Hypoxia drives murine neutrophil protein scavenging to maintain central carbon metabolism

Limiting dysfunctional neutrophilic inflammation while preserving effective immunity requires a better understanding of the processes that dictate neutrophil function in the tissues. Quantitative mass-spectrometry identified how inflammatory murine neutrophils regulated expression of cell surface receptors, signal transduction networks, and metabolic machinery to shape neutrophil phenotypes in response to hypoxia. Through the tracing of labeled amino acids into metabolic enzymes, proinflammatory mediators, and granule proteins, we demonstrated that ongoing protein synthesis shapes the neutrophil proteome. To maintain energy supplies in the tissues, neutrophils consumed extracellular proteins to fuel central carbon metabolism. The physiological stresses of hypoxia and hypoglycemia, characteristic of inflamed tissues, promoted this extracellular protein scavenging with activation of the lysosomal compartment, further driving exploitation of the protein-rich inflammatory milieu. This study provides a comprehensive map of neutrophil proteomes, analysis of which has led to the identification of active catabolic and anabolic pathways that enable neutrophils to sustain synthetic and effector functions in the tissues.     

Deep Artificial Neural Networks Reveal a Distributed Cortical Network Encoding Propositional Sentence-Level Meaning

Understanding how and where in the brain sentence-level meaning is constructed from words presents a major scientific challenge. Recent advances have begun to explain brain activation elicited by sentences using vector models of word meaning derived from patterns of word co-occurrence in text corpora. These studies have helped map out semantic representation across a distributed brain network spanning temporal, parietal, and frontal cortex. However, it remains unclear whether activation patterns within regions reflect unified representations of sentence-level meaning, as opposed to superpositions of context-independent component words. This is because models have typically represented sentences as “bags-of-words” that neglect sentence-level structure. To address this issue, we interrogated fMRI activation elicited as 240 sentences were read by 14 participants (9 female, 5 male), using sentences encoded by a recurrent deep artificial neural-network trained on a sentence inference task (InferSent). Recurrent connections and nonlinear filters enable InferSent to transform sequences of word vectors into unified “propositional” sentence representations suitable for evaluating intersentence entailment relations. Using voxelwise encoding modeling, we demonstrate that InferSent predicts elements of fMRI activation that cannot be predicted by bag-of-words models and sentence models using grammatical rules to assemble word vectors. This effect occurs throughout a distributed network, which suggests that propositional sentence-level meaning is represented within and across multiple cortical regions rather than at any single site. In follow-up analyses, we place results in the context of other deep network approaches (ELMo and BERT) and estimate the degree of unpredicted neural signal using an “experiential” semantic model and cross-participant encoding.SIGNIFICANCE STATEMENT A modern-day scientific challenge is to understand how the human brain transforms word sequences into representations of sentence meaning. A recent approach, emerging from advances in functional neuroimaging, big data, and machine learning, is to computationally model meaning, and use models to predict brain activity. Such models have helped map a cortical semantic information-processing network. However, how unified sentence-level information, as opposed to word-level units, is represented throughout this network remains unclear. This is because models have typically represented sentences as unordered “bags-of-words.” Using a deep artificial neural network that recurrently and nonlinearly combines word representations into unified propositional sentence representations, we provide evidence that sentence-level information is encoded throughout a cortical network, rather than in a single region.     

Gene transfer to primary normal and malignant human hemopoietic progenitors using recombinant retroviruses

To study the feasibility of using retroviruses for gene transfer into human hemopoietic cells, various cell types were exposed to virus carrying the gene for neomycin resistance (neor). In preliminary studies using K562 cells as targets, we found that high viral titer and co-cultivation with viral producer cells rather than incubation in medium exposed to viral producer cells were important variables for achieving high frequencies of G418 resistant (G418r) colonies. The maximum frequency of G418r K562 colonies after co-cultivation with cells producing a neor virus titer of 4 X 10(6) cfu/mL was 60%. When primary human progenitors from normal marrow, fetal liver, or chronic myelogenous leukemia blood were exposed to high titer viral stocks, both with and without helper virus, under conditions optimized for K562 cells, maximum frequencies of G418r colonies were 3% to 16% for granulocyte macrophage progenitors and 2% to 6% for primitive erythroid progenitors. The presence of the neor gene in both G418r K562 and primary hemopoietic colonies was verified by Southern blot. Expression of the neor gene was shown by RNA spot blot. These data demonstrate efficient transfer and expression of the neor gene in both K562 cells and primary human hemopoietic cells from normal and leukemic individuals.     

In Vitro Activity of Daptomycin in Combination with β-Lactams,Gentamicin, Rifampin,and Tigecycline against Daptomycin-Nonsusceptible Enterococci

Enterococci that are nonsusceptible (NS; MIC > 4 μg/ml) to daptomycin are an emerging clinical concern. The synergistic combination of daptomycin plus beta-lactams has been shown to be effective against vancomycin-resistant Enterococcus (VRE) species in vitro. This study systematically evaluated by in vitro time-kill studies the effect of daptomycin in combination with ampicillin, cefazolin, ceftriaxone, ceftaroline, ertapenem, gentamicin, tigecycline, and rifampin, for a collection of 9 daptomycin-NS enterococci that exhibited a broad range of MICs and different resistance-conferring mutations. We found that ampicillin plus daptomycin yielded the most consistent synergy but did so only for isolates with mutations to the liaFSR system. Daptomycin binding was found to be enhanced by ampicillin in a representative isolate with such mutations but not for an isolate with mutation to the yycFGHIJ system. In contrast, ampicillin enhanced the killing of the LL-37 human antimicrobial peptide against daptomycin-NS E. faecium with either the liaFSR or yycFGHIJ mutation. Antagonism was noted only for rifampin and tigecycline and only for 2 or 3 isolates. These data add support to the growing body of evidence indicating that therapy combining daptomycin and ampicillin may be helpful in eradicating refractory VRE infections.     

First Report of Ceftazidime-Avibactam Resistance in a KPC-3-Expressing Klebsiella pneumoniae Isolate

Ceftazidime-avibactam is the first antimicrobial approved by the U.S. FDA for the treatment of carbapenem-resistant Enterobacteriaceae. Avibactam, a non-β-lactam β-lactamase inhibitor, inactivates class A serine carbapenemases, including Klebsiella pneumoniae carbapenemase (KPC). We report a KPC-producing K. pneumoniae isolate resistant to ceftazidime-avibactam (MIC, 32/4 μg/ml) from a patient with no prior treatment with ceftazidime-avibactam.     

Cardiovascular comorbidities are increased in US patients with haemophilia A: a retrospective database analysis

There is conflicting evidence in the literature on whether individuals with haemophilia in the USA have greater, reduced, or similar risks for cardiovascular disease as the general population. This study evaluated the prevalence of cardiovascular comorbidities among USA males with haemophilia A, relative to an unaffected general male population with similar characteristics. Males with haemophilia A and continuous insurance coverage were identified by ICD‐9‐CM code 286.0 (1 January 2007–31 December 2009) using the MarketScan^® Commercial and Medicare Research Databases. Individuals with haemophilia A were exact matched 1:3 with males without a diagnosis of haemophilia A. The prevalence of cardiovascular comorbidities identified by ICD‐9‐CM code was determined for matched cohorts. Of the study population, 2506 were grouped in the haemophilia A cohort and 7518 in the general cohort. Proportions of individuals with haemorrhagic stroke (2.0% vs. 0.5%, P < 0.001), ischemic stroke (4.7% vs. 2.7%, P < 0.001), coronary artery disease (10.7% vs. 5.8%, P < 0.001), myocardial infarction (0.8% vs. 0.3%, P = 0.003), hypertension (22.6% vs. 15.5%, P < 0.001), hyperlipidaemia (15.9% vs. 11.9%, P < 0.001), arterial thrombosis (12.1% vs. 5.9%, P < 0.001), and venous thrombosis (4.4% vs. 1.1%, P < 0.001) were significantly greater for the haemophilia A cohort. Results were consistent across most age groups, and comorbidities appeared at an earlier age in those with haemophilia A than in the general population. Among the USA haemophilia A population cardiovascular comorbidities are more prevalent and they appear earlier in life in comparison to the general male population, suggesting the need for earlier, enhanced screening for age‐related comorbidities in the haemophilia community.     

Age-related differences in spontaneous trait judgments from facial appearance

We tested whether there are age-related declines in detecting cues to trustworthiness, a skill that has been demonstrated to be rapid and automatic in younger adults. Young (M_age = 21.2 years) and older (M_age = 70.15 years) adults made criminal appearance judgments to unfamiliar faces, which were presented at a duration of 100, 500 or 1,000 ms. Participants’ response times and judgment confidence were recorded. Older were poorer than young adults at judging trustworthiness at 100 ms, and were slower overall in making their judgments. Further, the cues (i.e. perceptions of anger, trustworthiness and happiness) underlying criminality judgments were the same across age groups. Judgment confidence increased with increasing exposure duration for both age groups, while older adults were less confident in their judgments overall than their young counterparts. The implications are discussed.     

Causes of dissatisfaction after laparoscopic fundoplication: the impact of new symptoms, recurrent symptoms, and the patient experience

Background

Although laparoscopic fundoplication effectively alleviates gastroesophageal reflux disease (GERD) in the great majority of patients, some patients remain dissatisfied after the operation. This study was undertaken to report the outcomes of these patients and to determine the causes of dissatisfaction after laparoscopic fundoplication.

Methods

All patients undergoing laparoscopic fundoplication in the authors’ series from 1992 to 2010 were evaluated for frequency and severity of symptoms before and after laparoscopic fundoplication, and their experiences were graded from “very satisfying” to “very unsatisfying.” Objective outcomes were determined by endoscopy, barium swallow, and pH monitoring. Primary complaints were derived from postoperative surveys. Median data are reported.

Results

Of the 1,063 patients undergoing laparoscopic fundoplication, 101 patients reported dissatisfaction after the procedure. The follow-up period was 33 months. The dissatisfied patients (n = 101) were more likely than the satisfied patients to have postoperative complications (9 vs 4 %; p < 0.05) and to have undergone a prior fundoplication (22 vs 11 %; p < 0.05). For the dissatisfied patients, heartburn decreased in frequency and severity after fundoplication (p < 0.05) but remained notable. Also for the dissatisfied patients, new symptoms (gas bloat/dysphagia) were the most prominent postoperative complaint (59 %), followed by symptom recurrence (23 %), symptom persistence (4 %), and the overall experience (14 %). Primary complaints of new symptoms were most common within the first year of follow-up assessment and less frequent thereafter. Primary complaints of recurrent symptoms generally occurred more than 1 year after fundoplication.

Conclusions

Dissatisfaction is uncommon after laparoscopic fundoplication. New symptoms, such as dysphagia and gas/bloating, are primary causes of dissatisfaction despite general reflux alleviation among these patients. New symptoms occur sooner after fundoplication than recurrent symptoms and may become less common with time.