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E Cuevas

Publications and source records attributed to E Cuevas.

At least 19 recordsLinked to original sources
PubMed2006

The genetic structure of the gynodioecious Kallstroemia grandiflora (Zygophyllaceae): the role of male sterility and colonization history.

In gynodioecious populations, the frequency of females is expected to have a strong influence on the contemporary genetic structure of populations. Historical patterns of range contraction and expansion are also known to influence the genetic diversity of plant populations. We explore the influence of male sterility and colonization history on the genetic diversity in populations of Kallstroemia grandiflora along the Pacific of México. Both the overall population Fis and Fis values of hermaphrodites showed a negative association with female frequency. Genetic diversity declined with latitude. Our results provide evidence that females have a significant effect on the genetic structure as predicted by theoretical models and provide support for the hypothesis that historical processes have modified the genetic structure of K. grandiflora.

Desert Climate↗
PubMed2006

Participation of estradiol and progesterone in the retrograde labeling of pubococcygeus motoneurons of the female rat.

Retrograde labeling with horseradish peroxidase conjugated to wheat germ agglutinin showed that the pubococcygeus muscles of the female rat are innervated by a population of motoneurons located in a column approximately 2 mm in length in the central region of lamina IX of the sixth lumbar-first sacral spinal cord segments. These neurons have a dendritic distribution that projects to the lateral, medial and ventral regions of the gray matter. Values for soma size, primary dendrite length and arborization area obtained from intact animals that were in diestrous-2, were significantly reduced following ovariectomy. After hormone priming of the ovariectomized animals with estradiol benzoate and progesterone, an additional injection of estradiol benzoate alone or followed by progesterone increased the labeled length of the primary dendrites distributed to the lateral, but not to the medial or ventral regions of the gray matter in the spinal cord. However, dendritic labeling was not significantly increased when only progesterone was additionally injected. It therefore seems that pubococcygeus muscle motoneurons of the female rat are sensitive to the effects of gonadal hormones.

Animals↗
PubMed2005

Predictors of glycaemic control in indigent patients presenting with diabetic ketoacidosis.

AIM: To derive predictors of good glycaemic control in patients presenting with diabetic ketoacidosis (DKA) followed prospectively in a specialized clinic. METHODS: One hundred and sixty-one adult patients were admitted during a 31-month period and followed for at least 12 months. After 1 year, the patients were classified into three groups: good control (GC) (HbA1c < or = 7%), intermediate control (IC) (HbA1c 7-9%) and poor control (PC) (HbA1c > 9%). Characteristics of patients in the three groups were compared both at baseline and during follow-up. RESULTS: At 12 months, 36% of the patients were classified as GC, 27% as IC and 37% as PC. GC patients had higher fasting serum C-peptide levels 0.7 +/- 0.54 compared to 0.38 +/- 0.29 and 0.16 +/- 0.21 nmol/l, respectively, for the IC and PC patients (p < 0.0001). A higher proportion GC patient had a C-peptide level greater than 0.33 nmol/l than that for IC and PC patients (86, 61 and 19%, respectively; p < 0.0001). Exogenous insulin was safely discontinued in 50, 30 and 3% of patients, respectively, in the GC, IC and PC groups (p < 0.0001). Compliance with life-style interventions was higher in the GC than that in IC and PC patients (87, 41 and 5%, respectively; p < 0.0001). In the logistic regression analysis, predictors of good glycaemic control were having baseline fasting serum C-peptide value > or =0.33 mmol/l, OR: 3.01 (95% CI 1.07-8.55, p = 0.03) and compliance with life-style interventions OR 12.66 (95% CI 3.73-51.57, p = 0.0001). CONCLUSION: Among adult patients with DKA, significant predictors of good glycaemic control are preserved beta-cell function and compliance with life-style modifications.

Adult↗
PubMed2004

Correlation analysis between tumor-associated antigen sialyl-Tn expression and ST6GalNAc I activity in human colon adenocarcinoma.

OBJECTIVES: Sialyl-Tn (sTn) is a mucin carbohydrate-associated antigen that is strongly expressed in a large number of colorectal carcinomas. In this study, we combined immunohistochemical and enzymatic techniques in order to find the correlation between sTn tissue expression and the sialyltransferase activity (ST6GalNAc I) responsible for its synthesis in colorectal cancer (CRC) patients. METHODS: We compared sTn expression in healthy (n = 46), tumorous (n = 60) and transitional tissue (n = 46) from CRC patients, and correlated sTn altered expression with clinicopathologic variables of the patient. Furthermore, we determined ST6GalNAc I tissue activity employing asialo-ovine submaxillary mucin (asialo-OSM) as glycoprotein acceptor (n = 27). RESULTS: The rates of sTn positive expression obtained for healthy, tumorous and transitional tissues were 15, 67 and 63%, respectively. These rates led to statistically significant differences between healthy and tumorous or transitional tissue (p = 0.001); sTn expression was related to the first stages of the tumor invasion in transitional tissue. As regards ST6GalNAc I activity, we found an enhancement in transitional tissue. Statistical correlation analysis did not reveal association between sTn expression and ST6GalNAc I activity. CONCLUSIONS: Our findings indicated that sTn antigen tissue expression and ST6GalNAc I activity levels were not correlated in CRC, in spite of the overexpression of the antigen in tumorous and transitional tissue.

Adenocarcinoma↗
PubMed2001

Fluctuations of the correlation dimension at metal-insulator transitions.

We investigate numerically the inverse participation ratio, P(2), of the 3D Anderson model and of the power-law random banded matrix (PRBM) model at criticality. We found that the variance of lnP(2) scales with system size L as sigma(2)(L) = sigma(2)(infinity)-AL(-D(2)/2d), with D(2) being the correlation dimension and d the system dimension. Therefore the concept of a correlation dimension is well defined in the two models considered. The 3D Anderson transition and the PRBM transition for b = 0.3 (see the text for the definition of b) are fairly similar with respect to all critical magnitudes studied.

Journal Article↗
PubMed2001

Anomalously large critical regions in power-law random matrix ensembles.

We investigate numerically the power-law random matrix ensembles. Wave functions are fractal up to a characteristic length whose logarithm diverges asymmetrically with different exponents, 1 in the localized phase and 0.5 in the extended phase. The characteristic length is so anomalously large that for macroscopic samples there exists a finite critical region, in which this length is larger than the system size. The Green's functions decrease with distance as a power law with an exponent related to the correlation dimension.

Journal Article↗
PubMed2001

Deposition of semi-volatile organochlorine compounds in the free troposphere of the eastern North Atlantic Ocean.

Deposition samples were taken at a height of 2367 m above sea level (m.a.s.l.) on the Island of Tenerife from May 1999 until July 2000 and analysed for 19 polychlorinated biphenyl (PCB) congeners, hexachlorobenzene (HCB), hexachlorocyclohexanes (HCH) and DDTs. This site is located above the inversion layer, so samples represent background concentrations of the free troposphere. The average deposition fluxes of HCB, total HCH, DDTs and PCBs were 86, 400, 110 and 780 ng m(-2) yr(-1), respectively, being lower than those reported at sea level in continental or marine areas. All compounds are generally found in higher abundance in the wet precipitation samples. However, these samples only represent a fraction, e.g. 33%, of the total deposition load. Annual mass balance calculations show that wet precipitation is essentially responsible for the deposition of the low molecular weight OC whereas dry deposition accounts for more than 50% of the higher molecular weight PCBs.

Air Movements↗
PubMed1999

Correlation decay in quantum chaotic billiards with bulk or surface disorder.

We study the decay properties of correlation functions in quantum billiards with surface or bulk disorder. The quantum system is modeled by means of a tight-binding Hamiltonian with diagonal disorder, solved on LxL clusters of the square lattice. The correlation function is calculated by launching the system at t=0 into a wave function of the regular (clean) system and following its time evolution. The results show that the correlation function decays exponentially with a characteristic correlation time (inverse of the Lyapunov exponent lambda). For small enough disorder the Lyapunov exponent is approximately given by the imaginary part of the self-energy induced by disorder. On the other hand, if the scaling of the Lyapunov exponent with L is investigated by keeping constant l/L, where l is the mean free path, the results show that lambda is proportional to 1/L.

Journal Article↗
PubMed1996

Serological reactivity to a synthetic analog of phenolic glycolipid I and early detection of leprosy in an area of low endemicity.

A total of 23,863 individuals living in an area of low endemicity for leprosy were tested by enzyme-linked immunosorbent assay with a semisynthetic analogue of the phenolic glycolipid I antigen of Mycobacterium leprae. The proportion found positive was 3.86% which was significantly higher than that in a sample of a population known to be free of leprosy. Clinical examinations as well as Mitsuda and skin smear tests were organized for those defined as seropositive. The proportion of individuals with lepromin reactions of less than 3 mm increased 18.9% per serological interval as antibodies rose though it was not statistically significant. As a result of the clinical and bacteriological examinations, 2 cases with clinical signs and heavy bacillary load were found, whereas acid-fast bacilli were demonstrated in 2 other individuals without clinical manifestations of leprosy. The usefulness of the system for control purposes is discussed.

Adolescent↗
PubMed1993

Primary pleomorphic T-cell lymphoma of the spleen.

We report a case of primary splenic T-cell lymphoma that posed difficult problems in differential diagnosis with erythrophagocytic T-gamma lymphoma and inflammatory pseudotumor of the spleen. The need for immunophenotypic and molecular studies for establishing the correct diagnosis and the importance of early detection and treatment, is emphasized in the light of the relatively good prognosis of splenic lymphoma, diagnosed in the early stages of disease.

Aged↗
PubMed1992

[The immunological characterization of 63 cases of Hodgkin's disease with a panel of 8 antibodies].

Sixty three cases of Hodgkin's disease are studied (two with lymphonodular predominance, 15 with diffuse lymphocyte predominance, 26 nodular sclerosis, 15 mixed cell and 5 lymphocyte depletion) with a panel of 8 monoclonal antibodies, material routinely used and included in paraffin: Ber H2 (CD30), Leu M1 (CD15), Common Leukocyte Antigen (CD45), L26 (CD20), MB2, UCHL1 (CD45 RO), MTI (CD43) and Epithelial Membrane Antigen. Ber H2 turned out to be the most usefull marker, positive in 100% of cases, independently of the histologic type. Positiveness with Leu M1 ranged from 100% (2/2 cases) of lymphonodular predominance, to 53.3% (8/15 cases) of diffuse lymphocyte predominance. The reactivity of the rest was variable, 1 though it is note worthy the positiveness of B markers (L26, MB2) in the two cases with lymphonodular predominance. In the other subtypes, reactivity with L26 was greater than that with MB2. T cell marker expression was minimal, except for the positiveness in 40% of cases (2/5) of the lymphocyte depletion type. In addition, the results of other series are revised and as a result the possible histogenesis of Hodgkin's disease is discussed.

Antibodies, Monoclonal↗