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1.
Benjamin Volovitz Jacob Amir Hagit Malik Maya Lerman Itzhak Varsano 《The Journal of asthma》1994,31(1):27-34
Administration of theophylline to asthmatic children is frequently associated with an adverse influence on their behavior. The efficacy and behavioral effects of the administration of high-dose theophylline (T) and ketotifen (K) in various combinations were evaluated prospectively in a double-blind, placebo controlled study in 55 children with moderately severe perennial asthma. During a baseline period of 2 weeks, theophylline (serum level of 10-20 μg/ml) was administered to all the children. After this period the patients were randomly allocated into four comparable groups. The children were treated during a 12-week period with: T + K-Placebo (T group); T + K (T + K group); half-dose T + K (T/ 2 + K group); or placebo of both T and K (P group). During the 12-week treatment period, as compared to the baseline period, only the three groups of children who received active therapy (T + P, T + K, T/2 + K) showed a similar reduction in the number of days with asthmatic symptomatology, improvement of the total asthmatic symptoms score, and increased PEFR. The behavioral activity of the children (assessed by the Conner's rating scale) improved significantly only in the groups receiving placebo or T/2 + K. The results of this study suggest that a combination therapy of half the recommended therapeutic dose of theophylline with ketotifen can be clinically as effective as therapy with a full dose of theophylline, but with significantly less adverse behavioral effects. 相似文献
2.
Hagit Cohen Joseph Zohar Michael A Matar Zeev Kaplan Amir B Geva 《Neuropsychopharmacology》2005,58(8):640-650
BACKGROUND: Unsupervised fuzzy clustering (UFC) analysis is a mathematical technique that groups together objects in the multidimensional feature space according to a specified similarity measurement, thereby yielding clusters of similar data points that can be represented by a set of prototypes or centroids. METHODS: Since clinical studies of mental disorders distinguish between affected and unaffected individuals, we designed an inclusion/exclusion criteria (cutoff behavioral criteria [CBC]) approach for animal behavioral studies. The effect of classifying the study population into clearly affected versus clearly unaffected individuals according to behaviors on two behavioral paradigms was statistically significant. RESULTS: Here the raw data from previous studies were subjected to UFC algorithms as a means of objectively testing the validity of the concept of the CBC for our experimental model. The first UFC algorithm yielded two clearly discrete clusters, found to consist almost exclusively of the exposed animals in the one and unexposed animals in the other. The second algorithm yielded three clusters corresponding to animals designated as clearly affected, partially affected, and clearly unaffected. The algorithm for physiological data in addition to behavioral data failed to elicit discrete clusters. CONCLUSIONS: The UFC analysis yielded data that support the conceptual contention of the CBC and lends additional validity to our previous behavioral studies. 相似文献
3.
Dagan O Hochner H Levi H Raas-Rothschild A Sagi M 《American journal of medical genetics》2002,114(2):137-143
Autism is a complex genetic disorder. Chromosome 15 is of particular interest in this disorder, because of previous reports of individuals with autism with chromosomal abnormalities in the 15q11-q13 region. Transmission disequilibrium between polymorphisms in this region and autism has been also been reported in some, but not all studies. Recently, a novel maternally expressed gene, ATP10C, was characterized and mapped to the chromosome 15q11-q13 region, 200 kb distal to UBE3A. It encodes a putative aminophospholipid translocase likely to be involved in the asymmetric distribution of proteins in the cell membrane. Preferential maternal expression has been demonstrated in fibroblasts and brain. Because of its physical location and imprinting pattern, ATP10C was considered to be a candidate gene for chromosome 15-associated autism. In an effort to find the genes responsible for autism in this chromosomal region, 1.5 kb of the 5' flanking region, as well as the coding and splicing regions of ATP10C, were screened for sequence variants. Several polymorphic markers including five nonsynonymous SNPs were identified. To investigate transmission disequilibrium between ATP10C and autism, a family-based association study was conducted for 14 markers in 115 autism trios. No significant transmission disequilibrium was found, suggesting ATP10C is unlikely to contribute strongly to susceptibility to autism in these families. However, due to limited power to detect genes of modest effect, the possible functional role of the nonsynonymous SNPs and the functional implications of the SNPs identified from 5' flanking region and intron 2 splicing region may be evaluated in further studies. 相似文献
4.
5.
Among the 91 house sparrows (Passer domesticus biblicus Hartert, 1904) examined and caught in the Jordan valley, Israel, 79% were found to be infected with Leucocytozoon fringillinarum Woodcock 1910. In the coastal plain of Israel (South of Tel Aviv), Leucocytozoon infection was found in only 3 out of 43 examined sparrows. In the birds examined, Leucocytozoon gametocytes were present, often in large numbers, in the circulating blood of the visceral organs, whereas they were only sporadic or even absent in the peripheral blood. Gametocytes were seen in the brain capillaries in only a few birds. Only one of the heavily infected sparrows was anemic. Leucocytozoon merozoites were present in the liver and kidneys in only a few infected birds. Merogonic infections did not induce any severe pathological changes, while the gametocyte congestion caused dilation of the blood vessels and sinuses. Tissue damage by the gametocyte parasitemia was most evident in the liver and kidneys. Leucocyte infiltration developed alongside the affected vessels; diffuse necrosis developed in the infiltrated areas. In the kidneys, many tubules were degenerated. Leucocytozoon gametocyte infection in sparrows is unique in that it appears to be confined, for most of its duration, to the visceral circulation, resulting in clinical consequences. Geographically, it is confined to habitats presumably supporting vectors. 相似文献
6.
A semiquantitative method (ImmunoComb) for measuring total serum IgE is described and compared with a standard radioimmunoassay (PRIST). ImmunoComb, based on a solid-phase enzyme-linked immunoassay, is self-sufficient and does not require any expensive laboratory equipment. Comparison of these two assays revealed an almost absolute agreement between them (correlation coefficient = 0.95). Furthermore, the ImmunoComb assay also demonstrated its rapidity and temperature independence while maintaining a recovery of 90% to 102%. 相似文献
7.
Calorie restriction (CR) extends the life span of various species through mechanisms that are as yet unclear. Recently, we have reported that mitochondrion-mediated apoptosis was enhanced in alphaMUPA transgenic mice that spontaneously eat less and live longer compared with their wild-type (WT) control mice. To understand the molecular mechanisms underlying the increased apoptosis, we compared alphaMUPA and WT mice for parameters associated with SOD2 (MnSOD), a mitochondrial antioxidant enzyme that converts superoxide radicals into H(2)O(2) and is also known to inhibit apoptosis. The SOD2-related parameters included the levels of SOD2 mRNA, immunoreactivity and enzymatic activity in the liver, lipid oxidation and aconitase activity in isolated liver mitochondria, and the sensitivity of the mice to paraquat, an agent that elicits oxidative stress. In addition, we compared the mice for the levels of SOD2 mRNA after treatment with bacterial lipopolysaccharides (LPS), and for the DNA binding activity of NFkappaB as a marker for the inflammatory state. We extended SOD2 determination to the colon, where we also examined the formation of pre-neoplastic aberrant crypt foci (ACF) following treatment with dimethylhydrazine (DMH), a colonic organotypic carcinogen. Overall, alphaMUPA mice showed reduced basal levels of SOD2 gene expression and activity concomitantly with reduced lipid oxidation, increased aconitase activity and enhanced paraquat sensitivity, while maintaining the capacity to produce high levels of SOD2 in response to the inflammatory stimulus. alphaMUPA mice also showed increased resistance to DMH-induced pre-neoplasia. Collectively, these data are consistent with a model, in which an optimal fine-tuning of SOD2 throughout a long-term regimen of reduced eating could contribute to longevity, at least in the alphaMUPA mice. 相似文献
8.
Hagit Daum Hagar Mor‐Shaked Asaf Ta‐Shma Avraham Shaag Shira Silverstein Mordechai Shohat Orly Elpeleg Vardiella Meiner Tamar Harel 《American journal of medical genetics. Part A》2020,182(4):689-696
Trio exome sequencing is a powerful tool in the molecular investigation of monogenic disorders and provides an incremental diagnostic yield over proband‐only sequencing, mainly due to the rapid identification of de novo disease‐causing variants. However, heterozygous variants inherited from unaffected parents may be inadvertently dismissed, although multiple explanations are available for such scenarios including mosaicism in the parent, incomplete penetrance, imprinting, or skewed X‐inactivation. We report three probands, in which a pathogenic or likely pathogenic variant was identified upon exome sequencing, yet was inherited from an unaffected parent. Segregation of the variants (in NOTCH1, PHF6, and SOX10) in the grandparent generation revealed that the variant was de novo in each case. Additionally, one proband had skewed X‐inactivation. We discuss the possible genetic mechanism in each case, and urge caution in data interpretation of exome sequencing data. We illustrate the utility of expanding segregation studies to the grandparent generation and demonstrate the impact on exome interpretation strategies, by showing that objective genotype data can overcome subjective parental report of lack of symptoms. 相似文献
9.
Hagit Cohen Joseph Zohar Michael A Matar Kaplan Zeev Uri Loewenthal Gal Richter-Levin 《Neuropsychopharmacology》2004,29(11):1962-1970
Post-traumatic stress disorder (PTSD) affects about 20-30% of exposed individuals. Clinical studies of PTSD generally employ stringent criteria for inclusion in study populations, and yet in animal studies the data collection and analysis are generally expressed as a function of exposed vs nonexposed populations, regardless of individual variation in response. Prior data support an approach to animal models analogous to inclusion criteria in clinical studies. This series of studies sought to assess prevalence rates of maladaptive vs adaptive responses determined according to a more stringent approach to the concept of inclusion/exclusion criteria (cutoff behavioral criteria-CBC), consisting of two successive behavioral tests (elevated plus maze and acoustic startle response tests). The rats were exposed to stressors in two different paradigms; exposure to a predator and underwater trauma. The prevalence rates of maladaptive responses to stress in these two distinct models dropped over time from 90% in the acute phase to 25% enduring/maladaptive response at 7 days, to remain constant over 30 days. As setting the affected individuals apart from the unaffected approximates clinical studies, it might also help to clarify some of the pending issues in PTSD research. 相似文献
10.
Nir Paran Yfat Yahalom-Ronen Ohad Shifman Shirley Lazar Ronen Ben-Ami Michal Yakubovsky Itzchak Levy Anat Wieder-Feinsod Sharon Amit Michal Katzir Noga Carmi-Oren Ariela Levcovich Mirit Hershman-Sarafov Alona Paz Rebecca Thomas Hadas Tamir Lilach Cherry-Mimran Noam Erez Sharon Melamed Moria Barlev-Gross Shay Karmi Boaz Politi Hagit Achdout Shay Weiss Haim Levy Ofir Schuster Adi Beth-Din Tomer Israely 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(35)
The current monkeypox virus global spread and lack of data regarding clinical specimens’ infectivity call for examining virus infectivity, and whether this correlates with results from PCR, the available diagnostic tool. We show strong correlation between viral DNA amount in clinical specimens and virus infectivity toward BSC-1 cell line. Moreover, we define a PCR threshold value (Cq ≥ 35, ≤ 4,300 DNA copies/mL), corresponding to negative viral cultures, which may assist risk-assessment and decision-making regarding protective-measures and guidelines for patients with monkeypox. 相似文献