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High-frequency plant regeneration through cyclic secondary somatic embryogenesis in black pepper (Piper nigrum L.).

A high-frequency plantlet regeneration protocol was developed for black pepper (Piper nigrum L.) through cyclic secondary somatic embryogenesis. Secondary embryos formed from the radicular end of the primary somatic embryos which were originally derived from micropylar tissues of germinating seeds on growth regulator-free SH medium in the absence of light. The process of secondary embryogenesis continued in a cyclic manner from the root pole of newly formed embryos resulting in clumps of somatic embryos. Strength of the medium and sucrose concentration influenced the process of secondary embryogenesis and fresh weight of somatic embryo clumps. Full-strength SH medium supplemented with 1.5% sucrose produced significantly higher fresh weight and numbers of secondary somatic embryos while 3.0 and 4.5% sucrose in the medium favored further development of proliferated embryos into plantlets. Ontogeny of secondary embryos was established by histological analysis. Secondary embryogenic potential was influenced by the developmental stage of the explanted somatic embryo and stages up to "torpedo" were more suitable. A single-flask system was standardized for proliferation, maturation, germination and conversion of secondary somatic embryos in suspension cultures. The system of cyclic secondary somatic embryogenesis in black pepper described here represents a permanent source of embryogenic material that can be used for genetic manipulations of this crop species.

Germination↗

Shoot regeneration and somatic embryogenesis from needles of redwood (Sequoia sempervirens (D.Don.) Endl.).

A rapid and effective system of somatic embryogenesis and organogenesis from the in vitro needles of redwood (Sequoia sempervirens (D.Don.) Endl.) had been established. The influences of plant growth regulators (PGRs) and days of seedlings in vitro on adventitious bud regeneration and somatic embryogenesis were studied. The process of somatic embryo formation was also observed. The results showed that embryogenic callus was induced and proliferated on Schenk and Hildebrandt (SH) medium with BA (0.5 mg/l), KT (0.5 mg/l) and IBA (1.0 mg/l). SH medium containing BA (0.5 mg/l), KT (0.2 mg/l) and IBA (0.2 mg/l) effectively promoted adventitious bud regeneration. The highest frequency (66.3%) of direct somatic embryogenesis was obtained in the combination of BA (0.5 mg/l) and IBA (0.5 mg/l). The optimal days of seedling in vitro for adventitious bud and somatic embryogenesis were 30 days and 30-40 days, respectively. The developments of somatic embryos were similar to that of zygotic embryogenesis. The result of histocytological studies indicated that proteins were gradually accumulated in the process of somatic embryo formation and there were two peaks of starch grains accumulation that one was in the embryogenic callus and the other was in the globular embryos. These results indicated that starch and protein were closely related with the energy supply and the molecular base of somatic embryogenesis, respectively.

Embryonic Development↗

Leafy cotyledon genes are essential for induction of somatic embryogenesis of Arabidopsis.

The capacity for somatic embryogenesis was studied in lec1, lec2 and fus3 mutants of Arabidopsis thaliana (L.) Heynh. It was found that contrary to the response of wild-type cultures, which produced somatic embryos via an efficient, direct process (65-94% of responding explants), lec mutants were strongly impaired in their embryogenic response. Cultures of the mutants formed somatic embryos at a low frequency, ranging from 0.0 to 3.9%. Moreover, somatic embryos were formed from callus tissue through an indirect route in the lec mutants. Total repression of embryogenic potential was observed in double (lec1 lec2, lec1 fus3, lec2 fus3) and triple (fus3 lec1 lec2) mutants. Additionally, mutants were found to exhibit efficient shoot regenerability via organogenesis from root explants. These results provide evidence that, besides their key role in controlling many different aspects of Arabidopsis zygotic embryogenesis, LEC/FUS genes are also essential for in vitro somatic embryogenesis induction. Furthermore, temporal and spatial patterns of auxin distribution during somatic embryogenesis induction were analyzed using transgenic Arabidopsis plants expressing GUS driven by the DR5 promoter. Analysis of data indicated auxin accumulation was rapid in all tissues of the explants of both wild type and the lec2-1 mutant, cultured on somatic embryogenesis induction medium containing 2,4-D. This observation suggests that loss of embryogenic potential in the lec2 mutant in vitro is not related to the distribution of exogenously applied auxin and LEC genes likely function downstream in auxin-induced somatic embryogenesis.

Arabidopsis↗

Abscisic acid and stress treatment are essential for the acquisition of embryogenic competence by carrot somatic cells.

Studies of carrot embryogenesis have suggested that abscisic acid (ABA) is involved in somatic embryogenesis. A relationship between endogenous ABA and the induction of somatic embryogenesis was demonstrated using stress-induced system of somatic embryos. The embryonic-specific genes C-ABI3 and embryogenic cell proteins (ECPs) were expressed during stress treatment prior to the formation of somatic embryos. The stress-induction system for embryogenesis was clearly distinguished by two phases: the acquisition of embryogenic competence and the formation of a somatic embryo. Somatic embryo formation was inhibited by the application of fluridone (especially at 10(-4) M), a potent inhibitor of ABA biosynthesis, during stress treatment. The inhibitory effect of fluridone was nullified by the simultaneous application of fluridone and ABA. The level of endogenous ABA increased transiently during stress. However, somatic embryogenesis was not significantly induced by the application of only ABA to the endogenous level, in the absence of stress. These results suggest that the induction of somatic embryogenesis, in particular the acquisition of embryogenic competence, is caused not only by the presence of ABA but also by physiological responses that are directly controlled by stresses.

Abscisic Acid↗

Neural mechanisms of somatic sensory regulation of catecholamine secretion from the adrenal gland.

The reflex regulation of catecholamine secretion of the adrenal gland by various somatic afferent stimuli via sympathetic nerves in the efferent limb of the reflex has been of physiological interest since W.B. Cannon studied the subject. The reflex regulation is characteristically interfered with by emotional involvement which made it difficult to analyze the neural mechanisms in conscious subjects and delayed these studies. However, for the last several years, electrophysiological and endocrinological approaches have advanced with the aid of anesthesia. Recent studies on anesthetized animals have proven that the adrenal sympatho-medullary functions are influenced by various somatic afferent stimuli, either natural or electrical stimulation, and that the somatically induced adrenal sympathetic reflex responses result in changes in catecholamine secretions from the adrenal gland. Somato-adrenal sympathetic reflexes contain both spinal and supraspinal reflex components, the spinal component having a segmental reflex organization, whereas the supraspinal component is generalized and non-segmental. The reflexes are excitatory or inhibitory, depending on the stimuli and species of animals, e.g., excitatory by pinching and inhibitory by brushing in rats. The excitatory responses are mainly mediated by somatic unmyelinated C afferent fiber activation, whereas the inhibitory responses are carried by somatic myelinated A afferent activation. The recent finding that sympatho-adrenal medullary function increases at rest in normal rats during aging, and in SHR-SP even during their youth was reviewed. Although no neural mechanism governing the increase in adrenal sympathetic nerve activity for these cases has been determined, the reflex regulation of such activity by somatic afferent and arterial baroreceptor afferent stimulation is well maintained in aged normal rats. These facts suggest the possibility that the sympatho-adrenal medullary functions can somatically be regulated in the aged. The recent study demonstrating that i.c.v. administered CRF increases in sympatho-adrenal medullary functions was reviewed, because central CRF seems to play an important role in controlling the somatically induced sympatho-adrenal medullary reflex. Finally, all these findings from anesthetized animals seem useful in understanding the neural mechanism of the somato-adrenal sympathetic reflex in conscious subjects.

Adrenal Medulla↗

Depression and hypochondriasis in family practice patients with somatization disorder.

The relationships specified in DSM-III between somatization disorder and depression, and somatization disorder and hypochondriasis require further validation and easier methods of detection for use by primary care physicians. The authors investigated hypochondriacal and depressive symptoms in 13 family practice outpatients with somatization disorder. Pain complaints and depressive symptomatology were present in over 75% of this group, while hypochondriacal symptoms were present in 38%. The mean score on the somatization scale of the Hopkins Symptom Check List (HSCL-90) was greater than that reported for any other group. These findings support the separation of somatization disorder and hypochondriasis and suggest the need for better delineation of depressive subtypes in somatization disorder. The somatization scale of the HSCL-90 should be a useful screen for somatization disorder in future research.

Adult↗

Cryopreservation of somatic embryos of the herbaceous peony (Paeonia lactiflora Pall.) by air drying.

This study was carried out to establish a suitable method for the cryopreservation of somatic embryos of the herbaceous peony. The somatic embryos were obtained from cotyledon and anther cultures on a MS medium supplemented with abscisic acid (ABA) and phenylacetic acid (PAA), respectively. The frequency of somatic embryo formation was the greatest (61%) from the cotyledons cultured on a MS medium supplemented with 1.0 mg l(-1) of ABA. Embryos were also obtained directly from anthers cultured on a MS medium with or without 2.0 mg l(-1) of PAA. For the cryopreservation of peony somatic embryos, the embryos were dried under a stream of sterile air and frozen by immersion in liquid nitrogen. Thawed embryos were germinated into plantlets after placing on a medium containing 0.3 mg l(-1) of gibberellic acid (GA(3)). The frequency of the post-thaw regrowth of cryopreserved somatic embryos was related to their size and desiccation time, the latter ranging from 0 to 2 h. When the somatic embryos were desiccated for 1 h, the frequency of post-thaw regrowth was greater than 66%. The frequency of post-thaw regrowth of the cryopreserved somatic embryos from anthers and cotyledon tissues was generally high when they were 2-3 mm in size. Desiccation may be a suitable method for the cryopreservation of somatic embryos of the herbaceous peony.

Abscisic Acid↗

Somatization and alexithymia in young adult Finnish population.

BACKGROUND: We assessed alexithymia and alexithymic features among young adult subjects with and without somatization symptoms in an epidemiological setting with a sample of young adults. METHODS: The sample consisted of urban 31-year-old subjects (N=1002). Data on somatization were gathered from a review of all public health outpatient records. Subjects with four or more somatization symptoms according to the DSM-III-R criteria were considered somatizers. The 20-item version of the Toronto Alexithymia Scale (TAS-20) was used to measure alexithymia. Subjects with a total TAS score over 60 were considered as being alexithymic, and those with a score under 52 were considered nonalexithymic. Subjects with a total TAS score from 52 to 60 were considered as having alexithymic features. RESULTS: The prevalence of alexithymia was 6.0% among somatizers and 4.8% among subjects without somatization symptoms, and the prevalence of alexithymic features was 7.5% and 12.6%, respectively. CONCLUSIONS: No association was found between alexithymia and somatization in young adult general population. The earlier theory of the association between alexithymia and somatization may be questionable.

Adult↗

Is there a relationship between somatic and autonomic neuropathies in chronic alcoholics?

We investigated the relationship between somatic and autonomic neuropathy in 40 chronic alcoholics. Electromyographic and neurographic studies of upper and lower limbs and a battery of six cardiovascular reflex tests were carried out. A score for somatic or autonomic neuropathy was calculated. All parameters were investigated for possible relationship with total life dose (TLD) of alcohol intake. Somatic neuropathy was detected in 25 patients (62.5%) and autonomic neuropathy in 13 patients (32.5%). Nineteen patients (47.5%) presented only a somatic neuropathy, six patients (15%) had only an autonomic neuropathy, and seven (17.5%) had a combined somatic and autonomic neuropathy. TLD was significantly higher in the group of patients with combined neuropathy than in the group with isolated somatic neuropathy. There was no significant correlation between laboratory parameters of somatic and autonomic neuropathy. Our findings do not support the existence of a parallel involvement of peripheral somatic and autonomic cardiovascular nerve fibers in chronic alcoholism.

Adult↗

Somatic symptoms in patients with chronic non-cancer-related and cancer-related pain.

This study describes and compares patients' reports of somatic symptoms and physicians' ratings of the same symptoms in patients with chronic non-cancer-related and cancer-related pain. Ninety-seven patients with chronic non-cancer-related pain and 100 patients with chronic cancer-related pain reported somatic symptoms using a newly developed checklist of somatic symptoms. Patients also completed the Brief Symptom Inventory-18, Courtland Emotional Control Inventory, Catastrophizing scale, two items from the Coping Strategies Questionnaire (one about efficacy to control and another about ability to decrease pain), and a numeric rating of average pain. After they completed medical histories and physical examinations on patients, physicians rated the degree to which the patients' reported somatic symptoms on the checklist were medically unexplainable. Over 80% of patients in both groups reported somatic symptoms that their physicians rated as not fully explainable. Strong associations existed between patient-reported somatic symptoms and negative mood states. For the majority of patients, results supported a concept of combined illness- and affect-related pathology rather than one of pure somatoform disorder. Assessing patients' reports of somatic symptoms and negative mood states and incorporating physicians' ratings of level of medically unexplainable somatic symptoms were useful for distinguishing these diagnoses.

Adult↗

Is the impact of depressive complaints on the use of general health care services dependent on severity of somatic morbidity?

OBJECTIVE: The aim of this study was to examine the effects of depressive complaints and chronic medical illnesses on prospective somatic health care utilization and the possible heterogeneity of the effect of depressive complaints across levels of medical illness severity. METHODS: Data from a community-based sample of adults (n=9428) were used, of whom a health survey and claims data, indicating health care use, were available. Assessments of depressive complaints and somatic illnesses were based on self-report. Binomial regression analyses were used to study the expected relations. RESULTS: Depressive complaints and somatic morbidity were both positively related to general health care utilization. Somatic morbidity has an attenuating effect on the impact of depressive complaints: If it becomes more severe, the impact of depressive complaints on utilization is reduced. Depressive complaints are especially related to the use of paramedic services, use of prescription drugs, and consultations of medical specialists. CONCLUSION: Depressive complaints predict somatic health care utilization, but somatic morbidity attenuates this relation. Future research on this subject should include interaction effects of depressive complaints and somatic morbidity. Interventions aiming to reduce excess use related to mental distress should be primarily targeted on subjects with mental distress who have no comorbid somatic morbidity.

Adolescent↗

Cognitive distortions of somatic experiences: revision and validation of a measure.

The article reports on the revision of the Cognitive Errors Questionnaire (CEQ). The CEQ which was originally developed to measure cognitive distortions specific to chronic pain, has been significantly shortened and made applicable to a wider range of somatic problems. The Cognitive Errors Questionnaire-Revised (CEQ-R) contains two subscales: Somatic--distortions specific to somatic experiences; and General--distortions to everyday life events. Validation of the scale with CFS, depressed, and chronic pain groups and healthy controls confirms the CEQ-R loads onto general and somatic factors. Both subscales have high internal consistency and good test-retest reliability. The pattern of subjects' responses to the CEQ-R scores showed that the depressed group scored significantly higher on the General CEQ-R scale than the other groups, whereas the CFS and chronic pain groups scored higher than healthy controls on the Somatic CEQ-R. Somatic CEQ-R scores showed a significant decrease over the course of a pain management program, with a concomitant decrease in disability and depression scores. Further analyses showed the Somatic CEQ-R to be significantly related to self and symptom focusing, whereas the General CEQ-R was found to be significantly correlated with higher depression, lower self-esteem, and self focusing. The CEQ-R may be a useful instrument to examine the relationship between cognitive distortions and disability in a variety of illnesses, and to differentiate primary depression from overlapping somatic disorders.

Adaptation, Psychological↗

Persistent somatization in cancer: a controlled follow-up study.

Nature and frequency of somatic complaints, severity of anxiety and depression, and nature of psychiatric symptoms and disorders were evaluated in 81 adequately treated cancer patients, disease-free or with residual disease, using a controlled, prospective follow-up design. Patients were included in the index group (n=60) if they had persistent somatic complaints or unexplained nature or severity of somatic complaints, or the control group (n=21), if they did not report somatic complaints. Instruments used for evaluation were the Scale for Assessment of Somatic Symptoms, Hospital Anxiety and Depression Scale, Psychiatric Assessment Schedule, and DSM-III-R. Common somatic complaints in the index group were pain (19%), fatigue (17%), sensory symptoms (30%), and mixed symptoms (27%). Subjects in the index group significantly (p<0.001) more often had depressive or anxiety disorder (19%) and atypical somatoform disorder (15%). Patients were treated appropriately with psychotropic medications and counseling. Follow-up at 4-6 months revealed a significant reduction in the number of somatic symptoms (p<0.001) and anxiety (p<0.001) and depression (p<0.05) scores. The observations confirm that somatic symptoms may persist in cancer patients, which are related to concomitant psychopathology, and require psychiatric intervention.

Depressive Disorder↗

Platelet serotonin concentration in dialysis patients with somatic symptoms of depression.

Platelet serotonin (5-HT) concentration was measured in 65 male and 45 female chronic renal patients on hemodialysis (HD) with different somatic symptoms of depression (crying spells, irritability, sleep disturbance, fatigability, loss of appetite, weight loss, somatic preoccupation and loss of libido), to find out the relationship between the severity of symptoms and platelet 5-HT concentration. Male and female patients had significantly lower platelet 5-HT concentration than 62 male and 38 female healthy subjects. Gender-differences in platelet 5-HT values observed in healthy subjects were not found in patients. Platelet 5-HT concentration differed in the groups of patients with the different scores of particular somatic symptoms (loss of appetite and loss of libido), but was similar in patients with other somatic symptoms. There was no relationship between platelet 5-HT concentration and the severity of somatic symptoms, or between platelet 5-HT concentration and age of the patients. Gender-related differences in the occurrence of somatic symptoms were detected in patients with the different degrees of weight loss, somatic preoccupation and loss of libido. Our results suggest that platelet 5-HT concentration could not be used as a biological marker for the severity of somatic symptoms in chronic renal patients on HD.

Adolescent↗

Predictors of somatic symptoms in depressive disorder.

We explored the relative contribution of potential psychological predictors of somatic symptoms in outpatients with major depressive disorder, including; 1) severity of depression; 2) general anxiety; 3) hypochondriacal worry; 4) somatosensory amplification; and, 5) alexithymia by sampling 100 consecutive outpatients with DSM-IV diagnoses of major depressive disorder attending the psychiatry clinics of general hospitals in Turkey. The subjects were rated by clinicians on depressive symptomatology (Hamilton Depression Rating Scale), and anxiety (Hamilton Anxiety Scale), and completed self-report measures of Hypochondriacal worry (7-item version of the Whiteley Index), the Somatosensory Amplification Scale, and the Toronto Alexithymia Scale. Multivariate models tested the independent contribution of each of the scales to the level of somatic symptoms as measured by a modified version of the SCL-90 somatization scale. At the bivariate level, somatic symptoms were associated with female gender and lower educational level, as well as the Hamilton Depression and Anxiety scales, the Whitely Index, and the Somatosensory Amplification and Alexithymia scales. In multiple regression models incorporating all variables, female gender and higher scores on the anxiety, somatosensory amplification and alexithymia scales all made independent contributions to the level of somatic symptoms and accounted for 54% of the variance. Therefore, somatic symptoms in depression are related to concomitant anxiety, tendency to amplify somatic distress, and difficulty identifying and communicating emotional distress. However, these factors do not account for the tendency for women to report more somatic symptoms.

Adult↗

Somatization and mental health: a comparative study of the idiom of distress hypothesis.

Somatization is the expression of physical symptoms in the absence of medically explained physical illness. As a disproportionate response to psychosocial distress, somatization is usually correlated with depression. According to the idiom of distress hypothesis, the association of somatization and mental health is mitigated when somatizing indirectly expresses, and is understood by others as, emotional distress. Theory and data suggest that collectivistic societies such as South Korea (S.K.), unlike individualistic societies like the U.S. (U.S.), employ an idiom of distress. Multiple measures of physical and mental health were administered to a random sample of S.K. (n=220) and U.S. (n=215) adults. Measurement structures of physical health and mental health were comparable between samples. Individuals in both samples somatized the same number of symptoms, although the U.S. adults expressed those symptoms more frequently. Findings supported the idiom of distress hypothesis. Bivariate and multivariate analyses revealed that the relationship of somatization with mental health depends on culture. Also, the disparity in mental health was greatest and favored the U.S. adults at low levels of somatization, but the disparity in mental health between countries disappeared as somatization increased.

Adult↗

Cortisol and somatization.

Somatization symptoms are frequently associated with depression, anxiety, and feelings of distress. These features interact with the activity of the HPA-axis. Therefore we investigated relationships between somatization symptoms and cortisol. Seventy-seven participants were classified into three groups: somatization syndrome (at least eight physical symptoms from the DSM-IV somatization disorder list), somatization syndrome combined with major depression, and healthy controls. The following data were collected: salivary cortisol at three time points (morning, afternoon, evening), nighttime urinary cortisol, serum cortisol after the dexamethasone suppression test (DST), and psychological variables such as depression, anxiety, somatization, and hypochondriasis. Salivary cortisol showed typical diurnal variations. However, the groups did not differ on any of the cortisol variables. A possible explanation may be counteracting effects of somatization and depression. Exploratory correlational analyses revealed that associations between cortisol and psychopathological variables were time-dependent. DST results correlated with psychological aspects of somatization, but not with the number of somatoform symptoms per se.

Adult↗

Somatic gene mutation and human disease other than cancer.

While the focus of much mutation research is on germ-line mutation, somatic mutation is being found to be important in human disease. Neurofibromatosis 1 and McCune-Albright are disorders which are detected in the skin and other systems. The skin manifestations were essential for the demonstration of somatic mosaicism in neurofibromatosis 1, while analysis of blood DNA demonstrated somatic mutation in neurofibromatosis 2. Incontinentia pigmenti is also a disorder seen in skin and other tissues, but here it is the rare variant of the disorder in males, where it is usually lethal, that involves somatic mosaicism. Paroxysmal nocturnal hemoglobinuria is a disorder of the blood and cell separation of blood elements allows the demonstration of the somatic mosaicism. This review also discusses disorders in which somatic mosaicism, for mutations probably incompatible with life if the mutation had been germ-line, are likely to be involved. These include the Proteus syndrome, which involves both vascular tissues and bones, and two disorders which might be thought of as representing two subtypes of Proteus: Klippel-Trenaunay, which involves vascular tissues, and Maffuci, which involves bones. Embryonic mutations, which create mosaicism for both the soma and germ-line, are being increasingly found in a number of disorders and are discussed more briefly. Finally, reverse mutations involving the soma have been recently found in several disorders and such revertant mutations are also examined. While the review focuses on the clinical importance of somatic mutations, many of the mutations found to date are tabulated. It is too early to see if there is a different pattern of somatic mutation as compared to germ-line mutation. Although the parameters to allow careful quantitation are not yet available, it seems that the frequency of gene mutation in embryonic cells is not markedly different than that in the germ-line.

Fibrous Dysplasia, Polyostotic↗