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BACKGROUND: Incisional biopsy is indicated for intraoral tumors, but it is a contraindicated surgical procedure for major salivary glands. To avoid complications and facilitate diagnosis, fine needle aspiration biopsy (FNAB) is a type of biopsy widely used for preoperative diagnosis in these glands. MATERIAL AND METHODS: The aim of this study was to analyze the agreement between the diagnosis by FNAB (major glands), incisional biopsy (minor glands) and histopathological analysis of the surgical specimen in salivary gland tumors from a database (medical records) of patients treated in a cancer treatment reference center in the Northeast region of Brazil. RESULTS: The sample consisted of 110 cases, being 86 of them malignant tumors in major salivary glands (parotid gland=73; submandibular gland=13) and 24 cases in minor salivary glands (palate). The female gender was the most affected (57.3%), especially in patients over 60 years (42.7%). In the TNM classification, 41.8% of the cases were in T2 at the time of diagnosis, with most of the regional lymph nodes in N0 (85.5%) and 87.3% of the cases in M0. FNAB was able to identify malignant neoplasms in 68.6% of the cases (n=59), while incisional biopsy in palatal tumors obtained agreement of 75% of the cases (n=18). The analysis revealed that tumors classified as T3-T4 (p=0.012) showed greater agreement between pre- and post-surgical diagnosis. CONCLUSIONS: The results obtained in this study indicate that FNAB has similar accuracy to incisional biopsy in providing satisfactory preoperative diagnoses of malignant tumors in salivary glands.

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The aim of this study was to investigate the immunohistochemical expression of REGγ, p53, MDM-2, Bcl-2, and Bax in oral tongue squamous cell carcinoma (OTSCC), and to correlate the findings with clinicopathological parameters. Fifty-eight OTSCC cases were selected for the study. The percentages of nuclear (REGγ, p53, and MDM-2) and cytoplasmic (Bcl-2 and Bax) staining in epithelial cells were determined and correlated with clinicopathological parameters (regional lymph node metastasis, clinical stage, clinical outcome, and histopathological grade of malignancy). Expression of REGγ was observed in all cases studied. Significantly lower percentages were observed in tumours with lymph node metastasis (P = 0.036) and in high-grade tumours (P = 0.013). No significant differences in p53, MDM-2, or Bax expression were observed according to the clinicopathological parameters. Lower percentages of Bcl-2 staining were found in high-grade OTSCC (P = 0.040) and in cases of disease-related death (P = 0.032). The expression of REGγ showed a weak positive correlation with the expression of MDM-2 (P = 0.001) and Bcl-2 (P = 0.014). The results of this study suggest that lower expression of REGγ may contribute to the progression of OTSCC. The role of REGγ in the development of OTSCC does not appear to be primarily related to the modulation of apoptosis in neoplastic cells.

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BACKGROUND: Dermoid and epidermoid cysts are slow-growing, benign developmental cysts that arise from ectodermal tissue and can occur anywhere in the body. Less than 7% of these cysts involve the head and neck region, with only 1.6% of cases presenting in the oral cavity. To evaluate the clinical and histopathological features of dermoid (DCs) and epidermoid (ECs) cysts stored in the archives of a referred Oral Pathology Service over a 48-year-period, and to review current concepts about these cysts. MATERIAL AND METHODS: All DCs and ECs were reviewed, and clinical data were obtained from the patient records. Fourteen cases of DCs and thirteen cases of ECs were re-evaluated microscopically by 2 oral pathologists. RESULTS: Among 15.387 cases, 14 (0.09%) had a histopathological diagnosis of DCs and 13 (0.08%) of ECs. For DCs, ten (71.4%) patients were women, with the mean age of 37.2 years. All DCs were lined by a stratified squamous epithelium (100%), with gut and respiratory epithelium observed in 1 (7.1%) and 2 (14.3%) cases, respectively. Chronic inflammatory cells, melanin, multinucleated giant cell reaction, and Pacini bodies were also observed. For ECs, eight (61.5%) cases were in women, and the mean age was 38.2 years. All ECs were lined by a stratified squamous epithelium (100%). Chronic inflammatory cells, melanin pigmentation, and adipose tissue were observed in the fibrous capsule. CONCLUSION: Our results suggest that stratified squamous epithelium is the predominant epithelial lining of these cystic lesions. Also, we may find some unusual findings in DCs, such as Pacini bodies.

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BACKGROUND: Oral potentially malignant disorders (OPMDs) comprise a range of clinical-pathological alterations that are frequently characterized as architectural and cytological derangements upon histological analysis. Epithelial-mesenchymal transition (EMT) has been proposed as a critical mechanism for the acquisition of the malignant phenotype in neoplastic epithelial processes. This study aims to systematically review the current findings on the immunohistochemical expression of epithelial-mesenchymal transition markers in oral potentially malignant disorders and to evaluate their possible application as biomarkers associated with the progression of oral epithelial dysplasias. MATERIAL AND METHODS: A systematic search was performed in the following databases: PubMed, EMBASE, Chinese BioMedical Literature Database, and Cochrane Library. Articles that evaluated the relationship between the expression of EMT markers and the degree of oral epithelial dysplasia were selected for the systematic review. The quality of each eligible study was evaluated by independent reviewers that used operationalized prognostic biomarker reporting guidelines (REMARK). RESULTS: Seventeen articles met all inclusion criteria and were selected. The EMT markers analyzed exhibited an important association with the prognosis of the cases evaluated. The results showed a progressive increase in the expression of nuclear transcription factors and markers of mesenchymal differentiation, as well as negative regulation of epithelial and cell adhesion markers, according to the stage of oral epithelial dysplasia. CONCLUSIONS: The dysregulation of expression of important EMT components in oral dysplastic epithelium is a potential prognostic marker in OPMDs.

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BACKGROUND: Odontogenic keratocyst (OKC) is an odontogenic developmental cyst that presents distinct clinical behavior. This lesion has been described as dental cysts with keratinization since the 1930s, however the term OKC was established in 1956. This study aims to determine the frequency and features of OKC in children aged 0 to 14 years in an oral pathology service in Brazil. MATERIAL AND METHODS: A retrospective study was performed to review cases of OKC in children diagnosed between 1986 and 2017. Clinical data were evaluated from medical records (gender, race, age, anatomical location, treatment, radiographic findings and follow-up). RESULTS: Ninety-seven cases of OKC were diagnosed in a 31-year-period in all age groups and 10 were found in children (10.3%). Age ranged from 2 to 14 years (mean age=10.5±3.5), with 8 males and 2 females. The most frequent location was the anterior region of the mandible (n=4). Patients were predominantly asymptomatic. Moreover, in two children, clinical findings of Gorlin-Goltz Syndrome were observed. The most commonly used treatment was enucleation followed by curettage. In all cases of Gorlin-Goltz Syndrome were observed recurrences and occurrence of new keratocysts. CONCLUSION: Although uncommon in pediatric patients, OKC should be considered a differential diagnosis in cases of osteolytic lesions in gnathic bones. Thus, the periodic assessment of children by dentists and pediatricians is essential to get a correct diagnosis and early treatment to avoid greater mutilation of these patients.

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BACKGROUND: Yeasts of the Candida genus are one of the most common causes of bloodstream infections associated with high rates of morbidity and mortality, mainly affecting immunocompromised patients. We aimed to identify yeasts obtained from blood cultures of patients interned at tertiary hospitals in Brazil. METHODS: We evaluated some of the major virulence factors of Candida spp., including the ability to adhere to human buccal epithelial cells, biofilm formation, hemolytic and phospholipase activity. RESULTS: We analyzed 70 isolates of Candida spp. obtained from March 2011 and March 2015. Candida spp. showed different peculiarities in terms of expression of virulence factors evaluated in vitro. C. albicans strains were more adherent to HBEC than all the other Candida species. C. tropicalis strains were considered strong biofilm producers. Strains belonging to the C. parapsilosis species complex were able to produce hemolysins, while C. glabrata was also able to lyse erythrocytes and to produce phospholipase. CONCLUSION: These results suggest that Non-Candida albicans Candida species are also able to express virulence factors which play an important role in bloodstream infectious caused by these yeasts.

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BACKGROUND: Odontogenic tumors (OTs) are uncommon neoplastic lesions of the maxilla and mandible, which present difficult diagnosis and therapeutics. This paper aims to determine the frequency and distribution of OTs, over a period of 22 years, at a public university in Northeastern Brazil. MATERIAL AND METHODS: We reviewed all cases of OTs from oral pathology laboratory of Federal University of Rio Grande do Norte (UFRN), from 1996 to 2017. The tumors were classified according to the latest (2017) World Health Organization Classification of Tumors. Data on age, gender, anatomic site, symptomatology, radiographic findings and tumor size were analyzed. RESULTS: In the analyzed period, 247 cases of OTs were diagnosed. Epithelial tumors were more common with 127 cases (51.8%). The most common tumors were ameloblastoma (n = 112 / 45.4%), odontoma (n = 89 / 36.1%) and odontogenic myxoma (n = 17 / 6.9%). Malignant odontogenic tumors were extremely rare in the studied population with only 2 cases (0.8%) of diagnosed carcinomas. These tumors were diagnosed in a wide age range, from 5 to 81 years, being more common in the second and third decades of life. In general, the mandible was the most affected anatomic site (n = 162/66%) and the mandible:maxilla ratio was of 2:1. Ameloblastoma was the tumor with the highest number of symptomatic cases (n = 26) and with the highest mean size (cm) with 4.5cm. CONCLUSIONS: Odontogenic tumors were rare in the sample studied (2.2%), with ameloblastoma and odontoma being the most common tumors. Continuous studies that show the characteristics of these lesions are fundamental, especially after modifications in the international classification.

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BACKGROUND: Early detection of oral cancer is the most effective means of reducing morbidity, complexity, and extent of treatment. This study evaluated the clinicopathological profile of epidermoid carcinoma of the tongue, including treatment and survival. MATERIAL AND METHODS: This observational, retrospective cross-sectional study evaluated patients with squamous cell carcinoma of the tongue treated at the Dr. Luiz Antônio Hospital, Natal, Brazil, from January 2001 to December 2011. Survival variables were calculated using the Kaplan-Meier method and compared by log rank tests. RESULTS: Of the 412 patients diagnosed in this period, 298 (72.3%) were men; their mean age was 60.5 years, and 69.2% were diagnosed with stage III/IV tumours. Improved survival was associated with early stage diagnosis, absence of affected lymph nodes at diagnosis, and treatment with surgery alone. CONCLUSIONS: Late stage diagnosis of oral cancer negatively affects patient survival. In addition, the general public should be made aware of the prognostic factors for oral SCC of the tongue and of the importance of periodic examinations of the oral cavity.

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Abstract Aquatic macrophytes have properties and mechanisms which are useful for the removal of substances in solution, commonly used in phytoremediation processes in aquatic environments. This study evaluated the performance of copper (Cu) accumulation by Salvinia biloba Raddi (Salviniaceae) in different metal concentrations (1, 3 and 5 µg mL-1), as well as the control treatment, measured at intervals of 0, 7 and 14 days under laboratory conditions, with control as to pH and luminosity. After the experiment, the S. biloba biomass was washed, kiln dried, crushed and subjected to the process of digestion, and subsequently the accumulated copper content was determined by atomic absorption spectroscopy. The results showed that S. biloba is apt at accumulating copper, varying significantly between different treatments and days of exposure to the contaminant, as well as its interaction (treatment × days). The highest accumulation values were observed in treatment with 5 µg mL-1, which at 14 days, with 11,861 µg g-1 of copper. We observed symptoms of toxicity and mortality in plants, probably indicating the effect of copper on the species when at high levels. Salvinia biloba is an efficient species in the removal of copper in solution, its recommendation as a remediating agent in aquatic ecosystems being possible.

Resumo Macrófitas aquáticas apresentam propriedades e mecanismos úteis à remoção de substâncias presentes em solução, comumente, utilizadas em processos de fitorremediação de ambientes aquáticos. Este estudo avaliou o desempenho de acumulação de cobre (Cu) por Salvinia biloba Raddi (Salviniaceae) em diferentes concentrações do metal (1, 3 e 5 µg mL-1), além do tratamento controle, avaliados em intervalos de 0, 7 e 14 dias, sob condições laboratoriais, com controle de pH e luminosidade. Após o experimento a biomassa de S. biloba, foi lavada, seca em estufa, triturada e submetida ao processo de digestão, sendo, posteriormente, o teor de cobre acumulado determinado por espectroscopia de absorção atômica. Os resultados evidenciaram que S. biloba é hábil em acumular cobre em sua biomassa, variando significativamente entre os diferentes tratamentos e dias de exposição ao contaminante, bem como por sua interação (tratamentos × dias). Os maiores teores de acúmulo foram observados no tratamento com 5 µg mL-1, que aos 14 dias apresentou até 11.861 µg g-1 de Cu. Observamos sintomas de toxicidade e mortalidade nas plantas, evidenciando, provavelmente, o efeito do cobre sobre a espécie quando em elevados níveis. Salvinia biloba é uma espécie eficiente na remoção do cobre em solução, sendo possível sua recomendação como agente de remediação em ecossistemas aquáticos.

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BACKGROUND: the objective of this study was to describe the frequency of cystic lesions in a Brazilian population of patients histopathologically diagnosed in the first and second decade of life. MATERIAL AND METHODS: Retrospective descriptive cross-sectional study was performed. Biopsy records were obtained from the archives of a Brazilian referral center between 1980 and 2016. RESULTS: A total of 2.114 biopsy records of pediatric patients were analyzed with oral and maxillofacial lesions. Data such as gender, age, anatomical location, and histopathological diagnosis were collected and categorized. Among all oral and maxillofacial lesions (n=2.114), were diagnosed 294 cases of odontogenic cysts (13.9%) and 16 cases of non-odontogenic cysts (0.8%). The most frequent lesions in each group were, respectively: radicular cyst (n=145) and epidermoid cyst (n=4). These lesions were most common in female (n=158), with a mean age of 14 years. For intraosseous lesions, the mandible (n=148) was the most affected anatomic site; moreover, the floor of the mouth (n=6) was most affected by cysts in soft tissues. CONCLUSIONS: Odontogenic cysts were relatively common in population studied, but non-odontogenic cysts were rare in these patients.

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Aquatic macrophytes have properties and mechanisms which are useful for the removal of substances in solution, commonly used in phytoremediation processes in aquatic environments. This study evaluated the performance of copper (Cu) accumulation by Salvinia biloba Raddi (Salviniaceae) in different metal concentrations (1, 3 and 5 µg mL-1), as well as the control treatment, measured at intervals of 0, 7 and 14 days under laboratory conditions, with control as to pH and luminosity. After the experiment, the S. biloba biomass was washed, kiln dried, crushed and subjected to the process of digestion, and subsequently the accumulated copper content was determined by atomic absorption spectroscopy. The results showed that S. biloba is apt at accumulating copper, varying significantly between different treatments and days of exposure to the contaminant, as well as its interaction (treatment × days). The highest accumulation values were observed in treatment with 5 µg mL-1, which at 14 days, with 11,861 µg g-1 of copper. We observed symptoms of toxicity and mortality in plants, probably indicating the effect of copper on the species when at high levels. Salvinia biloba is an efficient species in the removal of copper in solution, its recommendation as a remediating agent in aquatic ecosystems being possible.

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The purpose of this study was to evaluate the immunoexpression of vascular endothelial growth factor C (VEGF-C) and VEGF receptor 3 (VEGFR-3) and their correlation with intratumoural lymphatic density (ILD) and peritumoural lymphatic density (PLD) in metastatic and non-metastatic lower lip squamous cell carcinoma (LLSCC). Twenty-five LLSCC with regional nodal metastasis and 25 LLSCC without metastasis were selected. The percentages of VEGF-C and VEGFR-3 staining in each tumour core and at the deep invasive front were assessed. PLD and ILD were determined using anti-podoplanin antibody. Immunohistochemical findings were correlated with nodal metastasis, clinical staging, local recurrence, clinical outcome, and histological grade. Cytoplasmic immunoexpression of VEGFR-3 in the tumour core was associated with metastasis (P=0.009), patient death (P=0.008), and histological grade (P<0.005). PLD, ILD, and VEGF-C expression showed no significant associations with clinicopathological parameters (P>0.05). PLD and ILD were not significantly correlated with the immunoexpression of VEGF-C or VEGFR-3 (P>0.05). There was a significant positive correlation between PLD and ILD (P=0.004), and between cytoplasmic immunoreactivity of VEGF-C and VEGFR-3 (P=0.011). These results suggest an important role for VEGFR-3 in the progression of LLSCC, and highlight the possible influence of its expression on the prognosis of these tumours. ILD and PLD may not be associated with lymph node metastasis in LLSCC.

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Elephant grass is a tropical forage plant widely distributed throughout Brazil. It was first exclusively used in the livestock sector as cattle feed. The grass is characterized by its high productivity and photosynthetic capacity and is considered as an alternative source of renewable energy. Here, we estimated the general combining ability of the parents and specific combining ability of the hybrids based on morpho-agronomic biomass-quality traits. The experiment was conducted in a randomized block design with 3 replicates. The diallel was composed of 16 hybrids and 2 groups of genitors. In the diallel analysis of variance, we observed a significant difference among treatments. A significant difference was observed among genitors for dry matter production (DMP). For the general combining ability of group 1, the traits leaf blade width, DMP, height, percentage of neutral detergent fiber, percentage of hemicellulose, percentage of lignin, percentage of acid detergent fiber, and percentage of cellulose were significant. For the estimates of general combining ability of DMP, parents Porto Rico 534-B, Vruckwona, Taiwan A-146, and Mercker S. E. A. were 0.4748, 3.2819, 1.1659, and 0.4317. The parents of Mercker S. E. A. and Porto Rico 534-B produced the highest percentage of detergent fiber and percentage of lignin with values of 0.1482 and 0.0856. Thus, parents Vruckwona, Porto Rico 534-B, and Taiwan A-146 are promising for integration into breeding programs. The best hybrid combinations for DMP were 1 x 5, 1 x 8, 2 x 6, 3 x 7, and 4 x 5.

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In addition to phenolics, flavonoids, flavonols, alkaloids and condensed tannins, our tests identified the antioxidant and genotoxic properties in the crude extract (CE) and fractions of Urera baccifera (Urticaceae) roots and leaves. Oxalic acid (OA) content was determined by HPLC-DAD, which presented high values in the roots (1.82 ± 0.21, 1.79 ± 0.22 and 1.38 ± 0.15 mg/g in butanolic, CE and ethyl acetate fraction, respectively). OA caused a 30.7% reduction in the leucocyte proliferation, followed by butanolic fractions of roots (24.15%) and leaves (23.28%). The mitotic index was lower in butanolic fractions of leaves (8.7%) and roots (8.3%), similar to the OA index, which was 6.0%. The DNA damage index in cultured leukocytes was observed for OA (19.33) and butanol fraction treatments (22.67 and 16, respectively, for leaves and roots). Antioxidant capacity (DPPH and TBARS) was moderated, which was confirmed by the low phenolic, flavonol and flavonoid contents in both parts of the plant.

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Parapiptadenia rigida, locally known as angico, is a tropical tree common in the semideciduous Brazilian forest. Its wood is naturally resistant to insect attack and is useful for construction. Extracts from the tree have medicinal properties. We characterized nine microsatellite loci for P. rigida. Thirty-five alleles were detected in a sample of 45 individuals from 3 different populations, with an average of 3.9 alleles per locus. The average polymorphic information content ranged from 0.099 to 0.640. Observed and expected heterozygosities varied from 0.111 to 0.489 and from 0.106 to 0.707, respectively. One locus exhibited significant deviation from Hardy-Weinberg equilibrium and four pairs of loci showed significant linkage disequilibrium. All nine primers were tested for cross-amplification in species from the Fabaceae-Mimosoidea family, yielding a transferability success rate of 7 loci in Stryphnodendron adstringens to 0 transferred loci in Pithecellobium incuriale and Inga marginata. These microsatellites will be valuable to study population genetics of this and other species where primer transferability was detected.

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In the Stroop matching task, a Stroop word is compared to a colored bar. The origin of the conflict presented by this task is a topic of current debate. In an effort to disentangle nonresponse and response conflicts, we recorded electromyography (EMG) and event-related potentials (ERPs) while participants performed the task. The N450 component was sensitive to the relationship of color surfaces, regardless of the response, suggesting the participation of nonresponse conflict. Incompatible arrays (e.g., incongruent Stroop stimuli during "same" responses) presented a substantial amount of double EMG activation and slower EMG latencies, suggesting the participation of response conflict. We propose that both response and nonresponse conflicts are sources of these effects. The combined use of the EMG and ERP techniques played an important role in elucidating the conflicts immersed in the Stroop matching task.

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A variety of injectable permanent fillers have been used in orofacial tissues for cosmetic purposes. Most of these substances seem to be well tolerated but adverse reactions have been reported. Foreign body granulomas are a rare adverse reaction to injectable permanent fillers. The authors report the unusual case of a 56-year-old woman with a foreign body granuloma located exclusively in the oral cavity that was due to injection of a permanent filler.

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Empregou-se a estimulação elétrica neuromuscular (EENM) de baixa freqüência no músculo quadríceps femoral de cães com atrofia induzida e avaliou-se a ocorrência de ganho de massa nessa musculatura. Foram utilizados oito cães com pesos entre 15 e 30kg, distribuídos aleatoriamente em dois grupos denominados de I ou controle e II ou tratado. A articulação femorotibiopatelar esquerda foi imobilizada por 30 dias pelo método de transfixação percutânea tipo II, com retirada de aparelho de imobilização após esse período. Decorridas 48 horas da remoção, foi realizada a EENM nos cães do grupo II, cinco vezes por semana, com intervalo de 24 horas cada sessão, pelo período de 60 dias. Foram avaliadas a circunferência da coxa, a goniometria do joelho, a análise clínica da marcha, as enzimas creatina-quinase (CK) e aspartato-amino-transferase (AST) e a morfometria das fibras musculares em cortes transversais do músculo vasto lateral colhido mediante biópsia muscular. A EENM foi empregada no músculo quadríceps femoral na freqüência de 50Hz, duração de pulso de 300 milisegundos e relação de tempo on/off de 1:2. Quanto à morfometria das fibras do músculo vasto lateral, no grupo tratado houve aumento significativo (P<0,05) da área transversal aos 90 dias em relação ao dia zero. A EENM de baixa freqüência ocasiona hipertrofia do músculo vasto lateral em cães após a imobilização rígida temporária da articulação do joelho.

Low frequency neuromuscular electrical stimulation (NMES) was used on the femoral quadriceps of dogs with induced muscular atrophy and the occurrence of gain in mass in these muscles was evaluated. Eight dogs from 15 to 30kg were randomly distributed in two groups named I, or control; and II, or treated. For the induction of muscular atrophy, the left femoral-tibial-patellar joint was immobilized for 30 days by percutaneous transfixation type II. After 30 days, the immobilization device was removed. The NMES treatment began 48 hours after the removal of the immobilization device of the dogs of group II, and it was carried out five times per week with an interval of 24 hours between each session, for 60 days. The following parameters were measured: thigh circumference, goniometry of the knee, clinical gait analysis, creatine kinase (CK) and aspartate aminotransferase (AST) enzymes, and morphometry of the muscular fibers in transversal cuts of the vastus lateralis muscle collected through muscular biopsy. The NMES was applied on the femoral quadriceps at a frequency of 50 Hz, with pulse duration of 300 milliseconds, and the on/off time was at a proportion of 1:2. Regarding the morphometry of the vastus lateralis fibers, a significant increase (P<0.05) in the transversal area of the treated group at 90 days was observed when compared with that identified at the time of immobilization. Thus, it can be concluded that low frequency NMES brings about hypertrophy of the vastus lateralis muscle in dogs after temporary rigid immobilization of the knee joint.

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OBJECTIVE: Investigate the immunohistochemical distribution of fibronectin, tenascin, laminin and collagen IV in syndrome (SOKC) and non-syndrome odontogenic keratocysts (NSOKC). MATERIALS AND METHODS: Ten cases of SOKC and five of NSOKC were selected and streptoavidin-biotin technique was applied. The specimens were analyzed taking into account the following evaluation parameters: presence, continuity and thickness in the basement membrane and intensity, distribution and association with inflammatory cells in the cyst wall. RESULTS: Differences could be detected regarding tenascin, fibronectin and collagen IV between the SOKC and NSOKC. Tenascin was present in all cases along the basement membrane in SOKC and in five cases of NSOKC predominated negative areas. Furthermore, tenascin distribution was focal in the cyst wall in SOKC whereas in NSOKC it was diffuse. Concerning fibronectin, it was detected as a discontinuous band when present in SOCK and as a continuous band in NSOKC. Collagen IV was not present in the majority of the cases in SOKC. Negative areas for laminin predominated in the basement membrane in both groups. CONCLUSIONS: These findings show differences between the immunohistochemical expression of tenascin, fibronectin and collagen IV which might indicate a more aggressive biological behavior of SOKC as compared with NSOKC.

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La habilidad de conciencia fonémica se relaciona con el acto de segmentar los fonemas del habla y manipular tales segmentos. En el presente estudio se aplicaron las tareas de habilidades fonémicas a niños alfabetizados y no alfabetizados, efectuándose un estudio comparativo de los resultados obtenidos. Este estudio estuvo formado por 15 niños alfabetizados y 15 niños no alfabetizados, ambos grupos pertenecían al mismo rango de edad. Los resultados demostraron que los escolares alfabetizados presentaban mayor desempeño en las tareas de habilidades fonémicas (tales como sustracción de fonemas y sustitución de fonemas) que los escolares no alfabetizados, revelando que el aprendizaje de la lectura y escritura mejora el conocimiento de estas habilidades. Este hecho orienta para la conclusión de que existe un continuum en la graduación de estas capacidades (AU)

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