Low-grade systemic inflammation and the workplace.

Background: Psychosocial and physical stressors can elicit the stress response, co-ordinated by interactions between neuroendocrine and inflammatory processes. The central role of the immune system, specifically low-grade systemic inflammation, is sometimes overlooked in work-related stress research.

Objective: To review evidence that work-related psychosocial and physical stressors can stimulate a low-grade systemic inflammation which, through interactions with the neurohormonal systems, may impact on the well-being and productivity of workers.

Pellagra in South Africa from 1897 to 2019: a scoping review.

Objective: Pellagra is a nutritional deficiency disease associated with niacin (vitamin B3) deficiency. The history of pellagra is well documented for Europe and the USA, but less is known about the prevalence in sub-Saharan African countries. This study documents the history of pellagra in South Africa, as diagnosed based on dermatological symptoms.

Physical exercise and the patient with schizophrenia.

Background: Schizophrenia is a severe mental disorder with profound effects on a person's life. In addition to the psychiatric symptoms, patients with schizophrenia generally have multiple somatic comorbidities, such as cardiovascular and metabolic disorders. The general practitioner (GP) is of key importance for the patient's continuous care and holistic wellbeing.

Comparison between plasma neopterin and the urine neopterin:creatinine ratio as inflammatory biomarkers.

Background: Neopterin, a product of cell-mediated immunity, is a non-specific biomarker of inflammation. Plasma/serum is generally the body fluid of choice for neopterin assessment, but urine is often used as it does away with venepuncture. Analysis of urine neopterin is based on collection of a single urine sample and expressed as µmol neopterin/mol creatinine.

Heart Rate Variability and Academic Performance of First-Year University Students.

Background: Heart rate variability (HRV) measures have been shown to be positively associated with cognitive processing, while a positive association between cognitive processing and academic performance has been demonstrated.

Objectives: To determine whether resting HRV or HRV marker response to either a cognitive or an orthostatic challenge is significantly associated with a first-year university student's academic performance.

Method: HRV markers used in the study included total power (TP) as a measure of overall HRV and the root mean square of successive differences (RMSSD) as a measure of parasympathetic influence on the heart.

Validity of Commonly Used Heart Rate Variability Markers of Autonomic Nervous System Function.

Background: Despite strong reservations regarding the validity of a number of heart rate variability (HRV) measures, these are still being used in recent studies.

Aims: We aimed to compare the reactivity of ostensible sympathetic HRV markers (low and very low frequency [LF and VLF]) to that of electrodermal activity (EDA), an exclusively sympathetic marker, in response to cognitive and orthostatic stress, investigate the possibility of LF as a vagal-mediated marker of baroreflex modulation, and compare the ability of HRV markers of parasympathetic function (root mean square of successive differences [RMSSD] and high frequency [HF]) to quantify vagal reactivity to cognitive and orthostatic stress.

Results: None of the purported sympathetic HRV markers displayed a reactivity that correlated with electrodermal reactivity.

A case study of two adolescent-parent pairs describing the association between vagal tone and social-emotional adjustment during a Positive Cognitive Behaviour Therapy Programme.

Objective: A case study describing the association between vagal tone and social-emotional adaptation in two distressed adolescent-parent (A-P) pairs during a Positive Cognitive Behaviour Therapy Programme (P-CBTP).

Methods: Two A-P pairs completed a P-CBTP with pre- and post-intervention biosocial-emotional assessments; weekly training sessions over 7 weeks to develop individual strengths, new adaptive cognitions, positive discipline skills, optimism and knowledge on age-appropriate developmental expressions; augmented by moderate physical activity. Resting vagal tone and vagal reactivity were assessed by time-domain measures of vagal activity (RMSSD).

Allostatic load and heart rate variability as health risk indicators.

Background: Uncertainty often exists about the comparability of results obtained by different health risk indicator systems.

Objectives: To compare two health risk indicator systems, i.e, allostatic load and heart rate variability (HRV).

Cynicism as subscale of burnout.

Background: Cynicism, as a personality trait, has adverse effects on health. The question was asked whether cynical attitudes that develop due to work-related stress correlate with stress levels and whether it has a negative influence on health.

Objectives: To investigate associations of the cynicism subscale scores of the Maslach Burnout Inventory-General Survey (MBI-GS) with levels of stress, anxiety, questionnaire-based physical health and with a number of physiological health risk indicators.

Tryptophan depletion in context of the inflammatory and general nutritional status of a low-income South African HIV-infected population.

Background: The essential amino acid tryptophan cannot be synthesised in the body and must be acquired through dietary intake. Oxidation of tryptophan, due to immune induction of the enzyme indoleamine 2,3-dioxygenase (IDO), is considered to be the main cause of tryptophan depletion in HIV infection and AIDS. We examined plasma tryptophan levels in a low-income sub-Saharan HIV-infected population and compared it to that of developed countries.

EEG Brain Wave Activity at Rest and during Evoked Attention in Children with Attention-Deficit/Hyperactivity Disorder and Effects of Methylphenidate.

Objective: The aim of this study was to assess baseline EEG brain wave activity in children with attention-deficit/hyperactivity disorder (ADHD) and to examine the effects of evoked attention and methylphenidate on this activity.

Method: Children with ADHD (n = 19) were tested while they were stimulant free and during a period in which they were on stimulant (methylphenidate) medication. Control subjects (n = 18) were tested once.

The kynurenine pathway activities in a sub-Saharan HIV/AIDS population.

Background: Tryptophan is an essential amino acid for the synthesis of proteins and important metabolites such as serotonin, melatonin, tryptamine and niacin. After protein synthesis, more than 90 % of tryptophan catabolism occurs along the kynurenine pathway. The inflammation-inducible enzyme indoleamine 2,3 dioxygenase (IDO) is responsible for the first rate-limiting step in the kynurenine pathway, i.

A non-specific biomarker of disease activity in HIV/AIDS patients from resource-limited environments.

Background: A general non-specific marker of disease activity that could alert the clinician and prompt further investigation would be of value in patients with HIV/AIDS, especially in resource limited environments.

Objective: To investigate the potential of neopterin as non-specific biomarker in patients with advanced HIV/AIDS.

Methods: Cross-sectional study in 105 HIV positive patients (75 on highly active antiretroviral treatment (HAART).

Antidepressants may lead to a decrease in niacin and NAD in patients with poor dietary intake.

The term niacin is the generic name for the two compounds nicotinic acid and nicotinamide, the major dietary precursors for two important coenzymes, nicotinamide adenine dinucleotide (NAD) and its phosphorylated form, NADP. Niacin is important for the maintenance of cellular integrity and energy production and is involved in more than 500 intracellular reactions. Deficiencies of niacin may contribute to neuropsychiatric and neurodegenerative disorders.

Heart rate variability assessment of the effect of physical training on autonomic cardiac control.

Background: The effect of exercise interventions on autonomic nervous system (ANS) control of the heart by heart rate variability (HRV) is often investigated in just one position. It was hypothesized that results of exercise-induced changes on ANS are dependent on body position and that it is possible to distinguish between exercise induced changes in vagal and sympathetic influence by taking measurements in different body positions.

Methods: One hundred eighty-three (male = 100, female = 83) healthy volunteers, between 18 and 22 years, participated in a prospective twelve week medium to high intensity exercise intervention study with a self-control design.

Expression of the H- and L-subunits of ferritin in bone marrow macrophages of patients with osteoarthritis.

Osteoarthritis is a disease characterized by an increase in the production of reactive oxygen species (ROS) in afflicted joints. Excess iron, due to its role in the production of ROS and crystal deposition in the joints, is implicated in the disease progression of osteoarthritis. Ferritin is a major regulator of the bioavailability of iron, and its functions are determined largely by the combination of H- and L-subunits present in its outer protein shell.

Importance of tachogram length and period of recording during noninvasive investigation of the autonomic nervous system.

Background: Various disciplines use quantification of heart rate variability (HRV) as an indicator of autonomic function without recognizing the importance of using standardized methodologies. The aim of this study was to assess the influence of tachogram length and period of recording on HRV indicator values.

Methods: To test the influence of the length of the recording time, HRV indicator values calculated from 180, 300, 420, and 600 seconds recording periods (supine and standing) were compared.

Stimulants and growth in children with attention-deficit/hyperactivity disorder.

Initial suggestions that suppression of growth may be an intrinsic characteristic of attention-deficit/hyperactivity disorder (ADHD) have now largely been disproven. Although controversy persists regarding the possible negative effect of adrenergic stimulants on growth in children with ADHD, the consensus that appears to be reached in the scientific literature is that stimulant usage may cause a manageable attenuation of growth in these children. Since it is known that stimulants increase the amount of dopamine and noradrenaline in the synapse, this writing suggests that these increases in dopamine and noradrenaline are responsible for the growth attenuation in these children.

Autonomic correlates at rest and during evoked attention in children with attention-deficit/hyperactivity disorder and effects of methylphenidate.

Objective: The aim of this study was to assess autonomic nervous system functioning in children with attention-deficit/hyperactivity disorder (ADHD) and to examine the effects of methylphenidate and focussed attention.

Method: Children with ADHD (n = 19) were tested while they were stimulant free and during a period in which they were on stimulants. On both occasions, autonomic nervous system functioning was tested at baseline and during focussed attention.

The effect of sympathomimetic medication on cardiovascular functioning of children with attention-deficit/hyperactivity disorder.

Objective: The aim of this study was to investigate the effects of sympathomimetic medication on the cardiovascular system of children with attention-deficit/hyperactivity disorder (ADHD).

Methods: Cardiovascular functioning of children with ADHD (n = 19) was tested while the children were stimulant free and during a period in which they were on stimulant medication. Electrocardiograms (ECGs) were obtained by means of a Schiller CardioLaptop AT-110 ECG recorder using the standard 12-lead cable positioning for a resting ECG.

Relationship between exercise capacity and heart rate variability: supine and in response to an orthostatic stressor.

The study investigated whether supine-measured HRV indicators, and/or HRV indicators measured during orthostatic stress are related to conventional measures of exercise and performance ability such as VO(2max). Only two significant correlations (p<0.05) out of 30 tests were found between supine-determined HRV indicators and conventional measures.

Physicians' difficulty with emergency department patients is related to patients' attachment style.

Doctors experience 10-20 percent of patient interactions as being personally difficult, but the sources of difficulty are incompletely understood. In particular, physician-perceived difficulty has not been studied from the perspective of an established model of interpersonal relationships. Our objective was to determine whether a relationship exists between patients' attachment style and the degree of difficulty experienced by their attending physician in an Emergency Department in Pretoria, South Africa.

Non-termination of sickness behavior as precipitating factor for mental disorders.

Sickness behavior can be defined as a combination of coordinated behavioral and physiological changes that develop in response to any condition that elicits pro-inflammatory activity. It is an adaptational homeostasis initiated by the influence of pro-inflammatory cytokines on central nervous system neurohormonal functioning. This paper introduces the concept of non-termination of sickness behavior as a potential threat to mental health.