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Comparison of fractal and grid electrodes for studying the effects of spatial confinement on dissociated retinal neuronal and glial behavior

Understanding the impact of the geometry and material composition of electrodes on the survival and behavior of retinal cells is of importance for both fundamental cell studies and neuromodulation applications. We investigate how dissociated retinal cells from C57BL/6J mice interact with electrodes made of vertically-aligned carbon nanotubes grown on silicon dioxide substrates. We compare electrod

A panel of kallikrein markers can predict outcome of prostate biopsy following clinical work-up : An independent validation study from the European Randomized Study of Prostate Cancer screening, France

Background: We have previously shown that a panel of kallikrein markers - total prostate-specific antigen (PSA), free PSA, intact PSA and human kallikrein-related peptidase 2 (hK2) - can predict the outcome of prostate biopsy in men with elevated PSA. Here we investigate the properties of our panel in men subject to clinical work-up before biopsy.Methods: We applied a previously published predicti

The relationship between prostate-specific antigen and prostate cancer risk : The prostate biopsy collaborative group

Purpose: The relationship between prostate-specific antigen (PSA) level and prostate cancer risk remains subject to fundamental disagreements. We hypothesized that the risk of prostate cancer on biopsy for a given PSA level is affected by identifiable characteristics of the cohort under study. Experimental Design: We used data from five European and three U.S. cohorts of men undergoing biopsy for

Finasteride to prevent prostate cancer : Should all men or only a high-risk subgroup be treated?

Purpose: Finasteride has been shown to reduce the incidence of prostate cancer. Yet the use of finasteride remains low, likely because of the risk of adverse effects. We sought to determine whether prostate-specific antigen (PSA) levels could identify a high-risk subgroup for which the benefits of finasteride treatment outweigh the potential harms. Patients and Methods: Raw data from the Prostate

Pan-cancer analysis of pre-diagnostic blood metabolite concentrations in the European Prospective Investigation into Cancer and Nutrition

Background: Epidemiological studies of associations between metabolites and cancer risk have typically focused on specific cancer types separately. Here, we designed a multivariate pan-cancer analysis to identify metabolites potentially associated with multiple cancer types, while also allowing the investigation of cancer type-specific associations. Methods: We analysed targeted metabolomics data

Changes in the upper airway volume after orthognathic surgery: three-dimensional measurements in a supine body position

The objectives of this study were to analyse the changes in airway cross-sectional areas and volumes due to surgical movements of the jaws and to identify any possible correlation with the direction of the movements. Fifty-seven participants, aged 18–28 years (mean 20.8 years) at surgery, were followed up for 12 months postoperatively. Pre- and postoperative measurements of the facial region obtai

Frequent carbon input primes decomposition of decadal soil organic matter

Soil organic matter (SOM) decomposition in response to global change represents a critical uncertainty in coupled carbon (C) cycle-climate models. Much of this uncertainty arises from our limited mechanistic knowledge of the effects of organic C input frequency on SOM decomposition. Based on a three-source-partitioning isotopic approach (14C glucose addition to soil continuously labeled by C4 plan

Immunoreactivity of recombinant human glandular kallikrein using monoclonal antibodies raised against prostate-specific antigen

The gene encoding human glandular kallikrein (KLK2) was expressed in Escherichia coli, and the corresponding protein (hK2) was produced by fermentation. The hK2 was characterized by Western blotting and epitope map using monoclonal antibodies (MAbs) specific for another protease, prostate- specific antigen (PSA) with high structural identity (80%). MAbs that recognized three different epitopes wer

Cloning and characterization of the α1-antichymotrypsin produced by human prostate tissue

BACKGROUND. α1-antichymotrypsin (ACT) forms stable complexes with prostate-specific antigen (PSA), a serine protease, and this complex is the major form of PSA in the blood circulation. α1-antichymotrypsin occurs in the blood in approximately 105 molar excess to PSA, mainly due to hepatic production, but local prostatic production of ACT has been demonstrated by immunohistochemistry and in situ hy

Enzymatic activation of a doxorubicin-peptide prodrug by prostate- specific antigen

New approaches to target cytotoxic therapy specifically to metastatic prostate cancer sites are urgently needed. As such an approach, an inactive prodrug was synthesized by coupling the primary amine of doxorubicin to the COOH-terminal carboxyl of a seven-amino acid peptide carrier (i.e., Mu-His- Ser-Ser-Lys-Leu-Gln-Leu). The seven-amino acid peptide was documented to be hydrolyzable specifically

Biomarkers of cellular aging during a controlled human malaria infection

Cellular aging is difficult to study in individuals with natural infection, given the diversity of symptom duration and clinical presentation, and the high interference of aging-related processes with host and environmental factors. To address this challenge, we took advantage of the controlled human malaria infection (CHMI) model. This approach allowed us to characterize the relationship among ce

Silk scaffolding drives self-assembly of functional and mature human brain organoids

Human pluripotent stem cells (hPSCs) are intrinsically able to self-organize into cerebral organoids that mimic features of developing human brain tissue. These three-dimensional structures provide a unique opportunity to generate cytoarchitecture and cell-cell interactions reminiscent of human brain complexity in a dish. However, current in vitro brain organoid methodologies often result in intra

Specific and efficient peptide substrates for assaying the proteolytic activity of prostate-specific antigen

Prostate-specific antigen (PSA) is a serine protease secreted by hath normal prostate glandular celts and prostate cancer cells. The major proteolytic substrates for PSA are the gel-forming proteins in semen, semenogelin (Sg) I and II. On the basis of the PSA cleavage map for Sg I and II, a series of small peptides (ie., ≤ 7 amino acids) was synthesized and coupled at the COOH terminus to 7-amino-

Characteristics of screening detected prostate cancer in men 50 to 66 years old with 3 to 4 ng./Ml. Prostate specific antigen

Purpose: We defined the yield and nature of prostate cancer in the setting of population based, randomized prostate specific antigen (PSA) guided screening in men with PSA levels between 3 and 4 ng./ml. who were 50 to 65 years old at the time of randomization. Materials and Methods: Sextant biopsies were performed in 243 men with PSA of 3 to 4 ng./ml. Therapy decisions were based on core cancer le

Immunohistochemical and in situ hybridization studies of β- microseminoprotein in the human gastric mucosa

β-Microseminoprotein is a 10-kDa disulphide-rich protein with unknown function which is present in the mucus of the airways, gastrointestinal tract and urogenital tract. In this paper, an investigation of the distribution of β-microseminoprotein in the human stomach is reported. Immunohistochemistry and in situ hybridization were used. β-Microseminoprotein was found to be localized mainly in the a

In vitro stability of free prostate-specific antigen (PSA) and prostate- specific antigen (PSA) complexed to α1-antichymotrypsin in blood samples

Objectives. To study the in vitro stability of free and complexed forms of prostate specific antigen (PSA) in blood samples in order to establish guidelines for specimen handling, in particular for the clinical utility of the analysis of percentage free PSA. Methods. Blood samples were collected and processed to generate serum, heparin plasma, and EDTA plasma. Three different two-site immunoassays

A comparison of the free fraction of serum prostate specific antigen in men with benign and cancerous prostates : The best case scenario

Purpose: In most previous studies of free-to-total serum prostate specific antigen (PSA) ratios, the specimens from patients with prostate cancer or those with benign prostatic hyperplasia (BPH) have not been highly characterized. We compared preoperative sera from post-radical prostatectomy patients with clinically significant cancers of at least 2 cm.3 to sera from those with BPH and large, biop

Structural investigation of the alpha-1-antichymotrypsin : Prostate-specific antigen complex by comparative model building

Prostate-specific antigen (PSA), produced by prostate cells, provides an excellent serum marker for prostate cancer. It belongs to the human kallikrein family of enzymes, a second prostate-derived member of which is human glandular kallikrein-1 (hK2). Active PSA and hK2 are both 237-residue kallikrein-like proteases, based on sequence homology. An hK2 model structure based on the serine protease f

Isolation and characterization of the major gel proteins in human semen, semenogelin I and semenogelin II

Semenogelin I and semenogelin II constitute the major gel-forming proteins in human semen. The gel proteins were rapidly solubilized and separated from spermatozoa in ejaculates collected at pH 9.7 in buffer containing 4 mol/l urea and dithiothreitol. This protected the semenogelins from proteolytic degradation by prostate-specific antigen, and allowed their isolation by affinity chromatograph:g o

Alteration of the hormonal bioactivity of parathyroid hormone-related protein (PTHrP) as a result of limited proteolysis by prostate-specific antigen

Objectives. To discover whether the proteolytic activity of prostate- specific antigen (PSA) affects the structure and function of parathyroid hormone-related protein (PTHrP), as both are abundant components of human seminal plasma. Methods. The ability of PTHrP to act as a substrate was studied by incubating a synthetic polypeptide, consisting of 34 amino acid residues of the amino-terminal domai