Two novel AIRE mutations in autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) among Indians

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare recessive disorder resulting from mutations in the autoimmune regulator ( AIRE ) gene. There is no information on AIRE mutations in Indians. In a cross-sectional study, nine patients (eight families), from four referral hospitals in India, were studied for AIRE mutations by direct sequencing. We screened for new mutations in 150 controls by allele-specific PCR. The patients had 1–7 known components of APECED. Three patients had unusual manifestations: presentation with type 1 diabetes; chronic sinusitis and otitis media; and facial dysmorphism. All patients carried homozygous, probably recessive, AIRE mutations. Two unrelated patients from a small in-bred community (Vanika Vaisya) in south India carried an unreported missense mutation, p.V80G, in the N-terminal caspase recruitment domain. Another unique mutation, p.C302X, resulting in a truncated protein with deletion of both zinc-finger domains, was detected in a patient from Gujarat. Neither mutation was detected in controls. Other mutations, previously described in Caucasians, were: 13 base pair deletion (p.C322fsX372) in 4 (38%), and Finn-major (p.R257X) and p.R139X (Sardinian) mutation in one subject each. In conclusion, in this first series of APECED in Indians, we detected AIRE mutations previously reported in Caucasians, as well as unique mutations. Of these, p.V80G is possibly an ancestral mutation in an in-bred community.     

High throughput parallel analysis of hundreds of patient samples for more than 100 mutations in multiple disease genes

As more mutations are identified in genes of known sequence, there is a crucial need in the areas of medical genetics and genome analysis for rapid, accurate and cost-effective methods of mutation detection. We have developed a multiplex allele-specific diagnostic assay (MASDA) for analysis of large numbers of samples (> 500) simultaneously for a large number of known mutations (> 100) in a single assay. MASDA utilizes oligonucleotide hybridization to interrogate DNA sequences. Multiplex DNA samples are immobilized on a solid support and a single hybridization is performed with a pool of allele-specific oligonucleotide (ASO) probes. Any probes complementary to specific mutations present in a given sample are in effect affinity purified from the pool by the target DNA. Sequence-specific band patterns (fingerprints), generated by chemical or enzymatic sequencing of the bound ASO(s), easily identify the specific mutation(s). Using this design, in a single diagnostic assay, we tested samples for 66 cystic fibrosis (CF) mutations, 14 beta-thalassemia mutations, two sickle cell anemia (SCA) mutations, three Tay-Sachs mutations, eight Gaucher mutations, four mutations in Canavan disease, four mutations in Fanconi anemia, and five mutations in BRCA1. Each mutation was correctly identified. Finally, in a blinded study of 106 of these mutations in > 500 patients, all mutations were properly identified. There were no false positives or false negatives. The MASDA assay is capable of detecting point mutations as well as small insertion or deletion mutations. This technology is amenable to automation and is suitable for immediate utilization for high-throughput genetic diagnostics in clinical and research laboratories.      

The advantages of MRI in the detection of occult hip fractures

While the displaced hip fracture can be visualized easily by plain radiography, the non-displaced fracture may be radiographically occult and require different imaging modalities, e.g., MRI for proper visualization. The accuracy of readers and cost advantages of utilizing MRI have not been assessed. Therefore, we undertook a study of these factors. The medical records of all patients who had visited the emergency room from June 2002 until May 2003 with a clinically suspected hip fracture, negative or equivocal plain film and subsequent MRI examination were retrospectively reviewed. Two senior and two junior radiologists independently evaluated both the MR images and radiographs of all 33 patients in a blinded study. One of three possible evaluations was described for the images of each modality: absence, presence or possibility of fracture. The economic consequences of using MRI in the detection of occult hip fractures were calculated. For all four doctors participating in this study, MRI proved to be far more sensitive and specific in the detection of occult hip fractures than radiography. Using the MR images, the senior radiologists identified the occult hip fracture patients with 100% accuracy and were in complete agreement. The agreement between junior and senior radiologists was high (average =0.75). MRI also detected soft tissue injuries in 39% of the patients that could not be identified with radiography. Adoption of the new protocol using MRI saves hospitals from €242 to 627 per patient. By shortening the time to diagnosis and permitting a superior visualization of both bone and soft tissue injuries, MR imaging prevents unnecessary hospitalization and delays in definitive treatment. MR images should be assessed by senior radiologists.     

电视腹腔镜外科手术在胃肠道肿瘤的临床应用

目的探讨腹腔镜外科技术在胃肠道肿瘤手术中的应用。方法经电视腹腔镜行胃肠道肿瘤手术１８例,其中右半结肠切除术４例,横结肠癌根治术３例,乙状结肠癌根治术５例,乙状结肠癌姑息切除术并肝转移癌电凝固化１例,胃癌术后复发转移行探查活检１例,胃巨大恶性淋巴瘤行探查活检１例,晚期回肠癌行小肠侧侧吻合术１例,乙状结肠腺瘤切除术２例。结果均获成功,无中转开腹,手术时间平均１６５．０分钟。术后平均３１．２小时胃肠功能恢复,无并发症发生,术后平均住院８．２天。１３例切除肿瘤的结肠癌术后随访２月～３０月,仅１例横结肠癌术后２３月出现肺转移。结论腹腔镜胃肠肿瘤手术损伤小、恢复快、胃肠干扰小、术后疼痛轻,值得进一步探索开展。