Development and validation of stability-indicating high performance liquid chromatography method to analyze gatifloxacin in bulk drug and pharmaceutical preparations

Quantitative determination of gatifloxacin in tablets, solid lipid nanoparticles (SLNs) and eye-drops using a very simple and rapid chromatographic technique was validated and developed. Formulations were analyzed using a reverse phase SUPELCO® 516 C-18-DB, 50306-U, HPLC column (250 mm × 4.6 mm, 5 μm) and a mobile phase consisting of disodium hydrogen phosphate buffer:acetonitrile (75:25, v/v) and with orthophosphoric acid pH was adjusted to 3.3 The flow rate was 1.0 mL/min and analyte concentrations were measured using a UV-detector at 293 nm. The analyses were performed at room temperature (25 ± 2 °C). Gatifloxacin was separated in all the formulations within 2.767 min. There were linear calibration curves over a concentration range of 4.0–40 μg.mL⁻¹ and correlation coefficients of 0.9998 with an average recovery above 99.91%. Detection of analyte from different dosage forms at the same R_t indicates the specificity and stability of the developed method.     

COVID-19 impact on pharmacy education in Saudi Arabia: Challenges and opportunities

The first case of COVID-19 was announced at the end of year 2019, and later many cases were identified worldwide. In Saudi Arabia, the first case was announced on 2 March 2020. To prevent the spread of this pandemic disease, many precautionary actions were taken by Saudi government. One of these actions was closing public and private schools and universities and transfer the educational activities to virtual platforms. All colleges of Pharmacy in Saudi Arabia, whether the 21 public or the eight private ones, were affected by those sudden transitions and their responses varied according to their preparedness levels. Here we shared our experience in king Saud University in the curricular components of pharmacy school that includes classroom teaching, laboratory teaching, experiential training, assessment, and extracurricular activity and student support during COVID-19 compulsory lockdown. Lastly, we presented the lesson learned toward pharmacy education from COVID-19 pandemic.     

Two decades of the synthesis of mono- and bis-aminomercapto[1,2,4]triazoles

4-Amino-5-mercapto[1,2,4]triazole and its 3-substituted derivatives have proven to be of biological interest and provide access to a new class of biologically active heterocyclic compounds for biomedical applications. This study will be helpful for scientific researchers interested in the chemistry of bifunctional versatile compounds as it provides a collection of all the methods for the preparation of 3-substituted-4-amino-5-mercapto[1,2,4]triazoles with aliphatic, aromatic, and heterocyclic moieties during the period from 2000 to mid-2020.

4-Amino-5-mercapto[1,2,4]triazole and its 3-substituted derivatives have proven to be of biological interest and provide access to a new class of biologically active heterocyclic compounds for biomedical applications.     

STAT3-siRNA induced B16.F10 melanoma cell death: more association with VEGF downregulation than p-STAT3 knockdown

STAT3 knockdown by small interfering RNA (siRNA) has been described to inhibit carcinogenic growth in various types of tumors. Earlier we have reported delivery of siRNA by oleic acid- and stearic acid-modified-polyethylenimine and enhancement of silencing of STAT3 by small interfering RNA (siRNA) in B16.F10 melanoma cell lines and consequent tumor suppression. Present investigation mainly focused on the downstream events involved in B16.F10 melanoma cell death and consequent tumor suppression following knockdown of p-STAT3 by siRNA. Lipid-substituted polyethylenimine (PEI)-p-STAT3-siRNA were prepared and characterized by measuring its N/P ratio, zeta potential, size, association and dissociation with siRNA. B16.F10 melanoma cells were treated with six different concentrations of PEI-p-STAT3-siRNA (200, 100, 50, 25, 12.5 and 6.25?nM). Downregulation of p-STAT3 and VEGF were studied using western blot and ELISA in association with the melanoma cell death. PEI-p-STAT3-siRNA hydrodynamic diameter ranged from 110 to 270?nm. PEI assisted p-STAT3-siRNA delivery exhibited increased uptake by B16.F10, when analyzed by fluorescent and confocal microscopy along with flowcytometry. It induced concentration-dependent knockdown of the p-STAT3 that also downregulated VEGF expression in similar fashion and induced B16.F10 cell death. Higher concentrations of p-STAT3-siRNA appear to significantly downregulate the VEGF expression via p-STAT3 knockdown. Decreasing survival of B16.F10 cells with the increasing concentration of p-STAT3-siRNA significantly correlated with VEGF downregulation, not with p-STAT3 expression. Data suggest that VEGF downregulation following knockdown of p-STAT3 may be a key event in survival reduction in B16.F10 melanoma cells and.     

Coagulation parameters of captive mountain gazelle (Gazella gazella Pallas, 1766; Bovidae: Antilopinae) and Nubian ibex (Capra ibex nubiana Cuvier, 1825; Bovidae: Caprinae)

The coagulation profiles of 36 mountain gazelles (Gazella gazella) aged 2–6?years, and 17 Nubian ibexes (Capra ibex nubiana), aged 1–4?years, were evaluated and compared. The following parameters were determined in both species: prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen concentration (FIB), and clotting factors VII, VIII:C, IX, X, and XI. Thrombin clotting time (TCT) was also determined in mountain gazelles. The results indicated significant interspecies differences in most parameters, with lower PT, aPTT, and factors VII, IX, and XI and higher factor XIII:C activities in the Nubian ibex than the mountain gazelle. Gender seemed to have a limited influence on these parameters within each species. Both species had higher plasma FIB and factor VIII:C activity relative to humans. This study is the first record of coagulation variables in these two species of wild Arabian desert ruminants.     

Displaced plaque in retroperitoneal adenopathy

BACKGROUND: This study was designed to determine when to consider incidental retroperitoneal masses on the basis of a displaced calcified atheromatous abdominal aorta on lateral radiographs. METHODS: We did a retrospective review of 143 normal abdominal helical computed tomography scans of individuals aged 50 years and older to measure the distance between the posterior aortic wall and anterior cortex of vertebral bodies from T12 through L3. RESULTS: The normal abdominal aorta maintains a close relationship to the vertebral column. The distance should not be more than 10 mm in men and 7.3 mm in women. CONCLUSION: Displacement of aortic calcified atheroma greater than these distances should prompt a search for a retroperitoneal mass.     

Delayed diagnosis of systemic lupus erythematosus due to lack of competency skills in musculoskeletal examination

Deficiencies in musculoskeletal (MSK) examination skills among internal medicine residents can cause serious outcomes. We report a case of systemic lupus erythematosus with active arthritis where the diagnosis was delayed for 7 days after hospital admission due to the lack of basic skills in MSK examination.     

Discrimination of capsular stage brain abscesses from necrotic or cystic neoplasms using diffusion-weighted magnetic resonance imaging

OBJECT: The authors' aim was to assess the ability of apparent diffusion coefficient (ADC) ratios in distinguishing brain abscesses from cystic or necrotic neoplasms. METHODS: Fifty-three patients with rim-enhancing masses in the brain observed on T1-weighted MR images were included: 26 had abscesses (14 bacterial, six nonbacterial, and six of unknown origin), 11 had glioblastoma multiforme, and 16 had rim-enhancing metastasis. The ADC values, derived from diffusion-weighted imaging, were measured in the most homogeneous portion of the cystic component of the mass. The ADC ratios were calculated by dividing the ADC values from the nonenhancing cystic portion of the mass by the ADC values from contralateral normal-appearing white matter. Lesions were further differentiated based on presence, absence, or incompleteness of a T2 hypointensity rim. The mean (+/- standard deviation) ADC ratios were significantly higher in neoplasms than in abscesses (2.45 +/- 0.91 compared with 1.12 +/- 0:53, p < 0.01). The accuracy of ADC ratios in discriminating abscesses from neoplasms, determined by the area under the receiver operating characteristic curve (Az), was high: 0.91 +/- 0.04 (mean +/- standard error of the mean [SEM]). The threshold of 1.7 was associated with highest efficiency (87%) in discriminating abscesses from neoplasms. If only bacterial abscesses were analyzed compared with neoplasms, the Az increased to 0.96 +/- 0.03 (SEM). Using ADC ratios and T1 rim characteristics, 50 of 53 lesions were correctly classified (efficiency 94.3%). CONCLUSIONS: The accuracy of ADC ratios in discriminating brain abscesses from cystic or necrotic neoplasms is very high and can be further improved using T2 rim characteristics.     

Comparison of Two School-Based Smoking Prevention Programs among South African High School Students: Results of a Randomized Trial

Background  Smoking rates are projected to increase substantially in developing countries such as South Africa. Purpose  The aim of this study was to test the efficacy of two contrasting approaches to school-based smoking prevention in South African youth compared to the standard health education program. One experimental program was based on a skills training/peer resistance model and the other on a harm minimization model. Method  Thirty-six public schools from two South African provinces, KwaZulu-Natal and the Western Cape, were stratified by socioeconomic status and randomized to one of three groups. Group 1 (comparison) schools (n = 12) received usual tobacco use education. Group 2 schools (n = 12) received a harm minimization curriculum in grades 8 and 9. Group 3 schools (n = 12) received a life skills training curriculum in grades 8 and 9. The primary outcome was past month use of cigarettes based on a self-reported questionnaire. Result  Five thousand two hundred sixty-six students completed the baseline survey. Of these, 4,684 (89%) completed at least one follow-up assessment. The net change in 30-day smoking from baseline to 2-year follow-up in the control group was 6% compared to 3% in both harm minimization (HM) and life skills training (LST) schools. These differences were not statistically significant. Intervention response was significantly moderated by both gender and race. The HM intervention was more effective for males, whereas the life skills intervention was more effective for females. For black African students, the strongest effect was evident for the HM intervention, whereas the strongest intervention effect for “colored” students was evident for the LST group. Conclusion  The two experimental curricula both produced similar overall reductions in smoking prevalence that were not significantly different from each other or the control group. However, the impact differed by gender and race, suggesting a need to tailor tobacco and drug use prevention programs. More intensive intervention, in the classroom and beyond, may be needed to further impact smoking behavior.