11 research outputs found
Fluctuations in Serum magnesium and Systemic Arterial Blood Pressures during the Menstrual Cycle in young reproductive women
No full textIntroduction: The menstrual cycle involves a sequence of structural, functional, and hormonal changes in the
reproductive system. This is linked and controlled by cyclical fluctuations in the levels of FSH, LH, estrogen,
and progesterone. Because of these cyclical fluctuations, there might also be associated cyclical changes of
magnesium and systemic arterial blood pressures during the menstrual cycle. Purpose: To assess the changes in
serum magnesium level and systemic arterial blood pressures during the menstrual cycle in young reproductive
women. Methodology: the sample population is 40 apparently healthy young reproductive-aged 18- 25years
female students from the University of Medicine, Magway participated in this study. Systemic arterial blood
pressures were measured by indirect method. The serum magnesium level was measured by spectrophotometry.
These measurements were done in the early follicular phase (EF), the peri-ovulatory phase (PO), and the midluteal phase (ML) of the menstrual cycle. The serum magnesium levels were significantly (p <0.001) lower, and
the systolic blood pressures were significantly higher (p <0.05) in the PO than the EF and the ML. In the EF,
there was a significant negative correlation between serum magnesium level and diastolic blood pressure (r= -
0.374, p <0.05) and mean arterial pressure (r = -0.354, p < 0.05) but no significant correlation with systolic blood
pressure. In the PO, there was no significant correlation between serum magnesium level and systemic arterial
blood pressures. In the ML, there was significant negative correlation between serum magnesium level and
systolic blood pressure (r = -0.651, p <0.001), diastolic blood pressure (r = -0.607, p <0.001), and mean arterial
pressure (r = -0.661, p <0.001). Conclusion: The study concludes that serum magnesium level has a negative
effect on blood pressure changes and the blood pressure-lowering effect of magnesium. These changes are
related to the fluctuation of estrogen levels during the menstrual cycle.
KEYWORDS: Serum magnesium, systemic arterial blood pressures, menstrual cycle reproductive syste
Blind fault branching and propagation beneath Central Myanmar Basin revealed by high-resolution aftershock location and focal mechanism of the 2019 Mw5.5 YeU earthquake sequence
No full textAccurate and precise location and focal mechanism of aftershocks is a fundamental topic in seismology. However, nearfield seismic observations are usually not available for high-resolution source studies, or even when they are available high frequency waveform analyses are rarely conducted to extract more information. Here we study a unique dense nodal array data acquired by the deployment in the source region of the 2019 Mw5.5 strike-slip earthquake in Central Myanmar Basin (CMB). The network, composed of 20 nodal stations with station spacing of ~5km, was deployed ~2 weeks after the mainshock for ~ 40 days. We applied a machine learning based algorithm (Earthquake-Transformer) to detect 667 events from the dataset. Double difference relocation reveals that these events are distributed between 7 to 16 km in depth with a near E-W trending horizontal distribution, which is consistent with the left-lateral fault plane solution of the mainshock. On the vertical component of most of the stations, we observed a strong phase between P and S arrival times. This is an S-to-P converted phase from a sharp velocity boundary between the basin and the bedrock. The best 1D velocity model constrained by 3-component waveform modelling suggests a sedimentary layer thickness of ~3.5km beneath the stations. To determine the focal mechanism of aftershocks, we conducted high-frequency (up to a few Hz) waveform inversions that result in high quality waveform fits hence robust focal mechanisms of ~ 100 aftershocks with Mw1-2. In these focal mechanisms, ~50% are strike-slip events, ~40% are thrust events and ~10% are normal events, all corresponding to NE-SW oriented compressive stress. The thrust events have strikes oriented mostly in NW-SE direction and have dip angles of ~ 45°. Highly diverse aftershock focal mechanisms suggest the fault system is likely immature. The thrust and normal events indicate that the mainshock rupture had branched into or activated nearby secondary faults, which allow the strike-slip fault to propagate and develop a more complex fault system
Study of fault zone and basin structure of 2019 Mw5.5 Ye-U earthquake sequence beneath Central Myanmar Basin
No full textAccurate and precise location of earthquake sequence is critical to better understand seismotectonics, such as better delineation fault geometry and understanding of the rupture of the earthquakes. However, nearfield seismic observations are usually rare for such study. Here we study a unique dense nodal array data acquired by the deployment after the 31/08/2019 Mw5.5 crustal earthquake that is located ~50km to the west of Sagaing fault near Mandalay beneath ShweBo Central Myanmar Basin (CMB). The network, composed of 20 nodal stations with station spacing of ~5km, was deployed ~ 2 weeks after the mainshock and continuously recording for ~ 40 days. High quality waveforms containing clear P and S phase arrivals, and an interesting P-to-S phase converted at the basement of CMB were recorded for aftershocks. We applied a machine learning based automatic phase detection software (Earthquake-Transformer) to the dataset and detected 1143 events that were recorded by at least 3 stations. Double difference relocation of these aftershocks reveals a near E-W trending fault with a dimension of ~10km along strike and located between 7 to 12 km in depth. The strike of aftershock lineation is highly consistent with the focal mechanism derived from regional waveform inversion, indicating a left lateral strike-slip fault beneath CMB. Mainshock epicenter refined by a path calibration technique is located to the western edge of the seismicity, suggesting an eastward rupture directivity of the mainshock. Taking advantage of the P-basin-S converted phase at the basement of CMB, we constrained the thickness of the basin to be 5 ± 0.7 km. Strong strength of the P-basin-S phase requires sharp velocity change between the basin and bedrock. It is possible that the earthquake sequence is a result of small block rotation that has been taking place beneath the CMB due to the convergence of India plate. Another possible explanation is a conjugate fault system associated with 2012 Mw 6.8 Thabeikkyin earthquake sequence which ruptured close to Sagaing fault
Sustainability of a mobile phone application-based data reporting system in Myanmar’s malaria elimination program: a qualitative study
No full textAbstract Background Strengthening surveillance systems to collect near-real-time case-based data plays a fundamental role in achieving malaria elimination in the Greater Mekong Subregion (GMS). With the advanced and widespread use of digital technology, mHealth is increasingly taking a prominent role in malaria surveillance systems in GMS countries, including Myanmar. In Myanmar’s malaria elimination program, an mHealth system called Malaria Case-based Reporting (MCBR) has been applied for case-based reporting of malaria data by integrated community malaria volunteers (ICMVs). However, the sustainability of such mHealth systems in the context of existing malaria elimination programs in Myanmar is unknown. Methods Focus group discussions were conducted with ICMVs and semi-structured in-depth interviews were conducted with malaria program stakeholders from Myanmar’s Ministry of Health and Sports and its malaria program implementing partners. Thematic (deductive followed by inductive) analysis was undertaken using a qualitative descriptive approach. Results Technological and financial constraints such as inadequate internet access, software errors, and insufficient financial resources to support mobile phone-related costs have hampered users’ access to MCBR. Poor system integrity, unpredictable reporting outcomes, inadequate human resources for system management, and inefficient user support undermined the perceived quality of the system and user satisfaction, and hence its sustainability. Furthermore, multiple parallel systems with functions overlapping those of MCBR were in use. Conclusions Despite its effectiveness and efficiency in malaria surveillance, the sustainability of nationwide implementation of MCBR is uncertain. To make it sustainable, stakeholders should deploy a dedicated human workforce with the necessary technical and technological capacities; secure sustainable, long-term funding for implementation of MCBR; find an alternative cost-effective plan for ensuring sustainable system access by ICMVs, such as using volunteer-owned mobile phones for reporting rather than supporting new mobile phones to them; and find a solution to the burden of multiple parallel systems. Trial registration Not applicable
Sustainability of a Mobile Phone Application-Based Data Reporting System in Myanmar’s Malaria Elimination Program: A Qualitative Study
No full textSustainability of a Mobile Phone Application-Based Data Reporting System in Myanmar’s Malaria Elimination Program: A Qualitative Stud
A mobile phone application for malaria case-based reporting to advance malaria surveillance in Myanmar: a mixed methods evaluation
No full textBACKGROUND: To achieve malaria elimination in the Greater Mekong Subregion, including Myanmar, it is necessary to ensure all malaria cases are detected, treated, and reported in a timely manner. Mobile phone-based applications for malaria reporting, case management, and surveillance implemented at a community-level may overcome reporting limitations associated with current paper-based reporting (PBR), but their effectiveness in this context is unknown. METHODS: A mixed methods evaluation study was undertaken to determine the effectiveness of a national Malaria Case-Based Reporting (MCBR) mobile phone application in improving malaria case reporting compared to the existing PBR reporting system in Myanmar. Methods included secondary analysis of malaria case report data, questionnaires, focus group discussions and field observations of community volunteers, interviews and direct observations of malaria programme stakeholders, and cost analysis. Using a combination of these approaches the following areas were investigated: data quality and completeness, data access and usage, capacity for timely reporting, the acceptability, functionality, and ease of use of the application and facilitators and barriers to its use, and the relative cost of MCBR compared to the PBR system. RESULTS: Compared to PBR, MCBR enabled more accurate and complete data to be reported in a much timelier manner, with 63% of MCBR users reporting they transmit rapid diagnostic test outcomes within 24 h, compared to 0% of PBR users. MCBR was favoured by integrated community malaria volunteers and their supervisors because of its efficiency. However, several technical and operational challenges associated with internet coverage, data transmission, and e-literacy were identified and stakeholders reported not being confident to rely solely on MCBR data for programmatic decision-making. CONCLUSIONS: Implementation of MCBR provided timely and accurate data for malaria surveillance. Findings from this evaluation study will enable the optimization of an application-based reporting system for malaria monitoring and surveillance in the Greater Mekong Subregion and advance systems to track progress towards, and certify, the achievement of malaria elimination targets
Genomic epidemiology of artemisinin resistant malaria
No full textAbstract: The current epidemic of artemisinin resistant Plasmodium falciparum in Southeast Asia is the result of a soft selective sweep involving at least 20 independent kelch13 mutations. In a large global survey, we find that kelchl3 mutations which cause resistance in Southeast Asia are present at low frequency in Africa. We show that African kelch13 mutations have originated locally, and that kelch13 shows a normal variation pattern relative to other genes in Africa, whereas in Southeast Asia there is a great excess of non-synonymous mutations, many of which cause radical amino-acid changes. Thus, kelch13 is not currently undergoing strong selection in Africa, despite a deep reservoir of variations that could potentially allow resistance to emerge rapidly. The practical implications are that public health surveillance for artemisinin resistance should not rely on kelchl3 data alone, and interventions to prevent resistance must account for local evolutionary conditions, shown by genomic epidemiology to differ greatly between geographical regions
Molecular epidemiology of resistance to antimalarial drugs in the Greater Mekong subregion: an observational study
No full textBackground
The Greater Mekong subregion is a recurrent source of antimalarial drug resistance in Plasmodium falciparum malaria. This study aimed to characterise the extent and spread of resistance across this entire region between 2007 and 2018.
Methods
P falciparum isolates from Myanmar, Thailand, Laos, and Cambodia were obtained from clinical trials and epidemiological studies done between Jan 1, 2007, and Dec 31, 2018, and were genotyped for molecular markers (pfkelch, pfcrt, pfplasmepsin2, and pfmdr1) of antimalarial drug resistance. Genetic relatedness was assessed using microsatellite and single nucleotide polymorphism typing of flanking sequences around target genes.
Findings
10 632 isolates were genotyped. A single long pfkelch Cys580Tyr haplotype (from −50 kb to +31·5 kb) conferring artemisinin resistance (PfPailin) now dominates across the eastern Greater Mekong subregion. Piperaquine resistance associated with pfplasmepsin2 gene amplification and mutations in pfcrt downstream of the Lys76Thr chloroquine resistance locus has also developed. On the Thailand–Myanmar border a different pfkelch Cys580Tyr lineage rose to high frequencies before it was eliminated. Elsewhere in Myanmar the Cys580Tyr allele remains widespread at low allele frequencies. Meanwhile a single artemisinin-resistant pfkelch Phe446Ile haplotype has spread across Myanmar. Despite intense use of dihydroartemisinin–piperaquine in Kayin state, eastern Myanmar, both in treatment and mass drug administrations, no selection of piperaquine resistance markers was observed. pfmdr1 amplification, a marker of resistance to mefloquine, remains at low prevalence across the entire region.
Interpretation
Artemisinin resistance in P falciparum is now prevalent across the Greater Mekong subregion. In the eastern Greater Mekong subregion a multidrug resistant P falciparum lineage (PfPailin) dominates. In Myanmar a long pfkelch Phe446Ile haplotype has spread widely but, by contrast with the eastern Greater Mekong subregion, there is no indication of artemisinin combination therapy (ACT) partner drug resistance from genotyping known markers, and no evidence of spread of ACT resistant P falciparum from the east to the west. There is still a window of opportunity to prevent global spread of ACT resistance
Genetic architecture of artemisinin-resistant Plasmodium falciparum
No full textWe report a large multicenter genome-wide association study of Plasmodium falciparum resistance to artemisinin, the frontline antimalarial drug. Across 15 locations in Southeast Asia, we identified at least 20 mutations in kelch13 (PF3D7_1343700) affecting the encoded propeller and BTB/POZ domains, which were associated with a slow parasite clearance rate after treatment with artemisinin derivatives. Nonsynonymous polymorphisms in fd (ferredoxin), arps10 (apicoplast ribosomal protein S10), mdr2 (multidrug resistance protein 2) and crt (chloroquine resistance transporter) also showed strong associations with artemisinin resistance. Analysis of the fine structure of the parasite population showed that the fd, arps10, mdr2 and crt polymorphisms are markers of a genetic background on which kelch13 mutations are particularly likely to arise and that they correlate with the contemporary geographical boundaries and population frequencies of artemisinin resistance. These findings indicate that the risk of new resistance-causing mutations emerging is determined by specific predisposing genetic factors in the underlying parasite population
Spread of artemisinin resistance in Plasmodium falciparum malaria.
No full textBACKGROUND: Artemisinin resistance in Plasmodium falciparum has emerged in Southeast Asia and now poses a threat to the control and elimination of malaria. Mapping the geographic extent of resistance is essential for planning containment and elimination strategies. METHODS: Between May 2011 and April 2013, we enrolled 1241 adults and children with acute, uncomplicated falciparum malaria in an open-label trial at 15 sites in 10 countries (7 in Asia and 3 in Africa). Patients received artesunate, administered orally at a daily dose of either 2 mg per kilogram of body weight per day or 4 mg per kilogram, for 3 days, followed by a standard 3-day course of artemisinin-based combination therapy. Parasite counts in peripheral-blood samples were measured every 6 hours, and the parasite clearance half-lives were determined. RESULTS: The median parasite clearance half-lives ranged from 1.9 hours in the Democratic Republic of Congo to 7.0 hours at the Thailand-Cambodia border. Slowly clearing infections (parasite clearance half-life >5 hours), strongly associated with single point mutations in the "propeller" region of the P. falciparum kelch protein gene on chromosome 13 (kelch13), were detected throughout mainland Southeast Asia from southern Vietnam to central Myanmar. The incidence of pretreatment and post-treatment gametocytemia was higher among patients with slow parasite clearance, suggesting greater potential for transmission. In western Cambodia, where artemisinin-based combination therapies are failing, the 6-day course of antimalarial therapy was associated with a cure rate of 97.7% (95% confidence interval, 90.9 to 99.4) at 42 days. CONCLUSIONS: Artemisinin resistance to P. falciparum, which is now prevalent across mainland Southeast Asia, is associated with mutations in kelch13. Prolonged courses of artemisinin-based combination therapies are currently efficacious in areas where standard 3-day treatments are failing. (Funded by the U.K. Department of International Development and others; ClinicalTrials.gov number, NCT01350856.)
