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C Lee

Publications and source records attributed to C Lee.

At least 703 records · Page 39Linked to original sources
PubMed1992

Localization of the human CYP17 gene (cytochrome P450(17 alpha)) to 10q24.3 by fluorescence in situ hybridization and simultaneous chromosome banding.

The gene for human P450(17 alpha) (CYP17) was previously mapped to chromosome 10 through analysis of somatic cell hybrids. Using a modified procedure of fluorescence in situ hybridization, this gene has now been visualized on simultaneously banded chromosomes and localized to a specific subband of chromosome 10 at q24.3. This precise assignment may facilitate the understanding of the molecular basis of 17 alpha-hydroxylase/17,20-lyase deficiency and the evolution of the CYP superfamily of genes.

Chromosome Banding↗
PubMed1992

Mapping of 50 cosmid clones isolated from a flow-sorted human X chromosome library by fluorescence in situ hybridization.

Fifty cosmids have been mapped to metaphase chromosomes by fluorescence in situ hybridization under conditions that suppress signals from repetitive DNA sequences. The cosmid clones were isolated from a flow-sorted human X chromosome library. Thirty-eight of the clones were localized to chromosome X and 12 to autosomes such as chromosomes 3, 7, 8, 14, and 17. Although most of the cosmids mapped to the X chromosome appeared to be scattered along both the short and long arms, 10 cosmids were localized to the centromeric region of the chromosome. Southern blot analysis revealed that only two of these clones hybridized to probe pXBR-1, which detects the DXZ1 locus. In addition, 4 out of 5 cosmids mapped on chromosome 8 also localized on the centromeric region. While localization of X-specific cosmids will facilitate the physical mapping of the human X chromosome, cosmids mapped to the centromeric regions of chromosomes X and 8 should be especially useful for studying the structure and organization of these regions.

Blotting, Southern↗
PubMed1992

Effects of protein kinase inhibitors on pig oocyte maturation in vitro.

Normal oocyte maturation depends on signal transmission between granulosa cells and the oocyte. We have analysed the effects of inhibiting (I) cyclic AMP-dependent protein kinase (protein kinase A, PK-A), (II) Ca2+/phospholipid-dependent protein kinase (protein kinase C, PK-C) and (III) calmodulin (CaM) on pig oocyte maturation in vitro, protein synthesis and phosphorylation. The inhibition of PK-A using a specific inhibitor H8, decreased the maturation rate (rate of germinal vesicle breakdown, GVBD) of cumulus-enclosed pig oocytes in a dose-dependent manner by approximately 12%, reaching a plateau at 100 microM. The inhibition of PK-C with H7, an inhibitor with some side-effects on PK-A, decreased the maturation rate of cumulus-enclosed oocytes in a dose-dependent manner to a maximum of 20% at a concentration of 100 microM. The calmodulin antagonist W7 up to a concentration of 200 microM had no effects on maturation of cumulus-enclosed pig oocytes. None of the inhibitors (H7, H8 and W7) altered the patterns of protein synthesis of either pig oocytes and cumulus cells after maturation in vitro. Oocyte phosphoprotein patterns were, however, clearly changed by W7. Cumulus cell protein phosphorylation patterns were changed by all 3 agents. Since inhibition of cyclic AMP and Ca2+ phospholipid pathways by PK-A and PK-C blocking chemicals affected only a limited proportion of oocytes (12 and 20%, respectively) and inhibition of Ca2+ binding to CaM was without effect on oocyte maturation, we conclude that these pathways modulate rather than regulate oocyte maturation in the pig.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1992

Use of the Terumo SteriCell for the processing of bone marrow and peripheral blood stem cells.

The SteriCell cell processing instrument is a good choice for a stem cell processing laboratory that is of sufficient size that they cannot share an apheresis machine with the blood bank. It is a laboratory instrument, with no facility for patient connection. Because of its minimal size and weight, it is easily stored in a cramped laboratory. Its automated programs are appropriate for processing of bone marrow and peripheral blood stem cells, and it is quite easy to learn how to use (in our laboratory, most individuals have been completely facile with the SteriCell after fewer than six processings). Based on reported results from other instruments, the SteriCell provides cell yields that are comparable to competing instruments. Service (provided by Haemonetics) has been satisfactory, and support from Terumo has been excellent. We can recommend this instrument to any other laboratory.

Automation↗
PubMed1992

Redesigning, implementing and integrating Escherichia coli genome software tools with an object-oriented database system.

This paper reports our exploratory work to redesign, implement and integrate a collection of genome software tools with an object-oriented database system. Our software tools deal with genome data from Escherichia coli K-12, a bacterium that has been studied intensively and provides richer data sets than any other living organism. The object-oriented DBMS used for the integration is ONTOS, a commercial object-oriented system from Ontologic Inc. This redesign and implementation task was performed in two steps. First, C programs were converted into C++, and then the C++ version programs were modified and integrated with an object-oriented modeling of the data to form an ONTOS database application. The first step helps us develop a conceptual view for a DBMS-independent object-oriented construct. The second step elucidates what additional DBMS-dependent modification steps are needed to provide persistency to the objects. Examples are included to illustrate steps of the redesign and implementation. Overall, the outcome of this project demonstrates that programs and data can be successfully integrated with an object-oriented database, while providing the objects with persistency and shareability. This paper includes discussions using concrete examples on what advantage the object-oriented database approach provides over the relational database approach.

Base Sequence↗
PubMed1992

Recovery of cognitive functions after anaesthesia with desflurane or isoflurane and nitrous oxide.

We studied recovery in 25 adult patients, ASA I, undergoing elective orthopaedic procedures after anaesthesia with 0.65 MAC desflurane (n = 16) or isoflurane (n = 9) with 60% nitrous oxide in oxygen. Early emergence from anaesthesia was assessed in the operating room by measuring time to spontaneous movement, cough, response to painful pinch, tracheal extubation, opening of the eyes and stating correct age, name and body parts. The return of cognitive functions in the late recovery phase was assessed in the post-anaesthesia care unit (PACU) by post-anaesthesia recovery scores (PARS), the Trieger dot test (TDT), and the digit substitution test (DST). In the early recovery phase, time to tracheal extubation, opening eyes, telling correct name, age and body parts occurred significantly faster in the desflurane group than in the isoflurane group (P < 0.05). The mean "triple orientation" time (to name, age, body parts) was 10.9 (SEM 0.9) min for desflurane, compared with 18.6 (2.5) min for isoflurane (P < 0.01). In the late recovery phase, desflurane patients had significantly greater PARS, more correct responses to the DST and fewer error responses to the TDT. Recovery times were not increased by increased duration of desflurane anaesthesia. The desflurane patients showed no delirium, minimal sedation and less shivering during the entire postoperative course. We conclude that desflurane anaesthesia was superior to isoflurane anaesthesia, not only in emergence, but also in the recovery of cognitive functions.

Adolescent↗
PubMed1992

Successful treatment of disseminated nocardiosis complicated by cerebral abscess with ceftriaxone and amikacin: case report.

We report the case of an 85-year-old female patient who suffered from disseminated Nocardia asteroides infection complicated by a cerebral abscess. Treatment with amikacin for 2 weeks and ceftriaxone for 6 weeks led to complete recovery, and there was no recurrence of disease over a follow-up period of 12 months after therapy. The use of ceftriaxone in combination with amikacin might significantly shorten the duration of treatment for patients with disseminated nocardiosis. This combination of antibiotics merits further investigation with use of a larger sample of patients.

Aged↗
PubMed1992

Induction of specific gelatinolytic proteinases in the lateral prostate of rats by ectopic pituitary grafts.

Activities of plasminogen activator (PA) and gelatinolytic proteinase in the ventral, lateral, and dorsal lobes of the prostate were examined in rats with hyperprolactinemia, which was induced by implantation of ectopic pituitary grafts under the renal capsule. Weight and total DNA content of the lateral lobe increased significantly in rats receiving two pituitary glands as compared with values for the initial untreated group and the muscle-implanted control animals. No change in specific activity of PA was observed in any prostatic lobe for animals of different treatment groups. However, there was a lateral lobe-specific induction of gelatinolytic proteinase activity in pituitary-grafted rats. Two Ca(2+)-independent proteinase activities of approximately 26-28 and 88 kDa, and three calcium-sensitive proteinase activities of 59, 64, and 76 kDa were found in zymograms of lateral prostate extracts of the untreated initial group and the muscle-grafted control. The lateral prostate proteinase pattern of pituitary-grafted animals demonstrated intense activities of approximately 51, 53, 64, 76, and 135 kDa as well as weaker activities of 40, 43, 59, 85, 93, 105, and 125 kDa. Many of these proteinase activities were present in the secretion of the lateral prostate of the untreated initial controls, suggesting that hyperprolactinemia promotes secretion in the lateral prostate. Those proteinase activities that were not in the secretion were probably of intracellular origin and may play a role in cellular remodeling. Castration resulted in a decrease in activities of these proteinases, and this decrease was observed whether the pituitary grafts were retained or removed.

Animals↗
PubMed1992

Mammary gland differentiation in hypophysectomized, pregnant mice treated with corticosterone and thyroxine.

Swiss Webster mice were hypophysectomized or sham-operated on Day 11 of pregnancy. The animals were fitted s.c. with osmotic minipumps containing either corticosterone (B) dissolved in Molecusol (Pharmatec, Alachua, FL) or the vehicle alone immediately after they were hypophysectomized. Animals in some of the experimental groups also received thyroxine (T4) in their drinking water. The mice were killed on Day 18 of gestation, and mammary tissue was homogenized and extracted for assessment of DNA, RNA, alpha-lactalbumin, and alpha-casein. Serum was assayed for placental lactogen-I (PL-I), and placental lactogen-II (PL-II), B, and T4. The concentration of PL-II in serum was elevated in the hypophysectomized mice, whereas the PL-I concentration did not differ among experimental groups. Hypophysectomy decreased both T4 and B concentrations in serum, and administration of these hormones restored their serum concentrations to normal or, in some cases, somewhat higher than normal levels. Hypophysectomy reduced the total RNA content and RNA/DNA ratio of the mammary gland, but treatment with B alone or with B and T4 restored RNA levels to those of sham-operated animals. T4 alone was ineffective in restoring RNA levels. Sham-operated animals that received hormonal treatment (B and T4) had the highest levels of RNA in the mammary tissue. Hypophysectomized animals had reduced content and concentration of alpha-lactalbumin in the mammary gland as compared to all other experimental groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

The influence of propofol with and without nitrous oxide on cerebral blood flow velocity and CO2 reactivity in humans.

The cerebrovascular response to CO2 has been reported to be preserved during propofol anesthesia, but no comparison with awake control values has been made, and the additional influence of N2O has not been investigated. Using the noninvasive technique of transcranial Doppler ultrasonography, this study investigated the cerebrovascular response to varying levels of PaCO2 while awake and during anesthesia with propofol and propofol/N2O. Seven adults without systemic diseases undergoing nonneurologic surgery were studied. A pulsed-wave Doppler monitor was used to measure the mean middle cerebral artery flow velocity (Vmca) during varying levels of PaCO2 (25-55 mmHg) under the following conditions: 1) awake; 2) propofol 2.5 mg.kg-1 bolus followed by continuous infusion of 150 micrograms.kg-1.min-1; and 3) propofol as in the condition above plus 70% N2O. During the awake study condition, hypocapnia was induced by voluntary hyperventilation, and hypercapnia was induced with rebreathing of 7% CO2 in a closed circuit. During the anesthetized study conditions, hypocapnia and hypercapnia were induced by adjustment of minute ventilation. A minimum of five to six simultaneous Vmca and PaCO2 measurements were obtained under each of the study conditions. Systemic blood pressure was monitored via a radial arterial catheter, and phenylephrine was administered if mean arterial blood pressure decreased below 60 mmHg (phenylephrine was used in three of five patients in the propofol-N2O group). Linear regression and analysis of covariance were used for statistical analysis of Vmca-PaCO2 relationships.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

The role and limitations of computed tomographic scanning in the evaluation of cervical trauma.

We retrospectively reviewed the medical records, plain films, CT scans and complex-motion tomographic studies (TOMOS) of 216 consecutive patients with cervical injuries to determine the uses and limitations of CT in the evaluation of cervical trauma and the indications, if any, for the continued use of TOMOS in evaluating cervical trauma. There were 453 fractures and 104 subluxations or dislocations of the cervical spine in the 216 patients. Plain films detected 58% (262 of 453) of the fractures and 93% (97 of 104) of the subluxations and dislocations; and 94% (202 of 216) of the patients with abnormalities were identified. Computed tomographic scans detected 90% (406 of 453) of the fractures and 54% (56 of 104) of the subluxations and dislocations; 92% (198 of 216) of the patients with abnormalities were identified. Most of the abnormalities missed on the CT scans involved the dens, C-6, and C-7, and were oriented in the axial plane. Although CT scanning was better than plain films in detecting most types of cervical fractures, plain films were better than CT for detecting fractures of the vertebral body, dens, and spinous processes, and significantly better than CT in detecting subluxation and dislocation. When plain films and CT scans were combined they identified 98% (443 of 453) of the fractures and 99% (103 of 104) of the subluxations and dislocations; 100% (216 of 216) of the patients with abnormalities were identified. In the 20 patients who underwent both CT scanning and TOMOS, TOMOS detected more fractures, subluxations, and dislocations than CT scanning. Complex-motion tomographic studies detected atlanto-occipital dislocation and subluxation of the vertebral bodies and fractures of the spinous processes, lateral masses, articular processes, vertebral bodies, and dens better than CT scanning. Although the more routine use of CT scanning in evaluating cervical trauma should increase the detection of cervical abnormalities to near 100%, TOMOS remain the gold standard of diagnosis for atlanto-occipital dislocation, subluxation of the vertebral bodies, and fractures of the lateral masses, articular processes, vertebral bodies, and dens.

Adolescent↗
PubMed1992

Neutrophil localization following reperfusion of ischemic skin flaps.

A swine model of island latissimus dorsi myocutaneous and buttock cutaneous flaps was used to examine neutrophil localization and flap survival after 6 hours of global ischemia followed by 24 hours of reperfusion. Radioactivity from autotransfused neutrophils labeled with indium-111 enabled their localization. Radioactivity in ischemic latissimus dorsi flaps was increased by 101 +/- 30 percent over contralateral control latissimus dorsi flaps (n = 6, p = 0.01). Radioactivity in ischemic buttock flaps was increased by 142 +/- 40 percent over contralateral control buttock flaps (n = 6, p = 0.008). Despite increased neutrophil localization to ischemic flaps, the magnitude of tissue radioactivity failed to provide sufficient information to predict ischemic injury as measured by flap survival and tissue water content.

Analysis of Variance↗
PubMed1992

Altered neutrophil function following reperfusion of an ischemic myocutaneous flap.

The neutrophil has been implicated as a source of oxygen free radicals provoking the reperfusion injury in various ischemic organs. This provided the motivation to explore the pathophysiologic role of the neutrophil in a swine model of postischemic latissimus dorsi myocutaneous flaps. Neutrophil function, neutrophil sequestration, and the anatomic distribution of muscle injury were estimated following a 6- to 8-hour global ischemic insult. Neutrophil function as measured by phorbol myristate acetate-stimulated superoxide production was found to be enhanced on reperfusion of ischemic flaps (n = 17). Neutrophil sequestration estimated from the arterial-venous difference of flap blood (n = 12) demonstrated that postischemic flaps more avidly sequester neutrophils than nonischemic flaps. The anatomic distribution of muscle injury (n = 7) was predominantly localized to the proximal portion of the ischemic flap. The enhanced functional response exhibited by neutrophils reperfusing an ischemic myocutaneous flap supports an active neutrophil role in the mediation of reperfusion injury.

Analysis of Variance↗
PubMed1992

Use of an oligonucleotide probe to detect Vibrio parahaemolyticus in artificially contaminated oysters.

A 26-mer oligonucleotide specific to Vibrio parahaemolyticus was synthesized from a 1,275-bp thermostable direct hemolysin (tdh) gene. This oligonucleotide probe specifically reacted with DNA from 89 of 95 V. parahaemolyticus isolates but not with DNA from other vibrios or other enteric and nonenteric organisms (n = 48). The probe hybridized with Southern blots of 0.5-kb HindIII-restricted chromosomal DNA fragments from all but five V. parahaemolyticus test isolates. The probe could be used to directly identify V. parahaemolyticus in artificially contaminated food without an isolation step.

Animals↗
PubMed1992

Acuity-sensitivity trade-offs of X and Y cells in the cat lateral geniculate complex: role of the medial interlaminar nucleus in scotopic vision.

1. The cat medial interlaminar nucleus (MIN) receives inputs almost exclusively from tapetal retina, suggesting that the MIN has a special role in dim-light vision. In this study we compared the sensitivities of cells in the MIN with those in layers A and magnocellular C of the lateral geniculate nucleus (LGNd), using drifting sinusoidal gratings to determine contrast thresholds as a function of spatial frequency and retinal adaptation level over the entire scotopic range. 2. About one-half of the cells recorded in the MIN and layer A had brisk responses that could be nulled by properly positioned, counterphased sinusoidal gratings, and were classified as X cells. The rest of the cells in the MIN and layer A, as well as all cells recorded in layer C, were Y cells. 3. MIN cells had higher contrast sensitivity than layer A cells for low spatial frequencies (0.15 cycles/deg and below) over a wide range of adaptation levels, both overall and for separate comparisons within X or Y cells. Layer C Y cells were intermediate in sensitivity between MIN and layer A Y cells. For low spatial frequencies, Y cells as a group were more sensitive than X cells, whereas the reverse was true for high spatial frequencies. 4. These data enable one to determine the lowest adaptation level at which stimuli of a given contrast can be detected for a given structure. At the lowest spatial frequencies, the MIN can function at adaptation levels approximately 1 log unit below layer A, averaged over all stimulus contrasts. In contrast, the tapetum lowers luminance threshold by at most 0.16 log unit. 5. For scotopic conditions and eccentricities within 15 degrees of the area centralis, contrast sensitivity decreases with eccentricity for low spatial frequencies and remains flat or slightly increases for high spatial frequencies. This relationship, which is opposite to that found for photopic vision, is strongest for MIN Y cells. 6. These data support the hypothesis that the retinal conflict between sensitivity and acuity is ameliorated in the CNS through separate thalamic relays with different degrees of afferent convergence. MIN cells have higher luminance sensitivity than layer A cells, but at the expense of acuity. Layer C appears to occupy an intermediate position in this trade-off.

Animals↗
PubMed1992

The calcium second messenger system in bipolar disorders: data supporting new research directions.

Studies of aberrations in second messenger function may help to elucidate some of the multiple complex neurobiological alterations in bipolar affective disorders. The phosphatidylinositol and calcium ion (Ca2+) second messengers are of particular interest because of evidence of hyperactivity of these signaling mechanisms in both mania and bipolar depression and of their normalization by lithium and other mood-stabilizing treatments. Because the intracellular Ca2+ signal has a biphasic action, a single aberration could explain diverse clinical manifestations of the same illness, and a single action on the messenger could explain the biphasic actions of many treatments for bipolar disorders.

Bipolar Disorder↗