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.

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.

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.

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."

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.

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.

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.

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.

Competitive inhibition by lithium and hydrogen ions of the effect of calcium on the aggregation of rabbit platelets.

ADP-induced platelet aggregation and shape change were monitored optically in citrated rabbit platelet-rich plasma (PRP) diluted with isotonic salt solutions. Lithium (Li) produced a concentration-dependent reduction in the rate of platelet aggregation but had no discernible effect on the shape change which precedes aggregation. When PRP was pre-incubated with Li, the inhibitory effect of the ion was independent of the duration and temperature of the treatment. The inhibitory effect of Li also was observed in heparinized PRP or when 5-HT was used as the aggregation-inducing agent. When Li was combined with aggregation inhibitors which enhance platelet cyclic AMP content either by activating adenylate cyclase or by inhibiting phosphodiesterase, only additive effects were observed. The inhibitory effect of Li was opposed by added calcium. Kinetic evaluation of the interaction between Li and Ca indicated that their antagonism was competitive. Added calcium also displayed competitive antagonism toward the aggregation inhibiting effect of increased hydrogen ion concentration in the pH range between 6 and 8.

The effect of local anaesthetics and antiarrhythmic agents on the responses of rabbit platelete to ADP and thrombin.

Local anaesthetics and antiarrhythmic agents produced changes in responses of rabbit platelets to ADP and thrombin that varied with the agent and its concentration. In high concentrations all local anaesthetics decreased aggregation rates. At lower concentrations several local anaesthetics increased aggregation rates. Depending on the agonist and local anaesthetic, increases were produced at all or only at low or high agonist concentrations. Local anaesthetics failed to influence shape change except at concentrations much greater than those which inhibited aggregation. Inhibition of aggregation by procaine was potentiated by small organic anions suggesting effects at different sites on the platelet membrane. The inhibitory effect of local anaesthetics was decreased by increasing Ca. Kinetic analysis indicated different mechanisms for this Ca effect, i.e., predominantly competitive for procaine or lidocaine and predominantly non-competitive for tetracaine or ethyl lidocaine. Local anaesthetics may affect aggregation by modifying the participation of Ca in this process.

Effect of an impermeant arginine-modifying reagent on the responses of rabbit platelets to agonists.

The importance of surface arginyl residues in platelet aggregation was investigated by studying the effects of an impermeant arginine-modifying reagent, p-sulfonylphenylglyoxal (PSPG), on platelet responses to various agonists. Pretreatment of resuspended rabbit platelets with 2-15 mM PSPG resulted in complete inhibition of aggregation responses to ADP and 5-HT, and a concentration-dependent inhibition of the preceding shape change. Aggregation responses to thrombin also were inhibited in a concentration-dependent manner. The protective effects of antagonists of these three agonists (beta, gamma-methylene ATP for ADP, hirudin for thrombin and phentolamine for 5-HT) during pretreatment of platelets with PSPG indicated that intact arginine residues form part of the receptor sites for ADP and for thrombin. Arginine residues are not part of the 5-HT receptor site itself, but seem to be important for the maintenance of the functional integrity of this site.

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.

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.

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.

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.

Marital transitions. A child's perspective.

Despite a recent leveling off of the divorce rate, almost half of the children born in the last decade will experience the divorce of their parents, and most of these children will also experience the remarriage of their parents. Most children initially experience their parents' marital rearrangements as stressful; however, children's responses to their parents marital transitions are diverse. Whereas some exhibit remarkable resiliency and in the long term may actually be enhanced by coping with these transitions, others suffer sustained developmental delays or disruptions. Others appear to adapt well in the early stages of family reorganizations but show delayed effects that emerge at a later time, especially in adolescence. The long-term effects are related more to the child's developmental status, sex, and temperament; the qualities of the home and parenting environments; and to the resources and support systems available to the parents and child than they are to divorce or remarriage per se. In recent years, researchers have begun to move away from the view that single-parent and remarried families are atypical or pathogenic families and are focusing on the diversity of children's responses and to the factors that facilitate or disrupt the development and adjustment of children experiencing their parents' marital transitions.

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.

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.

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.

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.