Search results for “Polymerase chain reaction

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13 articles
Ophthalmic Science Open Access

Herpes Zoster Ophthalmicus Presenting with Suspected Orbital Myositis Following Recent Recombinant Zoster Vaccination

Jul 2026 DOI 10.14302/issn.2470-0436.jos-26-6357
Awan MuhammadCorresponding author

Herpes zoster ophthalmicus (HZO) is a manifestation of varicella-zoster virus (VZV) reactivation involving the ophthalmic division of the trigeminal nerve, carrying significant risk of vision-threatening complications. Diplopia in HZO is often attributed to cranial nerve palsy, although orbital myositis remains a rare and underrecognized cause. We present a 79-year-old male who developed right-sided headache, binocular diplopia, and a V1 vesicular rash two weeks after receiving the recombinant zoster vaccine. Examination revealed restriction of extraocular movements without a localizing cranial nerve pattern, raising suspicion for orbital myositis. Neuroimaging was unremarkable, and VZV polymerase chain reaction confirmed the diagnosis of HZO. The patient received antiviral therapy and was discharged in stable condition after three days. This case highlights HZO presenting with suspected orbital myositis in temporal association with vaccination and underscores the need for vigilance for uncommon neuro-ophthalmic manifestations, as early recognition and treatment are essential to prevent vision-threatening complications. Given the patient's advanced age, this case also emphasizes the possibility that age-related immunosenescence may contribute to VZV reactivation and the development of HZO-related ocular complications. Potential therapeutic approaches targeting age-related immune dysfunction are also considered.

A Review on Monkey Pox: Role of One Health Approach Against Monkey Pox

Oct 2023 DOI 10.14302/issn.2641-4538.jphi-23-4622
Geinoro Alleyo TarikuCorresponding author

The Ortho-poxvirus virus, which causes monkey pox, is a member of the Poxviridae genus. It was initially found in primates. In 1970, the Democratic Republic of the Congo reported the first instance of monkey pox. From there, it spread to a number of countries both inside and outside of Africa. There are two genetic varieties of monkey pox, which have been spread to people through respiratory droplets, and touch with objects contaminated by an affected person and consequently is often encountered in work situations. Among the countries with the worst effects are Nigeria and the Democratic Republic of the Congo. Non-human primates, rats, squirrel, and or mice are just a few of the creatures that can become infected by monkey pox. Although the origins of monkey pox infections are unknown, rodents from Africa and non-human primates like monkeys may contain the viruses and infect humans. Monkey pox is more likely to naturally infect rodents. Monkey pox has symptoms and lesions that are difficult to distinguish from smallpox in its clinical manifestations. Fever, chills, migraines, tiredness, tonia, swollen lymph nodes, back pain, and myalgia are some of the clinical symptoms of monkey-pox. A few examples of diagnostic tests include immune-fluorescent antibody assays, enzyme-linked immune-sorbent assays, and real-time polymerase chain reactions. A specialized vaccine that offers complete protection against by them on key-pox virus exists, yet there is no specific therapy for human monkey infection and interaction with the vaccinia virus. Smallpox vaccination can give cross-immunity with partial protection against infection and a reduction in symptom severity. Unfortunately, community health effects in the view of one health approach has not been addressed in vast. Therefore, the objectives of this review paper are to discuss the community health effects of monkey pox and to emphasize the role of one health approach against monkey pox.

Veterinary Healthcare Open Access

Camel Brucellosis in Ethiopia: Seroprevalence and Associated Risk Factor

Oct 2023 DOI 10.14302/issn.2575-1212.jvhc-23-4532
Abda Neja SultanCorresponding author

Camels are a significant source of income for nomadic populations in many developing countries, including Ethiopia. Camels are well adapted to dry and semi-dry regions, providing income, food security, and transportation. However, camel production and productivity are constrained by infectious diseases, such as brucellosis, which is a highly infectious bacterial disease that affects camels and humans worldwide. Brucellosis causes significant economic losses due to abortion, low herd fertility, and decreased milk production. In Ethiopia, the prevalence of camel brucellosis varies depending on factors related to the host, agent, climate, and management system, with a reported prevalence ranging from 0.5% to 11.9%. Accurate diagnosis of camel Brucellosis is essential for herd-based screening of animals. Although culturing the pathogen is the preferred method for diagnosis, serological tests such as Rose-Bengal plate test (RBPT), Enzyme-linked immunosorbent assay (ELISA), and Complement fixation test (CFT) and polymerase chain reaction (PCR) assays have been developed. Implementing effective diagnosis and surveillance systems to control the spread of brucellosis in animals and humans is very important, on top of awareness campaigns, vaccination programs, and suitable laboratory establishment recommended. Continued research is essential to maintain the health and productivity of camel populations, particularly in pastoral areas where camels play a significant role in the livelihood of communities. Therefore, the present paper views the seropositive prevalence and potential risk factors associated with camel brucellosis in Ethiopia.

Veterinary Healthcare Open Access

Detection of carbapenem resistance mechanisms among Avian Pathogenic Escherichia coli (APEC) isolated from broiler chickens

May 2023 DOI 10.14302/issn.2575-1212.jvhc-23-4521
El- shaer AyaCorresponding author

Background The emergence and spread of carbapenem-resistant gram-negative bacteria pose a serious threat to human health. Currently, little is known about the molecular mechanisms underlying carbapenem -resistance and their prevalence among APEC in Egypt. The aim of this study was to detect APEC in clinically diseased broiler chickens collected from broilers farms located at Dakahalia governorates, asses their virulence –associated genes, detect the antimicrobial susceptibility of recovered isolates and to detect genes encoding carbapenemase resistant. Methods A total of 100 organ tissue samples subjected to conventional culture technique for isolation of E. coli. The confirmed E. coli were subjected to disc diffusion method for detection their susceptibility to antimicrobials. Polymerase chain reaction (PCR) was used for detection of APEC virulence genes (hlyA, iutA, ompT, iss, iroN) and six carbapenem- resistant genes namely, blaIMP, blaVIM, blaKPC, blaOXA-48 blaGES and blaNDM,. Results Forty isolates were confirmed to be E. coli  among them, three or more APEC virulence- genes were detected from all isolates. The hlyA gene was detected in 90% (36/40), iroN in 95% (38/40), ompT in 97.5% (39/40), iutA in 92.5% (35/40) and iss was detected in 95% (38/40) of APEC isolates The tested isolates exhibited a remarkable resistance to ampicillin (97.5%), cefuroxime (92.5%), clindamycin (90%), chloramphenicol (62.5%), doxycycline (45%), amikacin (25%) and ciprofloxacin (12.5%). While, the retrieved isolates displayed 100 % sensitivity against imipenem, meropenem, ertapenem, ceftazidime and colistin. Concerning carbapenemase-encoding genes, blaIMP, blaVIM, blaKPC, blaOXA-48, blaGES  couldn’t be detected among the E. coli isolates, while, blaNDM was confirmed in three isolates . Conclusion The detection of NDM as one of the carbapenem resistant genes reveals that the resistant strains are not only capable of infecting humans, but that carbapenams- resistant E. coli (CREC)  has also started to pose a threat to poultry farm and other livestock animals. This may give rise to worries that these food-carrying creatures could infect humans or colonize them.

Veterinary Healthcare Open Access

Cytokine Expression in Peripheral Blood Mononuclear Cell Cultures Obtained from Cattle with Different Stages of Natural Mycobacterium bovis Infection

Dec 2021 DOI 10.14302/issn.2575-1212.jvhc-21-4034
Fernando Díaz-Otero,Corresponding author CENID-Salud Animal e Inocuidad. Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias (INIFAP). Carretera México-Toluca, Km. 15.5, C.P. 05110, Ciudad de México, México.

In bovine tuberculosis (bTB), cellular, humoral, or both types of immune responses have been observed. The purpose of this study was to examine the immune status of tuberculous cows based on the differential cytokine gene expression associated with Th1 (IFN-γ, IL-2), or Th2 (IL-4, IL-10) responses. Twenty-three (23) cows belonging to a dairy herd located in a rural region of the State of Hidalgo, México, were selected for the study. Single Intradermal Comparative Cervical Tuberculin (SICCT) Test, Interferon-Gamma (IFN-γ) Release Assay (BOVIGAM), and Enzyme-Linked Immunosorbent Assay (ELISA) were used for detection of cattle infected by M. bovis. Thirteen cows were positive to all the tests (Group 1); ten cows were positive only to ELISA (Group 2), and the remaining Group (Group 3, control) included cows negative to all the tests. Peripheral blood mononuclear cells (PBMC) from animals were in vitro stimulated by bovin purified protein derivative (PPD), avian PPD, and Concanavalin A (Con A) mitogen for 72h. Changes in the levels of expression of mRNA of the respective cytokines was measured by Reverse Transcription-Polymerase Chain Reaction (RT-PCR) using β-actin gene as internal control. In group 1, PPD bovis and Con A-stimulated cells exhibited high production of IFN-γ, IL-2 and IL-4, but not IL-10. In contrast, PPD avium-stimulated cells displayed a low production of cytokine transcripts. In group 2, cells showed a significant production of IL-10 in response to bovine PPD (P< 0.001). In the control group, a high production of IFN-γ and IL-2 was observed only in Con A-stimulated cells. Post-mortem examinations in animals of group 1 showed slight and medium lesions in lymph nodes, whereas in group 2, the lesions were more extensive. Results indicate differences on gene expression levels of cytokines considered to determine balance in Th1/Th2 response among the evaluated groups. In addition, high levels of antibodies against M. bovis and high IL-10 expression in PBMC together are indicators of progressive bTB when both tuberculin test and IFN-γ assay are negative in tuberculous anergic cattle. Inclusion of serology and IL-10 cytokine expression in in the diagnosis checklist improves detection of infected cattle to help control bovine tuberculosis.

Association of BsmI and ApaI Polymorphisms of the Vitamin D Receptor Gene with Dyslipidemia in Patients with Coronary Artery Disease.

Mar 2020 DOI 10.14302/issn.2374-9431.jbd-20-3195
E.G SergeevaCorresponding author FIRST St. Petersburg state medical University named after academician I. P. Pavlov

Purpose The goals of the present study were to assess the genotypic and allelic distribution of Bsm-I (rs1544410) and Apa-I (rs7975232) polymorphisms of the vitamin D receptor (VDR) gene in coronary artery disease (CAD) patients in comparison to control patients of the same age without CAD and to determine whether these gene variants are associated with dyslipidemia. Materials and Methods Based on a case-control design, 302 hospitalized patients  with CAD and 194 people of comparable age without CAD were enrolled in the study. The BsmI and ApaI polymorphisms of VDR gene were studied using polymerase chain reaction followed by restriction analysis. The allele digested by the restriction enzyme was denoted by a lower letter, whereas that not digested was indicated by a capital letter. Determination of the level of vitamin D and immunoreactive insulin in the blood serum was carried out using the immuno-enzyme method. Results The bb genotype of Bsm-I VDR gene polymorphism was detected more often in patients with CAD than in the comparison group with an increased risk of CAD by 1.52 times (p=0.006, OR=1.52(1.05÷2.2). The level of HDL cholesterol was higher in CAD patients − carriers of BB genotype compared to its level in Bb genotype carriers and bb genotype carriers (1,13±0,05 mmol/l, 1,01±0,03 mmol/l, 1,02±0,03 mmol/l respectively, p<0,05). The level of vitamin D was higher in patients with BB genotype compared to its level in bb genotype carriers (45.12±3.73 nmol / l and 34.16±1.95 nmol/l respectively, p=0.008). The occurrence of a allele of Apa-I VDR gene polymorphism was higher in patients with CAD than in the control group (p=0.02, OR=1.21(0.93÷1.57). HDL cholesterol level was higher in CAD patients - AA genotype carriers compared with carriers of Aa and aa genotypes (1.18±0.08 mmol / l, 1,02±0.02 mmol / l and 1.01±0.03 mmol/l respectively, p<0,05). Immunoreactive insulin level was significantly higher in CAD patients – aa genotype carriers. No differences in LDL cholesterol and triglycerides were found. Vitamin D level was lower in CAD patients - Aa and aa genotype carriers (33,8±33,9 nmol/l ,p=0,02 and 24,7±4,9 nmol/l, p=0,05 respectively in comparison to vitamin D level = 43,3 ±4,2 nmol/l in AA genotype carriers). Conclusion The bb genotype of Bsm-I VDR gene polymorphism is associated with an increased risk of CAD. A carriage of b allele in CAD patients is associated with lower level of vitamin D and HDL cholesterol. A carriage of a allele of Apa-I VDR gene polymorphism in CAD patients is associated with lower level of vitamin D and HDL cholesterol.  

D Allele and DD Genotype of I /D Polymorphism in The ACE Gene in Patients with Hypertension, Stroke And Cancer Prostate In Libreville: A Concern Given The High Frequencies of these Signatures in Gabonese Population

Dec 2019 DOI 10.14302/issn.2326-0793.jpgr-19-3114
Ollomo BenjaminCorresponding author Unité Mixte de Recherches (UMR-BIOMED), Faculté de Médecine, B.P 8507 Libreville, Gabon

Background During the last two decades, the polymorphism of Angiotensin-Converting Enzyme (ACE) gene has been extensively studied among different human populations. In humans, several studies have shown the relationship between this polymorphism and the risk of many serious diseases with a heavy burden of health in developing countries. After analyzing the polymorphism in the population, the present study was also concerned with the investigation of an eventual association between hypertension, stroke, cancer prostate and I/D polymorphism of the ACE gene. Materials and Methods Our study population included 163 Baka (pygmy) and 158 Fang (Bantu) from Gabon to evaluate the polymorphism in the country. Concerning the diseases, we included 105 patients and 120 controls for hypertension, 37 patients stroke matched with 50 controls and 97 patients with prostate cancer were recruited. All participants in the study were genotyped for the ACE I/D polymorphism obtained by polymerase chain reaction amplification on genomic DNA. Results Our analysis showed that the ACE D allele DD genotype frequencies were highest of all the data so far in human populations. We obtained a frequency of 0.138 for I allele and 0.862 for D allele among pygmy and the frequencies of 0.313 and 0.687 respectively for the I and D alleles. This difference was significant (p<0.05). In patients, we revealed the predominance of D allele and DD genotype for hypertension (0.27 for I allele and 0.73 for D allele), for stroke (0.15 for I allele and 0.85 for D allele) and 83% of individuals with cancer prostate carry the D allele. D allele and DD genotype are associated with risk to hypertension whereas allele I seem protective at the occurrence of stroke (p<0.05 between healthy and controls). Conclusion We show that the D allele and DD genotype were higher in this population. Also theses two signatures may be associated at genetic risk of hypertension, stroke and prostate cancer in this country deprived of human resources for quality care of many patients.

L162v Polymorphism of Par-Α Gene, A603g Polymorphism of Tissue Factor Gene and Risk of Coronary Heart Disease in Russian Population

Jun 2019 DOI 10.14302/issn.2374-9431.jbd-19-2788
Sergeeva E.G.Corresponding author First Pavlov State Medical University of St. Petersburg

Purpose The goal of this study is to determine the association of L162V polymorphism of PPAR-alpha gene, A603G polymorphism of tissue factor gene and the risk of coronary heart disease development in Russian population.   Materials and Methods A clinical and genetic study of 414 patients with CHD and 220 people of comparable age without CHD which amounted to a control group was performed. L162L and L162V genotypes of L162V polymorphism of PPAR-α gene, A603A, A603G and G603G genotypes of A603G polymorphism of tissue factor gene were determined by polymerase chain reaction followed by restriction analysis. Results A carriage of L162V genotype and V allele of PPAR-α gene was associated with an increase risk of CHD in 2,13 times (L162V genotype) and in 2,21 times (V allele), with an increase in risk of CHD before the age of 45 years in 4,68 times (L162V genotype) and in 3,88 times (V allele). Significantly higher in patients with CHD compared with the general population and in patients with a carriage of G603G genotype and G allele of tissue factor gene was associated with the increase of CHD risk in 2,68 times (G603G genotype) and in 4,37 times (G allele), occurred more frequently in patients with debut of disease at age of 45 years and younger. The level of tissue factor was significantly higher in patients with CHD – carriers G603G genotype compared with carriers A603A genotype (217,9±15,2 pg/ml and 152,6±30,4 pg/ml, respectively, p=0,04). A carriage of the combination of L162V and G603G genotypes was associated with an increased risk of CHD in 3,04 times. Conclusion A carriage of V allele of L162V polymorphism of PPAR-α gene and G allele of A603G polymorphism of tissue factor gene, as well as their pair combination are associated with an increased CHD risk, especially at age 45 years or less.

Hepatic Tuberculosis of Pseudotumor Form

Mar 2018 DOI 10.14302/issn.2578-2371.jslr-18-1994
Meriam SabbahCorresponding author Department of gastroenterology, Habib Thameur Hospital, Tunis, Tunisia.

Tuberculosis involving the liver in the absence of active pulmonary tuberculosis is very rare. The inflammatory pseudotumoral form is an entity difficult to diagnose. We report a case of an inflammatory pseudotumor of the liver due to tuberculosis, who didn’t underwent hepatectomy because of the size of the tumor. The diagnosis of tuberculosis was made on biopsy and Polymerase Chain Reaction (PCR).

Study of VCAM-1 Gene Expression in Normal and Tumoral Tissues in Patients with Colorectal Cancer

Nov 2017 DOI 10.14302/issn.2576-6694.jbbs-17-1744
Mahjoubi FrouzandehCorresponding author Department of Clinical Genetics, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran

Aim: Colorectal cancer is one of the most commonly diagnosed cancers in the world. Cell adhesion molecules play an important role in the progression of various cancers. It has been shown that the high level expression of some Cell adhesion molecule could be a new diagnostic factor for several cancers. Vascular cell adhesion molecule 1(VCAM1) is a cell surface glycoprotein that is expressed in the endothelium activated by cytokine. Generally, VCAM-1 expression level is very poor in normal adult tissue endothelial cells. According to the above explanation, this study was conducted to investigate the expression of VCAM-1 in tumoral tissues and adjacent normal tissues in Iranian colorectal cancer patients to its relation with clinicopathological Features in patients with cancer. Methods: In this study, 60 tumoral tissues and 39 adjacent normal tumor tissues were evaluated using reverse transcription-polymerase chain reaction (RT-PCR) technique. Conclusion: A significant correlation was found between VCAM-1 expression level and the stage, lymph nodes involvement, tumor progression factor of cancer and sex. Interestingly, VCAM-1 expression not observed in tumors with stage0. No association was seen between VCAM-1 expression and other clinical features such as age, size of the tumor, metastasis and the number of lymph nodes. These findings suggest that VCAM-1 expression level may reflected disease progression and elevation in VCAM-1 has prognostic significance in patients with colorectal carcinoma.

Association of Epstein-Barr Virus with Gastric Carcinoma among Sudanese Patients

Oct 2016 DOI 10.14302/issn.2572-3030.jcgb-16-1190
omer IbtihalCorresponding author Department of Medical Microbiology, Faculty of Medical Laboratory Sciences, University of Khartoum, Sudan

Background: Gastric cancer (GC) ranks as the fourth most common cancer and the second leading cause of cancer deaths worldwide. Epstein-Barr virus is a well-known oncogenic virus, it is responsible for 10% of gastric carcinomas across the world. The aim of study was to determine the prevalence of EBV associated with GC in Sudanese patients. Method: Fifty Paraffin embedded blocks of gastric biopsy specimens diagnosed as gastric carcinoma were collected from Soba university hospital and Ribat teaching hospital, Khartoum, Sudan. DNA was extracted from the paraffin-embedded tissue, and then Epstein-Barr virus gene was detected by polymerase chain reaction (PCR). Result: Among the gastric biopsy specimens 27 (54.0%) were of male and 23(46.0%) were of female. Eleven EBV positive samples were found in gastric carcinomas (22.0%), 8 (72.7%) were of male and 3(27.2%) were of female. The mean age of the patients was 56 years, the most positive cases were between 50-59 years old, and (10%) of them are alive in Khartoum. Conclusions: There exists an association between EBV and gastric carcinoma in some Sudanese patients.

DNA And RNA Research Open Access

Investigations of Molecular Evolutionary Mechanisms in Partially Sequenced Heat Shock Protein70 Homologue-Coding Gene of Olive Leaf Yellowing-Associated Virus Isolates from Tunisia

Feb 2016 DOI 10.14302/issn.2575-7881.jdrr-15-849
BOULILA MoncefCorresponding author Professor, Université de Sfax- Institut de l’Olivier- B.P. 14, 4061 Sousse Ibn Khaldoun, Tunisia.

Reverse Transcription Polymerase Chain Reaction (RT-PCR) using new designed primers pair for Heat Shock Protein70 homologue (HSP70h) of Olive leaf yellowing-associated virus revealed 667 amplified product of 10 olive accessions collected from various olive-growing regions in Tunisia. Amplicons were cloned and sequenced. The sequences were deposited in the international databases. Pairwise sequence comparisons among 10 Tunisian isolates along with a reference sequence (AJ440010) extracted from GenBank revealed a nucleotide identity of 86.06-99.40 and an amino acid similarity of 91.89-99.55. Sequence multiple alignments were searched for evidence of recombination using three methods, ie. Differences of Sums of Squares (DSS) implemented in TOPALi v2.5 software and Single Breakpoint (SBP) along with GARD, a genetic algorithm, both incorporated in HyPhy package. All used methods pointed out the presence of putative breaking points in partially sequenced HSP70h-coding gene. Since failing to account for recombination can mislead the phylogeny inference and can elevate the false positive error rate in positive selection assessment, the use of GARD resulted in the reconstruction of different phylogenies on the left as well as on the right sides of putative recombination breaking points, and the 11 accessions were distributed into at least three clusters compared to MEGA6 software which delineated only two clades. Nonetheless, by dividing the aligned sequences at breakpoints into separate sequence sets, MEGA6 delineated a clustering pattern different from the former two. As a result, recombination reshuffled the affiliation of the different accessions to the clusters. Analysis of selection pressures exerted on HSP70h encoded protein using different models (SLAC, IFEL, FEL, REL, PARRIS, FUBAR, MEME, GA Branch, and PRIME) taking into account recombination, and implemented in HyPhy package, revealed that it underwent predominantly purifying selection as confirmed by Tajima’s D, Fu and Li’s D and F tests, and SNAP algorithm. However, a few sites were also under positive selection as assessed by various models such as FEL, IFEL, REL, MEME, and PRIME.

Role of Helicobacter Pylori in Nasal Polyp Formation: A Case-Control Study in Tehran, Iran

Jan 2016 DOI 10.14302/issn.2379-8572.joa-15-814
Farhadi MohammadCorresponding author ENT –Head & Neck surgery Research Center, Iran University of Medical Sciences, Tehran, Iran

Background and Objective: The etiological factors for nasal polyps include infection, inflammation or an imbalance of a metabolic pathway. This study was designed to compare serum Helicobacter pyloriantibodies and H. pylori–DNAs between cases of nasal polyp and controls (nasal fracture). Patients and Methods: This case control study was carried out in ENT Department of Rasul Hospital in Tehran (2007-2008), upon nasal polyp tissues in 62 cases and inferior nasal turbinate mucosa in 25 controls. H. pylori–DNAs were searched by qualitative polymerase chain reaction (PCR) and serum specific H. pylori antibodies (ELISA IgG and IgA). Comparative tests were performed for the 2 groups, and P value < 0.05 was considered as statistically significant. Results: The mean age of cases and controls were 37.5 ± 13.7 and 31 ± 11.5 years, respectively. H. pylori–DNA was found in 32.3% (20/62) of the cases and 4% (1/25) of the controls (P value = 0.005). Serum H. pylori antibody (IgA) was found in 14.5% (9/62) of the cases and 4% (1/25) of the controls (P value = 0.27). However, previous immunity (IgG) was higher in 71% of the cases and 32% of the controls (P = 0.001). Conclusion: H. pylori infection may play a key role in the formation of nasal polyps. We recommend the PCR as the best method of searching for H. pylori infection. However, from the data obtained in this investigation it could not be determined whether or not H. pylori play a pathogenic role. Long-term antibiotics treatment in cases with nasal polyp, especially in cases with severe chronic rhinosinusitis where patients do not respond to surgery or steroids, may be useful. More randomized controlled trial (RCT) studies are necessary to validate the role of H. pylori infection in nasal polyp and the effect of antibiotics for eradication of H. pylori infection.

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