Nitric oxide in vPAG mediates the depressor response to acupuncture in stress-induced hypertensive rats

The hypertensive rat model was made by chronic stress of electric foot-shocks and noises. On such hypertensive rats, when anesthetized with urethane and chloralose, the electroacupuncture (EA) to bilateral "Zusanli (st.36)" acupoints for 20 min, could result in a depressor (including both systolic and diastolic pressure) and bradycardiac response as well as an attenuation in the maximum of left ventricular pressure, end diastolic pressure and +/-dp/dt. In power spectrum analysis of heart rate variability aspect, EA could increase all total variance, very low frequency component, low frequency component and the ratio of low frequency component and high frequency component. When EA with microinjection of N(omega) - Nitro- L-Arginine , a blocker of the formation of nitric oxide, into the ventral periaqueductal gray matter (vPAG), the above effects of EA were abolished or reduced significantly. The results suggest that the depressor effect of EA on stress-induced hypertensive rats might be mediated by nitric oxide in the vPAG due to activation of sympathetic inhibitory system and by attenuated cardiac activities.

On-eye evaluation of optical performance of rigid and soft contact lenses

A Shack-Hartmann aberrometer was used to assess the optical performances of eyes corrected with rigid or soft contact lenses compared with spectacles. Metrics of optical quality derived from the measured wave aberrations were consistent with the subjective rating of visual clarity by subjects. Optical aberration analysis illustrated the differences in aberration structures of eyes wearing different optical corrections. For our subjects, correction with a rigid gas-permeable lens yielded significantly better optical quality than did the soft contact lens or spectacle lens. This was due to a reduction in the eye's asymmetric (odd-order) aberrations and a reduction in the amount of the eye's positive spherical aberration. These observations can be explained by theoretical calculations of the aberrations of the eye plus lens optical system. We conclude that aberrometry provides a better understanding of the optical effects of contact lenses in situ and could be useful for optimizing future designs of contact lenses.

Use of a Shack-Hartmann aberrometer to assess the optical outcome of corneal transplantation in a keratoconic eye

We report the optical outcome of corneal transplantation treatment on a keratoconic eye as measured with a Shack-Hartmann aberrometer, and we compare the results with the recovery of visual acuity after surgery. Before surgery, the naked keratoconic eye exhibited extremely large aberrations that could not be measured unless the patient wore a rigid gas-permeable contact lens. With the lens, the computed point-spread function of the eye was large and multimodal, and simulated retinal images confirmed the patient's subjective report of multiple, overlapping images. After full recovery from surgery, aberrations of the corrected eye were much smaller compared with the presurgical eye, which implied a more compact point-spread function and clearer retinal images. These optical changes were mirrored by an improvement in uncorrected visual acuity from 1.3 logarithm of the minimum angle of resolution (logMAR) before surgery to 0 logMAR with spectacle correction after full recovery. We conclude that the Shack-Hartmann aberrometer provides an objective, quantitative assessment of the optical outcome of penetrating keratoplasty that allows the clinician to measure retinal image quality objectively and to accurately simulate the complex visual distortions associated with keratoconus.

Role and regulation of activation of caspases in cisplatin-induced injury to renal tubular epithelial cells

BACKGROUND

Cellular and molecular mechanisms responsible for cisplatin-induced nephrotoxicity to renal tubular epithelial cells are not well understood. Although caspases play a critical role in the execution of the cell death pathway, their specific role in toxic injury to renal tubular epithelial cells has not been elucidated previously.

METHODS

The role of caspases in cisplatin-induced injury was determined using caspase inhibitors and p35 transfected LLC-PK1 cells. The Akt/PKB phosphorylation pathway was studied for the regulation of caspase activation in these cells.

RESULTS

The activation of initiator caspases-8, -9 and -2, and executioner caspase-3 began after eight hours of cisplatin treatment, thereafter markedly increased in a time (8 to 24 hours) and dose-dependent manner (0 to 200 micromol/L). Proinflammatory caspase-1 did not show cisplatin-induced activation. Inhibition of caspase-3 by over expressing cowpox virus p35 protein or alternatively by the peptide inhibitor DEVD-CHO provided marked protection against cell death and partial protection against DNA damage. We then examined the role of the Akt/PKB phosphorylation pathway in regulation of cisplatin-induced caspase activation. There was a marked induction of Akt/PKB phosphorylation in a time (0 to 8 hours) and dose-dependent (0 to 200 micromol/L) manner during the course of cisplatin injury. Cisplatin-induced Akt/PKB activation was associated with Bad phosphorylation, suggesting induction of a cell survival signal mediated by the Bcl-2 family member, Bad. Wortmannin or LY294002, two structurally dissimilar inhibitors of phosphatidylinositol 3'-kinase (PI-3 kinase), abolished both cisplatin-induced Akt phosphorylation and Bad phosphorylation, and promoted cisplatin-induced early and accelerated activation of caspase-3 and caspase-9, but not of caspase-8 and caspase-1, indicating that inhibition of the Akt/PKB phosphorylation pathway enhances the mitochondrial-dependent activation of caspases. The impact of enhanced activation of caspases by wortmannin or LY294002 was reflected on accelerated cisplatin-induced cell death.

CONCLUSIONS

These studies demonstrate differential activation and role of caspases in cisplatin injury, and provide the first evidence of cisplatin-induced induction of the Akt/PKB phosphorylation pathway, inhibition of which enhances activation of caspase-3 and caspase-9.

[A case-control study of endogenous estrogen and risk of Alzheimer's disease]

OBJECTIVE

To investigate the risk of Alzheimer's disease (AD) associated with endogenous estrogen.

METHODS

A population based, m: n matched case-control study was conducted, including 115 female AD patients identified from sample population aged 55 years or older as cases and 1,041 non-cognitive impairment individuals from same population matched for age and sex as controls.

RESULTS

Age at natural menopause had significant effect on AD using multivariate analysis. The odds ratio (OR) for AD was 0.672 for individuals whose age at natural menopause were between 47 to 50 years old, compared with individuals whose age at menopause were less than 47 years old. The OR was 0.452 for individuals whose age at menopause were more than 50 years old comparing with individuals whose age at menopause were less than 47 years old (P = 0.0207). The OR for AD increased parallel to the increase of age at menarche (adjusted OR = 1.160 for each increased year, P = 0.0342).

CONCLUSION

The decrease of endogenous level in postmenopausal women might serve an etiological factor for AD.

[Design of multi-channel EEG collection system for stereoscopic VEP and study of the VEP evoked by binocular disparity]

A multi-channel EEG collection system has been constructed for visual evoked potentials (VEP) studies, using IBM compatible PC and clinical EEG amplifier. The collection system not only is suitable for investigative and clinical use, but also works perfectly in the EEG collection and signal processing of stereoscopic VEP. The characters of the depth related VEP evoked by binocular disparity were identified after analysing and comparing the VEP superposition results. The partial results of the VEP extraction are in accord with the previous studies. The system serves as a helpful tool in studies of stereoscopic cognition and brain function.

Linkage of body mass index to chromosome 20 in Utah pedigrees

Several linkage studies have hinted at the existence of an obesity predisposition locus on chromosome 20, but none of these studies has produced conclusive results. Therefore, we analyzed 48 genetic markers on chromosome 20 for linkage to severe obesity (BMI> or =35) in 103 extended Utah pedigrees (1,711 individuals), all of which had strong aggregation of severe obesity. A simple dominant model produced a maximum multipoint heterogeneity LOD score of 3.5 at D20S438 (55.1 cM). Two additional analyses were performed. First, a one-gene, two-mutation model (with one dominant mutation and one recessive mutation) increased the LOD score to 4.2. Second, a two-locus model (with one locus dominant and one recessive) generated a multipoint LOD score of 4.9. We conclude that one or more severe obesity predisposing genes lie within an interval of approx. 10 cM on chromosome 20. This study generated significant LOD scores which confirm suggestive linkage reports from previous studies. In addition, our analyses suggest that the predisposing gene(s) is localized very near the chromosome 20 centromere.

Graft survival in a rhesus renal transplant model after immunotoxin-mediated T-cell depletion is enhanced by mycophenolate and steroids

BACKGROUND

Anti-CD3 immunotoxin (IT), a T-cell-depleting agent, prolongs survival of renal allografts in a rhesus monkey model without the need for long-term immunosuppression. In this study we sought to further prolong allograft survival by giving short-term conventional immunosuppression simultaneous with IT administration.

METHODS

MHC class II mismatched, juvenile rhesus monkeys were paired as donor and recipient for renal transplantation. Recipients received two to three daily doses of IT starting on the day of transplantation. Additional immunosuppression was given for no more than 60 days. Graft function was monitored by serum creatinine and renal biopsies. Flow cytometry was used to monitor T-cell recovery.

RESULTS

Graft survival time (GST) in animals receiving IT was prolonged compared with controls with 50% of IT-treated monkeys surviving >100 days. Animals treated with IT plus mycophenolate mofetil (MMF) and steroids had significantly enhanced GST (mean GST, 305 days) compared with those treated with IT alone (mean GST, 94 days). In contrast, addition of cyclosporine or 40-O-[2-Hydroxyethyl]rapamycin did not significantly increase graft survival time. A comparison among animals from all treatment groups with short (<100 days) and long (>100 days) GST demonstrated that those with the shorter GST had a higher blood T-cell count 2 weeks after transplantation. Full recovery of CD4+ T cells required longer than 6 months.

CONCLUSIONS

A combination with MMF and steroids given for 4 days after renal allograft transplantation significantly increases GST in IT-treated monkeys. We hypothesize that MMF and steroids suppress the initial T-cell activation mediated by IT.

[An analysis on the forearm bone mass density of rural female and the environmental risk factors]

The distribution of distal and proximal forearm bone mass densities (BMD) with age was discribed and the environmental risk factors of rural female analyzed. A group of 1432 rural female aged 15 and over were sellected. Their demographic characteristics, living and eating habit were obtained by standardized questionnaire. The distal and proximal forearm bone mass density were measured by peripheral dual-energy X ray absorptionmetry (pDEXA). The results showed that the distal and proximal forearm BMDs were increased with age before age 25 and 30 respectively, and reached the peak value at age 30-35. The distal forearm bone density decreased significantly at age 40 while the proximal forearm BMD decreased at age 45. Bone loss rate of the two bone sites was increased significantly at age 50 and reached the peak value at age 55-60. Only the the density of proximal forearm bone, and the year of menopause was the main cause of low bone density. Body weight was the positive factor for bone density at age less than 60. Height only positively affected the proximal forearm bone of those at age 30-45. More ever, drinking tea, parity and educational status may affect distal forearm bone in certain age group while parity, educational status, occupation and marital status were possible risk factors of proximal forearm BMD. It is concluded that environmental risk factors of BMD varied with bone site and age. The prevention of low BMD must rely on subject's age and bone site. The surveillance of low bone density must put the emphasis on spony bone.

CSN3 interacts with IKKgamma and inhibits TNF- but not IL-1-induced NF-kappaB activation

The transcription factor nuclear factor kappaB (NF-kappaB) plays a pivotal role in immune and inflammatory responses. Activation of NF-kappaB requires the activity of IKK, a kinase complex that contains two catalytic subunits, IKKalpha and IKKbeta, and a regulatory subunit IKKgamma. To understand how IKK activity is regulated, we searched for IKKgamma-interacting proteins by the yeast two-hybrid system. These screenings identified CSN3, a component of the COP9 signalsome, as a protein specifically interacting with IKKgamma. Overexpression of CSN3 inhibits NF-kappaB activation triggered by tumor necrosis factor (TNF), but not interleukin-1 (IL-1). Moreover, overexpression of CSN3 also inhibits NF-kappaB activation triggered by proteins involved in TNF signaling, including TNF-R1, TRAF2, RIP, and NIK, but not by TRAF6, a protein involved in IL-1 signaling. These data suggest that CSN3 is a specific negative regulator of TNF- but not IL-1-induced NF-kappaB activation pathways.

[Expression of a human FL eukaryotic expressing plasmid mediated by lipofectamine in HFCL cells]

AIM

Bone marrow stromal cell line-HFCL were transfected with the recombinant eukaryotic expressing vector-pIRESlneo/hFL by using liposome-mediated gene transfer method and get a stable expression.

METHODS

HFCL cells were transfected with the recombinant eukaryotic expressing vector-pIRESlneo/hFL by using liposome lipofectamine. Integration of hFL in the genome, transcription of hFL mRNA and expression of hFL protein in the transfected HFCL cells were assayed by Southern blot, Northern blot, Western blot and ELISA, the experiment of the human umbilical blood CD34+ cell multiplication.

RESULTS

hFL cDNA was integrated into HFCL genome successfully, hFL mRNA was transcripted, hFL protein was expressed with (60.3 +/- 0.1) ng. 10(6) cell(-1) x d(-1) and the experiment of the human umbilical blood CD34+ cell multiplication shows that hFL has obvious biological activity in the supernatant.

CONCLUSION

The recombinant plasmid is proved to be stably expressed in HFCL cells and obvious biological activity of hFL was detectable in the supernatant of the transfected cells.

EXAFS measurements for liquid Ge-Si alloys

EXAFS measurements around the Ge-K edge have been carried out for liquid Ge-Si alloys for the first time to investigate the local structure around a Ge atom. To perform the EXAFS measurements for the liquid alloys with high melting temperatures, a new sapphire cell have been developed. The measurements were carried out for the liquid alloys from 10% to 60% of Si and the crystalline ones from 10% to 70% of Si as a reference. EXAFS oscillations, x(k), are observed even at 1480 degrees C for liquid Ge(0.4)Si(0.6). The position of the first peak in the radial distribution function obtained from Fourier transform of x(k) is shifted towards smaller distance for liquid and crystalline alloys with increasing Si concentration. The results of a curve-fit analysis in a harmonic approximation show that Ge-Ge and Ge-Si bonds in the liquid alloys become long with increasing Si concentration while those become slightly short in the crystaline ones.

[The change of vWF in vascular endothelial cells under different stress]

AIM

To correlate the injury of vascular endothelial cells during various pathological conditions with the change of vWF (von Willebrand Factor) in different VEC lines.

METHODS

Flow cytometer(FCM) were used to defect the immunoflourescent stained vWF in pulmonary artery endothelial cells (PAEC) of pig and aortic endothelial cells(AEC) of rats.

RESULTS

The positive rates of vWF in PAEC of pigs is similar with that in AEC of rats under normal condition, but it decreased differently after hypoxic or cold injury. It was very interesting that the mean fluorescence intensity of positive PAEC or AEC exposed to hypoxia or cold elevated significantly compared with those of control.

CONCLUSIONS

The change of vWF in VEC can be used to evaluate the function of VEC under different stress.

Increased glomerular deposits of von Willebrand factor in chronic, but not acute, rejection of primate renal allografts

BACKGROUND

In our previously described primate renal allograft model, T cell ablation leads to long-term graft survival. The role of endothelial cell alteration in chronic rejection was examined in our model.

METHODS

Renal transplants were performed in rhesus monkeys using a T cell- depleting immunotoxin, FN18-CRM9. Sections from 10 rejected kidneys (5 acute and 7 chronic rejection) were examined after immunohistochemical staining for expression of endothelium-related proteins [von Willebrand factor (vWF), CD62P, and CD31], fibrinogen, and a macrophage marker (CD68). Glomerular staining for each antigen was graded on a semiquantitative scale.

RESULTS

Intense staining for vWF was consistently observed in glomerular endothelium, subendothelium, and mesangium in all kidneys removed due to chronic rejection. vWF staining was weak in kidneys showing acute rejection. The difference in glomerular staining was statistically significant. Staining for vWF in extraglomerular vessels was nearly identical in kidneys showing acute and chronic rejection. Expression of CD62P was increased in extraglomerular vessels in allografts with chronic rejection, but the glomeruli showed little or no staining. There was no significant difference in the glomerular staining for CD62P or CD31 in organs showing acute and chronic rejection. Fibrinogen staining of glomerular mesangium was seen in kidneys with chronic rejection. Macrophages (CD68+) infiltrating glomeruli were more numerous in kidneys showing chronic rejection.

CONCLUSION

Increased glomerular deposition of vWF in renal allografts showing chronic rejection, without increased staining for CD62P or CD31, suggests increased constitutive secretion of vWF from endothelial cells as a component of the mechanism of chronic rejection in our model.

Longitudinal Evaluation of Optical Aberrations Following Laser in situ Keratomileusis Surgery

Objective measurements of the optical aberrations of an eye were taken with a Shack-Hartmann aberrometer immediately before, immediately after, and at regular intervals over a two month recovery period following LASIK refractive surgery. Results indicate that the surgery induced large amounts of positive spherical aberration which regressed slightly during recovery. Computed point-spread functions for various pupil diameters indicate that retinal image quality was the same before and after surgery for small and medium sized pupils (<4 mm diameter) but was significantly degraded for large pupils (>4 mm).

Nuclear apoptosis induced by isolated mitochondria

We isolated and purified mitochondria from mouse livers and spinach leaves. When added into egg extracts of Xenopus laevis, they caused nuclei of mouse liver to undergo apoptotic changes. Chromatin condensation, margination and DNA ladder were observed. After incubating isolated mitochondria in some hypotonic solutions, and centrifuging these mixtures at high speed, we got mitochondrial supernatants. It was found that in the absence of cytosolic factor, the supernatant alone was able to induce apoptotic changes in nuclei. The effective components were partly of protein. DNA fragmentation was partly inhibited by caspase inhibitors AC-DEVD-CHO and AC-YVAD-CHO. Meanwhile, caspase inhibitors fully blocked chromatin condensation. Primary characterization of the nuclear endonuclease(s) induced by mitochondrial supernatants was also conducted. It was found that this endonuclease is different from endonuclease G, cytochrome c-induced nuclease, or Ca2+-activated endonuclease.

Chemical constituents of two Chinese Magnoliaceae plants, Tsoongiodendron odorum and Manglietiastrum sinicum, and their inhibition of platelet aggregation

Phytochemical investigations of Tsoongiodendron odorum and Manglietiastrum sinicum, both Magnoliaceae, led to the isolation of twenty compounds in total. Among them, one was a new sesquiterpene, 11-O-oleoyl-beta-eudesmol (2), and another, 1-(3,4-dimethoxypheny)-4-(3,4-methylenedioxyphenyl)-2,3-dimethy lbutane (12) was isolated as a natural product for the first time. Moreover, 13C-NMR spectral data of isoguaiacin (16) are reported here for the first time. Structure elucidations for compounds reported here were mainly based on their spectral data. The ethanolic extracts of T. odorum and M. sinicum, and six pure compounds, 4(15)-eudesmen-11-ol (beta-eudesmol) (1), 1 beta-hydroxy-4(15),11(13)-eudesmadien-12,6 alpha-olide (reynosin) (3), 3,11(13)-eudesmadien-12,6 alpha-olide (alpha-cyclocostunolide) (5), erythro-1-(4-hydroxy-3-methoxyphenyl)-4-(3,4-methylenedioxyphenyl)-2,3- dimethylbutane (11), nectandrin-B (18), and syringaresinol (19), displayed considerable inhibition against platelet aggregation induced by AA, by ADP, or by PAF.

Ceramides induce apoptosis in HeLa cells and enhance cytochrome c-induced apoptosis in Xenopus egg extracts

Ceramide has been reported to induce typical apoptotic changes in nuclei incubated in a cell-free system, and that the addition of ceramide bypasses the requirement for mitochondria. Here, we explore the possible pathways by which ceramide induces apoptosis either in intact cells or in a cell-free system which we have developed. We found that in the cell-free system, C2-ceramide is not able to induce apoptosis in nuclei whereas cytochrome c does, but it is able to induce HeLa cells to undergo apoptosis. Ceramide is also not able to induce apoptosis when added into the cell-free system together with purified mitochondria. Further investigation showed that C2-ceramide at certain concentrations greatly increases nuclear apoptosis caused by cytochrome c in the cell-free system. From these results we conclude that the induction of apoptosis by ceramide may require intact cells in which some unknown signal transduction pathways are involved.

[Retroviral transduction of a mutant erbB-2 gene into human CD34+ derived dendritic cells]

OBJECTIVE

To successfully transduce a mutant erbB-2 gene into normal human CD34(+)-derived dendritic cells (DCs) and verify gene expression in these transduced dendritic cells.

METHODS

The packaging cell line PA317 was transfected with mutant erbB-2 gene DNA and the virus produced was used to infect packaging cell line PG13. The virus produced by PG13 was used to infect CD34(+)-derived dendritic cells by the spinoculation method using flasks coated with fibronectin material to facilitate retrovirus gene transter efficiency and the mutant erbB-2 gene expression was assessed by ABC staining and FACScan methods.

RESULTS

A mutant erbB-2 gene packaging cell line was produced and this mutant gene was transduced into human CD34(+)-derived DCs. It was verified that the relatively large numbers of the transduced DCs expressed the mutant erbB-2 protein which was eradicated of the ability to transform mouse NIH3T3 fibroblast cells.

CONCLUSIONS

Human DCs can be gene-modified and these gene-modified DCs may be useful in stimulating T lymphocytes for immunotherapy.

Intratumoral injection with [(188)Re]rhenium sulfide suspension for treatment of transplanted human liver carcinoma in nude mice

Hepatocellular carcinoma (HCC) is one of the most common malignancies in China. Direct intratumoral injection of nonremovable radioactive material has been widely studied because it could deliver high doses of radiation to target sites and minimize radiation leakage to non-target organs or tissues. Thirty nude mice bearing SMMC 7721 human liver carcinoma were used for the biodistribution study after intratumoral injection of [(188)Re]rhenium sulfide suspension or sodium [(188)Re]perrhenate solution. Another 30 tumor-bearing mice were divided into six groups, four groups of which were treated with a 0.1 ml [(188)Re]rhenium sulfide suspension at doses of 3.7, 7.4, 18.5, 29.6 MBq by a single intratumoral injection. For control studies, to study the tumor inhibiting ratio, the remaining two groups were injected with nonradioactive rhenium sulfide suspension and Hanks' balanced salt solution, respectively. The injections were repeated 6 days later. The retention percentages of radioactivity (%ID) in tumors injected with [(188)Re]rhenium sulfide suspension were 90.96+/-6.63%, 86.09+/-22.58% and 87.62+/-13.97% at 1, 24 and 48 h, respectively. Tumor inhibition ratios are as high as 89% when the outer space of tumor (0.5-0.6 cm from center) received about 507.6 Gy doses. Intratumoral injection of [(188)Re]rhenium sulfide suspension results in high tumor retention indicating this approach has strong potential for the treatment of hepatic carcinoma.

[Epidemiological characteristics of Guillain-Barré syndrome in urban and rural areas in Beijing and Hebei, China]

OBJECTIVE

To investigate epidemiological and clinical patterns of Guillain-Barré syndrome (GBS) in urban and rural areas in Beijing municipality and Hebei province, China.

METHODS

We investigated GBS incidence using a strengthened case surveillance and an active case ascertainment in 2 counties and 4 districts of Beijing municipality and 3 counties of Hebei province during 1993 to 1994.

RESULTS

On the basis of the diagnostic criteria of NINCDS, 54 patients were identified. The age-adjusted incidence rates per 100,000 population for GBS were 0.9 in rural areas, and 0.8 in urban areas. A peak agespecific incidence showed in adults aged 50 to 59 years. A higher incidence appeared to occur in the spring and summer for rural residents, but not significant for urban population. In comparing course of GBS in rural and urban areas, there were differences in mean days from beginning of neurological symptom to maximal weakness (4.3 vs 7.6 days), and from symptom onset to beginning of recession (11.8 vs 17.5 days). There were preceding events in 72% patients, most frequently in respiratory infection, sensory disturbance in 70.9%, and respiratory assistance in 7.6%. The outcome was compatible with other reports; with complete recovery at 12 months in 79.2% and minimal residua in 20.8% for those alive and with casefatality rate in 7.4%. In addition, a follow-up study on electrophysiological features in 19(90.5%) patients from two counties of Beijing showed the demyelinating lesion (89.5%) over the axonal lesion (52.6%) of motor and/or sensory nerves.

CONCLUSIONS

The epidemiological and clinical characteristics of GBS were similar to that reported in other countries. Demyelinating GBS was the main pattern in present population-based study.

Structural revision of four spiramine diterpenoid alkaloids from the roots of Spiraea japonica

On the basis of detailed 1H-NMR 13C-NMR spectral analysis, especially by 2D NMR experiments (1H-1H COSY, HMQC, HMBC, and NOESY) as well as by chemical transformations. four isoatisine type diterpenoid alkaloids, spiramines P and Q, and U and T, have been reassigned as the 6beta hydroxyl and 6beta acetoxyl substituents, respectively, rather than the previously assigned 15alpha counterparts in our further studies on chemical constituents of the roots of Spiraea japonica var. acuta.

Cytochrome c release and caspase activation during menadione-induced apoptosis in plants

We report here the detection of the release of cytochrome c from mitochondria into the cytosol during menadione-induced apoptosis in tobacco protoplasts. Western blot analysis indicated that the caspase specific inhibitors AC-DEVD-CHO (Ac-Asp-Glu-Val-Asp-aldehyde) and AC-YVAD-CHO (N-acetyl-Try-Val-Ala-aspartinal) inhibited the degradation of a caspase 3 specific substrate PARP (poly(ADP-ribose) polymerase), and they had no effect on the release of cytochrome c. Further study showed that menadione could not induce apoptosis of mouse liver nuclei in tobacco cytosol extract containing no mitochondria. However, when cytochrome c or mitochondria was added into the cytosol extract, apoptosis of mouse liver nuclei and the degradation of PARP could both be detected. The results provide strong evidence that menadione can induce apoptosis in tobacco protoplasts via the release of cytochrome c from mitochondria into the cytosol.

Clinical applications of the Shack-Hartmann aberrometer

The efficacy of the Shack-Hartmann technique for measuring the optical aberrations of the eye was evaluated for four classes of clinical conditions associated with optically abnormal eyes. These categories (with specific examples) are: anomalies of the tear film (dry eye), corneal disease (keratoconus), corneal refractive surgery [laser-assisted in situ keratomileusis (LASIK)], and lenticular cataract. We show that in each of these cases, it is possible to obtain at least a partial topographic map of the refractive aberrations of the patient's eyes, but severe losses of data integrity can occur. We further show that the Shack-Hartmann aberrometer provides additional information about the eye's imperfections on a very fine spatial scale (< 0.4 mm) which scatter light and further degrade the quality of the retinal image. Taken together, spatial maps of the variation of optical aberrations and scatter across the eye's entrance pupil represents an improved description of the optical imperfections of the abnormal eye.

Design and synthesis of novel dihydropyridine alpha-1a antagonists

A series of analogs of SNAP 5150 containing heteroatoms at C2 or C6 positions is described. Herein, we report that the presence of alkyl substituted heteroatoms at the C2(6)-positions of the dihydropyridine are well tolerated. In addition, 15 inhibited the phenylephrine induced contraction of dog prostate tissue with a Kb of 1.5 nM and showed a Kb (DBP, dogs, microg/kg)/Kb (IUP, dogs, microg/kg) ratio of 14.8/2.5.

Autologous high-killing cytotoxic T lymphocytes against human lung cancer are induced using interleukin (IL)-1beta, IL-2, IL-4, and IL-6: possible involvement of dendritic cells

Although CTLs bear main immune responses in human tumors, stable CTL clones against human lung cancer have rarely been generated. Our previous study demonstrated efficient autologous CTL induction in human gastric cancer and glioblastoma by cytokine combination of interleukin (IL)-1beta (167 IU/ml), IL-2 (67 IU/ml), IL-4 (67 IU/ml), and IL-6 (134 IU/ml). In this study, we demonstrated successful induction of autologous stable CTLs in five of six patients with lung adenocarcinoma from mixed-lymphocyte tumor culture using this cytokine combination. All CTLs revealed potent and specific killing activity against autologous target cells (over 75% in CD8+ CTLs and over 50% in CD4+ CTLs at an E:T ratio of 10 for 24 h). Using a series of antibodies, CD8+ CTLs showed to recognize tumor-specific antigens of lung cancer cells through HLA class I. In the separate experiments, failure of CTL induction from monocyte-depleted peripheral blood mononuclear cells and appearance of cells with characteristics of dendritic cells from adherent peripheral blood mononuclear cells in the culture of the same concentration of IL-1beta, IL-4, and IL-6 indicated that CTLs can be efficiently generated by this cytokine combination via possible dendritic cell induction. This is the first study of an efficient and reproducible in vitro CTL induction against human lung cancer.

Fast scan and echo planar MR imaging technology

The development of imaging technology for acquiring ever-faster images has been an ongoing activity since the early years of MR imaging development. This article gives the reader a sense of the range of technical challenges faced by the developers of faster imaging hardware and some of their solutions. Before reviewing the technical issues, however, the authors briefly discuss the marketplace realities that have led to technology decisions and, to a certain extent, the prolonged pace of development of the hardware.

Identification and characterization of the human orthologue of yeast Pex14p

Pex14p is a central component of the peroxisomal protein import machinery, which has been suggested to provide the point of convergence for PTS1- and PTS2-dependent protein import in yeast cells. Here we describe the identification of a human peroxisome-associated protein (HsPex14p) which shows significant similarity to the yeast Pex14p. HsPex14p is a carbonate-resistant peroxisomal membrane protein with its C terminus exposed to the cytosol. The N terminus of the protein is not accessible to exogenously added antibodies or protease and thus might protrude into the peroxisomal lumen. HsPex14p overexpression leads to the decoration of tubular structures and mislocalization of peroxisomal catalase to the cytosol. HsPex14p binds the cytosolic receptor for the peroxisomal targeting signal 1 (PTS1), a result consistent with a function as a membrane receptor in peroxisomal protein import. Homo-oligomerization of HsPex14p or interaction of the protein with the PTS2-receptor or HsPex13p was not observed. This distinguishes the human Pex14p from its counterpart in yeast cells and thus supports recent data suggesting that not all aspects of peroxisomal protein import are conserved between yeasts and humans. The role of HsPex14p in mammalian peroxisome biogenesis makes HsPEX14 a candidate PBD gene for being responsible for an unrecognized complementation group of human peroxisome biogenesis disorders.

Design and synthesis of novel alpha1a adrenoceptor-selective dihydropyridine antagonists for the treatment of benign prostatic hyperplasia

We report the synthesis and evaluation of novel alpha1a adrenoceptor subtype-selective antagonists. Systematic modification of the lipophilic 4,4-diphenylpiperidinyl moiety of the dihydropyridine derivatives 1 and 2 provided several highly selective and potent alpha1a antagonists. From this series, we identified the 4-(methoxycarbonyl)-4-phenylpiperidine analogue SNAP 5540 (-) [(-)-63] for further characterization. When examined in an isolated human prostate tissue assay, this compound was found to have a Ki of 2.8 nM, in agreement with the cloned human receptor binding data (Ki = 2.42 nM). Further evaluation of the compound in isolated dog prostate tissue showed a Ki of 3.6 nM and confirmed it to be a potent antagonist (Kb = 1.6 nM). In vivo, this compound effectively blocked the phenylephrine-stimulated increase in intraurethral pressure (IUP) in mongrel dogs, at doses which did not significantly affect the arterial pressure (diastolic blood pressure, DBP), with a DBP Kb/IUP Kb ratio of 16. In addition, (-)-63 also showed greater than 40 000-fold selectivity over the rat L-type calcium channel and 200-fold selectivity over several G protein-coupled receptors, including histamine and serotonin subtypes. These findings prove that alpha1a adrenoceptor-subtype selective antagonists such as (-)-63 may be developed as uroselective agents for an improved treatment of BPH over nonselective alpha1 antagonists such as prazosin and terazosin, with fewer side effects.

Modulation of alloimmunity to major histocompatibility complex class I by cotransfer of cytokine genes in vivo

Major histocompatibility complex (MHC) class I antigen is a potent stimulus for alloimmune responses and is the principal immunologic target mediating acute cellular rejection of allografts. Using a method of direct in vivo gene transfer of cDNA encoding donor type MHC class I, we showed in a rat model that recipient muscle could express the transferred MHC class I cDNA, resulting in alloimmunization of the recipient. This was most graphically demonstrated by accelerated rejection of cardiac allografts expressing the same MHC class I as encoded by the immunizing cDNA. We now report the use of the particle-mediated gene transfer via a gene gun (Geneva, Middleton, WI, USA) to transfer MHC class I, as well as cytokine gene expression vectors, into rat skin. Compared to intramuscular injection, gene gun transfer to skin resulted in more efficient immunization. Donor-specific cytotoxic T lymphocyte (CTL) responsiveness and antibody levels increased. Furthermore, coexpression of certain cytokine genes with the MHC class I cDNA modulated the immune response. Specifically, coimmunization with IL-10 cDNA abrogated immunity to allo-MHC class I, while coimmunization with GM-CSF cDNA enhanced it. The influence of expression of these genes in skin was demonstrated by alteration of donor cardiac allograft survival. This model is useful for induction and modulation of alloimmune responses and may be used to develop gene therapy strategies to modify them.

Role of enhanced ceramide generation in DNA damage and cell death in chemical hypoxic injury to LLC-PK1 cells

BACKGROUND

Ceramide has been implicated to be a second messenger in the cell signaling pathway involved in cell growth, proliferation, and apoptotic cell death. However, there is little information of a role of ceramide in DNA damage and cell death in hypoxic injury known to induce necrotic cell death.

METHODS

Ceramide generation was measured in LLC-PK1 cells exposed to chemical hypoxia with a mitochondrial electron transport inhibitor, antimycin A and glucose deprivation. The effect of inhibition of ceramide generation on chemical hypoxia-induced DNA damage and cell death and the effect of exogenous ceramide on cellular injury were also determined.

RESULTS

Chemical hypoxia resulted in a rapid increase in ceramide production prior to any evidence of DNA damage and cell death in LLC-PK1 cells. The inhibitor of ceramide synthase, fumonisin B1, provided a marked protection against chemical hypoxia-induced DNA strand breaks, DNA fragmentation and cell death. Fumonisin B1 did not affect adenosine triphosphate (ATP) depletion induced by antimycin A, suggesting that fumonisin B1 does not alter cellular uptake of antimycin A. We confirmed the ability of ceramide synthase inhibitor, fumonisin B1, to suppress chemical hypoxia-induced ceramide generation. Exposure of LLC-PK1 cells to synthetic ceramide, C2- and C6-ceramide, but not C2-dihydroceramide, the structural analog of C2-ceramide, resulted in DNA strand breaks, DNA fragmentation and cell death in a dose- and time-dependent manner similar to the effect of chemical hypoxia.

CONCLUSIONS

Our data indicate that ceramide is a key modulator for DNA damage and cell death in chemical hypoxia to renal tubular epithelial cells.

Primate renal transplants using immunotoxin

BACKGROUND

T-lymphocyte depletion 7 days before transplantation with immunotoxin FN 18-CRM9 has resulted in tolerance to subsequent renal allografts. We tested the effect of giving immunotoxin on the day of the transplantation and evaluated its effect on rhesus monkey and allograft survival, on antibody production, and on T-cell recovery.

METHODS

Major histocompatibility complex mismatched renal allografts were performed in rhesus monkeys. Immunotoxin was given starting on the day of transplantation, with and without prednisone and mycophenolate mofetil for 3 days. T-cell subsets and alloantibody levels were measured by flow cytometry. The ability of treated monkeys to develop antibody to tetanus, diphtheria, and xenoantibody was measured. Histology of renal transplants was read in a blinded manner.

RESULTS

Immunotoxin started on the day of transplantation resulted in prolonged allograft survival in all treatment groups. Graft loss between days 50 and 135 was most often due to interstitial nephritis. Later graft loss was due to chronic rejection. Monkeys had intact antibody responses to alloantigen, tetanus, diphtheria, and xenoantibody. Their CD4 cells recovered gradually over 6 months.

CONCLUSIONS

Immunotoxin reliably prolongs renal allograft survival when started on the day of transplantation, but interstitial nephritis and chronic rejection limit the development of long-term tolerance. T-cell-dependent B-cell responses remain intact after treatment.

Analysis of primate renal allografts after T-cell depletion with anti-CD3-CRM9

BACKGROUND

FN18-CRM9 is a CD3-specific immunotoxin that is capable of depleting CD3+ T cells. Pretreatment of rhesus monkeys with this agent before transplantation can induce donor-specific tolerance and "split tolerance" to renal allografts.

METHODS

Heterotopic renal transplants were performed on monkeys that received posttransplant FN18-CRM9. Histological and immunohistological staining, as well as analysis of the intragraft cytokine profile by reverse transcriptase polymerase chain reaction, was performed on percutaneous allograft biopsies.

RESULTS

Experimental monkeys had significant prolongation of allograft survival. Although an interstitial, mononuclear cell infiltrate was seen in all of the renal transplants, there was minimal evidence of acute cellular rejection. Histological evidence of alloantibody-mediated damage was detected 3 to 5 months after transplantation in the monkeys treated with FN18-CRM9. Immunohistology demonstrated the reappearance of CD3+ and CD4+ T cells, as well as CD20+ B cells, in the grafts. Cytokine analysis demonstrated expression of interferon-gamma. An intact anti-donor IgG response was seen.

CONCLUSION

Treatment of monkeys with FN18-CRM9 immediately after transplantation significantly prolongs renal allograft survival. Allograft biopsies demonstrate a lack of acute cellular rejection; however, alloantibody-mediated graft damage and rejection occur, with an intact anti-donor IgG response. The intragraft expression of the interferon-gamma may reflect this ongoing humoral rejection. These data suggest that even a brief period of T-cell allosensitization may lead to humorally mediated allograft damage. Efforts to achieve tolerance with posttransplant FN18-CRM9 will require modification of the protocol to deplete T cells before allosensitization exposure or to supplement the posttransplant immunomodification strategy.

Identification of a dihydropyridine as a potent alpha1a adrenoceptor-selective antagonist that inhibits phenylephrine-induced contraction of the human prostate

A number of novel dihydropyridine derivatives based upon 1, 4-dihydro-3-(methoxycarbonyl)-2, 6-dimethyl-4-(4-nitrophenyl)-5-((3-(4, 4-diphenylpiperidin-1-yl)propyl)aminocarbonyl)pyridine (4) have been synthesized and tested at cloned human alpha adrenoceptors as well as the rat L-type calcium channel. Within this compound series, 5-(aminocarbonyl)-1,4-dihydro-2, 6-dimethyl-4-(4-nitrophenyl)-3-((3-(4, 4-diphenylpiperidin-1-yl)propyl)aminocarbonyl)pyridine (19) displayed good binding affinity and selectivity for the alpha1a adrenoceptor (pKi = 8.73) and potently inhibited (pA2 = 9.23) phenylephrine-induced contraction of the human prostate.

[Evaluation of the intubating conditions and maintenance doses of rocuronium]

OBJECTIVE

To assess intubating conditions after administration of rocuronium 0.6 mg/kg at 60 or 90 s and neuromuscular blocking effects of rocuronium.

METHODS

Thirty-two patients were randomly designated to two groups: 60 s group and 90 s group. Anesthesia consisted of thiopentone, fentanyl, N2O/O2 and enflurane. After a 2 x ED95 dose the trachea was intubated at 60 or 90 s and the intubating conditions were recorded. After intubation was finished, patients were allocated randomly to receive either intravenous infusion or bolus injection of rocuronium to maintain surgical relaxation.

RESULTS

Intubating conditions were not different between the two groups and were found to be clinically acceptable (good or excellent) in all patients. The maintenance of surgical relaxation was satisfactory either with repeated bolus and infusion of rocuronium.

CONCLUSION

Intubation can be performed under good to excellent conditions within 60-90 seconds after a bolus dose of 0.6 mg/kg rocuronium. This indicates that rocuronium may be a suitable alternative to succinycholine during rapid-sequence induction of anesthesia.

Dual-orthogonal radial basis function networks for nonlinear time series prediction

A new structure of Radial Basis Function (RBF) neural network called the Dual-orthogonal RBF Network (DRBF) is introduced for nonlinear time series prediction. The hidden nodes of a conventional RBF network compare the Euclidean distance between the network input vector and the centres, and the node responses are radially symmetrical. But in time series prediction where the system input vectors are lagged system outputs, which are usually highly correlated, the Euclidean distance measure may not be appropriate. The DRBF network modifies the distance metric by introducing a classification function which is based on the estimation data set. Training the DRBF networks consists of two stages. Learning the classification related basis functions and the important input nodes, followed by selecting the regressors and learning the weights of the hidden nodes. In both cases, a forward Orthogonal Least Squares (OLS) selection procedure is applied, initially to select the important input nodes and then to select the important centres. Simulation results of single-step and multi-step ahead predictions over a test data set are included to demonstrate the effectiveness of the new approach.

CTLA4-Ig and anti-CD40 ligand prevent renal allograft rejection in primates

Selective inhibition of T cell costimulation using the B7-specific fusion protein CTLA4-Ig has been shown to induce long-term allograft survival in rodents. Antibodies preventing the interaction between CD40 and its T cell-based ligand CD154 (CD40L) have been shown in rodents to act synergistically with CTLA4-Ig. It has thus been hypothesized that these agents might be capable of inducing long-term acceptance of allografted tissues in primates. To test this hypothesis in a relevant preclinical model, CTLA4-Ig and the CD40L-specific monoclonal antibody 5C8 were tested in rhesus monkeys. Both agents effectively inhibited rhesus mixed lymphocyte reactions, but the combination was 100 times more effective than either drug alone. Renal allografts were transplanted into nephectomized rhesus monkeys shown to be disparate at major histocompatibility complex class I and class II loci. Control animals rejected in 5-8 days. Brief induction doses of CTLA4-Ig or 5C8 alone significantly prolonged rejection-free survival (20-98 days). Two of four animals treated with both agents experienced extended (>150 days) rejection-free allograft survival. Two animals treated with 5C8 alone and one animal treated with both 5C8 and CTLA4-Ig experienced late, biopsy-proven rejection, but a repeat course of their induction regimen successfully restored normal graft function. Neither drug affected peripheral T cell or B cell counts. There were no clinically evident side effects or rejections during treatment. We conclude that CTLA4-Ig and 5C8 can both prevent and reverse acute allograft rejection, significantly prolonging the survival of major histocompatibility complex-mismatched renal allografts in primates without the need for chronic immunosuppression.

Direct MHC class I complementary DNA transfer to thymus induces donor-specific unresponsiveness, which involves multiple immunologic mechanisms

Our purposes were 1) to determine whether direct transfer of cDNA encoding allogeneic MHC class I Ag to the rat thymus would be capable of inducing donor-specific unresponsiveness and 2) to study the immunologic mechanism of this effect. Plasmid DNA encoding donor strain (ACI-RT1.Aa) MHC class I Ag was directly injected into Lewis (RT1(l)) rat recipient thymus 7 to 10 days before ACI liver transplantation. A single dose of anti-lymphocyte serum was given i.p. on the day of thymic injection. Rats injected intrathymically with plasmid DNA and treated with anti-lymphocyte serum demonstrated prolonged survival in 9 of 13 rats (&gt;100 days). PCR was used to demonstrate that RT1.Aa cDNA was expressed in thymus transiently and later appeared in spleen. CTL limiting dilution assays showed that CTL precursor frequency was decreased in tolerant liver recipients. To test the hypothesis of clonal deletion vs anergy, CTL limiting dilution assays cultures were restimulated with donor cells and IL-2 to reverse anergy. Restimulation caused CTL precursor frequency to return to near normal in only one of five tolerant rats, suggesting clonal deletion or a dense anergic state. Passive transfer of splenocytes from tolerant rats to naive recipients prolonged cardiac allograft survival, suggesting that suppressor-type cells may also contribute to thymic tolerance in our model. In summary, our data suggest that donor MHC class I Ag expressed in thymus by direct DNA injection, followed by liver allografting, results in donor-specific unresponsiveness. The mechanism of this effect is complex, involving multiple immunologic mechanisms.

Direct MHC class I complementary DNA transfer to thymus induces donor-specific unresponsiveness, which involves multiple immunologic mechanisms

Our purposes were 1) to determine whether direct transfer of cDNA encoding allogeneic MHC class I Ag to the rat thymus would be capable of inducing donor-specific unresponsiveness and 2) to study the immunologic mechanism of this effect. Plasmid DNA encoding donor strain (ACI-RT1.Aa) MHC class I Ag was directly injected into Lewis (RT1(l)) rat recipient thymus 7 to 10 days before ACI liver transplantation. A single dose of anti-lymphocyte serum was given i.p. on the day of thymic injection. Rats injected intrathymically with plasmid DNA and treated with anti-lymphocyte serum demonstrated prolonged survival in 9 of 13 rats (>100 days). PCR was used to demonstrate that RT1.Aa cDNA was expressed in thymus transiently and later appeared in spleen. CTL limiting dilution assays showed that CTL precursor frequency was decreased in tolerant liver recipients. To test the hypothesis of clonal deletion vs anergy, CTL limiting dilution assays cultures were restimulated with donor cells and IL-2 to reverse anergy. Restimulation caused CTL precursor frequency to return to near normal in only one of five tolerant rats, suggesting clonal deletion or a dense anergic state. Passive transfer of splenocytes from tolerant rats to naive recipients prolonged cardiac allograft survival, suggesting that suppressor-type cells may also contribute to thymic tolerance in our model. In summary, our data suggest that donor MHC class I Ag expressed in thymus by direct DNA injection, followed by liver allografting, results in donor-specific unresponsiveness. The mechanism of this effect is complex, involving multiple immunologic mechanisms.