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Frequency and character of alternative somatic recombination fates of paralogous genes during T-DNA integration.

A synthetic RBCSB gene cluster was transformed into Arabidopsis in order to simultaneously evaluate the frequency and character of somatic illegitimate recombination, homologous recombination, and targeted gene replacement events associated with T-DNA-mediated transformation. The most frequent type of recombination event observed was illegitimate integration of the T-DNA without activation of the silent DeltaRBCS1B: LUC transgene. Sixteen luc(+) (firefly luciferase positive) T1 plants were isolated. Six of these were due to illegitimate recombination events resulting in a gene trapping effect. Nine resulted from homologous recombination between paralogous RBCSB sequences associated with T-DNA integration. The frequency of somatic homologous recombination associated with T-DNA integration was almost 200 times higher than previously reported rates of meiotic homologous recombination with the same genes. The distribution of (somatic homologous) recombination resolution sites generally fits a fractional interval length model. However, a small region adjacent to an indel showed a significant over-representation of resolution sites, suggesting that DNA mismatch recognition may also play an important role in the positioning of somatic resolution sites. The frequency of somatic resolution within exon-2 was significantly different from that previously observed during meiotic recombination.

Agrobacterium tumefaciens↗

Absence of somatic mosaicism in 17 families with hemophilia B: an analysis with a sensitivity 10- to 1000-fold greater than that of sequencing gels.

Most estimates of germ-line mosaicism have been derived from families in which there has been transmission of a mutated allele to two or more children by an unaffected individual. Previously, analyses for somatic mosaicism detected five such individuals by PCR-based sequencing and haplotype analysis at a sensitivity of approximately 1 mutant per 10 wild-type alleles. To determine whether mutations that occur later in embryogenesis also give rise to somatic mosaicism, we analyzed leukocyte DNA from 17 individuals in whom a mutation in the factor IX gene was known to have originated. Methods capable of detecting 1 mutant allele in 100-10,000 were utilized, and no further examples of somatic mosaicism were detected. If confirmed by future studies, the paucity of somatic mosaicism with mutant:wild-type allele frequencies ranging from 1:10 to 1:1000 (relative to the 11% of somatic mosaicism detected with mutant:wild-type allele frequencies of 1:1 to 1:10) may reflect a higher mutation rate and/or germ-line lineage allocation very early in embryogenesis.

Alleles↗

Somatic NF1 mutational spectrum in benign neurofibromas: mRNA splice defects are common among point mutations.

Neurofibromas, benign tumors that originate from the peripheral nerve sheath, are a hallmark of neurofibromatosis type 1 (NF1). Although loss of heterozygosity (LOH) is a common phenomenon in this neoplasia, it only accounts for part of the somatic NF1 mutations found. Somatic point mutations or the presence of "two hits" in the NF1 gene have only been reported for a few neurofibromas. The large size of the NF1 gene together with the multicellular composition of these tumors has greatly hampered their molecular characterization. Here, we present the somatic NF1 mutational analysis of the whole set of neurofibromas studied by our group and consisting in 126 tumors derived from 32 NF1 patients. We report the identification of 45 independent somatic NF1 mutations, 20 of which are reported for the first time. Different types of point mutations together with LOH affecting the NF1 gene and its surrounding region or extending along the 17q arm have been found. Among point mutations, those affecting the correct splicing of the NF1 gene are common, coinciding with results reported on germline NF1 mutations. In most cases, we have been able to confirm that both copies of the NF1 gene are inactivated. We have also found that both somatic and germline mutations can be expressed at the RNA level in the neoplastic cells. Furthermore, we have observed that the study of more than one tumor derived from the same patient is useful for the identification of the germline mutation. Finally, we have noticed that the culture of neurofibromas and their fibroblast clearance facilitates LOH detection in cases in which it is difficult to determine.

Alleles↗

[The influence of somatic dysfunction on chronic muscular skeletal pain syndromes].

Chronic muscular skeletal pain syndromes (CMSPS) are one of the major health issues. Despite progress in research, treatment and diagnosis remain difficult. The aim of this study was to examine the influence of somatic dysfunction on CMSPS. A total of 216 patients were examined in a standardized way to assess the influence of morphological and psychosocial factors as well as of somatic dysfunction on CMSPS. Measurements were taken at admission. The results showed a statistically significant link between somatic dysfunction, pain chronicity, pain distribution, and pain-related disability. Since there was no or only a minor correlation between somatic dysfunction and the results of the psychometric testing and the morphological findings, somatic dysfunction should be regarded as an independent factor influencing CMSPS and be further scientifically evaluated.

Chronic Disease↗

High accumulation of legumin and Lea-like mRNAs during maturation is associated with increased conversion frequency of somatic embryos from pedunculate oak (Quercus robur L.).

The expression patterns of the storage protein legumin gene and Em- and dehydrin-like homologues were investigated in somatic embryos from Quercus robur L. The effect of different maturation treatments (1% agar, 6% sorbitol, or 5% polyethylene glycol) and partial desiccation on transcript accumulations as well as conversion capacity of somatic embryos was also investigated. Differential expression of putative Em- and two dehydrin-like homologues (designated as Dhn1a and Dhn1b) was detected in somatic oak embryos with heterologous probes. Low expression levels of legumin, Em- and dehydrin-like mRNAs were detected in somatic embryos prior to maturation treatment. A high accumulation of these transcripts was found in embryos that had been cultured on media supplemented with 6% sorbitol or 1% agar. These embryos also showed a high conversion frequency into plantlets. In contrast, no improvement in plant conversion as well as a low accumulation of legumin, Em-like and Dhn1b-like transcripts was observed in embryos that were matured on polyethylene glycol medium. Partial-desiccation treatment significantly enhanced the plant conversion. Nevertheless, a decline in expression of legumin, Em-like and Dhn1a-like homologues was detected upon dehydration. In contrast, Dhn1b and oak homologues to peach dehydrin were also strongly expressed in desiccated embryos. In addition, the treatment of embryos with abscisic acid promoted the accumulation of all investigated transcripts. These results suggest that the regulation of the legumin storage protein gene and Lea-like homologues in somatic oak embryos is under developmental control and that their regulation can be influenced by manipulating the culture conditions.

Abscisic Acid↗

Measurement issues in postpartum depression part 2: assessment of somatic symptoms using the Hamilton Rating Scale for Depression.

Assessment of the somatic symptoms of depression in perinatal women has been debated due to potential overlap with normal physical complaints of pregnancy and childbirth. We investigated the properties of the 17-item Hamilton Rating Scale for Depression (HAMD), which includes somatic items, between 36 weeks gestation and 16 weeks postpartum in 150 women. Scores on the HAMD were highly correlated with scores on measures that avoid somatic items. Scores on somatic items were not well correlated with the total HAMD score in pregnancy, but the correlations increased at 6 weeks postpartum. In contrast, scores on HAMD item 1 ("Depression") were less well correlated with the total score at 6 weeks postpartum than prenatally, suggesting that postpartum women may be less likely to articulate their difficulties as "depression", and more likely to describe somatic complaints such as low energy or insomnia. Implications for the assessment of depression in this population are discussed.

Adult↗

Isolation and characterization of genes associated to cotton somatic embryogenesis by suppression subtractive hybridization and macroarray.

Somatic embryogenesis (SE) is the developmental reprogramming of somatic cells toward the embryogenesis pathway and is a notable illustration of cell totipotency. To identify genes involved in SE, subtractive polymerase chain reaction (PCR) was performed to generate transcripts highly enriched for SE-related genes, using cDNA prepared from a mixture of embryogenic callus and pre-globular somatic embryos, as the tester, and cDNA from non-embryogenic callus, as the driver. After differential screening and subsequent confirmation by reverse Northern blot analysis, a total of 671 differentially expressed cDNA fragments were identified, and 242 uni-genes significantly up-regulated during cotton SE were recovered, as confirmed by Northern blot and reverse-transcription PCR analysis of representative cases, including most previously published SE-related genes in plants. In total, more than half had not been identified previously as SE-related genes, including dominant crucial genes involved in transcription, post-transcription, and transportation, and about one-third had not been reported previously to GenBank or were expected to be unknown, or newly identified genes. We used cDNA arrays to further investigate the expression patterns of these genes in differentiating gradient culture, ranging from pro-embryogenic masses to somatic embryos at every stage. The cDNA collection is composed of a broad repertoire of SE genes which is an important resource for understanding the genetic interactions underlying SE signaling and regulation. Our results suggested that a complicated and concerted mechanism involving multiple cellular pathways is responsible for cotton SE. This report represents a systematic and comprehensive analysis of genes involved in the process of somatic embryogenesis.

Blotting, Northern↗

Gene expression patterns during somatic embryo development and germination in maize Hi II callus cultures.

Gene expression patterns were profiled during somatic embryogenesis in a regeneration-proficient maize hybrid line, Hi II, in an effort to identify genes that might be used as developmental markers or targets to optimize regeneration steps for recovering maize plants from tissue culture. Gene expression profiles were generated from embryogenic calli induced to undergo embryo maturation and germination. Over 1,000 genes in the 12,060 element arrays showed significant time variation during somatic embryo development. A substantial number of genes were downregulated during embryo maturation, largely histone and ribosomal protein genes, which may result from a slowdown in cell proliferation and growth during embryo maturation. The expression of these genes dramatically recovered at germination. Other genes up-regulated during embryo maturation included genes encoding hydrolytic enzymes (nucleases, glucosidases and proteases) and a few storage genes (an alpha-zein and caleosin), which are good candidates for developmental marker genes. Germination is accompanied by the up-regulation of a number of stress response and membrane transporter genes, and, as expected, greening is associated with the up-regulation of many genes encoding photosynthetic and chloroplast components. Thus, some, but not all genes typically associated with zygotic embryogenesis are significantly up or down-regulated during somatic embryogenesis in Hi II maize line regeneration. Although many genes varied in expression throughout somatic embryo development in this study, no statistically significant gene expression changes were detected between total embryogenic callus and callus enriched for transition stage somatic embryos.

DNA, Plant↗

The perception of angina in diabetes: relation to somatic pain threshold and autonomic function.

Silent ischemia is common in diabetic patients with coronary heart disease. These patients may also have more subtle alteration in the perception of angina as reflected by prolongation of anginal perceptual threshold--the time from onset of 0.1 mV ST segment depression to the onset of chest pain during treadmill exercise. Silent ischemia may be associated with a generalized hyposensitivity to pain, although the pathophysiologic mechanism is obscure. The purpose of the present study was to determine whether diabetic patients with prolonged anginal perceptual thresholds are also hyposensitive to painful stimuli and to investigate whether this is associated with autonomic neuropathy. Nineteen diabetic and 25 nondiabetic patients with exertional angina were exercised on a treadmill to measure anginal perceptual threshold. Somatic pain threshold was measured by calf sphygmomanometry. The cuff was inflated rapidly until pain occurred, and six repeat inflations were done to test reproducibility. Because there was no significant difference between measurements (coefficient of variation = 0.156) the mean value for each patient provided a measure of somatic pain threshold. The diabetic group had a longer anginal perceptual threshold (138 +/- 64 seconds vs 34 +/- 51 seconds, p less than 0.001), which correlated positively with the somatic pain threshold (r = 0.5, p = 0.03); patients with more prolonged anginal perceptual thresholds tended to have higher somatic pain thresholds. In the diabetic group anginal perceptual (r = -0.3, p = NS) and somatic pain (r = -0.4, p = 0.05) thresholds tended to increase as the ratio of peak to minimal heart rate during the Valsalva maneuver fell below 1.21, but these variables were unrelated in the nondiabetic group.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗

Cognitive and somatic anxiety.

Three hundred and forty adults (including sports players, recreational exercisers, mediators and sedentary controls) completed three inventories purporting to measure cognitive and somatic aspects of anxiety. These were the Cognitive-Somatic Anxiety Questionnaire (CSAQ) devised by Schwartz, Davidson & Goleman (Psychosomatic Medicine, 40, 321-328, 1978), the Worry-Emotionality Scale (WES, Morris, Davis & Hutchens, Journal of Educational Psychology, 73, 541-555, 1981) and the Lehrer-Woolfolk (1982) Anxiety Symptom Questionnaire (LWASQ). Factor analysis of the CSAQ and WES identified distinct cognitive and somatic anxiety factors in both inventories. Higher somatic than cognitive ratings were recorded on the CSAQ and WES, while the pattern was reversed on the LWASQ. The CSAQ can tentatively be recommended as a useful measure of these two anxiety components. We were unable to confirm an observation made previously in the literature that practice of meditation is associated with reduced cognitive anxiety, or that exercise is linked with lower somatic anxiety.

Adolescent↗

Synchronization of the electrocorticogram by visceral and somatic bradykinin stimulation in anesthetized cats.

The cortical response to visceral and somatic bradykinin stimulation was studied in cats under light to moderate pentobarbital anesthesia. Following the injection of bradykinin into arteries supplying visceral organs and somatic structures, a marked cortical synchronization was recorded. The bilateral, rhythmic discharge in the theta to alpha range was best seen on SI; occasionally the contralateral SI response was more prominent. The cortical synchronization and its distribution were the same for visceral and somatic stimulation. There was only minimal response desensitization to multiple injections of bradykinin in rapid succession. Following transection of the thoracolumbar spinal cord, synchronization failed to develop after hindlimb injections but continued to be seen after forelimb stimulation; similarly, partial denervation of a limb blocked the bradykinin response. No synchronization or desynchronization could be produced by epinephrine and nitroglycerine which caused phasic changes in systemic blood pressure equal to or greater than those seen with bradykinin. The results are discussed in terms of possible pathways and receptors. It is suggested that bradykinin acts primarily on free nerve endings common to visceral and deep somatic tissue with convergence of impulses occurring at spinal and higher levels. The preferential response of SI may reflect afferent activity generated by natural, painful stimulation of deep somatic and visceral organs. Normally, this component would be masked by the concomitant non-specific arousal response of the medial reticulo-thalamic system which was depressed by the anesthetic.

Afferent Pathways↗

Multiple limb autotomy can trigger either ovarian growth or somatic growth in the freshwater crab, Paratelphusa hydrodromous (Herbst).

In female Paratelphusa, there appear to be two alternating dominant physiological tendencies, one biased in favor of reproductive (ovarian) growth and another biased in favor of somatic (regenerative) growth. Multiple limb autotomy (MA), long known to stimulate somatic growth, did so only if the crab was physiologically in the somatic phase. Vitellogenesis was accelerated if the crab was in the reproductive phase at the time of MA. Males and females were found to pass through roughly comparable physiological phases during different seasons of the year. It is not known whether MA has a spermatogenesis-accelerating effect in males, but its effect on somatic growth was dominant while the male was in the somatic phase.

Animals↗

Developing a screening index for community studies of somatization disorder.

Despite the low prevalence of somatization disorder in the community, the section of the Diagnostic Interview Schedule used to make the diagnosis--as well as previous diagnostic interviews for the related diagnoses of hysteria, and Briquet's syndrome--is quite lengthy. This study evaluates a somatization disorder screening index derived from completed interviews from the NIMH sponsored Epidemiologic Catchment Area program. A screening index comprised of 11 symptoms of somatization was derived at the Duke ECA site and replicated across the Johns Hopkins, Yale, and Washington University sites. Across ECA sites a screening threshold of five of 11 symptoms correctly identified 41 of 42 respondents with DIS/DSM-III somatization disorder (97.6%) while correctly classifying 14,600 of 14,750 (99.0%) without the disorder. The screening index offers promise as a screening device for clinical and community studies of somatization disorder.

Humans↗

Somatic emotional disorders in childhood and adolescence.

We conducted a short-term follow-up study of severe somatic emotional disorders in 93 children and adolescents. Our aim was to investigate whether the type of physical presentation influenced the outcome in terms of symptoms and subsequent use of medical services. Three groups of patients were identified. Two groups presented with neurological symptoms and were divided into a pseudo-epilepsy group (n = 23) and other hysterias (n = 30); and a third presented with non-neurological symptoms which we termed 'other somatic presentations' (n = 40). Cases in the hysteria groups were significantly more likely to be female and post-pubertal. Polysymptomatic presentations accounted for 85% of all cases and were as common in boys as in girls at all ages. The greatest number of symptoms was found in the pseudo-epilepsy group. None of the hysterias met DSM III-R criteria for somatization disorder. Outcome in terms of residual physical symptoms and subsequent use of medical services was poorest for the pseudo-epilepsy group, and nearly 40% of these patients were judged by their general practitioner to be unchanged since discharge. By comparison, 85% of all other somatic cases were judged improved since discharge from hospital out-patients. Neither polysymtomatic presentations nor persistent physical symptoms at discharge predicted a poor outcome in any group. The general practitioners considered the psychiatric treatment to have been helpful in the majority of cases, even when the somatic outcome was rated as unchanged.

Adolescent↗

Type A behavior, coping mechanisms and emotions related to somatic risk factors of coronary heart disease in adolescents.

Type A behavior, coping mechanisms, emotions and somatic risk factors of coronary heart disease were studied in 208 randomly selected healthy adolescents. Type A behavior was evaluated by the Wolf-Hunter A-B Rating Scale and a questionnaire developed for the present study. Subjects' coping mechanisms and emotions were assessed by interviews. The somatic risk factors used were SBP, DBP, serum total cholesterol, LDL, HDL, triglycerides and body mass index. In boys, type A behavior consistently correlated negatively with somatic risk factors of CHD while in girls, 'traditional' type A components like impatience and a sense of hurry correlated positively with somatic risk. The key finding was that inability to recognize and express negative emotions and the denial of problems correlated with somatic risk.

Adaptation, Psychological↗

Somatization misattributed to non-pathological vaginal discharge.

Lay explanations and attributional patterns about somatization related to vaginal discharge, a folk illness characterized by undue concern about passing (normal) vaginal discharge and believing that their symptoms are caused by this, were surveyed systematically in 200 consecutive women patients with predominant somatic complaints and 138 normal healthy women. Misattribution was reported 3.5 times more often by women with somatic complaints as compared to the normal women. Sixteen women were absolutely certain that their discharge was totally responsible for their symptoms and illness. Thus, somatization related to vaginal discharge seems to be a frequent undetected problem in women with somatic symptoms.

Adolescent↗

Analysis of germline and in vivo somatic mutations in the human adenine phosphoribosyltransferase gene: mutational hot spots at the intron 4 splice donor site and at codon 87.

We have characterized 18 germline and 10 in vivo somatic mutations in the human adenine phosphoribosyltransferase (APRT) gene. Both germline and in vivo somatic mutations were clustered at the intron 4 splice donor site and at codon 87. In vitro somatic mutations in human APRT do not appear to show this clustering. These findings suggest that the spectrum of germline mutations in APRT may be similar to that incurred by somatic cells in vivo, but different from that seen in cultured cells. Thus, in vivo, rather than in vitro, somatic mutations in this gene may be more representative of mutational events occurring in the germline.

Adenine Phosphoribosyltransferase↗

Neural pathway mediating somatic evoked responses in the caudate nucleus of cats.

The course of somatic afferents to caudate nucleus (CN) was investigated. In curaized cats discrete lesions in intralaminar nuclei, n. centralis medialis (NCM) affect evoked response (ER) in CN to radial nerve stimulation. NCM lesions totally abolish these somatic responses, while after subthalamic lesions ER appear only when a high stimulus intensity is used. Lesions in the specific relay nuclei, ventralis posterior lateralis (VPL) have no effect on somatic ER in CN. Barbiturates (10 mg/kg) abolish somatic ER in CN. Stimulation of the ponto-mesencephalic reticular formation (RF) in a region where visual and somatic responses are recorded shows lowest threshold values for eliciting evoked responses in NCM and CN. The potentials in CN to RF stimulation are restricted to this nucleus and disappear in the internal capsule.

Afferent Pathways↗