Novel nonsense and frameshift NTRK1 gene mutations in Chinese patients with congenital insensitivity to pain with anhidrosis.

Congenital insensitivity to pain with anhidrosis (CIPA; MIM 256800) is a rare autosomal recessive disorder characterized by absence of reaction to noxious stimuli, recurrent episodes of fever, anhidrosis, and mental retardation. It is caused by mutations in the gene coding for neurotrophic tyrosine kinase receptor type 1 (NTRK1; MIM# 191315). We screened two Chinese CIPA cases for mutations in the NTRK1 gene and examined their phenotype. Two novel mutations of the NTRK1 gene and two known mutations were identified. Including our two novel mutations, there are now 62 different NTRK1 gene mutations reported in patients with CIPA. We find that a combination of two null alleles usually leads to the severe phenotype, while the mild form of the CIPA disease is associated with at least one mild allele. Thirty-four among the 62 mutations (55%) are located within the tyrosine kinase domain of the NTRK1 protein. We concluded that the tyrosine kinase domain is a hot spot for mutations.

[Establishment of an auxiliary diagnosis system of newborn screening for inherited metabolic diseases based on artificial intelligence technology and a clinical trial].

Objective: To establish a disease risk prediction model for the newborn screening system of inherited metabolic diseases by artificial intelligence technology. Methods: This was a retrospectively study. Newborn screening data (n=5 907 547) from February 2010 to May 2019 from 31 hospitals in China and verified data (n=3 028) from 34 hospitals of the same period were collected to establish the artificial intelligence model for the prediction of inherited metabolic diseases in neonates. The validity of the artificial intelligence disease risk prediction model was verified by 360 814 newborns' screening data from January 2018 to September 2018 through a single-blind experiment. The effectiveness of the artificial intelligence disease risk prediction model was verified by comparing the detection rate of clinically confirmed cases, the positive rate of initial screening and the positive predictive value between the clinicians and the artificial intelligence prediction model of inherited metabolic diseases. Results: A total of 3 665 697 newborns' screening data were collected including 3 019 cases' positive data to establish the 16 artificial intelligence models for 32 inherited metabolic diseases. The single-blind experiment (n=360 814) showed that 45 clinically diagnosed infants were detected by both artificial intelligence model and clinicians. A total of 2 684 cases were positive in tandem mass spectrometry screening and 1 694 cases were with high risk in artificial intelligence prediction model of inherited metabolic diseases, with the positive rates of tandem 0.74% (2 684/360 814)and 0.46% (1 694/360 814), respectively. Compared to clinicians, the positive rate of newborns was reduced by 36.89% (990/2 684) after the application of the artificial intelligence model, and the positive predictive values of clinicians and artificial intelligence prediction model of inherited metabolic diseases were 1.68% (45/2 684) and 2.66% (45/1 694) respectively. Conclusion: An accurate, fast, and the lower false positive rate auxiliary diagnosis system for neonatal inherited metabolic diseases by artificial intelligence technology has been established, which may have an important clinical value.

Homocysteine induced oxidative stress in human umbilical vein endothelial cells via regulating methylation of SORBS1.

OBJECTIVE: The aim of the present study was to investigate the mechanism of homocysteine (Hcy) induced oxidative stress in the human umbilical vein endothelial cells (HUVECs). PATIENTS AND METHODS: The HUVECs were isolated from umbilical vein vascular wall of 12 patients and treated with Hcy. The malondialdehyde (MDA) level was measured using the thiobarbituric acid (TBA) method. The expressions of superoxide dismutase 2 (SOD2), endothelial nitric oxide synthase (eNOS), and intercellular adhesion molecule 1 (ICAM-1) were detected by Western blot and RT-PCR. The genome-wide DNA methylation assay was performed using the Infinium Human Methylation 450 BeadChip. The specific DNA methylation was determined using bisulfite sequencing analysis. To evaluate the role of sorbin and SH3 domain-containing protein 1 (SORBS1), the HUVECs were transfected with small interfere RNA (siRNA) targeting SORBS1 (SORBS1-siRNA). RESULTS: Hcy induced MDA level in HUVECs, and increased ICAM-1 expression both in protein and mRNA levels. The protein and mRNA levels of SOD2 and eNOS were inhibited by Hcy induction. However, the effects of Hcy on MDA level and expressions of SOD2, eNOS, and ICAM-1 were attenuated by folic acid (Fc) and vitamin B12 (B12) treatment. DNA total methylation level in Hcy treated cells was significantly decreased compared to the control group, while the DNA total methylation levels were increased after treatment with Fc and B12. The methylation level of SORBS1 in Hcy treatment group was higher than that of control group. And the methylation level of SORBS1 induced by Hcy was attenuated by Fc and B12 treatment. SORBS1-siRNA transfection induced the MDA levels and reduced the expressions of SOD2 in HUVECs. CONCLUSIONS: We indicated that Hcy induced oxidative stress in HUVECs via regulating methylation of SORBS1. We also found that Fc and B12 treatment attenuated the oxidative stress and inflammation induced by Hcy in HUVECs. The findings indicated that Fc and B12 might be effective agents for the treatment of Hcy induced AS.

[Preliminary analysis of 18 cases of malignant lymphoma by immunohistological method with various monoclonal and polyclonal antibodies].

Eighteen cases of malignant lymphoma were labelled by ABC immunohistologic method with various monoclonal and polyclonal antibodies. It was found that all were OKT9 antiserum positive and cytokeratin negative. In B cell lymphomas, 9/18 cases were positive for B1; 7 positive for each of I2+ and Leu 10+; 6 for J5+, and 5 for B2+. In 6 cases of T cell lymphoma, 5 cases were positive for T3+ and Tac+ each; 4 for T11+ and 2 for T6+ while all were positive for T4 and negative or weakly positive for T8A. There was 1 case of histiocytic lymphoma and 2 of Hodgkin's lymphoma showing positive reaction to MO1, 2H9 and lysozyme antibody in their tumor cells and R-S cells.

Pyoderma gangraenosum caused by Rhizopus arrhizus.

A rare case of pyoderma gangraenosum caused by Rhizopus arrhizus is reported. The patient, a 50-year-old male farmer, was admitted to hospital complaining of gangrening and festering of the right upper arm with severe pain for nearly 2 months. A lesion was found on the inside of right upper arm. The central skin part of the lesion became black dry gangrenous, the periphery was deeply ulcerated with yellow-green pus. The necrotic crust, biceps, triceps and vessels inherited a histopathologically proven fungal infection. The fungus isolated was identified as Rhizopus arrhizus. The infection was successfully treated with itraconazole.