Multicentric study of the effect of milk fermented by Lactobacillus casei on the incidence of diarrhoea

The aim of this study was to determine if supplementation of healthy children with milk fermented by yogurt cultures and Lactobacillus casei strain DN-114 001 could affect the incidence of acute diarrhoea when compared with traditional yogurt. The study was a multicentre, randomised, double-blind trial, conducted over four months, on 928 children aged, at inclusion, 6-24 months. The study consisted of two periods: supplementation and observation. Subjects were supplemented daily with 100 g of one of the two dairy products being tested: standard yogurt and milk fermented by yogurt cultures and Lactobacillus casei (10(8) cfu/ml). Frequency or duration of any diarrhoea episode was evaluated. As far as frequency was concerned there was a statistically significant difference between the groups, the incidence of diarrhoea being significantly reduced by supplementation with L. casei fermented milk (15.9%) compared with yogurt (22%) (p = 0.03). These results suggest an additional benefit of L. casei in acute diarrhoea in children compared with standard yogurt.

The effect of supplementation with milk fermented by Lactobacillus casei (strain DN-114 001) on acute diarrhoea in children attending day care centres

The objective of this study was to determine if supplementation with milk fermented by yogurt cultures and Lactobacillus casei (strain DN-114 001) could lessen acute diarrhoea in healthy children. The study was conducted over six months, with 287 children aged 18.9 (SD 6.0) months, comprising three periods of one month supplementation, each month being followed by one month without supplementation. Subjects were supplemented daily with either 125 g or 250 g (according to age) of one of three tested dairy products: standard yogurt, milk fermented by yogurt cultures and Lactobacillus casei (10(8) cfu/ml), or a jellied milk (control product). A daily record was kept of the number and type of stools. Although the incidence of diarrhoea was not shown to be different between the groups, the severity of diarrhoea over the six-month study was significantly decreased (4.3 days) with the supplementation of L. casei fermented milk compared with the jellied milk (8.0 days) (p = 0.009).

Microsatellite deletion mapping on chromosome 10q and mutation analysis of MMAC1, FAS, and MXI1 in human glioblastoma multiforme

Glioblastoma multiforme (GBM) is an end-stage brain tumor of glial origin. Allelic deletions encompassing all or part of chromosome 10q occur frequently in GBMs, indicating that loss of one or more tumor suppressor genes on 10q plays a role in GBM formation. One of these genes is MMAC1 (PTEN), a gene on 10q23 which encodes a dual-specificity protein phosphatase. We carried out a loss of heterozygosity (LOH) analysis of 66 GBM patients using microsatellite markers for 27 loci on 10q. Overall, LOH was detected in 70% of cases, most showing LOH with every informative marker. Eleven patients showed partial 10q deletions, the smallest spanning a 35 cM region distal to D10S187. Sequence analysis of the MMAC1 gene in 45 of these tumors revealed mutations in eleven cases (24%), all with LOH on 10q. None of these mutations was present in normal DNA from the same patients. In addition, we utilized SSCP analysis to test two other candidate genes on 10q: FAS, a cell surface receptor which transduces an apoptotic, cell death signal and MXI1, a transcriptional repressor. The absence of mutations in these genes suggested that FAS and MXI1 are not likely to be tumor suppressor genes physiologically relevant to GBM. These data do support a significant role for MMAC1 in GBM.

Molecular cytogenetic analysis of a t(7;10) in a human glioblastoma cell line

Glioblastoma multiforme (GBM) is the most malignant glial brain tumor in humans. The fact that deleted copies of chromosome 10 are observed frequently in primary GBM tumors supports the hypothesis that one or more tumor suppressor genes located on chromosome 10 occupy crucial growth control checkpoints for glial cells. Deletion mapping in primary GBM tumors using the loss of heterozygosity (LOH) test has implicated the 10q24-10qter region as one possible site for a gene. We report here on the molecular cytogenetic analysis of chromosome 10 abnormalities in a human GBM cell line, JBSA. LOH testing showed that JBSA cells were hemizygous for chromosome 10. Molecular cytogenetic analysis showed that the undeleted homologue was involved in a reciprocal translocation t(7;10)(p21;q22). The translocation breakpoint on chromosome 10 lay within band q22 between D10S19 and D10S4. The fact that JBSA cells lack one homologue of chromosome 10 and carry a translocation breakpoint on the remaining one, proximal to the smallest region of overlap reported in primary tumor deletions, suggests that 10q22 may be another possible site for a tumor suppressor gene involved in GBM.

Chromosome 11p15 deletions in human malignant astrocytomas and primitive neuroectodermal tumors

Chromosome 11p15 deletions occur frequently in several types of human cancer, both sporadic and familial, suggesting that a tumor suppressor gene is present within the deleted chromosome region. We carried out a restriction fragment length polymorphism analysis of chromosome 11p in two types of human brain tumors: malignant astrocytoma, the most common glial tumor in adults; and primitive neuroectodermal tumor (PNET), a malignant embryonic tumor that afflicts children. Loss of heterozygosity was found in 11/43 malignant astrocytomas (26%) and in 3/11 PNETs (27%). Deletion mapping revealed a region of loss on chromosome 11p (p15.4-pter) that was common to both tumor types. To determine whether the c-H-ras gene, located on chromosome 11p in the common region of deletion, was a candidate gene, we analyzed polymerase chain reaction products corresponding to all four c-H-ras coding exons for single-strand conformation polymorphisms. The absence of electrophoretic mobility shifts in tumor DNA compared to leukocyte DNA indicated that c-H-ras gene mutations were most likely not present. These results suggested that loss of a gene on chromosome 11p15 distinct from c-H-ras is an important step in tumorigenesis within the central nervous system in both children and adults.

Establishment and characterization of a human primitive neuroectodermal tumor cell line from the cerebral hemisphere

The primitive neuroectodermal tumors (PNET) comprise a class of malignant nervous system neoplasms that afflict children. These tumors consist of cells that are morphologically identical to the primitive neuroepithelial cells normally seen in early stages of neural embryogenesis, supporting the notion that PNET result from a disturbance in the process of normal neuronal or glial differentiation. In the central nervous system, PNET occur most commonly in the cerebellum (medulloblastomas), but only occasionally in the cerebral hemispheres. We report here the establishment and characterization of a new human cell line (PFSK) derived from a PNET from the cerebral hemisphere of a child. The growth characteristics of PFSK cells were typical of an immortalized, transformed cell line. Cytogenetic and molecular genetic studies showed that three different sublines were present. In one of these sublines, sequences from chromosome 17 had been lost during establishment in culture. Immunocytochemical studies showed that PFSK cells expressed nestin, an intermediate filament protein normally expressed by neuroepithelial stem cells during neurulation. The PFSK cells did not express antigens typically found in terminally differentiated neurons or glia, indicating that this tumor cell line might represent neuroepithelial stem cells prior to commitment to a neuronal or glial lineage.

p53 mutation and loss of heterozygosity on chromosomes 17 and 10 during human astrocytoma progression

The human brain tumor, astrocytoma, typically progresses through three histopathologically defined stages with the passage of time: one premalignant stage, low-grade astrocytoma; and two malignant stages, anaplastic astrocytoma and glioblastoma multiforme. We correlated the results of a sequence analysis of the tumor suppressor gene, p53, and a restriction fragment length polymorphism analysis of chromosomes 17 and 10 in 45 patients with cerebral astrocytomas at different stages. To detect p53 mutations in tumor DNA, we analyzed polymerase chain reaction products corresponding to every p53-coding exon for single-strand conformation polymorphisms and confirmed the mutations by sequencing. Loss of heterozygosity (LOH) was determined by Southern transfer analysis of somatic and tumor DNA from these same patients using polymorphic markers for various loci on chromosomes 10 and 17. p53 mutations were found in 7 of 25 glioblastomas (28%), in 5 of 14 anaplastic astrocytomas (36%) but in 0 of 6 low-grade astrocytomas. p53 mutations were found in 62% of patients with LOH on chromosome 17p. These results indicated that p53 inactivation is a common genetic event in astrocytoma progression that may signal the transition from benign to malignant tumor stages. LOH on chromosome 10 was found in 61% of glioblastomas, in 23% of anaplastic astrocytomas, but in 0% of low-grade astrocytomas. LOH on chromosome 10 and p53 mutation were found together only in patients with glioblastoma multiforme (22%), suggesting that these genetic changes may accumulate during astrocytoma progression.

Allelotype of human malignant astrocytoma

Astrocytoma, the most common brain tumor in humans, is usually malignant and virtually incurable. Two types of malignant astrocytomas can be distinguished histopathologically: anaplastic astrocytoma and glioblastoma multiforme. Studies using DNA markers that detect restriction fragment length polymorphisms have shown that loci on chromosomes 10 and 17p are lost frequently in tumor DNA from malignant astrocytoma patients, suggesting that tumor suppressor genes important in astrocytoma tumorigenesis may be present on 2 different chromosomes. To identify additional regions of chromosome loss, we carried out an allelotype analysis of 41 malignant astrocytoma patients using restriction fragment length polymorphism markers for each arm of every human autosome. Loss of heterozygosity was found for every autosome except chromosome 21, indicating an even greater complexity of genomic alterations than reported previously. Many tumors showed loss of heterozygosity for multiple chromosomes and the number of chromosomes involved correlated with tumor histopathology. A high-resolution restriction fragment length polymorphism study of chromosome 10 loci in these patients showed that loss of broad regions of chromosome 10 was a common event, particularly in glioblastoma multiforme. An allelotype analysis has been carried out on only one other tumor, human colorectal carcinoma. Different profiles of allele loss were observed in malignant astrocytoma and colorectal carcinoma, suggesting that the genetic events leading to these 2 human cancers may proceed along different pathways.

beta-Adrenergic blocking agents. alpha- and gamma-methyl(aryloxy)propanolamines

A series of gamma-methyl- (5) and alpha-methyl(aryloxy)propanolamines (6) were synthesized and evaluated for beta-adrenergic blocking action. The binding constant (KD) was determined for compounds 5a-j on cultured C6-2B astrocytoma cells. Compounds 5a-j and 6a-e were evaluated for beta 1-antagonist action on guinea pig atria and beta 2-antagonist action on guinea pig tracheal strips. Several gamma-methyl(aryloxy)propanolamines showed affinity for beta receptors and a possible preference for beta 2 receptors.

The response of human lymphocyte subpopulations to measles, mumps, and vaccinia viral antigens

A proliferative assay employing virus-infected, fixed monolayers was used to examine the response of PBL and lymphocyte subpopulations to measles, mumps, and vaccinia viruses. The response obtained in this assay was shown to be virus specific. In individuals previously exposed to mumps or vaccinia viruses, a substantial proliferative response was elicited. In contrast, only a small number of individuals responded to measles virus even though they were seropositive for this virus. In the responders, the proliferation to each of the viruses was essentially limited to the T cell fraction and more specifically to the IgG Fc receptor-bearing T cell, the T gamma cell. The response was not dependent on the presence of antiviral antibody in the assay and was therefore apparently not related to the ADCC activity of the T gamma population. The failure of the T non-gamma cell to proliferate was not due to HLA restriction since a response in this cell population could not be elicited on infected autologous skin fibroblasts. The functional significance of the T gamma cell response is not established although a possible immunoregulatory role is considered.

The response of human lymphocyte subpopulations to measles, mumps, and vaccinia viral antigens

A proliferative assay employing virus-infected, fixed monolayers was used to examine the response of PBL and lymphocyte subpopulations to measles, mumps, and vaccinia viruses. The response obtained in this assay was shown to be virus specific. In individuals previously exposed to mumps or vaccinia viruses, a substantial proliferative response was elicited. In contrast, only a small number of individuals responded to measles virus even though they were seropositive for this virus. In the responders, the proliferation to each of the viruses was essentially limited to the T cell fraction and more specifically to the IgG Fc receptor-bearing T cell, the T gamma cell. The response was not dependent on the presence of antiviral antibody in the assay and was therefore apparently not related to the ADCC activity of the T gamma population. The failure of the T non-gamma cell to proliferate was not due to HLA restriction since a response in this cell population could not be elicited on infected autologous skin fibroblasts. The functional significance of the T gamma cell response is not established although a possible immunoregulatory role is considered.