Variable microbiomes between mosquito lines are maintained across different environments

The composition of the microbiome is shaped by both environment and host in most organisms, but in the mosquito Aedes aegypti the role of the host in shaping the microbiome is poorly understood. Previously, we had shown that four lines of Ae. aegypti harbored different microbiomes when reared in the same insectary under identical conditions. To determine whether these lines differed from each other across time and in different environments, we characterized the microbiome of the same four lines of Ae. aegypti reared in the original insectary and at another institution. While it was clear that the environment influenced the microbiomes of these lines, we did still observe distinct differences in the microbiome between lines within each insectary. Clear differences were observed in alpha diversity, beta diversity, and abundance of specific bacterial taxa. To determine if the line specific differences in the microbiome were maintained across environments, pair-wise differential abundances of taxa was compared between insectaries. Lines were most similar to other lines from the same insectary than to the same line reared in a different insectary. Additionally, relatively few differentially abundant taxa identified between pairs of lines were shared across insectaries, indicating that line specific properties of the microbiome are not conserved across environments, or that there were distinct microbiota within each insectary. Overall, these results demonstrate that mosquito lines under the same environmental conditions have different microbiomes across microbially- diverse environments and host by microbe interactions affecting microbiome composition and abundance is dependent on environmentally available bacteria.

Analysis of SARS-CoV-2 in Nasopharyngeal Samples from Patients with COVID-19 Illustrates Population Variation and Diverse Phenotypes, Placing the Growth Properties of Variants of Concern in Context with Other Lineages

New variants of SARS-CoV-2 are continuing to emerge and dominate the global sequence landscapes. Several variants have been labeled variants of concern (VOCs) because they may have a transmission advantage, increased risk of morbidity and/or mortality, or immune evasion upon a background of prior infection or vaccination. Placing the VOCs in context with the underlying variability of SARS-CoV-2 is essential in understanding virus evolution and selection pressures. Dominant genome sequences and the population genetics of SARS-CoV-2 in nasopharyngeal swabs from hospitalized patients were characterized. Nonsynonymous changes at a minor variant level were identified. These populations were generally preserved when isolates were amplified in cell culture. To place the Alpha, Beta, Delta, and Omicron VOCs in context, their growth was compared to clinical isolates of different lineages from earlier in the pandemic. The data indicated that the growth in cell culture of the Beta variant was more than that of the other variants in Vero E6 cells but not in hACE2-A549 cells. Looking at each time point, Beta grew more than the other VOCs in hACE2-A549 cells at 24 to 48 h postinfection. At 72 h postinfection there was no difference in the growth of any of the variants in either cell line. Overall, this work suggested that exploring the biology of SARS-CoV-2 is complicated by population dynamics and that these need to be considered with new variants. In the context of variation seen in other coronaviruses, the variants currently observed for SARS-CoV-2 are very similar in terms of their clinical spectrum of disease. IMPORTANCE SARS-CoV-2 is the causative agent of COVID-19. The virus has spread across the planet, causing a global pandemic. In common with other coronaviruses, SARS-CoV-2 genomes can become quite diverse as a consequence of replicating inside cells. This has given rise to multiple variants from the original virus that infected humans. These variants may have different properties and in the context of a widespread vaccination program may render vaccines less effective. Our research confirms the degree of genetic diversity of SARS-CoV-2 in patients. By comparing the growth of previous variants to the pattern seen with four variants of concern (VOCs) (Alpha, Beta, Delta, and Omicron), we show that, at least in cells, Beta variant growth exceeds that of Alpha, Delta, and Omicron VOCs at 24 to 48 h in both Vero E6 and hACE2-A549 cells, but by 72 h postinfection, the amount of virus is not different from that of the other VOCs.

CPC-containing oral rinses inactivate SARS-CoV-2 variants and are active in the presence of human saliva

Introduction. The importance of human saliva in aerosol-based transmission of SARS-CoV-2 is now widely recognized. However, little is known about the efficacy of virucidal mouthwash formulations against emergent SARS-CoV-2 variants of concern and in the presence of saliva.

Hypothesis. Mouthwashes containing virucidal actives will have similar inactivation effects against multiple SARS-CoV-2 variants of concern and will retain efficacy in the presence of human saliva.

Aim. To examine in vitro efficacy of mouthwash formulations to inactivate SARS-CoV-2 variants.

Methodology. Inactivation of SARS-CoV-2 variants by mouthwash formulations in the presence or absence of human saliva was assayed using ASTM International Standard E1052-20 methodology.

Results. Appropriately formulated mouthwashes containing 0.07 % cetylpyridinium chloride but not 0.2 % chlorhexidine completely inactivated SARS-CoV-2 (USA-WA1/2020, Alpha, Beta, Gamma, Delta) up to the limit of detection in suspension assays. Tests using USA-WA1/2020 indicates that efficacy is maintained in the presence of human saliva.

Conclusions. Together these data suggest cetylpyridinium chloride-based mouthwashes are effective at inactivating SARS-CoV-2 variants. This indicates potential to reduce viral load in the oral cavity and mitigate transmission via salivary aerosols.

Methods of SARS-CoV-2 Inactivation

Inactivation methods allow for hazard group 3 (HG3) pathogens to be disposed of and used safely in downstream experiments and assays to be carried out at lower containment levels. Commonly used viral inactivation methods include heat inactivation, fixation methods, ultraviolet (UV) light and detergent inactivation. Here we describe known methods used to inactivate SARS-CoV-2 for safe downstream biological assays.

Long-term persistence of neutralizing SARS-CoV-2 antibodies in pets

We monitored the severe acute respiratory syndrome coronavirus 2 antibody response in seven dogs and two cats by using two multispecies ELISA tests, plaque reduction neutralisation test and virus neutralization. SARS‐CoV‐2 neutralizing antibodies in pets persisted up to 10 months since the first positive testing, thus replicating observations in COVID‐19 human patients.

SARS-CoV-2 neutralising antibodies in dogs and cats in the United Kingdom

Companion animals are susceptible to SARS-CoV-2 infection and sporadic cases of pet infections have occurred in the United Kingdom. Here we present the first large-scale serological survey of SARS-CoV-2 neutralising antibodies in dogs and cats in the UK. Results are reported for 688 sera (454 canine, 234 feline) collected by a large veterinary diagnostic laboratory for routine haematology during three time periods; pre-COVID-19 (January 2020), during the first wave of UK human infections (April–May 2020) and during the second wave of UK human infections (September 2020–February 2021). Both pre-COVID-19 sera and those from the first wave tested negative. However, in sera collected during the second wave, 1.4% (n ​= ​4) of dogs and 2.2% (n ​= ​2) of cats tested positive for neutralising antibodies. The low numbers of animals testing positive suggests pet animals are unlikely to be a major reservoir for human infection in the UK. However, continued surveillance of in-contact susceptible animals should be performed as part of ongoing population health surveillance initiatives.

SARS-CoV-2 neutralising antibodies in Dogs and Cats in the United Kingdom

Companion animals are susceptible to SARS-CoV-2 infection and sporadic cases of pet infections have occurred in the United Kingdom. Here we present the first large-scale serological survey of SARS-CoV-2 neutralising antibodies in dogs and cats in the UK. Results are reported for 688 sera (454 canine, 234 feline) collected by a large veterinary diagnostic laboratory for routine haematology during three time periods; pre-COVID-19 (January 2020), during the first wave of UK human infections (April-May 2020) and during the second wave of UK human infections (September 2020-February 2021). Both pre-COVID-19 sera and those from the first wave tested negative. However, in sera collected during the second wave, 1.4% (n=4) of dogs and 2.2% (n=2) cats tested positive for neutralising antibodies. The low numbers of animals testing positive suggests pet animals are unlikely to be a major reservoir for human infection in the UK. However, continued surveillance of in-contact susceptible animals should be performed as part of ongoing population health surveillance initiatives.

Inactivation of SARS-CoV-2 on surfaces and in solution with Virusend (TX-10), a novel disinfectant

Until an effective vaccine against SARS-CoV-2 is available on a widespread scale, the control of the COVID-19 pandemic is reliant upon effective pandemic control measures. The ability of SARS-CoV-2 to remain viable on surfaces and in aerosols, means indirect contact transmission can occur and there is an opportunity to reduce transmission using effective disinfectants in public and communal spaces. Virusend (TX-10), a novel disinfectant, has been developed as a highly effective disinfectant against a range of microbial agents. Here we investigate the ability of Virusend to inactivate SARS-CoV-2. Using surface and solution inactivation assays, we show that Virusend is able to reduce SARS-CoV-2 viral titre by 4 log10 p.f.u. ml-1 within 1 min of contact. Ensuring disinfectants are highly effective against SARS-CoV-2 is important in eliminating environmental sources of the virus to control the COVID-19 pandemic.

Stable high-density and maternally inherited Wolbachia infections in Anopheles moucheti and Anopheles demeilloni mosquitoes

Wolbachia, a widespread bacterium that can reduce pathogen transmission in mosquitoes, has recently been reported to be present in Anopheles (An.) species. In wild populations of the An. gambiae complex, the primary vectors of Plasmodium malaria in Sub-Saharan Africa, Wolbachia DNA sequences at low density and infection frequencies have been detected. As the majority of studies have used highly sensitive nested PCR as the only method of detection, more robust evidence is required to determine whether Wolbachia strains are established as endosymbionts in Anopheles species. Here, we describe high-density Wolbachia infections in geographically diverse populations of An. moucheti and An. demeilloni. Fluorescent in situ hybridization localized a heavy infection in the ovaries of An. moucheti, and maternal transmission was observed. Genome sequencing of both Wolbachia strains obtained genome depths and coverages comparable to those of other known infections. Notably, homologs of cytoplasmic incompatibility factor (cif) genes were present, indicating that these strains possess the capacity to induce the cytoplasmic incompatibility phenotype, which allows Wolbachia to spread through host populations. These strains should be further investigated as candidates for use in Wolbachia biocontrol strategies in Anopheles aiming to reduce the transmission of malaria.

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High-density Wolbachia strains found in An. moucheti and An. demeilloni mosquitoes

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Infections are visualized in the ovaries, and maternal transmission was observed

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Sequencing at depths and coverages comparable to other known Wolbachia strains

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Homologs of cytoplasmic incompatibility factor genes are present in both genomes

Evidence of exposure to SARS-CoV-2 in cats and dogs from households in Italy

SARS-CoV-2 emerged from animals and is now easily transmitted between people. Sporadic detection of natural cases in animals alongside successful experimental infections of pets, such as cats, ferrets and dogs, raises questions about the susceptibility of animals under natural conditions of pet ownership. Here, we report a large-scale study to assess SARS-CoV-2 infection in 919 companion animals living in northern Italy, sampled at a time of frequent human infection. No animals tested PCR positive. However, 3.3% of dogs and 5.8% of cats had measurable SARS-CoV-2 neutralizing antibody titers, with dogs from COVID-19 positive households being significantly more likely to test positive than those from COVID-19 negative households. Understanding risk factors associated with this and their potential to infect other species requires urgent investigation.

Methods of Inactivation of SARS-CoV-2 for Downstream Biological Assays

The scientific community has responded to the coronavirus disease 2019 (COVID-19) pandemic by rapidly undertaking research to find effective strategies to reduce the burden of this disease. Encouragingly, researchers from a diverse array of fields are collectively working towards this goal. Research with infectious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is undertaken in high-containment laboratories; however, it is often desirable to work with samples at lower-containment levels. To facilitate the transfer of infectious samples from high-containment laboratories, we have tested methods commonly used to inactivate virus and prepare the sample for additional experiments. Incubation at 80°C, a range of detergents, Trizol reagents, and UV energies were successful at inactivating a high titer of SARS-CoV-2. Methanol and paraformaldehyde incubation of infected cells also inactivated the virus. These protocols can provide a framework for in-house inactivation of SARS-CoV-2 in other laboratories, ensuring the safe use of samples in lower-containment levels.

Microbial interactions in the mosquito gut determine Serratia colonization and blood-feeding propensity

How microbe–microbe interactions dictate microbial complexity in the mosquito gut is unclear. Previously we found that, Serratia, a gut symbiont that alters vector competence and is being considered for vector control, poorly colonized Aedes aegypti yet was abundant in Culex quinquefasciatus reared under identical conditions. To investigate the incompatibility between Serratia and Ae. aegypti, we characterized two distinct strains of Serratia marcescens from Cx. quinquefasciatus and examined their ability to infect Ae. aegypti. Both Serratia strains poorly infected Ae. aegypti, but when microbiome homeostasis was disrupted, the prevalence and titers of Serratia were similar to the infection in its native host. Examination of multiple genetically diverse Ae. aegypti lines found microbial interference to S. marcescens was commonplace, however, one line of Ae. aegypti was susceptible to infection. Microbiome analysis of resistant and susceptible lines indicated an inverse correlation between Enterobacteriaceae bacteria and Serratia, and experimental co-infections in a gnotobiotic system recapitulated the interference phenotype. Furthermore, we observed an effect on host behavior; Serratia exposure to Ae. aegypti disrupted their feeding behavior, and this phenotype was also reliant on interactions with their native microbiota. Our work highlights the complexity of host–microbe interactions and provides evidence that microbial interactions influence mosquito behavior.

Evidence of exposure to SARS-CoV-2 in cats and dogs from households in Italy

SARS-CoV-2 originated in animals and is now easily transmitted between people. Sporadic detection of natural cases in animals alongside successful experimental infections of pets, such as cats, ferrets and dogs, raises questions about the susceptibility of animals under natural conditions of pet ownership. Here we report a large-scale study to assess SARS-CoV-2 infection in 817 companion animals living in northern Italy, sampled at a time of frequent human infection. No animals tested PCR positive. However, 3.4% of dogs and 3.9% of cats had measurable SARS-CoV-2 neutralizing antibody titers, with dogs from COVID-19 positive households being significantly more likely to test positive than those from COVID-19 negative households. Understanding risk factors associated with this and their potential to infect other species requires urgent investigation.

One Sentence Summary

SARS-CoV-2 antibodies in pets from Italy.

CRISPR/Cas9-mediated gene deletion of the ompA gene in symbiotic Cedecea neteri impairs biofilm formation and reduces gut colonization of Aedes aegypti mosquitoes

BACKGROUND

Symbiotic bacteria are pervasive in mosquitoes and their presence can influence many host phenotypes that affect vectoral capacity. While it is evident that environmental and host genetic factors contribute in shaping the microbiome of mosquitoes, we have a poor understanding regarding how bacterial genetics affects colonization of the mosquito gut. The CRISPR/Cas9 gene editing system is a powerful tool to alter bacterial genomes facilitating investigations into host-microbe interactions but has yet to be applied to insect symbionts.

METHODOLOGY/PRINCIPAL FINDINGS

To investigate the role of bacterial genetic factors in mosquito biology and in colonization of mosquitoes we used CRISPR/Cas9 gene editing system to mutate the outer membrane protein A (ompA) gene of a Cedecea neteri symbiont isolated from Aedes mosquitoes. The ompA mutant had an impaired ability to form biofilms and poorly infected Ae. aegypti when reared in a mono-association under gnotobiotic conditions. In adult mosquitoes, the mutant had a significantly reduced infection prevalence compared to the wild type or complement strains, while no differences in prevalence were seen in larvae, suggesting genetic factors are particularly important for adult gut colonization. We also used the CRISPR/Cas9 system to integrate genes (antibiotic resistance and fluorescent markers) into the symbionts genome and demonstrated that these genes were functional in vitro and in vivo.

CONCLUSIONS/SIGNIFICANCE

Our results shed insights into the role of ompA gene in host-microbe interactions in Ae. aegypti and confirm that CRISPR/Cas9 gene editing can be employed for genetic manipulation of non-model gut microbes. The ability to use this technology for site-specific integration of genes into the symbiont will facilitate the development of paratransgenic control strategies to interfere with arboviral pathogens such Chikungunya, dengue, Zika and Yellow fever viruses transmitted by Aedes mosquitoes.

Pressure, compressibility, and contact of the two-dimensional attractive fermi gas

Using ab initio lattice methods, we calculate the finite temperature thermodynamics of homogeneous two-dimensional spin-1/2 fermions with attractive short-range interactions. We present results for the density, pressure, compressibility, and quantum anomaly (i.e., Tan's contact) for a wide range of temperatures (mostly above the superfluid phase, including the pseudogap regime) and coupling strengths, focusing on the unpolarized case. Within our statistical and systematic uncertainties, our prediction for the density equation of state differs quantitatively from the prediction by Luttinger-Ward theory in the strongly coupled region of parameter space, but otherwise agrees well with it. We also compare our calculations with the second- and third-order virial expansion, with which they are in excellent agreement in the low-fugacity regime.

Deep-vein thrombosis in high-energy skeletal trauma despite thromboprophylaxis

We report the incidence and location of deep-vein thrombosis in 312 patients who had sustained high-energy, skeletal trauma. They were investigated using magnetic resonance venography and Duplex ultrasound.

Despite thromboprophylaxis, 36 (11.5%) developed venous thromboembolic disease with an incidence of 10% in those with non-pelvic trauma and 12.2% in the group with pelvic trauma. Of patients who developed deep-vein thrombosis, 13 of 27 in the pelvic group (48%) and only one of nine in the non-pelvic group (11%) had a definite pelvic deep-vein thrombosis. When compared with magnetic resonance venography, ultrasound had a false-negative rate of 77% in diagnosing pelvic deep-vein thrombosis. Its value in the pelvis was limited, although it was more accurate than magnetic resonance venography in diagnosing clots in the lower limbs. Additional screening may be needed to detect pelvic deep-vein thrombosis in patients with pelvic or acetabular fractures.

Wound drainage for caesarean section

BACKGROUND

Subcutaneous and sub rectus sheath wound drains are sometimes used in women who have undergone caesarean section. The indications for using drains vary by clinician.

OBJECTIVES

To compare the effects of using a wound drain with not using a wound drain at caesarean section, and of different types of drain, on maternal health and healthcare resource use.

SEARCH STRATEGY

This review draws on the search strategy developed for the Cochrane Wounds Group as a whole. Electronic databases (MEDLINE, EMBASE, Cinahl and CAB Health), and the reference lists of included articles were also searched up to June 2004

SELECTION CRITERIA

Studies were included if they allocated women to groups at random and they compared any type of wound drain with no wound drainage, or with any other type of drain, in women undergoing caesarean section.

DATA COLLECTION AND ANALYSIS

Trials were evaluated for appropriateness for inclusion and methodological quality without consideration of their results. This was done by two reviewers according to pre-stated eligibility criteria.

MAIN RESULTS

Seven trials (1993 women) were included in the review. Meta-analysis found no difference in the risk of wound infection, other wound complications, febrile morbidity or endometritis in women who had wound drains compared with those who did not. There was some evidence that caesarean sections may be about five minutes shorter and that blood loss may be slightly lower when drains were not used.

AUTHORS' CONCLUSIONS

There is no evidence in the seven small trials included to suggest that the routine use of wound drains at caesarean section confers any benefit on the women involved. These trials do not answer the question of whether wound drainage is of benefit when haemostasis is not felt to be adequate. Further large trials are justified using blinded outcome assessment to examine the role of different types of wound drain at caesarean section. Comparing the use of drains in women with different degrees of obesity and in women having first or repeat caesareans and intrapartum or prelabour caesarean sections would be of interest. Women's views and experience of drains have not been studied in these trials.

Techniques and materials for closure of the abdominal wall in caesarean section

BACKGROUND

There is a variety of techniques for closing the abdominal wall during caesarean section. Some methods may be better in terms of postoperative recovery and other important outcomes.

OBJECTIVES

To compare the effects of alternative techniques for closure of the rectus sheath and subcutaneous fat on maternal health and healthcare resource use.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register (September 2003), MEDLINE (1966 to September 2003), EMBASE (1980 to September 2003), CINAHL (1983 to September 2003) and CAB Health (1973 to September 2003), and the reference lists of included articles.

SELECTION CRITERIA

Randomised trials making any of the following comparisons: (a) any suturing technique or material used for closure of the rectus sheath versus any other; (b) closure versus non-closure of subcutaneous fat; (c) any suturing technique or material used for closure of the subcutaneous fat versus any other; (d) any type of needle for repair of the abdominal wall in caesarean section versus any other; (e) any other comparison of methods of abdominal wall closure.

DATA COLLECTION AND ANALYSIS

Both reviewers evaluated trials for eligibility and methodological quality without consideration of their results.

MAIN RESULTS

Seven studies involving 2056 women were included. The risk of haematoma or seroma was reduced with fat closure compared with non-closure (relative risk (RR) 0.52, 95% confidence interval (CI) 0.33 to 0.82), as was the risk of 'wound complication' (haematoma, seroma, wound infection or wound separation) (RR 0.68, 95% CI 0.52 to 0.88). No difference in the risk of wound infection alone or other short-term outcomes was found. No long-term outcomes were reported. There was no difference in the risk of wound infection between blunt needles and sharp needles in one small study. No studies were found examining suture techniques or materials for closure of the rectus sheath or subcutaneous fat.

IMPLICATIONS FOR PRACTICE

Closure of the subcutaneous fat may reduce wound complications but it is unclear to what extent these differences affect the well-being and satisfaction of the women concerned.

IMPLICATIONS FOR RESEARCH

Further trials are justified to investigate whether the apparent increased risk of haematoma or seroma with non-closure of the subcutaneous fat is real. These should use a broader range of short- and long-term outcomes, and ensure that they are adequately powered to detect clinically important differences. Further research comparing blunt and sharp needles is justified, as are trials evaluating suturing materials and suturing techniques for the rectus sheath.

Hippocampal synaptic dysfunction in a murine model of human immunodeficiency virus type 1 encephalitis

Alterations in hippocampal physiology affect cognition in human immunodeficiency virus type 1 (HIV-1)-associated dementia (HAD). The mechanism for how this occurs is not well understood. To address this, we investigated how changes in synaptic transmission and plasticity are affected by viral infection and macrophage activation using a severe combined immunodeficiency mouse model of human HIV-1 encephalitis (HIVE). HIVE was induced in mice by stereotactic injection of HIV-1-infected human monocyte-derived macrophages (MDM) into the striatum. Animals were sacrificed after 3, 7 and 15 days. Hippocampal slices were prepared from HIV-1, MDM- and sham-injected animals. Electrically evoked field excitatory postsynaptic potentials were recorded in the CA1 region of the hippocampus. Neuronal physiology was assessed by input-output and by long-term potentiation (LTP) assays. We observed that a higher stimulation intensity (mA) was required to induce a 1-mV response in the HIVE mice (0.32+/-0.06) compared with shams (0.17+/-0.01) at day 7. The stimulation intensities at day 15 were 0.44+/-0.07 and 0.23+/-0.05 in the HIVE and shams, respectively. An impairment of synaptic function was detected through measuring synaptic responses induced by stimuli with different intensities. Paired-pulse facilitation (PPF) showed deficits in HIVE mice at days 3, 7, and 15. At day 3, PPF ratios were 1.13+/-0.02 and 1.24+/-0.04 in HIVE and sham. The induction and maintenance of LTP was also impaired in HIVE mice. The average magnitude of LTP was 131.23+/-15.26% of basal in HIVE as compared with sham animals of 232.63+/-24.18%. MDM-injected mice showed an intermediate response. Taken together, the results show a range of neuronal synaptic transmission and plasticity changes in HIVE mice that may reflect the mechanisms of cognitive dysfunction in human HAD.

Spinal cord regeneration: moving tentatively towards new perspectives

The failure of the adult human spinal cord to regenerate following injury is not absolute, but appears to be amenable to therapeutic manipulation. Recent work has shown that the provision of a growth permissive environment by the neutralization of inhibitory influences, or the grafting of fetal tissue, peripheral nerve, Schwann cells, or olfactory ensheathing cells can enhance regeneration in animal models of spinal cord injury. Stem cells are gaining ever-increasing favour as a treatment option for spinal cord injury. The potential of neural stem cells, embryonic stem cells, and bone marrow stromal cells is discussed. Additional treatment options such as pharmacological interventions, functional electrical stimulation and physiotherapy approaches are also explored. Basic science insights are used as a foundation for a discussion of a variety of clinical perspectives including repair of the chronically injured spinal cord, animal models of human spinal cord injuries and clinical trials. A more holistic approach towards spinal cord injury is suggested, one where a hierarchy of needs is recognised and quality of life is paramount. Finally, this review cautions against overly grandiose claims of an imminent miracle cure for human spinal cord injury.

An experimental evaluation of theory-based mother and mother-child programs for children of divorce

This study evaluated the efficacy of 2 theory-based preventive interventions for divorced families: a program for mothers and a dual component mother-child program. The mother program targeted mother-child relationship quality, discipline, interparental conflict, and the father-child relationship. The child program targeted active coping, avoidant coping, appraisals of divorce stressors, and mother-child relationship quality. Families with a 9- to 12-year-old child (N = 240) were randomly assigned to the mother, dual-component, or self-study program. Postintervention comparisons showed significant positive program effects of the mother program versus self-study condition on relationship quality, discipline, attitude toward father-child contact, and adjustment problems. For several outcomes, more positive effects occurred in families with poorer initial functioning. Program effects on externalizing problems were maintained at 6-month follow-up. A few additive effects of the dual-component program occurred for the putative mediators; none occurred for adjustment problems.

Temporal lobe volume in panic disorder--a quantitative magnetic resonance imaging study

Although previous studies have used magnetic resonance imaging (MRI) to demonstrate qualitative abnormalities of the temporal lobes in patients with panic disorder, no study to date has applied quantitative volumetric methods to evaluate brain changes in panic disorder. The purpose of this study was to measure the volume of the temporal lobe and the hippocampus in patients with panic disorder and healthy control subjects using quantitative MRI measures. The volume of the temporal lobe, hippocampus and whole brain was measured in 13 patients with panic disorder and 14 healthy subjects. The mean volume of the left and right temporal lobes was significantly smaller in panic disorder compared to healthy subjects (16770+/-909 mm(3) vs. 18343+/-1740 mm(3)). This result was significant after controlling for differences in whole brain volume. There was no significant difference in volume of the hippocampus between patients and control subjects. These findings are consistent with smaller temporal lobe volume in panic disorder despite normal hippocampal volume.

Hippocampal volume reduction in major depression

OBJECTIVE

Elevated levels of glucocorticoids in depression have been hypothesized to be associated with damage to the hippocampus, a brain area involved in learning and memory. The purpose of this study was to measure hippocampal volume in patients with depression.

METHOD

Magnetic resonance imaging was used to measure the volume of the hippocampus in 16 patients with major depression in remission and 16 case-matched nondepressed comparison subjects.

RESULTS

Patients with depression had a statistically significant 19% smaller left hippocampal volume than comparison subjects, without smaller volumes of comparison regions (amygdala, caudate, frontal lobe, and temporal lobe) or whole brain volume. The findings were significant after brain size, alcohol exposure, age, and education were controlled for.

CONCLUSIONS

These findings are consistent with smaller left hippocampal volume in depression.

Clinimetric evaluation of the Sinonasal Outcome Test-16. Student Research Award 1998

This study describes the reliability, validity, and responsiveness of the Sinonasal Outcome Test-16 (SNOT-16), a rhinosinusitis-specific health-related quality-of-life instrument, in the University of Washington Department of Otolaryngology-Head and Neck Surgery patient population. The SNOT-16 was completed by 47, 24, and 22 patients at weeks 0, 6, and 12, respectively. In addition, all 47 patients completed the Short-form 36-item Health Survey (SF-36) at week 0. Furthermore, an additional cohort of patients from the otology clinic who denied symptoms of rhinosinusitis or previous physician diagnoses of rhinosinusitis were asked to complete the SNOT-16. These scores were subsequently used to determine discriminant validity of the instrument. Cronbach's alpha was 0.89, indicating a high degree of homogeneity of the test items. The SNOT-16 demonstrated excellent discriminant validity, and mean total SNOT-16 scores were significantly correlated with patient-reported overall health, overall bother, and 7 of the 8 SF-36 subscales. The standardized response mean calculated between weeks 0 and 6 was 0.69, indicating moderate sensitivity to change. We conclude that the SNOT-16 is a reliable, valid, and responsive instrument for measuring rhinosinusitis-specific health-related quality of life.

Don't know, don't care. III

The knowledge of and interest in Department of Defense programs to help medical students with their educational expenses in exchange for military service as a physician was studied at three medical schools representing the eastern (University of Medicine and Dentistry of New Jersey/New Jersey Medical School [UMDNJ/NJMS]), midwestern (University of Missouri at Kansas City), and western (University of Utah) United States. Despite staggering indebtedness (40% of the class of 1998 at the University of Medicine and Dentistry of New Jersey were in debt in excess of $100,000 at graduation), surprisingly few students were aware of programs such as the Health Professions Scholarship Program, the Health Professionals Loan Repayment Program, and the Specialized Training Assistance Program. Even fewer were interested when made aware of such financial assistance. Hostility to military service as a physician was common. "Patriotism" was seemingly anathema. Dwindling recruitment and retention of medical corps officers in the reserve components of our nation's armed forces is of grave concern to national security and flies in the face of medical students', hence young physicians', indebtedness for their education. Clearly Department of Defense programs must become more imaginative, certainly more financially appealing.

Non-invasive measurements of breast tissue optical properties using frequency-domain photon migration

A multiwavelength, high bandwidth (1 GHz) frequency-domain photon migration (FDPM) instrument has been developed for quantitative, non-invasive measurements of tissue optical and physiological properties. The instrument produces 300 kHz to 1 GHz photon density waves (PDWs) in optically turbid media using a network analyser, an avalanche photodiode detector and four amplitude-modulated diode lasers (674 nm, 811 nm, 849 nm, and 956 nm). The frequency of PDW phase and amplitude is measured and compared to analytically derived model functions in order to calculate absorption, mu a, and reduced scattering, mu s, parameters. The wavelength-dependence of absorption is used to determine tissue haemoglobin concentration (total, oxy- and deoxy- forms), oxygen saturation and water concentration. We present preliminary results of non-invasive FDPM measurements obtained from normal and tumour-containing human breast tissue. Our data clearly demonstrate that physiological changes caused by the presence of small (about 1 cm diameter) palpable lesions can be detected using a handheld FDPM probe.

Frequency-domain photon migration measurements of normal and malignant tissue optical properties in a human subject

A 1-GHz multifrequency, multiwavelength frequency-domain photon migration instrument is used to measure quantitatively the optical absorption (mu(a)) and effective optical scattering (mu(s) ?) of normal and malignant tissues in a human subject. Large ellipsoidal (~10-cm major axis, ~6-cm minor axes) subcutaneous malignant lesions were compared with adjacent normal sites in the abdomen and back. Absorption coefficients recorded at 674, 811, 849, and 956 nm were used to calculate tissue hemoglobin concentration (oxyhemoglobin, deoxyhemoglobin, and total), water concentration, hemoglobin oxygen saturation, and blood volume fraction in vivo. Our results show that the normal and the malignant tissues measured in the patient have clearly resolvable optical and physiological property differences that may be broadly useful in identifying and characterizing tumors.

Differential Rotation and Dynamics of the Solar Interior

Splitting of the sun's global oscillation frequencies by large-scale flows can be used to investigate how rotation varies with radius and latitude within the solar interior. The nearly uninterrupted observations by the Global Oscillation Network Group (GONG) yield oscillation power spectra with high duty cycles and high signal-to-noise ratios. Frequency splittings derived from GONG observations confirm that the variation of rotation rate with latitude seen at the surface carries through much of the convection zone, at the base of which is an adjustment layer leading to latitudinally independent rotation at greater depths. A distinctive shear layer just below the surface is discernible at low to mid-latitudes.

The Solar Acoustic Spectrum and Eigenmode Parameters

The Global Oscillation Network Group (GONG) project estimates the frequencies, amplitudes, and linewidths of more than 250,000 acoustic resonances of the sun from data sets lasting 36 days. The frequency resolution of a single data set is 0.321 microhertz. For frequencies averaged over the azimuthal order m, the median formal error is 0.044 microhertz, and the associated median fractional error is 1.6 x 10(-5). For a 3-year data set, the fractional error is expected to be 3 x 10(-6). The GONG m-averaged frequency measurements differ from other helioseismic data sets by 0.03 to 0.08 microhertz. The differences arise from a combination of systematic errors, random errors, and possible changes in solar structure.

The Current State of Solar Modeling

Data from the Global Oscillation Network Group (GONG) project and other helioseismic experiments provide a test for models of stellar interiors and for the thermodynamic and radiative properties, on which the models depend, of matter under the extreme conditions found in the sun. Current models are in agreement with the helioseismic inferences, which suggests, for example, that the disagreement between the predicted and observed fluxes of neutrinos from the sun is not caused by errors in the models. However, the GONG data reveal subtle errors in the models, such as an excess in sound speed just beneath the convection zone. These discrepancies indicate effects that have so far not been correctly accounted for; for example, it is plausible that the sound-speed differences reflect weak mixing in stellar interiors, of potential importance to the overall evolution of stars and ultimately to estimates of the age of the galaxy based on stellar evolution calculations.

Genetic questions for environmental studies. Differential parenting and psychopathology in adolescence

BACKGROUND

Recent genetic evidence suggests that the most important environmental influences on normal and pathologic development are those that are not shared by siblings in the same family. We sought to determine the relationship between differences in parenting styles and depressive symptoms and antisocial behavior in adolescence, and to compare the influence of these nonshared experiences with genetic influences.

METHODS

We studied 708 families with at least two same-sexed adolescent siblings who were monozygotic twins (93 families), dizygotic twins (99 families), ordinary siblings (95 families), full siblings in step families (181 families), half siblings in step families (110 families), and genetically unrelated siblings in step families (130 families). Data on parenting style were collected by questionnaire and by video recording of interaction between parents and children.

RESULTS

Almost 60% of variance in adolescent antisocial behavior and 37% of variance in depressive symptoms could be accounted for by conflictual and negative parental behavior directed specifically at the adolescent. In contrast, when a parent directed harsh, aggressive, explosive, and inconsistent parenting toward the sibling, we found less psychopathologic outcome in the adolescent.

CONCLUSIONS

Parenting behavior directed specifically at each child in the family is a major correlate of symptoms in adolescents. Furthermore, harsh parental behavior directed at a sibling may have protective effects for adolescents, a phenomenon we call the "siblin barricade."

Portable, high-bandwidth frequency-domain photon migration instrument for tissue spectroscopy

We describe a novel frequency-domain photon migration instrument employing direct diode laser modulation and avalanche photodiode detection, which is capable of noninvasively determinating the optical properties of biological tissues in near real time. An infinite medium diffusion model was used to extract absorption and transport scattering coefficients from 300-kHz to 800-MHz photon-density wave phase data. Optical properties measured in tissue-simulating solutions at 670 nm agreed to within 10% of those expected.

Analyzing change in short-term longitudinal research using cohort-sequential designs

This article illustrates a method for approximating longitudinal data analysis by combining information from different overlapping age groups to form a single developmental growth curve. Using this method, hypotheses about the form of growth, the extent of individual differences in growth, and factors that affect the rate and pattern of growth are investigated. The example used to illustrate this method examines the growth of externalizing behavior and of negativity in parent-child relationships during early adolescence using assessments from multiple methods and multiple informants. These 3 dimensions changed significantly during this period, with parental negativity increasing more rapidly after age 12. However, there were substantial individual differences in the pattern of change in these dimensions. Gender of child and type of family situation (nondivorced, divorced, and remarried) were investigated as possible factors affecting change.

Analyzing change in short-term longitudinal research using cohort-sequential designs

This article illustrates a method for approximating longitudinal data analysis by combining information from different overlapping age groups to form a single developmental growth curve. Using this method, hypotheses about the form of growth, the extent of individual differences in growth, and factors that affect the rate and pattern of growth are investigated. The example used to illustrate this method examines the growth of externalizing behavior and of negativity in parent-child relationships during early adolescence using assessments from multiple methods and multiple informants. These 3 dimensions changed significantly during this period, with parental negativity increasing more rapidly after age 12. However, there were substantial individual differences in the pattern of change in these dimensions. Gender of child and type of family situation (nondivorced, divorced, and remarried) were investigated as possible factors affecting change.

Blood pressure, hemodynamic, and thermal responses after cycling exercise

Seated recovery [at 5, 15, 20, 40, and 60 min (R5,15,20,40,60)] body temperature (T) and blood pressure were examined after 45 min of cycling exercise (54 +/- 5% maximal O2 uptake) in 12 normotensive males to study the relationship between postexercise thermal and hemodynamic responses. Data were analyzed with a repeated-measures analysis of variance. Systolic (SBP, R15,20,40; P < 0.01) and mean arterial (MAP, R15,20; P < 0.05) blood pressures were significantly lower, but diastolic blood pressure (DBP) was unchanged. Heart rate (R5,15,20, P < 0.001) was above that measured at rest. Decreases in mean skin T (Tsk, R15,20,60; P < 0.01) and increases in core T (Tc, R5,15,20; P < 0.01) were found. Significant negative correlations averaging -0.68 (R15,20,40) and -0.69 (R15,20,40) were demonstrated for Tsk and SBP and MAP, respectively. Increases in thigh Tsk (R5,15,20; P < 0.00001) and decreases in calf (R15,20,40,60; P < 0.00001) and chest (Tchest, R5,15,20,40; P < 0.00001) Tsk were found. Significant negative correlations averaging -0.67 (R5,15,20,40) and -0.71 (R20,40,60) were demonstrated for Tchest and SBP and MAP, respectively. Inverse relationships between various regional Ts and blood pressure and the increased R Tc suggest a vasodilatory response in the visceral organs and/or lower limbs leading to a pooling of blood and transient decreases in blood pressure by a reduced venous return, although not affecting stroke volume and cardiac output.

Role stress and strain among nondoctorally prepared undergraduate faculty in a school of nursing with a doctoral program

Initiation of a doctoral program within existing schools of nursing causes significant change in organizational structure and function. The role expectations of the current faculty change as well. The purpose of the qualitative study was to identify if role stress and strain are present in nondoctorally prepared undergraduate nursing faculty in a southern university school of nursing with a doctoral program. The design was a qualitative, open-ended interview. The primary research question was: Does the initiation of a doctoral program in a school of nursing impose role stress and strain on nondoctorally prepared faculty members? Academic educators will find our results interesting because faculty report that role stress and strain affect both their teaching and decisions to remain in academia. Use of these findings may contribute toward improved role relationships, better role performance, greater job satisfaction, and decreased job turnover.

Physiologic comparison and validation of Stairobic stepping with bench stepping

To compare the oxygen cost of submaximal exercise on the Stairobic stepping (SS) machine with bench stepping (BS), 12 healthy men and women (mean age 23 years) underwent six different five minute exercise bouts that were randomly assigned. Tests were conducted using standard open circuit calorimetry. SS at 40 and 60 st/min was equal to BS at 20 st/min and SS at 80 st/min was equal to BS at 30 st/min for VE and RER. VO2 was equal at 20 st/min (BS) and 60 st/min (SS), and 30 st/min (BS) and 80 st/min (SS). Stairobic MET (SM) displayed values over-estimated actual MET (AM) values at the two lowest SS rates and under-estimated the AM value at the highest SS rate. Forty-eight observations of the MET response of SS were conducted and analyzed (BMDP2R) in a forward stepping solution. The multiple regression equation calculated for AM was: AM = -0.567 + -0.012 (WT) + 0.063 (rate) + 0.612 (SM) with an adjusted R2 of 0.82 and a SEE of 0.90. The physiologic cost of BS was approximately equal to SS at two to three times the BS rate of stepping.

Cellular levels of messenger ribonucleic acids encoding vasoactive intestinal Peptide and gastrin-releasing Peptide in neurons of the suprachiasmatic nucleus exhibit distinct 24-hour rhythms

There is strong evidence supporting the view that the Suprachiasmatic nucleus (SCN) functions as a circadian clock; however, the neural and molecular events underlying SCN function remain unclear. A specific subpopulation of neurons within the ventrolateral aspect of the SCN that contains three peptides, vasoactive intestinal peptide (VIP), peptide histidine isoleucine (PHI) and gastrin-releasing peptide (GRP), play an important role in SCN function. VIP-containing neurons of the SCN receive synapses from photic projections, and co-injection of all three peptides mimics the phase-delaying effects of light on circadian activity rhythms. In principle, the signaling potential of a neuron containing several transmitters may be affected by the concentration ratio of co-released factors; hence, one mechanism by which VIP/PHI/GRP-containing neurons could influence SCN function is by changing the concentration ratio of these peptides throughout the light-dark cycle. The present study was performed to examine this possibility. Relative cellular levels of mRNA encoding both VIP/PHI and GRP were determined within the SCN every 4 h in rats housed in a 14 h light: 10 h dark cycle. Quantitative in situ hybridization revealed a statistically significant (P<0.005) 24-h profile of changes in VIP/PHI mRNA that peaked during the dark phase, and a significant (P<0.005) 24-h profile of changes in GRP mRNA that peaked during the light phase. These data support the interpretation that cellular levels of mRNAs encoding VIP/PHI and GRP within the SCN exhibit distinct profiles of changes throughout the light-dark cycle. Further, these findings are consistent with the hypothesis that the concentration ratio of VIP and PHI to GRP changes over the light-dark cycle, and that this may be an important mechanism by which circadian rhythms are generated or entrained.

Neuropeptide Y in the hypothalamus: effect on corticosterone and single-unit activity

The purpose of the present study was to determine whether neuropeptide Y (NPY) acts within the hypothalamic paraventricular nucleus (PVN) or the suprachiasmatic nucleus (SCN) to alter circulating levels of corticosterone and to evaluate the effects of NPY on the single-unit response of PVN and SCN neurons using the hypothalamic slice preparation. Blood levels of corticosterone were determined in groups of rats that received microinjections of NPY or saline (Sal) into the PVN or SCN. NPY injected into the PVN 4 h after light onset resulted in corticosterone levels of 13.15 +/- 2.18 (SE) micrograms/dl within 1 h, which were significantly higher than the corticosterone levels of 4.08 +/- 1.78 micrograms/dl seen in rats receiving Sal injections. In contrast, no significant differences were observed in circulating levels of corticosterone between groups of rats 1 or 4 h after NPY or Sal microinjection into the SCN. In the hypothalamic slice, NPY was found to produce primarily inhibitory responses in both SCN and PVN neurons. Forty-nine percent of the SCN units examined were inhibited. In addition, another 20% of the neurons tested in the SCN displayed excitation followed by more sustained inhibition. In the PVN, 45% of the units examined were inhibited by NPY, however, nearly 30% of the remaining neurons were significantly excited by NPY. In summary, NPY alters the electrical activity of both SCN and PVN neurons but appears to act only within the PVN to influence circulating levels of corticosterone. These and other data indicate that NPY acts as an important neurochemical messenger within several hypothalamic sites.