Topical Tranexamic Acid to Control Vaginal Laceration Bleeding after Sexual Assault.

BACKGROUND: Sexual assault survivors may sustain vaginal trauma that requires intervention in the emergency department, or operating room. CASE REPORT: We describe the case of a 16-year-old female who was referred to the emergency department for evaluation of continued bleeding from a vaginal laceration following sexual assault 38 h prior. The bleeding limited the medical forensic medical examination, but she was hemodynamically stable. After the application of tranexamic acid (TXA)-soaked gauze, the patient's bleeding was controlled and the wound was able to be evaluated and the examination completed. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: To our knowledge, this is the first case in the literature that describes the use of topical TXA in a patient to achieve hemostasis in a vaginal laceration sustained from sexual violence.

Artificial Intelligence Algorithm Improves Radiologist Performance in Skeletal Age Assessment: A Prospective Multicenter Randomized Controlled Trial.

Background Previous studies suggest that use of artificial intelligence (AI) algorithms as diagnostic aids may improve the quality of skeletal age assessment, though these studies lack evidence from clinical practice. Purpose To compare the accuracy and interpretation time of skeletal age assessment on hand radiograph examinations with and without the use of an AI algorithm as a diagnostic aid. Materials and Methods In this prospective randomized controlled trial, the accuracy of skeletal age assessment on hand radiograph examinations was performed with (n = 792) and without (n = 739) the AI algorithm as a diagnostic aid. For examinations with the AI algorithm, the radiologist was shown the AI interpretation as part of their routine clinical work and was permitted to accept or modify it. Hand radiographs were interpreted by 93 radiologists from six centers. The primary efficacy outcome was the mean absolute difference between the skeletal age dictated into the radiologists' signed report and the average interpretation of a panel of four radiologists not using a diagnostic aid. The secondary outcome was the interpretation time. A linear mixed-effects regression model with random center- and radiologist-level effects was used to compare the two experimental groups. Results Overall mean absolute difference was lower when radiologists used the AI algorithm compared with when they did not (5.36 months vs 5.95 months; P = .04). The proportions at which the absolute difference exceeded 12 months (9.3% vs 13.0%, P = .02) and 24 months (0.5% vs 1.8%, P = .02) were lower with the AI algorithm than without it. Median radiologist interpretation time was lower with the AI algorithm than without it (102 seconds vs 142 seconds, P = .001). Conclusion Use of an artificial intelligence algorithm improved skeletal age assessment accuracy and reduced interpretation times for radiologists, although differences were observed between centers. Clinical trial registration no. NCT03530098 © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Rubin in this issue.

Protection by and maintenance of CD4 effector memory and effector T cell subsets in persistent malaria infection.

Protection at the peak of Plasmodium chabaudi blood-stage malaria infection is provided by CD4 T cells. We have shown that an increase in Th1 cells also correlates with protection during the persistent phase of malaria; however, it is unclear how these T cells are maintained. Persistent malaria infection promotes protection and generates both effector T cells (Teff), and effector memory T cells (Tem). We have previously defined new CD4 Teff (IL-7Rα-) subsets from Early (TeffEarly, CD62LhiCD27+) to Late (TeffLate, CD62LloCD27-) activation states. Here, we tested these effector and memory T cell subsets for their ability to survive and protect in vivo. We found that both polyclonal and P. chabaudi Merozoite Surface Protein-1 (MSP-1)-specific B5 TCR transgenic Tem survive better than Teff. Surprisingly, as Tem are associated with antigen persistence, Tem survive well even after clearance of infection. As previously shown during T cell contraction, TeffEarly, which can generate Tem, also survive better than other Teff subsets in uninfected recipients. Two other Tem survival mechanisms identified here are that low-level chronic infection promotes Tem both by driving their proliferation, and by programming production of Tem from Tcm. Protective CD4 T cell phenotypes have not been precisely determined in malaria, or other persistent infections. Therefore, we tested purified memory (Tmem) and Teff subsets in protection from peak pathology and parasitemia in immunocompromised recipient mice. Strikingly, among Tmem (IL-7Rαhi) subsets, only TemLate (CD62LloCD27-) reduced peak parasitemia (19%), though the dominant memory subset is TemEarly, which is not protective. In contrast, all Teff subsets reduced peak parasitemia by more than half, and mature Teff can generate Tem, though less. In summary, we have elucidated four mechanisms of Tem maintenance, and identified two long-lived T cell subsets (TemLate, TeffEarly) that may represent correlates of protection or a target for longer-lived vaccine-induced protection against malaria blood-stages.

Early Inhibition of Fatty Acid Synthesis Reduces Generation of Memory Precursor Effector T Cells in Chronic Infection.

Understanding the mechanisms of CD4 memory T cell (Tmem) differentiation in malaria is critical for vaccine development. However, the metabolic regulation of CD4 Tmem differentiation is not clear, particularly in persistent infections. In this study, we investigated the role of fatty acid synthesis (FAS) in Tmem development in Plasmodium chabaudi chronic mouse malaria infection. We show that T cell-specific deletion and early pharmaceutical inhibition of acetyl CoA carboxylase 1, the rate limiting step of FAS, inhibit generation of early memory precursor effector T cells (MPEC). To compare the role of FAS during early differentiation or survival of Tmem in chronic infection, a specific inhibitor of acetyl CoA carboxylase 1, 5-(tetradecyloxy)-2-furoic acid, was administered at different times postinfection. Strikingly, the number of Tmem was only reduced when FAS was inhibited during T cell priming and not during the Tmem survival phase. FAS inhibition during priming increased effector T cell (Teff) proliferation and strongly decreased peak parasitemia, which is consistent with improved Teff function. Conversely, MPEC were decreased, in a T cell-intrinsic manner, upon early FAS inhibition in chronic, but not acute, infection. Early cure of infection also increased mitochondrial volume in Tmem compared with Teff, supporting previous reports in acute infection. We demonstrate that the MPEC-specific effect was due to the higher fatty acid content and synthesis in MPEC compared with terminally differentiated Teff. In conclusion, FAS in CD4 T cells regulates the early divergence of Tmem from Teff in chronic infection.

The grammaticality asymmetry in agreement attraction reflects response bias: Experimental and modeling evidence.

Memory access mechanisms such as cue-based retrieval have come to dominate theories of the processing of linguistic dependencies such as subject-verb agreement. One phenomenon that has been regarded as demonstrating the role of such mechanisms is the grammaticality asymmetry in agreement attraction, which is the observation that nouns other than the grammatical controller of agreement can influence the computation of subject-verb agreement in ungrammatical, but not grammatical, sentences. This asymmetry is most often accounted for via the dynamics of retrieval interference. We challenge this interpretation, arguing that the asymmetry largely reflects response bias. Three forced-choice judgment experiments show that neutralizing response bias results in a decrease in the size of the grammaticality asymmetry, or its elimination altogether. Together with the response time patterns in these experiments, this result favors an account that attributes attraction effects to a continuous and equivocal representation of number, rather than to the dynamics of retrieval interference. We implement a model of grammaticality judgments that links a continuous representation of number to the rate of evidence accumulation in a diffusion process. This model accounts for the presence or absence of the grammaticality asymmetry through shifts in the decisional starting point (i.e. response bias), and highlights the importance of monitoring for response bias effects in judgment tasks.

Processing of Norwegian complex verbs: Evidence for early decomposition.

We examined the processing of Norwegian complex verbs-compounds consisting of a prepositional prefix and a verbal root-to investigate the lexical decomposition of such morphologically complex compounds. In an eyetracking-while-reading study, we tested whether reading time measures were significantly predicted by a compound verb's whole-word frequency, its root family frequency, or some combination thereof. The results suggest that whole-word and root family frequencies make independent contributions to first-fixation durations. Subsequent reading time measures were better predicted by either whole-word frequency, root family frequency, or both in tandem. We interpret these results as providing support for hybrid models of lexical representation, in which complex verbs are associated with an atomic (whole-word) representation linked to the lexical entries for the compound's constituent morphemes.

Growing and Learning When Consumption Is Seasonal: Long-Term Evidence From Tanzania.

This article shows that the seasonality of food consumption during childhood, conditional on average consumption, affects long-run human capital development. We develop a model that distinguishes differences in average consumption levels, seasonal fluctuations, and idiosyncratic shocks, and estimate the model using panel data from early 1990s Tanzania. We then test whether the mean and seasonality of a child's consumption profile affect height and educational attainment in 2010. Results show that the negative effects of greater seasonality are 30 % to 60 % of the magnitudes of the positive effects of greater average consumption. Put differently, children expected to have identical human capital based on annualized consumption measures will have substantially different outcomes if one child's consumption is more seasonal. We discuss implications for measurement and policy.

Acute Limb Ischemia in an 8-Year-Old Patient: A Case Report.

We report the case of an 8-year-old patient with a history of nephrotic syndrome, who presented to the emergency department with right foot pain. The patient's mother described intermittent pain that woke her son from sleep and was accompanied by the foot turning purple and becoming cold to touch. Physical examination revealed capillary refill of over 10 seconds in the right and less than 2 seconds in the left foot. Ankle-brachial indices (ABIs) were 0.0 on the right and 0.96 on the left. The patient was admitted and started on therapeutic intravenous heparin. After consultation with his parents, right lower extremity angiography and thrombolysis was performed over 2 days. He subsequently underwent fasciotomy and amputation of the tip of all 5 toes. Eighteen months later, there is no leg length discrepancy, he is walking with foot inserts and has normal ABIs bilaterally.

Effects of Mechanical Complications on Radiation Exposure During Fluoroscopically Guided Gastrojejunostomy Exchange in the Pediatric Population.

The purpose of the article is to evaluate the effects of mechanical complications, such as clogging or coiling, of gastrojejunostomy tubes on radiation exposure during exchange in the pediatric population. In this HIPAA-compliant and IRB-approved study, we retrospectively reviewed procedural records for patients undergoing gastrojejunostomy (GJ) tube exchange during a 4-month period in 2014. Success of the procedure, specifications of the tube, age, and sex of the patient as well as radiation exposure during the procedure were included. Radiation exposure was measured in fluoroscopy time and cumulative air kerma. Complications encountered during exchange were also recorded, if available. Patients presenting for gastrostomy to GJ conversions or combined procedures were excluded from the study. Ordinary and mixed effect linear regression models were used to test associations between GJ tube parameters, presence of mechanical complications, and fluoroscopy time and radiation dose. 146 patients undergoing 285 GJ exchanges met inclusion criteria over the 4-month study period (M:F 82:64). All exchanges were successful with 85 demonstrating a form of mechanical complication (44 coiled, 41 clogged). Of the reported GJ tube specifications, only tube length was significantly associated with mechanical complications (p < 0.001). The presence of mechanical complication was significantly associated with increased radiation exposure and fluoroscopy time (p < 0.0001). Mechanical complications of gastrojejunostomy tubes, such as clogging or coiling, are associated with increased radiation exposure during exchange. Strategies to decrease these complications, including re-siting the gastrostomy tract or placement of a surgical jejunostomy in the event of repeated coiling of a tube should be strongly considered.

Together They Stand: Interpreting Not-At-Issue Content.

Potts unified the account of appositives, parentheticals, expressives, and honorifics as 'Not- At-Issue' (NAI) content, treating them as a natural class semantically in behaving like root (unembedded) structures, typically expressing speaker commitments, and being interpreted independently of At-Issue content. We propose that NAI content expresses a complete speech act distinct from the speech act of the containing utterance. The speech act hypothesis leads us to expect the semantic properties Potts established. We present experimental confirmation of two intuitive observations made by Potts: first that speech act adverbs should be acceptable as NAI content, supporting the speech act hypothesis; and second, that when two speech acts are expressed as successive sentences, the comprehender assumes they are related by some discourse coherence relation, whereas an NAI speech act need not bear a restrictive discourse coherence relation to its containing utterance, though overall sentences containing relevant content are rated more acceptable than those that do not. The speech act hypothesis accounts for these effects, and further accounts for why judgments of syntactic complexity or evaluations of whether or not a statement is true interact with the at-issue status of the material being judged or evaluated.

Early effector cells survive the contraction phase in malaria infection and generate both central and effector memory T cells.

CD4 T cells orchestrate immunity against blood-stage malaria. However, a major challenge in designing vaccines to the disease is poor understanding of the requirements for the generation of protective memory T cells (Tmem) from responding effector T cells (Teff) in chronic parasite infection. In this study, we use a transgenic mouse model with T cells specific for the merozoite surface protein (MSP)-1 of Plasmodium chabaudi to show that activated T cells generate three distinct Teff subsets with progressive activation phenotypes. The earliest observed Teff subsets (CD127(-)CD62L(hi)CD27(+)) are less divided than CD62L(lo) Teff and express memory genes. Intermediate (CD62L(lo)CD27(+)) effector subsets include the most multicytokine-producing T cells, whereas fully activated (CD62L(lo)CD27(-)) late effector cells have a terminal Teff phenotype (PD-1(+), Fas(hi), AnnexinV(+)). We show that although IL-2 promotes expansion, it actually slows terminal effector differentiation. Using adoptive transfer, we show that only early Teff survive the contraction phase and generate the terminal late Teff subsets, whereas in uninfected recipients, they become both central and effector Tmem. Furthermore, we show that progression toward full Teff activation is promoted by increased duration of infection, which in the long-term promotes Tem differentiation. Therefore, we have defined markers of progressive activation of CD4 Teff at the peak of malaria infection, including a subset that survives the contraction phase to make Tmem, and show that Ag and cytokine levels during CD4 T cell expansion influence the proportion of activated cells that can survive contraction and generate memory in malaria infection.

How Competitive Are Crop Markets in Sub-Saharan Africa?

During the structural adjustment era of the 1980s and 1990s, governments across sub-Saharan Africa generally withdrew from crop markets to encourage entry by private traders and foster competition. Since that time, the degree of competition in crop markets has been a central concern of policymakers, donors, and researchers. We review the evidence on that topic by first developing a conceptual framework to guide our analysis, then discussing the findings from four categories of literature. We have two main findings. First, there is a paucity of empirical evidence on this question, which hinders our ability to draw strong conclusions. Second, that point notwithstanding, the evidence that does exist is broadly supportive of the notion that crop markets are competitive. The dominant themes in the literature are that trading profits are highly variable, trader entry and exit rates are high, and price co-movements between markets suggest relatively efficient levels of competitive arbitrage. It is possible that the high costs of entry foster non-competitive conditions at the level of large-scale, long-distance subnational trade, but we find no positive evidence to that effect, only the satisfaction of certain necessary conditions.

Agricultural factor markets in Sub-Saharan Africa: An updated view with formal tests for market failure.

This paper uses the recently collected Living Standard Measurement Study-Integrated Surveys on Agriculture Initiative data sets from five countries in Sub-Saharan Africa to provide a comprehensive overview of factor market participation by agrarian households and to formally test for failures in rural markets. Under complete and competitive markets, households can solve their consumption and production problems separately, so that household factor endowments do not predict input demand. This paper implements a simple, theoretically grounded test of this separation hypothesis, which can be interpreted as a reduced form test of market failure. In all five study countries, the analysis finds strong evidence of factor market failure. Moreover, those failures appear general and structural, not specific to subpopulations defined by gender, geography, human capital, or land quality. However, we show that rural markets are not generally missing in an absolute sense, suggesting that market existence is less of a problem than market function.

Paget-Schroetter syndrome in 21 children: outcomes after multidisciplinary care.

OBJECTIVE: To review the presentation, management, and outcomes of Paget-Schroetter syndrome (PSS) in children and propose a multidisciplinary treatment algorithm involving pediatric and vascular surgery, interventional radiology, and hematology. STUDY DESIGN: Patients with PSS presenting between 2003 and 2013 were reviewed. Demographics, symptoms, therapies, and functional outcomes were noted. Data from early patients informed the development of a multidisciplinary treatment algorithm applied to later patients. RESULTS: Of 21 patients, mean ± SD age was 16 ± 1.6 years and 11 (52%) were male. Of patients with complete presentation data, common symptoms were edema (84%), discoloration (58%), and pain (58%). Thrombophilia workup revealed one heterozygote for factor V Leiden, 2 patients with factor VIII elevation and 1 patient with mildly low antithrombin. The most recent 8 patients were treated according to an algorithm developed by a multidisciplinary working group through experience with the first 13 cases. All patients underwent a venogram, endovascular intervention (including 15 receiving catheter-directed thrombolysis), and operative ipsilateral thoracic outlet decompression (first rib resection, anterior scalenectomy, and venolysis). Postoperative complications included hemothorax (2), pneumothorax (1), and recurrent thrombosis (2). Follow up duration was 12 ± 9.5 months. Symptoms recurred transiently in 1 patient. CONCLUSION: Pediatric patients with PSS can be treated successfully using a multidisciplinary treatment algorithm including anticoagulation, catheter-directed thrombolysis, and operative decompression of the thoracic outlet. Early outcomes are promising.

Fibro-adipose vascular anomaly: clinical-radiologic-pathologic features of a newly delineated disorder of the extremity.

BACKGROUND: The diagnosis and management of vascular anomalies of the extremities can be challenging as these disorders are uncommon and may clinically overlap. The aim of this paper is to describe the clinical, radiologic, and histopathologic features of fibro-adipose vascular anomaly (FAVA), a previously unrecognized disorder of the limb. METHODS: The clinical, imaging, operative, and histopathologic data from patients with a unique intramuscular lesion of the extremities comprising dense fibrofatty tissue and slow-flow vascular malformations were retrospectively reviewed. RESULTS: Sixteen patients diagnosed with FAVA of the extremity (3 male and 13 female individuals) met the clinical, radiologic, and histopathologic inclusion criteria. The age at presentation ranged from the time of birth to 28 years. The locations of the lesions were: calf (n=10), forearm/wrist (n=3), and thigh (n=3). Fourteen patients presented with severe pain. Seven of the patients with calf lesions had limited ankle dorsiflexion. On imaging, the complex intramuscular lesions replaced muscle fibers with fibrofatty overgrowth and phlebectasia (dilation of the veins). The extrafascial component comprised fatty overgrowth, phlebectasia, and an occasional lymphatic malformation. The histopathologic features comprised dense fibrous tissue, fat, and lymphoplasmacytic aggregates within atrophied skeletal muscle. Adipose tissue also infiltrated skeletal muscle at the periphery of the lesion. There were large, irregular, and sometimes excessively muscularized venous channels and smaller, clustered channels. Other findings include organizing thrombi, a lymphatic component, and dense fibrous tissue-encircled nerves. CONCLUSIONS: The constellation of clinical, radiologic, and histopathologic features constitutes a distinct entity comprising fibrofatty infiltration of muscle, unusual phlebectasia with pain, and contracture of the affected extremity. The clinical and radiologic findings permit the diagnosis of FAVA with major therapeutic implications. LEVEL OF EVIDENCE: Level III.

Sonography-guided percutaneous liver biopsies in children.

OBJECTIVE: The purpose of this study was to evaluate the safety and efficacy of sonography-guided percutaneous core needle liver biopsy in infants and children. MATERIALS AND METHODS: We conducted a retrospective analysis of all patients who underwent sonography-guided percutaneous core needle liver biopsies over a 7.5-year period by pediatric interventionalists at a single tertiary center. RESULTS: A total of 597 procedures were performed in 470 patients (270 male and 200 female), with a mean age of 10.5 years (age range, 1 month-21 years). The main indications for biopsies were abnormal liver enzymes (n=129, 21.6%), grading and staging of chronic hepatitis B or C (n=105, 17.6%), evaluation of transplanted liver (n=111, 18.6%), iron overload (n=73, 12.2%), miscellaneous other diffuse parenchymal abnormalities (n=124, 20.7%), and focal hepatic lesions (n=55, 9.2%). The procedures were performed either under sedation (n=311, 52.1%) or general anesthesia (n=286, 47.9%). Diagnostic yield was obtained in 596 biopsies (99.8%) from an average of 2.4 cores in patients with diffuse disease (n=541, 90.6%) and 6.5 cores in patients with focal disease (n=55, 9.2%). Ten patients (1.7%) experienced a major complication, including pneumothorax (n=1, 0.2%), abdominal wall pseudoaneurysm (n=1, 0.2%), and symptomatic bleeding (n=8, 1.3%). Five of these children required transfusion, two were only admitted for observation, and one required surgical evacuation. There were no procedure-related deaths. Minor complications (n=49, 8.2%) included a symptomatic subcapsular hematoma (n=35) and stable small hemoperitoneum (n=9). CONCLUSION: Sonography-guided percutaneous core liver biopsy is a safe and effective procedure in children that has a high diagnostic yield and very low complication rate.

Grammatical Perspective-Taking in Comprehension and Production.

Language use in conversation requires conversation partners to consider each other's points-of-view, or perspectives. A large body of work has explored how conversation partners take into account differences in knowledge states when choosing referring expressions. This paper explores how well findings from perspective-taking in reference generalize to a relatively understudied domain of perspective: the processing of grammatical perspectival expressions like the motion verbs come and go in English. We re-visit findings from perspective-taking in reference that conversation participants are subject to egocentric biases: they are biased towards their own perspectives. Drawing on theoretical proposals for grammatical perspective-taking and prior experimental studies of perspective-taking in reference, we compare two models of grammatical perspective-taking: a serial anchoring-and-adjustment model, and a simultaneous integration model. We test their differing predictions in a series of comprehension and production experiments using the perspectival motion verbs come and go as a case study. While our comprehension studies suggest that listeners reason simultaneously over multiple perspectives, as in the simultaneous integration model, our production findings are more mixed: we find support for only one of the simultaneous integration model's two key predictions. More generally, our findings suggest a role for egocentric bias in production for grammatical perspective-taking as well as when choosing referring expressions.

Person-based prominence guides incremental interpretation: Evidence from obviation in Ojibwe.

Distinctions related to person and animacy have long been known to impact both the grammar and incremental processing in a way that can be described through "prominence" scales. We put the generalizability of these scales to the test by examining the processing effects of a typologically uncommon distinction known as obviation, which is found in Ojibwe, an Indigenous language of North America. Obviation contrasts the single most discourse-salient animate third person (proximate) with other non-salient third persons (obviative). Using a visual world paradigm, we show that obviation influences parsing and interpretation commitments under incremental ambiguity: Proximate nouns are assumed to be the agent of an action, while obviative nouns do not lead to strong incremental commitments. This result parallels previous findings in other languages with distinctions related to animacy and person, supporting a theory where the effect of prominence information in processing is the result of a common set of constraints derived from the alignment of scales related to person, syntactic position, and thematic role.

Individual Differences in Cue Weighting in Sentence Comprehension: An Evaluation Using Approximate Bayesian Computation.

Cue-based retrieval theories of sentence processing assume that syntactic dependencies are resolved through a content-addressable search process. An important recent claim is that in certain dependency types, the retrieval cues are weighted such that one cue dominates. This cue-weighting proposal aims to explain the observed average behavior, but here we show that there is systematic individual-level variation in cue weighting. Using the Lewis and Vasishth cue-based retrieval model, we estimated individual-level parameters for reading speed and cue weighting using 13 published datasets; hierarchical approximate Bayesian computation (ABC) was used to estimate the parameters. The modeling reveals a nuanced picture of cue weighting: we find support for the idea that some participants weight cues differentially, but not all participants do. Only fast readers tend to have the predicted higher weighting for structural cues, suggesting that reading proficiency (approximated here by reading speed) might be associated with cue weighting. A broader achievement of the work is to demonstrate how individual differences can be investigated in computational models of sentence processing without compromising the complexity of the model.