Some aspects of the biology and behaviour of Sesamia nonagrioides botanephaga Tams and Bowden (Lepidoptera: Noctuidae), a major stem borer pest of maize in Southern Ghana

Studies were conducted on the stemborer, Sesamia nonagrioides botanephaga Tams and Bowden (Lepidoptera: Noctuidae), which is a pest of increasing importance on maize in Ghana, to elucidate some aspects of its biology and behaviour in southern Ghana. The pest was more abundant in the minor season than in the major season. The life cycle revealed 10 developmental stages, namely the egg, six larval instars, prepupa and pupa. A female S. n. botanephaga laid eggs within a period of 5 days. The eggs were deposited on the inner side of the leaf sheath fitting tightly onto the maize stem. The mated females laid more eggs per female (330 + 17.7 eggs) than the virgin females (268 + 9.2 eggs). The incubation period of the eggs was 5.23 + 0.03 (5-7) days. The mean larval duration was 29 days and the prepupal period lasted for 1–3 days. The first instar larvae dispersed within 1–3 days after hatching. The third, fourth, fifth, and sixth instar larvae fed actively on maize stalk producing large quantities of frass. The pupal period varied from 6 to 10 days. The life cycle was completed in an average of 35.2 (26-51) days. Adults of S. n. botanephaga lived for between 4–10 days. The adults reared in the laboratory showed a sex ratio of 2:3 (male : female), which was significantly different from the expected ratio (1:1). The implications of these findings are discussed in relation to the effective management of the pest in Ghana

The role of elective neck dissection during surgical salvage for recurrent nasopharyngeal carcinoma

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Expression of Epstein-Barr virus-encoded BamH1-A rightward transcript 7 microRNA in nasopharyngeal carcinoma cells modulates the responsive to irradiation treatment

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Induction of the stringent response in staphylococcus aureus by mupirocin and its effect on global transcription and virulence factors

Staphylococcus aureus is a major pathogen in both hospital and community settings and it causes infections ranging from mild skin and wound infections to life-threatening systemic illness and, together with the emergence of antibiotic resistance, has been a major cause of morbidity and mortality worldwide. The stringent response, is a stress response that bacteria display to avoid death when subjected to amino-acid starvation. This phenomenon has been observed in different species among Gram positive and Gram negative bacteria but relatively few studies have observed the stress response in Staphylococcus aureus. The stringent response can be triggered by treatment with mupirocin, an antibiotic that mimics amino-acid starvation by inhibiting isoleucyl tRNA synthetase.In this project S. aureus 8325-4 was exposed to sub-inhibitory concentrations of mupirocin (0.5 MIC = 0.25µg/ml-1) to investigate the ability of this concentration to trigger the stringent response. The treatment with mupirocin was continued up to 24 h as previous studies only examined short periods of treatment. Growth was inhibited and the stringent response nucleotide ppGpp was detected 1 h after treatment which slowly decreased in concentration for up to 4 h combined with significant growth inhibition. However, ppGpp could not be detected at 12 or 24 h whereas growth resumed.In addition, the effect of sub-inhibitory concentrations of mupirocin was observed on the TSST-1 producing S. aureus clinical strain (B49). Q-PCR showed up-regulation of tst gene, codes for TSST-1, and its regulator RNAIII transcription up to 8 h of exposure relative to controls, the toxin was not detected by Reverse Passive Latex Assay.Further, RNA-seq analysis was used to observe the global transcriptional alterations caused by the stringent response in S. aureus at 1, 12 and 24 h. From the whole transcriptome profile, differentially expressed genes relative to control as well as from comparisons between treated cell time points were observed concentrating on 60 virulence genes and stress related genes that were significantly increased through stringent response status (1 h). Although ppGpp was not detected at 12 h, cells were still under the influence of the stringent response. However, cell growth had resumed by 24 h which indicates recovery after exposure to sub-lethal concentrations of mupirocin. The effect of the sub-inhibitory concentration of mupirocin on global gene expression in S. aureus is discussed in relation to global control of gene expression and clinical use. In addition, a scenario for S. aureus recovery from stringent response has been suggested here which might open doors for drug target determination in the future

Hypoxia in head and neck squamous cell carcinoma

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The diagnostic value of methylated DNA in laryngeal squamous cell carcinoma: meta-analysis

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Singleton birth after preimplantation genetic diagnosis for Huntington disease using whole genome amplification

Objective: To report a successful case of preimplantation genetic diagnosis (PGD) for Huntington disease using whole genome amplification. Design: Case report. Setting: University assisted reproduction unit. Patient(s): A couple with family history of Huntington disease: The husband was carrying the expanded allele of the IT15 gene, and the wife had the normal allele. Intervention(s): Preimplantation genetic diagnosis with whole genome amplification for identification of genetically normal embryos. Main Outcome Measure(s): Live birth. Result(s): In an IVF cycle, 15 oocytes were retrieved, of which 13 were mature and 11 were fertilized. On day 3, embryo biopsy and PGD were performed on ten good-quality embryos. Multiple displacement amplification was conducted, followed by polymerase chain reaction with fluorescence primers. Three pairs of primers were used for the amplification of the IT15 gene at the: 1) trinucleotide expansion site; 2) trinucleotide expansion site plus the polymorphic site situated on its 3′-end; and 3) polymorphic marker located downstream of the trinucleotide repeats. Two normal blastocysts were replaced on day 5 and another two good-quality blastocysts were cryopreserved. The woman gave birth to a normal baby girl whose normal genetic status was confirmed by prenatal diagnosis. Conclusion(s): Whole genome amplification by multiple displacement amplification can be used for PGD of Huntington disease. © 2009 American Society for Reproductive Medicine.postprin