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We present a case of Streptococcus equi subsp. equi meningitis in a young boy. This case represents the first report in the literature of meningitis caused by this organism, as far as we know. [ABSTRACT FROM AUTHOR]

Objectives: Complement factor I (CFI) deficiency is a rare autosomal recessive inborn error of immunity. In this report, we highlight that complete CFI deficiency may present with isolated and severe CNS inflammation without associated systemic features nor prior non-CNS episodes. This inflammation may respond to complement blockade therapy., Methods: This is a case description of a young girl with severe longitudinal transverse myelitis treated with aggressive immunotherapy that included eculizumab. Published cases of CFI-associated CNS inflammation were reviewed and discussed., Results: A primary immunodeficiency panel revealed 2 germline pathogenic variants in the CFI gene. Further complement testing of the index case and her family confirmed complete CFI deficiency., Discussion: We describe a unique case of severe spinal inflammation secondary to complete CFI deficiency. Although rare, isolated CNS inflammation may be the primary manifestation of complete CFI deficiency. To halt the uncontrolled complement-mediated inflammation associated with CFI deficiency, prompt targeted blockade of the complement pathway using eculizumab may be life changing in the acute phase. Long-lasting blockade of the complement pathway is also essential to prevent relapse in this subgroup of patients.

Background: The protective effect of community water fluoridation (CWF) against dental caries may be modified by secular changes in health behaviour. We aimed to determine the contemporary association between fluoride in public water supplies (PWS) and dental caries indicators and inequalities in England., Methods: We estimated exposure to CWF and PWS fluoride concentrations from national monitoring data, using Geographic Information Systems and water supply boundaries, categorizing mean period exposure into <0.1, 0.1-<0.2, 0.2-<0.4, 0.4-<0.7 and ≥0.7 mg/l. We used area-level health outcome and confounder data in multivariable regression models to determine the association between fluoride and caries outcomes and calculated preventive fractions using these coefficients., Results: The odds of caries and of severe caries in 5-year-olds fell with increasing fluoride concentration in all SES quintiles (P < 0.001 to P = 0.003). There was a negative trend between increasing fluoride concentration and dental extractions (P < 0.001). Compared to PWS with <0.2 mg/l, CWF prevented 17% (95% confidence interval (CI): 5-27%) to 28% (95% CI: 24-32%) of caries (high-low SES) and 56% (95% CI: 25-74%) of dental extractions. The association between fluoride concentration and caries prevalence/severity varied by socioeconomic status (SES) (P < 0.001)., Conclusions: Exposure to fluoride in PWS appears highly protective against dental caries and reduces oral health inequalities., (© The Author(s) 2022. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Acute Central Nervous System (CNS) Graft Versus Host Disease (GvHD) is a rare form of GvHD, only described in case reports. Knowledge about this condition is extrapolated from chronic CNS GvHD cases occurring mostly after hematopoietic stem cell transplantation. GvHD following solid organ transplantation is an unexpected complication. GvHD after liver transplantation has a poor prognosis, and the optimal management is not yet known. Here we describe the case of a 63-year-old man who underwent deceased donor liver transplantation and subsequently developed skin rash, colitis and pancytopenia followed by refractory status epilepticus. Following the identification of lymphocytes of donor origin in the cerebrospinal fluid of the patient, he was diagnosed with acute CNS GvHD. He was treated with an intensive immunosuppressive regimen, but care was withdrawn due to lack of improvement and worsening neurologic prognosis. It is the second known case of acute CNS GvHD following liver transplantation. Clinicians should be aware of this possible, although rare, complication of liver transplantation, especially when there is refractory status epilepticus of unknown origin., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background & Aims: We recently showed that alcoholic hepatitis (AH) is characterized by dedifferentiation of hepatocytes and loss of mature functions. Glucose metabolism is tightly regulated in healthy hepatocytes. We hypothesize that AH may lead to metabolic reprogramming of the liver, including dysregulation of glucose metabolism., Methods: We performed integrated metabolomic and transcriptomic analyses of liver tissue from patients with AH or alcoholic cirrhosis or normal liver tissue from hepatic resection. Focused analyses of chromatin immunoprecipitation coupled to DNA sequencing was performed. Functional in vitro studies were performed in primary rat and human hepatocytes and HepG2 cells., Results: Patients with AH exhibited specific changes in the levels of intermediates of glycolysis/gluconeogenesis, the tricarboxylic acid cycle, and monosaccharide and disaccharide metabolism. Integrated analysis of the transcriptome and metabolome showed the used of alternate energetic pathways, metabolite sinks and bottlenecks, and dysregulated glucose storage in patients with AH. Among genes involved in glucose metabolism, hexokinase domain containing 1 (HKDC1) was identified as the most up-regulated kinase in patients with AH. Histone active promoter and enhancer markers were increased in the HKDC1 genomic region. High HKDC1 levels were associated with the development of acute kidney injury and decreased survival. Increased HKDC1 activity contributed to the accumulation of glucose-6-P and glycogen in primary rat hepatocytes., Conclusions: Altered metabolite levels and messenger RNA expression of metabolic enzymes suggest the existence of extensive reprogramming of glucose metabolism in AH. Increased HKDC1 expression may contribute to dysregulated glucose metabolism and represents a novel biomarker and therapeutic target for AH., (Copyright © 2021. Published by Elsevier Inc.)

Human alcoholism and ethanol exposure of adult mice cause acute microbial dysbiosis. Adolescent binge drinking is common, but the effect of adolescent ethanol exposure on the adult microbiome and enteric neurotransmitters has not been studied. In the current study, male Wistar rats received adolescent intermittent ethanol (AIE) treatment, and fecal samples were collected on postnatal day (P)54 and P95 for bacterial 16S rRNA amplicon sequencing. Cecal tissue was collected on P95 for analysis of innate immune and neurotransmitter marker expression. At the genus level, AIE treatment altered the relative abundance of several microbes, including decreased relative abundance of Dehalobacterium and CF231 (a member of the Paraprevotellaceae family) that persisted into adulthood. Across aging, the relative abundance of several microbes was altered in both control- and AIE-treated rats. At P95, AIE exposure was associated with increased cecal serotonin levels and reduced choline acetyltransferase gene expression. Taxonomic shifts at P54 and at P95 suggest that AIE causes both immediate and lasting microbial dysbiosis. The lasting microbial dysbiosis was accompanied by alterations of enteric neurotransmitters., (© 2019 Society for the Study of Addiction.)

Advanced fibrosis and portal hypertension influence short-term mortality. Lipocalin 2 (LCN2) regulates infection response and increases in liver injury. We explored the role of intrahepatic LCN2 in human alcoholic hepatitis (AH) with advanced fibrosis and portal hypertension and in experimental mouse fibrosis. We found hepatic LCN2 expression and serum LCN2 level markedly increased and correlated with disease severity and portal hypertension in patients with AH. In control human livers, LCN2 expressed exclusively in mononuclear cells, while its expression was markedly induced in AH livers, not only in mononuclear cells but also notably in hepatocytes. Lcn2 -/- mice were protected from liver fibrosis caused by either ethanol or CCl 4 exposure. Microarray analysis revealed downregulation of matrisome, cell cycle and immune related gene sets in Lcn2 -/- mice exposed to CCl 4 , along with decrease in Timp1 and Edn1 expression. Hepatic expression of COL1A1, TIMP1 and key EDN1 system components were elevated in AH patients and correlated with hepatic LCN2 expression. In vitro, recombinant LCN2 induced COL1A1 expression. Overexpression of LCN2 increased HIF1A that in turn mediated EDN1 upregulation. LCN2 contributes to liver fibrosis and portal hypertension in AH and could represent a new therapeutic target.

In non-alcoholic steatohepatitis (NASH), many lines of investigation have reported a dysregulation in lipid homeostasis, leading to intrahepatic lipid accumulation. Recently, the role of dysfunctional sphingolipid metabolism has also been proposed. Human and animal models of NASH have been associated with elevated levels of long chain ceramides and pro-apoptotic sphingolipid metabolites, implicated in regulating fatty acid oxidation and inflammation. Importantly, inhibition of de novo ceramide biosynthesis or knock-down of ceramide synthases reverse some of the pathology of NASH. In contrast, cell permeable, short chain ceramides have shown anti-inflammatory actions in multiple models of inflammatory disease. Here, we investigated non-apoptotic doses of a liposome containing short chain C6-Ceramide (Lip-C6) administered to human hepatic stellate cells (hHSC), a key effector of hepatic fibrogenesis, and an animal model characterized by inflammation and elevated liver fat content. On the basis of the results from unbiased liver transcriptomic studies from non-alcoholic fatty liver disease patients, we chose to focus on adenosine monophosphate activated kinase (AMPK) and nuclear factor-erythroid 2-related factor (Nrf2) signaling pathways, which showed an abnormal profile. Lip-C6 administration inhibited hHSC proliferation while improving anti-oxidant protection and energy homeostasis, as indicated by upregulation of Nrf2, activation of AMPK and an increase in ATP. To confirm these in vitro data, we investigated the effect of a single tail-vein injection of Lip-C6 in the methionine-choline deficient (MCD) diet mouse model. Lip-C6, but not control liposomes, upregulated phospho-AMPK, without inducing liver toxicity, apoptosis, or exacerbating inflammatory signaling pathways. Alluding to mechanism, mass spectrometry lipidomics showed that Lip-C6-treatment reversed the imbalance in hepatic phosphatidylcholines and diacylglycerides species induced by the MCD-fed diet. These results reveal that short-term Lip-C6 administration reverses energy/metabolic depletion and increases protective anti-oxidant signaling pathways, possibly by restoring homeostatic lipid function in a model of liver inflammation with fat accumulation.

Alcoholic hepatitis (AH) is a life-threatening condition characterized by profound hepatocellular dysfunction for which targeted treatments are urgently needed. Identification of molecular drivers is hampered by the lack of suitable animal models. By performing RNA sequencing in livers from patients with different phenotypes of alcohol-related liver disease (ALD), we show that development of AH is characterized by defective activity of liver-enriched transcription factors (LETFs). TGFβ1 is a key upstream transcriptome regulator in AH and induces the use of HNF4α P2 promoter in hepatocytes, which results in defective metabolic and synthetic functions. Gene polymorphisms in LETFs including HNF4α are not associated with the development of AH. In contrast, epigenetic studies show that AH livers have profound changes in DNA methylation state and chromatin remodeling, affecting HNF4α-dependent gene expression. We conclude that targeting TGFβ1 and epigenetic drivers that modulate HNF4α-dependent gene expression could be beneficial to improve hepatocellular function in patients with AH.

Background & Aims: Sterile inflammation resulting in alcoholic hepatitis (AH) occurs unpredictably after many years of excess alcohol intake. The factors responsible for the development of AH are not known but mitochondrial damage with loss of mitochondrial function are common features. Hcar2 is a G-protein coupled receptor which is activated by β-hydroxybutyrate (BHB). We aimed to determine the relevance of the BHB-Hcar2 pathway in alcoholic liver disease., Methods: We tested if loss of BHB production can result in increased liver inflammation. We further tested if BHB supplementation is protective in AH through interaction with Hcar2, and analyzed the immune and cellular basis for protection., Results: Humans with AH have reduced hepatic BHB, and inhibition of BHB production in mice aggravated ethanol-induced AH, with higher plasma alanine aminotransferase levels, increased steatosis and greater neutrophil influx. Conversely supplementation of BHB had the opposite effects with reduced alanine aminotransferase levels, reduced steatosis and neutrophil influx. This therapeutic effect of BHB is dependent on the receptor Hcar2. BHB treatment increased liver Il10 transcripts, and promoted the M2 phenotype of intrahepatic macrophages. BHB also increased the transcriptional level of M2 related genes in vitro bone marrow derived macrophages. This skewing towards M2 related genes is dependent on lower mitochondrial membrane potential (Δψ) induced by BHB., Conclusions: Collectively, our data shows that BHB production during excess alcohol consumption has an anti-inflammatory and hepatoprotective role through an Hcar2 dependent pathway. This introduces the concept of metabolite-based therapy for AH., Lay Summary: Alcoholic hepatitis is a life-threatening condition with no approved therapy that occurs unexpectedly in people who consume excess alcohol. The liver makes many metabolites, and we demonstrate that loss of one such metabolite β-hydroxybutyrate occurs in patients with alcoholic hepatitis. This loss can increase alcohol-induced liver injury, and β-hydroxybutyrate can protect from alcohol-induced liver injury via a receptor on liver macrophages. This opens the possibility of metabolite-based therapy for alcoholic hepatitis., (Copyright © 2018 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Competing Interests: Disclosure The authors report no conflicts of interest in this work.

BackgroundChildren and adolescents with Fetal Alcohol Spectrum Disorders (FASD) exhibit a range of physical, cognitive, behavioral, and/or learning deficits, as wells as poor executive functioning (EF). Children and adolescents with FASD often show greater impairments on complex neuropsychological tasks. However, little is known about age-related differences among children and adolescents with FASD.ObjectivesThe goals of this cross-sectional study were to explore the overall profile of neuropsychological impairments and extended previous reports on age-related differences among children and adolescents with FASD. MethodWe compared 117 children and adolescents diagnosed with an FASD (aged 5-17 years), clinically assessed on a broad range of tests covering 6 neurobehavioral domains. Data from a clinical database was used to generate profiles of neuropsychological impairments for clinically referred children and adolescents evaluated for FASD between 2001 and 2005. ResultsChildren and adolescents were impaired (relative to the norm) on a number of domains that include academic achievement, language, verbal memory, EF, visual-motor integration, and motor abilities. Older participants with FASD (relative to the norm) showed greater difficulty in areas involving EF or processing of complex information than younger participants. ConclusionsThese results suggest that for children and adolescents with FASD impairments in those areas important for independent functioning may become more pronounced with increasing age. However, further longitudinal research is needed to ascertain age changes over time.

Dose-intensified treatment strategies for Hodgkin lymphoma (HL) have demonstrated improvements in cure but may increase risk for acute and long-term toxicities, particularly in children. The Children's Oncology Group assessed the feasibility of a dose-intensive regimen, BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, prednisone) in children with high-risk HL (stage IIB or IIIB with bulk disease, stage IV). Rapidity of response was assessed after 4 cycles of BEACOPP. Rapid responders received consolidation therapy with guidelines to reduce the risk of sex-specific long-term toxicities of therapy. Females received 4 cycles of COPP/ABV (cyclophosphamide, vincristine, procarbazine, prednisone, doxorubicin, bleomycin, vinblastine) without involved field radiation therapy (IFRT). Males received 2 cycles of ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) with IFRT. Slow responders received 4 cycles of BEACOPP and IFRT. Ninety-nine patients were enrolled. Myelosuppression was frequent. Rapid response was achieved by 74% of patients. Five-year event-free-survival is 94%, IFRT with median follow-up of 6.3 years. There were no disease progressions on study therapy. Secondary leukemias occurred in 2 patients. Overall survival is 97%. Early intensification followed by less intense response-based therapy for rapidly responding patients is an effective strategy for achieving high event-free survival in children with high-risk HL. This trial is registered at http://www.clinicaltrials.gov as #NCT00004010., (© 2011 by The American Society of Hematology)

The purpose of the present study was to determine the association between smoking and body weight in a cohort of young U.S. Air Force recruits (mean age=20 years) enrolled in basic military training (N=35986). Twenty-two percent of recruits smoked daily prior to basic military training (n=8087) and were compared to never smokers, former smokers, and experimental or nondaily smokers. A three-way interaction among smoking status, gender and ethnicity suggested a small effect for daily smoking among White male recruits only and no significant differences for female recruits or members of any other ethnic group. Although there was a statistically significant relationship between smoking and body weight in White males, the effect size was approximately 1 kg. These results suggest that the energy balance differences in body weight between young smokers and nonsmokers are minimal and that it would take decades to accrue the differences typically seen in adult smokers.

Background: Previous research indicates that children with FASD have both memory and learning deficits. However, there is no consensus about whether the deficits identified from a pattern of impairment, and whether this pattern is consistent with the current theories regarding the organization of memory. Thus, the goal of this study was to further explore memory functions and expose possible patterns that may exist in children with FASD., Methods: The Children's Memory Scale (CMS) was used to measure visual and verbal memory, as well as learning and encoding, among 30 children with FASD (ages 9-16 years). Functioning was conceptualized through use of a model of working memory., Results: A significant difference between types of verbal memory in the FASD sample was identified. Specifically, recall of word pairs was found to be more impaired than that for stories. In addition to this, recall of immediate word pairs was significantly more impaired than that for delayed word pairs, implying the presence of encoding deficits in this area., Conclusions: Children and adolescents with FASD displayed specific types of verbal memory deficits and these deficits were greater for immediate rather than delayed memory. These data are consistent with previous studies that describe deficits in immediate memory, and suggest that deficits in delayed memory are better accounted for by encoding deficits. Furthermore, their greatest difficulty arose with those items in which the phonological loop was required, which would have facilitated learning though internal recitation and adequate phonological storage. Further research into these distinctions in memory is warranted, as is exploration into educational techniques that could account for delayed encoding in children with FASD.

p-Hydroxybenzoate hydroxylase (PHBH) is a homodimeric enzyme in which each subunit noncovalently binds one molecule of FAD in the active site. PHBH is a model system for how flavoenzymes regulate reactions with oxygen. We report single-molecule fluorescence studies of PHBH in the absence of substrate that provide data consistent with the hypothesis that a critical step in substrate binding is the movement of the isoalloxazine between an "in" conformation and a more exposed or "open" conformation. The isoalloxazine is observed to move between these conformations in the absence of substrate. Studies with the Y222A mutant form of PHBH suggest that the exposed conformation is fluorescent while the in-conformation is quenched. Finally, we note that many of the single-molecule-fluorescence trajectories reveal a conformational heterogeneity, with populations of the enzyme characterized by either fast or slow switching between the in- and open-conformations. Our data also allow us to hypothesize a model in which one flavin in the dimer inhibits the motion of the other.

2-Methyl-3-hydroxypyridine-5-carboxylic acid (MHPC) oxygenase (MHPCO) is a flavoprotein that catalyzes the oxygenation of MHPC to form alpha-(N-acetylaminomethylene)-succinic acid. Although formally similar to the oxygenation reactions catalyzed by phenol hydroxylases, MHPCO catalyzes the oxygenation of a pyridyl derivative rather than a simple phenol. Therefore, in this study, the mechanism of the reaction was investigated by replacing the natural cofactor FAD with FAD analogues having various substituents (-Cl, -CN, -NH(2), -OCH(3)) at the C8-position of the isoalloxazine. Thermodynamic and catalytic properties of the reconstituted enzyme were investigated and found to be similar to those of the native enzyme, validating that these FAD analogues are reasonable to be used as mechanistic probes. Dissociation constants for the binding of MHPC or the substrate analogue 5-hydroxynicotinate (5HN) to the reconstituted enzymes indicate that the reconstituted enzymes bind well with ligands. Redox potential values of the reconstituted enzymes were measured and found to be more positive than the values of free FAD analogues, which correlated well with the electronic effects of the 8-substituents. Studies of the reductive half-reaction of MHPCO have shown that the rates of flavin reduction by NADH could be described as a parabolic relationship with the redox potential values of the reconstituted enzymes, which is consistent with the Marcus electron transfer theory. Studies of the oxidative half-reaction of MHPCO revealed that the rate of hydroxylation depended upon the different analogues employed. The rate constants for the hydroxylation step correlated with the calculated pK(a) values of the 8-substituted C(4a)-hydroxyflavin intermediates, which are the leaving groups in the oxygen transfer step. It was observed that the rates of hydroxylation were greater when the pK(a) values of C(4a)-hydroxyflavins were lower. Although these results are not as dramatic as those from analogous studies with parahydroxybenzoate hydroxylase (Ortiz-Maldonado et al., (1999) Biochemistry 38, 8124-8137), they are consistent with the model that the oxygenation reaction of MHPCO occurs via an electrophilic aromatic substitution mechanism analogous to the mechanisms for parahydroxybenzoate and phenol hydroxylases.

Drosophila melanogaster thioredoxin reductase-1 (DmTrxR-1) is a key flavoenzyme in dipteran insects, where it substitutes for glutathione reductase. DmTrxR-1 belongs to the family of dimeric, high Mr thioredoxin reductases, which catalyze reduction of thioredoxin by NADPH. Thioredoxin reductase has an N-terminal redox-active disulfide (Cys57-Cys62) adjacent to the flavin and a redox-active C-terminal cysteine pair (Cys489'-Cys490' in the other subunit) that transfer electrons from Cys57-Cys62 to the substrate thioredoxin. Cys489'-Cys490' functions similarly to Cys495-Sec496 (Sec = selenocysteine) and Cys535-XXXX-Cys540 in human and parasite Plasmodium falciparum enzymes, but a catalytic redox center formed by adjacent Cys residues, as observed in DmTrxR-1, is unprecedented. Our data show, for the first time in a high Mr TrxR, that DmTrxR-1 oscillates between the 2-electron reduced state, EH2, and the 4-electron state, EH4, in catalysis, after the initial priming reduction of the oxidized enzyme (Eox) to EH2. The reductive half-reaction consumes 2 eq of NADPH in two observable steps to produce EH4. The first equivalent yields a FADH--NADP+ charge-transfer complex that reduces the adjacent disulfide to form a thiolate-flavin charge-transfer complex. EH4 reacts with thioredoxin rapidly to produce EH2. In contrast, Eox formation is slow and incomplete; thus, EH2 of wild-type cannot reduce thioredoxin at catalytically competent rates. Mutants lacking the C-terminal redox center, C489S, C490S, and C489S/C490S, are incapable of reducing thioredoxin and can only be reduced to EH2 forms. Additional data suggest that Cys57 attacks Cys490' in the interchange reaction between the N-terminal dithiol and the C-terminal disulfide.