Associations of Genes for Killer Cell Immunoglobulin-Like Receptors and Their Human Leukocyte Antigen-A/B/C Ligands with Abdominal Aortic Aneurysm

Abdominal aortic aneurysm (AAA) is an immune-mediated disease with a genetic component. The multifactorial pathophysiology is not clear and there is still no pharmacotherapy to slow the growth of aneurysms. The signal integration of cell-surface KIRs (killer cell immunoglobulin-like receptors) with HLA (ligands, human leukocyte class I antigen molecules) modulates the activity of natural killer immune cells. The genetic diversity of the KIR/HLA system is associated with the risk of immune disorders. This study was a multivariate analysis of the association between genetic variants of KIRs, HLA ligands, clinical data and AAA formation. Genotyping was performed by single polymerase chain reaction with sequence-specific primers using commercial assays. Patients with HLA-A-Bw4 have a larger aneurysm by an average of 4 mm (p = 0.008). We observed a relationship between aneurysm diameter and BMI in patients with AAA and co-existing CAD; its shape was determined by the presence of HLA-A-Bw4. There was also a nearly 10% difference in KIR3DL1 allele frequency between the study and control groups. High expression of the cell surface receptor KIR3DL1 may protect, to some extent, against AAA. The presence of HLA-A-Bw4 may affect the rate of aneurysm growth and represents a potential regional pathogenetic risk of autoimmune injury to the aneurysmal aorta.

Development and Validation of a Forensic Multiplex System With 38 X-InDel Loci

In the present study, a novel multiplex system, AGCU X-InDel 38 kit, was designed to amplify 38 X-InDel markers and amelogenin in a single Polymerase Chain Reaction (PCR). To demonstrate the suitability and efficiency for forensic applications, a series of validation experiments were conducted, including sensitivity, species specificity, reproducibility, stability, case samples, balance of peak height, size precision, as well as allele frequency and forensic parameter analysis. The results showed that AGCU X-InDel 38 kit was capable to get full profiles even with 62.5 pg of template DNA, and full profiles can be obtained when hematin concentration ≤25 μmol/L, or hemoglobin concentration ≤50 μmol/L, showing good tolerance to six common inhibitors. Moreover, the analyzed case samples indicated that AGCU X-InDel 38 kit had better performance for degraded and trace DNA samples. The 200 unrelated males from Guangdong Han population showed that the combined PDMale and PDFemale were both more than 0.999999999, and the combined MECKrüger, MECKishida, and MECDesmarais Duo were 0.999369481, 0.999999917, and 0.999941556, respectively. Robust discrimination capability of this novel multiplex system could be demonstrated through the high values of forensic parameters. In conclusion, AGCU X-InDel 38 kit is sensitive, precise, reproducible, and highly informative and could be used as a complementary tool for complex and challenging kinship cases.

Role of Respiratory Syncytial Virus in Pediatric Pneumonia

Respiratory viral infections represent the leading cause of hospitalization in infants and young children worldwide and the second leading cause of infant mortality. Among these, Respiratory Syncytial Virus (RSV) represents the main cause of lower respiratory tract infections (LRTIs) in young children worldwide. RSV manifestation can range widely from mild upper respiratory infections to severe respiratory infections, mainly bronchiolitis and pneumonia, leading to hospitalization, serious complications (such as respiratory failure), and relevant sequalae in childhood and adulthood (wheezing, asthma, and hyperreactive airways). There are no specific clinical signs or symptoms that can distinguish RSV infection from other respiratory pathogens. New multiplex platforms offer the possibility to simultaneously identify different pathogens, including RSV, with an accuracy similar to that of single polymerase chain reaction (PCR) in the majority of cases. At present, the treatment of RSV infection relies on supportive therapy, mainly consisting of oxygen and hydration. Palivizumab is the only prophylactic method available for RSV infection. Advances in technology and scientific knowledge have led to the creation of different kinds of vaccines and drugs to treat RSV infection. Despite the good level of these studies, there are currently few registered strategies to prevent or treat RSV due to difficulties related to the unpredictable nature of the disease and to the specific target population.

Single-tube genotyping for small insertion/deletion mutations: simultaneous identification of wild type, mutant and heterozygous alleles

Current methods of genotyping small insertion/deletion (indel) mutations are costly, laborious, and can be unreliable. To address this, we have developed a method for small indel genotyping in a single polymerase chain reaction, with wild-type, heterozygous and mutant alleles distinguishable by band pattern in routine agarose gel electrophoresis. We demonstrate this method with multiple genes to distinguish 10 bp, 4 bp and even 1 bp deletions from the wild type. Through systematic testing of numerous primer designs, we also propose guidelines for genotyping small indel mutations. Our method provides a convenient approach to genotyping small indels derived from clustered regularly interspaced short palindromic repeats-mediated gene editing, N-ethyl-N-nitrosourea induced mutagenesis or diagnosis of naturally occurring polymorphisms/mutations.

Associations of ACE I/D polymorphism with the levels of ACE, kallikrein, angiotensin II and interleukin-6 in STEMI patients

This study aimed to compare the plasma levels of angiotensin-I converting enzyme (ACE), Angiotensin II (AngII), kallikrein (KLK1) and interleukin-6 (IL-6) in ST segment elevation myocardial infarction (STEMI) patients with different ACE Insertion/deletion (I/D) polymorphisms in a Chinese population. The ACE genotypes were determined in the 199 STEMI patients and 216 control subjects. STEMI patients were divided into three groups based on the ACE genotypes. Single polymerase chain reaction (PCR) was performed to characterize ACE I/D polymorphisms. Plasma levels of ACE, AngII, KLK1 and IL-6 were measured by enzyme-linked immunosorbent assay (ELISA). We found that the DD or ID genotype was significantly independently associated with high ACE (OR = 4.697; 95% CI = 1.927–11.339), KLK1 (3.339; 1.383–8.063) and IL-6 levels (OR = 2.10; 1.025–4.327) in STEMI patients. However, there was no statistical significance between the ACE I/D polymorphism and AngII plasma levels whether in univariate or multivariate logistic regression. Additionally, we detected a significantly positive correlation between plasma KLK1 levels and IL-6 levels in STEMI patients (r = 0.584, P < 0.001). The study showed high levels of ACE, KLK1 and IL-6 were detected when the D allele was present, but AngII plasma levels was not influenced by the ACE I/D polymorphism.

Population Structures of ‘Candidatus Liberibacter asiaticus’ in Southern China

Huanglongbing (HLB) is a highly detrimental citrus disease associated with ‘Candidatus Liberibacter asiaticus’, a nonculturable alpha-proteobacterium. Characterization of the bacterial populations is important for development of disease management strategies. In this study, the ‘Ca. L. asiaticus’ populations in eight provinces in southern China where HLB is endemic were analyzed based on tandem repeat number (TRN) variations in a previously characterized genomic locus CLIBASIA_01645. Of the 224 HLB samples collected, 175 (78.3%) samples yielded single polymerase chain reaction (PCR) amplicons (the single amplicon group, SAG) and 49 (21.7%) samples produced multiple PCR amplicons (the multiple amplicon group, MAG). Variations in SAG are summarized by Nei's diversity index (H) and ratio of TRN ≤ 10/TRN > 10 genotypes (R10). Variations in the MAG are described by the percentage of occurrence (PMAG). At an orchard-level comparison, the ‘Ca. L. asiaticus’ population from a Guangdong orchard (n = 24) showed H = 0.50, R10 = 23, and PMAG = 0, significantly different from that of the non-Guangdong orchards in Yunnan (n = 23), H = 0.83, R10 = 2.3, and PMAG = 11.5, and in Hainan (n = 35), H = 0.88, R10 = 1.5, and PMAG = 16.7. In a region-level consideration, the Guangdong ‘Ca. L. asiaticus’ population (n = 78) was H = 0.77, R10 = 25, and PMAG = 1.3, whereas the non-Guangdong population (n = 84) was H = 0.91, R10 = 1.6, and PMAG = 26.9. Overall, significant differences were observed between the ‘Ca. L. asiaticus’ population from Guangdong Province and those from the other provinces. A strong aggregation of TRN = 6, 7, and 8 genotypes is characteristic to the ‘Ca. L. asiaticus’ population in Guangdong. Referenced to genome annotation, we propose that rearrangement of tandem repeats at locus CLIBASIA_01645 could be associated with bacterial environmental adaptation.

Diffuse large B-cell lymphomas with CDKN2A deletion have a distinct gene expression signature and a poor prognosis under R-CHOP treatment: a GELA study

Genomic alterations play a crucial role in the development and progression of diffuse large B-cell lymphomas (DLBCLs). We determined gene copy number alterations (GCNAs) of TP53, CDKN2A, CDKN1B, BCL2, MYC, REL, and RB1 with a single polymerase chain reaction (PCR) assay (quantitative multiplex PCR of short fragments [QMPSF]) in a cohort of 114 patients with DLBCL to assess their prognostic value and relationship with the gene expression profile. Losses of TP53 and CDKN2A, observed in 8% and 35% of patients, respectively, were significantly associated with a shorter survival after rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) treatment, independently of the International Prognostic Index and of the cell of origin. Analysis of the 9p21 genomic region indicated that transcripts encoding p14ARF and p16INK4A were both disrupted in most patients with CDKN2A deletion. These patients predominantly had an activated B-cell profile and showed a specific gene expression signature, characterized by dysregulation of the RB/E2F pathway, activation of cellular metabolism, and decreased immune and inflammatory responses. These features may constitute the molecular basis sustaining the unfavorable outcome and chemoresistance of this DLBCL subgroup. Detection of TP53 and CDKN2A loss by QMPSF is a powerful tool that could be used for patient stratification in future clinical trials.