Effect of human cytomegalovirus infection on the expression of Hoxb2 and Hoxb4 genes in the developmental process of cord blood erythroid progenitors.

The aim of the present study was to investigate the role of Hoxb2 and Hoxb4 gene expression induced by human cytomegalovirus (HCMV) and/or all-trans retinoic acid (ATRA) on the proliferation and committed differentiation process of human cord blood hematopoietic stem cells (HSCs) to colony-forming erythroid progenitor cells (CFU-Es) in vitro. Cord blood was collected from the fetal placenta umbilical vein in 12 cases and cultured using hematopoietic stem cell culture technique in vitro. The proliferation and differentiation of cord blood HSCs to CFU-Es were continuously disrupted with HCMV-AD169 and/or 6 x 10⁻8 mol/l of ATRA. Expression levels of the Hoxb2 and Hoxb4 genes in the blank, ATRA, HCMV-AD169 and ATRA + HCMV treatment groups of CFU-Es were detected on day 3, 7 and 10 of culture by fluorescent quantitative reverse transcriptase-polymerase chain reaction method. Hoxb2 and Hoxb4 gene expression in each group began on day 3, obviously increased on day 7 and reached a peak on day 10. The expression levels of the Hoxb2 and Hoxb4 genes in the HCMV group were obviously down-regulated compared with the level in the blank group. However, expression levels of the Hoxb2 and Hoxb4 genes were significantly up-regulated in the HCMV + ATRA group compared with the HCMV group (P<0.05). Abnormal expression of the Hoxb2 and Hoxb4 genes induced by HCMV may play important roles in abnormal hematopoietic damage. They were also correlated with the process of erythroid hematopoiesis. ATRA (6 x 10⁻8 mol/l) significantly up-regulated expression of the Hoxb2 and Hoxb4 genes in the normal erythroid progenitor cells and in those cells infected with HCMV as well.

[Effect of ATRA on the expression of genes Hoxb2 and Hoxb4 in cord blood erythroid progenitors].

This study was aimed to investigate the expressions of genes hoxb2 and hoxb4 after interference of the proliferation and differentiation of hematopoietic stem cells (HSC) to the erythroid progenitors (CFU-E) in vitro by using all-trans retinoic acid (ATRA). The cord blood was collected from 12 cases of fetal placenta umbilical vein and cultured by using culture technique of HSC in vitro. The proliferation and differentiation of HSC to CFU-E were interfered with 6 x 10(-8) mol/L of ATRA. The expression levels of genes hoxb2 and hoxb4 in blank control and ATRA groups were detected by FQ-RT-PCR on day 3, 7 and 10 of culture. The results showed that the expressions of genes Hoxb2 and hoxb4 were a little on day 3, obviously increased on day 7 and reached highest level on day 10 in 2 groups. The expression level of hoxb4 on day 3, 7 and 10 in blank control group was obviously higher than expression level of hoxb2. As compared with blank control group, the expressions of genes hoxb2 and hoxb4 in the ATRA group were significantly up-regulated. It is concluded that the genes hoxb2 and hoxb4 all expressed in process of proliferation and differentiation to erythroid progenitors, which suggests that hoxb2 and hoxb4 relate to erythroid hematopoiesis, and the hoxb4 has more great relevance to erythroid hematopoiesis as compared with hoxb2. The ATRA (6 x 10(-8) mol/L) can up-regulate the expression of hoxb2 and hoxb4 significantly.

[Effect of cluster a in Hox gene on proliferation and differentiation of hematopoietic stem/progenitor cells and its relation to leukemia -- review].

In recent years, Research shows that cluster A of Hox gene family is a group of master genes for proliferation and differentiation of hematopoietic stem/progenitor cells (HSPCs), which influence on the number of hematopoietic stem cells and the differentiation of HSPCs into erythroid, myeloid, megakaryocytic and lymphocytic lineages, and are closely related with the pathogenesis of leukemia. In this review, the effects of gene Hox on proliferation and differentiation of HSPCs were concerned, while the epigenetics alterations of cluster A in Hox gene family as well as its coexistence with Non-HOX and other fusion genes were also discussed. This made cluster A in Hox gene family plays a regulatory role in pathogenesis of leukemia.

The topographical relationships and anastomosis of the nerves in the human internal auditory canal.

INTRODUCTION: The anatomy of the nerves in the human internal auditory canal (IAC) has been reported by a number of authors, and there are some differences among the viewpoints of the literatures. With the development of the microsurgery and endoscopic surgery in the IAC, the study of the topographical relationship of the nerves in the human IAC becomes more and more important. The purpose of this study was to investigate the anastomosis and topographical relationship of the nerves in the human IAC. METHODS: In this study, we dissected 30 human temporal bones from 15 heads, and examined the topographical relationship and the anastomosis of the nerves in human IAC. RESULTS: (1) In 11 out of 30 cases (37%), the facial nerve is anterosuperior to the vestibulocochlear nerve through the whole IAC; and for the remaining 19 cases (63%), the facial nerve rotates anteroinferiorly at an angle ranging from 30 degrees to 90 degrees , which is in the same direction as that of the cochlear. (2) Vestibulofacial nerve anastomosis occurs in 25 cases (83%), of which 67% appears near the porus acusticus, and of which 33% appears between the lateral and intermedial portion of IAC. The diameter was about 0.5-1 mm. (3) Vestibulocochlear anastomosis occurs in 24 cases (80%) among which, some brush-like nerve fiber bundles of the cochlear nerve were seen to enter the acculus proprius directly in 13 cases. Transverse vestibulocochlear anastomosis in the fundus of internal acoustic meatus occurred in 15 cases, including two cases with more anastomosis. No vestibulocochlear nerve anastomosis was found in six cases in this study. CONCLUSIONS: Our study shows that the Vestibulofacial nerve anastomosis and the vestibulocochlear nerve anastomosis do exist, and some variations appear due to individual differences. The appearance of the facial and vestibulocochlearnerves is variable but follows certain consistent patterns.

[Evaluation of perioperative blood loss following total knee arthroplasty].

OBJECTIVE: To evaluate perioperative occult blood loss following total knee arthroplasty (TKA). METHODS: A retrospective analysis of 40 patients undergoing TKA was conducted to calculate the mean blood loss and occult blood loss according to Gross formula. RESULTS: The mean total blood loss was 1538 ml in these cases with occult blood loss of 791 ml. In patients with autologous blood transfusion, the mean total blood loss was 1650 ml with occult blood loss of 786 ml. In patients without autologous blood transfusion, the mean total blood loss was 1370 ml with occult loss of 798 ml. CONCLUSION: TKA often results in large volume of occult blood loss in the perioperative period which can not be fully compensated by autologous blood transfusion, and additional blood supply is needed for maintenance of the circulating volume.