Partial RAG deficiency in humans induces dysregulated peripheral lymphocyte development and humoral tolerance defect with accumulation of T-bet+ B cells.

The recombination-activating genes (RAG) 1 and 2 are indispensable for diversifying the primary B cell receptor repertoire and pruning self-reactive clones via receptor editing in the bone marrow; however, the impact of RAG1/RAG2 on peripheral tolerance is unknown. Partial RAG deficiency (pRD) manifesting with late-onset immune dysregulation represents an 'experiment of nature' to explore this conundrum. By studying B cell development and subset-specific repertoires in pRD, we demonstrate that reduced RAG activity impinges on peripheral tolerance through the generation of a restricted primary B cell repertoire, persistent antigenic stimulation and an inflammatory milieu with elevated B cell-activating factor. This unique environment gradually provokes profound B cell dysregulation with widespread activation, remarkable extrafollicular maturation and persistence, expansion and somatic diversification of self-reactive clones. Through the model of pRD, we reveal a RAG-dependent 'domino effect' that impacts stringency of tolerance and B cell fate in the periphery.

Exposure to environmentally relevant concentrations of ambient fine particulate matter (PM2.5) depletes the ovarian follicle reserve and causes sex-dependent cardiovascular changes in apolipoprotein E null mice.

BACKGROUND: Fine particulate matter (PM2.5) exposure accelerates atherosclerosis and contains known ovotoxic chemicals. However, effects of exposure to PM2.5 on the finite ovarian follicle pool have hardly been investigated, nor have interactions between ovarian and cardiovascular effects. We hypothesized that subchronic inhalation exposure to human-relevant concentrations of PM2.5 results in destruction of ovarian follicles via apoptosis induction, as well as accelerated recruitment of primordial follicles into the growing pool. Further, we hypothesized that destruction of ovarian follicles enhances the adverse cardiovascular effects of PM2.5 in females. RESULTS: Hyperlipidemic apolipoprotein E (Apoe) null ovary-intact or ovariectomized female mice and testis-intact male mice were exposed to concentrated ambient PM2.5 or filtered air for 12 weeks, 5 days/week for 4 h/day using a versatile aerosol concentration enrichment system. Primordial, primary, and secondary ovarian follicle numbers were decreased by 45%, 40%, and 17%, respectively, in PM2.5-exposed ovary-intact mice compared to controls (P < 0.05). The percentage of primary follicles with granulosa cells positive for the mitosis marker Ki67 was increased in the ovaries from PM2.5-exposed females versus controls (P < 0.05), consistent with increased recruitment of primordial follicles into the growing pool. Exposure to PM2.5 increased the percentages of primary and secondary follicles with DNA damage, assessed by γH2AX immunostaining (P < 0.05). Exposure to PM2.5 increased the percentages of apoptotic antral follicles, determined by TUNEL and activated caspase 3 immunostaining (P < 0.05). Removal of the ovaries and PM2.5-exposure exacerbated the atherosclerotic effects of hyperlipidemia in females (P < 0.05). While there were statistically significant changes in blood pressure and heart rate variability in PM2.5-compared to Air-exposed gonad-intact males and females and ovariectomized females, the changes were not consistent between exposure years and assessment methods. CONCLUSIONS: These results demonstrate that subchronic PM2.5 exposure depletes the ovarian reserve by increasing recruitment of primordial follicles into the growing pool and increasing apoptosis of growing follicles. Further, PM2.5 exposure and removal of the ovaries each increase atherosclerosis progression in Apoe-/- females. Premature loss of ovarian function is associated with increased risk of osteoporosis, cardiovascular disease and Alzheimer's disease in women. Our results thus support possible links between PM2.5 exposure and other adverse health outcomes in women.

Magnetic control of graphitic microparticles in aqueous solutions.

Graphite is an inexpensive material with useful electrical, magnetic, thermal, and optical properties. It is also biocompatible and used universally as a substrate. Micrometer-sized graphitic particles in solution are therefore ideal candidates for novel lab-on-a-chip and remote manipulation applications in biomedicine, biophysics, chemistry, and condensed-matter physics. However, submerged graphite is not known to be amenable to magnetic manipulation, the optimal manipulation method for such applications. Here, we exploit the diamagnetism of graphite and demonstrate contactless magnetic positioning control of graphitic microflakes in diamagnetic aqueous solutions. We develop a theoretical model for magnetic manipulation of graphite microflakes and demonstrate experimentally magnetic transport of such particles over distances [Formula: see text] with peak velocities [Formula: see text] in inhomogeneous magnetic fields. We achieve fully biocompatible transport for lipid-coated graphite in NaCl aqueous solution, paving the way for previously undiscovered biomedical applications. Our results prove that micrometer-sized graphite can be magnetically manipulated in liquid media.

Rare Case Report of Pilomatrical Carcinosarcoma in a Pediatric Patient.

We present a case report of the exceptionally rare pilomatrical carcinosarcoma in an even rarer pediatric age group, a 9-year-old female patient. The tumor showed biphasic pilomatrical carcinoma and malignant sarcomatous transformation. To date, the patient is healing well without signs of recurrence. Although limited clinical follow-up is available due to the recent diagnosis, this case may provide a rare look at the clinical outcome of this very rare tumor.

Effects of aging and environmental tobacco smoke exposure on ocular and plasma circulatory microRNAs in the Rhesus macaque.

Purpose: To identify changes induced by environmental tobacco smoke (ETS) in circulatory microRNA (miRNA) in plasma and ocular fluids of the Rhesus macaque and compare these changes to normal age-related changes. Tobacco smoke has been identified as the leading environmental risk factor for age-related macular degeneration (AMD). Methods: All Rhesus macaques were housed at the California National Primate Research Center (CNPRC), University of California, Davis. Four groups of animals were used: Group 1 (1-3 years old), Group 2 (19-28 years old), Group 3 (10-16 years old), and Group 4 (middle aged, 9-14 years old). Group 4 was exposed to smoke for 1 month. Ocular fluids and plasma samples were collected, miRNAs isolated, and expression data obtained using Affymetrix miRNA GeneTitan Array Plates 4.0. Bioinformatics analysis was done on the Affymetrix Expression Console (EC), Transcriptome Analysis Software (TAS) using ANOVA for candidate miRNA selection, followed by Ingenuity Pathway Analysis (IPA). Results: The expression of circulatory miRNAs showed statistically significant changes with age and ETS. In the plasma samples, 45 miRNAs were strongly upregulated (fold change >±1.5, p<0.05) upon ETS exposure. In the vitreous, three miRNAs were statistically significantly downregulated with ETS, and two of them (miR-6794 and miR-6790) were also statistically significantly downregulated with age. Some retinal layers exhibited a thinning trend measured with optical coherence tomography (OCT) imaging. The pathways activated were IL-17A, VEGF, and recruitment of eosinophils, Th2 lymphocytes, and macrophages. Conclusions: ETS exposure of Rhesus macaques resulted in statistically significant changes in the expression of the circulatory miRNAs, distinct from those affected by aging. The pathways activated appear to be common for ETS and AMD pathogenesis. These data will be used to develop an animal model of early dry AMD.

The Role of Medicinal Cannabis as an Emerging Therapy for Opioid Use Disorder.

This narrative review explores current insights into the potential use of medicinal cannabis-related products as an emerging therapy for opioid use disorder in the landscape of increasing knowledge about medicinal cannabis-based products, commercialisation and global legalisation. Preclinical studies have provided preliminary insight into the putative neurobiological mechanisms that underpin the potential for medicinal cannabis to be considered a therapeutic in opioid use disorder and addiction. With the progressive legalisation of cannabis in many jurisdictions worldwide, contemporary research has highlighted further evidence that medicinal cannabis may have efficacy in reducing cravings and withdrawal effects, and therefore may be considered as an adjunct or standalone to current medications for opioid use disorder. Despite this potential, the landscape of research in this space draws from a large number of observational studies, with a paucity of rigorous randomised controlled trials to ascertain a true understanding of effect size and safety profile. With current challenges in implementation that arise from political and legal qualms about adopting medicinal cannabis on the background of associated social stigma, significant hurdles remain to be addressed by government, policy-makers, healthcare providers and researchers before medical cannabis can be introduced globally for the treatment of opioid use disorder.

The aim of this review was to synthesise current evidence to understand how medicinal cannabis products may be able to tackle the signs, symptoms and outcomes related to opioid dependence. At the present time, opioid dependence is associated with a significant burden of disease and death in the community. Current treatment for opioid dependence includes supplying controlled-release opioids in a regulated (and often observed) manner in the community. However, despite the implementation of this strategy, the outcomes related to opioid use and dependence remain relatively unchanged, indicating that the current gold standard treatment is not as effective as it should be. Following the legalisation and commercialisation of medicinal cannabis, there has been increased research into the ways these products can be leveraged for different conditions and indications, including in opioid dependence. Given this context, in this narrative we explore this preliminary evidence and evaluate the steps required in further research and policy changes before more widespread implementation of medical cannabis can be considered.

Primary Hodgkin lymphoma of the central nervous system: two case reports and review of the literature.

CNS involvement by systemic Hodgkin lymphoma (HL) is quite rare, but the disease limited to the CNS is an exceptionally rare entity. The incidence of CNS-HL has been estimated at 0.2-0.5% of cases, but a more recent study has modified that figure to less than 0.02%. Like the conventional form, the diagnosis of primary CNS-HL rests upon distinct morphological and immunohistochemical characteristics, including diagnostic Reed-Sternberg cells, in addition to staging studies demonstrating a lack of disease elsewhere. The paucity of cases in the literature precludes reliable clinical and demographic data, as well as a consensus on treatment and prognosis. We present two cases of primary cerebellar HL, one with 10-year follow-up, and a relevant review of the literature.

Determining weathering-induced heterogeneous oxidation profiles of polyethylene, polypropylene and polystyrene using laser-induced breakdown spectroscopy.

Weathering-induced polymer degradation is typically heterogeneous which plays an integral part in fragmentation. Despite that, the current selection of techniques to investigate such heterogeneities, especially beneath the sample surface, is sparse. We introduce Laser-induced Breakdown Spectroscopy (LIBS) as an analytical tool and evaluate its performance for depth profiling. Three types of polymers were selected (polyethylene, polypropylene, and polystyrene) that were aged under controlled conditions. We demonstrate that LIBS can detect heterogeneous oxidation on the surface and inside the samples. The results reveal that different oxidation behaviors are linked to the sample's lattice structure and the subsequent formation of microcracks. This implies that LIBS is beneficial to give additional insights into the weathering and degradation behavior of environmentally relevant plastics.

Peeling Back the Layers: Sloughing Esophagitis in a Teenager with Chronic Vomiting.

Esophagitis dissecans superficialis (EsoDS) is a rare condition characterized by the shedding of superficial esophageal epithelium. Limited data exists on EsoDS in the pediatric population. We present a case of a 17-year-old female with chronic nausea and vomiting diagnosed with EsoDS. Endoscopy revealed esophageal mucosal sloughing, and histology confirmed esophagitis with mucosal necrosis. EsoDS is underrecognized, and its association with psychoactive medications remains unclear. Fortunately, EsoDS cases tend to resolve spontaneously without complications. Awareness of EsoDS is essential, and further research is needed to understand its prevalence and outcomes in pediatric patients.

Esophageal Heterotopic Pancreas in an Asymptomatic 2-Year-Old With VACTERL Association.

A 2-year-old male with VACTERL association and asthma presented to the emergency room due to asthma exacerbation. Chest radiography revealed lingular pneumonia and thickening of the left paraspinal line of the gastroesophageal junction. Chest computed tomography confirmed a heterogeneous fluid- and gas-filled structure at the left posterior lateral posterolateral aspect of the esophagus, which was suspected to be an esophageal diverticulum on an upper gastrointestinal series. The esophageal diverticulum was excised via left thoracoscopy, and pathological examination revealed pancreatic tissue. Heterotopic pancreas lacks anatomical, vascular, or ductal continuity with the native pancreas. It is usually asymptomatic, but when discovered, it usually occurs later in life. It has been described in the foregut, but is not as common in the esophagus, especially in the pediatric population. This case report highlights the rare occurrence, and importance of considering, esophageal heterotopic pancreas within an esophageal diverticulum in an asymptomatic patient with VACTERL association.

Heterotopic Gastric Mucosa Causing Rectal Bleeding in a Young Child.

Heterotopic gastric mucosa (HGM) in the colon and small bowel is a very rare finding. We report a case of HGM in the rectum of an 8-year-old child with a history of eosinophilic esophagitis after having a colonoscopy to evaluate for inflammatory bowel disease. The colonoscopy was normal except for rectal tissue erythema and edema. Inflammatory bowel disease has been reported in some cases of children with eosinophilic changes of the esophagus. The child had intermittent rectal bleeding thought to be due to constipation. Interestingly, when the patient was placed on a proton pump inhibitor for the treatment of eosinophilic esophagitis, the rectal bleeding decreased. After our patient ceased proton pump inhibitor therapy, he experienced a large amount of rectal bleeding. Histological findings revealed HGM in the colon/rectum. An extensive review of the incidence, diagnosis, and treatment is discussed.

Identifying plastics with photoluminescence spectroscopy and machine learning.

A quantitative understanding of the worldwide plastics distribution is required not only to assess the extent and possible impact of plastic litter on the environment but also to identify possible counter measures. A systematic collection of data characterizing amount and composition of plastics has to be based on two crucial components: (i) An experimental approach that is simple enough to be accessible worldwide and sensible enough to capture the diversity of plastics; (ii) An analysis pipeline that is able to extract the relevant parameters from the vast amount of experimental data. In this study, we demonstrate that such an approach could be realized by a combination of photoluminescence spectroscopy and a machine learning-based theoretical analysis. We show that appropriate combinations of classifiers with dimensional reduction algorithms are able to identify specific material properties from the spectroscopic data. The best combination is based on an unsupervised learning technique making our approach robust to alternations of the input data.

The Evolution of Very Early Onset Inflammatory Bowel Disease, Autoimmune Hepatitis, and Primary Sclerosing Cholangitis in a Young Girl.

Very early onset inflammatory bowel disease, autoimmune hepatitis (AIH), or primary sclerosing cholangitis (PSC) alone is a rare condition in young children. The combination of all 3 autoimmune disorders in a 16-month-old child is even rarer. The onset and etiology of these diseases is multifactorial and typically unknown. However, when the children are diagnosed, the accepted view point is that the inflammation was likely present for months to years prior. This case is unique because the gastrointestinal problems started from infancy, and evolved to the development of Crohn's disease, AIH, and PSC at a very early age. This case helps bring to light that very early onset autoimmune disorders may in fact present with symptoms of feeding difficulties, growth failure, and formula intolerance. Patients may be diagnosed initially with allergic enterocolitis in infancy. Although few children with these symptoms evolve to develop autoimmune diseases at an older age, clinicians should consider following these children more closely. This case also demonstrates how hard it is to diagnose very early onset autoimmune disorders, as they mimic other illnesses.

Troglitazone suppresses telomerase activity independently of PPARgamma in estrogen-receptor negative breast cancer cells.

BACKGROUND: Breast cancer is one the highest causes of female cancer death worldwide. Many standard chemotherapeutic agents currently used to treat breast cancer are relatively non-specific and act on all rapidly dividing cells. In recent years, more specific targeted therapies have been introduced. It is known that telomerase is active in over 90% of breast cancer tumors but inactive in adjacent normal tissues. The prevalence of active telomerase in breast cancer patients makes telomerase an attractive therapeutic target. Recent evidence suggests that telomerase activity can be suppressed by peroxisome proliferator activated receptor gamma (PPARgamma). However, its effect on telomerase regulation in breast cancer has not been investigated. METHODS: In this study, we investigated the effect of the PPARgamma ligand, troglitazone, on telomerase activity in the MDA-MB-231 breast cancer cell line. Real time RT-PCR and telomerase activity assays were used to evaluate the effect of troglitazone. MDA-MB-231 cells had PPARgamma expression silenced using shRNA interference. RESULTS: We demonstrated that troglitazone reduced the mRNA expression of hTERT and telomerase activity in the MDA-MB-231 breast cancer cell line. Troglitazone reduced telomerase activity even in the absence of PPARgamma. In agreement with this result, we found no correlation between PPARgamma and hTERT mRNA transcript levels in breast cancer patients. Statistical significance was determined using Pearson correlation and the paired Student's t test. CONCLUSIONS: To our knowledge, this is the first time that the effect of troglitazone on telomerase activity in breast cancer cells has been investigated. Our data suggest that troglitazone may be used as an anti-telomerase agent; however, the mechanism underlying this inhibitory effect remains to be determined.

Gastric Xanthoma in the Pediatric Population: A Possible Herald for Malignancy?

Gastric xanthoma is frequently an incidental finding on upper endoscopy in adults. Gastric xanthomas (GX) can be mistaken for malignancies and warrant prompt histologic diagnosis. The underlying etiology is not fully understood; however, it has been linked to Helicobacter pylori gastritis and gastric cancer. GX in the pediatric population is largely unreported in the literature. Because of the relative rarity, documentation with case reports are essential to provide as much data as possible to see if there is a correlation between GX and malignant potential in the pediatric population. Our group is reporting two cases, a 10-year-old male and a 7-year-old male, both who presented with chronic dysphagia, upper abdominal pain, nausea, vomiting, and loss of appetite. Upper endoscopies for both patients revealed small polypoid lesions located in the antrum with foamy histiocytes on histology, leading to the diagnosis of gastric xanthoma.

Quantification of atrazine and its metabolites in urine by on-line solid-phase extraction-high-performance liquid chromatography-tandem mass spectrometry.

We have developed a method using on-line solid-phase extraction-high-performance liquid chromatography-tandem mass spectrometry (SPE-HPLC-MS/MS) and isotope dilution quantification to measure atrazine and seven atrazine metabolites in urine. The metabolites measured were hydroxyatrazine, diaminochloroatrazine, desisopropylatrazine, desethylatrazine, desethylatrazine mercapturate, atrazine mercaturate and atrazine itself. Our method has good precision (relative standard deviations ranging from 4 to 20% at 5, 10 and 50 ng/mL), extraction efficiencies of 67 to 102% at 5 and 25 ng/mL, relative recoveries of 87 to 112% at 5, 25, 50 and 100 ng/mL limits of detection (LOD) ranging from 0.03 to 2.80 ng/mL. The linear range of our method spans from the analyte LOD to 100 ng/mL (40 ng/mL for atrazine and atrazine mercapturate) with R (2) values of greater than 0.999 and errors about the slope of less than 3%. Our method is rapid, cost-effective and suitable for large-scale sample analyses and is easily adaptable to other biological matrices. More importantly, this method will allow us to better assess human exposure to atrazine-related chemicals.

Assessing exposure to atrazine and its metabolites using biomonitoring.

BACKGROUND: Atrazine (ATZ) is the second most abundantly applied pesticide in the United States. When we assessed exposure to ATZ by measuring its urinary mercapturic acid metabolite, general population data indicated that < 5% of the population was exposed to ATZ-related chemicals (limit of detection < 0.8 ng/mL). OBJECTIVES: The aim of our study was to determine if we were underestimating ATZ exposure by measuring its urinary mercapturic acid metabolite and if the urinary metabole profile changed with the exposure scenario. METHODS: We conducted a small-scale study involving 24 persons classified as high- (n = 8), low(n = 5), and environmental- (n = 11) exposed to ATZ. Using online solid phase extraction high performance liquid chromatography-tandem mass spectrometry, we measured nine ATZ-related metabolites in urine that included dealkylated, hydroxylated, and mercapturic acid metabolites. RESULTS: We found that the urinary metabolite profiles varied greatly among exposure scenarios and among persons within each exposure scenario. Although diaminochlorotriazine (DACT) appeared to be the predominant urinary metabolite detected in each exposure category, the variation in proportion of total ATZ metabolites among persons was consistently large, suggesting that one metabolite alone could not be measured as a surrogate for ATZ exposure. CONCLUSIONS: We have likely been underestimating population-based exposures by measuring only one urinary ATZ metabolite. Multiple urinary metabolites must be measured to accurately classify exposure to ATZ and its environmental degradates. Regardless, DACT and desethylatrazine appear to be the most important metabolites to measure to evaluate exposures to ATZ-related chemicals.

Quantification of atrazine, phenylurea, and sulfonylurea herbicide metabolites in urine by high-performance liquid chromatography-tandem mass spectrometry.

We developed a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS-MS) method to measure metabolites of atrazine, phenylurea, and sulfonylurea herbicides in human urine. The metabolites measured in the method include atrazine mercapturate, desethyl atrazine, and desisopropyl atrazine as markers of atrazine exposure; dichlorophenyl urea, dichlorophenylmethyl urea, diuron, and linuron as markers of phenylurea herbicide exposure; and dimethoxypyrimidine, dimethylpyrimidine, and methoxymethyl triazine as markers for sulfonylurea herbicide exposure. The metabolites were extracted from urine by simple solid-phase extraction using a mixed-bed cartridge and were analyzed by HPLC-MS-MS. Quantification of the atrazine metabolites was achieved using isotope-dilution calibration. The remaining metabolites were quantified using similarly structured chemicals as internal standards. Extraction recoveries ranged from 88% to 104% (n = 5). Limits of detection for the entire method ranged from 0.125 to 1 ng/mL, and the average relative standard deviation of repeat measurements was about 13% (n = 30).