Dalbergiella welwitschia (Baker) Baker f. alkaloid-rich extracts attenuate liver damage in streptozotocin-induced diabetic rats

This experiment was conducted to evaluate the Dalbergiella welwitschia alkaloid-rich extracts on liver damage in streptozotocin-induced diabetic rats. Hence, to induce diabetes, 45 mg/kg body weight of streptozotocin was intraperitoneally injected into the Wistar rats. Subsequently, 5 % (w/v) of glucose water was given to the induced animals for 24 h. Thus, the animals (48) were grouped into five groups (n = 8), containing normal control (NC), diabetic control (DC), diabetic rats placed on low (50 mg/kg body weight) and high (100 mg/kg body weight) doses of D. welwitschi alkaloid-rich leaf extracts (i.e. DWL and DWH respectively), and diabetic rats administered 200 mg/kg body weight of metformin (MET). The animals were sacrificed on the 21st day of the experiment, blood and liver were harvested, and different liver damage biomarkers were evaluated. The results obtained demonstrated that diabetic rats administered DWL, DWH and MET significantly (p < 0.05) increased hepatic AST, ALT, albumin, SOD, CAT, GSH, and GPX levels when compared to DC with no significant (p > 0.05) different when compared with NC. Also, diabetic rats administered DWL, DWH and MET revealed a significant (p < 0.05) decrease in GGT and MDA levels, as well as, fragmented DNA and protein carbonyl levels when compared to DC with no significant (p > 0.05) different when compared with NC. In addition, histological examination revealed that diabetic rats placed on DWL, DWH and MET normalized the hepatocytes. Consequently, it can be inferred that alkaloid-rich extracts from D. welwitschi leaf could be helpful in improving liver damage associated with diabetes mellitus rats.

Curcuphenol possesses an unusual histone deacetylase enhancing activity that counters immune escape in metastatic tumours

Curcuphenol, a common component of the culinary spices, naturally found in marine invertebrates and plants, has been identified as a novel candidate for reversing immune escape by restoring expression of the antigen presentation machinery (APM) in invasive cancers, thereby resurrecting the immune recognition of metastatic tumours. Two synthetic curcuphenol analogues, were prepared by informed design that demonstrated consistent induction of APM expression in metastatic prostate and lung carcinoma cells. Both analogues were subsequently found to possess a previously undescribed histone deacetylase (HDAC)-enhancing activity. Remarkably, the H3K27ac ChIPseq analysis of curcuphenol-treated cells reveals that the induced epigenomic marks closely resemble the changes in genome-wide pattern observed with interferon-γ, a cytokine instrumental for orchestrating innate and adaptive immunity. These observations link dietary components to modifying epigenetic programs that modulate gene expression guiding poised immunity.

A novel cell-based screen identifies chemical entities that reverse the immune-escape phenotype of metastatic tumours

Genetic and epigenetic events have been implicated in the downregulation of the cellular antigen processing and presentation machinery (APM), which in turn, has been associated with cancer evasion of the immune system. When these essential components are lacking, cancers develop the ability to subvert host immune surveillance allowing cancer cells to become invisible to the immune system and, in turn, promote cancer metastasis. Here we describe and validate the first high-throughput cell-based screening assay to identify chemical extracts and unique chemical entities that reverse the downregulation of APM components in cell lines derived from metastatic tumours. Through the screening of a library of 480 marine invertebrate extracts followed by bioassay-guided fractionation, curcuphenol, a common sesquiterpene phenol derived from turmeric, was identified as the active compound of one of the extracts. We demonstrate that curcuphenol induces the expression of the APM components, TAP-1 and MHC-I molecules, in cell lines derived from both metastatic prostate and lung carcinomas. Turmeric and curcumins that contain curcuphenol have long been utilized not only as a spice in the preparation of food, but also in traditional medicines for treating cancers. The remarkable discovery that a common component of spices can increase the expression of APM components in metastatic tumour cells and, therefore reverse immune-escape mechanisms, provides a rationale for the development of foods and advanced nutraceuticals as therapeutic candidates for harnessing the power of the immune system to recognize and destroy metastatic cancers.

Specific cannabinoids revive adaptive immunity by reversing immune evasion mechanisms in metastatic tumours

Emerging cancers are sculpted by neo-Darwinian selection for superior growth and survival but minimal immunogenicity; consequently, metastatic cancers often evolve common genetic and epigenetic signatures to elude immune surveillance. Immune subversion by metastatic tumours can be achieved through several mechanisms; one of the most frequently observed involves the loss of expression or mutation of genes composing the MHC-I antigen presentation machinery (APM) that yields tumours invisible to Cytotoxic T lymphocytes, the key component of the adaptive cellular immune response. Fascinating ethnographic and experimental findings indicate that cannabinoids inhibit the growth and progression of several categories of cancer; however, the mechanisms underlying these observations remain clouded in uncertainty. Here, we screened a library of cannabinoid compounds and found molecular selectivity amongst specific cannabinoids, where related molecules such as Δ9-tetrahydrocannabinol, cannabidiol, and cannabigerol can reverse the metastatic immune escape phenotype in vitro by inducing MHC-I cell surface expression in a wide variety of metastatic tumours that subsequently sensitizing tumours to T lymphocyte recognition. Remarkably, H3K27Ac ChIPseq analysis established that cannabigerol and gamma interferon induce overlapping epigenetic signatures and key gene pathways in metastatic tumours related to cellular senescence, as well as APM genes involved in revealing metastatic tumours to the adaptive immune response. Overall, the data suggest that specific cannabinoids may have utility in cancer immunotherapy regimens by overcoming immune escape and augmenting cancer immune surveillance in metastatic disease. Finally, the fundamental discovery of the ability of cannabinoids to alter epigenetic programs may help elucidate many of the pleiotropic medicinal effects of cannabinoids on human physiology.

A majority of uninfected adults show preexisting antibody reactivity against SARS-CoV-2

Preexisting cross-reactivity to SARS-CoV-2 occurs in the absence of prior viral exposure. However, this has been difficult to quantify at the population level due to a lack of reliably defined seroreactivity thresholds. Using an orthogonal antibody testing approach, we estimated that about 0.6% of nontriaged adults from the greater Vancouver, Canada, area between May 17 and June 19, 2020, showed clear evidence of a prior SARS-CoV-2 infection, after adjusting for false-positive and false-negative test results. Using a highly sensitive multiplex assay and positive/negative thresholds established in infants in whom maternal antibodies have waned, we determined that more than 90% of uninfected adults showed antibody reactivity against the spike protein, receptor-binding domain (RBD), N-terminal domain (NTD), or the nucleocapsid (N) protein from SARS-CoV-2. This seroreactivity was evenly distributed across age and sex, correlated with circulating coronaviruses' reactivity, and was partially outcompeted by soluble circulating coronaviruses' spike. Using a custom SARS-CoV-2 peptide mapping array, we found that this antibody reactivity broadly mapped to spike and to conserved nonstructural viral proteins. We conclude that most adults display preexisting antibody cross-reactivity against SARS-CoV-2, which further supports investigation of how this may impact the clinical severity of COVID-19 or SARS-CoV-2 vaccine responses.

Antibody reactivity to SARS-CoV-2 is common in unexposed adults and infants under 6 months

BACKGROUND

Pre-existing antibody reactivity against SARS-CoV-2 in unexposed people is a potentially important consideration for COVID-19 severity and vaccine responses. However, it has been difficult to quantify due to a lack of reliable defined background titers in unexposed individuals.

METHODS

We measured IgG against multiple SARS-CoV-2 antigens, SARS-CoV and other circulating coronavirus spike proteins using a highly sensitive multiplex assay, and total SARS-CoV-2 spike-specific antibodies (IgG/M/A) using a commercial CLIA assay in 276 adults from the Vancouver area, Canada between May 17th and June 19th 2020. Reactivity threshold in unexposed individuals were defined comparing to pre-pandemic sera and to sera from infants under 6 months of age.

RESULTS

The seroprevalence from a SARS-CoV-2 exposure, adjusted for false-positive and false-negative test results, was 0.60% in our adult cohort. High antibody reactivity to circulating endemic coronaviruses was observed in all adults and was about 10-fold lower in infants under 6 months. Consistent with a waning of maternal antibodies, reactivity in infants decreased more than 50-fold eight months later. SARS-CoV-2 Spike, RBD, NTD or nucleocapsid antibody reactivity >100-fold above that of older infants was detected in the vast majority of unexposed adults and pre-pandemic sera. This antibody reactivity correlated with titers against circulating coronaviruses, but not with age, sex, or whether adults were healthcare workers.

CONCLUSION

A majority of unexposed adults have pre-existing antibody reactivity against SARS-CoV-2. The lack of similar antibody reactivity in infants where maternal antibodies have waned suggests that this cross-reactivity is acquired, likely from repeated exposures to circulating coronaviruses.

Serpulanines A to C, N-Oxidized Tyrosine Derivatives Isolated from the Sri Lankan Fungus Serpula sp.: Structure Elucidation, Synthesis, and Histone Deacetylase Inhibition

Serpulanines A (1), B (2), and C (3) have been isolated from extracts of the rare Sri Lankan macrofungus Serpula sp. The structures of 1, 2, and 3 were elucidated by a combination of spectroscopic and single-crystal X-ray diffraction analyses. Serpulanines A (1) and B (2) both contain the rare (E)-2-hydroxyimino hydroxamic acid functional group array. A proposed biogenesis for serpulanine B (2) suggests that its (E)-2-hydroxyimino hydroxamic acid moiety arises from a diketopiperazine precursor. Synthetic serpulanine A (1) inhibited class I/II histone deacetylases in murine metastatic lung carcinoma cells with an IC₅₀ of 7 μM.

The awareness of primary caregivers in South Africa of the human rights of their children with intellectual disabilities

BACKGROUND

Besides the right to freedom, human rights can be seen as a basic requirement also for the maintenance of human dignity and the opportunity to thrive - particularly in the case of children with disabilities. It is imperative to explore primary caregivers' awareness of the human rights of their children with intellectual disabilities in view of the role they may play in either facilitating or restricting these rights. This paper explores the awareness of 219 primary caregivers of the human rights of their children with intellectual disabilities.

METHOD

A descriptive survey design was used with a custom-designed questionnaire that employed a deductive content analysis based on the articles of the United Nations Convention on the Rights of a Child. Comparisons were drawn between the awareness of primary caregivers from urban and those from rural areas.

RESULTS

The majority (85.5%) of participants agreed that their child with intellectual disability had rights. Three broad kinds of right were mentioned (in descending order): provision rights, protection rights and participation rights. Participants from both urban and rural areas mentioned education (a provision right) most frequently. However, participants from urban areas were more aware of the different rights that existed than were their counterparts from rural areas.

CONCLUSION

Primary caregivers in both rural and urban areas are aware of the rights of their children with disabilities, although there are significant differences between them.

The Effect of a Non-Powered, Self-Initiated Mobility Program on the Engagement of Young Children with Severe Mobility Limitations in the South African Context

AIM

To determine the effect of a non-powered, self-initiated mobility program on the engagement of young children with severe mobility limitations, in the South African context.

METHODS

A multiple-probe-across-participant design was used. Four children (aged 2-6 years) with severe mobility limitations underwent an intervention that targeted non-powered, self-initiated mobility. The intervention comprised eight sessions over a 2-week period. Engagement was measured during each baseline, intervention and postintervention session using the Individual Child Engagement Record-Revised (ICER-R). The data were presented graphically and analyzed using statistical procedures appropriate for single-subject designs.

RESULTS

Participants demonstrated an improvement in engagement during the time in which non-powered, self-initiated mobility program was introduced. A reciprocal deterioration in nonengagement was also demonstrated. The results of the study are discussed in terms of various intrinsic and extrinsic factors.

CONCLUSIONS

The use of a non-powered, self-initiated mobility program may be effective in improving engagement in some young children with severe mobility limitations.

South African families raising children with autism spectrum disorders: relationship between family routines, cognitive appraisal and family quality of life

BACKGROUND

The purpose of this study was to investigate the relationship between family routines, cognitive appraisal of the impact of autism spectrum disorders (ASD) on the family and family quality of life (FQOL) in families raising children with ASD in South Africa.

METHODS

A sample of 180 families of young children with ASD who were receiving disability-related services in the Gauteng province of South Africa completed a self-administered survey. Structural equation modelling was used to examine the direct relationship between the regularity of family routines and FQOL, and the mediating effect of cognitive appraisal on this relationship.

RESULTS

The results suggested a direct, positive relationship between the regularity of family routines and families' satisfaction with their FQOL. Furthermore, cognitive appraisal of the impact of ASD on the family mediated this relationship in a partial manner.

CONCLUSION

A higher frequency of regular family routines was strongly associated with a higher satisfaction level of FQOL. Also, cognitive appraisal of the impact of ASD acted as a mechanism through which the regularity of family routines influenced FQOL. We discuss the research and clinical implications of these findings.

A discussion of individual variability, in activity-based interventions, using the niche concept

BACKGROUND

Activity-based intervention has been defined as a child-directed, transactional approach that uses logically occurring antecedents and consequences to develop functional and generative skills by embedding intervention of children's individual goals and objectives in routine, planned or child-initiated activities. In this approach, clear goals and objectives that are functional and embedded in a play activities or routines are developed. The teacher mediates the child's environment to facilitate learning with the child directing the teacher on the pace, duration spent on the objective. Learning and development in this framework occur through both a carefully planned environment and adult facilitation. Progress made by a child using this approach focuses on observational data that describe if the child is able to respond in functional and generative ways. While activity-based interventions are usually provided for a group of children, progress is measured by describing individual children's responses. Individual variations in the children's progress, despite exposure to the same interventions are an area that is seldom discussed. This article aims to explore the niche concept and its application to explaining this variation between individuals.

METHODS

Four children participated in this single-subject, multiple-probe study across four participants. A 3-week long activity-based aided language stimulation programme was developed. The effect of the programme was determined by describing the individual participants understanding of the 24 targeted vocabulary items.

RESULTS

The results of the activity-based language programme are presented and the variability among the participants is discussed using the niche concept. The role of the niche concept in individual development is described and the implications thereof are discussed.

CONCLUSIONS

Finally, activity-based intervention research is placed in a systems perspective and possible outcome measures of this intervention are discussed from a multidimensional ecological perspective.

[Thrombolytic treatment of obstructions of mechanical valve prostheses. Apropos of 4 cases and analysis of the literature]

The obstruction of the mechanical valve prothesis (OMVP) is a serious complication. The treatment of this complication was classically surgical. Recently, the thrombolytic treatment was introduced as an alternative approach for patients with high perioperative risk and for those in whom the mechanism of the obstruction is a recently formed thrombus. The authors report four cases of OMVP treated by a thrombolytic agent (Streptokinase, SK, Streptase). Immediate success was obtained in all theses four cases. One late recurrence with fatal issue was noted. All four prostheses were Saint Jude medical (SJM), three in mitral and one in aortic position respectively. The details of the clinical presentation (acute or progressive dyspnea) as well as the contribution of the echocardiography to the diagnosis were presented. The evolution of this therapeutic approach and the international recommendations were reviewed.

Gastric involvement in Waldenstrom macroglobulinemia: CT findings

Waldenstrom macroglobulinemia is a plasma cell dyscrasia that rarely presents with gastrointestinal involvement. We report a case of gastric involvement of Waldenstrom macroglobulinemia detected by CT.

Biological risk factors for sudden death in patients with coronary artery disease and without heart failure

In a study of biological risk factors for sudden death in patients with coronary artery disease, 320 patients were, prospectively, recruited and followed-up over two years. None of the patients had heart failure or recent myocardial infarction. The following variables were recorded: previous acute myocardial infarction, hypertension, smoking habits, ventricular arrhythmia; the angiographic variables included: left ventricular ejection fraction, Jenkins' and mean atherosclerotic scores; lipid profile: cholesterol, triglycerides, high density lipoprotein cholesterol, low density lipoprotein cholesterol, apolipoproteins Al and B; hemostatic profile: fibrinogen, fibrinopeptide A, antithrombin III, factor VIII antigen, factor VIII coagulant, protein C, plasminogen, alpha 2-antiplasmin, euglobulin clot lysis time and tissue plasminogen activator before and after venous occlusion, tissue plasminogen activator inhibitor, platelet factor 4, beta-thromboglobulin. During the follow-up period, 12 of the patients died suddenly. In these patients, ejection fraction was lower: 49 +/- 16% versus 61 +/- 14% for the other patients (P less than 0.02), fibrinogen higher: 3.9 +/- 0.8 g/l versus 3.5 +/- 0.8 for the living patients (P less than 0.05) and protein C lower: 89 +/- 39% versus 111 +/- 39% (P = 0.06) for the other patients. In multivariate analysis: lower ejection fraction (P less than 0.008), older age (P less than 0.03) and lower protein C (P less than 0.01) were correlated with sudden death. Among the patients with coronary artery disease, the raised fibrinogen and the decreased protein C appeared to be risk factors for sudden cardiac death. These alterations reflected a prothrombotic state which might increase the ischemic risk, due to an acute thrombosis, leading to the fatal ventricular arrhythmia. Determination of these hemostatic variables might be a useful adjunct for assessment of the vital prognosis of patients with coronary artery disease, especially the risk of sudden death in addition to other known clinical, electrocardiographic, hemodynamic risk factors. This would also guide both the instigation of complementary investigations and appropriate therapy in such high risk group of patients.