40 research outputs found
Pteridopytic diversity in Loolkandura forest
The plant category ferns and fern allies are taxonomically known as Pteridophytes. In Sri Lanka about340 Pteridophytes have been recorded belongs to 29 families. They have ornamental, medicinal andedible values and play an important role in biodiversity of forest understory. Unlike flowering plants,studies on Pteridophytes are Iimited in Sri Lanka. Sri Lanka's first tea plantation has started in Loolkanduraarea but the remaining hilly areas still exists as undisturbed forests with high biodiversity. Howeverlimited studies have been carried out on biodiversity of Loolkandura forest area. Consequently, theobjective of this study was identification ofPteridophytic diversity ofLoolkandura forest area.Three elevation levels (1100, 1300 and 1500 m) were selected along the stream networks and threeplots (each of lOx 10m) from each elevation level were established for sampling. Number of species,their population size and habitats were assessed for each plot. Data were analyzed to identify correlationof species and individuals with elevation levels. A total of 56 Pteridophytes from 19 families wereidentified from studied area. Seventeen percent of Sri Lankan Pteridophytic flora represent in Loolkanduraforest area which consists 3 endemic species (Cyathea walkerae, Meringium macroglossum andDiplazium beddomei). Two main Pteridophytic habitats were identified as lithophytes and terrestrial(terrestrial dense forest, terrestrial open and terrestrial road side). In Loolkandura forest area, bothnumber of families and number of species are in increasing trend with increasing of elevation. Thereare three species namely, {15plenium nomale (R-= 0.69), Metathelypteris flassida (W = 0.54) andPolystichum biaristatum (R -= 0.64) showed significantly positive relationship with number of individualof a specie~ with increasing of elevation from 11,00 to 1500 m. Two species namely Araehniodesaristata (W= 0.69) and Teetaria decurrenee (W= 0.59) showed decreasing trend in number ofindividuals with increasing of elevation. Disturbances to the ecosystem and soil moisture content wereidentified as major parameters to variations of Metathelypteris flassida and Araehniodes aristata.Check Iist for Pteridophytes was prepared for the studied area and impl ications offind ings on conservationand uti Iization of Pteridophytes are discussed.
Pteridophyte flora of Udawattakele forest the past, present and future
Pteridophytes represent an important group in the plant kingdom. Approximately 11,300 Pteridophytespecies have been described worldwide, ofwhich about 360 species have been recorded in Sri Lanka.Most of Sri Lankan Pteridophyte species is concentrated in the understory of the rainforests ofCentral Highlands. Udawattakele forest with 132 ha was one of such highlands (510 m above sealevel) which received special attention by European Pteridologists, even during the colonial era. It hasbeen reported that 13 species are already extinct from Sri Lanka mainly because of various threatsfaced by Pteridophytes. Thus, the objective of this study was to compare the diversity of Pteridophyteflora at present with the previous records and identify possible conservation issues.Species diversity of Pteridophytes at Udawattakele forest in the past was obtained from reviewing ofliterature (Karunarathne, 1986; Sledge, 1950-1981) and observations of preserved specimens at theNational Herbarium. Two line transects (10m x 4000 m) on both side of Lady Horton's Walk wereassessed to identify the present level of Pteridophyte diversity. Almost all Pteridophyte species wereidentified at species level through morphological observations and subsequently with the help of keys.The Lady Horton's Walk was selected for the study, because the majority of Pteridophytes atUdawattakele was concentrated in this area and previous assessments of Pteridophytic diversityhave been conducted in the area. At the selected locations species were counted to identify dominantspecies.According to literature, 25 Ptridophytic species and 4 hybrids (29 taxa) have been collected fromLady Horton '5 Walk in Udawattakele forest. Chronologically 7, 17,2 and 3 taxa have been recordedfrom 1888-1900, 1950-1954, 1973 and 1993, respectively. Out of 29 taxa collected by foreignPteridologists, only preserved specimens of27 taxa have been deposited in the British Museum andthe Kew Herbarium. Karunarathne (1986) recorded 23 Pteridophyte species from the forest. Thepresent study was able to identify 36 Pteridophyte species belong to 9 families and 20 genera from theforest, of which 29 species are common and usually grow on harsh environment in the disturbed areasand roadside banks. Seven species occur in relatively high moist and shaded areas of the forest. Thepresent study was able to record 13 additional species compared to Karaunarathne (1986). However,out of 29 taxa recorded in the literature, 9 species were recorded during the present study. Further, 7species iArthropteris palisotti, Christella hispidula x C. parasitica, Diplazium sylvasticum,Microlepia speluncae, Pronephrium articulatum, Teetaria subtriphylla and T trimenii) had notbeen recorded even in the other parts ofthe country during the last 50 years. The present study wasalso unable to record such species from Udawattakele forest. Out of the above 7 species, two rarespecies namely, Pronephrium artieulatum and Christella hispidula x C. parasitiea had beenrecorded only once over the last century. Such records were also found from Lady Horton's Walk inUdawattakele forest before 50 years.However, at present the Lady Horton's walk has severely been invaded by Myroxylon balsamumsuppressing its native biodiversity. Further, roadside banks of the Lady Horton's walk have very dryconditions. Few wet and shaded areas are also invaded by a naturalized fern species such as Adiantumpulverulent um and it has become dominant species in the area. Such causes may have contributedfor loss of some Pteridophyts species from Udawattakele forest. It is well known that Pteridophytesare very sensitive to changes of environmental conditions and human activities. This raises the issueof necessity of continuous monitoring ofPteridophytic biodiversity for their conservation even withintheir natural habitats.
STATUS OF BIODIVERSITY OF MAHAWELI RIVER AND ITS RIVER BANKS BETWEEN WATAWALA AND GINIGATHHENA
A systematic survey was conducted from January to August 2003 to identify existingmajor habitats, status of biodiversity with respect to flora (flowering plants and fern andfern allies) and fauna (birds and mammals, butterflies, amphibians and freshwater fishspecies), and threats they faced in the Mahaweli river and adjacent river banks betweenWatawala and Nawalapitiya. The flora and fauna were documented using scientificallyvalid techniques.The survey enabled to identify seven major vegetationlhabitats along the Mahaweli riverand its adjacent river banks. They are: river bank habitat with secondary growth; flowingfresh water habitat; ephemeral and perennial small stream water habitat; scrub forestarea; Pinus plantation, homegardens, Albizia dominated abandoned tea plantation, teaplantation, abandoned tea plantation with grassland, and Eucalyptus plantation. Withinthe stretch, a total of 170 species of flowering plants and fern and fern allies belongs to64 families were identified. A total of 18 species of birds (9 families), 16 species ofbutterflies (7 families), 10 species of freshwater fishes (5 families), 16 species of reptiles(7 families), 7 species of amphibians (3 families) and 13 species of mammals (10families) have also been documented.At present, the biodiversity of Mahaweli river and its adjacent river banks hasbeen subjected to several threats, namely pollution due to garbage disposal (mainly atGinigathhena), spread of alien invasive species (mainly at river banks due to Clusiarosea), direct exploitation of species (freshwater fish species), encroachment of bankreservation, unplanned land use practices and small hydropower projects. The criticallyaffected group as a result of these threats is fresh wa•er fish species, which includes 6threatened endemic species. Thus, clear mitigatory measures will be required to avoiddisturbances to such species.
Intranasal Delivery of E-Selectin Reduces Atherosclerosis in ApoE−/− Mice
Mucosal tolerance to E-selectin prevents stroke and protects against ischemic brain damage in experimental models of stroke studying healthy animals or spontaneously hypertensive stroke-prone rats. A reduction in inflammation and neural damage was associated with immunomodulatory or “tolerogenic” responses to E-selectin. The purpose of the current study on ApoE deficient mice is to assess the capacity of this stroke prevention innovation to influence atherosclerosis, a major underlying cause for ischemic strokes; human E-selectin is being translated as a potential clinical prevention strategy for secondary stroke. Female ApoE−/− mice received intranasal delivery of E-selectin prior to (pre-tolerization) or simultaneously with initiation of a high-fat diet. After 7 weeks on the high-fat diet, lipid lesions in the aorta, serum triglycerides, and total cholesterol were assessed as markers of atherosclerosis development. We also assessed E-selectin-specific antibodies and cytokine responses, in addition to inflammatory responses that included macrophage infiltration of the aorta and altered gene expression profiles of aortic mRNA. Intranasal delivery of E-selectin prior to initiation of high-fat chow decreased atherosclerosis, serum total cholesterol, and expression of the leucocyte chemoattractant CCL21 that is typically upregulated in atherosclerotic lesions of ApoE−/− mice. This response was associated with the induction of E-selectin specific cells producing the immunomodulatory cytokine IL-10 and immunosuppressive antibody isotypes. Intranasal administration of E-selectin generates E-selectin specific immune responses that are immunosuppressive in nature and can ameliorate atherosclerosis, a major risk factor for ischemic stroke. These results provide additional preclinical support for the potential of induction of mucosal tolerance to E-selectin to prevent stroke
Bio-Repository of DNA in stroke (BRAINS): A study protocol
<p>Abstract</p> <p>Background</p> <p>Stroke is one of the commonest causes of mortality in the world and anticipated to be an increasing burden to the developing world. Stroke has a genetic basis and identifying those genes may not only help us define the mechanisms that cause stroke but also identify novel therapeutic targets. However, large scale highly phenotyped DNA repositories are required in order for this to be achieved.</p> <p>Methods</p> <p>The proposed Bio-Repository of DNA in Stroke (BRAINS) will recruit all subtypes of stroke as well as controls from two different continents, Europe and Asia. Subjects recruited from the UK will include stroke patients of European ancestry as well as British South Asians. Stroke subjects from South Asia will be recruited from India and Sri Lanka. South Asian cases will also have control subjects recruited.</p> <p>Discussion</p> <p>We describe a study protocol to establish a large and highly characterized stroke biobank in those of European and South Asian descent. With different ethnic populations being recruited, BRAINS has the ability to compare and contrast genetic risk factors between those of differing ancestral descent as well as those who migrate into different environments.</p
Consensus standards for acquisition, measurement, and reporting of intravascular optical coherence tomography studies
Objectives: The purpose of this document is to make the output of the International Working Group for Intravascular Optical Coherence Tomography (IWG-IVOCT) Standardization and Validation available to medical and scientific communities, through a peer-reviewed publication, in the interest of improving the diagnosis and treatment of patients with atherosclerosis, including coronary artery disease. Background: Intravascular optical coherence tomography (IVOCT) is a catheter-based modality that acquires images at a resolution of ∼10 μm, enabling visualization of blood vessel wall microstructure in vivo at an unprecedented level of detail. IVOCT devices are now commercially available worldwide, there is an active user base, and the interest in using this technology is growing. Incorporation of IVOCT in research and daily clinical practice can be facilitated by the development of uniform terminology and consensus-based standards on use of the technology, interpretation of the images, and reporting of IVOCT results. Methods: The IWG-IVOCT, comprising more than 260 academic and industry members from Asia, Europe, and the United States, formed in 2008 and convened on the topic of IVOCT standardization through a series of 9 national and international meetings. Results: Knowledge and recommendations from this group on key areas within the IVOCT field were assembled to generate this consensus document, authored by the Writing Committee, composed of academicians who have participated in meetings and/or writing of the text. Conclusions: This document may be broadly used as a standard reference regarding the current state of the IVOCT imaging modality, intended for researchers and clinicians who use IVOCT and analyze IVOCT data
Global, regional, and national burden of osteoarthritis, 1990–2020 and projections to 2050: a systematic analysis for the Global Burden of Disease Study 2021
Background
Osteoarthritis is the most common form of arthritis in adults, characterised by chronic pain and loss of mobility. Osteoarthritis most frequently occurs after age 40 years and prevalence increases steeply with age. WHO has designated 2021–30 the decade of healthy ageing, which highlights the need to address diseases such as osteoarthritis, which strongly affect functional ability and quality of life. Osteoarthritis can coexist with, and negatively effect, other chronic conditions. Here we estimate the burden of hand, hip, knee, and other sites of osteoarthritis across geographies, age, sex, and time, with forecasts of prevalence to 2050.
Methods
In this systematic analysis for the Global Burden of Disease Study, osteoarthritis prevalence in 204 countries and territories from 1990 to 2020 was estimated using data from population-based surveys from 26 countries for knee osteoarthritis, 23 countries for hip osteoarthritis, 42 countries for hand osteoarthritis, and US insurance claims for all of the osteoarthritis sites, including the other types of osteoarthritis category. The reference case definition was symptomatic, radiographically confirmed osteoarthritis. Studies using alternative definitions from the reference case definition (for example self-reported osteoarthritis) were adjusted to reference using regression models. Osteoarthritis severity distribution was obtained from a pooled meta-analysis of sources using the Western Ontario and McMaster Universities Arthritis Index. Final prevalence estimates were multiplied by disability weights to calculate years lived with disability (YLDs). Prevalence was forecast to 2050 using a mixed-effects model.
Findings
Globally, 595 million (95% uncertainty interval 535–656) people had osteoarthritis in 2020, equal to 7·6% (95% UI 6·8–8·4) of the global population, and an increase of 132·2% (130·3–134·1) in total cases since 1990. Compared with 2020, cases of osteoarthritis are projected to increase 74·9% (59·4–89·9) for knee, 48·6% (35·9–67·1) for hand, 78·6% (57·7–105·3) for hip, and 95·1% (68·1–135·0) for other types of osteoarthritis by 2050. The global age-standardised rate of YLDs for total osteoarthritis was 255·0 YLDs (119·7–557·2) per 100 000 in 2020, a 9·5% (8·6–10·1) increase from 1990 (233·0 YLDs per 100 000, 109·3–510·8). For adults aged 70 years and older, osteoarthritis was the seventh ranked cause of YLDs. Age-standardised prevalence in 2020 was more than 5·5% in all world regions, ranging from 5677·4 (5029·8–6318·1) per 100 000 in southeast Asia to 8632·7 (7852·0–9469·1) per 100 000 in high-income Asia Pacific. Knee was the most common site for osteoarthritis. High BMI contributed to 20·4% (95% UI –1·7 to 36·6) of osteoarthritis. Potentially modifiable risk factors for osteoarthritis such as recreational injury prevention and occupational hazards have not yet been explored in GBD modelling.
Interpretation
Age-standardised YLDs attributable to osteoarthritis are continuing to rise and will lead to substantial increases in case numbers because of population growth and ageing, and because there is no effective cure for osteoarthritis. The demand on health systems for care of patients with osteoarthritis, including joint replacements, which are highly effective for late stage osteoarthritis in hips and knees, will rise in all regions, but might be out of reach and lead to further health inequity for individuals and countries unable to afford them. Much more can and should be done to prevent people getting to that late stage
Global, regional, and national sex-specific burden and control of the HIV epidemic, 1990-2019, for 204 countries and territories: the Global Burden of Diseases Study 2019
Background: The sustainable development goals (SDGs) aim to end HIV/AIDS as a public health threat by 2030. Understanding the current state of the HIV epidemic and its change over time is essential to this effort. This study assesses the current sex-specific HIV burden in 204 countries and territories and measures progress in the control of the epidemic.
Methods: To estimate age-specific and sex-specific trends in 48 of 204 countries, we extended the Estimation and Projection Package Age-Sex Model to also implement the spectrum paediatric model. We used this model in cases where age and sex specific HIV-seroprevalence surveys and antenatal care-clinic sentinel surveillance data were available. For the remaining 156 of 204 locations, we developed a cohort-incidence bias adjustment to derive incidence as a function of cause-of-death data from vital registration systems. The incidence was input to a custom Spectrum model. To assess progress, we measured the percentage change in incident cases and deaths between 2010 and 2019 (threshold >75% decline), the ratio of incident cases to number of people living with HIV (incidence-to-prevalence ratio threshold <0·03), and the ratio of incident cases to deaths (incidence-to-mortality ratio threshold <1·0).
Findings: In 2019, there were 36·8 million (95% uncertainty interval [UI] 35·1–38·9) people living with HIV worldwide. There were 0·84 males (95% UI 0·78–0·91) per female living with HIV in 2019, 0·99 male infections (0·91–1·10) for every female infection, and 1·02 male deaths (0·95–1·10) per female death. Global progress in incident cases and deaths between 2010 and 2019 was driven by sub-Saharan Africa (with a 28·52% decrease in incident cases, 95% UI 19·58–35·43, and a 39·66% decrease in deaths, 36·49–42·36). Elsewhere, the incidence remained stable or increased, whereas deaths generally decreased. In 2019, the global incidence-to-prevalence ratio was 0·05 (95% UI 0·05–0·06) and the global incidence-to-mortality ratio was 1·94 (1·76–2·12). No regions met suggested thresholds for progress. Interpretation: Sub-Saharan Africa had both the highest HIV burden and the greatest progress between 1990 and 2019. The number of incident cases and deaths in males and females approached parity in 2019, although there remained more females with HIV than males with HIV. Globally, the HIV epidemic is far from the UNAIDS benchmarks on progress metrics.
Funding: The Bill & Melinda Gates Foundation, the National Institute of Mental Health of the US National Institutes of Health (NIH), and the National Institute on Aging of the NIH