Search PubMed⌕ Search

Biomedical subjects

C Fernandez

Publications and source records attributed to C Fernandez.

At least 163 records · Page 9Linked to original sources
PubMed1989

Giant-cell tumor of bone, stage II, displaying translocation t(12;19)(q13;q13).

A new case of giant-cell tumour (GCT) of bone with benign histological features, clinical stage II, has been reviewed with immunohistochemistry and electron microscopy. After short-term tissue culture the karyotype, using G-banding techniques, presented a consistent translocation t(12;19)(q13;q13). Nude mice xenografts of the tumour were unsuccessful after 6 months of follow-up. Presence of such chromosomal rearrangement may be related to locally aggressive, histologically benign giant-cell tumors of bone.

Adult↗
PubMed1989

Biliary excretion and choleretic effect of cefmetazole in rats.

The effect of cefmetazole, a broad-spectrum cephalosporin, on bile flow and composition in rats was studied. Intravenous injection of cefmetazole at doses ranging from 40 to 400 mumol/kg of body weight led to an increase in its biliary concentration and excretion rate, with a maximum at 30 min after injection. Excretion of cefmetazole into bile was associated with a marked choleresis. The magnitude of the increase in bile flow was dose dependent, with a maximal increase at a dose of 200 mumol/kg. Cefmetazole administration did not affect the secretion of bile acids or their osmotic activities, whereas the bile acid-independent bile flow increased by 49% at a dose of 200 mumol/kg. Cefmetazole administration at a dose of 200 mumol/kg significantly increased the biliary outputs of sodium, potassium, chloride, and bicarbonate (+36, +56, +28, and +31%, respectively) compared with outputs of controls. A linear relationship was observed between bile flow and cefmetazole excretion, 44 microliters of bile being produced per mumol of cefmetazole excreted into bile. Our results demonstrate that cefmetazole induces choleresis by stimulating bile acid-independent bile flow. This effect appears to be partly due to the osmotic properties of cefmetazole transported into bile.

Animals↗
PubMed1989

Quality of life during chemotherapy in non-small cell lung cancer patients.

To evaluate the usefulness of chemotherapy in non-small cell lung cancer, objective response, length of remission and survival have been considered the main yardsticks. Subjective improvement and gain in Karnofsky performance status have attracted very little attention. Thirty-one patients with stages III and IV underwent combination chemotherapy with high-dose cisplatin, and were assessed with categorical scales and 100 mm visual analogue scales used by patients themselves to report on several symptoms of their illness. After chemotherapy 17 of 19 patients (89%) gained weight; 20 presented anorexia, 10 of those (50%) improved; 15 had pain, 7 of those (47%) were alleviated; cough was reported in 22, in 10 (45%) it was ameliorated; hemoptysis disappeared in 10 of 11 patients (91%); of the 9 patients who had dyspnea, 7 improved (78%); and astenia was attenuated in 8 of 16 patients (50%). Quality of life was reported improved in 75% of those patients who had considered themselves seriously affected prior to the treatment. When compared with Karnofsky performance status, no relationship was found (r = 0.31). It is concluded that, apart from the objective response achieved, a significant proportion of patients did benefit from treatment as demonstrated by a marked relief of symptoms.

Antineoplastic Agents↗
PubMed1988

Plasma and urinary heparin cofactor II levels in patients with nephrotic syndrome.

Heparin cofactor II (HC II) levels were measured by electroimmunoassay in plasmas and urines from 68 patients with nephrotic syndrome. In addition, antithrombin III (AT III) and protein C (PC) activities and antigens were measured also in the same group of patients. Seven of these patients had histories of thrombosis. Plasma HC II levels (mean +/- SD 105 +/- 43) were not different from levels in healthy subjects (94 +/- 17). Only 5 patients had low plasma levels of HC II. None of the patients with thrombosis had low HC II levels. Even though measurable amounts of HC II were found in 25 urines from 50 patients. There was a relationship in the urinary excretion between HC II and AT III and their urinary clearances were quite similar. However, no correlation was found between plasma HC II and AT III levels, and levels of AT III activity and antigen were significantly lower than in healthy subjects. Three patients with histories of thrombosis had low AT III levels. Most patients (including those with thrombosis histories) had high plasma PC levels and increased urinary loss. It is suggested that HC II does not play an important role in the pathogenesis of thrombosis in nephrotic syndrome.

Adolescent↗
PubMed1988

Evidence for central entrainment of the medullary respiratory pattern by the locomotor pattern in the rabbit.

1) Although periodic passive hindlimb movements can reproduce the enhancement of breathing frequency seen at the onset of muscular exercise, we have shown previously that they were unable to induce the 1:1 coupling which is observed between locomotion and respiration during galloping in quadrupeds. The purpose of this study was to investigate the existence of a central coupling in two experimental situations: first, decorticate - DOPA, and secondly, decerebrate rabbit preparations. 2) After DOPA administration in curarized, vagotomized, decorticate animals, an absolute coordination could be observed between the locomotor bursts (which developed in hindlimb muscle nerves) and phrenic activity. With the temporal evolution of the pharmacological activation, the coupling mode varied from 1:1 to 1:2 during the same experiment with a loss of coordination between these two forms. When the coordination between both motor activities was not produced in such conditions, it could be induced for some imposed frequencies of periodic passive motions applied to the contralateral hindlimb. 3) When the DOPA effects were completely over, a rostro-pontine decerebration allowed locomotor activity to be released and a tight 1:1 coupling could be obtained again between the two motor patterns in this new experimental situation. 4) An analysis of the data revealed that the various forms of coordination obtained in the different experimental situations are due to a central resetting of the respiratory and of the locomotor patterns. The capability of the hindlimb proprioceptive inputs to coordinate locomotor and respiratory patterns in the decorticate-DOPA preparation appeared simply linked to their ability to entrain the activity of the lumbar locomotion generator. It is suggested that these central reciprocal interactions, which have the properties of an entrainment process, are the result of interactions between the lumbar locomotion generator and the medullary respiratory one.

Action Potentials↗
PubMed1988

cDNA cloning, sequence, and regulation of a major female-specific and growth hormone-inducible rat liver cytochrome P-450 active in 15 beta-hydroxylation of steroid sulfates.

cDNA clones encompassing the complete coding sequence for the female-specific rat liver microsomal 15 beta-hydroxylase have been isolated and sequenced. This cytochrome P-450 species (P-450 15 beta) has a total of 490 amino acid residues, and its deduced amino acid sequence as well as direct sequencing of the amino-terminal portion of the purified protein revealed its identity with P-450 i. P-450 15 beta was found to be 66% similar to the male-specific rat liver microsomal 16 alpha-hydroxylase, P-450 16 alpha. Furthermore, P-450 15 beta is 47% similar to the major phenobarbital-inducible cytochrome P-450 in rat liver, P-450 b, while its structural similarity to P-450 c, P-450 pregnenolone-16a-carbonitrile, and P-450 lauric acid omega-hydroxylase is less than 30%. However, the developmentally regulated cytochromes P-450 f and P-450 PB-1 both have 68% similarity to P-450 15 beta. It is therefore concluded that P-450 15 beta belongs to the same gene subfamily (P450IIC) that also includes cytochromes P-450 f, PB-1, and 16 alpha. The plasma pattern of growth hormone (GH) is known to be a major determinant for the sex-specific expression of P-450 15 beta and P-450 16 alpha. Continuous infusion of GH to hypophysectomized male rats causes an increase in P-450 15 beta mRNA after 6 days of treatment, while intermittent injections have no effect. On the other hand, no effect on P-450 16 alpha mRNA is observed after continuous administration of GH, while intermittent injections cause an increase after 2 days of treatment. This relatively long period before P-450 15 beta and P-450 16 alpha mRNA induction is seen might indicate that protein factors mediating GH action are involved.

Amino Acid Sequence↗
PubMed1987

A randomized study comparing platinum, doxorubicin, and VP-16 with platinum, 4'-epidoxorubicin, and VP-16 in patients with non-small-cell lung cancer.

Forty-four previously untreated patients with advanced non-small-cell lung cancer were treated in a randomized trial comparing platinum (60 mg/m2), doxorubicin (40 mg/m2), and VP-16 (150 mg/m2) (PAV) with platinum (60 mg/m2), 4'-epidoxorubicin (50 mg/m2), and VP-16 (150 mg/m2) (PEV). The overall response rate was 10%. Major response rates were quite similar for the 21 patients treated with PAV (5%) and the 23 patients treated with PEV (18%) (p = 0.2). Of the 23 patients with assigned to PEV, two (9%) achieved complete responses for a median duration of 20 weeks and 44+ weeks. There was no significant difference (p = 0.75) in the median survival among patients treated with PAV (24 weeks) and those treated with PEV (20 weeks). Toxicity was generally mild and tolerable. The lack of response found in both arms of treatment caused the study to be terminated early. Some benefit could be appreciated in patients with limited disease and good Karnofsky performance status.

Adenocarcinoma↗
PubMed1987

Inputs from regularly and irregularly discharging vestibular nerve afferents to secondary neurons in the vestibular nuclei of the squirrel monkey. I. An electrophysiological analysis.

1. The electrical excitability of vestibular nerve afferents is related to their discharge regularity (23). Irregular (I) afferents are more excitable than regular (R) afferents. We explored the possibility that the differences in electrical excitability could be used to determine the profile of monosynaptic inputs from the ipsilateral vestibular nerve (Vi) to secondary neurons of the vestibular nuclei. The growth of monosynaptic Vi excitatory postsynaptic potentials (EPSPs) as shock strength is increased should reflect the kinds of afferent input that a secondary neuron receives. We were particularly interested in seeing if cells in the vestibular nuclei could be distinguished as R or I neurons depending on whether they received predominantly regular or irregular inputs. Barbiturate-anesthetized squirrel monkeys were used. 2. Recordings were made from vestibular nerve afferents. Shock strength was expressed as multiples of T, the value needed to recruit 10% of the afferents or, as determined empirically, to evoke a detectable field potential in the vestibular nuclei. Most I afferents (85/87 = 98%) were recruited below 4 X T, whereas most R afferents (197/212 = 93%) were first activated above 4 X T. The relation between latent period and electrical excitability was flat for units with thresholds in the range 1-4 X T. Latent periods increased for units with higher thresholds, especially those first activated above 8 x T. The threshold differences between I and R afferents are maximal if the shock falls at approximately half the mean interval after a naturally occurring action potential. The same results were obtained by having each unit fire to a maximal (16-32 X T) conditioning shock and then determining the threshold to a test shock presented 4 ms later. The latter stimulus configuration was used to study the Vi monosynaptic inputs to secondary neurons. The test shock was raised by successive doublings from 1 X T to the strength of the conditioning shock (16-32 X T). 3. Intracellular recordings were made from neurons located in the superior vestibular nucleus or the rostral parts of the medical or lateral vestibular nuclei. Amplitudes and latent periods of Vi EPSPs were measured from averages of several repetitions of each stimulus pair. Each EPSP was calculated by subtracting the extracellular from the intracellular averaged response. Of the 122 neurons sampled, 115 were judged to be monosynaptically related to the ipsilateral vestibular nerve because their Vi EPSPs had latent periods in the range of 0.7-1.4 ms.(ABSTRACT TRUNCATED AT 400 WORDS)

Action Potentials↗
PubMed1986

A preliminary study of urinary transferrin as a marker for prostatic cancer.

Traditional serum markers used in the diagnosis of prostate cancer lack sensitivity and specificity. Prostatic fluid is in direct contact with the prostate epithelium and, thus, has been investigated as a better source for potentially useful markers. Since prostatic fluid contents can enter the urine directly through the urethra, without prerequisite entry into blood, proteins present in significant quantities in prostatic fluid represent candidate markers for entry into the urine, particularly in diseases affecting the prostate epithelium, such as adenocarcinoma. High concentrations of transferrin in prostatic fluid led us to examine urine transferrin levels, using an immunoturbidimetric technique. Urine transferrin was significantly increased in 18 out of 22 patients with prostate cancer in comparison to age-matched controls. Since there was no evidence of increased transferrin excretion, we suggest that prostatic fluid is the source of transferrinuria.

Aged↗
PubMed1986

Spontaneous insertions into cosmid vector: a warning.

During the course of characterization of a human genomic library we found that some of the selected pNNL cosmid clones carried only very short inserts. In addition, several clones that did contain full-length inserts were found to be unstable and generated repeated deletions of various portions of their inserts. Moreover, all the clones examined displayed rearrangements in the vector portions. The rearranged clones that were characterized by restriction mapping were found to have deletions starting between ClaI and HindIII in the region of the cos segment of the pNNL vector used in the construction of the library. We determined the nucleotide sequence of the 1300-bp EcoRI-PvuII segment located in the cos region, and by the computer search we found that it contains Escherichia coli insertion elements IS1.

Base Sequence↗
PubMed1985

Carbon dioxide embolism during laparoscopy and hysteroscopy.

Venous carbon dioxide embolism is a rare but potentially lethal complication of laparoscopy. The risk is increased when it is associated with hysteroscopy. A case is presented of a young women undergoing laparoscopy and hysteroscopy for infertility. Cardiovascular collapse and cardiac arrest, associated with a mill-wheel murmur, occurred during hysteroscopy at the time of a change of position. The patient had irreversible brain damage and died a week later. Early diagnosis and prevention of this serious complication are discussed.

Adult↗
PubMed1984

[Hemodynamic effects of 2 different doses of midazolam in combination with fentanyl for induction of anesthesia in surgery of the abdominal aorta].

The haemodynamic effects of anaesthetic induction with midazolam, fentanyl and pancuronium bromide were studied in two groups of patients undergoing abdominal aortic surgery: group A (10 patients receiving 0.2 mg X kg-1 midazolam) and group B (9 patients receiving 0.3 mg X kg-1 midazolam). Haemodynamic parameters were measured before induction after fluid loading and 15 min after induction. Heart rate, mean right atrial pressure, systemic and pulmonary vascular resistances, mean pulmonary wedge pressure and right ventricular stroke work index remained steady. On the other hand, mean arterial and pulmonary arterial pressures, systolic, cardiac and left ventricular stroke work indices fell significantly in both groups. However there was no statistically significant difference between the two groups.

Anesthesia, General↗