[Endotoxin adsortion as adjuvant therapy in gram negative severe sepsis]

The mortality rate of severe sepsis and septic shock remains still high. Within the last years a better knowledge of its physiopathology and the implementation of a group of measures addressed to a fast identification and early treatment of the septic patients have proved to reduce mortality rate. Likewise, it continues being investigated in modulating the inflammatory response and limiting the harmful action of the bacterial products on the immune system. As a result of this research some endotoxin adsorber devices have been designed to control one of the most important targets that start the inflammatory cascade when gram negative microorganisms are involved.The usefulness that these endotoxin removal devices might have as adjuvant treatment in the Septic Syndrome and its applicability are reviewed in this paper. Likewise a profile of patient that might be to the benefit of this therapy is suggested according to the current knowledge.

[Recommendations in the empiric anti-infective agents of intra-abdominal infection]

A significant number of patients with abdominal infection develop advanced stages of infection and mortality is still above 20%. Failure is multifactorial and is associated with an increase of bacterial resistance, inappropriate empirical treatment, a higher comorbidity of patients and poor source control of infection. These guidelines discuss each of these problems and propose measures to avoid the failure based on the best current scientific evidence.

[Cognitive evoked potentials in remitting-relapsing and benign forms of multiple sclerosis]

INTRODUCTION

The assessment of the cognitive impairment in the multiple sclerosis disease is one of the most relevant challenges nowadays. An essential objective is to obtain diverse approaches that allow valuing objectively this impairment and its correlation with physiological variables.

AIM

To analyze the possible modulations in physiological components of the information processing (ERPs) related with an attentional deficit in diverse classes of patients with multiple sclerosis.

SUBJECTS AND METHODS

17 patients with remitting-relapsing multiple sclerosis, 9 patients with benign multiple sclerosis and 19 healthy subjects participated in the study. Behavioral performance in a visuo-spatial task (Posner paradigm) and later, an auditory oddball test was carried out where electroencephalography signal was registered to obtain ERPs. Correlation analyses were calculated between patient variables (EDSS or disease duration) and psychophysiological variables.

RESULTS

A delay in the reaction time during the development of the Posner task and a delay in the latency of the component P3 during the realization of the oddball task were found in both groups of patient with multiple sclerosis.

CONCLUSION

The data obtained in this experiment confirm the presence of attentional impairment in patients with diverse forms of multiple sclerosis. The exclusive modulation of the P3 latency component suggests that the impairment in these patients, at the beginning of the disease, is localized at a central level of cognitive processing and is product of the demyelinating process.

Constitutive expression of Bcl-2 in the haematopoietic compartment alters the metabolism of iron and increases resistance to mycobacterial infection

Mice expressing a vav-bcl-2 transgene were tested for their resistance to an experimental infection with Mycobacterium avium. When compared with control littermates, transgenic mice exhibited an increase in the resistance to infection which was independent of B or T lymphocytes and did not require the production of gamma interferon. Macrophages from both control and transgenic mice showed equal permissiveness to M. avium growth in vitro. Finally, transgenic mice expressed diminished circulating iron levels which correlated with the increased resistance to infection.

[Guidelines for the treatment on infections caused by methicillin-resistant Staphylococcus aureus]

Infections due to methicillin-resistant Staphylococcus aureus (MRSA) have undergone important changes in the last five years that have influenced the choice of therapy: i) increase of their frequency in hospital-associated settings and, more recently, in community settings; ii) better knowledge of clinical implications of the pharmacokinetic and pharmacodynamic properties of vancomycin; iii) improvement of current standard methods for rapid detection of MRSA in clinical samples; iv) clear evidence that vancomycin is losing efficacy against MRSA with MIC > 1 microg/mL; and v) appearance of new antibiotics suitable for use in these infections (linezolid, daptomycin, tigecyclin). Under this situation guidelines for the treatment of common infections caused by MRSA appear to be necessary to improve the efficacy and reduce the mortality.

Abnormal ERPs and high frequency bands power in multiple sclerosis

Event-related potentials (ERPs) and power spectral density (PSD) were registered during an auditory-oddball paradigm in 11 MS patients. These patients showed a decrease in the amplitude of P2 and N2 components and a delayed P3 latency compared to control subjects suggesting that the attentional orienting mechanism in the auditory modality is affected in MS. The PSD analysis showed that MS patients exhibited an increased power in beta and gamma bands. The combined analysis of frequency and time domain suggested diverse phenomena that occurred in the MS patient group related with the EEG background or the motivational status.

Bioequivalence of abacavir generic and innovator formulations under fasting and fed conditions

OBJECTIVE

Abacavir sulfate is a synthetic carbocyclic nucleoside analogue indicated for the treatment of HIV-1 infection in combination with other antiretroviral agents. The objective of the current study was to determine the bioequivalence between a generic formulation of abacavir and the innovator product.

MATERIAL AND METHODS

A total of 80 subjects were randomly assigned to receive a single 300 mg oral dose of abacavir sulfate as the generic (Ranbaxy-Abacavir, Ranbaxy Laboratories Ltd., equivalent to 300 mg of abacavir) and innovator (Ziagen, GlaxoSmithKline) tablet formulations in 2-way crossover studies performed under fasting (n=40) and fed (n=40) conditions. Multiple blood samples were collected over 14 hours and plasma concentrations of abacavir were assayed using an LC/MS/MS method with a limit of quantitation of 25.0 ng/ml. Pharmacokinetic (PK) parameters were calculated using noncompartmental methods.

RESULTS

Under fasting conditions, geometric mean area under the curve from time 0 to the last measurable concentration (AUC(0-t)), area under the curve extrapolated to infinity (AUC(0-infinity) and maximum plasma concentrations (Cmax) of abacavir for the generic (5565 ng x h/ml, 5668 ng x h/ml and 2526 ng/ml, respectively) and innovator (5675 ng x h/ml, 5770 ng x h/ml and 2528 ng/ml, respectively) products were very similar. Under fed conditions, mean values of AUC(0-t) AUC(0-infinity) and Cmax for the generic (4487 ng x h/ml, 4571 ng x h/ml and 1841 ng/ml, respectively) and innovator (4574 ng x h/ml, 4654 ng x h/ml and 1781 ng/ml, respectively) formulations were also very similar. Ratios of LSM and 90% confidence intervals of PK parameters between the 2 formulations were within 80.0 - 125.0% under fasting and fed conditions, suggesting that the 2 tablet formulations resulted in similar rate and extent of bioavailability. Adverse events for the generic and innovator products were similar in nature and frequency in the fasting and fed studies. CONCLUSIONS Based on the above results, the generic tablet formulation of abacavir developed by Ranbaxy should be equally effective as the innovator product.

Recent transmission of tuberculosis involving retired patients

The reported incidence of tuberculosis (TB) in three different regions of Rio Grande do Sul State in Brazil varies considerably. We used IS6110-RFLP and spoligotyping methods to genotype Mycobacterium tuberculosis isolates obtained from 268 patients between 1998 and 2000 in order to assess the levels of recent transmission of TB in the three regions. The degree of clustering of the strain types did not differ among the three regions; neither did other characteristics such as demographic features, underlying medical conditions, or the proportion of resistant TB. As reported previously, male patients were at greater risk of developing TB and our data suggest that part of this may be related to the higher rates of recent transmission among them (P<0.05). In addition, we found that retired patients were almost 3 times more likely to be infected with cluster-pattern strains than patients reporting any other occupation (P<0.05), and more than 3 times more likely than non-retired patients in the same age group (P<0.05) to be infected with cluster-pattern strains. We conclude that recent transmission is not a major factor contributing to the differences in TB incidence in the three regions of Rio Grande do Sul. The reason for the suggested high proportion of recent transmission TB cases among the retired people needs further studies.

Conversion of Trypanosoma cruzi Tc52 released factor to a protein inducing apoptosis

In this study Tc52, a Trypanosoma cruzi released protein, which exerts an immunoregulatory activity, was converted to a molecular form with altered biological function. Indeed, the genetic fusion of Tc52 to a carrier protein, the Shistosoma japonicum glutathione S-transferase (Tc52-Sj26), was shown to induce apoptosis in spleen cells from BALB/c or CBA mice and the human T-cell leukemic cell line (CEM). Cell death by apoptosis was evidenced by the following criteria: (1) increased binding of Annexin V to rTc52-treated spleen cells; (2) the presence of an ordered cleavage of the DNA backbone; (3) double labeling showed increased number of T cells undergoing apoptosis upon incubation with rTc52; (4) the use of a CEM cell line and TUNEL assay allowed to show in situ DNA fragmentation. Surprisingly, intraperitoneal injections of rTc52 to BALB/c mice, which were then infected with T. cruzi, resulted in increased parasiteamia levels and is congruent to 2.5 times increase of macrophages number. Since native Tc52 could not trigger, apoptosis of T cells we could hypothesized that the fusion of Tc52 with Sj26 led to conformational changes resulting in apoptosis inducing properties of rTc52. The possible in vivo physiopathological implications of these finding were discussed.

A two-colour fluorescence assay for the measurement of syncytial fusion between trophoblast-derived cell lines

Syncytial fusion is a key event in implantation and placentation. Its regulation is only poorly understood. We present a cell-cell fusion assay based on staining of cells in two portions with a green and a red fluorescent cytoplasmic dye that become intracellularly mixed only after syncytial fusion. We quantified cell-cell fusion by fluorescence microscopy in choriocarcinoma cell lines BeWo, JAR and JEG3 and in some non-trophoblastic cell lines and found clear differences in fusion behaviour. Only BeWo cells fused with each other, while the other cell lines tested did not. BeWo cells also fused with all other cell lines tested. The efficiency of cell-cell fusion of BeWo cells was stimulated by forskolin. We tried to correlate messenger levels of syncytin and its receptor RDR with the fusion index of choriocarcinoma cells. BeWo and JAR cells contained readily detectable and forskolin-inducible levels of syncytin mRNA, whereas this messenger was barely detectable in JEG3 cells. RDR transcript levels were similar in all cell lines tested and were unaffected by forskolin treatment. The data suggests that the expression of syncytin and RDR messengers alone does not guarantee successful fusion. The fusion assay presented in this paper is a useful tool to study syncytial fusion in an accurate and quantitative way.

Familial combined pituitary hormone deficiency due to a novel mutation R99Q in the hot spot region of Prophet of Pit-1 presenting as constitutional growth delay

Combined pituitary hormone deficiency (CPHD) is characterized by impaired production of GH and one or more of the other anterior pituitary hormones. Prophet of Pit-1 (PROP-1), one of the pituitary specific homeodomain transcription factors, is involved in the differentiation of the anterior pituitary cells (somatotrophs, lactotrophs, thyrotrophs, and gonadotrophs), and PROP-1 gene mutations may interfere with the development of these cells, resulting in CPHD. We performed molecular analyses of the PROP-1 gene in two siblings, born to consanguineous parents, who presented with short stature. The index patient, a boy, was initially diagnosed with constitutional growth delay based on familial short stature, low parental target height, normal GH secretion, and imaging of the pituitary gland. On follow-up, auxological data and pubertal delay prompted a thorough reevaluation, which documented GH, TSH, and gonadotropin deficiencies. Direct sequencing of the PROP-1 gene revealed a novel homozygous transition 296G-->A in exon 2 in the two affected siblings. The mutation substitutes a highly conserved arginine by a glutamine at codon 99 (R99Q) in the second helix of the DNA-binding domain of the PROP-1 protein. Compared with wild-type PROP-1, R99Q displays a significant decrease in DNA binding on a paired box response element (PRDQ9) and trans-activation of a luciferase reporter gene. The findings emphasize the importance of repeated evaluations and illustrate that patients with CPHD associated with PROP-1 mutations present with a phenotypic spectrum, suggesting that the consequences of distinct PROP-1 mutations may be diverse and/or that additional factors, such as modifier genes, may have an impact on their expressivity.

[Neuropsychological disorders in amyotrophic lateral sclerosis. Don't they exist or do they just go undetected?]

AIMS

The aims of this paper is to demonstrate the existence of neuropsychological disorders in amyotrophic lateral sclerosis (ALS) and to perform an in depth study of the cognitive functioning of the prefrontal lobes.

PATIENTS AND METHODS

A neuropsychological study of 14 patients with ALS was conducted using an extensive battery of tests and were compared with a group of 14 healthy controls. Both groups were homogeneous as regards age, sex, education and manual dominance. In this clinical and research study, as well as the neuropsychological variables (subtest of the Barcelona PIEN Test neuropsychological battery), we also took the evolution of the disease, the age and neurological clinical features of the patients suffering from ALS into account.

RESULTS

We found neuropsychological disorders in the ALS patients that were centred, either directly or indirectly, on functions of the prefrontal lobe, and in particular of the dorsolateral and premotor cortices, which had already been observed in other research work. No memory disorders were found, something which is usually mentioned in studies about neuropsychological disorders in this type of patients.

CONCLUSIONS

Apart from the primary motor zones affected in ALS, there appears to be a degenerative process in most of the frontal lobe, and there is a need for longitudinal studies of the possible progressive disorders of the frontal lobe in these patients. This is difficult, since these patients end up with serious neurological alterations which prevent a correct neuropsychological exploration from being carried out cognitively, and hence no conclusions can be drawn either

Identification and molecular characterization of two novel Trypanosoma cruzi genes encoding polypeptides sharing sequence motifs found in proteins involved in RNA editing reactions

We have previously identified a Trypanosoma cruzi cDNA encoding a protein named Tc52 sharing structural and functional properties with the thioredoxin and glutaredoxin protein family involved in thiol-disulphide redox reactions. Furthermore, we reported that Tc52 also plays a role in T. cruzi-associated immunosuppression observed during Chagas' disease. Moreover, Tc52 gene targeting deletion strategy allowed us to demonstrate that monoallelic disruption of Tc52 resulted in the alteration of the metacyclogenesis process and the production of less virulent parasites. Sequence analysis of a 7358 bp genomic fragment containing the Tc52 encoding gene revealed two additional open reading frames (ORF-A and C). The ORFs are likely to have protein coding function by a number of criteria, including reverse transcriptase polymerase chain reaction (RT-PCR), Western blot and immunofluorescence analyses. The deduced amino-acid (aa) sequence of the ORF-A localized upstream of the Tc52 gene revealed that it contains within its N-terminus (aa 1 to 170) four RGG boxes known to act as RNA binding motifs in some proteins that interact with RNA, interspersed with a high density of glycine with regular spacing of tryptophan (WX(9-10)) in which X is often a glycine. Moreover, the C-terminal part of the ORF-C (aa 253-289) contains a motif that is strikingly similar (7-35% identity, 14-46% similarity over 28aa) to a short sequence (RNP1) comprising the consensus sequence RNA binding domain (CS-RBD) found in a number of proteins that interact with RNA. The aa sequence from the ORF-C localized downstream of the Tc52 gene showed significant homology to human adenosine deaminase acting on RNA (hADAT1) that specifically deaminates adenosine 37 to inosine in eukaryotic tRNA(Ala) and to its homologue yeast protein (Tad1p) (22-25% identity and an additional 38-40% similarity over 177aa). Moreover, highly similar motifs of the deaminase domain are present in the T. cruzi ORF-C. Furthermore, the 5' flanking regions of the genes contained repeat TATA and CAAT nucleotide sequences which resemble the motifs found upstream of the transcription initiation sites in eukaryotic promoters. Therefore, the characterization of novel T. cruzi genes encoding proteins which show similarity to components of RNA processing reactions provides new tools to investigate the gene expression regulation in these parasitic organisms. Moreover, our recent findings on the Tc52 encoding gene underline the interest of genetic manipulation of T. cruzi, not only making it possible to use more closely an in vitro approach to find out how genes function, but also to obtain 'attenuated' strains that could be used in the development of vaccinal strategies.

Once weekly fluconazole is effective in children in the treatment of tinea capitis: a prospective, multicentre study

In an open, multicentre evaluation carried out in Brazil, Canada and South Africa we have demonstrated that fluconazole 8 mg kg-1 once weekly is effective in tinea capitis caused by Trichophyton and Microsporum species. There were 61 children, aged (mean +/- SE) 5.0 +/- 0.3 years; weight (mean +/- 5.6) 20.0 +/- 0.9 kg; 41 males, 20 females; one Asian, 57 Black, one Caucasian and two Hispanic. The organisms were Trichophyton violaceum (33 patients), T. tonsurans (11) and Microsporum canis (17). The extent of tinea capitis at pretherapy was: mild (18 patients), moderate (30) and severe (13). Patients with tinea capitis due to Trichophyton species were initially treated for 8 weeks with an extra 4 weeks of fluconazole if clinically indicated. All 44 patients with tinea capitis due to Trichophyton species were completely cured (clinically and mycologically) when evaluated 8 weeks after completion of active treatment, following 8 weeks of once weekly dosing in 35 patients and 12 weeks of once weekly dosing in nine patients. In Microsporum canis tinea capitis, an extra 4 weeks was administered at week 12 in patients where it was clinically indicated at the time. Sixteen of 17 patients with M. canis tinea capitis were completely cured (clinically and mycologically) when evaluated 8 weeks following the end of treatment when given for 8, 12 and 16 weeks in 12, one and three patients, respectively. Overall, complete cure (clinical and mycological) occurred in 60 of 61 patients at follow-up 8 weeks from the end of therapy. The duration of once weekly fluconazole in the 60 patients was 8 weeks (47 patients), 12 weeks (10 patients) and 16 weeks (three patients), respectively. Clinical adverse effects consisted of a mild, reversible gastrointestinal complaint in three (4.9%) of 61 children. A laboratory abnormality with elevated liver function tests was observed in one (5.9%) of 17 patients; this was asymptomatic, and reversible. No patient discontinued therapy. The data suggest that once weekly fluconazole dosing is effective, safe and associated with high compliance when used to treat tinea capitis.

PGP9.5 as a candidate tumor marker for non-small-cell lung cancer

PGP9.5 is a neurospecific peptide that functions to remove ubiquitin from ubiquitinated proteins and prevents them from targeted degradation by proteasomes. Using the serial analysis of gene expression method (SAGE), we observed that the PGP9.5 transcript was highly expressed in primary lung cancers and lung cancer cell lines but was not detectable in the normal lung. Here we examined the expression of PGP9.5 protein in normal lung epithelium, lung tumor cell lines, and 98 resected primary non-small-cell lung carcinomas (NSCLCs). We found PGP9.5 reactivity in normal lung in a pattern compatible with K-cells of the diffuse neuroendocrine system. However, the PGP9.5 was present in both small-cell lung cancer (SCLC) and NSCLC cell lines (22/24) independent of neuronal differentiation. In primary NSCLCs, 54% (53/98) of the cases had positive PGP9.5 staining, and the expression of protein was strongly associated with pathological stage of the cancer. It was present in 44% (29/66) of stage I NSCLCs and in 75% (24/32) of stage II and IIIA NSCLCs (p = 0.0032). These results suggest that the increased expression of PGP9.5 is specifically associated with lung cancer development and may serve as a potential marker for the detection of lung cancer.