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C Villalva

Publications and source records attributed to C Villalva.

4 recordsLinked to original sources

Increased yield of PCR products by addition of T4 gene 32 protein to the SMART PCR cDNA synthesis system.

Under certain conditions, T4 gene 32 protein is known to increase the efficiency of different enzymes, such as Taq DNA polymerase, reverse transcriptase, and telomerase. In this study, we compared the efficiency of the SMART PCR cDNA synthesis kit with and without the T4 gene 32 protein. The use of this cDNA synthesis procedure, in combination with T4 gene 32 protein, increases the yield of RT-PCR products from approximately 90% to 150%. This effect is even observed for long mRNA templates and low concentrations of total RNA (25 ng). Therefore, we suggest the addition of T4 gene 32 protein in the RT-PCR mixture to increase the efficiency of cDNA synthesis, particularly in cases when low amounts of tissue are used.

DNA, Complementary↗

[Gene expression profiling by suppression subtractive hybridization (SSH): a example for its application to the study of lymphomas].

Suppression subtractive hybridization (SSH) was used to isolate genes that were differentially expressed in anaplastic lymphoma kinase (ALK)-positive and ALK-negative anaplastic large cell lymphoma. In addition, this approach was applied to Hodgkin's disease cases with different clinical outcomes. SSH combines a normalization step that equalizes the abundance of cDNAs within the sequences to be tested and a subtraction step that excludes the common sequences between the target and the control. In a model system, the SSH technique enriches for rare sequences up to 5,000-fold in one round. We have isolated several genes whose expression varied significantly with regard to the tumour subtypes. There were different genes with known or unknown functions. We aim to compare the results of the SSH approach with those obtained with high density filters. In a near future, we would like to design DNA chips specific of each pathology that could be used for clinical purposes (evaluation of prognosis and therapeutic response).

Gene Expression Profiling↗

CT attenuation values and enhancing characteristics of thoracoabdominal lymphomatous adenopathies.

OBJECTIVE: Thoracoabdominal lymphomatous adenopathies have been described as homogeneous and typically showing little enhancement on postcontrast CT. After observing pronounced adenopathic contrast enhancement in one patient with lymphoma, we prospectively investigated the CT enhancing characteristics and attenuation values of pathologic thoracic and abdominal lymph nodes in 25 patients with lymphoma. MATERIALS AND METHODS: Unenhanced CT of the chest, abdomen and pelvis was performed in all cases. The enhancing characteristics and attenuation values of the largest node or group of nodes were evaluated at 1, 2, 5, and 10 min after a 100 ml intravenous bolus injection of contrast medium. RESULTS: On unenhanced CT the nodes were of soft-tissue attenuation (42 +/- 5 HU) in 23 cases and of low attenuation (31 and 28 HU) in 2 cases. The maximum enhancement was achieved at 1 or 2 min postinjection and was low (16 +/- 6 HU) or moderate (31 +/- 6 HU) in 21 cases and pronounced (61 +/- 5 HU) in 4. The patterns of enhancement were classified as homogeneous (no. = 23) inhomogeneous (no. = 1), and peripheral (no. = 1). CONCLUSION: Thoracic and abdominal lymphomatous adenopathies are usually of soft-tissue attenuation on unenhanced CT and can show slight, moderate, or even pronounced enhancement on postcontrast CT.

Adult↗