Accumulation and human health risk assessment of trace elements in two fish species, Cirrhinus mrigala and Oreochromis niloticus, at Tarukri Drain, District Rahimyar Khan, Punjab, Pakistan.

The toxic discharge of heavy metals into the water affects the aquatic ecosystem as well as the human population interacting with it because of their toxicity, bioaccumulation, long persistence, and transfer through the food chain. Thus, it is very important to conduct studies to determine the level of heavy metal pollution in order to better control, manage, and preserve the pollution of aquatic ecosystems. This study assessed heavy metal contamination in fish and its associated health risk to the population around the Tarukri Drain, Punjab, Pakistan. Two fish species (Oreochromis niloticus and Cirrhinus mrigala) were collected from three different sites in two different seasons. Collected fish were analyzed for cadmium (Cd), iron (Fe), lead (Pb), nickel (Ni), and zinc (Zn) accumulation using atomic absorption spectrometer (AAS). Furthermore, the human health risks associated with the consumption of affected fish were also assessed. Target hazardous quotient for seasonal consumers was between 0.12, - 1.58 × 10-4, and 0.54 - 3.28 × 10-4 (mg/kg) in O. niloticus and C. mrigala, respectively. While for regular consumers it was between 0.28-3.71 × 10-4 and 1.27-7.68 × 10-4 (mg/kg) in O. niloticus and C. mrigala respectively for the studied heavy metals. Fish sampled from Sadiqabad contained the highest concentration of heavy metals. The analysis of fish organs (kidney, liver, and muscles) showed heavy metal accumulation in the order of kidney > liver > muscles (p < 0.00). The obtained results showed that heavy metal contaminations in both fish species were within the permissible limits recommended by the World Health Organization (WHO). Both sampling seasons (i.e., summer and winter) showed a non-significant difference in heavy metal concentration. The calculated total target hazardous quotient across all heavy metals remained < 1 with only one exception. The carcinogenic risk assessment of heavy metals showed a non-significant effect in both fish species.

Surface-enhanced Raman spectral investigation of antibacterial activity of zinc 3-chlorobenzoic acid complexes against Gram-positive and Gram-negative bacteria.

BACKGROUND: Raman spectroscopy is an effective tool for determining the antibacterial actitivites of organometallic compounds against different bacterial strains. OBJECTIVES: The purpose of current study is to check the anibacterial activites of ligand (3-chlorobenzoic acid) and its respective zinc complex against gram positive and gram-negative bacterial strains by using surface enhanced Raman spectroscopy (SERS). METHODS: The ligand (3-chlorobenzoic acid) and its respective zinc complex caused different biochemical changes in gram-positive and gram-negative bacterial strains such as lipid contents, DNA/RNA contents, proteins contents, peptidoglycan contents and bacterial spore contents which can be observed with different SERS spectral features. Furthermore, PCA was employed for differentiating the mechanism of action of zinc complexes against gram-positive bacterial strain and gram-negative bacterial strain. RESULTS: Surface enhanced Raman spectroscopy (SERS) has been employed for analyzing the antibiotic activities of 3-chlorobenzoic acid ligands and their respective zinc complexes against Escherichia coli (gram-negative) and Bacillus subtilis (gram-positive) bacterial strains. The bioactivity assay and SERS spectral results clearly show that the complex causes more degradation in both bacterial cells (E. coli and B. subtilis) as compared to ligand. Furthermore, PCA was employed for differentiating the mechanism of action of zinc complexes against gram-positive bacterial strain and gram-negative bacterial strain. CONCLUSION: SERS technique along with chemometric tools have successfully differentiated the antibiotic activities of 3-chlorobenzoic acid ligands and their respective zinc complexes against Escherichia coli (gram-negative) and Bacillus subtilis (gram-positive) bacterial strains.

Usefulness of Temporary Pacing in Patients With New Left Bundle Branch Block During Transcatheter Aortic Valve Implantation.

New-onset left bundle branch block (NLBBB) is the most common complication after transcatheter aortic valve implantation (TAVI). Expert consensus recommends temporary transvenous pacemaker (TTVP) support for 24 hours in these patients. To date, no study has examined TTVP use during the index hospitalization in detail. Therefore, we aimed to assess TTVP use in patients with TAVI who developed NLBBB. In this prospective observational study, we performed a detailed analysis of 24-hour telemetry in patients who developed NLBBB during TAVI. Baseline characteristics and procedural and postprocedural data were recorded. The primary outcome was pacing by the TTVP. We evaluated inappropriate TTVP use, electrophysiology study findings, permanent pacemaker (PPM) implantation, and NLBBB resolution. A total of 83 patients (74.4 ± 8.7 years, 41% female) developed NLBBB during TAVI. During index hospitalization, 1 patient (1%) required TTVP because of complete heart block and received a PPM. Five of the 83 (6%) patients were inappropriately paced, and 1 patient (1%) had ventricular fibrillation, likely secondary to TTVP. A total of 34 patients (41%) underwent electrophysiology study during hospitalization, with 4 of 83 (5%) subsequently receiving a PPM. One (1%) patient died during hospitalization, and 9 patients were lost to follow-up because of the COVID-19 pandemic. Of the remaining 73 patients with a 30-day follow-up, NLBBB had resolved in 36 (49%) at 30 days, and 2 (3%) were readmitted with complete heart block and received PPM. In conclusion, in patients with TAVI who develop NLBBB, temporary pacing is rarely necessary, may carry additional risks to the patient, and prolong hospitalization time.

Are medical undergraduates more likely to indulge in substance abuse than non-medical undergraduates? A survey from Karachi.

OBJECTIVE: To determine frequency of substance abuse and the commonest substance of abuse among medical and non-medical undergraduates. STUDY DESIGN: Survey report. PLACE AND DURATION OF STUDY: Dow International Medical College, Karachi, from June 2012 to August 2012. METHODOLOGY: Semester VIII students from Dow International Medical College, Dow University of Health Sciences who visited the selected medical and non-medical universities, data collected through self responding questionnaire which was handed out to the participants. Data was collected from 4 medical and 4 non-medical universities. All responding undergraduate students in selected universities were included. Data was maintained and analyzed on SPSS version 16 for descriptive statistics. RESULTS: Total number of responders was 572 with male: female ratio of 1.23: 1.0 and mean age of 21.76 ± 2.168 years. Frequency of regular substance abuse was 20.1%. Males were abusing substance more than females, ratio being 4.7: 1.0 among abusers. The most common substance of abuse was tobacco. Frequency of regular substance abuse in nonmedical undergraduates was 29.4% which was higher than medical graduates (13.4%). CONCLUSION: Substance abuse among undergraduates in selected universities in Karachi was overall 20.1%. Male nonmedical undergraduates were more frequently using such substances; tobacco being the most common.