Potential use of TG68 - A novel thyromimetic - for the treatment of non-alcoholic fatty liver (NAFLD)-associated hepatocarcinogenesis

Introduction

Several lines of evidence suggest that the thyroid hormone signaling pathway is altered in patients with NAFLD and that pharmacological strategies to target the thyroid hormone/thyroid hormone nuclear receptor axis (TH/THR) in the liver may exert beneficial effects. In this study, we investigated the effect of TG68, a novel THRβ agonist, on rat hepatic fat accumulation and NAFLD-associated hepatocarcinogenesis.

Methods

Male rats given a single dose of diethylnitrosamine (DEN) and fed a high fat diet (HFD) were co-treated with different doses of TG68. Systemic and hepatic metabolic parameters, immunohistochemistry and hepatic gene expression were determined to assess the effect of TG68 on THRβ activation.

Results

Irrespectively of the dose, treatment with TG68 led to a significant reduction in liver weight, hepatic steatosis, circulating triglycerides, cholesterol and blood glucose. Importantly, a short exposure to TG68 caused regression of DEN-induced preneoplastic lesions associated with a differentiation program, as evidenced by a loss of neoplastic markers and reacquisition of markers of differentiated hepatocytes. Finally, while an equimolar dose of the THRβ agonist Resmetirom reduced hepatic fat accumulation, it did not exert any antitumorigenic effect.

Discussion

The use of this novel thyromimetic represents a promising therapeutic strategy for the treatment of NAFLD-associated hepatocarcinogenesis.

Design, Synthesis, and In Vitro Evaluation of Novel 8-Amino-Quinoline Combined with Natural Antioxidant Acids

Overproduction of reactive oxygen species (ROS) and alterations in metallostasis are common and related hallmarks in several neurodegenerative diseases (NDDs). Nature-based derivatives always represent an attractive tool in MTDL drug design, especially against ROS in NDDs. On this notion, we designed a new series of 8-quinoline-N-substituted derivatives with a natural antioxidant portion (i.e., lipoic, caffeic, and ferulic acids). These compounds were shown to chelate copper, a metal involved in ROS-induced degeneration, and scavenger oxygen radicals in DPPH assay. Then, selected compounds 4 and 5 were evaluated in an in vitro model of oxidative stress and shown to possess cytoprotective effects in 661W photoreceptor-like cells. The obtained results may represent a starting point for the application of the proposed class of compounds in retinal neurodegenerative diseases such as retinitis pigmentosa (RP), comprising a group of hereditary rod–cone dystrophies that represent a major cause of blindness in patients of working age, where the progression of the disease is a multifactorial event, with oxidative stress contributing predominantly.

Identification of a Thyroid Hormone Derivative as a Pleiotropic Agent for the Treatment of Alzheimer's Disease

The identification of effective pharmacological tools for Alzheimer's disease (AD) represents one of the main challenges for therapeutic discovery. Due to the variety of pathological processes associated with AD, a promising route for pharmacological intervention involves the development of new chemical entities that can restore cellular homeostasis. To investigate this strategy, we designed and synthetized SG2, a compound related to the thyroid hormone thyroxine, that shares a pleiotropic activity with its endogenous parent compound, including autophagic flux promotion, neuroprotection, and metabolic reprogramming. We demonstrate herein that SG2 acts in a pleiotropic manner to induce recovery in a C. elegans model of AD based on the overexpression of Aβ42 and improves learning abilities in the 5XFAD mouse model of AD. Further, in vitro ADME-Tox profiling and toxicological studies in zebrafish confirmed the low toxicity of this compound, which represents a chemical starting point for AD drug development.

Development of potent dual PDK1/AurA kinase inhibitors for cancer therapy: Lead-optimization, structural insights, and ADME-Tox profile

We report the synthesis of novel first-in-class 2-oxindole-based derivatives as dual PDK1-AurA kinase inhibitors as a novel strategy to treat Ewing sarcoma. The most potent compound 12 is suitable for progression to in vivo studies. The specific attributes of 12 included nanomolar inhibitory potency against both phosphoinositide-dependent kinase-1 (PDK1) and Aurora A (AurA) kinase, with acceptable in vitro ADME-Tox properties (cytotoxicity in 2 healthy and 14 hematological and solid cancer cell-lines; inhibition of PDE4C1, SIRT7, HDAC4, HDAC6, HDAC8, HDAC9, AurB, CYP1A2, CYP2C9, CYP2C19, CYP2D6, and hERG). X-ray crystallography and docking studies led to the identification of the key AurA and PDK1/12 interactions. Finally, in vitro drug-intake kinetics and in vivo PK appear to indicate that these compounds are attractive lead-structures for the design and synthesis of PDK1/AurA dual-target molecules to further investigate the in vivo efficacy against Ewing Sarcoma.

Beyond Antioxidant Effects: Nature-Based Templates Unveil New Strategies for Neurodegenerative Diseases

The complex network of malfunctioning pathways occurring in the pathogenesis of neurodegenerative diseases (NDDs) represents a huge hurdle in the development of new effective drugs to be used in therapy. In this context, redox reactions act as crucial regulators in the maintenance of neuronal microenvironment homeostasis. Particularly, their imbalance results in the severe compromising of organism’s natural defense systems and subsequently, in the instauration of deleterious OS, that plays a fundamental role in the insurgence and progress of NDDs. Despite the huge efforts in drug discovery programs, the identification process of new therapeutic agents able to counteract the relentless progress of neurodegenerative processes has produced low or no effective therapies. Consequently, a paradigm-shift in the drug discovery approach for these diseases is gradually occurring, paving the way for innovative therapeutical approaches, such as polypharmacology. The aim of this review is to provide an overview of the main pharmacological features of most promising nature-based scaffolds for a possible application in drug discovery, especially for NDDs, highlighting their multifaceted effects against OS and neuronal disorders.

Results and predictors of outcome of endoscopic endonasal surgery in Cushing's disease: 20-year experience of an Italian referral Pituitary Center

PURPOSE

To assess outcomes and predictors of early and long-term remission in patients with Cushing's disease (CD) due to ACTH-secreting adenomas treated via endoscopic endonasal approach (EEA).

METHODS

This is a retrospective study. Consecutive patients operated for CD from 1998 to 2017 in an Italian referral Pituitary Center were enrolled. Clinical, radiological, and histological data at enrollment and follow-up were collected.

RESULTS

151 patients (107 F) were included; 88.7% were naïve for treatment, 11.3% had been treated surgically and 11.2% medically. At pre-operative magnetic resonance imaging (MRI), 35 had a macroadenoma and 80 a microadenoma, while tumor was undetectable in 36 patients. Mean age at surgery was 41.1 ± 16.6 years. Diagnosis was confirmed histologically in 82.4% of the cases. Patients with disease persistence underwent second surgery and/or medical and/or radiation therapy. Mean follow-up was 92.3 ± 12.0 (range 12-237.4) and median 88.2 months. Remission rate was 88.1% after the first surgery and 90.7% at last follow-up. One patient died of pituitary carcinoma. Post-surgical cortisol drop (p = 0.004), tumor detection at MRI (p = 0.03) and size < 1 cm (p = 0.045) increased the chance of disease remission; cavernous sinus invasion was a negative predictor of outcome (p = 0.002). Twenty-seven patients developed diabetes insipidus and 18 hypopituitarism. Surgery repetition increased the risk of hypopituitarism (p = 0.03), but not of other complications, which included epistaxis (N = 2), cerebrospinal fluid leakage (1), pneumonia (3), myocardial infarction (1), and pulmonary embolisms (2).

CONCLUSIONS

Selective adenomectomy via EEA performed by experienced surgeons, supported by a multidisciplinary dedicated team, allows long-term remission in the vast majority of CD patients with low complication rate.

Application of intravoxel incoherent motion (IVIM) magnetic resonance imaging in the evaluation of primitive brain tumours

Intravoxel incoherent motion is a potential non-invasive diagnostic tool in brain tumours, without any clear guidelines for its evaluation yet. In our study, we compare intravoxel incoherent motion with dynamic susceptibility contrast magnetic resonance imaging in the quantification of tumour tissue blood perfusion in 28 patients affected by brain tumours, highlighting the issues encountered during the acquisition set-up and post-processing steps. Intravoxel incoherent motion is a new imaging tool and an alternative technique to dynamic susceptibility contrast-magnetic resonance imaging which is of considerable interest at present. This is partly because it does not require the use of a contrast agent and relies on the intrinsic properties of motion in the capillaries of the spins. Compared to dynamic susceptibility contrast-magnetic resonance imaging, the intravoxel incoherent motion technique is also characterised by better resolution because the gadolinium-based contrast agent bolus used in the standard technique results in a variation by more than 50% of the signal coming from the brain. Finally, intravoxel incoherent motion is more sensitive to the incoherent motion that originates from small capillary vessels, while the dynamic susceptibility contrast signal is also contaminated by the input from larger arteries and veins, which may result in an overestimation of the blood volume. Although there are limitations due to the heterogeneity of the sample considered in our study, intravoxel incoherent motion has been shown to be an accurate noninvasive radiological biomarker, useful to distinguish between low and high grade glial tumours.

Lo studio neuroradiologico dell'idrocefalo Valutazione pre- e post-chirurgica con particolare riguardo all'approccio endoscopico

La studio neuroradiologico dell'idrocefalo nell'epoca dei trattamenti chirurgici endoscopici si arricchisce di nuovi quesiti e di nuovi segni.

Se la TC mantiene la sua validità nella prima diagnosi di idrocefalo e nello studio delle complicanze immediate dei trattamenti endoscopici, perde il ruolo preminente che aveva nei controlli post-operatori a medio e lungo termine.

La RM è l'esame di scelta in fase prechirurgica, per la pianificazione dell'intervento endoscopico, con lo studio dell'anatomia della regione del III ventricolo. Lo stesso discorso vale per i controlli post-chirurgici delle terzoventricolostomie, vista la maggiore importanza del dato funzionale della pervietà della stomia rispetto al semplice dato morfologico della variazione della volumetria ventricolare.

Gli studi quantitativi con sequenze specifiche per il flusso e con sincronizzazione cardiaca, eventualmente abbinati alla funzione cine, sono indubbiamente accurati, raffinati ed eleganti, ma non indispensabili, nella pratica clinica, per lo studio del flusso liquorale; infatti non si è ancora dimostrata una loro significativa maggiore sensibilità rispetto ai dati qualitativi (flusso si/flusso no) ottenibili con normali sequenze FSE e TSE T2 w.

Two-Color Radiation Generated in a Seeded Free-Electron Laser with Two Electron Beams

We present the experimental evidence of the generation of coherent and statistically stable two-color free-electron laser radiation obtained by seeding an electron beam double peaked in energy with a laser pulse single spiked in frequency. The radiation presents two neat spectral lines, with time delay, frequency separation, and relative intensity that can be accurately controlled. The analysis of the emitted radiation shows a temporal coherence and a shot-to-shot regularity in frequency significantly enhanced with respect to the self-amplified spontaneous emission.

Novel schemes for the optimization of the SPARC narrow band THz source

A pulsed, tunable, narrow band radiation source with frequency in the THz region can be obtained collecting the coherent transition radiation produced by a train of ultra-short electron bunches having picosecond scale inter-distance. In this paper, we review the techniques feasible at the SPARC_LAB test facility to produce and manipulate the requested train of electron bunches and we examine the dynamics of their acceleration and compression. In addition, we show how the performances of the train compression and the radiation intensity and bandwidth can be significantly improved through the insertion of a fourth order harmonic cavity, working in the X-band and acting as a longitudinal phase space linearizer.

Pattern of care and effectiveness of treatment for glioblastoma patients in the real world: Results from a prospective population-based registry. Could survival differ in a high-volume center?

BACKGROUND

As yet, no population-based prospective studies have been conducted to investigate the incidence and clinical outcome of glioblastoma (GBM) or the diffusion and impact of the current standard therapeutic approach in newly diagnosed patients younger than aged 70 years.

METHODS

Data on all new cases of primary brain tumors observed from January 1, 2009, to December 31, 2010, in adults residing within the Emilia-Romagna region were recorded in a prospective registry in the Project of Emilia Romagna on Neuro-Oncology (PERNO). Based on the data from this registry, a prospective evaluation was made of the treatment efficacy and outcome in GBM patients.

RESULTS

Two hundred sixty-seven GBM patients (median age, 64 y; range, 29-84 y) were enrolled. The median overall survival (OS) was 10.7 months (95% CI, 9.2-12.4). The 139 patients ≤aged 70 years who were given standard temozolomide treatment concomitant with and adjuvant to radiotherapy had a median OS of 16.4 months (95% CI, 14.0-18.5). With multivariate analysis, OS correlated significantly with KPS (HR = 0.458; 95% CI, 0.248-0.847; P = .0127), MGMT methylation status (HR = 0.612; 95% CI, 0.388-0.966; P = .0350), and treatment received in a high versus low-volume center (HR = 0.56; 95% CI, 0.328-0.986; P = .0446).

CONCLUSIONS

The median OS following standard temozolomide treatment concurrent with and adjuvant to radiotherapy given to (72.8% of) patients aged ≤70 years is consistent with findings reported from randomized phase III trials. The volume and expertise of the treatment center should be further investigated as a prognostic factor.

Observation of time-domain modulation of free-electron-laser pulses by multipeaked electron-energy spectrum

We present the experimental demonstration of a new scheme for the generation of ultrashort pulse trains based on free-electron-laser (FEL) emission from a multipeaked electron energy distribution. Two electron beamlets with energy difference larger than the FEL parameter ρ have been generated by illuminating the cathode with two ps-spaced laser pulses, followed by a rotation of the longitudinal phase space by velocity bunching in the linac. The resulting self-amplified spontaneous emission FEL radiation, measured through frequency-resolved optical gating diagnostics, reveals a double-peaked spectrum and a temporally modulated pulse structure.

Anti-Ri-associated paraneoplastic cerebellar degeneration. Report of a case and revision of the literature

Paraneoplastic cerebellar degeneration associated with anti-Ri antibodies mainly presents with opsoclonus-myoclonus-ataxia. We report here the case of a patient with anti-Ri-antibody paraneoplastic syndrome, who presented four years after treatment for small-cell lung cancer (SCLC) with oscillopsia and gait disorder. On neurological examination vertical nystagmus, ataxic gait and postural tremor of all four limbs was detected. He died one year after the onset of the symptoms because of a acute exacerbation of his severe chronic obstructive pulmonary disease. No SCLC relapse or new cancer has been detected during the one-year follow-up period.To our knowledge, our patient is the first case of anti-Ri associated disorder with oscillopsia and vertical nystagmus as the initially prominent clinical features. The findings of this case study support the variability of anti-Ri-antibody-associated paraneoplastic syndrome. Further studies must be directed to better characterize the mechanisms underlying this syndrome. Finally, paraneoplastic neurological syndromes should be kept in mind also when a neoplastic disease is not demonstrated.

Metabolic abnormalities in pain-processing regions of patients with fibromyalgia: a 3T MR spectroscopy study

BACKGROUND AND PURPOSE

A growing body of evidence suggests the involvement of the brain in FM. The purpose of this proton MRS study was to test the hypothesis that there are metabolic alterations in some brain regions processing pain (VLPFC and thalamus) in patients with FM compared with HC.

MATERIALS AND METHODS

Twelve patients with FM (30-54 years of age; mean age, 43.2 years), and 12 HC, matched for age and sex, underwent 1 session of single-voxel MRS performed on a 3T MR imaging scanner. MRS spectra were acquired with a PRESS for localization. The raw data from each spectrum was evaluated with an LCModel. T tests were used to evaluate differences of brain metabolites between groups. The Pearson correlation tested the relationship of metabolite ratios and clinical symptoms.

RESULTS

Glx/Cr and Glu/Cr ratios within the VLPFC of both sides were significantly higher in patients than in HC (P < .01). No significant differences of metabolites between groups were found in the thalami. Positive correlations were found between Glu/Cr in the left thalamus and the VAS for pain (r = 0.730, P = .007) and between mIns/Cr in the right VLPFC and the VAS for pain (r = 0.607, P = .037) and the FIQ (r = 0.719, P = .008).

CONCLUSIONS

The presence of elevated Glu/Cr levels in VLPFC strengthens the opinion that a complex neurophysiologic imbalance of different brain areas involved in pain processing underlies FM. These data may be useful in the diagnosis and development of more effective pharmacologic treatments.

Self-amplified spontaneous emission free-electron laser with an energy-chirped electron beam and undulator tapering

We report the first experimental implementation of a method based on simultaneous use of an energy chirp in the electron beam and a tapered undulator, for the generation of ultrashort pulses in a self-amplified spontaneous emission mode free-electron laser (SASE FEL). The experiment, performed at the SPARC FEL test facility, demonstrates the possibility of compensating the nominally detrimental effect of the chirp by a proper taper of the undulator gaps. An increase of more than 1 order of magnitude in the pulse energy is observed in comparison to the untapered case, accompanied by FEL spectra where the typical SASE spiking is suppressed.

Experimental demonstration of emittance compensation with velocity bunching

In this Letter we report the first experiments aimed at the simultaneous demonstration of the emittance compensation process and velocity bunching in a high brightness electron source, the SPARC photoinjector in INFN-LNF. While a maximum compression ratio up to a factor 14 has been observed, in a particular case of interest a compression factor of 3, yielding a slice current of 120 A with less than 2 microm slice emittance, has been measured. This technique may be crucial in achieving high brightness beams in photoinjectors aiming at optimized performance of short wavelength single-pass free electron lasers or other advanced applications in laser-plasma accelerators.

Potential of high field functional MRI in the neuroradiological diagnosis of brain tumours

Functional 3 tesla magnetic resonance imaging (MRI) techniques such as diffusion and perfusion imaging and MR spectroscopy (MRS) allow a more accurate diagnosis of central nervous system tumours. This retrospective study analysed the MRI scans of 121 consecutive patients with a diagnosis of glial brain tumours who underwent surgery and/or biopsy and whose histological reports were available. Our aim was to establish if and how functional MRI techniques had enhanced the diagnostic accuracy with respect to morphological examination. To quantify the diagnostic contribution of these techniques and their predictive value, a questionnaire was compiled by an observer blinded to the neuroradiological diagnosis and to the histological results after surgery/biopsy. Patients were divided into two groups based on the time of 3T MRI examination performed: before or after surgery/biopsy. In the group of non-operated patients low grade gliomas could be distinguished from high grade malignant tumours, whereas in the group of operated patients signs of tumour persistence or recurrence could be distinguished from the effects of previous treatments. Functional MRI techniques improved the accuracy of diagnosis with respect to morphological examination alone in both groups of patients: areas of increased cellularity, neoangiogenesis or metabolic changes were identified confirming diagnosis, whereas methodological errors were disclosed in cases of incorrect diagnosis.

MGMT methylation status as a prognostic factor in anaplastic astrocytomas

2052

Background: MGMT methylation status has been found to be an important prognostic factor in glioblastoma patients (pts). However, further data on the epigenetic feature are needed before its role in rare diseases such as anaplastic astrocytomas (AA) can be established. Methods: A retrospective analysis was made on a database of 139 AA pts followed prospectively from January 1995 and August 2008. We evaluated only pts who met the following inclusion criteria: age >18 years; PS 0–2; histological diagnosis of AA; postoperative radiotherapy (RT) and chemotherapy (CT). MGMT status was determined with methylation specific PCR. The study aim was to evaluate the role of MGMT methylation status in AA. The log-rank test was employed to evaluate the significance of the prognostic variables. Results: 80 pts (m/f: 46/34, median age: 41 years, range: 18–71 years) were enrolled. MGMT was assessable in 71 of 80 pts (88.8%), being methylated in 30 (42.9%), and unmethylated in 41 (57.7%) pts. Median PFS was 48.6 months (95% CI: 33.7 - 63.5), being 96 months (95% CI: 29–163) and 38 months (95%CI: 18.9–57.2) in MGMT methylated and unmethylated pts, respectively (p = 0.09). At univariate analysis, complete resection (p = 0.02), age (p = 0.002), and KPS (p = 0.003) were significantly correlated with PFS. At multivariate analysis only age remains correlated with PFS (p = 0.01). Median survival (OS) was 93.7 months (95% CI: 63.5–123.8), being not reached and 77 months (95% CI: 20–134.2), in MGMT methylated and unmethylated pts, respectively (p = 0.03). MGMT methylation (p = 0.03), age (p = 0.0003), and KPS (p = 0.03) were significantly correlated with OS at univariate analysis. At multivariate analysis, age (p = 0.0002) and MGMT methylation (p = 0.01) were correlated with a better OS. Conclusions: MGMT methylation status is an independent prognostic factor together with age in AA. This datum should provide the background to improve the therapeutic index with temozolomide concurrent with and adjuvant to RT in AA.

No significant financial relationships to disclose.

Importance of functional MRI and the role of stereotactic biopsy in the diagnosis of cerebral lymphoma

Primary cerebral lymphoma has varied clinical and imaging presentations making the neuroradiologic diagnosis of primary cerebral lymphoma a challenge. We discuss here three cases of cerebral lymphoma, one primary and two secondary. Our aim is to highlight the importance of diffusion, perfusion and spectroscopy in addition to conventional morphological MRI, and the role of stereotactic biopsy in reaching a correct diagnosis.

Analysis methodology of movable emittance-meter measurements for low energy electron beams

The design of photoinjectors for modern free electron laser linac relies heavily on particular beam behavior in the few meters after the gun. To experimentally characterize it a movable emittance meter was proposed and built [L. Catani et al., Rev. Sci. Instrum. 77, 093301 (2006)] based on the beam slicing technique. This paper addresses all the aspects of analysis of the data acquired with the emittance meter and common to any slit based emittance measurement for low energy beams.

Direct measurement of the double emittance minimum in the beam dynamics of the sparc high-brightness photoinjector

In this Letter we report the first experimental observation of the double emittance minimum effect in the beam dynamics of high-brightness electron beam generation by photoinjectors; this effect, as predicted by the theory, is crucial in achieving minimum emittance in photoinjectors aiming at producing electron beams for short wavelength single-pass free electron lasers. The experiment described in this Letter was performed at the SPARC photoinjector site, during the first stage of commissioning of the SPARC project. The experiment was made possible by a newly conceived device, called an emittance meter, which allows a detailed and unprecedented study of the emittance compensation process as the beam propagates along the beam pipe.

Meeting the need for emergency obstetric care in Mozambique: work performance and histories of medical doctors and assistant medical officers trained for surgery

OBJECTIVE

Nonphysicians in Mozambique have been performing major surgery for more than 20 years, with documented outcomes equivalent to those of specialists. The purpose of this study was to make an inventory of all government hospitals so as to document obstetric surgery performed by 'técnicos de cirurgia' (TCs) and to elucidate their retention at district level.

DESIGN

Cross-sectional study of surgical procedures during 2002; longitudinal study of TCs and doctors graduating in 1987, 1988 and 1996.

SETTING

All 34 hospitals with an operating theatre in Mozambique.

POPULATION

Records of 12,178 major surgical obstetric operations were examined, and 59 medical officers and 34 TCs were interviewed.

METHODS

Analysis of all surgical registers during 2002 in all government rural, provincial, general and central hospitals in Mozambique. TCs and doctors who had graduated in the specified years were traced and interviewed; health ministry records were reviewed to confirm assignments.

MAIN OUTCOME MEASURES

Proportion of major obstetric surgeries performed by TCs. Proportion of TCs and medical doctors still at rural/district level at 7 years after graduation.

RESULTS

Major obstetric surgery is conducted by nonphysicians in 57% of the 12,178 operations scrutinised. In district hospitals, they conducted 92% of 3246 operations. Retention of TCs and medical doctors at district hospital level differed markedly: after 7 years, 88% of the TCs remained in post compared with none of the medical doctors.

CONCLUSION

Nonphysicians, trained in surgery, do most of the emergency obstetric surgery in Mozambique, and almost all of that performed in district hospitals. Nonphysicians, compared with physicians, stay longer in rural areas. After 7 years, around 90% of nonphysicians are still working in district hospitals, while almost no physicians remain there.

Metabolic findings on 3T 1H-MR spectroscopy in peritumoral brain edema

BACKGROUND AND PURPOSE

Little is known about the metabolic properties of brain edema associated with tumors. This work was conducted on the basis of the assumption that, in the presence of intra-axial and extra-axial brain tumors, the white matter involved by the edema is a site of metabolic change that involves the structure of the myelin sheath.

MATERIALS AND METHODS

Thirteen patients comprised our cohort affected by intra-axial and extra-axial cerebral tumors with a peritumoral T2-weighted MR signal hyperintensity as a result of edema, where MR spectroscopy showed no increase in choline-containing compounds. Measurements on proton MR spectroscopy (1H-MR spectroscopy) were performed with a 3T whole-body scanner with use of a point-resolved spectroscopy sequence for localization (TR, 2000 ms; TE, 35 ms), and the metabolites were quantified with the SAGE method. Peak intensities of the main metabolites were expressed as ratios of one another and were compared with values obtained in the white matter of the left frontal region in a control group of 16 healthy volunteers.

RESULTS

Choline-to-creatine (Cho/Cr) and myo-inositol-to-creatine (mIns/Cr) signal intensity ratios were normal in all patients. N-acetylaspartate-to-creatine (NAA/Cr) and N-acetylaspartate-to-choline (NAA/Cho) ratios decreased in 4 patients. Glutamate plus glutamine-to-creatine (Glx/Cr) was increased in 10 patients. A resonance peak at 3.44 ppm, strongly suggesting the presence of glucose, was detected in all but 1 patient. Lactate was detected in 12 patients and lipids in 5. Moreover, the resonances that pertained to the aliphatic amino acids valine, leucine, and isoleucine were present in 12 patients.

CONCLUSIONS

Our findings on MR spectroscopy confirmed the hypothesis that in the edema surrounding brain tumors, an energy-linked metabolic alteration was associated with injury to the myelin sheath.

Lack of association between mtDNA haplogroups and Alzheimer’s disease in Tuscany

Mitochondrial DNA (mtDNA) haplogroup-specific polymorphisms were previously related to several neurodegenerative diseases, including Alzheimer's disease (AD). However, the precise role of mtDNA haplogroups in the neurodegenerative cascade leading to AD is still unclear. In this work we have genotyped predefined European mtDNA haplogroups in 209 patients with AD and 191 matched controls. In order to minimise the risk of "genetic contamination", which could lead to false associations between gene markers and disease, we were careful to enrol in the study only patients and controls of clear Tuscan origin (with at least three generations of Tuscanborn relatives). The frequency of the haplogroups did not differ between the two groups, and no correlation with gender, ApoE genotype, age of onset or disease status was observed. Further studies will be required to define the contribution of mtDNA haplogroups, if any, to the pathogenesis of AD. A correct population selection, in order to minimise the risk of genetic contamination, is essential in these studies.

Association of the hOGG1 Ser326Cys polymorphism with sporadic amyotrophic lateral sclerosis

Amyotropic lateral sclerosis (ALS) is a fatal and progressive neurodegenerative disease causing the loss of motoneurons of the brain and the spinal cord. The etiology of ALS is still uncertain, but males are at increased risk for the disease than females. Several studies have suggested that motoneurons in ALS might be subjected to the double insult of increased DNA oxidative damage and deficiencies in DNA repair systems. Particularly, increased levels of 8-oxoguanine and impairments of the DNA base excision repair system have been observed in neurons of ALS patients. There is evidence that the Ser326Cys polymorphism of the human 8-oxoguanine DNA glycosylase 1 (hOGG1) gene is associated with a reduced DNA repair activity. To evaluate the role of the hOGG1 Ser326Cys polymorphism in sporadic ALS (sALS), we screened 136 patients and 129 matched controls. In the total population, we observed association between both the Cys326 allele (p=0.02) and the combined Ser326Cys+Cys326Cys genotype (OR=1.65, 95% CI=1.06-2.88) and increased risk of disease. After stratification by gender, the Cys326 allele (p=0.01), both the Ser326Cys genotype (OR=2.14, 95% CI=1.09-4.19) and the combined Ser326Cys+Cys326Cys genotype (OR=2.15, 95% CI=1.16-4.01) were associated with sALS risk only in males. No significant association between the Ser326Cys polymorphism and disease phenotype, including age and site of onset and disease progression, was observed. Present results suggest a possible involvement of the hOGG1 Ser326Cys polymorphism in sALS pathogenesis.

Introducing Evidence-Based Medicine and guidelines for maternal and newborn care in the Republic of Moldova

Familiarity with Evidence-Based Medicine (EBM) concepts is low amongst key maternal and newborn care clinicians in Moldova. Simple interventions can increase the knowledge of EBM concepts there.

Responsiveness to life-threatening obstetric emergencies in two hospitals in Abidjan, Cote d'Ivoire

OBJECTIVES

To document the frequency of severe obstetric illness, and the intervals between admission or decision and life-saving surgery and the factors contributing to delays, which were reported during case reviews in two hospitals in Abidjan, Côte d'Ivoire.

METHODS

The study was conducted in the teaching hospital in Cocody (CHUC) and the district hospital in Abobo (FSAS) in 2000-01. All severe obstetric cases were inventoried over a period of 1 year, and a subset of cases selected for in-depth review. For the 23 audited cases requiring emergency surgery, the interval between admission/decision and surgery was determined and reasons for the delays examined.

FINDINGS

The yearly incidence of severe obstetric morbidity was 224.5 and 11.8 per 1000 live births in the CHUC and FSAS respectively. In CHUC, the decision-to-delivery time was extremely long (median 4.8 h) and this was largely determined by the time needed to obtain a complete surgical kit (median 2.8 h), either because the family had to pay for it in advance or because the kit lacked some essential components, which had to be bought separately. In FSAS, the decision-to-delivery time was much shorter (median 1.0 h).

CONCLUSION

The interval between decision and emergency obstetric surgery substantially exceeded the 30 min generally advocated in industrialized countries. The reasons for the long delays were multiple and complex, but the main factors governing them were the huge case load of severe cases and the absence of any clear policy towards ensuring prompt and adequate treatment for life-threatening emergencies. In-depth reviews of cases of severe obstetric morbidity focusing in particular on the timing of emergency treatment could increase the responsiveness of the health system and providers to the needs of women requiring emergency obstetric care.

Chronic blockade of glutamate receptors enhances presynaptic release and downregulates the interaction between synaptophysin-synaptobrevin-vesicle-associated membrane protein 2

During development of neuronal circuits, presynaptic and postsynaptic functions are adjusted in concert, to optimize interneuronal signaling. We have investigated whether activation of glutamate receptors affects presynaptic function during synapse formation, when constitutive synaptic vesicle recycling is downregulated. Using primary cultures of hippocampal neurons as a model system, we have found that chronic exposure to both NMDA and non-NMDA glutamate receptor blockers during synaptogenesis produces an increase in miniature EPSC (mEPSC) frequency, with no significant changes in mEPSC amplitude or in the number of synapses. Enhanced synaptic vesicle recycling, selectively in glutamatergic nerve terminals, was confirmed by the increased uptake of antibodies directed against the lumenal domain of synaptotagmin. No increased uptake was detected in neuronal cultures grown in the chronic presence of TTX, speaking against an indirect effect caused by decreased electrical activity. Enhanced mEPSC frequency correlated with a reduction of synaptophysin-synaptobrevin-vesicle-associated membrane protein 2 (VAMP2) complexes detectable by immunoprecipitation. Intracellular perfusion with a peptide that inhibits the binding of synaptophysin to synaptobrevin-VAMP2 induced a remarkable increase of mEPSC frequency in control but not in glutamate receptor blocker-treated neurons. These findings suggest that activation of glutamate receptors plays a role in the downregulation of the basal rate of synaptic vesicle recycling that accompanies synapse formation. They also suggest that one of the mechanisms through which this downregulation is achieved is an increased interaction of synaptophysin with synaptobrevin-VAMP2.

Risk factors in Mozambican women with eclampsia: a case-referent study

In Maputo 133 consecutive eclamptic patients were compared with 393 non-eclamptic referent women. Significant risk factors for eclampsia were age < or = 18 years, household size < or = 3 individuals, unwanted pregnancy, walking to antenatal clinics and, in the thrid trimester, headache, foot oedema, hand or face oedema, epigastric pain, visual disturbance, ear buzzing and dizziness. Significantly more cases than referents reported no blood pressure measurements in antenatal clinics. It is concluded that the quality of antenatal clinics can be improved by enhanced community awareness of danger signs, by early recognition of risk factors and by better management of prodromal symptoms of eclampsia.

Defective antifungal T-helper 1 (TH1) immunity in a murine model of allogeneic T-cell-depleted bone marrow transplantation and its restoration by treatment with TH2 cytokine antagonists

Patients undergoing full haplotype-mismatched hematopoietic transplantations may experience severe intractable invasive fungal infections. To verify whether an imbalanced production of T-helper 1 (TH1) and TH2 cytokines may be responsible for susceptibility to fungal infections, C3H/HeJ (H-2(k)) recipient mice were lethally irradiated, received transplantations with T-cell-depleted allogeneic bone marrow (BM) cells from mice of H-2(d) haplotype, and were infected with Candida albicans. At different time-points after transplantation, mice were assessed for pattern of TH cytokine production and susceptibility to infection. The results show that a long-term, donor-type chimerism was achieved as early as 2 weeks after BM transplantation (BMT), at the time when high-level production of TH2 cytokines (interleukin-4 [IL-4] and IL-10) and impaired production of TH1 cytokines (interferon-gamma [IFN-gamma] and IL-12] were observed. At this time, mice were highly susceptible to both disseminated and mucosal infections, as indicated by decreased survival, uncontrolled fungal growth, and failure to develop protective TH1 immunity. However, a predominant production of TH1 cytokines was observed by week 5 after BMT, at the time when mice developed donor-type protective TH1 responses and were resistant to infections. Therapeutic ablation of IL-4 or IL-10 greatly increased resistance to candidiasis. These results indicate that a dysregulated production of TH cytokines occurs in mice undergoing T-cell-depleted allogeneic BMT. The transient predominant production of TH2 cytokines over that of IL-12 impaired the ability of mice to develop antifungal TH1 resistance, an activity that could be efficiently restored upon treatment with TH2 cytokine antagonists.

Different localizations and functions of L-type and N-type calcium channels during development of hippocampal neurons

Using immunocytochemical assays and patch-clamp and calcium-imaging recordings, we demonstrate that L-type and N-type calcium channels have distinct patterns of expression and distribution and play different functional roles during hippocampal neuron differentiation. L-type channels, which support the depolarization-induced calcium influx in neurons from the very early developmental stages, are functionally restricted to the somatodendritic compartment throughout neuronal development and play a crucial role in supporting neurite outgrowth at early developmental stages. N-type channels, which start contributing at later neuronal differentiation stages (3-4 DIV), are also functionally expressed in the axons of immature neurons. At this developmental stage preceding synaptogenesis, N-type (but not L-type) channels are involved in controlling synaptic vesicle recycling. It is only at later developmental stages (10-12 DIV), when the neurons have established a clear axodendritic polarity and form synaptic contacts, that N-type channels are progressively excluded from the axon. Electrophysiological recordings of single neurons growing in microislands revealed that synaptic maturation coincides with a progressive increase in N-type channels in the somatodendritic region and a progressive decrease in the N-type channels supporting glutamate release from the presynaptic terminal. These results indicate that L-type and N-type calcium channels undergo dynamic, developmentally regulated rearrangements in regional distribution and function and also suggest that different mechanisms may be involved in the sorting and/or stabilization of these two types of channels in different plasma membrane domains during neuronal differentiation.

Cytokines in candidiasis and aspergillosis

Both innate and T helper (Th) immunity play a central role in fungal infections. A bi-directional influence exists between the two compartments of the immune system, mainly occurring through cytokine production. On the one hand, protective Th1 or nonprotective Th2 cells mediate resistance or susceptibility to disseminated and localized fungal infections by secreting cytokines with activating or deactivating signals for effector phagocytic cells. On the other hand, cells of the innate immune system regulate the development of antifungal T helper responses by producing directive cytokines, such as interleukin (IL)-12 and IL-10. In experimental models of Candida albicans and Aspergillus fumigatus infections, the administration or neutralization of selective cytokines and the use of cytokine-deficient mice have revealed the existence of a hierarchical pattern of cytokine mediated regulation of antifungal Th cell development and effector function. A finely regulated balance of directive cytokines, rather than the relative absence of opposing cytokines, appears to be required for optimal development and maintenance of protective Th1 reactivity to fungi. Thus, it is conceivable that some cytokines may have beneficial or deleterious effects on infection, depending on the dose and timing of endogenous production or exogenous administration. A better understanding of the different, sometimes unexpected, roles of cytokines is required for their use in prophylaxis and therapy of fungal infections, either alone or in combination with antifungal agents.

Interleukin 18 restores defective Th1 immunity to Candida albicans in caspase 1-deficient mice

Caspase 1, formerly designated interleukin 1beta (IL-1beta)-converting enzyme, processes pro-IL-1beta and pro-IL-18 to yield active cytokines that play a pivotal role in inflammation and cell activation. We show here the effect of caspase 1 deficiency on the inflammatory and adaptive immune responses to the fungus Candida albicans. Caspase 1 deficiency did not affect susceptibility to primary systemic infection with the fungus, as revealed by survival and fungal growth. However, Th1-mediated resistance to reinfection was greatly impaired in caspase 1-deficient mice, and this correlated with low-level production of IL-12 and gamma interferon. Early in infection, production of these cytokines and that of tumor necrosis factor alpha, IL-6, and, interestingly, IL-1beta occurred normally in caspase 1-deficient mice, while that of IL-18 was severely impaired. Exogenous administration of IL-18, more than IL-12, restored the Th1-mediated resistance to the infection. We conclude that, while caspase 1 is not indispensable for release of mature IL-1beta in candidiasis, the caspase 1-dependent production of IL-18 may represent an important and novel pathway for the expression of sustained Th1 reactivity to the fungus.

T cell vaccination in mice with invasive pulmonary aspergillosis

Aspergillus fumigatus, an opportunistic fungal pathogen, is responsible for multiple airway diseases of an allergic and a nonallergic nature. In a murine model of invasive pulmonary aspergillosis, resistance is associated with a decreased lung inflammatory pathology and the occurrence of an IL-12-dependent Th1-type reactivity that are both impaired by IL-4. In the present study we assess the ability of Aspergillus crude culture filtrate Ags and the recombinant allergen Asp f 2 to induce protective antifungal responses in mice with invasive pulmonary aspergillosis. Similar to what occurred upon nasal exposure to viable A. fumigatus conidia, treatment of immunocompetent mice with Aspergillus crude culture filtrate Ags resulted in the development of local and peripheral protective Th1 memory responses, mediated by Ag-specific CD4+ T cells producing IFN-gamma and IL-2 capable of conferring protection upon adoptive transfer to naive recipients. Protective Th1 responses could not be observed in mice deficient of IFN-gamma or IL-12 and did not occur in response to Asp f 2, which, on the contrary, elicited high level production of inhibitory IL-4. The results show that Ags of Aspergillus exist with the ability to induce both Th1- and Th2-type reactivity during infection, a finding that suggests a possible mechanism through which potentially protective immune responses are inhibited in mice with the infection. However, the occurrence of Th1-mediated resistance upon vaccination with Aspergillus crude culture filtrate Ags, suggests the existence of fungal Ags useful as a candidate vaccine against invasive pulmonary aspergillosis.

Host immune reactivity determines the efficacy of combination immunotherapy and antifungal chemotherapy in candidiasis

In immunocompetent mice with candidiasis, successful therapy with amphotericin B and fluconazole relies on the induction of protective, T helper (Th) type 1 responses, an effect potentiated by concomitant interleukin (IL)-4 neutralization. To assess the therapeutic efficacy of combined treatments with antifungals and immunomodulators in conditions of immunosuppression, leukopenic or neutropenic mice with disseminated candidiasis were treated with amphotericin B or fluconazole alone or in combination with soluble IL-4 receptor (sIL-4R) or recombinant (r) IL-12 or IL-10 neutralizing monoclonal antibodies. We found that (1) the synergistic effect of sIL-4R and antifungals is retained in immunocompromised mice; (2) synergism with amphotericin B was superior to that with fluconazole, particularly in leukopenic mice; (3) rIL-12 synergized with fluconazole in neutropenic mice; and (4) IL-10 neutralization was always of limited efficacy. This study indicates that the therapeutic efficacy of antifungals is differentially potentiated by cytokines or cytokine antagonists and is influenced by host immune reactivity.

Antifungal type 1 responses are upregulated in IL-10-deficient mice

C57BL/6 mice are highly resistant to infections caused by Candida albicans and Aspergillus fumigatus. To elucidate the role of IL-10 produced by C57BL/6 mice during these infections, parameters of infection and immunity to it were evaluated in IL-10-deficient and wild-type mice with disseminated or gastrointestinal candidiasis or invasive pulmonary aspergillosis. Unlike parasitic protozoan infection, C. albicans or A. fumigatus infection did not induce significant acute toxicity in IL-10-deficient mice, who, instead, showed reduced fungal burden and fungal-associated inflammatory responses. The increased resistance to infections as compared to wild-type mice was associated with upregulation of innate and acquired antifungal Th1 responses, such as a dramatically higher production of IL-12, nitric oxide (NO) and TNF-alpha as well as IFN-gamma by CD4+ T cells. Pharmacological inhibition of NO production greatly reduced resistance to gastrointestinal candidiasis, thus pointing to the importance of IL-10-dependent NO regulation at mucosal sites in fungal infections. These results are reminiscent of those obtained in genetically susceptible mice, in which IL-10 administration increased, and IL-10 neutralization decreased, susceptibility to C. albicans and A. fumigatus infections. Collectively, these observations indicate that the absence of IL-10 augments innate and acquired antifungal immunity by upregulating type 1 cytokine responses. The resulting protective Th1 responses lead to a prompt reduction of fungal growth, thus preventing tissue destruction and lethal levels of proinflammatory cytokines.