The diagnosis of pediatric-onset inflammatory bowel disease (PIBD) can be challenging in choosing the most informative diagnostic tests and correctly classifying PIBD into its different subtypes. ...Recent advances in our understanding of the natural history and phenotype of PIBD, increasing availability of serological and fecal biomarkers, and the emergence of novel endoscopic and imaging technologies taken together have made the previous Porto criteria for the diagnosis of PIBD obsolete.
We aimed to revise the original Porto criteria using an evidence-based approach and consensus process to yield specific practice recommendations for the diagnosis of PIBD. These revised criteria are based on the Paris classification of PIBD and the original Porto criteria while incorporating novel data, such as for serum and fecal biomarkers. A consensus of at least 80% of participants was achieved for all recommendations and the summary algorithm.
The revised criteria depart from existing criteria by defining 2 categories of ulcerative colitis (UC, typical and atypical); atypical phenotypes of UC should be treated as UC. A novel approach based on multiple criteria for diagnosing IBD-unclassified (IBD-U) is proposed. Specifically, these revised criteria recommend upper gastrointestinal endoscopy and ileocolonscopy for all suspected patients with PIBD, with small bowel imaging (unless typical UC after endoscopy and histology) by magnetic resonance enterography or wireless capsule endoscopy.
These revised Porto criteria for the diagnosis of PIBD have been developed to meet present challenges and developments in PIBD and provide up-to-date guidelines for the definition and diagnosis of the IBD spectrum.
Pyridoxal 5′-phosphate (PLP), the active form of vitamin B6, functions as a cofactor in humans for more than 140 enzymes, many of which are involved in neurotransmitter synthesis and degradation. A ...deficiency of PLP can present, therefore, as seizures and other symptoms that are treatable with PLP and/or pyridoxine. Deficiency of PLP in the brain can be caused by inborn errors affecting B6 vitamer metabolism or by inactivation of PLP, which can occur when compounds accumulate as a result of inborn errors of other pathways or when small molecules are ingested. Whole-exome sequencing of two children from a consanguineous family with pyridoxine-dependent epilepsy revealed a homozygous nonsense mutation in proline synthetase co-transcribed homolog (bacterial), PROSC, which encodes a PLP-binding protein of hitherto unknown function. Subsequent sequencing of 29 unrelated indivduals with pyridoxine-responsive epilepsy identified four additional children with biallelic PROSC mutations. Pre-treatment cerebrospinal fluid samples showed low PLP concentrations and evidence of reduced activity of PLP-dependent enzymes. However, cultured fibroblasts showed excessive PLP accumulation. An E.coli mutant lacking the PROSC homolog (ΔYggS) is pyridoxine sensitive; complementation with human PROSC restored growth whereas hPROSC encoding p.Leu175Pro, p.Arg241Gln, and p.Ser78Ter did not. PLP, a highly reactive aldehyde, poses a problem for cells, which is how to supply enough PLP for apoenzymes while maintaining free PLP concentrations low enough to avoid unwanted reactions with other important cellular nucleophiles. Although the mechanism involved is not fully understood, our studies suggest that PROSC is involved in intracellular homeostatic regulation of PLP, supplying this cofactor to apoenzymes while minimizing any toxic side reactions.
The regulated proliferation and differentiation of neural stem cells before the generation and migration of neurons in the cerebral cortex are central aspects of mammalian development. ...Periventricular neuronal heterotopia, a specific form of mislocalization of cortical neurons, can arise from neuronal progenitors that fail to negotiate aspects of these developmental processes. Here we show that mutations in genes encoding the receptor-ligand cadherin pair DCHS1 and FAT4 lead to a recessive syndrome in humans that includes periventricular neuronal heterotopia. Reducing the expression of Dchs1 or Fat4 within mouse embryonic neuroepithelium increased progenitor cell numbers and reduced their differentiation into neurons, resulting in the heterotopic accumulation of cells below the neuronal layers in the neocortex, reminiscent of the human phenotype. These effects were countered by concurrent knockdown of Yap, a transcriptional effector of the Hippo signaling pathway. These findings implicate Dchs1 and Fat4 upstream of Yap as key regulators of mammalian neurogenesis.
Many plants and animals store toxic or unpalatable compounds in tissues that are easily encountered by predators during attack. Defensive compounds can be produced
de novo
, or obtained from dietary ...sources and stored directly without selection or modification, or can be selectively sequestered or biotransformed. Storage strategies should be optimized to produce effective defence mechanisms but also prevent autotoxicity of the host. Nudibranch molluscs utilize a diverse range of chemical defences, and we investigated the accumulation and distribution of defensive secondary metabolites in body tissues of 19 species of Chromodorididae nudibranchs. We report different patterns of distribution across tissues, where: 1) the mantle had more or different (but structurally related) compounds than the viscera; 2) all compounds in the mantle were also in the viscera; and 3) the mantle had fewer compounds than the viscera. We found no further examples of species that selectively store a single compound, previously reported in
Chromodoris
species. Consistent with other studies, we found high concentrations of metabolites in mantle rim tissues compared to the viscera. Using bioassays, compounds in the mantle were more toxic than compounds found in the viscera for
Glossodoris vespa
Rudman, 1990 and
Ceratosoma brevicaudatum
Abraham, 1876. In
G. vespa
, compounds in the mantle were also more unpalatable to palaemonid shrimp than compounds found in the viscera. This indicates that these species may modify compounds to increase bioactivity for defensive purposes and/or selectively store more toxic compounds. We highlight clear differences in the storage of sequestered chemical defences, which may have important implications for species to employ effective defences against a range of predators.
Craniosynostosis, the premature fusion of the cranial sutures, is a heterogeneous disorder with a prevalence of ∼1 in 2,200 (refs. 1,2). A specific genetic etiology can be identified in ∼21% of ...cases, including mutations of TWIST1, which encodes a class II basic helix-loop-helix (bHLH) transcription factor, and causes Saethre-Chotzen syndrome, typically associated with coronal synostosis. Using exome sequencing, we identified 38 heterozygous TCF12 mutations in 347 samples from unrelated individuals with craniosynostosis. The mutations predominantly occurred in individuals with coronal synostosis and accounted for 32% and 10% of subjects with bilateral and unilateral pathology, respectively. TCF12 encodes one of three class I E proteins that heterodimerize with class II bHLH proteins such as TWIST1. We show that TCF12 and TWIST1 act synergistically in a transactivation assay and that mice doubly heterozygous for loss-of-function mutations in Tcf12 and Twist1 have severe coronal synostosis. Hence, the dosage of TCF12-TWIST1 heterodimers is critical for normal coronal suture development.
Endovascular versus open repair of abdominal aortic aneurysm Greenhalgh, Roger M; Brown, Louise C; Powell, Janet T ...
New England journal of medicine/The New England journal of medicine,
05/2010, Letnik:
362, Številka:
20
Journal Article
Recenzirano
Odprti dostop
Few data are available on the long-term outcome of endovascular repair of abdominal aortic aneurysm as compared with open repair.
From 1999 through 2004 at 37 hospitals in the United Kingdom, we ...randomly assigned 1252 patients with large abdominal aortic aneurysms (> or = 5.5 cm in diameter) to undergo either endovascular or open repair; 626 patients were assigned to each group. Patients were followed for rates of death, graft-related complications, reinterventions, and resource use until the end of 2009. Logistic regression and Cox regression were used to compare outcomes in the two groups.
The 30-day operative mortality was 1.8% in the endovascular-repair group and 4.3% in the open-repair group (adjusted odds ratio for endovascular repair as compared with open repair, 0.39; 95% confidence interval CI, 0.18 to 0.87; P=0.02). The endovascular-repair group had an early benefit with respect to aneurysm-related mortality, but the benefit was lost by the end of the study, at least partially because of fatal endograft ruptures (adjusted hazard ratio, 0.92; 95% CI, 0.57 to 1.49; P=0.73). By the end of follow-up, there was no significant difference between the two groups in the rate of death from any cause (adjusted hazard ratio, 1.03; 95% CI, 0.86 to 1.23; P=0.72). The rates of graft-related complications and reinterventions were higher with endovascular repair, and new complications occurred up to 8 years after randomization, contributing to higher overall costs.
In this large, randomized trial, endovascular repair of abdominal aortic aneurysm was associated with a significantly lower operative mortality than open surgical repair. However, no differences were seen in total mortality or aneurysm-related mortality in the long term. Endovascular repair was associated with increased rates of graft-related complications and reinterventions and was more costly. (Current Controlled Trials number, ISRCTN55703451.)
Bidirectional (anterograde and retrograde) motor-based intraflagellar transport (IFT) governs cargo transport and delivery processes that are essential for primary cilia growth and maintenance and ...for hedgehog signaling functions. The IFT dynein-2 motor complex that regulates ciliary retrograde protein transport contains a heavy chain dynein ATPase/motor subunit, DYNC2H1, along with other less well functionally defined subunits. Deficiency of IFT proteins, including DYNC2H1, underlies a spectrum of skeletal ciliopathies. Here, by using exome sequencing and a targeted next-generation sequencing panel, we identified a total of 11 mutations in WDR34 in 9 families with the clinical diagnosis of Jeune syndrome (asphyxiating thoracic dystrophy). WDR34 encodes a WD40 repeat-containing protein orthologous to Chlamydomonas FAP133, a dynein intermediate chain associated with the retrograde intraflagellar transport motor. Three-dimensional protein modeling suggests that the identified mutations all affect residues critical for WDR34 protein-protein interactions. We find that WDR34 concentrates around the centrioles and basal bodies in mammalian cells, also showing axonemal staining. WDR34 coimmunoprecipitates with the dynein-1 light chain DYNLL1 in vitro, and mining of proteomics data suggests that WDR34 could represent a previously unrecognized link between the cytoplasmic dynein-1 and IFT dynein-2 motors. Together, these data show that WDR34 is critical for ciliary functions essential to normal development and survival, most probably as a previously unrecognized component of the mammalian dynein-IFT machinery.
Outcomes in
-mutant metastatic colorectal cancer (mCRC) remain poor and patients have limited therapeutic options. Adavosertib is the first small-molecule inhibitor of WEE1 kinase. We hypothesized ...that aberrations in DNA replication seen in mCRC with both
and
mutations would sensitize tumors to WEE1 inhibition.
Patients with newly diagnosed mCRC were registered into FOCUS4 and tested for
and
mutations. Those with both mutations who were stable or responding after 16 weeks of chemotherapy were randomly assigned 2:1 between adavosertib and active monitoring (AM). Adavosertib (250 mg or 300 mg) was taken orally once on days 1-5 and days 8-12 of a 3-week cycle. The primary outcome was progression-free survival (PFS), with a target hazard ratio (HR) of 0.5 and 80% power with a one-sided 0.025 significance level.
FOCUS4-C was conducted between April 2017 and Mar 2020 during which time 718 patients were registered; 247 (34%) were
-mutant. Sixty-nine patients were randomly assigned from 25 UK hospitals (adavosertib = 44; AM = 25). Adavosertib was associated with a PFS improvement over AM (median 3.61
1.87 months; HR = 0.35; 95% CI, 0.18 to 0.68;
= .0022). Overall survival (OS) was not improved with adavosertib versus AM (median 14.0
12.8 months; HR = 0.92; 95% CI, 0.44 to 1.94;
= .93). In prespecified subgroup analysis, adavosertib activity was greater in left-sided tumors (HR = 0.24; 95% CI, 0.11 to 0.51), versus right-sided (HR = 1.02; 95% CI, 0.41 to 2.56; interaction
= .043). Adavosertib was well-tolerated; grade 3 toxicities were diarrhea (9%), nausea (5%), and neutropenia (7%).
In this phase II randomized trial, adavosertib improved PFS compared with AM and demonstrates potential as a well-tolerated therapy for
-mutant mCRC. Further testing is required in this sizable population of unmet need.
DNA replication precisely duplicates the genome to ensure stable inheritance of genetic information. Impaired licensing of origins of replication during the G1 phase of the cell cycle has been ...implicated in Meier-Gorlin syndrome (MGS), a disorder defined by the triad of short stature, microtia, and a/hypoplastic patellae. Biallelic partial loss-of-function mutations in multiple components of the pre-replication complex (preRC; ORC1, ORC4, ORC6, CDT1, or CDC6) as well as de novo stabilizing mutations in the licensing inhibitor, GMNN, cause MGS. Here we report the identification of mutations in CDC45 in 15 affected individuals from 12 families with MGS and/or craniosynostosis. CDC45 encodes a component of both the pre-initiation (preIC) and CMG helicase complexes, required for initiation of DNA replication origin firing and ongoing DNA synthesis during S-phase itself, respectively, and hence is functionally distinct from previously identified MGS-associated genes. The phenotypes of affected individuals range from syndromic coronal craniosynostosis to severe growth restriction, fulfilling diagnostic criteria for Meier-Gorlin syndrome. All mutations identified were biallelic and included synonymous mutations altering splicing of physiological CDC45 transcripts, as well as amino acid substitutions expected to result in partial loss of function. Functionally, mutations reduce levels of full-length transcripts and protein in subject cells, consistent with partial loss of CDC45 function and a predicted limited rate of DNA replication and cell proliferation. Our findings therefore implicate the preIC as an additional protein complex involved in the etiology of MGS and connect the core cellular machinery of genome replication with growth, chondrogenesis, and cranial suture homeostasis.
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