The Innervation of Articular Blood Vessels

Despite prevalence of inflammatory joint disease, at present little is known about the factors influencing articular blood flow. It was suggested that joint blood vessels in the dog are innervated by sympathetic efferent nerve fibres whose action is to constrict these vessels (Cobbold and Lewis 1956a). In other studies by Cobbold and Lewis (1956b), it was found that close intra-arterial injection of adrenaline and noradrenaline both produced vasoconstriction, but as to the types of adrenoceptors present on articular blood vessels, less is known. Dick and his colleagues concluded in their study on human that both alpha and beta adrenoceptors were present on knee joint blood vessels (Dick et al 1971). There would appear, however, to be little information known about the nervous control of articular blood vessels either in normal subject or in diseased synovial tissue e. g. rheumatoid arthritis. The object of this research was firstly to assess suitable in-vitro and in-vivo techniques to study knee joint blood vessels along with measurement of blood flow in the knee joint capsule and surrounding tissues such as muscle and bones in both rabbits and cats. Secondly, to perform a more extensive and quantitative investigation in order to characterize the types of receptors that are distributed on articular blood vessels and are important in regulation of blood flow (e. g. adrenoceptors, and purinoceptors), to identify the type(s) of nerves supplying joint blood vessels and their mediator(s) , and whether the endothelium plays a role in regulation of these vessels. Attempts were also made to study changes in nervous control and receptors on these blood vessels that might appear in the acute inflammatory joint disease. Lastly, results obtained in the cat and the rabbit were compared. Relative changes in blood flow were assessed by use of a perfused isolated knee preparation for the in-vitro studies, and both laser Doppler flowmetry and the microspheres technique were employed in the in-vivo experiments. Results from this investigation indicate that 1). Perfusion technique and laser Doppler flowmetry methods provide suitable means of assessing relative changes in articular blood flow in-vitro and in-vivo respectively. 2). Blood vessels in bone around the knee joint of the cat and the rabbit are innervated by presumed sympathetic vasoconstrictor fibres travelling in nerves supplying the joint. 3). Post-synaptic alpha1, alpha2 and pre-synaptic alpha2 adrenoceptors but not beta receptors are present on articular blood vessels. 4). Although P1, P2 purinergic receptors are present on vascular smooth muscle with P2 receptor also present on the endothelial layer, almost all of the data are consistent with the hypothesis that noradrenaline is the main neurotransmitter at knee joint blood vessels and produced vasoconstriction in response to articular nerve stimulation. It is also suggested that noradrenaline released from nerve ending affect mainly alpha1-adrenoceptors. 5). Afferent C fibres in articular nerves produce a dilator response to nerve stimulation and the mediator which is released from their terminals is most likely to be substance P. 6). Acute joint inflammation induced by kaolin increases the adrenoceptor sensitivity and influences those factors which normally regulate articular blood vessel calibre. The mechanisms that cause increase in sensitivity of adrenoceptors and the functional significance of this remain to be investigated. 7). The neurotransmitters released from nerves supplying the knee joint blood vessels and the receptors they act upon appear to be similar in both cat and rabbit. An interesting feature of these results is that, although the popliteal artery divides to give muscular and articular branches in close proximity to each other, the type of receptors on articular blood vessels are closer to that of superficial tissues such as skin than that of blood vessels supplying muscles. Thus, although both skeletal muscle and joints are considered to be deep structures, there is little homogeneity in distribution of receptors and types of innervation, which may reflect the differing function of these two vascular beds

Detection of hepatitis G virus envelope protein E2 antibody in blood donors

SummaryObjectivesThe frequency of hepatitis G virus exposure in blood donors varies between 2.5% in Japan to 24.2% in Poland. Therefore there is a geographic difference in distribution of hepatitis G virus (HGV) in the world. We aimed to determine the frequency of HGV exposure in Iranian blood donors.MethodsBlood samples from 478 Iranian volunteer blood donors were tested. Positive anti-E2 samples were tested for HGV RNA by reverse transcriptase polymerase chain reaction (RT PCR) using primers derived from the NS5A region of the viral genome.ResultsOf the 478 donors enrolled in our study, five (1%) were positive for anti-E2. Only one donor out of a total of three HBsAg-positive donors was co-infected with HGV, but we did not find HGV and HCV co-infection in our subjects. HGV RNA was not observed in the five anti-E2-positive subjects. We did not find HGV viremia and antibody at the same time.ConclusionA low frequency of HGV exposure in blood donors was found in this study. We did not observe co-infection of HGV with HCV in our subjects, supporting the theory that although the parenteral route is the most effective means of transmission, other routes such as sexual contact and intra-familial contact may also play a role in HGV transmission

Angiotensin-converting enzyme genotype and late respiratory complications of mustard gas exposure

<p>Abstract</p> <p>Background</p> <p>Exposure to mustard gas frequently results in long-term respiratory complications. However the factors which drive the development and progression of these complications remain unclear. The Renin Angiotensin System (RAS) has been implicated in lung inflammatory and fibrotic responses. Genetic variation within the gene coding for the Angiotensin Converting Enzyme (ACE), specifically the Insertion/Deletion polymorphism (I/D), is associated with variable levels of ACE and with the severity of several acute and chronic respiratory diseases. We hypothesized that the ACE genotype might influence the severity of late respiratory complications of mustard gas exposure.</p> <p>Methods</p> <p>208 Kurdish patients who had suffered high exposure to mustard gas, as defined by cutaneous lesions at initial assessment, in Sardasht, Iran on June 29 1987, underwent clinical examination, spirometric evaluation and ACE Insertion/Deletion genotyping in September 2005.</p> <p>Results</p> <p>ACE genotype was determined in 207 subjects. As a continuous variable, FEV₁% predicted tended to be higher in association with the D allele 68.03 ± 20.5%, 69.4 ± 21.4% and 74.8 ± 20.1% for II, ID and DD genotypes respectively. Median FEV₁% predicted was 73 and this was taken as a cut off between groups defined as having better or worse lung function. The ACE DD genotype was overrepresented in the better spirometry group (Chi²4.9 p = 0.03). Increasing age at the time of exposure was associated with reduced FEV₁%predicted (p = 0.001), whereas gender was not (p = 0.43).</p> <p>Conclusion</p> <p>The ACE D allele is associated with higher FEV₁% predicted when assessed 18 years after high exposure to mustard gas.</p

Alteration in cardiac uncoupling proteins and eNOS gene expression following high-intensity interval training in favor of increasing mechanical efficiency

Objective(s):High-intensity interval training (HIIT) increases energy expenditure and mechanical energy efficiency. Although both uncoupling proteins (UCPs) and endothelial nitric oxide synthase (eNOS) affect the mechanical efficiency and antioxidant capacity, their effects are inverse. The aim of this study was to determine whether the alterations of cardiac UCP2, UCP3, and eNOS mRNA expression following HIIT are in favor of increased mechanical efficiency or decreased oxidative stress. Materials and Methods: Wistar rats were divided into five groups: control group (n=12), HIIT for an acute bout (AT1), short term HIIT for 3 and 5 sessions (ST3 and ST5), long-term training for 8 weeks (LT) (6 in each group). The rats of the training groups were made to run on a treadmill for 60 min in three stages: 6 min running for warm-up, 7 intervals of 7 min running on treadmill with a slope of 5° to 20° (4 min with an intensity of 80-110% VO2max and 3 min at 50-60% VO2max), and 5-min running for cool-down. The control group did not participate in any exercise program. Rats were sacrificed and the hearts were extracted to analyze the levels of UCP2, UCP3 and eNOS mRNA by RT-PCR. Results:UCP3 expression was increased significantly following an acute training bout. Repeated HIIT for 8 weeks resulted in a significant decrease in UCPs mRNA and a significant increase in eNOS expression in cardiac muscle. Conclusion:This study indicates that Long term HIIT through decreasing UCPs mRNA and increasing eNOS mRNA expression may enhance energy efficiency and physical performance

Effects of low-level lead exposure on blood pressure and function of the rat isolated heart

Objective: Exposure to low levels of lead acetate can induce hypertension in both humans and experimental animals. The exact mechanisms of lead-induced hypertension are not well understood, but its pathogenesis could be explained by the changes in heart rate and contractility. Materials and Methods: In the present study, the effects of exposure to 100 ppm of lead in drinking water (for periods of 4, 8, and 12 weeks) on blood pressure and some physiologic parameters (eg, electrocardiography [ECG], heart rate [HR], cardiac contractility, and coronary flow) of isolated beating rat heart was investigated using the Langendorff isolated heart apparatus. The isolated hearts were perfused with Krebs-Henseleit solution (37°C; pH 7.4; gassed with 95% O 2 + 5% CO 2 ). All data were digitized by a software program for further analysis. Results: The blood pressure in the 8- and 12-week lead-exposed groups was significantly increased as compared to the control group. The ECG showed arrhythmias and conduction abnormalities only in the late phases of exposure (12 weeks). The HR and contractility were significantly higher in the 8- and 12-week lead-treated rats but not in the 4-week group. No significant changes were observed in coronary flow. Conclusion: These results indicate that: 1) low levels of lead exposure do not significantly affect the ECG in the early phase, 2) low levels of lead exposure causes ECG changes in the late phases of exposure, and 3) this level of lead exposure can increase HR and cardiac contractility but has no effect on coronary flow

Cardioprotective Effect of High Intensity Interval Training and Nitric Oxide Metabolites (NO2-, NO3-)

Background: The aim of this study was to investigate the effects of High-Intensity Interval Training (HIIT) on nitric oxide metabolites (NO2-, NO3-) and myocardial infarct size after Ischemia/Reperfusion (I/R) injury in healthy male rats. Methods: A total of 44 Wistar rats were randomly divided into 4 groups including HIIT (n=8), HIIT + IR protocol (n=14), control (n=8), and control + IR (n=14). Each training session of HIIT consisted of 1 hour of exercise in three stages: 6-minute running at 50-60% VO2max for warm-up; 7 intervals of 7-minute running on treadmill with a slope of 50 to 20° (4 minutes with an intensity of 80-100% VO2max and 3 minutes at 50-60% VO2max); and 5-minute running at 50-60% VO2max for cool-down. The control group did not participate in any exercise program. Nitric Oxide (NO) and its metabolites were measured by using Griess reaction test.   Results: The results showed that eight weeks of exercise training exerted a significantly increasing effect on nitrite (8.55 µmol per liter, equivalent to 34.79%), nitrate (62.02 µmol per liter, equivalent to 149.48%), and NOx (66 µmol per liter, equivalent to 98.11%) in the HIIT group compared with the control group. The results showed myocardial infract size (IS) was significantly smaller (23.2%, P<0.001) in the exercise training group compared with the control group. Conclusion: Incremental changes in NO-NO3-, NO2- axis are one of mechanisms through which HIIT program can protect the heart from I/R injury and decrease myocardial infarction

Dietary Virgin Olive Oil Reduces Blood Brain Barrier Permeability, Brain Edema, and Brain Injury in Rats Subjected to Ischemia-Reperfusion

Recent studies suggest that dietary virgin olive oil (VOO) reduces hypoxia-reoxygenation injury in rat brain slices. We sought to extend these observations in an in vivo study of rat cerebral ischemia-reperfusion injury. Four groups, each consisting of 18 Wistar rats, were studied. One group (control) received saline, while three treatment groups received oral VOO (0.25, 0.5, and 0.75 mL/kg/day, respectively). After 30 days, blood lipid profiles were determined, before a 60-min period of middle cerebral artery occlusion (MCAO). After 24-h reperfusion, neurological deficit scores, infarct volume, brain edema, and blood brain barrier permeability were each assessed in subgroups of six animals drawn from each main group. VOO reduced the LDL/HDL ratio in doses of 0.25, 0.5, and 0.75 mL/kg/day in comparison to the control group (p < 0.05), and offered cerebroprotection from ischemia-reperfusion. For controls vs. doses of 0.25 vs. 0.5 vs. 0.75 mL/kg/day, attenuated corrected infarct volumes were 207.82 ± 34.29 vs. 206.41 ± 26.23 vs. 124.21 ± 14.73 vs. 108.46 ± 31.63 mm3; brain water content of the infarcted hemisphere was 82 ±± 0.25 vs. 81.5 ± 0.56 vs. 80.5 ± 0.22 vs. 80.5 ± 0.34%; and blood brain barrier permeability of the infarcted hemisphere was 11.31 ± 2.67 vs. 9.21 ± 2.28 vs. 5.83 ± 1.6 vs. 4.43 ± 0.93 µg/g tissue (p < 0.05 for measures in doses 0.5 and 0.75 mL/kg/day vs. controls). Oral administration of VOO reduces infarct volume, brain edema, blood brain barrier permeability, and improves neurologic deficit scores after transient MCAO in rats

Adherence to the new policy framework of the World Cancer Research Fund International in developing a policy package for the prevention of gastrointestinal cancers in Iran: a Delphi study

BACKGROUND: Gastrointestinal cancers in Iran are among the major non-communicable diseases with a considerable burden on the health system. Changes in lifestyles as well as environmental factors have resulted in the emergence of these cancers. OBJECTIVE: To elicit and quantitatively verify experts\u27 opinions regarding the potential public health impact, feasibility, economic impact, and budgetary impact of gastrointestinal cancer prevention policies in Iran. METHODS: Sixteen experts from Iran were recruited in an email-based, two-round Delphi study. In each round, a questionnaire of policy options for preventing gastrointestinal cancers, which adhered to the new policy framework of the World Cancer Research Fund International, was given to participants. In the first round, experts were asked to provide opinions for and against the policy options. The second round evaluated the policy options for their public health impact, feasibility, economic impact, and budgetary impact. RESULTS: A total of 32 policy options were organized based on three domains: health-enhancing environments, system changes, and behavior change communications. Of the 32 policy options, there were consensus in 31 (96%) and 30 (93%) options for public health impact and feasibility, respectively. On study completion, experts reached a consensus in 29 of 32 (90%) policy options for economic impact; only on 26 (81%) of these policy options did participants reached consensus for budgetary impact. CONCLUSION: Findings indicated that although nearly all policy options reached a consensus for their public health impact, some options are not feasible or do not appear to have an economic rationale for being implemented. Moreover, it is crucial to take into account the inter-sectoral collaboration between health and non-health sectors. Findings from this study can be helpful for health policymakers in identifying support for evidence-informed approaches regarding gastrointestinal cancer prevention

Aggressive hydration with Lactated Ringer′s solution as the prophylactic intervention for postendoscopic retrograde cholangiopancreatography pancreatitis: A randomized controlled double-blind clinical trial

Background: Pancreatitis is a serious complication of endoscopic retrograde cholangiopancreatography (ERCP) and may cause significant morbidity and even death. There is no effective prophylactic intervention for patients with average risk yet. This study aims to investigate preventive effect of aggressive hydration for post-ERCP pancreatitis. Materials and Methods: In a double-blind controlled setting, 150 patient were randomly assigned to receive either aggressive hydration with lactated Ringer′s solution (3 mL/kg/h during ERCP, followed by a 20 mL/kg bolus and 3 mL/kg/h for 8 h after the procedure, n = 75) or standard amount of hydration (1.5 mL/kg/h during and for 8 h after ERCP, n = 75). Patients were observed for volume overload as well as pancreatic pain and serum levels of amylase at baseline and 2, 8, and 24 h after ERCP. Post-ERCP pancreatitis was defined as hyperamylasemia (level of amylase >300) and pancreatic pain during the 24 h follow-up. Hyperamylasemia and pancreatic pain were the secondary end points. Results: Mean age of the patients was 50.8 ± 13.5 years. Most of the patients were female (66%). Pancreatitis developed in 21 patients, including 22.7% of patients receiving standard hydration and 5.3% patients receiving aggressive hydration (P = 0.002). Hyperamylasemia was detected in 44.0% of patients receiving standard hydration and 22.7% of patients aggressive hydration (P = 0.006). The pancreatic pain was reported by 5.3% of patients receiving aggressive hydration and 37.3% of patients receiving standard hydration (P ≤ 0.005). Conclusion: Aggressive hydration with lactated Ringer′s solution may effectively prevent post-ERCP pancreatitis as well as hyperamylasemia and pancreatic pain in patients with average risk

Management of Holding and Evaluating Comprehensive System of Electronic Clinical Reasoning Exams (Sajab) in the Sixth Nationwide Medical Sciences Students Olympiad

Introduction: The Nationwide Medical Sciences Students purpose of the Olympiad is to discover student’s talents and encourage them to study. It seems that holding regional Olympiad exams to select students for the National Olympiad can help us to maintain fairness. The aim of this study is Management of Holding and Evaluating Clinical Reasoning Exams Using a Comprehensive System of Electronic Clinical Reasoning Exams. Methods: Study was carried out in 2013 at the University of Medical Sciences on 750 students, 250 question designers, 37 responsibles. The nationwide universities held regional exams for the Student Olympiad in the area of clinical reasoning on specific dates and times. A quality review of the exams was done to study the strengths and weaknesses and to eliminate shortcomings and problems. Therefore, a researcher created a questionnaire with a reliability of R= 0.86 and validity was confirmed by experts, which was then loaded into the system. The collected data were analyzed using SPSS and descriptive statistics (Percent, Average, standard deviation). Results: The multimedia educational quality of the system, with an average of 69.36 ±22.79, the students and faculty members evaluated as good, with averages of 64.30 ±23.48 and 67.28 ± 22.43, respectively. The quality of the exam was evaluated as excellent by faculty members, with an average of 94.63 ±16.60 and 59.52 ±27.46, by the students. Conclusion: Evaluating the quality of the system’s performance and its ability to assess students will lead to a clarification of its strengths and weaknesses. Finally, result in the creation of a high quality evaluation system