Unintended Consequences: A Case Study of a Toddler's Accidental Burn Injury Caused by a Hair Crimper.

ABSTRACT: Recognizing when an injury is concerning for abuse is of utmost importance, as failure to do so places the child at a significant risk for further inflicted injury. Misinterpreting accidental injury as abuse can also have dire consequences for a child and their caregivers. The provider must be aware of characteristics of cutaneous injuries, including burns, that are concerning for abuse. Understanding these characteristics and putting them into clinical practice is necessary to protect children from additional abuse and protect families from wrongful accusations. This case report evaluates a 12-month-old boy who presented to a pediatric emergency room with a patterned, full-thickness burn to the leg. After evaluation, we summarized the additional medical evaluation needed, including a focused history and physical examination, and recommended appropriate diagnostic testing needed to evaluate a child of this age for possible child maltreatment.

Failure to repair endogenous DNA damage in ß-cells causes adult-onset diabetes in mice.

Age is the greatest risk factor for the development of type 2 diabetes mellitus (T2DM). Age-related decline in organ function is attributed to the accumulation of stochastic damage, including damage to the nuclear genome. Islets of T2DM patients display increased levels of DNA damage. However, whether this is a cause or consequence of the disease has not been elucidated. Here, we asked if spontaneous, endogenous DNA damage in ß-cells can drive ß-cell dysfunction and diabetes, via deletion of Ercc1, a key DNA repair gene, in ß-cells. Mice harboring Ercc1-deficient ß-cells developed adult-onset diabetes as demonstrated by increased random and fasted blood glucose levels, impaired glucose tolerance, and reduced insulin secretion. The inability to repair endogenous DNA damage led to an increase in oxidative DNA damage and apoptosis in ß-cells and a significant loss of ß-cell mass. Using electron microscopy, we identified ß-cells in clear distress that showed an increased cell size, enlarged nuclear size, reduced number of mature insulin granules, and decreased number of mitochondria. Some ß-cells were more affected than others consistent with the stochastic nature of spontaneous DNA damage. Ercc1-deficiency in ß-cells also resulted in loss of ß-cell function as glucose-stimulated insulin secretion and mitochondrial function were impaired in islets isolated from mice harboring Ercc1-deficient ß-cells. These data reveal that unrepaired endogenous DNA damage is sufficient to drive ß-cell dysfunction and provide a mechanism by which age increases the risk of T2DM.

Barriers to care in juvenile localized and systemic scleroderma: an exploratory survey study of caregivers' perspectives.

BACKGROUND: Juvenile localized scleroderma (LS) and systemic sclerosis (SSc) are rare pediatric conditions often associated with severe morbidities. Delays in diagnosis are common, increasing the risk for permanent damage and worse outcomes. This study explored caregiver perspectives on barriers they encountered while navigating diagnosis and care for their child's scleroderma. METHODS: In this cross-sectional study, caregivers of juvenile LS or SSc patients were recruited from a virtual family scleroderma educational conference and a juvenile scleroderma online interest group. The survey queried respondents about their child's condition and factors affecting diagnosis and treatment. RESULTS: The response rate was 61% (73/120), with 38 parents of LS patients and 31 parents of SSc patients. Most patients were female (80%) and over half were non-Hispanic white (55%). Most families had at least one person with a college education or higher (87%), traveled ≤ 2 h to see their rheumatologist (83%), and had private insurance (75%). Almost half had an annual household income ≥ $100,000 (46%). Families identified the following factors as barriers to care: lack of knowledge about scleroderma in the medical community, finding reliable information about pediatric scleroderma, long wait times/distances for a rheumatology/specialist appointment, balance of school/work and child's healthcare needs, medication side effects, and identifying effective medications. The barrier most identified as a major problem was the lack of knowledge about juvenile scleroderma in the medical community. Public insurance, household income less than $100,000, and Hispanic ethnicity were associated with specific barriers to care. Lower socioeconomic status was associated with longer travel times to see the rheumatologist/specialist. Diagnosis and systemic treatment initiation occurred at greater than one year from initial presentation for approximately 28% and 36% of patients, respectively. Families of LS patients were commonly given erroneous information about the disease, including on the need and importance of treating active disease with systemic immunosuppressants in patients with deep tissue or rapidly progressive disease. CONCLUSION: Caregivers of children with LS or SSc reported numerous common barriers to the diagnosis, treatment, and ongoing care of juvenile scleroderma. The major problem highlighted was the lack of knowledge of scleroderma within the general medical community. Given that most of the caregiver respondents to the survey had relatively high socioeconomic status, additional studies are needed to reach a broader audience, including caregivers with limited English proficiency, geographical limitations, and financial constraints, to determine if the identified problems are generalizable. Identifying key care barriers will help direct efforts to address needs, reduce disparities in care, and improve patient outcomes.

Urinary Nicotine Metabolites and Self-Reported Tobacco Use Among Adults in the Population Assessment of Tobacco and Health (PATH) Study, 2013-2014.

INTRODUCTION: The Population Assessment of Tobacco and Health (PATH) Study is a longitudinal cohort study on tobacco use behavior, attitudes and beliefs, and tobacco-related health outcomes, including biomarkers of tobacco exposure in the U.S. population. In this report we provide a summary of urinary nicotine metabolite measurements among adult users and non-users of tobacco from Wave 1 (2013-2014) of the PATH Study. METHODS: Total nicotine and its metabolites including cotinine, trans-3'-hydroxycotinine (HCTT), and other minor metabolites were measured in more than 11 500 adult participants by liquid chromatography tandem mass spectrometry methods. Weighted geometric means (GM) and least square means from statistical modeling were calculated for non-users and users of various tobacco products. RESULTS: Among daily users, the highest GM concentrations of nicotine, cotinine and HCTT were found in exclusive smokeless tobacco users, and the lowest in exclusive e-cigarette users. Exclusive combustible product users had intermediate concentrations, similar to those found in users of multiple products (polyusers). Concentrations increased with age within the categories of tobacco users, and differences associated with gender, race/ethnicity and educational attainment were also noted among user categories. Recent (past 12 months) former users had GM cotinine concentrations that were more than threefold greater than never users. CONCLUSIONS: These urinary nicotine metabolite data provide quantification of nicotine exposure representative of the entire US adult population during 2013-2014 and may serve as a reference for similar analyses in future measurements within this study. IMPLICATIONS: Nicotine and its metabolites in urine provide perhaps the most fundamental biomarkers of recent nicotine exposure. This report, based on Wave 1 of the Population Assessment of Tobacco and Health (PATH) Study, provides the first nationally representative data describing urinary nicotine biomarker concentrations in both non-users, and users of a variety of tobacco products including combustible, e-cigarette and smokeless products. These data provide a urinary biomarker concentration snapshot in time for the entire US population during 2013-2014, and will provide a basis for comparison with future results from continuing, periodic evaluations in the PATH Study.

An aged immune system drives senescence and ageing of solid organs.

Ageing of the immune system, or immunosenescence, contributes to the morbidity and mortality of the elderly1,2. To define the contribution of immune system ageing to organism ageing, here we selectively deleted Ercc1, which encodes a crucial DNA repair protein3,4, in mouse haematopoietic cells to increase the burden of endogenous DNA damage and thereby senescence5-7 in the immune system only. We show that Vav-iCre+/-;Ercc1-/fl mice were healthy into adulthood, then displayed premature onset of immunosenescence characterized by attrition and senescence of specific immune cell populations and impaired immune function, similar to changes that occur during ageing in wild-type mice8-10. Notably, non-lymphoid organs also showed increased senescence and damage, which suggests that senescent, aged immune cells can promote systemic ageing. The transplantation of splenocytes from Vav-iCre+/-;Ercc1-/fl or aged wild-type mice into young mice induced senescence in trans, whereas the transplantation of young immune cells attenuated senescence. The treatment of Vav-iCre+/-;Ercc1-/fl mice with rapamycin reduced markers of senescence in immune cells and improved immune function11,12. These data demonstrate that an aged, senescent immune system has a causal role in driving systemic ageing and therefore represents a key therapeutic target to extend healthy ageing.

Tobacco-Specific Nitrosamines (NNAL, NNN, NAT, and NAB) Exposures in the US Population Assessment of Tobacco and Health (PATH) Study Wave 1 (2013-2014).

INTRODUCTION: The tobacco-specific nitrosamines (TSNAs) are an important group of carcinogens found in tobacco and tobacco smoke. To describe and characterize the levels of TSNAs in the Population Assessment of Tobacco and Health (PATH) Study Wave 1 (2013-2014), we present four biomarkers of TSNA exposure: N'-nitrosonornicotine, N'-nitrosoanabasine, N'-nitrosoanatabine, and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) which is the primary urinary metabolite of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone. METHODS: We measured total TSNAs in 11 522 adults who provided urine using automated solid-phase extraction coupled to isotope dilution liquid chromatography-tandem mass spectrometry. After exclusions in this current analysis, we selected 11 004 NNAL results, 10 753 N'-nitrosonornicotine results, 10 919 N'-nitrosoanatabine results, and 10 996 N'-nitrosoanabasine results for data analysis. Geometric means and correlations were calculated using SAS and SUDAAN. RESULTS: TSNA concentrations were associated with choice of tobacco product and frequency of use. Among established, every day, exclusive tobacco product users, the geometric mean urinary NNAL concentration was highest for smokeless tobacco users (993.3; 95% confidence interval [CI: 839.2, 1147.3] ng/g creatinine), followed by all types of combustible tobacco product users (285.4; 95% CI: [267.9, 303.0] ng/g creatinine), poly tobacco users (278.6; 95% CI: [254.9, 302.2] ng/g creatinine), and e-cigarette product users (6.3; 95% CI: [4.7, 7.9] ng/g creatinine). TSNA concentrations were higher in every day users than in intermittent users for all the tobacco product groups. Among single product users, exposure to TSNAs differed by sex, age, race/ethnicity, and education. Urinary TSNAs and nicotine metabolite biomarkers were also highly correlated. CONCLUSIONS: We have provided PATH Study estimates of TSNA exposure among US adult users of a variety of tobacco products. These data can inform future tobacco product and human exposure evaluations and related regulatory activities.

Tissue specificity of senescent cell accumulation during physiologic and accelerated aging of mice.

Senescent cells accumulate with age in vertebrates and promote aging largely through their senescence-associated secretory phenotype (SASP). Many types of stress induce senescence, including genotoxic stress. ERCC1-XPF is a DNA repair endonuclease required for multiple DNA repair mechanisms that protect the nuclear genome. Humans or mice with reduced expression of this enzyme age rapidly due to increased levels of spontaneous, genotoxic stress. Here, we asked whether this corresponds to an increased level of senescent cells. p16Ink4a and p21Cip1 mRNA were increased ~15-fold in peripheral lymphocytes from 4- to 5-month-old Ercc1-/∆ and 2.5-year-old wild-type (WT) mice, suggesting that these animals exhibit a similar biological age. p16Ink4a and p21Cip1 mRNA were elevated in 10 of 13 tissues analyzed from 4- to 5-month-old Ercc1-/∆ mice, indicating where endogenous DNA damage drives senescence in vivo. Aged WT mice had similar increases of p16Ink4a and p21Cip1 mRNA in the same 10 tissues as the mutant mice. Senescence-associated ß-galactosidase activity and p21Cip1 protein also were increased in tissues of the progeroid and aged mice, while Lamin B1 mRNA and protein levels were diminished. In Ercc1-/Δ mice with a p16Ink4a luciferase reporter, bioluminescence rose steadily with age, particularly in lung, thymus, and pancreas. These data illustrate where senescence occurs with natural and accelerated aging in mice and the relative extent of senescence among tissues. Interestingly, senescence was greater in male mice until the end of life. The similarities between Ercc1-/∆ and aged WT mice support the conclusion that the DNA repair-deficient mice accurately model the age-related accumulation of senescent cells, albeit six-times faster.

Fisetin is a senotherapeutic that extends health and lifespan.

BACKGROUND: Senescence is a tumor suppressor mechanism activated in stressed cells to prevent replication of damaged DNA. Senescent cells have been demonstrated to play a causal role in driving aging and age-related diseases using genetic and pharmacologic approaches. We previously demonstrated that the combination of dasatinib and the flavonoid quercetin is a potent senolytic improving numerous age-related conditions including frailty, osteoporosis and cardiovascular disease. The goal of this study was to identify flavonoids with more potent senolytic activity. METHODS: A panel of flavonoid polyphenols was screened for senolytic activity using senescent murine and human fibroblasts, driven by oxidative and genotoxic stress, respectively. The top senotherapeutic flavonoid was tested in mice modeling a progeroid syndrome carrying a p16INK4a-luciferase reporter and aged wild-type mice to determine the effects of fisetin on senescence markers, age-related histopathology, disease markers, health span and lifespan. Human adipose tissue explants were used to determine if results translated. FINDINGS: Of the 10 flavonoids tested, fisetin was the most potent senolytic. Acute or intermittent treatment of progeroid and old mice with fisetin reduced senescence markers in multiple tissues, consistent with a hit-and-run senolytic mechanism. Fisetin reduced senescence in a subset of cells in murine and human adipose tissue, demonstrating cell-type specificity. Administration of fisetin to wild-type mice late in life restored tissue homeostasis, reduced age-related pathology, and extended median and maximum lifespan. INTERPRETATION: The natural product fisetin has senotherapeutic activity in mice and in human tissues. Late life intervention was sufficient to yield a potent health benefit. These characteristics suggest the feasibility to translation to human clinical studies. FUND: NIH grants P01 AG043376 (PDR, LJN), U19 AG056278 (PDR, LJN, WLL), R24 AG047115 (WLL), R37 AG013925 (JLK), R21 AG047984 (JLK), P30 DK050456 (Adipocyte Subcore, JLK), a Glenn Foundation/American Federation for Aging Research (AFAR) BIG Award (JLK), Glenn/AFAR (LJN, CEB), the Ted Nash Long Life and Noaber Foundations (JLK), the Connor Group (JLK), Robert J. and Theresa W. Ryan (JLK), and a Minnesota Partnership Grant (AMAY-UMN#99)-P004610401-1 (JLK, EAA).

Neurodegeneration as the presenting symptom in 2 adults with xeroderma pigmentosum complementation group F.

OBJECTIVE: To describe the features of 2 unrelated adults with xeroderma pigmentosum complementation group F (XP-F) ascertained in a neurology care setting. METHODS: We report the clinical, imaging, molecular, and nucleotide excision repair (NER) capacity of 2 middle-aged women with progressive neurodegeneration ultimately diagnosed with XP-F. RESULTS: Both patients presented with adult-onset progressive neurologic deterioration involving chorea, ataxia, hearing loss, cognitive deficits, profound brain atrophy, and a history of skin photosensitivity, skin freckling, and/or skin neoplasms. We identified compound heterozygous pathogenic mutations in ERCC4 and confirmed deficient NER capacity in skin fibroblasts from both patients. CONCLUSIONS: These cases illustrate the role of NER dysfunction in neurodegeneration and how adult-onset neurodegeneration could be the major symptom bringing XP-F patients to clinical attention. XP-F should be considered by neurologists in the differential diagnosis of patients with adult-onset progressive neurodegeneration accompanied by global brain atrophy and a history of heightened sun sensitivity, excessive freckling, and skin malignancies.

ERCC4 variants identified in a cohort of patients with segmental progeroid syndromes.

Pathogenic variants in genes, which encode DNA repair and damage response proteins, result in a number of genomic instability syndromes with features of accelerated aging. ERCC4 (XPF) encodes a protein that forms a complex with ERCC1 and is required for the 5' incision during nucleotide excision repair. ERCC4 is also FANCQ, illustrating a critical role in interstrand crosslink repair. Pathogenic variants in this gene cause xeroderma pigmentosum, XFE progeroid syndrome, Cockayne syndrome (CS), and Fanconi anemia. We performed massive parallel sequencing for 42 unsolved cases submitted to the International Registry of Werner Syndrome. Two cases, each carrying two novel heterozygous ERCC4 variants, were identified. The first case was a compound heterozygote for: c.2395C > T (p.Arg799Trp) and c.388+1164_792+795del (p.Gly130Aspfs*18). Further molecular and cellular studies indicated that the ERCC4 variants in this patient are responsible for a phenotype consistent with a variant of CS. The second case was heterozygous for two variants in cis: c.[1488A > T; c.2579C > A] (p.[Gln496His; Ala860Asp]). While the second case also had several phenotypic features of accelerated aging, we were unable to provide biological evidence supporting the pathogenic roles of the associated ERCC4 variants. Precise genetic causes and disease mechanism of the second case remains to be determined.

Semi-automated solid phase extraction method for the mass spectrometric quantification of 12 specific metabolites of organophosphorus pesticides, synthetic pyrethroids, and select herbicides in human urine.

Organophosphate and pyrethroid insecticides and phenoxyacetic acid herbicides represent important classes of pesticides applied in commercial and residential settings. Interest in assessing the extent of human exposure to these pesticides exists because of their widespread use and their potential adverse health effects. An analytical method for measuring 12 biomarkers of several of these pesticides in urine has been developed. The target analytes were extracted from one milliliter of urine by a semi-automated solid phase extraction technique, separated from each other and from other urinary biomolecules by reversed-phase high performance liquid chromatography, and detected using tandem mass spectrometry with isotope dilution quantitation. This method can be used to measure all the target analytes in one injection with similar repeatability and detection limits of previous methods which required more than one injection. Each step of the procedure was optimized to produce a robust, reproducible, accurate, precise and efficient method. The required selectivity and sensitivity for trace-level analysis (e.g., limits of detection below 0.5ng/mL) was achieved using a narrow diameter analytical column, higher than unit mass resolution for certain analytes, and stable isotope labeled internal standards. The method was applied to the analysis of 55 samples collected from adult anonymous donors with no known exposure to the target pesticides. This efficient and cost-effective method is adequate to handle the large number of samples required for national biomonitoring surveys.

Quantification of melamine in human urine using cation-exchange based high performance liquid chromatography tandem mass spectrometry.

Melamine and cyanuric acid have been implicated as adulterants in baby formula in China and pet foods in North America. In China, the effect of melamine or melamine-cyanuric acid adulteration lead to kidney stone development and acute renal failure in thousands of Chinese infants. A selective and sensitive analytical method was developed to measure melamine in human urine in order to evaluate the extent of potential health implications resulting from the consumption of these types of adulterated products in the general US population. This method involves extracting melamine from human urine using cation-exchange solid-phase extraction, chromatographically separating it from its urinary matrix co-extractants on a silica-based, strong-cation exchange analytical column using high performance liquid chromatography, and analysis using positive mode electrospray ionization tandem mass spectrometry. Quantification was performed using modified, matrix-based isotope dilution calibration covering the concentration range of 0.50-100 ng/mL. The limit of detection, calculated using replicates of blank and low level spiked samples, was 0.66 ng/mL and the relative standard deviations were between 6.89 and 14.9%. The relative recovery of melamine was 101-106%. This method was tested for viability by analyzing samples collected from the general US population. Melamine was detected in 76% of the samples tested, with a geometric mean of 2.37 ng/mL, indicating that this method is suitable for reliably detecting background exposures to melamine or other chemicals from which it can be derived.

Quantification of cyanuric acid residue in human urine using high performance liquid chromatography-tandem mass spectrometry.

Concern has increased about the resulting health effects of exposure to melamine and its metabolic contaminant, cyanuric acid, after infants in China were fed baby formula milk products contaminated with these compounds. We have developed a selective and sensitive analytical method to quantify the amount of cyanuric acid in human urine. The sample preparation involved extracting free-form cyanuric acid in human urine using anion exchange solid phase extraction. Cyanuric acid was separated from its urinary matrix components on the polymeric strong anion exchange analytical column; the analysis was performed by high performance liquid chromatography-tandem mass spectrometry using negative mode electrospray ionization interface. Quantification was performed using isotope dilution calibration covering the concentration range of 1.00-200ng/mL. The limit of detection was 0.60ng/mL and the relative standard deviations were 2.8-10.5% across the calibration range. The relative recovery of cyanuric acid was 100-104%. Our method is suitable to detect urinary concentrations of cyanuric acid caused by either environmental exposures or emerging poisoning events.

Maribavir: a novel antiviral agent with activity against cytomegalovirus.

OBJECTIVE: To review the pharmacology, pharmacokinetics, efficacy, and safety of maribavir, a novel antiviral agent in the benzimidazole drug class. DATA SOURCES: Articles were identified through searches of MEDLINE (January 1998-July 2008). Abstracts from recent scientific meetings and the manufacturer were also included. STUDY SELECTION AND DATA EXTRACTION: All English-language in vitro and in vivo studies and abstracts evaluating maribavir were reviewed and considered for inclusion. All human studies were included. DATA SYNTHESIS: Maribavir has significant activity against both human cytomegalovirus (CMV) and Epstein-Barr virus, but not other herpesviruses. Unlike ganciclovir, which needs to be phosphorylated by UL 97 kinase to become an active inhibitor of DNA polymerase, maribavir directly inhibits UL 97 kinase. UL 97 kinase is an early viral gene product involved in viral DNA elongation, DNA packaging, and egress or shedding of capsids from viral nuclei. Maribavir has also been found to be effective against ganciclovir-resistant CMV strains. Maribavir differs from current CMV antiviral agents in its adverse event profile. Maribavir is not associated with nephrotoxicity or hematologic toxicities, but has been associated with taste disturbances. In February 2007, maribavir was granted Food and Drug Administration orphan drug status for prevention of CMV viremia and diseases in at-risk populations. Maribavir Phase 2 trials in stem-cell transplant recipients have been completed, and there are ongoing Phase 3 trials in stem-cell and organ transplant recipients. CONCLUSIONS: Maribavir may be an option for treatment of ganciclovir-resistant CMV infections. Its bioavailability is greater than that of oral ganciclovir, but less than that of valganciclovir. No differences in pharmacokinetics were seen in renally impaired patients, although dialysis-dependent patients were not evaluated. Maribavir is not associated with hematologic toxicities; however, the high prevalence of taste disturbances may limit its tolerability.

Experience with antibody-mediated rejection in kidney allograft recipients.

In our case series, AMR occurred in patients who had DSA. Twelve of the 21 patients (57%) who developed de novo antibodies post-transplant had biopsy-proven episodes of either rejection (of any Banff classification) and/or chronic allograft nephropathy. Only one-third of these 12 patients with rejection episodes were classified as AMR. It is unclear when and how often measurements for DSA should be performed after transplantation. When AMR is suspected, the detection of anti-HLA antibodies should be done using very sensitive assays. An increase in PRA and/or the detection of anti-HLA antibodies specific to previous sensitization events may precede an episode of AMR, even in the absence of DSA. Prospective clinical trials are needed to assess the predictive value of the presence of DSA after transplant. It is uncertain which therapeutic response should follow after the detection of these antibody responses in the absence of clinical symptoms. AMR requires intensive therapy, but no standard treatment has been established. Three patients who had AMR at our center were treated with rituximab in addition to various combinations of plasmapheresis, methylprednisolone, OKT3, and intravenous immune globulin. Only one patient responded to this treatment. Well-controlled clinical trials would help to evaluate the efficacy and benefit of B-cell depletion in combination with other immunosuppressive agents.