Coronavirus disease 2019 (COVID-19) is a multi-system disease that can lead to various severe complications. Acute limb ischemia (ALI) has been increasingly recognized as a COVID-19-associated complication that often predicts a poor prognosis. However, the pathophysiology and molecular mechanisms underlying COVID-19-associated ALI remain poorly understood. Hypercoagulability and thrombosis are considered important mechanisms, but we also emphasize the roles of vasospasm, hypoxia, and acidosis in the pathogenesis of the disease. The angiotensin-converting enzyme 2 (ACE2) pathway, inflammation, and platelet activation may be important molecular mechanisms underlying these pathological changes induced by COVID-19. Furthermore, we discuss the hypotheses of risk factors for COVID-19-associated ALI from genetic, age, and gender perspectives based on our analysis of molecular mechanisms. Additionally, we summarize therapeutic approaches such as use of the interleukin-6 (IL-6) blocker tocilizumab, calcium channel blockers, and angiotensin-converting enzyme inhibitors, providing insights for the future treatment of coronavirus-associated limb ischemic diseases.
Humans ; COVID-19/physiopathology* ; Ischemia/etiology* ; SARS-CoV-2 ; Extremities/blood supply* ; Risk Factors ; Interleukin-6/antagonists & inhibitors* ; Acute Disease ; Angiotensin-Converting Enzyme 2

Objective:To explore the genetic basis for a child with developmental delay and intellectual deficit (DD/ID).Methods:A child who was admitted to the Maternal and Child Health Care Hospital of Longhua District of Shenzhen City on June 3, 2023 due to DD/ID, craniofacial malformations, and recurrent infections of upper respiratory tract was selected as the study subject. G-banded chromosomal karyotyping was carried out for the child and her parents. Low-depth genome-wide copy number variation sequencing (CNV-seq) and chromosomal microarray analysis (CMA) were used to screen for genome-wide copy number variation (CNV), and fluorescence in situ hybridization (FISH) was used to verify the origin of candidate CNV. This study was approved by the Maternal and Child Health Care Hospital of Longhua District of Shenzhen City(Ethics No. 2023052504). Results:The child, an 8-year-old girl, had featured unexplained growth and intellectual development delay, multiple craniofacial malformations, and recurrent infections of the upper respiratory tract. She was found to have a karyotype of 46, XX, der(6)add(6)(q23), while both of her parents were normal. Both CNV-seq and CMA showed that the child has harbored a 21.38 Mb interstitial duplication at 6p25.3p22.3 and a 0.78 Mb terminal deletion at 6p25. FISH verified that both the duplication and deletion had occurred de novo. Conclusion:The abnormal phenotype of the child may be attributed to the 6p duplication and terminal deletion.

Acral melanoma(AM)is the most common histologic subtype of melanoma in dark-skinned patients and is associated with a worse prognosis and a high mortality rate,largely due to the inconspicuous nature of early-stage lesions,which can lead to late diagnosis.Because of the overlapping clinical and histopathological features of AM with other forms of cutaneous melanomas,early detection of AM requires a multidisciplinary approach that integrates various diagnostic modalities,including clinical examination,dermoscopy,histopathology,molecular testing,radiological imaging,and blood tests.While surgery is the preferred method of treatment for AM,other therapeutic options may be employed based on the stage and underlying etiology of the disease.Immune checkpoint inhibitors,molecular targeted therapy,radiotherapy,chemotherapy,and oncolytic virotherapy represent promising advanced treatment options for AM.In this review,we provide an overview of the latest advancements in diagnostic and therapeutic methods for AM,highlighting the importance of early detection and the prompt,individualized management of this challenging disease.

Objective To assess the application value of sequential non-invasive prenatal testing(NIPT)for pregnant women with abnormal single values of early Down's screening.Methods A total of 1 631 pregnant women with abnormal single values of traditional early Down's screening were selected from Shenzhen Long-hua Maternal and Child Health Hospital from January to October in 2022,and all of them voluntarily under-went NIPT with signed informed consent.The high-risk samples screned by NIPT wre conducted invasive prenatal diagnosis and tracked pregnancy outcomes,and yet low-risk pregnant women was followed up after the due date.Results Among all the pregnant women,a total of 10 high-risk samples of fetal chromosomal aneuploidy were detected by sequential NIPT,including 1 case of trisomy 21,1 case of trisomy 18,7 cases of sex chromosome abnormalities,and 1 case of other autosomal abnormalities.9 cases of high-risk pregnant women received invasive prenatal diagnosis,and 5 cases were consistent with NIPT results,which had yielded a positive predictive value of 55.56％.Among them,the positive predictive values of trisomy 21,trisomy 18,sex chromosome abnormalities and other autosomal abnormalities were 100.00％,100.00％,50.00％,0.00％,resepectively.Conclusion Sequential NIPT could improve the detection of defective children in pregnant women with abnormal single values of early Down's screening,which has certain guiding value for expanding screening to reduce the birth of defective children.In view of its low positive predictive value,pregnant women with abnormal single value of Down's screening should be paid more attention,and further prenatal diagnosis may be necessary to reduce the birth rate of defective children.