A Novel Technique for the Management of Massive Hemoptysis: The Customized Endobronchial Silicone Blocker

OBJECTIVE

Massive hemoptysis (MH) has a high mortality rate. Therapeutic options include bronchoscopy for endobronchial lesions, bronchial artery embolization (BAE), and emergency surgery. Scant options exist for patients who are not candidates for these modalities. Culprit bronchial segment occlusion is an option to prevent "spillover flooding → hypoxia." Applying this concept, we describe a case series of MH control using a novel bronchoscopically inserted customized endobronchial silicone blocker (CESB). We analyzed the safety and efficacy of CESBs in a select subset of patients with MH.

METHODS

Inclusion criteria were patients with MH who were unstable for surgery/BAE, failed BAE, or relatively contraindicated/refused BAE. CESBs were manufactured on-site by modifying silicone stents, inserted using rigid bronchoscopy and reinforced with glue. The CESB was removed after 6 weeks when possible. A successful outcome was defined as immediate bleeding control with no recurrence after removal.

RESULTS

Over 4.5 years, 13 episodes of MH in 12 patients meeting the criteria specified earlier were treated with CESBs. Seven of 12 patients had tuberculosis, 4 active and 3 inactive. One patient had mucormycosis, 1 post-lobectomy, 1 endobronchial renal cell carcinoma, 1 fibrosing mediastinitis, and 1 patient had metastatic laryngeal Ca. Eight of 12 patients were taken for primary-CESB placement. Four of 12 patients were sent for BAE, which was unsuccessful, and rescue-CESB was done for definitive management. The success rate, as defined earlier, was 92.3%, with no deaths from MH.

CONCLUSIONS

Innovative bronchoscopically inserted CESBs are an effective strategy in MH when patients are unstable or fail conventional management.

DNA methylation and expression analyses reveal epialleles for the foliar disease resistance genes in peanut (Arachis hypogaea L.)

Objective

Low DNA sequence polymorphism despite enormous phenotypic variations in peanut indicates the possible role of epigenetic variations. An attempt was made to analyze genome-wide DNA methylation pattern and its influence on gene expression across 11 diverse genotypes of peanut.

Results

The genotypes were subjected to bisulfite sequencing after 21 days of sowing (DAS). CHG regions showed the highest (30,537,376) DNA methylation followed by CpG (30,356,066) and CHH (15,993,361) across 11 genotypes. The B sub-genome exhibited higher DNA methylation sites (46,294,063) than the A sub-genome (30,415,166). Overall, the DNA methylation was more frequent in inter-genic regions than in the genic regions. The genes showing altered methylation and expression between the parent (TMV 2) and its EMS-derived mutant (TMV 2-NLM) were identified. Foliar disease resistant genotypes showed significant differential DNA methylation at 766 sites corresponding to 25 genes. Of them, two genes (Arahy.1XYC2X on chromosome 01 and Arahy.00Z2SH on chromosome 17) coding for senescence-associated protein showed differential expression with resistant genotypes recording higher fragments per kilobase of transcript per million mapped reads (FPKM) at their epialleles. Overall, the study indicated the variation in the DNA methylation pattern among the diverse genotypes of peanut and its influence of gene expression.

Developing Transposable Element Marker System for Molecular Breeding

Transposable element (TE) marker system was developed considering the useful properties of the transposable elements such as their large number in the animal and plant genomes, high rate of insertion polymorphism, and ease of detection. Various methods have been employed for developing a large number of TE markers in several crop plants for genomics studies. Here we describe some of these methods including the recent whole genome search. We also review the application of TE markers in molecular breeding.

Mapping of important taxonomic and productivity traits using genic and non-genic transposable element markers in peanut (Arachis hypogaea L.)

A mapping population of recombinant inbred lines (RILs) derived from TMV 2 and its mutant, TMV 2-NLM was employed for mapping important taxonomic and productivity traits using genic and non-genic transposable element markers in peanut. Single nucleotide polymorphism and copy number variation using RAD-Sequencing data indicated very limited polymorphism between TMV 2 and TMV 2-NLM. But phenotypically they differed significantly for many taxonomic and productivity traits. Also, the RIL population showed significant variation for a few additional agronomic traits. A genetic linkage map of 1,205.66 cM was constructed using 91 genic and non-genic Arachis hypogaea transposable element (AhTE) markers. Using single marker analysis and QTL analysis, the markers with high phenotypic variance explained (PVE) were identified for branching pattern (32.3%), number of primary and secondary branches (19.9% and 28.4%, respectively), protein content (26.4%), days to 50% flowering (22.0%), content of oleic acid (15.1%), test weight (13.6%) and pod width (12.0%). Three genic markers (AhTE0357, AhTE0391, AhTE0025) with Arachis hypogaea miniature inverted-repeat transposable element (AhMITE1) activity in the genes Araip.TG1BL (B02 chromosome), Aradu.7N61X (A09 chromosome) and Aradu.7065G (A07 chromosome), respectively showed strong linkage with these taxonomic, productivity and quality traits. Since TMV 2 and TMV 2-NLM differed subtly at DNA level, the background noise in detecting the marker-trait associations was minimum; therefore, the markers identified in this study for the taxonomic and productivity traits may be significant and useful in peanut molecular breeding.