Bi‐allelic IARS mutations in a child with intra‐uterine growth retardation,neonatal cholestasis,and mild developmental delay

Recently, bi‐allelic mutations in cytosolic isoleucyl‐tRNA synthetase (IARS) have been described in three individuals with growth delay, hepatic dysfunction, and neurodevelopmental disabilities. Here we report an additional subject with this condition identified by whole‐exome sequencing. Our findings support the association between this disorder and neonatal cholestasis with distinct liver pathology. Furthermore, we provide functional data on two novel missense substitutions and expand the phenotype to include mild developmental delay, skin hyper‐elasticity, and hypervitaminosis D.     

Effectiveness of glycoprotein IIb/IIIa inhibitor use during primary coronary angioplasty: results of propensity analysis using the New York State Percutaneous Coronary Intervention Reporting System

Patients undergoing primary angioplasty in clinical practice experience a higher risk for adverse events than those enrolled in clinical trials. Whether glycoprotein (GP) IIb/IIIa inhibitor use during primary angioplasty is both safe and effective in real life is unknown. Therefore, we examined the pattern of GP IIb/IIIa use and its effectiveness in a large population-based cohort of 7,321 patients who underwent primary angioplasty in New York State. Propensity analysis was used to account for the nonrandomized use of GP IIb/IIIa inhibitors. Overall, 78.5% of patients who underwent primary angioplasty received GP IIb/IIIa inhibitors. In-hospital mortality was significantly lower with GP IIb/IIIa use (3% vs 6.2%, p <0.0001) after adjustment for both propensity score (odds ratio 0.57, 95% confidence interval 0.44 to 0.74, p <0.0001) and the combination of propensity score and clinical characteristics (odds ratio 0.63, 95% confidence interval 0.45 to 0.88, p = 0.006). Patients with older age and higher Mayo Clinic Risk Score (MCRS) received GP IIb/IIIa inhibitors less often. However, stratified analysis of patients with low to moderate risk (MCRS <12) versus high risk (>or=12) demonstrated that GP IIb/IIIa use lowered risk of mortality both in low- to moderate-risk (1.39% vs 3.23%, p <0.0001) and high-risk patients (16.15% vs 22.41%, p = 0.03). In conclusion, adjunct GP IIb/IIIa inhibitor use during primary angioplasty is effective and associated with improved in-hospital survival rates.     

Protein kinase C alpha modulates microvascular reactivity in the human coronary and skeletal microcirculation

BACKGROUND: Cardioplegic arrest (CP) and cardiopulmonary bypass (CPB) can lead to dysfunction in the coronary and skeletal microcirculation leading to impaired tissue perfusion. alpha-Adrenergic signaling pathways acting on these microcirculatory beds are thought to involve protein kinase C (PKC). We investigate here the role of the conventional PKCs in microvascular function in the setting of CP/CPB. METHODS: Atrial and skeletal muscle was harvested from 30 patients undergoing cardiac surgery before and after CP/CPB. Microvessels were used for Western blotting and immunofluorescent staining against conventional PKCs. Microvascular constriction was assessed in pre- and post-CP/CPB samples in response to alpha-adrenergic stimulation with phenylephrine, with and without a PKC-alpha inhibitor or PKC-alpha activator. PKC activity was assessed in isolated microvessels. RESULTS: Western blotting and immunostaining demonstrated only PKC-alpha in coronary and skeletal microvessels. CP/CPB diminished contractile responses to phenylephrine in coronary and skeletal samples. Inhibition of PKC-alpha reduced phenylephrine induced vasoconstriction in coronary and skeletal microvessels, whereas activation of PKC-alpha-augmented phenylephrine induced responses. PKC activity was decreased in coronary microvessels and to an even greater degree in skeletal microvessels after CP/CPB. CONCLUSIONS: PKC-alpha is the predominant conventional PKC present in the human coronary and skeletal microcirculation. It likely plays a key role in alpha-adrenergic signaling in microvessels and in the vasomotor dysfunction after CP/CPB.     

Germline LEMD3 mutations are rare in sporadic patients with isolated melorheostosis

To further explore the allelic heterogeneity within the group of LEMD3-related disorders, we have screened a larger series of patients including 5 probands with osteopoikilosis or Buschke-Ollendorff syndrome (BOS), 2 families with the co-occurrence of melorheostosis and BOS, and 12 unrelated patients with isolated melorheostosis. Seven novel LEMD3 mutations were identified, all predicted to result in loss-of-function of the protein. We confirm that loss-of-function mutations in the LEMD3 gene can result in either osteopoikilosis or BOS. However, LEMD3 germline mutations were only found in two melorheostosis patients belonging to a different BOS family and one sporadic patient with melorheostosis. The additional presence of osteopoikilosis lesions in these patients seemed to distinguish them from the group of sporadic melorheostosis patients where no germline LEMD3 mutation was identified. Somatic mosaicism for a LEMD3 mutation in the latter group was also not observed, and therefore we must conclude that the genetic defect in the majority of sporadic and isolated melorheostosis remains unknown.     

Does paternal antigen-induced secretion of interleukin-10 by T regulatory cells mediate the birth order effect?

Childhood allergy constitutes a significant burden of disease in the Western world. The prevalence of this condition is highest in first born children, an as yet unresolved phenomenon called the "birth order effect". The hygiene hypothesis attempted to explain this differential risk by stating that less exposure to microbial agents at an early age of first born children would result in reduced activation of the immune system and subsequent polarization towards a Th2 phenotype. However, no conclusive evidence for or against the hygiene hypothesis has been found so far. Another, not necessarily conflicting, theory states that the birth order effect is already established during prenatal life and that the fetal-maternal interaction changes during successive pregnancies. Combining this theory with research on preeclampsia, another disease originating in pregnancy and also related to birth order, could suggest clues about the mechanisms underlying the birth order effect. Recent research on preeclampsia showed that preeclamptic women have higher levels of pro-inflammatory IL-6 and lower paternal antigen-induced secretion of IL-10 compared to normal pregnant women, indicating a lower number or lower functional activity of T regulatory (Treg) cells. These Treg cells play an important role in maintaining tolerance to fetal antigens in pregnancy and they are found in high numbers at the maternal-fetal interface. We hypothesize that nulliparous women have a lower activity of Treg cells specific to paternal antigens compared to parous women, either in peripheral blood or in the decidua (maternal part of the fetal-maternal interface). If this hypothesis is true, this would mean that the allergen suppressor mechanism of Treg cells is sub-optimal in first born children. This would explain at least a part of the mechanism of the birth order effect and would give us directions for developing preventive measures to prevent possibly 30% of future childhood allergies.     

The expanding panorama of split hand foot malformation

The split hand/foot malformation is a developmental defect of the extremities resulting from errors in the initiation and maintenance of the apical ectodermal ridge. The phenotype is genetically heterogeneous, and it can be identified either as an isolated phenotypic manifestation or as a constituent component of a malformation syndrome. This overview describes the clinical phenotype, related animal models, and the evolving genetic heterogeneity of the malformation.     

Postoperative spinal adhesive arachnoiditis presenting with hydrocephalus and cauda equina syndrome

To our knowledge, the association between hydrocephalus and postoperative spinal adhesive arachnoiditis (SAA) has never been reported. Herein we describe an unusual case of a 45-year-old man with spinal adhesive arachnoiditis (SAA) who developed delayed-onset hypertensive hydrocephalus and cauda equina syndrome (CES) after multiple low-back surgeries. The patient's clinical presentation, imaging findings, surgical management, and the possible mechanisms are discussed in the light of the present literature.     

Aprotinin in cardiac surgery

Aprotinin is a naturally occurring serine protease inhibitor that is being used with increasing frequency in cardiac surgery and beyond to reduce blood loss and the need for perioperative blood transfusion. Through inhibition of serine proteases such as plasmin, aprotinin significantly reduces fibrinolysis, thereby aiding hemostasis during surgical procedures. In addition, aprotinin interacts with other factors in the coagulation and fibrinolytic cascade, creating a hemostatic balance, without increasing the risk of thrombosis. These proven benefits are supplemented by the anti-inflammatory properties of aprotinin, which may help curb some of the deleterious effects of cardiopulmonary bypass. This article will review the discovery of aprotinin, its mechanism of action, dosing and adverse effects, and highlight the major recent trials demonstrating its efficacy.     

Retrospective diagnosis of chondrodysplasia punctata

The diagnosis of punctate epiphyseal dysplasia (PED) after disappearance of puncta is problematical. In some instances, however, the phenotypic and radiographic characteristics may persist and permit a retrospective diagnosis of PED in persons with unclassified bone dysplasia or bone changes of unknown origin. We report a boy aged 8 years who presented with unusual bony abnormalities that were consistent with a diagnosis of PED.