RESUMO
Scaphanocephalus is a small trematode genus belonging to the family Opistorchiidae. The genus currently contains only three species associated with marine fish as intermediate hosts and fish-eating birds as definitive hosts. Here, specimens of Scaphanocephalus were collected from the Osprey, Pandion haliaetus, and the White mullet, Mugil curema in the Yucatán Peninsula, Mexico. We report for the first-time DNA sequences of adult specimens of Scaphanocephalus, particularly S. expansus, as well as a sequence of a different species sampled as metacercaria. Morphological comparisons of Scaphanocephalus expansus confirmed the identity of the adult specimens, with minor morphological variations; Scanning electron photomicrographs were included, and the species was re-described. Phylogenetic analysis based on 28S rDNA sequences showed that Scaphanocephalus is monophyletic within Opisthorchiidae and consists of three independent lineages. Sequences of adults are identical to those of S. expansus. Instead, the sequence of the metacercaria sampled from the mesentery of Mugil curema nested with specimens reported as Scaphanocephalus sp. from a labrid fish in the Mediterranean Sea, herein named it as Scaphanocephalus sp. 2.
Assuntos
Falconiformes , Doenças dos Peixes , Heterophyidae , Smegmamorpha , Trematódeos , Infecções por Trematódeos , Animais , México , Filogenia , DNA de Helmintos/genética , Heterophyidae/genética , Peixes , Metacercárias , Infecções por Trematódeos/veterináriaRESUMO
Members of the genus Strigea Abildgaard, 1790 are endoparasites of birds distributed worldwide. Adults of an undescribed species of the genus Strigea were collected from the intestines of two hawk species (Rupornis magnirostris and Accipiter coperii). Other species identified as Parastrigea macrobursa that were described in Argentina were also recovered from two hawk species (Buteogallus urubitinga and Buteogallus anthracinus) in three localities along the coasts of Mexico. Specimens of the two species were sequenced for three molecular markers, the internal transcribed spacers locus (ITS1-5.8S rDNA- ITS2) and the domains D1-D3 from the large subunit from nuclear ribosomal DNA and the cytochrome c oxidase subunit 1 from mitochondrial DNA. The newly sequenced specimens were aligned with other strigeids sequences downloaded from GenBank. Maximum likelihood and Bayesian analyses inferred with each molecular marker revealed that our specimens of Strigea sp. formed an independent lineage, which is recognized herein as a new species, Strigea magnirostris n. sp., representing the first species in Mexico and the 16th in the Neotropical region. Morphologically, the new species is distinguished from other congeneric species from the Americas by having an oral sucker with several papillae around it, well-developed pseudosuckers (118-248 µm), a tegument covered with tiny spines, a larger cone genital (193-361 × 296-637) and a larger copulatory bursa (247-531 × 468-784). Our phylogenetic analyses revealed that P. macrobursa is not closely related to other members of the genus Parastrigea and is nested within Strigea, suggesting that P. macrobursa should be transferred to Strigea to form Strigea macrobursa n. comb., expanding its distribution range from Mexico to Argentina. Finally, the analyses also revealed that the taxonomy and systematics of Strigea should be re-evaluated, combining morphological and molecular characteristics.
Assuntos
Aves Predatórias , Trematódeos , Animais , Filogenia , Teorema de Bayes , Aves , DNA Ribossômico/genética , México , DNA de Helmintos/genéticaRESUMO
Adult specimens of Andracantha gravida (Alegret, 1941) were recorded from the intestines of the double-crested cormorant Nannopterum auritus (Lesson) (type host) and brown pelican Pelecanus occidentalis L. in two localities from Mexico: Celestún, Yucatan (south-eastern) and Punta Piedra, Tamaulipas (north-eastern). The specimens of A. gravida are morphologically characterized by having a pipe-shaped body without swellings, the absence of small trunk spines between the two fields of spines on the foretrunk and a cylindrical proboscis with 14-16 rows of 10-12 hooks per row. Newly generated partial sequences of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were generated from adult isolates of A. gravida from Mexico and compared with one sequence of A. gravida and with sequences of other polymorphid acanthocephalans available in GenBank. Phylogenetic analyses based on maximum likelihood and Bayesian inference methods of the cox1 dataset placed all the species of Andracantha in a single clade, with weak support. The analyses of the cox1 dataset placed Andracantha sigma Presswell, García-Varela & Smales, , as sister to the clade formed by A. gravida, Andracantha phalacrocoracis (Yamaguti, 1939), Andracantha leucocarboi Presswell, García-Varela & Smales, and an unidentified species of Andracantha from Japan. The newly generated cox1 sequences of A. gravida from piscivorous birds of Mexico formed a strongly supported clade with the published sequence of A. gravida from the double-crested cormorant from the south-eastern coast of Mexico. The intraspecific genetic divergence among isolates identified as A. gravida ranged from 0.0% to 2.2%. A cox1 haplotype network inferred with 14 sequences revealed the presence of nine haplotypes, two of which were shared between the populations of piscivorous birds from the north-eastern and south-eastern coasts of Mexico and seven of which were unique. The fixation index between the populations from north-eastern and south-eastern Mexico was low (0.06949), which suggests genetic flow. This can be explained by the migration patterns of the brown pelican and the double-crested cormorant along the coasts of the Gulf of Mexico.
Assuntos
Acantocéfalos , Animais , Filogenia , Golfo do México , Teorema de Bayes , Aves , MéxicoRESUMO
Members of Forticulcitinae Blasco-Costa, Balbuena, Kostadinova & Olson, 2009 include endoparasites of mullet fishes distributed worldwide. Adult specimens were collected from the intestines of white mullet (Mugil curema) and flathead grey mullet (Mugil cephalus) from five localities in the Gulf of Mexico and a single locality in Venezuela. Photogenophores were sequenced for two nuclear molecular markers, the large subunit (LSU) and second internal transcribed spacer (ITS2) of nuclear rDNA. The new sequences were aligned with other sequences downloaded from GenBank. The maximum likelihood and Bayesian inferences were deduced using the combined dataset (LSU + ITS2). The phylogenetic analyses revealed four new lineages belonging to Forticulcitinae. Three new species are described in the present study. Ekuarhuni mexicanus n. sp. can be differentiated from its congeneric species by presenting a longer hermaphroditic sac length (136-180 µm) and a wider testis (91-123 µm). Forticulcita macropharyngis n. sp. and Forticulcita venezuelensis n. sp. are the 8th and 9th species described in Forticulcita. Both species belong to the diminutive morphotype of Forticulcita. Forticulcita macropharyngis n. sp. can be morphologically distinguished from the other congeneric species by the presence of a massive and muscular pharynx (46-110 µm long, 74-106 µm wide). Forticulcita venezuelensis n. sp. is the second species of the studied genus recorded in South America and can be differentiated from congeneric species by possessing the largest testis (138-201 µm long, 83-100 µm wide). Finally, the fourth lineage corresponds to Overstreetoides Andrade-Gómez & García-Varela, 2021; however, few specimens of this lineage were collected, precluding any description of the species. In addition, a key is proposed for differentiating the genera and species of Forticulcitinae.
Assuntos
Filogenia , Smegmamorpha/parasitologia , Trematódeos/classificação , América , Animais , DNA de Helmintos/genética , DNA Ribossômico/genética , Golfo do México , Especificidade da Espécie , Trematódeos/anatomia & histologia , Trematódeos/genética , VenezuelaRESUMO
A new species of the genus Lyperosomum Looss, 1899, from the intestine of the golden-fronted woodpecker (Melanerpes aurifrons) from northern Mexico is described. Lyperosomum cuauhxinqui sp. n. is morphologically distinguished from other congeneric species from the Americas by a higher oral/ventral sucker ratio and its body length and width. The sequences of domains D1-D3 of the large subunit (LSU) of nuclear ribosomal DNA and cytochrome c oxidase subunit 1 (cox 1) from the mitochondrial DNA of the new species were obtained and compared with available sequences from GenBank. The genetic divergence estimated between the new species and other congeneric species ranged from 2 to 6% and 13.4 to 17.3% for LSU and cox 1, respectively. Phylogenetic analyses based on the two (LSU and cox 1) molecular markers consistently showed that L. cuauhxinqui sp. n. was nested within the genus Lyperosomum, with strong bootstrap support (100%) and Bayesian posterior probabilities (1.0). In particular, the LSU tree indicated that the sequence of the new species is closely related to sequences from Zonorchis alveyi, Zonorchis delectans and Zonorchis sp. from Central America, suggesting that these sequences should be transferred to the genus Lyperosomum. The new species represents the first record from Mexico and the fifth species identified in the Americas. Our study also revealed that the taxonomy of the genus Lyperosomum should be re-examined by combining molecular, morphological and ecological characteristics.
Assuntos
Aves/parasitologia , Dicrocoeliidae/anatomia & histologia , Dicrocoeliidae/classificação , Filogenia , Animais , Teorema de Bayes , América Central , DNA de Helmintos/genética , DNA Mitocondrial/genética , DNA Ribossômico/genética , Feminino , Variação Genética , México , Análise de Sequência de DNARESUMO
The centromere appears as a single constriction at mitotic metaphase in most eukaryotic chromosomes. Holokinetic chromosomes are the exception to this rule because they do not show any centromeric constrictions. Holokinetic chromosomes are usually forgotten in most reviews about centromeres, despite their presence in a number of animal and plant species. They are generally linked to very intriguing and unusual mechanisms of mitosis and meiosis. Holokinetic chromosomes differ from monocentric chromosomes not only in the extension of the kinetochore plate, but also in many other peculiar karyological features, which could be understood as the 'holokinetic syndrome' that is reviewed in detail. Together with holokinetic chromosomes we review neocentromeric activity, a similarly intriguing case of regions able to pull chromosomes towards the poles without showing the main components reported to be essential to centromeric function. A neocentromere is a chromosomal region different from the true centromere in structure, DNA sequence and location, but is able to lead chromosomes to the cell poles in special circumstances. Neocentromeres have been reported in plants and animals showing different features. Both in humans and Drosophila, neocentric activity appears in somatic cells with defective chromosomes lacking a functional centromere. In most cases in plants, neocentromeres appear in chromosomes which have normal centromeres, but are active only during meiosis. Because of examples such as spontaneous or induced neocentromeres and holokinetic chromosomes, it is becoming less surprising that different structures and DNA sequences of centromeres appear in evolution.
Assuntos
Centrômero/genética , Centrômero/fisiologia , Cromossomos de Plantas/genética , Cromossomos de Plantas/fisiologia , Animais , Segregação de Cromossomos/genética , Segregação de Cromossomos/fisiologia , Cromossomos/genética , Cromossomos/fisiologia , Cyperaceae/genética , Humanos , Meiose/genética , Meiose/fisiologia , Mitose/genética , Mitose/fisiologia , Secale/genética , Zea mays/genéticaRESUMO
OBJECTIVE: To describe the response to exercise of normal subjects and patients with chronic obstructive pulmonary disease (COPD) in Bogota, Colombia (altitude: 2640 m; atmospheric pressure: 560 mm Hg) and compare it with data published on COPD patients at sea level. Healthy people increase their minute ventilation to attenuate hypoxemia (PaCO2: 30 mm Hg; PaO2: 63 mm Hg). MATERIAL AND METHOD: A descriptive study was carried out on healthy subjects and COPD patients. Exercise limitation was determined by an incremental test on a cycle ergometer. RESULTS: The study enrolled 16 healthy subjects and 25 COPD patients (forced expiratory volume in 1 second: 43.3% [SD 13%]). Minute ventilation at rest was greater in COPD patients compared with healthy subjects, it was not adequately sustained during exercise, and there was a reduction in peak oxygen uptake (53.0% [15%]). At peak exercise, inspiratory capacity decreased (-0.62 [0.34] L), the ratio of minute ventilation to maximal voluntary ventilation increased, and severe hypoxemia occurred (PaO2: 49.9 [9.9] mm Hg). There was significant correlation between hypoxemia and the percentage of predicted peak oxygen uptake (r=0.60), leg fatigue (r=-0.62), percentage of predicted peak inspiratory capacity (r=0.61), and the percentage of predicted peak tidal volume (r=0.49). Minute ventilation at rest was shown to be higher, there was a greater reduction in the inspiratory capacity during exercise, and hypoxemia was more severe at rest and during exercise for patients with COPD in Bogota, compared with those at sea level. CONCLUSIONS: Patients with COPD living in Bogota were shown to have lower tolerance to exercise evidenced by ventilatory limitation and severe hypoxemia. Increased minute ventilation at rest, greater reduction in inspiratory capacity, and severity of hypoxemia during exercise were the main differences between COPD in Bogota and at sea level.
Assuntos
Altitude , Exercício Físico/fisiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Ventilação Pulmonar/fisiologia , Gasometria , Colômbia , Teste de Esforço , Feminino , Humanos , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Fenômenos Fisiológicos Respiratórios , Descanso , EspirometriaRESUMO
OBJECTIVE: To analyze the efficacy of a combined approach using ERCP plus laparoscopic cholecystectomy in the treatment of gallstones associated to benign common bile duct obstruction. DESIGN: Prospective study. SETTING: Tertiary-care medical center. PATIENTS: From a total of 270 laparoscopic cholecystectomies performed between October 1991 and January 1994, a group of 25 patients in whom preoperative ERCP was performed to rule out bile duct obstruction was selected for analysis. RESULTS: Choledocholithiasis was documented in nine patients (36%). In eight of them, stones were retrieved by ERCP. The diagnosis of odditis was established in five patients and a papilotomy was performed. The entire bile duct was normal in 11 cases. All patients in whom the common bile duct was normal, or cleared endoscopically, underwent laparoscopic cholecystectomy uneventfully. There was one complication of papilotomy. Duodenal perforation occurred in one patient who ultimately died. CONCLUSION: The combined approach using ERCP followed by laparoscopic cholecystectomy seems to be adequate for the treatment of gallstones associated to bile duct obstruction.
Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Colecistectomia Laparoscópica/métodos , Colelitíase/cirurgia , Cálculos Biliares/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Fosfatase Alcalina/sangue , Ampola Hepatopancreática/cirurgia , Bilirrubina/sangue , Biomarcadores/sangue , Colangite/complicações , Colangite/diagnóstico , Colangite/cirurgia , Colecistectomia Laparoscópica/efeitos adversos , Colelitíase/complicações , Duodeno/lesões , Feminino , Cálculos Biliares/complicações , Cálculos Biliares/diagnóstico por imagem , Cálculos Biliares/cirurgia , Humanos , Perfuração Intestinal/etiologia , Complicações Intraoperatórias , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Esfíncter da Ampola Hepatopancreática/cirurgia , UltrassonografiaRESUMO
Cystic tumors of the pancreas are rare, although their detection has become more frequent with the advent of imaging techniques. In most cases, surgical exploration and often resection of the cystic neoplasm is necessary for establishing a definitive diagnosis; resection remains the treatment of choice. This paper describes three patients who underwent surgery because of cystic tumors of the pancreas. Abdominal pain was the main clinical manifestation; abdominal CT showed the cystic tumor in all three cases. Surgical exploration and resection was successfully accomplished in all. The definitive histological diagnoses were serous cystadenoma, multicystic hamartoma, and choriocarcinoma metastatic to the head of the pancreas. To our knowledge, the last two are the first ones with such diseases reported in the literature.
Assuntos
Coriocarcinoma/secundário , Cistadenoma Seroso/diagnóstico , Hamartoma/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico , Dor Abdominal/etiologia , Adulto , Coriocarcinoma/diagnóstico , Coriocarcinoma/patologia , Cistadenoma Seroso/patologia , Neoplasias do Endométrio/patologia , Feminino , Hamartoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/secundário , Tomografia Computadorizada por Raios XRESUMO
This paper reports the experience obtained in the last 8 years with an instrument (articulated rotative brush) that allows access to the entire endometrial surface, obtaining material for both histological and cytological study. The latter has the advantage of reducing the number of cases in which insufficient material frustrates endometrial assessment. In addition to the overall experience gained with this instrument, the proportion of agreement with anatomo-pathological diagnosis after hysterectomy in 61 patients was high (96%) and the unweighted kappa statistic (0.862) indicated very good accordance between these techniques. Comparison between the present method and hysteroscopic observations in 84 patients with perimenopausal bleeding revealed a general conformity of 0.65 and an unweighted kappa statistic of 0.368 (fair agreement). In a group of 72 cases with postmenopausal bleeding a general conformity value of 0.92 was obtained, with an unweighted kappa statistic of 0.84 (very good agreement). In 90% of the cases the procedure was well accepted. In 57.3% of the cases, no difficulties were encountered using the brushing technique; in 25.9% slight dilatation was deemed necessary, whereas in 16.8% technical difficulties could not be overcome and general anesthesia was indicated. A total of 769 outpatients were investigated, 75.3% of which had normal endometria, 12.7% benign hyperplasias, 2.6% precursor lesions, 1.7% suspect carcinoma, and 4.2% carcinomas. Insufficient material for diagnosis occurred in 3.5% of cases tested. The combined cytohistological and hysteroscopic assessment of the endometrium provides satisfactory results in the etiological diagnosis of peri and postmenopausal bleeding, and in the follow up of patients undergoing hormonal replacement therapy (HRT).
Assuntos
Biópsia/instrumentação , Climatério/fisiologia , Endométrio/patologia , Histeroscópios , Hemorragia Uterina/patologia , Adulto , Idoso , Assistência Ambulatorial , Desenho de Equipamento , Feminino , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos TestesRESUMO
Have been studied a 47 years old woman who present a facial deformity related to right hemifacial fat atrophy in dermal and subcutaneous tissues. This clinic finding with others from radiologic and electromyographic explorations are suggesting of Romberg's syndrome. We have done the more important differential diagnosis and reviewed the present surgical techniques for treatment.
Assuntos
Hemiatrofia Facial/diagnóstico , Diagnóstico Diferencial , Eletromiografia , Hemiatrofia Facial/cirurgia , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
Four phenotypic cytologic parameters (koilocytotic changes, binucleation, multinucleation and the presence of metaplastic dysplastic cells) were evaluated in the initial cervical smears from 89 women who presented with slight or moderate dysplastic changes and had an adequate follow-up. The cases were divided in two groups according to their evolution: the 51 cases constituting group I showed persistence or progression of the lesions while the 38 cases in group II showed regression. Koilocytosis in 40% or more of the cells in a smear proved to have the greatest predictive value as an indicator of a lesion with less risk of progression. Multinucleation may have a similar value, but to a lesser degree. Binucleation and metaplastic dysplastic cells showed no statistical differences between persistence cases and regression cases. A fifth parameter, positivity to human papillomavirus capsid antigen by the immunoperoxidase technique, doubled its frequency in the regression group. The evaluation of these variables may provide a means of assessing the evolutionary potential of precursor cervical lesions, based on these lesions' cytologic phenotypic profiles.