Learning gross anatomy: Dissection and prosection

The gross anatomy course at St. Louis University School of Medicine consists of 40 regions or units covering the entire body and utilizes peer teaching in which students do every fourth dissection. One-fourth of the students learn each unit by dissecting; three-fourths learn from predissected material. Four multiple choice tests were studied to determine whether students scored better on questions on units they dissected than those who learned from predissected material. Results were adjusted on the basis of students' scores on whole tests. There were four teams of students and four tests resulting in 16 sets of questions. Dissectors scored better than nondissectors in 13 sets, but the overall differences were small (67.80 vs. 66.70). It is concluded that there is a small advantage gained from dissecting and demonstrating to their peers, but that learning from dissected cadavers is a satisfactory method of study, since our students traditionally score above the national average on the anatomy portion of the National Board Examination. Clin. Anat. 9:57–59, 1996. © 1996 Wiley-Liss, Inc.     

A matrix metalloproteinase–generated aggrecan neoepitope as a marker of skeletal maturation and aging in cartilage

Objective. To quantify the matrix metalloproteinase–induced neoepitope F(M/V)DIPEN (Phe–[Met/Vall]-Asp–Jle–Pro–Glu–Asn³⁴¹) in guinea pig and rabbit cartilage during aging. Methods. Cartilage was taken from the stifle joint, nasal septum, and xiphoid process in guinea pigs and rabbits at selected ages. The cartilage was then extracted and evaluated for F(M/V)DIPEN levels by radioimmunoassay. Results. In the 3 tissues studied, there were major increases in F(M/V)DIPEN levels during skeletal maturation and aging in both the guinea pig and rabbit cartilage. Except for spontaneous osteoarthritis that develops in guinea pigs with aging, increases in the neoepitope were not correlated with arthritis pathology. Conclusion. Increases in the level of F(M/V)-DIPEN in cartilage occur as a result of skeletal maturation and aging. This physiologic accumulation of F(M/V)DIPEN in cartilage should be considered when using the neoepitope as a disease marker in arthritis.     

The role of hla antigens as indicators of disease progression in psoriatic arthritis

Objective. To identify HLA markers for the development of severe disease in psoriatic arthritis (PsA). Methods. Patients with PsA who were followed up prospectively over a 14-year period were included. Clinical and laboratory assessments of both active inflammation and clinical damage were performed at 6-month intervals according to a standard protocol, which also included serologic HLA typing for class I and II antigens. Progression of damage was defined as transition into higher damage states, defined by the number of damaged joints. Both univariate and multivariate models were developed to identify predictors for progression of damage. Results. Univariate analysis revealed that the HLA antigens B27, B39, and DQw3 were associated with disease progression, while HLA-DR7 was “protective.” The best multivariate model identified the HLA antigens B27, when DR7 was present, and DQw3, when DR7 was not present, as predicting disease progression across all transitions, while HLA-B39 was associated with progression in early disease. The addition of these HLA indicators to a model containing clinical variables resulted in a significant improvement in fit. Conclusion. The HLA antigens associated with PsA, B27 and B39, are risk factors for disease progression, as is the HLA class II antigen DQw3. In combination with clinical measures of disease, these HLA variables are the dominant predictors of progression.     

Voxel-based analysis of MRI detects abnormal visual cortex in children and adults with amblyopia

Amblyopia, sometimes called "lazy eye," is a relatively common developmental visual disorder well characterized behaviorally; however, the neural substrates associated with amblyopia in humans remain unclear. We hypothesized that abnormalities in the cerebral cortex of subjects with amblyopia exist, possibly as a result of experience-dependent neuronal plasticity. Anatomic magnetic resonance imaging (MRI) and psychophysical vision testing was carried out on 74 subjects divided into two age ranges, 7-12 years and 18-35 years, and three diagnoses, strabismic amblyopia, anisometropic amblyopia, and normal vision. We report a behavioral impairment in contrast sensitivity for subjects with amblyopia, consistent with previous reports. When the high-resolution MRI brain images were analyzed quantitatively with optimized voxel-based morphometry, results indicated that adults and children with amblyopia have decreased gray matter volume in visual cortical regions, including the calcarine sulcus, known to contain primary visual cortex. This finding was confirmed with a separate region-of-interest analysis. For the children with amblyopia, additional gray matter reductions in parietal-occipital areas and ventral temporal cortex were detected, consistent with recent reports that amblyopia can result in spatial location and object processing deficits. These data are the first to provide possible neuroanatomic bases for the loss of binocularity and visual sensitivity in children and adults with amblyopia.     

Phenotypic expansion of POGZ‐related intellectual disability syndrome (White‐Sutton syndrome)

White‐Sutton syndrome (WHSUS) is a recently‐identified genetic disorder resulting from de novo heterozygous pathogenic variants in POGZ. Thus far, over 50 individuals have been reported worldwide, however phenotypic characterization and data regarding the natural history are still incomplete. Here we report the clinical features of 22 individuals with 21 unique loss of function POGZ variants. We observed a broad spectrum of intellectual disability and/or developmental delay with or without autism, and speech delay in all individuals. Other common problems included ocular abnormalities, hearing loss and gait abnormalities. A validated sleep disordered breathing questionnaire identified symptoms of obstructive sleep apnea in 4/12 (33%) individuals. A higher‐than‐expected proportion of cases also had gastrointestinal phenotypes, both functional and anatomical, as well as genitourinary anomalies. In line with previous publications, we observed an increased body mass index (BMI) z‐score compared to the general population (mean 0.59, median 0.9; p 0.0253). Common facial features included microcephaly, broad forehead, midface hypoplasia, triangular mouth, broad nasal root and flat nasal bridge. Analysis of the Baylor Genetics clinical laboratory database revealed that POGZ variants were implicated in approximately 0.14% of cases who underwent clinical exome sequencing for neurological indications with or without involvement of other body systems. This study describes a greater allelic series and expands the phenotypic spectrum of this new syndromic form of intellectual disability and autism.     

Health literacy among cancer survivors: Results from the 2016 behavioral risk factor surveillance system survey

Health literacy is a set of knowledge and skills that enables individuals to obtain, communicate, process and understand information, and services to make appropriate health decisions and to successfully navigate the health care system. Health literacy is important to quality of cancer survivorship care and patient self-management of their disease.We examined health literacy among cancer survivors, using data from the 2016 Behavioral Risk Factor Surveillance System. We compared health literacy across various demographic and socioeconomic groups and estimated the adjusted odds in favor of low health literacy for these characteristics.We found that about 16% of the cancer survivors had low health literacy. The prevalence was higher among Hispanic and Black individuals, and among those with poor health status, low income and educational attainment.A sizeable percentage of cancer survivors have low health literacy which is likely to complicate their ability to self-manage their disease and navigate the health care system for optimal care. In order to ensure the quality and appropriateness of cancer survivorship care, effective interventions are needed to address low health literacy in these populations.     

Retrievable Inferior Vena Cava Filters: Initial Clinical Results

Anticoagulation is the accepted therapy for patients with thromboembolic disease. When contraindications to anticoagulant therapy are present, however, interruption of the inferior vena cava (IVC) may prevent pulmonary embolism (PE). The objective of this study was to report our early technical and clinical results with retrievable IVC filters (IVCFs) for the prevention of PE. One hundred and twenty-seven multitrauma patients between December 1, 2002, and December 31, 2004, underwent placement of Gunther-Tulip (n = 49), Recovery (n = 41), or OptEase (n = 37) retrievable IVCFs under real-time intravascular ultrasound (IVUS) guidance. All patients had abdominal X-rays to verify filter location. Prior to IVCF retrieval, all patients underwent femoral vein color flow ultrasonography to rule out deep vein thrombosis (DVT) and vena-cavography to assess the IVCF for trapped emboli, filter tilt, or retrained thrombus. Thirty-nine patients died of their injuries; no deaths were related to IVCF placement. One PE occurred during follow-up after filter retrieval, and two femoral vein insertion-site DVTs occurred. One hundred twenty (94.4%) of IVCFs were placed without complication at the L2-3 level, as verified by abdominal X-rays. Filter-related complications included three groin hematomas (2.9%) and three IVCFs misplaced in the right iliac vein early in our experience (2.3%); these filters were uneventfully retrieved and replaced in the IVC within 24 hr. Sixty-six patients underwent uneventful retrieval of IVCFs after DVT or PE anticoagulation prophylaxis was initiated. Forty-five IVCFs were not removed: 41 due to contraindications due to anticoagulation and four because of trapped thrombus within the filter. The role of retrievable IVCFs continues to evolve, but in this study of 127 patients, prophylactic temporary IVCF placement was simple and safe, prevented fatal PE, and served as an effective “bridge” to anticoagulation. Further investigation of this bedside IVUS technique and the role of temporary IVCFs in different patient populations is warranted. SECTION EDITOR: Samuel S. Ahn, MD     

Human blood PIG-A mutation and micronucleated reticulocyte flow cytometric assays: Method optimization and evaluation of intra- and inter-subject variation

We previously described flow cytometry-based methods for scoring the incidence of micronucleated reticulocytes (MN-RET) and PIG-A mutant phenotype reticulocytes (MUT RET) in rodent and human blood samples. The current report describes important methodological improvements for human blood analyses, including immunomagnetic enrichment of CD71-positive reticulocytes prior to MN-RET scoring, and procedures for storing frozen blood for later PIG-A analysis. Technical replicate variability in MN-RET and MUT RET frequencies based on blood specimens from 14 subjects, intra-subject variability based on serial blood draws from 6 subjects, and inter-subject variation based on up to 344 subjects age 0 to 73 years were quantified. Inter-subject variation explained most of the variability observed for both endpoints (≥77%), with much lower intra-subject and technical replicate variability. The relatively large degree of inter-subject variation is apparent from mean and standard deviation values for MN-RET (0.15 ± 0.10%) and MUT RET (4.7 ± 5.0 per million, after omission of two extreme outliers). The influences of age and sex on inter-subject variation were investigated, and neither factor affected MN-RET whereas both influenced MUT RET frequency. The lowest MUT RET values were observed for subjects <11 years old, and males had moderately higher frequencies than females. These results indicate that MN-RET and MUT RET are automation-compatible biomarkers of genotoxicity that bridge species of toxicological interest to include human populations. These data will be useful for appropriately designing future human studies that include these biomarkers of genotoxicity, and highlight the need for additional work aimed at identifying the sources of inter-individual variability reported herein.