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Supplementary Tables: Supplementary Table S1. Sequence of Chemically Synthesized Aptamers and RNA Supplementary Table S2. Sequences of primers for qRT-PCR and 5'RACE. Supplementary Figures: Supplementary Figure S1. 5'RACE analysis of Aptamer siRNA chimera directed cleavage of DNA-PK. Supplementary Figure S2. Stability of A10-3-DNAPK in human and mouse serum. Supplementary Figure S3. Systemic DNA-PK silencing by Aptamer-siRNA chimera.

Table S1: Weight of the tumors;Figure S1: Correlation of in vivo NIR imaging and ex vivo biodistribution analysis; Figure S2: Evaluation of injected J591-conjugates; Figure S3: Assessment of tumor vascular permeability; Figure S4: Passive dye uptake in PSMA-positive and PSMA-negative tumors; Figure S5: Ex vivo tumor image analysis of LMD/PSMA xenograft model; Figure S6: Ex vivo biodistribution analysis of J591-conjugates in LMD tumor model; Figure S7: Ex vivo tumor image analysis of PC3/PSMA xenograft model; Figure S8: PSMA expression and J591 conjugate distribution

Supplementary Figures S1-S2. S1. Schematic of the LimiNIR{trade mark, serif} System S2. PSMA expression in mouse epididymis and RT-PCR to validate the presence of PSMA mRNA

Supplementary Materials, Methods & Table S1. Supplementary Materials & Methods: Generation & characterization of the LMD-PSMA cells, YC-27 synthesis, primers for mPSMA PCR, and determining the limit of detection of YC-27. Supplementary Table S1: Residual tumor post surgery as determined by imaging and palpation. Author contributions & Competing interests.

Supplementary Movie S1. To model human laparoscopic tumor resection, athymic Nu/Nu mice harboring PSMA-positive xenografts were administered 19.1 μg/kg (HED of 100 μg for a 70 Kg male) YC-27 via tail vein injection. The mice were placed in a laparoscopic training box, and the PSMA-positive xenografts were resected 10 hours after injection of YC-27 with the guidance of the LumiNIR{trade mark, serif} system. Imaging was done using a 830nm laser to visualize the whole animal and 780nm laser to identify the PSMA-positive xenograft.

Purpose: The prostate-specific membrane antigen (PSMA) is a surface glycoprotein overexpressed on malignant prostate cells, as well as in the neovasculature of many tumors. Recent efforts to target PSMA for imaging prostate cancer rely on suitably functionalized low-molecular-weight agents. YC-27 is a low-molecular-weight, urea-based agent that enables near-infrared (NIR) imaging of PSMA in vivo.Experimental Design: We have developed and validated a laparoscopic imaging system (including an optimized light source, LumiNIR) that is capable of imaging small tumor burdens with minimal background fluorescence in real-time laparoscopic extirpative surgery of small prostate tumor xenografts in murine and porcine models.Results: In a mouse model, we demonstrate the feasibility of using real-time NIR laparoscopic imaging to detect and surgically remove PSMA-positive xenografts. We then validate the use of our laparoscopic real-time NIR imaging system in a large animal model. Our novel light source, which is optimized for YC-27, is capable of detecting as little as 12.4 pg/mL of the compound (2.48-pg YC-27 in 200-μL agarose). Finally, in a mouse xenograft model, we demonstrate that the use of real-time NIR imaging can reduce positive surgical margins (PSM).Conclusions: These data indicate that a NIR-emitting fluorophore targeted to PSMA may allow improved surgical treatment of human prostate cancer, reduce the rate of PSMs, and alleviate the need for adjuvant radiotherapy postoperatively. Clin Cancer Res; 21(4); 771–80. ©2014 AACR.

Background: We describe the first studies investigating a role for opiorphin genes ( PROL1, SMR3A and SMR3B) in prostate cancer (PrCa). Materials & methods: Databases and PrCa tissue arrays were screened for opiorphin expression. Xenografted tumor growth of human PrCa cells overexpressing PROL1 was compared with controls in nude mice. Modulated gene expression by overexpression of PROL1 was determined by RNA sequencing. Results: PrCa is associated with overexpression of opiorphin genes. Xenografted androgen-sensitive PrCa cells overexpressing PROL1 developed into tumors in castrated male mice (in contrast to parental cells). PROL1 overexpression modulates expression of genes in angiogenesis, steroid and hypoxic response pathways. Conclusions: Opiorphins promote the development of androgen-insensitive PrCa and activate pathways that potentially overcome the hypoxic barrier generated during tumor growth.

Landscape features, that affect the route of the line are the most significant part of this research. These features are incorporated into raster-based GIS, and using information gathered from stakeholders, the route with minimum opposition is developed between two substations. Routing with acceptable measured parameters of a line is also affected by the rules and regulations in a particular state. In this work, a brief introduction is given to the main legal requirements involved in this regard. Non-point impacts that are independent of terrain are also given in detail. Potential stakeholders, and their importance are also explained in this work. To carry out the proposed work, we will measure the radio frequency by not using the instrument used to measure the inaudible noise in the conventional way. With this, we will not acquire cost separately and the available resources will also be used, because different types of RF instruments are better than microphones for measuring radio frequency.

Background The opiorphin family of genes (represented in humans by ProL1, hSMR3A and hSMR3B) encode peptides which act as potent neutral endopeptidase (NEP) inhibitors. Because modulated NEP activity is associated with cancer development it has been suggested that dysregulated opiorphin expression may be involved in oncogenesis and recent reports have associated upregulated opiorphin gene expression with breast and oropharyngeal cancer. These observations prompted the present studies to determine if opiorphin genes play a role in prostate cancer (PrCa).Methods Publicly available data bases were screened for evidence associating opiorphin gene expression with PrCa and the findings confirmed using PrCa tissue arrays. Androgen-insensitive (PC3) and -sensitive (LNCaP) PrCa cells were engineered to overexpress ProL1, referred to as LNCaP-ProL1+ and PC3-ProL1+, respectively. Xenografted tumor growth of ProL1-overexpressing and parental cell-lines were compared in male, castrated-male and female nude mice. Changes in global gene expression resulting from overexpression of ProL1 in these cell-lines was determined by RNA-Seq.Results Publicly available datasets supported an association between overexpression of opiorphin genes and PrCa, which was confirmed using tissue arrays. Xenografted tumors derived from PC3-ProL1+ had an initial growth advantage over parent cell-lines in male mice, although at later time points there was no difference. Xenografted tumors derived from LNCaP-ProL1+ were able to grow in castrated male mice (in contrast to the parent cell-lines), and had impaired growth in female mice. Global gene expression analysis demonstrated that overexpression of ProL1 causes modulated expression of genes involved in signaling, angiogenesis and steroid response pathways.Conclusions This is the first report associating upregulated opiorphin gene expression and PrCa. Xengrafted tumors derived from the androgen-sensitive LNCaP cell-line engineered to overexpress ProL1 exhibit a more androgen-insensitive phenotype. Previous reports demonstrate opiorphins act as master regulators of the hypoxic response in smooth muscle cells. RNAseq data not only supports a similar role for ProL1 in PrCa (regulating genes involved in angiogenesis), but in addition, regulating genes involved in steroid response. Therefore, opiorphins may play a role in PrCa development by activating pathways that overcome the hypoxic environment of the developing tumor and promote the development of androgen-insensitivity.

Background and objective: A growing body of literature suggests modulated expression of members of the opiorphin family of genes (PROL1, SMR3A and SMR3B) is associated with cancer. Recently, overexpression of PROL1 was shown to be associated with prostate cancer, with evidence of a role in overcoming the hypoxic barrier that develops as tumors grow. The primary goal of the present studies was to support and expand evidence for a role of PROL1 in the development and progression of prostate cancer.Material and methods: We engineered knock-out of the opiorphin gene, PROL1, in LNCaP, an androgen-sensitive, human prostate cancer derived, cell-line. Using xenograft assays, we compared the ability of injected LNCaP PROL1 knock-out cell-lines to develop tumors in both castrated and intact male mice with the parental LNCaP and LNCaP PROL1 overexpressing cell-lines. We used RNAseq to compare global gene expression between the parental and LNCaP PROL1 knock-out cell-lines. Wound closure and 3D spheroid invasion assays were used to compare cell motility and migration between parental LNCaP cells and LNCaP cells overexpressing of PROL1.Results: The present studies demonstrate that LNCaP cell-lines with consisitutive knock-out of PROL1 fail to develop tumors when injected into both castrated and intact male mice. Using RNAseq to compare global gene expression between the parental and LNCaP PROL1 knock-out cell-lines, we confirmed a role for PROL1 in regulating molecular pathways associated with angiogenesis and tumor blood supply, and also identified a potential role in pathways related to cell motility and migration. Through the use of wound closure and 3D spheroid invasion assays, we confirmed that overexpression of PROL1 in LNCaP cells leads to greater cell motility and migration compared to parental cells, suggesting that PROL1 overexpression results in a more invasive phenotype.Conclusion: Overall, our studies add to the growing body of evidence that opiorphin-encoding genes play a role in cancer development and progression. PROL1 is essential for establishment and growth of tumors in mice injected with LNCaP cells, and we provide evidence that PROL1 has a possible role in progression towards a more invasive, metastatic and castration resistant prostate cancer (PrCa).

PURPOSE: Based on prior reports demonstrating that neutral endopeptidase (NEP) inhibitors increase sperm motility, the goal of our studies was to identify endogenous seminal peptides that inhibit NEP and investigate their potential effect on sperm motility. METHODS: Peptidomic analysis was performed on human seminal fluid, identifying 22 novel peptides. One peptide, named RSIY-11, derived from semenogelin-1, was predicted through sequence analysis to be a substrate and/or potential inhibitor of NEP. Enzymatic analysis was conducted to determine the inhibitory constant (Ki) of RSIY-11 as an inhibitor of NEP. Total and progressive sperm motility was determined at baseline and 30 and 60 min following addition of RSIY-11 to seminal fluid in 59 patients undergoing an infertility workup at an urban medical center. Additionally, the effects of RSIY-11 on sperm motility were evaluated in 15 of the 59 patients that met criteria for asthenospermia. RESULTS: RSIY-11 was shown to act as a competitive inhibitor of NEP with a Ki of 18.4 ± 1.6 μM. Addition of RSIY-11 at concentrations of 0.75 μM, 7.5 μM, and 75 μM significantly increased sperm motility at all time points investigated, with increases of 6.1%, 6.9%, and 9.2% at 60 min, respectively. Additionally, within the subgroup of patients with asthenospermia, RSIY-11 at concentrations of 0.75 μM, 7.5 μM, and 75 μM significantly increased sperm motility at all time points investigated, with increases of 7.6%, 8.8%, and 10.6% at 60 min, respectively. CONCLUSIONS: RSIY-11 is a newly identified semenogelin-1-derived peptide present in seminal fluid. RSIY-11 acts as a potent competitive inhibitor of NEP, which when added to seminal fluid significantly increases sperm motility. RSIY-11 could play a potential role in the treatment for male factor infertility related to asthenospermia and improve intrauterine insemination outcomes. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s10815-019-01524-8) contains supplementary material, which is available to authorized users.

Radiation therapy is a highly effective tool for treating all stages of prostate cancer, from curative approaches in localized disease to palliative care and enhanced survival for patients with distant bone metastases. The therapeutic index of these approaches may be enhanced with targeted radiation-sensitizing agents. Aptamers are promising nucleic acid delivery agents for short interfering RNAs (siRNA) and short hairpin RNAs (shRNA). We have previously developed a radiation-sensitizing RNA aptamer–shRNA chimera that selectively delivers DNA-PK targeting shRNAs to prostate-specific membrane antigen (PSMA) positive cells in the absence of transfection reagents. Although these chimera are effective, their synthesis requires in vitro transcription and their evaluation was limited to intratumoral administration. Here, we have developed a second-generation aptamer–siRNA chimera that can be assembled through the annealing of three separate chemically synthesized components. The resulting chimera knocked down DNA-PK in PSMA-positive prostate cancer cells, without the need of additional transfection reagents, and enhanced the efficacy of radiation-mediated cell death. Following intravenous injection, the chimera effectively knocked down DNA-PK in established subcutaneous PSMA-positive tumors. Systemic treatment with these radiation-sensitizing agents selectively enhanced the potency of external beam radiation therapy for established PSMA-positive tumors. Mol Cancer Ther; 14(12); 2797–804. ©2015 AACR.

Aim: To develop and apply a heat-responsive and secreted reporter assay for comparing cellular response to nanoparticle (NP)- and macroscopic-mediated sublethal hyperthermia. Materials & methods: Reporter cells were heated by water bath (macroscopic heating) or iron oxide NPs activated by alternating magnetic fields (nanoscopic heating). Cellular responses to these thermal stresses were measured in the conditioned media by secreted luciferase assay. Results & conclusion: Reporter activity was responsive to macroscopic and nanoparticle heating and activity correlated with measured macroscopic thermal dose. Significant cellular responses were observed with NP heating under doses that were insufficient to measurably change the temperature of the system. Under these conditions, the reporter response correlated with proximity to cells loaded with heated nanoparticles. These results suggest that NP and macroscopic hyperthermia may be distinctive under conditions of mild hyperthermia. Original submitted 10 May 2013; Revised submitted 31 October 2013

Genetic reporters provide a noninvasive method to monitor and evaluate a population of cells. The ideal properties of a gene reporter-probe system include biocompatibility, lack of immunogenicity, low background expression or signal, and high sensitivity of detection. The prostate-specific membrane antigen (PSMA) is an attractive candidate for a genetic reporter as it is a human transmembrane protein with a selective expression pattern, and there are several PSMA imaging agents available for clinical and preclinical applications. We evaluated the use of PSMA as a genetic imaging reporter by comparison to 2 clinically established reporters, the mutant herpes simplex virus type I thymidine kinase and the human sodium-iodide symporter. Methods: Adenoviruses expressing each reporter were constructed and validated in vitro for expression and function. To compare PSMA with existing imaging reporters, a bilateral Matrigel suspension model was established with nude mice bearing cells equally infected with each reporter or control adenovirus. Dynamic PET was performed, and time–activity curves were generated for each reporter-probe pair. Results: A comparison of peak target-to-background ratios revealed that PSMA offered the highest ratio relative to the control Matrigel suspension as well as muscle. Further, as proof of concept, PSMA was applied as an imaging reporter to monitor adenoviral liver transduction with both nuclear and optical imaging probes. Conclusion: These preliminary studies support further development of PSMA as a noninvasive genetic reporter.

In the present study, we carried out for the first time the antioxidant and antiinflammmatory activities of the different solvent extracts of the plant Ipomoea pes-caprae (L) sweet grown up in the marine enviornment of the Sunderban Mangrove eco-complex. It was observed that chloroform and ethyl acetate solvent extracts obtained from the methanolic extract of the plant had significant antioxidant and antiinflammatory activities. To trace the molecules responsible for these bioactivities, the chemical investigation of the plant yielded four pure compounds, 7-hydroxy-6-methoxycoumarin; 5,7,4'-trimethoxykaempferol; 3,7,8,3'4'-pentahydroxy flavone; trans-[3-(4'-hydroxyphenyl)-2-propenoic acid] which were identified by spectral methods. These compounds when tested individually, showed appreciable radical scavenging activities.

Macromolecular reagents can be targeted to tumors through active and passive mechanisms. “Active” targeting involves moieties, such as receptor ligands, to direct tumor cell binding, whereas “passive” targeting relies on long reagent circulating half-life, abnormal tumor vasculature, and poor lymphatic drainage for tumor entrapment. Here, we sought to study the impact of reagent circulating half-life on “active” and “passive” tumor uptake. The humanized prostate-specific membrane antigen (PSMA)-targeting antibody HuJ591 was used as the “active” targeting agent. HuJ591 was labeled with a Near Infrared (NIR) dye and its circulating half-life was modified by conjugation to high-molecular-weight Polyethylene Glycol (PEG). PEGylation did not negatively impact PSMA-binding specificity. “Active” and “passive” tumor targeting of intravenously injected antibody conjugates were then quantified by NIR fluorescent imaging of immunocompromised mice bearing bilateral isogenic PSMA-positive and PSMA-negative human tumor xenografts. Two isogenic tumor pairs were applied, PC3 ± PSMA (PC3-PIP/PC3-Flu) or LMD-MDA-MB-231 ± PSMA (LMD-PSMA/LMD). This study provided a unique model system to simultaneously observe “active” and “passive” tumor targeting within a single animal. “Passive” targeting was observed in all PSMA-negative tumors, and was not enhanced by increased HuJ591 size or extended circulating half-life. Interestingly, “active” targeting was only successful in some situations. Both PSMA-positive tumor models could be actively targeted with J591-IR800 and J591-PEG10K. However, the larger J591-PEG30K enhanced “active” targeting in the PC-3 tumor models, but inhibited “active” targeting the LMD-MDA-MB-231 tumor model. Successful “active” targeting was associated with higher PSMA expression. These results support the potential for “active” targeting to enhance overall macromolecular reagent uptake within tumors. Mol Cancer Ther; 15(10); 2541–50. ©2016 AACR.

Aptamers are a special class of nucleic acid molecules that are beginning to be investigated for clinical use. These small RNA/DNA molecules can form secondary and tertiary structures capable of specifically binding proteins or other cellular targets; they are essentially a chemical equivalent of antibodies. Aptamers have the advantage of being highly specific, relatively small in size, and non-immunogenic. Since the discovery of aptamers in the early 1990s, great efforts have been made to make them clinically relevant for diseases like cancer, HIV, and macular degeneration. In the last two decades, many aptamers have been clinically developed as inhibitors for targets such as vascular endothelial growth factor (VEGF) and thrombin. The first aptamer based therapeutic was FDA approved in 2004 for the treatment of age-related macular degeneration and several other aptamers are currently being evaluated in clinical trials. With advances in targeted-therapy, imaging, and nanotechnology, aptamers are readily considered as potential targeting ligands because of their chemical synthesis and ease of modification for conjugation. Preclinical studies using aptamer-siRNA chimeras and aptamer targeted nanoparticle therapeutics have been very successful in mouse models of cancer and HIV. In summary aptamers are in several stages of development, from pre-clinical studies to clinical trials and even as FDA approved therapeutics. In this review, we will discuss the current state of aptamers in clinical trials as well as some promising aptamers in pre-clinical development.

Glucocorticoid receptors (GRs) are ubiquitous, nuclear hormone receptors residing in cell types of both cancer and noncancerous origin. It is not known whether cancer cell-associated GR alone can be selectively manipulated for delivery of exogenous genes to its nucleus for eliciting anticancer effect. We find that GR ligand, dexamethasone (Dex) in association with cationic lipoplex (termed as targeted lipoplex) could selectively manipulate GR in cancer cells alone for the delivery of transgenes in the nucleus, a phenomenon that remained unobserved in normal cells. The targeted lipoplex (i) showed GR-targeted transfections in all cancer cells experimented (P0.01), (ii) significantly diminished transfection in cancer cells when GR is downregulated (P0.01), and (iii) elicited specific nuclear translocation of targeted lipoplex in cancer cells, followed by upregulated transactivation of glucocorticoid response element (GRE)- promoted gene. Using anticancer gene, targeted lipoplex induced significant tumor growth retardation in mice in comparison to different control groups (P0.05). Interestingly, cell surface-associated Hsp90 in cancer cells assisted the intracellular uptake of GR-targeted lipoplex. Moreover, selective inhibition of Hsp90 in noncancer cells resulted in cancer cell-like, aberrant, GR activation. The current study discovers a therapeutically important, unique property of cancer cell associated-GR that may be linked to a compromised role of Hsp90.Molecular Therapy (2009) 17 4, 623-631 doi:10.1038/mt.2009.4.

Sigma receptors are membrane-bound proteins that are overexpressed in certain human malignancies including breast cancer. These receptors show very high affinity for various sigma ligands including neuroleptics like haloperidol. We hypothesized that in associating haloperidol-linked lipid into the cationic lipid-DNA complex, we can specifically target and deliver genes to breast cancer cells that overexpress sigma receptors. In the present study, haloperidol was chemically modified to conjugate at the distal end of the polyethylene glycollinked phospholipid, which was then incorporated into the cationic liposome known to condense and deliver genes inside cells. The resulting haloperidol-conjugated targeted lipoplex showed at least 10-fold higher (p

Purpose: The prostate-specific membrane antigen (PSMA) is a surface glycoprotein overexpressed on malignant prostate cells, as well as in the neovasculature of many tumors. Recent efforts to target PSMA for imaging prostate cancer rely on suitably functionalized low-molecular-weight agents. YC-27 is a low-molecular-weight, urea-based agent that enables near-infrared (NIR) imaging of PSMA in vivo. Experimental Design: We have developed and validated a laparoscopic imaging system (including an optimized light source, LumiNIR) that is capable of imaging small tumor burdens with minimal background fluorescence in real-time laparoscopic extirpative surgery of small prostate tumor xenografts in murine and porcine models. Results: In a mouse model, we demonstrate the feasibility of using real-time NIR laparoscopic imaging to detect and surgically remove PSMA-positive xenografts. We then validate the use of our laparoscopic real-time NIR imaging system in a large animal model. Our novel light source, which is optimized for YC-27, is capable of detecting as little as 12.4 pg/mL of the compound (2.48-pg YC-27 in 200-μL agarose). Finally, in a mouse xenograft model, we demonstrate that the use of real-time NIR imaging can reduce positive surgical margins (PSM). Conclusions: These data indicate that a NIR-emitting fluorophore targeted to PSMA may allow improved surgical treatment of human prostate cancer, reduce the rate of PSMs, and alleviate the need for adjuvant radiotherapy postoperatively. Clin Cancer Res; 21(4); 771–80. ©2014 AACR.

Network support for variable bit-rate video needs to consider (i) properties of workload induced (e.g., significant auto-correlations into far lags and heterogeneous marginal distributions), and (ii) application specific bounds on delay-jitter and statistical cell-loss probabilities. The objective of this paper is to present a quality-of-service solution for such traffic at each multiplexing point in a network. Heterogeneity in both offered workload and quality-of-service requirements are addressed. A per-virtual-circuit framing structure and a pseudo earliest-due-date cell dispatcher are introduced to provide guaranteed delay-jitter bounds. Heterogeneous jitter-bounds are supported through software controlled frame-sizes which may be independently set for each virtual-circuit. The framing structure is a generalization of per-link framing introduced by Golestani. The proposed framing structure eliminates correcting for phase mismatches between incoming frames and outgoing frames, necessary in per-link framing. This results in reduction in end-to-end delay bound and buffer requirements, and a simpler implementation. Strong auto-correlations typically seen in video traffic make equivalent bandwidth computations for heterogeneous cell-loss bounds intractable. To address this, the framing strategy is combined with an active cell-discard mechanism with prioritized cell-dropping, the latter utilizing the history of dropped cells and target cell-loss bounds for each virtual circuit. Upper bounds on the equivalent bandwidth needed to support a given workload with a target quality of service are developed. These are validated through numerical and simulation results from variable bit-rate MPEG-I video traces.

The prostate-specific membrane antigen (PSMA) is an established target for the delivery of cancer therapeutic and imaging agents due to its high expression on the surface of prostate cancer cells and within the neovasculature of other solid tumors. Here, we describe the synthesis and screening of antibody-conjugated silica-coated iron oxide nanoparticles for PSMA-specific cell targeting. The humanized anti-PSMA antibody, HuJ591, was conjugated to a series of nanoparticles with varying densities of polyethylene glycol and primary amine groups. Customized assays utilizing iron spectral absorbance and enzyme-linked immunoassay (ELISA) were developed to screen microgram quantities of nanoparticle formulations for immunoreactivity and cell targeting ability. Antibody and PSMA-specific targeting of the optimized nanoparticle was evaluated using an isogenic PSMA-positive and PSMA-negative cell line pair. Specific nanoparticle targeting was confirmed by iron quantification with inductively coupled plasma mass spectrometry (ICP-MS). These methods and nanoparticles support the promise of targeted theranostic agents for future treatment of prostate and other cancers.

We explore design principles for next-generation optical wide-area networks, employing wavelength-division multiplexing (WDM) and targeted to nationwide coverage. This optical network exploits wavelength multiplexers and optical switches in routing nodes, so that an arbitrary virtual topology may be embedded on a given physical fiber network. The virtual topology, which is used as a packet-switched network and which consists of a set of all-optical "lightpaths", is set up to exploit the relative strengths of both optics and electronics-viz. packets of information are carried by the virtual topology "as far as possible" in the optical domain, but packet forwarding from lightpath to lightpath is performed via electronic switching, whenever required. We formulate the virtual topology design problem as an optimization problem with one of two possible objective functions: (1) for a given traffic matrix, minimize the network-wide average packet delay (corresponding to a solution for present traffic demands), or (2) maximize the scale factor by which the traffic matrix can be scaled up (to provide the maximum capacity upgrade for future traffic demands). Since simpler versions of this problem have been shown to be NP-hard, we resort to heuristic approaches. Specifically, we employ an iterative approach which combines "simulated annealing" (to search for a good virtual topology) and "flow deviation" (to optimally route the traffic-and possibly bifurcate its components-on the virtual topology). We do not consider the number of available wavelengths to be a constraint, i.e., we ignore the routing of lightpaths and wavelength assignment for these lightpaths. We illustrate our approaches by employing experimental traffic statistics collected from NSFNET.

We present a feedback congestion control method, Dynamic Time Windows, for use in high speed wide area networks based on controlling source variance. It is part of the two-level integrated congestion control system introduced in our earlier work[1]. The method consists of a packet admission control system and a feedback system to dynamically control source burstiness. Source throughput is not modulated as with traditional packet windows, allowing system throughput to remain high while avoiding congestion. Furthermore, the admission control bounds congestion times in the network, allowing feedback to be effective in the face of large bandwidth delay products. The basic control mechanisms are analogs to traditional packet windows applied to controlling time windows - a new mechanism which allows switches to modulate source variances. The proposed system is simulated, and the results reported and analyzed. Enhancements to the basic system are also proposed and analyzed. We wish to stress that the system described here is the second level of a two-level congestion control. Previous work[1] concentrated on the switch queueing mechanism, Pulse, while this work is a detailed examination of the feedback system used to adjust time windows to changing network load.

Sigma receptors are membrane-bound proteins that are overexpressed in certain human malignancies including breast cancer. These receptors show very high affinity for various sigma ligands including neuroleptics like haloperidol. We hypothesized that in associating haloperidol-linked lipid into the cationic lipid-DNA complex, we can specifically target and deliver genes to breast cancer cells that overexpress sigma receptors. In the present study, haloperidol was chemically modified to conjugate at the distal end of the polyethylene glycollinked phospholipid, which was then incorporated into the cationic liposome known to condense and deliver genes inside cells. The resulting haloperidol-conjugated targeted lipoplex showed at least 10-fold higher (p0.001) reporter gene expression in MCF-7 cells than control lipoplex. The reporter gene expression of the targeted lipoplex was significantly blocked by haloperidol (p0.001) and by another sigma ligand, 1,3-ditolylguanidine (p0.001) in the majority of cationic lipid to DNA charge ratios (+/-). Spironolactone-mediated sigma receptor down-regulation enabled MCF-7 to show 10-fold lower transgene expression with targeted lipoplex compared with that obtained in spironolactone-untreated cells. The targeted lipoplex generated nonspecific gene expression in sigma receptor-nonexpressing human cancer cells such as Hela, KB, HepG2, and Chinese hamster ovary cells. Moreover, the transgene expression remained unabated in physiologically relevant serum concentrations. This is the first study to demonstrate that haloperidol-targeted gene delivery systems can mediate efficient targeting of genes to sigma receptor-overexpressing breast cancer cells, thereby becoming a novel class of therapeutics for the treatment of human cancers.

Network support for variable bit-rate video needs to consider (1) properties of workload induced (e.g., significant autocorrelations into far lags and heterogeneous marginal distributions), and (2) application specific bounds on delay-jitter and statistical cell-loss probabilities. The objective of this paper is to present a quality-of-service solution for such traffic at each multiplexing point in a network. Heterogeneity in both offered workload and quality- of-service requirements are addressed. A per-virtual-circuit framing structure and a pseudo earliest-due-date cell dispatcher are introduced to provide guaranteed delay-jitter bounds. Heterogeneous jitter-bounds are supported through software controlled frame-sizes which may be independently set for each virtual-circuit. The framing structure is a generalization of per-link framing introduced by Golestani. The proposed framing structure eliminates correcting for phase mismatches between incoming frames and outgoing frames, necessary in per-link framing. This results in reduction in end-to-end delay bound, buffer requirements, and a simpler implementation. Strong auto-correlations typically seen in video traffic make equivalent bandwidth computations for heterogeneous cell-loss bounds intractable. To address this, the framing strategy is combined with an active cell-discard mechanism with prioritized cell- dropping, the latter utilizing the history of dropped cells and target cell-loss bounds for each virtual circuit. Upper bounds on the equivalent bandwidth needed to support a given workload with a target quality of service are also given. These are validated through numerical and simulation results from variable bit-rate MPEG-I video traces.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Data traffic sequences from two campus FDDI rings, an Ethernet, two entry/exit points of the NSFNET, and sub-sequences belonging to popular TCP port numbers on one of the FDDI rings indicate that appropriately differenced time-series generated from these traces can be modeled as auto-regressive moving average (ARMA) processes. The variates of the ARMA filter are, however, non-Gaussian. A sequence of steps leading through (i) parameter estimation, (ii) generating the distribution of the variates, (iii) forecasting tail percentiles, and (iv) synthetic generation of non-negative integer sequences is presented. The data indicates that parameter estimates drift slowly with time and may need to be re-computed periodically for accurate forecasts. The forecasting algorithm, has potential application in dynamic resource allocation. The synthetic traffic generation algorithm may be used in simulation studies of resource management algorithms.

The authors present mechanisms for congestion control of data traffic in high-speed wide area networks. The network model assumes reservation of resources based on average requirements. The key ideas involve separation of different sources of network congestion, short-term bursts and medium-term load, and using separate mechanisms to address them. Thus, dynamic time window (DTW) admission control is proposed as a mechanism to limit traffic burstiness from sources as a function of the medium-term load on the system, while a new fairness criterion for short-term congestion (Pulse) is proposed as a mechanism for dealing with fair scheduling by switches of short-term bursts. The model of the network is presented. The DTW and Pulse mechanisms are discussed. A detailed analytical and simulation study is presented for static time-windows and various scheduling algorithms. Preliminary results on DTW are discussed. >

We present an evaluation of retransmission strategies over local area networks. Expressions are derived for the expectation and the variance of the transmission time of the go-back-n and the selective repeat protocols in the presence of errors. These are compared to the expressions for blast with full retransmission on error (BFRE) derived by Zwaenepoel [Zwa 85]. We conclude that go-back-n performs almost as well as selective repeat and is very much simpler to implement while BFRE is stable only for a limited range of messages sizes and error rates. We also present a variant of BFRE which optimally checkpoints the transmission of a large message. This is shown to overcome the instability of ordinary BFRE. It has a simple state machine and seems to take full advantage of the low error rates of local area networks. We further investigate go-back-n by generalizing the analysis to an upper layer transport protocol, which is likely to encounter among other things, variable delays due to protocol overhead, multiple connections, process switches and operating system scheduling priorities.