We have isolated cDNA and genomic clones corresponding to a gene highly and specifically expressed at the late stage of fruit-ripening in bell-pepper. Antibodies raised against the expressed protein allowed determination of the cellular localization of the gene product. The encoded protein is present only in chromoplasts from fully-ripe red fruits, as shown by Western analysis and import experiments. The corresponding mRNA accumulates to high levels during ripening at orange and red stages, but is not detected in yellow varieties impaired in the synthesis of ketocarotenoids. Several lines of evidence indicate that the encoded protein is an oxido-reductase involved in the synthesis of capsanthin and capsorubin.

Amino Acid Sequence↗

PubMedDate not supplied

Outcome of peptic ulcer hemorrhage treated according to a defined approach.

The short- and long-term bleeding recurrence and mortality of 157 consecutive patients admitted emergently over a period of 2 years with an actively bleeding peptic ulcer were analyzed. They were treated uniformly according to a defined approach where suitable candidates for surgery were operated on early. The data of the 5-year follow-up were analyzed by constructing life tables. There were 94 men and 63 women with a median age of 72.3 years; 83 ulcers were gastric and 74 duodenal. Thirty-one patients underwent an operation. Eleven patients (7%) died within the first month, one in the surgical group. During the follow-up 13 patients rebled and 54 died, two of the deaths related to peptic ulcer disease. The life table for rebleeding and ulcer-related deaths showed a cumulative risk of 11.8% at 5 years, and the cumulative risk was not statistically different between patients according to their age (60 years and older versus younger), sex, the site of their ulcer (gastric versus duodenal), or the type of treatment (conservative versus surgical). With a well defined approach and early selective surgery, the short-term mortality compares favorably with the usual 10% or more reported. The high mortality rate during the follow-up reflects the advanced age of patients with coexisting disease. This long-term follow-up study could be used as a comparison against future studies evaluating new therapies.

Adolescent↗

PubMedDate not supplied

Disposition of 5-formyl- and 5-methyltetrahydrofolic acid in serum after i.v. bolus of calcium folinate: pharmacokinetic drug interaction with preadministered interferon-alpha-2b.

The influence of interferon (IFN) coadministered subcutaneously with the biomodulating agent folinic acid on the blood serum levels of 5-formyl-tetrahydrofolic acid (CHO-THFA) and the biotransformation into its main metabolite in the blood 5-methyltetrahydrofolic acid (CH3-THFA) was studied in patients receiving a chemotherapy with 5-fluorouracil. IFN causes a clear decrease of the serum concentrations of CHO-THFA and a statistically significant decrease of CH3-THFA concentrations (P < 0.01). The effect on serum concentrations could be observed in each patient, but in a different order of magnitude. As a consequence, the preadministration of IFN leads to a significant change in the basic pharmacokinetic parameters of both compounds: the mean area under the concentration-time curve is decreased at 27.4% for CHO-THFA (P < 0.025) and at 22.4% for CH3-THFA (P < 0.025), respectively. The total body clearance is elevated at 45.4% for CHO-THFA (P < 0.05) and at 23.4% for CH3-THFA (P < 0.05). The mean volume of distribution is increased by IFN at 38.2% for CHO-THFA (P < 0.025) and at 22.3% for CH3-THFA (P < 0.05). The nearly identical mean residence time in both groups indicates that CHO-THFA elimination is not affected by IFN. But the results prove a certain interaction between IFN and CHO-THFA. IFN accelerates the distribution of CHO-THFA as well as of its main metabolite from the blood into the tissue or activates the biotransformation of CHO-THFA into CH3-THFA inside the cells of the tissue. The extent of biotransformation of CHO-THFA into CH3-THFA, which takes place in the blood, is not influenced by IFN because percentage AUC-ratios CHO-THFA:CH3-THFA were 89.5:10.5% for the control group and 88.8:11.2% for the IFN group.

Aged↗

PubMedDate not supplied

Prediction of material properties from chemical structures. The clearing temperature of nematic liquid crystals derived from their chemical structures by artificial neural networks.

The prediction of properties of molecules just on the basis of their chemical structures is desirable to selectively make molecules that have the wanted properties, like biological activity, viscosity, or toxicity. Here, we present an example of a new way to predict a property from the chemical structure of a chemically heterogeneous class of compounds. The clearing temperatures of nematic liquid-crystalline phases of 17383 compounds were used to train neural networks to derive this material property directly from their chemical structure. The trained neural networks were subsequently tested with 4345 structural patterns of molecules unknown to the networks to assess their predictive value. The clearing temperatures were predicted by the best network with a standard deviation of 13 degrees.

Crystallization↗

PubMedDate not supplied

Intracranial manifestation of osteosarcoma.

Involvement of the central nervous system in osteosarcoma is uncommon. These neoplasms are most often located at the metaphyses of tubular bones and rarely in flat bones of vertebra, ribs, pelvis, facial bones, or skull. Tumors of the latter bones may obviously spread into the cerebrum. Osteosarcomas primarily metastasize hematogenously to the lungs. Bone, lymph node, or brain metastases are mostly seen following or concomitantly with pulmonary metastatic disease. However, there are single cases of primary osteosarcoma of the brain parenchyma without bone association or tumor manifestation at other locations. Three illustrative cases highlight the diversity of the clinical presentation of cerebral osteosarcoma: a 22-year-old man with multiple brain metastases following late pulmonary relapse of an osteosarcoma of the tibia, a 31-year-old woman with an osteosarcoma of the left anterior cranial fossa arising from the skull base, and a 78-year-old man presenting with primary osteogenic sarcoma of the left frontal cerebral hemisphere. According to the current literature, 10-15% of all osteosarcoma patients experiencing relapse may beat risk for central nervous system metastases. To the authors' best knowledge, there are 11 cases of primary intracerebral or meningeal osteogenic sarcoma, including this case report, without any skeletal attachment.

Adult↗

PubMedDate not supplied

In vitro excystation of Spironucleus muris.

In vitro excystation of Spironucleus muris cysts, purified by sequential sucrose and Percoll gradients from mouse feces, was studied. Three in vitro excystation procedures, used for Giardia, were assessed to determine the most useful method. Excystation was monitored by light microscopy and subsequently characterized by transmission and scanning electron microscopy. Spironucleus muris excysted routinely at a level greater than 90% when induced in Hanks' balanced salt solution containing sodium bicarbonate at pH 2.0 and transferred to Tyrodes' salt solution as an excystation medium. Similarly, high rates of excystation were recorded after induction of S. muris cysts in 0.1 M potassium phosphate buffer (pH 7.0) with sodium bicarbonate and excystation in trypticase-yeast extract-iron medium (TYI medium) or phosphate-buffered saline. A lower rate and percentage of excystation were observed after induction of S. muris cysts in an aqueous hydrochloric acid solution (pH 2.0) followed by excystation in TYI medium. All excystation methods produced extremely active S. muris trophozoites with normal morphology. Nonexcysting S. muris cysts have a wall composed of an outer fibrous and an inner membranous portion. Following induction, numerous vesicles appeared in the peritrophic space. Excystation began by the cyst wall opening at one pole, and the anterior part of the trophozoite protruding from the cyst wall. The trophozoite emerged progressively from the cyst wall and the empty cyst wall appeared to collapse. Excysted trophozoites exhibited normal morphological features of S. muris trophozoites isolated from the mouse intestine.

Animals↗

PubMedDate not supplied

Indications and results of the multichannel cochlear implant.

In the case of total deafness, the multichannel cochlear implant prosthesis constitutes a substantial improvement. It allows known words to be recognized without lip reading, with a great percentage of good responses. Clinical and phoniatric results are reported in 21 cases of patients with implants.

Acoustic Stimulation↗

PubMedDate not supplied

Auditory brainstem potentials in man evoked by electrical stimulation of the round window.

In normal subjects, round-window electrical stimulation provides a sound sensation and supplies brainstem-evoked responses whose form is just the same of those evoked by sound stimulation. This electrical stimulation also provides a sound sensation in more than 90% of cases of total deafness, which means that at least a few auditory nerve fibres are still present. Thus, this test is indispensable when considering surgical rehabilitation with a multichannel cochlear implant. The diagram of this response to an electrical stimulus differs completely in the case of total deafness and in normal subjects. The correlation between the form of these diagrams and the supposed etiology of the deafness is not significant.

Acoustic Stimulation↗

PubMedDate not supplied

Transcutaneous electrotherapy for severe tinnitus.

In about a third of cases of severe tinnitus, transcutaneous stimulation for a few minutes by means of electric square waves gives substantial improvement. This very simple treatment must be repeated two or three times to achieve success. If an obvious improvement is not obtained after two or three attempts, failure must be considered as certain. The parameters of these stimulations are described and clinical results are reported. The mechanism of the improvement is uncertain.

Electric Stimulation Therapy↗

PubMedDate not supplied

The effect of the acoustic nerve chronic electric stimulation upon the guinea pig cochlear nucleus development.

14 newborn guinea pigs have been deafened three days after birth by bilateral destruction of the organ of Corti, and among them 8 have been supplied with a chronic auditory electric stimulation by means of an intracochlear implanted electrode. The histological study and the anatomical reconstructions of these animals' cochlear nuclei demonstrate that this chronic stimulation prevents, at least partially, these auditory pathway medullary formations from atrophy due to the cochlear destruction.

Animals↗

PubMedDate not supplied

Study of the mechanism of vocal fold vibration during phonation.

The precise mechanism of vocal fold vibrations during phonation is not well known. At present it is impossible to say whether this movement is active or passive. Since the studies of MacLeod & Louis Sylvestre, we know that the vocal muscle is asynchronous and, so, can have a fast oscillatory movement induced by a continuous depolarization of the muscular fibre membranes. Thus, we believe at present that the glottic opening can be merely passive and that the closing can be both passive and active through a myogenic mechanism. The purpose of this work was to try to establish whether this concept is right, by recording simultaneously the aerodynamic forces acting upon the vocal folds and their acceleration during phonation. This acceleration represents the forces applied to the vocal folds as a function of time. By comparing the temporal evolution of the two forces we can assert that glottic opening is a passive movement. This protocol does not allow us to know if closure is due solely to the elastic retractive force, or also to a muscular, active force such as myogenic rhythm. To answer this question we must use another protocol.

Acceleration↗