Polymorphism of keratin 1 associates with systemic lupus erythematosus and systemic sclerosis in a south Chinese population.

Both systemic lupus erythematosus (SLE) and systemic sclerosis (SSc) diseases are related to the genetic and environmental factors, causing damage to the skin. The mutations of keratin 1 gene (KRT1) were reported to associate with skin diseases. The single-nucleotide polymorphism (SNP, rs14024) and the indel polymorphism (cds-indel, rs267607656), consisting mostly of the common haplotypes and could be used for genotyping of KRT1. We used the PCR with sequence specific primers (PCR-SSP) to determine the genotype of KRT1 in 164 SLE, 99 SSc patients, and 418 healthy controls. The results showed that the mutant with G at SNP rs14024 was associated with the high risk to SLE (p = 6.48×10-5) and SSc (p = 8.75×10-5), while the deletion allele at rs267607656 was associated with the low risk to SSc (p = 4.89×10-4) comparing to the normal controls. Haplogenotype, Del-/MU+ was associated with high susceptibility to SLE (OR = 1.87, p = 0.001) and SSc (OR = 2.29, p = 2.34×10-4). In contrast, the Haplogenotype Del+/MU- was associated with resistance to SLE (OR = 0.35, p = 6.24×10-5) and SSc (OR = 0.34, p = 0.001). This study demonstrates that the variations in KRT1 and the specific polymorphism of KRT1 in this Chinese Han population are associated with autoimmune diseases SLE and SSc. Typing KRT1 might be helpful to identify SLE and SSc patients

Longitudinal Profiling of Plasma Cytokines and Its Association With Postoperative Delirium in Elderly Patients Undergoing Major Lower Limb Surgery: A Prospective Observational Study

BackgroundSurgery is accompanied by a systemic inflammatory response that may presage delirium in susceptible individuals. Little is known about the trajectory of plasma proinflammatory cytokines and their potential associations with postoperative delirium (POD). The current study longitudinally assessed both pro and anti-inflammatory plasma cytokine response and development of POD in older surgical patients to investigate associations with individual and/or clusters of cytokines that may indicate pathogenic mechanisms.MethodsA prospective longitudinal study sought to enroll patients >60 years old who were scheduled for major lower limb surgery under general anesthesia. Blood was obtained preoperatively and postoperatively from day 1 through postoperative day 4 for measurement of plasma interleukin-1β (IL-1β), IL-2, IL-4, IL-6, soluble IL-6 receptor (sIL-6R), IL-10, and tumor necrosis factor-α (TNF-α). Participants were assessed for POD twice daily for 4 days using the confusion assessment method. Trajectory of postoperative changes in plasma cytokines was determined by a group-based trajectory modeling analysis that was informed by distinct cytokines identified by time-dependent Cox regression model.ResultsOne hundred eighty-eight patients were assessed for eligibility of whom 129 underwent major surgery and 126 had complete datasets for final analysis. POD was diagnosed in 31 of 126 patients (24.6%). Time-dependent Cox regression model identified that higher IL-6 and sIL-6R levels were associated with higher risk of developing POD. A two-cluster model (stable lower and fluctuating higher levels) was considered to be the most statistically appropriate model for IL-6 and sIL-6R trajectory. More participants with fluctuating higher IL-6 were delirious (73.3% vs 18.0%, P = .001) as were those with fluctuating higher sIL-6R (81.3% vs 16.4%, P = .001).ConclusionsAs higher IL-6 and sIL-6R levels were significantly associated with higher risk of POD and the combination is required for IL-6 trans-signaling, it is possible that activation of this pathway may be associated with POD. Furthermore, it will be important to determine whether high levels of the combination of IL-6 and sIL-6R can be an early biomarker for the subsequent development of POD

The frequencies of haplotype of KRT1 gene in SLE, SSc and control group.

<p>The frequencies of haplotype of KRT1 gene in SLE, SSc and control group.</p

The genotyping results of samples by PCR-SSP.

<p>(a): Typing for SNP rs14024 is based on the two PCR reactions using specific sequence primers, SNP with A or G, or both were designed with a size band of 410 bp in PCR; a 689 bp band serves as the internal positive control. (b): The 21bp nucleotide deletion was detected with a small band (S) and wild type of rs267607656 is demonstrated with a large band (L) in PRC products. The PCR results of three control samples (con1, con2 and con3) and object samples (S1, S2, S3 et al.) are given, following by the read of typing results in parenthesis.</p

The genotype frequencies of SNP rs14024 and indel rs267607656 in different populations.

<p>The genotype frequencies of SNP rs14024 and indel rs267607656 in different populations.</p

Validation of PCR-SSP genotyping assay.

<p>6 reference DNA samples identified with Sanger sequence-based typing (SBT) are utilized to validate the new method of PCR-SSP typing. (a): PCR products with KRT1 exon 9 DNA sequences were sequenced with forward and reverse sequencing primers. The 21-bp deletion and non-deletion in 6 samples are labeled in the left profiles of reverse-primer sequencing. The SNPs rs14024 with A, G or both (A/G) at position 388 in exon 9 of KRT1 gene are given in the right side. The same samples were used to type by PCR-SSP. (b): A 689 bp band, amplified by GAPDH primers serves as a positive control. Typing of SNP with either A, G or both at rs 14024 is read based on the presence of a 410-bp band in PCR products in different primer pairs. (c): The indel polymorphism in rs267607656 of KRT1 is detected by the sizes of PCR gels with larger bands (L, no deletion) and/or small bands (S, with deletion). The relatively small size (S) detected is stand for the existing of a 21-bp deletion in KRT1 gene.</p