Background and Aims:Primary sclerosing cholangitis (PSC) is an immune-mediated liver disease frequently associated with inflammatory bowel disease (IBD). PSC-IBD represents a distinct phenotype with extensive colitis, right-sided predominance, and elevated colorectal cancer risk. We aimed to evaluate the impact of oral vancomycin on clinical, endoscopic, and histologic findings of IBD and both intestinal and liver biomarkers of these patients. Methods:A retrospective study was performed among patients with PSC-IBD treated with oral vancomycin from January 1992 to August 2024. Data collected included demographics, disease characteristics, prior therapies, vancomycin use and dosing, clinical response, laboratory markers, endoscopic, and histologic activity of the colon. Vancomycin-free survival was estimated using Kaplan-Meier analysis. Results:Among 90 patients (80% ulcerative colitis) included, the median age at PSC diagnosis was 17.4 years. Clinical improvement related to intestinal inflammation was observed in 50%, and 12.2% achieved remission. Endoscopic inactivity increased from 18.8% to 60.3%, and histologic inactivity or mild disease rose from 57.7% to 86.2%. Median change in serum alkaline phosphatase was -48.5 U/L (P = .5681), and median fecal calprotectin decreased from 485 μg/g to 67.7 μg/g. Clinical, endoscopic, and biochemical improvements were observed across low- (≤500 mg/d) and high-dose (>500 mg/d) groups. Five-year vancomycin-free survival was comparable between dose groups. Conclusion:Oral vancomycin was associated with meaningful improvements in clinical, endoscopic, histologic, and biomarker outcomes in intestinal inflammation of patients with PSC-IBD, with durable responses across different doses. These findings support vancomycin as a potential disease-modifying therapy, warranting prospective randomized trials to establish efficacy, optimal dosing, and long-term safety.
The group of > 40 cryptic whitefly species called Bemisia tabaci sensu lato are amongst the world's worst agricultural pests and plant-virus vectors. Outbreaks of B. tabaci s.l. and the associated plant-virus diseases continue to contribute to global food insecurity and social instability, particularly in sub-Saharan Africa and Asia. Published B. tabaci s.l. genomes have limited use for studying African cassava B. tabaci SSA1 species, due to the high genetic divergences between them. Genomic annotations presented here were performed using the 'Ensembl gene annotation system', to ensure that comparative analyses and conclusions reflect biological differences, as opposed to arising from different methodologies underpinning transcript model identification.We present here six new B. tabaci s.l. genomes from Africa and Asia, and two re-annotated previously published genomes, to provide evolutionary insights into these globally distributed pests. Genome sizes ranged between 616-658 Mb and exhibited some of the highest coverage of transposable elements reported within Arthropoda. Many fewer total protein coding genes (PCG) were recovered compared to the previously published B. tabaci s.l. genomes and structural annotations generated via the uniform methodology strongly supported a repertoire of between 12.8-13.2 × 103 PCG. An integrative systematics approach incorporating phylogenomic analysis of nuclear and mitochondrial markers supported a monophyletic Aleyrodidae and the basal positioning of B. tabaci Uganda-1 to the sub-Saharan group of species. Reciprocal cross-mating data and the co-cladogenesis pattern of the primary obligate endosymbiont 'Candidatus Portiera aleyrodidarum' from 11 Bemisia genomes further supported the phylogenetic reconstruction to show that African cassava B. tabaci populations consist of just three biological species. We include comparative analyses of gene families related to detoxification, sugar metabolism, vector competency and evaluate the presence and function of horizontally transferred genes, essential for understanding the evolution and unique biology of constituent B. tabaci. s.l species.These genomic resources have provided new and critical insights into the genetics underlying B. tabaci s.l. biology. They also provide a rich foundation for post-genomic research, including the selection of candidate gene-targets for innovative whitefly and virus-control strategies.
New oncology therapies are driven by multiple approaches, with a heavy emphasis on small-molecule therapeutics to target cancer cells and provide a therapeutic benefit to cancer patients. These small-molecule compounds can be used as a stand-alone treatment approach or may be combined with other compounds to bring enhanced effects. Compound therapeutic discovery relies heavily on high-throughput screening assays for measurement of phenotypic responses following compound treatment of oncology cell cultures which can range from very targeted assays to wide-ranging unbiased approaches. Standard whole transcriptome RNA-seq is a preferred method for unbiased measurement of phenotypic responses but is often overlooked due to limited scalability and high sample screening costs. To address these challenges, we have developed a high-throughput gene expression (HT-GEx) assay that combines a variety of strategies to enable a low-cost and high-throughput alternative to standard RNA-seq. First, a simplified workflow removes upstream RNA isolation steps and tags transcripts directly from cell lysate. This is achieved by incorporating both a sample barcode and a unique molecular index (UMI) during the reverse transcription reaction. Next, we leverage a 3’ end counting approach to enable a reduction in sequencing depth coverage (i.e. sample cost) without compromising gene detection sensitivity. With these key advances, a high-plex and high-throughput screening assay is achievable at a reduced cost by removing the need to purify RNA, tagging transcripts early in the workflow to allow pooling of samples and reducing sequencing depth. We have combined these high-throughput and cost-saving strategies and present results which confirm HT-GEx offers results on par with standard RNA-seq. Gene detection sensitivity based on number of genes detected per millions of reads is highly similar, with gene detection sensitivity saturated at approximately 2 million reads. Additionally, the number of genes detected between replicates for RNA samples and lysate samples demonstrate strong linear correlation, implying highly reproducible results. Thus, high-throughput gene expression is an ideal method for phenotypic screening in oncology cell lines following stand-alone or combined compound treatments. Citation Format: Andrea O'Hara, Michael Stephens, Ilaria DeVito, Laure Turner, Christopher Mozdzierz, Haythem Latif, Ginger Zhou. High-throughput RNA sequencing directly from cell lysates enables reproducible phenotypic profiling for assessing novel compounds and treatments in cancer research [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB130.
Some of the protist species which colonize the hindguts of wood-feeding Reticulitermes termites are associated with endosymbiotic bacteria belonging to the genus Endomicrobium. In this study, we focused on the endosymbionts of three protist species from Reticulitermes flavipes, as follows: Pyrsonympha vertens, Trichonympha agilis, and Dinenympha species II. Since these protist hosts represented members of different taxa which colonize separate niches within the hindguts of their termite hosts, we investigated if these differences translated to differential gene content and expression in their endosymbionts. Following assembly and comparative genome and transcriptome analyses, we discovered that these endosymbionts differed with respect to some possible niche-specific traits, such as carbon metabolism. Our analyses suggest that species-specific genes related to carbon metabolism were acquired by horizontal gene transfer (HGT) and may have come from taxa which are common in the termite hind gut. In addition, our analyses suggested that these endosymbionts contain and express genes related to natural transformation (competence) and recombination. Taken together, the presence of genes acquired by HGT and a putative competence pathway suggest that these endosymbionts are not cut off from gene flow and that competence may be a mechanism by which members of Endomicrobium can acquire new traits. IMPORTANCE The composition and structure of wood, which contains cellulose, hemicellulose, and lignin, prevent most organisms from using this common food source. Termites are a rare exception among animals, and they rely on a complex microbiota housed in their hindguts to use wood as a source of food. The lower termite, Reticulitermes flavipes, houses a variety of protists and prokaryotes that are the key players in the disassembly of lignocellulose. Here, we describe the genomes and the gene expression profiles of five Endomicrobium endosymbionts living inside three different protist species from R. flavipes. Data from these genomes suggest that these Endomicrobium species have different mechanisms for using carbon. In addition, they harbor genes that may be used to import DNA from their environment. This process of DNA uptake may contribute to the high levels of horizontal gene transfer noted previously in Endomicrobium species.
Bulk RNA sequencing (RNA-seq) is regularly employed for transcriptional profiling but provides only a snapshot of the average population. Particularly when studying disease, understanding differences in diverse cells is essential thus single-cell resolution is a necessity due to significant cellular heterogeneity. High-throughput droplet- and microfluidic-based approaches for performing single-cell RNA-seq (scRNA-seq) are invaluable techniques for uncovering changes in cells such as differential gene expression and epigenetic states in cancer research. A challenge for scRNA-seq, however, is sample preparation as typically tissues must be processed immediately after collection. We and others have reported alternative approaches to stabilize samples prior to analysis such as cryopreservation of cells and tissues and methanol-based fixation of cells. However, the inclusion of these approaches is still limited in many settings due to the challenging logistics involved in sample collection. To further broaden the ability of researchers to deploy scRNA-seq, we report our experiences from testing a pre-commercial workflow developed by 10x Genomics to resolve these sample management limitations. The use of paraformaldehyde (PFA) to fix samples at the collection site allows samples to be transported to remote laboratories for downstream processing without sacrificing integrity or data quality. This advance has enabled new possibilities for sample accessibility, throughput, and batched analysis in basic and translational research settings. Furthermore, this approach also allows for analysis of transcriptome-wide gene expression at high sensitivity with simultaneous cellular readouts. Here we report a case study comparing the PFA method to standard approaches, and highlight advantages and potential applications previously not possible with reported sample preparation strategies. Citation Format: David Corney, Yang Han, Yu Qiu, Yongjun Fan, Michael Stephens, Andrea O'Hara, Laure Turner, Christopher Mozdzierz, Haythem Latif, Ginger Zhou. Evaluation of a novel single-cell RNA sequencing methodology for use in clinical trial settings [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB034.
Background: Research on the utilization and effectiveness of antitumor necrosis factor (TNF) biologics in children with very early onset inflammatory bowel disease (VEOIBD) is urgently needed. Here we describe anti-TNF use and durability in a multicenter cohort. Methods: We performed a retrospective cohort study of patients diagnosed with VEOIBD (<6 years) between 2008 and 2013 at 25 North American centers. We performed chart abstraction at diagnosis and 1, 3, and 5 years after diagnosis. We examined the rate of initiation and durability of infliximab and adalimumab and evaluated associations between treatment durability and the following covariates with multivariate Cox proportional hazard regression: age at diagnosis, sex, disease duration, disease classification, and presence of combined immunomodulatory treatment versus monotherapy. Results: Of 294 children with VEOIBD, 120 initiated treatment with anti-TNF therapy and 101 had follow-up data recorded [50% Crohn disease (CD), 31% ulcerative colitis (UC), and 19% IBD unclassified (IBD-U)]. The cumulative probability of anti-TNF treatment was 15% at 1 year, 30% at 3 years, and 45% at 5 years from diagnosis; 56 (55%) were treated between 0 and 6 years old. Anti-TNF durability was 90% at 1 year, 75% at 3 years, and 55% at 5 years. The most common reason for discontinuation of anti-TNF were loss of response in 24 (57%) children. Children with UC/IBD-U had lower durability than those with CD (hazard ratio [HR] 0.17; 95% confidence interval [CI], 0.06–0.51; P = 0.001). Conclusions: Utilization and durability of anti-TNF in VEOIBD is relatively high and comparable with older children. Having Crohn disease (compared with UC/IBD-U) is associated with greater durability.
BACKGROUND AND AIMS Ileal strictures are the major indication for resective surgery in Crohn's disease (CD). We aimed to define ileal gene programs present at diagnosis linked with future stricturing behavior during five year follow-up, and to identify potential small molecules to reverse these gene signatures. METHODS Antimicrobial serologies and pre-treatment ileal gene expression were assessed in a representative subset of 249 CD patients within the RISK multicenter pediatric CD inception cohort study, including 113 that are unique to this report. These data were used to define genes associated with stricturing behavior and for model testing to predict stricturing behavior. A bioinformatics approach to define small molecules which may reverse the stricturing gene signature was applied. RESULTS 19 of the 249 patients developed isolated B2 stricturing behavior during follow-up, while 218 remained B1 inflammatory. Using deeper RNA sequencing than in our prior report, we have now defined an inflammatory gene signature including an oncostatin M co-expression signature, tightly associated with extra-cellular matrix (ECM) gene expression in those who developed stricturing complications. We further computationally prioritize small molecules targeting macrophage and fibroblast activation and angiogenesis which may reverse the stricturing gene signature. A model containing ASCA and CBir1 serologies and a refined eight ECM gene set was significantly associated with stricturing development by year five after diagnosis (AUC (95th CI) = 0.82 (0.7-0.94)). CONCLUSION An ileal gene program for macrophage and fibroblast activation is linked to stricturing complications in treatment naïve pediatric CD, and may inform novel small molecule therapeutic approaches.
Objective Orthostatic intolerance (OI) and autonomic dysfunction (AD) are common in adolescents and young adults. Patients experience multisystem symptoms including gastrointestinal (GI), postural orthostatic tachycardia syndrome (POTS), orthostatic hypotension (OH), or only symptoms of OI (SOI) without significant findings on 70-degree head-up tilt testing (HUT). We hypothesize that patients with POTS, OH, and SOI show differences in GI symptoms and motility test and that heart rate (HR) changes on HUT predict severity of GI dysmotility. Study design From medical records of patients (<18 years) with OI, we collected demographics, presenting symptoms, GI manifestations, and GI motility testing. Data were compared between the 3 groups (POTS, OH, and SOI). We assessed changes in HR on HUT with changes on GI motility evaluation. Results Two hundred twenty-nine patients were included (73% females). Abdominal pain (65%), nausea (49%), vomiting (18%), and constipation (24%) were the most common GI symptoms. In patients who had motility evaluation, there were 27% (53/193) with delayed gastric emptying (GE) at 4 hours, 35% (32/92) with delayed colonic transit (CT), 55% (17/31) with reduced gastric accommodation (GA), and 75% (21/28) with dyssynergic defecation (DD). Among 100 POTS, 34 OH, and 95 SOI patients, no significant differences in GI symptoms or motility tests were identified and HR changes on HUT were not associated with changes on motility tests. Conclusion GI symptoms are frequent in adolescents with OI and are associated with delayed GE, reduced GA, delayed CT, and presence of DD.
BACKGROUND The incidence of very early onset inflammatory bowel disease (VEOIBD) is increasing, yet the phenotype and natural history of VEOIBD are not well described. METHODS We performed a retrospective cohort study of patients diagnosed with VEOIBD (6 years of age and younger) between 2008 and 2013 at 25 North American centers. Eligible patients at each center were randomly selected for chart review. We abstracted data at diagnosis and at 1, 3, and 5 years after diagnosis. We compared the clinical features and outcomes with VEOIBD diagnosed younger than 3 years of age with children diagnosed with VEOIBD at age 3 to 6 years. RESULTS The study population included 269 children (105 [39%] Crohn's disease, 106 [39%] ulcerative colitis, and 58 [22%] IBD unclassified). The median age of diagnosis was 4.2 years (interquartile range 2.9-5.2). Most (94%) Crohn's disease patients had inflammatory disease behavior (B1). Isolated colitis (L2) was the most common disease location (70% of children diagnosed younger than 3 years vs 43% of children diagnosed 3 years and older; P = 0.10). By the end of follow-up, stricturing/penetrating occurred in 7 (6.6%) children. The risk of any bowel surgery in Crohn's disease was 3% by 1 year, 12% by 3 years, and 15% by 5 years and did not differ by age at diagnosis. Most ulcerative colitis patients had pancolitis (57% of children diagnosed younger than 3 years vs 45% of children diagnosed 3 years and older; P = 0.18). The risk of colectomy in ulcerative colitis/IBD unclassified was 0% by 1 year, 3% by 3 years, and 14% by 5 years and did not differ by age of diagnosis. CONCLUSIONS Very early onset inflammatory bowel disease has a distinct phenotype with predominantly colonic involvement and infrequent stricturing/penetrating disease. The cumulative risk of bowel surgery in children with VEOIBD was approximately 14%-15% by 5 years. These data can be used to provide anticipatory guidance in this emerging patient population.
The hindgut protists of wood-feeding termites are usually colonized by prokaryotic symbionts. Many of the hurdles that have prevented a better understanding of these symbionts arise from variation among protist and termite host species and the inability to maintain prominent community members in culture. These issues have made it difficult to study the fidelity, acquisition, and differences in colonization of protists by bacterial symbionts. In this study, we use high throughput amplicon sequencing of the V4 region of 16S rRNA genes to determine the composition of bacterial communities associated with single protist cells of six protist species, from the genera Pyrsonympha, Dinenympha, and Trichonympha that are present in the hindgut of the termite Reticulitermes flavipes. By analyzing amplicon sequence variants (ASVs), the diversity and distribution of protist-associated bacteria was compared within and across these six different protist species. ASV analysis showed that, in general, each protist genus associated with a distinct community of bacterial symbionts which were conserved across different termite colonies. However, some ASVs corresponding to ectosymbionts (Spirochaetes) were shared between different Dinenympha species and to a lesser extent with Pyrsonympha and Trichonympha hosts. This suggested that certain bacterial symbionts may be cosmopolitan to some degree and perhaps acquired by horizontal transmission. Using a fluorescence-based cell assay, we could observe the horizontal acquisition of surface-bound bacteria. This acquisition was shown to be timedependent, involve active processes, and was non-random with respect to binding locations on some protists.
Verruciform xanthoma (VX) is a rare finding thought to be caused by epidermal damage from trauma or inflammation and has been reported in a limited number of patients with recessive dystrophic epidermolysis bullosa (RDEB). Herein, we describe a 20-year-old woman with RDEB who developed a large, verrucous, pink plaque on the posterior thigh that was histologically proven to be a VX. We review cases of VX in patients with RDEB and summarize the clinical features, pathophysiology, and management principles.
Transverse melanonychia is a rare finding often secondary to chemotherapy, orally ingested medications, or other iatrogenic interventions. A 19-month-old boy with hemophagocytic lymphohistiocytosis treated with biweekly etoposide and dexamethasone developed transverse bands of pigment in all toenail and fingernail units consistent with transverse melanonychia. We review the literature for reported cases of transverse melanonychia and summarize suspected etiologies.
Background and Aims: Familial adenomatous polyposis (FAP) is a hereditary syndrome that can affect the entire GI tract. Current screening recommendations include EGD starting at age 25 to 30 years or earlier in symptomatic patients. However, few reports describe upper GI tract involvement in children with FAP that support the notion of early screening. The aim of our study is to understand the prevalence and severity of upper GI involvement in children with FAP. Methods: We performed a retrospective review of the Mayo Clinic records, between 1992 and 2016, to identify children with the diagnosis of FAP who underwent EGD examinations. A systematic review of the literature was performed to include published studies reporting children with FAP and upper GI findings. Results: The retrospective study included 69 children with a mean age of 13.5 years (range, 3-18). Thirty-six children (52%) had duodenal adenoma with low-grade dysplasia. Five children required an ampullectomy secondary to enlarged and polypoid ampullas. Combined with published studies, a total of 206 children with upper GI findings were identified, of which 87 (42%) had duodenal adenoma (1 had high-grade dysplasia). Meta-analysis of 5 series demonstrated duodenal adenoma detection rate of 39% (95% confidence interval, 21%-57%; I-2 = 85%). Conclusions: The available data to date show that children with FAP can have clinically relevant lesions in the upper GI tract earlier than previously foreseen, suggesting that earlier screening may be indicated. Larger multi-center prospective studies are needed to determine the best approach and optimal age for EGD screening in children with FAP.