Abstract Devices implanted into the body become encapsulated due to a foreign body reaction. In the central nervous system (CNS), this can lead to loss of functionality in electrodes used to treat ...disorders. Around CNS implants, glial cells are activated, undergo gliosis and ultimately encapsulate the electrodes. The primary cause of this reaction is unknown. Here we show that the mechanical mismatch between nervous tissue and electrodes activates glial cells. Both primary rat microglial cells and astrocytes responded to increasing the contact stiffness from physiological values ( G ′ ∼ 100 Pa) to shear moduli G ′ ≥ 10 kPa by changes in morphology and upregulation of inflammatory genes and proteins. Upon implantation of composite foreign bodies into rat brains, foreign body reactions were significantly enhanced around their stiff portions in vivo . Our results indicate that CNS glial cells respond to mechanical cues, and suggest that adapting the surface stiffness of neural implants to that of nervous tissue could minimize adverse reactions and improve biocompatibility.
Cataract is a common cause of avoidable blindness in children globally. Gender differences in service access among children are reported for several conditions, but not for surgery for bilateral ...cataract. In this review we compared the proportion of children undergoing surgery for bilateral, nontraumatic cataract who were girls, using data from high-income, gender-neutral countries as the reference.
Systematic review.
A systematic review of MEDLINE was undertaken in November 2014. Studies published only from 2000 onward were included because techniques and services have improved over time. A wide range of study designs was included such as: population-based data, registers, studies of surgical techniques, clinical trials, and so forth. All articles with 20 or fewer cases were excluded or were of long-term follow-up only, because this may reflect gender differences during follow-up. A meta-analysis was not planned.
Thirty-eight studies (6854 children) were included from 1342 titles, 10 from high-income countries. Many did not present data disaggregated by gender. Overall, 36.5% of children were girls. In gender-neutral countries, 47.5% of children (777/1636) were girls, being similar in the Middle East, North Africa, and Central Asia (48.6%; 87/179) and in Latin America and the Caribbean (43.7%; 188/430). Proportions were significantly lower in sub-Saharan Africa (41.1%; 225/547), East Asia and the Pacific (36.0%; 237/658), and South Asia (29.1%; 991/3404).
Access to surgery by girls with bilateral cataract is lower in some regions than by boys. Barriers to access specific to girls need to be identified, particularly in Asia, to assess interventions to improve uptake.
Cross-sectional blindness prevalence surveys are essential to plan and monitor eye care services. Incomplete or inaccurate reporting can prevent effective translation of research findings. The ...Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement is a 32 item checklist developed to improve reporting of observational studies. The aim of this study was to assess the completeness of reporting in blindness prevalence surveys in low and middle income countries (LMICs) using STROBE.
MEDLINE, EMBASE and Web of Science databases were searched on April 8 2016 to identify cross-sectional blindness prevalence surveys undertaken in LMICs and published after STROBE was published in December 2007. The STROBE tool was applied to all included studies, and each STROBE item was categorized as 'yes' (met criteria), 'no' (did not meet criteria) or 'not applicable'. The 'Completeness of reporting (COR) score' for each manuscript was calculated: COR score = yes / yes + no. In journals with included studies the instructions to authors and reviewers were checked for reference to STROBE.
The 89 included studies were undertaken in 32 countries and published in 37 journals. The mean COR score was 60.9% (95% confidence interval CI 58.1-63.7%; range 30.8-88.9%). The mean COR score did not differ between surveys published in journals with author instructions referring to STROBE (10/37 journals; 61.1%, 95%CI 56.4-65.8%) or in journals where STROBE was not mentioned (60.9%, 95%CI 57.4-64.3%; p = 0.93).
While reporting in blindness prevalence surveys is strong in some areas, others need improvement. We recommend that more journals adopt the STROBE checklist and ensure it is used by authors and reviewers.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To ascertain which countries in the world have retinopathy of prematurity (ROP) screening programmes and guidelines and how these were developed.
An email database was created and requests were sent ...to ophthalmologists in 141 nations to complete an online survey on ROP screening in their country.
Representatives from 92/141 (65%) countries responded. 78/92 (85%) have existing ROP screening programmes, and 68/78 (88%) have defined screening criteria. Some countries have limited screening and those areas which have no screening or for which there is inadequate knowledge are mainly Southeast Asia, Africa and some former Soviet states.
With the increasing survival of premature babies in lower-middle-income and low-income countries, it is important to ensure that adequate ROP screening and treatment is in place. This information will help organisations focus their resources on those areas most in need.
Oestrogens are pivotal in ovarian follicular growth, development and function, with fundamental roles in steroidogenesis, nurturing the oocyte and ovulation. Infections with bacteria such as ...Escherichia coli cause infertility in mammals at least in part by perturbing ovarian follicle function, characterised by suppression of oestradiol production. Ovarian follicle granulosa cells produce oestradiol by aromatisation of androstenedione from the theca cells, under the regulation of gonadotrophins such as FSH. Many of the effects of E. coli are mediated by its surface molecule lipopolysaccharide (LPS) binding to the Toll-like receptor-4 (TLR4), CD14, MD-2 receptor complex on immune cells, but immune cells are not present inside ovarian follicles. The present study tested the hypothesis that granulosa cells express the TLR4 complex and LPS directly perturbs their secretion of oestradiol. Granulosa cells from recruited or dominant follicles are exposed to LPS in vivo and when they were cultured in the absence of immune cell contamination in vitro they produced less oestradiol when challenged with LPS, although theca cell androstenedione production was unchanged. The suppression of oestradiol production by LPS was associated with down-regulation of transcripts for aromatase in granulosa cells, and did not affect cell survival. Furthermore, these cells expressed TLR4, CD14 and MD-2 transcripts throughout the key stages of follicle growth and development. It appears that granulosa cells have an immune capability to detect bacterial infection, which perturbs follicle steroidogenesis, and this is a likely mechanism by which ovarian follicle growth and function is perturbed during bacterial infection.
To explore the hypothesis that sight restoring cataract surgery provided to impoverished rural communities will improve not only visual acuity and vision-related quality of life (VRQoL) but also ...poverty and social status.
Participants were recruited at outreach camps in Tamil Nadu, South India, and underwent free routine manual small incision cataract surgery (SICS) with intra-ocular lens (IOL) implantation, and were followed up one year later. Poverty was measured as monthly household income, being engaged in income generating activities and number of working household members. Social status was measured as rates of re-marriage amongst widowed participants. VRQoL was measured using the IND-VFQ-33. Associations were explored using logistic regression (SPSS 19).
Of the 294 participants, mean age ± standard deviation (SD) 60 ± 8 years, 54% men, only 11% remained vision impaired at follow up (67% at baseline; p<0.001). At one year, more participants were engaged in income generating activities (44.7% to 77.7%; p<0.001) and the proportion of households with a monthly income <1000 Rps. decreased from 50.5% to 20.5% (p<0.05). Overall VRQoL improved (p<0.001). Participants who had successful cataract surgery were less likely to remain in the lower categories of monthly household income (OR 0.05-0.22; p<0.02) and more likely to be engaged in income earning activities one year after surgery (OR 3.28; p = 0.006). Participants widowed at baseline who had successful cataract surgery were less likely to remain widowed at one year (OR 0.02; p = 0.008).
These findings indicate the broad positive impact of sight restoring cataract surgery on the recipients' as well as their families' lives. Providing free high quality cataract surgery to marginalized rural communities will not only alleviate avoidable blindness but also - to some extent - poverty in the long run.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To evaluate the sensitivity and specificity of smartphone-based nonmydriatic (NM) retinal camera in the detection of diabetic retinopathy (DR) and sight-threatening DR (STDR) in a tertiary eye care ...facility.
Patients with diabetes underwent retinal photography with a smartphone-based NM fundus camera before mydriasis and standard 7-field fundus photography with a desktop mydriatic fundus camera after mydriasis. DR was graded using the international clinical classification of diabetic retinopathy system by two retinal expert ophthalmologists masked to each other and to the patient's identity. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) to detect DR and STDR by NM retinal imaging were assessed.
245 people had gradable images in one or both eyes. DR and STDR were detected in 45.3% and 24.5%, respectively using NM camera, and in 57.6% and 28.6%, respectively using mydriatic camera. The sensitivity and specificity to detect any DR by NM camera was 75.2% (95% confidence interval (CI) 68.1-82.3) and 95.2% (95%CI 91.1-99.3). For STDR the values were 82.9% (95% CI 74.0-91.7) and 98.9% (95% CI 97.3-100), respectively. The PPV to detect any DR was 95.5% (95% CI 89.8-98.5) and NPV was 73.9% (95% CI 66.4-81.3); PPV for STDR detection was 96.7% (95% CI 92.1-100)) and NPV was 93.5% (95% CI 90.0-97.1).
Smartphone-based NM retinal camera had fairly high sensitivity and specificity for detection of DR and STDR in this clinic-based study. Further studies are warranted in other settings.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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