2,455 publications from this institution
Enteric fever is the only bacterial infection of humans for which bone marrow examination is routinely recommended. A prospective study of the concentrations of bacteria in the bone marrow and their relationship to clinical features was conducted with 120 Vietnamese patients with suspected enteric fever, of whom 89 had confirmed typhoid fever. Ninety-three percent of the Salmonella enterica serovar Typhi samples isolated were resistant to ampicillin, chloramphenicol, and co-trimoxazole. For 81 patients with uncomplicated typhoid and satisfactory bone marrow aspirates, the number of serovar Typhi CFU in bone marrow aspirates was a median value of 9 (interquartile range [IQR], 1 to 85; range, 0.1 to 1,580) compared to 0.3 (IQR, 0.1 to 10; range, 0.1 to 399) CFU/ml in simultaneously sampled blood. The ratio of individual blood counts to bone marrow counts was 10 (IQR, 2.3 to 97.5). The number of bacteria in blood but not bone marrow was correlated inversely with the duration of preceding fever. Thus, with increasing duration of illness the ratio of bone marrow-to-blood bacterial concentrations increased; the median ratio was 4.8 (IQR, 1 to 27.5) during the first week compared with 158 (IQR, 60 to 397) during the third week. After lysing the host cells, the median ratio of viable bone marrow to blood increased, reflecting the higher concentration of intracellular serovar Typhi in the bone marrow. Effective antibiotic pretreatment had a significantly greater effect in reducing blood counts compared to bone marrow counts ( P < 0.001). Thus, bacteria in the bone marrow of typhoid patients are less affected by antibiotic treatment than bacteria in the blood. The numbers of bacteria in bone marrow correlated negatively with the white blood cell ( R = −0.3, P = 0.006) and platelet counts ( R = −0.32, P = 0.01) and positively with fever clearance time after treatment ( R = 0.4, P < 0.001). The bacterial load in bone marrow therefore may reflect the clinical course of the infection, and high levels may suppress neutrophil proliferation.
An estimated 1.1 billion people residing in the tropical world are at high risk for malaria. In 2016, there were an estimated 216 million cases of malaria worldwide causing 445,000 deaths. Africa accounted for 90% of the cases and 91% of deaths; around 70% of the deaths were in children aged less than 5 years. Malaria is transmitted by the female anopheles mosquito and six species of Plasmodium commonly cause malaria in humans: P. falciparum, P. vivax, P. ovale (two species), P. malariae, and P. knowlesi. P. falciparum, the most pathogenic species accounts for 99% of malaria deaths. First line treatment of uncomplicated falciparum malaria is with artemisinin combination therapies (ACTs).
Individual differences in growth and size of vertebrates often represent adaptive, plastic responses to contrasts in ecological conditions. Recent studies show that vertebrates can also modify their growth and size in an adaptive fashion in response to fine-grain changes in social conditions (which we refer to as strategic growth). Here, we review experimental evidence for strategic growth in social vertebrates. We describe a set of conditions under which strategic growth commonly occurs, and highlight potential examples of convergent evolution of strategic growth across the tree of life. This synthesis has implications for the way we think about organismal growth and size, because it underscores that the size of individuals can often be fine-tuned to their social environment.
No abstract is provided for this article.
Background Surgery for craniosynostosis is associated with the potential for significant blood loss. Multiple technologies have been introduced to reduce the volume of blood transfused. These are preoperative autologous donation; preoperative erythropoietin; intraoperative cell salvage (CS); acute normovolemic hemodilution; antifibrinolytic drugs such as tranexamic acid, ε-aminocaproic acid, and aprotinin; fibrin sealants or fibrin glue; and postoperative drain reinfusion. Methods All comparative studies with a treatment group and a control group were considered. There was a range of different study types from randomized controlled trials to case series with historic controls. These were intervention versus no intervention or a comparison of 2 interventions. Studies were identified by searching Cochrane CENTRAL, MEDLINE, and EMBASE; manufacturer's Web sites; and bibliographies of relevant published articles. The primary outcome measures were the number of allogeneic blood donor exposures, the volume of allogeneic blood transfused, and the postoperative hemoglobin or hematocrit levels. Results A total of 696 studies were identified. After removal of duplicates and after exclusion criteria were applied, there were 18 studies to be included. Fourteen were case series with controls and 4 were randomized controlled trials. Conclusions The production of high-quality evidence on the interventions to minimize blood loss and transfusion in children undergoing surgery for craniosynostosis is difficult. Most of the literature is nonrandomized and noncomparative. Several areas remain unaddressed. Erythropoietin and tranexamic acid are comparatively well studied; CS, acute normovolemic hemodilution, and aprotinin are less so. There is only 1 comparative study on the use of fibrin glue and drain reinfusion, with no studies on preoperative autologous donation and [Latin Small Letter Open E]-aminocaproic acid. Tranexamic acid is clinically effective in reducing allogeneic blood transfusion. There is some evidence that CS and erythropoietin may be clinically effective. None of the interventions studied are shown to be cost-effective because of lack of evidence.
An abstract is not available for this content so a preview has been provided. Please use the Get access link above for information on how to access this content.
The ranging behaviour of one troop of red colobus in the Gombe National Park is described. The troop moved about its range in a semi-regular fashion, spending much more time in some areas than in others. The distribution of its time was closely correlated with the joint distribution of the three tree species on which the animals fed most. At the time of year when they fed most on shoots and flowers (as opposed to mature leaves) the animals moved furthest each day, visited the greatest number of different areas, distributed their time most evenly across the range and moved around it in the shortest period.
