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1.
Clin Radiol ; 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-39266374

ABSTRACT

AIMS: To compare the iodine washout rate (IWR) from multiphasic contrast-enhanced computed tomography (CT) with the extracellular volume fraction (fECV) for assessing pancreatic fibrosis and its association with pancreatic cancer. MATERIALS AND METHODS: The study included 51 individuals (33 men; median age: 69 years; 21 with pancreatic cancer, 30 with other diseases) who underwent multiphasic contrast-enhanced CT and histological evaluation for fibrotic changes in pancreas. The histological pancreatic fibrosis fraction (HPFF) was assessed on Azan-stained sections. Pancreatic parenchymal enhancement values were measured to calculate IWR and fECV. Statistical methods, such as Spearman's rho and Mann-Whitney U-test, were used. Linear regression models using IWR and fECV were constructed to predict HPFF, with the performance expressed as root mean squared error (RMSE) and Akaike information criterion (AIC). RESULTS: HPFF correlated with all CT parameters at the estimated transection line, strongest for IWRPPP-EP (r=-0.69, P<0.01). HPFF and fECV values were higher in the pancreatic cancer group than in controls (30% vs. 12.5%, P<0.01; 40.3% vs. 33.0%, P<0.01), whereas IWR values were lower (IWRPPP-EP: 43.3% vs. 55.0%, P<0.01; IWRPVP-EP: 25.0% vs. 33.5%, P<0.01). Linear regression models combining IWRPPP-EP + fECV and IWRPVP-EP + fECV were superior for predicting HPFF, with lower RMSE (9.23-9.35) and AIC (379.38-380.72) values than models with IWR or fECV alone. CONCLUSION: IWRPPP-EP, IWRPVP-EP, and fECV were reliable biomarkers for noninvasively assessing pancreatic fibrosis and were associated with pancreatic cancer risk. Linear regression combining these variables showed enhanced predictive accuracy for pancreatic fibrosis.

2.
Lett Appl Microbiol ; 65(1): 98-104, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28434202

ABSTRACT

To determine the distribution of Norovirus (NoV) genotypes in natural river water in Thailand, we conducted a genome analysis using a next-generation sequencer. Twenty-five river water samples were collected at five different sites of the Khlong Klon River in the suburbs of Bangkok between August 2013 and December 2014. The partial genome of NoV was detected in 15 of the 25 samples (60·0%). Seven of these 15 samples (46·7%) contained multiple NoV GII genotypes: GII.4, GII.6, and GII.17. Our data showed that GII.17 had already emerged in August 2013 as a minor population, and it became a major genotype in December 2014. Our findings indicate that the virus was likely to have been circulating in the community before it appeared in the river water. SIGNIFICANCE AND IMPACT OF THE STUDY: Our study was to investigate the frequencies of multiple genogroups and genotypes of norovirus in the river water near Bangkok, Thailand, by ultra-deep sequencing-based analysis. This study revealed that the epidemic strain was likely to have been circulating in the community before it appeared in the river water. Monitoring of the Norovirus (NoV) genomes in the natural environment may contribute to an understanding of the emergence of new epidemic NoV strains in human populations.


Subject(s)
Caliciviridae Infections/epidemiology , Gastroenteritis/epidemiology , Norovirus/genetics , Rivers/virology , Base Sequence , Caliciviridae Infections/virology , Gastroenteritis/virology , Genome, Viral/genetics , Genotype , High-Throughput Nucleotide Sequencing , Humans , Norovirus/classification , Phylogeny , Thailand/epidemiology
3.
Br J Surg ; 103(1): 97-104, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26506079

ABSTRACT

BACKGROUND: [(18) F]fluorodeoxyglucose (FDG)-PET has been used to evaluate the response of primary tumours to neoadjuvant therapy for oesophageal cancer. The clinical significance of the number of PET-positive nodes before and after therapy has not been investigated previously. METHODS: [(18) F]FDG-PET was performed before and 2-3 weeks after completion of neoadjuvant chemotherapy to identify the number of PET-positive nodes, and these numbers were assessed in relation to metabolic changes in the primary tumour. RESULTS: Of 302 patients in total, 90 had no PET-positive nodes, 83 had one, 59 had two and 70 patients had three or more positive nodes before therapy. After treatment, the numbers were: none in 207 patients, one in 59, two in 20 and three or more in 16 patients. The number of PET-positive nodes after treatment was influenced by both the number of PET-positive nodes before therapy and the response to preoperative therapy, and correlated with the number of metastatic lymph nodes. Overall survival was longer in patients who had no PET-positive nodes after treatment than in those who had one or more. Multivariable analysis identified the numbers of PET-positive nodes before and after chemotherapy as independent prognostic factors, together with clinical response, tumour depth and lymph node involvement. CONCLUSION: The number of PET-positive nodes after treatment correlated with survival in patients with oesophageal cancer who underwent neoadjuvant chemotherapy.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Squamous Cell/drug therapy , Esophageal Neoplasms/drug therapy , Esophagectomy , Lymph Nodes/diagnostic imaging , Positron-Emission Tomography , Adult , Aged , Antineoplastic Agents/administration & dosage , Carcinoma, Squamous Cell/diagnostic imaging , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/surgery , Chemotherapy, Adjuvant , Esophageal Neoplasms/diagnostic imaging , Esophageal Neoplasms/mortality , Esophageal Neoplasms/surgery , Female , Fluorodeoxyglucose F18 , Humans , Lymphatic Metastasis , Male , Middle Aged , Multivariate Analysis , Radiopharmaceuticals , Treatment Outcome
4.
Pharmacogenomics J ; 13(4): 354-8, 2013 Aug.
Article in English | MEDLINE | ID: mdl-22584459

ABSTRACT

Association between response to antidepressant treatment and genetic polymorphisms was examined in two independent Japanese samples of patients with major depressive disorder (MDD). Genome-wide approach using the Illumina Human CNV370-quad Bead Chip was utilized in the analysis of the 92 MDD patients in the first sample. In all, 11 non-intergenic single-nucleotide polymorphisms with uncorrected allelic P-value <0.0001 were selected for the subsequent association analyses in the second sample of 136 MDD patients. Difference in allele distribution between responders and nonresponders were found in the second-stage sample for rs365836 and rs201522 of the CUX1 gene (P=0.005 and 0.004, respectively). The allelic P-values for rs365836 and rs201522 in both samples combined were 0.0000023 and 0.0000040, respectively. Our results provide the first evidence that polymorphisms of the CUX1 gene may be associated with response to antidepressant treatment in Japanese patients with MDD.


Subject(s)
Depressive Disorder, Major/drug therapy , Depressive Disorder, Major/genetics , Genome-Wide Association Study , Homeodomain Proteins/genetics , Nuclear Proteins/genetics , Repressor Proteins/genetics , Adult , Aged , Antidepressive Agents/administration & dosage , Depressive Disorder, Major/pathology , Female , Humans , Japan , Male , Middle Aged , Polymorphism, Single Nucleotide , Transcription Factors
5.
Front Oncol ; 13: 1214977, 2023.
Article in English | MEDLINE | ID: mdl-37483497

ABSTRACT

Objectives: To evaluate whether tumor extracellular volume fraction (fECV) on contrast-enhanced computed tomography (CT) aids in the differentiation between intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC). Methods: In this retrospective study, 113 patients with pathologically confirmed ICC (n = 39) or HCC (n = 74) who had undergone preoperative contrast-enhanced CT were enrolled. Enhancement values of the tumor (Etumor) and aorta (Eaorta) were obtained in the precontrast and equilibrium phase CT images. fECV was calculated using the following equation: fECV [%] = Etumor/Eaorta × (100 - hematocrit [%]). fECV values were compared between the ICC and HCC groups using Welch's t-test. The diagnostic performance of fECV for differentiating ICC and HCC was assessed using receiver-operating characteristic (ROC) analysis. fECV and the CT imaging features of tumors were evaluated by two radiologists. Multivariate logistic regression analysis was performed to identify factors predicting a diagnosis of ICC. Results: Mean fECV was significantly higher in ICCs (43.8% ± 13.2%) than that in HCCs (31.6% ± 9.0%, p < 0.001). The area under the curve for differentiating ICC from HCC was 0.763 when the cutoff value of fECV was 41.5%. The multivariate analysis identified fECV (unit OR: 1.10; 95% CI: 1.01-1.21; p < 0.05), peripheral rim enhancement during the arterial phase (OR: 17.0; 95% CI: 1.29-225; p < 0.05), and absence of washout pattern (OR: 235; 95% CI: 14.03-3933; p < 0.001) as independent CT features for differentiating between the two tumor types. Conclusions: A high value of fECV, peripheral rim enhancement during the arterial phase, and absence of washout pattern were independent factors in the differentiation of ICC from HCC.

6.
Oral Oncol ; 93: 107-113, 2019 06.
Article in English | MEDLINE | ID: mdl-31109690

ABSTRACT

OBJECTIVES: The prognostic value of metabolic tumor volume (MTV) in locally advanced laryngeal or hypopharyngeal cancer is established in the setting of chemoradiotherapy, while it remains unknown in the setting of upfront total laryngectomy. MATERIALS AND METHODS: We retrospectively analyzed 88 patients receiving total laryngectomy and neck dissection, using Cox regression models. RESULTS AND CONCLUSION: Variables related to metastatic lymph node were associated with overall survival, whereas those related to primary tumor were not. In multivariable models, MTV of metastatic lymph nodes (N-MTV) as a continuous variable (Akaike's information criterion (AIC), 277.5) was equivalent to pathological nodal status (AIC, 278.2; P = 0.40), and superior to pathological nodal classification as an ordinal variable (AIC, 281.4; P < 0.05) in ability of predicting death. The risk of death was increased by 1.2-fold (95% confidence interval (CI), 1.0-1.4; P = 0.03) every 10-ml increment of N-MTV, while patients with pN+ disease were at a higher risk of death by 2.9-fold (95% CI, 1.0-12.2; P < 0.05) compared with patients with pN0 disease. Using recursive partitioning analysis (RPA), we classified the patients as having a low, intermediate, or high risk of death on the basis of N-MTV and extranodal extension (ENE). This RPA classification system exhibited greater concordance with overall survival than the classification considering pathological nodal status and ENE (AIC, 275.8 versus 281.4; P = 0.02). In the setting of upfront total laryngectomy, N-MTV is a critical predictor of mortality. A staging system in which N-MTV is incorporated may better inform adjuvant treatment decisions.


Subject(s)
Hypopharyngeal Neoplasms/mortality , Hypopharyngeal Neoplasms/surgery , Laryngeal Neoplasms/mortality , Laryngeal Neoplasms/surgery , Lymphatic Metastasis/pathology , Adult , Aged , Aged, 80 and over , Female , Humans , Hypopharyngeal Neoplasms/pathology , Laryngeal Neoplasms/pathology , Laryngectomy , Male , Middle Aged , Neck Dissection , Neoplasm Staging , Regression Analysis , Retrospective Studies , Survival Analysis , Treatment Outcome , Tumor Burden
7.
Leukemia ; 11 Suppl 3: 26-8, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9209286

ABSTRACT

The mechanisms involved in the restriction of the cellular tropism of HIV-1 to cells of primate origin remain to be clearly defined. However, a number of studies have shown that this is determined not only at the level of the cellular receptor(s) or virus entry, but at a number of additional and later stages in virus replication. We have recently reported that the reverse transcription of HIV-1 RNA is markedly enhanced by the association of the gag encoded nucleocapsid p15 protein and cellular topoisomerase 1. In the present study we have now investigated if the recruitment of cellular topoisomerase I during virus replication is important in determining the cellular tropism of HIV-1. Employing a stable murine cell line, L929, expressing both human CD4 and topoisomerase I, it could be demonstrated that effective proviral DNA synthesis occurred following infection. In contrast in cells expressing only human CD4 proviral DNA synthesis was not detected. In addition we have co-expressed fusin, a protein known to act as an accessory factor as the virus entry stage in infection of T cell tropic HIV-1, to support viral entry completely. However no progeny virus could be detected after HIV-1 infection. These results suggest that reverse transcription in vivo is critically dependent on the presence of cellular topoisomerase I, and support the view that involvement of this enzyme is in HIV-1 replication. Moreover the findings suggest that other factors which remained to be identified, are involved in restricting HIV-1 replication in non-primate cells.


Subject(s)
DNA Topoisomerases, Type I/metabolism , Gene Products, gag/biosynthesis , HIV-1/physiology , RNA, Viral/biosynthesis , Virus Replication , Animals , Antigens, CD/biosynthesis , CD4 Antigens/biosynthesis , Cell Line , DNA Replication/drug effects , Genes, gag , Glutathione Transferase , HIV-1/genetics , Humans , Mice , Polymerase Chain Reaction , Primates , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/metabolism , Transfection , Zidovudine/pharmacology
8.
Leukemia ; 11 Suppl 3: 113-5, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9209315

ABSTRACT

The mechanisms involved in the restriction of the cellular tropism of HIV-1 to cells of primate origin remain to be clearly defined. However, a number of studies have shown that this is determined not only at the level of the cellular receptor(s) or virus entry, but at a number of additional and later stages in virus replication. We have recently reported that the reverse transcription of HIV-1 RNA is markedly enhanced by the association of the gag encoded nucleocapsid p15 protein and cellular topoisomerase I. In the present study we have investigated if the recruitment of cellular topoisomerase I during virus replication is important in determining the cellular tropism of HIV-1. Employing a stable murine cell line, L929, expressing both human CD4 and topoisomerase I, it could be demonstrated that effective proviral DNA synthesis occurred following infection. In contrast in cells expressing only human CD4, proviral DNA synthesis was not detected. In addition we have co-expressed fusin, a protein known to act as an accessory factor as the virus entry stage in infection of T cell tropic HIV-1, to support viral entry completely. However no progeny virus could be detected after HIV-1 infection. These results suggest that reverse transcription in vivo is critically dependent on the presence of cellular topoisomerase I, and support the view that involvement of this enzyme is important in HIV-1 replication. Moreover the findings suggest that other factors which remained to be identified, are involved in restricting HIV-1 replication in non-primate cells.


Subject(s)
DNA Topoisomerases, Type I/metabolism , HIV-1/physiology , Virus Replication , Animals , Antigens, CD/biosynthesis , CD4 Antigens/biosynthesis , Cell Line , DNA Topoisomerases, Type I/biosynthesis , Genes, gag , Humans , Mice , Nucleocapsid/biosynthesis , Primates , RNA, Viral/biosynthesis , Recombinant Proteins/biosynthesis , Transfection
9.
J Cereb Blood Flow Metab ; 15(2): 235-41, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7860657

ABSTRACT

To determine acute postischemic metabolic changes of the ischemic rim under conditions of poor collateral circulation, we examined cerebral blood flow and glucose metabolism in the area of the brain around the ischemic tissue in 36 male spontaneously hypertensive stroke-prone rats (SHRSP) in the acute stage of focal ischemia. The right middle cerebral artery (MCA) was occluded dorsal to the rhinal fissure. Four hours after occlusion, local cerebral blood flow (LCBF), glucose content (LCGC), and glucose utilization (LCGU) were measured by quantitative autoradiographic techniques. The lumped constant was determined from the corresponding LCGC. LCBF showed a widespread and marked decrease in the cortex surrounding the ischemic core, in the thalamus, and in the medial portion of the striatum in the MCA-occluded hemisphere, while the lateral segment of the striatum showed an increase of 36%, compared with findings on the contralateral side. LCGC showed little regional variation, but there was an increase of 38% in the zone bordering the ischemic area. LCGU at the cortex surrounding the ischemic core and in the external capsule showed an increase of 55%. The cortex surrounding the ischemic core, the thalamus, and the lateral segment of the striatum in the MCA-occluded hemisphere showed significant decreases in LCGU. It has been speculated that a high accumulation of glucose reflects a demand for glucose for anaerobic glycolysis in the border areas and that such a demand is probably greater in cases of impaired oxygen delivery due to the presence of microcirculatory disturbances in the MCA-occluded SHRSP.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Brain Ischemia/metabolism , Brain Ischemia/physiopathology , Cerebrovascular Circulation , Glucose/metabolism , Animals , Cerebral Arteries/physiopathology , Male , Rats , Rats, Inbred SHR
10.
Gene ; 99(2): 261-5, 1991 Mar 15.
Article in English | MEDLINE | ID: mdl-1673667

ABSTRACT

Vectors derived from the Escherichia coli filamentous phage, fd-tet, expressing parts of the human immunodeficiency virus (HIV) gag genes were constructed and analyzed. The immunoreactive domain of HIV Gag antigens was produced in the form of a fusion protein, with a phage minor coat protein, called protein III, playing an important role in phage infectivity. A micropanning procedure, utilizing the strong affinity of biotinylated antibody to streptavidin, was applied for the selection of clones. A simple preparation procedure consisting of polyethyleneglycol precipitation of the recombinant phage from the E. coli supernatant allowed us to detect HIV antigens by enzyme-linked immunosorbent assay (ELISA). Cloned FUSE-gag, as isolated using anti-Gag RL4.72.1 monoclonal antibody (mAb), contained a nucleotide sequence coding for 91 amino acids of HIV Gag p24. It specifically reacted with the mAb in the ELISA. Construction of the mAb-selectable phages permitted localization of epitopes for mAb. Infectivity of the phage clone was specifically neutralized by the anti-HIV mAb. Immunoelectroblotting analysis of recombinant phages revealed the presence of an about 65-kDa band reacting with anti-HIV mAb. This Mr corresponded to the size of the fused form of the FUSE 1 protein III. Human sera from HIV-infected and uninfected individuals reacted with recombinant protein III, as well as the original form of protein III.


Subject(s)
Escherichia coli/genetics , Gene Products, gag/immunology , HIV/genetics , Viral Fusion Proteins/immunology , Amino Acid Sequence , Base Sequence , Blotting, Western , Cloning, Molecular , Enzyme-Linked Immunosorbent Assay , Gene Products, gag/biosynthesis , Genes, gag , Genetic Vectors , HIV/immunology , Molecular Sequence Data , Polymorphism, Restriction Fragment Length , Viral Fusion Proteins/biosynthesis
11.
Am J Psychiatry ; 156(5): 774-6, 1999 May.
Article in English | MEDLINE | ID: mdl-10327914

ABSTRACT

OBJECTIVE: Tryptophan hydroxylase is the rate-limiting enzyme in the biosynthesis of serotonin. The authors examined whether polymorphisms A218C and A779C in intron 7 of the tryptophan hydroxylase gene are associated with a risk for affective disorders or suicidal behavior. METHOD: Subjects were 141 patients with bipolar disorder and 73 patients with unipolar affective disorder, 46 of whom had a history of attempted suicide, and 208 healthy volunteers. All subjects were unrelated to each other, and all were Japanese. Genotyping was performed by polymerase chain reaction amplification followed by digestion by a restriction enzyme and single-strand conformational polymorphism analysis. RESULTS: There was no significant genotypic or allelic association of the A218C polymorphism with bipolar disorder, unipolar depression, or history of attempted suicide. In nearly 100% of the subjects, genotypes for the A779C were identical to those for the A218C. CONCLUSIONS: The authors conclude that the examined polymorphisms are unlikely to have major relevance to the pathogenesis of affective disorders or suicidal behavior.


Subject(s)
Asian People/genetics , Depressive Disorder/genetics , Polymorphism, Genetic , Suicide, Attempted/statistics & numerical data , Tryptophan Hydroxylase/genetics , Adult , Alleles , Bipolar Disorder/genetics , Female , Genotype , Humans , Introns/genetics , Japan/epidemiology , Male , Middle Aged , Polymerase Chain Reaction
12.
FEBS Lett ; 426(3): 367-72, 1998 Apr 24.
Article in English | MEDLINE | ID: mdl-9600268

ABSTRACT

The V3 region of HIV-1 envelope protein possesses a single N-linked sugar chain, which is conserved in most HIV-1 strains. We studied its role in the life cycle of HIV-1 strains with different co-receptor usage. Removal of the glycan appeared to cause a marked reduction of CXCR-4- but not CCR-5-dependent virus entry. A basic amino acid substitution at the 11th position of V3 markedly compensated for the removal of the N-glycan. These results indicate that the N-glycan plays an important role for CXCR-4-dependent virus entry and that this role is exerted in a particular context of the peptide backbone.


Subject(s)
Giant Cells/virology , HIV Envelope Protein gp120/metabolism , HIV-1/metabolism , Peptide Fragments/metabolism , Polysaccharides/physiology , Receptors, CCR5/physiology , Receptors, CXCR4/physiology , Amino Acid Sequence , Amino Acid Substitution , Cell Line, Transformed , Glycosylation , HIV Envelope Protein gp120/genetics , HIV-1/isolation & purification , HIV-1/physiology , Humans , Molecular Sequence Data , Mutagenesis, Site-Directed , Peptide Fragments/genetics , Receptors, HIV/physiology , Virus Replication
13.
Cancer Gene Ther ; 6(5): 423-7, 1999.
Article in English | MEDLINE | ID: mdl-10505852

ABSTRACT

Epidermal growth factor receptor (EGFR) protein overexpression is commonly found in human gastric cancer, and its gene amplification is known to correlate with poor prognosis in gastric cancer patients. With regard to therapy trials targeting EGFR, it has been reported that stable transfection of EGFR antisense or treatment with antibody against EGFR results in growth suppression of human cancer cells that express high levels of EGFR. We have designed an adenovirus-expressing antisense EGFR and have investigated its effect on the growth of gastric cancer in vitro and in vivo. Following infection with EGFR antisense RNA-expressing adenovirus (Ad-EAS), the cell surface EGFR protein levels of infected cancer cells were markedly reduced, and the in vitro growth of Ad-EAS-infected cells was significantly inhibited relative to control-infected cells in all three gastric cancer cell lines (AGS, KKLS, and MKN28) studied here (P < .0002). In a nude mouse subcutaneous tumor system, in vivo tumor growth of MKN28 was significantly inhibited after Ad-EAS treatment, and inhibition on day 48 was 93% by volume compared with that of untreated controls. These results suggest that an adenoviral vector system targeting the down-regulation of EGFR could be a good candidate for the therapy of gastric cancers that overexpress EGFR.


Subject(s)
Adenoviridae/genetics , ErbB Receptors/genetics , Genetic Vectors , RNA, Antisense/pharmacology , Stomach Neoplasms/pathology , Animals , Cell Division/genetics , Humans , Mice , RNA, Antisense/administration & dosage , Tumor Cells, Cultured
14.
Clin Exp Metastasis ; 16(8): 743-50, 1998 Nov.
Article in English | MEDLINE | ID: mdl-10211987

ABSTRACT

The expression of the sialyl Lewis x antigen (sLe(x)) on surgical specimens of primary gastric cancer correlates with the degree of differentiation and synchronous and metachronous liver metastasis. Multivariate analysis by means of Quantification theory II revealed that sLe(x) expression was an independent risk factor for liver metastasis from gastric cancer.


Subject(s)
Antigens, Tumor-Associated, Carbohydrate/biosynthesis , Biomarkers, Tumor/biosynthesis , Gangliosides/biosynthesis , Liver Neoplasms/metabolism , Liver Neoplasms/secondary , Oligosaccharides/biosynthesis , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathology , Aged , Animals , CA-19-9 Antigen , Female , Gastric Mucosa/metabolism , Humans , Immunohistochemistry , Liver Neoplasms/pathology , Male , Middle Aged , Multivariate Analysis , Prognosis , Risk Factors , Sialyl Lewis X Antigen
15.
J Nucl Med ; 40(6): 1003-8, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10452318

ABSTRACT

UNLABELLED: Dual-head coincidence gamma camera 18F-fluorodeoxyglucose (FDG) imaging was compared with FDG PET in the detection of breast cancer and axillary lymph node metastasis. METHODS: Both coincidence gamma camera FDG imaging and FDG PET were performed in a cylindrical phantom containing spheres of different sizes and activity ratios (5:1, 10:1 and 15:1) and in 30 women (age range 32-78 y) with suspected breast cancer. Biopsies or mastectomies were performed in all patients. Images were visually assessed, and the count ratio between tumor and normal tissue (T/N ratio) was calculated. RESULTS: In the phantom studies, coincidence gamma camera imaging visualized the smallest sphere (1.0 cm) at a ratio of 15:1 but not at ratios of 5:1 and 10:1. Coincidence gamma camera imaging visualized the other spheres (> or =1.3 cm) at all ratios. PET visualized all spheres at all ratios. In the clinical studies, 22 of 26 breast carcinomas detected by PET were also detected by coincidence gamma camera imaging.. Coincidence gamma camera imaging detected all of the carcinomas > or =2 cm in diameter (n = 10) and 12 of 16 carcinomas <2 cm. In breast carcinomas detected by both PET and coincidence gamma camera imaging, the T/N ratio in non-attenuation-corrected PET (7.12 +/- 7.13) was significantly higher than in coincidence gamma camera imaging (2.90 +/- 1.47, P < 0.005). Four of 8 axillary lymph node metastases detected by PET were detected by coincidence gamma camera imaging. Of 9 axillary lymph node metastases <1.0 cm in diameter, 7 and 3 were detected by PET and coincidence gamma camera imaging, respectively. CONCLUSION: Coincidence gamma camera imaging is useful in detecting breast carcinoma > or =2 cm in diameter but is not reliable for breast carcinoma <2 cm in diameter. Coincidence gamma camera imaging may be useless or even dangerous in the detection of axillary lymph node metastasis.


Subject(s)
Breast Neoplasms/diagnostic imaging , Carcinoma, Ductal, Breast/diagnostic imaging , Carcinoma, Lobular/diagnostic imaging , Carcinoma, Medullary/diagnostic imaging , Fluorodeoxyglucose F18 , Gamma Cameras , Lymphatic Metastasis/diagnostic imaging , Radiopharmaceuticals , Tomography, Emission-Computed , Adult , Aged , Axilla , Female , Humans , Middle Aged , Phantoms, Imaging
16.
J Nucl Med ; 40(5): 854-61, 1999 May.
Article in English | MEDLINE | ID: mdl-10319761

ABSTRACT

UNLABELLED: To elucidate the applicability of 99mTc-HL91 (HL91) a putative hypoxic tracer, to the imaging of hypoxia in tumors, a biodistribution study of the tracer was performed. The intratumoral distribution of HL91 was compared with that of 14C-deoxyglucose (DG) and the expression of glucose transporter 1 (GLUT1) in an implanted tumor. METHODS: Biodistribution of HL91 after intravenous injection into Wistar rats with rat mammary tumor (Walker-256) was studied by determining blood and tissue levels of radioactivity from 15 min to 6 h after injection. Dual ex vivo autoradiography was performed on sections of the tumor using HL91 (74 MBq) and DG (185 kBq). The same sections were immunohistologically analyzed with anti-GLUT1 antibody. Tumor tissue was histologically divided into areas of viable cancer cells, necrosis and granulation tissue. The viable cancer cell area was further divided into normoxic and hypoxic areas. Uptake of both tracers in each area was measured quantitatively. The intensity of GLUT1 staining (relative optical density [ROD]) in each area was evaluated by densitometry. RESULTS: The uptake of HL91 in the tumor reached a maximal value (0.897 +/- 0.118% ID [injected dose], mean +/- SD, n = 5) at 120 min after intravenous injection of HL91, then gradually decreased. The tumor-to-muscle ratio continued to increase until 360 min (4.34 at 120 min, 7.01 at 240 min and 10.4 at 360 min). HL91 accumulated to significantly higher levels in the hypoxic area than those in the other tissues (P < 0.0001). Uptake of DG and expression of GLUT1 were significantly higher in the hypoxic area than in the normoxic area (P < 0.0001). In the viable cancer cell area, uptake of HL91 and expression of GLUT1 were strongly correlated (r = 0.624-0.868, mean r = 0.743, P < 0.0001), and DG uptake was moderately correlated with GLUT1 expression (r = 0.328-0.669, mean r = 0.505, P < 0.0001). CONCLUSION: These results indicate that HL91 can be used to detect tumor hypoxia.


Subject(s)
Carcinoma 256, Walker/diagnostic imaging , Mammary Neoplasms, Experimental/diagnostic imaging , Organotechnetium Compounds , Oximes , Radiopharmaceuticals , Animals , Carbon Radioisotopes , Deoxyglucose , Female , Monosaccharide Transport Proteins/metabolism , Radionuclide Imaging , Rats , Rats, Wistar , Tissue Distribution
17.
J Nucl Med ; 42(4): 601-8, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11337549

ABSTRACT

UNLABELLED: PET with a double-head gamma camera (hybrid PET) is a new approach to tumor imaging with 18F-FDG. This study was conducted to clarify the feasibility of whole-body FDG hybrid PET in the staging of non-Hodgkin's lymphoma (NHL) in comparison with PET with a dedicated camera (dedicated PET) and to compare the results of both FDG studies with those of CT and 67Ga scanning as conventional imaging studies (CIS). METHODS: Thirty patients with NHL were prospectively evaluated. The results of the imaging studies regarding detection of the sites involved and staging were compared with each other and with those of the reference standard based on the final overall clinical evaluation. RESULTS: Of the total of 206 sites, whole-body FDG hybrid PET and dedicated PET detected 159 sites (77.2%) and 179 sites (86.9%), respectively. Eighteen of the 20 sites missed by hybrid PET alone consisted of lesions < 1.5 cm. Both FDG studies provided concordant staging results in all but 2 patients. CIS, on the other hand, detected 164 (79.6%) of the 206 sites, 137 of which were also detected by hybrid PET. Hybrid PET detected an additional 22 sites not found by CIS, whereas CIS detected 27 additional sites. Hybrid PET and CIS provided concordant staging results in 19 patients. Hybrid PET correctly staged NHL in 5 additional patients, whereas CIS correctly staged NHL in only 1 additional patient. CONCLUSION: Whole-body FDG hybrid PET appeared to be an accurate method of staging NHL. Despite its poorer image quality compared with dedicated PET, hybrid PET provided NHL staging results comparable with those of dedicated PET. Hybrid PET also yielded results comparable with those of CIS. However, whole-body FDG hybrid PET is currently inadequate as a single modality for staging NHL and is complementary to CT.


Subject(s)
Fluorodeoxyglucose F18 , Lymphoma, Non-Hodgkin/diagnostic imaging , Radiopharmaceuticals , Tomography, Emission-Computed , Adolescent , Adult , Aged , Aged, 80 and over , Feasibility Studies , Female , Gallium Radioisotopes , Gamma Cameras , Humans , Lymph Nodes/diagnostic imaging , Lymphatic Metastasis , Lymphoma, Non-Hodgkin/pathology , Male , Middle Aged , Neoplasm Staging , Prospective Studies , Tomography, Emission-Computed/instrumentation , Tomography, X-Ray Computed
18.
J Nucl Med ; 40(4): 566-73, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10210214

ABSTRACT

UNLABELLED: The purpose of this study was to elucidate the feasibility of fluorodeoxyglucose gamma camera coincidence imaging (FDG GCI) in the evaluation of lung cancer in comparison with FDG PET. METHODS: Twenty-three patients with recently diagnosed lung cancer were examined with both FDG PET and FDG GCI on the same day. Pulmonary lesions were analyzed visually and semiquantitatively using the ratio of lesion-to-background counts (L/B ratio). The L/B ratio of FDG PET without attenuation correction (AC) was also calculated and compared. Nodal stations were only visually analyzed. RESULTS: FDG GCI and FDG PET could detect 22 and 23, respectively, of 23 pulmonary lesions by visual analysis (95.7% versus 100%). The L/B ratio of FDG GCI was 4.26 +/- 2.55, and significantly lower than that of FDG PET (9.29 +/- 4.95; P < 0.01). The L/B ratio of FDG PET was significantly higher with AC than that without AC (9.29 +/- 4.95 vs. 6.66 +/- 4.65; P < 0.01). When the L/B ratio threshold was set at 5.0 for FDG PET and 2.7 for FDG GCI, their sensitivity was 87.0% and 73.9%, respectively. Of the 3 and 6 patients with false-negative results on semiquantitative analysis, the lesions in 3 patients on FDG PET and 4 patients on FDG GCI were less than or equal to 2.0 cm in greatest diameter, respectively. In the assessment of mediastinal involvement, FDG PET was 77.8% sensitive, 78.6% specific and 78.3% accurate, whereas FDG GCI was 77.8% sensitive, 92.9% specific and 87.0% accurate. In the hilar regions, FDG PET was 100% sensitive, 84.2% specific and 87.0% accurate, whereas FDG GCI was 75.0% sensitive, 89.5% specific and 87.0% accurate. CONCLUSION: In this study, FDG GCI yielded results comparable to FDG PET on visual analysis to detect pulmonary lesions and lymph node metastases. However, the lesion-to-background contrasts of pulmonary lesions and nodal involvement were lower in FDG GCI than in FDG PET. Comparison between the L/B ratio of FDG PET with and without AC indicated that, with AC, FDG GCI would be closer to FDG PET in the evaluation of lung cancer.


Subject(s)
Fluorodeoxyglucose F18 , Gamma Cameras , Lung Neoplasms/diagnostic imaging , Tomography, Emission-Computed , Adenocarcinoma/diagnostic imaging , Carcinoma, Squamous Cell/diagnostic imaging , Feasibility Studies , Female , Fluorine Radioisotopes , Humans , Image Processing, Computer-Assisted , Lymphatic Metastasis , Male , Middle Aged , Radiopharmaceuticals , Sensitivity and Specificity
19.
AIDS Res Hum Retroviruses ; 17(11): 1083-7, 2001 Jul 20.
Article in English | MEDLINE | ID: mdl-11485626

ABSTRACT

We constructed an infectious DNA clone of the HIV-1 A/G recombinant 97GH-AG2, which was isolated in Ghana in 1997 and was classified originally as subtype A. By phylogenetic and recombination breakpoint analyses, p97GH-AG2 was grouped in the circulating form of A/G recombinants (CRF02_AG) and was found to contain the least amount of subtype G-derived region among the known CRF02_AG HIV-1 DNAs. This result suggests that CRF02_AG may be a predominant form in Ghana. Virions produced by transfection of p97GH-AG2 into 293T cells grew in phytohemagglutinin-stimulated peripheral blood mononuclear cells (PBMCs). 97GH-AG2 also replicated efficiently in CCR5-expressing HeLa cells, MAGIC5, but only weakly in the parent MAGI cells, indicating that 97GH-AG2 uses mostly CCR5 as a coreceptor. Isolation of the first HIV-1 (CRF02_AG) DNA clone that replicates in PBMCs will accelerate the molecular analysis of this subtype.


Subject(s)
HIV Infections/genetics , HIV-1/genetics , Adult , Cloning, Molecular , DNA, Recombinant/genetics , DNA, Recombinant/isolation & purification , HIV Infections/transmission , HIV Infections/virology , Humans , Leukocytes, Mononuclear/virology , Male , Molecular Sequence Data , Phylogeny , Sequence Analysis, DNA , Transfection , Tumor Cells, Cultured , Virus Replication
20.
AIDS Res Hum Retroviruses ; 17(7): 649-55, 2001 May 01.
Article in English | MEDLINE | ID: mdl-11375062

ABSTRACT

We have isolated a replication-competent, full-length molecular clone of HIV-1 CRF02_AG, designated p97GH-AG1, by reconstituting two separately amplified genomic regions of an HIV-1 provirus of a 1997 Ghanaian isolate. The phylogenetic and recombination breakpoint analyses revealed that 97GH-AG1 had an A/G recombinant structure similar to that of prototype Nigerian isolate IbNG. The 17-nucleotide insertion downstream of the primer-binding site appeared to be a common sequence signature specific to most CRF02_AG strains, including 97GH-AG1. 97GH-AG1 showed an R5 phenotype and exerted productive infection in both HOS and NP2 cell infectivity assays, whereas it failed to show a detectable level of progeny production in peripheral blood mononuclear cells (PBMCs). The data may suggest the presence of unknown determinant(s) that dictate efficient replication in PBMCs, but that are not required for replication in immortalized cell lines.


Subject(s)
HIV Seropositivity/virology , HIV-1/classification , HIV-1/genetics , Phylogeny , Recombination, Genetic , Virus Replication , Amino Acid Sequence , Base Sequence , DNA, Viral , Female , Ghana , Humans , Middle Aged , Molecular Sequence Data , Nucleotide Mapping , Polymerase Chain Reaction
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