Semiquantitative Method (semiquantitative + method)

Distribution by Scientific Domains


Selected Abstracts


Expression of a novel marker, Ubc9, in squamous cell carcinoma of the head and neck,

HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 7 2009
Ohad Ronen MD
Abstract Background. Ubiquitin-conjugating enzyme (Ubc9) is a novel enzyme involved in posttranslational modification of cellular proteins. The objective of this study was to determine the expression of Ubc9 in squamous cell carcinoma of the head and neck (SCCHN). Methods. SCCHN specimens were stained with anti-Ubc9 antibodies, scored using a semiquantitative method, and statistically analyzed. Results. Forty-six tumors were stained, 26 of which included adjacent mucosa. Ubc9 was significantly upregulated in the malignant and peritumoral tissues compared with mucosa from normal individuals. In peritumoral tissues, Ubc9 expression was detected in the basal and suprabasal epithelial layers. No Ubc9 was detected in epithelial cells in normal mucosa. These differences in Ubc9 expression were statistically significant (p < .0001). Tumor Ubc9 expression significantly correlated with clinical and pathologic stage. Conclusions. Ubc9 is significantly overexpressed in the primary SCCHN tumors and peritumoral mucosa compared with normal epithelial cells. These findings suggest that Ubc9 may play an important role in tumorigenesis and tumor progression of SCCHN. © 2009 Wiley Periodicals, Inc. Head Neck, 2009 [source]


Calcifications in the Abdominal Aorta Predict Fractures in Men: MINOS Study,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 1 2008
Pawel Szulc MD
In a cohort of 781 men ,50 yr of age followed up for 10 yr, extended calcifications in the abdominal aorta were associated with a 2- to 3-fold increase in the risk of osteoporotic fractures regardless of BMD and falls. Introduction: Cardiovascular disease and osteoporotic fractures are public health problems that frequently coexist. Materials and Methods: We assessed the relation of the severity of aortic calcifications with BMD and the risk of fracture in 781 men ,50 yr of age. During a 10-year follow-up, 66 men sustained incident clinical fractures. Calcifications in the abdominal aorta expressed as an aortic calcification score (ACS) were assessed by a semiquantitative method. BMD was measured at the lumbar spine, hip, whole body, and distal forearm. Results: ACS > 2 was associated with a 2-fold increase in the mortality risk after adjustment for age, weight, smoking, comorbidity, and medications. After adjustment for age, body mass index (BMI), smoking, and comorbidity, men in the highest quartile of ACS (>6) had lower BMD of distal forearm, ultradistal radius, and whole body than men in the lower quartiles. Log-transformed ACS predicted fractures when adjusted for age, BMI, age by BMI interaction, prevalent fractures, BMD, and history of two or more falls (e.g., hip BMD; OR = 1.44; p < 0.02). ACS, BMD at all the skeletal sites, and history of two or more falls were independent predictors of fracture. Men with ACS > 6 had a 2- to 3-fold increased risk of fracture after adjustment for confounding variables (OR = 2.54-3.04; p < 0.005-0.001 according to the site). Conclusions: This long-term prospective study showed that elevated ACS (>6) is a robust and independent risk factor for incident fracture in older men regardless of age, BMI, BMD, prevalent fractures, history of two or more falls, comorbidities, and medications. [source]


Underdiagnosis of Vertebral Fractures Is a Worldwide Problem: The IMPACT Study

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2005
Pierre D Delmas MD
Abstract Accurate radiographic diagnosis of vertebral fractures is important. This multicenter, multinational study assessed radiographic diagnoses of vertebral fracture in 2451 postmenopausal women with osteoporosis. Comparison between local and central readings yielded a false-negative rate of 34%. Underdiagnosis of vertebral fracture is a worldwide problem. Introduction: Vertebral fractures are the most common complication of osteoporosis. Although they are associated with significant morbidity, they frequently do not come to clinical attention. Accurate radiographic diagnosis is important. Materials and Methods: In a multicenter, multinational prospective study (the IMPACT trial), the accuracy of radiographic diagnosis of vertebral fracture was evaluated in postmenopausal women 65,80 years of age newly diagnosed with osteoporosis (based on BMD measurement). Lateral radiographs of the thoracolumbar spine were evaluated for identification of vertebral fractures, first locally and subsequently at a central reading center, using a validated semiquantitative method. False-positive and false-negative rates were calculated based on adjudicated discrepancies between the initial interpretation at the local site and the subsequent central reading, considered the "reference standard." Results: Of 2451 women with an evaluable radiograph both centrally and locally, 789 (32%) had at least one vertebral fracture. Adjudicated discrepancies (n = 350 patients) between local and central readings because of undetected vertebral fracture (68%) or equivocal terminology in the local radiology report (32%) yielded a false-negative rate of 34%. Conclusions: Underdiagnosis of vertebral fractures was observed in all geographic regions (false-negative rates: North America, 45.2%; Latin America, 46.5%; Europe/South Africa/Australia, 29.5%). The false-positive rate was 5% globally. Underdiagnosis of vertebral fracture is a worldwide problem attributable in part to a lack of radiographic detection, use of ambiguous terminology in the radiology report, or both. Efforts to improve accuracy and reduce variability in terminology and interpretation may increase the effectiveness of spinal radiography for detecting vertebral fractures in patients with osteoporosis. [source]


Solid-state solubility influences encapsulation and release of hydrophobic drugs from PLGA/PLA nanoparticles

JOURNAL OF PHARMACEUTICAL SCIENCES, Issue 7 2004
Jayanth Panyam
Abstract Biodegradable nanoparticles formulated from poly(D,L -lactide- co -glycolide) (PLGA) and polylactide (PLA) polymers are being extensively investigated for various drug delivery applications. In this study, we hypothesize that the solid-state solubility of hydrophobic drugs in polymers could influence their encapsulation and release from nanoparticles. Dexamethasone and flutamide were used as model hydrophobic drugs. A simple, semiquantitative method based on drug,polymer phase separation was developed to determine the solid-state drug,polymer solubility. Nanoparticles using PLGA/PLA polymers were formulated using an emulsion,solvent evaporation technique, and were characterized for size, drug loading, and in vitro release. X-ray powder diffraction (XRD) and differential scanning calorimetry (DSC) were used to determine the physical state of the encapsulated drug. Results demonstrated that the solid-state drug,polymer solubility depends on the polymer composition, molecular weight, and end-functional groups (ester or carboxyl) in polymer chains. Higher solid-state drug,polymer solubility resulted in higher drug encapsulation in nanoparticles, but followed an inverse correlation with the percent cumulative drug released. The XRD and DSC analyses demonstrated that the drug encapsulated in nanoparticles was present in the form of a molecular dispersion (dissolved state) in the polymer, whereas in microparticles, the drug was present in both molecular dispersion and crystalline forms. In conclusion, the solid-state drug,polymer solubility affects the nanoparticle characteristics, and thus could be used as an important preformulation parameter. © 2004 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 93:1804,1814, 2004 [source]


A method for improving predictions of bed-load discharges to reservoirs

LAKES & RESERVOIRS: RESEARCH AND MANAGEMENT, Issue 2 2007
Vicente L. Lopes
Abstract Effective management options for mitigating the loss of reservoir water storage capacity to sedimentation depend on improved predictions of bed-load discharges into the reservoirs. Most predictions of bed-load discharges, however, are based on the assumption that the rates of bed-load sediment availability equal the transport capacity of the flow, ignoring the spatio-temporal variability of the sediment supply. This paper develops a semiquantitative method to characterize bed-load sediment transport in alluvial channels, assuming a channel reach is non-supply limited when the bed-load discharge of a given sediment particle-size class is functionally related to the energy that is available to transport that fraction of the total bed-load. The method was applied to 22 alluvial stream channels in the USA to determine whether a channel reach had a supply-limited or non-supply-limited bed-load transport regime. The non-supply-limited transport regime was further subdivided into two groups on the basis of statistical tests. The results indicated the pattern of bed-load sediment transport in alluvial channels depends on the complete spectrum of sediment particle sizes available for transport rather than individual particle-size fractions represented by one characteristic particle size. The application of the method developed in this paper should assist reservoir managers in selecting bed-load sediment transport equations to improve predictions of bed-load discharge in alluvial streams, thereby significantly increasing the efficiency of management options for maintaining the storage capacity of waterbodies. [source]


Study of p53 immunostaining in the gastric epithelium of cagA-positive and cagA-negative Helicobacter pylori gastritis

CANCER, Issue 3 2002
Ming Teh M.D.
Abstract BACKGROUND p53 mutations are an early event in the multistep progression of gastric carcinoma. These mutations are often present in dysplastic and intestinal metaplastic gastric epithelium. However, the presence of immunohistochemically detectable p53 protein and p53 mutations in nondysplastic/nonmetaplastic gastric mucosa is more controversial. Recent reports have suggested that immunohistochemically detectable p53 protein may be present in the gastric epithelium of Helicobacter pylori gastritis. Furthermore, because cagA-positive H. pylori is associated with greater mucosal injury but decreased apoptosis, it would be interesting to determine if this phenotype is associated with greater immunostaining of p53, as the wild-type p53 gene helps to initiate apoptosis. METHODS One hundred thirty-five patients with H. pylori -associated gastritis were immunohistochemically stained for p53 and quantified for the extent and intensity of the staining using a semiquantitative method (0, nil staining; 6, extensive and strong staining). The cagA status of the organism was determined by Western blot. RESULTS Thirty-one patients (23%) showed strong p53 staining (, 4 of 6) in inflamed but otherwise normal gastric epithelium. In the 123 cagA-positive H. pylori gastritis patients, the average p53 staining score was 2.5 of 6. This is significantly higher than the corresponding score of 1.7 of 6 observed in the 12 patients with cagA-negative H. pylori gastritis (P = 0.04). CONCLUSIONS Our results indicate that p53 protein is immunohistochemically detectable even before gastric metaplastic/dysplastic change occurs. The results also suggest that cagA-positive H. pylori might be associated with greater p53 immunohistochemical staining. This would indicate that p53 immunohistochemical staining does not reliably differentiate between gastric dysplasia and reactive inflammatory atypia. If the p53 protein detected is a consequence of mutation, this would help to explain why cagA-positive H. pylori gastritis is associated with decreased apoptosis. Cancer 2002;95:499,505. © 2002 American Cancer Society. DOI 10.1002/cncr.10697 [source]


Intravenous catheter infections associated with bacteraemia: a 2-year study in a University Hospital

CLINICAL MICROBIOLOGY AND INFECTION, Issue 5 2004
M. Paragioudaki
Abstract The aim of this retrospective study was to assess the incidence and aetiology of central and peripheral venous catheter (C/PVC) infections during a 2-year period (1999,2000) and to determine the susceptibility of isolated microorganisms to various antimicrobial agents. Catheter tips were processed using the semiquantitative method and blood cultures were performed with the BacT/Alert automated system. Antibiotic susceptibilities were performed by disk agar diffusion and MICs were determined by Etest, according to NCCLS standards. During the study period, samples from 1039 C/PVC infections were evaluated, yielding 384 (37.0%) positive cultures. Blood cultures were also available from 274 patients, of which 155 (56.6%) yielded the same microorganism as from the catheter. No bloodstream infections were detected in 104 C/PVC-positive cases. Methicillin-resistant coagulase-negative staphylococci were the most frequent isolates, followed by Gram-negative bacteria, especially Pseudomonas aeruginosa. Resistance to glycopeptides among staphylococci and enterococci was not detected, whereas 60% of Gram-negative bacilli were resistant to ,-lactams. [source]