High-Sensitivity Fluorescent Sensing Platform for Rapid and Selective Detection of Chlorpyrifos Pesticide in Water Samples Using Terbium-Isatin-3-allyl Complex.

The detection of organophosphorus pesticides, particularly chlorpyrifos, in environmental samples is essential due to their widespread use and associated health risks. In this study, we developed a high-sensitivity fluorescent sensing platform utilizing an Isatin-3-allyl-terbium (IS-Tb) complex in solution for the rapid and selective detection of chlorpyrifos in various water samples. The proposed chemical structure of the complex in solution was evaluated using molar ratio method.

Uncovering an effecient binary system as a chemosensor for visual and fluorescence detection of chromium (VI) in water samples.

There is an urgent requirement for the development of sensitive and quick sensors to monitor chromium (VI) due to its substantial carcinogenic and mutagenic properties. A coexisting system of coumarin 334 and diphenylcarbazide (C334/DPC) was used in this study as a fluorescent chemosensor to detect Cr(VI) ions. Upon the addition of Cr(VI), a purple chelate complex (Cr(III)-diphenylcarbazone) was produced, which resulted from the quantitative reaction between Cr(VI) ions and diphenylcarbazide (DPC), whereas no interaction between Cr(VI) and coumarin 334 took place.

Luminescent and time-resolved determination of gemifloxacin mesylate in pharmaceutical formulations and spiked blood plasma samples using a lanthanide complex as a probe.

A novel luminescence-based analytical methodology was established employing a europium(III) complex with 3-allyl-2-hydroxybenzohydrazide (HAZ) as the coordinating ligand for the quantification of gemifloxacin mesylate (GMF) in pharmaceutical preparations and human plasma samples spiked with the compound. The stoichiometry of the europium complex with HAZ was determined the Job plot and exhibited a metal-to-ligand ratio of 1 : 2. The analytical procedure relies on a rapid and significant enhancement of luminescence by the Eu(AZ) complex when it interacts with gemifloxacin mesylate, which allowed for the rapid detection of 96 samples within approximately 2 minutes.

Development of an optical sensor for the determination of phenolic compounds in environmental samples.

A new optical sensor was developed for the rapid sensing of total phenolic content, which is simple, cheap, and sensitive, using the Eu(III)-(NTA)-(Phen) complex [NTA = 1-(2-naphthoyl)-3,3,3-trifluoroacetone and Phen = 1,10 phenanthroline] as a luminescent probe at pH 7.5 using PIPES buffer. This method was based on luminescence quenching.

Sensitive ratiometric sensor for Al(III) detection in water samples using luminescence or eye-vision.

A facile, quick, and sensitive ratiometric luminescence sensor is designed for detection aluminum ions in water samples using luminescence or eye-vision. This approach relies on the emission change of the europium(III) complex with 3-(2-naphthoyl)-1,1,1,-trifluoro acetone (3-NTA) after interaction with various concentration of aluminum ions. The addition of aluminum ions suppressed the Eu(III) emission at 615 nm under 333 nm excitation, while simultaneously enhancing the ligand emission at 480 nm.

Fluorescence determination of Fe(iii) in drinking water using a new fluorescence chemosensor.

A new fluorescence chemosensor based on ()-2-(1-(3-oxo-3-benzo[]chromen-2-yl)ethylidene)hydrazine-1-carbothioamide (CEHC) has been developed for the determination of Fe(iii) in drinking water. The optimum conditions were acetate buffer solution with a pH 5.0.

Nanoparticles as a novel and promising antiviral platform in veterinary medicine.

Traditional veterinary virus vaccines, such as inactivated and live-attenuated vaccines, have achieved tremendous success in controlling many viral diseases of livestock and chickens worldwide. However, many recent viral outbreaks caused by different emerging and re-emerging viruses continue to be reported annually worldwide. It is therefore necessary to develop new control regimens.

Comparative effect of administration and discontinuation of sildenafil and/or clomipramine on the hepatic, cardiac and testicular tissues of male rats.

In this study, we examined the adverse consequences of prolonged treatment with sildenafil and/or clomipramine (CLO) on the hepatic, cardiac and testicular tissues of rats. Additionally, we investigated the potential effects of treatment discontinuation. To this end, 60 adult male rats were randomly assigned into six groups and were orally treated with 4.

Quercetin Reverses Altered Energy Metabolism in the Heart of Rats Receiving Adriamycin Chemotherapy.

The primary aim of this study was to find the potential modulatory roles of quercetin (QUE) against Adriamycin (ADR)-induced cardiotoxicity. A total of 50 rats were assigned to five groups: a control group, an ADR-treated group, a QUE-treated group, a prophylaxis-cotreated group, and a therapeutic-cotreated group, respectively. QUE exhibited a significant cardioprotective effect, particularly, when it was administered prior to and concurrently with ADR treatment (prophylaxis-cotreated group).

Exam anxiety in the undergraduate medical students of Taibah University.

Background And Objectives: Assessment is perceived to create highly stressful environment among medical students. Several studies have reported exam-related anxiety symptoms but the contributing factors seem to differ across institutions. This study aimed to determine the prevalence of exam anxiety, gender differences and the variables that moderate exam anxiety among students of a Saudi medical school.

Validation of a Fluorescence Sensor Microtiterplate for Biogenic Amines in Meat and Cheese.

An optical sensor microtiterplate for quantitative analysis of the total content of biogenic amines (TAC) in meat and cheese was developed and validated for the first time. In the plate, a chameleon dye (Py-1) is embedded in a polymeric cocktail which is deposited on the bottom of the wells in a common microtiterplate. On reaction with biogenic amines (BAs), the fluorescence of Py-1 at 620 nm rapidly delivers a precise TAC.

Fluorescence sensing of phosdrin pesticide by the luminescent Eu(III)- and Tb(III)-bis(coumarin-3-carboxylic acid) probes.

Luminescence quenching of the Eu(III)- and Tb(III)-bis (coumarin-3-carboxylic acid) (Ln(III)-(CCA)2) probes has been studied in the presence of organophosphorus or organochlorine pesticides; Phosdrin (P1), Malathion (P2), Profenofos (P3), Formothion (P4), Heptachlor (P5), and Endosulfan (P6). The luminescence intensity of lanthanide complex probes Ln(III)-(CCA)2 decreases as the concentration of the Phosdrin pesticide increases, while the other investigated pesticides have no significant influence on the lanthanide fluorescent intensities. It is observed that the quenching of Eu(III) and Tb(III)-coumarin-3-carboxylic acid by Phosdrin proceeds via static quenching processes according to Stern-Volmer plot.

Time-resolved fluorescence sensing of pesticides chlorpyrifos, crotoxyphos and endosulfan by the luminescent Eu(III)-8-allyl-3-carboxycoumarin probe.

This work describes the application of time resolved fluorescence in microtiter plates for investigating the interactions of europium-allyl-3-carboxycoumarin with pesticides chlorpyrifos, endosulfan and crotoxyphos. Stern-Volmer studies at different temperatures for chlorpyrifos and crotoxyphos shows dynamic and static quenching mechanisms respectively. Direct methods for the determination of the pesticides under investigation have been developed using the luminescence variations of the probe in solution.

Stapled hemorrhoidectomy; results of a prospective clinical trial in saudi arabia.

Objectives: This study was designed to evaluate the effectiveness of stapled hemorrhoidectomy (SH) in terms of cure of the symptoms and post-operative pain control.

Material And Methods: In this prospective clinical study, SH (Ethicon Endo-surgery, Cincinnati, OH) was performed for all patients with grade III and grade IV hemorrhoids, presenting to the surgical clinics of Ohud and Meeqat Hospitals Almadinah Almunawwarah Saudi Arabia. The results of SH were evaluated by a questionnaire focusing on the relief of symptoms, severity of post operative pain, and complications of SH.

Surgical management of retrosternal goiter: Local experience at a university hospital.

Background And Objective: Retrosternal goiter (RSG) is a term that has been used to describe a goiter that extends beyond the thoracic inlet. Surgery plays an important role in the treatment of these patients, but whether all or selected patients with RSG should undergo this operation remains controversial. Our aim is to look into the demographics, presentation, and treatment of patients with RSG and essentially to determine the role of surgery in its treatment.

High-throughput sensing microtiter plate for determination of biogenic amines in seafood using fluorescence or eye-vision.

A new optical sensing microplate was developed for rapid screening for the presence of biogenic amines (BAs) in seafood samples with high sensitivity. The deposition of a sensing spot (containing a chameleon dye (Py-1) in a polymeric cocktail) on the bottom of the wells of a standard microplate renders the plate a new sensing tool for a rapid and parallel detection of up to 96 (real) samples. This sensing microplate enables (1) a semi-quantitative readout of analyte concentration by eye-vision, (2) a rapid fluorescence readout of 96 samples with standard instrumentation in less than two minutes (unlike chromatographic and electrophoretic methods), (3) a statistically robust data evaluation (with 8-12 replicates) and (4) a rapid parallel sample preparation with standard 8 or 12-channel micropipettes.

Incidental parathyroidectomy during thyroid resection: incidence, risk factors, and outcome.

Background And Objectives: Thyroidectomy is a commonly performed procedure for thyroid problems. Inadvertent removal of the parathyroid glands is one of its recognized complications, which occurs more frequently in certain high-risk patients. The aim of this study was to identify the incidence, risk factors, and clinical relevance of incidental parathyroidectomy during thyroid surgery.

Improvement of psychometric properties of the objective structured clinical examination when assessing problem solving skills of surgical clerkship.

Objective: To improve the psychometric properties of the objective structured clinical examination (OSCE) and elevate staff motivation.

Methods: The OSCE was conducted in May 2006 at the Department of Surgery, King Saud University, Riyadh, Saudi Arabia as a pilot study for 95 students split over 2 consecutive days lasting 120 minutes each day. There were 15 actual stations on each day consisting of 10 stations that addressed problem solving skills, and 5 addressed clinical skills testing.

Effect of fluid preloading on postoperative nausea and vomiting following laparoscopic cholecystectomy.

Background: Postoperative nausea and vomiting (PONV) is a common complication following general anesthesia. Different regimens have been described for the treatment of PONV with few that mention the prevention of it. Therefore, we conducted this study to compare the effect of preloading with either crystalloids or colloids on the incidence of PONV following laparoscopic cholecystectomy (LC), under general anesthesia.

Haemostatic changes in laparoscopic cholecystectomy: a comparison between upper and lower limb measurements.

Background: The use of pnuemoperitonium to create the working environment for laproscopic cholecystectomy results in an increase in intraabdominal pressure, which exceeds the pressure of the venous-return from the legs. The resulting venous stasis may increase the risk of thrombosis formation and deep vein thrombosis in the lower limbs. However, there is no information as to whether the venous stasis will also exacerbate the coagulabililty of blood flowing out of the lower limbs.

Synthesis and fluorescence properties of Eu-anthracene-9-carboxylic acid towards N-acetyl amino acids and nucleotides in different solvents.

Europium (III) complex with anthracene-9-carboxylic acid (9-AA) has been synthesized and characterized by elemental analysis, FT-IR, and TG-DTG techniques. The results indicated that the composition of this complex is Eu (9-AA)(3). The luminescence properties of the complex in different solvents and at different pH values have been investigated.

Acute appendicitis: is removal of a normal appendix still existing and can we reduce its rate?

Background/aim: To determine the incidence of negative appendectomies and to identify factors that may reduce the risk of having the normal appendices removed surgically.

Design: Cross-sectional study.

Setting: College of Medicine and King Khalid University Hospital, Riyadh, Saudi Arabia.

Surgical residency training program. Are changes needed?

Objective: To obtain a collective opinion of practicing surgeons on the current state of general surgical residency training.

Methods: A data collection sheet was completed by the practicing surgeons involved in the residency training in 5 cities in Saudi Arabia, from January 2004 to December 2005. The survey questions covered mainly 3 aspects of surgical education: problems within the current education system, how education should be conducted, and the best approaches to correct education deficits.