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Wang C, Leung A, Tsoi WL, Leung J, Ng V, Lee KF, Chan SY. Evaluation of human sperm hyperactivated motility and its relationship with the zona-free hamster oocyte sperm penetration assay. JOURNAL OF ANDROLOGY 1991; 12:253-7. [PMID: 1917691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The authors studied hyperactivated motility of human spermatozoa as a method of evaluating capacitation by examining its relationship to results of zona-free hamster oocyte sperm penetration assays (SPA) of semen samples from 50 men attending the infertility clinic. Hyperactivated motility was assessed in the seminal plasma and after swim-up preparation of spermatozoa at 1, 3, and 24 hours of incubation in capacitation media using a computer-assisted semen analysis system equipped with a hyperactivation module. Hyperactivated motility reached a peak at 1 hour and plateaued at 3 hours. The percentage of spermatozoa in seminal plasma with star-spin hyperactivated motility was significantly lower in the group showing no penetration in the SPA. The hyperactivated motility characteristics did not differ in the groups with positive or negative penetration. Correlation analysis failed to show any significant relationship between the hyperactivated motility parameters and SPA score. When the hyperactivated motility characteristics were compared in samples with normal and abnormal semen analyses, the total percentage of spermatozoa with hyperactivated motility and the percentage with star-spin at 3 hours were significantly lower in the group with abnormal semen analysis. The data indicate that lower hyperactivated motility of spermatozoa was found in patients with a score of zero for SPA and in patients with abnormal semen analysis. It was concluded that although no direct correlations were found between the results of SPA and hyperactivated motility, evaluating hyperactivated motility may still be useful as an early indicator of capacitation abnormalities of human spermatozoa not measured by SPA.
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Wang C, Leung A, Tsoi WL, Leung J, Ng V, Lee KF, Chan SY. Computer-assisted assessment of human sperm morphology: usefulness in predicting fertilizing capacity of human spermatozoa. Fertil Steril 1991; 55:989-93. [PMID: 2022276 DOI: 10.1016/s0015-0282(16)54311-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE The usefulness of sperm morphology to predict the outcome of human sperm fertilizing capacity was examined. DESIGN, SETTING, PATIENTS Semen samples from 50 male patients attending the infertility clinic of a tertiary referral institution were studied. MAIN OUTCOME MEASURES Sperm morphology was classified both by visual assessment and computer-assisted image analysis. In addition, morphometric analysis of the spermatozoa was measured by the morphologizer. Multivariate discriminant analysis was used to evaluate the usefulness of these morphology parameters for predicting the outcome of the zona-free hamster oocyte sperm penetration assay. RESULTS The manually derived percent of spermatozoa with normal and small head were selected to be of discriminating value in predicting the outcome of the zona-free hamster oocyte penetration test. The accuracy of correctly classifying the outcome of zona-free hamster oocyte penetration test by these two parameters in combination was 84%, whereas assessment of sperm morphology with morphometric analysis by the morphologizer selected a total of eight variables, which together predicted sperm fertilizing capacity with 74% accuracy. Addition of the morphologizer-derived parameters to those derived manually did not significantly improve the predictive value. CONCLUSION We conclude that the results of the zona-free hamster egg penetration test could be predicted using manual assessment of sperm morphology and computer-assisted morphometric analysis did not add further information.
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Wang C, Leung A, Tsoi WL, Leung J, Ng V, Lee KF, Chan SY. Computer-assisted assessment of human sperm morphology: comparison with visual assessment. Fertil Steril 1991; 55:983-8. [PMID: 2022275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE Sperm morphology classification was analyzed by the computer-assisted semen analysis equipped with the Morphologizer II (Cryo Resources Ltd., New York, NY) was compared with the traditional manual method. DESIGN, SETTING, PATIENTS Fifty stained semen smears from men attending the infertility clinic of a tertiary referral institution were studied. MAIN OUTCOME MEASURES Sperm head morphology was classified by the two methods into the following forms: normal, small oval, big oval, taper, and amorphous. RESULTS Overall, the classifications of mean percent normal, small, and amorphous head forms were similar in the two methods. However, the differences between paired values obtained by the two methods were highly variable (range from -20% to +20%). The large differences between the methods were related to the large coefficients of variations present when classifying abnormal sperm morphology even by the same experienced technician. Only the percent normal spermatozoa could be classified by both methods with acceptable precision. In contrast, the variations in the morphometric analyses between the different semen smears were very small. CONCLUSIONS There was no advantage of the morphologizer over the manual method in sperm morphology classification. The clinical value of morphometric parameters of spermatozoa has to be defined.
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Lee KF, Dyke CM, Wechsler AS. Theoretical considerations in the use of dynamic cardiomyoplasty to treat dilated cardiomyopathy. J Card Surg 1991; 6:119-23. [PMID: 1807493 DOI: 10.1111/jocs.1991.6.1s.119] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Clinical data describing the hemodynamic benefits of cardiomyoplasty are inconclusive, and there has not been any study detailing the mechanisms by which dynamic cardiomyoplasty may improve the functional and mechanical impairments of the failing heart. The left ventricle in dilated cardiomyopathy is characterized by increased end-diastolic volume, inadequate systolic myocardial wall thickening, increased wall stress, and decreased stroke volume. Based on experimental and preliminary clinical data, we propose that cardiac assistance by dynamic cardiomyoplasty is the consequence of enhanced volume translocation rather than increased potential for pressure generation. A small augmentation of dimensional shortening results in a large increment of stroke volume because of the enlarged resting chamber volume. Key geometric effects are enhanced systolic chamber shortening and increased wall thickening, resulting in a net decrease of myocardial wall stress. The contractile skeletal muscle may improve myocardial mechanics, and normalization of the afterload mismatch may be an important mechanism by which dynamic cardiomyoplasty augments cardiac output.
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Feun LG, Savaraj N, Lee YY, Landy H, Martinez-Prieto J, Charnsangavej C, Post JD, Lee KF, Wallace S, Bowen B. A pilot clinical and pharmacokinetic study of intracarotid cisplatin and bleomycin. SELECTIVE CANCER THERAPEUTICS 1991; 7:29-36. [PMID: 1718023 DOI: 10.1089/sct.1991.7.29] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Fifteen patients with progressive primary malignant or metastatic brain tumors were treated on a clinical and pharmacokinetic study with intracarotid cisplatin and bleomycin. Toxicity was tolerable and consisted mainly of nausea and vomiting. Neurologic toxicity included focal seizures (1), leukoencephalopathy (1), and motor weakness (1). Five patients had improvement in CT scans and four patients had stabilization of disease. Recommended dosage for future clinical trials are cisplatin 60 mg/m2 and bleomycin 100 units. Pharmacokinetics of intracarotid cisplatin revealed the jugular vein concentration was twice the peripheral vein level at the end of infusion. Cisplatin is a drug which has demonstrated in vitro activity against malignant gliomas (1). Clinical trials with intravenous administration of cisplatin has shown definite, although limited antitumor activity against primary brain tumors (2,3,4) and metastatic brain tumors (5,6). To enhance its antitumor effect, cisplatin has been administered by the intracarotid route (7,8,9). The results appear encouraging, but neurological and ophthalmological toxicity may occur (8). In our initial study with intracarotid cisplatin, 35 patients with malignant brain tumors (23 with primary brain tumors and 12 with brain metastases) progressing after cranial irradiation +/- chemotherapy were treated. Of 20 evaluable patients with primary tumors, 6 responded to therapy and 5 had stable disease. Five of 10 evaluable patients with brain metastases responded and 2 had stable disease. For responding primary brain tumor patients the median time to progression was 33 weeks. The recommended dose for intracarotid cisplatin was 60-75 mg/m2 administered every 3-4 weeks (7,8). Higher cisplatin doses produced more central neurological toxicity. There is limited data on the central nervous system pharmacology of cisplatin.(ABSTRACT TRUNCATED AT 250 WORDS)
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Rebeyka IM, Yeh T, Hanan SA, Borges MR, Lee KF, Tuchy GE, Abd-Elfattah AS, Wechsler AS. Altered contractile response in neonatal myocardium to citrate-phosphate-dextrose infusion. Circulation 1990; 82:IV367-70. [PMID: 2171810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The clinical use of citrate-phosphate-dextrose during blood-product transfusion is known to affect ionized calcium levels and can result in depression of myocardial contractility. The immature heart appears to have an intrinsic reduction in contractile state compared with the adult heart and may be more dependent on transsarcolemmal calcium flux for regulation of contraction. The myocardial contractile response to citrate infusion was compared in neonatal and adult rabbit hearts using clinically comparable citrate-phosphate-dextrose concentrations. Isovolumic left ventricular pressures were monitored in an isolated, crystalloid-perfused heart model before, during, and after 15 minutes of citrate-phosphate-dextrose infusion. Developed pressure decreased 42.1 +/- 4.9% from control within 1 minute in the neonatal group versus 24.3 +/- 4.3% in the adult group (p less than 0.02). The effect on diastolic function was paradoxical in the neonate with a 43.1 +/- 11.9% increase in end-diastolic pressure compared with a 9.7 +/- 7.8% decrease in the adult (p less than 0.01). These results indicate that the neonatal heart appears more sensitive to the myocardial effects of citrate infusion with impairment of both systolic and diastolic function. The decreased ventricular compliance in the neonate with citrate-phosphate-dextrose suggests that the myocardial effects may not be simply due to changes in ionized calcium concentration.
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Rebeyka IM, Hanan SA, Borges MR, Lee KF, Yeh T, Tuchy GE, Abd-Elfattah AS, Williams WG, Wechsler AS. Rapid cooling contracture of the myocardium. The adverse effect of prearrest cardiac hypothermia. J Thorac Cardiovasc Surg 1990; 100:240-9. [PMID: 2385121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Hypothermic total circulatory arrest for repair of congenital heart lesions in neonates requires a period of rapid core cooling on cardiopulmonary bypass during which the myocardium is also exposed to hypothermic perfusion. Myocardial hypothermia in the nonarrested state results in an increase in contractility due to elevation of intracellular calcium levels. This study was designed to test the hypothesis that rapid myocardial cooling before cardioplegic ischemic arrest results in damage, with impaired recovery during reperfusion. Two groups of 10 rabbit hearts were perfused on an isolated Langendorff apparatus. Group N (normothermia) was perfused at 37 degrees C before 2 hours of cardioplegic ischemic arrest at 10 degrees C. Group C (cooling) was perfused at 15 degrees C in the unarrested state for 20 minutes before the same cardioplegic arrest conditions as group N. Left ventricular isovolumic pressure measurements, biochemical measurements from right ventricular biopsy specimens, and ventricular necrosis as defined by tetrazolium staining were used to compare the groups at 30 and 60 minutes of normothermic reperfusion. Developed pressure at a constant volume was preserved in group N at 90.7 +/- 4.5 mm Hg versus 76.9 +/- 6.3 in group C after reperfusion (p less than 0.05). Diastolic compliance showed significant deterioration in group C, with marked elevation of diastolic pressure during reperfusion (group N = 6.8 +/- 2.5 mm Hg versus group C = 38.9 +/- 6.1 after reperfusion; p less than 0.001). Adenosine triphosphate levels were significantly higher in group N both at end-ischemia and after reperfusion versus group C (group N = 17.0 +/- 1.1 nmol/mg protein versus group C = 7.7 +/- 1.0 after reperfusion; p less than 0.001). Group N had 0.4% +/- 0.4% necrosis of ventricular mass versus 19.3% +/- 2.2% with prearrest cooling in group C (p less than 0.0001). These results indicate that, when combined with cardioplegic ischemic arrest, rapid myocardial cooling in the unarrested state results in significant damage. The mechanism may be related to the cytosolic calcium loading effect of hypothermia that is not relieved during the subsequent period of cardioplegic arrest. Although hypothermia is an essential component to ischemic preservation, rapid cooling contracture can adversely influence cardioplegic myocardial protection.
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Yeh T, Hanan SA, Johnson DE, Rebeyka IM, Abd-Elfattah AS, Lee KF, Wechsler AS. Superior myocardial preservation with modified UW solution after prolonged ischemia in the rat heart. Ann Thorac Surg 1990; 49:932-9. [PMID: 2369191 DOI: 10.1016/0003-4975(90)90869-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Cardiac transplantation remains constrained by poor graft tolerance of prolonged cold ischemia. University of Wisconsin solution has remarkably extended ischemic preservation in pancreas, kidney, and liver transplantation. To assess its efficacy in cardiac preservation, modified University of Wisconsin solution flush and storage were tested against St. Thomas' cardioplegia flush and normal saline solution storage after six hours of ischemia at 0 degrees C in 46 isolated rat hearts. After ischemia, groups were compared before and after reperfusion. After ischemia but before reperfusion, University of Wisconsin solution hearts had significantly less tissue water (3.8%), superior tissue sodium, potassium, calcium, and magnesium profiles, and elevated adenosine and inosine levels, and tended toward better histological preservation. After reperfusion, University of Wisconsin solution more effectively preserved left ventricular compliance (75% versus 35% of baseline), developed pressure (71% versus 45% of baseline), histological integrity, and tissue potassium and calcium profiles than St. Thomas' solution. The University of Wisconsin solution provided superior preservation of systolic and diastolic ventricular function, tissue histology, tissue water, and tissue electrolytes than did St. Thomas' cardioplegia and normal saline solution storage in this experimental model, and might result in improved graft tolerance of ischemia in clinical cardiac transplantation.
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Briggs FN, Lee KF, Feher JJ, Wechsler AS, Ohlendieck K, Campbell K. Ca-ATPase isozyme expression in sarcoplasmic reticulum is altered by chronic stimulation of skeletal muscle. FEBS Lett 1990; 259:269-72. [PMID: 2136731 DOI: 10.1016/0014-5793(90)80025-e] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Chronic stimulation of a predominantly fast skeletal muscle enhanced the expression of type I (slow muscle) Ca-ATPase and suppressed the expression of the type II (fast muscle) Ca-ATPase. Monoclonal antibodies IID8 and IIH11 against type I (slow) and type II (fast) isozymes respectively, were used to type the Ca-ATPases of the isolated SR (sarcoplasmic reticulum) by Western blots, and the Ca-ATPases of the muscle fibers by immunohistochemistry. Of the fibers from control muscles 80% stained for the type II isozyme and 20% for the type I isozyme. Following chronic stimulation all fibers stained for type I isozyme and none stained for type II isozyme. Ca-ATPase isozyme distribution in isolated SR confirmed this effect of chronic stimulation. The calcium uptake activities of homogenates of stimulated muscles were 22% of the control muscles. The Ca-ATPase and calcium-uptake activities of the isolated SR from stimulated muscles were, respectively, 32 and 45% of the control muscles.
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260
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Rosen JM, Bayna E, Lee KF. Analysis of milk protein gene expression in transgenic mice. MOLECULAR BIOLOGY & MEDICINE 1989; 6:501-9. [PMID: 2699509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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261
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Lee KF, Atiee SH, Henning SJ, Rosen JM. Relative contribution of promoter and intragenic sequences in the hormonal regulation of rat beta-casein transgenes. Mol Endocrinol 1989; 3:447-53. [PMID: 2747652 DOI: 10.1210/mend-3-3-447] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
In order to identify DNA sequences responsible for the regulation beta-casein gene expression, lines of transgenic mice bearing the entire rat beta-casein gene and two rat beta-casein promoter chloramphenicol acetyltransferase (CAT) fusion genes have been established. All three transgenes have been shown previously to be regulated in a tissue- and stage specific manner. To investigate the relative contribution of promoter and intragenic sequences in the hormonal regulation of the beta-casein gene, mammary explant cultures derived from these lines of mice have now been performed, and the effects of PRL and glucocorticoids on transgene as compared with endogenous beta-casein gene expression have been quantified. After the addition of PRL to cultures performed in the presence of insulin and glucocorticoids, a 25- to 40-fold induction of endogenous mouse beta-casein mRNA was observed after 48 hr. A comparable greater than 25-fold induction of transgene expression after PRL addition was observed in explant cultures derived from a line of mice expressing the entire rat beta-casein gene. In contrast, PRL addition elicited only a 1- to 4.5-fold increase in CAT activity in cultures derived from two lines of mice bearing casein-CAT fusion genes with either 524 or 2300 base pairs of 5'-flanking DNA. In the presence of insulin, glucocorticoid or PRL addition alone increased endogenous beta-casein gene expression 2- to 2.5-fold and 5- to 10-fold, respectively, but only a 1.2- to 2.5-fold induction of CAT activity was observed for each hormone.(ABSTRACT TRUNCATED AT 250 WORDS)
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Lee KF, Atiee SH, Rosen JM. Differential regulation of rat beta-casein-chloramphenicol acetyltransferase fusion gene expression in transgenic mice. Mol Cell Biol 1989; 9:560-5. [PMID: 2710117 PMCID: PMC362632 DOI: 10.1128/mcb.9.2.560-565.1989] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Previous studies in our laboratory have demonstrated the mammary-specific expression of the entire rat beta-casein gene with 3.5 kilobases (kb) of 5' and 3.0 kb of 3' DNA in transgenic mice (Lee et al., Nucleic Acids Res. 16:1027-1041, 1988). In an attempt to localize sequences that dictate this specificity, lines of transgenic mice carrying two different rat beta-casein promoter-bacterial chloramphenicol acetyltransferase (cat) fusion genes have been established. Twenty and eight lines of transgenic mice carrying two fusion genes containing either 2.3 or 0.5 kb, respectively, of 5'-flanking DNA of the rat beta-casein gene along with noncoding exon I and 0.5 kb of intron A were identified, most of which transmitted the transgenes to their offspring in a Mendelian pattern. CAT activity was detected predominantly in the lactating mammary gland of female transgenic mice but not in the male mammary fat pad. A several-hundred-fold variation in the level of cat expression was observed in the mammary gland of different lines of mice, presumably due to the site of integration of the transgenes. CAT activity was increased in the mammary gland during development from virgin to midpregnancy and lactation. Unexpectedly, the casein-cat transgenes were also expressed in the thymus of different lines of both male and female mice, in some cases at levels equivalent to those observed in the mammary gland, and in contrast to the mammary gland, CAT activity was decreased during pregnancy and lactation in the thymus. Thus, 0.5 kb of 5'-flanking DNA of the rat beta-casein gene along with noncoding exon I and 0.5 kb of intron A are sufficient to target bacterial cat gene expression to the mammary gland of lactating mice.
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Abstract
The "delta sign" is a triangular area of high density with a low-density center seen on contrast-enhanced computerized tomography (CT) scans in the location of the superior sagittal sinus. It indicates thrombosis of the sinus. The authors describe the "pseudodelta sign," which is similar but is seen on non-contrast-enhanced CT scans and which has a high correlation with hemorrhage secondary to acute head trauma.
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Mayer JS, Wainwright DJ, Yeakley JW, Lee KF, Harris JH, Kulkarni M. The role of three-dimensional computed tomography in the management of maxillofacial trauma. THE JOURNAL OF TRAUMA 1988; 28:1043-53. [PMID: 3398083 DOI: 10.1097/00005373-198807000-00022] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Open reduction and internal fixation of facial fractures demand a detailed understanding of the three-dimensional pattern of injury. This is difficult if not impossible to obtain with present radiographic methods. The purpose of this study was to define the role of three-dimensional computerized tomography (3DCT) in surgical management of facial fractures. The two-part investigation: 1) compared the diagnostic accuracy of 3DCT with conventional CT and plain film studies; and 2) examined the clinical usefulness of 3DCT to surgeons. Twenty-four acute trauma patients suspected of having facial fractures were examined radiographically with analysis of every facial bone and specific facial regions. Particular attention was directed to the course of the fracture lines and the number, size, and displacement of fracture fragments. The surgeons were then asked to conceptualize the reported and the personally observed radiographic information and document their impressions on preprinted diagrams of the facial skeleton. They also completed questionnaires designed to indicate whether patient management would be influenced by the 3DCT. The radiographic findings were correlated with intraoperative observations. The 3DCT provided superior definition of fracture lines (especially horizontal) and the extent of comminution was better appreciated. This additional information improved the surgeons' ability to plan placement of interfragmentary wires and/or plates. Surgeons were also able to more accurately predict those patients requiring immediate bone grafting. Large, life-size 3D images of the facial skeleton made intraoperative conceptualization of the injury pattern easier. The accuracy of the 3DCT images corroborated the intraoperative findings in all cases. The following conclusions are offered: 1) The diagnosis of most mandibular fractures can be made equally well with conventional and 3DCT techniques. 2) Improved diagnosis of fracture lines and the specific patterns of comminution in midface fractures is made possible with 3DCT. 3) If open reduction and internal fixation is the mode of treatment, 3DCT is desirable because the added information makes preoperative planning more accurate and thereby facilitates surgical intervention.
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Lee KF, DeMayo FJ, Atiee SH, Rosen JM. Tissue-specific expression of the rat beta-casein gene in transgenic mice. Nucleic Acids Res 1988; 16:1027-41. [PMID: 3344200 PMCID: PMC334735 DOI: 10.1093/nar/16.3.1027] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The rat beta-casein gene is a member of a small gene family, encoding the principal milk proteins. In order to understand the mechanisms by which its stage- and tissue-specific expression are regulated, initially, a 14 kb genomic clone containing the entire 7.5 kb rat beta-casein gene with 3.5 kb of 5' and 3.0 kb of 3' flanking DNA was microinjected into the germline of mice. Eight F0 transgenic mice were generated with copy numbers ranging from 1-10; five transmitted the transgene to their offspring in a Mendelian pattern. A specific RNase protection assay was developed to quantitate the level of expression of the rat beta-casein transgene as compared to the endogenous mouse beta-casein gene. Using this assay expression was demonstrated predominantly in the lactating mammary gland of transgenic mice at a level of 0.01-1% of the endogenous mouse beta-casein gene. The transgene employed the authentic transcription initiation site observed previously in the analogous rat beta-casein gene. In one line, a reduced level of expression of the transgene was also observed in the brain. The site of integration, therefore, plays an important role in influencing the level of expression of the transgene, but not its general pattern of tissue-specificity. The transgene appears to be developmentally-regulated in accordance with the endogenous mouse beta-casein gene. These lines of mice generated carrying the rat beta-casein transgene should provide useful models for studying the developmental and hormonal regulation of milk protein gene expression.
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Lee KF, Mandell J, Rankin JS, Muhlbaier LH, Wechsler AS. Immediate versus delayed coronary grafting after streptokinase treatment. Postoperative blood loss and clinical results. J Thorac Cardiovasc Surg 1988; 95:216-22. [PMID: 3257535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Of all patients with acute evolving myocardial infarction treated surgically at Duke University Medical Center between 1984 and 1986, 27 patients given high doses (greater than 1.5 million units) of streptokinase preoperatively were studied. Eleven patients who received streptokinase had coronary bypass grafting 12 hours after thrombolytic therapy (early hours), eight patients between 12 and 72 hours (delayed), and eight patients beyond 72 hours (late hours). Seventeen patients who underwent coronary bypass grafting within 6 hours of the onset of symptoms, without preoperative streptokinase, were included as control patients. Only the patients having early operation had significantly greater postoperative blood loss; postoperative use of red blood cells; fresh-frozen plasma; cryoprecipitate; prolonged postoperative prothrombin time; and prolonged partial thromboplastin time. Patients having delayed or late operations did not differ significantly from patients not receiving streptokinase. Only the interval between time of streptokinase administration and operation could account for the coagulopathy and the postoperative bleeding complications in the early group. Patients in the early group had a higher in-hospital mortality (27% versus 6% for the non-streptokinase group) and major noncardiac morbidity (36% versus 12% for the non-streptokinase group). Patients in the delayed and late groups had minimal postoperative complications and no mortality. Observations were not explained by differences in total ischemic time, number of angioplasty failures, or number of patients with cardiogenic shock between the early group and the non-streptokinase group. Postoperative bleeding and massive use of blood products seemed to be contributory factors: Two of three deaths in the patients having early operations were associated with clinical suspicion of tamponade. Patients undergoing coronary bypass grafting within 12 hours of streptokinase therapy appear to be a high-risk group in a more emergent, uncontrolled clinical setting and require aggressive monitoring and correction of coagulopathy.
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Kulkarni MV, Lee KF, McArdle CB, Yeakley JW, Haar FL. 1.5-T MR imaging of pituitary microadenomas: technical considerations and CT correlation. AJNR Am J Neuroradiol 1988; 9:5-11. [PMID: 3124586 PMCID: PMC8331541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Thirty-seven patients with suspected pituitary tumors were evaluated prospectively with MR imaging at 1.5 T. MR detected a microadenoma at its correct location in all eight patients who underwent transsphenoidal surgery, while CT showed a focal abnormality in the correct location in only four of the eight patients. In patients who were clinically and endocrinologically considered to harbor a microadenoma, MR detected a focal pituitary signal abnormality in 83% and CT demonstrated a focal density abnormality in 42%. Infundibular displacement, focal gland convexity, and sellar-floor abnormality were seen equally well with CT and MR. MR imaging protocol included sagittal T1-weighted spin-echo, coronal inversion-recovery, and coronal spin-echo or cardiac-gated spin-echo images. Although inversion-recovery images were superior in detecting focal pituitary lesions, some microadenomas were better seen on T2-weighted images. Cardiac-gated spin-echo images showed focal pituitary lesions better than ungated images did. Our technique demonstrates MR's superior sensitivity to CT in detecting a pituitary microadenoma.
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268
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Kulkarni MV, McArdle CB, Kopanicky D, Miner M, Cotler HB, Lee KF, Harris JH. Acute spinal cord injury: MR imaging at 1.5 T. Radiology 1987; 164:837-43. [PMID: 3615885 DOI: 10.1148/radiology.164.3.3615885] [Citation(s) in RCA: 262] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Thirty-seven magnetic resonance (MR) imaging studies were performed with a 1.5-T magnet and surface coils in 27 patients with suspected spinal cord injuries. Imaging was performed 1 day to 6 weeks after injury. Cord abnormalities were seen with MR in 19 patients, while skeletal and/or ligamentous injuries were seen in 21 (78%). Three types of MR signal patterns were seen in association with cord injuries. Acute intraspinal hemorrhage was seen in five patients with cord injuries and demonstrated decreased signal intensity on T2-weighted images obtained within 24 hours of injury. Cord edema and contusion had high signal intensity on T2-weighted images and were observed in 12 cases with cord injury. Neurologic recovery, determined in 16 patients, was insignificant in patients with intraspinal hemorrhage; however, patients with cord edema or contusion recovered significant neurologic function. MR at 1.5 T is extremely useful in the diagnosis of acute cord injury and also demonstrates potential in predicting neurologic recovery.
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Lee KF, Wagner LK, Lee YE, Suh JH, Lee SR. The impact-absorbing effects of facial fractures in closed-head injuries. An analysis of 210 patients. J Neurosurg 1987; 66:542-7. [PMID: 3559719 DOI: 10.3171/jns.1987.66.4.0542] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A series of 210 patients with facial fractures sufficiently severe to require cranial computerized tomography (CT) to evaluate suspected closed-head injury (CHI) was studied. The injuries were separated into five grades of severity based on neurological examination, including cranial CT. The injuries were also grouped into three categories based on facial regional involvement, using chi-square contingency table analysis. The data demonstrated that patients with upper facial fractures were at greatest risk for serious CHI. Injuries to both the mandibular and the midfacial regions with no upper facial involvement more frequently resulted in mild CHI with a modest likelihood of no neurological deficits. Trauma to only the mandibular region or to only the midfacial region was least likely to involve CHI.
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Van Tassel P, Yeakley JW, Lee KF. Cerebellar calcification in central neurofibromatosis: CT in two cases. AJNR Am J Neuroradiol 1987; 8:913-5. [PMID: 3118684 PMCID: PMC8334496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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271
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Abstract
Craniocerebral gunshot wounds are a significant cause of injury and death in the United States. However, despite reports of occasional unexpectedly favorable outcome in surgically treated patients, these injuries have been viewed pessimistically and indeed have generally been excluded from modern studies of head injuries, which have concentrated on closed head injuries. A review of 143 victims of craniocerebral gunshot wounds admitted to Hermann Hospital, Houston, Texas, during a recent 30-month period confirmed that a few apparently neurologically devastated patients can be saved. A detailed analysis of these patients, including demographic details, general and neurological condition, anatomic injuries, laboratory findings, surgical care, neurological course, and neurological and functional outcome follows. The helpfulness of early resuscitation and appropriate criteria for surgery need to be studied using historic or randomized controls.
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272
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273
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Abstract
A retrospective study of 100 cerebral computed tomography scans interpreted as displaying subarachnoid hemorrhage was undertaken to determine the frequency of blood in the interpeduncular fossa as a useful radiographic sign. The results indicate that the interpeduncular fossa sign is second only to blood in the Sylvian fissure-circular sulcus area as a reliable indicator of subarachnoid hemorrhage on CT scans.
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274
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Yeakley JW, Lee KF, Patchell LL. Modified scalp vein needle for arterial puncture in infants. AJNR Am J Neuroradiol 1986; 7:517-8. [PMID: 3085457 PMCID: PMC8331344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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275
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Tang RA, Winn TL, Lee KF, Marroquin G, Patchell L, Yeakley JW. Unilateral pupillary distortion: a case report. JOURNAL OF CLINICAL NEURO-OPHTHALMOLOGY 1985; 5:105-8. [PMID: 2947912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A 29-year-old white man who complained of episodic pupillary distortion in his right eye brought on by strenuous exercise was found to have a segmental Horner's syndrome in association with a hypoplastic internal carotid artery.
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