مجله دانش و تندرستی در علوم پایه پزشکی
سال هفدهم شماره 4 (زمستان 1401)

 Nowadays, methamphetamine addiction among teenagers and young people has attracted great concern in Iran. Long-term use of methamphetamine damages the brain's dopaminergic, serotonergic, and metabolic systems. Moreover, due to the effects of neurotoxicity in the brain, the patient suffers from cognitive disorders such as memory and learning disorders, mood disorders, and anxiety. Usnic acid has various biological properties, including antioxidant and anti-inflammatory activities. Therefore, the purpose of this study was to investigate the protective effects of usnic acid against the neurotoxicity of methamphetamine.

Methamphetamine neurotoxicity was induced by 40 mg/kg of METH in four intraperitoneally (IP) injections (e.g., 4×10 mg/kg q. 2-h, IP.). Usnic acid (25 mg/kg) was inserted at 30- min, 24-h, and 48 h after the final injection of METH. The Morris water maze test was used to study spatial memory. The brains were removed for biochemical assessments and Nissl staining.

Behavioral tests show that usnic acid treatment could significantly improve spatial memory deficits and learning (P<0.05) versus the METH group. Usnic acid treatment significantly increased superoxide dismutase (P<0.01) and reduced malondialdehyde (P<0.05). Moreover, usnic acid significantly reduced necrosis cell death (P<0.05) in the CA1 area of the hippocampus.

According to the findings, usnic acid improves memory and learning function in rats by reducing cell death.

Irisin is one of the myokines produced by skeletal muscle in response to exercise. Recent studies suggested that circulating irisin may play a vital role in bone metabolism. The present study aimed to investigate the effect of six weeks of resistance training on serum irisin, parathormone, and alkaline phosphatase levels in overweight postmenopausal women.

The 24 overweight postmenopausal women (51.87±2.30 years, 28.59±0.80 kg/m2) were selected and randomly divided into control and experimental groups equally. The experimental group performed a resistance training program for six weeks (3 sessions per week and one hour for each session). Exercises performed with an average intensity of 60 to 75% of a maximum repetition with a professional trainer. Also, fasting blood sampling was performed 24 hours before and 48 hours after the last training to assess irisin, parathormone, and alkaline phosphatase.

The results showed that six weeks of resistance training significantly increased irisin (P=0.04) and parathormone (P=0.05) in postmenopausal women but had no significant effect on alkaline phosphatase.

The results suggest that resistance training can be used as an appropriate exercise to increase the amount of irisin and some bone metabolism factors in postmenopausal overweight women. According to the evaluated irisin and parathormone values, Irisin might be the "connector" between bone health and physical activity.

In recent years, an outbreak of a new coronavirus, scientifically known as SARS-CoV-2, has led to a worldwide new infectious disease called Covid-19. Based on some reports, this virus stays after infection in the feces and consequently in the wastewater up to seven months, so examining its presence in the wastewater can be useful to understand how the disease is distributed in different parts of the city or region. This study aimed to investigate the presence of the SARS-CoV-2 virus in different parts of the Shahroud city wastewater collection network and treatment plant.

The 35 wastewater samples were collected from different partsof the wastewater collection network and wastewater treatment plant of Shahroud city. The samples were immediately transferred to the SARS-CoV-2 reference laboratory and concentrated by the polyethylene glycol (PEG) method. After extraction of the virus genome, the viral genome was amplified to check the presence of this virus by PCR method.

The results showed that 11 of the 35 wastewater collected samples were positive. All samples taken from the influent of the municipal wastewater treatment plant were positive. Also, except for one, in all of the samples taken from the effluent of the municipal wastewater treatment plant and Imam Hossein (AS) Hospital wastewater plant, coronavirus was observed. However, only one sample taken from the wastewater collection network of Shahroud city was positive.

Due to the confirmation of the presence of Coronavirus in the wastewater collection network and treatment plant, regular monitoring of municipal wastewater is recommended to predict the spread of a new wave of disease in the community.

Adipose-derived stem cells (ADSCs) are the most common stem cell types used for treating a variety of diseases and also improve wound healing in preclinical and clinical trials. Human amniotic membrane (HAM) is one of the biological substitutes with specific potential to be applied in tissue engineering. Piperonylic acid (PA) is a small molecule extracted from black Piper nigrum that can activate signals associated with cell survival, growth, and proliferation.

To evaluate the viability and proliferation of cells, we decellularized HAM and human adipose-derived stem cells (hADSCs) seeded on DHAM inthe presence of piperonylic acid as a small molecule in culture media. Bax and Bcl2 gene expression as apoptosis-related genes was also studied by real-time PCR.

HAM decellularization was confirmed through the H&E and PI staining and DNA content assay. The viability and proliferation of hADSCs seeded onDHAM showed a significant increase in the presence of 75 μM PA. Cell cultivation on DHAM demonstrated significantly decreased Bax gene expression and increased Bcl2 gene expression.

Based on our findings, DHAM as a bio-scaffold and PA can improve the viability and proliferative potential of hADSCs in vitro. PA with growth factor-like properties can be used in various tissues engineeringand in vitro cell cultures.

In this study, the effects of aerobic exercises and encapsulated ginger extract (GE) into chitosan nanoparticles (CNPs) were investigated on atrial natriuretic peptide (ANP) gene expression and cardiac histopathology in rat models of myocardial infarction.

The 25 male rats were divided into five groups: Isop (85 mg/kg), Isop + CNPs, Isop + GE-CNPs, Isop + AE, and Isop + GE-CNPs + AE. The rats performed AE on a rodent treadmill five days per week for six weeks. GE-CNPs were gavaged to rats at a dose of 500 mg/kg for six weeks. After the end of the treatment period, the expression of ANP genes was carried outby Real-Time PCR.

Based on our findings, the highest amount of collagen deposition was in the heart tissue of patient groups and the patient group treated with chitosan nanoparticles (P<0.05). Besides, the results of real-time PCR showed that the changes in ANP gene expression were significant only in the groups treated with aerobic exercise and ginger extract (P<0.05).

Regular aerobic exercises with nano-drug supplements such as ginger extract encapsulated into CNPs can reduce cardiac fibrosis and regulate ANP gene expression.

Growth differentiation factor-15 (GDF-15) is a marker of inflammation, oxidative stress and it is associated with adverse prognosis in cardiovascular disease. GDF-15 as a predictor for various types of cardiovascular diseases such as heart failure, are affected by training and sports activity. The effect of eight weeks of resistance, aerobic, and combined training on the salivary levels of GDF-15 in active older men was investigated.

The 36 cases were randomly divided into three groups of 12 (1. resistance training, 2. aerobic training, and 3. combined training). The serum GDF-15 salivary value in cases was estimated and recorded using a sandwich ELISA by special kits. After eight weeks of training protocols the datawere analyzed by paired t-test and Scheffe post hoc test to examine the differences between groups by SPSS software.

The results showed that the amount of salivary GDF-15 significantly increased after aerobic exercise by 6.4%, decreased after resistance training by 18.05%, and was unchanged after combination training.

Based on our findings, surprisingly, resistance exercise had a positive and significant effect on enhancing risk factors and reducing the salivary levels of GDF-15.

In clinical isolates of Staphylococcus aureus, the ica locus plays an important role in biofilm formation. However, its function in S. aureus clinical isolates carrying SCCmec locus and drug resistance is not clearly defined. This study aimsto measure the correlation between the ica locus and different types of SCCmec in clinical isolates of methicillin-resistant S. aureus (MRSA).

In this descriptive-analytical study, 89 isolates of S. aureus were isolated from different clinical samples using biochemical tests. Antibiotic resistance patterns and MRSA strains were identified by the disc diffusion method. SCCmec and ica locus was investigated using the PCR method.

Out of 89 clinical isolates of S. aureus, 41 MRSA strains were identified. The frequency of SCCmecI, SCCmecII, SCCmecIII, SCCmecIV, and SCCmecV genes was 21.9%, 26.8%, 31.7%, 17.1%, and 41.4%, respectively. In addition, icaA, icaB, icaC, and icaD were isolated from 29 isolates (32.58%), 11 isolates (12.35%), 17 isolates (19.10%),and 22 isolates (24.71%), respectively. The frequency of SCCmec types in the strains carrying the ica locus was significantly higher than in the strains without the ica locus (P≥0.05).

The circulation of ica locus genes plays a vital role in increasing the frequency of methicillin-resistant S. aureus strains and the distribution of SCCmec types in those strains.

Ectopic pregnancy is the most common cause of maternal mortality, while cesarean scar ectopic is one of the rarest of all ectopic pregnancies.Early diagnosis of this type ofpregnancyleads to better control of this situation.

A 28-year-old 28 weeks’ pregnant woman (G3P1Ab1L1) presented to the emergency department with the complaint of hematuria, labor pain, bleeding, and cervical dilation. The patient was taken to the operating room, considering her past surgical history of cesarean delivery. Due to the recreated placenta and ectopic pregnancy, hysterectomy and Cystorrhaphy were performed.

Cesarean scar ectopic is a type of extrauterine pregnancy that implants around the place of a previous pregnancy scar. This pregnancy may cause severe hemorrhage due to uterine rupture, accreta, and percreta placenta. Bladder invasion by the placenta percreta causes hematuria during pregnancy, so early diagnosis plays a critical role. Ultrasonography is a widely accessible method. As described in this case, a false negative result in ultrasonography causes extensive hemorrhage hysterectomy.

The ectopic pregnancy may occurs in the connective tissue around the site of a previous cesarean scar. This type of pregnancy can cause severe bleeding due to uterine rupture or placenta accreta and placental abruption. Placenta percarta invading the bladder causes hematuria during pregnancy and early diagnosis is very important and the most available diagnostic method is transvaginal ultrasound. A false negative diagnosis may lead to complications such as uncontrollable bleeding and hysterectomy as in this case.