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Michael L Wilson

Publications and source records attributed to Michael L Wilson.

13 recordsLinked to original sources
PubMed2005

Comparative rates of violence in chimpanzees and humans.

This paper tests the proposal that chimpanzees (Pan troglodytes) and humans have similar rates of death from intraspecific aggression, whereas chimpanzees have higher rates of non-lethal physical attack (Boehm 1999, Hierarchy in the forest: the evolution of egalitarian behavior. Harvard University Press). First, we assembled data on lethal aggression from long-term studies of nine communities of chimpanzees living in five populations. We calculated rates of death from intraspecific aggression both within and between communities. Variation among communities in mortality rates from aggression was high, and rates of death from intercommunity and intracommunity aggression were not correlated. Estimates for average rates of lethal violence for chimpanzees proved to be similar to average rates for subsistence societies of hunter-gatherers and farmers. Second, we compared rates of non-lethal physical aggression for two populations of chimpanzees and one population of recently settled hunter-gatherers. Chimpanzees had rates of aggression between two and three orders of magnitude higher than humans. These preliminary data support Boehm's hypothesis.

Aggression↗
PubMed2005

Decoration of the aromatic ring of dihydrocodeinone (hydrocodone) and 14-hydroxydihydrocodeinone (oxycodone).

Improved protocols for the preparation of 1-bromodihydrocodeinone (1-bromohydrocodone) and 1-bromo-14-hydroxydihydrocodeinone (1-bromooxycodone) and synthesis of the corresponding 1-chloro and 1-iodo derivatives have been achieved using the corresponding N-halosuccinimides in acidic milieu. The corresponding 1-carboethoxy derivative of 14-hydroxydihydrocodeinone (1-carboethoxyoxycodone) has been prepared by Pd-catalyzed reaction with carbon monoxide in ethanol. The ester was hydrolyzed to the corresponding zwitterionic amino acid.

Acids↗
PubMed2004

Laboratory diagnosis of urinary tract infections in adult patients.

Urinary tract infections (UTIs) are among the most common bacterial infections and account for a significant part of the workload in clinical microbiology laboratories. Enteric bacteria (in particular, Escherichia coli) remain the most frequent cause of UTIs, although the distribution of pathogens that cause UTIs is changing. More important is the increase in resistance to some antimicrobial agents, particularly the resistance to trimethoprim-sulfamethoxazole seen in E. coli. Physicians distinguish UTIs from other diseases that have similar clinical presentations with use of a small number of tests, none of which, if used individually, have adequate sensitivity and specificity. Among the diagnostic tests, urinalysis is useful mainly for excluding bacteriuria. Urine culture may not be necessary as part of the evaluation of outpatients with uncomplicated UTIs, but it is necessary for outpatients who have recurrent UTIs, experience treatment failures, or have complicated UTIs, as well as for inpatients who develop UTIs.

Adult↗
PubMed2004

Collective violence: comparisons between youths and chimpanzees.

Patterns of collective violence found among humans include similarities to those seen among chimpanzees. These include participation predominantly by males, an intense personal and group concern with status, variable subgroup composition, defense of group integrity, inter-group fights that include surprise attacks, and a tendency to avoid mass confrontation. Compared to chimpanzee communities, youth gangs tend to be larger, composed of younger individuals, occupying smaller territories and having a more complex organization. Youth gangs also differ from chimpanzee communities as a result of numerous cultural and environmental influences including complex relations with non-gang society. These relations are governed in important ways by such factors as perceived economic and personal constraints, policing, family structure, and levels of poverty, crime, and racism. Nevertheless, the concepts that sociologists use to account for collective violence in youth gangs are somewhat similar to those applied by anthropologists and biologists to chimpanzees. Thus in both cases collective violence is considered to emerge partly because males are highly motivated to gain personal status, which they do by physical violence. In the case of youth gangs, the reasons for the prevalence of physical violence in status competition compared to non-gang society are clearly context-specific, both culturally and historically. By contrast, among chimpanzees the use of physical violence to settle status competition is universal (in the wild and captivity). The use of physical violence in individual status competition therefore has different sources in youth gangs and chimpanzees. Regardless of its origin, however, its combination with an intense concern for status can explain: (1) why individual males form alliances among each other; and hence (2) how such alliances generate social power, closed groups, and a capacity for defense of territory or pre-emptive attacks on rivals. This comparison suggests that the use of physical violence to resolve individual status competition is an important predictor of collective violence at the gang level. We therefore view the similarities in aggression between humans and chimpanzees that we review here as being adaptive responses to local conditions, predicated on an inherent male concern for social status.

Adolescent↗
PubMed2003

Conventional and molecular epidemiology of trimethoprim-sulfamethoxazole resistance among urinary Escherichia coli isolates.

BACKGROUND: Antibiotic resistance is increasing in Escherichia coli, the most common cause of urinary tract infections, but its epidemiology has not been well described. We evaluated the epidemiology of trimethoprim-sulfamethoxazole-resistant E. coli in a large, public health care system in Denver, Colorado. METHODS: Outpatients with E. coli urinary tract infections during the first 6 months of 1998 were evaluated retrospectively. A prospective study was then performed to confirm the rate of trimethoprim-sulfamethoxazole resistance. We used several strain-typing methods (pulsed-field gel electrophoresis, ribotyping, serotyping) to evaluate the molecular epidemiology of the resistance. RESULTS: The rate of trimethoprim-sulfamethoxazole resistance was similar in the retrospective (24% [161/681]) and prospective (23% [30/130]) phases of the study (P = 0.89). Almost all trimethoprim-sulfamethoxazole-resistant strains (98%) were resistant to at least one other antibiotic. Risk factors for infection with a resistant strain included age < or =3 years, Hispanic ethnicity, recent travel outside the United States, and a prior urinary tract infection. However, rates of resistance were >15% among nearly all of the subgroups. Most strains had high-level resistance (>1000 microg/mL) to trimethoprim-sulfamethoxazole. Of the 23 resistant isolates evaluated, 10 (43%) belonged to the clone A group. There was no correlation between conventional epidemiologic characteristics and the molecular mechanism of resistance or strain type. CONCLUSION: Resistance to trimethoprim-sulfamethoxazole among E. coli isolates among patients in a Denver public health care system is common, with high rates of resistance even among patients without risk factors.

Adolescent↗
PubMed2003

Infectious diseases detected at autopsy at an urban public hospital, 1996-2001.

Previous studies have demonstrated significant discrepancy rates between clinical and autopsy diagnoses. However, infectious diseases have not received emphasis in these studies. We conducted a study to determine whether the clinical and autopsy diagnoses of infectious diseases are concordant or discrepant and to determine discrepancy rates. Retrospective reviews of the records of 276 patients (adults, 182; fetuses and neonates, 94) who underwent autopsy during the years 1996 through 2001 were performed. Comparison of clinical and autopsy diagnoses was performed using the Goldman classification scheme. Of 182 adult patients, 137 (75.3%) had an infectious disease at autopsy. In 59 (43.1%) of 137 patients, the infectious disease diagnoses were unknown clinically. Of 94 fetuses and neonates, 45 (48%) had an infectious disease at autopsy. In 26 (58%) of 45 patients, the infectious disease diagnoses were unknown before death. There are substantial discrepancies between clinical and autopsy diagnoses of infectious diseases. In adults, acute bronchopneumonia is the infectious disease most often missed clinically; in fetuses and neonates, it is acute chorioamnionitis.

Adult↗
PubMed2002

Chimpanzees and the mathematics of battle.

Recent experiments have demonstrated the importance of numerical assessment in animal contests. Nevertheless, few attempts have been made to model explicitly the relationship between the relative number of combatants on each side and the costs and benefits of entering a contest. One framework that may be especially suitable for making such explicit predictions is Lanchester's theory of combat, which has proved useful for understanding combat strategies in humans and several species of ants. We show, with data from a recent series of playback experiments, that a model derived from Lanchester's 'square law' predicts willingness to enter intergroup contests in wild chimpanzees (Pan troglodytes). Furthermore, the model predicts that, in contests with multiple individuals on each side, chimpanzees in this population should be willing to enter a contest only if they outnumber the opposing side by a factor of 1.5. We evaluate these results for intergroup encounters in chimpanzees and also discuss potential applications of Lanchester's square and linear laws for understanding combat strategies in other species.

Aggression↗
PubMed2002

Appropriate use of clinical microbiology tests.

Laboratory medicine lacks the tools necessary to define appropriate test use; nonetheless, existing laboratory test characteristics, although inadequate, provide a common starting point for developing definitions of appropriate test use. As Lundberg [1], Szczepura [15], and van Walraven and Naylor [2] have emphasized, developing a process for defining appropriate laboratory use should receive a high priority. There is a particular need to develop methods for standardizing studies [59]. Laboratory medicine does not, however, lack the tools necessary to change test use. Although past interventions were largely ineffective, there is growing evidence that test use can be changed by use of a variety of approaches. By using the existing tools there is much that can be done to change inappropriate test use, such as minimizing redundant testing or the use of tests that have no clinical relevance. The real opportunities will come when there are scientifically and medically sound definitions of appropriate test use that can be used to change test use and improve patient care in a cost-effective way.

Clinical Laboratory Techniques↗