Effects of street tree configuration and placement on roadside thermal environment within a tropical urban canyon.

The Urban Heat Island (UHI) effect increases surface and air temperatures, affecting urban health and well-being. A well-known UHI mitigation measure is the increased roadside tree vegetation facilitating evapotranspiration and shade. In its implementation, the identification of thermally optimal street tree configurations and a quantitative assessment of how various street tree configurations impact the roadside thermal environment were deemed essential and were chosen as the main aims of the study. Twelve tropical urban canyons were categorized into three clusters representative of different street tree placement and configuration scenarios. A control cluster devoid of any roadside trees was also selected. The CFD-based 3-D microclimate model 'ENVI-met' was used to identify suitable roadside urban tree planting scenarios for better microclimate regulation. From a tree planting scenario analysis done as part of the study, the greening scenario of using a 'Continuous tree row (Densely foliated - high Leaf Area Density - LAD)' tree configuration was recognized with the highest ambient temperature reduction of 1.41 °C. The study outcomes reveal that tree configuration of high LAD street trees placed in closer spacing contributes towards the better cooling effect of roadside environments and thus improves thermal comfort for warmer tropical climates of higher humidity levels. The study's findings offer valuable insights for urban planning professionals and policymakers involved in designing future cities and urban developments. They emphasize the importance of strategic tree-planting designs and configurations to enhance thermal comfort and livability in urban areas. This highlights the need to avoid ad-hoc procedures and instead prioritize well-planned roadside tree configurations within urban canyons.

Establishment of a cell line for assessing drugs as canine P-glycoprotein substrates: proof of principle.

P-glycoprotein (P-gp), encoded by the ABCB1 (MDR1) gene, dramatically impacts drug disposition. P-gp is expressed in the intestines, biliary canaliculi, renal tubules, and brain capillaries where it functions to efflux substrate drugs. In this capacity, P-gp restricts oral absorption, enhances biliary and renal excretion, and inhibits central nervous system entry of substrate drugs. Many drugs commonly used in veterinary medicine are known substrates for canine P-gp (vincristine, loperamide, ivermectin, others). Because these drugs have a narrow therapeutic index, defective P-gp function can cause serious adverse drug reactions due to enhanced brain penetration and/or decreased clearance. P-gp dysfunction in dogs can be intrinsic (dogs harboring ABCB1-1Δ) or acquired (drug interactions between a P-gp inhibitor and P-gp substrate). New human drug candidates are required to undergo assessment for P-gp interactions according to FDA and EMA regulations to avoid adverse drug reactions and drug-drug interactions. Similar information regarding canine P-gp could prevent adverse drug reactions in dogs. Because differences in P-gp substrates have been documented between species, one should not presume that human or murine P-gp substrates are necessarily canine P-gp substrates. Thus, our goal was to develop a cell line for assessing drugs as canine P-gp substrates.

Effects of paraplegia on quality of life and family economy among patients with spinal cord injuries in selected hospitals of Sri Lanka.

OBJECTIVES: The study was conducted with the aim of assessing the effects of paraplegia caused by spinal cord injuries on the quality of life of patients and their family economy. STUDY DESIGN: A descriptive cross-sectional study. SETTING: The study was carried out in Accident Service, Orthopedic and Neurosurgery Units of the National Hospital of Sri Lanka and the Spinal Injury Unit of Rehabilitation Hospital Ragama. METHODS: One hundred traumatic paraplegic patients were included as the study sample. Modified Ferrans and Powers quality of life index: spinal cord injury version was used to measure the quality of life. Pre- and post-family economic data were collected using an interviewer-administered questionnaire. RESULTS: Quality of Life was calculated under four major components. Paraplegics' family component (mean=3.50) and social, economic aspects (mean=3.24) are considerably good when compared with health and functioning (mean=2.83) and psychological (mean=2.78) components. Also the study revealed that expenditures are significantly high (P=0.001) and income is significantly less (P=0.001) after injury than before. CONCLUSION: Quality of life is relatively good on family and social aspects, whereas the physical and psychological aspects are somewhat poor. Regarding family economy, expenses are significantly high and earnings are significantly less after the injury. Contribution to the income from self-employment shows the most significant decline. Findings suggest that the family economy of such patients should be supported.

Relationship between increased risk of falling and cognitive impairment in residents of an elderly home in the Colombo district.

Tendency to falling in older people, with and without cognitive impairment, living in an elderly home was assessed. A descriptive analytical study was carried out with 50 elderly people (25 males) aged between 60 - 85 years. Timed Up and Go (TUG) test and, Five Times Sit to Stand Test (FTSST) were used to determine risk of falling and functional lower extremity strength of each participant. The Folstein Mini Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) were used to assess cognition.The cognitive scores were significantly lower in fallers compared to non-fallers (p=0.0001). Fallers demonstrated significantly poor lower extremity strength (p=0.0001). Older people with cognitive impairment demonstrated poor functional lower extremity strength than those without cognitive impairement (p=0.002). The difference in falling tendency between males and females was not statistically significant.

Computational analysis and experimental verification of donor-acceptor behaviour of berberine, and its co-oligomers and co-polymers with ethylenedioxythiophene.

The donor-acceptor (D-A) type of conjugated polymers has emerged as the paradigm of the third generation of electronically conducting polymers demonstrating improved infrared activity and intrinsic electronic conductivity. Judicious selection of donor (D) and acceptor (A) monomers for copolymerization can further fine-tune these properties. Notably, for such refinement, natural compounds provide many conjugated molecules with various functional groups. Berberine cation (Ber+) found in Coscinium fenestratum has extensive conjugation and contains both an electron deficient isoquinolium A moiety and electron-rich D-type methylenedioxy and methoxy groups. The incorporation of natural products in electronic materials is a novel area of research which opens a wide scope for future electronic and optoelectronic devices. Investigation of their fundamental properties via computer simulations is therefore important. In this study, quantum chemical calculations are performed using density functional theory (DFT) to investigate the electronic and optical properties of oligomers of Ber+ and 3,4-ethylenedioxythiophene (EDOT) and to explore the possibilities for homo-polymerization of Ber+ and its copolymerization with EDOT. It has been revealed that homo-polymerization is not favoured but copolymerization with EDOT is possible. As such, Ber+ was copolymerized with EDOT and the copolymers formed by electro-polymerization are extensively characterised and the D-A behaviour of the copolymers verified. Furthermore, the theoretical predictions have been compared with the experimental data.

A case report of giant pancreatic pseudocyst following acute pancreatitis: experience with endoscopic internal drainage.

BACKGROUND: Pancreatic cysts are being diagnosed more frequently because of the increasing usage of imaging techniques. A pseudocyst with the major diameter of 10 cm is termed as a giant cyst. Asymptomatic pseudo-cysts up to 6 cm in diameter can be safely observed and monitored without intervention, but larger and symptomatic pseudocysts require intervention. CASE PRESENTATION: A 27-year-old Sri Lankan male, with history of heavy alcohol use, presented with progressive abdominal distension following an episode of acute pancreatitis. Contrast enhanced CT scan of the abdomen showed a large multilocular cystic lesion almost occupying the entire abdominal cavity and displacing the liver medially and the right dome of the diaphragm superiorly. The largest locule in the right side measured as 30 cm × 15 cm × 14 cm. Endoscopic ultrasound guided drainage of the cyst was performed. The cyst was entered into with an electrocautery-assisted cystotome and a lumen-opposing metal stent was deployed under fluoroscopic vision followed by dilatation with a 10 mm controlled radial expansion balloon. Repeat endoscopic ultrasound was done a week later due to persistence of the collection and a second stent was inserted. Then 10 French gauge × 10 cm double ended pigtails were inserted through both stents. The cysts were not visualized on subsequent Ultra sound scans. Stent removal was done after 3 weeks, leaving the pigtails insitu. The patient made an uneventful recovery. CONCLUSION: Giant pancreatic pseudocysts are rare and earlier drainage is recommended before clinical deterioration. Some experts suggest that cystogastrostomy may not be appropriate for the treatment of giant pancreatic pseudocysts and in some instances external drainage of giant pancreatic pseudocysts may be safer than cystogastrostomy. Video-assisted pancreatic necrosectomy with internal drainage and laparoscopic cystogastrostomy were also tried with a good outcome. With our experience we suggest endoscopic guided internal drainage as a possible initial method of management of a giant pseudo cyst. However long-term follow up is needed with repeated imaging and endoscopy. In instances where the primary endoscopic internal drainage fails, surgical procedures may be required as a second line option.

Comparison of chemotherapeutic drug resistance in cells transfected with canine ABCG2 or feline ABCG2.

ABCG2 (ATP binding cassette subfamily G, member 2) mediates resistance to a variety of cytotoxic agents. Although human ABCG2 is well characterized, the function of canine ABCG2 has not been studied previously. Feline ABCG2 has an amino acid substitution in the adenosine triphosphate-binding domain that decreases its transport capacity relative to human ABCG2. Our goal was to compare canine ABCG2-mediated chemotherapeutic drug resistance to feline ABCG2-mediated chemotherapeutic drug resistance. HEK-293 cells stably transfected with plasmid containing canine ABCG2, feline ABCG2 or no ABCG2 were exposed to carboplatin, doxorubicin, mitoxantrone, toceranib or vincristine, and cell survival was subsequently determined. Canine ABCG2 conferred a greater degree of chemotherapy resistance than feline ABCG2 for mitoxantrone. Neither canine nor feline ABCG2 conferred resistance to doxorubicin, vincristine or toceranib. Canine, but not feline, ABCG2 conferred resistance to carboplatin, a drug that is not reported to be a substrate for ABCG2 in other species.

Submucosal lipoma of the sigmoid colon as a rare cause of mucoid diarrhea: a case report.

BACKGROUND: Symptomatic presentations of colonic lipomas are very rare in clinical practice, and may mimic colonic malignancy. The likelihood of presenting symptoms has been shown to depend on the size of the lesion. CASE PRESENTATION: We describe the case of a 72-year-old Sinhalese man presenting with worsening mucoid diarrhea who was subsequently diagnosed to have a lipoma of the sigmoid colon. His disease was successfully managed with endoscopic resection. CONCLUSION: Confidently establishing the rare diagnosis of a colonic lipoma usually requires a combination of endoscopic, radiological, and histological evaluation, and is therefore very challenging. With the advancement of endoscopic procedures, endoscopic resection is widely practiced as the definitive management of these cases.