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Biomedical subjects

J Mata

Publications and source records attributed to J Mata.

At least 37 records · Page 2Linked to original sources
PubMed1993

Intravascular ultrasound study of angiographically mildly diseased coronary arteries.

OBJECTIVES: We hypothesized that intravascular ultrasound may identify significant coronary artery narrowing in the mildly diseased coronary artery of patients with insignificant or one- or two-vessel coronary artery disease. BACKGROUND: Necropsy studies have revealed that coronary angiography may underestimate stenosis severity in vessels that appear mildly diseased. Intravascular ultrasound has been shown to detect atherosclerotic changes in angiographically normal coronary arteries and to correlate better with histologic findings. METHODS: In 20 patients, we performed intravascular ultrasound imaging (3.5F catheter, 30-MHz transducer) in 37 coronary arteries that were considered mildly diseased (<50% diameter narrowing) by qualitative angiography. The angiographic diagnosis was no significant coronary artery disease in eight patients, one-vessel disease in seven and two-vessel disease in five. Each vessel, except for the left main coronary artery, was divided into proximal, mid and distal segments. Percent area narrowing and minimal lumen diameter were subsequently quantified by both ultrasound and quantitative angiography. RESULTS: Mean maximal arterial area narrowing by ultrasound in the 67 segments studied was 36 +/- 20% (range 0% to 80.2%) and 19 +/- 23% (range 0% to 82%) by quantitative angiography of these same segments (p < 0.001, paired t test). Mean minimal lumen diameter of the segment was 3.3 +/- 0.9 mm by ultrasound and 2.7 +/- 0.8 mm by quantitative angiography. In 10 patients there were 19 angiographically mildly diseased segments where the percent arterial area narrowing by ultrasound was > or = 50%. Intravascular ultrasound revealed that the more proximal (reference) segment had > 25% intimal thickening in 12 of the 19 underestimated segments. In six stenosed segments (32%), total vessel area increased compared with that of the adjacent proximal vessel segment because of compensatory dilation. CONCLUSIONS: Intravascular ultrasound identifies potentially significant coronary artery disease in vessels that appear to be only mildly diseased by angiography.

Constriction, Pathologic↗
PubMed1992

Annular submitral left ventricular aneurysm.

Annular subvalvular aneurysms have been reported rarely in Caucasian individuals. We describe the case of a white man who had an asymptomatic annular submitral left ventricular aneurysm diagnosed during the diagnostic work-up of cervical lymphadenopathies. Our case is unique because of its occurrence in a Caucasian and its characteristic radiological features.

Adult↗
PubMed1992

Twin pregnancies: accuracy of first-trimester abdominal US in predicting chorionicity and amnionicity.

A first-trimester transabdominal ultrasound (US) study was performed on twin pregnancies to determine the utility of US in predicting chorionicity and amnionicity. Among 85 dichorionic-diamniotic (DC-DA) twin pairs, a thick membrane was present in 78 (92%). Four of the DC-DA cases without a thick membrane had two distinct placental sites, allowing 82 DC-DA pregnancies (96%) to be predicted. Among 16 monochorionic-diamniotic (MC-DA) twin pairs, a thin membrane was present in 14 (88%). None of the four monochorionic-monoamniotic (MC-MA) cases had an identifiable membrane. The lambda sign had no value in this evaluation and was actually misleading, while a thick membrane or the identification of two separate placentas was always predictive of DC-DA twinning. However, a thin membrane, while usually predictive of an MC-DA pregnancy, did not exclude a DC-DA gestation. When no membrane is present, an MC-MA gestation is probable; however, a diamniotic pregnancy may still be present, and further evaluation is suggested.

Amnion↗
PubMed1991

Imaging of the azygos lobe: normal anatomy and variations.

We describe the normal appearance of the azygos lobe on plain radiography and CT. Several findings are presented that, to our knowledge, have not been previously reported, such as the inferior prolongation of the fissure, the apparent intrapulmonary path of the right brachiocephalic vein and superior vena cava seen on the anteroposterior chest radiograph, and the visible fissure on the lateral chest radiograph.

Azygos Vein↗
PubMed1990

Bowel injury as a result of penetrating scrotal trauma: review of associated injuries.

We report a case of bowel injury as a result of an isolated gunshot wound to the scrotum. Our experience with penetrating scrotal trauma reveals a high rate of associated injuries, the most common being trauma to the soft tissue of the thigh. Our case emphasizes the importance of a thorough preoperative and operative evaluation of patients with penetrating scrotal trauma.

Humans↗
PubMed1989

Echogenic focus in the gastrointestinal wall as a sign of ulceration.

An ultrasound study carried out on 22 patients with ulcerated gastrointestinal lesions (20 adenocarcinomas and 2 peptic ulcers) showed, in all cases, an echogenic focus (EF) that was situated in the gastrointestinal wall. In order to find out the histopathologic significance of this focus and its location, an examination was made "in vitro" of 8 surgical specimens obtained from gastrectomies--6 from peptic and 2 from malignant ulcers. The specimens were immersed in a water bath using a 5-MHz transducer. A common finding in all the specimens was an EF similar to that seen in the clinical study and situated behind the crater of the ulcer. In this location the histopathologic findings demonstrated necrotic and inflammatory material in both the benign and malignant lesions.

Adenocarcinoma↗
PubMed1989

Prognostic significance of lymph nodal metastases in prostate cancer.

Pelvic lymph node metastases indicate a poor prognosis for patients with clinically localized prostate cancer but the significance of minimal nodal metastases still is debated. We determined the progression and cancer specific survival rates based on the extent of nodal metastases in 511 patients followed for a mean of 8.6 years (range 2.5 to 17.5 years) after bilateral pelvic lymph node dissection and irradiation therapy. The patients were divided into 4 groups based on the extent of nodal metastases: NO--negative nodes (359 patients), N1--a single microscopic positive node (37), N2--multiple microscopic positive nodes (86) and N3--grossly positive or juxtaregional nodes (29). The risks of distant metastases and of dying of prostate cancer were much greater in the 152 patients with positive nodes (N+) than in those with negative nodes (p less than 0.00005). The risk of metastatic disease at 10 years was only 31 +/- 7 per cent for the NO patients compared to 83 +/- 7 per cent for the N+ patients, and the risk of dying of prostate cancer was only 17 +/- 6 per cent at 10 years for the NO group and 57 +/- 11 per cent for the N+ patients. Patients with a single microscopic node (N1) had a pattern of progression and cancer specific mortality rate similar to patients with more extensive nodal metastases and markedly worse than patients with negative nodes. The risk of distant metastases was 80 +/- 15 per cent at 10 years for the N1 group, 84 +/- 11 per cent for the N2 group and 88 +/- 13 per cent for the N3 group, while the risk of dying of prostate cancer at 10 years was 40 +/- 19, 66 +/- 15 and 58 +/- 24 per cent, respectively. The finding of a single pelvic lymph node containing microscopic metastatic disease markedly worsened the prognosis of our patients with prostate cancer. Once prostate cancer is found within the pelvic lymph nodes the patient has systemic disease unlikely to be controlled by pelvic lymph node dissection and radiotherapy.

Actuarial Analysis↗
PubMed1988

Pulmonary nodule simulated on the lateral chest radiograph by branches of the aortic arch.

A prospective study of 500 lateral radiographs of the chest showed a nodular opacity superimposed on the trachea above the aortic arch in 15 patients (3%). Because no abnormalities were identified on the posteroanterior radiograph or on CT scans, we assume that this pseudonodule is produced by branches of the aorta. In all cases, CT showed that the left subclavian artery or the innominate artery-right subclavian complex protruded into the lung.

Adolescent↗
PubMed1987

Kinetically controlled enzyme-catalyzed synthesis of kyotorphin. An optimization study.

Regarding the alpha-chymotrypsin-catalyzed synthesis of Z-Tyr-Arg-NH2, the effect on the reaction yield of the following experimental factors is discussed: DMF/buffer proportions, reaction temperature, and donor/nucleophile ratios. The experimental design shows that relatively better yields are obtained by increasing the reaction temperature and lowering the cosolvent proportion while maintaining a slight excess of nucleophile. The ascensional line reaches an optimal response surface very flat voided of a well-defined maximum.

Analgesics↗
PubMed1982

[Epidemiology of leukemia in children in Valencia (author's transl)].

The incidence of leukemia in Valencia in children zero-seven years old, during a period of ten years (1970-1979), is studied. One hundred and fifty five cases of leukemia were diagnosed on five hospitals during this time. This makes an incidence of 3.5 cases per 100,000 children and years. A light predominance of males was observed and the peak age of presentation was between two and five years. Acute lymphoblastic leukemia was the more frequent variety, followed a big distance by acute myeloid. The relation with other factors, as chromosome abnormalities, parents age, socioeconomic level, are also studied.

Age Factors↗
PubMed1979

Congenital mesoblastic nephroma.

A case of mesoblastic nephroma in an infant with a 3-year, disease-free, postoperative survival period is reported. The histological aspects, with emphasis on differential diagnosis from Wilm's tumour are described.

Child, Preschool↗
PubMed1975

Nephromegaly in Hemophilia.

Various renal abnormalities have been reported in patients with hemophilia. Findings in four patients with hemophilia and nonobstructive renal enlargement are described. Three of these patients also had pseudotumors of the iliac bone. The one factor common to all of these patients and patients with sickle cell anemia or thalassemia with large kidneys is multiple blood transfusions.

Adult↗
PubMedDate not supplied

Complex regulation of nucleoside transporter expression in epithelial and immune system cells.

Nucleoside transporters have a variety of functions in the cell, such as the provision of substrates for nucleic acid synthesis and the modulation of purine receptors by determining agonist availability. They also transport a wide range of nucleoside-derived antiviral and anticancer drugs. Most mammalian cells co-express several nucleoside transporter isoforms at the plasma membrane, which are differentially regulated. This paper reviews studies on nucleoside transporter regulation, which has been extensively characterized in the laboratory in several model systems: the hepatocyte, an epithelial cell type, and immune system cells, in particular B cells, which are non-polarized and highly specialized. The hepatocyte co-expresses at least two Na+-dependent nucleoside transporters, CNT1 and CNT2, which are up-regulated during cell proliferation but may undergo selective loss in certain experimental models of hepatocarcinomas. This feature is consistent with evidence that CNT expression also depends on the differentiation status of the hepatocyte. Moreover, substrate availability also modulates CNT expression in epithelial cells, as reported for hepatocytes and jejunum epithelia from rats fed nucleotide-deprived diets. In human B cell lines, CNT and ENT transporters are co-expressed but differentially regulated after B cell activation triggered by cytokines or phorbol esters, as described for murine bone marrow macrophages induced either to activate or to proliferate. The complex regulation of the expression and activity of nucleoside transporters hints at their relevance in cell physiology.

Animals↗
PubMedDate not supplied

[Adenocarcinoma in bladder. Apropos of a case].

Finding an adenocarcinoma at the vesicle suggests three possible diagnosis: Intestinal adenocarcinoma with vesical location. Adenocarcinoma of the urachus. Vesical primitive adenocarcinoma. Presentation of one case of intestinal adenocarcinoma, revealed by its mictional symptomatology, with the endoscopic appearance of being a single vesical tumour, later shown to be a vesical adenocarcinoma, on which extended surgery of the gut and partial surgery of the bladder was performed.

Adenocarcinoma↗