A randomized controlled trial to evaluate the slow-acting symptom modifying effects of a regimen containing colchicine in a subset of patients with osteoarthritis of the knee

OBJECTIVE

As crystals may contribute to inflammation in osteoarthritis (OA), it is hypothesized that colchicine may have symptom/disease modifying effects in OA. The objective of this study was to evaluate the symptomatic benefit of addition of colchicine to a regimen of intraarticular steroids and piroxicam in patients with knee OA with inflammation.

DESIGN

39 patients with OA of the knee with persisting inflammation, despite at least 2 weeks of piroxicam, were subjected to intraarticular steroid injection and randomly assigned to receive colchicine 0.5 mg twice daily or placebo in a randomized, double blind, placebo-controlled trial over 5 months.

RESULTS

VAS for index knee pain (VAS-pain) and total KGMC score (a modified WOMAC index) at 16 and 20 weeks were significantly better in the colchicine group than the corresponding scores in controls. The benefit persisted on multivariate analysis at 16 weeks (Hotellings T(2)=18.6, F(5,33)=3.3154, P=0.015). The proportion of patients who had 30% or greater response at 16 weeks was significantly higher in the colchicine group in VAS-pain (69% vs 15%) and total KGMC scores (74% vs 45%) and the significance persisted on combined analysis using Mantel-Haenszel test (M-H Risk=5.9, 95% C.I.: 2.08 to 16.73). At 20 weeks, benefit of colchicine therapy was seen on pooled analysis only (M-H risk=3.71, 95% C.I.: 1.07=8.02).

CONCLUSION

The addition of colchicine produced significantly greater symptomatic benefit at 16 and 20 weeks than intraarticular steroid and piroxicam alone in patients with knee OA with inflammation.

Changing perspectives of apheresis in India in the twentieth century

Globally, the last century (20th) has seen many changes in terms of amazing advancements and applications of modern science, medicine, biotechnology and computers. One of the dramatic outcomes of such great inventions and discoveries was that the medical profession got the wonderful tool of immunomodulation and haemapheresis which has changed the outlook of the entire spectrum of immune complex disorders both in terms of the great success in treatment and the rehabilitation from so-called incurable diseases. Additionally this has resulted in a better quality of life and lower morbidity and mortality. Organ transplants have become a reality and immunomodulation plays a pivotal role in their success. India also has tasted this sweet recipe of modern medicine and has imbibed it in its medical culture. India is not only famous for the Taj Mahal and Hawa Mahal (Agra and Jaipur) but also for its brain (of brain drain/otherwise) and betz cells which have brought glories and laurels in the field of medicine, mathematics, engineering, literature, physics and computers, etc. to the native countries and India equally. Apheresis has now invaded the Indian scenario also and there is a growing interest, demand and application for it in the clinical field. But, being a unique country, the problems encountered are also unique. This paper deals with an overview of the changing perspectives of apheresis in India in the 20th century.

Coreflood Studies of Tertiary CO2 Flood in Naturally Fractured Midale Formation in Southeast Saskatchewan

Abstract

The distinctive geology of the Weyburn and Midale reservoirs has important implications for the design of a CO2 injection process for these fields. They are contained within two distinct zones of the Mississippian Carbonate formation; the tight, high-porosity Marly zone sits on top of the low-porosity Vuggy zone. The latter zone has a higher permeability, and is more extensively fractured vertically, than the Marly zone. These geological features result in a relatively unswept Marly zone after waterflooding. The Marly/Vuggy sequence presents an opportunity for a CO2 flood to take advantage of gravity segregation to recover the large remaining oil target in the Marly zone.

A series of coreflood tests were conducted to simulate tertiary CO2 injection in the Marly/Vuggy zones in the Weyburn and Midale reservoirs. Berea cores with different permeabilities were split lengthwise. The halved segments of the core were butted together to represent the Marly and Vuggy zones. Water (in waterflood mode) and CO2 (in tertiary CO2 flood mode) were injected into the bottom high-permeability section of the dualpermeability core. The coreflood results showed that, in the tertiary CO2 flood, CO2 could migrate to and recover the oil from the top low-permeability zone which was poorly swept by the waterflood. Also, the effects on tertiary oil recovery of operating pressure, injection rate, and permeability contrast could be significant.

Introduction

The Weyburn and Midale reservoirs in southeast Saskatchewan hold light and medium gravity oil in fractured, low permeability Midale Beds. These reservoirs are contained within two distinct zones of the Mississippian Carbonate formation: the tight, highporosity Marly zone sits on top of the low-porosity Vuggy zone. The latter zone has a higher permeability, and is more extensively fractured vertically than the Marly zone. These geological features result in a relatively unswept Marly zone after waterflooding.

It is believed that the distinctive geology of these reservoirs has important implications for the design of a CO2 injection process for these fields, i.e., the Marly-Vuggy arrangement of the reservoir offers potential to utilize gravity segregation effects to enhance oil recovery. Numerical analyses(1, 2) of tertiary CO2 injection in these naturally fractured reservoirs showed that CO2 injected into the lower, more permeable Vuggy zone can contact and mobilise a large amount of oil in the Marly, which has remained relatively unaccessed by waterflooding.

A coreflood program was designed at Saskatchewan Research Council (SRC) to address the CO2 injection process in Weyburn reservoir and comparable fields. Laboratory core displacement tests were conducted with a dual permeability split Berea core representing the Marly and Vuggy zones of a reservoir. Some preliminary results reported in a previous paper(3) showed that CO2 injected into the Vuggy zone could rise to the upper Marly zone, and that the potential to recover incremental oil by a tertiary CO2 slug flood is high. After the technique of butting the core halves was improved, the several additional tertiary CO2 coreflood tests reported here were performed with Weyburn reservoir fluid at 63 ° C (reservoir temperature) to confirm the previous finding.

QSAR studies on some antimalarial sulfonamides

Antimalarial activity of a series of sulfonamide derivatives (2,4-diamino-6-quinazoline sulfonamides) was modeled topologically using Wiener (W)-, and Szeged (Sz)-indices. The regression analysis of the data has shown that better results are obtained in multiparametric regressions upon introduction of indicator parameters. Predicting ability of the models was tested by r(2)(cv) values. It was observed that models based on W index gave slightly better results than those in which Sz is involved.

Pediatric hospitalists in Canada and the United States: a survey of pediatric academic department chairs

OBJECTIVES

To document the prevalence and practice patterns of pediatric hospitalists in academic centers in Canada and the United States; to characterize academic pediatric department chairs' definition of the term hospitalist; and to characterize pediatric department chairs' views of the training requirements for pediatric hospitalists.

METHODS

A 14-item questionnaire was sent to all 145 pediatric department chairs from Canada and the United States during the fall of 1998. We defined hospitalists as physicians spending at least 25% of their time in inpatient care.

RESULTS

Of the 145 eligible pediatric chairs, 128 (89%) responded (United States, 111/126; Canada, 14/16; Puerto Rico, 3/3). Ninety-nine (77%) of 128 pediatric chairs either have (64/128) or are planning to have (35/128) hospitalists in their institutions. Within academic programs with hospitalists, 82% of hospitalists currently work on general pediatric wards. Two thirds of hospitalists teach, 50% provide outpatient care, 50% have administrative duties, and 44% conduct research. One hundred eight (84%) of 128 believe that hospitalists should spend at least 50% of their time in inpatient care. Less than one third (30%) of pediatric chairs believe that hospitalists require training not currently provided in residency.

CONCLUSIONS

A large proportion of academic pediatric centers either employed or planned to employ hospitalists in 1998. Pediatric academic department chairs do not see a need for training beyond residency for hospitalists. Further studies should address how pediatric hospitalists affect quality of care, cost, and patient satisfaction.

Stochastic kinetic analysis of the Escherichia coli stress circuit using sigma(32)-targeted antisense

A stochastic Petri net model was developed for simulating the sigma(32) stress circuit in E. coli. Transcription factor sigma(32) is the principal regulator of the response of E. coli to heat shock. Stochastic Petri net (SPN) models are well suited for kinetics characterization of fluxes in biochemical pathways. Notably, there exists a one-to-one mapping of model tokens and places to molecules of particular species. Our model was validated against experiments in which ethanol (inducer of heat shock response) and sigma(32)-targeted antisense (downward regulator) were used to perturb the sigma(32) regulatory pathway. The model was also extended to simulate the effects of recombinant protein production. Results show that the stress response depends heavily on the partitioning of sigma(32) within the cell; that is, sigma(32) becomes immediately available to mediate a stress response because it exists primarily in a sequestered, inactive form, complexed with chaperones DnaK, DnaJ, and GrpE. Recombinant proteins, however, also compete for chaperone proteins, particularly when folded improperly. Our simulations indicate that when the expression of recombinant protein has a low requirement for DnaK, DnaJ, and GrpE, the overall sigma(32) levels may drop, but the level of heat shock proteins will increase. Conversely, when the overexpressed recombinant protein has a strong requirement for the chaperones, a severe response is predicted. Interestingly, both cases were observed experimentally.

Brief information about Siddhasāra Nighantu of Ravigupta

Siddhasāra nighanti, is authored by 'Bauddhācārya Ravigupta'. On the basis of various evidences, its period is considered as 7th century A.D. Actually Ravigupta has written 'Siddhasāra Samhita', the last part of which is known as "Siddhasāra Nighantu'. The second chapter of Siddhasāra Samhita is 'Dravyasamgrahaniya', where 33 Ganas out of 37 Ganas of Suśruta Samhita of 'Dravyasamgrahaniya", chapter have been mentioned. The Dravyas have been described in Paryāya śaily and with 96 Slokas.

Two animal models of retinal degeneration are rescued by recombinant adeno-associated virus-mediated production of FGF-5 and FGF-18

The goal of these experiments was to evaluate the potential of the fibroblast growth factor family members FGF-5 and FGF-18 to rescue photoreceptors from cell death in retinal degenerative disease. Two strains of transgenic rats, expressing either a P23H or an S334ter rhodopsin mutation, were used as model systems. The neurotrophic growth factors were delivered by subretinal injection of adeno-associated virus vectors, driving expression of the genes with a constitutive CMV promoter. Morphological and functional analyses were performed to determine whether FGF-5 or FGF-18 overexpression could ameliorate cell death in the retina. Immunocytochemistry was used to determine the cellular sites of expression of the factors and to test for up-regulation of FGF receptors due to injection. Significant rescue from photoreceptor cell death was found after injections of vectors expressing either FGF-5 or FGF-18 in the animal models. Increased survival of photoreceptors did not produce a significant increase in electroretinographic responses, however, reflecting either trauma due to the surgery or a suppression of signaling due to expression of proteins. Three weeks after injections, both growth factors were localized to the inner and outer segments of photoreceptors, and the receptors FGFR1 and FGFR2 were also found to be up-regulated in these regions. No visible pathological changes were seen in the FGF-5- or FGF-18-treated eyes. These results indicate that the delivery of either FGF-5 or FGF-18 with adeno-associated virus protects photoreceptors from apoptosis in transgenic rat models of retinitis pigmentosa and that the rescue is probably mediated by conventional receptor tyrosine kinase pathways in photoreceptors.

Bioluminescent Mycobacterium aurum expressing firefly luciferase for rapid and high throughput screening of antimycobacterial drugs in vitro and in infected macrophages

The slow growth and highly infectious nature of Mycobacterium tuberculosis is a limiting factor in its use as test organism in high throughput screening for inhibitory compounds. To overcome these problems, use of surrogate strains and reporter genes have been considered. In this study, we have investigated the application of a fast growing nonpathogenic M. aurum expressing firefly luciferase in rapid screening of antituberculosis compounds in vitro and in infected macrophages using bioluminescence assay. The assay is based on luminescence determination using luciferin as substrate. Inhibition of bioluminescence was obtained with frontline antimycobacterial drugs like streptomycin, rifampicin, isoniazid, ethambutol, ofloxacin, and sparfloxacin at their reported MICs. Inhibition could be observed as early as 2 h in vitro and within 24 h in infected macrophages. The system can reliably be used in high throughput screening.

Identification of human lung and skin proteins conjugated with hexamethylene diisocyanate in vitro and in vivo

Diisocyanates are asthma-causing chemicals used in the commercial production of polyurethane. We have previously shown that human lung epithelial cell proteins can become conjugated with hexamethylene diisocyanate (HDI) and may be biologically important in diisocyanate-induced asthma. The objective of this study was to identify specific human lung and skin proteins that become conjugated with diisocyanate after in vitro and in vivo exposure. Following in vitro exposure of human airway epithelial cells (A549), keratin 18, the 78-kD glucose-regulated protein, trans-1, 2-dihyrobenzene-1,2-diol dehydrogenase, and actin were identified as prominent diisocyanate-conjugated proteins through use of a combination of immunocytochemical and mass spectrometric techniques. Following in vivo inhalation of an HDI aerosol, keratin 18 was also identified as the predominant diisocyanate-conjugated protein in human endobronchial biopsy samples, whereas albumin was the predominant diisocyanate-conjugated protein in bronchoalveolar lavage fluid. Keratin was also identified as a predominant diisocyanate-conjugated protein in human skin biopsy samples after epicutaneous exposure to liquid-phase HDI, although the major skin diisocyanate-conjugated protein (56-kD) differed from the predominant lung diisocyanate-conjugated keratin (47-kD). The data from this study identify keratin and other proteins as potential "carriers" for diisocyanates in vivo, and suggest that HDI conjugation of these proteins may play a role in the pathogenesis of diisocyanate-induced asthma.

Effect of Solution Gas in Oil on CO2 Minimum Miscibility Pressure

Abstract

In this study, a rising bubble apparatus (RBA) was used to determine the CO2 MMP for various oils. RBA tests permit direct observation of changes in bubble behaviour and thus offered insight into the phase behaviour for the CO2-reservoir fluid system. The CO2 MMPs were estimated for two Steelman reservoir fluids with a high gas-oil ratio, the partially flashed reservoir fluids, and the dead oils. The composition of solution gas of each partially flashed reservoir fluid was determined and the effects of different gas components were analysed. The MMP was also determined and discussed for Weyburn reservoir fluids which had a low gas-oil ratio with pure and impure CO2. The results of this study demonstrated that the effect of solution gas in oil on CO2 MP could be significant. Furthermore, achieving a miscible CO2 flood (in a reservoir with a Steelman-like reservoir fluid) could be possible at a lower operating pressure than the measured CO2 MMP, by partially depleting the reservoir. This may be the only option for some reservoirs which cannot sustain the relatively high pressure required for achieving miscibility.

Introduction

Carbon dioxide flooding is a proven oil recovery process(1). Over the last decade, carbon dioxide injection has become the leading enhanced oil recovery (EOR) process for light oils(2). CO2 injection can prolong, by 15 to 20 years, the production life of light oil fields nearing depletion under waterflood, and may recover 15 to 25% of the original oil in place. More than 20 years of field experience of CO2 injection has advanced the CO2 technology. CO2 injection can be introduced gradually and use some of the same equipment currently in place for waterflooding.

Saskatchewan's light and medium oil resource, representing nearly 45% of proven reserves, has been on waterflood for over 30 years and is fast approaching its economic limit of production(3). For the light and medium oil reservoirs in Saskatchewan, carbon dioxide or hydrocarbon injection is considered to be the most effective EOR process(4–6). These gases can be injected into the reservoir to develop miscible or immiscible conditions with the oil depending upon the operating pressure. Carbon dioxide is preferred over hydrocarbon gases (e.g., ethane, propane) because it is cheaper, has higher density, and offers environmental benefits by providing storage for CO2 in the reservoir. The Saskatchewan Research Council (SRC) is conducting a comprehensive research program to assess the suitability of miscible CO2 displacement for reservoirs in southeast Saskatchewan and to optimize the field operating procedures.

The first step in determining if a field is a viable CO2 flood candidate is to conduct a screening study to provide a reasonable estimate of CO2 injection performance. The minimum miscibility pressure (MMP) is a key parameter used in the assessment. It has been recognized that the CO2 MMP for a reservoir oil depends on the reservoir temperature, oil composition, and the purity of injected CO2. The minimum miscibility pressure increases with increasing reservoir temperature.

Antisense downregulation of sigma(32) as a transient metabolic controller in Escherichia coli: effects on yield of active organophosphorus hydrolase

Plasmids containing an antisense fragment of the sigma(32) gene were constructed and introduced into Escherichia coli cells. Downregulation of the sigma(32)-mediated stress response was evaluated under heat shock and ethanol stress and during the production of organophosphorus hydrolase (OPH). Northern blot analyses revealed that sigma(32) sense mRNA was virtually undetected in antisense-producing cultures from 5 to 20 min after antisense induction. However, lower-molecular-weight bands were found, presumably due to partial degradation of sigma(32) mRNA. While a >10-fold increase in sigma(32) protein level was found under ethanol stress in the control cultures, antisense producing cultures resulted in a <3-fold increase, indicating downregulation of sigma(32). Correspondingly, antisense synthesis resulted in a decreased level of a sigma(32) regulated chaperone (GroEL) for the first 2 h after induction relative to control cultures without sigma(32) antisense mRNA. The total yield of OPH in the presence of sigma(32) antisense was, on average, 62% of the yield without antisense. However, during sigma(32) antisense production, a sixfold-higher specific OPH activity was observed compared to non-antisense-producing cultures.

The results of cardiac retransplantation: an analysis of the Joint International Society for Heart and Lung Transplantation/United Network for Organ Sharing Thoracic Registry

BACKGROUND

It is well established that repeat heart transplantation has a significantly worse outcome when compared with primary (first time) transplantation. Defining the risk factors for mortality within this group has been difficult due to small numbers of patients at individual centers.

METHODS

All cardiac retransplants performed in the United States and registered in the Joint International Society for Heart and Lung Transplantation (ISHLT)/United Network for Organ Sharing (UNOS) Thoracic Registry were analyzed for demographics, morbidity posttransplantation, immunosuppression, and risk factors for mortality.

RESULTS

The study cohort included 514 patients of which 81% were male with a mean age of 47+/-12 years. Time from primary transplant to retransplantation ranged from 1 day to 15.5 years and more than 50% of the patients underwent retransplantation for chronic rejection. More than 60% of patients were in the intensive care unit at the time of retransplantation and more than 40% of the patients were reported to be on some form of life support (ventricular assist device, ventilator, and/or inotropic therapy). Survival for the entire retransplant cohort was 65, 59, and 55% for 1, 2, and 3 years, respectively, but was substantially lower when the intertransplant interval was short. Conversely, when the interval between primary and retransplantation was more than 2 years, 1 year survival postretransplantation approached that of primary transplantation. Additional independent risk factors for mortality for the retransplant cohort included overall cardiac transplant center volume, the use of a ventricular assist device or ventilator, the patient being in the intensive care unit, and recipient age. The four most common causes of death were infection, primary/nonspecific graft failure, chronic rejection (allograft vasculopathy), and acute rejection.

CONCLUSIONS

The data confirm that repeat heart transplantation is a higher risk procedure than primary transplantation, especially early after the primary heart transplant.

Association of smoking with abnormal exercise heart rate responses and long-term prognosis in a healthy, population-based cohort

BACKGROUND

Cigarette smoking is associated with chronotropic incompetence, defined as an attenuated heart rate response to exercise. The long-term prognostic implications of this association have not been well explored.

SUBJECTS AND METHODS

Adults enrolled in the Lipid Research Clinics' Prevalence Study who had no history of cardiovascular disease and who were not taking beta-blockers were observed for 12 years. Chronotropic incompetence was assessed as the failure to achieve 90% of an age-predicted target heart rate during an exercise test or as a low chronotropic index, a measure of exercise heart rate response adjusted for age, resting heart rate, and physical fitness.

RESULTS

Of the 5,354 eligible participants (mean [+/- SD] age of 44 +/- 10 years; 61% male), 1,931 (36%) smoked cigarettes. Smokers were more likely to have a low chronotropic index (26% versus 16%, odds ratio = 1.8, 95% confidence interval [CI] 1.6 to 2.1) and fail to achieve an age-predicted target heart rate (32% versus 22%, odds ratio = 1.7, 95% CI 1.5 to 2.0). Adjustment for standard cardiac risk factors and physical fitness did not affect these associations. During follow-up, there were 327 deaths. Among subjects without chronotropic incompetence, the relative risk of mortality associated with smoking was moderately increased (hazard ratio = 1.8, 95% CI 1.3 to 2.3); among smokers with chronotropic incompetence, the relative risk of mortality was markedly increased (hazard ratio = 2.7, 95% CI 2.0 to 3.7, P for interaction = 0.02).

CONCLUSIONS

In this large, middle-aged population-based cohort, smoking was associated with chronotropic incompetence, which in turn identified smokers with a particularly high mortality rate.

Dose response to a single intramuscular injection of recombinant adeno-associated virus-erythropoietin in monkeys

BACKGROUND

Anemia is a significant problem in many disease states. Erythropoietin (Epo) has been used in the treatment of anemia associated with numerous chronic diseases. This study investigates the dose-response profiles of a single intramuscular (im) injection of a recombinant adeno-associated virus vector (rAAV) containing the Epo gene with the goal of achieving a sustained elevation of hematocrit (Hct).

METHODS

Cynomolgus (cm) monkeys were given single injections of different doses of rAAV-cm-Epo. The biological effect of Epo gene expression was monitored by determining the Hct levels and circulating hormone levels by ELISA. Antibody to the rAAV capsid protein was also measured over the 41-week period of the experiment.

RESULTS

Epo expression was noted only when 2 x 10(11) or more particles were injected. Epo was noted to be increased as soon as 1 week postinjection and was maximum in 6 to 8 weeks. This level of expression remained constant for nearly 20 weeks. Animals given the highest dose of rAAV developed a higher Hct over the first 8 weeks postinjection than those given an intermediate dose. However, the maximum levels of hemoglobin were the same. There was a weak correlation between amount of rAAV injected and capsid antibody response.

CONCLUSIONS

AAV vectors are able to transduce skeletal muscle and are capable of achieving sustained expression and systemic delivery of a therapeutic protein following a single im administration. Dose responses to rAAV-Epo are achievable, although a threshold inoculum of virus is necessary to produce an effect and the therapeutic window is narrow.