Low Expression of IL-10 in Circulating Bregs and Inverted IL-10/TNF-α Ratio in Tears of Patients with Perennial Allergic Conjunctivitis: A Preliminary Study.

Allergic conjunctivitis (AC) is one of the most common ophthalmological disorders seen in clinical practice. Growing evidence from recent years suggests that a subset of IL-10-expressing B cells is involved in inflammatory allergic diseases. In this study, we aimed to evaluate the potential involvement of blood Bregs cells in perennial allergic conjunctivitis (PAC), and interleukins (IL)-1ß, IL-6, IL-8, IL-10, and IL-12, and tumor necrosis factor (TNF)-α, were measured in tear samples and compared with healthy controls (HC) using flow cytometry. Non-significant differences in CD19⁺IL-10⁺ cell frequency between PAC patients and healthy controls (HC) were observed. Nevertheless, when we analyzed the mean fluorescence intensity (MFI) of IL-10 on CD19⁺CD38Lo/Med/Hi-gated cells, we observed a significant decrease in MFI in all Bregs subsets in PAC patients. Additionally, tear cytokines showed 2.8 times lower levels of IL-10 than TNF-α in PAC patients when compared to HC. Our findings demonstrate an immunological dysregulation in patients with allergic conjunctivitis, characterized by the low expression of IL-10 in circulating CD19⁺CD38⁺ Bregs subsets and an inverted tear IL-10/TNF-α ratio, promoting a local pro-inflammatory microenvironment. These findings highlight the novel pathologic changes involved in ocular allergic diseases. Understanding systemic and local mechanisms will aid the design of immunomodulating therapeutics at different levels.

Intracellular IL-4, IL-5, and IFN-γ as the main characteristic of CD4+CD30+ T cells after allergen stimulation in patients with vernal keratoconjunctivitis.

BACKGROUND: Vernal keratoconjunctivitis (VKC) is a severe form of allergic conjunctivitis, in which inflammatory infiltrates of the conjunctiva are characterized by CD3+ and CD30+ cells. Until today, the functional involvement of CD30+ T cells in VKC was unclear. Our aim was to evaluate the functional characteristics of CD30+ T cells after allergen stimulation in peripheral blood mononuclear cells obtained from patients with VKC. METHODS: Seventeen consecutive patients at the Institute of Ophthalmology with active forms of VKC were included. RESULTS: After allergen stimulation, we observed the frequency of CD30+ T cells increased compared with non-stimulated cells (p<0.0001). The CD30+ T cells responded to the specific allergen-inducing expression of intracellular interleukin-4 (IL-4), IL-5, and interferon-gamma (IFN-γ) compared with the CD30- T cells (p<0.0001). Increased early secretion of soluble CD30 was observed in the supernatant of the cultured cells from patients with keratoconjunctivitis, compared with healthy controls (p=0.03). Blockage with IL-4 significantly diminished CD30 frequency in the allergen-stimulated cells. CONCLUSIONS: Our results suggest that after allergenic stimulation, CD4+CD30+ cells are the most important source of IL-4, IL-5, and IFN-γ. IL-4 acts as an activation loop that increases CD30 expression on T cells after specific stimulation. These findings suggest that CD4+CD30+ T cells are effector cells and play a significant role in the immune pathogenic response in patients with vernal keratoconjunctivitis.

Pilot scale production of the vaccine adjuvant Proteoliposome derived Cochleates (AFCo1) from Neisseria meningitidis serogroup B.

The use of new adjuvants in vaccine formulations is a subject of current research. Only few parenteral adjuvants have been licensed. We have developed a mucosal and parenteral adjuvant known as AFCo1 (Adjuvant Finlay Cochleate 1, derived from proteoliposomes of N. meningitidis B) using a dialysis procedure to produce them on lab scale. The immunogenicity of the AFCo1 produced by dialysis has been already evaluated, but it was necessary to demonstrate the feasibility of a larger-scale manufacturing process. Therefore, we used a crossflow diafiltration system (CFS) that allows easy scale up to obtain large batches in an aseptic environment. The aim of this work was to produce AFCo1 on pilot scale, while conserving the adjuvant properties. The proteoliposomes (raw material) were resuspended in a buffer containing sodium deoxycholate and were transformed into AFCo1 under the action of a calcium forming buffer. The detergent was removed from the protein solution by diafiltration to a constant volume. In this CFS, we used a hollow fiber cartridge from Amicon (polysulfona cartridge of 10 kDa porosity, 1mm channel diameter of fiber and 0.45 m² area of filtration), allowing production of a batch of up to 20 L. AFCo1 were successfully produced by tangential filtration to pilot scale. The batch passed preliminary stability tests. Nasal immunization of BALB/c mice, induced specific saliva IgA and serum IgG. The induction of Th1 responses were demonstrated by the induction of IgG2a, IFNγ and not IL-5. The adjuvant action over Neisseria (self) antigens and with co-administered (heterologous) antigens such as ovalbumin and a synthetic peptide from haemolytic Streptococcus B was also demonstrated.

La gD2 coadministrada con el AFCo1 por vía intranasal induce inmunidad protectora contra virus de herpes simple tipo 2 en ratones / gD2 coadministered with AFCo1 by intranasal route induces protective immunity against Virus Herpes Simplex type 2 in mice

La infección por virus herpes simple tipo 2 (VHS-2) continúa siendo un problema de salud mundial. Esta infección es transmitida sexualmente y es la principal causa de úlceras genitales. La prevención de esta enfermedad requiere de la utilización de vacunas mucosales, pues las vacunas parenterales no han sido exitosas. Por otra parte, no existen adyuvantes mucosales, por lo que el desarrollo de estos es esencial para la estrategia de estas vacunas. La administración intranasal (IN) de la glicoproteína D del VHS-2 (gD2), coadministrada con el cocleato (AFCo1+gD2) sería igualmente efectiva con la gD2 incluida (AFCo1-gD2). Se inocularon ratones hembras C57BL/6 por la vía IN con gD2, contenida dentro del cocleato, coadministrada con el cocleato o gD2 sola. Se determinaron los niveles de IgG anti gD2 en suero y lavado vaginal, así como las subclases de IgG anti gD2 por ELISA. Se determinó la respuesta linfoproliferativa en células de bazo, el perfil de citoquinas Th1/Th2, los signos de la enfermedad y la protección frente al reto viral. Se observaron altos títulos de IgG e IgG2c anti gD2 en el suero de los animales inoculados con la gD2 y el AFCo1 como adyuvante. No se observaron diferencias significativas (p>0,05) entre los grupos que recibieron AFCo1+gD2 y los que recibieron AFCo1-gD2. Se observó un perfil de citoquinas tipo Th1 y un 100 por ciento de sobrevida en los grupos que recibieron el AFCo1 como adyuvante de la gD2, mientras que en el grupo que recibió la gD2 sola no se observó protección. Estos resultados indican que la gD2 puede ser utilizada coadministrada con AFCo1 por vía IN como un potencial candidato vacunal contra VHS-2(AU)

Sexually transmitted infections by Herpes Simplex Virus type 2 (HSV-2) are the leading cause of genital ulcers and a major public health problem worldwide. This requires the use of mucosal vaccines, because parenteral vaccines have not been successful. Presently, there are not mucosal adjuvants, for this reason the development of adjuvants is essential for mucosal vaccine strategies. The intranasal (IN) immunizations using HSV-2 glycoprotein D (gD2), coadministered with cochleate (AFCo1+gD2), would be an efficient candidate for future vaccines against HSV2, similar to the gD2 incorporated into AFCo1(AFCo1-gD2). Female C57Bl/6 mice were inoculated with AFCo1-gD2, AFCo1+gD2 or gD2 alone by IN route. The anti gD2 IgG in sera and vaginal fluids and IgG subclasses were measured by ELISA. The lymphoproliferative response in spleen cells, the Th1/Th2 cytokine profile, the protection and the signs of disease against viral challenge were measured. High titers of IgG and IgG2c subclasses were observed in sera of mice that received the gD2 and AFCo1 as adjuvant. No significant differences (p>0.005) were observed in the animals that received AFCo1+gD2 or AFCo1-gD2. a preferential Th1 cytokine profile and 100 percent of survival after challenge were observed in both groups that received the gD2 and AFCo1, while no survival was observed in the group that only received the gD2. These results showed that the gD2 can be used coadministered with AFCo1 by IN route as a potential vaccine candidate against HSV-2(AU)

The golden era of vaccine adjuvants.

A 5-day workshop on adjuvant for vaccines was held in Trinidad, Cuba, on the 16-21 May 2010. Organized by the Latin American Association for Immunology and the Cuban Society for Immunology, the workshop attracted more than 60 scientists from different parts of the world. The meeting summarizes current knowledge regarding vaccine adjuvants, including delivery systems and parasitic vaccines. Main discussion topics were the discovery of new adjuvant formulations, action mechanisms for adjuvants, adjuvants for a different route of immunization, focused on mucosal vaccines, and nano- and micro-particles as a delivery system. This article highlights the most important issues presented.

AFCo1 as nasal adjuvant of capsular polysaccharide from Neisseria meningitidis serogroup C induces systemic and mucosal immune responses.

Increasing emphasis is being placed on the mucosal administration of vaccines in order to stimulate mucosal as well as systemic responses. Findings from our group suggest that proteoliposome-derived cochleate (AFCo1) acts as a potent mucosal adjuvant. As an alternative to chemical conjugation, the current study aimed to determine the benefit of using AFCo1 to improve the mucosal and systemic immune responses to capsular polysaccharide of Neisseria meningitidis serogroup C (PsC), a model of a thymus-independent (TI) antigen. Therefore, intranasal (i.n.) immunization of 3 doses 1 week apart with AFCo1 plus PsC in mice was conducted. Highly specific anti-PsC IgA responses and an anti-PsC IgG response were obtained. The subclass pattern induced against PsC was similar to that induced with the meningococcal vaccine. In summary, AFCo1 as nasal adjuvant was demonstrated to be capable of eliciting mucosal and systemic specific responses against a TI antigen.

Mucosal and systemic immune responses of mice to tetanus toxoid coadministered nasally with AFCo1.

Mucosal immune responses are an early and important line of defense against pathogens. The current understanding of the mucosal immune system allows us to consider the use of nasal immunization for induction of antigen-specific immune responses at the mucosal surface and the systemic compartment. Mucosal adjuvants are key for developing novel mucosal vaccines and represent 1 approach to improving mucosal and systemic immunity. However, few mucosal vaccine adjuvants are currently approved for human use. Neisseria meningitidis B proteoliposome-derived cochleate (AFCo1 - Adjuvant Finlay Cochleate 1) has been demonstrated to be a potent mucosal adjuvant. The present work demonstrates that intranasal immunization of 3 doses of tetanus toxoid (TT) coadministered with AFCo1 in mice promotes high systemic and mucosal responses. The anti-TT IgG serum titers and the mucosal anti-TT IgA in saliva and vaginal wash were significantly higher than TT alone. The analysis of antibody subclasses showed that intranasal administration of AFCo1 + TT induced not only IgG1 but also IgG2a anti-TT antibodies at levels comparable to those obtained with TT vaccine (vax-TET). These data support the fact that AFCo1 is a potent mucosal adjuvant in nasal immunization to a coadministered protein antigen.

Adjuvantes: un componente esencial de las vacunas de Neisseria

Adjuvants may be classified into delivery systems and immune potentiator or modulator molecules based on their mechanism of action. Neisseria vaccines containing traditional adjuvants such as aluminium salts have existed for long time, but meningitis caused by Neisseria meningitidis serogroups, particularly serogroup B, continues to be a global health problem. Novel strategies have applied in silico and recombinant technologies to develop universal antigens (e.g. proteins, peptides and plasmid DNA) for vaccines, but these antigens have been shown to be poorly immunogenic even when alum adjuvanted, implying a need for better vaccine design. In this work we review the use of natural, detoxified, or synthetic molecules in combination with antigens to activate the innate immune system and to modulate the adaptive immune responses. In the main, antigenic and imune potentiator signals are delivered using nano-, micro-particles, alum, or emulsions. The importance of interaction between adjuvants and antigens to activate and target dendritic cells, the bridge between the innate and adaptive immune systems, will be discussed. In addition, nasal vaccine strategies based on the development of mucosal adjuvants and Neisseria derivatives to eliminate the pathogen at the site of infection provide promising adjuvants effective not only against respiratory pathogens, but also against pathogens responsible for enteric and sexually transmitted diseases(AU)

Inmunización intranasal con AFCo1 induce respuesta inmune de memoria, sistemica y mucosal en ratones neonatal

Neonates have a poorly developed immune system. Respiratory pathogens cause disease during early periods of live. Consequently, it is important to develop protective vaccines that induce immunity and immunological memory against respiratory pathogens early in life. Intranasal (i.n.) route could be an effective via for immunization. Therefore, we explored the effectiveness of AF (Adjuvant Finlay) PL1 (Proteoliposome) from Neisseria meningitidis serogroup B and its derivate Cochleate (AFCo1) by nasal route in neonatal mice. They were immunized i,n, 3 times 7 days apart and anti PL systemic and mucosal antibody response were measured by ELISA. In addition, a prime-boost strategy was used to evaluate the humoral immune response in neonate mice. The 3 doses of AFPL1 or AFCo1 induced significant levels of anti PL IgG antibodies in comparison whit control, but AFCo1 (2017 U/mL) was significantly higher than AFPL1 (1107 U/mL). AFCo1 and AFPL1 induced a predominant Th1 pattern with IgG2a/IgG1 >1 by i,n, immunization and AFCo1 induced a high anti PL IgA saliva response in saliva. Interestingly, one nasally prime at 7 days of born and a memory one boost i,n, dose 9 weeks later with AFCo1 or AFPL1 showed similar specific IgG levels and IgG2a/IgG1 relation than 3 i.n. doses in adult mice. In conclusion, these results represent the first report of neonatal intranasal vaccination using AFCo1 capable to induce systemic and mucosal immunity and priming for memory(AU)

Respuesta inmune mucosal inducida por proteoliposoma y cocleato derivados de N meningitidis serogrupo B

Mucosal vaccination offers attractive advantages to conventional systemic vaccination. Most pathogens enter or establish infection at mucosal surfaces. This represents an enormous challenge for vaccine development. Nevertheless, the availability of safe and effective adjuvants that function mucosally is the major limitation. Therefore, we investigated the impact of mucosal immunization with the Neisseria meningitidis B proteoliposome (AFPL1, Adjuvant Finlay Proteoliposome 1) and its-derived cochleate (Co, AFCo1). They contain multiple PAMPs as immunopotentiators and have delivery system ability as well as Th1 polarization activity. Groups of female mice were immunized by nasal, oral, intravaginal, or intramuscular routes with three doses with AFPL1/AFCo1 alone or containing ovalbumin or glycoprotein (g) D2 from Herpes Simplex Virus type 2 (HSV-2). High levels of specific IgG antibodies were detected in sera of mice vaccinated with either route. However, specific IgA antibodies were produced in saliva and vaginal wash only following mucosal delivering. The polarization to a Th1 pattern was confirmed by testing the induction of IgG2a/IgG2c antibody, positive delayed-type hypersensitivity reactions, and gIFN production. Additionally, AFCo1gD2 showed practically no vaginal HSV-2 replication and 100 percent protection against lethal vaginal HSV-2 challenge. In conclusion, the results support the use of AFCo1 as potent Th1 adjuvant for mucosal vaccines, particularly for nasal route(AU)

Mucosal immunization using proteoliposome and cochleate structures from Neisseria meningitidis serogroup B induce mucosal and systemic responses.

Most pathogens either invade the body or establish infection in mucosal tissues and represent an enormous challenge for vaccine development by the absence of good mucosal adjuvants. A proteoliposome-derived adjuvant from Neisseria meningitidis serogroup B (AFPL1, Adjuvant Finlay Proteoliposome 1) and its derived cochleate form (Co, AFCo1) contain multiple pathogen-associated molecular patterns as immunopotentiators, and can also serve as delivery systems to elicit a Th1-type immune response. The present studies demonstrate the ability of AFPL1and AFCo1 to induce mucosal and systemic immune responses by different mucosal immunizations routes and significant adjuvant activity for antibody responses of both structures: a microparticle and a nanoparticle with a heterologous antigen. Therefore, we used female mice immunized by intragastric, intravaginal, intranasal or intramuscular routes with both structures alone or incorporated with ovalbumin (OVA). High levels of specific IgG antibody were detected in all sera and in vaginal washes, but specific IgA antibody in external secretions was only detected in mucosally immunized mice. Furthermore, antigen specific IgG1 and IgG2a isotypes were all induced. AFPL1 and AFCo1 are capable of inducing IFN-gamma responses, and chemokine secretions, like MIP-1alpha and MIP-1beta. However, AFCo1 is a better alternative to induce immune responses at mucosal level. Even when we use a heterologous antigen, the AFCo1 response was better than with AFPL1 in inducing mucosal and systemic immune responses. These results support the use of AFCo1 as a potent Th1 inducing adjuvant particularly suitable for mucosal immunization.

Purificación de lipopolisacárido de Neisseria meningitidis a partir de unafracción colateral del proceso de producción de VA-MENGOC-BC® / Purification of Neisseria meningitidis lipopolysaccharide starting from a collateral fraction of the process of the antimeningococcal vaccine, VA-MENGOC-BC production process

El trabajo tuvo como objetivo purificar lipopolisacáridos (LPS) de Neisseria meningitidis a partir de una fraccióncolateral del proceso de producción de la vacuna antimeningocócica VA-MENGOC-BC®, el sobrenadante que seobtiene del paso de ultracentrifugación durante el proceso de extracción de las proteínas de la membrana externa delmeningococo. La purificación se realizó mediante precipitación con etanol al 80 por ciento, extracción de las proteínas con fenol al 90 porciento entre 65-70 ºC y ultracentrifugación fraccionada a 105,000 g. Se obtuvieron tres lotes de LPS, en total 1,069 g, con un contenido de proteínas, ácidos nucleicos y ácido sálico respecto al LPS de 0,5 por ciento, 0,3 por ciento y 2,2 por ciento (m/m),respectivamente. La evaluación por cromatografía mostró una alta integridad molecular, con valores de constante de distribución reproducibles (0,36-0,38) y una posible asociación del ácido siálico al LPS. Se apreció homogeneidad en el perfil electroforético de los tres lotes y alta actividad endotóxica. El LPS purificado fue identificado fundamentalmente como del inmunotipo L3,7,9. El procedimiento de purificación empleado permite aprovechar una fracción colateral del proceso de producción de la vacuna, es escalable, no incluye métodos cromatográficos, y posibilita la obtención de gran cantidad de LPS de Neisseria meningitidis, no disponible en el mercado, con elevada pureza y alta actividad endotóxica(AU)

The work aimed at purifying lipopolysaccharides (LPS) of Neisseria meningitidis from a collateral fraction of the antimeningococcal BC vaccine, VAMENGOC-BC®. production process, the supernatant obtained from the ultra centrifugation stage during the proteins extraction process of the meningococcus outer membrane. The purification was carried out by precipitation 80 percent ethanol, protein extraction with 90 percent phenol from 65-70 ºC and fractional ultra centrifugation at 105.000 g. Three lots of LPS were obtained, in total 1.069 g, with a content of proteins, nucleic acids and sialic acid in respect to the LPS of 0.5 percent, 0.3 percent and 2.2percent (m/m) respectively. The assessment by chromatography showed a high molecular integrity. with constant valves of reproducible distribution (Kd 0.36 0.38) and a possible sialic acid association to the LPS. Homogeneitywas observed in the electrophoretic profile of the three lots and a high endotoxic activity. The purified LPS was mainly identified as the inmunotype L3,7,9. The purification procedure used allows making use of a collateral fraction of the vaccine production process, it is scalable, it does not include chromatographic methods and makes easy the obtainment of large quantityof LPS of Neisseria meningitidis, wihich it is non available on the market, with high purity and high endotoxic activity(AU)

Adjuvant properties of lipopolysaccharide from Neisseria meningitidis serogroup B detoxified and conjugated with tetanus toxoid.

We evaluated the adjuvant properties and toxicity of purified Neisseria meningitidis serogroup B lipopolysaccharide (LPS) conjugated with tetanus toxoid (TT) using a new method of conjugation to obtain amine groups in the polysaccharide structure. The endotoxic activity of treated LPS was reduced 2400 times as determined by Limulus amoebocyte assay and no mortality was observed in Balb/c mice inoculated with detoxified LPS versus 100% mortality in native LPS inoculated mice. The conjugated LPS-TT elicited in mice higher anti-TT IgG2a and IgG1 than unconjugated TT. In addition, high levels of anti-LPS IgG and IgG subclasses were detected in sera. These results evidence the adjuvant activity of detoxified LPS and may suggest that the conjugation to TT changes the LPS immune response from thymus-independent to thymus-dependent.

[Skin tests, serum specific IgE and total IgE in the diagnosis of patients with perennial allergic rhinitis]. / Pruebas cutáneas, IgE sérica específica e IgE total en el diagnóstico de pacientes con rinitis alérgica perenne.

BACKGROUND: Skin tests are the most used diagnostic method of allergic rhinitis, which, in addition to identify specific allergen, can determine the relative sensitivity of one patient to the allergen. OBJECTIVE: To assess the association between skin test reactivity and total and specific serum IgE levels on the diagnosis of patients with perennial allergic rhinitis. MATERIAL AND METHODS: We measured the response to skin test reactivity and total and specific serum IgE levels in 69 patients with perennial allergic rhinitis. RESULTS: The skin test reactivity showed responses to: Dermatophagoides pt in 62 patients (90%), house dust in 57 (83%), cat in 41 (59%), dog in 23 (33%), and Lolium p in 16 (23%). The mean level of total IgE was of 378 UI (19 to 4,036) and that of specific IgE was of 39.2 UI (0.2 to 98.6). Total IgE > 200 UI was observed in fifty two patients (75%), which was significantly lesser than the frequency of specific IgE > 0.35 UI (at least for an allergen), which was 94% (p < 0.05, Z). At least two tests of skin reactivity were positive for 90% of the patients. This frequency was similar to the 95% for the specific IgE but different to the 75% for the total IgE (p < 0.05, X2). The correlation between the results of the skin test reactivity and the specific seric IgE showed Spearman r from 0.23 to 0.35 (p < 0.05). The correlation between the total IgE and the specific IgE showed a Spearman r of 0.08 (p < 0.05) and between the total IgE and the skin test reactivity an r of 0.15 (p < 0.05). CONCLUSION: In the diagnosis of perennial allergic rhinitis, the results of the skin test reactivity and the specific serum IgE are correlated but these two results are non consistent with the results of the total serum IgE.

[Allergic dermatitis: new concepts for old diseases]. / Dermatitis alérgicas: nuevos conceptos para viejas enfermedades.

The skin is the largest body's organ, with a well defined functional lymphoid tissue. This organ can be the target of several hypersensitivity-mediated diseases, that are both, genetically determined and influenced by environmental factors. In this paper the main clinical features and the current treatment modalities for the most frequent allergic cutaneous diseases are reviewed.

Validación de un Elisa para la cuantificación de IgG antipolisacárido capsular de neisseria meningitidis serogrupos C en sueros de ratones / Validation of the ELISA for cuantifying capsular anti-polysaccharide IgG of Neisseria meningitidis of the serogroup C in mice sera

Se desarrolló un ensayo inmunoenzimático de fase sólida (ELISA) indirecto para cuantificar anticuerpos IgG específicos antipolisacárido C en ratón, utilizando un prerrecubrimiento con Poli-L-lisina y luego el polisacárido capsular de Neisseria Meningitidis serogrupo C (Instituto Finlay, La Habana, Cuba), para evaluar la respuesta inmune contra este componente en candidatos vacunales en estudios preclínicos. Como conjugado se utilizó anti-IgG ratón conjugado a fosfatasa alcalina, el cual se une a los anticuerpos antipolisacárido C produccidos en ratones...(AU)

Relación entre algunos indicadores de anemia ferripriva y las concentraciones de prealbúmina y transferina sérica / Relationships among some indicators of iron deficiency anemia and serum pre-albumin and transferrin concentrations

Se midieron las concentraciones de pre-albúmina, transferrina, hierro sérico y la capacidad total de fijación de hierro de 45 niños desnutridos, entre 3 meses y 5 años de edad. Se estudió la relación entre estas variables, y se agruparon de acuerdo con los niveles de hemoglobina, para observar mejor la relación de la anemia con los niveles de prealbúmina y transferrina

Relación entre algunos indicadores de anemia ferripriva y las concentraciones de prealbúmina y transferina sérica / Relationships among some indicators of iron deficiency anemia and serum pre-albumin and transferrin concentrations

Se midieron las concentraciones de pre-albúmina, transferrina, hierro sérico y la capacidad total de fijación de hierro de 45 niños desnutridos, entre 3 meses y 5 años de edad. Se estudió la relación entre estas variables, y se agruparon de acuerdo con los niveles de hemoglobina, para observar mejor la relación de la anemia con los niveles de prealbúmina y transferrina

Nitrógeno amínico en sangre, relación nitrógeno ureico/creatinina en orina y algunos indicadores antropométricos en el embarazo / Amide nitrogen in blood, urea nitrogen/creatinine ratio in urine and some anthropometric indicators in pregnancy

Se presetan los valores de dos indicadores del metabolismo proteínico. a) nitrógeno amínico en sangre de la madre y del cordón umbilical y b) relación nitrógeno ureico/creatinina (U/C) en orina de embarazadas clasificadas según peso corporal inicial, aumento de peso durante, la gestación y peso al nacer. Se estudiaron dos grupos de gestantes: uno transversalmente, que fue examinado durante el trabajo de parto, y otro longitudinalmente, examinado una vez cada trimestre. No se observaron diferencias en las concentraciones de nitrógeno amínico en sangre entre los tres trimestres. La variación del peso al nacer (variable dependiente) que podría explicarse por un análisis de regresión que incluye adecuación del peso inicial de la gestante, incremento de peso durante el embarazo, edad materna, nitrógeno amínico en sangre de la madre y del cordón fue de 33,6 por ciento. La proporción de mujeres que tenían valores de U/C por encima del nivel considerado como indeseablemente bajo fue de 85 por ciento. Los resultados sugieren que la retención de nitrógeno, asociada a la síntesis de proteína en el tercer trimestre fue relativamente mayor en las embarazadas y en aquellas cuyos hijos nacieron con más de 3 000 gramos de peso corporal (AU)