Probing the Interaction of NO with C60: Comparison between Endohedral and Exohedral Complexes.

Recent advances in synthetic methodologies have opened new strategies for synthesizing stable metal-free electron spin systems based on fullerenes. Introducing nitric oxide (NO) inside a fullerene cage is one of the methods to attain this goal. In the present study, dispersion corrected density functional theory (B3LYP-D3) has been used to evaluate the structure, stability, and electronic properties of NO encapsulated fullerene NO@C60 and compared those with its exohedral fullerene NO.C60 analog. The calculated stabilization energy for NO@C60 is appreciably higher than NO.C60, and this difference is comprehended via the Quantum theory of atoms in molecules (QTAIM) and noncovalent interaction (NCI) topological analyses. The delocalization of electron density of NO and the C60 cage in NO@C60 is discussed using electrostatic potential analysis. In addition, an attempt has been made to understand the different locations and orientations involving the interaction of two NO radicals and the fullerene C60. It is shown that the encapsulation of the NO dimer inside the C60 cage is an energetically unfavorable process. On the other hand, stable structures are obtained upon the physisorption of other NO on the surface of NO@C60 and NO.C60. The present work provides an in-depth understanding of the interaction of NO and C60 fullerene, its preferable position, and its orientation in both endohedral and exohedral complexes.

Practical consensus recommendations for gestational breast cancer.

This manuscript provides a practical and easy to use consensus recommendation to community oncologists on how to manage gestational breast cancer.

Needs of exploring the burden of recent onset seizures due to neurocysticercosis and challenges in southeast Asia focusing on scenario in Malaysia.

Seizures due to neurocysticercosis (NCC) is a neglected human-to-human transmitted disorder and an emerging problem worldwide. A substantial portion of recent onset seizures is known to be attributed to NCC in Taenia solium (T. solium) endemic areas where populations which neither raise pigs nor eat pig meat are also at risk. High prevalence of NCC causing epilepsy has been reported in the underdeveloped areas of Southeast Asia (SEA) however, only fragmentary information on its incidence is available in countries like Malaysia. In Malaysia T. solium infection was previously thought to be infrequent due to Muslim population majority and the religious prohibition of consuming pork, but it is not totally absent. There is an evident lack of knowledge and awareness of the actual burden, routes of transmission, and the impact of NCC in this region. The problem is assumed to be more prevalent particularly in cities because of the frequent inflow of possibly T. solium infected individuals or carriers among those who migrate from neighboring endemic countries to Malaysia. The issue of imported cases that are likely to be emerging in Malaysia is highlighted here. An accurate quantification of regional burdens of epilepsy due to NCC in Malaysia is warranted considering the disease emergence in its neighboring countries. It is suggested that the importance of NCC be recognized through quantification of its burden, and also to collect epidemiological data for its subsequent elimination in line of World Health Organization's mission for control of cysticercosis as a neglected tropical disease. In this review the need as well as a strategy for neuro-care center screening of epilepsy cases, and various issues with possible explanations are discussed. It is also proposed that NCC be declared as a reportable disease which is one of the eradicable public health problems in SEA.

Natural Gas Evolution in a Gas Hydrate Melt: Effect of Thermodynamic Hydrate Inhibitors.

Natural gas extraction from gas hydrate sediments by injection of hydrate inhibitors involves the decomposition of hydrates. The evolution of dissolved gas from the hydrate melt is an important step in the extraction process. Using classical molecular dynamics simulations, we study the evolution of dissolved methane from its hydrate melt in the presence of two thermodynamic hydrate inhibitors, NaCl and CH3OH. An increase in the concentration of hydrate inhibitors is found to promote the nucleation of methane nanobubbles in the hydrate melt. Whereas NaCl promotes bubble formation by enhancing the hydrophobic interaction between aqueous CH4 molecules, CH3OH molecules assist bubble formation by stabilizing CH4 bubble nuclei formed in the solution. The CH3OH molecules accumulate around the nuclei leading to a decrease in the surface tension at their interface with water. The nanobubbles formed are found to be highly dynamic with frequent exchange of CH4 molecules between the bubble and the surrounding liquid. A quantitative analysis of the dynamic behavior of the bubble is performed by introducing a unit step function whose value depends on the location of CH4 molecules with respect to the bubble. It is observed that an increase in the concentration of thermodynamic hydrate inhibitors reduces the exchange process, making the bubble less dynamic. It is also found that for a given concentration of the inhibitor, larger bubbles are less dynamic compared to smaller ones. The dependence of the dynamic nature of nanobubbles on bubble size and inhibitor concentration is correlated with the solubility of CH4 and the Laplace pressure within the bubble. The effect of CO2 on the formation of nanobubble in the CH4-CO2 mixed gas hydrate melt in the presence of inhibitors is also examined. The simulations show that the presence of CO2 molecules significantly reduces the induction time for methane nanobubble nucleation. The role of CO2 in the early nucleation of bubble is explained based on the interaction between the bubble and the dissolved CO2 molecules.

Two port laparoscopic ventral hernia mesh repair: an innovative technical advancement.

Ventral hernia is a common surgical problem. The traditional open surgical repair has the disadvantage of excessive morbidity, long hospital stay and high recurrence rates. Laparoscopic ventral hernia repair (LVHR) is gaining acceptance but there is no standardized technique for the repair of these hernias. We have introduced an innovative technique of 2-port laparoscopic mesh repair for ventral and incisional hernias. Between January 2002 and September 2008, 168 patients underwent the 2-port repair of ventral hernias at our institution, with Bard polypropylene mesh in 162 cases and Gore-tex expanded polytetrafloroethylene mesh in 6 patients. The average size of the defects was 10.2 cm (6.6-24.8 cm). Mean operating time was 61.4 min (48-102 min). The mean post-operative hospital stay was 1.2 days. Prolonged ileus over one day occurred in 22 patients while 6 patients had urinary retention in the post-operative period. There were 6 recurrences (3.94%) in the mean follow up period of 42 months (6-62 months). Seroma formation occurred in 5.3% cases but all of them subsided within 6 weeks without any active intervention. In conclusion we recommend that the 2-port LVHR is a technically sound procedure which is less invasive and with comparable complication rates to the 3 or 4 port hernia repair.

Inflammatory variant of a well-differentiated retroperitoneal liposarcoma: case report of a rare giant variety.

Inflammatory liposarcoma is a rare variant of a well-differentiated liposarcoma (WDLPS). We present a case of a 37 years old male who had a giant variety of this inflammatory WDLPS. CT scan revealed a large abdomino-pelvic mass abutting the left kidney and pushing the IVC, Aorta and the left ureter across the midline. CT guided FNAC did not reveal any malignant cells. A large 9-kg fibro-fatty mass, which appeared irregular, congested and bosillated was excised. Microscopic picture revealed foci of fibrosis with mature adipose tissue. Lymphocyte and plasma cell infiltrate was abundant along with multi-nucleate giant cells and few lipoblasts. There are no case reports of a giant inflammatory variant of WD-LPS in world literature and this is the first of its kind from the Indian sub-continent. We present a case report of this rare giant variant of inflammatory WDLPS and discuss the review of literature.

Giant pseudocyst of the anterior abdominal wall following mesh repair of incisional hernia: a rare complication managed laparoscopically.

UNLABELLED: Giant pseudocyst formation of the anterior abdominal wall, following on-lay polypropylene mesh repair for incisional hernia is an under reported complication. We report an unusual case of a 56-year-old female who underwent a polypropylene mesh repair of incisional hernia 2 years back. Subsequently she developed a giant pseudocyst of the anterior abdominal wall, which was occupying the whole of the abdomen from the xiphisternum to the pubic bone, and over both the flanks. Over a period of one year, the cyst had defied multiple attempts at aspiration. The patient underwent a laparoscopic drainage of the collection with piecemeal excision of the entire cyst wall. Histopathology of the cyst wall revealed necrotic material with intervening areas of hemorrhage. No epithelial lining was seen. There has been no recurrence in the two years of follow-up. CONCLUSION: giant pseudocyst of the anterior abdominal wall is a rare complication following mesh repair of an incisional hernia. Such pseudocysts can be managed successfully by laparoscopic procedures.

Laparoscopic management of gallstone presenting as obstructive gangrenous appendicitis.

We present an unusual case of a 55-year-old man with symptoms of recurrent appendicitis. Laparoscopy revealed a 1.5 cm gallstone impacted at the base of the appendix, leading to gangrenous appendicitis. This patient did not have any features of gallstone ileus. On imaging he had an inflammatory mass in the region of the right iliac fossa with a hyperintense shadow in the cecal area which was reported as an appendicolith. There was no demonstrable cholelithiasis or biliary-enteric fistula. There were dense omental adhesions in the pericholecystic area on laparoscopy. The case was successfully managed by laparoscopic appendectomy with retrieval of the gallstone. No surgery was undertaken for the gallbladder. Diagnosis was confirmed by biochemical analysis of the stone, which contained calcium bilirubinate and cholesterol. A gallstone obstructing the appendicular lumen is a very rare etiology of gangrenous perforation of the appendix peritonitis. This case was successfully managed laparoscopically.

Laparoscopic surgical management of perforative peritonitis in enteric fever: a preliminary study.

Early surgery in enteric perforation is the only accepted form of treatment in modem day medicine and gives excellent results. Exploratory laparotomy continues to be the mainstay of surgical treatment and several different procedures are recommended in literature. Between January 1998 and November 2001, we have successfully managed 6 consecutive cases of enteric perforation laparoscopically with complete resolution of the disease. There were 4 males and 2 females in our study. The mean time of presentation to us was 38 hours after the perforation (range 22 hours to 63 hours). The mean age was 32 years (range 28 years to 43 years). All patients presented with free air under the diaphragm. A laparoscopic approach was carried out through a 10 mm supraumbilical port and two 5 mm additional ports in the midline infraumbilical area and the left iliac fossa area. Simple one layer closure of the perforation was carried out with 2-0 silk intracorporeally and the peritoneal cavity was washed out and adequately drained. All perforations were localised to the terminal ileum and were single in number. The mean operating time was 54 minutes-(range 42 to 75 minutes). All patients received parenteral ofloxacin and metrogyl. Postoperative recovery was uneventful in all patients and there were no major complications. All patients were discharged from hospital by the 4th postoperative day. Follow up over a period of 12 to 16 months revealed all patients to be in normal health. We strongly recommend a first line laparoscopic approach in all patients with typhoid perforation; as it is a safe and effective method of managing such cases.

Analysis of glycoconjugates in patients with oral squamous cell carcinoma.

BACKGROUND: Our aim was to examine the levels of glycoconjugates in plasma, erythrocyte membranes and buccal mucosa of healthy subjects and oral cancer patients. SUBJECTS AND METHODS: This study was conducted on 48 adult male oral cancer patients with various clinical stages (stage II to stage IV; 16 of each) and 16 disease-free healthy subjects who underwent surgical removal of impacted teeth or vestibuloplasty without inflammation. RESULTS: The plasma and tumor tissues glycoconjugates levels were significantly increased, whereas the erythrocyte membranes glycoconjugates were significantly decreased in oral cancer patients as compared to healthy subjects. The levels of glycoconjugates were gradually increased from stage II to stage IV in plasma and tumor tissues and decreased in erythrocyte membranes from stage II to stage IV of oral cancer patients. CONCLUSION: The increased plasma glycoconjugates can be due to the expense of erythrocyte membrane glycoconjugates or tumor tissue itself.

Canalicular adenoma of the upper lip mimicking mucocele.

Salivary gland neoplasms are relatively rare. Among the salivary gland neoplasms minor salivary gland neoplasms are often deceptive to the clinician and challenging to the pathologist because of their varied morphology and diverse histopathological pattern. This article documents a case of canalicular adenoma of the upper lip mimicking mucocele and discusses the differential diagnosis of minor salivary gland neoplasms.

Unusual presentation of nasopharyngeal (juvenile) angiofibroma in a 45 year old female.

Juvenile nasopharyngeal angiofibroma is a rare tumour, comprising 0.05% of the head and neck tumours, histologically benign, locally invasive, and has a specific predilection for nasopharynx and adolescent males. This article presents an unusual case of nasopharyngeal angiofibroma in a 45-year-old female patient, manifesting as a destructive maxillary lesion and discusses the two most important factors regarding this tumour, the etio-pathogenesis and spread.

Biochemical changes in tumor tissues of oral cancer patients.

OBJECTIVES: Our aim was to assess the oxidative stress in tumor tissues of oral cancer patients by measuring the levels of lipids, thiobarbituric acid reactive substances (TBARS) and antioxidants. DESIGN AND METHODS: This study has been conducted on oral tumor tissues of 48 adult male oral cancer patients with various clinical stages (stage II to stage IV; 16 of each) and normal tissues of an equal number of age and sex matched disease free healthy subjects. The levels of lipids, lipid peroxidation and antioxidants in buccal mucosa of healthy subjects and oral cancer patients were assayed using colorimetric methods, except for vitamin E (fluorometriy). RESULTS: Total cholesterol and esterified cholesterol were markedly increased whereas phospholipids and free fatty acids were significantly decreased in tumor tissues as compared to normal tissues. The decrease in TBARS levels and functional compromise of antioxidant defense mechanisms were observed in the tumor tissues as compared to normal subjects. CONCLUSIONS: The low availability of peroxidizable substrates and the enhanced antioxidant capacity in tumor tissues make them less susceptible to oxidative stress, conferring a selective growth advantage on tumor cells.

Sequential Changes in the Cellular Redox State During 7,12-Dimethylbenz[a]anthracene-Induced Carcinogenesis in the Hamster Buccal Pouch.

Our objective was to elucidate sequential changes in the oxidant-antioxidant status during 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. In designing the study, we divided hamsters into experimental and control groups. The right buccal pouches of the experimental animals were painted three times a week with a 0.5% solution of DMBA in liquid paraffin. The control animals received paraffin alone. The hamsters were killed after 1, 4, 8, 12, and 16 weeks of DMBA treatment, and the buccal pouches were examined for histopathological changes. The extent of lipid peroxidation and the status of glutathione-dependent antioxidants were evaluated in the buccal pouch, liver, and erythrocytes. Our results showed that the experimental animals developed severe hyperplasia and hyperkeratosis after 4 weeks, dysplasia after 8 weeks, and well-developed squamous cell carcinomas after 16 weeks of DMBA application. Topical application of DMBA increased lipid peroxidation in the buccal pouch up to the 8th week; there was a substantial fall after 12 weeks and significantly low levels after 16 weeks. This was accompanied by a sustained increase in reduced glutathione (GSH) and the activities of glutathione peroxidase (GPx), glutathione-S-transferase (GST), and gamma-glutamyltranspeptidase (GGT) throughout the carcinogenic progression. However, in the liver and erythrocytes, the concentrations of lipid peroxides were higher, and GSH- and GSH-dependent enzyme activities were lower than in the controls throughout the experiment. This study has revealed intrinsic differences in the cellular redox state in the target organ and host tissues of tumor-bearing animals. We suggest that measurement of lipid peroxidation and GSH-dependent antioxidants could be valuable in evaluating carcinogenic progression and the effects of putative chemopreventive agents in the hamster buccal pouch model.

Gastroscopic-assisted laparoscopic cystogastrostomy in the management of pseudocysts of the pancreas.

Once pancreatic pseudocysts become persistent, unresolving, and symptomatic, surgical drainage is mandatory. Between January 1998 and December 2001, we performed five laparoscopic cystogastrostomies for such pseudocysts with the simultaneous use of the gastroendoscope. The mean cyst diameter was 20 cm (range, 18.5-24). In the first four cases, the anterior wall of the stomach was entered through two 10-mm balloon cannulae under gastroscopic guidance. By introducing the laparoscope through one port and a harmonic scalpel through the other, a wide cystogastrostomy was performed. In the fifth case, a modification of the above technique was carried out. A single 10-mm cannula was used to enter the stomach and, with the use of a side-viewing gastroduodenoscope as the camera source, the harmonic scalpel was used to create the cystogastrostomy. The punctures in the wall of the stomach were repaired with endosutures. The gallbladder was removed in all cases. The mean operating time was 110 minutes (range, 92-128) for the combined procedure. There were no postoperative complications, and the mean hospital stay was 4 days. Postoperative follow-up with ultrasonography over a period of 1 year in each case revealed complete resolution of the cyst. Laparoscopic cystogastrostomy using harmonic scalpel under gastroscopic control is an effective and rapid method of surgically managing such lesions.

Oxidant-antioxidant status in patients with oral squamous cell carcinomas at different intraoral sites.

OBJECTIVES: To compare the extent of lipid peroxidation and the status of antioxidants in tumor and venous blood of patients with oral squamous cell carcinoma (OSCC) at different intraoral sites. DESIGN AND METHODS: Twenty four patients with OSCC at different intraoral sites and an equal number of age- and sex-matched reference subjects were chosen for the study. The concentrations of lipid peroxides and reduced glutathione (GSH) and the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) were estimated in tissues and blood. RESULTS: Diminished lipid peroxidation in tumor tissue was accompanied by decreased activities of SOD and CAT with increase in GSH and GSH-dependent enzymes. In contrast, enhanced lipid peroxidation with decrease in antioxidants was observed in the venous blood of OSCC patients. CONCLUSION: No significant differences in lipid peroxidation and antioxidant levels were observed between patients with OSCC at different intraoral sites. However, our results revealed differences between the tumor and blood with respect to their susceptibility to lipid peroxidation and antioxidant status.

Chemopreventive efficacy of lycopene on 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis.

The chemopreventive efficacy of lycopene on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis was examined using lipid peroxidation, reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione S-transferase (GST) and glutathione reductase (GR) as biomarkers of chemoprevention. Twenty four male Syrian hamsters were divided into four groups of six animals each. The right buccal pouches of the animals in group 1 were painted with a 0.5% solution of DMBA in liquid paraffin three times a week. The animals in group 2 were painted with DMBA as in group 1 and in addition received 2.5 mg/kg body weight lycopene orally three times a week on days alternate to DMBA application. Group 3 animals received lycopene as in group 2. Animals in group 4 received neither DMBA nor lycopene and served as control. The hamsters were killed after an experimental period of 14 weeks. Biochemical measurements were carried out in tumour and normal tissues. All hamsters painted with DMBA alone for 14 weeks developed well-differentiated squamous cell carcinomas. Diminished lipid peroxidation in the oral tumour tissue was accompanied by a significant increase in the levels of GSH, GPx, GST and GR. Administration of lycopene significantly suppressed DMBA-induced oral carcinogenesis as revealed by the absence of carcinomas. The results of the present study suggest that lycopene may exert its chemopreventive effects by modulating lipid peroxidation and enhancing the activities of the enzymes in the glutathione redox cycle.

Cytogenetic and molecular characterization of a congenital mesoblastic nephroma.

A newborn baby boy was diagnosed with the mixed form of congenital mesoblastic nephroma (CMN) representing both classic and cellular histology features in the renal tumor. Additionally, the patient had skin and bone lesions consistent with multifocal involvement of a generalized infantile fibromatosis (IFS). Both skin and bone lesions were distinctly different from CMN and did not represent metastasis. The primary tumor cell line (MCH-MN-1), established from the resected right kidney tumor, had a diploid DNA content. Cytogenetic studies revealed deletion on the long arm of chromosome 3 (q21q24) and duplication on the short arm of chromosome 11 (p15). MCH-MN-1 cells expressed ETV6-NTRK3 gene fusion transcripts, characteristic of cellular and mixed forms of CMNs. The cells had high p21 and low Bax mRNA expression in the reverse transcriptase-polymerase chain reaction (RT-PCR) assay. The high level of proliferative marker (Ki67) mRNA expression correlated well with the pluripotent nature of MCH-MN-1 in tissue culture (cell doubling time = 12.4 h). Our results showed that MCH-MN-1 might be a good model cell line for investigations on mesoblastic nephroma.

Laparoscopic management of abdominal complications in ventriculoperitoneal shunt surgery.

Ventriculoperitoneal (VP) shunts are among the most frequently performed operations in the management of hydrocephalus. Abdominal complications, though rare, are reported to occur in 5-47%. VP shunt obstruction or malfunction leads to raised intracranial pressure, which requires immediate intervention. Recently we have used the laparoscope to manage abdominal complications of VP shunt in two patients. The first patient had hydrocephalus secondary to tubercular meningitis. She developed recurrent intraabdominal cerebrospinal fluid (CSF) pseudocysts, possibly due to subtle peritoneal infection. In the second patient, who developed hydrocephalus following subarachnoid haemorrhage, the lower end of the shunt was malfunctioning due to retraction into the extraperitoneal tissues. The distal end of the VP shunt was revised in both patients with the help of a laparoscopically assisted technique. Thus, a conventional laparotomy, along with its various associated postoperative problems, was avoided without compromising the quality of surgery.