Levels of infection, pathology and nodule size of Onchocerca flexuosa (Nematoda: Onchocercidae) in red deer (Cervus elaphus) from northern Spain.

Between 2005 and 2007, the presence of Onchocerca flexuosa (Wedl, 1856) was discovered and investigated in 110 red deer (Cervus elaphus) shot in the Riaño Regional Hunting Reserve, in the province of León (north-western Spain). Nodules containing O. flexuosa were located in the dorsal region and flanks of the deer. These were collected and measured, and some adult parasites were extracted from the nodules and identified by morphology and by obtaining mitochondrial 12S rDNA sequences, which were identical to those of previously published sequences for O. flexuosa. Some nodules were prepared for histology, embedded in paraffin, sectioned and stained with haematoxylin-eosin. Histologically, the worms were found in several compartments separated by an infiltrated fibrous tissue. These compartments were inhabited by several females and males, surrounded by a fibrous capsule. A total of 85.45% (95% confidence interval (CI): 78.86-92.04%) of red deer were parasitized, with a mean intensity of 9.53 ± 12.27 nodules/host, ranging between 1 and 74 nodules/deer. Significant differences in prevalence and intensity of infection were found between young and adult red deer, and also between seasons. However, no significant differences between males and females were observed. Five hundred and ninety-seven nodules were measured (15.81 ± 3.94 mm) and classified by sizes into small ( < 10 mm), medium (10-20 mm) and large (>20 mm). No relation was found between the size of the nodules and the time of infection. The high values found in the studied parameters show that northern Spain is an area of high-intensity infection for deer.

Complement component C3 mediates Th1/Th17 polarization in human T-cell activation and cutaneous GVHD.

The complement system has been shown to regulate T-cell activation and alloimmune responses in GVHD. Mice deficient in the central component of complement system C3 have significantly lower GVHD-related mortality/morbidity, and C3 modulates Th1/Th17 polarization in mouse GVHD. To investigate whether anticomplement therapy has any impact on human T-cell activation, a drug candidate Compstatin was used to inhibit C3 activation in this study. We found the frequency of IFN-γ (Th1)-, IL-4 (Th2)-, IL-17 (Th17)-, IL-2- and TNF-α-producing cells were significantly reduced among activated CD4(+) cells in the presence of Compstatin. Compstatin treatment decreased the proliferation of both CD4(+) and CD8(+) T cells upon TCR stimulation. However, Compstatin does not affect the production of IL-2 and TNF-α in activated CD8(+) T cells, and the differentiation of CD8(+) T cells into distinct memory and effector subsets remained intact. Furthermore, we examined complement deposition in skin and lip biopsy samples of patients diagnosed with cutaneous GVHD. C3 deposition was detected in the squamous epithelium and dermis, blood vessels and damaged sweat glands, and was associated with gland damage and regeneration. We conclude that C3 mediates Th1/Th17 polarization in human T-cell activation and skin GVHD in patients.

A two-phase case-control study for colorectal cancer genetic susceptibility: candidate genes from chromosomal regions 9q22 and 3q22.

BACKGROUND: Colorectal cancer (CRC) is the second cause of cancer-related death in the Western world. Much of the CRC genetic risk remains unidentified and may be attributable to a large number of common, low-penetrance genetic variants. Genetic linkage studies in CRC families have reported additional association with regions 9q22-31, 3q21-24, 7q31, 11q, 14q and 22q. There are several plausible candidate genes for CRC susceptibility within the aforementioned linkage regions including PTCH1, XPA and TGFBR1 in 9q22-31, and EPHB1 and MRAS in 3q21-q24. METHODS: CRC cases and matched controls were from EPICOLON, a prospective, multicentre, nationwide Spanish initiative, composed of two independent phases. Phase 1 corresponded to 515 CRC cases and 515 controls, whereas phase 2 consisted of 901 CRC cases and 909 controls. Genotyping was performed for 172 single-nucleotide polymorphisms (SNPs) in 84 genes located within regions 9q22-31 and 3q21-q24. RESULTS: None of the 172 SNPs analysed in our study could be formally associated with CRC risk. However, rs1444601 (TOPBP1) and rs13088006 (CDV3) in region 3q22 showed interesting results and may have an effect on CRC risk. CONCLUSIONS: TOPBP1 and CDV3 genetic variants on region 3q22 may modulate CRC risk. Further validation and meta-analysis should be undertaken in larger CRC cohorts.

Bioética y universidad: el hospital universitario, ¿público o privado? / Bioethics and University: The University Hospital, Private or Public Institution?

Para el aprendizaje de la medicina, la práctica directa con el paciente es fundamental, con el fin de poder aplicar de manera adecuada los conocimientos teóricos. De hecho, sin esta práctica, el aprendizaje de la medicina no se consolida. Por lo tanto, el hospital se convierte en el aula docente más importante durante el entrenamiento del médico. Ancestralmente han sido los hospitales públicos, antaño de caridad, los que acogían a las facultades de medicina, concepto inherente al modelo paternalista de la medicina. Sin embargo, con el cambio de paradigma hacia una medicina respetuosa de la justicia y la autonomía, es indispensable replantearse si esta educación en sitios donde se atienden primordialmente pacientes del régimen contributivo o subsidiado es ético. Esta discriminación atenta contra la justicia, la dignidad de las personas y su autonomía. No existen criterios reales que permitan discriminar de esta manera la educación, y ésta debe desarrollarse en todos los ámbitos: públicos y privados.

In order to acquire a real and useful knowledge of medicine, the practice in the hospital setting is indispensable. Public, former charity hospitals have been the scenary for student practice. In a paternalistic model of medicine this was understandable. Nevertheless now that the model has changed to a more respectful of autonomy and justice this discrimination appears as unethical. There are no real reasons to discriminate education in such a way. Medical education should happen in both the public and private sector.

Psicocirugía, estimulación cerebral profunda y cirugía para enfermedades psiquiátricas: El riesgo del neurodeterminismo / Psychosurgery, deep brain stimulation and surgery for psychiatric illnesses: the risk of neurodeterminism

La psicocirugía es, dentro de la neurocirugía, una forma realmente novedosa de enfrentar la patología psiquiátrica. Desde los procedimientos actualmente abandonados de Moniz, de principios del siglo XX, hasta nuestros días, no solo han avanzado las técnicas sino los conceptos filosóficos que sustentan la cirugía para la enfermedad psiquiátrica. Las actuales técnicas de estimulación cerebral profunda evitan los riesgos inherentes a las lesiones irreversibles de las antiguas técnicas ablativas, a la vez que las cirugías para patologías con componente cognitivo han dado paso a las cirugías para enfermedades con componente afectivo o motor. Sin embargo, a pesar de los avances técnicos, muchas preguntas siguen vigentes: ¿dónde reside la persona, en su cerebro o en todo su cuerpo? ¿Qué define a la persona humana, sus potencialidades cognitivas y racionales o la dualidad mente-espíritu? ¿Al morir el encéfalo, muere con él la persona? Todos estos interrogantes parten del hecho de que en nuestro mundo positivista y materialista se ha reducido la concepción de persona humana al funcionamiento encefálico. La psicocirugía, con los riesgos que tiene de alterar el comportamiento y la personalidad, nos cuestiona seriamente si, en el dilema mente-cerebro, el alma de la persona reside en la pineal, como lo planteara Descartes cinco siglos atrás.

Molecular phylogeny of clade III nematodes reveals multiple origins of tissue parasitism.

Molecular phylogenetic analyses of 113 taxa representing Ascaridida, Rhigonematida, Spirurida and Oxyurida were used to infer a more comprehensive phylogenetic hypothesis for representatives of 'clade III'. The posterior probability of multiple alignment sites was used to exclude or weight characters, yielding datasets that were analysed using maximum parsimony, likelihood, and Bayesian inference methods. Phylogenetic results were robust to differences among inference methods for most high-level taxonomic groups, but some clades were sensitive to treatments of characters reflecting differences in alignment ambiguity. Taxa representing Camallanoidea, Oxyurida, Physalopteroidea, Raphidascarididae, and Skrjabillanidae were monophyletic in all 9 analyses whereas Ascaridida, Ascarididae, Anisakidae, Cosmocercoidea, Habronematoidea, Heterocheilidae, Philometridae, Rhigonematida and Thelazioidea were never monophyletic. Some clades recovered in all trees such as Dracunculoidea and Spirurina included the vast majority of their sampled species, but were non-monophyletic due to the consistent behaviour of one or few 'rogue' taxa. Similarly, 102 of 103 clade III taxa were strongly supported as monophyletic, yet clade III was paraphyletic due to the grouping of Truttaedacnitis truttae with the outgroups. Mapping of host 'habitat' revealed that tissue-dwelling localization of nematode adults has evolved independently at least 3 times, and relationships among Spirurina and Camallanina often reflected tissue predilection rather than taxonomy.

The genus Atoxoplasma (Garnham 1950) as a junior objective synonym of the genus Isospora (Schneider 1881) species infecting birds and resurrection of Cystoisospora (Frenkel 1977) as the correct genus for Isospora species infecting mammals.

Molecular and morphological data permit a rational subdivision of the paraphyletic Isospora into 2 apparently monophyletic groups of parasites, i.e., Isospora and Cystoisospora. Atoxoplasma was determined to be a junior objective synonym for Isospora. Tetrasporozoic, diplosporocystic oocysts possessing Stieda bodies in their sporocysts belong to Isospora (Eimeriidae) and have been described principally from the feces of birds. Tetrasporozoic, diplosporocystic oocysts without Stieda bodies in their sporocysts belong to Cystoisospora (Sarcocystidae).

Observability in dynamic evolutionary models.

In the paper observability problems are considered in basic dynamic evolutionary models for sexual and asexual populations. Observability means that from the (partial) knowledge of certain phenotypic characteristics the whole evolutionary process can be uniquely recovered. Sufficient conditions are given to guarantee observability for both sexual and asexual populations near an evolutionarily stable state.

Observability in strategic models of viability selection.

Strategic models of frequency-dependent viability selection, in terms of mathematical systems theory, are considered as a dynamic observation system. Using a general sufficient condition for observability of nonlinear systems with invariant manifold, it is studied whether, observing certain phenotypic characteristics of the population, the development of its genetic state can be recovered, at least near equilibrium.

Cerebral cysticercosis in a woodchuck (Marmota monax).

A juvenile woodchuck (Marmota monax) with vestibular signs was found in Woodbridge, Ontario (Canada) and later euthanized. At necropsy there was marked distortion of the right side of the skull, where a large, fluctuant, subcutaneous mass extended under the zygomatic arch and caudally from the right eye towards the right ear. The mass was multiloculated and contained a large number of tapeworm cysticerci, each about 1 to 2 mm in diameter. The third and lateral ventricles of the brain were dilated and contained large numbers of similar cysticerci. Based on the exogenous budding of cysts and the morphology of the scolex in each cyst, they were identified as cysticerci of Taenia crassiceps. This is the first report of cerebral cysticercosis in a woodchuck.

Trace elements in king eiders and common eiders in the Canadian arctic.

We determined concentrations of selected trace elements in tissues of king and common eiders at three locations in the Canadian arctic. Renal and hepatic cadmium concentrations in king eiders at a location in the eastern arctic were among the highest ever recorded in eider ducks: there, they were higher in king eiders than in common eiders. Cadmium concentrations were lower in king eiders from the western arctic than in those from the east. In the western arctic, cadmium concentrations did not differ between species. Hepatic mercury and zinc were higher in king eiders than in common eiders. Zinc and selenium were higher in eiders from the western arctic than in those from the eastern arctic. Trace element concentrations in these two duck species were below published toxicity thresholds. Positive correlations in trace element concentrations in both species were found between total and organic hepatic mercury, renal and hepatic cadmium as well as hepatic zinc, copper, mercury, and cadmium. Body mass of common but not king eiders and spleen mass of both species were negatively correlated with mercury concentrations. In common eiders, the number of nematode parasites was positively correlated with total and organic mercury. Histopathological evidence of kidney or liver lesions that are typical of trace metal poisoning was not found. We did not find evidence to support the hypothesis that trace metal exposure may be contributing to adverse effects on the health of individuals of these species.

Aortocava fistula: experience with five patients.

Combined injuries of the aorta and inferior vena cava are rare. Mortality is over 70%, primarily from exsanguinating hemorrhage. Post-traumatic aortocava fistula can develop in survivors, who present in the postoperative period with manifestations of high output heart failure. This is a retrospective review of five male patients, age from 9 to 39 years, with aortocava fistulas that were referred with congestive heart failure, 2 days to 6 months after abdominal penetrating injuries. They had undergone surgery at another hospital and several organ injuries were treated. Retroperitoneal hematomas were not seen or were seen and left undisturbed. Four patients received a gunshot injury, had the fistula at the infrarenal level, and survived surgical repair. In one of the survivors, a left popliteal artery bullet embolism also occurred and was treated. Another patient sustained a thoracoabdominal stab injury and an aortocava fistula developed at the suprarenal level; he was in severe congestive heart failure and died during surgery. There are very few reports on this sequelae of vascular injuries at the abdominal level. Patients with aortic and cava injuries have a high mortality rate and arteriovenous fistula may develop with communicating pseudoaneurysms. If high output heart failure develops in a patient with a history of abdominal penetrating injury, an arteriovenous fistula must be suspected and arteriography will disclose the location of the fistula. Surgical treatment is necessary to prevent further heart damage. In the future endovascular procedures may have a role in the management of these difficult conditions.

Decrease in Cryptosporidium parvum oocyst infectivity in vitro by using the membrane filter dissolution method for recovering oocysts from water samples.

Exposure of Cryptosporidium parvum oocysts to solutions used for cellulose acetate membrane (CAM) dissolution filtration reduced their infectivity in HCT-8 cells. Ethanol (95% [vol/vol] and 70% [vol/vol]) alone and short exposure times to acetone decreased infectivity. These findings contrast with similar experiments using excystation assays and infectivity in mice.

Phenotypic and genotypic characterization of Cryptosporidium species and isolates.

Recent outbreaks of cryptosporidiosis from contaminated water supplies have led to a need for the detection of Cryptosporidium oocysts from various hosts and contaminating sources. The presence of nonpathogenic species or strains of Cryptosporidium is important for diagnostic purposes as there is a potential for false- positive detection of pathogenic parasites. The present review focuses on phenotypic differences and recent advances in genotypic analyses of the genus Cryptosporidium with an emphasis on detecting various isolates and identifying differences in Cryptosporidium parvum and other species in this genus. The information currently available demonstrates important patterns in DNA sequences of Cryptosporidium, and our understanding of macro- and microevolutionary patterns has increased in recent years. However, current knowledge of Cryptosporidium genetic diversity is far from complete, and the large amount of both phenotypic and genotypic data has led to problems in our understanding of the systematics of this genus.

Molecular phylogeny of the other tissue coccidia: Lankesterella and Caryospora.

Nearly complete sequences were obtained from the 18S rDNA genes of Eimeria falciformis (the type species of the genus), Caryospora bigenetica, and Lankesterella minima. Two clones of the rDNA gene from C. higenetica varied slightly in primary structure. Parsimony-based and maximum likelihood phylogenetic reconstructions with a number of other apicomplexan taxa support 2 major clades within the Eucoccidiorida, i.e., the isosporoid coccidia (consisting of Toxoplasma, Neospora, Isospora [in part], and Sarcocystis spp.) and a second clade containing Lankesterella and Caryospora spp., as well as the eimeriid coccidia (Cyclospora, Isospora [in part], and Eimeria spp.). Our observations suggest that Caryospora spp. may not belong in the family Eimeriidae but rather may be allied with the family Lankesterellidae with which they share molecular and life history similarities. This may be a third lineage of coccidian parasites that has independently evolved a unique heteroxenous transmission strategy.

Improving the rate of infectivity of Cryptosporidium parvum oocysts in cell culture using centrifugation.

Centrifugation was evaluated as a method to improve infectivity assays of Cryptosporidium parvum in cell culture using the focus detection method, an immunofluorescence-based method for detecting infectious C. parvum oocysts in vitro. Human ileocecal adenocarcinoma (HCT-8) cells were grown for 48 hr on 13-mm cover slips in 24-well microtiter plates and infected with bleach-treated C. parvum oocysts. Plates were centrifuged at 228 g for 10 min and incubated at 37 C for 5, 12, 18, 24, and 48 hr. Foci of infection were stained by immunofluorescence and enumerated using epifluorescent microscopy. Results were compared to noncentrifuged controls. Foci in centrifuged samples could be enumerated after 18 hr. According to most probable number (MPN) analysis, the number of infectious oocysts estimated at 48 hr (13,326 infectious oocysts) was reached by 18 hr in centrifuged samples. After 48 hr, there was no significant difference (P < 0.05) between centrifuged and noncentrifuged samples enumerated by number of foci or the MPN of infectious oocysts. Centrifugation may expedite detection during C. parvum infectivity assays. Furthermore, multiwell plate formats are more cost effective than traditional chamber slides.

DNA fingerprinting of Cryptosporidium parvum isolates using amplified fragment length polymorphism (AFLP).

The genetic variability of 10 Cryptosporidium parvum isolates of human and animal origin was investigated using amplified fragment length polymorphism (AFLP). Analysis of fluorescent dye-labeled amplified products was carried out using an ABI PRISMS 377 DNA sequencer and ABI PRISMS GeneScan software. One-hundred and twelve primer combinations were evaluated using a single C. parvum isolate. The patterns generated were highly reproducible. For subsequent study, a subset of 9 primer pairs that yielded 30-90 DNA fragments after the polymerase chain reaction, within the size range of 50-500 bp, was used to screen the 10 C. parvum isolates, including 7 bovine, 1 equine, and 2 of human origin. The animal isolates produced identical fingerprint patterns with every primer combination tested. Of the 2 human isolates tested, 1 of the isolates, passaged in calves, generated the same AFLP DNA banding patterns as the animal isolates, whereas the other isolate, obtained directly from human feces, produced unique patterns. Polymorphism, detected by comparison of the fingerprint patterns of the latter human isolate with the common pattern shared by all other isolates, ranged from 17 to 35% for the 9 primer pairs. The results show that AFLP is a useful method for differentiating C. parvum isolates into 2 distinct genotypes.

Cryptosporidium is more closely related to the gregarines than to coccidia as shown by phylogenetic analysis of apicomplexan parasites inferred using small-subunit ribosomal RNA gene sequences.

The phylogenetic placement of gregarine parasites (Apicomplexa: Gregarinasina) within the Apicomplexa was derived by comparison of small-subunit ribosomal RNA gene sequences. Gregarine sequences were obtained from Gregarina niphandrodes Clopton, Percival, and Janovy, 1991, and Monocystis agilis Stein, 1848 (Eugregarinorida Léger 1900), as well as from Ophriocystis elektroscirrha McLaughlin and Myers, 1970 (Neogregarinorida Grassé 1953). The sequences were aligned with several other gregarine and apicomplexan sequences from GenBank and the resulting data matrix analyzed by parsimony and maximum-likelihood methods. The gregarines form a monophyletic clade that is a sister group to Cryptosporidium spp. The gregarine/ Cryptosporidium clade is separate from the other major apicomplexan clade containing the coccidia, adeleids, piroplasms, and haemosporinids. The trees indicate that the genus Cryptosporidium has a closer phylogenetic affinity with the gregarines than with the coccidia. These results do not support the present classification of the Cryptosporidiidae in the suborder Eimerioirina Léger, 1911.

PCR-based quantitation of Cryptosporidium parvum in municipal water samples.

A PCR method for the quantitation of Cryptosporidium parvum oocysts in municipal drinking water samples was investigated. Quantitative PCR uses an internal standard (IS) template with unknown target numbers to compare to standards of known concentrations in a standard curve. The IS template was amplified using the same primers used to amplify a portion of a 358 bp gene fragment that encodes a repetitive oocyst wall protein in C. parvum. Municipal water samples spiked with known numbers of C. parvum oocysts were tested by quantitative PCR using the IS and the Digene SHARP Signal System Assay for PCR product detection. The absorbance readings for target DNA and IS templates versus the number of molecules of the target DNA were plotted to generate standard curves for estimating oocyst numbers. The method allowed the quantitation of oocysts from log 3 to log 5 spiked into municipal water samples.