Liquid crystal-assisted optical biosensor for early-stage diagnosis of mammary glands using HER-2

Breast cancer (BC) is one of the most commonly diagnosed cancers and the second leading cause of cancer mortality among women around the world. The purpose of this study is to present a non-labeled liquid crystal (LC) biosensor, based on the inherent feature of nematic LCs, for the evaluation of BC using the human epidermal growth factor receptor-2 (HER-2) biomarker. The mechanism of this sensing is supported by surface modification with dimethyloctadecyl [3-(trimethoxysilyl) propyl] ammonium chloride (DMOAP) encouraging the long alkyl chains that induce a homeotropic orientation of the LC molecules at the interface. To enhance the binding efficacy of more HER-2 antibody (Ab) on LC aligning agents, a simple ultraviolet radiation-assisted method was also used to increase functional groups on the DMOAP coated slides, thereby improving binding affinity and efficiency onto HER-2 Abs. The designed biosensor makes use of the specific binding of HER-2 protein to HER-2 Ab and disruption of the orientation of LCs. This orientation change leads to a transition of the optical appearance from dark to birefringent, enabling the detection of HER-2. This novel biosensor exhibits a linear optical response to HER-2 concentration in the wide dynamic range of 10^-6-10² ng/mL, with an ultra-low detection limit of 1 fg/mL. As a proof of concept, the designed LC biosensor was successfully investigated for the quantification of HER-2 protein in patients suffering from BC. Owing to the sensitivity, selectivity, and label-free detection, this biosensor may amplify the application of LC-based biosensors for the detection of most types of cancers.

On Natural History and Management of Colloid Cysts: Time to Rethink?

BACKGROUND

Colloid cysts, although benign, may occasionally cause obstructive hydrocephalus and sudden death. Reliable prognostic factors for symptomatic progression have been sought, with heterogenous results.

METHODS

We conducted a retrospective review of all cases of colloid cysts of the third ventricle managed at our center between 2009 and 2019. Clinical and neuroimaging characteristics were analyzed using logistic regression in relation to symptomatic status and hydrocephalus. The cutoff values for outcome prediction were calculated using the receiver operating characteristic curve analysis.

RESULTS

There were 82 patients with colloid cysts, of whom 60 were asymptomatic and 22 symptomatic. None of the asymptomatic patients experienced acute neurologic decline or hydrocephalus during follow-up, whereas half (n = 11) of the symptomatic patients presented with hydrocephalus, 8 of whom had acute hydrocephalus. We found 3 putative candidate risk factors for symptomatic colloid cysts: T1-weighted magnetic resonance imaging hyperintense/mixed signal appearance (P = 0.004), location in risk zone I (P = 0.007), and a volume >236.49 mm³ (P = 0.007). Cyst diameter and volume/foramen of Monro diameter ratios had a decreasing trend over time among asymptomatic patients, providing new insights into the natural history of the disease.

CONCLUSIONS

Only a few asymptomatic colloid cysts showed progression requiring surgery, with no acute deterioration or fatal events, whereas the rest remained stable over time, thus supporting a more conservative approach for this group of patients. Higher risk for developing symptomatic colloid cyst was defined by a risk score that included T1-weighted magnetic resonance imaging appearance, risk zone, and colloid cyst volume, aiding the detection of patients at risk of clinical deterioration.

Cognitive impairment in people with physical frailty using the phenotype model: A systematic review and meta analysis

OBJECTIVE

We performed a systematic review and meta-analysis to study the relationship between cognitive functioning and phenotypic frailty status.

METHODS

We searched Pubmed, Cochrane Library and Epistemonikos from 2000 until March 2022, and used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Samples included both sexes, age ≥55 years, assessed with standardized measures of the different cognitive domains and the frailty phenotype model and analyzing the relationship between the frailty subtypes pre-frail, frail and robust and specific cognitive function.

RESULTS

Eleven studies published from 2008 until March 2022 fulfilled the inclusion criteria, and 10 were included in our meta-analyses. Sample sizes varied from 104 to 4649 individuals. Mean Mini-Mental State Examination (MMSE) scores ranged from 17.0 to 27.6, with mean difference (MD) of -2.55 (95% confidence interval [CI] -3.32, -1.78) in frail compared to robust, MD -1.64 (95% CI -2.21, -1.06) in frail compared to prefrail and MD -0.68 (95% CI -0.94, -0.43) in prefrail compared to robust. In subgroup analyses, frail persons had lower scores in the memory domain with standardized mean difference (SMD) -1.01 (95% CI -1.42, -0.59).

CONCLUSION

MMSE scores were significantly lower in frail compared to robust and prefrail persons and in prefrail compared to robust persons. Subgroup analysis of memory revealed significantly poorer scores in frail compared to robust. The results indicate a strong relationship between physical frailty and cognitive impairment suggesting incorporation of cognitive function in frailty assessments.

COVID-19 leukoencephalopathy with subacute magnetic resonance imaging findings of vasculitis and demyelination

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) commonly results in a respiratory illness in symptomatic patients; however, those critically ill can develop a leukoencephalopathy. We describe two patients who had novel subacute MRI findings in the context of coronavirus disease 2019 (COVID-19) leukoencephalopathy, which we hypothesize could implicate a potent small-vessel vasculitis, ischemic demyelination and the presence of prolonged ischemia. Recent evidence of the direct neuroinvasiness of SARS-CoV-2 leading to ischemia and vascular damage supports this hypothesis.

Evaluation of cold-weather wastewater nitrification technology for removal of polar chemicals of emerging concern from rural Manitoba wastewaters

Aerated lagoons, typically used by small communities, often provide limited removal of wastewater nutrients. Given increasingly stringent wastewater standards, it is imperative that effective, but economical and easy-to-operate, treatment technologies be developed. The Submerged Attached Growth Reactor (SAGR®) is a treatment process developed to perform nitrification near freezing temperatures. Previous tests on full-scale installations have shown that SAGR could consistently remove ammonia to below current Canadian standards and provide additional total suspended solids and biochemical oxygen demand removal. In this study, we evaluated removal of polar chemicals of emerging concern (CECs), including pharmaceuticals, personal care products, and pesticides, at SAGR installations in two Manitoba First Nations communities (MCN and LPFN) under cold winter conditions. Both showed some removal of diclofenac, naproxen, clarithromycin, metoprolol, and trimethoprim, likely by biotransformation. Average naproxen removal was 21% (2.53 × 10³ ng L^-1) in MCN and 64% (1.58 × 10³ ng L^-1) in LPFN. Atenolol was well-removed by SAGR, by 80% on average (range of 64%-94%). Clarithromycin, metoprolol, and trimethoprim removal was similar within and between systems, ranging from 54% to 76% (30.8-3.07 × 10² ng L^-1 removed). Carbamazepine was detected in nearly all samples, but was not well-removed, consistent with other treatment studies. Overall, results showed that SAGR technology could moderately remove CECs, while providing the designed treatment performance for other parameters. This work will help to improve our understanding of wastewater treatment in small and/or remote communities with limited infrastructure and challenging cold-weather conditions.

Investigation of quadratic electro-optic effects and electro-absorption process in GaN/AlGaN spherical quantum dot

Quadratic electro-optic effects (QEOEs) and electro-absorption (EA) process in a GaN/AlGaN spherical quantum dot are theoretically investigated. It is found that the magnitude and resonant position of third-order nonlinear optical susceptibility depend on the nanostructure size and aluminum mole fraction. With increase of the well width and barrier potential, quadratic electro-optic effect and electro-absorption process nonlinear susceptibilities are decreased and blueshifted. The results show that the DC Kerr effect in this case is much larger than that in the bulk case. Finally, it is observed that QEOEs and EA susceptibilities decrease and broaden with the decrease of relaxation time.

Relationship between admission hypoalbuminemia and inhospital mortality in acute stroke

This study aims at assessing the relation between hypoalbuminemia and inhospital mortality in patients with acute stroke. In this cross-sectional study, a total of 112 consecutively admitted patients with first acute stroke in Ahvaz Jundishapur Hospital were enrolled. All patients hospitalized for 7-9 days or expired in this period of time. Admission hypoalbuminemia (serum albumin < 3.5 mg dL(-) as well as other prognostic factors were determined and compared between the two groups. One hundred and twelve patients, 74 males and 38 females with the mean age of 69.2 +/- 12.1 (66-79) years were enrolled. Twenty nine (25.9%) patients expired during the hospitalization. Totally, admission hypoal buminemia was present in 49 (43.8%) patients. 43% of the patients were Hypoalbuminemia. Frequency of patients with admission hypoalbuminemia and is chemic heart disease was significantly higher in the nonsurvivors (75.8-32.5%, p = 0.001; 34.5 vs. 16.9%, p = 0.047, respectively). The mean Glasgow Coma Scale score was significantly lower in the nonsurvivors (8.1 +/- 1.8 vs. 9.4 +/- 0.5, p = 0.003). These three parameters remained significant in multivariate analysis. Sex, age, history of hypertension, diabetes mellitus, hypertriglyceridemia, hypercholesterolemia, anemia, heart failure and smoking habit, admission atrial fibrillation, ethnicity and stroke type were comparable between the two groups. In conclusion, hypoalbuminemia is an independent predictor of inhospital mortality in patients with acute stroke.

[Differential diagnosis of retinoblastoma: a retrospective study of 486 cases]

OBJECTIVES

Detail the most frequent problems encountered in the differential diagnosis of retinoblastoma.

PATIENTS

and method: We conducted a retrospective study on the children referred to the Curie Institute for suspicion of retinoblastoma between 2000 and 2006. Diagnosis was made by fundus examination using the indirect ophthalmoscope, ultrasonography, and MRI.

RESULTS

Of the 486 children seen during this period, 408 had unilateral or bilateral retinoblastoma and 78 (16%) had another lesion: Coats disease (20 children, 25%), congenital malformations (23 children, 30%; coloboma, PHPV, microphthalmia, isolated or associated with retinal dysplasia), other tumors (10 children, 13%; astrocytomas and medulloepithelioma), combined hamartomas (six children, 8%), inflammatory diseases (six children, 8%) (Toxocara canis, cat scratch eye disease, or toxoplasmosis), and other diseases (13 children, 16%; corneal opacities, congenital cataract, or retinal detachment).

DISCUSSION

Compared to previous series, this study shows the proportion of erroneous diagnosis has lowered (16%) compared to earlier studies by Balmer (1986; 30%), and Shields (1991; 42%). No cases of retinopathy of prematurity were seen in our series, demonstrating that screening is good or of a lower frequency in France. The frequency of PHPV has dropped. Coats disease remains a frequent and sometimes difficult diagnosis to make, particularly in advanced stages of the disease.