Proof of concept for a novel insecticide bioassay based on sugar feeding by adult Aedes aegypti (Stegomyia aegypti).

Aedes aegypti L. (Stegomyia aegypti) (Diptera: Culicidae) is the principal vector of dengue and yellow fever viruses in tropical and subtropical regions of the world. Disease management is largely based on mosquito control achieved by insecticides applied to interior resting surfaces and through space sprays. Population monitoring to detect insecticide resistance is a significant component of integrated disease management programmes. We developed a bioassay method for assessing insecticide susceptibility based on the feeding activity of mosquitoes on plant sugars. Our prototype sugar-insecticide feeding bioassay system was composed of inexpensive, disposable components, contained minimal volumes of insecticide, and was compact and highly transportable. Individual mosquitoes were assayed in a plastic cup that contained a sucrose-permethrin solution. Trypan blue dye was added to create a visual marker in the mosquito's abdomen for ingested sucrose-permethrin solution. Blue faecal spots provided further evidence of solution ingestion. With the sugar-insecticide feeding bioassay, the permethrin susceptibility of Ae. aegypti females from two field-collected strains was characterized by probit analysis of dosage-response data. The field strains were also tested by forced contact of females with permethrin residues on filter paper. Dosage-response patterns were similar, indicating that the sugar-insecticide feeding bioassay had appropriately characterized the permethrin susceptibility of the two strains.

Virus-free adenocarcinoma of the frog (summer phase tumor) transcribes Lucké tumor herpesvirus-specific RNA.

[(3)H]RNA isolated from "virus-free," summer phase, renal adenocarcinomas of Rana pipiens labeled with [(3)H]uridine hybridizes with DNA of herpesvirus particles isolated from the winter phase Lucké tumor. Transcription of the herpesvirus genome in virus-free tumors provides additional evidence for the viral etiology of this tumor.

Assessing the potential of upper respiratory tract point-of-care testing: a systematic review of the prognostic significance of upper respiratory tract microbes.

OBJECTIVES: Microbial point-of-care testing (POCT) has potential to revolutionize clinical care. Understanding the prognostic value of microbes identified from the upper respiratory tract (a convenient sampling site) is a necessary first step to understand potential for upper respiratory tract POCTs in assisting antimicrobial treatment decisions for respiratory infections (RTIs). The aim was to investigate the relationship between upper respiratory tract microbial detection and disease prognosis, including effects of antimicrobial use. METHODS: Data sources were the MEDLINE and Embase databases. Study eligibility criteria consisted of quantitative studies reporting microbiological and prognostic data from patients of all age groups presenting with RTI. Patients presenting to healthcare or research settings with RTI participated. Interventions included upper respiratory tract swab. The methods used were systematic review and meta-analysis. RESULTS: Searches identified 5156 articles, of which 754 were duplicates and 4258 excluded on title or abstract. A total of 144 full texts were screened; 21 articles were retained. Studies reported data for 15 microbes and 26 prognostic measures (390 potential associations). One hundred and seven (27%) associations were investigated statistically, of which 38 (36%) were significant. Most studies reported only prognostic value of test positive results. Meta-analyses suggested hospitalization duration was longer for patients with respiratory syncytial virus than adenovirus and influenza, but significant heterogeneity was observed between studies. CONCLUSIONS: A quarter of potential prognostic associations have been investigated. Of these, a third were significant, suggesting considerable potential for POCT. Future research should investigate prognostic value of positive and negative tests, and interactions between test results, use of antimicrobials and microbial resistance.

Interventions to improve risk communication in clinical genetics: systematic review.

OBJECTIVE: Effective risk communication may enable clients to participate effectively in decision-making about their health and health care. A systematic review of existing literature on risk communication in genetics, and its effects on key outcomes for clients, was undertaken. METHOD: Systematic searching of six electronic databases and data extraction from included studies; narrative synthesis of results. RESULTS: Twenty-eight studies were included, principally from cancer genetics. Sixteen communication interventions have been evaluated, generally showing improvements in cognitive outcomes for users, such as knowledge, understanding and risk perception, and without adverse effects on anxiety, cancer-related worry and depression. However, often it was the supportive or emotional elements of counselling that provided benefits to users, rather than the informational or educational elements. Similar results were found in 12 further studies of decision aids which also appear to achieve shorter consultations that can focus more on the supportive elements of counselling. CONCLUSION: For both communication models and decision aids, the supportive or emotional elements of counselling provided more benefits to users than the informational or educational elements. PRACTICE IMPLICATIONS: Debate is required on how to strike a balance between the medical model, its agenda and perceived requirements to disclose or discuss a range of issues and the sometimes competing goals of addressing users' concerns, needs for support, issues of loss and relationship problems.

Cognitive changes in alcohol-induced psychotic disorder.

AIMS: This study aimed to explore the neuro-cognitive deficits of alcohol-induced psychotic disorder as compared to the cognitive deficits of uncomplicated alcohol dependence. METHODS: Participants were recruited from the acute psychiatric admission wards of the Department of Psychiatry, University of Stellenbosch and Stikland and Tygerberg Academic Hospitals in the Western-Cape, South Africa. Participants who met DSM IV TR criteria (American Psychiatric Association. Diagnostic and statistical manual of mental disorders. American Psychiatric Association, Washington, DC, 2000) for Alcohol Dependence and for alcohol-induced psychotic disorder, respectively, were included. Participants who met criteria for another current DSM IV TR Axis I disorder were excluded. A structured interview was done prior to neuropsychological assessment to ascertain current mental state and to obtain relevant demographic detail and history. Neuropsychological assessments were performed and supervised by clinical psychologists at either Tygerberg or Stikland Hospital. RESULTS: The groups were matched demographically with similar period of abstinence prior to assessment. The alcohol-induced psychotic disorder group experienced first psychotic symptoms at age 35. The results reflected statistically significant differences on tasks measuring immediate memory; recall upon delay; exaggeration of memory difficulty and abstract thinking. CONCLUSION: This study concurs with earlier literature that some cognitive deficits are greater in alcohol-induced psychotic disorder compared to uncomplicated alcohol dependence.

The assay of pyruvate kinase activity in gastric mucosa.

Pyruvate kinase activity in gastric mucosal supernatant preparations shows large responses to exogenous effectors. At pH 7.5, fructose 1,6-diphosphate can cause large stimulations in activity. Alanine inhibits the reaction but this effect is partially reversed by fructose 1,6-diphosphate. In the absence of these compounds, 4.0-5.0 mM phosphoenolpyruvate (PEP) is required to generate maximal activity in the assay system used. Electrophoresis reveals an isoenzyme pattern containing only one form of pyruvate kinase, an M isoenzyme, in both fundic and antral mucosa. The pyruvate kinase of gastric mucosa thus resembles the M-type enzymes of leucocytes and liver. Measurements of activity at both 1.0 mM PEP and 4.0--5.0 mM PEP, with and without additions of fructose 1,6-diphosphate, are recommended for the reliable estimation of pyruvate kinase activity in this tissue.

Oncogenes: their presence and significance in squamous cell cancer of the head and neck.

DNA extracted from squamous cell carcinomas of the larynx and tongue has been shown to contain cellular transforming genes characterized by their ability to transform mouse fibroblasts into malignant foci of cells which, when subsequently cloned and grown to volume, have been found to contain human DNA sequences. This DNA has been serially passaged through subsequent populations of NIH/3T3 mouse fibroblasts. Higher malignant transformation efficiencies have been observed and reported with serial passage. Of greater significance is the repeated identification of oncogenes of identical characteristics on electrophoretic radioisotope analysis.

Oncogenes: preliminary studies in head and neck cancer.

DNA has been extracted from squamous cell carcinomas of the larynx, base of tongue, and nasopharynx. These tumors were excised from patients at the St. Louis University Medical Center and processed at the Institute for Molecular Virology of the St. Louis University Medical Center. NIH/3T3 cells were transfected with the DNAs from these cancers. Malignant, transformed foci of NIH/3T3 cells have been observed. These foci have been cloned and grown in quantity. The cloned foci have been injected into nude mice with the production of highly malignant sarcomas. DNA extracted from these sarcomas has shown homology with human DNA on hybridization analyses of both nasopharynx and tongue cancer. Further hybridization studies are being conducted on the larynx cancer-induced sarcomas and on the DNAs taken from the original transformed foci of NIH/3T3 cells transfected with squamous cell cancers of the larynx, nasopharynx, and tongue base. Our preliminary results indicating the presence of human sequences in the mouse sarcomas support the hypothesis that human cellular transforming gene(s) may be present in the DNA isolated from the head and neck cancers. Additional studies will include repetitive retransfection of NIH/3T3 cells, molecular cloning of putative oncogenes, and DNA sequence analysis of the cloned oncogenes. It is hoped that identification of putative oncogene sequences will result in the identification of the proteins coded for by the specific nucleotide sequences responsible for malignant cellular transformation by DNA extracted from head and neck tumors.

Oncogenes in laryngeal cancer: serial passage of transformed cellular DNA.

DNA originally extracted from squamous cell cancer of the larynx has been serially passaged through transformed populations of NIH/3T3 mouse fibroblasts. The transformed foci were then harvested, cloned to volume, and incubated with a fresh population of NIH/3T3 cells in a second passage. Transforming efficiencies were enhanced by serial passage. In addition, Southern Blot analysis of the transformed foci revealed hybridization between transformant DNA and human probe DNA from the Alu family of conserved human DNA sequences. In the first passage this hybridization took the form of diffuse homology throughout the entire molecular weight distribution. The second-passage DNA showed "narrow bands" indicating the possibility that an oncogene has been identified in laryngeal cancer and that serial passage has eliminated contaminating human sequences. Repetitive transfection in third- and fourth-passage studies is now being completed.

Survival after extended resection for locally advanced carcinomas of the colon and rectum.

Two hundred and fifty five patients were treated surgically for adenocarcinoma of the colon or rectum on the Surgical Unit at Westminster Hospital in the years 1962-78. After 13 patients had been excluded on the grounds of inadequate data, 57 of the remaining 242 had tumours which, at laparotomy, were firmly adherent to neighbouring organs or the abdominal wall. These 'locally advanced' tumours were treated by an extended en-bloc resection of the tumour and neighbouring organs. The operative mortality after extended resections was higher than after standard resections, but subsequent survival did not differ significantly from survival after standard excisions for tumours of the same Dukes' stage. Histological examination of the neighbouring organs included in the extended resections confirmed direct tumour spread in only 33%.

Follow-up of postsecondary-age rural learning disabled graduates and dropouts.

This article reports the dropout rates, basic skills competency levels, and employment status of a group of semi-rural learning disabled postsecondary-age youth and a control group of nonlearning disabled same-age peers. Findings indicated significantly higher dropout rates and significantly lower basic skills competency levels among learning disabled youth. Learning disabled graduates and dropouts were not different in how they fared in the employment market for the group, nor were they different compared to peers. Educational implications of these findings and future suggestions for follow-up research are discussed.

Accuracy of prediction of walking for young stroke patients by use of the FIM.

BACKGROUND AND PURPOSE: Clinical prediction of walking outcome after a stroke is essential for effective discharge planning. However, its accuracy has hardly been explored. This study took place in a regional unit admitting patients with complex neurological disabilities for specialist inpatient rehabilitation. The aim was to compare predicted outcome (goal score) with achieved outcome (discharge score) on the seven-point locomotion subscale of the Functional Independence Measure (FIM), to evaluate its precision and identify factors influencing accuracy. METHOD: Admission, goal and discharge scores were analysed retrospectively for 141 subjects (90 M; 51 F) admitted consecutively to the Unit with median age 54 years (range 15-68 years) with median length of stay 13.6 weeks (range 3-35 weeks). RESULTS: Ninety subjects (64%) gained from two to six points; 50 subjects (35%) gained one point or showed no change. One patient deteriorated by two points. Excluding patients admitted with the highest score (FIM level 7), the overall level of agreement between predicted and discharge scores was moderate (weighted kappa 0.47). Prediction was accurate to +/- 1 point in 113 subjects (80%). Overprediction by > or = 2 points occurred in 16 subjects (11%) and underprediction by > or = 2 points in 12 subjects (9%). Analysis of the most-disabled cohort, admitted with FIM levels 1 or 2 scores, revealed a higher sensitivity for predicting 'independence' (FIM levels 5-7) (78%) than 'dependence' (FIM levels 1-4) (65%). Accuracy was not affected by age, gender or side of stroke. Inaccurate predictions were associated with lower admission FIM level scores (p = -0.26; p = 0.002) and a greater length of stay (p = 0.36; p < 0.001). Subjects with quadriplegia were more likely to have inaccurate outcome predictions made than those with hemiplegia (p = 0.025) and those with neglect were more likely to have inaccurate outcome predictions made than those without neglect (p = 0.017). CONCLUSION: Further investigation into clinical prediction and the variables which confound accuracy is needed for effective planning.

The effects of atropine and adrenergic antagonists on behavioral arousal in rats.

Two experiments investigated the mechanism for changes in measures of behavioral arousal inhibition in rats following administration of atropine. In Experiment 1, 40-day-old rats were given administrations of atropine sulfate, the alpha-, beta-adrenergic blocker labetalol, or both. The drugs, either alone or in combination, increased transport response intensity, whereas both together increased dorsal immobility durations. In Experiment 2, rats were given atropine, the beta-adrenergic antagonist propranolol, the alpha-adrenergic antagonist phentolamine, or a combination of two of the drugs. Propranolol blocked atropine-induced increases in transport response, and phentolamine was without effect. Phentolamine, when combined with atropine, increased dorsal immobility durations. Results are discussed with respect to aspects common to both transport response and dorsal immobility.

Improving paediatric diabetes care.

The authors review the management of paediatric patients in diabetic ketoacidosis. Paying particular attention to the pathophysiology of the illness and nursing documentation, they have developed a new diabetic ketoacidosis flow chart to improve nursing care.

A sacrifice for others? Ethical dilemmas surrounding the UK randomised trial for the management of screen-detected ductal carcinoma in situ of the breast.

Asymptomatic ductal carcinoma in situ (DCIS) is a noninvasive breast lesion for which an effective treatment has yet to be ascertained. Women diagnosed with DCIS are therefore given the choice of either participating in a trial or choosing their own treatment. This raises a series of ethical dilemmas for both the patient and community health team.

Regulatory T cells expressing granzyme B play a critical role in controlling lung inflammation during acute viral infection.

The inflammatory response to lung infections must be tightly regulated, enabling pathogen elimination while maintaining crucial gas exchange. Using recently described "depletion of regulatory T cell" (DEREG) mice, we found that selective depletion of regulatory T cells (Tregs) during acute respiratory syncytial virus (RSV) infection enhanced viral clearance but increased weight loss, local cytokine and chemokine release, and T-cell activation and cellular influx into the lungs. Conversely, inflammation was decreased when Treg numbers and activity were boosted using interleukin-2 immune complexes. Unexpectedly, lung (but not draining lymph node) Tregs from RSV-infected mice expressed granzyme B (GzmB), and bone marrow chimeric mice with selective loss of GzmB in the Treg compartment displayed markedly enhanced cellular infiltration into the lung after infection. A crucial role for GzmB-expressing Tregs has not hitherto been described in the lung or during acute infections, but may explain the inability of children with perforin/GzmB defects to regulate immune responses to infection. The effects of RSV infection in mice with defective immune regulation closely parallel the observed effects of RSV in children with bronchiolitis, suggesting that the pathogenesis of bronchiolitis may involve an inability to regulate virus-induced inflammation.

Hypervigilance for fear after basolateral amygdala damage in humans.

Recent rodent research has shown that the basolateral amygdala (BLA) inhibits unconditioned, or innate, fear. It is, however, unknown whether the BLA acts in similar ways in humans. In a group of five subjects with a rare genetic syndrome, that is, Urbach-Wiethe disease (UWD), we used a combination of structural and functional neuroimaging, and established focal, bilateral BLA damage, while other amygdala sub-regions are functionally intact. We tested the translational hypothesis that these BLA-damaged UWD-subjects are hypervigilant to facial expressions of fear, which are prototypical innate threat cues in humans. Our data indeed repeatedly confirm fear hypervigilance in these UWD subjects. They show hypervigilant responses to unconsciously presented fearful faces in a modified Stroop task. They attend longer to the eyes of dynamically displayed fearful faces in an eye-tracked emotion recognition task, and in that task recognize facial fear significantly better than control subjects. These findings provide the first direct evidence in humans in support of an inhibitory function of the BLA on the brain's threat vigilance system, which has important implications for the understanding of the amygdala's role in the disorders of fear and anxiety.