Proliferation and tenogenic differentiation of bone marrow mesenchymal stem cells in a porous collagen sponge scaffold.

BACKGROUND: Collagen is one of the most commonly used natural biomaterials for tendon tissue engineering. One of the possible practical ways to further enhance tendon repair is to combine a porous collagen sponge scaffold with a suitable growth factor or cytokine that has an inherent ability to promote the recruitment, proliferation, and tenogenic differentiation of cells. However, there is an incomplete understanding of which growth factors are sufficient and optimal for the tenogenic differentiation of rat bone marrow mesenchymal stem cells (BMSCs) in a collagen sponge-based 3D culture system. AIM: To identify one or more ideal growth factors that benefit the proliferation and tenogenic differentiation of rat BMSCs in a porous collagen sponge scaffold. METHODS: We constructed a 3D culture system based on a type I collagen sponge scaffold. The surface topography of the collagen sponge scaffold was observed by scanning electron microscopy. Primary BMSCs were isolated from Sprague-Dawley rats. Cell survival on the surfaces of the scaffolds with different growth factors was assessed by live/dead assay and CCK-8 assay. The mRNA and protein expression levels were confirmed by quantitative real-time polymerase chain reaction and Western blot, respectively. The deposited collagen was assessed by Sirius Red staining. RESULTS: Transforming growth factor ß1 (TGF-ß1) showed great promise in the tenogenic differentiation of BMSCs compared to growth differentiation factor 7 (GDF-7) and insulin-like growth factor 1 (IGF-1) in both the 2D and 3D cultures, and the 3D culture enhanced the differentiation of BMSCs into tenocytes well beyond the level of induction in the 2D culture after TGF-ß1 treatment. In the 2D culture, the proliferation of the BMSCs showed no significant changes compared to the control group after TGF-ß1, IGF-1, or GDF-7 treatment. However, TGF-ß1 and GDF-7 could increase the cell proliferation in the 3D culture. Strangely, we also found more dead cells in the BMSC-collagen sponge constructs that were treated with TGF-ß1. Moreover, TGF-ß1 promoted more collagen deposition in both the 2D and 3D cultures. CONCLUSION: Collagen sponge-based 3D culture with TGF-ß1 enhances the responsiveness of the proliferation and tenogenic differentiation of rat BMSCs.

Downregulation of glucose-6-phosphate dehydrogenase contributes to diabetic neuropathic pain through upregulation of toll-like receptor 4 in rats.

BACKGROUND AND AIM: Diabetic neuropathic pain is a refractory and disabling complication of diabetes mellitus. The pathogenesis of the diabetic neuropathic pain is still unclear, and treatment is insufficient. The aim of this study is to investigate the roles of glucose-6-phosphate dehydrogenase (G6PD) and toll-like receptor 4 (TLR4) in neuropathic pain in rats with diabetes. METHODS: Type 1 diabetes model was induced by intraperitoneal injection of streptozotocin (STZ, 75 mg/kg) in adult female Sprague-Dawley rats. Paw withdrawal threshold and paw withdrawal latency of rats were measured by von Frey filaments and thermal radiation, respectively. The expressions of G6PD and TLR4 in L4-L6 dorsal root ganglions (DRGs) were measured by western blotting and quantitative real-time polymerase chain reaction analysis. Fluorescent immunohistochemistry was employed to detect expressions of G6PD and TLR4 and co-location of G6PD with TLR4. RESULTS: The mRNA and protein expression levels of G6PD in DRGs were significantly decreased in diabetic rats when compared with age-matched control rats. Upregulation of G6PD by intrathecal injection of G6PD overexpression adenovirus markedly attenuated hindpaw pain hypersensitivity of diabetic rats. The mRNA and protein expression levels of TLR4 in DRGs of diabetic rats were significantly increased when compared with control rats. Intrathecal injection of TLR4-selective inhibitor CLI-095 attenuated diabetic pain in dose- and time-dependent manners. Furthermore, G6PD and TLR4 were co-localized in DRG neurons. Intrathecal injection of G6PD overexpression adenovirus greatly reduced TLR4 expression, while intrathecal injection of CLI-095 had no significant effect on G6PD expression in diabetic rats. CONCLUSIONS: Our results suggest that decrease in G6PD expression was involved in diabetic peripheral neuropathic pain, which was most likely through upregulation of TLR4 expression in the DRGs of rats.

Trisomy 21 with t(5; 11) chromosomal translocation as new unfavorable cytogenetic abnormalities in pediatric acute myeloid leukemia type M2: One case report of nine-year follow-up and literature review.

We report one case of pediatric acute myeloid leukemia type 2 (AML-M2) who presented with karyotypic aberration of trisomy 21 with the t(5;11) chromosomal translocation. The patient achieved complete remission after two cycles of chemotherapy of daunorubicin, cytarabine and etoposide. Then, follow-up cytogenetic analysis from bone marrow cell cultures demonstrated a normal karyotype of 46, XY. After 9 years, the patient relapsed and the karyotypic abnormalities of trisomy 21 with t(5;11) reappeared. It was concluded that trisomy 21 with t(5; 11) is a new unfavorable cytogenetic aberration in AML-M2.

[Clinical and biological characteristics of childhood acute myeloid leukemia with EVI1 gene positive expression].

OBJECTIVE: To study the expression of ecotropic viral integration site (EVI1) gene in childhood acute myeloid leukemia (AML) and the clinical features of EVI1-positive children with AML. METHODS: The clinical data of EVI1-positive children with AML were collected and analyzed. RT-PCR and real-time quantitative PCR were used for qualitative and quantitative analysis of expression of EVI1. Flow cytometry (FCM) was used for determining the immunophenotypes of bone marrow cells. Multiparameter FCM was used for monitoring minimal residual disease. The karyotypes were determined. RESULTS: Of 241 children with AML, 33 (13.7%) were positive for EVI1 expression. There were no significant differences in age at first visit as well as the white blood cell count, hemoglobin level, and platelet count in peripheral blood between EVI1-positive and EVI1-negative children with AML (P>0.05), but EVI1-positive children had a significantly increased proportion of females compared with EVI1-negative children (P<0.05). The change in EVI1 expression was not synchronous with clinical remission and the change of MRD: some children had clinical remission or negative conversion of MRD before negative conversion of EVI1, while some had negative conversion of EVI1 before clinical remission or while MRD showed positive. EVI1 gene was usually co-expressed with other fusion genes. CD33 (100%), CD38 (88%), and HLADR (76%) were highly expressed in EVI1-positive children with AML. Abnormal chromosome structure or number was found in 15 patients. Compared with EVI1-negative children, EVI1-positive children had significantly lower complete remission rates after the first course of treatment (P<0.05). CONCLUSIONS: EVI1-positive children with AML have a poor short-term prognosis. In the development of AML, the activation of EVI1 gene is not isolated, but the result of interactions with other genes or chromosome abnormalities, and the mechanism of activation and its function need further study.

Poly[octa-µ-aqua-tetra-aqua-bis(µ(4)-5-sulfonatobenzene-1,3-dicarboxyl-ato)nickel(II)tetra-sodium].

In the crystal structure of the title compound, [Na(4)Ni(C(8)H(3)O(7)S)(2)(H(2)O)(12)](n), the Ni(II) cation occupies an inversion centre and is coordinated by the carboxyl groups of the sulfoisophthalate trianions and water mol-ecules in a distorted octa-hedral geometry. Two independent Na(I) atoms are connected by the carboxyl and sulfonate groups of the sulfoisophthalate ligands anions and water mol-ecules in a distorted octa-hedral geometry. The sulfoisophthalate ligands and coordinated water mol-ecules bridge the Ni(II) and Na(I) cations, forming a three-dimensional polymeric structure. Weak π-π stacking is present between parallel benzene rings [centroid-centroid distance = 3.9349 (10) Å]. Extensive O-H⋯O and C-H⋯O hydrogen bonding helps to stabilize the crystal structure.

Bis(1H-imidazole-κN)bis-(2-oxidopyridinium-3-carboxyl-ato-κO,O)nickel(II).

In the crystal structure of the title Ni(II) complex, [Ni(C(6)H(4)NO(3))(2)(C(3)H(4)N(2))(2)], the Ni(II) atom is located on a twofold rotation axis and is chelated by two oxidopyridiniumcarboxyl-ate anions and further cis-coordinated by two imidazole ligands in a distorted cis-N(2)O(4) octa-hedral geometry. The C-O bond distance of 1.2573 (19) Šfound for the non-coordinating O atom of the carboxyl-ate group indicates significant delocalization of π-electron density over this residue. Similarly, the C-O bond distance of 1.260 (2) Šin the heteroaromatic ring indicates delocalization between the deprotonated hydr-oxy group and the pyridinium ring. The uncoordinated carboxyl-ate O atom links with the imidazole and pyridinium rings of adjacent mol-ecules via N-H⋯O and C-H⋯O hydrogen bonding, leading to a two-dimensional array parallel to (100).

Tetra-aqua-bis(pyridine-3-sulfonato-κN)nickel(II).

In the mol-ecule of the title compound, [Ni(C(5)H(4)NO(3)S)(2)(H(2)O)(4)], the Ni(II) cation is located on an inversion center and is coordinated by four water mol-ecules and two pyridine-3-sulfonate anions with an NiN(2)O(4) distorted octa-hedral geometry. The face-to-face separation of 3.561 (5) Šbetween parallel pyridine rings indicates the existence of weak π-π stacking between the pyridine rings. The structure also contains inter-molecular O-H⋯O hydrogen bonding and weak C-H⋯O hydrogen bonding.

Bis(2,5-dihydroxy-benzoato-κO)bis-(1,10-phenathroline-κN,N')cadmium(II) 1.25-hydrate.

In the crystal structure of the title compound, [Cd(C(7)H(5)O(4))(2)(C(12)H(8)N(2))(2)]·1.25H(2)O, the Cd(2+) cation is coordinated by two phenanthroline (phen) mol-ecules and two 2,5-dihydroxy-benzoate (dhba) anions in a distorted octa-hedral geometry. The centroid-centroid distances of 3.809 (2) and 3.680 (2) Šbetween nearly parallel pyridine rings of the phen ligands and the benzene rings of dhba anions indicate that the dhba anions are involved in π-π stacking in the crystal structure. The face-to-face separation of 3.35 (3) Šbetween parallel phen ring systems also suggests π-π stacking between adjacent complex mol-ecules. The crystal structure contains extensive O-H⋯O and C-H⋯O hydrogen bonding.