Selective accumulation of mature DC-Lamp+ dendritic cells in tumor sites is associated with efficient T-cell-mediated antitumor response and control of metastatic dissemination in melanoma.

The clinical relevance of dendritic cells (DCs) at the tumor site remains a matter of debate concerning their role in the generation of effective antitumor immunity in human cancers. We performed a comprehensive immunohistochemical analysis using a panel of DC-specific antibodies on regressing tumor lesions and sentinel lymph nodes (SLNs) in melanoma patients. Here we show in a case report involving spontaneous regression of metastatic melanoma that the accumulation of DC-Lamp+ DCs, clustered with tumor cells and lymphocytes, is associated with local expansion of antigen-specific memory effector CTLs. These findings were extended in a series of 19 melanoma-positive SLNs and demonstrated a significant correlation between the density of DC-Lamp+ DC infiltrates in SLNs with the absence of metastasis in downstream lymph nodes. This study, albeit performed in a limited series of patients, points to a pivotal role of mature DCs in the local expansion of efficient antitumor T-cell-mediated immune responses at the initial sites of metastasis and may have important implications regarding the prognosis, staging, and immunotherapy of melanoma patients.

Once-daily dolutegravir is superior to once-daily darunavir/ritonavir in treatment-naïve HIV-1-positive individuals: 96 week results from FLAMINGO.

INTRODUCTION: Dolutegravir (DTG) 50 mg once daily was superior to darunavir/ritonavir (DRV/r) 800 mg/100 mg once daily through Week 48, with 90% vs. 83% of participants achieving HIV RNA 50 c/mL (p=0.025) [1]. We present data through Week 96. MATERIAL AND METHODS: FLAMINGO is a multicentre, randomized, open-label, Phase IIIb non-inferiority study, in which HIV-1-positive ART-naïve adults with HIV-1 RNA≥1000 c/mL and no evidence of viral resistance were randomized 1:1 to receive DTG or DRV/r, with investigator-selected backbone NRTIs (TDF/FTC or ABC/3TC). Participants were stratified by screening HIV-1 RNA (≤100K c/mL) and NRTI backbone. RESULTS: A total of 484 adults were randomized and treated; 25% had baseline HIV RNA 100K c/mL. At Week 96, the proportion of participants with HIV RNA 50 c/mL was 80% in the DTG arm vs. 68% in the DRV/r arm (adjusted difference 12.4%; 95% CI 4.7, 20.2%; p=0.002). Secondary analyses supported primary results: per-protocol [(DTG 83% vs. DRV/r 70%), 95% CI 12.9 (5.3, 20.6)] and treatment-related discontinuation = failure [(98% vs. 95%), 95% CI 3.2 (-0.3, 6.7)]. Overall virologic non-response (DTG 8%; DRV/r 12%) and non-response due to other reasons (DTG 12%; DRV/r 21%) occurred less frequently on DTG. As at Week 48, the difference between arms was most pronounced in participants with high baseline viral load (82% vs. 52% response through Week 96) and in the TDF/FTC stratum (79% vs. 64%); consistent responses were seen in the ABC/3TC stratum (82% vs. 75%). Six participants (DTG 2, none post-Week 48; DRV/r 4, two post-Week 48) experienced protocol-defined virologic failure (PDVF; confirmed viral load 200 c/mL on or after Week 24); none had treatment-emergent resistance to study drugs. Most frequent drug-related adverse events (AEs) were diarrhoea, nausea and headache, with diarrhoea significantly more common on DRV/r (24%) than DTG (10%). Significantly more participants had Grade 2 fasting LDL toxicities on DRV/r (22%) vs. DTG (7%), p<0.001; mean changes in creatinine for DTG (~0.18 mg/dL) observed at Week 2 were stable through Week 96. CONCLUSIONS: Once-daily DTG was superior to once-daily DRV/r in treatment-naïve HIV-1-positive individuals, with no evidence of emergent resistance to DTG in virologic failure and relatively similar safety profiles for DTG and DRV/r through 96 Weeks.

Improving Transition Outcomes: CASE (Career And Self Awareness) Prototype: Basic Points

Basic Points about the CASE (Career And Self Awareness) prototype.

Dynamic price competition with fixed capacities

Many revenue management (RM) industries are characterized by (a) fixed capacities in theshort term (e.g., hotel rooms, seats on an airline flight), (b) homogeneous products (e.g., twoairline flights between the same cities at similar times), and (c) customer purchasing decisionslargely influenced by price. Competition in these industries is also very high even with just twoor three direct competitors in a market. However, RM competition is not well understood andpractically all known implementations of RM software and most published models of RM donot explicitly model competition. For this reason, there has been considerable recent interestand research activity to understand RM competition. In this paper we study price competitionfor an oligopoly in a dynamic setting, where each of the sellers has a fixed number of unitsavailable for sale over a fixed number of periods. Demand is stochastic, and depending on howit evolves, sellers may change their prices at any time. This reflects the fact that firms constantly,and almost costlessly, change their prices (alternately, allocations at a price in quantity-basedRM), reacting either to updates in their estimates of market demand, competitor prices, orinventory levels. We first prove existence of a unique subgame-perfect equilibrium for a duopoly.In equilibrium, in each state sellers engage in Bertrand competition, so that the seller withthe lowest reservation value ends up selling a unit at a price that is equal to the equilibriumreservation value of the competitor. This structure hence extends the marginal-value conceptof bid-price control, used in many RM implementations, to a competitive model. In addition,we show that the seller with the lowest capacity sells all its units first. Furthermore, we extendthe results transparently to n firms and perform a number of numerical comparative staticsexploiting the uniqueness of the subgame-perfect equilibrium.

Positive contrast visualization of iron oxide-labeled stem cells using inversion-recovery with ON-resonant water suppression (IRON)

In proton magnetic resonance imaging (MRI) metallic substances lead to magnetic field distortions that often result in signal voids in the adjacent anatomic structures. Thus, metallic objects and superparamagnetic iron oxide (SPIO)-labeled cells appear as hypointense artifacts that obscure the underlying anatomy. The ability to illuminate these structures with positive contrast would enhance noninvasive MR tracking of cellular therapeutics. Therefore, an MRI methodology that selectively highlights areas of metallic objects has been developed. Inversion-recovery with ON-resonant water suppression (IRON) employs inversion of the magnetization in conjunction with a spectrally-selective on-resonant saturation prepulse. If imaging is performed after these prepulses, positive signal is obtained from off-resonant protons in close proximity to the metallic objects. The first successful use of IRON to produce positive contrast in areas of metallic spheres and SPIO-labeled stem cells in vitro and in vivo is presented.

An European Organisation for Research and Treatment of Cancer phase I study of lapatinib and docetaxel as neoadjuvant treatment for Human Epidermal Growth Factor Receptor 2 (HER2) positive locally-advanced/inflammatory or large operable breast cancer.

BACKGROUND: Lapatinib is an effective anti-HER2 therapy in advanced breast cancer and docetaxel is one of the most active agents in breast cancer. Combining these agents in pre-treated patients with metastatic disease had previously proved challenging, so the primary objective of this study aimed to determine the maximum tolerated dose (MTD) in treatment-naive patients, by identifying acute dose-limiting toxicities (DLT) during cycle 1 in the first part of a phases 1-2 neoadjuvant European Organisation for Research and Treatment of Cancer (EORTC) trial. PATIENTS AND METHODS: Patients with large operable or locally-advanced HER2 positive breast cancer were treated with continuous lapatinib, and docetaxel every 21days for 4 cycles. Dose levels (DLs) were: 1000/75, 1250/75, 1000/85, 1250/85, 1000/100 and 1250/100 (mg/day)/(mg/m(2)). RESULTS: Twenty-one patients were included. Two DLTs occurred at dose level 5 (1000/100); one grade 4 neutropenia ⩾7days and one febrile neutropenia. A further 3 patients were therefore treated at the same dose with prophylactic granulocyte-colony stimulating factor (G-CSF), and 3 patients at dose level 6. No further DLTs were observed. CONCLUSIONS: Our recommended dose for phase II is lapatinib 1000mg/day and docetaxel 100mg/m(2) with G-CSF in HER2 positive non-metastatic breast cancer. The dose of lapatinib should have been 1250mg/day but we were mindful of the high rate of treatment discontinuation in GeparQuinto with lapatinib 1250mg/day combined with docetaxel. No grade 3-4 diarrhoea was observed. Pharmacodynamics analysis suggests that concomitant medications altering P-glycoprotein activity (in addition to lapatinib) can modify toxicity, including non-haematological toxicities. This needs verification in larger trials, where it may contribute to understanding the sources of variability in clinical toxicity and treatment discontinuation.

Employee referrals and efficiency wages

Many workers believe that personal contacts are crucial for obtainingjobs in high-wage sectors. On the other hand, firms in high-wage sectorsreport using employee referrals because they help provide screening andmonitoring of new employees. This paper develops a matching model thatcan explain the link between inter-industry wage differentials and useof employee referrals. Referrals lower monitoring costs because high-effortreferees can exert peer pressure on co-workers, allowing firms to pay lowerefficiency wages. On the other hand, informal search provides fewer job andapplicant contacts than formal methods (e.g., newspaper ads). In equilibrium,the matching process generates segmentation in the labor market becauseof heterogeneity in the size of referral networks. Referrals match good high-paying jobs to well-connected workers, while formal methods matchless attractive jobs to less-connected workers. Industry-level data show apositive correlation between industry wage premia and use of employeereferrals. Moreover, evidence using the NLSY shows similar positive andsignificant OLS and fixed-effects estimates of the returns to employeereferrals, but insignificant effects once sector of employment is controlledfor. This evidence suggests referred workers earn higher wages not becauseof higher unobserved ability or better matches but rather because theyare hired in high-wage sectors.

Fixed-term contracts and the duration distribution of unemployment

In the mid-1980s, many European countries introduced fixed-term contracts.Since then their labor markets have become more dynamic. This paper studiesthe implications of such reforms for the duration distribution ofunemployment, with particular emphasis on the changes in the durationdependence. I estimate a parametric duration model using cross-sectionaldata drawn from the Spanish Labor Force Survey from 1980 to 1994 to analyzethe chances of leaving unemployment before and after the introduction offixed-term contracts. I find that duration dependence has increased sincesuch reform. Semi-parametric estimation of the model also shows that forlong spells, the probability of leaving unemployment has decreased sincesuch reform.

Asymmetric effects of monetary policy in the US: Positive vs. negative or big vs. small?

This paper reconsiders the empirical evidence on the asymmetricoutput effects of monetary policy. Asymmetric effects is a common feature ofmany theoretical models, and there are many different versions of suchasymmetries. We concentrate on the distinctions between positive andnegative money-supply changes, big and small changes in money-supply, andpossible combinations of the two asymmetries. Earlier research has foundempirical evidence in favor of the former of these in US data. Using M1 asthe monetary variable we find evidence in favor of neutrality of big shocksand non-neutrality of small shocks. The results may, however, be affected bystructual instability of M1 demand. Thus, we substitute M1 with the federalfunds rate. In these data we find that only small negative shocks affectreal aggregate activity. The results are interpreted in terms of menu-costmodels.

Comparative genomics of chemosensory protein genes reveals rapid evolution and positive selection in ant-specific duplicates.

Gene duplications can have a major role in adaptation, and gene families underlying chemosensation are particularly interesting due to their essential role in chemical recognition of mates, predators and food resources. Social insects add yet another dimension to the study of chemosensory genomics, as the key components of their social life rely on chemical communication. Still, chemosensory gene families are little studied in social insects. Here we annotated chemosensory protein (CSP) genes from seven ant genomes and studied their evolution. The number of functional CSP genes ranges from 11 to 21 depending on species, and the estimated rates of gene birth and death indicate high turnover of genes. Ant CSP genes include seven conservative orthologous groups present in all the ants, and a group of genes that has expanded independently in different ant lineages. Interestingly, the expanded group of genes has a differing mode of evolution from the orthologous groups. The expanded group shows rapid evolution as indicated by a high dN/dS (nonsynonymous to synonymous changes) ratio, several sites under positive selection and many pseudogenes, whereas the genes in the seven orthologous groups evolve slowly under purifying selection and include only one pseudogene. These results show that adaptive changes have played a role in ant CSP evolution. The expanded group of ant-specific genes is phylogenetically close to a conservative orthologous group CSP7, which includes genes known to be involved in ant nestmate recognition, raising an interesting possibility that the expanded CSPs function in ant chemical communication.

In vitro prevention of the emergence of daptomycin resistance in Staphylococcus aureus and enterococci following combination with amoxicillin/clavulanic acid or ampicillin.

Daptomycin is bactericidal against meticillin-resistant Staphylococcus aureus (MRSA), glycopeptide-intermediate-resistant S. aureus (GISA) and vancomycin-susceptible and -resistant enterococci. However, selection for daptomycin-resistant derivatives has occasionally been reported during therapy in humans. Here we evaluate whether selection for daptomycin-resistant S. aureus or enterococci could be prevented in vitro by combining daptomycin with amoxicillin/clavulanic acid, ampicillin, gentamicin or rifampicin. Six strains of S. aureus (four MRSA and two GISA) and four strains of enterococci (two Enterococcus faecalis and two Enterococcus faecium) were serially exposed in broth to two-fold stepwise increasing concentrations of daptomycin alone or in combination with a fixed concentration [0.25x minimum inhibitory concentration (MIC)] of either of the second agents. The daptomycin MIC was examined after each cycle. Exposure to daptomycin alone gradually selected for S. aureus and enterococci with an increased MIC. Gentamicin did not prevent the emergence of daptomycin-resistant bacteria. Rifampicin was also unable to prevent daptomycin resistance, although resistance was slightly delayed. In contrast, amoxicillin/clavulanic acid or ampicillin prevented or greatly delayed the selection of daptomycin-resistant mutants in S. aureus and enterococci, respectively. Addition of amoxicillin/clavulanic acid or ampicillin to daptomycin prevents, or greatly delays, daptomycin resistance in vitro. Future studies in animal models are needed to predict the utility of these combinations in humans.