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991.
992.
Papillary thyroid carcinoma (PTC) is a common endocrine malignancy, frequently presenting with lymph node metastasis at the time of diagnosis. Lymph node staging (N) partly determines treatment, follow-up, and prognosis. Since 2011, our institution has employed a more comprehensive histopathological work-up of lymph nodes in patients with PTC. We sought to retrospectively determine the value of serial lymph node level sectioning in PTCs with negative preoperative lymph node status (pN0) as a method to increase the sensitivity of detecting metastatic disease. We included all patients that underwent thyroidectomy and central neck dissection and subsequent comprehensive lymph node level sectioning due to PTC with an initial pN0 status between the years 2011 and 2015 at our institution. Sixty-seven cases of PTC with a median of 10 metastatic free lymph nodes identified per case were included. After serial lymph node sectioning of the central compartment, 11 cases (16 %) revealed lymph node metastasis, six of which (55 %) presented with a small primary tumor (<20 mm, T1). Of all T1 tumors with initial pN0 status, 18 % (T1a) and 9 % (T1b) reached a pN1 stage after comprehensive lymph node sectioning. Cases with altered lymph node status had a median of 15 identified lymph nodes as compared to ten in cases that remained negative. We conclude that comprehensive lymph node sectioning increased the sensitivity of detecting metastases in PTC and altered the pathological TNM staging (pTNM) for a significant number of patients. Although of limited prognostic significance, the method should be considered as an adjunct tool when assessing lymph node status of PTC as a part of the routine histological work-up to ensure an accurate cancer staging.  相似文献   
993.
994.
To investigate dental development in patients treated with a hematopoietic stem cell transplantation (HSCT), 42 children and young adults who were under 12 years old at time of HSCT were examined for dental agenesis, microdontia, and root-to-crown ratio. Conditioning regimens were total body irradiation (TBI) based in 12 patients, busulfan based in 21 patients, and 9 patients had other chemotherapeutic agents. Sixteen patients were <3 years old, 9 patients were 3 to 6 years old, and 17 patients were 6 to 12 years old at HSCT. Prevalence of agenesis and microdontia of at least 1 permanent tooth were, respectively, 51.3% and 46.2% in the study population, and 76.3% had an aberrant root-to-crown ratio. All these results were highly different from the prevalence in the healthy population. Patients treated before the age of 3 years had more microdontia (76.9%) and agenesis (92.3%) compared with patients treated at an older age. In the subgroup of patients treated after 6 years, there was more microdontia when treated with busulfan (50%) compared with treatment with TBI (0%) (P?=?.044). Patients treated with HSCT had many disturbances in dental development. Age at HSCT and possibly also the conditioning regimen used had an effect on their type and prevalence. Dental follow-up should be incorporated in the multidisciplinary follow-up program of these patients.  相似文献   
995.
The karyotype is a strong independent prognostic factor in myelodysplastic syndromes (MDS). Since the implementation of the new comprehensive cytogenetic scoring system for MDS, chromosome 7 anomalies are no longer generally assigned to poor risk features but are thoroughly separated. However, der(1;7)(q10;p10), hereinafter der(1;7), is merged into the group labeled “any other single” and belongs to the intermediate risk group, just by definition due to lack of adequate clinical data. The aim of our international collaborative was to clarify the “real” prognostic impact of der(1;7) on a homogenous and well‐documented data base. We performed detailed analysis of 63 MDS patients with isolated der(1;7) constituting the largest cohort hitherto reported. Furthermore, clinical data are compared with those of patients with isolated del(7q) and isolated monosomy 7. Median overall survival (OS) of patients with der(1;7) is 26 months (hazard ratio (HR) 0.91 for del(7q) vs der(1;7) and 2.53 for monosomy 7 vs der(1;7)). The der(1;7) is associated with profound thrombocytopenia most probably causing the reduced OS which is in striking contrast to the low risk for AML transformation (HR 3.89 for del(7q) vs der(1;7) and 5.88 for monosomy 7 vs der(1;7)). Molecular karyotyping indicates that der(1;7) is generated in a single step during mitosis and that a chromosomal imbalance rather than a single disrupted gene accounts for malignancy. Thus, the current cytogenetic scoring system assigning isolated der(1;7) to the intermediate risk group is now confirmed by a sufficient data set.  相似文献   
996.
997.
BACKGROUND AND OBJECTIVES: Familial hyperparathyroidism may occur as familial isolated hyperparathyroidism (FIHP) or as part of an inherited syndrome, in particular multiple endocrine neoplasia types 1 and 2A (MEN1, MEN2A) and hyperparathyroidism-jaw tumour (HPT-JT) syndrome. The localization of the genes responsible for these syndromes has enabled genetic screening of families with primary hyperparathyroidism (PHPT) to be carried out. This has important clinical implications in terms of individual follow-up and management. We previously reported a large FIHP family with an increased risk of parathyroid cancer and excluded its linkage to MEN1, MEN2 and PTH genes. Here we re-analysed this family and performed genetic linkage to the HPT-JT locus in chromosome 1q21-q32. Loss of heterozygosity studies of 1q21-q32, 11q13 and X chromosome were also performed. PATIENTS AND DESIGN: We studied 19 family members, aged 6-63 years. High molecular weight DNA was isolated from peripheral blood samples from 17 family members. For the two deceased individuals, DNA was extracted from normal paraffin embedded tissues. MEASUREMENTS: All individuals (except two deceased patients) had serum corrected calcium, inorganic phosphate, intact PTH, prolactin and various pancreatic hormones, measured on fasting blood samples. Twenty microsatellite markers were examined for the 1q21-q32 region, the locus for the HPT-JT gene. Genetic polymorphisms were determined by polymerase chain reaction amplification of genomic DNA and genetic linkage analysis was performed. Loss of heterozygosity studies were performed using paraffin-embedded parathyroid tissues from four affected members. RESULTS: Seven of the eight affected family members included in this study had biochemical evidence of PHPT and surgically proven parathyroid tumours. Indication of linkage of the disease to the HPT-JT locus was demonstrated with a maximum lod score of 2.32 by two-points linkage analysis. Linkage data were supported by multi-point analysis which gave a maximum lod score of 2.7. Meiotic recombinations detected in one affected individual narrowed the region to 26 cM. As a result of the genetic findings, we re-screened the living family members by orthopantomograph and renal ultrasound, and identified two jaw lesions in two gene carriers. One affected family member demonstrated polycystic kidney disease, thus establishing the association between the two conditions. A reduced penetrance of HPT in females was evident, in agreement with our previous study. No allelic deletion was detected in any tumour at 1q21-q32, 11q13 or X chromosome. CONCLUSIONS: This study illustrates the usefulness and importance of genetic studies in familial isolated hyperparathyroidism families. Our clinical and genetic findings indicate that this previously reported familial isolated hyperparathyroidism family has hyperparathyroidism-jaw tumour syndrome.  相似文献   
998.
Antibacterial peptides and proteins are an integral part of the epithelial defense barrier that provides immediate protection against bacterial invasion. In humans, alpha-defensins are mainly bactericidal effectors in circulating granulocytes, beta-defensin-1 is synthesized in epithelial cells, and LL-37 is produced in granulocytes but is also induced in skin epithelia during inflammation. To investigate the importance of these defense effectors in disease, we analyzed bronchoalveolar lavage fluid (BALF) for bactericidal activity. Antibacterial activity was found in BALF material from healthy individuals and sarcoidosis patients, with enhanced activity in BALF from the patients. The activity was present as several antibacterial components, of which we have so far characterized LL-37, lysozyme, alpha-defensins, and antileukoprotease. In addition, the antibacterial peptide LL-37 was located in alveolar macrophages, bronchial epithelial cells, and bronchial glands, suggesting that it has a defensive role in airway mucosa. In conclusion, the airway epithelium is protected by a complex antibacterial defense system. This is activated in sarcoidosis, and may explain why these patients seldom develop severe respiratory tract infections.  相似文献   
999.
An intronic dinucleotide polymorphism in the IFN-gamma gene (IFNG) was used as a marker for testing association with multiple sclerosis (MS). Disease association was analyzed in case-control sets sampled from four geographically separate European populations (Germany, Northern Italy, Sardinia, and Sweden). Only in the Swedish was a weak disease association of the IFNG allele pattern found, mainly due to a higher frequency of IFNG allele I1 in MS patients. No evidence for association was found in the German or Northern Italian populations. These results contrast with the situation in Sardinia. We have recently reported transmission disequilibrium of IFNG allele I2 in Sardinian MS siblings not carrying the predisposing DRB1 *03 or *04 alleles (Ann. Neurol. 44, 841-842, 1998). Further analysis now shows that I2 is significantly more often transmitted to DRB1 *03-/*04- males, than to DRB1 *03-/*04- females. The odds ratio (OR) for IFNG-associated susceptibility to MS in the total Sardinian DRB1*03-/*04- group was 1.88 for I2 heterozygotes but amounted to 8.235 for I2 homozygotes, suggestive of a recessive mode of inheritance. Score test-based statistics pointed to an I2 allele dosage effect acting in susceptibility. Comparison of the IFNG allele frequencies in seven European populations (Northern Finnish, Southern Finnish, Swedish, Danish, German, Italian, and Sardinian) revealed a highly different distribution pattern. We introduced latitude as a score variable in order to test for trend in binomial proportions. This test statistic showed that for both most common alleles, I1 and I2 (compiled allele frequency about 85%), a significant opposite north-to-south trend is seen throughout Europe. This effect is primarily due to the extreme values found in the outlier populations of Finland and Sardinia. Our findings are discussed with respect to recent literature pertinent to the role of the IFNG chromosome region in autoimmune diseases.  相似文献   
1000.
Measurements of bronchial hyper-responsiveness rely on sensitive techniques for measurement of bronchoconstriction, ideally based on tidal breathing. A potentially useful technique is measurement of airway dead space (VDaw), which reflects the volume of the conducting airways. The aim of this study was to evaluate measurements of VDaw with the single breath test for CO2 (SBT-CO2), compared to spirometric measurements, as a method of measuring bronchial response to methacholine challenge. Nineteen healthy adults were studied. Dosimetric methacholine challenge tests were performed on two study days. Forced expirations or the SBT-CO2 were used to assess the response. There were dose-dependent reductions in the spirometric measurements, with a 10 ± 10% reduction from the baseline value of forced expiratory volume at the highest dose of methacholine. There was a dose-dependent reduction from the baseline value of VDaw by 19 ± 9% at the highest dose. There was also a dose-dependent increase in the slope of the alveolar plateau of the SBT-CO2. This study provides support for measurement of VDaw as a means of evaluating bronchial responsiveness after methacholine challenge. In a group of healthy adults, this method shows a greater response but with similar dispersion as measurement of forced expiratory volume after methacholine challenge.  相似文献   
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