Short pulse of 1080 improves the survival of brown kiwi chicks in an area subjected to long-term stoat trapping

Many mainland populations of kiwi are declining because stoats (Mustela erminea) kill most of their chicks. Stoats are often trapped during conservation programmes, but the long-term effectiveness of trapping has not been measured. During continuous trapping of mammalian predators in the 9800?ha Whangarei Kiwi Sanctuary, the survival of brown kiwi (Apteryx mantelli) chicks declined over time. Following the use of sodium fluoroacetate (1080) to kill rats (Rattus spp.) and possums (Trichosurus vulpecula) and likely secondary poisoning of stoats, chick survival at Riponui increased from 5% to 56%, and the 62% chick survival at Rarewarewa was better than the 20% recorded in a trapped-only area nearby. We suggest that untrappable stoats accumulate in areas subjected to continuous predator trapping. Conservation managers should build into their long-term pest control programmes a periodic pulse of an alternative tool to kill pests that, for whatever reason, actively avoid the primary control tool.     

Higher-level snake phylogeny inferred from mitochondrial DNA sequences of 12S rRNA and 16S rRNA genes

Portions of two mitochondrial genes (12S and 16S ribosomal RNA) were sequenced to determine the phylogenetic relationships among the major clades of snakes. Thirty-six species, representing nearly all extant families, were examined and compared with sequences of a tuatara and three families of lizards. Snakes were found to constitute a monophyletic group (confidence probability [CP] = 96%), with the scolecophidians (blind snakes) as the most basal lineages (CP = 99%). This finding supports the hypothesis that snakes underwent a subterranean period early in their evolution. Caenophidians (advanced snakes), excluding Acrochordus, were found to be monophyletic (CP = 99%). Among the caenophidians, viperids were monophyletic (CP = 98%) and formed the sister group to the elapids plus colubrids (CP = 94%). Within the viperids, two monophyletic groups were identified: true vipers (CP = 98%) and pit vipers plus Azemiops (CP = 99%). The elapids plus Atractaspis formed a monophyletic clade (CP = 99%). Within the paraphyletic Colubridae, the largely Holarctic Colubrinae was found to be a monophyletic assemblage (CP = 98%), and the Xenodontinae was found to be polyphyletic (CP = 91%). Monophyly of the henophidians (primitive snakes) was neither supported nor rejected because of the weak resolution of relationships among those taxa, except for the clustering of Calabaria with a uropeltid, Rhinophis (CP = 94%).      

Does the underprivileged area index work?

The underprivileged area index was developed by Jarman to identify areas with the greatest need for general practitioner services and where general practitioners were under the greatest pressure. We found that in wards that scored the worst on the underprivileged area index the doctor:patient ratios were the highest. We suggest that the index needs to be used with other indicators to identify variations in need in small areas.     

The role of glyceraldehyde 3-phosphate dehydrogenase (GapA-1) in <Emphasis Type="Italic">Neisseria meningitidis</Emphasis> adherence to human cells

Background  

Glyceraldehyde 3-phosphate dehydrogenases (GAPDHs) are cytoplasmic glycolytic enzymes, which although lacking identifiable secretion signals, have also been found localized to the surface of several bacteria (and some eukaryotic organisms); where in some cases they have been shown to contribute to the colonization and invasion of host tissues. Neisseria meningitidis is an obligate human nasopharyngeal commensal which can cause life-threatening infections including septicaemia and meningitis. N. meningitidis has two genes, gapA-1 and gapA-2, encoding GAPDH enzymes. GapA-1 has previously been shown to be up-regulated on bacterial contact with host epithelial cells and is accessible to antibodies on the surface of capsule-permeabilized meningococcal cells. The aims of this study were: 1) to determine whether GapA-1 was expressed across different strains of N. meningitidis; 2) to determine whether GapA-1 surface accessibility to antibodies was dependant on the presence of capsule; 3) to determine whether GapA-1 can influence the interaction of meningococci and host cells, particularly in the key stages of adhesion and invasion.     

Primary antibody-forming cells and secondary B cells are generated from separate precursor cell subpopulations

Two precursor cell subpopulations have been isolated from the spleen cells of nonimmune mice. The major B cell subpopulation binds high levels of the J11D monoclonal antibody and, upon T cell-dependent antigenic stimulation, gives rise to primary antibody-forming cell clones but not secondary B cells. A minority of the 10%-14% of Ia+ precursors that bind low levels of J11D (J11Dlo) also generate antibody-forming cell clones after primary stimulation. However, over 70% of J11Dlo precursors yield no primary antibody-forming cell clones but instead give rise to secondarily responsive B cells. The existence of a distinct precursor cell subpopulation that is responsible for the generation of B cell memory is further evidenced by the distribution of variable region clonotypes among J11Dlo primary precursors, which resembles the clonotype patterns of secondary B cells, and by the accumulation of somatic mutations in their clonal progeny.     

Incidence of psychotic illness in London: comparison of ethnic groups.

OBJECTIVE--To compare annual incidences of psychosis in people from different ethnic groups as defined in the 1991 census. SETTING--Catchment area of district psychiatric hospital. DESIGN--All people aged 16 to 54 years who made contact with a wide range of community and hospital services between 1 July 1991 and 30 June 1992 were screened for psychotic symptoms. Patients with such symptoms were interviewed face to face to collect information on demography, ethnic group, psychiatric history and symptoms, drug use, and how care had been sought. A key informant, usually a close relative, was also interviewed. MAIN OUTCOME MEASURES--Age standardised incidence of schizophrenia and non-affective psychosis according to the ninth edition of the International Classification of Diseases in each ethnic group. RESULTS--Ninety three patients took part, of whom 38 were assigned a certain or very likely diagnosis of schizophrenia (15 in white population, 14 in black, seven in Asian, and two in others). The age standardised annual incidence of schizophrenia was 2.2 (95% confidence interval 1.5 to 2.9) per 10,000 of the population. The incidence ratio for schizophrenia in all ethnic minority groups compared with the white population was 3.6 (1.9 to 7.1); the corresponding figure for non-affective psychosis was 3.7 (2.2 to 6.2). CONCLUSIONS--Raised incidences of schizophrenia were not specific to the African Caribbeans, which suggests that the current focus on schizophrenia in this population is misleading. Members of all ethnic minority groups were more likely to develop a psychosis but not necessarily schizophrenia. The personal and social pressures of belonging to any ethnic minority group in Britain are important determinants in the excess of psychotic disorders found.     

Cutting edge: dysfunctional CD8+ T cells reside in nonlymphoid tissues during chronic Trypanosoma cruzi infection

Chagas disease is caused by persistent Trypanosoma cruzi infection in muscle tissue that ultimately results in chronic inflammation and tissue destruction. It is unclear why T. cruzi is cleared from some tissues but persists in others, despite an active inflammatory response. In this study, we show that the majority of CD8(+) T cells present in muscle tissue express memory and effector cell surface markers but have sharply attenuated effector function compared with their splenic counterparts. The dysfunction of CD8(+) T cells in the muscle tissue suggests a mechanism by which T. cruzi can persist in that location and cause inflammatory damage.