Mario Salmeri

Bifidobacterium combined with fructo-oligosaccharide versus lactulose in the treatment of patients with hepatic encephalopathy

Background Hepatic encephalopathy (HE) is a reversible neuropsychiatric syndrome in patients with liver disease. It was suggested that Bifidobacterium+fructo-oligosaccharides (FOS) may decrease blood and brain ammonia levels. Aim The study was conducted to compare the efficacy of Bifidobacterium+FOS and lactulose in patients with HE. Methods One hundred and twenty-five patients (35 hepatitis B virus infected, 70 hepatitis C virus infected and 20 cryptogenetic cirrhosis) were enrolled in the study. Patients were randomized either to a treatment for 60 days with Bifidobacterium and FOS (group A) or into-group receiving lactulose (group B) in double-blind. Results After 30 days of the study period, the Bifidobacterium+FOS-treated patients compared with lactulose-treated patients showed a significant decrease of Trail Making Test B (TMT B) (P<0.005), and a significant increase of Symbol Digit Modalities Test (P<0.001) and Block Design Test (P<0.001). After 60 days of the study period, the Bifidobacterium+FOS-treated patients compared with lactulose-treated patients showed a significant decrease of NH4 fasting HE1 (P<0.001), TMT A (P<0.05), TMT B (P<0.001), and a significant increase of Symbol Digit Modalities Test (P<0.001) and Block Design Test (P<0.001). Conclusion The treatment with Bifidobacterium+FOS is an alternative to the use of lactulose in patients with cirrhosis, for its usefulness in reducing blood ammonia levels and improvement of psychometric tests.

Probiotics in the gastrointestinal diseases of the elderly

Changes of the gut microflora in elderly appear to involve a reduction in numbers of healthy bacteria (lactobacilli and bifidobacteria) and an increase in numbers of potentially pathogenic species. These changes are generally described as gastrointestinal disorders and infections. This review analyses benefits of probiotics in old people, with particular interesting for the latest researches relevant to elderly people, e.g. trials examining enteric infections, antibiotic-associated diarrhea and Clostridium difficile associated diarrhea, functional bowel problems (constipation and irritable bowel syndrome), inflammatory bowel diseases, stimulation of the immune system and prevention of cancer. A growing number of researches indicates that some probiotic strains may help to maintain the health in old people, suggesting both health and cost-saving benefits in offering fermented dairy products. These benefits include: establishment of balanced intestinal microflora; improving colonization resistance and or prevention of diarrhea; reduction of fecal enzymes; reduction of serum cholesterol; reduction of potential mutagenes; reduction of lactose intolerance; synthesis of vitamins; predigestion of proteins.

Microbiological investigation in male infertility: a practical overview

The roles of inflammation and/or infection of the male accessory sex glands are very important for the potential effects that these conditions may have on male fertility. The clinical andrologist should be aware of the pathophysiological role of the main determinants of sperm damage when these conditions occur, in particular, seminal leukocytes, oxidative stress and cytokines. In addition, it is important to have a good knowledge of the methodologies to be used in clinical practice. This article summarizes the methods used to look for and to identify the micro-organisms responsible for male urogenital tract infections. These include sperm culture, urine culture, urethral swabbing, the Meares-Stamey test and balanopreputial swabbing. Finally, we discuss the role of human papilloma virus infection in male infertility.

Prevalence of Ureaplasma urealyticum and Mycoplasma hominis infection in unselected infertile men

Abstract In this study, we investigated the prevalence of Ureaplasma urealyticum and Mycoplasma hominis infection among 250 unselected infertile men, the presence of urogenital symptoms in infected men and the effects of these microorganisms on the conventional sperm parameters. Urethral samples were obtained using a swab inserted 3–4 cm into the urethral meatus. Ureaplasma urealyticum and Mycoplasma hominis were detected by the kit Mycofast R evolution 3 Elitech Microbiology (Elitech Microbiology, Signes, France). Ureaplasma urealyticum was detected in 15·6% of the cases and Mycoplasma hominis in 3·6%. One patients had a co-infection with both pathogens. About 41% of the infertile patients with mycoplasma infection had urogenital symptoms. A lower number of patients with mycoplasma infection had normal sperm parameters compared with non-infected infertile men, but this frequency showed only a trend compared to non-infected patients (Chi-square = 3·61; P = 0·057), and a significantly higher percentage of patients with oligo-astheno-teratozoospermia (Chi-square = 127·3; P<0·0001), or asthenozoospermia alone (Chi-square = 5·74; P<0·05) compared to non-infected infertile patients. In conclusion, this study showed an elevated prevalence of ureaplasma urealyticum and mycoplasma hominis infection in unselected men attending an infertility outpatient clinic and that the presence of these microorganisms is associated with a higher percentage of patients with abnormal sperm parameters.

An in vitro retinoblastoma human triple culture model of angiogenesis: a modulatory effect of TGF-β.

Retinoblastoma is the most common intraocular tumour in children. In view of understanding the molecular mechanisms through which angiogenic switch on happens in the early phases of reciprocal interaction between tumour and cells constituting retinal microvessel, Transwell co-cultures constituted by human retinal endothelial cells (HREC), pericytes (HRPC), and human retinoblastoma cell line Y-79 were performed. Y-79 enhanced HREC proliferation, reduced by the introduction of HRPC in triple culture. In HREC/HRPC cultures, TGF-β in media increased, decreasing in triple cultures. High VEGF levels in triple cultures witnessed the establishment of a strongly in vitro angiogenic environment. Y-79 induced in HREC an increase in c- and iPLA2, phospho-cPLA2, inducible COX-2 protein expressions, PLA2 activities and prostaglandin E2 (PGE2) release. These effects were attenuated when HRPC were introduced in triple culture. Moreover, antibody silencing of TGF-β demonstrated a strong correlation between the signalling pathway triggered by TGF-β of pericytal origin and the phospholipase activation and the modulation of PGE2 release. Inhibiting VEGFA effect, the HRPC loss in triple culture decreased, showing its modulatory effect on their survival. Relying on the data here presented, sustaining the pericytal survival in a tumour retinal environment could ensure the integrity of microvessels and the TGF-β supply, essential for controlling aberrant endothelial pruning and angiogenesis.

Inhibition of oocyte fertilization by assisted reproductive techniques and increased sperm DNA fragmentation in the presence of Candida albicans: a case report

The effects of Candida albicans on sperm parameters and the outcome of infertility treatment are unclear. This report describes a lack of fertilization after assisted reproductive techniques and increased sperm DNA fragmentation in an infertile patient with male accessory gland infection due to Candida albicans. He had normal sperm parameters and, therefore, underwent conventional IVF for a female factor of infertility. No spermatozoa or only one spermatozoon per oocyte were found attached to the zona pellucida of the six mature oocytes retrieved. A new semen sample was then requested from the patient to perform intracytoplasmic sperm injection (ICSI) on the same oocytes, but again no fertilization resulted. Candida albicans was detected in the medium where spermatozoa were co-incubated with oocytes and subsequently in the urethral swabs. It did not have any detrimental effect on sperm parameters soon after ejaculation or following separation of motile spermatozoa by swim-up technique. Fertilization failure after assisted reproduction treatment was associated with an increased percentage of motile spermatozoa having chromatin packaging abnormalities, externalization of phosphatidylserine and DNA fragmentation. In conclusion, Candida albicans did not affect sperm parameters, but increased sperm chromatin packaging damage and apoptosis that might have caused fertilization failure after assisted reproduction treatment in this couple.

VEGF receptor-1 involvement in pericyte loss induced by Escherichia coli in an in vitro model of blood brain barrier

The key aspect of neonatal meningitis is related to the ability of pathogens to invade the blood–brain barrier (BBB) and to penetrate the central nervous system. In the present study we show that, in an in vitro model of BBB, on the basis of co‐culturing primary bovine brain endothelial cells (BBEC) and primary bovine retinal pericytes (BRPC), Escherichia coli infection determines changes of transendothelial electrical resistance (TEER) and permeability (Pe) to sodium fluorescein. In the co‐culture model, within BBEC, bacteria are able to stimulate cytosolic and Ca2+‐independent phospholipase A2 (cPLA2 and iPLA2) enzyme activities. In supernatants of E. coli‐stimulated co‐cultures, an increase in prostaglandins (PGE2) and VEGF production in comparison with untreated co‐cultures were found. Incubation with E. coli in presence of AACOCF3 or BEL caused a decrease of PGE2 and VEGF release. SEM and TEM images of BBEC and BRPC showed E. coli adhesion to BBEC and BRPC but only in BBEC the invasion occurs. VEGFR‐1 but not VEGFR‐2 blockade by the specific antibody reduced E. coli invasion in BBEC. In our model of BBB infection, a significant loss of BRPC was observed. Following VEGFR‐1, but not VEGFR‐2 blockade, or in presence of AACOCF3 or BEL, elevated TEER values, reducedpermeability and BRPC loss were found. These data suggest that VEGFR‐1 negatively regulates BRPC survival and its blockade protects the barrier integrity. PGs and VEGF could exert a biological effect on BBB, probably by BRPC coverage ablation, thus increasing BBB permeability. Our results show the role played by the BBEC as well as BRPC during a bacterial attack on BBB. A better understanding of the mechanisms by which E. coli enter the nervous system and how bacteria alter the communication between endothelial cells and pericytes may provide exciting new insight for clinical intervention.

Candida albicans experimental infection: effects on human sperm motility, mitochondrial membrane potential and apoptosis

Studies suggest Candida albicans infection has a negative effect on sperm function, including fertilizing ability. Assisted reproduction treatment using spermatozoa from a patient with unrecognized C. albicans infection did not result in fertilization. Preliminary evidence suggested an effect on sperm motility and apoptosis. This study was undertaken to evaluate the effects of experimentally induced C. albicans infection on motility, membrane mitochondrial potential (MMP), chromatin packaging and apoptosis [membrane phosphatidylserine (PS) externalization and DNA fragmentation] of spermatozoa isolated from normozoospermic healthy men. Motile spermatozoa were isolated by swim-up from 13 normal volunteers and exposed to increasing concentrations (0, 1000, 10,000, and 100,000 cfu/ml) of the fungus for 3 and 24 h. C. albicans was isolated from vaginal swabs, after identification, freshly prepared for experiments. Following incubation, sperm motility decreased significantly (P < 0.05 from 10,000 cfu/ml) and spermatozoa with reduced MMP or PS externalization, an early sign of apoptosis, increased in a time- and concentration-dependent manner. Sperm DNA fragmentation and chromatin integrity increased slightly after exposure to C. albicans, but the increase did not reach statistical significance. This study showed that C. albicans infection may decrease the functional competence of spermatozoa by reducing motility and MMP and by promoting molecular apoptosis mechanisms.

Anti-angiogenic Therapy in Cancer: Downsides and New Pivots for Precision Medicine

Primary solid tumors originate close to pre-existing tissue vasculature, initially growing along such tissue blood vessels, and this phenomenon is important for the metastatic potential which frequently occurs in highly vascularized tissues. Unfortunately, preclinic and clinic anti-angiogenic approaches have not been very successful, and multiple factors have been found to contribute to toxicity and tumor resistance. Moreover, tumors can highlight intrinsic or acquired resistances, or show adaptation to the VEGF-targeted therapies. Furthermore, different mechanisms of vascularization, activation of alternative signaling pathways, and increased tumor aggressiveness make this context even more complex. On the other hand, it has to be considered that the transitional restoration of normal, not fenestrated, microvessels allows the drug to reach the tumor and act with the maximum efficiency. However, these effects are time-limited and different, depending on the various types of cancer, and clearly define a specific “normalization window.” So, new horizons in the therapeutic approaches consist on the treatment of the tumor with pro- (instead of anti-) angiogenic therapies, which could strengthen a network of well-structured blood vessels that facilitate the transport of the drug.

Involvement of PKCα–MAPK/ERK-phospholipase A2 pathway in the Escherichia coli invasion of brain microvascular endothelial cells

Escherichia coli K1 is the most common Gram-negative organism that causes neonatal meningitis following penetration of the blood-brain barrier. In the present study we demonstrated the involvement of cytosolic (cPLA(2)) and calcium-independent phospholipase A(2) (iPLA(2)) and the contribution of cyclooxygenase-2 products in E. coli invasion of microvascular endothelial cells. The traversal of bacteria did not determine trans-endothelial electrical resistance (TEER) and ZO-1 expression changes and was reduced by PLA(2)s siRNA. cPLA(2) and iPLA(2) enzyme activities and cPLA(2) phosphorylation were stimulated after E. coli incubation and were attenuated by PLA(2), PI3-K, ERK 1/2 inhibitors. Our results demonstrate the role of PKCα/ERK/MAPK signaling pathways in governing the E. coli penetration into the brain.