Assembly of high molecular weight kininogen and activation of prekallikrein on cell matrix

Investigations determined if extracellular matrix of endothelial cells (EC) is a platform for HK assembly and PK activation. In buffers containing bovine serum albumin, biotin-HK binding to ECV304 cells or their matrix requires > or = 50 microM added Zn2+. Ortho-phenanthroline or a HK domain 5 peptide blocks HK binding. Binding to umbilical vein EC or matrix, but not ECV304 cells or matrix, is mediated by cytokeratin 1. Biotin-HK binds to ECV304 cells or matrix with a Kd of 15.8 or 9.0 nM and a Bmax of 2.6 x 10(7) or 2.4 x 10(7) sites/cell, respectively. PK activation on ECV304 cells or matrix is blocked by antipain or SBTI and corn trypsin inhibitor partially inhibits kallikrein formation. PK activation occurs on ECV304 cells or matrix prepared without serum or in human factor XII deficient serum, indicating that the PK activator is not factor XIIa. EC matrix promotes plasminogen activation after the assembly of HK, PK and pro-urokinase. These studies indicate that matrix of various EC has the ability to assemble HK allowing for PK activation and subsequent activities.     

Factors associated with contraceptive use in Tehran, Iran.

OBJECTIVES: In spite of the government's efforts, the prevalence of contraceptive use in Iran is only 55.4%. Health concerns, side effects, failure of the methods and some demographic issues, among which education, age, and number of daughters, have a great influence on the enforcement of contraceptive measures. The aim of the present study was to identify factors affecting contraceptive use in Iran. METHODS: Data from the project 'The study of contraceptive practice in Tehran, 1999-2000' were analyzed with regard to the factors associated with contraceptive use by Iranian couples. A total of 4042 women at reproductive ages who had delivered in one of the 12 teaching hospitals of Tehran and had at least one child that lived for at least 24 hours after birth, were interviewed using a questionnaire that gathered information about their socio-demographic status, fertility history, and other characteristics. RESULTS: Using a multinomial logistic regression, it was found that the woman's age, her own or her husband's level of education, previous awareness about contraceptive methods, number of abortions, and number of sons and daughters were factors that were significantly associated with contraceptive use. CONCLUSIONS: A number of factors affect the application of contraceptive measures. It is essential that health policy makers be aware of these to promote contraception and population control.     

Quality of survival in histiocytosis X: A southwest oncology group study

Sixty children survived for five years after the diagnosis of histiocytosis X. Serious disabilities were seen in 50% of children whose disease involved soft tissue and bone. Late deaths from pulmonary failure were associated with opportunistic infections in two cases. Future treatment approaches must weigh the risks of therapy-related complications against the probability of significant disability if the disease continues for many years.     

Delayed Neurological Complications of Sulphur Mustard and Tabun Poisoning in 43 Iranian Veterans

Delayed neurotoxic complications of chemical warfare agents (CWA), such as sulphur mustard (SM) and tabun, in human beings have not been reported in detail. We thus aimed to investigate possible neurotoxic complications of these agents in Iranian veterans 22–27 years after exposure. After co‐ordination with the veteran foundation and obtaining the approval of the medical research ethics committee, 43 Iranian veterans with late complications of CWA exposure during the Iran–Iraq conflict were studied after obtaining signed written informed consent. Demographic and clinical findings were recorded on pre‐designed forms. Neurological examination was performed by a neurologist. Routine biochemical tests were performed for all the patients. Electromyography (EMG), nerve conduction velocity (NCV) and electroencephalography (EEG) were carried out as clinically indicated. The majority of the patients (38) had been exposed to SM and only five patients to tabun. Hyperaesthesia was the most objective finding (72.1%). Fatigue (93%), paraesthesia (88.3%) and headache (83.7%) were the most common subjective findings in the patients. Sensory nerve impairments, including paraesthesia (88.3%), hyperaesthesia (72.1%) and hypoesthesia (11.6%), were the most common observed clinical complications. EMG and NCV were impaired in seven patients (16.3%) who were all SM‐exposed patients but did not show any significant correlation with organ complications. EEG was negative even in the seized patients. Cholesterol, LDL and triglyceride levels were significantly above the normal ranges. Late neurological complications of CWA, particularly SM poisoning, are considerable even after three decades of exposure and require medical attention.     

Bone density in patients with chondromalacia patella

Chondromalacia of the patella is the most common cause of anterior knee pain in young women. The etiology of the disease is not well-understood but the initial lesion is a disorganization of collagenous structures. Since the disease is proposed to be due to generalized constitutional disturbance, we postulated that bony structures could also be involved. To investigate this hypothesis we measured the bone density of 286 patients with the diagnosis of chondromalacia of the patella during a 4-year period using dual energy X-ray absorptiometry (DXA) method. We found a significant number of patients having low bone densities. This problem was more pronounced in men and in younger age groups. We suggest base-line bone density evaluation in all patients, treatment of osteopenia or osteoporosis in select patients and regular follow-ups using DXA.     

Genetic diversity and distribution of tomato-infecting begomoviruses in Iran

The incidence and severity of tomato leaf curl disease (TLCD) is increasing worldwide. Here we assess the diversity and distribution within tomato producing areas of Iran of begomoviruses that cause this disease. Tomato with typical TLCD symptoms and asymptomatic weeds were collected in 2005 and 2006 and tested for the presence of begomovirus DNA using polymerase chain reaction (PCR). Analysis of cloned and sequenced PCR products revealed that both mono- and bipartite begomoviruses are associated with TLCD in Iran. Furthermore, our results confirmed the symptomless infection with mono- and bipartite begomoviruses of two weed species, Chrozophora hierosolymitana Spreng (Euphobiaceae) and Herniaria sp. (Caryophyllaceae). Eighteen Iranian begomovirus isolates were classified into two major groups and two or three subgroups according to the 5′-proximal 200 nucleotides of the coat protein (CP) gene or the N-terminal 600 nucleotides of the Rep gene. Whereas most of the monopartite isolates showed closest similarity to tomato yellow leaf curl virus-Gezira (TYLCV-Ge), the three bipartite isolates were most similar to Tomato leaf curl New Delhi virus (ToLCNDV). Mixed mono- and a bipartite begomovirus infections were detected in both tomato and C. hierosolymitana. Our results indicate that the tomato producing areas in central, southern, and southeastern Iran are threatened by begomoviruses originating from both the Mediterranean basin and the Indian subcontinent.     

Regeneration of sciatic nerve crush injury by a hydroxyapatite nanoparticle-containing collagen type I hydrogel

The current study aimed to enhance the efficacy of peripheral nerve regeneration using a hydroxyapatite nanoparticle-containing collagen type I hydrogel. A solution of type I collagen, extracted from the rat tails, was incorporated with hydroxyapatite nanoparticles (with the average diameter of ~212 nm) and crosslinked with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) to prepare the hydrogel. The Schwann cell cultivation on the prepared hydrogel demonstrated a significantly higher cell proliferation than the tissue culture plate, as positive control, after 48 h (n = 3, P < 0.005) and 72 h (n = 3, P < 0.01). For in vivo evaluation, the prepared hydrogel was administrated on the sciatic nerve crush injury in Wistar rats. Four groups were studied: negative control (with injury but without interventions), positive control (without injury), collagen hydrogel and hydroxyapatite nanoparticle-containing collagen hydrogel. After 12 weeks, the administration of hydroxyapatite nanoparticle-containing collagen significantly (n = 4, P < 0.005) enhanced the functional behavior of the rats compared with the collagen hydrogel and negative control groups as evidenced by the sciatic functional index, hot plate latency and compound muscle action potential amplitude measurements. The overall results demonstrated the applicability of the produced hydrogel for the regeneration of peripheral nerve injuries.     

Electroencephalogram complexity analysis in children with attention-deficit/hyperactivity disorder during a visual cognitive task

Objective: The aim of this study was to investigate electroencephalogram (EEG) dynamics using complexity analysis in children with attention-deficit/hyperactivity disorder (ADHD) compared with healthy control children when performing a cognitive task. Method: Thirty 7–12-year-old children meeting Diagnostic and Statistical Manual of Mental Disorders–Fifth Edition (DSM–5) criteria for ADHD and 30 healthy control children underwent an EEG evaluation during a cognitive task, and Lempel–Ziv complexity (LZC) values were computed. There were no significant differences between ADHD and control groups on age and gender. Results: The mean LZC of the ADHD children was significantly larger than healthy children over the right anterior and right posterior regions during the cognitive performance. In the ADHD group, complexity of the right hemisphere was higher than that of the left hemisphere, but the complexity of the left hemisphere was higher than that of the right hemisphere in the normal group. Conclusion: Although fronto-striatal dysfunction is considered conclusive evidence for the pathophysiology of ADHD, our arithmetic mental task has provided evidence of structural and functional changes in the posterior regions and probably cerebellum in ADHD.