Conversion efficiency of flight power is low, but increases with flight speed in the migratory bat Pipistrellus nathusii.

The efficiency with which flying animals convert metabolic power to mechanical power dictates an individual's flight behaviour and energy requirements. Despite the significance of this parameter, we lack empirical data on conversion efficiency for most species as in vivo measurements are notoriously difficult to obtain. Furthermore, conversion efficiency is often assumed to be constant across flight speeds, even though the components driving flight power are speed-dependent. We show, through direct measurements of metabolic and aerodynamic power, that conversion efficiency in the migratory bat (Pipistrellus nathusii) increases from 7.0 to 10.4% with flight speed. Our findings suggest that peak conversion efficiency in this species occurs near maximum range speed, where the cost of transport is minimized. A meta-analysis of 16 bird and 8 bat species revealed a positive scaling relationship between estimated conversion efficiency and body mass, with no discernible differences between bats and birds. This has profound consequences for modelling flight behaviour as estimates assuming 23% efficiency underestimate metabolic costs for P. nathusii by almost 50% on average (36-62%). Our findings suggest that conversion efficiency may vary around an ecologically relevant optimum speed and provide a crucial baseline for investigating whether this drives variation in conversion efficiency between species.

Prognostic factors of early death in a cohort of 162 adult haemophagocytic syndrome: impact of triggering disease and early treatment with etoposide.

Reactive haemophagocytic syndrome is a life-threatening disease for which factors influencing the outcome remain unclear. We sought to identify determinants of early mortality in patients with reactive haemophagocytic syndrome by conducting a non-interventional retrospective multicentre study in three tertiary care teaching hospitals over a 6-year period. The medical files of 162 patients fulfilling our diagnostic criteria of haemophagocytic syndrome were reviewed. Patients were classified according to 30-d outcome following diagnosis. Thirty-three patients (20·4%) died within 30 d. Clinical features at diagnosis associated with 30-d death in univariate analysis were older age (P = 0·004), underlying lymphoma (P = 0·04), lower platelet count (P = 0·001) and elevated aspartate aminotransferase and lactate dehydrogenase (P = 0·04 both). The use of etoposide as a first-line treatment tended to be associated with a better outcome (P = 0·079). In multivariate analyses, increasing age, decreasing platelet count, underlying lymphoma and no etoposide in the management were associated with a poorer prognosis (P = 0·03, 0·01, 0·003 and 0·04, respectively). These prognostic factors could help to identify those patients more severely affected by reactive haemophagocytic syndrome, who should benefit from aggressive supportive care, combined with specific treatment of the precipitating factor.

The ultrastructure of the rostral gland in soldiers of Verrucositermes tuberosus (Blattodea: Termitidae: Nasutitermitinae).

The soil-feeding habit is an evolutionary novelty found in some advanced groups of termites. The study of such groups is important to revealing interesting adaptations to this way-of-life. The genus Verrucositermes is one such example, characterized by peculiar outgrowths on the head capsule, antennae and maxillary palps, which are not found in any other termite. These structures have been hypothesized to be linked to the presence of a new exocrine organ, the rostral gland, whose structure has remained unexplored. We have thus studied the ultrastructure of the epidermal layer of the head capsule of Verrucositermes tuberosus soldiers. We describe the ultrastructure of the rostral gland, which consists of class 3 secretory cells only. The dominant secretory organelles comprise rough endoplasmic reticulum and Golgi apparatus, which provide secretions delivered to the surface of the head, likely made of peptide-derived components of unclear function. We discuss a possible role of the rostral gland of soldiers as an adaptation to the frequent encounter with soil pathogens during search for new food resources.

[Biclonal or biphenotypic chronic lymphotic leukemia? An answer brought by the treatment]. / Leucémie lymphoïde chronique biclonale ou biphénotypique ? Une réponse par le traitement.

A 51-years-old patient with polyadenopathies presents a non monotypic chronic lymphocytic leukemia (CLL): lymphocytes B CD5+, CD23+, CD22-,CD79b dim, FMC7- express κ (71%) and λ (21%) light chains without coexpression. The caryotype shows two clones with one in evolution. Lymphoid clonality analysis by PCR (polymerase chain reaction) of the heavy and light chains genes of immunoglobulins shows two monoclonal rearrangements for each kind of chains. Lack of lymphoid cells sorting in function of the light chain doesn't allow us to conclude between a biclonal CLL and a biallelic monoclonal CLL. New adenopathies appearance in this patient, one year and a half after the end of his chemotherapy, leads to realisation of a new immunophenotyping: CLL is now monotypic with κ light chains expressed at 95%. In the new caryotype, only one clone is still present: it is the clone in evolution in the first caryotype and which presents additional abnormalities. This evolution allows us to assert the biclonality of the primitive CLL, the two clones evolving differently under treatment. In conclusion, the patient presented a biclonal CLL with one clone responding to treatment and the other one resistant.

Clinically silent indolent T-cell leukemia.

The clinically silent, symptom-free T-cell prolymphocytic leukemia case that we report here confirms the major interest of the analysis of the blood smear as usual care of any emergent lymphocytosis. It also brings out the issue of the monitoring and follow-up of this uncommon presentation.

Cryptic male choice.

Cédric Aumont and David Shuker introduce cryptic male choice, the process by which males bias fertilization during copulation.

The fitness effects of a pale mutant in the aposematic seed bug Lygaeus simulans indicate pleiotropy between warning coloration and life history.

Conspicuous warning colors that signal chemical or other defenses are common in the natural world. For instance, such aposematic warning patterns of red-and-black or yellow-and-black are common among insect taxa, particularly in the order Hemiptera, often forming the basis of Batesian and/or Müllerian mimicry rings. In addition, it has been repeatedly noted that color polymorphisms or mutants that influence pigmentation can show pleiotropy with other behavioral, physiological, or life-history traits. Here, we describe a pale mutant of the seed bug Lygaeus simulans that appeared in our laboratory population in 2012, which differs in color to the wild-type bugs. Through multigenerational experimental crosses between wild-type and pale mutant L. simulans, we first show that the pale phenotype segregates as a single Mendelian locus, with the pale allele being recessive to the wild type. Next, we show (a) that there is a large heterozygous advantage in terms of fecundity, (b) that pale females suffer reduced longevity, and (c) that pale males have increased body length compared to wild-type homozygotes. Our data therefore suggest that the color locus is pleiotropic with a number of life-history traits, opening the door for a more complete genetic analysis of aposematic coloration in this species. In addition, this phenotype will be useful as a visible genetic marker, providing a tool for investigating sperm competition and other post-copulatory drivers of sexual selection in this species.

A composite lymphoma combining a Hodgkin lymphoma and a marginal zone lymphoma transformed into a diffuse large B-cell lymphoma.

Composite lymphoma is defined as the occurrence of two or more distinct lymphoma types in a single anatomic site. We report a case of Richter syndrome with both Hodgkin lymphoma and non-Hodgkin lymphoma in the bone marrow. This diagnostic was suspected because of discrepancies between histological and cytological results.

Epstein-Barr virus viral load in human immunodeficiency virus-positive patients with reactive hemophagocytic syndrome.

Because human immunodeficiency virus (HIV)-infected patients control Epstein-Barr virus (EBV) replication poorly, we hypothesized that reactive hemophagocytic syndrome (HS) in these patients may be associated with poor control of EBV. The files of 314 patients with a suspected diagnosis of HS were retrospectively reviewed. EBV viral load at the time of HS was compared between HIV-positive and -negative patients. A confirmed diagnosis of HS was made in 162 patients [109 males, median age 48 (35-62) years]. Among them, 61 (38%) were HIV positive [median HIV viral load 3.2 (1.6-5.5) log/ml, median CD4 count 94 (28-190)/mm(3)]. The median EBV viral load was significantly higher in HIV-positive than in HIV-negative patients [4.0 (2.9-4.6) vs 2.5 (0-4.2) log/ml, p = 0.002]. It was higher both in patients with hematological malignancy-associated HS [4.0 (2.9-4.4) vs 2.9 (0-4.9) log/ml, p = 0.03] and in patients with infection-associated HS [3.9 (0-4.9) vs 0 (0-4.1) log/ml, p = 0.14]. However, EBV viral load was not significantly higher in HIV-infected patients with confirmed HS than in HIV-infected patients for whom HS was unlikely [4.0 (2.9-4.6) vs 3.9 (2.6-4.1) log/ml, p = 0.48].The high EBV viral load observed in HIV-infected patients with HS may be more likely to reflect the chronic HIV infection than to be the direct trigger of HS.

Early-onset chronic axonal neuropathy, strokes, and hemolysis: inherited CD59 deficiency.

OBJECTIVE: To identify the underlying etiology of 3 patients in a multiplex family with strokes, chronic immune-mediated peripheral neuropathy, and hemolysis. All had onset in infancy. METHODS: We performed genome-wide linkage analysis followed by whole exome sequencing (WES) in the proband, Sanger sequencing, and segregation analysis of putative mutations. In addition, we conducted flow cytometry studies to assess CD59 expression. RESULTS: In a 2-generation-3-affected family with early-onset immune-mediated axonal neuropathy, cerebrovascular event both in the anterior and posterior circulation, and chronic Coombs-negative hemolysis, we detected CD59 deleterious mutation as the underlying cause. Linkage analysis and homozygosity mapping using single nucleotide polymorphism (SNP) microarrays in the family followed by WES in one index case allowed identification of a homozygous missense mutation in the CD59 gene (c.A146T:p.Asp49Val). Sanger sequencing validated the mutation, showing cosegregation with the disease phenotype. Flow cytometry using blood cells in the 3 patients showed a lack of CD59 expression at the cell membrane compared to control and CD55 labeling. CONCLUSION: We added to the knowledge base about inherited CD59 deficiency.

A web-based delphi study for eliciting helpful criteria in the positive diagnosis of hemophagocytic syndrome in adult patients.

The diagnosis of the reactive form of hemophagocytic syndrome in adults remains particularly difficult since none of the clinical or laboratory manifestations are specific. We undertook a study in order to elicit which features constitute helpful criteria for a positive diagnosis. In this Delphi study, the features investigated in the questionnaire and the experts invited to participate in the survey were issued from a bibliographic search. The questionnaire was iteratively proposed to experts via a web-based application with a feedback of the results observed at the preceding Delphi round. Experts were asked to label each investigated criterion in one of the following categories: absolutely required, important, of minor interest, or not assessable in the routine practice environment. A positive consensus was a priori defined as at least 75% answers observed in the categories absolutely required and important. The questionnaire investigated 26 criteria and 24 experts originating from 13 countries participated in the second and final Delphi round. A positive consensus was reached for the nine following criteria: unilineage cytopenia, bicytopenia, pancytopenia, presence of hemophagocytosis pictures on a bone marrow aspirate or on a tissue biopsy, high ferritin level, fever, organomegaly, presence of a predisposing underlying disease, and high level of lactate dehydrogenase. A negative consensus was reached for 13 criteria, and an absence of consensus was observed for 4 criteria. The study constitutes the first initiative to date for defining international guidelines devoted to the positive diagnosis of the reactive form of hemophagocytic syndrome.

Reactive hemophagocytic syndrome in adults: a retrospective analysis of 162 patients.

OBJECTIVES: Current knowledge in reactive hemophagocytic syndrome mainly relies on single-center case series including a relatively small number of patients. We aimed to identify a multicenter large cohort of adult patients with reactive hemophagocytic syndrome and to describe relevant clinical and laboratory features, underlying conditions, and outcome. METHODS: We conducted a multicenter study in 3 tertiary care centers in France over a 6-year period. The medical files of 312 patients with suspected hemophagocytic syndrome were retrospectively reviewed. Patients were classified with a positive, negative, or undetermined diagnosis of hemophagocytic syndrome by experts' consensus. RESULTS: Among the 312 patients fulfilling our inclusion criteria, 162 were classified with positive hemophagocytic syndrome (male, 67%; median age, 48 [35-62] years). Compared with patients without hemophagocytic syndrome, patients with hemophagocytic syndrome more frequently had an underlying immunodepression (45% vs 33%, P = .03) and exhibited higher temperature, ferritin, triglycerides, aspartate transaminase, bilirubin, lactate dehydrogenase, and C-reactive protein, and lower hemoglobin, leukocytes, platelets, and sodium levels. Only 70% of them had hemophagocytosis features on bone marrow aspiration. Hematologic malignancies, especially non-Hodgkin lymphomas, were the main trigger of hemophagocytic syndrome, accounting for 56% of cases. The early mortality rate (ie, within 1 month after diagnosis) was 20%. Patients with hematologic malignancies-associated hemophagocytic syndrome had a poorer early outcome than those with underlying infection. CONCLUSIONS: In this large, multicenter study, hematologic malignancies are the main disease associated with hemophagocytic syndrome in adults. Early mortality is high, and outcome is influenced by the underlying disease.

Development and validation of the HScore, a score for the diagnosis of reactive hemophagocytic syndrome.

OBJECTIVE: Because it has no unique clinical, biologic, or histologic features, reactive hemophagocytic syndrome may be difficult to distinguish from other diseases such as severe sepsis or hematologic malignancies. This study was undertaken to develop and validate a diagnostic score for reactive hemophagocytic syndrome. METHODS: A multicenter retrospective cohort of 312 patients who were judged by experts to have reactive hemophagocytic syndrome (n = 162), were judged by experts to not have reactive hemophagocytic syndrome (n = 104), or in whom the diagnosis of reactive hemophagocytic syndrome was undetermined (n = 46) was used to construct and validate the reactive hemophagocytic syndrome diagnostic score, called the HScore. Ten explanatory variables were evaluated for their association with the diagnosis of hemophagocytic syndrome, and logistic regression was used to calculate the weight of each criterion included in the score. Performance of the score was assessed using developmental and validation data sets. RESULTS: Nine variables (3 clinical [i.e., known underlying immunosuppression, high temperature, organomegaly], 5 biologic [i.e., triglyceride, ferritin, serum glutamic oxaloacetic transaminase, and fibrinogen levels, cytopenia], and 1 cytologic [i.e., hemophagocytosis features on bone marrow aspirate]) were retained in the HScore. The possible number of points assigned to each variable ranged from 0-18 for known underlying immunosuppression to 0-64 for triglyceride level. The median HScore was 230 (interquartile range [IQR] 203-257) for patients with a positive diagnosis of reactive hemophagocytic syndrome and 125 (IQR 91-150) for patients with a negative diagnosis. The probability of having hemophagocytic syndrome ranged from <1% with an HScore of ≤90 to >99% with an HScore of ≥250. CONCLUSION: The HScore can be used to estimate an individual's risk of having reactive hemophagocytic syndrome. This scoring system is freely available online (http://saintantoine.aphp.fr/score/).