[Clinical value of multiparameteric quantitative ultrasound for assessing high-risk steatohepatitis].

Objective: To investigate the clinical value of multiparameteric quantitative ultrasound combined with a non-invasive prediction model for assessing high-risk steatohepatitis. Methods: One hundred and ninety-four cases with metabolic-associated fatty liver disease (MAFLD) who underwent liver biopsy in Huashan Hospital, Fudan University, from June 2021 to September 2022 were selected. Shear wave elastography (SWE), shear wave dispersion (SWD) imaging, and attenuation imaging (ATI) examinations were conducted in all patients before biopsy. High-risk steatohepatitis was defined as a total activity score of ≥4 in patients with steatohepatitis, hepatocellular ballooning, and liver lobular inflammation based on pathological hepatic steatosis, inflammatory activity, and fibrosis scoring system (SAF), and fibrosis stage≥F2. Binary logistic regression analysis was used to identify the factors influencing high-risk steatohepatitis. A predictive model for diagnosing high-risk steatohepatitis was constructed using R language. The DeLong test was used to compare the area under the curve between groups. Measurement data was compared between groups using the t-test or rank-sum test, and count data were compared between groups using the χ2 test. Results: There were 46 cases (23.7%) with high-risk steatohepatitis. The quantitative ultrasound parameters included elastic modulus (OR=2.958, 95%CI: 1.889-4.883, P<0.001), dispersion coefficient (OR=1.786, 95%CI: 1.424-2.292, P<0.001) and attenuation coefficient (OR=42.642, 95%CI: 3.463-640.451, P=0.004). Serological indexes of fasting blood glucose (OR=1.196, 95%CI: 1.048-1.392, P=0.011), alanine aminotransferase (OR=1.012, 95%CI: 1.006-1.019, P<0.001), aspartate aminotransferase (OR=1.027, 95%CI: 1.014-1.042, P<0.001), γ-glutamyl transferase (OR=1.008, 95%CI: 1.001-1.017, P=0.041) and HDL cholesterol (OR=0.087, 95%CI: 0.016-0.404, P=0.003) were the factors influencing its progression. The AUCs of elastic modulus, dispersion coefficient, attenuation coefficient, multiparametric ultrasound model, serological index model, and ultrasound combined with serology model for the diagnosis of high-risk steatohepatitis were 0.764, 0.758, 0.634, 0.786, 0.773 and 0.825, respectively. The results of the DeLong test showed that the ultrasound combined with the serological model was significantly better than the serological index model and the elastic modulus, dispersion coefficient, and attenuation coefficient alone (P=0.024, 0.027, 0.038 and <0.001). Conclusion: The combination of multiparametric quantitative ultrasound is helpful for the non-invasive diagnosis of high-risk steatohepatitis and possesses great clinical significance.

[Clinical outcomes of allogeneic hematopoietic stem cell transplantation from matched sibling donor for myelofibrosis].

Objective: To evaluate the efficacy and safety of matched sibling donor allogeneic hematopoietic stem cell transplantation (allo-HSCT) for the treatment of myelofibrosis (MF). Methods: In this case series, the clinical data of 18 patients with MF who received allo-HSCT in the Department of Hematology, Peking University People's Hospital from December 2008 to December 2023 were retrospectively studied. Kaplan-Meier survival analysis and competitive risk model were used to evaluate the probabilities of 3-year overall survival (OS), disease-free survival (DFS), cumulative incidence of relapse (CIR), and transplant related mortality (TRM). The transplant related complications were also analyzed. Results: Among the 18 patients included, there were 12 males and 6 females, with a median age of 50 (range: 28-64) years. All 18 patients achieved neutrophil engraftment, and the time of neutrophil engraftment [M (Q1, Q3)] was 16.0 (11.8, 18.0) days. Twelve patients achieved platelet engraftment, and the platelet engraftment time was 21.0 (16.2, 43.2) days. Six patients had grade Ⅱ to Ⅳ acute graft-versus-host disease (GVHD), and six patients had chronic GVHD. The 3-year OS rate and DFS rate after transplantation were 62.2% and 52.2%, respectively. The 3-year CIR and TRM were 29.7% and 24.6%, respectively. Four patients died during follow-up, with the main cause of death being infections. Conclusion: Matched sibling allo-HSCT is a feasible option for the treatment of MF.

[The present and future of haploidentical hematopoietic stem cell transplantation in China].

The lack of donors is the biggest obstacle to the widespread use of hematopoietic stem cell transplantation. The establishment and improvement of new transplantation schemes have made haploid hematopoietic stem cell transplantation a clinical routine, benefiting a large number of patients with hematological diseases. Haploid donors have become the most important source of donors for allogeneic hematopoietic stem cell transplantation in China. This article focuses on the current situation and future development trends of haploid hematopoietic stem cell transplantation in China, in order to increase the understanding of clinical doctors on haploid hematopoietic stem cell transplantation.

[Rituximab based treatment in pediatric Epsstain Bar Virus associated lymphocyte proliferative diseases after aplastic anemia with haplo-identical transplantation:a prospective single centre study].

Epstein-Barr virus (EBV) associated post-transplant lymphoproliferative disorders (PTLD) are one of the most severe complications after hematopoietic stem cell transplantation (HSCT). This study includes 31 cases of aplastic anemia (AA) patients who developed PTLD after haploidentical transplantation, summarizing their clinical characteristics and categorizing them into either rituximab monotherapy group or combination therapy group based on whether their condition improved by 1 log after a single dose of rituximab. The incidence of PTLD after HSCT in children with AA was 10.16%, and the incidence of PTLD in patients with age >10 years was significantly increased (χ(2)=11.336, P=0.010). Of the 31 patients, 27 were clinically diagnosed and 4 were pathologically confirmed. Finally, 15 patients were classified into the rituximab treatment group and 15 patients into the combination treatment groups. Finally three patients died, and the 2-year overall survival rate was (89.7±5.6) %. Standard pre-treatment protocols and EBV reactivation are risk factors affecting the prognosis of PTLD. There was no statistically significant difference in the impact of the two treatment schemes on prognosis.

[Clinical features and prognosis of hepatosplenic candidiasis in patients with hematopathy].

Hepatosplenic candidiasis (HSC) is a rare type of candidiasis that can occur in patients with hematologic malignancies, hematopoietic stem cell transplantation. At present, there is still a lack of studies on HSC in patients with hematologic disorders. Based on The Chinese Guidelines for the Diagnosis and Treatment of Invasive Fungal Disease in Patients with Hematological Disorders and Cancers (the 6th revision), We retrospectively analyzed the clinical characteristics and prognosis of patients with HSC treated in Peking University Institute of Hematology from 2008 to 2022. Finally, eighteen patients were included, with 1 (5.6%) proven, 2 (11.1%) probable, and 15 (83.3%) possible HSC. Among them, 3 (16.7%) patients occurred after haploid hematopoietic stem cell transplantation and 15 (83.3%) patients occurred after chemotherapy. 6 (33.3%) patients had positive blood cultures, including 4 cases of Candida tropicalis and 2 cases of Candida albicans. At 4 weeks of antifungal therapy, 10 (58.8%) patients achieved partial response (PR), At 8 weeks, 1 (6.3%) patients achieved complete response and 10 (62.5%) patients achieved PR. At 6 months after diagnosis, 3 (16.7%) patients died of hematopoietic recurrence, and none of them died of HSC. As a rare fungal infection disease, HSC has a low positive rate of microbiological and histological examinations, a persistent treat cycle, and has difficulty in remission, reminding us of the need for vigilance in patients with hematopoietic disorders and persistent fever.

[Safety and efficacy analysis of a varicose vein sealant kit in the treatment of great saphenous vein dysfunction].

Objective: To investigate the safety and efficacy of a varicose vein sealant kit in the treatment of great saphenous vein dysfunction. Methods: It was a randomized controlled trial. A total of 180 patients with great saphenous vein dysfunction were enrolled prospectively, and scheduled for surgical treatment in 9 hospitals, including the Second Affiliated Hospital of Naval Medical University, Shanghai Oriental Hospital Affiliated to Tongji University, Xuanwu Hospital Capital Medical University, the First Hospital of Hebei Medical University, Ganzhou People's Hospital, Shanxi Bethune Hospital, the Second Affiliated Hospital of Zhejiang University School of Medicine, the Fourth Affiliated Hospital of Zhejiang University School of Medicine, and Zhongshan Hospital Affiliated to Xiamen University, from June to October 2022. Using a random number table method, the subjects were divided into an experimental group and a control group, with 90 cases in each group. The patients of experimental group received treatment with varicose vein sealant kit, while the patients of control group received radiofrequency ablation. The main outcome measure was the complete closure rate of the great saphenous vein in both groups of patients 3 months after surgery. The secondary outcome measures were the complete closure rate of the great saphenous vein in both groups of patients immediately after surgery and 6 months after surgery, the operation time for closing the main trunk of the great saphenous vein, pain score, venous clinical severity score (VCSS), Aberdeen varicose veins questionnaire (AVVQ) at different times before and after surgery, and the incidence of complications in both groups of patients. The non inferiority threshold for the two treatment methods is set at "-10.00%". Results: A total of 177 patients were ultimately enrolled. There were 89 cases in the experimental group, including 38 males and 51 females, with a median age [M (Q1, Q3)] of 59.7(49.6, 66.7) years, and 88 cases in the control group, including 30 males and 58 females, with a median age of 57.2(46.9, 65.9) years. A total of 174 patients completed a 3-month follow-up, and 167 patients completed a 6-month follow-up. The closure time of the main saphenous vein in the experimental group was (22.1±11.1) min, which was longer than the control group, which was (18.7±9.8) min (P=0.031). The complete closure rate of the great saphenous vein immediately after surgery in both the experimental group and the control group was 100%. The complete closure rates of the great saphenous vein at 3 months after surgery were 98.8% (85/86) and 98.9% (87/88), respectively. The lower limit of the 95%CI for the difference between the two groups was -3.19%, which was greater than the non-inferiority threshold of -10.00% (non-inferiority P<0.001). The complete closure rates of the great saphenous vein at 6 months after surgery were 97.6% (81/83) and 100% (84/84), the lower limit of the 95%CI for the difference between the two groups was -5.71%, which was greater than the non-inferiority threshold of -10.00% (non-inferiority P<0.001). The immediate pain scores after complete anesthesia awakening of the experimental group and the control group were both 1.0 (0, 2.0), with no statistically significant difference (P=0.365). The incidence of bruising in the experimental group and the control group one week after surgery was 61.2% (52/85) and 67.1% (57/85), respectively, with no statistically significant difference (P=0.181). There was no statistically significant difference in VCSS and AVVQ scores between groups before surgery and at 1, 3, and 6 months after surgery (all P>0.05). There was no statistically significant difference in the incidence of complications such as deep vein thrombosis, phlebitis, pain, and subcutaneous hematoma in the lower limbs 3 months after surgery (all P>0.05). Conclusion: The varicose vein sealant kit is safe and effective in treating great saphenous vein dysfunction, and can achieve a complete closure rate of great saphenous vein that is not inferior to traditional radiofrequency ablation.

[Causes and characteristics of pre-engraftment mortality after allogeneic hematopoietic stem cell transplantation].

Objective: To analyze the causes and demographic characteristics of pre-engraftment mortality in patients who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) and investigate the risk factors and measures for preventing pre-engraftment mortality. Methods: A retrospective case analysis, involving a total of 7 427 patients who underwent allo-HSCT at Peking University People's Hospital between January 2016 and July 2023, was conducted. Results: Among the 7 427 patients who underwent allo-HSCT, 56 cases (0.75% ) experienced pre-engraftment mortality. The median time to death for these 56 patients was +7 (-3 to +38) days after stem cell infusion. The median times to death for patients with acute leukemia (AL), severe aplastic anemia (SAA), and myelodysplastic syndrome (MDS) were +11 (-1 to +38), +3 (-1 to +34), and +16 (-1 to +38) days, respectively (P=0.013). The main causes of pre-engraftment mortality were infection (39.3% ), cardiac toxicity (28.6% ), and intracranial hemorrhage (26.8% ). Infection was the most common cause of pre-engraftment mortality in patients with AL and MDS (55.0% and 60.0% ), whereas cardiac toxicity was predominantly observed in patients with SAA (71.4% ), with no cases in patients with AL and only one case in patients with MDS. Among patients who died from intracranial hemorrhage, 53.3% had severe infections. The median times to death for infection, cardiac toxicity, and intracranial hemorrhage was +11 (-1 to +38), +2.5 (-1 to +17), and +8 (-3 to +37) days, respectively (P<0.001) . Conclusions: Infection is the primary cause of pre-engraftment mortality in allo-HSCT, and severe cardiac toxicity leading to pre-engraftment mortality should be closely monitored in patients with SAA.

[Clinical characteristics of human parvovirus B19 infection after allogeneic stem cell transplantation].

Human parvovirus B19 (HPVB19) belongs to Parvoviridae, a genus of erythrovirus, and has been associated with various human diseases, and HPVB19 infection is one of the most important causes of refractory anemia after allogeneic hematopoietic stem cell transplantation (allo-HSCT). This study retrospectively analyzed 24 patients with HSCT combined with HPVB19 infection to collate and summarize the clinical presentation, treatment, and regression of patients with combined HPVB19 infection after allo-HSCT and provide experience in the management of HPVB19 infection after allo-HSCT. The median age of the patients with HPVB19 infection was 25 years, and the median time of infection occurrence was +107 days after transplantation, and 22 (91.7% ) had anemia with a median hemoglobin (HGB) level of 77.5 (46-149) g/L, and 13 (54.2% ) had new-onset anemia or persistent decline in HGB. The median length of hospital stay was 19 days. Among patients with new-onset anemia or persistent decline in HGB, the mean increase in HGB after treatment with intravenous immunoglobulin and/or antiviral therapy was 15.69 g/L, and treatment was effective in 10 (76.92% ) patients. HPVB19 infection should be alerted to the development of refractory anemia after HSCT; despite the lack of specific treatment, the overall prognosis of HPVB19-infected patients is good.

[The impact of donor human leukocyte antigen-Bw4 allele on natural killer cell reconstitution and transplant-related mortality in haploidentical transplantation].

Objective: To investigate the impact of donor human leukocyte antigen (HLA) -Bw4 expression on natural killer (NK) cell reconstitution and transplant outcomes in recipients undergoing haploidentical hematopoietic stem cell transplantation (HSCT) from maternal or related donors without ex vivo T-cell depletion. Methods: This study prospectively enrolled 32 patients who received T-replete haploidentical HSCT from maternal or collateral donors (cohort 1) to evaluate the facilitating effect of donor HLA-Bw4 expression on NK cell reconstitution. Furthermore, a retrospective analysis was conducted on 278 patients who underwent T-replete haploidentical HSCT from maternal or collateral donors (cohort 2) to analyze the impact of donor HLA-Bw4 expression on HSCT outcomes. Thus, a comparison was made between the effects of donor HLA-Bw4 expression on HSCT outcomes in patients receiving or not receiving post-transplant cyclophosphamide (PT-Cy) conditioning. Results: Donors expressing HLA-Bw4 alleles facilitated NK cell reconstitution and functional recovery, which remained unaffected by PT-Cy. Donors with HLA-Bw4 expression were associated with reduced transplant-related mortality (TRM), particularly mortality related to infections. The use of PT-Cy did not impact the ability of donor HLA-Bw4 to decrease TRM. Conclusion: In haploidentical HSCT from maternal or related donors without ex vivo T-cell depletion, the presence of donor HLA-Bw4 expression promotes rapid NK cell reconstitution and functional recovery and is significantly associated with lower TRM, especially infection-related mortality. These findings underscore the clinical significance of donor HLA-Bw4 expression in patients who underwent HSCT. Hence, the consideration of donor HLA-Bw4 in recipient selection and HSCT strategies holds important clinical implications.

[Progress of allogeneic hematopoietic stem cell transplantation in KMT2A-rearranged acute leukemia].

KMT2A (lysine methyltransferase 2A) -rearranged acute leukemia is a class of leukemia with unique biological characteristics with moderate or poor prognosis. In recent years, allogeneic hematopoietic stem cell transplantation (allo-HSCT) has been increasingly indicated for patients with KMT2A-rearranged acute leukemia. By reviewing the clinical studies of allo-HSCT in KMT2A-rearranged acute leukemia, the efficacy of allo-HSCT in children and adults with KMT2A-rearranged acute myeloid leukemia and acute lymphoblastic leukemia was assessed, the factors affecting the prognosis of allo-HSCT were summarized, and the methods that may improve the outcomes of allo-HSCT were explored.

[The 507th case: hemolytic anemia, parvovirus B19, and multiple organ dysfunction].

A 19-year-old male patient with high-risk acute B-cell lymphoblastic leukemia received haploidentical stem cell transplantation. He developed anemia repeatedly and parvovirus B19 nucleic acid was positive in blood plasma. The patient was diagnosed with cold agglutinin syndrome and multiple organ dysfunction including respiratory failure and hepatitis. In the conflict between viral infection and the treatment of cold agglutinin syndrome, we provided supportive treatment, complement inhibitors to control hemolysis, and antiviral therapy. After timely glucocorticoid and immunosuppressant therapy, the patient had achieved a good response.

[The effect of glucose-6-phosphate dehydrogenase deficiency on allogeneic hematopoietic stem cell transplantation in patients with hematological disorders].

Objectives: To determine the effect of glucose-6-phosphate-dehydrogenase (G6PD) deficiency on patients' complications and prognosis following allogeneic stem cell hematopoietic transplantation (allo-HSCT) . Methods: 7 patients with G6PD deficiency (study group) who underwent allo-HSCT at Peking University People's Hospital from March 2015 to January 2021 were selected as the study group, and thirty-five patients who underwent allo-HSCT during the same period but did not have G6PD deficiency were randomly selected as the control group in a 1∶5 ratio. Gender, age, underlying diseases, and donors were balanced between the two groups. Collect clinical data from two patient groups and perform a retrospective nested case-control study. Results: The study group consisted of six male patients and one female patient, with a median age of 37 (range, 2-45) years old. The underlying hematologic diseases included acute myeloid leukemia (n=3), acute lymphocytic leukemia (n=2), and severe aplastic anemia (n=2). All 7 G6PD deficiency patients achieved engraftment of neutrophils within 28 days of allo-HSCT, while the engraftment rate of neutrophils was 94.5% in the control group. The median days of platelet engraftment were 21 (6-64) d and 14 (7-70) d (P=0.113). The incidence rates of secondary poor graft function in the study group and control group were 42.9% (3/7) and 8.6% (3/35), respectively (P=0.036). The CMV infection rates were 71.4% (5/7) and 31.4% (11/35), respectively (P=0.049). The incidence rates of hemorrhagic cystitis were 57.1% (4/7) and 8.6% (3/35), respectively (P=0.005), while the bacterial infection rates were 100% (7/7) and 77.1% (27/35), respectively (P=0.070). The infection rates of EBV were 14.3% (1/7) and 14.3% (5/35), respectively (P=1.000), while the incidence of fungal infection was 14.3% (1/7) and 25.7% (9/35), respectively (P=0.497). The rates of post-transplant lymphoproliferative disease (PTLD) were 0% and 5.7%, respectively (P=0.387) . Conclusions: The findings of this study indicate that blood disease patients with G6PD deficiency can tolerate conventional allo-HSCT pretreatment regimens, and granulocytes and platelets can be implanted successfully. However, after transplantation, patients should exercise caution to avoid viral infection, complications of hemorrhagic cystitis, and secondary poor graft function.

[Clinical features and risk factors for invasive fungal sinusitis after allogeneic hematopoietic stem cell transplantation].

Objective: To analyze the clinical characteristics and outcomes of patients with invasive fungal sinusitis (invasive fungal rhinosinusitis, IFR) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and explored the risk factors for IFR after allo-HSCT. Methods: Nineteen patients with IFR after allo-HSCT at Peking University People's Hospital from January 2012 to December 2021 were selected as the study group, and 95 patients without IFR after allo-HSCT during this period were randomly selected as the control group (1:5 ratio) . Results: Nineteen patients, including 10 males and 9 females, had IFR after allo-HSCT. The median age was 36 (10-59) years. The median IFR onset time was 68 (9-880) days after allo-HSCT. There were seven patients with acute myeloid leukemia, five with acute lymphoblastic leukemia, two with myelodysplastic syndrome, two with chronic myeloid leukemia, one with acute mixed-cell leukemia, one with multiple myeloma, and one with T-lymphoblastic lymph node tumor. There were 13 confirmed cases and 6 clinically diagnosed cases. The responsible fungus was Mucor in two cases, Rhizopus in four, Aspergillus in four, and Candida in three. Five patients received combined treatment comprising amphotericin B and posaconazole, one patient received combined treatment comprising voriconazole and posaconazole, nine patients received voriconazole, and four patients received amphotericin B. In addition to antifungal treatment, 10 patients underwent surgery. After antifungal treatment and surgery, 15 patients achieved a response, including 13 patients with a complete response and 2 patients with a partial response. Multivariate analysis revealed that neutropenia before transplantation (P=0.021) , hemorrhagic cystitis after transplantation (P=0.012) , delayed platelet engraftment (P=0.008) , and lower transplant mononuclear cell count (P=0.012) were independent risk factors for IFR after allo-HSCT. The 5-year overall survival rates in the IFR and control groups after transplantation were 29.00%±0.12% and 91.00%±0.03%, respectively (P<0.01) . Conclusion: Although IFR is rare, it is associated with poor outcomes in patients undergoing allo-HSCT. The combination of antifungal treatment and surgery might be effective.

[Effect of sirolimus combined with anti-CD20 monoclonal antibody desensitization on the prognosis of patients underwent haploidentical stem cell transplantation].

Objective: To investigate the effects of sirolimus combined with anti-CD20 monoclonal antibody desensitization on the prognosis of patients with haploidentical stem cell transplantation (haplo-SCT). Methods: Fifteen consecutive patients who received haplo-SCT and pre-transplant donor specific anti-human leukocyte antigen (HLA) antibody (DSA) positive [mean fluorescence intensity (MFI)≥2 000] in the Institute of Hematological Diseases from November 2021 to March 2023 were retrospectively recruited into the desensitized group. There were 4 males and 11 females, with a median age [M(Q1, Q3)] of 48 (37, 59) years. All patients were desensitized with sirolimus combined with anti-CD20 monoclonal antibody. The non-desensitized group included 29 patients with haplo-SCT who had not received desensitization treatment from August 2012 to June 2016. There were 12 males and 17 females with a median age of 42 (26, 50) years. Up to October 1, 2023, the median follow-up time was 13 (9, 18) months in the study group and 23 (14, 29) months in the control group. The changes of MFI before and after desensitization treatment and the prognosis of patients in the desensitized group were compared, including the incidence of primary implantation failure (pGF), neutrophil implantation time, platelet implantation time, grade Ⅱ-Ⅳ acute graft-versus-host disease (GVHD) and chronic GVHD incidence, non-recurrence related mortality, event-free survival rate, disease-free survival rate and overall survival rate. The survival curve was drawn by Kaplan-Meier method, and the survival rate between groups was compared with Log-rank test. Results: After desensitization treatment, the level of DSA MFI in the desensitized group decreased from 8 879 (7 544, 11 495) to 3 781 (1 638, 4 165) after desensitization treatment (P<0.01). All of the patients achieved hematopoietic recovery, and the median time for neutrophil and platelet engraftment were 14 (11, 15) and 20 (18, 25) days, respectively. The incidence of pGF in the desensitized group was 0, which was lower than that in the non-desensitized group (34.5%, 10/29) (P=0.011). The expected 1-year disease-free survival rate and overall survival rate in the desensitized group were 100% (15/15) and 100% (15/15) respectively, while those in the non-desensitized group were 75.9% (22/29) and 75.9% (22/29) respectively, the difference was not statistically significant (both P>0.05). The one-year event-free survival rate in the desensitized group was expected to be 100% (15/15), which was higher than that in the non-desensitized group (51.3%, 15/29) (P=0.002). Conclusion: Sirolimus combined with anti-CD20 monoclonal antibody desensitization therapy can reduce the DSA level of haplo-SCT recipients, promote hematopoietic engraftment after transplantation, and avoid the occurrence of pGF after transplantation.

[Role and related mechanisms of LiaSR two-component system in acid tolerance and biofilm formation of Streptococcus mutans].

Objective: To investigate the role and related mechanisms of the LiaSR two-component system in acid tolerance and biofilm formation abilities of Streptococcus mutans (Sm) 593. Methods: The growth curves of various Sm strains in pH=5.5 brian heart infusion (BHI) medium were analyzed. And colony forming unit (CFU) was also performed to evaluate the acid tolerance of Sm. Laurdan probe, H+-K+adenosine triphosphate (ATP)ase activity analysis kit, proton permeability assay and real-time fluorescence quantitative PCR (RT-qPCR) were conducted to detect the acid tolerant mechanisms of LiaSR two-component system in Sm. Crystal violet staining, CFU, SYTOX probe and anthrone-sulfuric method were used to analyze the properties and structures of the Sm biofilms. RT-qPCR was conducted to detect the expression levels of underlying regulated genes. Results: The growth of mutants in acidic BHI were inhibited (P<0.05). The acid tolerance of mutants significantly decreased compared to the wild-type strain (P<0.05). In mutants, the activity of H+-ATPase (917.06±59.53 and 469.53±47.65) were elevated by 7.22-folds and 3.70-folds compared to the wild-type strain (127.00±50.71) (P<0.001, P<0.001) and the encoded gene atpD (3.39±0.21 and 1.94±0.17) were also elevated by 3.39-folds and 1.94-folds compared to the wild-type strain (1.00±0.15) (P<0.001, P=0.001). The Laurdan generalized polarization of mutants (0.18±0.04 and 0.18±0.05) increased significantly compared to the wild-type strain (0.08±0.05) (P=0.006, P=0.003) and the expression levels of fabM gene were decreased in mutants (0.52±0.11 and 0.57±0.05) by 1/2 (P=0.014, P=0.022). In liaR deletion mutant, the reduced terminal pH (4.76±0.01) can also be observed (P<0.001). The total amount of the biofilms of three Sm didn't show significant differences (P>0.05). But the number of viable bacteria of mutants' biofilms were decreased [Sm 593: (12.00±2.80)×107 CFU/ml; Sm ΔliaS: (2.95±1.13)×107 CFU/ml; Sm ΔliaR: (7.25±1.60)×107 CFU/ml] (P=0.001, P=0.024). The extracellular DNA were increased by 18.00-folds and 6.50-folds in mutants' biofilms (128.73±15.65 and 46.38±5.52) compared to the wild-type strain (7.16±3.62) (P<0.001, P=0.003). Water-soluble exopolysaccharides could be found up-regulated in liaS deletion mutant [(138.73±10.12) µg/ml] (P=0.003) along with the expression level of gtfC gene (1.65±0.39) (P=0.014). The expression level of gtfD were elevated by 47.43-folds and 16.90-folds in mutants (P<0.001, P=0.010). Conclusions: The LiaSR two-component system can promote the expression of fabM gene and increase the fluidity of Sm which contributes to acid tolerance. The LiaR can also decrease the proton permeability and restrict the entrance of H+. The LiaSR two-component system can negatively regulate the production of the extracellular matrix in Sm biofilm.

[Clinical analysis of sirolimus as an alternative GVHD prophylaxis for patients with kidney injury undergoing allo-HSCT].

Objective: To explore the feasibility of sirolimus as an alternative graft versus host disease (GVHD) prophylaxis in patients with kidney injury after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Methods: Retrospective case series study. Medical records of 11 patients in Peking University People's Hospital from 1 August 2008 to 31 October 2022, who received sirolimus instead of cyclosporine to prevent GVHD, due to renal insufficiency after allo-HSCT, were analyzed retrospectively. Incidence of GVHD, infection, and transplant-associated thrombotic microangiopathy (TA-TMA), as well as renal function, were evaluated. Results: Among the 11 patients who received sirolimus, 6 were treated with haploidentical donor HSCT, and 5 were treated using matched sibling donor HSCT. The median (range) time of sirolimus administration was 30 (7-167) days after allo-HSCT, and the median (range) sirolimus course duration was 52 (9-120) days. During sirolimus treatment, 1 case did not undergo combined treatment with other prophylactic drugs, 3 cases received combined mycophenolate mofetil (MMF), and 1 case underwent combined CD25 monoclonal antibody treatment, while 6 cases had combined therapy with both MMF and CD25 monoclonal antibody. Of the 11 patients, 2 developed Grade Ⅲ acute GVHD, 1 developed severe pneumonia and died, and 1 developed TA-TMA, while nine patients had normal or improved renal function. Median (range) follow-up time was 130 (54-819) days. Non-relapse mortality was observed in 1 patient. Relapse mortality was also observed in 1 patient. Conclusion: Sirolimus-based alternative GVHD prophylaxis is a potentially viable option for patients undergoing allo-HSCT who cannot tolerate cyclosporine, but its efficacy and safety require further optimization and verification in prospective studies.

[Prognostic analysis of patients with acute leukemia and central nervous system involvement undergoing allogeneic hematopoietic stem cell transplantation].

Objective: To investigate the potential of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in mitigating the adverse prognosis associated with central nervous system leukemia (CNSL) and to assess the significance of prophylactic intrathecal injection. Methods: A retrospective cohort analysis was conducted involving 30 patients with acute leukemia who had a history of CNSL who underwent allo-HSCT at Peking University People's Hospital between September 2012 and March 2018 (referred to as the CNSL-positive group). In addition, 90 patients with acute leukemia were selected from the same period who underwent allo-HSCT without a history of CNSL (referred to as the CNSL-negative group) and a rigorous 1∶3 matching was performed based on disease type, disease status, and transplantation type to form the control group. The prognosis between the two groups was compared using Kaplan-Meier analysis and the high-risk factors for CNSL relapse post-transplant were identified through Cox proportional-hazards model. Results: The median age of patients in the CNSL-negative group was significantly higher than that of patients in the CNSL-positive group (32 years vs. 24 years, P=0.014). No significant differences were observed in baseline data, including sex, disease type, disease status at transplantation, donor-recipient relationship, and human leukocyte antigen consistency between the two groups. The median follow-up time was 568 days (range: 21-1 852 days). The 4-year cumulative incidence of relapse (71.4%±20.9% vs. 29.3%±11.5%, P=0.005) and the cumulative incidence of CNSL post-transplant (33.6%±9.2% vs. 1.2%±1.2%, P<0.001) were significantly higher in the CNSL-positive group than in the CNSL-negative group. Furthermore, the 4-year leukemia-free survival rate in the CNSL-positive group was significantly lower than that in the CNSL-negative group (23.1%±17.0% vs. 71.5%±11.6%, P<0.001). However, no significant differences were observed in the 4-year cumulative transplant-related mortality and overall survival rates between the two groups (both P>0.05). Multivariate analysis revealed that a history of CNSL before transplantation (HR=25.050, 95%CI 3.072-204.300, P=0.003) was identified as high-risk factors for CNSL relapse post-transplant. Conversely, haploidentical transplantation was associated with a reduced risk of CNSL relapse post-transplant (HR=0.260, 95%CI 0.073-0.900, P=0.034). Within the CNSL-positive group, seven patients received prophylactic intrathecal therapy after transplantation, and their CNSL relapse rate was significantly lower than that of the 23 patients who did not receive intrathecal therapy after transplantation (0/7 vs. 9/23, P=0.048). Conclusions: Patients with a history of CNSL have a higher risk of relapse and experience poorer leukemia-free survival following transplantation. The use of prophylactic intrathecal injection shows promise in mitigating CNSL relapse rates, although further validation through prospective studies is necessary to substantiate these observations.