An attempt to reduce unnecessary surgical procedures... Can ultrasound characteristics help in differentiating adenoma vs carcinoma in follicular thyroid neoplasms?

INTRODUCTION AND OBJECTIVES

Thyroid nodules frequently require ultrasound and Fine Needle Aspiration Cytology (FNAC) evaluation. However, FNA cytology does not allow differentiation between follicular adenoma and carcinoma on Bethesda type IV lesions. This situation leads to many unnecessary surgical procedures because it is not possible to assure the benignity of the lesions, even when most of the specimens correspond to adenomas or even other benign lesions. The objective is this study is to establish if there are any US characteristics that would help us to predict the risk of malignancy of nodules with a pathological diagnosis of follicular neoplasm in order to achieve a more conservative management for non-suspicious nodules.

MATERIAL AND METHODS

We studied 61 nodules in 61 patients (51 women and 10 men) that underwent thyroid surgery and had histopathological results of either follicular adenoma or carcinoma. Different US characteristics of the nodules were analysed (composition, echogenicity, margin, calcification status, the presence of halo and overall observer suspicion of malignancy) and were correlated with the histopathological analysis.

RESULTS

We have found a statistically significant association between the presence of calcifications, ill-defined borders and overall observer suspicion or impression (defined by well-known suspicious for malignancy ultrasonographic features, such as calcification, poorly defined margin, and a markedly hypoechoic solid nodule; and benign ultrasonographic features, such as predominantly cystic echogenic composition and the presence of a perinodular hypoechogenic halo) with follicular carcinoma. However all those features have shown low sensitivities in the present study (30%, 30% and 50%, respectively). On the other hand, the absence of halo sign has shown a sensitivity of 100% and a negative predictive value (NPV) of 100% in our study.

CONCLUSIONS

The presence of calcifications, ill-defined borders and the overall impression or suspicion of malignancy associate with a higher risk for follicular carcinoma in Bethesda type IV thyroid nodules but their absence do not allow to predict benignity in these nodules. Inversely, when a halo sign lesion is observed, benign follicular neoplasm should be considered.

Geographic patterns of stress in insular lizards reveal anthropogenic and climatic signatures

Anthropization of insular ecosystems may have negative impacts on native populations of lizards, which provide core ecosystem services on islands. We aimed to identify environmental factors to explain the interlocal variation in faecal glucocorticoids, parasite intensity, and body condition in populations of insular lizards. A cross-sectional design during the summer of 2017 and 2018 was used to sample 611 adult lizards, Gallotia galloti. Interlocal variation of three stress indicators was analysed in response to environmental variables across a wide environmental gradient in Tenerife (Canary Islands): (i) concentration of faecal glucocorticoids, (ii) intensities of infection by hematic parasites, and (iii) body condition. The data, with low spatial autocorrelation, were analysed using multimodel inference and model cross-validation. Bioclimatic variables associated with the extreme hot and dry climate of summer were the most informative predictors. Interlocal variation in faecal corticosterone in males was best fitted to a model that included the maximum temperature of the warmest month, although the best predictor was habitat anthropization. The thermal annual range, associated with extreme thermal events, was positively related to faecal corticosterone in females. Extreme hot temperatures were positively related to the median parasite intensities in both sexes, while the highest mean intensities of infection were found in females from the most xeric coastal localities. None of the predictors tested, including faecal glucocorticoids, explained individual or interlocal variation in body condition. Effects of human pressure and climate change on insular populations of lizards can be additive. However, the uncoupled relationship found between body condition and the faecal glucocorticoid content suggests that current negative effects may be aggravated during drought periods in summer. Given the impact of climate change on islands, our results may be of application to other archipelagos, where lizards also play key ecological roles.

An attempt to reduce unnecessary surgical procedures... Can ultrasound characteristics help in differentiating adenoma vs carcinoma in follicular thyroid neoplasms?

INTRODUCTION AND OBJECTIVES

Thyroid nodules frequently require ultrasound and Fine Needle Aspiration Cytology (FNAC) evaluation. However, FNA cytology does not allow differentiation between follicular adenoma and carcinoma on Bethesda type IV lesions. This situation leads to many unnecessary surgical procedures because it is not possible to assure the benignity of the lesions, even when most of the specimens correspond to adenomas or even other benign lesions. The objective in this study is to establish if there are any US characteristics that would help us to predict the risk of malignancy of nodules with a pathological diagnosis of follicular neoplasm in order to achieve a more conservative management for non-suspicious nodules.

MATERIAL AND METHODS

We studied 61 nodules in 61 patients (51 women and 10 men) that underwent thyroid surgery and had histopathological results of either follicular adenoma or carcinoma. Different US characteristics of the nodules were analysed (composition, echogenicity, margin, calcification status, the presence of halo and overall observer suspicion of malignancy) and were correlated with the histopathological analysis.

RESULTS

We have found a statistically significant association between the presence of calcifications, ill-defined borders and overall observer suspicion or impression (defined by well-known suspicious for malignancy ultrasonographic features, such as calcification, poorly defined margin, and a markedly hypoechoic solid nodule; and benign ultrasonographic features, such as predominantly cystic echogenic composition and the presence of a perinodular hypoechogenic halo) with follicular carcinoma. However all those features have shown low sensitivities in the present study (30%, 30% and 50%, respectively). On the other hand, the absence of halo sign has shown a sensitivity of 100% and a negative predictive value (NPV) of 100% in our study.

CONCLUSIONS

The presence of calcifications, ill-defined borders and the overall impression or suspicion of malignancy are associated with a higher risk for follicular carcinoma in Bethesda type IV thyroid nodules but their absence does not allow to predict benignity in these nodules. Inversely, when a halo sign lesion is observed, benign follicular neoplasm should be considered.

Electromagnetic behavior of dielectric objects on metallic periodically nanostructured substrates

In this research, we investigate the electromagnetic behavior of a metallic thin-film with a periodic array of subwavelength apertures when dielectric objects are located on it. The influence of size, geometry and optical properties of the objects on the transmission spectra is numerically analyzed. We study the sensitivity of this system to changes in the refractive index of the illuminated volume induced by the presence of objects with sizes from hundreds of nanometers (submicron-sized objects) to a few microns (micron-sized objects). Parameters such as the object volume within the penetration depth of the surface plasmon in the buffer medium or the contact surface between the object and the nanostructured substrate strongly affect the sensitivity. The proposed system models the presence of objects and their detection through the spectral shifts undergone by the transmission spectra. Also, we demonstrate that these can be used for obtaining information about the refractive index of a micron-sized object immersed in a buffer and located on the nanostructured sensitive surface. We believe that results found in this study can help biomedical researchers and experimentalists in the process of detecting and monitoring biological organisms of large sizes (notably, cells).

Photocatalytic degradation of aniline using an autonomous rotating drum reactor with both solar and UV-C artificial radiation

The aim of this work was to evaluate the performance of a novel self-autonomous reactor technology (capable of working with solar irradiation and artificial UV light) for water treatment using aniline as model compound. This new reactor design overcomes the problems of the external mass transfer effect and the accessibility to photons occurring in traditional reaction systems. The UV-light source is located inside the rotating quartz drums (where TiO₂ is immobilized), allowing light to easily reach the water and the TiO₂ surface. Several processes (UV, H₂O₂, Solar, TiO₂, Solar/TiO₂, Solar/TiO₂/H₂O₂ and UV/Solar/H₂O₂/TiO₂) were tested. The synergy between Solar/H₂O₂ and Solar/TiO₂ processes was quantified to be 40.3% using the pseudo-first-order degradation rate. The apparent photonic efficiency, ζ, was also determined for evaluating light utilization. For the Solar/TiO₂/H₂O₂ process, the efficiency was found to be practically constant (0.638-0.681%) when the film thickness is in the range of 1.67-3.87 μm. However, the efficiency increases up to 2.67% when artificial UV light was used in combination, confirming the efficient design of this installation. Thus, if needed, lamps can be switched on during cloudy days to improve the degradation rate of aniline and its mineralization. Under the optimal conditions selected for the Solar/TiO₂/H₂O₂ process ([H₂O₂] = 250 mg/L; pH = 4, [TiO₂] = 0.65-1.25 mg/cm²), 89.6% of aniline is degraded in 120 min. If the lamps are switched on, aniline is completely degraded in 10 min, reaching 85% of mineralization in 120 min. TiO₂ was re-used during 5 reaction cycles without apparent loss in activity (<2%). Quantification of hydroxyl radicals and dissolved oxygen allows a chemical-based explanation of the process. Finally, the UV/Solar/TiO₂/H₂O₂ process was found to have lower operation costs than other systems described in literature (0.67 €/m³).

Correlation of preoperative findings in computed axial tomography with the presence of difficult airway in patients undergoing head and neck otorhinolaryngological surgery

OBJECTIVES

To establish a correlation between 4 measurements made on preoperative computed axial tomography and the presence of difficult airway, as well as its clinical prediction in patients undergoing otorhinolaryngological surgery.

MATERIAL AND METHODS

A retrospective, observational study was carried out using the information gathered from the clinical notes of 104 patients undergoing general anaesthesia and endotracheal intubation for oncological otorhinolaryngological surgery over a period of 36 months. Based on the findings in the preoperative imaging tests, a multivariate logistic regression analysis was performed, where the dependent variable was the presence of extreme grades of visualization of the glottis visualisation (Cormack III-IV) or the presence of predictors of difficult intubation (Mallampati III-IV). This resulted in a total of 4 tomographic and clinical factors of difficult airway being introduced in this model.

RESULTS

In the Cormack III-IV group, the results were not statistically significant in the multivariate model when compared to the tomography predictors, distance from epiglottis to posterior pharyngeal wall (95% CI; 0.030 - 2.31, P<.05), and the distance from the base of the tongue to the posterior pharyngeal wall (95% CI; 0.018-1.37, P<.05). In the Mallampati III-IV group, in the multivariate model only the distance from the vocal cords to the posterior pharyngeal wall showed clinically significant results (95% CI; 0.104 - 8.53, P<.05).

CONCLUSIONS

In the approach to the airway, reliance on predictors is based on physical examination to anticipate situations that put oxygenation and ventilation of the patients at risk. There are still insufficient data to recommend imaging tests in this area, however it seems that in the future they may be added to the diagnostic performance of physical examination as predictors of difficult airway.

Colour change in a structural ornament is related to individual quality, parasites and mating patterns in the blue tit

Carry-over effects refer to processes that occur in one season and influence fitness in the following. In birds, two costly activities, namely reproduction and moult, are restricted to a small time window, and sometimes overlap. Thus, colour in newly moulted feathers is likely to be affected by the costs of reproduction. Using models of bird vision we investigated male colour change in a free-living population of blue tits (Cyanistes caeruleus) in three sampling occasions: spring 1, winter and spring 2. We related crown, tail, breast and cheek feather colouration after the moult (winter) to the intensity of infections by blood parasites during reproduction (spring 1). In the following spring (spring 2), we explored mating patterns with respect to changes in feather colour (springs 1 vs. 2). Males that were less intensely infected by the malaria parasite Plasmodium while breeding showed purer white cheek feathers in winter, which may indicate higher feather quality. Increased brightness in the white cheek was associated with better body condition during reproduction. In the following season, males with brighter cheeks paired with females that had noticeably brighter cheek patches compared to the male's previous mate. These results suggest that the conditions experienced during reproduction are likely to affect moult and thus feather colouration, at least in the white patch. High quality individuals may allocate resources efficiently during reproduction increasing future reproductive success through variation in mating patterns. Carry-over effects from reproduction might extend not only to the non-breeding phase, but also to the following breeding season.

Optofluidic chips with nanochannels for dynamic molecular detection using enhanced fluorescence

The fabrication of a novel optofluidic chip using nanochannels optimized for DNA-stretched molecules and optical detection by enhanced fluorescence is reported. The chips are composed of a series of microchannels that allow the transport of molecules in the femto-liter per second inside a fluid or gas. The nanochannels are surrounded by a photonic crystal structure to enhance the emission of fluorescent light from the molecules, which can travel along the nanochannel, allowing for enhanced optical detection of the molecules in motion. The photonic crystal structure provides an enhancement up to 2.5 times in the light emitted from fluorescent molecules inside the nanochannels which increases to around 250 when normalized to the area of the nanochannels emitting fluorescence. The results may help to the detection of fluorescent molecules (like marked-DNA) in series by speeding it and allowing the use of less sophisticated equipment.

Ageing and reproduction: antioxidant supplementation alleviates telomere loss in wild birds

Reproduction is inherently costly. Environmental stressors, such as infection and limited food resources, can compromise investment at each breeding attempt. For example, recent data on captive birds showed that increased reproductive effort accelerates ageing. However, the effects of nutritional status and infection on ageing remain unknown. Telomeres function as protective caps at the ends of eukaryotic chromosomes, and changes in telomere length is a commonly used proxy for ageing. To partially address the mechanisms of ageing following reproduction, we supplemented, medicated or administered a combined treatment to wild blue tits (Cyanistes caeruleus) breeding in central Spain during 2012. The nutritional supplement consisted of two different antioxidants, whereas the medication was an antimalarial treatment against blood parasites. We evaluated the effect of these manipulations on reproductive success and parasite loads in the first breeding season, and on changes in telomere length between two consecutive breeding seasons. Supplemented birds showed no reduction in blood parasite infections in 2012, although they exhibited higher body mass and fledging success. The antimalarial drugs reduced infections by several parasite species, but this had no effect on fitness parameters. In the following season, telomeres from supplemented birds had shortened less. Altogether, we found that supplementation with antioxidants provided fitness benefits in the short term and reduced telomere loss a year following treatment. Our results provide indirect empirical support for accelerated telomere loss as a cost of reproduction.

Aeromonas piscicola AH-3 expresses an extracellular collagenase with cytotoxic properties

The aim of this study was to investigate the presence and the phenotypic expression of a gene coding for a putative collagenase. This gene (AHA_0517) was identified in Aeromonas hydrophila ATCC 7966 genome and named colAh. We constructed and characterized an Aeromonas piscicola AH-3::colAh knockout mutant. Collagenolytic activity of the wild-type and mutant strains was determined, demonstrating that colAh encodes for a collagenase. ColAh-collagen interaction was assayed by Far-Western blot, and cytopathic effects were investigated in Vero cells. We demonstrated that ColAh is a gluzincin metallopeptidase (approx. 100 kDa), able to cleave and physically interact with collagen, that contributes for Aeromonas collagenolytic activity and cytotoxicity. ColAh possess the consensus HEXXH sequence and a glutamic acid as the third zinc binding positioned downstream the HEXXH motif, but has low sequence similarity and distinct domain architecture to the well-known clostridial collagenases. In addition, these results highlight the importance of exploring new microbial collagenases that may have significant relevance for the health and biotechnological industries.

SIGNIFICANCE AND IMPACT OF THE STUDY

Collagenases play a central role in processes where collagen digestion is needed, for example host invasion by pathogenic micro-organisms. We identified a new collagenase from Aeromonas using an integrated in silico/in vitro strategy. This enzyme is able to bind and cleave collagen, contributes for AH-3 cytotoxicity and shares low similarity with known bacterial collagenases. This is the first report of an enzyme belonging to the gluzincin subfamily of the M9 family of peptidases in Aeromonas. This study increases the current knowledge on collagenolytic enzymes bringing new perspectives for biotechnology/medical purposes.

[Clinical consequences of alpha-thalassemia in the Basque Country, Spain. Impact of neonatal screening]

INTRODUCTION

Alpha-thalassemia is the most common hemoglobinopathy with a variable clinical manifestation depending on the number of allele mutations (asymptomatic/mild anemia if 1-2 allele mutations, severe disease if 3-4 allele mutations). A study was conducted from May 2011 on hemoglobinopathies found in the neonatal screening in the autonomous community of the Basque Country (CAPV).

OBJECTIVES

To analyze the impact of alpha-thalassemia in this area and the effectiveness of its neonatal screening.

METHODS

A review was made of patients with a positive gene study for alpha-thalassemia over a 2-year period (2012-2013) and an analysis was made of the age at diagnosis, ethnic group, analytical result, and treatment.

RESULTS

The genetic study was performed on 107 patients, of which 61 had some mutation, with 62% having one allele mutations and 38% with two alleles. The mean age at diagnosis was 31 years, with 28% being younger than eighteen years old. Most of the patients were European with a significant number of Africans (26%) and Arabs (13%). All patients were asymptomatic, and 28% had mild anemia. Two patients were diagnosed by neonatal screening. Most of them did not need any treatment or only required iron therapy.

CONCLUSIONS

The detection of one or two alpha gene mutations has no clinical impact, but allows genetic counseling. No patient was found with 3-4 mutations or severe symptoms in our region. Contrarily to the diagnosis of other diseases, our results does not support that routine neonatal screening for alpha-thalassemia has any clinical impact in our community.

Isolation of three different bacteriophage from mesophilic Aeromonas sp. that use different types of monopolar flagella as their primary receptor

Bacteriophage PM4, PM5 and PM6 were isolated on different mesophilic Aeromonas strains. These bacteriophage use the flagellum as their primary bacterial receptor since purified flagella from these strains are able to inactivate these bacteriophages, independently, and the phage-resistant mutants are aflagellate and nonmotile. Furthermore, we showed that these bacteriophage may be useful to initiate the serotyping of mesophilic Aeromonas for the H-antigen (flagellum).

Amperometric magnetoimmunoassay for the direct detection of tumor necrosis factor alpha biomarker in human serum

An amperometric immunoassay for the determination of tumor necrosis factor alpha (TNFα) protein biomarker in human serum based on the use of magnetic microbeads (MBs) and disposable screen-printed carbon electrodes (SPCEs) has been developed. The specifically modified microbeads were magnetically captured on the working electrode surface and the amperometric responses were measured at -0.20V (vs. Ag pseudo-reference electrode), upon addition of hydroquinone (HQ) as electron transfer mediator and H2O2 as the enzyme substrate. After a thorough optimization of the assay, extremely low limits of detection were achieved: 2.0pg mL(-1) (36fM) and 5.8pg mL(-1) (105fM) for standard solutions and spiked human serum, respectively. The simplicity, robustness and this clinically interesting LOD proved the developed TNFα immunoassay as a good contender for real clinical application.

Self-pelleting autoagglutination on mesophilic aeromonads belonging to serotype O: 11

Self-pelleting autoagglutination of Aeromonas hydrophila and A. sobria strains from serogroup O:11 depends on the presence of the extracellular layer peripheral to the cell membrane (S layer) and motility. To show this phenotype, strains should not fimbriate during growth.

Utility and interobserver agreement of ultrasound elastography in the detection of malignant thyroid nodules in clinical care

BACKGROUND AND PURPOSE

Malignancy correlates with hardness of tissues and US elastography can potentially analyze the stiffness of lesions. Our aim was to evaluate the utility of US elastography in the detection of malignant nodules and to investigate interobserver agreement with this technique.

MATERIALS AND METHODS

One-hundred three consecutive patients with 106 thyroid nodules were examined prospectively with conventional B-mode sonography and real-time US elastography. All patients were referred for FNAB. Conventional B-mode sonography and US elastographic examinations were performed, and images were separated and independently interpreted by 2 radiologists blinded to pathologic results. US elastogram evaluation was based on a simplified classification of stiffness based on gray-scale patterns, tumor size compared with B-mode, and margins. Interobserver agreement was studied. FNAB was used as the reference standard for the diagnosis of benign nodules, but histopathologic evaluations were performed when results suspicious for malignancy or malignant results were obtained on FNAB as well as in indeterminate lesions.

RESULTS

In our study, pattern of stiffness based on gray-scale and classification proposed were statistically significant and predicted malignancy with 100% sensitivity and 40.6% specificity. Tumor size when compared with B-mode images or margins was not statistically significant in our study. No false-negatives were found, and an NPV of 100% was seen. Interobserver agreement for US elastography was excellent in our study, with a κ index of 0.82 (95% CI).

CONCLUSIONS

We believe that US elastography is a promising technique that can assist in the evaluation of thyroid nodules and can potentially diminish the number of FNAB procedures needed. We believe that it may be useful to introduce US elastography into routine clinical practice.

Determinants of distribution and prevalence of avian malaria in blue tit populations across Europe: separating host and parasite effects

Although avian malarial parasites are globally distributed, the factors that affect the geographical distribution and local prevalence of different parasite lineages across host populations or species are still poorly understood. Based on the intense screening of avian malarial parasites in nine European blue tit populations, we studied whether distribution ranges as well as local adaptation, host specialization and phylogenetic relationships can determine the observed prevalences within populations. We found that prevalence differed consistently between parasite lineages and host populations, indicating that the transmission success of parasites is lineage specific but is partly shaped by locality-specific effects. We also found that the lineage-specific estimate of prevalence was related to the distribution range of parasites: lineages found in more host populations were generally more prevalent within these populations. Additionally, parasites with high prevalence that were also widely distributed among blue tit populations were also found to infect more host species. These findings suggest that parasites reaching high local prevalence can also realize wide distribution at a global scale that can have further consequences for host specialization. Although phylogenetic relationships among parasites did not predict prevalence, we detected a close match between a tree based on the geographic distance of the host populations and the parasite phylogenetic tree, implying that neighbouring host populations shared a related parasite fauna.

Host-parasite interactions under extreme climatic conditions

The effect that climatic changes can exert on parasitic interactions represents a multifactor problem whose results are difficult to predict. The actual impact of changes will depend on their magnitude and the physiological tolerance of affected organisms. When the change is considered extreme (i.e. unusual weather events that are at the extremes of the historical distribution for a given area), the probability of an alteration in an organisms’ homeostasis increases dramatically. However, factors determining the altered dynamics of host-parasite interactions due to an extreme change are the same as those acting in response to changes of lower magnitude. Only a deep knowledge of these factors will help to produce more accurate predictive models for the effects of extreme changes on parasitic interactions. Extreme environmental conditions may affect pathogens directly when they include free-living stages in their life-cycles and indirectly through reduced resource availability for hosts and thus reduced ability to produce efficient anti-parasite defenses, or by effects on host density affecting transmission dynamics of diseases or the frequency of intraspecific contact. What are the consequences for host-parasite interactions? Here we summarize the present knowledge on three principal factors in determining host-parasite associations; biodiversity, population density and immunocompetence. In addition, we analyzed examples of the effects of environmental alteration of anthropogenic origin on parasitic systems because the effects are analogous to that exerted by an extreme climatic change.

Influence of APOE gene polymorphisms on interferon-beta treatment response in multiple sclerosis

OBJECTIVE

Clinical trials with interferon beta in relapsing remitting multiple sclerosis (RRMS) have demonstrated a reduction in the relapse rate. Nevertheless, not all patients respond to this treatment, although there is no consensus regarding the definition of response to therapy. The reasons for this failure are not known but genetic factors probably influence this, as has been previously shown with Interleukin 10 or Interferon gamma polymorphisms. The role of apolipoprotein E (APOE) gene in MS has been investigated and does not appear to increase risk for MS or influence disease severity. Interestingly APOE variation influences response to cholinesterase inhibitor treatment in Alzheimer disease or to statins in hypercholesterolemia. This might have future implications for MS.

MATERIAL AND METHODS

We retrospectively reviewed 38 RRMS patients (32 females and 6 males) treated with interferon beta (INFbeta) over at least two years. Criteria for treatment were uniform accordingly to an "Advisory Committee for the Treatment of Multiple Sclerosis". We collected data variables including age, age of onset, clinical type or disease duration. Patients were classified, two years after the start of treatment, as responders and non-responders based upon clinical criteria available in the literature, which rely on the presence of relapses, increase of disability, or both. APOE genotype was determined from blood samples using validated polymerase chain reaction methods. Correlation between patient responding status with allele E2 or E4 was tested.

RESULTS

A total of 20 patients (52.6%) received subcutaneous INFbeta1b (Betaferón(®)), 13 (34.2%) INFbeta1a intramuscular (Avonex(®)), and 5 (13.2%) subcutaneous INFbeta1a (Rebif(®)). We found 2 patients (5.2%) heterozygous for the E2 allele and 9 (23.7%) for the E4 allele. No patient was homozygous for E2 or E4. Comparison of patients with and without E2 or E4 allele showed no significant differences in any of the ten therapy response variables assessed.

CONCLUSION

Findings of a recent meta-analysis have not supported a role for APOE in MS susceptibility or severity. We have not found, in our data, any influence of this gene in the RRMS response to INFbeta. However, larger series would be required to validate these results.

Can the host immune system promote multiple invasions of erythrocytes in vivo? Differential effects of medication and host sex in a wild malaria-like model

Multiple invasions (MIs) or infections, i.e. those by more than 1 parasite in the same erythrocyte, could be the result of parasite density or, alternatively, to parasite-related factors or host-related factors. According to the last possibility, to our knowledge, only 3 laboratory studies of malaria have found an increase in the occurrence of MIs when antibodies to parasite antigens were present. Therefore, we tested the possibility that MIs were influenced by the host immune status, using as model the malaria-like parasite Haemoproteus infecting blue tits (Cyanistes caeruleus). Avian hosts infected with Haemoproteus were medicated with primaquine or injected with saline solution and the density of infection and the presence of MIs counted. Medication treatment reduced significantly the density of infection by Haemoproteus in females but not in males. For females, the presence of MIs was positively associated with both the density of infection and the immunoglobulin levels on each capture, but no association was found between the treatment and the presence of MIs. For males, the density of infection but not the immunoglobulin levels was positively associated with the presence of MIs. In addition, medicated males supported more MIs than controls. Our results represent the first line of evidence in the wild for a possible role of the host immune system promoting MIs.

Combined protocol of cell therapy for chronic spinal cord injury. Report on the electrical and functional recovery of two patients

BACKGROUND

This is a preliminary report on successful results obtained during treatment of two patients with chronic spinal cord injury. The therapeutic approach was based on the generation of controlled inflammatory activity at the injury site that induced a microenvironment for the subsequent administration of autologous, BM-driven transdifferentiated neural stem cells (NSC).

METHODS

BM mesenchymal stem cells (MSC) were cocultured with the patient's autoimmune T (AT) cells to be transdifferentiated into NSC. Forty-eight hours prior to NSC implant, patients received an i.v. infusion of 5 x 10(8) to 1 x 10(9) AT cells. NSC were infused via a feeding artery of the lesion site. Safety evaluations were performed everyday, from the day of the first infusion until 96 h after the second infusion. After treatment, patients started a Vojta and Bobath neurorehabilitation program.

RESULTS

At present two patients have been treated. Patient 1 was a 19-year-old man who presented paraplegia at the eight thoracic vertebra (T8) with his sensitive level corresponding to his sixth thoracic metamere (T6). He received two AT-NSC treatments and neurorehabilitation for 6 months. At present his motor level corresponds to his first sacral metamere (S1) and his sensitive level to the fourth sacral metamere (S4). Patient 2 was a 21-year-old woman who had a lesion that extended from her third to her fifth cervical vertebrae (C3-C5). Prior to her first therapeutic cycle she had severe quadriplegia and her sensitive level corresponded to her second cervical metamere (C2). After 3 months of treatment her motor and sensitive levels reached her first and second thoracic metameres (T1-T2). No adverse events were detected in either patient.

DISCUSSION

The preliminary results lead us to think that this minimally invasive approach, which has minor adverse events, is effective for the repair of chronic spinal cord lesions.

New data on epizootiology and genetics of piroplasms based on sequences of small ribosomal subunit and cytochrome b genes

As a continuation of our studies on molecular epizootiology of piroplasmosis in Spain and other countries, we present in this contribution the finding of new hosts for some piroplasms, as well as information on their 18S rRNA gene sequences. Genetic data were complemented with sequences of apocytochrome b gene (whenever possible). The following conclusions were drawn from these molecular studies: Theileria annulata is capable of infecting dogs, since it was diagnosed in a symptomatic animal. According to cytochrome b sequences, isolates from cows and dog present slight differences. The same isolates showed, however, identical sequence in the 18S rRNA gene. This exemplifies well the usefulness of the mitochondrial gene for examining infra-specific variation. Babesia bovis is an occasional parasite of equines, since it was detected in two symptomatic horses. We found evidence of genetic polymorphism occurring in the 18S rRNA gene of Spanish T. equi-like and B. ovis isolates. B. bennetti from Spanish seagull is loosely related to B. ovis, and might represent a genetically distinct branch of babesids. A partial sequence of a cytochrome b pseudogene was obtained for the first time in Babesia canis rossi from South Africa. The pseudogene is distantly related to B. bigemina cytochrome b gene. These new findings confirm the ability of some piroplasms to infect multiple hosts, as well as the existence of a relatively wide genetic polymorphisms with respect to the cytochrome b gene. On the other hand, the existence of mtDNA-like pseudogenes of possible nuclear location in piroplasms is interesting due to their possible impact on molecular phylogeny studies.

Tumor stem cell vaccine for NSCLC and GBM-assessment of feasibility, adverse events and efficacy

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Background: Only a small part of the total cell population of a malignancy has the potential to grow and regenerate the total tumor mass. The rest are only differentiated forms of those stem cells. This biologic characteristic seems to be responsible for the failure to achieve long term remission for several peptide based vaccines. Method: To overcome this obstacle, we have established a technique that uses tumor stem cells (TSC) to develop a TSC-B cell vaccine. To test efficacy and best administration form of this vaccine, we have proceeded as follow: First: Pieces from total or partial resections of GBM or NSCLC were mechanically dissociated to a single cell suspension. Cells were cultured in an appropriate tissue culture medium and allowed to grow for two weeks or until they reach a semi confluent stage. Then, cells were harvested and re-seeded. This procedure was repeated 6 to 24 weeks according to vitality and growth characteristics of cells. Finally, Tumor cells were fused with autologous B cells. The hybrid was kept in culture and used for an intra lymph node immunization every 3 weeks. To potentiate its action, 3 days prior to its administration we co-incubated the hybrid with either autologous dendritic cells or autologous mononuclear cells. Adverse events were evaluated by the “Common terminology criteria for Adverse Events (AE), 2004” developed by NIH. Definitions are available on the web at http://ctep.cancer.gov/reporting/ctc.html . Clinical efficacy of this procedure was evaluated according RESIST criteria for NSCLC and a combination of MRI and spectroscopy for GBM. Results: At present 8 patients with GBM with post surgical second relapse and who had received complete radiotherapy doses were treated. We have also treated 6 patients with NSCLC:4 with minimal residual disease and 2 with measurable residual disease. Patients have presented minor adverse events, mainly referred to inflammation of the injection site. The median survival rates registered to the present are 22 months for GBM patients and 3 years for patients with stage IV NSCLC who had minimal residual disease at the beginning of the treatment. Conclusion: A tumor stem cell vaccine seems to be a feasible and effective therapy with very low toxicity for the treatment of advanced GBM and NSCLC patients.

No significant financial relationships to disclose.

Identification and characterization of putative virulence genes and gene clusters in Aeromonas hydrophila PPD134/91

Aeromonas hydrophila is a gram-negative opportunistic pathogen of animals and humans. The pathogenesis of A. hydrophila is multifactorial. Genomic subtraction and markers of genomic islands (GIs) were used to identify putative virulence genes in A. hydrophila PPD134/91. Two rounds of genomic subtraction led to the identification of 22 unique DNA fragments encoding 19 putative virulence factors and seven new open reading frames, which are commonly present in the eight virulence strains examined. In addition, four GIs were found, including O-antigen, capsule, phage-associated, and type III secretion system (TTSS) gene clusters. These putative virulence genes and gene clusters were positioned on a physical map of A. hydrophila PPD134/91 to determine their genetic organization in this bacterium. Further in vivo study of insertion and deletion mutants showed that the TTSS may be one of the important virulence factors in A. hydrophila pathogenesis. Furthermore, deletions of multiple virulence factors such as S-layer, serine protease, and metalloprotease also increased the 50% lethal dose to the same level as the TTSS mutation (about 1 log) in a blue gourami infection model. This observation sheds light on the multifactorial and concerted nature of pathogenicity in A. hydrophila. The large number of putative virulence genes identified in this study will form the basis for further investigation of this emerging pathogen and help to develop effective vaccines, diagnostics, and novel therapeutics.

Are multiple gametocyte infections in malarial parasites an adaptation to ensure fertility?

Multiple infections, those by more than one parasite in the same erythrocyte, may be adaptive for the malarial parasite as a means to ensure fertility. Alternatively they may simply be the consequence of a non-adaptive process forcing several parasites to compete for resources in one host cell. Avian hosts infected withHaemoproteuswere medicated with primaquine or injected with saline solution and the density of infection and number, maturity and sex of mature multiple infections counted. Multiple infections depend on density of infection, and maturity is attained rarely and usually by gametocytes of the same sex. The role of multiple infections for fertility insurance is not supported by these results.

A type III secretion system is required for Aeromonas hydrophila AH-1 pathogenesis

Aeromonas hydrophila is a gram-negative opportunistic pathogen in fish and humans. Many bacterial pathogens of animals and plants have been shown to inject anti-host virulence determinants into the hosts via a type III secretion system (TTSS). Degenerate primers based on lcrD family genes that are present in every known TTSS allowed us to locate the TTSS gene cluster in A. hydrophila AH-1. A series of genome walking steps helped in the identification of 25 open reading frames that encode proteins homologous to those in TTSSs in other bacteria. PCR-based analysis showed the presence of lcrD homologs (ascV) in all of the 33 strains of A. hydrophila isolated from various sources. Insertional inactivation of two of the TTSS genes (aopB and aopD) led to decreased cytotoxicity in carp epithelial cells, increased phagocytosis, and reduced virulence in blue gourami. These results show that a TTSS is required for A. hydrophila pathogenesis. This is the first report of sequencing and characterization of TTSS gene clusters from A. hydrophila. The TTSS identified here may help in developing suitable vaccines as well as in further understanding of the pathogenesis of A. hydrophila.

Stress protein expression is related to tail loss in two species of iguanid lizards

During the spring of 1999, two species of iguanid lizards were captured in southern Baja California peninsula, Mexico. Blood was obtained from the tail to check for the presence of blood parasites in smears and stress proteins in cells. Levels of HSP70- and HSP60-like proteins from Sceloporus licki Van Denburgh, 1895 and Petrosaurus thalassinus (Cope, 1863) were analyzed with Western blot using antisera to human HSP60 and bovine HSP70. The potential effects of sex, tail regeneration, and haemoparasites on the expression of these proteins were also investigated. Both species differ significantly in stress protein levels and infection by haemoparasites. Petrosaurus thalassinus show the lower stress protein levels and the higher proportion of infection. Although blood parasites apparently affect the condition of P. thalassinus, stress protein levels are not significantly related with haemoparasites or condition. However, S. licki lizards showing tail regeneration have lower levels of HSP60-like protein. A negative relationship exists between the length of the regenerated part of the tail and the level of HSP60-like protein for S. licki. Based on what is known of the function of HSP60, down-regulation of the protein in blood cells may be linked to reallocation of energies to other tissues more active metabolically.

Effects of Feather Lice on Flight Behavior of Male Barn Swallows (Hirundo Rustica)

Parasites may affect host behavior in a number of ways, including their locomotory performance. We investigated whether the number of holes produced by the feather louse (Myrsidea rustica) affected flight behavior in adult male Barn Swallows (Hirundo rustica) by video-taping flight performance of individuals during escape and level flight. Percentage of time spent flapping during foraging flight was positively related to number of holes, but not to other flight parameters such as wingbeat frequency. These results suggest indirect effects of feather lice on host performance that must be considered together with effects of thermoregulation and feather breakage. This is the first report of an effect of parasite load on flight behavior.

Effects of spatial and host variables on hematozoa in white-crowned sparrows wintering in Baja California

A survey of blood parasites was conducted in February 1995 on white-crowned sparrows (Zonotrichia leucophrys) wintering in two environmentally different localities of Baja California Sur (Mexico). Blood parasite prevalence was higher in La Purísima (49%) than in San José del Cabo (8%), but there were no differences between ages or sexes within each locality. All haematozoa infections were by Haemoproteus coatneyi, except one bird in each site that were positive for Trypanosoma sp. We found no evidence for the predicted negative relationship between host body condition and intensity of parasitism. The relatively high prevalence in one site suggests that an increase of hematozoa transmission may occur in that area.

[Influence of bispectral index monitoring on fentanyl requirements during total intravenous anesthesia for major gynecological surgery]

OBJECTIVE

To determine the influence that bispectral index (BIS) monitoring of hypnosis might have on need for analgesia during surgery under total intravenous anesthesia provided by bolus administration of fentanyl.

PATIENTS AND METHOD

Prospective, randomized and partially double-blind study of 40 patients undergoing major gynecological surgery under total intravenous anesthesia with propofol and fentanyl. In the BIS group (n = 20) propofol administration was adjusted to maintain BIS between 40 and 60. In the control group (n = 20) standard doses were given: 10 mg/kg-1/h-1 after anesthetic induction and for 5 minutes, 8 mg/kg-1/h-1 over the next 5 minutes and 6 mg/kg-1/h-1 throughout the rest of the operation. All patients received intravenous bolus administration of 150 or 75 microg of fentanyl to maintain analgesia whenever systolic blood pressure and heart rate increased 20% over baseline. We compared propofol and fentanyl requirements, intraoperative changes in BIS, and awakening from anesthesia.

RESULTS

Patient and surgical characteristics were similar in both groups. BIS monitoring allowed propofol administration to be decreased a mean 24% during maintenance of anesthesia, and this in turn was associated with a significant increase in mean dose of fentanyl (415 microg versus 253 microg in the BIS and control groups, respectively; p = 0.01). Mean values of BIS were higher in the BIS group (46.4 versus 42.2; p = 0.04) and patients in the BIS group awoke sooner (in 7.7 min versus 11.1 min; p = 0.01) and tended to report less pain upon arrival at the postanesthetic recovery room, although the difference was not statistically significant.

CONCLUSIONS

BIS monitoring of depth of hypnosis can influence requirements for fentanyl during total intravenous anesthesia by bolus dosing for maintenance of analgesia. This is probably due to changes in the administration of propofol made possible by BIS monitoring.

Physiological and haematological consequences of a novel parasite on the red-rumped swallow Hirundo daurica

Parasite virulence has been hypothesised to increase with the degree of host sociality because highly social hosts have a greater probability of encountering horizontal transmission of parasites and experiencing infections with multiple strains of the same parasites than do solitary hosts. As compared with the defences of closely related social host species, we predicted that solitary hosts should have relatively weak defences against parasites, thus being relatively more affected when parasitised by a novel parasite. We tested this prediction by either experimentally infesting 12 nests of the solitarily nesting red-rumped swallow Hirundo daurica with 50 individuals of the generalist martin bug Oeciacus hirundinis or by fumigation of nine nests. Nestlings 13 days old from the parasite addition group experienced increased mortality, attained lower body mass and tended to have shorter tarsi compared to nestlings from fumigated nests. Surprisingly, nestlings from the parasite addition group had higher packed cell volume (cellular fraction of blood) and lower levels of heat shock proteins (HSP60) than nestlings from the fumigation group. A measure of immunocompetence was not significantly affected by treatment, but its magnitude was positively related to packed cell volume and negatively related to level of HSP60. Solitary hosts like the red-rumped swallow have weak immune responses and low levels of heat shock proteins when infested with ectoparasites while highly social hosts have strong immune responses and high levels of heat shock proteins when infested. These findings partially support the hypothesis that potential host species with weak defences are more susceptible to infection and the deleterious effects of evolving parasites than potential hosts with strong defences.

Synthesis, characterization, and optical response of dipolar and non-dipolar poly(phenylenevinylene) dendrimers

New dipolar and non-dipolar poly(phenylenevinylene) dendrimers bearing electron-donating and electron-withdrawing groups have been efficiently synthesized using Heck and Horner-Wadsworth-Emmons reactions. The photoluminescence of these systems may be tuned in the blue zone by choosing the appropriate peripheral groups. Despite the meta-substitution pattern, large Stokes shifts can be observed when pi-donor and pi-acceptor groups are connected by a m-phenylenevinylene system.

Synthesis and characterization of linear, hyperbranched, and dendrimer-like polymers constituted of the same repeating unit

The synthesis of a linear polymer that includes both P=N and P=S double bonds, and P-O and P-C single bonds is reported by using two different paths that involve deprotection reactions and the Staudinger reaction. The preparation of hyperbranched polymers made up of OC6H4P(Ph)2=N-P=S repeating units is also described. Five generations of dendrimers originating from the same building blocks were prepared. The characterisation of all these phosphorus-based macromolecular architectures (solution behaviour, size exclusion chromatography, intrinsic viscosity, thermal behaviour) revealed marked differences in their respective behaviour.