scholarly journals Trichinella spiralis: specificity of ES antigens from pre-encysted larvae

1992 ◽  
Vol 66 (1) ◽  
pp. 38-44 ◽  
Author(s):  
R. C. Ko ◽  
T. P. Wong
Keyword(s):  
Molecular Mass ◽  
Sensitivity And Specificity ◽  
Trichinella Spiralis ◽  
Sds Page ◽  
Antibody Elisa ◽  
The Common ◽  
Low Sensitivity

ABSTRACTExcretory/secretory (ES) antigens were obtained by culturing pre-encysted Trichinella spiralis larvae which were recovered from muscles of experimentally infected mice 14–15 days postinfection. Analyses of these antigens (PEL ES) with immunoblotting, SDS-PAGE and Triple Antibody ELISA showed that they yielded a low sensitivity and specificity when tested antisera against the common nematodes of Chinese pigs. As compared to ES antigens from encysted larvae. PEL ES also contained more low molecular mass proteins.

scholarly journals Homodimer and heterodimer subunits of human prostate acid phosphatase

1991 ◽  
Vol 277 (3) ◽  
pp. 759-765 ◽  
Author(s):  
H Lee ◽  
T M Chu ◽  
S S L Li ◽  
C L Lee
Keyword(s):  
Acid Phosphatase ◽  
Molecular Mass ◽  
Prostatic Acid Phosphatase ◽  
Single Component ◽  
Molar Ratio ◽  
Antigenic Determinants ◽  
Human Seminal Plasma ◽  
Sds Page ◽  
The Common ◽  
Alpha Beta

Human prostatic acid phosphatase (PAP) isoenzymes, designated PAP-A and PAP-B, were isolated from human seminal plasma by sequential affinity chromatography on concanavalin A and L(+)-tartrate, a classic inhibitor of PAP. Both the major PAP-A and the minor PAP-B isoenzymes exhibited a similar molecular mass (100 and 105 kDa respectively), multiple pI values (5.05-5.35 and 5.05-5.12), and substrate and inhibitor specificity. Immunological characterization revealed that PAP-B possesses distinct antigenic determinants, in addition to the common sites shared with PAP-A. SDS/PAGE indicated that both isoenzymes are composed of two subunits of 50 kDa each. At high salt concentration, PAP-B dissociated completely into single subunits of 50 kDa, whereas PAP-A remained intact at 100 kDa. PAP-B was resolved by reverse-phase h.p.l.c. into three components, designated alpha, beta and gamma, each of 50 kDa, at a molar ratio of approx. 2:1:1. PAP-A contained a single component of molecular mass 50 kDa. The single component of PAP-A and the alpha component of PAP-B possessed identical amino acid compositions and N-terminal sequences, which were different from those of the beta and gamma components. These results indicate that human PAP contains three isoforms, alpha 2, alpha beta and alpha gamma. PAP-A, the major isoenzyme, is a homodimer consisting of two identical subunits (alpha 2), and PAP-B, the minor isoenzyme, is a mixture of two heterodimers, consisting of non-identical subunits (alpha beta and alpha gamma).

Detection of both Type 1 and Type 2 Plasminogen Activator Inhibitors in Human Monocytes

1990 ◽  
Vol 63 (01) ◽  
pp. 067-071 ◽  
Author(s):  
Joan C Castellote ◽  
Enric Grau ◽  
Maria A Linde ◽  
Nuria Pujol-Moix ◽  
Miquel LI Rutllant
Keyword(s):  
Molecular Mass ◽  
Plasminogen Activator ◽  
Human Peripheral Blood ◽  
Direct Interaction ◽  
Apparent Molecular Weight ◽  
Fibrinolytic System ◽  
Human Monocytes ◽  
Blood Monocytes ◽  
Single Chain ◽  
Sds Page

SummaryIncreasing evidence suggests the involvement of leukocytes in the fibrinolytic system. Monocytes secrete pro-urokinase (Grau, Thromb Res 1989; 53: 145) and it has been shown that these cells have specific receptors for urokinase and plasminogen (Miles, Thromb Haemostas 1987; 58: 936). The aim of this study was to analyse the presence of plasminogen activator inhibitor(s) in platelet-free suspensions of human peripheral blood monocytes and polymorphonuclear leukocytes (PMN). SDS-PAGE and reverse fibrin autography showed an inhibitory band of 50 kDa in the monocyte extracts (Triton X-100) but not in the PMN extracts. Urokinase (u-PA) was mixed with increasing amounts of monocyte extract for 10 min and the mixtures were added to 125Ifibrin coated wells containing plasminogen. A dose-dependent decrease in the u-PA fibrinolytic activity was observed. The amount of inhibition increased when the monocyte releasates were preincubated with u-PA (40% inhibition after 5 min preincubation and 80% after 15 min), indicating a direct interaction between this activator and an inhibitor(s). After SDS-PAGE of monocyte extracts, immunoblotting and peroxidase staining identified both PAI1 and PAI2, with an apparent molecular weight of 47-50 kDa. Monocyte-associated PAI1 formed complexes with single chain t-PA with a molecular mass 50 kDa higher than the molecular mass of the free PAI1. However, a significant amount of PAI remained unbound to t-PA. This inactive PAI1 could have come from a rapid inactivation of the primary active PAI1. These PAI1 and PAI2 detected in human monocytes may be transcendent in the regulation of the fibrinolytic system.

RESEARCH ON VALUE OF INTRAOPERATIVE FROZEN SECTION EXAMINATION OF THE COMMON TUMORS AT HUE UNIVERSITY HOSPITAL

2011 ◽  
pp. 67-73
Author(s):  
Cong Thuan Dang ◽  
Thi Thu Thao Le
Keyword(s):  
Sensitivity And Specificity ◽  
Frozen Section ◽  
Analysis Data ◽  
Poor Quality ◽  
University Hospital ◽  
Frozen Sections ◽  
Intraoperative Frozen Section ◽  
Frozen Section Examination ◽  
Incorrect Diagnosis ◽  
The Common

Background: To evaluate the accuracy and the pitfalls of frozen section examination in diagnosis the common tumors at Hue University Hospital. Materials and method: A retrospective analysis data of 99 consecutive patients from 2007 to 2009 were evaluated and analyzed the major pitfalls. In our 99 patients, 100% cases we compared histological diagnosis on frozen sections with those on paraffin sections. Results: The majority of frozen section examinations were the thyroid lesions 37.4%, breast lesions 25.2%, lymph nodes 16.1%, ovary 9.1% and less common in other diseases (12.1%). The accuracy, sensitivity and specificity of the intraoperative frozen section examination were 93.9%, 89.1% and 98.1% respectively. The main factors causing incorrect diagnosis in frozen section are: Misinterpretation, poor quality of frozen sections, improper sampling in sectioning and difficult to result interpretation. Conclusion: The frozen section analysis of suspect lesions displays good sensitivity and specificity characteristics.

Extracellular Vesicles in Tumor Diagnosis: A Mini-Review

2020 ◽  
Vol 20 ◽  
Author(s):  
Si Yu ◽  
Menglin Huang ◽  
Jingyu Wang ◽  
Yongchang Zheng ◽  
Haifeng Xu
Keyword(s):  
Clinical Diagnosis ◽  
Sensitivity And Specificity ◽  
Cancer Diagnosis ◽  
Cancer Biomarkers ◽  
Related Substances ◽  
Physiological Processes ◽  
Cancer Pathogenesis ◽  
Limited Application ◽  
Low Sensitivity ◽  
Shed Light

: Widely exploration of noninvasive tumor/cancer biomarkers has shed light on clinical diagnosis. However, many under-investigated biomarkers showed limited application potency due to low sensitivity and specificity, while extracellular vehicles (EVs) were gradually recognized as promising candidates. EVs are small vesicles transporting bioactive cargos between cells in multiple physiological processes and also in tumor/cancer pathogenesis. This review aimed to offer recent studies of EVs on structure, classification, physiological functions, as well as changes in tumor initiation and progression. Furthermore, we focused on advances of EVs and/or EV-related substances in cancer diagnosis, and summarized ongoing studies of promising candidates for future investigations.

scholarly journals Comparing the Diagnostic Value of Serum D-Dimer to CRP and IL-6 in the Diagnosis of Chronic Prosthetic Joint Infection

2020 ◽  
Vol 9 (9) ◽  
pp. 2917
Author(s):  
Thomas Ackmann ◽  
Burkhard Möllenbeck ◽  
Georg Gosheger ◽  
Jan Schwarze ◽  
Tom Schmidt-Braekling ◽  
...  
Keyword(s):  
Sensitivity And Specificity ◽  
Joint Infection ◽  
Revision Arthroplasty ◽  
Preoperative Assessment ◽  
Diagnostic Value ◽  
Musculoskeletal Infection ◽  
Prosthetic Joint ◽  
The Individual ◽  
Low Sensitivity ◽  
D Dimer

Introduction: D-dimer is a diagnostic criterion for periprosthetic joint infection (PJI) of the Musculoskeletal Infection Society (MSIS) in 2018. The aim of this study was to evaluate the serum D-dimer values in comparison to C-reactive protein (CRP) and interleukin-6 (IL-6) for the diagnosis of PJI. Materials and Methods: We included 119 patients (50 women, 69 men; 71 knees, 48 hips) undergoing revision arthroplasty with preoperative assessment of CRP, IL-6, and serum D-dimer. Cases were classified as infected or aseptic based on the MSIS criteria of 2018. Receiver operating curves and Youden’s index were used to define an ideal cut-off value and sensitivity and specificity for the individual parameters, and respective combinations were calculated using cross-tables. Results: The median D-dimer level (2320 vs. 1105 ng/mL; p < 0.001), the median CRP level (4.0 vs. 0.5 mg/dL; p < 0.001), and the median IL-6 level (21.0 vs. 5.0 pg/mL; p < 0.001) were significantly higher in the group of PJI compared to the group with aseptic failure. The calculated optimal cut-off values were 2750 ng/mL (AUC 0.767) for D-dimer, 1.2 mg/dL (AUC 0.914) for CRP, and 10.0 pg/mL (AUC 0.849) for IL-6. D-dimer showed a sensitivity of 38% and specificity of 94%, whereas the CRP and IL-6 had sensitivities of 88% and 76%, and specificities of 87% and 92%, respectively. Conclusion: In comparison with CRP and IL-6, serum D-dimer showed low sensitivity and specificity in our cohort. While CRP and IL-6 combination had the highest sensitivity, a combination of Il-6 and D-dimer or CRP and IL-6 had the highest specificity.

scholarly journals Evaluation of Recombinant Proteins of Burkholderia mallei for Serodiagnosis of Glanders

2012 ◽  
Vol 19 (8) ◽  
pp. 1193-1198 ◽  
Author(s):  
Vijai Pal ◽  
Subodh Kumar ◽  
Praveen Malik ◽  
Ganga Prasad Rai
Keyword(s):  
Sensitivity And Specificity ◽  
Recombinant Proteins ◽  
False Negative ◽  
Enzyme Linked Immunosorbent Assay ◽  
Burkholderia Mallei ◽  
Content Type ◽  
Whole Cells ◽  
Negative Results ◽  
Elisa Format ◽  
Low Sensitivity

ABSTRACTGlanders is a contagious disease caused by the Gram-negative bacillusBurkholderia mallei. The number of equine glanders outbreaks has increased steadily during the last decade. The disease must be reported to the Office International des Epizooties, Paris, France. Glanders serodiagnosis is hampered by the considerable number of false positives and negatives of the internationally prescribed tests. The major problem leading to the low sensitivity and specificity of the complement fixation test (CFT) and enzyme-linked immunosorbent assay (ELISA) has been linked to the test antigens currently used, i.e., crude preparations of whole cells. False-positive results obtained from other diagnostic tests utilizing crude antigens lead to financial losses to animal owners, and false-negative results can turn a risk into a possible threat. In this study, we report on the identification of diagnostic targets using bioinformatics tools for serodiagnosis of glanders. The identified gene sequences were cloned and expressed as recombinant proteins. The purified recombinant proteins ofB. malleiwere used in an indirect ELISA format for serodiagnosis of glanders. Two recombinant proteins, 0375H and 0375TH, exhibited 100% sensitivity and specificity for glanders diagnosis. The proteins also did not cross-react with sera from patients with the closely related disease melioidosis. The results of this investigation highlight the potential of recombinant 0375H and 0375TH proteins in specific and sensitive diagnosis of glanders.

scholarly journals Identification and characterization of Sulfolobus solfataricusD-gluconate dehydratase: a key enzyme in the non-phosphorylated Entner–Doudoroff pathway

2005 ◽  
Vol 387 (1) ◽  
pp. 271-280 ◽  
Author(s):  
Seonghun KIM ◽  
Sun Bok LEE
Keyword(s):  
Molecular Mass ◽  
Gel Filtration ◽  
Maximal Activity ◽  
Genome Database ◽  
Sds Page ◽  
Key Enzyme ◽  
Bivalent Metal Ions ◽  
Ammonium Sulphate Fractionation ◽  
Identification And Characterization

The extremely thermoacidophilic archaeon Sulfolobus solfataricus utilizes D-glucose as a sole carbon and energy source through the non-phosphorylated Entner–Doudoroff pathway. It has been suggested that this micro-organism metabolizes D-gluconate, the oxidized form of D-glucose, to pyruvate and D-glyceraldehyde by using two unique enzymes, D-gluconate dehydratase and 2-keto-3-deoxy-D-gluconate aldolase. In the present study, we report the purification and characterization of D-gluconate dehydratase from S. solfataricus, which catalyses the conversion of D-gluconate into 2-keto-3-deoxy-D-gluconate. D-Gluconate dehydratase was purified 400-fold from extracts of S. solfataricus by ammonium sulphate fractionation and chromatography on DEAE-Sepharose, Q-Sepharose, phenyl-Sepharose and Mono Q. The native protein showed a molecular mass of 350 kDa by gel filtration, whereas SDS/PAGE analysis provided a molecular mass of 44 kDa, indicating that D-gluconate dehydratase is an octameric protein. The enzyme showed maximal activity at temperatures between 80 and 90 °C and pH values between 6.5 and 7.5, and a half-life of 40 min at 100 °C. Bivalent metal ions such as Co2+, Mg2+, Mn2+ and Ni2+ activated, whereas EDTA inhibited the enzyme. A metal analysis of the purified protein revealed the presence of one Co2+ ion per enzyme monomer. Of the 22 aldonic acids tested, only D-gluconate served as a substrate, with Km=0.45 mM and Vmax=0.15 unit/mg of enzyme. From N-terminal sequences of the purified enzyme, it was found that the gene product of SSO3198 in the S. solfataricus genome database corresponded to D-gluconate dehydratase (gnaD). We also found that the D-gluconate dehydratase of S. solfataricus is a phosphoprotein and that its catalytic activity is regulated by a phosphorylation–dephosphorylation mechanism. This is the first report on biochemical and genetic characterization of D-gluconate dehydratase involved in the non-phosphorylated Entner–Doudoroff pathway.

Is Endoscopic Assessment of the Esophagus and Stomach Enough to Determine the Need for Biopsy at These Sites in Pediatric Patients Undergoing Endoscopy for Elevated TTG?

2021 ◽  
pp. 109352662199148
Author(s):  
M. Cristina Pacheco ◽  
Nicole Green ◽  
Jane Dickerson ◽  
Dale Lee
Keyword(s):  
Sensitivity And Specificity ◽  
Pediatric Patients ◽  
Tissue Transglutaminase ◽  
Immunoglobulin A ◽  
High Specificity ◽  
Visual Assessment ◽  
Pathology Report ◽  
Low Sensitivity ◽  
Endoscopic Assessment

Objectives The goal of our study was to determine whether visual assessment of the esophagus and stomach could predict abnormal histology and determine the frequency of interventions based on biopsies in patients undergoing endoscopy for elevated tissue transglutaminase immunoglobulin A antibody (TTG). Methods Pathology records were searched for patients with biopsy performed for elevated TTG. Pathology report, endoscopy report, and follow-up were obtained and slides from the duodenum reviewed. Pathology was considered gold standard for sensitivity and specificity calculations. Results 240 patients were included. 215 patients had esophageal biopsies performed. Esophageal endoscopic visual assessment had sensitivity of 47% and specificity of 93% for abnormal histology. 16(7%) patients had therapy or referral related to results and, of these, 6(38%) had visually normal endoscopy. 237 biopsies were performed of stomach. Gastric endoscopic visual assessment had a sensitivity and specificity of 20% and 87%. 24(10%) patients had therapy based on findings and, of these, 12 (50%) had visually normal endoscopy. Conclusions Endoscopic assessment of esophagus and stomach has low sensitivity and high specificity for pathologic abnormalities when indication for endoscopy is elevated TTG. When endoscopy is visually normal clinical interventions based on biopsy are rare, and foregoing biopsy may be considered.

A metalloproteinase extracellularly released byCrithidia deanei

2003 ◽  
Vol 49 (10) ◽  
pp. 625-632 ◽  
Author(s):  
Claudia Masini d'Avila-Levy ◽  
Rodrigo F Souza ◽  
Rosana C Gomes ◽  
Alane B Vermelho ◽  
Marta H Branquinha
Keyword(s):  
Molecular Mass ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Residual Activity ◽  
Major Protein ◽  
Motile Cells ◽  
Sds Page ◽  
Triton X

Actively motile cells from a cured strain of Crithidia deanei released proteins in phosphate buffer (pH 7.4). The molecular mass of the released polypeptides, which included some proteinases, ranged from 19 to 116 kDa. One of the major protein bands was purified to homogeneity by a combination of anion-exchange and gel filtration chromatographs. The apparent molecular mass of this protein was estimated to be 62 kDa by sodium dodecyl sulfate – polyacrylamide gel electrophoresis (SDS–PAGE). The incorporation of gelatin into SDS–PAGE showed that the purified protein presented proteolytic activity in a position corresponding to a molecular mass of 60 kDa. The enzyme was optimally active at 37 °C and pH 6.0 and showed 25% of residual activity at 28 °C for 30 min. The proteinase was inhibited by 1,10-phenanthroline and EDTA, showing that it belonged to the metalloproteinase class. A polyclonal antibody to the leishmanial gp63 reacted strongly with the released C. deanei protease. After Triton X-114 extraction, an enzyme similar to the purified metalloproteinase was detected in aqueous and detergent-rich phases. The detection of an extracellular metalloproteinase produced by C. deanei and some other Crithidia species suggests a potential role of this released enzyme in substrate degradation that may be relevant to the survival of trypanosomatids in the host.Key words: endosymbiont, trypanosomatid, extracellular, proteinase.

A prospective study of an AI-based breast cancer screening solution for resource-constrained settings.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e13586-e13586
Author(s):  
Richa Bansal ◽  
Bharat Aggarwal ◽  
Lakshmi Krishnan
Keyword(s):  
Breast Cancer ◽  
Cancer Screening ◽  
Breast Cancer Screening ◽  
Sensitivity And Specificity ◽  
Breast Tissue ◽  
Dense Breast ◽  
Resource Constrained ◽  
Dense Breast Tissue ◽  
Dense Breasts ◽  
Low Sensitivity

e13586 Background: Screening mammography is often found to have low sensitivity in women with high density breast tissues. Alternate modalities of breast USG and MRI require high-quality expensive equipment making the regular screening with these modalities less affordable and accessible, particularly in resource-constrained settings This study evaluates the clinical performance of an AI-based test (Thermalytix) that uses machine learning on breast thermal images which could potentially be a low-cost solution for breast screening in low- and middle-income countries (LMICs). Methods: The prospective comparative study conducted from December 2018 to January 2020 evaluated the performance of Thermalytix in women with dense and non-dense breast tissue who presented for a health check-up at a hospital. All women underwent Thermalytix and mammography. Further investigations were recommended for participants who were reported as positive on either test. Sensitivity and specificity of Thermalytix were evaluated across age-groups, menopausal status, and breast densities. Results: Among the 687 women recruited for the study, 459 women who satisfied the inclusion criteria were included in the analysis. 168 women had ACR categories ‘c’ or ‘d’ dense breasts, of which 37 women had an inconclusive mammography report (BI-RADS 0). Overall, 21 women were detected with breast cancer in the study. Thermalytix demonstrated an overall sensitivity of 95.2% (95% CI, 76.1-99·9) and a specificity of 88.6% (95% CI, 85.2-91.4). Among women with dense breast tissue (n=168), Thermalytix showed a sensitivity of 100% (95% CI, 69.2-100) and a specificity of 81.7% (95% CI, 74.7-87.4). In women with ACR categories ‘c’ and ‘d’ dense breasts, mammography reported 22% of them as inconclusive (BI-RAD 0), while in the same sub-set of the population Thermalytix demonstrated a sensitivity of 100%. Conclusions: The AI-based Thermalytix demonstrated high sensitivity and specificity in the study cohort. It also fared well in women younger than 50 years and pre-menopausal women where routine mammography screening yields low sensitivity. Overall, this study introduces Thermalytix, a promising radiation-free, automated, and privacy-aware test that can supplement mammography for routine screening of women, especially in women with dense breast tissue, and has the potential to influence the clinical practice in LMICs by making breast cancer screening portable and affordable. Performance of Thermalytix and mammography in women with high breast densities (ACR categories ‘c’ and ‘d’ breasts). Clinical trial information: NCT04688086. [Table: see text]

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