Clinical conferences for physicians: Who sets the agenda?

BACKGROUND: Clinical conferences are generally defined as scheduled events at which practicing physicians themselves present to their colleagues interesting clinical cases, share their new experiences and learn about the latest achievements of medical science and practice. The value of a clinical conference is thought to be in direct communication between physicians, in analysis of topical issues in a given specialty with the aim to improve the quality of care. Speakers based on their own observations and studies reveal the most urgent problems, analyze results and offer potential decisions to their colleagues interested in the same questions. The event format may be different: workshops, highly specialized sections, round tables and seminars with participation of the leading specialists in a given field. These conferences are generally organised by the Ministries and Departments of Health, by leading research and/or educational institutions in the field, by recognised medical centres and other institutions. Recently pharmaceutical companies got actively involved in medical events, acting as sponsors of various scientific conferences and congresses, however threatening the mission of these events [1]. This brings up some uneasy questions: who are the medical conferences for? Who is in charge of setting the conference agenda? Do they contribute to evidence-based medicine; do they contribute to better health? Unfortunately, there is a trend to duplication or multiplication of conferences: various agencies and departments deliver the same conferences, presentations at which are often pre-arranged by pharmaceutical companies and do not have clear scientific novelty, while the conferences themselves have largely transformed into advertising of new pharmaceuticals or new technologies [2]. Pharmaceutical corporations sponsor invited speakers paying for their trips and paying honoraria, organising cocktail parties as part of medical activities. With the help of leading experts with impressive titles serving as speakers at the conferences, pharmaceutical companies are trying to be as close as possible to routine practice of prescribing of certain drugs, manipulating evidence, controlling scientific societies as well as the process of clinical guideline development and publication of research results [3]. The degree of expert involvement depends on their level of influence [4]. OBJECTIVE: We aimed to study how often regular medical practitioners attend these conferences; to analyse who were keynote speakers and where they were coming from; to identify which organizations were responsible for organisation of these conferences and for sending out invitations to these conferences and for disseminating information about them. METHODS: We summarized all the invitations (printed on paper) received by one regular medical practitioner employed with the outpatient clinical of the city of Kazan for the period of two years (2012-2013). RESULTS: During the study period (2012-2013), a regular medical practitioner received 47 printed paper invitations to scientific conferences: 22 in 2012 and 25 in 2013. The conferences were not distributed evenly over the months of the years. November appeared to be the month with the highest density/number of medical conferences: 7 conferences in 2012 and 10 in 2013. If the distribution was even, then we could calculate the number per month dividing the number per year by 9 active months (excluding July, August and September). This resulted in 2.4 and 2.8 conferences per month. Among these studied conferences 4 were organized by public health agencies: invitation tickets were accompanied by the corresponding official order to organise a conference, issued by the Health Department. Noteworthy, that 2 of these conferences were held in conference rooms of the largest hotels of the city. Forty-one out of 47 medical conferences were sponsored by big pharma: either jointly with the major medical higher educational institutions of the city or plainly by pharmaceutical companies. Seventeen conferences were held during official working hours, in the first half of the day. Not only the logo of the pharmaceutical companies was printed on invitation tickets, but there was also an advert of the promoted pharmaceutical brand.Nine conference invitations contained invitation to dinner. In one of the invitations to a conference on neuroscience it was written: "dinner under the unforgettable music". Two conference invitations contained invitation to a lunch. Programs of 20 conferences (which were included) listed guest lecturers, coming from the leading medical universities in Moscow and St. Petersburg. Opinion leaders' involvement: some of the leading experts acted as speakers from 4 to 7 conferences a month in this sample conference invitations package of a regular polyclinic physician. CONCLUSIONS: In 2012-2013 health practitioners were invited to attend medical conferences regularly, at least 2 times a month, with November being the busiest month. The keynote speakers were the opinion leaders from the local medical educational institutions and visitors from Moscow and St. Petersburg; their involvement with the conferences was repetitive. Governmental institutions jointly with big pharma were responsible for organisation of these conferences and attracting audience.Limitations of these observations:Unfortunately, the information on printed-paper conference invitations was not complete because not all tickets have survived. From the interview with the physician we know that in addition to these printed on paper invitations there were many invitations and alerts sent out by e-mail, SMS messages and personal phone calls, making the regularity of these conferences much higher. The physician, who kindly provided this information to us, asked not to be named or thanked in any public presentation of the results of these analyses.

Effects of chloroquine on lysosomes and endocytosis by liver cells in vivo.

1. Chloroquine accumulation in rat liver after a single and repeated drug administration and lysosomal changes resembling some symptoms of lysosomal storage diseases were observed. 2. Repeated chloroquine treatment of rats resulted in increased activity of liver lysosomal enzymes acid phosphatase and beta-galactosidase and a significant enhancement of the activities of cathepsin D and cysteine proteinases were found. 3. No changes in the activity of liver macrophages (as assessed by the colloidal carbon clearance test) or in fluid-phase endocytosis of the marker 125I-polyvinyl-pyrrolidone by hepatocytes in vivo were found.

[Influence of the activation of the immune system cells on the parameters of lipid metabolism in macrophages]. / Vliianie aktivatsii kletok immunnoi sistemy na parametry lipidnogo obmena v makrofagakh.

The influence of tumor necrosis factor a (TNF-alpha) and media, conditioned by activated macrophages and lymphocytes and containing a complex of biologically active compounds (including cytokines), on the parameters of lipid metabolism in macrophages was studied. The addition of recombinant TNF-alpha and immunocompetent cell-conditioned media to mouse peritoneal macrophages culture stimulated labelled oleate incorporation into cholesterol esters and triglycerides, as well as labelled glycerine incorporation into cholesterol esters, but inhibited labelled cholesterol incorporation into cholesterol esters. One of the mechanisms of the influence of activated immunocompetent cells on cholesterol metabolism in macrophages was, supposedly, the stimulation of sphigmomyelinase activity by a complex of anti-inflammatory cytokines produced by these cells on their activation.

[Effect of stimulation and inhibition of macrophage functions on hypercholesterolemia in rats]. / Vliianie stimuliatsii i ingibirovaniia funktsii makrofagov na razvitie giperkholesterinemii u krys.

In this study we investigated the effects of zymosan and prodigiozan, the macrophage stimulators, and GdCl3, a macrophage inhibitor, on blood lipoprotein composition, activities of liver cholesterly ester (CE) metabolising enzymes, incorporation of [14C]cholesterol (C) into bile acids and accumulation and synthesis of CE in peritoneal macrophages (PM) of rats fed with C-enriched diet for 7 days. The increase of number of phagocyte cells quantity in liver and blood colony-stimulating activity in rats pretreated with intravenous injection of zymosan and prodigiozan was accompanied by reduced C content in blood low density and very low density lipoproteins (LDL and VLDL), increase of liver lysosomal CE hydrolase activity (without change of acyl-CoA:C acyltransferase and cytoplasmatic CE hydrolase activities) and incorporation of labeled C into bile acids and decrease of CE formation and accumulation in PM in rats with hypercholesterolemia. In contrast, reduction of phagocyte population in liver caused by intravenous injection of GdCl3 was accompanied by enhancement of C and CE level in blood LDL and VLDL and decrease of lysosomal CE hydrolase activity and incorporation of C into bile acids in liver of C-feeding rats. The data obtained suggest that the stimulation of mononuclear phagocyte system may lead to a decrease of plasma C via activation of LDL and VLDL catabolism and induction of bile acid synthesis in liver.

Basal induction of cytochrome P-450 1A1/1A2 in cells of the liver, small intestinal villi, and lymph nodes in rats.

Rat liver, small intestinal wall, mesenteric, mediastinal, and popliteal lymph nodes of rats were studied by indirect immunoperoxidase method with monoclonal antibodies to cytochrome P-450 1A1/1A2. These cytochrome forms were detected in low concentrations in hepatocytes, macrophages of the small intestinal villi and mesenteric and mediastinal lymph nodes of intact animals. Basal induction of monooxygenase enzymes can be caused by cytochrome inductors entering with air (environmental pollution) or food.

The possibility of cytochrome P450 1A1/1A2 induction in cells of distant lymph nodes of rats after enteral treatment with benzo[a]pyrene.

The mesenteric, mediastinal, and popliteal lymph nodes of rats were studied by indirect immunoperoxidase method using monoclonal antibodies to cytochrome P450 1A1/1A2 after oral treatment with benzo[a]pyrene. These cytochrome forms were detected in monocytes, macrophages, reticular and littoral cells, cell detritus, and liquid contents of the paracortical and medullary sinuses of all studied lymph nodes. The results indicate that exo- and endogenous toxic substances are oxidized not only in the liver, but also in lymph nodes.

Bone mineralization in senescence-accelerated OXYS rats.

We compared age-related changes in the mineral composition of bone tissues in Wistar and senescence-accelerated OXYS rats. The mass concentrations of calcium, phosphorus, and magnesium were measured by atomic emission spectrometry. OXYS rats are characterized by early mineralization of the bone tissue, which peaked by the 6th month of life. Mineralization defects in 12-month-old OXYS rats included accumulation of iron and phosphorus, decrease in the Ca/P ratio, and increase in ash weight. These changes reflected early development and accelerated aging of these animals. Studies of the bone tissue in OXYS rats indicate that these animals can be used for evaluation of the mechanisms of involutional osteoporosis.

Benzo[alpyrene induction of cytochrome P450 1A1/1A2 in the lymph nodes of rats.

Studies of mesenteric lymph nodes of rats by indirect immunoperoxidase method using monoclonal antibodies to cytochrome P450 1A/1A2 after oral dose of benzo[a]pyrene showed the presence of these cytochrome forms in monocytes, macrophages, reticular and litoral cells, cell detritus, and liquid contents of the paracortical zone and medullary substance sinuses. Oxidation of various exo- and endogenous toxins in the lymph nodes was revealed.

Carboxymethylated beta-1,3-glucan inhibits the binding and degradation of acetylated low density lipoproteins in macrophages in vitro and modulates their plasma clearance in vivo.

In atherosclerotic lesions, macrophages are transformed into foam cells accumulating modified low density lipoproteins (LDL) via the scavenger receptor pathway. We have investigated the effects of carboxymethylated beta-1,3-glucan (CMG) on acetylated LDL (AcLDL) metabolism in murine peritoneal macrophages in vitro and upon the clearance of AcLDL by rat liver in vivo. In cultured murine peritoneal macrophages, CMG reduced substantially the AcLDL-induced synthesis of cholesteryl esters, decreased the binding and degradation of [125I]-AcLDL in a dose-dependent manner with complete inhibition at 20-30 nM, but had no effect on the binding and degradation of native [125I]-LDL. In contrast, other polysaccharides studied, namely zymosan lipopolysaccharide, non-modified glucan and mannan Rhodexman, had a slight effect at concentrations significantly exceeding the concentrations of CMG. [125I]-AcLDL injected intravenously into rats was cleared from the blood with a half-life of 3.7 min. About 56 per cent of the label of injected [125I]-AcLDL was recovered in the liver 15 min after administration. Co-injection of the labelled AcLDL with CMG (25 mg kg-1 b.w.) decreased the rate of AcLDL clearance so that the half-life increased to 6.0 min. Injections of CMG (25 mg kg-1 b.w.) 48 and 24 h before the determination increased the rate of [125I]-AcLDL clearance (with a half-life of about 2.3 min) and increased the uptake of AcLDL by the liver. We suggest that CMG competed with AcLDL for scavenger receptors in vitro and in vivo and repeated CMG injections before the measurements of AcLDL resulted in the induction of scavenger receptor function.

Endocytosis by liver cells during suppression of intralysosomal proteolysis.

The lysosomotropic agent chloroquine is widely used as a specific inhibitor of intralysosomal proteolysis in isolated hepatocytes. It was shown that in vitro chloroquine reversibly inhibited purified cathepsins H, B, L in concentrations less than those observed inside lysosomes in vivo. However, administration of high doses of chloroquine to rats (30-50 mg/kg i.p. as a single or repeated injections) was followed by increased cathepsin D and cysteine proteinase activities, as well as other lysosomal enzymes. Chloroquine administration did not induce any changes of carbon particles phagocytosis by liver cells (macrophages); modifications of fluid-phase (125I-PVP uptake) and receptor-mediated endocytosis (125I-asialo-fetuin uptake) were noted. Chloroquine administered in vivo reproduced some symptoms of lysosomal storage diseases (especially during repeated drug administration).

Liver and serum lysosomal enzymes activity during zymosan-induced inflammation in mice.

Liver and serum lysosomal enzymes (acid glucosidases and cysteine proteinases) during zymosan-induced stimulation of MPS or MPR depression induced by GdCl3 have been studied. Zymosan was used as a model for study of inflammation in vivo. The development of inflammation induced by zymosan was followed by increase activity of macrophage activation markers - beta-N-acetylglucosaminidase (NAGlu) and beta-N-acetylgalactosaminidase (NAGal) in liver and serum. There was enhance of liver cysteine proteinases activity. Similar, less prominent (partly) data were obtained during macrophage depression induced by GdCl3.

[Endocytosis by liver cells during stimulation of the mononuclear phagocyte system by yeast polysaccharides]. / Endotsitoz kletkami pecheni pri stimuliatsii sistemy mononuklearnykh fagotsitov drozhzhevymi polisakharidami.

Endocytosis (phagocytosis, fluid-phase- and receptor-mediated endocytosis) by liver cells, lysosomal enzyme activities have been studied during macrophages stimulation by yeast polysaccharides. It was shown that like macrophages stimulator zymosan, yeast polysaccharides cryelan and rhodexman increased the carbon particles phagocytosis. The most effective was intravenous administration of yeast polysaccharides. Compared to rhodexman, the effect of cryelan was more prominent. Macrophages stimulation was followed by suppression of fluid-phase endocytosis by liver cells. Increased activity of cathepsin B was discovered on day 5 after macrophages stimulation (proteinase, most typical for macrophages enzymes).