Determinants of adherence to non-occupational post HIV exposure prophylaxis

We conducted a study on 140 patients who sought advice at hospital after a non-occupational exposure. The full 28-day course of prophylactic antiretroviral therapy was completed by 109 patients. No HIV contamination was observed. Factors associated with suboptimal adherence were African ethnicity [odds ratio (OR) 13.3, 2.02-87.54] and oral sexual intercourse (OR 8.35, 1.66-41.99). Compliance with prophylactic antiretroviral therapy can be increased by addressing social and psychological barriers to adherence.     

IL-8 and its CXCR1 and CXCR2 receptors participate in the control of megakaryocytic proliferation, differentiation, and ploidy in myeloid metaplasia with myelofibrosis

Myeloproliferation, myelofibrosis, and neoangiogenesis are the 3 major intrinsic pathophysiologic features of myeloid metaplasia with myelofibrosis (MMM). The myeloproliferation is characterized by an increased number of circulating CD34+ progenitors with the prominent amplification of dystrophic megakaryocytic (MK) cells and myeloid metaplasia in the spleen and liver. The various biologic activities of interleukin 8 (IL-8) in hematopoietic progenitor proliferation and mobilization as well as in neoangiogenesis prompted us to analyze its potential role in MMM. We showed that the level of IL-8 chemokine is significantly increased in the serum of patients and that various hematopoietic cells, including platelets, participate in its production. In vitro inhibition of autocrine IL-8 expressed by CD34+ cells with either a neutralizing or an antisense anti-IL-8 treatment increases the proliferation of MMM CD34(+)-derived cells and stimulates their MK differentiation. Moreover, addition of neutralizing anti-IL-8 receptor (CXC chemokine receptor 1 [CXCR1] or 2 [CXCR2]) antibodies to MMM CD34+ cells cultured under MK liquid culture conditions increases the proliferation and differentiation of MMM CD41+ MK cells and restores their polyploidization. Our results suggest that IL-8 and its receptors participate in the altered MK growth that features MMM and open new therapeutic prospects for this still incurable disease.     

Demonstration of a second rapidly conducting cortico-diaphragmatic pathway in humans

Functional imaging studies in normal humans have shown that the supplementary motor area (SMA) and the primary motor cortex (PMC) are coactivated during various breathing tasks. It is not known whether a direct pathway from the SMA to the diaphragm exists, and if so what properties it has. Using transcranial magnetic stimulation (TMS) a site at the vertex, representing the diaphragm primary motor cortex, has been identified. TMS mapping revealed a second area 3 cm anterior to the vertex overlying the SMA, which had a rapidly conducting pathway to the diaphragm (mean latency 16.7 ± 2.4 ms). In comparison to the vertex, the anterior position was characterized by a higher diaphragm motor threshold, a greater proportional increase in motor-evoked potential (MEP) amplitude with voluntary facilitation and a shorter silent period. Stimulus–response curves did not differ significantly between the vertex and anterior positions. Using paired TMS, we also compared intracortical inhibition/facilitation (ICI/ICF) curves. In comparison to the vertex, the MEP elicited from the anterior position was not inhibited at short interstimulus intervals (1–5 ms) and was more facilitated at long interstimulus intervals (9–20 ms). The patterns of response were identical for the costal and crural diaphragms. We conclude that the two coil positions represent discrete areas that are likely to be the PMC and SMA, with the latter wielding a more excitatory effect on the diaphragm.     

CD14 and CD169 expression in human lymph nodes and spleen: specific expansion of CD14+CD169- monocyte-derived cells in diffuse large B-cell lymphomas

The mononuclear phagocyte system of human lymphoid tissue comprises macrophages and dendritic cells (DCs). The heterogeneity of the non-DC mononuclear phagocyte population in human lymphoid tissue has been little addressed. Here, we studied the expression of 2 monocyte-derived markers, CD14 and CD169 (sialoadhesin), in reactive human lymphoid tissue as well as in a series of 51 B-cell lymphomas by immunohistochemistry on paraffin-embedded tissue. We confirmed that lymph node sinusoidal monocyte-derived cells were the only population staining for CD169. Although most sinusoidal histiocytes also expressed CD14, monocyte-derived cells with phagocytosis such as erythrophagocytosis, anthracosis, or tingible bodies macrophage lacked CD14 and CD169. Among B-cell lymphomas, splenic marginal zone lymphoma was the only one associated with an expansion of the CD14(+)CD169(+) cells in the cords. With respect to nodal B-cell lymphomas, CD14(+) cells were rare among B-chronic lymphocytic leukemia, follicular lymphoma (FL), mantle cell lymphoma (MCL). However, strikingly, we found a strong expansion of CD14(+)CD169(-) cells in numerous diffuse large B-cell lymphomas (DLBCLs), except in cases associated with numerous mitoses, apoptotic bodies, and tingible bodies macrophages. When cultivated in granulocyte/macrophage colony stimulating factor/interleukin 4, DLBCL purified CD14(+) cells differentiate into plasmacytoid cells, expressing DC-specific intercellular adhesion molecule 3-grabbing nonintegrin, suggesting dendritic cell differentiation potential. Our observation fits well with the lymph node and host response cluster signatures described in the gene profiling signatures of DLBCL. However, the role of this CD14(+) population that may constitute a microenvironment-related marker of this subgroup of DLBCL remains to be determined.     

Selective sequestration of X4 isolates by human genital epithelial cells: Implication for virus tropism selection process during sexual transmission of HIV

X4 and R5 HIV strains are present in the semen of men infected with HIV but R5 isolates are transmitted preferentially. The role of human epithelial cells in this selection is addressed. Three human cervical cell lines-CaSki, SiHa, and HEC1A-and normal human vaginal cells from HIV-negative donors were characterized for HIV receptor expression and incubated with X4 and R5 laboratory-adapted strains or primary isolates. The infection was assessed by detection of intracellular HIV DNA. The three cell lines were shown to express on their surface the CXCR4 and GalCer molecules, but not the CD4 and CCR5 ones. The three cell lines and normal human vaginal cells were found to be selectively permissive to X4 HIV entry; the preincubation of the cell lines with rhSDF-1 inhibited this infection. The detection of the intracellular proviral DNA in the cell lines and in normal human vaginal cells demonstrated a selective integration of X4 strains. Additional experiments showed that no extracellular RNA was detected in the supernatants of HEC1A cells infected by X4 isolates either after 18 days of culture or after incubation with PHA-stimulated PBMCs and that no transmission occurred after co-culture between infected HEC1A cells and PHA-stimulated PBMCs. These results suggest specific sequestration of X4 strains by genital epithelial cells, which could explain, at least in part, the HIV tropism selection process during sexual intercourse.     

Quality of life,psychological characteristics,and adjustment in parents of children with Attention-Deficit/Hyperactivity Disorder

Purpose

This study investigated quality of life and adjustment mechanisms in parents of children with Attention-Deficit/Hyperactivity Disorder (ADHD).

Method

Ninety parents of children with ADHD completed a sociodemographic questionnaire and self-assessment scales to measure their perceived stress, social support, sense of control, coping strategies and quality of life.

Results

ADHD in children negatively affected parents’ quality of life, especially their psychological well-being and personal fulfillment. Family and couple relationships, as well as daily life activities, were also affected. The severity of the disorder, perceiving the situation as a threat or a loss, feeling guilty and holding on to irrational beliefs were related to emotion-focused coping strategies and to a poorer quality of life. Furthermore, hyperactivity index and stress ratings relative to perceiving the situation as a threat or a loss, and adopting emotion-focused coping strategies, predicted poorer quality of life. In contrast, perceiving the situation as challenging was related to a greater sense of control and personal fulfillment. Moreover, perceiving the situation as challenging and adopting problem-focused coping strategies predicted better quality of life.

Conclusion

The findings highlight the negative effects of ADHD on parent psychological adjustment and underline the need to recommend training programs that improve parenting skills, parents’ perceptions concerning their child’s behavior disorder and parental functioning.

     

Transient intraneuronal Aβ rather than extracellular plaque pathology correlates with neuron loss in the frontal cortex of APP/PS1KI mice

The accumulation of beta-amyloid (Aβ) plaques and neurofibrillary tangles consisting of hyperphosphorylated tau protein are pathological features of Alzheimer’s disease (AD) commonly modeled in mice using known human familial mutations; however, the loss of neurons also found to occur in AD is rarely observed in such models. The mechanism of neuron degeneration remains unclear but is of great interest as it is very likely an important factor for the onset of adverse memory deficits occurring in individuals with AD. The role of Aβ in the neuronal degeneration is a matter of controversial debates. In the present study we investigated the impact of extracellular plaque Aβ versus intraneuronal Aβ on neuronal cell death. The thalamus and the frontal cortex of the APP/PS1KI mouse model were chosen for stereological quantification representing regions with plaques only (thalamus) or plaques as well as intraneuronal Aβ (frontal cortex). A loss of neurons was found in the frontal cortex at the age of 6 months coinciding with the decrease of intraneuronal immunoreactivity, suggesting that the neurons with early intraneuronal Aβ accumulation were lost. Strikingly, no neuron loss was observed in the thalamus despite the development of abundant plaque pathology with levels comparable to the frontal cortex. This study suggests that plaques have no effect on neuron death whereas accumulation of intraneuronal Aβ may be an early transient pathological event leading to neuron loss in AD. O. Wirths and T. A. Bayer have equally contributed to this work.