Global patterns of allochthony in stream-riparian meta-ecosystems.

Ecosystems that are coupled by reciprocal flows of energy and nutrient subsidies can be viewed as a single "meta-ecosystem." Despite these connections, the reciprocal flow of subsidies is greatly asymmetrical and seasonally pulsed. Here, we synthesize existing literature on stream-riparian meta-ecosystems to quantify global patterns of the amount of subsidy consumption by organisms, known as "allochthony." These resource flows are important since they can comprise a large portion of consumer diets, but can be disrupted by human modification of streams and riparian zones. Despite asymmetrical subsidy flows, we found stream and riparian consumer allochthony to be equivalent. Although both fish and stream invertebrates rely on seasonally pulsed allochthonous resources, we find allochthony varies seasonally only for fish, being nearly three times greater during the summer and fall than during the winter and spring. We also find that consumer allochthony varies with feeding traits for aquatic invertebrates, fish, and terrestrial arthropods, but not for terrestrial vertebrates. Finally, we find that allochthony varies by climate for aquatic invertebrates, being nearly twice as great in arid climates than in tropical climates, but not for fish. These findings are critical to understanding the consequences of global change, as ecosystem connections are being increasingly disrupted.

Reconceptualizing the hyporheic zone for nonperennial rivers and streams.

Nonperennial streams dominate global river networks and are increasing in occurrence across space and time. When surface flow ceases or the surface water dries, flow or moisture can be retained in the subsurface sediments of the hyporheic zone, supporting aquatic communities and ecosystem processes. However, hydrological and ecological definitions of the hyporheic zone have been developed in perennial rivers and emphasize the mixing of water and organisms, respectively, from both the surface stream and groundwater. The adaptation of such definitions to include both humid and dry unsaturated conditions could promote characterization of how hydrological and biogeochemical variability shape ecological communities within nonperennial hyporheic zones, advancing our understanding of both ecosystem structure and function in these habitats. To conceptualize hyporheic zones for nonperennial streams, we review how water sources and surface and subsurface structure influence hydrological and physicochemical conditions. We consider the extent of this zone and how biogeochemistry and ecology might vary with surface states. We then link these components to the composition of nonperennial stream communities. Next, we examine literature to identify priorities for hydrological and ecological research exploring nonperennial hyporheic zones. Lastly, by integrating hydrology, biogeochemistry, and ecology, we recommend a multidisciplinary conceptualization of the nonperennial hyporheic zone as the porous subsurface streambed sediments that shift between lotic, lentic, humid, and dry conditions in space and time to support aquatic-terrestrial biodiversity. As river drying increases in extent because of global change, we call for holistic, interdisciplinary research across the terrestrial and aquatic sciences to apply this conceptualization to characterize hyporheic zone structure and function across the full spectrum of hydrological states.

Energy pathways modulate the resilience of stream invertebrate communities to drought.

While climate change is altering ecosystems on a global scale, not all ecosystems are responding in the same way. The resilience of ecological communities may depend on whether food webs are producer- or detritus-based (i.e. 'green' or 'brown' food webs, respectively), or both (i.e. 'multi-channel' food web). Food web theory suggests that the presence of multiple energy pathways can enhance community stability and resilience and may modulate the responses of ecological communities to disturbances such as climate change. Despite important advances in food web theory, few studies have empirically investigated the resilience of ecological communities to climate change stressors in ecosystems with different primary energy channels. We conducted a factorial experiment using outdoor stream mesocosms to investigate the independent and interactive effects of warming and drought on invertebrate communities in food webs with different energy channel configurations. Warming had little effect on invertebrates, but stream drying negatively impacted total invertebrate abundance, biomass, richness and diversity. Although resistance to drying did not differ among energy channel treatments, recovery and overall resilience were higher in green mesocosms than in mixed and brown mesocosms. Resilience to drying also varied widely among taxa, with larger predatory taxa exhibiting lower resilience. Our results suggest that the effects of drought on stream communities may vary regionally and depend on whether food webs are fuelled by autochthonous or allochthonous basal resources. Communities inhabiting streams with large amounts of organic matter and more complex substrates that provide refugia may be more resilient to the loss of surface water than communities inhabiting streams with simpler, more homogeneous substrates.

River ecosystem conceptual models and non-perennial rivers: A critical review.

Conceptual models underpin river ecosystem research. However, current models focus on continuously flowing rivers and few explicitly address characteristics such as flow cessation and drying. The applicability of existing conceptual models to nonperennial rivers that cease to flow (intermittent rivers and ephemeral streams, IRES) has not been evaluated. We reviewed 18 models, finding that they collectively describe main drivers of biogeochemical and ecological patterns and processes longitudinally (upstream-downstream), laterally (channel-riparian-floodplain), vertically (surface water-groundwater), and temporally across local and landscape scales. However, perennial rivers are longitudinally continuous while IRES are longitudinally discontinuous. Whereas perennial rivers have bidirectional lateral connections between aquatic and terrestrial ecosystems, in IRES, this connection is unidirectional for much of the time, from terrestrial-to-aquatic only. Vertical connectivity between surface and subsurface water occurs bidirectionally and is temporally consistent in perennial rivers. However, in IRES, this exchange is temporally variable, and can become unidirectional during drying or rewetting phases. Finally, drying adds another dimension of flow variation to be considered across temporal and spatial scales in IRES, much as flooding is considered as a temporally and spatially dynamic process in perennial rivers. Here, we focus on ways in which existing models could be modified to accommodate drying as a fundamental process that can alter these patterns and processes across spatial and temporal dimensions in streams. This perspective is needed to support river science and management in our era of rapid global change, including increasing duration, frequency, and occurrence of drying.

What's in a Name? Patterns, Trends, and Suggestions for Defining Non-Perennial Rivers and Streams.

Rivers that cease to flow are globally prevalent. Although many epithets have been used for these rivers, a consensus on terminology has not yet been reached. Doing so would facilitate a marked increase in interdisciplinary interest as well as critical need for clear regulations. Here we reviewed literature from Web of Science database searches of 12 epithets to learn (Objective 1-O1) if epithet topics are consistent across Web of Science categories using latent Dirichlet allocation topic modeling. We also analyzed publication rates and topics over time to (O2) assess changes in epithet use. We compiled literature definitions to (O3) identify how epithets have been delineated and, lastly, suggest universal terms and definitions. We found a lack of consensus in epithet use between and among various fields. We also found that epithet usage has changed over time, as research focus has shifted from description to modeling. We conclude that multiple epithets are redundant. We offer specific definitions for three epithets (non-perennial, intermittent, and ephemeral) to guide consensus on epithet use. Limiting the number of epithets used in non-perennial river research can facilitate more effective communication among research fields and provide clear guidelines for writing regulatory documents.

Zero or not? Causes and consequences of zero-flow stream gage readings.

Streamflow observations can be used to understand, predict, and contextualize hydrologic, ecological, and biogeochemical processes and conditions in streams. Stream gages are point measurements along rivers where streamflow is measured, and are often used to infer upstream watershed-scale processes. When stream gages read zero, this may indicate that the stream has fully dried; however, zero-flow readings can also be caused by a wide range of other factors. Our ability to identify whether or not a zero-flow gage reading indicates a dry fluvial system has far reaching environmental implications. Incorrect identification and interpretation by the data user can lead to hydrologic, ecological, and/or biogeochemical predictions from models and analyses. Here, we describe several causes of zero-flow gage readings: frozen surface water, flow reversals, instrument error, and natural or human-driven upstream source losses or bypass flow. For these examples, we discuss the implications of zero-flow interpretations. We also highlight additional methodss for determining flow presence, including direct observations, statistical methods, and hydrologic models, which can be applied to interpret causes of zero-flow gage readings and implications for reach- and watershed-scale dynamics. Such efforts are necessary to improve our ability to understand and predict surface flow activation, cessation, and connectivity across river networks. Developing this integrated understanding of the wide range of possible meanings of zero-flows will only attain greater importance in a more variable and changing hydrologic climate.

Opioid Stewardship: Building on Antibiotic Stewardship Principles.

The opioid stewardship model is born out of the antimicrobial stewardship model, and thus there are many shared characteristics. Both opioid stewardship and antimicrobial stewardship are based on the principle that there is an indication for a particular medication in the right patient at the right time. As antimicrobial stewardship is in a later stage of development, looking at the two in parallel can lead to interesting learning and development opportunities for opioid stewardship. Two requirements of antimicrobial stewardship that need to be applied to opioid stewardship for optimum outcomes are the requirement for dedicated resources, more specifically a trained pharmacist, and a declaration that opioid stewardship is essential for health-system accreditation.

Convergent synthesis of hydrophilic monomethyl dolastatin 10 based drug linkers for antibody-drug conjugation.

We report a modular approach to synthesize maleimido group containing hydrophilic dolastatin 10 (Dol10) derivatives as drug-linkers for the syntheses of antibody-drug conjugates (ADCs). Discrete polyethylene glycol (PEG) moieties of different chain lengths were introduced as part of the linker to impart hydrophilicity to these drug linkers. The synthesis process involved construction of PEG maleimido derivatives of the tetrapeptide intermediate (N-methylvaline-valine-dolaisoleucine-dolaproine), which were subsequently coupled with dolaphenine to generate the desired drug linkers. The synthetic method reported in this manuscript circumvents the use of highly cytotoxic Dol10 in its native form. By using trastuzumab (Herceptin®) as the antibody we have synthesized Dol10 containing ADCs. The presence of a discrete PEG chain in the drug linkers resulted in ADCs free from aggregation. The effect of PEG chain length on the biological activities of these Dol10 containing ADCs was investigated by in vitro cytotoxicity assays. ADCs containing PEG6 and PEG8 spacers exhibited the highest level of in vitro anti-proliferative activity against HER2-positive (SK-BR-3) human tumor cells. ADCs derived from Herceptin® and PEG8-Dol10, at a dose of 10 mg kg-1, effectively delayed the tumor growth and prolonged the survival time in mice bearing human ovarian SKOV-3 xenografts.

Design, Synthesis, and in†vitro Evaluation of Multivalent Drug Linkers for High-Drug-Load Antibody-Drug Conjugates.

A series of novel multivalent drug linkers (MDLs) containing cytotoxic agents were synthesized and conjugated to antibodies to yield highly potent antibody-drug conjugates (ADCs) with drug/antibody ratios (DARs) higher than those typically reported in the literature (10 vs. ≈4). These MDLs contain two copies of a cytotoxic agent attached to biocompatible scaffolds composed of a branched peptide core and discrete polyethylene glycol (PEG) chains to enhance solubility and decrease aggregation. These drug linkers produced well-defined ADCs, whose DARs could be accurately determined by LC-MS. Using this approach, ADCs with significantly lower aggregation and higher DAR than those of conventional drug linker design were obtained with highly hydrophobic cytotoxic agents such as monomethyldolastatin 10 (MMAD). The in vitro potencies of the MDL-derived conjugates matched that of ADCs of similar DAR with conventional linkers, and the potency increased proportionally with drug loading. This approach may provide a means to prepare highly potent ADCs from a broader range of drugs, including those with lower cytotoxicity or poor solubility, which otherwise limits their use for antibody-drug conjugates. This may also provide a means to further improve the potency achievable with cytotoxins currently used in ADCs.

Mutations in γ-secretase subunit-encoding PSENEN underlie Dowling-Degos disease associated with acne inversa.

Dowling-Degos disease (DDD) is an autosomal-dominant disorder of skin pigmentation associated with mutations in keratin 5 (KRT5), protein O-fucosyltransferase 1 (POFUT1), or protein O-glucosyltransferase 1 (POGLUT1). Here, we have identified 6 heterozygous truncating mutations in PSENEN, encoding presenilin enhancer protein 2, in 6 unrelated patients and families with DDD in whom mutations in KRT5, POFUT1, and POGLUT1 have been excluded. Further examination revealed that the histopathologic feature of follicular hyperkeratosis distinguished these 6 patients from previously studied individuals with DDD. Knockdown of psenen in zebrafish larvae resulted in a phenotype with scattered pigmentation that mimicked human DDD. In the developing zebrafish larvae, in vivo monitoring of pigment cells suggested that disturbances in melanocyte migration and differentiation underlie the DDD pathogenesis associated with PSENEN. Six of the PSENEN mutation carriers presented with comorbid acne inversa (AI), an inflammatory hair follicle disorder, and had a history of nicotine abuse and/or obesity, which are known trigger factors for AI. Previously, PSENEN mutations were identified in familial AI, and comanifestation of DDD and AI has been reported for decades. The present work suggests that PSENEN mutations can indeed cause a comanifestation of DDD and AI that is likely triggered by predisposing factors for AI. Thus, the present report describes a DDD subphenotype in PSENEN mutation carriers that is associated with increased susceptibility to AI.

Optimal management of thumb basal joint arthritis: challenges and solutions.

Up to 15% of the population older than 30 years suffers from symptomatic thumb carpometacarpal (CMC) osteoarthritis (OA), with the incidence increasing to ~33% in postmenopausal women. The thumb CMC joint has been reported as the most painful joint when compared to other hand joints affected by OA. It is therefore no surprise that this is a common chief complaint of patients and has a significant effect on work and life satisfaction. The purpose of this article was to review currently available literature to discuss nonoperative and operative techniques utilized to treat the various stages of thumb CMC arthritis. A variety of nonoperative and operative techniques have been described in the literature, each with its own benefits and pitfalls. This review concludes that while many treatment options exist, there remains no perfect treatment, but the goal of improving quality of life and patient satisfaction remains the same.

Paliperidone palmitate: Japanese postmarketing mortality results in patients with schizophrenia.

OBJECTIVE: Paliperidone palmitate once-monthly injectable (PP1M) is approved in Japan and other countries for the treatment of schizophrenia. During the 6 month Japanese early postmarketing phase vigilance (EPPV) period, 32 deaths were reported. This report reviews potential contributing factors to the fatal outcomes in the PP1M-treated population. RESEARCH DESIGN AND METHODS: All spontaneously reported adverse events following PP1M use received during EPPV from 19 November 2013 to 18 May 2014 were entered into the global safety database and these events were analyzed. RESULTS: During the EPPV period, 10,962 patients were estimated to have been treated with PP1M in Japan. The mortality reporting rate during this EPPV period was higher than that observed in the US or globally after PP1M launch (5.84, 0.43, and 0.38 per 1000 patient-years, respectively), but was consistent with the mortality incidence rates (10.2 per 1000 person-years) observed during interventional clinical studies in Japan and in observational patient cohorts. Of the 32 deaths reported during the Japanese PP1M EPPV period, 19/32 (59.4%) were in patients over 50 years of age, 23/32 (71.9%) reported cardiovascular risk factors and 25/32 (78.1%) received antipsychotic polypharmacy. CONCLUSIONS: Based on this review of the 32 fatal cases in the PP1M EPPV period, the observed death rate does not necessarily result from a risk with PP1M treatment in Japanese patients. The higher mortality reporting rates in Japan may be attributed to a variety of factors: the effectiveness of mortality reporting in the unique Japanese EPPV program, the advanced age of the fatal cases, high cardiovascular risk factors, multiple underlying diseases and high antipsychotic polypharmacy among the cases with fatal outcomes.

Site-specific antibody-drug conjugation through glycoengineering.

Antibody-drug conjugates (ADCs) have been proven clinically to be more effective anti-cancer agents than native antibodies. However, the classical conjugation chemistries to prepare ADCs by targeting primary amines or hinge disulfides have a number of shortcomings including heterogeneous product profiles and linkage instability. We have developed a novel site-specific conjugation method by targeting the native glycosylation site on antibodies as an approach to address these limitations. The native glycans on Asn-297 of antibodies were enzymatically remodeled in vitro using galactosyl and sialyltransferases to introduce terminal sialic acids. Periodate oxidation of these sialic acids yielded aldehyde groups which were subsequently used to conjugate aminooxy functionalized cytotoxic agents via oxime ligation. The process has been successfully demonstrated with three antibodies including trastuzumab and two cytotoxic agents. Hydrophobic interaction chromatography and LC-MS analyses revealed the incorporation of ~1.6 cytotoxic agents per antibody molecule, approximating the number of sialic acid residues. These glyco-conjugated ADCs exhibited target-dependent antiproliferative activity toward antigen-positive tumor cells and significantly greater antitumor efficacy than naked antibody in a Her2-positive tumor xenograft model. These findings suggest that enzymatic remodeling combined with oxime ligation of the native glycans of antibodies offers an attractive approach to generate ADCs with well-defined product profiles. The site-specific conjugation approach presented here provides a viable alternative to other methods, which involve a need to either re-engineer the antibody sequence or develop a highly controlled chemical process to ensure reproducible drug loading.

Micro- and mid-scale maleimide-based conjugation of cytotoxic drugs to antibody hinge region thiols for tumor targeting.

Currently, the principal chemistries for the preparation of antibody-drug conjugates (ADC) target either lysines or cysteines for coupling cytotoxic drugs for delivery to target cells expressing tumor-specific antigens. All of these chemistries generate populations of molecules which differ in critical properties which are known to affect efficacy, pharmacokinetics, and the therapeutic window. Of key interest are methods to minimize this heterogeneity to achieve reproducible product profiles and efficacy. A current trend in the development of ADC is the evaluation of suitable targets, antibodies, and payloads, occurring well before process development to produce conjugates of clinical quality. This creates a need for an ability to generate comparably high-quality products early in development and at sufficient scale for evaluating in vitro potency and in vivo efficacy, as well as the early identification of any deficiencies in critical quality attributes including solubility and stability. Here we elaborate detailed protocols using maleimide-based chemistry for the conjugation to reduce hinge disulfides in antibodies by several cytotoxic drugs. We present a method for the initial characterization of the reduction/alkylation reaction using polyethylene-glycol (PEG) as a drug surrogate, a 5 mg scale drug conjugation to provide material for initial characterization including cell proliferation assays and a 150 mg scale process for performing efficacy studies in small animals. These methods yield well-defined predictable product profiles at high yield and with low impurities. These procedures include details relevant to the execution of these methods in a safe and contained manner within a typical laboratory environment.

Well-defined aminooxy terminated N-(2-hydroxypropyl) methacrylamide macromers for site specific bioconjugation of glycoproteins.

Syntheses and characterization of aminooxy terminated polymers of N-(2-hydroxyproyl) methacrylamide (HPMA) of controlled molecular weight and narrow molecular weight distribution are presented here. Design of a chain transfer agent (CTA) containing N-tert-butoxycarbonyl (t-Boc) protected aminooxy group enabled us to use reversible addition-fragmentation (RAFT) polymerization technique to polymerize the HPMA monomer. An amide bond was utilized to link the aminooxy group and the CTA through a triethylene glycol spacer. As a result, the aminooxy group is linked to the poly(HPMA) backbone through a hydrolytically stable amide bond. By varying the monomer to initiator ratios, polymers with targeted molecular weights were obtained. The molecular weights of the polymers were determined by gel permeation chromatography (GPC) and mass spectrometry (ESI and MALDI-TOF). The t-Boc protecting group was quantitatively removed to generate aminooxy terminated poly(HPMA) macromers. These macromers were converted to rhodamine B terminated poly(HPMA) by reacting N-hydroxysuccinimide (NHS) ester of the dye with the terminal aminooxy group to form a stable alkoxyamide bond. Utility of these dye-labeled polymers as molecular probes was evaluated by fluorescence microscopy by studying their intracellular uptake by renal epithelial cells. These aminooxy terminated poly(HPMA) were also tested as biocompatible carriers to prepare chemoselective bioconjugates of proteins using transferrin (Tf) as the protein. Oxidation of the sialic acid side chains of Tf generated aldehyde functionalized protein that was reacted with aminooxy terminated poly(HPMA), which resulted in protein-polymer bioconjugates carrying oxime linkages. These bioconjugates were characterized by gel electrophoresis and MALDI-TOF mass spectrometry.

Identification and quantitation of Vesivirus 2117 particles in bioreactor fluids from infected Chinese hamster ovary cell cultures.

The prevention of adventitious agent contamination is a top priority throughout the entire biopharmaceutical production process. For example, although viral contamination of cell banks or cell cultures is rare, it can result in serious consequences (e.g., shutdown and decontamination of manufacturing facilities). To ensure virus free production, numerous in vivo and in vitro adventitious agent assays and biophysical characterizations such as electron microscopy are conducted on cell banks, raw materials, process materials, and drug substances throughout the manufacturing process. Molecular assays such as PCR and other nucleotide-based techniques are also routinely used for screening and identification of any viral agents. However, modern techniques in protein identification of complex protein mixtures have not yet been effectively integrated throughout the industry into current viral testing strategies. Here, we report the identification and quantitation of Vesivirus 2117 particles in bioreactor fluid from infected Chinese hamster ovary cell cultures by global protein sequencing using mass spectrometry in combination with multi-dimensional liquid-chromatography. Following mass spectrometric data acquisition and rigorous data analysis, six virus specific peptides were identified. These peptides were fragments of two structural proteins, capsid protein pre-cursor (four unique peptides) and small structural protein (two unique peptides), from the same species: Vesivirus 2117. Using stable heavy isotope-labeled peptides as internal standards, we also determined the absolute concentration of Vesivirus particles in the bioreactor fluid and the ratio of two capsid proteins (VP1:VP2) in the particles as approximately 9:1. The positive identification of Vesivirus 2117 was subsequently confirmed by RT-PCR.

Serum (1→3)-ß-D-glucan levels in HIV-infected individuals are associated with immunosuppression, inflammation, and cardiopulmonary function.

BACKGROUND: Translocation of gastrointestinal bacteria in HIV-infected individuals is associated with systemic inflammation, HIV progression, mortality, and comorbidities. HIV-infected individuals are also susceptible to fungal infection and colonization, but whether fungal translocation occurs and influences HIV progression or comorbidities is unknown. METHODS: Serum (1→3)-ß-D-glucan (BG) was measured by a Limulus Amebocyte Lysate assay (Fungitell) in 132 HIV-infected outpatients. Selected plasma cytokines and markers of peripheral T-cell activation were measured. Pulmonary function testing and Doppler echocardiography were performed. Relationship of high (≥40 pg/mL) and low (<40 pg/mL) levels of BG with HIV-associated variables, inflammation markers, and pulmonary function and pulmonary hypertension measures were determined. RESULTS: Forty-eight percent of patients had detectable BG, and 16.7% had high levels. Individuals with high BG were more likely to have CD4 counts less than 200 cells/µL (31.8% vs. 8.4%, P = 0.002), had higher log10 HIV viral levels (2.85 vs. 2.13 log copies/mL, P = 0.004), and were less likely to use antiretroviral therapy (68.2% vs. 90.0%, P = 0.006). Plasma IL-8 (P = 0.033), TNF-α (P = 0.029), and CD8CD38 (P = 0.046) and CD8HLA-DR (P = 0.029) were also increased with high levels. Abnormalities in diffusing capacity (P = 0.041) and in pulmonary artery pressures (P = 0.006 for pulmonary artery systolic pressure and 0.013 for tricuspid regurgitant velocity) were more common in those with high BG. CONCLUSIONS: We found evidence of peripheral fungal cell wall polysaccharides in an HIV-infected cohort. We also demonstrated an association between high serum BG, HIV-associated immunosuppression, inflammation, and cardiopulmonary comorbidity. These results implicate a new class of pathogen in HIV-associated microbial translocation and suggest a role in HIV progression and comorbidities.

Targeting HER2-positive cancer with dolastatin 15 derivatives conjugated to trastuzumab, novel antibody-drug conjugates.

PURPOSE: Targeting tubulin binders to cancer cells using antibody-drug conjugates (ADCs) has great potential to become an effective cancer treatment with low normal tissue toxicity. The nature of the linker used to tether the tubulin binder to the antibody and the conjugation sites on the antibody and the small molecule are important factors in the ADC stability and effectiveness. METHODS: We explored the use of tubulin-targeting dolastatin 15 derivatives (Dol15) tethered covalently to a representative antibody, trastuzumab, via cleavable and non-cleavable linkers at varying antibody reactive sites (i.e., lysine residues, partially reduced hinge region disulfide bonds) and drug coupling sites (i.e., C-terminus, N-terminus), to investigate which constructs were more effective in killing HER2-positive cells in vitro and in vivo. RESULTS: We found that Dol15 conjugated to trastuzumab via lysine residues at the drug C-terminus using a non-cleavable linker (trastuzumab-amide-C-term-Dol15) produced target-dependent growth inhibition of cells endogenously expressing high HER2 levels (i.e., SK-BR-3, SK-OV-3) in vitro. This ADC was effective at varying doses (i.e., 10 and 20 mg/kg) in the SK-OV-3 human ovarian cancer xenograft. CONCLUSIONS: Tethering Dol15 via partially reduced disulfide bonds at the drug C-terminus via a non-cleavable linker (trastuzumab-MC-C-term-Dol15) resulted in an equally effective ADC in vitro, showing that site of antibody conjugation did not influence ADC activity. However, tethering Dol15 at the drug N-terminus using non-cleavable and cleavable linkers (trastuzumab-MC-N-term-Dol15 and trastuzumab-MC-VC-PABC-N-term-Dol15, respectively) resulted in ineffective ADCs. Thus, Dol15 tethered at the C-terminus may be a useful tubulin-targeting agent for conjugation at various antibody reactive sites.

Cardiopulmonary function in individuals with HIV infection in the antiretroviral therapy era.

OBJECTIVE: To determine relationship of echocardiographic measures of pulmonary hypertension to lung function and inflammatory biomarkers in HIV-infected individuals. DESIGN: Cross-sectional study of 116 HIV-infected outpatients. METHODS: Doppler-echocardiography and pulmonary function testing were performed. Induced sputum and plasma cytokines, sputum cell counts and differentials, markers of peripheral T-cell activation, and serum N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured. Univariate and multivariate analyses determined relationship of echocardiographic variables to pulmonary function, inflammation, and NT-proBNP. RESULTS: Mean estimated pulmonary artery systolic pressure (PASP) was 34.3 mmHg (SD 6.9) and mean tricuspid regurgitant jet velocity (TRV) was 2.5 m/s (SD 0.32). Eighteen participants (15.5%) had PASP of at least 40 mmHg, and nine (7.8%) had TRV of at least 3.0 m/s. Elevated TRV was significantly associated with CD4 cell counts below 200 cells/µl and higher log HIV-RNA levels. Forced expiratory volume in 1 s (FEV(1)) percentage predicted, FEV(1)/forced vital capacity, and diffusing capacity for carbon monoxide (DLco) percentage predicted were significantly lower in those with elevated PASP or TRV. Sputum interleukin-8, peripheral interleukin-8, peripheral interferon-γ levels, and CD8(+) T-cell expression of CD69(+) were associated with increasing PASP and TRV. Log NT-proBNP was significantly higher with increasing PASP and TRV. Left ventricular function was not associated with PASP or TRV. CONCLUSION: Echocardiographic manifestations of pulmonary hypertension are common in HIV and are associated with respiratory symptoms, more advanced HIV disease, airway obstruction, abnormal DLco, and systemic and pulmonary inflammation. Pulmonary hypertension and chronic obstructive pulmonary disease coexist in HIV and may arise secondary to common inflammatory mechanisms.

Asthma diagnosis and airway bronchodilator response in HIV-infected patients.

BACKGROUND: Despite the high prevalence of respiratory symptoms and obstructive lung disease in HIV-infected subjects, the prevalence of bronchodilator reversibility (BDR) and asthma has not been systematically studied during the era of combination antiretroviral therapy (ART). OBJECTIVE: We sought to determine the prevalence of asthma diagnosis and related pulmonary function abnormalities in an HIV-infected cohort and to identify potential mechanisms. METHODS: We performed a cross-sectional analysis of 223 HIV-infected subjects with data on respiratory symptoms and diagnoses, pulmonary function, sputum cell counts, and asthma-related cytokines and chemokines in serum/sputum. RESULTS: Doctor-diagnosed asthma was present in 46 (20.6%), and BDR (≥200 mL and ≥12% increase in FEV(1) or forced vital capacity) was present in 20 (9.0%) participants. Pulmonary symptoms and function were worse in those with doctor-diagnosed asthma. Doctor-diagnosed asthma was independently associated with female sex (P = .04), body mass index of greater than 29.6 kg/m(2) (vs <29.6 kg/m(2), P = .03), history of bacterial or Pneumocystis pneumonia (P = .01), and not currently taking ART (P = .04) and in univariate analysis with parental history of asthma (n = 180, P = .004). High sputum eosinophil percentages (>2.3% based on the highest decile) were more likely in those with doctor-diagnosed asthma (P = .02) or BDR (P = .02). Doctor-diagnosed asthma tended to be more common with high sputum IL-4 (P = .02) and RANTES (P = .02) levels, whereas BDR was associated with high plasma macrophage inflammatory protein 1α (P = .002) and sputum macrophage inflammatory protein 1ß (P = .001) levels. CONCLUSION: Asthma diagnosis and BDR are prevalent in an HIV-infected outpatient cohort, and associations with family history, obesity, allergic inflammation, prior infection, absence of ART, and increased HIV-stimulated cytokines suggest possible mechanisms of HIV-associated asthma.