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

Hepatitis E virus infection in hemodialysis patients: A seroepidemiological survey in Iran

BACKGROUND: The hepatitis E virus (HEV) has a global distribution and is known to have caused large waterborne epidemics of icteric hepatitis. Transmission is generally via the fecal-oral route. Some reports have suggested parenteral transmission of HEV. Anti-HEV prevalence data among chronic hemodialysis (HD) patients are few and give conflicting results. METHODS: This cross-sectional study was conducted in August of 2004. We tested 324 chronic HD patients attending three different units in the city of Tabriz, northwestern part of Iran, for anti-HEV antibody. A specific solid- phase enzyme-linked immunoassay (Diapro, Italy) was used. RESULTS: The overall seroprevalence of hepatitis E was 7.4 %(95% CI: 4.6%–10.6%). The prevalence rate of HBV and HCV infection were 4.6% (95% CI: 2.3%–6.9%) and 20.4% (95% CI: 16%–24.8%), respectively. No significant association was found between anti-HEV positivity and age, sex, duration of hemodialysis, positivity for hepatitis B or C virus infection markers and history of transfusion. CONCLUSION: We observed high anti-HEV antibody prevalence; there was no association between HEV and blood borne infections (HBV, HCV, and HIV) in our HD patients. This is the first report concerning seroepidemiology of HEV infection in a large group of chronic HD individuals in Iran

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

Fertility disorder associated with celiac disease in males and females: fact or fiction?

Abstract Aim: The association between celiac disease and infertility is controversial in the literature

A comparison of oral omeprazole and intravenous cimetidine in reducing complications of duodenal peptic ulcer

BACKGROUND: Gastrointestinal bleeding is a common problem and its most common etiology is peptic ulcer disease. Ulcer rebleeding is considered a perilous complication for patients. To reduce the rate of rebleeding and to fasten the improvement of patients' general conditions, most emergency departments in Iran use H2-blockers before endoscopic procedures (i.e. intravenous omeprazole is not available in Iran). The aim of this study was to compare therapeutic effects of oral omeprazole and intravenous cimetidine on reducing rebleeding rates, duration of hospitalization, and the need for blood transfusion in duodenal ulcer patients. METHODS: In this clinical trial, 80 patients with upper gastrointestinal bleeding due to duodenal peptic ulcer and endoscopic evidence of rebleeding referring to emergency departments of Imam and Sina hospitals in Tabriz, Iran were randomly assigned to two equal groups; one was treated with intravenous cimetidine 800 mg per day and the other, with 40 mg oral omeprazole per day. RESULTS: No statistically significant difference was found between cimetidine and omeprazole groups in regards to sex, age, alcohol consumption, cigarette smoking, NSAID consumption, endoscopic evidence of rebleeding, mean hemoglobin and mean BUN levels on admission, duration of hospitalization and the mean time of rebleeding. However, the need for blood transfusion was much lower in omeprazole than in cimetidine group (mean: 1.68 versus 3.58 units, respectively; p < 0.003). Moreover, rebleeding rate was significantly lower in omeprazole group (15%) than in cimetidine group (50%) (p < 0.001). CONCLUSION: This study demonstrated that oral omeprazole significantly excels intravenous cimetidine in reducing the need for blood transfusion and lowering rebleeding rates in patients with upper gastrointestinal bleeding. Though not statistically significant (p = 0.074), shorter periods of hospitalization were found for omeprazole group which merits consideration for cost minimization

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