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1.
Article in English | MEDLINE | ID: mdl-38782573

ABSTRACT

BACKGROUND: Identification of multiple sclerosis (MS) cases in routine healthcare data repositories remains challenging. MS can have a protracted diagnostic process and is rarely identified as a primary reason for admission to the hospital. Difficulties in identification are compounded in systems that do not include insurance or payer information concerning drug treatments or non-notifiable disease. AIM: To develop an algorithm to reliably identify MS cases within a national health data bank. METHOD: Retrospective analysis of the Secure Anonymised Information Linkage (SAIL) databank was used to identify MS cases using a novel algorithm. Sensitivity and specificity were tested using two existing independent MS datasets, one clinically validated and population-based and a second from a self-registered MS national registry. RESULTS: From 4 757 428 records, the algorithm identified 6194 living cases of MS within Wales on 31 December 2020 (prevalence 221.65 (95% CI 216.17 to 227.24) per 100 000). Case-finding sensitivity and specificity were 96.8% and 99.9% for the clinically validated population-based cohort and sensitivity was 96.7% for the self-declared registry population. DISCUSSION: The algorithm successfully identified MS cases within the SAIL databank with high sensitivity and specificity, verified by two independent populations and has important utility in large-scale epidemiological studies of MS.

2.
Open Forum Infect Dis ; 11(4): ofae098, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38560601

ABSTRACT

Background: Despite the high frequency of adrenal insufficiency (AI) in patients with tuberculosis or HIV, its diagnosis is often missed or delayed resulting in increased mortality. This systematic review and meta-analysis aimed to document the prevalence, significant clinical features, and predictors of AI in adult patients with tuberculosis or HIV. Methods: We systematically searched databases (Medline, Embase, CINAHL, Cochrane Library, and Africa Journal Online) for published studies on AI in adult patients with tuberculosis or HIV. The pooled prevalence of AI was determined by a random-effect model meta-analysis. A narrative review was used to describe the significant clinical features and predictors of AI in adult patients with tuberculosis or HIV. Results: A total of 46 studies involving 4044 adults were included: 1599 with tuberculosis and 2445 with HIV. The pooled prevalence of AI was 33% (95% CI, 22%-45%; I2 = 97.7%, P < .001) in participants with tuberculosis and 28% (95% CI, 18%-38%; I2 = 98.9%, P < .001) in those with HIV. Presentation with multidrug-resistant tuberculosis, abdominal pain, salt craving, myalgia, increased severity and duration of tuberculosis disease, and the absence of nausea predicted AI in participants with tuberculosis in 4 studies. Cytomegalovirus antigenemia positivity, rifampicin therapy, and eosinophilia >3% predicted AI in participants with HIV in 2 studies. Conclusions: AI is relatively common in adults with tuberculosis or HIV. Its timely screening, diagnosis, and management in patients with these 2 conditions should be encouraged to avert mortality.

3.
Br J Anaesth ; 132(5): 1041-1048, 2024 May.
Article in English | MEDLINE | ID: mdl-38448274

ABSTRACT

BACKGROUND: Regional anaesthesia use is growing worldwide, and there is an increasing emphasis on research in regional anaesthesia to improve patient outcomes. However, priorities for future study remain unclear. We therefore conducted an international research prioritisation exercise, setting the agenda for future investigators and funding bodies. METHODS: We invited members of specialist regional anaesthesia societies from six continents to propose research questions that they felt were unanswered. These were consolidated into representative indicative questions, and a literature review was undertaken to determine if any indicative questions were already answered by published work. Unanswered indicative questions entered a three-round modified Delphi process, whereby 29 experts in regional anaesthesia (representing all participating specialist societies) rated each indicative question for inclusion on a final high priority shortlist. If ≥75% of participants rated an indicative question as 'definitely' include in any round, it was accepted. Indicative questions rated as 'definitely' or 'probably' by <50% of participants in any round were excluded. Retained indicative questions were further ranked based on the rating score in the final Delphi round. The final research priorities were ratified by the Delphi expert group. RESULTS: There were 1318 responses from 516 people in the initial survey, from which 71 indicative questions were formed, of which 68 entered the modified Delphi process. Eleven 'highest priority' research questions were short listed, covering themes of pain management; training and assessment; clinical practice and efficacy; technology and equipment. CONCLUSIONS: We prioritised unanswered research questions in regional anaesthesia. These will inform a coordinated global research strategy for regional anaesthesia and direct investigators to address high-priority areas.


Subject(s)
Anesthesia, Conduction , Biomedical Research , Humans , Delphi Technique , Surveys and Questionnaires , Research Design
4.
Acta Obstet Gynecol Scand ; 103(3): 413-422, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38037500

ABSTRACT

INTRODUCTION: Women with a prior stillbirth or a history of recurrent first trimester miscarriages are at increased risk of adverse pregnancy outcomes. However, little is known about the impact of a second trimester pregnancy loss on subsequent pregnancy outcome. This review investigated if second trimester miscarriage or termination for medical reason or fetal anomaly (TFMR/TOPFA) is associated with future adverse pregnancy outcomes. MATERIAL AND METHODS: A systematic review of observational studies was conducted. Eligible studies included women with a history of a second trimester miscarriage or termination for medical reasons and their pregnancy outcomes in the subsequent pregnancy. Where comparative studies were identified, studies which compared subsequent pregnancy outcomes for women with and without a history of second trimester loss or TFMR/TOPFA were included. The primary outcome was livebirth, and secondary outcomes included: miscarriage (first and second trimester), termination of pregnancy, fetal growth restriction, cesarean section, preterm birth, pre-eclampsia, antepartum hemorrhage, stillbirth and neonatal death. Studies were excluded if exposure was nonmedical termination or if related to twins or higher multiple pregnancies. Electronic searches were conducted using the online databases (MEDLINE, Embase, PubMed and The Cochrane Library) and searches were last updated on June 16, 2023. Risk of bias was assessed using the Newcastle-Ottawa scale. Where possible, meta-analysis was undertaken. PROSPERO registration: CRD42023375033. RESULTS: Ten studies were included, reporting on 12 004 subsequent pregnancies after a second trimester pregnancy miscarriage. No studies were found on outcomes after second trimester TFMR/TOPFA. Overall, available data were of "very low quality" using GRADE assessment. Meta-analysis of cohort studies generated estimated outcome frequencies for women with a previous second trimester loss as follows: live birth 81% (95% CI: 64-94), miscarriage 15% (95% CI: 4-30, preterm birth 13% [95% CI: 6-23]).The pooled odds ratio for preterm birth in subsequent pregnancy after second trimester loss in case-control studies was OR 4.52 (95% CI: 3.03-6.74). CONCLUSIONS: Very low certainty evidence suggests there may be an increased risk of preterm birth in a subsequent pregnancy after a late miscarriage. However, evidence is limited. Larger, higher quality cohort studies are needed to investigate this potential association.


Subject(s)
Abortion, Habitual , Abortion, Spontaneous , Premature Birth , Pregnancy , Female , Infant, Newborn , Humans , Pregnancy Outcome , Abortion, Spontaneous/epidemiology , Pregnancy Trimester, Second , Stillbirth/epidemiology , Premature Birth/epidemiology , Premature Birth/etiology , Cesarean Section/adverse effects
5.
Clin Microbiol Infect ; 30(5): 592-600, 2024 May.
Article in English | MEDLINE | ID: mdl-38145865

ABSTRACT

BACKGROUND: Fungal infections are common in HIV-infected individuals and significantly contribute to mortality. However, a substantial number of cases are undiagnosed before death. OBJECTIVE: To determine the frequency of fungal pathogens in autopsy studies of people who died with HIV in Africa. METHODS: We conducted a scoping review of autopsy studies conducted in Africa. DATA SOURCES: PubMed, Scopus, Web of Science, Embase, Google Scholar, and African Journal Online. STUDY ELIGIBILITY CRITERIA: The review encompasses studies published from inception to September 2023, and no language restrictions were imposed during the search process. We included studies that reported histopathological or microbiological evidence for the diagnosis of fungal infections and other pathogens. DATA SYNTHESIS: Data were summarized using descriptive statistics and no meta-analysis was performed. RESULTS: We examined 30 articles reporting studies conducted between 1991 and 2019, encompassing a total of 13 066 HIV-infected decedents across ten African countries. In five studies, the autopsy type was not specified. Among those studies with specified autopsy types, 20 involved complete diagnostic autopsies, whereas 5 were categorized as partial or minimally invasive autopsies. There were 2333 pathogens identified, with 946 (40.5%) being mycobacteria, 856 (36.7%) fungal, 231 (3.8%) viral, 208 (8.9%) parasitic, and 92 (3.9%) bacterial. Of the 856 fungal pathogens identified, 654 (28.0%) were Cryptococcus species, 167 (7.2%) Pneumocystis jirovecii, 16 (0.69%) Histoplasma species, 15 (0.64%) Aspergillus species, and 4 (0.17%) Candida species. Other major non-fungal pathogens identified were cytomegalovirus 172 (7.37%) and Toxoplasma gondii 173 (7.42%). CONCLUSIONS: Invasive fungal infections occur in over one-third of people who succumb to HIV in Africa. In addition to cryptococcosis and Pneumocystis jirovecii pneumonia, integrating other priority fungal pathogen detection and management strategies into the broader framework of HIV care in Africa is recommended. This involves increasing awareness regarding the impact of fungal infections in advanced HIV disease and strengthening diagnostic and treatment capacity.


Subject(s)
Autopsy , HIV Infections , Mycoses , Humans , Africa/epidemiology , HIV Infections/complications , Mycoses/epidemiology , Mycoses/microbiology , Mycoses/mortality , Fungi/isolation & purification , Fungi/classification , AIDS-Related Opportunistic Infections/microbiology , AIDS-Related Opportunistic Infections/mortality , AIDS-Related Opportunistic Infections/epidemiology
6.
J Lipid Res ; 65(1): 100484, 2024 01.
Article in English | MEDLINE | ID: mdl-38103786

ABSTRACT

Aminophospholipids (aPL) such as phosphatidylserine are essential for supporting the activity of coagulation factors, circulating platelets, and blood cells. Phosphatidylthreonine (PT) is an aminophospholipid previously reported in eukaryotic parasites and animal cell cultures, but not yet in human tissues. Here, we evaluated whether PT is present in blood cells and characterized its ability to support coagulation. Several PT molecular species were detected in human blood, washed platelets, extracellular vesicles, and isolated leukocytes from healthy volunteers using liquid chromatography-tandem mass spectrometry. The ability of PT to support coagulation was demonstrated in vitro using biochemical and biophysical assays. In liposomes, PT supported prothrombinase activity in the presence and absence of phosphatidylserine. PT nanodiscs strongly bound FVa and lactadherin (nM affinity) but poorly bound prothrombin and FX, suggesting that PT supports prothrombinase through recruitment of FVa. PT liposomes bearing tissue factor poorly generated thrombin in platelet poor plasma, indicating that PT poorly supports extrinsic tenase activity. On platelet activation, PT is externalized and partially metabolized. Last, PT was significantly higher in platelets and extracellular vesicle from patients with coronary artery disease than in healthy controls. In summary, PT is present in human blood, binds FVa and lactadherin, supports coagulation in vitro through FVa binding, and is elevated in atherosclerotic vascular disease. Our studies reveal a new phospholipid subclass, that contributes to the procoagulant membrane, and may support thrombosis in patients at elevated risk.


Subject(s)
Coronary Artery Disease , Glycerophospholipids , Threonine/analogs & derivatives , Thromboplastin , Animals , Humans , Thromboplastin/metabolism , Phosphatidylserines/metabolism , Liposomes/metabolism , Blood Platelets/metabolism , Thrombin/metabolism
7.
Ther Adv Urol ; 15: 17562872231218621, 2023.
Article in English | MEDLINE | ID: mdl-38130371

ABSTRACT

Background: Aspergillosis localized to the kidneys and the urinary tract is uncommon. We conducted a comprehensive systematic review to evaluate risk factors and clinical outcomes of patients with isolated renal and genito-urinary tract aspergillosis. Methods: We systematically searched Medline, CINAHL, Embase, African Journal Online, Google Scholar, and the Cochrane Library, covering the period from inception to August 2023 using the key terms 'renal' OR 'kidney*' OR 'prostate' OR 'urinary bladder' OR 'urinary tract*AND 'aspergillosis' OR 'aspergillus' OR 'aspergilloma' OR 'mycetoma'. We included single case reports or case series. Review articles, guidelines, meta-analyses, animal studies, protocols, and cases of genitourinary and /or renal aspergillosis occurring as a part of disseminated disease were excluded. Results: We identified 91 renal and urinary aspergillosis cases extracted from 76 publications spanning 1925-2023. Among the participants, 79 (86.8%) were male, with a median age of 46 years. Predominantly, presentations consisted of isolated renal infections (74 instances, 81.3%), followed by prostate (5 cases, 5.5%), and bladder (7 cases, 7.7%) involvement. Aspergillus fumigatus (42.9%), Aspergillus flavus (9.9%), and Aspergillus niger/glaucus (1.1% each) were isolated. Underlying risk factors included diabetes mellitus (29.7%), HIV (12.1%), haematological malignancies (11%), and liver cirrhosis (8.8%), while common symptoms encompassed flank pain (36.3%), fever (33%), and lower urinary tract symptoms (20.9%). An autopsy was conducted in 8.8% of cases. Diagnostic work-up involved histopathology (70.5%), renal CT scans and urine microscopy and culture (52.6% each), and abdominal ultrasound (17.9%). Treatments included amphotericin B (34 cases, 37.4%) and azole-based regimens (29 cases, 31.9%). Nephrectomy was performed in 16 of 78 renal cases (20.5%). All-cause mortality was 24.4% (19 cases). No significant mortality rate difference was observed among antifungal regimens (p = 0.739) or nephrectomy status (p = 0.8). Conclusion: Renal and urinary aspergillosis is an important cause of morbidity and mortality, particularly in immunocompromised and people with diabetes mellitus. While varied treatment strategies were observed, mortality rates showed no significant differences based on treatments or nephrectomy status. Further research is needed to refine diagnostics, optimize treatments, and enhance awareness among clinicians for early detection and management. PROSPERO registration number: CRD42023430959.


What you need to know now about kidney and urinary tract infections caused by the fungus aspergillus In this study, we investigated the rare occurrence of aspergillosis, a fungal infection caused by the mold Aspergillus, specifically affecting the kidneys and urinary tract (ureters, urinary bladder, prostate and urethra). This disease was first described in 1891 in Germany. To update our current understanding of this rare disease, we conducted a thorough review, examining risk factors and outcomes for individuals with Aspergillus infection of the kidney and/or urinary tract. We found 91 cases from 76 published articles spanning nearly a century, identifying common features such as predominantly male patients (almost every 9 in 10 cases) and isolated infection of one or both kidneys being the most common (8 in 10 cases). Diabetes mellitus, HIV infection, and certain cancers were noted as underlying risk factors, with symptoms ranging from flank pain, passing of blood in urine, passing of fungal particles (bezoars) in urine, pain while passing urine to fever. Diagnostic methods included histopathology and imaging techniques, while treatments varied, involving antifungal medications such as voriconazole and amphotericin B, drainage of abscesses, and, in some cases, surgical removal of the affected kidney (nephrectomy). Overall, about 1 in every 4 of the affected people died. Despite diverse treatment approaches, the study found no significant difference in mortality rates, emphasizing the need for further research to improve diagnostics, refine treatments, and raise awareness for early detection and management, especially among immunocompromised individuals such as those with diabetes mellitus and HIV infection.

8.
Article in English | MEDLINE | ID: mdl-38248512

ABSTRACT

'iSupport' is an online psychoeducation and skills development intervention created by the World Health Organisation to support people with dementia. This project adapted iSupport for carers of people with rare dementias (iSupport RDC), creating a new resource to support the health and wellbeing of this underserved population. The adaptation involved three phases: (1) Co-design methods to generate preliminary adaptations; (2) Analysis of phase one findings informing adaptations to iSupport to develop; iSupport RDC; (3) Post-adaptation survey to ascertain participant agreement with the adaptations in iSupport RDC. Fourteen participants contributed, resulting in 212 suggested adaptations, of which 94 (92%) were considered practical, generalisable, and aligned with iSupport principles. These adaptations encompassed content and design changes, including addressing the challenges of rare dementias (PCA, PPA, LBD, and FTD). iSupport RDC represents a significant adaptation of the WHO iSupport intervention. Its tailored nature acknowledges the unique needs of people caring for someone with a rare dementia, improving their access to specialised resources and support. By extending iSupport to this population, it contributes to advancing dementia care inclusivity and broadening the understanding of rare dementias. A feasibility study is underway to assess iSupport RDCs acceptability, with prospects for cultural adaptations to benefit carers globally.


Subject(s)
Conjunctival Diseases , Corneal Diseases , Dementia , Dermoid Cyst , Telemedicine , Humans , Caregivers
9.
J Med Internet Res ; 24(7): e36727, 2022 07 22.
Article in English | MEDLINE | ID: mdl-35867388

ABSTRACT

BACKGROUND: The prevalence of dementia is increasing, and there are many associated problems that family members face as informal carers, including emotional, physical, and financial difficulties. There are benefits for a person with dementia to live at home for as long as possible, and therefore, supporting their informal carers is crucial. The growing interest in supporting carers through internet-based interventions is evidenced by the volume of systematic reviews on this topic. It is now appropriate to systematically examine this body of work and provide an overview of the literature. OBJECTIVE: This umbrella review aimed to identify the most effective internet-based intervention content and delivery method to support those caring for someone with dementia living in the community. METHODS: PsycINFO, Web of Science, CINAHL, MEDLINE, Cochrane Library, and PubMed were searched for systematic reviews examining the effectiveness of web-based interventions for informal carers of people with dementia. A total of 3 reviewers extracted data and evaluated the quality of the papers. To ascertain the extent to which the systematic reviews reported on the same evidence, the proportion of overlap between their included studies was calculated. Qualitative research findings were extracted and reported. RESULTS: A total of 21 papers were included in the study. The quality of the review papers was mainly rated as low to moderate, and 10% (2/21) of papers were of high quality. The findings suggest that multicomponent interventions were the most effective in supporting carers. These included combinations of cognitive behavioral therapy and relaxation strategies, educational resources, and online support groups. Interventions that were delivered on the web but included sessions with a personal element, such as telephone contact, showed the best results. When comparing the studies reviewed in all the review papers, a moderate overlap was noted. However, when comparing individual reviews with each other, they showed a high overlap of the included studies. CONCLUSIONS: Mixed delivery methods and intervention content showed the most effective results in supporting those caring for people with dementia. However, many papers do not separate the results for differing intervention contents or delivery; this needs to be considered when drawing conclusions. There was an overlap among the studies included in the reviews. This suggests a lack of current research on the effectiveness of web-based interventions for people caring for a person with dementia. There was also a lack of consistency in the outcome measures across all papers. Future studies can involve updating research on the effectiveness of these interventions while distinguishing between different intervention types, thus creating guidelines for the use of standardized measures to enable comparisons of intervention effects and improve the scientific quality of the overall research. TRIAL REGISTRATION: PROSPERO CRD42021241559; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=241559.


Subject(s)
Dementia , Internet-Based Intervention , Telemedicine , Caregivers/psychology , Dementia/psychology , Dementia/therapy , Humans , Systematic Reviews as Topic
10.
Anal Biochem ; 623: 114205, 2021 06 15.
Article in English | MEDLINE | ID: mdl-33891963

ABSTRACT

Protein glycosylation contributes to critical biological function of glycoproteins. Glycan analysis is essential for the production of biopharmaceuticals as well as for the identification of disease biomarkers. However, glycans are highly heterogeneous, which has considerably hampered the progress of glycomics. Here, we present an improved 96-well plate format platform for streamlined glycan profiling that takes advantage of rapid glycoprotein denaturation, deglycosylation, fluorescent derivatization, and on-matrix glycan clean-up. This approach offers high sensitivity with consistent identification and quantification of diverse N-glycans across multiple samples on a high-throughput scale. We demonstrate its capability for N-glycan profiling of glycoproteins from various sources, including two recombinant monoclonal antibodies produced from Chinese Hamster Ovary cells, EG2-hFc and rituximab, polyclonal antibodies purified from human serum, and total glycoproteins from human serum. Combined with the complementary information obtained by sequential digestion from exoglycosidase arrays, this approach allows the detection and identification of multiple N-glycans in these complex biological samples. The reagents, workflow, and Hydrophilic interaction liquid chromatography with fluorescence detection (HILIC-FLD), are simple enough to be implemented into a straightforward user-friendly setup. This improved technology provides a powerful tool in support of rapid advancement of glycan analysis for biopharmaceutical development and biomarker discovery for clinical disease diagnosis.


Subject(s)
Biological Products/analysis , Biological Products/chemistry , High-Throughput Screening Assays/methods , Polysaccharides/analysis , Polysaccharides/chemistry , Animals , Antibodies, Monoclonal/analysis , Antibodies, Monoclonal/chemistry , Biomarkers/analysis , Biomarkers/chemistry , CHO Cells , Camelids, New World , Cricetulus , Drug Discovery/methods , Enzyme Assays/methods , Glycomics/methods , Glycoproteins/analysis , Glycoproteins/chemistry , Glycoside Hydrolases/chemistry , Humans , Hydrophobic and Hydrophilic Interactions , Polysaccharides/blood , Recombinant Proteins/analysis , Recombinant Proteins/chemistry , Spectrometry, Fluorescence/methods
12.
Nat Commun ; 11(1): 4451, 2020 09 15.
Article in English | MEDLINE | ID: mdl-32934202

ABSTRACT

Large brains and behavioural innovation are positively correlated, species-specific traits, associated with the behavioural flexibility animals need for adapting to seasonal and unpredictable habitats. Similar ecological challenges would have been important drivers throughout human evolution. However, studies examining the influence of environmental variability on within-species behavioural diversity are lacking despite the critical assumption that population diversification precedes genetic divergence and speciation. Here, using a dataset of 144 wild chimpanzee (Pan troglodytes) communities, we show that chimpanzees exhibit greater behavioural diversity in environments with more variability - in both recent and historical timescales. Notably, distance from Pleistocene forest refugia is associated with the presence of a larger number of behavioural traits, including both tool and non-tool use behaviours. Since more than half of the behaviours investigated are also likely to be cultural, we suggest that environmental variability was a critical evolutionary force promoting the behavioural, as well as cultural diversification of great apes.


Subject(s)
Behavior, Animal , Pan troglodytes/psychology , Animals , Ecosystem , Environment , Female , Forests , Male , Pan troglodytes/physiology , Tool Use Behavior
13.
Science ; 363(6434): 1453-1455, 2019 Mar 29.
Article in English | MEDLINE | ID: mdl-30846610

ABSTRACT

Chimpanzees possess a large number of behavioral and cultural traits among nonhuman species. The "disturbance hypothesis" predicts that human impact depletes resources and disrupts social learning processes necessary for behavioral and cultural transmission. We used a dataset of 144 chimpanzee communities, with information on 31 behaviors, to show that chimpanzees inhabiting areas with high human impact have a mean probability of occurrence reduced by 88%, across all behaviors, compared to low-impact areas. This behavioral diversity loss was evident irrespective of the grouping or categorization of behaviors. Therefore, human impact may not only be associated with the loss of populations and genetic diversity, but also affects how animals behave. Our results support the view that "culturally significant units" should be integrated into wildlife conservation.


Subject(s)
Conservation of Natural Resources/methods , Pan troglodytes/psychology , Social Behavior , Animals , Datasets as Topic , Humans
14.
Ecol Evol ; 9(3): 1489-1500, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30805176

ABSTRACT

Ecological niche models (ENMs) are often used to predict species distribution patterns from datasets that describe abiotic and biotic factors at coarse spatial scales. Ground-truthing ENMs provide important information about how these factors relate to species-specific requirements at a scale that is biologically relevant for the species. Chimpanzees are territorial and have a predominantly frugivorous diet. The spatial and temporal variation in fruit availability for different chimpanzee populations is thus crucial, but rarely depicted in ENMs. The genetic and geographic distinction within Nigeria-Cameroon chimpanzee (Pan troglodytes ellioti) populations represents a unique opportunity to understand fine scale species-relevant ecological variation in relation to ENMs. In Cameroon, P. t. ellioti is composed of two genetically distinct populations that occupy different niches: rainforests in western Cameroon and forest-woodland-savanna mosaic (ecotone) in central Cameroon. We investigated habitat variation at three representative sites using chimpanzee-relevant environmental variables, including fruit availability, to assess how these variables distinguish these niches from one another. Contrary to the assumption of most ENM studies that intact forest is essential for the survival of chimpanzees, we hypothesized that the ecotone and human-modified habitats in Cameroon have sufficient resources to sustain large chimpanzee populations. Rainfall, and the diversity, density, and size of trees were higher at the rainforest. The ecotone had a higher density of terrestrial herbs and lianas. Fruit availability was higher at Ganga (ecotone) than at Bekob and Njuma. Seasonal variation in fruit availability was highest at Ganga, and periods of fruit scarcity were longer than at the rainforest sites. Introduced and secondary forest species linked with anthropogenic modification were common at Bekob, which reduced seasonality in fruit availability. Our findings highlight the value of incorporating fine scale species-relevant ecological data to create more realistic models, which have implications for local conservation planning efforts.

16.
BMC Evol Biol ; 15: 2, 2015 Jan 21.
Article in English | MEDLINE | ID: mdl-25608567

ABSTRACT

BACKGROUND: The Nigeria-Cameroon chimpanzee (Pan troglodytes ellioti) is found in the Gulf of Guinea biodiversity hotspot located in western equatorial Africa. This subspecies is threatened by habitat fragmentation due to logging and agricultural development, hunting for the bushmeat trade, and possibly climate change. Although P. t. ellioti appears to be geographically separated from the neighboring central chimpanzee (P. t. troglodytes) by the Sanaga River, recent population genetics studies of chimpanzees from across this region suggest that additional factors may also be important in their separation. The main aims of this study were: 1) to model the distribution of suitable habitat for P. t. ellioti across Cameroon and Nigeria, and P. t. troglodytes in southern Cameroon, 2) to determine which environmental factors best predict their optimal habitats, and 3) to compare modeled niches and test for their levels of divergence from one another. A final aim of this study was to examine the ways that climate change might impact suitable chimpanzee habitat across the region under various scenarios. RESULTS: Ecological niche models (ENMs) were created using the software package Maxent for the three populations of chimpanzees that have been inferred to exist in Cameroon and eastern Nigeria: (i) P. t. troglodytes in southern Cameroon, (ii) P. t. ellioti in northwestern Cameroon, and (iii) P. t. ellioti in central Cameroon. ENMs for each population were compared using the niche comparison test in ENMtools, which revealed complete niche divergence with very little geographic overlap of suitable habitat between populations. CONCLUSIONS: These findings suggest that a positive relationship may exist between environmental variation and the partitioning of genetic variation found in chimpanzees across this region. ENMs for each population were also projected under three different climate change scenarios for years 2020, 2050, and 2080. Suitable habitat of P. t. ellioti in northwest Cameroon / eastern Nigeria is expected to remain largely unchanged through 2080 in all considered scenarios. In contrast, P. t. ellioti in central Cameroon, which represents half of the population of this subspecies, is expected to experience drastic reductions in its ecotone habitat over the coming century.


Subject(s)
Climate Change , Ecosystem , Pan troglodytes/classification , Pan troglodytes/genetics , Animals , Cameroon , Genetic Variation , Genetics, Population , Nigeria
17.
BMC Evol Biol ; 15: 3, 2015 Jan 21.
Article in English | MEDLINE | ID: mdl-25608610

ABSTRACT

BACKGROUND: Chimpanzees (Pan troglodytes) can be divided into four subspecies. Substantial phylogenetic evidence suggests that these subspecies can be grouped into two distinct lineages: a western African group that includes P. t. verus and P. t. ellioti and a central/eastern African group that includes P. t. troglodytes and P. t. schweinfurthii. The geographic division of these two lineages occurs in Cameroon, where the rages of P. t. ellioti and P. t. troglodytes appear to converge at the Sanaga River. Remarkably, few population genetic studies have included wild chimpanzees from this region. RESULTS: We analyzed microsatellite genotypes of 187 wild, unrelated chimpanzees, and mitochondrial control region sequencing data from 604 chimpanzees. We found that chimpanzees in Cameroon and eastern Nigeria comprise at least two, and likely three populations. Both the mtDNA and microsatellite data suggest that there is a primary separation of P. t. troglodytes in southern Cameroon from P. t. ellioti north and west of the Sanaga River. These two populations split ~200-250 thousand years ago (kya), but have exchanged one migrant per generation since separating. In addition, P. t. ellioti consists of two populations that split from one another ~4 kya. One population is located in the rainforests of western Cameroon and eastern Nigeria, whereas the second population appears to be confined to a savannah-woodland mosaic in central Cameroon. CONCLUSIONS: Our findings suggest that there are as many as three genetically distinct populations of chimpanzees in Cameroon and eastern Nigeria. P. t. troglodytes in southern Cameroon comprises one population that is separated from two populations of P. t. ellioti in western and central Cameroon, respectively. P. t. ellioti and P. t. troglodytes appear to be characterized by a pattern of isolation-with-migration, and thus, we propose that neutral processes alone can not explain the differentiation of P. t. ellioti and P. t. troglodytes.


Subject(s)
Biological Evolution , Pan troglodytes/classification , Pan troglodytes/genetics , Animals , Cameroon , DNA, Mitochondrial/genetics , Genetics, Population , Microsatellite Repeats , Nigeria , Phylogeny
18.
Iowa Orthop J ; 34: 118-22, 2014.
Article in English | MEDLINE | ID: mdl-25328470

ABSTRACT

INTRODUCTION: Distal radial fractures are one of the most common orthopaedic injuries. An effective treatment strategy is needed to ensure good outcome and better resource usage. AIM: To identify the significance of the number of instability markers in distal radial fractures in predicting outcome and proposing a standardized management strategy. METHODS: Data was collected retrospectively over three months at the Northern General Hospital, Sheffield. All patients who had a distal radius fracture in the defined time period and matched our criteria were included. Relevant instability markers identified through a literature review were: age >60 years, dorsal angulation >20°, intra-articular fracture, ulna fracture, dorsal comminution, radial shortening and osteoporosis. The number of instability markers, management and outcome were recorded for each patient. The strategy of management was subdivided into: plaster cast immobilisation with subsequent rehabilitation, manipulation with subsequent cast immobilization and surgery (locked volar plating). Outcomes were graded as "good" or "poor" based on the complications and the function achieved at discharge from follow-up. RESULTS: Two hundred and seven patients were included in our study. One hundred and nineteen patients had <3 instability markers (Group A) and 88 had >4 (Group B). One hundred and sixty-two were female and 45 were male. The average age was 60 years and the age range was 19 to 96 years. In Group A, 91% achieved "good" outcome regardless of management strategy, versus 66% in Group B (p<0.001). In Group B, amongst patients who had surgery (29), 79% achieved "good" outcome, however those with manipulation alone (38), only 58% achieved "good" outcome (p > 0.03 (one tailed), p > 0.06 (double tailed)). CONCLUSIONS: We have found that four or more instability markers are globally associated with a poorer outcome. Patients with four or more markers who underwent surgery did uniformly better than those with manipulation alone. However, in patients with three or fewer markers, non-operative management yielded equally good outcomes. We plan to use this as a pilot study for future primary research.


Subject(s)
Fracture Fixation, Internal/methods , Fracture Healing , Radius Fractures/surgery , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Pilot Projects , Prognosis , Range of Motion, Articular , Retrospective Studies , Treatment Outcome , Young Adult
19.
PLoS One ; 8(3): e59469, 2013.
Article in English | MEDLINE | ID: mdl-23469289

ABSTRACT

African forest elephants- taxonomically and functionally unique-are being poached at accelerating rates, but we lack range-wide information on the repercussions. Analysis of the largest survey dataset ever assembled for forest elephants (80 foot-surveys; covering 13,000 km; 91,600 person-days of fieldwork) revealed that population size declined by ca. 62% between 2002-2011, and the taxon lost 30% of its geographical range. The population is now less than 10% of its potential size, occupying less than 25% of its potential range. High human population density, hunting intensity, absence of law enforcement, poor governance, and proximity to expanding infrastructure are the strongest predictors of decline. To save the remaining African forest elephants, illegal poaching for ivory and encroachment into core elephant habitat must be stopped. In addition, the international demand for ivory, which fuels illegal trade, must be dramatically reduced.


Subject(s)
Conservation of Natural Resources , Crime/economics , Elephants/physiology , Africa, Central , Animals , Conservation of Natural Resources/trends , Crime/statistics & numerical data , Ecosystem , Humans , Population Density , Socioeconomic Factors , Trees
20.
Ecol Evol ; 2(3): 550-61, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22822434

ABSTRACT

It is difficult to predict how current climate change will affect wildlife species adapted to a tropical rainforest environment. Understanding how population dynamics fluctuated in such species throughout periods of past climatic change can provide insight into this issue. The drill (Mandrillus leucophaeus) is a large-bodied rainforest adapted mammal found in West Central Africa. In the middle of this endangered monkey's geographic range is Lake Barombi Mbo, which has a well-documented palynological record of environmental change that dates to the Late Pleistocene. We used a Bayesian coalescent-based framework to analyze 2,076 base pairs of mitochondrial DNA across wild drill populations to infer past changes in female effective population size since the Late Pleistocene. Our results suggest that the drill underwent a nearly 15-fold demographic collapse in female effective population size that was most prominent during the Mid Holocene (approximately 3-5 Ka). This time period coincides with a period of increased dryness and seasonality across Africa and a dramatic reduction in forest coverage at Lake Barombi Mbo. We believe that these changes in climate and forest coverage were the driving forces behind the drill population decline. Furthermore, the warm temperatures and increased aridity of the Mid Holocene are potentially analogous to current and future conditions faced by many tropical rainforest communities. In order to prevent future declines in population size in rainforest-adapted species such as the drill, large tracts of forest should be protected to both preserve habitat and prevent forest loss through aridification.

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