Vitamin D: a steroid hormone with progesterone-like activity

OBJECTIVE

This review is aimed at demonstrating the progesterone-like activity exerted by the active form of vitamin D, or calcitriol (1,25(OH)2D). To achieve this outcome, we compared the effects in vivo and in vitro exerted by progesterone and vitamin D, with a special focus on the female reproductive system and pregnancy.

MATERIALS AND METHODS

This is a literature review of the most important articles published in English on vitamin D as a hormone, mainly found by MEDLINE. Furthermore, a section of our review contains some unpublished data, concerning the analysis in silico of the similarities between the steric structure of progesterone and calcitriol, based on the availability of the experimental structures of progesterone and vitamin D3 receptors in complex with their physiological ligands in the RCSB Protein Data Bank.

RESULTS

Vitamin D was shown to exert many physiological activities during the very early stages of gestation in perfect synchrony with progesterone. Both the molecules mutually help and reinforce the activity exerted by each one. A little bit later than progesterone is released, vitamin D secretion rises, but only if pregnancy occurs. Calcitriol contributes to prepare the endometrium to be receptive. Moreover, it supports the implantation process and the course of pregnancy through different but similar pathways to those used by progesterone, giving rise to a significant synergy of action. It is increasingly evident that vitamin D gives an essential support from the luteal phase onwards.

CONCLUSIONS

Based on the evidence displayed in this review we may define appropriately vitamin D as a steroid hormone with progesterone-like activity.

Predictors of Hepatitis B Surface Antigen Titers two decades after vaccination in a cohort of students and post-graduates of the Medical School at the University of Palermo, Italy

Introduction and objective. The introduction of a vaccine against hepatitis B virus (HBV) for newborn babies in Italy in 1991, extended to 12-year-old children for the first 12 years of application, has been a major achievement in terms of the prevention of HBV infection. The objective of this study was to analyse the long-term immunogenicity and effectiveness of HBV vaccination among healthcare students with different working seniorities. Materials and method. A cross-sectional observational study of undergraduate and postgraduate students attending the Medical School of the University of Palermo was conducted from January 2014 - July 2016. HBV serum markers were performed with commercial chemiluminescence assays. Categorical variables were analyzed using the chi-square test (Mantel-Haenszel), whereas means were compared by using the Student's t test. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were also calculated by a multivariable logistic regression, using a model constructed to examine predictors of anti-HBs titer above 10 mIU/mL, assumed as protective. Results. Of the 2,114 subjects evaluated - all vaccinated at infancy or at the age of 12 years and were HBsAg/anti-HBc negative - 806 (38.1%) had an anti-HBs titre <10 IU/L. The latter were younger, more likely to be attending a healthcare profession school (i.e., nursing and midwifery), than a medical postgraduate level school, and more likely to have been vaccinated in infancy (p <0.001, 95% CI 2.63-5.26, adjusted OR 3.70). Conclusion. The results of the study suggest that assessment of HBV serum markers in workers potentially exposed to hospital infections is useful for identifying small numbers of unvaccinated subjects, or vaccinated subjects with low antibody titre, all of whom should be referred to a booster series of vaccinations.

N-acetylcysteine as powerful molecule to destroy bacterial biofilms. A systematic review

OBJECTIVE

Biofilms are microbial communities consisting of bacteria, extremely capable to self-reproduce on biological surfaces, causing infections. Frequently, these biofilms are resistant to classical antibacterial treatments and host immune response. Thus, new adjuvant molecules are mandatory in clinical practice. N-acetylcysteine (NAC), a precursor to the antioxidant glutathione, has been investigated for its effectiveness both in inhibiting biofilm formation and in destroying developed biofilms. The aim of our study was to conduct a systematic literature review of clinical trials involving NAC as adjuvant treatment to eradicate pre-formed mature biofilms and to inhibit new biofilm production.

MATERIALS AND METHODS

A careful analysis of the Medline was conducted and eight studies were selected according to the following criteria: site of infection, kind of bacteria, design of the research, dose of the treatment, administration, biological effects and results. We fixed an arbitrary scale of scores from 0 (lowest score) to 5 (highest score) for each criterion and a threshold value of 3.

RESULTS

The studies analyzed, with score over 3, suggested a potential role for NAC as adjuvant molecule in the treatment of bacterial biofilms, with an excellent safety and efficacy profile. NAC, in combination with different antibiotics, significantly promoted their permeability to the deepest layers of the biofilm, overcoming the problem of the resistance to the classic antibacterial therapeutic approach.

CONCLUSIONS

Overall, these results are encouraging to a more widespread clinical use of NAC, as adjuvant therapy for microbial infections followed by biofilm settle, which may occur in several body districts, such as the vaginal cavity.

Analysis of early strains of the norovirus pandemic variant GII.4 Sydney 2012 identifies mutations in adaptive sites of the capsid protein

Global surveillance for norovirus identified in 2012 the emergence of a novel pandemic GII.4 variant, termed Sydney 2012. In Italy, the novel pandemic variant was identified as early as November 2011 but became predominant only in the winter season 2012-2013. Upon sequencing and comparison with strains of global origin, the early Sydney 2012 strains were found to differ from those spreading in 2012-2013 in the capsid (ORF2) putative epitopes B, C and D, segregating into a distinct phylogenetic clade. At least three residues (333, 340 and 393, in epitopes B, C and D, respectively) of the VP1 varied among Sydney 2012 strains of different clades. These findings suggest that the spread of the pandemic variant in Italy during the winter season 2012-2013 was due to the introduction of strains distinct from those circulating at low frequency in the former winter season and that similar strains were also circulating elsewhere worldwide.

Peripheral neuropathy in obstetrics: efficacy and safety of α-lipoic acid supplementation

OBJECTIVE

Neuropathic pain during pregnancy is a common condition due to the physical changes and compression around pregnancy and childbirth that make pregnant women more prone to develop several medical conditions such as carpal tunnel syndrome, sciatica, meralgia paraesthetica and other nerve entrapment syndromes. Most of the treatments usually performed to counteract neuropathic pain are contraindicated in pregnancy so that, the management of these highly invalidating conditions remains an issue in the clinical practice. We aimed to review the efficacy and safety of alpha lipoic acid supplementation in the treatment of neuropathic pain.

DISCUSSION

Lipoic acid is a co-factor essential in the regulation of mitochondrial energy. It has been demonstrated that lipoic acid supplementation is involved in several biochemical processes and actions, exerting important antioxidant and anti-inflammatory activity and significantly improving pain and paraesthesia in patients with sciatica, carpal tunnel syndrome and diabetic neuropathy.

CONCLUSIONS

Efficacy of lipoic acid is combined with a high safety profile, making this molecule a novel candidate for the management of several diseases. Data reported so far are promising and dietary supplementation with lipoic acid seems a useful tool to contrast neuropathic pain during pregnancy.

A feline rotavirus G3P[9] carries traces of multiple reassortment events and resembles rare human G3P[9] rotaviruses

The full-length genome sequence of a feline G3P[9] rotavirus (RV) strain, BA222, identified from the intestinal content of an adult cat, was determined. Strain BA222 possessed a G3-P[9]-I2-R2-C2-M2-A3-N1-T3-E2-H3 genomic constellation, differing substantially from other feline RVs. Phylogenetic analyses of each genome segment revealed common origins with selected animal and zoonotic human RVs, notably with rare multi-reassortant human G3P[9] RVs (Ita/PAI58/96 and Ita/PAH136/96). Altogether, the findings suggest that feline RVs are genetically diverse and that human RVs may occasionally originate either directly or indirectly (via reassortment) from feline RVs.

Diversity of human rotaviruses detected in Sicily, Italy, over a 5-year period (2001-2005)

Rotavirus infection was detected in 39.9% of 1030 children hospitalized with gastroenteritis in Palermo, Italy, in the period 2001-2005. Rotavirus strains belonging to G1, G4 and G9 types were continually detected, with G1 being the most common type in 2001, 2002 and 2004. A G4 epidemic occurred in 2003, while G9 was predominant in 2005. G2 strains displayed a low prevalence, except in 2003. G3 rotaviruses accounted for 2.7-17% of the gastroenteritis episodes in 2002-2005. The P-type of a subset of 166 strains confirmed the circulation of the usual G/P combinations, but single G1P[6], G9P[9] and G6P[9] strains were also found.

Viral gastroenteritis in children hospitalised in Sicily, Italy

The aim of the present study was to describe the epidemiologic and clinical characteristics of acute viral gastroenteritis in hospitalised Italian children. A total of 215 stool specimens were collected from January to December 2003 from patients hospitalised in Palermo for acute diarrhoea. Samples were tested for group A rotavirus, astrovirus, adenovirus, norovirus, enteropathogenic bacteria, and parasites. Rotaviruses, mostly belonging to types G1-G4, were detected in 25.1% of samples, astrovirus in 7%, adenovirus in 6%, norovirus in 18.6%, and bacterial agents in 17.2%. No parasitic infections were diagnosed. Mixed infections represented 9.8% of all cases. The mean and median ages of children with rotavirus gastroenteritis were lower than those of children with other viruses (p = 0.029), with the highest median ages being found in astrovirus-infected patients. Vomiting and dehydration were more frequent among patients with viral infection (p < 0.01), and the severity score was significantly higher for children infected with astrovirus or group A rotavirus (p = 0.008). Rotavirus was the leading cause of prolonged hospitalisation (p = 0.005). In conclusion, viruses were confirmed in Italy as the most common cause of severe enteric illness in childhood, with rotavirus types G1-G4, which correspond to those included in the rotavirus vaccines being developed, playing the main role. Routine testing should be introduced for noroviruses, since they seem to represent an important cause of sporadic paediatric gastroenteritis.

Genetic variability among serotype G4 Italian human rotaviruses

A total of 254 serotype GH rotavirus strains were detected in Palermo, Italy, from 1985 to 2003. Out of 38 serotype G4 strains selected for genetic analysis, 14 were recognized by genotyping as type G9. Strains confirmed to belong to the G4 type showed temporal patterns of genetic evolution in their VP7 and VP4 gene sequences, and the latest Italian G4 strains were distantly related to the reference vaccinal ST3 strain.

Molecular epidemiology of astrovirus infection in Italian children with gastroenteritis

Abstract A 1-year study involving 157 gastroenteritis samples was conducted to investigate the role of human astrovirus (HAstV) as a cause of gastroenteritis in Italian children aged < 2 years. The overall incidence of HAstV was 3.1%. Most cases occurred between March and May, and four of the five isolates were of the HAstV-1 type, the other being HAstV-3. Analysis of genetic variability showed that the three HAstV-1 isolates collected in 2000 clustered together, but separately from the 1999 isolate. The results indicated that HAstV should be considered as a potential diarrhoeal pathogen in Italian children.

Molecular characterization of the genotype G9 human rotavirus strains recovered in Palermo, Italy, during the winter of 1999-2000

Among the known human rotavirus serotypes, types G1-G4 are ubiquitous and account for >80% of global human rotavirus strains. Since 1994 an increase in reports of G9 serotype isolates has been observed in both developed and developing countries. In the winter season of 1999-2000 we detected the appearance of G9 rotavirus in Palermo, Italy, accounting for 19% of all rotaviruses circulating in our geographical area. Some of these Italian G9 isolates have been submitted to partial sequencing of their VP7 gene. All of them showed complete nucleotide identity suggesting a clonal origin. The Italian VP7 sequences were found to be very closely related to that of other G9 strains recently isolated in Europe, America, Africa and Asia. Our results confirm that G9 strains circulating worldwide since 1994 are closely related genetically in their VP7 genes.

Human cytomegalovirus glycoprotein B genotypes in immunocompetent, immunocompromised, and congenitally infected Italian populations

Human cytomegalovirus (HCMV) strains, obtained from immunocompetent and immunocompromised Italian hosts, were typed with glycoprotein B (gB) gene restriction analysis. A predominant circulation of HCMV strains with gB type 2 and 3 was detected in both the immunocompetent host with a primary HCMV infection and the immunocompromised host with or without HCMV disease. No association between gB types and subjects with different risks of developing HCMV disease was found. All four gB genotypes were capable of causing congenital infection in Italian babies, with gB type 1 accounting for 50% of the strains examined in symptomatic infants and a remarkable incidence of gB type 4 viruses.