Immunomodulation in type 1 diabetes by NBI-6024, an altered peptide ligand of the insulin B epitope.

NBI-6024 is an altered peptide ligand (APL) corresponding to the 9-23 amino acid region of the insulin B chain (B(9-23)), an epitope recognized by inflammatory interferon-gamma-producing T helper (Th)1 lymphocytes in type 1 diabetic patients. Immunomodulatory effects of NBI-6024 administration in recent-onset diabetic patients in a phase I clinical trial (NBI-6024-0003) were measured in peripheral blood mononuclear cells using the enzyme-linked immunosorbent spot assay. Analysis of the mean magnitude of cytokine responses to B(9-23) and NBI-6024 for each cohort showed significant increases in interleukin-5 responses (a Th2 regulatory phenotype) in cohorts that received APL relative to those receiving placebo. A responder analysis showed that Th1 responses to B(9-23) and NBI-6024 were observed almost exclusively in the placebo-treated diabetic population but not in nondiabetic control subjects and that APL administration (five biweekly subcutaneous injections) significantly and dose-dependently reduced the percentage of patients with these Th1 responses. The results of this phase I clinical study strongly suggest that NBI-6024 treatment shifted the Th1 pathogenic responses in recent-onset type 1 diabetic patients to a protective Th2 regulatory phenotype. The significance of these findings on the clinical outcome of disease is currently under investigation in a phase II multidose study.

Iodine-131 treatment of thyroid papillary carcinoma in patients undergoing dialysis for chronic renal failure: a dosimetric method.

Until recently, the therapeutic protocol widely accepted for ablation of the thyroid remnant and for metastases of thyroid papillary carcinoma was the administration of 131I after surgery. However, at present, some data question the usefulness of such treatment in patients considered low risk. The treatment with radioiodine in patients suffering from end-stage renal disease (ESRD) undergoing hemodialysis requires controlled dosages and individualized administration guidelines. The need to include these patients on the waiting list for a renal transplantation, once they have overcome the disease, and the higher prevalence of thyroid carcinoma in ESRD patients makes this an increasingly significant problem. The cases reported in the literature are few and the therapeutic models followed are very difficult. In this paper we propose a therapeutic model that provides the highest thyroid ablative dosage, minimizing radiation exposure to the rest of the organs. The main difference between our protocol and that already described is the performance of daily hemodialysis during the first 5 days of treatment, as well as the administration of a dose of 131I equivalent to that administered to patients who show normal renal function.

Population structure and ecology of a tropical rare rhizomatous species of teosinte Zea diploperennis (Gramineae).

One of the objectives of the Sierra de Manantlán Biosphere Reserve (Jalisco, México) is the conservation in situ of the teosinte Zea diploperennis Iltis, Doebley, Guzman & Pazzi. Zea diploperennis is perennial, shade intolerant and its 1-3 m shoots are architecturally similar to maize. Clonal growth is of the phalanx type. Genets are iteroparous (modules semelparous). The demography of seven module and genet populations was studied in seven sites representing three stages of old-field succession. Seven permanent one-meter-square plots were randomly established in each site. All genets initially present and those that became established during our study were mapped and labeled according to year of establishment. The magnitude of demographic fluctuations was greater in module populations. Genet population dynamics followed a seasonal rhythm with a maximum population size obtained at the onset of the rainy season. A relation was documented between percent annual mortality of a cohort and its age: the younger the cohort, the greater the mortality. This was a statistically significant relationship, Y = [sin(-0.288x + 1.657)]2 (r = 0.92, p < 0.01), where is proportion annual mortality of genets and is the age of the cohort. The maximum rates of genet mortality occurred during the rainy season when population densities were greatest. As a consequence, we postulate that competition occurs principally during the rainy season. Linear relationships were observed between rate of population increase of genets versus old-field successional stage and soil type. Those areas with poor soil (Ultisol), degraded soil or soils with similar physical characteristics could be rehabilitated by introducing Z. diploperennis. Such rehabilitation would achieve two distinct objectives, promote propagation of this rare endemic and reclaim areas that are susceptible to erosion and further degradation.