Ultrastructure and development during meiosis and the tetrad period of sporogenesis in the leptosporangiate fern Alsophila setosa (Cyatheaceae) compared with corresponding stages in Psilotum nudum (Psilotaceae)
Gabarayeva N.I.,RAS Komarov Botanical Institute |
Grigorjeva V.V.,RAS Komarov Botanical Institute |
Marquez G.,La Plata University
Grana | Year: 2011
The pre-meiotic, meiotic and tetrad stages of development in microsporangia of Alsophila setosa were studied with particular emphasis on the early establishment of patterning in the microspore wall and the subsequent development of the sporoderm. The data obtained were compared with corresponding ontogenetic stages of Psilotum nudum. Tapetal behaviour was also examined. During the tetrad period, only one layer, a thin undulating sheet, appeared alongside the plasma membrane of the tetraspores, and this was evidently formed on a pre-patterned structure - a fibrillar layer, corresponding to a kind of primexine matrix. The early free microspores had a wavy plasma membrane with a parallel, sinusoidal, thin initial sporoderm layer. The proximal apertural fold was observed to be an extended outgrowth of this initial spore envelope. Sporoderm ontogeny during the tetrad period in Alsophila and Psilotum show some common points, but also fundamental differences, mainly in the relative timing of events: in Alsophila the end of the tetrad period is the starting point for exospore development, whereas in Psilotum the exospore is already complete at this stage. Considerable differences were also observed in the tapetum of the two species. © 2011 Collegium Palynologicum Scandinavicum.
Javier B.A.,La Plata University |
Laura R.M.,University of Buenos Aires |
Celeste S.,University of Buenos Aires |
Alcides T.,University of Buenos Aires
Asian Pacific Journal of Tropical Medicine | Year: 2010
Leishmaniasis is a parasitic infection caused by species leishmaniae, which can produce two types of manifestations: visceral and cutaneous. In south America cutaneous leishmaniasis is more common than visceral leishmaniasis. A case of primary cutaneous leishmaniasis from Bolivia is presented for its rarity. The patient of our case showed an ulcerated lesion of the knee. Montenegro's intradermal test was positive. Giemsa-stained touch preparation of the skin biopsy revealed amastigotes inside macrophages, consistent with leishmaniasis. The patient was treated with meglumine antimoniate intramuscular (20 mg of Sb+/kg/day) three weeks, with complete cicatrization of the lesion. © 2010 Hainan Medical College.
Lamberti Y.A.,La Plata University |
Hayes J.A.,La Plata University |
Perez Vidakovics M.L.,La Plata University |
Perez Vidakovics M.L.,Skane University Hospital |
And 2 more authors.
Infection and Immunity | Year: 2010
Although Bordetella pertussis has been observed to survive inside macrophages, its ability to resist or evade degradation in phagolysosomes has not been defined. We here investigated the trafficking of B. pertussis upon entry into human macrophages. During the first hours following phagocytosis, a high percentage of bacteria were destroyed within acidic compartments positive for the lysosome-associated membrane proteins (LAMP). However, roughly one-fourth of the bacteria taken up evade this initial killing event, remaining in nonacidic compartments. Forty-eight hours after infection, the number of intracellular bacteria per cell increased, suggesting that B. pertussis is capable of replicating in this type of compartment. Viable bacteria accumulated within phagosomal compartments positive for the early endosomal marker Rab5 but not the late endosomal marker LAMP. Moreover, B. pertussis-containing phagosomes acquired exogenously added transferrin, indicating that intracellular bacteria have access to extracellular components and essential nutrients via the host cell recycling pathway. Overall, these results suggest that B. pertussis survives and eventually replicates in compartments with characteristics of early endosomes, potentially contributing to its extraordinary ability to persist within hosts and populations. Copyright © 2010, American Society for Microbiology. All Rights Reserved.
Diaz A.A.,La Plata University |
Rodriguez E.M.,National University of Central Buenos Aires |
Escudero E.,La Plata University
Journal of Echocardiography | Year: 2010
Background: The ratio of transmitral peak E wave velocity to color flow propagation velocity (E/Vp index) has proved to be a significant predictor of prognosis in cardiac diseases with sinus rhythm. However, its usefulness in patients with atrial fibrillation (AF) and heart failure has not yet been established. The aim of this study was to determine the feasibility of using the E/Vp index for the prediction of mortality and heart failure hospitalization in this group. Methods: We studied 66 ambulatory patients with stable congestive heart failure (CHF) functional class I-III and AF. Patients were divided into group A and B according to an E/Vp index <1.5 and ≥1.5, respectively. Results: During follow-up (average 430 days) events were more common in group B (75 vs. 17%, log rank test; hazard ratio (HR) = 6.8). By means of multivariate logistic regression analysis, E/Vp proved to be an independent predictor of events (p = 0.0012). Conclusions: In our patients with stable CHF and AF the E/Vp index is a significant predictor of clinical outcome. © 2010 Japanese Society of Echocardiography.
Martino P.E.,La Plata University |
Arauz S.M.,La Plata University |
Anselmino F.,La Plata University |
Cisterna C.C.,National Institute of Technology |
And 3 more authors.
Journal of Zoo and Wildlife Medicine | Year: 2012
Information onreference blood values in the literature is lacking for many wild rodents. In this study, comprehensive reference intervals (RIs) for a wide range of analytes from 101 healthy free-ranging nutria were determined. Animals were captured in Buenos Aires, Argentina (37°50′S, 57°34′W), and southward (38°60′S, 58°23′W), encompassing major biotopes of agricultural pampas with dunes and grassland steppes on the east coast. Traps were set at locations with high-density nutria populations (i.e., those areas that showed signs of movement, territorial marking, or feeding activities). Although the small sample size limits the interpretation of these findings, RIs were determined by a robust method using the central 95th percentile. In nutria, the RI range varied greatly for the leukocyte differentials, with mature neutrophils: 3,907-5,544/μl for females and 3,744-5,900/μl for males; band neutrophils: 0-10/μl for females and 3-18/μl for males; lymphocytes: 4,213-5,940/μl for both sexes combined; monocytes: 165-402/μl for both sexes combined; eosinophils: 13-91/μl for females and 108-165/μl for males; and basophils: 0-87/μl for both sexes combined. Platelet concentration was 543-727 × 109/L for both sexes combined. There was also a wide RI range for biochemistry values for some enzymes, such as alkaline phosphatase: 200-399 IU/L for both sexes combined; cholinesterase: 762-1,407 IU/L for females and 763-1,284 IU/L for males; creatine kinase: 182-552 IU/L for females and 162-451 IU/L for males; amylase: 853-1,865 IU/L for females and 779-1,293 IU/L for males; and glucose concentration 120.2-180.6 mg/dl for both sexes combined. Conversely, there was not a wide pooled RI range for calcium: 7.0-11.2 mg/dl; phosphorous: 6.1-9.3 mg/dl; sodium: 133.0-159.0 mEq/L; potassium: 3.0-8.2 mEq/L; chloride: 101.4-143.0 mEq/L; and urea: 11.3-36.8 mg/dl.The red blood cell indices had a narrow range, with mean corpuscular volume: 84.0 -102.5 fl and mean corpuscular hemoglobin concentration: 18.2-28.8 g/dl, and which was most likely due to strict physiologic controls. The results from this study were similar to those previously reported for farmed nutria. © 2012 American Association of Zoo Veterinarians.