From aviation to automotive - a study on material selection and its implication on cost and weight efficient structural composite and sandwich designs.

The design of a composite material structure is often challenging as it is driven by the trade-off between lightweight performance and production costs. In this paper, the boundaries of this design trade-off and its implications on material selection, geometrical design and manufacturability are analysed for a number of design strategies and composite material systems. The analysis is founded on a methodology that couples weight-optimization and technical cost modelling through an application-bound design cost. Each design strategy is evaluated for three levels of bending and torsional stiffness. The resulting stiffness-versus cost-range together constructs the design envelope and provides guidelines on the suitability and improvement potential of each case. Design strategies researched include monolithic, u-beam-, sandwich-insert- and sandwich-stiffened plates. Considered material systems include carbon-, glass, recycled carbon-, lignin- and hemp-fibre reinforced composites. Optimized sandwich designs are shown to have lowest design cost. Glass-, recycled carbon-, lignin- and hemp-fibre reinforced composite materials are all shown to reduce costs but at lower stiffness performance. Ultimately, the case study demonstrates the importance of early structural design trade-off studies and material selection and justifies introducing novel fibre systems in low-cost applications of moderate stiffness levels.

Primary squamous cell carcinoma of the submandibular salivary gland: a rare entity.

Salivary gland tumors make up about 3% of all neoplasms of the head and neck. Salivary gland tumors vary widely in histopathological appearance, thus it prompted the development of a revised histopathological classification of tumours. Malignant tumors can arise in the major salivary glands or numerous minor salivary glands lining the mucosa of the upper aerodigestive tract. This case highlights one of the rare variants of primary squamous carcinoma of the sub mandibular salivary gland and the management of submandibular salivary gland malignancies.

Percutaneous Radiofrequency Rhizotomy in Treatment of Trigeminal neuralgia: A Prospective Study.

INTRODUCTION: Trigeminal neuralgia (TN) often called as "Tic douloureux" is a syndrome characterized by paroxysmal facial pain, is one of the most painful and debilitating craniofacial pain disorders. The controversy regarding the etiology and treatment of TN still exists. OBJECTIVE: To evaluate the effectiveness of percutaneous radiofrequency rhizotomy (PRR) for TN, after failure of pharmacological management. METHOD: A nonrandomized, non comparative, descriptive, in vivo study of 15 patients with TN of maxillary and mandibular divisions of trigeminal nerve and patients with pain refractory to pharmacological management were done. It was performed as an O.P.D procedure. A routine follow up was done in all cases for 1 year. RESULTS: In a total of 15 patients, 8 female and 7 male patients were enrolled for the study. Early pain relief (immediately, postoperatively to 6 month) classified as excellent or good (successful), occurred in 12 of 15 patients (80 %). Fair or poor pain relief (unsuccessful) occurred in three patients (20 %).There was no mortalities and no major morbidity. SUMMARY: It was found that surgical treatment with PRR is a safe and effective way to manage patients with TN in whom pharmacologic therapy is either ineffective or not tolerated, with low side effects which are well tolerated.

"Transport distraction osteogenesis for reconstruction of mandibular defects": our experience.

INTRODUCTION: Mandibular defects usually involve a combination of osseous and soft tissue deficiency and are among the most challenging problems in maxillofacial surgery, many options are available for mandibular reconstruction. One of the options discussed in literature recently being distraction osteogenesis. AIM AND OBJECTIVE: The aims and objectives of the study were to evaluate clinically the technique of distraction osteogenesis to reconstruct mandibular defects, using indigenous transport distractors, and to evaluate the efficacy of Indigenous transport distraction osteogenesis device. MATERIALS AND METHODS: A prospective, experimental study was designed to examine the use of transport distraction osteogenesis in the treatment of defects of the mandible. Four patients with defects of the mandible were subjected to distraction osteogenesis with indigenously manufactured distraction device. The regenerate was assessed clinically and radiographically. RESULTS: The results showed that the regenerate was clinically as hard as the adjacent unaffected mandible and radiologic evidence of bone regeneration was observed. The major advantage being regeneration of hard tissue and soft tissue components without the morbidity of donor site, so that functional rehabilitation of the patient is possible. CONCLUSION: Thus from our study it is shown that transport distraction osteogenesis using indigenous distractors is a reliable yet affordable option for reconstruction of mandibular defects.

Bilateral pedicled nasolabial flaps for the anterior alveolus mandibular defect: a review.

With the increasingly wide spread application of microvascular free tissue transfer technique for oral cavity reconstruction, the routine need for variety of local and regional flap has decreased. However, a number of such flaps remains quite useful and should be included in modern armamentarium of reconstructive surgeon. Nasolabial flap is versatile, simple, easy to harvest local flap that can cover a variety of defect in face. We present the success and utility of bilateral pedicled flap for reconstruction of mandibular anterior alveolus after the wide excision of squamous cell carcinoma of mandibular anterior alveolus. And the restoration of esthetics and functional dental health with the artificial prosthesis. Patient had been followed for two years and six month with no signs of recurrence as yet.

Analysis of in vitro and in vivo sensitivity of oral cancer cells to methotrexate.

AIM: The present study was directed on the assessment of the response of treatment-naive oral cancer cells to methotrexate (MTX) in vitro: and clinical response to MTX therapy. METHODS: A pilot study of in vitro: evaluation of MTX response of oral cancer cells from 10 patients was conducted using a cell viability assay to determine the sensitivity/resistance to MTX. Quantitative in vitro: data were correlated to the clinical outcome to MTX therapy. RESULTS: A positive correlation was observed between the effect of MTX on tumor cells in vitro: and clinical response for 7 out of 10 patients. CONCLUSIONS: Observations from the proof-of-principle pilot study suggests that oral cancer cells have intrinsically variable response to MTX. Confirmation of these findings with a larger cohort of patients could aid in the development of individualized therapies for this class of malignancy.

Decompression and cystectomy of the odontogenic keratocysts of the mandible: a clinical study.

OBJECTIVES: Owing to the aggressive nature of OKC's if one could stop or even reverse the growth of the cyst with a simple procedure like decompression, regardless of the histologic type, it would be an alternative to radical and disfiguring surgery. METHODS: Eight patients who were diagnosed with Odontogenic keratocyst of the mandible were chosen and the first stage of treatment being, insertion of the decompression stent into the most prominent or dependent part of the cystic cavity. Then based on assessment of regular second monthly OPG radiograph the second stage ie. Enucleation of the cyst and treatment of the cystic cavity with Carnoy's solution was carried out, when the size of the cystic cavity had decreased. RESULTS: The radiographs of all the patients were analyzed at a two month interval and compared with the pre operative radiograph. The percentage of change in radiodensity of the lesion ranged from 35.15% to 66.16% with a mean decrease of 53.85%. This also indicated that the quantum of bone regeneration which occurred simultaneously and as observed during the cystectomy procedure was commendable. CONCLUSION: Reduction of surgical morbidity while preserving anatomy and function, is the greatest advantage of decompression, however one should not forget the emphasis on the value of long term studies needed to be carried out with regular follow-up, to keep a check on those patients treated with decompression.

Pediatric injuries in maxillofacial trauma: a 5 year study.

Fractures of the facial skeleton in children are less frequent. This clinical retrospective study of 5 year was conducted on 95 patients aged less than 16 years who sustained maxillofacial injuries during the period 2003 to 2008. Age, sex, etiology incidence and type of fracture were studied. The ratio of boys to girls was 1.9:1. The 7-12 year age group was commonly involved and the highest incidence was at age of ten years. Falls were the most common cause of injury accounting for 41%, followed by road traffic accidents (30%). Sports related injuries, assault and child abuse were also the causes of injury in children. Dentoalveolar injuries were found to be highest incidence with 42.1% followed by mandibular fractures. The soft tissue injuries were associated the pediatric maxillofacial trauma were found to be 34.7% of all cases.

Angioleiomyoma of cheek: report of two cases.

Leiomyomas are benign tumors derived from smooth muscle that most commonly arise in the uterus, followed by the gastrointestinal tract and subcutaneous tissues. Deep presentations are typically asymptomatic unless they achieve substantial size, whereas subcutaneous presentations may be associated with considerable local tenderness and pain, in addition to alteration of the overlying skin color. The highest incidence occurs between 40 and 49 years of age in the orofacial region, the angiomyoma is the predominant subtype, representing nearly 75% of all reported cases [1]. Oral leiomyomas are considered uncommon neoplasms, accounting for about 0.065% [2]. Despite the rather characteristic histopathologic features of the leiomyoma, a definitive diagnosis often depends on the confirmation of smooth muscle origin by immunohistochemical studies. We report two cases of angioleiomyoma of cheek with their clinical presentation histopathological features and surgical techniques employed. No recurrence has been seen as of yet in both of our cases.

Expression of oncofoetal marker carcinoembryonic antigen in oral cancers in South India--a pilot study.

Expression of the oncofoetal glycoprotein, carcinoembryonic antigen (CEA), has been observed in a number of malignancies and is also being pursued as a target for anti-cancer therapy. This study explored the status of this biochemical entity in the oral squamous cell carcinoma (SCC) in South India caused by extensive chewing habits. Squamous cell carcinoma in the study belonged to grade I and grade II. Tumour staging of the patients recruited in the study ranged from T2N1M0 to T4N3M0. Of the grade II cases studied, 88% (7 out of 8) showed expression of CEA. The 2 cases of grade I SCC of buccal mucosa also showed positive anti-CEA staining. If the results from this pilot study can be validated with a larger sample size, a role can be attributed to this tumour marker in oral neoplasia, thereby opening up avenues for using CEA as an additional diagnostic marker in oral SCC in this population and as a possible target for anti-cancer therapy.

Very strong C-H...O, N-H...O, and O-H...O hydrogen bonds involving a cyclic phosphate.

Very short C-H...O, N-H...O, and O-H...O hydrogen bonds have been generated utilizing the cyclic phosphate [CH2(6-t-Bu-4-Me-C6H2O)2]P(O)OH (1). X-ray structures of (i) 1 (unsolvated, two polymorphs), 1...EtOH, and 1...MeOH, (ii) [imidazolium](+)[CH2(6-t-Bu-4-Me-C6H2O)2PO2](-)...MeOH [2], (iii) [HNC5H4-N=N-C5H4NH](2+)[(CH2(6-t-Bu-4-Me-C6H2O)2PO2)2](2-)...4CH3CN...H2O [3], (v) [K, 18-crown-6](+)[(CH2(6-t-Bu-4-Me-C6H2O)2P(O)OH)(CH2(6-t-Bu-4-Me-C6H2O)2PO2)](-)...2THF [4], (vi) 1...cytosine...MeOH [5], (vii) 1...adenine...1/2MeOH [6], and (viii) 1...S-(-)-proline [7] have been determined. The phosphate 1 in both its forms is a hydrogen-bonded dimer with a short O-H...O distance of 2.481(2) [triclinic form] or 2.507(3) A [monoclinic form]. Compound 2 has a helical structure with a very short C-H...O hydrogen bond involving an imidazolyl C-H and methanol in addition to N-H...O hydrogen bonds. A helical motif is also seen in 5. In 3, an extremely short N-H...O hydrogen bond [N...O 2.558(4) A] is observed. Compounds 6 and 7 also exhibit short N-H...O hydrogen bonds. In 1...EtOH, a 12-membered hydrogen-bonded ring motif, with one of the shortest known O-H...O hydrogen bonds [O...O 2.368(4) A], is present. 1...MeOH is a similar dimer with a very short O(-H)...O bond [2.429(3) A]. In 4, the deprotonated phosphate (anion) and the parent acid are held together by a hydrogen bond on one side and a coordinate/covalent bond to potassium on the other; the O-H...O bond is symmetrical and very strong [O...O 2.397(3) A].

A potassium-18-crown-6 salt of a cyclic myo-inositol phosphate.

The six-membered phosphorinane ring in (1,4,7,10,13,16-hexaoxacyclooctadecane)potassium 2-O-benzoyl-1,3,5-O-methylidyne-myo-inositol 4,6-cyclophosphate trihydrate, [K(C(12)H(24)O(6))](C(14)H(12)O(9)P).3H(2)O, has a boat rather than a chair conformation. The K(+) ion is eight-coordinate and is connected to one of the phosphate O atoms, one of the O atoms of the myo-inositol residue and the six O atoms of the crown ether.

Methane production and oxidation in an anoxic rice soil as influenced by inorganic redox species.

The effects of addition of inorganic redox substances (species of NO3-, Mn4+, Fe3+, and SO4(2-)) on methane production and oxidation in anoxic rice (Oryza sativa L.) soil samples were examined. Sulfate was the most inhibitory for methane production followed by Fe3+, NO3-, and Mn4+, in that order. Addition of rice straw at a rate of 1% (w/w) as a carbon source to increase the electron donor to the electron acceptor ratio did not completely alleviate the inhibitory effects of redox species on methane production. Interestingly, laboratory incubation studies showed that addition of MnO2 and K2SO4 enhanced aerobic methane oxidation in soil samples held at 60% water holding capacity. The suspensions of pretreated soil samples with different redox species, when tested for their ability to oxidize methane in soil solution equivalent medium supplemented with respective redox species under aerobic and anaerobic conditions showed differential effects of redox species. Nitrate and Fe3+ stimulated methane oxidation under anaerobic conditions and retarded it under aerobic conditions. Manganese(IV) ion retarded methane oxidation under anaerobic conditions, but enhanced it under aerobic conditions. However, SO4(2-) stimulated methane oxidation in soil solution equivalent medium under both aerobic and anaerobic conditions.

Circulating levels in serum of total sialic acid, lipid-associated sialic acid, and fucose in precancerous lesion and cancer of the oral cavity.

Total sialic acid (TSA), lipid-associated sialic acid (LASA), and fucose were estimated in sera of 35 patients with precancerous lesion of the oral cavity, 68 patients with cancer of the oral cavity, and 25 age- and sex-matched non-chewers of both tobacco and betal nut and nonsmokers as controls. Significant elevation in the serum levels of TSA and LASA were observed in patients with the precancerous and cancer lesions when compared with the controls. Serum TSA levels were elevated significantly in patients with cancer when compared with those with precancerous lesions. Circulating TSA and LASA levels were found to reflect tumor burden and correlated well with stage of the disease. However, serum fucose levels did not show an increase corresponding to stage of the disease. The results suggests that combined evaluation of these markers may be useful in predicting early malignant change and also in assessing the spread and invasiveness of the disease in cancer of the oral cavity.

Efficacy and safety of granulocyte macrophage-colony stimulating factor (GM-CSF) on the frequency and severity of radiation mucositis in patients with head and neck carcinoma.

PURPOSE: Based on the clinical evidence of mucosal protection by GM-CSF during cytotoxic chemotherapy, a pilot study was undertaken to determine the safety and mucosal reaction of patients receiving GM-CSF while undergoing definitive conventional fractionated radiotherapy in head and neck carcinoma. METHODS AND MATERIALS: Patients were considered eligible if buccal mucosa and oropharynx were included in the teleradiation field. Ten adult patients with squamous cell carcinoma of head and neck (buccal mucosa--8 and posterior 1/3 tongue--2) were entered into the trial. Radiation therapy was delivered with telecobalt machine at conventional 2 Gy fraction and 5 fractions/week. The radiation portals consisted of two parallel opposing lateral fields. GM-CSF was given subcutaneously at a dose of 1 microg/kg body weight, daily, after 20 Gy until the completion of radiation therapy. Patients were evaluated daily for mucosal reaction, pain, and functional impairment. RESULTS: The median radiation dose was 66 Gy. Eight patients received > or = 60 Gy. The tolerance to GM-CSF was good. All 10 patients completed the planned daily dose of GM-CSF without interruption. Mucosal toxicity was Grade I in four patients till the completion of radiotherapy (dose range 50-66 Gy). Six patients developed Grade II reaction, fibrinous mucosal lesions of maximum size 1.0-1.5 cm, during radiotherapy. None developed Grade III mucositis. The maximum mucosal pain was Grade I during GM-CSF therapy. In two patients after starting GM-CSF the pain reduced in intensity. Functional impairment was mild to moderate. All patients were able to maintain adequate oral intake during the treatment period. Total regression of mucosal reaction occured within 8 days following completion of radiotherapy. CONCLUSIONS: GM-CSF administration concurrently with conventional fractionated radiotherapy was feasible without significant toxicity. The acute side effects of radiotherapy namely mucositis, pain, and functional impairment were nil to minimal. The results are suggestive of mucosal protection by GM-CSF during radiotherapy and warrants further study in randomized double blind trial.

Magliant melanoma of the oral cavity: report of 14 cases from a regional cancer centre.

Fourteen patients with oral mucosal malignant melanomas seen at a regional cancer centre over a 10-year period were analysed. All the patients presented with symptoms of short duration, with extensive local disease at initial evaluation in 11 patients. The palate was the commonest site involved. Ten patients had regional nodal disease and of these four also had distant metastases to the liver and/or the lung. Coincidental melanosis was identified clinically in three patients and histologically confirmed in two patients. Only four patients underwent radical surgery. Of the five patients who received DTIC-based chemotherapy, only one achieved a complete response. No significant correlation between stage of the disease at presentation, histological features or type of treatment and survival could be seen as the number of cases is small.

Serum vitamins' status in oral leucoplakias--a preliminary study.

Vitamins, such as A, beta carotene, C, E, B12 and folate, are the micronutrients with the strongest evidence of having a link to cancer prevention and control. Deficiency of these vitamins at the dietary, systemic or mucosal level will interact with tobacco use and increase the risk of oral precancerous lesions. The objective of this study was to (1) establish the baseline circulating levels of these vitamins in our normal population with and without tobacco use and (2) compare these levels with the values obtained in cases of oral leucoplakias. 50 normal controls with 25 each in chewers and non-chewers, matched for age and sex, were selected. 50 cases of oral leucoplakias (clinically detectable white patches) from the field constituted the study group. Simultaneous measurement of serum vitamin B12 and folate were carried out by radioassay. The other serum vitamins were estimated spectrophotometrically. Except for serum vitamin E, all the other serum vitamin levels were significantly decreased in oral leucoplakias compared to the controls. Cancer chemopreventive agents acting as inhibitors of both initiation and promotion, as analysed in our population, is promising for further intervention trials.