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1.
Medicina (Kaunas) ; 60(10)2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39459375

RESUMEN

Class III malocclusion prevalence varies significantly among racial groups, with the highest prevalence observed in southeast Asian populations at 15.80%. These malocclusions often involve maxillary retrognathism, mandibular prognathism, or both, accompanied by maxillary constriction and crossbites. Comprehensive treatment should address anteroposterior, transverse, and vertical imbalances. Microimplant-assisted rapid palatal expansion (MARPE) has shown high success rates for transverse maxillary expansion in late adolescents and adults, presenting a viable alternative to surgically-assisted rapid palatal expansion (SARPE). This case report aims to demonstrate the successful treatment of a young adult female with borderline Class III malocclusion using MARPE and mandibular backward rotation (MBR) techniques. A 21-year-old female presented with a Class III skeletal pattern, anterior/posterior crossbites, and mild dental crowding. Despite her concerns about a concave facial profile, the patient declined orthognathic surgery due to a negative experience reported by a friend. The treatment plan included MARPE to correct maxillary transverse deficiency and MBR to alleviate Class III malocclusion severity. Lower arch distalization was performed using temporary anchorage devices (TADs) on the buccal shelves, and Class II elastics were used to maintain MBR and prevent retroclination of the lower labial segment during anterior retraction. Significant transverse correction was achieved, and the severity of Class III malocclusion was reduced. The lower dentition was effectively retracted, and the application of Class II elastics helped maintain MBR. The patient's final facial profile was harmonious, with well-aligned dentition and a stable occlusal relationship. The treatment results were well-maintained after one year. The MARPE with MBR approach presents a promising alternative for treating borderline Class III cases, particularly for patients reluctant to undergo orthognathic surgery. This case report highlights the effectiveness of combining MARPE and MBR techniques in achieving stable and satisfactory outcomes in the treatment of Class III malocclusion.


Asunto(s)
Maloclusión de Angle Clase III , Mandíbula , Técnica de Expansión Palatina , Humanos , Femenino , Técnica de Expansión Palatina/instrumentación , Maloclusión de Angle Clase III/cirugía , Maloclusión de Angle Clase III/terapia , Adulto Joven , Mandíbula/cirugía , Mandíbula/anomalías , Resultado del Tratamiento , Adulto
2.
Chemosphere ; 318: 137932, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36690258

RESUMEN

From an environmental perspective, approaching sustainability requires a fundamental conceptual shift from the wastewater treatment process toward integrated treatment systems that consider efficient and effective utilization. This study aims to investigate the effects of different surfactants on the removal of perfluorooctanoic acid (PFOA). We used cationic surfactants as both frothers and collectors in the electrocoagulation-flotation (ECF) method to improve the removal efficiency of PFOA. The results showed that, under a monopolar aluminum electrode and with an initial PFOA concentration of 0.25 mM, the ECF method with decyl-trimethyl-ammonium bromide (DTAB) was able to remove over 98% of PFOA within 10 min. Cationic surfactants with a similar linear alkyl chain shape to PFOA, but a longer chain length, are more effective at removing PFOA through the ECF process. The removal mechanism is thought to involve co-precipitation with aluminum hydroxides through Al-F bonding, co-flotation with cationic surfactants, and mixed micelle formation with cationic surfactants. The optimal conditions were tested in both synthetic and realistic wastewater matrices and produced similar results. It has the potential for real wastewater application. The energy yield (G50) of ECF with 5 mM DTAB is 497 g·kWh-1, superior to other treatments, and is an extremely energy-effective method for separating PFOA from wastewater.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Aluminio , Conservación de los Recursos Energéticos , Tensoactivos , Electrocoagulación/métodos
3.
Arch Pathol Lab Med ; 147(3): 348-358, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35738007

RESUMEN

CONTEXT.­: Bone marrow (BM) samples are obtained through aspiration and trephine biopsy. Hemophagocytic lymphohistiocytosis (HLH) has been largely studied in BM aspirate smears. OBJECTIVE.­: To investigate the histologic features of HLH in trephine biopsy. DESIGN.­: Patients with hemophagocytosis in BM aspirate smears were assigned to HLH (n = 127) and non-HLH (n = 203) groups. We quantified hematoxylin-eosin and CD68 immunohistochemical staining of their trephine biopsies. RESULTS.­: No significant correlation was noted in the hemophagocytosis count between aspirate smears and trephine biopsies. Compared with the non-HLH group, the HLH group had a higher hemophagocytosis count (13 versus 9 per tissue section, P = .046), lower percentage of the adipocytic area (36.7% versus 50.3%, P < .001), and higher percentage of the foamy area (19.1% versus 14.5%, P < .001). The HLH group had more histiocyte infiltrates (total histiocyte density, 9.2% versus 7.3%; P < .001) and more fat-infiltrating histiocytes (histiocyte density of the fat-associated part [HD-FA], 7.6% versus 6.2%; P < .001). We identified the following poor prognostic factors in the HLH group: age 50 years or older (median overall survival [mOS], 95 versus 499 days; P = .04), Epstein-Barr virus-positive T-cell lymphoproliferative diseases (EBV+TLPDs) (mOS, 51 versus 425 days; P < .001), hemophagocytosis count of 6 or higher per tissue section (mOS, 66 versus 435 days; P = .02), and HD-FA of 9% or greater (mOS, 61 versus 359 days; P = .02). Multivariate analysis revealed that age 50 years or older (hazard ratio [HR], 2.38; P < .001), EBV+TLPDs (HR, 2.07; P < .001), and hemophagocytosis count of 6 or higher per tissue section (HR, 2.07; P = .002) were independent prognostic factors for HLH. CONCLUSIONS.­: The HLH group had higher hemophagocytic activity, higher cellularity, a more foamy appearance, more histiocyte infiltrates, and more fat-infiltrating histiocytes. High hemophagocytic activity and marked histiocyte infiltrates in the BM fat were associated with poorer prognosis.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Linfohistiocitosis Hemofagocítica , Humanos , Persona de Mediana Edad , Linfohistiocitosis Hemofagocítica/diagnóstico , Linfohistiocitosis Hemofagocítica/patología , Infecciones por Virus de Epstein-Barr/patología , Médula Ósea/patología , Herpesvirus Humano 4 , Biopsia
4.
J Hematop ; 16(2): 103-109, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38175441

RESUMEN

Adult B-lineage acute lymphoblastic leukemia (B-ALL) with t(4;11)(q21;q23) is very rare. It is characterized by mixed-lineage leukemia and has the potential for lineage switching during the treatment course. We report the disease course of a patient with B-ALL with t(4;11)(q21;q23) to demonstrate that close monitoring of cell morphology and immunophenotyping is necessary to capture the lineage switch at an early stage. Cell morphology, immunophenotyping, and cytogenetics were used to evaluate the patient's disease status. A 36-year-old woman was diagnosed with B-ALL with t(4;11)(q21;q23), which encodes the KMT2A::AFF1 fusion. After the initial induction chemotherapy, her disease remained refractory, and the patient received salvage immunotherapy with blinatumomab and inotuzumab ozogamicin. However, the ALL did not respond. Repeated bone marrow examinations unexpectedly revealed the emergence of a major population of monoblasts, in addition to a minor population of the original B lymphoblasts. The patient was diagnosed with disease evolution from B-ALL to mixed-phenotype acute leukemia (MPAL, B/myeloid). We present this case to highlight the potential of KMT2A-rearranged B-ALL to undergo lineage switch following B-cell targeted therapy. Patients with this kind of B-ALL should therefore be closely monitored to capture potential changes in the nature of the disease and prompt appropriate treatment.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Adulto , Femenino , Linfocitos T , Inmunoterapia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamiento farmacológico , Inotuzumab Ozogamicina
5.
J Microbiol Immunol Infect ; 55(2): 225-233, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33840606

RESUMEN

OBJECTIVES: This study aimed to provide detailed genetic characterization of Tn6636, a multidrug-resistant and composite mobile element, in clinical isolates of Staphylococcus aureus. METHODS: A total of 112 ermB-positive methicillin-susceptible S. aureus (MSSA) and 224 ermB-positive methicillin-resistant S. aureus (MRSA) isolates collected from 2000 to 2015 were tested for the presence of Tn6636. Detection of the plasmids harboring Tn6636 was performed by S1 nuclease digestion pulsed-field gel electrophoresis (PFGE) analysis, conjugation test, and whole genome sequencing (WGS). RESULTS: Prevalence of Tn6636 in MSSA is higher than that in MRSA. Ten MSSA isolates and 10 MRSA isolates carried Tn6636. The 10 MSSA isolates belonged to three sequence types (ST), including ST7 (n = 6), ST5 (n = 3), and ST59 (n = 1). The 10 MRSA isolates belonged to ST188 (n = 8) and ST965 (n = 2). Analysis of plasmid sequences revealed that Tn6636 was harbored by six different mosaic plasmids. In addition to resistance genes, some plasmids also harbored toxin genes. CONCLUSION: The presence of multi-resistant Tn6636 in plasmids of both MSSA and MRSA with various STs suggests its broad dissemination. Results indicate that Tn6636 has existed for at least 16 years in Taiwan. The mosaic plasmids harboring Tn6636 can be transferred by conjugation. Ongoing surveillance of Tn6636 is essential to avoid continued spreading of resistant plasmids.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Antibacterianos/farmacología , Humanos , Staphylococcus aureus Resistente a Meticilina/genética , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus
6.
Water Res ; 203: 117517, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34391021

RESUMEN

The degradation of pharmaceuticals by electrochemical oxidation (EO) in simulated wastewater containing multiple pharmaceuticals was compared between batch and continuous reactors. Despite the excellent efficiencies achieved in batch experiments, the practical/large-scale applications of EO-degrading amine-containing pharmaceuticals has not yet been accomplished. This paper presents the results of continuous experiments with one of the most promising electrochemical configurations of Pt/Ti electrodes before proceeding to application. In the continuous electrooxidation system (without chloride), direct oxidation on the electrode surface and oxidation by hydroxyl radicals were the main pathways. Due to their short lifespans, the radicals could not be transferred to the bulk solution, and the removal of pharmaceuticals followed the order of sulfamethoxazole (SMX) > paracetamol (PAR) > diclofenac (DIC). In the electrochlorination system (with chloride), oxidation by residual chlorine was the main pathway. The removal of pharmaceuticals followed the order of sulfamethoxazole (SMX) > diclofenac (DIC) > paracetamol (PAR). High SMX removal was realized because of the high reaction rate of SMX with free chlorine. Among the pharmaceuticals, PAR had the lowest removal because it is a neutral species with a low mass transfer rate without the attraction of electrostatic force. These results are consistent with the predictions from our previous batch-scale study, which showed that the reaction rate of dissociated compounds could be increased by the addition of electrostatic force. Furthermore, multiple coexisting pharmaceuticals, such as SMX and PAR or DIC, may form dimers that can be transferred to complex structures and cause higher toxicity.


Asunto(s)
Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Aminas , Oxidación-Reducción , Sulfametoxazol , Aguas Residuales , Contaminantes Químicos del Agua/análisis
7.
Int J Occup Saf Ergon ; 27(2): 351-357, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30822268

RESUMEN

To design a comprehensive health and safety management performance system, extant literature on the health and safety performance indicators of and management systems for the application of occupational health and safety management systems was reviewed; additionally, the provisions of occupational health and safety laws were examined with a total of three main categories, including 28 active safety and health management performance categories. In the present study, health and safety management performance was evaluated by food manufacturing industry employees. An active performance evaluation questionnaire was developed by adopting the Delphi method to seek professional and expert opinion. With food manufacturing workers as participants, an in-depth discussion was conducted regarding the status of active health and safety performance indicators. Six active health and safety performance indicators were determined: emergency response; change management; procurement management; communication; prevention management; security behavior. These performance indicators have not been sufficiently implemented and require improvement.


Asunto(s)
Salud Laboral , Industria de Procesamiento de Alimentos , Humanos , Industria Manufacturera , Administración de la Seguridad , Encuestas y Cuestionarios
8.
Chemosphere ; 266: 128949, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33280843

RESUMEN

Perfluorooctanoic acid (PFOA) was separated and recovered using a foam flotation process aided by cationic surfactants. The PFOA removal efficiency was in the following decreasing order: OTAB (C8TAB) > DTAB (C10TAB) > CTAB (C16TAB) > TBAB, which indicates that cationic surfactants with an alkyl chain that had a similar length to that of PFOA had higher affinities to PFOA. PFOA removal slightly decreased with increasing ionic strength of the surfactant but did not change with the pH. PFOA could be completely removed in 20 min with 1.25 mM of OTAB in actual wastewater. The energy yield value of foam flotation with a cationic surfactant was much higher than those of other methods, which means that using foam flotation with a cationic surfactant as the collector is a simple, fast, and energy-efficient method to separate and recover PFOA from dilute water solutions.


Asunto(s)
Fluorocarburos , Tensoactivos , Caprilatos , Aguas Residuales
9.
Artículo en Inglés | MEDLINE | ID: mdl-32585957

RESUMEN

Amine-containing pharmaceuticals are the most often detected pharmaceuticals in wastewater and ambient aquatic environments. They can usually be degraded by manganese oxide (MnO2), which is a common natural oxidant in soils. Surfactants often coexist with pharmaceuticals in wastewater. Some amine-containing pharmaceuticals, such as diclofenac (DIC), are acidic and are thus ionic compounds in neutral conditions. These compounds, therefore, have similar properties to surfactants. Surfactants, thus, may influence the adsorption and degradation processes of DIC by MnO2. The effect of the type of surfactant on the degradation of DIC by MnO2 was investigated in this study with the addition of two common biodegradable surfactants (cetyltrimethyl-ammonium bromide (CTAB) and sodium dodecylsulfate (SDS)). The results indicated that the cationic surfactant (CTAB) significantly increased the degradation rate in neutral and alkaline conditions. On the other hand, the anionic surfactant (SDS) slightly increased the DIC removal rate in an acidic condition but significantly decreased the removal in neutral and alkaline conditions. Coexisting cationic surfactants not only influenced the kinetics but also altered the transformation mechanism of DIC by MnO2. Decarboxylation is the main transformation mechanism of DIC in the presence of CTAB, while both decarboxylation and hydroxylation are the main transformation mechanisms in the absence of CTAB.


Asunto(s)
Diclofenaco/farmacocinética , Compuestos de Manganeso/farmacología , Tensoactivos/farmacología , Diclofenaco/química , Humanos , Óxidos , Tensoactivos/química
10.
Water Res ; 155: 56-65, 2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-30831424

RESUMEN

Amine-containing pharmaceuticals such as acetaminophen, diclofenac, and sulfamethoxazole are the most often detected pharmaceuticals in wastewater and other aquatic environments. Amine-containing pharmaceuticals can be effectively removed by chlorination. These drugs, however, may coexist in wastewater. Thus, they may compete with each other, and their chlorinated products may react with each other to form new products. In this study, competitive effects of the above three amine-containing pharmaceuticals by chlorination and their products were investigated. The priority of chlorination of these compounds was dependent upon the pH of the solution, due to the dissociation of the compounds and hypochlorite. It followed the order of sulfamethoxazole > diclofenac > acetaminophen in an acidic condition, the order of sulfamethoxazole > acetaminophen > diclofenac in a neutral condition, and the order of sulfamethoxazole ≈ acetaminophen > diclofenac in an alkaline condition. Some of the chlorinated products in single- and multiple-compound systems were the same. Dimers of sulfamethoxazole and its chlorinated products, however, were not found, but dimers of sulfamethoxazole and acetaminophen or diclofenac were found in multiple-compound systems. This finding is important because it means that new products may be produced if different amine-containing pharmaceuticals react with free chlorine simultaneously.


Asunto(s)
Halogenación , Contaminantes Químicos del Agua , Diclofenaco , Sulfametoxazol , Aguas Residuales
11.
J Hazard Mater ; 366: 592-605, 2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30576998

RESUMEN

This study investigated the direct and indirect electro-oxidation of amine-containing pharmaceuticals (acetaminophen (ACT), diclofenac (DIC), and sulfamethoxazole (SMX)) by using graphite electrodes, and to compare the influence by using different electrolytes (Na2SO4 and NaCl). Under the optimum conditions of current (I) at 0.5 A, in direct system, 74.3%, 90.0%, 81.6% of ACT, DIC, and SMX were respectively removed after 60 min (k = 0.023, 0.037, 0.027 min-1), 48.9%, 85.9%, 68.2% of TOC respectively removed after reaction time. In contrast, at the same current intensity, in indirect system, ACT, DIC, and SMX were eliminated within 30 min (k = 0.117, 0.307, 0.170 min-1), 89.6%, 92.6%, 99.6% of TOC respectively removed after reaction time. The results indicated that the dissociated compounds were attracted to the anode due to electrostatic forces and had higher mass transformation rates in the direct electro-oxidation process. According to the cyclic voltammogram, indirect oxidation occurred when active chlorine species were generated from chloride ions anodically to destroy pollutants. Based on intermediates detected during electro-oxidation treatment by ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS), only oxidized intermediates were found in the direct oxidation system, while both oxidized and chlorinated intermediates were found in the indirect oxidation system.


Asunto(s)
Aminas/análisis , Electrodos , Grafito/química , Preparaciones Farmacéuticas/química , Oxidación-Reducción
12.
Int J Dev Biol ; 62(9-10): 613-621, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30378385

RESUMEN

Cell morphology is recognized as an important hallmark of neural cells. During the differentiation of human pluripotent stem cells (hPSCs) into neural cells, cell morphology changes dynamically. Therefore, characterization of the morphology of cells during this period is important to improve our understanding of the differentiation and development of neural cells. General methods for the directed induction of hPSCs include the steps of multi-cellular aggregation or high-density cell culture, particularly at the early phase of neural differentiation, and therefore, the morphology of each differentiating cell is difficult to recognize. Here, we have developed a new method for the directed differentiation of neuroepithelial-like cells (NELCs) from hPSCs at a low cell density in an adherent monolayer culture, as well as an image-processing algorithm to evaluate the cell morphology of differentiating NELCs, in order to follow cell morphology during the differentiation of hPSCs into NELCs. Using these methods, the morphological transition of differentiating cells was observed in real time using phase contrast imaging and then quantified. Because cell morphology is also considered an inherent biological marker of neural cells cultured in vitro, this method is potentially useful to study the mechanisms underlying neural cell differentiation.


Asunto(s)
Diferenciación Celular , Células Madre Pluripotentes Inducidas/citología , Células Neuroepiteliales/citología , Neurogénesis , Neuronas/citología , Biomarcadores/metabolismo , Técnicas de Cultivo de Célula , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Células Neuroepiteliales/metabolismo , Neuronas/metabolismo
13.
Exp Cell Res ; 352(2): 333-345, 2017 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-28215634

RESUMEN

Limited growth potential, narrow ranges of sources, and difference in variability and functions from batch to batch of primary hepatocytes cause a problem for predicting drug-induced hepatotoxicity during drug development. Human pluripotent stem cell (hPSC)-derived hepatocyte-like cells in vitro are expected as a tool for predicting drug-induced hepatotoxicity. Several studies have already reported efficient methods for differentiating hPSCs into hepatocyte-like cells, however its differentiation process is time-consuming, labor-intensive, cost-intensive, and unstable. In order to solve this problem, expansion culture for hPSC-derived hepatic progenitor cells, including hepatic stem cells and hepatoblasts which can self-renewal and differentiate into hepatocytes should be valuable as a source of hepatocytes. However, the mechanisms of the expansion of hPSC-derived hepatic progenitor cells are not yet fully understood. In this study, to isolate hPSC-derived hepatic progenitor cells, we tried to develop serum-free growth factor defined culture conditions using defined components. Our culture conditions were able to isolate and grow hPSC-derived hepatic progenitor cells which could differentiate into hepatocyte-like cells through hepatoblast-like cells. We have confirmed that the hepatocyte-like cells prepared by our methods were able to increase gene expression of cytochrome P450 enzymes upon encountering rifampicin, phenobarbital, or omeprazole. The isolation and expansion of hPSC-derived hepatic progenitor cells in defined culture conditions should have advantages in terms of detecting accurate effects of exogenous factors on hepatic lineage differentiation, understanding mechanisms underlying self-renewal ability of hepatic progenitor cells, and stably supplying functional hepatic cells.


Asunto(s)
Técnicas de Reprogramación Celular/métodos , Células Madre Embrionarias/citología , Hepatocitos/citología , Células Madre Pluripotentes/citología , Diferenciación Celular , Células Cultivadas , Medio de Cultivo Libre de Suero/farmacología , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Células Madre Embrionarias/efectos de los fármacos , Células Madre Embrionarias/metabolismo , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intercelular/farmacología , Células Madre Pluripotentes/efectos de los fármacos , Células Madre Pluripotentes/metabolismo
14.
Nature ; 486(7403): 415-9, 2012 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-22722204

RESUMEN

The modification of DNA by 5-methylcytosine (5mC) has essential roles in cell differentiation and development through epigenetic gene regulation. 5mC can be converted to another modified base, 5-hydroxymethylcytosine (5hmC), by the tet methylcytosine dioxygenase (Tet) family of enzymes. Notably, the balance between 5hmC and 5mC in the genome is linked with cell-differentiation processes such as pluripotency and lineage commitment. We have previously reported that the maternal factor PGC7 (also known as Dppa3, Stella) is required for the maintenance of DNA methylation in early embryogenesis, and protects 5mC from conversion to 5hmC in the maternal genome. Here we show that PGC7 protects 5mC from Tet3-mediated conversion to 5hmC by binding to maternal chromatin containing dimethylated histone H3 lysine 9 (H3K9me2) in mice. In addition, imprinted loci that are marked with H3K9me2 in mature sperm are protected by PGC7 binding in early embryogenesis. This type of regulatory mechanism could be involved in DNA modifications in somatic cells as well as in early embryos.


Asunto(s)
5-Metilcitosina/metabolismo , Citosina/análogos & derivados , Embrión de Mamíferos/metabolismo , Histonas/química , Histonas/metabolismo , Proteínas Represoras/metabolismo , Animales , Cromatina/química , Cromatina/metabolismo , Proteínas Cromosómicas no Histona , Citosina/metabolismo , Metilación de ADN , Proteínas de Unión al ADN/metabolismo , Dioxigenasas , Embrión de Mamíferos/embriología , Desarrollo Embrionario , Femenino , Impresión Genómica/genética , Lisina/química , Lisina/metabolismo , Masculino , Metilación , Ratones , Unión Proteica/efectos de los fármacos , Proteínas Proto-Oncogénicas/metabolismo , ARN Largo no Codificante , ARN no Traducido/genética , Espermatozoides/metabolismo , ras-GRF1/genética
15.
Biol Reprod ; 86(2): 40, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22034526

RESUMEN

Dynamic alterations in chromatin configuration occur in mammalian oocytogenesis. Based on chromatin configuration patterns, fully grown oocytes are classified into two types. One is surrounded nucleolus (SN)-type and the other is nonsurrounded nucleolus (NSN)-type oocytes. Although chromatin condensation during the transition from NSN- to SN-type oocytes is a prerequisite for normal early embryonic development, the molecular mechanisms remain unclear. In this study, we analyzed the role of DPPA3 (also known as PGC7/Stella) in this transition using Dppa3-null oocytes. The NSN-to-SN transition was significantly impaired, and transcriptional repression was incomplete in the Dppa3-null oocytes. Additionally, we revealed that prior transcriptional repression was necessary for the NSN-to-SN transition. These findings demonstrate that DPPA3 is an essential factor for the production of functional oocytes through transcriptional repression and chromatin condensation.


Asunto(s)
Cromatina/fisiología , Oocitos/fisiología , Oogénesis/fisiología , Proteínas Represoras/fisiología , Animales , Nucléolo Celular/fisiología , Proteínas Cromosómicas no Histona , Femenino , Heterocromatina/fisiología , Histonas/fisiología , Ratones , Ratones Noqueados , Oocitos/citología , Proteínas Represoras/deficiencia , Proteínas Represoras/genética , Transcripción Genética/fisiología
16.
Hepatol Res ; 39(6): 625-31, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19260995

RESUMEN

Severe intrahepatic cholestasis with low serum gamma-glutamyltranspeptidase (gamma-GT) activity is exceptionally rare in adult patients, and its association with multi-genetic alterations of bile salt transporters has not been reported. We investigated a 25-year-old man presenting with a four-year history of jaundice. Laboratory and radiographic examinations revealed clinical pictures of progressive intrahepatic cholestasis with low gamma-GT. Serial liver histopathology demonstrated cirrhosis resulting from progressive persistent cholestatic injury. Genetic sequencing studies for the entire coding exons of ATP8B1 and ABCB11 uncovered a heterozygous missense mutation 1798 C->T (R600W) in ATP8B1, and a homozygous nucleotide substitution 1331 T->C (V444A) in ABCB11. In conclusion, this is a rare case of adult onset progressive intrahepatic cholestasis with low gamma-GT associated with heterozygous ATP8B1 mutation and homozygous ABCB11 polymorphism. Further studies are necessary to investigate the impact of heterozygous R600W mutation and whether other cholestatic disorders are multi-genetic.

17.
J Gastroenterol Hepatol ; 23(9): 1390-3, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18853996

RESUMEN

BACKGROUND AND AIM: Progressive familial intrahepatic cholestasis type 2 (PFIC2) results from genetic defects of the hepatobiliary bile salt export pump (BSEP, ABCB11) at chromosome 2q24. Patients with progressive cholestasis and liver cirrhosis usually need liver transplantation in the first decade. Mutations in ABCB11 are also associated with benign recurrent intrahepatic cholestasis type 2 and intrahepatic cholestasis of pregnancy in adult patients. We aimed to make the prenatal diagnosis of PFIC2. METHODS: Genetic diagnosis was performed by genomic DNA analysis. Prenatal genetic diagnosis was made by fetal amniotic DNA and chorionic DNA analysis. RESULTS: We report on two families of PFIC2 with inherited compound heterozygous mutations of ABCB11 (M183V and R303K in Family 1, V284L and 1145delC in Family 2) from the parents. An infant with heterozygous M183V mutation was later born healthy in Family 1. A fetus with compound heterozygous missense mutation V284L and 1145delC was terminated in Family 2. CONCLUSION: Prenatal diagnosis of PFIC2 was helpful to prevent further affected children in families with this fatal disease.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Colestasis Intrahepática/diagnóstico , Pruebas Genéticas , Mutación , Diagnóstico Prenatal/métodos , Miembro 11 de la Subfamilia B de Transportador de Casetes de Unión al ATP , Aborto Inducido , Amniocentesis , Colestasis Intrahepática/genética , Muestra de la Vellosidad Coriónica , Análisis Mutacional de ADN , Progresión de la Enfermedad , Resultado Fatal , Femenino , Heterocigoto , Humanos , Recién Nacido , Nacimiento Vivo , Masculino , Linaje , Embarazo
18.
J Pediatr ; 153(6): 825-32, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18692205

RESUMEN

OBJECTIVE: To determine if specific mutations were present in Asian patients with progressive familial intrahepatic cholestasis (PFIC) type 2 caused by defects in bile salt export pump (BSEP), encoded by ABCB11. STUDY DESIGN: A combination of denaturing high-performance liquid chromatography (DHPLC) and direct sequencing was used to screen ABCB11 mutations in 18 Taiwanese patients with low gamma-glutamyltransferase PFIC or benign recurrent intrahepatic cholestasis (BRIC). Polymorphisms were also analyzed in patients with PFIC (n = 21), neonatal cholestasis (n = 23), and control subjects (n = 88). RESULTS: Seven mutations in 4 of 16 patients with PFIC from different families were detected by DHPLC, including M183V, V284L, R303K, R487H, W493X, G1004D, and 1145delC. G1004D was found in a patient with BRIC. L827I was found in another patient with neonatal cholestasis. Absent or defective BSEP staining was found in the liver of patients with mutations. Polymorphisms V444A and A865V, with an allele frequencies 75.6% and 0.6%, respectively, were found in our population. No differences were found between patients with cholestasis and control subjects. CONCLUSIONS: One-fourth of Taiwanese patients with PFIC/BRIC had compound heterozygous or single heterozygous ABCB11 mutations without hot spots. All of the mutations were different from those detected in Western countries.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Colestasis Intrahepática/genética , Mutación/genética , Miembro 11 de la Subfamilia B de Transportador de Casetes de Unión al ATP , Colestasis Intrahepática/diagnóstico , Colestasis Intrahepática/enzimología , Cromatografía Líquida de Alta Presión , Exones/genética , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Polimorfismo Genético , Taiwán
19.
Pediatr Res ; 63(6): 667-73, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18327154

RESUMEN

To investigate how the liver adapts to chronic obstructive cholestasis, liver samples from infants with early- and late-stage cholestasis were analyzed for changes in the levels of hepatocyte transporters and nuclear receptors. At early-stage cholestasis, most canalicular transporters and sinusoidal uptake transporters were downregulated, including bile salt export pump (BSEP, ABCB11), multidrug resistant protein 3 (MDR3, ABCB4), multidrug-resistant associated protein 2 (MRP2, ABCC2), sodium-dependent taurocholate cotransporting polypeptide (NTCP, SLC10A1), organic anion transporter (OATP, SLCO1A2), and nuclear receptor farnesoid X receptor (FXR, NR1H4). At late-stage cholestasis, FXR-BSEP levels returned to normal, MDR3 and MDR1 (ABCB1) were upregulated, and MRP-2 was downregulated. In addition, alternative sinusoidal efflux transporters, organic solute transporter alpha/beta (OSTalpha/beta) and MRP4 were upregulated, and pregnane X receptor (PXR, NR1I2) levels decreased. Cytochrome enzyme P450 7A1 was markedly downregulated at both early and late-stage cholestasis. An analysis of the long-term prognosis of 18 patients revealed lower PXR and constitutive androstane receptor (CAR, NR1I3) levels in the poor prognosis group. In conclusion, at long-term cholestasis, hepatocyte bile efflux was through sinusoidal and canalicular transporters, with FXR-BSEP levels maintained and PXR downregulated. Low PXR and CAR levels were associated with poor prognosis.


Asunto(s)
Atresia Biliar/complicaciones , Colestasis Intrahepática/metabolismo , Hepatocitos/química , Hígado/química , Proteínas de Transporte de Membrana/análisis , Receptores Citoplasmáticos y Nucleares/análisis , Adaptación Fisiológica , Bilis/metabolismo , Atresia Biliar/metabolismo , Atresia Biliar/fisiopatología , Atresia Biliar/cirugía , Colestasis Intrahepática/etiología , Colestasis Intrahepática/fisiopatología , Colestasis Intrahepática/cirugía , Receptor de Androstano Constitutivo , Progresión de la Enfermedad , Femenino , Hepatocitos/patología , Humanos , Lactante , Recién Nacido , Hígado/patología , Hígado/fisiopatología , Hígado/cirugía , Trasplante de Hígado , Masculino , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Microscopía Fluorescente , Proteína 2 Asociada a Resistencia a Múltiples Medicamentos , Pronóstico , ARN Mensajero/análisis , Receptores Citoplasmáticos y Nucleares/genética
20.
Hepatogastroenterology ; 53(68): 262-5, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16608036

RESUMEN

BACKGROUND/AIMS: Pituitary tumor-transforming gene-1, a recently identified proto-oncogene, was reported to be highly expressed in various tumors, such as tumors of the pituitary gland, adrenal gland, colon, ovary, endometrium, uterus, and kidney. The purpose of this study was to investigate the clinicopathologic significance of PTTG1 expression in hepatocellular carcinoma. METHODOLOGY: Expression of PTTG1 mRNA was evaluated by RT-PCR in 147 HCCs and 103 paired nontumorous liver tissues. RESULTS: PTTG1 was found overexpressed in 80 of 147 (61%) HCCs. Overexpression of PTTG1 correlated with alpha-fetoprotein elevation (p<0.022) and higher tumor stage (stage IIIB-IV) tumors (p<0.009), but not with tumor grade, size, and survival. CONCLUSIONS: The results show that PTTG1 is overexpressed frequently in HCC, and correlated high stage tumors, indicating that overexpression of PTTG1 plays a role in the development and progression of HCC.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Femenino , Genes p53/genética , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Mutación , Proteínas de Neoplasias/genética , Estadificación de Neoplasias , Proto-Oncogenes Mas , ARN Mensajero/metabolismo , Securina , beta Catenina/genética
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