Modifying the Catalytic Activity of Lipopeptide Assemblies with Nucleobases.

Biohybrid catalysts that operate in aqueous media are intriguing for systems chemistry. In this paper, we investigate whether control over the self-assembly of biohybrid catalysts can tune their properties. As a model, we use the catalytic activity of functional hybrid molecules consisting of a catalytic H-dPro-Pro-Glu tripeptide, derivatized with fatty acid and nucleobase moieties. This combination of simple biological components merged the catalytic properties of the peptide with the self-assembly of the lipid, and the structural ordering of the nucleobases. The biomolecule hybrids self-assemble in aqueous media into fibrillar assemblies and catalyze the reaction between butanal and nitrostyrene. The interactions between the nucleobases enhanced the order of the supramolecular structures and affected their catalytic activity and stereoselectivity. The results point to the significant control and ordering that nucleobases can provide in the self-assembly of biologically inspired supramolecular catalysts.

The protometabolic nature of prebiotic chemistry.

The field of prebiotic chemistry has been dedicated over decades to finding abiotic routes towards the molecular components of life. There is nowadays a handful of prebiotically plausible scenarios that enable the laboratory synthesis of most amino acids, fatty acids, simple sugars, nucleotides and core metabolites of extant living organisms. The major bottleneck then seems to be the self-organization of those building blocks into systems that can self-sustain. The purpose of this tutorial review is having a close look, guided by experimental research, into the main synthetic pathways of prebiotic chemistry, suggesting how they could be wired through common intermediates and catalytic cycles, as well as how recursively changing conditions could help them engage in self-organized and dissipative networks/assemblies (i.e., systems that consume chemical or physical energy from their environment to maintain their internal organization in a dynamic steady state out of equilibrium). In the article we also pay attention to the implications of this view for the emergence of homochirality. The revealed connectivity between those prebiotic routes should constitute the basis for a robust research program towards the bottom-up implementation of protometabolic systems, taken as a central part of the origins-of-life problem. In addition, this approach should foster further exploration of control mechanisms to tame the combinatorial explosion that typically occurs in mixtures of various reactive precursors, thus regulating the functional integration of their respective chemistries into self-sustaining protocellular assemblies.

Study of efficacy and longevity of immune response to third and fourth doses of COVID-19 vaccines in patients with cancer: A single arm clinical trial.

Background: Cancer patients show increased morbidity with COVID-19 and need effective immunization strategies. Many healthcare regulatory agencies recommend administering 'booster' doses of COVID-19 vaccines beyond the standard two-dose series, for this group of patients. Therefore, studying the efficacy of these additional vaccine doses against SARS-CoV-2 and variants of concern is of utmost importance in this immunocompromised patient population. Methods: We conducted a prospective single arm clinical trial enrolling patients with cancer that had received two doses of mRNA or one dose of AD26.CoV2.S vaccine and administered a third dose of mRNA vaccine. We further enrolled patients that had no or low responses to three mRNA COVID vaccines and assessed the efficacy of a fourth dose of mRNA vaccine. Efficacy was assessed by changes in anti-spike antibody, T-cell activity, and neutralization activity, which were again assessed at baseline and 4 weeks. Results: We demonstrate that a third dose of COVID-19 vaccine leads to seroconversion in 57% of patients that were seronegative after primary vaccination series. The immune response is durable as assessed by anti-SARS-CoV-2 (anti-S) antibody titers, T-cell activity, and neutralization activity against wild-type (WT) SARS-CoV2 and BA1.1.529 at 6 months of follow-up. A subset of severely immunocompromised hematologic malignancy patients that were unable to mount an adequate immune response (titer <1000 AU/mL) after the third dose and were treated with a fourth dose in a prospective clinical trial which led to adequate immune boost in 67% of patients. Low baseline IgM levels and CD19 counts were associated with inadequate seroconversion. Booster doses induced limited neutralization activity against the Omicron variant. Conclusions: These results indicate that third dose of COVID vaccine induces durable immunity in cancer patients and an additional dose can further stimulate immunity in a subset of patients with inadequate response. Funding: Leukemia Lymphoma Society, National Cancer Institute. Clinical trial number: NCT05016622.

People with cancer have a higher risk of death or severe complications from COVID-19. As a result, vaccinating cancer patients against COVID-19 is critical. But patients with cancer, particularly blood or lymphatic system cancers, are less likely to develop protective immunity after COVID-19 vaccination. Immune suppression caused by cancer or cancer therapies may explain the poor vaccine response. Booster doses of the vaccine may improve the vaccine response in patients with cancer. But limited information is available about how well booster doses protect patients with cancer against COVID-19. Thakkar et al. show that a third dose of a COVID-19 vaccine can induce a protective immune response in half of the patients with cancer with no immunity after the first two doses. In the experiments, Thakkar et al. tracked the immune reaction to COVID-19 booster shots in 106 cancer patients. A third booster dose protected patients for up to four to six months and reduced breakthrough infection rates to low levels. Eighteen patients with blood cancers and severe immune suppression had an inadequate immune response after three doses of the vaccine; a fourth dose boosted the immune response for two-thirds of them, which for some included neutralization of variants such as Omicron. The experiments show that booster doses can increase COVID-19 vaccine protection for patients with cancer, even those who do not respond to the initial vaccine series. Thakkar et al. also show that pre-vaccine levels of two molecules linked to the immune system, (immunoglobin M and the CD19 antigen) predicted the patients' vaccine response, which might help physicians identify which individuals would benefit from booster doses.

Collective adaptability in a replication network of minimal nucleobase sequences.

A major challenge for understanding the origins of life is to explore how replication networks can engage in an evolutionary process. Herein, we shed light on this problem by implementing a network constituted by two different types of extremely simple biological components: the amino acid cysteine and the canonical nucleobases adenine and thymine, connected through amide bonds to the cysteine amino group and oxidation of its thiol into three possible disulfides. Supramolecular and kinetic analyses revealed that both self- and mutual interactions between such dinucleobase compounds drive their assembly and replication pathways. Those pathways involving sequence complementarity led to enhanced replication rates, suggesting a potential bias for selection. The interplay of synergistic dynamics and competition between replicators was then simulated, under conditions that are not easily accessible with experiments, in an open reactor parametrized and constrained with the unprecedentedly complete experimental kinetic data obtained for our replicative network. Interestingly, the simulations show bistability, as a selective amplification of different species depending on the initial mixture composition. Overall, this network configuration can favor a collective adaptability to changes in the availability of feedstock molecules, with disulfide exchange reactions serving as 'wires' that connect the different individual auto- and cross-catalytic pathways.

Retention of Zn, Fe and phytic acid in parboiled biofortified and non-biofortified rice.

Biofortified rice with high Zn concentration could reduce Zn deficiency in South Asia. This population frequently parboils rice. True retention (TR) of Zn, Fe and phytic acid after parboiling and milling was evaluated in biofortified and non-biofortified rice. TR in milled non-parboiled rice was 63.8-89.6% for Zn, 21.1-44.5% for Fe and 16.4-40.3% for phytic acid, whereas in milled parboiled rice TR was 49.8-72.2% for Zn, 23.4-36.7% for Fe and 22.0-33.3% for phytic acid. Milled parboiled rice resulted in lower Zn TR compared to milled non-parboiled. These results suggest that Zn moves from the inner endosperm towards the outer layers during parboiling, regardless of initial Zn concentration, consequently, once milled, the potential impact of Zn intake on Zn deficiency from parboiled rice is less than non-parboiled rice. Despite Zn losses during processing, biofortified rice could provide over 50% of the Zn EAR for children.

Prospective comparative study between two first-line regimens for Helicobacter pylori eradication: Non-bismuth quadruple versus bismuth quadruple therapy / Estudio comparativo prospectivo entre 2 tratamientos de primera línea para la erradicación de Helicobacter pylori: tetraterapia sin bismuto frente a tetraterapia con bismuto

BACKGROUND: The Maastricht V Consensus recommends quadruple therapies as first-line Helicobacter pylori treatment in high clarithromycin (CLA) resistance areas. AIMS: To compare efficacy, side effects and compliance between quadruple concomitant non-bismuth vs bismuth quadruple therapy. METHOD: Prospective study enrolling H. pylori-positive patients. Omeprazol and a three-in-one formulation of bismuth-metronidazol-tetracycline (OBMT-3/1) for 10 days, or combination of omeprazol-clarithromycin-amoxicillin-metronidazol (OCAM) for 14 days, were prescribed. Eradication outcome was assessed by urea breath test or histology. Side effects and compliance were recorded during the treatment period with specific questionnaires. RESULTS: 404 patients were recruited (median age 53 years; 62.87% women). In 382 (183 with OCAM, 199 with OBMT-3/1) the post-treatment test result was available. The eradication rates were 85.94% (CI95%: 80.20-90.52) with OCAM and 88.21% (CI95%: 83.09-92.22) with OBMT-3/1 (p = 0.595) in intention-to-treat analysis, whilst in per protocol analysis they were 91.12% (CI95%: 85.78-94.95) and 96.17% (CI95%: 92.28-98.45) respectively (p = 0.083). Compliance over 90% was 91.35% with OCAM and 92.04% with OBMT-3/1 (p = 0.951). Some side effect was present in 94.02% with OCAM and in 88.89% with OBMT-3/1 (p = 0.109), being longer (12 vs 7 days, p < 0.0001) and more severe (p < 0.0001) with OCAM. CONCLUSIONS: In a high CLA-resistance area, there are no differences between OBMT-3/1 and OCAM in H. pylori eradication and compliance rates, but OBMT-3/1 achieves a higher safety profile

ANTECEDENTES: El Consenso de Maastricht V recomienda tetraterapias como tratamiento de primera línea de Helicobacter pylori en áreas con elevada resistencia a claritromicina (CLA). OBJETIVOS: Comparar la eficacia, los efectos secundarios y el cumplimiento terapéutico entre la tetraterapia sin bismuto y la tetraterapia con bismuto. MÉTODO: Estudio prospectivo que incluyó a pacientes con H. pylori. Se prescribió omeprazol y una formulación 3 en uno de bismuto-metronidazol-tetraciclina (OBMT-3/1) durante 10 días, o una combinación de omeprazol-claritromicina-amoxicilina-metronidazol (OCAM) durante 14 días. El resultado de la erradicación se evaluó mediante una prueba de aliento con urea o histología. Los efectos secundarios y el cumplimiento terapéutico se registraron durante el período de tratamiento empleando cuestionarios específicos. RESULTADOS: Se incluyeron 404 pacientes (mediana de edad de 53 años; un 62,87% de mujeres). El resultado de la prueba posterior al tratamiento estuvo disponible en 382 pacientes (183 con OCAM, 199 con OBMT-3/1). Las tasas de erradicación fueron del 85,94% (IC 95%: 80,20-90,52) con OCAM y del 88,21% (IC 95%: 83,09-92,22) con OBMT-3/1 (p = 0,595) en el análisis por intención de tratar, mientras que en el análisis por protocolo fueron del 91,12% (IC 95%: 85,78-94,95) y del 96,17% (IC 95%: 92,28-98,45), respectivamente (p = 0,083). El cumplimiento terapéutico superior al 90% fue del 91,35% con OCAM y del 92,04% con OBMT-3/1 (p = 0,951). Se observaron efectos secundarios en el 94,02% de los pacientes tratados con OCAM y en el 88,89% de los tratados con OBMT-3/1 (p = 0,109), y fueron más prolongados (12 frente a 7 días, p < 0,0001) y más graves (p < 0,0001) con OCAM. CONCLUSIONES: En un área con elevada resistencia a la CLA no se observan diferencias entre OBMT-3/1 y OCAM en la erradicación de H. pylori ni en las tasas de cumplimiento, pero OBMT-3/1 presenta un perfil de seguridad superior

Prospective comparative study between two first-line regimens for Helicobacter pylori eradication: Non-bismuth quadruple versus bismuth quadruple therapy.

BACKGROUND: The Maastricht V Consensus recommends quadruple therapies as first-line Helicobacter pylori treatment in high clarithromycin (CLA) resistance areas. AIMS: To compare efficacy, side effects and compliance between quadruple concomitant non-bismuth vs bismuth quadruple therapy. METHOD: Prospective study enrolling H. pylori-positive patients. Omeprazol and a three-in-one formulation of bismuth-metronidazol-tetracycline (OBMT-3/1) for 10 days, or combination of omeprazol-clarithromycin-amoxicillin-metronidazol (OCAM) for 14 days, were prescribed. Eradication outcome was assessed by urea breath test or histology. Side effects and compliance were recorded during the treatment period with specific questionnaires. RESULTS: 404 patients were recruited (median age 53 years; 62.87% women). In 382 (183 with OCAM, 199 with OBMT-3/1) the post-treatment test result was available. The eradication rates were 85.94% (CI95%: 80.20-90.52) with OCAM and 88.21% (CI95%: 83.09-92.22) with OBMT-3/1 (p=0.595) in intention-to-treat analysis, whilst in per protocol analysis they were 91.12% (CI95%: 85.78-94.95) and 96.17% (CI95%: 92.28-98.45) respectively (p=0.083). Compliance over 90% was 91.35% with OCAM and 92.04% with OBMT-3/1 (p=0.951). Some side effect was present in 94.02% with OCAM and in 88.89% with OBMT-3/1 (p=0.109), being longer (12 vs 7 days, p<0.0001) and more severe (p<0.0001) with OCAM. CONCLUSIONS: In a high CLA-resistance area, there are no differences between OBMT-3/1 and OCAM in H. pylori eradication and compliance rates, but OBMT-3/1 achieves a higher safety profile.

Iron, Zinc and Phytic Acid Retention of Biofortified, Low Phytic Acid, and Conventional Bean Varieties When Preparing Common Household Recipes.

Biofortification is an effective method to improve the nutritional content of crops and nutritional intake. Breeding for higher micronutrient mineral content in beans is correlated with an increase in phytic acid, a main inhibitor of mineral absorption in humans. Low phytic acid (lpa) beans have a 90% lower phytic acid content compared to conventional beans. This is the first study to investigate mineral and total phytic acid retention after preparing common household recipes from conventional, biofortified and lpa beans. Mineral retention was determined for two conventional, three biofortified and two lpa bean genotypes. Treatments included soaking, boiling (boiled beans) and refrying (bean paste). The average true retention of iron after boiling was 77.2-91.3%; for zinc 41.2-84.0%; and for phytic acid 49.9-85.9%. Soaking led to a significant decrease in zinc and total phytic acid after boiling and refrying, whereas for iron no significant differences were found. lpa beans did not exhibit a consistent pattern of difference in iron and phytic acid retention compared to the other groups of beans. However, lpa beans had a significantly lower retention of zinc compared to conventional and biofortified varieties (p < 0.05). More research is needed to understand the underlying factors responsible for the differences in retention between the groups of beans, especially the low retention of zinc. Combining the lpa and biofortification traits could further improve the nutritional benefits of biofortified beans, by decreasing the phytic acid:iron and zinc ratio in beans.

Programmed Recognition between Complementary Dinucleolipids To Control the Self-Assembly of Lipidic Amphiphiles.

One of the major goals in systems chemistry is to create molecular assemblies with emergent properties that are characteristic of life. An interesting approach toward this goal is based on merging different biological building blocks into synthetic systems with properties arising from the combination of their molecular components. The covalent linkage of nucleic acids (or their constituents: nucleotides, nucleosides and nucleobases) with lipids in the same hybrid molecule leads, for example, to the so-called nucleolipids. Herein, we describe nucleolipids with a very short sequence of two nucleobases per lipid, which, in combination with hydrophobic effects promoted by the lipophilic chain, allow control of the self-assembly of lipidic amphiphiles to be achieved. The present work describes a spectroscopic and microscopy study of the structural features and dynamic self-assembly of dinucleolipids that contain adenine or thymine moieties, either pure or in mixtures. This approach leads to different self-assembled nanostructures, which include spherical, rectangular and fibrillar assemblies, as a function of the sequence of nucleobases and chiral effects of the nucleolipids involved. We also show evidence that the resulting architectures can encapsulate hydrophobic molecules, revealing their potential as drug delivery vehicles or as compartments to host interesting chemistries in their interior.

Neurobiological correlates of state-dependent context fear.

Retrieval of fear memories can be state-dependent, meaning that they are best retrieved if the brain states at encoding and retrieval are similar. Such states can be induced by activating extrasynaptic γ-aminobutyric acid type A receptors (GABAAR) with the broad α-subunit activator gaboxadol. However, the circuit mechanisms and specific subunits underlying gaboxadol's effects are not well understood. Here we show that gaboxadol induces profound changes of local and network oscillatory activity, indicative of discoordinated hippocampal-cortical activity, that were accompanied by robust and long-lasting state-dependent conditioned fear. Episodic memories typically are hippocampus-dependent for a limited period after learning, but become cortex-dependent with the passage of time. In contrast, state-dependent memories continued to rely on hippocampal GABAergic mechanisms for memory retrieval. Pharmacological approaches with α-subunit-specific agonists targeting the hippocampus implicated the prototypic extrasynaptic subunits (α4) as the mediator of state-dependent conditioned fear. Together, our findings suggest that continued dependence on hippocampal rather than cortical mechanisms could be an important feature of state-dependent memories that contributes to their conditional retrieval.

Does smoking influence Crohn's disease in the biologic era? The TABACROHN study.

BACKGROUND: While most studies have found a negative effect of smoking on Crohn's disease (CD) phenotype, more recent data have failed to reproduce this association, which might be due to a current wider use of thiopurines and biologic therapy. The TABACROHN study aimed at defining the impact of smoking on CD in the largest published series. METHODS: This multicenter cross-sectional study included 1170 CD patients. Patients were classified as nonsmokers, current smokers, or former smokers according to their present smoking status. Clinical data regarding disease characteristics, treatment, and complications were collected. RESULTS: Smokers were more frequently under maintenance treatment when compared to nonsmokers. In addition, current smokers presented higher use of biologic drugs compared to nonsmokers. Tobacco exposure and a higher tobacco load were independent predictors of need for maintenance treatment and stenosing phenotype, respectively. CONCLUSIONS: In the era of early and widespread use of immunosuppressants and biologics, tobacco exposure is an independent predictor of need for maintenance treatment, specifically biologic therapy. The wider use of biologics and immunosuppressants could account for the existence of no major differences in disease behavior and complications between nonsmokers and current smokers.

High smoking cessation rate in Crohn's disease patients after physician advice--the TABACROHN Study.

INTRODUCTION: Tobacco smoking has a significant impact on the development of Crohn's disease (CD) and its clinical course, making smoking cessation one of the main goals in CD therapeutic strategy. AIMS: To evaluate the effectiveness of an advice-based smoking cessation strategy among CD patients. METHODS: We have performed a prospective multicenter study which enrolled 408 CD smokers. At inclusion all patients were instructed about the risks of smoking and subsequently followed every 3 months. Each center used additional smoking cessation strategies based on available resources. Urinary cotinine and exhaled carbon monoxide levels were evaluated in a subgroup of patients. RESULTS: Median study follow up was 18 months. 31% of the patients achieved complete smoking cessation and 23% were smoking-free at the end of their follow up with 8% of smoking relapse. Most patients not achieving smoking cessation did not change their smoking habit with only 5% presenting a decrease in tobacco load. 63% of patients willing to quit smoking received help from another specialist, most frequently the pulmonologist (47%). Surprisingly, most patients (88%) tried to quit smoking with no pharmacological therapy and bupropion, varenicline and nicotine replacement treatment were used in few patients. Urinary cotinine and exhaled CO levels tested in a subgroup of patients proved to have a good correlation with the self-reported smoking habit. No predictors of successful smoking cessation were identified. CONCLUSION: Our results underline that an anti-tobacco strategy mostly based on CD patients's education and counseling is feasible and effective in helping patients reach complete abstinence.

Bloqueantes alfa-1 adrenérgicos y síndrome de iris flácido intraoperatorio / Alpha1-adrenogenic blockers and intraoperative floppy iris syndrome

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Pancreatitis crónica idiopática / Idiopathic chronic pancreatitis

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Niveles de ruido en la Unidad de Cuidado Intensivo Neonatal "CIRENA" del Hospital Universitario del Valle, Cali, Colombia / Noise levels in the "Hospital Universitario del Valle" newborn intensive care unit "Cirena", Cali, Colombia

Introducción: Los recién nacidos de alto riesgo requieren tratamiento y cuidados especializados por lo que ingresan en un área exclusiva de la unidad de cuidados intensivos neonatal, Cirena, donde permanecen hospitalizados por largos períodos y son más vulnerables a la exposición de múltiples agresiones físicas y ambientales como el ruido que pueden influir negativamente en su situación clínica y evolución posterior. Objetivo: Determinar los niveles y fuentes de ruido en Cirena del Hospital Universitario del Valle, con el fin de plantear cuidados de enfermería que contribuyan al bienestar del recién nacido. Metodología: Es un estudio descriptivo prospectivo donde se cuantificó la intensidad sonora en diferentes áreas de la unidad, con un sonómetro digital; se identificaron las horas del día y las actividades relacionadas con el incremento de los niveles de ruido en Cirena, según estándares internacionales. El análisis estadístico se efectuó con el programa SPSS versión 11.5. Resultados: Se encontró que los niveles de ruido en Cirena están por encima de lo permitido; el valor máximo registrado fue 73.6 dB y el mínimo 46.5 dB; la principal fuente generadora de ruido fue el personal de la sala. Se requiere sensibilizar a todo el equipo de salud sobre la necesidad de aplicar estrategias para disminuir los niveles de ruido existentes y de esta manera favorecer la reducción del nivel de estrés de los niños hospitalizados.

Introduction: The high risk newborn babies requires special care and treatment then they have to be move to a exclusive area of the new born intensive care unit (Cirena), where they stay in the hospital during long periods of time and they are more vulnerable to multiple physics and environmental aggressions like noise that can make a negative influence on their clinical situation and post evolution. Objective: Determine level and noise levels in the newborn intensive care unit (Cirena), to planning nurse care to make a contribution to the well being of the new born babies. Methodology: This is a prospective descriptive study that quantified the sound intensity in different areas of the unit, with a digital sound meter, the study identifies some hours of the day and the noise increment related activities in CIRENA, according to international standards. The statistic analysis was made with SPSS program V 11.5. Results: The study shows that the CIRENA´s noise level is above of the allowed limit, the maximum registered value was 73.6 dB and the minimum value was 46.5 dB, the main source of noise was the people in the room. All the health team needs to keep in mind that is necessary to apply strategies to decrease the noise level  and in this way, reduce the stress level for kids in the hospital.

Impacto de las Comunicaciones a Congresos Nacionales de Atención Primaria / Impact of Communications to National Primary Care Congresses

Objetivo. Analizar cuántas comunicaciones presentadas en los congresos nacionales de Atención Primaria (CNAP) se publican en revistas indexadas. Diseño. Estudio descriptivo retrospectivo. Emplazamiento y mediciones principales. Fuente de datos: libros de ponencias de los CNAP celebrados en el año 2001; a través del primer autor de la comunicación se buscó en internet [Medline e Índice Médico Español (IME)] si fue publicada, nombre de la revista, idioma, año y diseño del estudio. Resultados. Se presentaron 528 comunicaciones (46,6% orales). Encontramos indexadas en Medline 33 (6,3%) (31 en el congreso de SemFYC y 2 en el congreso de SEMERGEN; p = 0,0001) y en el IME 57 artículos indexados (10,8%). Las revistas que recogen un mayor número de comunicaciones publicadas son Atención Primaria y Semergen; en revistas de lengua inglesa se publicaron 3 artículos. Los estudios descriptivos fueron el diseño más frecuente. Conclusiones. En los CNAP se presentan muchas comunicaciones, aunque se publican pocas, fundamentalmente en las revistas de las Sociedades de Atención Primaria que organizan los congresos

Objective. To determine how many poster and free oral communications accepted by Spanish national primary care congresses are fi nally published in peer review journals as full text articles. Methods. This is a retrospective, descriptive study. We used the abstract books of the Spanish national primary care congresses held in 2001. We selected the free oral and poster communications and using the name of the fi rst author we searched on the Internet (PubMed and the Spanish Medical Index –IME-) for full text publications of these abstracts. We recorded the study design, journal name, language and year of publication of all articles found. Results. A total of 528 of these types of communications (46.6% oral) were accepted by Spanish national primary carecongresses in 2001. We found 33 articles indexed in PubMed (6.3%), 31 were from the SemFYC congress and 2 from the SEMERGEN congress; p=0.0001. On the IME, we found 57 articles (10.8%). The target journals were Atención Primaria and Semergen. We found three articles in English. Descriptive design was the most frequent design in the articles. Conclusions. Although we found numerous free oral and poster communications submitted and accepted by the Spanish national primary care congresses in 2001, it is clear that very fewof these studies become full text publications in peer review journals. These being mainly Spanish language journals