Pseudomonas pseudoalcaligenes KF707 grown with biphenyl expresses a cytochrome caa(3) oxidase that uses cytochrome c(4) as electron donor

Combining peroxidase activity-based heme staining (TMBZ/SDS/PAGE) with mass spectrometry analyses (Nano LC-MS/MS) of protein extracts from wild-type and appropriate mutants, we provide evidence that the polychlorinated biphenyl degrader Pseudomonas pseudoalcaligenes KF707 primarily expresses a caa3-type cytochrome c oxidase (caa3-Cox) using cytochrome (cyt) c4as an electron donor in cells grown with biphenyl versus glucose as the sole carbon source. Homology modeling of KF707 caa3-Cox using the three-dimensional structure of that from Thermus thermophilus highlights multiple similarities and differences between the proton channels in subunit I of the aa3- and caa3-Cox of Paracoccus and Thermus spp., respectively. To our knowledge, this is the first report demonstrating the presence of a caa3-Cox using cyt c4as an electron donor in a Pseudomonas species

Intermonomer Electron Transfer between the <i>b</i> Hemes of Heterodimeric Cytochrome <i>bc</i>₁

The ubihydroquinone:cytochrome <i>c</i> oxidoreductase, or cytochrome <i>bc</i>₁, is a central component of respiratory and photosynthetic energy transduction pathways in many organisms. It contributes to the generation of membrane potential and proton gradient used for cellular energy (ATP) production. The three-dimensional structures of cytochrome <i>bc</i>₁ show a homodimeric organization of its three catalytic subunits. The unusual architecture revived the issue of whether the monomers operate independently or function cooperatively during the catalytic cycle of the enzyme. In recent years, different genetic approaches allowed the successful production of heterodimeric cytochrome <i>bc</i>₁ variants and evidenced the occurrence of intermonomer electron transfer between the monomers of this enzyme. Here we used a version of the “two-plasmid” genetic system, also described in the preceding paper (DOI: 10.1021/bi400560p), to study a new heterodimeric mutant variant of cytochrome <i>bc</i>₁. The strain producing this heterodimeric variant sustained photosynthetic growth of <i>Rhodobacter capsulatus</i> and yielded an active heterodimer. Interestingly, kinetic data showed equilibration of electrons among the four <i>b</i> heme cofactors of the heterodimer, via “reverse” intermonomer electron transfer between the <i>b</i>_L hemes. Both inactive homodimeric and active heterodimeric cytochrome <i>bc</i>₁ variants were purified to homogeneity from the same cells, and purified samples were subjected to mass spectrometry analyses. The data unequivocally supported the idea that the cytochrome <i>b</i> subunits carried the expected mutations and their associated epitope tags. Implications of these findings on our interpretation of light-activated transient cytochrome <i>b</i> and <i>c</i> redox kinetics and the mechanism of function of a dimeric cytochrome <i>bc</i>₁ are discussed with respect to the previously proposed heterodimeric Q cycle model

Clinical and histopathological factors associated with Ki-67 expression in breast cancer patients

WOS: 000350918100005The aim of the present study was to identify the optimal Ki-67 cut-off value in breast cancer (BC) patients, and investigate the association of Ki-67 expression levels with other prognostic factors. Firstly, a retrospective search was performed to identify patients with stage I-III BC (n=462). A range of Ki-67 index values were then assigned to five groups (= 25%). The correlation between the Ki-67 index and other prognostic factors [age, tumor type, histological and nuclear grade, tumor size, multifocality, an in situ component, lymphovascular invasion (LVI), estrogen and progesterone receptor (ER/PR) expression, human epidermal growth factor receptor (HER-2) status, axillary involvement and tumor stage] were investigated in each group. The median Ki-67 value was revealed to be 20% (range, 1-95%). A young age (= 15% was associated with the largest number of poor prognostic factors (P=0.036). In addition, a Ki-67 value of >= 15% was identified to be statistically significant in association with certain luminal subtypes. The rate of disease-free survival was higher in patients with luminal A subtype BC (P=0.036). Following the correlation analysis for the Ki-67 index and the other prognostic factors, a Ki-67 value of >= 15% was revealed to be the optimal cut-off level for BC patients

Bioelectrical Impedance for Detecting and Monitoring Lymphedema in Patients with Breast Cancer. Preliminary Results of the Florence Nightingale Breast Study Group

WOS: 000350883800006PubMed ID: 25526543The aim of this study was to evaluate the efficacy of bioimpedance spectroscopy for the follow-up of patients with lymphedema in Turkey and its benefits in the diagnosis of stage 0, 1, and 2 lymphedema in patients who are under treatment for breast cancer. Thirty-seven female patients with breast cancer who underwent surgical procedures in our Breast Health Centre were followed up for lymphedema using bioimpedance, and clinical measurements were taken for a minimum period of 1 year at 3-month intervals. Patients who had been monitored regularly between November, 2011, and September, 2013, were enrolled to the study. In total, 8 patients developed lymphedema with an overall rate of 21.6%. Among the 8 patients who developed lymphedema, 4 had Stage 2, 1 had Stage 1, and 3 had Stage 0 lymphedema. Stage 0 lymphedema could not be detected with clinical measurements. During the patients' 1-year follow-up period using measurements of bioimpedance, a statistically significant relationship was observed between the occurrence of lymphedema and the disease characteristics. including the number of the extracted and remaining lymph nodes and the region of radiotherapy (p=0.042, p=0.024, p=0.040). Bioimpedance analysis seems to be a practical and reliable method for the early diagnosis of lymphedema. It is believed that regular monitoring of patients in the high-risk group using bioimpedance analyses increases the ability to treat lymphedema

Stereotactic Vacuum-Assisted Core Biopsy Results for Non-Palpable Breast Lesions

WOS: 000343722900012PubMed ID: 25040970Background: The increase in breast cancer awareness and widespread use of mammographic screening has led to an increased detection of (non-palpable) breast cancers that cannot be discovered through physical examination. One of the methods used in the diagnosis of these cancers is vacuum-assisted core biopsy, which prevents a considerable number of patients from undergoing surgical procedures. The aim of this study was to present the results of stereotactic vacuum-assisted core biopsy for suspicious breast lesions. Materials and Methods: Files were retrospectively scanned and data on demographic, radiological and pathological findings were recorded for patients who underwent stereotactic vacuum-assisted core biopsy due to suspicious mammographic findings at the Interventional Radiology Centre of the Florence Nightingale Hospital between January 2010, and April 2013. Statistical analysis was carried out using Pearson's Chi-square, continuity correction, and Fisher's exact tests. Results: The mean age of the patients was 47 years (range: 36-70). Biopsies were performed due to BIRADS 3 lesions in 8 patients, BIRADS 4 lesions in 77 patients, and BIRADS 5 lesions in 3 patients. Mammography elucidated clusters of microcalcifications in 73 patients (83%) and focal lesions (asymmetrical density, distortion) in 15 patients (17%). In terms of complications, 1 patient had a hematoma, and 2 patients had ecchymoses (3/88; 3.3%). The histopathologic results revealed benign lesions in 63 patients (71.6%) and malignant lesions in 25 patients (28.4%). The mean duration of the procedure was 37 minutes (range: 18-55). Although all of the BIRADS 3 lesions were benign, 22 (28.6%) of the BIRADS 4 lesions and all of the BIRADS 5 lesions were malignant. Among the malignant cases, 80% were in situ, and 20% were invasive carcinomas. These patients underwent surgery. Conclusions: In cases where non-palpable breast lesions are considered to be suspicious in mammography scans, the vacuum-assisted core biopsy method provides an accurate histopathologic diagnosis thus preventing a significant number of patients undergoing unnecessary surgical procedures

Clinical and histopathological factors associated with Ki-67 expression in breast cancer patients

The aim of the present study was to identify the optimal Ki-67 cut-off value in breast cancer (BC) patients, and investigate the association of Ki-67 expression levels with other prognostic factors. Firstly, a retrospective search was performed to identify patients with stage I-III BC (n=462). A range of Ki-67 index values were then assigned to five groups (= 25%). The correlation between the Ki-67 index and other prognostic factors [age, tumor type, histological and nuclear grade, tumor size, multifocality, an in situ component, lymphovascular invasion (LVI), estrogen and progesterone receptor (ER/PR) expression, human epidermal growth factor receptor (HER-2) status, axillary involvement and tumor stage] were investigated in each group. The median Ki-67 value was revealed to be 20% (range, 1-95%). A young age (= 15% was associated with the largest number of poor prognostic factors (P=0.036). In addition, a Ki-67 value of >= 15% was identified to be statistically significant in association with certain luminal subtypes. The rate of disease-free survival was higher in patients with luminal A subtype BC (P=0.036). Following the correlation analysis for the Ki-67 index and the other prognostic factors, a Ki-67 value of >= 15% was revealed to be the optimal cut-off level for BC patients

Bioelectrical Impedance for Detecting and Monitoring Lymphedema in Patients with Breast Cancer. Preliminary Results of the Florence Nightingale Breast Study Group

The aim of this study was to evaluate the efficacy of bioimpedance spectroscopy for the follow-up of patients with lymphedema in Turkey and its benefits in the diagnosis of stage 0, 1, and 2 lymphedema in patients who are under treatment for breast cancer. Thirty-seven female patients with breast cancer who underwent surgical procedures in our Breast Health Centre were followed up for lymphedema using bioimpedance, and clinical measurements were taken for a minimum period of 1 year at 3-month intervals. Patients who had been monitored regularly between November, 2011, and September, 2013, were enrolled to the study. In total, 8 patients developed lymphedema with an overall rate of 21.6%. Among the 8 patients who developed lymphedema, 4 had Stage 2, 1 had Stage 1, and 3 had Stage 0 lymphedema. Stage 0 lymphedema could not be detected with clinical measurements. During the patients' 1-year follow-up period using measurements of bioimpedance, a statistically significant relationship was observed between the occurrence of lymphedema and the disease characteristics. including the number of the extracted and remaining lymph nodes and the region of radiotherapy (p=0.042, p=0.024, p=0.040). Bioimpedance analysis seems to be a practical and reliable method for the early diagnosis of lymphedema. It is believed that regular monitoring of patients in the high-risk group using bioimpedance analyses increases the ability to treat lymphedema

Receptor discordance rate and its effects on survival in primary and recurrent breast cancer patients

Purpose: The receptor status of breast cancer plays a critical role in clinical practice. During the metastatic process, a change in the biological characteristics of the tumor can be seen. This study aimed to investigate the hormone receptor and HER2 status changes between primary and recurrent breast cancers and their effect on survival

A Global View of RNA-Protein Interactions Identifies Post-transcriptional Regulators of Root Hair Cell Fate

Foley SW, Gosai SJ, Wang D, et al. A Global View of RNA-Protein Interactions Identifies Post-transcriptional Regulators of Root Hair Cell Fate. Developmental Cell. 2017;41(2):204-220.e5.The Arabidopsis thaliana root epidermis is comprised of two cell types, hair and nonhair cells, which differentiate from the same precursor. Although the transcriptional programs regulating these events are well studied, post-transcriptional factors functioning in this cell fate decision are mostly unknown. Here, we globally identify RNA-protein interactions and RNA secondary structure in hair and nonhair cell nuclei. This analysis reveals distinct structural and protein binding patterns across both transcriptomes, allowing identification of differential RNA binding protein (RBP) recognition sites. Using these sequences, we identify two RBPs that regulate hair cell development.Specifically, we find that SERRATE functions in a microRNA-dependent manner to inhibit hair cellfate, while also terminating growth of root hairs mostly independent of microRNA biogenesis. In addition, we show that GLYCINE-RICH PROTEIN 8 promotes hair cell fate while alleviating phosphate starvation stress. In total, this global analysis revealspost-transcriptional regulators of plant root epidermal cell fate. Copyright 2017 Elsevier Inc. All rights reserved