GDF15 linked to maternal risk of nausea and vomiting during pregnancy

GDF15, a hormone acting on the brainstem, has been implicated in the nausea and vomiting of pregnancy, including its most severe form, hyperemesis gravidarum (HG), but a full mechanistic understanding is lacking1-4. Here we report that fetal production of GDF15 and maternal sensitivity to it both contribute substantially to the risk of HG. We confirmed that higher GDF15 levels in maternal blood are associated with vomiting in pregnancy and HG. Using mass spectrometry to detect a naturally labelled GDF15 variant, we demonstrate that the vast majority of GDF15 in the maternal plasma is derived from the feto-placental unit. By studying carriers of rare and common genetic variants, we found that low levels of GDF15 in the non-pregnant state increase the risk of developing HG. Conversely, women with β-thalassaemia, a condition in which GDF15 levels are chronically high5, report very low levels of nausea and vomiting of pregnancy. In mice, the acute food intake response to a bolus of GDF15 is influenced bi-directionally by prior levels of circulating GDF15 in a manner suggesting that this system is susceptible to desensitization. Our findings support a putative causal role for fetally derived GDF15 in the nausea and vomiting of human pregnancy, with maternal sensitivity, at least partly determined by prepregnancy exposure to the hormone, being a major influence on its severity. They also suggest mechanism-based approaches to the treatment and prevention of HG.

Fetally-encoded GDF15 and maternal GDF15 sensitivity are major determinants of nausea and vomiting in human pregnancy

Human pregnancy is frequently accompanied by nausea and vomiting that may become severe and life-threatening, as in hyperemesis gravidarum (HG), the cause of which is unknown. Growth Differentiation Factor-15 (GDF15), a hormone known to act on the hindbrain to cause emesis, is highly expressed in the placenta and its levels in maternal blood rise rapidly in pregnancy. Variants in the maternal GDF15 gene are associated with HG. Here we report that fetal production of GDF15, and maternal sensitivity to it, both contribute substantially to the risk of HG. We found that the great majority of GDF15 in maternal circulation is derived from the feto-placental unit and that higher GDF15 levels in maternal blood are associated with vomiting and are further elevated in patients with HG. Conversely, we found that lower levels of GDF15 in the non-pregnant state predispose women to HG. A rare C211G variant in GDF15 which strongly predisposes mothers to HG, particularly when the fetus is wild-type, was found to markedly impair cellular secretion of GDF15 and associate with low circulating levels of GDF15 in the non-pregnant state. Consistent with this, two common GDF15 haplotypes which predispose to HG were associated with lower circulating levels outside pregnancy. The administration of a long-acting form of GDF15 to wild-type mice markedly reduced subsequent responses to an acute dose, establishing that desensitisation is a feature of this system. GDF15 levels are known to be highly and chronically elevated in patients with beta thalassemia. In women with this disorder, reports of symptoms of nausea or vomiting in pregnancy were strikingly diminished. Our findings support a causal role for fetal derived GDF15 in the nausea and vomiting of human pregnancy, with maternal sensitivity, at least partly determined by pre-pregnancy exposure to GDF15, being a major influence on its severity. They also suggest mechanism-based approaches to the treatment and prevention of HG.

Effect of the drying conditions on the microstructure of silica based xerogels and aerogels

Nanostructured silica based xerogels and aerogels are prepared by sol-gel technology, using methyltrimethoxysilane as precursor. The influence of the drying method and conditions on the microstructure of the obtained materials is investigated, since the drying stage has a critical influence on their porosity. Two types of drying methods were used: atmospheric pressure drying (evaporative), to produce xerogels, and supercritical fluids drying, to obtain aerogels. Although the supercritical fluids drying technique is more expensive and hazardous than the atmospheric pressure drying, it is well known that aerogels are less dense than the xerogels due to less pore shrinkage. However, the ideal situation would be to use atmospheric pressure drying in conditions that minimize the pore collapse. Therefore, in this work, different temperature cycles for atmospheric pressure drying and two heating rates for the supercritical fluids drying are tested to study the gels' shrinkage by analyzing the density and porosity properties of the final materials. The best materials obtained are aerogels dried with the lower heating rate (approximately 80 degrees C/h), since they exhibit very low bulk density (approximately 50 kg/m3), high porosity (95%)-mainly micro and mesopores, high surface area (approximately 500 m2/g), moderate flexibility and a remarkable hydrophobic character (>140 degrees). It was proved that the temperature cycles of atmospheric pressure drying can be tuned to obtain xerogels with properties comparable to those of aerogels, having a bulk density only approximately15 kg/m3 higher. All the synthesized materials fulfill the requirements for application as insulators in Space environments.

An activating mutation of AKT2 and human hypoglycemia

Pathological fasting hypoglycemia in humans is usually explained by excessive circulating insulin or insulin-like molecules or by inborn errors of metabolism impairing liver glucose production. We studied three unrelated children with unexplained, recurrent, and severe fasting hypoglycemia and asymmetrical growth. All were found to carry the same de novo mutation, p.Glu17Lys, in the serine/threonine kinase AKT2, in two cases as heterozygotes and in one case in mosaic form. In heterologous cells, the mutant AKT2 was constitutively recruited to the plasma membrane, leading to insulin-independent activation of downstream signaling. Thus, systemic metabolic disease can result from constitutive, cell-autonomous activation of signaling pathways normally controlled by insulin.

Founder effect in the Horn of Africa for an insulin receptor mutation that may impair receptor recycling

AIMS/HYPOTHESIS

Genetic insulin receptoropathies are a rare cause of severe insulin resistance. We identified the Ile119Met missense mutation in the insulin receptor INSR gene, previously reported in a Yemeni kindred, in four unrelated patients with Somali ancestry. We aimed to investigate a possible genetic founder effect, and to study the mechanism of loss of function of the mutant receptor.

METHODS

Biochemical profiling and DNA haplotype analysis of affected patients were performed. Insulin receptor expression in lymphoblastoid cells from a homozygous p.Ile119Met INSR patient, and in cells heterologously expressing the mutant receptor, was examined. Insulin binding, insulin-stimulated receptor autophosphorylation, and cooperativity and pH dependency of insulin dissociation were also assessed.

RESULTS

All patients had biochemical profiles pathognomonic of insulin receptoropathy, while haplotype analysis revealed the putative shared region around the INSR mutant to be no larger than 28 kb. An increased insulin proreceptor to β subunit ratio was seen in patient-derived cells. Steady state insulin binding and insulin-stimulated autophosphorylation of the mutant receptor was normal; however it exhibited decreased insulin dissociation rates with preserved cooperativity, a difference accentuated at low pH.

CONCLUSIONS/INTERPRETATION

The p.Ile119Met INSR appears to have arisen around the Horn of Africa, and should be sought first in severely insulin resistant patients with ancestry from this region. Despite collectively compelling genetic, clinical and biochemical evidence for its pathogenicity, loss of function in conventional in vitro assays is subtle, suggesting mildly impaired receptor recycling only.

Cutaneous manifestations of familial amyloidotic polyneuropathy

Familial amyloidotic polyneuropathy is an autosomal dominant amyloidosis, characterized by the systemic deposition of amyloid with a particular involvement of the peripheral nerves. The disease generally manifests as a severe sensory, motor and autonomic neuropathy. Cardiomyopathy, nephropathy, vitreous opacities and carpal tunnel syndrome may occur in a variable association with the neuropathy. Trophic dermatological lesions are frequent in the more advanced stages of the disease. We examined the skin of 142 patients. The cutaneous manifestations more frequently observed were: xerosis (81.6%), seborrheic dermatitis (21.8%), traumatic and burn lesions (19.7%), acne (18.3%), neurotrophic ulcers (14%) and onychomycosis (10.5%). Among the hepatic transplanted patients (31%), seborrheic dermatitis and acne were the most frequent diagnoses.

Tremor as the first neurological manifestation of Sneddon's syndrome

We report on a 54-year-old woman with Sneddon's syndrome manifested by livedo reticularis, fetal losses, hypertension, and high antinuclear antibody titres. At the age of 42 years she developed tremor of the trunk, limbs, and head only in the standing position that interfered with walking, followed some years later by cognitive decline and a parkinsonian syndrome. T2-weighted brain magnetic resonance imaging showed high signal in cortical areas, basal ganglia, midbrain, and cerebellum.

Plasma cell cheilitis

Plasma cell cheilitis is a rare inflammatory disorder of the lip with a characteristic band-like infiltrate of plasma cells in the upper dermis. Differential diagnosis should consider allergic/irritant contact cheilitis, candidiasis, syphilis, Queyrat's erythroplasia, granulomatous cheilitis, plasmoacanthoma, plasmacytoma, squamous cell carcinoma and exfoliative or factitious cheilitis. We observed plasma cell cheilitis in a 60-year-old Caucasian female who had a partial response to topical steroids and oral griseofulvin.

296LIPIDIC CONTENT IN JERSEY BLASTOCYSTS COMPARED WITH HOLSTEIN AND IVP EMBRYOS

The objective of this study was to compare the ultrastructure of bovine embryos from different breeds and origin in terms of lipid contents. Jersey and Holstein embryos produced in vivo were obtained from superovulated donors by non-surgical method 7 days after AI. Embryos produced in vitro (Holstein cross breed) were obtained from cumulus-oocytes complexes (COC) aspirated from slaughterhouse ovaries. The COC were matured and fertilized in vitro. The zygotes were cultivated in vitro for 7 days in SOFaa media. Embryos produced in vivo (Holstein n=5; Jersey n=5) and in vitro (n=5) classified as blastocyts grade II were fixed in Karnovsky solution immediately after embryo recovery or embryo culture and prepared for microscopic electronic evaluation. Ultrastructure of inner cell mass and trophoblast cells was analyzed. Morphometry on electron microscopy was performed using a point-count method in random samples of electron micrographs of each embryo category. The data were analyzed by chi square test. The volume density occupied by number of lipid droplets was greater in Jersey and in vitro-produced embryos compared with Holstein embryos (24.3%±11.7; 28.4%±19.6 and 9%±6.68, respectively, P<0,05).

[Hospital outcome and short-term follow-up of elderly patients presenting to the emergency unit with congestive heart failure]

PURPOSE

To evaluate the in-hospital (IH) outcome and the short-term follow-up of predominantly elderly patients presenting to an emergency room (ER) with congestive heart failure (CHF).

METHODS

In an 11 month period, 57 patients presenting to the ER with CHF were included. Mean age was 69 +/- 15 years (27 to 94) and 39 (68.4%) were male. CHF diagnosis was based on the Boston criteria. We evaluated IH outcome and prognosis in a mean follow-up of 5.7 +/- 2.7 months (1 to 12). In addition, some mortality predictors and mechanisms of death according on the ACME system were identified.

RESULTS

Eight patients (14%) died in the IH period. Modes of death were circulatory failure (CF) in 7, and peri-operative (PO) in one (aortic valve replacement). During follow-up 9 deaths occurred. Five were due to CF, 2 were sudden and 2 were PO (mitral valve replacement and ventriculectomy). Six-months and 1-year survival rates of the patients who were discharged were 82% and 66%, respectively. Sodium lower than 135 mEq/l (p = 0.004) and female gender (p = 0.038) were independent predictors of mortality.

CONCLUSION

Elderly patients with CHF admitted to the ER have high in-hospital and short-term follow up mortalities. The majority die from CF due to worsening heart failure.

[Coronary artery dissection without acute myocardial infarction]

A 57 year-old-man with acute aortic dissection (DeBakey type I) who developed right coronary artery dissection without acute myocardial infarction. He was successful surgically treated and became asymptomatic.

[Myocardial revascularization in left coronary trunk lesion in patients over 65 years old]

PURPOSE

To study the short and long-term follow-up of patients with left main coronary artery disease (LMCAD) and age over 65 years, by comparing the results with patients under 65 years-old.

METHODS

Twenty-two patients with LMCAD and mean age of 69 +/- 3.5 years (group I) were underwent isolated coronary artery bypass grafting (CABG) and compared to 31 patients with LMCAD, mean age of 54 +/- 7 years (group II), who also underwent isolated CABG. The life-table Kaplan-Meyer method was used to estimate the post-operative survival. The chi-square and Student "t" test were used when necessary.

RESULTS

Despite higher operative mortality in group I (9.1% x 3.2%), the difference was statistically not significant. The operative morbidity was similar in both groups. Actuarial survival at 4 years was 85% in group I and 95% in group II. Actuarial survival free of cardiac events was 69% in group II and 75% in group II.

CONCLUSION

The CABG is well tolerated and had low morbidity and acceptable mortality in old patients with LMCAD. The long-term survival in these patients was very similar to the younger patients.

Immunohistochemical characterisation of probable intravascular haematopoiesis in the vasa rectae of the renal medulla in acute tubular necrosis

Immunohistochemistry was applied to identify the nature of the nucleated cells that accumulate in the vasa rectae of the corticomedullary junction in acute tubular necrosis. In all 6 cases studied, there were intravascular cells that reacted with monoclonal antibodies to erythroblast, macrophages, myeloid cells, T and B lymphocytes and rare megakaryocytes. The findings are consistent with the occurrence of intravascular haematopoiesis in the renal medulla in acute tubular necrosis.

Case report: cyclosporin A-induced neurotoxicity

Acute encephalopathy is a recognized toxic effect of Cyclosporin A (CsA) in organ transplantation recipients. A 16-year-old girl presented with acute encephalopathy 2 weeks after CsA and methylprednisolone medication for idiopathic uveitis. Magnetic resonance imaging showed cortical and white matter occipital changes, which were not visible 2 months later. With expanding indication for CsA use, an increasing number of neurotoxic cases are to be expected.