Cytogenetic studies on some Nigerian species of Solanum L. (Solanaceae)

Cytogenetic studies to determine the chromosome number, structure and behaviour of some species of Solanum in Nigeria were carried out. Attempt was also made to induce polyploidy in the species. Comparative analysis of the cytological behaviour of the diploid and polyploid cytotypes was made.The studies show that the somatic chromosome number in the genus Solanum is 2n = 24. Colchiploidisation produced tetraploids with 2n = 48 and aneuploids with 2n = 69. The karyotype analysis indicates that the chromosomes were generally very small. There were also slight variations incentromeric positions and arm lengths. Meiotic behaviour of the chromosomes involved a combination of bivalent and multivalent associations especially at the polyploid levels. The significance of this work in the understanding of cytogenetic behaviour of plants and crop improvement efforts are discusse

Targeted mutagenesis in Vigna unguiculata (L.) Walp. and Cucumeropsis mannii (NAUD) in Nigeria

The mutagenic effects of 0.2% aqueous solution of colchicine on gross and micromophological features of seedlings of Vigna unguiculata (L) Walp. and Cucumeropsis mannii (Naud.) were investigated.Terminal buds of two-week old seedlings were assaulted with 0.2% colchicine by the cotton plug and micro syringe methods and performances were monitored until maturity. Colchicine-treated V.unguicu-lata seedlings were observed to grow slower, had malformed leaves, flowered late and produced less number of seeds per pod than the control. Mean values of features like stomatal indiceson both the abaxial and adaxial surfaces, terminal leaflet dimensions and trichome distribution between the treated and control were found to be significantly different. In contrast, treated seedlings of C.mannii flowered and fruited earlier than the case of control material. However, growth was also slowed down by the treatment while features like stomatal indices and trichome distribution were notsignificantly different. The results here have shown that apart from doubling of chromosomes, colchicine can also be used to induce other mutagenic changes which may be of agronomic utility

Tracking sexual dimorphism in Telfairia occidentalis Hooker f. (Cucurbitaceae) with morphological and molecular markers

Morphological (foliar features) and molecular (DNA fingerprinting) markers were used to characterize sexual dimorphism in Telfairia occidentalis Hook. f. (Cucurbitaceae). A total of thirty strains comprising fifteen males and fifteen females from market-sourced fruits bred to the third generation were used forthe investigation. The amplified fragment length polymorphism (AFLP) technique was combined with silver staining to determine the level of DNA polymorphism in the strains. Results showed that the females were generally larger in size than the males in leaf morphological features, while DNAfingerprints revealed the existence of polymorphism in the plant. However, this genetic variability did not clearly correspond with presence of sexual dimorphism in the species. The implications of these results in understanding the genetics, breeding and conservation of the plant’s germplasm arediscussed

Pooled analysis of WHO Surgical Safety Checklist use and mortality after emergency laparotomy

Background The World Health Organization (WHO) Surgical Safety Checklist has fostered safe practice for 10 years, yet its place in emergency surgery has not been assessed on a global scale. The aim of this study was to evaluate reported checklist use in emergency settings and examine the relationship with perioperative mortality in patients who had emergency laparotomy. Methods In two multinational cohort studies, adults undergoing emergency laparotomy were compared with those having elective gastrointestinal surgery. Relationships between reported checklist use and mortality were determined using multivariable logistic regression and bootstrapped simulation. Results Of 12 296 patients included from 76 countries, 4843 underwent emergency laparotomy. After adjusting for patient and disease factors, checklist use before emergency laparotomy was more common in countries with a high Human Development Index (HDI) (2455 of 2741, 89.6 per cent) compared with that in countries with a middle (753 of 1242, 60.6 per cent; odds ratio (OR) 0.17, 95 per cent c.i. 0.14 to 0.21, P <0001) or low (363 of 860, 422 per cent; OR 008, 007 to 010, P <0.001) HDI. Checklist use was less common in elective surgery than for emergency laparotomy in high-HDI countries (risk difference -94 (95 per cent c.i. -11.9 to -6.9) per cent; P <0001), but the relationship was reversed in low-HDI countries (+121 (+7.0 to +173) per cent; P <0001). In multivariable models, checklist use was associated with a lower 30-day perioperative mortality (OR 0.60, 0.50 to 073; P <0.001). The greatest absolute benefit was seen for emergency surgery in low- and middle-HDI countries. Conclusion Checklist use in emergency laparotomy was associated with a significantly lower perioperative mortality rate. Checklist use in low-HDI countries was half that in high-HDI countries.Peer reviewe