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This computational study deals with the mechanism of spontaneous initiation in thermal polymerization of alkyl acrylates (e.g., methyl, ethyl, and n-butyl acrylate). The mechanism is presently still unknown. Density-functional theory (DFT) and Møller-Plesset (MP2) calculations are used to explore the Flory and Mayo mechanisms of self-initiation in methyl acrylate. On the singlet surface, a low-barrier, concerted [4 + 2] Diels-Alder mechanism for the formation of a dihydropyran adduct (DA) and a high-barrier nonconcerted [2 + 2] diradical ((*)M(2s)(*)) mechanism for the formation of dimethyl cyclobutane-1,2-dicarboxylate (DCD) were found using B3LYP/6-31G*. Several levels of theory were used to validate the transition states, and the pathways for the DA and DCD formations on the singlet surface were determined using intrinsic reaction coordinate (IRC) calculations. On the triplet surface, a triplet diradical intermediate ((*)M(2t)(*)) was identified that is structurally similar to (*)M(2s)(*) but lower in energy. The spin-orbit coupling constant for crossover of the diradical from singlet to triplet surface was calculated. Monoradical generation from the two intermediates, DA and (*)M(2t)(*) via hydrogen transfer to or from a third methyl acrylate was studied. It was found that generation of two monoradical species was possible from (*)M(2t)(*) and is proposed as a likely explanation for experimentally observed spontaneous-initiation.

This study was conducted to determine the cardiovascular risk factors among 327 Iranian males with bilateral lower limb amputation.The average age at the time of amputation and at the time of the study was 20.6 (SD = 5.4) and 42 years (SD = 6.3), respectively. Below both knees was the most common level of amputation (37.6%). About 95.4% had at least one modifiable risk factor. Prevalence of risk factors included: hyperglycemia 13.1%, systolic hypertension 18.9%, diastolic hypertension 25.6%, abdominal obesity 82.5%, high total cholesterol 36.7%, low HDL 25.9%, high LDL 24.7%, high triglycerides 32.1%, and smoking 31.8%. The most common risk factor was abdominal obesity. Prevalence of coronary artery disease was similar to the general Iranian population but prevalence of risk factors was higher significantly. The majority of the cases seem to be susceptible to cardiovascular disease in near future. Some strategies are needed as a primary prevention to reduce the risk of cardiovascular disease.

Background: Sulfur mustard (SM), a chemical weapon used widely during World War I and against Iranians during the Iran-Iraq War of the 1980s, causes massive inflammatory tissue damage in the immediate post-exposure period, resulting in debilitating chronic disease in years to decades following contact with the agent. These syndromes most often are pathologies of the lungs, eyes, and skin, the primary target organs of SM. Typically, they are characterized by severe and increasingly painful inflammation, often accompanied by fibrosis and constriction of the anatomic channels needed for normal life, such as the small airways of the lungs and, in the present report, the urethra., Methods: The present case study is a 43-year-old man with a history of heavy SM exposure to the groin in 1984., Result: Within 1 year after exposure, the patient was found to have developed meatal stricture, occlusion of the external urethral meatus, and difficulty in urination. Two years post-exposure, he underwent ventral meatotomy and meatoplasty., Conclusion: This case presents a unique example of the latent effects of SM exposure to the groin, and will be of value in the prevention of similar injury and complications to persons at risk of SM exposure in the future.

Unlabelled: Sulfur mustard (SM), also known as mustard gas, is an alkylating compound used as a chemical weapon in World War I and by Iraqi forces against Iranians and indigenous Iraqi Kurds during the Iran-Iraq War of the 1980s. Although SM is a proven carcinogen there are conflicting views regarding the carcinogenicity of a single exposure. The present study characterizes lung cancers formed in mustard gas victims from the Iran-Iraq War., Methods and Materials: Demographic information and tumor specimens were collected from 20 Iranian male lung cancer patients with single high-dose SM exposures during the Iran-Iraq War. Formalin-fixed, paraffin-embedded lung cancers were analyzed by immunohistochemistry for p53 protein. In addition, DNA was extracted from the tissues, PCR amplified and sequenced to identify mutations in the p53 and KRAS genes associated with SM exposure., Results: A relatively early age of lung cancer onset (ranging from 28 to 73 with a mean of 48) in mustard gas victims, particularly those in the non-smoking population (mean age of 40.7), may be an indication of a unique etiology for these cancers. Seven of the 20 patients developed lung cancer before the age of 40. Five of 16 cancers from which DNA sequence data was obtainable provided information on eight p53 mutations (within exons 5-8). These mutations were predominately G to A transitions; a mutation consistent with the DNA lesion caused by SM. Two of the lung cancers had multiple p53 point mutations, similar to results obtained from factory workers chronically exposed to mustard agent. No mutations were detected in the KRAS gene., Discussion: The distinguishing characteristics of lung carcinogenesis in these mustard gas victims suggest that a single exposure may increase the risk of lung cancer development in some individuals.

To evaluate the prevalence of neuroma in bilateral upper limb amputees and investigate the effect of level of amputation on their pain, 86 patients with bilateral upper limb amputation were thoroughly examined by an orthopedic surgeon. Of 172 bilateral amputated upper limbs (86 victims of war) 17.1+/-6.1 years after injury, physical examination revealed that 26.2% had moderate to severe stump pain and clinical signs suggestive of neuroma. Statistical analysis showed no relation between level of amputation, prosthesis usage, and occurrence of neuroma. Although high occurrence of neuroma among traumatic bilateral upper limb amputation had no significant effects on wearing prosthesis, its treatment can deeply influence alleviation of their pain and subsequently their quality of life.

Background: In view of lack of comprehensive data on landmine casualties that lead to amputation in Iran, we conducted this study to determine the pattern and demographic features of landmine explosions that result in amputation of the victims., Methods: To define the pattern of landmine- and unexploded ordinances-induced amputations and to understand the most common types of underlying activities at the time of the blast, a retrospective study was conducted among the victims in 5 western provinces of Iran, West Azerbaijan, Kermanshah, Kurdistan, Ilam, and Khuzestan between 1988 and 2003., Results: Of a total of 3713 victims, 1499 had undergone amputations. The mean age of the victims at the time of accident was 23 years; 92% of the victims were male, 48.4% of them were of very poor education and all were civilians. Below knee amputation was the commonest type of amputation., Conclusion: The occurrence of lower limb amputations from landmine injuries in Iran is a significant burden on the healthcare system; rendering allocation of more resources to provide preventative and rehabilitation measures is therefore a must.

Approximately 34,000 Iranians known to have sustained mustard agent exposure during the Iran-Iraq war of 1980-1988 and survived over a decade afterwards were screened for distribution of the most commonly occurring medical problems. In order of greatest incidence, these include lesions of the lungs (42.5%), eyes (39.3%), and skin (24.5%). Within each subpopulation, patients were ranked according to severity of lesions. Twenty-three percent to 37% of patients exhibited at least mild coverage, with 1.5% to 4.5% classed as moderate, and a much smaller population (0.023-1.0%) of the 34,000 patients exhibiting extensive (severe) lesional coverage. These results provide a comprehensive overview of the medical problem most common among mustard victims and could serve as a predictor of the likely impact of these weapons on health status of populations exposed to them during ongoing military conflicts.

Purpose: A major component of bladder surface mucin is a glycoprotein GP51 (molecular weight 51 kD.). GP51, which has previously been isolated from rabbit mucosa, appears to function as part of the defense mechanism in an in vivo infection model. GP51 coats the epithelium and is secreted into the urine, as detected by immunohistochemical testing and enzyme-linked immunosorbent assay (ELISA). Increased urinary GP51 occurs during urinary tract infection. To elucidate the role of GP51 as a component of the primary defense mechanism we studied interactions with uropathogenic bacterial isolates and urine from symptomatic patients with urinary tract infection., Materials and Methods: ELISA was performed to demonstrate the binding of GP51 and various uropathogens. Immunochemical studies were done using monoclonal antibodies to GP51 to determine the interaction of GP51 with certain uropathogenic isolates, including Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa, Serratia marcescens, Staphylococcus aureus, S. epidermidis and Streptococcus faecalis. Infected urinary sediments and uropathogenic bacterial cultures were examined by immunocytochemical testing to localize GP51. Antigen inhibition ELISA was done to quantitate urinary GP51 in the urine of 17 normal controls and 19 patients with urinary tract infection., Results: ELISA revealed that GP51 binds to a wide spectrum of gram-positive and gram-negative uropathogens in semiquantitative fashion. Immunochemical methods confirmed that purified GP51 binds to bacteria, encapsulating and aggregating the bacteria. Clinical specimens showed GP51 localized to bacteria and uroepithelial cells. We observed a significant increase in urinary GP51 in urinary tract infection compared to uninfected urine (p = 0.0003)., Conclusions: These studies suggest that GP51, a component of bladder mucin, may be a strategic factor in the primary defense mechanism of the bladder.

Fourteen consecutive patients underwent placement of a multicomponent penile prosthesis under regional anesthesia using a pudendal nerve block. Results demonstrated the need for minimal administration of intraoperative narcotics, no major fluctuations in the blood pressure or pulse rate during intraoperative monitoring, and only 1 of 14 patients was converted to general anesthesia. Postoperatively, our results show that there was no urinary retention or cardiac side effects, adequate postoperative analgesia was obtained, and 13 of the 14 patients were discharged within 24 hours. This method was safe, effective, easily performed, and does not carry the associated morbidity of general or spinal anesthesia.

This paper concerns real-time, multi-rate, nonlinear state and parameter estimation in a pilot-scale biochemical reactor in which cultivation of mouse-mouse hybridoma cells takes place. A multi-rate estimator is designed and implemented to estimate specific growth rate and concentrations of viable cells, total cells, glucose, glutamine, and monoclonal antibodies (MAb) in the reactor. These are estimated from frequent measurement (inferred values) of oxygen uptake rate (OUR) and infrequent and delayed measurements of the concentrations of viable cells, total cells, glucose, glutamine, and MAb. The infrequent measurements are available every 2 to 17 h with a time delay of 0.08 to 2.00 h, and OUR is inferred from dissolved oxygen concentration measurements that are available very 0.17 h. For each of the process variables, its infrequent measurement data and the profile of its estimate are presented to show the performance of the multi-rate estimator., (Copyright 1999 John Wiley & Sons, Inc.)

With improvements in technology, we continue to seek new surgical techniques to approach old surgical issues. Antegrade percutaneous endopyelotomy has become the most common first-line approach to treatment of ureteropelvic junction obstruction, however, it is now possible to treat this condition successfully through a retrograde ureteroscopic approach. By combining the latest small ureteroscopes with the technology of endoluminal ultrasound, it is possible to treat this disease in a single setting without the complications of ureteral strictures or significant postoperative hemorrhage, thereby eliminating the need for a nephrostomy tube and dramatically reducing the morbidity of the procedure.

Cytoskeletal agents have been demonstrated to inhibit stimulated motility and substrate adherence by the human tumor cell line, A2058. cis-tubulozole, taxol, and cytochalasin D were tested for their effects on chemotaxis in response to a tumor cytokine, autocrine motility factor, and on adherence to several substrata: laminin- and gelatin-coated dishes as well as tissue culture plastic. Cytochalasin D, which inhibits microfilament polymerization, abolished stimulated motility. Taxol, which stabilizes microtubules, decreased stimulated motility to a greater degree than cis-tubulozole, which inhibits microtubular polymerization. In contrast, cis-tubulozole had the greatest inhibitory effect on adherence with a gelatin substratum more affected (100% inhibition) than tissue culture plastic (90%) or laminin substratum (52%). Taxol affected adherence in the same order but less than cis-tubulozole. Cytochalasin D had no significant effect on adherence to laminin with moderate inhibition of adherence to tissue culture plastic or gelatin. These data suggest that, in these tumor cells, microfilaments are more crucial for motility than adherence, but the dynamic polymerization and depolymerization of microtubules are required for both types of cellular activities.