[Effects of iron chelation therapy on allogeneic hematopoietic stem cell transplantation in myelodysplastic syndrome patients with iron overload]

OBJECTIVE

To investigate the effects of iron chelation therapy on hematopoietic reconstitution and related complications of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with myelodysplastic syndrome (MDS).

METHODS

Various clinical parameters were analyzed retrospectively in 57 MDS patients with iron overload who received allo-HSCT. According to the level of serum ferritin (SF) before transplantation divided patients into two groups: the effective treatment group (SF<1 000 μg/L) and iron overload group (SF≥1 000 μg/L).

RESULTS

①30/57 cases were received iron chelation treatment, 27/57 patients didn' t received iron chelating therapy before transplantation. 19/30 cases were in the effective treatment group, and the median SF level before transplantation was 561 (223-846) μg/L. 11/30 cases were in the iron overload group, and the median SF level before transplantation was 1 262 (1 100-2 352) μg/L. The median SF level was 1 540 (1 320-3 112) μg/L of 27 patients didn't received iron chelating therapy before transplantation. ② The rate of fully-engraftment in the effective treatment group and iron overload group was 19 cases (100.0% ) and 34 cases (89.5% ), myeloid reconstitution of 12(10-18) and 12(11-30) days respectively (P=0.441), and platelet reconstitution of 13(12-30) and 15 (10-32) days respectively (P=0.579). ③The infection risk rate of the effective treatment group was less than iron overload group [36.8% (7/19) vs 82.4% (28/34), P=0.002]. ④The incidence of aGVHD in effective treatment group was less than iron overload group [26.3%(5/19) vs 64.7%(22/34), P= 0.010]. All patients of the effective treatment group were Ⅰ/Ⅱ degree. 16 cases were Ⅰ/Ⅱ degree and 6 cases were Ⅲ/Ⅳ degree in the iron overload group. ⑤ 6 cases of iron overload group accepted iron chelation treatment early post-transplantation, and SF level decreased from 2 870 (2 205-3 580) μg/L to 1 270 (1 020-1 650) μg/L. ⑥The difference of median disease-free survival time between the effective treatment group and iron overload group was not statistically significant [28.9 (0.3-89.5) months vs 21.2(0.1-81.0) months, χ(2)=3.751, P=0.053].

CONCLUSIONS

Iron overload obviously increased transplant-related complications, and effective iron chelation therapy before transplantation significantly decreased the incidence of infection and degree of aGVHD, thereby reduced the non-relapse mortality in patients with MDS.

Deacetylation of tumor-suppressor MST1 in Hippo pathway induces its degradation through HBXIP-elevated HDAC6 in promotion of breast cancer growth

Reduction or loss of tumor-suppressor mammalian STE20-like kinase 1 (MST1) in Hippo pathway contributes to the tumorigenesis. However, the mechanism leading to reduction of MST1 in cancers remains poorly understood. In this study, we explored the hypothesis that the oncoprotein hepatitis B X-interacting protein (HBXIP) is involved in the reduction of MST1 in breast cancer. Immunohistochemical analysis of tissue microarrays revealed that the expression of HBXIP was negatively associated with that of MST1 in 98 clinical breast tissue samples. Then we found that HBXIP could posttranslationally downregulate MST1 in breast cancer cells. Mechanistically, we identified that MST1 could be acetylated on its lysine 35 residue in the cells. Strikingly, the treatment with trichostatin A, an inhibitor of histone deacetylases (HDACs), markedly increased the levels of MST1 acetylation and protein in the cells. Interestingly, the oncoprotein HBXIP could significantly inhibit acetylation of MST1, resulting in the reduction of MST1 protein. Notably, we revealed that the HDAC6 could reduce the protein levels of MST1 through deacetylation modification of MST1 in the cells. Moreover, our data revealed that HBXIP upregulated HDAC6 at the levels of mRNA and protein by activating transcription factor nuclear factor-κB. Deacetylation of MST1 promoted the interaction of MST1 with HSC70 in the cells, resulting in a lysosome-dependent degradation of MST1 via chaperone-mediated autophagy (CMA). Functionally, the reduction of tumor-suppressor MST1 mediated by HBXIP promoted the growth of breast cancer cells in vitro and in vivo. Thus we conclude that the deacetylation of MST1 mediated by HBXIP-enhanced HDAC6 results in MST1 degradation in a CMA manner in promotion of breast cancer growth. Our finding provides new insights into the mechanism of tumor-suppressor MST1 reduction in breast cancer.

[The clinical and bacterial features of Klebsiella pnuemoniae liver abscess]

OBJECTIVE

To summarize the clinical and bacterial features of Klebsiella pnuemoniae liver abscess (KPLA) in order to provide the basis for the diagnosis and treatment of KPLA.

METHODS

Retrospective study was conducted. One hundred and fifty-two medical records, from 3 teaching hospitals in Beijing, between January 2010 and December 2014, were collected. Among which 137 complete medical records were analyzed. String test was carried out to detect the hypermucoviscosity phenotype. PCR was performed to check the capsular serotype and the virulent genes. Disk diffusion method was operated to obtain the antimicrobial resistance rates. The results were analyzed by chi-square test.

RESULTS

KPLA occurred mostly in middle-aged, male and diabetes mellitus patients. 92.7% (127/137) patients had fever. 80.3% (110/137) of the KLPA were single abscess, among which 80.9% (89/110) were in the right lobe and 33.6% (46/137) had air cavities.74.5% (102/137) of the white blood cell count, 83.2% (114/137) of the neutrophils' percentage, 78.1% (107/137) of alanine aminotransferase and 51.8% (71/137) of the total billrubin were elevated. 87.5% (133/152) of the Klebsiella pnuemoniae (Kpn) appeared to be hypermucoviscous, K1 was the most popular serotype, the second was K2, and the positive rates of virulent genes rmpA and aerobactin were 82.9% (126/152) and 88.2% (134/152), respectively. Among the isolates from the KPLA without other hepatobiliary diseases, the portion of K1 serotype, the positive rates of rmpA and aerobactin were 65.7%, 94.9% and 96.0%, respectively, higher than those of the 28.9%, 50.0% and 68.4% from the KPLA with other hepatobiliary diseases, while the undefined serotype potion was lower (5.1% vs 26.3%), the differences were statistically significant (χ(2)=14.98, 38.40, 17.61, 10.65, all P<0.01). Most of Kpn were susceptible to antimicrobials.

CONCLUSIONS

KPLA has certain clinical features, and are mostly caused by hypervirulent isolates that are hypermucoviscous with rmpA and aerobactin genes. Most of the isolates are susceptible to antimicrobials.

Pathology of the lower nasolacrimal duct mucosa at multiple time points after lacrimal retrograde catheterization in rabbit

Lacrimal duct obstruction is a common eye disease, and obstruction of the nasolacrimal duct accounts for over 50% of these cases. Nasolacrimal duct obstruction is usually treated surgically. Lacrimal retrograde catheterization is a novel surgical approach with a high success rate and a relatively high recurrence rate. In this study, we examined the postoperative pathological changes in the lower nasolacrimal duct mucosa at multiple time points (2, 4, 6, 8, 10, 12, and 14 weeks) after retrograde lacrimal dilated drainage tube implantation in rabbits. One side of the nasolacrimal duct was obstructed in 14 rabbits. Compared to the control side, the 2-, 4-, 6-, and 8-week groups presented no obvious changes in hematoxylin and eosin (H&E)-stained tissue. The 10-week group presented isolated granulomas. The 12- and 14-week groups presented scattered granulomas. The granulomas were smaller and the density of fibroblasts was lower in the 12-week group compared with the 14-week group. Transforming growth factor-β1 immunohistochemistry resulted in strong immunoreactivity in the 14-week group and weak immunoreactivity in the 12-week group, and the difference was statistically significant (P < 0.05). Fibroblast apoptosis was observed in the 4- and 6-week groups, and disorganized fibers were observed in the 10-week group. Most fibroblasts in the 12- and 14-week groups were the active type with mechanocytes. Granulomas were induced after a long time by the implantation of silicone tubes in rabbits. Thus, recurrent obstructions of the nasolacrimal duct may be caused by granulomas, progressive fibrosis, and/or adhesion of the surrounding tissues.

Development of a real-time loop-mediated isothermal amplification assay for the sensitive and rapid detection of Listeria monocytogenes

A real-time loop-mediated isothermal amplification (RealAmp) assay for the detection of Listeria was developed. The RealAmp assay, using primers specific for the hemolysin-encoding hlyA gene, was verified using Listeria monocytogenes strains (n = 58) from different regions of the world. Both the sensitivity and specificity of the RealAmp assay were high. The RealAmp assay could detect 10(3) CFU ml(-1) within 30 min. A comparative evaluation of the RealAmp assay, the API Listeria assay, and the real-time PCR assay revealed that the RealAmp assay is simpler, faster, and has a higher specificity than the other two assays.

SIGNIFICANCE AND IMPACT OF THE STUDY

Conventional culture and molecular detection methods are always time consuming and require a specific laboratory infrastructure, thereby restricting their use for the rapid detection and diagnosis of pathogens. A real-time loop-mediated isothermal amplification (RealAmp) assay performed by ESEtube scanner to rapidly detect Listeria monocytogenes isolated from food was developed. The results showed that the RealAmp assay using the tube scanner was more efficient and precise than the conventional API Listeria assay and the real-time PCR assay.

Interim estimates of 2014/15 influenza vaccine effectiveness in preventing laboratory-confirmed influenza-related hospitalisation from the Serious Outcomes Surveillance Network of the Canadian Immunization Research Network, January 2015

Binary file ES_Abstracts_Final_ECDC.txt matches

BRAF mutation correlates with recurrent papillary thyroid carcinoma in Chinese patients

PURPOSE

We investigated correlations of somatic BRAF V600E mutation and RET/PTC1 rearrangement with recurrent disease in Chinese patients with papillary thyroid carcinoma (ptc).

METHODS

This prospective study included 214 patients with ptc histologically confirmed between November 2009 and May 2011 at a single institute.

RESULTS

We found somatic BRAF V600E mutation in 68.7% and RET/PTC1 rearrangement in 25.7% of the patients. Although BRAF mutation was not significantly associated with clinicopathologic features such as patient sex or age, multicentric disease, thyroid capsule invasion, tumour stage, or nodal metastasis, it was significantly associated with recurrent disease. Multivariate analysis revealed that BRAF mutation and tumour size were independent risk factors associated with recurrent disease, with odds ratios of 9.072 and 2.387 respectively. The area under the receiver operating characteristic curve increased 8.3% when BRAF mutation was added to the traditional prognostic factors, but that effect was statistically nonsignificant (0.663 vs. 0.746, p = 0.124). RET/PTC1 rearrangement and nodal metastasis were significantly associated in all patients (p = 0.042), marginally associated in ptc patients (p = 0.051), but not associated in microptc patients (p = 0.700). RET/PTC1 rearrangement was not significantly associated with recurrent disease.

CONCLUSIONS

BRAF positivity is an independent predictor of recurrent disease in ptc.

Analysis of mitochondrial respiratory-related genes reveals nuclear and mitochondrial genome cooperation in allotetraploid hybrid

An allotetraploid hybrid lineage derived from the distant hybridization of red crucian carp (Carassius auratus red var., ♀, 2n =100) × common carp (Cyprinus carpio L., ♂, 2n =100) was investigated for its mitochondrial and nuclear genome inheritance patterns. Based on liver transcriptomic data for this hybrid, red crucian carp, and common carp, we identified 94, 136, and 86 contigs corresponding to 41, 46, and 37 mitochondrial respiratory chain nuclear genes, respectively. Mitochondrial respiratory chain nuclear gene sequences from red crucian carp and common carp were both detected in the allotetraploid hybrid, indicating that both parental nuclear genomes were participated in the synthesis of mitochondrial respiratory protein complexes in the hybrid. For mitochondrial respiratory related genes, high sequence similarity (>90%) and a low nucleotide divergence rate (<0.2) between red crucian carp and common carp could be a critical factor allowing cooperation of the three genomes (red crucian carp mitochondrial genome, red crucian and common carp nuclear genomes) in the allotetraploid hybrid lineage. Interestingly, gene duplication events were identified in the allotetraploid hybrid, red crucian and common carp, as confirmed by analysis of orthologous gene trees for these fish. Our findings provide valuable information with which to study cooperation between the nuclear and mitochondrial genomes of other hybrids, and will provide basic genetic information of relevance to mitochondrial-related diseases in humans and animals.

Molecular epidemiology and virulence factors of pyogenic liver abscess causing Klebsiella pneumoniae in China

The molecular epidemiology and prevalence of virulence factors of isolates from patients with Klebsiella pneumoniae liver abscess (KLA) in mainland China are unknown. Klebsiella pneumoniae isolates were obtained from drainage samples aseptically collected from patients with pyogenic liver abscess (PLA). The genetic similarity of KLA isolates was analyzed by pulsed-field gel electrophoresis. The hypermucoviscosity (HV) phenotype was identified by a positive string test. The K1 and K2 genotypes, the pLVPK-derived genetic loci, aerobactin gene, kfu and alls were detected by PCR amplification. The sequence types (STs) were identified by multilocus sequence typing. Among the 51 non-repetitive KLA isolates, 49 PFGE types have been identified. In total, 19 (37.2%) and 14 (27.4%) of the 51 KLA isolates belonged to clonal complex (CC) 23 and CC65, respectively, while the other 18 isolates (35.3%) were defined as other STs. CC23 consisted of only K1 strains, while CC65 included only K2 strains. All non-K1/K2 strains were classified as STs other than CC23 and CC65. Approximately 70.6% (36/51) of KLA isolates exhibited an HV phenotype. Both K1 and K2 isolates presented significantly higher prevalence of the pLVPK-derived loci than non-K1/K2 isolates. The K1 isolates had a significantly higher prevalence of the kfu and allS genes than K2 and non-K1/K2 isolates, while the K2 isolates exhibited higher repA prevalence than K1 and non-K1/K2 isolates. The majority of KLA isolates belonged to CC23K1 and CC65K2, while other STs with non-K1/K2 capsular types have also been identified. The virulent factors exhibited diverse distribution among the different clones of KLA isolates.

Comparative study of MALDI-TOF MS and VITEK 2 in bacteria identification

BACKGROUND

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has recently been introduced in diagnostic microbiology laboratories for the identification of bacterial and yeast strains isolated from clinical samples. This study aimed to evaluate the accuracy of MALDI-TOF MS in clinical microbiology diagnosis by comparing it with commonly-used VITEK 2 or gene sequencing.

METHODS

The performances of MALDI-TOF MS and VITEK 2 were compared retrospectively for identifying routine isolates. Discrepancies were analyzed by gene sequencing analysis of the 16S genes.

RESULTS

For 1,025 isolates, classified as 55 species of 25 genera, 1,021 (99.60%) isolates were accurately identified at the genus level, and 957 (93.37%) isolates at the species level by using MALDI-TOF MS. A total of 949 (92.59%) isolates were completely matched by both methods. Both methods found 76 unmatched isolates among which one strain had no definite identification by MALDI-TOF MS and VITEK 2 respectively. However, MALDI-TOF MS made no errors at the genus level while VITEK 2 made 6 (0.58%) errors at the genus level. At the species level, the identification error rates for MALDI-TOF MS and VITEK 2 were 5.56% and 6.24%, respectively.

CONCLUSIONS

With a lower identification error rate, MALDI-TOF MS has better performance than VITEK 2 in identifying bacteria found routinely in the clinical laboratory. It is a quick and cost-effective technique, and has the potential to replace conventional phenotype methods in identifying common bacterial isolates in clinical microbiology laboratories.

A 12-week subchronic intramuscular toxicity study of risperidone-loaded microspheres in rats

Long-acting injectable formulations of antipsychotics have been an important treatment option to increase the compliance of the patient with schizophrenia by monitoring drug administration and identifying medication noncompliance and to improve the long-term management of schizophrenia. Risperidone, a serotoninergic 5-HT2 and dopaminergic D2 receptor antagonist, was developed to be a long-acting sustained-release formulation for the treatment of schizophrenia. In this study, 12-week subchronic toxicity study of risperidone-loaded microspheres (RMs) in rats by intramuscular injection with an 8-week recovery phase was carried out to investigate the potential subchronic toxicity of a novel long-acting sustained-release formulation. The results indicated that the dosage of 10-90 mg/kg of RM for 2 weeks did not cause treatment-related mortality. The main drug-related findings were contributed to the dopamine D2 receptor and α1-adrenoceptor antagonism of risperidone such as elevation of serum and pituitary prolactin levels and ptosis and changes in reproductive system (uterus, ovary, vagina, mammary gland, testis, seminal vesicle, epididymis, and prostate). In addition, foreign body granuloma in muscle at injection sites caused by poly-lactide-co-glycolide was observed. At the end of the recovery phase, these changes mostly returned to normal. The results indicated that RM had a good safety profile in rats.

Surface characterization and osteoblast response to a functionally graded hydroxyapatite/fluoro-hydroxyapatite/titanium oxide coating on titanium surface by sol-gel method

OBJECTIVES

To improve efficacy of current titanium and its alloys, in bioactivity and speed of osseointegration, of orthopaedic implants.

MATERIALS AND METHODS

A novel triple-layered functional graded coating, consisting of a porous hydroxyapatite (HA) outermost layer, fluoro-HA (FHA) intermediate layer and titanium oxide (TiO2 ) innermost layer, was created on a titanium substrate by a multistep sol-gel method. X-ray diffraction analysis showed TiO2 anatase and apatite crystallization in the coating.

RESULTS

Morphological analysis performed by scanning electron microscopy showed excellent bonding between coating and substrate, with a thickness of ~2 μm. Scratch testing found favourable adhesion strength of the composite coating. In addition, optical microscope images suggested good biocompatibility. Considering thet in vitro cell response, osteoblasts on the coating exhibited higher cell proliferation and ALP activity compared to pure titanium and HA coating, and demonstrated excellent coating bioactivity.

CONCLUSIONS

Current results indicated that the novel TiO2 /FHA/HA coating has promising clinical applications in orthopaedic and dental implantation.