Rooftop water harvesting for managed aquifer recharge and flood mitigation in tropical cities: Towards a strategy of co-benefit evaluations in João Pessoa, northeast Brazil.

Intense urbanisation in many coastal areas has led to intensification of groundwater consumption, while reducing permeable areas and increasing the frequency and magnitude of flooding. Among the potential strategies to compensate for these adverse effects, which are expected to become worse as a result of climate change, rooftop rainwater harvesting (RWH) in combination with managed aquifer recharge (MAR), may be indicated. This work investigated the performance of different configurations of such a system, tested as a twofold sustainable stormwater and domestic water management tool in a tropical metropole (João Pessoa, Brazil). This area located over a sedimentary aquifer system illustrates the water security challenges of densely urbanised areas in southern cities. To that end, several configurations of rooftop catchments and storage volumes were evaluated, by simulating a MAR-RWH system connected to the regional unconfined aquifer (Barreiras Formation) through a 6″ diameter injection well. Rainfall-runoff-recharge processes and water balances were simulated using monitored high-temporal resolution rainfall data. The results showed that catchments ranging from 180 to 810 m2, connected to tanks from 0.5 to 30.0 m³, are the optimal solutions in terms of efficient rainwater retention and peak flow reduction. These solutions provided mean annual estimates of aquifer recharge between 57 and 255 m³/yr from 2004 to 2019. The results of this study highlight the opportunity for MAR schemes to reconcile stormwater management and water supply goals.

Cardiac and Metabolic Variables in Obese Dogs.

BACKGROUND: The etiology of obesity-related cardiac dysfunction (ORCD) is linked to metabolic syndrome in people. Studies have indicated that obese dogs have components of metabolic syndrome, warranting evaluation for ORCD in obese dogs. OBJECTIVES: To evaluate cardiac structure and function and metabolic variables in obese dogs compared to ideal weight dogs. ANIMALS: Forty-six healthy, small-breed (<25 pounds), obese dogs (n = 29) compared to ideal weight dogs (n = 17). METHODS: A cross-sectional study of cardiac structure and function by standard and strain echocardiographic measurements and quantification of serum metabolic variables (insulin:glucose ratios, lipid analysis, adiponectin, inflammatory markers). RESULTS: Compared to the ideal weight controls, obese dogs had cardiac changes characterized by an increased interventricular septal width in diastole to left ventricular internal dimension in diastole ratio, decreased ratios of peak early to peak late left ventricular inflow velocities, and ratios of peak early to peak late mitral annular tissue velocities, and increased fractional shortening and ejection fraction percentages. The left ventricular posterior wall width in diastole to left ventricular internal dimension in diastole ratios were not significantly different between groups. Systolic blood pressure was not significantly different between groups. Obese dogs had metabolic derangements characterized by increased insulin:glucose ratios, dyslipidemias with increased cholesterol, triglyceride, and high-density lipoprotein concentrations, decreased adiponectin concentrations, and increased concentrations of interleukin 8 and keratinocyte-derived chemokine-like inflammatory cytokines. CONCLUSIONS AND CLINICAL IMPORTANCE: Compared to ideal weight controls, obese dogs have alterations in cardiac structure and function as well as insulin resistance, dyslipidemia, hypoadiponectinemia, and increased concentrations of inflammatory markers. These findings warrant additional studies to investigate inflammation, dyslipidemia, and possibly systemic hypertension as potential contributing factors for altered cardiac function.

Life in the fat lane: seasonal regulation of insulin sensitivity, food intake, and adipose biology in brown bears.

Grizzly bears (Ursus arctos horribilis) have evolved remarkable metabolic adaptations including enormous fat accumulation during the active season followed by fasting during hibernation. However, these fluctuations in body mass do not cause the same harmful effects associated with obesity in humans. To better understand these seasonal transitions, we performed insulin and glucose tolerance tests in captive grizzly bears, characterized the annual profiles of circulating adipokines, and tested the anorectic effects of centrally administered leptin at different times of the year. We also used bear gluteal adipocyte cultures to test insulin and beta-adrenergic sensitivity in vitro. Bears were insulin resistant during hibernation but were sensitive during the spring and fall active periods. Hibernating bears remained euglycemic, possibly due to hyperinsulinemia and hyperglucagonemia. Adipokine concentrations were relatively low throughout the active season but peaked in mid-October prior to hibernation when fat content was greatest. Serum glycerol was highest during hibernation, indicating ongoing lipolysis. Centrally administered leptin reduced food intake in October, but not in August, revealing seasonal variation in the brain's sensitivity to its anorectic effects. This was supported by strong phosphorylated signal transducer and activator of transcription 3 labeling within the hypothalamus of hibernating bears; labeling virtually disappeared in active bears. Adipocytes collected during hibernation were insulin resistant when cultured with hibernation serum but became sensitive when cultured with active season serum. Heat treatment of active serum blocked much of this action. Clarifying the cellular mechanisms responsible for the physiology of hibernating bears may inform new treatments for metabolic disorders.

A protocol for the isolation and cultivation of brown bear (Ursus arctos) adipocytes.

Brown bears (Ursus arctos) exhibit hyperphagia each fall and can become obese in preparation for hibernation. They do this without displaying the physiological problems typically seen in obese humans, such as Type 2 diabetes and heart disease. The study of brown bear hibernation biology could therefore aid in the development of novel methods for combating metabolic diseases. To this end, we isolated mesenchymal stem cells from subcutaneous fat biopsies, and culture methods were developed to differentiate these into the adipogenic lineage. Biopsies were taken from 8 captive male (N = 6) and female (N = 2) brown bears, ages 2-12 years. Plastic adherent, fibroblast-like cells were proliferated and subsequently cryopreserved or differentiated. Differentiation conditions were optimized with respect to fetal bovine serum content and time spent in differentiation medium. Cultures were characterized through immunostaining, RT-qPCR, and Oil red O staining to quantify lipid accumulation. Adiponectin, leptin, and glycerol medium concentrations were also determined over the course of differentiation. The culturing protocol succeeded in generating hormone-sensitive lipase-expressing, lipid-producing white-type adipocytes (UCP1 negative). Serum concentration and time of exposure to differentiation medium were both positively related to lipid production. Cells cultured to low passage numbers retained similar lipid production and expression of lipid markers PLIN2 and FABP4. Ultimately, the protocols described here may be useful to biologists in the field investigating the health of wild bear populations and could potentially increase our understanding of metabolic disorders in humans.

Identification of DNA variants in the canine beta-1 adrenergic receptor gene.

Beta-adrenergic receptor antagonists are utilized for the management of several cardiac diseases in the dog. In humans the beneficial effects of beta-adrenergic receptor antagonists are variable and are associated with a genetic variability in the beta one adrenergic receptor gene (ADRB1). To determine if DNA variants were present in the canine ADRB1 gene, DNA from five breeds of dogs was evaluated. Two deletions were identified within the region of the gene that encodes the cytoplasmic tail of ADRB1. The functions of this region are not well understood although it is important in differentiating subtypes of adrenergic receptors and may be associated with control of receptor downregulation. The functional consequences of these identified variants deserve further study.

Left atrial function in cats with left-sided cardiac disease and pleural effusion or pulmonary edema.

BACKGROUND: Congestive heart failure (CHF) in cats with left-sided heart disease is sometimes manifest as pleural effusion, in other cases as pulmonary edema. HYPOTHESIS: Those cats with pleural effusion have more severe left atrial (LA) dysfunction than cats with pulmonary edema. ANIMALS: 30 healthy cats, 22 cats with pleural effusion, and 12 cats with pulmonary edema. All cats were client owned. METHODS: Retrospective study. Measurements of LA size and function were made using commercial software on archived echocardiograms. Cases were identified through searches of medical records and of archived echocardiograms for cats with these conditions. RESULTS: There was no difference (P = .3) in LA size between cats with pleural effusion and cats with pulmonary edema. Cats with pleural effusion had poorer (P = .04) LA active emptying and increased (P = .006) right ventricular (RV) diameter when compared with cats with pulmonary edema and healthy cats. Cats that exhibited LA active emptying of <7.9%, total emptying of <13.6% (diameter) or <19.4% (area), or RV diameter of >3.6 mm were significantly (P < .001) more likely to manifest pleural effusion. CONCLUSIONS AND CLINICAL IMPORTANCE: Poorer LA function and increased RV dimensions are associated with pleural effusion in cats with left-sided heart disease.

Familial subvalvular aortic stenosis in golden retrievers: inheritance and echocardiographic findings.

OBJECTIVES: To describe the echocardiographic findings and pedigree analysis of golden retrievers with subvalvular aortic stenosis. METHODS: Seventy-three golden retrievers were evaluated by auscultation and echocardiography. A subcostal continuous-wave Doppler aortic velocity ê2·5 m/s and presence of a left basilar systolic ejection murmur were required for diagnosis of subvalvular aortic stenosis. Three echocardiographic characteristics were recorded: evidence of aortic insufficiency, subvalvular ridge or left ventricular hypertrophy. A disease status score was calculated by totalling the number of echocardiographic -characteristics per subject. RESULTS: Thirty-two of 73 dogs were affected and their aortic velocities were as follows: range 2·5 to 6·8 m/s, median 3·4 m/s and standard deviation 1·2 m/s. Echocardiographic characteristics of 32 affected dogs were distributed as follows: left ventricular hypertrophy 12 of 32, aortic insufficiency 20 of 32 and subvalvular ridge 20 of 32. Disease status score ranged from 0 to 3 with a median of 2. There was a statistically significant correlation between aortic velocity and disease status score (r=0·644, P<0·0001). Subvalvular aortic stenosis was observed in multiple generations of several families and appears familial. CLINICAL SIGNIFICANCE: Subvalvular aortic stenosis in the golden retriever is familial. Severity of stenosis correlates well with cumulative presence of echocardiographic characteristics (left ventricular hypertrophy, subvalvular ridge and aortic insufficiency).

Identification of beta-1 adrenergic receptor polymorphisms in cats.

In human beings, genetic polymorphisms within the beta-1 adrenergic receptor (ADRB1) gene have been associated with variable pharmacologic responses to beta blocker therapy. Beta-blockers are commonly given to cats with heart disease, particularly hypertrophic cardiomyopathy, a common cause of feline heart disease. We hypothesized that polymorphisms are present in the feline ADRB1 gene, which could result in an altered pharmacologic response to beta-blocker therapy. We sequenced the feline ADRB1 gene in 42 cats of five breeds. We identified three polymorphisms within the ADRB1 gene. Two polymorphisms did not change the amino acid produced and are unlikely to be clinically significant. A third polymorphism identified was an AA/CC substitution at the 830-831 base pair sites. This alteration changed the amino acid produced from proline to glutamine at position 277 and computer modeling predicts an altered protein structure. Further study is warranted to determine if this polymorphism alters response to beta blocker therapy.

Increased cardiac alpha-myosin heavy chain in left atria and decreased myocardial insulin-like growth factor (Igf-I) expression accompany low heart rate in hibernating grizzly bears.

Grizzly bears (Ursus arctos horribilis) tolerate extended periods of extremely low heart rate during hibernation without developing congestive heart failure or cardiac chamber dilation. Left ventricular atrophy and decreased left ventricular compliance have been reported in this species during hibernation. We evaluated the myocardial response to significantly reduced heart rate during hibernation by measuring relative myosin heavy-chain (MyHC) isoform expression and expression of a set of genes important to muscle plasticity and mass regulation in the left atria and left ventricles of active and hibernating bears. We supplemented these data with measurements of systolic and diastolic function via echocardiography in unanesthetized grizzly bears. Atrial strain imaging revealed decreased atrial contractility, decreased expansion/reservoir function (increased atrial stiffness), and decreased passive-filling function (increased ventricular stiffness) in hibernating bears. Relative MyHC-α protein expression increased significantly in the atrium during hibernation. The left ventricle expressed 100% MyHC-ß protein in both groups. Insulin-like growth factor (IGF-I) mRNA expression was reduced by ∼50% in both chambers during hibernation, consistent with the ventricular atrophy observed in these bears. Interestingly, mRNA expression of the atrophy-related ubiquitin ligases Muscle Atrophy F-box (MAFBx) and Muscle Ring Finger 1 did not increase, nor did expression of myostatin or hypoxia-inducible factor 1α (HIF-1α). We report atrium-specific decreases of 40% and 50%, respectively, in MAFBx and creatine kinase mRNA expression during hibernation. Decreased creatine kinase expression is consistent with lowered energy requirements and could relate to reduced atrial emptying function during hibernation. Taken together with our hemodynamic assessment, these data suggest a potential downregulation of atrial chamber function during hibernation to prevent fatigue and dilation due to excessive work against an optimally filled ventricle, a response unpredicted by the Frank-Starling mechanism.

Gastric emptying as assessed by barium-impregnated polyethylene spheres in healthy dogs consuming a commercial kibble ration.

Barium-impregnated polyethylene spheres (BIPS) were used to assess gastric emptying in medium-sized dogs consuming a commercial kibble ration. Two sizes of spheres were used: 1.5 mm and 5.0 mm in diameter. Ventrodorsal and right lateral recumbent radiographs were taken immediately before and after consumption of the test meal, and then hourly. The lag phase and the time to 25% (GET25), 50% (GET50), and 75% (GET75) gastric emptying of each sized marker were calculated. There was no significant difference between the lag phases of the small and large BIPS. There was a significant difference between the 1.5 and 5.0 markers at GET25, GET50, and GET75 in these medium-sized dogs. In a majority (70%) of the dogs in this study, GET25 of the 1.5-mm marker occurred at 4.73+/-1.44 hours; GET50 (1.5 mm) occurred at 8.29+/-1.62 hours, and GET75 (1.5 mm) occurred at 10.82+/-1.35 hours. The 5.0-mm markers tended to empty erratically and slowly. Four of the eight dogs retained some of the large markers in their stomachs at the end of the study period (24 hours).

Retrospective evaluation of occlusion of patent ductus arteriosus with hemoclips in 20 dogs.

Twenty dogs with patent ductus arteriosus occluded with Hemoclips were evaluated with a mean follow-up time of 799.4 days (range, 83 to 3,580 days). Significant decreases were found between pre- and postsurgical means for vertebral heart size and for echocardiographic left atrial/aortic-root ratios and percent fractional shortening (%FS). Despite a good clinical outcome, six of 20 dogs had persistent cardiomyopathy of overload with diminished %FS (28% or less) at follow-up. One dog had residual ductal flow identified five days postoperatively. Subsequent evaluations in this case at 60, 144, 226, 344, and 560 days postoperatively demonstrated gradually diminishing ductal flow. The remaining 19 dogs did not recanalize.

ACR-NEMA digital imaging and communications standards: minimum requirements.

The purposes, implications, and history of development of the American College of Radiology-National Electrical Manufacturers Association (ACR-NEMA) Digital Imaging and Communication Standard and its contents are briefly described, and the minimum requirements of the ACR-NEMA Digital Imaging and Communication Standard are described with a concise introduction of each layer. The usefulness, validity, current status, and future development of the standard are also discussed.