Infrasound detection of approaching lahars.

Infrasound may be used to detect the approach of hazardous volcanic mudflows, known as lahars, tens of minutes before their flow fronts arrive. We have analyzed signals from more than 20 secondary lahars caused by precipitation events at Fuego Volcano during Guatemala's rainy season in May through October of 2022. We are able to quantify the capabilities of infrasound monitoring through comparison with seismic data, time lapse camera imagery, and high-resolution video of a well-recorded event on August 17. We determine that infrasound sensors, deployed adjacent to the lahar path and in small-aperture (10 s of meters) arrays, are particularly sensitive to remote detection of lahars, including small-sized events, at distances of at least 5 km. At Fuego Volcano these detections could be used to provide timely alerts of up to 30 min before lahars arrive at a downstream monitoring site, such as in the frequently impacted Ceniza drainage. We propose that continuous infrasound monitoring, from locations adjacent to a drainage, may complement seismic monitoring and serve as a valuable tool to help identify approaching hazards. On the other hand, infrasound arrays located a kilometer or more from the lahar path can be effectively used to track a lahar's progression.

Heterogeneity of quality of life in the later stages of first-episode psychosis recovery.

PURPOSE: First-episode psychosis (FEP) is characterised by wide heterogeneity in terms of symptom presentation and illness course. However, the heterogeneity of quality of life (QoL) in FEP is not well understood. We investigated whether subgroups can be identified using participants' responses on four QoL domains (physical health, psychological, social relationships, and environmental) 18-months into the recovery phase of FEP. We then examined the discriminant validity of these subgroups with respect to clinical, cognitive, and functioning features of FEP. METHOD: Demographic and clinical characteristics, QoL, cognition, and functioning were assessed in 100 people with FEP at the 18-month follow-up of a randomised controlled trial of Individual Placement Support, which aims to facilitate vocational recovery. QoL was measured using the World Health Organisation's QoL-BRIEF. A two-stage clustering approach using Ward's method and Squared Euclidean Distance with a k-means confirmation was conducted. Multinomial logistic regressions were used to establish external validity. RESULTS: Three QoL subgroups emerged: a 'good' subgroup with relatively high QoL across all domains (31%), an 'intermediate' subgroup with relatively low psychological QoL (48%) and a 'poor' subgroup with markedly low social relationship QoL (21%). Negative symptoms, depressive symptoms, social/occupational functioning, and social inclusion at follow-up predicted subgroup membership. Sensitivity analysis found similar results. CONCLUSION: Although some individuals with FEP have QoL comparable to individuals without mental ill health, QoL can remain concerningly low despite treatment efforts. Future research on interventions that target factors associated with poor QoL, such as low social inclusion, is required to counteract prolonged poor QoL in FEP.

Quality of life in first episode psychosis: a cluster analytic approach.

PURPOSE: Quality of life is increasingly recognised as an important outcome for young people with first episode psychosis (FEP). The first aim was to determine whether distinct homogenous subgroups of young people with FEP could be delineated based on profiles on quality of life domains (Physical Health, Psychological, Social relationships and Environmental). The second aim was to examine the discriminant validity of these subgroups with respect to demographic, functioning and clinical features of FEP. METHOD: Quality of life, demographic characteristics, clinical characteristics, cognition and functioning were assessed in 145 people with FEP. Cluster analysis using Ward's methods and Squared Euclidean Distance with a k-means verification were employed to identify subgroups with homogenous quality of life profiles. The clusters were externally validated using multinomial logistic regressions. RESULTS: Three distinct quality of life profiles were identified: one with good quality of life across all domains (30%), one with poor quality of life particularly in Psychological and Social relationships domains (28%), and one 'intermediate' group with comparatively low Psychological quality of life (42%). Depression, semantic verbal fluency, social inclusion and social/occupational functioning showed associations with group membership. CONCLUSION: Our results suggest the potential of maintaining relatively good quality of life despite the experience of FEP. Future research on interventions to improve quality of life may consider the potential of addressing depression, social inclusion and social/occupational functioning.

End-of-life decision-making in individuals with locked-in syndrome in the acute period after brainstem stroke.

Locked-in syndrome (LIS) is commonly associated with a poor prognosis, particularly if the aetiology is stroke. Dealing with individuals with LIS and a poor prognosis raises the issue of introducing end-of-life discussions with the patient and/or family in the acute period of the illness. Existing literature regarding LIS provides little guidance about end-of-life decision-making in the acute management phase. We aim to provide some guidance for clinicians holding end-of-life discussions in the acute management period. We report two cases of relatively young individuals with LIS secondary to brainstem stroke. Both cases had a very poor prognosis and end-of-life discussions were commenced by the treating team in the acute phase. Despite the severity of their conditions, in neither case were end-of-life discussions well tolerated by the family in the weeks following admission. We suggest that LIS patients and their families, who have chosen to persist with full medical management after diagnosis of LIS, should be provided with sufficient time to adjust to the catastrophic changes that have occurred before further end-of-life discussions are pursued. Education and support are likely to be highly beneficial in the acute period post stroke as they allow the patient and family to develop a realistic understanding of the likely outcomes of their decisions.

A carbon dioxide, heat and chemical lure trap for the bedbug, Cimex lectularius.

A trap for the collection of bedbugs, Cimex lectularius Linnaeus (Hemiptera: Cimicidae), is described. The trap was baited with CO2 (50-400 mL/min), heat (37.2-42.2 degrees C) and a chemical lure comprised of 33.0 microg proprionic acid, 0.33 microg butyric acid, 0.33 microg valeric acid, 100 microg octenol and 100 microg L-lactic acid, impregnated into a gel. Laboratory studies, conducted in a square arena measuring 183 cm on each side, showed that traps with and without baits captured adult bedbugs, but traps with CO2 emissions of 50-400 mL/min caught significantly (P < 0.05) more bedbugs than traps without CO2. In an infested unoccupied apartment, traps with heat and with or without the chemical lure were tested without CO2 on 29 trap-days and with CO2 on 9 trap-days. The numbers of bedbugs captured were 656 and 5898 in traps without and with CO2, respectively. The numbers of bedbugs of all development stages captured were significantly greater in traps with CO2 (chi2 = 15 942, d.f. = 1, P < 10(-9)). A non-parametric two-way analysis of variance evaluation of six different traps with or without CO2, heat or a chemical lure monitored over 19 trap-days in an infested apartment showed that trap type was highly significant (n = 2833 bedbugs collected) (P < 10(-7)). The trap with CO2, heat and a chemical lure captured more bedbugs than the other traps, but only caught significantly more fourth and fifth instar nymphs than all other traps. Otherwise, the catches in this trap did not differ significantly from those caught by traps that contained CO2 and heat only. The total numbers of bedbugs collected for each trapping date (pooling all six traps) followed an exponential decline over the trapping period. This type of trap, which caught bedbugs in unoccupied apartments with and without furniture, and in an occupied apartment, may have utility in studying the ecology of bedbugs, in detecting bedbug infestations and in reducing numbers of bites by trapping host-seeking bedbugs.

Progressive dementia after first-ever stroke: a community-based follow-up study.

OBJECTIVES: To examine the risk and determinants of a progressive dementia syndrome and cognitive impairment not dementia (CIND) in community-based nonaphasic first-ever stroke cases 1 year after stroke, relative to a matched community-based stroke-free group. METHODS: Matched cohort design, with cognitive tests given on two occasions 9 months apart to 99 mild-to-moderate first-ever stroke patients and 99 age- and sex-matched people without stroke. At follow-up, progressive dementia or CIND were diagnosed, with judges blinded to stroke/nonstroke status. RESULTS: Progressive dementia was diagnosed in 12.5% of stroke patients and 15.4% of those without strokes (RR 1.1, 95% CI 0.5 to 2.2, p = 0.85). CIND was diagnosed in 37.5% of stroke patients and 17.6% of participants without strokes (RR 2.1, 95% CI 1.2 to 3.4, p = 0.003). In multivariable regression, age (p = 0.04) and baseline cognition (p < 0.001) were independently associated with dementia whereas stroke (p = 0.002), age (p = 0.05), baseline cognition (p = 0.001), and baseline mood (p = 0.03) were independently associated with CIND at follow-up. CONCLUSIONS: In this community-based nonaphasic sample, mild-to moderate first-ever stroke was not associated with the presence of progressive dementia 1 year later, but was clearly associated with a greater risk of cognitive impairment not dementia (CIND). Baseline mood impairment remained independently associated with CIND at 1 year after taking into account stroke, age, and baseline cognitive ability.

A novel family of anticoagulants from the saliva of Ixodes scapularis.

Using biochemical and molecular approaches, we have identified a 9.8 kDa protein in the saliva of Ixodes scapularis that inhibits the intrinsic pathway of coagulation. The 9.8 kDa anticoagulant protein was purified by reverse-phase HPLC and its N-terminal amino acid sequence determined. The N-terminal sequence showed homology with Salp14, an immuno-dominant antigen present in the saliva of engorging I. scapularis nymphs. Recombinant Salp14 expressed in Escherichia coli prolonged the activated partial thromboplastin time (APTT) of human plasma in a dose-dependent manner and was a specific inhibitor of factor Xa. A cDNA encoding a 9.3 kDa protein, Salp9Pac, was subsequently isolated from an I. scapularis salivary gland cDNA library. Salp9Pac showed 93% identity to the N-terminal sequence of the anticoagulant purified by HPLC. These data indicate that the anticoagulant protein purified by HPLC, Salp9Pac and Salp14 are members of a family of novel coagulation protease inhibitors present in tick saliva. While recombinant Salp9Pac did not show biological activity in the assays tested currently, it is likely to be mechanistically different from its paralogues. This raises the possibility that ticks may enhance their adaptive ability to cope with a wide spectrum of proteases, by transcribing such structurally related anticoagulant proteins with different functions.

A phylogenetic approach to following West Nile virus in Connecticut.

The 1999 outbreak of West Nile (WN) virus in the northeastern United States was the first known natural occurrence of this flavivirus in the Western Hemisphere. In 1999 and 2000, 82 independent Connecticut WN virus isolates were cultured from nine species of birds, five species of mosquitoes, and one striped skunk. Nucleotide sequences obtained from these isolates identified 30 genetic changes, compared with WN-NY99, in a 921-nt region of the viral genome beginning at nucleotide position 205 and ending at 1125. This region encodes portions of the nucleocapsid and envelope proteins and includes the entire coding regions for the premembrane and membrane proteins. Amino acid changes occurred at seven loci in six isolates relative to the WN-NY99 strain. Although 34 of the isolates showed sequences identical to the WN-NY99 isolate, we were able to show geographical-based clusters of mutations. In particular, 26 isolates were characterized by mutation of C to T at position 858. This group apparently originated in Stamford, CT and disseminated to sites located as far as 54 miles from Stamford. Sequences of WN virus isolated from both brain and heart tissues from the same avian host were identical in all 14 tested individual birds, suggesting that the mutations we have documented are real and not caused by culture, RNA extraction, or PCR procedures. We conclude that this portion of the viral genome will enable us to follow the geographical and temporal movement of variant WN virus strains as they adapt to North America.

Immunization of mice against West Nile virus with recombinant envelope protein.

West Nile (WN) virus is a mosquito-borne flavivirus that emerged in the United States in 1999 and can cause fatal encephalitis. Envelope (E) protein cDNA from a WN virus isolate recovered from Culex pipiens in Connecticut was expressed in Escherichia coli. The recombinant E protein was purified and used as Ag in immunoblot assays and immunization experiments. Patients with WN virus infection had Abs that recognized the recombinant E protein. C3H/HeN mice immunized with E protein developed E protein Abs and were protected from infection with WN virus. Passive administration of E protein antisera was also sufficient to afford immunity. E protein is a candidate vaccine to prevent WN virus infection.

Mosquito surveillance for West Nile virus in Connecticut, 2000: isolation from Culex pipiens, Cx. restuans, Cx. salinarius, and Culiseta melanura.

Fourteen isolations of West Nile (WN) virus were obtained from four mosquito species (Culex pipiens [5], Cx. restuans [4], Cx. salinarius [2], and Culiseta melanura [3]) in statewide surveillance conducted from June through October 2000. Most isolates were obtained from mosquitoes collected in densely populated residential locales in Fairfield and New Haven counties, where the highest rates of dead crow sightings were reported and where WN virus was detected in 1999. Minimum field infection rates per 1,000 mosquitoes ranged from 0.5 to 1.8 (county based) and from 1.3 to 76.9 (site specific). Cx. restuans appears to be important in initiating WN virus transmission among birds in early summer; Cx. pipiens appears to play a greater role in amplifying virus later in the season. Cs. melanura could be important in the circulation of WN virus among birds in sylvan environments; Cx. salinarius is a suspected vector of WN virus to humans and horses.

Discovery, distribution, and abundance of the newly introduced mosquito Ochlerotatus japonicus (Diptera: Culicidae) in Connecticut, USA.

The earliest documented specimen of an exotic east Asian mosquito Ochlerotatus (Finlaya) japonicis japonicus (Theobald) in the Western Hemisphere is reported along with the results of a state wide survey to determine the distribution and abundance of this mosquito in Connecticut. Ochlerotatus japonicus was collected from 87 locations in eight counties. It is established throughout the state and occurs in a variety of natural and artificial container habitats including discarded tire casings, bird baths, wooden barrels, porcelain bath tubs (used for watering animals), plastic milk cartons, toys, vinyl tarpaulins (covering wood piles and swimming pools), exposed rock holes in stream beds, tree holes, subterranean catch basins, surface water rain pools, and spring-fed depressions. Larvae were particularly common in containers with water, decaying leaves, and algae, in shaded and sunlit areas and, in rock-pool habitats along streambeds, in association with Ochlerotatus atropalpus (Coquillett). Adult females were collected in sod grass-infused gravid and CO2- baited light traps, from early June through October, with peak collections in September. Biting females were collected by human bait method augmented with CO2, verifying its capacity to feed on humans. The ovitraps used in this study were not effective for recovering this species. Our results suggest that Oc. japonicus was introduced into Connecticut between 1992 and 1998. Because of the ability of Oc. japonicus to transmit West Nile virus, and because of the recent detection of this virus in field-collected specimens, the introduction of Oc. japonicus is considered a significant public health development.

Hamular frenum modification: a removable denture prosthesis retention and stability enhancement.

A removable denture prosthesis, whether partial or complete, often requires preprosthetic surgery to achieve optimum stabilization and retention. While the hamular frenum may produce significant dynamic dislodging forces, a literature review did not reveal any reports dealing with this problem. A hamular frenum reduction surgical procedure using the free autogenous gingival graft procedure is described. Prosthetic function may be enhanced by eliminating the dynamic disrupting force of the hamular frenum along with improving posterior maxillary tuberosity contour and, as necessary, premaxillary form, allowing these contours to work in concert to develop a "cupping" stabilizing and retentive complex.

West Nile virus envelope protein: role in diagnosis and immunity.

The role of antibodies to the West Nile virus envelope (E) protein in serodiagnosis and protection was examined. The E protein was expressed and purified in recombinant form. Antibodies to the E protein were detected in patients with West Nile virus infection. Passive immunization with rabbit anti-E protein sera also partially protected mice from challenge with West Nile virus. The humoral response to the West Nile virus E protein is therefore useful as an aid in the diagnosis and may also play a role in immunity to infection.

Detection of Ehrlichia chaffeensis DNA in Amblyomma americanum ticks in Connecticut and Rhode Island.

Ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis, is transmitted by Amblyomma americanum ticks, which are most abundant in the southern United States. Because serologic evidence suggests that residents of Connecticut are exposed to E. chaffeensis, A. americanum ticks were collected in Connecticut and Rhode Island for PCR analysis to detect E. chaffeensis DNA. Eight of 106 (7.6%) A. americanum ticks from Connecticut and 6 of 52 (11.5%) from Rhode Island contained E. chaffeensis DNA. Thus, E. chaffeensis is present in ticks in southern New England and transmission of E. chaffeensis may occur there.

Attachment of Borrelia burgdorferi within Ixodes scapularis mediated by outer surface protein A.

Borrelia burgdorferi outer surface protein (Osp) A has been used as a Lyme disease vaccine that blocks transmission: OspA antibodies of immune hosts enter ticks during blood feeding and destroy spirochetes before transmission to the host can occur. B. burgdorferi produce OspA in the gut of unfed Ixodes scapularis ticks, and many spirochetes repress OspA production during the feeding process. This preferential expression suggests that OspA may have an important function in the vector. Here we show that OspA mediates spirochete attachment to the tick gut by binding to an I. scapularis protein. The binding domains reside in the central region and COOH-terminus of OspA. OspA also binds to itself, suggesting that spirochete-spirochete interactions may further facilitate adherence in the gut. OspA-mediated attachment in the tick provides a possible mechanism for how stage-specific protein expression can contribute to pathogenesis during the B. burgdorferi natural cycle.

Recovery and identification of West Nile virus from a hawk in winter.

West Nile virus was recovered from the brain of a red-tailed hawk that died in Westchester County, N.Y., in February 2000. Multiple foci of glial cells, lymphocytes, and a few pyknotic nuclei were observed in the brain. Three to 4 days after inoculation of Vero cells with brain homogenates, cytopathic changes were detected. The presence of West Nile virus antigen in fixed cells or cell lysates was revealed by fluorescent antibody testing or enzyme-linked immunosorbent assay, respectively. Furthermore, Reverse transcriptase-PCR with primers specific for the NS3 gene of West Nile virus resulted in an amplicon of the expected size (470 bp). Electron microscopy of thin sections of infected Vero cells revealed the presence of viral particles approximately 40 nm in diameter, within cytoplasmic vesicles. The demonstration of infection with the West Nile virus in the dead of the winter, long after mosquitoes ceased to be active, is significant in that it testifies to the survival of the virus in the region beyond mosquito season and suggests another route of transmission: in this case, prey to predator.

SALP16, a gene induced in Ixodes scapularis salivary glands during tick feeding.

Guinea pigs infested with Ixodes scapularis acquire antibody-mediated resistance to tick bites, a phenomenon known as tick-immunity. An I. scapularis salivary gland cDNA expression library was therefore probed with sera from tick-immune guinea pigs to identify antigens that elicit humoral responses in the host. Sera from sensitized guinea pigs strongly recognized 3 of 4,500 library clones in an initial screening. The open reading frames of all 3 clones encoded a putative 16.4-kD acidic protein, designated Salp16, with an N-terminal signal sequence and signal peptidase cleavage sites specific for secretory proteins. The salp16 mRNA and Salp16 protein were detected in the salivary glands of engorged, but not unfed, nymphal and adult ticks, and Salp16 was also found in the saliva of engorged ticks. Immunization with recombinant Salp16 induced high antibody titers in guinea pigs, but did not elicit tick-immunity. Salp16 is the first feeding inducible gene that has been cloned from L. scapularis. Molecular characterization of I. scapularis salivary antigens that are induced upon tick feeding should help to facilitate our understanding of tick-host interactions.

Utilization of common analgesic and anxiolytic medications by registered First Nations residents of western Canada.

The study examined utilization of acetaminophen with codeine and benzodiazepine drugs among Non-Insured Health Benefits (NIHB) program registered First Nations residents in the four western provinces of Canada and sought preliminary indicators of factors influencing utilization. A small percentage of NIHB clients in the four western provinces were excessive users of acetaminophen with codeine and/or benzodiazepines, but overall utilization of these central nervous system drugs was moderate and within the bounds of non-First Nations population use examined in this study. The study also demonstrated that utilization of acetaminophen with codeine among NIHB claimants was inversely related to the stringency of provincial regulation.