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1.
Oncogene ; 33(10): 1265-73, 2014 Mar 06.
Article in English | MEDLINE | ID: mdl-23524582

ABSTRACT

The stromal compartment surrounding epithelial-derived pancreatic tumors is thought to have a key role in the aggressive phenotype of this malignancy. Emerging evidence suggests that cancer-associated fibroblasts (CAFs), the most abundant cells in the stroma of pancreatic tumors, contribute to the tumor's invasion, metastasis and resistance to therapy, but the precise molecular mechanisms that regulate CAFs behavior are poorly understood. In this study, we utilized immortalized human pancreatic CAFs to investigate molecular pathways that control the matrix-remodeling and invasion-promoting activity of CAFs. We showed previously that palladin, an actin-associated protein, is expressed at high levels in CAFs of pancreatic tumors and other solid tumors, and also in an immortalized line of human CAFs. In this study, we found that short-term exposure of CAFs to phorbol esters reduced the number of stress fibers and triggered the appearance of individual invadopodia and invadopodial rosettes in CAFs. Molecular analysis of invadopodia revealed that their composition resembled that of similar structures (that is, invadopodia and podosomes) described in other cell types. Pharmacological inhibition and small interfering RNA knockdown experiments demonstrated that protein kinase C, the small GTPase Cdc42 and palladin were necessary for the efficient assembly of invadopodia by CAFs. In addition, GTPase activity assays showed that palladin contributes to the activation of Cdc42. In mouse xenograft experiments using a mixture of CAFs and tumor cells, palladin expression in CAFs promoted the rapid growth and metastasis of human pancreatic tumor cells. Overall, these results indicate that high levels of palladin expression in CAFs enhance their ability to remodel the extracellular matrix by regulating the activity of Cdc42, which in turn promotes the assembly of matrix-degrading invadopodia in CAFs and tumor cell invasion. Together, these results identify a novel molecular signaling pathway that may provide new molecular targets for the inhibition of pancreatic cancer metastasis.


Subject(s)
Carcinoma, Pancreatic Ductal/metabolism , Cell Surface Extensions/metabolism , Cytoskeletal Proteins/physiology , Fibroblasts/metabolism , Pancreatic Neoplasms/metabolism , Phosphoproteins/physiology , Animals , Carcinoma, Pancreatic Ductal/pathology , Cell Movement , Coculture Techniques , Extracellular Matrix/metabolism , Fibroblasts/pathology , Humans , Mice , Neoplasm Invasiveness , Neoplasm Transplantation , Pancreatic Neoplasms/pathology , Pancreatic Stellate Cells/metabolism , Pancreatic Stellate Cells/pathology , Protein Transport , Tetradecanoylphorbol Acetate/pharmacology , cdc42 GTP-Binding Protein/metabolism
2.
Int J Tuberc Lung Dis ; 18(1): 79-83, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24365557

ABSTRACT

OBJECTIVE: To evaluate the effects of pulmonary tuberculosis (PTB) on the risk of subsequent acute coronary syndrome (ACS) development. METHODS: The incidence and risk factors of ACS were investigated in 10 168 newly diagnosed tuberculosis (TB) patients from Taiwan's National Health Insurance Research Database between 1997 and 2010, and 40 672 controls without TB from the general population. The follow-up period ran from the diagnosis of new TB to the date of the ACS event, censoring or 31 December 2010. RESULTS: During the follow-up period, the overall incidence of ACS was higher in TB patients than in non-TB patients (2.10 vs. 1.51 per 1000 person-years). The incidence of ACS increased by 40% in TB patients after adjusting for age, sex and co-morbidities. Male sex, age, hypertension and diabetes were independent factors for the risk of ACS development. The probability of ACS increased in the years following the TB diagnosis. CONCLUSION: This nationwide population-based cohort study provides compelling evidence that TB patients are at higher risk of developing ACS, and that the risk increases with age. Clinicians should be aware of this and strive to reduce ACS risk factors in TB patients.


Subject(s)
Acute Coronary Syndrome/epidemiology , Tuberculosis, Pulmonary/epidemiology , Acute Coronary Syndrome/diagnosis , Acute Coronary Syndrome/mortality , Adult , Aged , Chi-Square Distribution , Female , Humans , Incidence , Kaplan-Meier Estimate , Male , Middle Aged , Multivariate Analysis , Proportional Hazards Models , Retrospective Studies , Risk Assessment , Risk Factors , Taiwan/epidemiology , Time Factors , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/mortality
3.
Anal Chem ; 85(19): 9092-100, 2013 Oct 01.
Article in English | MEDLINE | ID: mdl-23947293

ABSTRACT

In this manuscript, we discuss the development and clinical use of a thermoplastic modular microsystem for the high-throughput analysis of CTCs directly from whole blood. The modular system offers some innovative features that address challenges currently associated with many CTC platforms; it can exhaustively process 7.5 mL of blood in less than 45 min with recoveries >90%. In addition, the system automates the postselection CTC processing steps and thus, significantly reduces assay turnaround time (from selection to enumeration <1.5 h as compared to >8 h for many reported CTC platforms). The system is composed of 3 functional modules including (i) a thermoplastic CTC selection module composed of high aspect ratio (30 µm × 150 µm) channels containing anti-EpCAM antibodies that is scalable in terms of throughput by employing channel numbers ranging from 50 to 320; the channel number is user selected to accommodate the volume of blood that must be processed; (ii) an impedance sensor module for label-less CTC counting; and (iii) a staining and imaging module for the placement of released cells into a 2D array within a common imaging plane for phenotypic identification. To demonstrate the utility of this system, blood samples from patients with local resectable and metastatic pancreatic ductal adenocarcinoma (PDAC) were analyzed. We demonstrate the ability to select EpCAM positive CTCs from PDAC patients in high purity (>86%) and with excellent yields (mean = 53 CTCs per mL for metastatic PDAC patients) using our modular system. In addition, we demonstrate the ability to detect CTCs in PDAC patients with local resectable disease (mean = 11 CTCs per mL).


Subject(s)
Cell Separation/methods , Microfluidic Analytical Techniques , Neoplastic Cells, Circulating/pathology , Pancreatic Neoplasms/blood , Pancreatic Neoplasms/pathology , Humans , Microfluidic Analytical Techniques/instrumentation , Phenotype , Tumor Cells, Cultured
4.
Technol Cancer Res Treat ; 12(4): 311-21, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23369156

ABSTRACT

Most pre-clinical therapy studies use the change in tumor volume as a measure for disease response. However, tumor size measurements alone may not reflect early changes in tumor physiology that occur as a response to treatment. Ultrasonic molecular imaging (USMI) and Dynamic Contrast Enhanced-Perfusion Imaging (DCE-PI) with ultrasound are two attractive alternatives to tumor volume measurements. Since these techniques can provide information prior to the appearance of gross phenotypic changes, it has been proposed that USMI and DCE-PI could be used to characterize response to treatment earlier than traditional methods. This study evaluated the ability of tumor volume measurements, DCE-PI, and USMI to characterize response to therapy in two different types of patient-derived xenografts (known responders and known non-responders). For both responders and non-responders, 7 animals received a dose of 30 mg/kg of MLN8237, an investigational aurora-A kinase inhibitor, for 14 days or a vehicle control. Volumetric USMI (target integrin:α av ß3) and DCE-PI were performed on day 0, day 2, day 7, and day 14 in the same animals. For USMI, day 2 was the earliest point at which there was a statistical difference between the untreated and treated populations in the responder cohort (Untreated: 1.20 ±â€…0.53 vs. Treated: 0.49 ±â€…0.40; p < 0.05). In contrast, statistically significant differences between the untreated and treated populations as detected using DCE-PI were not observed until day 14 (Untreated: 0.94 ±â€…0.23 vs. Treated: 1.31 ±â€…0.22; p < 0.05). Volume measurements alone suggested no statistical differences between treated and untreated populations at any readpoint. Monitoring volumetric changes is the "gold standard" for evaluating treatment in pre-clinical studies, however, our data suggests that volumetric USMI and DCE-PI may be used to earlier classify and robustly characterize tumor response.


Subject(s)
Molecular Imaging/methods , Perfusion Imaging/methods , Tumor Burden , Xenograft Model Antitumor Assays , Animals , Azepines/therapeutic use , Contrast Media , Humans , Imaging, Three-Dimensional , Mice , Pyrimidines/therapeutic use , Ultrasonics
5.
Br J Surg ; 94(4): 466-72, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17330243

ABSTRACT

BACKGROUND: Blood transfusion is thought to have an immunosuppressive effect. The aims of this study were to examine survival in patients with pancreatic cancer receiving blood transfusion in association with pancreaticoduodenectomy, and to define preoperative risk factors for subsequent transfusion. METHODS: A retrospective review was performed of a prospective database of patients with exocrine tumours of the head of the pancreas who had undergone pancreaticoduodenectomy between 1998 and 2003. Clinical data, transfusion records and preoperative laboratory values were recorded. RESULTS: A total of 294 patients underwent pancreaticoduodenectomy for exocrine tumours in the pancreatic head. Of these, 140 (47.6 per cent) received a blood transfusion. Their median survival was 18 months, compared with 24 months for those who did not have a transfusion (P = 0.036). Postoperative transfusion, margin status and node stage were independent predictors of survival. Age and preoperative total bilirubin and haemoglobin levels were the only preoperative factors that correlated with transfusion. CONCLUSION: In patients with exocrine tumours of the pancreas, blood transfusion should be avoided when possible. Preoperative risk factors can identify patients who are likely to require transfusion and would therefore benefit most from blood conservation methods.


Subject(s)
Blood Loss, Surgical/physiopathology , Erythrocyte Transfusion/mortality , Pancreatic Neoplasms/surgery , Pancreaticoduodenectomy/adverse effects , Postoperative Complications/mortality , Adult , Aged , Aged, 80 and over , Bilirubin/blood , Female , Hemoglobins/analysis , Humans , Male , Middle Aged , Multivariate Analysis , Pancreaticoduodenectomy/mortality , Preoperative Care/methods , Retrospective Studies , Risk Factors , Survival Rate
6.
Lung ; 183(3): 177-83, 2005.
Article in English | MEDLINE | ID: mdl-16078039

ABSTRACT

The aim of this study was to investigate the expression of P-glycoprotein (Pgp), multidrug resistance-related protein-1 (MRP1), and lung resistance-related protein (LRP) in response to chemotherapy in untreated small cell lung cancer (SCLC). Immunohistochemical analyses were performed on multiple nonconsecutive sections of biopsy specimens to detect Pgp, MRP1, and LRP expression in 40 patients with SCLC before chemotherapeutic induction. Response to chemotherapy was evaluated by clinical and radiological methods. The patients were divided into a good response group (n = 20) and a poor response group (n = 20). No significant differences in prognostic factors (Karnofsky performance status, tumor size, or tumor stage) were found between the two groups of patients. The difference in positive Pgp and MRP1 expressions between the good and poor response groups was significant. However, the difference in LRP expression was not significant. We conclude that chemotherapy response of patients with SCLC was related to either Pgp or MRP1 but not LPR expression.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Small Cell/drug therapy , Lung Neoplasms/drug therapy , Multidrug Resistance-Associated Proteins/metabolism , Neoplasm Proteins/metabolism , Vault Ribonucleoprotein Particles/metabolism , Aged , Antineoplastic Agents/administration & dosage , Antineoplastic Agents, Phytogenic/administration & dosage , Biomarkers, Tumor/metabolism , Chi-Square Distribution , Cisplatin/administration & dosage , Drug Resistance, Multiple , Drug Resistance, Neoplasm , Etoposide/administration & dosage , Female , Humans , Immunohistochemistry , Male , Middle Aged , Retrospective Studies , Treatment Outcome
7.
Respiration ; 70(5): 479-83, 2003.
Article in English | MEDLINE | ID: mdl-14665772

ABSTRACT

BACKGROUND: Diffuse infiltrative lung disease (ILD) is a heterogeneous group of disorders which predominantly affect the lung parenchyma and spare the airway. OBJECTIVE: To assess pulmonary vascular endothelium damage in ILD, the lung uptake of technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) was determined. METHODS: In 20 ILD patients and 25 controls without ILD, the lung uptake of 99mTc-HMPAO was measured. Anterior lung imaging, including a large part of the liver, was made 10 min after intravenous injection of 20-25 mCi of 99mTc-HMPAO. Regions of interest covered the liver and lung to calculate the lung/liver uptake ratios. The 20 ILD patients included 10 patients with clinically manifest pulmonary disease (group 1) and 10 asymptomatic patients (group 2). All of the study subjects had normal pulmonary function test results. RESULTS: The mean lung/liver uptake ratio in the 25 controls without ILD (0.36 +/- 0.10) was significantly lower than that in the 20 ILD patients (0.97 +/- 0.61). In addition, the mean lung/liver uptake ratio in the 10 ILD patients with clinically manifest pulmonary disease (1.45 +/- 0.51) was higher than that of the other 10 asymptomatic ILD patients (0.49 +/- 0.09). CONCLUSIONS: Our results indicated that determining the lung/liver uptake ratio on 99mTc-HMPAO lung imaging should be an objective method to assess subclinical pulmonary damage in ILD patients.


Subject(s)
Lung Diseases/diagnostic imaging , Lung/diagnostic imaging , Technetium Tc 99m Exametazime , Adult , Female , Humans , Liver/diagnostic imaging , Middle Aged , Radionuclide Imaging , Radiopharmaceuticals
8.
Neuroscience ; 120(1): 219-26, 2003.
Article in English | MEDLINE | ID: mdl-12849754

ABSTRACT

Recently we demonstrated that a single 3-day episode of carrageenan-induced acute cutaneous inflammation can create a chronic state of increased susceptibility to inflammatory hyperalgesia. In this latent "primed" state, although there is no ongoing hyperalgesia, the hyperalgesic response to subsequent challenges with inflammatory agent (prostaglandin E2; PGE2) is greatly enhanced. Furthermore, the PGE2-induced hyperalgesia in primed skin was found to require activity of the epsilon isozyme of protein kinase C (PKCepsilon), a second messenger that is not required for PGE2-induced hyperalgesia in control animals. In the present study we tested the hypothesis that activity of PKCepsilon not only plays a critical role in the expression of primed PGE2-induced hyperalgesia, but also in the development and maintenance of the primed state itself. Antisense oligodeoxynucleotide was employed to produce a decrease in PKCepsilon in the nerve, verified by Western blot analysis. PKCepsilon was found to be essential both for the development of carrageenan-induced hyperalgesic priming, as well as for the maintenance of the primed state. Furthermore, hyperalgesic priming could be induced by an agonist of PKCepsilon (pseudo-receptor octapeptide for activated PKCepsilon) at a dose that itself causes no hyperalgesia. The finding that transient inhibition of PKCepsilon can not only prevent the development of priming, but can also terminate a fully developed state of priming suggests the possibility that selective targeting PKCepsilon might be an effective new strategy in the treatment of chronic inflammatory pain.


Subject(s)
Gene Expression Regulation, Enzymologic/physiology , Hyperalgesia/enzymology , Intracellular Signaling Peptides and Proteins , Protein Kinase C/antagonists & inhibitors , Protein Kinase C/metabolism , Animals , Carrier Proteins/pharmacology , Carrier Proteins/therapeutic use , Chronic Disease , Dose-Response Relationship, Drug , Gene Expression Regulation, Enzymologic/drug effects , Male , Oligonucleotides, Antisense/pharmacology , Oligonucleotides, Antisense/therapeutic use , Protein Kinase C-epsilon , Rats , Rats, Sprague-Dawley
9.
Respiration ; 70(1): 32-5, 2003.
Article in English | MEDLINE | ID: mdl-12584388

ABSTRACT

BACKGROUND: It was reported that multidrug resistance gene 1 (MDR1) encoding human P-glycoprotein (Pgp) may play an important role in multidrug resistance of lung cancer. Therefore, before initiating chemotherapy, it is important to accurately determine the presence of Pgp in lung cancer, to achieve a satisfactory chemotherapy response. OBJECTIVES: The aim of this study was to compare immunohistochemical analyses of Pgp expression and response to paclitaxel in non-small-cell lung cancer (NSCLC). METHODS: Before chemotherapy with paclitaxel, 50 patients with stage IIIb or IV NSCLC were enrolled in this study. Immunohistochemical analyses were performed on multiple nonconsecutive sections of the biopsy specimens to determine Pgp expression. Chemotherapy response was evaluated in the 3rd month after completion of treatment by clinical and radiological methods. RESULTS: All of the 28 (100%) cases with good response had negative Pgp expression and 15 of the 22 (68%) cases with poor response had positive Pgp expression (p < 0.05). No significant differences were found for other prognostic factors (age, sex, body weight loss, performance status, tumor cell type, and tumor stage) between good response and poor response groups. CONCLUSIONS: Although Pgp expression in NSCLC does not fully predict chemotherapy response to paclitaxel-based therapy, detection of Pgp expression will aid in planning paclitaxel-based therapy for patients with advanced NSCLC. Further studies with a larger number of patients and a longer time of follow-up are necessary to confirm our findings.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Antineoplastic Agents, Phytogenic/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Drug Resistance, Neoplasm , Lung Neoplasms/drug therapy , Paclitaxel/therapeutic use , Adult , Aged , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Female , Humans , Immunohistochemistry , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Male , Middle Aged , Multidrug Resistance-Associated Proteins/metabolism , Neoplasm Staging , Predictive Value of Tests
10.
Lung ; 180(5): 273-9, 2002.
Article in English | MEDLINE | ID: mdl-12489021

ABSTRACT

The purpose of this study was to evaluate the markers' clinical usefulness for early prediction of recurrence, by serial and simultaneous measurements of serum cytokeratin fragment 19 (CYFRA 21-1), before and after surgery on patients with non-small cell lung cancers (NSCLC). The 48 patients enrolled in this study had adenocarcinoma of the lung (adenoCa) (including 24 patients with recurrence and 24 patients without recurrence 1 year after surgery) and 48 patients with squamous cell carcinoma of the lung (SCC) (including 24 cases with recurrence and 24 without recurrence 1 year after surgery). Serial serum levels of CYFRA 21-1 were measured before the operation and 1 week, 1 month, 3 months, 6 months, 9 months, and 12 months after surgery for the early detection of recurrence. The results revealed that (1) the mean serum values of CYFRA 21-1 were significantly higher beginning at 1 month after surgery in the 24 patients with recurrent adenoCa compared with the 24 patients without recurrent adenoCa, (2) mean serum values of CYFRA 21-1 were significantly higher beginning at 1 month after surgery in 24 patients with recurrent SCC when compared with 24 patients without recurrent SCC, and (3) mean serum values of CYFRA 21-1 were significantly higher beginning at 1 month after operation in the total 48 patients with recurrent NSCLC when compared with 48 patients without recurrent NSCLC. We conclude that CYFRA 21-1 is not a good marker for early prediction of NSCLC recurrence including adenoCa and SCC after surgery.


Subject(s)
Adenocarcinoma/blood , Antigens, Neoplasm/blood , Biomarkers, Tumor/blood , Carcinoma, Squamous Cell/blood , Lung Neoplasms/blood , Neoplasm Recurrence, Local/diagnosis , Adenocarcinoma/surgery , Adult , Aged , Carcinoma, Squamous Cell/surgery , Female , Humans , Keratin-19 , Keratins , Lung Neoplasms/surgery , Male , Middle Aged , Predictive Value of Tests , Retrospective Studies
11.
J Neurochem ; 77(1): 336-46, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11279289

ABSTRACT

A synthetic peptide corresponding to the C-terminus of the alpha 3 subunit of the rat neuronal nicotinic acetylcholine receptor (nAChR) was used to generate a rabbit polyclonal alpha 3 antibody. The specificity of this antibody was characterized by immunoblotting, immunohistochemical and immunoprecipitation techniques. Using this antibody, the relative densities of the alpha 3 subunit were quantitatively determined in different brain regions and in superior cervical ganglion (SCG). Among these regions, SCG, interpeduncular nucleus (IPN) and pineal gland showed the highest levels of alpha 3 protein expression. Habenula and superior colliculi had intermediate levels of expression. Low levels were found in cerebral cortex, hippocampus and cerebellum. The ontogenic profile of the alpha 3 subunit in the SCG was also determined. The alpha 3 protein level is low at postnatal day (P 1), but increases rapidly during the first seven postnatal days. This level then plateaus and remains stable through postnatal day 35. These findings suggest that neuronal nAChRs containing the alpha 3 subunit participate in important roles in specific regions of the rat brain and the SCG.


Subject(s)
Brain/metabolism , Neurons/metabolism , Receptors, Nicotinic/biosynthesis , Superior Cervical Ganglion/metabolism , Aging/metabolism , Animals , Antibody Specificity/immunology , Brain/cytology , Cell Line , Female , Habenula/metabolism , Humans , Kidney/cytology , Kidney/metabolism , Mesencephalon/metabolism , Organ Specificity , Pineal Gland/metabolism , Rats , Rats, Sprague-Dawley , Receptors, Nicotinic/analysis , Receptors, Nicotinic/genetics , Receptors, Nicotinic/immunology , Receptors, Nicotinic/metabolism , Superior Cervical Ganglion/cytology , Superior Colliculi/metabolism , Transfection
12.
Am J Pathol ; 156(5): 1693-700, 2000 May.
Article in English | MEDLINE | ID: mdl-10793080

ABSTRACT

Germline mutations in PTEN (MMAC1/TEP1) are found in patients with Cowden syndrome, a familial cancer syndrome which is characterized by a high risk of breast and thyroid neoplasia. Although somatic intragenic PTEN mutations have rarely been found in benign and malignant sporadic thyroid tumors, loss of heterozygosity (LOH) has been reported in up to one fourth of follicular thyroid adenomas (FAs) and carcinomas. In this study, we examined PTEN expression in 139 sporadic nonmedullary thyroid tumors (55 FA, 27 follicular thyroid carcinomas, 35 papillary thyroid carcinomas, and 22 undifferentiated thyroid carcinomas) using immunohistochemistry and correlated this to the results of LOH studies. Normal follicular thyroid cells showed a strong to moderate nuclear or nuclear membrane signal although the cytoplasmic staining was less strong. In FAs the neoplastic nuclei had less intense PTEN staining, although the cytoplasmic PTEN-staining intensity did not differ significantly from that observed in normal follicular cells. In thyroid carcinomas as a group, nuclear PTEN immunostaining was mostly weak in comparison with normal thyroid follicular cells and FAs. The cytoplasmic staining was more intense than the nuclear staining in 35 to 49% of carcinomas, depending on the histological type. Among 81 informative tumors assessed for LOH, there seemed to be an associative trend between decreased nuclear and cytoplasmic staining and 10q23 LOH (P = 0.003, P = 0.008, respectively). These data support a role for PTEN in the pathogenesis of follicular thyroid tumors.


Subject(s)
Cell Nucleus/chemistry , Cytoplasm/chemistry , Neoplasms, Glandular and Epithelial/metabolism , Phosphoric Monoester Hydrolases/analysis , Thyroid Gland/metabolism , Thyroid Neoplasms/metabolism , Tumor Suppressor Proteins , Cell Nucleus/genetics , Cytoplasm/genetics , DNA/analysis , DNA/genetics , Gene Expression Regulation , Humans , Immunohistochemistry , Loss of Heterozygosity , Neoplasms, Glandular and Epithelial/genetics , Neoplasms, Glandular and Epithelial/pathology , PTEN Phosphohydrolase , Phosphoric Monoester Hydrolases/genetics , Thyroid Neoplasms/genetics , Thyroid Neoplasms/pathology
13.
Oncogene ; 19(16): 2060-6, 2000 Apr 13.
Article in English | MEDLINE | ID: mdl-10803467

ABSTRACT

Somatic mutations in mtDNA have recently been identified in colorectal tumours. Studies of oncocytic tumours have led to hypotheses which propose that defects in oxidative phosphorylation may result in a compensatory increase in mitochondrial replication and/or gene expression. Mutational analysis of mtDNA in thyroid neoplasia, which is characterised by increased numbers of mitochondria and is also one of the most common sites of oncocytic tumours. has been limited to date. Using the recently developed technique of two-dimensional gene scanning, we have successfully examined 21 cases of thyroid tumours, six cases of non-neoplastic thyroid pathology, 30 population controls, nine foetal thyroid tissues and nine foetal tissues of non-thyroid origin, either kidney or liver. We have identified three different somatic mutations (23%) in papillary thyroid carcinomas. In addition, we have found significant differential distributions of mtDNA sequence variants between thyroid carcinomas and controls. Interestingly, these variants appear to be more frequent in the genes which encode complex I of the mitochondrial electron transport chain compared to normal population controls. These findings suggest first, that somatic mtDNA mutations may be involved in thyroid tumorigenesis and second, that the accumulation of certain non-somatic variants may be related to tumour progression in the thyroid.


Subject(s)
Carcinoma, Papillary/genetics , DNA, Mitochondrial/genetics , Mutation , Thyroid Neoplasms/genetics , Adenoma/genetics , Case-Control Studies , DNA, Neoplasm/genetics , Genetic Variation , Humans , Molecular Sequence Data , NADH Dehydrogenase/genetics , Thyroid Gland/embryology , Thyroid Gland/pathology
14.
Genes Chromosomes Cancer ; 26(4): 322-8, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10534767

ABSTRACT

Previous studies have demonstrated frequent loss of heterozygosity (LOH) of markers on chromosome arm 10q in both follicular thyroid carcinomas (FTCs) and follicular thyroid adenomas (FAs). A novel tumor suppressor gene, PTEN, has been mapped to 10q23.3 and is the susceptibility gene for Cowden syndrome, an autosomal dominant disorder characterized by multiple hamartomas and a risk of benign and malignant tumors of the breast and thyroid. Studies examining the relationship of somatic PTEN status and follicular thyroid neoplasms have only demonstrated a variable subset of tumors that have somatic monoallelic deletions of PTEN, suggesting that other tumor suppressor genes may be present in this region. We therefore sought to conduct a detailed examination of LOH of 20 polymorphic markers in a 19-cM region spanning 10q22-24, including PTEN, in 44 FAs and 17 FTCs. Using this fine-structure somatic mapping approach, we defined at least two novel regions of LOH in follicular adenomas and follicular carcinomas, suggesting the presence of at least two distinct tumor suppressor genes that may play a role in thyroid neoplasia. Furthermore, the difference in patterns of LOH in adenomas versus carcinomas lends additional support to the hypothesis that adenomas and carcinomas can develop along two separate, nonserial pathways. Genes Chromosomes Cancer 26:322-328, 1999.


Subject(s)
Adenocarcinoma, Follicular/genetics , Adenoma/genetics , Chromosome Deletion , Chromosome Mapping , Chromosomes, Human, Pair 10 , Thyroid Neoplasms/genetics , DNA, Neoplasm/analysis , Genetic Markers , Humans , Loss of Heterozygosity
15.
Appl Opt ; 37(26): 6270-4, 1998 Sep 10.
Article in English | MEDLINE | ID: mdl-18286127

ABSTRACT

We report reliability-test results of transmission-type holographic optical elements (HOE's) made with the DuPont photopolymer HRF-600. The reliability tests performed include 6000 cycles of liquid-to-liquid thermal-shock cycling (-55 degrees C-125 degrees C), 2200 cycles of air-to-air thermal cycling (-55 degrees C-125 degrees C), 1500 h of humidity testing (85 degrees C and a relative humidity of 85%), and 675 h of burn-in testing at 125 degrees C. A total of 210 holograms was tested, with 532 data points collected for diffraction-efficiency measurements. The results show that the average efficiency change after these tests is in the range of -4% to 0% and the standard deviation is only ~10%.

16.
Zhonghua Yi Xue Za Zhi (Taipei) ; 47(1): 18-23, 1991 Jan.
Article in English | MEDLINE | ID: mdl-1848458

ABSTRACT

The experiment of Lithostar, an electromagnetic generator of the second-generation extracorporeal shock wave lithotriptor is presented. From August 2, 1988 to April 4, 1989, 387 treatments in 333 cases were conducted by Lithostar. Among all patients, the overall stone-free rate is 71.9% in which the ureteral stone-free rate (87.7%) is higher than the renal (66.3%) and 19.5% of the patients need additional procedures. This Lithostar proves to be easy in operation, bathless, requires less anesthesia, and may be used in combination with other procedures. It can also make higher average shock number than Dornier HM-3 lithotriptor because of its milder shock wave pressure.


Subject(s)
Lithotripsy/instrumentation , Urinary Calculi/therapy , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Lithotripsy/adverse effects , Male , Middle Aged
17.
Opt Lett ; 13(10): 808-10, 1988 Oct 01.
Article in English | MEDLINE | ID: mdl-19746042

ABSTRACT

Efficient and tunable coherent ultraviolet (360-390 nm) generation in beta-BaB(2)O(4) crystals using type-I phase matching at room temperature is presented. The phase-matching angle is characterized with an alexandrite laser with a wavelength tuning range of 725-785 nm. The crystal angular bandwidth of 0.9 mrad-cm and spectralbandwidth of 1.15 nm-cm are also measured. UV output pulse energy of 105 mJ at 378 nm with 31% energy conversion efficiency is achieved.

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