[What a cardiologist needs to know about managing a patient with multiple myeloma]

Multiple myeloma is one of the most frequent hematological malignancies in the elderly and corresponds to the presence of a plasma cell clone. Antitumor treatment combines different therapeutics, including alkylating agents, high-dose corticosteroids, immunomodulators and proteasome inhibitors. These treatments can have cardiovascular side effects that are important to be aware of. The role of the cardiologist is essential in preventing, detecting and managing these effects properly in order to improve the cardiological and oncological prognosis of patients.

[Association of hypertension and antihypertensive agents and the severity of COVID-19 pneumonia. A monocentric French prospective study]

BACKGROUND AND AIM

Angiotensin converting enzyme (ACE) type 2 is the receptor of SARSCoV-2 for cell entry into lung cells. Because ACE-2 may be modulated by ACE inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs), there are concern that patients treated with ACEIs and ARBs are at higher risk for COVID-19 infection or severity. This study sought to analyse the association of severe forms of COVID-19 and mortality with hypertension and a previous treatment with ACEI and ARB.

METHODS

Prospective follow-up of 433 consecutive patients hospitalised for COVID-19 pneumonia confirmed by PCR or highly probable on clinical, biological, and radiological findings, and included in the COVHYP study. Mortality and severe COVID-19 (criteria: death, intensive care unit, or hospitalisation >30 days) were compared in patients receiving or not ACEIs and ARBs. Follow-up was 100% at hospital discharge, and 96.5% at >1month.

RESULTS

Age was 63.6±18.7 years, and 40%) were female. At follow-up (mean 78±50 days), 136 (31%) patients had severity criteria (death, 64 ; intensive care unit, 73; hospital stay >30 days, 49). Hypertension (55.1% vs 36.7%, P<0.001) and antihypertensive treatment were associated with severe COVID-19 and mortality. The association between ACEI/ARB treatment and COVID-19 severity criteria found in univariate analysis (Odds Ratio 1.74, 95%CI [1.14-2.64], P=0.01) was not confirmed when adjusted on age, gender, and hypertension (adjusted OR1.13 [0.59-2.15], P=0.72). Diabetes and hypothyroidism were associated with severe COVID-19, whereas history of asthma was not.

CONCLUSION

This study suggests that previous treatment with ACEI and ARB is not associated with hospital mortality, 1- and 2-month mortality, and severity criteria in patients hospitalised for COVID-19. No protective effect of ACEIs and ARBs on severe pneumonia related to COVID-19 was demonstrated.

Disentangling the role of social cognition processes at early steps of alcohol abuse: The influence of affective theory of mind

Excessive alcohol use among adolescents has become a pressing challenge among Western societies. Accordingly, one of the current research objectives is to identify the processes associated with this harmful habit. Although numerous studies have underlined the role of executive and motivational processes, few have explored emotional and interpersonal abilities at early steps of alcohol abuse. The present study evaluated the role of two social cognition processes, namely theory of mind (ability to infer others' mental states at cognitive and affective levels) and empathy (ability to understand others' feelings at cognitive and affective levels) in adolescents' alcohol consumption. Two hundred and two adolescents (13-20 years old) performed a behavioral task evaluating theory of mind and filled in questionnaires measuring personal data, empathy, alcohol consumption (alcohol abuse and specific binge drinking), as well as depressive and anxiety symptoms. Findings showed that cognitive and affective empathy were negatively associated with alcohol consumption in youth whereas affective theory of mind was related to specific binge drinking. Importantly, affective theory of mind predicted binge drinking in adolescents, even after controlling for age, gender, and education level. These results emphasized the role of social cognition in early alcohol abuse and showed that, beyond inhibition, interpersonal abilities might precipitate excessive drinking in youth.

Long-term survival of children less than six years of age enrolled on the CCG-945 phase III trial for newly-diagnosed high-grade glioma: a report from the Children's Oncology Group

BACKGROUND

We analyzed the long-term survival of children under 6 years of age (<6 years) enrolled upon the Children's Cancer Group (CCG)-945 high-grade glioma (HGG) study to determine the impact of intrinsic biological characteristics as well as treatment upon both survival and quality of life (QOL) in this younger age population.

PROCEDURE

Analyses were undertaken on patients <6 years with institutionally diagnosed HGG enrolled on the CCG-945 trial. Comparisons of survival were performed for patients <3 years of age (<3 years) (treated with intent to avoid irradiation) versus those between 3 and 6 years of age (3-6 years) (treated with irradiation and chemotherapy) at diagnosis. Discordance between the institutional diagnoses of HGG and consensus-reviewed diagnoses led us to perform further survival analyses for both groups. We compared the two groups of patients for biological markers, and evaluated the neuropsychological and QOL outcomes of long-term survivors.

RESULTS

Patients <3 years (n = 49, 19.5% of all enrolled patients) at diagnosis had a 10-year EFS and OS of 29 ± 6.5% and 37.5 ± 7%, respectively, while for patients 3-6 years (n = 34, 13.5% of all enrolled patients) 10-year EFS and OS were 35 ± 8% and 36 ± 8%, respectively. Molecular marker analysis showed that a smaller proportion of patients <3 years harbored TP53 mutations (P = 0.05). Analysis of QOL outcomes with a median length of follow-up of 15.1 years (9.5-19.2) showed comparable results.

CONCLUSIONS

QOL and survival data were similar for the two groups. A larger prospective study is justified to study the efficacy of chemotherapy only regimens in younger children.

Central nervous system (CNS) tumors in the first six months of life: the Children's Hospital Los Angeles experience, 1979-2005

BACKGROUND

The authors report the experience at the Children's Hospital Los Angeles with brain tumors diagnosed before 6 months of age, describing the characteristics of the patients, their tumors, treatment strategies, and prognostic factors.

METHODS

Thirty-three children who were identified between 1979 and 2005 were included. Twelve were female (36%). There were 11 gliomas, 9 choroid plexus tumors, 8 medulloblastomas and supratentorial primitive neuroectodermal tumors (PNET), 2 atypical teratoid/rhabdoid tumors (ATRT), and 1 each of ependymoma, craniopharyngioma, and immature teratoma. Locations of primary tumors included 21 supratentorial (64%) and 7 posterior fossa, and 5 tumors involved both compartments. The treatment strategies included 5 patients with biopsy only, 18 less than gross total resections (<GTRx), and 9 GTRx. Fourteen children (42%) received chemotherapy. Three patients (9%) received irradiation, 1 at initial diagnosis and 2 at relapse. Nine patients (27%) demonstrated metastases, 6 at diagnosis and 3 at relapse.

RESULTS

The Kaplan Meier analysis of event-free survival (EFS) and overall survival (OS) for all patients is 21 +/- 9% and 35 +/- 9% at 5 years. For the glioma patients, the 4-year OS is 48 +/- 17%, while the 5-year OS for the medulloblastoma/PNET/ATRT patients is 12 +/- 11% (p = .39). The 5-year OS for children achieving a GTRx is 64 +/- 21% and for those with <GTRx is 27 +/- 10% (p = .08).

Suppressor of cytokine signaling 3 expression in anaplastic large cell lymphoma

Using a cDNA microarray, we found that suppressor of cytokine signaling 3 (SOCS3) is highly expressed in anaplastic lymphoma kinase (ALK)+ anaplastic large cell lymphoma (ALCL) cell lines. As SOCS3 is induced by activated signal transducer and activator of transcription 3 (STAT3), and ALK activates STAT3, we hypothesized that SOCS3 may play a role in ALK+ ALCL pathogenesis via the Janus kinase 3 (JAK3)-STAT3 pathway. Using ALCL cell lines, we show by coimmunoprecipitation experiments that SOCS3 physically binds with JAK3 in vitro, and that JAK3 inhibition by WHI-P154 downregulates SOCS3 expression. Western blot analysis confirmed expression of SOCS3 and also showed coexpression of phosphorylated (activated) STAT3 (pSTAT3). Direct sequencing of the SOCS3 gene showed no mutations or alternative splicing. In ALCL tumors that were assessed by immunohistochemistry, nine of 12 (75%) ALK+ tumors were SOCS3 positive and eight (67%) coexpressed pSTAT3. In comparison, 18 of 25 (72%) ALK-- tumors were SOCS3 positive and seven (28%) coexpressed pSTAT3. These results show that SOCS3 is overexpressed in ALCL, attributable to JAK3-STAT3 activation and likely related to ALK in ALK+ tumors. However, SOCS3 is also expressed in tumors that lack STAT3 and ALK suggesting alternative mechanisms of upregulation.

Gp120 activates children's brain endothelial cells via CD4

Encephalopathy represents a common and serious manifestation of HIV-1 infection in children, but its pathogenesis is unclear. We demonstrated that gp120 activated human brain microvascular endothelial cells (HBMEC) derived from children in up-regulating ICAM-1 and VCAM-1 expression, IL-6 secretion and increased monocyte transmigration across monolayers. Another novel observation was our demonstration of CD4 in isolated HBMEC and on microvessels of children's brain cryosections. Gp120-induced monocyte migration was inhibited by anti-gp120 and anti-CD4 antibodies. This is the first demonstration that gp120 activates HBMEC via CD4, which may contribute to the development of HIV-1 encephalopathy in children.

Establishment of a human cell line (SKI-DLCL-1) with a t(1;14)(q21;q32) translocation from the ascites of a patient with diffuse large cell lymphoma

Cytogenetic abnormalities at chromosome 1q21 are among the most common second genetic events observed in Non-Hodgkin's Lymphomas and have prognostic significance. Recently, BCL9 has been cloned from a pre-B-cell lymphoblastic leukemia cell line, which carried a t(1:14)(q21;q32). However, among a panel of 39 B-cell malignancies with 1q21 translocation, only two cases showed rearrangement for the BCL9 gene. We report the establishment of a new lymphoma cell line from a patient with relapsed diffuse large cell lymphoma. This cell line SKI-DLCL-1 showed cell surface antigens identical to the original tumor and demonstrated the profile of a mature B-cell phenotype: CD19 and CD20 positive, CD5 and C10 negative. It carried a t(1;14)(q21;q32) translocation identical to the original tumor. Although the clinical presentation was an isolated effusion lymphoma, studies for HIV-1, HHV8 and EBV were all negative. Southern blot analysis demonstrated that BCL9 was not rearranged in the SKI-DLCL-1 cell line. In addition, the BCL9 gene was not over-expressed in SKI-DLCL-1 cell line. The identification of a new locus at 1q21 will help clarify the pathogenesis of B-cell malignancies with a translocation involving this locus.

Cloning and characterization of a Golgin-related gene from the large-scale polymorphism linked to the PML gene

Megabase-scale mapping of the PML gene locus revealed the presence of a large-scale insertion-deletion polymorphism located 25 kb downstream of the PML gene. The polymorphism is organized as a head-to-tail tandem 25-kb repeat containing one to five units. Characterization of the first repeat unit downstream of PML revealed the presence of a gene with strong homology to a family of Golgin-related proteins. The gene, designated GLP (for Golgin linked to PML), is strongly expressed as a 6-kb transcript in normal human testis. In situ hybridization of normal human testis demonstrated that the expression of GLP was restricted to late meiotic germ cells. There was weak expression in late pachytene spermatocytes and strong expression in spermatids. GLP is 50% homologous to other Golgin-related proteins including the vesicle docking protein GM130. Southern blot hybridization of genomic DNA with a GLP probe demonstrated numerous homologous bands outside the PML locus. Three of these loci have been mapped by fluorescence in situ hybridization to chromosome loci 9q34.1, 15q11-q13, and 15q22-q24. Hybridization of a GLP cDNA probe to a zoo blot demonstrated multiple signals in nonhuman primates but not in other species and suggested the duplication of an ancestral locus around 20 million years ago.

Physical linkage of the lysyl oxidase-like (LOXL1) gene to the PML gene on human chromosome 15q22

A contig was constructed centered on the PML (promyelocytic leukemia) gene. Using an exon-trapping approach to identify potential genes from a pool of cosmids located 5' of the PML gene, four exons were identified that showed 100% sequence homology with the previously cloned lysyl oxidase-like (LOXL1) gene. An exon probe identified a single transcript of 2.4 kb on a multitissue Northern blot with a pattern identical to the one reported for the LOXL1 gene. Pulsed-field gel electrophoresis showed comigrating bands for both the PML cDNA and LOXL1 probes, demonstrating a physical linkage between these two genes. These data provide physical mapping information to complement the previous cytogenetic localization of LOXL1.

MUC1 dysregulation as the consequence of a t(1;14)(q21;q32) translocation in an extranodal lymphoma

Cytogenetic abnormalities at chromosome 1q21 are among the most common lesions in diffuse large-cell lymphoma and have been associated with a poor prognosis. A novel cell line, SKI-DLCL-1, was established from ascitic fluid that carries a t(1;14)(q21;q32) chromosomal translocation. Using pulsed-field gel electrophoresis, the breakpoint on the IgH locus mapped to a gamma locus between Calpha(1) and Calpha(2). A cosmid library was prepared from SKI-DLCL-1, and Cgamma-positive clones spanning the breakpoint were identified by screening with fluorescence in situ hybridization. The breakpoint occurs 860 bp downstream of the 3' UTR of the MUC1 gene. The break appears to be a staggered double-strand break consistent with an error in immunoglobulin class switching. The MUC1 gene is highly transcribed and translated, and the protein is highly glycosylated. It is postulated that MUC1 expression is brought under the control of the 3'Ealpha enhancer. MUC1 lies in a region of chromosome 1 characterized by an unusually high density of genes, with 7 known genes in a region of approximately 85 kb. To determine whether there was a pleiotropic effect of the expression of genes in the region as a consequence of the translocation, the expression of 6 additional genes was assessed. None of the other genes in this region (CLK2, propin, COTE1, GBA, metaxin, and thrombospondin 3) are overexpressed in SKI-DLCL-1. Thus, the translocation t(1;14)(q21;q32) seen in both the primary tumor and the derived cell line results in the marked overexpression of MUC1 without affecting the expression of other genes in the region. (Blood. 2000;95:2930-2936)

A novel gene STORP (STOmatin-Related Protein) is localized 2 kb upstream of the promyelocytic gene on chromosome 15q22

We generated a 100-kb map of the region 5' of the PML (promyelocytic leukemia) gene on human chromosome 15q22 and identified a new gene provisionally named STORP for stomatin-related protein. The STORP gene is positioned 2 kb upstream of the PML gene in a head-to-head configuration, and contains 7 exons spanning a genomic region of about 11 kb. There is an open reading frame of 398 amino acids, which would encode a protein of 45 kD. Northern blot analysis demonstrated that the STORP gene has a ubiquitous pattern of expression similar to that of the PML gene. Hybridization of STORP cDNA probe to genomic DNA from other species demonstrated that the STORP gene is conserved among mammalian vertebrates and that the physical linkage with PML is conserved in mice. Unlike PML, the STORP gene is not induced by interferon alpha (IFNalpha), and thus can be distinctly regulated from the PML gene. STORP is homologous to the EPB72 gene coding for the erythrocyte band 7 integral membrane protein or stomatin, which is deficient in a certain form of hereditary stomatocytosis. The function of STORP is unknown. Further study will focus on studying its potential role in red cell function and disorders.

Selective expression of adhesion molecules on human brain microvascular endothelial cells

Human microvascular endothelial cells were isolated from children's brain and examined for their morphological characteristics and upregulation of cell adhesion molecules in response to TNF alpha. Our human brain microvascular endothelial cells (HBMEC) were positive for factor VIII-Rag, carbonic anhydrase IV, Ulex Europeus Agglutinin I, took up fluorescently labeled acetylated low density lipoprotein and expressed gamma glutamyl transpeptidase, demonstrating their brain endothelial cell characteristics. Upon treatment with TNF alpha. VCAM and ICAM but little ELAM was expressed on HBMEC, while VCAM, ICAM and ELAM were clearly evident on HUVEC. This selective expression of cell adhesion molecules was also demonstrated by in situ stimulation of brain tissues. In conclusion, microvascular endothelial cells from childrens brains display selective expression of cell adhesion molecules, which differ from macrovascular endothelial cells. This may have consequences for leukocyte trafficking into the central nervous system.

Ventriculomegaly, delayed myelination, white matter hypoplasia, and "periventricular" leukomalacia: how are they related?

Preterm infants, including some who have sustained intracranial hemorrhage, appear to be at increased risk of lateral ventricular enlargement. Although some occurrences might be due to an impairment of cerebrospinal fluid flow or absorption, many instances of ventriculomegaly without accompanying macrocephaly reflect diffuse white matter damage resulting in diminished (i.e., hypoplastic) white matter or an inadequate density of axons. Perinatally acquired widespread white matter damage is sometimes associated with the focal white matter necrosis. We hypothesize that in some infants both ventriculomegaly and delayed myelination are consequences of disturbances to myelinogenesis that result from an impairment of cells destined to become oligodendroglia or of disturbances to rapidly growing axons. The vulnerability of developing white matter in preterm newborns might, in part, reflect the diminished availability of growth/ survival factors, or a vulnerability to toxins or physiologic perturbations. Awareness that some ventriculomegaly reflects widely distributed white matter damage should prevent overtreatment of what might appear to be hydrocephalus, but is not due to impaired cerebrospinal fluid dynamics. Increased understanding of the phenomena leading to ventriculomegaly related to paucity of white matter should lead to successful efforts to prevent white matter damage in preterm newborns.

The c-ets-1 proto-oncogene is a new early-response gene differentially regulated by cytokines and growth factors in human fibroblasts

In various invasive human tumors, c-ets-1 mRNA was found to be selectively expressed in stromal fibroblasts. We have now investigated the possibility that soluble factors could regulate c-ets-1 expression in cultured human fibroblasts. We show that both conditioned media from tumor cell lines and a number of characterized cytokines and growth factors were able to induce c-ets-1 expression. TNF alpha and IL-1 alpha were the most potent c-ets-1 stimulators, inducing rapid (within 1 h) and long-lasting (19 h) increases of c-ets-1 mRNA and protein expression. In contrast, bFGF, EGF, and PDGF were mainly delayed stimulators, with maximal stimulation being detected by 19 h. In addition, these growth factors potentiated the rapid induction of c-ets-1 by TNF alpha. While all these factors were able to stimulate c-ets-1 expression, TGF beta was found to be ineffective. Using inhibitors of transcription and translation, we also found that increase of c-ets-1 mRNA by TNF alpha resulted from new transcription rather than from stabilization and did not require new protein synthesis. These results demonstrated that c-ets-1 is a new nuclear target for several factors and behaves as an early-response gene for TNF alpha.

A novel L23-related gene 40 kb downstream of the imprinted H19 gene is biallelically expressed in mid-fetal and adult human tissues

The closely linked IGF2 and H19 genes on human chromosome 11p15.5 are monoallelically expressed as a result of genomic imprinting and show altered expression in Wilms' tumors (WTs). To map regional imprinting we have sought to isolate additional human genes close to IGF2/H19 and to characterize their allelic expression patterns. Here we report a novel gene, provisionally named L23MRP [L23 (mitochondrial)-related protein], which is oriented 'tail-to-tail' with H19 and is transcribed to within 40 kb of the last H19 exon. L23MRP is expressed biallelically in many mid-fetal and adult human tissues. This gene is also expressed at normal levels in WTs which have lost expression of H19 either via loss of the maternal chromosome 11p15.5 or via an epigenetic pathway involving site-specific DNA hypermethylation. These data indicate that, at least in post-embryonic stages, L23MRP is functionally insulated from the IGF2/H19 imprinted domain.

Stromal expression of c-Ets1 transcription factor correlates with tumor invasion

The stroma reaction has an important role in tumor growth, invasion, and metastasis. In various invasive human carcinomas, as well as in a mouse model for tumor invasion, transcripts encoding the transcription factor c-Ets1 were detected within stromal fibroblasts, whereas they were absent in epithelial tumor cells. This expression of c-Ets1 was often increased in fibroblasts directly adjacent to neoplastic cells. Endothelial cells of stromal capillaries were also positive for c-Ets1 expression. In contrast, fibroblasts of corresponding noninvasive lesions and of normal tissues were consistently negative. In cultured human fibroblasts stimulated by basic fibroblast growth factor and tumor necrosis factor alpha, the expression of c-Ets1 correlated with the accumulation of transcripts for potential target genes, collagenase-1 and stromelysin-1. The same correlation was observed in some of the invasive carcinomas investigated. These results suggest that c-Ets1 participates in the regulation of tumor invasion in vivo.

Use of texture parameters in the classification of soft tissue tumors

Soft tissue tumors are a challenging group of tumors that presents wide morphologic variety. For pathologists, the degree of cellular differentiation, the cellular and nuclear polymorphism and the mitotic rate are major criteria for diagnosis. In image analysis, the architectural organization of such tumors shows local variations that can be understood as texture variations. This study introduced a method of measuring the architectural organization of soft tissue tumors from texture analysis of tissue sections at low magnification. We studied 40 cases of soft tissue tumors classified by pathologists into three groups according to their histologic patterns. Twelve texture parameters were calculated on subimages of 128 x 128 pixels. Our results show that tissue architecture evaluated by texture analysis provides good discrimination of myxoid, spindle cell and round cell tumors.

Grading of cystosarcoma phyllodes by texture analysis of tissue architecture

Conventional histologic grading of cystosarcoma phyllodes of the breast has not been entirely successful in the prognosis of recurrence or metastasis. Our study first developed a tumor grade classification based on computerized texture features and then compared the classification to conventional grading of these tumors. Evaluation of the tissue architecture of histologic sections was obtained by measuring nine texture features on an image analysis system. Forty cases of cystosarcoma phyllodes were studied. Each parameter was calculated on subimages of 128 x 128 pixels. This size resulted from a preliminary study that confirmed that the difference between texture primitives depends on the area of subimages. We also compared our series to a panel of 20 extramammary sarcomas. The results show that tissue architecture evaluated by texture analysis allows good discrimination between benign, borderline and malignant cystosarcoma phyllodes. Furthermore, extramammary sarcomas and malignant cystosarcoma phyllodes were discriminated well in most cases.

Corpus callosotomy in the lithium-pilocarpine model of seizures and status epilepticus

Section of the corpus callosum (SCC) is a useful surgical therapy in selected types of epilepsy, i.e., tonic, atonic, and intractable generalized convulsive seizures. Experimentally, the effects of SCC have been documented in animal models of focal seizures as well as generalized seizures. The object of this study was to determine the effect of SCC on behavioral and EEG symptomatology in the lithium-pilocarpine model of seizures and status epilepticus in the rat. SCC was well tolerated. Fifty-seven percent of SCC animals never developed status epilepticus, while all control animals developed status epilepticus. None of the SCC animals died after 24 h but 59% of control animals died within 24 h of status. Histology verified the extent of the SCC and demonstrated widespread brain damage in all animals who exhibited status epilepticus after 72 h. SCC was associated with a lesion of hippocampal commissure in 64% of animals in the SCC group. This protective effect was not related to lesion of the skull or the longitudinal sinus. The lesion of the hippocampal commissure may have contributed to the protective effect of SCC, since animals with an isolated lesion of the hippocampal commissure without SCC survived the status and showed an increased latency to seizure and status epilepticus. These data suggest that the lithium-pilocarpine model of status epilepticus may be useful in the study of the mechanism of efficacy of SCC in the treatment of epilepsy.

Evaluation of breast carcinoma chemosensitivity by flow cytometric DNA analysis and computer assisted image analysis

Flow cytometric (FCM) DNA and S-Phase (S%) analyses were compared to computerized image analysis (SAMBA 2005) in 27 breast carcinomas (T3, N0-N1, M0) treated by 3 cycles of preoperative Adriamycin, vincristine, cyclophosphamide, methotrexate, 5-fluorouracil (AVCMF) chemotherapy (CT). Twelve carcinomas had shown objective regression and 15 no regression. Samples studied were obtained by sequential fine-needle cytopunctures. Comparing DNA profiles obtained by both methods before and after the first cycle, it appears that tumors can be divided into 3 groups. In the first group (10 cases), no changes were observed after the first cycle of CT. These tumors before treatment had either single DNA peak without cells in S% and G2M or a major peak with a small S% and G2M peak. The second group (9 cases) showed some changes in DNA profiles with an increased G2M peak but no additional values; these tumors before treatment had a small S% and a G2M peak. In the third group (8 cases), before treatment, all were non-diploid with high S% and high G2M. After the first cycle, all showed obvious changes in DNA profiles with a decrease of the G0/G1 peak and an increased S% and G2M with dispersed additional values along the scale in (G2M) x 2 and (G2M) x 4 regions. When changes were compared to tumor regression in the 1st and 2nd groups, 1/10 and 3/9 cases, respectively, were evaluated as objective regression. In the third group, all had objective regression (p less than 0.001). In most cases, a good correlation was observed with both methods.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunohistochemical analysis of the cellular infiltrate in multiple sclerosis lesions

Immunohistochemical staining of 16 brains post mortem from patients with progressive multiple sclerosis and of two biopsy specimens from patients with acute demyelinating disease was performed using a panel of monoclonal antibodies reactive with T cells and T-cell subsets, B cells, and Ia (HLA-DR) antigens. Lymphocytic perivascular cuffs were most prominent at the edge of active plaques and were occasionally seen in areas with no evidence of demyelination or macrophage infiltration. Perivascular cuffs consisted predominantly of T cells and Ia+ cells, with many T8+ cells and variable numbers of T4+ cells. T8/T4 ratios in cuffs varied between 1:1 and 50:1. In normal-appearing white matter, cuffs were sparse and were predominantly T8+. The distribution of T cells in the parenchyma resembled that seen in perivascular cuffs, namely, predominantly T8+ cells and variable numbers of T4+ cells. Many Ia+ cells were present in active lesions, and the majority of these cells appeared, by histological criteria, to be macrophages. Tissue macrophages were also stained lightly by the anti-T4 antibody. No brain had more T4+ than T8+ cells, determined using both T4 and Leu3a monoclonal antibodies. B1+ cells were rare. These results suggest that the cellular infiltrate in multiple sclerosis consists predominantly of T cells and macrophages and that there is an overrepresentation of T8+ cells compared with T4+ cells.

Focal necrosis of the white matter (periventricular leukomalacia): sonographic, pathologic, and electroencephalographic features

Eleven preterm infants (gestational ages 27-35 weeks) with echogenic paraventricular white matter identified shortly after birth were studied with serial echoencephalograms to fully delineate the sonographic findings characterizing the pathologic stages of white-matter necrosis. Echoencephalograms were compared with autopsy findings and CT scans. Cerebral function was assessed by electroencephalograms and later by neurodevelopmental evaluations. Echogenic areas were observed in the paraventricular white matter in the acute stage. Microscopically, the echogenic white matter consisted of vascular congestion and petechial hemorrhages, but not always with foci of necrosis. Anechoic areas, which characterized the chronic stage, corresponded to cavitary lesions, and these generally appeared within 2 weeks of birth. However, six infants had anechoic lesions by day 4, suggesting that the onset of white-matter damage was antenatal. CT showed mildly decreased attenuation when paraventricular echogenic areas alone or in association with small anechoic areas were observed. Markedly decreased attenuation on CT scans corresponded to large anechoic areas. Resolution of the sonographic and CT findings did not indicate normalization of the white matter since all surviving infants were neurologically abnormal at 1 year. Electroencephalograms with central (rolandic) positive sharp waves were associated with echogenic white matter alone or with evolving anechoic areas. All patients with positive sharp waves on electroencephalograms had large anechoic areas in later studies. Early and serial echoencephalograms are necessary to evaluate white-matter necrosis in preterm infants. When echogenic white matter is identified, electroencephalography can suggest the presence of white-matter necrosis.

Tall vertebrae at birth: a radiographic finding in flaccid infants

It has been well documented that children with severe neuromuscular disorders have tall vertebrae, presumably a consequence of altered mechanical forces. This finding was present in four neonates who were born with severe "floppy" hypotonia due to Werdnig-Hoffmann disease (two cases), nonspecific neonatal myopathy, and congenital muscular dystrophy. Fetal vertebral development is normally modified by intrauterine muscle tension and fetal activity.

Redistribution of Lyt-bearing T cells in acute murine experimental allergic encephalomyelitis: selective migration of Lyt-1 cells to the central nervous system is associated with a transient depletion of Lyt-1 cells in peripheral blood

Experimental allergic encephalomyelitis (EAE) was induced in SJL/J mice by using two injections of spinal cord homogenate in incomplete Freund's adjuvant supplemented with mycobacteria. Analysis of circulating Lyt-bearing subsets by indirect immunofluorescence during the course of acute EAE revealed the following: 1) during the pre-clinical phase of EAE (1 to 2 days before the onset of paralysis), there was a decrease in the percentage of Lyt-1- but not of Lyt-2-bearing cells in peripheral blood, and of both Lyt-1- and Lyt-2-bearing cells in spleen; 2) with the onset of clinically evident EAE, there was a decrease in both Lyt-1 and Lyt-2 cells in peripheral blood and an increase in the percentage of Lyt-1-bearing cells in pooled inguinal and axillary lymph node; and 3) after these early changes, there was a rapid reconstitution of the percentages of total Lyt-bearing cells and of both Lyt-1- and Lyt-2-bearing cells in peripheral blood. Immunohistochemical analysis of the central nervous system infiltrate revealed that the earliest lesions consisted predominantly of Lyt-1 T lymphocytes, with few Lyt-2 cells present. These results demonstrate that the influx of cells of the Lyt-1 inducer subset to the central nervous system in acute EAE is accompanied by a transient decrease in Lyt-1 cells in peripheral blood.

Redistribution of Lyt-bearing T cells in acute murine experimental allergic encephalomyelitis: selective migration of Lyt-1 cells to the central nervous system is associated with a transient depletion of Lyt-1 cells in peripheral blood

Experimental allergic encephalomyelitis (EAE) was induced in SJL/J mice by using two injections of spinal cord homogenate in incomplete Freund's adjuvant supplemented with mycobacteria. Analysis of circulating Lyt-bearing subsets by indirect immunofluorescence during the course of acute EAE revealed the following: 1) during the pre-clinical phase of EAE (1 to 2 days before the onset of paralysis), there was a decrease in the percentage of Lyt-1- but not of Lyt-2-bearing cells in peripheral blood, and of both Lyt-1- and Lyt-2-bearing cells in spleen; 2) with the onset of clinically evident EAE, there was a decrease in both Lyt-1 and Lyt-2 cells in peripheral blood and an increase in the percentage of Lyt-1-bearing cells in pooled inguinal and axillary lymph node; and 3) after these early changes, there was a rapid reconstitution of the percentages of total Lyt-bearing cells and of both Lyt-1- and Lyt-2-bearing cells in peripheral blood. Immunohistochemical analysis of the central nervous system infiltrate revealed that the earliest lesions consisted predominantly of Lyt-1 T lymphocytes, with few Lyt-2 cells present. These results demonstrate that the influx of cells of the Lyt-1 inducer subset to the central nervous system in acute EAE is accompanied by a transient decrease in Lyt-1 cells in peripheral blood.

Prevention of experimental allergic encephalomyelitis (EAE) in the SJL/J mouse by whole body ultraviolet irradiation

The cellular requirements for the in vivo induction of experimental allergic encephalomyelitis (EAE) were investigated in the SJL/J mouse. Exposure of mice to whole body ultraviolet (UV) irradiation, a treatment that has been shown in other systems to interfere selectively with antigen-presenting cell function, prevented the development of clinical and pathologic signs of acute EAE. Splenic T cells from UV-treated animals did not adoptively transfer resistance to EAE, making it unlikely that UV irradiation resulted in the generation of a specific suppressor cell population responsible for protection from EAE. UV irradiation was effective in preventing EAE when administered before initial immunization; UV irradiation was ineffective in modifying ongoing EAE or in preventing relapses of EAE induced by reimmunization. In additional experiments, adult thymectomized, lethally x-irradiated mice reconstituted with syngeneic marrow cells depleted of mature T lymphocytes were found to be resistant to the induction of EAE. Susceptibility was restored by the addition of splenic T cells, demonstrating that EAE induction is T cell-dependent in the mouse. The prevention of an experimental autoimmune demyelinating disease by whole body UV irradiation suggests that interference with the function of Ia-bearing accessory cells may represent an approach for immunotherapy in autoimmune disorders.