Exploring the transcriptomic changes underlying recombinant vaccine efficacy against Teladorsagia circumcincta in 3-month-old lambs

Teladorsagia circumcincta is an abomasal parasitic nematode that can cause serious issues in small ruminant production, which are aggravated by drug resistance. Vaccines have been suggested as a feasible, long-lasting alternative for control since adaptation to the host's immune mechanisms by helminths develops at a much slower pace than anthelmintic resistance. Recently, a T. circumcincta recombinant subunit vaccine yielded over a 60% reduction in egg excretion and worm burden and induced strong humoral and cellular anti-helminth responses in vaccinated 3-month-old Canaria Hair Breed (CHB) lambs, but Canaria Sheep (CS) of a similar age were not protected by the vaccine. Here, we compared the transcriptomic profiles in the abomasal lymph nodes of such 3-month-old CHB and CS vaccinates 40 days after infection with T. circumcincta to understand differences in responsiveness at the molecular level. In the CS, differentially expressed genes (DEG) identified were related to general immunity processes such as antigen presentation or antimicrobial proteins and down-regulation of inflammation and immune response through regulatory T cell-associated genes. However, upregulated genes in CHB vaccinates were associated with type-2 oriented immune responses, i.e., immunoglobulin production, activation of eosinophils, as well as tissue structure and wound repair-related genes and protein metabolism pathways such as DNA and RNA processing. These results highlight potentially more optimal timing and orientation of immune responses in CHB sheep compared to CS associated with vaccine-induced protection. The data obtained in this study thus deepens our understanding of variations in responsiveness to vaccination in young lamb and provides insights for vaccine refinement strategies.

Cellular and humoral immune responses associated with protection in sheep vaccinated against Teladorsagia circumcincta

Due to increased anthelmintic resistance, complementary methods to drugs are necessary to control gastrointestinal nematodes (GIN). Vaccines are an environmentally-friendly and promising option. In a previous study, a Teladorsagia circumcincta recombinant sub-unit vaccine was administered to two sheep breeds with different levels of resistance against GIN. In the susceptible Canaria Sheep (CS) breed, vaccinates harboured smaller worms with fewer eggs in utero than the control group. Here, we extend this work, by investigating the cellular and humoral immune responses of these two sheep breeds following vaccination and experimental infection with T. circumcincta. In the vaccinated CS group, negative associations between antigen-specific IgA, IgG₂ and Globule Leukocytes (GLs) with several parasitological parameters were established as well as a higher CD4⁺/CD8⁺ ratio than in control CS animals, suggesting a key role in the protection induced by the vaccine. In the more resistant Canaria Hair Breed (CHB) sheep the vaccine did not significantly impact on the parasitological parameters studied and none of these humoral associations were observed in vaccinated CHB lambs, although CHB had higher proportions of CD4⁺ and CD8⁺ T cells within the abomasal lymph nodes, suggesting higher mucosal T cell activation. Each of the component proteins in the vaccine induced an increase in immunoglobulin levels in vaccinated groups of each breed. However, levels of immunoglobulins to only three of the antigens (Tci-MEP-1, Tci-SAA-1, Tci-ASP-1) were negatively correlated with parasitological parameters in the CS breed and they may be, at least partially, responsible for the protective effect of the vaccine in this breed. These data could be useful for improving the current vaccine prototype.

Differences within Churra breed sheep in the early immune response to the infection by Teladorsagia circumcincta

This study describes early immunological mechanisms that underlie resistance to Teladorsagia circumcincta infection in adult Churra sheep. After a first experimental infection, 6 animals were classified as resistant (RG) and 6 as susceptible (SG) to T. circumcincta infection based on their cumulative faecal egg count (cFEC) at the end of the infection. RG showed higher IgA levels against somatic antigen of T. circumcincta fourth-larvae stage (L4) in serum at day 3 post-infection (pi) (p < 0.05) and close to significance at day 21 pi (p = 0.06). Moreover, a strong negative correlation between cFEC and specific IgA was only significant in RG at day 3 pi (r = - 0.870; p < 0.05), but absent in SG. At the end of this infection, sheep were treated with moxidectin and infected again 3 weeks later to be slaughtered at day 7 pi. At necropsy, the specific IgA levels in gastric mucosa were similar between groups; the absence differences at day 7 pi could be due to a previous increase in the IgA response, probably around day 3 pi, as described during the first infection. L4 burden, 68% lower in RG than in SG, was influenced by the specific IgA in gastric mucus and the number of γδ T cells. RG group showed a positive correlation between γδ T cells and eosinophils (r = 0.900; p = 0.037); however, this correlation was not found in SG. These results show that these two phenotypes show different early immune response pattern to T. circumcincta infection in Churra sheep.

Increased susceptibility to Haemonchus contortus infection by interleukin-5 modulation of eosinophil responses in sheep

Eosinophils are prominent effector cells in immune responses against gastrointestinal nematode infections in ruminants, but their in vivo role has been hard to establish in large animals. Interleukin-5 is a key cytokine in the induction and stimulation of anti-parasitic eosinophil responses. This study attempted to modulate the eosinophil response in sheep through vaccination with recombinant interleukin-5 (rIL-5) and determine the effect on subsequent Haemonchus contortus infection. Nematode-resistant Canaria Hair Breed (CHB) sheep vaccinated with rIL-5 in Quil-A adjuvant, had lower blood eosinophil counts and higher mean worm burdens than control sheep vaccinated with Quil-A adjuvant alone. In addition, adult worms in IL-5-vaccinated sheep were significantly longer with higher eggs in utero in female worms, supporting an active role of eosinophils against adult parasites in CHB sheep. These results confirm that eosinophils can play a direct role in effective control of H contortus infection in sheep and offer a new approach to study immune responses in ruminants.

Outbreak and Eradication of Tropical Rat Mite (Acari: Macronyssidae) in a European Animal Facility

A zoonotic, opportunistic out-break of tropical rat mite Ornithonyssus bacoti [Acari: Macronyssidae; Ornithonyssus bacoti (Hirst)] in an animal facility, is described. Immunocompetent mice [Mus musculus (Linnaeus)] and rat [Rattus norvegicus (Berkenhout)] strains in a conventional health status facility suffered from scratching and allopecia and staff members suffered from pruritic, erythemato-papular lesions, presumed to be allergic in origin. O. bacoti was identified and treatment with a 0.1% ivermectin solution led to its complete erradication. Safety assessment revealed no signs of acute toxicity in any animal strain. Following this inexpensive strategy, 7 wk after the initial dose, samples were negative for the presence of acari. At the time of this report, 26 months after diagnosis, O. bacoti remains undetected.

Epidemiological survey of zoonotic helminths in feral cats in Gran Canaria island (Macaronesian archipelago-Spain)

The presence of zoonotic parasites in feral cats have been widely considered all over the world. In Gran Canaria (Macaronesian archipelago, Canary Islands, Spain) the number of feral cats has grown out of control in urban and rural areas. 48 of Felis catus captured in different Gran Canaria areas were studied. Animals were necropsied and several organs were systematically examined in order to collect and identify macroscopic parasites. In addition, coprological tests were done in 28 cats. There were no statistically significant differences in the prevalence rate among sex, age or capture area, showing an overall prevalence of helminths of 77.1%. The most common tapeworms were Dipylidium caninum (64.6%) and Taenia taeniaeformis (31.3%), followed by the nematodes Toxocara cati (20.8%), Ancylostoma tubaeforme (18.8%), Aelurostrongylusabstrusus (10.4%) and Trichuris vulpis (2.08%). We also find several eggs of Alaria alata in the small intestine of one cat (2.08%), being the first description of this trematode in cats in the Canary Islands. Aproximatelly, 40% of the studied cats harboured more than one parasite. High rates of zoonotic species found in these animals suggest the need of controling parasitic infections and preventive measures against them.

Potential role for mucosal IgA in modulating Haemonchus contortus adult worm infection in sheep

Haemonchus contortus (H. contortus) is a haematophagous parasite which causes important economic losses in small ruminants. On the island of Gran Canaria, two sheep breeds coexist which differ in their susceptibility to the infection with H. contortus; the resistant Canaria Hair Breed (CHB) sheep and the susceptible Canaria Sheep (CS) breed. The major target of resistance mechanisms in CHB sheep are directed to the adult parasite stage, reducing the worm burden, and decreased length and fecundity of surviving worms. Mucosal IgA (mIgA) has been shown to be an important regulator of immunity in Haemonchus and Teladorsagia infections; through correlations with larval stages where such mechanisms as antibody-dependent cell cytotoxicity and enzyme inhibition may mediate resistance. Here for the first time, we demonstrate a significant negative correlation between mIgA and adult worm length and fecundity only in the resistant CHB sheep. In contrast, and as reported in other sheep breeds, mIgA was only negatively correlated against the larval stage in the more susceptible CS breed. This study suggests mIgA may play a role in resistance to both larval and adult stages.

Epidemiological survey of zoonotic helminths in feral cats in Gran Canaria island (Macaronesian archipelago-Spain)

The presence of zoonotic parasites in feral cats have been widely considered all over the world. In Gran Canaria (Macaronesian archipelago, Canary Islands, Spain) the number of feral cats has grown out of control in urban and rural areas. 48 of Felis catus captured in different Gran Canaria areas were studied. Animals were necropsied and several organs were systematically examined in order to collect and identify macroscopic parasites. In addition, coprological tests were done in 28 cats. There were no statistically significant differences in the prevalence rate among sex, age or capture area, showing an overall prevalence of helminths of 77.1%. The most common tapeworms were Dipylidium caninum (64.6%) and Taenia taeniaeformis (31.3%), followed by the nematodes Toxocara cati (20.8%), Ancylostoma tubaeforme (18.8%), Aelurostrongylusabstrusus (10.4%) and Truchuris vulpis (2.08%). We also find several eggs of Alaria alata in the small intestine of one cat (2.08%), being the first description of this trematode in cats in the Canary Islands. Aproximatelly, 40% of the studied cats harboured more than one parasite. High rates of zoonotic species found in these animals suggest the need of controling parasitic infections and preventive measures against them.

Immunopathological study of parasitic cholangitis in cetaceans

This paper describes the immunophenotype of cellular inflammatory infiltrates in chronic cholangitis in six common dolphins (Delphinus delphis), four striped dolphins (Stenella coeruleoalba), three Atlantic spotted dolphins (Stenella frontalis) and one pygmy sperm whale (Kogia Breviceps) found stranded along the coasts of the Canary Islands (Spain). A panel of 5 antibodies previously tested in dolphins (anti-CD3, -IgG, -MHC class II, -S100 protein and -lysozyme) were used. The present work also reports cross reactivity with dolphin antigens of two antibodies not used to date in dolphins (anti-mouse iNOS and anti-mouse Foxp3). The most common type of cholangitis found was chronic granulomatous cholangitis, associated with the presence of the parasite Campula spp., or its eggs in bile ducts. The cellular composition of the hepatic inflammatory infiltrate associated to chronic parasitic cholangitis was closely similar to that found in the cortex of control lymph nodes, including the presence of S100(+) and MHC class II(+) dendritic-like cells in lymphoid follicles and interfollicular areas. Only occasional macrophages expressed iNOS, whereas Foxp3(+) lymphocytes were not found in any of the lesions described in the different types of cholangitis.

Biodegradation of phenol in static cultures by Penicillium chrysogenum ERK1: catalytic abilities and residual phytotoxicity

A phenol-degrading fungus was isolated from crop soils. Molecular characterization (using internal transcribed spacer, translation elongation factor and beta-tubulin gene sequences) and biochemical characterization allowed to identify the fungal strain as Penicillium chrysogenum Thom ERK1. Phenol degradation was tested at 25 degrees C under resting mycelium conditions at 6, 30, 60, 200, 350 and 400 mg/l of phenol as the only source of carbon and energy. The time required for complete phenol degradation increased at different initial phenol concentrations. Maximum specific degradation rate (0.89978 mg of phenol/day/mg of dry weight) was obtained at 200 mg/l. Biomass yield decreased at initial phenol concentrations above 60 mg/l. Catechol was identified as an intermediate metabolite by HPLC analysis and catechol dioxygenase activity was detected in plate assays, suggesting that phenol metabolism could occur via ortho fission of catechol. Wheat seeds were used as phytotoxicity indicators of phenol degradation products. It was found that these products were not phytotoxic for wheat but highly phytotoxic for phenol. The high specific degradation rates obtained under resting mycelium conditions are considered relevant for practical applications of this fungus in soil decontamination processes.

Immunoprotective effect of cysteine proteinase fractions from two Haemonchus contortus strains adapted to sheep and goats

A preliminary analysis of the significance of genetic diversity in cysteine proteinase genes has been performed simultaneously in sheep and goats, with regard to the immunological control using these enzymes against haemonchosis. For this purpose, we have studied the cross-immunoprotective effect of cysteine protease-enriched protein fractions (CPFs) in adult worms of two Haemonchus contortus strains from North America and Spain that are adapted to sheep and goats, respectively. Previous genetic analysis of cysteine proteinase genes in both strains has shown that some of loci are polymorphic and these differences are translated into changes in the amino acid sequences. However, our results show that CPFs from H. contortus adult worms have a protective effect against the parasite in both sheep and goats. These results are similar regardless of whether they were obtained from sheep or goat-adapted H. contortus strains, which could be very important in case H. contortus CPFs were commercially used in different countries, as vaccines to prevent the negative effects of this parasite. Interestingly, this experimental inoculation of both species with a heterologous strain of H. contortus contributes to the idea shown in previous studies about how difficult is the interpretation and the comparison of vaccination where strains not adapted to a specific host are used. Therefore, the challenger of using heterologous strains could provide similar results to those observed in immunised animals. This study suggests the possibility of exploring the mechanisms involved in natural protection against non-adapted strains, in order to develop strategies to control haemonchosis.

Occurrence and genotype characterization of Giardia duodenalis in goat kids from the Canary Islands, Spain

Giardia duodenalis (syn. Giardia lamblia, Giardia intestinalis) is a wide-spread intestinal protozoa of both humans and animals. Although giardiosis in goat is commonly asymptomatic, young kids may bear an enteric disease associated with persistent diarrhoea and delayed weight gain. In the present study we have analysed the occurrence of Giardia in 315 young goat kids (2-6 months old) from Gran Canaria Island (Spain) through visualization of faecal cysts. The identification of genotypes of G. duodenalis among the farms was attained by nested PCR of the triophosphate isomerase (TPI) and single PCR of beta-giardin genes and subsequent sequencing. Positive samples were found in 42.2% of the animals and 95.5% of the farms. Goat faecal specimens were positive for only livestock-associated G. duodenalis assemblage E genotype for both TPI and beta-giardin genes. The genetic analysis of these two loci revealed the presence of different haplotypes among the farms included in the survey and high homology with homologous genes from cattle and sheep. Altogether, the data presented here provide additional information to the prevalence and genetic characterization of Giardia isolates. The absence of assemblages A and B in this study suggests that zoonotic transmission of Giardia from goats could be of low epidemiological significance, although these findings should be validated in studies including other geographical areas, age groups and larger number of samples.

IGM and IGG response to 29-35-kDa Toxoplasma gondii protein fractions in experimentally infected goats

The evolution of the humoral responses of IgG and IgM against 29-35-kDa Toxoplasma gondii fractions from experimentally infected goats were studied and compared by ELISA with the use of whole T. gondii soluble extracts and 29-35-kDa electroeluted proteins as antigens. The IgM response to electroeluted proteins was detected from wk 1 to wk 3 postinfection, showing a similar evolution to that observed when T. gondii crude extracts were used as antigens. These results suggest that this group of proteins could be used for a more specific detection of anti-T. gondii IgM. In the same way, the IgG response was equivalent in both cases, although when 29-35-kDa T. gondii fractions were used as antigens, the level of specific IgGs reached a peak 2 wk before than when T. gondii crude extract was used. The detection by ELISA of anti-T. gondii IgM in goats does not seem to be affected by the presence of specific IgG in serum samples when 29-35-kDa protein fractions were used as antigens.

Influence of climatic and management factors on Eimeria infections in goats from semi-arid zones

A survey of Eimeria infections was performed in dairy goats and kids (<6 months old) of six farms from a dry desert area of Gran Canaria Island (Spain). The number of oocysts per gram of faeces (OPG) was determined by a modified McMaster technique over a total of 2,616 individual faecal samples taken from the rectum in monthly intervals. Eimeria oocysts were found in 96.1% of the samples with OPG ranging from 1 x 10(2) to 1.4 x 10(6). Kid goats had significantly (P < 0.001) higher OPG counts (46,496 +/- 5,228) than dairy females (2,225 +/- 287). Eight Eimeria species were identified, with Eimeria ninakohlyakimovae (30.0%), Eimeria arloingi (28.6%) and Eimeria alijevi (20.5%) being the most frequent species followed by Eimeria caprina (9.1%), Eimeria christenseni (4.5%), Eimeria jolchijevi (3.4%), Eimeria caprovina (3.2%) and Eimeria hirci (0.7%). Although significant differences were observed among goat groups and herds, the eight species were present in the six farms in both dairy goats and kids. The intensity of oocysts shedding was related to some factors such as the size of the herd and was further influenced by the prevailing climatic conditions of the area. The highest OPG counts were recorded during the hot season in dairy goats and close to weaning time in kids reared in small farms having no prophylactic treatments against eimeriosis.

Adsorption of p-nitrophenol on activated carbon fixed-bed

Carbon fixed-beds are usually used to remove organic contaminants. Adsorption in a carbon filter is a dynamic, non-steady process which is not yet completely understood. The objective of this paper is to establish a methodology to simplify the study of this process based on the wave theory, rapid small-scale column test and experimental design/surface response analysis. The constant pattern wave hypothesis was confirmed by the experimental data. The influence of the inlet concentration of p-nitrophenol and the flow rate on dynamic adsorption was studied at 20 degrees C following a central composite design using a second-order model. Both parameters have an important influence on the response variables studied. The methodology used is a useful tool for studying the dynamic process and shows interactions that are difficult to verify by the classical step-by-step method.

Determination of the energy potential of gases produced in the pyrolysis processes of the vegetal carbon manufacture industry

In this work, a pyrolysis plant located in Valverde de Leganes, Badajoz (SW Spain) was studied. At present, only the solid phase obtained by pyrolysis finds an application as domestic fuel. In order to analyze the feasibility of a further energetic exploitation of the plant under study, the gases flowing through the chimneys were collected at different times throughout the pyrolysis process. Next, they were characterized and quantified by gas chromatography, the energy potential of each of the gases being determined. According to the results obtained in this study, a total energy potential of 5.6 x 10(7) MJ (i.e., 1.78 MW(t)) might be generated yearly. Hence, considering an overall process yield equal to 20%, up to 358 KW(e) would be produced. This power would supply enough electric energy to the industry, the remaining being added to the common electric network.

Caprine uterine and placental osteopontin expression is distinct among epitheliochorial implanting species

Osteopontin (OPN) is the most highly up-regulated extracellular matrix/adhesion molecule in the uterus of humans and domestic animals as it becomes receptive to implantation. Studies in sheep and pigs have shown that OPN is a component of ovine and porcine histotroph characterized by a complex temporal and spatial pattern of uterine and conceptus expression involving immune, epithelial, and stromal cells. It is proposed that these expression events are orchestrated to contribute to conceptus attachment and placentation. However, differences in OPN expression between sheep and pigs have been detected that relate to differences in placentation. Therefore, this study examined OPN expression in the caprine uterus and conceptus to gain insight into mechanisms underlying OPN function(s) during pregnancy through comparative analysis of differences in placentation between pigs, sheep, and goats. Goats were hysterectomized (n = 5/day) on Days 5, 11, 13, 15, 17 or 19 of the estrous cycle, and Days 5, 11, 13, 15, 17, 19 or 25 of pregnancy. Slot-blot hybridization showed increases in endometrial OPN mRNA beginning on Day 17 of the estrous cycle and Day 19 of pregnancy. In situ hybridization localized OPN mRNA to endometrial glandular epithelium (GE), Day 25 myometrium, and cells scattered within the placenta hypothesized to be immune. Immunofluorescence microscopy detected OPN protein on the apical surface of endometrial lumenal epithelium (LE), in GE, and on conceptus (Tr). Western blot analysis detected primarily the native 70-kDa OPN protein in endometrial extracts from the estrous cycle and pregnancy, as well as in uterine flushings from pregnant goats. Co-induction of OPN and alpha-smooth muscle actin, but not desmin proteins, was observed in uterine stroma by Day 25 of pregnancy. OPN in cyclic GE, Day 25 myometrium, and desmin-negative endometrial stroma is unique and reflects subtle differences among superficial implanting species that correlate with the depth of Tr invasion.

Nematodes as indicators of wetland pollution

Since diversity suggests that changes in nematode populations or communities may be useful indicators of environmental changes including anthropogenic disturbances, in this study the following measurements were done: pH, predominant plant taxa, nematode density and diversity at different wetland points along La Tapera creek. A random sampling was carried out and data were subject to analysis t-test. In this work, neither the diversity nor the pH changed, however the latter was high and nematode density and taxa were small but without significative oscillations between stations. However, other population indices showed consistent differences between sites, which are pointing out environmental alteration throughout the creek. These preliminary results from the wetland present a description of nematode communities existing under a particular set of conditions that have not been reported previously.

Endoscopic ultrasonography features of calcified gastric cancer

Calcifications are a rare finding described in benign and malignant tumors located in any site of the body. Their presence in stomach and colon carcinomas is very rare. Most of the cases described are mucinous adenocarcinomas. We present the case of one patient with this disease studied with endoscopic ultrasonography. There were punctate calcifications in the submucosa layer that tended to take on a crown-like shape in the outer-most area, producing an acoustic shadow. The pathological study of the surgical specimen showed amorphic calcifications inside some mucin lakes. More cases need to be studied with this technique in order to define their endosonographic characteristics.

Effects of waterborne nitrite on phase I-II biotransformation in channel catfish (Ictalurus punctatus)

The effects of waterborne nitrite (3 mg/l NO2) on channel catfish were studied to evaluate changes in hematological parameters and phase I-II biotransformation in liver slices. Nitrite-exposed fish had significantly higher methemoglobin, blood and liver nitrite, and significantly lower pO2 than control fish. Total phase I-mediated metabolism of 7-ethoxycoumarin (EC) was not altered in nitrite-exposed fish compared with control fish (291 +/- 43 and 312 +/- 20 pmol/mg/h, respectively). However, phase II glucuronosyltransferase-mediated metabolism of 7-hydroxycoumarin (HC), both as a phase I metabolite of EC and as a parent substrate, was elevated in nitrite-exposed fish (204 +/- 17 and 1007 +/- 103 pmol/mg/h, respectively) as compared to control fish (149 +/- 14 and 735 +/- 87 pmol/mg/h) (P < 0.05). Sulfotransferase-mediated metabolism of HC (as a metabolite of EC and as a parent substrate) was not notably altered in nitrite-exposed fish (95 +/- 16 and 617 +/- 33 pmol/mg protein/h, respectively) as compared with control fish (118 +/- 24 and 575 +/- 55 pmol/mg/h, respectively). These studies indicate that in vivo nitrite exposure and associated changes in hematological parameters do not appear to affect hepatic phase I EC biotransformation in channel catfish. However, subtle but significant changes in phase II glucuronidation, but not sulfation activity, were observed. The mechanism of these alterations is unclear. However, the data suggest that environmentally realistic concentrations of nitrite may affect the dynamics of conjugative metabolism in exposed fish.

Vascular enumeration as a significant prognosticator for invasive breast carcinoma

PURPOSE

Vascular enumeration has been claimed to be an independent prognosticator for invasive breast cancer. Most of the studies have performed a manual count of the vessels. Few investigators have used image analyzers to reduce subjectivity in the measures. The aim of this retrospective study was to compare the manual vessel count to the counts obtained with an image analyzer and to estimate their possible prognostic influence.

MATERIALS AND METHODS

We selected 112 patients with invasive ductal carcinoma, treated with radical mastectomy followed by chemotherapy and with a minimal follow-up time of 60 months (5 years). After immunostaining with factor VIII, we performed a double count of the vessels. First, we performed a manual count following Gasparini's criteria, and second, we used an image analyzer (Microm, Barcelona, Spain) to count the vessels in eight adjacent microscopic fields with a 20x objective, to reach a total area of 0.98 mm2. The image analyzer calculated the total number of vessels, their size and also the percentage of the field occupied by the vessels.

RESULTS

In our series, vascular enumeration showed no significant association with histologic grade (Bloom-Scarff-Richardson grading), tumor size, or staging.

CONCLUSION

Vascular enumeration with both methods was an independent prognosticator for relapse-free-survival (RFS) in both node-negative and -positive patients in the univariate analysis, but only vascular enumeration with the image analyzer was an independent prognostic factor in the multivariate analysis, together with lymph node metastases.

Vascular density as a prognostic indicator for invasive ductal breast carcinoma

Estimated vascular density obtained with the aid of antibodies against endothelial cells has been claimed to be an independent prognostic indicator for invasive ductal breast carcinoma. Since 1991 most studies have counted the number of vessels with the optic microscope. We have performed immunohistochemical staining for Factor VIII on formaldehyde-fixed, paraffin-embedded primary invasive ductal carcinomas from 112 patients, with a minimal follow-up time of 60 months, who had received postoperative chemoradiation therapy. We have performed a manual count with a 20x objective of the vessels in the vascular hot-spot identified in a 4x field. We analysed the association of this factor with epidemiological risk factors, histopathological features, hormonal receptor status and p53 and c-erbB-2 expression and the influence on prognosis. In univariate analysis vascular density is a significant prognostic indicator in both node-negative and node-positive patients, together with staging, Baak's morphometric multiparametric index, tumour size and histological grade. However, in multivariate analysis only tumour staging and vascular density are independent prognostic factors in breast carcinoma.

[Carcinoma of the gastroesophageal junction following variceal sclerosis: more than a coincidence?]

In the last decade, several cases of patients with esophageal varices treated with endoscopic sclerotherapy who posteriorly developed carcinoma of the gastroesophageal junction have been reported in the literature. This may only be a coincidence, although the existence of an undemonstrated relationship direct cannot be discarded. The case of a patient diagnosed with alcoholic liver cirrhosis with portal hypertension and esophageal varices who underwent several sessions of endoscopic sclerotherapy with ethanolamine oleate is presented. During follow-up dysphagia was observed due to adenocarcinoma of the lower third of the esophagus. Carcinoma of the esophagus should be taken into account as a rare diagnostic possibility in a patient with dysphagia of recent appearance with a history of esophageal varix sclerotherapy.

Oxidative polymorphism of debrisoquine is not related to human colo-rectal cancer

The oxidative polymorphism of debrisoquine (DBQ) has been determined in 89 patients with colo-rectal cancer and in 556 normal control subjects. Four patients and 34 controls, with a metabolic ratio greater than 12.6, were classified as poor metabolisers of DBQ (n.s.). No difference was found in the distribution of the frequencies of the MR of DBQ between patients and controls. It is concluded that polymorphic oxidation of DBQ is not related to the risk of developing colo-rectal cancer in human beings.

Acetylator polymorphism in human colorectal carcinoma

Acetylator phenotype has been determined using sulfamethazine in 109 patients histologically diagnosed with colorectal carcinoma (resected in 74 patients by the time of the study) and in 96 age-matched controls. Fifty-five % of patients and 58.3% of controls were classified as slow acetylators (chi 2 = 0.11, not significant). No differences were observed in the distribution of acetylator phenotype when analyzing separately male and female, surgically treated and untreated, and colonic and rectal carcinoma patients. We conclude that acetylator polymorphism is not a genetic trait related to the risk of developing colorectal carcinoma in human beings.

Thermodynamic analysis of the activation of glycogen phosphorylase b over a range of temperatures

Equilibrium dialysis and isothermal microcalorimetry experiments have been carried out to characterize the thermodynamics of the binding of AMP to glycogen phosphorylase b (EC 2.4.1.1) at pH 6.9 over the temperature range of 25-35 degrees C. Thermal titrations were performed at each temperature in various buffer systems, which have afforded the calculation of the number of protons exchanged when the AMP binds to each site in the protein. Thermodynamic parameters were obtained for the binding of AMP to the two nucleotide and the two inhibitor sites of the dimeric enzyme. The former show positive cooperativity while the latter behave as independent binding sites. A positive delta Cp value was obtained for the AMP binding to the two N sites (1.3 and 1.4 kJ K-1 mol-1), while the delta Cp was negative for the binding to the I sites (-1.9 kJ K-1 mol-1). The application of Sturtevant's method to our data (Sturtevant, J. M. (1977) Proc. Natl. Acad. Sci. U. S. A. 74, 2236-2240) and their comparison with a similar analysis undertaken with phosphorylase a (Mateo, P. L., González, J. F., Barón, C., Lopez-Mayorga, O., and Cortijo, M. (1986) J. Biol. Chem. 261, 17067-17072) has opened the way to some understanding of the thermodynamics of the allosteric transition in the protein.

Thermodynamics of the binding of AMP to glycogen phosphorylase a

The binding of AMP to rabbit muscle glycogen phosphorylase a (EC 2.4.1.1.) has been studied by equilibrium dialysis and isothermal microcalorimetry at pH 6.9 over a temperature range of 25 degrees C to 35 degrees C. Thermal titration experiments were carried out in various buffer systems. We have found by these methods that a certain number of protons are released when the protein binds to the ligand and are taken up by the buffer. The tetramer of phosphorylase a has been shown to have four equal and independent, non-cooperative binding sites for AMP at 25 degrees C, 30 degrees C, and 35 degrees C; these sites can be assigned to the so-called nucleotide or, activator, sites in the protein. The binding constants together with the changes in Gibbs energy, enthalpy, and entropy per site for the AMP binding were calculated at each temperature. A negative delta Cp value of -2.3 +/- 0.2 J K-1 (AMP bound)-1 was obtained for this binding process. The hydrophobic and vibrational contributions of the heat capacity and entropy changes have been resolved by the method described by Sturtevant (Sturtevant, J. M. (1977) Proc. Natl. Acad. Sci. U. S. A. 74, 2236-2240). From this analysis, it appears that the binding is, in all cases, enthalpy-driven, the two entropic contributions, hydrophobic and vibrational, having opposing effects.