Superparamagnetic iron oxide nanoparticle attachment on array of micro test tubes and microbeakers formed on p-type silicon substrate for biosensor applications

A uniformly distributed array of micro test tubes and microbeakers is formed on a p-type silicon substrate with tunable cross-section and distance of separation by anodic etching of the silicon wafer in N, N-dimethylformamide and hydrofluoric acid, which essentially leads to the formation of macroporous silicon templates. A reasonable control over the dimensions of the structures could be achieved by tailoring the formation parameters, primarily the wafer resistivity. For a micro test tube, the cross-section (i.e., the pore size) as well as the distance of separation between two adjacent test tubes (i.e., inter-pore distance) is typically approximately 1 μm, whereas, for a microbeaker the pore size exceeds 1.5 μm and the inter-pore distance could be less than 100 nm. We successfully synthesized superparamagnetic iron oxide nanoparticles (SPIONs), with average particle size approximately 20 nm and attached them on the porous silicon chip surface as well as on the pore walls. Such SPION-coated arrays of micro test tubes and microbeakers are potential candidates for biosensors because of the biocompatibility of both silicon and SPIONs. As acquisition of data via microarray is an essential attribute of high throughput bio-sensing, the proposed nanostructured array may be a promising step in this direction

Blended learning in undergraduate dental education: a global pilot study.

AIMS: To explore the global trends in blended learning in undergraduate dental education during the COVID pandemic and during the recovery phase by engaging with the students and faculty and evaluate the implications for dental education in the post-COVID era. METHODS: It was a pilot cross-sectional study which employed a convenience sampling technique to recruit representatives of dental faculty and undergraduate students in 80 dental institutions globally. A previously validated questionnaire consisting of a combination of closed and open-ended items was used for data collection. Responses to these online questionnaires were processed and analysed using the R statistical computing environment. RESULTS: A total of 320 dental students and 169 faculty members from 47 different dental institutions participated in the study. Video and Live Online Tutorials were considered to be the most effective method of online learning followed by online question banks by both groups. Significant differences were noted between faculty and students regarding time spent and effectiveness of online teaching and learning, respectively, both before and after the start of COVID. The results highlight the faculty need to engage more closely with the students to address their learning needs. Finally, the participants provided several recommendations regarding the future development of teaching and learning strategies as well as assessments in the post-pandemic era. CONCLUSIONS: This is the first study which explores blended learning in dental education with participants from multiple institutions in different regions of the globe. Compared to the faculty, students considered online learning to be less interactive and preferred learning activities and all assessments to be delivered face-to-face. The results underscore the need to adapt teaching practices to suit the learning needs of the students

Potential use of the Bushmint, Hyptis suaveolens, for the Control of Infestation by the Pink Stalk Borer, Sesamia calamistis on Maize in Southern Benin, West Africa

Maize production in Benin, especially in resource-poor farmers' fields, is constrained by stemborers among other factors. One of the major stemborers in southern Benin is Sesamia calamistis Hampson (Lepidoptera: Noctuidae). African farmers cannot afford to use commercial insecticides for controlling stemborers - they are expensive and unsuitable for durable pest management systems due to eco-toxicity. There is therefore a need for cheaper and environmentally friendly methods and botanicals offer an attractive alternative. The bushmint, Hyptis suaveolens (L.) Poit. (Lamiales: Lamiaceae), was compared with the commercial insecticide Furadan (carbofuran) for the control of S. calamistis on maize Zea mays L. (Poales: Poaceae). Trials were conducted in the screenhouse and in the field during the minor cropping season in 2004 at the International Institute of Tropical Agriculture (IITA)-Benin station. The variables measured included numbers of egg masses per plant, eggs per egg mass (in the screenhouse study), population density of S. calamistis, percentage of infested plants and/or ears, and deadhearts in the field. Irrespective of the variable considered, the aqueous extract of H. suaveolens compared favorably with Furadan while maize surrounded by live H. suaveolens plants had lower S. calamistis densities

The use of sleep aids among Emergency Medicine residents: a web based survey

BACKGROUND: Sleepiness is a significant problem among residents due to chronic sleep deprivation. Recent studies have highlighted medical errors due to resident sleep deprivation. We hypothesized residents routinely use pharmacologic sleep aids to manage their sleep deprivation and reduce sleepiness. METHODS: A web-based survey of US allopathic Emergency Medicine (EM) residents was conducted during September 2004. All EM residency program directors were asked to invite their residents to participate. E-mail with reminders was used to solicit participation. Direct questions about use of alcohol and medications to facilitate sleep, and questions requesting details of sleep aids were included. RESULTS: Of 3,971 EM residents, 602 (16%) replied to the survey. Respondents were 71% male, 78% white, and mean (SD) age was 30 (4) years, which is similar to the entire EM resident population reported by the ACGME. There were 32% 1st year, 32% 2nd year, 28% 3rd year, and 8% 4th year residents. The Epworth Sleepiness Scale (ESS) showed 38% of residents were excessively sleepy (ESS 11–16) and 7% were severely sleepy (ESS>16). 46% (95 CI 42%–50%) regularly used alcohol, antihistamines, sleep adjuncts, benzodiazepines, or muscle relaxants to help them fall or stay asleep. Study limitations include low response and self-report. CONCLUSION: Even with a low response rate, sleep aid use among EM residents may be common. How this affects performance, well-being, and health remains unknown

Longitudinal Evaluation of the Hypothalamic-Pituitary-Testicular Function in 8 Boys with Adrenal Hypoplasia Congenita (AHC) Due to NR0B1 Mutations

BACKGROUND:Boys carrying mutations in the NR0B1 gene develop adrenal hypoplasia congenita (AHC) and impaired sexual development due to the combination of hypogonadotropic hypogonadism (HH) and primary defects in spermatogenesis. METHODS:We analysed the evolution of hypothalamic-pituitary-testicular function of 8 boys with AHC due to NR0B1 mutations. Our objective was to characterize and monitor the progressive deterioration of this function. RESULTS:The first symptoms appeared in the neonatal period (n = 5) or between 6 months and 8.7 years (n = 3). Basal plasma adrenocorticotrophic hormone (ACTH) concentrations increased in all boys, whilst cortisol levels decreased in one case. The natremia was equal or below 134 mmol/L and kaliemia was over 5 mmol/L. All had increased plasma renin. In 3 of 4 patients diagnosed in the neonatal period and evaluated during the first year, the basal plasma gonadotropins concentrations, and their response to gonadotropin releasing hormone (GnRH) test (n = 2), and those of testosterone were normal. The plasma inhibin B levels were normal in the first year of life. With the exception of two cases these concentrations decreased to below the normal for age. Anti-Müllerian hormone concentrations were normal for age in all except one case, which had low concentrations before the initiation of testosterone treatment. In 3 of the 8 cases the gene was deleted and the remaining 5 cases carried frameshift mutations that are predicted to introduce a downstream nonsense mutation resulting in a truncated protein. CONCLUSIONS:The decreases in testosterone and inhibin B levels indicated a progressive loss of testicular function in boys carrying NR0B1 mutations. These non-invasive examinations can help to estimate the age of the testicular degradation and cryopreservation of semen may be considered in these cases as investigational procedure with the aim of restoring fertility

Effect of growth hormone replacement therapy in a boy with Dent's disease: a case report

<p>Abstract</p> <p>Introduction</p> <p>Dent's disease is an X-linked recessive proximal tubulopathy characterized by low molecular weight proteinuria, hypercalciuria, nephrocalcinosis, nephrolithiasis and progressive renal failure. To the best of our knowledge, this is only the third report on the use of growth hormone therapy in a child with poor growth associated with Dent's disease.</p> <p>Case presentation</p> <p>We report on a 7-year-old Montenegrin boy with proteinuria, hypercalciuria, nephrocalcinosis, rickets and short stature with unimpaired growth hormone secretion. A molecular genetic analysis showed S244L substitution on the CLCN5 gene. After two years of conventional treatment with hydrochlorothiazide, laboratory tests revealed more prominent proteinuria, mild hypophosphatemia, increased values of alkaline phosphatase and features of rickets. Phosphate salts, calcitriol, potassium citrate and growth hormone were included in the therapy. After three years of therapy, his adjusted parental stature was 1.53 standard deviations higher than at the initiation of growth hormone therapy. His global kidney functions and levels of proteinuria and calciuria remained relatively stable. In spite of the growth hormone therapy, his tubular reabsorption of phosphate deteriorated.</p> <p>Conclusion</p> <p>Treatment with recombinant human growth hormone may have a positive effect on final height in poorly growing children with Dent's disease and hypophosphatemic rickets. However, it is not possible to reach definite conclusions due to the small sample within the literature and the brief duration of the therapy.</p

Diagnosis of pericardial cysts using diffusion weighted magnetic resonance imaging: A case series

<p>Abstract</p> <p>Introduction</p> <p>Congenital pericardial cysts are benign lesions that arise from the pericardium during embryonic development. The diagnosis is based on typical imaging features, but atypical locations and signal magnetic resonance imaging sequences make it difficult to exclude other lesions. Diffusion-weighted magnetic resonance imaging is a novel method that can be used to differentiate tissues based on their restriction to proton diffusion. Its use in differentiating pericardial cysts from other pericardial lesions has not yet been described.</p> <p>Case presentation</p> <p>We present three cases (a 51-year-old Caucasian woman, a 66-year-old Caucasian woman and a 77-year-old Caucasian woman) with pericardial cysts evaluated with diffusion-weighted imaging using cardiac magnetic resonance imaging. Each lesion demonstrated a high apparent diffusion coefficient similar to that of free water.</p> <p>Conclusion</p> <p>This case series is the first attempt to investigate the utility of diffusion-weighted magnetic resonance imaging in the assessment of pericardial cysts. Diffusion-weighted imaging may be a useful noninvasive diagnostic tool for pericardial cysts when conventional imaging findings are inconclusive.</p

Isolation and Partial Characterisation of a Novel Lectin from Aegle marmelos Fruit and Its Effect on Adherence and Invasion of Shigellae to HT29 Cells

Lectins are a class of ubiquitous proteins/glycoproteins that are abundantly found in nature. Lectins have unique carbohydrate binding property and hence have been exploited as drugs against various infectious diseases. We have isolated one such novel lectin from the fruit pulp of Aegle marmelos. The isolated lectin was partially characterised and its effect against Shigella dysenteriae infection was evaluated. The isolated lectin was found to be a dimeric protein with N-acetylgalactosamine, mannose and sialic acid binding specificity. The effect of Aegle marmelos fruit lectin on the adherence of Shigella dysenteriae to human colonic epithelial cells (HT29 cells) was evaluated by Enzyme Linked Immune Sorbent Assay and invasion was analysed. The protective nature of the Aegle marmelos fruit lectin was assessed by analyzing apoptosis through dual staining method. Aegle marmelos fruit lectin significantly inhibited hemagglutination activity of Shigella and its minimum inhibitory concentration is 0.625 µg/well. Further, at this concentration lectin inhibited Shigella dysenteriae adherence and invasion of HT29 cells and protects the HT29 cells from Shigella dysenteriae induced apoptosis. To conclude, isolated lectin dimeric protein with N-acetylgalactosamine, Mannose and sialic acid binding specificity and inhibits adherence and invasion of Shigellae to HT29 cells thus, protects the host

Socioeconomic risk markers of arthropod-borne virus (arbovirus) infections: a systematic literature review and meta-analysis.

INTRODUCTION: Arthropod-borne viruses (arboviruses) are of notable public health importance worldwide, owing to their potential to cause explosive outbreaks and induce debilitating and potentially life-threatening disease manifestations. This systematic review and meta-analysis aims to assess the relationship between markers of socioeconomic position (SEP) and infection due to arboviruses with mosquito vectors. METHODS: We conducted a systematic search on PubMed, Embase, and LILACS databases to identify studies published between 1980 and 2020 that measured the association of SEP markers with arbovirus infection. We included observational studies without geographic location or age restrictions. We excluded studies from grey literature, reviews and ecological studies. Study findings were extracted and summarised, and pooled estimates were obtained using random-effects meta-analyses. RESULTS: We identified 36 observational studies using data pertaining to 106 524 study participants in 23 geographic locations that empirically examined the relationship between socioeconomic factors and infections caused by seven arboviruses (dengue, chikungunya, Japanese encephalitis, Rift Valley fever, Sindbis, West Nile and Zika viruses). While results were varied, descriptive synthesis pointed to a higher risk of arbovirus infection associated with markers of lower SEP, including lower education, income poverty, low healthcare coverage, poor housing materials, interrupted water supply, marital status (married, divorced or widowed), non-white ethnicities and migration status. Pooled crude estimates indicated an increased risk of arboviral infection associated with lower education (risk ratio, RR 1.5 95% CI 1.3 to 1.9); I2=83.1%), interruption of water supply (RR 1.2; 95% CI 1.1 to 1.3; I2=0.0%) and having been married (RR 1.5 95% CI 1.1 to 2.1; I2=85.2%). CONCLUSION: Evidence from this systematic review suggests that lower SEP increases the risk of acquiring arboviral infection; however, there was large heterogeneity across studies. Further studies are required to delineate the relationship between specific individual, household and community-level SEP indicators and arbovirus infection risks to help inform targeted public health interventions. PROSPERO REGISTRATION NUMBER: CRD42019158572