Identification and characterization of multiple osmotic response sequences in the human aldose reductase gene

Aldose reductase (AR) has been implicated in osmoregulation in the kidney because it reduces glucose to sorbitol, which can serve as an osmolite. Under hyperosmotic stress, transcription of this gene is induced to increase the enzyme level. This mode of osmotic regulation of AR gene expression has been observed in a number of nonrenal cells as well, suggesting that this is a common response to hyperosmotic stress. We have identified a 132-base pair sequence approximately 1 kilobase pairs upstream of the transcription start site of the AR gene that enhances the transcription activity of the AR promoter as well as that of the SV40 promoter when the cells are under hyperosmotic stress. Within this 132-base pair sequence, there are three sequences that resemble TonE, the tonicity response element of the canine betaine transporter gene, and the osmotic response element of the rabbit AR gene, suggesting that the mechanism of osmotic regulation of gene expression in these animals is similar. However, our data indicate that cooperative interaction among the three TonE-like sequences in the human AR may be necessary for their enhancer function.

Purification, identification, and characterization of an osmotic response element binding protein

Kidney cells, especially the epithelial cells lining the collecting tubules in the inner medulla, are constantly exposed to concentrated urine. They are protected from the osmotic effect of high levels of sodium ion and urea by accumulating compatible osmolytes such as sorbitol, betaine, and myo-inositol. These osmolytes are involved in maintaining cell volume and electrolyte contents because they do not perturb the protein structure and function over a wide range of concentrations. Sorbitol is produced via the reduction of glucose by aldose reductase (AR), while betaine and myo-inositol are transported into the cells through specific transporters. Under hyperosmotic stress, transcriptions of genes encoding these proteins are highly induced. The induction of transcription was found to be mediated through the osmotic response elements (OREs) located in the 5' flanking sequences of these genes. We had earlier identified the OREs in human AR gene. In this study we purified and identified the osmotic response element binding protein (OREBP). OREBP is a transcription factor of approximately 200 kDa in size, characterized by a Rel-like DNA binding domain and a glutamine-rich transactivation domain. Dominant negative OREBP significantly diminished hyperosmotic AR gene induction. Immunohistochemical analysis showed that this transcription factor is rapidly translocated into the nucleus upon hyperosmotic stress.

Aldose reductase-deficient mice develop nephrogenic diabetes insipidus

Aldose reductase (ALR2) is thought to be involved in the pathogenesis of various diseases associated with diabetes mellitus, such as cataract, retinopathy, neuropathy, and nephropathy. However, its physiological functions are not well understood. We developed mice deficient in this enzyme and found that they had no apparent developmental or reproductive abnormality except that they drank and urinated significantly more than their wild-type littermates. These ALR2-deficient mice exhibited a partially defective urine-concentrating ability, having a phenotype resembling that of nephrogenic diabetes insipidus.

An (A-C)n dinucleotide repeat polymorphic marker at the 5' end of the aldose reductase gene is associated with early-onset diabetic retinopathy in NIDDM patients

To study the relationship between the aldose reductase gene and diabetic complications, an (A-C)n dinucleotide repeat sequence 2.1 kb upstream of the transcription start site of this gene was identified and studied. There are seven alleles at this locus with a polymorphism information content of 0.73 and a heterozygosity of 0.77 among the Chinese population in Hong Kong. One of the alleles (Z-2) was found to be associated with early onset of retinopathy in patients with non-insulin-dependent diabetes (P = 0.007), suggesting that aldose reductase or a gene in the close vicinity may be involved in the pathogenesis of this diabetic complication.

NFAT5 in cellular adaptation to hypertonic stress - regulations and functional significance

The Nuclear Factor of Activated T Cells-5 (NFAT5), also known as OREBP or TonEBP, is a member of the nuclear factors of the activated T cells family of transcription factors. It is also the only known tonicity-regulated transcription factor in mammals. NFAT5 was initially known for its role in the hypertonic kidney inner medulla for orchestrating a genetic program to restore the cellular homeostasis. Emerging evidence, however, suggests that NFAT5 might play a more diverse functional role, including a pivotal role in blood pressure regulation and the development of autoimmune diseases. Despite the growing significance of NFAT5 in physiology and diseases, our understanding of how its activity is regulated remains very limited. Furthermore, how changes in tonicities are converted into functional outputs via NFAT5 remains elusive. Therefore, this review aims to summarize our current knowledge on the functional roles of NFAT5 in osmotic stress adaptation and the signaling pathways that regulate its activity.

Evidence for an interaction between ubiquitin-conjugating enzymes and the 26S proteasome

The targeting of proteolytic substrates is accomplished by a family of ubiquitin-conjugating (E2) enzymes and a diverse set of substrate recognition (E3) factors. The ligation of a multiubiquitin chain to a substrate can promote its degradation by the proteasome. However, the mechanism that facilitates the translocation of a substrate to the proteasome in vivo is poorly understood. We have discovered that E2 proteins, including Ubc1, Ubc2, Ubc4, and Ubc5, can interact with the 26S proteasome. Significantly, the interaction between Ubc4 and the proteasome is strongly induced by heat stress, consistent with the requirement for this E2 for efficient stress tolerance. A catalytically inactive derivative of Ubc4 (Ubc4(C86A)), which causes toxicity in yeast cells, can also bind the proteasome. Purified proteasomes can ligate ubiquitin to a test substrate without the addition of exogenous E2 protein, suggesting that the ubiquitylation of some proteolytic substrates might be directly coupled to degradation by the proteasome.

Overexpression of aldose reductase in liver cancers may contribute to drug resistance

We previously found that about 29% of human liver cancers overexpressed aldose reductase (AR) and about 54% of them overexpressed an AR-like gene called ARL-1 that has similar enzymatic activities to AR. Since these aldo-keto reductases can reduce a broad spectrum of substrates including cytotoxic aldehydes, we were interested to find out if these enzymes can contribute to the resistance of liver cancer chemotherapy by inactivating some of the anticancer drugs. HepG2 cells, a stable line of liver cells, were induced to overexpress AR by hypertonicity. Cells that were cultured in hypertonic medium became more resistant to daunorubicin, suggesting that overexpression of AR made the cells more resistant to this drug. This is confirmed by the fact that addition of AR inhibitor sensitizes the cells to this drug again. This information may be important for designing new drugs to treat this deadly disease.

Trachoma, flies and environmental factors in Burkina Faso

The presence of flies is one of the earliest risk factors for trachoma and it has been suggested that flies could act as vectors for transmission of chlamydiae. A national trachoma survey was conducted in 1997 in Burkina Faso to (i) study the relationship between trachoma occurrence, flies, dirty faces and some environmental factors, and (ii) investigate the role of flies in the presence of trachoma. The country was stratified into eight groups of provinces and a random sample of 30 clusters was selected in each group. All children aged < 10 years were examined for the diagnosis of active trachoma (trachomatous inflammation which was follicular and/or intense) and the dirtiness of the face and the presence of flies on the face were recorded. The children's carers were questioned about the number of baths given and daily face-washing. Household heads were asked about ownership of cattle and small ruminants. The presence of latrines, a stable, and garbage collection inside the yard was noted. Among 16,514 children examined, 27.0% had active trachoma and 3.3% intense inflammatory trachoma. Flies were present on 11.2% of children's faces and 82.4% and 19.7% of these children had active and intense inflammatory trachoma, respectively. Among the 30.2% of children with dirty faces, 70.2% had active and 10.2% intense inflammatory trachoma. In multivariate analysis, at least one daily bath showed a protective effect on both active and intense inflammatory trachoma. Face-washing twice daily was found to be significantly protective for active trachoma in some regions. A strong association was demonstrated between the presence of flies and dirty faces (odds ratio = 334, 95% confidence interval 202-546). The presence of flies on children's faces, dirty faces and trachoma appeared to be strongly associated. Although the presence of flies may be a marker of socio-economic status and is probably linked with other trachoma risk factors, our data indicated that interventions targeting fly control should be an important issue in controlling trachoma.

A new retinoid-like compound that activates peroxisome proliferator-activated receptors and lowers blood glucose in diabetic mice

Retinoid X receptor (RXR) forms heterodimers with peroxisome proliferator-activated receptors (PPARs, with subtypes of alpha, delta and gamma), and the heterodimers can be activated by either an RXR or a PPAR subtype-specific ligand. Based on the chemical structure of the RXR natural ligand, 9-cis-retinoic acid (9-cis-RA), we designed and synthesized a retinoid-like compound, CS018. In vitro characterizations by cell-based reporter gene assays indicated that CS018 activated RXR homodimers and the heterodimers of RXR with PPARs, but not with farnesoid X-activated receptor (FXR) and liver X-activated receptor (LXR). Furthermore, RT-PCR results showed that CS018 induced the expression of the PPARgamma target genes, CD36 and lipoprotein lipase (LPL). In vivo studies on the diabetic db/db mice demonstrated that CS018 dramatically lowered the animal blood glucose levels. CS018 thus may represent a new retinoid-like compound that activates RXR/PPARs and has potential therapeutic applications in type 2 diabetes and other metabolic diseases.

The CCCTC-binding factor (CTCF)-forkhead box protein M1 axis regulates tumour growth and metastasis in hepatocellular carcinoma

CCCTC‐binding factor (CTCF) is a DNA‐binding protein that interacts with a large number of highly divergent target sequences throughout the genome. It is implicated in a variety of functions, including chromatin organization and transcriptional control. The functional role of CTCF in tumour pathogenesis remains elusive. We showed that CTCF is frequently upregulated in a subset of primary hepatocellular carcinomas (HCCs) as compared with non‐tumoural liver. Overexpression of CTCF was associated with shorter disease‐free survival of patients. Short hairpin RNA (shRNA)‐mediated suppression of CTCF inhibited cell proliferation, motility and invasiveness in HCC cell lines; these effects were correlated with prominent reductions in the expression of telomerase reverse transcriptase (TERT), the shelterin complex member telomerase repeat‐binding factor 1, and forkhead box protein M1 (FOXM1). In contrast, upregulation of CTCF was positively correlated with FOXM1 and TERT expression in clinical HCC biopsies. Depletion of CTCF resulted in reduced motility and invasiveness in HCC cells that could be reversed by ectopic expression of FOXM1, suggesting that FOXM1 is one of the important downstream effectors of CTCF in HCC. Reporter gene analysis suggested that depletion of CTCF is associated with reduced FOXM1 and TERT promoter activity. Chromatin immunoprecipitation (ChIP)–polymerase chain reaction (PCR) analysis further revealed occupancy of the FOXM1 promoter by CTCF in vivo. Importantly, depletion of CTCF by shRNA significantly inhibited tumour progression and metastasis in HCC mouse models. Our work uncovered a novel functional role of CTCF in HCC pathogenesis, which suggests that targeting CTCF could be further explored as a potential therapeutic strategy for HCC. © 2017 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

The needs of physically disabled young people during transition to adult services

OBJECTIVES

The needs and provisions for health service and housing adaptation of a cohort of school leavers with physical disabilities in two inner city London health districts are described in this cross-sectional study.

METHODS

Fourteen young people were assessed by two consultant community paediatricians during their last year at school, using a structured proforma that includes the British Association of Community Child Health standards of functional levels.

RESULTS

Great difficulty was encountered in identifying the subjects, partly because of inadequate information systems. Only 16 were identified out of over 12 000 school leavers. Important discrepancies were found between the needs assessed and the services provided. For the total sample, the need for 49 potential referrals to adult specialist services was identified, but 17 were not made as such services did not exist, in contrast to what had been available within paediatric services. Adult physiotherapy and occupational therapy services were particularly under-provided for young people with physical disabilities. Only a minority were eligible for housing adaptations.

CONCLUSIONS

Suggestions are made for improvements in information systems, the transition process, revised provision of services and closer involvement of general practitioners.

Overlapping nuclei segmentation based on Bayesian networks and stepwise merging strategy

This paper presents a new approach to the segmentation of fluorescence in situ hybridization images. First, to segment the cell nuclei from the background, a threshold is estimated using a Gaussian mixture model and maximizing the likelihood function of the grey values for the cell images. After the nuclei segmentation, the overlapping and isolated nuclei are classified to facilitate a more accurate nuclei analysis. To do this, the morphological features of the nuclei, such their compactness, smoothness and moments, are extracted from training data to generate three probability distribution functions that are then applied to a Bayesian network as evidence. Following the nuclei classification, the overlapping nuclei are segmented into isolated nuclei using an intensity gradient transform and watershed algorithm. A new stepwise merging strategy is also proposed to merge fragments into a major nucleus. Experimental results using fluorescence in situ hybridization images confirm that the proposed system produced better segmentation results when compared to previous methods, because of the nuclei classification before separating the overlapping nuclei.

Do Radiologists Report the TNM Staging in Radiology Reports for Head and Neck Cancers? A National Survey Study

BACKGROUND AND PURPOSE

CT and MR imaging are widely used for the staging of head and neck cancer. Currently, there are no data regarding whether the primary tumor, nodes, metastasis (TNM) staging is routinely incorporated into radiology reports. We conducted a national survey to determine whether radiologists routinely address staging, in particular regarding T (primary tumor) and N (nodal).

MATERIALS AND METHODS

The survey was sent to 782 members of the American Society of Head and Neck Radiology. The survey asked whether they assign TN staging in reports. If they do assign TN staging, what are the reasons for doing so, and if not, what are the barriers or reasons for not including it in the radiology report? The method of measuring the size of the primary tumor and pathologic lymph nodes was also queried.

RESULTS

A total of 229 responses were returned (29.3% response rate). Approximately half (49%; 95% confidence interval, 43.55-54.5%) of the responders thought that incorporating TN staging is important. However, only 24.5% (95% confidence interval, 19.8%-29.2%) stated that they routinely assigned TN staging in their radiology reports. The most common barriers were being afraid of being inaccurate (59%) and being unable to remember the staging classifications (58.2%); 76.9% indicated that they measure a primary tumor in 3D.

CONCLUSIONS

Staging head and neck cancer based on imaging presents unique challenges. Nearly half of the responding radiologists think it is important to incorporate TN staging in radiology reports, though only a quarter of them routinely do so in practice.

Observation of Forward Neutron Multiplicity Dependence of Dimuon Acoplanarity in Ultraperipheral Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The first measurement of the dependence of γγ→μ^{+}μ^{-} production on the multiplicity of neutrons emitted very close to the beam direction in ultraperipheral heavy ion collisions is reported. Data for lead-lead interactions at sqrt[s_{NN}]=5.02  TeV, with an integrated luminosity of approximately 1.5  nb^{-1}, are collected using the CMS detector at the LHC. The azimuthal correlations between the two muons in the invariant mass region 8<m_{μμ}<60  GeV are extracted for events including 0, 1, or at least 2 neutrons detected in the forward pseudorapidity range |η|>8.3. The back-to-back correlation structure from leading-order photon-photon scattering is found to be significantly broader for events with a larger number of emitted neutrons from each nucleus, corresponding to interactions with a smaller impact parameter. This observation provides a data-driven demonstration that the average transverse momentum of photons emitted from relativistic heavy ions has an impact parameter dependence. These results provide new constraints on models of photon-induced interactions in ultraperipheral collisions. They also provide a baseline to search for possible final-state effects on lepton pairs caused by traversing a quark-gluon plasma produced in hadronic heavy ion collisions.

Trends in type 2 diabetes prevalence according to income levels in Korea (1998-2012)

There was no significant association between diabetes prevalence and income levels for either sex in 1998. However, the high income level in men and the low income level in women positively related to the odds of diabetes in 2011-2012. Preventive strategies for diabetes should consider the gender-specific economic discrepancy.

Observation of the Production of Three Massive Gauge Bosons at sqrt[s]=13 TeV

The first observation is reported of the combined production of three massive gauge bosons (VVV with V=W, Z) in proton-proton collisions at a center-of-mass energy of 13 TeV. The analysis is based on a data sample recorded by the CMS experiment at the CERN LHC corresponding to an integrated luminosity of 137  fb^{-1}. The searches for individual WWW, WWZ, WZZ, and ZZZ production are performed in final states with three, four, five, and six leptons (electrons or muons), or with two same-sign leptons plus one or two jets. The observed (expected) significance of the combined VVV production signal is 5.7 (5.9) standard deviations and the corresponding measured cross section relative to the standard model prediction is 1.02_{-0.23}^{+0.26}. The significances of the individual WWW and WWZ production are 3.3 and 3.4 standard deviations, respectively. Measured production cross sections for the individual triboson processes are also reported.

Search for Higgs Boson Decay to a Charm Quark-Antiquark Pair in Proton-Proton Collisions at sqrt[s]=13 TeV

A search for the standard model Higgs boson decaying to a charm quark-antiquark pair, H→cc[over ¯], produced in association with a leptonically decaying V (W or Z) boson is presented. The search is performed with proton-proton collisions at sqrt[s]=13  TeV collected by the CMS experiment, corresponding to an integrated luminosity of 138  fb^{-1}. Novel charm jet identification and analysis methods using machine learning techniques are employed. The analysis is validated by searching for Z→cc[over ¯] in VZ events, leading to its first observation at a hadron collider with a significance of 5.7 standard deviations. The observed (expected) upper limit on σ(VH)B(H→cc[over ¯]) is 0.94 (0.50_{-0.15}^{+0.22})pb at 95% confidence level (C.L.), corresponding to 14 (7.6_{-2.3}^{+3.4}) times the standard model prediction. For the Higgs-charm Yukawa coupling modifier, κ_{c}, the observed (expected) 95% C.L. interval is 1.1<|κ_{c}|<5.5 (|κ_{c}|<3.4), the most stringent constraint to date.

Observation of a New Excited Beauty Strange Baryon Decaying to Ξ_{b}^{-}π^{+}π^{-}

The Ξ_{b}^{-}π^{+}π^{-} invariant mass spectrum is investigated with an event sample of proton-proton collisions at sqrt[s]=13  TeV, collected by the CMS experiment at the LHC in 2016-2018 and corresponding to an integrated luminosity of 140  fb^{-1}. The ground state Ξ_{b}^{-} is reconstructed via its decays to J/ψΞ^{-} and J/ψΛK^{-}. A narrow resonance, labeled Ξ_{b}(6100)^{-}, is observed at a Ξ_{b}^{-}π^{+}π^{-} invariant mass of 6100.3±0.2(stat)±0.1(syst)±0.6(Ξ_{b}^{-})  MeV, where the last uncertainty reflects the precision of the Ξ_{b}^{-} baryon mass. The upper limit on the Ξ_{b}(6100)^{-} natural width is determined to be 1.9  MeV at 95% confidence level. The low Ξ_{b}(6100)^{-} signal yield observed in data does not allow a measurement of the quantum numbers of the new state. However, following analogies with the established excited Ξ_{c} baryon states, the new Ξ_{b}(6100)^{-} resonance and its decay sequence are consistent with the orbitally excited Ξ_{b}^{-} baryon, with spin and parity quantum numbers J^{P}=3/2^{-}.

Associations between earplug use and hearing loss in ROK military personnel

Introduction

The easiest way to prevent noise-induced hearing loss (NIHL) is to wear earplugs. The Republic of Korea (ROK) Ministry of National Defense (MND) is supplying earplugs to prevent NIHL, but many patients still suffer from this. We speculated that earplugs would have a high NIHL rate, depending on the rate of use of earplugs, regardless of the rate of supply. Therefore, we conducted this study to investigate the relationship between the use of earplugs and hearing loss by ROK military personnel.

Methods

The study used data from the Military Health Survey conducted in 2014–2015, which included 13 470 questionnaires completed by ROK military personnel. Hearing loss and earplug use were self-reported. Logistic regression analysis was used to assess associations between earplug use and hearing loss.

Results

The study sample included 13 470 ROK military personnel (response rate of 71.2%) (Army, 8330 (61.8%); Navy/Marines, 2236 (16.6%); and Air Force, 2904 (21.6%)). Overall, 18.8% of Korean military personnel reported that they always wore earplugs, and 2.8% reported hearing loss. In logistic regression analysis, there were significant differences in the rates of hearing loss associated with wearing earplugs sometimes (OR=1.48, 95% CI 1.07 to 2.05) and never wearing earplugs (OR=1.53, 95% CI 1.12 to 2.10). In subgroup analysis, in Air Force, non-combat branch, forward area and long-term military service personnel increased hearing loss was associated with not wearing earplugs.

Conclusion

Our study confirmed that within the ROK military, there is an association between hearing loss and lack of earplug use. In the ROK MND, Army, Navy/Marines and Air Force headquarters must provide guidelines for the use of earplugs during field training to protect military personnel’s hearings and, if necessary, need to be regulated or institutionalised.

Measurement of the Wγ Production Cross Section in Proton-Proton Collisions at sqrt[s]=13 TeV and Constraints on Effective Field Theory Coefficients

A fiducial cross section for Wγ production in proton-proton collisions is measured at a center-of-mass energy of 13 TeV in 137  fb^{-1} of data collected using the CMS detector at the LHC. The W→eν and μν decay modes are used in a maximum-likelihood fit to the lepton-photon invariant mass distribution to extract the combined cross section. The measured cross section is compared with theoretical expectations at next-to-leading order in quantum chromodynamics. In addition, 95% confidence level intervals are reported for anomalous triple-gauge couplings within the framework of effective field theory.

Evidence for Top Quark Production in Nucleus-Nucleus Collisions

Ultrarelativistic heavy ion collisions recreate in the laboratory the thermodynamical conditions prevailing in the early universe up to 10^{-6}  sec, thereby allowing the study of the quark-gluon plasma (QGP), a state of quantum chromodynamics (QCD) matter with deconfined partons. The top quark, the heaviest elementary particle known, is accessible in nucleus-nucleus collisions at the CERN LHC, and constitutes a novel probe of the QGP. Here, we report the first evidence for the production of top quarks in nucleus-nucleus collisions, using lead-lead collision data at a nucleon-nucleon center-of-mass energy of 5.02 TeV recorded by the CMS experiment. Two methods are used to measure the cross section for top quark pair production (σ_{tt[over ¯]}) via the selection of charged leptons (electrons or muons) and bottom quarks. One method relies on the leptonic information alone, and the second one exploits, in addition, the presence of bottom quarks. The measured cross sections, σ_{tt[over ¯]}=2.54_{-0.74}^{+0.84} and 2.03_{-0.64}^{+0.71}  μb, respectively, are compatible with expectations from scaled proton-proton data and QCD predictions.

Measurement of the Inclusive and Differential Higgs Boson Production Cross Sections in the Decay Mode to a Pair of τ Leptons in pp Collisions at sqrt[s]=13 TeV

Measurements of the inclusive and differential fiducial cross sections of the Higgs boson are presented, using the τ lepton decay channel. The differential cross sections are measured as functions of the Higgs boson transverse momentum, jet multiplicity, and transverse momentum of the leading jet in the event, if any. The analysis is performed using proton-proton collision data collected with the CMS detector at the LHC at a center-of-mass energy of 13  TeV and corresponding to an integrated luminosity of 138  fb^{-1}. These are the first differential measurements of the Higgs boson cross section in the final state of two τ leptons. In final states with a large jet multiplicity or with a Lorentz-boosted Higgs boson, these measurements constitute a significant improvement over measurements performed in other final states.

Search for Higgs Boson Pair Production in the Four b Quark Final State in Proton-Proton Collisions at sqrt[s]=13 TeV

A search for pairs of Higgs bosons produced via gluon and vector boson fusion is presented, focusing on the four b quark final state. The data sample consists of proton-proton collisions at a center-of-mass energy of 13 TeV, collected with the CMS detector at the LHC, and corresponds to an integrated luminosity of 138  fb^{-1}. No deviation from the background-only hypothesis is observed. A 95% confidence level upper limit on the Higgs boson pair production cross section is observed at 3.9 times the standard model prediction for an expected value of 7.8. Constraints are also set on the modifiers of the Higgs field self-coupling, κ_{λ}, and of the coupling of two Higgs bosons to two vector bosons, κ_{2 V}. The observed (expected) allowed intervals at the 95% confidence level are -2.3<κ_{λ}<9.4 (-5.0<κ_{λ}<12.0) and -0.1<κ_{2 V}<2.2 (-0.4<κ_{2 V}<2.5). These are the most stringent observed constraints to date on the HH production cross section and on the κ_{2 V } coupling.

Search for Resonances Decaying to Three W Bosons in Proton-Proton Collisions at sqrt[s]=13 TeV

A search for resonances decaying into a W boson and a radion, where the radion decays into two W bosons, is presented. The data analyzed correspond to an integrated luminosity of 138  fb^{-1} recorded in proton-proton collisions with the CMS detector at sqrt[s]=13  TeV. One isolated charged lepton is required, together with missing transverse momentum and one or two massive large-radius jets, containing the decay products of either two or one W bosons, respectively. No excess over the background estimation is observed. The results are combined with those from a complementary channel with an all-hadronic final state, described in an accompanying paper. Limits are set on parameters of an extended warped extra-dimensional model. These searches are the first of their kind at the LHC.