Ex vivo development of functional human lymph node and bronchus-associated lymphoid tissue

We introduce a novel in vivo model of human mucosal immunity, based on the implantation of human fetal bronchial mucosa and autologous peribronchial lymph node (PLN) in the severe combined immunodeficiency (SCID) mouse. In the SCID host, human fetal bronchi implanted alone retain macrophages and mast cells but lose T cells. In contrast, fetal bronchi co-implanted with PLN contain, in addition to macrophages and mast cells, numerous T cells and B cells, often clustered in intramucosal bronchus-associated lymphoid tissue (BALT). Functionally, bronchus-PLN cografts are able to mount robust alphabeta and gammadelta T-cell-mediated immune responses to Pseudomonas aeruginosa and 3,4-epoxy-3-methyl-1-butyl-diphosphate challenges. No other autologous lymphoid organ (bone marrow, thymus, liver) allows for BALT development in co-implanted bronchi, which suggests special ontogenetic and functional relations between extramucosal PLN and intramucosal BALT. Overall, the bronchus-PLN cograft appears as a promising model for human bronchial immune development and function. Our study is the first to document long-term ex vivo maintenance of functional human lymph nodes as native appendices to mucosal tissue. Our results, therefore, suggest a simple strategy for developing similar experimental models of human immune function in other mucosae.     

AIDS-related cholangiopathy

Several types of biliary tract abnormality of undertermined origin have been described among AIDS patients. The aims of this study are (1) to evaluate whether biliary tree involvement is in fact one or several homogeneous morphological entities, (2) to specify the role of CMV orCryptosporidium sp. infection, and (3) to evaluate the possible efficacy of treatment. Since ultrasound had revealed abnormality in the biliary tree, 26 consecutive AIDS patients underwent cholangiography. Cholangiograms enabled us to distinguish between two types of biliary tract involvement: (1) gradual and regular stenosis of the terminal portion of the common bile duct associated with dilation but without irregularity of the intrahepatic biliary ducts was present in 27% of our cases, and (2) distal stenosis of the extrahepatic biliary ducts combined with diffuse irregularity of the caliber of the intrahepatic bile ducts was present in 73% of our cases. Concomitant infection by CMV orCryptosporidium sp. was significantly more frequent when intrahepatic duct irregularities were present (94%) than when absent (14%,P<0.001). Anti-CMV treatment and sphincterotomy were unsuccessful in treating anomalies of the intrahepatic biliary tract. Conversely, sphincterotomy caused rapid and lasting disappearance of pain in all our patients. In conclusion, biliary tract involvement in AIDS patients is of two types. CMV infection and infection byCryptosporidium sp. are most frequent when the large intrahepatic ducts are implicated.     

Targeting and crossing of the human maternofetal barrier by Listeria monocytogenes: role of internalin interaction with trophoblast E-cadherin

Listeria monocytogenes produces severe fetoplacental infections in humans. How it targets and crosses the maternofetal barrier is unknown. We used immunohistochemistry to examine the location of L. monocytogenes in placental and amniotic tissue samples obtained from women with fetoplacental listeriosis. The results raised the possibility that L. monocytogenes crosses the maternofetal barrier through the villous syncytiotrophoblast, with secondary infection occurring via the amniotic epithelium. Because epidemiological studies indicate that the bacterial surface protein, internalin (InlA), may play a role in human fetoplacental listeriosis, we investigated the cellular patterns of expression of its host receptor, E-cadherin, at the maternofetal interface. E-cadherin was found on the basal and apical plasma membranes of syncytiotrophoblasts and in villous cytotrophoblasts. Established trophoblastic cell lines, primary trophoblast cultures, and placental villous explants were each exposed to isogenic InlA+ or InlA- strains of L. monocytogenes, and to L. innocua expressing or not InlA. Quantitative assays of cellular invasion demonstrated that bacterial entry into syncytiotrophoblasts occurs via the apical membrane in an InlA-E-cadherin dependent manner. In human placental villous explants, bacterial invasion of the syncytiotrophoblast barrier and underlying villous tissue and subsequent replication produces histopathological lesions that mimic those seen in placentas of women with listeriosis. Thus, the InlA-E-cadherin interaction that plays a key role in the crossing of the intestinal barrier in humans is also exploited by L. monocytogenes to target and cross the placental barrier. Such a ligand-receptor interaction allowing a pathogen to specifically cross the placental villous trophoblast barrier has not been reported previously.     

High incidence of recurrent in stent thrombosis after successful treatment of a first in stent thrombosis

Objectives: We attempted to investigate incidence and predictors of recurrent in stent thrombosis (IST) after successful treatment of a first IST. Background: The occurrence of recurrent IST after successful treatment of a first IST may be a decisive factor for patient clinical outcome. However, incidence and predictors of recurrent IST are currently poorly described in the literature. Methods: Between 2003 and 2005, 2,190 patients underwent a percutaneous coronary intervention in our center. During a median follow‐up of 19.4 months, 49 patients (2.24%) presented a first definite IST. Patients presenting with a first IST were followed during an additional median period of 40 months. Their baseline characteristics were listed and cardiovascular events especially recurrent IST as defined by the Academic Research Consortium definition were systematically indexed. Results: Altogether 39 (80%) patients were successfully treated with an effective reperfusion after percutaneous coronary intervention. Fourteen (36%) patients presented a recurrent IST and three presented multiple recurrent IST. The median occurrence time of recurrent IST was 5 days, range between 1 and 11 days. Multivariate analysis identified history of neoplasia (HR = 11.53, 95% CI 2.32–57.37, P = 0.003), residual diameter stenosis (HR = 1.15, 95% CI 1.02–1.29, P = 0.02), and residual dissection after treatment (HR = 8.78, 95% CI 1.85–41.62, P = 0.006), as independent predictors of recurrent IST. Conclusion: Recurrent IST is a frequent and early event after successful treatment of a first IST. Our results suggest that mechanical factors like residual dissection and residual diameter stenosis should be carefully tracked down. In addition, patients with multiple recurrent IST and the early time course of recurrent IST also suggest a potential role of inadequate antiplatelet therapy. © 2008 Wiley‐Liss, Inc.     

Dapsone for thrombocytopenic purpura related to human immunodeficiency virus infection

PURPOSE: The purpose of this study was to determine the effect of dapsone on platelet count in patients with human immunodeficiency virus (HIV)-related autoimmune thrombocytopenia. PATIENTS AND METHODS: Eleven patients with HIV-related thrombocytopenia received dapsone (50 to 125 mg/day) for 2 to 43 months. Patients with the acquired immunodeficiency syndrome were not enrolled. RESULTS: Of the 11 patients, six developed platelet counts above 50 X 10(9)/L and did not require any other specific therapy. No significant side effects were observed. CONCLUSION: We conclude that dapsone may be effective in some patients with HIV-related thrombocytopenia.     

Mild iron deficiency anaemia during pregnancy and lactation in guinea pigs alters amplitudes and auditory nerve velocity,but not brainstem transmission times in the offspring's auditory brainstem response

Objectives

It is well known that postnatal/early childhood iron deficiency (ID) anaemia (IDA) adversely affects infants' cognitive development and neurophysiology. However, the effects of IDA during gestation and lactation on the offspring are largely unknown. To address this health issue, the impact of mild IDA during gestation and lactation on the offsprings' neural maturation was studied in the guinea pig, using auditory brainstem responses (ABRs) latencies and amplitudes.

Methods

Female guinea pigs (n = 10/group) were fed an iron sufficient (ISD) or deficient diet (IDD) (144 and 11.7 mg iron/kg) during the gestation and lactation periods. From postnatal day (PNd) 9 onward, the ISD was given to both groups of weaned offspring. The offsprings' ABRs were collected on PNd24 using a broad range of stimulus intensities in response to 2, 4, 8, 16, and 32 kHz tone pips.

Results

Although the IDA siblings (n = 8) did not differ in brainstem transmission times (BTTs) compared to the IS siblings (n = 8), they showed significant delayed peak I latency at 100 and 80 dB, respectively. Additionally, significantly higher ABR wave amplitudes were observed in the IDA female offspring between 35 and 50 dB (4 kHz), a phenomenon suggestive of a neural hyperactivity (hyperacusis).

Discussion

In support to our previous findings, the present results indicate that a mild IDA during gestation and lactation can have detrimental effects on early development of the offsprings' hearing and nervous systems, particularly on neural synchrony and auditory nerve conduction velocity, but not on BTT.     

Observations of Group Care Worker-Child Interaction in Residential Youth Care: Pedagogical Interventions and Child Behavior

Background

The work of group care workers in residential youth care is often described as professional parenting. Pedagogical interventions of group care workers influence the quality of care for looked-after children.

Objective

The aim of the current study was to observe the pedagogical interventions of group care workers within residential youth care and their associations with child behaviors.

Methods

Group care worker interventions and child behaviors were videotaped during structured observations. Participants included 95 children (64 % boys, M _age = 9.19) and 53 group care workers (74 % female, M _age = 33.79 years). A coding system was developed to code pedagogical interventions and child behaviors.

Results

It showed that group care workers mainly used positive pedagogical interventions (warmth/support and positive control) and seldom used negative pedagogical interventions (permissiveness and negative control). Frustration and anger of children was associated with positive controlling interventions and permissiveness of group care workers. The hypothesis that child anxiety and nervousness is associated with warm and supportive interventions could not be confirmed.

Conclusions

Pedagogical interventions should be part of education, training, and supervision of group care workers.     

Human Papillomavirus Prevalence in Oropharyngeal Cancer before Vaccine Introduction,United States

We conducted a study to determine prevalence of HPV types in oropharyngeal cancers in the United States and establish a prevaccine baseline for monitoring the impact of vaccination. HPV DNA was extracted from tumor tissue samples from patients in whom cancer was diagnosed during 1995–2005. The samples were obtained from cancer registries and Residual Tissue Repository Program sites in the United States. HPV was detected and typed by using PCR reverse line blot assays. Among 557 invasive oropharyngeal squamous cell carcinomas, 72% were positive for HPV and 62% for vaccine types HPV16 or 18. Prevalence of HPV-16/18 was lower in women (53%) than in men (66%), and lower in non-Hispanic Black patients (31%) than in other racial/ethnic groups (68%–80%). Results indicate that vaccines could prevent most oropharyngeal cancers in the United States, but their effect may vary by demographic variables.     

Predictive factors for failure of percutaneous drainage of postoperative abscess after abdominal surgery

Background

The aims of this study were to assess the efficacy of percutaneous drainage of postoperative abscess after abdominal surgery and to identify factors predictive of failed drainage.

Methods

Data from 81 patients with postoperative abdominopelvic abscesses treated with percutaneous drainage were reviewed. Percutaneous drainage failure was considered when surgery was needed to control the sepsis. Predictive variables were sought using univariate and multivariate analyses with logistic regression models.

Results

Successful drainage requiring 1 (n = 46) or 2 (n = 17) procedures was observed in 63 patients (78%; 95% confidence interval, 67%–86%). Surgery was needed in 18 patients (22%; 95% confidence interval, 14%–38%). Residual collection after a first percutaneous drainage was the single predictive factor for failed drainage on univariate and multivariate analyses (P = .0275).

Conclusions

Percutaneous imaging-guided drainage is a feasible and effective method for the treatment of abdominopelvic abscess, with a success rate of 78%. Residual collection is an independent predictor of unfavorable outcome after percutaneous drainage.