The Diagnostic Potential of the Human Blood Microbiome: Are We Dreaming or Awake?

Human blood has historically been considered a sterile environment. Recently, a thriving microbiome dominated by Firmicutes, Actinobacteria, Proteobacteria, and Bacteroidetes phyla was detected in healthy blood. The localization of these microbes is restricted to some blood cell populations, particularly the peripheral blood mononuclear cells and erythrocytes. It was hypothesized that the blood microbiome originates from the skin-oral-gut axis. In addition, many studies have evaluated the potential of blood microbiome dysbiosis as a prognostic marker in cardiovascular diseases, cirrhosis, severe liver fibrosis, severe acute pancreatitis, type 2 diabetes, and chronic kidney diseases. The present review aims to summarize current findings and most recent evidence in the field.

Gender-Specific Impact of Sex Hormones on the Immune System.

Sex hormones are key determinants of gender-related differences and regulate growth and development during puberty. They also exert a broad range modulation of immune cell functions, and a dichotomy exists in the immune response between the sexes. Both clinical and animal models have demonstrated that androgens, estrogens, and progestogens mediate many of the gender-specific differences in immune responses, from the susceptibility to infectious diseases to the prevalence of autoimmune disorders. Androgens and progestogens mainly promote immunosuppressive or immunomodulatory effects, whereas estrogens enhance humoral immunity both in men and in women. This study summarizes the available evidence regarding the physiological effects of sex hormones on human immune cell function and the underlying biological mechanisms, focusing on gender differences triggered by different amounts of androgens between males and females.

Externally Supported Extra-anatomical Venous Bypass to Treat Upper Limb Ischemia with Shoulder Prosthetic Infection.

To report a case of acute arm ischemia and prosthetic shoulder infection treated by extra-anatomical great saphenous vein graft with external vascular scaffolding. A 65 year-old man with multiple surgical interventions for soft tissue sarcoma of the right shoulder, local radiotherapy with residual brachial plexus neuropraxia, was referred to our attention for signs of arm ischemia. Two weeks before, the patient was submitted to prosthetic shoulder replacement complicated with prosthetic infection. Considering the mechanism of vascular injury, an open surgical revascularization was planned with a deliberate avoidance of the natural anatomic pathway to reduce the risk of graft infection. Consequently, after the complete removal of infected shoulder prosthesis and placement of antibiotic spacer, an axillarbrachial artery bypass using great saphenous vein was performed using a new braided cobalt chrome kink resistant external vascular support to prevent compression, also considering the extra-anatomical position of the graft. At 12 months' follow-up, patient was in good clinical condition with complete resolution of arm ischemia; computed tomographic angiography and duplex scan revealed patency of the graft with excellent distal perfusion. The new external vascular support seems to be useful and feasible for preventing compression of extra-anatomical venous bypass.

Disruption of Circadian Rhythms: A Crucial Factor in the Etiology of Infertility.

: Infertility represents a growing health problem in industrialized countries. Thus, a greater understanding of the molecular networks involved in this disease could be critical for the development of new therapies. A recent finding revealed that circadian rhythmicity disruption is one of the main causes of poor reproductive outcome. The circadian clock system beats circadian rhythms and modulates several physiological functions such as the sleep-wake cycle, body temperature, heart rate, and hormones secretion, all of which enable the body to function in response to a 24 h cycle. This intricated machinery is driven by specific genes, called "clock genes" that fine-tune body homeostasis. Stress of modern lifestyle can determine changes in hormone secretion, favoring the onset of infertility-related conditions that might reflect disfunctions within the hypothalamic-pituitary-gonadal axis. Consequently, the loss of rhythmicity in the suprachiasmatic nuclei might affect pulsatile sexual hormones release. Herein, we provide an overview of the recent findings, in both animal models and humans, about how fertility is influenced by circadian rhythm. In addition, we explore the complex interaction among hormones, fertility and the circadian clock. A deeper analysis of these interactions might lead to novel insights that could ameliorate the therapeutic management of infertility and related disorders.