A feasibility study of microwave therapy for precancerous actinic keratosis.

BACKGROUND: Actinic keratosis (AK) is a common premalignant skin lesion that can progress to cutaneous squamous cell carcinoma (cSCC). Microwave therapy is an established cancer treatment and has been used for plantar viral warts. OBJECTIVES: To evaluate the efficacy and feasibility of microwave as a treatment for AK. METHODS: Stage I was a dose-setting study, in which seven participants had the dielectric properties of 12 thick and 22 thin AKs assessed for optimization of the microwave dose used for treatment in Stage II. Stage II was a randomized, internally controlled trial evaluating 179 AKs in 11 patients (93 treated, 86 untreated controls) on the scalp/forehead or dorsal hand. Participants received one treatment initially and a repeat treatment to unresolved AKs at week 4. The response was assessed at six visits over 4 months. The primary outcome was partial or complete resolution of the treated AKs. RESULTS: A significantly higher proportion of treated AK areas responded than untreated (90% vs. 15%; P < 0·001). Thin AKs were more responsive than thick AKs. The site did not affect efficacy. Pain was severe, but brief (80% reported pain lasting 'a few seconds only'). Adverse effects were minimal (erythema, n = 6; flaking, n = 3; itch, n = 3). All participants who would chose microwave therapy over their current treatment cited the shorter discomfort period. CONCLUSIONS: Microwave therapy is a portable, safe and effective treatment for AK. An easy-to-deliver, acceptable therapy for AK is attractive as a prevention strategy. While these results are promising, a larger randomized controlled trial is needed against an effective comparator to confirm clinical efficacy and patient acceptability. What is already known about this topic? Actinic keratoses (AKs) are common precancerous skin lesions. Successful treatment of AK can prevent cutaneous squamous cell carcinoma (cSCC). Most topical therapies for AK require repeated application over weeks and drive local skin inflammation, leading to poor compliance. An easy-to-deliver and effective treatment for AK, suitable for use in primary care, could reduce cSCC. What does this study add? Microwave therapy is a feasible, effective treatment for AK. Ninety per cent of treated AKs showed full or partial resolution at 120 days post-treatment. Microwave therapy was painful, but the pain was short-lived (seconds) and this short discomfort period was cited as the main reason that microwave was preferred to their current treatment.

Neural Control of Vascular Function in Skeletal Muscle.

The sympathetic nervous system represents a fundamental homeostatic system that exerts considerable control over blood pressure and the distribution of blood flow. This process has been referred to as neurovascular control. Overall, the concept of neurovascular control includes the following elements: efferent postganglionic sympathetic nerve activity, neurotransmitter release, and the end organ response. Each of these elements reflects multiple levels of control that, in turn, affect complex patterns of change in vascular contractile state. Primarily, this review discusses several of these control layers that combine to produce the integrative physiology of reflex vascular control observed in skeletal muscle. Beginning with three reflexes that provide somewhat dissimilar vascular patterns of response despite similar changes in efferent sympathetic nerve activity, namely, the baroreflex, chemoreflex, and muscle metaboreflex, the article discusses the anatomical and physiological bases of postganglionic sympathetic discharge patterns and recruitment, neurotransmitter release and management, and details of regional variations of receptor density and responses within the microvascular bed. Challenges are addressed regarding the fundamentals of measurement and how conclusions from one response or vascular segment should not be used as an indication of neurovascular control as a generalized physiological dogma. Whereas the bulk of the article focuses on the vasoconstrictor function of sympathetic neurovascular integration, attention is also given to the issues of sympathetic vasodilation as well as the impact of chronic changes in sympathetic activation and innervation on vascular health. © 2016 American Physiological Society.

The internal consistency and factorial structure of behaviors judged to be associated with DSM-III personality disorders.

The authors examined the internal consistency and factorial structure of behavioral criteria for assessing personality disorders. Most sets of criteria were internally consistent, but items relating to different disorders showed substantial intercorrelations. Factor analysis identified specific traits rather than actual disorders.

Genetic and environmental contributions to dimensions of personality disorder.

OBJECTIVE: The authors estimated the heritability of the basic dimensions of personality disorder and the relative proportions of the variance attributable to genetic and environmental sources. METHOD: The subjects were 175 volunteer twin pairs (90 monozygotic and 85 dizygotic) from the general population. Each twin completed the Dimensional Assessment of Personality Pathology, a questionnaire that assesses 18 dimensions of personality disorder. The questionnaire was developed on the basis of factor analytic studies that identified a stable structure underlying personality disorders in clinical and nonclinical subjects. Structural equation model-fitting methods were used to estimate the influence of additive genetic, common environmental, and unique environmental effects. RESULTS: The estimates of broad heritability ranged from 0%, for conduct problems, to 64%, for narcissism. Behaviors associated with submissiveness and attachment problems had low heritability. For most dimensions, the best-fitting model was one that specified additive genetic and unique environmental effects. CONCLUSIONS: These results are similar to those reported for normal personality and suggest a continuity between normal and disordered personality.

Validation of the survey of work styles: a profile measure of the type A behaviour pattern.

The present study compares the Type A classification accuracy of the Jenkins Activity Survey (JAS), The Framingham Type A Scale, and a new Type A behaviour pattern (TABP) measure. The Survey of Work Styles (SWS), a self-report measure of the TABP, was developed using a construct approach to scale construction. It consists of six content scales. Impatience, Anger, Work Involvement, Time Urgency, Job Dissatisfaction and Competitiveness. In addition to the six content scales, a seventh scale, Scale A, is comprised of items empirically selected to relate to the Rosenman Structured Interview. In the present study the SWS was found to be significantly related to both the JAS, and the Framingham Type A Scale in a sample of 163 business managers. Median reliability of the SWS subscales was 0.82, and for the total scale 0.90. Discriminant function analysis using cross validational jackknifing procedures resulted in a classification accuracy of 83% of the Type A managers in relation to the Structured Interview. Classification using the SWS was found to correlate significantly higher with the Structured Interview than did either classification with the JAS or with the Framingham Type A Scale. Modal profile analysis yielded three independent bipolar typal dimensions, indicating that a single dimension or classification of the TABP represents an oversimplification of a complex behaviour pattern. These results support the reconceptualization of the TABP in terms of distinct facets and profile patterns.

Acute head-down tilt decreases the postexercise resting threshold for forearm cutaneous vasodilation.

The purpose of this study was to evaluate the role of baroreceptor control on the postexercise threshold for forearm cutaneous vasodilation. On four separate days, six subjects (1 woman) were randomly exposed to 65 degrees head-up tilt and to 15 degrees head-down tilt during a No-Exercise and Exercise treatment protocol. Under each condition, a whole body water-perfused suit was used to regulate mean skin temperature (T(sk)) in the following sequence: 1) cooling until the threshold for vasoconstriction was evident; 2) heating ( approximately 7.0 degrees C/h) until vasodilation occurred; and 3) cooling until esophageal temperature (T(es)) and (T(sk)) returned to baseline values. The Exercise treatment consisted of 15 min of cycling exercise at 70% maximal O(2) uptake, followed by 15 min of recovery in the head-up tilt position. The No-Exercise treatment consisted of 30 min resting in the head-up tilt position. After the treatment protocols, subjects were returned to their pretreatment condition, then cooled and warmed again consecutively. The calculated T(es) threshold for cutaneous vasodilation increased 0.24 degrees C postexercise during head-up tilt (P < 0.05), whereas no difference was measured during head-down tilt. In contrast, sequential measurements without exercise demonstrate a time-dependent decrease for head-up tilt (0.17 degrees C) and no difference for head-down tilt. Pretreatment thresholds were significantly lower during head-down tilt compared with head-up tilt. We have shown that manipulating postexercise venous pooling by means of head-down tilt, in an effort to reverse its impact on baroreceptor unloading, resulted in a relative lowering of the resting postexercise elevation in the T(es) for forearm cutaneous vasodilation.

Factorial structure of traits delineating personality disorders in clinical and general population samples.

Categorical and dimensional models for classifying personality disorders were evaluated by comparing the structure of personality pathology in a clinical sample (n = 158) with the structure in a general population sample (n = 274). Subjects completed 100 personality scales. Separate factor analyses revealed similar structures in the 2 samples. An underlying structure in a combined sample showed limited agreement with the concepts of the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1987). Fifteen factors were retained: Generalized Distress, Rejection, Restricted Expression, Compulsivity, Stimulus Seeking, Insecure Attachment, Diffidence, Intimacy Problems, Oppositionality, Interpersonal Disesteem, Conduct Problems, Cognitive Dysfunction, Affective Reactivity, Narcissism, and Social Apprehensiveness. The results are consistent with a dimensional representation of personality disorder.

Categorical distinctions in the study of personality disorder: implications for classification.

This article discusses the historical underpinnings of psychiatric classification and examines empirical evidence relevant to (a) whether personality disorders are distinct from each other and from normal personality and (b) whether personality disorders should be classified separately from other mental disorders. At the phenotypic level, research evidence strongly supports the use of a dimensional model to delineate personality disorders; evidence about their genotypic representation is less conclusive though still supportive. Neither empirical nor rational arguments indicate strong justification for separating personality disorders from other mental disorders, as has been done in both the third and fourth editions of the Diagnostic and Statistical Manual of Mental Disorders. Distinctions between abnormal and disordered personality are considered, and suggestions are made for more satisfactory diagnostic classificatory schemes.

Chronic parenting stress: moderating versus mediating effects of social support.

The present study contrasted the widely cited "buffer" model of social support with an alternative mediator model. Distinctions were drawn between the functions of social support under chronic vs. acute stress conditions, and between situation-specific stressors and major life events. Ongoing parenting stress was assessed in 96 mothers of deaf children and 118 matched controls. Tests of the competing models showed no moderating effects for social support. However, path analyses suggested that social support mediated the relationship between stressors and outcomes. Chronic parenting stress was associated with lowered perceptions of emotional support, and greater symptoms of depression and anxiety. Furthermore, parenting stress accounted for a substantial proportion of the variance in psychological distress scores in contrast to life event stress, which was only weakly related to psychological outcomes. The implications of mediational models for understanding adaptation to chronic stress are discussed.

Dimensions of psychopathology among alcoholic patients.

Responses of hospitalized alcoholics to the Minnesota Multiphasic Personality Inventory and the Differential Personality Inventory were intercorrelated and factor analyzed. Considerable heterogeneity of psychopathology within the sample was found.

Identification of a coronary-prone profile for business managers: comparison of three approaches to Type A assessment.

This study compares three approaches to Type A assessment for identifying a coronary-prone profile for business managers. The Survey of Work Styles (SWS), a profile measure of the Type A behavior pattern, was compared with the Structured Interview (SI), a categorical measure, and with the Jenkins Activity Survey (JAS) and Framingham Type A Scale, both continuous measures. The blood pressure, heart rate, and cardiac effort of 163 middle-aged male business managers (107 of whom were classified as Type A by the SI) were assessed during the SI. Neither the classification by the SI of the subjects into Type A and non-Type A groups nor Type A1, A2, X, B3, and B4 revealed differences in physiological arousal. Similarly, no relationship was found between physiological variables and Type A behavior that was assessed on a continuum by the JAS or Framingham Type A Scale. When business managers were classified by the SWS according to their pattern of Type A components, however, the results showed that men high on Anger but low on Competitiveness and Job Dissatisfaction had significantly higher levels of systolic blood pressure during the SI. The importance of recognizing individual differences in the expression of Type A behavior when assessing coronary-prone physiological reactivity is discussed.

Contraction-evoked vasodilation and functional hyperaemia are compromised in branching skeletal muscle arterioles of young pre-diabetic mice.

AIM: To investigate the effects of pre-diabetes on microvascular network function in contracting skeletal muscle. We hypothesized that pre-diabetes compromises contraction-evoked vasodilation of branching second-order (2A), third-order (3A) and fourth-order (4A) arterioles, where distal arterioles would be affected the greatest. METHODS: Intravital video microscopy was used to measure arteriolar diameter (in 2A, 3A and 4A) and blood flow (in 2A and 3A) changes to electrical field stimulation of the gluteus maximus muscle in pre-diabetic (The Pound Mouse, PD) and control (c57bl6, CTRL) mice. RESULTS: Baseline diameter and blood flow were similar between groups (2A: ~20 µm, 3A: ~14 µm and 4A: ~8 µm; 2A: ~1 nL s(-1) and 3A: ~0.5 nL s(-1) ). Single tetanic contraction (100 Hz; 200, 400, 800 ms duration) evoked rapid-onset vasodilation (ROV) and blood flow responses that were blunted by ~50% and up to 81%, respectively, in PD vs. CTRL (P < 0.05). The magnitude of ROV was up to 2-fold greater at distal arterioles (3A and 4A) vs. proximal arterioles (2A) in CTRL; however, in PD, ROV of only 4A was greater than 2A (P < 0.05). Rhythmic contraction (2 and 8 Hz, 30 s) evoked vasodilatory and blood flow responses that were also attenuated by ~50% and up to 71%, respectively, in PD vs. CTRL (P < 0.05). The magnitude of vasodilatory responses to rhythmic contraction was also up to 2.5-fold greater at 4A vs. 2A in CTRL; however spatial differences in vasodilation across arteriolar branch orders was disrupted in PD. CONCLUSIONS: Arteriolar dysregulation in pre-diabetes causes deficits in contraction-evoked dilation and blood flow, where greatest deficits occur at distal arterioles.