Avian Island Radiations Shed Light on the Dynamics of Adaptive and Nonadaptive Radiation.

Understanding the mechanisms underlying species formation and differentiation is a central goal of evolutionary biology and a formidable challenge. This understanding can provide valuable insights into the origins of the astonishing diversity of organisms living on our planet. Avian evolutionary radiations on islands have long fascinated biologists as they provide the ideal variation to study the ecological and evolutionary forces operating on the continuum between incipient lineages to complete speciation. In this review, we summarize the key insights gained from decades of research on adaptive and nonadaptive radiations of both extant and extinct insular bird species. We present a new comprehensive global list of potential avian radiations on oceanic islands, based on published island species checklists, taxonomic studies, and phylogenetic analyses. We demonstrate that our understanding of evolutionary processes is being greatly enhanced through the use of genomic tools. However, to advance the field, it is critical to complement this information with a solid understanding of the ecological and behavioral traits of both extinct and extant avian island species.

Androgen and Estrogen ß Receptor Expression Enhances Efficacy of Antihormonal Treatments in Triple-Negative Breast Cancer Cell Lines.

The triple-negative breast cancer (TNBC) subtype is characterized by the lack of expression of ERα (estrogen receptor α), PR (progesterone receptor) and no overexpression of HER-2. However, TNBC can express the androgen receptor (AR) or estrogen receptor ß (ERß). Also, TNBC secretes steroid hormones and is influenced by hormonal fluctuations, so the steroid inhibition could exert a beneficial effect in TNBC treatment. The aim of this study was to evaluate the effect of dutasteride, anastrozole and ASP9521 in in vitro processes using human TNBC cell lines. For this, immunofluorescence, sensitivity, proliferation and wound healing assays were performed, and hormone concentrations were studied. Results revealed that all TNBC cell lines expressed AR and ERß; the ones that expressed them most intensely were more sensitive to antihormonal treatments. All treatments reduced cell viability, highlighting MDA-MB-453 and SUM-159. Indeed, a decrease in androgen levels was observed in these cell lines, which could relate to a reduction in cell viability. In addition, MCF-7 and SUM-159 increased cell migration under treatments, increasing estrogen levels, which could favor cell migration. Thus, antihormonal treatments could be beneficial for TNBC therapies. This study clarifies the importance of steroid hormones in AR and ERß-positive cell lines of TNBC.

Long-Term Exposure to Isoflavones Alters the Hormonal Steroid Homeostasis-Impairing Reproductive Function in Adult Male Wistar Rats.

The consumption of isoflavones is gaining popularity worldwide due to their beneficial effects on health. However, isoflavones are considered to be endocrine disruptors and cause deleterious effects on hormone-sensitive organs, especially in males. Therefore, this study aimed to determine if a continuous and prolonged exposure to isoflavones in adult males altered the endocrine axis effect of testicular function. For this purpose, seventy-five adult male rats were administered with low and high mixtures of isoflavones (genistein and daidzein) for 5 months. The determination of steroid hormones (progesterone, androstenedione, dehydroepiandrosterone, testosterone, dihydrotestosterone, 17ß-estradiol, and estrone sulphate) was carried out in serum and testicular homogenate samples. Sperm quality parameters and testicular histology were also determined. The results revealed that low and high doses of isoflavones promote a hormonal imbalance in androgen and estrogen production, resulting in a decrease in circulating and testicular androgen levels and an increase in estrogen levels. These results are associated with a reduction in the sperm quality parameters and a reduction in the testicular weight, both in the diameter of the seminiferous tubules and the height of the germinal epithelium. Altogether, these results suggest that a continuous exposure to isoflavones in adult male rats causes a hormonal imbalance in the testes that disrupts the endocrine axis, causing defects in testicular function.

Hormonal Homologies between Canine Mammary Cancer and Human Breast Cancer in a Series of Cases.

The validity of spontaneous canine mammary cancer (CMC) as a natural model for the study of human breast cancer (HBC) from a hormonal point of view has never been thoroughly investigated. In this study, we analyzed the immunohistochemical expression of aromatase (Arom) and steroid receptors [estrogen receptor α (ER α), estrogen receptor ß (ER ß), progesterone receptor (PR) and androgen receptor (AR)] and intratumor steroid hormone levels of 17ß-estradiol (E2), estrone sulfate (SO4E1), progesterone (P4), androstenedione (A4), dehydroepiandrosterone (DHEA), and testosterone (T) in 78 samples of mammary cancer-51 human breast cancer (HBC) and 27 canine mammary cancer (CMC)-and corresponding controls. Frequency of tumors expressing Arom, ERß, PR, and AR was similar in both species, whereas ERα+ tumors were less frequent in the canine species. There was a closer similarity between premenopausal HBC and CMC. In HBC and CMC, all hormones assayed were increased in tumors compared to control samples. Intratumor androgen levels were similar in the two species, although levels of progesterone and estrogens were higher in the HBC samples than the CMC samples. Statistical associations among Arom, receptors, and hormones analyzed suggest that the major hormonal influence in both species is estrogenic through the ER, being the α isoform predominant in the human samples. Our findings further support CMC as a spontaneous model for the study of HBC, especially premenopausal HBC, although several differences, such as the more prevalent ERα immunoexpression and higher intratumor levels of estrogens and P4 in HBC, should be taken into account in comparative hormonal studies.

Blocking Estrogen Synthesis Leads to Different Hormonal Responses in Canine and Human Triple Negative Inflammatory Breast Cancer.

Blocking estrogen synthesis by inhibitors of estrogen synthesis is a widely used therapy against estrogen receptor-positive tumors. However, these therapies are less effective in negative expression tumors. Therefore, this study determined the effectiveness of anti-aromatase and anti-sulfatase therapies in canine and human inflammatory breast cancer. Cell cultures and xenografts from IPC-366 and SUM149 were treated with different doses of letrozole (anti-aromatase) and STX-64 (anti-sulfatase), in order to observe their effectiveness in terms of cell proliferation, tumor progression, and the appearance of metastases and hormonal profiles. The results revealed that both treatments are effective in vitro since they reduce cell proliferation and decrease the secreted estrogen levels. In xenograft mice, while treatment with letrozole reduces tumor progression by 30-40%, STX-64 increases tumor progression by 20%. The hormonal results obtained determined that STX-64 produced an increase in circulating and intratumoral levels of estradiol, which led to an increase in tumor progression. However, letrozole was able to block estrogen synthesis by decreasing the levels of circulating and intratumoral estrogen and thus slowing down tumor progression. In conclusion, letrozole can be an effective treatment for canine and human inflammatory breast cancer. The knowledge of the hormonal profile of breast tumors reflects useful information on the effectiveness of different endocrine treatments.

Anti-Angiogenic Treatments Interact with Steroid Secretion in Inflammatory Breast Cancer Triple Negative Cell Lines.

Human inflammatory breast cancer (IBC) is a highly angiogenic disease for which antiangiogenic therapy has demonstrated only a modest response, and the reason for this remains unknown. Thus, the purpose of this study was to determine the influence of different antiangiogenic therapies on in vitro and in vivo steroid hormone and angiogenic growth factor production using canine and human inflammatory breast carcinoma cell lines as well as the possible involvement of sex steroid hormones in angiogenesis. IPC-366 and SUM149 cell lines and xenotransplanted mice were treated with different concentrations of VEGF, SU5416, bevacizumab and celecoxib. Steroid hormone (progesterone, dehydroepiandrostenedione, androstenedione, testosterone, dihydrotestosterone, estrone sulphate and 17ß-oestradiol), angiogenic growth factors (VEGF-A, VEGF-C and VEGF-D) and IL-8 determinations in culture media, tumour homogenate and serum samples were assayed by EIA. In vitro, progesterone- and 17ß-oestradiol-induced VEGF production promoting cell proliferation and androgens are involved in the formation of vascular-like structures. In vivo, intratumoural testosterone concentrations were augmented and possibly associated with decreased metastatic rates, whereas elevated E1SO4 concentrations could promote tumour progression after antiangiogenic therapies. In conclusion, sex steroid hormones could regulate the production of angiogenic factors. The intratumoural measurement of sex steroids and growth factors may be useful to develop preventive and individualized therapeutic strategies.

Sequential colonization of oceanic archipelagos led to a species-level radiation in the common chaffinch complex (Aves: Fringilla coelebs).

Oceanic archipelagos are excellent systems for studying speciation, yet inference of evolutionary process requires that the colonization history of island organisms be known with accuracy. Here, we used phylogenomics and patterns of genetic diversity to infer the sequence and timing of colonization of Macaronesia by mainland common chaffinches (Fringilla coelebs), and assessed whether colonization of the different archipelagos has resulted in a species-level radiation. To reconstruct the evolutionary history of the complex we generated a molecular phylogeny based on genome-wide SNP loci obtained from genotyping-by-sequencing, we ran ancestral range biogeographic analyses, and assessed fine-scale genetic structure between and within archipelagos using admixture analysis. To test for a species-level radiation, we applied a probabilistic tree-based species delimitation method (mPTP) and an integrative taxonomy approach including phenotypic differences. Results revealed a circuitous colonization pathway in Macaronesia, from the mainland to the Azores, followed by Madeira, and finally the Canary Islands. The Azores showed surprisingly high genetic diversity, similar to that found on the mainland, and the other archipelagos showed the expected sequential loss of genetic diversity. Species delimitation methods supported the existence of several species within the complex. We conclude that the common chaffinch underwent a rapid radiation across Macaronesia that was driven by the sequential colonization of the different archipelagos, resulting in phenotypically and genetically distinct, independent evolutionary lineages. We recommend a taxonomic revision of the complex that takes into account its genetic and phenotypic diversity.

Longitudinal study on steroid hormone variations during the second trimester of gestation: a useful tool to confirm adequate foetal development.

BACKGROUND: The interaction of hormonal factors are crucial for good foetal development. During the second trimester of gestation, most of the main physiological processes of foetal development occur. Therefore, the aim of this study was to determine the variations in the physiological levels of cortisol, estriol, estrone sulphate, and progesterone during the second trimester (weeks 12-26) in order to establish normal ranges that can serve as indicators of foetal well-being and good functioning of the foetal-placental unit. METHODS: Saliva samples from 106 pregnant women were collected weekly (from week 12 to week 26 of gestation), and hormonal measurements were assayed by an enzyme immunoassay. The technique used for hormone measurements was highly sensitive and served as a non-invasive method for sample collection. RESULTS: The results revealed a statistically significant (p<0.05) difference between cortisol, progesterone, and oestrogens throughout the second trimester, with a more substantial relationship between oestrogens and progesterone [P4-E3 (r=0.427); P4-E1SO4 (r=0.419)]. By analysing these hormone concentrations, statistically significant (p<0.05) elevations in progesterone, cortisol, and estriol levels were found at the 16th [(P4 (0.78±0.088), C(1.99±0.116), E3(2.513±0.114)]; 18th [(P4 (1.116±0.144), C(3.409±0.137), E3(3.043±0.123)] and 23rd week of gestation [(P4(1.36±0.153), C(1.936±0.11), E3(2.657±0.07)]. Estrone sulphate levels appeared to increase progressively throughout the second trimester [from 1.103±0.03 to 2.244±0.09]. CONCLUSION: The 18th week of gestation seems to constitute a very important week during foetal adrenal development, and the analysis of the main hormones involved in foetal development, provided more precise information regarding the proper functioning of the foetal unit and foetal development.

Reproductive hormones monthly variation in free-ranging European wildcats: Lack of association with faecal marking.

Integrating ecophysiological and behavioural discoveries in conservation and management plans is essential to preserve scarce and elusive species such as the European wildcat (Felis silvestris). The purpose of this study was to characterize the monthly variation in the steroid reproductive hormone metabolite levels (oestradiol, progesterone and testosterone) in this species and to test its possible association with a monthly pattern of faecal marking. By collecting fresh faecal samples in Montes do Invernadeiro Natural Park (Galicia, Northwest Spain) each month, we obtained a total of 110 samples belonging to 25 different individuals. We conducted enzyme immunoassays which allowed us to track the annual variation in reproductive hormone excretion patterns in wildcat scats. Furthermore, we also evaluated the possible relation between the faeces used as marks and the reproductive hormone levels. We found that oestradiol and progesterone metabolite levels exhibited a distinct pattern, both increasing during the breeding months. Oestradiol metabolite larger peaks were found during March and April, whereas the highest concentration of progesterone metabolites appeared in July. On the contrary, testosterone metabolite levels did not significantly change depending on the month. Moreover, we did not find any evidence that the faecal marking behaviour pattern was associated with reproductive hormone metabolite levels. It seems that other factors related to habitat and food resources could be more important in the performance of this behaviour.

Effects of doxorubicin associated with amniotic membrane stem cells in the treatment of canine inflammatory breast carcinoma (IPC-366) cells.

BACKGROUND: Tumours in mammary glands represent the most common neoplasia in bitches, as in humans. This high incidence results in part from the stimulation of sex hormones on these glands. Among mammary tumours, inflammatory carcinoma is the most aggressive, presenting a poor prognosis to surgical treatment and chemotherapy. One of the most widely used chemotherapy drugs for breast cancer treatment is doxorubicin (DOXO). Alternative therapies have been introduced in order to assist in these treatments; studies on treatments using stem cells have emerged, since they have anti-inflammatory and immunomodulatory properties. The aim of this study was to evaluate the effects of DOXO and canine amniotic membrane stem cells (AMCs) on the triple-negative canine inflammatory mammary carcinoma cell line IPC-366. METHODS: Four experimental groups were analysed: a control group without treatment; Group I with DOXO, Group II with AMC and Group III with an association of DOXO and AMCs. We performed the MTT assay with DOXO in order to select the best concentration for the experiments. The growth curve was performed with all groups (I-III) in order to verify the potential of treatments to reduce the growth of IPC-366. For the cell cycle, all groups (I-III) were tested using propidium iodide. While in the flow cytometry, antibodies to progesterone receptor (PR), estrogen receptor (ER), PCNA, VEGF, IL-10 and TGF-ß1 were used. For steroidogenic pathway hormones, an ELISA assay was performed. RESULTS: The results showed that cells treated with 10 µg/mL DOXO showed a 71.64% reduction in cellular growth after 72 h of treatment. Reductions in the expression of VEGF and PCNA-3 were observed by flow cytometry in all treatments when compared to the control. The intracellular levels of ERs were also significantly increased in Group III (4.67% vs. 27.1%). Regarding to the levels of steroid hormones, significant increases in the levels of estradiol (E2) and estrone sulphate (S04E1) were observed in Groups I and III. On the other hand, Group II did not show differences in steroid hormone levels in relation to the control. We conclude that the association of DOXO with AMCs (Group III) promoted a reduction in cell growth and in the expression of proteins related to proliferation and angiogenesis in IPC-366 triple-negative cells. CONCLUSIONS: This treatment promoted ER positive expression, suggesting that the accumulated oestrogen conducted these cells to a synergistic state, rendering these tumour cells responsive to ERs and susceptible to new hormonal cancer therapies.

Vasculogenic mimicry-associated ultrastructural findings in human and canine inflammatory breast cancer cell lines.

BACKGROUND: Human inflammatory breast cancer (IBC) and canine inflammatory mammary cancer (IMC) are the most lethal mammary cancers. An exacerbated angiogenesis and the existence of vasculogenic mimicry (VM) are hallmarks of these tumors. The information regarding VM and ultrastructural characteristics of mammary cell lines is scant. METHODS: In this study, IBC cell line SUM149 and IMC cell line IPC-366 in adherent (2D) and non-adherent (3D) (mammospheres, cancer stem cells) conditions were analyzed by transmission and scanning electron microscopy (TEM and SEM, respectively). RESULTS: The TEM revealed round to oval shape cells with microvilli on the surface, high numbers of peroxisomes in close apposition to lipid droplets and some extracellular derived vesicles. The TEM and the SEM mammospheres revealed group of cells clumping together with a central lumen (resembling a mammary acini). The cells joint are tight junctions and zonula adherens. By SEM two cell morphologies were observed: spherical and flattened cells. There was evidence endothelial-like cells (ELCs), which is characteristic for this disease, showing several or unique cytoplasmic empty space. ELCs were more frequent in 3D than in 2D culture conditions and contained Weibel-Palade cytoplasmic bodies, which are exclusive structures of endothelial cells. CONCLUSIONS: Both cell lines, IPC-366 and SUM-149, shared ultrastructural characteristics, further supporting canine IMC as a model for the human disease. To the best of our knowledge, this is the first study that demonstrate the morphological differentiation of cultured cancer stem cells from cancer epithelial cell lines into endothelial-like cells, confirming the vasculogenic mimicry phenomenon from an ultrastructural point of view.

Effects of indole-3-carbinol on steroid hormone profile and tumor progression in a mice model of canine inflammatory mammarycancer.

BACKGROUND: Indole-3-carbinol, derived from Cruciferous vegetables is an estrogen receptor antagonist considered a preventive agent that is naturally present in diet. There are no previous studies on its effects in human inflammatory breast cancer or canine inflammatory mammary cancer that is the most aggressive type of breast cancer. METHODS: The aim of this study was to analyze the effect of indole-3-carbinol on a SCID mice xenograft model of canine inflammatory mammary cancer, using equivalent human oral dose as a preventive therapy in humans for 3 weeks. RESULTS: Indole-3-carbinol treatment decreased tumor proliferation and increased apoptosis, although tumor embolization and liver metastasis were observed in some animals. There was a characteristic subpopulation of lipid-rich cells and increased contents of select steroid hormones in tumor homogenates and serum. CONCLUSIONS: Our data reveal for the first time that the ingestion of indole-3-carbinol, as administered, diminishes proliferation and increases apoptosis of tumor cells in an experimental model of inflammatory breast cancer, although this effect could not be enough to avoid the appearance of tumor embolization and metastasis. Future clinical trials will be needed to clarify the usefulness of indole-3-carbinol in this cancer and to understand the molecular mechanisms involved.

Corticoadrenal and Cardiorespiratory Responses to Administration of Propofol Combined with Dexmedetomidine or Ketamine in Rabbits.

Anesthetic protocols may influence adrenal function. Effective methods for modulating stress are desirable to minimize secondary effects during the perioperative period. The aim of this study was to evaluate the effects of the administration of propofol with dexmedetomidine or ketamine on corticoadrenal function and heart and respiratory rates. A random treatment-order design was used: each rabbit received all treatments, with at least 14 d between experiments. Rabbits were assigned to 3 treatment groups (10 per group): group 1, 1 mL normal saline solution intravenously; group 2, propofol (3 mg/kg IV) and dexmedetomidine (0.35 mg/kg IM); and group 3, propofol (3 mg/kg IV) and ketamine (1 mg/kg IV). Dexmedetomidine was injected 15 min prior to propofol administration. Blood samples were obtained before drug administration and at 5, 10, 30, and 60 min and 24 h after injection. Serum cortisol and corticosterone levels were measured by competitive enzyme immunoassay. Serum glucocorticoid concentrations did not change in group 2. However, rabbits in group 3 showed an increase in serum cortisol (at 5-60 min) and corticosterone (at 5-120 min) when compared with all other groups at the corresponding time points. This increase probably reflected both propofol- and ketamine-associated stimulatory effects corticoadrenal function. Respiratory rate decreased in groups 2 and 3 animals, and heart rate decreased in group 2, probably due to sympathetic inhibition by propofol and dexmedetomidine. In conclusion, propofol-ketamine provides suitable cardiorespiratory stability in rabbits but enhances glucocorticoid secretion more than dexmedetomidine-propofol anesthesia. Glucocorticoid levels in anesthetized rabbits should be considered during protocol design to minimize the stress response to surgery and to avoid erroneous data interpretation.

Steroid hormone secretion in inflammatory breast cancer cell lines.

Inflammatory breast carcinoma (IBC) is a special type of breast cancer with a poor survival rate. Though several IBC cell lines have been established, recently a first IMC cell line was established. The aims of this study were: (1) to validate a highly sensitive, reliable, accurate and direct amplified enzyme immunoassay (EIA) to measure several cell-secreted steroid hormones: progesterone (P4), androstenedione (A4), testosterone (T), 17ß-estradiol (E2) and estrone sulfate (SO4E1) in the culture medium. (2) To assess whether hormone production profile by IPC-366 cells validates the IMC model for human IBC. We validated a non-competitive amplified EIA for inflammatory breast cancer cell lines based on the results of accuracy, precision, sensitivity and parallelism. The low detection limits of the technique were: P4=13.2 pg/well, A4=2.3 pg/well, T=11.4 pg/well, E2=1.9 pg/well and SO4E1=4.5 pg/well. Intra- and inter-assay coefficient of variation percentages were <10%. The mean recovery rate of hormone added to the culture medium was >90%. In all hormones studied SUM149 have higher levels (1.4 times, but not significant) than IPC-366, and the correlation index between SUM149 and IPC-366 concentrations were >97%. We can coclude that cells of both cell lines, IPC-366 and SUM149, are capable to produce steroid hormone in culture media. The presented EIA methodology is very valuable for the detection of steroid production in culture media and could be used in hormone regulation studies and therapeutic agents in cell lines of inflammatory and non-inflammatory mammary carcinoma or other cancer cell lines in preclinical studies.

Effects of Dexmedetomidine and Ketamine-Dexmedetomidine with and without Buprenorphine on Corticoadrenal Function in Rabbits.

Anesthetics may influence adrenal function and consequently alter serum glucocorticoid concentrations, leading to erroneous interpretations of results from anesthetized rabbits. However, decreases in glucocorticoid concentrations may be advantageous in protocols designed to minimize the stress response to surgery. This study characterized the variations in adrenocortical function based on changes in corticosterone and cortisol levels after various doses and combinations of dexmedetomidine, ketamine, and buprenorphine. Each rabbit received all treatments with a minimal interexperiment interval of 10 d. Rabbits were allocated to 7 groups (n = 10 per group) and received either 1 mL saline solution; dexmedetomidine at 0.05, 0.15, or 0.25 mg/kg; ketamine (35 mg/kg) and dexmedetomidine (0.25 mg/kg) without or with buprenorphine (0.03 mg/kg); or ketamine (35 mg/kg) and buprenorphine (0.03 mg/kg). Blood was sampled before drug administration and at 10, 30, 60, and 120 min and 24 h afterward. Serum glucocorticoid levels fell in all treatment groups except the one receiving ketamine-dexmedetomidine; in that group, serum glucocorticoids increased. Rabbits that received ketamine-dexmedetomidine-buprenorphine had the lowest serum glucocorticoid levels overall. In conclusion, dexmedetomidine reduces glucocorticoid secretion in rabbits but, when combined with ketamine, increases corticosterone and cortisol levels as well as heart and respiratory rates. The addition of buprenorphine to the ketamine-dexmedetomidine mixture reduces serum glucocorticoid levels. The influence of anesthetic drugs should be considered when designing a protocol to minimize the glucocorticoid response to surgery or when measuring glucocorticoid levels in rabbits.

Disentangling the complex evolutionary history of the Western Palearctic blue tits (Cyanistes spp.) - phylogenomic analyses suggest radiation by multiple colonization events and subsequent isolation.

Isolated islands and their often unique biota continue to play key roles for understanding the importance of drift, genetic variation and adaptation in the process of population differentiation and speciation. One island system that has inspired and intrigued evolutionary biologists is the blue tit complex (Cyanistes spp.) in Europe and Africa, in particular the complex evolutionary history of the multiple genetically distinct taxa of the Canary Islands. Understanding Afrocanarian colonization events is of particular importance because of recent unconventional suggestions that these island populations acted as source of the widespread population in mainland Africa. We investigated the relationship between mainland and island blue tits using a combination of Sanger sequencing at a population level (20 loci; 12 500 nucleotides) and next-generation sequencing of single population representatives (>3 200 000 nucleotides), analysed in coalescence and phylogenetic frameworks. We found (i) that Afrocanarian blue tits are monophyletic and represent four major clades, (ii) that the blue tit complex has a continental origin and that the Canary Islands were colonized three times, (iii) that all island populations have low genetic variation, indicating low long-term effective population sizes and (iv) that populations on La Palma and in Libya represent relicts of an ancestral North African population. Further, demographic reconstructions revealed (v) that the Canary Islands, conforming to traditional views, hold sink populations, which have not served as source for back colonization of the African mainland. Our study demonstrates the importance of complete taxon sampling and an extensive multimarker study design to obtain robust phylogeographical inferences.

Population history, gene flow, and bottlenecks in island populations of a secondary seed disperser, the southern grey shrike (Lanius meridionalis koenigi).

Studying the population history and demography of organisms with important ecological roles can aid understanding of evolutionary processes at the community level and inform conservation. We screened genetic variation (mtDNA and microsatellite) across the populations of the southern grey shrike (Lanius meridionalis koenigi) in the Canary Islands, where it is an endemic subspecies and an important secondary seed disperser. We show that the Canarian subspecies is polyphyletic with L. meridionalis elegans from North Africa and that shrikes have colonized the Canary Islands from North Africa multiple times. Substantial differences in genetic diversity exist across islands, which are most likely the product of a combination of historical colonization events and recent bottlenecks. The Eastern Canary Islands had the highest overall levels of genetic diversity and have probably been most recently and/or frequently colonized from Africa. Recent or ongoing bottlenecks were detected in three of the islands and are consistent with anecdotal evidence of population declines due to human disturbance. These findings are troubling given the shrike's key ecological role in the Canary Islands, and further research is needed to understand the community-level consequences of declines in shrike populations. Finally, we found moderate genetic differentiation among populations, which largely reflected the shrike's bottleneck history; however, a significant pattern of isolation-by-distance indicated that some gene flow occurs between islands. This study is a useful first step toward understanding how secondary seed dispersal operates over broad spatial scales.

Assessment of ovarian cycles in the African elephant (Loxodonta africana) by measurement of salivary progesterone metabolites.

Monitoring ovarian cycles through hormonal analysis is important in order to improve breeding management of captive elephants, and non-invasive collection techniques are particularly interesting for this purpose. However, there are some practical difficulties in collecting proper samples, and easier and more practical methods may be an advantage for some institutions and/or some animals. This study describes the development and validation of an enzymeimmunoassay (EIA) for progestins in salivary samples of African elephants, Loxodonta africana. Weekly urinary and salivary samples from five non-pregnant elephant cows aged 7-12 years were obtained for 28 weeks and analyzed using EIA. Both techniques correlated positively (r = 0.799; P < 0.001), and the cycle characteristics obtained were identical. The results clearly show that ovarian cycles can be monitored by measuring progestins from salivary samples in the African elephant. This is a simple and non-invasive method that may be a practical alternative to other sampling methods used in the species.

Increased levels of interleukins 8 and 10 as findings of canine inflammatory mammary cancer.

Inflammatory mammary cancer (IMC) is a distinct form of mammary cancer that affects dogs and women [in humans, IMC is known as inflammatory breast cancer (IBC)], and is characterized by a sudden onset and an aggressive clinical course. Spontaneous canine IMC shares epidemiologic, histopathological and clinical characteristics with the disease in humans and has been proposed as the best spontaneous animal model for studying IBC, although several aspects remain unstudied. Interleukins (ILs) play an important role in cancer as potential modulators of angiogenesis, leukocyte infiltration and tumor growth. The aims of the present study were to assess serum and tumor levels of several ILs (IL-1α, IL-1ß, IL-6, IL-8 and IL-10) by enzyme-immunoassay in dogs bearing benign and malignant mammary tumors, including dogs with IMC, for a better understanding of this disease. Forty-eight dogs were prospectively included. Animals consisted of 7 healthy Beagles used as donors for normal mammary glands (NMG) and serum controls (SCs), 10 dogs with hyperplasias and benign mammary tumors (HBMT), 24 with non-inflammatory malignant mammary tumors (non-IMC MMT) and 7 dogs with clinical and pathological IMC. IL-8 (serum) and IL-10 (serum and tissue homogenate) levels were higher in the dogs with IMC compared with the non-IMC MMT group. ILs were increased with tumor malignancy as follows: in tumor homogenates IL-6 levels were higher in malignant tumors (IMC and non-IMC MMT) versus HBMT and versus NMG and tumor IL-8 was increased in malignant tumors versus NMG; in serum, IL-1α and IL-8 levels were higher in the malignant groups respect to HBMT and SCs; interestingly, IL-10 was elevated only in the serum of IMC animals. To the best of our knowledge, this is the first report that analyzes ILs in IMC and IL-10 in canine mammary tumors. Our results indicate a role for IL-6, IL-8 and IL-10 in canine mammary malignancy and specific differences in ILs content in IMC versus non-IMC MMT that could have future diagnostic and therapeutic implications, to be confirmed in a larger series of IMC cases. These results help to support the validity of the IMC canine model for the study of human IBC and provide insight into this uncommon malignancy in dogs.

Cortisol, adrenocorticotropic hormone, serotonin, adrenaline and noradrenaline serum concentrations in relation to disease and stress in the horse.

No detailed comparative data are available on the hormonal parameters of horses suffering from a number of diseases. The aim of our study was to measure concentrations of cortisol, adrenocorticotropic hormone (ACTH), serotonin, adrenaline and noradrenaline in horses with various diseases and following surgery, to assess the response of the HPA axis and adrenal medulla. Blood samples were obtained from six groups of horses comprising a total of 119 animals as follows: laminitis, acute abdominal syndrome (AAS), castration surgery, acute diseases, chronic diseases and healthy controls. Serum hormonal concentrations were determined for each group for comparison. Statistically significant differences between all groups and controls were found for cortisol, ACTH (except for castration), serotonin and adrenaline concentrations but only in horses with laminitis and AAS for noradrenaline. No statistically significant differences were found between males and females. The largest changes in the pituitary-adrenal axis activity occurred mainly in acute diseases, laminitis and in the AAS group.