ABSTRACT
We describe a phenotypic antibiotic susceptibility testing (AST) method that can provide an eightfold speed-up in turnaround time compared with the current clinical standard by leveraging advances in microscopy and single-cell imaging. A newly developed growth plate containing 96 agarose pads, termed the multipad agarose plate (MAP), can be assembled at low cost. Pads can be prepared with dilution series of antibiotics. Bacteria are seeded on the pads and automatically imaged using brightfield microscopy, with a fully automated segmentation pipeline quantifying microcolony formation and growth rate. Using a test set of nine antibiotics with very different targets, we demonstrate that accurate minimum inhibitory concentration (MIC) measurements can be performed based on the growth rate of microcolonies within 3 h of incubation with the antibiotic when started from exponential phase. Faster, reliable and high-throughput methods for AST, such as MAP, could improve patient care by expediting treatment initiation and alleviating the burden of antimicrobial resistance.
Subject(s)
Anti-Bacterial Agents , Bacteria , Humans , Sepharose , Anti-Bacterial Agents/pharmacology , Microbial Sensitivity Tests , MicroscopyABSTRACT
The channel catfish (Ictalurus punctatus) farming industry is the largest and one of the oldest aquaculture industries in the United States. Despite being an established industry, production issues stemming from disease outbreaks remain problematic for producers. Supplementing fish diets with probiotics to enhance the immune system and growth potential is one approach to mitigating disease. Although considerable laboratory data demonstrate efficacy, these results do not always translate to natural modes of disease transmission. Hence, the present work was conducted in the laboratory but incorporated flow-through water from large catfish pond production systems, allowing for natural exposure to pathogens. Two feeding trials were conducted in an 18-tank aquaria system housing two different sizes, 34.8 ± 12.5 g and 0.36 ± 0.03 g, of channel catfish. Channel catfish in the first trial were fed three experimental diets over six weeks. Commercial diets were top-coated with two selected spore-forming Bacillus spp. probiotics, Bacillus velezensis AP193 (1 × 106 CFU g−1) and BiOWiSH (3.6 × 104 CFU g−1), or a basal diet that contained no dietary additive. In the second eight-week trial, diets were top-coated with BiOWiSH at three concentrations (1.8, 3.6, and 7.3 × 104 CFU g−1), along with one basal diet (no probiotic). At the completion of these studies, growth performance, survival, hematocrit, blood chemistry, and immune expression of interleukin 1ß (il1ß), tumor necrosis factor-alpha (tnf-α), interleukin-8 (il8), transforming-growth factor ß1 (tgf-ß1), and toll-like receptor 9 (tlr9) were evaluated using qPCR. Trial results revealed no differences (p > 0.05) among treatments concerning growth, survival, or hematological parameters. For immune gene expression, interesting trends were discerned, with substantial downregulation observed in B. velezensis AP193-fed fish for il1ß, tnf-α, and tlr9 expression within splenic tissue, compared to that of the basal and BiOWiSH diets (p < 0.05). However, the results were not statistically significant for anterior kidney tissue in the first trial. In the second trial, varied levels of probiotic inclusion revealed no significant impact of BiOWiSH's products on the expression of il1ß, tnf-α, il8, and tgf-ß1 in both spleen and kidney tissue at any rate of probiotic inclusion (p > 0.05). Based on these findings, more research on utilizing probiotics in flow-through systems with natural infection conditions is crucial to ensure consistency from a controlled laboratory scale to real-world practices.
ABSTRACT
INTRODUCTION: Henoch-Schönlein purpura is a common immunoglobulin A-mediated vasculitic syndrome in children, characterized by purpuric rash, arthritis and abdominal pain. Renal involvement, manifested by the presence of hematuria and/or proteinuria, is also frequently seen. In most cases, patients with this disease achieve complete recovery, but some progress to renal impairment. Gastro-intestinal manifestations are present in two-thirds of affected patients and range from vomiting, diarrhea, and peri-umbilical pain to serious complications such as intussusception and gastrointestinal hemorrhage. CASE PRESENTATION: We report the case of a 7-year-old Caucasian girl who presented with abdominal pain, labial swelling, and a large abdominal ecchymosis two weeks after having been diagnosed with Henoch-Schönlein purpura. A computed tomography scan revealed abdominal wall edema extending to the groin, without any intra-abdominal pathology. She was successfully treated with intravenous steroids. CONCLUSION: Circumferential anterior abdominal wall edema and labial edema have never been reported previously, to the best of our knowledge, as a complication of Henoch-Schönlein purpura. These findings further contribute to the wide spectrum of manifestations of this disorder in the literature, aiding in its recognition and management.
