Genotoxicity testing of chromium trioxide - a study using Vicia bioassay

In the present study by employing highly sensitive and simple plant bioassay, Vicia faba cytogenetic test, genotoxic property of chromium trioxide (CrO3) was evaluated. Roots of Vicia faba were treated with 10, 20. 30, 40 and 50 mg/l of CrO3 at room temperature in dark. The dosages selected for evaluation were below LD50 dose of the compound. Cytotoxicity and chromotoxicity were expressed in terms of depression in mitotic activity and frequency of chromosomal aberrations in mitotic phases. Treatment of roots caused dose and period of treatment related inhibition of mitotic activity.  Dose related increase in the frequencies of cells with chromosomal aberration in metaphase and anaphase stages were observed. Statistical analysis revealed significant effects of dose and periods of treatment. The results indicate genotoxic potential of chromium trioxide in the dose range tested

Changing Roles of Title I Reading Teachers in Light of New Provisions and Teamteaching Model

We present the important and very complicated roles of the Title I Reading teacher in light of a new instructional paradigm: teamteaching. Following the 1994 reauthorization of Title I, Reading teachers often find themselves in multiple professional roles (Improving America\u27s Schools Act, 1994). Based on observational data collected in our research on elementary school communities, five major categories of professional roles emerged (Oboler, 1993; Gupta and Oboler, 1998). We interpret Reading teachers\u27 roles with respect to the new provisions found in the Interim Report, 1996, issued by the U.S. Department of Education (http://www.ed.gov/pubs/NatAssess), and Title I, Part A, Title I of The Educational Excellence for All Children Act of 1999 (http://www.ed.gov/offices/oese/esea). Various dependent roles; such as, resource teacher, mentor, intern, team teacher, and administrator are subsumed under the title, Reading Teacher / Literacy Specialist. A teamteaching model for instructing students at-risk, in compliance with federal regulations, demonstrates successful collaborative teaching practices to maximize student learning opportunities

Emerging Theoretical Models of Reading through Authentic Assessments among Preservice Teachers: Two Case Studies

This two-part study examines the emerging understanding of the reading process among preservice teachers (PTs), enrolled in a teacher preparation course on diagnostic reading. The study focuses on the use of reading assessment tools to understand the process of reading, while using reading inventories for diagnostic as well as pedagogical purposes\u27 PTs\u27 self-reflections support a developing insight into the reading process. Through the process of inquiry and self-reflections, PTs discovered critical issues related to literacy, namely, metacognition, prior knowledge, cultural factors, instructional implications, and content area reading. These findings have implications for the teaching of reading as inquiry-based instruction, enabling teacher candidates to build their understanding of the reading process through an emerging personal model

Case report: Sleep deprivation presenting as acute psychosis

Sleeping is a basic human need and plays a key role in good health and well-being. Sleep deficiency can lead to physical and mental health problems, injuries, loss of productivity, and even a greater risk of death. Sleep deprivation is seen in several psychiatric disorders, and there may be a cause or effect relationship. Sleep-deprived individuals may have trouble making decisions, solving problems, controlling their emotions and behavior, and coping with stress or change. We report a case who started having sleep deprivation over 15 days following a stressor, which resulted in an acute psychosis-like condition with associated disorientation and perplexity. However, the patient responded to benzodiazepine medication given for the restoration of her sleep cycle and did not require any antipsychotics. There was also complete amelioration of her behavioral and thought disturbances

Effect of blood storage on electrolyte levels

Background: Blood transfusion can be an immediate life saving measure in several acute conditions such as hemorrhage and anemia. However, various post transfusion complications are observed in patients which may be associated with the storage conditions of the collected blood. Electrolytes play a major role in maintaining homeostasis within the cells. Potassium is the most important extracellular cation responsible for maintenance of the cell integrity. Prolonged and improper storage of blood can lead to leakage of electrolytes, thus changing the cell morphology. This can adversely affect the patients who receive such blood. This study helps us analyze the effect of blood storage on electrolyte levels.Methods: For the study, 10ml of blood was collected from 30 blood bags containing CPDA-1 at the time of blood donation from 30 different volunteers. This blood containing the CPDA-1 was divided into 5 parts of 2ml and each 2ml sample was stored in plain bulbs. All the samples were stored at 4°C. Samples were tested to check for changes in the electrolyte (Na+, K+, Cl-) levels on day 0, 3, 7, 14 and 21. ANOVA was used to calculate the variance in the electrolyte levels.Results: Average sodium level on day 0 was 152.9±3.8 mEq/l. There was a significant decrease and it was measured at 139.5±4.8 mEq/l on day 21. Average potassium level on day 0 was 4.2±0.4 mEq/l. A significant spike was observed in potassium levels. The final reading of potassium level on day 21 was 15.2±0.7 mEq/l. Average chloride level on day 0 was 71.9±6.6 mEq/l which significantly declined to 67±5.9 mEq/l.Conclusions: Though blood is stored in proper conditions, a biochemical change occurs within the cells due to prolonged storage and thus affects its viability

Delicate f(R) gravity models with disappearing cosmological constant and observational constraints on the model parameters

We study the $f(R)$ theory of gravity using metric approach. In particular we investigate the recently proposed model by Hu-Sawicki, Appleby $-$ Battye and Starobinsky. In this model, the cosmological constant is zero in flat space time. The model passes both the Solar system and the laboratory tests. But the model parameters need to be fine tuned to avoid the finite time singularity recently pointed in the literature. We check the concordance of this model with the $H(z)$ and baryon acoustic oscillation data. We find that the model resembles the $\Lambda$CDM at high redshift. However, for some parameter values there are variations in the expansion history of the universe at low redshift.Comment: 16 pages and 9 figures, typos corrected, few references and minor clarifications added, revised version to appera in PR

Chronic opioid pretreatment potentiates the sensitization of fear learning by trauma.

Despite the large comorbidity between PTSD and opioid use disorders, as well as the common treatment of physical injuries resulting from trauma with opioids, the ability of opioid treatments to subsequently modify PTSD-related behavior has not been well studied. Using the stress-enhanced fear learning (SEFL) model for PTSD, we characterized the impact of chronic opioid regimens on the sensitization of fear learning seen following traumatic stress in mice. We demonstrate for the first time that chronic opioid pretreatment is able to robustly augment associative fear learning. Highlighting aversive learning as the cognitive process mediating this behavioral outcome, these changes were observed after a considerable period of drug cessation, generalized to learning about multiple aversive stimuli, were not due to changes in stimulus sensitivity or basal anxiety, and correlated with a marker of synaptic plasticity within the basolateral amygdala. Additionally, these changes were not observed when opioids were given after the traumatic event. Moreover, we found that neither reducing the frequency of opioid administration nor bidirectional manipulation of acute withdrawal impacted the subsequent enhancement in fear learning seen. Given the fundamental role of associative fear learning in the generation and progression of PTSD, these findings are of direct translational relevance to the comorbidity between opioid dependence and PTSD, and they are also pertinent to the use of opioids for treating pain resulting from traumas involving physical injuries