Background Quartz dust cannot be degraded in the lungs, and inhalation of a large amount of quartz dust in the occupational production process will lead to the occurrence of pulmonary fibrosis, and then develop into silicosis. In recent years, studies have found that exosomes may be involved in the pathogenesis of fibrotic diseases by carrying microribonucleic acid (miRNA), but the mechanism of their actions in silicosis still needs to be studied. Objective To investigate the role of exosome-derived miRNA-21-5p/mothers against decapentaplegic homolog 7 (Smad7) in quartz dust-induced pulmonary fibrosis in rats. Methods Twenty-four healthy male SD rats were randomly divided into four groups (six rats in each group): control 4-week group, control 16-week group, quartz 4-week group, and quartz 16-week group. At the beginning of the experiment, 1 mL of quartz suspension (50 mg·mL⁻¹) and 1 mL of normal saline were injected into the trachea of rats in the quartz group and the control group, respectively, by means of one-time non-exposure intratracheal dust staining. Alveolar lavage was performed at the 4th and 16th weeks after dust staining, the exosomes in lavage solution were extracted by polyethylene glycol (PEG) precipitation, morphological identification was conducted by transmission electron microscopy (TEM), particle size of exosomes was detected by nano-tracking analysis (NTA), and the marker proteins CD9 and CD63 of exosomes were detected by Western blotting (WB). The expression of miRNA-21-5p in exosomes was determined by reverse transcription polymerase chain reaction (RT-PCR). The degree of lung tissue injury and fibrosis was observed by hematoxylin-eosin staining (HE) and Masson staining. The collagen content of lung tissue was detected by hydroxyproline (HYP) method. The expression of Smad7 protein in lung tissue was detected by WB. Results The results of pathological staining showed that compared with the control group, lung inflammatory cell infiltration, alveolar wall thickening, and collagen increase were observed after 4 weeks of dusting, and collagen deposition and silicon nodules appeared after 16 weeks of dusting. Compared with the control group, the expression level of HYP in the lung tissue of the quartz group was increased after 4 weeks and 16 weeks of dust staining (P<0.05). Transmission electron microscopy showed that exosomes were saucer-shaped, and the average particle size of exosomes was 95.8 nm by NTA. Positive expression of exosome marker proteins CD9 and CD81 was found by WB. Compared with the control group, the expression of exosome-derived miRNA-21-5p in alveolar lavage fluid in the quartz group increased in the 4th week and the 16th week (P<0.05), and the expression of Smad7 protein in lung tissue decreased (P<0.05). Conclusion Exosome-derived miRNA-21-5p and Smad7 may be involved in the mechanism of quartz dust-induced pulmonary fibrosis in rats.

Objective: To explore the effects of subchronic aluminum exposure on the level of N6-methyladenosine (m6A) methylation and the expression of N6-methyladenosine RNA binding protein 1 (YTHDF1) in the hippocampus of rats. Methods: Twenty-four healthy male SD rats were randomly divided into the control group (normal saline), the low dose group [10 μmol/kg Al(mal)3], the medium dose group [20 μmol/kg Al(mal)3] and the high dose group [40 μmol/kg Al(mal)3], with 6 rats in each group. The Al(mal)3 solution was administered via intraperitoneal injection on alternate days for 90 days. Escape latency, target quadrant dwell time and platform crossing times were tested to evaluate the learning and memory ability of the rats by the Morris water maze test after exposure. The brain tissue was weighted and the brain-to-body weight ratio was calculated after euthanasia. The level of m6A methylation and the expression of YTHDF1 were determined by enzyme-linked immunosorbent assay and western blot assay, respectively. Results: All rats survived during aluminum exposure period. The brain-to-body weight ratios of the control group and the low, medium and high dose groups were (0.46±0.06)%, (0.44±0.04)%, (0.49±0.06)% and (0.51±0.07)%, respectively, with no statistically significant differences (P>0.05). The escape latency of rats in the high dose group was longer than that in control and low group during the third to fifth day (both P>0.05). The escape latency of rats in all groups was shortened with the increase of training days (P<0.05). The target quadrant dwell time of rats in low, medium and high dose groups were lower than that in control group, and the platform crossing times of rats in high dose group were lower than that in control group (all P<0.05). The methylation level of m6A and expression level of YTHDF1 in hippocampus of rats in medium and high dose groups was higher than that in control group (both P<0.05). Conclusion The learning and memory impairment caused by subchronic aluminum exposure may be related to the increase of m6A methylation level and the decrease of YTHDF1 expression.

Objective: To investigate the current situation of stress ulcer prevention in patients with orthopedic joint replacement in our hospital and explore the necessity of preventing bleeding of peptic ulcer in patients with hip/knee replacement. Methods: The ca-ses of hip/knee replacement discharged from our hospital in September 2017 were retrospectively analyzed. The age and gender of the patients were analyzed. The underlying medical conditions, the related laboratory indices and the uses of stress ulcer prevention drugs, analgesic and anticoagulation drugs were statistically analyzed. Results: A total of 109 cases were collected including 40 cases of hip replacement and 69 cases of knee replacement. The median of age was 63. The use rate of non-steroidal analgesic drugs was 98. 16% , that of deep venous thrombosis prevention drugs was 95. 4% , and that of stress ulcer prevention drugs was 67. 9% . No patient suffered from gastrointestinal bleeding. Conclusion: The majority of patients undergoing hip /knee replacement are the elderly, and the knee replacement patients are older with more operation duration and more bleeding during the hip replacement. Nonsteroidal anti-inflamma-tory drugs and the drugs for preventing deep venous thrombosis are widely used during perioperative period. At present, it is still uncer-tain whether the population needs regular prevention of stress ulcers. However, the combination of aspirin and NSAID is a risk factor. The other high-risk factors, as well as the necessity of prevention medication, still need to be investigated in a larger scale.

When a conventional phase-encoding magnetic resonance spectrascopic imaging(MRSI) method is in use, the data acquisition is very time consuming and thus it is not well accepted in clinical settings. Echo planar spectroscopic imaging (EPSI) technology has been applied for rapid acquisition of MRSI data. It significantly reduces scan time by simultaneously encoding the spectral dimension and the spatial dimension. Reconstruction of EPSI data is sophisticated. For the t-dimension, data are non-uniformly sampled. Fast Fourier transform (FFT) is applied in odd echoes and even echoes respectively and then shift method is used to combine them together. For the kx dimension, the data are unevenly sampled and have to be interpolated onto a Cartesian grid before FFT is applied. For the phase-encoding dimension (ky), the Fourier transform can be readily done with FFT since the data are evenly spaced.
Algorithms ; Echo-Planar Imaging ; methods ; Image Processing, Computer-Assisted ; methods ; Magnetic Resonance Spectroscopy ; methods ; Signal Processing, Computer-Assisted

ObjectiveTo investigate the efficacy of haploidentical blood and marrow transplantation (haplo-BMT) in the treatment of advanced chronic myeloid leukemia (CML).MethodsFrom November 2002 to October 2007,35 patients with advanced CML received haplo-BMT.Eleven patients achieved the second chronic phase (CP2) after treatment with imatinib or chemotherapy or both before pre-conditioning,but there were 13 cases in accelerated phase (AP) and 11 patients in blast phase (BP) at the time of transplantation.By the last follow-up date October 31,2011,the median follow-up time among living patients was 67 months (range,49 to 100 months).ResultsThe cases of HLA-antigen mismatched between donors and recipients as 1,2,and 3 antigens were 1,12,and 22 respectively.The number of mean mononuclear cells and CD34+ cells was (7.19+ 1.37) × 108/kg and (2.54± 1.50) × 106/kg,respectively.All but one patient achieved durable hematopoietic reconstitution. Hyperacute graft-versus-host disease (GVHD) occurred in 28.6％ (10/35) patients.The cumulative incidence of grade Ⅱ to Ⅳ acute GVHD was 48％.Among 27 patients who survived longer than 100 days after transplant,16 (60 ％) had chronic GVHD.Fiveyear overall survival (OS) rate was 46.2％ and 45.5％ in CML-AP and BP (P =0.97),respectively.Five-year probability of OS rate was 81.8％,30.8％ and 27.3％ in patients with CML-CP2,CML-AP and BP at transplant,respectively.The OS of CML-CP2 was significantly higher than CML-AP and BP at transplant (P＜0.01 ).ConclusionHaplo-BMT is a feasible therapeutic mean for patients with advanced CML who have no matched donors available.It is better to perform haplo-BMT at CML-CP2 other than CML-AP or BP.

Objective: To analyze the clinical characteristics and prognosis of 34 cases of acute myeloid leukemia (AML) with FLT3 internal tandem duplication (FLT3-ITD) and MLL gene rearrangement. Methods: The clinical data of 34 AML patients with FLT3-ITD and MLL gene rearrangement was compared and analyzed for the therapeutic efficacy, prognostic factors when treated with chemotherapy, chemotherapy combined with targeted therapy or allogenic hematopoietic stem cell transplantation (allo-HSCT). Results: Of the thirty-four cases with median age 41 (4-71) years old, 63.6% presented with white blood cells (WBC) greater than 30×10⁹/L, 39.4% greater than 50 × 10⁹/L respectively on admission. M₅ (35.3%) made up the highest proportion. The cytogenetic abnormality reached 61.8%, of which the complex cytogenetic abnormality accounted for 11.8%. Eleven patients (32.35%) had both FLT3-ITD and MLL gene abnormalities. In addition to FLT3 and MLL abnormalities, 23 patients (67.6%) had one or more other gene abnormalities (multiple gene abnormalities). Of the 34 cases, 29.4% patients went into complete remission (CR) after two courses of chemotherapy. 20.6% (7 patients) went into CR after 3 or more courses of chemotherapy. The rate of early relapse in the CR group was 52.9%. Patients with WBC>50×10⁹/L or multiple gene abnormalities had a lower remission rate (7.7%, 5.4%) after two courses of chemotherapy. CR rate for the patients with more than three gene abnormalities was 0. The total 2-year overall survival (OS) in the 34 patients was 28.8% (95% CI 13.5%-46.0%) and the disease-free survival (DFS) was 27.1% (95% CI 12.5%-44.0%). Of the 18 patients treated with chemotherapy alone or chemotherapy combined with targeted therapy, 17 cases died within 2 years and 1 lost follow-up after giving up treatment. For the 16 patients received allo-HSCT, the 3-year OS was 43.4% (95% CI 13.7%-70.4%) and DFS 42.7% (95% CI 13.4%-69.7%). Conclusion AML patients with FLT3-ITD and MLL gene rearrangement often presented with M₅, accompanied by hyperleukocytosis, cytogenetic or multiple gene abnormalities. Those patients were observed to have low response rate and high early relapse when treated with chemotherapy without allo-HSCT. Patients had multiple gene abnormalities may be an important poor prognostic factor. Allo-HSCT is an effective treatment which could significantly improve the prognosis and survival of AML patients with FLT3-ITD and MLL gene abnormalities.

Objective: To investigate the effect of minimal residual disease (MRD) monitoring by multiparameter flow cytometry (MFC) pre-conditioning on prognosis of acute myeloid leukemia in first complete remission (CR₁-AML) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) , and to explore the value of MRD monitoring by MFC in the prognosis evaluation on allo-HSCT in CR₁-AML. Methods: Between April 2012 and March 2015, consecutive 186 patients with CR₁-AML who underwent allo-HSCT were analyzed retrospectively. MRD in BM before conditioning was detected by eight-color MFC. Any level of residual disease was considered to be MRD positive. Results: ①Of 186 patients, MRD was negative in 151 patients, positive in 35 patients (<1% in 25 patients and 1% to 3% in 10 patients) . ② With the median follow up of 18 (5-41) months, two-year DFS was 80.0% (95%CI 68.5%-92.3%) . Univariate analysis showed that MRD positive patients had lower DFS[62.9% (95%CI 50.6%-75.2%) vs 88.9% (95%CI 76.6%-100.0%) , P<0.001], higher relapse[11.4% (95%CI 4.1%-29.0%) vs 3.3% (95% CI 0.6%-20.9%) , P=0.003] and higher NRM [25.7% (95% CI 8.1%-43.3%) vs 7.9% (95% CI 1.3%-26.5%) , P=0.001] after HSCT compared with that of MRD negative patients. Secondary AML showed lower DFS than primary AML [60.0% (95% CI 42.4%-76.6%) vs 86.0% (95% CI 68.4%-100.0%) , P=0.004]. ③Multivariate analysis indicated that MRD positive pre-HSCT was the independent risk factor on DFS [HR=4.565 (95%CI 2.918-9.482) , P<0.001], relapse [HR=5.854 (95%CI 1.538-22.288) , P=0.010] and NRM [HR=3.379 (95%CI 1.361-8.391) , P=0.009] after allo-HSCT in CR₁-AML. Conclusion MRD positive pre-conditioning was the only negative impact factor for patients with CR₁-AML after allo-HSCT. MRD by MFC can be used to assess the prognosis of CR₁-AML after allo-HSCT.

OBJECTIVETo evaluate the efficacy of HLA- haploidentical donor hematopoietic transplantation (Haplo- HSCT)for severe aplastic anemia (SAA)by compared with the same period of unrelated donor transplantation (UD- HSCT).

METHODSOf a cohort of 50 SAA patients between September 2012 and July 2014, 26 patients underwent UD- HSCT and 24 patients Haplo- HSCT.

RESULTSOS rate was 91.3% with a median follow-up of 9 (2-26)months. According to transplant type, there was no significant difference between UD- and Haplo-HSCT (96.1%vs 86.0%,P=0.30). 3 of 50 (6%)patients had primary engraft failure. Haplo- HSCT developed higher significantly incidence of Ⅱ- Ⅳ aGVHD (37.5%vs 3.83%,P=0.003)and cGVHD (37.5%vs 15.3%,P=0.030)than UD-HSCT. Haplo-HSCT also had significantly higher incidences of CMV viremia (78.2%vs 46.1%,P=0.005)and EBV viremia (43.1%vs 16.0%,P=0.040), respectively than UD-HSCT. But the incidences of hemorrhagic cystitis were similar between two transplant types (39.1%vs 23.0%,P=0.120).

CONCLUSIONThis study showed favorable outcome of Haplo-HSCT for SAA, which was comparable with UD-HSCT.

Objective: To investigate three different types of donor hematopoietic stem cell transplantation (HSCT) for intermediate and high-risk myelodysplastic syndrome (MDS) . Methods: Between August 2001 and May 2015, 167 consecutive patients with MDS in intermediate and high-risk who underwent allogeneic HSCT were analyzed retrospectively. Results: With the median follow up of 60 (12-177) months, The total 5-year DFS was 67.8% (95%CI 60.0%-75.6%) . Among three different types of donor, 5-year DFS rates were 68.0% (95%CI 54.1%-81.9%) in MSD-HSCT vs 77.4% (95%CI 62.1%-92.7%) in MUD-HSCT vs 64.0% (95% CI 52.4%-75.6%) in Haplo-HSCT (P=0.632) , respectively. Univariate analysis showed that median disease course before HSCT was the influencing factor of DFS (P=0.018) . Five-year relapse and TRM had no correlation with the above-mentioned factor. Conclusions Haplo-HSCT for intermediate and high-risk MDS achieved similar effect produced by MUD or MSD, Haplo-HSCT could be used as an important alternative donor. allo-HSCT must be performed on intermediate and high-risk MDS patients as early as possible after diagnosis.

Objective:To summarize the clinical manifestations, imaging characteristics, and diagnoses basis of adrenomyeloneuropathy (AMN).Methods:The clinical data of 3 patients with AMN, admitted to our hospital from November 2016 to April 2019, were retrospectively collected. The clinical manifestations, imaging features, and diagnostic process of these patients were analyzed.Results:Three young male patients had onset with gradual aggravation of unilateral or bilateral lower limb insufficiency. MR imaging showed symmetrical abnormal signals in brainstem in 2 patients, and atrophy of thoracic spinal cord in 1 patient. By target region capture sequencing, mutations in the ABCD1 gene were found in all 3 patients; 2 underwent pedigree validation; the remaining one patient and his mother had failed Sanger sequencing validation due to pseudogene interference, and elevated plasma level of very long chain fatty acid (VLCFA) was noted in this patient. Conclusions:AMN usually initiates in the adulthood with spastic paraplegia as onset. Symmetrical lesions in brainstem or atrophy of spinal cord can be manifested on MR imaging; some patients may be accompanied by adrenocortical insufficiency. The definite diagnosis mainly depends on genetic screening and determination of VLCFA level in the blood.