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Biomedical subjects

J Delgado

Publications and source records attributed to J Delgado.

At least 145 records · Page 8Linked to original sources
PubMedDate not supplied

Solid substrate fermentation of Monascus purpureus: growth, carbon balance, and consistency analysis.

Solid substrate fermentation (SSF) of Monascus purpureus on rice is a promising new technology for obtaining natural pigments. However, before attempts can be made at maximizing pigment yield, all significant macroscopic compounds should be assayed. Here, Monascus purpureus has been grown on rice in batch mode, and the evolution of the main components, biomass, residual rice, O(2), CO(2), ethanol, acetic acid, and pigments, have been followed. This set of data, never previously studied for Monascus SSF, allowed both the performance of a macroscopic elemental balance, which accounted for 83-94% of the initial substrate carbon, and a check of data consistency. Standard consistency analysis showed a significant underestimation of the nitrogen fraction of biomass, but it was unable to discriminate the errors in the carbon balance as a result of the simultaneous presence of two gross errors in the system. A simple stoichiometric model in tandem with consistency analysis explained unaccounted carbon as an underestimation of CO(2) and ethanol. Using the simplified method to estimate ethanol, the macroscopic balance accounted for 87-99% of the initial carbon.

Acetic Acid↗
PubMedDate not supplied

Inverse flux analysis for reduction of acetate excretion in Escherichia coli.

The determination of intracellular fluxes from the measurement of extracellular rates, a technique known as flux analysis, has been used successfully on several systems important to biotechnology. However, calculation of intracellular fluxes does not directly suggest ways to improve the performance of the cell. Here, we introduce a variation of this analysis, termed inverse flux analysis, which allows the prediction of the flux distribution as a function of manipulable internal fluxes. This approach is applied to analyze the acetate excretion problem commonly observed in aerobic Escherichia coli cultures. The effect of manipulating each flux is quantified by a flux distribution sensitivity coefficient, which is dependent on the stoichiometry. For the acetate excretion problem, our results suggest that the anaplerotic pathways, including the reactions catalyzed by phosphoenolpyruvate carboxylase and the glyoxylate bypass are the best choices for manipulating acetate excretion in E. coli. Increasing the anaplerotic flux will decrease acetate production while increasing the growth yield.

Acetates↗
PubMedDate not supplied

Reemergence of dengue in Cuba: a 1997 epidemic in Santiago de Cuba.

After 15 years of absence, dengue reemerged in the municipality of Santiago de Cuba because of increasing migration to the area by people from disease-endemic regions, a high level of vector infestation, and the breakdown of eradication measures. The 1997 epidemic was detected early through an active surveillance system. Of 2,946 laboratory-confirmed cases, 205 were dengue hemorrhagic fever, and 12 were fatal. No deaths were reported in persons under 16 years of age. Now the epidemic is fully controlled.

Aedes↗
PubMedDate not supplied

[From rings to segregation. Mexico City, 1950-1987].

The author discusses different methods of urban analysis, using the example of Mexico City, Mexico. "In this work two outlines are used: a concentric one that reflects the city's expansion and a segregated one that sees the 'different cities' within. We analyze the commercial occupation of central areas and the growth due to the expansion of the periphery from 1950 to 1986. In both processes, the massive expulsion of the inhabitants appears, firstly as an effect and secondly as a cause. This fact serves as an argument to explore certain proposals in a prospective dimension. In the technical [spatial] analysis we generally avoid the design of the city itself. Here we approach some design ideas without forgetting their social dimension." (SUMMARY IN ENG)

Americas↗
PubMedDate not supplied

The study cellular subpopulations in peripheral blood from a normal reference group population (blood donors).

The spectacular development of monoclonal antibodies against cellular antigens an technology such as flow cytometry allow the investigation of cellular subpopulations that until now have been unknown. At the same time, the functional study of these subpopulations becomes of maximal interest, as this information could have future applications for pathological processes. Due ti this basic need for information, we have studied diverse lymphocytic subpopulations in a normal population that serves as a reference group, using the following antigens: CD3, CD4, CD8, CD20, CD45RA, CD25, LAM1, CD29, CD11b and CD23. Some of these subpopulations had not been previously studied in a normal reference group.

Antibodies, Monoclonal↗
PubMedDate not supplied

Modified immunoassays for polyether toxins: implications of biological matrixes, metabolic states, and epitope recognition.

Polyether marine toxins are responsible for the seafood intoxication phenomena known as neurotoxic shellfish poisoning (due to brevetoxins), ciguatera (due to ciguatoxin), and diarrheic shellfish poisoning (due to okadaic acid). Using traditional techniques of hapten (pure toxin) conjugation to protein to create complete antigen, animal immunization and antibody isolation, and specific antibody subpopulation purification, discriminating antibodies have been isolated that detect brevetoxins and ciguatoxin, but not okadaic acid, in a dose-dependent fashion. Using microorganic chemistry and purified toxins, a unique set of tools has been created for the study of polyether ladder toxin accumulation; depuration; and specific site localization in tissues, food sources, and clinical samples. Developed test protocols can detect toxin in dinoflagellate cells, in extracts from food sources, in seawater and culture media, and in human serum samples. Enzyme-linked immunosorbent assay protocols developed for eventual collaborative testing have been successful in limited applications within the laboratory (correlation coefficient of 0.92 excluding 2 outliers), and alternative formats are being developed to optimize the basic test for use in research laboratories, regulatory laboratories, and field inspections.

Antibodies↗
PubMedDate not supplied

Variations of the cellular antigens CD4 and CD8 in pollinic patients during the spring.

In order to study the possible variations of CD4 and CD8 antigens in pollinic patients, we have studied 25 individuals (11 rhinoconjunctivitis and 14 rhinoconjunctivitis-asthma) before (T0), in the middle (T1) and after the spring (T2). The number of receptors per cell of CD4 start from values in T0, decrease in T1 and increase at the end of the spring (p < 0.00001), which could represent a mechanism to limit the clonal response to an antigen. An increase in the CD4/CD8 bright ratio could be indicate a higher helper mechanism in T1 with respect to T0 and T2 (p < 0.01). The opposite meaning is to given to the increase of CD8bright receptors in the asthmatic patients, and not only in those who suffer only from a rhinopathy (the only difference between the two groups of patients) during T2 over the T1 (p < 0.00001). The greater number of lymphocytes CD8 dim + during T1 with respect to T2 (p < 0.009) and the increase in the number of receptors of such cells during T1 with respect to T2 (p < 0.00001) suggests a possible intervention of these cells in the regulation of the response of the B and T lymphocytes. Of the two soluble factors CD4 (sCD4) and CD8 (sCD8), only the sCD4 increases during T1 (p < 0.0001) in an inverse manner as occurs with CD4 cell receptors, while the sCD8 remains unchanged during the three periods.(ABSTRACT TRUNCATED AT 250 WORDS)

Asthma↗
PubMedDate not supplied

Plasma kallikrein amidolytic activity in patients with urticaria.

We have studied the plasma kallikrein amidolytic activity in healthy control subjects (inactive), patients with chronic urticaria (active) and patients with acute urticaria (active) from their admission to the emergency room (active) to the time after which their clinical symptomatology had disappeared (inactive). We found statistically significant differences (p < 0.01) in the active groups of urticaria patients. This leads us to believe that kallikrein participates in the development of symptomatology in these patients.

Female↗
PubMedDate not supplied

Food hypersensitivity among adult patients: epidemiological and clinical aspects.

Food hypersensitivity (FH) is lesser frequent among adult patients than in childhood. Foods implicated in hypersensitivity reactions vary with sociocultural and diet habits from a geographic place to other. We studied 142 adult patients sensitized to foods, among 7698 patients visited at our Outpatient Clinic. Hundred and twenty patients referred clinical symptoms after consumption of one or more foods consistently. From the latest, 107 patients (89.2%) were atopics (92 of them sensitizes to dust mites) and 54 (45%) referred atopic familiar background. Most frequent recorded symptoms were: urticaria/angioedema 84 cases (70%), oral syndrome 65 (54%), asthma 48 (37%) and anaphylaxis 33 patients (27.5%). Shellfish sensitization occurred in 50 patients, fresh fruits in 33 and nuts in 29 cases. Shrimp (48 patients), squid (33), kiwi (14), papaya (14), avocado (13) and banana (12 cases) were the most frequent causes of FH. Significant statistical association between foods and inhalants was observed for fresh fruits and latex (p < 0.001), fresh fruits and pollens (p < 0.01), and shellfish and Blatta germanica (p < 0.001). Prevalence of FH among patients at our Area is around 1.6%. Tropical fruits, as other kind of fruits, seem to share common IgE-epitopes to pollens. High prevalence of shellfish and cockroach hypersensitivity could be more easily developed by previous domestic mites sensitization.

Adult↗
PubMedDate not supplied

Increased serum IgE in acute type A, B and delta hepatitis.

Serum IgE levels have been documented in patients of acute type B hepatitis. There are very few studies on serum IgE in acute type A hepatitis and, to our knowledge, there are no data on serum IgE in acute delta hepatitis patients. The purpose of this study was to measure total IgE levels in 38 patients with acute A, B and delta hepatitis and in 181 controls in order to determine the possible existence of changes in this parameter in the course of these infections. Our results showed a relevant increase in IgE levels in the three groups (hepatitis A, B and delta) with respect to the control group. Moreover, the hepatitis B group showed increased total serum IgE levels with respect to the hepatitis delta group.

Acute Disease↗