Mouse models of NADK2 deficiency analyzed for metabolic and gene expression changes to elucidate pathophysiology.

NADK2 encodes the mitochondrial form of nicotinamide adenine dinucleotide (NAD) kinase, which phosphorylates NAD. Rare recessive mutations in human NADK2 are associated with a syndromic neurological mitochondrial disease that includes metabolic changes, such as hyperlysinemia and 2,4 dienoyl CoA reductase (DECR) deficiency. However, the full pathophysiology resulting from NADK2 deficiency is not known. Here, we describe two chemically induced mouse mutations in Nadk2-S326L and S330P-which cause severe neuromuscular disease and shorten lifespan. The S330P allele was characterized in detail and shown to have marked denervation of neuromuscular junctions by 5 weeks of age and muscle atrophy by 11 weeks of age. Cerebellar Purkinje cells also showed progressive degeneration in this model. Transcriptome profiling on brain and muscle was performed at early and late disease stages. In addition, metabolomic profiling was performed on the brain, muscle, liver and spinal cord at the same ages and on plasma at 5 weeks. Combined transcriptomic and metabolomic analyses identified hyperlysinemia, DECR deficiency and generalized metabolic dysfunction in Nadk2 mutant mice, indicating relevance to the human disease. We compared findings from the Nadk model to equivalent RNA sequencing and metabolomic datasets from a mouse model of infantile neuroaxonal dystrophy, caused by recessive mutations in Pla2g6. This enabled us to identify disrupted biological processes that are common between these mouse models of neurological disease, as well as those processes that are gene-specific. These findings improve our understanding of the pathophysiology of neuromuscular diseases and describe mouse models that will be useful for future preclinical studies.

Baseline characteristics and comorbidities in the CAnadian REgistry for Pulmonary Fibrosis.

BACKGROUND: The CAnadian REgistry for Pulmonary Fibrosis (CARE-PF) is a multi-center, prospective registry designed to study the natural history of fibrotic interstitial lung disease (ILD) in adults. The aim of this cross-sectional sub-study was to describe the baseline characteristics, risk factors, and comorbidities of patients enrolled in CARE-PF to date. METHODS: Patients completed study questionnaires and clinical measurements at enrollment and each follow-up visit. Environmental exposures were assessed by patient self-report and comorbidities by the Charlson Comorbidity Index (CCI). Baseline characteristics, exposures, and comorbidities were described for the overall study population and for incident cases, and were compared across ILD subtypes. RESULTS: The full cohort included 1285 patients with ILD (961 incident cases (74.8%)). Diagnoses included connective tissue disease-associated ILD (33.3%), idiopathic pulmonary fibrosis (IPF) (24.7%), unclassifiable ILD (22.3%), chronic hypersensitivity pneumonitis (HP) (7.5%), sarcoidosis (3.2%), non-IPF idiopathic interstitial pneumonias (3.0%, including idiopathic nonspecific interstitial pneumonia (NSIP) in 0.9%), and other ILDs (6.0%). Patient-reported exposures were most frequent amongst chronic HP, but common across all ILD subtypes. The CCI was ≤2 in 81% of patients, with a narrow distribution and range of values. CONCLUSIONS: CTD-ILD, IPF, and unclassifiable ILD made up 80% of ILD diagnoses at ILD referral centers in Canada, while idiopathic NSIP was rare when adhering to recommended diagnostic criteria. CCI had a very narrow distribution across our cohort suggesting it may be a poor discriminator in assessing the impact of comorbidities on patients with ILD.

Modification of the sterol profile in milk through feeding.

The fortification of milk with phytosterols is an increasingly common practice to enhance the sterol profile and offer consumers potential health benefits. This study investigated whether cattle feed can influence the profile of phytosterols and cholesterol in the milk produced as an alternative to direct fortification of milk. Five experiments were performed using feeds commonly used by Australian dairy farmers and selected formulated rumen-protected feeds. Statistical significances were observed for some individual plant sterols and cholesterol in milk under these differing feeding regimens compared with the respective controls. In the case of the phytosterols, where the daily recommended consumption is typically 2 g per day, the total phytosterols were <0.12 mg/100 mL of milk. An experiment using a rumen-protected feed with high phytosterol levels suggested a decreased transfer of cholesterol to the milk by as much as 20%, although further work is required to confirm these preliminary results. Overall, the study suggests that different feeding practices have minimal effect on the resulting sterol profile of the milk.

Instability of pulses in gradient reaction-diffusion systems: a symplectic approach.

In a scalar reaction-diffusion equation, it is known that the stability of a steady state can be determined from the Maslov index, a topological invariant that counts the state's critical points. In particular, this implies that pulse solutions are unstable. We extend this picture to pulses in reaction-diffusion systems with gradient nonlinearity. In particular, we associate a Maslov index to any asymptotically constant state, generalizing existing definitions of the Maslov index for homoclinic orbits. It is shown that this index equals the number of unstable eigenvalues for the linearized evolution equation. Finally, we use a symmetry argument to show that any pulse solution must have non-zero Maslov index, and hence be unstable.This article is part of the theme issue 'Stability of nonlinear waves and patterns and related topics'.

Successful pregnancy and breastfeeding in a woman with mucopolysaccharidosis type I while receiving laronidase enzyme replacement. therapy.

The authors describe the first mother-infant pair to complete an on-going, prospective, open-label, Phase 4 trial (ALIU) UU3, NCT00418821) determining the safety of laronidase enzyme replacement therapy (ERT) in pregnant women with mucopolysaccharidosis type I (MPS I) and their breastfed infants. The mother, a 32-year-old with attenuated MPS I (Scheie syndrome), received laronidase for three years and continued treatment throughout her second pregnancy and while lactating. A healthy 2.5 kg male was delivered by elective cesarean section at 37 weeks. He was breastfed for three months. No laronidase was detected in breast milk. The infant never developed anti-laronidase IgM antibodies, never had inhibitory antibody activity in a cellular uptake assay, and always had normal urinary glycosaminoglycan (GAG) levels. No drug-related adverse events were reported. At 2.5 years of age, the boy is healthy with normal growth and development. In this first prospectively monitored mother-infant pair, laronidase during pregnancy and breastfeeding was uneventful.

An objective approach to model reduction: Application to the Sirius wheat model.

An existing simulation model of wheat growth and development, Sirius, was evaluated through a systematic model reduction procedure. The model was automatically manipulated under software control to replace variables within the model structure with constants, individually and in combination. Predictions of the resultant models were compared to growth analysis observations of total biomass, grain yield, and canopy leaf area derived from 9 trials conducted in the UK and New Zealand under optimal, nitrogen limiting and drought conditions. Model performance in predicting these observations was compared in order to evaluate whether individual model variables contributed positively to the overall prediction. Of the 1 1 1 model variables considered 16 were identified as potentially redundant. Areas of the model where there was evidence of redundancy were: (a) translocation of biomass carbon to grain; (b) nitrogen physiology; (c) adjustment of air temperature for various modelled processes; (d) allowance for diurnal variation in temperature; (e) vernalisation (f) soil nitrogen mineralisation (g) soil surface evaporation. It is not suggested that these are not important processes in real crops, rather, that their representation in the model cannot be justified in the context of the analysis. The approach described is analogous to a detailed model inter-comparison although it would be better described as a model intra-comparison as it is based on the comparison of many simplified forms of the same model. The approach provides automation to increase the efficiency of the evaluation and a systematic means of increasing the rigour of the evaluation.

Machine learning modeling to predict causes of infectious abortions and perinatal mortalities in cattle.

A plethora of infectious and non-infectious causes of bovine abortions and perinatal mortalities (APM) have been reported in literature. However, due to financial limitations or a potential zoonotic impact, many laboratories only offer a standard analytical panel, limited to a preestablished number of pathogens. To improve the cost-efficiency of laboratory diagnostics, it could be beneficial to design a targeted analytical approach for APM cases, based on maternal and environmental characteristics associated with the prevalence of specific abortifacient pathogens. The objective of this retrospective observational study was to implement a machine learning pipeline (MLP) to predict maternal and environmental factors associated with infectious APM. Our MLP based on a greedy ensemble approach incorporated a standard tuning grid of four models, applied on a dataset of 1590 APM cases with a positive diagnosis that was achieved by analyzing an extensive set of abortifacient pathogens. Production type (dairy/beef), gestation length, and season were successfully predicted by the greedy ensemble, with a modest prediction capacity which ranged between 63 and 73 %. Besides the predictive accuracy of individual variables, our MLP hierarchically identified predictor importance causes of associated environmental/maternal characteristics of APM. For instance, in APM cases that happened in beef cows, season at APM (spring/summer) was the most important predictor with a relative importance of 24 %. Furthermore, at the last trimester of gestation Trueperella pyogenes and Neospora caninum were the most important predictors of APM with a relative importance of 22 and 17 %, respectively. Interestingly, herd size came out as the most relevant predictor for APM in multiparous dams, with a relative importance of 12 %. Based on these and other mix of predicted environmental/maternal and pathogenic potential causes, it could be concluded that implementing our MLP may be beneficial to design a more cost-effective, case-specific diagnostic approach for bovine APM cases at the diagnostic laboratory level.

Dp71 can restore the dystrophin-associated glycoprotein complex in muscle but fails to prevent dystrophy.

Two lines of transgenic mdx mice have been generated that express a 71 kD non-muscle isoform of dystrophin (Dp71) in skeletal muscle. This isoform contains the cysteine-rich and C-terminal domains of dystrophin, but lacks the N-terminal actin-binding and central spectrin-like repeat domains. Dp71 was associated with the sarcolemma membrane, where it restored normal expression and localization of all members of the dystrophin-associated glycoprotein complex. However, the skeletal muscle pathology of the transgenic mdx mice remained severe. These results indicate that the dystrophin C terminus cannot function independently to prevent dystrophic symptoms and confirms predictions based on patient data that both the N and C-terminal domains are required for normal dystrophin function.

New mdx mutation disrupts expression of muscle and nonmuscle isoforms of dystrophin.

The dystrophin gene encodes several tissue-specific protein isoforms that are generated by alternative splicing and by transcription from at least three separate promoters. We have characterized the mutation in a new strain of mdx mice that results in aberrant splicing of both the 14 and 4.8 kilobase dystrophin mRNAs and disrupts expression of the muscle and brain 427K and nonmuscle 70K isoforms of dystrophin. In contrast, we have determined that expression of the 70K isoform is normal in the original mdx mutant. We have cloned the unique 5' exon of the murine 4.8 kb mRNA and have analysed the tissue distribution and aberrant splicing of this transcript in the mdx3Cv mutant. This new mdx mutant will provide an improved model system for functional studies of the dystrophin C-terminus in muscle and nonmuscle tissues.

The mouse fidgetin gene defines a new role for AAA family proteins in mammalian development.

The mouse mutation fidget arose spontaneously in a heterogeneous albino stock. This mutant mouse is characterized by a side-to-side head-shaking and circling behaviour, due to reduced or absent semicircular canals. Fidget mice also have small eyes, associated with cell-cycle delay and insufficient growth of the retinal neural epithelium, and lower penetrance skeletal abnormalities, including pelvic girdle dysgenesis, skull bone fusions and polydactyly. By positional cloning, we found the gene mutated in fidget mice, fidgetin (Fign), which encodes a new member of the 'meiotic' or subfamily-7 (SF7; ref. 7) group of ATPases associated with diverse cellular activities (AAA proteins). We also discovered two closely related mammalian genes. AAA proteins are molecular chaperones that facilitate a variety of functions, including membrane fusion, proteolysis, peroxisome biogenesis, endosome sorting and meiotic spindle formation, but functions for the SF7 AAA proteins are largely unknown. Fidgetin is the first mutant AAA protein found in a mammalian developmental mutant, thus defining a new role for these proteins in embryonic development.

Ethylene in organic synthesis. Repetitive hydrovinylation of alkenes for highly enantioselective syntheses of pseudopterosins.

In this report we highlight the significant potential of ethylene as a reagent for the introduction of a vinyl group with excellent stereoselectivity at three different stages in the synthesis of a broad class of natural products, best exemplified by syntheses of pseudopterosins. The late-stage applications of the asymmetric hydrovinylation reaction further illustrate the compatibility of the catalyst with complex functional groups. We also show that, depending on the choice of the catalyst, it is possible to either enhance or even completely reverse the inherent diastereoselectivity in the reactions of advanced chiral intermediates. This should enable the synthesis of diastereomeric analogs of several classes of medicinally relevant compounds that are not readily accessible by the existing methods, which depend on 'substrate control' for the installation of many of the chiral centers, especially in molecules of this class.

A realist evaluation of a collaborative model to support research co-production in long-term care settings in England: the ExCHANGE protocol.

BACKGROUND: Collaborative working between academic institutions and those who provide health and social care has been identified as integral in order to produce acceptable, relevant, and timely research, and for outputs to be useful and practical to implement. The ExCHANGE Collaboration aims to bring together researchers and people working, living in and visiting care homes to build capacity, share and mobilise knowledge, and identify key areas for future research. This paper describes an embedded, formative, realist and theory-driven evaluation which aims to gather information about how successful the ExCHANGE Collaboration is perceived to be in achieving its aims. An existing realist programme theory from the literature - Closer Collaboration - will be supplemented by two substantive theories: Co-production and Knowledge Brokering. This will result in an initial programme theory which will be tested by this formative evaluation to refine understanding of how the ExCHANGE Collaboration works. METHODS: The evaluation will employ mixed qualitative methods, including: analysis of documents such as feedback forms, Knowledge Broker journal/diary, event attendance records, risk and issues logs and other relevant paperwork gathered as part of project delivery; observations of events/activities; and interviews with care home providers and staff, care home residents, residents' family members, and researchers who are involved in the project (both project design/delivery, and also attendance or involvement in project activities/events). Framework Analysis will be used to interpret the data collected; analysis will be strategic, by focusing on particular key areas of importance in the developing theory of how the ExCHANGE Collaboration might achieve change. RESULTS: The results of this study are expected to be published in 2022. DISCUSSION: This evaluation will investigate how successful the ExCHANGE Collaboration is perceived to be in achieving its aims, in what way, in which contexts, and how this may differ for those involved. It will do this by testing an initial programme theory about how the collaboration works, for whom, under which circumstances, and in what way. Findings will be shared through written publication, an end of project learning event for those involved/interested in the project, and a lay summary to be made publically available.

The phase diagram of Ti-6Al-4V at high-pressures and high-temperatures.

We report results from a series of diamond-anvil-cell synchrotron x-ray diffraction and large-volume-press experiments, and calculations, to investigate the phase diagram of commercial polycrystalline high-strength Ti-6Al-4V alloy in pressure-temperature space. Up to ∼30 GPa and 886 K, Ti-6Al-4V is found to be stable in the hexagonal-close-packed, orαphase. The effect of temperature on the volume expansion and compressibility ofα-Ti-6Al-4V is modest. The martensiticα→ω(hexagonal) transition occurs at ∼30 GPa, with both phases coexisting until at ∼38-40 GPa the transition to theωphase is completed. Between 300 K and 844 K theα→ωtransition appears to be independent of temperature.ω-Ti-6Al-4V is stable to ∼91 GPa and 844 K, the highest combined pressure and temperature reached in these experiments. Pressure-volume-temperature equations-of-state for theαandωphases of Ti-6Al-4V are generated and found to be similar to pure Ti. A pronounced hysteresis is observed in theω-Ti-6Al-4V on decompression, with the hexagonal structure reverting back to theαphase at pressures below ∼9 GPa at room temperature, and at a higher pressure at elevated temperatures. Based on our data, we estimate the Ti-6Al-4Vα-ß-ωtriple point to occur at ∼900 K and 30 GPa, in good agreement with our calculations.

A hypoxia-responsive element mediates a novel pathway of activation of the inducible nitric oxide synthase promoter.

Picolinic acid, a catabolite of L-tryptophan, activates the transcription of the inducible nitric oxide synthase gene (iNOS) in IFN-gamma-treated murine macrophages. We performed functional studies on the 5' flanking region of the iNOS gene linked to a CAT reporter gene to identify the cis-acting element(s) responsible for the activation of iNOS transcription by picolinic acid. Transient transfection assays showed that the full-length iNOS promoter in the murine macrophage cell line ANA-1 was activated by the synergistic interaction between IFN-gamma and picolinic acid. Deletion or mutation of the iNOS promoter region from -227 to -209, containing a sequence homology to a hypoxia-responsive enhancer (iNOS-HRE), decreased picolinic acid- but not LPS-induced CAT activity by more than 70%. Functional studies using a tk promoter-CAT reporter gene plasmid demonstrated that the iNOS-HRE was sufficient to confer inducibility by picolinic acid but not by IFN-gamma or LPS. Electrophoretic mobility shift assays confirmed that picolinic acid alone induced a specific binding activity to the iNOS-HRE. Furthermore, we found that the iNOS-HRE activity was inducible by hypoxia and that hypoxia in combination with IFN-gamma activated the iNOS promoter in transient transfection assays and induced iNOS transcription and mRNA expression. These data establish that the iNOS-HRE is a novel regulatory element of the iNOS promoter activity in murine macrophages and provide the first evidence that iNOS is a hypoxia-inducible gene.

20p12.3 microdeletion predisposes to Wolff-Parkinson-White syndrome with variable neurocognitive deficits.

BACKGROUND: Wolff-Parkinson-White syndrome (WPW) is a bypass re-entrant tachycardia that results from an abnormal connection between the atria and ventricles. Mutations in PRKAG2 have been described in patients with familial WPW syndrome and hypertrophic cardiomyopathy. Based on the role of bone morphogenetic protein (BMP) signalling in the development of annulus fibrosus in mice, it has been proposed that BMP signalling through the type 1a receptor and other downstream components may play a role in pre-excitation. METHODS AND RESULTS: Using the array comparative genomic hybridisation (CGH), we identified five individuals with non-recurrent deletions of 20p12.3. Four of these individuals had WPW syndrome with variable dysmorphisms and neurocognitive delay. With the exception of one maternally inherited deletion, all occurred de novo, and the smallest of these harboured a single gene, BMP2. In two individuals with additional features of Alagille syndrome, deletion of both JAG1 and BMP2 were identified. Deletion of this region has not been described as a copy number variant in the Database of Genomic Variants and has not been identified in 13 321 individuals from other cohort examined by array CGH in our laboratory. CONCLUSIONS: Our findings demonstrate a novel genomic disorder characterised by deletion of BMP2 with variable cognitive deficits and dysmorphic features and show that individuals bearing microdeletions in 20p12.3 often present with WPW syndrome.

Microdeletion/duplication at 15q13.2q13.3 among individuals with features of autism and other neuropsychiatric disorders.

BACKGROUND: Segmental duplications at breakpoints (BP4-BP5) of chromosome 15q13.2q13.3 mediate a recurrent genomic imbalance syndrome associated with mental retardation, epilepsy, and/or electroencephalogram (EEG) abnormalities. PATIENTS: DNA samples from 1445 unrelated patients submitted consecutively for clinical array comparative genomic hybridisation (CGH) testing at Children's Hospital Boston and DNA samples from 1441 individuals with autism from 751 families in the Autism Genetic Resource Exchange (AGRE) repository. RESULTS: We report the clinical features of five patients with a BP4-BP5 deletion, three with a BP4-BP5 duplication, and two with an overlapping but smaller duplication identified by whole genome high resolution oligonucleotide array CGH. These BP4-BP5 deletion cases exhibit minor dysmorphic features, significant expressive language deficits, and a spectrum of neuropsychiatric impairments that include autism spectrum disorder, attention deficit hyperactivity disorder, anxiety disorder, and mood disorder. Cognitive impairment varied from moderate mental retardation to normal IQ with learning disability. BP4-BP5 covers approximately 1.5 Mb (chr15:28.719-30.298 Mb) and includes six reference genes and 1 miRNA gene, while the smaller duplications cover approximately 500 kb (chr15:28.902-29.404 Mb) and contain three reference genes and one miRNA gene. The BP4-BP5 deletion and duplication events span CHRNA7, a candidate gene for seizures. However, none of these individuals reported here have epilepsy, although two have an abnormal EEG. CONCLUSIONS: The phenotype of chromosome 15q13.2q13.3 BP4-BP5 microdeletion/duplication syndrome may include features of autism spectrum disorder, a variety of neuropsychiatric disorders, and cognitive impairment. Recognition of this broader phenotype has implications for clinical diagnostic testing and efforts to understand the underlying aetiology of this syndrome.

Influence of chronic dietary carbohydrate supplementation on plasma cytokine responses to exercise.

This study examined the influence of 28 days of dietary carbohydrate (CHO) supplementation on plasma cytokine responses to cycle ergometry. Sixteen highly trained male cyclists and triathletes (age: 30.6+/-5.6 y; VO2max: 64.8+/-4.7 mL x kg(-1) x min(-1); mean+/-SD) participated in the study. One group (n=8) consumed a higher-CHO (8.5+/-1.7 g x kg(-1) body mass.day (-1)) diet for 28 days; a second group (n=8) consumed a moderate-CHO diet (5.3+/-0.4 g x kg (-1) x day (-1)). Total daily energy intakes were similar between the two groups. Cytokine responses to cycle ergometry were assessed prior to and again following the dietary intervention period. The cycle ergometry protocol involved 100 min steady state cycling at 70% VO2max followed by a time trial of approximately 30 min. Athletes were provided with 15 mL x kg (-1) x h (-1) of water during each trial. Blood samples were collected pre-, immediately post- and 1 h post-exercise for determination of plasma glucose and pro-inflammatory (IL-6, IL-8) and anti-inflammatory (IL-10, IL-1ra) cytokine concentrations. Cytokine responses to cycle ergometry were not substantially altered following the 28-day higher-CHO diet. In contrast, following the 28-day moderate-CHO diet, there were approximately 30-50% reductions (p=0.08-0.11) in anti-inflammatory cytokine responses post-exercise. These findings suggest that increased dietary CHO content alone does not effectively attenuate the pro-inflammatory cytokine response to exercise, however, there may be a small reduction in the anti-inflammatory cytokine response.

A precursor of cytoplasmic actin in cultured Drosophila cells.

In continuous lines of cultured Drosophila cells two forms of cytoplasmic actin, designated II and III, are detected after a 25- to 120-min pulse label with [35S]methionine. However, only one of these, actin II, accumulates in the cell. With the use of a pulse-chase protocol and two-dimensional gel electrophoresis, it has been found that actin III is synthesized as a precursor of the more stable cytoplasmic actin II. The half-life of actin III was estimated to be approximately 50 min.

Cuticle of Caenorhabditis elegans: its isolation and partial characterization.

The adult cuticle of the soil nematode, Caenorhabditis elegans, is a proteinaceous extracellular structure elaborated by the underlying layer of hypodermal cells during the final molt in the animal's life cycle. The cuticle is composed of an outer cortical layer connected by regularly arranged struts to an inner basal layer. The cuticle can be isolated largely intact and free of all cellular material by sonication and treatment with 1% sodium dodecyl sulfate (SDS). Purified cuticles exhibit a negative material in the basal cuticle layer. The cuticle layers differ in their solubility in sulfhydryl reducing agents, susceptibility to various proteolytic enzymes and amino acid composition. The struts, basal layer, and internal cortical layer are composed of collagen proteins that are extensively cross-linked by disulfide bonds. The external cortical layer appears to contain primarily noncollagen proteins that are extensively cross-linked by nonreducible covalent bonds. The collagen proteins extracted from the cuticle with a reducing agent can be separated by SDS-polyacrylamide gel electrophoresis into eight major species differing in apparent molecular weight.

Zeugmatin: a new high molecular weight protein associated with Z lines in adult and early embryonic striated muscle.

Monoclonal antibodies were generated to a purified preparation of the fascia adherens domains of the intercalated discs of chicken cardiac cell membranes. One of these antibodies, McAb 20, immunofluorescently labeled the Z lines of adult skeletal muscle, the Z lines and intercalated discs of adult cardiac muscle, and the dense bodies and dense plaques of adult gizzard smooth muscle. In addition, McAb 20 was found to label regenerating muscle cells in a cross-striated pattern much like that of Z lines in 24-h muscle cell cultures before the appearance of Z lines was detectable by phase or Nomarski optics and before the concentration of alpha-actinin occurred at the Z lines. Thus, McAb 20 appears to be directed against an antigen involved in early myofibrillar organization. Preliminary biochemical characterization of the antigen recognized by McAb 20 indicates that it is a high molecular weight doublet of over 5 X 10(5) kD that is highly susceptible to proteolysis. By virtue of its presence in Z lines, and its possible role in the end-on attachment of microfilaments to Z lines and membranes, we have named this protein zeugmatin (xi epsilon nu gamma mu alpha identical to yoking).