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C Manzano

Publications and source records attributed to C Manzano.

At least 19 recordsLinked to original sources
PubMed2006

Interplay between thermodynamics and kinetics in the capping of InAs/GaAs(001) quantum dots.

A microscopic picture for the GaAs overgrowth of self-organized quantum dots is developed. Scanning tunneling microscopy measurements reveal two capping regimes: the first being characterized by a dot shrinking and a backward pyramid-to-dome shape transition. This regime is governed by fast dynamics resulting in island morphologies close to thermodynamic equilibrium. The second regime is marked by a true overgrowth and is controlled by kinetically limited surface diffusion processes. A simple model is developed to describe the observed structural changes which are rationalized in terms of energetic minimization driven by lattice mismatch and alloying.

Journal Article↗
PubMed2006

Determinants of early outcome in spontaneous lobar cerebral hemorrhage.

OBJECTIVE: To identify determinants of early outcome in spontaneous lobar hemorrhage. MATERIALS AND METHODS: From 2500 acute stroke patients included in a prospective hospital-based stroke registry over a 12-year period, 97 cases of lobar hematoma were selected. Determinants of in-hospital mortality were studied in multiple regression models. RESULTS: Lobar hematomas accounted for 3.9% of all acute stroke patients and 35.9% of intracerebral hemorrhages. The presence of chronic obstructive pulmonary disease (COPD) was a significant predictive variable in the model based on demographic variables and vascular risk factors [odds ratio (OR): 17.18; 95% CI: 1.77-166.22] and in the model based on these variables plus clinical data (OR: 15.12; 95% CI: 1.27-179.59). Other predictive variables included altered consciousness, previous cerebral infarct and chronic liver disease. CONCLUSIONS: COPD appeared as the most important predictor of death during hospitalization after lobar cerebral hemorrhage, a finding not generally acknowledged earlier.

Aged↗
PubMed2005

Significance of one human leukocyte antigen mismatch on outcome of nonmyeloablative allogeneic stem cell transplantation from related donors using the Mexican schedule.

Using the Mexican approach to conduct nonablative stem cell transplantation (NST), we have prospectively performed 58 allografts in individuals with various malignant and nonmalignant hematological diseases using sibling donors, either HLA identical (6/6) or compatible, with one mismatch (5/6). When comparing allografts obtained from HLA identical (n=40) or compatible (n=18) siblings, respectively, the overall median survival was found to be 33 vs 8 months (P<0.01), the 52-month survival was 47 vs 38% (P>0.2), the prevalence of acute graft-versus-host disease (GVHD) 57 vs 38%, that of chronic GVHD 25 vs 11% and the relapse rate 45 vs 55%. The two patients who failed to engraft were both 5/6 matches. Probably stemming from the low number of patients, and despite a trend toward worse results in patients allografted from HLA compatible (5/6) siblings, most differences in outcome were not significant. It seems that NST can be offered to individuals with either an HLA identical or a compatible sibling donor.

Blood Donors↗
PubMed2005

Bloodless (transfusion-free) hematopoietic stem cell transplants: the Mexican experience.

We have analyzed the transfusion requirements of a group of 132 peripheral blood stem cell transplants from a single institution (73 allografts and 59 autografts) over a 10-year period. The allografts were conducted using the 'Mexican' nonmyeloablative conditioning regimen, while the autografts were given single-day high-dose melphalan. For the allografts, the median number of transfused packed red blood (PRBC) cell units was 1 (range 0-22), while the median number of platelet transfusion (PLT) sessions was 1 (range 0-9); 45% of allografted individuals did not require PRBC transfusions and 35% did not require PLT. For autografts, the median number of PRBC units was 2 (range 0-21), while the median number of PLT was 2 (range 0-21); 33% of autografted individuals did not require PRBC and 25% did not require PLT. We conclude that, by using certain preparative regimens, both allo and auto hematopoietic stem cell grafts can be conducted without the transfusion of blood products.

Adolescent↗
PubMed2005

The early referral for reduced-intensity stem cell transplantation in patients with Ph1 (+) chronic myelogenous leukemia in chronic phase in the imatinib era: results of the Latin American Cooperative Oncohematology Group (LACOHG) prospective, multicenter study.

Using a reduced-intensity stem cell transplantation (RIST) schedule, 24 patients with Philadelphia (Ph1) (+) chronic myelogenous leukemia (CML) in first chronic phase (CP) were prospectively allografted in four Latin American countries: México, Brazil, Colombia and Venezuela, using HLA-identical siblings as donors. The median age of the patients was 41 years (range 10-71 years); there were eight females. Patients received a median of 4.4 x 10(6)/kg CD34 cells. The median time to achieve above 0.5 x 10(9)/l granulocytes was 12 days, range 0-41 days, and the median time to achieve above 20 x 10(9)/l platelets was also 12 days, range 0-45 days. In all, 22 patients are alive 81-830 (median 497) days after RIST. The 830-day probability of survival is 92%, and the median survival has not been reached, being beyond 830 days. A total of 11 patients (46%) developed acute graft-versus-host disease (GVHD), and seven of 23 (30%) developed chronic GVHD. Two patients died 43 and 210 days after RIST, one as a result of sepsis and the other of chronic GVHD. The 100-day mortality was 4.4%, and transplant-related mortality was 8%. RIST for patients with CML in CP appears to be an adequate therapeutic option.

Adolescent↗
PubMed2004

Atomic-scale pathway of the pyramid-to-dome transition during ge growth on Si(001).

By high resolution scanning tunneling microscopy, we investigate the morphological transition from pyramid to dome islands during the growth of Ge on Si(001). We show that pyramids grow from top to bottom and that, from a critical size on, incomplete facets are formed. We demonstrate that the bunching of the steps delimiting these facets evolves into the steeper dome facets. Based on first principles and Tersoff-potential calculations, we develop a microscopic model for the onset of the morphological transition, able to reproduce closely the experimentally observed behavior.

Journal Article↗
PubMed2004

Hierarchical self-assembly of GaAs/AlGaAs quantum dots.

A novel structure containing self-assembled, unstrained GaAs quantum dots is obtained by combining solid-source molecular beam epitaxy and atomic-layer precise in situ etching. Photo-luminescence (PL) spectroscopy reveals light emission with very narrow inhomogeneous broadening and clearly resolved excited states at high excitation intensity. The dot morphology is determined by scanning probe microscopy and, combined with single band and eight-band k.p theory calculations, is used to interpret PL and single-dot spectra with no adjustable structural parameter.

Journal Article↗
PubMed2003

DNA polymorphisms detect ancient barriers to gene flow in Basques.

This work features the first district-by-district analysis of all provinces in the Iberian Peninsula with an autochthonous Basque population, and indicates the existence of genetic heterogeneity. The populations cluster in three groups arising from processes of genetic drift which probably occurred in pre-Mesolithic times, and were probably those which repopulated the southern areas of the Basque Country after the Last Glacial Maximum. It seems that from that period onwards, the population settled in three major groups (West Basques, Central Basques, and East Basques), along geographical axes which appear substantial in the maintaining of each population unit. This genetic structure is probably reflected in other aspects such as the existence of ancient tribes and the dialects of the Basque language, the boundaries of which may be related at origin and which are quite similar to those detected in this work. Our results indicate that the populations of the Basque Country are genetically close to other neighboring populations, such as that of Aragon, which may indicate an outgoing gene flow from the Basque area down the River Ebro towards the Mediterranean seaboard. While our short tandem repeat data suggest that population structure within the Basques dates back to the Mesolithic, our findings are also consistent with the hypothesis that patterns of modern European genetic diversity have been shaped mainly during the Neolithic.

DNA↗
PubMed2002

Structuring the genetic heterogeneity of the Basque population: a view from classical polymorphisms.

In this study we analyze 18 classical polymorphisms (ABO, Rh, MNSs, Lewis, P, Duffy, Kell, ADA, ESD, PGM1, PGD, AK1, ACP1, GLO1, HP, GC, TF, and PI) in over 2000 autochthonous individuals from 14 natural districts in three provinces of the Basque Country (Alava, Guipuzcoa, and Biscay). Heterogeneity analysis via the chi2 test and a calculation of F(ST) indicate that there is significant genetic heterogeneity between the Basque districts. The R matrix informs us that this heterogeneity is not significantly concentrated in a single district or in the districts of a single province, but is rather distributed among several districts belonging to the three provinces analyzed. We undertake to assess the influence of various historical, geographical, and cultural factors on the genetic structure of the Basque population. Analysis suggests that allele distribution is geographically patterned in the Basque Country. The gradient distributions observed in the case of some alleles (ABO*O, RH*cDE, RH*cde, MNS*MS, and ACP1*C) on the basis of Moran's autocorrelation coefficient I, along with the influence of the two main travel routes through the Basque Country (western route through Bilbao and eastern route through Vitoria), suggest that the gene flow tends toward the coast. As regards other factors considered (administrative division, repopulation processes, linguistic heterogeneity, and north vs. south cultural heterogeneity), we detected only a certain influence exerted by an old tribal differentiation (2000 B.P.), which would diminish with the passage of time.

Alleles↗
PubMed1999

Analysis of 6 short tandem repeat loci in Navarre (northern Spain).

A genetic study was performed on a sample of 146 autochthonous individuals from the province of Navarre (northern Spain) to test for 6 STR systems: CSF1PO, TPOX, TH01, F13A1, FES/FPS, and VWA31/A. The Navarre population has a series of allele frequencies that are at the extreme end of the European range of variation and that are in most cases similar to those found in the Basque population of the provinces of Alava, Biscay, and Guipuzcoa. This similarity is corroborated by correspondence analysis, in which the population of Navarre is at one end of the first axis with the Basque sample close to it and the remaining European populations far removed. In tree-type representations the Navarre population is grouped with the Basque series at 1 end. Even so, the comparison of allele frequency distributions by the chi-square heterogeneity test indicates that these 2 groups are statistically different. Our results together with the cultural relationship that exists between all the Basque-speaking provinces and the genetic heterogeneity described in earlier studies between the Basque provinces of Alava, Biscay, and Guipuzcoa (Aguirre et al. 1989; Manzano, Orue et al. 1996; Manzano, Aguirre et al. 1996) lead us to believe that the Navarre population lies within the heterogeneous Basque genetic map.

Chi-Square Distribution↗
PubMed1996

The "Basqueness" of the Basques of Alava: a reappraisal from a multidisciplinary perspective.

The genetic and linguistic peculiarity of the Basque population is well known. Analysis of the studies published to date on the Basque population reveals that these studies refer basically to the provinces of Vizcaya and Labourd, both in the Northern part of the Basque Country. Multidisciplinary information indicates that the landscape differences of the Basque Country could have conditioned differential population biodynamics in the Atlantic and Mediterranean parts of the Basque area. In order to evaluate this possibility, this study focuses on the genetic constitution of the Basque population of Alava (in the South of the Basque Country) through the analysis of several red-cell systems. The data obtained in this genetic study and those from archaeology, linguistics, ethnography, and skeletal biology suggest that within the "Basque population" there may be at least two distinct groups: an "Atlantic" group and a "Mediterranean" one, divided mainly by the watershed. This geographical feature could have led to a greater genetic isolation of the Northern slopes, with the South more open to population contact. This is reflected nowadays in the different cline distribution detected for most systems in the Alava Basques in comparison with other Basque and Iberian Peninsula series studied to date.

ABO Blood-Group System↗
PubMed1996

HLA-DQA1 in autochthonous Basques: description of a genocline for the DQA1*0201 allele in Europe.

A total of 250 autochthonous Basque individuals were tested in the HLA-DQA1 system, and the allele frequency distribution found was significantly different from that of any other European population. The differences centre mainly on the alleles DQA1*0201 and DQA1*0501: for the former the Basques have the highest frequency described anywhere in the world (f = 0.210) and for the latter they have the lowest frequency in Europe (f = 0.204). For the allele DQA1*0201 a genocline is also described in Europe with the Basques and Finno-Ugric populations basically at the extremes. The genocline reflects the isolation of the Basque population since prehistoric times, and supports existing linguistic, archaeological and genetic data.

Adult↗
PubMed1993

Genetic polymorphism of inter-alpha-trypsin inhibitor (ITI) in the Basque Country (northern Spain).

The genetic polymorphism of inter-alpha-trypsin inhibitor (ITI) was analyzed in 2 samples of 554 residents and 303 autochthonous healthy unrelated individuals from the Basque Country (northern Spain), by isoelectric focusing on miniaturized polyacrylamide gels followed by immunoblotting. The allele frequencies were ITI*1 = 0.586, ITI*2 = 0.402 and ITI*3 = 0.012 in residents and ITI*1 = 0.548, ITI*2 = 0.449 and ITI*3 = 0.003 in the autochthonous population. These allele frequencies were compared with those reported in other European populations.

Alpha-Globulins↗
PubMed1980

Peculiar face, pectus carinatum and joint laxity in brother and sister.

This report describes a probably new syndrome seen in a brother and sister and characterized by joint laxity, pectus carinatum and a peculiar face with mild frontal bossing, low nasal bridge, lateral displacement of the inner malar hypoplasia, parrot-like nose, chubby cheeks, striking philtrum and arched upper lips.

Abnormalities, Multiple↗
PubMed1979

Trichuriasis. Roentgenographic features and differential diagnosis with lymphoid hyperplasia.

Twenty patients with massive trichuriasis were studied with double contrast barium enema. The following changes were observed: 1) Impregnation defects of the colonic wall probably due to abundant mucous secretions. 2) Granular features. 3) Pear-shaped caecum. 4) Radiolucid ringlike images with some contrast material in its center, similar to those seen in lymphoid hyperplasia. On closer observation it was seen that the radiolucid ring was not complete and was continued by a prolongation which corresponds to the whipworm. This feature is central to the differential diagnosis.

Cecum↗