Study of Nutrient Foramina of Dry Adult Human Clavicle.

As a modified long bone, the clavicle is most important bone for transmission of body weight from upper limb to the axial skeleton, for attachment of muscles and is a significant source of bone grafting. This descriptive cross-sectional study was conducted among 150 (65 right and 85 left) fully ossified dry human clavicle in Mymensingh Medical College, Mymensingh, Bangladesh from January 2020 to December 2020. Sample was collected by the help of nonrandom purposive sampling technique from Anatomy department of Mymensingh Medical College and Community Based Medical College, Bangladesh, Mymensingh. In this study, nutrient foramen was present in 86.67% (130) cases. On the right side, 87.69% (57) cases and on the left side, 85.88% (73) cases were found present. Out of 130 clavicles where nutrient foramen were present, 52.31% (68) nutrient foramina were on inferior surface, 46.92% (61) on posterior surface and 0.77% (1) on superior surface. On the right side, 49.12% (28) cases were found on inferior surface and 49.12% (28) were on posterior surface and remaining 1.75% (1) was on superior surface. On the left side, 54.79% (40) cases were found on inferior surface and 45.21% were on posterior surface whereas none was found on superior surface. Among the present 130 cases, 1 nutrient foramen was found in total 80% (104) cases and 2 in 20% (26) cases. In right side, the numbers of cases were 75.44% (43) for 1 and 24.56% (14) for 2 nutrient foramina. In left side, the number of cases of 1 was 83.56% (61) and 16.44% (12) for 2 foramina. The nutrient foraminal direction was 98.46% (128) towards acromial end and 1.54% (2) to sternal end. In the right side, the direction was 100% (57) towards acromial end. In the left side, the direction was 97.26% (71) towards acromial end and 2.74% (2) to sternal end. In the current study, the mean ±SD nutrient foramina of 65 clavicles of right side were 71.04±13.91 and 67.13±16.30 in 85 left sided clavicles. The purpose for undertaking this study was to obtain baseline data on nutrient foramen to help to predict the success rate and different surgical interventions regarding fractures and grafting.

Fine mapping of a grain weight quantitative trait locus, qGW6, using near isogenic lines derived from Oryza rufipogon IRGC105491 and Oryza sativa cultivar MR219.

Grain weight is a major component of rice grain yield and is controlled by quantitative trait loci. Previously, a rice grain weight quantitative trait locus (qGW6) was detected near marker RM587 on chromosome 6 in a backcross population (BC2F2) derived from a cross between Oryza rufipogon IRGC105491 and O. sativa cv. MR219. Using a BC2F5 population, qGW6 was validated and mapped to a region of 4.8 cM (1.2 Mb) in the interval between RM508 and RM588. Fine mapping using a series of BC4F3 near isogenic lines further narrowed the interval containing qGW6 to 88 kb between markers RM19268 and RM19271.1. According to the Duncan multiple range test, 8 BC4F4 near isogenic lines had significantly higher 100-grain weight (4.8 to 7.5% over MR219) than their recurrent parent, MR219 (P < 0.05). According to the rice genome automated annotation database, there are 20 predicted genes in the 88-kb target region, and 9 of them have known functions. Among the genes with known functions in the target region, in silico gene expression analysis showed that 9 were differentially expressed during the seed development stage(s) from gene expression series GSE6893; however, only 3 of them have known functions. These candidates provide targets for further characterization of qGW6, which will assist in understanding the genetic control of grain weight in rice.

Identification of quantitative trait loci for blast resistance in BC2F3 and BC2F5 advanced backcross families of rice.

Advanced backcross families derived from Oryza sativa cv MR219/O. rufipogon IRGC105491 were utilized for identification of quantitative trait loci (QTL) for blast resistance using simple sequence repeat markers. Two hundred and sixty-one BC(2)F(3) families were used to construct a linkage map, using 87 markers, which covered 2375.2 cM of 12 rice chromosomes, with a mean density of 27.3 cM. The families were evaluated in a greenhouse for resistance to blast disease caused by pathotypes P7.2 and P5.0 of Magnaporthe oryzae. Five QTLs (qBL5.1, qBL5.2, qBL6.1, qBL8.1, and qBL10.1) for pathotype P5.0 and four QTLs (qBL5.3, qBL5.4, qBL7.1, and qBL8.2) for pathotype P7.2 were identified using the BC(2)F(3) families. Another linkage map was also constructed based on 31 BC(2)F(5) families, using 63 SSR markers, which covered 474.9 cM of 9 rice chromosomes, with a mean density of 8.01 cM. Five suggestive QTLs (qBL11.2, qBL11.3, qBL12.1, qBL12.2, qBL12.3) and one putative QTL (qBL2.1) were identified for pathotype P7.2. Also, seven suggestive QTLs (qBL1.1, qBL2.2, qBL4.1, qBL4.2, qBL5.3, qBL8.3, and qBL11.1) were detected for pathotype P5.0. We conclude that there is a non-race-specific resistance spectrum of O. rufipogon against M. oryzae pathotypes.