Intervention planning for Antibiotic Review Kit (ARK): a digital and behavioural intervention to safely review and reduce antibiotic prescriptions in acute and general medicine.

BACKGROUND: Hospital antimicrobial stewardship strategies, such as 'Start Smart, Then Focus' in the UK, balance the need for prompt, effective antibiotic treatment with the need to limit antibiotic overuse using 'review and revise'. However, only a minority of review decisions are to stop antibiotics. Research suggests that this is due to both behavioural and organizational factors. OBJECTIVES: To develop and optimize the Antibiotic Review Kit (ARK) intervention. ARK is a complex digital, organizational and behavioural intervention that supports implementation of 'review and revise' to help healthcare professionals safely stop unnecessary antibiotics. METHODS: A theory-, evidence- and person-based approach was used to develop and optimize ARK and its implementation. This was done through iterative stakeholder consultation and in-depth qualitative research with doctors, nurses and pharmacists in UK hospitals. Barriers to and facilitators of the intervention and its implementation, and ways to address them, were identified and then used to inform the intervention's development. RESULTS: A key barrier to stopping antibiotics was reportedly a lack of information about the original prescriber's rationale for and their degree of certainty about the need for antibiotics. An integral component of ARK was the development and optimization of a Decision Aid and its implementation to increase transparency around initial prescribing decisions. CONCLUSIONS: The key output of this research is a digital and behavioural intervention targeting important barriers to stopping antibiotics at review (see http://bsac-vle.com/ark-the-antibiotic-review-kit/ and http://antibioticreviewkit.org.uk/). ARK will be evaluated in a feasibility study and, if successful, a stepped-wedge cluster-randomized controlled trial at acute hospitals across the NHS.

Inhibition of long-term potentiation by CuZn superoxide dismutase injection in rat dentate gyrus: involvement of muscarinic M1 receptor.

Long-term potentiation (LTP) and long-term depression represent important processes that modulate synaptic transmission that carries out a key role in neural mechanisms of memory. Many studies give strong evidences on a role of the reactive oxygen species in the induction of LTP in CA1 region of hippocampal slices that was inhibited by adding the scavenger enzyme superoxide dismutase (SOD1). Previous data showed that SOD1 is secreted by many cellular lines, including neuroblastoma SK-N-BE cells through microvesicles by an ATP-dependent mechanism; moreover, it has been shown that SOD1 interacts with human neuroblastoma cell membranes increasing intracellular calcium levels via a phospholipase C-protein kinase C pathway activation. The aim of this study was to investigate the effect of intracerebral injection of SOD1 or the inactive form of enzyme (ApoSOD) on the modulation of synaptic transmission in dentate gyrus of the hippocampus in urethane anesthetized rats. The results of the present research showed that intracerebral injection of SOD1 and ApoSOD in the dentate gyrus of the rat hippocampal formation inhibits LTP induced by high-frequency stimulation of the perforant path. This result cannot be only explained by the dismutation of oxygen radical induced by SOD1 since also ApoSOD, that lacks the enzymatic activity, carries out the same inhibitory effect on LTP induction.

Adaptation and implementation of the ARK (Antibiotic Review Kit) intervention to safely and substantially reduce antibiotic use in hospitals: a feasibility study.

BACKGROUND: Antimicrobial stewardship initiatives in secondary care depend on clinicians undertaking antibiotic prescription reviews but decisions to limit antibiotic treatment at review are complex. AIM: To assess the feasibility and acceptability of implementing ARK (Antibiotic Review Kit), a behaviour change intervention made up of four components (brief online tool, prescribing decision aid, regular data collection and feedback process, and patient leaflet) to support stopping antibiotic treatment when it is safe to do so among hospitalized patients; before definitive evaluation through a stepped-wedge cluster-randomized controlled trial. METHODS: Acceptability of the different intervention elements was assessed for a period of 12 weeks by uptake of the online tool, adoption of the decision aid into prescribing practice, and rates of decisions to stop antibiotics at review (assessed through repeated point-prevalence surveys). Patient perceptions of the information leaflet were assessed through a brief questionnaire. FINDINGS: All elements of the intervention were successfully introduced into practice. A total of 132 staff encompassing a broad range of prescribers and non-prescribers completed the online tool (19.4 per 100 acute beds), including 97% (32/33) of the pre-specified essential clinical staff. Among 588 prescription charts evaluated in seven point-prevalence surveys over the 12-week implementation period, 82% overall (76-90% at each survey) used the decision aid. The median antibiotic stop rate post implementation was 36% (range: 29-40% at each survey) compared with 9% pre implementation (P < 0.001). CONCLUSION: ARK provides a feasible and acceptable mechanism to support stopping antibiotics safely at post-prescription reviews in an acute hospital setting.

p85 regulatory subunit of PI3K mediates cAMP-PKA and estrogens biological effects on growth and survival.

Cyclic adenosine 3'5' monophosphate (cAMP) and protein kinase A (PKA) cooperate with phosphatidylinositol 3' kinase (PI3K) signals in the control of growth and survival. To determine the molecular mechanism(s) involved, we identified and mutagenized a specific serine (residue 83) in p85alpha(PI3K), which is phosphorylated in vivo and in vitro by PKA. Expression of p85alpha(PI3K) mutants (alanine or aspartic substitutions) significantly altered the biological responses of the cells to cAMP. cAMP protection from anoikis was reduced in cells expressing the alanine version p85alpha(PI3K). These cells did not arrest in G1 in the presence of cAMP, whereas cells expressing the aspartic mutant p85D accumulated in G1 even in the absence of cAMP. S phase was still efficiently inhibited by cAMP in cells expressing both mutants. The binding of PI3K to Ras p21 was greatly reduced in cells expressing p85A in the presence or absence of cAMP. Conversely, expression of the aspartic mutant stimulated robustly the binding of PI3K to p21 Ras in the presence of cAMP. Mutation in the Ser 83 inhibited cAMP, but not PDGF stimulation of PI3K. Conversely, the p85D aspartic mutant amplified cAMP stimulation of PI3K activity. Phosphorylation of Ser 83 by cAMP-PKA in p85alpha(PI3K) was also necessary for estrogen signaling as expression of p85A or p85D mutants inhibited or amplified, respectively, the binding of estrogen receptor to p85alpha and AKT phosphorylation induced by estrogens. The data presented indicate that: (1) phosphorylation of Ser 83 in p85alpha(PI3K) is critical for cAMP-PKA induced G1 arrest and survival in mouse 3T3 fibroblasts; (2) this site is necessary for amplification of estrogen signals by cAMP-PKA and related receptors. Finally, these data suggest a general mechanism of PI3K regulation by cAMP, operating in various cell types and under different conditions.

NO-induced neuroprotection in ischemic preconditioning stimulates mitochondrial Mn-SOD activity and expression via Ras/ERK1/2 pathway.

To identify the transductional mechanisms responsible for the neuroprotective effect of nitric oxide (NO) during ischemic preconditioning (IPC), we investigated the effects of this gaseous mediator on mitochondrial Mn-superoxide dismutase (Mn-SOD) expression and activity. In addition, the possible involvement of Ras/extracellular-regulated kinase (ERK) ERK1/2 pathway in preserving cortical neurons exposed to oxygen and glucose deprivation (OGD) followed by reoxygenation was also examined. Ischemic preconditioning was obtained by exposing neurons to a 30-min sublethal OGD (95% N(2) and 5% CO(2)). Then, after a 24-h interval, neurons were exposed to 3 h of OGD followed by 24 h of reoxygenation (OGD/Rx). Our results revealed that IPC reduced cytochrome c (cyt c) release into the cytosol, improved mitochondrial function, and decreased free radical production. Moreover, it induced an increase in nNOS expression and NO production and promoted ERK1/2 activation. These effects were paralleled by an increase in Mn-SOD expression and activity that persisted throughout the following OGD phase. When the neurons were treated with L-NAME, a well known NOS inhibitor, the increase in Mn-SOD expression occurring during IPC was reduced and, as a result, IPC-induced neuroprotection was prevented. Similarly, when ERK1/2 was inhibited by its selective inhibitor PD98059, the increase in Mn-SOD expression observed during IPC was almost completely abolished. As a result, its neuroprotective effect on cellular survival was thwarted. The present findings indicate that during IPC the increase in Mn-SOD expression and activity are paralleled by NO production. This suggests that NO neuroprotective role occurs through the stimulation of Mn-SOD expression and activity. In particular, NO via Ras activation stimulates downstream ERK1/2 cascade. This pathway, in turn, post-transcriptionally activates Mn-SOD expression and activity, thus promoting neuroprotection during preconditioning.

Opposing functions of Ki- and Ha-Ras genes in the regulation of redox signals.

Ras p21 signaling is involved in multiple aspects of growth, differentiation, and stress response [1-2]. There is evidence pointing to superoxides as relays of Ras signaling messages. Chemicals with antioxidant activity suppress Ras-induced DNA synthesis. The inhibition of Ras significantly reduces the production of superoxides by the NADPH-oxidase complex [3]. Kirsten and Harvey are nonallelic Ras cellular genes that share a high degree of structural and functional homology. The sequences of Ki- and Ha-Ras proteins are almost identical. They diverge only in the 20-amino acid hypervariable domain at the COOH termini. To date, their functions remain indistinguishable [4]. We show that Ki- and Ha-Ras genes differently regulate the redox state of the cell. Ha-Ras-expressing cells produce high levels of reactive oxygen species (ROS) by inducing the NADPH-oxidase system. Ki-Ras, on the other hand, stimulates the scavenging of ROS by activating posttranscriptionally the mitochondrial antioxidant enzyme, Mn-superoxide dismutase (Mn-SOD), via an ERK1/2-dependent pathway. Glutamic acid substitution of the four lysine residues in the polybasic stretch at the COOH terminus of Ki-Ras completely abolishes the activation of Mn-SOD, although it does not inhibit ERK1/2-induced transcription. In contrast, an alanine substitution of the cysteine of the CAAX box has very little effect on Mn-SOD activity but eliminates ERK1/2- dependent transcription.

Evidence for secretion of cytosolic CuZn superoxide dismutase by Hep G2 cells and human fibroblasts.

The role so far ascribed to intracellular CuZn superoxide dismutase is that of an intracellular scavenger of oxygen radicals. However, other functions of cytosolic CuZn superoxide dismutase have been hypothesized. For example, CuZn superoxide dismutase incubated with rat hepatocyte cells in culture inhibits 3-hydroxy-3methylglutaryl CoA reductase, thereby reducing cholesterol synthesis. We recently demonstrated the presence of surface membrane receptors for CuZn superoxide dismutase, suggesting possible autocrine or paracrine activities. The aim of the present study was to investigate whether cytosolic CuZn superoxide dismutase can be secreted by human hepatocarcinoma and fibroblast cells lines. Proteins in human hepatocellular carcinoma (Hep G2) cells and human fibroblasts were biosynthetically labelled with [35S]-cysteine; then cell lysates and media were immunoprecipitated with rabbit polyclonal anti-human CuZn superoxide dismutase antibodies and separated by 12% polyacrylamide gel electrophoresis. Both Hep G2 cells and human fibroblasts produce and secrete CuZn superoxide dismutase which was detectable in cells and medium as a single protein band with the same electrophoretic mobility as human erythrocyte CuZn superoxide dismutase. These data suggest that CuZn superoxide dismutase, an enzyme thus far considered to be located exclusively intracellularly is secreted by at least two cell lines. This is consistent with autocrine or paracrine roles for CuZn superoxide dismutase.

Changes in apoprotein distribution between lipoprotein classes of hypercholesterolemic rats treated with ascorbate.

It is known that ascorbate has a lipid lowering effect, accompanied by a drop of apo B, in rats fed a diet enriched with 1.5% of cholesterol (Nath diet). In order to better clarify the role exerted by ascorbate in lipid metabolism, the effect of ascorbate administration on apolipoprotein pattern in rats fed the Nath diet was investigated. Wistar male rats fed for two months the Nath diet were treated i.p. with 60 mg/kg of body weight of ascorbate for 10 days. Blood collection before and after the treatment was performed by intracardiac puncture. Lipoproteins were prepared by preparative ultracentrifugation and their apoprotein content was obtained by densitometric scanning of the apoprotein electhrophoretic pattern. The decrease of total plasma cholesterol and triglycerides and of cholesterol, triglycerides and protein content of all plasma lipoproteins observed in ascorbate treated rats, is accompanied by a marked modification of the apolipoprotein pattern of all lipoprotein classes studied, with an increase of apo E content in VLDL-IDL and LDL fractions (135 and 44% respectively), and a decrease of C (37%), AI (70%) and B (37.5%) apoproteins in VLDL-IDL and of apo C (36%) in LDL. On the contrary, in HDL fraction ascorbate induces an increase of C apoproteins (26%) and a decrease of E and B apoproteins (47% and 71% respectively). The data reported clearly show that in hypercholesterolemic rats the lipid lowering effect of ascorbate administration, is accompanied by a marked modification of the apoprotein pattern of all lipoprotein classes studied.

Presence of CuZn superoxide dismutase in human serum lipoproteins.

It has previously been demonstrated that CuZn-superoxide dismutase (SOD) is secreted by several human cell lines. This suggests that the circulating enzyme derives from both hemolysis and peripheral tissues as a result of cellular secretion. In the present report, we evaluated the presence of CuZn-SOD in human serum lipoproteins by both enzyme-linked immunosorbent assay and Western blot analysis of immunoprecipitated lipoprotein samples. The distribution of CuZn-SOD activity among the different lipoprotein fractions was also determined by the xanthine/xanthine oxidase method. The results demonstrated that CuZn-SOD is noticeably present in serum lipoproteins and mainly in low and high density lipoproteins (LDL and HDL). Moreover, experiments performed by incubating CuZn-SOD with a lipid emulsion and subsequent separation of the lipid fraction by ultracentrifugation showed that this enzyme associates in a saturable manner with lipids. The CuZn-SOD bound to LDL and HDL could exert a physiological protective role against oxidative damage of these lipoprotein classes that carry out a crucial role in the cholesterol transport.

Rab4 affects both recycling and degradative endosomal trafficking.

The small GTPases Rab4, Rab5 and Rab7 are endosomal proteins which play important roles in the regulation of various stages of endosomal trafficking. Rab4 and Rab5 have both been localized to early endosomes and have been shown to control recycling and endosomal fusion, respectively. Rab7, a marker of the late endosomal compartment, is involved in the regulation of the late endocytic pathway. Here, we compare the role of Rab4, Rab5 and Rab7 in early and late endosomal trafficking in HeLa cells monitoring ligand uptake, recycling and degradation. Expression of the Rab4 dominant negative mutant (Rab4AS22N) leads to a significant reduction in both recycling and degradation while, as expected, Rab7 mutants exclusively affect epidermal growth factor (EGF) and low density lipoprotein degradation. As also expected, expression of the dominant negative Rab5 mutant perturbs internalization kinetics and affects both recycling and degradation. Expression of Rab4WT and dominant positive mutant (Rab4AQ67L) changes dramatically the morphology of the transferrin compartment leading to the formation of membrane tubules. These transferrin positive tubules display swellings (varicosities) some of which are positive for early endosomal antigen-1 and contain EGF. We propose that the Rab4GTPase is important for the function of the early sorting endosomal compartment, affecting trafficking along both recycling and degradative pathways.

Dietary and hypothyroid hypercholesterolemia induces hepatic apolipoprotein E expression in the rat: direct role of cholesterol.

Apolipoprotein E (apo E) exerts a protective effect against atherosclerosis, related to its role in intracellular cholesterol removal and remnants clearance. In this study we investigated the effect of dietary and hypothyroid hypercholesterolemia, induced respectively by a high cholesterol diet and by propylthiouracil, on hepatic apo E expression in Wistar male rats. The Northern and Western blot analysis of hepatic mRNA and protein levels showed a 2-3-fold increase of apo E in hypercholesterolemic rats compared to controls. The incubation of FAO rat hepatoma cells with 25-OH cholesterol and mevalonate led to a three-fold increase of apo E mRNA, demonstrating a direct role of cholesterol on apo E expression. This effect was completely abolished by elevating intracellular cAMP levels with forskolin. Immunoblot and immunofluorescence analysis revealed that 25-OH cholesterol/mevalonate strongly increased also apo E protein synthesis and secretion in FAO cells. Our data demonstrate that hypercholesterolemia, apart of the cause (diet or hypothyroidism) induces liver apo E expression in the rat and that this effect can be directly related, via cAMP, to cholesterol.

Free fatty acids modulate LDL receptor activity in BHK-21 cells.

It has been shown that dietary fatty acids affect serum low density lipoprotein (LDL) levels, but the mechanism responsible for this effect is still under debate. Here we investigate the effect of different free fatty acids on LDL receptor activity in BHK-21 cells. These cells possess a classical LDL receptor strongly regulated by substances like 25-OH-cholesterol or lovastatin. Preincubation of cells for 24 h with both oleic (cis 18:1) and its trans counterpart, elaidic acid, enhanced 125I-LDL binding, internalization and degradation, being oleic acid more effective than elaidic acid. Among polyunsaturated fatty acids (PUFA) of the n-6 series arachidonic acid (20:4) enhanced LDL receptor activity more than linoleic acid (18:2), and among PUFA of the n-3 series docosahexaenoic (22:6) and eicosapentaenoic acids (20:5) were more effective compared to alpha-linolenic acid (18:3). Conversely, preincubation of cells with saturated fatty acids, palmitic (16:0) and stearic (18:0) acids, decreased binding, internalization and degradation of 125I-LDL. Scatchard analysis of binding data obtained with palmitic and oleic acids showed that these two fatty acids affect LDL receptor number without altering receptor affinity. The regulatory effect of free fatty acids on LDL receptor activity in BHK-21 cells is consistent with the hypothesis that the ability of fatty acids to modulate LDL-cholesterol levels in vivo is mediated, at least in part, by an action on receptor-dependent uptake of LDL.

NF-kappaB protection against apoptosis induced by HEMA.

The cytotoxicity of dental monomers has been widely investigated, but the underlying mechanisms have not been elucidated. We studied the molecular mechanisms involved in cell death induced by HEMA. In human primary fibroblasts, HEMA induced a dose-dependent apoptosis that was confirmed by the activation of caspases-8, -9, and -3. We found an increase of reactive oxygen species (ROS) and NF-kappaB activation after HEMA exposure. Blocking of ROS production by anti-oxidants had no direct influence on apoptosis caused by HEMA, but inhibition of NF-kappaB increased the fraction of apoptotic cells. Accordingly, mouse embryonic fibroblasts (MEF) from p65-/- mice were more susceptible to HEMA-induced apoptosis than were wild-type controls. Our results indicate that exposure to HEMA triggers apoptosis and that this mechanism is not directly dependent upon redox signaling. Nevertheless, ROS induction by HEMA activates NF-kappaB, which exerts a protective role in counteracting apoptosis.

Secretion and increase of intracellular CuZn superoxide dismutase content in human neuroblastoma SK-N-BE cells subjected to oxidative stress.

CuZn superoxide dismutase (SOD) secretion was detected in media of [35S]cysteine-labeled human neuroblastoma SK-N-BE cells precipitated with antihuman CuZn SOD antibodies. The ability of Fe2+/ascorbate oxidative stress to induce CuZn SOD in SK-N-BE cells was evaluated by Western blot analysis. The results showed that, like human hepatocarcinoma cells and human fibroblasts, SK-N-BE cells secrete CuZn SOD. In addition, the CuZn SOD concentration was higher in cells subjected to oxidative stress than in unstressed cells. The secretion of CuZn SOD and the ability of Fe2+/ascorbate to increase its protein content in SK-N-BE cells indicates that this enzyme protects the brain from damage induced by oxidative stress.

Ascorbate administration to normal and cholesterol-fed rats inhibits in vitro TBARS formation in serum and liver homogenates.

We have recently shown that ascorbate has a hypocholesterolemic and hypotriglyceridemic effect on rats fed a diet enriched with 1.5% cholesterol and 25% hydrogenated coconut oil (Nath diet). In this study we evaluated the effect of intraperitoneal ascorbate administration on susceptibility to lipoperoxidation either in rats fed standard or Nath diet. In normal rats ascorbate treatment decreased (p<0.05) the susceptibility to lipoperoxidation induced by incubation of serum for 24 hours with 2.2 mM Cu++, without altering the normal serum fatty acid profile. In rats fed Nath diet we observed a reduced susceptibility of serum to CU++-induced lipoperoxidation (36%), according with their low levels of serum unsaturated fatty acids (40% less than rats fed standard diet). In these animals ascorbate administration affects serum fatty acid profile leading to a decrease of S/U ratio from 1.6 to 1.2 without significantly modifying the susceptibility of serum to lipoperoxidation. Moreover, the production of spontaneous lipid peroxides in liver homogenates, measured as TBARS levels, was strongly inhibited by ascorbate (p<0.01) in rats fed either standard or Nath diet. These data indicate that ascorbate administration exerts an antioxidant effect and that in hypercholesterolemic rats, in addition to a lipid lowering effect, ascorbate exerts a protective role against the peroxidative damage of lipids.

Circadian rhythms of lipid and apolipoprotein pattern in adult fasted rats.

Data on circadian rhythms of serum lipids and apolipoproteins in animals and in human subjects are scarce. The goal of this study was to investigate the existence of circadian rhythms in the lipids and apolipoproteins of fasted rats. We showed that in fasted rats well-defined circadian rhythms were present in total serum triglycerides and in cholesterol and triglycerides of very low density lipoprotein (VLDL), intermediate density lipoprotein-low density lipoprotein (IDL-LDL) and high density lipoprotein (HDL). Moreover, our data clearly show that the circadian rhythm of lipoproteins is accompanied by a well defined circadian rhythm of B apoprotein, in all lipoprotein classes examined.

Enhanced 3-hydroxy-3-methyl-glutaryl coenzyme A reductase activity in human colorectal cancer not expressing low density lipoprotein receptor.

BACKGROUND: We have previously shown that 63.3% of colorectal cancer neoplastic specimens did not express the Low Density Lipoprotein Receptor (LDLR) protein and that the absence of LDLR predicted shorter survival. We now report the findings of a preliminary study on HMG-CoA reductase (HMG-CoAR) activity in neoplastic tissue specimens of human colorectal cancers (CRC) expressing or not expressing LDLR. MATERIALS AND METHODS: The tissue specimens were obtained from 16 patients (10 males and 6 females) undergoing surgical resection for CRC, and previously characterized for LDLR (7 not expressing LDLR and 9 expressing LDLR). HMG-CoAR activity was measured by radiochemical assay using 14C-HMG-CoA as substrate. RESULTS: HMG-CoAR activity was significantly higher in specimens not expressing LDLR than in those expressing LDLR [8.3 pmol/min/mg prot (2.4-16) vs 3.9 pmol/min/mg prot (1.2-7.8), data expressed as median value and the range, p = 0.02, Wilcoxon Rank sum test)]. CONCLUSIONS: The cholesterol requirement in CRC not expressing LDLR may be met by increasing endogenous synthesis. For this reason, the use of HMG-CoA R inhibitors for the treatment of CRC expressing high HMG-CoAR activity-dependence for growth may be clinically important.

Enhancement of tissue lipoperoxidation in propanil-treated rats.

The i.p. injection of the herbicide propanil to male Sprague-Dawley rats increased the susceptibility to lipoperoxidation of liver and brain rat microsomes. A liver damage produced by propanil treatment was demonstrated by decreased serum levels of cholesterol and triglycerides as compared to serum levels of the lipids in control rats. The cellular damage of rat liver was also confirmed by the increased serum levels of aspartate aminotransferase and alkaline phosphatase activities observed in propanil-treated rats as compared to their activities in control rats.

[Treatment of ischemic heart disease in the elderly. Comparison of diltiazem, verapamil and gallopamil]. / La terapia della cardiopatia ischemica nell'anziano. Confronto diltiazem, verapamil e gallopamil.

The medical therapy of myocardial ischemia in elderly patients has not been well evaluated. We studied the age-related changes in 127 patients with proved coronary artery disease and stable effort angina the efficacy and the safety of diltiazem 120 mg tid, verapamil 120 mg tid and gallopamil 50 mg tid a medium term parallel, double blind cross-over placebo controlled study. All patients have been clinically and ergometrically evaluated. In middle-age patients diltiazem, verapamil and gallopamil induced a significant increasing of exercise duration and time to onset ST segment depression > or = 1 mm. In the elderly patients both verapamil and diltiazem as increased the exercise duration and ischemic threshold, while the diltiazem did not increased the exercise duration even if the time of onset ST segment depression > or = 1 mm is increased. At peak exercise the ST segment depression have been reduced both in middle-age and elderly patients after active drugs. Weekly angina and DNT consumption have been significantly reduced after diltiazem, verapamil and gallopamil in middle-age and elderly patients. Side effects have not been relevant even if gallopamil as a lower frequency of them in comparison to diltiazem and verapamil. No patients stopped the treatment because major side effects. Our experience suggests that diltiazem, verapamil and gallopamil have a similar efficacy and rare well tolerated. The choice of one instead of another must be suggested on the basis of side effects developing.

The effect of L-carnitine on the apolipoprotein pattern of rats fed a cholesterol-rich diet.

1. L-Carnitine was administered to hypercholesterolemic rats for eight days, after which the blood was collected by intracardiac puncture and lipoproteins were collected by preparative ultracentrifuge. 2. The chemical composition of lipoproteins of normal rats and hypercholesterolemic rats before and after L-carnitine treatment was determined. 3. The total serum B and E apoproteins were assayed by rocket electrophoresis, while apoproteins in VLDL, IDL, LDL and HDL were determined by densitometric scanning of SDS and TMU polyacrylamide disc gel electrophoresis. 4. The results obtained showed that the L-carnitine treatment tends to restore to normal values both the chemical composition of lipoproteins and the apoproteins pattern of rats fed on a diet enriched with cholesterol.