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1.
Malar J ; 23(1): 71, 2024 Mar 09.
Article in English | MEDLINE | ID: mdl-38461239

ABSTRACT

BACKGROUND: Therapeutic efficacy studies (TESs) and detection of molecular markers of drug resistance are recommended by the World Health Organization (WHO) to monitor the efficacy of artemisinin-based combination therapy (ACT). This study assessed the trends of molecular markers of artemisinin resistance and/or reduced susceptibility to lumefantrine using samples collected in TES conducted in Mainland Tanzania from 2016 to 2021. METHODS: A total of 2,015 samples were collected during TES of artemether-lumefantrine at eight sentinel sites (in Kigoma, Mbeya, Morogoro, Mtwara, Mwanza, Pwani, Tabora, and Tanga regions) between 2016 and 2021. Photo-induced electron transfer polymerase chain reaction (PET-PCR) was used to confirm presence of malaria parasites before capillary sequencing, which targeted two genes: Plasmodium falciparum kelch 13 propeller domain (k13) and P. falciparum multidrug resistance 1 (pfmdr1). RESULTS: Sequencing success was ≥ 87.8%, and 1,724/1,769 (97.5%) k13 wild-type samples were detected. Thirty-seven (2.1%) samples had synonymous mutations and only eight (0.4%) had non-synonymous mutations in the k13 gene; seven of these were not validated by the WHO as molecular markers of resistance. One sample from Morogoro in 2020 had a k13 R622I mutation, which is a validated marker of artemisinin partial resistance. For pfmdr1, all except two samples carried N86 (wild-type), while mutations at Y184F increased from 33.9% in 2016 to about 60.5% in 2021, and only four samples (0.2%) had D1246Y mutations. pfmdr1 haplotypes were reported in 1,711 samples, with 985 (57.6%) NYD, 720 (42.1%) NFD, and six (0.4%) carrying minor haplotypes (three with NYY, 0.2%; YFD in two, 0.1%; and NFY in one sample, 0.1%). Between 2016 and 2021, NYD decreased from 66.1% to 45.2%, while NFD increased from 38.5% to 54.7%. CONCLUSION: This is the first report of the R622I (k13 validated mutation) in Tanzania. N86 and D1246 were nearly fixed, while increases in Y184F mutations and NFD haplotype were observed between 2016 and 2021. Despite the reports of artemisinin partial resistance in Rwanda and Uganda, this study did not report any other validated mutations in these study sites in Tanzania apart from R622I suggesting that intensified surveillance is urgently needed to monitor trends of drug resistance markers and their impact on the performance of ACT.


Subject(s)
Antimalarials , Artemisinins , Carubicin/analogs & derivatives , Malaria, Falciparum , Humans , Lumefantrine/pharmacology , Lumefantrine/therapeutic use , Plasmodium falciparum/genetics , Antimalarials/pharmacology , Antimalarials/therapeutic use , Tanzania , Artemisinins/pharmacology , Artemisinins/therapeutic use , Artemether/therapeutic use , Multidrug Resistance-Associated Proteins/genetics , Artemether, Lumefantrine Drug Combination/pharmacology , Artemether, Lumefantrine Drug Combination/therapeutic use , Malaria, Falciparum/epidemiology , Biomarkers , Drug Resistance/genetics , Protozoan Proteins/genetics , Protozoan Proteins/therapeutic use
2.
BMC Health Serv Res ; 24(1): 870, 2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39085821

ABSTRACT

BACKGROUND: Despite the global progress in bringing health services closer to the population, mothers and their newborns still receive substandard care leading to morbidity and mortality. Health facilities' capacity to deliver the service is a prerequisite for quality health care. This study aimed to assess health facilities' readiness to provide comprehensive emergency obstetric and newborn care (CEmONC), comprising of blood transfusion, caesarean section and basic services, and hence to inform improvement in the quality of care interventions in Tanzania. METHODS: A cross-sectional assessment of 30 CEmONC health facilities implementing the Safer Births Bundle of Care package in five regions of Tanzania was carried out between December 2020 and January 2021. We adapted the World Health Organization's Service Availability and Readiness Assessment tool to assess amenities, equipment, trained staff, guidelines, medicines, and diagnostic facilities. Composite readiness scores were calculated for each category and results were compared at the health facility level. For categorical variables, we tested for differences by Fisher's exact test; for readiness scores, differences were tested by a linear mixed model analysis, taking into account dependencies within the regions. We used p < 0.05 as our level of significance. RESULTS: The overall readiness to provide CEmONC was 69.0% and significantly higher for regional hospitals followed by district hospitals. Average readiness was 78.9% for basic amenities, 76.7% for medical equipment, 76.0% for diagnosis and treatment commodities, 63.6% for staffing and 50.0% for guidelines. There was a variation in the availability of items at the individual health facility level and across levels of facilities. We found a significant difference in the availability of basic amenities, equipment, staffing, and guidelines between regional, and district hospitals and health centres (p = 0.05). Regional hospitals had significantly higher scores of medical equipment than district hospitals and health centers (p = 0.02). There was no significant difference in the availability of commodities for diagnosis and treatment between different facility levels. CONCLUSION: Facilities' readiness was inadequate and varied across different levels of the facility. There is room to improve the facilities' readiness to deliver quality maternal and newborn care. The responsible authorities should take immediate actions to address the observed deficiencies while carefully choosing the most effective and feasible interventions and monitoring progress in readiness.


Subject(s)
Health Facilities , Humans , Tanzania , Cross-Sectional Studies , Female , Infant, Newborn , Pregnancy , Health Facilities/standards , Emergency Medical Services/standards , Emergency Medical Services/organization & administration , Quality of Health Care/standards
3.
BMC Health Serv Res ; 21(1): 1117, 2021 Oct 18.
Article in English | MEDLINE | ID: mdl-34663296

ABSTRACT

BACKGROUND: The burden of stillbirth, neonatal and maternal deaths are unacceptably high in low- and middle-income countries, especially around the time of birth. There are scarce resources and/or support implementation of evidence-based training programs. SaferBirths Bundle of Care is a well-proven package of innovative tools coupled with data-driven on-the-job training aimed at reducing perinatal and maternal deaths. The aim of this project is to determine the effect of scaling up the bundle on improving quality of intrapartum care and perinatal survival. METHODS: The project will follow a stepped-wedge cluster implementation design with well-established infrastructures for data collection, management, and analysis in 30 public health facilities in regions in Tanzania. Healthcare workers from selected health facilities will be trained in basic neonatal resuscitation, essential newborn care and essential maternal care. Foetal heart rate monitors (Moyo), neonatal heart rate monitors (NeoBeat) and skills trainers (NeoNatalie Live) will be introduced in the health facilities to facilitate timely identification of foetal distress during labour and improve neonatal resuscitation, respectively. Heart rate signal-data will be automatically collected by Moyo and NeoBeat, and newborn resuscitation training by NeoNatalie Live. Given an average of 4000 baby-mother pairs per year per health facility giving an estimate of 240,000 baby-mother pairs for a 2-years duration, 25% reduction in perinatal mortality at a two-sided significance level of 5%, intracluster correlation coefficient (ICC) to be 0.0013, the study power stands at 0.99. DISCUSSION: Previous reports from small-scale Safer Births Bundle implementation studies show satisfactory uptake of interventions with significant improvements in quality of care and lives saved. Better equipped and trained birth attendants are more confident and skilled in providing care. Additionally, local data-driven feedback has shown to drive continuous quality of care improvement initiatives, which is essential to increase perinatal and maternal survival. Strengths of this research project include integration of innovative tools with existing national guidelines, local data-driven decision-making and training. Limitations include the stepwise cluster implementation design that may lead to contamination of the intervention, and/or inability to address the shortage of healthcare workers and medical supplies beyond the project scope. TRIAL REGISTRATION: Name of Trial Registry: ISRCTN Registry. TRIAL REGISTRATION NUMBER: ISRCTN30541755 . Date of Registration: 12/10/2020. Type of registration: Prospectively Registered.


Subject(s)
Public Health , Resuscitation , Female , Humans , Infant , Infant, Newborn , Perinatal Mortality , Pregnancy , Stillbirth/epidemiology , Tanzania/epidemiology
4.
Amino Acids ; 52(5): 711-724, 2020 May.
Article in English | MEDLINE | ID: mdl-32318874

ABSTRACT

Erythrocytes have a well-defined role in the gaseous exchange of oxygen and carbon dioxide in the mammalian body. The erythrocytes can contain more than half of the free amino acids present in whole blood. Based on measures showing that venous erythrocyte levels of amino acids are much less than arterial erythrocyte levels, it has previously been proposed that erythrocytes also play a role in the delivery of amino acids to tissues in the body. This role has been dismissed because it has been assumed that to act as an amino acid transport vehicle, the erythrocytes should release their entire amino acid content in the capillary beds at the target tissues with kinetic studies showing that this would take too long to achieve. This investigation set out to investigate whether the equine erythrocytes could rapidly take up and release smaller packages of amino acids when exposed to high or low external concentrations of amino acids, because it seemed very unlikely that cells would be able to release all of their amino acids without serious impacts on osmotic balance. Freshly prepared erythrocytes were placed in alternating solutions of high and low amino acid concentrations in PBS to assess the capacities of these cells to rapidly take up and release amino acids depending on the nature of the external environment. It was found that amino acids were rapidly taken up and released in small quantities in each cycle representing 15% of their total load in equine erythrocytes and 16% in human erythrocytes. The capacity for rapid uptake/release of amino acids by equine and human erythrocytes provided evidence to support the theory that mammalian erythrocytes have a significant role in transport of amino acids from the liver to tissues, muscles and organs.


Subject(s)
Amino Acids/pharmacokinetics , Erythrocytes/metabolism , Liver/metabolism , Muscles/metabolism , Animals , Biological Transport , Horses , Humans , Liver/blood supply , Male , Middle Aged , Muscles/blood supply , Tissue Distribution
5.
Amino Acids ; 51(6): 945-959, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31028564

ABSTRACT

The nitrogen balance is regulated by factors such as diet, physical activity, age, pathogenic challenges, and climatic conditions. A paradigm was developed from published recommended rates of protein intake (g/kg/day) with corresponding rates of endogenous protein turnover and excretion, to extrapolate amino acid balances under various conditions. The average proportions of amino acids in the ingested proteins representing a well-balanced diet were used to assess intake and an average human composition profile from five major high-turnover proteins in the body to assess endogenous protein turnover. The amino acid excretion profiles for urine and sweat were constructed for males and females from published data. The model calculated the nitrogen balances for a range of amino acids to determine the amino acid requirements to support daily exertion. Histidine, serine, glycine, and ornithine were in negative balances in males and females and this potential deficit was greater in the higher body-mass ranges. Conversely, leucine, isoleucine, and valine were conserved during nitrogen flux and resulted in positive balances. The model was run under a scenario of high demand for the synthesis of IgG during a response to an infectious challenge which indicated that these were increased requirements for tyrosine, threonine, and valine. It was concluded that these amino acids represent points of limitation to anabolic metabolism by restriction of their supply at critical times of demand. This would especially occur under conditions of fitness training, maintaining intensive exercise regimes, facilitating responses to pathogenic challenge, or recovery from injury.


Subject(s)
Amino Acids/metabolism , Dietary Proteins/metabolism , Nitrogen Cycle/physiology , Amino Acids/urine , Female , Humans , Male , Models, Biological , Nitrogen/metabolism
6.
BMC Pediatr ; 19(1): 51, 2019 02 07.
Article in English | MEDLINE | ID: mdl-30732580

ABSTRACT

BACKGROUND: Newborn resuscitation is a life-saving intervention for birth asphyxia, a leading cause of neonatal mortality. Improving provider newborn resuscitation skills is critical for delivering quality care, but the retention of these skills has been a challenge. Tanzania implemented a national newborn resuscitation using the Helping Babies Breathe (HBB) training program to help address this problem. Our objective was to evaluate the effectiveness of two training approaches to newborn resuscitation skills retention implemented across 16 regions of Tanzania. METHODS: An initial training approach implemented included verbal instructions for participating providers to replicate the training back at their service delivery site to others who were not trained. After a noted drop in skills, the program developed structured on-the-job training guidance and included this in the training. The approaches were implemented sequentially in 8 regions each with nurses/ midwives, other clinicians and medical attendants who had not received HBB training before. Newborn resuscitation skills were assessed immediately after training and 4-6 weeks after training using a validated objective structured clinical examination, and retention, measured through degree of skills drop, was compared between the two training approaches. RESULTS: Eight thousand, three hundred and ninety-one providers were trained and assessed: 3592 underwent the initial training approach and 4799 underwent the modified approach. Immediately post-training, average skills scores were similar between initial and modified training groups: 80.5 and 81.3%, respectively (p-value 0.07). Both groups experienced statistically significant drops in newborn resuscitation skills over time. However, the modified training approach was associated with significantly higher skills scores 4-6 weeks post training: 77.6% among the modified training approach versus 70.7% among the initial training approach (p-value < 0.0001). Medical attendant cadre showed the greatest skills retention. CONCLUSIONS: A modified training approach consisting of structured OJT, guidance and tools improved newborn resuscitation skills retention among health care providers. The study results give evidence for including on-site training as part of efforts to improve provider performance and strengthen quality of care.


Subject(s)
Allied Health Personnel/education , Asphyxia Neonatorum/therapy , Clinical Competence , Inservice Training , Resuscitation/education , Humans , Infant , Infant, Newborn , Nurse Midwives/education , Nurses, Pediatric/education , Program Evaluation , Tanzania
7.
BMC Pregnancy Childbirth ; 18(1): 223, 2018 Jun 13.
Article in English | MEDLINE | ID: mdl-29895276

ABSTRACT

BACKGROUND: Tanzania has a maternal mortality ratio of 556 per 100,000 live births, representing 21% of all deaths of women of reproductive age. Hemorrhage, mostly postpartum hemorrhage (PPH), is estimated to cause at least 25% of maternal deaths in Tanzania. In 2008, the Ministry of Health, Community Development, Gender, Elderly and Children launched interventions to improve efforts to prevent PPH. Competency-based training for skilled birth attendants and ongoing quality improvement prioritized the practice of active management of the third stage of labor (AMTSL). METHODS: A cross-sectional study was conducted in 52 health facilities in Tanzania utilizing direct observations of women during labor and delivery. Observations were conducted in 2010 and, after competency-based training and quality improvement interventions in the facilities, in 2012. A total of 489 deliveries were observed in 2010 and 558 in 2012. Steps for AMTSL were assessed using a standardized structured observation checklist that was based on World Health Organization guidelines. RESULTS: The proportion of deliveries receiving all three AMTSL steps improved significantly by 19 percentage points (p < 0.001) following the intervention, with the most dramatic increase occurring in health centers and dispensaries (47.2 percentage point change) compared to hospitals (5.2 percentage point change). Use of oxytocin for PPH prevention rose by 37.1 percentage points in health centers and dispensaries but remained largely the same in hospitals, where the baseline was higher. There was substantial improvement in the timely provision of uterotonics (within 3 min of birth) across all facilities (p = 0.003). Availability of oxytocin, which was lower in health centers and dispensaries than hospitals at baseline, rose from 73 to 94% of all facilities. CONCLUSION: The quality of PPH prevention increased substantially in facilities that implemented competency-based training and quality improvement interventions, with the most dramatic improvement seen at lower-level facilities. As Tanzania continues with efforts to increase facility births, it is imperative that the quality of care also be improved by promoting use of up-to-date guidelines and ensuring regular training and mentoring for health care providers so that they adhere to the guidelines for care of women during labor. These measures can reduce maternal and newborn mortality.


Subject(s)
Delivery, Obstetric/adverse effects , Health Facilities/statistics & numerical data , Labor Stage, Third , Midwifery/methods , Postpartum Hemorrhage/prevention & control , Cross-Sectional Studies , Delivery, Obstetric/methods , Female , Health Services Accessibility/statistics & numerical data , Humans , Maternal Health Services/statistics & numerical data , Oxytocics/therapeutic use , Pregnancy , Tanzania
8.
Amino Acids ; 49(8): 1337-1345, 2017 08.
Article in English | MEDLINE | ID: mdl-28474126

ABSTRACT

Fluid collected during sweating is enriched with amino acids derived from the skin's natural moisturising factors and has been termed "faux" sweat. Little is known about sex differences in sweat amino acid composition or whether faux sweat amino acid losses affect nitrogen balance. Faux sweat collected by healthy adults (n = 47) after exercise, and at rest by chronic fatigue patients, was analysed for amino acid composition. Healthy females had higher total amino acid concentrations in sweat (10.5 ± 1.2 mM) compared with healthy males (6.9 ± 0.9 mM). Females had higher levels of 13 amino acids in sweat including serine, alanine and glycine. Higher hydroxyproline and proline levels suggested greater collagen turnover in females. Modelling indicated that with conservative levels of exercise, amino acid losses in females via faux sweat were triple than those predicted for urine, whereas in males they were double. It was concluded that females were more susceptible to key amino acid loss during exercise and/or hot conditions. Females reporting chronic fatigue had higher levels of methionine in faux sweat than healthy females. Males reporting chronic fatigue had higher levels of numerous amino acids in faux sweat compared to healthy males. Higher amino acid loss in faux sweat associated with chronic fatigue could contribute to a hypometabolic state. Depending on activity levels, climatic conditions and gender, amino acid losses in sweat and skin leachate could influence daily protein turnover where periods of continuously high turnover could lead to a negative net nitrogen balance.


Subject(s)
Amino Acids/metabolism , Collagen/metabolism , Exercise/physiology , Fatigue Syndrome, Chronic/physiopathology , Nitrogen/metabolism , Sweat/metabolism , Adolescent , Adult , Case-Control Studies , Female , Humans , Male , Sex Factors , Skin/metabolism , Water-Electrolyte Balance , Young Adult
9.
Nutr J ; 16(1): 19, 2017 03 23.
Article in English | MEDLINE | ID: mdl-28330481

ABSTRACT

BACKGROUND: The excretion of amino acids in urine represents an important avenue for the loss of key nutrients. Some amino acids such as glycine and histidine are lost in higher abundance than others. These two amino acids perform important physiological functions and are required for the synthesis of key proteins such as haemoglobin and collagen. METHODS: Stage 1 of this study involved healthy subjects (n = 151) who provided first of the morning urine samples and completed symptom questionnaires. Urine was analysed for amino acid composition by gas chromatography. Stage 2 involved a subset of the initial cohort (n = 37) who completed a 30 day trial of an amino acid supplement and subsequent symptom profile evaluation. RESULTS: Analyses of urinary amino acid profiles revealed that three groups could be objectively defined from the 151 participants using k-means clustering. The amino acid profiles were significantly different between each of the clusters (Wilks' Lambda = 0.13, p < 0.0001). Cluster 1 had the highest loss of amino acids with histidine being the most abundant component. Cluster 2 had glycine present as the most abundant urinary amino acid and cluster 3 had equivalent abundances of glycine and histidine. Strong associations were observed between urinary proline concentrations and fatigue/pain scores (r = .56 to .83) for females in cluster 1, with several other differential sets of associations observed for the other clusters. CONCLUSIONS: Different phenotypic subsets exist in the population based on amino acid excretion characteristics found in urine. Provision of the supplement resulted in significant improvements in reported fatigue and sleep for 81% of the trial cohort with all females reporting improvements in fatigue. TRIAL REGISTRATION: The study was registered on the 18th April 2011 with the Australian New Zealand Clinical Trials Registry ( ACTRN12611000403932 ).


Subject(s)
Amino Acids/administration & dosage , Amino Acids/urine , Dietary Supplements , Fatigue/drug therapy , Adolescent , Adult , Body Mass Index , Cluster Analysis , Cohort Studies , Female , Humans , Male , New Zealand , Surveys and Questionnaires , Young Adult
10.
Vet Pathol ; 51(1): 211-23, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24091812

ABSTRACT

Digital pathology, the practice of pathology using digitized images of pathologic specimens, has been transformed in recent years by the development of whole-slide imaging systems, which allow for the evaluation and interpretation of digital images of entire histologic sections. Applications of whole-slide imaging include rapid transmission of pathologic data for consultations and collaborations, standardization and distribution of pathologic materials for education, tissue specimen archiving, and image analysis of histologic specimens. Histologic image analysis allows for the acquisition of objective measurements of histomorphologic, histochemical, and immunohistochemical properties of tissue sections, increasing both the quantity and quality of data obtained from histologic assessments. Currently, numerous histologic image analysis software solutions are commercially available. Choosing the appropriate solution is dependent on considerations of the investigative question, computer programming and image analysis expertise, and cost. However, all studies using histologic image analysis require careful consideration of preanalytical variables, such as tissue collection, fixation, and processing, and experimental design, including sample selection, controls, reference standards, and the variables being measured. The fields of digital pathology and histologic image analysis are continuing to evolve, and their potential impact on pathology is still growing. These methodologies will increasingly transform the practice of pathology, allowing it to mature toward a quantitative science. However, this maturation requires pathologists to be at the forefront of the process, ensuring their appropriate application and the validity of their results. Therefore, histologic image analysis and the field of pathology should co-evolve, creating a symbiotic relationship that results in high-quality reproducible, objective data.


Subject(s)
Image Interpretation, Computer-Assisted/methods , Image Processing, Computer-Assisted/methods , Pathology, Veterinary/methods , Animals , Automation , Databases, Factual , Mice , Software , Telepathology/methods
11.
Healthcare (Basel) ; 12(3)2024 Jan 26.
Article in English | MEDLINE | ID: mdl-38338204

ABSTRACT

This paper examines changes in the completeness of documentation in clinical practice before and during the implementation of the Safer Births Bundle of Care (SBBC) project. This observational study enrolled parturient women with a gestation age of at least 28 weeks at the onset of labour. Data collectors extracted information from facility registers and then a central data manager summarised and reported weekly statistics. Variables of clinical significance for CQI were selected, and the proportion of non-documentation was analysed over time. A Pearson chi-square test was used to test for significant differences in non-documentation between the periods. Between 1 March 2021 and 31 July 2022, a total of 138,442 deliveries were recorded. Overall, 75% of all patient cases had at least one missing variable among the selected variables across both periods. A lack of variable documentation occurred more frequently at the district hospital level (81% of patient cases) and health centres (74%) than at regional referral hospitals (56%) (p < 0.001). Non-documentation decreased significantly from 79% to 70% after the introduction of the SBBC (p < 0.001). A tendency towards negative correlations was noted for most variables. We noted an increased attention to data quality and use which may have a positive impact on the completeness of documentation. However, halfway through the project's implementation, the completeness of documentation was still low. Our findings support the recommendation to establish short-spaced feedback loops of locally collected data using one data platform.

12.
Nutr J ; 12: 115, 2013 Aug 08.
Article in English | MEDLINE | ID: mdl-23927677

ABSTRACT

BACKGROUND: A new dietary supplement, Fatigue Reviva™, has been recently developed to address issues related to amino acid depletion following illness or in conditions of sub-health where altered amino acid homeostasis has been associated with fatigue. Complex formulations of amino acids present significant challenges due to solubility and taste constraints. This initial study sets out to provide an initial appraisal of product palatability and to gather pilot evidence for efficacy. METHODS: Males reporting symptoms of sub-health were recruited on the basis of being free from any significant medical or psychological condition. Each participant took an amino acid based dietary supplement (Fatigue Reviva™) daily for 30 days. Comparisons were then made between pre- and post-supplement general health symptoms and urinary amino acid profiles. RESULTS: Seventeen men took part in the study. Following amino acid supplementation the total Chalder fatigue score improved significantly (mean ± SEM, 12.5 ± 0.9 versus 10.0 ± 1.0, P<0.03). When asked whether they thought that the supplement had improved their health, 65% of participants responded positively. A subgroup of participants reported gastrointestinal symptoms which were attributed to the supplement and which were believed to result from the component fructooligosaccharide. Analysis of urinary amino acids revealed significant alterations in the relative abundances of a number of amino acids after supplementation including an increase in valine, isoleucine and glutamic acid and reduced levels of glutamine and ornithine. Discriminant function analysis of the urinary amino acid data revealed significant differences between the pre- and post-supplement urine excretion profiles. CONCLUSIONS: The results indicated that Fatigue Reviva™ was palatable and that 65% of the study group reported that they felt the product had improved their health. The product could provide an effective tool for the management of unexplained fatigue and symptoms of sub-health. Further product development may yield additional options for those patients susceptible to fructooligosaccharide.


Subject(s)
Amino Acids/administration & dosage , Dietary Supplements , Fatigue/drug therapy , Adult , Aged , Amino Acids/urine , Body Mass Index , Humans , Male , Middle Aged , Pilot Projects , Prospective Studies , Young Adult
13.
Ecotoxicology ; 19(8): 1440-51, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20700763

ABSTRACT

Although mounting evidence suggests exposure to estrogenic contaminants increases vitellogenin production in molluscs, demonstration of dose-response relationships and knowledge of the temporal nature of the vitellogenin response with continual exposure is currently lacking for biomarker utility. To address this knowledge gap, adult Sydney rock oysters, Saccostrea glomerata, were exposed to a range of environmentally relevant concentrations of 17α-ethynylestradiol (EE2) (0, 6.25, 12.5, 25 or 50 ng/l) in seawater under laboratory conditions. Vitellogenin induction and gonadal development was assessed following 4, 21 and 49 days exposure to EE2. Vitellogenin was found to increase in a dose dependent manner with EE2 exposure for females (4 and 49 days) and males (4 and 21 days). Histological examination of gonads revealed a number of individuals exhibited intersex (ovotestis) in 50 ng/l EE2 (after 21 days) and in 6.25 and 12.5 ng/l EE2 (after 49 days). Furthermore, a significant shift towards females was observed following 49 days exposure at 50 ng/l EE2 suggesting estrogenic exposure is capable of facilitating a progression for protandric males from male-intersex-female gametal status. Increases in female vitellogenin (4 days) were predictive of later increases in female developmental stages at 21 days and increases in oocyte area following 49 days. Male vitellogenin (4 days) was predictive of decreased male percentages and lower male developmental stages at 49 days. Vitellogenin in S. glomerata is a predictive biomarker of estrogenic exposure and effect if sampled soon after exposure and at the commencement of a gonadal development cycle.


Subject(s)
Ethinyl Estradiol/toxicity , Gonads/drug effects , Vitellogenins/drug effects , Water Pollutants, Chemical/toxicity , Animals , Biomarkers/metabolism , Disorders of Sex Development/chemically induced , Dose-Response Relationship, Drug , Estrogens/administration & dosage , Estrogens/toxicity , Ethinyl Estradiol/administration & dosage , Female , Gonads/growth & development , Male , Oocytes/drug effects , Oocytes/metabolism , Ostreidae/drug effects , Sex Factors , Time Factors , Vitellogenins/biosynthesis , Water Pollutants, Chemical/administration & dosage
14.
J Environ Monit ; 12(1): 255-60, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20082020

ABSTRACT

Microbial properties of harvested rainwater were assessed at two study sites at Newcastle on the east coast of Australia. The investigation monitored daily counts of heterotrophic bacteria (HPC), total coliforms and E. coli during a mid-winter month (July). Immediately after a major rainfall event, increases in bacterial loads were observed at both sites, followed by gradual reductions in numbers to prior baseline levels within 7 days. Baseline HPC levels ranged from 500-1000 cfu/mL for the sites evaluated, and the loads following rain peaked at 3590-6690 cfu/mL. Baseline levels of total coliforms ranged from 0-100 cfu/100 mL and peaked at 480-1200 cfu/100 mL following rain. At Site 1, there was no evidence of E. coli loading associated with the rain events assessed, and Site 2 had no detectable E.coli colonies at baseline, with a peak load of 17 cfu/100 mL following rain which again diminished to baseline levels. It was concluded that rainfall events contributed to the bacterial load in rainwater storage systems, but processes within the rainwater storage ensured these incoming loads were not sustained.


Subject(s)
Bacteria/isolation & purification , Environmental Monitoring , Rain , Water Microbiology , Australia , Bacteria/growth & development , Bacteria/metabolism , Biodiversity , Ecosystem , Enterobacteriaceae/growth & development , Enterobacteriaceae/isolation & purification , Enterobacteriaceae/metabolism , Escherichia coli/growth & development , Escherichia coli/isolation & purification , Escherichia coli/metabolism , Geography , Seasons , Soil Microbiology , Time Factors , Water Pollutants/analysis
15.
Water Sci Technol ; 61(1): 25-36, 2010.
Article in English | MEDLINE | ID: mdl-20057088

ABSTRACT

Chemical qualities of harvested rainwater were assessed at two residential study sites on the east coast of Australia in relation to coastal proximity and surrounding land uses over the course of a winter and summer month. Daily rainwater samples were collected from the base outlet and surface levels of stored water for chemical analyses. High resolution inductively coupled plasma-mass spectrometry (ICP-MS) was used to analyse 26 elements in all samples. The summer sampling regime for the industrial coastal Site 1 was dominated by wind gusts originating from the east with a total average elemental load of 25,900+/-17,000 microg/L compared to the significantly lower 10,600+/-3,370 microg/L measured during the winter month, where 84% of wind gust events originated from the west. Data for the inland Site 2, with no proximity to industry, revealed no significant changes in total average loads between the winter (4,870+/-578 microg/L) and summer (4,760+/-2,280 microg/L) months. The most abundant elements found at both sites included Na, K, Mg, and Zn. The rainwater storages at Site 2 fed from a relatively new concrete tiled roof catchment had significantly lower pH and conductivity measurements compared with those at Site 1 with an old galvanised iron roof catchment. It was concluded that seasonal differences in harvested water quality were likely influenced by prevailing wind direction and external influences such as surrounding land uses and proximity to the coast.


Subject(s)
Seasons , Water Supply/analysis , Australia , Climate , Magnesium/analysis , Meteorology , Potassium/analysis , Rain , Sodium/analysis , Surface Plasmon Resonance/methods , Wind , Zinc/analysis
16.
PLoS One ; 15(1): e0226988, 2020.
Article in English | MEDLINE | ID: mdl-31899789

ABSTRACT

Horses in heavy training in preparation for racing and competition have increased metabolic demands to support the more intensive levels of exercise and recovery. However, little is known at the metabolic level about amino acid turnover and the specific alterations of demand caused by high intensity exercise. During exercise, certain amino acids are required in greater quantities due to disproportionate losses via excretory systems and usage in biosynthetic pathways. This investigation has built a theoretical computer model in an attempt to bring together the published rates of protein intake and utilisation to try to understand how some amino acids might be in higher demand than others. The model indicated that after evaluation of the daily amino acid turnover, glutamine/glutamic acid (Glx), serine and ornithine were in negative nitrogen balance which identified these amino acids as critical limiting factors for anabolism. Adjustment of the modelling conditions to cater for high intensity training indicated that an additional demand was placed on eight amino acids, including GLx, valine, lysine, histidine and phenylalanine which could thus become limiting under these conditions. The modelling results indicated that an amino acid supplement with the correct amino acids to match demand could theoretically be beneficial to a 500Kg horse in quantities of 20-80g/day. These results open new avenues of research for specifically tailoring amino acid supplementation to meet demands for sports horses in heavy training and improving general well-being, especially in hotter climates.


Subject(s)
Amino Acids/metabolism , Dietary Supplements , Physical Conditioning, Animal , Animals , Computer Simulation , Homeostasis , Horses , Models, Theoretical , Nitrogen/metabolism
17.
Microorganisms ; 8(7)2020 Jul 20.
Article in English | MEDLINE | ID: mdl-32698515

ABSTRACT

The pathogenesis of Staphylococcus aureus is mainly attributed to its capability to adjust to changes in environmental conditions, including those present on human skin or within a wound site. This study investigated the changes in the cytoplasmic and secreted proteins in S. aureus that occurred in response to alterations in the environmental parameters that could be found in the human wound site. In total, sixty differentially regulated cytoplasmic proteins were detected using a label-free quantification approach, and these proteins were classified into ten molecular functions: protein biosynthesis, glycolysis, signal transduction, metabolism, cell cycle, transport, energy generation, cell anchorage, nucleotide biosynthesis and unknown. These changes represented characteristic protein profiles when evaluated by principal component analysis. The bacterium responded to elevated NaCl at pH 6 by decreasing the abundance of the majority of cytoplasmic proteins, while at pH 8 there was an increase in the levels of cytoplasmic proteins in comparison to the untreated cells. The analysis of the secreted proteins showed that there was a high degree of difference in both the intensity and the distribution of many individual protein bands in response to environmental challenges. From these results, it was deduced that specific metabolic homeostasis occurred under each combination of defined environmental conditions.

18.
Sci Total Environ ; 742: 140449, 2020 Nov 10.
Article in English | MEDLINE | ID: mdl-32640399

ABSTRACT

Pesticides are frequently employed to enhance agricultural production. Neonicotinoid pesticides (including imidacloprid) are often used to control sucking insects but have been shown to impact aquatic crustaceans. Imidacloprid is highly water soluble and has been detected in estuaries where it has been applied in adjacent catchments. We examined the impact of environmentally relevant concentrations of imidacloprid on Eastern School Prawn (Metapenaeus macleayi), an important exploited crustacean in Australia. Prawns were held for 8 days in estuarine water containing 0-4 µg L-1 of imidacloprid to assess potential lethal and non-lethal impacts. There was a non-linear relationship between exposure concentration and tissue concentration, with tissue concentrations peaking at exposures of 1.4 µg L-1 (1.16 to 1.64 µg L-1, 90% C.I.). There was no evidence for direct mortality associated with imidacloprid exposure, but exposure did influence the organism metabolome which likely reflects alterations in metabolic homeostasis, such as changes in the fatty acid composition which indicate a shift in lipid homeostasis. There was a positive correlation between exposure concentration and moulting frequency. Shedding of the exoskeleton may represent a mechanism through which prawns can expel the contaminant from their bodies. These results indicate that prawns experience several different sub-lethal effects when exposed to these pesticides, which may have implications for the health of populations.


Subject(s)
Insecticides , Penaeidae , Pesticides , Water Pollutants, Chemical/analysis , Animals , Australia , Neonicotinoids , Nitro Compounds
19.
Obes Sci Pract ; 6(2): 171-180, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32313675

ABSTRACT

BACKGROUND: In the last decade, Tanzania has observed a dramatic increase in overweight and obesity among women of childbearing age, a demographic shift that has been associated with intrapartum obstetric complications in high-income countries. Similar increases in maternal morbidity including postpartum haemorrhage, hypertensive disorders of pregnancy, and rates of caesarean delivery have not yet documented in Tanzania. This analysis describes intrapartum obstetric complications associated with maternal obesity among pregnant women delivering at teaching hospital in Northern Tanzania. METHODS: A retrospective cohort analysis was conducted using the hospital's antenatal care (ANC) and birth registries from 2000 to 2015. The World Health Organization (WHO) body mass index (BMI) categories were applied to classify BMI status of pregnant women within 16 weeks of gestational age at their first ANC visit. Relative risk (RR) of obstetric complications with corresponding 95% confidence intervals (CIs) were estimated using multivariable log-binomial regression, adjusting for clustering effect for the correlation between multiple deliveries of the same woman. RESULTS: Among 11 873 women who delivered babies in the hospital during the study period, 3139 (26.5%) fit the definition of overweight and 1464 (12.3%) women with obesity. Compared with women with normal weight, women with obesity were at over 2.6 times at risks of experiencing pre-eclampsia/eclampsia (RR: 2.66; 95% CI, 2.08-3.40), pregnancy-induced hypertension (RR 2.13; 95% CI, 1.26-3.62), and postpartum haemorrhage (RR 1.22; 95% CI, 1.00-1.49). Additionally, women with obesity had also higher risk of either elective (RR 2.40; 95% CI, 1.88-3.06) or emergency (RR: 1.53; 95% CI, 1.34-1.75) caesarean delivery. CONCLUSION: Maternal obesity is an emerging health problem in Tanzania. This study clearly demonstrates an association between increased risk of intrapartum complications and obesity. A review of guidelines around ANC screening and intrapartum care practices considering BMI, as well as appropriate messages for women with obesity, should be considered to improve maternal and newborn outcomes.

20.
Br J Dermatol ; 161(2): 265-72, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19438474

ABSTRACT

BACKGROUND: Congenital, nonepidermolytic cornification disorders phenotypically resembling human autosomal recessive ichthyosis have been described in purebred dog breeds, including Jack Russell terrier (JRT) dogs. One cause of gene mutation important to humans and dogs is transposon insertions. OBJECTIVES: To describe an autosomal recessive, severe nonepidermolytic ichthyosis resembling lamellar ichthyosis (LI) in JRT dogs due to insertion of a long interspersed nucleotide element (LINE-1) in the transglutaminase 1 (TGM1) gene. METHODS: Dogs were evaluated clinically, and skin samples were examined by light and electron microscopy. Phenotypic information and genotyping with a canine microsatellite marker suggested TGM1 to be a candidate gene. Genomic DNA samples and cDNA generated from epidermal RNA were examined. Consequences of the mutation were evaluated by Western blotting, quantitative reverse transcription-polymerase chain reaction (RT-PCR) and enzyme activity from cultured keratinocytes. RESULTS: Affected dogs had generalized severe hyperkeratosis. Histological examination defined laminated to compact hyperkeratosis without epidermolysis; ultrastructurally, cornified envelopes were thin. Affected dogs were homozygous for a 1980-bp insertion within intron 9 of TGM1. The sequence of the insertion was that of a canine LINE-1 element. Quantitative RT-PCR indicated a significant decrease in TGM1 mRNA in affected dogs compared with wild-type. TGM1 protein was markedly decreased on immunoblotting, and membrane-associated enzyme activity was diminished in affected dogs. CONCLUSIONS: Based on morphological and molecular features, this disease is homologous with TGM1-deficient LI in humans, clinically models LI better than the genetically modified mouse and represents its first spontaneous animal model. This is the first reported form of LI due to transposon insertion.


Subject(s)
Dog Diseases/genetics , Ichthyosis, Lamellar/veterinary , Long Interspersed Nucleotide Elements/genetics , Mutagenesis, Insertional/genetics , Transglutaminases/genetics , Animals , Biopsy/veterinary , DNA Transposable Elements/genetics , Dog Diseases/pathology , Dogs , Female , Genetic Markers , Ichthyosis, Lamellar/genetics , Ichthyosis, Lamellar/pathology , Immunohistochemistry , Introns/genetics , Male , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction/veterinary , Skin/pathology , Species Specificity , Transglutaminases/deficiency , Transglutaminases/metabolism
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