Search

Purpose: A mixed-method approach was used to investigate the lived experiences of adults with mild traumatic brain injury (mTBI). The study aimed to understand the perceived relationship between cognitive-communication problems, thinking and communication concerns, and neurobehavioral symptoms. We hypothesized that individuals with cognitive-communication problems would attribute their problems with communication to their mTBI history and their self-perceived problems would be correlated with symptomatology. Method: The Neurobehavioral Symptom Inventory (NSI) and an online cognitive-communication survey was used to conduct a study of 30 adults with mTBI history. Quantitative survey and NSI scores were analyzed with content analysis and correlational statistics. Results: The average NSI Total score was 17 with the following subscale scores: somatic (5), affective (8), and cognitive (3.9). Participants reported problems with expressive communication (56%), comprehension (80%), thinking (63%), and social skills (60%). Content analysis revealed problems in the following areas: expression (e.g., verbal, and written language), comprehension (reading and verbal comprehension), cognition (e.g., attention, memory and speed of processing, error regulation), and functional consequences (e.g., academic work, social problems, and anxiety and stress). A Pearson correlation indicated a statistically significant relationship ( p < .01) between the Communication Survey Total and the Total, Somatic, Affective, and Cognitive subscales. Conclusions: This study highlights a multifactorial basis of cognitive-communication impairment in adults with mTBI. We show that those with mTBI history perceive difficulties with cognitive-communication skills: conversations, writing, and short-term memory/attention. Furthermore, those with mTBI perceive their cognitive-communication problems after injury have impacted their vocational, social, and academic success.

Purpose Triple negative breast cancer (TNBC) is an aggressive breast cancer subtype that disproportionately affects women of African ancestry (WAA) and is often associated with poor survival. Although there is a high prevalence of TNBC across West Africa and in women of the African diaspora, there has been no comprehensive genomics study to investigate the mutational profile of ancestrally related women across the Caribbean and West Africa. Methods This multisite cross-sectional study used 31 formalin-fixed paraffin-embedded (FFPE) samples from Barbadian and Nigerian TNBC participants. High-resolution whole exome sequencing (WES) was performed on the Barbadian and Nigerian TNBC samples to identify their mutational profiles and comparisons were made to African American, European American and Asian American sequencing data obtained from The Cancer Genome Atlas (TCGA). Whole exome sequencing was conducted on tumors with an average of 382 × coverage and 4335 × coverage for pooled germline non-tumor samples. Results Variants detected at high frequency in our WAA cohorts were found in the following genes NBPF12, PLIN4, TP53 and BRCA1. In the TCGA TNBC cases, these genes had a lower mutation rate, except for TP53 (32% in our cohort; 63% in TCGA-African American; 67% in TCGA-European American; 63% in TCGA-Asian). For all altered genes, there were no differences in frequency of mutations between WAA TNBC groups including the TCGA-African American cohort. For copy number variants, high frequency alterations were observed in PIK3CA, TP53, FGFR2 and HIF1AN genes. Conclusion This study provides novel insights into the underlying genomic alterations in WAA TNBC samples and shines light on the importance of inclusion of under-represented populations in cancer genomics and biomarker studies.

Accurate transcription is required for the faithful expression of genetic information. However, relatively little is known about the molecular mechanisms that control the fidelity of transcription, or the conservation of these mechanisms across the tree of life. To address these issues, we measured the error rate of transcription in five organisms of increasing complexity and found that the error rate of RNA polymerase II ranges from 2.9 × 10−6 ± 1.9 × 10−7/bp in yeast to 4.0 × 10−6 ± 5.2 × 10−7/bp in worms, 5.69 × 10−6 ± 8.2 × 10−7/bp in flies, 4.9 × 10−6 ± 3.6 × 10−7/bp in mouse cells and 4.7 × 10−6 ± 9.9 × 10−8/bp in human cells. These error rates were modified by various factors including aging, mutagen treatment and gene modifications. For example, the deletion or modification of several related genes increased the error rate substantially in both yeast and human cells. This research highlights the evolutionary conservation of factors that control the fidelity of transcription. Additionally, these experiments provide a reasonable estimate of the error rate of transcription in human cells and identify disease alleles in a subunit of RNA polymerase II that display error-prone transcription. Finally, we provide evidence suggesting that the error rate and spectrum of transcription co-evolved with our genetic code.

The Change Laboratory methodology offers the potential to support expansive learning in preservice bilingual teacher education. This qualitative case study examines how ten preservice Chinese and K...

This paper adapts a ‘sense of place’ framework to investigate varying preferences for the physical and cultural offerings of arts centres using a choice experiment. An on-site survey was conducted ...

This qualitative case study is an examination of the relational agency manifested by three Chinese preservice bilingual teachers as they participated in a semester-long Change Laboratory (CL) inter...

This qualitative case study explores how raciolinguistic ideology of Chinese heritage is collectively shaped in first-year non-heritage Mandarin classes in one US university, but individually told by two minoritized (ethnolinguistically marginalized) heritage learners and two non-heritage learners. Their experiences in learning Mandarin Chinese as a non-heritage language elucidate how Chinese language learners negotiate their ethnolinguistic identities in the transnational world. The stories of four Chinese language learners demonstrate how their raciolinguistic ideology is collectively shaped by a complex racialization process while negotiating their race, ethnicity, culture, language, and transnationality. The present study challenges the raciolinguistic ideologies of the institutionalized norms of defining heritage and non-heritage learners as learner-trait terms. Implications for researchers and practitioners of Language Learning Centers beyond US higher education are drawn.

With the lack of ethnolinguistic-specific resources for U.S. teachers, this essay is written for teachers working with ethnolinguistic students at schools and in the communities. In what follows, I...

The demographic change of Chinese bilingual preservice teachers (herein referred to as trainees) has caused a shift in the practitioner populations in the US This qualitative case study reports on ...

Accurate transcription is required for the faithful expression of genetic information. Surprisingly though, little is known about the molecular mechanisms that control the fidelity of transcription, or the conservation of these mechanisms across the tree of life. To address this issue, we measured the error rate of transcription in five organisms of increasing complexity and identified various genes, alleles and processes that control transcriptional fidelity in multicellular organisms. In doing so, they highlight the evolutionary conservation of fidelity factors and open up new opportunities to probe the impact of transcription errors on intact organisms and human physiology. Finally, our experiments provide the first reasonable estimate of the error rate of transcription in human cells, identify the first disease associated with error-prone RNA polymerases and suggest that transcription errors may have contributed to the evolution of our genetic code.

Background: Orofacial clefts (OFCs) are common congenital disabilities that can occur as isolated non-syndromic events or as part of Mendelian syndromes. OFC risk factors vary due to differences in regional environmental exposures, genetic variants, and ethnicities. In recent years, significant progress has been made in understanding OFCs, due to advances in sequencing and genotyping technologies. Despite these advances, very little is known about the genetic interplay in the Malagasy population. Methods: Here, we performed high-resolution whole-exome sequencing (WES) on non-syndromic cleft lip with or without palate (nCL/P) trios in the Malagasy population (78 individuals from 26 families (trios)). To integrate the impact of genetic ancestry admixture, we computed both global and local ancestries. Results: Participants demonstrated a high percentage of both African and Asian admixture. We identified damaging variants in primary cilium-mediated pathway genes WNT5B (one family), GPC4 (one family), co-occurrence in MSX1 (five families), WDR11 (one family), and tubulin stabilizer SEPTIN9 (one family). Furthermore, we identified an autosomal homozygous damaging variant in PHGDH (one family) gene that may impact metabiotic activity. Lastly, all variants were predicted to reside on local Asian genetic ancestry admixed alleles. Conclusion: Our results from examining the Malagasy genome provide limited support for the hypothesis that germline variants in primary cilia may be risk factors for nCL/P, and outline the importance of integrating local ancestry components better to understand the multi-ethnic impact on nCL/P.

With the recent global pandemic, education institutions including higher education have shifted to offering online instruction for a prolonged period of time. Faculty and instructors have had to transform the content of face-to-face instruction into a format fit for distance education. In the virtual space, understanding or facilitating interactivity is a key component of online teaching for sustaining engagement and social interactions; promoting active learning between participants; and providing resources, tasks, and activities. The learning management system as a facilitative boundary object makes pivoting to online classes more tactical when adopting cultural-historical activity theory as an analytical lens, which can be used as a guide to re-envision how interactions can be implemented in e-learning or online courses and how instructors can repurpose resources and tools to maximize their instructional practices. Examples of interactivity and the implications for practitioners are synthesized, and the multiple components at play in the online and hybrid space are characterized in order to promote the exchange of practices and knowledge mobilization.

Objective Comprehensive molecular profiling of radioresistant and cystic vestibular schwannoma (VS) subtypes. Study design Our study utilized whole-exome sequencing (WES), RNA-sequencing (RNAseq), and correlated clinical data from 12 samples (2 samples of solid sporadic subtype, 8 with cystic changes, and 2 previously irradiated). Setting Academic medical center. Patients Patients diagnosed with VS who required surgical treatment. Inclusion: Cystic and radioresistant tumors matched to age and tumor volume, with solid sporadic VS samples as control; Exclusion: NF-2 patients. Intervention(s) WES using custom probes for copy number analysis. A modified version of the Agilent Human Whole Exome sequencing hybrid capture system was used to process samples. Recurrent variants were identified and compared between groups. Leukocyte-derived DNA was utilized as internal control to reduce false-positives. Main outcome measure(s) Analysis of genetic landscape of VS subtypes (naive solid VS, cystic VS, and previously irradiated VS) by performing deep next-generation sequencing. Results WES data achieved a mean coverage of 202X and RNAseq generated an average of 74 million total reads. As a group, 25% of samples had 22q loss. Somatic analysis identified previously reported genes and multiple novel mutations across samples. Differential expression analysis of RNAseq data found significantly mutated genes such as COL6A3, CLMP, ART4, Lumican that were shared by both cystic VS and irradiated VS, but not seen in sporadic VS. Conclusions Using WES we were able to demonstrate that cystic and irradiated samples are subtypes of VS with an increased mutation burden and a unique genetic fingerprint. We identified differences between the genomic and molecular profile of cystic VS and radioresistant VS. Our results help advance the understanding of the pathophysiology of these tumor subtypes and suggest possible molecular targets for novel treatment strategies.

Dannelle D. Stevens is a scholarly mentor, academic cheerleader, and professor emerita at Portland State University (PSU) in Oregon. This book is a mentor-text that provides words of wisdom based o...

Women of African ancestry (WAA) are disproportionately affected by the aggressive triple negative breast cancer (TNBC) subtype that is often associated with high recurrence rates and metastasis. Although there is a high prevalence of TNBC across West Africa and in women of the African diaspora, there has been no comprehensive genomics study to investigate the mutational profile of ancestrally related women across the Caribbean and West Africa. To shed more light on this phenomenon, whole exome sequencing (WES) was performed on 31 formalin-fixed paraffin-embedded TNBC tissues from ancestrally related Barbadian and Nigerian women. We compared these genomics profiles with data from The Cancer Genome Atlas (TCGA) for African American (TCGA-AA), European American (TCGA-EA) women with TNBC. With an average coverage of 382x for tumour samples (n= 31) and 4335x for pooled germline (n=22) non-tumor samples, the most mutated genes in our cohorts include NBPF12, PLIN4, TP53 and BRCA1. For TCGA TNBC cases, these genes had a lower mutation rate, except for TP53 (32% in our cohort; 63% in TCGA-AA; 67% in TCGA-EA). For all altered genes, there were no differences in frequency of mutations between WAA TNBC groups including the TCGA-AA cohort. Additionally, we observed a high frequency of copy number variant alterations in PIK3CA, TP53, FGFR2 and HIF1AN genes. This study provides in-depth insights into the underlying genomic alterations in WAA-TNBC samples and shines light on the importance of inclusion of non-European populations in cancer genomics and biomarker studies. Citation Format: Shawn M. Hercules, Xiyu Liu, Blessing I. Bassey-Archibong, Desiree H.A. Skeete, Suzanne Smith Connell, Adetola Daramola, Adekunbiola A.F. Banjo, Godwin Ebughe, Thomas Agan, Ima-Obong Ekanem, Joe E. Udosen, Christopher Obiorah, Aaron C. Ojule, Michael A. Misauno, Ayuba M. Dauda, Ejike C. Egbujo, Jevon C. Hercules, Amna Ansari, Ian Brain, Christine MacColl, Yili Xu, Yuxin Jin, Sharon Chang, John D. Carpten, André Bédard, Gregory R. Pond, Kim R.M. Blenman, Zarko Manojlovic, Juliet M. Daniel. Analysis of the genomic landscapes of Barbadian and Nigerian women with triple negative breast cancer [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-142.

While many studies have identified the important aspects on the ship to cruisers, none has evaluated these attributes to determine cruisers’ willingness to pay for each attribute. This paper is the first to use a choice experiment to unbundle the overarching cruise price to explore the preferences of cruisers. The absence of a status quo effect suggests that cruise passengers are novelty lovers who welcome innovative offerings apart from those who cruise specifically to “get away”. Overall, males, Gen X-ers and first timers were willing to pay the most for a cabin with a view while the desire to be pampered influenced preferences for cabin comfort and shore excursion choice. Concern over value for money explained whether a respondent would be more prone to choosing the new options presented instead of remaining with the status quo.

This study examines some challenges and draws lessons for a new cultural city promoting an emerging festival. This was done by considering the valuation of the festival and its determinants by foreign tourists, domestic tourists, and potential attenders (a group often ignored in the literature). For a young festival, it was encouraging to find that the festival's social value to tourists, local attenders, and potential attenders exceeded the entry fee. Overall, the Biennale was more popular with younger people, and local attenders appreciated the educational dimension of the event. This augurs well for the future of this festival. However, for the festival's sustainability, it is important to strike a balance between catering to preferences of international and local attenders as well as avoid trying to achieve multiple objectives that may lead to a dilution in the focus and identity of the new festival.

Fifteen years ago a survey of Victorian public maternity services showed that the majority of services provided no fetal surveillance education to their staff and that only one in ten undertook any sort of assessment of staff knowledge. Today, all hospitals, public and private, provide training and all public hospitals require their midwifery and medical staff to undertake regular assessment of knowledge. The requirements of specialist obstetricians in private practice remain variable.

This study examines the value placed on museums by patrons and non-patrons and investigates the factors that affect this valuation with a view to boost visitorship. The total economic value of Singapore’s History Museum is at least US$57 million, and this is high relative to other countries, a fact which can be used to justify increased government funding towards museums as cultural capital. Females and high income people are the target groups for increased visitation, while among the non-patrons, the ethnic majority is another potential clientele. Somewhat surprising is the finding that neither patrons nor non-patrons see the museum as having significant tourist value, and contrary to prospect theory, there is a preference for enhancing the museum’s services over keeping the museum. These findings provide some direction for the management of the museum to improve its visitor appeal.

While the methodology of formative intervention research has long been established, the aspect of new instrumentality of Change Laboratory is fragmentally documented. Therefore, in this study, we modified two major Change Laboratory mediating tools used in bilingual student-teaching seminars, namely the disturbance diary and four-field model. These two empirically investigated Change Laboratory tools have mediated transformative agency within the collective movement toward identity formation as the Change Laboratory participants (bilingual preservice teachers) conveyed their dilemma of to-be or not-to-be a bilingual teacher. We provide evidence on the relationship between the bilingual preservice teachers’ identity formation and their participation in the Change Laboratory intervention. The analysis made salient the role of two new Change Laboratory mediating tools, the adapted disturbance diary and individually generated four-field models, for the bilingual preservice teachers’ collective transformation in bilingual teaching. It also crystallized the importance of deepening the bilingual preservice teachers’ analysis of multiple languages and pedagogy as understood in the new bilingual teaching model in the Change Laboratory intervention.

Introduction: Idiopathic erythrocytosis (IE) is characterized by a persistently elevated hemoglobin, equivocal erythropoietin (EPO) levels, absence of janus kinase 2 (JAK2) mutations suggestive of polycythemia vera (PV) and no secondary cause. One study used a targeted 21 gene next-generation sequencing panel and identified novel variants in known erythrocytosis-related genes as well as novel genes associated with the oxygen-sensing pathway. However, expanded sequencing of blood and matched tissue samples in a large ethnically diverse group of IE patients has not been performed. Methods: All patients signed informed consent to participate in an observational study approved by the Institutional Review Board; they provide blood and buccal mucosa samples at study entry and at 24-month follow-up. Patients were enrolled if JAK2 testing and a complete work up for secondary causes was negative. They were required to have hemoglobin levels greater than 16 g/dL on two occasions or greater than 15 g/dL if undergoing phlebotomy. Our initial sequencing of 20 IE patients was performed utilizing high resolution whole-exome sequencing of circulating blood samples (disease) at a mean coverage of 390x and matched normal (buccal) samples at mean coverage of 300x. To stratify samples by genetic ancestry, we performed a population stratification principle component analysis (PCA) and STRUCTURE using Ancestry Informative Markers derived from 1K Genome Phase1_v3 Exome database. The primary in-silico analysis was performed on the baseline samples from treatment-naïve patients. The whole-exome data was generated in accordance to GATK's best practices with same filters applied as described by Exome Aggregation Consortium. The additional downstream in-silico paired analysis was performed using MutSig2.0 (Mutation Significance) algorithm to determine significant mutations and GISTIC (The Genomic Identification of Significant Targets in Cancer) to identify the significant copy number events, IPA (Ingenuity Pathway Analysis) to determine pathways along with other computational . Results: Median age at baseline was 52 years (range 35-71). Six patients (30%) were female and 14 (70%) were male. Median values and ranges for laboratory parameters at baseline were as follows: WBC 6.6 x 109/L (5-9.7), Hgb 17 g/dL (15.5-19.8), Plt 218 x 109/L (86-374), and EPO level 9.8 IU/L (2-14.3). Three patients had a personal history of malignancy, including 2 with lymphoma. Two patients had a family history of myeloid malignancy (chronic myeloid leukemia and PV). Our ancestry analysis of initial 20 patients with IE identified 6 patients with high European percent ancestry (EUR), 1 patient with high Asian percent ancestry (EAS) and 13 patients with high percent Ad Mixed ancestry (AMR). In our cohort, 60% (12/20) of patients had been also diagnosed with a liver disorder (11 with fatty liver, 1 with cirrhosis) that was not significantly different across populations. We identified, on average, 42 non-silent somatic mutations (not present in the buccal samples) in whole blood across our cohort with no statistical difference (p=0.671) in mutation burden between ancestry groups or between patients with and without liver disease. Age, gender, and ethnicity were not associated with mutation burden. Utilizing MutSig algorithm, we identified a novel candidate gene, CHAF1A, with high mutation prevalence of 30% in patients with IE. Further analysis of mutation landscape identified somatic nonsilent mutations in 25 known oncogenes which were present in at least 10% of patients. Our mutation signatures in IE identified a significant association with failure of double stranded DNA repair. Only one patient had a mutation in TET2. Further analysis of copy number indicated copy number loss in genes such as SETD3 and GSH associated with chromatin assembly which may suggest alterations in chromatin assembly and changes in the epigenome. Our analysis also identified a high number of 9p and 13q gains in patients with IE. Conclusion: In this study, we utilized high-resolution next generation sequencing in association with comprehensive clinical annotation to determine potential molecular drivers of IE in a multi-ethnic population. We identified somatic mutations in a subset of patients which may represent clonal hematopoiesis. Long term follow up of outcomes in this cohort may clarify the significance of these mutations in the pathogenesis of IE. Disclosures No relevant conflicts of interest to declare.

Background: Tumor heterogeneity is a hallmark of cancer and can have significant impact on identifying drivers, including those that may be therapeutically relevant. Although, the traditional sequencing of bulk tumor specimens provides invaluable information, sequencing of individual cells provides a true representation of the cellular heterogeneity that exists within a cancer. Novel technologies such as single cell copy number variation (scCNV) enable copy number profiling at a single cell resolution. Single Cell CNV generates genome wide sequencing libraries from single cells to reveal tumor heterogeneity and evolution of subclonal populations. Methods: In this study, we utilized a scCNV assay to assess heterogeneity within the 4T1 murine breast tumor model. To accomplish this we have developed an end-to-end workflow including tissue dissociation, single cell library preparation, sequencing and data analysis. We injected 4T1 cells into the mammary fat pad of 4-6 week old BALB/c mice. Mice were sacrificed at 21 days and tumors were removed from the injection site and dissociated using Milteny’s Biotec Octo Dissociator. We utilized the 10X Genomics Chromium system to partition single cells and prepare sequencing libraries in parallel such that all DNA fragments produced within a partition are barcoded. Following library construction, the Illumina Novaseq 6000 system was used to sequence single cell libraries. Additionally, single cell libraries from a fraction of the 4T1 cells that were injected into the mammary fat and non-metastatic isogeneic cell line variants, 67NR and 168FARN, were also sequenced. Results: We observed a pair of amplifications (>8 copies) on chromosome 9 and three segments of amplification on chromosome 15 that were conserved throughout the injection site tumor cells. Interestingly, the amplifications on chromosome 15 encompass one of the most commonly observed breast cancer oncogenes, Myc, and the cell migration regulator, Skp2. Further, we observed three unique cluster of tumors cells which suggests the possibility of detecting major and minor clonal populations using this technology. Conclusion: Our findings suggest scCNV will help us to improve characterizations of the entirety of a patient’s disease to uncover potential clones that are primed to induce metastasis, drug resistance, and relapse. Citation Format: Lee D. Gibbs, Jing Qian, Michelle Webb, Sharon Chang, Zarko Manojlovic, Enrique I. Velazquez, Troy McEachron, David W. Craig, John D. Carpten. Single Cell CNV End to End workflow to uncover tumor heterogeneity in a murine breast cancer model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4703.

This paper analyses how much culture is valued in a newly-developed economy with a distinct dichotomy of an arts-appreciating population segment and a less-culturally aware mass. An analytical framework weaving together the intrinsic, business and societal benefits of arts and culture is applied to explore whether arts festivals – a popular tourism event in many countries – are a temporary fad, an expensive governmental fetish or a naturally-evolving fixture. This has implications for government funding and cultural policy. Empirical evidence supports the notion that the long-running performing arts festival is a not a fad but a fixture with some fetish elements while the visual arts festival appears to be a fad but has the potential to be a fixture. Of particular concern, however, is the evidence from both festivals that the perceptions of community benefit, business benefits as well as bequest value from the arts are not significant determinants of willingness to pay for these events.

A patient with newly diagnosed end-stage renal disease (ESRD) received a femoral catheter for hemodialysis (HD). Shortly thereafter he developed fever, and blood cultures grew methicillin-resistant Staphylococcus aureus. The catheter was removed and the patient was treated with both vancomycin and rifampin; however, blood culture positivity persisted. The cerebrospinal fluid showed sterile meningitis. Subsequent imaging studies demonstrated aortic valve endocarditis and multiple mycotic aneurysms that appeared to include the intra- and extracranial vessels. The patient eventually died from sepsis. This case illustrates the aggressive and invasive nature of systemic infection with S. aureus and underscores the high morbidity and mortality associated with infections related to HD catheters.

We present two cases of peritoneal dialysis (PD) catheter-related Pseudomonas peritonitis that were poorly responsive to treatment guidelines of antibiotics and early catheter removal, and uncommonly complicated with ongoing intractable infections. An emergency exploratory laparotomy with extensive intraoperative peritoneal lavage and drainage was performed. The patients recovered dramatically and were transferred to hemodialysis permanently. These unusual cases show the possibility of persistent intra-abdominal infection that may extend extra-abdominally. Early diagnosis of persistent infection, timely surgical intervention, and concept of source control are of utmost importance.

Human erythrocyte glycophorin C plays a functionally important role in maintaining erythrocyte shape and regulating membrane mechanical stability. Immunochemical and serologic studies have identified a number of glycophorin C variants that include the Yus, Gerbich, and Webb phenotypes. We report here the molecular characterization of these variants. Amplification of glycophorin C mRNA from the Yus phenotype, using two oligonucleotide primers that span the coding domain, generated a 338-bp fragment compared with a 395-bp fragment generated by amplification of normal glycophorin C mRNA. Sequencing of the mutant 338-bp fragment identified a 57-bp deletion that corresponds to exon 2 of the glycophorin C gene. Similar analysis showed deletion of 84-bp exon 3 in the Gerbich phenotype. In contrast to the generation of shorter than normal DNA fragments from mRNA amplification in the Yus and Gerbich phenotypes, amplification of mRNA from the Webb phenotype generated a normal-sized fragment. Sequencing of this DNA fragment showed an A----G substitution at nucleotide 23 of the coding sequence, resulting in the substitution of asparagine by serine. This modification accounts for the altered glycosylation of glycophorin C seen in this phenotype. These results have enabled us to characterize glycophorin C variants in three different phenotypes that involve deletions of exons 2 and 3 of the glycophorin C gene, as well as a point mutation in exon 1 that results in altered glycosylation of this protein.

A patient with newly diagnosed end-stage renal disease (ESRD) received a femoral catheter for hemodialysis (HD). Shortly thereafter he developed fever, and blood cultures grew methicillin-resistant Staphylococcus aureus. The catheter was removed and the patient was treated with both vancomycin and rifampin; however, blood culture positivity persisted. The cerebrospinal fluid showed sterile meningitis. Subsequent imaging studies demonstrated aortic valve endocarditis and multiple mycotic aneurysms that appeared to include the intra- and extracranial vessels. The patient eventually died from sepsis. This case illustrates the aggressive and invasive nature of systemic infection with S. aureus and underscores the high morbidity and mortality associated with infections related to HD catheters.

A patient with newly diagnosed end-stage renal disease (ESRD) received a femoral catheter for hemodialysis (HD). Shortly thereafter he developed fever, and blood cultures grew methicillin-resistant Staphylococcus aureus. The catheter was removed and the patient was treated with both vancomycin and rifampin; however, blood culture positivity persisted. The cerebrospinal fluid showed sterile meningitis. Subsequent imaging studies demonstrated aortic valve endocarditis and multiple mycotic aneurysms that appeared to include the intra- and extracranial vessels. The patient eventually died from sepsis. This case illustrates the aggressive and invasive nature of systemic infection with S. aureus and underscores the high morbidity and mortality associated with infections related to HD catheters.