Clinical intraocular islet transplantation is not a number issue

It is now well established that beta cell replacement through pancreatic islet transplantation results in significant improvement in the quality-of-life of type 1 diabetes (T1D) patients. This is achieved through improved control and prevention of severe drops in blood sugar levels. Islet transplant therapy is on the verge of becoming standard-of-care in the USA. Yet, as with other established transplantation therapies, there remain hurdles to overcome to bring islet transplantation to full fruition as a long-lasting therapy of T1D. One of these hurdles is establishing reliable new sites, other than the liver, where durable efficacy and survival of transplanted islets can be achieved. In this article, we discuss the anterior chamber of the eye as a new site for clinical islet transplantation in the treatment of T1D. We specifically focus on the common conceptions, and preconceptions, on the requirements of islet mass, and whether or not the anterior chamber can accommodate sufficient islets to achieve meaningful efficacy and significant impact on hyperglycemia in clinical application.

[Cluster headache in pediatric population: four case reports and review of the literature]

INTRODUCTION

Cluster headache is a rare cause of primary headache in children. We report four cases with a mean age of onset of 8.6, ranged from 2 to 13 years.

CASE REPORTS

Three males and one female with onset at 2, 7, 13, and 12 years-old, respectively, were included. The symptoms of all patients fulfill the criteria for the diagnosis of cluster headache according to the International Society of Headache.

CONCLUSIONS

Despite being rare during childhood, cluster headache should be part of the differential diagnosis of headache in childhood. This report highlights the variable features of this disorder in children, often misdiagnosed. It can be useful in making a quick diagnosis and starting the appropriate treatment early. Verapamil was more effective than flunarizine in terminating the headache in our patients. Oxygen treatment and triptans resulted the treatments with the best response in acute cluster headache.

The anterior chamber of the eye as a clinical transplantation site for the treatment of diabetes: a study in a baboon model of diabetes

AIMS/HYPOTHESIS

The aim of this study was to provide evidence that the anterior chamber of the eye serves as a novel clinical islet implantation site.

METHODS

In a preclinical model, allogeneic pancreatic islets were transplanted into the anterior chamber of the eye of a baboon model for diabetes, and metabolic and ophthalmological outcomes were assessed.

RESULTS

Islets readily engrafted on the iris and there was a decrease in exogenous insulin requirements due to insulin secretion from the intraocular grafts. No major adverse effects on eye structure and function could be observed during the transplantation period.

CONCLUSIONS/INTERPRETATION

Our study demonstrates the long-term survival and function of allogeneic islets after transplantation into the anterior chamber of the eye. The safety and simplicity of this procedure provides support for further studies aimed at translating this technology into the clinic.

Status epilepticus with neuron-reactive serum antibodies: response to plasma exchange

The authors report a patient with partial and secondarily generalized status epilepticus who required 70 days of general anesthesia for seizure control. Although antiepileptic medications failed to control the seizures, they resolved with plasma exchange. The patient's serum reacted with rat cerebral cortex, hippocampus, and cerebellum, but not with cells expressing the glutamate receptor GluR3. These findings suggest an immune response against neuronal antigens other than GluR3.

Capillary isoelectric focusing

Capillary isoelectric focusing (CIEF) provides excellent resolution of proteins with the advantage that separations are carried out in a capillary format with on-tube detection and automated analysis. Recent advances in the technique provide improved resolution, reproducibility and reliability. This review summarizes improvements in sample preparation, capillary selection, and focusing and zone mobilization procedures which have helped CIEF become a more robust analytical method. New applications are reviewed, in particular the use of CIEF in analysis of biopharmaceutical products.

Capillary isoelectric focusing

Capillary isoelectric focusing is a useful analytical technique for characterization of protein mixtures and determination of protein isoelectric points. It is particularly useful in separation of protein glycoforms (Fig. 5), characterizing protein microheterogeneity (Fig. 6), and resolution of charge variants (Fig. 7). The capillary focusing process is analogous to conventional isoelectric focusing in gels, while the requirement for zone mobilization is unique to the capillary format with on-tube detection. A variety of mobilization methods have been described, and the selection of the mobilization method for a particular application depends on the capillary type, the instrument configuration, and the type of proteins to be analyzed. Capillary IEF is generally successful for proteins with a molecular weight up to about 150,000 that exhibit good solubility in aqueous buffers, but may be unsatisfactory for large or hydrophobic proteins. Because of precipitation and variation in mobilization efficiencies, use of internal standards is recommended in most applications. Capillary IEF can be compared to conventional gel IEF in terms of sample throughput and sensitivity. Conventional gels require approximately 4-6 hr to cast, run, and stain the gel, depending on whether silver or Coomassie staining is used. A typical gel contains 10 sample lanes, yielding a throughput of 25-35 min/sample. Capillary IEF separations (including focusing and mobilization) are typically 15-20 min. The mass sensitivity of conventional gel IEF is 36-47 ng for Coomassie staining and 0.5-1.2 ng for silver staining. In capillary IEF, sensitivity will depend on the volume of sample injected; assuming a capillary with a volume of 100 nl is completely filled with sample prior to focusing, the limit of detection will be approximately 1 microgram/ml or 0.1 ng injected. Thus capillary IEF compares favorably with conventional gel IEF in terms of detectivity and analysis time, and has the additional benefit of complete automation of the process including separation and data reduction.