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J Mora

Publications and source records attributed to J Mora.

At least 73 records · Page 4Linked to original sources
PubMed1999

[The efficacy of the radioiodine treatment of toxic thyroid adenoma and multinodular goiter].

OBJECTIVE: To investigate the effect of radioiodine therapy of thyroid adenoma (TA) and toxic multinodular goitre (TMG) on function and thyroid volume. MATERIALS AND METHODS: Prospective study which includes 14 consecutive patients with TA and 15 with TMG treated with radioiodine and followed for two years. The therapeutic dose was fixed at 15 mCi for TA and 150 microCi x g of thyroid tissue/uptakes at 6 h (mean dose: 14.4 +/- 4.1 mCi) for TMG. Thyroid function and echographic thyroid volume were determined before and at 1, 3, 6, 12 and 24 months. RESULTS: 90% of patients with TA and 80% with TMG recovered euthyroidism at the third month. One patient with TA and three with TMG required two doses. The latter patients were the only ones with hypothyroidism at two years. The TA volume decreased from 20 +/- 8.5 ml to 10.4 +/- 8.1 ml at two years (p = 0.004). The extranodular thyroid volume did not change (initial: 16.4 +/- 10.4 ml versus 15.6 +/- 3.8 ml at the second year). The thyroid volume in TMG decreased from 66.5 +/- 28 ml to 39.8 +/- 13.5 ml at two years (p = 0.006). The largest reductions for TA and TMG were 54% and 38%, respectively, within the first six months. Only one patient with TA and another patient with TMG had their volumes transiently increased, lower than 10%. CONCLUSIONS: Therapy with radioiodine of TA and TMG achieves a rapid recovery of euthyroidism and a gradual decrease in thyroid volume with a low incidence of hypothyroidism, with no additional secondary effects. It has proved to be a valid alternative to surgical therapy.

Adenoma↗
PubMed1998

Listeriosis in pediatric oncology patients.

BACKGROUND: Adult cancer patients are considered to be at an increased risk for Listeria monocytogenes infections, but, to the authors' knowledge, little information regarding this infection in the pediatric oncology population has been published. METHODS: The Memorial Sloan-Kettering Cancer Center microbiology laboratory's database was searched for cases of Listeria monocytogenes infection during the period from January 1981 to December 1996, and thorough chart reviews of the cases identified in patients age < 21 years were performed. RESULTS: Listerial infections occurred in 5 children (3 with leukemia, 1 with lymphoma, and 1 with a brain tumor) among 20,612 admissions to the pediatric department during this period. All five children were actively receiving therapy for their malignancy, and two also were receiving other potentially immunosuppressive therapies. None was receiving co-trimoxazole prophylaxis. All were treated successfully for the Listeria monocytogenes infection with ampicillin and gentamicin (four patients) or ampicillin alone (one patient). At last follow-up two patients were long term, event-free survivors, two had died of their underlying malignancy, and one patient had died of cytomegalovirus pneumonitis. CONCLUSIONS: Listeria monocytogenes infections in pediatric oncology patients can be treated successfully with ampicillin-containing antibiotic regimens.

Adolescent↗
PubMed1998

Use of somatostatin analogue scintigraphy in the localization of recurrent medullary thyroid carcinoma.

Detection of recurrence of medullary thyroid carcinoma (MTC) remains a diagnostic problem. Increased serum tumour marker levels frequently indicate recurrence while conventional imaging techniques (CIT) are non-diagnostic. In this study, we performed indium-111 octreotide scintigraphy and CIT in a series of 20 patients with MTC presenting with elevated serum tumour markers after surgery. 111In-octreotide whole-body studies detected 15 pathological uptake foci in 11 of the 20 patients studied and CIT detected 17 lesions in 11 of the 20 patients. Ten patients underwent reoperation, five of them with positive 111In-octreotide scintigraphy and CIT and two with positive isotopic exploration and negative CIT. Surgical findings demonstrated that the results of isotopic study and CIT had been false-positive for MTC in one case (sarcoidosis). The six patients with true-positive 111In-octreotide studies had significantly higher basal calcitonin (CT) and carcinoembryonic antigen (CEA) levels than the patients with negative isotopic studies. The expression of somatostatin receptor (SSTR) subtypes by PC-PCR could be investigated in four cases with a positive isotopic study. Among the three cases with a true-positive study, SSTR2, the SSTR subtype that preferentially binds to the somatostatin analogue octreotide, was detected in two, SSTR5 was demonstrated in the three, and SSTR3 was detected in one. No subtype of SSTR was detected in the case with a final diagnosis of sarcoidosis. We conclude that 111In-octreotide has limited sensitivity in detecting recurrence in patients with MTC, although its sensitivity may improve with high serum CT levels. This radionuclide imaging technique should be employed when conventional imaging techniques are negative or inconclusive or when the presence of somatostatin receptors may provide the basis for treatment with somatostatin analogues.

Adult↗
PubMed1998

Tolerate, engage or withdraw: a study of the structure of families coping with alcohol and drug problems in south west England and Mexico City.

AIMS: To explore the structure underlying individual differences in the ways family members cope with drinking or drug problems. DESIGN: Cross-sectional interview and questionnaire study of a series of family members in two contrasting socio-cultural groups. SETTING: Mexico City and South West England. PARTICIPANTS: Two hundred and seven family members from separate families, three-quarters women, one-quarter men, mostly partners or parents. DATA: Long semi-structured interviews; the Coping Questionnaire (CQ). FINDINGS: Factor and subscale analyses of the CQ data and textual analysis of the interview reports were used to test the hypothesis that the underlying structure to coping could be described in terms of eight or nine coherent and distinct ways of coping. Neither form of analysis gave strong support to this hypothesis. CONCLUSIONS: It is concluded that the structure of coping can best be described in terms of three broad coping positions: tolerating, engaging and withdrawing. These conclusions challenge some previous assumptions about functional and dysfunctional ways of coping with excessive appetitive behaviour in the family.

Adaptation, Psychological↗
PubMed1998

NifA-dependent expression of glutamate dehydrogenase in Rhizobium etli modifies nitrogen partitioning during symbiosis.

Constitutive expression of foreign glutamate dehydrogenase in Rhizobium etli inhibits bean plant nodulation (A. Mendoza, A. Leija, E. Martínez-Romero, G. Hernández, and J. Mora. Mol. Plant-Microbe Interact. 8:584-592, 1995). Here we report that this inhibition is overcome when controlling gdhA expression by NifA, thus delaying the GDH activity onset after nodule establishment. Expression of gdhA modifies the nitrogen partitioning inside the bacteroid, where newly synthesized ammonia is preferentially incorporated into the amino acid pool instead of being exported to the infected cells. As a consequence, the fixed nitrogen transport to the leaves, measured as the ureides content in xylem sap, is significantly reduced. Nitrogenase activity, although not nifHDK expression, is significantly reduced in bacteroids expressing gdhA, probably due to the utilization of energy and reducing power for nitrogen assimilation. Here we show that ammonia assimilation inside R. etli bacteroids is active, albeit at low levels, and when enhanced is deleterious to the symbiotic performance. This leads us to believe that further reduction of the basal nitrogen metabolism in the bacteroid might stimulate the nitrogenase activity and increase the nitrogen supply to the plant.

Bacterial Proteins↗
PubMed1998

Poly-beta-hydroxybutyrate turnover in Azorhizobium caulinodans is required for growth and affects nifA expression.

Azorhizobium caulinodans is able to fix nitrogen in the free-living state and in symbiosis with the tropical legume Sesbania rostrata. The bacteria accumulate poly-beta-hydroxybutyrate (PHB) under both conditions. The structural gene for PHB synthase, phbC, was inactivated by insertion of an interposon. The mutant strains obtained were devoid of PHB, impaired in their growth properties, totally devoid of nitrogenase activity ex planta (Nif-), and affected in nucleotide pools and induced Fix- nodules devoid of bacteria. The Nif- phenotype was the consequence of the lack of nifA transcription. Nitrogenase activity was partially restored to a phbC mutant by constitutive expression of the nifA gene. However, this constitutive nifA expression had no effect on the nucleotide content or on growth of the phbC mutant. It is suggested that PHB is required for maintaining the reducing power of the cell and therefore the bacterial growth. These observations also suggest a new control of nifA expression to adapt nitrogen fixation to the availability of carbon and reducing equivalents.

Acyltransferases↗
PubMed1998

[Use of 99mTc-tetrofosmin scintigraphy in the diagnosis of patients with hyperparathyroidism].

UNLABELLED: The aim of the work was to study the diagnostic value of 99mTc-tetrofosmin to localize anomalous parathyroid glands in patients with hyperparathyroidism. METHODS: We have studied 33 patients: 12 with primary and 21 with secondary hyperparathyroidism, 9 of them renal graft recipients. Sixteen patients underwent surgery, 12 with primary and 4 with secondary hyperparathyroidism. All patients were injected with 740 MBq of 99mTc-tetrofosmin. Subsequently at 15, 30 and 60 minutes images were acquired for 300 seconds using a pin-hole collimator. A pertechnetate thyroid scintigraphy was obtained in 7 cases (24-48 h later) when the thyroid activity made difficult the identification of parathyroid glands. RESULTS: In the group of patients with primary hyperparathyroidism, all cases showed a focal uptake in lower right localization. In the secondary hyperparathyroidism group, 12 patients showed diffuse tracer uptake in two or more glands and histology confirmed hyperplasia in four of them. Seven cases showed a greater focal uptake in a gland: two of them were renal graft recipients and three were chronic renal failure cases in haemodyalisis, and two were evaluated postsurgery showing uptake in the remnant parathyroid gland. The two remaining patients had a normal scintigraphy and corresponded to two false negative cases. In conclusion, our results suggest that 99Tc-tetrofosmin may be used as a suitable tracer for preoperative detection and screening of anomalous parathyroid glands.

Adenoma↗
PubMed1998

[Radionuclide scan with TC-99m-tin colloid in the evaluation of orthopedic implant infections].

We have studied 26 patients (32-77 years old, 16 females) with suspicion of joint arthroplasty infection: 11 total hip replacements, 12 total knee replacements and 3 osteosinthesys. A bone scintigraphy with MDP-99mTc, a scintigraphy with HMPAO-WBC and a scintigraphy with 99mTc-stannous colloid were made in all patients. The final diagnostic was based in joint cultures and clinic and radiologic evolution of the patients. The earliest phase of the bone scintigraphy was positive in 18 patients. The later phase was positive in all them. The WBC was positive in 20 out of 26 patients. The bone marrow scintigraphy showed a congruent pattern with WBC in 18 patients (17 infected and 1 without infection). The other ones (8 patients) showed an incongruent pattern (7 with infection and 1 without it). The results show that the bone marrow scintigraphy with 99mTc-stannous colloid improves the accuracy of the diagnostic of bone prosthesis infection and should be included into the diagnosis protocol of this disease.

Adult↗
PubMed1998

[Effective renal plasma flow with I-131-hipuran: evaluation of a method with four extractions].

The aim of this work was to evaluate a method for the estimation of the effective renal plasma flow (ERPF) using sodium 131I-o-hippurate (OIH) by means the bicompartmental analysis of the radioactive concentration of 4 plasma samples, analyzing the error obtained respecting to the multi-sample method and comparing it with those obtained with other simplified methods. We calculated the ERPF from 62 patients using the multi-sample method as standard, the method based in a single sample at 44 minutes p.i., a method based in 2 samples from the first exponential, 4 methods based in 2 samples from the second exponential, one method based in 3 samples and 5 methods based in 4 samples (2 from the first exponential and 2 from the second exponential). Each simplified method was compared to the standard method and their absolute error (AE) and standard estimation error (SEE) were calculated. The method based in the 4 samples withdrawn at 4, 10, 30 and 60 minutes p.i. was the best of them with a correlation factor with the standard equal to 0.997, an EA that ranged from -63 ml/min to 49 ml/min (mean: -4 ml/min) and a SEE of 19.5 ml/min.

Body Fluid Compartments↗
PubMed1998

K-ras gene mutations in the diagnosis of fine-needle aspirates of pancreatic masses: prospective study using two techniques with different detection limits.

Detection of K-ras mutations may be useful in the evaluation of pancreatic cancer. The aim of this study was to assess, in a prospective design, the diagnostic utility of K-ras mutation analysis in 62 consecutive fine-needle aspirates of pancreatic masses, using two PCR-based techniques-standard and enriched-with detection limits of a mutant allele in the presence of 10(2) or 10(3) wild-type alleles, respectively. Cytology alone offered a diagnostic sensitivity of 75%. The enriched higher sensitivity detection technique, in combination with cytology, offered a diagnostic sensitivity of 91% without false positives. The molecular analysis would have contributed to diagnosis in an additional 14 cases of pancreatic cancer. The standard technique contributed to diagnosis in an additional 9 cases. These results strongly support the use of the enriched method of detecting K-ras mutations as a complement to cytology in the evaluation of pancreatic masses.

Aged↗
PubMed1998

[Nonmetastatic accumulations in bone radionuclide scans in a patient with breast neoplasm].

A 51 year old woman with breast cancer four years ago was studied by bone scintigraphy. At the moment of the study she had bone pain. The bone scintigraphy showed uptake in humerus and femur and no more uptake in other zones of axial skeleton. Then, we made others radiological procedures (X-Ray and MRI) with the aim to make an accurate diagnosis. Then a diagnosis of benign bone tumours; enchondroma was made. It means something obvious but very interesting. In case of doubt we ever have to compare the bone scintigraphy with other diagnostic. examinations.

Bone Neoplasms↗
PubMed1997

Regulation of pyruvate carboxylase in Rhizobium etli.

Pyruvate carboxylase (PYC) is a biotin-dependent enzyme catalyzing the anaplerotic conversion of pyruvate to oxaloacetate in Rhizobium etli strain CE3. A pyc::Tn5 mutant had severely reduced growth, or failed to grow on sugars, three-carbon organic acids or glycerol, consistent with these substrates being metabolized via pyruvate. Transconjugants expressing a pyc::beta-glucuronidase gene fusion had slightly increased apparent pyc transcription during growth on pyruvate as compared to succinate, similar to the modest carbon source dependent changes in PYC activity reported previously. Biotin supplementation of cultures growing on pyruvate dramatically increased PYC activity but not apparent pyc transcription. Bacteroids isolated from bean nodules did not contain detectable PYC activity while apparent pyc transcription occurred at a moderate level.

Bacterial Proteins↗
PubMed1997

Renogram deconvolution in the management of diabetic nephropathy: utility of the measurement of initial tracer uptake.

Our objective was to assess mean transit time (MTT) and initial uptake, both parameters derived from the renal retention function (RRF), in the study of renal function in patients with diabetic nephropathy. We studied 25 patients, 7 with type I diabetes mellitus and 18 with type II diabetes mellitus, all of whom fulfilled the criteria for diabetic nephropathy with proteinuria and/or retinopathy. We found a statistically significant correlation between initial uptake and the other biochemical and renographic parameters studied except proteinuria: serum creatinine (r = 0.66, P < 0.002), creatinine clearance (r = 0.61, P < 0.003), glomerular filtration rate (r = 0.74, P < 0.003) and effective renal plasma flow (r = 0.66, P < 0.003). The other renographic parameters studied (maximal activity of the conventional renogram and MTT of the deconvoluted renogram) did not show any correlation. Initial uptake is a semi-quantitative renographic parameter that can provide complementary information to biochemical data and it may be useful in the management of diabetic nephropathy, especially in patients with high serum creatinine or creatinine clearance.

Adult↗
PubMed1997

Expression of thiamin biosynthetic genes (thiCOGE) and production of symbiotic terminal oxidase cbb3 in Rhizobium etli.

In this paper we report the cloning and sequence analysis of four genes, located on plasmid pb, which are involved in the synthesis of thiamin in Rhizobium etli (thiC, thiO, thiG, and thiE). Two precursors, 4-methyl-5-(beta-hydroxyethyl)thiazole monophosphate and 4-amino-5-hydroxymethylpyrimidine pyrophosphate, are coupled to form thiamin monophosphate, which is then phosphorylated to make thiamin pyrophosphate. The first open reading frame (ORF) product, of 610 residues, has significant homology (69% identity) with the product of thiC from Escherichia coli, which is involved in the synthesis of hydroxymethylpyrimidine. The second ORF product, of 327 residues, is the product of a novel gene denoted thiO. A protein motif involved in flavin adenine dinucleotide binding was found in the amino-terminal part of ThiO; also, residues involved in the catalytic site of D-amino acid oxidases are conserved in ThiO, suggesting that it catalyzes the oxidative deamination of some intermediate of thiamin biosynthesis. The third ORF product, of 323 residues, has significant homology (38% identity) with ThiG from E. coli, which is involved in the synthesis of the thiazole. The fourth ORF product, of 204 residues, has significant homology (47% identity) with the product of thiE from E. coli, which is involved in the condensation of hydroxymethylpyrimidine and thiazole. Strain CFN037 is an R. etli mutant induced by a single Tn5mob insertion in the promoter region of the thiCOGE gene cluster. The Tn5mob insertion in CFN037 occurred within a 39-bp region which is highly conserved in all of the thiC promoters analyzed and promotes constitutive expression of thiC. Primer extension analysis showed that thiC transcription in strain CFN037 originates within the Tn5 element. Analysis of c-type protein content and expression of the fixNOQP operon, which codes for the symbiotic terminal oxidase cbb3, revealed that CFN037 produces the cbb3 terminal oxidase. These data show a direct relationship between expression of thiC and production of the cbb3 terminal oxidase. This is consistent with the proposition that a purine-related metabolite, 5-aminoimidazole-4-carboxamide ribonucleotide, is a negative effector of the production of the symbiotic terminal oxidase cbb3 in R. etli.

Amino Acid Sequence↗
PubMed1997

Within-subject variation of carcinoembryonic antigen in colorectal cancer -- application of reference of change values and individual reference ranges to patient follow-up.

Dynamic interpretation of results is an alternative approach to the conventional cut-off procedure. Reference change limit is a valuable reference point to interpret dynamically tumour marker values when only very few serial results can be obtained from a patient after treatment. In this paper, a reference change limit of 2.0 microg/l was estimated for carcinoembryonic antigen in patients with complete remission of colorectal cancer. This figure means that a difference greater than 2.0 microg/l has at least a chance of being statistically significant (at 0.05 probability). As complementary information to the reference change limits, with more than four successive results, a simple time series model can be used to obtain predictive limits for the next observation.

Adenocarcinoma↗