The Zebrafish Model as a New Discovery Path for Medicinal Plants in the Treatment of Parkinson's Disease

Parkinson's disease (PD) is one of the most frequent degenerative central nervous system disorders affecting older adults. Dopaminergic neuron failure in the substantia nigra is a pathological sign connected with the motor shortfall of PD. Due to their low teratogenic and adverse effect potential, medicinal herbs have emerged as a promising therapy option for preventing and curing PD and other neurodegenerative disorders. However, the mechanism through which natural compounds provide neuroprotection against PD remains unknown. While testing compounds in vertebrates such as mice is prohibitively expensive and time-consuming, zebrafish (Danio rerio) may offer an appealing alternative because they are vertebrates and share many of the same characteristics as humans. Zebrafish are commonly used as animal models for studying many human diseases, and their molecular history and bioimaging properties are appropriate for the study of PD. However, a literature review indicated that only six plants, including Alpinia oxyhylla, Bacopa monnieri, Canavalia gladiate, Centella asiatica, Paeonia suffruticosa, and Stachytarpheta indica had been investigated as potential PD treatments using the zebrafish model. Only C. asiatica and B. monnieri were found to have potential anti-PD activity. In addition to reviewing the current state of research in this field, these plants' putative mechanisms of action against PD are explored, and accessible assays for investigation are made.

Potential Adverse Effects of COVID-19 Vaccines on Iranian Healthcare Workers: Comparison of Four Available Vaccines in Tehran: A Retrospective Cross-sectional Study

Objectives

This study aimed to compare four COVID-19 vaccines for their potential extensive side effects and the relationship between the side effects and age, body mass index (BMI), and history of COVID-19 infection.

Methods

This cross-sectional study was conducted from June to August 2021 among 1474 healthcare workers of seven selected hospitals in Tehran, Iran. All the subjects were vaccinated (91.7% received two doses and 8.3% received one dose) with one of four vaccines, Sputnik, Covaxin, AstraZeneca, and Sinopharm, at least 10 days before the study. The incidence of 47 side effects was measured after vaccination.

Results

Over half of the participants (59.4%; n = 876) were 20-29 years of age, with the mean and average BMI being 26.1±9.0 and 23.5±3.4, respectively; 36.0% (n = 530) were previously diagnosed with COVID-19. There was no significant relationship between age and the incidence of side effects for AstraZeneca, Sputnik, and Covaxin; however, the occurrence of side effects of Sinopharm was significantly higher (p < 0.001) among younger healthcare workers. There was no significant relationship between BMI and the incidence of side effects for all four vaccines. However, in the group with a history of COVID-19 disease, health care workers vaccinated with the Sinopharm vaccine showed significantly (p < 0.001) more complications. The occurrence rate of at least one adverse effect and referral to medical centers for AstraZeneca, Sputnik, Covaxin, and Sinopharm vaccines were 24.9-93.9%, 18.2-86.0%, 14.8-77.0%, and 3.5-37.2%, respectively. The highest and lowest rates were found for AstraZeneca and Sinopharm showing a significant (p < 0.001) difference. The most commonly observed side effects for the AstraZeneca vaccine included fever (64.4%), fatigue (62.5%), and muscle pain (59.9%); for Sputnik muscle pain (59.8%), fever (49.5%), and fatigue (49.5%); for Covaxin fever (49.2%), topical reaction (41.0), and fatigue (34.4%); and for Sinopharm fever (18.7%), topical reaction (17.9%), and fatigue (16.6%). Inactivated virus vaccines (Sinopharm and Covaxin) showed a lower (39.7%) occurrence rate of side effects compared to viral vector vaccines (AstraZeneca and Sputnik; 90.6%). The most likely time for the vaccines to exert side effects was the first 24 hours after vaccination.

Conclusions

We found no significant relationship between age, BMI, history of COVID-19 disease, and the incidence of side effects in healthcare workers vaccinated with any of the four vaccines. All four vaccines are safe and have controlled side effects.

Comparison of Side Effects of COVID-19 Vaccines: Sinopharm, AstraZeneca, Sputnik V, and Covaxin in Women in Terms of Menstruation Disturbances, Hirsutism, and Metrorrhagia: A Descriptive-Analytical Cross-Sectional Study

BACKGROUND

Present study assessed whether Sinopharm, AstraZeneca, Sputnik V, and Covaxin's vaccinated women<br />reveal a distinct incidence of menstruation disturbances, hirsutism, and metrorrhagia.<br />Materials and Methods: Data collection was performed from June to August 2021, and 427 women working in seven<br />selected hospitals in Tehran were studied in this descriptive-analytical cross-sectional study. All of these women had<br />received one or both doses of the vaccines with one of the assessed vaccines. Required data was collected via questionnaire<br />and imported to SPSS 16 for further assessment and analysis. Fisher's Exact Test and Chi-Squared test were<br />main statistical tests used to understand whether any significant relation exists or not.<br />Results: The participant's mean age and body mass index (BMI) were 29.78 ± 10.55 and 23.27 ± 3.82, respectively.<br />Three hundred ninety-five cases (92.4%) had received both doses of the vaccines. Also, 154 cases (36.1%) had a history<br />of COVID-19. A total of 38 cases (8.8%) of menstruation disturbances, 20 cases (4.6%) of metrorrhagia, and 7<br />cases (1.6%) of hirsutism were reported after receiving the vaccines. There was a significant difference among the<br />vaccinated groups with the vaccines as mentioned earlier in terms of menstruation disturbances (hypermenorrhea,<br />dysmenorrhea, Amenorrhea) (P=0.01). The highest and the lowest incidence of menstruation disturbances were recorded<br />in the group vaccinated with Covaxin (17.6%) and Sputnik V (5%), respectively. There was also no significant<br />difference amongst the vaccinated groups with the four vaccines regarding the incidence of metrorrhagia and<br />hirsutism (P=0.10 and P=0.12, respectively). There was no significant relationship between all three complications<br />incidence with the previous infection concerning all vaccines (coefficient=0.46, 1.27, -0.15 respectively for menstruation<br />disturbances, metrorrhagia, and, hirsutism).<br />Conclusion: Seemingly, Covaxin revealed the most side effects in terms of menstruation disturbances. As a result, professionals<br />must carry out several studies with reasonable samples to recommend the vaccine to those women confidently.

Military exercises, knee and ankle joint position sense, and injury in male conscripts: a pilot study

CONTEXT

The high incidence of lower limb injuries associated with physical exercises in military conscripts suggests that fatigue may be a risk factor for injuries. Researchers have hypothesized that lower limb injuries may be related to altered ankle and knee joint position sense (JPS) due to fatigue.

OBJECTIVE

To evaluate if military exercises could alter JPS and to examine the possible relation of JPS to future lower extremity injuries in military service.

DESIGN

Cohort study.

SETTING

Laboratory.

PATIENTS OR OTHER PARTICIPANTS

A total of 50 male conscripts (age = 21.4 ± 2.3 years, height = 174.5 ± 6.4 cm, mass = 73.1 ± 6.3 kg) from a unique military base were recruited randomly. main outcome measure(s): Participants performed 8 weeks of physical activities at the beginning of a military course. In the first part of the study, we instructed participants to recognize predetermined positions before and after military exercises so we could examine the effects of military exercise on JPS. The averages of the absolute error and the variable error of 3 trials were recorded. We collected data on the frequency of lower extremity injuries over 8 weeks. Next, the participants were divided into 2 groups: injured and uninjured. Separate 2 × 2 × 2 (group-by-time-by-joint) mixed-model analyses of variance were used to determine main effects and interactions of these factors for each JPS measure. In the second part of the study, we examined whether the effects of fatigue on JPS were related to the development of injury during an 8-week training program. We calculated Hedges effect sizes for JPS changes postexercise in each group and compared change scores between groups.

RESULTS

We found group-by-time interactions for all JPS variables (F range = 2.86-4.05, P < .01). All participants showed increases in JPS errors postexercise (P < .01), but the injured group had greater changes for all the variables (P < .01).

CONCLUSIONS

Military conscripts who sustained lower extremity injuries during an 8-week military exercise program had greater loss of JPS acuity than conscripts who did not sustain injuries. The changes in JPS found after 1 bout of exercise may have predictive ability for future musculoskeletal injuries.