Phenotypic Variability of Dystrophinopathy Symptomatic Female Carriers.

BACKGROUND: Dystrophinopathies are X-linked muscular dystrophies characterized by pathogenic mutations in the dystrophin gene. Symptomatic dystrophinopathy female carriers may present with limb-girdle weakness. The diagnosis may be challenging in the absence of affected male relatives. We aimed to describe the phenotypic variability in a series of molecular-confirmed female dystrophinopathy patients. METHODS: This is a retrospective analysis of medical records from 1997 to 2015. RESULTS: Ten female dystrophinopathy patients were selected, two with unusual phenotypes: one with early joint contractures muscular dystrophy and the other with very late onset myopathy. Muscle imaging studies demonstrated predominant asymmetric fat replacement. Muscle biopsy immunohistochemistry demonstrated clear mosaic pattern in two cases and only subtle reduction of dystrophin intensity in three. CONCLUSIONS: Adequate diagnosis is fundamental for genetic counseling and cardiologic follow-up. Female patients with dystrophinopathy may present unusual phenotypes such as early contractures and very late onset myopathy.

Muscle fat replacement and modified ragged red fibers in two patients with reversible infantile respiratory chain deficiency.

Reversible infantile respiratory chain deficiency is a severe neonatal mitochondrial myopathy that resolves spontaneously. It is caused by the homoplasmic m.14674T>C mtDNA mutation and additional nuclear variants in genes interacting with mt-tRNAGlu have been detected in some patients. We present detailed clinical, imaging, and muscle biopsy findings in a boy and a girl with neonatal hypotonia, feeding difficulties, lactic acidosis, and ragged red fibers. Both patients show fat replacement on muscle imaging, which was mild in the boy, but severe in the girl, affecting mostly the posterior leg muscles. In addition to the homoplasmic m.14674T>C, both patients carried heterozygous variants in QRSL1 (c. 686T>G; p.Val299Gly) and EARS2 (c.358C>T; p.Arg120Trp), respectively. It is very important to recognize the clinical and morphological signs of reversible infantile respiratory chain deficiency as patients should receive intensive supportive care in the first 6 months of life. Understanding the mechanism of the spontaneous recovery may lead to novel therapeutic perspectives in other mitochondrial diseases.

An Anticarsia gemmatalis multiple nucleopolyhedrovirus mutant, vApAg, induces hemocytes apoptosis in vivo and displays reduced infectivity in larvae of Anticarsia gemmatalis (Hübner) (Lepidoptera: Noctuidae).

An Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV) mutant, vApAg, induces apoptosis in a cell culture derived from Anticarsia gemmatalis (UFL-AG-286), reducing viral progeny. We have investigated apoptosis induction in vivo by vApAg in A. gemmatalis larvae and its correlation to infectivity reduction. LC(50), LD(50), LT(50) and the mean time to death of larvae were determined for vApAg and AgMNPV. Apoptosis was accessed for hemocytes of infected larvae using light and transmission electron microscopy. All types of hemocytes can be infected by vApAg. After 12h post-infection (h p.i.), typical cellular modifications associated to nucleopolyhedrovirus infection were observed. Apoptosis becomes evident after 24h p.i., and massive after 72h p.i. Necrosis of infected cells was also observed. Despite cell death, hemocytes produced budded viruses and polyhedra. Pl and gh1-type hemocytes presented phagocytic activity. Agarose gel electrophoresis revealed fragmentation of hemocytes DNA at late times post-infection. The LC(50) and LD(50) were between five- and six-fold higher for vApAg. The LT(50) and the mean time to death were higher for vApAg in a same treatment or for a similar mortality induced by AgMNPV. These results show correlation of apoptosis and the reduced infectivity of vApAg in A. gemmatalis larvae.

In vivo apoptosis induction and reduction of infectivity by an Autographa californica multiple nucleopolyhedrovirus p35(-) recombinant in hemocytes from the velvet bean caterpillar Anticarsia gemmatalis (Hübner) (Lepidoptera: Noctuidae).

Baculoviruses have long been shown to regulate apoptosis in cultured insect cells. Recently, this phenomenon was also reported to occur in vivo, reinforcing the importance of apoptosis in insect immunity against viruses. The vP35del virus, an Autographa californica multiple nucleopolyhedrovirus (AcMNPV) recombinant, was previously shown to induce apoptosis in Anticarsia gemmatalis cultured cells. In order to verify the AcMNPV interaction with hemocytes, apoptosis induction in vivo and its effects upon infectivity, we studied the course of intrahemocoelic infection of recombinant viruses (vHSGFP and vHSGFP/P35del) in A. gemmatalis larvae. Insect development and mortality were monitored and infection progress was followed by light, fluorescence and electron microscopy. For all doses tested, vHSGFP/P35del caused lower mortality than vHSGFP. Mortality of 95% occurred with a dose of 4x10(6) PFUs of vHSGFP, which was reduced to 60% for vHSGFP/P35del. GFP expression was first observed at 3 h p.i. for the two viruses, increasing for vHSGFP (40% at 120 h p.i.) and decreasing for vHSGFP/P35del (0% at 120 h p.i.). The virus vHSGFP/P35del induced apoptosis in hemocytes, with some budded virus being produced, and fragmented cells were observed between 24 and 72 h p.i. The recombinant vHSGFP induced typical wild-type cytopathic effects, with low production of occluded viruses until 120 h p.i. Plasmatocytes and granular hemocytes type 1 were the hemocytes most susceptible to both viruses. For these experimental conditions, we concluded that A. gemmatalis is a semi-permissive host to AcMNPV; moreover, apoptosis reduces AcMNPV infectivity and the p35 gene is essential for blocking apoptosis in this system.