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81.
We studied 21 patients, from 18 families, with L-2-hydroxyglutaric aciduria (L-2-HGA), a rare neurometabolic disorder with a homogeneous presentation: progressive neurodegeneration with extrapyramidal and cerebellar signs, seizures, and subcortical leukoencephalopathy. Increased levels of L-2-hydroxyglutaric acid in body fluids proved the diagnosis of L-2-HGA in all 21 patients. We analyzed the L-2-HGA gene (L2HGDH), recently found to be mutated in consanguineous families with L-2-HGA, and identified seven novel mutations in 15 families. Three mutations appeared to be particularly prevalent in this Portuguese panel: a frameshift mutation (c.529delC) was detected in 12 out of 30 mutant alleles (40%), a nonsense mutation (c.208C>T; p.Arg70X) in 7/30 alleles (23%), and a missense mutation (c.293A>G; p.His98Arg) in four out of 30 mutant alleles (13%), suggesting that common origin may exist. Furthermore, two novel missense (c.169G>A; p.Gly57Arg, c.1301A>C; p.His434Pro) and two splice error (c.257-2A>G, c.907-2A>G) mutations were found. All the mutations presumably lead to loss-of-function with no relationship between clinical signs, progression of the disease, levels of L-2-HGA and site of the mutation. In the three remaining families, no pathogenic mutations in the L-2-HGA were found, which suggests either alterations in regulatory regions of the gene or of its intervening sequences, compound heterozygosity for large genomic deletion and, or further genetic heterogeneity.  相似文献   
82.
A persistent finding is that assisted reproductive technology (ART) is associated with compromised birth outcomes, including higher risks for prematurity, low birthweight, and congenital malformations, even among singletons. Over the past decade, our research group, the Massachusetts Outcome Study of Assisted Reproductive Technology (MOSART), has evaluated pregnancy and birth outcomes among three groups of women, those women treated with ART, those with indicators of subfertility but without ART treatment, and fertile women. We have also explored the influence of infertility-related diagnoses on outcomes for women and infants. Over the course of our research, we have changed our perspective from an original focus on ART treatment parameters as the primary cause of excess morbidity to one centered instead on the underlying infertility-related diagnoses. This paper summarizes the research findings from our group that support this change in focus for infertility-based research from a primary emphasis on ART treatment to greater attention to the contribution of preexisting pathology underlying the infertility and suggests directions for future analyses.  相似文献   
83.
The aim of this study was to describe the clinicopathologic features of 177 keratocystic odontogenic tumors (KCOTs) diagnosed in a Brazilian population. A total of 177 KCOTs were reviewed and affected 158 patients with ages ranging from 5 to 79 years (mean age = 32 years) with a slight female predominance. Mandible was the most common affected site (69.3%), and a unilocular radiolucency was the most common radiographic image. Microscopically, all cases showed at least focal areas of classic KCOT, but several histological aspects were also observed, including diffuse and focal epithelial lining hyperplasia (48.6%), epithelial budding (12.4%), reactive cytological alterations (11.3%), dystrophic calcification (7.9%), daughter cysts (7.8%), odontogenic epithelial remnants (4.5%), focal areas of orthokeratinization (2.8%), and ameloblastomatous epithelium (1.7%). These variations may make KCOT diagnosis challenging in some cases, so careful full-sample analysis and knowledge of these uncommon histological features associated with KCOT are essential for correct diagnosis.  相似文献   
84.
The mechanisms underlying the progression from ductal carcinoma in situ (DCIS) to invasive ductal carcinoma (IDC) of the breast are yet to be fully elucidated. Several hypotheses have been put forward to explain the progression from DCIS to IDC, including the selection of a subpopulation of cancer cells with specific genetic aberrations, and the acquisition of new genetic aberrations or non-genetic mechanisms mediated by the tumour microenvironment. To determine whether synchronously diagnosed ipsilateral DCI and IDCs have modal populations with distinct repertoires of gene copy number aberrations and mutations in common oncogenes, matched frozen samples of DCIS and IDC were retrieved from 13 patients and subjected to microarray-based comparative genomic hybridization (aCGH) and Sequenom MassARRAY (Oncocarta v 1.0 panel). Fluorescence in situ hybridization and Sanger sequencing were employed to validate the aCGH and Sequenom findings, respectively. Although the genomic profiles of matched DCI and IDCs were similar, in three of 13 matched pairs amplification of distinct loci (ie 1q41, 2q24.2, 6q22.31, 7q11.21, 8q21.2 and 9p13.3) was either restricted to, or more prevalent in, the modal population of cancer cells of one of the components. Sequenom MassARRAY identified PIK3CA mutations restricted to the DCIS component in two cases, and in a third case the frequency of the PIK3CA mutant allele reduced from 49% in the DCIS to 25% in the IDC component. Despite the genomic similarities between synchronous DCIS and IDC, our data provide strong circumstantial evidence to suggest that in some cases the progression from DCIS to IDC is driven by the selection of non-modal clones that harbour a specific repertoire of genetic aberrations.  相似文献   
85.
目的 观察血清降钙素原(PCT)、C反应蛋白(CRP)及其动力学变化,评估其在严重脓毒症/感染性休克患者的诊断及预后价值.方法 本研究采用回顾性分析方法,2014年9月1日至2016年4月30日选择184例ICU中被诊断为严重脓毒症/感染性休克疾病患者,检测入院时血清PCT、CRP水平和治疗后第2,第3和第5天的PCT、CRP水平.结果 通过△PCT、△CRP评估PCT、CRP的动力学在存活者与死亡组中有显著性统计学意(△PCT2/0,P=0.0001;△PCT3/0,P=0.0001;△PCT5/0,P=0.0001;△CRP2/0,P=0.0069;△CRP3/0,P=0.0001;△CRP5/0,P=0.0001),在严重脓毒症和感染性休克组中也存在显著差异(PCT5,P=0.007;△PCT5/0,P=0.007).受试者工作特征曲线(ROC)模型显示,△PCT3/0(AUC=0.721)、△PCT5/0(AUC=0.77)、△CRP5/0(AUC=0.766)水平判断严重脓毒症/感染性休克患者预后有较好的临床意义.△PCT5/0 (0.619)对严重脓毒症或感染性休克有一定的辅助诊断效果,其在ROC曲线上灵敏度、特异性均较高的临界点为0.624,所以,以第5天的血清△PCT5/0水平>0.624可作为预测感染性休克的临界点.结论 血清中PCT、CRP对严重脓毒症/感染性休克早期有较好的临床诊断及预后价值,其动力学研究可以提高对严重脓毒症/感染性休克诊断及预后评估的敏感性及准确性.  相似文献   
86.
A de novo complex chromosome rearrangement (CCR) involving chromosomes 1, 6, 7, 15 and Y was detected in a boy with mental retardation, short stature, and microcephaly. Fluorescence in situ hybridisation (FISH) with whole chromosome painting libraries, band-specific cosmids and telomeric probes was essential for the characterisation of the rearrangement. The CCR was shown to be the result of at least nine chromosomal breaks and involved the alternating insertion of two segments of the short arm of chromosome 1 and two segments of the long arm of chromosome 6 into a novel derived chromosome 7. A non-reciprocal translocation between the distal short arm of the same chromosome 7 and the distal long arm of the Y chromosome was also found, together with a paracentric inversion of the long arm of chromosome 15. The only detectable imbalance was a deletion of the heterochromatic Yq telomeric region. FISH investigations in this case have revealed an additional complexity in this CCR, which has implications for reproductive risk assessment and genetic counselling.  相似文献   
87.
Blood samples were collected from 487 adult horses, including 83 pregnant mares, at a slaughterhouse located in Araguari, Minas Gerais State, Brazil. For each blood sample, the packed cell volume (PCV) was determined, and Giemsa-stained smears were microscopically examined for the presence of hemoparasites. The plasma was examined by the indirect fluorescent antibody test for detection of antibodies against Babesia caballi and Theileria equi. In addition, DNA was extracted and analyzed by a multiplex real-time polymerase chain reaction (PCR), specific for B. caballi and T. equi. Products of PCR were sequenced and compared with each other and with known sequences. The serological results showed a total prevalence of 91.0% for T. equi and 83.0% for B. caballi, while by PCR, prevalences of 59.7% for T. equi and 12.5% for B. caballi were observed. However, no correlations were seen between positivity (neither by serology nor by PCR) and PCV values. As expected, the microscopic examination of blood smears showed low sensitivity in detecting the infections when compared to the PCR. Only 35 out of 570 blood smears were positive, with parasitemias below 0.1%. No congenital transmission was detectable. As far as sequencing is concerned, no differences were seen among the isolates of each species nor among them and known sequences available. These results confirm, by molecular methods, the high prevalence rates of T. equi and B. caballi infections in carrier horses in Brazil. However, no diversity was observed among the isolates within the studied regions.  相似文献   
88.
The Pacific white shrimp, Litopenaeus vannamei, is the most important shrimp species in volume in world aquaculture. However, in recent decades, outbreaks of diseases, especially viral diseases, have led to significant economic losses, threatening the sustainability of shrimp farming worldwide. In 2004, Brazilian shrimp farming was seriously affected by a new disease caused by the Infectious myonecrosis virus (IMNV). Thus, disease control based on rapid and sensitive pathogen detection methods has become a priority. In this study, a specific quantitation method for IMNV was developed using real-time PCR with SYBR Green chemistry and viral load of the principal target tissues of chronically infected animals was quantified. The quantitative analysis revealed that mean viral load ranged from 5.08 × 108 to 1.33 × 106 copies/μg of total RNA in the hemolymph, 5.096 × 105 to 1.26 × 103 copies/μg in the pleopods, 6.85 × 108 to 3.09 × 104 copies/μg in muscle and 8.15 × 106 to 3.90 × 103 copies/μg in gills. Different viral loads of IMNV were found with greater values in the hemolymph and muscle, followed by the pleopods and gills.  相似文献   
89.
Background: Abnormalities in calcium and vitamin D metabolism are observed early after gastric bypass, whereas clinical or biochemical evidence of metabolic bone disease might not be detected until many years after the procedure. The aim of the present study was to evaluate the impact of bariatric surgery on bone metabolism determined on the basis of postoperative laboratory changes in calcium, phosphorus, magnesium, alkaline phosphatase and parathormone (PTH) levels. Methods: 110 patients submitted to Roux-en-Y gastric bypass (RYGBP) were followed after surgery, and the following parameters were determined: intact PTH molecule (PTHi; chemiluminescence), alkaline phosphatase (colorimetric method), ionic calcium (selective electrode), phosphorus and magnesium (colorimetric method). Results: Elevated serum PTHi levels were observed in 29% of the patients and hypocalcemia in 0.9% from the 3rd postoperative month and afterwards (3 to 80 months after surgery). Conclusion: There is a need for careful evaluation of bone metabolism and for routine calcium replacement after RYGBP.  相似文献   
90.
Tubular carcinoma of the breast is a variant of invasive ductal carcinoma that is well differentiated and characterized by an orderly tubular formation. Although often perceived to have a better prognosis, there continues to be questions regarding the extent of treatment required. A retrospective review of 44 patients diagnosed with tubular carcinoma of the breast from 1987 to 1999 was performed. All documented data regarding patient and tumor characteristics plus the extent of treatment were analyzed and compared. Lymph node metastases were present in 4 of 32 patients (13%) who had nodes examined. Tumor size correlated with axillary status, with tumors less than 15 mm having no axillary nodal involvement. No other factor influenced nodal status. In breast conservation patients without adjuvant radiation, 5% (1 of 20) had local recurrence versus 0% (0 of 13) of patients who received postoperative radiation. Ductal carcinoma in situ (DCIS) was associated with 52% of tubular cancers. Second breast cancers developed in 16% of cases. There was no difference in presentation or outcome for pure versus mixed tubular carcinoma. Overall mortality was 2%. Overall survival for patients with tubular carcinoma is quite good. Breast conservation treatment results in low rates of local recurrence for tubular carcinoma with or without the use of adjuvant radiation therapy. Pure tubular carcinomas had the same behavior and overall prognosis as mixed tubular carcinomas and should be classified together. Lymph node status did not influence disease-free or overall survival.  相似文献   
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