Infection due to Aspergillus flavus and Rhizopus oryzae complex in a patient with diabetes mellitus

Fungal sinusitis is a pathology that can occur in patients with diabetes mellitus and be associated with a hyperglycemic crisis. It is an aggressive entity with local complications that include involvement of the orbit or the central nervous system, and vascular involvement. Despite surgical and antifungal treatment, mortality raises up to 75%. We report the case of a female patient with a diagnosis of diabetic ketoacidosis and signs of unilateral ophthalmoplegia, which led to the study with magnetic resonance imaging of the central nervous system, finding signs of sinusitis, meningitis, and cerebritis. Initial microbiological studies were negative, and biomarkers such as serum galactomannan and Cryptococcus antigen were also negative. After surgical management and the identification of Aspergillus flavus and Rhizopus spp. in sinus tissue, the patient received treatment with posaconazole and after two months of follow-up she presented clinical improvement. Dual fungal infection and infection by A. flavus are uncommon and clinically relevant entities, with no cases previously reported in our country, therefore this corresponds to a case of clinical interest.

Original articleAnalysis of the effectiveness and safety of short-stay units in the hospitalization of patients with acute heart failure. Propensity Score SSU-EAHFE

OBJECTIVES

This work aims to analyze if hospitalization in short-stay units (SSU) of patients diagnosed in the emergency department with acute heart failure (AHF) is effective in terms of the length of hospital stay and if it is associated with differences in short-term progress.

METHOD

Patients from the EAHFE registry diagnosed with AHF who were admitted to the SSU (SSU group) were included and compared to those hospitalized in other departments (non-SSU group) from all hospitals (comparison A) and, separately, those from hospitals with an SSU (comparison B) and without an SSU (comparison C). For each comparison, patients in the SSU/non-SSU groups were matched by propensity score. The length of hospital stay (efficacy), 30-day mortality, and post-discharge adverse events at 30 days (safety) were compared.

RESULTS

A total of 2,003 SSU patients and 12,193 non-SSU patients were identified. Of them, 674 pairs of patients were matched for comparison A, 634 for comparison B, and 588 for comparison C. The hospital stay was significantly shorter in the SSU group in all comparisons (A: median 4 days (IQR = 2-5) versus 8 (5-12) days, p < 0.001; B: 4 (2-5) versus 8 (5-12), p < 0.001; C: 4 (2-5) versus 8 (6-12), p < 0.001). Admission to the SSU was not associated with differences in mortality (A: HR = 1.027, 95%CI = 0.681-1.549; B: 0.976, 0.647-1.472; C: 0.818, 0.662-1.010) or post-discharge adverse events (A: HR = 1.002, 95%CI = 0.816-1.232; B: 0.983, 0.796-1.215; C: 1.135, 0.905-1.424).

CONCLUSION

The hospitalization of patients with AHF in the SSU is associated with shorter hospital stays but there were no differences in short-term progress.

[Pseudo-thrombotic microangiopathy due to vitamin B12 deficiency in an infant]

Pseudo-thrombotic microangiopathy, or Moschcowitz syndrome, is a rare manifestation of vitamin B12 deficiency. It is characterized by microangiopathic hemolytic anemia, reticulocytes, and hematimetric indices that can be normal or that might present a mild megaloblastosis, and which are associated with neurological manifestations. Vitamin B12 can be found in animal-based protein foods. Breastfeeding is an adequate source of this vitamin for children, when maternal serum levels are normal. The case of a 16-month-old infant is presented. She was admitted for hemolytic anemia with transfusion requirement, thrombocytopenia, failure to thrive and developmental delay. During her hospitalization, she was diagnosed with pseudothrombotic microangiopathy caused by vitamin B12 deficiency.

Influence of an external electric field on the rapid synthesis of MoO3 micro- and nanostructures by Joule heating of Mo wires

The growth mechanism of layered α-MoO₃ nano- and microplates on the surface of Mo wires during Joule heating has been investigated by application of an external electric field to the current carrying wire. The observed rapid growth of the structures, involving enhanced diffusion processes associated to the intense electric current, is further enhanced by the external field leading to a near instantaneous formation of MoO₃ plates. Thermally assisted electromigration in the Mo wire with the additional effect of the electric field appears as a very time effective method to grow MoO₃ layered low dimensional structures. Other molybdenum oxide nanostructures, such as nanospheres and nanocrystallites with different shapes, have been found to grow by deposition from the Mo wire on the electrodes used to apply the external electric field. The growth on the electrodes takes place by a thermally assisted electric-field-driven process.

Clinicopathological significance of miR-26, miR-107, miR-125b, and miR-203 in head and neck carcinomas

OBJECTIVES

MicroRNAs play a role in the development and progression of head and neck squamous cell carcinomas (HNSCC). Our aim was to study the expression of miR-26, miR-107, miR-125b, and miR-203 in primary HNSCC with and without lymph node metastasis and their clinicopathological significance.

MATERIALS AND METHODS

The expression of microRNAs in primary HNSCC with lymph node metastasis (n = 16) and their matched lymph node, as well as primary tumors without metastasis (n = 16), were determined by quantitative RT-PCR and analyzed with clinicopathological features and survival.

RESULTS

The expression levels of miR-26 (p < .05) and miR-125b (p < .01) were higher in metastatic primary HNSCC, while levels of miR-203 (p < .01) were lower. The expression of the microRNAs was associated with clinicopathological features, including miR-26 high expression and N stage (p = .04), poor differentiation (p = .005) and recurrence (p = .007), miR-125b high expression and N stage (p = .0005) and death (p = .02), and low levels of miR-203 and N stage (p = .04). The high expression of miR-26 was associated with shortened disease-free survival, and high miR-125b expression was an independent risk factor for poor disease-specific survival.

CONCLUSIONS

These findings suggest that miR-26 and miR-125b may be associated with the progression and metastasis of HNSCC and that miR-203 is associated with a more favorable prognosis.

Parameters of metabolic quantification in clinical practice. Is it now time to include them in reports?

Qualitative techniques have traditionally been the standard for the diagnostic assessment with ¹⁸F-FDG PET studies. Since the introduction of the technique, quantitative parameters have been sought, more accurate and with better diagnostic precision, that may offer relevant information of the behavior, aggressiveness or prognosis of tumors. Nowadays, more and more studies with high quality evidence show the utility of other metabolic parameters different from the SUV maximum, which despite being widely used in clinical practice is controversial and many physicians still do not know its real meaning. The objective of this paper has been to review the key concepts of these metabolic parameters that could be relevant in normal practice in the future. It has been seen that there is more evidence in the complete evaluation of the metabolism of a lesion, through volumetric parameters that more adequately reflect the patient's tumor burden. Basically, these parameters calculate the volume of tumor that fulfills certain characteristics. A software available in the majority of the workstations has been used for this purpose and it has allowed to calculate these volumes using more or less complex criteria. The simplest threshold-based segmentation methods are available in most equipments, they are easy to calculate and they have been shown in many studies to have an important prognostic significance.

Experimentally-Based Computational Investigation into Beat-To-Beat Variability in Ventricular Repolarization and Its Response to Ionic Current Inhibition

Beat-to-beat variability in repolarization (BVR) has been proposed as an arrhythmic risk marker for disease and pharmacological action. The mechanisms are unclear but BVR is thought to be a cell level manifestation of ion channel stochasticity, modulated by cell-to-cell differences in ionic conductances. In this study, we describe the construction of an experimentally-calibrated set of stochastic cardiac cell models that captures both BVR and cell-to-cell differences in BVR displayed in isolated canine action potential measurements using pharmacological agents. Simulated and experimental ranges of BVR are compared in control and under pharmacological inhibition, and the key ionic currents determining BVR under physiological and pharmacological conditions are identified. Results show that the 4-aminopyridine-sensitive transient outward potassium current, I_to1, is a fundamental driver of BVR in control and upon complete inhibition of the slow delayed rectifier potassium current, I_Ks. In contrast, I_Ks and the L-type calcium current, I_CaL, become the major contributors to BVR upon inhibition of the fast delayed rectifier potassium current, I_Kr. This highlights both I_Ks and I_to1 as key contributors to repolarization reserve. Partial correlation analysis identifies the distribution of I_to1 channel numbers as an important independent determinant of the magnitude of BVR and drug-induced change in BVR in control and under pharmacological inhibition of ionic currents. Distributions in the number of I_Ks and I_CaL channels only become independent determinants of the magnitude of BVR upon complete inhibition of I_Kr. These findings provide quantitative insights into the ionic causes of BVR as a marker for repolarization reserve, both under control condition and pharmacological inhibition.

Influence of TiO2 nanostructures on anti-adhesion and photoinduced bactericidal properties of thin film composite membranes

This work investigates the influence of TiO₂ nanostructures on the anti-adhesion and photoinduced bactericidal properties of thin film composite (TFC) membranes.

Lipid accumulation inRhodotorula glutinis on sugar cane molasses in single-stage continuous culture

Microbial lipids produced byRhodotorula glutinis grown in continuous culture with molasses under nitrogen-limiting conditions were evaluated and the effects of growth rate on fatty acid composition were studied. As the growth rate decreased, cell biomass, lipid content and lipid yield gradually increased. The maximum lipid content recorded was 39% (w/w) of dry cell biomass at a dilution rate of 0.04 h(-1). The growth rate also affected fatty acid composition: oleic acid decreased with decreasing growth rate while stearic acid increased.

Physiological response of high-level female judokas measured through laboratory and field tests. Retesting the validity of the Santos test

AIM

The aim of the study was to measure the physiological demands of a group of high-level female judokas through laboratory tests and field tests (Tatami) and to retest the validity of the Santos test on a different population.

METHODS

Eight high-level female judokas participated in the study. Heart rate (HR), maximal oxygen consumption (VO2 max), blood lactate, anaerobic threshold, and ratings of perceived exertion (RPE) were measured using laboratory and field tests that shared common characteristics.

RESULTS

The mean (±SD) values obtained in the laboratory tests were HRmax 198.3 (4.1) beats.min-1, VO2 max: 40.9 (7.7) mL.kg-1.min-1, lactate max 9.1 (1.4) mmol.L-1, HR at the anaerobic threshold 171.5 (4.8) beats.min-1, lactate threshold 3.8 (0.4) mmol.L-1, and RPE: 17 (1.1). The mean (±SD) values obtained in the field test were HRmax 199.0 (5.0) beats.min-1, VO2 max: 44.8 (7.3) mL.kg-1.min-1, lactate max: 11.8 (1.5) mmol.l-1, HR at the anaerobic threshold 170.5 (3.2) beats.min-1, lactate threshold: 3.8 (0.1) mmol.L-1, and RPE: 18 (1.4) points. There were no significant differences between the data obtained on both tests in any of the parameters, except for the lactate maximum and VO2 max.

CONCLUSION

The Santos test is a helpful instrument for judo training in female athletes. Coaches could use it to design specific training protocols that could help to improve their performance in competition.

Inability of recombinant human thyrotropin to predict the evolution from subclinical hypothyroidism to overt disease. A pilot study

BACKGROUND

The use of recombinant human TSH (rhTSH) is indicated to evaluate thyroid carcinoma patients. In recent years, some authors have reported that rhTSH could serve as a dynamic test of thyroid reserve. The aim of the present study was to determine whether or not rhTSH can predict the evolution from subclinical hypothyroidism (SH) to overt hypothyroidism.

MATERIALS AND METHODS

Twenty-one women who met the diagnostic criteria of SH were enrolled. All patients received a single dose of rhTSH (0.1 mg). Basal blood samples for TSH, free T4 (fT4), thyroglobulin (Tg), and anti-thyoperoxidase and anti-Tg antibodies were obtained before and 1 day after rhTSH administration. All patients were followed for 2 yr, and blood samples were obtained every 6 months.

RESULTS

Twenty-four hours after rhTSH administration, the TSH level increased to >20 mU/l in 14 patients; the serum peak TSH levels remained <10 mU/l in only 5 patients. On follow-up, 7 women (33%) required L-T4 replacement therapy for overt hypothyroidism or a persistent TSH level >10 mlU/l. None of the parameters analyzed differed significantly between patients who developed overt hypothyroidism from those who had persistent SH.

CONCLUSIONS

The response of thyroid function tests to a single low dose of rhTSH is not useful in identifying those patients with SH who will develop overt hypothyroidism over a 2-yr period.

Boerhaave's syndrome as the primary manifestation of adult eosinophilic esophagitis. Two case reports and a review of the literature

Eosinophilic esophagitis (EoE) has been associated with an increased risk of esophageal mucosal tears induced by vomiting to dislodge impacted food or following endoscopic procedures. However, Boerhaave's syndrome or transmural perforation of the organ resulting from vomiting induced to dislodge impacted food has rarely been reported. In this article, we present two male adult patients with long-term esophageal symptoms who suffered from Boerhaave's syndrome after the impaction of food in the esophagus. Both patients required surgical management because of clinical and radiological signs of perforation. This rare complication of EoE has been documented in 11 other reports, predominantly affecting young men in whom EoE had not been previously diagnosed, despite the majority having esophageal symptoms and a history of atopy. There are only two published cases of esophageal perforation that presented in children, which were managed conservatively. Our two patients and 4 out of the 11 described in literature required surgery because of esophageal perforation. Our two cases involved closure of the perforation, while in three published reports, perforation resulted in a partial or complete esophagectomy. No cases have been published on Boerhaave's syndrome caused by EoE that ended in fatalities. It is important to note that esophageal perforation caused by vomiting is a potentially severe complication of EoE that is being increasingly described in literature. Therefore, patients with non-traumatic Boerhaave's syndrome should be assessed for EoE, especially if they are young men who have a prior history of dysphagia and allergic manifestations.

Rapid and sensitive detection of African horse sickness virus by real-time PCR

A highly sensitive and specific TaqMan-MGB real-time RT-PCR assay has been developed and standardised for the detection of African horse sickness virus (AHSV). Primers and MGB probe specific for AHSV were selected within a highly conserved region of genome segment 7. The robustness and general application of the diagnostic method were verified by the detection of 12 AHSV isolates from all of the nine serotypes. The analytical sensitivity ranged from 0.001 to 0.15 TCID(50) per reaction, depending on the viral serotype. Real-time PCR performance was preliminarily assessed by analysing a panel of field equine samples. The same primer pair was used to standardise a conventional RT-PCR as an affordable, useful and simple alternative method in laboratories without access to real-time PCR instruments. The two techniques present novel tools to improve the molecular diagnosis of African horse sickness (AHS).

Kaurane diterpenes protect against apoptosis and inhibition of phagocytosis in activated macrophages

BACKGROUND AND PURPOSE

The kaurane diterpenes foliol and linearol are inhibitors of the activation of nuclear factor kappaB, a transcription factor involved in the inflammatory response. Effects of these diterpenes on apoptosis and phagocytosis have been analysed in cultured peritoneal macrophages and in the mouse macrophage cell line, RAW 264.7.

EXPERIMENTAL APPROACH

Macrophages were maintained in culture and activated with pro-inflammatory stimuli in the absence or presence of diterpenes. Apoptosis and the phagocytosis in these cells under these conditions were determined.

KEY RESULTS

Incubation of macrophages with a mixture of bacterial lipopolysaccharide (LPS)/interferon-gamma (IFN-gamma) induced apoptosis through a NO-dependent pathway, an effect significantly inhibited by foliol and linearol in the low muM range, without cytotoxic effects. Apoptosis in macrophages induced by NO donors was also inhibited. The diterpenes prevented apoptosis through a mechanism compatible with the inhibition of caspase-3 activation, release of cytochrome c to the cytosol and p53 overexpression, as well as an alteration in the levels of proteins of the Bcl-2 family, in particular, the levels of Bax. Cleavage of poly(ADP-ribose) polymerase, a well-established caspase substrate, was reduced by these diterpenes. Treatment of cells with foliol and linearol decreased phagocytosis of zymosan bioparticles by RAW 264.7 cells and to a greater extent by peritoneal macrophages.

CONCLUSIONS AND IMPLICATIONS

Both diterpenes protected macrophages from apoptosis and inhibited phagocytosis, resulting in a paradoxical control of macrophage function, as viability was prolonged but inflammatory and phagocytic functions were impaired.

Stem cell markers in gastrointestinal cancer

21095

Background: Cancer cells with stem cells (CSC) properties have been identified in different tumors. It is suggested that CSC are responsible for the continuous growth of tumors, metastasis and drug-resistance. Markers for stem cells have been described. Oct4 and Nanog are transcription factors required to maintain the pluripotency and self-renewal of embryonic stem (ES) cells. ABCG2 transporter (MDR1) gene expression has been described as surrogate for the side-population phenotype. PTTG1 has also been recently identified as a component of the molecular signature of human (hu) ES cell-lines. Methods: Using Digital Northern we have demonstrated a significant tag counts for PTTG1 and reticulocalbin 2 (RCN2) in 11 huES cell-lines of the CGAP. The objective of our work has been to assess gene expression of these SC markers in a panel of new gastrointestinal cancer (GC) cells lines (CL) developed in our laboratory. Quantitative assessment was obtained by real-time PCR relative to normal bone marrow (BM), colonic mucosa and established cell-lines. GCCLs have been developed from ascitic fluid obtained of pancreatic carcinoma (MBQ-OJC1) and colon cancer (JJPF-OJC4, LCM-OJC5 and JAC-OJC6). GCCLs had been fully characterized by cytomorphology, epithelial and tumor markers (keratins, EGFR, EpCAM, p53), karyotype and tumor spheroids cultures. Results: Expression for ABCG2, Nanog, Oct4, PTTG1 and RCN2 were clearly detected in all the GCCL. Relative levels for each mRNA shown wide variety. For example, ABCG2 mRNA was highly expressed (2–26 fold) in colon cancer CL relative to BM. RCN2 was overexpressed (more than 2 x 102 fold) in 3 GCCL. Conclusions: Our results show that expressions of different “stemness” genes are maintained in cultured cancer cells. These data suggest that CSC are present in metastatic sites and can be maintained in continuous culture. We hypothesized that PTTG1 and RCN2 could be tested as a new cancer stem cells markers.

No significant financial relationships to disclose.

Evaluation of ALOA plating medium for its suitability to recover high pressure-injured Listeria monocytogenes from ground chicken meat

AIMS

To evaluate a chromogenic plating medium for the isolation of sublethally injured cells of Listeria monocytogenes from processed foods.

METHODS AND RESULTS

The inactivation of L. monocytogenes at pressures up to 400 MPa and 12 degrees C in ground chicken meat was employed to examine the recovery of high-pressure injured cells. Before and after different repair incubation periods at 30 degrees C in a nonselective broth, samples were plated onto a selective and differential agar [Agar Listeria according to Ottaviani and Agosti (ALOA)] and in the same medium supplemented with 4% sodium chloride (ALOA-S), and incubated at 37 degrees C. Sublethally injured cells were able to grow when directly plated onto the ALOA medium, without a previous repair incubation period. However, only uninjured cells grew on the ALOA-S medium.

CONCLUSIONS

Sublethally injured cells of L. monocytogenes can be quantified by subtracting counts on ALOA-S medium from counts on ALOA medium.

SIGNIFICANCE AND IMPACT OF THE STUDY

Possible applications include direct enumeration on ALOA of stressed cells of L. monocytogenes in foods with more than 100 colony forming units per gram.

[Analysis of oxidative stress in exhaled breath condensate from patients with severe pulmonary infections]

OBJECTIVE

Oxidative stress is an intrinsic part of the chain of events leading to inflammation of the airways caused by bacterial infection. The aim of this study was to determine whether analysis of exhaled breath condensate from patients with severe lung infections reveals changes in the redox state at the airway surface.

PATIENTS AND METHODS

The study included a total of 48 subjects divided into 4 groups: individuals without respiratory disease (n=14), patients with multilobar pneumonia (n=13), patients who had chronic obstructive pulmonary disease with superinfection (n=14), and mechanically ventilated patients with severe pneumonia (n=7). A sample of exhaled breath condensate was obtained within the first 72 hours of hospital admission and the concentrations of nitrite, nitrate, 8-isoprostane, and myeloperoxidase (MPO) were determined.

RESULTS

Significant differences in the concentrations of nitrite, 8-isoprostane, and MPO were observed between patients and individuals without respiratory disease but no differences were found between the 3 patient groups. The concentration of MPO was correlated with the concentrations of 8-isoprostane and nitrate, which were normalized to the nitrite concentration.

CONCLUSIONS

Analysis of the concentrations of 8-isoprostane and MPO in exhaled breath condensate allows assessment of oxidative stress in the airways of patients with severe lung infections.

Effects of dietary L-arginine supplementation on serum lipids and intestinal enzyme activities in diabetic rats

We investigated whether dietary supplementation with L-arginine, the endogenous precursor of nitric oxide, might affect serum lipid levels and activities of intestinal mucosa enzymes in animals, in which diabetes was induced by administration of streptozotocin. Control and diabetic rats were fed diets with or without 2% L-arginine supplementation for 4 weeks. Diabetic rats had significantly higher concentrations of serum triglycerides and LDL-cholesterol than control rats. These alterations were partially reduced by L-arginine supplementation. Experimental diabetes did not influence the lactase and leucine aminopeptidase activity in the intestine, but the activity of alkaline phosphatase was increased. Furthermore, activities of maltase and sucrase in the intestinal mucosa were elevated in streptozotocin-induced diabetic rats and were restored to control levels after dietary L-arginine supplementation. On the basis of the present experimental evidence, dietary L-arginine supplementation appears to affect the metabolism of lipoproteins and might alleviate some gastrointestinal dysfunctions, commonly seen in diabetes mellitus.

Terpenoids: sources, structure elucidation and therapeutic potential in inflammation

Natural products research has lately undergone exponential growth owing to advances in isolation techniques and in synthetic methods design, as well as for the identification of a wide range of biological properties exhibited by these compounds. In the present review, general remarks on the chemical features, biosynthetic pathways, isolation and structure elucidation of terpenoids are briefly discussed. In addition to this, recent work done on anti-inflammatory terpenoids (diterpenoids, triterpenoids and sesquiterpene lactones) with special emphasis on the last new molecular targets evaluated is presented.

Lower malfunction rate with self-locating catheters

OBJECTIVE

We analyzed malfunction rates (obstruction, omental wrapping, displacement) and catheter survival for self-locating catheters as compared with other Tenckhoff catheter designs.

PATIENTS AND METHODS

We conducted our survey at two centers, prospectively studying all self-locating catheters implanted from May 1997 to October 2000 and used for peritoneal dialysis (PD). Tenckhoff catheters of other designs used previously in our units were used as the control group. We analyzed removal causes and catheter survival.

RESULTS

We studied 173 catheters (105 self-locating catheters, 53 straight catheters, and 15 coiled catheters) implanted in 139 patients (43% of them women) with a mean age of 53 +/- 14 years. The analysis of catheter removal showed that 3 of 105 self-locating catheters, 3 of 15 coiled catheters, and 17 of 53 straight catheters were removed owing to malfunction (chi2: p = 0.0000). Kaplan-Meier curves showed that the bulk of removals for malfunction occurred within the first 3 months after PD start. The group of self-locating catheters showed better survival (log-rank: p = 0.0009). Other causes for catheter removal included peritonitis (n = 22), exit-site infection alone (n = 4), and end of PD treatment (n = 66). No significant differences were seen in the annual peritonitis rate (straight-tip: 0.955 +/- 2.315 episodes annually; coiled-tip: 0.651 +/- 0.864 episodes annually; self-locating: 0.720 +/- 1.417 episodes annually; t-test: p > 0.400). No gut or bladder perforations were observed.

CONCLUSION

In our survey, self-locating catheters were associated with better survival and fewer removals for malfunction than were Tenckhoff catheters of other designs.

Mechanistic investigation of extracellular K+ accumulation during acute myocardial ischemia: a simulation study

In this study, we have used computer simulations to study the mechanisms of extracellular K+ accumulation during acute ischemia. A modified version of the Luo-Rudy phase II action potential model was used to simulate the electrical behavior of one ventricular myocyte during 14 min of simulated ischemia. Our results show the following: 1) only the integrated effect of activation of ATP-dependent K+ current, an ischemic Na+ inward current, and inhibition of Na(+)-K(+) pump activity in the absence of coronary flow replicates the biphasic time course of extracellular K+ concentration observed during acute ischemia; 2) the time to onset of the plateau phase and the plateau level value are determined by the rate of stimulation and by the rate of alteration of the three mechanisms. However, acidosis and reduction of extracellular volume produce only a slight anticipation of the plateau phase; and 3) cellular K+ loss is mainly due to an increase of K+ efflux via the time-independent K+ current and ATP-dependent K+ current rather than to a decrease of K+ influx.

Effects of six diterpenes on macrophage eicosanoid biosynthesis

Six diterpenes (three clerodanes, two abietanes and one rosane) were tested for interactions with the cyclooxygenase and 5-lipoxygenase pathways of arachidonate metabolism and for effects of nitric oxide production. Two abietane diterpenes, aethiopinone and 11,12-dihydroxy-6-oxo-8,11,13-abietatriene and the rosane lagascatriol showed a remarkable effect on COX-1 pathway of PGE2 release in calcium ionophore A23187-stimulated peritoneal macrophages. Only the two latter diterpenes showed inhibition on COX-2 pathway of PGE2 release in E. coli LPS-stimulated peritoneal macrophages. In addition, all compounds assayed were inhibitors of LTC4 release with IC50 < or = 10 microM. Clerodane diterpenes were inactive in COX assay. None of the diterpenes assayed, except 11,12-dihydroxy-6-oxo-8,11,13-abietatriene, affected NO production. The results obtained suggest that the cellular mechanisms of action of some of these substances may involve inhibition of cyclooxygenase/lipoxygenase pathways and nitric oxide production.

Effects of ajugarins and related neoclerodane diterpenoids on feeding behaviour of Leptinotarsa decemlineata and Spodoptera exigua larvae

Three naturally occurring ajugarins and seven semisynthetic derivatives of them, possessing different functionalities in the decalin part, together with two natural furoneoclerodane diterpenes, have been assessed as feeding behavior modifying agents of larvae of the generalist Spodoptera exigua and a specialist like Leptinotarsa decemlineata. Ajugarin I and some of its derivatives exhibited a significant antifeedant activity against larvae of S. exigua in both choice and no-choice assays. Conversely, the furoneoclerodane diterpenes only presented antifeedant activity against larvae of L. decemlineata. These results indicate that the biological action of the tested substances is strongly modulated by minimal structural variations, which are also responsible for the specificity of action.

Diterpenoids from Acacia leucophloea: revision of the structures of leucophleol and leucophleoxol

The pimarane-type structures previously suggested for leucophleol (1) and leucophleoxol (2), two diterpenoids isolated from Acacia leucophloea, must be amended to the isopimarane-type derivatives 5 and 6, respectively. These corrections were supported on NMR spectroscopic studies and, in the case of 6, by an X-ray diffraction analysis. Moreover, the unpublished complete and unambiguous (1)H and (13)C NMR assignments of 5 and 6 together with those of leucoxol (3), another diterpenoid from the same plant, are also reported.

Presence of a major WFS1 mutation in Spanish Wolfram syndrome pedigrees

Wolfram syndrome (WS) is an autosomal recessive neurodegenerative disease mainly characterized by familial diabetes mellitus and optic atrophy. WS patients frequently present with other clinical features such as diabetes insipidus, renal abnormalities, psychiatric disorders, and a variety of neurologic symptoms: deafness, ataxia, peripheral neuropathy. A gene responsible for Wolfram Syndrome (WFS1) has been recently identified on chromosome 4p16.1. Twenty-two Wolfram patients from 16 Spanish families were screened for mutations in the WFS1 coding region by SSCP analysis and direct sequencing. Since WS has been considered a mitochondrial disorder for some time, mitochondrial DNA (mtDNA) in these families was also examined. WFS1 mutations were detected in 75% of families (12 of 16). One of these mutations, an insertion of 16 base pairs in exon 4, turned out to be notably frequent in Spanish pedigrees. As many as 50% of pedigrees with WFS1 mutations harbored this insertion, either in one (33% of cases) or in two chromosomes (67%). Ten other mutations were identified: 7 missense changes, 2 deletions, and 1 nonsense mutation. Only 3 of these changes had been previously described in non-Spanish pedigrees. Large mtDNA rearrangements and LHON point mutations were detected in four and six families, respectively. No correlation could be established between WFS1 gene mutations and specific point mutations or rearrangements in mtDNA. We would suggest first screening for the 16-bp insertion in exon 4 when a new Spanish WS case is reported.

Construction and characterization of a nonproliferative El Tor cholera vaccine candidate derived from strain 638

In recent clinical assays, our cholera vaccine candidate strain, Vibrio cholerae 638 El Tor Ogawa, was well tolerated and immunogenic in Cuban volunteers. In this work we describe the construction of 638T, a thymidine auxotrophic version of improved environmental biosafety. In so doing, the thyA gene from V. cholerae was cloned, sequenced, mutated in vitro, and used to replace the wild-type allele. Except for its dependence on thymidine for growth in minimal medium, 638T is essentially indistinguishable from 638 in the rate of growth and morphology in complete medium. The two strains showed equivalent phenotypes with regard to motility, expression of the celA marker, colonization capacity in the infant mouse cholera model, and immunogenicity in the adult rabbit cholera model. However, the ability of this new strain to survive environmental starvation was limited with respect to that of 638. Taken together, these results suggest that this live, attenuated, but nonproliferative strain is a new, promising cholera vaccine candidate.

[Obtention, characterization of antigens and evaluation of the immunotransfer technique for the detection of systemic candidiasis]

A culture media containing peptone, glucose, yeast extract and serum was evaluated to promote the development of the mycelium formation in Candida albicans and it was compared with the commercial media Tc 199. No significant difference was found between them. Somatic antigens characterized by PAGE-SDS were obtained from yeast and mycelial forms. Proteins reported as having high diagnostic value were expressed in both antigens. It was determined by immunotransference that the antigenic proteins predominating in the mycelium formation had molecular weights of 19, 21, 27 and 57 Kda. The immunotransference was standardized for detecting antibodies in patients with systemic candidiasis. 24 positive sera were evaluated by this technique and it was compared with the ELISA technique, which proved to be more sensitive and less specific. The most recognized proteins were those of 136 and 21 Kda and the complex from 42 to 45 Kda.

[Parasitic helminths from Sigmodon hispidus (Rodentia: Cricetidae) from seasonal and evergreen habitats in Costa Rica]

The helminthological fauna of the cotton rat, Sigmodon hispidus in a tropical environment varies according to habitat and feeding behavior. Six species of nematodes (Longistriata adunca, Trichostrongylus sigmodontis, Strongyloides sigmodontis, Litomosoides carinii, Monodontus sp. and Protospirura sp.) and two species of cestodes (Hymenolepis diminuta and Raillietina sp.) were found in rats from extensive dry lands in Guanacaste where hot temperatures and heterogeneous diet are the rule. Only two species of nematodes (Longistriata adunca and Angiostrongylus costaricensis) were found in rats collected in a humid pineapple plantation in the Central Plateau (Alajuela) where mild temperatures predominate. A. costaricensis, a metastrongylid of medical importance, was found in 42% of them.

Isopimarane diterpenoids from Lycopus europaeus

A reinvestigation of the diterpene metabolites of Lycopus europaeus allowed the isolation of five new compounds, namely, four isopimarane derivatives (1-4) and 5,9-dihydroxygeranyllinalool (5). The structures of these substances were established by chemical and spectroscopic means.

Absence of mitochondrial dysfunction in polymyalgia rheumatica. Evidence based on a simultaneous molecular and biochemical approach

OBJECTIVE

To investigate the molecular and biochemical profile of skeletal muscle mitochondria of patients with isolated polymyalgia rheumatica (PMR).

PATIENTS AND METHODS

We included patients with a recent diagnosis of PMR and as control healthy individuals submitted to orthopedic surgery. Skeletal muscle was obtained from quadriceps, thus was mitochondria immediately isolated. Long polymerase chain reaction and Southern blot transference were performed to detect deleted mtDNA molecules. Mitochondrial oxidative activity using different substrates and individual enzyme activity of respiratory chain complexes were assessed to search for any biochemical dysfunction.

RESULTS

Fifty-one individuals (PMR=25, controls=26) were included. Mean age was 72 (11) years; 45% were females. We found no significant increase of deleted mtDNA molecules in PMR patients compared to controls. Both groups differed neither on oxygen consumption (p=NS for all substrates) nor enzymatic activity (p=NS for all complexes).

CONCLUSIONS

Skeletal muscle mitochondria are molecularly and biochemically unaffected in PMR.

From a phagostimulant natural product to semisynthetic antifeedants against Spodoptera littoralis larvae: chemical transformations of the neoclerodane diterpenoid scutegalin B

Scutegalin B (4), a natural neoclerodane diterpenoid possessing phagostimulant activity against larvae of the lepidopteran Spodoptera littoralis, has been subjected to a series of chemical transformations obtaining several derivatives. The activity of some of these changes to antifeedant (10, 12, 16, and 17), although other derivatives are inactive (6, 7, and 15) or maintain phagostimulant activity (8 and 9) of the starting material (4). The most potent antifeedant was 16, which possesses 16,15-lactone and a (19S)-19, 2alpha-hemiacetal groups instead of the 16,15-lactol and (19R)-(19-O-tigloyl)19,2alpha-hemiacetal of the phagostimulant precursor 4. These and other structure-activity relationships are discussed, establishing that the biological action is strongly modulated by minimal structural variations.

Some biogenetic-type transformations of neoclerodane diterpenoids from Scutellaria species

Treatment of scutebaicalin (1) with K-t-BuO yielded both the (13S)- and (13R)-8beta,13-epoxyclerodanes 2 and 3, respectively, by a Michael-type heterocyclization reaction. Identical treatment of scutalpin B (4) gave the corresponding (11E)-11-deacetoxy-12-dehydro derivative 5 by an elimination reaction. Side chains at C-9, such as those of compounds 1-5, are frequent among the neoclerodanes found in Scutellaria species, and these transformations suggest a plausible biogenetic pathway for these diterpenoids.