Background Overweight and obesity are increasingly spread in our society. Low testosterone levels are often present in these patients, the so-called metabolic hypogonadism, that further alters the metabolic balance in a sort of vicious cycle. Very low-calorie ketogenic diet (VLCKD) has been reported to efficiently reduce body weight, glycaemia, and the serum levels of insulin, glycated hemoglobin, but its effects on β-cell function and total testosterone (TT) levels are less clear. Aim To evaluate the effects of VLCKD on markers suggested to be predictive of β-cell dysfunction development, such as proinsulin or proinsulin/insulin ratio, and on TT values in a cohort of overweight or obese nondiabetic male patients with metabolic hypogonadism. Methods Patients with overweight or obesity and metabolic hypogonadism underwent to VLCKD for 12 weeks. Anthropometric parameters, blood testing for the measurement of glycaemia, insulin, C-peptide, proinsulin, TT, calculation of body-mass index (BMI), and HOMA index were performed before VLCKD and after 12 weeks. Results Twenty patients (mean age 49.3 ± 5.2 years) were enrolled. At enrollement all patients presented increased insulin, HOMA index, C-peptide, and proinsulin levels, whereas the proinsulin/insulin ratio was within the normal values. After VLCKD treatment, body weight and BMI significantly decreased, and 14.9 ± 3.9% loss of the initial body weight was achieved. Glycaemia, insulin, HOMA index, C-peptide, and proinsulin significantly decreased compared to pre-VLCKD levels. Serum glycaemia, insulin, C-peptide, and proinsulin levels returned within the normal range in all patients. No difference in the proinsulin/insulin ratio was observed after VLCKD treatment. A mean increase of 218.1 ± 53.9% in serum TT levels was achieved and none of the patients showed TT values falling in the hypogonadal range at the end of the VLCKD treatment. Conclusions This is the first study that evaluated the effects of VLCKD on proinsulin, proinsulin/insulin ratio, and TT levels. VLCKD could be safely used to improve β-cell secretory function and insulin-sensitivity, and to rescue overweight and obese patients from β-cell failure and metabolic hypogonadism.

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Familial amyloidotic polyneuropathy (FAP) is a progressive neuropathy, with onset in adulthood and high mortality. It is related to an altered transthyretin (TTR) plasma protein, mainly produced by the liver and responsible for amyloid deposit in the peripheral nervous system. SNPs in the TTR gene were associated with FAP, and the G>C substitution (NM_000371.3:c.325G>C) in the 109th codon (GAG vs CAG; NP_362.1:p.E109Q) was previously described in Sicily (Italy). Here, we report on a Sicilian family with several patients affected by FAP related to the E109Q mutation, which displayed a somatic mosaicism with the reversion to normality of the c.325G>C mutation. After exclusion of isodisomy and allele deletion, this event seems to be due to a rare, post-zygotic interallelic gene conversion with the wild-type allele serving as a donor. Further investigations will be necessary to better understand the molecular basis of this phenomenon, and could help determine if this can be induced in a targeted manner in the context of natural gene therapy to treat TTR-related FAP patients, as previously proposed for other diseases. Moreover, our results confirm the need to perform DNA-based diagnostic tests with at least a second tissue when a suspected germline mutation in a candidate gene is not identified in the first tissue.

The isolation and analysis of nucleated fetal cells (NFCs) from maternal blood may represent a new approach to noninvasive prenatal diagnosis. Although promising, these techniques require highly accurate separation of NFCs from nucleated cells of maternal origin; the two major problems limiting these techniques are the relative rarity of fetal cells in maternal blood and the need to establish their fetal origin. We now report a novel procedure that has allowed accurate separation of NFCs from maternal cells. The technique reported involves direct micromanipulator isolation of histochemically identified hemoglobin F-positive nucleated cells to obtain fetal nucleated red blood cells (FNRBCs) of high yield and purity. Using this technique, followed by cell-by-cell multicolor fluorescence in situ hybridization (FISH) analysis of purified FNRBCs, we were able to detect some of the most common human aneuploidies (including Down syndrome, Klinefelter syndrome, and trisomy 13) in 33 pregnant women referred for amniocentesis. The procedure used, which can be completed in <72 hrs, produced complete concordance with the results of amniocentesis. We also confirm findings of prior studies suggesting that the number of FNRBCs in maternal circulation is remarkably higher in abnormal pregnancies than in normal pregnancies, especially in women carrying a fetus with trisomy 21.

Currently, prenatal detection of Down syndrome and other most common aneuploidies relies on invasive procedures such as amniocentesis and villocentesis, and on non-invasive screening tests such as second trimester maternal serum screening (Triple test), and first trimester screening (ULTRA-screen). However, it well known that invasive techniques carry a small risk of fetal loss, while both Triple test and ULTRA-screen are not diagnostic, may miss from 15 - 40 % of cases of Down syndrome, in addition to having a 5 - 8 % rate of false-positives. We now report clear evidence that the number of fetal nucleated red blood cells (FNRBCs) in the maternal circulation is remarkably higher in pregnant women carrying aneuploid fetuses, especially in cases of Down syndrome. These results are in agreement with the findings of other investigators using different methods, and suggest that the number of FNRBCs present in the maternal blood sample could be used as additional marker, in concert with existing screening tests, to improve non-invasive detection of Down syndrome, and other most common aneuploidies.