Revealing the stability of CuWO4/g-C3N4 nanocomposite for photocatalytic tetracycline degradation from the aqueous environment and DFT analysis.

Graphitic carbon nitride (g-C3N4) is an emerging metal-free photocatalyst, however, engineering the photocatalytic efficiency for the effective degradation of hazardous molecules is still challenging. An unstable and low bandgap CuWO4 was composited with g-C3N4 to achieve synergistic benefits of tuning the visible light responsiveness and stability of CuWO4. CuWO4/g-C3N4 nanocomposite exhibited a relatively high visible light absorption region and the bandgap was modified from 2.77 to 2.53 eV evidenced via UV-DRS. Moreover, the fast electron transfer rate was observed with CuWO4/g-C3N4 nanocomposite as confirmed using PL and photocurrent studies. XRD, FT-IR, and HR-TEM analyses signified the formation of CuWO4/g-C3N4 nanocomposite. CuWO4/g-C3N4 nanocomposite showed enhanced photocatalytic degradation of Tetracycline (TC) about ∼7.4 fold greater than pristine g-C3N4 in 120 min. Notably, the OH• and •O2- radicals played a most significant role in photocatalytic TC degradation. Furthermore, the energy band structure, density of state, and Bader charge analyses of these molecules were performed.

CO2 laser colposcopic guided surgery for the see and treat management of VHSIL: a preliminary experience.

The purpose of this study is to evaluate the efficiency of CO2 laser colposcopic guided surgery performed in an outpatient see and treat setting in the management of VHSIL. Women with a suspected diagnosis of VHSIL and no vulvoscopic suspicion of vSCC were enrolled. An electronic register of CO2 laser treatment was created where description of performing parameters (excision or ablation) was specified and personal history was recorded. Statistical analysis was performed by Fisher's exact test. Relative risks (RR) of risk factor were calculated and expressed in odds. From September 2014 to September 2018, we enrolled a total of 63 patients who underwent CO2 laser procedure and had a minimum follow-up time of 2 years at Careggi University Hospital in Florence. Forty-eight (76.2%) patients underwent laser excision and 15 (23.8%) patients underwent ablative treatment without histological results. Undertreatment was performed in 3 cases (6.3%) with definitive histology of vSCC. Therapeutical appropriateness of CO2 laser excision was reached in 85.4% of the cases (41/48). No volunteer loss to follow-up was registered; thus, fidelity to treatment was assess at 100%. Recurrence rate within 2 years attested in 8/60 followed patients (13.3%). No personal factor was found to influence the VHSIL course. CO2 laser excision may represent an excellent therapeutic option to VHSIL because it provides adequate oncological purpose with good cosmetic and functional results and high patients' loyalty to treatment. An expert team could allow to undergo patients with VHSIL suspicion to unique diagnostic and therapeutic procedure with significant benefits.

Early vs. standard screening and treatment of gestational diabetes in high-risk women - An attempt to determine relative advantages and disadvantages.

BACKGROUND AND AIMS: Screening for Gestational Diabetes (GDM) is usually recommended between 24 and 28 weeks of pregnancy; however available evidence suggests that GDM may be already present before recommended time for screening, in particular among high-risk women as those with prior GDM or obesity. The purpose of this retrospective study was to evaluate whether early screening (16-18 weeks) and treatment of GDM may improve maternal and fetal outcomes. METHODS AND RESULTS: In 290 women at high-risk for GDM, we analyzed maternal and fetal outcomes, according to early or standard screening and GDM diagnosis time. Early screening was performed by 50% of high-risk women. The prevalence of GDM was 62%. Among those who underwent early screened, GDM was diagnosed at the first evaluation in 42.7%. Women with early diagnosis were more frequently treated with insulin and had a slightly lower HbA1c than women with who were diagnosed late. No differences were observed in the prevalence of Cesarean section, operative delivery, gestational age at the delivery, macrosomia, neonatal weight, Ponderal Index and Large-for-Gestational-Age among women with early or late GDM diagnosis or NGT. However, compared to NGT women, GDM women, irrespective of the time of diagnosis, had a lower gestational weight gain, lower prevalence of macrosomia (3.9% vs. 11.4%), small (1.7% vs. 8.3%) as well as large for gestational age (3.3% vs. 16.7%), but higher prevalence of pre-term delivery (8.9% vs. 2.7%). CONCLUSION: Early vs. standard screening and treatment of GDM in high-risk women is associated with similar short-term maternal-fetal outcomes, although women with an early diagnosis were treated to a greater extent with insulin therapy.

The role of adipokines in the pathogenesis of gestational diabetes mellitus.

Gestational diabetes mellitus (GDM) is a complex condition whose physiopathology to date has not been completely clarified. Two major metabolic disorders, insulin resistance and ß-cells dysfunction, play currently major role in pathogenesis of GDM. These elements are influenced by the amount of adipose tissue present before and/or during the pregnancy. Consequently, adipokines (adiponectin (APN), leptin (LPT), adipocyte fatty acid-binding protein, resistin, visfatin, omentin, vaspin, apelin, chemerin) secreted by adipose tissue, may contribute directly and/or indirectly, through the enhancement of chronic inflammation, aggravating insulin resistance and promoting GDM onset. This review aims to outline the potential physiopathological and prognostic role in GDM of adipokines, mainly APN and LPT.

Dietary intake and major food sources of polyphenols in people with type 2 diabetes: The TOSCA.IT Study.

PURPOSE: Proper evaluation of polyphenols intake at the population level is a necessary step in order to establish possible associations with health outcomes. Available data are limited, and so far no study has been performed in people with diabetes. The aim of this work was to document the intake of polyphenols and their major food sources in a cohort of people with type 2 diabetes and in socio-demographic subgroups. METHODS: We studied 2573 men and women aged 50-75 years. Among others, anthropometry was measured by standard protocol and dietary habits were investigated by food frequency questionnaire (EPIC). The intake of polyphenols was evaluated using US Department of Agriculture and Phenol-Explorer databases. RESULTS: The mean total polyphenol intake was 683.3 ± 5.8 mg/day. Non-alcoholic beverages represented the main food source of dietary polyphenols and provided 35.5% of total polyphenol intake, followed by fruits (23.0%), alcoholic beverages (14.0%), vegetables (12.4%), cereal products and tubers (4.6%), legumes (3.7%) and oils (2.1%); chocolate, cakes and nuts are negligible sources of polyphenols in this cohort. The two most important polyphenol classes contributing to the total intake were flavonoids (47.5%) and phenolic acids (47.4%). Polyphenol intake increased with age and education level and decreased with BMI; furthermore, in the northern regions of Italy, the polyphenol intake was slightly, but significantly higher than in the central or southern regions. CONCLUSIONS: The study documents for the first time the intake of polyphenols and their main food sources in people with diabetes using validated and complete databases of the polyphenol content of food. Compared with published data, collected in people without diabetes, these results suggest a lower intake and a different pattern of intake in people with diabetes.

Production and application of O2 enriched air produced by fresh and salt water desorption in chemical plants.

Oxygen enriched air intensifies oxidation processes since smaller reactors reach the same conversion of typical unit operations that employ simple air as reactant. However, the cost to produce pure oxygen or oxygen enriched air with traditional methods, i.e. cryogenic separation or membrane technologies, may be unaffordable. Here, we propose a new continuous technology for gas mixture separation, focusing on the production of oxygen enriched air as a case study. This operation is an absorption-desorption process that takes advantage of the higher oxygen solubility in water compared to nitrogen. In a pressurized solubilisation tank, water absorbs air. Subsequently, reducing pressure desorbs oxygen enriched air. PRO/II 9.3 (Simsci-Scheider Electrics) simulated, optimized, and calculated the capital and operative expenses of this technology. Moreover, we tested for the first time salt water instead of distilled water as appealing possibility for chemical plant near sea and ocean. We varied the inlet water flowrate between 5 and 15 m3/h. The optimum operative absortion unit pressure is 15-35 barg. After degassing, water may be recycled. With salt water, the extracted quantity of enriched air decreases compared with the desorption from fresh water (20% less), while the concentration of oxygen is independent from the salt concentration. The cost of enriched air at the optimum condition is 2-3.35 EUR/Nm3.

Joint position statement on "Nutraceuticals for the treatment of hypercholesterolemia" of the Italian Society of Diabetology (SID) and of the Italian Society for the Study of Arteriosclerosis (SISA).

AIM: Evidence showed that LDL-cholesterol lowering is associated with a significant cardiovascular risk reduction. The initial therapeutic approach to hypercholesterolemia includes dietary modifications but the compliance to recommendations is often inadequate. Some dietary components with potential cholesterol-lowering activity are present in small amounts in food. Therefore, in recent years the use of "nutraceuticals" (i.e., nutrients and/or bioactive compounds with potential beneficial effects on human health) has become widespread. Such substances may be added to foods and beverages, or taken as dietary supplements (liquid preparations, tablets, capsules). In the present manuscript, the cholesterol-lowering activity of some nutraceuticals (i.e. fiber, phytosterols, soy, policosanol, red yeast rice and berberine) will be discussed along with: 1) the level of evidence on the cholesterol-lowering efficacy emerging from clinical trial; 2) the possible side effects associated with their use; 3) the categories of patients who could benefit from their use. DATA SYNTHESIS: Based on the current literature, the cholesterol-lowering effect of fiber, phytosterols and red yeast rice is consistent and supported by a good level of evidence. Over berberine, there is sufficient evidence showing significant cholesterol-lowering effects, although the results come from studies carried out almost exclusively in Asian populations. Data on the effects of soy are conflicting and, therefore, the strength of recommendation is quite low. The evidence on policosanol is inconclusive. CONCLUSION: Although health benefits may arise from the use of nutraceuticals with cholesterol-lowering activity, their use might be also associated with possible risks and pitfalls, some of which are common to all nutraceuticals whereas others are related to specific nutraceuticals.

Italian national guidelines for the screening of gestational diabetes: Time for a critical appraisal?

BACKGROUND AND AIM: In 2011, the Italian National Health System guidelines introduced a selective screening for gestational diabetes (GDM) based on risk factors, recommending early evaluation in high risk women. The present study examined to which extent guidelines are applied, and analyzed the effectiveness of GDM diagnosis according to risk profile. METHODS AND RESULTS: We analyzed 1338 pregnant women, consecutively screened for GDM with a 75 g OGTT between January 2013 and December 2015, according to national guidelines. Diagnosis of GDM was based on IADPSG/WHO 2013 criteria. As many as 14.4% of screened women was at high risk, 64% at medium, 21.6% did not have any risk factor. Only 50% of high-risk women were appropriately screened at 16th-18th gestational weeks; 28% of them repeated the OGTT due to NGT. The overall prevalence of GDM was 39.9%, higher in high risk women (67% vs. 40% medium risk vs. 22% low risk; p < 0.0001). An early GDM diagnosis was performed in 40.7% of high-risk women. In low risk women, gestational weight gain at the screening time was independently associated with GDM. CONCLUSIONS: The recommendations for the screening of GDM are still insufficiently implemented, especially for early evaluation in high risk women. Considering the high proportion of early GDM diagnosis, the poor adherence to screening recommendation may result in late diagnosis of GDM. Finally, our finding of a 22% prevalence of GDM among low risk women suggests the need to consider additional risk factors, such as excessive weight gain during pregnancy.

Micro-CT evaluation of several glide path techniques and ProTaper Next shaping outcomes in maxillary first molar curved canals.

AIM: To evaluate the ability of ProGlider instruments, PathFiles and K-files to maintain canal anatomy during glide path preparation using X-ray computed micro-tomography (micro-CT). METHODOLOGY: Forty-five extracted maxillary first permanent molars were selected. Mesio-buccal canals were randomly assigned (n = 15) to manual K-file, PathFile or ProGlider groups for glide path preparation. Irrigation was achieved with 5% NaOCl and 10% EDTA. After glide path preparation, each canal was shaped with ProTaper Next X1 and X2 to working length. Specimens were scanned (isotropic voxel size 9.1 µm) for matching volumes and surface areas and post-treatment analyses. Canal volume, surface area, centroid shift, canal geometry variation through ratio of diameter ratios and ratio of cross-sectional areas were assessed in the apical and coronal levels and at the point of maximum canal curvature. One-way factorial anovas were used to evaluate the significance of instrument in the various canal regions. RESULTS: Post-glide path analysis revealed that instrument factor was significant at the apical level for both the ratio of diameter ratios and the ratio of cross-sectional areas (P < 0.001), with an improved maintenance of root canal geometry by ProGlider and PathFile. At the coronal level and point of maximum canal curvature, ProGlider demonstrated a tendency to pre-flare the root canal compared with K-file and PathFile. PathFile and ProGlider demonstrated a significantly lower centroid shift compared with K-file at the apical level (P = 0.023). Post-shaping analysis demonstrated a more centred preparation of ProGlider, compared with PathFile and K-files, with no significant differences for other parameters. CONCLUSIONS: Use of ProGlider instruments led to less canal transportation than PathFiles and K-files.

Hormonal changes and follicular activity after treatment with intravaginal progesterone-releasing devices in llamas.

Plasma progesterone (P4 ) concentrations and follicular activity after administration of different P4 doses were evaluated in 33 adult female llamas treated with intravaginal devices. In Study 1, a group of llamas (n = 10) was treated with an intravaginal device (IVD) containing 160 (n = 5) or 780 mg of P4 (n = 5). Based on the results from the first study, in Study 2, females with follicles at different stages of development were treated with the IVD containing 780 mg of P4 (n = 21) or remain untreated (control; n = 12) to evaluate the effect of P4 on follicular activity. In Study 1, the IVD containing 160 mg of P4 induced follicular turnover in 60% of females while the remaining 40% of llamas developed persistent follicles. Thus, this device controlled follicular activity in llamas, although it promotes the persistence of follicles present at start of treatment. Conversely, in both studies, the IVD containing 780 mg of P4 suppressed follicular development and hasten the emergence of a new follicular wave in all females regardless of the follicular phase at insertion. Additionally, in Study 2, this device effectively concentrated the appearance of follicles with ovulatory diameter at a definite time after treatment in comparison with control animals. In conclusion, treatment with an IVD containing 780 mg of P4 would be considered for the control of follicular activity in llamas as it ensures the presence of a young follicle with ovulatory diameter by day 6 after the end of treatment in all females.

Oestrogen and Progesterone Receptors and COX-2 Expression in Endometrial Biopsy Samples During Maternal Recognition of Pregnancy in Llamas (Lama glama).

Endometrial expression of oestrogen receptor-α (ERα), progesterone receptor (PR) and cyclooxigenase-2 (COX-2) was evaluated in non-pregnant and pregnant llamas during the period when luteolysis/maternal recognition of pregnancy is expected to occur. Females (n = 28) were divided into two groups: non-pregnant llamas were induced to ovulate with a Buserelin injection, and endometrial biopsies were obtained on day 8 (n = 5) or 12 (n = 5) post-induction of ovulation. Animals of the pregnant group (n = 18) were mated with a fertile male. Pregnancy was confirmed by the visualization of the embryo collected by transcervical flushing in 5 of 9 animals on day 8 post-mating and by progesterone profile on day 12 post-mating in 4 of 9 animals, when endometrial biopsies were obtained. An immunohistochemical technique was used to evaluate receptors population and COX-2 expression. Pregnant llamas showed a higher percentage of positive cells and stronger intensity for ERα than for non-pregnant llamas in stroma on day 8 and in the luminal epithelium on day 12 post-induction of ovulation, while a deep decrease in endometrial PR population was reported in pregnant llamas on that day in luminal and glandular epithelia and stroma. In the luminal epithelium, COX-2 expression was lower in pregnant than in non-pregnant animals. Briefly, the increase of ERα in pregnant llamas gives further support to the hypothesis that oestrogens are involved in the mechanism of maternal recognition of pregnancy. Endometrial PR decrease in pregnant llamas might be a necessary event to allow the expression of proteins involved in conceptus attachment, a mechanism widely accepted in other species. Moreover, embryo seems to attenuate maternal PGF(2α) secretion during early pregnancy by decreasing the endometrial expression of COX-2 in the luminal epithelium of pregnant llamas.

[Asbestos at the time of the First World War]. / [L'amianto al tempo della Grande Guerra].

Between the end of the 19th century and the beginning of the 20th numerous asbestos industries began operations in various parts of the world. At the time of the First World War there is ample evidence of the use of this mineral in shipbuilding, the aircraft industry and in the construction industry. In the years 1912-17 the writer Franz Kafka was co-proprietor of a small asbestos factory in Prague. Some of the writer's novels and journal pages were inspired by this experience. In this way asbestos entered into the history of 20th century European literature. In 1917 asbestos extraction was started at the quarry in Balangero, near Turin, Italy. Risks related to the use of asbestos were known at the beginning of the 20th century and legislation aimed at preventing the harmful effects of the mineral were approved in Italy.

III Italian Consensus Conference on Malignant Mesothelioma of the Pleura. Epidemiology, Public Health and Occupational Medicine related issues.

The III Italian Consensus Conference on Pleural Mesothelioma (MM) convened on January 29th 2015. This report presents the conclusions of the 'Epidemiology, Public Health and Occupational Medicine' section. MM incidence in 2011 in Italy was 3.64 per 100,000 person/years in men and 1.32 in women. Incidence trends are starting to level off. Ten percent of cases are due to non-occupational exposure. Incidence among women is very high in Italy, because of both non-occupational and occupational exposure. The removal of asbestos in place is proceeding slowly, with remaining exposure. Recent literature confirms the causal role of chrysotile. Fibrous fluoro-edenite was classified as carcinogenic by IARC (Group 1) on the basis of MM data. A specific type (MWCNT-7) of Carbon Nanotubes was classified 2B. For pleural MM, after about 45 years since first exposure, the incidence trend slowed down; with more studies needed. Cumulative exposure is a proxy of the relevant exposure, but does not allow to distinguish if duration or intensity may possibly play a prominent role, neither to evaluate the temporal sequence of exposures. Studies showed that duration and intensity are independent determinants of MM. Blood related MM are less than 2.5%. The role of BAP1 germline mutations is limited to the BAP1 cancer syndrome, but negligible for sporadic cases. Correct MM diagnosis is baseline; guidelines agree on the importance of the tumor gross appearance and of the hematoxylin-eosin-based histology. Immunohistochemical markers contribute to diagnostic confirmation: the selection depends on morphology, location, and differential diagnosis. The WG suggested that 1) General Cancer Registries and ReNaM Regional Operational Centres (COR) interact and systematically compare MM cases; 2) ReNaM should report results presenting the diagnostic certainty codes and the diagnostic basis, separately; 3) General Cancer Registries and COR should interact with pathologists to assure the up-to-date methodology; 4) Necroscopy should be practiced for validation. Expert referral centres could contribute to the definition of uncertain cases. Health surveillance should aim to all asbestos effects. No diagnostic test is recommended for MM screening. Health surveillance should provide information on risks, medical perspective, and smoking cessation. The economic burden associated to MM was estimated in 250,000 Euro per case.

Matrix metalloproteinase (MMP)-2 and MMP-9 as inflammation markers of Trichinella spiralis and Trichinella pseudospiralis infections in mice.

Trichinella spiralis and Trichinella pseudospiralis exhibit differences in the host-parasite relationship such as the inflammatory response in parasitized muscles. Several studies indicate that matrix metalloproteinases (MMPs) represent a marker of inflammation since they regulate inflammation and immunity. The aim of this study was to evaluate the serum levels of gelatinases (MMP-9 and MMP-2) in mice experimentally infected with T. spiralis or T. pseudospiralis, to elucidate the involvement of these molecules during the inflammatory response to these parasites. Gelatin zymography on SDS polyacrilamide gels was used to assess the serum levels and in situ zymography on muscle histological sections to show the gelatinase-positive cells. In T. spiralis infected mice, the total MMP-9 serum level increased 6 days post-infection whereas, the total MMP-2 serum level increased onward. A similar trend was observed in T. pseudospiralis infected mice but the MMP-9 level was lower than that detected in T. spiralis infected mice. Significant differences were also observed in MMP-2 levels between the two experimental groups. The number of gelatinase positive cells was higher in T. spiralis than in T. pseudospiralis infected muscles. We conclude that MMP-9 and MMP-2 are markers of the inflammatory response for both T. spiralis and T. pseudospiralis infections.

Comparison of different cryoprotectants for freezing donkey (Equus asinus) semen.

The aim of this study was to evaluate two cryoprotectants, dimethylformamide (DMF) and methylformamide (MF) in two concentrations (5 and 7 %) in vitro in donkey semen using a rapid freezing technique and the effect on pregnancy rates in mares. Twenty-four ejaculates from 8 jacks (n = 8; r = 3) were divided into 4 extenders: BotuSemen Gold with 5 % or 7 % MF and 5 % or 7 % DMF, all containing 11 % lactose, 20 % egg-yolk and 0.5 % Equex. Post-thaw evaluations included: sperm motility, membrane function and acrosome status. A linear mixed effect model was used to test the effect of different freezing media on semen parameters. No differences were observed between the 4 freezing media used, for any of the seminal parameters (P > 0.05). However, samples with 5 % DMF showed the highest percentages of sperm with acrosomes and functional membranes (DMF: 5 %: 53.67 ± 22.01; 7 %: 33.92 ± 23.4; MF: 5 %: 44.5 ± 20.46; 7 %: 38.75 ± 27.4) (Data: mean ± SD; P > 0.05). Hence, thirty mares were inseminated: 15 with 5 % DMF and 15 with 7 % DMF. The pregnancy rate was 46 % (7/15) and 0 % (0/15) using the extender with 5 % or 7 % DMF, respectively (P = 0.003). To conclude, the use of 5 % or 7 % of MF or DMF did not affect the in vitro parameters. Despite the lack of differences in vitro with the two DMF concentrations, in vivo results only showed pregnancies when using 5 % DMF. Thus, the results of this study demonstrate the importance of accompanying in vitro semen evaluations with studies that evaluate post-insemination pregnancy rates.

Haematology and biochemistry in healthy llamas at sea level.

In the last years, there has been an increasing interest in llamas, not only as part of a productive system, but mostly as companion animals. Most reports regarding clinical biochemistry and haematology include few llamas and details about their health status are not available. The present study aims to provide haematological and biochemical parameters for llamas of known health status. Twenty-three non-pregnant females and seven males that live in Buenos Aires, Argentina (34°36'S, 58°22'W, at sea level) were studied. Llamas were clinically healthy, in good nutritional status. Animals were kept at grass and were fed hay bale or pellets and water ad libitum. Blood samples were collected by jugular venipuncture in spring. Packed cell volume, leucocyte count, differential white cell count, platelets count, urea, creatinine, total proteins, albumin, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, glucose, calcium and phosphate were assessed. No significant differences were observed between males and females, except for platelet count and calcium, which was greater in males (P˂0.01). Values obtained for the different parameters were similar to those previously reported, except for monocytes, alkaline phosphatase, glucose and calcium, that were lower and lymphocytes and platelets count, that were higher in this study. In conclusion, different ambient and methodological conditions might affect some parameters. The parameters hereby presented are representative of llama's population living at sea level in South America.

Integration of the mammalian shoulder girdle within populations and over evolutionary time.

Morphological integration has the potential to link morphological variation within populations with morphological evolution among species. This study begins to investigate this link by comparing integration among shoulder girdle elements (e.g. scapular blade, glenoid, coracoid, etc.) during the origin and evolution of therian mammals, and within modern bat, opossum and mouse populations. In this study, correlations among skeletal elements and patterns of allometry are used as proxies for integration. Results suggest that shoulder girdle elements tended to vary and evolve independently during the origin of mammals and subsequent radiation of placentals, consistent with the elements' distinct developmental and evolutionary origins. This finding suggests that skeletal element correlations, and therefore integration, can be conserved over large taxonomic and temporal scales. However, marsupials display a different pattern in which shoulder girdle elements tend to be more integrated, with the exception of the coracoid. This finding is consistent with a shift in the pattern of skeletal element integration coincident with the appearance of the marsupial mode of reproduction. This finding provides further evidence that development can play a significant role in the establishment of patterns of skeletal element correlation and that patterns of skeletal element correlation can themselves evolve when faced with sufficient selective pressures.

Ultrasonographic and endocrine characterization of follicular waves in llamas with a special reference to the overlapping phenomenon during successive waves.

Ovarian follicular growth in non-mated llamas occurs in successive waves that generally superimpose their origin on the regression of the preceding wave (overlapping), originating prolonged sexual receptivity in the species. The aim of this study was to perform an ultrasonographic and endocrine characterization of individual and successive waves in non-mated llamas with a special interest on the overlapping phenomenon. Twelve llamas were examined daily by transrectal ultrasonography for at least two consecutive waves. In six females, blood samples were collected daily at the end of each examination. The development of the largest follicle (F) showed a wavelike pattern with a mean duration of 25 days. All waves evaluated were partially overlapped on the preceding wave and emerged at a mean interval of 15.8 ± 0.5 days. This interwave interval determines a mean overlapping degree of 32% of the wave length. Similarly, mean plasma oestradiol-17ß (E2 ) concentrations followed a wavelike pattern. However, E2 concentrations started to decline before the structural regression of the F was observed. Mean basal E2 concentrations remain higher than 10.9 ± 0.6 pmol/l. In conclusion, follicular activity in non-mated llamas is characterized by continuous emergence of successive waves that always overlap the preceding wave with variable degrees. E2 production during the follicular wave is shorter in duration than the morphological development of the F. Finally, the overlapping phenomenon maintains increased plasma E2 concentrations persistently and this could explain the prolonged periods of sexual receptivity registered in llamas.

Oestrogen, progesterone and oxytocin receptors and COX-2 expression in endometrial biopsy samples from the induction of ovulation to luteolysis in llamas (Lama glama).

Endometrial expression of oestrogen (ERα), progesterone (PR) and oxytocin receptor (OR) and cyclooxygenase-2 (COX-2) was evaluated from the induction of ovulation to luteolysis in llamas. Ovarian activity was daily assessed by ultrasonography in five females. Ovulation was induced immediately after the detection of an ovulatory follicle by a GnRH injection (Day 0). Endometrial samples were obtained by transcervical biopsies from the left and right horns on day 0 and days 4, 8, 10 and 12 post-GnRH. Blood samples were collected daily for progesterone and estradiol-17ß determinations by RIA. An immunohistochemical technique was used to study receptors population and COX-2 expression which were then evaluated by two independent observers. The expression of ERα and PR was highest on day 0 in the luminal epithelium and stroma in association with high plasma estradiol-17ß concentrations. Thereafter, a decrease in ERα population was registered on day 4 and a new increase of its expression was observed between days 8 and 12 in those cell types. Conversely, PR population was gradually down-regulated until its lowest expression was reached on day 10 post-GnRH in the luminal epithelium. Content of OR was similar throughout the study in all cell types. The expression of COX-2 was highest from day 8 to 12 post-GnRH in the luminal epithelium, in relation to the time of maximal PGF2α release. Both steroid receptors populations and COX-2 expression were similar between horns. Meanwhile, OR expression was higher in the right than in the left uterine horn. In summary, this study showed that the loss of endometrium sensitivity to progesterone by days 8-10 post-induction of ovulation and the concomitant increase of COX-2 expression could play a key role in the mechanism of luteolysis and somehow be related to the short corpus luteum lifespan of llamas.