Developments and trends in fruit bar production and characterization.

Fruits serve as a source of energy, vitamins, minerals, and dietary fiber. One of the barriers in increasing fruit and vegetables consumption is time required to prepare them. Overall, fruit bars have a far greater nutritional value than the fresh fruits because all nutrients are concentrated and, therefore, would be a convenience food assortment to benefit from the health benefits of fruits. The consumers prefer fruit bars that are more tasted followed by proper textural features that could be obtained by establishing the equilibrium of ingredients, the proper choosing of manufacturing stages and the control of the product final moisture content. Fruit bar preparations may include a mixture of pulps, fresh or dried fruit, sugar, binders, and a variety of minor ingredients. Additionally to the conventional steps of manufacturing (pulping, homogenizing, heating, concentrating, and drying) there have been proposed the use of gelled fruit matrices, dried gels or sponges, and extruders as new trends for processing fruit bars. Different single-type dehydration or combined methods include, in order of increasing process time, air-infrared, vacuum and vacuum-microwave drying convective-solar drying, convective drying, and freeze drying are also suggested as alternative to solar traditional drying stage. The dehydration methods that use vacuum exhibited not only higher retention of antioxidants but also better color, texture, and rehydration capacity. Antioxidant activity resulting from the presence of phenolic compounds in the bars is well established. Besides this, fruit bars are also important sources of carbohydrates and minerals. Given the wide range of bioactive factors in fresh fruits that are preserved in fruit bars, it is plausible that their uptake consumption have a positive effect in reducing the risk of many diseases.

Temperature increase at the light guide tip of 15 contemporary LED units and thermal variation at the pulpal floor of cavities: an infrared thermographic analysis.

In this study, a comprehensive investigation on the temperature increase at the light guide tip of several commercial light-emitting diode (LED) light-curing units (LCUs) and the associated thermal variation (ΔT) at the pulpal floor of dental cavities was carried out. In total, 15 LEDs from all generations were investigated, testing a quartz-tungsten-halogen (QTH) unit as a reference. The irradiance level was measured with a power meter, and spectral distribution was analyzed using a spectrometer. Temperature increase at the tip was measured with a type-K thermocouple connected to a thermometer, while ΔT at the pulpal floor was measured by an infrared photodetector in class V cavities, with a 1-mm-thick dentin pulpal floor. The relationship among measured irradiance, ΔT at the tip, and ΔT at the pulpal floor was investigated using regression analyses. Large discrepancies between the expected and measured irradiances were detected for some LCUs. Most of the LCUs showed an emission spectrum narrower than the QTH unit, with emission peaks usually between 450 and 470 nm. The temperature increase at the tip followed a logarithmic growth for LCUs with irradiance ≥1000 mW/cm(2), with ΔT at the tip following the measured irradiance linearly (R(2)=0.67). Linear temperature increase at the pulpal floor over the 40-second exposure time was observed for several LCUs, with linear association between ΔT at the pulpal floor and measured irradiance (R(2)=0.39) or ΔT at the tip (R(2)=0.28). In conclusion, contemporary LED units show varied irradiance levels that affect the temperature increase at the light guide tip and, as a consequence, the thermal variation at the pulpal floor of dental cavities.

Influence of photoactivation protocol and light guide distance on conversion and microleakage of composite restorations.

PURPOSE: To evaluate the effect of light guide distance and the different photoactivation methods on the degree of conversion (DC) and microleakage of a composite. METHODS AND MATERIALS: Three photoactivation protocols (600 mW/cm2 x 40 seconds; 400 mW/cm2 x 60 seconds or 200 mW/cm2 x 20 seconds, followed by 500 mW/cm2 x 40 seconds) and three distances from the light source (0, 3 or 7 mm) were tested. Cylindrical specimens (5 mm diameter; 2 mm tall; n=3) were prepared for the DC test (FT-Raman). Class V cavities were made in 90 bovine incisors to conduct the microleakage test. The specimens were conditioned for 15 seconds with phosphoric acid (37%), followed by application of the adhesive system Prime & Bond NT (Dentsply/Caulk). The preparations were restored in bulk. The specimens were stored for 24 hours in distilled water (37 degrees C) before being submitted to the silver-nitrate microleakage protocol. The restorations were sectioned and analyzed under 25x magnification. RESULTS: Statistical analyses (two-way ANOVAs and Tukey test, alpha=0.05) found significance only for the factor distance (p=0.015) at the top of the composite for the DC test. Conversion was statistically lower for the 7 mm groups compared to the 0 and 3 mm groups, which were equivalent to each other. At the bottom of the specimens, none of the factors or interactions was significant (p<0.05). The Kruskal-Wallis test showed that, in general, the soft-start method led to lower microleakage scores when compared to the continuous modes, mainly when associated with a distancing of 7 mm (p<0.01). With the exception of specimens irradiated with 400 mW/cm2 that did not demonstrate variations on scores for the distances tested, higher microleakage was observed for shorter distances from the light source. CONCLUSIONS: Soft-start methods may reduce microleakage when the light guide distancing provides a low level of irradiance, which also causes a discrete reduction in the DC.

Association of HLA-DRB1*16 with chronic discoid lupus erythematosus in Mexican mestizo patients.

BACKGROUND: Chronic discoid lupus erythematosus (CDLE) is present in 15-30% of patients with systemic lupus erythematosus (SLE). Approximately 5% of CDLE cases can evolve to SLE at some stage of the disease. AIM: The aim of this study was to determine gene frequencies of HLA-DRB1 alleles in Mexican mestizo patients with CDLE, irrespective of the presence of systemic disease. METHODS: The study comprised 28 Mexican mestizo patients with CDLE who were attending the Passover Dermatology Centre, in Mexico City. HLA-DRB1 and DQ allele typing was performed by sequence-specific oligotyping after DNA amplification using PCR. The study also included 99 ethnically matched healthy individuals as controls. RESULTS: In the patient group, a significantly increased gene frequency was found for the HLA-DR4 (P = 0.016, OR = 2.24, 95% CI 1.14-4.38) and HLA-DR16 alleles (P = 0.005, OR = 5.51, 95% CI 1.49-21.08). CONCLUSION: HLA-DRB1 alleles seem to be involved in the genetic susceptibility to CDLE in the Mexican mestizo population.

Epidemiologic panorama of stomach cancer mortality in Mexico.

BACKGROUND: Annually, there are more than 6 million deaths from a type of malignant neoplasia worldwide. In developing countries, the highest rates of incidence of malignant neoplasias are uterine cervical cancer, stomach, lung, esophagus, pharynx, and liver cancers. Recent estimates on the incidence of cancer worldwide show that, in 1990, stomach cancer (SC) was the second most frequent type of cancer (900,000 new cases annually). Rates of incidence have decreased consistently in nearly all areas of the world. In Mexico, however, rates of incidence and mortality have increased gradually between 1980 and 1997; in 1995, 4,685 people died of SC in Mexico. This report presents a descriptive analysis of SC mortality in Mexico. METHODS: A mortality database edited from the electronic files of the National Institute of Informatics, Statistics and Geography (INEGI) in Mexico was used; population denominators were edited by the Mexican National Population Council (Conapo). Adjusted mortality rates, taking as standard of reference the population of Mexico City by sex, year, and 10-year age groups were calculated as well as the sex ratio for the 1980-1997 period. To evaluate the magnitude of risks by state, the standardized mortality ratio (SMR) was calculated; prematurity was evaluated through the potential lost-life years index (PLLYI). The analysis was carried out using the Excel and Stata 5.0 software programs. RESULTS: During the years from 1980 to 1997, in Mexico the total number of deaths from SC was 76,315. The male:female ratio was 1.2:1.0. SMR by state showed that the states of Yucatán, Sonora, Zacatecas, Michoacán, and Chiapas had higher mortality rates. The PLLYI was higher for males in the states of Chiapas, Sonora, Chihuahua, Zacatecas, and Southern Baja California, and higher for females in Chiapas, Oaxaca, Yucatán, Puebla, and Campeche. CONCLUSIONS: World statistics on mortality caused by SC suggest a decreasing trend. Findings for this study show an increase in the adjusted mortality rates by SC during the 1980-1997 period in Mexico. However, when analyzing the different indicators that reveal risks, magnitude, and prematurity of mortality, there is a differential trend in mortality by sex that includes regional patterns probably related to different socioeconomic levels.

Class II allele and haplotype frequencies in Mexican systemic lupus erythematosus patients: the relevance of considering homologous chromosomes in determining susceptibility.

The aim of the present study was to determine the relevant major histocompatibility complex (MHC) class II alleles in the genetic susceptibility to systemic lupus erythematosus (SLE) in Mexican Mestizo patients. We examined the gene and haplotype frequencies of the HLA-DRB1, DQA1 and DQB1 alleles by polymerase chain reaction-sequence-specific oligonucleotide probes in 81 Mexican SLE Mestizo patients and 99 ethnically matched controls. We found a significantly increased frequency of the HLA-DRB1*0301 (p(c) = 0.031, odds ratio = 2.63) allele and significantly decreased frequencies of the DRB1*0802 (p(c) = 0.035) and DRB1*1101 (p(c) = 0.037) alleles in the SLE group. Haplotype analysis showed increased frequencies of DRB1*0301-DQA1*0501-DQB1*0201 (p(c) = 0.017, odds ratio = 2.97), and decreased frequency of DRB1*0802-DQA1*0401-DQB1*0402 (p(c) = 0.034) in SLE patients. The most frequently detected haplotypes in SLE patients showed different haplotypic combinations in the homologous chromosome from those found in controls. Thus, the combinations detected in SLE patients were either not detected in the control group or infrequently found. The results suggest that the DRB1*0301 is the principal class II allele associated with the genetic susceptibility to SLE in Mexican patients and that the presence of a specific haplotype of the homologous chromosome in patients with DRB1*0407-DQA1*03-DQB1*0302 and DRB1*1501-DQA1*0102-DQB1*0602 haplotypes could have an additive effect on the susceptibility to the disease. Finally, the low frequency of the DRB1*0301 and DRB1*1501 alleles in the control population suggests that the genetic admixture between Mexican Indians and Caucasian populations was an event that could have increased the risk of Mexicans to develop SLE.

Towards a common framework for clinical trials information systems.

This work describes the strategies for data modeling and implementation and the general architecture of COATI, a Clinical Trials information system that has been in production for more than three years. We discuss how the ICH guidelines influenced the system design, how we used conventional relational and EAV tables and how we integrated third-party software packages into our system. We describe a new architecture that forms the basis of a common framework for Clinical Trials information systems. This structure is based on the concept of a Common Information Framework (CIF). We have defined standard objects and corresponding methods for the CIF as an essential step towards the development of Clinical Trials Informatics.

[Genetic determinant factors of resistance to HIV infection and of control of progression to AIDS: implications on pathogenesis and therapeutic approaches for the eradication of HIV. A review]. / Los factores genéticos determinantes de la resistencia a la infección por VIH y del control de la progresión al SIDA: implicaciones sobre la patogénesis y las estrategias terapéuticas para la erradicación del VIH. Una revisión.

In this review, we describe and discuss the genetic factors that, up to some point, determine resistance to the infection and control the progression of the disease in HIV-infected individuals. Genetic factors may account for non-progression or slow progression of the disease in some of so called long-term non progressors HIV-infected individuals. In general, this group shows no symptoms for more than 10 years, while their circulating T CD4+ cells levels remain stable and they usually have a low virus load. Even though non-progression and rapid progression phenomenon are still not fully understood, there probability exists that some class I and class II MHC alleles are associated with a greater or smaller risk to develop AIDS. Class I HLA-B*35 and Cw*04 alleles are the ones commonly associated with the rapid transition of the infection into AIDS. In contrast, heterozygosity for class I HLA alleles and, particularly, the absence of HLA-B*35 and Cw*04 may contribute to non-progression. Studies which set forward other HLA alleles as possibly taking part of the pathogenic mechanism of non-progression are also described; although, relevant methodological problems can be noticed. Furthermore, this review explains and discusses allelic variations for some of the components of the chemokine receptors family, particularly the genes which codify for CCR5 and CCR2 and other genetic factors such as the SDF1-3'. A variant of the alpha SDF1 chemokine gene that have been associated with AIDS' slow progression or non-progression in HIV-infected individuals. As a whole, the factors described in this review are those that influence the natural history of the disease due to HIV and give an example of what genetic or multigenetic influence can have over the pattern of evolution of HIV infection. Finally, we mention the possible implications that the identification of the genetic markers has in the pathogenesis of HIV disease and in the development of the new therapeutic strategies to control or eliminate HIV.

Lack of association between the polymorphism at the heat-shock protein (HSP70-2) gene and systemic lupus erythematosus (SLE) in the Mexican mestizo population.

Major histocompatibility complex (MHC) alleles have been recognized as genetic factors for developing systemic lupus erythematosus (SLE). In the present study we analyzed whether a heat-shock protein gene (HSP70-2) is involved in determining susceptibility to develop SLE in a Mexican Mestizo population. A HSP70-2 Pst I polymorphism was detected by a restriction fragment length polymorphism analysis of polymerase chain reaction (PCR-RFLP) in 107 SLE patients and 158 healthy controls. No statistically significant differences were observed in the HSP70-2 allele distribution between patients and healthy controls. HLA-DR analysis showed an increased frequency of HLA-DR3 allele in the patients group (P < 0.05, OR = 2.26, EF = 6.0%). On the other hand, when we analyzed HSP70-2 polymorphism in relation to HLA-DR3 allele, we could only detect an increased frequency of AB genotype in the DR3 negative patients (pC < 0.05, RR = 2.6, EF = 11.3%). Linkage disequilibrium was observed for three haplotypes: HLA-DR3-HSP70-2A (D = 0.03, D' = 0.67, P < 0.01); HLA-DR1-HSP70-2A (D = 0.03, D' = 0.86, P < 0.01) and HLA-DR8-HSP70-2B (D = 0.02, D' = 0.46, P = 0.02). Our data indicate that HSP70-2 gene polymorphism as opposed to the other ethnic groups does not appear to be relevant in SLE susceptibility in Mexican patients and that the distribution of the different alleles depend on the frequency of HLA alleles associated with them.

HLA genes in Mexican Mazatecans, the peopling of the Americas and the uniqueness of Amerindians.

The HLA allele frequency distribution of the Mexican Mazatecan Indians (Olmec culture) has been studied and compared with those of other First American Natives and worldwide populations (a total of 12,100 chromosomes; 6,050 individuals from 59 different populations). The main conclusions are: 1) An indirect evidence of Olmec and Mayan relatedness is suggested, further supporting the notion that Olmecs may have been the precursors of Mayans; 2) Language and genetics do not completely correlate in microenvironmental studies; and 3) Peopling of the Americas was probably more complex than postulated by Greenberg and others (three peopling waves). Significant genetic input from outside is not noticed in Meso and South American Amerindians according to the phylogenetic analyses; while all world populations (including Africans, Europeans, Asians, Australians, Polynesians, North American Na-Dene Indians and Eskimos) are genetically related. Meso and South American Amerindians tend to remain isolated in the Neighbor-Joining, correspondence and plane genetic distance analyses.

A database system for integrated clinical trial management, control, statistical analysis and ICH-compliant reporting.

Clinical trial management and quality assurance is a complex activity that, when manually executed, is prone to errors and delays, and organizations involved in the conduct of clinical drug trials must rely on database systems to ensure adequate data integrity and timely reporting. We report the design and implementation of an integrated computer system for the management and control of multiple phase II to IV clinical drug trials, and for automated generation of monitoring and statistical analysis reports that are fully compliant with international guidelines. This Windows-based system incorporates a number of third-party software tools and applications, and its major components are COATI (Control, Assessment and Tracking of Therapeutic Investigations), a client-server database application; DART (Data Analysis and Reporting Tool) for automated data abstraction and reporting; and PANDA (Data Analysis Package) for automated statistical analysis. The system is in production for two years and was used in 15 clinical trials in a diversity of medical conditions and study designs.

Heat-shock protein (HSP70-2) allelic frequencies in three distinct Mexican populations.

The major histocompatibility complex (MHC) genes are highly polymorphic and therefore have been useful in population genetics and disease association studies. We analyzed restriction fragment length polymorphism of HSP70-2 alleles in healthy unrelated Mestizo, Mazatecan and Nahua populations. Both Indian groups, Mazatecans and Nahuas, were in Hardy-Weinberg equilibrium, while Mestizos were in disequilibrium (chi 2 = 0.399; P < 0.05). The Mazatecan Indians presented a high frequency of BB homozygosity (17.35%) compared to Mestizos (5%) (P = 0.01). Mexican ethnic groups present differences in distribution of BB genotype. The low frequency of BB genotype in Mestizos may be the result of a negative selection process.

Intron 2 and exon 3 sequences may be involved in the susceptibility to develop Takayasu arteritis.

We studied Major Histocompatibility Complex (MHC) Class I and Class II genes in seven Mexican Mestizo patients with Takayasu arteritis. Takayasu arteritis is an uncommon condition in Mexican Mestizo, however, previous studies report association of the disease in this population with Human Leukocyte Antigen (HLA)-B39 and HLA-DRB1*1301. The results in the present study show that the haplotypes of the Mexican Mestizo patients with Takayasu arteritis are very heterogeneous, even when the disease is much more rare in Mexico than in Japan. The sequence analysis of HLA-B39 shows that Mexican patients exhibit the HLA-B*39061 and HLA-B*39062 subtypes. These subtypes are more common in Mexico than in Japan, where the predominant subtype is HLA-B*3901. Interestingly, HLA-B*39061 and B-39062 share the 3' end of intron 2 and the 5' end of exon 3 with HLA-B*5101 and B*52012, alleles associated to Takayasu arteritis in Japanese. This fact suggests that Takayasu arteritis patients may share a specific sequence rather than a specific allele, even when the gene involved in the susceptibility to develop Takayasu arteritis may be a neighboring gene located between the genes related at present time with the disease, i.e. a gene located between MHC Class I and Class II regions.

A unified approach to the design of clinical reporting systems.

Computer-based Clinical Reporting Systems (CRS) for diagnostic departments that use structured data entry have a number of functional and structural affinities suggesting that a common software architecture for CRS may be defined. Such an architecture should allow easy expandability and reusability of a CRS. We report the development methodology and the architecture of SISCOPE, a CRS originally designed for gastrointestinal endoscopy that is expandable and reusable. Its main components are a patient database, a knowledge base, a reports base, and screen and reporting engines. The knowledge base contains the description of the controlled vocabulary and all the information necessary to control the menu system, and is easily accessed and modified with a conventional text editor. The structure of the controlled vocabulary is formally presented as an entity-relationship diagram. The screen engine drives a dynamic user interface and the reporting engine automatically creates a medical report; both engines operate by following a set of rules and the information contained in the knowledge base. Clinical experience has shown this architecture to be highly flexible and to allow frequent modifications of both the vocabulary and the menu system. This structure provided increased collaboration among development teams, insulating the domain expert from the details of the database, and enabling him to modify the system as necessary and to test the changes immediately. The system has also been reused in several different domains.

Modification of the OMED nomenclature: a system approach based on the SISCOPE data model.

The OMED nomenclature represented a turning point in endoscopic computer systems by supplying software developers with an internationally recognized scientific document on which prototypes could be based. The main pitfalls of the OMED system are related to its hierarchical structure, probably not the most effective design to represent endoscopic findings. Based on our experience during the development of SISCOPE, an integrated data management system for endoscopy, an alternative scheme is proposed: Endoscopic descriptions are modeled as a set of objects represented by a data structure whose elements are location, morphology, associated lesions and hemorrhage. 72 objects appear to be sufficient for an accurate representation of all endoscopic scenes and a consistent data model could be created with this approach. Efforts should be made to decrease redundancy in the OMED nomenclature, but extension to other endoscopic data types, such as clinical and pathological diagnosis, is more urgently required. Furthermore, if data exchange between systems is desired, the definition of an Endoscopy Metafile is an absolute requirement.

Longitudinal comparative study on the influence of computers on reporting of clinical data.

The impact of the clinical database system SISCOPE on medical services was evaluated and objective data compiled on the quality of information recording and reporting using a fully structured data entry system compared to traditional free text reporting. 1565 upper endoscopy reports produced with SISCOPE over a period of 12 months were assessed for completeness and compared to 152 and 208 free text reports done 4 months before and 1 month after the study period, respectively. Data on four common gastrointestinal findings (esophageal varices, ulcers, polyps and tumors) were evaluated. Physicians' compliance with the new system was good, as reflected by a constant level of quality of reporting over time, although a very slight decline in the ratio of computer generated reports to the total number of examinations was noted. Structured reports had an 18% missing data rate and contained 60% more relevant information than free text reports, which had a 48% missing data rate. No educational effect of the system was seen as missing data rates returned to pre-computerization levels just one month after the end of the study. It is concluded that menu-driven structured data entry systems result in production of far superior reports as compared to free text systems, probably due to their reminder effect.