Longitudinal Impacts of Precision Greenness on Alzheimer's Disease.

BACKGROUND: The potential for greenness as a novel protective factor for Alzheimer's disease (AD) requires further exploration. OBJECTIVES: This study assesses prospectively and longitudinally the association between precision greenness - greenness measured at the micro-environmental level, defined as the Census block - and AD incidence. DESIGN: Older adults living in consistently high greenness Census blocks across 2011 and 2016 were compared to those living in consistently low greenness blocks on AD incidence during 2012-2016. SETTING: Miami-Dade County, Florida, USA. PARTICIPANTS: 230,738 U.S. Medicare beneficiaries. MEASUREMENTS: U.S. Centers for Medicare and Medicaid Services Chronic Condition Algorithm for AD based on ICD-9 codes, Normalized Difference Vegetation Index, age, sex, race/ethnicity, neighborhood income, and walkability. RESULTS: Older adults living in the consistently high greenness tertile, compared to those in the consistently low greenness tertile, had 16% lower odds of AD incidence (OR=0.84, 95% CI: 0.76-0.94, p=0.0014), adjusting for age, sex, race/ethnicity, and neighborhood income. Age, neighborhood income and walkability moderated greenness' relationship to odds of AD incidence, such that younger ages (65-74), lower-income, and non-car dependent neighborhoods may benefit most from high greenness. CONCLUSIONS: High greenness, compared to low greenness, is associated with lower 5-year AD incidence. Residents who are younger and/or who reside in lower-income, walkable neighborhoods may benefit the most from high greenness. These findings suggest that consistently high greenness at the Census block-level, may be associated with reduced odds of AD incidence at a population level.

Correlation between carotid intima-media thickness and patient outcomes in coronary artery disease in central South Africa.

OBJECTIVES: Carotid intima-medial thickness (CIMT) is a non-invasive tool used to detect atherosclerosis and diagnose cardiovascular disease. This study aimed to determine whether pre-operative CIMT measurements correlated with intra- and postoperative outcomes in patients with acute coronary syndrome (ACS) undergoing coronary artery bypass graft (CABG) surgery. METHODS: This retrospective, analytical cohort included 89 patients diagnosed with ACS who received CABG surgery. Patients were divided into two cohorts: group 1: normal CIMT < 0.07 cm and group 2: abnormal CIMT ≥ 0.07 cm. B-mode ultrasound was used to measure the CIMT in all patients. Pre-, intra- and postoperative data and complications were recorded for each patient. RESULTS: The study included 77 (86.5%) males and 12 (13.5%) females. Pre-operative mean body mass index was significantly higher (p = 0.03) in group 2 than in group 1. Group 2 had a significantly increased incidence of diabetes (p = 0.008) and hypertension (p = 0.009), and increased NT-proBNP levels (p = 0.02). Intra- and postoperative outcomes between the groups were comparable, with no significant differences. CONCLUSION: The study showed no correlation between abnormal CIMT and increased adverse intra- and postoperative patient outcomes. Therefore, the results of this study show CIMT should not be considered a tool to predict adverse events in patients undergoing CABG surgery.

Outcomes of single-ventricle physiology in central South Africa.

INTRODUCTION: Single-ventricle physiology is a critical cardiac condition requiring early diagnosis and intervention. The objectives of this study were to report on the management and outcomes of patients diagnosed with single-ventricle physiology in central South Africa. METHODS: This study was a retrospective, observational analysis of patients presenting with single-ventricle physiology at the Universitas Academic Hospital in central South Africa between November 1997 and June 2021. RESULTS: Patients were referred from the Free State (54%) and Northern Cape (29%) provinces and Lesotho. One hundred and fifty-four patients presented with single-ventricle physiology: 114 received interventions and 40 were not eligible for intervention. Patients presented for the first time at a median age of 34.5 days, with patients from nearby districts presenting within a few days of birth. However, patients from outlying areas presented much later. Eighty-seven patients received systemic-to-pulmonary artery shunting or pulmonary artery banding. Sixty-three patients proceeded to bidirectional Glenn procedures, and 30 patients (26%) had full palliation to Fontan. Twenty-one patients died after stage 1, six after the Glenn procedure and two after the Fontan procedure. Overall, 34 (29.8%) patients were lost to follow up. CONCLUSION: Patients in our study presented late and follow up of these patients was a challenge. The highest mortality rate occurs during the first stage of palliation. Outcomes from this study are comparable to other sub-Saharan studies.

Change in nuclear DNA content and pollen size with polyploidisation in the sweet potato (Ipomoea batatas, Convolvulaceae) complex.

Genome size evolution and its relationship with pollen grain size has been investigated in sweet potato (Ipomoea batatas), an economically important crop which is closely related to diploid and tetraploid species, assessing the nuclear DNA content of 22 accessions from five Ipomoea species, ten sweet potato varieties and two outgroup taxa. Nuclear DNA amounts were determined using flow cytometry. Pollen grains were studied using scanning and transmission electron microscopy. 2C DNA content of hexaploid I. batatas ranged between 3.12-3.29 pg; the mean monoploid genome size being 0.539 pg (527 Mbp), similar to the related diploid accessions. In tetraploid species I. trifida and I. tabascana, 2C DNA content was, respectively, 2.07 and 2.03 pg. In the diploid species closely related to sweet potato e.g. I. ×leucantha, I. tiliacea, I. trifida and I. triloba, 2C DNA content was 1.01-1.12 pg. However, two diploid outgroup species, I. setosa and I. purpurea, were clearly different from the other diploid species, with 2C of 1.47-1.49 pg; they also have larger chromosomes. The I. batatas genome presents 60.0% AT bases. DNA content and ploidy level were positively correlated within this complex. In I. batatas and the more closely related species I. trifida, the genome size and ploidy levels were correlated with pollen size. Our results allow us to propose alternative or complementary hypotheses to that currently proposed for the formation of hexaploid Ipomoea batatas.

Evidence of early defects in Cajal-Retzius cell localization during brain development in a mouse model of dystroglycanopathy.

AIMS: The secondary dystroglycanopathies represent a heterogeneous group of congenital muscular dystrophies characterized by the defective glycosylation of alpha dystroglycan. These disorders are associated with mutations in at least 17 genes, including Fukutin-related protein (FKRP). At the severe end of the clinical spectrum there is substantial brain involvement, and cobblestone lissencephaly is highly suggestive of these disorders. The precise pathogenesis of this phenotype has, however, remained unclear with most attention focused on the disruption to the radial glial scaffold. Here, we set out to investigate whether lesions are apparent prior to the differentiation of the radial glia. METHODS: A detailed investigation of the structural brain defects from embryonic day 10.5 (E10.5) up until the time of birth (P0) was undertaken in the Fkrp-deficient mice (FKRPKD ). Reelin, and downstream PI3K/Akt signalling pathways were analysed using Western blot. RESULTS: We show that early basement membrane defects and neuroglial ectopia precede radial glial cell differentiation. Furthermore, we identify mislocalization of Cajal-Retzius cells which nonetheless is not associated with any apparent disruption to the reelin, and downstream PI3K/Akt signalling pathways. CONCLUSIONS: These observations identify Cajal-Retzius cell mislocalization as an early event during the development of cortical defects thereby identifying an earlier onset and more complex pathogenesis than originally reported for the secondary dystroglycanopathies. Overall this study provides new insight into central nervous system involvement in this group of diseases.

Transgenic Rescue of the LARGEmyd Mouse: A LARGE Therapeutic Window?

LARGE is a glycosyltransferase involved in glycosylation of α-dystroglycan (α-DG). Absence of this protein in the LARGEmyd mouse results in α-DG hypoglycosylation, and is associated with central nervous system abnormalities and progressive muscular dystrophy. Up-regulation of LARGE has previously been proposed as a therapy for the secondary dystroglycanopathies: overexpression in cells compensates for defects in multiple dystroglycanopathy genes. Counterintuitively, LARGE overexpression in an FKRP-deficient mouse exacerbates pathology, suggesting that modulation of α-DG glycosylation requires further investigation. Here we demonstrate that transgenic expression of human LARGE (LARGE-LV5) in the LARGEmyd mouse restores α-DG glycosylation (with marked hyperglycosylation in muscle) and that this corrects both the muscle pathology and brain architecture. By quantitative analyses of LARGE transcripts we also here show that levels of transgenic and endogenous LARGE in the brains of transgenic animals are comparable, but that the transgene is markedly overexpressed in heart and particularly skeletal muscle (20-100 fold over endogenous). Our data suggest LARGE overexpression may only be deleterious under a forced regenerative context, such as that resulting from a reduction in FKRP: in the absence of such a defect we show that systemic expression of LARGE can indeed act therapeutically, and that even dramatic LARGE overexpression is well-tolerated in heart and skeletal muscle. Moreover, correction of LARGEmyd brain pathology with only moderate, near-physiological LARGE expression suggests a generous therapeutic window.

In vivo micronucleus studies with 6 titanium dioxide materials (3 pigment-grade & 3 nanoscale) in orally-exposed rats.

Six pigment-grade (pg) or ultrafine (uf)/nanoscale (anatase and/or rutile) titanium dioxide (TiO2) particulates were evaluated for in vivo genotoxicity (OECD 474 Guidelines) in male and female rats by two different laboratories. All test materials were robustly characterized. The BET surface areas of the pg and uf samples ranged from 7 to 17 m(2)/g and 50 to 82 m(2)/g respectively. The materials were assessed for induction of micronuclei and toxicity in bone marrow by analyzing peripheral blood reticulocytes (RETs) by flow cytometry. Single oral gavage doses of 500, 1000 or 2000 mg/kg body weight (bw) of each material were implemented with concurrent negative (water) and positive controls (cyclophosphamide). Approximately 48 and 72 h after exposure, blood samples were collected and 20,000 RETs per animal were analyzed. For each of the six tests, there were no biologically or toxicologically relevant increases in the micronucleated RET frequency in any TiO2 exposed group at either time point at any dose level. In addition, there were a lack of biologically relevant decreases in %RETs among total erythrocytes. All six TiO2 test substances were negative for in vivo genotoxicity effects; however, it is noted that the exposure to target tissues was likely negligible. One pigment grade and one ultrafine material each were evaluated for potential systemic exposure/uptake from the gastrointestinal tract by analysis of TiO2 into blood and liver. No significant increases in TiO2 over controls were measured in blood (48 or 72 h) or liver (72 h) following exposures to 2000 mg/kg bw TiO2. These data indicate that there was no absorption of the test material from the gastrointestinal tract into the blood circulation and the lack of genotoxic effects is therefore attributed to a lack of exposure due to the inability of the test material to migrate from the gastrointestinal tract into the blood and then into target tissues.

Developmental toxicity studies with 6 forms of titanium dioxide test materials (3 pigment-different grade & 3 nanoscale) demonstrate an absence of effects in orally-exposed rats.

Six different commercial forms and sizes of titanium dioxide particles were tested in separate developmental toxicity assays. The three pigment-grade (pg) or 3 ultrafine (uf)/nanoscale (anatase and/or rutile) titanium dioxide (TiO2) particle-types were evaluated for potential maternal and developmental toxicity in pregnant rats by two different laboratories. All studies were conducted according to OECD Guideline 414 (Prenatal Developmental Toxicity Study). In addition, all test materials were robustly characterized. The BET surface areas of the pg and uf samples ranged from 7 to 17 m(2)/g and 50-82 m(2)/g respectively (see Table 1). The test substances were formulated in sterile water. In all of the studies, the formulations were administered by oral gavage to time-mated rats daily beginning around the time of implantation and continuing until the day prior to expected parturition. In 3 of the studies (uf-1, uf-3, & pg-1), the formulations were administered to Crl:CD(SD) rats beginning on gestation day (GD) 6 through GD 20. In 3 additional studies (uf-2, and pg-2, pg-3 TiO2 particles), the formulations were administered to Wistar rats beginning on GD 5 through 19. The dose levels used in all studies were 0, 100, 300, or 1000 mg/kg/day; control group animals were administered the vehicle. During the in-life portions of the studies, body weights, food consumption, and clinical observations before and after dosing were collected on a daily basis. All dams were euthanized just prior to expected parturition (GD 21 for Crl:CD(SD) rats and GD 20 for Wistar rats). The gross necropsies included an examination and description of uterine contents including counts of corpora lutea, implantation sites, resorptions, and live and dead fetuses. All live fetuses were sexed, weighed, and examined externally and euthanized. Following euthanasia, fresh visceral and head examinations were performed on selected fetuses. The fetal carcasses were then processed and examined for skeletal alterations. There was no evidence of maternal or developmental toxicity at any dose level tested in any of the six studies. Based on these results, the no-observed-adverse-effect level (NOAEL) for titanium dioxide was 1000 mg/kg/day, the highest administered dose, in both the Sprague-Dawley (Crl:CD(SD) and Wistar rat strains.

Acute and subchronic oral toxicity studies in rats with nanoscale and pigment grade titanium dioxide particles.

Data generated using standardized testing protocols for toxicity studies generally provide reproducible and reliable results for establishing safe levels and formulating risk assessments. The findings of three OECD guideline-type oral toxicity studies of different duration in rats are summarized in this publication; each study evaluated different titanium dioxide (TiO2) particles of varying sizes and surface coatings. Moreover, each study finding demonstrated an absence of any TiO2 -related hazards. To briefly summarize the findings: 1) In a subchronic 90-day study (OECD TG 408), groups of young adult male and female rats were dosed with rutile-type, surface-coated pigment-grade TiO2 test particles (d50 = 145 nm - 21% nanoparticles by particle number criteria) by oral gavage for 90 days. The no-adverse-effect level (NOAEL) for both male and female rats in this study was 1000 mg/kg bw/day, the highest dose tested. The NOAEL was determined based on a lack of TiO2 particle-related adverse effects on any in-life, clinical pathology, or anatomic/microscopic pathology parameters; 2) In a 28-day repeated-dose oral toxicity study (OECD TG 407), groups of young adult male rats were administered daily doses of two rutile-type, uncoated, pigment-grade TiO2 test particles (d50 = 173 nm by number) by daily oral gavage at a dose of 24,000 mg/kg bw/day. There were no adverse effects measured during or following the end of the exposure period; and the NOAEL was determined to be 24,000 mg/kg bw/day; 3) In an acute oral toxicity study (OECD TG 425), female rats were administered a single oral exposure of surface-treated rutile/anatase nanoscale TiO2 particles (d50 = 73 nm by number) with doses up to 5000 mg/kg and evaluated over a 14-day post-exposure period. Under the conditions of this study, the oral LD50 for the test substance was >5000 mg/kg bw. In summary, the results from these three toxicity studies - each with different TiO2 particulate-types, demonstrated an absence of adverse toxicological effects. Apart from reporting the findings of these three studies, this publication also focuses on additional critical issues associated with particle and nanotoxicology studies. First, describing the detailed methodology requirements and rigor upon which the standardized OECD 408 guideline subchronic oral toxicity studies are conducted. Moreover, an attempt is made to reconcile the complex issue of particle size distribution as it relates to measurements of nanoscale and pigment-grade TiO2 particles. Clearly this has been a confusing issue and often misrepresented in the media and the scientific literature. It is clear that the particle-size distribution for pigment-grade TiO2, contains a small ("tail") component of nanoscale particles (i.e., 21% by particle number and <1% by weight in the test material used in the 90-day study). However, this robust particle characterization finding should not be confused with mislabeling the test materials as exclusively in the nanoscale range. Moreover, based upon the findings presented herein, there appears to be no significant oral toxicity impact contributed by the nanoscale component of the TiO2 Test Material sample in the 90-day study. Finally, it seems reasonable to conclude that the study findings should be considered for read-across purposes to food-grade TiO2 particles (e.g., E171), as the physicochemical characteristics are quite similar.

First Melody(®) valve implantations in Africa.

Congenital heart lesions involving the right ventricular outflow tract (RVOT) are a common problem in paediatric cardiology. These patients need multiple surgical interventions in the form of valved conduits over a lifetime. Surgical re-valvulation was the standard treatment option until the introduction of percutaneous pulmonary valves over a decade ago. These valves can be used to prolong the lifespan of conduits and reduce the number of re-operations. The Melody(®) valve (Medtronic, Minneapolis, MN, USA) was introduced as the first dedicated percutaneous pulmonary valve. Percutaneous pulmonary valves can be implanted successfully and have the advantage of short hospitalisations. We describe the first three Melody(®) valve implantations in Africa.

Complete high-intensity focused ultrasound in prostate cancer: outcome from the @-Registry.

BACKGROUND: To analyze data on patients with localized prostate cancer who were treated with complete high-intensity focused ultrasound (HIFU) prospectively captured within a voluntary HIFU user database (@-Registry). METHODS: The @-Registry includes data from consecutive patients treated with Ablatherm (EDAP-TMS) HIFU at nine European Centres during the period 1994 and 2009. For this analysis, the data repository was reviewed for information on patients with localized prostate cancer (T1 -- T2) treated with complete (whole-gland) HIFU on the basis of an anterior-posterior prostate height of ≤24 mm and a treated volume >120% of the prostate volume. Patients were regularly followed with PSA measurement and biopsy. Biochemical failure was defined for this study as PSA nadir +2 ngml(-1) (Phoenix definition). Disease-free survival was based on a biopsy, retreatment and biochemical data. Patients were risk group-stratified using the D'Amico classification system. RESULTS: The median follow-up was 2.8 years for the 356 patients included in the analysis. The majority could be classified as either low (44.9%) or intermediate risk (39.6%); 14.6% patients were classified as high risk. The median (mean, s.d.) PSA nadir was 0.11 ng ml(-1) (0.78 and 3.6), achieved at a mean (s.d.) of 14.4 (11.6) weeks after HIFU. Follow-up biopsies on 226/356 (63.5%) patients revealed an overall negative biopsy rate of 80.5% (182/226); there was no statistically significant difference in positive biopsy rate by risk group-stratification. Actuarial freedom from biochemical recurrence at 5 and 7 years according to the Phoenix definition was 85% and 79%, respectively. Disease-free progression rates at 5 and 7 years were 64% and 54%, respectively. CONCLUSIONS: Whole-gland prostate HIFU as primary monotherapy for localized prostate cancer achieves a recurrence-free survival in short-term analysis as assessed by prostate biopsy and serum PSA endpoints in a majority of patients.

Flow cytometry analysis: a quantitative method for collagen VI deficiency screening.

Mutations in COL6A1, COL6A2 and COL6A3 genes result in collagen VI myopathies: Ullrich congenital muscular dystrophy (UCMD), Bethlem myopathy (BM) and intermediate phenotypes. At present, none of the existing diagnostic techniques for evaluating collagen VI expression is quantitative, and the detection of subtle changes in collagen VI expression remains challenging. We investigated flow cytometry analysis as a means of quantitatively measuring collagen VI in primary fibroblasts and compared this method with the standard method of fibroblast collagen VI immunohistochemical analysis. Eight UCMD and five BM molecularly confirmed patients were studied and compared to five controls. Flow cytometry analysis consistently detected a reduction of collagen VI of at least 60% in all UCMD cases. In BM cases the levels of collagen VI were variable but on average 20% less than controls. Flow cytometry analysis provides an alternative method for screening for collagen VI deficiency at the protein level in a quantitative, time and cost-effective manner.

Cardiac abnormalities and facial anthropometric measurements in children from the Free State and Northern Cape provinces of South Africa with chromosome 22q11.2 microdeletion.

INTRODUCTION: Microdeletions of chromosome 22 are common and have a prevalence of at least 1/4 000. Cardiac abnormalities, abnormal facial features and palatal abnormalities are frequently present in these patients. AIM: To describe the cardiac lesions and selected measurable facial features in children from the Free State and Northern Cape presenting at the Cardiology Unit of the Universitas Academic Hospital complex in Bloemfontein. METHODS: This was a prospective study in which patients with abnormal facial characteristics were tested using a fluorescence in situ hybridisation (FISH) probe for the 22q11.2 microdeletion. Forty children tested positive for the microdeletion. All patients underwent an echocardiogram and where possible, facial anthropometric measurements were performed. RESULTS: The median age at diagnosis was 3.6 years (range 0.04 years, i.e. 2 weeks to 16.2 years). Tetralogy with or without pulmonary atresia was diagnosed in 43% (n = 17) of the children and truncus arteriosus in 20% (n = 8). A rightsided aortic arch was present in 43% (n = 17) of the patients. Mid-facial height was slightly longer (median = 1.0; range -0.5 to 3.3) and width narrower (median = -1.4; range -2.2 to 0.1) than normal. Ear height and width were notably small compared to normal, with median -scores = -3.3 (range -4.8 to -2.6) and = -2.4 (range -3.4 to -1.4), respectively. CONCLUSIONS: Microdeletions of chromosome 22q11 are present in children from the Free State and Northern Cape. Conotruncal cyanotic heart lesions, especially tetralogy with or without pulmonary atresia and truncus arteriosus were the most frequent congenital cardiac diagnoses. A right-sided aortic arch was also commonly present in these children. Facial features varied and small ears were the most noteworthy anthropometric feature. A right-sided aortic arch with or without a congenital cardiac lesion, a long, narrow mid-face and small ears should alert the physician to the possibility of a microdeletion on the long arm of chromosome 22.

Immunohistological intensity measurements as a tool to assess sarcolemma-associated protein expression.

AIMS: The quantification of protein levels in muscle biopsies is of particular relevance in the diagnostic process of neuromuscular diseases, but is difficult to assess in cases of partial protein deficiency, particularly when information on protein localization is required. The combination of immunohistochemistry and Western blotting is often used in these cases, but is not always possible if the sample is scarce. We therefore sought to develop a method to quantify relative levels of sarcolemma-associated proteins using digitally captured images of immunolabelled sections of skeletal muscle. METHODS: To validate our relative quantification method, we labelled dystrophin and other sarcolemmal proteins in transverse sections of muscle biopsies taken from Duchenne muscular dystrophy and Becker muscular dystrophy patients, a manifesting carrier of Duchenne muscular dystrophy and normal controls. RESULTS: Using this method to quantify relative sarcolemmal protein abundance, we were able to accurately distinguish between the different patients on the basis of the relative amount of dystrophin present. CONCLUSIONS: This comparative method adds value to techniques that are already part of the diagnostic process and can be used with minimal variation of the standardized protocols, without using extra amounts of valuable biopsy samples. Comparative quantification of sarcolemmal proteins on immunostained muscle sections will be of use to establish both the abundance and localization of the protein. Moreover, it can be applied to assess the efficacy of experimental therapies where only partial restoration or upregulation of the protein may occur.