ABSTRACT
DNA methylation is essential in X chromosome inactivation and genomic imprinting, maintaining repression of XIST in the active X chromosome and monoallelic repression of imprinted genes. Disruption of the DNA methyltransferase genes DNMT1 and DNMT3B in the HCT116 cell line (DKO cells) leads to global DNA hypomethylation and biallelic expression of the imprinted gene IGF2 but does not lead to reactivation of XIST expression, suggesting that XIST repression is due to a more stable epigenetic mark than imprinting. To test this hypothesis, we induced acute hypomethylation in HCT116 cells by 5-aza-2′-deoxycytidine (5-aza-CdR) treatment (HCT116-5-aza-CdR) and compared that to DKO cells, evaluating DNA methylation by microarray and monitoring the expression of XIST and imprinted genes IGF2, H19, and PEG10. Whereas imprinted genes showed biallelic expression in HCT116-5-aza-CdR and DKO cells, the XIST locus was hypomethylated and weakly expressed only under acute hypomethylation conditions, indicating the importance of XIST repression in the active X to cell survival. Given that DNMT3A is the only active DNMT in DKO cells, it may be responsible for ensuring the repression of XIST in those cells. Taken together, our data suggest that XIST repression is more tightly controlled than genomic imprinting and, at least in part, is due to DNMT3A.
Subject(s)
Humans , DNA Methylation/genetics , Epigenetic Repression/genetics , Genome, Human , Genome/genetics , Genomic Imprinting/genetics , Insulin-Like Growth Factor II/genetics , RNA, Long Noncoding/genetics , Azacitidine/administration & dosage , Azacitidine/analogs & derivatives , /genetics , DNA Methylation/drug effects , Gene Knockout Techniques , Genome, Human/drug effects , In Situ Hybridization, Fluorescence/methods , Microarray Analysis , Polymorphism, Single Nucleotide , Proteins/metabolism , RNA, Long Noncoding/metabolism , Real-Time Polymerase Chain Reaction/methods , Reverse Transcriptase Polymerase Chain Reaction/methodsABSTRACT
DNA methylation is essential in X chromosome inactivation and genomic imprinting, maintaining repression of XIST in the active X chromosome and monoallelic repression of imprinted genes. Disruption of the DNA methyltransferase genes DNMT1 and DNMT3B in the HCT116 cell line (DKO cells) leads to global DNA hypomethylation and biallelic expression of the imprinted gene IGF2 but does not lead to reactivation of XIST expression, suggesting that XIST repression is due to a more stable epigenetic mark than imprinting. To test this hypothesis, we induced acute hypomethylation in HCT116 cells by 5-aza-2'-deoxycytidine (5-aza-CdR) treatment (HCT116-5-aza-CdR) and compared that to DKO cells, evaluating DNA methylation by microarray and monitoring the expression of XIST and imprinted genes IGF2, H19, and PEG10. Whereas imprinted genes showed biallelic expression in HCT116-5-aza-CdR and DKO cells, the XIST locus was hypomethylated and weakly expressed only under acute hypomethylation conditions, indicating the importance of XIST repression in the active X to cell survival. Given that DNMT3A is the only active DNMT in DKO cells, it may be responsible for ensuring the repression of XIST in those cells. Taken together, our data suggest that XIST repression is more tightly controlled than genomic imprinting and, at least in part, is due to DNMT3A.
Subject(s)
DNA Methylation/genetics , Epigenetic Repression/genetics , Genome, Human , Genome/genetics , Genomic Imprinting/genetics , Insulin-Like Growth Factor II/genetics , RNA, Long Noncoding/genetics , Apoptosis Regulatory Proteins , Azacitidine/administration & dosage , Azacitidine/analogs & derivatives , DNA (Cytosine-5-)-Methyltransferase 1 , DNA (Cytosine-5-)-Methyltransferases/genetics , DNA Methylation/drug effects , DNA-Binding Proteins , Decitabine , Gene Knockout Techniques , Genome, Human/drug effects , HCT116 Cells , Humans , In Situ Hybridization, Fluorescence/methods , Microarray Analysis , Polymorphism, Single Nucleotide , Proteins/metabolism , RNA, Long Noncoding/metabolism , RNA-Binding Proteins , Real-Time Polymerase Chain Reaction/methods , Reverse Transcriptase Polymerase Chain Reaction/methods , DNA Methyltransferase 3BSubject(s)
Toxicology , Toxicology , Poisons , Poisoning , Toxins, Biological , Toxicology , BiochemistryABSTRACT
A detailed examination of the hands and feet was performed in a group of 34 patients affected by systemic lupus erythematosus (SLE), using low-dose mammographic film and Rank Xerox selenium plate, according to current diagnostic techniques. All patients presented articular symptoms (pain and arthralgia). The high incidence (38,8%) of patients with no radiographic evidence of bone damage-even though articular symptoms are present-is emphasized. In such cases, it is very difficult to distinguish SLE from rheumatoid arthritis, especially as far as therapeutic management and prognosis are concerned. The lack of any "pathognomonic" radiological sign of the lupus arthritis, in the hands as well as in the feet, is then stressed. Nevertheless, arthropathy in SLE is defined as a deforming non-erosive arthritis, with a typical symmetric distribution, affecting most commonly-according to incidence-the proximal interphalangeal and metacarpophalangeal joints. In the hand, arthropathy is referred to as Jaccoud's type arthritis, because it is characterized by joint deformities which can be corrected. In the foot, the main abnormalities include hallux valgus, subluxation of the metatarsophalangeal joints and widening of the forefoot.
Subject(s)
Foot/diagnostic imaging , Hand/diagnostic imaging , Lupus Erythematosus, Systemic/diagnostic imaging , Adult , Aged , Arthritis, Rheumatoid/diagnostic imaging , Diagnosis, Differential , Female , Foot Deformities, Acquired/diagnostic imaging , Hand Deformities, Acquired/diagnostic imaging , Humans , Male , Middle Aged , RadiographyABSTRACT
Basic calcium phosphate (BCP) crystal deposition can lead to periarticular collections associated with typical radiographic findings, most frequently observed in the shoulder. Moreover, these deposits may be revealed in other articular sites (i.e., wrist, hand, foot, elbow, hip, etc.). Initially, the calcium deposits may appear poorly defined (cloudlike); afterwards, they may reveal different patterns (linear, triangular or circular areas), changing in size, configuration and site. Adjacent bone may be normal, although osteoporosis, cystic lesions and reactive sclerosis are reported. The radiographic appearance of calcifications will depend upon the exact location of the deposits in the specific tendon of the rotator cuff, the adjacent bursae and the soft tissues.
Subject(s)
Calcinosis/diagnostic imaging , Calcium Phosphates/metabolism , Shoulder Joint , Adult , Aged , Calcinosis/metabolism , Crystallization , Female , Humans , Male , Middle Aged , Radiography , Shoulder Joint/diagnostic imaging , Tendons/diagnostic imaging , Tendons/metabolismABSTRACT
The cortical margin of the inferior end plate of lumbar vertebral bodies, in the frontal projection, frequently simulates the curvature of a bow, aimed cephalad. On lateral view, the two concavities are superimposed and lie in the posterior portion of the vertebral body. The aspect, called "Cupid's bow" must be considered a normal anatomic variant and should not be confused with diseases affecting the spine. The incidence and degree of the finding are discussed.
Subject(s)
Lumbar Vertebrae/diagnostic imaging , Adult , Aged , Diagnosis, Differential , Female , Humans , Lumbar Vertebrae/anatomy & histology , Male , Middle Aged , Radiography , Spinal Diseases/diagnostic imagingABSTRACT
The authors report on their two years experience about hypogastric transarterial embolization in the treatment of urinary bladder intractable neoplastic hemorrhage. They discuss about materials for embolization and treatment of pain for acute ischaemia secondary to embolization.
