The learning curve for EUS-guided FNA of pancreatic cancer

BACKGROUND: EUS-guided FNA is an effective and safe method for tissue diagnosis of pancreatic cancer. However, EUS-guided FNA is technically challenging and requires special training. The number of cases required to become proficient and the technical steps required to achieve proficiency are unknown. METHODS: The first 57 EUS-guided FNAs of pancreatic masses by a trained endosonographer were analyzed retrospectively. For 50 masses, the histopathologic diagnosis ultimately was cancer. The sensitivity for the EUS-guided FNA diagnosis of adenocarcinoma was compared in quintiles of 10 procedures. RESULTS: Sensitivity for the diagnosis of pancreatic cancer from first to last quintile were, respectively, 50%, 40%, 70%, 90%, and 80%. There was a significant increase in sensitivity for the first 30 cases after improvement in specific technical skills: shortening of echoendoscope position, scrupulous maintenance of the US view of the needle tip at all times, swift jabbing punctures, sampling multiple areas of the mass in each pass, and performing more than 10 "jiggles" per needle pass. Sensitivity for the diagnosis of pancreatic cancer was greater than 80% for the last 20 of the 57 cases, a level that was maintained for cases 51 through 80. CONCLUSIONS: The current American Society for Gastrointestinal Endoscopy guideline of 25 supervised EUS-FNA procedures for the diagnosis of pancreatic adenocarcinoma is reasonable.     

Causes and Types of Precocious Puberty in North-West Iran

Objective

Precocious puberty is of concern because of the underlying disorders, the short adult stature, and the psychosocial difficulties. This study was carried out in order to evaluate the characteristics of children referred to pediatric endocrinology clinic with diagnosis of precocious puberty.

Methods

In a cross-sectional study between February 2007 and September 2009, all of the children referred to pediatric endocrinology clinic in North-West Iran with diagnosis of precocious puberty were recruited.

Findings

Data of 106 girls (82.2%) and 23 boys (17.8%) were analyzed. Mean age of the patients at the time of referral was 6.6±2.8 years (ranging 0.3-14 yr), which was 7±3.9 (ranging 0.3-14 yr) for boys and 6.6±2.5 (ranging 0.8-12 yr) for girls (P=0.6). Out of 129 subjects, 56(43.4%) had precocious puberty, 71.4% (35 cases) of them were due to central precocious puberty and 28.6% (16 cases) were pseudo-precocious puberty. 73 out of 129 subjects (56.6%) were due to normal variants of puberty, normal puberty, and no puberty. 87.5% of subjects with central precocious puberty were idiopathic.

Conclusion

Most of children referred with diagnosis of precocious puberty have benign normal variants. Most of cases with precocious puberty are affected with central precocious puberty, especially with idiopathic form of it.     

RegIIA: an α4/7-conotoxin from the venom of Conus regius that potently blocks α3β4 nAChRs

Neuronal nicotinic acetylcholine receptors (nAChRs) play pivotal roles in the central and peripheral nervous systems. They are implicated in disease states such as Parkinson's disease and schizophrenia, as well as addictive processes for nicotine and other drugs of abuse. Modulation of specific nAChRs is essential to understand their role in the CNS. α-Conotoxins, disulfide-constrained peptides isolated from the venom of cone snails, potently inhibit nAChRs. Their selectivity varies markedly depending upon the specific nAChR subtype/α-conotoxin pair under consideration. Thus, α-conotoxins are excellent probes to evaluate the functional roles of nAChRs subtypes. We isolated an α4/7-conotoxin (RegIIA) from the venom of Conus regius. Its sequence was determined by Edman degradation and confirmed by sequencing the cDNA of the protein precursor. RegIIA was synthesized using solid phase methods and native and synthetic RegIIA were functionally tested using two-electrode voltage clamp recording on nAChRs expressed in Xenopus laevis oocytes. RegIIA is among the most potent antagonist of the α3β4 nAChRs found to date and is also active at α3β2 and α7 nAChRs. The 3D structure of RegIIA reveals the typical folding of most α4/7-conotoxins. Thus, while structurally related to other α4/7 conotoxins, RegIIA has an exquisite balance of shape, charge, and polarity exposed in its structure to potently block the α3β4 nAChRs.     

Normal range determination of lymphocytes subsets in normal adults in Iran

Immunophenotyping of lymphocytes is very essential for evaluation of immune system. Due to the effect of environmental factors and ethical diversity on immune system, establishment of an internal normal range of lymphocyte subsets is a necessity for each population. The aim of this study was to determine the normal range of T and B lymphocytes, and NK cells in normal Iranian adults. Two hundred and thirty three Iranian normal adult volunteers took part in this study. Complete Blood Count (CBC) was performed for them with Sysmex (KX21) and cells with CD3, CD4, CD8, CD19 and CD16/56 surface markers were simultaneously detected by flow cytometry method with FACstar system. Their percentile and absolute count were determined.The volunteers were 150 male and 83 female. Mean percentages of lymphocyte subpopulation were: CD3 (67.66 ±7.76), CD19 (14.41±5.09), CD4 (39.22±6.7), CD8 (25.42 ±5.4) and CD16/56 (10.14±6.42). Also, their mean absolute count of lymphocyte bearing CD3, CD19, CD4 and CD8 were 1,504±505/μl, 332±186/μl, 827±313/μl and 522±185/μl, respectively.Our results are comparable with similar Asian results from other Asian population, but are different from European population, we therefore conclude that it is necessary for each laboratory to establish an internal normal range for the lymphocytes bearing above- mentioned markers.