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Biomedical subjects

P Nandi

Publications and source records attributed to P Nandi.

At least 19 recordsLinked to original sources

Managing severe lower limb spasticity in multiple sclerosis: does intrathecal phenol have a role?

OBJECTIVE: Established treatment options for managing severe lower limb spasticity and associated pain are of limited value in people with advanced multiple sclerosis (MS). This has resulted in a resurgence of the use of lumbar intrathecal phenol injection (IP). The aim of this study was to investigate the authors' experience with IP. METHODS: This observational study collected cross sectional data from patients with progressive MS who received IP for severe lower limb spasticity. Data from 25 patients were collected prospectively before and after treatment. In 15 cases the data related to the first treatment and in 10 to serial injections. Outcome measures collected included the Ashworth scale, a spasm frequency scale, a pain rating score, and the percentage achievement of practical goals. RESULTS: After injection, all patients demonstrated reduced lower limb tone bilaterally. After the initial injection there was significant improvement on the targeted as compared with the non-targeted side (Wilcoxon rank p=0.003), while no difference in the degree of improvement between the targeted and non-targeted side was seen after serial injections (Wilcoxon rank p=0.731). Twenty four patients were easier to position and 21 had a reduction in their spasm frequency and intensity. Eleven patients with pain reported benefit. Carers found washing and dressing easier in 16 patients and improved safety when using the hoist in 10. Six patients had recurrence of skin breakdown and five patients reported transient adverse changes in their bowel function. CONCLUSIONS: IP can reduce lower limb tone bilaterally after both initial and serial injections. This is most noticeable on the targeted side after initial injection. IP can reduce spasms and pain, leading to improvements in care and overall comfort. IP is an effective treatment option in the management of severe spasticity. Documented selection criteria are essential.

Activities of Daily Living↗

The prion protein has DNA strand transfer properties similar to retroviral nucleocapsid protein.

The transmissible spongiform encephalopathies are fatal neurodegenerative diseases that are associated with the accumulation of a protease-resistant form of the cellular prion protein (PrP). Although PrP is highly conserved and widely expressed in vertebrates, its function remains a matter of speculation. Indeed PrP null mice develop normally and are healthy. Recent results show that PrP binds to nucleic acids in vitro and is found associated with retroviral particles. Furthermore, in mice the scrapie infectious process appears to be accelerated by MuLV replication. These observations prompted us to further investigate the interaction between PrP and nucleic acids, and compare it with that of the retroviral nucleocapsid protein (NC). As the major nucleic acid-binding protein of the retroviral particle, NC protein is tightly associated with the genomic RNA in the virion nucleocapsid, where it chaperones proviral DNA synthesis by reverse transcriptase. Our results show that the human prion protein (huPrP) functionally resembles NCp7 of HIV-1. Both proteins form large nucleoprotein complexes upon binding to DNA. They accelerate the hybridization of complementary DNA strands and chaperone viral DNA synthesis during the minus and plus DNA strand transfers necessary to generate the long terminal repeats. The DNA-binding and strand transfer properties of huPrP appear to map to the N-terminal fragment comprising residues 23 to 144, whereas the C-terminal domain is inactive. These findings suggest that PrP could be involved in nucleic acid metabolism in vivo.

Capsid↗

The prion protein has RNA binding and chaperoning properties characteristic of nucleocapsid protein NCP7 of HIV-1.

Transmissible spongiform encephalopathies are fatal neurodegenerative diseases associated with the accumulation of a protease-resistant form of the prion protein (PrP). Although PrP is conserved in vertebrates, its function remains to be identified. In vitro PrP binds large nucleic acids causing the formation of nucleoprotein complexes resembling human immunodeficiency virus type 1 (HIV-1) nucleocapsid-RNA complexes and in vivo MuLV replication accelerates the scrapie infectious process, suggesting possible interactions between retroviruses and PrP. Retroviruses, including HIV-1 encode a major nucleic acid binding protein (NC protein) found within the virus where 2000 NC protein molecules coat the dimeric genome. NC is required in virus assembly and infection to chaperone RNA dimerization and packaging and in proviral DNA synthesis by reverse transcriptase (RT). In HIV-1, 5'-leader RNA/NC interactions appear to control these viral processes. This prompted us to compare and contrast the interactions of human and ovine PrP and HIV-1 NCp7 with HIV-1 5'-leader RNA. Results show that PrP has properties characteristic of NCp7 with respect to viral RNA dimerization and proviral DNA synthesis by RT. The NC-like properties of huPrP map to the N-terminal region of huPrP. Interestingly, PrP localizes in the membrane and cytoplasm of PrP-expressing cells. These findings suggest that PrP is a multifunctional protein possibly participating in nucleic acid metabolism.

5' Untranslated Regions↗

Dietary chemoprevention of clastogenic effects of 3,4-benzo(a)pyrene by Emblica officinalis Gaertn. fruit extract.

Dietary supplementation with extract of fruit of Emblica officinalis Gaertn. (a rich source of vitamin C) to mice in vivo significantly reduced the cytotoxic effects of a known carcinogen, 3,4-benzo(a)pyrene. Age-matched Swiss albino mice were fed by gavaging the fruit extract daily for 28 days. From day 9, one dose of the carcinogen was given on alternate days up to a total of eight doses. On day 29, all mice were transferred to normal diet. Control sets received the extract alone, the carcinogen alone and olive oil alone. All mice were sacrificed at 12 weeks and 14 weeks after the end of the experiment. Chromosome preparations were made from bone marrow after the usual colchicine-hypotonic-fixative-air drying-Giemsa staining schedule. Cytogenetic end points screened were the frequencies of chromosomal aberrations and of damaged cells induced. The cytotoxic effects were significantly lower in the mice given the fruit extract with the carcinogen than in those given the carcinogen alone.

Animals↗

Prediction of rib fracture injury outcome by an artificial neural network.

Outcome-based therapy is becoming the standard for assessing patient care efficacy. This study examines the ability of an artificial neural network to predict rib fracture injury outcome based on 20 intake variables determined within 1 hour of admission. The data base contained 580 patient records with four outcome variables: Length of hospital stay (LOS), ICU days, Lived, and Died. A 522-patient training set and a 58-patient test set were randomly selected. Nine networks were set up in a feed-forward, back-propagating design with each trained under different initial conditions. These networks predicted the test set outcome variables with an accuracy as high as 98% at the 80% testing level. Internal weight matrix examination indicated that age, ventilatory support, and high trauma scores were strongly associated with both ICU days and mortality. Being female, injury severity, and injury type were associated with increased LOS. Smoking and rib fracture number were low-level predictors of the four outcome variables.

Adolescent↗

The Sparklet carbon dioxide resuscitator.

The use of carbon dioxide in resuscitation was advocated in the 1920s and 1930s. A device, the Sparklet Resuscitator, was marketed to allow the administration of carbon dioxide gas. This piece of equipment is described and the indications for its use in resuscitation reviewed. The use of carbon dioxide appeared to have a degree of support and success as a 'universal' aid to resuscitation.

Carbon Dioxide↗

Bovine rotavirus segment 5 protein expressed in the baculovirus system interacts with zinc and RNA.

The cDNA sequence of genomic segment 5 of bovine rotavirus (RF strain) has been inserted into baculovirus transfer vectors, downstream of the polyhedrin promotor. Recombinant baculoviruses containing gene 5 were selected and the protein was expressed to high yields in Spodoptera frugiperda cells. The recombinant protein was inoculated into rabbits and mice to produce specific hyperimmune antisera. The polyclonal antiserum reacted with a protein in rotavirus-infected MA104 cells and with a protein translated in vitro. This serum was also used to confirm that the gene 5 protein is not a structural protein. Recently, the gene 5 product has been predicted to be a zinc finger protein and reported to contain a highly conserved arrangement of cysteine residues; here, we demonstrate that the recombinant gene 5 protein binds zinc and is an RNA-binding protein as are several other zinc finger proteins.

Amino Acid Sequence↗

Interaction of rotavirus particles with liposomes.

We have studied the interactions of purified viral particles with liposomes as a model to understand the mechanism of entry of rotavirus into the cell. Liposomes, made from pure as well as mixed lipids, that contained encapsulated self-quenching concentrations of the fluorophore carboxyfluorescein (CF) were used. Rotavirus-liposome interactions were studied from the fluorescence dequenching of CF resulting from its release to the bulk solution. Purified infectious double-shelled virus particles induced a concentration- and temperature-dependent release of CF. The rate and extent of CF release was maximum between pH 7.3 and 7.6. The removal of outer structural proteins VP4 and VP7 from virus, which results in the formation of single-shelled particles, prevented virus interaction with liposomes. Rotavirus particles with uncleaved VP4 did not interact with liposomes, but treatment in situ of these particles with trypsin restored the interaction with the liposomes and resulted in CF dequenching. Our data support the view that rotavirus enters the cell through direct penetration of the plasma membrane. In contrast, adenovirus, the only other nonenveloped virus studied by this method, shows the optimum rate of marker release from liposomes at around pH 6 (R. Blumenthal, P. S. Seth, M. C. Willingham, and I. Pastan, Biochemistry 25:2231-2237, 1986). The interaction between rotavirus and liposomes is sensitive to specific divalent metal ions, unlike the adenovirus-liposome interaction, which is independent of them.

Animals↗

Thermogenesis after surgery: effect of perioperative heat conservation and epidural anesthesia.

Body temperature, respiratory gas exchange, and plasma catecholamines were determined before and after surgery in three groups [control (C), warmed (W), and epidural (E) who received local anesthetic at T4-S5 dermatomes during and for 24 h after surgery] of patients undergoing colonic surgery under general anesthesia. At the end of surgery, group W were nursed in an ambient temperature of 28-30 degrees C, whereas the others were at 20-23 degrees C for a period of 24 h. Core (Tc) and dorsal hand temperature decreased during surgery in both C and E (P less than 0.05) but not in W. After surgery, Tc increased similarly in C and E and by a smaller amount in W. Plasma catecholamine concentrations increased significantly in C and W but not in E (P less than 0.001), with the greatest response occurring in C. Postoperative oxygen consumption and carbon dioxide production exceeded preoperative values (P less than 0.01) in C but not in W or E. After surgery, plasma albumin fell and C-reactive protein increased similarly in all three groups. Thus body heat conservation or epidural blockade attenuates or abolishes the rise in plasma catecholamines and oxygen consumption postoperatively but does not prevent the increase in Tc or the acute phase protein response.

Anesthesia, Epidural↗

Is hysteria on the wane? A community survey in West Bengal, India.

A field survey was conducted in two villages--Gambhirgachi and Paharpur--in 1972. The survey was repeated after 10 years in the former village and after 15 years in the latter one. The second survey showed very little change in the rate of total mental morbidity. The rate of prevalence of hysteria declined significantly in both villages. In Gambhirgachi the rate of hysteria dropped from 16.9 to 4.6 per 1000 in 10 years, and in Paharpur it dropped from 32.3 to 2.05 per 1000 in 15 years.

Adolescent↗

Diffusion properties of clathrin on the surface of isolated mouse liver nuclei by the fluorescence recovery after photobleaching technique.

Clathrin labeled with eosin maleimide showed physicochemical properties similar to the native clathrin. The diffusion coefficients of clathrin protomers and cages measured at 20 degrees C by the fluorescence recovery after photobleaching technique (FRAP) were found equal to (9 +/- 1).10(-8) cm2.s-1 and (3 +/- 0.4.10(-8) cm2.s-1, respectively. After incubation with isolated mouse liver nuclei suspended in an aqueous buffer, FRAP measurements showed that 78% of clathrin was immobilized on the nuclear surface. This immobile fraction might correspond to aggregates of molecules resembling coated pits. The mobile fraction had a diffusion coefficient of 2.5.10(-9) cm2.s-1 which was reduced seven times when the suspension medium of the nuclei contained 50% sucrose, showing that the aqueous phase exerted an important drag on the clathrin molecules motion diffusing on the nuclear surface.

Animals↗

Lipothymoma.

Two cases of asymptomatic lipothymoma, discovered on "routine" roentgenograms of the chest, are presented. Thirty well-documented reports of this tumor in the English literature are reviewed. The pertinent points concerning this rare clinicopathological entity are summarized and discussed.

Adolescent↗

Incidence of postoperative deep vein thrombosis in Hong Kong Chinese.

Postoperative deep vein thrombosis is considered to be rare in Chinese. The 125I-labelled fibrinogen test was used to determine the true incidence of postoperative deep vein thrombosis in Chinese. Deep vein thrombosis was found in 2.6 per cent, a very low incidence compared with Caucasian series.

Adult↗

Early intracardiac repair of large ventricular septal defects with conventional cardiopulmonary bypass and moderate hypothermia.

With the use of conventional cardiopulmonary bypass and moderate hypothermia, primary intracardiac repair of large ventricular septal defects was performed in 30 children below the age of two years. All babies were falling to thrive and suffered from cardiac failure resistant to medical therapy, or had evidence of early pulmonary vascular disease. Two patients died after the operation, giving an operative mortality of 6.7%. Twenty-eight survivors have been followed for periods of one month to two and a half years. All are thriving and have normal or mildly enlarged hearts on their chest skiagrams. Primary intracardiac repair of large ventricular septal defects can be performed in infants and small children with a low operative risk when the standard cardiopulmonary bypass technique is being used.

Cardiopulmonary Bypass↗

Recurrent spontaneous pneumothorax; an effective method of talc poudrage.

Between January 1977 and December 1978, 24 patients with recurrent or chronic spontaneous pneumothorax were treated in the Hong Kong University Cardiothoracic Centre at Grantham Hospital by talc pleurodesis. Talc poudrage had been carried out under local infiltration anesthesia by a technique that utilizes the Venturi principle and the help of an oxygen injector, used normally for ventilating a patient during bronchoscopy with a rigid bronchoscope. By using this method of poudrage, a uniform application of the powder over the whole pleural surface can be achieved and successful pleurodesis can be obtained in all patients under local anesthesia.

Adult↗