Allergic asthma is a chronic inflammatory disease and despite the introduction of potent and effective drugs, the prevalence has increased substantially over the past few decades. The explanation that has attracted the most attention is the 'hygiene hypothesis', which suggests that the increase in allergic diseases is caused by a cleaner environment and fewer childhood infections. Indeed, certain mycobacterial strains can cause a shift from T-helper cell 2 (Th2) to Th1 immune responses, which may subsequently prevent the development of allergy in mice. Although the reconstitution of the balance between Th1 and Th2 is an attractive theory, it is unlikely to explain the whole story, as autoimmune diseases characterized by Th1 responses can also benefit from treatment with mycobacteria and their prevalence has also increased in parallel to allergies. Here we show that treatment of mice with SRP299, a killed Mycobacterium vaccae-suspension, gives rise to allergen-specific CD4+CD45RB(Lo) regulatory T cells, which confer protection against airway inflammation. This specific inhibition was mediated through interleukin-10 (IL-10) and transforming growth factor-beta (TGF-beta), as antibodies against IL-10 and TGF-beta completely reversed the inhibitory effect of CD4+CD45RB(Lo) T cells. Thus, regulatory T cells generated by mycobacteria treatment may have an essential role in restoring the balance of the immune system to prevent and treat allergic diseases.

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is an emerging nosocomial pathogen. Little is known about its risk factors or mortality. We performed a case-case-control study to assess the risks for CRKP isolation and a retrospective cohort study to assess mortality in three groups of hospitalized adults: (i) patients from whom CRKP was isolated, (ii) patients from whom carbapenem-susceptible Klebsiella spp. (CSKS) were isolated, and (iii) controls from whom no Klebsiella spp. were isolated. After adjustment for length of stay (LOS), the demographics, comorbidities, and exposures of each case group were compared with those of the controls. Significant covariates were incorporated into LOS-adjusted multivariable models. In the mortality study, we evaluated the effect of CRKP on in-hospital death. There were 48 patients with CRKP isolation (21 died [44%]), 56 patients with CSKS isolation (7 died [12.5%]), and 59 controls (1 died [2%]). Independent risk factors for CRKP isolation were poor functional status (odds ratio [OR], 15.4; 95% confidence interval [CI], 4.0 to 58.6; P < 0.001); intensive care unit (ICU) stay (OR, 17.4; 95% CI, 1.5 to 201.9; P = 0.02); and receipt of antibiotics (OR, 4.4; 95% CI, 1.0 to 19.2; P = 0.05), particularly fluoroquinolones (OR, 7.2; 95% CI, 1.1 to 49.4; P = 0.04). CRKP was independently associated with death when patients with CRKP were compared with patients with CSKS (OR, 5.4; 95% CI, 1.7 to 17.1; P = 0.005) and with controls (OR, 6.7; 95% CI, 2.4 to 18.8; P < 0.001). After adjustment for the severity of illness, CRKP isolation remained predictive of death, albeit with a lower OR (for the CRKP group versus the CSKS group, OR, 3.9; 95% CI, 1.1 to 13.6; and P = 0.03; for the CRKP group versus the controls, OR, 5.0; 95% CI, 1.7 to 14.8; and P = 0.004). CRKP affects patients with poor functional status, an ICU stay, and antibiotic exposure and is an independent predictor of death.

OBJECTIVE

In this report the authors describe the epidemiology of craniopharyngioma.

METHODS

The incidence of craniopharyngioma in the United States was estimated from two population-based cancer registries that include brain tumors of benign and borderline malignancy: the Central Brain Tumor Registry of the United States (CBTRUS) and the Los Angeles county Cancer Surveillance Program. Information on additional pediatric tumors was available from the Greater Delaware Valley Pediatric Tumor Registry (GDVPTR). The overall incidence of craniopharyngioma was 0.13 per 100,000 person years and did not vary by gender or race. A bimodal distribution by age was noted with peak incidence rates in children (aged 5-14 years) and among older adults (aged 65-74 years in CBTRUS and 50-74 years in Los Angeles county). Survival information was available from GDVPTR and the National Cancer Data Base (NCDB), a hospital-based reporting system. In the NCDB, the 5-year survival rate was 80% and decreased with older age at diagnosis. Survival is higher among children and has improved in recent years.

CONCLUSIONS

Craniopharyngioma is a rare brain tumor of uncertain behavior that occurs at a rate of 1.3 per million person years. Approximately 338 cases of this disease are expected to occur annually in the United States, with 96 occurring in children from 0 to 14 years of age.

BACKGROUND

Following the reintroduction of metal-on-metal articulating surfaces for total hip arthroplasty in Europe in 1988, we developed a surface arthroplasty prosthetic system using a metal-on-metal articulation. The present study describes the clinical and radiographic results of the first 400 hips treated with metal-on-metal hybrid surface arthroplasties at an average follow-up of three and a half years.

METHODS

Between November 1996 and November 2000, 400 metal-on-metal hybrid surface arthroplasties were performed in 355 patients. All femoral head components were cemented, but only fifty-nine of the short metaphyseal stems were cemented. The patients had an average age of forty-eight years, 73% were men, and 66% had a diagnosis of osteoarthritis. Clinical and radiographic follow-up were performed at three months postoperatively and yearly thereafter.

RESULTS

The majority of the patients returned to a high level of activity, including sports, and 54% had activity scores of >7 on the University of California at <em>Los</em> Angeles activity assessment system. Kaplan-Meier survivorship curves demonstrated that the rate of survival of the components at four years was 94.4%. For patients with a surface arthroplasty risk index score of >3, the rate of survival of the components at four years was 89% compared with a rate of 97% for those with a score of </=3. The patients with a higher risk index were 4.2 times more likely to undergo revision to a total hip replacement at four years. Twelve hips (3%) had a revision to a total hip replacement. Seven of the twelve hips were revised because of loosening of the femoral component, and three were revised because of a femoral neck fracture. Substantial radiolucencies were seen around sixteen uncemented metaphyseal femoral stems. No femoral radiolucencies were observed among the hips in which the metaphyseal stem was cemented. The most important risk factors for femoral component loosening and substantial stem radiolucencies were large femoral head cysts (p = 0.029), patient height (p = 0.032), female gender (p = 0.005), and smaller component size in male patients (p = 0.005).

CONCLUSIONS

The preliminary experience with this hybrid metal-on-metal bearing is encouraging. Optimal femoral bone preparation and component fixation are critical to improving durability. The metal-on-metal hybrid surface arthroplasty is easily revised to a standard femoral component if necessary.

METHODS

Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.

The majority of BRCA1-associated breast cancers are basal cell-like, which is associated with a poor outcome. Using a spontaneous mouse mammary tumor model, we show that platinum compounds, which generate DNA breaks during the repair process, are more effective than doxorubicin in Brca1/p53-mutated tumors. At 0.5 mg/kg of daily cisplatin treatment, 80% primary tumors (n = 8) show complete pathologic response. At greater dosages, 100% show complete response (n = 19). However, after 2 to 3 months of complete remission following platinum treatment, tumors relapse and become refractory to successive rounds of treatment. Approximately 3.8% to 8.0% (mean, 5.9%) of tumor cells express the normal mammary stem cell markers, CD29(hi)24(med), and these cells are tumorigenic, whereas CD29(med)24(-/lo) and CD29(med)24(hi) cells have diminished tumorigenicity or are nontumorigenic, respectively. In partially platinum-responsive primary transplants, 6.6% to 11.0% (mean, 8.8%) tumor cells are CD29(hi)24(med); these populations significantly increase to 16.5% to 29.2% (mean, 22.8%; P < 0.05) in platinum-refractory secondary tumor transplants. Further, refractory tumor cells have greater colony-forming ability than the primary transplant-derived cells in the presence of cisplatin. Expression of a normal stem cell marker, Nanog, is decreased in the CD29(hi)24(med) populations in the secondary transplants. Top2A expression is also down-regulated in secondary drug-resistant tumor populations and, in one case, was accompanied by genomic deletion of Top2A. These studies identify distinct cancer cell populations for therapeutic targeting in breast cancer and implicate clonal evolution and expansion of cancer stem-like cells as a potential cause of chemoresistance.

BACKGROUND

Selective serotonin reuptake inhibitors are widely prescribed for children with autism spectrum disorders.

OBJECTIVE

To determine the efficacy and safety of citalopram hydrobromide therapy for repetitive behavior in children with autism spectrum disorders.

METHODS

National Institutes of Health-sponsored randomized controlled trial.

METHODS

Six academic centers, including Mount Sinai School of Medicine, North Shore-Long Island Jewish Health System, University of North Carolina at Chapel Hill, University of California at Los Angeles, Yale University, and Dartmouth Medical School.

METHODS

One hundred forty-nine volunteers 5 to 17 years old (mean [SD] age, 9.4 [3.1] years) were randomized to receive citalopram (n = 73) or placebo (n = 76). Participants had autistic spectrum disorders, Asperger disorder, or pervasive developmental disorder, not otherwise specified; had illness severity ratings of at least moderate on the Clinical Global Impressions, Severity of Illness Scale; and scored at least moderate on compulsive behaviors measured with the Children's Yale-Brown Obsessive Compulsive Scales modified for pervasive developmental disorders.

METHODS

Twelve weeks of citalopram hydrobromide (10 mg/5 mL) or placebo. The mean (SD) maximum dosage of citalopram hydrobromide was 16.5 (6.5) mg/d by mouth (maximum, 20 mg/d).

METHODS

Positive response was defined by a score of much improved or very much improved on the Clinical Global Impressions, Improvement subscale. An important secondary outcome was the score on the Children's Yale-Brown Obsessive Compulsive Scales modified for pervasive developmental disorders. Adverse events were systematically elicited using the Safety Monitoring Uniform Report Form.

RESULTS

There was no significant difference in the rate of positive response on the Clinical Global Impressions, Improvement subscale between the citalopram-treated group (32.9%) and the placebo group (34.2%) (relative risk, 0.96; 95% confidence interval, 0.61-1.51; P>> .99). There was no difference in score reduction on the Children's Yale-Brown Obsessive Compulsive Scales modified for pervasive developmental disorders from baseline (mean [SD], -2.0 [3.4] points for the citalopram-treated group and -1.9 [2.5] points for the placebo group; P = .81). Citalopram use was significantly more likely to be associated with adverse events, particularly increased energy level, impulsiveness, decreased concentration, hyperactivity, stereotypy, diarrhea, insomnia, and dry skin or pruritus.

CONCLUSIONS

Results of this trial do not support the use of citalopram for the treatment of repetitive behavior in children and adolescents with autism spectrum disorders. Trial Registration clinicaltrials.gov Identifier: NCT00086645.

Treatment of human artery wall cells with apolipoprotein A-I (apoA-I), but not apoA-II, with an apoA-I peptide mimetic, or with high density lipoprotein (HDL), or paraoxonase, rendered the cells unable to oxidize low density lipoprotein (LDL). Human aortic wall cells were found to contain 12-lipoxygenase (12-LO) protein. Transfection of the cells with antisense to 12-LO (but not sense) eliminated the 12-LO protein and prevented LDL-induced monocyte chemotactic activity. Addition of 13(S)-hydroperoxyoctadecadienoic acid [13(S)-HPODE] and 15(S)-hydroperoxyeicosatetraenoic acid [15(S)-HPETE] dramatically enhanced the nonenzymatic oxidation of both 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (PAPC) and cholesteryl linoleate. On a molar basis 13(S)-HPODE and 15(S)-HPETE were approximately two orders of magnitude greater in potency than hydrogen peroxide in causing the formation of biologically active oxidized phospholipids (m/z 594, 610, and 828) from PAPC. Purified paraoxonase inhibited the biologic activity of these oxidized phospholipids. HDL from 10 of 10 normolipidemic patients with coronary artery disease, who were neither diabetic nor receiving hypolipidemic medications, failed to inhibit LDL oxidation by artery wall cells and failed to inhibit the biologic activity of oxidized PAPC, whereas HDL from 10 of 10 age- and sex-matched control subjects did. We conclude that a) mildly oxidized LDL is formed in three steps, one of which involves 12-LO and each of which can be inhibited by normal HDL, and b) HDL from at least some coronary artery disease patients with normal blood lipid levels is defective both in its ability to prevent LDL oxidation by artery wall cells and in its ability to inhibit the biologic activity of oxidized PAPC.

Neonatal colonization by microbes, which begins immediately after birth, is influenced by gestational age and the mother's microbiota and is modified by exposure to antibiotics. In neonates, prolonged duration of antibiotic therapy is associated with increased risk of late-onset sepsis (LOS), a disorder controlled by neutrophils. A role for the microbiota in regulating neutrophil development and susceptibility to sepsis in the neonate remains unclear. We exposed pregnant mouse dams to antibiotics in drinking water to limit transfer of maternal microbes to the neonates. Antibiotic exposure of dams decreased the total number and composition of microbes in the intestine of the neonates. This was associated with decreased numbers of circulating and bone marrow neutrophils and granulocyte/macrophage-restricted progenitor cells in the bone marrow of antibiotic-treated and germ-free neonates. Antibiotic exposure of dams reduced the number of interleukin-17 (IL-17)-producing cells in the intestine and production of granulocyte colony-stimulating factor (G-CSF). Granulocytopenia was associated with impaired host defense and increased susceptibility to Escherichia coli K1 and Klebsiella pneumoniae sepsis in antibiotic-treated neonates, which could be partially reversed by administration of G-CSF. Transfer of a normal microbiota into antibiotic-treated neonates induced IL-17 production by group 3 innate lymphoid cells (ILCs) in the intestine, increasing plasma G-CSF levels and neutrophil numbers in a Toll-like receptor 4 (TLR4)- and myeloid differentiation factor 88 (MyD88)-dependent manner and restored IL-17-dependent resistance to sepsis. Specific depletion of ILCs prevented IL-17- and G-CSF-dependent granulocytosis and resistance to sepsis. These data support a role for the intestinal microbiota in regulation of granulocytosis, neutrophil homeostasis and host resistance to sepsis in neonates.

Social stress is associated with altered immunity and higher incidence of anxiety-related disorders. Repeated social defeat (RSD) is a murine stressor that primes peripheral myeloid cells, activates microglia, and induces anxiety-like behavior. Here we show that RSD-induced anxiety-like behavior corresponded with an exposure-dependent increase in circulating monocytes (CD11b(+)/SSC(lo)/Ly6C(hi)) and brain macrophages (CD11b(+)/SSC(lo)/CD45(hi)). Moreover, RSD-induced anxiety-like behavior corresponded with brain region-dependent cytokine and chemokine responses involved with myeloid cell recruitment. Next, LysM-GFP(+) and GFP(+) bone marrow (BM)-chimeric mice were used to determine the neuroanatomical distribution of peripheral myeloid cells recruited to the brain during RSD. LysM-GFP(+) mice showed that RSD increased recruitment of GFP(+) macrophages to the brain and increased their presence within the perivascular space (PVS). In addition, RSD promoted recruitment of GFP(+) macrophages into the PVS and parenchyma of the prefrontal cortex, amygdala, and hippocampus of GFP(+) BM-chimeric mice. Furthermore, mice deficient in chemokine receptors associated with monocyte trafficking [chemokine receptor-2 knockout (CCR2(KO)) or fractalkine receptor knockout (CX3CR1(KO))] failed to recruit macrophages to the brain and did not develop anxiety-like behavior following RSD. Last, RSD-induced macrophage trafficking was prevented in BM-chimeric mice generated with CCR2(KO) or CX3CR1(KO) donor cells. These findings indicate that monocyte recruitment to the brain in response to social stress represents a novel cellular mechanism that contributes to the development of anxiety.

We studied prospectively the quantitative relation of circulating endotoxin (lipooligosaccharides [LOSs]) and the development of multiple organ failure and death in 45 consecutively admitted patients with bacteriologically verified systemic meningococcal disease (SMD). A plasma LOS level of greater than 700 ng/L correlated with development of severe septic shock (P less than .0001), adult respiratory distress syndrome (P = .0035), a pathologically elevated serum creatinine level (P less than .0001), or death as a consequence of multiple organ failure (P = .0002). Initial plasma LOS levels of less than 25, 25-700, 700-10,000, and greater than 10,000 ng/L were associated with 0%, 14%, 27%, and 86% fatality, respectively. The LOS half-life after initiation of antibiotic therapy was 1-3 h. Increasing plasma LOS levels were never seen. These observations suggest that LOS quantitation using the limulus amebocyte lysate assay with a chromogenic substrate gives important progsnotic information and may provide new insight concerning pathophysiological aspects of SMD.

The development of measures for assessing oral health status is essential to the evolution and maturation of a scientific knowledge base in geriatric dentistry. The literature suggests a high prevalence of dental diseases in older adults, yet valid and reliable instruments to assess the impact of oral diseases on older individuals or populations are lacking. This paper describes the rationale for and the development of the Geriatric Oral Health Assessment Index (GOHAI), a self-reported measure designed to assess the oral health problems of older adults. Following a review of the literature and consultation with health care providers and patients, a pilot instrument was developed. The GOHAI was initially tested on a convenience sample of 87 older adults. A revised instrument was then administered to a sample of 1755 Medicare recipients in Los Angeles County. The GOHAI demonstrated a high level of internal consistency and reliability as measured by a Cronbach's alpha of 0.79. Associations of the GOHAI with a single-item rating of dental health and with clinical and sociodemographic supported the construct validity of the index. Having fewer teeth, wearing a removable denture and perceiving the need for dental treatment were significantly related to a worse (lower) GOHAI score. Respondents who were white, well educated, and with a higher annual household income were more likely to have a high GOHAI score, indicating fewer dental problems. Additional applications of the GOHAI are necessary to further evaluate the instrument's validity and reliability, and to establish population norms of oral health in older adult populations as measured by the GOHAI.

Activation of the 5-lipoxygenase (5-LO) pathway leads to the biosynthesis of proinflammatory leukotriene lipid mediators. Genetic studies have associated 5-LO and its accessory protein, 5-LO-activating protein, with cardiovascular disease, myocardial infarction and stroke. Here we show that 5-LO-positive macrophages localize to the adventitia of diseased mouse and human arteries in areas of neoangiogenesis and that these cells constitute a main component of aortic aneurysms induced by an atherogenic diet containing cholate in mice deficient in apolipoprotein E. 5-LO deficiency markedly attenuates the formation of these aneurysms and is associated with reduced matrix metalloproteinase-2 activity and diminished plasma macrophage inflammatory protein-1alpha (MIP-1alpha; also called CCL3), but only minimally affects the formation of lipid-rich lesions. The leukotriene LTD(4) strongly stimulates expression of MIP-1alpha in macrophages and MIP-2 (also called CXCL2) in endothelial cells. These data link the 5-LO pathway to hyperlipidemia-dependent inflammation of the arterial wall and to pathogenesis of aortic aneurysms through a potential chemokine intermediary route.

BACKGROUND

Early intensive behavioral and developmental interventions for young children with autism spectrum disorders (ASDs) may enhance developmental outcomes.

OBJECTIVE

To systematically review evidence regarding such interventions for children aged 12 and younger with ASDs.

METHODS

We searched Medline, PsycINFO, and ERIC (Education Resources Information Center) from 2000 to May 2010. Two reviewers independently assessed studies against predetermined inclusion/exclusion criteria. Two reviewers independently extracted data regarding participant and intervention characteristics, assessment techniques, and outcomes and assigned overall quality and strength-of-evidence ratings using predetermined criteria.

RESULTS

Thirty-four unique studies met inclusion criteria. Seventeen studies were case series; 2 were randomized controlled trials. We rated 1 study as good quality, 10 as fair quality, and 23 as poor quality. The strength of the evidence overall ranged from insufficient to low. Studies of University of California Los Angeles/Lovaas-based interventions and variants reported clinically significant gains in language and cognitive skills in some children, as did 1 randomized controlled trial of an early intensive developmental intervention approach (the Early Start Denver Model). Specific parent-training approaches yielded gains in short-term language function and some challenging behaviors. Data suggest that subgroups of children displayed more prominent gains across studies, but participant characteristics associated with greater gains are not well understood.

CONCLUSIONS

Studies of Lovaas-based approaches and early intensive behavioral intervention variants and the Early Start Denver Model resulted in some improvements in cognitive performance, language skills, and adaptive behavior skills in some young children with ASDs, although the literature is limited by methodologic concerns.

Using fluorescent HLA-A*0201 tetramers containing the immunodominant Melan-A/MART-1 (Melan-A) tumor-associated antigen (Ag), we previously observed that metastatic lymph nodes of melanoma patients contain high numbers of Ag-experienced Melan-A-specific cytolytic T lymphocytes (CTLs). In this paper, we enumerated and characterized ex vivo Melan-A-specific cells in peripheral blood samples from both melanoma patients and healthy individuals. High frequencies >>/=1 in 2,500 CD8(+) T cells) of Melan-A-specific cells were found in 10 out of 13 patients, and, surprisingly, in 6 out of 10 healthy individuals. Virtually all Melan-A-specific cells from 6 out of 6 healthy individuals and from 7 out of 10 patients displayed a naive CD45RA(hi)/RO(-) phenotype, whereas variable proportions of Ag-experienced CD45RA(lo)/RO(+) Melan-A-specific cells were observed in the remaining 3 patients. In contrast, ex vivo influenza matrix-specific CTLs from all individuals exhibited a CD45RA(lo)/RO(+) memory phenotype as expected. Ag specificity of tetramer-sorted A2/Melan-A(+) cells from healthy individuals was confirmed after mitogen-driven expansion. Likewise, functional limiting dilution analysis and interferon gamma ELISPOT assays independently confirmed that most of the Melan-A-specific cells were not Ag experienced. Thus, it appears that high frequencies of naive Melan-A-specific CD8(+) T cells can be found in a large proportion of HLA-A*0201(+) individuals. Furthermore, as demonstrated for one patient followed over time, dramatic phenotype changes of circulating Melan-A-specific cells can occur in vivo.

Egr2 is a transcription factor required for peripheral nerve myelination in rodents, and mutations in Egr2 are associated with congenital hypomyelinating neuropathy (CHN) in humans. To further study its role in myelination, we generated mice harboring a hypomorphic Egr2 allele (Egr2Lo) that survive for up to 3 weeks postnatally, a period of active myelination in rodents. These Egr2Lo/Lo mice provided the opportunity to study the molecular effects of Egr2 deficiency on Schwann cell biology, an analysis that was not possible previously, because of the perinatal lethality of Egr2-null mice. Egr2Lo/Lo mice phenocopy CHN, as evidenced by the severe hypomyelination and increased numbers of proliferating Schwann cells of the peripheral nerves. Comparison of sciatic nerve gene expression profiles during development and after crush injury with those of Egr2Lo/Lo Schwann cells revealed that they are developmentally arrested, with down-regulation of myelination-related genes and up-regulation of genes associated with immature and promyelinating Schwann cells. One of the abnormally elevated genes in Egr2Lo/Lo Schwann cells, Sox2, encodes a transcription factor that is crucial for maintenance of neural stem cell pluripotency. Wild-type Schwann cells infected with Sox2 adenovirus or lentivirus inhibited expression of myelination-associated genes (e.g., myelin protein zero; Mpz), and failed to myelinate axons in vitro, but had an enhanced proliferative response to beta-neuregulin. The characterization of a mouse model of CHN has provided insight into Schwann cell differentiation and allowed the identification of Sox2 as a negative regulator of myelination.

Catecholamines are important regulators of homeostasis, yet their functions in hematopoiesis are poorly understood. Here we report that immature human CD34+ cells dynamically expressed dopamine and beta2-adrenergic receptors, with higher expression in the primitive CD34+CD38(lo) population. The myeloid cytokines G-CSF and GM-CSF upregulated neuronal receptor expression on immature CD34+ cells. Treatment with neurotransmitters increased the motility, proliferation and colony formation of human progenitor cells, correlating with increased polarity, expression of the metalloproteinase MT1-MMP and activity of the metalloproteinase MMP-2. Treatment with catecholamines enhanced human CD34+ cell engraftment of NOD-SCID mice through Wnt signaling activation and increased cell mobilization and bone marrow Sca-1+c-Kit+Lin- cell numbers. Our results identify new functions for neurotransmitters and myeloid cytokines in the direct regulation of human and mouse progenitor cell migration and development.

We reported previously that increases in ambient air pollution in the Los Angeles basin increased the risk of low weight and premature birth. However, ambient concentrations measured at monitoring stations may not take into account differential exposure to pollutants found in elevated concentrations near heavy-traffic roadways. Therefore, we used an epidemiologic case-control study design to examine whether residential proximity to heavy-traffic roadways influenced the occurrence of low birth weight (LBW) and/or preterm birth in Los Angeles County between 1994 and 1996. We mapped subject home locations at birth and estimated exposure to traffic-related air pollution using a distance-weighted traffic density (DWTD) measure. This measure takes into account residential proximity to and level of traffic on roadways surrounding homes. We calculated odds ratios (ORs) and risk ratios (RRs) for being LBW and/or preterm per quintile of DWTD. The clearest exposure-response pattern was observed for preterm birth, with an RR of 1.08 [95% confidence interval (CI), 1.01-1.15] for infants in the highest DWTD quintile. Although higher risks were observed for LBW infants, exposure-response relations were less consistent. Examining the influence of season, we found elevated risks primarily for women whose third trimester fell during fall/winter months (OR(term LBW) = 1.39; 95% CI, 1.16-1.67; OR(preterm and LBW) = 1.24; 95% CI = 1.03-1.48; RR(all preterm) = 1.15; 95% CI, 1.05-1.26), and exposure-response relations were stronger for all outcomes. This result is consistent with elevated pollution in proximity to sources during more stagnant air conditions present in winter months. Our previous research and these latest results suggest exposure to traffic-related pollutants may be important.

OBJECTIVE

To estimate the clinical and economic burden of Clostridium difficile-associated disease (CDAD) in Massachusetts over 2 years.

METHODS

A retrospective analysis of Massachusetts hospital discharge data from 1999-2003 was conducted. Cases of CDAD in 2000 were identified using code 008.45 from the International Classification of Diseases, Ninth Revision, Clinical Modification; patients were excluded if they had a hospitalization in the prior year during which a diagnosis of CDAD was recorded. Hospitalizations for CDAD during 2001 and 2002 were examined. For primary case patients (ie, those for which CDAD was the principal diagnosis), all inpatient costs were deemed to be related, whereas for secondary case patients, all-patient refined diagnosis-related group assignment, case severity level, and length of stay (LOS) were used to calculate incremental costs attributable to CDAD. Costs were adjusted to the national level and reported in 2005 US dollars.

RESULTS

The CDAD cohort consisted of 3,692 patients; 59% were women, and the mean age was 70 years. This group represented 1% of all patients hospitalized in Massachusetts in 2000 (96% of hospitals treated at least 1 case; range, 1-257 cases). Of patients who received a first hospital diagnosis of CDAD in 2000, a total of 28% were primary case patients; their mean LOS was 6.4 days, and the mean cost per stay was $10,212. For secondary case patients, the mean CDAD-related incremental LOS was 2.95 days, and the mean incremental cost per stay was $13,675 per patient. Of patients with CDAD who survived their index stay in 2000, a total of 455 (14%) had at least 1 readmission for CDAD within the subsequent 2 years (mean number of readmissions, 1.4 per patient; range, 1-7 readmissions), with a mean time to first readmission of 3 months. Over 2 years, a total of 55,380 inpatient-days and $51.2 million were consumed by CDAD management.

CONCLUSIONS

CDAD is widespread in Massachusetts hospitals. Rehospitalization with CDAD, if it occurs, generally happens within a few months and happens multiple times for some patients. Based on this study's findings, a conservative estimate of the annual US cost for CDAD management is $3.2 billion dollars.

Histone acetylation regulates activation and repression of multiple inflammatory genes known to play critical roles in chronic inflammatory diseases. However, proteins responsible for translating the histone acetylation code into an orchestrated proinflammatory cytokine response remain poorly characterized. Bromodomain and extraterminal (BET) proteins are "readers" of histone acetylation marks, with demonstrated roles in gene transcription, but the ability of BET proteins to coordinate the response of inflammatory cytokine genes through translation of histone marks is unknown. We hypothesize that members of the BET family of dual bromodomain-containing transcriptional regulators directly control inflammatory genes. We examined the genetic model of brd2 lo mice, a BET protein hypomorph, to show that Brd2 is essential for proinflammatory cytokine production in macrophages. Studies that use small interfering RNA knockdown and a small-molecule inhibitor of BET protein binding, JQ1, independently demonstrate BET proteins are critical for macrophage inflammatory responses. Furthermore, we show that Brd2 and Brd4 physically associate with the promoters of inflammatory cytokine genes in macrophages. This association is absent in the presence of BET inhibition by JQ1. Finally, we demonstrate that JQ1 ablates cytokine production in vitro and blunts the "cytokine storm" in endotoxemic mice by reducing levels of IL-6 and TNF-α while rescuing mice from LPS-induced death. We propose that targeting BET proteins with small-molecule inhibitors will benefit hyperinflammatory conditions associated with high levels of cytokine production.

The tumor necrosis factor (TNF) family member APRIL binds to the receptors BCMA on B cells and TACI on B and T cells. To investigate the role of APRIL in immunity, we generated APRIL-deficient mice. APRIL(-/-) mice have normal T and B lymphocyte development, normal T and B cell proliferation in vitro, but increased numbers of CD44(hi)CD62L(lo) CD4(+) effector/memory T cells and increased IgG responses to T-dependent antigens. Serum IgA levels were significantly decreased, and serum IgA antibody responses to mucosal immunization with TD antigens and to type 1 T-independent antigens were impaired in APRIL(-/-) mice. APRIL by itself induced IgA as well as IgG1 isotype switching in CD40-deficient IgM(+)IgD(+) sorted B cells. These results suggest that APRIL down-regulates T cell-dependent antibody responses and promotes IgA class switching.

HSAhi B cells comprise 5 to 10% of adult mouse splenic B cells and are phenotypically and functionally immature. To assess their origin and relationship to mature, heat-stable Ag (HSA)lo B cells, we determined HSA and surface IgD phenotype among splenic B cells throughout development, as well as during reconstitution of lethally irradiated adults given adult B-depleted bone marrow. In each case, HSAhi splenic B cells predominate during the earliest stages of B cell genesis. Furthermore, 5-bromo-2'-deoxyuridine labeling experiments indicate rapid turnover within both the marrow and peripheral HSAhi pools, and adoptive transfer studies show that peripheral HSAhi splenic B cells differentiate to HSAlo within 4 days. Finally, splenic HSAhi B cells reconstitute both primary and memory humoral responses. Together, these data indicate that splenic B cells in the HSAhi subset are an intermediate maturational stage in the adult periphery.

Adherence and invasion are thought to be key events in the pathogenesis of non-typeable Haemophilus influenzae (NTHi). The role of NTHi lipooligosaccharide (LOS) in adherence was examined using an LOS-coated polystyrene bead adherence assay. Beads coated with NTHi 2019 LOS adhered significantly more to 16HBE14 human bronchial epithelial cells than beads coated with truncated LOS isolated from an NTHi 2019 pgmB:ermr mutant (P = 0.037). Adherence was inhibited by preincubation of cell monolayers with NTHi 2019 LOS (P = 0.0009), but not by preincubation with NTHi 2019 pgmB:ermr LOS. Competitive inhibition studies with a panel of compounds containing structures found within NTHi LOS suggested that a phosphorylcholine (ChoP) moiety was involved in adherence. Further experiments revealed that mutations affecting the oligosaccharide region of LOS or the incorporation of ChoP therein caused significant decreases in the adherence to and invasion of bronchial cells by NTHi 2019 (P < 0.01). Analysis of infected monolayers by confocal microscopy showed that ChoP+ NTHi bacilli co-localized with the PAF receptor. Pretreatment of bronchial cells with a PAF receptor antagonist inhibited invasion by NTHi 2109 and two other NTHi strains expressing ChoP+ LOS glycoforms exhibiting high reactivity with an anti-ChoP antibody on colony immunoblots. These data suggest that a particular subset of ChoP+ LOS glycoforms could mediate NTHi invasion of bronchial cells by means of interaction with the PAF receptor.

The leukocyte response in inflammation is characterized by an initial recruitment of polymorphonuclear leukocytes (PMN) preceding a second wave of monocytes to the site of injury or infection. In the mouse, 2 populations of monocytes have been identified, Gr1(-)CCR2(-)CX3CR1(hi) resident monocytes and Gr1(+)CCR2(+)CX3CR1(lo) inflammatory monocytes. Here, intravital microscopy of the musculus cremaster and a subcutaneous air pouch model were used to investigate a possible link between PMN extravasation and the subsequent emigration of inflammatory monocytes in response to local stimulation with PAF. In mice that were made neutropenic by injection of a PMN-depleting antibody, the extravasation of inflammatory monocytes, but not resident monocytes, was markedly reduced compared with mice with intact white blood cell count but was restored by local treatment with secretion of activated PMN. Components of the PMN secretion were found to directly activate inflammatory monocytes and further examination revealed PMN-derived LL-37 and heparin-binding protein (HBP/CAP37/azurocidin) as primary mediators of the recruitment of inflammatory monocytes via activation of formyl-peptide receptors. These data show that LL-37 and HBP specifically stimulate mobilization of inflammatory monocytes. This cellular cross-talk functionally results in enhanced cytokine levels and increased bacterial clearance, thus boosting the early immune response.

Infiltrating inflammatory cells are highly prevalent within the tumor microenvironment and mediate many processes associated with tumor progression; however, the contribution of specific populations remains unclear. For example, the nature and function of tumor-associated neutrophils (TANs) in the cancer microenvironment is largely unknown. The goal of this study was to provide a phenotypic and functional characterization of TANs in surgically resected lung cancer patients. We found that TANs constituted 5%-25% of cells isolated from the digested human lung tumors. Compared with blood neutrophils, TANs displayed an activated phenotype (CD62L(lo)CD54(hi)) with a distinct repertoire of chemokine receptors that included CCR5, CCR7, CXCR3, and CXCR4. TANs produced substantial quantities of the proinflammatory factors MCP-1, IL-8, MIP-1α, and IL-6, as well as the antiinflammatory IL-1R antagonist. Functionally, both TANs and neutrophils isolated from distant nonmalignant lung tissue were able to stimulate T cell proliferation and IFN-γ release. Cross-talk between TANs and activated T cells led to substantial upregulation of CD54, CD86, OX40L, and 4-1BBL costimulatory molecules on the neutrophil surface, which bolstered T cell proliferation in a positive-feedback loop. Together our results demonstrate that in the earliest stages of lung cancer, TANs are not immunosuppressive, but rather stimulate T cell responses.