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With global warming and regional decreases in precipitation, drought has become a problem worldwide. As the number of arid regions in the world is increasing, drought has become a major factor leading to significant crop yield reductions and food crises. Soybean is a crop that is relatively sensitive to drought. It is also a crop that requires more water during growth and development. The aim of this study was to identify the quantitative trait locus (QTL) that affects drought tolerance in soybean by using a recombinant inbred line (RIL) population from a cross between the drought-tolerant cultivar 'Jindou21' and the drought-sensitive cultivar 'Zhongdou33'. Nine agronomic and physiological traits were identified under drought and well-watered conditions. Genetic maps were constructed with 923,420 polymorphic single nucleotide polymorphism (SNP) markers distributed on 20 chromosomes at an average genetic distance of 0.57 centimorgan (cM) between markers. A total of five QTLs with a logarithm of odds (LOD) value of 4.035–8.681 were identified on five chromosomes. Under well-watered conditions and drought-stress conditions, one QTL related to the main stem node number was located on chromosome 16, accounting for 17.177% of the phenotypic variation. Nine candidate genes for drought resistance were screened from this QTL, namely Glyma.16G036700, Glyma.16G036400, Glyma.16G036600, Glyma.16G036800, Glyma.13G312700, Glyma.13G312800, Glyma.16G042900, Glyma.16G043200, and Glyma.15G100700. These genes were annotated as NAC transport factor, GATA transport factor, and BTB/POZ-MATH proteins. This result can be used for molecular marker-assisted selection and provide a reference for breeding for drought tolerance in soybean. [ABSTRACT FROM AUTHOR]

Background With widespread use of diagnostic imaging modalities, incidental thyroid nodules are frequently identified in patients for unrelated reasons. If underlying thyroid cancer risk in such patients is significant, further evaluation becomes imperative. This study evaluates the malignancy rate of incidentally discovered compared to clinically apparent thyroid nodules in surgical patients. Methods A retrospective review of prospectively collected data of 809 patients who underwent thyroidectomy at a tertiary referral center was performed. The association between incidental discovery of thyroid nodules, malignancy rates, and clinicopathologic characteristics was assessed. Results Of 809 patients, 12% ( n = 98) had incidental thyroid nodules, where malignancy was found in 65 (66%) of these patients. The overall rate of malignancy identified incidentally by routine imaging was 14% (65/466). Most common imaging modalities leading to detection were ultrasound (32%), computed tomography (29%), and magnetic resonance imaging (23%). Of patients with incidental thyroid nodules harboring malignancy, follicular variant papillary thyroid cancer (PTC) (48%), classical variant PTC (18%), tall cell variant PTC (12%), and diffuse sclerosing variant PTC (12%) were most commonly found. Patients with malignant incidental thyroid nodules had more lymphovascular invasion and positive lymph nodes compared to nonincidental malignant thyroid nodules (53% versus 41% and 47% versus 33%, P < 0.05, respectively). Conclusions Incidentally discovered thyroid nodules by imaging represent an important group of surgical patients with clinically significant rates of underlying malignancy. Patients with incidentally discovered thyroid nodules by imaging should undergo appropriate evaluation and counseling for further surgical treatment. [ABSTRACT FROM AUTHOR]

The LOR (LURP-one related) family genes encode proteins containing a conserved LOR domain. Several members of the LOR family genes are required for defense against Hyaloperonospora parasitica (Hpa) in Arabidopsis. However, there are few reports of LOR genes in response to abiotic stresses in plants. In this study, a genome-wide survey and expression levels in response to abiotic stresses of 36 LOR genes from Glycine max were conducted. The results indicated that the GmLOR gene family was divided into eight subgroups, distributed on 14 chromosomes. A majority of members contained three extremely conservative motifs. There were four pairs of tandem duplicated GmLORs and nineteen pairs of segmental duplicated genes identified, which led to the expansion of the number of GmLOR genes. The expansion patterns of the GmLOR family were mainly segmental duplication. A heatmap of soybean LOR family genes showed that 36 GmLOR genes exhibited various expression patterns in different tissues. The cis-acting elements in promoter regions of GmLORs include abiotic stress-responsive elements, such as dehydration-responsive elements and drought-inducible elements. Real-time quantitative PCR was used to detect the expression level of GmLOR genes, and most of them were expressed in the leaf or root except that GmLOR6 was induced by osmotic and salt stresses. Moreover, GmLOR4/10/14/19 were significantly upregulated after PEG and salt treatments, indicating important roles in the improvement of plant tolerance to abiotic stress. Overall, our study provides a foundation for future investigations of GmLOR gene functions in soybean. [ABSTRACT FROM AUTHOR]