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J Paniagua

Publications and source records attributed to J Paniagua.

30 records · Page 2Linked to original sources
PubMed1990

[Seroepidemiology of amebiasis in the northern region of the Republic of Mexico].

The object of paper has been the study of amebic seroepidemiology in the northern region of Mexico, by means of an immunoenzymatic assay in solid phase (ELISA). The proteic antigen was obtained from axenic culture of E. histolytica's trophozoites of strain HM1:IMSS, by means of solubilization with phenoxy polyethoxyethanol (Triton X-100). Standardization of the method was obtained by analysis of 80 sera from patients with both a clinical and radiologic diagnosis of amebic hepatic abscess and 80 sera from healthy patients. The sensitivity reached 95% and the specificity was 90.7%. 15,457 sera from eight Mexican northern states were tested as part of the National Seroepidemiologic Survey. A semiautomatic BIOMEK 1,000 (Beckman Ins.) equipment was used. The positive ratio varied between 2.0% in Southern Baja California and 4.92% in Chihuahua, with an average ratio for the whole group of 3.34%. The first three places, in descending order, are Chihuahua (4.92%), Sinaloa (4.01%) and Northern Baja California (3.78%). The positive man: woman ratio was 0.87:1 and fluctuated between 0.38:1 in Coahuila and 1.76:1 in Nuevo Leon. In the whole sample the positive ratio of men was 3.00% and in women was 3.43%. The antibody profile related to age, is similar to diseases reported to be highly endemic; the percentage of positive sera rose progressively up to the age of 20 years (4.05%), at which a plateau occurred with a slight descending tendency up to 60 years of age (3.54%), after which a clear descent in the positive index is seen. No important variations were observed when comparing groups of ages and sexes. The antibody level seems to show an inverse relationship with the incidence rate of amebiasis.

Adolescent↗
PubMed1989

[Study of lipids (cholesterol, triglycerides and phospholipids), plasma lipoproteins (HDL-cholesterol) and apoproteins (apo A and apo B in patients with acute myocardial infarction].

Several lipid parameters were evaluated in 88 patients with acute myocardial infarction (AMI). A reduction in cholesterol and phospholipid level was observed, with minimal values between the days 10-20, followed by a subsequent increase. Triglycerides increased after 12-14 hours, with a maximal value after 20-30 days. Cholesterol bound to high-density lipoproteins (HDL-cholesterol) decreased after 24 hours, with a minimal value after 20-30 days. Apoprotein A decreased from the initial measurement until days 20-30. The initial lipid profile (indicating the risk of coronary artery disease) was constituted by high cholesterol (particularly in males below 60 years), high triglyceride and low HDL-cholesterol levels. The latter finding was more marked and characteristic in the overall group of evaluated patients. All values were compared with a control group of 24 healthy persons. Relevant data for prognosis included the following: males above 60 years had a greater reduction in cholesterol and apoprotein A during AMI; the males who died had lower apoprotein A levels than the survivors; females with higher haptoglobin levels also had higher apoprotein B levels. All these findings were statistically significant (p less than 0.01).

Aged↗
PubMed1988

Protection against Salmonella typhi infection in mice after immunization with outer membrane proteins isolated from Salmonella typhi 9,12,d, Vi.

The current studies were undertaken to assess the ability of the outer membrane proteins (OMPs) of Salmonella typhi to induce protection against challenge with the bacteria in mucin. OMPs were isolated as described by Schnaitman (J. Bacteriol. 108:553-556, 1971) and were found to be contaminated with approximately 4% lipopolysaccharide (LPS). Immunization with as little as 30 micrograms of OMPs conferred 100% protection to mice challenged with up to 1,000 50% lethal doses (LD50) of two strains of S. typhi (9,12,d, Vi and Ty2). In addition, 30% protection against challenge with up to 500 LD50 of Salmonella typhimurium was achieved. Immunization with LPS at doses equivalent to those found in the OMPs was considerably inferior to the OMPs in the induction of an immune status. Moreover, LPS was effective only when the challenge was performed with S. typhi 9,12,d, Vi (40% protection to 100 LD50). An antiserum raised in rabbits reacted mainly against the bands of the molecular weights corresponding to the so-called porins contained in the OMP preparation as shown by Western blotting (immunoblotting). This rabbit antiserum protected 100% of mice against challenge with 100 LD50 of either strain of S. typhi and 80% of mice against challenge with the same LD50 of S. typhimurium. These results indicate the usefulness of OMPs in the induction of active immunity against S. typhi in mice.

Animals↗
PubMedDate not supplied

Self-sustaining Mars colonies utilizing the North Polar Cap and the Martian atmosphere.

A revolutionary new concept for the early establishment of robust, self-sustaining Martian colonies is described. The colonies would be located on the North Polar Cap of Mars and utilize readily available water ice and the CO2 Martian atmosphere as raw materials to produce all of the propellants, fuel, air, water, plastics, food, and other supplies needed by the colony. The colonists would live in thermally insulated large, comfortable habitats under the ice surface, fully shielded from cosmic rays. The habitats and supplies would be produced by a compact, lightweight (~4 metric tons) nuclear powered robotic unit termed ALPH (Atomic Liberation of Propellant and Habitat), which would land 2 years before the colonists arrived. Using a compact, lightweight 5 MW (th) nuclear reactor/steam turbine (1 MW(e)) power source and small process units (e.g., H2O electrolyzer, H2 and O2 liquefiers, methanator, plastic polymerizer, food producer, etc.) ALPH would stockpile many hundreds of tons of supplies in melt cavities under the ice, plus insulated habitats, to be in place and ready for use when the colonists landed. With the stockpiled supplies, the colonists would construct and operate rovers and flyers to explore the surface of Mars. ALPH greatly reduces the amount of Earth supplied material needed and enables large permanent colonies on Mars. It also greatly reduces human and mission risks and vastly increases the capability not only for exploration of the surrounding Martian surface, but also the ice cap itself. The North Polar Cap is at the center of the vast ancient ocean that covered much of the Martian Northern Hemisphere. Small, nuclear heated robotic probes would travel deep (1 km or more) inside the ice cap, collecting data on its internal structure, the composition and properties of the ancient Martian atmosphere, and possible evidence of ancient life forms (microfossils, traces of DNA, etc.) that were deposited either by wind or as remnants of the ancient ocean. Details of the ALPH system, which is based on existing technology, are presented. ALPH units could be developed and demonstrated on Earth ice sheets within a few years. An Earth-Mars space transport architecture is described, in which Mars produced propellant and supplies for return journeys to Earth would be lifted with relatively low DeltaV to Mars orbit, and from there transported back to Earth orbit, enabling faster and lower cost trips from Earth to Mars. The exploration capability and quality of life in a mature Martian colony of 500 persons located on the North Polar Cap is outlined.

Carbon Dioxide↗
PubMedDate not supplied

Immunogenicity of a Salmonella typhi CVD 908 candidate vaccine strain expressing the major surface protein gp63 of Leishmania mexicana mexicana.

Attenuated Salmonella typhi are attractive for use as live vector vaccines to express protozoal antigens and deliver them to the human immune system. The gene encoding the mature form of Leishmania mexicana mexicana gp63 under control of tac promoter was integrated into the delta aroC locus of the chromosome of attenuated delta aroC, delta aroD S. typhi strain CVD 908. After oral immunization of BALB/c mice with two 1 x 10(9) colony forming unit doses given 21 days apart, CVD 908 omega (delta aroC::Ptac-gp63) elicited a broad T cell-mediated immune response against L. m. mexicana gp63 as demonstrated by: (1) lymphoproliferative response to fixed whole L. m. mexicana promastigotes; (2) activation of IL-2 (but not IL-4)-producing lymphocytes; (3) appearance of cytotoxic T cells against mouse mastocytoma cells expressing gp63. This T-cell mediated immune response was associated with significant protection in F1 (BALB/cXC57Bl/6) mice challenged in their footpads with a wild type strain of L. m. mexicana.

Administration, Oral↗
PubMedDate not supplied

[Conjugate vaccines against bacterial infections: typhoid fever].

Capsular polysaccharides have been studied as possible vaccines against infectious diseases. However, they are capable to induce only short-run protection because of their T-independent properties and they would not be protective against infection in high-risk populations. The alternative to face this problem is to develop methods to join covalently the polysaccharide and proteins to both increase the immunogenicity of and to confer the property of T-dependence to this antigen. In order to obtain a conjugate vaccine against typhoid fever, in our laboratory we have tried to synthesize a conjugate immunogen between the Vi antigen and porins from Salmonella typhi.

Adolescent↗
PubMedDate not supplied

[Factors of Salmonella typhi virulence in relation to the development of new vaccines].

Although many vaccines against typhoid fever have been developed, none have been adapted for their further application on developing countries. In order to get better vaccines, the virulence factors of both S. typhi and S. typhimurium have been studied. Thus, some protection assays have been made using surface antigens involved on virulence or using live attenuated vaccines of bacteria mutated on virulence genes. Here we present a brief review about virulence factors studied so far for the development of new vaccines.

Adolescent↗
PubMedDate not supplied

[Monoclonal antibodies against the lipopolysaccharide of Salmonella typhi 9,12,VI:d. Analysis of passive protection in a mouse model of typhoid fever].

The current work was undertaken in order to assess the role of the monoclonal antibodies (Mabs) to lipopolysaccharide (LPS) of Salmonella typhi in the induction of passive protection against the challenge with the bacteria in a mice model. BALB/c mice were immunized with the whole bacteria, mice with high anti-LPS antibody titers were killed, the spleens were removed and splenocytes were fused with the mouse plasmocytoma SP2/0. Two IgM monoclonal antibodies against porins were developed. Each one of these Mabs recognized the polysaccharide region of LPS. Passive immunization with supernatant fluid of mice with one of these monoclonal antibodies did not protect against challenged with 20 LD50 and 100 LD50 of Salmonella typhi. The results suggest that LPS is not valuable immunogen for the induction of a protective status against typhoid fever.

Animals↗
PubMedDate not supplied

[Elaboration of an immunosorbent for the purification of porins from Salmonella typhi 9, 12, Vi:d].

The current work was undertaken to purify porins of Salmonella typhi, which are outer membrane proteins (OMPs) that induce protection in mice against challenge with the bacteria in mucin. OMPs, isolated with a non-ionic detergent, had a 4% contamination with LPS (endotoxin) and molecular sizes ranging from 17 to 70 KDa. Porins (Mw 38-41 KDa) were isolated from OMPs preparative SDS-PAGE. Anti-porins antisera were raised in rabbits and specific IgG was purified, which was coupled to Sepharose-CNBr. This immunosorbent was used to purify LPS-free porins.

Antibodies, Bacterial↗