Gelatin particle indirect agglutination and enzyme-linked immunosorbent assay for diagnosis of strongyloidiasis using Strongyloides venezuelensis antigen

Routine microscopical examination of stool specimens for diagnosis of strongyloidiasis is insensitive and serological methods using Strongyloides stercoralis antigen are at present not available for field studies. We evaluated 2 techniques, enzyme-linked immunosorbent assay (ELISA) and gelatin particle indirect agglutination (GPIA), using an antigen obtained from the rodent parasite, S. venezuelensis. Fifty-four Peruvian patients with different clinical forms of strongyloidiasis were studied: 12 asymptomatic, 31 symptomatic, and 11 hyperinfection cases. Our results demonstrate that both ELISA and GPIA using S. venezuelensis antigen are useful for diagnosis of strongyloidiasis, with sensitivities of 74.1% and 98.2%, respectively and a specificity of 100% for both techniques. We found that GPIA is a highly sensitive test for patients with suspected chronic infection and/or hyperinfection. In the hyperinfection cases, significantly lower concentrations of specific immunoglobulin antibodies and eosinophils (P < 0.001) were found compared with the asymptomatic and symptomatic cases.     

Sentinel Lymph Node Metastasis in Microinvasive Breast Cancer

Background:Ductal carcinoma in situ with microinvasion (DCISM) is a separate pathological entity, distinct from pure ductal carcinoma in situ (DCIS). DCISM is a true invasive breast carcinoma with a well-known metastatic potential. Currently, there is controversy regarding the indication for complete axillary dissection (CAD) to stage the axilla in patients with DCISM. The role of CAD is questioned given its morbidity and reported low incidence of axillary involvement. Sentinel lymph node biopsy (SLNB) may obviate the need for CAD in these patients without compromising the staging of the axilla and the important prognostic information.Methods:From March 1996 to December 2002, 4602 consecutive patients with invasive breast carcinoma underwent SLN biopsy. Of these, 41 patients with DCISM were selected.Results:Metastasis in the SLN were detected in 4 of 41 (9.7%) patients. Two of the 4 patients had only micrometastasis in the SLN. In three patients, the SLN was the only positive node after CAD.Conclusions:SLN biopsy should be considered as a standard procedure in DCISM patients. SLNB can detect nodal micrometastasis and accurately stage the axilla avoiding the morbidity of a CAD. Complete AD may not be mandatory if only the SLN contains micrometastatic disease. Informed consent is very important in the decision not to undergo CAD.     

Effects of chronic intraventricular infusion of heparin glycosaminoglycan on learning and brain acetylcholine parameters in aged rats

We reported previously that the glycosaminoglycan heparin (HP) has the facility to improve learning in adult rodents when administered into the nucleus basalis of the ventral pallidum. Here we gauged the effects of chronic intraventricular infusion of HP (20 ng per day over 28 days) in 26-month-old rats in terms of Morris water maze performance, habituation to a novel open field, retention of a step-through inhibitory avoidance task and changes in forebrain acetylcholine (ACh) levels. Control groups included vehicle-infused old and adult (3-month-old) rats. The chronic infusion of HP did not significantly influence the performance of the old animals in any of the learning and memory tasks employed. HP only slightly facilitated the retention of the inhibitory avoidance task and the rate of habituation in the open-field paradigm. In the water maze, the glycosaminoglycan did not counteract the navigation deficits observed for aged controls and even impaired performance during the initial place-learning trials. After behavioural testing, tissue levels of ACh were determined in frontal cortex, ventral striatum, neostriatum and hippocampus without detecting any obvious neurochemical differences between groups. The current results, together with our previous work, indicate that HP differentially affects learning and memory parameters in adult and aged rats. Thus, whereas the glycosaminoglycan proved effective in facilitating mnemonic functions in normal adult animals, no such a clear-cut beneficial effect was observed in behaviourally impaired old rats.     

Arterial narrowing as a predictive factor in glaucoma

Purpose: To evaluate whether retinal arteriolar widths change in normal patients and in different glaucoma types. We measured the arteriolar width at the merge in the optic nerve (MD), at the edge of the optic nerve (ED) and at the peripapillary area (1 disc diameter distance) (disc distance D). HRT software 1.11, Interactive Means program was used.One hundred forty three eyes of seventy-two patients divided in four subgroups normal, low-tension glaucoma (LTG), primary open angle glaucoma (POAG) and ocular hypertensive (OH). No statistically significant was found in each studied group. The normal patients showed no changes in the retinal arteriolar width compared with all the glaucoma groups.     

Urban air pollution: Influences on olfactory function and pathology in exposed children and young adults

Mexico City (MC) residents are exposed to severe air pollution and exhibit olfactory bulb inflammation. We compared the olfactory function of individuals living under conditions of extreme air pollution to that of controls from a relatively clean environment and explore associations between olfaction scores, apolipoprotein E (APOE) status, and pollution exposure. The olfactory bulbs (OBs) of 35 MC and 9 controls 20.8±8.5 years were assessed by light and electron microscopy. The University of Pennsylvania Smell Identification Test (UPSIT) was administered to 62 MC/25 controls 21.2±2.7 years. MC subjects had significantly lower UPSIT scores: 34.24±0.42 versus controls 35.76±0.40, p=0.03. Olfaction deficits were present in 35.5% MC and 12% of controls. MC APOE ε 4 carriers failed 2.4±0.54 items in the 10-item smell identification scale from the UPSIT related to Alzheimer's disease, while APOE 2/3 and 3/3 subjects failed 1.36±0.16 items, p=0.01. MC residents exhibited OB endothelial hyperplasia, neuronal accumulation of particles (2/35), and immunoreactivity to beta amyloid βA₄₂ (29/35) and/or α-synuclein (4/35) in neurons, glial cells and/or blood vessels. Ultrafine particles were present in OBs endothelial cytoplasm and basement membranes. Control OBs were unremarkable. Air pollution exposure is associated with olfactory dysfunction and OB pathology, APOE 4 may confer greater susceptibility to such abnormalities, and ultrafine particles could play a key role in the OB pathology. This study contributes to our understanding of the influences of air pollution on olfaction and its potential contribution to neurodegeneration.     

Evaluation of common genetic variants in 82 candidate genes as risk factors for neural tube defects

ABSTRACT: BACKGROUND: Neural tube defects (NTDs) are common birth defects (~1 in 1000 pregnancies in the US and Europe) that have complex origins, including environmental and genetic factors. A low level of maternal folate is one well-established risk factor, with maternal periconceptional folic acid supplementation reducing the occurrence of NTD pregnancies by 50-70%. Gene variants in the folate metabolic pathway (e.g., MTHFR rs1801133 (677 C > T) and MTHFD1 rs2236225 (R653Q)) have been found to increase NTD risk. We hypothesized that variants in additional folate/B12 pathway genes contribute to NTD risk. METHODS: A tagSNP approach was used to screen common variation in 82 candidate genes selected from the folate/B12 pathway and NTD mouse models. We initially genotyped polymorphisms in 320 Irish triads (NTD cases and their parents), including 301 cases and 341 Irish controls to perform case-control and family based association tests. Significantly associated polymorphisms were genotyped in a secondary set of 250 families that included 229 cases and 658 controls. The combined results for 1441 SNPs were used in a joint analysis to test for case and maternal effects. RESULTS: Nearly 70 SNPs in 30 genes were found to be associated with NTDs at the p < 0.01 level. The ten strongest association signals (p-value range: 0.0003-0.0023) were found in nine genes (MFTC, CDKN2A, ADA, PEMT, CUBN, GART, DNMT3A, MTHFD1 and T (Brachyury)) and included the known NTD risk factor MTHFD1 R653Q (rs2236225). The single strongest signal was observed in a new candidate, MFTC rs17803441 (OR = 1.61 [1.23-2.08], p = 0.0003 for the minor allele). Though nominally significant, these associations did not remain significant after correction for multiple hypothesis testing. CONCLUSIONS: To our knowledge, with respect to sample size and scope of evaluation of candidate polymorphisms, this is the largest NTD genetic association study reported to date. The scale of the study and the stringency of correction are likely to have contributed to real associations failing to survive correction. We have produced a ranked list of variants with the strongest association signals. Variants in the highest rank of associations are likely to include true associations and should be high priority candidates for further study of NTD risk.     

Teleophthalmology and the digital divide: inequities highlighted by the COVID-19 pandemic

The COVID-19 pandemic has brought an unprecedented change in the way we deliver eye care to our patients, most notably with the rapid addition of telehealth technology into our practices. We have welcomed telehealth with open arms in hopes that it would improve access to care for our patients; however, one question remains: Does it improve health equity?Subject terms: Public health, Risk factors     

Ophthalmic artery Doppler velocimetry in healthy pregnancy

OBJECTIVES: To establish normative data for ophthalmic artery Doppler parameters throughout a healthy pregnancy, to investigate the possible correlation between these Doppler measurements and gestational age, and to test intraobserver variability. METHODS: A prospective cross-sectional study was performed to assess various Doppler parameters in 276 healthy women between 20 and 39 weeks of gestation. The following measurements were obtained: pulsatility and resistance indices (PI, RI), peak systolic velocity (PSV), peak diastolic velocity (PDV), end diastolic flow velocity (EDFV), and peak ratio (PR). Quantile regression was used to estimate reference values throughout pregnancy and P<0.05 was considered significant. The intraclass correlation coefficient (Intra-CC) was used to calculate intraobserver variability. RESULTS: The 5th and 95th prediction intervals for each gestational age are presented. No significant correlation was detected between Doppler indices and gestational age. Intra-CC was excellent (0.996). CONCLUSIONS: Reference values were generated for ophthalmic artery Doppler measurements, and they did not vary significantly during healthy pregnancy.     

Motivational Interviewing enhances the adoption of water disinfection practices in Zambia

These studies represent the first adaptation of the MotivationalInterviewing (MI) behavior change approach in the developingworld, using health workers directly from the community. Theobjective was to compare the effectiveness of the standard practiceof health education (comparison group) to MI (experimental group)in initiating and sustaining safe water treatment and storagebehavior. Methods: focus groups and community surveys were conductedprior to health worker training. The main outcome variableswere detectable disinfectant levels in stored household water(for Field Trial 1) and disinfectant sales (for Field Trial2). Results: in Field Trial 1 (n = 185 households), a very highadherence rate was achieved (range 71.1–94.7%), with nostatistical differences between the groups. Field Trial 2 (n= 427 households) incorporated lessons learned from the previoustrial and resulted in much higher purchase rates of the disinfectantin the MI group, t(7) = 10.69, p < 0.001, eta² = 0.94. Conclusion:MI intervention appears promising for public health initiativesin the developing world. Further work in this area is indicated.