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1.
J Trace Elem Med Biol ; 82: 127350, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38134493

RESUMEN

BACKGROUND: Microplastics comprise a significant group of emerging environmental contaminants with the capacity to adsorb several contaminants. These, in turn, undergo bioaccumulation and biomagnification processes throughout aquatic trophic chains. METHODS: Glitter, a microplastic powder composed of a combination of polymers, and raw glitter materials were investigated herein concerning metal and metalloid content, bioavailability, and sorption processes by inductively coupled plasma mass spectrometry (ICP-MS). RESULTS: Metal and metalloid concentrations were higher in glitter than in raw glitter materials, but all were below the limits established by the Brazilian National Health Surveillance Agency. Elements present in glitter originate mainly from pigments and, thus, depend on glitter color. The bioavailability of the determined elements concerning human skin was assessed. Low desorbed concentrations in solution indicate that glitter does not represent a health risk through dermal contact concerning metal and metalloid contamination. However, several elements were shown to undergo significant desorption and adsorption processes. CONCLUSION: The findings reported herein indicate seemingly low human health risks from dermal glitter contact but reinforce glitter risks as aquatic environment metal and metalloid transport vectors.


Asunto(s)
Metaloides , Metales Pesados , Contaminantes Químicos del Agua , Humanos , Plásticos , Metaloides/análisis , Disponibilidad Biológica , Metales/análisis , Brasil , Monitoreo del Ambiente , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis
2.
Salamandra, v. 57, n. 3, p. 400-412, ago. 2021
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4018

RESUMEN

Tantilla is one of the most diverse genera among colubrids, with 67 species arranged in six phenotypically recognized species groups. Tantilla boipiranga is the most recently described species within the T. melanocephala group, and it was described based on a small type series, collected in the rupestrian grasslands of south-eastern Brazil. The morphological diversity and the phylogenetic affinity of this species remain poorly known. Here, based on the assessment of recently collected specimens in combination with results of a molecular phylogenetic analysis, we evaluate the morphological variation within T. boipiranga and its phylogenetic position. Our analyses confirm T. boipiranga as genetically distinct from its generic counterparts, and diagnosable based on a combination of colour pattern, meristic counts, and hemipenial morphology. However, contrary to its original description, the hemipenial ornamentation does not differen-tiate T. boipiranga from the highly variable T. melanocephala. In our phylogenetic analysis, T. boipiranga is retrieved as a monophyletic group, nested within the diversity of T. melanocephala and sister to a clade composed by specimens from south-eastern Brazil. Tantilla melanocephala is recovered as a highly diverse lineage, indicating the possible presence of undescribed species. Additionally, our analysis indicates that the T. coronata and T. planiceps species group are mono-phyletic, while the T. taeniata species group is paraphyletic and the only sampled species for the T. calamarina group is nested within the T. melanocephala group. Our results suggest that the phenotypic evolution within the genus is probably more complex than previously recognized, and some colouration patterns used to define the groups can in fact represent phenotypical convergences. Moreover, our phylogenetic analysis suggests a strong signal of geographical structure in the tree topology. Three main geographical lineages were found, a North American, a South American and a Central Ameri-can. The first two lineages were recovered as monophyletic, while the latter is paraphyletic, with Central American species positioned as sister groups of both, the North American and the South American clades. Although a more comprehensive phylogenetic analysis is needed, our study strongly indicates the existence of hidden diversity within the T. melanocephala group and that Tantilla represents an ideal model to evaluate the validity of phenotypical groups in snake systematics and to study the driven mechanisms of morphological evolution.

3.
Med Mycol ; 58(2): 227-239, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31095342

RESUMEN

Current antifungal drugs present poor effectiveness and there is no available vaccine for fungal infections. Thus, novel strategies to treat or prevent invasive mycosis, such as cryptococcosis, are highly desirable. One strategy is the use of immunomodulators of polysaccharide nature isolated from mushrooms. The purpose of the present work was to evaluate the immunostimulatory activity of ß-(1,3)-glucan-containing exopolysaccharides (EPS) from the edible mushrooms Auricularia auricula in phagocytes and mice infected with Cryptococcus neoformans. EPS triggered macrophages and dendritic cell activation upon binding to Dectin-1, a pattern recognition receptor of the C-type lectin receptor family. Engagement of Dectin-1 culminated in pro-inflammatory cytokine production and cell maturation via its canonical Syk-dependent pathway signaling. Furthermore, upon EPS treatment, M2-like phenotype macrophages, known to support intracellular survival and replication of C. neoformans, repolarize to M1 macrophage pattern associated with enhanced production of the microbicidal molecule nitric oxide that results in efficient killing of C. neoformans. Treatment with EPS also upregulated transcript levels of genes encoding products associated with host protection against C. neoformans and Dectin-1 mediated signaling in macrophages. Finally, orally administrated ß-glucan-containing EPS from A. auricular enhanced the survival of mice infected with C. neoformans. In conclusion, the results demonstrate that EPS from A. auricula exert immunostimulatory activity in phagocytes and induce host protection against C. neoformans, suggesting that polysaccharides from this mushroom may be promising as an adjuvant for vaccines or antifungal therapy.


Asunto(s)
Agaricales/química , Criptococosis/prevención & control , Polisacáridos Fúngicos/inmunología , Fagocitos/efectos de los fármacos , Fagocitos/inmunología , beta-Glucanos/inmunología , Animales , Criptococosis/inmunología , Cryptococcus neoformans/inmunología , Citocinas/inmunología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Células Dendríticas/microbiología , Factores Inmunológicos/farmacología , Lectinas Tipo C/inmunología , Enfermedades Pulmonares Fúngicas , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/microbiología , Ratones , Ratones Endogámicos C57BL , Fagocitos/microbiología , Transducción de Señal , beta-Glucanos/farmacología
4.
Domest Anim Endocrinol ; 62: 24-31, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28910675

RESUMEN

Two experiments were conducted with the aim of determining the effect of equine chorionic gonadotropin (eCG) administration on day 14 after insemination on ovarian response and pregnancy establishment in postpartum anestrous beef cows. In both experiments, cows were subjected to a progesterone- and estradiol-based treatment for fixed-time artificial insemination (FTAI) and were randomly allocated into 4 groups to receive or not receive eCG (400 IU) at the time of device removal and/or at 14 d after FTAI. In experiment 1, from day 14 to 22, daily ultrasonographic determinations were performed to monitor ovarian dynamics, and blood was collected to determine hormone concentrations in 60 cows. In experiment 2, confirmation of pregnancy was performed at 30 and 60 d after FTAI in 1,060 anestrous cows assigned to the same experimental design. Cows that received eCG on day 14 after FTAI showed increases in corpus luteum area (P < 0.01), follicle diameter (P < 0.05), serum progesterone concentrations (P < 0.01), and estradiol-17ß concentrations (P < 0.01), compared with cows that did not receive eCG on day 14. Pregnancy rate on day 30 was greater in those cows that received both eCG treatments (ie, at device removal and 14 d after insemination) than in those that did not receive eCG treatment (P < 0.05). In conclusion, eCG administered on day 14 after FTAI increases serum progesterone concentrations during the critical period of pregnancy in anestrous cows, and this second eCG treatment seems to have a positive effect on achieving pregnancy.


Asunto(s)
Bovinos/fisiología , Cuerpo Lúteo/efectos de los fármacos , Gonadotropinas Equinas/farmacología , Preñez , Animales , Cuerpo Lúteo/fisiología , Sincronización del Estro/fisiología , Femenino , Gonadotropinas Equinas/administración & dosificación , Inseminación Artificial/veterinaria , Periodo Posparto , Embarazo , Preñez/efectos de los fármacos
5.
Forensic Sci Int ; 257: 369-375, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26528668

RESUMEN

Very little is known about the interactions of blood and fabric and how bloodstains on fabric are formed. Whereas the blood stain size for non-absorbent surfaces depends on impact velocity, previous work has suggested that for fabrics the blood stain size is independent of impact velocity when the drop size is kept constant. Therefore, a greater understanding of the interaction of blood and fabric is required. This paper explores the possibility of using a micro computed tomography (CT) scanner to study bloodstain size and shape throughout fabrics. Two different fabrics were used: 100% cotton rib knit and 100% cotton bull drill. Bloodstains were created by dropping blood droplets from three heights; 500 mm, 1000 mm and 1500 mm. Results from the CT scanner clearly showed the bloodstain shape throughout the fabric. The blood was found to form a diamond shaped stain, with the maximum cross-sectional area 0.3-0.5mm below the surface. The bloodstain morphology depended on both the impact velocity and fabric structure.


Asunto(s)
Manchas de Sangre , Textiles , Microtomografía por Rayos X , Ciencias Forenses/métodos , Humanos , Procesamiento de Imagen Asistido por Computador
6.
Anim Reprod Sci ; 146(3-4): 111-6, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24646633

RESUMEN

The objective of this study was to evaluate the effect of equine chorionic gonadotropin (eCG) administration associated to fixed-time AI (FTAI) on follicular dynamics, ovulation, corpus luteum (CL) development and serum progesterone concentrations. Multiparous suckled Hereford cows (n=46) in anestrus with 60-75 days postpartum were used. Females received an intravaginal device containing 0.5g of progesterone during 8 days and 2mg of estradiol benzoate i.m. at device insertion. At device removal 500µg of cloprostenol and 0.5mg of estradiol cypionate were administered i.m., and FTAI was performed 52-56h later. Cows were divided into two experimental groups to receive 400IU of eCG i.m. at device removal (n=23), while control group did not receive eCG (n=23). Daily ovarian ultrasonography (7.5MHz transducer) and progesterone concentrations determined by RIA were assayed from device removal until 30 or 14 days after FTAI, respectively. Treatment with eCG increased ovulation rate [65.2% (15/23) vs. 30.4% (7/23); P=0.018], ovulatory follicle diameter (14.5±0.4 vs. 13.1±0.7mm, mean±SEM; P=0.081), CL area from 6 to 14 days after FTAI (344.3±25.1 vs. 274.2±23.9mm(2); P=0.045) and mean serum progesterone concentrations from FTAI to 14 days later (3.0±0.2 vs. 1.8±0.2ng/ml; P=0.001), in comparison with control cows. In conclusion, the addition of eCG to a progesterone and estradiol' based treatment for FTAI improves ovulation rate and luteal function in anestrous cows. These findings have implications in order to increase pregnancy rates in FTAI treatments in Bos taurus beef cattle.


Asunto(s)
Bovinos/fisiología , Gonadotropina Coriónica/farmacología , Cuerpo Lúteo/efectos de los fármacos , Estradiol/farmacología , Ovulación/efectos de los fármacos , Progesterona/farmacología , Animales , Cloprostenol/administración & dosificación , Cloprostenol/farmacología , Esquema de Medicación , Estradiol/administración & dosificación , Sincronización del Estro/métodos , Femenino , Fármacos para la Fertilidad Femenina/administración & dosificación , Fármacos para la Fertilidad Femenina/farmacología , Periodo Posparto , Embarazo , Progesterona/administración & dosificación
7.
Reprod Fertil Dev ; 22(1): 113-8, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20003852

RESUMEN

The present paper reviews the current state of knowledge in multiple ovulation and embryo transfer (MOET) technology in small ruminants, focusing on recently reported information. Major new findings are related to follicular wave patterns in small ruminants, the elucidation of follicular dominance and the integration of this information into ovarian superstimulatory treatment protocols. Follicular dynamics determine steroid and gonadotrophin secretion, follicular responses to FSH, ovulatory responses and embryo yield. Protocols that control follicular dominance have been designed to allow the initiation of superstimulation at the beginning of a follicular wave. New approaches consist of (1) synchronisation of ovulation for superstimulation during Wave 1 (i.e. Day 0 protocol), (2) pretreatment with a gonadotrophin-releasing hormone (GnRH) antagonist from 10 days prior to FSH treatment to avoid follicular dominance and (3) progesterone-oestradiol cotreatment to synchronise follicle wave emergence. These protocols provide a homogeneous pool of small follicles that are gonadotrophin responsive, enhancing the superovulatory response and embryo yield with a reduction in the incidence of unovulated follicles and early regression of corpora lutea. In addition, the rate of fertilisation failure has been reduced by using an inducer of ovulation (i.e. GnRH) associated with intrauterine insemination. In summary, the application of recently acquired knowledge has resulted in relevant improvements in MOET programmes in small ruminants.


Asunto(s)
Transferencia de Embrión/veterinaria , Cabras/embriología , Ovinos/embriología , Superovulación , Animales , Cruzamiento/métodos , Transferencia de Embrión/métodos , Sincronización del Estro/métodos , Femenino , Hormona Folículo Estimulante/farmacología , Hormona Liberadora de Gonadotropina/farmacología , Folículo Ovárico/efectos de los fármacos , Superovulación/efectos de los fármacos
9.
Theriogenology ; 52(3): 399-411, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10734375

RESUMEN

Ovarian changes determined by daily transrectal ultrasonic scanning, and its correlation with serum progesterone (P4) and estradiol (E2) concentrations were studied in seven cyclic Saanen goats. Estrous cycles were synchronized with 2 injections of a PGF2 alpha analogue 9 d apart. All follicles > or = 2 mm in diameter and CL were measured each day. One goat showed a longer interestrous interval, associated with development of a cystic-luteinized structure. The mean interovulatory interval for the other 6 goats was 20.8 +/- 0.4 d. The incidence of goats with 4, 3, and 2 follicular waves was 3, 1 and 2 respectively; follicular waves emerged on Days 0.5 +/- 0.6, 7.2 +/- 0.7, 10.7 +/- 0.5 and 13.7 +/- 0.8 for Wave 1, 2, 3 and the Ovulatory wave, respectively. The largest follicle of Wave 2 was smaller (4.9 +/- 0.1 mm) than the largest follicles of Wave 3 (6.2 +/- 0.1 mm; P < or = 0.01) and of the Ovulatory wave (7.0 +/- 0.5 mm; P < or = 0.01), and tended to be smaller than the largest follicle of Wave 1 (6.3 +/- 0.6 mm; P < or = 0.09). Interval between emergence of Wave 1 and Wave 2 was longer than interval between emergence of Wave 2 and Wave 3 (7.3 +/- 0.9 d vs 4.0 +/- 0.4 d; P < or = 0.01), and between Wave 3 and the Ovulatory wave (3.8 +/- 1.1 d; P < or = 0.05). Two days before ovulation, the diameter of the ovulatory follicle was larger (P < or = 0.01) than the first subordinate follicle. Serum E2 concentrations increased from the day of ovulation (2.7 +/- 0.3 pg/mL) to Day 2 (7.6 +/- 0.9 pg/mL; P < or = 0.01), associated with the early-mid growing phase of the largest follicle of Wave 1, and then decreased to basal levels on Day 5 (P < or = 0.01) and peaked again (16.5 +/- 2.4 pg/mL) 2 d before ovulation. The CL were detected ultrasonically on Day 3 post ovulation and attained a mean maximum diameter of 13.5 +/- 0.8 mm between Days 8 and 14. The following characteristics were observed: 1) ovarian follicular development in goats is wave-like; 2) increased P4 concentrations may be promoting follicular wave turnover; 3) it is suggested that the presence of follicular dominance and the production of E2 are different among waves. While in Wave 1 and in the Ovulatory wave, follicular dominance is present and production of E2 is consistent, no changes in serum E2 concentrations were found in other stages of the interovulatory interval. In the intervening waves, no indicators of follicular dominance could be firmly documented.


Asunto(s)
Estradiol/sangre , Estro/fisiología , Ovario/fisiología , Progesterona/sangre , Animales , Anovulación , Estro/sangre , Femenino , Cabras , Folículo Ovárico/citología , Folículo Ovárico/fisiología , Ovario/diagnóstico por imagen , Ovulación , Ultrasonografía
10.
Theriogenology ; 43(2): 465-72, 1995 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-16727638

RESUMEN

Superovulatory response to conventional treatment with eCG (1200 IU) and progestagen sponges (MAP, n = 9; FGA, n = 9; or controls without sponge, n = 6) was studied in Corriedale anestrous ewes. The follicular population just before the administration of eCG and the total ovarian response (large anovulatory follicles plus normal CL and prematurely regressing CL) to treatment were determined after laparotomy. Pretreatment with progestagen did not modify the number or class of follicles greater than 1 mm observed on the ovarian surface at the time of eCG administration (19 +/- 2.2 follicles vs 19 +/- 2.9 follicles, for pooled progestagen-treated groups and control groups, respectively; mean +/- SEM) but significantly decreased the number of large anovulatory follicles (4.7 +/- 1.0 vs 10.2 +/- 2.6; P < or = 0.01) observed following treatment. Progestagen-treated animals were classified according to the presence (n = 13) or absence (n = 5) of a large follicle (LF: > or = 4 mm diameter) on the ovarian surface at the time of eCG treatment; a qualitatively better superovulatory response was observed in ewes without large follicle (large anovulatory follicles: 1.6 +/- 0.7 vs 5.8 +/- 1.3, P < or = 0.05; normal CL: 7.0 +/- 1.4 vs 3.8 +/- 1.0, P < or = 0.1; normal CL/total ovarian response: 78.7 +/- 10.1 % vs 34.9 +/- 8.2 %, P < or = 0.01; for ewes without LF and ewes with 1 to 2 LF respectively). No differences were observed in the individual ovulatory response when comparing ovaries ipsilateral or contralateral to LF in a same animal, indicating that the effect of LF on the superovulatory response would be fundamentally systemic. This work shows that, similar to what occurs in cows, the presence of a large follicle at the time of gonadotropin administration decreases the superovulatory response in anestrous ewes.

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