Evaluation of an enzyme-linked binding protein assay for hyaluronic acid and concentrations in hepatitis C infected patients

PosterSerological hyaluronic acid (HA) has been proposed as a noninvasive alternative to liver biopsy for assessing the extent of liver fibrosis. Liver biopsy correctly identifies hepatic disease in about 65 to 75% of cases, being strongly dependent on the length of the biopsy obtained. Furthermore, hepatic fibrosis is often not distributed homogeneously throughout the liver. In contrast, studies suggest HA to have better sensitivity and specificity with areas under receiver operating curves of 0.86 and 0.92, and negative predictive values of 93% and 99% for fibrosis and cirrhosis respectively. Moreover, the non-uniform distribution of hepatic fibrotic tissue does not affect HA results. In this study, we evaluated and validated a commercially available enzyme-linked binding protein assay for measuring HA. We also investigated serum/plasma HA concentrations in subjects having elevated levels of hepatitis C virus (HCV) RNA. The HA assay (Corgenix Inc., Westminster, CO) is a spectrophotometric sandwich protein binding assay in microplate format. The test utilizes a highly specific HA binding protein (HABP) coated to the microwell surface to capture HA. An enzyme conjugated version of HAPB is subsequently used to detect the HA in the sample. The assay uses six calibrators with final results expressed as ng HA/mL. Serum and/or plasma samples were stored and assayed according to the kit manufacturer's instructions. The assay's limit of detection was 8 ng/mL resulting in an analytical measurement range of 8 - 800 ng/mL. A linearity study spanning this range generated a slope of 1.008, intercept of 13.64 and R2 of 0.998 (n = 7). The within-run precision at three levels (n = 8) was determined to be 29 ? 0.8, 138 ? 3.4 and 546 ? 6.7 ng/mL with CVs of 2.7, 2.5 and 1.2% respectively. Between-run precision at three levels (n = 7) resulted in values of 44? 3.9, 87? 7.6 and 459? 29.3 ng/mL generating CVs of 8.8, 8.5 and 6.4% respectively. A correlation study using samples previously assayed at Corgenix produced a slope, intercept and R2 of 0.957 -0.56 and 0.993 respectively as analyzed by Deming Regression (n = 22, range 29 - 866 ng/mL). Utilizing donations from 122 healthy individuals, an upper 97.5% reference limit of 54 ng/mL was established. HA was found stable for 24 hours at room temperature, and a minimum of two weeks at 4?C. Deidentified serum or plasma samples from patients with HCV infection were assayed for HA. These patients had HCV RNA levels greater than log 2.3 IU/mL as previously measured by real-time polymerase chain reaction. Of 68 specimens, 53% (36) were found to have elevated HA, with concentrations greater than 37 ng/mL. HA concentration did not correlate with HCV RNA level. In conclusion, the Corgenix HA test kit has shown acceptable performance characteristics for quantifying HA. Although the stages of liver fibrosis for the HCV infected subjects in this study were unavailable, the large percentage having elevated HA supports previous studies suggesting the possible use of HA in assessing liver fibrosis and/or cirrhosis in lieu of liver biopsy

The Effect of Maternal Hypoxia on Metanephric Development in the Hamster

Thesis (Ph.D)--Boston UniversitySixty-six non-pedigreed gravid albino hamsters (Mesocricetus auratus) were exposed to a single dose of hypoxia of five to ten hours duration between the seventh and tenth days of gestation in order that the period during which the embryonic excretory system is most sensitive to the action of the teratogen might be determined. Maximum sensitivity occurred during the 10 hour interval between 1:30 - 11:30 a.m. on the 8th day of development (post ovulatory) which is coincident with the period of most rapid differentiation, morphogenesis, and changes in body form (twisting and flexing). The oxygen pressure was equivalent to 40.5 to 48.6 mm. Hg or 25.5 to 30.6 percent of normal atmospheric oxygen. Hypoxia was effected by use of an improvised altitude chamber consisting of two large-sized dessicating jars, a supply of compressed air, a vacuum pump, and a mercury manometer. The reduction of atmospheric pressure was approximately that found at an altitude of 30,500 feet. Three hundred and five embryos were examined for gross abnormalities after 15-16 days of development. One hundred eighteen embryos were sacrificed between 9 1/2 - 12 1/2 days of gestation and examined histologically for abnormalities of the developing excretory system. The array of congenital abnormalities detected was related to the time and duration of exposure of the maternal organism to the hypoxic insult. Mortality and morbidity rates increased as the duration of hypoxia increased. Abnormalities identified included exencephalocoel, micrognatha, hare-lip, vertebral and rib defects, limb abnormalities, cryptorchidism, renal defects, hydroureter, uterine aplasia, herniated diaphragm, abnormal spinal cord, and one instance of a double testis on one side. The renal defects included renal agenesis, discontinuity of the mesonephric duct, premature and ectopic termination of the mesonephric duct, development of accessory ducts from the mesonephric duct, multiple metanephric pelves forming about combinations of accessory ducts, mesonephric duct and ureteric buds, and malpositioning of the metanephroi. Evidence is presented to indicate that the mesonephric duct of the hamster grows by elongation of a growing tip rather than by accretion of new cells from the urogenital ridge during its posterior development. The mesonephric duct, accessory ducts (elongate diverticulae from the mesonephric ducts in areas other than that which normally gives rise to the ureter), and the ureteric tip are all capable of inducing development of the metanephric blastema. It is proposed that the collecting ducts of the chick mesoenprhos are homologous with the accessory ducts and the ureteric buds of the mammal. The abnormalities of development of the mesonephric duct are believed to be due to inhibition of growth and/or differentiation and the incompatibility of localized areas of development with normal mesonephrogenic tissue. It is postulated that normal surface related phenomena involved in cell migration or guidance systems have been interrupted. It is proposed that this may be the result of simple retardation of development, inability of the embryo to complete appropriate biochemical syntheses, or accumulation of toxic substances. Alteration in permeability of placental blood vessels might also be a complicating factor. It is suggested that the use of non-pedigreed animals with genetic parameter limited only by the similarity in coat color has possibly afforded a greater variety of effect than would have been obtained under more closely controlled genetic conditions. [TRUNCATED

Humananti-mouse antibody protected ELISA for the quantification of squamous cell carcinoma antigen

ReportSquamous cell carcinoma antigen (SCC) was first isolated from squamous cell carcinoma tissue of the uterine cervix and initially reported as TA-4. The antigen has been characterized as a glycoprotein with a molecular weight between 45,000 and 55,000 daltons. Studies suggest that SCC may function as a protease inhibitor.SCC is expressed in normal epithelium and epithelial tissues. The antigen primarily consists of over ten protein fractions with isoelectric points ranging from 5.9 to 6.6 which are generally divided into two groups: The acidic group with isoelectric points Despite the demonstrated clinical utility of SCC testing, reagents (investigational use only) were no longer available in the US by the late 1990s. Yet, SCC testing continues to be commercially available in Europe and Asia. We therefore, have developed and validated a 96-well microtiter plate formatted ELISA as an option for SCC testing. The ELISA includes protection against human anti-mouse antibodies (HAMA) to a theoretical limit of at least 3.2 mg/mL

Evaluation of a fecal pancreatic elastase-1 enzyme-linked immunosorbent assay: assessment versus an established assay and implication in classifying pancreatic function

ManuscriptDisagreement continues regarding the two commercially available fecal pancreatic elastase-1 (PE-1) ELISAs and their respective capabilities to assess pancreatic function. Our objectives were to validate the newer PE-1 ELISA and evaluate the test against the previously established assay, to investigate the PE-1 correlation with fecal fat, and examine the PE-1 result distribution of clinical specimens. Methods: The BioServ Diagnostics PE-1 ELISA was validated and performance characteristics compared to the previously validated ScheBo(R) Biotech PE-1 ELISA. A split sample study was accomplished using Deming regression and Bland-Altman plot analysis. Data mining was implemented to evaluate PE-1 and fecal fat correlation, and to explore PE-1 result distribution. Results: Regression analysis shows limited quantitative agreement; slope = 0.9640, intercept = 10.787, R2 = 0.633. The means were 228.8 and 226.2 μg PE-1/g stool for the BioServ and ScheBo assays respectively. Bland-Altman analysis indicated 91% of paired values within two standard deviations of their means (100% within 2.2 standard deviations). There was good qualitative agreement between assays with 91% of cases having equivalent pancreatic function classification. The remaining 9% varied by only one classification level with no bias towards either test evident. The distribution of typical clinical specimens for infants through young adults is dichotomous, with few subjects classified with moderate pancreatic insufficiency. There is minimal agreement between PE-1 and fecal fat. Conclusions: The BioServ Diagnostics PE-1 ELISA is an acceptable alternative to the ScheBo Biotech PE-1 ELISA. We also recommend that PE-1 replace fecal fat analysis for the evaluation of pancreatic function

Human Learning, Memory, and Student Development

My educational interests have largely been informed by my career in the sciences and medicine. My professional education has been both formative and transformative, opening doors to the joy of learning and a realization in the importance of memory. As an educator, clinician, and student, I have been greatly impacted by issues of curricular design, curricular development, learning and memory. My current responsibilities in student affairs also have exposed me to the delicate balance between student development, curricular design, learning and memory. Patton, Renn, Guido, and Quaye (2016) noted the importance of educators being able to use different literature sources and concepts in their daily interactions with students. In addition, Patton et al. (2016) further emphasized the importance of literature in guiding professionals in the development of curricular and related policy changes. Underpinning student development issues is the notion that the goals of education are ultimately tied to memory and learning. Atkinson and Shiffrin (2016) noted that “it is hard to imagine how understanding memory could not be important….memory is what we are, and what defines us as individuals” (p. 115). Atkinson and Shiffrin (2016) further noted how our memory system is divided into structural components and processing components that work together to create a retrievable memory. This simple fact has played out in my professional life as I have provided care for patients with dementia or other memory destroying processes; witnessing the person, father, mother, brother, sister, son, daughter, and friend literally become unrecognizable cognitively. In higher education we understand that learning and memory are symbiotic but not synonymous. Illeris (2018) noted that learning can be defined broadly as any process that leads to “change” and is not solely related to maturation or aging (p. 7). In higher education however, we are more interested in managing student education through the manipulation of learning acquisition and student-environment interactions (Illeris, 2018). Memory is an ill-defined event, which happens in our brain, and is impacted by many external factors (Roediger & Wertsch, 2008). In this paper I will explore issues of student development, human learning, human memory, and how these concepts should inform higher education’s approach to curricular issues and design. I will explore unique learning and memory concepts to provide a better understanding of the many facets of memory and learning. Additionally, I will survey ideas on curricular design that could incorporate important learning and memory concepts

Patient-specific instrumentation in total knee arthroplasty provides no improvement in component alignment

pre-printImproved component alignment in TKA remains a commonly cited benefit of MRI based patient-specific instrumentation (PSI). We hypothesized that PSI would lead to improved alignment versus traditional instrumentation (TI) during primary TKA. Fifty-eight knees (54 patients) that underwent TKA with PSI were compared to 62 knees that had previously undergone TKA with TI. Radiographs were evaluated for mechanical axis and alignment of the femoral and tibial components. Alignment was similar between the groups. However, the PSI group showed fewer knees in the target range for posterior tibial slope (PSI 38% vs. TI 61%, p=0.01) in addition to a trend for fewer knees in target for femoral flexion (PSI 40% vs. TI 56%, p=0.07). This study demonstrated no improvement in overall alignment and perhaps a worsening of the tibial slope

The use of a modular titanium baseplate with a press-fit keel implanted with a surface cementing technique for primary total knee arthroplasty

pre-printLittle data exists regarding outcomes following TKA performed with surface-cementation for the fixation of modular tibial baseplates with press-fit keels.Thus, we retrospectively reviewed the clinical and radiographic outcomes of 439 consecutive primary TKAs performed with surface cemented tibial components. There were 290 female patients and 149 male patients with average age of 62 years (range 30-84). Two tibial components were revised for aseptic loosening (0.5%) and four tibial components (0.9%) were removed to improve instability ( = 2) or malalignment ( = 2). Complications included 13 deep infections treated with 2-stage revision (12) and fusion (1). These results support the surface cement technique with a modular grit-blasted titanium surface and cruciform stem during primary TKA