[Acute pyelonephritis]

The present review details the recommendations for the management of acute pyelonephritis in adults. Acute pyelonephritis corresponds to the infection of the upper urinary tract and is particularly common in women between the age of 15 and 65 years. Symptoms usually include fever, chills, flank pain, nausea and vomiting. There are different types of pyelonephritis, and their management may differ upon the patient's comorbidities and the pathogenic agent. The first step in the management of a patient with suspected acute pyelonephritis focuses on the need for hospitalization. Bacteriological samples should always be collected before the initiation of antibiotics. The antibiotic therapy will then be adapted according to the profile of the infecting pathogen.

Hydroxychloroquine lung pharmacokinetics in critically ill patients with COVID-19

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HCQ pharmacokinetics in COVID-19 patients cannot be predicted using data from lupus or rheumatoid arthritis patients.

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Bronchoalveolar lavage fluid may be a more instructive matrix than plasma on the degree of HCQ lung exposure.

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Low plasma concentrations should not induce an increase in drug dosage because lung exposure could already be high.

Different dosage regimens of hydroxychloroquine (HCQ) have been used to manage COVID-19 (coronavirus disease 2019) patients, with no information on lung exposure in this population. The aim of our study was to evaluate HCQ concentrations in the lung epithelial lining fluid (ELF) in patients infected with SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), the virus that causes COVID-19. This was a retrospective, observational, multicentre, pharmacokinetic study of HCQ in critically ill COVID-19 patients. No additional interventions or additional samples compared with standard care of these patients were conducted in our teaching hospital. We included all intubated COVID-19 patients treated with crushed HCQ tablets, regardless of the dosage administered by nasogastric tube. Blood and bronchoalveolar lavage samples (n = 28) were collected from 22 COVID-19 patients and total HCQ concentrations in ELF were estimated. Median (interquartile range) HCQ plasma concentrations were 0.09 (0.06–0.14) mg/L and 0.07 (0.05–0.08) mg/L for 400 mg × 1/day and 200 mg × 3/day, respectively. Median HCQ ELF concentrations were 3.74 (1.10–7.26) mg/L and 1.81 (1.20–7.25) for 400 mg × 1/day and 200 mg × 3/day, respectively. The median ratio of ELF/plasma concentrations was 40.0 (7.3–162.7) and 21.2 (18.4–109.5) for 400 mg × 1/day and 200 mg × 3/day, respectively. ELF exposure is likely to be underestimated from HCQ concentrations in plasma. In clinical practice, low plasma concentrations should not induce an increase in drug dosage because lung exposure may already be high.

3-month prognostic impact of severe acute renal failure under veno-venous ECMO support: Importance of time of onset

PURPOSE

Veno-venous ECMO is increasingly used for the management of refractory ARDS. In this context, acute kidney injury (AKI) is a major and frequent complication, often associated with poor outcome. We aimed to identify characteristics associated with severe renal failure (Kidney Disease Improving Global Outcome (KDIGO) 3) and its impact on 3-month outcome.

METHODS

Between May 2009 and April 2016, 60 adult patients requiring VV-ECMO in our University Hospital were prospectively included.

RESULTS

AKI occurrence was frequent (75%; n=45), 51% of patients (n=31) developed KDIGO 3 - predominantly prior to ECMO insertion - and renal replacement therapy was required in 43% (n=26) of cases. KDIGO 3 was associated with a lower mechanical ventilation weaning rate (24% vs 68% for patients with no AKI or other stages of AKI; p<0.001) and a higher 90-day mortality rate (72% vs 32%, p=0.002). Multivariate logistic regression suggested that KDIGO 3 occurrence prior to ECMO insertion, as well as PaCO2>57mmHg and mSOFA>12 were independent risks factors for 90-day mortality.

CONCLUSION

KDIGO 3 AKI occurrence is correlated with the severity of patients' clinical condition prior to ECMO insertion and is negatively associated with 90-day survival.

Neurotrophic Effects of Mu Bie Zi (Momordica cochinchinensis) Seed Elucidated by High-Throughput Screening of Natural Products for NGF Mimetic Effects in PC-12 Cells

Post-mitotic central nervous system (CNS) neurons have limited capacity for regeneration, creating a challenge in the development of effective therapeutics for spinal cord injury or neurodegenerative diseases. Furthermore, therapeutic use of human neurotrophic agents such as nerve growth factor (NGF) are limited due to hampered transport across the blood brain barrier (BBB) and a large number of peripheral side effects (e.g. neuro-inflammatory pain/tissue degeneration etc.). Therefore, there is a continued need for discovery of small molecule NGF mimetics that can penetrate the BBB and initiate CNS neuronal outgrowth/regeneration. In the current study, we conduct an exploratory high-through-put (HTP) screening of 1144 predominantly natural/herb products (947 natural herbs/plants/spices, 29 polyphenolics and 168 synthetic drugs) for ability to induce neurite outgrowth in PC12 dopaminergic cells grown on rat tail collagen, over 7 days. The data indicate a remarkably rare event-low hit ratio with only 1/1144 tested substances (<111.25 µg/mL) being capable of inducing neurite outgrowth in a dose dependent manner, identified as; Mu Bie Zi, Momordica cochinchinensis seed extract (MCS). To quantify the neurotrophic effects of MCS, 36 images (n = 6) (average of 340 cells per image), were numerically assessed for neurite length, neurite count/cell and min/max neurite length in microns (µm) using Image J software. The data show neurite elongation from 0.07 ± 0.02 µm (controls) to 5.5 ± 0.62 µm (NGF 0.5 μg/mL) and 3.39 ± 0.45 µm (138 μg/mL) in MCS, where the average maximum length per group extended from 3.58 ± 0.42 µm (controls) to 41.93 ± 3.14 µm (NGF) and 40.20 ± 2.72 µm (MCS). Imaging analysis using immunocytochemistry (ICC) confirmed that NGF and MCS had similar influence on 3-D orientation/expression of 160/200 kD neurofilament, tubulin and F-actin. These latent changes were associated with early rise in phosphorylated extracellular signal-regulated kinase (ERK) p-Erk1 (T202/Y204)/p-Erk2 (T185/Y187) at 60 min with mild changes in pAKT peaking at 5 min, and no indication of pMEK involvement. These findings demonstrate a remarkable infrequency of natural products or polyphenolic constituents to exert neurotrophic effects at low concentrations, and elucidate a unique property of MCS extract to do so. Future research will be required to delineate in depth mechanism of action of MCS, constituents responsible and potential for therapeutic application in CNS degenerative disease or injury.

Estimation of glomerular filtration rate to adjust vancomycin dosage in critically ill patients: superiority of the Chronic Kidney Disease Epidemiology Collaboration equation?

The purpose of this study was to determine the best estimate of glomerular filtration rate (GFR) to adjust vancomycin (VAN) dosage in critically ill patients. Seventy-eight adult intensive care unit patients received a 15 mg/kg loading dose of VAN plus a 30 mg/kg/day continuous infusion. Steady-state concentration was measured 48 hours later and the dose was adjusted to obtain a target concentration ranging from 20 to 25 mg/l. GFR was estimated by measured creatinine clearance (CLCR), Cockcroft, Modification of Diet in Renal Disease and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations. The required dose providing the target concentration was 36±17 mg/kg/day. The first dosage had to be increased in 51% of all patients and in 84% of trauma patients (highest GFR), but had to be decreased in 17% of patients. The closest relationship between clearances of vancomycin was observed with CKD-EPI to GFR. The correlation between clearances of vancomycin and measured CLCR was significant but was rather poor with Cockcroft and Modification of Diet in Renal Disease equation. On the Bland and Altman plots, measured CLCR provided a lower bias but a larger confidence interval and a weaker precision than CKD-EPI. For VAN dose adjustments in intensive care unit patients, Cockcroft formula and Modification of Diet in Renal Disease should be used with caution. In clinical practice, the physician does not have at their disposal the patient's measured CLCR when prescribing. The CKD-EPI appears to be the best predictor of clearances of vancomycin for calculation of a therapeutic VAN regimen.

Endoscopic endonasal skull base surgery

Skull base surgery has been transformed by the development of endoscopic techniques. Endoscopic procedures were first used for pituitary surgery and were then gradually extended to other regions. A wide range of diseases are now accessible to endoscopic skull base surgery. The major advantage of the endoscopic endonasal approach is that it provides direct anatomical access to a large number of intracranial and paranasal sinus lesions, avoiding the sequelae of a skin incision, facial bone flap or craniotomy, and brain retraction, which is inevitable with conventional neurosurgical incisions, resulting in decreased morbidity and mortality and, indirectly, decreased length of hospital stay and management costs. Moreover, the increasing number of publications in this field illustrates the growing interest in these techniques. This paper provides a review of endoscopic skull base surgery. The indications and general principles of endoscopic endonasal skull base surgery are described. Progress in exposure and especially reconstruction techniques is described. This progress now allows more extensive resections, while maintaining acceptable morbidity. The limits of this surgery are also discussed; in particular, although this surgery is often described as "minimally invasive", it is not completely devoid of morbidity.

Large microwave generation from current-driven magnetic vortex oscillators in magnetic tunnel junctions

Spin-polarized current can excite the magnetization of a ferromagnet through the transfer of spin angular momentum to the local spin system. This pure spin-related transport phenomenon leads to alluring possibilities for the achievement of a nanometer scale, complementary metal oxide semiconductor-compatible, tunable microwave generator that operates at low bias for future wireless communication applications. Microwave emission generated by the persistent motion of magnetic vortices induced by a spin-transfer effect seems to be a unique manner to reach appropriate spectral linewidth. However, in metallic systems, in which such vortex oscillations have been observed, the resulting microwave power is much too small. In this study, we present experimental evidence of spin-transfer-induced vortex precession in MgO-based magnetic tunnel junctions, with an emitted power that is at least one order of magnitude stronger and with similar spectral quality. More importantly and in contrast to other spin-transfer excitations, the thorough comparison between experimental results and analytical predictions provides a clear textbook illustration of the mechanism of spin-transfer-induced vortex precession.

Phase-locking of magnetic vortices mediated by antivortices

Synchronized spin-valve oscillators may lead to nanosized microwave generators that do not require discrete elements such as capacitors or inductors. Uniformly magnetized oscillators have been synchronized, but offer low power. Gyrating magnetic vortices offer greater power, but vortex synchronization has yet to be demonstrated. Here we find that vortices can interact with each other through the mediation of antivortices, leading to synchronization when they are closely spaced. The synchronization does not require a magnetic field, making the system attractive for electronic device integration. Also, because each vortex is a topological soliton, this work presents a model experimental system for the study of interacting solitons.

Coupling efficiency for phase locking of a spin transfer nano-oscillator to a microwave current

The phase locking behavior of spin transfer nano-oscillators (STNOs) to an external microwave signal is experimentally studied as a function of the STNO intrinsic parameters. We extract the coupling strength from our data using the derived phase dynamics of a forced STNO. The predicted trends on the coupling strength for phase locking as a function of intrinsic features of the oscillators, i.e., power, linewidth, agility in current, are central to optimize the emitted power in arrays of mutually coupled STNOs.

Administration of hepatitis A vaccine at 6 and 12 months of age concomitantly with hexavalent (DTaP-IPV-PRP approximately T-HBs) combination vaccine

BACKGROUND

Administration of two doses of hepatitis A (HA) vaccine to children > or = 2 years of age has been shown to be protective. The present study assessed whether HA vaccine can be administered as early as 6 months of age and whether it can be administered concomitantly with a hexavalent (HV) vaccine at this age.

METHODS

In an open label, randomized, parallel group study, the liquid HV vaccine (HEXAVAC) (diphtheria, tetanus, 2-component acellular pertussis, inactivated poliomyelitis vaccine, Haemophilus influenzae type b conjugated to tetanus protein and hepatitis B) was administered at 2, 4, 6, and 12 months of age to all children. HA vaccine (VAQTA) was given at 7 and 13 months in the separate administration group (Group 1) and at 6 and 12 months in the concomitant administration group (Group 2). Serum samples were obtained at 2, 7, 12, and 14 months in Group 1 and at 2, 7, 12, and 13 months in Group 2. The primary immunogenicity outcomes were the seroconversion rates for HA 1 month after the second dose of HA vaccine in initially seronegative subjects, and the seroconversion rates for each HV antigen 1 month after the third dose of the HV vaccine (both at 7 months of age).

RESULTS

HA seropositivity rates 1 month after the second dose were 100% in both groups, regardless of initial serostatus. The responses to each HV antigen 1 month after the third dose were similar in both groups. The vaccines were generally well tolerated in both groups regardless of vaccine(s) administered.

CONCLUSIONS

A schedule of two doses of HA vaccine, 6 months apart beginning at 6 months of age is highly immunogenic and well tolerated when administered alone or concomitantly with HV vaccine at 6 and 12 months of age.

Intermittent administration of ceftazidime to burns patients: influence of glomerular filtration

OBJECTIVE

The pharmacokinetics of ceftazidime, the antibiotic of choice for treating acute P. aeruginosa infections, may be modified in burns patients. The aim of this study was to identify the factors causing variations in the serum antibiotic concentrations in bums patients.

METHODS

30 patients with serious burns were randomly divided into two groups. Group 1 received a dose of ceftazidime of 2 x 3 g/24 hours. The second group received the same dose but divided into 6 administrations. Blood samples were taken at 24 (M1) and 48 hours (M2) after the start of treatment and the peak and trough serum concentrations of ceftazidime measured by HPLC. Depending on the results, frequency and/or dose was modified to obtain trough concentrations (Cmin) equal to 16 mg/l, i.e. 4 times the MIC. Either the same dose was maintained, but mostly divided up, or it was increased to 1 g x 8 administrations or it was decreased to 1 g x 4 or 1 g x 3. The serum concentrations of ceftazidime obtained were analyzed taking into account the characteristics of the burns patients (multivariate correlation).

RESULTS

From the first sample (M1) Cmin was lower than the target concentration in 50% of the patients in Group 1 and 20% in Group 2. The modification of the dosing regimen put into place after the first analysis, led to the patients being further divided into four groups before the second blood sampling. Finally, 5 patients ended up in Group 1. In all patients and for all administration times, a negative correlation was found between Cmin and the creatinine clearance, calculated by using Cockcroft's formula.

CONCLUSION

This study highlights the peculiarities of ceftazidime pharmacokinetics seen in burns patients with high interindividual variability. Based on Cmin monitoring and a predefined therapeutic range, dose adjustment was often required. Ceftazidime clearance is correlated with creatinine clearance (Cockcroft's formula), suggesting that this parameter could be used for a priori or a posteriori dose individualization. To respect the summary of the product characteristics (SPC) and reduce the variability in trough concentrations, the dose should be fractionated (1 g x 6) over a 24-hour period or even given as a continuous infusion. Trough concentrations must be evaluated to adapt the dosage regimen to attain target concentrations of 4 x the MIC.

Assessment of renal function in clinical practice at the bedside of burn patients

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

* In burn patients it has been shown ([2]), that there is a correlation between the creatinine clearance (CL(CR)) and the clearance of inulin. * The CL(CR) has never been studied in burn patients who have normal serum creatinine. * The Robert, Kirkpatrick and sMDRD formulae have never been evaluated in burn patients.

WHAT THIS STUDY ADDS

* Despite burn patients having normal serum creatinine concentrations, the study showed that there are large variations in CL(CR) which cannot be detected by single serum creatinine measurements, and which have important implications for drug therapy. * It showed that the formulae currently used to calculate creatinine clearance on the basis of serum creatinine are inadequate for use in burn patients, and they should be abandoned in favour of direct measurement from a 24 h urine collection.

AIMS

The aim of this study was to evaluate whether the renal function of burn patients could be correctly assessed using a single serum creatinine measurement, within normal limits, and three prediction equations of glomerular filtration taking into account, serum creatinine, age, weight and sex.

METHODS

This was a prospective study comprising 36 adult burn patients with a serum creatinine <120 micromol l(-1), within the second or third week following the burn injury. Renal function was assessed using serum creatinine, 24 h urinary CL(CR), and the Cockcroft-Gault, Robert, Kirkpatrick and simplified MDRD equations.

RESULTS

Despite normal serum creatinine concentrations in all patients, a significant number had a decreased CL(CR). The urinary CL(CR) was <80 ml(-1) min(-1) 1.73 m(-2) in nine patients (25%), and <60 ml(-1) min(-1) 1.73 m(-2) in five patients (14%). Between the groups having a CL(CR) lower or greater than 80 ml(-1) min(-1) 1.73 m(-2) there were no differences in gender, burn indices, percentage of mechanically ventilated patients or length of hospital stay, but a difference in age. The highest CL(CR) (>140 ml(-1) min(-1) 1.73 m(-2)) was found in 13 patients younger than 40 years. Regression analysis, residual and Bland-Altman plots revealed that neither the Cockcroft-Gault, Robert, Kirkpatrick nor sMDRD equations were specific enough for the assessment of renal function.

CONCLUSIONS

In burn patients with normal serum creatinine during the hypermetabolic phase, serum creatinine and creatine based predictive equations are imprecise in assessing renal function.

Acute interstitial nephritis after cocaine sniffing

We report the case of a 42-year-old man who developed biopsy-confirmed acute interstitial nephritis (AIN) after cocaine sniffing. He required a few hemodialysis sessions but fully recovered within 3 weeks after cocaine withdrawal and a short course of corticosteroids. AIN should be recognized as a potential cause of acute renal failure in cocaine users, and a history of cocaine use should be carefully elicited in patients with unexplained AIN.

Ghrelin reduces hepatic mitochondrial fatty acid beta oxidation

Ghrelin is a 28-amino-acid peptide secreted during starvation by gastric cells. Ghrelin physiologically induces food intake and seems to alter lipid and glucid metabolism in several tissues such as adipose tissue and liver. Liver has a key position in lipid metabolism as it allows the metabolic orientation of fatty acids between oxidation and esterification. We investigated the effects of peripheral ghrelin administration on 2 crucial parameters of fatty acid oxidation: the levocarnitine (L-carnitine)-dependent entry of the fatty acids in the mitochondria and the mitochondrial fatty acid oxidation. Ghrelin was either given to rats prior to the hepatocyte preparation and culture or used to treat hepatocytes prepared from control animals. Direct incubation of ghrelin to raw hepatocytes did not induce any change in the studied parameters. In hepatocytes prepared from 3 nmol ghrelin-treated rats, a 44% reduction of the mitochondrial fatty acid oxidation while no alteration of the L-carnitine-related parameters were observed. These results suggested (a) that ghrelin has no direct effect on liver, and (b) that when administrated to a whole organism, ghrelin may alter the lipid metabolism and the energy balance through a marked decrease in liver fatty acid oxidation.

Méningite à Escherichia coli multirésistant après biopsie de prostate transrectale

Transrectal prostate biopsy represents the most accurate technique to diagnose prostate cancer. More vigilance is necessary when fluoroquinolones are given as prophylactic agents because of the increase in Escherichia coli resistant strains. We report a case of multiresistant E. coli meningitis after transrectal biopsy resulting in the death of the patient.

Increased amikacin dosage requirements in burn patients receiving a once-daily regimen

Altered pharmacokinetics in burn patients may affect antibiotic plasma concentrations. Typical once-daily dosing (ODD) of 15 mg/kg amikacin (AMK) in burn patients does not always produce peak concentrations (C(max)) reaching the therapeutic objective of six to eight times the minimal inhibitory concentration (MIC). We recorded plasma concentrations following administration of 20 mg/kg AMK in burn patients and studied factors affecting pharmacokinetics. Mean C(max) was 48.3+/-10.8 mg/L and the C(max)/MIC ratio was 6+/-1.35. Statistical analysis demonstrated a relationship between C(max) and the area of the burn and Unit Burn Standard, and between AMK clearance and creatinine clearance (Cl(CR)). We conclude that ODD regimens of AMK in patients with burns >15% body surface area and/or with Cl(CR) >120 mL/min could require doses >20 mg/kg to reach adequate C(max). In all cases, patient therapeutic drug monitoring is essential to ensure the safe usage of these dosing recommendations.

Cefepime in critically ill patients: continuous infusion vs. an intermittent dosing regimen

The aim of this study was to compare the pharmacokinetic and pharmacodynamic parameters of a continuous infusion of cefepime vs. an intermittent regimen in critically ill adult patients with Gram-negative bacilli infection. The prospective randomized parallel study was carried out in 50 patients with severe pneumonia (n = 41) or bacteremia (n = 9). They received cefepime 4 g/d either as a continuous infusion or intermittent administration 2 x 2 g in combination with amikacin. Patient characteristics and the minimal inhibitory concentration (MIC) of the isolated bacteria were comparable. Clinical outcomes were assessed along with pharmacodynamic indices and compared in both groups (chi2 and Mann-Whitney U-tests). Mechanical ventilation, clinical outcome and bacteriological eradication did not significantly differ between the two groups. Also, the area under the plasma cefepime concentration curve at steady state (AUCss: 612 +/- 369 vs. 623 +/- 319 mg x 1(-1) x h), AUCss > MIC (595 +/- 364 vs. 606 +/- 316 mg x 1(-1) x h) and the area under the inhibitory concentration curve (AUICss: 4258 +/- 5819 vs. 5194 +/- 7465 mg x 1(-1) x h) were similar. If the time above MIC (t > MIC) was not significantly higher in Group 1 (100 +/- 0%) than in Group 2 (90 +/- 11%), t > five-fold MIC in Group 1 (100 +/- 0%) was significantly higher (p < 0.01) than in Group 2 (82 +/- 25%). The mean time over the French breakpoint (4 mg/l) was 100 +/- 0% and 72 +/- 27% in Group 1 and 2 (p < 0.001), respectively. In contrast to intermittent cefepime administration, continuous infusion of cefepime consistently maintained a serum concentration > 5 x the MIC of typical Gram-negative nosocomial pathogens. This results in greater bactericidal activity against organisms with a higher (2 mg/l) cefepime breakpoint even if the clinical outcome is not significantly modified.

Severe hypophosphatemia in a patient with anorexia nervosa during enteral refeeding

Hypophosphatemia is a seldom but potentially fatal complication of the nutritional recovery or refeeding syndrome in patients with protein-calorie malnutrition or starvation. We report here the case of a 35-year-old anorexic patient who presented a severe but uncomplicated hypophosphatemia during enteral refeeding, despite phosphorus supplementation. Serum phosphorus monitoring is recommended in severely malnourished anorexic patients, particularly during the first week of refeeding, be it parenteral or enteral.

[Current debate on hormone replacement therapy]

The American Women's Health Initiative Study was stopped 2 years ago. Last year the British One Million Women Study was published. Both studies led to a critical discussion of hormone replacement therapy. Since then media, scientists and physicians have been discussing pros and cons. There is no agreement so far, but the German Senology Society and the German Society for Gynecology and Obstetrics declared their positions on this issue. The discussion focuses on the association between hormone replacement therapy and breast cancer. In vitro studies showed that estrogens stimulate the epithelium of the breast. Prolonged exposure to estrogens (e.g. early menarche and late onset of menopause) can promote breast cancer. Indications for hormone therapy are climacteric symptoms, prophylaxis of osteoporosis, improvement of cognitive functions as well as prophylaxis of dementia. These indications are discussed in the light of recent studies.

Novel promiscuous HLA-DQ HIV Nef peptide that induces IFN-gamma-producing memory CD4+ T cells

We describe the highly conserved sequence 56-68 of the HIV Nef protein as the first promiscuous HLA-DQ HIV-derived peptide. The Nef peptide exhibits an albeit rare capacity to bind 6 different HLA-DQ molecules whereas no binding is observed with the 10 HLA-DR molecules tested. In agreement with these data, after immunization with the Nef peptide, HLA-DQ transgenic Abeta degrees mice display a vigorous cellular and humoral response while the specific immune response of HLA-DR expressing mice is minimal. The promiscuous potentiality of the Nef 56-68 peptide in humans has been confirmed by ex vivo immunization experiments with CD4+ T cells from 14 healthy donors expressing different HLA genotypes. Nef 56-68 specific CD4+ T cells rapidly acquire a memory cell phenotype and are characterized by the preferential usage of the TCR Vbeta 6.1 gene segment and predominant production of IFN-gamma. Taken together, these data indicate that the Nef 56-68 peptide constitutes an attractive component of vaccines aiming at inducing or enhancing HIV-specific T cell immunity.

[Pediatric rhabdomyosarcoma of the infratemporal fossa]

OBJECTIVE

Prognosis of rhabdomyosarcoma of the infratemporal fossa is generally poor. We report our experience.

MATERIAL AND METHODS

Twenty-three children with rhabdomyosarcoma of the infratemporal fossa were treated at the Gustave Roussy and Curie Institutes between 1984 and 1999. Seventeen children received radiotherapy (group 1), four children were treated surgically with or without postoperative radiotherapy (group 2), and two children received no further treatment after chemotherapy (group 3).

RESULTS

In group 1, there were 10 local recurrences and one metastatic failure; all 11 children died from their disease. Nodal recurrence was salvaged successfully in one other with chemotherapy and surgery. In group 2, three children were disease free at 3 years and one died of local recurrence. In group 3, one child experienced a local recurrence successfully salvaged with radiotherapy. This child was disease free at 3 years. The other child developed local recurrence and died.

DISCUSSION

Overall survival rate in our patients was 50%. Local control remained the main prognostic factor for survival. Surgery has already been shown to improve local control in other localizations of rhabdomyosarcoma. If residual tumor tissue remains after neo-adjuvant chemotherapy, surgery should be considered in a multidisciplinary discussion of therapeutic options. Indications for postoperative radiotherapy depend on age and histological features of the surgical specimen.

[Importance of a cefpirome-vancomycin combination on bactericidal kinetics in severe MRSA infections in intensive care]

Vancomycin is always the drug of choice for treatment of infections caused by methicillin-resistant Staphylococcus aureus (MRSA) in spite of his bactericidal kinetic.

BACKGROUND

The aim of this study was to evaluate in vivo the improvement of bactericidal kinetic of vancomycin associated with cefpirome against MRSA infection in critically ill patients.

METHODS

The prospective cross-over study was carried out in 20 patients with severe pneumonia or bacteremia. There were randomized to receive vancomycin 2 g per day (Group 1, n = 10) or vancomycin with cefpirome 2 g x 2 (Group 2, n = 10). Clinical recovery, bacteriologic parameters (bactericidal kinetic and bactericidal power in vivo at the peak and the valley), duration of ventilation and stay in ICU were comparatively explored in both groups.

RESULTS

Clinical outcome did not significantly differ between Group 1 and 2. Bactericidal kinetics were better in the Group 2 (40% vs 60% after 6 hours to the dilution for 1/8e) but the difference was not significant. However, bactericidal power in sera was also better in the Group 2 with more bactericidal dilution at 1/16e (68% vs 88.8%: NS) and overall at 1/32e (10.5% vs 50%: p < 0.05) and CRP, an inflammatory marker, was significantly lower in the Group 2 than in the Group 1 (119.5 +/- 24 mg/l vs 198.6 +/- 78 mg/l: p < 0.05) on the third day.

Thyroid hormone controls carnitine status through modifications of gamma-butyrobetaine hydroxylase activity and gene expression

The carnitine system plays a key role in beta-oxidation of long-chain fatty acids by permitting their transport into the mitochondrial matrix. The effects of hypothyroidism and hyperthyroidism were studied on gamma-butyrobetaine hydroxylase (BBH), the enzyme responsible for carnitine biosynthesis in the rat. In rat liver, BBH activity was decreased in the hypothyroid state and increased in hyperthyroid animals. The modifications in BBH activity correlated with changes in the enzyme Vmax values. These changes were shown to be related to hepatic BBH mRNA abundance. Thyroid hormones are known to interact with lipid metabolism, in particular by increasing long-chain fatty acid oxidation through activation of carnitine-dependent fatty acid import into mitochondria. Our study showed that thyroid hormones also increased carnitine bioavailability.

Influence of the physiological changes of gastric emptying on the simplified single sample 14 C-urea breath test

The aim of this study was to assess the influence of the physiological changes of gastric emptying on the simplified 14C-urea breath test. Thirty patients performed the test in fasting conditions. Patients were orally administered 0.074 mega Bq of 14C-urea, mixed with 0.0185 mega Bq of 99mTc-S colloids in 25 ml water. A breath sample was taken before and 10 min after intake of the tracers and followed by a 2 min planar anterior scintigraphic image of the abdomen to measure gastric activity. Gastric emptying was estimated by dividing the residual gastric activity at 10 min by the total activity in the abdomen. The procedure was performed twice for each patient after a 24 h interval. The repeatability of both the gastric emptying test and the urea breath test was assessed by the method described by Bland and Altman. The coefficient of repeatability of the urea breath test was 1.18 for a confidence interval of 95%. The coefficient of repeatability of gastric emptying was 27.4. There was no significant correlation (r= 0.08) between the plot of the individual modifications of urea breath test and residual gastric activity in two successive tests. It is concluded that the physiological changes of gastric emptying do not influence the results obtained by the simplified, single-sample 14C-urea breath test.

Autosomal-dominant periodic fever with AA amyloidosis: Novel mutation in tumor necrosis factor receptor 1 gene Rapid Communication

BACKGROUND

The recent identification of genes responsible for syndromes of periodic fever with amyloidosis has opened the way to a molecular diagnosis of hereditary AA amyloidosis.

METHODS

A Belgian woman presented for genetic counseling. Three first-degree relatives had a diagnosis of renal amyloidosis with a history of recurrent fever and inflammatory episodes. Medical records and pathological specimens were obtained from all physicians who had been in charge of her three relatives. Immunohistochemical staining was performed on paraffin-embedded material. A mutation search was performed in the MEFV (Mediterranean fever) and tumor necrosis factor receptor 1 (TNFR1 or TNFRSF1A) genes causing familial Mediterranean fever (FMF) and tumor necrosis factor receptor-associated periodic syndrome (TRAPS), respectively.

RESULTS

The family history was consistent with autosomal-dominant transmission of periodic fever with arthralgias, abdominal pain, and eventual AA amyloidosis involving the kidneys, digestive tract, and thyroid. Recurrent amyloidosis in kidney graft was demonstrated in one patient and was suspected in the other. A novel heterozygous mutation (C55S) in TNFRSF1A was identified in the affected patient available for genetic testing but not in the asymptomatic woman requiring counseling. No mutation was detected in MEFV.

CONCLUSIONS

We report a novel mutation (C55S) in TNFRSF1A, resulting in autosomal-dominant periodic fever and AA amyloidosis. This condition, known as TRAPS, should be added to the differential diagnosis of hereditary renal amyloidosis, with obvious implications for management and genetic counseling.

Synthesis of [18F]-labeled EF3 [2-(2-nitroimidazol-1-yl)-N-(3,3,3-trifluoropropyl)-acetamide], a marker for PET detection of hypoxia

[18F]-2-(2-Nitroimidazol-1-yl)-N-(3,3,3-trifluoropropyl)-acetamide ([18F]-EF3) has been prepared, in 65% chemical yield and 5% radiochemical yield, by coupling 2,3,5,6-tetrafluorophenyl 2-(2-nitroimidazol-1-yl) acetate 1 with [18F]-3,3,3-trifluoropropylamine 7. This original radiolabelled key-synthon was obtained in 40% overall chemical yield by oxidative [18F]-fluorodesulfurization of ethyl N-phthalimido-3-aminopropane dithioate 4, followed by deprotection with hydrazine of the resulting [18F]-N-phthalimido-3,3,3-trifluoropropylamine 5. All the process was performed within 90 min, from the [18F]-HF production in the cyclotron to the purification of the final target.

Importance of precise timing in the simplified 10-min 14C-urea breath test procedure

This study was performed to assess the impact of precise timing and the repeatability of the simplified 10-min 14C-urea breath test. Thirty-three patients underwent a 14C-urea breath test at 10 and 12 min (test I) and after 24 h (test II). The paired t-test was applied to assess differences between two successive measurements at 10 and 12 min, and the method of Bland and Altman was used to evaluate the repeatability of the test. Only test I (P = 0.004) showed a significant difference between two successive measurements at 10 and 12 min. The coefficients of repeatability at 10 and 12 min were 1.54 and 1.48, respectively. No bias was found. From this study, we can conclude that breath collections, delayed by 2 min (20% error), have no impact on the clinical interpretation of the results. The repeatability of the simplified 10-min 14C-urea breath test is sufficient for clinical use.

Characterization of a Na+-Ca2+ exchanger NCX1 isoform in bovine fasciculata cells of adrenal gland

The Na+-Ca2+ exchanger (NCX) is well known to regulate intracellular Ca2+ concentration in many excitable cells. To date, three members of the NCX exchanger gene family have been identified: NCX1, NCX2 and NCX3. In zona fasciculata of the bovine adrenal gland, a Na+-Ca2+ exchanger has been recently found to display biochemical similarities with the NCX1 exchanger of renal basolateral cells. Although a Na+-Ca2+ exchanger has already been characterized in zona medulla of adrenal gland, such an exchanger has never been studied in the adrenal cortex. Thus, we have used a reverse transcriptase-polymerase chain reaction (RT-PCR) assay with specific NCX primers on fasciculata cell cultures. The sequencing of the amplified fragment revealed, for the first time, the presence of a NACA3 isoform of the NCX1 exchanger in the adrenal cortex, similar to the one found in adrenal chromaffin cells and in renal cortex. This isoform is 92 and 94% identical in the portion compared with kidney Na+-Ca2+ exchanger NACA3 of rat and pig, respectively.

Late-onset renal failure in Senior-Loken syndrome

We report on four patients, from three different families, with Senior-Loken syndrome (SLS). They were unusual in that they reached end-stage renal failure (ESRF) only during the fifth or sixth decade. SLS is an autosomal-recessive disorder defined by the association of nephronophthisis and retinal dystrophy. Affected individuals invariably progress to ESRF, usually before the age of 20 years. The diagnosis was based on typical clinical presentation and characteristic renal histology, that is, a picture of chronic interstitial nephritis with pronounced thickening and multilayering of tubular basement membranes. Deterioration of renal function was slow, leading to ESRF between the ages of 42 and 56 years. Retinal dystrophy, already symptomatic during childhood in two patients, led to severe visual impairment in all. In contrast with four cases of SLS recently reported in very young patients, the NPH1 gene (the main gene responsible for nephronophthisis) was not deleted in our two tested patients. We conclude that SLS should be considered in adults who suffer from both chronic interstitial nephropathy and retinal degeneration. Whether the SLS is a variant of nephronophthisis and whether early- and late-onset renal failure in SLS is accounted for by genetic or allelic heterogeneity remain to be determined.

[Management of acute respiratory distress syndrome in Midi-Pyrnees]

OBJECTIVE

To assess management of acute respiratory distress syndrome (ARDS) in Midi-Pyrénées, France.

METHODS

A prospective study using a questionnaire divided into 10 parts, definition, etiology, radiography, computed tomography, management, was conducted in 26 intensive care units in the Midi-Pyrénées. Management of ARDS in Midi-Pyrénées was comparted with management elsewhere as described in the literature.

RESULTS

Overall participation rate was 73%. Disparities were found concerning the definition. Four etiologies accounted for 75% of all ARDS cases. Chest x-rays were used for positive diagnosis and thoracic scans for complications. Ventilatory and hemodynamic optimizations were the first line therapy used. Twenty-nine percent and 41% of the intensive care unites used nitric oxide and prone position respectively.

CONCLUSIONS

There are differences between ARDS management in Midi-Pyrénées and that described in the current literature. Epidemiologic studies such as this one are necessary before publishing guidelines for the management of ARDS.

Cold acclimation or grapeseed oil feeding affects phospholipid composition and mitochondrial function in duckling skeletal muscle

The phospholipid fatty acid (FA) composition and functional properties of skeletal muscle and liver mitochondria were examined in cold-acclimated (CA, 4 degrees C) ducklings. Phospholipid FA of isolated muscle mitochondria from CA birds were longer and more unsaturated than those from thermoneutral (TN, 25 degrees C) reared ducklings. The rise in long-chain and polyunsaturated FA (PUFA, mainly 20:4n-6) was associated with a higher State 4 respiration rate and a lower respiratory control ratio (RCR). Hepatic mitochondria, by contrast, were much less affected by cold acclimation. The cold-induced changes in phospholipid FA profile and functional properties of muscle mitochondria were reproduced by giving TN ducklings a diet enriched in grapeseed oil (GO, rich in n-6 FA), suggesting a causal relationship between the membrane structure and mitochondrial functional parameters. However, hepatic mitochondria from ducklings fed the GO diet also showed an enrichment in long-chain PUFA but opposite changes in their biochemical characteristics (lower State 4, higher RCR). It is suggested that the differential modulation of mitochondrial functional properties by membrane lipid composition between skeletal muscle and liver may depend on muscle-specific factors possibly interacting with long-chain PUFA and affecting the proton leakiness of mitochondrial membranes.

Evaluation of the 13C-aminopyrine breath test using nondispersive infrared spectrometry

OBJECTIVE

The aim of the study was to assess the value of the 13C Aminopyrine Breath Test (ABT) when performed using the NonDispersive InfraRed Spectrometry (NDIRS), which is a simple and cheap alternative to the mass spectrometry.

METHODS

The results obtained by using the NDIRS method for performing the ABT were compared to the results obtained by a reference method, the 14C Aminopyrine Breath Test. For this purpose, in 32 patients admitted for various liver problems, an ABT was performed by using the 2 methods simultaneously. The repeatability of the results obtained at 120 minutes by the NIDRS method as compared to the 14C test was assessed by the method of Bland and Altman.

RESULTS

The mean of difference between the results obtained by both methods at 120 minutes was 0.06 +/- 0.46. The coefficient of repeatability between the two tests was 0.92 for a confidence interval of 95%. A good correlation (r = 0.93) was found between all individual results obtained in breath samples at different times of collection (30, 60, 90, 120 minutes), and between the results obtained at 120 minutes for both 13C and 14C tests (r = 0.94).

CONCLUSION

The 13C ABT performed using NDIRS is a valid alternative to the 14C technique in routine clinical practice.

Structural diversity of human class II histocompatibility molecules induced by peptide ligands

SDS-PAGE analyses of stable HLA-DR1 complexes indicate that the binding of T cell epitopes can lead to multiple conformational variants. Whereas short T epitopes (<14-mer) induce complexes with apparent MW ranging from 47 to 57 kDa, longer peptides form generally high mobility complexes (44-45 kDa). The generation of HLA-DR1 conformational variants appears dependent on core peptide residues fitting inside the groove but can additionally be attributed to the presence of N- and C-terminal flanking residues (PFRs) acting as a complementary mechanism. These PFRs can jointly affect major histocompatibility complex class II conformation and stability, supporting the existence of alternative contacts at a distance from the classical binding site.