Meiotic mutants in potato: valuable variants.

Potato biology; Description and genetic charecteristics of meiotic mutants in potatoes; Mutants affecting microsporogenesis; Mutations affecting megasporogenesis; Use of meiotic mutants in potato breeding; Germplasm transfer with meiotic mutants; Use of meiotic mutants in genetics; Application of meiotic mutants in cytology; Meiotic mutants and evolution of Solanum species; Future directions

Peritoneal Dialysis Fluid Concentrations of Linezolid in the Treatment of Vancomycin‐Resistant Enterococcus faecium Peritonitis

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90108/1/phco.23.12.1322.32702.pd

Evaluation under long-day conditions of 4x-2x progenies from crosses between potato cultivars and haploid Tuberosum-solanum chacoense hybrids.

Twelve 4x families (obtained from a sub-set of crosses between seven 4x-potato cultivars and three 2x haploid Tuberosum-Solanum chacoense hybrids) were evaluated at Hancock, Wisconsin (USA). The 4x-parents were elite cultivars selected for adaptation in three continents (Europe, South America, and North America). The 2x male clones were able to produce 2n-pollen grains by a mechanism akin to first-division restitution with crossover (FDR-CO). The estimation of the degree of heterosis for total tuber yield (TTY) was obtained by comparing the field performance of the progenies with their respective 2x and 4x parents. Haulm maturity (HM) and general tuber appearance (GTA) were also evaluated. For TTY, the 4x-2x families (as a group) outyielded both the 4x and 2x parental groups by 10.6% and 42.5%, respectively. In addition, 5 out of 12 famiIies outyielded their corresponding 4x-parents. These best five families outyielded the group of 4x-parents by 40.6%. A considerable variability was observed for HM but, in general, the families were later maturing than the 4x cultivars. The identification of 4x-2x families with GTA within the range of the 4x commercial cultivars was another important observation. An overall lack of parent-offspring correlation was detected indicating that performance of the parents per se cannot provide a reliable prediction about the performance of the families. Therefore, progeny testing would be an imperative step for selection of parental clones at both ploidy levels. Our study indicated that haploid Tuberosum-S. chacoense hybrids are able to generate heterotic 4x-2x families for TTY in combination with good GTA. These results reinforce the view that selection of superior clones for the Northern Hemisphere can be feasible using germplasm with -25% genomic contribution of this wild South American species

Therapeutic Drug Monitoring for Slow Response to Tuberculosis Treatment in a State Control Program, Virginia, USA

TOC summary: Diabetes was associated with increased risk for slow response and low rifampin levels

Tuber yield and quality of 4x-2x (FDR) potato progenies derived from the wild diploid species Solanum berthaultii and Solanum tarijense.

Field experiments were carried out in order to evaluate 4x-2x families derived from crosses between elite 4x potato cultivars and 2x Tuberosum-Solanum tarijense and 2x Tuberosum-Solanum berthaultii clones. Three traits were assessed: total tuber yield (TTY), haulm maturity (HM) and general tuber appearance (GTA). The degree of heterosis of these hybrid families was evaluated by comparison with the respective 2x and 4x parents as well as with seven 4x cultivars. The parental haploid species hybrids derived from S. berthaultii and S. tarijense combined two or more positive horticultural characteristics

Relevance of biotic pathways to the long-term regulation of nuclear waste disposal. Topical report on reference eastern humid low-level sites

The purpose of the work reported here was to develop an order-of-magnitude estimate for the potential dose to man resulting from biotic transport mechanisms at a humid reference low-level waste site in the eastern US. A description of the reference site is presented that includes the waste inventories, site characteristics and biological communites. Parameter values for biotic transport processes are based on data reported in current literature. Transport and exposure scenarios are developed for assessing biotic transport during 500 years following site closure. Calculations of radionuclide decay and waste container decomposition are made to estimate the quantities available for biotic transport. Doses to man are calculated for the biological transport of radionucludes at the reference site after loss of institutional control. These dose estimates are compared to dose estimates we calculated for the intruder-agricultural scenarios reported in the DEIS for 10 CFR 61 (NRC). Dose to man estimates as a result of cumulative biotic transport are calculated to be of the same order-of-magnitude as the dose resulting from the more commonly evaluated human intrusion scenario. The reported lack of potential importance of biotic transport at low-level waste sites in earlier assessment studies is not confirmed by findings presented in this report. Through biotic transport, radionuclides can be moved to locations where they can enter exposure pathways to man

Pharmacokinetics and Dosing of Levofloxacin in Children Treated for Active or Latent Multidrug-resistant Tuberculosis, Federated States of Micronesia and Republic of the Marshall Islands

In the Federated States of Micronesia (FSM) and then the Republic of the Marshall Islands (RMI), levofloxacin pharmacokinetics (PK) were studied in children receiving directly observed once-daily regimens (10 mg/kg, age >5 years; 15–20 mg/kg, age ≤5 years) for either multidrug-resistant tuberculosis (MDR TB) disease or latent infection after MDR TB exposure, to inform future dosing strategies

Comparison of the ‘Denver regimen’ against acute tuberculosis in the mouse and guinea pig

Objectives: In this study, we sought to compare the sterilizing activity of human-equivalent doses of the ‘Denver regimen ’ against acute tuberculosis (TB) infection in the standard mouse model and in the guinea pig. Methods: Pharmacokinetic studies in guinea pigs were used to establish human-equivalent doses for rifampicin, isoniazid and pyrazinamide. Guinea pigs and mice were aerosol-infected with Mycobacterium tuberculosis CDC1551 and treatment was started 2 weeks later with rifampicin/isoniazid/pyrazinamide for up to 6 months. For the first 2 weeks of therapy, the dosing frequency was 5 days/week, and for the remaining period, twice weekly. Treatment was discontinued in groups of 30 mice and 10 guinea pigs at 5 months and at 6 months, and these animals were held for a further 3 months in order to assess relapse rates. Results: Guinea pig lungs became culture-negative after 3 months of predominantly twice-weekly treatment and relapse rates were 0 % (0/10) both after 5 months and after 6 months of treatment. In contrast, all mice remained culture-positive despite 6 months of the same treatment, and 93 % (28/30) and 69 % (20/29) of mice relapsed after treatment for 5 and 6 months, respectively. Conclusions: Treatment with rifampicin/isoniazid/pyrazinamide administered at human-equivalent doses is much more potent against acute TB infection in guinea pigs than in mice. Our findings have importan