This study was aimed atanalyzing the epidemic characteristics of dengue fever in Ruili City atthe China-Myanmar bor-der in late 2023,to provide evidence for local dengue fever prevention and control measures.Adult Aedes mosquitoes were collected from Ruili City with a backpack type mosquito sucking machine in October of 2023.Serum samples frompatients with suspected den-gue were collected in acutephase,in November of 2023.Detection ofdengue virus(DENV)nucleic acids in Aedesmosquitoes and acute phase serum samples from suspected dengue fever patients using reverse transcription-polymerase chain reaction,and nucleic acid positive samples were inoculated into Vero cells for viral culture.After three consecutive blind passage,samples with cytopathic effect(CPE)were collected for be sequencingand analysisof genetic and evolutionary information.Dengue case characteristics were analyzed through descriptive epidemiological methods.Among the 109 cases of dengue fever,the ratio of males to females was 1.27∶1.The youngest patient was 1 year old,the oldest patient was 84 years old,the age group of 20～59 years accounted for 73.39%,and the major-ity of occupations were freelancer(40.37%).A total of 827 female Aedes albopictus and 312 Aedes aegypti were collected,all of which tested negative for DENV nucleic acid.109 serum samples tested positive for DENV nucleic acid,including 49 DENV-1 and 60 DENV-2.Moreover,five DENV-1 and nine DENV-2 samples were obtainedthrough third-generation blind passaging with CPE.The E gene sequences of these five DENV-1 strains were detected,all were found to belong to DENV-1 genotype I,and had same evolu-tionary branch as the 2023 Guangzhou,China(PP563911),the 2019 Myanmar(MW793710),and 2019 Attapeu,Laos(MW559046).The nucleotide and amino acid sequence similarityamong the five DENV-1 genotype was 99.4%-99.9%and 99.8%-100.0%.Compared with the aforementioned epidemic strains,their nucleotide similarities were 99.5%-100.0%,99.4%-99.6%and 99.3%-99.5%,respec-tively,and amino acid similarity was 99.8%-100.0%.Nine DENV-2 E gene sequences were of Asian genotype I and belonged to the same evolutionary branch as the 2018 Myanmar(MW788982),2019 Hangzhou(OP684212)and 2019 Ruili(OQ928150).The nucleotide and amino acid similarities of the nine samples were 99.5%-100.0%and 99.8%-100.0%,respectively.Compared with the aforementioned epidemic strains,their nucleotide similarities were 99.7%-100.0%,99.3%-99.7%and 99.3%-99.7%,respectively,and the amino acid similarity was 99.8%-100%,99.8%-100.0%and 99.4%-99.6%,respectively.Two dengue vectors,Aedes albopictus and Aedes aegypti,were present in Ruili city,and the dengue outbreak was caused primarily by DENV-1 genotype I and DENV-2 Asian genotype I in later 2023.The sources of DENV-1 were probably the same as those of DENV-1 with Guangzhou(2023),and the sources of DENV-2 were probably from Myanmar.Dengue cases were found primarilyin the 20-59 year age group and freelancers,thus suggesting that relevant local departments should strengthen surveillance of dengue imported case and vector.

Objective:To investigate the clinicopathological and genetic characteristics of monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL).Methods:The forty-two MEITL cases diagnosed in the Department of Pathology, Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China from 2016 to 2022 was retrospectively analyzed. Clinical data were collected, and follow-up was performed. Morphological characteristics were observed. Immunohistochemistry, Epstein-Barr virus (EBV) in situ hybridization, clonal rearrangement analysis of T-cell receptor (TCR) genes, and targeted next-generation sequencing (NGS) were performed.Results:Among the 42 patients (male/female ratio of 2.8∶1.0), the age range was 32-77 years with a median age of 59.5 (52.0-65.0) years. Grossly, the tumors were presented as ulcerative or exophytic lesions, with a maximum diameter of 2-18 cm. There were 34 cases with a single lesion and 8 cases with more than 1 lesion. The tumor cells in all 42 cases were relatively monotonous in histology and small or medium in size. They had round or oval nuclei, moderately pale or clear cytoplasm, evenly distributed nuclear chromatin, inconspicuous nucleoli, and frequent mitotic figures. In one of the cases, there were moderately large cells, vacuolated nuclei, and clear nucleoli. Lymphoepithelial lesions were observed in 36 (85.7%) of the 42 cases, tumor necrosis in 4 (9.5%) cases, scattered eosinophils and/or plasma cell infiltration in the background in 9 (21.4%) cases, and a "starry sky" phenomenon in 1 (2.4%) case. The tumor cells in all cases exhibited high expression of CD3, CD2, CD7, CD8, CD56, TIA1, Granzyme B, and Perforin, while some also expressed CD4 (5/41, 12.2%), CD5 (3/41, 7.3%), CD20 (4/41, 11.9%), CD79α (2/37, 5.4%), and CD30 (1/34, 2.9%). The Ki-67 proliferation index ranged from 40% to 90%. EBER in situ hybridization tests were negative in all cases. TCR gene clonal rearrangement was detected in 96.4% (27/28) of the tested cases. Targeted NGS revealed commonly mutated genes including SETD2, STAT5B, JAK3, TP53, and CREBBP. The primary treatment was chemotherapy, with 2 cases undergoing autologous hematopoietic stem cell transplantation. Follow-up information was obtained for 29 cases, with a follow-up period of 1-73 months. The mortality was 93.1% (27/29).Conclusions:MEITL is a rare and highly aggressive peripheral T-cell lymphoma. Its clinical manifestations are diverse, and diagnosis primarily relies on a comprehensive assessment of pathological morphology, immunohistochemical profiles, and EBV infection status, supplemented by genetic testing if necessary. At present, there is no effective treatment, and its overall prognosis is poor.

This article reports the first case of percutaneous closure of patent foramen ovale(PFO)using a biodegradable occluder under echocardiography guidance.The patient is a 43-year-old female diagnosed with PFO-related stroke.The procedure was successfully completed under echocardiography guidance without complications.During the 48-month follow-up period,the patient experienced no recurrent strokes,and the occluder was fully degraded.

Purpose To investigate the clinicopathological features and prognosis of adult large B-cell lymphoma with IRF4 rearrangement(LBCL-IRF4r).Methods Clinical data of 63 adult LBCL-IRF4r cases were collected.The EnVision two-step method was employed for immunohistochemical staining,and fluorescence in situ hybridization was used to detect rearrangements or deletions of the IRF4,BCL2,MYC,BCL6,and TP53 genes.The relationship be-tween clinicopathological features and prognosis was analyzed and compared with data from 132 adult non-specified dif-fuse large B-cell lymphoma(DLBCL)cases.Results Among the 63 adult LBCL-IRF4r patients,the male to female ratio was 1.1∶1,with a median age of 54.0 years(range 20-84 years),and 14 cases(22.2％)were＜40 years old,24 cases(38.1％)were between 40 and 60 years old,and 25 cases(39.7％)were＞60 years old.18 cases(28.6％)were involved in Waldeyer's ring,along with 8 cases(12.7％)in cervical lymph nodes,7 cases(11.1％)in other lymph nodes and lymphatic organs,13 cases(20.6％)in stomach,4 cases(6.4％)in intestine,and 13 cases(20.6％)in other extranodal sites.63 cases showed IRF4 rearrangements,with no BCL2 and MYC translocations(0/58),30.9％(17/55)had BCL6 translocations,and 16.3％(8/49)had TP53 deletions.59 pa-tients were followed up for a median of 28 months(range 1-65 months).48 patients(81.4％)achieved complete re-sponse,10 patients(16.9％)experienced disease progression or relapse,and 3 patients(5.1％)died.Univariate a-nalysis showed that lactate dehydrogenase level,Ann Arbor stage,international prognostic index(IPI)score,growth pattern,Hans classification,and double expression of BCL2 and C-MYC were significantly associated with progression-free survival.Age,Ann Arbor stage,and IPI score were significantly associated with overall survival.Multivariate Cox regression analysis showed that double expression of BCL2 and C-MYC was an independent prognostic factor for pro-gression-free survival.Adult LBCL-IRF4r had significantly higher complete response rate and progression-free survival than adult DLBCL.Conclusion LBCL-IRF4r occurs in adults of all age groups,commonly affecting Waldeyer's ring,cervical lymph nodes,and gastrointestinal tract,and has a favorable clinical prognosis.

Purpose To investigate the clinical,imaging,and pathological features of Kikuchi-Fujimoto disease(KFD).Methods A retrospective analysis was conducted on 123 pathologically confirmed KFD cases.Clinical and imaging data were collected,and histopathological features were evaluated using HE staining,immunohistochemistry,in situ hybridization for EBER,and molecular analyses(TCR/Ig gene rearrangements by PCR with capillary electro-phoresis).Results Among the 123 patients,the male-to-female ratio was 1∶2,with a median age of 30 years.All patients presented with lymphadenopathy.Among 30 hospitalized patients,63.3％(19/30)had fever,and 23.3％(7/30)had concurrent autoimmune diseases.Of the 12 patients who underwent PET-CT,91.7％(11/12)were sus-pected of malignancy,prompting biopsy recommendations.Among 47 consultation cases,27.7％(13/47)were ini-tially misdiagnosed as lymphoma.Histopathological examination revealed proliferative,necrotic,and xanthomatous phases,which coexisted or occurred independently.The proliferative phase was characterized by atypical lymphocytes and histiocytes,the necrotic phase by abundant eosinophilic fibrin deposits and nuclear debris,and the xanthomatous phase by clusters of foam-like histiocytes.Immunohistochemically analyses revealed that atypical lymphocytes were neg-ative for CD20,CD4,and CD56 but positive for CD3,CD8,TIA1,Granzyme B,and Perforin.Histiocytes expressed CD68,CD163,and MPO,while CD123-positive plasmacytoid dendritic cells were predominantly located around the le-sions and blood vessels.EBER was positive in individual cells in 4 cases.TCR gene rearrangement was positive in 2 cases and suspected positive in 3 cases,while Ig rearrangement was positive and suspected positive in 1 case each.Conclusion KFD exhibits clinical,imaging,and pathological features that can mimic lymphoma,highlighting the im-portance of accurate diagnosis to avoid misdiagnosis and inappropriate treatment.

Purpose To investigate the clinicopathological features and prognosis of adult large B-cell lymphoma with IRF4 rearrangement(LBCL-IRF4r).Methods Clinical data of 63 adult LBCL-IRF4r cases were collected.The EnVision two-step method was employed for immunohistochemical staining,and fluorescence in situ hybridization was used to detect rearrangements or deletions of the IRF4,BCL2,MYC,BCL6,and TP53 genes.The relationship be-tween clinicopathological features and prognosis was analyzed and compared with data from 132 adult non-specified dif-fuse large B-cell lymphoma(DLBCL)cases.Results Among the 63 adult LBCL-IRF4r patients,the male to female ratio was 1.1∶1,with a median age of 54.0 years(range 20-84 years),and 14 cases(22.2％)were＜40 years old,24 cases(38.1％)were between 40 and 60 years old,and 25 cases(39.7％)were＞60 years old.18 cases(28.6％)were involved in Waldeyer's ring,along with 8 cases(12.7％)in cervical lymph nodes,7 cases(11.1％)in other lymph nodes and lymphatic organs,13 cases(20.6％)in stomach,4 cases(6.4％)in intestine,and 13 cases(20.6％)in other extranodal sites.63 cases showed IRF4 rearrangements,with no BCL2 and MYC translocations(0/58),30.9％(17/55)had BCL6 translocations,and 16.3％(8/49)had TP53 deletions.59 pa-tients were followed up for a median of 28 months(range 1-65 months).48 patients(81.4％)achieved complete re-sponse,10 patients(16.9％)experienced disease progression or relapse,and 3 patients(5.1％)died.Univariate a-nalysis showed that lactate dehydrogenase level,Ann Arbor stage,international prognostic index(IPI)score,growth pattern,Hans classification,and double expression of BCL2 and C-MYC were significantly associated with progression-free survival.Age,Ann Arbor stage,and IPI score were significantly associated with overall survival.Multivariate Cox regression analysis showed that double expression of BCL2 and C-MYC was an independent prognostic factor for pro-gression-free survival.Adult LBCL-IRF4r had significantly higher complete response rate and progression-free survival than adult DLBCL.Conclusion LBCL-IRF4r occurs in adults of all age groups,commonly affecting Waldeyer's ring,cervical lymph nodes,and gastrointestinal tract,and has a favorable clinical prognosis.

This article reports the first case of percutaneous closure of patent foramen ovale(PFO)using a biodegradable occluder under echocardiography guidance.The patient is a 43-year-old female diagnosed with PFO-related stroke.The procedure was successfully completed under echocardiography guidance without complications.During the 48-month follow-up period,the patient experienced no recurrent strokes,and the occluder was fully degraded.

Purpose To investigate the clinical,imaging,and pathological features of Kikuchi-Fujimoto disease(KFD).Methods A retrospective analysis was conducted on 123 pathologically confirmed KFD cases.Clinical and imaging data were collected,and histopathological features were evaluated using HE staining,immunohistochemistry,in situ hybridization for EBER,and molecular analyses(TCR/Ig gene rearrangements by PCR with capillary electro-phoresis).Results Among the 123 patients,the male-to-female ratio was 1∶2,with a median age of 30 years.All patients presented with lymphadenopathy.Among 30 hospitalized patients,63.3％(19/30)had fever,and 23.3％(7/30)had concurrent autoimmune diseases.Of the 12 patients who underwent PET-CT,91.7％(11/12)were sus-pected of malignancy,prompting biopsy recommendations.Among 47 consultation cases,27.7％(13/47)were ini-tially misdiagnosed as lymphoma.Histopathological examination revealed proliferative,necrotic,and xanthomatous phases,which coexisted or occurred independently.The proliferative phase was characterized by atypical lymphocytes and histiocytes,the necrotic phase by abundant eosinophilic fibrin deposits and nuclear debris,and the xanthomatous phase by clusters of foam-like histiocytes.Immunohistochemically analyses revealed that atypical lymphocytes were neg-ative for CD20,CD4,and CD56 but positive for CD3,CD8,TIA1,Granzyme B,and Perforin.Histiocytes expressed CD68,CD163,and MPO,while CD123-positive plasmacytoid dendritic cells were predominantly located around the le-sions and blood vessels.EBER was positive in individual cells in 4 cases.TCR gene rearrangement was positive in 2 cases and suspected positive in 3 cases,while Ig rearrangement was positive and suspected positive in 1 case each.Conclusion KFD exhibits clinical,imaging,and pathological features that can mimic lymphoma,highlighting the im-portance of accurate diagnosis to avoid misdiagnosis and inappropriate treatment.

This study was aimed atanalyzing the epidemic characteristics of dengue fever in Ruili City atthe China-Myanmar bor-der in late 2023,to provide evidence for local dengue fever prevention and control measures.Adult Aedes mosquitoes were collected from Ruili City with a backpack type mosquito sucking machine in October of 2023.Serum samples frompatients with suspected den-gue were collected in acutephase,in November of 2023.Detection ofdengue virus(DENV)nucleic acids in Aedesmosquitoes and acute phase serum samples from suspected dengue fever patients using reverse transcription-polymerase chain reaction,and nucleic acid positive samples were inoculated into Vero cells for viral culture.After three consecutive blind passage,samples with cytopathic effect(CPE)were collected for be sequencingand analysisof genetic and evolutionary information.Dengue case characteristics were analyzed through descriptive epidemiological methods.Among the 109 cases of dengue fever,the ratio of males to females was 1.27∶1.The youngest patient was 1 year old,the oldest patient was 84 years old,the age group of 20～59 years accounted for 73.39%,and the major-ity of occupations were freelancer(40.37%).A total of 827 female Aedes albopictus and 312 Aedes aegypti were collected,all of which tested negative for DENV nucleic acid.109 serum samples tested positive for DENV nucleic acid,including 49 DENV-1 and 60 DENV-2.Moreover,five DENV-1 and nine DENV-2 samples were obtainedthrough third-generation blind passaging with CPE.The E gene sequences of these five DENV-1 strains were detected,all were found to belong to DENV-1 genotype I,and had same evolu-tionary branch as the 2023 Guangzhou,China(PP563911),the 2019 Myanmar(MW793710),and 2019 Attapeu,Laos(MW559046).The nucleotide and amino acid sequence similarityamong the five DENV-1 genotype was 99.4%-99.9%and 99.8%-100.0%.Compared with the aforementioned epidemic strains,their nucleotide similarities were 99.5%-100.0%,99.4%-99.6%and 99.3%-99.5%,respec-tively,and amino acid similarity was 99.8%-100.0%.Nine DENV-2 E gene sequences were of Asian genotype I and belonged to the same evolutionary branch as the 2018 Myanmar(MW788982),2019 Hangzhou(OP684212)and 2019 Ruili(OQ928150).The nucleotide and amino acid similarities of the nine samples were 99.5%-100.0%and 99.8%-100.0%,respectively.Compared with the aforementioned epidemic strains,their nucleotide similarities were 99.7%-100.0%,99.3%-99.7%and 99.3%-99.7%,respectively,and the amino acid similarity was 99.8%-100%,99.8%-100.0%and 99.4%-99.6%,respectively.Two dengue vectors,Aedes albopictus and Aedes aegypti,were present in Ruili city,and the dengue outbreak was caused primarily by DENV-1 genotype I and DENV-2 Asian genotype I in later 2023.The sources of DENV-1 were probably the same as those of DENV-1 with Guangzhou(2023),and the sources of DENV-2 were probably from Myanmar.Dengue cases were found primarilyin the 20-59 year age group and freelancers,thus suggesting that relevant local departments should strengthen surveillance of dengue imported case and vector.

Objective:To investigate the clinicopathological and genetic characteristics of monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL).Methods:The forty-two MEITL cases diagnosed in the Department of Pathology, Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China from 2016 to 2022 was retrospectively analyzed. Clinical data were collected, and follow-up was performed. Morphological characteristics were observed. Immunohistochemistry, Epstein-Barr virus (EBV) in situ hybridization, clonal rearrangement analysis of T-cell receptor (TCR) genes, and targeted next-generation sequencing (NGS) were performed.Results:Among the 42 patients (male/female ratio of 2.8∶1.0), the age range was 32-77 years with a median age of 59.5 (52.0-65.0) years. Grossly, the tumors were presented as ulcerative or exophytic lesions, with a maximum diameter of 2-18 cm. There were 34 cases with a single lesion and 8 cases with more than 1 lesion. The tumor cells in all 42 cases were relatively monotonous in histology and small or medium in size. They had round or oval nuclei, moderately pale or clear cytoplasm, evenly distributed nuclear chromatin, inconspicuous nucleoli, and frequent mitotic figures. In one of the cases, there were moderately large cells, vacuolated nuclei, and clear nucleoli. Lymphoepithelial lesions were observed in 36 (85.7%) of the 42 cases, tumor necrosis in 4 (9.5%) cases, scattered eosinophils and/or plasma cell infiltration in the background in 9 (21.4%) cases, and a "starry sky" phenomenon in 1 (2.4%) case. The tumor cells in all cases exhibited high expression of CD3, CD2, CD7, CD8, CD56, TIA1, Granzyme B, and Perforin, while some also expressed CD4 (5/41, 12.2%), CD5 (3/41, 7.3%), CD20 (4/41, 11.9%), CD79α (2/37, 5.4%), and CD30 (1/34, 2.9%). The Ki-67 proliferation index ranged from 40% to 90%. EBER in situ hybridization tests were negative in all cases. TCR gene clonal rearrangement was detected in 96.4% (27/28) of the tested cases. Targeted NGS revealed commonly mutated genes including SETD2, STAT5B, JAK3, TP53, and CREBBP. The primary treatment was chemotherapy, with 2 cases undergoing autologous hematopoietic stem cell transplantation. Follow-up information was obtained for 29 cases, with a follow-up period of 1-73 months. The mortality was 93.1% (27/29).Conclusions:MEITL is a rare and highly aggressive peripheral T-cell lymphoma. Its clinical manifestations are diverse, and diagnosis primarily relies on a comprehensive assessment of pathological morphology, immunohistochemical profiles, and EBV infection status, supplemented by genetic testing if necessary. At present, there is no effective treatment, and its overall prognosis is poor.