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RATIONALE: Evidence suggests that differential rearing influences the function of a receptor subtype critical for maintaining glutamate homeostasis. Maintaining homeostatic glutamatergic function may be an important protector against drug abuse. OBJECTIVE: This study sought to determine if differential rearing influences the function of a receptor critical for glutamate homeostasis, which could in turn affect rates of amphetamine self-administration. METHODS: Rats were assigned to enriched (EC), isolated (IC), or standard (SC) conditions. After rearing for 30 days, rats were trained to lever press for sucrose reinforcement before the implantation of indwelling jugular catheters. After reaching stable responding for amphetamine (0.03 or 0.1 mg/kg/infusion), rats were injected with five doses (0, 0.3, 1.0, 3.0, and 5.0 mg/kg) of the mGluR5 antagonist, 3-((2-methyl-1,3-thiazol-4-yl)ethynyl) pyridine hydrochloride (MTEP), 30 min before self-administration sessions. Following fixed-ratio (FR-1) testing, rats were administered identical doses of MTEP on a progressive-ratio (PR) reinforcement schedule. RESULTS: MTEP (3.0 mg/kg) attenuated FR-1 self-administration (0.03 mg/kg/infusion) in IC rats. MTEP also dose-dependently attenuated amphetamine self-administration (0.1 mg/kg/infusion) during FR-1 and PR sessions, with 5.0 mg/kg MTEP attenuating amphetamine self-administration in IC and SC rats and 3.0 mg/kg MTEP attenuating amphetamine self-administration in EC and SC rats. PR results also revealed that IC rats not treated with MTEP were more motivated to self-administer the higher dose of amphetamine. CONCLUSIONS: These results suggest that the mGlu5 receptor mediates differences in drug-taking behavior among differentially reared rats. Isolation also decreased sensitivity to MTEP, suggesting that environmental factors alter glutamate homeostasis which subsequently affects sensitivity and motivation to self-administer amphetamine.

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BACKGROUND: Acupuncture is a promising treatment approach in patients with chronic low back pain (cLBP) but little is known about the quality of acupuncture in randomized controlled trials (RCT) of acupuncture cLBP. - OBJECTIVE: To determine how international experts (IES) rate the quality of acupuncture in RCTs of cLBP; independent international validation of the Low Back Pain Acupuncture Score (LBPAS). METHODOLOGY: Fifteen experts from 9 different countries outside China were surveyed (IES). They were asked to read anonymized excerpts of 24 RCTs of cLBP and answer a three-item questionnaire on how the method of acupuncture conformed to 1) Chinese textbook standards, 2) the expert?s personally preferred style, and 3) how acupuncture is performed in the expert?s country. Likert scale rating, calculation of the mode for each answer, and Spearman?s rank correlation coefficient between all three answers and the LBPAS were calculated. RESULTS: On comparison with Chinese textbook standards (question 1), 6 RCTs received a good rating, 8 trials a fair and 10 trials a poor or very poor rating. 5 of the 6 trials rated good, received at least a good rating also in question 2 or 3. We found a high correlation of 0.85 (p<0.0001) between the IES and LBPAS ratings for question 1 and question 2, and a correlation of 0.66 (p<0.0001) for question 3. CONCLUSION: The international expert survey (IES) revealed that only 6 out of 24 (25%) RCTs of acupuncture for cLBP were rated "good" in respect to Chinese textbook acupuncture standards. There were only small differences in how the acupuncture quality was rated in comparison to Chinese textbook acupuncture, personally preferred and local styles of acupuncture. The rating showed a high correlation with the Low Back Pain Acupuncture Score LBPAS.

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PURPOSE: To compare chromosomal aberrations in peripheral lymphocytes of Wismut uranium miners (WUM) and Ruhr coal miners (RCM). MATERIALS AND METHODS: Peripheral lymphocytes from 66 WUM and 29 RCM were cultured and analysed for structural chromosomal aberrations in Giemsa-stained M1 metaphases. Cytogenetic data from 23 male white-collar workers from public services were used as a historical control group. RESULTS: The frequencies of chromosomal aberrations and sister chromatid exchanges in WUM and RCM were quite similar. Compared with public services workers, WUM and RCM had significantly higher frequencies of chromosomal aberrations. CONCLUSIONS: Chromosomal aberrations in WUM are not induced by radioactive particles inhaled during underground mining but as in RCM rather result from factors such as age, lifestyle, illnesses, medications and diagnostic irradiations.

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Outcome evaluations are of primary concern in contemporary medical practice. Questionnaires are being used increasingly to provide input data for such outcomes evaluation. This study comprised 50 primary total hip arthroplasties in 36 patients who had undergone the procedure at least 12 months before enrollment. Each patient completed a self-report Harris Hip Score (HHS) 30 days before a formal evaluation by an independent orthopaedic surgeon that included a HHS. Comparison was made between the completed responses to the individual items on the self-report HHS and surgeon-assessed HHS. Concordance of item response and kappa statistic were calculated. Overall the self-report and surgeon-assessed HHS showed excellent concordance. The results of this study support the use of the HHS as a self-report instrument.

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This study was performed to investigate the effect of cholesterol content, surface charge and sterical stabilization on the physico-chemical properties of liposomes prepared from the cancerostatic alkylphospholipid, octadecyl-1,1-dimethyl-piperidino-4-yl-phosphate (D21266), and their relationship to in vitro cytotoxicity. Stable incorporation of OPP into liposomes was found to be highly dependent on the cholesterol content. 31P-NMR spectroscopy as well as analysis of the lipid composition of OPP-containing liposome formulations revealed an increase in the amount of non-liposome-associated, micellar OPP as the cholesterol content decreased. The fraction of non-liposome-associated OPP constituted about 10% of total OPP when cholesterol was present in equimolar amounts (45.5/45.5 mol %) and increased to approximately 30% at a twofold excess of OPP over cholesterol (58.8/29.4 mol %). In monolayer incorporation studies it was shown that the existence of an increasing micellar pool of lipids leads to increased lipid transfer into the target monolayer. Liposome formulations containing more OPP than cholesterol were also found to display greater cytotoxicity. However, all liposome formulations were less cytotxic than pure (micellar) OPP. Cytotoxicity was not affected by the incorporation of N-methoxy-polyethyleneglycol2000-phosphoethanolamine, a lipid that is known to reduce liposome uptake into phagocytic cells. The results demonstrate that the increase in cell toxicity correlates with the increase in non-liposome-associated, micellar OPP, which can readily exchange into cellular membranes.

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As a part of a prospective study of 20 patients with previous pelvic surgery, the efficacy of using a 2/3 mm dilatable STEP device (InnerDyne, Inc., Sunnyvale, USA) for the first insertion in the area below the left costal border was tested, using 2 or 3.3 mm minilaparoscopes (Storz). Despite the high incidence of periumbilical omental and bowel adhesions (55%), no complications were observed in any of the 20 patients with previous pelvic surgery. Herewith could be confirmed that the use of a minilaparoscope in the area below the left costal border represents in high risk patients a safe and minimally invasive method for preventing or reducing the number of trocar-related injuries during first trocar insertion. In combination with the use of 2/3 mm disposable STEP-trocars if clinically required an atraumatic dilation and safe insertion of reusable 5 mm, 10 mm or 12 mm trocars is enabled.

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Conventional and sterically stabilized liposomes derived from phosphatidylcholine or the antitumor agents, hexadecylphosphocholine and octadecyl-(1,1-dimethyl-4-piperidino-4-yl)-phosphate, as bilayer forming constituents, containing bleomycin, were developed and tested. Liposomal encapsulation of bleomycin enhanced strongly the antitumor activity against P388 leukemia and the Lewis lung carcinoma. This effect was clearly dependent on the size and lipid composition of the bleomycin-containing liposomes. The therapeutic effects were nearly equal for liposomal and free bleomycin in the B16 melanoma. The partial replacement of phosphatidylcholine by alkylphospholipids and the inclusion of polyethylene glycol modified lipids for sterical stabilization did not further improve the therapeutic efficacy but increased, in some cases, the toxicity of liposomes. Bleomycin-induced lung injury was not observed if liposomal bleomycin was administered.

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Metabolic activity of the polymorphic N-acetyltransferase (NAT2) is determined by the mutation pattern of the NAT2 gene. This results in interindividual differences in the metabolic capacity (the phenotype), with continuous distribution of the activities rather than qualitative distinction between rapid and slow acetylators. To determine whether the phenotype might be predicted solely from the mutation pattern of NAT2, quantitative relationships were calculated between mutation patterns of the NAT2 gene and the phenotype of NAT2 assessed either in vitro or in vivo. Healthy volunteers were examined for the velocity at which they metabolized sulfamethazine, and human liver cytosols were measured for NAT2 enzymatic activity, obtaining in vivo and in vitro metabolic phenotype, respectively. Typing of the NAT2 gene was performed by polymerase chain reaction, restriction fragment length analysis, or allele-specific polymerase chain reaction. Multiple linear regression analysis provided quantitative relationships between allelic pattern and the NAT2 activities measured in vivo and in vitro. Estimates showed the influence of particular allelic configurations on enzyme activity in vitro and the extent of acetylation of the probe drug in vivo, resulting in a strict gene-dose effect. Comparison of in vitro results with in vivo phenotyping figures showed a high degree of correspondence, indicating that the one is the reflection of the other.

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Liposomes prepared from the cancerostatic octadecyl-(N,N-dimethylpiperidino-4-yl)-phosphate (OPP) were investigated in order to characterize the influence of composition on cytotoxicity and to minimize side effects on the immune system. Differently composed liposomes with respect to charge, cholesterol content and steric stabilization were used. Fluorescence measurements and the MTT assay were applied to investigate the effect of uptake and cytotoxicity, respectively, on J774 mouse macrophages and MT1 human breast cancer cells in vitro. Because of their endocytotic capability, uptake was generally higher for macrophages compared with tumour cells. OPP liposomes, which are negatively charged, cholesterol-poor and sterically stabilized, showed the lowest total and internal uptake by both cell lines. On the other hand, these liposomes were also the most cytotoxic ones for both cell lines investigated, with an inhibitory concentration of between 50 and 80 microM. Cytotoxicity does not correlate with cellular uptake and is most likely caused by other mechanisms. The results demonstrate that cancerostatic liposomes have composition-dependent toxic effects on macrophages which have to be seriously considered. For therapeutic experiments in vivo liposomes should be negatively charged and sterically stabilized and composed of OPP and cholesterol in a molar ratio of approximately 1.

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Diabetes mellitus affects approximately 16 million people in the United States. Despite the publication of multiple guidelines, the delivery of care has not substantially changed. This article describes a program at Advocate Health Care to improve the delivery of care to individuals with Type 2 diabetes mellitus in an ambulatory setting. Using a variety of continuous quality improvement tools, this project enhances partnerships between patients and health care providers.

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The pharmacokinetics of free and different liposomal formulations of hexadecylphosphocholine (HPC) was investigated in tumor-bearing (human mammary tumor MaTu) and tumor-free mice after intravenous and intraperitoneal administration. The levels of HPC were evaluated at different times in serum, normal tissues, and tumor. The purpose was to test the hypothesis that the enhanced therapeutic efficacy of sterically stabilized HPC liposomes in comparison to conventional vesicles and free HPC is due to its pharmacokinetics. Conventional non-compartmental pharmacokinetic analysis and an elaborate three- and four-compartmental model were used for explaining the experimental data. The serum levels of HPC obtained with sterically stabilized liposomes were only consistently higher in comparison to conventional vesicles and free HPC in the first 4 h. In the xenografted MaTu carcinoma, the differences of the HPC content between the different groups are unexpectedly low and do not reflect the high therapeutic activity [5] of sterically stabilized HPC liposomes. Detailed analysis shows that the liposomally encapsulated drug displays a modified pharmacokinetic behavior, which may also involve lymphatic absorption of the liposomal drug.

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Liposomes from octadecyl-(1,1-dimethyl-4-piperidino-4-yl)-phosphate (OPP), a new alkylphospholipid derivative with an improved cancerostatic activity, were prepared for the first time and the activity in vitro and in vivo was characterised. The formation of liposomes (MLV, SUV and LUVET) differing in cholesterol content, charge, and sterical stabilisation is possible without serious problems, despite the lysolipid-like structure of the OPP. Liposomes with a low amount of cholesterol and with PEG2000DSPE-coating were the most stable OPP liposomes, both in buffer and in serum. The cytotoxicity of micellar or liposomal OPP against breast cancer cell lines in vitro was in the range of 20-60 microM. The cytotoxicity of the liposomal formulation was inversely related to the content of cholesterol, whereas the sterical stabilisation and/or the incorporation of a positive charge had only a very moderate modulating effect on the inhibition of cell proliferation. The strongest antitumour effect on the xenotransplanted breast cancer MT-3 in vivo was obtained with sterically stabilised OPP liposomes with low CH content. The beneficial therapeutic effect of these liposomes was accompanied by better tolerance and a significant inhibition of haemolysis compared to micellar OPP.

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New sterically stabilized liposomes derived from the antitumor agent hexadecylphosphocholine with reduced uptake by the mononuclear phagocyte system and improved antitumor activities were developed and tested. The bilayer of such sterically stabilized liposomes consists of hexadecylphosphocholine, cholesterol and polyethylene glycol-linked phosphoethanolamine. The measurement of carbon clearance in mice shows that these stabilized liposomes, in contrast to conventional alkylphosphocholine liposomes, are not largely engulfed by the mononuclear phagocyte system. Their therapeutic activity on experimental human breast carcinomas MaTu. MT-1 and MT-3 was tested in nude mice. Especially in the MaTu models the sterically stabilized hexadecylphosphocholine liposomes resulted in significantly reduced tumor growth in comparison to conventional hexadecylphosphocholine liposomes or free hexadecylphosphocholine. The enhanced therapeutic efficacy of sterically stabilized hexadecylphosphocholine liposomes is probably related to the extended circulation time of the formulation and its accumulation in tumors.

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A serious problem using liposomes for therapeutic purposes is the fast removal from blood circulation by components of the reticuloendothelial system (RES) most likely after opsonization of the vesicles. This study was performed to quantify the reduction in macrophage uptake in vitro of sterically stabilized liposomes (PEG-liposomes) prepared from hexadecylphosphocholine, cholesterol and poly(ethylene glycol2000) distearoylphosphoethanolamine (PEG2000DSPE) for the first time. The uptake was determined using HPC-liposomes of different defined size (125, 250 and 1000 nm) without and with sterical stabilization by incorporating 5 mol% of PEG2000DSPE. HPTS was used as fluorescence marker allowing the discrimination between general uptake and the part of liposomes internalized into the low pH-compartment (Daleke, L.D., Hong, K. and Papahadjopoulos. D. (1990) Biochim. Biophys. Acta 1024, 352-366). Liposomal uptake by J774 mouse macrophage-like cells was time-dependent. Both the uptake and internalization were clearly reduced for PEG-liposomes compared to plain liposomes. Sterical stabilization reduced the general uptake of liposomes in vitro by more than 50% and the internalization by about 50-60%. PEG-liposomes additionally showed a delay in internalization into the macrophages during the first 6 h. Size of used liposomes had only a minor influence on liposomal uptake but highest concentration of lipid was found for large multilammelar vesicles (MLV). The fixed aqueous layer thickness (FALT) was determined by zeta potential measurements of plain and sterically stabilised HPC-liposomes (100 nm) in solutions of different ion concentrations. The calculation of the thickness was based on the linear correlation between ln zeta (zeta-potential) and kappa (Debye Hückel-Parameter). FALT was calculated and found to be for plain HPC-liposomes 0.83 +/- 0.17 nm and for PEG-HPC-liposomes 3.57 +/- 0.17 nm. Exchange of the HPC by an alkylphospholipid with different head group has no or only minor effect (PEG-OPP-liposomes 3.44 +/- 0.31 nm). Thus the reduced uptake of HPC-LUVET correlates with an increased thickness of the fixed aqueous layer around these liposomes and could support the hypothesis that the thickness is an important property responsible for preventing opsonization and resulting finally in a reduced macrophage uptake.

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The aim of the study was to investigate for the first time the preparation, physical properties and macrophage activating effect of sterically stabilized liposomes made from hexadecylphosphocholine (HPC, Miltefosine) using different poly(ethylene glycol) lipids for coating. We could demonstrate that it is possible to prepare different liposomal vesicle types (MLV, SUV and LUVET) without any problem and with a high stability in buffer (release of hydrophilic marker was < 5% after half a year) and in plasma (t1/2 up to several days). The preparation method, including size of polycarbon membrane filter used for the preparation of LUVETs had the main influence on vesicle size and size distribution. The addition of a charged lipid like DCP and different amounts of PEG-lipid up to 10% had no effect on size and stability of PEG-LUVETs. A comparison of activating potency of PEG-HPC-vesicles with commonly used HPC-liposomes was performed with mouse peritoneal macrophages. HPC-liposomes induced a clear release of NO and TNF from mouse peritoneal macrophages especially in a synergistical action with LPS. On the contrary the effect of PEG-liposomes was similar to control cells after a combined activation in vivo/in vitro. The reduced interaction of these liposomes with the MPS was also demonstrated by an unchanged carbon ink uptake after treatment of mice (i.p.) with liposomes prepared with and without PEG-lipid. PEG-HPC-liposomes combine the advantages of HPC, liposomes and PEG-coating, resulting in a promising preparation for treatment of mammary cancers.

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Hexadecylphosphocholine (HPC) has been investigated intensively for its cancerostatic properties. One explanation for the mechanism of action of HPC assumes that it plays a role in stimulation of the immune system. In particular, its potency to activate macrophages has already been recognised for different lyso- and ether lipids. Important steps in the cascade for developing cytotoxic effects of macrophages on tumor cells are the release of nitric oxide radicals (NO) and/or tumor necrosis factor (TNF). The aim of our study was to examine the role of HPC as primer and/or trigger for macrophage activation to cytotoxicity. In our experiments we used HPC in free (micellar) or liposomal form in different primer/trigger combinations with lipopolysaccharide (LPS). A weak change in morphology was revealed by electron microscopy, if macrophages were harvested from mice previously treated with HPC or HPC multilamellar vesicles. This observation was quantified by the measurement of NO, TNF and cytotoxic activity of the peritoneal macrophages. A specific release of NO was induced by the combination of in vivo treatment with liposomal HPC and subsequent stimulation by LPS in vitro. This process started only after 12 h of in vitro incubation of macrophages with the endotoxin. The release of TNF was dependent of the primer/trigger combination used. A moderate priming effect was obtained with HPC in liposomal form independently of the trigger. On the other hand, liposomes as priming agents were found to induce a dramatic increase in TNF release after in vitro coculture with the trigger LPS. The high release of NO and TNF is accompanied by only a weak increase in tumor cytostasis. The best results were once more found with macrophages primed with liposomal HPC and then triggered with LPS.

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The human histiocytic cell line U 937, which expresses a number of monocyte markers and properties, was investigated with regard to its ability to be activated for NO and tumor necrosis factor (TNF) release after treatment with alkylphosphocholines (APC) and APC liposomes. Using APC multilamellar vesicles (MLV) a clear dose-dependent increase of NO production could be demonstrated for U 937 cells, whereas the corresponding soluble substances had no effect. The time course of NO release was characterised by a peak between 2 h and 12 h and a strong decrease after 24 h. LPS caused no NO release nor the production of TNF in U 937 cells. The simultaneous incubation of the cells with lipopolysaccharide and APC or APC-MLV, led to a strong increase in TNF production. Closer investigation of the time sequence of this synergistic effect demonstrated that cells, that had first been treated with hexadecylphosphocholine (HPC)-MLV and 4 h later with lipopolysaccharide secreted significantly more TNF into the supernatants than in the experiment where both substances were added simultaneously. From these results it was concluded that APC-MLV are possibly able to act as a primer in the process of lipopolysaccharide mediated TNF induction. Furthermore, a positive influence of phorbol 12-myristate 13-acetate (PMA) on the ability of U 937 cells to produce TNF following a treatment with HPC or HPC-MLV could be observed. PMA-pretreated cells were shown to release much more TNF compared to control cells, which led to the supposition that the immunomodifying activity of APC becomes effective only in more highly differentiated cell types.

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