Cytomegalovirus hepatitis after bone marrow transplantation: An autopsy study with clinical,histologic and laboratory correlates

Mortality from cytomegalovirus disease after marrow transplantation can be reduced by treatment with antiviral drugs based on the detection of viremia and organ involvement. We examined autopsy liver specimens to determine the frequency, extent and outcome of cytomegalovirus hepatitis and whether cytomegalovirus hepatitis occurred in the absence of cytomegalovirus disease elsewhere. Autopsy specimens from 50 transplant patients were evaluated for cytomegalovirus‐infected cells, in five groups of 10, according to extent of CMV during life and at autopsy. Liver sections were examined by routine light microscopy, immunohistochemistry and in situ DNA hybridization. Clinical and laboratory data collected during the last 30 days of life were analysed as markers of liver cytomegalovirus infection. Cytomegalovirus‐infected cells were detected in the livers of 10/10 patients with cytomegalovirus infection during life and widespread cytomegalovirus at autopsy; in 3/20 livers from patients with cytomegalovirus infection during life but negative liver cultures at autopsy; and in 1/10 livers from cytomegalovirus‐seropositive patients who had been without other evidence of cytomegalovirus infection. Histology detected a lower density of cytomegalovirus‐bearing cells per unit area of liver, compared to immunohistochemistry and in situ hybridization. No cytomegalovirus‐infected cells were detected in livers from cytomegalovirus‐seronegative controls. No distinctive clinical or laboratory findings correlated with liver cytomegalovirus detection. CMV liver disease is common in allografted patients with disseminated CMV but may rarely be isolated to the liver, best demonstrated with IHC and ISH. Massive hepatic necrosis from CMV was not seen in any autopsy liver in this study.     

Insulin resistance is associated with a poor response to intravenous thrombolysis in acute ischemic stroke

OBJECTIVE

Insulin resistance (IR) may not only increase stroke risk, but could also contribute to aggravate stroke prognosis. Mainly through a derangement in endogenous fibrinolysis, IR could affect the response to intravenous thrombolysis, currently the only therapy proved to be efficacious for acute ischemic stroke. We hypothesized that high IR is associated with more persistent arterial occlusions and poorer long-term outcome after stroke thrombolysis.

RESEARCH DESIGN AND METHODS

We performed a prospective, observational, longitudinal study in consecutive acute ischemic stroke patients presenting with middle cerebral artery (MCA) occlusion who received intravenous thrombolysis. Patients with acute hyperglycemia (≥155 mg/dL) receiving insulin were excluded. IR was determined during admission by the homeostatic model assessment index (HOMA-IR). Poor long-term outcome, as defined by a day 90 modified Rankin scale score ≥3, was considered the primary outcome variable. Transcranial Duplex-assessed resistance to MCA recanalization and symptomatic hemorrhagic transformation were considered secondary end points.

RESULTS

A total of 109 thrombolysed MCA ischemic stroke patients were included (43.1% women, mean age 71 years). The HOMA-IR was higher in the group of patients with poor outcome (P = 0.02). The probability of good outcome decreased gradually with increasing HOMA-IR tertiles (80.6%, 1st tertile; 71.4%, 2nd tertile; and 55.3%, upper tertile). A HOMA-IR in the upper tertile was independently associated with poor outcome when compared with the lower tertile (odds ratio [OR] 8.54 [95% CI 1.67–43.55]; P = 0.01) and was associated with more persistent MCA occlusions (OR 8.2 [1.23–54.44]; P = 0.029).

CONCLUSIONS

High IR may be associated with more persistent arterial occlusions and worse long-term outcome after acute ischemic stroke thrombolysis.Stroke is the second most common cause of death and the first leading cause of disability in adults worldwide. Moreover, stroke burden is expected to increase rapidly in the following decades (1). Approximately 85% of all strokes are ischemic, mainly caused by acute thromboembolic occlusion of intracranial arteries. In this context, reperfusion therapies focus on early vessel reopening to save cerebral ischemic tissue at risk, thus reducing final infarct size and neurologic sequelae. Currently, intravenous thrombolysis with tissue plasminogen activator (tPA) remains the only therapy that has proved efficacy for acute ischemic stroke.Insulin resistance (IR), the proposed main pathophysiological mediator of metabolic syndrome (2), may lead to a prothrombotic and proinflammatory state, characterized by a derangement in endogenous fibrinolysis and increased platelet activation (3). These deleterious effects may contribute to explain the well-known association between raised IR and a higher incident or recurrent stroke (4), but whether IR-related metabolic disturbances may also have an impact on the prognosis of acute ischemic stroke once it has occurred and on the response to intravenous thrombolysis remains largely unknown. In this setting, our group previously reported that acute stroke patients fulfilling criteria for metabolic syndrome showed a higher resistance to intravenous thrombolysis (5,6). However, that study was based only on metabolic syndrome clinical criteria and no direct measure to assess IR was performed, thus we could not draw any valid conclusion regarding the relationship between IR and acute stroke outcome. Considering the pathophysiological background and our previous research, we designed a prospective study to test the hypothesis that a high IR is associated with a worse clinical outcome and more persistent arterial occlusions after intravenous thrombolysis for acute ischemic stroke.     

The effect of the administration of human gamma globulins in a model of BCG infection in mice

The effect of the administration of a commercial preparation of human gamma globulins has been evaluated in a mouse model of intranasal infection with BCG. First, we demonstrated the passage of specific antibodies to saliva and lung lavage following the intranasal or intraperitoneal administration to mice of human gamma globulins. This treatment of mice inhibited BCG colonization of the lungs (p < 0.01). A similar inhibitory effect was observed after infection of mice with gamma globulin opsonized BCG organisms (p < 0.01). These results are relevant for the development of new strategies for the control and treatment of tuberculosis.     

Elevated levels of activated CD4 T cells in common variable immunodeficiency: association with clinical findings

BackgroundCommon variable immunodeficiency (CVID) is a very heterogeneous syndrome defined by impaired immunoglobulin production. The primary defect remains unknown, but many reports describe peripheral blood T and B lymphocyte dysfunctions in a substantial proportion of CVID patients. Immunophenotypic alterations on memory B lymphocytes correlate with clinical findings. A B-cell-oriented classification principle of the patients has been proposed.Methods and resultsWe investigated the expression of activation surface molecules on CD4 and CD8 T-cells from 14 patients with CVID, 6 non-CVID hypogammaglobulinemic patients with recurrent infections, 47 asymptomatic HIV-positive patients without AIDS defining conditions and 23 healthy subjects. Lymphocyte subsets were analysed by three-colour flow cytometry. Monoclonal panel: CD38-FITC/HLADR-PE/CD4 or CD8-PerCP. In CVID patients serum levels of CD4 T-cells co-expressing the activation marker HLA-DR [CD4 + DR + (34 %), CD4 + CD38 + DR + (18 %)] were significantly elevated compared with controls. Significant increases in CD8 + DR + (54%), CD8 + CD38 + (43 %) and CD8 + CD38 + DR + (29 %) T-cells were observed in comparison with healthy controls. CVID patients with splenomegaly, lower pre-infusion IgG levels (< 600 mg/dl), autoimmune or lymphoproliferative conditions demonstrated even higher levels of CD4 + CD38 + DR + T cells (22, 22, 21 and 21 % respectively) compared with other CVID patients (13, 13, 15 and 15 % respectively).ConclusionThese findings indicate a state of ongoing T lymphocyte activation which is associated with clinical findings frequently observed in CVID.     

Funktionelle Behandlung bei Humerusschaftfrakturen

Functional bracing of humeral diaphyseal fractures was conceived after initial experiences with a similar method was used in the management of diaphyseal tibial fractures. Over the years, tibial functional bracing underwent major evolutionary changes, and found its indications basically limited to a smaller group of fractures, consisting of closed, axially unstable fractures that experience at the time of the injury an acceptable degree of shortening, and to transverse fracture that are appropriately reduced and rendered stable. On the other hand, functional bracing of diaphyseal humeral fractures has, maintained the initial indications, contraindications and methodology. This article describes the concept, indications and contraindications of functional bracing of humeral diaphyseal fractures and provides results of 620 fractures with complete follow-up. In 97.5% of the patients, the average healing time was 11.5 weeks. 16 patients (2.5%) required operative intervention because of a nonunion and 4 patients (<1 degrees) of the patient had a refracture after brace removal. Nerve function did not return in only one of the 67 patient who had radial nerve palsy.     

Structures and interface mapping of the TIR domain-containing adaptor molecules involved in interferon signaling

Homotypic and heterotypic interactions between Toll/interleukin-1 receptor (TIR) domains in Toll-like receptors (TLRs) and downstream adaptors are essential to evoke innate immune responses. However, such oligomerization properties present intrinsic difficulties in structural studies of TIR domains. Here, using BB-loop mutations that disrupt homotypic interactions, we determined the structures of the monomeric TIR domain-containing adaptor molecule (TICAM)-1 and TICAM-2 TIR domains. Docking of the monomeric structures, together with yeast two hybrid-based mutagenesis assays, reveals that the homotypic interaction between TICAM-2 TIR is indispensable to present a scaffold for recruiting the monomeric moiety of the TICAM-1 TIR dimer. This result proposes a unique idea that oligomerization of upstream TIR domains is crucial for binding of downstream TIR domains. Furthermore, the bivalent nature of each TIR domain dimer can generate a large signaling complex under the activated TLRs, which would recruit downstream signaling molecules efficiently. This model is consistent with previous reports that BB-loop mutants completely abrogate downstream signaling.The extracellular domain of toll-like receptor 4 (TLR4) specifically binds lipopolysaccharides (LPSs) from Gram-negative bacteria, inducing dimerization and leading to the dimerization of cytosolic Toll/interleukin-1 receptor (TIR) domains. This activated conformation of TLR4 recruits the TIR domain of a downstream adaptor molecule, TIR domain-containing adaptor molecule-2 (TICAM-2) [also known as TRIF-related adaptor molecule (TRAM)], that subsequently recruits the TIR domain of another adaptor molecule, TIR domain-containing adaptor molecule-1 (TICAM-1) [also known as TIR domain-containing adaptor inducing IFN-β (TRIF)] (1–3) at endosomes. Eventually this process activates IFN response factors and generates type-I interferons (IFNs) (4–7). Elucidation of the homotypic and heterotypic interactions between TICAM-1 and TICAM-2 is essential for understanding of TLR4-mediated type-I IFN generation (8).A large number of TIR domain structures, including receptors and adaptors, have been determined by X-ray crystallography and NMR. The receptors include TLR1 (9), TLR2 (10), and IL-1R accessory protein-like (IL-1RAPL) (11). Adaptors include myeloid differentiation factor 88 (MyD88) (12) and MyD88 adaptor-like (Mal) (13, 14). In addition, AtTIR (15, 16) derived from Arabidopsis thaliana and PdTIR (17) from bacteria have been solved. Each of these TIR domain structures has a ferredoxin fold with five β-strands (βA–βE), five α-helices (αA–αE), and loops connecting β-strands and α-helices (9). Although homotypic interactions of the TIR domains have been proposed based on the crystal structures, most proposed models have small interacting surfaces, possibly due to crystal contacts. Recently, however, a crystal structure of the TLR10 TIR domain was reported that forms a homotypic dimer mediated by the loop connecting βB and αB (designated “BB-loop”) (18). Interestingly, BB-loop mutations in TLR4 were reported to be dominant-negative and abrogated downstream signaling (19). TICAM-1 and TICAM-2 harboring BB-loop mutations are also dominant-negative and unable to form homotypic interactions (1, 2), reinforcing the importance of BB-loop–mediated homotypic dimer formation in signal propagation.Despite extensive structural studies, it is not known why homotypic interactions are essential for downstream signaling (20–27). To address this issue, it is necessary to discriminate residues required for homotypic and those required for heterotypic interactions. Here, we first determine the structures of the monomeric BB-loop mutants of the TICAM-1 and TICAM-2 TIR domains using NMR. Then, based on the solution structures of the BB-loop mutants, coupled mutagenesis/yeast two-hybrid experiments, and restrained docking calculations, we show that the homotypic interaction of TICAM-2 TIR is essential to form a scaffold for recruiting the TICAM-1 TIR domain.     

Mechanism of enterovirus involvement in epidemic neuropathy: hypothesis regarding pathophysiology

During the epidemic of optic and peripheral neuropathy which occurred in Cuba in 1992-1993, viruses antigenically related to the Coxsackie viruses were isolated from cerebrospinal fluid of patients. Concurrently with the virologic studies, epidemiologic, toxicologic, nutritional, immunologic, and histopathologic investigations were also carried out. Although it was demonstrated that the illness was associated with toxic and nutritional risk factors, it has not been possible to identify a specific etiology for the symptoms observed. Taking into consideration the results obtained in all of the various investigations, we have formulated an integral, multifactorial hypothesis which attempts to explain a pathophysiologic mechanism by which the viruses isolated could participate in the pathogenesis of the illness. We propose that the viral agents produce a persistent infection, and the possibility that they may act as mediator of an autoimmune pathogenic process.     

Functional role of endothelial adhesion molecules in the early stages of brain metastasis

Background

Cellular adhesion molecules (CAMs), which are normally associated with leukocyte trafficking, have also been shown to play an essential role in tumor metastasis to non-CNS sites. However, the role played by CAMs in brain metastasis is largely unexplored. It is known that leukocyte recruitment to the brain is very atypical and that mechanisms of disease in peripheral tissues cannot be extrapolated to the brain. Here, we have established the spatiotemporal expression of 12 key CAMs in the initial phases of tumor seeding in 2 different models of brain metastasis.

Methods

BALB/c or SCID mice were injected intracardially (10⁵ cells/100 μL phosphate-buffered saline with either 4T1-GFP or MDA231BR-GFP cells, respectively (n = 4–6/group), and expression of the CAMs was determined by immunohistochemistry and immunofluorescence colocalisation.

Results

Endothelial expression of E-selectin, VCAM-1, ALCAM, ICAM-1, VLA-4, and β₄ integrin was markedly increased early in tumor seeding. At the same time, the natural ligands to these adhesion molecules were highly expressed on the metastatic tumor cells both in vitro and in vivo. Two of these ligands showed particularly high tumor cell expression (ALCAM and VLA-4), and consequently their functional role in tumor seeding was determined. Antibody neutralization of either ALCAM or VLA-4 significantly reduced tumor seeding within the brain (>60% decrease in tumor number/mm² brain; P < .05–0.01).

Conclusions

These findings suggest that ALCAM/ALCAM and VLA-4/VCAM-1 interactions play an important functional role in the early stages of metastasis seeding in the brain. Moreover, this work identifies a specific subset of ligand-receptor interactions that may yield new therapeutic and diagnostic targets for brain metastasis.     

Re-Accessing Community Mental Health Services for Children and Adolescents

The Journal of Behavioral Health Services & Research - A substantial number of children experience persistent or recurrent problems and may need more than one episode of care. However, there is...