Myotonia in DNM2-related centronuclear myopathy

Centronuclear myopathy (CNM) is a rare hereditary myopathy characterized by centrally located muscle fiber nuclei. Mutations in the dynamin 2 (DNM2) gene are estimated to account for about 50 % of CNM cases. Electromyographic recordings in CNM may show myopathic motor unit potentials without spontaneous activity at rest. Myotonic discharges, a distinctive electrical activity caused by membrane hyperexcitability, are characteristic of certain neuromuscular disorders. Such activity has been reported in only one CNM case without a known genetic cause. We sequenced the DNM2 gene and the genes associated with myotonia (CLCN1, SCN4A, DMPK and ZNF9) in a sporadic adult patient with CNM and myotonic discharges. Sequencing the entire coding region and exon–intron boundaries revealed a heterozygous c.1106g-a substitution in exon 8, resulting in a R369Q change in the DNM2. Sequencing the CLCN1, SCN4A, DMPK and ZNF9 genes ruled out mutations in these genes. This is the first report of DNM2-related CNM presenting with myotonia. The diagnosis of CNM should be considered in patients with myotonic discharges of an unknown cause.     

Outcomes of Laparoscopic Sleeve Gastrectomy in Patients Older than 60 Years

Background

Morbidity and mortality following laparoscopic sleeve gastrectomy (LSG) occur at acceptable rates, but its safety and efficacy in the elderly are unknown.

Methods

A retrospective review was performed of all patients aged >60 years who underwent LSG from 2008 to 2012. These patients were 1:2 matched, by gender and body mass index (BMI) to young patients, 18?<?age?<?50. Data analyzed included demographics, preoperative and postoperative BMI, postoperative complications, and improvement or resolution of obesity-related comorbidities.

Results

Fifty-two morbid obese patients older than 60 years underwent LSG (mean age, 62.9?±?0.3 years). These were matched to 104 young patients, age 18–50 years (mean age, 35.7?±?0.8 years). Groups did not differ in male gender (44 vs. 43 %, p?=?0.9), preoperative BMI (42.6?±?0.7 vs. 42.6?±?0.6, p?=?0.97), and length of follow-up (17?±?2 vs. 22?±?1.4 months, p?=?0.06). Obesity-related comorbidities were significantly higher in the older group (96 vs. 65 %, p?<?0.001). Excess weight loss (EWL) was higher in the younger group (75?±?2.4 vs. 62?±?3 %, p?=?0.001). Older patients had a significantly higher rate of a concurrent hiatal hernia repair (23 vs. 1.9 %, p?<?0.001). Overall postoperative minor complication rate was higher in the older group (25 vs. 4.8 %, p?<?0.001). This included atrial fibrillation (9.5 %), urinary tract infection (7 %), trocar site hernia (4 %), dysphagia, surgical site infection, bleeding, bowel obstruction, colitis, and nutritional deficiency (2 %, each). No perioperative mortality occurred. Comorbidity resolution or improvement was comparable between groups (88 vs. 80 %, p?=?0.13).

Conclusions

LSG is safe and very efficient in patients aged >60, despite higher rates of perioperative comorbidities.     

Characterization and Epitope Mapping of the Polyclonal Antibody Repertoire Elicited by Ricin Holotoxin-Based Vaccination

Ricin, one of the most potent and lethal toxins known, is classified by the Centers for Disease Control and Prevention (CDC) as a select agent. Currently, there is no available antidote against ricin exposure, and the most promising therapy is based on neutralizing antibodies elicited by active vaccination or that are given passively. The aim of this study was to characterize the repertoire of anti-ricin antibodies generated in rabbits immunized with ricin toxoid. These anti-ricin antibodies exhibit an exceptionally high avidity (thiocyanate-based avidity index, 9 M) toward ricin and an apparent affinity of 1 nM. Utilizing a novel tissue culture-based assay that enables the determination of ricin activity within a short time period, we found that the anti-ricin antibodies also possess a very high neutralizing titer. In line with these findings, these antibodies conferred mice with full protection against pulmonary ricinosis when administered as a passive vaccination. Epitope mapping analysis using phage display random peptide libraries revealed that the polyclonal serum contains four immunodominant epitopes, three of which are located on the A subunit and one on the B subunit of ricin. Only two of the four epitopes were found to have a significant role in ricin neutralization. To the best of our knowledge, this is the first work that characterizes these immunological aspects of the polyclonal response to ricin holotoxin-based vaccination. These findings provide useful information and a possible strategy for the development and design of an improved ricin holotoxin-based vaccine.     

Extent and consequences of inadequate disease control among adults with a history of moderate to severe atopic dermatitis

Since control of atopic dermatitis (AD) remains challenging but has not been adequately characterized, the objective of this study was to characterize disease control among patients with a history of moderate to severe AD. Data were from the 2014 Adelphi US AD Disease Specific Programme, a cross‐sectional survey of physicians (n = 202) and their patients with history of moderate to severe AD (n = 1064, 54% female, 75% white, mean age 40 years). Inadequately controlled AD as rated by the physician was defined as currently flaring; deteriorating/changeable AD; or physician dissatisfaction with current control. The overall inadequate control rate was 58.7% (n = 625), which increased with current AD severity and was observed in 53.4% and 83.4% of patients receiving immunosuppressants and systemic corticosteroids, respectively. Relative to controls, inadequately controlled patients had poorer disease‐specific quality of life, higher level of work impairment, greater itch and sleep interference with daily living (all P < 0.05). Multivariate analysis showed factors significantly associated with inadequate control (all P < 0.05), including Hispanic race, symptoms on the head/neck or lower limbs, itch and sleep interference with daily living. A limitation of the study was reliance on accuracy of reporting, potential selection bias and cross‐sectional study design. In summary, there was a high rate and substantial impact of physician‐rated inadequately controlled disease among patients with a history of moderate to severe AD, suggesting the need for more effective therapies.     

Collective cell migration of the nephric duct requires FGF signaling

Background : During the course of development, the vertebrate nephric duct (ND) extends and migrates from the place of its initial formation, adjacent to the anterior somites, until it inserts into the bladder or cloaca in the posterior region of the embryo. The molecular mechanisms that guide ND migration are poorly understood. Results : A novel Gata3‐enhancer‐Gfp‐based chick embryo live imaging system was developed that permits documentation of ND migration at the individual cell level for the first time. FGF Receptors and FGF response genes are expressed in the ND, and FGF ligands are expressed in surrounding tissues. FGF receptor inhibition blocked nephric duct migration. Individual inhibitors of the Erk, p38, or Jnk pathways did not affect duct migration, but inhibition of all three pathways together did inhibit migration of the duct. A localized source of FGF8 placed adjacent to the nephric duct did not affect the duct migration path. Conclusions : FGF signaling acts as a “motor” that is required for duct migration, but other signals are needed to determine the directionality of the duct migration pathway. Developmental Dynamics 244:157–167, 2015. © 2014 Wiley Periodicals, Inc.     

Chloroquine sensitizes biofilms of Candida albicans to antifungal azoles

Biofilms formed by Candida albicans, a human pathogen, are known to be resistant to different antifungal agents. Novel strategies to combat the biofilm associated Candida infections like multiple drug therapy are being explored. In this study, potential of chloroquine to be a partner drug in combination with four antifungal agents, namely fluconazole, voriconazole, amphotericin B, and caspofungin, was explored against biofilms of C. albicans. Activity of various concentrations of chloroquine in combination with a particular antifungal drug was analyzed in a checkerboard format. Growth of biofilm in presence of drugs was analyzed by XTT-assay, in terms of relative metabolic activity compared to that of drug free control. Results obtained by XTT-metabolic assay were confirmed by scanning electron microscopy. The interactions between chloroquine and four antifungal drugs were determined by calculating fractional inhibitory concentration indices. Azole resistance in biofilms was reverted significantly (p < 0.05) in presence of 250 μg/mL of chloroquine, which resulted in inhibition of biofilms at very low concentrations of antifungal drugs. No significant alteration in the sensitivity of biofilms to caspofungin and amphotericin B was evident in combination with chloroquine. This study for the first time indicates that chloroquine potentiates anti-biofilm activity of fluconazole and voriconazole.     

Mucormycosis infection following intravenous access in the forearm

Mucormycosis is an opportunistic infection that is often fatal, requiring aggressive local control as well as systemic therapy. A rare case of a forearm infection originating in a traumatic intravenous access portal is described in the present study. The Mucor species infection prevented liver transplant, and the patient passed away. In the present case, it was decided to limit the resection to the skin and subcutaneous tissue based on a frozen section and the viability of the biopsied tissue. With consistently rising numbers of immunocompromised patients, awareness and familiarity with mucormycosis in the extremities is important. Knowing that a minimal traumatic event may precede the infection could assist in prevention and early diagnosis. Guidelines for pathological and clinical diagnosis and treatment need to be further clarified.