PubMed Health⌕ Search

Biomedical subjects

S De

Publications and source records attributed to S De.

At least 37 records · Page 2Linked to original sources
PubMed2004

Anti-inflammatory and anti-nociceptive activity of the water decoction Desmodium gangeticum.

The water decoction of root and aerial parts of Desmodium gangeticum (Leguminosae) was examined for anti-inflammatory and anti-nociceptive activity in experimental animals. The root and aerial decoction in doses of 5, 10 and 20 mg /kg caused a dose-dependent inhibition of swelling caused by carrageenin equivalent to 14.58-51.02% protection and 14.43-38.67%, respectively, in cotton pellet granuloma. There was a significant increase in analgesio-meter-induced force equivalent to 6.56-67.66% protection and 22.18-73.83% protection in acetic acid-induced writhing. The result establishes the traditional use of water decoction of Desmodium gangeticum codified in Indian System of Medicine.

Analgesics↗
PubMed2004

Myringoplasty using a subcutaneous soft tissue graft.

A retrospective study was performed on patients who underwent myringoplasty using an autologous subcutaneous soft tissue graft over a 5-year period. Details including age, site and size of perforation, grade of surgeon, surgical approach, postoperative dressings, overnight stay, complications and outcome were recorded and analysed. Fifty-two patients underwent myringoplasty using a subcutaneous soft tissue graft. Their ages ranged from 4 to 78 years (median = 36 years). The mean follow-up period was 19 months. Successful closure to give an intact tympanic membrane was obtained in 82.7% of patients. Thresholds improved on pure tone audiometry in 57.1% and deteriorated in only one patient. There was no case of dead ear as a result of surgery. Subcutaneous tissue graft has comparable outcomes with temporalis fascia graft with additional advantages of a smaller incision, minimum dissection and a lower risk of bleeding.

Adolescent↗
PubMed2004

Complicated otitis media caused by Fusobacterium necrophorum.

Fusobacterium necrophorum is implicated as an aetiological agent in a variety of necrotic diseases, such as Lemièrre's syndrome (LS) in humans. LS was initially described as septic thrombophlebitis of the internal jugular vein secondary to an acute oropharyngeal infection. Other primary sources of infection include parotitis, otitis media, sinusitis, odontogenic infection and mastoiditis. In the pre-antibiotic era LS carried a high mortality. This has been reduced as a result of the widespread use of antibiotics, but there is still a definite morbidity and mortality associated with infection with this virulent organism. We report three cases of complicated otitis media caused by Fusobacterium necrophorum. The patients were treated successively with intravenous metronidazole and surgery.

Anti-Infective Agents↗
PubMed2004

Comparative evaluation of cancer chemopreventive efficacy of alpha-tocopherol and quercetin in a murine model.

Chemopreventive efficacy and the mode of action of alpha-tocopherol and quercetin, both known to possess anti-oxidant properties, were evaluated during carcinogenesis in uterine cervix of mice by chronic exposure to methylcholanthrene. Oral administration of alpha-tocopherol and quercetin could reduce the genotoxic effect of the carcinogen as revealed by the micronucleus frequency in vaginal epithelial cells. Both could restrict the progression of dysplastic changes in cervix uteri leading to carcinoma in-situ but the influence of the quercetin was more pronounced. A decrease in lipid peroxides following ingestion of these agents suggests that their chemopreventive action is due to their protective role on DNA damage by free radicals. Increased glutathione and glutathione-s-transferase also indicate their involvement in detoxification. While alpha-tocopherol activated the PBL response towards mitogenic stimulation, quercetin had no such effect.

Animals↗
PubMed2003

Corrosion resistance of polyurethane-coated nitinol cardiovascular stents.

Corrosion of metal stents implanted inside an artery can have two adverse effects: (1) tissue reaction and possible toxic effects from the metal ions leaching out of the stent, and (2) loss of mechanical strength of the stent caused by corrosion. The corrosion resistance of Nitinol (Nickel-Titanium) stents and its modulation with different film thickness of polymer coating was studied against an artificial physiological solution using a Potentiostat/Galvanostat and an electrochemical corrosion cell. The corrosion rate decreased rapidly from 275 microm/year for an uncoated surface down to less than 13 microm/year for a 30 microm thick polyurethane coating. Stainless steel (316L) and Nitinol both contain potentially toxic elements, and both are subject to stress corrosion. Minimization of corrosion can significantly reduce both tissue reaction and structural degradation.

Alloys↗
PubMed2003

Day-case myringoplasty: five years' experience.

A retrospective study of patients who underwent myringoplasty as a day-case procedure in two freestanding day-surgery units during a five-year period was carried out. Their case notes were identified and details including age, site and size of perforation, grade of surgeon, surgical approach, graft material, post-operative dressings, overnight stay, complications, and outcome were noted and analysed. The total number of patients including both children and adults who had myringoplasty as a day case was 144. Of these, 125 patients with 143 procedures were included in this study. Their ages ranged from four to 74 years (mean = 31 years). The perforation size was small in 40 cases, medium in 61 cases, and large/subtotal in 42 cases. The overnight stay rate was 2.7 per cent and this was for immediate post-operative problems such as nausea and bleeding from the wound. The readmission rate for post-operative complications was 2.1 per cent. The follow-up ranged from six months to five years (mean = 19 months). The success rate was 83.3 per cent and thresholds on pure tone audiometry improved in 69.2 per cent of cases. The age of the patient, grade of the surgeon, and graft material did not influence the surgical outcome. There was no case of dead ear as a result of surgery. Myringoplasty can be safely performed in both adults and children as a day-case procedure with low overnight stay and readmission rates. Success rates are comparable to when the procedure is performed on an in-patient basis.

Adolescent↗
PubMed2003

Physically based hybrid approach in real time surgical simulation with force feedback.

This paper describes a novel hybrid-modeling paradigm for the simulation of surgical tool-soft tissue interactions in real time medical simulations using force feedback. A local point collocation-based method of finite spheres is coupled with a global boundary element technique to capture local features of the interaction (e.g., nonlinearities of the soft tissue) without sacrificing global accuracy. The technique is demonstrated using realistic examples.

Computer Simulation↗
PubMed2002

MHC-DRB exon 2 allele polymorphism in Indian river buffalo (Bubalus bubalis).

The polymorphism of the major histocompatibility complex (MHC) class II DRB gene of riverine buffalo (Bubalus bubalis) was studied. Second exon sequences from the buffalo DRB locus, homologous to the cattle DRB3 gene, were amplified and characterized. A combination of single strand conformation polymorphism (SSCP) and heteroduplex analysis (HA) in a non-denaturing gel was used to identify new DRB second exon sequences. SSCP, HA and finally sequencing allowed the identification of 22 MHC-DRB exon 2 alleles from 25 unrelated Indian river buffalo. These are the first river buffalo DRB second exon sequences reported. A high degree of polymorphism in the sequences encoding the peptide binding regions was observed and some amino acid substitutions were found unique to the river buffalo.

Amino Acid Sequence↗
PubMed2002

Expression of bronchodilator response: comparison of four indices.

Several indices have been suggested to express the bronchodilator response but there is no agreement on what is the ideal expression. The forced expiratory volume in I s (FEV1) was measured in 190 patients of bronchial asthma before and after inhalation of 200 micrograms salbutamol. Four different indices of bronchodilator response were calculated. The change in FEV1 was expressed as absolute value (delta FEV1), as a percentage of initial FEV1 (delta FEV1% initial), as a percentage of the predicted normal value (delta FEV1% predicted) and as a percentage of maximum achievable reversibility, i.e. the difference between predicted and initial values (delta FEV1% [predicted-initial]). A significant negative correlation was observed between delta FEV1 initial and initial FEV1% predicted (r = -0.33, P < 0.0001) but not delta FEV1 and initial FEV1% predicted, or between delta FEV1% predicted and initial FEV1% predicted. The values of delta FEV1% [predicted-initial] tended to reach towards infinity as the initial FEV1% predicted approached 100%. delta FEV1% predicted had similar sensitivity but greater specificity than delta FEV1% initial in detecting a true bronchodilator response. It was concluded that being dependent on the initial value, delta FEV1% initial was not an appropriate method to express the bronchodilator response. Although all other methods had limitations, delta FEV1 and delta FEV1% predicted appeared to be better indices.

Adult↗
PubMed2002

Paediatric acute mastoiditis: the Alder Hey experience.

Acute mastoiditis was a common condition in the pre-antibiotic era, but has become rare now with the widespread use of antibiotics. A retrospective study was carried out of patients with acute mastoiditis who were seen at Alder Hey Children's Hospital, Liverpool over a five-year period. Their case records were identified and details of gender, age at presentation, symptoms, signs and clinical management were noted and analysed. Twenty-one patients who presented with acute mastoiditis were identified. The patients' age at presentation ranged from three months to 14 years. Five cases out of 21 (23.8 per cent) were under one year of age. Eighteen cases (85.7 per cent) presented with post-aural swelling while 12 (57.1 per cent) had aural discharge. All patients were treated with intravenous antibiotics and only five patients (23.8 per cent) required surgical intervention in the form of a cortical mastoidectomy with, or without, myringotomy. A significant number of cases can be treated conservatively with intravenous antibiotics. Surgery in the form of cortical mastoidectomy can be reserved for complicated cases and in those in whom conservative treatment has failed.

Acute Disease↗
PubMed2002

Multimodal simulation of laparoscopic Heller myotomy using a meshless technique.

In this work we focus our attention on developing a surgical simulator for performing laparoscopic Heller myotomy using force feedback. A meshless numerical technique, the method of finite spheres, is used for the purpose of physically based, real time haptic and graphical rendering of soft tissues. Localized discretization allows display of deformations in the vicinity of the tool tip as well as interaction forces at high update rates (kHz). Novel cutting algorithms are implemented using point-based representation of anatomical models. Graphical rendering is accomplished by using a recently developed volumetric rendering technique known as splatting.

Computer Graphics↗
PubMed2002

Measurement of in-vivo force response of intra-abdominal soft tissues for surgical simulation.

The lack of data on in-vivo material properties of soft tissues has been a significant impediment in the development of virtual reality based surgical simulators that can provide the user with realistic visual and haptic feedback. As a first step towards characterizing the mechanical behavior of organs, this work presents in-vivo force response of the liver and lower esophagus of pigs when subjected to ramp and hold, and sinusoidal indentations delivered using a haptic feedback device, Phantom, employed as a mechanical stimulator. The results show that pulse significantly affects the reaction forces and that the lower esophagus is 2 to 2.5 times stiffer than the liver.

Abdomen↗
PubMed2001

Lysine(164)alpha of protein farnesyltransferase is important for both CaaX substrate binding and catalysis.

Protein farnesyltransferase (FTase) catalyses the formation of a thioether linkage between proteins containing a C-terminal CaaX motif and a 15-carbon isoprenoid. The involvement of substrates such as oncogenic Ras proteins in tumour formation has led to intense efforts in targeting this enzyme for development of therapeutics. In an ongoing programme to elucidate the mechanism of catalysis by FTase, specific residues of the enzyme identified in structural studies as potentially important in substrate binding and catalysis are being targeted for mutagenesis. In the present study, the role of the positive charge of Lys(164) of the alpha subunit of FTase in substrate binding and catalysis was investigated. Comparison of the wild-type enzyme with enzymes that have either an arginine or alanine residue substituted at this position revealed unexpected roles for this residue in both substrate binding and catalysis. Removal of the positive charge had a significant effect on the association rate constant and the binding affinity of a CaaX peptide substrate, indicating that the positive charge of Lys(164)alpha is involved in formation of the enzyme (E).farnesyl diphosphate (FPP).peptide ternary complex. Furthermore, mutation of Lys(164)alpha resulted in a substantial decrease in the observed rate constant for product formation without alteration of the chemical mechanism. These and additional studies provide compelling evidence that both the charge on Lys(164)alpha, as well as the positioning of the charge, are important for overall catalysis by FTase.

Alkyl and Aryl Transferases↗
PubMed2001

The effect of cross-linking agents on acrylic bone cements containing radiopacifiers.

Poly(methylmethacrylate) PMMA, based cements are the most widely used bone cements in joint replacement surgery. Although, there are some disadvantages in the use of these cements, the clinical success rate is fairly high. Intrinsic radiopacity is difficult to achieve in these cements due to the constituent elements of the PMMA polymer. As radiopacity is an essential requirement, PMMA bone cements have been rendered radiopaque by blending heavy metal ion salts, which tend to adversely affect the mechanical and biological properties of the bone cement. In this study, dimethacrylate cross-linking agents were added to the monomer phase in order to generate a cross-linked matrix, with barium sulphate as a radiopaque agent. The results suggest that the mechanical properties can be improved or retained with the addition of such cross-linking agents.

Acrylates↗
PubMed2001

The accuracy of MEDLINE and Journal contents pages for papers published in Clinical Otolaryngology.

MEDLINE is widely used as a source for identifying and reviewing medical journal literature. Its accuracy is generally taken for granted, as is that of the contents pages published by the journals themselves. In this study of citation accuracy we examined the articles published in Clinical Otolaryngology and Allied Sciences from 1976 to 1998. The entries in MEDLINE were compared with the entries in the Journal's contents pages, and with the actual articles. Of 1651 articles published in the journal, one was omitted from MEDLINE and 25 (1.5%) were incorrectly cited, while 88 (5.3%) were incorrectly cited in the contents pages. Twenty-one (84%) of the errors in MEDLINE involved names of authors. Apart from incomplete retrieval of information for practice and research, errors could result in an author not getting credit for publications.

Abstracting and Indexing↗
PubMed2001

Metastatic malignant melanoma of the larynx.

Metastatic malignant melanoma of the larynx is considered to be extremely rare by most authors. This paper describes a 78-year-old patient, previously treated for cutaneous malignant melanoma and intestinal fibrosarcoma, who presented with stridor due to a metastatic melanoma in the larynx. It was a pedunculated lesion and surgical excision of the lesion was accomplished with a tonsillar snare. This paper further discusses the evolving history, diagnosis and treatment of this metastatic tumour, and reviews the literature regarding previously reported cases.

Aged↗
PubMed2001

A meshless numerical technique for physically based real time medical simulations.

This work introduces, for the first time, a meshless modeling technique, the method of finite spheres, for physically based, real time rendering of soft tissues in medical simulations. The technique is conceptually similar to the traditional finite element techniques. However, while the finite element techniques requires a slow mesh generation process, this new technique has significant potential for multimodal medical simulations of the future since it does not use a mesh. Several examples are presented showing the effectiveness of the scheme.

Computer Graphics↗