Conventional and Molecular Diagnosis of Drug-Sensitive and Drug-Resistant Pulmonary Tuberculosis

Tuberculosis is a transmissible disease, which is primarily caused by the bacteria Mycobacterium tuberculosis and by other Mycobacterium species, forming the Mycobacterium tuberculosis complex. Until the end of the 20th Century, most cases of pulmonary tuberculosis were considered curable. Nevertheless, the rising of tuberculosis resistant to first- and second-line anti-tuberculous drugs is threatening the world’s tuberculosis control programs. Due to this fact, the World Health Organization and other public health institutions recommended applying the conventional methods, affordable by low-incoming countries, to diagnose tuberculosis and to develop faster and more sensitive and specific methods to identify M. tuberculosis and determine their condition of anti-tuberculous drug resistance or drug sensitivity. In this chapter, we mention the most used conventional and molecular methods designed to identify M. tuberculosis and to determine their drug sensitivity or drug resistance. We also briefly describe the fundamentals of methods and its advantages and limitations

Understanding the colon cancer stem cells and perspectives on treatment

An area of research that has been recently gaining attention is the relationship between cancer stem cell (CSC) biology and chemo-resistance in colon cancer patients. It is well recognized that tumor initiation, growth, invasion and metastasis are promoted by CSCs. An important reason for the widespread interest in the CSC model is that it can comprehensibly explain essential and poorly understood clinical events, such as therapy resistance, minimal residual disease, and tumor recurrence. This review discusses the recent advances in colon cancer stem cell research, the genes responsible for CSC chemoresistance, and new therapies against CSCs

Disección transcripcional del Locus GH del genoma humano

El locus de la hormona del crecimiento humano (hGH) presenta variaciones en los niveles de expre- sión en algunos de sus componentes hasta en tres órdenes de magnitud. Este estudio comparó deleciones (140 a 3,100 pb) y la fuerza de transcrip- ción de todos los promotores del locus con un gen reportero (hGH-N) mediante expresión transitoria. Los promotores largos tuvieron mayor expresión, paradójicamente hGH-V fue uno de los más acti- vos. Se detectaron tres elementos promotores ne- gativos y se evaluó la activación transcripcional di- ferencial para los diferentes promotores, mediante su respuesta a la acción de hormonas y cotransfec- ción de vectores expresores de factores transcripcionales

Proteoma y vías de señalización inducidas por AAS en células que expresan el VHC

RESUMEN El AAS disminuye la expresión del VHC por mecanismos aún desconocidos. Se compararon perfiles de expresión proteómica en células de hepatocarcinoma (Huh7) y células que expresan proteínas no estructuradas del VHC (Huh7-VHC) tratadas con AAS 4mM. Los perfiles obtenidos mediante electroforesis bidimensional fueron analizados por pI y PM. Se identificaron diferentes patrones entre células Huh7- VHC tratadas y no tratadas con AAS. Entre las proteínas diferencialmente expresadas encontramos proteínas relacionadas con proliferación celular (MTMR6, FAM22, HDGF y HCF-1) y sobreexpresión de angiotensina, PI4KA y STAT-1. A las 72h, identificamos sobreexpresión de adenil-succinato sintasa, 2’-3’-di-deoxiadenosina, proteína ligasa de ubiquitina E6A, adenilsuccinato-liasa y nibrina. El AAS induce diferentes patrones proteicos en células Huh7- VHC, promoviendo la activación de proteínas relacionadas con progresión celular, reparación de DNA, inhibición de apoptosis y estimulación del crecimiento. ABSTRACT ASA has been shown to downregulate HCV expression; however, the involved mechanisms are unknown. We used proteomic analysis to compare protein expression profiles between human hepatocarcinome cells (Huh7) and Huh7-HCV cells harboring expression of non-structural HCV proteins to elucidate the mechanisms involved in ASAmediated downregulation of HCV replication. Cell lines were treated with 4 mM ASA and harvested to isolate total proteins, which were resolved by 2-DE. Gels were analyzed and proteins elucidated by pI and MW patterns. Different protein patterns among hepatocytes expressing HCV-proteins in ASA treated and untreated cells were found. Among proteins differentially expressed we found proteins related to cellular proliferation (MTMR6, FAM22, HDGF y HCF-1) and overexpression of angiotensin (PI4KA y STAT-1). We found that ASA induces different protein patterns in Huh7-HCV cells promoting activation of proteins involved in cell progression, repair of double strand breaks, proliferation, inhibition of apoptosis and growth stimulation at the same time that it decreased HCV expression

El etanol aumenta la replicación y expresión génica del VHC

El etanol acelera la progresión del daño hepático en los pacientes con hepatitis C crónica. Se utilizó el sistema de replicones subgenómicos del VHC para evaluar el efecto del etanol en la replicación y expresión génica del VHC. Se observó que el etanol aumentó los niveles del RNA y de las proteínas virales. Se observó que el etanol aumentó la expresión y actividad de la proteína COX-2 en las células Huh7 replicón, mientras que el AAS bloqueó dicho efecto. Lo que sugiere que, probablemente, la COX-2 modula el efecto del etanol en la replicación del VHC

Flourensia cernua: Hexane Extracts a Very Active Mycobactericidal Fraction from an Inactive Leaf Decoction against Pansensitive and Panresistant Mycobacterium tuberculosis

The efficacy of decoction in extracting mycobactericidal compounds from Flourensia cernua (Hojasé) leaves and fractionation with solvents having ascending polarity was compared with that of (i) ethanol extraction by still maceration, extraction with a Soxhlet device, shake-assisted maceration, or ultrasound-assisted maceration, followed by fractionation with n-hexane, ethyl acetate, and n-butanol; (ii) sequential extraction with n-hexane, ethyl acetate, and n-butanol, by still maceration, using a Soxhlet device, shake-assisted maceration, or ultrasound-assisted maceration. The in vitro mycobactericidal activity of each preparation was measured against drug-sensitive (SMtb) and drug-resistant (RMtb) Mycobacterium tuberculosis strains. The results of which were expressed as absolute mycobactericidal activity (AMA). These data were normalized to the ΣAMA of the decoction fraction set. Although decoction was inactive, the anti-RMtb normalized ΣAMA (NAMA) of its fractions was comparable with the anti-RMtb NAMA of the still maceration extracts and significantly higher than the anti-SMtb and anti-RMtb NAMAs of every other ethanol extract and serial extract and fraction. Hexane extracted, from decoction, material having 55.17% and 92.62% of antituberculosis activity against SMtb and RMtb, respectively. Although the mycobactericidal activity of decoction is undetectable; its efficacy in extracting F. cernua active metabolites against M. tuberculosis is substantially greater than almost all pharmacognostic methods

Circulating microRNA expression profile in B-cell acute lymphoblastic leukemia

BACKGROUND: Acute lymphoblastic leukemia (ALL) is a highly diverse disease characterized by cytogenetic and molecularabnormalities, including altered microRNA (miRNA) expression signatures. AIM: We perform and validate a plasma miRNA expression profiling to identify potential miRNA involved in leukemogenesis METHODS: MiRNA expression profiling assay was realized in 39 B-ALL and 7 normal control plasma samples using TaqMan Low Density Array (TLDA) plates on Applied Biosystems 7900 HT Fast Real-Time PCR System. MiRNA validation was done for six miRNA differentially expressed by quantitative real-time PCR. RESULTS: Seventy-seven circulating miRNA differentially expressed: hsa-miR-511, -222, and -34a were overexpressed, whereas hsa-miR-199a-3p, -223, -221, and -26a were underexpressed (p values < 0.005 for both sets). According to operating characteristic curve analysis, hsa-miR-511 was the most valuable biomarker for distinguishing B-ALL from normal controls,with an area under curve value of 1 and 100% for sensitivity, and specificity respectively. CONCLUSIONS: Measuring circulating levels of specific miRNA implicated in regulation of cell differentiation and/or cell proliferation such as hsa-miRNA-511, offers high sensitivity and specificity in B-ALL detection and may be potentially useful for detection of disease progression, as indicator of therapeutic response, and in the assessment of biological and/or therapeutic targets for patients with B-ALL

Ingeniería tisular en la reparación de las lesiones articulares

La ingeniería tisular es una rama de la bioingeniería, cuyo principio básico es la utilización de un sustrato celular vivo, aunado a un diseño y manipulación del medio extracelular para crear bioimplantes destinados a reparar, reemplazar, mantener u optimizar el funcionamiento de órganos o tejidos lesionados. Las técnicas de ingeniería tisular utilizadas para la reparación de cartílago son dos: los injertos osteocondrales y el trasplante de condrocitos. El cultivo e implantación de condrocitos autólogos es una alternativa para la reparación de los defectos articulares; esta es una de las primeras biotécnicas aplicadas a la cirugía ortopédica. Los estudios originales de ésta fueron realizados en conejos con buenos resultados en 82% de los casos. El desarrollo de estos procesos ha traído consigo otras líneas de investigación, entre ellas, el estudio de los factores de crecimiento, de células madre o tallo y la terapia génic