Dysferlin is a plasma membrane protein and is expressed early in human development

Recently, a single gene, DYSF, has been identified which is mutated in patients with limb-girdle muscular dystrophy type 2B (LGMD2B) and with Miyoshi myopathy (MM). This is of interest because these diseases have been considered as two distinct clinical conditions since different muscle groups are the initial targets. Dysferlin, the protein product of the gene, is a novel molecule without homology to any known mammalian protein. We have now raised a monoclonal antibody to dysferlin and report on the expression of this new protein: immunolabelling with the antibody (designated NCL-hamlet) demonstrated a polypeptide of approximately 230 kDa on western blots of skeletal muscle, with localization to the muscle fibre membrane by microscopy at both the light and electron microscopic level. A specific loss of dysferlin labelling was observed in patients with mutations in the LGMD2B/MM gene. Furthermore, patients with two different frameshifting mutations demonstrated very low levels of immunoreactive protein in a manner reminiscent of the dystrophin expressed in many Duchenne patients. Analysis of human fetal tissue showed that dysferlin was expressed at the earliest stages of development examined, at Carnegie stage 15 or 16 (embryonic age 5-6 weeks). Dysferlin is present, therefore, at a time when the limbs start to show regional differentiation. Lack of dysferlin at this critical time may contribute to the pattern of muscle involvement that develops later, with the onset of a muscular dystrophy primarily affecting proximal or distal muscles

Molecular and functional diversity of neural connexins in the retina

Electrical synapses (gap junctions) in neuronal circuits have become a major focus in the study of network properties such as synchronization and oscillation (Galarreta and Hestrin, 1999; Gibson et al., 1999). Despite the recent progress made in unraveling the contribution of gap junctions to network behavior, little is known about the molecular composition of the junctional constituents. By cloning gap junction proteins [connexins (Cxs)] from zebrafish retina and through functional expression, we demonstrate that the retina possesses a high degree of connexin diversity, which may account for differential functional properties of electrical synapses. Three new Cxs, designated as zebrafish Cx27.5 (zfCx27.5), zfCx44.1, and zfCx55.5, and the carp ortholog of mammalian Cx43 were cloned. By in situ hybridization and in situ RT-PCR, we demonstrate that the four fish connexin mRNAs show differential localization in the retina. Transient functional expression in paired Xenopus oocytes and in the neuroblastoma N2A cell line indicate an extreme range of electrophysiological properties of these connexins in terms of voltage dependence and unitary conductance. For instance, the new zfCx44.1 exhibited high sensitivity to voltage-induced closure with currents decaying rapidly for transjunctional potentials >10 mV, whereas zfCx55.5 channels showed an opposite voltage dependence in response to voltage steps of either polarity. Moreover, although zfCx44.1 channels showed unitary conductance as high as any previously reported for junctional channels (nearly 300 pS), zfCx55.5 and zfCx27.5 exhibited much lower unitary conductances (<60 pS).link_to_subscribed_fulltex

A multi centre prospective longitudinal study evaluating health related quality of life after immediate Latissimus dorsi (LD) breast reconstruction

Introduction: NICE recommends that the majority of women should be offered immediate breast reconstruction with its potential to improve health related quality of life (HRQL). There is conflicting evidence with a lack of ‘hard’data to best inform clinicians and their patients. Our aim was to evaluate the effects of implant-assisted LD (LDI) versus autologous LD (ALD) breast reconstruction on HRQL over 12 months. Methods: A prospective longitudinal multicentre study commenced in early 2007. Patient reported outcome measures using the EORTC C30 (general HRQL), BR-23 (breast + arm symptoms), Body Image Scale (BIS) and HADS, were completed pre-operatively and at 3, and 12 months after surgery. Longitudinal analyses tested the effects of treatment variables, baseline HRQL, age and time on QL domains (3–12 months). Significance was set at p = 0.01. Results: One hundred and seventy one patients (93 ALD, 78 LDI) were recruited. There were no significant differences in HRQL domains between LDI and ALD (±RT). Chemotherapy patients reported poorer overall HRQL (p &lt; 0.001), poorer role (p = 0.003) and social (p = 0.01) functioning, and greater fatigue (p = 0.002) and depression (p = 0.01). Older patients had fewer HRQL issues (p = 0.01). Significant improvements over time were seen for overall HRQL and other domains (p &lt; 0.001). There were no significant differences between LDI and ALD for patient satisfaction with surgical outcome. Good satisfaction with overall breast appearance and surgical outcome was significantly associated with fewer body image concerns. Conclusion: There is an important need for cumulative clinical evidence in this field on which to base patient informed consent and clinical recommendations