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Hernandez-Becerril D.U.,National Autonomous University of Mexico | Nelson N.R.,University of Puerto Rico-Ponce Campus | Baron-Campis S.A.,Instituto Nacional Of Pesca | Moreno-Gufierrez S.P.,National Autonomous University of Mexico
Cryptogamie, Algologie | Year: 2013

In this paper, we show morphological features of two marine planktonic diatoms that are phylogenetically related, as suggested by molecular studies: Bellerochea malleus and Helicotheca tamesis. In order to study Bellerochea malleus specimens of the species were isolated from samples collected from marginal coral reefs located in the southern portion of Puerto Rico and cultured in the laboratory. Specimens of the species Helicotheca tamesis were isolated from net phytoplankton samples collected from the tropical Mexican Pacific and also cultured in the laboratory. The two species were examined by means of light and scanning electron microscopy. The morphology of Bellerochea malleus agrees well with previous reports: cells arranged in relatively long chains, united by the horn-shaped apical elevations, elliptical valves (not triangular) with depressed valve face bearing an eccentric annulus, from which numerous costae radiate, formation of costate ocelli, and one eccentric or marginal protruded and tubular rimoportula per valve. Helicotheca tamesis also shows the typical morphological features of this species: cells are solitary or form long and distinctly twisted chains, with no apparent apertures between sibling valves, valves are linear to elliptical, weakly silicified and flat. Furthermore, we found one conspicuous and protruded rimoportula per valve, located eccentrically or marginally (not central as previously described), consisting of an elliptic tubular structure. The cingulum is composed of numerous half-bands and segmented copulae. This study compares the morphology of these two species, with a special emphasis on the structure of the rimoportulae. © 2013 Adac. Tous droits réservés.

Castro M.D.R.,University of Puerto Rico at San Juan | Suarez E.,Ponce School of Medicine & Health Sciences | Suarez E.,University of Puerto Rico-Ponce Campus | Kraiselburd E.,University of Puerto Rico at San Juan | And 4 more authors.
Experimental Gerontology | Year: 2012

While the mechanisms of cellular aging remain controversial, a leading hypothesis is that mitochondrial oxidative stress and mitochondrial dysfunction play a critical role in this process. Here, we provide data in aging rhesus macaques supporting the hypothesis that increased oxidative stress is a major characteristic of aging and may be responsible for the age-associated increase in mitochondrial dysfunction. We measured mitochondrial DNA (mtDNA) damage by quantitative PCR in liver and peripheral blood mononuclear cells of young, middle age, and old monkeys and show that older monkeys have increases in the number of mtDNA lesions. There was a direct correlation between the amount of mtDNA lesions and age, supporting the role of mtDNA damage in the process of aging. Liver from older monkeys showed significant increases in lipid peroxidation, protein carbonylations and reduced antioxidant enzyme activity. Similarly, peripheral blood mononuclear cells from the middle age group showed increased levels in carbonylated proteins, indicative of high levels of oxidative stress. Together, these results suggest that the aging process is associated with defective mitochondria, where increased production of reactive oxygen species results in extensive damage at the mtDNA and protein levels. This study provides valuable data based on the rhesus macaque model further validating age-related mitochondrial functional decline with increasing age and suggesting that mtDNA damage might be a good biomarker of aging. © 2011 Elsevier Inc.

University of Puerto Rico-Ponce Campus | Entity website

Laevangelizacin sedefine como la proclamacin delEvangelio delReino de Dios, de la Buena Nueva de laSalvacin que Cristo hizorealidad histrica y viviente en su personaa lo largo de suexistencia terrena. En estrecha y esencial dependencia de la evangelizacin est la Pastoral ...

University of Puerto Rico-Ponce Campus | Entity website

Alicea-Serrano A.M.,University of Puerto Rico-Ponce Campus | Contreras M.,Venezuelan Institute for Scientific Research | Magris M.,Amazonic Center for the Research and Control of Tropical Diseases | Hidalgo G.,Amazonic Center for the Research and Control of Tropical Diseases | And 2 more authors.
Archives of Microbiology | Year: 2013

Newborns acquire their first microbiota at birth. Maternal vaginal or skin bacteria colonize newborns delivered vaginally or by C-section, respectively (Dominguez-Bello et al. 2010 #884). We aimed to determine differences in the presence of four tetracycline (tet) resistance genes, in the microbes of ten newborns and in the mouth and vagina of their mothers, at the time of birth. DNA was amplified by PCR with primers specific for [tet(M), tet(O), tet(Q), and tet(W)]. Maternal vaginas harbored all four tet resistance genes, but most commonly tet(M) and tet(O) (63 and 38 %, respectively). Genes coding for tet resistance differed by birth mode, with 50 % of vaginally delivered babies had tet(M) and tet(O) and 16 and 13 % of infants born by C-section had tet(O) and tet(W), respectively. Newborns acquire antibiotic resistance genes at birth, and the resistance gene profile varies by mode of delivery. © 2013 Springer-Verlag Berlin Heidelberg.

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