HFE-codon 63/282 (H63D/C282Y) gene variants in Mexican Mestizos are not risk factors for leukemia

BACKGROUND: In some Caucasian populations it has been found that the C282Y hemochromatosis (HFE) gene mutation is a risk factor for the development of leukemia and other malignancies. METHODS: In a group of 50 Mexican mestizo patients and 153 normal controls, the HFE gene mutations H63D and C282Y were studied by means of ARMS-PCR. RESULTS: In the group of patients with leukemia we found a heterozygote for the C282Y mutation, seven heterozygotes for the H63D mutation, a double heterozygote for the H63D / C282Y mutation and 41 normal homozygotes. These data are not different from those observed in normal controls, where the allele frequencies were 0.062 and 0.013 for the H63D and C282Y HFE gene mutations, respectively. CONCLUSIONS: These HFE gene mutations are not risk factors for the development of leukemia in Mexican mestizos.     

Intravenous morphine and topical tetracaine for treatment of pain in [corrected] neonates undergoing central line placement

Context  There is limited evidence of the analgesic effectiveness of opioid analgesia or topical anesthesia during central line placement in neonates, and there are no previous studies of their relative effectiveness. Objective  To determine the effectiveness and safety of topical tetracaine, intravenous morphine, or tetracaine plus morphine for alleviating pain in ventilated neonates during central line placement. Design, Setting, and Participants  Randomized, double-blind, controlled trial enrolling 132 ventilated neonates (mean gestational age, 30.6 [SD, 4.6] weeks at study entry) and conducted between October 2000 and July 2005 in 2 neonatal intensive care units in Toronto, Ontario. Interventions  Prior to central line insertion, neonates were randomly assigned to receive tetracaine (n = 42), morphine (n = 38), or both (n = 31); a separate nonrandomized group of 21 neonates receiving neither tetracaine nor morphine was used as a control group. Main Outcome Measures  The primary outcome measure was a pain score for the proportion of time neonates displayed facial grimacing (brow bulge) during different phases of the procedure (skin preparation, needle puncture, and recovery). In randomized neonates, safety assessments included blood pressure, ventilatory support, and local skin reactions. Results  Compared with no treatment, pain scores were lower in the morphine and tetracaine-morphine groups during skin preparation (mean difference, –0.22; 95% confidence interval [CI], –0.4 to –0.04; P = .02 and –0.29; 95% CI, –0.49 to –0.09; P = .01, respectively), and needle puncture (mean difference, –0.35; 95% CI, –0.57 to –0.13; P = .003 and –0.47; 95% CI, –0.71 to –0.24; P<.001, respectively), but pain scores did not differ statistically for tetracaine alone vs no treatment. Pain scores were lower for morphine and tetracaine-morphine vs tetracaine during the skin preparation phase and for tetracaine-morphine vs tetracaine during needle puncture. Compared with neonates without morphine, morphine-treated neonates required larger increases in ventilation rate in the first 12 hours (mean difference, 3.9/min; 95% CI, 1.3-6.5/min; P = .003). Local skin reactions occurred in 30% of neonates given tetracaine vs 0% for morphine (risk difference, 0.30; 95% CI, 0.19-0.41; P<.001). Conclusion  In this study of ventilated neonates undergoing central line placement, morphine and tetracaine plus morphine provided superior analgesia to tetracaine; however, morphine caused respiratory depression and tetracaine caused erythema. Clinical Trials Registration  ClinicalTrials.gov Identifier: NCT00213200      

Role of beta-galactosidase and elastin binding protein in lysosomal and nonlysosomal complexes of patients with GM1-gangliosidosis

G(M1)-gangliosidosis is a lysosomal storage disorder caused by a deficiency of beta-galactosidase (GLB1). The GLB1 gene gives rise to the GLB1 lysosomal enzyme and to the elastin binding protein (EBP), involved in elastic fiber deposition. GLB1 forms a complex with protective protein cathepsin A (PPCA), alpha neuraminidase (NEU1), and galactosamine 6-sulphate sulfatase (GALNS) inside lysosomes, while EBP binds to PPCA and NEU1 on the cell surface. We investigated the function of the GLB1 and EBP mutated proteins by analyzing the clinical, genetic, and cellular data of 11 G(M1)-gangliosidosis patients. Their molecular analysis, followed by expression studies, lead to the identification of four new and 10 known GLB1 mutations. Some common amino acid substitutions [c.1445G>A (p.Arg482H), c.622C>T (p.Arg208His), c.175C>T (p.Arg59Cys) and c.176G>A (p.Arg59His)] were present in the GLB1 enzyme of several patients, all of Mediterranean origin, suggesting a common origin. Western blotting analyses against GLB1, EBP, and PPCA proteins showed that the identified mutations affect GLB1 enzyme activity and/or stability. The c.1445G>A (p.Arg482His), c.175C>T (p.Arg59Cys), c.733+2T>C, c.1736G>A (p.Gly579Asp), and c.1051C>T (p.Arg351X) GLB1 mutations, affect the stabilization of PPCA probably because they hamper the interaction between GLB1/EBP and PPCA within the multiprotein complex. The amount of EBP was normal, but the detection of impaired elastogenesis in such patients suggests an alteration in its function. We conclude that the presence of genetic lesions in both GLB1 and EBP coding region does not directly predict impaired elastogenesis and that elastic fiber assembly has to be evaluated specifically in each case. Nevertheless, the degree of EBP involvement may be linked to specific clinical findings.     

Temporal and spatial expression pattern of beta1 sodium channel subunit during heart development

OBJECTIVES: The aim of this study is to analyze Scn1b mRNA expression levels and protein distribution of Scn1b, a putative modulator of the pore-forming Na(+) channel subunit in the heart, during mouse cardiac development. METHODS: Scn1b mRNA levels were determined by real-time RT-PCR using embryonic hearts ranging from E9.5 to E18.5 as well as in postnatal and adult heart. Scn1b protein distribution and subcellular localization during cardiogenesis were analyzed by immunohistochemistry and confocal microscopy. RESULTS: Scn1b mRNA showed a dynamic expression pattern, peaking at stage E12.5 and decreasing at E15.5. Scn1b mRNA increased at later embryonic and neonatal stages, being maximal in the adult heart. Immunohistochemistry experiments revealed comparable distribution of Scn1b protein between the different cardiac chambers at early embryonic stages. With further development, Scn1b protein showed an enhanced expression in the trabeculated myocardium and the bundle branches. At the subcellular level in later embryonic and postnatal mouse cardiomyocytes, Scn1b was present in T-tubules as identified by immunostaining of alpha-actinin, and in the intercalated disks as identified by immunostaining of connexin 43. CONCLUSION: These results demonstrate that Scn1b is expressed during mouse heart development, suggesting it can play an important role in the action potential configuration of the cardiomyocytes during heart morphogenesis.     

Repeated exposure to pyrrolidine-dithiocarbamate induces peripheral nerve alterations in rats

Pyrrolidine-dithiocarbamate (PDTC), a synthetic compound widely used in cell biological investigations, recently attracted considerable interest as a putative anticancer agent. However, different dithiocarbamates have previously shown to cause neurological symptoms and morphological alterations in peripheral nerves. The purpose of the present study was to determine whether a 15-day oral administration with low doses of PDTC may produce adverse effects in peripheral nerves of rats. Female Wistar rats were assigned to receive PDTC [0.1, 0.5 or 1.0mmol/(kg body weight/day)] by gavage for 15 days. Reduced conduction velocity was observed by electrophysiological analysis in tibial nerves of treated animals, accompanied by a marked decrease in Shwann cell S100-protein expression determined by immunohistochemistry. Electron microscopy evaluation revealed marked myelin degeneration in the fibers of treated animals. In particular, both morphological and electrophysiological data suggested an impairment of large, fast conducting fibers, whereas the smallest and slowest ones remained intact. However, the activity of plasma and liver alkaline-phosphatase, an enzymic marker of hepatic dithiocarbamate toxicity, was not altered by the treatment. The total contents of the redox-active metal copper increased in tibial nerves of treated rats and was accompanied by raised levels of lipid peroxidation products. This finding suggests a role for oxidative stress in the development of PDTC-induced pathological and functional alterations of tibial nerves. The observation that a 15-day treatment with low doses of PDTC causes functional and morphological derangement of peripheral nerves advices against the possible use of this compound as a chemopreventive agent against cancer.     

A prospective evaluation of laparoscopic exploration with intraoperative ultrasound as a technique for localizing sporadic insulinomas

BACKGROUND: Preoperative imaging studies localize insulinomas in less than 50% of patients. Arteriography with calcium stimulation and venous sampling (ASVS) regionalizes greater than 90% of insulinomas but requires specialized expertise and an invasive procedure. This prospective study evaluated laparoscopic exploration with IOUS compared with the other localization procedures in patients with a sporadic insulinoma. METHODS: Between March 2001 and October 2004, 14 patients (7 women and 7 men; mean age, 53) with an insulinoma were enrolled in an IRB-approved protocol. Computed tomography, magnetic resonance imaging, ultrasound scan, and arteriography with calcium stimulation and venous sampling were performed preoperatively. A surgeon, blinded to the results of the localizing studies, performed a laparoscopic exploration with intraoperative ultrasound (IOUS). At the completion of the exploration, the success of laparoscopy for localization was scored, and the tumor was resected. RESULTS: Twelve of 14 tumors were localized successfully before laparoscopy (noninvasive, 7 of 14; invasive, 11 of 14). Laparoscopic IOUS localized successfully 12 of 14 tumors. All lesions were resected, and all patients were cured (median follow-up, 36 months). CONCLUSION: Laparoscopic IOUS identified 86% of tumors. The authors consider laparoscopic IOUS to be equivalent to ASVS in localizing insulinomas. Further study is therefore warranted to determine the role of laparoscopy with IOUS in the localization and treatment algorithm for patients with sporadic insulinoma.     

Applications of the oral scraped (exfoliative) cytology in oral cancer and precancer

Scraped (exfoliative) cytology is a simple and harmless procedure, which has been a controversial technique according to its real validity in oral pathology. Lately it has re-emerged due to its application in oral precancer and cancer as a diagnostic and predictive method as well as for monitoring patients. New diagnostic techniques have been developed, such as "brush biopsy" and multiple molecular studies using the cells collected. In this review we are going to analyse the more novel aspects related with the applications of the scraped or exfoliative cytology in oral precancerous and cancerous pathology, specially focusing on molecular studies and their diagnostic and prognostic implications.     

A survey of interprofessional education in communication skills in health care programmes in the UK

There is considerable evidence to indicate that patient satisfaction is directly related to the communication skills of health care providers. However, communication is an area in which health care practitioners often fail to meet patients' needs. Interprofessional education (IPE) is advocated as one way of improving health care communication for the consequent development of interprofessional care. However, poorly planned and delivered IPE can reinforce professional differences, so it is imperative that its introduction is based upon sound evidence of local need, opportunity and resources. A multidisciplinary and cross university project was designed to identify opportunities for, and best practice in, IPE in communication skills amongst undergraduate health care practitioners within one Workforce Development Directorate (WDD) in England. Methods included a comprehensive literature review of relevant educational initiatives, together with telephone and e-mail interviews with key informants in higher education institutions (HEIs) across the UK. This paper reports the findings from the interviews. Based upon these findings, a series of recommendations are made for the planning, implementation, and evaluation of IPE in communication skills, which should be taken into account by local curriculum planning groups.