Distinct tomato yellow leaf curl Chuxiong virus isolated from whiteflies and plants in China and its symptom determinant and suppressor of post-transcriptional gene silencing.

A begomovirus isolated from whiteflies (Bemisia tabaci) and tomato, sweet potato in China was found to be representative of a distinct begomovirus species, for which the name tomato yellow leaf curl Chuxiong virus (TYLCCxV) is proposed. The results of genomic identification and sequence comparison showed that TYLCCxV shares the highest complete nucleotide sequence identity (88.3%) with croton yellow vein mosaic virus (CroYVMV), and may have originated from the recombination between synedrella leaf curl virus (SyLCV) and squash leaf curl Yunnan virus (SLCuYV). Agrobacterium-mediated inoculation showed that TYLCCxV is highly infectious for a range of plant species, producing upward leaf curling, leaf crumpling, chlorosis, distortion, and stunt symptoms in Solanum lycopersicum plants. The results of Southern blot indicated that TYLCCxV is capable of efficiently replicating two heterologous betasatellites. The inoculation of PVX::C4 on Nicotiana benthamiana induced upward leaf curling and stem elongation symptoms, suggesting that TYLCCxV C4 functions as a symptom determinant. TYLCCxV V2 is an important virulence factor that induces downward leaf curling symptoms, elicits systemic necrosis, and suppresses local and systemic GFP silencing in co-agroinfiltrated N. benthamiana and transgenic 16c plants. Considering the multifunctional virulence proteins V2 and C4, the possibility of TYLCCxV causing devastating epidemics on tomato in China is discussed.

Serum levels of CXCL5 are decreased and correlate with circulating platelet counts in systemic lupus erythematosus.

OBJECTIVE: To identify disease-specific serum chemokine profiles and potential anti-inflammatory chemokines in three rheumatic diseases. METHODS: The discovery cohort included 18 patients with rheumatoid arthritis (RA), 20 patients with primary Sjögren's syndrome (pSS), 24 patients with systemic lupus erythematosus (SLE) and 28 healthy subjects. Findings from the discovery cohort were validated in two replication cohorts, consisting of 23 patients with SLE matched with 23 healthy subjects and 62 patients with SLE, 16 patients with ANCA-associated vasculitis (AAV), and 32 healthy controls, respectively. Serum levels of chemokines were determined using multiplex assay or ELISA. RESULTS: In the discovery cohort, serum levels of multiple chemokines were increased in one or more diseases in comparison to healthy subjects, including CCL2, CCL20, CXCL9, CXCL10, and CXCL11 in SLE, CCL2, CCL4, and CXCL11 in pSS, and CCL2, CCL4, and CXCL9 in RA. Notably, serum levels of CCL3 (p = .0003) and CXCL5 (p = .0003) were decreased in SLE. The SLE-specific decrease in CXCL5 serum levels was confirmed in the two replication cohorts, with p = .0034 and p = .0006, respectively. Moreover, a positive correlation between serum levels of CXCL5 and circulating platelet counts (R = .71, p = .00018) in SLE observed in the discovery cohort was confirmed in both replication cohorts (R = .52, p = .011 and R = .49, p = .00005, respectively). CONCLUSION: In the present study, we demonstrate that serum levels of CXCL5 are decreased in patients with SLE and positively correlated with circulating platelet count. These findings suggest that platelet-associated CXCL5 is presumably involved in the development of SLE.

Case report: Treatment of Wilson's disease by human amniotic fluid administration.

Background: Wilson's disease (WD) is not an uncommon genetic disease in clinical practice. However, the current WD therapies have limitations. The effectiveness of stem cell therapy in treating WD has yet to be verified, although a few animal studies have shown that stem cell transplantation could partially correct the abnormal metabolic phenotype of WD. In this case report, we present the therapeutic effect of human amniotic fluid containing stem cells in one WD patient. Case presentation: A 22-year-old Chinese woman was diagnosed with WD 1 year ago in 2019. The available drugs were not effective in managing the progressive neuropsychiatric symptoms. We treated the patient with pre-cultured human amniotic fluid containing stem cells. Amniotic fluid was collected from pregnant women who underwent induced labor at a gestational age of 19-26 weeks, and then, the fluid was cultured for 2 h to allow stem cell expansion. Cultured amniotic fluid that contained amniotic fluid derived stem cells (AFSC) in the range of approximately 2.8-5.5 × 104/ml was administrated by IV infusion at a rate of 50-70 drops per minute after filtration with a 300-mu nylon mesh. Before the infusion of amniotic fluid, low-molecular-weight heparin and dexamethasone were successively administrated. The patient received a total of 12 applications of amniotic fluid from different pregnant women, and the treatment interval depended on the availability of amniotic fluid. The neuropsychiatric symptoms gradually improved after the stem cell treatment. Dystonia, which included tremor, chorea, dysphagia, dysarthria, and drooling, almost disappeared after 1.5 years of follow-up. The Unified Wilson's Disease Rating Scale score of the patient decreased from 72 to 10. Brain magnetic resonance imaging (MRI) showed a reduction in the lesion area and alleviation of damage in the central nervous system, along with a partial recovery of the lesion to the normal condition. The serum ceruloplasmin level was elevated from undetectable to 30.8 mg/L, and the 24-h urinary copper excretion decreased from 171 to 37 µg. In addition, amniotic fluid transplantation also alleviates hematopoietic disorders. There were no adverse reactions during or after amniotic fluid administration. Conclusion: Amniotic fluid administration, through which stem cells were infused, significantly improves the clinical outcomes in the WD patient, and the finding may provide a novel approach for managing WD effectively.

Molecular mechanism of calcitriol enhances membrane water permeability.

Helicobacter pylori (H. pylori) exhibits a unique membrane lipid composition, including dimyristoyl phosphatidylethanolamine (DMPE) and cholesterol, unlike other Gram-negative bacteria. Calcitriol has antimicrobial activity against H. pylori, but cholesterol enhances antibiotics resistance in H. pylori. This study explored the changes in membrane structure and the molecular mechanisms of cholesterol/calcitriol translocation using well-tempered metadynamics (WT-MetaD) simulations and microsecond conventional molecular dynamics (CMD) simulations. Calcitriol facilitated water transport across the membrane, while cholesterol had the opposite effect. The differing effects might result from the tail 25-hydroxyl group and a wider range of orientations of calcitriol in the DMPE/dimyristoyl phosphatidylglycerol (DMPG) (3:1) membrane. Calcitriol moves across the bilayer center without changing its orientation along the membrane Z-axis, becomes parallel to the membrane surface at the membrane-water interface, and then rotates approximately 90° in this interface. The translocation mechanism of calcitriol is quite different from the flip-flop of cholesterol. Moreover, calcitriol crossed from one layer to another more easily than cholesterol, causing successive perturbations to the hydrophobic core and increasing water permeation. These results improve our understanding of the relationship between cholesterol/calcitriol concentrations and the lipid bilayer structure and the role of lipid composition in water permeation.

Effects of C-Terminal Lys-Arg Residue of AapA1 Protein on Toxicity and Structural Mechanism.

Previous experimental investigations have established the indispensability of the C-terminal Lys-Arg residues in the toxic activity of the AapA1 toxin protein. AapA1 is classified as a type I toxin-antitoxin (TA) bacterial toxin, and the precise impact of the C-terminal Lys-Arg residues on its structure and mechanism of action remains elusive. To address this knowledge gap, the present study employed molecular dynamics (MD) and enhanced sampling Well-tempered Two-dimensional Metadynamics (2D-MetaD) simulations to examine the behavior of the C-terminal Lys-Arg residues of truncated AapA1 toxin (AapA1-28) within the inner membrane of Escherichia coli. Specifically, the study focused on the elucidation of possible conformation states of AapA1-28 protein in POPE/POPG (3:1) bilayers and their interactions between the protein and POPE/POPG (3:1) bilayers. The findings of our investigation indicate that the AapA1-28 protein does not adopt a vertical orientation upon membrane insertion; rather, it assumes an angled conformation, with the side chain of Lys-23 directed toward the upper layer of the membrane. This non-transmembrane conformation of AapA1-28 protein impedes its ability to form pores within the membrane, resulting in reduced toxicity towards Escherichia coli. These results suggest that C-Terminal positively charged residues are essential for electrostatic binding to the negatively charged head group of bottom bilayer membrane, which stabilize the transmembrane conformation. These outcomes contribute to our comprehension of the impact of C-terminal charged residues on the structure and functionality of membrane-associated proteins, and provide an improved understanding of how protein sequence influences the antimicrobial effect.

A case of early onset diabetes with myotonic dystrophy type 1. / ä»¥æ—©å‘ç³–å°¿ç— é¦–è¯Šçš„å¼ºç›´æ€§è‚Œè¥å »ä¸è‰¯1型1例.

Myotonic dystrophy type 1 (DM1, OMIM 160900) is a rare autosomal dominant hereditary disease. A case of DM1 patient with early onset diabetes and decreased muscle strength was treated in the Department of Endocrinology, Third Xiangya Hospital, Central South University. The peripheral blood of the patient was collected to extract DNA for gene detection. It was found that the triple nucleotide CTG repeat in the 3'-untranslated region (3'-UTR) of the dystrophia myotonica protein kinase (DMPK) gene was more than 100 times, and the diagnosis of DM1 was clear. For diabetes patients with multiple system abnormalities such as muscle symptoms, attention should be paid to the screening of DM1, a rare disease.

AGO2a but not AGO2b mediates antiviral defense against infection of wild-type cucumber mosaic virus in tomato.

Evolutionarily conserved antiviral RNA interference (RNAi) mediates a primary antiviral innate immunity preventing infection of broad-spectrum viruses in plants. However, the detailed mechanism in plants is still largely unknown, especially in important agricultural crops, including tomato. Varieties of pathogenic viruses evolve to possess viral suppressors of RNA silencing (VSRs) to suppress antiviral RNAi in the host. Due to the prevalence of VSRs, it is still unknown whether antiviral RNAi truly functions to prevent invasion by natural wild-type viruses in plants and animals. In this research, for the first time we applied CRISPR-Cas9 to generate ago2a, ago2b, or ago2ab mutants for two differentiated Solanum lycopersicum AGO2s, key effectors in antiviral RNAi. We found that AGO2a but not AGO2b was significantly induced to inhibit the propagation of not only VSR-deficient Cucumber mosaic virus (CMV) but also wild-type CMV-Fny in tomato; however, neither AGO2a nor AGO2b regulated disease induction after infection with either virus. Our findings firstly reveal a prominent role of AGO2a in antiviral RNAi innate immunity in tomato and demonstrate that antiviral RNAi evolves to defend against infection of natural wild-type CMV-Fny in tomato. However, AGO2a-mediated antiviral RNAi does not play major roles in promoting tolerance of tomato plants to CMV infection for maintaining health.

Different cell compositions and a novel somatic KCNJ5 variant found in a patient with bilateral adrenocortical adenomas secreting aldosterone and cortisol.

Introduction: This study aimed to explore the possible pathogenesis of a rare case of co-existing Cushing's syndrome (CS) and primary aldosteronism (PA) caused by bilateral adrenocortical adenomas secreting aldosterone and cortisol, respectively. Methods: A 41-year-old Chinese woman with severe hypertension and hypokalemia for 5 and 2 years, respectively, was referred to our hospital. She had a Cushingoid appearance. Preoperative endocrinological examinations revealed autonomous cortisol and aldosterone secretion. Computed tomography revealed bilateral adrenal adenomas. Subsequently, adrenal vein sampling and sequential left and right partial adrenalectomy indicated the presence of a left aldosterone-producing tumor and a right cortisol-producing tumor. Pathological examination included immunohistochemical analysis of the resected specimens. Secretions of aldosterone and cortisol were observed both in vivo and in vitro. Further, whole-exome sequencing was performed for DNA that was extracted from peripheral blood leukocytes and bilateral adrenal adenomas in order to determine whether the patient had relevant variants associated with PA and CS. Results: Immunohistochemical staining revealed that the left adenoma primarily comprised clear cells expressing CYP11B2, whereas the right adenoma comprised both eosinophilic compact and clear cells expressing CYP11B1. The mRNA levels of steroidogenic enzymes (including CYP11B1 and CYP17A1) were high in the right adenoma, whereas CYP11B2 was highly expressed in the left adenoma. A novel somatic heterozygous missense variant-KCNJ5 c.503T > G (p.L168R)-was detected in the left adrenal adenoma, but no other causative variants associated with PA and CS were detected in the peripheral blood or right adrenocortical adenoma. In the primary cell culture of the resected hyperplastic adrenal adenomas, verapamil and nifedipine, which are two calcium channel blockers, markedly inhibited the secretion of both aldosterone and cortisol. Conclusion: We present an extremely rare case of bilateral adrenocortical adenomas with distinct secretion of aldosterone and cortisol. The heterogeneity of the tumor cell compositions of aldosterone- and cortisol-producing adenoma (A/CPA) and somatic mutation of KCNJ5 may have led to different hormone secretions in the bilateral adrenal adenomas.

[Analysis of a child with Marfan syndrome due to a novel variant of FBN1 gene].

OBJECTIVE: To carry out genetic testing for a child with Marfan syndrome (MFS) and explore its genotype-phenotype correlation. METHODS: Peripheral blood samples of the child and his parents were collected for the extraction of genomic DNA and subjected to whole exome sequencing (WES). Candidate variants were verified by Sanger sequencing. Functional impact of the variant was predicted by using bioinformatic software. RESULTS: The child, a 13-year-old male, has featured Marfanoid habitus, with arm span exceeding his height, tapering fingers and toes, pectus excavatum and scoliosis, but absence of typical cardiovascular system diseases such as aortic dilation, thoracic-abdominal aortic aneurysm, mitral valve prolapse, and lens dislocation. The child has harbored a novel splice site variant c.7383_7413del (p. N2461Kfs*211) of the FBN1 gene, which was not found in his parents and younger brother. The variant was unreported previously. CONCLUSION: The novel variant of p. N2461Kfs*211 of the FBN1 gene probably underlay the MFS in this child. Above finding has enriched the genotypic and phenotypic spectrum of MFS.

Genetic and Functional Analyses of the Novel KLF11 Pro193Thr Variant in a Three-Generation Family with MODY7.

KLF11 regulates insulin gene expression through binding to the insulin promoter and has been reported as a causative gene for maturity-onset diabetes of the young 7 (MODY7). Here, we report a novel KLF11 variant associated with a three-generation family with early childhood-onset diabetes and explore its clinical and functional characteristics. The three-generational pedigree contains five patients affected by diabetes. The pathogenic variant identified by whole-exome sequencing was further confirmed by Sanger sequencing and pedigree verification. Luciferase reporter assays and glucose-stimulated insulin secretion were used to examine whether the KLF11 variant binds to the insulin promoter and regulate insulin secretion in vitro. The proband, his son, and his uncle exhibited hyperglycemia at ages 32, 13 and 71 years, respectively. All three patients showed characteristics of metabolic syndrome (obesity, dyslipidemia, and diabetes), but the insulin secretion of islet ß-cells was impaired. A novel heterozygous missense variant, c.577 C>A (p.Pro193Thr) of the KLF11 gene was detected in all three patients. This variant co-segregates with the diabetes phenotype, consistent with an autosomal dominant disorder. The identified KLF11 p.Pro193Thr variant drastically decreased the transcriptional activity of KLF11, as demonstrated by luciferase reporter assay. Functional analyses revealed that the KLF11 Pro193Thr variant inhibited glucose-stimulated insulin secretion. We identified a novel KLF11 Pro193Thr variant in a three generation family with MODY7. These findings shed light on the molecular mechanisms underlying the pathogenesis of MODY7 and expand the genotype and clinical spectrum of MODY7.

Two clusters of systemic lupus erythematosus patients with muscle involvement in a Chinese cohort.

OBJECTIVES: This study aimed to depict the clinical features, including myositis specific or associated antibody (MSA/MAA) profile of systemic lupus erythematosus (SLE) patients with muscle involvement in a Chinese cohort. METHODS: We retrospectively studied a cohort of 1696 SLE inpatients and screened for concurrent myositis features from January 2013 to June 2021. Propensity score matching was applied to enroll controls without myositis features from our cohort. Demographic, clinical and laboratory variables were collected. MSA/MAA panels containing 16 autoantibodies (TIF1-γ, MDA5, NXP2, Mi-2α/ß, SAE1, Jo-1, PL-7, PL-12, EJ, OJ, SRP, HMGCR, cN-1A, PM-Scl75/100, Ku and Ro52) were tested by line-blotting assay. Binary logistic regression and K-means clustering were applied. RESULTS: Forty-one of 1696 (2.42%) SLE patients in our SLE inpatient cohort showed features of myositis. Binary logistic regression revealed that new-onset SLE (odds ratio [OR] = 4.77, 95% CI = 1.10-20.57), interstitial lung disease (ILD) (OR = 10.07, 95% CI = 1.65-61.51), positive anti-U1RNP antibody (OR = 4.38, 95% CI = 1.08-17.75), and Raynaud's phenomenon (OR = 7.94, 95% CI = 1.41-44.69) were associated with muscle involvement. Except for anti-Ro52 (50%), anti-Ku antibody (38.2%) was the next frequently detected MSA/MAA in the panel, followed by anti-NXP2 antibody (11.8%). It was noteworthy that multiple MSA/MAAs (≥2, excluding anti-Ro52) coexisted in 9 patients. Patients with myositis features were clustered into 2 subgroups. Cluster 1 was characterized by anti-Ku or anti-Ro52 with high SLE Disease Activity Index, whereas cluster 2 presented with anti-U1RNP, Raynaud's phenomenon and pulmonary arterial hypertension resembling mixed connective tissue disease. CONCLUSION: In our Chinese SLE inpatient cohort, muscle involvement was infrequent. Nevertheless, distinct features in these SLE patients deserve further study.

Muscle injuries and recovery training in college sprinters / Lesões musculares e treinamento de recuperação em velocistas universitários / Lesiones musculares y entrenamiento de recuperación en velocistas universitarios

ABSTRACT Introduction The sprint is extremely explosive, and inadequate training methods can cause irreversible muscle damage. Objective Explore the types of sports injuries, the main sites, the main factors affecting the results of physical training, and the main factors affecting recovery from muscle injuries in college and university sprinters, and propose preventive measures. Methods Taking 174 college sprinters as the research object, we analyzed the conditions related to muscle injury and physical training of sprinters, using field investigation, questionnaire survey, and mathematical statistics. The types of sports injuries, the main sites, the main factors affecting the results of physical training, and the main factors affecting college sprinters' recovery from muscle injury were investigated. Results Among the 174 athletes surveyed, 47.7% had sports injuries of different degrees, and 52.3% had no sports injuries. Different physical training methods, training time, training levels, and slack fatigue training can affect physical training results. Conclusion College sprinters should improve their safety awareness, give importance to preparatory activities and flexibility exercises, optimize strength training programs, and use physical and exercise therapy to promote recovery from muscle injuries. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução O velocismo é um esporte extremamente explosivo, e métodos de treinamento inadequados podem causar danos musculares irreversíveis. Objetivo Explorar os tipos de lesões esportivas, os principais locais, os principais fatores que afetam os resultados do treinamento físico e os principais fatores que afetam a recuperação das lesões musculares dos velocistas em faculdades e universidades, propondo medidas preventivas. Métodos Tomando 174 velocistas universitários como objeto de pesquisa, analisou-se as condições relacionadas à lesão muscular e ao treinamento físico dos velocistas, utilizando investigação de campo, levantamento de questionários e estatísticas matemáticas. Pesquisou-se os tipos de lesão esportiva, os principais locais, os principais fatores que afetam os resultados do treinamento físico e os principais fatores que afetam a recuperação da lesão muscular dos velocistas universitários. Resultados Entre os 174 atletas pesquisados, 47,7% apresentaram lesões esportivas de diferentes graus, e 52,3% não tiveram lesões esportivas. Diferentes métodos de treinamento físico, tempo de treinamento, níveis de treinamento e treinamento negligente de fadiga podem afetar os resultados do treinamento físico. Conclusão Os velocistas universitários devem melhorar sua consciência de segurança, dar importância às atividades preparatórias e aos exercícios de flexibilização, otimizar o programa de treinamento de força, usar a fisioterapia e a terapia de exercícios para promover a recuperação de lesões musculares. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción El sprint es un deporte extremadamente explosivo, y métodos de entrenamiento inadecuados pueden causar daños musculares irreversibles. Objetivo Explorar los tipos de lesiones deportivas, las principales localizaciones, los principales factores que afectan a los resultados del entrenamiento físico y los principales factores que afectan a la recuperación de las lesiones musculares en velocistas colegiales y universitarios, proponiendo medidas preventivas. Métodos Tomando como objeto de investigación 174 velocistas universitarios, se analizaron las condiciones relacionadas con las lesiones musculares y el entrenamiento físico de los velocistas mediante investigación de campo, encuesta por cuestionario y estadística matemática. Se investigaron los tipos de lesiones deportivas, las principales localizaciones, los principales factores que afectan a los resultados del entrenamiento físico y los principales factores que afectan a la recuperación de las lesiones musculares de los velocistas universitarios. Resultados De los 174 deportistas encuestados, el 47,7% tenía lesiones deportivas de distinto grado y el 52,3% no tenía lesiones deportivas. Los diferentes métodos de entrenamiento físico, el tiempo de entrenamiento, los niveles de entrenamiento y el entrenamiento descuidado por fatiga pueden afectar a los resultados del entrenamiento físico. Conclusión Los velocistas universitarios deben mejorar su conciencia de seguridad, dar importancia a las actividades preparatorias y a los ejercicios de flexibilidad, optimizar el programa de entrenamiento de fuerza, utilizar la fisioterapia y la terapia de ejercicio para promover la recuperación de las lesiones musculares. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Clinical and genetic characteristics for 4 patients with Type Ib pseudohypoparathyroidism. / 4例Ibåž‹å‡æ€§ç”²çŠ¶æ—è ºåŠŸèƒ½å‡é€€ç—‡çš„ä¸´åºŠå’Œé—ä¼ å­¦ç‰¹å¾.

Pseudohypoparayhyroidism (PHP) is a rare autosomal dominant or recessive genetic disorder characterized by low calcium, high phosphorus, and target organ resistance to parathyroid. The clinical characteristics and genetic features in 4 patients with Type Ib PHP in the Third Xiangya Hospital, Central South University, have been reviewed. All 4 patients had low calcium, high phosphorus, and parathyroid resistance. Among them, 2 patients had slightly elevated thyroid stimulating hormone and mild features of Albright's hereditary osteodystrophy, and one patient had hypokalemia. No guanine nucleotide-binding protein alpha-stimulating activity polypeptide 1 (GNAS) and gene variant associated with hypokalemia were identified using the whole exome sequencing. The results of the methylation-specific multiple ligation-dependent probe amplification showed that there were abnormal methylation of the upstream differentially methylated regions of GNAS in the 4 patients. There were phenotype overlap among the various subtypes of PHP. Detection of GNAS gene methylation in patients with clinical suspicion of Type Ib PHP is helpful for the diagnosis and treatment of PHP.

Major infections in newly diagnosed systemic lupus erythematosus: an inception cohort study.

OBJECTIVE: To evaluate the risk of major infections and the relationship between major infections and mortality in patients with newly diagnosed SLE. METHODS: A newly diagnosed (<3 months) hospitalised Systemic Lupus Inception Cohort (hSLIC) in our centre during 1 January 2013 and 1 November 2020 was established. All patients were followed up for at least 1 year or until death. Patient baseline characteristics were collected. Major infection events were recorded during follow-up, which were defined as microbiological/clinical-based diagnosis treated with intravenous antimicrobials. The cohort was further divided into a training set and a testing set. Independent predictors of major infections were identified using multivariable logistic regression analysis. Kaplan-Meier survival analyses were conducted. RESULTS: Among the 494 patients enrolled in the hSLIC cohort, there were 69 documented episodes of major infections during the first year of follow-up in 67 (14%) patients. The major infection events predominantly occurred within the first 4 months since enrolment (94%, 65/69) and were associated with all-cause mortality. After adjustments for glucocorticoid and immunosuppressant exposure, a prediction model based on SLE Disease Activity Index >10, peripheral lymphocyte count <0.8×109/L and serum creatinine >104 µmol/L was established to identify patients at low risk (3%-5%) or high risk (37%-39%) of major infections within the first 4 months. CONCLUSIONS: Newly onset active SLE is susceptible to major infections, which is probably due to underlying profound immune disturbance. Identifying high-risk patients using an appropriate prediction tool might lead to better tailored management and better outcome.

Molecular dynamics simulations to study the role of biphenylalanine in promoting the antibacterial activity of ultrashort peptides.

The hydrophobic amino acid biphenylalanine (B) plays a key role in the antibacterial activity of ultrashort peptides. In this study, the interactions of tetrapeptide BRBR-NH2 (BRBR) and pentapeptide BRBRB-NH2 (BRBRB) with dioleoylphosphatidylcholine/dioleoylphosphatidylglycerol (DOPC/DOPG) mixed model membrane were studied by molecular dynamics simulation to assess the role of biphenylalanine in promoting the antibacterial activity of ultrashort peptides. At low peptide concentrations, both peptides presented amphiphilic conformations; residues B of the pentapeptide approached the membrane faster than those of the tetrapeptide and made more contacts with the membrane; BRBRB exhibited stronger membrane affinity than BRBR. However, due to the low peptide concentrations, the effects of these two peptides on the membrane were not significantly different. At high peptide concentrations, the strong affinity of BRBRB made it have more interaction with membrane than BRBR and most residues B of BRBRB inserted into the membrane; BRBRB was more prone to aggregation and caused the membrane more disordered and thinner than BRBR. Hydrophobic residues often act as anchors in the antibacterial activity of ultrashort antimicrobial peptides. Adding a hydrophobic residue B to the C-terminal of BRBR could improve the ability of the peptide to "grasp" the membrane. At high peptide concentrations, the addition of residue B might enhance the antibacterial activity of the peptide. Thus, our results will be helpful in designing efficient antibacterial drugs.

Methylprednisolone pulse therapy promotes the differentiation of regulatory T cells by inducing the apoptosis of CD4+ T cells in patients with systemic lupus erythematosus.

OBJECTIVES: To investigate the differentiation of regulatory T cells (Tregs) induced by methylprednisolone (MP) pulse therapy in patients with Systemic Lupus Erythematosus (SLE). METHODS: We enrolled 30 patients with SLE and analyzed peripheral blood mononuclear cells (PBMCs) before and after MP pulse therapy. Peripheral Tregs, apoptosis of PBMCs subsets, and TGFß production by monocytes was quantified by flow cytometry. Proliferation and IFN-γ production of CD4+ T cells were measured. Furthermore, TGFß1 production by human monocyte-derived macrophages (HMDM) stimulated with MP-treated CD4+ T cells were quantified by ELISA. RESULTS: Peripheral Tregs was significantly increased after MP pulse therapy (6.76 ± 1.46% vs. 3.82 ± 1.02%, p < 0.01), with an expansion of Nrp1- induced Tregs (4.54 ± 0.46% vs. 1.75 ± 0.38%, p < 0.01). Proliferation and IFN-γ production of CD4+ T cells were significantly decreased after MP pulse therapy. MP pulse therapy induced CD4+ T cell apoptosis (early apoptosis, 26.34 ± 3.54% vs. 14.81 ± 2.89%, p < 0.01) and TGFß expression on monocytes (6.02% vs. 2.45%, p < 0.01). Furthermore, MP induced CD4+ T cell apoptosis in vitro, which stimulated HMDM to produce TGFß. Moreover, elevated TGFß level in supernatant from HMDM stimulated with MP-treated CD4+ T cells promoted Tregs differentiation. CONCLUSIONS: MP pulse therapy induces CD4+ T cell apoptosis, which promotes monocytes to produce TGFß and further facilitates Tregs differentiation. Newly-differentiated Tregs suppress proliferation and IFN-γ production of CD4+ T cells and contribute to immunoregulatory milieu after MP pulse therapy.

Cutaneous mucosa-associated lymphoid tissue lymphoma complicating Sjögren's syndrome: A case report and review of literature.

BACKGROUND: The association of Sjögren's syndrome (SS) and lymphoma is similar. Mucosa-associated lymphoid tissue (MALT) or extranodal marginal zone B-cell lymphoma was the most common lymphomatous histology in SS patients. MALT in SS patients is frequently located in the parotid gland, while MALT lymphoma of the skin with SS is an exceedingly rare entity that needs to be recognized. CASE SUMMARY: A 60-year-old woman presented with a 3-year history of progressive dry mouth associated with a 1-year history of enlarging cutaneous nodules. Physical examination revealed two hard subcutaneous nodules on her right lower leg. The results of Schirmer's test were positive, despite the absence of dry eyes. Labial salivary gland biopsy revealed lymphocytic infiltration and chronic inflammation with a focus score of 2. The patient was diagnosed with SS. She underwent resection of one cutaneous nodule, and histopathological analysis identified the nodule as MALT lymphoma. Her dry mouth symptoms improved, and the nodules decreased after 6 mo of treatment with hydroxychloroquine sulfate and chemotherapy (thalidomide, cyclophosphamide, and dexamethasone). CONCLUSION: Lymphoma is a severe complication of SS, shown by the reported unique case of cutaneous MALT lymphoma with SS.

Identification of a novel mutation in patients with type A insulin resistance syndrome.

INTRODUCTION: Type A insulin resistance syndrome is a rare type of congenital insulin resistance often caused by heterozygous mutations in the insulin receptor gene (INSR). The aim of this study is to explore the clinical and genetic characteristics of three patients with type A insulin resistance syndrome from two Chinese families. METHODS: The peripheral blood samples were collected from each family members. Whole-exome sequencing were performed on three patients. RESULTS: Patient #1 was diagnosed with hyperinsulinemia at the age of 11 years and presented with hirsutism, acanthosis nigricans, and polycystic ovaries by 13 years. A heterozygous c.3470A > G mutation in the INSR gene was identified in patient #1. Patient #2 was a 13-year-old girl who presented with insulin resistance, polycystic ovary, and hyperandrogenemia. A novel c.3601C > G INSR mutation was identified in patient #2. Co-segregated analysis showed that the c.3601C > G mutation was also found in her father, who had hyperinsulinemia and diabetes mellitus, which was consistent with autosomal dominant inheritance. SIFT and PolyPhen-2 predicted that the c.3470A > G and c.3601C > G mutations in INSR had damaging effects. CONCLUSION: Our study expands the genotypic and phenotypic spectrum of type A insulin resistance syndrome. Awareness of the clinical features coupled with INSR gene screening is key to early detection and active intervention.

Risk factors of disease flares in a Chinese lupus cohort with low-grade disease activity.

OBJECTIVE: Recurrent disease flare is one of the key problems in lupus patients. A Chinese Flare-Prevention Lupus Initiative Cohort (FLIC) was established. Risk factors of disease flare were evaluated accordingly. METHODS: Patients with low-grade disease activity (the Safety of Estrogens in Lupus Erythematosus National Assessment-SLE Disease Activity Index (SELENA-SLEDAI) =≤6, daily prednisone ≤20 mg, no British Isles Lupus Assessment Group A or no more than one B organ domain score) from January 2014 to August 2020 were included in the FLIC. Disease flares were defined by the modified SELENA--SLEDAI Flare Index. Low disease activity status (LDAS) and remission were also assessed. The cumulative flare rate was estimated by an event per 100 person-years analysis. Cox proportional hazards models were performed to identify risk factors of subsequent disease flares after adjusting clinical confounders. Survival was assessed with the Kaplan-Meier method. RESULTS: 448 eligible patients with low-grade disease activity were included in FLIC. During a mean follow-up of 30.4 months, 170 patients flared. The cumulative lupus flare rate was 22.2 events per 100 patient-years. Compared with patients without flare, those with lupus flares were taking more prednisone, had higher disease activity index and with less patients attained LDAS/remission at baseline. They also had higher rates of antiphospholipid antibodies (aPLs) and antiribosomal P antibody. Cox regression analysis confirmed that attainment of either LDAS or remission at baseline were independent protective factors against subsequent disease flare (LDAS but not in remission: HR 0.58, 95% CI 0.38~0.88; remission: HR 0.46, 95% CI 0.30~0.69), while aPL was a risk factor of lupus flares (HR 1.95, 95% CI 1.36~2.78). Kaplan-Meier curves indicated that attaining LDAS or remission and absence of aPL at baseline had the least flare risk. CONCLUSIONS: In our real-world cohort study, not attaining LDAS or remission at baseline and aPL positivity was associated with higher risk of disease flares in patients with low-grade SLE.