We studied HSA measurements in relation to hip fracture risk in 4806 individuals (2740 women). Hip fractures (n = 147) occurred at the same absolute levels of bone instability in both sexes. Cortical ...instability (propensity of thinner cortices in wide diameters to buckle) explains why hip fracture risk at different BMD levels is the same across sexes.
Introduction: Despite the sexual dimorphism of bone, hip fracture risk is very similar in men and women at the same absolute BMD. We aimed to elucidate the main structural properties of bone that underlie the measured BMD and that ultimately determines the risk of hip fracture in elderly men and women.
Materials and Methods: This study is part of the Rotterdam Study (a large prospective population‐based cohort) and included 147 incident hip fracture cases in 4806 participants with DXA‐derived hip structural analysis (mean follow‐up, 8.6 yr). Indices compared in relation to fracture included neck width, cortical thickness, section modulus (an index of bending strength), and buckling ratio (an index of cortical bone instability). We used a mathematical model to calculate the hip fracture distribution by femoral neck BMD, BMC, bone area, and hip structure analysis (HSA) parameters (cortical thickness, section modulus narrow neck width, and buckling ratio) and compared it with prospective data from the Rotterdam Study.
Results: In the prospective data, hip fracture cases in both sexes had lower BMD, thinner cortices, greater bone width, lower strength, and higher instability at baseline. In fractured individuals, men had an average BMD that was 0.09 g/cm2 higher than women (p < 0.00001), whereas no significant difference in buckling ratios was seen. Modeled fracture distribution by BMD and buckling ratio levels were in concordance to the prospective data and showed that hip fractures seem to occur at the same absolute levels of bone instability (buckling ratio) in both men and women. No significant differences were observed between the areas under the ROC curves of BMD (0.8146 in women and 0.8048 in men) and the buckling ratio (0.8161 in women and 0.7759 in men).
Conclusions: The buckling ratio (an index of bone instability) portrays in both sexes the critical balance between cortical thickness and bone width. Our findings suggest that extreme thinning of cortices in expanded bones plays a key role on local susceptibility to fracture. Even though the buckling ratio does not offer additional predictive value, these findings improve our understanding of why low BMD is a good predictor of fragility fractures.
Background: Axillary lymph node metastasis (ALNM) represents the single most important prognostic indicator in patients diagnosed with breast cancer. The proportion of ≤ 1-cm (T1a, T1b) invasive ...breast carcinomas is increasing. The incidence and predictive factors associated with ALNM in patients with ≤ 1-cm tumors remains unclear and the role of axillary lymph node dissection in these patients has been questioned. The purpose of this study was to determine clinical and pathologic factors predictive of ALNM in patients with ≤ 1-cm invasive breast carcinomas by univariate and multivariate analyses.
Study Design: Review analysis from a prospective database identified patients with ≤ 1-cm invasive breast cancers treated at our institution between 1990 and 1996. All patients underwent a resection of the primary tumor and axillary lymph node dissections. Routine patient and tumor characteristics evaluated included: age, race, tumor size, histologic grade, estrogen and progesterone receptor status, and lymphatic and vascular invasion. Univariate and multivariate analyses were performed. Adjusted odds ratios (OR) and 95% confidence intervals (CI) are presented.
Results: A total of 919 patients were identified in this study with tumors ≤ 1 cm. These included 199 patients (21.7%) with T1a tumors and 720 patients (78.3%) with T1b tumors. ALNM was detected in 165 patients with an overall incidence of 18.0%. Of the ALNM group, 32 patients (19.4%) had T1a tumors and 133 patients (80.6%) had T1b tumors. Four variables were found to be significant in univariate analysis. These included: increasing tumor size, poor histologic grade, presence of lymphatic or vascular invasion, and younger age of the patient. An increase in tumor size was associated with a significant risk of ALNM (OR = 2.66, 95% CI = 1.28 to 5.75; p = 0.01). Poor tumor grade and the presence of lymphatic or vascular invasion were also associated with an increased risk of ALNM (OR = 2.69, p = 0.003 and OR = 5.52, p = 0.0001, respectively). Patients with ALNM were more likely to have a tumor grade of 3 (25.0% ALNM versus 12.5% node-negative, p = 0.004) and lymphatic or vascular invasion (16.9% ALNM versus 3.5% node-negative, p < 0.0001). In multivariate analysis, an increased risk of ALNM was demonstrated with increasing tumor size (0.1-cm increments), poor histologic grade, and younger age.
Conclusions: This study investigated clinical and pathologic factors influencing ALNM in patients with T1a and T1b breast carcinomas. We have identified three factors by multivariate analysis as significant independent predictors of ALNM in this group of patients. These include increasing tumor size, poor histologic grade, and younger age. Given the significant amount of ALNM demonstrated in this study (overall 18%) and the inability to identify a subgroup of patients that had an acceptable low risk of ALNM, the complete omission of assessing the axilla for metastatic disease in patients with small breast cancers cannot be advocated. Our recommendation for patients diagnosed with T1a and T1b tumors is to have their axilla investigated for metastatic disease either by traditional axillary lymph node dissections or by intraoperative lymphatic mapping and sentinel lymph node biopsy techniques.
Mitochondrial DNA copy number (mtDNA-CN) measured from blood specimens is a minimally invasive marker of mitochondrial function that exhibits both inter-individual and intercellular variation. To ...identify genes involved in regulating mitochondrial function, we performed a genome-wide association study (GWAS) in 465,809 White individuals from the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium and the UK Biobank (UKB). We identified 133 SNPs with statistically significant, independent effects associated with mtDNA-CN across 100 loci. A combination of fine-mapping, variant annotation, and co-localization analyses was used to prioritize genes within each of the 133 independent sites. Putative causal genes were enriched for known mitochondrial DNA depletion syndromes (
p
= 3.09 × 10
–15
) and the gene ontology (GO) terms for mtDNA metabolism (
p
= 1.43 × 10
–8
) and mtDNA replication (
p
= 1.2 × 10
–7
). A clustering approach leveraged pleiotropy between mtDNA-CN associated SNPs and 41 mtDNA-CN associated phenotypes to identify functional domains, revealing three distinct groups, including platelet activation, megakaryocyte proliferation, and mtDNA metabolism. Finally, using mitochondrial SNPs, we establish causal relationships between mitochondrial function and a variety of blood cell-related traits, kidney function, liver function and overall (
p
= 0.044) and non-cancer mortality (
p
= 6.56 × 10
–4
).
Macrophage expression of cyclooxygenase-2 (COX-2), the inducible isoform of COX, is up-regulated by pro-inflammatory stimuli both in vivo and in vitro. Here we investigated the mechanisms ...regulatingCOX-2 gene expression in macrophage/monocytic cells. Lipopolysaccharide (LPS) is known to induce de novo COX-2 mRNA expression in these cells. Transient cotransfections with aCOX-2 promoter-luciferase construct and different expression vectors showed that LPS up-regulatesCOX-2 transcription through both mitogen-activated protein kinase (MAPK) and protein kinase C (PKC) pathways. Cotransfections with expression vectors for dominant negative mutants of MAPK and PKC isoforms did not suppress the effects of LPS on COX-2. Electrophoretic mobility shift assays and transient transfection experiments with deleted and mutated variants of a COX-2 promoter-luciferase construct showed that NFκB, NF-IL6, and CRE promoter sites mediate gene transcription independently in response to LPS treatment. In these experiments, isolated NFκB, NF-IL6, and CRE promoter sites were less effective than the intact promoter in mediating COX-2 transcription. Cotransfections with mutated COX-2 promoter-luciferase constructs and expression vectors showed that each one of these promoter elements can be activated by LPS through both MAPK and PKC pathways to induce gene expression. In summary, there is redundancy in the signaling pathways and promoter elements regulatingCOX-2 transcription in endotoxin-treated cells of macrophage/monocytic lineage.
Nutritional support of the cancer patient Rivadeneira, D. E; Evoy, D; Fahey, T. J., 3rd ...
CA: a cancer journal for clinicians,
March/April 1998, Letnik:
48, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Malnutrition, a common problem in cancer patients, adversely affects survival and quality of life. It results from several factors that alter nutritional intake and cause massive metabolic ...disturbances. Anticancer therapies may compound the malnutrition. Optimal nutrition improves therapeutic modalities and the clinical course and outcome. Oral nutrition should be used whenever possible; in patients unable to ingest adequate amounts orally, enteral and parenteral feedings are safe and effective.
In view of the population-specific heterogeneity in reported genetic risk factors for Parkinson's disease (PD), we conducted a genome-wide association study (GWAS) in a large sample of PD cases and ...controls from the Netherlands. After quality control (QC), a total of 514,799 SNPs genotyped in 772 PD cases and 2024 controls were included in our analyses. Direct replication of SNPs within SNCA and BST1 confirmed these two genes to be associated with PD in the Netherlands (SNCA, rs2736990: P = 1.63 × 10(-5), OR = 1.325 and BST1, rs12502586: P = 1.63 × 10(-3), OR = 1.337). Within SNCA, two independent signals in two different linkage disequilibrium (LD) blocks in the 3' and 5' ends of the gene were detected. Besides, post-hoc analysis confirmed GAK/DGKQ, HLA and MAPT as PD risk loci among the Dutch (GAK/DGKQ, rs2242235: P = 1.22 × 10(-4), OR = 1.51; HLA, rs4248166: P = 4.39 × 10(-5), OR = 1.36; and MAPT, rs3785880: P = 1.9 × 10(-3), OR = 1.19).
Several genome-wide association studies have been performed on warfarin. For acencoumarol, the most frequently used coumarin in many countries worldwide, pharmcodynamic influences are expected to be ...comparable. Pharmacokinetics however might differ. We aimed to confirm known or identify new genetic variants contributing to interindividual variation on stabilized acenocoumarol dosage by a GWAS. The index population consisted of 1451 Caucasian subjects from the Rotterdam study and results were replicated in 287 subjects from the Rotterdam study extended cohort. Both cohorts were genotyped on the Illumina 550K Human Map SNP array. From polymorphisms tested for association with acenocoumarol dosage, 35 single nucleotide polymorphisms (SNPs) on chromosome 16 and 18 SNPs on chromosome 10 reached genome-wide significance. The SNP with the lowest P-value was rs10871454 on chromosome 16 linked to SNPs within the vitamin K epoxide reductase complex subunit 1 (VKORC1) (P = 2.0 × 10−123). The lowest P-value on chromosome 10 was obtained by rs4086116 within cytochrome P450 2C9 (CYP2C9) (P = 3.3 × 10−24). After adjustment for these SNPs, the rs2108622 polymorphism within cytochrome P450 4F2 (CYP4F2) gene on chromosome 19 reached genome-wide significance (P = 2.0 × 10−8). On chromosome 10, we further identified genetic variation in the cytochrome P450 2C18 (CYP2C18) gene contributing to variance of acenocoumarol dosage. Thus we confirmed earlier findings that acenocoumarol dosage mainly depends on polymorphisms in the VKORC1 and CYP2C9 genes. Besides age, gender, body mass index and target INR, one polymorphism within each of the VKORC1, CYP2C9, CYP4F2 and CYP2C18 genes could explain 48.8% of acencoumarol dosage variation.
Background: Pancreatic anastomotic failure has historically been regarded as one of the most feared complications after pancreaticoduodenectomy.
Methods: We reviewed our recent experience (59 cases), ...March 1994 to December 1998, with pancreaticoduodenectomy and compared preoperative and intraoperative characteristics as well as outcomes in those patients who experienced (n = 10) versus those who did not experience a postoperative pancreatic leak (n = 49). Information was retrospectively collected from hospital records, office records, and interviews with patients.
Results: The clinical leak rate in this series was 8.5%. There were no significant differences in preoperative or intraoperative characteristics comparing those with versus those without a postoperative pancreatic leak. Only 1 of 10 patients with a postoperative pancreatic leak required reoperation to manage the leak. Those with a pancreatic leak had more other postoperative complications (median 2 versus 0 complications per patient,
P = 0.01) and longer hospital duration compared with those without a leak (median 13 versus 23 days,
P <0.01). Overall mortality in the series was 3.4%; no mortalities occurred as a result of a pancreatic leak.
Conclusions: In the 1990s pancreatic anastomotic leak remains a potentially lethal problem after pancreaticoduodenectomy. Pancreatic leakage after pancreaticoduodenectomy is associated with other postoperative complications and a longer hospital stay.
CD8
T cells are critical for elimination of cancer cells. Factors within the tumor microenvironment (TME) can drive these cells to a hypofunctional state known as exhaustion. The most terminally ...exhausted T (tT
) cells are resistant to checkpoint blockade immunotherapy and might instead limit immunotherapeutic efficacy. Here we show that intratumoral CD8
tT
cells possess transcriptional features of CD4
Foxp3
regulatory T cells and are similarly capable of directly suppressing T cell proliferation ex vivo. tT
cell suppression requires CD39, which generates immunosuppressive adenosine. Restricted deletion of CD39 in endogenous CD8
T cells resulted in slowed tumor progression, improved immunotherapy responsiveness and enhanced infiltration of transferred tumor-specific T cells. CD39 is induced on tT
cells by tumor hypoxia, thus mitigation of hypoxia limits tT
suppression. Together, these data suggest tT
cells are an important regulatory population in cancer and strategies to limit their generation, reprogram their immunosuppressive state or remove them from the TME might potentiate immunotherapy.
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