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Quantitative trait loci (QTL) examination on the joinmap for agronomic and fiber quality traits revealed highly recombined and gene abundant regions on cotton chromosomes. The compilation of genetic linkage maps and joint maps from different breeding gene pools enabled partial dissection of the A and D subgenomes in G. hirsutum.

Properly terminating furrow irrigation in mid-southern United States (U.S.) crops could reduce irrigation costs, the likelihood of adverse harvest conditions, and agricultural withdrawal from the Mississippi River Valley Alluvial Aquifer (MRVAA). This research was conducted to determine an optimum termination window for furrow-irrigated cotton (Gossypium hirsutum L.) in the mid-southern U.S. The effects of irrigation termination timing on cotton lint yield, net returns, and irrigation water use efficiency (IWUE) were evaluated on a Leeper silty clay loam (fine, smectitic, nonacid, thermic Vertic Epiaquepts) and on a Dundee silty clay (fine-silty, mixed, active, Typic Endoaqualfs). Neither terminating nor continuing to irrigate cotton from cutout (NAWF = 5) up to three weeks past first cracked boll had an effect on lint yield or fiber quality (p ≥ 0.6107). Irrigation water use efficiency declined when water was applied past cutout (p < 0.0001). Results indicate that irrigation in cotton can be terminated at cutout without adversely effecting lint yield and fiber quality if soil water potential does not exceed -130 kPa prior to first cracked boll. Terminating irrigation in cotton at cutout could reduce late season irrigation cost and reduce water withdrawal from the MRVAA thus improving it sustainability. [ABSTRACT FROM AUTHOR]

PurposeTo determine the predictive value of early Phase trials (I–II) for the ocular hypotensive efficacy observed in Phases III and IV.DesignA review of published literature.MethodsThis study evaluated 12 medicines in 65 articles in the literature with at least two phases available.ResultsFor medicines with Phase I results available (n=3), the average reduction in intraocular pressure (IOP) from untreated baseline was 16%, 26% for Phase II, 26% for Phase III, and 24% for Phase IV. For medicines with Phase II results available (n=6), the average reduction in IOP was 23%, 24% for Phase III, and 23% for Phase IV. For medicines with Phase III results available (n=11), the average reduction in IOP was 25% and 24% for Phase IV.ConclusionThis study indicates that early phase trials usually approximated the results of later regulatory studies and post-commercialization trials.Eye (2008) 22, 985–988; doi:10.1038/sj.eye.6702913; published online 22 June 2007 [ABSTRACT FROM AUTHOR]

Purpose: To compare the efficacy and safety of brimonidine 0.2% vs unoprostone 0.15%, both added to timolol maleate 0.5% each given twice daily.Methods: In this prospective, multi-centred, double-masked, crossover comparison, patients were randomized to one treatment group for a 6-week treatment period, and then crossed over to the opposite treatment. Measurements were performed at 0800, 1000, 1600, 1800, and 2000 h at baseline and at the end of each treatment period.Results: In all, 33 patients entered this trial and 29 completed. The baseline trough intraocular pressure (IOP) was 23.3+/-2.4 and the diurnal curve IOP was 22.0+/-1.3 mmHg. For the brimonidine and timolol maleate treatment group, the trough IOP was 21.6+/-3.3 and the diurnal curve IOP was 19.8+/-2.1 mmHg, while the timolol and unoprostone treatment showed a trough IOP of 20.9+/-3.8 and a diurnal curve IOP of 19.3+/-2.4 mmHg. There was no significant difference between treatment groups at any time point for the diurnal curve, or in the reduction from baseline (P>0.05). Both treatments failed to statistically reduce the IOP from baseline at 1800 h. There was no difference between treatment groups regarding ocular and systemic unsolicited adverse events, but patients admitted to more dryness (P=0.02) and burning upon instillation (P<0.0001) with unoprostone by survey.Conclusion: Brimonidine 0.2% or unoprostone 0.15% added to timolol maleate 0.5% provide similar efficacy and safety throughout the daytime diurnal curve. [ABSTRACT FROM AUTHOR]

Recent advances in genomic technologies have generated a large number of expressed sequence tags (ESTs) in cotton. Many of these ESTs are available in public databases, which offer an opportunity to identify simple sequence repeats (SSR) in ESTs by data mining. These sequences may provide an estimate of diversity in the expressed portion of the genome and may be useful for comparative mapping, for tagging important traits of interest, and for additional map-based cloning of important genes. One hundred and thirty-three SSR-containing ESTs (EST-SSRs) were identified by analyzing 9,948 sequences belonging to Gossypium hirsutum L. in GenBank. The EST-SSR sequences and the related EST sequences without SSRs were clustered to reduce redundancy and to develop consensus sequences. Primers were designed for 84 of these EST-SSRs and were tested for their ability to amplify and detect diversity among three lines of G. hirsutum and one line of G. barbadense L. An average of three amplicons was obtained per primer pair. The intraspecies polymorphism rate among the G. hirsutum cotton cultivars was 26 % and interspecific polymorphism between G. hirsutum and G. barbadense was 52%. The presence of SSRs in the EST-SSR markers was confirmed by cloning and sequencing of the amplified products of randomly selected primer pairs from four different lines. To explore the potential use of the EST-SSR loci for comparative mapping, these sequences were compared against different plant species using BLAST assuming an e-value of 1E-10 or less as a significant sequence similarity. About 74% of the EST-SSRs were from fiber-related tissues in G. hirsutum, whereas 26 % were from other tissues, such as cotton bolls and cottonseed. Fifty-five percent of these EST-SSR sequences matched sequences in G. arboretum L., and 19% of the sequences showed considerable sequence similarity with sequences in the Arabidopsis thaliana (L.) Heynh. genome. In this manuscript, information about the primer sequence, repeat motif, and the degree of polymorphism of cotton EST-SSR markers is reported. A cost-effective strategy to develop EST-SSR markers by exploiting EST databases is demonstrated for the first time in cotton. [ABSTRACT FROM AUTHOR]

Purpose To compare ocular tolerability of dorzolamide 2%, brinzolamide 1%, and placebo given three times daily. Methods A prospective, double-masked, three-centre, crossover comparison in which 25 ocular hypertensive or primary-open angle glaucoma subjects were randomized to receive dorzolamide, brinzolamide, or placebo three times daily for 3 days. Intraocular pressure, visual acuity, a visual analogue scale, and ocular and systemic symptom queries were completed at the end of each period. Results After chronic dosing, there was a significant difference in ocular pain on the visual analogue scale among the groups at the 10-s postinstillation time point with dorzolamide having the highest level (22.5±28.9) compared to brinzolamide (5.0±8.7) or placebo (3.2±10.4) (P = 0.0006). No differences between groups were observed preinstillation nor following dosing at 3 or 10-min postinstillation. On the initial instillation, the 10-s postinstillation pain was rated as 43.3±77.1, which was significantly higher than after chronic dosing (P = 0.017). On the ocular symptom query, dorzolamide had the highest incidence of burning/stinging and redness compared to the other groups, but was generally characterized as mild. There were no significant differences in the visual acuity at any time point. Conclusions This study suggests that subjects treated with dorzolamide suffer more ocular pain upon instillation compared to brinzolamide or placebo. However, pain symptoms are fewer following chronic dosing and are generally characterized as mild. [ABSTRACT FROM AUTHOR]

Recent advances in genomic technologies have generated a large number of expressed sequence tags (ESTs) in cotton. Many of these ESTs are available in public databases, which offer an opportunity to identify simple sequence repeats (SSR) in ESTs by data mining. These sequences may provide an estimate of diversity in the expressed portion of the genome and may be useful for comparative mapping, for tagging important traits of interest, and for additional map-based cloning of important genes. One hundred and thirty-three SSR-containing ESTs (EST-SSRs) were identified by analyzing 9,948 sequences belonging to Gossypium hirsutum L. in GenBank. The EST-SSR sequences and the related EST sequences without SSRs were clustered to reduce redundancy and to develop consensus sequences. Primers were designed for 84 of these EST-SSRs and were tested for their ability to amplify and detect diversity among three lines of G. hirsutum and one line of G. barbadense L. An average of three amplicons was obtained per primer pair. The intraspecies polymorphism rate among the G. hirsutum cotton cultivars was 26% and interspecific polymorphism between G. hirsutum and G. barbadense was 52%. The presence of SSRs in the EST-SSR markers was confirmed by cloning and sequencing of the amplified products of randomly selected primer pairs from four different lines. To explore the potential use of the EST-SSR loci for comparative mapping, these sequences were compared against different plant species using BLAST assuming an e-value of 1E-10 or less as a significant sequence similarity. About 74% of the EST-SSRs were from fiber-related tissues in G. hirsutum, whereas 26% were from other tissues, such as cotton bolls and cottonseed. Fifty-five percent of these EST-SSR sequences matched sequences in G. arboretum L., and 19% of the sequences showed considerable sequence similarity with sequences in the Arabidopsis thaliana (L.) Heynh. genome. In this manuscript, information about the primer sequence, repeat motif, and the degree of polymorphism of cotton EST-SSR markers is reported. A cost-effective strategy to develop EST-SSR markers by exploiting EST databases is demonstrated for the first time in cotton. [ABSTRACT FROM AUTHOR]

The narrow genetic base of cultivated cotton germplasm is hindering the cotton productivity worldwide. Although potential genetic diversity exists in Gossypium genus, it is largely 'underutilized' due to photoperiodism and the lack of innovative tools to overcome such challenges. The application of linkage disequilibrium (LD)-based association mapping is an alternative powerful molecular tool to dissect and exploit the natural genetic diversity conserved within cotton germplasm collections, greatly accelerating still 'lagging' cotton marker-assisted selection (MAS) programs. However, the extent of genome-wide linkage disequilibrium (LD) has not been determined in cotton. We report the extent of genome-wide LD and association mapping of fiber quality traits by using a 95 core set of microsatellite markers in a total of 285 exotic Gossypium hirsutum accessions, comprising of 208 landrace stocks and 77 photoperiodic variety accessions. We demonstrated the existence of useful genetic diversity within exotic cotton germplasm. In this germplasm set, 11-12% of SSR loci pairs revealed a significant LD. At the significance threshold (r(2)>/=0.1), a genome-wide average of LD declines within the genetic distance at <10 cM in the landrace stocks germplasm and >30 cM in variety germplasm. Genome wide LD at r(2)>/=0.2 was reduced on average to approximately 1-2 cM in the landrace stock germplasm and 6-8 cM in variety germplasm, providing evidence of the potential for association mapping of agronomically important traits in cotton. We observed significant population structure and relatedness in assayed germplasm. Consequently, the application of the mixed liner model (MLM), considering both kinship (K) and population structure (Q) detected between 6% and 13% of SSR markers associated with the main fiber quality traits in cotton. Our results highlight for the first time the feasibility and potential of association mapping, with consideration of the population structure and stratification existing in cotton germplasm resources. The number of SSR markers associated with fiber quality traits in diverse cotton germplasm, which broadly covered many historical meiotic events, should be useful to effectively exploit potentially new genetic variation by using MAS programs.

Ligon lintless (Li(1)) is a monogenic, dominant mutant in cotton, whose expression results in extreme reductions in fiber length on mature seed. The objectives of this research were to compare fiber initiation between the Li(1) mutant and TM-1 to reveal the fiber initiation differences between normal and mutant phenotypes, to develop a linkage map of simple sequence repeat (SSR) markers with the Li(1) locus, and to identify the chromosomal location of the Li(1) locus. Comparative scanning electron microscopy studies of fiber development in a normal TM-1 genotype and the near-isogenic Li(1) mutant at 1 and 3 days postanthesis revealed little differences between the two during early stages of development, suggesting that Li(1) gene expression occurs later, probably during the elongation phase. Thirty-eight SSR loci were found to be polymorphic between TM-1 and Li(1) and were used for mapping in an F(2) population. Twenty-two SSR loci, along with Li(1), were located on eight linkage groups, covering a total genetic distance of 218.3 cM. Analysis of individual monosomic and monotelodisomic plants indicated that two SSR loci (MP4030 and MP673) from the Li(1) linkage group were located on chromosome 22.