[Effects of periodontitis on bone and tryptophan metabolism of gut microbiota in estrogen-deficient mice]

Objective: To study the effects of periodontitis on bone and tryptophan metabolism of gut microbiota in the context of estrogen deficiency. Methods: Thirty-two female C57BL6/J mice were randomly divided into four groups based on table of random numbers (n=8 in each group): Sham group, in which mice were given sham surgery; Sham_Lig group, in which mice were given sham surgery and were induced to periodontitis by ligating the bilateral maxillary second molars with 5-0 silk threads at the fourth week; Ovx group, in which mice were given bilateral ovariectomy; Ovx_Lig group, in which mice were given bilateral ovariectomy and were induced to periodontitis at the fourth week. After 8 weeks of ligation, the mice of 4 groups were euthanized for collecting the samples of femur, tibia, mandible and skull. Those samples were scanned by micro-CT to measure the bone mineral density (BMD), bone volume versus total volume ratio (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th) and trabecular spacing (Tb.Sp). The cecum contents of 4 groups of mice were collected for gut microbiota 16S rRNA gene sequencing. The tryptophan and its metabolites in intestinal tracts were detected by liquid chromatography-mass spectrometry. Pearson correlation analysis was performed to analyze the correlation between the abundance of gut microbiota and the content of tryptophan and its metabolites. Results: Femur BMD [(82.23±3.97) mg/cm3], BV/TV [(9.25±1.37)%] and Tb.Th [(70.95±5.70) μm] in Ovx_Lig group were significantly lower than Ovx group [(96.30±3.76) mg/cm3 (P=0.004); (14.45±1.55)% (P=0.022) and (87.58±8.02) μm (P<0.001), respectively]. The β-diversity analysis of gut microbiota based on Bray-Curtis distance showed that samples of Ovx_Lig group and Ovx group were obviously grouped. Linear discriminant analysis effect size (LEfSe) showed that Alistipes was the representative genus in Ovx_Lig group. The relative abundance of Alistipes in Ovx_Lig group [(0.42±0.14)%] were significantly higher than that in Ovx group [(0.17±0.05)%] (t=4.45, P<0.001). Tryptophan metabolism analysis showed that the content of kynurenic acid [(531.12±158.60) ng/g] in Ovx_Lig group were significantly higher than that in Ovx group [(400.42±57.96) ng/g] (t=2.19, P=0.046). And the content of indole-3-carbaldehyde [(383.37±144.06) ng/g] in Ovx_Lig group were significantly lower than Ovx group [(701.72±141.93) ng/g] (t=4.45, P<0.001). Correlation analysis showed that relative abundance of Alistipes was positively correlated with kynurenic acid (r=0.32, P=0.088), while negatively correlated with indole-3-carbaldehyde (r=-0.32, P=0.088). Conclusions: Periodontitis can induce bone destruction of femur in estrogen-deficient mice, the mechanism of which may be related to Alistipes in gut and the tryptophan metabolites kynurenic acid and indole-3-carbaldehyde.

A landscape of gene expression regulation for synovium in arthritis

The synovium is an important component of any synovial joint and is the major target tissue of inflammatory arthritis. However, the multi-omics landscape of synovium required for functional inference is absent from large-scale resources. Here we integrate genomics with transcriptomics and chromatin accessibility features of human synovium in up to 245 arthritic patients, to characterize the landscape of genetic regulation on gene expression and the regulatory mechanisms mediating arthritic diseases predisposition. We identify 4765 independent primary and 616 secondary cis-expression quantitative trait loci (cis-eQTLs) in the synovium and find that the eQTLs with multiple independent signals have stronger effects and heritability than single independent eQTLs. Integration of genome-wide association studies (GWASs) and eQTLs identifies 84 arthritis related genes, revealing 38 novel genes which have not been reported by previous studies using eQTL data from the GTEx project or immune cells. We further develop a method called eQTac to identify variants that could affect gene expression by affecting chromatin accessibility and identify 1517 regions with potential regulatory function of chromatin accessibility. Altogether, our study provides a comprehensive synovium multi-omics resource for arthritic diseases and gains new insights into the regulation of gene expression.

[Research advances in imaging techniques related to the diagnosis of pneumoconiosis]

Occupational pneumoconiosis (hereinafter referred to as pneumoconiosis) is the most harmful occupational disease in China. According to the current standard GBZ 70-2015 Diagnosis of Occupational Pneumoconiosis, pneumoconiosis is mainly diagnosed and staged by high kilovolt or digital radiography. Chest radiography in pneumoconiosis is the most widely studied and mature imaging technique in the diagnosis of pneumoconiosis. However, this technique has some limitations in the screening of some early pneumoconiosis and occupational health examination, and there is a certain risk of missed diagnosis and misdiagnosis. With the continuous development of imaging examination technology, computed tomography, magnetic resonance imaging, positron emission tomography-computed tomography and artificial intelligence technology as auxiliary imaging examination methods have shown different diagnostic values in the research of auxiliary diagnosis of pneumoconiosis. This paper summarizes the advantages and problems in the application of various kinds of imaging techniques, which provides a direction for the future research of imaging techniques related to the diagnosis of pneumoconiosis.

[Impact of different diagnostic criteria for assessing mild micro-hepatic encephalopathy in liver cirrhosis: an analysis based on a prospective, multicenter, real-world study]

Objective: To compare the differences in the prevalence of mild micro-hepatic encephalopathy (MHE) among patients with cirrhosis by using the psychometric hepatic encephalopathy score (PHES) and the Stroop smartphone application (Encephal App) test. Methods: This prospective, multi-center, real-world study was initiated by the National Clinical Medical Research Center for Infectious Diseases and the Portal Hypertension Alliance and registered with International ClinicalTrials.gov (NCT05140837). 354 cases of cirrhosis were enrolled in 19 hospitals across the country. PHES (including digital connection tests A and B, digital symbol tests, trajectory drawing tests, and serial management tests) and the Stroop test were conducted in all of them. PHES was differentiated using standard diagnostic criteria established by the two studies in China and South Korea. The Stroop test was evaluated based on the criteria of the research and development team. The impact of different diagnostic standards or methods on the incidence of MHE in patients with cirrhosis was analyzed. Data between groups were differentiated using the t-test, Mann-Whitney U test, and χ (2) test. A kappa test was used to compare the consistency between groups. Results: After PHES, the prevalence of MHE among 354 cases of cirrhosis was 78.53% and 15.25%, respectively, based on Chinese research standards and Korean research normal value standards. However, the prevalence of MHE was 56.78% based on the Stroop test, and the differences in pairwise comparisons among the three groups were statistically significant (kappa = -0.064, P < 0.001). Stratified analysis revealed that the MHE prevalence in three groups of patients with Child-Pugh classes A, B, and C was 74.14%, 83.33%, and 88.24%, respectively, according to the normal value standards of Chinese researchers, while the MHE prevalence rates in three groups of patients with Child-Pugh classes A, B, and C were 8.29%, 23.53%, and 38.24%, respectively, according to the normal value standards of Korean researchers. Furthermore, the prevalence rates of MHE in the three groups of patients with Child-Pugh grades A, B, and C were 52.68%, 58.82%, and 73.53%, respectively, according to the Stroop test standard. However, among the results of each diagnostic standard, the prevalence of MHE showed an increasing trend with an increasing Child-Pugh grade. Further comparison demonstrated that the scores obtained by the number connection test A and the number symbol test were consistent according to the normal value standards of the two studies in China and South Korea (Z = -0.982, -1.702; P = 0.326, 0.089), while the other three sub-tests had significant differences (P < 0.001). Conclusion: The prevalence rate of MHE in the cirrhotic population is high, but the prevalence of MHE obtained by using different diagnostic criteria or methods varies greatly. Therefore, in line with the current changes in demographics and disease spectrum, it is necessary to enroll a larger sample size of a healthy population as a control. Moreover, the establishment of more reliable diagnostic scoring criteria will serve as a basis for obtaining accurate MHE incidence and formulating diagnosis and treatment strategies in cirrhotic populations.

[Effects of the kynurenine pathway on the osteogenic differentiation of periodontal ligament stem cells]

Objective: To explore the effect of kynurenine pathway on the osteogenic differentiation of periodontal ligament stem cells (PDLSC). Methods: Unstimulated saliva samples were collected from 19 patients with periodontitis (periodontitis group) and 19 periodontally healthy individuals (health group) in Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Nanjing University from June to October of 2022. Contents of kynurenine and the metabolites in saliva samples were analyzed by ultra-performance liquid chromatography-tandem mass spectrometry. The expressions of indoleamine 2, 3-dioxygenase (IDO) and aryl hydrocarbon receptor (AhR) were further detected by immunohistochemistry in gingival tissues. The PDLSC used in this study were isolated from extracted teeth for orthodontic treatment in Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Nanjing University from July to November of 2022. Experiments were then conducted using the cells by incubating with (kynurenine group) or without kynurenine (control group) in vitro. Seven days later, alkaline phosphatase (ALP) staining and assays of ALP activity were performed. Real-time fluorescence quantitative PCR (RT-qPCR) was utilized to detect the expressions of osteogenic related genes ALP, osteocalcin (OCN), runt-related transcription factor 2 (RUNX2), collagen type-Ⅰ (COL-Ⅰ) as well as the kynurenine pathway-associated genes AhR, cytochrome P450 family (CYP) 1A1, CYP1B1. Western blotting was used to detect the expression levels of RUNX2, osteopontin (OPN) and AhR proteins on day 10 and alizarin red staining was performed to observe the formation of mineral nodules on day 21 in control group and kynurenine group. Results: Salivary concentrations of kynurenine [8.26 (0, 19.60) nmol/L] and kynurenic acid [11.4 (3.34, 13.52) nmol/L] were significantly higher in the periodontitis group than in the health group [0.75(0, 4.25) nmol/L, 1.92(1.34, 3.88) nmol/L] (Z=-2.84, P=0.004; Z=-3.61, P<0.001). The expression levels of IDO (18.33±2.22) and AhR (44.14±13.63) in gingival tissues of periodontitis patients were significantly higher than that of the health group (12.21±2.87, 15.39±5.14) (t=3.38, P=0.015; t=3.42, P=0.027). In vitro, the ALP activity of PDLSC in the kynurenine group (291.90±2.35) decreased significantly compared with the control group (329.30±19.29) (t=3.34, P=0.029). The mRNA expression levels of ALP, OCN and RUNX2 in the kynurenine group (0.43±0.12, 0.78±0.09, 0.66±0.10) were decreased compared with the control group (1.02±0.22, 1.00±0.11, 1.00±0.01) (t=4.71, P=0.003; t=3.23, P=0.018; t=6.73, P<0.001), while the levels of AhR and CYP1A1 were increased in the kynurenine group (1.43±0.07, 1.65±0.10) compared with those in the control group (1.01±0.12, 1.01±0.14) (t=5.23, P=0.006; t=6.59, P<0.001). No significant difference was observed in COL-Ⅰ and CYP1B1 mRNA levels between groups. The protein levels of OPN, RUNX2 (0.82±0.05, 0.87±0.03) were reduced and that of AhR (1.24±0.14) was increased in the kynurenine group compared with those in the control group (1.00±0.00, 1.00±0.00, 1.00±0.00) (t=6.79, P=0.003; t=7.95, P=0.001; t=3.04, P=0.039). Conclusions: Over-activated kynurenine pathway in periodontitis patients can promote upregulation of AhR and suppress the osteogenic differentiation of PDLSC.

Enhancer variants on chromosome 2p14 regulating SPRED2 and ACTR2 act as a signal amplifier to protect against rheumatoid arthritis

Genome-wide association studies (GWASs) have repeatedly reported multiple non-coding single-nucleotide polymorphisms (SNPs) at 2p14 associated with rheumatoid arthritis (RA), but their functional roles in the pathological mechanisms of RA remain to be explored. In this study, we integrated a series of bioinformatics and functional experiments and identified three intronic RA SNPs (rs1876518, rs268131, and rs2576923) within active enhancers that can regulate the expression of SPRED2 directly. At the same time, SPRED2 and ACTR2 influence each other as a positive feedback signal amplifier to strengthen the protective role in RA by inhibiting the migration and invasion of rheumatoid fibroblast-like synoviocytes (FLSs). In particular, the transcription factor CEBPB preferentially binds to the rs1876518-T allele to increase the expression of SPRED2 in FLSs. Our findings decipher the molecular mechanisms behind the GWAS signals at 2p14 for RA and emphasize SPRED2 as a potential candidate gene for RA, providing a potential target and direction for precise treatment of RA.

[Multidisciplinary regenerative treatment and mechanisms for rescuing a severe calciphylaxis patient with human amnion-derived mesenchymal stem cells]

Calciphylaxis is a rare disease with severe pain and high-mortality due to cutaneous ischemic necrosis and infection that currently lacks proved effective therapies. The occurrence of calciphylaxis in end stage kidney disease (ESKD) patients is known as calcific uremic arteriolopathy (CUA), which is characterized histologically by dermal microvessel calcification, intimal fibroplasia and microthrombosis. Here we innovatively treated a severe CUA patient with human amnion-derived mesenchymal stem cells (hAMSCs). A 34-year-old uremic woman was presented with progressive, painful malodorous ulcers in buttocks and mummified lower limbs. Skin pathological features supported the diagnosis of calciphylaxis. The patient was refractory to conventional multidisciplinary symptomatic therapies. With the approval of our hospital ethics committee, she was treated with hAMSCs including intravenous and local intramuscular injection, and external application of hAMSC culture supernatant to the wound area. During 15-month follow-up, the patient had regeneration of skin and soft tissues, with improved blood biochemical, inflammatory, mineral and bone metabolic indices and immunoregulation effects. After 15-month hAMSC treatment, the score of pain visual analog scale (VAS) decreased from 10 to 0, Bates-Jensen wound assessment tool (BWAT) score decreased from 65 to 13, and wound-quality of life (Wound-QoL) questionnaire score decreased from 68 to 0. We propose that hAMSC treatment is promising for CUA patients. The therapy is potentially involved in the multiple beneficial effects of inhibiting vascular calcification, stimulating angiogenesis and myogenesis, modulating adverse inflammatory and immunologic responses, promoting re-epithelialization and restoring skin integrity.

[Effects of salivary microbiota on tryptophan-aryl hydrocarbon receptor signaling axis in mice with periodontitis]

Objective: To study the effects of salivary microbiota in patients with periodontitis on the tryptophan-aryl hydrocarbon receptor (AhR) signaling axis in mice with periodontitis and to provide theoretical basis as well as new ideas for the influences of periodontitis on systemic metabolism. Methods: Salivary microbiota of 12 healthy individuals and 14 patients with periodontitis were collected in Nanjing Stomatological Hospital, Medical School of Nanjing University from June to December of 2020. According to the random number table method, twenty-four mice were randomly divided into three groups: Sham group (control group), P group (periodontitis patients' salivary microbiota group) and H group (periodontal healthy individuals' salivary microbiota group). The maxillary second molars of all mice were treated with silk thread ligation to induce periodontitis. Phosphate buffer as well as salivary microbiota of periodontal healthy individuals and periodontitis patients were gavaged into periodontitis mice for 2 weeks. The expression of inflammatory factors in mice serum were detected by enzyme linked immunosorbent assay, and the expression of tryptophan and indole metabolites in intestinal tract and serum were detected by liquid chromatography-mass spectrometry. The expression of AhR in intestinal tract of mice was detected by immunohistochemistry and quantitative real time-PCR while gut microbiota constitution was detected by 16S rRNA gene sequencing. The remaining saliva samples of periodontitis patients and periodontal healthy individuals were applied to detect the expression of tryptophan and indole metabolites themselves. Results: The salivary microbiota of periodontitis patients could induce the expression of interleukin-1β [P group: (162.38±39.46) pg/ml, H group: (82.83±20.01) pg/ml; t=4.40, P=0.001) and tumor necrosis factor-α [P group: (361.16±123.90) pg/ml, H group: (191.66±106.87) pg/ml; t=2.54, P=0.030) in serum of periodontitis mice, and reduce the expression of AhR in colon (P group: 1.18±0.05, H group:1.83±0.47; t=3.09, P=0.015) and ileum (P group: 0.80±0.13, H group: 1.18±0.11; t=4.93, P=0.001). After gavage of salivary microbiota of periodontitis patients to the mice, tryptophan (P group: (18.1±3.8)×10⁷, H group: (26.6±6.6)×10⁷; t=2.49, P=0.037] and indole lactic acid [P group: (1.9±0.7)×10⁷, H group: (3.7±0.6)×10⁷; t=4.49, P=0.002) in serum of periodontitis mice were significantly decreased, but was relatively disorder in intestinal tract. However, the expressions of tryptophan and indole metabolites in saliva of periodontitis patients were higher than those of periodontal healthy individuals. There were significant differences in indole propionic acid [P group: (1 239.39±818.72) nmol/L, H group: (56.96±38.33) nmol/L; t=2.83, P=0.022]. What we find noteworthy was that the expressions of indolelactic acid metabolism in saliva, serum and intestinal were consistent, and salivary microbiota of periodontitis patients could reduce the relative abundance of indolelactic acid-producing bacteria in the gut, suggesting that the salivary microbiota of periodontitis patients might affect the expression of AhR through gut microbiota disorder and indolelactic acid downregulation. Conclusions: Salivary microbiota in patients with periodontitis may affect the systemic inflammatory state through down-regulating the expression of tryptophan-AhR signal axis.

Individualized pathway activity algorithm identifies oncogenic pathways in pan-cancer analysis

Background

Accumulative evidences have shown that dysregulation of biological pathways contributed to the initiation and progression of malignant tumours. Several methods for pathway activity measurement have been proposed, but they are restricted to making comparisons between groups or sensitive to experimental batch effects.

Methods

We introduced a novel method for individualized pathway activity measurement (IPAM) that is based on the ranking of gene expression levels in individual sample. Taking advantage of IPAM, we calculated the pathway activity of 318 pathways from KEGG database in the 10528 tumour/normal samples of 33 cancer types from TCGA to identify characteristic dysregulated pathways among different cancer types.

Findings

IPAM precisely quantified the level of activity of each pathway in pan-cancer analysis and exhibited better performance in cancer classification and prognosis prediction over five widely used tools. The average ROC-AUC of cancer diagnostic model using tumour-educated platelets (TEPs) reached 92.84%, suggesting the potential of our algorithm in early diagnosis of cancer. We identified several pathways significantly deregulated and associated with patient survival in a large fraction of cancer types, such as tyrosine metabolism, fatty acid degradation, cell cycle, p53 signalling pathway and DNA replication. We also confirmed the dominant role of metabolic pathways in cancer pathway dysregulation and identified the driving factors of specific pathway dysregulation, such as PPARA for branched-chain amino acid metabolism and NR1I2, NR1I3 for fatty acid metabolism.

Interpretation

Our study will provide novel clues for understanding the pathological mechanisms of cancer, ultimately paving the way for personalized medicine of cancer.

Funding

A full list of funding can be found in the Acknowledgements section.

[Establishment of morphological reference values for the differential count of white blood cells in peripheral blood smear, as well as nucleated cells and megakaryocytes in bone marrow smear]

Objective: To establish the morphological reference values for the differential count of white blood cells in peripheral blood smear as well as nucleated cells and megakaryocytes in bone marrow smear. Methods: From April 2012 to June 2020, 4 221 healthy donors for hematopoietic stem cell transplantation in Hebei Yanda Lu Daopei Hospital were selected. The median age was 36 (3-72) years old, including 2 520 males and 1 701 females. They were divided into four groups according to age: children group, with age≤14 years old [n=334, 11 (3-14) years old], youth group, with age >14 years old and <45 years old [n=2 855, 33 (15-44) years old], middle-aged adult group, with age ≥45 years old and < 60 years old [n=929, 49 (45-59) years old], and older adult group, with age ≥60 years old [n=103, 62 (60-72) years old]. Gender subgroups were established in each age group. According to different hematopoietic characteristics, the children group were divided into two subgroups: children group 1 [n=48, 6 (3-7) years old] and children group 2 [n=286, 11 (8-14) years old]. According to the clinical routine, 100 white blood cells in peripheral blood, 200 nucleated cells in bone marrow, and cell numbers/4.5 cm² for megakaryocytes were classified and counted. The results of cell count in different age and gender groups were compared, and the reference values of morphological classification were established for different groups with statistical or clinical significance. Results: Due to the existence of statistically significant differences between children and adult groups and different gender subgroups in adults (all P<0.05), the reference values were established for children group and adult gender subgroups. The counts of segmented neutrophils and lymphocytes in peripheral blood were 46.65(43.97-49.32)% and 44.00(10.60-65.10)% in children group 1, 50.73(49.50-51.96)% and 39.55 (38.36-40.74)% in children group 2, and 57.00 (39.00-75.23) % and 33.00 (17.00-52.00) % in adult group, respectively. Bone marrow segmented neutrophils, orthochromatic erythroblasts, and mature lymphocytes were 11.54 (10.68-12.41)%, 14.20 (13.19-15.21)%, and 23.99 (22.06-25.92)% in children group 1, 12.50 (7.00-21.50)%, 15.00(9.50-25.50)%, and 21.02 (20.24-21.81)% in children group 2, 13.50 (7.50-21.00)%, 16.50 (10.50-26.00)%, and 15.50 (7.50-26.00)% in adult male group, and 14.50 (8.00-24.50)%, 14.50 (9.00-23.00)%, and 17.50 (8.50-29.00)% in adult female group, respectively. The myelopoiesis/erythropoiesis ratio in children group, adult male group and adult female group was 1.86∶1 (1.14∶1-3.23∶1), 1.96∶1 (1.12∶1-3.19∶1), 2.22∶1 (1.30∶1-3.69∶1), respectively. The numbers of granular megakaryocytes and thromocytogenic megakaryocytes were 138 (25-567) cells/4.5cm² and 86 (13-328) cells/4.5 cm² in children group, and 92 (13-338) cells/4.5 cm² and 38 (3-162) cells/4.5 cm² in adult group, respectively. Conclusion: The morphological reference values for the differential count of white blood cells in peripheral blood smear as well as nucleated cells and megakaryocytes in bone marrow smear are successfully established, which is helpful to improve the application of morphological examination in disease screening, diagnosis and monitoring.

Transcriptome-wide association study identifies multiple genes and pathways associated with thyroid function

Thyroid dysfunction is a common endocrine disease measured by thyroid-stimulating hormone (TSH) level. Although more than 70 genetic loci associated with TSH have been reported through genome-wide association studies (GWASs), the variants can only explain a small fraction of the thyroid function heritability. To identify novel candidate genes for thyroid function, we conducted the first large-scale transcriptome-wide association study (TWAS) for thyroid function using GWAS-summary data for TSH levels in up to 119 715 individuals combined with pre-computed gene expression weights of six panels from four tissue types. The candidate genes identified by TWAS were further validated by TWAS replication and gene expression profiles. We identified 74 conditionally independent genes significantly associated with thyroid function, such as PDE8B (P = 1.67 × 10-282), PDE10A (P = 7.61 × 10-119), NR3C2 (P = 1.50 × 10-92), and CAPZB (P = 3.13 × 10-79). After TWAS replication using UKBB datasets, 26 genes were replicated for significant associations with thyroid-relevant diseases/traits. Among them, 16 gene were causal for their associations to thyroid-relevant diseases/traits and further validated in differential expression analyses, including two novel genes (MFSD6 and RBM47) that did not implicate in previous GWASs. Enrichment analyses detected several pathways associated with thyroid function, such as the cAMP signaling pathway (P = 7.27 × 10-4), hemostasis (P = 3.74 × 10-4), and platelet activation, signaling, and aggregation (P = 9.98 × 10-4). Our study identified multiple candidate genes and pathways associated with thyroid function, providing novel clues for revealing the genetic mechanisms of thyroid function and disease.

[Related factors for hyperkalemia and its recurrence in maintenance hemodialysis patients]

Objective: To investigate the prevalence of hyperkalemia and recurrent hyperkalemia in maintenance hemodialysis patients, and identify the related factors. Methods: The general information and clinical data of maintenance hemodialysis patients in the hemodialysis center of the First Affiliated Hospital of Nanjing Medical University from January to December 2020 were collected. According to the level of serum potassium, the patients were divided into normokalemia group and hyperkalemia group. Patients in the hyperkalemia group were further divided into single hyperkalemia group and recurrent hyperkalemia group according to the number of occurrences of hyperkalemia. Then, the prevalence of different serum potassium abnormalities and the related factors were explored. Results: Among the 352 patients included in the final analysis, 129 cases (36.6%) were in the normokalemia group [mean age: (62±15) years, 99 males] and 223 cases (63.4%) were in the hyperkalemia group [mean age: (60±14) years, 153 males]. Multivariate logistic regression analysis demonstrated that, compared with the normokalemia group, night-time dialysis (OR=4.012, 95%CI: 1.519-10.601, P=0.005), concurrent diabetes (OR=1.947, 95%CI: 1.148-3.304, P=0.013) and the number of serum potassium tested before hemodialysis (OR=1.561, 95%CI:1.292-1.885, P<0.001) were independent risk factors for hyperkalemia. Among 223 patients with hyperkalemia, 78 cases (35.0%) were in single hyperkalemia group and 145 cases (65.0%) were in recurrent hyperkalemia group. Multivariate logistic regression analysis demonstrated that, serum calcium (OR=21.885, 95%CI: 3.740-128.077, P=0.001), peak value of serum potassium before hemodialysis (OR=63.157, 95%CI: 25.265-157.876, P<0.001) and the number of serum potassium tested before hemodialysis (OR=1.814, 95%CI: 1.378-2.388, P<0.001) were the independent risk factors for the recurrence of hyperkalemia. Conclusions: The prevalence of hyperkalemia is high in maintenance hemodialysis patients, especially in those with diabetes or night-time dialysis. It is necessary to monitor serum potassium regularly. In addition, high serum calcium and peak value of serum potassium before hemodialysis are related factors for recurrent hyperkalemia.

Survival of itinerant excitations and quantum spin state transitions in YbMgGaO4 with chemical disorder

A recent focus of quantum spin liquid (QSL) studies is how disorder/randomness in a QSL candidate affects its true magnetic ground state. The ultimate question is whether the QSL survives disorder or the disorder leads to a “spin-liquid-like” state, such as the proposed random-singlet (RS) state. Since disorder is a standard feature of most QSL candidates, this question represents a major challenge for QSL candidates. YbMgGaO₄, a triangular lattice antiferromagnet with effective spin-1/2 Yb³⁺ions, is an ideal system to address this question, since it shows no long-range magnetic ordering with Mg/Ga site disorder. Despite the intensive study, it remains unresolved as to whether YbMgGaO₄ is a QSL or in the RS state. Here, through ultralow-temperature thermal conductivity and magnetic torque measurements, plus specific heat and DC magnetization data, we observed a residual κ₀/T term and series of quantum spin state transitions in the zero temperature limit for YbMgGaO₄. These observations strongly suggest that a QSL state with itinerant excitations and quantum spin fluctuations survives disorder in YbMgGaO₄.

It remains an open question as to whether the quantum spin liquid state survives material disorder, or is replaced by some spin-liquid like state. Here, Rao et al succeed in resolving a resolving a κ₀/T residual in the thermal conductivity of YbMgGaO₄ strongly suggesting the survival of the quantum spin liquid state.

[Control study of chest CT imaging features of aluminosis and silicosis patients]

Objective: To understand the chest CT features of aluminosis caused by alumina and to improve the understanding of the imaging findings of alumina pneumoconiosis. Methods: The chest CT findings of 17 cases of alumina-induced pneumoconiosis and 30 cases of silicosis (the control group) diagnosed in Zibo Occupational Disease Prevention Hospital from April 2015 to July 2020 were analyzed retrospectively. The characteristics of fibrosis of the two kinds of pneumoconiosis and the incidence of size, density, distribution, tractive bronchiectasis, pleural thickening and interlobular septal thickening of pneumoconiosis nodules were compared. Results: Alumina pneumoconiosis showed nodules with thickened interlobular septal of 66.67% (12/18) , honeycomb lung of 22.22% (4/18) , ground glass shadow of 61.11% (11/18) , simple nodules of 11.11% (2/18) , and no fusion mass. In the control group, the long-line fibrosis of nodules with thickened interlobular septal were 16.67% (5/30) , 6.67% (2/30) with honeycomb lung and ground glass density shadow, 23.33% (7/30) with fusion mass and 53.33% (16/30) with simple nodule. There were significant differences in CT findings of nodules with thickened interlobular septal, ground glass density shadow, fused mass and simple nodules between the two groups (P<0.05) . The interstitial beaded nodules were seen in 18 cases of alumina pneumoconiosis, 50.00% (9/18) of them were beaded nodules, 61.33% (46/75) of low density nodules and 38.89% (7/18) of central lobular nodules were seen in alumina pneumoconiosis. The average width of nodules was (1.29±0.38) mm. Central lobular nodules were seen in all 30 cases of silicosis, 10.00% (3/30) were mainly beaded nodules, low density nodules were 36.29% (90/248) , and the average width diameter of nodules was (1.85±0.58) mm. There were significant differences between the two groups (P<0.05) . Alumina pneumoconiosis was often accompanied by traction bronchiectasis, pleural thickening and interlobular septal thickening (11, 18, 17 cases, 61.11%, 100.00%, 94.44%) , compared with the control group (9, 18, 18 cases, 30.00%, 60.00%, 60.00%) . The differences were statistically significant (P<0.05) . The maximum CT value of noncalcified mediastinal lymphnodes in alumina pneumoconiosis was (103.43±26.33) HU, which was higher than that of the control group[ (75.22±16.70) HU], and the difference was statistically significant (P<0.05) . Conclusion: Alumina pneumoconiosis chest CT shows slightly low-density beaded nodules, thickened interlobular septal, and pulmonary interstitial fibrosis of ground-glass shadows, mostly combines with stretched bronchiectasis, thickened pleura, and mediastinum increased lymph node density.

Double Superconducting Dome and Triple Enhancement of T_{c} in the Kagome Superconductor CsV_{3}Sb_{5} under High Pressure

CsV_{3}Sb_{5} is a newly discovered Z_{2} topological kagome metal showing the coexistence of a charge-density-wave (CDW)-like order at T^{*}=94  K and superconductivity (SC) at T_{c}=2.5  K at ambient pressure. Here, we study the interplay between CDW and SC in CsV_{3}Sb_{5} via measurements of resistivity, dc and ac magnetic susceptibility under various pressures up to 6.6 GPa. We find that the CDW transition decreases with pressure and experience a subtle modification at P_{c1}≈0.6-0.9  GPa before it vanishes completely at P_{c2}≈2  GPa. Correspondingly, T_{c}(P) displays an unusual M-shaped double dome with two maxima around P_{c1} and P_{c2}, respectively, leading to a tripled enhancement of T_{c} to about 8 K at 2 GPa. The obtained temperature-pressure phase diagram resembles those of unconventional superconductors, illustrating an intimated competition between CDW-like order and SC. The competition is found to be particularly strong for the intermediate pressure range P_{c1}≤P≤P_{c2} as evidenced by the broad superconducting transition and reduced superconducting volume fraction. The modification of CDW order around P_{c1} has been discussed based on the band structure calculations. This work not only demonstrates the potential to raise T_{c} of the V-based kagome superconductors, but also offers more insights into the rich physics related to the electron correlations in this novel family of topological kagome metals.

Modeling circRNA expression pattern with integrated sequence and epigenetic features demonstrates the potential involvement of H3K79me2 in circRNA expression

MOTIVATION

CircRNAs are an abundant class of non-coding RNAs with widespread, cell-/tissue-specific patterns. Previous work suggested that epigenetic features might be related to circRNA expression. However, the contribution of epigenetic changes to circRNA expression has not been investigated systematically. Here, we built a machine learning framework named CIRCScan, to predict circRNA expression in various cell lines based on the sequence and epigenetic features.

RESULTS

The predicted accuracy of the expression status models was high with area under the curve of receiver operating characteristic (ROC) values of 0.89-0.92 and the false-positive rates of 0.17-0.25. Predicted expressed circRNAs were further validated by RNA-seq data. The performance of expression-level prediction models was also good with normalized root-mean-square errors of 0.28-0.30 and Pearson's correlation coefficient r over 0.4 in all cell lines, along with Spearman's correlation coefficient ρ of 0.33-0.46. Noteworthy, H3K79me2 was highly ranked in modeling both circRNA expression status and levels across different cells. Further analysis in additional nine cell lines demonstrated a significant enrichment of H3K79me2 in circRNA flanking intron regions, supporting the potential involvement of H3K79me2 in circRNA expression regulation.

AVAILABILITY AND IMPLEMENTATION

The CIRCScan assembler is freely available online for academic use at https://github.com/johnlcd/CIRCScan.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Ancestry Inference Using the ForenSeqTM DNA Signature Prep Kit

Objective To evaluate the effect of 56 ancestry informative single nucleotide polymorphism （aiSNP） genetic markers in the ForenSeq^TM DNA Signature Prep Kit on ancestry inference. Methods A total of 85 samples from five populations including Hebei Han population, Inner Mongolia autonomous region Mongolian population, Tibet autonomous region Tibetan population, Xinjiang Uygur autonomous region Uygur population and Nigerian population were collected. The library was constructed with the ForenSeq^TM DNA Signature Prep Kit and sequencing was performed based on the MiSeq FGx Forensic Genomics System. Using universal analysis software （UAS） of ForenSeq^TM, principal component analysis （PCA）, Structure and likelihood ratio method was used on the genotyping data of 56 aiSNP markers, respectively, and the genetic relationships between populations and inference of the origin of ancestors were analyzed. Results Among the five populations tested, the four ethnic populations in China （Hebei Han population, Inner Mongolia autonomous region Mongolian population, Tibet autonomous region Tibetan population and Xinjiang Uygur autonomous region Uygur population） could be significantly distinguished from Nigerian population. Xinjiang Uygur autonomous region Uygur individuals were shown as having mixed origins of ancestors and could be distinguished from the other three Chinese populations. However, the other three populations in China （Hebei Han population, Inner Mongolia autonomous region Mongolian population and Tibet autonomous region Tibetan population） could not be effectively distinguished by the system. Conclusion The 56 aiSNP markers in the ForenSeq^TM DNA Signature Prep Kit can make accurate ancestry inference from the intercontinental level, but it is not yet able to distinguish between Chinese subpopulations.

An Allele-Specific Functional SNP Associated with Two Systemic Autoimmune Diseases Modulates IRF5 Expression by Long-Range Chromatin Loop Formation

Both systemic lupus erythematosus (SLE) and systemic sclerosis (SSc) are autoimmune diseases sharing similar genetic backgrounds. Genome-wide association studies have constantly disclosed numerous genetic variants conferring to both disease risks at 7q32.1, but the functional mechanisms underlying them are still largely unknown. Through a series of bioinformatics and functional analyses, we prioritized a potential independent functional single-nucleotide polymorphism (rs13239597) within TNPO3 promoter region, residing in a putative enhancer element and validated that IRF5 is the distal target gene (∼118 kb) of rs13239597, which is a key regulator involved in pathogenic autoantibody dysregulation, increasing risk of both SLE and SSc. We experimentally validated the long-range chromatin interactions between rs13239597 and IRF5 using chromosome conformation capture assay. We further demonstrated that rs13239597-A acted as an allele-specific enhancer regulating IRF5 expression, independently of TNPO3 by using dual-luciferase reporter assays and CRISPR-Cas9. Particularly, the transcription factor EVI1 could preferentially bind to rs13239597-A allele and increase the enhancer activity to regulate IRF5 expression. Taken together, our results uncovered a mechanistic insight of a noncoding functional variant acting as an allele-specific distal enhancer to directly modulate IRF5 expression, which might obligate in understanding of complex genetic architectures of SLE and SSc pathogenesis.

Full Sibling Testing Based on NGS-SNP Genotyping Method and IBS Strategy

Abstract

Objective To evaluate the effectiveness of single nucleotide polymorphism （SNP） genoty-ping in combination with identity by state （IBS） strategy in full sibling testing. Methods Thirty-five blood samples were collected from a four-generation family. Ninety autosomal SNPs were genotyped using Precision ID Identity Panel. The distribution of IBS scores for full siblings and other relationships were calculated and compared. The relationships were determined using Fisher discriminant function and threshold method, respectively. Results Based on family members and previous research, 44, 30, 111, 71 and 1 000 pairs of full siblings （FS）, grandparent-grandchild （GG）, uncle/aunt-nephew/niece （UN）, first cousins （FC） and unrelated individuals （UI） were obtained, respectively. The average IBS scores were 148, 130, 132, 124 and 120, respectively. Except for the GG and UN pairs, the distribution differences among the other relationships had statistical significance （P<0.05）. The false rates of Fisher discriminant function to determine relationships were 1.3%, 22.3%, 17.0% and 38.7% for FS, GG, UN and FC, respectively. Based on the simulation data, the thresholds t₁=128 and t₂=141 were recommended to determine full sibling relationships （the false rate ≤0.05%）. Conclusion The 90 SNP genetic markers included in the Precision ID Identity Panel meet the testing requirements for full sibling relationships. The threshold method based on IBS has a relatively lower false rate and is more flexible.

Low-level serum miR-24-2 is associated with the progression of colorectal cancer

BACKGROUND

colorectal cancer (CRC) is the second leading cause of cancer and cancer-related death in the world. Noninvasive biomarkers for early diagnosis of CRC are highly demanded.

OBJECTIVE

The up-regulation of specific microRNAs (miRNAs) in serum has been considered a promising biomarker of CRC and miR-24-2 may be a potential biomarker in the diagnosis the progression of CRC.

METHODS

Sixty-eighty healthy subjects and 228 CRC patients were divided into six groups: control group, CRC 0, CRC I, CRC II, CRC III, CRC IV and CRC V. Serum level of miR-24-2 was measured by real-time qPCR. Serum lipid profiles and oxidative-related molecules were also measured.

RESULTS

Serum levels of miR-24-2 in CRC patients were significantly higher than healthy subjects (p< 0.05). In addition, the expression level of the miR-24-2 was decreased with the progression of CRC and reached the lowest level in CRC V. Spearman Rank Correlation analysis showed that miR-24-2 level was negatively related to the levels of superoxide dismutase (SOD) and reduced glutathione (GSH), aspartate transaminase (AST), alanine transaminase (ALT), cholesterol and triglyceride (p< 0.05).

CONCLUSIONS

Serum miR-24-2 is a potential negative biomarker in the diagnosis of the progression of CRC patients and associated with biochemical indices.

Multiple Functional Variants at 13q14 Risk Locus for Osteoporosis Regulate RANKL Expression Through Long-Range Super-Enhancer

RANKL is a key regulator involved in bone metabolism, and a drug target for osteoporosis. The clinical diagnosis and assessment of osteoporosis are mainly based on bone mineral density (BMD). Previous powerful genomewide association studies (GWASs) have identified multiple intergenic single-nucleotide polymorphisms (SNPs) located over 100 kb upstream of RANKL and 65 kb downstream of AKAP11 at 13q14.11 for osteoporosis. Whether these SNPs exert their roles on osteoporosis through RANKL is unknown. In this study, we conducted integrative analyses combining expression quantitative trait locus (eQTL), genomic chromatin interaction (high-throughput chromosome conformation capture [Hi-C]), epigenetic annotation, and a series of functional assays. The eQTL analysis identified six potential functional SNPs (rs9533090, rs9594738, r8001611, rs9533094, rs9533095, and rs9594759) exclusively correlated with RANKL gene expression (p < 0.001) at 13q14.11. Co-localization analyses suggested that eQTL signal for RANKL and BMD-GWAS signal shared the same causal variants. Hi-C analysis and functional annotation further validated that the first five osteoporosis SNPs are located in a super-enhancer region to regulate the expression of RANKL via long-range chromosomal interaction. Particularly, dual-luciferase assay showed that the region harboring rs9533090 in the super-enhancer has the strongest enhancer activity, and rs9533090 is an allele-specific regulatory SNP. Furthermore, deletion of the region harboring rs9533090 using CRISPR/Cas9 genome editing significantly reduced RANKL expression in both mRNA level and protein level. Finally, we found that the rs9533090-C robustly recruits transcription factor NFIC, which efficiently elevates the enhancer activity and increases the RANKL expression. In summary, we provided a feasible method to identify regulatory noncoding SNPs to distally regulate their target gene underlying the pathogenesis of osteoporosis by using bioinformatics data analyses and experimental validation. Our findings would be a potential and promising therapeutic target for precision medicine in osteoporosis. © 2018 American Society for Bone and Mineral Research.

Purification and characterization of a potential antifungal protein from Bacillus subtilis E1R-J against Valsa mali

In order to identify the antagonistic substances produced by Bacillus subtilis E1R-J as candidate of biocontrol agents for controlling Apple Valsa Canker, hydrochloric acid precipitation, reverse phase chromatography, gel filtration, and ion exchange chromatography were used. The purified fraction EP-2 showed a single band in native-polyacrylamide gel electrophoresis (native-PAGE) and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Fraction EP-2 was eluted from native-PAGE and showed a clear inhibition zone against V. mali 03-8. These results prove that EP-2 is one of the most important antifungal substances produced by B. subtilis E1R-J in fermentation broth. SDS-PAGE and Nano-LC-ESI-MS/MS analysis results demonstrated that EP-2 was likely an antifungal peptide (trA0A086WXP9), with a relative molecular mass of 12.44 kDa and isoelectric point of 9.94. The examination of antagonistic mechanism under SEM and TEM showed that EP-2 appeared to inhibit Valsa mali 03-8 by causing hyphal swelling, distortion, abnormality and protoplasts extravasation. Inhibition spectrum results showed that antifungal protein EP-2 had significantly inhibition on sixteen kinds of plant pathogenic fungi. The stability test results showed that protein EP-2 was stable with antifungal activity at temperatures as high as 100 °C for 30 min and in pH values ranging from 1.0 to 8.0, or incubated with each 5 mM Cu(2+), Zn(2+), Mg(2+), or K(+). However, the antifungal activity was negatively affected by Proteinase K treatment.

Purification, characterization, and heterologous expression of an antifungal protein from the endophytic Bacillus subtilis strain Em7 and its activity against Sclerotinia sclerotiorum

An antifungal protein exhibiting a high activity against Sclerotinia sclerotiorum in vivo was purified by ammonium sulfate precipitation, hydrophobic chromatography, and gel filtration chromatography from the culture filtrate of the endophytic Bacillus subtilis strain Em7. The protein was characterized as a β-1,3-1,4-glucanase according to amino acid analysis, and showed excellent properties in thermal stability and acid resistance. At the same time, the antifungal protein was cloned and heterologously expressed in Escherichia coli BL21. The recombinant protein was purified and showed similar enzymatic properties to the native protein, exhibiting strong inhibitory activity against S. sclerotiorum. This shows that the β-1,3-1,4-glucanase may play a very important role in B. subtilis Em7 biocontrol function. In addition, many physiochemical properties of the native and purified recombinant protein were compared, including the effect of pH, temperature, metal cations, substrate specificity, and kinetic parameters. All parameters were similar between the native and recombinant purified protein, indicating that the purified recombinant protein has potential for industrial applications.

Riga-Fede disease in a child

Riga-Fede disease (RFD) was initially described as a benign ulceration of the lingual frenum or tongue of infants, most commonly resulting from repetitive trauma by natal teeth. However, similar clinical manifestations can also be found in children with repetitive tongue-thrusting habits or certain neurological disorders. This report describes an unusual case of RFD in a 6-year-old Chinese boy. The lesion appeared as an ulcer on the anterior ventral surface of the child's tongue, and was caused by a repetitive tongue-thrusting habit. After eliminating the source of repetitive trauma and starting concurrent use of therapeutic drugs for 1 week, the lesion healed completely.

Cloning of flanking sequence in transgenic plants by restriction site-anchored single-primer polymerase chain reaction

Determining the insertion position of an exogenous gene in the target plant genome is one of the main issues in the transgenic plant field. This study introduced a simple, rapid, and accurate method to clone the flanking sequences of the transgenic bar gene as the anchoring gene in the transgenic maize genome using single-primer polymerase chain reaction (PCR). This method was based on the distribution of restriction sites in the maize genome and adopted the single-primer PCR method. Cloning the flanking sequences with the restriction site-anchored single-primer PCR simplified the experimental procedures by about 70% and reduced the experimental time by more than 80%. In conclusion, the restriction site-anchored single-primer PCR was a simple, rapid method to obtain the unknown flanking sequences in the transgenic plants.

Enzyme-antibody dual labeled gold nanoparticles probe for ultrasensitive detection of κ-casein in bovine milk samples

A dual labeled probe was synthesized by coating gold nanoparticles (AuNPs) with anti-κ-CN monoclonal antibody (McAb) and horseradish peroxidase (HRP) enzyme on their surface. The McAb was used as detector and HRP was used as label for signal amplification catalytically oxidize the substrate. AuNPs were used as bridges between the McAb and HRP. Based on the probe, an immunoassay was developed for ultrasensitive detection of κ-CN in bovine milk samples. The assay has a linear response range within 4.2-560 ng mL(-1). The limit of detection (LOD) was 4.2 ng mL(-1) which was 10 times lower than that of traditional McAb-HRP based ELISA. The recoveries of κ-CN from three brand bovine milk samples were from 95.8% to 111.0% that had a good correlation (R(2)=0.998) with those obtained by official standard Kjeldahl method. For higher sensitivity and as simple as the traditional ELISA, the developed immunoassay could provide an alternative approach for ultrasensitive detection of κ-CN in bovine milk sample.

Differential expression of 1-aminocyclopropane-1-carboxylate synthase genes during orchid flower senescence induced by the protein phosphatase inhibitor okadaic acid

Applying 10 pmol of okadaic acid (OA), a specific inhibitor of type 1 or type 2A serine/threonine protein phosphatases, to the orchid (Phalaenopsis species) stigma induced a dramatic increase in ethylene production and an accelerated senescence of the whole flower. Aminoethoxyvinylglycine or silver thiosulfate, inhibitors of ethylene biosynthesis or action, respectively, effectively inhibited the OA-induced ethylene production and retarded flower senescence, suggesting that the protein phosphatase inhibitor induced orchid flower senescence through an ethylene-mediated signaling pathway. OA treatment induced a differential expression pattern for the 1-aminocyclopropane-1-carboxylic acid synthase multigene family. Accumulation of Phal-ACS1 transcript in the stigma, labelum, and ovary induced by OA were higher than those induced by pollination as determined by "semiquantitative" reverse transcriptase-polymerase chain reaction. In contrast, the transcript levels of Phal-ACS2 and Phal-ACS3 induced by OA were much lower than those induced by pollination. Staurosporine, a protein kinase inhibitor, on the other hand, inhibited the OA-induced Phal-ACS1 expression in the stigma and delayed flower senescence. Our results suggest that a hyper-phosphorylation status of an unidentified protein(s) is involved in up-regulating the expression of Phal-ACS1 gene resulting in increased ethylene production and accelerated the senescence process of orchid flower.

Deoxyribonucleic acid profile and tumor progression in primary carcinoma in situ of the bladder: a study of 63 patients with grade 3 lesions

In 63 patients with primary grade 3 carcinoma in situ of the bladder flow cytometric deoxyribonucleic acid (DNA) analysis was performed at diagnosis and during an average followup of 63 months. The results of DNA measurements were related to disease progression, that is invasive tumor and/or metastatic disease. The DNA histograms were classified as diploid (2 patients) or aneuploid (61). A total of 3 categories of aneuploid tumors with different prognostic significance could be defined: 1) carcinoma in situ with 1 aneuploid cell population at diagnosis and with no change to multiple aneuploid cell populations throughout observation, 2) carcinoma in situ with 1 aneuploid cell population at diagnosis but with a later change to multiple aneuploid cell populations and 3) carcinoma in situ with multiple aneuploid cell populations already at diagnosis. At 5 years the progression-free survival for the 3 categories was 94%, 43% and 20%, respectively. Over-all, of the patients with multiple aneuploid cell populations (categories 2 and 3) 76% had progression, in contrast to 19% of those in category 1 (p less than 0.0005). In category 2 development of multiple aneuploid cell populations preceded progression in 8 of 11 progressive cases by an average of 20 months. Therefore, the occurrence of multiple aneuploid cell populations must be considered as a sign of high aggressiveness. We conclude that flow cytometric DNA analysis is a potent predictor of prognosis in cases of primary carcinoma in situ of the bladder.

[Prostatic carcinoid and neuroendocrine tumors--a case report]

This paper reports a rare primary prostatic adenocarcinoid tumor confirmed by electron microscopy as well as immunohistochemical method including prostate specific antigen and prostatic acid phosphatase. Electron microscopy showed the presence of neuroendocrine granules in the cytoplasm of some tumor cells and the latter method ruled out the possibility of secondary tumor from other organs. It is noted that prostatic adenocarcinoid tumor is one of the diffuse neuroendocrine system tumors. Although the histogenesis of these tumors is not entirely clear, it is believed to be of multiple origins, and may transform through metaplasia into neoplasm.

Studies of lymph nodes from patients with classical hemophilia

Within the last 18 months, we have noted the development of unexplained lymph node enlargement in otherwise asymptomatic patients with hemophilia. Because such changes are poorly understood and, in some patient groups, may be related to the acquired immunodeficiency syndrome (AIDS), we studied the enlarged lymph nodes in four patients with severe factor VIII deficiency and abnormally low peripheral blood helper-inducer/suppressor cell (OKT4/OKT8) ratios. Surgically excised lymph nodes were studied for histopathologic, electron microscopic, and chromosomal changes. Cell suspensions from these and normal nodes were also studied using monoclonal antibodies. Excised lymph nodes showed follicular hyperplasia. Electron microscopy revealed no viral particles or vesicular rosettes. Chromosomal aberrations included an acrocentric marker chromosome in one patient and monosomy 21 in another. T lymphocyte ratios (OKT4/OKT8) in lymph node suspensions were lower than those in nodes from normal controls (1.2 v 6.1) and reflected the lymphocyte ratio in peripheral blood. Mature B cell percentages were increased in the lymph nodes from patients with hemophilia (38% v 27% in controls). Patients treated with factor VIII concentrates and male homosexuals have similarities in persistent lymph node enlargement, histologic features of follicular hyperplasia, and changes in lymph node and circulating lymphocyte subpopulations.