Evaluación del desempeño de pruebas diagnósticas de tuberculosis en pacientes VIH positivo en dos hospitales públicos de Bogotá

La tuberculosis TB es una de las principales causas de muerte en el mundo en individuos con infección por VIH. En Colombia esta coinfección soporta una carga importante en la población general convirtiéndose en un problema de salud pública. En estos pacientes las pruebas diagnósticas tienen sensibilidad inferior y la enfermedad evoluciona con mayor frecuencia hacia formas diseminadas y rápidamente progresivas y su diagnóstico oportuno representa un reto en Salud. El objetivo de este proyecto es evaluar el desempeño de las pruebas diagnósticas convencionales y moleculares, para la detección de TB latente y activa pacientes con VIH, en dos hospitales públicos de Bogotá. Para TB latente se evaluó la concordancia entre las pruebas QuantiFERON-TB (QTF) y Tuberculina (PPD), sugiriendo superioridad del QTF sobre la PPD. Se evaluaron tres pruebas diagnósticas por su sensibilidad y especificidad, baciloscopia (BK), GenoType®MTBDR plus (Genotype) y PCR IS6110 teniendo como estándar de oro el cultivo. Los resultados de sensibilidad (S) y especificidad (E) de cada prueba con una prevalencia del 19,4 % de TB pulmonar y extrapulmonar en los pacientes que participaron del estudio fue: BK S: 64% E: 99,1%; Genotype S: 77,8% E: 94,5%; PCRIS6110 S: 73% E: 95,5%, de la misma forma se determinaron los valores predictivos positivos y negativos (VPP y VPN) BK: 88,9% y 94,8%, Genotype S: 77,8% E: 94,5%; PCRIS6110 S: 90% y 95,7%. Se concluyó bajo análisis de curva ROC que las pruebas muestran un rendimiento diagnóstico similar por separado en el diagnóstico de TB en pacientes con VIH, aumentando su rendimiento diagnostico cuando se combinan

Quality improvement of traditional dry fermented sausages based on innovative technological strategies

Dry fermented sausages are highly appreciated food specialties, mainly in Portugal and other southern European countries. Therefore, all research efforts aiming at improving the food quality and safety of traditional dry sausages are of interest, since they are likely to result in products with higher added value and quality standards most suited to the requirements and concerns of the modern consumers. Among those efforts, it may be highlighted the studies involving innovative processing parameters and technologies to overcome practical problems gathered in the meat industry, which are mostly associated with food quality and safety. Additionally, characterization of traditional dry sausages and rationalization of their processing are essential for further achievement of any official certification. Thus, this article attempts to point out some research lines of highest interest in meat science (and particularly to the broad variety of regional dry fermented sausages), towards to the valorisation of technological, nutritional and commercial features. In addition, it is here emphasized the importance for the continuous improvement of the quality and safety of meat products as a way to respond to the current concerns regarding its consumption and the general advices in reducing its daily intake.

Geographical distribution and conservation of Cucurbita in Brazil.

The collection and conservation of the Cucurbita genus in Brazil happened in so dispersed institutions, an assessment of the storage conditions and the genetic diversity is needed, making it possible to identify new priorities for the genus. This work constitutes diagnosis of geographical distribution, storage conditions in situ and ex situ and on genetic diversity of the Cucurbita genus in Brazil. Research was done in herbariums, databases, literature and in situ (expeditions to rural areas and (markets) to map the areas of occurrence of the species. During these expeditions, questionnaires were applied to obtain information about the property and genus Cucurbita. Questionnaires were sent to 173 Brazilian institutions regarding the preservation conditions ex situ. A genetic variability of the Cucurbita genus was found in traditional Brazilian agriculture. Collections must be prioritized in the northern and southern regions (all states); the southeastern region, all states, except Minas Gerais; central-west, in Mato Grosso do Sul and Mato Grosso; the northeastern region, the states of Alagoas, Maranhão, Paraíba, Pernambuco, Piauí and Sergipe. Currently 5.545 entries are being conserved in the Germplasm banks, however, C. pepo, C. ficifolia, C. argyrosperma and wild species are poorly represented. The characterization level of conserved entries is low in the ex situcollections. Participative research projects must be financed as a way to stimulate the farmers to continue planting their local varieties. A coleta e conservação do gênero Cucurbita no Brasil aconteceu de forma dispersa pelas instituições, sendo necessário um diagnóstico sobre as condições de conservação e sobre a diversidade genética, tornando possível identificar novas prioridades para o gênero. Este trabalho realizou diagnóstico sobre distribuição geográfica, condições de conservação in situ e ex situ e sobre diversidade genética do gênro Cucurbita no Brasil. Para mapear as áreas de ocorrência das espécies, foram realizados levantamentos de informações em herbários, banco de dados, literatura e levantamentos in situ (expedições para áreas rurais, feiras livres e CEASAs). Nessas expedições foram aplicados questionários, buscando informações sobre a propriedade e o gênero Cucurbita. Em relação as condições de conservação ex situ, foram enviados questionários para 173 instituições brasileiras. Foi constatado que existe variabilidade genética do gênero Cucurbita na agricultura tradicional brasileira. Devem ser priorizadas coletas nas regiões Norte e Sul (todos os estados); região Sudeste, todos os estados, exceto Minas Gerais; região Centro-Oeste, no Mato Grosso do Sul e Mato Grosso; região Nordeste, os estados de Alagoas, Maranhão, Paraíba, Pernambuco, Piauí e Sergipe. Atualmente estão sendo conservados nos Bancos de Germoplasma 5.545 acessos, no entanto C. pepo, C ficifolia, C. argyrosperma e espécies silvestres estão pouco representadas. É baixa a taxa de caracterização dos acessos conservados nas coleções ex situ. Devem ser financiados projetos de pesquisa participativa como uma forma de estimular e dar condições aos agricultores de continuarem cultivado suas variedades locais.

Geographical distribution and conservation of Cucurbita in Brazil.

The collection and conservation of the Cucurbita genus in Brazil happened in so dispersed institutions, an assessment of the storage conditions and the genetic diversity is needed, making it possible to identify new priorities for the genus. This work constitutes diagnosis of geographical distribution, storage conditions in situ and ex situ and on genetic diversity of the Cucurbita genus in Brazil. Research was done in herbariums, databases, literature and in situ (expeditions to rural areas and (markets) to map the areas of occurrence of the species. During these expeditions, questionnaires were applied to obtain information about the property and genus Cucurbita. Questionnaires were sent to 173 Brazilian institutions regarding the preservation conditions ex situ. A genetic variability of the Cucurbita genus was found in traditional Brazilian agriculture. Collections must be prioritized in the northern and southern regions (all states); the southeastern region, all states, except Minas Gerais; central-west, in Mato Grosso do Sul and Mato Grosso; the northeastern region, the states of Alagoas, Maranhão, Paraíba, Pernambuco, Piauí and Sergipe. Currently 5.545 entries are being conserved in the Germplasm banks, however, C. pepo, C. ficifolia, C. argyrosperma and wild species are poorly represented. The characterization level of conserved entries is low in the ex situcollections. Participative research projects must be financed as a way to stimulate the farmers to continue planting their local varieties. A coleta e conservação do gênero Cucurbita no Brasil aconteceu de forma dispersa pelas instituições, sendo necessário um diagnóstico sobre as condições de conservação e sobre a diversidade genética, tornando possível identificar novas prioridades para o gênero. Este trabalho realizou diagnóstico sobre distribuição geográfica, condições de conservação in situ e ex situ e sobre diversidade genética do gênro Cucurbita no Brasil. Para mapear as áreas de ocorrência das espécies, foram realizados levantamentos de informações em herbários, banco de dados, literatura e levantamentos in situ (expedições para áreas rurais, feiras livres e CEASAs). Nessas expedições foram aplicados questionários, buscando informações sobre a propriedade e o gênero Cucurbita. Em relação as condições de conservação ex situ, foram enviados questionários para 173 instituições brasileiras. Foi constatado que existe variabilidade genética do gênero Cucurbita na agricultura tradicional brasileira. Devem ser priorizadas coletas nas regiões Norte e Sul (todos os estados); região Sudeste, todos os estados, exceto Minas Gerais; região Centro-Oeste, no Mato Grosso do Sul e Mato Grosso; região Nordeste, os estados de Alagoas, Maranhão, Paraíba, Pernambuco, Piauí e Sergipe. Atualmente estão sendo conservados nos Bancos de Germoplasma 5.545 acessos, no entanto C. pepo, C ficifolia, C. argyrosperma e espécies silvestres estão pouco representadas. É baixa a taxa de caracterização dos acessos conservados nas coleções ex situ. Devem ser financiados projetos de pesquisa participativa como uma forma de estimular e dar condições aos agricultores de continuarem cultivado suas variedades locais.

The role of the Rocky Mountains in shaping the atmospheric mean state and the response to tropical forcing in idealised simulations.

Understanding the natural and forced variability of the atmospheric general circulation and its drivers is one of the grand challenges in climate science. It is of paramount importance to understand to what extent the systematic error of climate models affects the processes driving such variability. This is done by performing a set of simulations (ROCK experiments) with an intermediate complexity atmospheric model (SPEEDY), in which the Rocky Mountains orography is increased or decreased to influence the structure of the North Pacific jet stream. For each of these modified-orography experiments, the climatic response to idealized sea surface temperature anomalies of varying intensity in the El Niño Southern Oscillation (ENSO) region is studied. ROCK experiments are characterized by variations in the Pacific jet stream intensity whose extension encompasses the spread of the systematic error found in Coupled Model Intercomparison Project (CMIP6) models. When forced with ENSO-like idealised anomalies, they exhibit a non-negligible sensitivity in the response pattern over the Pacific North American region, indicating that the model mean state can affect the model response to ENSO. It is found that the classical Rossby wave train response to ENSO is more meridionally oriented when the Pacific jet stream is weaker and more zonally oriented with a stronger jet. Rossby wave linear theory suggests that a stronger jet implies a stronger waveguide, which traps Rossby waves at a lower latitude, favouring a zonal propagation of Rossby waves. The shape of the dynamical response to ENSO affects the ENSO impacts on surface temperature and precipitation over Central and North America. A comparison of the SPEEDY results with CMIP6 models suggests a wider applicability of the results to more resources-demanding climate general circulation models (GCMs), opening up to future works focusing on the relationship between Pacific jet misrepresentation and response to external forcing in fully-fledged GCMs.

Trypanosoma Cruzi Strains From Triatomine Collected In Bahia And Rio Grande Do Sul, Brazil.

Collection of triatomines in domestic, peridomestic and sylvatic environments in states of Bahia and Rio Grande do Sul, Northeastern and Southern Brazil respectively, and isolation of Trypanosoma cruzi strains. First, the captured triatomines were identified using insect identification keys, then their intestinal content was examined by abdominal compression, and the samples containing trypanosomatid forms were inoculated in LIT medium and Swiss mice. Six triatomine species were collected in cities in Bahia, namely Panstrongylus geniculatus (01), Triatoma melanocephala (11), T. lenti (94), T. pseudomaculata (02), T. sherlocki (26) and T. sordida (460), and two in cities in Rio Grande do Sul, namely T. circummaculata (11) and T. rubrovaria (115). Out of the specimens examined, T. cruzi was isolated from 28 triatomine divided into four different species: T. melanocephala (one), T. lenti (one), T. rubrovaria (16) and T. sordida (10). Their index of natural infection by T. cruzi was 6.4%. The isolation of T. cruzi strains from triatomines found in domestic and peridomestic areas shows the potential risk of transmission of Chagas disease in the studied cities. The maintenance of those T. cruzi strains in laboratory is intended to promote studies that facilitate the understanding of the parasite-vector-host relationship.

The Consequences Of Refractory Epilepsy And Its Treatment.

Seizures in some 30% to 40% of patients with epilepsy fail to respond to antiepileptic drugs or other treatments. While much has been made of the risks of new drug therapies, not enough attention has been given to the risks of uncontrolled and progressive epilepsy. This critical review summarizes known risks associated with refractory epilepsy, provides practical clinical recommendations, and indicates areas for future research. Eight international epilepsy experts from Europe, the United States, and South America met on May 4, 2013, to present, review, and discuss relevant concepts, data, and literature on the consequences of refractory epilepsy. While patients with refractory epilepsy represent the minority of the population with epilepsy, they require the overwhelming majority of time, effort, and focus from treating physicians. They also represent the greatest economic and psychosocial burdens. Diagnostic procedures and medical/surgical treatments are not without risks. Overlooked, however, is that these risks are usually smaller than the risks of long-term, uncontrolled seizures. Refractory epilepsy may be progressive, carrying risks of structural damage to the brain and nervous system, comorbidities (osteoporosis, fractures), and increased mortality (from suicide, accidents, sudden unexpected death in epilepsy, pneumonia, vascular disease), as well as psychological (depression, anxiety), educational, social (stigma, driving), and vocational consequences. Adding to this burden is neuropsychiatric impairment caused by underlying epileptogenic processes (essential comorbidities), which appears to be independent of the effects of ongoing seizures themselves. Tolerating persistent seizures or chronic medicinal adverse effects has risks and consequences that often outweigh risks of seemingly more aggressive treatments. Future research should focus not only on controlling seizures but also on preventing these consequences.

Oropouche Virus Infection And Pathogenesis Is Restricted By Mavs, Irf-3, Irf-7, And Type I Ifn Signaling Pathways In Non-myeloid Cells.

Oropouche virus (OROV) is a member of the Orthobunyavirus genus in the Bunyaviridae family and a prominent cause of insect-transmitted viral disease in Central and South America. Despite its clinical relevance, little is known about OROV pathogenesis. To define the host defense pathways that control OROV infection and disease, we evaluated OROV pathogenesis and immune responses in primary cells and mice that were deficient in the RIG-I-like receptor signaling pathway (MDA5, RIG-I, or MAVS), downstream regulatory transcription factors (IRF-3 or IRF-7), IFN-β, or the receptor for type I IFN signaling (IFNAR). OROV replicated to higher levels in primary fibroblasts and dendritic cells lacking MAVS signaling, the transcription factors IRF-3 and IRF-7, or IFNAR. In mice, deletion of IFNAR, MAVS, or IRF-3 and IRF-7 resulted in uncontrolled OROV replication, hypercytokinemia, extensive liver damage, and death whereas wild-type (WT) congenic animals failed to develop disease. Unexpectedly, mice with a selective deletion of IFNAR on myeloid cells (CD11c Cre(+) Ifnar(f/f) or LysM Cre(+) Ifnar(f/f)) did not sustain enhanced disease with OROV or La Crosse virus, a closely related encephalitic orthobunyavirus. In bone marrow chimera studies, recipient irradiated Ifnar(-/-) mice reconstituted with WT hematopoietic cells sustained high levels of OROV replication and liver damage, whereas WT mice reconstituted with Ifnar(-/-) bone marrow were resistant to disease. Collectively, these results establish a dominant protective role for MAVS, IRF-3 and IRF-7, and IFNAR in restricting OROV virus infection and tissue injury, and suggest that IFN signaling in non-myeloid cells contributes to the host defense against orthobunyaviruses. Oropouche virus (OROV) is an emerging arthropod-transmitted orthobunyavirus that causes episodic outbreaks of a debilitating febrile illness in humans in countries of South and Central America. The continued expansion of the range and number of its arthropod vectors increases the likelihood that OROV will spread into new regions. At present, the pathogenesis of OROV in humans or other vertebrate animals remains poorly understood. To define cellular mechanisms of control of OROV infection, we performed infection studies in a series of primary cells and mice that were deficient in key innate immune genes involved in pathogen recognition and control. Our results establish that a MAVS-dependent type I IFN signaling pathway has a dominant role in restricting OROV infection and pathogenesis in vivo.

Encephalization And Diversification Of The Cranial Base In Platyrrhine Primates.

The cranial base, composed of the midline and lateral basicranium, is a structurally important region of the skull associated with several key traits, which has been extensively studied in anthropology and primatology. In particular, most studies have focused on the association between midline cranial base flexion and relative brain size, or encephalization. However, variation in lateral basicranial morphology has been studied less thoroughly. Platyrrhines are a group of primates that experienced a major evolutionary radiation accompanied by extensive morphological diversification in Central and South America over a large temporal scale. Previous studies have also suggested that they underwent several evolutionarily independent processes of encephalization. Given these characteristics, platyrrhines present an excellent opportunity to study, on a large phylogenetic scale, the morphological correlates of primate diversification in brain size. In this study we explore the pattern of variation in basicranial morphology and its relationship with phylogenetic branching and with encephalization in platyrrhines. We quantify variation in the 3D shape of the midline and lateral basicranium and endocranial volumes in a large sample of platyrrhine species, employing high-resolution CT-scans and geometric morphometric techniques. We investigate the relationship between basicranial shape and encephalization using phylogenetic regression methods and calculate a measure of phylogenetic signal in the datasets. The results showed that phylogenetic structure is the most important dimension for understanding platyrrhine cranial base diversification; only Aotus species do not show concordance with our molecular phylogeny. Encephalization was only correlated with midline basicranial flexion, and species that exhibit convergence in their relative brain size do not display convergence in lateral basicranial shape. The evolution of basicranial variation in primates is probably more complex than previously believed, and understanding it will require further studies exploring the complex interactions between encephalization, brain shape, cranial base morphology, and ecological dimensions acting along the species divergence process.

Systematics of the neotropical fish subfamily Glandulocaudinae (Teleostei: Characiformes: Characidae)

The systematics of the Glandulocaudinae is reviewed in detail and justification for the recognition of the group as a subfamily is discussed. The subfamily Glandulocaudinae consists of three genera: Lophiobrycon with one species plesiomorphic in some anatomical features but some others exclusively derived relative to the species in the other genera; Glandulocauda with two species intermediate in phylogenetic derivation; and Mimagoniates with seven species (one new), all more phylogenetically derived concerning their pheromone producing caudal-fin organs and with other anatomical characters presumably more derived than in the species of the other genera. Glandulocauda melanogenys Eigenmann, 1911, is considered a junior synonym of Hyphessobrycon melanopleurus Ellis, 1911. A replacement name, Glandulocauda caerulea Menezes & Weitzman, is proposed for G. melanopleura Eigenmann, 1911. Gland cells found in the caudal-fin organs of all species are histologically indistinguishable from club cells and probably secrete a pheromone during courtship. The club cells are associated with somewhat modified to highly derived caudal scales forming a pheromone pumping organ in the more derived genera and species. This subfamily is distributed in freshwaters of eastern and southern Brazil, Paraguay, and northeastern Uruguay.

Geographical and seasonal distributions of the seedeaters Sporophila bouvreuil and Sporophila pileata (aves: Emberizidae)

Many species in the genus Sporophila are migratory. Migration patterns, while poorly studied, may be influenced by seed production which can be very seasonal in some regions. The distribution of S. bouvreuil extends from the Amazon and Suriname south through a large part of the open regions of Brazil. Sporophila pileata, on the other hand, is found in southeastern and southern Brazil as well as Argentina and Paraguay. Both of these species migrate, but their movement patterns are poorly known. To better understand the geographical and the seasonal distributions of S. bouvreuil and S. pileata, we grouped the records into two categories: the breeding season (September to March) and the putative migration season (April to August). We found two areas of sympatry between S. bouvreuil and S. pileata in the Brazilian states of Minas Gerais and São Paulo. For S. bouvreuil we suggest that populations that breed in the Amazon migrate to the Cerrado or Caatinga, where they will encounter resident populations of the same species. These resident populations may take part in short distance migrations. Sporophila pileata, on the other hand, occur in the Cerrado and open areas within the Atlantic Forest and it is not yet possible to determine migratory tendencies or destinations in the non-breeding season.

Genetic-morphometric variation in Culex quinquefasciatus from Brazil and La Plata, Argentina

Variation among natural populations of Culex (Culex) quinquefasciatus Say is associated with different vectorial capacities. The species Cx. quinquefasciatus is present in the equatorial, tropical and subtropical zones in the Brazilian territory, with intermediate forms between Cx. quinquefasciatus and Culex pipiens occurring in regions of latitudes around 33°-35°S. Herein, we studied geographically distinct populations of Cx. quinquefasciatus by genetic characterization and analysis of intra-specific wing morphometrics. After morphological analysis, molecular characterization of Cx. quinquefasciatus and intermediate forms was performed by polymerase chain reaction of the polymorphic nuclear region of the second intron of the acetylcholinesterase locus. Additionally, the morphology of adult female wings collected from six locations was analyzed. Wing centroid sizes were significantly different between some geographical pairs. Mean values of R2/R2+3 differed significantly after pairwise comparisons. The overall wing shape represented by morphometric characters could be divided into two main groupings. Our data suggest that Brazilian samples are morphologically and genetically distinct from the Argentinean samples and also indicated a morphological distinction between northern and southern populations of Brazilian Cx. quinquefasciatus. We suggest that wing morphology may be used for preliminary assessment of population structure of Cx. quinquefasciatusin Brazil

Acupuncture and Temporomandibular Disorders: A 3-Month Follow-up EMG Study

Objectives: The purpose of this study was to investigate the levels of electromyographic (EMG) activation and maximal molar bite force before and after a 3-month acupuncture therapy in individuals with temporomandibular disorder (Helkimo Index) from a pool of subjects attending the Special Care Course of the Ribeirao Preto Dental School, Sao Paulo University, Brazil. Design: All 17 patients, aged between 37 and 50 years (44.2 +/- 4.84 years), with an average weight of 71 +/- 9.45 kg and height of 1.64 +/- 0.07 m, were clinically examined with regard to pain and dysfunctions of the masticatory system. The temporomandibular acupuncture points of needling were IG4, E6, E7, B2, VB14, VB20, ID18, ID19, F3, E36, VB34, E44, R3, and HN3. EMG measures were acquired before and after the treatment using a MyoSystem-BR1 electromyographer. The data collected at rest, protrusion, left and right laterality, and clenching were normalized by maximum voluntary contraction. Maximal bite force in right and left molar regions were registered using a dynamometer with a capacity of up to 1000 N, adapted for oral conditions. The highest value out of three recordings was considered to be the individual's maximal bite force. The results were statistically analyzed using the paired t test (SPSS version 15.0) during the comparison before and after treatment. Results: We found decreased EMG activity at rest, protrusion, left and right laterality, and clenching; as well as increased values of maximal bite force after acupuncture treatment. Conclusions: Acupuncture promoted alterations in the EMG activity of masticatory muscles, increased maximal molar bite force, and led to remission of the subjects' painful symptomatology.

Inequalities in mortality of men by oral and pharyngeal cancer in Barcelona, Spain and Sao Paulo, Brazil, 1995-2003

Background: Large inequalities of mortality by most cancers in general, by mouth and pharynx cancer in particular, have been associated to behaviour and geopolitical factors. The assessment of socioeconomic covariates of cancer mortality may be relevant to a full comprehension of distal determinants of the disease, and to appraise opportune interventions. The objective of this study was to compare socioeconomic inequalities in male mortality by oral and pharyngeal cancer in two major cities of Europe and South America. Methods: The official system of information on mortality provided data on deaths in each city; general censuses informed population data. Age-adjusted death rates by oral and pharyngeal cancer for men were independently assessed for neighbourhoods of Barcelona, Spain, and Sao Paulo, Brazil, from 1995 to 2003. Uniform methodological criteria instructed the comparative assessment of magnitude, trends and spatial distribution of mortality. General linear models assessed ecologic correlations between death rates and socioeconomic indices (unemployment, schooling levels and the human development index) at the inner-city area level. Results obtained for each city were subsequently compared. Results: Mortality of men by oral and pharyngeal cancer ranked higher in Barcelona (9.45 yearly deaths per 100,000 male inhabitants) than in Spain and Europe as a whole; rates were on decrease. Sao Paulo presented a poorer profile, with higher magnitude (11.86) and stationary trend. The appraisal of ecologic correlations indicated an unequal and inequitably distributed burden of disease in both cities, with poorer areas tending to present higher mortality. Barcelona had a larger gradient of mortality than Sao Paulo, indicating a higher inequality of cancer deaths across its neighbourhoods. Conclusion: The quantitative monitoring of inequalities in health may contribute to the formulation of redistributive policies aimed at the concurrent promotion of wellbeing and social justice. The assessment of groups experiencing a higher burden of disease can instruct health services to provide additional resources for expanding preventive actions and facilities aimed at early diagnosis, standardized treatments and rehabilitation.

Internal Residual Stresses in Sintered and Commercial Low Expansion Li(2)O-Al(2)O(3)-SiO(2) Glass-Ceramics

We performed Synchrotron X-ray diffraction (XRD) analyses of internal residual stresses in monolithic samples of a newly developed Li(2)O-Al(2)O(3)-SiO(2) (LAS) glass-ceramic produced by sintering and in a commercial LAS glass-ceramic, CERAN (R), produced by the traditional crystal nucleation and growth treatments. The elastic constants were measured by instrumented indentation and a pulse-echo technique. The thermal expansion coefficient of virgilite was determined by high temperature XRD and dilatometry. The c-axis contracts with the increasing temperature whereas the a-axis does not vary significantly. Microcracking of the microstructure affects the thermal expansion coefficients measured by dilatometry and thermal expansion hysteresis is observed for the sintered glass-ceramic as well as for CERAN (R). The measured internal stress is quite low for both glass-ceramics and can be explained by theoretical modeling if the high volume fraction of the crystalline phase (virgilite) is considered. Using a modified Green model, the calculated critical (glass) island diameter for spontaneous cracking agreed with experimental observations. The experimental data collected also allowed the calculation of the critical crystal grain diameters for grain-boundary microcracking due to the anisotropy of thermal expansion of virgilite and for microcracking in the residual glass phase surrounding the virgilite particles. All these parameters are important for the successful microstructural design of sintered glass-ceramics.