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161.
BACKGROUND: Tamoxifen has favorable effects on the serum lipid profile. It has been suggested that the apolipoprotein (Apo) E phenotype can influence serum lipid parameters; the ApoE allele 4 (ApoE4) is associated with higher total and low-density lipoprotein (LDL) cholesterol levels. The ApoE phenotype also affects lipid responses to diets or treatment with statins. However, the effect of tamoxifen on the lipid profile in different ApoE phenotypes is unknown. PATIENTS AND METHODS: In the present study, we evaluated the effects of tamoxifen on the serum lipid profile in 11 ApoE4-positive postmenopausal women with breast cancer (phenotypes 3/4 and 4/4) compared with 33 ApoE4-negative women (phenotypes 3/2 and 3/3). Serum lipid parameters [high-density (HDL), LDL and total cholesterol, triglycerides, ApoAI, ApoB and lipoprotein (a)] were measured after an overnight fast before treatment and after 3 and 12 months. ApoE isoforms were determined by isoelectric focusing of delipidated very-low-density lipoproteins (VLDL). RESULTS: During the follow-up period, serum levels of total and LDL cholesterol and ApoB decreased significantly in both groups, but no significant differences were found. Concentrations of serum HDL cholesterol were not significantly different between both groups. However, serum ApoAI levels increased significantly in ApoE4-negative subjects (p = 0.00005), but no significant changes in ApoE4-positive women were observed. Serum triglyceride levels increased by 23.2% (p < 0.05) in ApoE4-positive patients, but they did not change significantly in ApoE4-negative patients. The LDL/HDL cholesterol ratio decreased similarly in the two groups, but the ApoAI/ApoB ratio, which may be a better predictor of cardiovascular events, significantly changed in the ApoE4-negative subjects. Finally, the median level of Lp(a) decreased by 43.4% in the ApoE4-negative patients, whereas it did not change significantly in the ApoE4-positive group. CONCLUSION: In postmenopausal Greek women with breast cancer, the levels of Lp(a) and triglycerides and the ApoAI/ApoB ratio respond more favorably to tamoxifen treatment in ApoE4-negative than in ApoE4-positive patients.  相似文献   
162.
BACKGROUND: Patients with severe decompensated congestive heart failure (CHF) commonly exhibit acid-base and electrolyte disturbances mainly due to the activation of several neurohumoral mechanisms as well as to drugs regularly used in this population. Magnesium deficit is not infrequently observed in CHF patients but its pathophysiology remains less well-studied as compared with other electrolyte alterations, such as hypokalemia. However, there is evidence that early detection and correction of magnesium abnormalities could obviate potentially deleterious arrhythmogenic effects. AIM: To assess the incidence of magnesium level disorders and analyze the underlying pathophysiological mechanisms in patients with CHF. METHODS: Eighty-six consecutive CHF patients (NYHA class III or IV) admitted to our hospital over a period of 5 years were studied. Patients with diabetes mellitus, liver or renal failure, and chronic obstructive lung disease were excluded. All patients received conventional treatment with digoxin, diuretic agents and an angiotensin converting enzyme inhibitor. On admission, blood and urine electrolytes and renal function parameters were determined. Arterial blood gases and serum anion gap determinations were also performed. RESULTS: Hypomagnesemia was found in 15 [n=15 (17.4%)] CHF patients. The majority of these patients also exhibited other electrolyte abnormalities, such as hypokalemia, hypocalcemia and hypophosphatemia. Inappropriate magnesiuria (fractional excretion of magnesium >4%) was evident in eight hypomagnesemic patients. A variety of associated conditions, including poor dietary intake, also favored magnesium depletion. CONCLUSION: Magnesium deficit is a common electrolyte disorder in CHF (NYHA class III/IV) patients and several interrelated mechanisms are implicated in its pathogenesis. Clinicians' awareness of the incidence of hypomagnesemia in this population as well as its related pathophysiology could be useful for the early detection and appropriate treatment to inhibit its arrhythmogenic potential.  相似文献   
163.
Leuconostoc species, which are members of the family Streptococcacae, have only recently been recognized as potential pathogens. We describe a patient with type II diabetes mellitus who had multiple liver abscesses associated with bacteremia due to Leuconostoc lactis. To our knowledge, this is the first case of this association to be reported in the literature.  相似文献   
164.
Abstract:  The aim of the study was to assess the possible associations between allergies and type 1 diabetes mellitus (DM1), stratified by social class. We studied 127 children with DM1 with a median age of 10.8 yr and 150 controls of comparable age and sex distribution. The parents completed questionnaires on their education and occupation and on their children's history of allergic symptoms, breast-feeding, viral infections, and measles–mumps–rubella (MMR) vaccination. Lower family's social class was more frequently encountered among the DM1 families than in the controls (OR = 0.56, 95% CI: 0.35–0.92). The occurrence of any allergic symptoms among children with DM1 (35.45%) was not significantly different from the controls (38.78%), neither in the total group (OR = 0.87, 95% CI: 0.52–1.45) nor in the stratified analysis by social class. Similar findings were observed regarding the different types of allergic symptoms. In the univariate analysis, breast-feeding, the experience of viral infections, and MMR vaccination were found to be protective of DM1 presentation in both upper and lower social classes. In the multiple logistic regression analysis, the experience of more than 2 infections/yr (OR = 0.12, 95% CI: 0.04–0.34), the origin from middle and upper social classes (OR = 0.42, 95% CI: 0.22–0.80) and breast-feeding (OR = 0.58, 95% CI: 0.31–1.07) were protective of DM1 occurrence. In children with DM1, the presence of allergic symptoms was not associated with the development of DM1. Among the environmental factors, the origin from middle or upper social classes, breast-feeding, the experience of viral infections, and MMR vaccination were found to have a protective effect on DM1 presentation.  相似文献   
165.

Background

Tissue genomic heterogeneity (t-HET) in patients with epithelial ovarian cancer (OVCA) is related to tissue plasticity, i.e., flexibility to adapt to adverse molecular environments. Here, we interrogated the presence and clinical relevance of OVCA t-HET.

Methods

We applied high-depth (>2000×) sequencing on 297 paraffin tissue samples (fallopian tubes, ovaries, intra-abdominal metastases) from 71 treatment-naïve patients who subsequently received first-line platinum-based chemotherapy. Based on tissue mutation patterns, we distinguished tissue genotypes into: no mutation (33/297 samples; 11.1%), stable (173; 58.2%) and unstable (91; 30.7%). We profiled genotypes per patient and assessed t-HET in 69 patients. Predicted pathogenic mutations refer to germline and/or tissues.

Results

Among all 71 patients, 46 (64.8%) had pathogenic BRCA1 mutations and 15 (21.7%) had BRCA1/2 disruption (i.e., pathogenic mutations with position-LOH). We classified 29 patients with t-HET (42%), all with pathogenic BRCA1; t-HET was observed in 64% with such mutations (p?<?0.001). As opposed to non-t-HET, matched tissues in t-HET shared pathogenic BRCA1 (p?<?0.001) but not BRCA2 and TP53. Germline BRCA1 mutations in tissues exhibited position-LOH; heterozygous status; or, partial loss of the inherited allele accompanied by additional clonal mutations. Patients with t-HET had worse outcome (log-rank p?=?0.048 [progression-free]; p?=?0.037 [overall survival]), including 12/15 patients with disrupted BRCA1/2 and 3 BRCA1 carriers with partial germline loss in tissues.

Conclusions

Pathogenic BRCA1 mutations appear necessary but may not be sufficient for the establishment of t-HET. t-HET may be associated with worse outcome, including in patients with disrupted BRCA1/2, which is usually considered as a favourable marker. OVCA t-HET may need to be addressed for treatment decisions.  相似文献   
166.
It has been reported that the cyclin-dependent kinase inhibitor (CDKI) gene p15INK4B is frequently inactivated by genetic alterations and may be responsible for various malignant tumours. Another way of inactivation of this CDKI is by hypermethylation of 5'CpG islands in the promoter region of the p15INK4B gene and this inactivation seems to be a frequent event in various haematological malignancies. In the present study, we investigated the methylation status of the p151NK4B gene to clarify its role in the pathogenesis of childhood acute myeloid (AML) and acute lymphoblastic leukaemia (ALL). The study included 23 cases of B-cell origin ALL, 13 cases of T-cell origin ALL, 32 cases of AML, and 10 apparently healthy controls. Hypermethylation was studied by methylation-specific polymerase chain reaction. Hypermethylation of the p15INK4B gene was more frequent in cases with T-cell origin ALL (46.2%), but similar among children with B-cell origin ALL (13.0%) and AML (18.8%). Hypermethylation of p15INK4B may be involved in the pathogenesis of T-cell origin ALL, but not in that of AML or B-cell origin ALL.  相似文献   
167.
Transcatheter arterial embolization (TACE) is a minimally invasive procedure that requires precise visualization of the feeding vessels to liver tumors for proper catheter placement and effective therapy. The use of three-dimensional (3D) rotational angiography (RA) can be extremely useful to the interventional radiologist during TACE while the patient is on the catheterization table. This report demonstrates the role of 3D RA in interventional oncology by presenting two cases of hepatocellular carcinoma with complex vascular anatomy successfully treated because of the information provided by this new technology.  相似文献   
168.
BACKGROUND: We evaluated the value of coronary artery calcification (CAC) score in coronary artery disease (CAD) detection in asymptomatic hemodialysis (HD) patients by evaluating the association among CAC score, exercise electrocardiography (EECG), and Thallium-201 dipyridamole scintigraphy. Correlation between aortic pulse wave velocity (PWV) and CAC score was also evaluated. METHODS: CAC score was assessed with conventional computed tomography in 40 patients. Thirty patients completed EECG and 25; those with a positive CAC score and/or a positive EECG performed Thallium dipyridamole scintigraphy. Carotid-femoral PWV was assessed in all patients. RESULTS: There was no association among CAC score and EECG or Thallium dipyridamole scintigraphy. In contrast, CAC score was correlated with aortic PWV. CONCLUSION: The previous results question the role of CAC score in the detection of CAD in asymptomatic HD patients. The correlation between CAC score and aortic PWV raises the possibility that CAC score represents more an indicator of coronary artery medial wall calcification than a marker of CAD.  相似文献   
169.
BACKGROUND: Osteopontin (OPN) is reported to have two distinct functions in kidney disease: Promotion of inflammation at sites of tissue injury, and inhibition of calcium oxalate monohydrate stone formation. However, many of the studies supporting these functions were carried out in animal models of acute renal injury or in cultured cells; thus, the role of OPN in chronic renal disease is not well defined. We examined the role of OPN in adenine phosphoribosyltransferase (Aprt) knockout mice, in which inflammation and formation of 2,8-dihydroxyadenine (DHA) kidney stones are prominent features, by generating Aprt/Opn double knockout mice. METHODS: We characterized the phenotypes of six- and 12-week-old Aprt-/- Opn-/-, Aprt-/- Opn+/+, Aprt+/+ Opn-/-, and Aprt+/+ Opn+/+ male and female mice using biochemical, histologic, immunohistochemical, and in situ hybridization techniques. RESULTS: At 6 weeks of age, there was no difference in phenotype between double knockout and Aprt knockout mice. At 12 weeks, there was increased adenine and DHA excretion, renal crystal deposition, and inflammation in double knockout versus Aprt knockout male mice. Double knockout and Aprt knockout female mice at 12 weeks had less pathology than their male counterparts, but kidneys from double knockout females showed more inflammation compared with Aprt knockout females; both genotypes had similar levels of DHA crystal deposition. CONCLUSION: We conclude that (1) OPN is a major inhibitor of DHA crystal deposition and inflammation in male mice; and (2) OPN is a major modifier of the inflammatory response but not of crystal deposition in female mice. Thus, separate mechanisms appear responsible for the tissue changes seen in DKO males versus females.  相似文献   
170.
Ectopic thyroid tissue in the lower neck with a coexisting normally located multinodular goiter is a rare entity. We present a 27-year old asymptomatic woman with a recent history of a painless mass in the left side of her lower neck. Thyroid function tests were normal. An ultrasound of her neck showed a multinodular goiter and a 3.4 cm solid mass in the left lower cervical area. These findings were confirmed by an MRI scan of her neck. The Tc99m Pertechnetate scan showed the presence of a functioning area under the left lobe of the thyroid gland. The patient underwent surgery. The cervical mass was identified as a structure separate from the left lobe of the thyroid, without any attachments to the body of the gland and was uniformly resected. A subtotal thyroidectomy was also performed. The histology revealed that the separate structure represented ectopic thyroid tissue. The patient had an uneventful postoperative recovery, subsequent to which she was euthyroid and had normal calcium levels.  相似文献   
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