Caries infiltrant combined with conventional adhesives for sealing sound enamel in vitro

Objective:To test the null hypothesis that combining low-viscosity caries infiltrant with conventional adhesive resins would not improve sealing of sound enamel against demineralization in vitro.Materials and Methods:Bovine enamel discs (N  =  60) with diameter of 3 mm were randomly assigned to six groups (n  =  10). The discs were etched with 37% phosphoric acid for 30 seconds and treated with resins of different monomer content forming the following groups: (1) Icon (DMG), (2) Transbond XT Primer (3M ESPE), (3) Heliobond (Ivoclar Vivadent), (4) Icon + Transbond XT Primer, and (5) Icon + Heliobond. Untreated etched samples served as the negative control. Specimens were subjected to demineralization by immersion in hydrochloric acid (pH 2.6) for 80 hours. Calcium dissolution into the acid was assessed by colorimetric analysis using Arsenazo III method at 16-hour intervals. Groups presenting high protection against demineralization were subjected to further acidic challenge for 15 days with calcium measurements repeated at 24-hour intervals. Data were analyzed by Kruskal-Wallis test and Mann-Whitney U-test.Results:Untreated specimens showed the highest amount of demineralization. Icon and Transbond XT primer decreased the mineral loss significantly compared to the control. Heliobond performed significantly better than both Icon and Transbond XT primer. Combination of Icon both with Transbond XT primer or Heliobond served as the best protective measures and maintained the protective effect for the additional 15-day acidic challenge.Conclusions:Within the limitations of this in vitro study, it could be concluded that the use of low-viscosity caries infiltrant prior to application of the tested conventional adhesives increases their protective effect against demineralization.     

LETHAL HYDROPS FETALIS DUE TO CONGENITAL DYSERYTHROPOIETIC ANEMIA IN A NEWBORN: Association of a New Skeletal Abnormality

Congenital dyserythropoietic anemias (CDAs) area group of hereditary refractory anemias characterized by ineffective erythropoiesis, typical morphological abnormalities of erythroblasts, a low or no reticulocyte response, hyperbilirubinemia, and splenomegaly. A massive hydropic newborn born with a very severe anemia (Hb 4.8 g/dL), diffuse edema, hepatosplenomegaly, ascites, pulmonary edema and respiratory distress, and shortness and hallux varus deformity of the great toe of the right foot was diagnosed to have congenital dyserythropoietic anemia on the basis of the hematological (macrocytosis, anisopoikilocytosis, fragmented red cells and erythroblastosis in the peripheral blood, and erythroid hyperplasia with erythroblastosis and erythroblasts with double nuclei and thin chromatin bridges connecting these nuclei in the bone marrow) and serological (negative acidified serum lysis test and no agglutination with anti-i antibodies) findings. In this article the seventh case of neonatal congenital dyserythropoietic anemia presenting with a very severe(lethal) form of hydrops fetalis and a new (hallux varus) deformity of the great toe of the right foot is presented. Congenital dyserythropoietic anemia should be considered in the differential diagnosis of hydrops fetalis presenting with a very severe anemia and a skeletal abnormality of the great toe.     

Dichlorvos-induced testicular toxicity in male rats and the protective role of vitamins C and E

Dichlorvos is an organophosphorus insecticide that is used worldwide for pest control in agriculture and household use. Vitamins C and E are potential antioxidants protecting cells from oxidative stress. Vitamin C + vitamin E, dichlorvos, a combination of vitamin C + vitamin E + dichlorvos, or corn oil (control) were given to rats via oral gavage for 7 weeks. Body and testis weights, sperm parameters, hormone levels, histo- and cytopathological changes in testes were investigated at the end of 24 h and the 4th and 7th weeks comparatively with the control group. Body and testis weights, sperm morphology, FSH, LH, and testosterone levels were decreased significantly at the end of 4th and 7th weeks in the dichlorvos- and vitamins + dichlorvos-treated groups. A statistically significant decline in sperm motility and testosterone levels occurred by the end of 7th week in the dichlorvos- and vitamins + dichlorvos-treated groups. Light and electron microscopy revealed necrosis, edema and cellular damage in testicular tissues of the dichlorvos- and vitamins + dichlorvos-treated rats at the end of 4th and 7th weeks. In conclusion, dichlorvos caused subacute and subchronic reproductive toxicity, but vitamins did not confer protection.     

Acute promyelocytic leukemia: where does it stem from?

A fundamental issue in cancer biology is the identification of the target cell in which the causative molecular lesion arises. Acute myeloid leukemia (AML) is thought to reflect the transformation of a primitive stem cell compartment. The resultant 'cancer stem cells' comprise only a minor portion of the leukemic clone but give rise through differentiation to more committed progenitors as well as differentiated blasts that constitute the bulk of the tumor. The maintenance of the leukemic clone is dependent on the self-renewal capacity of the cancer stem cell compartment, which is revealed by its ability to re-initiate leukemia in a transplant setting. The cellular basis of acute promyelocytic leukemia (APL) is however less clear. APL has traditionally been considered to be the most differentiated form of AML and to arise from a committed myeloid progenitor. Here we review apparently conflicting evidence pertaining to the cellular origins of APL and propose that this leukemia may originate in more than one cellular compartment. This view could account for many apparent inconsistencies in the literature to date. An understanding of the nature of the target cell involved in transformation of APL has important implications for biological mechanism and for clinical treatment.     

Myointimoma of the glans penis

Myointimoma is a recently described benign tumor, which is regarded as a rare type of mesenchymal tumor of the penis. The present patient was a 50-year-old man who had a nodule located in the glans penis. He had a 2 month history of a mass. An excisional biopsy was performed. The histological findings revealed a multinodular tumor that was characterized by spindle-shaped cells located in the intravascular area. This case, in addition to 11 cases reported in the literature, demonstrates that the myointimoma is frequently misdiagnosed on clinical and pathological grounds because of its rarity. Histological and immunohistochemical features are summarized on the basis of the present case and previously published reports.     

Directing oncogenic fusion genes into stem cells via an SCL enhancer

TEL-TRKC is a fusion gene generated by chromosomal translocation and encodes an activated tyrosine kinase. Uniquely, it is found in both solid tumors and leukemia. However, a single exon difference (in TEL) in TEL-TRKC fusions is associated with the two sets of cancer phenotypes. We expressed the two TEL-TRKC variants in vivo by using the 3' regulatory element of SCL that is selectively active in a subset of mesodermal cell lineages, including endothelial and hematopoietic stem cells and progenitors. The leukemia form of TEL-TRKC (-exon 5 of TEL) enhanced hematopoietic stem cell renewal and initiated leukemia. In contrast, the TEL-TRKC solid tumor variant (+ TEL exon 5) elicited an embryonic lethal phenotype with impairment of both angiogenesis and hematopoiesis indicative of an effect at the level of the hemangioblasts. The ability of TEL-TRKC to repress expression of Flk1, a critical regulator of early endothelial and hematopoietic cells, depended on TEL exon 5. These data indicate that related oncogenic fusion proteins similarly expressed in a hierarchy of early stem cells can have selective, cell type-specific developmental impacts.     

Evaluation of endothelialization in the center part of graft using 3 cm vascular grafts implanted in the abdominal aortae of the rat

In order to develop small-diameter vascular grafts, it is necessary to evaluate endothelialization, especially, in the center part at early stage. For implantation of vascular grafts of 1 cm in length to abdominal aortae of rat, endothelial cells can be formed easily by stretching anastomosis. We evaluated the endothelialization in the center part of vascular grafts by implanting vascular grafts using transgenic (TG) silk fibroin (SF) of 3 cm in length. Vascular grafts were prepared 1.5 mm in diameter and 1 and 3 cm in length using wild type (WT) SF and TG SF by braiding structure, respectively. The grafts were removed after 2 weeks or 3 months and evaluated pathologically. Endothelialization was not confirmed totally after 3 months of implantation. However, endothelialization in the center part of grafts was significantly higher in TG SF than in WT SF. No significant difference was found regarding tissue infiltration and internal diameter. The TG SF revealed migration of the endothelial cells into the center part of the vessels at the early stage. Also, tissue infiltration and remodeling is expected using SF. The 3 cm length vascular grafts can be evaluated as a new experimental system.