Skeletal Malformations Research Articles

Sirtuin 6 in preosteoclasts suppresses age- and estrogen deficiency-related bone loss by stabilizing estrogen receptor α.

Emerging evidence indicates that estrogen receptor (ER) α is an important modulator of bone homeostasis, which occurs partly by promoting osteoclast apoptosis. Sirtuin 6 (Sirt6) is an anti-aging molecule, and its deficiency in mice results in skeletal malformations associated with progeroid features. However, the effects of Sirt6 on ERα function in osteoclasts, and thus on aging- or estrogen deficiency-induced bone loss, have not been studied. Here, we show that myeloid-specific deletion of Sirt6 led to decreased ERα protein level and apoptotic cell death in preosteoclasts. Consequently, myeloid Sirt6 KO mice showed aggravated cancellous bone loss both with aging and following an ovariectomy compared to wild-type littermates. In contrast, Sirt6 transgenic mice were protected from ovariectomy-induced bone loss. Mechanistically, Sirt6 deacetylated ERα protein to prevent its proteasomal degradation, in which lysine 171 and lysine 299 were critical residues. Sirt6-mediated ERα stabilization promoted transcription of Fas ligand in preosteoclasts, resulting in apoptosis of osteoclasts. Finally, the level of Sirt6 in human preosteoclasts was correlated positively with bone density and ERα but negatively with age. In conclusion, our results suggest that deacetylation and upregulation of ERα by Sirt6 in preosteoclasts prevent bone loss by inhibiting osteoclast-mediated bone resorption. Activation of Sirt6 in preosteoclasts may provide a new therapeutic approach to attenuate osteoporosis in older or postmenopausal patients.

Chromosome alignment maintenance requires the MAP RECQL4, mutated in the Rothmund-Thomson syndrome.

RecQ-like helicase 4 (RECQL4) is mutated in patients suffering from the Rothmund-Thomson syndrome, a genetic disease characterized by premature aging, skeletal malformations, and high cancer susceptibility. Known roles of RECQL4 in DNA replication and repair provide a possible explanation of chromosome instability observed in patient cells. Here, we demonstrate that RECQL4 is a microtubule-associated protein (MAP) localizing to the mitotic spindle. RECQL4 depletion in M-phase-arrested frog egg extracts does not affect spindle assembly per se, but interferes with maintaining chromosome alignment at the metaphase plate. Low doses of nocodazole depolymerize RECQL4-depleted spindles more easily, suggesting abnormal microtubule-kinetochore interaction. Surprisingly, inter-kinetochore distance of sister chromatids is larger in depleted extracts and patient fibroblasts. Consistent with a role to maintain stable chromosome alignment, RECQL4 down-regulation in HeLa cells causes chromosome misalignment and delays mitotic progression. Importantly, these chromosome alignment defects are independent from RECQL4's reported roles in DNA replication and damage repair. Our data elucidate a novel function of RECQL4 in mitosis, and defects in mitotic chromosome alignment might be a contributing factor for the Rothmund-Thomson syndrome.

Failing to Make Ends Meet: The Broad Clinical Spectrum of DNA Ligase IV Deficiency. Case Series and Review of the Literature.

DNA repair defects are inborn errors of immunity that result in increased apoptosis and oncogenesis. DNA Ligase 4-deficient patients suffer from a wide range of clinical manifestations since early in life, including: microcephaly, dysmorphic facial features, growth failure, developmental delay, mental retardation; hip dysplasia, and other skeletal malformations; as well as a severe combined immunodeficiency, radiosensitivity, and progressive bone marrow failure; or, they may present later in life with hematological neoplasias that respond catastrophically to chemo- and radiotherapy; or, they could be asymptomatic. We describe the clinical, laboratory, and genetic features of five Mexican patients with LIG4 deficiency, together with a review of 36 other patients available in PubMed Medline. Four out of five of our patients are dead from lymphoma or bone marrow failure, with severe infection and massive bleeding; the fifth patient is asymptomatic despite a persistent CD4+ lymphopenia. Most patients reported in the literature are microcephalic females with growth failure, sinopulmonary infections, hypogammaglobulinemia, very low B-cells, and radiosensitivity; while bone marrow failure and malignancy may develop at a later age. Dysmorphic facial features, congenital hip dysplasia, chronic liver disease, gradual pancytopenia, lymphoma or leukemia, thrombocytopenia, and gastrointestinal bleeding have been reported as well. Most mutations are compound heterozygous, and all of them are hypomorphic, with two common truncating mutations accounting for the majority of patients. Stem-cell transplantation after reduced intensity conditioning regimes may be curative.

Impact of Le-Fort I osteotomy on anatomical and functional aspects of the nasal airway and on quality of life.

Orthognathic surgery is a well-established procedure for skeletal deformities. Beneficial influences to the posterior airway space (PAS) have been described, but little is known about the subjective aesthetical and functional nasal aspects after orthognathic surgery. The aim of this study was to evaluate nasal airflow by anterior rhinomanometry and volumetric changes in the nasal airway space after mono- or bimaxillary surgery using cone-beam computed tomography (CBCT) and a new segmentation software. Furthermore, changes of patient's quality of life (QoL) should be assessed. Ten patients (9 skeletal class malformation III, 1 skeletal class malformation I) were included. CBCT images, rhinological inspections and anterior rhinomanometries were performed before (T0) and after surgery (T1). All patients completed the FROI-17, the ROE and the SF-36 questionnaires. A significant postoperative gain for nasal airway volume compared with the baseline was shown (p < 0.014). No statistically significant differences between pre- and postoperative flow rates were found (p = 0.114). Pre- and postoperative cohorts did not differ in responses of disease-specific (ROE and FROI-17) and generic QoL questionnaires (SF-36). Maxillary relocation surgery leads to a significant increase in nasal airway space. Subjectively, orthognathic patients did not experience any functional but psychosocial aspects after bimaxillary surgery.

The effect of Cynara scolymus (artichoke) on maternal reproductive outcomes and fetal development in rats

Cynara scolymus (C.scolymus) is a plant employed worldwide as an herbal medicine. However, there is a paucity of data related to the evaluation of its toxicity in commercial preparations; thus, the aim of this study was to evaluate the possible teratogenic effect of the dry extract of C.scolymus leaves in Wistar rats. Females were treated, from gestation day (GD) 6 until GD19, with 0.0, 1.0, 2.0 or 4.0 g/kg body weight of C.scolymus extract. At GD20, a cesarean section was performed for evaluation of maternal and fetal parameters. C.scolymus did not induce changes in food consumption, preimplantation or postimplantation losses, placental weight or biochemical profile. An increase in water consumption was observed in pregnant females treated with the higher doses of C.scolymus. Experimental groups showed lower body weight gain during pregnancy and lower gravid uterus weight. Maternal body weight minus the gravid uterus weight did not result in significant differences. Reductions in fetal weight and length were observed in experimental groups. The number of live pups per litter was lower in the highest dose group. No fetal skeletal or visceral malformations were detected. The results showed that the consumption of artichoke during pregnancy clearly has a negative impact on fetuses.

Genotoxic and Teratogenic Effects of Mycophenolate Mofetil in Mice

Mycophenolate mofetil (MMF) or cellcept is an immunosuppressive drug which used to suppress immune system activity and reduce the risk of organ rejection in transplant patients. The present study investigates the cytotoxic, genotoxic and teratogenic potential of MMF in white mice. Genotoxic effects of this agent were evaluated using micronucleus test, and skeletal malformations were investigated according to dose concentration as treatment was with 16.6 mg. kg−1 and 33.3 mg. kg−1 MMF. A significant difference was observed in MNiPCEs in both treated groups than negative control, and 33.3 mg. kg−1 concentration showed significant differences in MNi than negative control. A significant malformation was found in abnormal bones of cranial, ribs, pelvic girdle and shoulder girdle bones in 16.6 mg. kg−1 cellcept group, while there were no significant differences in bone total number. There was a high difference in bones total number of thoracic and neck vertebrae of 33.3 mg. kg−1 treatment, while a high significant show in abnormal bones of thoracic, neck, tail, sacral and lumbar vertebrae in 16.6 mg. kg−1 group. In conclusion, MMF has cytotoxicity and/or genotoxicity action it possesses a high teratogenic potential, these effects increase with increasing dose.

Duplicación digestiva múltiple: estómago y duodeno con tejido pancreático ectópico

Intestinal duplications are congenital anomalies representing cystic or tubular lesions that can be found in any segment of the digestive tract. They are in the mesenteric border of the compromised segment with which they share irrigation. They are of rare occurrence and of multiple embryological etiology. The three essential factors for diagnosis include being surrounded by smooth muscle, sharing a common wall, and having mucous from the place of origin. Multiple duplications occur in 15% of duplications and are frequently associated with skeletal, digestive, and genitourinary tract malformations. We present the case of a pediatric patient with a rare multiple duplication of the digestive tract that includes gastric and duodenal duplication with pancreatic ectopic tissue, which represented a challenge for diagnosis and therapeutic management.

Fibroblast growth factors in skeletal development.

Fibroblast growth factors (FGFs) and their receptors (FGFRs) are expressed throughout all stages of skeletal development. In the limb bud and in cranial mesenchyme, FGF signaling is important for formation of mesenchymal condensations that give rise to bone. Once skeletal elements are initiated and patterned, FGFs regulate both endochondral and intramembranous ossification programs. In this chapter, we review functions of the FGF signaling pathway during these critical stages of skeletogenesis, and explore skeletal malformations in humans that are caused by mutations in FGF signaling molecules.

Roles and regulation of SOX transcription factors in skeletogenesis.

SOX transcription factors participate in the specification, differentiation and activities of many cell types in development and beyond. The 20 mammalian family members are distributed into eight groups based on sequence identity, and while co-expressed same-group proteins often have redundant functions, different-group proteins typically have distinct functions. More than a handful of SOX proteins have pivotal roles in skeletogenesis. Heterozygous mutations in their genes cause human diseases, in which skeletal dysmorphism is a major feature, such as campomelic dysplasia (SOX9), or a minor feature, such as LAMSHF syndrome (SOX5) and Coffin-Siris-like syndromes (SOX4 and SOX11). Loss- and gain-of-function experiments in animal models have revealed that SOX4 and SOX11 (SOXC group) promote skeletal progenitor survival and control skeleton patterning and growth; SOX8 (SOXE group) delays the differentiation of osteoblast progenitors; SOX9 (SOXE group) is essential for chondrocyte fate maintenance and differentiation, and works in cooperation with SOX5 and SOX6 (SOXD group) and other types of transcription factors. These and other SOX proteins have also been proposed, mainly through in vitro experiments, to have key roles in other aspects of skeletogenesis, such as SOX2 in osteoblast stem cell self-renewal. We here review current knowledge of well-established and proposed skeletogenic roles of SOX proteins, their transcriptional and non-transcriptional actions, and their modes of regulation at the gene, RNA and protein levels. We also discuss gaps in knowledge and directions for future research to further decipher mechanisms underlying skeletogenesis in health and diseases and identify treatment options for skeletal malformation and degeneration diseases.

Development of the axial skeleton and intervertebral disc.

Development of the axial skeleton is a complex, stepwise process that relies on intricate signaling and coordinated cellular differentiation. Disruptions to this process can result in a myriad of skeletal malformations that range in severity. The notochord and the sclerotome are embryonic tissues that give rise to the major components of the intervertebral discs and the vertebral bodies of the spinal column. Through a number of mouse models and characterization of congenital abnormalities in human patients, various growth factors, transcription factors, and other signaling proteins have been demonstrated to have critical roles in the development of the axial skeleton. Balance between opposing growth factors as well as other environmental cues allows for cell fate specification and divergence of tissue types during development. Furthermore, characterization of progenitor cells for specific cell lineages has furthered the understanding of specific spatiotemporal cues that cells need in order to initiate and complete development of distinct tissues. Identifying specific marker genes that can distinguish between the various embryonic and mature cell types is also of importance. Clinically, understanding developmental clues can aid in the generation of therapeutics for musculoskeletal disease through the process of developmental engineering. Studies into potential stem cell therapies are based on knowledge of the normal processes that occur in the embryo, which can then be applied to stepwise tissue engineering strategies.

Microdeleción 1q21.1 y psicosis. A próposito de un caso

La microdeleción 1q21.1 no constituye por sí misma un síndrome clínico reconocible, ya que algunas personas con la deleción no presentan hallazgos clínicos y otras tienen repercusiones variables. Sin embargo, se han descrito alteraciones relacionadas con la ausencia de los genes localizados en dicho fragmento. Entre estas características se incluyen microcefalia, rasgos faciales dismórficos, alteraciones oculares, defectos cardíacos, anomalías genitourinarias, malformaciones esqueléticas, convulsiones, retraso en el neurodesarrollo, dificultades en el aprendizaje y discapacidad intelectual leve. En cuanto a patologías psiquiátricas, hay mayor incidencia de trastornos del espectro autista, trastorno por déficit de atención con hiperactividad, trastornos de ansiedad y del estado de ánimo, trastornos del sueño y esquizofrenia. Presentamos el caso clínico de una paciente portadora de microdeleción 1q21.1 hospitalizada en una Unidad de Psiquiatría del Niño y el Adolescente por sintomatología delirante y alucinaciones.

Sub-lethal effects of waterborne copper in early developmental stages of rainbow trout (Oncorhynchus mykiss)

The aim of this work was to study the impact of copper during a sub-chronic exposure to environmental concentrations in the early life stages of rainbow trout (Oncorhynchus mykiss). Eyed-stage embryos of rainbow trout, at 265 °D, were exposed in semi-static conditions to sub-lethal concentrations of CuSO4 up to the larval stage (528 °D) under laboratory-controlled conditions. During 3 weeks, they were exposed to the environmentally-realistic concentration of 2 µg/L Cu and to a 10-fold higher concentration, 20 µg/L Cu. Several biological (survival, hatching success, malformation, growth) and behavioral (swimming activity) and molecular endpoints (genotoxicity and gene transcription) were studied. Exposure to 20 µg/L Cu had an inhibitory effect on hatching and increased half-hatched embryos (25%). At the end of the exposure, no significant differences were observed in growth of the larvae exposed to the highest Cu concentration. However, larvae exposed to 2 µg/L Cu exhibited increased growth in comparison with non-exposed larvae. The percentage of malformed larvae was significantly higher for both copper conditions, with skeletal malformations being the most observed. Expression of several genes was evaluated in whole larvae using quantitative real-time PCR. Genes involved in detoxification (gst, mt1 and mt2) and in cell cycle arrest (p53) were significantly repressed in both copper conditions when compared to control. In addition, potential genotoxic effects on larvae were investigated by the comet assay on blood cells, but this test did not demonstrate any significant DNA damage on larvae exposed to copper. This study confirms the adverse effects of copper on early life stages of rainbow trout even at the lowest environmentally relevant tested concentration.

ORTHODONTIC AND ORTHOPEDIC REHABILITATION OF PATIENTS WITH CLEFT OF UPPER LIP, ALVEOLAR SURGERY, HARD AND SOFT PALATE

The problem of children’s rehabilitation with cleft palate is multi edged and complex. The ultimate goal of rehabilitation measures is to restore the anatomical integrity of the tissues of the hard and soft palate, the function of the articulatory and mastication systems, create conditions for correct speech and maximum aesthetic rehabilitation.&#x0D; Orofacial cleft leads to the appearance of functional changes in breathing, sucking, chewing and swallowing. In the process of development of masticatory system, the formation of complex dentoalveolar anomalies in parallel with a significant decrease in masticatory efficiency, weakens the process of sound production, which leads to the formation of stable speech disorders. Such children from childhood form a sense of inferiority, they have reduced social adaptation due to the presence of a cosmetic defect and speech disorders.&#x0D; Optimization of orthodontic and orthopedic rehabilitation of patients with non-incision of the upper lip, alveolar process, hard and soft palate is actual clinical problem of modern dentistry.&#x0D; Typical orthodontic pathology in such patients is the development of the upper jaw with a significant narrowing of the upper dentition (due to cicatricial changes) and, as a result, the formation of a prognosis, often deep, bite. Possibilities for orthodontic treatment of such patients are significantly limited due to postoperative cicatricial changes, skeletal malformation of the upper jaw, partial upper teeth adentia, small alveolar bone volume, low dentoalveolar compensation capacity, high tendency to relapse, therefore, the completion of orthodontic treatment often requires a double denture.&#x0D; We propose to use milled caps and present a clinical case of their application.&#x0D; The stages of manufacturing milled cap are the following: making prints and the manufacture of models; superposition of the facial arch to determine the position of the upper jaw; determination of the central position of the lower jaw (by facial features, with functional tests and subsequent check of the state of the chewing muscles by EMG and the position of the joints with the help of CCPT), plastering the models in the articulator, 3D scanning and digitizing models and digital modeling of the cap with ZIRKONZAHN Scan.&#x0D; To make the cap, Multistratum flexible was used, which is a biocompatible elastic composite material with a low plaque build-up and high aesthetic characteristics, designed for the manufacture of cynoanatomical structures. Caps are recommended to be used day and night, even during meals. Caps are removed only for daily hygiene procedures.&#x0D; Thus, the milled cap allows solving practical problems in non-stunted patients with non-incision of the upper lip, alveolar process, hard and soft palate such as: to provide multiple occlusions without contacts and protected occlusion with stable position of the lower jaw; restore the full function of chewing; ensure maximum retention while maintaining the width of the upper dentition; significantly improve the aesthetics of the smile (the appearance of "white aesthetics") and the face (raising the height of the bite, improving the profile, the step of the lips, reducing the second chin, rotation of the lower jaw clockwise); create optimal conditions for further permanent prosthetics, since digital models can be used as reference points for future permanent non-removable structures.&#x0D; So, removable milled caps are the modern optimal method of temporary long-term prosthetics, which greatly improve the functional and aesthetic status of the patient.

Larsen syndrome: prenatal diagnosis – a report of three cases

Larsen syndrome is a rare congenital skeletal malformation (one in 100,000 births) caused by a generalized mesenchymal connective tissue disorder. This disorder leads to a broad spectrum of anomalies. Major diagnostic criteria are multiple dislocations of large joints (especially knees), short metacarpals with cylindrical non-tapering fingers, and anomalous facial features. Clinical spectrum is variable and it ranges from mild to lethal forms. Genetic aspect is also variable; sporadic occurrence as well as autosomal dominant and recessive inheritance have been described. In this study, the authors report on their experience\ by presenting three cases of Larsen syndrome diagnosed by prenatal ultrasound.

Alagille Syndrome and the Liver: Current Insights.

Alagille syndrome (ALGS) is an autosomal dominant disorder, with multisystem involvement, which usually occurs due to Notch signaling pathway defects, mostly due to JAG1 mutation (ALGS type 1), but rarely due to neurogenic locus notch homolog protein (NOTCH2) mutation (ALGS type 2). It was suspected in cases having at least three out of five major clinical criteria: cholestasis with a paucity of the bile duct, congenital cardiac defects, ocular posterior embryotoxon, typical facial features, and skeletal malformation. Till date, no early predictive marker for hepatic outcome in ALGS has found. No genotypic or, phenotype features or correlation could predict the development of endstage liver disease, which poses a unique management challenge. Cases with progressive liver damage, unremitting cholestasis and intractable pruritus often depend on liver transplantation as last resort. The cardiac, and renal status should be well accessed before liver transplant for the better post-transplantation outcome. Most of the clinical manifestations usually improve the following transplant, except any change in stature. The post liver transplantation outcome was usually comparable with other conditions which require liver transplantation as a last resort, but in this disease the effect of long term immunosuppression on other affected systems not evaluated well till date. Therefore long term post transplant prospective study is required to address these issues.How to cite this article: Singh SP, Pati GK. Alagille Syndrome and the Liver: Current Insights. Euroasian J Hepatogastroenterol, 2018;8(2):140-147

Integrated facial analysis and targeted sequencing identifies a novel KDM6A pathogenic variant resulting in Kabuki syndrome

Abstract Kabuki syndrome (KS) is a rare congenital mental retardation condition characterized by facial dysmorphia, visceral and skeletal malformations, and developmental delay. The integrated phenotype and genotype-based prioritization is critical for diagnoses of genetic diseases. In this study, a Chinese woman, presenting with characteristic facial features of KS, came for pre-pregnancy consultation. We aimed to clarify the diagnosis and provide pre-pregnancy genetic counseling. Facial dysmorphology analysis and next-generation sequencing-based multigene panel approach were used to identify candidate syndromes and causative variants, respectively. The candidate variant was verified by Sanger sequencing. We identified a novel de novo KDM6A pathogenic variant (c.3521G&gt;A) in the woman, which was in line with the Face2Gene analysis result. Peripheral blood RNA assay showed that the variant transcript underwent the nonsense-mediated mRNA decay and led to subsequent haploinsufficiency of KDM6A. Our study provides the genetic diagnosis method for KS type 2 and identifies the first KDM6A point variant in Chinese patient.

A recessive lethal chondrodysplasia in a miniature zebu family results from an insertion affecting the chondroitin sulfat domain of aggrecan

BackgroundCongenital skeletal malformations represent a heterogeneous group of disorders affecting bone and cartilage development. In cattle, particular chondrodysplastic forms have been identified in several miniature breeds. In this study, a phenotypic characterization was performed of an affected Miniature Zebu calf using computed tomography, necropsy and histopathological examinations, whole genome sequencing of the case and its parents on an Illumina NextSeq 500 in 2 × 150 bp paired-end mode and validation using Sanger sequencing and a Kompetitive Allele Specific PCR assay. Samples from the family of an affected Miniature Zebu with bulldog syndrome including parents and siblings, 42 healthy Miniature Zebu not related with members of the herd and 88 individuals from eight different taurine cattle breeds were available for validation.ResultsA bulldog-like Miniature Zebu calf showing a large bulging head, a short and compressed body and extremely short and stocky limbs was delivered after a fetotomy. Computed tomography and necropsy revealed severe craniofacial abnormalities including a shortening of the ventral nasal conchae, a cleft hard palate, rotated limbs as well as malformed and fused vertebrae and ribs. Histopathologic examination showed a disorganization of the physeal cartilage with disorderly arranged chondrocytes in columns and a multifocal closed epiphyseal plate. Whole-genome sequencing of this malformed Miniature Zebu calf, its dam and sire and subsequent comparative sequence analysis revealed a one base pair insertion (ACAN:c.5686insC) located within the cartilage development gene aggrecan (ACAN) exclusively homozygous in the affected calf and heterozygous in its parents. This variant was predicted to cause a frameshift (p.Val1898fsTer9) and thus a truncation of the chondroitin sulfate domain as well as a loss of the C-terminal globular domain of ACAN. It perfectly co-segregated with the lethal bulldog syndrome in Miniature Zebus.ConclusionsWe found a novel mutation in ACAN causing a recessive lethal chondrodysplasia in Miniature Zebu cattle. A diagnostic test for this mutation is now available for Miniature Zebu breeders preventing further cases of bulldog syndrome by targeted matings. To the authors’ best knowledge, this is the first case of a Miniature Zebu associated with an ACAN mutation.

Head skeleton malformations in zebrafish (Danio rerio) to assess adverse effects of mixtures of compounds

The EU-EuroMix project adopted the strategy of the European Food Safety Authority (EFSA) for cumulative risk assessment, which limits the number of chemicals to consider in a mixture to those that induce a specific toxicological phenotype. These so-called cumulative assessment groups (CAGs) are refined at several levels, including the target organ and specific phenotype. Here, we explore the zebrafish embryo as a test model for quantitative evaluation in one such CAG, skeletal malformations, through exposure to test compounds 0–120 hpf and alcian blue cartilage staining at 120 hpf, focusing on the head skeleton. Reference compounds cyproconazole, flusilazole, metam, and thiram induced distinctive phenotypes in the head skeleton between the triazoles and dithiocarbamates. Of many evaluated parameters, the Meckel’s–palatoquadrate (M–PQ) angle was selected for further assessment, based on the best combination of a small confidence interval, an intermediate maximal effect size and a gentle slope of the dose–response curve with cyproconazole and metam. Additional test compounds included in the CAG skeletal malformations database were tested for M–PQ effects, and this set was supplemented with compounds associated with craniofacial malformations or cleft palate to accommodate otherwise organized databases. This additional set included hexaconazole, all-trans-retinoic acid, AM580, CD3254, maneb, pyrimethanil, imidacloprid, pirimiphos-methyl, 2,4-dinitrophenol, 5-fluorouracil, 17alpha-ethynylestradiol (EE2), ethanol, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), PCB 126, methylmercury, boric acid, and MEHP. Most of these compounds produced a dose–response for M–PQ effects. Application of the assay in mixture testing was provided by combined exposure to cyproconazole and TCDD through the isobole method, supporting that in this case the combined effect can be modeled through concentration addition.

Effects of low doses Trichlorfon exposure on Rana chensinensis tadpoles.

Trichlorfon is an organophosphate insecticide widely used in aquaculture and agriculture. Little is known about the effects of long-term of low doses trichlorfon exposure on amphibians. In this study, we investigated the effects of low doses trichlorfon on Rana chensinensis tadpoles after exposure to 0.01, 0.1, and 1.0 mg/L trichlorfon for 2 and 4 weeks. Survival, growth, development and mortality were monitored regularly over the course of exposure. The results showed that trichlorfon led to a decrease in tadpole survival. Reductions in growth and disruptions to the development of tadpoles were observed in trichlorfon treatments. Morphological abnormalities of affected tadpoles included axial flexures, skeletal malformations and lateral kinks. Trichlorfon increased the frequency of micronucleus (MN) formation in circulating erythrocytes of tadpoles exposed for 2 weeks to 0.1 and 1.0 mg/L trichlorfon. At all concentrations, an enhanced frequency of MN formation was observed in tadpoles exposed for 4 weeks. Exposure to trichlorfon induced other nuclear abnormalities such as lobed and notched nuclei only in tadpoles exposed to 1.0 mg/L trichlorfon for 4 weeks. In addition, exposure to trichlorfon within the 0.01-1.0 mg/L range increased the genetic damage index in hepatic tissues in all treatments. Apoptosis-associated DNA fragmentation in hepatic tissues occurred in a weak ladder-like pattern. This study presents evidence of low doses trichlorfon effects on amphibians, highlighting the properties of this organophosphate insecticide that jeopardize nontarget species exposed to trichlorfon.

Spinal manifestations in 12 patients with musculocontractural Ehlers-Danlos syndrome caused by CHST14/D4ST1 deficiency (mcEDS-CHST14).

Musculocontractural Ehlers-Danlos syndrome caused by mutations in CHST14 (mcEDS-CHST14) is a recently delineated disorder, characterized by craniofacial, skeletal, visceral, and ocular malformations; and progressive cutaneous, skeletal, vascular, and visceral fragility-related manifestations. Spinal lesions, though one of the most serious complications, have not been investigated systematically. In this study, we report detailed and comprehensive information about spinal lesions of 12 patients with a mean age at the first visit of 13.4 years. Eight patients (66.7%) had scoliosis with a Cobb angle ≥10°, including one with severe scoliosis with a Cobb angle ≥45°. Five patients (41.7%) had kyphosis at the thoracolumbar junction with a kyphotic angle ≥20°. Three patients (25%) developed severe thoracolumbar kyphosis with a kyphotic angle ≥50° accompanied by thoracic lordosis with a wedge-like vertebral deformity and anterior vertebral osteophyte at the thoracolumbar junction, and two of them underwent surgical correction: complicated by fistula formation in one and performed safely and effectively through two-staged operation in the other. Six patients (50.0%) had cervical kyphosis, all of whom except one had kyphosis ≥20° at the thoracolumbar level. Two patients (16.7%) had atlantoaxial subluxation, and 10 patients (83.3%) had cervical vertebral malformations. Patients with mcEDS-CHST14 are susceptible to develop scoliosis, thoracolumbar kyphosis, and cervical kyphosis; and are recommended to have regular surveillance including total spine radiology. The present findings also suggest the critical role of dermatan sulfate in the development and maintenance of the spine.