Case report of aplastic anaemia detected in third trimester of pregnancy: dilemmas faced

Aplastic anaemia with pregnancy is rarely encountered. Management of aplastic anaemia in pregnancy primarily involves a multidisciplinary approach offering supportive care. Our case was challenging as she developed aplastic anaemia during the third trimester and had refractory thrombocytopenia. She required platelet transfusions on a daily basis for few weeks as well as packed red blood cells frequently. Her leucocyte count was low initially but improved quickly unlike the platelet counts. Initiation of immunosuppressive therapy turned out to be beneficial and culminated in a good outcome. After starting immunosuppressive therapy with eltrombopag and cyclosporine she drifted through term and achieved a normal vaginal delivery

EPG5-related Vici syndrome: a paradigm of neurodevelopmental disorders with defective autophagy

Vici syndrome is a progressive neurodevelopmental multisystem disorder due to recessive mutations in the key autophagy gene EPG5. We report genetic, clinical, neuroradiological, and neuropathological features of 50 children from 30 families, as well as the neuronal phenotype of EPG5 knock-down in Drosophila melanogaster. We identified 39 different EPG5 mutations, most of them truncating and predicted to result in reduced EPG5 protein. Most mutations were private, but three recurrent mutations (p.Met2242Cysfs*5, p.Arg417*, and p.Gln336Arg) indicated possible founder effects. Presentation was mainly neonatal, with marked hypotonia and feeding difficulties. In addition to the five principal features (callosal agenesis, cataracts, hypopigmentation, cardiomyopathy, and immune dysfunction), we identified three equally consistent features (profound developmental delay, progressive microcephaly, and failure to thrive). The manifestation of all eight of these features has a specificity of 97%, and a sensitivity of 89% for the presence of an EPG5 mutation and will allow informed decisions about genetic testing. Clinical progression was relentless and many children died in infancy. Survival analysis demonstrated a median survival time of 24 months (95% confidence interval 0–49 months), with only a 10th of patients surviving to 5 years of age. Survival outcomes were significantly better in patients with compound heterozygous mutations (P = 0.046), as well as in patients with the recurrent p.Gln336Arg mutation. Acquired microcephaly and regression of skills in long-term survivors suggests a neurodegenerative component superimposed on the principal neurodevelopmental defect. Two-thirds of patients had a severe seizure disorder, placing EPG5 within the rapidly expanding group of genes associated with early-onset epileptic encephalopathies. Consistent neuroradiological features comprised structural abnormalities, in particular callosal agenesis and pontine hypoplasia, delayed myelination and, less frequently, thalamic signal intensity changes evolving over time. Typical muscle biopsy features included fibre size variability, central/internal nuclei, abnormal glycogen storage, presence of autophagic vacuoles and secondary mitochondrial abnormalities. Nerve biopsy performed in one case revealed subtotal absence of myelinated axons. Post-mortem examinations in three patients confirmed neurodevelopmental and neurodegenerative features and multisystem involvement. Finally, downregulation of epg5 (CG14299) in Drosophila resulted in autophagic abnormalities and progressive neurodegeneration. We conclude that EPG5-related Vici syndrome defines a novel group of neurodevelopmental disorders that should be considered in patients with suggestive features in whom mitochondrial, glycogen, or lysosomal storage disorders have been excluded. Neurological progression over time indicates an intriguing link between neurodevelopment and neurodegeneration, also supported by neurodegenerative features in epg5-deficient Drosophila, and recent implication of other autophagy regulators in late-onset neurodegenerative disease

Two Rare Syndromic Syndactyly Cases in Neonates

Introduction Isolated findings of syndactyly are benign. However, syndactyly can be associated with rare syndromes that need to be diagnosed for further management and for genetic counseling. Methods We present two cases of syndromic syndactyly in neonates. The first case is a 13-day-old female neonate with dysmorphic features. The neonate had clinical features of prominent forehead, hypertelorism, widely separated sagittal and metopic sutures, down-slanting eyes, low set ears, depressed nasal bridge, micrognathia, cleft palate, pectus excavatum, brachydactyly, and syndactyly of the second to fourth fingers bilaterally in upper limbs and in lower limbs. The second case is a 10-day-old male neonate with dysmorphism in the form of cleft alveolar ridge and palate, hyperplastic frenula, hypoplastic alar cartilage, syndactyly of the left hand, clinodactyly of the left lower limb toes, and amniotic bands. Discussion Case 1 was diagnosed as otopalatodigital syndrome because of the characteristic clinical features. This is a rare syndrome associated with syndactyly that often goes undiagnosed. Otopalatodigital syndrome spectrum disorders comprise of four phenotypically related conditions: otopalatodigital syndrome types 1 and 2, frontometaphyseal dysplasia, and Melnick–Needles syndrome. As it is associated with x-linked inheritance, its severity is more in males. Case 2 was diagnosed to have orofaciodigital syndrome because of the characteristic clinical features. It is another rare syndrome associated with syndactyly having abnormalities in the development of the oral cavity, face, and digits along with intellectual disability and renal system impairment. Conclusion There are fewer publications on these syndromes as they are rare and diagnosis is difficult. Recognizing these syndromes is key to further management and for genetic counseling

Processing, structure, and properties of gel spun PAN and PAN/CNT fibers and gel spun PAN based carbon fibers

Polyacrylonitrile (PAN) and PAN/carbon nanotube (PAN/CNT) fibers were manufactured through dry-jet wet spinning and gel spinning. Fiber coagulation occurred in a solvent-free or solvent/nonsolvent coagulation bath mixture with temperatures ranging from -50 to 25 degrees C. The effect of fiber processing conditions was studied to understand their effect on the as-spun fiber cross-sectional shape, as well as the as-spun fiber morphology. Increased coagulation bath temperature and a higher concentration of solvent in the coagulation bath medium resulted in more circular fibers and smoother fiber surface. as-spun fibers were then drawn to investigate the relationship between as-spun fiber processing conditions and the drawn precursor fiber structure and mechanical properties. PAN precursor fiber tows were then stabilized and carbonized in a continuous process for the manufacture of PAN based carbon fibers. Carbon fibers with tensile strengths as high as 5.8 GPa and tensile modulus as high as 375 GPa were produced. The highest strength PAN based carbon fibers were manufactured from as-spun fibers with an irregular cross-sectional shape produced using a -50 degrees C methanol coagulation bath, and exhibited a 61% increase in carbon fiber tensile strength as compared to the carbon fibers manufactured with a circular cross-section.close

Polyacrylonitrile solution homogeneity study by dynamic shear rheology and the effect on the carbon fiber tensile strength

Poly(acrylonitrile-co-methacrylic acid) (PAN-co-MAA)/N,N-dimethylformamide (DMF) solutions were prepared and dynamic shear rheology of these solutions were investigated. With increasing stirring time up to 72 h at 70??C, the polymer solution became less elastic (more liquid-like) with a ???60% reduction in the zero-shear viscosity. Relaxation spectra of the PAN-co-MAA/DMF solutions yield a decrease in relaxation time (disentanglement time, ??d), corresponding to an about 8% decrease in viscosity average molecular weight. The log-log plot of G??? (storage modulus) versus G??? (loss modulus) exhibited an increase in slope as a function of stirring time, suggesting that the molecular level solution homogeneity increased. In order to study the effect of solution homogeneity on the resulting carbon fiber tensile strength, multiple PAN-co-MAA/DMF solutions were prepared, and the precursor fibers were processed using gel-spinning, followed by continuous stabilization and carbonization. The rheological properties of each solution were also measured and correlated with the tensile strength values of the carbon fibers. It was observed that with increasing the slope of the G??? versus G??? log-log plot from 1.471 to 1.552, and reducing interfilament fiber friction during precursor fiber drawing through the addition of a fiber washing step prior to fiber drawing, the carbon fiber strength was improved (from 3.7 to 5.8 GPa). This suggests that along with precursor fiber manufacturing and carbonization, the solution homogeneity is also very important to obtain high strength carbon fiber. POLYM. ENG. SCI., 56:361–370, 2016. © 2016 Society of Plastics Engineer

Correlation between inhomogeneity in polyacrylonitrile spinning dopes and carbon fiber tensile strength

The nano-scale and micro-scale inhomogeneity of polyacrylonitrile (PAN) spinning dopes obtained from dynamic light scattering (DLS) experiment is correlated with the tensile strength of the resulting carbon fiber. The nanoscale inhomogeneity was estimated by calculating the diffusion coefficients from the slow relaxation mode of polymer solutions in DLS. The nanoscale inhomogeneity in the spinning dopes was found to be in the range of 1-45 nm. We also demonstrate mean of the count rate (MCR) obtained from DLS of PAN solution as a tool to detect the microscale inhomogeneity in the spinning dope for the first time. The MCR of spinning dopes varied from similar to 10.0 to 77.5 kcps (kilo-counts per second). The tensile strength of carbon fibers from the precursor fiber spun from the spinning dopes in this study varied from 3 to 5.2 GPa. Correlation studies show that the microscale inhomogeneity in the spinning dope was a major contributor to the decrease in the tensile strength of carbon fibers in the range of 3-4.5 GPa. Contaminants causing microscale inhomogeneity in PAN powder were removed by using micelles, reverse micelles and frothing. The surfactant treated PAN polymer was characterized using a fourier transform infrared spectroscope, differential scanning calorimeter, and thermal gravimetic analyzer to demonstrate complete removal of surfactants

High strength and high modulus carbon fibers

Carbon fibers have been processed from gel spun polyacrylonitrile copolymer on a continuous carbonization line at Georgia Tech (GT) with a tensile strength in the range of 5.5-5.8 GPa, and tensile modulus in the range of 354-375 GPa. This combination of strength and modulus is the highest for any continuous fiber reported to date, and the gel spinning route provides a pathway for further improvements in strength and modulus for mass production of carbon fibers. At short gauge length, fiber tensile strength was as high as 12.1 GPa, which is the highest value ever reported for a PAN based carbon fiber. Structure analysis shows random flaws of about 2 nm size, which results in limiting tensile strength of higher than 20 GPa. Inter-planar turbostratic graphite shear modulus in high strength carbon fibers is 30 GPa, while in graphite the corresponding value is only 4 GPa. © 2015 Elsevier Ltd.All rights reserved.close3

A liver enhancer in the fibrinogen gene cluster

The plasma concentration of fibrinogen varies in the healthy human population between 1.5 and 3.5 g/L. Understanding the basis of this variability has clinical importance because elevated fibrinogen levels are associated with increased cardiovascular disease risk. To identify novel regulatory elements involved in the control of fibrinogen expression, we used sequence conservation and in silico–predicted regulatory potential to select 14 conserved noncoding sequences (CNCs) within the conserved block of synteny containing the fibrinogen locus. The regulatory potential of each CNC was tested in vitro using a luciferase reporter gene assay in fibrinogen-expressing hepatoma cell lines (HuH7 and HepG2). 4 potential enhancers were tested for their ability to direct enhanced green fluorescent protein expression in zebrafish embryos. CNC12, a sequence equidistant from the human fibrinogen alpha and beta chain genes, activates strong liver enhanced green fluorescent protein expression in injected embryos and their transgenic progeny. A transgenic assay in embryonic day 14.5 mouse embryos confirmed the ability of CNC12 to activate transcription in the liver. While additional experiments are necessary to prove the role of CNC12 in the regulation of fibrinogen, our study reveals a novel regulatory element in the fibrinogen locus that is active in the liver and may contribute to variable fibrinogen expression in humans