Effects of inhibiting CoQ10 biosynthesis with 4-nitrobenzoate in human fibroblasts

Coenzyme Q(10) (CoQ(10)) is a potent lipophilic antioxidant in cell membranes and a carrier of electrons in the mitochondrial respiratory chain. We previously characterized the effects of varying severities of CoQ(10) deficiency on ROS production and mitochondrial bioenergetics in cells harboring genetic defects of CoQ(10) biosynthesis. We observed a unimodal distribution of ROS production with CoQ(10) deficiency: cells with <20% of CoQ(10) and 50-70% of CoQ(10) did not generate excess ROS while cells with 30-45% of CoQ(10) showed increased ROS production and lipid peroxidation. Because our previous studies were limited to a small number of mutant cell lines with heterogeneous molecular defects, here, we treated 5 control and 2 mildly CoQ(10) deficient fibroblasts with varying doses of 4-nitrobenzoate (4-NB), an analog of 4-hydroxybenzoate (4-HB) and inhibitor of 4-para-hydroxybenzoate:polyprenyl transferase (COQ2) to induce a range of CoQ(10) deficiencies. Our results support the concept that the degree of CoQ(10) deficiency in cells dictates the extent of ATP synthesis defects and ROS production and that 40-50% residual CoQ(10) produces maximal oxidative stress and cell death.     

QTL mapping identifies a major locus for resistance in wheat to Sunn pest (<Emphasis Type="Italic">Eurygaster</Emphasis><Emphasis Type="Italic">integriceps</Emphasis>) feeding at the vegetative growth stage

Key message

This research provides the first report of a major locus controlling wheat resistance to Sunn pest. It developed and validated SNP markers that will be useful for marker-assisted selection.

Abstract

Sunn pest (Eurygaster integriceps Puton) is the most destructive insect pest of bread wheat and durum wheat in West and Central Asia and East Europe. Breeding for resistance at the vegetative stage of growth is vital in reducing the damage caused by overwintered adult populations that feed on shoot and leaves of seedlings, and in reducing the next generation of pest populations (nymphs and adults), which can cause damage to grain quality by feeding on spikes. In the present study, two doubled haploid (DH) populations involving resistant landraces from Afghanistan were genotyped with the 90k SNP iSelect assay and candidate gene-based KASP markers. The DH lines and parents were phenotyped for resistance to Sunn pest feeding, using artificial infestation cages at Terbol station, in Lebanon, over three years. Quantitative trait locus (QTL) analysis identified a single major locus on chromosome 4BS in the two populations, with the resistance allele derived from the landrace accessions, IG139431 and IG139883. The QTL explained a maximum of 42 % of the phenotypic variation in the Cham6 × IG139431 and 56 % in the Cham6 × IG139883 populations. SNP markers closest to the QTL showed high similarity to rice genes that putatively encode proteins for defense response to herbivory and wounding. The markers were validated in a large, unrelated population of parental wheat genotypes. All wheat lines carrying the ‘C–G’ haplotype at the identified SNPs were resistant, suggesting that selection based on a haplotype of favourable alleles would be effective in predicting resistance status of unknown genotypes.

     

Association of trace metal elements with lipid profiles in type 2 diabetes mellitus patients: a cross sectional study

Background

It is well known that dyslipidemia and chronic hyperglycemia increase the onset of diabetes and diabetic complication. The aim of this study is to see the association of trace metals elements and lipid profile among type 2 diabetes mellitus patients.

Methods

The study was conducted on 214 type 2 diabetic patients at Jimma University Specialized Hospital, Jimma, Ethiopia. All the eligible study participants responded to the structured interviewer administered questionnaire and fasting venous blood was drawn for biochemical analysis. Trace metal elements (zinc(Zn⁺²), magnesium(Mg⁺²), chromium(Cr⁺³), calcium(Ca⁺²), phosphorus(Po₄ ^?3), manganese(Mn⁺²), copper(Cu⁺²), and iron(Fe⁺³)) and lipid profiles (total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein (HDL-C), and triglycerides (TG)) were measured by atomic absorption spectrophotometry and enzymatic determination method respectively. Data were analyzed by SPSS version 24 software for windows. Bonferroni correction for multiple statistical comparisons was used and a p-value less than 0.01 were accepted as a level of significance.

Result

The mean age of study participants was 42.95(±12.6) with an average of 5.83(±3.1) years being diagnosed with diabetes mellitus. The BMI of female (27.1(±4.9)) was significantly higher than male (25.21(±4.2)). BMI shows positive and significant (p < 0.01) association with lipid profiles (TC, LDL-C, and TG) among type 2 diabetic patients in the liner regression model. In addition, WH-R was positively associated with TG. In Pearson partial correlation adjusted for sex and age, Za⁺² shown to have statistically significant and negative correlations with TC, LDL-C and with TG. Mg⁺² and Cr⁺² negatively and significantly correlated with the lipid profile TC and LDL-C. Ca⁺² negatively correlated with TC and TG. Po^?3 ₄ positively correlated with HDL-C; iron negatively correlated with TC. However, in the liner regression model, only calcium positively and significantly (Beta = ?0.21, p < 0.01) associated with TG.

Conclusion

In the current study, a negative correlation was observed between trace metal elements (Zn⁺², Mg⁺², Cr⁺³, Ca⁺² and Fe⁺³) and lipid profile (TC, LDL-C and TG) among type 2 diabetes mellitus patients. In addition, Ca⁺² observed to be associated with TG. Future studies are highly advised to uncover the bidirectional association between trace metal element and dyslipidemia in diabetic patients.

     

Altered thymidine metabolism due to defects of thymidine phosphorylase.

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive human disease due to mutations in the thymidine phosphorylase (TP) gene. TP enzyme catalyzes the reversible phosphorolysis of thymidine to thymine and 2-deoxy-D-ribose 1-phosphate. We present evidence that thymidine metabolism is altered in MNGIE. TP activities in buffy coats were reduced drastically in all 27 MNGIE patients compared with 19 controls. All MNGIE patients had much higher plasma levels of thymidine than normal individuals and asymptomatic TP mutation carriers. In two patients, the renal clearance of thymidine was approximately 20% that of creatinine, and because hemodialysis demonstrated that thymidine is ultrafiltratable, most of the filtered thymidine is likely to be reabsorbed by the kidney. In vitro, fibroblasts from controls catabolized thymidine in medium; by contrast, MNGIE fibroblasts released thymidine. In MNGIE, severe impairment of TP enzyme activity leads to increased plasma thymidine. In patients who are suspected of having MNGIE, determination of TP activity in buffy coats and thymidine levels in plasma are diagnostic. We hypothesize that excess thymidine alters mitochondrial nucleoside and nucleotide pools leading to impaired mitochondrial DNA replication, repair, or both. Therapies to reduce thymidine levels may be beneficial to MNGIE patients.     

In vitro regeneration and transformation of pigeonpea [Cajanus cajan (L.) Millsp]

A requirement for generating transgenic pigeonpea [Cajanuscajan (L.) Millsp] plants is the development of a highly efficientin vitro regeneration procedure. This goal was achieved byusing germinated seedlings grown on B5 medium supplemented with 10 mgl^–1 6-benzylaminopurine, which induced differentiatingcallus formation in the cotyledonary node region. The calli were transferred onB5 medium with 0.2 mg l^–1 6-benzylaminopurine toobtain shoot induction. Elongated shoots were then further cultured on a B5hormone-free medium for rooting. Using this regeneration system transgenicpigeonpea plants were obtained both by particle bombardment andAgrobacterium tumefaciens-mediated gene transfer. Thepresence of the transgenes in the pigeonpea genome was confirmed by GUS assays,PCR and Southern hybridisation. The transgenic rooted plants were successfullytransferred to soil in the greenhouse. GUS and PCR assays of T1 progeniesconfirmed that the transgenes were stably transmitted to the next generation.This is the first report of successful use ofAgrobacteriumas well as particle bombardment for production of transgenic pigeonpea plants.     

Community-based prevalence of rheumatic heart disease in rural Ethiopia: Five-year follow-up

BackgroundAs little is known about the prevalence and clinical progression of subclinical (latent) rheumatic heart disease (RHD) in sub-Saharan Africa, we report the results of a 5 year follow-up of a community based, echocardiographic study of the disease, originally carried out in a rural area around Jimma, Ethiopia.MethodsIndividuals with evidence of RHD detected during the baseline study as well as controls and their family members were screened with a short questionnaire together with transthoracic echocardiography.ResultsOf 56 individuals with RHD (37 definite and 19 borderline) in the original study, 36 (26 definite and 10 borderline) were successfully located 57.3 (range 44.9–70.7) months later. At follow-up two thirds of the definite cases still had definite disease; while a third had regressed. Approximately equal numbers of the borderline cases had progressed and regressed. Features of RHD had appeared in 5 of the 60 controls. There was an increased risk of RHD in the family relatives of borderline and definite cases (3.8 and 4.0 times respectively), notably among siblings. Compliance with penicillin prophylaxis was very poor.ConclusionsWe show the persistence of echocardiographically demonstrable RHD in a rural sub-Saharan population. Both progression and regression of the disease were found; however, the majority of the individuals who had definite features of RHD had evidence of continuing RHD lesions five years later. There was an increased risk of RHD in the family relatives of borderline and definite cases, notably among siblings. The findings highlight the problems faced in addressing the problem of RHD in the rural areas of sub-Saharan Africa. They add to the evidence that community-based interventions for RHD will be required, together with appropriate ways of identifying active disease, achieving adequate penicillin prophylaxis and developing vaccines for primary prevention.     

Response of corn to combinations of atrazine, propyl gallate and ozone

Growth chamber experiments were conducted to determine the influence of the air pollutant ozone (O₃) [0.2 and 0.3 ppm (v/v)] on the growth of corn (Zea mays L.) treated with the herbicide atrazine (2.5 and 3.5 kg/ha) and the antioxidant propyl gallate (5 and 8 kg/ha). At both concentrations O₃ at 0.3 ppm alone reduced dry weights of corn and chlorophyll. Chlorophyll a was more affected than chlorophyll b by O₃ at 0.3 ppm alone and in combination with atrazine. Propyl gallate at both rates protected corn against O₃ injury. The interaction between atrazine and O₃ at 0.2 ppm was additive whereas at 0.3 ppm it was antagonistic. But combinations of atrazine and propyl gallate did not protect corn from O₃ injury.     

‘If an Eye Is Washed Properly,It Means It Would See Clearly’: A Mixed Methods Study of Face Washing Knowledge,Attitudes, and Behaviors in Rural Ethiopia

BackgroundFace cleanliness is a core component of the SAFE (Surgery, Antibiotics, Facial cleanliness, and Environmental improvements) strategy for trachoma control. Understanding knowledge, attitudes, and behaviors related to face washing may be helpful for designing effective interventions for improving facial cleanliness.MethodsIn April 2014, a mixed methods study including focus groups and a quantitative cross-sectional study was conducted in the East Gojjam zone of the Amhara region of Ethiopia. Participants were asked about face washing practices, motivations for face washing, use of soap (which may reduce bacterial load), and fly control strategies.ResultsOverall, both knowledge and reported practice of face washing was high. Participants reported they knew that washing their own face and their children’s faces daily was important for hygiene and infection control. Although participants reported high knowledge of the importance of soap for face washing, quantitative data revealed strong variations by community in the use of soap for face washing, ranging from 4.4% to 82.2% of households reporting using soap for face washing. Cost and forgetfulness were cited as barriers to the use of soap for face washing. Keeping flies from landing on children was a commonly cited motivator for regular face washing, as was trachoma prevention.ConclusionsInterventions aiming to improve facial cleanliness for trachoma prevention should focus on habit formation (to address forgetfulness) and address barriers to the use of soap, such as reducing cost. Interventions that focus solely on improving knowledge may not be effective for changing face-washing behaviors.     

The phytomelanin layer in traditional members of Bidens and Coreopsis and phylogeny of the Coreopsideae (Compositae)

The phytomelanin layer on the pericarp of cypselae (achenes) of many members of traditional Bidens and Coreopsis, both considered polyphyletic, was studied with the help of scanning electron (SEM) and light (LM) microscopes. It is found to be more prominent in taxa kept within Bidens than in Coreopsis. The black ‘peg‐like’ phytomelanin found in traditional members of Bidens is also found in some members of Coreopsis. Some traditional members of Coreopsis display distinctive pericarp morphology but lack phytomelanin. The pericarp in Bidens is striated, i.e. it is interrupted by longitudinal bands of parenchyma through which the embryo emerges during seed germination. No striation was found in cypselae of traditional Coreopsis. Emergence of the seed in taxa with this type of pericarp morphology is observed to be by rupturing the carpel wall along the sutures. Characteristic morphology of the phytomelanin layer and other cellular secretions on the pericarp in representative species of these genera and segregates as well as the probable adaptive value of this layer and that of the parenchyma is discussed. Coreopsis sect. Tuckermannia (Nutt.) Blake, C. sect. Pugiopappus (A. Gray) Blake, and C. sect. Euleptosyne (A. Gray) Blake, are elevated to the genus Leptosyne DC., while Coreopsis sect. Electra (DC.) Blake is returned to Electra DC. A key to the segregate genera and the remaining sections of Coreopsis as well as new combinations and synonyms are provided.