[Management of cancer patients with oral therapy at home in Brittany and Pays de la Loire areas: Survey (end of 2016) and cartography]

INTRODUCTION

The Cancer Observatory, from the OMEDITs (Observatory for Medicines and Medical Devices and Treatment Innovations) of Bretagne and Pays de la Loire areas has conducted a survey aiming to know and map the current practices of management of patients by Oral Anti-cancer Drug (OAD) in inter-region.

METHODS

Forty eight cancer centers received by e-mail in July and October 2016 a questionnaire concerning the management of OADs : from prescription by the specialist of oncology, to the intervention of the pharmacist (analysis and pharmaceutical consulting), to follow-up by nurse, as well as the financing of this activity and the feelings of the actors about this organizational set up.

RESULTS

Fifty-seven professionals from 31 centers, including the most important ones, responded to the survey. As a result, half of the establishments carry out a pharmaceutical analysis for some or all of the OAD prescriptions and only 30% carry out a pharmaceutical consulting. The nurse consultation is, on the other hand, more largely implanted (74% of the centers) as well as the telephone follow-up (6%). More than 90% of professionals believe that the organizational set up could be improved and more secure by, at least, the stronger involvement of pharmacists, the development of tools for nurse (for monitoring, therapeutic education…) and by improving the city-hospital link.

CONCLUSION

This survey shows the variability in the management of patients under OAD because of the lack of resources to ensure the fairness and sustainability of the organizational set up. The hospital/city link could still be optimized to secure patient care.

Use of Intravenous Polymyxin B During Continuous Venovenous Hemodialysis

Described here is the case of a 23-year-old male with Acinetobacter baumannii sepsis and acute renal failure requiring continuous venovenous hemodialysis treated successfully with intravenous polymyxin B. The drug was administered as a loading dose of 2.5 mg/kg, followed by 2 doses of 1 mg/kg on days 4 and 8, then 0.8 mg/kg daily to complete a 24-day course. A discussion of dosing recommendations for polymyxins in dialysis is presented.

Fatal infection caused by Francisella tularensisin a neutropenic bone marrow transplant recipient

Francisella tularensis is one of the most infectious pathogenic bacteria known. Even though immunity against this organism is thought to be primarily T cell mediated, some evidence suggests that neutrophils may also play an important protective role. We report a case of tularemia in a neutropenic bone marrow transplant recipient that sheds light on the importance of neutrophils in protection against this infection and review clinical aspects of this fascinating infection emphasizing areas of interest for immunocompromised hosts.

Infections caused by Kluyvera species in humans

Kluyvera is a relatively newly described genus in the family Enterobacteriaceae that infrequently causes infections in humans. The organism has been isolated from various clinical specimens, but its significance has not been clearly established. In fact, it has been regarded alternatively as saprophytic, opportunistic, or pathogenic. Since the redefinition of this genus in 1981, case reports of diverse clinical infections occurring under various host conditions have been published. Here we present a critical review of all Kluyvera infections reported in the literature, along with our experience involving 5 additional cases. Most patients received prompt antimicrobial treatment on the basis of susceptibility testing, and overall the clinical outcomes were good. Antimicrobial agents active against most Kluyvera strains include third-generation cephalosporins, fluoroquinolones, and aminoglycosides. In contrast, the resistance to ampicillin, extended-spectrum penicillins, and first- and second-generation cephalosporins is significant. Kluyvera is a potentially virulent pathogen that deserves aggressive treatment designed with an awareness of the organism's antimicrobial resistance patterns.

Haemophilus influenzae osteomyelitis in adults: a report of 4 frontal bone infections and a review of the literature

Haemophilus influenzae occasionally causes hematogenous long-bone osteomyelitis in children. In adults, however, bone infections caused by this organism are extremely rare. We report four adult cases of H. influenzae frontal bone osteomyelitis and review 12 cases from the literature.

The Effects of isoflurane on acetylcholine receptor channels: 3. Effects of conservative polar-to-nonpolar mutations within the channel pore

We performed macroscopic and single-channel current measurements on wild-type (WT) and two mutant muscle-type nicotinic acetylcholine (ACh) receptor channels transiently expressed in HEK-293 cells. The mutants contained polar-to-nonpolar substitutions at the 10' (alpha(2)S10'A beta T10'A gamma delta) and 6' positions (alpha(2)S6'A beta gamma delta S6'A) in the M2 pore region of the channel. We studied the behavior of these channels in the absence and presence of the volatile general anesthetic isoflurane. Both mutations changed the gating behavior of the channel. A comparison of the alpha(2)S10'A beta T10'A gamma delta mutant to WT receptors revealed faster desensitization kinetics, increased sensitivity to ACh, a higher efficacy for activation by the partial nicotinic agonist decamethonium, and a greater number of openings per burst. A comparison of the alpha(2)S6'A beta gamma delta S6'A mutant to WT receptors also revealed increased sensitivity to ACh and an increased burst duration at the single-channel level with ACh as agonist. The alpha(2)S10'A beta T10'A gamma delta mutation increased the sensitivity of the ACh receptor to isoflurane, whereas the alpha(2)S6'A beta gamma delta S6'A mutation did not. These changes were probably not caused by the differential effects of the mutation on channel gating and desensitization. The increased sensitivity of the alpha(2)S10'A beta T10'A gamma delta receptor to isoflurane is state-dependent; the mutation changes the affinity of the closed state but not that of the open state of the channel.

Salmonella enteritidis brain abscess: case report and review

Intracranial infections are unusual manifestations of salmonellosis. Even with adequate medical and surgical interventions these infections are often associated with significant morbidity and mortality. We report a case of brain abscess caused by Salmonella enteritidis associated with a brain neoplasm and review previous reports in the literature.

Anaerobic bacteremia in a neutropenic patient with oral mucositis

An increasing number of anaerobic bloodstream infections in neutropenic cancer patients have been reported in the last decade. The type of anaerobes isolated from most of these patients suggests an oral source of infection. We describe a case of anaerobic bacteremia in a neutropenic patient with oral mucositis that highlights the importance of considering these organisms when selecting empiric prophylactic or therapeutic antimicrobial regimens, especially in the setting of periodontal disease or oral mucositis.

Mechanisms of barbiturate inhibition of acetylcholine receptor channels

We used patch clamp techniques to study the inhibitory effects of pentobarbital and barbital on nicotinic acetylcholine receptor channels from BC3H-1 cells. Single channel recording from outside-out patches reveals that both drugs cause acetylcholine-activated channel events to occur in bursts. The mean duration of gaps within bursts in 2 ms for 0.1 mM pentobarbital and 0.05 ms for 1 mM barbital. In addition, 1 mM barbital reduces the apparent single channel current by 15%. Both barbiturates decrease the duration of openings within a burst but have only a small effect on the burst duration. Macroscopic currents were activated by rapid perfusion of 300 microM acetylcholine to outside-out patches. The concentration dependence of peak current inhibition was fit with a Hill function; for pentobarbital, Ki = 32 microM, n = 1.09; for barbital, Ki = 1900 microM, n = 1.24. Inhibition is voltage independent. The kinetics of inhibition by pentobarbital are at least 30 times faster than inhibition by barbital (3 ms vs. < 0.1 ms at the Ki). Pentobarbital binds > or = 10-fold more tightly to open channels than to closed channels; we could not determine whether the binding of barbital is state dependent. Experiments performed with both barbiturates reveal that they do not compete for a single binding site on the acetylcholine receptor channel protein, but the binding of one barbiturate destabilizes the binding of the other. These results support a kinetic model in which barbiturates bind to both open and closed states of the AChR and block the flow of ions through the channel. An additional, lower-affinity binding site for pentobarbital may explain the effects seen at > 100 microM pentobarbital.

Catch in the primary spines of the sea urchin Eucidaris tribuloides: a brief review and a new interpretation

Previous models of reversible catch in echinoid spines, as a property of muscle or of collagen, are briefly reviewed and discussed. This brief review offers a new interpretation of catch in primary spines of Eucidaris tribuloides, viewing the collagen and small muscles of the catch ligament working together as a variable-length tendon. In the model presented, changes in ligament length when out of catch are accommodated by sliding of discontinuous, interdigitating and cross-link-stabilized columns of collagen fibrils, the muscle layer external to the ligament effecting spine movement. Catch is viewed as a consequence of contraction of small muscles inserted on the collagen columns within the ligament. Ligament shortening tightens the profuse (ca. 30,000/mm2) and highly ordered collagen insertion loops within the stereoms of the spine base and test, and catch results from the multiplicative effect of these friction sites in series. New data are presented on novel structural cross-links between collagen fibrils. The cross-links stabilize the ligament columns. The central ligament in Eucidaris plays a purely passive mechanical role in maintaining the alignment of the spine-test articulation. It contains no muscle and neither contracts nor undergoes catch; its insertions are simple, unlike the complex stereom insertions of the main ligament.

Interactions of general anaesthetics with single acetylcholine receptor channels

We used single-channel recording techniques to study the effects of general anaesthetics on nicotinic acetylcholine receptor channels. Normally, these channels remain open for a few milliseconds. Anaesthetics induce three different patterns of channel activity. Ether causes the channel amplitude to be smaller and noisier than normal; isoflurane induces a flickery pattern in which openings occur in bursts of brief openings; propofol causes the channels to appear as isolated brief openings. These patterns can all be understood in terms of a model in which the anaesthetics bind directly to the channel protein and interrupt the flow of ions through the channel. The difference in pattern is determined by the duration of anaesthetic binding. Ether remains bound for the shortest period (< or = 0.01 ms), followed by isoflurane (0.5 ms) and propofol (> or = 2 ms). The anaesthetics may either be physically obstructing the pore of the channel or acting allosterically by inducing a new, non-conducting conformation of the channel.

Evidence for direct actions of general anesthetics on an ion channel protein. A new look at a unified mechanism of action

BACKGROUND

Ion permeation through the nicotinic acetylcholine receptor channel is inhibited by general anesthetics. This inhibition could be mediated either by binding of anesthetic molecules to the channel protein itself or by the effects of anesthetics on the lipid environment of the protein.

METHODS

Patch clamp recording techniques were used to investigate the effects of ether and propofol on acetylcholine receptor channels in outside-out patches from BC3H-1 cells. The kinetic and conductance properties of single channels were measured. A rapid perfusion system was used to make rapid changes in anesthetic concentration during patch clamp recording to determine the kinetics of inhibition by anesthetics.

RESULTS

Ether, isoflurane (results from previous studies), and propofol produce distinct kinetic patterns of single acetylcholine receptor channel activity. Ether reduces the apparent current amplitude of channels, isoflurane induces flickering channel activity and propofol merely decreases the open time of the channel. The kinetics of inhibition are also different for these anesthetics. Ether (< 40 microseconds) is faster than isoflurane (300-600 microseconds) which is faster than propofol (> or = 2 ms).

CONCLUSIONS

These diverse patterns can be interpreted in terms of a unitary mechanism in which the anesthetics interact directly with the channel protein. Each anesthetic is considered to bind to a site on the protein (perhaps, but not necessarily within the pore of the channel) and interrupt the flow of ions through the pore. Anesthetics have access to this inhibitory binding site even when the gate of the channel is closed. The pattern of channel activity induced by an anesthetic is determined by the frequency and duration of binding events.

Cooperative interactions between general anesthetics and QX-222 within the pore of the acetylcholine receptor ion channel

To test the hypothesis that general anesthetics block nicotinic acetylcholine receptor channels by binding within the pore of the channel, we looked for competitive interactions between ether and QX-222 at the single channel current level. Experiments were performed on outside-out patches excised from BC3H-1 cells. QX-222 causes channels to flicker as it repeatedly binds within the pore of the channel and blocks the flow of current through the channel. Ether reduces the apparent unitary conductance of the channel. This effect of ether may be due to frequent, short-lived, unresolved, blockages of the channel. When both ether and QX-222 are applied, the effects of both drugs are seen on single channels. However, the duration of QX-222 blocking events are longer when ether is present; the duration of block is 0.89 +/- 0.06 ms with 30 microM QX-222 alone and 2.23 +/- 0.37 ms with 30 microM QX-222 + 20 mM ether (n = 5 +/- S.D.; -100 mV). Similar results are obtained when butanol is used in place of ether. We conclude that ether and QX-222 do not compete for a common binding site. Conversely, ether decreases the dissociation rate of QX-222. The simplest interpretation of these data is that the binding sites for ether and the aromatic moiety of QX-222 are distinct but close to each other; when ether is bound to its site, the binding of QX-222 is stabilized. We cannot, however, discount the possibility that ether stabilizes QX-222 by binding to a remote site and allosterically modifying the pore of the channel.

Effects of alcohols and volatile anesthetics on the activation of nicotinic acetylcholine receptor channels

The n-alcohols butanol through nonanol and the volatile anesthetic ether increase the frequency of bursts of nicotinic acetylcholine (ACh) receptor channels induced by low concentrations of agonists. For example, 10 mM butanol increases the burst frequency induced by 0.2 microM ACh (a full agonist) and 1 microM decamethonium (a partial agonist) by 1.6-fold and 2.7-fold, respectively. An increase in burst frequency could arise from effects of the drug on agonist binding, channel gating, or desensitization. To distinguish among these alternatives, we measured the current response to rapid application of saturating concentrations of agonists. We found that 10 mM butanol increases the peak current induced by 100 microM decamethonium by 2-fold. In addition, 20 mM butanol and 3 mM pentanol both decrease the onset time of the current response to 10 mM ACh by about 40%. In contrast, ether does not increase the current response to 100 microM decamethonium and does not significantly change the onset time for 10 mM ACh. Neither ether nor butanol changes the degree of steady state desensitization induced by 0.2 microM ACh. We conclude that butanol and pentanol increase burst frequency by increasing the channel opening rate, whereas ether does so by increasing the agonist binding affinity of the ACh receptor.

[Pharmacokinetics of diphemanil methylsulfate in infants]

BACKGROUND

Diphemanil methylsulfate is an atropin-like drug used in some infants suffering from vagal bradycardia. Its pharmacokinetic parameters are known for adults but not for infants. The report describes these parameters in six infants.

POPULATION AND METHODS

Five infants aged 35 to 109 days (mean: 62 +/- 28) and weighing 3.5 to 5.3 kg (mean: 4.3) were included in the study with the formal consent of their parents. All suffered from vagal hyperreactivity. The sixth younger full-term infant was aged 10 days and weighed 4 kg. They were given a single dose (3 mg/kg) of diphemanil methylsulfate orally, after a minimal fast of 4 hours. Blood samples were collected at T0 and 3, 6, 8, 12 and 24 hours after administration. Urines were also collected from 1 hour before drug administration to 24 hours after. Plasma concentrations of diphemanil methylsulfate were measured by gas-exchange chromatography.

RESULTS

The peak plasma concentration in the five infants occurred at 3.9 +/- 2.3 hours (range: 2.9-8 hours). Half-life was 8.6 +/- 2.4 hours and tended to decrease with age. All the other parameters were identical to those found in adults. The peak plasma concentration occurred in the sixth younger infant at 2.9 hours, with a half-life of 17.2 hours. Renal clearance was high (0.3 l/h/kg).

CONCLUSION

The relatively long half-life of diphemanil methylsulfate allows this drug to be given every 8 hours. This longer interval is more comfortable for the patients and their parents. The high renal clearance suggests that this drug is excreted by both glomerular filtration and tubular secretion.

Contractile properties of the articular capsule or ligament, in the primary spines of the sea-urchin Eucidaris tribuloides

1. The articular capsule or ligament, of the primary spines of the sea-urchin Eucidaris tribuloides behaves as a classical excitable tissue, responding with a shortening or contracture to a variety of stimuli including the cholinergic agonists acetylcholine (ACh), methacholine (MeACh), carbamylcholine (CCh) and nicotine. 2. d-Tubocurarine failed to decrease the amplitude of the acetylcholine-induced contractures, while the contractures elicited by methacholine were blocked by atropine. Neostigmine, but not eserine, increased the amplitude of ACh-induced contractures, suggesting the presence of AChE in the preparation. 3. The cholinergic agonists induced contracture of the ligament, but had quite different kinetics, the rate of rise of the contracture being fastest for ACh and decreasing in the following order: CCh, MeACh and nicotine. 4. Tyramine and octopamine exert an inhibitory action on "catch" and a relaxing effect on the contracting ligament. 5. The time courses of the contractures elicited in the same preparation were virtually identical to those of "catch". Therefore, we propose that "catch" and contracture are only two different aspects of the same phenomenon; namely the contracture of the muscle fibers present in the ligament.

Pharmacokinetics of diphemanil methylsulphate in infants

The pharmacokinetics of diphemanil methylsulphate was evaluated after oral administration of a single 3 mg.kg-1 dose to 5 infants being treated for symptomatic bradycardia. The mean pharmacokinetic parameters of oral diphemanil methylsulphate in infants were similar to those in adults. The mean half-life was 8.6 h. This would allow administration three times a day in infants instead of four to six times a day, as currently prescribed. The mean residence time decreases significantly with age (Spearman's r' = -1), and there is a trend for the half-life to decrease with age (r' = -0.9; NS), suggesting an influence of maturation on its elimination.

Pharmacokinetics of diphemanil methylsulphate in healthy subjects

The pharmacokinetic parameters of oral diphemanil methylsulphate have been evaluated in six healthy male volunteers. Absorption of the drug was slow (tmax = 2 to 4 h), the mean half-life was 8.35 h, and the amount of the drug recovered in urine within 48 h ranged from 0.6 to 7.4% of the administered dose. The results suggest low bioavailability, assuming that the drug is poorly metabolized.

[Pharmacokinetics of 3'-azido-3 deoxy-thymidine (AZT) in a patient undergoing hemodialysis]

Zidovudine (AZT) is the only effective drug in the treatment of AIDS. No data are available on the pharmacokinetics of this drug in patients with end-stage renal disease (ESRD). We report on the pharmacokinetics of zidovudine between sessions of hemodialysis and during the procedure in one patient with ESRD. In 1987 a 40-year-old man with ESRD treated with hemodialysis had the AIDS-related complex. The T4/T8 ratio was 0.49. An enzyme-linked immunosorbent assay and Western Blot studies revealed IgG antibodies specifically directed against HIV. The patient was then treated with zidovudine (100 mg three times daily). Studies of the pharmacokinetics of the drug, conducted between hemodialysis sessions, were performed on days 1 and 14 after the start of zidovudine treatment. Paired arterial and venous blood samples were obtained simultaneously one hour after the start of a hemodialysis session on day 20. The peak and the trough concentrations of zidovudine were 0.61 and 0.15 microgram per milliliter, respectively. We observed a marked accumulation of the main metabolite of zidovudine, G-AZT, with a concentration of about 65 micrograms per milliliter on day 14. The half-life was 2.9 hours. The hemodialysis clearance of zidovudine and its metabolite were 102 and 71 ml per minute, respectively. The half-life of zidovudine was three times longer in our patient than in a normal subject.(ABSTRACT TRUNCATED AT 250 WORDS)

Tetracyclines inhibit tissue collagenases. Effects of ingested low-dose and local delivery systems

In a series of experiments, Golub et al. demonstrated that tetracyclines, but not other antibiotics, can inhibit mammalian collagenases and proposed that this property could be useful in treating diseases, such as periodontal disease (but also included certain medical conditions, e.g., corneal ulcers) characterized by excessive collagen degradation (J Periodont Res 1983, 1984 and 1985; Experientia 1984; Cornea 1984). One effect was the dramatic reduction of tissue collagenase activity within the gingival crevicular fluid (GCF) of periodontal pockets after administering a standard regimen of a tetracycline (e.g., 200 mg minocycline or 1000 mg tetracycline/day). The preliminary studies described below determined the effect of (1) low-dose (LD; 40-80 mg/day) orally administered minocycline on GCF collagenase activity and on the subgingival microflora (Exp. I), and (2) tetracycline-loaded monolithic fibers (TF) on collagenase activity in vitro (Exp. II). In Exp. I, GCF collagenase activity was reduced by 45 to 80% 2 weeks after initiating LD minocycline therapy, an effect that lasted for at least several weeks after stopping drug treatment. No consistent change in the relative proportions of G(+), G(-) and motile subgingival microorganisms was detected as a result of LD treatment suggesting that the reduction in GCF collagenase activity was a direct inhibition of the enzyme by the drug. In Exp. II, 3- and 6-mm lengths of TF in vitro established tetracycline concentrations in 250 microliters of 132 micrograms/ml, from 3-mm lengths, and 265 micrograms/ml, from 6-mm lengths, after an 18-hour incubation.(ABSTRACT TRUNCATED AT 250 WORDS)