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PubMed1984

Relationships between somatic cell counts and milk production.

The relationship between Dairy Herd Improvement program test-day milk yield and somatic cell counts in milk was analyzed in 34 dairy herds over 3 yr. Estimates of this relationship were more accurate when somatic cell counts were transformed to natural logarithms rather than actual. For 67,707 observations, test-day milk yield decreased with increasing somatic cell count. The decrease of milk yield for second and later lactations, as somatic cell count increased, was greater than for first lactations. When herds were partitioned according to herd milk production (greater than 7700, 6500 to 7700, and less than 6500 kg/yr), decrease of milk yield was linear with increasing somatic cell counts for herds averaging below 7700 kg milk. Regressions were linear, quadratic, and cubic for both parity groups in herds with high production, over 7700 kg/yr. Quarter samples were composited for each cow and cultured. Percentage of infected cows increased as somatic cell counts increased with greater infection rates above 400 X 10(3).

Animals↗
PubMed1988

Preliminary investigation of the properties of somatic cell proteases.

Effect of the plasmin inhibitor 6-amino-n-hexanoic acid on somatic cell proteases (equivalent to 2.3 X 10(6) cells/ml) was determined using a model system of casein micelles dispersed in Jenness/Koops buffer (1.5% wt/vol). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to quantitate casein. There was no effect of 120 mM 6-amino-n-hexanoic acid on casein proteolysis by somatic cell proteases. Molecular weights of casein proteolysis products produced by somatic cell proteases were different from those produced by plasmin. Quantitative and qualitative analyses of pasteurized mastitic milk by SDS-PAGE indicated that a portion of the somatic cell proteolytic activity survived pasteurization. Because 6-amino-n-hexanoic acid does not inhibit somatic cell proteases, it can be used to establish the relative contribution of somatic cell proteases and plasmin to total proteolytic activity in mastitic milk.

Aminocaproates↗
PubMed1994

Adjustment factors and genetic evaluation for somatic cell score and relationships with other traits of Canadian Holsteins.

Test day SCC records were obtained from the Ontario DHI and converted to somatic cell score using a logarithmic transformation. Adjustment factors for stage of lactation and calendar month were obtained for first and later lactations. Effects of stage of lactation were significant and followed a systematic pattern. Seasonal effects were small. Sire estimated breeding values for lactation mean adjusted test day somatic cell scores were obtained from an animal model based on first, later, and all lactations, assuming a heritability of .11 and repeatability of .27. Mean accuracy of estimated breeding values for sires with at least 30 daughters was .64 for first lactation, .76 for second to fifth, and .86 for all lactations. Genetic trends for somatic cell score were not significant. The correlation of breeding values estimated from first lactations with estimates based on later lactations was .62 for sires with at least 50 daughters, which resulted in an approximate genetic correlation of .72. Correlations of sire estimated breeding values for somatic cell score from first lactation with estimated breeding values for milk, fat, protein, fat percentage, protein percentage, and milking speed were .12, .05, .11, -.09, -.02, and .20. Correlations between sire estimated breeding values for somatic cell score and type traits were generally small, but favorable with mammary system, -.13, and fore udder, -.16, and unfavorable with dairy character, .24. Somatic cell score should be considered as an auxiliary trait in dairy cattle breeding programs.

Animal Husbandry↗
PubMed1995

Correlations among somatic cell scores of milk within and across lactations and linear type traits of Jerseys.

Genetic and phenotypic correlations were estimated for means of log2 SCC (somatic cell scores) from the first 305 d, the first 75 d, the first 150 d, 76 to 305 d, and 151 to 305 d of lactation for first and second lactations using REML. Somatic cell scores from the Dairy Records Processing Center in Raleigh, North Carolina for 31,180 Jersey cows sired by 411 bulls were used for analyses. Correlations between sire evaluations for somatic cell scores from this study and linear type traits from the American Jersey Cattle Club were also calculated. The model used for analyses of the somatic cell score means included herd-year of calving, age at first calving, sire, and residual. Heritability estimates for the means ranged from .05 to .15 (.12 for 305-d mean for first lactation). Genetic correlations among the somatic cell score means within first and within second lactation were > or = .79. The genetic correlation between the 305-d mean from first and second lactation was .90. The smallest genetic correlation across lactations was .68. Somatic cell scores measured at various times were under similar genetic control. Phenotypic correlations were usually much smaller than genetic correlations.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1999

Genetic parameters for clinical mastitis, somatic cell score, production, udder type traits, and milking ease in first lactation Holsteins.

Genetic parameters were estimated by restricted maximum likelihood with an animal model on first lactation data of 29,284 French Holstein cows for clinical mastitis, lactation somatic cell score, milking ease, production, and nine udder type traits. The heritability was low for clinical mastitis (0.024), moderate for lactation somatic cell score (0.17) and milking ease (0.17), and ranged from 0.17 to 0.30 for type traits. A high (0.72) but lower than unity genetic correlation was found between clinical mastitis and lactation somatic cell score and indicated that both traits were genetically favorably associated. The antagonism with production was stronger for clinical mastitis than for lactation somatic cell score (genetic correlations 0.45 and 0.15, respectively). Udder depth, fore-udder attachment, and udder balance were favorably associated with lactation somatic cell score and clinical mastitis with genetic correlations ranging from -0.29 to -0.46, whereas low correlations were found with teat length. Milking ease was found to be unfavorably correlated with lactation somatic cell score (genetic correlation 0.44) but not with clinical mastitis.

Animals↗
PubMed2000

T cells can induce somatic mutation in B cell receptor-engaged BL2 Burkitt's lymphoma cells independently of CD40-CD40 ligand interactions.

The B cell surface trigger(s) and the molecular mechanism(s) of somatic hypermutation remain unknown, partly because of the lack of amendable in vitro models. Recently, however, we reported that upon B cell receptor cross-linking and coculture with activated T cells, the Burkitt's lymphoma cell line BL2 introduces mutations in its IgVH gene in vitro. We now confirm the relevance of our culture model by establishing that the entire spectrum of somatic mutations observed in vivo, including insertions and deletions, could be found in the DNA of BL2 cells. Additionally, we show that among four human B cell lines, only two with a centroblast-like phenotype can be induced to mutate. Triggering of somatic mutations in BL2 cells requires intimate T-B cell contacts and is independent of CD40-CD40-ligand (CD40L) interactions as shown by 1) the lack of effect of anti-CD40 and/or anti-CD40L blocking Abs on somatic mutation and 2) the ability of a CD40L-deficient T cell clone (isolated from an X-linked hyper-IgM syndrome patient) to induce somatic mutation in B cell receptor-engaged BL2 cells. Thus, our in vitro model reveals that T-B cell membrane interactions through surface molecules different from CD40-CD40L can trigger somatic hypermutation.

Amino Acid Sequence↗
PubMed1976

X-chromosome inactivation and selection in somatic cells.

X-Chromosome inactivation leads to the formation of mosaic cell populations in the somatic cells of mammalian females. Cells have either a maternal or paternal X-chromosome active. If an individual is heterozygous for a cell autonomous X-linked trait, then a set of built-in cellular markers is provided for the investigation of various developmental phenomena, including selection. In the absence of somatic cell selection the tissues of an X-linked heterozygote should all be mosaic and should have a mosaic composition approaching 1:1. If somatic cell selection is occurring, it should be detectable by a significance shift from the random expected 1:1 mosaicism. The system is effective at detecting selection acting on X-linked loci and on newly arisen somatic autosomal variants, and several examples of somatic cell selection are described. However, it is concluded that somatic cell selection, as described above, is not a normal aspect of ontogeny.

Animals↗
PubMed2000

Variable heavy chain gene analysis of follicular lymphomas: correlation between heavy chain isotype expression and somatic mutation load.

The expansion of follicular lymphomas (FLs) resembles, both morphologically and functionally, normal germinal center B-cell growth. The tumor cells proliferate in networks of follicular dendritic cells and are believed to be capable of somatic hypermutation and isotype switching. To investigate the relation between somatic mutation and heavy chain isotype expression, we analyzed the variable heavy (V(H)) chain genes of 30 FL samples of different isotypes. The V(H) genes of the FLs were heavily mutated (29.3 mutations on average). In addition, isotype-switched lymphomas contained more somatic mutations than immunoglobulin M-positive lymphomas (33.8 mutations per V(H) gene versus 23.0, respectively). In all but one of the FLs, the ratios of replacement versus silent mutations in the framework regions were low, independent of the absolute number of somatic mutations and the level of intraclonal variation. Analysis of relapse samples of 4 FLs showed no obvious increase in somatic mutation load in most FLs and a decrease in intraclonal variation in time. In 3 of 4 cases, we obtained evidence for selection of certain subclones, rather than clonal evolution. Our findings question if intraclonal variation is always a reflection of ongoing somatic hypermutation. This may have implications for the concept of antigen-driven lymphomagenesis. (Blood. 2000;95:2922-2929)

Adult↗
PubMed1999

Somatic embryogenesis and ginsenoside production of Panax ginseng in phytohormone-free medium.

Embryogenic cultures of Panax ginseng were established without using phytohormones. Somatic embryos developed from the roots of an in vitro seedling and from excised leaf and petiole segments cultured in half-macro-salt strength Murashige and Skoog medium. Excised leaf and petiole segments were obtained from in vitro germinated seedlings. Plantlets were subsequently obtained from developing somatic embryos in phytohormone-free media. Shoot formation from somatic embryos was influenced by light intensity. The rate of growth and frequency of embryogenesis were improved when cut-up embryogenic tissues were inoculated into liquid media in the dark. The ginsenoside contents of a 4 year-old field-cultivated root, seedlings from zygotic embryos, somatic embryos and embryogenic tissues were determined and compared. Somatic embryos contained 1.7 times the amount of ginsenoside Rb1 and 2.3 times the amount of ginsenoside Re compared to seedlings from zygotic embryos. Ginsenoside Rd, which was absent in the seedlings derived from zygotic embryos, was detected in somatic embryos. Higher ginsenosides Rd and Rg1 levels were found in embryogenic tissues grown on solid media than in tissues grown in liquid media. The total ginsenoside yields, including the ginsenosides Rb1 and Rg1 levels, of cut-up embryogenic tissues, were higher than those of clump tissues.

Culture Media↗
PubMed2000

[Meiosis-like reduction in the culture system for somatic embryogenesis of Arabidopsis thaliana].

The somatic meiosis-like reduction was observed in some cells in the embryogenic calli of Arabidopsis thaliana. One type was somatic chromosome reductional grouping, in which the chromosomes in a cell either separated into two groups, or separated into more than two groups at prophase or metaphase. The chromosomes separated directly, the morphology of the chromosomes did not show any role of the spindle fibers. Chromosome reductional grouping happened more frequently in polyploid cells. The other type was somatic meiossi which was analogous to that existed in the process of gametogenesis, and characterized by the pairing and synapsis of homologues chromosomes. In the embryogenic calli cultured on dedifferentiation medium, about 3% of the observed cells contained haploid number of chromosomes, while the tetrad cells occurred at a frequency of about 4%. The somatic meiosis-like reduction could result in the recombination of chromosomes in the cells generated by these processes. The roles of somatic meiosis-like reduction in the somatic embryogenesis and somaclonal variations were discussed.

Arabidopsis↗
PubMed2001

Adsorption and survival of faecal coliforms, somatic coliphages and F-specific RNA phages in soil irrigated with wastewater.

This study was carried out to compare the adsorption and survival of faecal coliforms, somatic coliphages and F-specific RNA phages in soil irrigated with wastewater. Adsorption isotherms showed that 3-10x more faecal coliforms than somatic coliphages were adsorbed from wastewater onto soil. The adsorption behavior of F-specific RNA phages was intermediate between those of these two microorganisms. In wastewater, the inactivation factor of somatic coliphages at 8-22 degrees C was 5-7 lower than those of faecal coliforms. F-specific RNA phages have a decrease close to faecal coliforms. In soil, at temperatures of 8-22 degrees C and at moistures of 15-35%, somatic coliphages survived longer than the two other microorganisms. These results seemed to be confirmed by the soil column experiments. The rate of inactivation of all microorganisms was lower in soil than in wastewater and depended extensively on soil temperature and moisture content. Survival was optimal at low temperature (8 degrees C) and low moisture content (15%). Thus, somatic coliphages seemed to be a better indicator of faecal contamination than faecal coliforms under our experimental conditions and based only on the two criteria tested (survival and adsorption). Somatic coliphages were able to contaminate the soil over greater distances and survive better in both wastewater and soil than faecal coliforms. These results need to be confirmed by studies on several soil columns using different kinds of soil and different kinds of wastewater.

Adsorption↗
PubMed2001

How general practice patients with emotional problems presenting with somatic or psychological symptoms explain their improvement.

BACKGROUND: The emotional problems of patients presenting only somatic symptoms are frequently not detected by general practitioners (GPs), yet clinical outcomes have often been found to be no different from emotional problems directly presented. AIM: To compare clinical outcomes and attributions for improvement of patients with emotional problems presenting only somatic symptoms to GPs, with patients directly presenting emotional problems. DESIGN OF STUDY: Survey of patients with General Health Questionnaire (GHQ) scores in the symptomatic range, with follow-up after three months of a repeat GHQ and a questionnaire of patients' attributions for improvement. SETTING: A sample of 152 adult patients from nine general practices in North and East London. METHOD: Consecutive patients were invited to complete an adapted GHQ prior to their consultation. The consultations were audiotaped and coded to indicate the extent to which psychological discussion took place, as against discussion of other issues. The GPs recorded whether they considered each patient to be emotionally disturbed or psychiatrically ill at the time of the consultation, to assess GP detection of emotional disturbance. To form the initial sample, interviews were conducted one to five days after the consultation with patients who intended to present with either psychological or somatic problems, with a follow-up questionnaire after three months. RESULTS: A total of 106 patients provided follow-up information, of whom 57 presented psychological problems directly at initial consultation and 49 presented only somatic symptoms. There were no differences in clinical outcome at three months between the two groups. Somatic presenters who improved were more likely than psychological presenters to attribute improvement to change in their physical health (68% versus 31%) while psychological presenters were more likely to attribute improvement to the GP's listening and counselling in the consultation (44% versus 18%). Other attributions for improvement, such as passage of time, change in life circumstances, support of family and friends, medication, and 'working through problems myself', were equally common in both groups. CONCLUSIONS: Patients with emotional problems presenting only somatic symptoms have equivalent clinical outcomes to patients presenting psychological problems directly, but are more likely to attribute emotional improvements to change in their physical health. For some such emotionally disturbed patients it may be sufficient for GPs to treat the physical health problems and to reassure the patient, without attempting to treat the underlying emotional disturbance.

Adolescent↗
PubMed2001

[Dental complaints are found always between the ears. Somatization in the dental practice].

The aim of the present study was to investigate the occurrence of somatization-specific behaviour in the dental setting and its relationship with patients' report of both dental and psychological complaints. Somatization-specific behaviour was operationalized as an unexplained dental complaint, high dental attendance, a high treatment consumption or an unreasonable demand with regard to treatment. Of the 309 patients 8.7% fulfilled the criteria for somatization-specific behaviour, which was mainly expressed as a high frequency of attendance (6.8%). Women showed significantly more often (73%) somatization-specific behaviour than men (27%). Further, a relation between depression and somatization-specific behaviour was found. Particularly patients with a relatively high level of long-lasting dental complaints demonstrated somatization-specific behaviour.

Adolescent↗
PubMed2002

The relations among body consciousness, somatic symptom report, and information processing speed in chronic fatigue syndrome.

OBJECTIVE: The aim of this study was to assess the potential influence of body consciousness and levels of somatic symptom report upon information processing speed in patients with chronic fatigue syndrome (CFS). BACKGROUND: According to a model of a fixed information processing capacity, it was predicted that in a group of patients with CFS, high body consciousness in combination with a high report of somatic symptoms would affect information-processing speed negatively. METHODS: Information- and motor-processing speed were simultaneously measured with a simple- and a choice-reaction time task, whereas cognitive complaints were rated with two questionnaires. The hypothesized influence of private body consciousness and somatic symptom report upon information-processing speed was tested in a model. A symptom-validity test was used to screen for possible illness behavior. RESULTS: Private body consciousness was directly related to information-processing speed and somatic symptom report. Somatic symptom report was related to both test performance and memory and concentration complaints. CONCLUSIONS: Levels of private body consciousness directly affected somatic symptom report and information-processing speed. This finding supports the role of attentive processes in CFS, and offers, besides possible cerebral dysfunction, an alternative explanation for slowing of information processing in CFS.

Adolescent↗
PubMed1998

[Effects of modulation of abscisic acid during somatic embryogenesis in Lycium barbarum L].

Using Enzyme Linked Immunosorbent Assay (ELISA) method, we determined the ABA contents of different stages in somatic embryogenesis. The results showed that endogenous ABA contents increased to maximum value twice during somatic embryogenesis. After first maximum value of ABA contents embryogenic cells were observed in callus, and simultaneously, there was a specific protein of somatic embryogenesis investigated by SDS-PAGE. This protein accumulates preferentially in embryogenic callus but not in transferred callus. So it is suggested that ABA could promote the expression of specific genes and the synthesis of embryogenic protein during somatic embryogenesis in Lycium barbarum L. and ABA play an important role in globular stage as well. In addition, treatment of non-embryogenic activity callus with 4 mumol/L exogenous ABA could stimulate somatic embryogenesis. And the ABA function mechanism in relation to somatic embryogenesis was discussed.

Abscisic Acid↗
PubMed2002

Sex reversal of genetic females (XX) induced by the transplantation of XY somatic cells in the medaka, Oryzias latipes.

In order to investigate the function of gonadal somatic cells in the sex differentiation of germ cells, we produced chimera fish containing both male (XY) and female (XX) cells by means of cell transplantation between blastula embryos in the medaka, Oryzias latipes. Sexually mature chimera fish were obtained from all combinations of recipient and donor genotypes. Most chimeras developed according to the genetic sex of the recipients, whose cells are thought to be dominant in the gonads of chimeras. However, among XX/XY (recipient/donor) chimeras, we obtained three males that differentiated into the donor's sex. Genotyping of their progeny and of strain-specific DNA fragments in their testes showed that, although two of them produced progeny from only XX spermatogenic cells, their testes all contained XY cells. That is, in the two XX/XY chimeras, germ cells consisted of XX cells but testicular somatic cells contained both XX and XY cells, suggesting that the XY somatic cells induced sex reversal of the XX germ cells and the XX somatic cells. The histological examination of developing gonads of XX/XY chimera fry showed that XY donor cells affect the early sex differentiation of germ cells. These results suggest that XY somatic cells start to differentiate into male cells depending on their sex chromosome composition, and that, in the environment produced by XY somatic cells in the medaka, germ cells differentiate into male cells regardless of their sex chromosome composition.

Animals↗
PubMed1999

[Direct and indirect somatic embryogenesis in Freesia refracta].

Somatic embryogenesis can be induced in tissue cultures of Freesia refracta either directly from the epidermal cells of explant, or indirectly via intervening callus. In direct pathway, somatic embryos were in contact with maternal tissue in a suspensor-like structure. In indirect pathway, the explants first proliferacted to give rise to calluses before embryoids were induced. The two sorts of calluses were defined to embryogenic callus and non-embryogenic callus according to producing of somatic embryos. An indirect somatic embryo is developed from a pre-embryogenically determined cell. This kind of somatic embryo has no suspensor structure instead of a complex with maternal tissue. Somatic embryos have their own vascular tissues, and can develop new plantlets independently.

Culture Techniques↗
PubMed1992

Family psychiatric history of patients with somatization disorder.

We estimated the prevalence of psychiatric disability and disorders (depression, mania, schizophrenia, alcohol disorder, drug disorder, antisocial personality, and somatization) in the parents, siblings, and children of three groups of index cases: primary care patients with somatization disorder (n = 70), primary care patients who approached, but did not reach, DSM-III-R criteria for somatization disorder (n = 29), and randomly-selected community residents with no psychiatric disorder (n = 1633). Nearly all psychiatric disorders were more common in relatives of both patient samples than in relatives of community residents, and the patient samples rarely differed from each other. In the patient samples, the 22.9% rate of patients with multiple unexplained medical problems is substantially higher than previous investigations of somatization would predict. The most common disorders in patients' relatives were depression and alcohol disorder. There was little difference in the rates of depression in relatives of somatization patients who were or were not themselves depressed. A similar pattern occurred for alcohol disorder. There was a high risk for antisocial personality disorder in parents of patients meeting DSM-III-R criteria for somatization disorder, but this increase was not found for other relatives.

Adult↗