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Objective(s): During aging, cerebral structures undergo changes due to oxidative stress. The consumption of some plants seems to improve neurological health. For example, rosemary extract (RE) which is widely used as a flavoring food has anti-inflammatory and anti-oxidant activities. Therefore, we aimed to study the effect of RE on the changes related to the aging process in the prefrontal cortex (PFC).Materials and Methods: Twenty-four male Wistar rats including young and old were purchased. Each group was divided into two subgroups: vehicle and rosemary (old vehicle (OV), old rosemary (OR), young vehicle (YV), and young rosemary (YR) groups). Then, we examined the number of intact neurons, myelin base protein (MBP), white matter (WM), levels of malondialdehyde (MDA), and glutathione peroxidase (GPx) in the PFC. Results: The results showed that in the old vehicle rats compared to the young group without treatment, except for the MDA level (which increased), other variables significantly decreased (P≤0.05). Additionally, RE consumption demonstrated a significant elevation of WMA, MBP intensity, number of intact neurons, and GPx activity level, while MDA levels significantly reduced in the treated old rats compared to the old vehicle group (P≤0.05). However, there was no significant difference between the OR and YV groups (P≥0.05). Conclusion: Overall, it seems that RE can protect and improve aging damages in the PFC due to its anti-oxidant properties. So, the use of RE can be a suitable strategy to prevent aging complications in the brain.

Introduction:Dystonia is a disorder of movement caused by various etiologies. Laryngeal dystonia is caused by the spasm of laryngeal muscles. It is a disorder caused by vocal fold movement in which excessive adduction or abduction of the vocal folds occurs during speech. The pathophysiology of this type of dystonia is not fully known. Some researchers have suggested that basal ganglia structures and their connections with cortical areas have been involved in the pathogenesis of dystonia. Case Report:In this paper a 7.5-year-old boy suffering from laryngeal dystonia with bilateral lesions in Globus Pallidus is presented. The patient also suffered from swallowing problems, monotone voice, vocal tremor, hypersensitivity of gag reflex, and stuttering. Drug treatment failed to cure him; therefore, he was referred to rehabilitation therapy. Conclusion:In conclusion, special attention should be brought upon laryngeal dystonia, especially in patients showing Extra-pyramidal symptoms and/or abnormalities of the basal ganglia. In children, laryngeal dystonia may be potentially fatal. Lack of consideration for this condition during rehabilitation therapy can lead to serious consequences for a child.

Congenital fusion of cervical vertebrae is a rare anomaly. In this condition, two fused vertebrae appear structurally and functionally as one. This anomaly may be symptomatic or asymptomatic. Myelopathy, limitation in neck movement, muscular atrophy and regional sensory loss are examples of probable morbidity associated with this anomaly. Combination of genetic and environmental factors are involved in pathogenesis of this anomaly. Malformation of notochord, poor performance of retinoids, decreased local blood supply of spine and alteration in genes expression, especially members of Hox and Pax family genes are some of the proposed reasons of congenital fusion of cervical vertebrae. Diagnosis of this congenital anomaly in childhood seems to have an important role in prevention of probable secondary disorders in adulthood. We offer to clinicians that after performing careful physical tests and noticing the presence of signs and symptoms that mentioned in this paper, if a patient suspected to have congenital fusion of cervical vertebrae, genetic tests ought to be performed.

دیابت حاملگی، یکی از شایع‌ترین و مهم‌ترین اختلالات متابولیک است و می‌تواند باعث چندین ناهنجاری جنینی شود. افزایش قند خون در مادر، می‌تواند اثرات تراتوژنیک بر تکامل سیستم اعصاب مرکزی جنین داشته باشد. شواهد متعددی مشخص کرده است که بچه‌های متولد شده از مادران مبتلا به دیابت، اختلال در رفتار و عملکردهای هوشی را نشان می‌دهند. تشکیلات هیپوکامپ، یکی از نواحی حساس به گلوکز و ناحیه‌ی اصلی در تشکیل و تداوم حافظه‌ی درازمدت است. نوروژنز نیز در هیپوکامپ زمینه‌ی اصلی برای پلاستیسیتی نورونی بوده و با تشكیل حافظه و عملکردهای شناختی در ارتباط است. در این مقاله‌ی مروری، به بررسی اثرات دیابت بر سیستم عصبی در دوره‌ی بارداری پرداخته می‌شود.

Background: Nowadays, adipose-derived stem cells (ADSCs) are widely used for cartilage tissue engineering. However, most studies are in the field of scaffolds, growth factors and mechanical stimulation methods. But, few studies have been conducted regarding changes in surface markers during chondrogenesis. Accordingly, this study aimed to assess the changes in surface markers CD14 and CD44 during chondrogenesis. Methods: Human subcutaneous adipose tissue were isolated and cultured from 3 persons influenced by collagenase enzyme and stem cells. The cells of second passage were used for flow cytometry analysis of CD14 and CD44 surface markers. Second passage cells were cultured in alginate scaffolds under the influence of chondrogenic medium. Differentiated cells at the days 7 and 14 were used to evaluate CD14 and CD44 surface markers. Findings: The mean expression of CD44 in ADSCs was 96.8% but CD14 did not expressed in 98.6% of the cells. In stem cells, the mean expression of CD44 differentiated in alginate scaffolds on the day 7 was 96.3%; but on the day 14, it fell to 52.8%. The mean expression of CD14 at the days 7 and 14 was 99.7% and 99.9%, respectively. Conclusion: Our investigation revealed that the stem cells and differentiated cells at the day 7 express CD44 at high level, but at day 14, the expression of CD44 in differentiated cells is reduced. CD14 is not expressed on stem cells but in differentiated cells is expressed in high level. Due to these changes in surface markers during chondrogenesis, using them can be offered to determine chondrogenesis and to compare differentiated and normal chondrocytes.

Background: Osteoarthritis is one of the most common diseases in middle-aged populations in the World and could become the fourth principal cause of disability by the year 2020. One of the critical properties for cartilage tissue engineering (TE) is the ability of scaffolds to closely mimic the extracellular matrix and bond to the host tissue. Therefore, TE has been presented as a technique to introduce the best combination of cells and biomaterial scaffold and to stimulate growth factors to produce a cartilage tissue resembling natural articular cartilage. The aim of study is to improve differentiation of adipose derived stem cells (ADSCs) into chondrocytes in order to provide a safe and modern treatment for patients suffering from cartilage damages. Methods: After functionalization, dispersions and sterilizing carbon nano-tubes (CNTs), a new type of nanocomposite gel was prepared from water-soluble CNTs and alginate. ADSCs seeded in 1.5% alginate scaffold and cultured in chondrogenic media with and without transforming growth factor-β1 (TGF-β1 ) for 7 and 14 days. The genes expression of sex determining region Y-box 9 (SOX9), types II and X collagens was assessed by real-time polymerase chain reaction and the amount of aggrecan (AGC) and type I collagen was measured by ELISA. Results: Our findings showed that the expression of essential cartilage markers, SOX9, type II collagen and AGC, in differentiated ADSCs at the concentration of 1 μg/ml CNTs in the presence of TGF-β1 were significantly increased in comparison with the control group (P < 0.001). Meanwhile, type X collagen expression and also type I collagen production were significantly decreased (P < 0.001). Conclusions: The results showed that utilized three-dimensional scaffold had a brilliant effect in promoting gene expression of chondrogenesis.

Objective(s): Osteoarthritis is one of the most common diseases in middle-aged population in the world. Cartilage tissue engineering (TE) has been presented as an effort to introduce the best combination of cells, biomaterial scaffolds and stimulating growth factors to produce a cartilage tissue similar to the natural articular cartilage. In this study, the chondrogenic potential of adipose derived stem cells (ADSCs) was compared with natural articular chondrocytes cultured in alginate scaffold. Materials and Methods: Human ADSCs were obtained from subcutaneous adipose tissue and human articular chondrocytes from non-weight bearing areas of knee joints. Cells were seeded in 1.5% alginate and cultured in chondrogenic media for three weeks with and without TGFβ3. The genes expression of types II and X collagens was assessed by Real Time PCR and the amount of aggrecan (AGC) and type I collagen measured by ELISA and the content of glycosaminoglycan evaluated by GAG assay. Results: Our findings showed that type II collagen, GAG and AGC were expressed, in differentiated ADSCs. Meanwhile, they produced a lesser amount of types II and X collagens but more AGC, GAG and type I collagen in comparison with natural chondrocytes (NCs). Conclusion: Further attempt should be carried out to optimize achieving type II collagen in DCs, as much as, natural articular chondrocytes and decline of the production of type I collagen in order to provide efficient hyaline cartilage after chondrogenic induction, prior to the usage of harvested tissues in clinical trials.

Background: Bone diseases and injuries, including bone fractures during accidents and trauma, in all communities are prevalent and in most cases, crushed bone is not able to repair; various treatment ways including tissue graft from an allograft or autograft have risks and lead to problems. One method for treatment of bone fractures is using outologous osteoblasts with culturing on suitable scaffolds and then implant of cells to defect region. In this study, we cultured osteoblast cells on monolayer and calcium phosphate hydroxyapatite (HA-TC) scaffolds and the behavior of these two types of cells in different cultures were analyzed. Methods: During the craniotomy operation in Alzahra hospital in five individual, bone samples were obtained and in sterile condition were sent to the laboratory. Each sample after washing with PBS was cut into small pieces and plates containing the medium culture were transferred to the incubator. After 10-12 days, the cells have started to leave the bones covering the floor plate and after using the enzyme Trypsin_EDTA isolated from plate divided into two groups. One group was cultured in HA-TC scaffold and other as monolayer culture. Van kossa staining, flow cytometry, alkaline phosphatase assay and MTT method were used to investigate the characteristics of osteoblasts. Finding: Osteoblasts in monolayer culture were observed as fibroblast- like cells. Van kossa staining determined the mineral deposits in the two groups. The cell proliferation increased in cellular scaffolding HA-TC more than monolayer (P < 0.001). Results of MTT showed more activity items on living cells in scaffold HA-TC than monolayer (P < 0.001). In alkaline phosphatase staining, blue granules were observed; in the flow cytometry, 57 percent of primary cultured cells and 5 percent in the third passage cells showed alkaline phosphatase marker. Conclusion: According to the results of this study, the hydroxyapatite scaffold is better than monolayer culture for osteoblast cells. This could be because of having more calcium and similar elements to bone matrix that facilitate feeding cultured cells.

Constipation is one of the most common complains in each society, especially, in children and old populations. In this study, we hypothesized that the stimulation of gum epithelium by traditional wooden toothbrush would have a trigger effect on gastro-colic reflex, and thus, the aim of this study was to investigate the effect of traditional wooden toothbrush usage on improvement of constipation symptoms in patients with spinal cord injury (SCI). Traditional wooden toothbrush is a special toothbrush taken from a plant called Salvadora Persica with antimicrobial and anti-germ effects. It is commonly known as “the brush of Mecca”. In a clinical trial work, 61 patients with spinal cord injury were selected who had injuries in different spinal levels (cervical, thoracic and lumbar). They were recommended to use traditional wooden toothbrush for 5 minutes twice a day, after breakfast and dinner, over a 6-week period. Regarding to changes in their gastrointestinal habits during the period of using the wooden toothbrush, they were advised to complete a questionnaire. All symptoms of bowel problems improved significantly after the 6-weeks intervention. For example, after this intervention, a patient who had one defection every 3 weeks, obtained 3 defecations every week. Keywords: Traditional wooden toothbrush, Constipation, Spinal cord injury

Background: Dementia as a major cognitive neurological disorder is defined as impairment in one or more cognitive territories compared with the former level of performance. This disorder disrupts patient's independence, and the patient would need others aid in order of doing daily and complex activities. The aim of this study was to evaluate the efficacy of Rosa damascena extract in the improvement of cognitive function in patients with dementia. Methods: This study is a randomized double-blind, placebo-controlled clinical trial on 40 patients older than 55 years with dementia referred to Specialized Elderly Patients Clinic in 2015–2016. Patients were divided randomly into two groups (control and intervention). The intervention group used donepezil and R. damascena capsules, and in control group, placebo capsule instead of R. damascena added on donepezil. Four test was filled three times at the study initiation, after month one and also after month three: Mini–Mental State Examination (MMSE) and Addenbrooke's Cognitive Examination Revised (ACE-R) were used for cognition evaluation, for depression assessment, Geriatric Depression Scale was administered, and checklist of memory and behavioral disorders were filled. Results: The results showed add-on donepezil and R. damascena versus placebo improved cognitive impairment based on MMSE with P = 0.002, ACE-R with total P = 0.001, depression (P = 0.012), behavioral disorders (P < 0.001), and daily activity (P < 0.001). Conclusions: The R. damascena extract affected cognitive impairment of dementia patients significantly and also have significant effects on improving depression and behavioral problems.

Background:Cartilage damaged by trauma or degenerative arthritis has a limited capacity for regeneration most likely because of its avascularity and low cellularity. In this study, adipose–derived stem cells were cultured in chondrogenic medium supplemented isolated from adipose tissue then were induced for chondrogenesis with BMP-6 in pellet culture system. Methods: Human adipose tissues obtained from cesarean section and ADSCs were isolated and characterized by flowcytometry techniques for CD14, CD44, CD45, and CD90 markers. To induct of chondrogenesis ADSCs were cultured in pellet culture for 21 days in chondrogenic medium supplemented with BMP-6. Resulted constructs were investigated by histological, immunohistochemical and RT-PCR methods. Findingss: ADSCs were expressed CD44, CD90 and not CD14 or CD45. ADSCs chondrogenesis was occurred successfully. Stained-sections in H-E and alcian blue were showed chondrocytes in lacuna with sulfated proteoglycans extracellular matrix. Existence of collagen type-II and aggrecan was proved in constructs by immunohistochemical study. RT-PCR method was exhibited collagen type-II and aggrecan genes expression in differentiated cells. Conclusion: Human adipose-derived stem cells are excellent candidate for cartilage tissue engineering. In pellet culture ADSCs in presence of BMP-6 were induced for chondrogenesis. Key word: Chondrogenesis, Adipose-derived stem cells, Tissue engineering, Collagen type II, BMP-6, Pellet culture system.

BACKGROUND: A common polymorphism at codon 72 of TP53 gene has been associated with increased risk for many human cancers. We studied this TP53 polymorphism in colorectal adenocarcinomas in small population selected from Isfahan city. METHODS: Samples: We undertook a case-control study on 180 controls and 180 paraffin block specimens of sporadic colorectal adenocarcinomas. PCR amplification of TP53 codon 72 polymorphism: TP53 codon 72 genotypes were detected by PCR using specific primer pairs for amplifying the Proline or the Arginine alleles. STATISTICAL ANALYSES: The 42-test was used to assess the significance of any difference in the prevalence of TP53 codon 72 polymorphism between colorectal cancer patients and controls. RESULTS: In control samples, the genotype distribution for TP53 polymorphism showed 28.3%, 48.9% and 22.8% for the Arginine/Arginine, Arginine/Proline and Proline/Proline genotypes, respectively. In the cancer group 40% of the cases were Arginine/Arginine, 42.2% were Arginine/Proline and 17.8% were Proline/Proline. A significant difference between cases and controls was found for the Arginine/Arginine genotype compared with (grouped) Arginine/Proline and Proline/Proline genotypes (Odds Ratio = 1.686 (1.085-2.620), P = 0.02). CONCLUSIONS: TP53 codon 72 polymorphism may be a genetic predisposing factor for colorectal adenocarcinomas in Isfahan city. KEYWORDS: Colorectal adenocarcinoma, TP53, Arginine, Proline, Polymorphism.

In this study, chondrocyte culture was established for the first time in Iran,and calcium alginate was used for longer culture of chondrocyte in vitro. Thestudy was programmed in order to be used for future human chondrocytetransplantation. The cartilage specimen obtained from 50 patients whounderwent total knee and hip operations in Isfahan University of MedicalSciences. Cartilage specimens were used for monolayer as well as suspensionculture in alginate beads. Approximately 12±1 millions cells were harvestedfrom the 3rd passage. The cells were round with large euchromatic nucleusand several nucleoli and small vacuoles. The cells derived from passages 1to 4, which were grown up then, in alginate beads, showed higher stainingwith alcian blue. The harvested cells in some patients were immediately andsuccessfully used for autologus transplantation. This later work will be reportedseparately.

Background: Diabetes in pregnancy is a common metabolic disorder associated with various adverse outcomes in the offspring including impairments in attention and memory and alterations in social behavior. Glial cells are proven to have a critical role in normal function of neurons, and alteration in their activity could contribute to disturbance in the brain function. The aim of this study was to investigate the effect of maternal diabetes on hippocampal mRNA expression and distribution pattern of glial fibrillary acidic protein (GFAP) immunoreactive glial cells in the dentate gyrus (DG) of rat neonate at postnatal day 14 (P14). Materials and Methods: Wistar female rats were randomly allocated in control, diabetic, and insulin-treated diabetic groups. Diabetes was induced by injection of streptozotocin from 4 weeks before gestation until parturition. After delivery, the male offspring was euthanized at P14. Results: Our results showed a significant higher level of hippocampal GFAP expression and an increase in the mean number of GFAP positive cells in the DG of diabetic group offspring (P < 0.05). We also found an insignificant up-regulation in the expression of GFAP and the mean number of positive cells in the insulin-treated diabetic group neonates as compared to control group (P > 0.05). Conclusion: The present study revealed that diabetes during pregnancy strongly increased the glial cells production in the developing rat hippocampus.

Background: Diabetes mellitus is associated with cognitive deficits in humans and animals. These deficits are paralleled by neurophysiological and structural changes in brain. In diabetic animals, impairments of spatial learning, memory, and cognition occur in association with distinct changes in hippocampus, a key brain area for many forms of learning and memory and are particularly sensitive to changes in glucose homeostasis. However, the multifactorial pathogenesis of diabetic encephalopathy is not yet completely understood. Apoptosis plays a crucial role in diabetes-induce neuronal loss in hippocampus. Methods: The effects of diabetes on hippocampus and cognitive/behavioral dysfunctions in experimental models of diabetes are reviewed, with a focus on the negative impact on increased neuronal apoptosis and related cellular and molecular mechanisms. Results: Of all articles that were assessed, most of the experimental studies clearly showed that diabetes causes neuronal apoptosis in hippocampus through multiple mechanisms, including oxidative stress, inhibition of caspases, disturbance in expression of apoptosis regulator genes, as well as deficits in mitochondrial function. The balance between pro-apoptotic and anti-apoptotic signaling may determine the neuronal apoptotic outcome in vitro and in vivo models of experimental diabetes. Conclusions: Dissecting out the mechanisms responsible for diabetes-related changes in the hippocampal cell apoptosis helps improve treatment of impaired cognitive and memory functions in diabetic individuals.

Background: Cartilage damages and diseases such as osteoarthritis are rather worldwide problems of many people. In addition, articular cartilage has a limited ability to repair. Current treatment methods for cartilage tissue injuries lead to formation of fibrous tissue, apoptosis, and further cartilage degeneration. Therefore, engineering of cartilage tissue with adult stem cells is considered necessary. This study aimed to investigate the effect of TGF-β3 and BMP-6 growth factors on chondrogenic differentiation of adipose-derived stem cells in alginate scaffold. Methods: Stem cells were isolated from human subcutaneous adipose tissue with collagenase enzyme digestion. The isolated cells were treated with chondrogenic medium supplemented with TGF-β3 and BMP-6 on alginate scaffold then harvested after 3 weeks. Histological, immunohistochemical and RT-PCR methods were performed for assessment of cartilage–specific markers. Findings: Our results revealed that chondrogenesis of ADSCs on alginate scaffold induced by TGF-β3 and BMP-6 growth factors. Immunohistochemical method was shown deposition of typical cartilage extracellular matrix components such as type II collagen and aggrecan in constructs. RT-PCR analysis of cartilage-specific genes, also confirmed the induction of the chondrocytic phenotype upon stimulation with TGF-β3 and BMP-6. Also, TGF-β3 and BMP-6 together increased the expression of aggrecan gene in compare with one growth factor alone. Conclusion: It can be concluded that TGF-β3 and BMP-6 promote chondrogenesis of ADSCs in 3-D culture and the use of both growth factors together increase the expression of aggrecan gene in compare with one growth factor alone. Key words: Adipose-derived stem cells, Alginate, Tissue engineering of cartilage, BMP-6, TGF-β3.

Background: Anatomists had been searching to find methods for preserving soft human tissues and produce natural samples with durable, dry, odorless, and portable in briefcase properties. Plastination is a modern method for preparing such tissue samples. In plastination, water and fat are extracted from tissues and replaced with a dissolver fluid, which in its turn is replaced with a special kind of polyester. Usually, the organs like hearts, lungs, kidneys, striated muscles, vessels, nerves, connective tissue, etc, which are treated with formalin, loss their beautiful color and take a dull appearance after fixation. Tissue staining with natural dyes is one method for somehow preserving tissue natural color and increasing its appearance activity to prepare better samples in terms of appearance and suitable clearance of different parts (valves, muscles, trabeculae…). Also, we have to prepare non fragile samples. Methods: At first, some visceral organs (sheep hearts) were prepared and fixed by formalin 5% for 4 to 10 days. Then they were dissected for anatomic details and were put in a chemical dye called eosin and natural dye called ronnas. After dehydration by acetone in -25 °C and defeating with acetone in +30 °C, samples were put in the vacuum chamber to replace acetone instead of polymer under the vacuum pressure; finally the samples were cured with the ultra violate wave. Findings: We found that after fixation and before plastination staining of organs with eosin and ronnas resulted in beautiful appearance of tissues. Conclusion: Staining of organs resulted in beautiful appearance of tissues which are effective in increasing the attractively of teaching and learning anatomy. Also, it has affection in the raising appearance quality and has positive impression in the quality of education. Keywords: Plastination, Natural dye, Industrial dye, Polyester.

Introduction: After bone fractures from traffic trauma, many patients suffer from non-healing bone defects and its cosmetic and psychological complications. So, it is important to identify modern and effective methods to improve healing of bone defects. One of these, is using bone cells from the patient, culturing these cells on appropriate scaffold, and finally transferring them to injured area. The main objective of this study was to compare the rate of osteoblast proliferation in alginate beads, and hydroxyapatite-tricalcium phosphate (HA-TC) scaffold. Methods: Bone tissue specimens were obtained from 4 patients undergoing craniotomy surgery operations in Alzahra teaching hospital, Isfahan. Bone specimens were cut in to small pieces and put in Petri dishes having culture medium and transferred to the incubator. The mean interval of osteoblast outgrowth from bone pieces was observed to be 10-12 days, later on. The cell cultures reached confluence, averagely after 2 weeks time. First passage cells were detached from Petri dishes using Trypsin_EDTA and were divided in two portions. One portion was used for hydroxyapatite-tricalcium pohosphate scaffold, and the other was added to alginate gel. After a 2-weeks period, the data were collected and analyzed. Results: The osteoblasts in hydroxyapatite-tricalcium phosphate scaffold and alginate gel had round morphology. Van kossa staining demonstrated mineralized matrix in both groups. The number of harvested cells in 2 weeks after culture was significantly higher in Alginate group (P < 0.001). In addition, MTT assay showed significant difference in the mean of viability rates between both groups in day 14 (P < 0.001). Conclusion: This study showed that Alginate gel support better proliferation and viability of osteoblasts in comparison with the hydroxyapatite-tricalcium pohosphate scaffold. The probable cause of these differences can be searched in Alginate bioproperties. Porosity of Alginate gel provides conditions in which cellular and methabolic activities could be accelerated. Key word: Alginate, Bone healing, Hydroxyapatite-Calcium phosphate, Osteoblst.

Background: The scope of this study was to preserve whole detailed structure of dissected and decalcified bones, taken from used cadavers, by a new plastination technique. Materials and Methods: Specimens we used in this study were sheep femurs and human bones including pelvis, femur, tibia, and fibula. Bones, at first, fixed with 5% formalin and were decalcified with 5% nitric acid, and then were fixed again and washed under the tap water. The resulted flexible bones were dehydrated in -25΀C acetone and degreased them in +25΀C acetone. Then, the experimental and control specimen were placed in the vacuum chamber for forced impregnation with our new flexible unsaturated polyester resin (UP 89 method) and silicon resin (S 10 method), respectively. Finally, the strength and flexibility of plastinated decalcified specimens were investigated by tensometer, and the weight diversity was measured by digital balance. Results: Plastinated bones prepared by this technique were found to be dried, non-fragile, durable, odorless, non-greasy, and demonstrating all detailed structures of the bones. Tensile and weight tests results indicated that plastinated decalcified femurs have owned higher flexibility and strength but lesser weight than plastinated undecalcified femurs. The characteristics of both experimental and control groups of plastinated decalcified specimens were found to have no significant difference. Conclusions: Our synthesized resin found to be much more economical than conventional plastination method. In more details, properties of these new products were the same as, S 10 method, from points of strength, flexibility and weight, but, since the money cost for producing them was about one fifth that of S 10 method.