Objective: To establish a method for the genotyping of fetal M blood group antigen by extracting cell-free fetal DNA (cff-DNA) from maternal plasma, so as to guide the management of M antigen-negative pregnant women with IgG anti-M antibody during pregnancy. Methods: A realtime fluorescent quantitative PCR (realtime PCR) method was established. The specificity and sensitivity of the method were validated by dilution of genomic DNA. Subsequently, a total of 12 M antigen-negative pregnant women were enrolled. The cff-DNA was extracted from maternal plasma, and fetal M antigen genotyping was performed by realtime PCR. Fetuses were classified as M-positive or M-negative according to the presence or absence of amplification curve. The accuracy of the method was validated by comparing fetal M antigen genotyping results with the serological results using the cord or peripheral blood of the neonate at birth. Results: Among the 12 M antigen-negative pregnant women, anti-M was detected in five cases, of which four cases had IgG anti-M, and one case had fetal anemia. The results of fetal M antigen genotyping showed that 9 cases were M-positive (9/12, 75%) and 3 cases were M-negative (3/12, 25%). Serological results of blood samples collected after birth from four M-positive fetuses and one M-negative fetus were consistent with the genotyping results. Conclusion: We have, for the first time, established a non-invasive prenatal genotyping method for fetal M antigen using maternal plasma cff-DNA, and preliminarily demonstrated the feasibility of this method.

Objective: To conduct screening for rare blood types within important blood group systems for the Chinese population, such as Rh, Duffy, Kidd, P1Pk, Diego, and MNS, in the Guangzhou region, and to establish a corresponding rare blood type database and physical repository. Methods: The saline medium microplate method was used to screen blood donors with the ccDEE phenotype combined with either Jk(a-) or Jk(b-). The polybrene microplate method was employed to screen for donors with Fy(a-), s(-), Lu(b-), Di(b-), k(-), and p phenotypes. The urea lysis microplate method was applied to screen for the Jk(a-b-) phenotype. A high-resolution melting (HRM) curve method was established for screening some donors with the Di(b-) phenotype. Subsequently, expanded phenotyping of antigens in the Rh, Kidd, MNS, Duffy, P1Pk, Lewis, Kell, and Lutheran blood group systems was performed on identified rare blood type donors using monoclonal antibodies. The test results are entered into the Rare Blood Type Bank Management System of the Guangzhou Blood Center, enabling functions such as confirmation reminders and cryopreservation storage when the donor donates again. Red blood cells of rare blood types are processed into frozen red blood cells for long-term storage. Results: Among voluntary blood donors, 16 cases of the ccDEE combined with Jk(a-) phenotype were identified (0.221 7%, 16/7 216); 10 cases of the ccDEE combined with Jk(b-) phenotype (0.138 6%, 10/7 216); 78 cases of the Fy(a-) phenotype (0.169 5%, 78/46 012); 39 cases of the Lu(b-) phenotype (0.138 2%, 39/28 214); 31 cases of the s(-) phenotype (0.081 8%, 31/37 913); 22 cases of the Di(b-) phenotype (0.029 9%, 22/73 691); 30 cases of the Jk(a-b-) phenotype (0.010 1%, 30/298 250); and 1 case of the k(-) phenotype (0.001 3%, 1/77 382), which was further identified as KELnull phenotype (K0). No p phenotype donors were identified (0/88 528). A total of 228 units of frozen red blood cells were prepared. The screening results were compared and analyzed with rare blood type data from other regions. Conclusion: This study, through a combination of different screening methods, significantly improved the efficiency of rare blood type screening while remaining cost-effective. By conducting large-scale screening and performing data informatization processing, a database and physical repository of rare blood types in the Guangzhou region were successfully established. This provides a strong guarantee for the timely supply of blood to patients with difficult-to-match and rare blood types in the region, effectively enhances the level of transfusion safety in the region, and offers a practical paradigm for constructing a comprehensive blood transfusion support system.

Central serous chorioretinopathy(CSC)is a macular disease predominantly affecting young to middle-aged adults, characterized by serous retinal detachment in the posterior pole, leading to symptoms such as decreased central vision, visual distortion, and color changes. The disease has a certain degree of self-limitation but can recur. The pathogenesis is still uncertain and the treatment is controversial. Commonly used treatments include medication, retinal laser, photodynamic therapy(PDT)and vitreous anti-vascular endothelial growth factor(VEGF)therapy which have emerged in recent years, but the treatment of recurrent CSC is still tricky. The purpose of this article is to review the current therapeutic approaches regarding CSC, with a view to providing a reference for clinical treatment.

Objective:To evaluate the clinical efficacy, safety and treatment persistence of upadacitinib in Crohn's disease (CD) patients.Methods:The single-center retrospective cohort study was conducted. The patients with moderate-to-severe active CD initiating upadacitinib therapy from November 2023 to November 2024 in Nanjing Drum Tower Hospital were collected through searching the electronic medical records and paper-based patient databases. The primary outcome was the clinical remission rate at week 12. Secondary outcomes included the clinical response rate at week 12; clinical response and remission rates at weeks 4, 24 and 48; biomarker (fecal calprotectin or C-reactive protein) remission rates at all time points; as well as endoscopic remission and response rates, treatment persistence and safety evaluation.Results:A total of 44 CD patients were included, comprising 24 males (54.5%) and 20 females (45.5%). The median age was 33 (25, 40) years. The baseline Crohn's disease activity index (CDAI) score was 260.5 (225.9, 550.0) points. Patients had previously received a median of 2 (1, 2) biologic treatments. All 44 patients completed the 12-week induction therapy. With a median follow-up of 30.00 (16.25, 46.25) weeks, the clinical remission rate was 50.0% (22/44) at week 12. The clinical remission rate, clinical response rate, and biomarker remission rate were 52.3% (23/44), 88.6% (39/44) and 72.7% (32/44) respectively at week 4, and the clinical response rate and biomarker remission rate were 88.6% (39/44) and 77.2% (34/44) respectively at week 12. The clinical remission rates, clinical response rates and biomarker remission rates evolved to 43.3% (13/30), 86.7% (26/30) and 80.0% (24/30) at week 24, and further to 44.4% (4/9), 77.8% (7/9) and 77.8% (7/9) at week 48. During the follow-up period, 13 CD patients completing endoscopic evaluation, endoscopic remission and response rates were 30.8% and 23.1% respectively. CD-related surgery rate was 4.5% (2/44). Safety analysis demonstrated that the overall adverse events rate was 56.8% (25/44) including 7 patients with serious adverse events. A total of 8 patients discontinued treatment, among which 3 were due to primary loss of response, 1 due to secondary loss of response, 2 due to drug-related adverse events alone, and 2 due to concurrent primary loss of response and adverse events. The Kaplan-Meier curve for treatment persistence showed that among 39 CD patients who achieved clinical response at week 12, the continued treatment rates were 90.3% at week 12 and 85.3% at week 24 of follow-up. Two patients (5.6%) received dose escalation of upadacitinib, both of whom achieved clinical remission.Conclusion:Real-world research data demonstrate that upadacitinib exhibits significant clinical efficacy and a favorable safety profile in the treatment of moderate-to-severe active CD patients with prior biologic exposure, and no new unexpected adverse events are identified.

Carbapenem-resistant Enterobacteriaceae(CRE), one of the most urgent pathogens threatening human health worldwide, has posed a great challenge to clinical treatment. However, the imbalance between the lag in antibiotic research and development and the increase of CRE resistance has led to a "death threat" for patients infected with CRE, and it is urgent to explore new mechanisms of CRE resistance, which is closely related to the role of resistance genes, carbapenemases and efflux pumps. In addition, penicillin-binding protein, biofilms and iron carriers are expected to provide new research ideas to understand the drug resistance mechanism. The aim of this review is to summarize the mechanisms of CRE resistance and to provide new ideas for its treatment.

Carbapenem-resistant Enterobacteriaceae(CRE), one of the most urgent pathogens threatening human health worldwide, has posed a great challenge to clinical treatment. However, the imbalance between the lag in antibiotic research and development and the increase of CRE resistance has led to a "death threat" for patients infected with CRE, and it is urgent to explore new mechanisms of CRE resistance, which is closely related to the role of resistance genes, carbapenemases and efflux pumps. In addition, penicillin-binding protein, biofilms and iron carriers are expected to provide new research ideas to understand the drug resistance mechanism. The aim of this review is to summarize the mechanisms of CRE resistance and to provide new ideas for its treatment.

Objective:To evaluate the clinical efficacy, safety and treatment persistence of upadacitinib in Crohn's disease (CD) patients.Methods:The single-center retrospective cohort study was conducted. The patients with moderate-to-severe active CD initiating upadacitinib therapy from November 2023 to November 2024 in Nanjing Drum Tower Hospital were collected through searching the electronic medical records and paper-based patient databases. The primary outcome was the clinical remission rate at week 12. Secondary outcomes included the clinical response rate at week 12; clinical response and remission rates at weeks 4, 24 and 48; biomarker (fecal calprotectin or C-reactive protein) remission rates at all time points; as well as endoscopic remission and response rates, treatment persistence and safety evaluation.Results:A total of 44 CD patients were included, comprising 24 males (54.5%) and 20 females (45.5%). The median age was 33 (25, 40) years. The baseline Crohn's disease activity index (CDAI) score was 260.5 (225.9, 550.0) points. Patients had previously received a median of 2 (1, 2) biologic treatments. All 44 patients completed the 12-week induction therapy. With a median follow-up of 30.00 (16.25, 46.25) weeks, the clinical remission rate was 50.0% (22/44) at week 12. The clinical remission rate, clinical response rate, and biomarker remission rate were 52.3% (23/44), 88.6% (39/44) and 72.7% (32/44) respectively at week 4, and the clinical response rate and biomarker remission rate were 88.6% (39/44) and 77.2% (34/44) respectively at week 12. The clinical remission rates, clinical response rates and biomarker remission rates evolved to 43.3% (13/30), 86.7% (26/30) and 80.0% (24/30) at week 24, and further to 44.4% (4/9), 77.8% (7/9) and 77.8% (7/9) at week 48. During the follow-up period, 13 CD patients completing endoscopic evaluation, endoscopic remission and response rates were 30.8% and 23.1% respectively. CD-related surgery rate was 4.5% (2/44). Safety analysis demonstrated that the overall adverse events rate was 56.8% (25/44) including 7 patients with serious adverse events. A total of 8 patients discontinued treatment, among which 3 were due to primary loss of response, 1 due to secondary loss of response, 2 due to drug-related adverse events alone, and 2 due to concurrent primary loss of response and adverse events. The Kaplan-Meier curve for treatment persistence showed that among 39 CD patients who achieved clinical response at week 12, the continued treatment rates were 90.3% at week 12 and 85.3% at week 24 of follow-up. Two patients (5.6%) received dose escalation of upadacitinib, both of whom achieved clinical remission.Conclusion:Real-world research data demonstrate that upadacitinib exhibits significant clinical efficacy and a favorable safety profile in the treatment of moderate-to-severe active CD patients with prior biologic exposure, and no new unexpected adverse events are identified.

Objective To elucidate the prediction ability of monocyte monolayer assay(MMA)used in hemolytic dis-ease of fetus and newborn(HDFN)caused by IgG anti-M.Methods Plasma from eight pregnant women containing IgG an-ti-M were collected,and were divided into two groups(4 cases with HDFN,with severe clinical symptoms such as fetal hy-drops,and 4 cases without HDFN)according to the clinical outcomes.M antigen positive cells were sensitized with dithioth-reitol(DTT)treated plasma from eight pregnant women respectively.MMA was performed by coincubation with monocytes and sensitized M cells,along with negative and positive control set up.T-test was conducted to compare the difference in phagocytic efficiency between two groups.Results The phagocytic efficiency in group with HDFN were 15.37%,13.05%,9.17%and 24.50%respectively,with the mean value of 15.52%,while the group without HDFN were 8.74%,11.07%,5.12%and 6.23%respectively,with the mean value of 7.79%.There was no significant difference in phagocytic efficiency between two groups(P>0.05).The mean values of both groups were not significantly different from the negative control(P>0.05),but both were significantly lower than positive control(P<0.05).Conclusion The low phagocytic efficiency couldn't convince that the MMA is an effective predictor for the HDFN caused by IgG anti-M,indicating that another mech-anism might be responsible for it rather than monocyte phagocytosis.The assessment of the peak systolic velocity in middle cerebral artery of the fetal should be considered in the management for pregnant women who produce IgG anti-M to estimate the situation of fetal anemia.

Objective:To develop a genotyping method for the Junior blood type and report on a rare blood type with Jr(a-).Methods:Healthy O-type RhD+ volunteer donors of the Shenzhen Blood Center from January to May 2021 ( n=1 568) and a pedigree with difficult cross-matching ( n=3) were selected as the study subjects. Serological methods were used for proband′s blood type identification, unexpected antibody identification, and antibody titer determination. Polymerase chain reaction-sequence specific primer (PCR-SSP) method was used for typing the proband′s RHD gene. ABCG2 gene coding region sequencing and a PCR-SSP genotyping method were established for determining the genotypes of the proband and his family members and screening of Jra antigen-negative rare blood type among the 1 568 blood donors. Results:The proband′s ABO and RhD blood types were respectively determined as B and partial D (RHDDVI.3/RHD01N.01), Junior blood type Jra antigen was negative, and plasma had contained anti-D and anti-Jra. Sequencing of the ABCG2 gene revealed that the proband′s genotype was ABGG201N.01/ABGG201N.01 [homozygous c. 376C>T (p.Gln126X) variants], which is the most common Jr(a-) blood type allele in the Asian population. Screening of the voluntary blood donors has detected no Jr(a-) rare blood type. Statistical analysis of the heterozygotes suggested that the allelic frequency for ABCG2*01N.01 (c.376T) was 0.45%, and the frequency of Jr(a-) rare blood type with this molecular background was about 0.2‰. Conclusion:A very rare case of partial DVI.3 type and Jr(a-) rare blood type has been identified. And a method for identifying the Junior blood type through sequencing the coding regions of the ABCG2 gene and PCR-SSP has been established.

【Objective】 To identify the specificity of alloantibody against high-frequency antigens in one case suffering with severe hemolytic diseases of the fetus and newborn (HDFN) and to screen for matching blood for transfusion. 【Methods】 The HDFN test and the antibody serological identification tests in the mother were performed. Several common high frequency antigens of maternal red blood cells (RBCs) were determined. IgG subtype coated on the RBCs of the newborn was determined. The phagocytic efficiency of the antibody was tested using the monocyte phagocytosis of sensitized erythrocyte by flow cytometry in vitro. Sanger sequencing of DI gene was performed in the mother, father and mother’s brother. The diluted maternal plasma was used for large scale screening of matching blood using IAT in Coomb’s gel card. 【Results】 Di(b-) phenotype was identified in the mother of the newborn and anti-Di^b (titer: 512) related HDN was detected in the newborn. IgG1 and IgG2 subtypes of anti-Di^b were detected and the rate of monocyte phagocytosis was 88.83%(74.7/84.09). The compatible blood was not detected in the maternal relatives. Subsequently, the newborn received the matching RBCs of two Di(b-) donors identified from 5 520 blood donors and discharged from the hospital. We screened out 17 Di(b-) donors out of 51 334 blood donors, indicating that the distribution frequency of Di(b-) among blood donors in Guangzhou was about 0.033% (17/51 334). 【Conclusion】 By serology and molecular biology methods, the newborn was identified with HDFN caused by anti-Di^b, and an effective large-scale screening method for Di (b -) rare blood types was established to find matching blood, which supported the establishment of rare Di(b-) blood database.