Reanalysis of multislice (1)H MRSI in amyotrophic lateral sclerosis.

The goal of this work was to reexamine previously published (1) brain spectroscopy data of abnormal metabolite ratios in amyotrophic lateral sclerosis (ALS). Toward this goal, (1)H MR spectroscopic imaging data from 10 ALS and nine control subjects were reanalyzed using improved data analysis techniques, including automated curve fitting and tissue-volume correction. In the motor cortex of ALS, N-acetyl aspartate (NAA) was 23% (P = 0.004) lower than in controls, and in the posterior internal capsule of ALS choline compounds (Cho) were 20% (P = 0.02) higher. This demonstrates that the metabolite ratio changes in ALS were due to NAA loss in the motor cortex (as expected) and Cho increase in the posterior internal capsule (not expected). Magn Reson Med 45:513-516, 2001.     

Myocardial blood flow and oxygen consumption during isovolemic hemodilution alone and in combination with adenosine-induced controlled hypotension

Recent reports have proposed combining isovolemic hemodilution and controlled hypotension to limit blood loss during surgery. Before such a technique can be considered for clinical use, it must be demonstrated that it does not endanger maintenance of adequate myocardial oxygenation. Accordingly, measurements of left ventricular myocardial blood flow and oxygen consumption were obtained during isovolemic hemodilution alone and in combination with adenosine-induced controlled hypotension in ten pentobarbital-anesthetized, open chest dogs with normal coronary circulation. Hemodilution to a hematocrit of 21.7% was produced by isovolemic exchange of whole blood for 5% dextran. In the presence of hemodilution, adenosine was infused intravenously at a rate sufficient to decrease mean aortic pressure to 51 mm Hg. Myocardial blood flow was measured with radioactive microspheres and used to calculate global left ventricular myocardial oxygen consumption and oxygen supply. Hemodilution alone increased aortic blood flow (+43%) but had no effect on aortic pressure, left atrial pressure, heart rate, or left ventricular dP/dtmax; an increase in myocardial blood flow (+130%) maintained oxygen supply and consumption at the baseline level. Adenosine-induced hypotension during hemodilution decreased heart rate (-35%), left ventricular dP/dt max (-28%), and aortic blood flow (-14%). These systemic responses were accompanied by reduced myocardial oxygen consumption (-29%) and increased myocardial blood flow (+54%) and myocardial oxygen supply (+72%). These latter effects resulted in reduction in the coronary arteriovenous oxygen content difference and in an attendant rise in coronary sinus Po2 (+66%), which are signs of luxuriant myocardial perfusion.(ABSTRACT TRUNCATED AT 250 WORDS)     

X-linked chronic granulomatous disease: correction of NADPH oxidase defect by retrovirus-mediated expression of gp91-phox

Chronic granulomatous disease (CGD) is an inherited immunodeficiency resulting from the inability of an individual's phagocytes to produce superoxide anions because of defective NADPH oxidase. The disease may be treated by bone marrow transplantation and as such is a candidate for somatic gene therapy. Two thirds of patients have defects in an X- linked gene (X-CGD) encoding gp91-phox, the large subunit of the membrane cytochrome b-245 component of NADPH oxidase. Epstein-Barr virus-transformed B-cell lines from patients with CGD provide a model system for the disease. We have used retrovirus-mediated expression of gp91-phox to reconstitute functionally NADPH oxidase activity in B-cell lines from three unrelated patients with X-CGD. The protein is glycosylated and membrane associated, and the reconstituted oxidase is appropriately activated via protein kinase C. The kinetics of superoxide production by such reconstituted cells is similar to that of normal B-cell lines. These data show the potential of gene therapy for this disease.     

Development of decellularized conjunctiva as a substrate for the ex vivo expansion of conjunctival epithelium

This study was performed to develop a method to decellularize human conjunctiva and to characterize the tissue in terms of its deoxyribose nucleic acid (DNA) content, tensile strength, collagen denaturation, basement membrane, extracellular matrix components and its potential to support conjunctival epithelial growth. Human conjunctival tissues were subjected to a decellularization process involving hypotonic detergent and nuclease buffers. Variations in sodium dodecyl sulfate concentration (0.05–0.5%, w/v) were tested to determine the appropriate concentration of detergent buffer. DNA quantification, collagen denaturation, cytotoxicity and tensile strength were investigated. Human conjunctival cell growth by explant culture on the decellularized tissue substrate was assessed after 28 days in culture. Samples were fixed and paraffin embedded for immunohistochemistry including conjunctival epithelial cell markers and extracellular matrix proteins. Conjunctival tissue from 20 eyes of 10 donors (age range 65–92 years) was used. Decellularization of human conjunctiva was achieved to 99% or greater DNA removal (p < 0.001) with absence of nuclear staining. This was reproducible at the lowest concentration of sodium dodecyl sulfate (0.05% w/v). No collagen denaturation (p = 0.74) and no difference in tensile strength parameters was demonstrated following decellularization. No significant difference was noted in the immunolocalization of collagen IV, laminin and fibronectin, or in the appearance of periodic acid–Schiff‐stained basement membranes following decellularization. The decellularized tissue did not exhibit any cytotoxicity and explant culture resulted in the growth of stratified conjunctival epithelium. Allogeneic decellularized human conjunctiva can be successfully decellularized using the described protocol. It represents a novel substrate to support the expansion of conjunctival epithelium for ocular surface cellular replacement therapies. Copyright © 2017 John Wiley & Sons, Ltd.     

Clinical and patho-anatomical factors affecting expansion of thoracic aortic aneurysms

OBJECTIVE—To examine the expansion of aneurysmal aortic segments ( 35 mm) and to assess the impact of clinical and patho-anatomical factors on aneurysm expansion.
DESIGN—87 consecutive patients (mean age 63.6 years, range 22-84 years) were studied using serial (six month intervals) computed tomographic or magnetic resonance imaging to monitor progression of thoracic aortic aneurysms. Aortic diameter was measured at seven predetermined segments and at the site of maximum aortic dilatation (MAX).
RESULTS—780 segment intervals were identified. The median overall aneurysm expansion rate was 1.43 mm/year. This increased exponentially with incremental aortic diameter (p < 0.01) and varied by anatomical segment (p < 0.05). The presence of intraluminal thrombus (p < 0.01) but not dissection or calcification was associated with accelerated growth. Univariate analysis identified thrombus (p < 0.001), previous stroke (p < 0.002), smoking (p < 0.01), and peripheral vascular disease (p < 0.05) as factors associated with accelerated growth in MAX. Dissection, wall calcification, and history of hypertension did not affect expansion. β Blocker treatment was not associated with protection. Multivariate analysis confirmed the positive effect of intraluminal thrombus and previous cerebral ischaemia, and the negative effect of previous aortic surgery on aneurysm growth. These findings translated into a mathematical equation describing exponential aneurysm expansion.
CONCLUSIONS—Aneurysmal thoracic aortic segments expand exponentially according to their initial size and their anatomical position within the aorta. The presence of intraluminal thrombus, atherosclerosis, and smoking history is associated with accelerated growth and may identify a high risk patient group for close surveillance.


Keywords: thoracic aortic aneurysm; expansion rate     

Adoptive T-cell therapy for EBV-associated post-transplant lymphoproliferative disease

Increased understanding of the mechanisms by which T lymphocytes recognize virus and tumor-specific antigens has fueled the use of adoptive immunotherapy for viral and malignant diseases. An ideal candidate for such treatment is Epstein-Barr virus (EBV). EBV-associated post-transplant lymphoproliferative disorder (PTLD) is a serious complication post-solid organ transplant (SOT) or hematopoietic stem cell transplant (HSCT). The disease is essentially the result of suppression of cytotoxic T-cell function and despite various treatment strategies the course may still be fulminant and lethal. Therefore, an adoptive immunotherapeutic approach using ex vivo derived EBV-specific CTL offers a promising solution not only for the treatment but also as prophylaxis for PTLD. The infusion of EBV-CTL has been demonstrated to be safe and effective in allogeneic HSCT recipients and their use post-SOT is being evaluated.     

Disease-modifying effects of edasalonexent,an NF-κB inhibitor,in young boys with Duchenne muscular dystrophy: Results of the MoveDMD phase 2 and open label extension trial

Chronic activation of NF-κB is a key driver of muscle degeneration and suppression of muscle regeneration in Duchenne muscular dystrophy. Edasalonexent (CAT-1004) is an orally-administered novel small molecule that covalently links two bioactive compounds (salicylic acid and docosahexaenoic acid) that inhibit NF-κB. This placebo-controlled, proof-of-concept phase 2 study with open-label extension in boys ≥4-<8 years old with any dystrophin mutation examined the effect of edasalonexent (67 or 100 mg/kg/day) compared to placebo or off-treatment control. Endpoints were safety/tolerability, change from baseline in MRI T₂ relaxation time of lower leg muscles and functional assessment, as well as pharmacodynamics and biomarkers. Treatment was well-tolerated and the majority of adverse events were mild, and most commonly of the gastrointestinal system (primarily diarrhea). There were no serious adverse events in the edasalonexent groups. Edasalonexent 100 mg/kg was associated with slowing of disease progression and preservation of muscle function compared to an off-treatment control period, with decrease in levels of NF-κB-regulated genes and improvements in biomarkers of muscle health and inflammation. These results support investigating edasalonexent in future trials and have informed the design of the edasalonexent phase 3 clinical trial in boys with Duchenne.