Validation of appropriate reference genes for gene expression studies in human thyroid gland using real-time RT-PCR.

BACKGROUND: Gene-expression analysis is increasingly important in biological research, with real-time reverse transcription PCR (qRT-PCR) becoming the method of choice. The selection of reference genes is critical for gene expression studies because the expression of these genes may vary among tissues or cells and may change under certain circumstances. However there has not been any study that compares the stability of these reference genes in human thyroid specimens. Therefore, the authors studied the stability values and the appropriate reference genes expressed in thyroid specimens. MATERIAL AND METHOD: 25 human thyroid specimens were prospectively collected and extracted for their RNA. The candidate reference genes (hypoxanthine phosphoribosyl-transferase1 (HPRT1), ribosomal protein LI3a (RPLIA), beta-2-micro-globulin (B2M), beta-actin (ACTB) and glyceraldehyde-3-phosphate dehydrogenase (GAPD)) were amplified from these thyroid specimens using real-time RT-PCR. The stabilities of these candidate reference genes were analyzed using Normfinder software. RESULTS: The authors found that HPRT1 has the highest stability value (40.38 x 10(9)) while GAPD has the lowest stability value (85.46 x 10(7)). Therefore GAPD is the most stably expressed gene in thyroid specimens. CONCLUSION: Of the 5 genes studied, GAPD was found to be the best reference gene for gene expression studies in the thyroid gland. The present results may facilitate the choice of reference genes for expression studies in thyroid diseases.

Role of ciprofloxacin in patients with cholestasis after endoscopic retrograde cholangiopancreatography.

AIM: To determine the role of ciprofloxacin in reducing cholangitis in cholestatic patients with adequate biliary drainage after endoscopic retrograde cholangiopancreatography (ERCP). METHODS: A randomized, controlled trial was performed in 48 cholestatic patients at Rajavithi Hospital (Tertiary Referral Center for ERCP: 600 cases per year). All the 48 patients received 200 mg ciprofloxacin intravenous injection for 30 min before starting any procedures, and then were randomly divided in two groups. Twenty-two patients in study group continually received ciprofloxacin until 48 h after ERCP. Causes of biliary obstruction, bacteriology of bile and blood (in cholangitis) and clinical cholangitis were recorded. RESULTS: Forty-eight patients were enrolled and divided into continuous ciprofloxacin treatment group (n = 22) and discontinuous ciprofloxacin treatment group (n = 26). During ERCP, stones were found in 22 patients, malignant diseases in 24 patients and other pathologic lesions in 5 patients. One (4.5%) of the 22 patients who received ciprofloxacin and 2 (6.3%) of the 26 patients who discontinued ciprofloxacin after ERCP developed cholangitis (relative risk = 0.71; 95% CI = 0.14-3.65; P = 0.88). Bacterobilia was found in 27 (56.3%) out of 48 patients. E. coli and Streptococcus viridans were the most common organisms. CONCLUSION: Continual use of ciprofloxacin in patients with cholestasis after adequate biliary drainage procedures plays no role in reducing cholangitis.

Circulating hTERT mRNA as a tumor marker in cholangiocarcinoma patients.

AIM: To investigate human telomerase reverse transcriptase (hTERT) mRNA in the serum of cholangiocarcinoma patients. METHODS: The serum of thirty three cholangiocarcinoma patients, forty one benign biliary tract disease patients and ten healthy volunteers were collected and analyzed for the expression of hTERT mRNA by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). We then examined the correlation between values of serum hTERT mRNA and the pathological staging of cholangiocarcinoma. RESULTS: hTERT mRNA was detected in 28 of 33 (84.85%) of serum obtained from cholangiocarcinoma patients and 9 of 41 (21.9%) of serum obtained from benign biliary tract disease patients. hTERT mRNA was not detected in any serum obtained from healthy volunteers. on the other hand the common tumor marker, CA19-9 was detected in 20 of 33 (60.6%) of serum obtained from cholangiocarcinoma patients and 8 of 41 (19.5%) of serum obtained from benign biliary tract disease patients. However, no correlation was found between the present of serum hTERT mRNA and tumor staging. CONCLUSION: These results indicate that the detection of circulating hTERT mRNA was identified in almost all cholangiocarcinoma patients. It offers a novel tumor marker, which can be used as a complementary study for diagnosis of cholangiocarcinoma.

Total video endoscopic thyroidectomy by an axillary approach.

BACKGROUND: A permanent transverse surgical scar is an unavoidable problem after conventional thyroidectomy. Endoscopic thyroidectomy performed via an axillary approach leaves no scarring at the neck and anterior chest wall and so provides an excellent cosmetic result. The axillary scars are usually not seen when the arm is in a normal position. MATERIALS AND METHODS: From April 2001 to February 2003, we used a four-port technique to perform 45 lobectomy and isthmectomy procedures. One 12-mm port for the flexible laparoscope (EL2-TF410, Fuji Photo Optical, Tokyo, Japan) and three additional 5-mm ports for instruments and suction were inserted through the axilla on the side of the nodule. The CO(2 )insufflation pressure was set at 4 mm Hg, and in most cases, a 5-mm Johnson & Johnson Harmonic Scalpel (Ethicon Endo-Surgery, Cincinnati, Ohio, U.S.A.) was used for the dissection. RESULTS: Of 45 procedures, 44 were performed successfully. In one case, conversion to a conventional technique was required. The mean operating time was 131.2 minutes, and the mean blood loss was 51.6 mL. The recurrent laryngeal nerves were clearly identified in every case, and no case of permanent voice change occurred after surgery. In one patient, a 20-mL seroma developed on the 10th postoperative day, which was treated by simple aspiration. One patient experienced a transient voice change. The patients were discharged on average at 2.9 days after the operation. CONCLUSIONS: Endoscopic thyroidectomy by an axillary approach to manage benign thyroid disease is feasible and safe and provides promising cosmetic results. We think that this approach may play an important role in the near future.