Efficacy of radioiodine therapy for treating 20 patients with pulmonary metastases from differentiated thyroid cancer and a meta-analysis of the current literature

Background

Radioiodine therapy (RAI) after total or near-total thyroidectomy is a recommended treatment for patients with pulmonary metastasis from differentiated thyroid cancer (DTC). However, the total effective rate of iodine-131 therapy remains controversial. This study aimed to determine the efficacy of RAI for treating patients with pulmonary metastasis from DTC, and to identify independent predictors of its efficacy.

Methods

We conducted a retrospective study to evaluate 20 patients with pulmonary metastasis from DTC who underwent RAI at our center at first and performed a meta-analysis to evaluate relevant literature regarding the overall efficacy of RAI and subgroup-specific efficacies subsequently.

Results

The efficacy rate at our center was 40%, and no significant differences were observed according to sex, age, pathological type, metastasis state, or interval between the initial RAI and final surgery. The meta-analysis revealed that the pooled overall efficacy rate was 58%, and significant differences were observed when we compared pulmonary metastasis versus pulmonary and other distant metastasis, age of < 40 years versus age of ≥ 40 years, papillary thyroid cancer versus follicular thyroid cancer and male patients versus female patients.

Conclusions

These results suggest that RAI is an effective treatment for patients with pulmonary metastasis from DTC after surgical treatment. The efficacy of RAI was significantly predicted by the presence of papillary thyroid cancer, age of < 40 years, the absence of non-lung distant metastasis and female patients.

Reevaluation of Two Quantitative Trait Loci for Type II Resistance to Fusarium Head Blight in Wheat Germplasm PI 672538

Fusarium head blight (FHB), mainly caused by Fusarium graminearum, is a destructive disease in wheat. A population consisting of 229 F₂ and F_2:3 plants derived from the cross PI 672538 × L661 was used to evaluate the reactions to FHB. The FHB resistance data distribution in the F₂ population indicates that some quantitative trait loci (QTLs) were controlling the FHB resistance in PI 672538. We further detected two major QTLs (Qfhs-2B, Qfhs-3B) from analysis of the resistance data and the PCR-amplified results using WinQTLCart 2.5 software. Qfhs-2B, flanked by Xbarc55-2B and Xbarc1155-2B, explained more than 11.6% of the phenotypic variation of the percentage of diseased spikelets (PDS), and Qfhs-3B, flanked by Xwmc54-3B and Xgwm566-3B, explained more than 10% of the PDS phenotypic variation in the F_2:3 population. In addition, Qfhs-3B was different from Fhb1 in terms of the pedigree, inheritance, resistance response, chromosomal location, and marker diagnosis. We also detected QTLs for other disease resistance indices, including the percentage of damaged kernels and 1,000-grain weight, in similar chromosomal regions. Therefore, the FHB resistance of PI 672538 was mainly controlled by two major QTLs, mapped on 2B (FhbL693a) and 3B (FhbL693b). PI 672538 could be a useful germplasm for improving wheat FHB resistance.

Identification and genetic mapping of the putative Thinopyrum intermedium-derived dominant powdery mildew resistance gene PmL962 on wheat chromosome arm 2BS

Powdery resistance putatively derived from Thinopyrum intermedium in the wheat line L962 is controlled by a single dominant gene designated PmL962 and mapped to chromosome arm 2BS. Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is a destructive disease affecting the production of wheat (Triticum aestivum). Powdery mildew resistance was putatively transferred from Thinopyrum intermedium to the common wheat line L962, which conferred resistance to multiple Chinese Bgt isolates. Genetic analysis of the powdery mildew response was conducted by crossing the resistant line L962 with the susceptible line L983. Disease assessments of the F1, F2, and F2:3 populations from the cross L983/L962 indicated that resistance was controlled by a single dominant gene. A total of 373 F2:3 lines and 781 pairs of genomic simple sequence repeat (SSR) primers were employed to determine the chromosomal location of the resistance gene. The gene was linked to four publicly available and recently developed wheat genomic SSR markers and seven EST-STS markers. The resistance gene was mapped to chromosome arm 2BS based on the locations of the linked markers. Pedigree, molecular marker and resistance response data indicated that the powdery mildew resistance gene in L962 is novel. It was temporarily designated PmL962. It is flanked by Xwmc314 and BE443737at genetic distances of 2.09 and 3.74 cM, respectively, and located in a 20.77 cM interval that is co-linear with a 269.4 kb genomic region on chromosome 5 in Brachypodium distachyon and a 223.5 kb genomic region on rice (Oryza sativa) chromosome 4. The markers that are closely linked to this gene have potential applications in marker-assisted breeding.

Genetic mapping of a putative Thinopyrum intermedium-derived stripe rust resistance gene on wheat chromosome 1B

Stripe rust resistance transferred from Thinopyrum intermedium into common wheat was controlled by a single dominant gene, which mapped to chromosome 1B near Yr26 and was designated YrL693. Stripe rust caused by Puccinia striiformis f. sp. tritici (Pst) is a highly destructive disease of wheat (Triticum aestivum). Stripe rust resistance was transferred from Thinopyrum intermedium to common wheat, and the resulting introgression line (L693) exhibited all-stage resistance to the widely virulent and predominant Chinese pathotypes CYR32 and CYR33 and to the new virulent pathotype V26. There was no cytological evidence that L693 had alien chromosomal segments from Th. intermedium. Genetic analysis of stripe rust resistance was performed by crossing L693 with the susceptible line L661. F(1), F(2), and F(2:3) populations from reciprocal crosses showed that resistance was controlled by a single dominant gene. A total 479 F(2:3) lines and 781 pairs of genomic simple sequence repeat (SSR) primers were employed to determine the chromosomal location of the resistance gene. The gene was linked to six publicly available and three recently developed wheat genomic SSR markers. The linked markers were localized to wheat chromosome 1B using Chinese Spring nulli-tetrasomic lines, and the resistance gene was localized to chromosome 1B based on SSR and wheat genomic information. A high-density genetic map was also produced. The pedigree, molecular marker data, and resistance response indicated that the stripe rust resistance gene in L693 is a novel gene, which was temporarily designated YrL693. The SSR markers that co-segregate with this gene (Xbarc187-1B, Xbarc187-1B-1, Xgwm18-1B, and Xgwm11-1B) have potential application in marker-assisted breeding of wheat, and YrL693 will be useful for broadening the genetic basis of stripe rust resistance in wheat.