A prospective comparative study of the AMO ARRAY zonal-progressive multifocal silicone intraocular lens and a monofocal intraocular lens.

OBJECTIVE: To evaluate the safety and effectiveness of a zonal-progressive multifocal silicone intraocular lens (IOL). DESIGN: Prospective, nonrandomized, fellow eye comparative trial. PARTICIPANTS: Four hundred fifty-six subjects were enrolled at 14 investigational sites in the United States; 400 subjects achieved 1-year follow-up. A subset of 123 subjects (102 at 1 year) were enrolled in a monofocal fellow eye control substudy; subjects were implanted with the multifocal IOL in one eye and a comparable monofocal IOL in the fellow eye. METHODS: Cataract extraction and implantation of a zonal-progressive multifocal silicone IOL was performed using the surgeon's standard technique. Subjects were followed at six postoperative examination intervals through 1 year. MAIN OUTCOME MEASURES: The key efficacy measures were mean uncorrected and corrected distance and near visual acuity at 1 year after surgery. RESULTS: In the monofocal fellow eye control substudy, the multifocal eyes showed a mean 2-line increase over monofocal eyes for uncorrected and distance-corrected near visual acuity (P < 0.0001). Mean uncorrected distance visual acuity was similar between multifocal and monofocal eyes (P = 0.116). A significantly higher proportion of bilateral multifocal subjects reported that they could function comfortably without glasses at near (81%, 96 of 118) compared with multifocal/monofocal subjects (56%; 93 of 165; P < 0.001) and unilateral multifocal subjects (58%; 56 of 97; P < 0.001). Low-contrast visual acuity was reduced in multifocal eyes by approximately 1 Snellen line. However, no perceived disadvantages attributable to the reduction in low-contrast acuity were found. Although the perception of halos and glare increased in the multifocal eyes, good visual function remained, and nearly all subjects were satisfied with the results of their surgery. CONCLUSIONS: In a large study that included a subset of subjects with paired eye compared with those with monofocal lenses, this zonal-progressive multifocal lens provided a high level of uncorrected and corrected distance vision, improved uncorrected and distance-corrected near vision, reduced spectacle dependency, and a high level of patient satisfaction despite some loss of low-contrast visual acuity and increased reports of halos and glare.

In vivo inhibition of NF-kappa B in T-lineage cells leads to a dramatic decrease in cell proliferation and cytokine production and to increased cell apoptosis in response to mitogenic stimuli, but not to abnormal thymopoiesis.

To understand the role of NF-kappa B complexes in T cell development and activation, we have generated transgenic mice in which RelA and c-Rel complexes were selectively inhibited in the T-lineage cells by specific expression of a trans-dominant form of I kappa B alpha. Transgene expression did not affect the thymic development, but led to lowered numbers of splenic T cells and to a dramatic decrease in the ex vivo proliferative response of splenic T lymphocytes. Analysis of IL-2 and IL-2R alpha expression demonstrated that the perturbation of the proliferation response was not attributable to an abnormal expression of these genes. In contrast, expression of IL-4, IL-10, and IFN-gamma was strongly inhibited in the transgenic T cells. The proliferative deficiency of the transgenic T cells was associated with an increased apoptosis. These results point out the involvement of NF-kappa B/Rel family proteins in growth signaling pathways by either regulating proteins involved in the IL-2 signaling or by functionally interfering with the cell cycle progression.

Relationship between IkappaBalpha constitutive expression, TNFalpha synthesis, and apoptosis in EBV-infected lymphoblastoid cells.

In order to understand the role of NF-kappaB in EBV transformation we have established stably transfected IkappaBalpha into lymphoblastoid cells. Two clones were obtained in which the loss of NF-kappaB binding activity correlated with the constitutive expression of the transgenic IkappaBalpha. Protein latency expression was determined by immunocytochemistry. Expression of surface markers, intracytoplasmic content of cytokines cell cycle analysis after BrdU incorporation and DNA staining with propidium iodide were studied by flow cytometry. Percentage of apoptotic cells was determined by in-situ labelling of DNA strand breaks. No significative changes in EBV latency nor in cell surface marker expression was found. In contrast, intracytoplasmic TNFalpha levels were strongly reduced in transfected clones. Furthermore, 30% of IkappaBalpha transfected cells were apoptotic after 8 h of TNFalpha treatment. This correlated with a strong reduction of BrdU incorporation after 24 h of TNFalpha treatment. No effect was seen with non transfected cells or with cells transfected with a control plasmid. Our results suggest that the TNFalpha gene could be one of the targets of NF-kappaB in EBV infected cells and that NF-kappaB protects EBV-infected cells from apoptosis induced by TNFalpha, which may favour the proliferative effect of this cytokine.

Discrimination between RelA and RelB transcriptional regulation by a dominant negative mutant of IkappaBalpha.

RelA and RelB belong to the nuclear factor-kappaB (NF-kappaB-Rel) transcription factor family. Both proteins are structurally and functionally related, but their intracellular and tissue distributions are different. In resting cells, RelB is found mostly in the nucleus, whereas RelA is sequestered in the cytosol by protein inhibitors, among which IkappaBalpha is the dominant form in lymphocytes. Upon cellular activation IkappaBalpha is proteolyzed, allowing RelA dimers to enter the nucleus and activate target genes. To study the selectivity of gene regulation by RelA and RelB, we generated T cell lines stably expressing a dominant negative mutant of IkappaBalpha. We show that selective inhibition of RelA-NF-kappaB decreased induction of NFKB1, interleukin-2, and interleukin-2Ralpha genes but not c-myc. Transcription driven by the IkappaBalpha promoter was blocked by the transgenic IkappaBalpha; however, wild type IkappaBalpha was expressed in the transgenic cell clones but with much slower kinetics than that in control cells. Wild type IkappaBalpha expression was concomitant with RelB up-regulation, suggesting that RelB could be involved in transcription of IkappaBalpha through binding to an alternative site. These results indicate that RelB and RelA have both distinct and overlapping effects on gene expression.

Outcomes of cataract extraction with multifocal intraocular lens implantation: functional status and quality of life.

OBJECTIVE: The authors measured functional status after bilateral implantation of a multifocal versus a monofocal intraocular lens (IOL). METHODS: A retrospective, case-control study was done on 100 subjects implanted bilaterally with a silicone-optic foldable zonal progressive IOL under United States Food and Drug Administration Investigational Device Exemption protocol and 103 control subjects implanted bilaterally with a monofocal IOL of similar design who were matched on age and postoperative corrected distance acuity. The Cataract TyPE specification, a 17-item functional status instrument, was modified, validated, and administered via telephone interview. The measures of vision, functional status, and quality of life were compared between patients and controls. RESULTS: The instrument was valid (Cronbach's alpha = 0.94) and correlated moderately (Pearson's r= 0.34) with Snellen acuity. Multifocal subjects were more likely than monofocal controls to never wear spectacles (41% vs. 11.7%; P < 0.001). Multifocal subjects rated their vision without spectacles significantly better than those with monofocal IOLs (9.0 vs. 7.9; P < 0.001). The difference was most significant in rating of near vision without spectacles (7.8 vs. 5.0; P < 0.001). Multifocal subjects reported less limitation in specific visual tasks without spectacles (0.3 vs. 0.8; P < 0.001, where 1.0 represents "slightly" limited). This difference was consistently observed in subscales related to distance vision activities (0.1 vs. 0.4; P < 0.001), near vision activities (0.6 vs. 1.4; P < 0.001), and social activities (0.1 vs. 0.6; P < 0.001). CONCLUSIONS: In this study, subjects with bilateral multifocal IOLs reported better overall vision, less limitation in visual function, and less spectacle usage than monofocal controls.

Nuclear Rel-A and c-Rel protein complexes are differentially distributed within human thymocytes.

Nuclear factor-kappa B (NF-kappa B)/Rel proteins are inducible transcriptional regulators of numerous cellular genes. They are particularly abundant in lymphoid tissues and are thought to be critical for the transcription of genes involved in immune and inflammatory responses. We have reported previously that a nuclear NF-kappa B activity was present in freshly extracted human thymocytes in the absence of in vitro treatment of these cells. In the present report, we identified NF-kappa B proteins extracted from human thymocyte nuclei as being p50/p65 and p50/c-Rel complexes. Immunochemical and immunofluorescent staining of thymus sections using specific Abs allowed visualization of nuclear NF-kappa B proteins in both thymocytes and nonthymocyte cells. This detection suggested a preferential activation of p50/c-Rel in medullary thymocytes, whereas p50/p65 was present in both cortical and medullary regions of human thymus lobules. However, the intensity of p65 labeling was much higher in several thymocytes from the medulla. p65, p50, and c-Rel activities were found in both CD4- and CD8-positive thymocytes. These observations suggest that p65 and c-Rel complexes play distinct roles in gene expression and that both forms of NF-kappa B play critical roles during late stages of the intrathymic maturation of T cells.

IkappaB alpha overexpression in human breast carcinoma MCF7 cells inhibits nuclear factor-kappaB activation but not tumor necrosis factor-alpha-induced apoptosis.

Nuclear factor-kappaB (NF-kappaB) is one of major component induced by tumor necrosis factor-alpha (TNF), and its role in the signaling of TNF-induced cell death remains controversial. In order to delineate whether the involvement of NF-kappaB activation is required for triggering of the apoptotic signal of TNF, we inhibited the nuclear translocation of this transcription factor in TNF-sensitive MCF7 cells by introducing a human MAD-3 mutant cDNA coding for a mutated IkappaB alpha that is resistant to both phosphorylation and proteolytic degradation and that behaves as a potent dominant negative IkappaB alpha protein. Our results demonstrated that the mutated IkappaB alpha was stably expressed in the transfected MCF7 cells and blocked the TNF-induced NF-kappaB nuclear translocation. Indeed, TNF treatment of these cells induced the proteolysis of only the endogenous IkappaB alpha but not the mutated IkappaB alpha. The nuclear NF-kappaB released from the endogenous IkappaB alpha within 30 min of TNF treatment was rapidly inhibited by the mutated IkappaB alpha. There was no significant difference either in cell viability or in the kinetics of cell death between control cells and the mutated IkappaB alpha transfected cells. Furthermore, electron microscopic analysis showed that the cell death induced by TNF in both control and mutated IkappaB alpha transfected cells was apoptotic. The inhibition of NF-kappaB translocation in mutated IkappaB alpha-transfected cells persisted throughout the same time course that apoptosis was occurring. Our data provide direct evidence that the inhibition of NF-kappaB did not alter TNF-induced apoptosis in MCF7 cells and support the view that TNF-mediated apoptosis is NF-kappaB independent.

Activation of nuclear factor kappa B in human neuroblastoma cell lines.

The nuclear factor kappa B (NF-kappa B) is a eukaryotic transcription factor. In B cells and macrophages it is constitutively present in cell nuclei, whereas in many other cell types, NF-kappa B translocates from cytosol to nucleus as a result of transduction by tumor necrosis factor alpha (TNF alpha), phorbol ester, and other polyclonal signals. Using neuroblastoma cell lines as models, we have shown that in neural cells NF-kappa B was present in the cytosol and translocated into nuclei as a result of TNF alpha treatment. The TNF alpha-activated NF-kappa B was transcriptionally functional. NF-kappa B activation by TNF alpha was not correlated with cell differentiation or proliferation. However, reagents such as nerve growth factor (NGF) and the phorbol ester phorbol 12-myristate 13-acetate (PMA), which induce phenotypical differentiation of the SH-SY5Y neuroblastoma cell line, activated NF-kappa B, but only in that particular cell line. In a NGF-responsive rat pheochromocytoma cell line, PC12, PMA activated NF-kappa B, whereas NGF did not. In other neuroblastoma cell lines, such as SK-N-Be(2), the lack of PMA induction of differentiation was correlated with the lack of NF-kappa B activation. We found, moreover, that in SK-N-Be(2) cells protein kinase C (PKC) enzymatic activity was much lower compared with that in a control cell line and that the low PKC enzymatic activity was due to low PKC protein expression. NF-kappa B was not activated by retinoic acid, which induced morphological differentiation of all the neuroblastoma cell lines used in the present study. Thus, NF-kappa B activation was not required for neuroblastoma cell differentiation. Furthermore, the results obtained with TNF alpha proved that NF-kappa B activation was not sufficient for induction of neuroblastoma differentiation.

Differential expression of PKC alpha and PKC beta isozymes in CD4+, CD8+ and CD4+/CD8+ double positive human T cells.

Using specific monoclonal and polyclonal antibodies, we have analyzed protein kinase C alpha and beta isozyme expression in human T cells from peripheral blood (PB) and from thymus. While the PKC beta isozyme was present in all T cell sub-types isolated from both PB and thymus, the alpha isozyme was found only in single positive CD4+ thymocytes, in PB-CD4+ lymphocytes and in PB-CD8+ T cells from several donors. It was absent from both, CD8+ and double positive CD4+/CD8+ thymocytes. These results show that PKC alpha and -beta are differentially regulated during intra-thymic development and suggest that PKC alpha plays a specific role in helper T cell function.

Constitutive activation of NF-kB in human thymocytes.

NF-kB is a eukaryotic transcription regulatory factor. In T cells and T cell lines, NF-kB is bound to a cytoplasmic proteic inhibitor, the IkB. Treatment of T cells with mitogens (phorbol esters) or cytokines (TNF alpha) induces NF-kB nuclear translocation and the subsequent expression of NF-kB dependent T cell genes. Here we examined the activation of NF-kB in human T cell thymic progenitors. We report differences in (Ca2+)i requirement for NF-kB activation in thymocytes as compared to mature T cells. Furthermore, our results indicated that thymocytes have a constitutively active form of NF-kB, suggesting that they are activated in vivo.

Stathmin phosphorylation patterns discriminate between distinct transduction pathways of human T lymphocyte activation through CD2 triggering.

CD2 triggering of human T lymphocyte activation has been associated with the activation of different interacting protein kinases, including protein kinase C (PKC). However the precise roles of its phosphorylated substrates are still unknown. We show here that PKC-dependent and -independent pathways are responsible for the CD2-induced phosphorylation of stathmin, a ubiquitous soluble phosphoprotein, most likely acting as a general intracellular relay integrating various second messenger pathways. The phosphorylated variants of stathmin provide a fingerprint reflecting the second messenger pathway(s) stimulated. The respective roles of both PKC and stathmin in the regulation of T lymphocyte proliferation are discussed.

CD2 triggering stimulates a phospholipase A2 activity beside the phospholipase C pathway in human T lymphocytes.

In previous studies we demonstrated the triggering of the phospholipase C (PLC) pathway during the activation of an Ag-specific human CD4+ T lymphocyte clone by a mitogenic pair of CD2 (X11,D66) mAb. Similar conditions were applied to investigate a possible involvement of a phospholipase A2 (PLA2) acting as an additional alternative pathway during human T cell activation. Our results show that arachidonic acid or its derivatives are released after CD2 triggering. This release is largely independent of PLC activation and is mediated by a PLA2 because: 1) phosphatidylcholine is the preferential source of [3H]arachidonate release; 2) [3H]arachidonic acid release and phosphatidylcholine hydrolysis are blocked by two inhibitors of solubilized PLA2, mepacrine, and 4-p-bromophenacylbromide; and 3) we evidenced a PLA2 activity in cell homogenates. Extracellular calcium appears to play a critical role because the effects of CD2 mAb were inhibited in a Ca2(+)-depleted medium. In contrast, protein kinase C is not implicated since PMA, a protein kinase C activator, neither stimulated arachidonic acid release nor modulated CD2-induced arachidonic acid release. Cyclic AMP which has been proved to regulate the activity of the PLC in T lymphocytes does not appear to play an important role in the regulation of PLA2 activity since PGE2 has only a minimal effect on [3H]-arachidonate release. Altogether, these findings suggest that CD2 triggering stimulates a PLA2 activity in T lymphocytes via an extracellular Ca2(+)-dependent PLC protein kinase C independent mechanism.