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J Jo

Publications and source records attributed to J Jo.

At least 19 recordsLinked to original sources
PubMed2001

An Ochrobactrum anthropi gene conferring paraquat resistance to the heterologous host Escherichia coli.

A new gene, pqrA, conferring paraquat resistance to the heterologous host Escherichia coli, from a chromosomal DNA library of Ochrobactrum anthropi JW2, was cloned and analyzed. Cells of E. coli transformed with a plasmid carrying the pqrA gene showed elevated resistance to paraquat, but not to hydrogen peroxide. The predicted amino acid sequence of the PqrA polypeptide showed 71% identity with mll7495 hypothetical membrane protein in Mesorhizobium loti, 49% identity with PA2269 protein in Pseudomonas aeruginosa, and significant identity with other previously reported drug transport proteins. The hydropathy pattern of the PqrA polypeptide showed a significant homology to those of 12-transmembrane-segment (TMS) family export proteins. Immunoblot analysis demonstrated that the PqrA protein found in the membrane protein fraction of O. anthropi JW2 has a molecular mass of 42 kDa. These results suggest that the PqrA protein is a membrane protein that plays an important role in protecting cells against paraquat toxicity.

Amino Acid Sequence↗
PubMed2001

Molecular characterization of cDNA clones for ADP-glucose pyrophosphorylase from Citrus.

Two cDNA clones encoding ADP-glucose pyrophosphorylases have been isolated from fruit and leaf cDNA libraries of Citrus (Citrus unshiu Mac. cv. Miyagawa) in which one was designated as agpS for the small subunit and the other as agpL for the large subunit. Both cDNAs have uninterrupted open reading frames deriving 57-58 kDa polypeptides. The deduced amino acid sequence of agpS has a unique feature. That is, it lacks a cysteine residue (Cys-12) which is usually conserved in all other dicot enzymes. This is the first report of agpS lacking Cys-12 among dicot small subunits. The expression pattern of both subunits showed a different profile in which leaves synthesized both agpS and agpL more vigorously than those of fruits. During leaf development, the transcripts of agpS and agpL showed a higher expression level at younger stages. During fruit development, the expression level of both subunits was observed to be highest in the mini-green stage, but it decreased in the small green stage and it increased again towards the maturing stage. These results suggest that both subunits may play an important role in the regulation of Citrus fruit and leaf development.

Amino Acid Sequence↗
PubMed2001

Collagen type Ialpha1 and vitamin D receptor gene polymorphisms and bone mass in primary biliary cirrhosis.

The potential influence of two gene polymorphisms, vitamin D receptor gene (VDR) and the gene encoding collagen type Ialpha1 (COLIA1) Sp1 polymorphisms, in the reduced bone mass observed in patients with primary biliary cirrhosis (PBC) was assessed in 61 women with PBC (age, 54.1 +/- 1.1 years) by restriction enzyme digestion of polymerase chain reaction (PCR)-amplified DNA extracted from whole blood. Bone mineral density (BMD) of the lumbar spine (L2-L4) and proximal femur were measured by X-ray absorptiometry. The severity of liver disease and cholestasis was also evaluated, and changes in BMD were calculated after a mean period of 2.9 +/- 0.3 years in 41 patients. Sixteen patients (26 %) had the BB, 20 the bb (33 %), and 25 Bb (41%) VDR genotypes. There were no significant baseline BMD differences among the 3 VDR genotypes. Forty-one patients (68%) had the SS, 16 the Ss (27%), and 3 the ss (5%) COLIA1 genotypes. The baseline lumbar BMD was significantly lower in patients having the s allele than in the homozygote SS patients (Z-score, -0.76 +/- 0.24 vs. -0.10 +/- 0.17, P =.02). The severity of cholestasis was not related to the VDR or COLIA1 1 polymorphisms. Lumbar bone loss was independent of VDR and COLIA1 genotypes, but it was associated with cholestasis. In conclusion, the COLIA1 but not VDR polymorphism is a genetic marker of peak bone mass in patients with PBC, although the severity of cholestasis is the main factor for osteoporosis since it is associated with the rate of bone loss.

Bone Density↗
PubMed2000

Expression of the chloroplast-localized small heat shock protein by oxidative stress in rice.

A rice (Oryza sativa L. cv. Nakdong) cDNA clone, Oshsp26, encoding the chloroplast-localized small heat shock protein (smHSP) was isolated. Southern blot analysis of genomic DNA and the result of screening of a cDNA library indicated that the Oshsp26 gene is encoded by a single gene in the rice genome. The Oshsp26 gene was expressed following heat stress: the transcript level was highest when rice leaves were treated at high temperatures for 2h at 42 degrees C, and the transcripts became detectable after 20min and reached a maximum level after 2h. It was also found that the Oshsp26 gene was expressed following oxidative stress even in the absence of heat stress. Treatment of rice plants with methyl viologen (MV) in the light and treatment with hydrogen peroxide (H(2)O(2)), either in the light or in the dark, both caused a significant accumulation of the transcripts and the protein. Since MV treatment in the light leads to the generation of H(2)O(2) inside the chloroplast, it is likely that H(2)O(2) by itself acts to induce the expression of the Oshsp26 gene. These results suggest that the chloroplast smHSP plays an important role in protecting the chloroplast against damage caused by oxidative stress as well as by heat stress.

Amino Acid Sequence↗
PubMed2000

Collagen type Ialpha1 gene polymorphism in idiopathic osteoporosis in men.

OBJECTIVE: To analyse the distribution of polymorphism of the collagen type Ialpha1 gene (COL1A1) and its relationship with bone metabolism and bone turnover in men with idiopathic osteoporosis. METHODS: A total of 35 male patients with idiopathic osteoporosis, aged 50.4 +/- 10.3 yr, and 60 healthy males (controls), aged 47 +/- 17 yr, were included in the study. Serum osteocalcin, 25-hydroxyvitamin D and parathyroid hormone were determined in all patients. The COL1A1 Sp1 genotypes (SS, SS:, ss) were assessed by restriction enzyme digestion (BAL:1) of DNA amplified by the polymerase chain reaction. RESULTS: Patients with idiopathic osteoporosis had a higher frequency of the s allele than men in the control group (29 vs 11%, P: = 0.003) and a higher frequency of the SS: genotype (patients, 48% SS, 46% SS:, 6% ss; controls, 80% SS, 18% SS:, 2% ss; P: = 0.003). No significant differences between genotypes were observed in serum concentrations of osteocalcin, vitamin D or parathyroid hormone among either the patients or the controls. CONCLUSION: This study suggests that, in men with idiopathic osteoporosis, there is a high prevalence of the s allele and the SS: genotype that is unrelated to other parameters of bone metabolism.

Adult↗
PubMed1998

Molecular cloning and characterization of the gene encoding glutathione reductase in Brassica campestris.

We have isolated the Brassica campestris cDNA encoding glutathione reductase of 502 amino acid residues with molecular mass of 54.5 kDa. The deduced amino acid sequences were 92.2%, and 79.5% identical to those of Arabidopsis thaliana, and pea, respectively. As expected, it exhibited a high degree of conservation within the region responsible for the redox reaction and for the binding of GSSG or NADPH. The gene was highly inducible by ozone fumigation or by paraquat treatment.

Amino Acid Sequence↗
PubMed1998

c-erbB-2 oncoprotein, CEA, and CA 15.3 in patients with breast cancer: prognostic value.

The diagnostic value of a new tumor marker, c-erbB-2, was studied in the sera of 50 healthy subjects, 58 patients with benign breast diseases, and 413 patients with breast cancer (186 locoregional, 185 with advanced disease, and 42 with no evidence of disease). Using 15 U/ml as the cut-off, no healthy subjects or patients with benign diseases and only 2.4% of no evidence of disease patients had elevated serum levels. Abnormal c-erbB-2 levels were found in 29% (101/370) of the patients with breast carcinoma (locoregional 9%, metastases 45.4%). CEA (cut-off 5 U/ml) and CA 15.3 (cut-off 35 U/ml) sensitivity was 18% and 16% in patients with locoregional disease and 61% and 70% in those patients with advanced disease, respectively. A trend toward higher serum levels of all three tumor markers in patients with nodal involvement or greater tumor size was found, but was statistically significant only with CEA (p < 0.01). By contrast, c-erbB-2 was related to steroid receptors, in both locoregional and metastatic tumors. When the prognostic value of these markers was evaluated, patients with abnormally high presurgical CEA and c-erbB-2 had a worse prognosis than those patients with normal values, in both node-negative (p < 0.05 and p < 0.001, respectively) and node-positive patients (p < 0.556 and p < 0.001, respectively). By contrast, no relationship was found between CA 15.3 values and prognosis. Multivariate analysis showed that CEA and c-erbB-2 were also prognostic factors. The correlation between serum and tissue levels of c-erbB-2 was studied in the tumors of 161 patients. Significantly higher c-erbB-2 serum levels were found in patients with overexpression in tissue by immunohistochemistry, in both locoregional and advanced disease (p = 0.0001). Serum concentrations in patients with advanced disease were related to the site of recurrence, with significantly higher values in patients with metastases (mainly in those with liver metastases) than in those with locoregional recurrence. In summary, c-erbB-2 serum levels seem to be a useful tumor marker in the prognosis of patients with breast cancer. Using all three tumor markers, sensitivity was 35% in patients with locoregional breast cancer and 88% in patients with recurrence.

Biomarkers, Tumor↗
PubMed1997

Isolation of ALU1-P gene encoding a protein with aluminum tolerance activity from Arthrobacter viscosus.

We isolated a DNA fragment (ALU1-P) encoding a protein with an activity of aluminum tolerance from an Al tolerant soil microorganism, Arthrobacter viscosus. This microorganism was isolated from acidic tea field soils. The cloned DNA is composed of 1090 nucleotides, which has one open-reading frame without any stop codon. However, when the DNA fragment was transferred into Escherichia coli, a microorganism susceptible to Al toxicity, it endowed E. coli with Al tolerance. The deduced amino acid sequence of the DNA showed 65% identity with the protein of YbaX gene in Escherichia coli, and 51.1% identity with YB91 Haein hypothetical protein of HI1191 gene in Haemophilus influenzae. The ALU1-P gene in the expression vector produced a protein of 192 amino acids deriving a molecular weight of 21.3 kDa by using the stop codon in vector. The ALU1-P gene is a new one that has the characteristic of Al tolerance.

Aluminum↗
PubMed1997

Isolation and characterization of a dnaK genomic locus in a halotolerant cyanobacterium Aphanothece halophytica.

We cloned and characterized a genomic locus encoding a distinct member of the DnaK/Hsp70 family of molecular chaperones, dnaK1, from the halotolerant cyanobacterium Aphanothece halophytica. Co-expression of dnaK1 with a plant plastocyanin precursor in Escherichia coli resulted in a dramatic increase in the solubility of the plant protein. This indicates that A. halophytica dnaK1 encodes a functional protein possessing functions assigned to DnaK/Hsp70 chaperone members. The A. halophytica dnaK1 locus also encompasses grpE and dnaJ homologue genes in the order grpE-dnaK1-dnaJ. The transcript content of dnaK1 increased strongly upon subjecting cyanobacterial cells to heat stress. Northern analyses using specific probes indicated transcript species of 2.8, 2.2, 1.3, and 0.7 kb, which comprised grpE-dnaK1, dnaK1, dnaJ, and grpE, respectively. This indicates the presence of different terminators and/or heat stress promoters in this locus. Both dnaK1 transcript and protein levels increased in cyanobacterial cells transferred to hyperosmotic environments, suggesting a role of DnaK1 in the protection and/or recovery of A. halophytica from this particular stress.

Amino Acid Sequence↗
PubMed1997

Serum levels of C-erbB-2 (HER-2/neu) in patients with malignant and non-malignant diseases.

The diagnostic value of a new tumor marker, c-erbB-2, was studied in the sera of 50 controls, 112 patients with benign diseases and 534 patients with malignancies. Using 15 U/ml as the cutoff, no healthy subjects, patients with benign diseases (excluding liver cirrhosis) or patients with no evidence of disease (45 patients) had serum levels higher than this limit. Abnormal c-erbB-2 levels were found in 38.5% (10 of 26) of the patients with liver cirrhosis and in 26.7% (8 of 30) of those patients with primary liver cancer. No differences were found between the c-erbB-2 serum concentrations in liver cirrhosis or primary liver cancer, suggesting the possible catabolism of this antigen in the liver. Abnormal levels of this antigen were found in 20% (56 of 278) of the patients with breast carcinoma (locoregional 7%, metastases 41.5%), in 21% (6 of 28) of ovarian carcinomas (stage I-II 0%, stage III-IV 42.8%), in 21% (3 of 14) of the colorectal tumors (locoregional 0%, metastases 30%), and in 13.3% (11 of 83) of the patients with lung cancer (locoregional 11.5%, metastases 16%). C-erbB-2 sensitivity in other patients with advanced disease was: 25% (9 of 36) in prostatic cancer, 22% (2 of 9) in gastric cancer, and 11% (1 of 9) in vesical tumors. When patients with liver metastases were excluded abnormal c-erbB-2 serum levels were only found in breast, lung, prostatic and ovarian carcinomas. C-erbB-2 sensitivity in patients with lung cancer was related to tumor histology with significantly higher value in non-small cell lung cancer (mainly adenocarcinomas) than in patients with small cell lung cancer (p < 0.013). C-erbB-2 concentrations in patients with breast cancer were significantly higher in patients with recurrence (mainly bone and liver metastases) and in patients with progesterone receptor-negative (< 15 fmol/mg) tumors (p < 0.01). In conclusion, c-erbB-2 is not a specific tumor marker and abnormal serum levels may be found in patients with liver pathologies. Its sensitivity suggests its possible application as a tumor marker in breast, ovarian, lung (mainly adenocarcinomas) and prostatic tumors.

Adult↗
PubMed1996

Prostate-specific antigen detection by ultrasensitive assay in samples from women.

BACKGROUND: The Prostate Specific Antigen (PSA) has been characterized as a specific prostate marker. Recent studies have indicated the existence of a PSA of nonprostatic origin detected in lactating women and breast tumors. METHODS: We have evaluated the presence of PSA by an ultrasensitive assay (COBAS CORE) in 252 serum and non serum samples from women. RESULTS: The results demonstrate the presence of PSA in 100% of the breast secretions, 81% of the breast cysts, 80% of the bronchoalveolar lavage fluids and 71% of the cytosols of breast cancer. Likewise, PSA was detected in 14% of the sera evaluated, although the concentrations were always lower than 0.5 ng/ml. CONCLUSIONS: We conclude that PSA should not continue being considered as the specific prostate tissue marker although, given that the serum concentrations detected are very low, they do appear to interfere to a minimum extent in the usefulness of PSA as a tumor marker.

Breast↗
PubMed1996

Utility of C-erbB-2 in tissue and in serum in the early diagnosis of recurrence in breast cancer patients: comparison with carcinoembryonic antigen and CA 15.3.

To evaluate the utility of c-erbB-2, carcinoembryonic antigen (CEA) and CA 15.3 in the early diagnosis of recurrence, serial serum determinations of these antigens were performed in 200 patients (follow-up 1-4 years, mean 2.2 years) with primary breast cancer and no evidence of residual disease (NED) after radical treatment (radical mastectomy or simple mastectomy and radiotherapy). Eighty-nine patients developed metastases during follow-up. C-erbB-2, CEA and CA 15.3 were elevated (> 20 U ml-1, > 10 ng ml-1 or > 60 U ml-1 respectively) before diagnosis in 28%, 30% and 47% of the 89 patients with recurrence, with a lead time of 4.5 +/- 2.4, 4.9 +/- 2.4 and 4.8 +/- 2.4 months respectively. Tumour marker sensitivity was clearly related to the site of recurrence, with the lowest sensitivity found in locoregional relapse and the highest in patients with liver metastases. When patients with locoregional recurrences were excluded, sensitivity improved: 31% (c-erbB-2), 33% (CEA) and 56% (CA 15.3), with 76% having at least one of the three tumour markers. C-erbB-2 sensitivity in early diagnosis was significantly higher in patients with c-erbB-2 overexpression in tissue (8/10, 80%) than in those without overexpression (1/30, 3.3%) (P = 0.0001). Likewise, higher levels of both, c-erbB-2 and CA 15.3 at diagnosis of recurrence, higher sensitivity in early diagnosis of relapse and a higher lead time were found in PR+ patients (CA 15.3, P < 0.0001) or in PR- patients (c-erbB-2, P = 0.009). Specificity of the tumour markers was 100% for all three markers (111 NED patients). In conclusion, c-erbB-2 is a useful tool for early diagnosis of metastases, mainly in those patients with c-erbB-2 overexpression in tissue. Using all three markers simultaneously it is possible to increase the sensitivity in the early diagnosis of recurrence by 11.2%.

Bone Neoplasms↗
PubMed1996

Prognostic significance of SCC antigen in the serum of patients with head and neck cancer.

SCC antigen (Ag) is a tumor-associated Ag (TAA) obtained from squamous cell carcinoma of the uterine cervix. This study reports the evaluation of this TAA in patients with head and neck malignant diseases and its possible prognostic value. Serum samples from 28 patients with benign head and neck diseases from 399 patients with cancer were obtained prior to treatment. SCC Ag serum levels were determined by radioimmunoassay using 2.5 ng/ml as the upper limit of normality. Elevated SCC Ag serum levels were found in 14% of 28 patients with benign diseases, in 29% of 217 patients with primary tumors, in 48% of 46 patients with recurrence (43% in locoregional, 64% in metastases) and in 4% of 136 patients with no evidence of disease. In patients with primary tumors, SCC Ag serum levels were related to nodal involvement and tumor location with significantly higher levels in node-positive patients (p = 0.001) and in tumors located in the nasopharynx and piriform sinus (p = 0.02). Presurgical SCC Ag serum levels in patients with primary tumors had prognostic value with shorter disease-free survival in those patients with abnormal values of this TAA (p < 0.001), in both, node-negative and node-positive patients (p < 0.01). Multivariate analyses showed that SCC Ag is a significant independent predictor of disease-free survival even when other prognostic factors are considered. In conclusion, pretreatment SCC Ag serum levels are an independent prognostic indicator in patients with head and neck malignancies.

Antigens, Neoplasm↗
PubMed1995

Clinical usefulness of free PSA fraction as an indicator of prostate cancer.

The usefulness of the fPSA fraction in the differential diagnosis of benign prostate hyperplasia (BPH) and prostate cancer was evaluated, with the aim of improving the diagnostic efficacy of PSA. Serum PSA and fPSA determinations were performed by an enzymoimmunoassay technique on an ES-300 system. fPSA constitutes a minor fraction both in normal subjects and in patients with prostate disease, being significantly lower in patients with untreated prostate cancer than in patients with BPH. Likewise, the authors have observed that the sensitivity of the fPSA/PSA ratio has an inversely proportional relationship with the stage of the disease. The results obtained in patients with PSA levels between 4 and 20 micrograms/l are also of note. In this series of patients, the efficacy of the fPSA/PSA ratio was higher than that of PSA, showing a sensitivity of 44% and a specificity of 95% at the cut-off of 0.08.

Biomarkers, Tumor↗
PubMed1995

Use of serial carcinoembryonic antigen and CA 15.3 assays in detecting relapses in breast cancer patients.

UNLABELLED: To evaluate the utility of CEA and CA 15.3 for early diagnosis of recurrence, serial serum determinations of both antigens were performed in 1023 patients (follow-up: 1-10 years, mean 6.2 years) with primary breast cancer (CA 15.3 in 533 cases) and no evidence of residual disease (NED) after radical treatment (radical mastectomy or simple mastectomy and radiotherapy). 246 patients developed metastases during follow-up. RESULTS: CEA and CA 15.3 were elevated ( > 10 ng/ml or > 60 U/ml, respectively) prior to diagnosis in 40% (98/246) and 41% (37/91) of the patients with recurrence, with a lead time of 4.9 +/- 2.2 and 4.2 +/- 2.3 months, respectively. When patients with locoregional recurrences were excluded, sensitivity improved to 46% (CEA) and 54% (CA 15.3), and to 64% with both tumor markers (CEA and/or CA 15.3). Higher levels of both CEA and CA 15.3 at diagnosis of recurrence, higher sensitivity in early diagnosis of relapse, and a higher lead time were found in ER+ (CEA) or PgR+ patients (CA 15.3) than in those that were negative for these receptors in the primary tumor (p < 0.001). Specificity of the tumor markers was 99% for both CEA (777 NED patients) and for CA 15.3 (444 NED patients), respectively. In conclusion, CEA and CA 15.3 are useful tools for early diagnosis of metastases, mainly in those patients with ER+ or PR+ tumors.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1995

Carcinoembryonic antigen in staging and follow-up of patients with solid tumors.

The presence of a tumor antigen in human colonic carcinomas and their metastases was described about 25 years ago. This antigen, called carcinoembryonic antigen (CEA), is one of the first known tumor markers. Since then, many more have been described, but CEA, determined alone or in combination with others, is still one of the most used. CEA is not organ specific and abnormal values may be found in a wide range of carcinomas, especially those with gastrointestinal involvement. CEA assay should not be used for cancer diagnosis because its sensitivity in patients without cancer metastases is low. In addition, abnormal CEA values may be found in patients with benign diseases. However, the probability of malignancy increases directly with CEA concentration. Its main clinical applications are prognosis, early diagnosis of recurrence and follow-up of patients with carcinomas. In a wide range of malignancies, CEA serum levels are clearly related to tumor stage. Presurgical CEA serum levels are a well-established prognostic factor in colorectal, breast and lung cancer. Patients presenting with increased preoperative CEA serum levels have both a shorter disease-free interval and lower survival than those with normal CEA levels. In the early diagnosis of recurrence, CEA also plays an important role: in about 70-85% of patients with colorectal tumors and in 40-50% with breast cancer, CEA serial increase is the first sign of tumor recurrence. In patients with disseminated tumors, serial determinations are also a useful tool for therapy monitoring: CEA values decrease with effective treatment while stable or increasing values are observed when treatment is not effective.

Biomarkers, Tumor↗