decrease of the O-C-C-O torsion angle in the five-membered chelated ring) needed to permit the oxovanadium(IV) coordination by the sugar molecule.

[Tissue carcinoembryonic antigen in normal conditions and neoplastic pathology of the colorectum]

Using an immunohistochemical method, carcinoembryonic antigen (CEA) was evaluated in bioptic specimens from 12 colorectal carcinomas, 32 neoplastic polyps and from 12 preparations of normal rectocolonic mucosa. CEA was demonstrated in 7/12 samples of normal mucosa, always localized on the apical pole of the columnar cells. In carcinomatous specimens CEA was found in 11/12 biopsies and showed a localization predominantly intracytoplasmatic or in the surrounding stroma. In 8/12 tumor specimens tested, the histologically normal mucosa bordering the carcinoma exhibited a slight staining for CEA on the apical surface of the glandular cells. Specimens from 27/32 polyps biopsied appeared to contain CEA on the apical pole of the glandular cells. These results confirm that CEA is a normal constituent of the human adult rectocolonic mucosa; the difference in CEA content between benign and malignant mucosa is very likely quantitative rather than qualitative. No indications on the prognosis of the polyps could be obtained from this study.

Intestinal metaplasia of the gastric mucosa: a study of its incidence in various disease states

The incidence of intestinal metaplasia (IM) was studied in 159 specimens from gastric mucosa. Rare in histologically normal specimens (4%), the IM showed the highest incidence in patients with gastric carcinoma (75%). Intermediate values were observed in chronic atrophic gastritis (25%) and peptic ulcer (21%). Histochemical data shows that type complete-IM was most common in benign conditions; type incomplete-IM and particularly subtype secreting sulphomucins revealed a higher frequence in the mucosa bordering carcinomas.

Mucin histochemistry in Barrett's esophagus

Specimens from twelve patients with Barrett's esophagus and four additional cases of esophageal carcinoma who had Barrett's epithelium were histologically and by mucin histochemistry examined. Specialized epithelium was observed in 10/12 non cancerous patients. In 9 of these either gastric-fundic or junctional epithelium were seen. All patients with carcinoma had evidence of specialized epithelium. Sulphated mucins were preponderant in biopsies from 7 of the 9 patients with dysplasia either alone or associated with carcinoma. In all 5 specimens with specialized epithelium but without dysplasia or carcinoma, sialomucins were predominant.

[The role of Campylobacter pylori in gastroduodenal pathology]

Biopsy specimens from the gastric antral mucosa of 194 patients with upper gastrointestinal symptoms were studied with the Warthin-Starry silver stain to demonstrate the presence of Campylobacter Pylori (CP). Of these patients, 44 had peptic ulcer visible on endoscopic investigation. Spiral bacteria were detected in 70 out of 75 specimens with histologically active gastritis (93%), in 34 of 54 specimens with inactive form of gastritis (63%) and in 26 of 65 specimens without morphological changes (40%). Of 44 patients found to have gastric or duodenal ulcers, 33 also had bacteria. No significant differences between patients with endoscopically visible peptic ulcer and those without ulcer were seen. Our results indicate a close relationship between the active form of chronic gastritis and Campylobacter; however they do not show a definite association with peptic ulcer.