208 research outputs found
A saturated genetic linkage map of autotetraploid alfalfa (Medicago sativa L.) developed using genotyping-by-sequencing is highly syntenous with the Medicago truncatula genome.
A genetic linkage map is a valuable tool for quantitative trait locus mapping, map-based gene cloning, comparative mapping, and whole-genome assembly. Alfalfa, one of the most important forage crops in the world, is autotetraploid, allogamous, and highly heterozygous, characteristics that have impeded the construction of a high-density linkage map using traditional genetic marker systems. Using genotyping-by-sequencing (GBS), we constructed low-cost, reasonably high-density linkage maps for both maternal and paternal parental genomes of an autotetraploid alfalfa F1 population. The resulting maps contain 3591 single-nucleotide polymorphism markers on 64 linkage groups across both parents, with an average density of one marker per 1.5 and 1.0 cM for the maternal and paternal haplotype maps, respectively. Chromosome assignments were made based on homology of markers to the M. truncatula genome. Four linkage groups representing the four haplotypes of each alfalfa chromosome were assigned to each of the eight Medicago chromosomes in both the maternal and paternal parents. The alfalfa linkage groups were highly syntenous with M. truncatula, and clearly identified the known translocation between Chromosomes 4 and 8. In addition, a small inversion on Chromosome 1 was identified between M. truncatula and M. sativa. GBS enabled us to develop a saturated linkage map for alfalfa that greatly improved genome coverage relative to previous maps and that will facilitate investigation of genome structure. GBS could be used in breeding populations to accelerate molecular breeding in alfalfa
Reducing one million child deaths from birth asphyxia – a survey of health systems gaps and priorities
BACKGROUND: Millions of child deaths and stillbirths are attributable to birth asphyxia, yet limited information is available to guide policy and practice, particularly at the community level. We surveyed selected policymakers, programme implementers and researchers to compile insights on policies, programmes, and research to reduce asphyxia-related deaths. METHOD: A questionnaire was developed and pretested based on an extensive literature review, then sent by email (or airmail or fax, when necessary) to 453 policymakers, programme implementers, and researchers active in child health, particularly at the community level. The survey was available in French and English and employed 5-point scales for respondents to rate effectiveness and feasibility of interventions and indicators. Open-ended questions permitted respondents to furnish additional details based on their experience. Significance testing was carried out using chi-square, F-test and Fisher's exact probability tests as appropriate. RESULTS: 173 individuals from 32 countries responded (44%). National newborn survival policies were reported to exist in 20 of 27 (74%) developing countries represented, but respondents' answers were occasionally contradictory and revealed uncertainty about policy content, which may hinder policy implementation. Respondents emphasized confusing terminology and a lack of valid measurement indicators at community level as barriers to obtaining accurate data for decision making. Regarding interventions, birth preparedness and essential newborn care were considered both effective and feasible, while resuscitation at community level was considered less feasible. Respondents emphasized health systems strengthening for both supply and demand factors as programme priorities, particularly ensuring wide availability of skilled birth attendants, promotion of birth preparedness, and promotion of essential newborn care. Research priorities included operationalising birth preparedness, effectively evaluating pregnancy risk in the community, ensuring roles for traditional birth attendants (TBAs) that link them with the health system, testing the cost-effectiveness of various community cadres for resuscitation, and developing a clear case definition for case management and population monitoring. CONCLUSION: Without more attention to improve care and advance birth asphyxia research, the 2 million deaths related to asphyxia, plus associated maternal deaths, will remain out of reach of effective care, either skilled or community level, for many years to come
Liposome: a carrier for effective drug delivery
Liposomes are the spherical vesicles containing one or more phospholipid bilayer, which was first described in the middle of 60s by Bangham. The bilayer vesicles are considered as an efficient carrier for drug delivery, diagnostic agents, and also an effective tool for vaccine delivery. Liposome has been used as a potential carrier for several diseases from cardiovascular disease to bacterial infection and also it has the ability to reducing the toxicity of highly potent drugs and simultaneously utilized to improve pharmacokinetics and therapeutic efficacy. A liposome is a formulation which has the capacity to overcome with the limitation of conventional therapies. For the delivery of liposome ocular and inhalation route are some advanced technology. In poorly water soluble substance pulmonary delivery is very much useful. However liposome based vaccines have been demonstrated in clinical trials and further progress in human trails. This review discusses the mechanism of action, Method of preparation, evaluation, application of liposomal drug delivery system along with the recent developments some of the commercially available products
Post-glacial evolution of \u3ci\u3ePanicum virgatum\u3c/i\u3e: centers of diversity and gene pools revealed by SSR markers and cpDNA sequences
Switchgrass (Panicum virgatum), a central and Eastern USA native, is highly valued as a component in tallgrass prairie and savanna restoration and conservation projects and a potential bioenergy feedstock. The purpose of this study was to identify regional diversity, gene pools, and centers-of-diversity of switchgrass to gain an understanding of its post-glacial evolution and to identify both the geographic range and potential overlap between functional gene pools. We sampled a total of 384 genotypes from 49 accessions that included the three main taxonomic groups of switchgrass (lowland 4x, upland 4x, and upland 8x) along with one accession possessing an intermediate phenotype. We identified primary centers of diversity for switchgrass in the eastern and western Gulf Coast regions. Migration, drift, and selection have led to adaptive radiation in switchgrass, creating regional gene pools within each of the main taxa. We estimate that both upland-lowland divergence and 4x-to-8x polyploidization within switchgrass began approximately 1.5–1 M ybp and that subsequent ice age cycles have resulted in gene flow between ecotype lineages and between ploidy levels. Gene flow has resulted in ‘‘hot spots’’ of genetic diversity in the southeastern USA and along the Atlantic Seaboard
ASPEK BIOLOGI CUMI-CUMI (Loligo sp.) YANG TERTANGKAP OLEH NELAYAN DI PERAIRAN MANOKWARI
Squid (Loligo sp.) is one of the fisheries commodities caught in Manokwari waters. The aim of this study was to determine the biological aspects of Loligo sp. including the sex ratio, size distribution, growth pattern, and the lengthy relationship of Loligo sp. from Manokwari waters. This research was conducted in January until March 2017, in three landing sites of squid (Loligo sp) namely Fanindi Pantai, Borobudur and Arowi village. The method used is observation technique in the laboratory includes measurements of length and weight to find out the size distribution and growth pattern of captured Loligo sp. and surgery to determine the sex ratio. The male-female sex ratio of Loligo sp. was 1.3: 1.0 with a range of coat length and wight dominated by male. The growth pattern of Loligo sp in Manokwari waters is negative allometric, where the length increase is faster than the weight gain.Cumi-cumi (Loligo sp.) adalah salah satu komoditi perikanan yang banyak tertangkap oleh nelayan di perairan Manokwari. Penelitian ini bertujuan untuk mengetahui aspek biologi Loligo sp. meliputi rasio kelamin, sebaran ukuran, pola pertumbuhan, dan hubungan panjang-bobot Loligo sp yang tertangkap dengan alat tangkap pancing oleh nelayan asal Manokwari. Penelitian dilakukan pada bulan Januari sampai bulan Maret 2017, di tiga lokasi pendaratan cumi-cumi (Loligo sp) yang berada di Kabupaten Manokwari yakni : Kampung Fanindi Pantai, Borobudur, dan Arowi. Metode yang digunakan yaitu teknik observasi analisis lanjutan di laboratorium meliputi pengukuran panjang dan bobot untuk mengetahui sebaran ukuran dan pola pertumbuhan Loligo sp yang tertangkap serta pembedahan untuk menentukan rasio kelamin. Hasil penelitian menunjukkan bahwa perbandingan jenis kelamin jantan-betina Loligo sp adalah 1,3 : 1,0 dengan didominasi oleh individu jantan di hampir semua selang kelas panjang mantel maupun bobot tubuh. Pola pertumbuhan Loligo sp di perairan Manokwari bersifat allometrik negatif, dimana pertambahan panjang lebih cepat dibanding pertambahan bobot
Absence of cerebrospinal fluid pleocytosis in tuberculous meningitis is a common occurrence in HIV co-infection and a predictor of poor outcomes.
Diagnostic accuracy of Xpert MTB/RIF Ultra for tuberculous meningitis in HIV-infected adults: a prospective cohort study.
BACKGROUND: WHO recommends Xpert MTB/RIF as initial diagnostic testing for tuberculous meningitis. However, diagnosis remains difficult, with Xpert sensitivity of about 50-70% and culture sensitivity of about 60%. We evaluated the diagnostic performance of the new Xpert MTB/RIF Ultra (Xpert Ultra) for tuberculous meningitis. METHODS: We prospectively obtained diagnostic cerebrospinal fluid (CSF) specimens during screening for a trial on the treatment of HIV-associated cryptococcal meningitis in Mbarara, Uganda. HIV-infected adults with suspected meningitis (eg, headache, nuchal rigidity, altered mental status) were screened consecutively at Mbarara Regional Referral Hospital. We centrifuged CSF, resuspended the pellet in 2 mL of CSF, and tested 0·5 mL with mycobacteria growth indicator tube culture, 1 mL with Xpert, and cryopreserved 0·5 mL, later tested with Xpert Ultra. We assessed diagnostic performance against uniform clinical case definition or a composite reference standard of any positive CSF tuberculous test. FINDINGS: From Feb 27, 2015, to Nov 7, 2016, we prospectively evaluated 129 HIV-infected adults with suspected meningitis for tuberculosis. 23 participants were classified as probable or definite tuberculous meningitis by uniform case definition, excluding Xpert Ultra results. Xpert Ultra sensitivity was 70% (95% CI 47-87; 16 of 23 cases) for probable or definite tuberculous meningitis compared with 43% (23-66; 10/23) for Xpert and 43% (23-66; 10/23) for culture. With composite standard, we detected tuberculous meningitis in 22 (17%) of 129 participants. Xpert Ultra had 95% sensitivity (95% CI 77-99; 21 of 22 cases) for tuberculous meningitis, which was higher than either Xpert (45% [24-68]; 10/22; p=0·0010) or culture (45% [24-68]; 10/22; p=0·0034). Of 21 participants positive by Xpert Ultra, 13 were positive by culture, Xpert, or both, and eight were only positive by Xpert Ultra. Of those eight, three were categorised as probable tuberculous meningitis, three as possible tuberculous meningitis, and two as not tuberculous meningitis. Testing 6 mL or more of CSF was associated with more frequent detection of tuberculosis than with less than 6 mL (26% vs 7%; p=0·014). INTERPRETATION: Xpert Ultra detected significantly more tuberculous meningitis than did either Xpert or culture. WHO now recommends the use of Xpert Ultra as the initial diagnostic test for suspected tuberculous meningitis. FUNDING: National Institute of Neurologic Diseases and Stroke, Fogarty International Center, National Institute of Allergy and Infectious Disease, UK Medical Research Council/DfID/Wellcome Trust Global Health Trials, Doris Duke Charitable Foundation
Perception of Ticks and Tick-Borne Diseases Worldwide
In this comprehensive review study, we addressed the challenge posed by ticks and tick-borne diseases (TBDs) with growing incidence affecting human and animal health worldwide. Data and perspectives were collected from different countries and regions worldwide, including America, Europe, Africa, Asia, and Oceania. The results updated the current situation with ticks and TBD and how it is perceived by society with information bias and gaps. The study reinforces the importance of multidisciplinary and international collaborations to advance in the surveillance, communication and proposed future directions to address these challenges
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