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C Martin

Publications and source records attributed to C Martin.

At least 73 records · Page 4Linked to original sources
PubMed2004

[Do we have to monitor foetal heart rate during general anesthesia?].

We present a case of an emergency Caesarean section due to misinterpretation of the cardiotocography (CTG) trace during general anaesthesia for treatment of dental abscess. Following failure of the dental abscess treatment under local anaesthesia, a 29-year-old female in the 36th week of a twin pregnancy was to undergo general anaesthesia. Foetal well-being was monitored with ultrasonographic evaluations of foetal heart rate. During surgery, senior obstetrician recorded a lack of beat-to-beat variability of the cardiotocography trace. The CTG pattern was interpreted as foetal distress and an emergency Caesarean section was performed under general anaesthesia. That was probably due to general anaesthesia. Then, two infants were extracted without neonatal distress necessitating intubation. This case report underlines the risk to misread an intraoperative CTG monitoring and if the CTG monitoring is normal before anaesthesia, reduced foetal beat-to-beat variability with a normal baseline heart rate during general anaesthesia is probably normal.

Adult↗
PubMed2004

Inhibition of P-glycoprotein function by XR9576 in a solid tumour model can restore anticancer drug efficacy.

Resistance to cancer chemotherapy involves both altered drug activity at the designated target and modified intra-tumour pharmacokinetic properties (e.g. uptake, metabolism). The membrane transporter P-glycoprotein (P-gp) plays a major role in pharmacokinetic resistance by preventing sufficient intracellular accumulation of several anticancer agents. Whilst inhibiting P-gp has great potential to restore chemotherapeutic effectiveness in blood-borne cancers, the situation in solid tumours is less clear. Therefore, the degree of resistance tumours pose to the cytotoxicity of vinblastine and doxorubicin was characterised using the multicellular tumour spheroid model. Tumour spheroids were generated from either drug-sensitive MCF7(WT) breast cancer cells or a resistant P-gp-expressing variant (NCI/ADR(Res)). Drug-induced cytotoxicity in tumour spheroids was measured using an outgrowth assay and compared with that observed in monolayer cultures. As anticipated, the 3-D organisation of MCF7(WT) in tumour spheroids was associated with a reduction in the potency of doxorubicin and vinblastine-i.e. the inherent multicellular resistance phenomenon. In contrast, tumour spheroids from NCI/ADR(Res) cells did not display multicellular resistance. However their constitutive expression of P-gp reduced the potency of both anticancer drugs. Moreover, the highly potent P-gp inhibitor, the anthranilic acid derivative, XR9576, was able to restore the cytotoxic efficacy of both drugs in tumour spheroids comprising NCI/ADR(Res) cells. The results suggest that inhibition of P-gp in solid tumours is achievable and that generation of potent inhibitors will provide a significant benefit towards restoration of chemotherapy in solid tissues.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2004

[Therapeutic management of peritonitis].

Antibiotherapy is a fundamental for the treatment of peritonitis. It may be used before surgery or as a complementary treatment after. Experimental models have demonstrated that infections are both aerobic and anaerobic. During the first stage, septicemic with a high death rate, the infection is due to enterobacteria, mostly Escherichia coli. Between D5 and D7 in surviving animals, there is a second stage with abscesses due to anaerobic bacteria, mostly Bacteroides fragilis. The antibiotic treatment must include these two types of bacteria in its spectrum. The role of Enterococcus faecalis is not clearly defined, but this bacterium must be taken into account in case of organ failure or associated septic shock. Treatment options for secondary peritonitis may be, according to severity, cefoxitin, an Augmentin + gentamycin combination, Tazocillin, or ertapenem. The reference treatment for nosocomial or tertiary peritonitis is the imipenem + amikacin combination. An antifungal treatment (fluconazole) is usually necessary, at least until the results of peritoneal fluid culture are available. The duration of treatment is quite variable, ranging from 48 h in less severe forms to 14 days.

Abdominal Abscess↗
PubMed2004

[Heterogeneity of Brain Heart Infusion agar media (BHI): effects on the determination of the vancomycin and the teicoplanin minimal inhibitory concentrations (MIC) of Staphylococcus aureus strains].

The influence of BHI media commercially available on the results of glycopeptides MIC measured by E-test method was studied on 36 S. aureus isolates (21 MRSA and 15 MSSA). The MIC obtained with the vancomycin and the teicoplanin determined by the E-test method, on the ready prepared BHI plates (AES) and the plate prepared at the laboratory among the four dehydrated bases (AES, Biorad, Oxoid, and Becton Dickinson), were compared. The mean of the MIC showed variations from 3.14 (Biorad) to 5.25 mg/L (Oxoid) and from 3.33 (Biorad) to 9.75 mg/L (ready prepared AES) respectively for the vancomycin and for the teicoplanin. A variance analysis (Test de Friedman) showed a significant difference between the five media (p <0.001) with the two antibiotics. The comparison of media 2 by 2 allowed that all combinations excepted one (Biorad vs Becton with the vancomycin) were statistically different (p <0.001). The variation of the MIC observed in relation to the origin of the product of BHI media requires the inclusion of glycopeptide-intermediate S. aureus reference strains to control the prepared culture media.

Anti-Bacterial Agents↗
PubMed2004

An update and guidance on narrowband ultraviolet B phototherapy: a British Photodermatology Group Workshop Report.

Summary These guidelines for use of narrowband (TL-01) ultraviolet B have been prepared for dermatologists by the British Photodermatology Group on behalf of the British Association of Dermatologists. They present evidence-based guidance for treatment of patients with a variety of dermatoses and photodermatoses, with identification of the strength of evidence available at the time of preparation of the guidelines, and a brief overview of background photobiology.

Combined Modality Therapy↗
PubMed2004

Serotyping, stx2 subtyping, and characterization of the locus of enterocyte effacement island of shiga toxin-producing Escherichia coli and E. coli O157:H7 strains isolated from the environment in France.

Twenty-seven Shiga toxin-producing Escherichia coli (STEC) strains were isolated from 207 stx-positive French environmental samples. Ten of these strains were positive for stx(1), and 24 were positive for stx(2) (10 were positive for stx(2vh-a) or stx(2vh-b), 19 were positive for stx(2d), and 15 were positive for stx(2e)). One strain belonged to serotype O157:H7, and the others belonged to serogroups O2, O8, O11, O26, O76, O103, O113, O121, O141, O166, and O174. The environment is a reservoir in which new clones of STEC that are pathogenic for humans can emerge.

Bacterial Typing Techniques↗
PubMed2004

Interferon-tau upregulates prolactin receptor mRNA in the ovine endometrium during the peri-implantation period.

Our objective was to determine the effect of ovine interferon-tau (IFN-tau) on prolactin receptor (PRL-R) gene expression in the ovine endometrium. IFN-tau is an embryonic cytokine which, via its paracrine anti-luteolytic activity, plays a critical role in maternal recognition of pregnancy in ruminants. Using ribonuclease protection assay procedures, we compared endometrial PRL-R mRNA levels in ewes that were intrauterine injected with either 2 mg bovine serum albumin or 2 mg recombinant ovine IFN-tau on day 10 of the oestrous cycle (day 0 = day of oestrus). IFN treatment significantly increased the abundance of both the long and short forms of PRL-R mRNA in the ovine uterus, but had no effect on the long:short form ratio. In situ hybridization experiments revealed that the increase in abundance of PRL-R mRNA in the uterus was localized to the glandular compartment of the endometrium. In pregnant ewes, a similar increase in PRL-R mRNA abundance was found to occur in ovine endometrium on days 14-15 post conception. Collectively, these data provided strong evidence that IFN-tau modulates the level of lactogenic hormone receptor mRNA in the ovine uterus. Whether the effect of IFN-tau on PRL-R expression is mediated directly or influenced, at least in part, by progesterone remains to be elucidated.

Animals↗
PubMed2004

Effect of corn hybrid and chop length of whole-plant corn silage on digestion and intake by dairy cows.

The objectives of this experiment were to study the effects of corn hybrid and chop length of whole-plant corn silage (WPCS) on intake, and to quantify ruminal digestive processes that could help to identify factors limiting dry matter intake (DMI). Eight lactating cows and 4 dry cows fitted with a ruminal cannula were randomly assigned to 4 treatments in a 4 x 4 Latin square design with replications for lactating cows and without for ruminally cannulated cows. Treatments were fed in a total mixed ration (TMR) containing 75% WPCS and 25% concentrate. The 4 WPCS differed in the characteristics of 2 conventional hybrids, less degradable vs. more degradable in the rumen and in the chop length, fine vs. coarse. The DMI was measured for all cows, and digestion measurements and chewing activities were recorded with the cannulated cows. With lactating cows, DMI and milk yield varied with corn hybrids but not with chop length. The less degradable hybrid in the rumen was the less ingested. Dry matter intake of dry ears followed the same trend, but the differences between hybrids were lower than that observed with the lactating cows and not significant. Dry matter digestibility in the total tract and rumen fill were not different between hybrids. Ruminal mean retention time was greater for the least degradable hybrid. The rumen fill capacity could explain intake differences between hybrids. Ingestive mastication strongly reduced particle size, and the efficiency of particle size reduction was more important with the coarsely chopped WPCS than the finely chopped ones. The small differences in particle size of material entering the rumen after mastication of WPCS during eating might explain the lack of response for decreasing chop length. Because the rumen fill decreased with the decrease in chop length, rumen fill could not be the only factor responsible for DMI control of WPCS.

Animals↗
PubMed2004

Cartilage and tympanoplasty.

This study analyzes the morphological and hearing results obtained with cartilage tympanoplasty in retraction pocket, blunting and tympanic membrane lateralization, and cholesteatoma surgeries. Results obtained 3 years postoperatively in 80 patients operated on with cartilage reinforcement of the tympanic membrane (TM) were compared with those obtained 3 years postoperatively in 100 patients operated on with fascia or perichondrium TM reinforcement. Retraction pocket recurrence was found in the patients operated on with fascia or perichondrium in 24% of cases and only in 8% of cases in patients operated on with partial tympanic membrane cartilage reinforcement. No recurrence was found in patients operated on with a total reinforcement of the TM. Cartilage tympanoplasty with skin graft covering the bony external auditory canal (EAC) was performed in 6 cases of severe blunting and/or tympanic membrane lateralization. 3 years post-operatively, good morphological and functional results were obtained in 3 cases. One or two staged ICW procedures were performed in 390 adult patients (416 ears) suffering from a non operated middle ear cholesteatoma. Recurrent and residual cholesteatoma rates were evaluated. Cholesteatomas were operated on with removing the malleus, reinforcing all the tympanic membrane with cartilage and performing an ossiculoplasty with hydroxylapatite prosthesis. The results were compared to those obtained in ICW cholesteatoma surgery with preserving the malleus manubrium, partially reinforcing the eardrum with cartilage and predominantly using an ossicle to perform the ossiculoplasty. Removing the malleus and reinforcing the whole tympanic membrane with cartilage statistically reduced the cholesteatoma recurrence rate for the ICW procedure. This technique, using hydroxylapatite prosthesis for ossiculoplasty gives good hearing results.

Adult↗
PubMed2003

Using a geographical information system to plan a malaria control programme in South Africa.

INTRODUCTION: Sustainable control of malaria in sub-Saharan Africa is jeopardized by dwindling public health resources resulting from competing health priorities that include an overwhelming acquired immunodeficiency syndrome (AIDS) epidemic. In Mpumalanga province, South Africa, rational planning has historically been hampered by a case surveillance system for malaria that only provided estimates of risk at the magisterial district level (a subdivision of a province). METHODS: To better map control programme activities to their geographical location, the malaria notification system was overhauled and a geographical information system implemented. The introduction of a simplified notification form used only for malaria and a carefully monitored notification system provided the good quality data necessary to support an effective geographical information system. RESULTS: The geographical information system displays data on malaria cases at a village or town level and has proved valuable in stratifying malaria risk within those magisterial districts at highest risk, Barberton and Nkomazi. The conspicuous west-to-east gradient, in which the risk rises sharply towards the Mozambican border (relative risk = 4.12, 95% confidence interval = 3.88-4.46 when the malaria risk within 5 km of the border was compared with the remaining areas in these two districts), allowed development of a targeted approach to control. DISCUSSION: The geographical information system for malaria was enormously valuable in enabling malaria risk at town and village level to be shown. Matching malaria control measures to specific strata of endemic malaria has provided the opportunity for more efficient malaria control in Mpumalanga province.

Databases, Factual↗
PubMed2003

Molecular mobility of confined phases in model mesoporous (MCM-41) and microporous (AlPO(4)-5 zeolite) host materials.

The considered host materials are well suited to confine quasi-(1d) molecular phases, seeing that their porosities are composed of parallel unconnected cylindrical pores. For such a simple geometry, confinement effects can be simply described by a single parameter, the pore diameter phi. Our study concerns medium and ultra confinement ranges ( 40 A >or= Ø >or= 7.3 A). The primary effect of such confinements is the decrease of the molecular interactions within the confined phase. As a consequence, we have observed strong triple point depressure Delta T(3t) effects for hydrogen and water confined phases in MCM-41 samples. In the limit case of (1d) phase (the neopentane/AlPO(4)-5 system) it seems that a molecular mobility is observed even at very low temperature T=5 K. The secondary confinement effect is an increase of the interactions between the host inner surface and the confined molecular assembly induced by the pore diameter decreasing. Such host material influence gives rise, for medium range confinement to the physisorption of a curved solid film on the inner surface before the capillary phase condensation (hydrogen/MCM-41 (24 A)) and for ultra confinement to the solidification of the confined phase when the molecular species are commensurate with the inner surface sites (methane/AlPO(4)-5).

Journal Article↗
PubMed2003

The expression of P-glycoprotein does influence the distribution of novel fluorescent compounds in solid tumour models.

Solid tumours display a complex drug resistance phenotype that involves inherent and acquired mechanisms. Multicellular resistance is an inherent feature of solid tumours and is known to present significant barriers to drug permeation in tumours. Given this barrier, do acquired resistance mechanisms such as P-glycoprotein (P-gp) contribute significantly to resistance? To address this question, the multicellular tumour spheroid (MCTS) model was used to examine the influence of P-gp on drug distribution in solid tissue. Tumour spheroids (TS) were generated from either drug-sensitive MCF7(WT) cells or a drug-resistant, P-gp-expressing derivative MCF7(Adr). Confocal microscopy was used to measure time courses and distribution patterns of three fluorescent compounds; calcein-AM, rhodamine123 and BODIPY-taxol. These compounds were chosen because they are all substrates for P-gp-mediated transport, exhibit high fluorescence and are chemically dissimilar. For example, BODIPY-taxol and rhodamine 123 showed high accumulation and distributed extensively throughout the TS(WT), whereas calcein-AM accumulation was restricted to the outermost layers. The presence of P-gp in TS(Adr) resulted in negligible accumulation, regardless of the compound. Moreover, the inhibition of P-gp by nicardipine restored intracellular accumulation and distribution patterns to levels observed in TS(WT). The results demonstrate the effectiveness of P-gp in modulating drug distribution in solid tumour models. However, the penetration of agents throughout the tissue is strongly determined by the physico-chemical properties of the individual compounds.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2003

A cadaveric study of a combined trans-mandibular and trans-zygomatic approach to the infratemporal fossa.

The infratemporal fossa (ITF) is a deep retromaxillary space corresponding to the inferior aspect of the middle cranial fossa. There are numerous surgical approaches, indicating the difficulty of access, accentuated by the communications with the neighboring regions. The aim of this anatomical study was the optimization and photographic demonstration of the pre-auricular infra-temporal trans-zygomatic approach combined with a trans-mandibular approach allowing access to the different regions of the ITF. Six human heads preserved in formalin were dissected under the operating microscope (magnification between x6 and x4). Intra-arterial injection of colored silicone had been done in advance. A plastinated hemi-head was conserved as a teaching and training specimen using the S10 silicone technique. After a pre-auricular temporo-cervical incision, skin flaps, the superficial temporalis fascia and the temporal fascia were elevated. The facial nerve and its branches were preserved and the temporal and zygomatic branches were protected by the superficial temporalis fascia. The division of the temporal muscle and osteotomy of the zygomatic arch opened the superior part of the ITF. Osteotomy of the mandibular ramus preserving the division of the mandibular nerve opened the inferior part of the ITF. This was thus perfectly exposed and access was not impeded by the trunk of the facial nerve and its branches. The place of this complex approach is discussed among the principal exocranial surgical approaches to the ITF.

Cadaver↗
PubMed2003

Effect of age and photoperiodic conditions on metabolism and oxidative stress related markers at different circadian stages in rat liver and kidney.

It has been shown that some cytochrome P450-dependent enzyme activities could present daily fluctuations, particularly CYP3A isoenzymes which are enhanced during the dark period. The aim of this study was to investigate whether age and photoperiodic conditions at different circadian stages could influence these fluctuations. Young mature (10 weeks) and old (22 months) Wistar rats were initially exposed to light-dark cycles 12:12 during 4 weeks, and secondly 18:6 for either one week or six weeks. Erythromycin N-demethylase (CYP3A-dependent), 7-ethoxycoumarin O-deethylase (CYP1A-dependent) and aniline 4-hydroxylase (CYP2E-dependent) activities were determined in liver and kidney microsomes at different hours after darkness onset (HADO). In addition, liver and kidney GSH, GSHPx, ATP, TBARS were determined. During the LD 12:12 cycle, while no significant modification was observed in CYP1A- and 2E-dependent enzyme activities as functions of HADO, erythromycin N-demethylase activity (CYP3A-dependent) showed a significant increase during the second third of the dark period in both young and old rats. After switching to a LD 18:6 cycle, this variation was still observed during second third of the dark period, to a lesser but still significant degree, with no difference between one week and six weeks exposure to the new photoperiod. It can be noted that the old rats showed a significantly lower level of erythromycin N-demethylase activity than the young rats, in parallel to a decrease in GSH, GSHPx and ATP, and an increase in TBARS. These results confirm the lower resistance of old animals to oxidative stress. The observed variations in metabolism parameters underline the need for study designs in pharmaco-toxicology taking into account the possible risks induced by circadian changes, especially in aged subjects.

Aging↗
PubMed2003

[Treatment of phantom pain with botulinum-toxin A. A pilot study].

BACKGROUND: Therapy of phantom pain following amputation is still difficult, since pathophysiological mechanisms are not clarified. Botulinum-toxin A never has been used for this issue. We report four successfully treated cases with chronic phantom pain longer than 3 years. METHODS: We injected 100 IU botulinum-toxin A (4x25 IU in 0,5 ml preservative-free saline 0.9%) in four muscle-triggerpoints of the amputation stump of each patient. All triggerpoints were painful to compression before injection, all patients reported referred sensations in the phantom-foot from at least one of them. Controls were performed by questioning and pain-diaries after 1,2 and 5 weeks. RESULTS: In all cases phantom pain was reduced about 60-80%. The three patients, who had pain attacks, reported a dramatically reduction of the number of attacks (about 90%). In two of them duration of attacks shortened from 120 to 5-10 min and a reduction of pain intensity from VAS 9 to VAS 1 and VAS 9 to VAS 2 was reported. Disorder of sleep disappeared in both affected patients within 2-3 weeks. Three patients,who could move the phantom foot (mental), had a subjective weakness a few days after botulinum-toxin A injection; in one case although injection was performed in the muscles of the femur! CONCLUSIONS: This is the first report of the use of botulinum-toxin A in the treatment of phantom pain. The contribution of the muscles in the cause of phantom pain is unclear and may be local, as a trigger of spinal reflexes or by modulation of "cortical reorganisation" after amputation. Botulinum-toxin A could work analgesic by the relaxation of the stump muscles or by modulation of neuronal transmitters, for example substance P, with an indirect influence of the CNS.

Adult↗
PubMed2003

[Which therapeutic prospects in the septic syndrome?].

OBJECTIVE: To evaluate recent data provided on new treatments of patients with septic shock. DATA EXTRACTION: A Medline search was performed to identify pertinent literature on the pathophysiology of septic shock and treatment strategies from 1990 to 2003. Keywords were "septic shock", "sepsis", "inflammation" and "management". DATA SYNTHESIS: Advances were performed in our current understanding of pathophysiology of sepsis. The loss of homeostatic balance among the systemic inflammatory response and the disturbance of coagulation with generalized coagulopathy lead to organ failures and death. The administration of activated protein C (drotrecogin alfa) reducing this coagulopathy can decrease the mortality of septic shock patients. The modulation of inflammation did not make it possible to improve survival of septic shock patients until now. The efficacy of low doses of steroid has been recently shown in septic shock patients. In addition, new data highlighted the interest of an early goal therapy in patients with sepsis who are admitted to emergency. CONCLUSION: The improvement of survival in septic syndrome patients is a difficult challenge. The uses of different new therapeutic options like protein C reactive, steroids, or early goal therapy in association should make it possible to reduce the mortality in septic patients.

Anti-Infective Agents↗