Impression cytology changes and corneoconjunctival calcification in patients with chronic renal failure

OBJECTIVE: To evaluate the relationship between corneoconjunctival calcification and conjunctival squamous metaplasia in patients with chronic renal failure (CRP). STUDY DESIGN: We studied impression cytology in 45 CRF patients on regular hemodialysis and 30 age- and sex-matched controls. Specimens were obtainedfrom the temporal bulbar conjunctiva using cellulose acetate filter paper. The samples were fixed in a mixture of 70% ethyl alcohol, 37% formaldehyde and glacial acetic acid and then stained with a combination of periodic acid- Schiff and Gill's modified Papanicolaou stain and graded by a masked observer. Corneoconjunctival calcification was graded by the Porter-Crombie classification. RESULTS: Of 45 study patients, 4 (9%) disclosed grade 0, 23 (51%) grade 1, 14 (31%) grade 2 and 4 grade 3 (9%) impression cytology changes. There was a statistically significant difference between the patient and control groups (p < 0.001). Calcium deposits were more frequent and extensive in CRF patients than in controls (p = 0.01). There was no correlation between impression cytology and calcium deposit grades (p = 0.128). However the presence of conjunctival inflammation correlated with the existence of extensive squamous metaplasia (p < 0.001). CONCLUSION: The severity of conjunctival changes in CRF patients on regular hemodialysis are not related to calcium deposition but to acute conjunctival inflammation.     

Anthropometry of male and female children in Crèches in Turkey

This paper presents the results of an anthropometrical survey conducted on male and female children aged 3, 4 and 5 years in Turkey. A set of 18 body dimensions was taken from 154 males and 132 females. It is considered that the 18 parameters are necessary for the design of school furniture, fittings and equipment in order to minimize musculoskeletal, visual and circulatory problems resulting from badly designed elements. This study identified significant gender differences in a set of 18 anthropometrical measures in this subject group.     

Achieving global equity for COVID-19 vaccines: Stronger international partnerships and greater advocacy and solidarity are needed

Peter Figueroa and co-authors advocate for equity in the worldwide provision of COVID-19 vaccines.

Many may not be aware of the full extent of global inequity in the rollout of Coronavirus Disease 2019 (COVID-19) vaccines in response to the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic. As of June 20, 2021, only 0.9% of those living in low-income countries and less than 10% of those in low- and middle-income countries (LMICs) had received at least 1 dose of a COVID-19 vaccine compared with 43% of the population living in high-income countries (HICs) [1] (Fig 1). Only 2.4% of the population of Africa had been vaccinated compared with 41% of North America and 38% of Europe [1,2] (S1 Fig). Primarily due to the inability to access COVID-19 vaccines, less than 10% of the population in as many as 85 LMICs had been vaccinated compared with over 60% of the population in 26 HICs [1]. Only 10 countries account for more than 75% of all COVID-19 vaccines administered [3]. This striking and ongoing inequity has occurred despite the explicit ethical principles affirming equity of access to COVID-19 vaccines articulated in WHO SAGE values framework [4,5] prepared in mid-2020, well prior to the availability of COVID-19 vaccines.Open in a separate windowFig 1Proportion of people vaccinated with at least 1 dose of COVID-19 vaccine by income (April 14 to June 23, 2021).Note: Data on China appeared on the database on June 9, hence the jump in upper middle-income countries. COVID-19, Coronavirus Disease 2019. Source: https://ourworldindata.org/covid-vaccinations.The COVID-19 pandemic highlights the grave inequity and inadequacy of the global preparedness and response to serious emerging infections. The establishment of the Coalition for Epidemic Preparedness Innovations (CEPI) in 2018, the Access to COVID-19 Tools Accelerator (ACT-A), and the COVID-19 Vaccines Global Access (COVAX) Facility in April 2020 and the rapid development of COVID-19 vaccines were all positive and extraordinary developments [6]. The COVAX Facility, as of June 2021, has delivered approximately 83 million vaccine doses to 75 countries, representing approximately 4% of the global supply, and one-fifth of this was for HICs [7]. The COVAX Facility has been challenged to meet its supply commitments to LMICs due to insufficient access to doses of COVID-19 vaccines with the prerequisite WHO emergency use listing (EUL) or, under exceptional circumstances, product approval by a stringent regulatory authority (SRA) [8,9]. Because of the anticipated insufficient COVID-19 vaccine supply through the COVAX Facility, the majority of nonvaccine-producing LMIC countries made the decision, early in the COVID-19 pandemic, to secure and use vaccines produced in China or Russia prior to receipt of WHO EUL or SRA approval. Most of the vaccines used in LMICs as of June 20, 2021 (nearly 1.5 billion doses of the 2.6 billion doses administered) were neither WHO EUL or SRA approved at the time they were given [10]. This may raise possible concerns with respect to the effectiveness, safety, and acceptability of individual vaccines used by many countries [8,9].     

Quantum-mechanical theory of CD for infinite helical polymers

Quantum-mechanical equations are derived that are particularly well suited to actual computations of the CD for helical polymers. They make use of cyclic boundary conditions and helical symmetry, so that only two matrices with a size equal to the number of transitions considered need be diagonalized. The final equations are expressed directly in terms of monomer properties and helical parameters to invite the same input as earlier calculations, and are given as a rotational strength times a shape function for ease of comparison with the earlier work. The shape of the helix term is expressed as a derivative with respect to ω and depends on the distance between monomers along the helix axis. Other terms involving two electric transition dipoles depend on the distance from the helix axis to the transition center. These equations are directly comparable to the classical equations derived for cyclic boundary conditions and helical symmetry. We present an outline of the derivation and enough intermediate steps to clarify how the equations arise.     

Determination of the effects on learning and memory performance and related gene expressions of clothianidin in rat models

Clothianidin (CLO) is one of the pesticides used to protect against insects, and its potential toxic effects on cognitive functions are not clearly known. This study aims to evaluate the possible effects of dose-dependent CLO on learning and memory in infant and adult male rats and the expression of related genes in the hippocampus. Doses of 2, 8 and 24 mg/kg of CLO were administered to newborn infant and adult albino Winstar rats in the form of gavage and dissolved in vehicle matter. Their cognitive and learning functions were evaluated by the Morris water maze and probe tests. Expression levels of N-methyl D-aspartate 1 (GRIN1), muscuranic receptor M1, synoptophysin (SYP) and growth-associated protein 43 (GAP-43) of tissues isolated from the hippocampus were determined using the real-time PCR method. In the Morris water maze test, no change (p > 0.05) was exhibited in the adult and infant rats after CLO was applied, although there was a significant difference (p < 0.05) in performance between infants and the control group after 24 mg/kg was applied in the probe test. Also, expression levels GRIN1, M1, SYP, GAP-43 did not change when compared to the control (p > 0.05). Our study shows that exposure to high doses of CLO causes deterioration of cognitive functions in infant rats.     

The Effects of Leptin on Rat Brain Development; An Experimental Study

International Journal of Peptide Research and Therapeutics -