CRISPR/Cas9 Technology: A Novel Approach to Obesity Research.

Gene editing technology, particularly Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) has transformed medical research. As a newly developed genome editing technique, CRISPR technology has strongly assisted scientists in enriching their comprehension of the roles of individual genes and their influences on a vast spectrum of human malignancies. Despite considerable progress in elucidating obesity's molecular pathways, current anti-obesity medications fall short in effectiveness. A thorough understanding of the genetic foundations underlying various neurobiological pathways related to obesity, as well as the neuro-molecular mechanisms involved, is crucial for developing effective obesity treatments. Utilizing CRISPR-based technologies enables precise determination of the roles of genes that encode transcription factors or enzymes involved in processes, such as lipogenesis, lipolysis, glucose metabolism, and lipid storage within adipose tissue. This innovative approach allows for the targeted suppression or activation of genes regulating obesity, potentially leading to effective weight management strategies. In this review, we have provided a detailed overview of obesity's molecular genetics, the fundamentals of CRISPR/Cas9 technology, and how this technology contributes to the discovery and therapeutic targeting of new genes associated with obesity.

The association between enteral nutrition with survival of critical patients with COVID-19.

BACKGROUND: Coronavirus disease 2019 (COVID-19) results in several complications and mortality in intensive care unit (ICU) patients. Limited studies have investigated the effect of enteral nutrition (EN) on the survival of COVID-19 patients in the ICU. The aim of this study was to investigate the association of EN with biochemical and pathological indices associated with mortality in ICU patients with COVID-19. METHODS: This case-control study was conducted on 240 patients with COVID-19 hospitalized in the ICU including 120 eventual nonsurvived as the cases and 120 survived patients as the controls. All of the patients received EN as a high protein high volume or standard formula. Data on general information, anthropometric measurements, and the results of lab tests were collected. RESULTS: The recovered patients received significantly more high protein (60.8% vs. 39.6%, p = .004) and high volume (61.6% vs. 42.3%, p = .005) formula compared to the nonsurvived group. Mortality was inversely associated with high volume (odds ratio [OR]: 0.45 confidence interval [CI]95%, p = .008) and high protein (OR: 0.42 CI95%, p = .003) formula. The results remained significant after adjusting for age and sex. Further adjustment for underlying diseases, smoking, body mass index, and the acute physiology and chronic health evaluation II (APACHE II) score did not change the results. CONCLUSION: The findings of the study showed that there was a significant inverse association between mortality and high volume and high protein formula in patients with COVID-19. Further investigation is warranted.

The Association of Iron Intake and Hypertension, Does Iron Intake Decrease Blood Pressure?

Previous studies reported that iron may have an indispensable role in the risk of hypertension (HTN). However, the result of the studies on the relationship between iron and risk of HTN is inconsistent. This study aimed to assess the association between the association of dietary iron intake and HTN in the Iranian population. This case-control study was conducted on 4184 people aged 35 to 70, including 1239 people with HTN and 2945 people with normal blood pressure (BP) in Sabzevar, Iran. Dietary intake was assessed using a food frequency questionnaire (FFQ). The Nutritionist IV software was used in terms of the assessment of dietary intake of iron. An inverse association was found between iron intake and HTN (OR = 0.97, CI 95%: 0.94-0.99, P = 0.04). The association remained significant after adjustment for age, gender, smoking, drinking alcohol, calorie intake, and BMI (OR = 0.94, CI 95%: 0.89-0.98, P = 0.01). As a conclusion, iron intake was inversely associated with HTN. Further longitudinal studies on the effect of iron intake on BP are required to confirm this finding.

Decoding contextual crosstalk: revealing distinct interactions between non-coding RNAs and unfolded protein response in breast cancer.

Breast cancer is significantly influenced by endoplasmic reticulum (ER) stress, impacting both its initiation and progression. When cells experience an accumulation of misfolded or unfolded proteins, they activate the unfolded protein response (UPR) to restore cellular balance. In breast cancer, the UPR is frequently triggered due to challenging conditions within tumors. The UPR has a dual impact on breast cancer. On one hand, it can contribute to tumor growth by enhancing cell survival and resistance to programmed cell death in unfavorable environments. On the other hand, prolonged and severe ER stress can trigger cell death mechanisms, limiting tumor progression. Furthermore, ER stress has been linked to the regulation of non-coding RNAs (ncRNAs) in breast cancer cells. These ncRNAs, including microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), play essential roles in cancer development by influencing gene expression and cellular processes. An improved understanding of how ER stress and ncRNAs interact in breast cancer can potentially lead to new treatment approaches. Modifying specific ncRNAs involved in the ER stress response might interfere with cancer cell survival and induce cell death. Additionally, focusing on UPR-associated proteins that interact with ncRNAs could offer novel therapeutic possibilities. Therefore, this review provides a concise overview of the interconnection between ER stress and ncRNAs in breast cancer, elucidating the nuanced effects of the UPR on cell fate and emphasizing the regulatory roles of ncRNAs in breast cancer progression.

Female infertility and dietary antioxidant index (DAI); a case-control study.

BACKGROUND: Adequate intake of natural antioxidants may improve female fertility. The aim of this study was to examine the link between female infertility and dietary antioxidant index (DAI). METHODS: This case-control study was conducted on 125 women with recently diagnosis of reduced ovarian reserves (AMH < 1.1) as the case group and 125 women with normal ovarian reserve as the control group in Rasht, Iran. The amount of food intake was assessed using the food frequency questionnaire (FFQ) and the DAI was calculated to estimate the antioxidant capacity of the diet. RESULTS: Regarding dietary intake, the infertile women had a lower intake of potassium (2789.25 ± 777 vs. 2593.68 ± 443 mg/d, P = 0.02), magnesium (204.12 ± 66 vs. 189.73 ± 34 mg/d, P = 0.03), copper (0.93 ± 0.40 vs. 0.82 ± 0.20 mg/d, P < 0.01), vitamin C (133.99 ± 46 vs. 122.62 ± 24 mg/d, P = 0.02), and fiber (14.53 ± 3 vs. 13.44 ± 2 g/d, P < 0.05), and a higher intake of cholesterol (205.61 ± 58 vs. 227.02 ± 46 mg/d, P < 0.01) than the control group (All P < 0.05). The DAI was negatively associated with infertility (OR: 0.94, CI 95%: 0.88-0.97, P = 0.03). The association remained significant after adjustments for age, BMI, the underlying diseases, fertility frequency, IVF failure, and calorie intake. CONCLUSION: Following an antioxidant-rich diet may reduce the risk of infertility. More longitudinal studies are warranted to confirm these results and discover the underlying mechanisms.

Financial burden of prostate cancer in the Iranian population: a cost of illness and financial risk protection analysis.

BACKGROUND: Prostate cancer is the second most common cancer in males worldwide and the third most common among Iran's male population. However, there is a lack of evidence regarding its direct and indirect costs in low and middle-income countries. This study intends to bridge the gap using a cost of illness approach, assessing the costs of prostate cancer from the perspectives of patients, society, and the insurance system. METHODS: Two hundred ninety seven patients were included in the study. Data for a 2-month period were obtained from patients registered at two hospitals (Tabriz, Tehran) in Iran in 2017. We applied a prevalence-based, bottom-up approach to assess the costs of the illness. We used the World Health Organization methods to measure the prevalence and investigate the determinants of catastrophic and impoverishing health expenditures. RESULTS: We determined the total costs of the disease for the patients to be IRR 68 million (PPP $ 5,244.44). Total costs of the disease from the perspective of the society amounted to IRR 700,000 million (PPP $ 54 million). Insurance companies expended IRR 20 million (PPP $ 1,558.80) per patient. Our findings show that 31% of the patients incurred catastrophic health expenditure due to the disease. Five point forty-four percent (5.44%) of the patients were impoverished due to the costs of this cancer. CONCLUSION: We found an alarmingly high prevalence of catastrophic health expenditures among prostate cancer patients. In addition, prostate cancer puts a substantial burden on both the patients and society.

The association between obesity with treatment duration, ICU length of stay and the risk of death in critically ill patients with COVID-19.

BACKGROUND: Despite the confirmed association between higher BMI with increased risk of the acute respiratory distress syndrome (ARDS), the association between obesity with mortality in critically ill patients with coronavirus disease 2019 (COVID-19) is not clear. The present study aimed to investigate the association between obesity with treatment duration, ICU length of stay, and the risk of death in critically ill patients with COVID-19. METHODS: This case-control study was performed on 223 patients with COVID-19 including 148 surviving patients as the control group and 75 eventually dead patients as the case group in Rasht, Iran. Data on demographic factors, comorbidities, anthropometric measurements, the length of hospitalization and the mortality were obtained from patients' medical records. RESULTS: The mortality rate was significantly associated with weight (OR = 1.04, 95% CI: 1.002-1.083, p = .04), but not with BMI after adjustments for age, gender, length of stay in ICU, chronic diseases and smoking. The results did not change after further adjustments for biochemical and pathological factors. CONCLUSIONS: Weight was positively associated with mortality after controlling for confounding variables. Further studies should consider the patient's body composition such as fat mass to establish the relationship between obesity and COVID-19 outcomes.

Association of IFIH1 and DDX58 genes polymorphism with susceptibility to COVID-19.

Pattern recognition receptors of the innate immune system, such as RIG-I and MDA5, are responsible for recognizing viruses and inducing interferon production. Genetic polymorphisms in the coding regions of RLR may be associated with the severity of COVID-19. Considering the contribution of the RLR signaling in immune-mediated reactions, this study investigated the association between three SNP in the coding region of IFIH1 and DDX58 genes with the susceptibility to COVID-19 in the Kermanshah population, Iran. 177 patients with severe and 182 with mild COVID-19 were admitted for this study. Genomic DNA was extracted from peripheral blood leukocytes of patients to determine the genotypes of two SNPs, rs1990760(C>T) and rs3747517(T>C) IFIH1 gene and rs10813831(G>A) DDX58 gene using PCR-RFLP method. Our results showed that the frequency of the AA genotype of rs10813831(G>A) was associated with susceptibility to COVID-19 compared to the GG genotype (p = 0.017, OR = 2.593, 95% CI 1.173-5.736). We also observed a statistically significant difference in the recessive model for SNPs rs10813831 variant (AA versus GG + GA, p = 0.003, OR = 2.901, 95% CI 1.405-6.103). Furthermore, No significant association was found between rs1990760 (C>T) and rs3747517(T>C) of IFIH1 gene polymorphisms with COVID-19. Our findings suggest that DDX58 rs10813831(A>G) polymorphism may be associated with COVID-19 severity in the Kermanshah population, Iran.

Multifunctional Self-Assembled Peptide Hydrogels for Biomedical Applications.

Self-assembly is a growth mechanism in nature to apply local interactions forming a minimum energy structure. Currently, self-assembled materials are considered for biomedical applications due to their pleasant features, including scalability, versatility, simplicity, and inexpensiveness. Self-assembled peptides can be applied to design and fabricate different structures, such as micelles, hydrogels, and vesicles, by diverse physical interactions between specific building blocks. Among them, bioactivity, biocompatibility, and biodegradability of peptide hydrogels have introduced them as versatile platforms in biomedical applications, such as drug delivery, tissue engineering, biosensing, and treating different diseases. Moreover, peptides are capable of mimicking the microenvironment of natural tissues and responding to internal and external stimuli for triggered drug release. In the current review, the unique characteristics of peptide hydrogels and recent advances in their design, fabrication, as well as chemical, physical, and biological properties are presented. Additionally, recent developments of these biomaterials are discussed with a particular focus on their biomedical applications in targeted drug delivery and gene delivery, stem cell therapy, cancer therapy and immune regulation, bioimaging, and regenerative medicine.

Nanostructured multifunctional stimuli-responsive glycopolypeptide-based copolymers for biomedical applications.

Inspired by natural resources, such as peptides and carbohydrates, glycopolypeptide biopolymer has recently emerged as a new form of biopolymer being recruited in various biomedical applications. Glycopolypeptides with well-defined secondary structures and pendant glycosides on the polypeptide backbone have sparked lots of research interest and they have an innate ability to self-assemble in diverse structures. The nanostructures of glycopolypeptides have also opened up new perspectives in biomedical applications due to their stable three-dimensional structures, high drug loading efficiency, excellent biocompatibility, and biodegradability. Although the development of glycopolypeptide-based nanocarriers is well-studied, their clinical translation is still limited. The present review highlights the preparation and characterization strategies related to glycopolypeptides-based copolymers, followed by a comprehensive discussion on their biomedical applications with a specific focus on drug delivery by various stimuli-responsive (e.g., pH, redox, conduction, and sugar) nanostructures, as well as their beneficial usage in diagnosis and regenerative medicine.

Role of curcumin on miR-26a and its effect on DNMT1, DNMT3b, and MEG3 expression in A549 lung cancer cell.

CONTEXT: Most of the patients diagnosed with non-small cell lung cancer (NSCLC) are in their advanced stages and as a result might not be cured in spite of the advances in aimed therapy. In the recent years, the role of noncoding RNAs (ncRNAs) has been expanded to cancer as potential targets for RNA-based epigenetic therapies. Curcumin, as an active ingredient, is associated with epigenetic alterations, and it might modulate the expression of tumor suppressor and oncogenic microRNAs. MATERIALS AND METHODS: In this study, we investigated the RNA-based epigenetic effects of curcumin on NSCLC, and the effect of curcumin on A549 cell viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The expression of miR-26a, MEG3, DNA methyltransferase 1 (DNMT1), and DNMT3 beta (DNMT3b) was assessed by quantitative polymerase chain reaction. STATISTICAL ANALYSIS USED: Data analysis was done using Prism®6 software (GraphPad Software, Inc., La Jolla, CA, USA), and statistical analysis was performed using t-test between control and vitality samples. RESULTS: The results showed a significant increase (P < 0.05) of miR-26a expression which in turn was associated with a significant decrease (P < 0.05) in expression of DNMTs and subsequently a significant increase in MEG3 expression (P < 0.05) in A549 cell line after adding curcumin in the media. CONCLUSION: Considering all the data together, we could speculate the role of curcumin in ceasing the progression of cancer in its early stages and might be considered a potential drug for the treatment of NSCLC-derived lung cancer by establishing a meaningful relationship between epigenetic mechanisms and ncRNAs.

Evaluation of the relationship between IL-6 gene single nucleotide polymorphisms and the severity of COVID-19 in an Iranian population.

BACKGROUND: Emerged coronavirus disease 2019 (COVID-19) is a pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-COV-2). Disease severity is associated with elevated levels of proinflammatory cytokines, such as interleukin-6 (IL-6). Genetic polymorphisms in the regulatory regions of cytokine genes may be associated with differential cytokine production in COVID-19 patients. This study aimed to investigate the association between three potentially functional single-nucleotide polymorphisms (SNPs) in the promoter region of IL-6 and the severity of susceptibility to COVID-19 in an Iranian population. METHODS: In total, 346 individuals (175 patients with severe COVID-19 and 171 patients with mild COVID-19) were recruited for this cohort study. Genomic DNA was extracted from peripheral blood leukocytes of patients to determine the genotypes of three selected SNPs (rs1800795 (-174 G > C), rs1800796 (-572 G > C), and rs1800797 (-597 G > A)) in the promoter region of the IL-6 gene using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS: There were no significant differences in the genotype or allele distribution of selected SNPs (rs1800795 (-174 G > C), rs1800796 (-572 G > C), and rs1800797 (-597 G > A)) in the promoter region of the IL-6 gene in patients with severe COVID-19 and patients with mild COVID-19. DISCUSSION: Our study indicated that these SNPs are not associated with COVID-19 severity in the Kurdish population from Kermanshah, Iran.

COVID-19: A New Horizon in Congenital Heart Diseases.

Objective: Previous studies have demonstrated that both children and adult patients with a history of congenital heart disease (CHD) are at high risk for coronavirus disease 2019 (COVID-19) infection. This study investigates the status of COVID-19 infection among children undergoing surgical repair within the past 2 years. Methods: All alive patients operated on in a tertiary referral center between March 2018 and March 2020 were recruited in the present study. Detailed demographics, past medical and surgical history, and physical examination were reviewed for each patient. During the COVID-19 pandemic, data regarding the patient's status were collected by telephone survey from April 15 to April 30, 2020. Results: A total number of 210 patients are analyzed in this study. Participants' median age was 21.59 months [interquartile range (IQR) = 12-54.67], and 125 (59.5%) were female. The median interval between surgery and COVID-19 assessment was 305 days (IQR = 215-400). In addition, 67 (32%) patients used angiotensin receptor blocker (ARB)/angiotensin-converting enzyme (ACE) inhibitor (spironolactone and/or captopril). Sixteen patients (7.6%) were symptomatic and had positive chest CT results and/or RT-PCR compared to the previously reported prevalence of COVID-19 among the pediatric population (2.4% of children with <18 years of age); the prevalence of COVID-19 among the patients operated on due to CHD in the present study was significantly higher (p = 0.00012). Two patients were admitted to the intensive care unit (ICU); one patient was discharged 2 weeks later with acceptable status, and one patient died 2 days after ICU admission due to cardiac and respiratory arrest and myocarditis. The complexity of the underlying cardiac disorders was not different between patients with low risk (p = 0.522), suspicious patients (p = 0.920), and patients positive for COVID-19 (p = 0.234). The ARB/ACE inhibitor consumption was not associated with the COVID-19 infection [p = 0.527, crude odds ratio (OR) = 1.407, 95% CI = 0.489-4.052]. Conclusion: Children with a history of previous CHD surgery are more susceptible to infections, especially those infections with pulmonary involvements, as the lung involvement could cause worsening of the patient's condition by aggravating pulmonary hypertension. The results of the current study indicate that these patients are more prone to COVID-19 infection compared to the healthy children population.

CD44 polymorphisms and its variants, as an inconsistent marker in cancer investigations.

Among cell surface markers, CD44 is considered the main marker for identifying and isolating the cancer stem cells (CSCs) among other cells and has attracted significant attention in a variety of research areas. Many studies have shown the essential roles of CD44 in initiation, metastasis, and tumorigenesis in different types of cancer; however, the validity of CD44 as a therapeutic or diagnostic target has not been fully confirmed in some other studies. Whereas the association of specific single nucleotide polymorphisms (SNPs) in the CD44 gene and related variants with cancer risk have been observed in clinical investigations, the significance of these findings remains controversial. Here, we aimed to provide an up-to-date overview of recent studies on the association of CD44 polymorphisms and its variants with different kinds of cancer to determine whether or not it can be used as an appropriate candidate for cancer tracking.

In vitro evaluation of ferutinin on proliferation and osteogenesis differentiation in human unrestricted Somatic stem cells.

Osteoporosis is a common disease in post-menopausal women. The increased risk of breast cancer and malignancy with hormone replacement, hampers its wide-usage. Phytoestrogens are known to have selective estrogen receptor modulator activity. The present study aims to determine how ferutinin affects unrestricted human Somatic Stem Cells (USSCs) osteogenic differentiation. The effect of ferutinin on USSCs proliferation was assessed by MTT assay while osteogenesis was evaluated using Alkaline Phosphatase Activity (ALP), calcium deposition and Alizarin Red Staining. Quantitative real-time PCR was applied to examine the expression of bone specific genes such as osteocalcin, Runx2, and BMP-2. Ferutinin (5-15 µg/mL) could positively impact on the proliferation of cells in a dose-dependent manner. Also, ALP enzyme activity and calcium deposition were enhanced in the presence of ferutinin. Based on real-time PCR results, ferutinin could increase the expression of bone marker genes. The pattern of ferutinin effect on gene expression is similar to standard synthetic estrogen, 17-ß-estradiol. In the presence of the estrogen activity inhibitor (ICI), the effect of ferutinin on ALP and gene level was diminished. In conclusion, ferutinin may be considered as a potential candidate for the stem cell therapy in osteoporosis.

Promoted chondrogenesis of hMCSs with controlled release of TGF-ß3 via microfluidics synthesized alginate nanogels.

The field of cartilage tissue engineering has been evolved in the last decade and a myriad of scaffolding biomaterials and bioactive agents have been proposed. Controlled release of growth factors encapsulated in the polymeric nanomaterials has been of interest notably for the repair of damaged articular cartilage. Here, we proposed an on-chip hydrodynamic flow focusing microfluidic approach for synthesis of alginate nanogels loaded with the transforming growth factor beta 3 (TGF-ß3) through an ionic gelation method in order to achieve precise release profile of these bioactive agents during chondrogenic differentiation of mesenchymal stem cells (MSCs). Alginate nanogels with adjustable sizes were synthesized by fine-tuning the flow rate ratio (FRR) in the microfluidic device consisting of cross-junction microchannels. The result of present study showed that the proposed approach can be a promising tool to synthesize bioactive -loaded polymeric nanogels for applications in drug delivery and tissue engineering.

Ethyl Acetate Extract of Licorice Root (Glycyrrhiza glabra) Enhances Proliferation and Osteogenic Differentiation of Human Bone Marrow Mesenchymal Stem Cells.

Glycyrrhiza glabra (G. glabra) has been used as a flavoring and sweetener agent, in addition to its therapeutic properties. It is rich in phytoestrogen and may prevent osteoporosis caused by estrogen deficiency; however, there is no evidence for its effects on proliferation and osteogenesis in mesenchymal stem cells. So, we were encouraged to investigate whether the ethyl acetate extract of licorice root as a source of phytoestrogen can act similar to estrogen in cell culture. Furthermore, the analysis of the licorice extract (LE) based on HPLC-DAD-ESI-MS indicated that LE comprises phytoestrogen compounds, such as glabridin and glabrene. In this study, the effects of LE on proliferation of human bone-marrow mesenchymal stem cells (hBM-MSCs) were investigated using MTT assay. In addition, its effects on the osteogenesis were evaluated using alkaline phosphatase activity (ALP), calcium deposition, and bone specific gene expression such as ALP, osteocalcin, Runx2, and BMP-2. The quantitative gene expression was studied by real-time RT-PCR. Our results showed a significant increase in proliferation in presence of LE in concentration 10-50 µg/mL. The differentiation of hBM-MSCs increased in doses of LE (10-25 µg/mL) compared to the control group. The effects of LE were similar to those of 17ß-estradiol (E2) (10-8 M) and were abolished by ICI 182,780 an antagonist of estrogen receptor (ER) (10-7), indicating that the stimulatory effects of LE occur through estrogen receptor-mediated mechanism . Taking these into account, LE may be a potential candidate for prevention of osteoporosis in menopausal women.

Dedifferentiation Effects of Rabbit Regenerating Tissue on Partially Differentiated Cells.

Cell Stemness can be achieved by various reprogramming techniques namely, somatic cell nuclear transfer, cell fusion, cell extracts, and introduction of transcription factors from which induced pluripotent stem cells (iPSCs) are obtained. iPSCs are valuable cell sources for drug screening and human disease modeling. Alternatives to virus-based introduction of transcription factors include application of DNA-free methods and introduction of chemically defined culturing conditions. However, the possibility of tumor development is still a hurdle. By taking advantage of NTERA-2 cells, a human embryonal carcinoma cell line, we obtained partially differentiated cells and examined the dedifferentiation capacity of regenerative tissue from rabbit ears. Results indicated that treatment of partially differentiated NTERA-2 cells with the regenerating tissue-conditioned medium (CM) induced expression of key pluripotency markers as examined by real-time polymerase chain reaction, flow cytometry, and immunocytochemistry techniques. In this study, it is reported for the first time that the CM obtained from rabbit regenerating tissue contains dedifferentiation factors, taking cells back to the pluripotency. This system could be a simple and efficient way to reprogram the differentiated cells and generate iPSCs for clinical applications as this system is not accompanied by any viral vector, and reprograms the cells within 10 days of treatment. The results may convince the genomic experts to study the unknown signaling pathways involved in the dedifferentiation by regenerating tissue-CM to authenticate the reprogramming model.

Epidemiological Profile of Hepatitis B Virus Infection in Iran in the Past 25 years; A Systematic Review and Meta-analysis of General Population Studies.

BACKGROUND Chronic hepatitis B virus (HBV) infection is one of the most important health problems worldwide with a high rate of morbidity and mortality. It is a major risk factor for cirrhosis and liver cancer. Currently, Iran is located in the intermediate HBV zone; however, recent studies have provided some evidence indicating an epidemiological change in the country. The aim of this study was to estimate the prevalence of HBV in Iran. METHODS A systematic review was conducted to evaluate the studies performed in the past 25 years that have reported the prevalence of HBV infection and its associated factors in the Iranian general population (1990-2014). Any study assessing and reporting serum Hbs Ag levels was included in this review. RESULTS After excluding all impertinent studies, 19 eligible studies were included in the analysis. The overall prevalence of HBV was 3% (95% CI 2% to 3%). Its distribution showed that the prevalence of HBV varies in different provinces from 0.87% to 8.86%. The HBV rate was highest in the Golestan (8.86%) and lowest in the Kurdistan (0.87%) provinces. CONCLUSION This study provides some evidence about the prevalence of HBV in Iran. However, the collected data was very heterogenic, even within a single province, which made it hard to estimate a single-point prevalence. High quality studies are needed to find reliable information about HBV prevalence and to decrease the heterogeneity of results in the country.

Diurnal Variation of Essential of the Oil Components of Pycnocycla spinosa Decne. ex Boiss.

BACKGROUND: Pycnocycla spinosa Decne. ex Boiss is an aromatic plant which showed relaxant effects on isolated ileum contractions and antidiarrheal activity. Thirty four components have been extracted from P. spinosa essential oil, of which several major constituents were found to show seasonal variation. OBJECTIVES: The aim of this work is to evaluate the diurnal variation of its oil constituents during specific hours of the day. MATERIALS AND METHODS: The Pycnocycla spinosa samples were collected at different times of the day. The hydro-distilled aerial parts oils of collected P. spinosa were analyzed by GC and GC/MS. RESULTS: Fourteen monoterpenoid and nine sesquiterpenoid components were identified, of which the fluctuating constituents were p-cymene, trans-ß-ocimene, ß-citronellol, citronellyl pentanoate, geranyl isovalerate, α-humulene, caryophyllen oxide, α-cadinol, and α-eudesmol. The content of p-cymene in the essential oil in different daily times varied from 0.16 to 4.19%, and the geranyl isovalerate 7.75 -23.99%. CONCLUSIONS: Essential oils with different qualities can be obtained according to the harvest time of the plant in a day.