Therapeutic Application of Dendrobium fimbriatum Hook for Retinopathy Caused by Ultraviolet Radiation and Chemotherapy Using ARPE-19 Cells and Mouse Retina

Retinopathy caused by ultraviolet radiation and cancer chemotherapy has increased dramatically in humans due to rapid environmental and social changes. Therefore, it is very important to develop therapeutic strategies to effectively alleviate retinopathy. In China, people often choose dendrobium to improve their eyesight. In this study, we explored how Dendrobium fimbriatum extract (DFE) protects ARPE-19 cells and mouse retinal tissue from damage of ultraviolet (UV) radiation and chemotherapy. We evaluated the antioxidant capacity of DFE using the 1,1-diphenyl-2-trinitophenylhydrazine (DPPH) assay. The protective effects of DEF from UV- and oxaliplatin (OXA)-induced damage were examined in ARPE-19 cells using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and immunofluorescence (IF) stains, and in mouse retinal tissue using immunohistochemistry (IHC) stains. Our results show that DFE has excellent antioxidant capacity. The ARPE-19 cell viability was decreased and the F-actin cytoskeleton structure was damaged by UV radiation and OXA chemotherapy, but both were alleviated after the DFE treatment. Furthermore, DFE treatment can alleviate OXA chemotherapy-induced reduced expressions of rhodopsin and SOD2 and increased expressions of TNF-α and caspase 3 in mouse retinal tissue. Thus, we suggest that DFE can act as suitable treatment for retinopathy through reducing oxidative stress, inflammation, and apoptosis.

Alleviating Effects of Ovatodiolide and Antcin K Supplements on High-Fat Diet-Induced Cardiovascular Dysfunction in ApoE-Knockout Mice by Attenuating Oxidative Stress

A high-fat diet (HFD) is a major risk factor for cardiovascular diseases. Many pure compounds have been demonstrated to be effective in treating cardiovascular diseases. In this study, we investigated the alleviating effects of oral ovatodiolide and antcin K (OAK) supplements on HFD-induced cardiovascular dysfunction in apolipoprotein E (ApoE)-knockout mice. Cardiovascular dysfunction was induced in ApoE-knockout mice by feeding them an HFD for 12 weeks. The degree of cardiovascular dysfunction was assessed through echocardiography, hematological and biochemical analyses, and immunofluorescence and immunohistochemical staining. The HFD-fed mice exhibited cardiovascular dysfunction-abnormal blood biochemical index. The arterial wall tissue exhibited the marked deposition of lipids, upregulated expression of vascular cell adhesion molecule-1 and CD36 receptors, and downregulated expression of the ABCA1 receptor. Macrophages isolated from the peritoneal cavity of the mice exhibited increased levels of lipid accumulation, reactive oxygen species, and CD11b expression but reduced mitochondrial membrane potential. The expression of superoxide dismutase 2 was downregulated and that of tumor necrosis factor-α was upregulated in the myocardial tissue. Oral OAK supplements twice a day for 12 weeks significantly mitigated HFD-induced cardiovascular dysfunction in the experimental mice. Oral OAK supplements appear to be a promising strategy for treating HFD-induced cardiovascular dysfunction. The underlying mechanisms may involve the reduction of lipid accumulation in the artery and oxidative stress and inflammation in the cardiovascular tissue.

Therapeutic Effects of Plant Extracts of Anoectochilus roxburghii on Side Effects of Chemotherapy in BALB/c Breast Cancer Mice

Breast cancer is the most common cancer in women, and chemotherapy is an effective treatment. However, chemotherapy often causes adverse side effects such as cardiotoxicity, myelosuppression, immunodeficiency, and osteoporosis. Our study focused on the alleviating effects of Anoectochilus roxburghii extracts (AREs) on the adverse side effects of chemotherapy in mice with breast cancer. We individually evaluated the antioxidant capacity and cytotoxicity of the AREs using DPPH and MTT assays. We also examined the effects of the AREs on intracellular F-actin, reactive oxygen species (ROS), and the mitochondrial membrane potential (MMP) of 4T1 cancer cells before and after doxorubicin (DOX) treatment. Our results showed that ARE treatment enhanced the effects of DOX chemotherapy by promoting cell morphology damage, oxidative stress, and ROS generation, as well as by reducing MMP in the 4T1 breast cancer cells. By using BALB/c mice with breast cancer with DOX treatment, our results showed that the DOX treatment reduced body weight, blood pressure, and heart rate and induced myelosuppression, immunodeficiency, cardiotoxicity, and osteoporosis. After oral ARE treatment of BALB/c mice with breast cancer, the chemotherapeutic effects of DOX were enhanced, and the adverse side effects of DOX chemotherapy were alleviated. Based on the above results, we suggest that AREs can be used as an adjuvant reliever to DOX chemotherapy in BALB/c mice with breast cancer.

Botanical Antcin K Alleviates High-Fat Damage in Palm Acid Oil-Treated Vascular Endothelial Cells and Macrophages

Lipid metabolism disorder is the most critical risk factor for atherosclerosis, and the process involves lipid deposition in the arterial intima. In Taiwan, antcin K, an active triterpenoid from the fruiting bodies of Antrodia camphorata, has been considered a potential lipid-lowering agent. Despite this, the possible therapeutic mechanisms of antcin K remain unclear. To explore the crucial role of botanical antcin K in reducing atherosclerotic plaque, we used SVEC4-10 vascular endothelial cells and RAW264.7 macrophages with palm acid oil-induced high-fat damage as our cell models. Our results showed through using the DPPH assay that antcin K had excellent free radical scavenging ability. Antcin K treatment can significantly alleviate the high-fat damage and reduce the levels of inflammatory factors of TNF-α and IL-1β in vascular endothelial cells and macrophages, as shown through MTT assay and ELISA. Furthermore, antcin K treatment can effectively enhance migration ability and clear lipid deposition in macrophages, as shown by using cell migration assay and oil red O staining. When stained with immunofluorescence, antcin K was shown to significantly decrease the expression of adhesion molecules of vascular cell adhesion molecule 1 (VCAM-1) in vascular endothelial cells involved in monocyte migration and inflammation. Antcin K not only reduced the expression of the CD36 scavenger receptor but also augmented the expression of Kruppel-like factor 4 (KLF4) transcription factor in macrophages, which inhibits the transformation of macrophages into foam cells underlying the pathological process of atherosclerosis. Taking our findings into account, we suggested that botanical antcin K could have therapeutic potential for the treatment of atherosclerosis.

Applications of Immunomagnetic Reduction Technology as a Biosensor in Therapeutic Evaluation of Chinese Herbal Medicine in Tauopathy Alleviation of an AD Drosophila Model

Alzheimer's disease (AD) is the most common form of dementia. The most convincing biomarkers in the blood for AD are currently β-amyloid (Aβ) and Tau protein because amyloid plaques and neurofibrillary tangles are pathological hallmarks in the brains of patients with AD. The development of assay technologies in diagnosing early-stage AD is very important. The study of human AD subjects is hindered by ethical and technical limitations. Thus, many studies have therefore turned to AD animal models, such as Drosophila melanogaster, to explore AD pathology. However, AD biomarkers such as Aβ and p-Tau protein in Drosophilamelanogaster occur at extremely low levels and are difficult to detect precisely. In this study, we applied the immunomagnetic reduction (IMR) technology of nanoparticles for the detection of p-Tau expressions in hTau^R406W flies, an AD Drosophila model. Furthermore, we used IMR technology as a biosensor in the therapeutic evaluation of Chinese herbal medicines in hTau^R406W flies with Tau-induced toxicity. To uncover the pathogenic pathway and identify therapeutic interventions of Chinese herbal medicines in Tau-induced toxicity, we modeled tauopathy in the notum of hTau^R406W flies. Our IMR data showed that the selected Chinese herbal medicines can significantly reduce p-Tau expressions in hTau^R406W flies. Using evidence of notal bristle quantification and Western blotting analysis, we confirmed the validity of the IMR data. Thus, we suggest that IMR can serve as a new tool for measuring tauopathy and therapeutic evaluation of Chinese herbal medicine in an AD Drosophila model.

Neurotherapy of Yi-Gan-San, a Traditional Herbal Medicine, in an Alzheimer's Disease Model of Drosophila melanogaster by Alleviating Aβ42 Expression

Alzheimer's disease (AD), a main cause of dementia, is the most common neurodegenerative disease that is related to the abnormal accumulation of amyloid β (Aβ) proteins. Yi-Gan-San (YGS), a traditional herbal medicine, has been used for the management of neurodegenerative disorders and for the treatment of neurosis, insomnia and dementia. The aim of this study was to examine antioxidant capacity and cytotoxicity of YGS treatment by using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays in vitro. We explored neuroprotective effects of YGS treatment in alleviating Aβ neurotoxicity of Drosophila melanogaster in vivo by comparing survival rate, climbing index, and Aβ expressions through retinal green fluorescent protein (GFP) expression, highly sensitive immunomagnetic reduction (IMR) and Western blotting assays. In the in vitro study, our results showed that scavenging activities of free radical and SH-SY5Y nerve cell viability were increased significantly (p < 0.01-0.05). In the in vivo study, Aβ₄₂-expressing flies (Aβ₄₂-GFP flies) and their WT flies (mCD8-GFP flies) were used as an animal model to examine the neurotherapeutic effects of YGS treatment. Our results showed that, in comparison with those Aβ₄₂ flies under sham treatments, Aβ₄₂ flies under YGS treatments showed a greater survival rate, better climbing speed, and lower Aβ₄₂ aggregation in Drosophila brain tissue (p < 0.01). Our findings suggest that YGS should have a beneficial alternative therapy for AD and dementia via alleviating Aβ neurotoxicity in the brain tissue.

Neurotoxicity of fipronil affects sensory and motor systems in zebrafish

Fipronil is a phenylpyrazole insecticide that may selectively inhibit gamma-aminobutyric acid receptors in insects. Although fipronil is the most widely used insecticide in aquatic environments, few studies have evaluated its neurotoxicity for the sensory and motor systems of aquatic vertebrates. We assessed the effects of acute fipronil exposure on the survival rate, number of hair cells of lateral lines, and neurotoxicity for zebrafish (Danio rerio). In addition, heat maps and the speed and distance of the swimming trajectory were compared between zebrafish subjected to the sham and fipronil treatments. Western blotting and immunohistochemistry were conducted separately to compare expressions of oxidative stress, inflammation, apoptosis, and neurotoxicity related proteins in the brain tissue between adult zebrafish with sham and fipronil treatments. Our results indicated that the survival rates and the speed and distance of the swimming trajectory significantly decreased for adult zebrafish exposed to fipronil. The results also suggested that the number of hair cells of lateral lines significantly reduced for zebrafish embryos exposed to fipronil. In histopathology and Western blotting tests, substantial oxidative stress, inflammation, and apoptosis were observed in the brain tissue of adult zebrafish exposed to fipronil. Our results revealed that fipronil toxicity may impair sensory and motor systems in zebrafish because of damage to lateral hair cells and brain tissue through oxidative stress, inflammation, and apoptosis, which in turn result in a significantly reduced survival rate and impaired locomotion. The behavioral responses of zebrafish exposed to fipronil toxicity should be determined for better understanding the reliability of behavioral biomarkers in the risk assessment of environmental toxicology.

Application of digital holographic tomography in antitumor effect of cantharides complex on 4T1 breast cancer cells

The study focuses on a methodology providing noninvasive monitoring and evaluation of the antitumor effect of traditional Chinese medicine, cantharides complex (canth), on 4T1 breast tumor cells. Digital holographic tomography (DHT) and developed data post-processing algorithms were used for quantitative estimation of changes in optical and morphological parameters of cells. We calculated and compared data on the refractive index, thickness, and projected area of 4T1 breast tumor cells in control untreated specimens and those treated with doxorubicin hydrochloride (DOX), canth, and their combinations. Post-treatment changes in cellular morphology recorded by DHT demonstrated that the two drugs led to noticeably different morphological changes in cells that can be presumably associated with different pathways of their death, apoptosis, or necrosis. The effect of combined treatment with these two drugs strongly depended on their relative concentrations and could lead to changes characteristic either for DOX or for canth; however, being more profound than those obtained when using each drug solely. The results obtained by DHT are in a good correspondence with commonly used cell viability analysis and immunofluorescent analysis of changes in cellular cytoskeleton.

MPTP toxicity causes vocal, auditory, orientation and movement defects in the echolocation bat

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) can damage dopaminergic neurons in the substantia nigra in many mammals with biochemical and cellular changes that are relatively similar to those observed in Parkinson's disease. Our study examined whether MPTP-treated echolocation bats can cause changes in bat echolocation system. By considering ultrasound spectrums, auditory brainstem-evoked potentials and flight trajectories of normal bats, we observed that the vocal, auditory, orientation and movement functions of MPTP-treated bats were significantly impaired, and they exhibited various symptoms resembling those in patients with Parkinson's disease. Our immunohistochemistry and western blot analyses further indicated that expression of vocal-related FOXP2 in the superior colliculus, auditory-related otoferlin in the inferior colliculus, dopamine synthesis-related aromatic l-amino acid decarboxylase in the substantia nigra and dopamine receptor in the striatum was significantly decreased. Furthermore, protein expression related to inflammation, oxidative stress and apoptosis in the substantia nigra was significantly increased in MPTP-treated bats. These results indicate that inflammation, oxidative stress and apoptosis may be instrumental in dopaminergic neurodegeneration in the substantia nigra. The vocal, auditory and orientation and movement dysfunctions of MPTP-treated bats are relatively consistent with symptoms of Parkinson's disease.

Effects of imidacloprid, a neonicotinoid insecticide, on the echolocation system of insectivorous bats

Imidacloprid, a widely used neonicotinoid insecticide, has led to a decline in the honey bee population worldwide. An invertebrate insect prey with neonicotinoid toxicity can adversely affect insectivores, such as echolocating bats. The aim of the current study was to examined whether imidacloprid toxicity may interfere echolocation system such as vocal, auditory, orientation, and spatial memory systems in the insectivorous bat. By comparing the ultrasound spectrum, auditory brainstem-evoked potential, and flight trajectory, we found that imidacloprid toxicity may interfere functions in vocal, auditory, orientation, and spatial memory system of insectivorous bats (Hipposideros armiger terasensis). As suggested from immunohistochemistry and western blots evidences, we found that insectivorous bats after suffering imidacloprid toxicity may decrease vocal-related FOXP2 expressions in the superior colliculus, auditory-related prestin expressions in the cochlea, and the auditory-related otoferlin expressions in the cochlea and the inferior colliculus, and cause inflammation and mitochondrial dysfunction-related apoptosis in the hippocampal CA1 and medial entorhinal cortex. These results may provide a reasonable explanation about imidacloprid-induced interference of echolocation system in insectivorous bats.

Organic anion-transporting polypeptide 1B3 as a dual reporter gene for fluorescence and magnetic resonance imaging

Reporter proteins have broad applications in visualizing molecular events at the cellular, tissue and whole-body levels. Transmembrane transporters recognizing specific molecular domains are of particular interest because they enable the migration of signal-source molecules from the extracellular space to the cytoplasm for subsequent application in multimodality imaging. Organic anion-transporting polypeptides (OATPs) have demonstrated their MRI reporter efficacy. We further expanded their use as a dual-modality reporter in MRI and noninvasive in vivo imaging system (IVIS). We overexpressed OATP1B3 in the HT-1080 sarcoma cell line. Both Gd-EOB-DTPA, an MRI contrast agent, and indocyanine green (ICG), a near-infrared fluorescent dye that provides better deep-tissue detection because of its long wavelength, could be delivered to the intracellular space and imaged in a tumor-bearing nude mouse model. Our in vivo dual-imaging reporter system achieved high sensitivity in MRI and observation periods lasting as long as 96 h in IVIS. Because of the superior temporal and spatial resolutions and the clinical availability of both ICG and Gd-EOB-DTPA, this dual-imaging OATP1B3 system will find biomedical use in tumor biology, stem cell trafficking, and tissue engineering.—Wu, M.-R., Liu, H.-M., Lu, C.-W., Shen, W.-H., Lin, I.-J., Liao, L.-W., Huang, Y.-Y., Shieh, M.-J., Hsiao, J.-K. Organic anion-transporting polypeptide 1B3 as a dual reporter gene for fluorescence and magnetic resonance imaging.

Characterization of an iron oxide nanoparticle labelling and MRI-based protocol for inducing human mesenchymal stem cells into neural-like cells

The aim of the current study was to develop an iron oxide nanoparticle (ION) labelling and magnetic resonance imaging (MRI)-based protocol to allow visualization of the differentiation process of mesenchymal stem cells (MSCs) into neural-like cells (NCs) in vitro. Ferucarbotran, a clinically available ION, which can be visualized under MRI, is used for tracking cells implanted in vivo. The NCs were verified morphologically and histologically by light microscopy, and their functions were verified by measuring their action potentials. Conformational conversion of axon-like structures was observed under light microscopy. These NCs exhibited frequent, active action potentials compared with cells that did not undergo neural differentiation. The labelling of ION had no influence on the morphological and functional differentiation capacity of the MSCs. We conclude that the MSCs that were differentiated into NCs exhibited in vitro activity potential firing and may be used to replace damaged neurons.

Cytogenetic evaluation of cataract patients occupationally exposed to ionizing radiation in northeast China

Long-term radiation exposure is hazardous to health; late-onset effects of exposure to ionizing radiation (IR) pose risks to the lens, and are associated with other non-cancerous diseases. Individuals occupationally exposed to low-dose IR are prone to developing eye cataracts. Cytogenetic evaluations suggest that IR is associated with chromosomal aberrations in occupationally exposed individuals. However, data regarding the association between chromosomal aberrations in cataract patients and occupational exposure to IR is scarce. Therefore, we aimed to report the characteristics of chromosomal aberrations in cataract patients from a Chinese population, occupationally exposed to IR. We found that the average age and frequency of numerical chromosomal aberrations were significantly lower in the exposed patients as compared with that in the non-exposed patients. In addition, the frequencies of dicentric and acentric chromosomes were significantly higher in the exposed patients as compared with those in the non-exposed patients. Therefore, chronic occupational exposure to IR affects cataract development in the Chinese population. The age of cataract patients exposed to IR was significantly lower than the age of cataract onset in normal individuals. Based on this study, we suggest that there is an urgent need for improved radiation safety and eye protection in individuals exposed to IR in the work place.

Sperm quality and DNA damage in men from Jilin Province, China, who are occupationally exposed to ionizing radiation

Long-term radiation exposure affects human health. Ionizing radiation has long been known to raise the risk of cancer. In addition to high doses of radiation, low-dose ionizing radiation might increase the risk of cardiovascular disease, lens opacity, and some other non-cancerous diseases. Low- and high-dose exposures to ionizing radiation elicit different signaling events at the molecular level, and may involve different response mechanisms. The health risks arising from exposure to low doses of ionizing radiation should be re-evaluated. Health workers exposed to ionizing radiation experience low-dose radiation and have an increased risk of hematological malignancies. Reproductive function is sensitive to changes in the physical environment, including ionizing radiation. However, data is scarce regarding the association between occupational radiation exposure and risk to human fertility. Sperm DNA integrity is a functional parameter of male fertility evaluation. Hence, we aimed to report sperm quality and DNA damage in men from Jilin Province, China, who were occupationally exposed to ionizing radiation. Sperm motility and normal morphology were significantly lower in the exposed compared with the non-exposed men. There was no statistically significant difference in sperm concentration between exposed and non-exposed men. The sperm DNA fragmentation index was significantly higher in the exposed than the non-exposed men. Chronic long-term exposure to low doses of ionizing radiation could affect sperm motility, normal morphology, and the sperm DNA fragmentation index in the Chinese population. Sperm quality and DNA integrity are functional parameters that could be used to evaluate occupational exposure to ionizing radiation.

Two New Species of the Genus Xistra Bolivar (Orthoptera: Tetrigidae) from China

Two new species of the tetrigid genus Xistra Bolivar from China, namely Xistra oculata Li, Deng et Zheng n. sp. and Xistra brachynota Li, Deng et Zheng n. sp. are described. An updated key to all known species of the genus is given.

MAGNETIC NANOPARTICLE LABELING OF CULTURED CANCER CELL LINE WITHOUT TRANSFECTION AGENT

Magnetic nanoparticle (MNP) labeling of stem cell has been proved its efficacy for cell trafficking. Most of the labeling technique requires mixture of iron oxide nanoparticles and transfection agent. Stem cells with ionic MNP without the aid of transfection agent were labeled previously. The possibility of high efficiency labeling of cultured cancer cell, HeLa cell, by using ionic MNP is proposed. The labeled cell morphology was observed and the intracellular iron content was determined by spectrophotometry. The cell character change was evaluated by flow cytometry where front scattering count and side scattering count (SSC) were recorded. The imaging ability of the labeling method was determined by T2 weighted magnetic resonance (MR) imaging. Labeled MNPs were accumulated at cytoplasm is observed and the iron content of labeled cell could reach 27 pg/cell. There is no cell diameter change but the cell granularity increased according to SSC data from flow cytometry. Under clinical 1.5T MR imaging, we could detect labeled cells easily were detected at the cell number of 1 × 105. It is concluded that labeling of cancer cell with ionic MNPs without transfection agent is an efficient labeling method which will provide non-invasive imaging method for monitoring cancer behavior.

Combination of IFNγ and chemotherapeutic agents increase TRAIL sensitivity of neuroblastoma cell lines

OBJECTIVE

Aim of the study was to further evaluate the role of caspase 8 and death receptors (DR) in the TRAIL-induced apoptosis of neuroblastoma (NB) cell lines.

METHODS

Caspase 8 mRNA expression was monitored by RT-PCR. Caspase 8, DR5 and DR4 protein expression were monitored by Western blot analysis. The effects of IFNγ, TRAIL, IFNγ+TRAIL, caspase 8 inhibitor+TRAIL and IFNγ+chemotherapeutic agents+TRAIL on the growth and apoptosis of NB cells were detected with MTT and flow cytometry. The relative caspase 8 activity was measured with colorimetric assay.

RESULTS

Caspase 8 expression was induced by IFNγ in the NB cell line SKNDZ. TRAIL alone did not induce apoptosis compared with controls but a combination of IFNγ+TRAIL and IFNγ+chemotherapeutic agents+TRAIL significantly induced cell apoptosis in SY5Y cells. Etoposide and doxorubicin induced DR5 but not DR4 in NB cell lines. SKNDZ cells expressing caspase 8 after treatment with IFNγ were still resistant to TRAIL but sensitive to TRAIL after the induction of DR5.

CONCLUSIONS

Sensitization of NB cells to TRAIL may be mediated by the upregulation of caspase 8 with IFNγ and DR5 with chemotherapeutic agents. This suggests that caspase 8 and death receptors play a very important role in TRAIL-induced apoptosis of NB cells and a combination of IFNγ, TRAIL and chemotherapeutic agents may be a new and interesting anticancer treatment strategy for NB.

Mechanism of cellular uptake and impact of ferucarbotran on macrophage physiology

Superparamagnetic iron oxide (SPIO) nanoparticles are contrast agents used for magnetic resonance imaging. Ferucarbotran is a clinically approved SPIO-coated carboxydextran with a diameter of about 45–60 nm. We investigated the mechanism of cellular uptake of Ferucarbotran with a cell model using the murine macrophage cell line Raw 264.7. We observed a dose-dependent uptake of these SPIO particles by spectrophotometer analysis and also a dose-dependent increase in the granularity of the macrophages as determined by flow cytometry. There was a linear correlation between the side scattering mean value and iron content (P<0.001, R² = 0. 8048). For evaluation of the endocytotic pathway of these ingested SPIO particles, different inhibitors of the endocytotic pathways were employed. There was a significant decrease of side scattering counts in the cells and a less significant change in signal intensity based on magnetic resonance in the phenylarsine oxide-treated macrophages. After labeling with SPIO particles, the macrophages showed an increase in the production of reactive oxygen species at 2, 24, and 48 h; a decrease in mitochondrial membrane potential at 24 h; and an increase in cell proliferation at 24 h. We concluded that Ferucarbotran was internalized into macrophages via the clathrin-mediated pathway and can change the cellular behavior of these cells after labeling.

In vivo magnetic resonance imaging of cell tropism, trafficking mechanism, and therapeutic impact of human mesenchymal stem cells in a murine glioma model

Stem cells have offered much promise as delivery vehicles for brain tumor therapy, with the development of modalities to track the tumor tropism of stem cells receiving intense focus. Cellular magnetic resonance imaging (MRI) allows serial high-resolution in vivo detection of transplanted stem cells' tropism toward gliomas in the mouse brain once these cells are internally labeled with iron oxide particles, but has been impeded by low labeling efficiencies. In this study, we describe the use of ferucarbotran and protamine (Fer-Pro) complexes for labeling human mesenchymal stem cells (hMSCs) for MRI tracking of glioma tropism in vivo. We found that Fer-Pro was not toxic and was highly efficient for labeling in vitro. Cell labeling with Fer-Pro promoted the migration of hMSCs toward glioma U87MG cells in vitro, which was mediated by stromal-derived factor-1/CXCR4 (SDF-1/CXCR4) signaling. Fer-Pro-labeled hMSCs could migrate specifically toward gliomas in vivo, which was observed with a clinical 1.5-T MRI system. The efficient labeling of Fer-Pro also allowed a tropic mechanism mediated by SDF-1/CXCR4 signaling to be detected by MRI in vivo. Additionally, the potential intrinsic inhibitory effect of hMSCs on glioma progression was estimated simultaneously. This is the first report to have used a clinical MRI modality to simultaneously study the migration, the therapeutic impact on tumors, and above all the trafficking mechanism of bone marrow-derived mesenchymal stem cells from human in a murine glioma xenograft model. The use of Fer-Pro for stem cell labeling may have potential clinical applications in stem cell guided therapy.

Mesoporous silica nanoparticles improve magnetic labeling efficiency in human stem cells

Tumblerlike magnetic/fluorescein isothiocyanate (FITC)-labeled mesoporous silica nanoparticles, Mag-Dye@MSNs, have been developed, which are composed of silica-coated core-shell superparamagnetic iron oxide (SPIO@SiO(2)) nanoparticles co-condensed with FITC-incorporated mesoporous silica. Mag-Dye@MSNs can label human mesenchymal stem cells (hMSCs) through endocytosis efficiently for magnetic resonance imaging (MRI) in vitro and in vivo, as manifested by using a clinical 1.5-T MRI system with requirements of simultaneous low incubation dosage of iron, low detection cell numbers, and short incubation time. Labeled hMSCs are unaffected in their viability, proliferation, and differentiation capacities into adipocytes and osteocytes, which can still be readily detected by MRI. Moreover, a higher MRI signal intensity decrease is observed in Mag-Dye@MSN-treated cells than in SPIO@SiO(2)-treated cells. This is the first report that MCM-41-type MSNs are advantageous to cellular uptake, as manifested by a higher labeling efficiency of Mag-Dye@MSNs than SPIO@SiO(2).

The effect of surface charge on the uptake and biological function of mesoporous silica nanoparticles in 3T3-L1 cells and human mesenchymal stem cells

Cellular uptake of nanoparticles for stem cell labeling/tracking is considered as the most promising method. Recently mesoporous silica nanoparticles (MSNs) are emerging as an idea agent for efficient stem cell labeling. The objective of this study was to evaluate the effect of surface charge on the highly efficient cellular uptake and in vitro cytotoxicity of MSNs in human mesenchymal stem cells (hMSCs). The surface charge was varied by the degree of surface modification with N-trimethoxysilylpropyl-N,N,N-trimethylammonium chloride and the uptake of MSNs was detected by flow cytometry. 3T3-L1 cells were also used to compare the uptake behavior of MSNs between cell types. A clear correlation of positive surface charge and the number of fluorescence-labeled cells was mainly observed in 3T3-L1 cells. In both cells, uptake of unmodified MSNs was inhibited by phenylarsine oxide (PAO) and cytochalasin D (Cyt D) suggesting a clathrin- and an actin-dependent endocytosis were involved. With strongly positive-charged MSNs, the inhibitory effects were observed in 3T3-L1 cells but not in hMSCs. Without regard to the surface charge, uptake of MSNs into both cells did not affect their viability, proliferation, and differentiation. Our results show that MSNs uptake by hMSCs can be regulated by a threshold of positive surface charge but also imply that the modulation of surface charge on MSNs uptake is specific to cell type.

Bifunctional magnetic silica nanoparticles for highly efficient human stem cell labeling

A superparamagnetic iron oxide (SPIO) nanoparticle is emerging as an ideal probe for noninvasive cell tracking. However, its low intracellular labeling efficiency has limited the potential usage and has evoked great interest in developing new labeling strategies. We have developed fluorescein isothiocyanate (FITC)-incorporated silica-coated core-shell SPIO nanoparticles, SPIO@SiO2(FITC), with diameters of 50 nm, as a bifunctionally magnetic vector that can efficiently label human mesenchymal stem cells (hMSCs), via clathrin- and actin-dependent endocytosis with subsequent intracellular localization in late endosomes/lysosomes. The uptake process displays a time- and dose-dependent behavior. In our system, SPIO@SiO2(FITC) nanoparticles induce sufficient cell MRI contrast at an incubation dosage as low as 0.5 microg of iron/mL of culture medium with 1.2x105 hMSCs, and the in vitro detection threshold of cell number is about 1x104 cells. Furthermore, 1.2x105 labeled cells can also be MRI-detected in a subcutaneous model in vivo. Labeled hMSCs are unaffected in their viability, proliferation, and differentiation capacities into adipocytes and osteocytes which can still be readily MRI detected. This is the first report that hMSCs can be efficiently labeled with MRI contrast nanoparticles and can be monitored in vitro and in vivo with a clinical 1.5-T MRI imager under low incubation concentration of iron oxide, short incubation time, and low detection cell numbers at the same time.

Functional characterization of the N termini of murine leukemia virus envelope proteins

The function of the N terminus of the murine leukemia virus (MuLV) surface (SU) protein was examined. A series of five chimeric envelope proteins (Env) were generated in which the N terminus of amphotropic 4070A was replaced by equivalent sequences from ecotropic Moloney MuLV (M-MuLV). Viral titers of these chimeras indicate that exchange with homologous sequences could be tolerated, up to V17eco/T15ampho (crossover III). Constructs encoding the first 28 amino acids (aa) of ecotropic M-MuLV resulted in Env expression and binding to the receptor; however, the virus titer was reduced 5- to 45-fold, indicating a postbinding block. Additional exchange beyond the first 28 aa of ecotropic MuLV Env resulted in defective protein expression. These N-terminal chimeras were also introduced into the AE4 chimeric Env backbone containing the amphotropic receptor binding domain joined at the hinge region to the ecotropic SU C terminus. In this backbone, introduction of the first 17 aa of the ecotropic Env protein significantly increased the titer compared to that of its parental chimera AE4, implying a functional coordination between the N terminus of SU and the C terminus of the SU and/or transmembrane proteins. These data functionally dissect the N-terminal sequence of the MuLV Env protein and identify differential effects on receptor-mediated entry.

Chylus-like urine as a complication of percutaneous hyperalimentation catheter in an infant: report of one case

A very low-birth-weight neonate developed chylus-like urine after receiving parenteral nutrition (PN) via percutaneous central venous catheters (CVC) for 7 weeks. A perirenal fluid collection could be seen under sonography. This kind of complication has not been described in literature. After withdrawing the CVC for 5 cm, the urine cleared up. For patients under prolonged PN via CVC and repeated change dressing of the CVC, close monitoring and regular evaluation of the position of the catheter tip are warranted.

Protein-tyrosine kinase and protein-serine/threonine kinase expression in human gastric cancer cell lines

Protein kinases play key roles in cellular functions. They are involved in many cellular functions including; signal transduction, cell cycle regulation, cell division, and cell differentiation. Alterations of protein kinase by gene amplification, mutation or viral factors often induce tumor formation and tumor progression toward malignancy. The identification and cloning of kinase genes can provide a better understanding of the mechanisms of tumorigenesis as well as diagnostic tools for tumor staging. In this study, we have used degenerated polymerase-chain-reaction primers according to the consensus catalytic domain motifs to amplify protein kinase genes (protein-tyrosine kinase, PTK, and protein-serine/threonine kinase, PSK) from human stomach cancer cells. Following amplification, the protein kinase molecules expressed in the gastric cancer cells were cloned into plasmid vectors for cloning and sequencing. Sequence analysis of polymerase-chain-reaction products resulted in the identification of 25 protein kinases, including two novel ones. Expression of several relevant PTK/PSK genes in gastric cancer cells and tissues was further substantiated by RT-PCR using gene-specific primers. The identification of protein kinases expressed or activated in the gastric cancer cells provide the framework to understand the oncogenic process of stomach cancer.

Paroxysmal supraventricular tachycardia in identical twins with the same left lateral accessory pathways and innocent dual atrioventricular pathways

We report on 16-year-old, female identical twins who both have atrioventricular reentrant tachycardia caused by the same left lateral atrioventricular accessory pathway. The Kent pathway in twin A was a unidirectional retrograde accessory pathway. A manifest Kent pathway was demonstrated in twin B. Both pathways were successfully ablated by radiofrequency (RF) energy and without recurrence. In addition, innocent dual AV nodal pathways were shown in both patients. These findings suggest that genetic factors may play a role in the pathogenesis of the formation of accessory atrioventricular pathways and dual AV nodal pathways.

Radiofrequency catheter ablation of tachycardia in children with and without congenital heart disease: indications and limitations

From 1993 to 1998, a total of 100 consecutive pediatric patients with tachycardia (45 male and 55 female, aged 1 year 10 months to 17 years, 11+/-4 year) who underwent electrophysiological study were reviewed. Eleven of them were younger than 5 years. Two had tachycardia-related cerebrovascular accident. Congenital heart disease was found in 12 patients. After propofol anesthesia, the clinical tachycardia could not be induced in three (two atrial tachycardia and one AV nodal re-entrant tachycardia) and became nonsustained in five (atrial tachycardia). Mechanical ablation occurred in three and two had subsequent recurrences. Among the 85 cases who received radiofrequency ablation, the overall final success rate of RF ablation for all diagnoses was 94% with a diagnosis-specific success rate ranging from 100 to 57%. Tachycardia cardiomyopathy was noted in four (three atrial tachycardia and one junctional ectopic tachycardia) and all regressed after successful ablation. Success in two patients with left posterioseptal accessory pathway could only be achieved by delivering the energy at the middle cardiac vein. Two patients with right atrial isomerism had an 'AV nodal-to-AV nodal tachycardia' which was eliminated by ablation. Total recurrence rate was 13% but final success was achieved in all during re-study except the three patients who refused re-intervention. The atrial tachycardia developed in postoperative congenital heart disease was associated with the lowest success rate (57%) and highest recurrence rate (25%). Procedure-related complications occurred in four; two with transient brachial palsy, one with first-degree AV block and one with blood loss requiring blood transfusion. In conclusion, the experience of this single center confirmed the efficacy and safety of radiofrequency catheter ablation in treating pediatric arrhythmias, but the limitations in postoperative arrhythmias and the effects of propofol on tachycardia induction (especially the atrial tachycardia) need to be improved.

Total paracentesis in non-alcoholic cirrhotics with massive ascites: mid-term effects on systemic and hepatic haemodynamics and renal function

Single total paracentesis (4.8-11 L) was performed in 23 patients with hepatitis B surface antigen (HBsAg)-positive cirrhosis and massive ascites and its effects on systemic and hepatic haemodynamics and renal function were examined over 5 days. Severe hypotension occurred in six (26.1%) patients from 6 to 54 h after paracentesis. In the remaining 17 patients, compared to the baseline, there was an increase in the cardiac output (6.1 +/- 0.3 vs 6.7 +/- 0.3 L/min, P < 0.001) and a decrease in right atrial pressure (8.8 +/- 0.8 vs 4.3 +/- 0.7 mmHg, P < 0.001), systemic vascular resistance (1160 +/- 61 vs 976 +/- 50 dyne.s.cm-5, P < 0.001), and wedged hepatic venous pressure 30 min after completion of paracentesis. After 5 days, right atrial pressure, systemic vascular resistance and wedged hepatic venous pressure returned to baseline, while the cardiac output dropped to a level lower than the baseline (5.7 +/- 0.7 L/min, P < 0.05). Hepatic venous pressure gradient had returned to baseline after 5 days. Serial tests of serum creatinine level showed an increase from day 3 (1.34 +/- 0.14 vs 1.04 +/- 0.10 mg/dL, P < 0.05). On day 5, creatinine clearance (55.7 +/- 5.4 vs 41.9 +/- 5.3 mL/min, P < 0.05) and effective renal plasma flow (351 +/- 32 vs 293 +/- 29 mL/min, P < 0.05) were decreased, compared to the baseline. Based on these data, infusion of a volume expander may be necessary for total paracentesis to avoid systemic haemodynamic complications in non-alcoholic cirrhosis.

Clinical value of tumour markers and serum-ascites albumin gradient in the diagnosis of malignancy-related ascites

To determine the clinical value of tumour markers in the diagnosis of malignancy-related ascites (not including hepatocellular carcinoma), serum and ascitic fluid levels of carcinoembryonic antigen, cancer antigen 125, carbohydrate antigen 19-9, tissue polypeptide antigen and serum-ascites albumin gradient were determined in 66 patients with cirrhotic ascites, 28 patients with hepatocellular carcinoma and ascites, and 29 patients with malignancy-related ascites. Three tumour markers and serum-ascites albumin gradient showed significant difference between patients with malignancy-related ascites and those without: serum carcinoembryonic antigen (26.4 +/- 31.5 vs 4.8 +/- 4.6 ng/mL, P < 0.01), ascitic fluid carcinoembryonic antigen (118.4 +/- 196.5 vs 2.0 +/- 1.4 ng/mL, P < 0.01), ascitic fluid carbohydrate antigen 19-9 (12,933 +/- 25,496 vs 23 +/- 67 U/mL, P < 0.01) and serum-ascites albumin gradient (1.1 +/- 0.4 vs 2.0 +/- 0.4 g/dL, P < 0.01). At the best cut-off levels chosen from near 95% of the data in those without malignancy-related ascites, the sensitivity, specificity and accuracy to diagnose malignancy-related ascites were, respectively, 65.5%, 93.6%, 87.0% using serum carcinoembryonic antigen > or = 10 ng/mL; 69.0%, 94.7%, 88.6% using ascitic fluid carcinoembryonic antigen > or = 5 ng/mL; 65.5%, 93.6%, 87.0% using ascitic fluid carbohydrate antigen 19-9 > or = 50 U/mL; 62.1%, 98.9%, 90.2% using serum-ascites albumin gradient < 1.1 g/dL. Although serum-ascites albumin gradient offered the best diagnostic accuracy and specificity, its sensitivity was not good enough. Our study indicates that serum-ascites albumin gradient and tumour markers are not sensitive parameters in the diagnosis of malignancy-related ascites.

Diagnostic parameters for spontaneous bacterial peritonitis in hepatitis B-related cirrhosis: comparison of ascitic fluid polymorphonuclear cell count, lactate and pH values

BACKGROUND

The clinical value of ascitic fluid pH or lactate in the diagnosis of spontaneous bacterial peritonitis was debated in alcoholic cirrhosis. It was rarely discussed in hepatitis B-related cirrhosis. We investigated the best rapid diagnostic method in spontaneous bacterial peritonitis of patients with hepatitis B-related cirrhosis.

METHODS

Ascitic fluid polymorphonuclear cell count, ascitic fluid pH, arterial-ascitic fluid pH gradient, ascitic fluid lactate, and arterial-ascitic fluid lactate gradient were analyzed in 79 patients with sterile portal hypertension-related ascites, 31 patients with spontaneous bacterial peritonitis, 16 patients with hepatocellular carcinoma, 15 patients with malignancy-related ascites and 9 patients with other miscellaneous diseases.

RESULTS

The sensitivity, specificity and accuracy of the diagnosis of spontaneous bacterial peritonitis were 100, 94 and 95% with the cut-off value of an ascitic fluid polymorphonuclear cell count > or = 250 cells/mm3, and were 86, 98 and 96% with that value > or = 500 cells/mm3, respectively. The sensitivity, specificity and accuracy were 29, 92, 80% using ascitic fluid pH < or = 7.35 as a cut-off value; 38, 91, 82% using arterial-ascitic fluid pH gradient > or = 0.1 as a cut-off value; 52, 92, 85% using ascitic fluid lactate > or = 32 mg/dL as a cut-off value, and 38, 96, 85% using arterial-ascitic fluid lactate gradient > or = 20 mg/dL as a cut-off value.

CONCLUSIONS

The sensitivity of ascitic fluid pH or lactate was too low to aid in a diagnosis of spontaneous bacterial peritonitis in hepatitis B-related cirrhosis in spite of the acceptable specificity. An ascitic fluid polymorphonuclear cell count > or = 250 cells/mm3 or > or = 500 cells/mm3 was the major and appropriate aids in the rapid diagnosis of spontaneous bacterial peritonitis.

Malignancy-related ascites: a diagnostic pitfall of spontaneous bacterial peritonitis by ascitic fluid polymorphonuclear cell count

To define patients with an ascitic fluid polymorphonuclear cell count > or = 250 cells/mm3 or > or = 500 cells/mm3 but without spontaneous bacterial peritonitis, 166 patients with sterile cirrhotic ascites, 46 patients with spontaneous bacterial peritonitis, 123 patients with hepatocellular carcinoma, 67 patients with peritoneal carcinomatosis or massive liver metastasis and 12 patients with other miscellaneous diseases were studied. The sensitivity, specificity and accuracy of the diagnosis of spontaneous bacterial peritonitis were 100, 86 and 88% with the cut-off value of an ascitic fluid polymorphonuclear cell count > or = 250 cells/mm3; and were 93, 91 and 92% with that value > or = 500 cells/mm3, respectively. With the cut-off value > or = 250 cells/mm3 or > or = 500 cells/mm3, the prevalence was 18% or 14% in hepatocellular carcinoma; and 30% or 19% in peritoneal carcinomatosis or massive liver metastasis. The ascitic fluid lactate concentration was insensitive and nonspecific. Among the patients with an ascitic fluid polymorphonuclear cell count greater than the cut-off values, an ascitic fluid erythrocyte count > or = 10,000 cells/mm3, a ratio of ascitic fluid erythrocyte to total leukocyte count > or = 100, and the ratio of ascitic fluid polymorphonuclear cell to total leukocyte count < or = 75% indicated hepatocellular carcinoma, while serum to ascites albumin gradient < or = 1.1 g/dl and a ratio of ascitic fluid polymorphonuclear cell to total leukocyte count < or = 75% indicated peritoneal carcinomatosis or massive liver metastasis.

A randomized controlled trial comparing octreotide and vasopressin in the control of acute esophageal variceal bleeding

This randomized controlled trial was conducted to compare the efficacy of intravenous infusion of octreotide (a synthetic long-acting somatostatin analogue) with vasopressin in 48 cirrhotic patients with endoscopically proven bleeding esophageal varices. Twenty-four patients received a continuous infusion of octreotide 25 micrograms/h for 24 h after an initial bolus of 100 micrograms and another 24 patients received a continuous infusion of vasopressin 0.4 U/min for 24 h. Bleeding was initially controlled after 6 h of drug infusion in 88% (21/24) and 54% (13/24) of the patients treated with octreotide and vasopressin respectively (p = 0.03). Complete control of bleeding after 24 h of drug infusion was achieved in 15 (63%) patients receiving octreotide and in 11 (46%) patients receiving vasopressin (p > 0.05). Side effects during drug infusion such as headache, chest pain and abdominal pain were significantly lower in the octreotide group (3/24) than in the vasopressin group (11/24). Serum gastrin and insulin levels fell significantly following octreotide infusion, but plasma glucose levels remained unchanged. Mortality related to bleeding esophageal varices was no different between the two groups. This report showed that octreotide infusion was more effective and had fewer side effects than vasopressin in initial controlling of acute esophageal variceal bleeding until an elective endoscopic sclerotherapy could be performed.

C-reactive protein and lactate dehydrogenase isoenzymes in the assessment of the prognosis of acute pancreatitis

The value of serum C-reactive protein, lactate dehydrogenase isoenzymes and erythrocyte sedimentation rate in predicting the outcome of acute pancreatitis was evaluated for 57 episodes in 54 patients. Serum C-reactive protein levels on day 2, 4 and 7 after admission were significantly higher in 19 episodes of severe attacks than in 38 episodes of mild attacks (13.71 +/- 9.68, 9.00 +/- 7.54, 6.02 +/- 3.83 vs 4.78 +/- 3.91, 3.30 +/- 3.61, 1.43 +/- 2.08 mg/dL; P less than 0.0001, P less than 0.005, P less than 0.0001, respectively). The sensitivity, specificity and accuracy of predicting a severe attack were 94, 76 and 82% using C-reactive protein greater than or equal to 8 mg/dL on day 2; 67, 92 and 84% using C-reactive protein greater than or equal to 5 mg/dL on day 7; and 59, 76 and 70% using Ranson's criteria greater than or equal to 3. Increases in LDH-4 and LDH-5 isoenzymes were found in both groups, with LDH-4 being slightly higher in severe attacks than in mild attacks. There was no significant difference of erythrocyte sedimentation rate between both groups. When compared with Ranson's criteria, lactate dehydrogenase isoenzymes and erythrocyte sedimentation rate, C-reactive protein is more valuable in the early assessment of the severity of acute pancreatitis.

Spontaneous bacterial peritonitis in patients with hepatitis B-related cirrhosis and hepatocellular carcinoma

To delineate the natural clinical course of spontaneous bacterial peritonitis in hepatitis B-related cirrhosis and to determine if it occurs in hepatocellular carcinoma, a prospective survey was conducted in 262 patients over 2 1/2 years. The in-hospital incidence and mortality rates of spontaneous bacterial peritonitis were 21.6% and 36.4%, respectively, in cirrhosis and 7.3% and 50% in hepatocellular carcinoma. In cirrhosis, the cumulative probability of annual recurrence of spontaneous bacterial peritonitis was 47.3%, which was significantly higher than the annual probability of occurrence of 11.3% in those with no previous attack (P less than 0.0001). The cumulative probability of annual survival was 27.6% in the spontaneous bacterial peritonitis patients, significantly lower than the probability of 64.0% in the control group (P = 0.0001). A univariate analysis, with Kaplan-Meier curves compared by the Mantel-Cox test, and subsequent multivariate analysis by stepwise Cox regression procedure were used to evaluate 37 variables recorded immediately after admission. Blood urea nitrogen concentration greater than 10.5 mmol/L urea (greater than 30 mg/dL) and ascitic fluid protein concentration less than 7.35 g/L (less than 735 mg/dL) were found to be the only significant predictors of lower annual survival; ascitic fluid protein concentration less than 7.50 g/L (less than 750 mg/dL) was the only significant predictor of higher annual recurrence. The authors conclude that spontaneous bacterial peritonitis has a high risk of recurrence in hepatitis B-related cirrhosis and that the same disease occurring in patients with hepatocellular carcinoma is related to the underlying cirrhosis rather than the hepatocellular carcinoma.

Ascitic fluid analysis in peritoneal carcinomatosis: comparison of various biochemical tests with ascitic cirrhotics

Owing to the high false-negative rate of cytological examinations, various biochemical tests have been investigated to search for an alternative method to differentiate between the most frequent causes of ascites formation, i.e. cirrhosis of the liver and peritoneal carcinomatosis. For this purpose, serum and ascitic fluid samples of 71 ascitic patients (54 due to cirrhosis of the liver and 17 due to peritoneal carcinomatosis) were prospectively and simultaneously collected. Eleven major parameters were analyzed, and, of them, ascitic fluid protein, albumin, cholesterol, fibronectin and serum-ascitic gradient of protein and albumin were found to be useful. The serum-ascitic fluid albumin gradient was not as useful as described in the literature and, if clinically applied, the best cut-off value should be raised up to 1.5 gm/dl. Neither as useful was the serum-ascitic fluid protein gradient. Ascitic cholesterol and ascitic fibronectin were more accurate than the ascitic total protein, ascitic albumin and serum-ascitic gradient of protein and albumin in the diagnosis of peritoneal carcinomatosis. Of these tests, an ascitic fluid fibronectin concentration greater than 40 micrograms/ml was the most accurate parameter (diagnostic accuracy 96.2%) that could solely help to establish the diagnosis of peritoneal carcinomatosis.

Peripheral power errors and astigmatism of eyes corrected with intraocular lenses

We compared the theoretical peripheral power errors and oblique astigmatism of eyes corrected with commercially available intraocular lenses (IOL's) with experimental data of normal phakic eyes. The peripheral power errors and the oblique astigmatism of the pseudophakic eye are larger than those of phakic eyes. The most sensitive component of the optical system of the pseudophakic eye to the peripheral power errors is the shape of the IOL, but only if the lens is away from the iris. The corneal and the retinal surfaces do not affect the peripheral power errors and oblique astigmatism significantly. A plano-convex lens with the flat surface facing the cornea gives the least peripheral power errors and oblique astigmatism and thus the value closest to the experimental data of phakic eyes. However, this design does not give the minimum spherical aberration. Therefore, eyes corrected with IOL's are expected to have poorer peripheral retinal image quality than normal phakic eyes.

The aspherizing of intra-ocular lenses

While a spherically surfaced intra-ocular lens cannot be designed to give zero spherical aberration for the whole eye, aspherizing one surface of an intra-ocular lens can produce zero Seidel spherical aberration in a pseudophakic eye or set it to any desired level provided the corneal asphericity is known and this does not change with the operation. Equations for determining the asphericities are given. Asphericities for five lens shapes; the minimum spherical aberration lens and its reverse form, the equi-biconvex lens, the plano-convex lens and its reverse form are determined. The Seidel aberrations of eyes with aspherized intra-ocular lenses were compared with that of eyes with spherical intra-ocular lenses. While aspherizing eliminates the Seidel spherical aberration, some residual higher order spherical aberration exists and the amount of this residual spherical aberration depends upon the lens shape. However, this residual aberration can be reduced but not made zero by modifying the asphericity. For currently used plano-convex lenses, only the curves surface can be aspherized. The effect of variations in the anterior corneal asphericity on the necessary lens asphericity was also investigated.