1301
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Glossip N, Hu R. Clinical accuracy in image guided surgery. Clin Neurol Neurosurg 1997. [DOI: 10.1016/s0303-8467(97)82254-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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1302
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Liu B, Hu R, Deng J. Characterization of immobilization of an enzyme in a modified Y zeolite matrix and its application to an amperometric glucose biosensor. Anal Chem 1997; 69:2343-8. [PMID: 9212705 DOI: 10.1021/ac960930u] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A new approach to construct an amperometric biosensor is described. Without using bovine serum albumin-glutaraldehyde, glucose oxidase (GOx) was immobilized on a dealuminized Y zeolite (DAY)-modified platinum electrode to construct a glucose sensor. The large specific surface area of the zeolite substrate resulted in high enzyme loading. The immobilized GOx in this manner was stable and could maintain its high activity for at least 3 months. The interactions between the zeolite and the enzyme were investigated by means of Fourier transform infrared spectra, and the pore distribution and the surface acid property of DAY were preliminarily studied. The results showed that the hydrophilic property and the existing mesopores of DAY played important roles in the enzyme immobilization. This resulting biosensor exhibited good reproducibility and selectivity, owing to the uniform pore structure and unique ion-exchange property of the zeolite. The biosensor responded rapidly to glucose in the linear range from 2.0 x 10(-6) to 3.0 x 10(-3) M, with a detection limit of 0.5 microM.
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Affiliation(s)
- B Liu
- Department of Chemistry, Fuden University, Shanghai, People's Republic of China
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1303
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Yang J, Xing T, Yao X, Hu R. [Relationship of C-erbB-2 oncogene overexpression to estrogen progesterone receptors in brease cancer and its prognostic significance]. Hua Xi Yi Ke Da Xue Xue Bao 1997; 28:214-7. [PMID: 10683938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
In order to understand the relationship of C-erbB-2 oncogene overexpression to ER and PR in breast cancer and its prognostic significance, we examined overexpression of C-erbB-2 oncogene in 106 breast carcinomas by using immunohistochemical techniques (LSAB). The results showed that the positive rate of C-erbB-2 overexpression was 63.21% (67/106). The overexpression of C-erbB-2 oncogene related negatively with survival. 81.63% of the cases with overexpression of C-erbB-2 oncogene survived < or = 5 years and 34.29% survived > 10 years. There were significant associations of C-erbB-2 overexpression with advance clinical stage, high histological grade, and positive axillary node status in breast cancers. Negative relationship between hormone receptors and C-erbB-2 oncogene. All of these findings suggested that overexpression of C-erbB-2 oncogene might be an important prognostic factor and the detection of C-erbB-2 oncogene might be arranged as a regular pathological examination in the cases of breast cancer.
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Affiliation(s)
- J Yang
- Department of General Surgery, First Affiliated Hospital, Chengdu
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1304
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1305
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Yuan K, Hu R, Zhen X, Jing L, Cao Z. [Determination of oridonin in Rabdosia rubescens by TLC-scanning method]. Zhong Yao Cai 1997; 20:242-3. [PMID: 12572464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
We have determingd the content of oridonin in Rabdosia rubescens Hemsl by TLC-scenning method. This method is proved to be simple, fast, precise and sensitive, and the result is stable, repetition property is good. Its rate of recovery is as high as 98.03 percent.
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Affiliation(s)
- K Yuan
- Henan College of Traditional Chinese Medicine, Zhengzou 450003
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1306
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Abstract
STUDY DESIGN In vitro and in vivo assessment of the accuracy of devices proposed for tracking spine motion during surgery; in vivo assessment of vertebral motion during spine surgery. OBJECTIVES 1) To quantify the accuracy of newly designed vertebral body trackers; 2) to demonstrate the feasibility of tracking vertebral motion in a cadaveric model; and 3) to quantify the vertebral motion that occurs during spinal surgery. SUMMARY OF BACKGROUND DATA Computer techniques are beginning to be applied to spine surgery. Validation of accuracy of methods of spinal tracking has not been reported. No information exists on the amount of vertebral motion that occurs during surgery. Because the new techniques require accurate positional information for the vertebral body, it is important to understand and evaluate methods of tracking vertebrae. METHODS An optical tracking system (Northern Digital, Waterloo, Ontario, Canada) was used to track custom-designed trackers. The reliability and accuracy of the trackers were evaluated in vitro. The proposed tracking methodology for human testing was performed using a cadaveric model, and after successful completion, human testing was done in the operating room to evaluate the motion of two vertebral bodies during exposure for instrumentation of the lumbar spine. This technique was used to evaluate the custom designed trackers effectiveness for tracking vertebral bodies for pedicle screw insertion. RESULTS The trackers developed were accurate and capable of tracking the motion of the spine. Measured motion of L3 and L4 during breathing was 1.3 mm, peak to peak. Maximal intraoperative motion of the vertebral bodies was 12.3 mm during maneuvers simulating dissection of soft tissue and targeting of spinal pedicles. CONCLUSIONS Significant motion occurs in lumbar vertebral bodies during surgery. Breathing motion alone is up to 1.3 mm, and surgeon-induced motion up to 10 times greater. Vertebral body trackers for use with an optical position sensor were capable of measuring this motion.
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Affiliation(s)
- N Glossop
- Department of Surgery, Sunnybrook Health Science Centre, Toronto, Ontario, Canada
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1307
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Markowski D, Hyland KE, Ginsberg HS, Hu R. Spatial distribution of larval Ixodes scapularis (Acari:Ixodidae) on Peromyscus leucopus and Microtus pennsylvanicus at two island sites. J Parasitol 1997; 83:207-11. [PMID: 9105297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Larval blacklegged ticks, Ixodes scapularis, were collected from white-footed mice. Peromyscus leucopus, on Prudence Island (where Microtus pennsylvanicus were not captured) and from meadow voles. M. pennsylvanicus, on Patience Island (where P. leucopus was absent) in Narragansett Bay, Rhode Island from June to October 1992. Ixodes scapularis larvae were also collected by flagging in the vicinity of host captures. On both islands, the relative density of larvae changed from July to September in samples from hosts, but not in flagging samples. Consequently, different sampling techniques can give different assessments of tick populations. Larvae were highly aggregated on both of the host species throughout the sampling period. As the mean relative density of larvae increased in the environment (based on flagging samples), larvae on the hosts became more dense and more crowded. Increased densities of larvae in the environment were not correlated with increased patchiness in the distribution of larvae among host animals on either island. Changes in the spatial distribution of larval I. scapularis on each host species had similar trends as larval densities and distributions within the environment. These results suggest that M. pennsylvanicus can serve as an alternative host for immature I. scapularis in a P. leucopus-free environment and have similar distributional characteristics.
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Affiliation(s)
- D Markowski
- Department of Biological Sciences, University of Rhode Island, Kingston 02881-0816, USA
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1308
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Abstract
BACKGROUND Only limited data exist comparing differences in sensory function and responses to neural blockade in infant and adult rats. Therefore, the authors sought (1) to compare baseline thermal, proprioceptive, and postural responses in infant, adolescent, and adult rats; and (2) to compare the effects of sciatic nerve blockade on thermal, proprioceptive, and postural responses in infant, adolescent, and adult rats. METHODS Infant, adolescent, and adult rats were evaluated for proprioceptive, thermal, and mechanical nociceptive and motor function before and after sciatic blockade using a detailed neurologic examination. RESULTS Mechanical and thermal nociception were present in all rats, starting from age 1 day. The withdrawal reflex latency to pinch was rapid at all ages, whereas that reaction to thermal stimulus depended on both age and temperature. In contrast, the tactile placing response and hopping response were absent at birth and developed completely during the first 10 days of life. The extensor postural thrust was absent in the first 2 weeks of life and developed variably during the first 50 days of life. Sciatic blockade duration is shorter in infant rats than in adult rats receiving the same dose per kilogram. A brief halothane general anesthetic at the time of sciatic injection in infant or adult rats does not alter the duration of blockade. CONCLUSIONS Infant rats show increased sensitivity to noxious thermal stimuli and similar response to deep mechanical stimuli compared with adult rats. Their proprioceptive and motor responses develop during the first 2 weeks of life. When doses are scaled by body weight, block duration is shorter in infant than in adult rats.
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Affiliation(s)
- D Hu
- Department of Anesthesia, Children's Hospital, Boston, Massachusetts, USA
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1309
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Steck PA, Pershouse MA, Jasser SA, Yung WK, Lin H, Ligon AH, Langford LA, Baumgard ML, Hattier T, Davis T, Frye C, Hu R, Swedlund B, Teng DH, Tavtigian SV. Identification of a candidate tumour suppressor gene, MMAC1, at chromosome 10q23.3 that is mutated in multiple advanced cancers. Nat Genet 1997; 15:356-62. [PMID: 9090379 DOI: 10.1038/ng0497-356] [Citation(s) in RCA: 2004] [Impact Index Per Article: 74.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Deletions involving regions of chromosome 10 occur in the vast majority (> 90%) of human glioblastoma multiformes. A region at chromosome 10q23-24 was implicated to contain a tumour suppressor gene and the identification of homozygous deletions in four glioma cell lines further refined the location. We have identified a gene, designated MMAC1, that spans these deletions and encodes a widely expressed 5.5-kb mRNA. The predicted MMAC1 protein contains sequence motifs with significant homology to the catalytic domain of protein phosphatases and to the cytoskeletal proteins, tensin and auxilin. MMAC1 coding-region mutations were observed in a number of glioma, prostate, kidney and breast carcinoma cell lines or tumour specimens. Our results identify a strong candidate tumour suppressor gene at chromosome 10q23.3, whose loss of function appears to be associated with the oncogenesis of multiple human cancers.
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Affiliation(s)
- P A Steck
- Department of Neuro-Oncology, University of Texas, M.D. Anderson Cancer Center, Houston 77030, USA.
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1310
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Than S, Hu R, Oyaizu N, Romano J, Wang X, Sheikh S, Pahwa S. Cytokine pattern in relation to disease progression in human immunodeficiency virus-infected children. J Infect Dis 1997; 175:47-56. [PMID: 8985195 DOI: 10.1093/infdis/175.1.47] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Cytokine mRNA expression and stimulus-induced cytokines were examined in peripheral blood mononuclear cells in 62 human immunodeficiency virus (HIV)-infected children and uninfected controls. Compared with that in controls, constitutive mRNA expression in patients was increased for tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, and interleukin (IL)-10 and decreased for IL-12; it was undetectable for IL-2 and IL-4 in both patients and controls. Stimulus-induced secretion of TNF-alpha, IFN-gamma, IL-12, and IL-4 was less than that in controls; IL-10 secretion was similar. There was no increase in stimulus-induced or constitutive IL-4 or IL-10 in children with severe immunologic deficit compared with controls. A higher stimulus-induced IL-10 secretion and a lower constitutive TNF-alpha mRNA were associated with a slower rate of disease progression, and TNF-alpha mRNA expression correlated with lower plasma HIV RNA. Thus, constitutive cytokine mRNA expression differs from stimulus-induced cytokine responses. The dominant defect in HIV-infected children appears to be one of reduced type 1 cytokines, predominantly IL-2.
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Affiliation(s)
- S Than
- Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, New York 11030, USA
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1311
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1312
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1313
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Hu R, Wei M, Ding X. [Changes in brain monoamine neurotransmitter in iron deficiency nonanemic rats]. Zhonghua Yu Fang Yi Xue Za Zhi 1996; 30:351-3. [PMID: 9388911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
An iron deficiency nonanemic rat model was established by feeding with low-iron diet (11.9 mg/kg) to study if there exists biochemical abnormality in brain tissues. Iron contents of the brain, activities of monoamine oxidase (MAO) in the corpus striatum, and the contents of monoamine neurotransmitter and its metabolite in the cerebral cortex and hippocampus were determined by DCP-AES technique, enzyme histochemical method, and high performance liquid chromatography with electrochemical detection (HPLC-ECD), respectively. Results showed that iron contents and activities of MAO in brain tissues of iron deficiency nonanemic rats reduced significantly, and contents of norepinephrine (NE) and 5-hydroxytryptamine (5-HT) in cerebral cortex were significantly higher than those of controls, while 5-hydroxydroxytryptamine acid (5-HIAA) metabolite of 5-HT in the hippocampus was lower than that of controls. It indicated that there existed metabolic abnormality of monoamine neurotransmitter in the brain tissues of iron deficiency nonanemic rats. Also, this study laid a biochemical basis for abnormal mental and behavioral development caused by iron deficiency.
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Affiliation(s)
- R Hu
- Department of Pediatrics Affiliated Hospital, Shandong Medical University, Jinan
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1314
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Hu R, Yeh MT, Hyland KE, Mather TN. Experimental Babesia microti infection in golden hamsters: immunoglobulin G response and recovery from severe hemolytic anemia. J Parasitol 1996; 82:728-32. [PMID: 8885880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
We described the parasitemia, hematologic changes, and immunity developed by golden hamsters during 8 wk of infection with Babesia microti following experimental inoculation. All 8 hamsters used in this study were readily infected. Animals attained peak parasitemias asynchronously but within a 2-wk period. Most of the animals reached their peak parasitemia by 4 wk postinoculation, attaining a mean +/- SD of 21.9 +/- 9.4% infected erythrocytes (range = 20-35%). Red blood cell count, packed cell volume, and hemoglobin level were used to monitor the course of the hemolytic anemia experienced by infected hamsters. All 3 measures corresponded inversely to the parasitemia; significant hematologic changes (P = 0.0001) were observed during the 8 wk of monitoring. Although all hamsters suffered from severe hemolytic anemia, they also recovered within the same period. Golden hamsters developed a detectable anti-B. microti IgG response by 2 wk postinoculation. Individual animals typically attained peak antibody levels (> or = 1:8, 192) 1 wk after the peak parasitemia. Hamsters retained a high IgG titer (> or = 1:4,096), although parasitemias fell dramatically, fluctuating thereafter at low levels (< 5%).
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Affiliation(s)
- R Hu
- Center for Vector-Bome Disease, University of Rhode Island, Kingston 02881, USA
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1315
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Hu R, Oyaizu N, Than S, Kalyanaraman VS, Wang XP, Pahwa S. HIV-1 gp160 induces transforming growth factor-beta production in human PBMC. Clin Immunol Immunopathol 1996; 80:283-9. [PMID: 8811049 DOI: 10.1006/clin.1996.0125] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Transforming growth factor-beta (TGF-beta) is a multifunctional cytokine secreted by many mononuclear cells in peripheral blood (PBMC) and has diverse effects on cellular and humoral immunity. Increased TGF-beta mRNA expression has been reported in PBMC of HIV-infected patients, but the mechanism by which HIV induces TGF-beta secretion is unknown. In this study, we observed that HIV gp160 could induce significant TGF-beta secretion and TGF-beta mRNA expression in PBMC from HIV-seronegative healthy donors. The cellular source of TGF-beta was attributed to non-T cells, presumably monocytes. Specificity of secreted TGF-beta was confirmed by the addition of anti-TGF-beta mAb which abrogated the proliferative response of CCL-64 cells by gp160-treated culture supernatants. Soluble CD4 blocked the gp160-induced TGF-beta production, suggesting that CD4-gp160 interaction is required to induce TGF-beta production. Our results suggest that HIV-1 gp160 may contribute to the immune defects in HIV infection by inducing TGF-beta secretion.
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Affiliation(s)
- R Hu
- Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, New York 11030, USA
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1316
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Mather TN, Nicholson MC, Hu R, Miller NJ. Entomological correlates of Babesia microti prevalence in an area where Ixodes scapularis (Acari:Ixodidae) is endemic. J Med Entomol 1996; 33:866-870. [PMID: 8840700 DOI: 10.1093/jmedent/33.5.866] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Zoonotic prevalence of Babesia microti Franca piroplasms infecting white-footed mice, Peromyscus leucopus Rafinesque, was determined at 34 sites in Rhode Island where nymphal blacklegged tick, Ixodes scapularis Say, densities ranged from low to hyperabundant (1.7-525.3 nymphs per hour of flagging). Babesia was only detected at sites where tick abundance was moderate to high (> 20 nymphs per hour of flagging) and appeared to exhibit a clumped distribution. Where B. microti was detected, the mean number of nymphal ticks collected per hour of flagging was 229.2 compared with a mean of 40.1 at sites where Babesia was not detected. By combining the spatial occurrence of Babesia with a tick density database in a geographic information system, it may be possible to predict the pattern of zoonotic and human infection with B. microti.
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Affiliation(s)
- T N Mather
- Center for Vector-Borne Disease, University of Rhode Island, Kingston 02881-0804, USA
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1317
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1318
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Boyer MI, Ribeiro E, Hu R, Powell JN. Small versus large diameter closed-section femoral nails for the treatment of femoral shaft fractures: is there a difference? J Trauma 1996; 41:279-82. [PMID: 8760537 DOI: 10.1097/00005373-199608000-00014] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
UNLABELLED A retrospective series of 99 femoral shaft fractures treated by small diameter (10 and 11 mm) and large diameter (> 11 mm) closed section femoral nails from November 1989 to September 1993 was analyzed. No significant differences in the parameters of bony union and time to full weight bearing were seen between the two groups nor were there significant differences between the rate of secondary procedures. There were no broken nails in either group and there was no difference in the overall respiratory complication rate. CONCLUSION No statistically significant differences existed between the small and large diameter groups except for the mean age and mean follow-up period. Small diameter nails can be used safely without the risk of nail breakage.
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Affiliation(s)
- M I Boyer
- Division of Orthopaedic Surgery, Sunnybrook Health Science Centre, Toronto, Canada
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1319
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Varga E, Hu R, Hearn TC, Woodside T, Yang JP. Biomechanical analysis of hemipelvic deformation after corticospongious bone graft harvest from the posterior iliac crest. Spine (Phila Pa 1976) 1996; 21:1494-9. [PMID: 8817775 DOI: 10.1097/00007632-199607010-00002] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
STUDY DESIGN The stiffness of the hemipelvis during simulated physiologic loading and the bone deformation in the remaining posterior ilium after the harvest of increasing sizes of corticospongious bone graft were compared with values in intact bone. OBJECTIVES To quantify the biomechanical effects of the removal of bone grafts from the posterior ilium and to relate the size of graft removed to the stiffness of the hemipelvis and deformation of the remaining bone. SUMMARY OF BACKGROUND DATA Bone fractures and pelvic instability have been reported to complicate graft harvest from the posterior iliac crest. There is no quantitative data relating graft size to the mechanical properties of the remaining ilium. METHODS Seven cadaveric hemipelves were loaded with a materials testing machine through the superior sacrum while supported at the acetabulum and stabilized with a cable fixed to the ilium. Force and displacement histories and deformation in the greater sciatic notch were recorded for the intact bone and after removal of corticospongious bone graft in 1.5-cm increments from the posterior iliac crest. RESULTS If the length of the removed corticospongious bone graft exceeded 3.0 cm, the stiffness of the posterior pelvic ring decreased, and deformation in the remaining bone increased substantially. CONCLUSIONS Removal or bone graft in excess of 3 cm from the posterior ilium increases the risk of iatrogenic fatigue fracture.
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Affiliation(s)
- E Varga
- Orthopaedic Biomechanics Research Laboratory, Sunnybrook Health Science Centre, University of Toronto, Ontario, Canada
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1320
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Du C, Hu R, Csernansky CA, Liu XZ, Hsu CY, Choi DW. Additive neuroprotective effects of dextrorphan and cycloheximide in rats subjected to transient focal cerebral ischemia. Brain Res 1996; 718:233-6. [PMID: 8773794 DOI: 10.1016/0006-8993(96)00162-x] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Previous studies have implicated both excitotoxicity and apoptosis in the pathogenesis of cerebral infarction induced by focal ischemic insults. Here we tested the possibility that the NMDA antagonist, dextrorphan, and the protein synthesis inhibitor, cycloheximide, would produce additive protective effects in a rodent model of focal ischemia-reperfusion. Transient focal cerebral ischemia was induced by a 90 min period of ligation of the right middle cerebral artery and both common carotid arteries. Administration of either 30 mg/kg dextrorphan or 0.5 mg/kg cycloheximide, given i.p. 15 min before ischemia, reduced infarct volume by about 65%. When optimal concentrations of each drug were given together, infarct volume was reduced by 87% as measured 14 days later. These observations support the idea that both excitotoxicity, and apoptosis dependent on new protein synthesis, contribute to cerebral infarction after transient focal ischemia in the rat.
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Affiliation(s)
- C Du
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
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1321
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Abstract
Focal cerebral ischemia confined to the cerebral cortex in the right middle cerebral artery (MCA) territory was induced by temporary ligation of the MCA and both common carotid arteries (CCAs). Reperfusion was initiated by releasing all three arterial occlusions after 90 min of ischemia. Infarct volume was morphometrically measured after triphenyltetrazolium chloride staining 24 h postischemia. Blood-brain barrier breakdown was assessed 4 h postischemia by measuring vascular permeability to fluorescein isothiocyanate-conjugated dextran (FITC-D), a macromolecule tracer. Ischemic brain edema was measured based on percent water content, 24 h postischemia. Dextrorphan (DX) 20-10 mg/kg given ip 15 min before ischemia reduced infarct volume in a dose-dependent manner with an apparent U-shaped dose-response curve; best protection was observed at 30 mg/kg. Posttreatment at 30 min, but not 60 min, was still effective. DX (30 mg/kg, given 15 min before ischemia) also reduced the postischemic increase in vascular permeability and brain edema in the right MCA cortex. Results from this study support the idea that NMDA receptor activation contributes to blood-brain barrier breakdown and brain edema after ischemic insults
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Affiliation(s)
- C Du
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
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1322
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Abstract
The temporal evolution of cerebral infarction was examined in rats subjected to transient occlusion of both common carotid arteries and the right middle cerebral artery. After severe (90-min) ischemia, substantial right-sided cortical infarction was evident within 6 h and fully developed after 1 day. After mild (30-min) ischemia, no cortical infarction was present after 1 day. However, infarction developed after 3 days; by 2 weeks, infarction volume was as large as that induced by 90-min ischemia. These data suggest that infarction after mild focal ischemia can develop in a surprisingly delayed fashion. Some evidence of neuronal apoptosis was present after severe ischemia, but only to a limited degree. However, 3 days after mild ischemia, neurons bordering the maturing infarction exhibited prominent TUNEL staining, and DNA prepared from the periinfarct area of ischemic cortex showed internucleosomal fragmentation. Furthermore, pretreatment with 1 mg/kg cycloheximide markedly reduced infarction volume 2 weeks after mild ischemia. These data raise the possibility that apoptosis, dependent on active protein synthesis, contributes to the delayed infarction observed in rats subjected to mild transient focal cerebral ischemia.
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Affiliation(s)
- C Du
- Department of Neurology, Washington University School of Medicine, St Louis, Missouri 63110, USA
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1323
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Abstract
STUDY DESIGN Cross-section observational study of incident spinal fractures using an administrative data-base. OBJECTIVES To identify and define all patients who have spinal fractures within a complete population. SUMMARY OF BACKGROUND DATA The true incidence of spinal column and cord injury is not known. Previous studies have been institutional or practice based. Accurate information concerning the magnitude of the spinal injury population and their characteristics may provide more rational basis for public health decision making and resource allocation. METHODS The study dates were April 1, 1981 to March 31, 1984. Using the Manitoba Health Services Insurance Plan database, all patients with ICD-9-CM coding of 805.x and 806.x (spinal column fracture with and without spinal cord injury) were identified. Incidence rates, age and gender distribution, and ambulatory and hospital contracts were identified. Hospital discharge abstracts were used to classify mechanisms of injury, associated injuries, and length of stay. RESULT The annual incidence rate of spinal fracture was 64 per 100,000. Two thousand sixty-three patients were identified, with 944 being admitted to the hospital. There were two peaks of incidence occurring in young men and elderly women. Of the hospitalized patients, 182 had cervical injury, 286 had thoracic fracture, and 403 had injury in the lumbosacral spine Associated injuries occurred in 38% of hospitalized patients. Length of stay was an average of 38.5 days. Overall mortality was 41%. Neurologic injury occurred in 122 patients. CONCLUSIONS Ambulatory care of spine injuries is more common than hospital care. Two peaks of incidence occur-in young men and elderly women. Future decisions for research, public health policy, and resource allocation can be based on these data.
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Affiliation(s)
- R Hu
- Department of Surgery, Faculty of Medicine, University of Toronto, Canada
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1324
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Hu R, M�ller PC. Independent joint control: Estimation and compensation of coupling and friction effects in robot position control. J INTELL ROBOT SYST 1996. [DOI: 10.1007/bf00435726] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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1325
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Hu R, Wang WZ, Du YP. [Quality control of baccalaureate students practice of nursing process through systems management]. Zhonghua Hu Li Za Zhi 1996; 31:24-6. [PMID: 8716716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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1326
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yeh MT, Bak JM, Hu R, Nicholson MC, Kelly C, Mather TN. Determining the duration of Ixodes scapularis (Acari: Ixodidae) attachment to tick-bite victims. J Med Entomol 1995; 32:853-858. [PMID: 8551509 DOI: 10.1093/jmedent/32.6.853] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The duration of tick attachment is one factor associated with risk for human infection caused by several tick-borne pathogens. We measured tick engorgement indices at known time intervals after tick attachment and used these indices to determine the length of time that ticks were attached to tick-bite victims in selected Rhode Island and Pennsylvania communities where the agents of Lyme disease and human babesiosis occur. The total body length and width as well as the length and width of the scutum were measured on nymphal and adult female Ixodes scapularis Say removed from laboratory animals at 0, 12, 24, 36, 48, 60, and 72 h after their attachment. Three engorgement indices were calculated at each time interval. In addition, engorgement indices measurements were recorded for 504 ticks submitted to a commercial laboratory for pathogen detection testing between 1990 and 1992. No detectable change was observed in the average engorgement indices for either nymphal or adult ticks between 0 and 24 h of attachment using any of the engorgement indices. After 24 h of tick attachment, all engorgement indices continuously increased: average indices for nymphs attached 36, 48, and 60 h were significantly different from those attached < or = 24 h and from each other. Similarly, average engorgement indices for adult ticks attached < or = 36 h were significantly different from those attached for 48 h or more. More than 60% of tick-bite victims removed adult ticks by 36 h of attachment, but only 10% found and removed the smaller nymphal ticks within the first 24 h of tick feeding. The duration of tick attachment may serve as a useful predictor of risk for acquiring various infections, such as Lyme disease and babesiosis, transmitted by I. scapularis. Regression equations developed herein correlate tick engorgement indices with duration of feeding. A table containing specific engorgement index prediction intervals calculated for both nymphs and adults will allow the practitioner or clinical laboratory to use easily measured tick engorgement indices to predict transmission risk by determining the duration of feeding by individual ticks.
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Affiliation(s)
- M T yeh
- Center for Vector-Borne Disease, University of Rhode Island, Kingston 02881-0804, USA
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1327
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Hu R, Dimonie VL, El-Aasser MS, Pearson RA, Sperling LH, Hiltner A, Mylonakis SG. Interfacial aspects of latex ipns for toughening polycarbonate. I. Synthesis and characterization. J Appl Polym Sci 1995. [DOI: 10.1002/app.1995.070580217] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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1328
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Li Y, Hui Y, Zhou J, Liu X, Chen S, Hu R, Ying Z. mRNA expression of vimentin gene in lens of transgenic mouse and DNA amplification in human cataracts. Yan Ke Xue Bao 1995; 11:113-6. [PMID: 8758834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
PURPOSE To investigate the role of vimentin gene in cataractogenesis. METHODS The 12.7kb chicken vimentin genes were microinjected into the male pronuclei of 918 fertilized mice eggs. 841 injected embryos were transferred into oviducts of pseudopregnant recipient females, of which 12 pregnant mice gave birth to 49 offspring mice. The integration and expression of exogenous gene in the offspring were analysed by Southern and Northern blot hybridizations. In the human senile cataract, the lens vimentin gene was analyzed with the chicken vimentin gene probe. RESULTS It showed that four of F1 offspring were transgenic mice in which the chicken vimentin gene was integrated in their genomes. The transgenic band was 12kb, similar to the 12.7kb chicken vimentin fragment injected. One 2kb vimentin mRNA was visualized on E2 mouse lens blot, which revealed that the chicken vimentin gene was efficiently expressed in this transgenic mouse. In the human senile cataract lens, 12kb BamHI-restricted vimentin fragments displayed a stronger hybridization signal than that of the control lens in Southern blot analysis. It implies that the formation of human senile cataract may be associated with the amplification of vimentin gene. CONCLUSIONS We have successfully developed four transgenic mice bearing chicken vimentin gene and having mRNA expression which can be used for further study. It is to be observed if the normal lens cell function is affected by the expressed product and cataract occurs in our transgenic mice. The cause of the gene amplification in human cataract remains for further investigation.
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Affiliation(s)
- Y Li
- Department of Ophthalmology, Xijing Hospital, 4th Medical University, Xian
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1329
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Chirmule N, McCloskey TW, Hu R, Kalyanaraman VS, Pahwa S. HIV gp120 inhibits T cell activation by interfering with expression of costimulatory molecules CD40 ligand and CD80 (B71). The Journal of Immunology 1995. [DOI: 10.4049/jimmunol.155.2.917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
One mechanism of the immune suppression in HIV infection has been postulated as being caused by the interaction of HIV envelope glycoprotein gp120 with CD4 molecules. Thus, pretreatment of purified peripheral blood T cells or CD4+ T cell clones with gp120 (or an anti-CD4 mAb) results in inhibition of anti-CD3 mAb-induced proliferative responses. In this study, we have analyzed the role of the interacting pairs of costimulatory molecules, CD28-B71 (CD80) and CD40 ligand (CD40L)-CD40, to elucidate further the mechanism of HIV gp120-induced inhibitory effects on T cell functions. Interactions between CD28-B71 and CD40L-CD40 were found to be essential for the anti-CD3 mAb-induced T cell proliferation, as demonstrated by up-regulation of B71 and CD40L and the ability of anti-B71 and anti-CD40L mAbs to inhibit this response. Pretreatment of CD4+ T cells with gp120 before CD3 ligation with anti-CD3 mAb resulted in failure of up-regulation of CD40L on T cells and B71 on APC. Exogenous addition of anti-CD28 mAb overcame the inhibitory effect of gp120 on anti-CD3 mAb-induced T cell proliferation. We conclude that binding of gp120 to CD4 molecules on T cells may interrupt the sequential cascade of intercellular interaction involving 1) Ag/MHC class II-TCR/CD4, 2) CD40L-CD40, and 3) B71-CD28. These studies indicate that the CD4-gp120 interaction results in dysregulation of expression of costimulatory molecules, CD40L, and B71 expression on T cells and APC, respectively, thereby contributing to the T cell hyporesponsiveness in HIV infection.
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Affiliation(s)
- N Chirmule
- Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, NY 11030, USA
| | - T W McCloskey
- Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, NY 11030, USA
| | - R Hu
- Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, NY 11030, USA
| | - V S Kalyanaraman
- Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, NY 11030, USA
| | - S Pahwa
- Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, NY 11030, USA
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1330
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Chirmule N, McCloskey TW, Hu R, Kalyanaraman VS, Pahwa S. HIV gp120 inhibits T cell activation by interfering with expression of costimulatory molecules CD40 ligand and CD80 (B71). J Immunol 1995; 155:917-24. [PMID: 7541827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
One mechanism of the immune suppression in HIV infection has been postulated as being caused by the interaction of HIV envelope glycoprotein gp120 with CD4 molecules. Thus, pretreatment of purified peripheral blood T cells or CD4+ T cell clones with gp120 (or an anti-CD4 mAb) results in inhibition of anti-CD3 mAb-induced proliferative responses. In this study, we have analyzed the role of the interacting pairs of costimulatory molecules, CD28-B71 (CD80) and CD40 ligand (CD40L)-CD40, to elucidate further the mechanism of HIV gp120-induced inhibitory effects on T cell functions. Interactions between CD28-B71 and CD40L-CD40 were found to be essential for the anti-CD3 mAb-induced T cell proliferation, as demonstrated by up-regulation of B71 and CD40L and the ability of anti-B71 and anti-CD40L mAbs to inhibit this response. Pretreatment of CD4+ T cells with gp120 before CD3 ligation with anti-CD3 mAb resulted in failure of up-regulation of CD40L on T cells and B71 on APC. Exogenous addition of anti-CD28 mAb overcame the inhibitory effect of gp120 on anti-CD3 mAb-induced T cell proliferation. We conclude that binding of gp120 to CD4 molecules on T cells may interrupt the sequential cascade of intercellular interaction involving 1) Ag/MHC class II-TCR/CD4, 2) CD40L-CD40, and 3) B71-CD28. These studies indicate that the CD4-gp120 interaction results in dysregulation of expression of costimulatory molecules, CD40L, and B71 expression on T cells and APC, respectively, thereby contributing to the T cell hyporesponsiveness in HIV infection.
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Affiliation(s)
- N Chirmule
- Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, NY 11030, USA
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1331
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Klempner MS, Noring R, Epstein MP, McCloud B, Hu R, Limentani SA, Rogers RA. Binding of human plasminogen and urokinase-type plasminogen activator to the Lyme disease spirochete, Borrelia burgdorferi. J Infect Dis 1995; 171:1258-65. [PMID: 7751701 DOI: 10.1093/infdis/171.5.1258] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Many bacteria that spread in the skin produce enzymes that digest extracellular matrix components. Borrelia burgdorferi spreads from a skin inoculation site to form the characteristic erythema migrans skin lesion. It was determined that B. burgdorferi does not produce collagenase, elastase, hyaluronidase, or other enzymes that digest extracellular matrix components. However, B. burgdorferi bound human plasmin, plasminogen (Pgn), and urokinase-type plasminogen activator (uPA). When spirochetes were sequentially incubated with Pgn and uPA, bioactive plasmin was generated on the surface of B. burgdorferi. B. burgdorferi did not produce an endogenous Pgn activator. Fluorochrome-conjugated uPA and Pgn colocalized to the terminus of the spirochete. In a mouse model, uPA-treated B. burgdorferi were more infectious than control spirochetes. Binding of host uPA and Pgn to form a bioactive extracellular matrix protease on B. burgdorferi represents a mechanism that could facilitate dissemination and localization of spirochetes to sites of vascular injury.
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Affiliation(s)
- M S Klempner
- Department of Medicine, New England Medical Center, Tufts University School of Medicine, Boston, Massachusetts, USA
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1332
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Chu J, Hu R, Miwa T, Takeuchi T. Indirect photometric detection of inorganic anions by microcolumn liquid chromatography using anthraquinone-disulfonate as visualization agent. Chromatographia 1995. [DOI: 10.1007/bf02269898] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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1333
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1334
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Hu R, Hearn T, Yang J. Bone graft harvest site as a determinant of iliac crest strength. Clin Orthop Relat Res 1995:252-6. [PMID: 7641447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Bone graft harvest site fracture can occur after removal of bone from the anterior iliac crest. No biomechanically proven guidelines for safe removal of bone exist. Cadaveric hemipelves were tested in a materials testing system machine, with the harvest site occurring 15-mm posterior to the anterosuperior iliac spine in 8 specimens and 30-mm posterior in 7 specimens. These pelves were then tested to failure by simulating avulsion fractures caused by the forces of the flexors of the hip. Average force at failure was 783 N (standard deviation, +/- 333 N) in the 15-mm group and 1917 N (standard deviation, +/- 735) in the 30-mm group. This study provides objective data which demonstrate that harvest 30 mm posterior to the anterosuperior iliac spine weakens the iliac crest less than harvest 15 mm posterior to the anterosuperior iliac crest. To minimize the possibility of iliac crest fracture after bone graft harvest, bone should be removed at least 30 mm from the anterior superior iliac spine.
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Affiliation(s)
- R Hu
- Division of Orthopaedic Surgery, Sunnybrook Health Sciences Centre, Toronto, Canada
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1335
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Oyaizu N, McCloskey TW, Than S, Hu R, Pahwa S. Mechanism of apoptosis in peripheral blood mononuclear cells of HIV-infected patients. Adv Exp Med Biol 1995; 374:101-14. [PMID: 7572384 DOI: 10.1007/978-1-4615-1995-9_9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Lymphocytes from patients with HIV-infection have been shown to undergo accelerated spontaneous apoptosis. Binding of CD4 molecules by HIV envelope protein gp120 and anti-gp120 antibodies can lead to crosslinking of CD4 molecules (CD4XL) in vitro and conceivably in vivo. We have recently shown that CD4XL in vitro, when performed in unfractioned peripheral blood mononuclear cells (PBMC) on normal HIV seronegative donors, is by itself sufficient to induce T cell apoptosis (Blood 82:3392, 1993). To further examine the mechanisms involved in apoptosis, we have examined the expression of Fas antigen (Fas) using 3 color flow cytometry. Fas is a cell surface molecule known to mediate apoptosis-triggering signals. We induced CD4XL in PBMC obtained from normal donors, either by anti-CD4 mAb Leu3a or by HIV-1 envelope protein gp160. PBMC subpopulations were examined for Fas Ag expression and for apoptosis induction by flow cytometry. CD4XL was found to result in increased Fas expression as well as Fas mRNA in lymphocytes and the up-regulated Fas Ag was closely correlated with apoptotic cell death. CD4XL in PBMC also resulted in induction of the cytokines INF-tau and TNF-alpha in the absence of IL-2 and IL-4 secretion. Both these cytokins contributed to Fas Ag up-regulation and antibodies to TNF-alpha and INF-tau abrogated CD4XL-induced Fas up-regulation and T-cell apoptosis. These findings suggest that CD4XL occurring in vivo might play an important role in inducing an abberant cytokine profile (which has been observed in HIV infected individuals) and also in triggering of T-cell apoptosis.
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Affiliation(s)
- N Oyaizu
- Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, New York, New York 11030, USA
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1336
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Takeuchi T, Hu R, Miwa T. Retention behavior of aromatic hydrocarbons in reversed-phase liquid chromatography with ion-exchange-induced stationary phases. Chromatographia 1994. [DOI: 10.1007/bf02268286] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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1337
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Hu R, Oyaizu N, Kalyanaraman VS, Pahwa S. HIV-1 gp160 as a modifier of Th1 and Th2 cytokine response: gp160 suppresses interferon-gamma and interleukin-2 production concomitantly with enhanced interleukin-4 production in vitro. Clin Immunol Immunopathol 1994; 73:245-51. [PMID: 7523014 DOI: 10.1006/clin.1994.1194] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Disease progression in HIV-1 infection is reported to be associated with a gradual shift in CD4+ T cell function from a Th type 1 to a Th type 2 of response, but the underlying mechanism remains unclear. In this study, the effect of HIV-1 envelope glycoprotein gp160 on secretion of cytokines IFN-gamma/IL-2 (Th1 type) and IL-4 (Th2 type) was analyzed using freshly isolated unfractioned peripheral blood mononuclear cells (PBMC), CD4+ T cell lines, and PBMC depleted of CD8+ cells (CD8- PBMC) as target cells. Pretreatment of these cells with HIV gp160 significantly reduced PHA-induced secretion of IFN-gamma and IL-2 but augmented IL-4 production. This effect of gp160 was not observed when the target cells consisted of PBMC depleted of either CD4+ cells (CD4- PBMC) or of CD2+ cells (CD2- PBMC). Pretreatment of gp160 with soluble CD4-immunoglobulin chimeric molecules abrogated the observed effects of gp160, suggesting that CD4-gp120 interaction is required for modification of the cytokine secretion profile. Our results suggest that exposure of CD4+ T cells to HIV-1 envelope proteins may modify the responses evoked by additional stimuli in favor of a Th2-type dominant response.
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Affiliation(s)
- R Hu
- Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, New York, New York 11030
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1338
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Oyaizu N, McCloskey TW, Than S, Hu R, Kalyanaraman VS, Pahwa S. Cross-linking of CD4 molecules upregulates Fas antigen expression in lymphocytes by inducing interferon-gamma and tumor necrosis factor-alpha secretion. Blood 1994; 84:2622-31. [PMID: 7522637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
We have recently shown that, in unfractioned peripheral blood mononuclear cells (PBMCs), the cross-linking of CD4 molecules (CD4XL) is sufficient to induce T-cell apoptosis. However, the underlying mechanism for the CD4XL-mediated T-cell apoptosis is largely unknown. Several recent studies have shown that Fas antigen (Ag), a cell-surface molecule, mediates apoptosis-triggering signals. We show here that cross-linking of CD4 molecules, induced either by anti-CD4 monoclonal antibody (MoAb) Leu3a or by human immunodeficiency virus-1 (HIV-1) envelope protein gp160, upregulates Fas Ag expression as well as Fas mRNA in normal lymphocytes. Addition of the tyrosine protein kinase inhibitor genistein or of the immunosuppressive agent cyclosporin A abrogated these effects. The upregulation of Fas Ag closely correlated with apoptotic cell death, as determined by flow cytometry. In addition, CD4XL resulted in the induction of interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) in the absence of interleukin-2 (IL-2) and IL-4 secretion in PBMCs. Both INF-gamma and TNF-alpha were found to contribute to Fas Ag upregulation and both anti-IFN-gamma and anti-TNF-alpha antibodies blocked CD4XL-induced Fas Ag upregulation and lymphocyte apoptosis. These findings strongly suggest that aberrant cytokine secretion induced by CD4XL and consequent upregulation of Fas Ag expression might play a critical role in triggering peripheral T-cell apoptosis and thereby contribute to HIV disease pathogenesis.
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Affiliation(s)
- N Oyaizu
- Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, NY
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1339
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Abstract
The findings of this study emphasize the importance of distraction in obtaining and maintaining reduction in upper thoracic fractures that are unstable and collapsing into kyphosis. It also shows that a Luque rectangle construct cannot fulfill this function adequately in this type of fracture. Thirty-four consecutive cases of surgically treated upper thoracic spine fractures were reviewed. Two patients died, and 4 were lost to follow-up, so after a minimum 6-month clinical and radiographic follow-up there were 11 patients in the Luque group and 17 in the distraction rod group. Preoperatively, there was no significant difference in age, sex, level of injury or severity of kyphosis between the two groups. The Luque stabilization took an average of 1 h longer. There was no difference in local, general or neurological complications between the groups. Pain at the final follow-up was the same according to analgesic use. The kyphosis in the Luque group increased progressively from preoperative to postoperative values continued and to increase. In the distraction rod group the postoperative kyphosis was improved compared with the preoperative values. At final follow-up the kyphosis had returned nearly to the preoperative values. The difference in the adequacy of the reduction as measured by percentage of anterior collapse between the two groups is highly statistically significant: distraction rod better postoperatively, P = 0.0114 (Student's t-test); distraction rod better at final follow-up, P = 0.0054 (Student's t-test).
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Affiliation(s)
- C B Huckell
- Sunnybrook Health Science Centre, University of Toronto, Canada
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1340
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Chirmule N, Wang XP, Hu R, Oyaizu N, Roifman C, Pahwa R, Kalyanaraman VS, Pahwa S. Envelope glycoproteins of HIV-1 interfere with T-cell-dependent B cell differentiation: role of CD4-MHC class II interaction in the effector phase of T cell help. Cell Immunol 1994; 155:169-82. [PMID: 8168144 DOI: 10.1006/cimm.1994.1110] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
T-cell-dependent B cell differentiation involves two phases: an inductive phase of T cell activation followed by an effector phase, which involves stimulation of B cells by activated T cells. We have previously demonstrated that anti-CD3 mAb and antigen-induced T-cell-dependent B cell functions are inhibited by HIV-1 envelope glycoprotein, gp120, at the inductive phase of T-cell-dependent B cell response. In this study we have investigated whether gp120 also inhibits the effector phase of interactions involved in T-cell-dependent-B cell differentiation response. For these studies, CD4+ T cells were first activated with antigen or pokeweed mitogen, cultured with soluble HIV-gp120 or medium for 2 hr, and washed. Coculture of gp120-treated preactivated T cells with autologous B cells resulted in impairment of IgG secretion, but did not affect IgM secretion significantly. The IgG secretion was restored by the addition of PMA (activator of protein kinase C) or forskolin (activator of adenylate cyclase), but not by the addition of ionomycin (inducer of intracellular calcium) to the T plus B cell cultures. A similar pattern of Ig secretion (IgM, no IgG) was observed with B cells of a patient with bare lymphocyte syndrome, indicating a requirement for MHC class II molecule interaction with T cells. These studies suggest that the effector phase of T-B cell interactions are impaired by gp120, and that the mechanism involves a signal transducing event(s), which is dependent upon cyclic AMP and/or protein kinase C. Furthermore, these latter reactions occur subsequent to T-B cell contact-dependent interactions at the effector phase, which involve MHC class II molecules on B cells and CD4 molecules on T cells.
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Affiliation(s)
- N Chirmule
- Department of Pediatrics, North Shore University Hospital, Cornell University Medical College, Manhasset, New York 11030
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1341
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Abstract
This case report is the first to report severe spinal degeneration and destruction in Wilson's disease. The presentation, assessment, and decision making for treatment are discussed. This condition should be considered in patients with Wilson's disease who present with back pain.
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Affiliation(s)
- R Hu
- Division of Orthopaedic Surgery, University of Toronto, Ontario
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1342
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Abstract
In order to evaluate the efficacy of L-phenylalanine (L-Phe) in combination with UVA therapy for vitiligo an open trial (149 patients, 18 months) and a small double-blind trial (32 patients, 6 months) were conducted. Oral L-Phe loading resulted in peak plasma levels of L-Phe after 30-60 min and a slight increase in the plasma tyrosine level. Response to L-Phe plus UVA irradiation was positive, and various grades of repigmentation not exceeding 77% in the open and 60% in the blind trial were observed. An increased L-Phe dose resulted in increased L-Phe plasma levels but not in improved clinical results. The optimal L-Phe dose appears to be lower than 50 mg/kg/day. Although it is difficult to draw firm conclusions from the present investigation, we think that L-Phe may have a place in the treatment of vitiligo and its role merits further investigation.
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Affiliation(s)
- A H Siddiqui
- Department of Dermatology, Academisch Medisch Centrum, University of Amsterdam, The Netherlands
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1343
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Hu R. Treatment of acute lumbar sprain with acupuncture at Fuyang (UB 59). J TRADIT CHIN MED 1993; 13:264-5. [PMID: 8139275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- R Hu
- Department of Acupuncture, Fengcheng City People's Hospital, Jiangxi Province
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1344
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Hu R. [Application of the APIE (assessment, plan, implementation, evaluation) process in clinical teaching of baccalaureate nursing students]. Zhonghua Hu Li Za Zhi 1993; 28:665-667. [PMID: 8124780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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1345
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Abstract
Knowledge of pedicle diameter and surface landmarks is crucial for safe placement of screws. Little attention has been paid to variations of entrance points for pedicle screws, differentiation of male and female pedicle sizes and pedicle size differences in nonwhite populations. Forty thoracolumbar spinal columns from T9 to L5 were measured using vernier calipers. Cephalad-caudad and medial-lateral diameter of the pedicle, length of the pedicle from posterior cortex to anterior cortex at the midline and parallel to midline was measured. Relation of the centre of the pedicle to the transverse process (TP) and to the superior facet joint was noted. Twenty-five male and 15 female specimens were measured. Average pedicle width in the female was 5.2 mm at T9 (SD 0.9) to 13 mm at L5 (SD 2.7) and in the male 6.0 mm at T9 (SD 1.1) to 12.8 mm at L5 (SD 2.7). Cephalad caudad diameter was 12.5 mm (SD 1.2) at T9 to 20.5 mm (SD 3.6) at L5 in the male and in the female 12.2 mm (SD 1.3) at T9 to 18.7 mm (SD 3.9) at L5. All specimens had starting points cephalad to the midpoint of the TP at T9. At L5, 37 of 40 specimens had starting points at the midpoint of the TP. Starting points were parallel to the middle or lateral third of the superior facet joint at T9. At L5 starting points were at least one third of the facet joint lateral to the lateral border of the facet. Female pedicle width was smaller than male at T9 (P = 0.03) and T12 (P = 0.04).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- S Hou
- Department of Orthopaedics, Trauma Hospital of 304th PLA, Post-Graduate Medical College, Beijing, China
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1346
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Hu R, Gan Y, Liu J, Miller D, Zoon KC. Evidence for multiple binding sites for several components of human lymphoblastoid interferon-alpha. J Biol Chem 1993; 268:12591-5. [PMID: 8509399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The antiproliferative and competitive binding activities of 20 purified components of human lymphoblastoid interferon (IFN)-alpha were compared with that of recombinant human IFN-alpha 2b on Daudi and AU937 cells. We observed broad ranges of antiproliferative activities of the IFN-alpha components on these cell lines. Daudi cells were more sensitive to the IFN-alpha components than AU937 cells; the concentrations of the components that resulted in 50% inhibition of cell growth ranged from 0.003 ng/ml to > 10 ng/ml on Daudi cells and 0.05 ng/ml to > 200 ng/ml on AU937 cells. Component o was the most active human IFN-alpha on both cell lines. Scatchard analysis demonstrated that the number of IFN-alpha 2b binding sites is greater on Daudi cells (12,700 binding sites/cell) than AU937 cells (3,300 binding sites/cell); however, their receptor affinities were similar. Component o, which exhibited high antiproliferative activity on both cell lines, had low affinity for the IFN-alpha 2b binding site on AU937 and Daudi cells. Several human IFN-alpha s (components b', b", and e) appeared to have high affinity binding sites but low antiproliferative activity on both Daudi and AU937 cells. These data suggest that there may be more than one binding site or receptor for human IFN-alpha, and/or there may be a multicomponent receptor involved in the biological actions of these molecules.
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Affiliation(s)
- R Hu
- Division of Cytokine Biology, Food and Drug Administration, Bethesda, Maryland 20892
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1347
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Hu R, Wilber RG. Anterior cervical corpectomy for the treatment of complex cervical lesions. Can J Surg 1993; 36:85-8. [PMID: 8443725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Instability and stenosis of the cervical spine have been treated by posterior decompression and anterior decompression with fusion. In this study the authors evaluate the results obtained in 31 patients who underwent anterior cervical corpectomy for compressive or unstable lesions of the cervical spine. Operative level, preoperative and postoperative symptoms and physical findings were assessed. Twenty-seven patients had preoperative neurologic symptoms and signs, including alterations in sensation, motor findings and reflexes. The average follow-up was 12 months, average number of disc spaces excised was 2.5 and average number of vertebral bodies excised was 1.6. With respect to relief of pain, results were good or excellent in 27 patients. All patients but one had union of the bone graft. No neurologic deterioration occurred. The authors believe that patients with compressive lesions of the cervical spine can benefit from anterior cervical corpectomy with fusion and that complications are minimal.
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Affiliation(s)
- R Hu
- Department of Surgery, University of Toronto, Ont
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1348
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Hu R, Hyland KE, Mather TN. Occurrence and distribution in Rhode Island of Hunterellus hookeri (Hymenoptera: Encyrtidae), a wasp parasitoid of Ixodes dammini. J Med Entomol 1993; 30:277-280. [PMID: 8433338 DOI: 10.1093/jmedent/30.1.277] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The wasp Hunterellus hookeri Howard parasitizes several species of ixodid ticks including Ixodes dammini Spielman, Clifford, Piesman & Corwin, the vector of Lyme disease spirochetes, Borrelia burgdorferi, in the northeastern United States. We detected the occurrence and evaluated the distribution of this wasp parasitoid in populations of I. dammini in Rhode Island. There has been no intentional introduction of a tick parasitoid recorded anywhere in Rhode Island; yet, we found this wasp at one of the six study sites (Prudence Island), where it parasitized 21 (n = 243) and 17% (n = 284) of nymphal I. dammini collected during 1988 and 1989, respectively. The proportion of nymphs parasitized was greatest during May (46%) and was less in June (18%), July (18%), and August (11%). In Rhode Island, the wasp was only found parasitizing ticks at the site with the highest (by a factor of 2) tick population, confirming similar observations in Massachusetts and New York. It is suggested that establishment as well as the distribution of H. hookeri depends upon a super abundant deer tick population. The usefulness of this parasitoid as a biological control agent is yet unknown.
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Affiliation(s)
- R Hu
- Department of Zoology, University of Rhode Island, Kingston 02881
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Hu R, Egami T, Tsai A, Inoue A, Masumoto T. Atomic structure of quasicrystalline Al65Ru15Cu20. Phys Rev B Condens Matter 1992; 46:6105-6114. [PMID: 10002294 DOI: 10.1103/physrevb.46.6105] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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1350
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Hu R, Wilber RG. Drill sleeve for pedicle screw fixation. Orthop Rev 1992; 21:783, 787. [PMID: 1614727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Pedicle screw fixation is a popular method of fixation of the spine. Placement of screw and prevention of injury are surgeon dependent. We describe an easily made drill sleeve and depth gauge to assist in the preparation of the vertebral pedicle for pedicle screw application. Use of this device will help prevent soft tissue injury and overpenetration of the drill in the vertebral body.
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Affiliation(s)
- R Hu
- University of Manitoba, Health Sciences Centre, Winnipeg, Canada
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