313 resultados para Follicles


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Chronic sclerosing sialadenitis is an uncommon cause of salivary gland enlargement mainly occurring in the fifth and seventh decade of life. In the Western population, chronic sclerosing sialadenitis has been characterized as an IgG4-related disease. Although rare, this lesion occurs in children. To increase awareness about this entity in the pediatric age group, we report the case of an 11-year-old boy with a hard, 4.0-cm circumscribed mass in the right submandibular gland. Histologically there was marked distortion of the gland architecture by a dense lymphocytic infiltrate and extensive fibrosis with septa that crossed and distorted the gland, leaving atrophic acini and dilated, irregular ducts. The lymphoid infiltrate formed multiple follicles with active germinal centers, numerous plasma cells, and areas with diffuse arrangement. Immunophenotyping showed abundant CD20- and CD3-positive lymphocytes; cytokeratin AE1/AE3 highlighted the distorted architectural pattern; IgG staining showed large numbers of positive cells infiltrating the interstitium and surrounding the atrophic acini and ducts. IgG4 staining revealed a large proportion of positive infiltrating elements. Kuttner tumor belongs to the group of IgG4-related sclerosing diseases. The differential diagnosis includes pleomorphic adenoma and other salivary gland neoplasms. Its recognition in children is important clinically because this entity is amenable to steroid treatment, and additional work up and follow up is warranted to stave off other IgG4-related diseases/complications.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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In Neoponera villosa ants, we found ovaries of the polytrophic meroistic type which is characterized by the presence of nurse cells forming together with the oocyte, the so-called follicles. The nurse cells have the primary function of supplying the oocyte with RNA, but they contribute to the supply of other elements such as glycogen. With the objetive of detecting the presence of this substance in the ovarioles of workers and queens of N. viillosa ants the ovaries were removed and processed according to electron microscopy technic for glycogen detection. Glycogen is a common element in insect oocytes and is abundantly distributed in the cytoplasm of N. villosa workers and queens. However, in ovarian follicles it can only be detected at stages II and III of development. Glycogen synthesis probably occurs predominantly in nurse cells which transfer it into the oocyte through the nourish pore. This process requires high energy expenditure that justify the large numbers of mitochondria associated with glycogen in the nurse cell cytoplasm. The amount of glycogen in the nurse cells of queens is slightly greater than workers.

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The effects of several doses of progesterone on FSH and LH concentrations were used to study the role of the gonadotropins on deviation in growth rates of the two largest follicles during the establishment of follicle dominance. Progesterone was given to pony mares at a daily dose rate of 0 mg (controls), 30 mg (low dose), 100 mg (intermediate dose), and 300 mg (high dose). All follicles ≥ 6 mm were ablated at Day 10 (Day 0 = ovulation) to initiate a new follicular wave; prostaglandin F(2α) was given to induce luteolysis, and progesterone was given from Days 10 to 24. The low dose did not significantly alter any of the ovarian or gonadotropin end points. The high dose reduced (P < 0.05) the ablation-induced FSH concentrations on Day 11. Maximum diameter of the largest follicle (17.2 ± 0.6 mm) and the second- largest follicle (15.5 ± 0.9 mm) in the high-dose group was less (P < 0.04) than the diameter of the second-largest follicle in the controls (20.0 ± 1.0 mm) at the beginning of deviation (Day 16.7 ± 0.4). Thus, the growth of the two largest follicles was reduced by the high dose, presumably through depression of FSH, so that the follicles did not attain a diameter characteristic of deviation in the controls. The intermediate dose did not affect FSH concentrations. However, the LH concentrations increased in the control, low, and intermediate groups, but then decreased (P < 0.05) in the intermediate group to pretreatment levels. The LH decrease in the intermediate group occurred 2 days before deviation in the controls. The maximum diameter of the largest follicle was less (P < 0.0001) in the intermediate group (27.3 ± 1.8 mm) than in the controls (38.9 ± 1.5 mm), but the maximum diameter of the second-largest follicle was not different between the two groups (19.0 ± 1.1 vs. 20.3 ± 1.0 mm). Thus, the onset of deviation, as assessed by the second-largest follicle, was not delayed by the decrease in LH. Diameter of the largest follicle by Day 18 in the intermediate group (23.1 ± 1.6 mm) was less (P < 0.05) than in the controls (28.0 ± 1.0 mm). These results suggest that circulating LH was not involved in the initiation of dominance (inhibition of other follicles by the largest follicle) but was required for the continued growth of the largest follicle after or concurrently with its initial expression of dominance.

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The effect of altered LH concentrations on the deviation in growth rates between the 2 largest follicles was studied in pony mares. The progestational phase was shortened by administration of PGF2α on Day 10 (Day 0=ovulation; n=9) or lengthened by daily administration of 100 mg of progesterone on Days 10 to 30 (n=11; controls, n=10). All follicles ≥5 mm were ablated on Day 10 in all groups to initiate a new follicular wave. The interovulatory interval was not altered by the PGF2α treatment despite a 4-day earlier decrease in progesterone concentrations. Time required for growth of the follicles of the new wave apparently delayed the interval to ovulation after luteolysis. The FSH concentrations of the first post-ablation FSH surge were not different among groups. A second FSH surge with an associated follicular wave began by Day 22 in 7 of 11 mares in the progesterone group and in 0 of 19 mares in the other groups, indicating reduced functional competence of the largest follicle. A prolonged elevation in LH concentrations began on the mean day of wave emergence (Day 11) in the prostaglandin group (19.2 ± 2.2 vs 9.0 ± 0.7 ng/mL in controls; P<0.05), an average of 4 d before an increase in the controls. Concentrations of LH in the progesterone group initially increased until Day 14 and then decreased so that by Day 18 the concentrations were lower (P<0.05) than in the control group (12.9 ± 1.6 vs 20.2 ± 2.6 ng/mL). Neither the early and prolonged increase nor the early decrease in LH concentrations altered the growth profile of the second-largest follicle, suggesting that LH was not involved in the initiation of deviation. However, the early decrease in LH concentrations in the progesterone group was followed by a smaller (P<0.05) diameter of the largest follicle by Day 20 (26.9 ± 1.7 mm) than the controls (30.3 ± 1.7 mm), suggesting that LH was necessary for continued growth of the largest follicle after deviation. (C) 2000 by Elsevier B.V.

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Inhibins are dimeric glycoproteins composed of an α-subunit and a βA-subunit (inhibin A) or βB-subunit (inhibin B), which inhibits pituitary gonadotropin secretion of FSH. The inhibin B is a product of the cohort of antral follicles. The ovarian follicle number decrease steadily as a function of increasing age, with consequent falls in the levels of inhibin B and increase of FSH levels. It is sufficient to maintain ovulatory function and continued secretion of estradiol. Elevated FSH levels seem to occur late in the sequence of events associated with ovarian failure. The inhibin B, produced by granulosa cells, is the earliest marker of the decline in ovarian follicular reserve across reproductive aging.

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In Anastrepha sp.2 aff. fraterculus, the egg-cell harbours a large population of endosymbionts. The bacteria were identified as belonging to genus Wolbachia by PCR assay using primers of the ftsZ gene followed by sequencing of the amplified band. Newly deposited eggs stained in toto by Hoechst show that the bacteria are unevenly dispersed throughout the egg-cell, with a higher accumulation at the posterior pole, and that the degree of infestation varies from egg to egg. Analysis by transmission electron microscopy shows that bacteria are present in the female germ line of embryonic and larval stages, as well as in the different cell types of the ovaries at the adult stage. Mature ova within the follicles harbour a large population of the symbionts. The results indicate the existence of a transovarian transmission of the endosymbionts in this fly.

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The present results show that in the ovarioles of a newly emerged (0 day) queen of A. mellifera only two regions may be distinguished: a proximal, short germarium and a very long distal, terminal filament. As the queen matures and gets ready for the nupcial flight, the germarium increases in lenght, advancing towered the distal end, as the terminal filament shortens. The ovarioles of queens ready to mate (6 to 8 days old) have, already one or two ovarian follicles, i.e. a very short proximal vitellarium, but a real vitellogenesis only starts after the fecundation. If the queen does not mate the ovarioles structure is disrupted (12-16 days old). In mated queen eggs the ovarioles present three differentiated regions, from the apice to the basis: a short terminal filament, a medium size germarium, and a very long basal vitellarium. As the eggs are laid, the emptied follicle collapses, degenerates and produces a corpus luteum.

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The poisonous plant Baccharis coridifotia causes necrosis in lymphoid tissues and the gastrointestinal tract of cattle, horses, sheep and rabbits. An experimental poisoning of mice was undertaken to establish an experimental model in a laboratory animal specie. A single 5 to 8-g/kg dose of a suspension of the plant was administered by gavage to II mice. To 3 other control mice, the same volume of water was administered. Plant-dosed mice manifested clinical effects after 12 h: tachipnea, trembles, dehydration and prostration. Most of the dosed mice died 14 to 33 h after plant administration-3 survived for 12 d. Six mice had remarkable necrosis of the germinative center of secondary follicles in lymph nodes and spleen; 3 mice had necrosis of lymphoid tissues in intestine and thymus. Mice reproduce most of the lesions observed in naturally poisoned cattle and the use of this specie as an experimental model is valid.

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In the present study, seventy-two adult rats (Rattus norvegicus albinus) aged three months were used. The animals were divided into two groups (control and alcoholic). The control group received a solid diet (Purina rat chow) and tap water ad libitum. The alcoholic group received the same solid diet and sugar-cane liquid (trade 51, 41° Gay Lussac - GL) diluted 30° GL. At the end or 90, 180 and 270 days of treatment, ten rats of each group were anaesthetized with ethyl ether and sacrificed. The ovaries were collected, fixed, included and submitted to analysis by both light and electron microscopy. The alcoholic group showed increase in the number of corpora lutea at both 180 and 270 days of treatment, atresic follicles at 270 days of treatment, decreased diameter of corpora lutea at 180 and 270 days of treatment, the granulosa layer of the antral follicles at 180 days of treatment, and gradual regression of the theca antral follicles. Furthermore, an increase in diameter and posterior regression of the antral follicle were observed, as well as vacuolation, increased lipid droplets in the granulosa cell at 90 days and in the theca at 180 and 270 days of treatment and gradually in the interstitial cell. The rats showed ovarian alterations after ingestion of alcohol. There was a correlation between exposure time to the drug and the injury observed.

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Superovulation would potentially increase the efficiency and decrease the cost of embryo transfer by increasing embryo collection rates. Other potential clinical applications include improving pregnancy rates from frozen semen, treatment of subfertility in stallions and mares, and induction of ovulation in transitional mares. The objective of this study was to evaluate the efficacy of purified equine follicle stimulating hormone (eFSH; Bioniche Animal Health USA, Inc., Athens, GA) in inducing superovulation in cycling mares. In the first experiment, 49 normal, cycling mares were used in a study at Colorado State University. Mares were assigned to 1 of 3 groups: group 1, controls (n = 29) and groups 2 and 3, eFSH-treated (n = 10/group). Treated mares were administered 25 mg of eFSH twice daily beginning 5 or 6 days after ovulation (group 2). Mares received 250 (of cloprostenol on the second day of eFSH treatment. Administration of eFSH continued until the majority of follicles reached a diameter of 35 mm, at which time a deslorelin implant was administered. Group 3 mares (n = 10) received 12 mg of eFSH twice daily starting on day 5 or 6. The treatment regimen was identical to that of group 2. Mares in all 3 groups were bred with semen from 1 of 4 stallions. Pregnancy status was determined at 14 to 16 days after ovulation. In experiment 2, 16 light-horse mares were used during the physiologic breeding season in Brazil. On the first cycle, mares served as controls, and on the second cycle, mares were administered 12 mg of eFSH twice daily until a majority of follicles were 35 mm in diameter, at which time human chorionic gonadotropin (hCG) was administered. Mares were inseminated on both cycles, and embryo collection attempts were performed 7 or 8 days after ovulation. Mares treated with 25 mg of eFSH developed a greater number of follicles (35 mm) and ovulated a greater number of follicles than control mares. However, the number of pregnancies obtained per mare was not different between control mares and those receiving 25 mg of eFSH twice daily. Mares treated with 12 mg of eFSH and administered either hCG or deslorelin also developed more follicles than untreated controls. Mares receiving eFSH followed by hCG ovulated a greater number of follicles than control mares, whereas the number of ovulations from mares receiving eFSH followed by deslorelin was similar to that of control mares. Pregnancy rate for mares induced to ovulate with hCG was higher than that of control mares, whereas the pregnancy rate for eFSH-treated mares induced to ovulate with deslorelin did not differ from that of the controls. Overall, 80% of mares administered eFSH had multiple ovulations compared with 10.3% of the control mares. In experiment 2, the number of large follicles was greater in the eFSH-treated cycle than the previous untreated cycle. In addition, the number of ovulations during the cycle in which mares were treated with eFSH was greater (3.6) than for the control cycle (1.0). The average number of embryos recovered per mare for the eFSH cycle (1.9 ± 0.3) was greater than the embryo recovery rate for the control cycle (0.5 ± 0.3). In summary, the highest ovulation and the highest pregnancy and embryo recovery rates were obtained after administration of 12 mg of eFSH twice daily followed by 2500 IU of hCG. Superovulation with eFSH increased pregnancy rate and embryo recovery rate and, thus, the efficiency of the embryo transfer program.

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Cases of bovine demodicosis caused by Demodex bovis were reported in a Sindhi herd from December 1989 to January 1992. Both localized and generalized forms were diagnosed. This is the first report of the generalized form in Brazil. In the first two years, demodicosis was diagnosed only in cattle < 2 years old, whereas animals of all ages were positive in the last two years. Prevalence varied from 20.4% (11/54) to 53.1% (26/49) and 13.2% (12/91) to 14.8% (9/61) for cattle < 2 years old and > 2 years old, respectively. Clinical signs varied from a few small nodules to a thickened skin with soft large nodules in the localized and generalized forms, respectively. Main microscopic features of the nodules in the generalized form consisted of acanthosis with hyperqueratosis, chronic sebaceous adenitis, subcutaneous muscular necrosis, focal cellular degeneration of the epidermis basal layer and presence of large number of mites inside the lumen of dilated hair follicles. In addition, a chronic perifoliculitis was observed, characterized by lymphoplasmocytic infiltrate which also contained macrophages and neutrophils. It is suggested that poor nutrition and stress due to prolonged drought probably contributed to the increase of susceptibility of the herd to mite infestation.