Defining the Hoxb8 cell lineage during murine definitive hematopoiesis.

Previously, we have demonstrated that a subpopulation of microglia, known as Hoxb8 microglia, is derived from the Hoxb8 lineage during the second wave (E8.5) of yolk sac hematopoiesis, whereas canonical non-Hoxb8 microglia arise from the first wave (E7.5). Hoxb8 microglia have an ontogeny distinct from non-Hoxb8 microglia. Dysfunctional Hoxb8 microglia cause the acquisition of chronic anxiety and an obsessive-compulsive spectrum-like behavior, trichotillomania, in mice. The nature and fate of the progenitors generated during E8.5 yolk sac hematopoiesis have been controversial. Herein, we use the Hoxb8 cell lineage reporter to define the ontogeny of hematopoietic cells arising during the definitive waves of hematopoiesis initiated in the E8.5 yolk sac and aorta-gonad-mesonephros (AGM) region. Our murine cell lineage analysis shows that the Hoxb8 cell lineage reporter robustly marks erythromyeloid progenitors, hematopoietic stem cells and their progeny, particularly monocytes. Hoxb8 progenitors and microglia require Myb function, a hallmark transcription factor for definitive hematopoiesis, for propagation and maturation. During adulthood, all immune lineages and, interestingly, resident macrophages in only hematopoietic/lymphoid tissues are derived from Hoxb8 precursors. These results illustrate that the Hoxb8 lineage exclusively mirrors murine definitive hematopoiesis.

The natural history of insomnia: Does sleep extension differentiate between those that do and do not develop chronic insomnia?

According to the "3P model" of insomnia, the variable that mediates the transition from acute insomnia (AI) to chronic insomnia is "sleep extension" (the behavioural tendency to expand sleep opportunity to compensate for sleep loss). In the present analysis, we sought to evaluate how time in bed (TIB) varies relative to the new onset of AI and chronic insomnia. A total of 1,248 subjects were recruited as good sleepers (GS). Subjects were monitored over 1 year with sleep diaries. State transitions were defined, a priori, for AI, recovered from AI (AI-REC), and for chronic insomnia (AI-CI). Two additional groupings were added based on profiles that were unanticipated: subjects that exhibited persistent poor sleep following AI (AI-PPS [those that neither recovered or developed chronic insomnia]) and subjects that recovered from chronic insomnia (CI-REC). All the groups (GS, AI-REC, AI-CI, AI-PPS and CI-REC) were evaluated for TIB differences with longitudinal mixed effects models. Post hoc analyses for the percentage of the groups that were typed as TIB "restrictors, maintainers, and expanders" were conducted using longitudinal mixed effects models and contingency analyses. Significant differences for pre-post AI TIB were not detected for the insomnia groups. Trends were apparent for the AI-CI group, which suggested that minor increases in TIB occurred weeks before the declared onset of AI. Additionally, it was found that a significantly larger percentage of AI-CI subjects engaged in sleep extension (as compared to GS). The present data suggest that transition from AI to chronic insomnia does not appear to be initiated by sleep extension and the transition may occur before the elapse of 3 months of ≥3 nights of sleep continuity disturbance. Given these findings, it may be that the mismatch between sleep ability and sleep opportunity is perpetuated over time given the failure to "naturally" engage in sleep restriction (as opposed to sleep extension).

Intercostal Blocks with Liposomal Bupivacaine in Thoracic Surgery: A Retrospective Cohort Study.

OBJECTIVE: Assess the efficacy of adding liposomal bupivacaine (LB) to bupivacaine-containing intercostal nerve blocks (ICNBs) to improve analgesia and decrease opioid consumption and hospital length of stay compared with bupivacaine-only ICNBs. DESIGN: This retrospective, observational investigation compared pain intensity scores and cumulative opioid consumption within the first 72 postoperative hours in patients who received ICNBs with bupivacaine plus LB (LB group) versus bupivacaine only (control group) after minimally invasive anatomic pulmonary resection. LB was tested for noninferiority on pain scores and opioid consumption. If LB was noninferior, superiority of LB was tested on both outcomes. SETTING: Academic tertiary care medical center. PARTICIPANTS: Adult patients undergoing minimally invasive anatomic pulmonary resection. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: For the secondary analysis, hospital length of stay was compared through the Cox regression model. Of 396 patients, 178 (45%) received LB and 218 (55%) did not. The mean (standard deviation) pain score was three (one) in the LB group and three (one) in the control group, with a difference of -0.10 (97.5% confidence interval [-0.39 to 0.18]; p = 0.41). The mean (standard deviation) cumulative opioid consumption (intravenous morphine equivalents) was 198 (208) mg in the LB group and 195 (162) mg in the control group. Treatment effect in opioid consumption was estimated at a ratio of geometric mean of 0.94 (97.5% confidence interval [0.74-1.20]; p = 0.56). Pain control and opioid consumption were noninferior with LB but not superior. Hospital discharge was not different between groups. CONCLUSIONS: LB with bupivacaine in ICNBs did not demonstrate superior postoperative analgesia or affect the rate of hospital discharge.

Neural stem cell depletion and CNS developmental defects after enteroviral infection.

Coxsackieviruses are significant human pathogens causing myocarditis, meningitis, and encephalitis. We previously demonstrated the ability of coxsackievirus B3 (CVB3) to persist within the neonatal central nervous system (CNS) and to target neural stem cells. Given that CVB3 is a cytolytic virus and may therefore damage target cells, we characterized the potential reduction in neurogenesis within the developing brain and the subsequent developmental defects that occurred after the loss of these essential neural stem cells. Neonatal mice were inoculated with a recombinant CVB3 expressing eGFP (eGFP-CVB3), and alterations in neurogenesis and brain development were evaluated over time. We observed a reduction in proliferating cells in CNS neurogenic regions simultaneously with the presence of nestin(+) cells undergoing apoptosis. The size of the brain appeared smaller by histology, and a permanent decrease in brain wet weight was observed after eGFP-CVB3 infection. We also observed an inverse relationship between the amount of virus material and brain wet weight up to day 30 postinfection. In addition, signs of astrogliosis and a compaction of the cortical layers were observed at 90 days postinfection. Intriguingly, partial brain wet weight recovery was observed in mice treated with the antiviral drug ribavirin during the persistent stage of infection. Hence, long-term neurological sequelae might be expected after neonatal enteroviral infections, yet antiviral treatment initiated long after the end of acute infection might limit virus-mediated neuropathology.

Why Treat Insomnia?

"Why treat insomnia?" This question grows out of the perspective that insomnia is a symptom that should only receive targeted treatment when temporary relief is needed or until more comprehensive gains may be achieved with therapy for the parent or precipitating medical or psychiatric disorders. This perspective, however, is untenable given recent data regarding the prevalence, course, consequences, and costs of insomnia. Further, the emerging data that the treatment of insomnia may promote better medical and mental health (alone or in combination with other therapies) strongly suggests that the question is no longer "why treat insomnia," but rather "when isn't insomnia treatment indicated?" This perspective was recently catalyzed with the American College of Physicians' recommendation that chronic insomnia should be treated and that the first line treatment should be cognitive-behavioral therapy for insomnia (CBT-I).

Continuous Erector Spinae Plane Blocks for Adult Pectus Excavatum Repair.

Use of continuous erector spinae plane (ESP) blocks for pectus excavatum repair may be a valuable alternative to thoracic epidural placement. This report describes the successful use of bilateral ESP blocks in 2 patients with complex medical histories in which thoracic epidural placement was either contraindicated or unsuccessful. The benefits of continuous ESP blocks in this subset of patients include pain control with a focus on opioid sparing, early extubation, decreased atelectasis, improved mobilization and physical therapy, and decreased length of hospital stay.

The influence of abrupt increases in seawater pCO2 on plankton productivity in the subtropical North Pacific Ocean.

We conducted a series of experiments to examine short-term (2-5 days) effects of abrupt increases in the partial pressure of carbon dioxide (pCO2) in seawater on rates of primary and bacterial production at Station ALOHA (22°45' N, 158° W) in the North Pacific Subtropical Gyre (NPSG). The majority of experiments (8 of 10 total) displayed no response in rates of primary production (measured by 14C-bicarbonate assimilation; 14C-PP) under elevated pCO2 (~1100 µatm) compared to ambient pCO2 (~387 µatm). In 2 of 10 experiments, rates of 14C-PP decreased significantly (~43%) under elevated pCO2 treatments relative to controls. Similarly, no significant differences between treatments were observed in 6 of 7 experiments where bacterial production was measured via incorporation of 3H-leucine (3H-Leu), while in 1 experiment, rates of 3H-Leu incorporation measured in the dark (3H-LeuDark) increased more than 2-fold under high pCO2 conditions. We also examined photoperiod-length, depth-dependent (0-125 m) responses in rates of 14C-PP and 3H-Leu incorporation to abrupt pCO2 increases (to ~750 µatm). In the majority of these depth-resolved experiments (4 of 5 total), rates of 14C-PP demonstrated no consistent response to elevated pCO2. In 2 of 5 depth-resolved experiments, rates of 3H-LeuDark incorporation were lower (10% to 15%) under elevated pCO2 compared to controls. Our results revealed that rates of 14C-PP and bacterial production in this persistently oligotrophic habitat generally demonstrated no or weak responses to abrupt changes in pCO2. We postulate that any effects caused by changes in pCO2 may be masked or outweighed by the role that nutrient availability and temperature play in controlling metabolism in this ecosystem.

GABAergic inactivation of basolateral amygdala alters behavioral processes other than primary reward of ventral tegmental self-stimulation.

Although recent work on amygdalar function has concentrated on a role in fear and anxiety, a possible role in reward processes continues to be considered. This function may occur via anatomical connections between the basolateral amygdala (BLA) and the mesoaccumbens dopamine (DA) system (i.e., ventral tegmental area [VTA] to nucleus accumbens septi [NAS]), particularly at the level of the NAS. The current experiments investigated a possible role of the BLA in the reward of intracranial self-stimulation (ICSS) of the VTA. Rats were trained in either an autotitration ICSS task or a rate-frequency ICSS task. We examined the effect of intra-BLA injections of muscimol, a GABA(A) agonist which inhibits the firing of most neurons, on VTA ICSS in both behavioral procedures. The injections produced a pattern of behavioral change which, across the two tasks, was more consistent with a change in behavioral processes other than primary reward. Possible processes include cost/benefit analysis and incentive motivation.

Deformation of press-fitted metallic resurfacing cups. Part 2: Finite element simulation.

The deformation of metallic acetabular cups employed for metal-on-metal hip resurfacing procedures was considered theoretically using the finite element method in the present study, following on the experimental investigation reported in Part 1. Three representative cups, characterized by the cup wall thickness as thin, intermediate, and thick, were considered. For the intermediate cup, the effects of both the size and the diametral interference on the cup deformation were investigated. Both two-dimensional axisymmetric and three-dimensional finite element models were developed to examine the important parameters during and after the press-fit procedure, and in particular the deformation of the metallic cup. The theoretical prediction of the cup deformation was in reasonable agreement with the corresponding experimental measurement reported in Part 1. The most significant factor influencing the cup deformation was the cup wall thickness. Both the size and the diametral interference were also shown to influence the cup deformation. It is important to ensure that the cup deformation does not significantly affect the clearance designed and optimized for tribological performances of metal-on-metal hip resurfacing prostheses. Furthermore the contact parameters at the cup and bone interface associated with the press fit were also discussed.

Diversity and Activity of Communities Inhabiting Plastic Debris in the North Pacific Gyre.

Marine plastic debris has become a significant concern in ocean ecosystems worldwide. Little is known, however, about its influence on microbial community structure and function. In 2008, we surveyed microbial communities and metabolic activities in seawater and on plastic on an oceanographic expedition through the "great Pacific garbage patch." The concentration of plastic particles in surface seawater within different size classes (2 to 5 mm and >5 mm) ranged from 0.35 to 3.7 particles m-3 across sampling stations. These densities and the particle size distribution were consistent with previous values reported in the North Pacific Ocean. Net community oxygen production (NCP = gross primary production - community respiration) on plastic debris was positive and so net autotrophic, whereas NCP in bulk seawater was close to zero. Scanning electron microscopy and metagenomic sequencing of plastic-attached communities revealed the dominance of a few metazoan taxa and a diverse assemblage of photoautotrophic and heterotrophic protists and bacteria. Bryozoa, Cyanobacteria, Alphaproteobacteria, and Bacteroidetes dominated all plastic particles, regardless of particle size. Bacteria inhabiting plastic were taxonomically distinct from the surrounding picoplankton and appeared well adapted to a surface-associated lifestyle. Genes with significantly higher abundances among plastic-attached bacteria included che genes, secretion system genes, and nifH genes, suggesting enrichment for chemotaxis, frequent cell-to-cell interactions, and nitrogen fixation. In aggregate, our findings suggest that plastic debris forms a habitat for complex microbial assemblages that have lifestyles, metabolic pathways, and biogeochemical activities that are distinct from those of free-living planktonic microbial communities. IMPORTANCE Marine plastic debris is a growing concern that has captured the general public's attention. While the negative impacts of plastic debris on oceanic macrobiota, including mammals and birds, are well documented, little is known about its influence on smaller marine residents, including microbes that have key roles in ocean biogeochemistry. Our work provides a new perspective on microbial communities inhabiting microplastics that includes its effect on microbial biogeochemical activities and a description of the cross-domain communities inhabiting plastic particles. This study is among the first molecular ecology, plastic debris biota surveys in the North Pacific Subtropical Gyre. It has identified fundamental differences in the functional potential and taxonomic composition of plastic-associated microbes versus planktonic microbes found in the surrounding open-ocean habitat. Author Video: An author video summary of this article is available.

Cytokines, stressors, and clinical depression: augmented adaptation responses underlie depression pathogenesis.

By influencing the central nervous system, cytokines, which regulate immune function innately and adaptively, may play a key role in mediating depression-like neuro-behavioral changes. However, the similarity between cytokine and stressor-effects in animal models raises a question about the degree to which behavioral and neurochemical outcomes of cytokine challenge represent depressive disorder per se. The present review attempts to illustrate the degree of overlap between cytokines and stressors with respect to their effects on neurochemistry and behavior in animal models. The review also shows how short-term effects of cytokine exposure in typical animals may be discerned from characteristics that might otherwise be described as depression-like. By comparing outcomes of immune challenge in typical rodent strains (e.g., Sprague-Dawley [SD], Wistar) and an accepted animal model of depression (e.g., Fawn Hooded [FH] rodent strain), differences between short-term effects of cytokines and depression-like characteristics in rodents are demonstrated. Additionally, because it is known that preexisting vulnerability to depression may affect outcomes of immune challenge, we further compare immunological, biochemical and behavioral effects of cytokines between SD and FH rodent strains. Interestingly, the acute neurochemical and behavioral effects of the cytokine interleukin 1alpha (IL-1alpha) reveal stressor-like responses during behavioral habituation in both strains, though this appears to a stronger degree in FH animals. Further, the subacute response to IL-1alpha vastly differed between strains, indicating differences in adaptive mechanisms. Thus, stressor-like effects of immune challenge, particularly in FH animals, provide validation for recent "cross-sensitization" models of depression pathogenesis that incorporate immune factors.

Aphakic bullous keratopathy treated with prosthokeratoplasty. An analysis of 34 consecutive cases.

Thirty-four eyes with advanced aphakic bullous keratopathy were treated with the Cardona keratoprosthesis as a primary procedure. There were three extrusions (9%), two of which were associated with infections; two other conditions were worsened (6%) as a result of a late permanent vitreous hemorrhage or possibly an infection. Twenty-eight eyes (82%) showed a notable improvement during follow-up periods that ranged from 6 to 72 months. The advantages and limitations of this technique are compared to those of penetrating keratoplasty.

In vivo measurement of posterior chamber intraocular lens decentration and tilt.

We report what to our knowledge is the first extensive in vivo clinical study of intraocular lens decentration and tilt. Measurements of posterior chamber intraocular lenses, all implanted by the same surgeon in 89 eyes, showed that decentration and tilt consistently differed between right and left eyes. Lenses tended to decenter superotemporally and tilt with their superonasal edges tipped forward. Decentration magnitude relative to the cornea light reflex axis and line of sight averaged 0.64 mm, with decentration increasing slightly with increased axial length. Average tilt was 6.75 degrees, and the average tilt-induced astigmatism was 0.27 diopter. Tilt magnitude decreased with increased axial length, as did tilt-induced astigmatism and plus sphere.

Improved detection of persistent foot-and-mouth disease infection in cattle by the polymerase chain reaction.

Persistent foot-and-mouth disease (FMD) infection of cattle was established by exposure to infected pigs. Oesophageal-pharyngeal fluid samples collected ante-mortem and tissue samples obtained post-mortem were tested for virus by conventional means and for viral RNA by the polymerase chain reaction (PCR). The results showed that the PCR was superior for detecting the carrier state in tissue samples. A high neutralising activity in tissues probably influenced the yields of virus obtained by infectivity assay.

Serological diagnosis of chlamydial abortion in sheep and goats: comparison of the complement fixation test and an enzyme-linked immunosorbent assay employing solubilised proteins as antigen.

A new ELISA for antibodies against chlamydial abortion of ewes which uses detergent solubilised proteins (dsp) of Chlamydia psittaci as antigen (Anderson, I.E., Herring, A.J., Jones, G.E., Low, J.C., Greig, A., 1995. Development and evaluation of an indirect ELISA to detect antibodies to abortion strains of Chlamydia psittaci in sheep sera. Vet. Microbiol., 43, pp. 1-12] was compared with the complement fixation test (CFT) in screening 1000 ovine and caprine sera obtained from selected flocks/herds ('flocks') and submitted to a veterinary diagnostic laboratory. Fifteen of the 17 'flocks' had a history of abortion while the remaining two did not and were classified as 'negative flocks'. Infection with Chlamydia was confirmed during the study period in five 'flocks' using direct immunofluorescence and the modified Ziehl Neelsen stain on pathological material. The dspELISA and CFT identified 37 and 45 positive sera on 158 samples tested from these 'flocks'. Chlamydia antibodies were not detected in one of the two negative flocks, in two other flocks where the cause of abortion was undetermined and in three flocks in which the causes of abortion were diagnosed as Listeriosis and/or Salmonellosis. One of the 'negative flocks' yielded two positive reactors by CFT and five by dspELISA, suggesting infection with a cross-reactive subtype of C. pecorum. Of the five 'flocks' in which a definitive diagnosis from pathological material was not possible, four were positive by both serological tests, suggesting that the abortions were due to Chlamydia. The fifth flock, though negative by dspELISA and marginally positive in two samples by CFT, had experienced confirmed chlamydial abortions in previous lambing seasons, but culling and tetracycline treatment have prevented further abortions in the study period. Overall, the proportions of samples positive by CFT and dspELISA were similar (9.1% and 8.8%). These studies confirmed the value of the dspELISA as a screening test for chlamydial abortion. Furthermore, the dspELISA compared to the CFT is easier to perform, does not require reagent titration at each testing and uses automated assessment of results.

Multiple myeloma presenting as vortex crystalline keratopathy and complicated by endocapsular hematoma.

The crystalline keratopathy of multiple myeloma may involve the corneal epithelium, but has not previously been described in a vortex epithelial distribution. Endocapsular hematomas have been described in the period immediately after extracapsular cataract extraction, but not later on or in association with systemic disease. We report a pseudophakic patient who developed a vortex epithelial crystalline keratopathy as a presenting sign of multiple myeloma, and who subsequently developed a spontaneous endocapsular hematoma.

The use of fluorescein-conjugated monoclonal antibodies, cell culture and transmission electron microscopy to detect Chlamydia psittaci and associated lesions in experimentally infected mice.

An immunofluorescence test based on a monoclonal antibody (mAb) was used to demonstrate chlamydiae in formalin-fixed and paraffin wax-embedded tissues from 10 adult mice experimentally infected by the oral route with Chlamydia psittaci isolated from the fetal membranes of an aborted ovine fetus. Samples of lung, jejunum and spleen were examined by bright-field microscopy, immunofluorescence and transmission electron microscopy, and were cultured for chlamydia in McCoy cells. These tissues were compared with those of two control mice. All infected mice had splenic hyperplasia and two had pneumonia. The lung appeared to be the target organ for C. psittaci administered by the oral route. Chlamydiae were identified in the lungs of five mice by immunofluorescence, bright-field and transmission electron microscopy. Chlamydiae were cultured from the jejunum of two mice and the spleen of one, but could not be identified at these sites by other methods. Immunofluorescence with an anti-chlamydia mAb was useful for detecting chlamydial antigen in formalin-fixed paraffin wax-embedded samples.

Preparation and use of a monoclonal antibody to detect Chlamydia psittaci antigen in paraffin-embedded tissue sections.

A murine monoclonal antibody prepared against an ovine abortion isolate of Chlamydia psittaci (A22/Teramo) revealed specific binding to a 57 kDa chlamydial antigen in immunoblotting studies. The monoclonal antibody was able to detect intracytoplasmic chlamydial inclusions and scattered elementary bodies in infected McCoy cell culture, and on formalin-fixed paraffin-embedded tissue sections both from experimentally infected mice and from fetal membranes of cases of ovine enzootic abortion.

Prostatic cancer: some epidemiological features.

Prostatic cancer is a frequent tumour in old men. The disease is very common in North America, particularly among Blacks, and in Scandinavia, while it is currently rare in Asian countries. Both morbidity and mortality rates have increased in most areas in recent years, the rate of increase being greatest in populations where the risk has hitherto been low. "Latent" (microscopic) prostatic cancer is much commoner than overt clinical prostatic cancer and, in contrast to the latter, the prevalence is similar in a wide spectrum of countries and ethnic groups. Detection of these latent tumours is dependent on medical care variables. The relationships between tumor development, latency and progression are not understood. It may be useful to consider "latent" prostatic cancer as a separate entity in future classifications and epidemiological research. Hormonal, sexual, dietary, chemical and genetic factors have been implicated in the aetiology although the mechanisms by which they act and the relationships between these factors are not known. As a high fat diet has been found to increase risk in case-control studies, a plausible sequence of events would be a fat-induced change of hormone profile with increased uptake by the prostate of male sex hormones leading to carcinoma--as in the rat. The evidence is however by no means entirely consistent and should be explored further in studies of the US Black and White populations, populations with age-standardized incidence rates in the order of 100 and 50 per 100,000 per annum respectively. If it be accepted that the factors leading to latent carcinoma of prostate are evenly distributed throughout the world, then studies directed at uncovering the agents responsible for progression from latent to clinically invasive state could be rewarding. Such studies would need to be large, prospective in nature and would require a high frequency of autopsy of cohort members to ascertain whether the prostate was cancer free or not. Prevention is not feasible on the basis of current knowledge and further inquiry regarding the aetiopathogenesis of prostatic cancer is needed before preventive approaches can be envisaged.

Polyurethane heart valve durability: effects of leaflet thickness and material.

A flexible trileaflet polyurethane valve has been made by dip-moulding leaflets directly onto an injection-moulded frame. The durability of this value is, in part, determined by the thickness of its leaflets. Leaflet thickness is also a major determinant of hydrodynamic function. This study examines valves (n = 31) with leaflets made of a polyetherurethane (PEU, n = 22) or a polyetherurethaneurea (PEUE, n = 9), of varying thickness distributions. The valves were subjected to accelerated fatigue test at 37 degrees C and failure monitored. Leaflet thicknesses ranged from 60 to 200 microns. PEU leaflet thickness bore no relationship to durability, which was less than 400 million cycles. PEUE valves, in contrast, exceeded 800 million cycles. Durability in PEUE valves was directly related to leaflet thickness (r = 0.93, p < 0.001), with good durability achieved with median leaflet thicknesses of approximately 150 microns. Thus polyurethane valves can be made with good hydrodynamic properties and with sufficient durability to consider potential clinical use.