Prenatal skeletal dysplasia phenotype in severe MLII alpha/beta with novel GNPTAB mutation

We report a neonate who was diagnosed as a case of skeletal dysplasia during pregnancy, and was subsequently diagnosed as a case of MLII alpha/beta on the basis of clinical and radiological findings and molecular testing of the parents. A novel GNPTAB mutation c.1701delC [p.F566LfsX5] was identified in the father. The case reiterates the severe prenatal phenotype of MLII alpha/beta which mimics skeletal dysplasia and illustrates the utility of molecular genetic analysis in confirmation of diagnosis and subsequent genetic counselling.     

Validation of DNA test for hip dysplasia failed in Danish Labrador Retrievers

Canine hip dysplasia is characterized by poor hip joint conformation and laxity. The disease is a complex trait influenced by both genetics and environment. Diagnosis and quantification of hip dysplasia are performed by radiographic examination of the hip joint and the diagnosis is used for making breeding decisions in many breeds. A prognostic genetic test (the Dysgen test) based on seven associated SNPs has been developed in a study based on Spanish Labrador Retrievers. In our study this test has been evaluated in 39 Danish Labrador Retrievers with known radiographic hip score: 14 with hip dysplasia (grade D or E) and 25 without hip dysplasia (grade A or B). There was no significant correlation between the Dysgen test results and the radiographic hip status (P = 0.3203) in these dogs, indicating that Dysgen test results obtained for Danish Labrador Retrievers have no prognostic value.     

Osteoblasts from a mandibuloacral dysplasia patient induce human blood precursors to differentiate into active osteoclasts

Mandibuloacral dysplasia type A (MADA) is a rare disease caused by mutations in the LMNA gene encoding A type lamins. Patients affected by mandibuloacral dysplasia type A suffer from partial lipodystrophy, skin abnormalities and accelerated aging. Typical of mandibuloacral dysplasia type A is also bone resorption at defined districts including terminal phalanges, mandible and clavicles. Little is known about the biological mechanism underlying osteolysis in mandibuloacral dysplasia type A. In the reported study, we analyzed an osteoblast primary culture derived from the cervical vertebrae of a mandibuloacral dysplasia type A patient bearing the homozygous R527H LMNA mutation. Mandibuloacral dysplasia type A osteoblasts showed nuclear abnormalities typical of laminopathic cells, but they proliferated in culture and underwent differentiation upon stimulation with dexamethasone and beta-glycerophosphate. Differentiated osteoblasts showed proper production of bone mineral matrix until passage 8 in culture, suggesting a good differentiation activity. In order to evaluate whether mandibuloacral dysplasia type A osteoblast-derived factors affected osteoclast differentiation or activity, we used a conditioned medium from mandibuloacral dysplasia type A or control cultures to treat normal human peripheral blood monocytes and investigated whether they were induced to differentiate into osteoclasts. A higher osteoclast differentiation and matrix digestion rate was obtained in the presence of mandibuloacral dysplasia type A osteoblast medium with respect to normal osteoblast medium. Further, TGFbeta 2 and osteoprotegerin expression were enhanced in mandibuloacral dysplasia type A osteoblasts while the RANKL/osteoprotegerin ratio was diminished. Importantly, inhibition of TGFbeta 2 by a neutralizing antibody abolished the effect of mandibuloacral dysplasia type A conditioned medium on osteoclast differentiation. These data argue in favor of an altered bone turnover in mandibuloacral dysplasia type A, caused by upregulation of bone-derived stimulatory cytokines, which activate non-canonical differentiation stimuli. In this context, TGFbeta 2 appears as a major player in the osteolytic process that affects mandibuloacral dysplasia type A patients.     

Eight-alanine duplication in homeobox D13 in a Chinese family with synpolydactyly

Human synpolydactyly (SPD), belonging to syndactyly (SD) II, is an inherited autosomal-dominant limb malformation characterized by SD of finger 3 or 4 or toe 4 or 5, usually with digit duplication. Previous studies have demonstrated that homeobox protein D13 (HOXD13) is responsible for this Mendelian disorder. In this paper, we report on a family with SPD - 7 members show typical SPD malformations. We used PCR and Sanger sequencing of DNA from peripheral blood samples and found an 8-Ala expansion in exon 1 of HOXD13 by mutation detection; this variant was absent in unaffected members and in 50 unaffected non-related subjects. This study further confirmed the correlation between SPD and alanine expansion in HOXD13.     

Identification of three novel mutations in the COL2A1 gene in four unrelated Chinese families with spondyloepiphyseal dysplasia congenita

Introduction

Spondyloepiphyseal dysplasia congenita (SEDC) is an autosomal dominant skeletal dysplasia characterized by short stature, abnormal epiphyses, and flattened vertebral bodies. The condition occurs through a mutation in the COL2A1 gene that encodes the type II procollagen alpha1 chain (proalpha1 (II)).

Method and Results

We investigated nine affected individuals from four unrelated Chinese families with SEDC. We screened for COL2A1 gene mutations, and identified found four missense mutations (G447A, G456A, R789C and G1152D). The G447A, G456A and G1152D mutations are novel and the R789C mutation has been reported previously in several other studies with a strikingly similar phenotype.

Conclusions

Our study extends the mutation spectrum of SEDC and is helpful in early molecular diagnoses of SEDC.     

A Genetic Predictive Model for Canine Hip Dysplasia: Integration of Genome Wide Association Study (GWAS) and Candidate Gene Approaches

Canine hip dysplasia is one of the most prevalent developmental orthopedic diseases in dogs worldwide. Unfortunately, the success of eradication programs against this disease based on radiographic diagnosis is low. Adding the use of diagnostic genetic tools to the current phenotype-based approach might be beneficial. The aim of this study was to develop a genetic prognostic test for early diagnosis of hip dysplasia in Labrador Retrievers. To develop our DNA test, 775 Labrador Retrievers were recruited. For each dog, a blood sample and a ventrodorsal hip radiograph were taken. Dogs were divided into two groups according to their FCI hip score: control (A/B) and case (D/E). C dogs were not included in the sample. Genetic characterization combining a GWAS and a candidate gene strategy using SNPs allowed a case-control population association study. A mathematical model which included 7 SNPs was developed using logistic regression. The model showed a good accuracy (Area under the ROC curve = 0.85) and was validated in an independent population of 114 dogs. This prognostic genetic test represents a useful tool for choosing the most appropriate therapeutic approach once genetic predisposition to hip dysplasia is known. Therefore, it allows a more individualized management of the disease. It is also applicable during genetic selection processes, since breeders can benefit from the information given by this test as soon as a blood sample can be collected, and act accordingly. In the authors’ opinion, a shift towards genomic screening might importantly contribute to reducing canine hip dysplasia in the future. In conclusion, based on genetic and radiographic information from Labrador Retrievers with hip dysplasia, we developed an accurate predictive genetic test for early diagnosis of hip dysplasia in Labrador Retrievers. However, further research is warranted in order to evaluate the validity of this genetic test in other dog breeds.     

No skeletal dysplasia in the nariokotome boy KNM‐WT 15000 (homo erectus)—A reassessment of congenital pathologies of the vertebral column

The Nariokotome boy skeleton KNM‐WT 15000 is the most complete Homo erectus fossil and therefore is key for understanding human evolution. Nevertheless, since Latimer and Ohman (2001) reported on severe congenital pathology in KNM‐WT 15000, it is questionable whether this skeleton can still be used as reference for Homo erectus skeletal biology. The asserted pathologies include platyspondylic and diminutive vertebrae implying a disproportionately short stature; spina bifida; condylus tertius; spinal stenosis; and scoliosis. Based on this symptom complex, the differential diagnosis of spondyloepiphyseal dysplasia tarda, an extremely rare form of skeletal dysplasia, has been proposed. Yet, our reanalysis of these pathologies shows that the shape of the KNM‐WT 15000 vertebrae matches that of normal modern human adolescents. The vertebrae are not abnormally flat, show no endplate irregularities, and thus are not platyspondylic. As this is the hallmark of spondyloepiphyseal dysplasia tarda and related forms of skeletal dysplasia, the absence of platyspondyly refutes axial dysplasia and disproportionate dwarfism. Furthermore, we neither found evidence for spina bifida occulta nor manifesta, whereas the condylus tertius, a developmental anomaly of the cranial base, is not related to skeletal dysplasias. Other fossils indicate that the relatively small size of the vertebrae and the narrow spinal canal are characteristics of early hominins rather than congenital pathologies. Except for the recently described signs of traumatic lumbar disc herniation, the Nariokotome boy fossil therefore seems to belong to a normal Homo erectus youth without pathologies of the axial skeleton. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.     

Pulmonary hypertension in bronchopulmonary dysplasia

Pulmonary hypertension is common in bronchopulmonary dysplasia and is associated with increased mortality and morbidity. This pulmonary hypertension is due to abnormal microvascular development and pulmonary vascular remodeling resulting in reduced cross‐sectional area of pulmonary vasculature. The epidemiology, etiology, clinical features, diagnosis, suggested management, and outcomes of pulmonary hypertension in the setting of bronchopulmonary dysplasia are reviewed. In summary, pulmonary hypertension is noted in a fifth of extremely low birth weight infants, primarily those with moderate or severe bronchopulmonary dysplasia, and persists to discharge in many infants. Diagnosis is generally by echocardiography, and some infants require cardiac catheterization to identify associated anatomic cardiac lesions or systemic‐pulmonary collaterals, pulmonary venous obstruction or myocardial dysfunction. Serial echocardiography and B‐type natriuretic peptide measurement may be useful for following the course of pulmonary hypertension. Currently, there is not much evidence to indicate optimal management approaches, but many clinicians maintain oxygen saturation in the range of 91 to 95%, avoiding hypoxia and hyperoxia, and often provide inhaled nitric oxide, sometimes combined with sildenafil, prostacyclin, or its analogs, and occasionally endothelin‐receptor antagonists. Birth Defects Research (Part A) 100:240–246, 2014. © 2014 Wiley Periodicals, Inc.     

Cerumen phenotype and epithelial dysplasia in nipple aspirates of breast fluid

The relationship between presence of dysplastic epithelial cells in nipple aspirates of breast fluid and wet or dry cerumen phenotype was studied in 1,150 white and Asian American women. A statistically significant greater proportion of premenopausal white women of wet cerumen phenotype, compared to women of the dry cerumen type, was found to have cytologic dysplasia (relative risk 6.5 [1.8--22.3]). The effect was not observed in postmenopausal women. The finding offers new support for our hypothesis that an apocrine genetic factor affecting breast gland secretion may influence exposure of the breast epithelium to potential carcinogenic substances of exogenous or endogenous origin.     

Selective inactivation of LGI1 in neuronal precursor cells leads to cortical dysplasia in mice

Constitutional mutations in Leucine‐rich glioma inactivated 1 (LGI1) predispose to an autosomal dominant epilepsy syndrome in humans and germline inactivation of LGI1 in mice leads to early onset seizures. LGI1 is highly expressed in the regions involved in neuronal stem cell generation and migration and detailed analysis of the brains in these mice reveals a subtle cortical dysplasia characterized by hypercellularity in the outer cortical layers. To investigate the cellular origin for this cortical dysplasia, we created mice that allow cell‐specific, conditional inactivation of LGI1. Exons 3–4, which contain critical motifs for LGI1 function, were targeted for deletion and, using a CMV‐cre mouse strain, global inactivation of LGI1 led to early onset seizures and the same cortical dysplasia seen in the constitutionally null mice. Similarly, inactivation of LGI1 in cells expressing Nestin, expressed primarily in neuronal precursor cells, led to early onset seizures and cortical dysplasia. In contrast, targeting inactivation of LGI1 in cells expressing Gfap, Camk2a, and parvalbumin, did not lead to cortical dysplasia. This strain of mouse, therefore, allows for a more refined investigation of the cell types involved in the cortical dysplasia seen following inactivation of LGI1 and potentially a better understanding of the molecular mechanisms behind LGI1‐induced epilepsy.     

Mutation p.Leu354Pro in EDA causes severe hypohidrotic ectodermal dysplasia in a Chinese family

X-linked recessive hypohidrotic ectodermal dysplasia (XLHED) is characterized by the defective morphogenesis of teeth, hair, and eccrine sweat glands. It is associated with mutations in the EDA gene. Up to now, more than 100 mutations in the EDA gene have been reported to cause XLHED. The product of EDA gene is a trimeric type II transmembrane protein that belongs to the tumor necrosis factor (TNF) family of ligands. In this study, we identified a Chinese family with XLHED. Direct DNA sequencing of the whole coding region of EDA revealed a novel missense mutation, p.Leu354Pro in a patient affected with XLHED. This mutation was not found in either unaffected male individuals of the family or 168 normal controls. The substitution of Leu354 with Pro was found to be located in the TNF-like domain of EDA and may influence the epithelial signaling pathway required for the normal ectodermal development through altering the topology of EDA. Our finding broadens the spectrum of EDA mutations and may help to understand the molecular basis of XLHED and aid genetic counseling.     

The impact of liquid-based oral cytology on the diagnosis of oral squamous dysplasia and carcinoma

OBJECTIVE: Even though diagnostic oral exfoliative cytology is a useful, economical and practical tool in the diagnosis of oral dysplasia and carcinoma, it is not yet extensively used. The results of conventional exfoliative and liquid-based diagnostic cytology in oral potentially malignant lesions (PML) are herein reported and compared with the histological diagnosis. METHODS: Either conventional (89) or liquid-based (384) exfoliative cytology was used for the diagnosis of oral dysplasia/carcinoma in 473 subjects and the results were compared with scalpel biopsy histology. Cells were collected using a Cytobrush device for conventional smears and with a dermatological curette for the liquid-based cytology. The 'curette technique' also allowed for the collection of 'accidental' tissue fragments, utilized as microbiopsies. RESULTS: Histological diagnosis was squamous carcinoma in 96 of 473 cases, high-grade dysplasia (oral intraepithelial neoplasia two to three) in 24 and other lesions in 353 cases. The smears in the conventional cytology group were inadequate in 12.4%, with an 85.7% sensitivity and a 95.9% specificity. There were 8.8% of inadequate specimens in the liquid-based cytology group; sensitivity was 95.1% and specificity was 99.0%. CONCLUSIONS: Although conventional cytology is useful when diagnosing oral PML (better sensitivity and predictive positive value if compared with the cervical smear test with similar specificity) and can improve the accuracy of histological diagnosis, liquid-based cytology gives better results, as it not only enhances both sensitivity and specificity, but also provides material for further investigation (AgNORs, DNA, microbiopsies, etc.).     

hERG1 Potassium Channel Expression in Colorectal Adenomas: Comparison with Other Preneoplastic Lesions of the Gastrointestinal Tract

Preneoplastic lesions represent a useful target for early diagnosis and follow-up of gastrointestinal malignancies. hERG1 channel expression was tested by immunohistochemistry (IHC) in a cohort of colorectal adenoma samples belonging to Italian subjects. Overall, hERG1 was expressed in 56.5% of cases with both high staining intensity and a high percentage of positive cells. Moreover, hERG1 was expressed in a higher percentage of dysplastic adenomas with respect to hyperplastic lesions, and the proportion of positive samples further increased in patients with high-grade dysplasia. Comparing hERG1 expression in other preneoplastic lesions of the GI tract (gastric dysplasia and Barrett’s esophagus), it emerged that in all the conditions, hERG1 was expressed with a diffused pattern, throughout the cell, with variable staining intensity within the samples. The highest expression was detected in gastric dysplasia samples and the lowest in Barrett’s esophagus at similar levels observed in colorectal adenomas. Our results show that hERG1 is aberrantly expressed in human preneoplastic lesions of the gastrointestinal tract and has a different pattern of expression and role in the different sites. Overall, the detection of hERG1 expression in preneoplastic lesions could represent a novel diagnostic or prognostic marker of progression in the gastrointestinal tract.     

Post-translational modification of glutamine and lysine residues of HIV-1 aspartyl protease by transglutaminase increases its catalytic activity

The human immunodeficiency virus type 1 aspartyl protease (HIV-1 PR) is a homodimeric aspartyl endopeptidase that is required for virus replication. HIV-1 PR was shown to act invitro as acyl-donor and -acceptor for both guinea pig liver transglutaminase (TG, EC 2.3.2.13) and human Factor XIIIa. These preliminary evidences suggested that the HIV-1 PR contains at least three TG-reactive glutaminyl and one lysyl residues. We report here that the incubation of HIV-1 PR with TG increases its catalytic activity. This increase is dependent upon the time of incubation, the concentration of TG and the presence of Ca²⁺. Identification of ε-(γ-glutamyl)lysine in the proteolytic digest of the TG-modified HIV-1 PR suggested intramolecular covalent cross-linking of this protease which may promote a non-covalent dimerization and subsequent activation of this enzyme via a conformational change. This hypothesis is supported by the observation that the TG-catalyzed activation of HIV-1 PR was completely abolished by spermidine (SPD) which acts as a competitive inhibitor of ε-(γ-glutamyl)lysine formation. Indeed, in the presence of 1 mM SPD the formation of the isopeptide was decreased of about 80%. The main products of the TG-catalyzed modification of HIV-1 PR in the presence of SPD were N₁-mono(γ-glutamyl)SPD and N₈-mono(γ-glutamyl)SPD. Negligible amount of N₁,N₈-bis(γ-glutamyl)SPD were found. The significance of these results is discussed with respect to the activation of the protease by post-translational modification and design of potential inhibitors.     

胃异型增生上皮和胃腺癌神经内分泌分化的检测

目的检测胃异型增生上皮及胃腺癌组织中神经内分泌的表达.方法应用免疫组织化学法检测10例正常胃粘膜、63例癌旁低度异型增生、26例高度异型增生及相应胃腺癌组织中嗜铬粒蛋白A(CgA)、突触素(Syn)和神经元特异性烯醇化酶(NSE)表达结果 CgA、Syn和NSE在癌旁低度异型增生、高度异型增生及相应胃腺癌组织中阳性表达率有显著性差异(P<0.01).结论胃异型增生上皮和胃腺癌伴神经内分泌是一种常见的现象,它反映了胃腺癌发生发展的多步骤过程.     

A role for spermidine in the bolting and flowering of Arabidopsis

Several lines of experimental evidence indicate a close connection between polyamines (PAs) and reproductive development in Arabidopsis thaliana . (l) Measurement of the titers of endogenous spermidine (SPD) and putrescine (PUT), extracted from various organs of two ecotypes and a genetic line of Arabidopsis , revealed that flowers had the highest titers of both PAs, with SPD predominating. (2) In aseptic cultures of whole plants of the ecotype Columbia, the application of appropriate enzyme inhibitors lowered SPD titer while almost completely preventing bolting and flowering. When the plants were removed to an inhibitor-free medium, bolting and flowering resumed. (3) SPD added to the medium of aseptically cultured plants of Columbia growing under short-day (SD) conditions, where flowering is naturally delayed, increased the SPD titer and augmented the rate and extent of flowering. Under long-day (LD) conditions, where flowering is already rapid and abundant, it did not promote flowering any further. (4) Enzyme inhibitors of SPD synthesis given shortly before the transition from SD conditions to LD conditions prevented flowering. (5) In a delayed-flowering mutant ( CS 3123 ), the addition of SPD significantly accelerated flowering.     

转化生长因子5在发育性髋关节发育不良中的作用研究进展

发育性髋关节发育不良(developmental dysplasia of the hip,DDH)是一种主要因髋臼、股骨近端和关节囊等存在结构性畸形而导致的不稳定关节病变,进而发展成为髋关节的脱位。髋关节内软骨发育不良、骨骼及肌腱的异常均可导致髋关节结构的畸形,最终造成DDH。因此,早期预防与诊断是DDH治疗的关键。研究表明,DDH具有遗传基础,其易感基因包括GDF5、HOXD9、COL2AL、PAPPA2等,其中遗传因子转化生长因子5(growth differentiation factor 5,GDF5)对软骨细胞的增殖、分化具有重要作用,是当前研究治疗DDH的热点之一。因而,了解GDF5基因对软骨发育及分化的影响,对于DDH的发病机制和治疗具有重要意义。基于此,综述了国内外近期探讨的GDF5在基因层面上对DDH的影响,以及通过关节内注射重组人GDF5等基于GDF5的DDH治疗方案,以期为DDH的临床治疗提供新的策略。     

Pavlik吊带治疗早期发育性髋关节脱位的研究进展

发育性髋关节脱位(Developmental dysplasia of the hip,DDH)是指一系列髋关节结构异常的疾病,病变严重程度涵盖轻度髋臼发育不良到不可逆的髋关节脱位。DDH的治疗手段进展迅速,但早期闭合复位使用最多的仍是Pavlik吊带。通过超声可监测髋关节复位情况从而评估Pavlik吊带的治疗效果。同时,随着超生髋关节检查技术在我国的推广,使得早期诊断DDH成为可能,这也促进了Pavlik吊带在临床的应用。未来研究的方向在于制定基于询证医学证据的Pavlik吊带使用规范和开发出效果更好、并发症更少的新型支具。     

Vascular mediators in chronic lung disease of infancy: Role of endothelial monocyte activating polypeptide II (EMAP II)

Bronchopulmonary dysplasia (BPD) is a chronic lung disease of prematurity. Over the years, the BPD phenotype has evolved, but despite various advances in neonatal management approaches, the reduction in the BPD burden is minimal. With the advent of surfactant, glucocorticoids, and new ventilation strategies, BPD has evolved from a disease of structural injury into a new BPD, marked by an arrest in alveolar growth in the lungs of extremely premature infants. This deficient alveolar growth has been associated with a diminution of pulmonary vasculature. Several investigators have described the epithelial / vascular co‐dependency and the significant role of crosstalk between vessel formation, alveologenesis, and lung dysplasia's; hence identification and study of factors that regulate pulmonary vascular emergence and inflammation has become crucial in devising effective therapeutic approaches for this debilitating condition. The potent antiangiogenic and proinflammatory protein Endothelial Monocyte Activating Polypeptide II (EMAP II) has been described as a mediator of pulmonary vascular and alveolar formation and its expression is inversely related to the periods of vascularization and alveolarization in the developing lung. Hence the study of EMAP II could play a vital role in studying and devising appropriate therapeutics for diseases of aberrant lung development, such as BPD. Herein, we review the vascular contribution to lung development and the implications that vascular mediators such as EMAP II have in distal lung formation during the vulnerable stage of alveolar genesis. Birth Defects Research (Part A) 100:180–188, 2014. © 2014 Wiley Periodicals, Inc.