The impact of comorbidities and their stacking on short- and long-term prognosis of patients over 50 with community-acquired pneumonia.

BACKGROUND: The prognosis of patients hospitalized with community-acquired pneumonia (CAP) with regards to intensive care unit (ICU) admission, short- and long-term mortality is correlated with patient's comorbidities. For patients hospitalized for CAP, including P-CAP, we assessed the prognostic impact of comorbidities known as at-risk (AR) or high-risk (HR) of pneumococcal CAP (P-CAP), and of the number of combined comorbidities. METHODS: Data on hospitalizations for CAP among the French 50+ population were extracted from the 2014 French Information Systems Medicalization Program (PMSI), an exhaustive national hospital discharge database maintained by the French Technical Agency of Information on Hospitalization (ATIH). Their admission diagnosis, comorbidities (nature, risk type and number), other characteristics, and their subsequent hospital stays within the year following their hospitalization for CAP were analyzed. Logistic regression models were used to assess the associations between ICU transfer, short- and 1-year in-hospital mortality and all covariates. RESULTS: From 182,858 patients, 149,555 patients aged ≥ 50 years (nonagenarians 17.8%) were hospitalized for CAP in 2014, including 8270 with P-CAP. Overall, 33.8% and 90.5% had ≥ 1 HR and ≥ 1 AR comorbidity, respectively. Cardiac diseases were the most frequent AR comorbidity (all CAP: 77.4%). Transfer in ICU occurred for 5.4% of CAP patients and 19.4% for P-CAP. Short-term and 1-year in-hospital mortality rates were 10.9% and 23% of CAP patients, respectively, significantly lower for P-CAP patients: 9.2% and 19.8% (HR 0.88 [95% CI 0.84-0.93], p < .0001). Both terms of mortality increased mostly with age, and with the number of comorbidities and combination of AR and HR comorbidities, in addition of specific comorbidities. CONCLUSIONS: Not only specific comorbidities, but also the number of combined comorbidities and the combination of AR and HR comorbidities may impact the outcome of hospitalized CAP and P-CAP patients.

Reasons for intravesical instillation postponement during adjuvant treatment of non-muscle-invasive bladder cancer: A prospective study.

INTRODUCTION: Intravesical instillations for adjuvant treatment of non-muscle-invasive bladder cancer (NMIBC) may be postponed of necessity. However, the frequency and reasons for postponement are unclear. MATERIALS: We carried out a prospective, epidemiological study in an Urology department of the Île-de-France, between August 2016 and March 2017, to determine the frequency and reasons for postponement of intravesical instillations during adjuvant treatment of NMIBC. One-hundred consecutive patients treated by intravesical instillations of mitomycin C (MMC) or Bacillus Calmette-Guérin (BCG) were included. At each session and in case of instillation postponement, the medical team completed a specially designed questionnaire. RESULTS: A total of 541 instillations were performed in the 100 patients. Twenty-four instillations (4.4%) were postponed in 19 patients. The major cause of postponement was an untreated positive urine analysis and culture (UAC) in 13/24 (54%) cases. The causes of cancellation did not differ significantly between MMC and BCG. The most frequently cancelled instillations were the first in the therapeutic protocol in 26% of cases. The number of instillations preceding those cancelled did not differ significantly between MMC and BCG (2.1±2.0 instillations for MMC vs. 1.5±1.6 for BCG; P=0.64). CONCLUSIONS: There was a low rate of postponed instillations (4.4%). The main reasons, namely an untreated UAC and a positive dipstick test, based on the jurisprudence, are not included in the latest CC-AFU guidelines. LEVEL OF EVIDENCE: 3.

Relevance of TSH evaluation in elderly in-patients with non-thyroidal illness.

BACKGROUND: Non-thyroidal illness (NTI) is frequent in hospitalized patients. Its recovery is characterized by a raise in TSH levels. However, the clinical significance of high TSH levels at admission in hospitalized elderly patients with NTI remains uncertain. AIM: To explore the relevance of baseline TSH evaluation in hospitalized elderly patients with NTI. METHODS: We examined the participants with NTI (n = 123) from our previous study (Sforza, 2017). NTI was defined as: low T3 (< 80 ng/dL) and normal or low total T4 in the presence of TSH values between 0.1 and 6.0 mU/L. Thyroid function tests were performed on day 1 and day 8 of the hospital stay. Positive TSH changes (+ ΔTSH) were considered when the day-8 TSH value increased more than the reference change value for TSH (+ 78%). Multiple logistic regression was used to evaluate the independent association of baseline TSH, sex, clinical comorbidities (by ACE-27) and medications with + ΔTSH. RESULTS: Out of 123 patients (77 ± 8 years, 52% female), 34 showed a + ΔTSH. These patients had a lower TSH at admission (p < 0.001) and intra-hospital mortality (p = 0.003) than the others. In multiple logistic regression, TSH > 2.11 mU/L at baseline was associated with reduced odds to show + ΔTSH [odds ratio (95 CI) 0.29 (0.11-0.75); p = 0.011] in a model adjusted by age, sex and ACE-27. DISCUSSION: Inappropriately higher TSH levels at admission in hospitalized elderly patients were associated with a reduced ability to raise their TSH levels later on. The present results confront the idea that TSH levels at admission are irrelevant in this clinical context.

Hypothyroidism in hospitalized elderly patients: a sign of worse prognosis.

PURPOSE: Overt hypothyroidism has adverse clinical consequences and might worsen prognosis in critically ill elderly patients. However, the difficult interpretation of thyroid function tests (TFT) due to non-thyroidal illness (NTI) has led to discouragement of screening for thyroid dysfunction. Our aim was to determine the prevalence of TFT compatible with hypothyroidism and to study its influence on mortality among hospitalized elderly patients. METHODS: In this prospective study we consecutively included all patients ≥60 years admitted by the Internal Medicine Department to the hospital ward (n = 451) of the Cesar Milstein Hospital in Buenos Aires, Argentina. TFT were done on day 1 and 8. Thyroid function categories were defined as overt and subclinical hypothyroidism, overt and subclinical hyperthyroidism, euthyroidism and NTI. Stage of chronic kidney disease (CKD), Adult Comorbidity Evaluation (ACE)-27, and intra-hospital mortality were recorded. The association between mortality and TFT categories was studied by Cox regression. RESULTS: Out of 451 patients (77.0 ± 7.9 years, 54% females) 76% were categorized as NTI, 4% as overt hypothyroid, 10% as subclinical hypothyroid, 1% as subclinical hyperthyroid and 9% as euthyroid. Overt hypothyroid patients showed significantly higher mortality than the rest of the groups (25%, p < 0.05) while ACE-27 was similar among all of them (p = 0.658). In addition, patients within the overt hypothyroid category showed a higher mortality rate than NTI in a model adjusted by Stage 5-CKD, ACE-27, sex and age [HR 3.1 (1.14-8.41), p < 0.026]. CONCLUSION: Overt hypothyroidism during hospitalization was associated with elevated mortality. Further studies would reveal if TFT alterations compatible with hypothyroidism should be diagnosed/treated in hospitalized elderly patients.

The translation of recombinant proteins in E. coli can be improved by in silico generating and screening random libraries of a -70/+96 mRNA region with respect to the translation initiation codon.

Recombinant protein translation in Escherichia coli may be limited by stable (i.e. low free energy) secondary structures in the mRNA translation initiation region. To circumvent this issue, we have set-up a computer tool called 'ExEnSo' (Expression Enhancer Software) that generates a random library of 8192 sequences, calculates the free energy of secondary structures of each sequence in the -70/+96 region (base 1 is the translation initiation codon), and then selects the sequence having the highest free energy. The software uses this 'optimized' sequence to create a 5' primer that can be used in PCR experiments to amplify the coding sequence of interest prior to sub-cloning into a prokaryotic expression vector. In this article, we report how ExEnSo was set-up and the results obtained with nine coding sequences with low expression levels in E. coli. The free energy of the -70/+96 region of all these coding sequences was increased compared to the non-optimized sequences. Moreover, the protein expression of eight out of nine of these coding sequences was increased in E. coli, indicating a good correlation between in silico and in vivo results. ExEnSo is available as a free online tool.

French adaptation of the "Frenchay Dysarthria Assessment 2" speech intelligibility test.

OBJECTIVES: Speech intelligibility can be defined as "the degree to which a speaker's intended message is recovered by a listener". Loss of intelligibility is one of the most frequent complaints in patients suffering from speech disorder, impairing communication. Measurement of intelligibility is therefore an important parameter in follow-up. We developed a French version of the "Frenchay Dysarthria Assessment, 2nd edition" (FDA-2), an intelligibility test recognized internationally in its English version. The present study details the construction of the test and its preliminary validation. MATERIALS AND METHODS: We first compiled a set of words and phrases in French, based on the criteria defined in FDA-2. In a second step, we validated the test in healthy subjects in normal and noisy conditions, to check sensitivity to speech signal degradation. RESULTS: The test proved valid and sensitive, as scores were significantly lower for noise-degraded stimuli. CONCLUSION: This French-language intelligibility test can be used to evaluate speech disorder: for example, in dysarthria, head and neck cancer or after cochlear implantation.

FIVHeMA: Intraventricular fibrinolysis versus external ventricular drainage alone in aneurysmal subarachnoid hemorrhage: A randomized controlled trial.

INTRODUCTION: Aneurysmal subarachnoid hemorrhage (SAH) is a devastating form of stroke, which often causes acute hydrocephalus requiring the insertion of an external ventricular drain (EVD). A major complication of aneurysmal SAH is delayed cerebral ischemia (DCI). As DCI is linked to the presence of blood within the subarachnoid space, it has been hypothesized that removing this blood may decrease the risk of DCI. This could be achieved by injecting a fibrinolytic agent through the EVD, a strategy called intraventricular fibrinolysis (IVF). Here, we propose to conduct a phase III trial to directly evaluate the impact of IVF after aneurysmal SAH. MATERIALS AND METHODS: We will perform an open-label randomized controlled trial comparing the standard of care, i.e. EVD alone, to the experimental treatment, i.e. IVF. We plan to include 440 patients to be able to show a 10% increase in the rate of good functional outcomes in the EVD+IVF group compared to the EVD alone group (α=0.05 and ß=0.8). To obtain such sample, a multicenter trial is required, and to date 17 research sites in France have agreed to participate. PERSPECTIVE: FIVHeMA would be the first phase III trial evaluating the relevance of IVF in aneurysmal SAH. If IVF is shown to be beneficial, then a new therapeutic tool will be available to improve the outcomes of aneurysmal SAH patients.

FDG PET-CT for solitary pulmonary nodule and lung cancer: Literature review.

The investigation of solitary pulmonary nodule (SPN) and non-small cell lung cancer (NSCLC) has rapidly become one of the main indications for 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET), currently combined with computed tomography (PET-CT). In this literature review, we first attempt to clarify how PET imaging contributes to investigating SPN, in conjunction with conventional CT. We highlight the prospects of research underway to improve our understanding of SPN. In the second part of this review, we analyze the current role of PET-CT in the overall care process for lung cancer. We review the indications for which consensus has been reached, for example initial staging, as well as new indications such as radiation therapy planning or prognostic assessment.

Dysregulation of IL-2/IL-2R system alters proliferation of early activated CD4+ T cell subset in patients with end-stage renal failure.

BACKGROUND/AIM: Although CD4+ T cells are preactivated in patients with end-stage renal failure (ESRF), these patients present an impairment of T cell immune response, which is partly responsible for the higher incidence of infection in this population. The aim of the present study was to analyze the mechanisms underlying the altered function of activated CD4+ T cells in patients with ESRF. METHODS: Thirty patients undergoing chronic hemodialysis (HD) and 20 patients with ESRF were compared with 15 sex- and age-matched controls. CD4+ T cell early activation (CD69, CD25), interleukin-2 (IL-2)/IL-2 receptor (IL-2R) system, and proliferation capacity of CD69+/CD4+ T cells were assessed ex vivo after blood draw sampling, in culture conditions and after phytohemagglutinin (PHA) stimulation. RESULTS: Although the CD4+ T cell count was lower in chronic HD patients than in predialysis patients and controls (p = 0.007), CD4+ T cells showed a pre-activation state as demonstrated by higher percentage of CD69+/CD4+ T cells and CD25+/CD4+ T cells in chronic HD patients compared with the other groups ex vivo. Furthermore, CD69+/CD4+ T cells from chronic HD patients spontaneously released more IL-2 (22 +/- 6 pg/ml) than those from pre-dialysis patients (12 +/- 4 pg/ml, p = 0.005) and controls (5 +/- 3 pg/ml, p = 0.001). However, after PHA stimulation, CD69+/CD4+ T cells from chronic HD patients expressed lower cell surface CD25 density, and were unable to show further activation. Indeed, these cells produced less IL-2 and released more soluble IL-2R, and correlatively with IL-2 production, they showed lower proliferation capacity compared with predialysis patients (p = 0.001) and controls (p < 0.001). They also displayed decreased responsiveness to exogenous human recombinant IL-2. The restoration of the PHA stimulation index of CD69+/CD4+ T cells from chronic HD patients in the presence of normal human serum as well as the decreased stimulation index of CD69+/CD4+ T cells from control subjects incubated with HD serum, strongly suggest that uremic toxins and mediators induced by HD affect the IL-2/IL-2R pathway. CONCLUSION: These findings demonstrate the presence, in chronic HD patients, and to lesser extent, in predialysis patients, of abnormally high proportion of spontaneously preactivated CD4+ T cells whose proliferation and further activation are blunted due to dysregulation of the IL-2/IL-2R system.

Comment on "Acoustical observation of bubble oscillations induced by bubble popping".

We have reproduced the experiment of acoustic monitoring of spontaneous popping of single soap bubbles standing in air reported by Ding et al. [2aaPhys. Rev. E 75, 041601 (2007)]. By using a single microphone and two different signal acquisition systems recording in parallel the signal at the microphone output, among them the system used by Ding et al., we have experimentally evidenced that the acoustic precursors of bubble popping events detected by Ding et al. actually result from an acausal artifact of the signal processing performed by their acquisition system which lies outside of its prescribed working frequency range. No acoustic precursor of popping could be evidenced with the microphone used in these experiments, whose sensitivity is 1VPa-1 and frequency range is 500 Hz-100 kHz.

Amyloid beta-peptide and oxidative cellular injury in Alzheimer's disease.

Alzheimer's disease is a progressive neurodegenerative disorder that affects primarily learning and memory functions. There is significant neuronal loss and impairment of metabolic functioning in the temporal lobe, an area believed to be crucial for learning and memory tasks. Aggregated deposits of amyloid beta-peptide may have a causative role in the development and progression of AD. We review the cellular actions of A beta and how they can contribute to the cytotoxicity observed in AD. A beta causes plasma membrane lipid peroxidation, impairment of ion-motive ATPases, glutamate uptake, uncoupling of a G-protein linked receptor, and generation of reactive oxygen species. These effects contribute to the loss of intracellular calcium homeostasis reported in cultured neurons. Many cell types other than neurons show alterations in the Alzheimer's brain. The effects of A beta on these cell types is also reviewed.

A modulation of glutamate-induced phosphoinositide breakdown by intracellular pH changes.

The influence of intracellular pH (pHi) changes on the formation of inositol phosphate metabolites (IPs) produced by glutamatergic stimulation was studied in 8-day-old rat brain synaptoneurosomes. For this purpose pHi was measured using 2',7'-bis-(2-carboxyl)-5,6-carboxyfluorescein (BCECF) fluorimetric assay in parallel with the basal and receptor-mediated formations of inositol monophosphate (IP1) and inositol bisphosphate (IP2). We found that glutamate (1 mM), which induces a transient acidification (delta pH = -0.05), produces an identical accumulation of IP1 and IP2. K+ (30 mM), which provokes an alkalinization of the internal medium (delta pH = +0.22), mainly leads to the formation of IP1 metabolites. Paired combinations of glutamate with 1, 5 and 10 mM NH4+ finally result in an alkalinization of the intrasynaptoneurosomal medium. These combinations produce a strong decrease of the IP2 level concomitant with an increase of the IP1 formation, compared to the levels of IP1 and IP2 evoked by glutamate alone. The total amount of IPs (IP1 + IP2) produced by these combinations is not different from that obtained with glutamate alone. Paired combinations of carbachol with NH4+ produce an identical alkalinization to that produced by NH4+ alone. These combinations produce an increased IP1 accumulation, while the IP2 formation is slightly decreased. When the internal medium is acidified by diminishing the external concentration of Na+, the ratio IP1/IP2 produced after metabotropic glutamate receptor (mGluR) activation is shifted to lower values, while it is not affected for the muscarinic stimulation. These data suggest that the mGluR-associated pathway in synaptoneurosomes is sensitive to pHi shifts, while the muscarinic receptor-associated pathway is less altered when pHi is manipulated. It may be proposed that pH-sensitive inositol phosphate dephosphorylating systems, i.e. phosphatases, are associated with mGluRs in this preparation.

4-Hydroxynonenal, an aldehydic product of membrane lipid peroxidation, impairs glutamate transport and mitochondrial function in synaptosomes.

Removal of extracellular glutamate at synapses, by specific high-affinity glutamate transporters, is critical to prevent excitotoxic injury to neurons. Oxidative stress has been implicated in the pathogenesis of an array of prominent neurodegenerative conditions that involve degeneration of synapses and neurons in glutamatergic pathways including stroke, and Alzheimer's, Parkinson's and Huntington's diseases. Although cell culture data indicate that oxidative insults can impair key membrane regulatory systems including ion-motive ATPases and amino acid transport systems, the effects of oxidative stress on synapses, and the mechanisms that mediate such effects, are largely unknown. This study provides evidence that 4-hydroxynonenal, an aldehydic product of lipid peroxidation, mediates oxidation-induced impairment of glutamate transport and mitochondrial function in synapses. Exposure of rat cortical synaptosomes to 4-hydroxynonenal resulted in concentration- and time-dependent decreases in [3H]glutamate uptake, and mitochondrial function [assessed with the dye 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)]. Other related aldehydes including malondialdehyde and hexanal had little or no effect on glutamate uptake or mitochondrial function. Exposure of synaptosomes to insults known to induce lipid peroxidation (FeSO4 and amyloid beta-peptide) also impaired glutamate uptake and mitochondrial function. The antioxidants propyl gallate and glutathione prevented impairment of glutamate uptake and MTT reduction induced by FeSO4 and amyloid beta-peptide, but not that induced by 4-hydroxynonenal. Western blot analyses using an antibody to 4-hydroxynonenal-conjugated proteins showed that 4-hydroxynonenal bound to multiple cell proteins including GLT-1, a glial glutamate transporter present at high levels in synaptosomes. 4-Hydroxynonenal itself induced lipid peroxidation suggesting that, in addition to binding directly to membrane regulatory proteins, 4-hydroxynonenal potentiates oxidative cascades. Collectively, these findings suggest that 4-hydroxynonenal plays important roles in oxidative impairment of synaptic functions that would be expected to promote excitotoxic cascades.

Protein kinase C differently regulates quisqualate- and 1S,3R-trans aminocyclopentane dicarboxylate-induced phosphoinositide hydrolysis during in vitro development of hippocampal neurons.

Transient peaks of quisqualate (QA)-, but not 1S,3R-1-amino-3-cyclopentane dicarboxylate (1S,3R-ACPD)- and carbachol-induced inositol phosphate formation occur between 2 and 5 days in vitro (DIV) in hippocampal neurons in culture. In order to elucidate the putative origin of such developmental activity differences, the effect of PKC on metabotropic glutamate receptor (mGluR) and muscarinic receptor responses was investigated at 3 and 10 DIV. (i) Stimulation of PKC by phorbol-12,13-dibutyrate inhibited QA, 1S,3R-ACPD and carbachol responses at 3 DIV. At 10 DIV, only 1S,3R-ACPD response was still inhibited by phorbol esters. (ii) Inhibition of PKC by staurosporine at 3 DIV potentiated 1S,3R-ACPD-induced inositol phosphate formation, but had no effect on QA and carbachol responses. At 10 DIV, all responses were potentiated by staurosporine. These data strongly suggest that PKC differently modulates 1S,3R-ACPD- and QA-induced inositol phosphate accumulations during in vitro development. The specific activity of mGluRs during development, vs that of muscarinic receptor, and the peculiar modes of regulation by PKC of these two mGluR activities further suggest their particular involvement in the maturation of neuronal culture.

Intra- vs extracellular calcium regulation of neurotransmitter-stimulated phosphoinositide breakdown.

The dependence on Ca2+ of basal, glutamate- and carbachol-stimulated phosphoinositide (PI) turnover was studied on 8-day old rat brain synaptoneurosomes. For that purpose, intracellular and extracellular Ca2+ concentrations were buffered by bis-(alpha-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid, in its tetra(acetoxymethyl)-ester form (BAPTA-AM) and in its free acid form (BAPTA), respectively. The effects of both forms of the calcium chelator intracellular and extracellular Ca2+ buffering on intracellular and extracellular Ca2+ concentration ([Ca2+]i and [Ca2+]e) were determined with fluorimetric assay using fura2, either in its acetoxymethyl ester form (fura2-AM) or in its free acid form. Intracellular chelation of Ca2+ ions with BAPTA-AM induced a dose-dependent reduction of the [Ca2+]i. Basal inositol phosphate (IP) formation was slightly affected by this [Ca2+]i buffering, while glutamate and carbachol stimulations of PI hydrolysis were similarly diminished. Chelation of extracellular Ca2+ ions with BAPTA produced a reduction of both [Ca2+]e and [Ca2+]i. Basal IP accumulation was maximally inhibited by 50%. The carbachol-induced PI hydrolysis was completely inhibited in the presence of 200 microM BAPTA, while a substantial residual glutamate-elicited IP response remained (40% of the control response). It is concluded that [Ca2+]i of synaptoneurosomes is not critical for basal and neurotransmitter-stimulated IP formation, whilst [Ca2+]e is critical. Glutamate may, in part, stimulate PI breakdown in a Ca(2+)-insensitive way.

Cadmium rapidly and irreversibly blocks presynaptic phospholipase C-linked metabotropic glutamate receptors.

Calcium ions (Cd2+) inhibit inositol phosphate (IP) formation elicited by glutamate (GLU) or K+ ions, without affecting carbachol (Carb)-induced IP response in 8-day-old rat forebrain synaptoneurosomes and synaptosomes. On the contrary, Cd2+ was almost ineffective in blocking GLU- and K(+)-responses in hippocampal neurones in culture. The mechanism of Cd2+ inhibition was thus examined in synaptoneurosomes. Extensive washing of synaptoneurosomes pretreated for 1, 5, 15, or 30 min by 100 microM Cd2+ did not modify the inhibitory effect of Cd2+ on GLU-, K(+)- and A23187-evoked IP formation or its lack of effect on Carb response. The later addition of a high affinity Cd2+ chelator (100 microM), N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) also did not reverse the inhibitory effect. TPEN, however, penetrates into synaptoneurosomes and efficiently displaces Cd2+ from the Fura-2-Cd2+ complex as shown by Fura-2 fluorescence recordings. TPEN is not easily removed from the intracellular space, as demonstrated by its ability to still block Cd(2+)-induced Fura-2 fluorescence increase after extensive washing. Pretreatment of synaptoneurosomes by this chelator did not prevent Cd2+ inhibition of GLU-induced IP formation. These data indicate that Cd2+ ions rapidly, irreversibly and extracellularly inhibit GLU-elicited IP formation in synaptoneurosomes or synaptosomes, but not in hippocampal neurones in culture. It is speculated that Cd2+ ions could allow one to distinguish the activity of presynaptic metabotropic glutamate receptors (mGLURs) linked to phosphoinositide metabolism from that of mGLURs located postsynaptically.

Excitatory amino acid-, except 1S,3R-ACPD, induced transient high stimulation of phosphoinositide metabolism during hippocampal neuron development.

Rat hippocampal neurons in culture extended their neurites until day 5 in vitro (DIV). Then, the mean neuritic length slightly decreased. Excitatory amino acid (EAA)-elicited inositol phosphate (IP) formation increased from 0.5 to 2 DIV, reached a plateau between 2 and 4-5 DIV, and then gradually decreased until 10 DIV. This decrease was likely not due to neuronal death. This developmental pattern was observed for N-methyl-D-aspartate, kainate, glutamate, ibotenate and quisqualate (QA). Interestingly, the 1S,3R-aminocyclopentane dicarboxylate (1S,3R-ACPD) response slightly increased during neuronal culture development. At 3 DIV, the ionotropic antagonists 6,7-dinitro-quinoxalin-2,3-dion and D-2-amino-5-phosphonopentanoate efficiently blocked N-methyl-D-aspartate and kainate-elicited IP formation, and partially inhibited glutamate and ibotenate responses. QA and 1S,3R-ACPD responses were not affected, suggesting a metabotropic action for these two compounds. Furthermore, QA and 1S,3R-ACPD potencies significantly increased between 3 and 10 DIV. The transient high activity periods induced by EAA, except for 1S,3R-ACPD, are not observed for norepinephrine, carbachol and potassium chloride responses. Taken together, these data suggest that: (i) QA and 1S,3R-ACPD can act on two different glutamate metabotropic receptors subtypes during development; and (ii) the EAA-induced transient peaks of IP stimulation, which are specific with respect to other neuroactive substances profiles, could be involved in the development of hippocampal neurons. Indeed, these transient high activities take place when the neuritic length regularly increases in vitro.

Unusual aspects of the dialysis disequilibrium syndrome.

In five patients with chronic renal failure, rapid correction by dialysis of hypertension and/or high blood urea levels provoked acute neurological disorders, followed by slowly reversible neuropsychiatric disturbances. Focal EEG alterations were noted in three patients with normal carotid angiograms. Our cases differed from those usually described as suffering from the dialysis disequilibrium syndrome because of their duration, the severity of mental disturbances, and the asymmetrical pattern of EEG abnormalities. We propose that the symptoms observed could be due to cerebral ischemia. This possibility emphasizes the importance of limiting the duration and efficiency of the first dialyses in patients with severe hypertension and high nitrogen retention, especially if high performance dialyzers are used.

Prostatic tissue destruction by high-intensity focused ultrasound: experimentation on canine prostate.

High-intensity focused ultrasound (HIFU) has been used transrectally to induce intraprostatic coagulation necrosis lesion in the canine prostate. The device combines a firing system (power amplifier and therapy transducer) and a localization system (ultrasound scanner). Thirty-seven dogs have been treated with ultrasound intensity ranging from 720 W/cm2 to 2300 W/cm2 and shot durations ranging from 1 to 4 seconds. The threshold for focal ultrasonic lesions was determined to be 1000 W/cm2 with a 1-second shot duration. Intraprostatic lesions were obtained without any damage to the rectal wall. These lesions were homogeneous coagulation necroses and progressed first to an inflammatory fibrosis and then to sclerosis with cavity formation. Intraprostatic lesions also occurred with a combination of moderate acoustic intensity (720 W/cm2) and longer shot duration (4 seconds). The temperature reached at the focal point of the transducer was 85 degrees C. The study confirms the possibility of creating irreversible lesions in the prostatic tissue through the rectal wall. The destruction of localized prostatic cancer seems to be possible in the near future using HIFU delivered by the transrectal route.

Orientational disorder as a function of temperature in the clathrate structure of hydroquinone and C60

In the compound [C(6)H(6)O(2)](3)C(60), hydroquinone (C(6)H(6)O(2)) forms a three-dimensional hydrogen-bonded network enclosing roughly spherical cages with point symmetry 3;m and a diameter of 13.2 A at 100 K. Although C(60) fits tightly into these cages, it shows threefold orientational disorder, the molecular site symmetry being 2/m. The disorder has been studied with single-crystal Mo Kalpha X-ray data at four temperatures, 100, 200, 293 and 373 K. In the refinement, C(60) was restrained to the icosahedral molecular symmetry m3;5; and to rigid-body translational and librational displacements including third- and fourth-order cumulants to account for curvilinear atomic movements, R(|F|) = 3.2-4.7%. At 100 K, bond lengths in C(60) refine to the expected values 1.450 (1) and 1.388 (1) A. The ratio of these values increases with increasing temperature, but the radius of the molecule remains constant at 3. 537 (2) A. The r.m.s. libration amplitudes of C(60) are relatively small (5.5 degrees at 373 K) and the probability function of orientations of C(60) inside the cage shows large values only at the refined positions, indicating that the energy barrier of reorientation is large. Refinement of an ordered twinned structure was unsuccessful; the orientations of neighboring C(60) appear to be uncorrelated.