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Breast cancer (BC) with average human epidermal growth factor receptor 2 (HER2) signals/cell ≥6 and HER2/chromosome enumeration probe 17 (CEP17) ratio <2 (in situ hybridization [ISH] group 3) is very rare, accounting for 0.4% to 3.0% of cases sent for the dual-probe ISH assay. Although such patients are currently eligible for treatment with HER2-targeted therapy, their characteristics and outcomes remain poorly understood. Sixty-two BCs with equivocal HER2 immunohistochemical score (2+) and reflex ISH group 3 results were identified across 4 institutions. Available clinicopathologic characteristics, MammaPrint and BluePrint molecular results, and follow-up information were retrospectively analyzed. Most BCs with HER2 equivocal immunohistochemical and ISH group 3 results were histologic grade 2 or 3 (100%), estrogen receptor (ER) positive (90.3%), with an average HER2 signals/cell of 7.3. Molecular profiles revealed that 80% (16/20) of tumors were luminal subtypes, and HER2 molecular subtype was identified in 10% of tumors (2/20). Twelve (19.4%) out of 62 patients developed local recurrence and/or distant metastasis with a median follow-up of 50 months. One (10%) of 10 patients achieved pathologic complete response after neoadjuvant chemotherapy. Forty-nine (79%) out of 62 patients completed anti-HER2 agents, and exploratory analysis showed no statistically significant difference in disease outcomes between patients who completed anti-HER2 treatment and those who did not. Univariate analysis revealed advanced clinical stage, and ER/progesterone receptor negativity was associated with unfavorable disease outcomes, and exploratory multivariate analysis demonstrated that clinical stage was the most significant factor associated with disease outcomes in the studied population. These findings increase our understanding of this rare, but clinically important HER2 category. Large-scale prospective randomized studies are needed to further evaluate the role of perioperative HER2-targeted therapy in this patient population.
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Freshwater bivalves play key ecological roles in lakes and rivers, largely contributing to healthy ecosystems. The freshwater pearl mussel, Margaritifera margaritifera, is found in Europe and on the East coast of North America. Once common in oxygenated streams, M. margaritifera is rapidly declining and consequently assessed as a threatened species worldwide. Deterioration of water quality has been considered the main factor for the mass mortality events affecting this species. Yet, the role of parasitic infections has not been investigated. Here, we report the discovery of three novel protist lineages found in Swedish populations of M. margaritifera belonging to one of the terrestrial groups of gregarines (Eugregarinorida, Apicomplexa). These lineages are closely related-but clearly separated-from the tadpole parasite Nematopsis temporariae. In one lineage, which is specifically associated with mortality events of M. margaritifera, we found cysts containing single vermiform zoites in the gills and other organs of diseased individuals using microscopy and in situ hybridization. This represents the first report of a parasitic infection in M. margaritifera that may be linked to the decline of this mussel species. We propose a tentative life cycle with the distribution of different developmental stages and potential exit from the host into the environment.
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Bivalvos , Agua Dulce , Filogenia , Animales , Suecia , Agua Dulce/parasitología , Bivalvos/parasitología , Apicomplexa/clasificación , Apicomplexa/aislamiento & purificación , Apicomplexa/genética , Apicomplexa/fisiología , Branquias/parasitologíaRESUMEN
Innate immunity is vital for animal homeostasis and survival. First-line immuno-defense for fish larvae involves mucus enriched with leukolectin (LL) secreted by dermal lectocytes. Later during the critical transition from yolk-nutrition to feeding, additional larval immuno-protection in zebrafish (zF) is provided by macrophages containing LL (lectophages). This work investigated new LL-expression in embryos and in blood, structures of fish leukocytic LL and LL-genes, and LL-presence in chicken leukocytes. In zF-embryos, lectophages appear â¼10 hpf, while later, cells co-expressing myeloperoxidase- and LL-mRNA were detected (â¼19 hpf). Furthermore, protein-extracts of Atlantic salmon (Ssal) leukocytes contained LL-proteins, compartmentalized in the cytosol. Cloning and sequencing revealed 94 % nt-sequence identity between variants of Ssal-leukolectins. Highly conserved LLs allowed production of epitope-specific anti-LL IgGs. Immuno-fluorescence-analysis demonstrated that most Ssal-bloodcells were LL-negative, but both some large cells with protrusions and some small, rounded cells did express LL. Immunoperoxidase-staining method confirmed LL-expression in some Ssal-leukocytes, identified as macrophages, PMN-leukocytes, thrombocytes and dendritic cells. However, closer examination revealed a dichotomy of these cell-categories into either LL-positive, or LL-negative variants. In situ hybridization demonstrated profuse LL-expression in Ssal head kidney interstitial tissue, while LL-transcripts were absent in large kidney tubules. Both hematopoietic (non-pigmented) marrow cells and melano-macrophages expressed LL-mRNA, implying that leukolectins provide lifelong innate immuno-protection. PCR-amplification using Ssal-leukocytic DNA as template, and direct sequencing yielded a leukocytic ll-gene. Some cells in salmon, cod, halibut, oikopleura and zebrafish embryos express LL-proteins and/or LL-mRNA, and LL-mRNA is detected in salmon, cod and chicken leukocytes. However, current genomes for these species lack recognizable LL-loci except the Ssal_v3.1 Genome-assembly. The data demonstrate an unexpected dichotomy of some leukocyte lineages into LL-positive or LL-negative cell-variants. Such dichotomies suggest exploring differential impacts from the duplicated leukocyte-lineages in health and disease.
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Inmunidad Innata , Leucocitos , Salmo salar , Pez Cebra , Animales , Inmunidad Innata/genética , Pez Cebra/inmunología , Pez Cebra/genética , Leucocitos/inmunología , Salmo salar/inmunología , Salmo salar/genética , Pollos/inmunología , Pollos/genética , Proteínas de Peces/genética , Proteínas de Peces/inmunologíaRESUMEN
The cell surface metalloprotease ADAM17 (a disintegrin and metalloprotease 17) and its binding partners iRhom2 and iRhom1 (inactive Rhomboid-like proteins 1 and 2) modulate cell-cell interactions by mediating the release of membrane proteins such as TNFα (Tumor necrosis factor α) and EGFR (Epidermal growth factor receptor) ligands from the cell surface. Most cell types express both iRhoms, though myeloid cells exclusively express iRhom2, and iRhom1 is the main iRhom in the mouse brain. Here, we report that iRhom2 is uniquely expressed in olfactory sensory neurons (OSNs), highly specialized cells expressing one olfactory receptor (OR) from a repertoire of more than a thousand OR genes in mice. iRhom2-/- mice had no evident morphological defects in the olfactory epithelium (OE), yet RNAseq analysis revealed differential expression of a small subset of ORs. Notably, while the majority of ORs remain unaffected in iRhom2-/- OE, OSNs expressing ORs that are enriched in iRhom2-/- OE showed fewer gene expression changes upon odor environmental changes than the majority of OSNs. Moreover, we discovered an inverse correlation between the expression of iRhom2 compared to OSN activity genes and that odor exposure negatively regulates iRhom2 expression. Given that ORs are specialized G-protein coupled receptors (GPCRs) and many GPCRs activate iRhom2/ADAM17, we investigated if ORs could activate iRhom2/ADAM17. Activation of an olfactory receptor that is ectopically expressed in keratinocytes (OR2AT4) by its agonist Sandalore leads to ERK1/2 phosphorylation, likely via an iRhom2/ADAM17-dependent pathway. Taken together, these findings point to a mechanism by which odor stimulation of OSNs activates iRhom2/ADAM17 catalytic activity, resulting in downstream transcriptional changes to the OR repertoire and activity genes, and driving a negative feedback loop to downregulate iRhom2 expression.
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Neuronas Receptoras Olfatorias , Receptores Odorantes , Animales , Receptores Odorantes/metabolismo , Receptores Odorantes/genética , Ratones , Neuronas Receptoras Olfatorias/metabolismo , Olfato/fisiología , Proteína ADAM17/metabolismo , Proteína ADAM17/genética , Ratones Noqueados , Proteínas Portadoras/metabolismo , Proteínas Portadoras/genética , Mucosa Olfatoria/metabolismo , Regulación de la Expresión Génica , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Ratones Endogámicos C57BL , HumanosRESUMEN
Bordetella holmesii is a bacterium recently recognized in 1995. It is a gram-negative coccobacillus that can cause pertussis-like symptoms in humans as well as invasive infections. It is often confused with Bordetella pertussis because routine diagnostic tests for whooping cough are not species-specific. The prevalence of B. holmesii as a cause of pertussis has increased in several countries. Therefore, B. holmesii assays are important for determining the epidemiology of pertussis, for the choice of an effective treatment, and for detecting vaccination failures.
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Bordetella , Tos Ferina , Humanos , Tos Ferina/diagnóstico , Tos Ferina/epidemiología , Tos Ferina/prevención & control , Bordetella pertussisRESUMEN
Background: Breast cancer (BC) is the most prevalent cancer among women worldwide. Although advances have been made in the identification of predictive biomarkers, current options for early diagnosis and prognostic analysis are still suboptimal. Recently, transfer-RNA-derived RNA fragments (tRFs) have emerged as a class of small noncoding RNAs that play a role in the cancer progression. The authors aimed to identify a specific class of tRFs as a molecular marker for BC diagnosis and prognosis in clinical management. Methods: The levels of 5'-tRF-His-GTG were quantified in BC tissue (n = 101) and inflammatory normal breast tissue (n = 22) using in situ hybridization. Clinicopathological parameters were obtained, including age, tumor node metastasis stage, hormone receptor status, histopathological grade, lymphovascular invasion, and recurrence. The correlation between the expression of 5'-tRF-His-GTG and these parameters in different BC subtypes was analyzed. Patient death and cancer progression were regarded as clinical endpoints in the survival analysis. Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were also performed to predict the involvement in pivotal biological process. Results: The expression of 5'-tRF-His-GTG was significantly downregulated in BC tissues and was in connection with T stage in human epidermal growth factor 2-positive and basal-like BC, as well as N stage and histopathological grade in luminal BC. Patients with low expression of 5'-tRF-His-GTG had a poor overall survival rate. Statistics of GO and KEGG pathway revealed that cation channel activity, protein catabolic process, response to temperature stimulus, cell cycle, focal adhesion, and glycerophospholipid metabolism were significantly enriched. Conclusions: This study suggests that the assessment of 5'-tRF-His-GTG expression could serve as a novel biomarker for individual diagnosis and prognosis in BC.
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Biomarcadores de Tumor , Neoplasias de la Mama , Humanos , Neoplasias de la Mama/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/diagnóstico , Femenino , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Pronóstico , Persona de Mediana Edad , Adulto , AncianoRESUMEN
High-risk human papillomavirus (hrHPV) is an emerging risk factor for sinonasal squamous cell carcinoma (SNSCC). The goal of this study was to assess the prevalence of hrHPV and subtype distribution in SNSCC and correlation with patient and clinical characteristics. This retrospective cohort study included 43 cases diagnosed with incident primary SNSCC at the University of Cincinnati Medical Center from 2010 to 2015. The prevalence of hrHPV was interrogated using a multi-assay approach that included p16 immunohistochemistry (IHC), RNA in-situ hybridization (ISH), and hrHPV DNA sequencing. The association of hrHPV with 5-year overall survival (OS) and 2-year disease-free survival (DFS) was assessed. Fourteen cases (32.6â¯%) were classified as hrHPV positive, based on the a priori definition of having either a positive RNAScope™ ISH test or hrHPV DNA and p16-positive IHC; 9 cases (20.9â¯%) were positive for all three tests. All cases that arose from an inverted sinonasal papilloma (ex-ISP) were negative for hrHPV. HPV16 was the most common subtype among hrHPV positive cases (58.8â¯%), followed by HPV18 (17.6â¯%). No significant association was observed between hrHPV and OS or DFS after adjusting for potential confounding. hrHPV is prevalent in a sizable fraction of SNSCC. Additional studies are needed to better elucidate the relationship with patient survival outcomes and determine the optimal testing modality for prognostication.
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Virus del Papiloma Humano , Infecciones por Papillomavirus , Neoplasias de los Senos Paranasales , Carcinoma de Células Escamosas de Cabeza y Cuello , Humanos , Virus del Papiloma Humano/genética , Virus del Papiloma Humano/aislamiento & purificación , Inmunohistoquímica , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/mortalidad , Infecciones por Papillomavirus/patología , Infecciones por Papillomavirus/virología , Neoplasias de los Senos Paranasales/mortalidad , Neoplasias de los Senos Paranasales/patología , Neoplasias de los Senos Paranasales/virología , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello/virología , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidadRESUMEN
The article discusses the importance of accurately distinguishing HER2-low from HER2-negative breast cancer, as novel ADCs have demonstrated activity in a large population of patients with HER2-low-expressing BC. While current guidelines recommend a dichotomous classification of HER2 as either positive or negative, the emergence of the HER2-low concept calls for standardization of HER2 testing in breast cancer, using currently available assays to better discriminate HER2 levels. This review covers the evolution and latest updates of the ASCO/CAP guidelines relevant to this important biomarker in breast cancer, including still-evolving concepts such as HER2 low, HER2 heterogeneity, and HER2 evolution. Our group presents the latest Mexican recommendations for HER2 status evaluation in breast cancer, considering the ASCO/CAP guidelines and introducing the HER2-low concept. In the era of personalized medicine, accurate HER2 status assessment remains one of the most important biomarkers in breast cancer, and the commitment of Mexican pathologists to theragnostic biomarker quality is crucial for providing the most efficient care in oncology.
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Transient Receptor Potential Ankyrin 1 (TRPA1) is a non-selective cation channel involved in sensitivity to a plethora of irritating agents and endogenous mediators of oxidative stress. TRPA1 influences neuroinflammation and macrophage and lymphocyte functions, but its role is controversial in immune cells. We reported earlier a detectable, but orders-of-magnitude-lower level of Trpa1 mRNA in monocytes and lymphocytes than in sensory neurons by qRT-PCR analyses of cells from lymphoid organs of mice. Our present goals were to (a) further elucidate the expression of Trpa1 mRNA in immune cells by RNAscope in situ hybridization (ISH) and (b) test the role of TRPA1 in lymphocyte activation. RNAscope ISH confirmed that Trpa1 transcripts were detectable in CD14+ and CD4+ cells from the peritoneal cavity of mice. A selective TRPA1 agonist JT010 elevated Ca2+ levels in these cells only at high concentrations. However, a concentration-dependent inhibitory effect of JT010 was observed on T-cell receptor (TcR)-induced Ca2+ signals in CD4+ T lymphocytes, while JT010 neither modified B cell activation nor ionomycin-stimulated Ca2+ level. Based on our present and past findings, TRPA1 activation negatively modulates T lymphocyte activation, but it does not appear to be a key regulator of TcR-stimulated calcium signaling.
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Activación de Linfocitos , Canal Catiónico TRPA1 , Canal Catiónico TRPA1/metabolismo , Canal Catiónico TRPA1/genética , Animales , Ratones , Activación de Linfocitos/efectos de los fármacos , Linfocitos T/metabolismo , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Ligandos , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/efectos de los fármacos , Acetanilidas/farmacología , Ratones Endogámicos C57BL , Calcio/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , ARN Mensajero/metabolismo , ARN Mensajero/genética , Masculino , Señalización del Calcio/efectos de los fármacosRESUMEN
The gene localization technique of Bursaphelenchus xylophilus (pinewood nematode, PWN) is used for study gene expression in PWNs. Two in situ hybridization methods, namely, whole-mount in situ hybridization and the cut-off method are used widely. To compare the effects of these two in situ hybridization methods, the present study investigated the patterns of two functional genes expression in PWNs. The Bx-vap-2 gene (GenBank accession number: OR228482), related to pathogenicity, and the fem-2 gene (GenBank accession number: OR228481), related to sex determination, were selected to map related genes in the whole-mount and amputated PWNs at different ages using these in situ hybridization methods. Based on the overall statistical comparison, we found that compared to the cut-off method, the whole-mount method exhibited higher staining rates and correct staining rates for the fem-2 gene and Bx-vap-2 gene. However, considering the correct staining aspect, the cut-off method yielded better staining effects on pinewood nematode sections than the whole-mount method, with clearer hybridization signal locations and less non-specific staining. In other words, the cut-off method demonstrated more precise gene localization. Both methods are applicable for gene localization, but considering the overall staining pattern, analysis of experimental results, and comprehensive experimental operations, we believe that the whole-mount method is more suitable for gene localization and expression analysis of development-related genes in pinewood nematodes. This is because intact pinewood nematodes are better suited for showcasing the continuous developmental process of development-related genes. On the other hand, considering the experimental time, accuracy of staining site, and the amount of non-specific staining, the cut-off method is more suitable for disease-related genes. Additionally, to achieve better performance, the cut-off method can be selectively applied to samples during the experimental process.
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Lymphoepithelioma-like carcinoma of the skin (LELCS) is a rare primary skin cancer, with an annual incidence of 1/100,000 and about 85 cases published in the literature. It is considered the cutaneous counterpart of undifferentiated nasopharyngeal carcinoma (UNC, Schmincke-Regaud tumor) but has no association with EBV. We present an interesting case with features of LELCS in a 93-year-old man, right frontal-orbital region, diagnosed histologically and with immunohistochemical features. We also emphasize contrasting morphologic features for correct nosographic classification and address current issues, suggesting potential insights. Finally, we briefly reviewed other cases described in the literature.
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Introducción. Un subgrupo de los carcinomas de mama sobreexpresa el receptor 2 del factor de crecimiento epidérmico (HER2). La determinación de esta sobreexpresión se realiza por inmunohistoquímica. La dificultad de diagnóstico surge cuando el resultado es ambiguo (2+), haciendo necesario realizar hibridación in situ (ISH) para determinar la amplificación del gen HER2/neu. Objetivo. Determinar si la amplificación del gen HER2/neu en los casos HER2 2+, se encuentra asociado a factores clinicopatologicos pronósticos. Diseño. Estudio descriptivo de corte transversal. Institución. Servicio de patología quirúrgica, Hospital Guillermo Almenara Irigoyen. Lima, Perú. Participantes. Casos de cáncer de mama HER2 2+. Metodología. Se estudiaron 117 casos de cáncer de mama HER2 2+ diagnosticados entre los años 2010 2015, a los que posteriormente se les realizó ISH. Todos los datos fueron analizados con el programa estadístico SPSS 22. Se utilizó el test de Chi cuadrado para analizar la asociación entre las variables. Principales medidas de resultados. Factores asociados a la amplificación del gen HER2/neu. Resultados. La amplificación del gen HER2/neu se observó en 41% del total de casos. En estos, se observó con mayor frecuencia un grado histológico III (66%), compromiso ganglionar presente (61%), tamaño tumoral ≥ 2 cm (86%) y Ki 67 ≥ 20% (83%). Se encontró una asociación estadísticamente significativa con una edad ≥ 50 años (X2 test, P=0,004) y el grado histológico III (X2 test, P=0.017). Conclusión. La amplificación del gen HER2/neu en casos ambiguos está asociado a una edad ≥ 50 años y grado histológico III.
Introduction: A subgroup of breast carcinomas overexpress epidermal growth factor-2 (HER2). The determination of this overexpression is carried out by immunohistochemistry. The difficulty of diagnosis by this method arises when the result is ambiguous (2+), thus it is necessary to perform in situ hybridization (ISH) to determine the amplification of the HER2/neu gene. Objective: To determine if, in HER2 2+ cases, the amplification of the HER 2 / neu gene is associated with prognostic clinicopathological factors. Design: Observational, cross-sectional, descriptive study. Institution: Surgical pathology service, Guillermo Almenara Irigoyen Hospital. Lima, Peru. Participants: Cases of breast cancer HER2 2+. Methodology: We studied 117 cases of Her2 2+ breast cancer diagnosed between the years 2010 2015, to which ISH was subsequently performed. All the data were analyzed with the statistical program SPSS 22. The Chi-square test was used to analyze the association between the variables. Main results measures: Factors associated with the amplification of the HER2 / neu gene. Results: Amplification of the HER2 / neu gene was observed in 41% of the total cases. In these, a histological grade III (66%), lymph node involvement (61%), tumor size ≥ 2 cm (86%) and Ki 67 ≥ 20% (83%) were observed more frequently. A statistically significant association was found with an age ≥ 50 years (X2 test, P = 0,004) and histological grade III (X2 test, P = 0.017). Conclusion: Amplification of the HER2/ neu gene in ambiguous cases is associated with an age ≥50 years and histological grade III
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Epstein-Barr virus (EBV) has been associated with 10% of gastric carcinomas. The aim of this study was to determine the frequency of EBV in gastric carcinomas in Brazil assessed by in situ hybridization (ISH) and PCR, which would contribute to the characterization of the clinical and pathological aspects of EBV-associated gastric carcinomas. One hundred and ninety-two gastric carcinoma cases were collected at hospitals in two Brazilian states. Seventy-three out of 151 cases were PCR(+), while 11/160 cases were ISH(+). Nine out of eleven ISH(+) cases displayed a diffuse staining pattern and 2 out of 11 a focal pattern. Both techniques showed that the EBV(+) cases were characterized by their association with males, older patients, lower gastric region, intestinal type, advanced stage and poorly to moderately differentiated tumors. The concordance between the two techniques was 55.8% (Cohen's kappa index = 0.034). Four cases were ISH(+)/PCR(-), while 49 cases were PCR(+)/ISH(-). Only two cases showed stained lymphocytes by ISH and one of them was PCR(-). The observed discrepancy between the two techniques could not be explained just by the elevated accuracy of PCR. ISH(+)/PCR(-) carcinomas may be encountered if EBV is not present in the whole tumor tissue or if there are polymorphisms in the sequences of the viral genome amplified. On the other hand, the high frequency of PCR(+) results associated with the absence of ISH staining in lymphocytes and/or tumors cells suggests that the virus may be present in tumor cells or other cell types without expressing EBER1, the target of the ISH technique.
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Humanos , Masculino , Carcinoma , Infecciones por Virus de Epstein-Barr , Tracto Gastrointestinal , /genética , /aislamiento & purificación , Hibridación in Situ/métodos , Técnicas In Vitro , Reacción en Cadena de la Polimerasa/métodos , Células Tumorales Cultivadas , Métodos , Pacientes Ambulatorios , MétodosRESUMEN
No presente trabalho realizou-se um estudo do processo de refino de óleo de pescado, determinando-se através de um Planejamento Experimental Fatorial as variáveis que influenciam significativamente as etapas de neutralizaçäo e branqueamento. O óleo bruto de pescado foi tratado com ácido fosfórico 85(por cento), neutralizado com hidróxido de sódio 20(por cento)p/p em excesso, lavado com água quente e seco sob o vácuo, sendo branqueado com substâncias adsorventes, e filtrado. Na etapa de neutralizaçäo obteve-se um óleo com Índice de Perióxidos de 2,1 mEq/Kg e 0,04(por cento) de Ácidos Graxos Livres, na faixa de 40oC e 40(por cento) de excesso de NaOH 20(por cento), sendo a temperatura e o excesso de NaOH, as variáveis de principal influência no processo. No estudo da etapa de branqueamento foi utilizado um planejamento experimental fatorial completo (2k), tendo como parâmetros a temperatura, o tempo de retençäo, a (por cento) Adsorvente e a (por cento) Carväo/Adsorvente, sendo que estes últimos influenciaram significativamente na cor lovibond e no Índice de Perióxidos de óleo clarificado. Os Melhores resultados para a cor Lovibond (30 Amarelo e 1,24 Vermelho) e para o Índice de Perióxido (3,93 mEq/Kg) do óleo clarificado foram encontrados nas faixas de 70oC e tempo de 20 minutos, com 5,0(por cento) de Adsorvente e 10(por cento) de (Carväo/Adsorvente). (AU)
In the current work a process of refining fish oil was studied that determined, through Factorial Experimental Design, the variables which significantly influence the neutralization and bleaching stages. The crude fish oil was treated with phosphoric acid 85%, neutralized with sodium hidroxide 20% w/w in excess, washed with hot water and dried under vacuum, being bleached with adsorbent substances and filtered. During the neutralization stage some oil with Peroxide Values of 2.1 mEq/Kg and 0.04 of Free Fatty Acids was obtained, in the range of 40∞C and 4.0% excess NaOH 20%. The temperature and the excesso NaOH were the main influential variables of the process. During the bleaching stage, a complete factorial experimental design (2 K) involving temperature, retention time, %Adsorbent and %Charcoal/Adsorbent was used. The % Adsorbent and% Charcoal/Adsorbent significantly influenced the Lovibond color and Peroxide Values of the bleached oil. The best results for the Lovibond Red 1.24, Lovibond Yellow 30 and Peroxide Value of 3.93 meq/Kg of the bleached oil were found in the range of 70∞C and time of 20 minutes, with 5.0% of adsorbent and 10.0% of Charcoal/Adsorbent. (AU)