320 research outputs found

    Anthocyanin production as a potential visual selection marker during plant transformation

    Get PDF
    A mutant allele of the transcription factor gene MYB10 from apple induces anthocyanin production throughout the plant. This gene, including its upstream promoter, gene coding region and terminator sequence, was introduced into apple, strawberry and potato plants to determine whether it could be used as a visible selectable marker for plant transformation as an alternative to chemically selectable markers, such as kanamycin resistance. After transformation, red coloured calli, red shoots and red well-growing plants were scored. Red and green shoots were harvested from apple explants and examined for the presence of the MYB10 gene by PCR analysis. Red shoots of apple explants always contained the MYB10 gene but not all MYB10 containing shoots were red. Strawberry plants transformed with the MYB10 gene showed anthocyanin accumulation in leaves and roots. No visible accumulation of anthocyanin could be observed in potato plants grown in vitro, even the ones carrying the MYB10 gene. However, acid methanol extracts of potato shoots or roots carrying the MYB10 gene contained up to four times higher anthocyanin content than control plants. Therefore anthocyanin production as result of the apple MYB10 gene can be used as a selectable marker for apple, strawberry and potato transformation, replacing kanamycin resistance

    Species distribution and in vitro antifungal susceptibility of oral yeast isolates from Tanzanian HIV-infected patients with primary and recurrent oropharyngeal candidiasis

    Get PDF
    \ud In Tanzania, little is known on the species distribution and antifungal susceptibility profiles of yeast isolates from HIV-infected patients with primary and recurrent oropharyngeal candidiasis. A total of 296 clinical oral yeasts were isolated from 292 HIV-infected patients with oropharyngeal candidiasis at the Muhimbili National Hospital, Dar es Salaam, Tanzania. Identification of the yeasts was performed using standard phenotypic methods. Antifungal susceptibility to fluconazole, itraconazole, miconazole, clotrimazole, amphotericin B and nystatin was assessed using a broth microdilution format according to the guidelines of the Clinical and Laboratory Standard Institute (CLSI; M27-A2). Candida albicans was the most frequently isolated species from 250 (84.5%) patients followed by C. glabrata from 20 (6.8%) patients, and C. krusei from 10 (3.4%) patients. There was no observed significant difference in species distribution between patients with primary and recurrent oropharyngeal candidiasis, but isolates cultured from patients previously treated were significantly less susceptible to the azole compounds compared to those cultured from antifungal naïve patients. C. albicans was the most frequently isolated species from patients with oropharyngeal candidiasis. Oral yeast isolates from Tanzania had high level susceptibility to the antifungal agents tested. Recurrent oropharyngeal candidiasis and previous antifungal therapy significantly correlated with reduced susceptibility to azoles antifungal agents.\u

    The distribution of burden of dental caries in schoolchildren: a critique of the high-risk caries prevention strategy for populations

    Get PDF
    BACKGROUND: The 'high-risk approach' is a commonly adopted strategy recommended for the prevention of dental caries in populations. The scientific basis for the strategy has been questioned. The objective of this study is to assess the contribution that children identified at 'high-risk' made towards the total of new caries lesions over a 4-year period, by analysing the distribution of new lesions per 100 children. METHODS: Data are from the National Preventive Dentistry Demonstration Programme (NPDDP) in the United States. The analyses identified the distribution of new carious lesions over a 4-year period in four groups of 7 year-old children who received differing preventive regimes. RESULTS: The majority of new lesions occurred in those children classified at lowest caries risk at baseline. Irrespective of the preventive regime adopted and the initial caries levels, children classified as 'highest risk' contributed less than 6% of the total number of new lesions developing over 4 years. CONCLUSION: These findings challenge the basis for the adoption of a high-risk strategy

    Elevated temperatures and longer durations improve the efficacy of oxaliplatin- and mitomycin C-based hyperthermic intraperitoneal chemotherapy in a confirmed rat model for peritoneal metastasis of colorectal cancer origin

    Get PDF
    Introduction: In patients with limited peritoneal metastasis (PM) originating from colorectal cancer, cytoreductive surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) is a potentially curative treatment option. This combined treatment modality using HIPEC with mitomycin C (MMC) for 90 minutes proved to be superior to systemic chemotherapy alone, but no benefit of adding HIPEC to CRS alone was shown using oxaliplatin-based HIPEC during 30 minutes. We investigated the impact of treatment temperature and duration as relevant HIPEC parameters for these two chemotherapeutic agents in representative preclinical models. The temperature- and duration- dependent efficacy for both oxaliplatin and MMC was evaluated in an in vitro setting and in a representative animal model. Methods: In 130 WAG/Rij rats, PM were established through i.p. injections of rat CC-531 colon carcinoma cells with a signature similar to the dominant treatment-resistant CMS4 type human colorectal PM. Tumor growth was monitored twice per week using ultrasound, and HIPEC was applied when most tumors were 4-6 mm. A semi-open four-inflow HIPEC setup was used to circulate oxaliplatin or MMC through the peritoneum for 30, 60 or 90 minutes with inflow temperatures of 38°C or 42°C to achieve temperatures in the peritoneum of 37°C or 41°C. Tumors, healthy tissue and blood were collected directly or 48 hours after treatment to assess the platinum uptake, level of apoptosis and proliferation and to determine the healthy tissue toxicity. Results: In vitro results show a temperature- and duration- dependent efficacy for both oxaliplatin and MMC in both CC-531 cells and organoids. Temperature distribution throughout the peritoneum of the rats was stable with normothermic and hyperthermic average temperatures in the peritoneum ranging from 36.95-37.63°C and 40.51-41.37°C, respectively. Treatments resulted in minimal body weight decrease (&lt;10%) and only 7/130 rats did not reach the endpoint of 48 hours after treatment. Conclusions: Both elevated temperatures and longer treatment duration resulted in a higher platinum uptake, significantly increased apoptosis and lower proliferation in PM tumor lesions, without enhanced normal tissue toxicity. Our results demonstrated that oxaliplatin- and MMC-based HIPEC procedures are both temperature- and duration-dependent in an in vivo tumor model.</p

    Mismatch repair deficiency and MUTYH variants in small intestine-neuroendocrine tumors

    Get PDF
    & nbsp;Small intestine-neuroendocrine tumors (SI-NETs) are one of the most common tumors of the small bowel. Despite an increasing incidence, the exact mechanisms driving underlying pathology remain to be determined. Interestingly, recent studies linked the development of (SI-)NETs to both Lynch syndrome (LS) and MUTYH variants. If confirmed, these associations would have important consequences for treatment. In this study we therefore investigated the prevalence of mismatch repair (MMR) deficiency and MUTYH variants in 64 primary resected SI-NETs. Immunohistochemistry was used to assess the expression of the MMR genes, and competitive allele-specific PCR (KASPar) targeting two hotspot MUTYH variants [p.(Tyr179Cys), p.(Gly396Asp)] was performed to determine their prevalence in SI-NETs. Strikingly, all 64 SI-NETs stained positive for MSH6 and PMS2, indicating & nbsp;MMR proficiency. In addition, no MUTYH hotspot variant was found in any of the 64 SI-NETs. As such, these results do not support an association between SI-NET development and LS or MUTYH variants. In order to gain insight into SI-NET pathogenesis and optimally manage patients, future research should therefore focus on other candidate genes. (C) 2022 Published by Elsevier IncMTG2 - Moleculaire genetica van gastrointestinale tumorenMolecular tumour pathology - and tumour genetic

    Ebstein’s anomaly may be caused by mutations in the sarcomere protein gene MYH7

    Get PDF
    Ebstein's anomaly is a rare congenital heart malformation characterised by adherence of the septal and posterior leaflets of the tricuspid valve to the underlying myocardium. Associated abnormalities of left ventricular morphology and function including left ventricular noncompaction (LVNC) have been observed. An association between Ebstein's anomaly with LVNC and mutations in the sarcomeric protein gene MYH7, encoding β-myosin heavy chain, has been shown by recent studies. This might represent a specific subtype of Ebstein's anomaly with a Mendelian inheritance pattern. In this review we discuss the association of MYH7 mutations with Ebstein's anomaly and LVNC and its implications for the clinical care for patients and their family members.Congenital Heart Diseas

    Pharmacotherapy-Based Problems in the Management of Diabetes Mellitus: Needs Much More to be Done!

    Get PDF
    A total of 856 diabetic patients were evaluated for pharmacotherapy-based problems like for possible drug interactions, adverse drug reactions, and other mismatches, if any. Poor correlation between the advised insulin therapy and patients’ fasting blood glucose levels (12%, n=103) was observed. To most of the patients (41.66%, n= 357), insulin therapy was advised in combination with glucocorticoides, thiazides diuretics, and propranolol. Prescribing beta blocker (propranolol) with insulin is contraindicated. The higher incidence of diabetic foot patients was in the mean age of 57±3.4 years that was controlled with combination therapy of insulin and oral antidiabetics (63.0%, n=516). 11.1% of the treated patients could not take the prescribed therapy due to poor acceptance of insulin therapy due to its syringe needle prick. 41.66% risks of potential drug interactions, 7.93% adverse drug reactions, and 6.6% mismatches were recorded, as per the international approved algorithm, for managing a diabetes mellitus that reflects poor health care system. All these events necessitate for coordinating with other health professionals to make the therapy safer in the better interest of the patients. It is concluded that in practice prescribing pattern carries more risks for patients. It is imperative to improve the practice of pharmacotherapeutics rather than to practice in routine

    Relative contribution of mutations in genes for autosomal dominant distal hereditary motor neuropathies: a genotype-phenotype correlation study

    Get PDF
    Distal hereditary motor neuropathy (HMN) is a clinically and genetically heterogeneous group of disorders affecting spinal α-motor neurons. Since 2001, mutations in six different genes have been identified for autosomal dominant distal HMN; glycyl-tRNA synthetase (GARS), dynactin 1 (DCTN1), small heat shock 27 kDa protein 1 (HSPB1), small heat shock 22 kDa protein 8 (HSPB8), Berardinelli-Seip congenital lipodystrophy (BSCL2) and senataxin (SETX). In addition a mutation in the (VAMP)-associated protein B and C (VAPB) was found in several Brazilian families with complex and atypical forms of autosomal dominantly inherited motor neuron disease. We have investigated the distribution of mutations in these seven genes in a cohort of 112 familial and isolated patients with a diagnosis of distal motor neuropathy and found nine different disease-causing mutations in HSPB8, HSPB1, BSCL2 and SETX in 17 patients of whom 10 have been previously reported. No mutations were found in GARS, DCTN1 and VAPB. The phenotypic features of patients with mutations in HSPB8, HSPB1, BSCL2 and SETX fit within the distal HMN classification, with only one exception; a C-terminal HSPB1-mutation was associated with upper motor neuron signs. Furthermore, we provide evidence for a genetic mosaicism in transmitting an HSPB1 mutation. This study, performed in a large cohort of familial and isolated distal HMN patients, clearly confirms the genetic and phenotypic heterogeneity of distal HMN and provides a basis for the development of algorithms for diagnostic mutation screening in this group of disorder
    corecore