مجله دانشکده پزشکی اصفهان
پیاپی 643 (هفته سوم آذر 1400)

Overactivation of P/Q type of calcium channels leads to neurological disorders. The venom of Agelena labyrinthica consists of substances which can inhibit this channel. One of the most important compounds is agatoxin. This study aimed to investigate the preventive and therapeutic effects of total venom or agatoxin component on kainic acid-induced amnesia.

The spider, Agelena labyrinthica, was collected from Mazandaran Province, Iran, and their total venom was extracted. The agatoxin fraction was purified using the fast protein liquid chromatography (FPLC) method. The total venom or agatoxin was injected into the rat hippocampus before or after injection of kainic acid. A week after the drug injection, the memory of animals was assessed using Morris water maze (MWM) task.

Kainic acid significantly reduced the time spent in the target quadrant (TQ) in water maze compared to the control group (P < 0.001). Intra-hippocampal injection of total venom or agatoxin fraction either before or after kainic acid caused a significant increase in TQ time compared to kainic acid group (P < 0.001). Of note, their injection before the kainic acid increased the TQ time more than injection after the kainic acid. In comparison to total venom, agatoxin fraction remarkably increased the TQ time.

Total venom and agatoxin fraction prevented the memory impairment due to the excitotoxicity of kainic acid. The effect of agatoxin was greater than total venom. These two substances showed less ameliorative effect when administered after kainic acid injection.

Streptococcus agalactiae, a group B streptococcus (GBS), is commonly found in the vagina, rectum, and urinary tract of pregnant and non-pregnant women. This bacterium, not only causes neonatal infections, but also causes invasive diseases including urinary tract infections in pregnant women and non-pregnant adults. Penicillin and macrolides are the main antibiotics in the treatment of GBS infections, but the prevalence of resistant strains is increasing. On the other hand, the distribution of bacterial capsule serotypes varies depending on the sampling time, geographical location and type of sample, and it is necessary to determine the most common type of capsule type in preparing a suitable vaccine. The aim of this study was to investigate the antimicrobial resistance and capsular serotypes in GBS isolated from urine samples of patients referred to Yazd City medical centers, Iran.

This descriptive cross-sectional study was performed on 85 GBS isolates from 6068 urine positive culture samples for phenotypic survey and determining the pattern of antibiotic resistance to antibiotic disks using Kirby-Bauer method. Moreover, capsular serotypes of isolates were determined by multiplex polymerase chain reaction (PCR).

The frequency of GBS in urinary samples was 1.4%. The highest antibiotic resistance was to tetracycline (97.6%) and the lowest to penicillin (0.0%). The predominant capsular serotype was III (50.6%) followed by serotypes Ib (14.1%), V (12.9%), IV (7.1%), and II (5.9%). 9.4% of isolates were non-typeable.

The prevalence of GBS in urinary specimens was low, and capsular serotype III was predominant as in previous studies. Macrolide resistance is increasing in urinary GBS isolates.

The aim of this study was to investigate the prevalence of antibiotic resistance in methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from clinical specimens.

This study was performed on clinical samples in a teaching hospital in Isfahan City, Iran. Isolates of Staphylococcus aureus were identified using standard laboratory and molecular assessments. Antibiotic resistance pattern of MRSA isolates was evaluated by disk diffusion method based on the Clinical and Laboratory Standards Institute (CLSI) protocol. Polymerase chain reaction (PCR) technique was performed for the identification of mecA gene.

125 strains of Staphylococcus aureus were identified by biochemical and molecular methods. The prevalence of methicillin-resistant strains was 40%. The highest number of MRSA isolates was related to wound samples, and the highest resistance of MRSA strains after resistance to penicillin (100%), was to the antibiotics erythromycin and ciprofloxacin (92%). 17 different antibiotic patterns were identified among MRSA strains.

The data revealed that 40% of Staphylococcus aureus strains were methicillin-resistant. The highest number of MRSA isolates was related to wound samples.