27 research outputs found
Hair follicles as a target structure for nanoparticles
For at least two decades, nanoparticles have been investigated for their
capability to deliver topically applied substances through the skin barrier.
Based on findings that nanoparticles are highly suitable for penetrating the
blood–brain barrier, their use for drug delivery through the skin has become a
topic of intense research. In spite of the research efforts by academia and
industry, a commercial product permitting the nanoparticle-assisted delivery
of topically applied drugs has not yet been developed. However, nanoparticles
of approximately 600 nm in diameter have been shown to penetrate efficiently
into the hair follicles, where they can be stored for several days. The
successful loading of nanoparticles with drugs and their triggered release
inside the hair follicle may present an ideal method for localized drug
delivery. Depending on the particle size, such a method would permit targeting
specific structures in the hair follicles such as stem cells or immune cells
or blood vessels found in the vicinity of the hair follicles
Elucidation of the MicroRNA Transcriptome in Western Corn Rootworm Reveals Its Dynamic and Evolutionary Complexity
Diabrotica virgifera virgifera (western corn rootworm, WCR) is one of the most destructive agricultural insect pests in North America. It is highly adaptive to environmental stimuli and crop protection technologies. However, little is known about the underlying genetic basis of WCR behavior and adaptation. More specifically, the involvement of small RNAs (sRNAs), especially microRNAs (miRNAs), a class of endogenous small non-coding RNAs that regulate various biological processes, has not been examined, and the datasets of putative sRNA sequences have not previously been generated for WCR. To achieve a comprehensive collection of sRNA transcriptomes in WCR, we constructed, sequenced, and analyzed sRNA libraries from different life stages of WCR and northern corn rootworm (NCR), and identified 101 conserved precursor miRNAs (pre-miRNAs) in WCR and other Arthropoda. We also identified 277 corn rootworm specific pre-miRNAs. Systematic analyses of sRNA populations in WCR revealed that its sRNA transcriptome, which includes PIWI-interacting RNAs (piRNAs) and miRNAs, undergoes a dynamic change throughout insect development. Phylogenetic analysis of miRNA datasets from model species reveals that a large pool of species-specific miRNAs exists in corn rootworm; these are potentially evolutionarily transient. Comparisons of WCR miRNA clusters to other insect species highlight conserved miRNA-regulated processes that are common to insects. Parallel Analysis of RNA Ends (PARE) also uncovered potential miRNA-guided cleavage sites in WCR. Overall, this study provides a new resource for studying the sRNA transcriptome and miRNA-mediated gene regulation in WCR and other Coleopteran insects
Educação científica na perspectiva de letramento como prática social: funções, princípios e desafios
Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study
Summary
Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally.
Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies
have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of
the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income
countries globally, and identified factors associated with mortality.
Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to
hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis,
exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a
minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical
status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary
intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause,
in-hospital mortality for all conditions combined and each condition individually, stratified by country income status.
We did a complete case analysis.
Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital
diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal
malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome
countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male.
Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3).
Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income
countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups).
Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome
countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries;
p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients
combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11],
p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20
[1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention
(ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety
checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed
(ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of
parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65
[0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality.
Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome,
middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will
be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger
than 5 years by 2030