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Genetic Research on Cardiac Channelopathies in African and African-Descent Populations: A Scoping Review.

Cardiac channelopathies are inherited arrhythmias that can lead to sudden cardiac death. Despite Africa's extensive genomic diversity, African and African-descent populations remain underrepresented in genetic research, creating gaps in variant interpretation and clinical care. This scoping review aims to map the extent, range, and nature of genetic research on cardiac channelopathies in these populations and to identify key geographic, thematic, and methodological gaps. Using the Joanna Briggs Institute scoping review methodology and the Population-Concept-Context framework, systematic searches in PubMed, Embase, and Web of Science identified original human studies on cardiac channelopathies with genetic data. Extracted variables included study characteristics, populations, types of channelopathies, and reported genes and variants. Forty-four studies met the inclusion criteria. Most studies originated from the United States and South Africa, while West, Central, and East Africa were largely underrepresented. US Black individuals and South African individuals of continental African or African-descended ancestry (excluding populations of European descent such as Cape Afrikaner people) were the most studied groups, with other continental African groups rarely included. Long QT syndrome was the predominant focus, and SCN5A, KCNQ1, and KCNH2 were the most frequently analyzed genes. Many of the genetic variants discussed remained of uncertain significance due to limited functional validation and the underrepresentation of African genomes in reference databases. Genetic research on cardiac channelopathies in populations of African ancestry is limited, restricting variant interpretation, counseling, and risk prediction. Broader African inclusion, expanded gene screening, and functional studies are essential to improve diagnostics and promote equity in genomic medicine.

Humans

Genetic Basis of Pancreatic Steatosis: A Systematic Review of Comparison between African and Non-African Populations.

This systematic review compared genetic evidence of pancreatic steatosis across African and non-African populations to illuminate ancestry-specific mechanisms and precision-prevention opportunities. Following PRISMA guidelines for reporting, a search was conducted across PubMed, Scopus, Web of Science, and NHGRI-EBI GWAS Catalog for studies spanning 2011 to 31st March 2026. Eligible studies included genome-wide association studies (GWAS), polygenic risk score (PRS), and Mendelian randomization (MR) analyses that reported genetic associations with pancreatic fat phenotypes and had explicit ancestry stratification or comparison. Narrative thematic synthesis was performed due to methodological heterogeneity. Six core genetic studies (N > 120,000 participants) were included. The only multi-ethnic GWAS found a strong protective variant of African ancestry, rs73449607 (near PDX1/PLUTO), which reduced pancreatic fat (&#x3b2; = -0.67, P = 4.50 &#xd7; 10&#x207b;&#x2078;) and explained 14.3% of the variance in African Americans (versus 5.3% overall). UK Biobank race-stratified PRS analyses confirmed the lowest pancreatic fat fraction in Black participants, with the strongest HbA1c PRS-fat association in this group (&#x3c1; = 0.23, P < 0.0001). European-dominant GWAS highlighted risk loci, including FUT2 rs601338 (higher fat and chronic pancreatitis risk, OR 1.26). MR studies demonstrated causal links between genetically predicted intra-pancreatic fat deposition (IPFD) and pancreatic ductal adenocarcinoma (PDAC) (OR 2.46 per SD) but not diabetes. African-ancestry genomes confer substantial protection against pancreatic steatosis, whereas non-African genomes are enriched for risk alleles that amplify the non-alcoholic fatty pancreas disease (NAFPD)-to-PDAC cascade. These ancestry-differentiated mechanisms position NAFPD as a precision medicine target.

Africa

The African Cancer Leaders Institute: a decade of strategic development of the African next generation leaders in cancer care, research, education and advocacy.

Leadership and mentorship play an important role in supporting the career development of health professionals. In many African countries, supervision activities focus on technical and operational aspects rather than catalysing career and leadership development. Thus, mentorship and coaching interventions need to be implemented in African healthcare institutions as components of health systems strengthening strategies. Due to its holistic nature, cancer care involves interprofessional collaborations to develop and provide a problem-solving mindset. It is therefore an area that would benefit from leadership and mentorship, mainly in a limited-resources context. The identified benefits from leadership development in cancer care in Africa led to the creation of the African Cancer Leaders Institute (ACLI) of the African Organization for Research and Training in Cancer (AORTIC), consisting of mentors and trainees from Africa and the USA. ACLI trainees are selected through a competitive application process. During the ACLI biennial meetings, coinciding with the AORTIC conference, trainees, including early-stage/mid-career investigators, oncologists, nurses, advocates and other health professionals, meet to learn about best practices in cancer research, grant writing, scientific reporting, mentor relationships, academic pressures and professional-personal life balance. This paper describes the goals of the ACLI, its mission and achievements, the vision behind creating such important programmes and the benefits of its participants in leadership, coaching and mentorship in improving cancer care in Africa.

Humans

Anthropometric studies on African athletes who participated in the 1st African University Games.

1. Height, weight, skinfold thicknesses and mid-arm circumference were measured in 540 males and 117 females aged 20-24 years who took part in the 1st African University Games, held at the University of Ghana, Legon. Body fat content, Quetelet's index (weight divided by height X 100; Khosla & Lowe (1967)) and mid-arm muscle circumference were derived from the measurements taken. 2. The physique or body-build of the subjects as assessed by Quetelet's index showed that both male and female subjects from the various countries were of medium body-build. The body fat content for males was between 10 and 12% with the exception of the Egyptians (12.8%) while that of females was between 23-24%. 3. Body measurements of the subjects compared favourably with that of international standards (WHO, 1966) with the exception of the triceps skinfold thickness which was only approximately 60% of the standard value. 4. The low values for triceps skinfold thickness are probably due to differences in the distribution of subcutaneous fat at different sites in the body as found between caucasian and non-caucasian population groups. The results are discussed in relation to the findings of other workers on ethnic differences in skinfold thickness.

Adult

Diet and urinary steroids in black and white North American men and black South African men.

Urinary steroid hormone content was determined in Black and White North American men and in rural Black South African men between 40 and 55 years of age and in Black South African men over 60 years of age when maintained on their customary diets or when transferred to a vegetarian or Western diet, respectively. When eating their customary diets, Black South African men had lower levels of urinary estrogens and androgens than did Black and White North American men. The total androgen content decreased significantly in Black North American men on the vegetarian diet and increased in Black South African men fed a Western diet. Urinary excretion of estrogens was higher in older than in younger rural Black South African men. Data indicated that a vegetarian diet modified androgen and estrogen metabolism in North American men and that a Western diet was associated with higher levels of urinary steroid hormones in young Black South African men. Diet-related changes in steroid metabolism in rural Black South African men were age dependent. The relationship of the increased urinary excretion of steroid hormones in Black South African men, a low-risk group fed a Western diet, and the decreased excretion in Black and White North American men, high-risk groups fed a vegetarian diet, to the development of prostatic cancer remains to be clarified.

Adult

Influence of Ancestral and Geographic Factors on Intracerebral Hemorrhage Risks Among Africans and Americans.

BACKGROUND: We investigated whether risk factors for intracerebral hemorrhage (ICH) among indigenous Africans (IA) would vary in prevalence and effect compared with self-reported African, Hispanic, and White Americans by comparing data from 2 independent population-based case-control studies conducted in West Africa and the United States. METHODS: We compared ICH risk factors common to the SIREN (Stroke Investigative Research and Educational Network: 1100 case-control pairs) and the ERICH (Ethnic/Racial Variation of Intracerebral Hemorrhage: 999 case-control pairs African American participants, 998 case-control pairs, Hispanic Americans, 1000 case-control pairs, White Americans) studies. Ethnicity/Race was self-reported. The effect measure of interest is the odds ratio (OR). To test for differences in the effects of the risk factors between the SIREN IA study population and each of the ERICH study populations, a test for heterogeneity was computed using the R program, metagen (version 4.9-6). RESULTS: ICH occurred at a younger age among IA (54.3&#xb1;13.4 years), African Americans (58.0&#xb1;12.7), and Hispanic Americans (58.9&#xb1;14.3), compared with White Americans (69.1&#xb1;13.9). The largest distinction was for hypertension, where IA exhibited a much larger risk of ICH than the American study population (OR, 67.02 [95% CI, 33.30-134.85]), African American (OR, 3.71 [95% CI, 2.53-5.44]); Hispanic (OR, 3.55 [95% CI, 2.54-4.92]), and White population (OR, 2.69 [95% CI, 1.95-3.69]). Current alcohol use exhibited increased risk in IA (OR, 2.24 [95% CI, 1.36-3.67]), but not in African Americans (OR, 0.63 [95% CI, 0.46-0.86]), Hispanic (OR, 0.87 [95% CI, 0.65-1.17]), and White Americans (OR, 0.51 [95% CI, 0.38-0.69]). CONCLUSIONS: Identical or comparable risk factors do not consistently result in the same disease risk across different cultures and regions. Therefore, to improve our understanding of the genetic determinants and biological pathways driving ICH risk, it is crucial to study multiple populations, including IA, while accounting for the influence of environmental and social factors.

Adult

Characterisation of HIV-1 Gag Cytotoxic T-Lymphocyte Epitopes in the Southern African Region-A Systematic Review.

During early HIV-1 infection, robust Cytotoxic T-lymphocyte (CTL) responses are mostly targeted at immunodominant Gag p24 epitopes to reduce HIV-1 viraemia to a set-point. The aim of this study was to review the current body of knowledge on HIV-1 Gag CTL epitopes in the southern African region where subtype C is prevalent. Peer-reviewed records were obtained from three databases: PubMed Central, Web of Science Core Collection, and Scopus, using the following search terms: HIV subtype C Gag epitopes, and HIV clade C Gag epitopes. The search results were restricted to countries within the southern African region, and only data published in English and between the years 2000-2025 were considered for this review. The search from the three databases produced a total of 2103 peer-reviewed records, and 49 records were included in the review. The majority of studies (58.44%) were conducted in South Africa, followed by Botswana (15.58%), Zambia (10.39%), Malawi (7.79%), Zimbabwe (6.49%) and Angola (1.30%). There were no studies identified from other southern African countries. A total of 60 Gag CTL epitopes were identified, of which 17 (28.33%) were located within the matrix protein (p17), 33 (55.00%) within the capsid protein (p24), and 4 (6.67%) within the Gag polyprotein (p2p7p1p6). The commonly detected immunodominant epitopes were mostly located within the Gag p24 protein; and included TPQDLNTML (TL9, Gag p24 48-56) and TSTLQEQIGW (TW10, Gag p24 108-117) present at 16.00% and 13.3%, respectively. The proportion of HLA-A, B and C allotypes in this systematic review were 18%, 78%, and 4%, respectively. The more common HLA-B allotypes that restrict immunodominant Gag epitopes and facilitate better control of HIV-1 were HLA-B*57, -B*58:01, -B*42:01 and -B*81:01. This systematic review has provided important insights into the description of immunodominant Gag epitopes and HLA-I alleles that contribute to the control of HIV-1 viraemia in the southern African region. It has also exposed that some CTL epitopes identified in the southern African studies are not reported on the Los Alamos HIV database (LANL HIV database). This highlights a need to have this database updated with this information as it is used as a reference for epitopes. This review could provide insights into the design of an epitope-based HIV-1 vaccine that would also be effective in the southern African region.

Humans

Low and differential polygenic score generalizability among African populations due largely to genetic diversity.

African populations are vastly underrepresented in genetic studies but have the most genetic variation and face wide-ranging environmental exposures globally. Because systematic evaluations of genetic prediction had not yet been conducted in ancestries that span African diversity, we calculated polygenic risk scores (PRSs) in simulations across Africa and in empirical data from South Africa, Uganda, and the United Kingdom to better understand the generalizability of genetic studies. PRS accuracy improves with ancestry-matched discovery cohorts more than from ancestry-mismatched studies. Within ancestrally and ethnically diverse South African individuals, we find that PRS accuracy is low for all traits but varies across groups. Differences in African ancestries contribute more to variability in PRS accuracy than other large cohort differences considered between individuals in the United Kingdom versus Uganda. We computed PRS in African ancestry populations using existing European-only versus ancestrally diverse genetic studies; the increased diversity produced the largest accuracy gains for hemoglobin concentration and white blood cell count, reflecting large-effect ancestry-enriched variants in genes known to influence sickle cell anemia and the allergic response, respectively. Differences in PRS accuracy across African&#xa0;ancestries originating from diverse regions are as large as across out-of-Africa continental ancestries, requiring commensurate nuance.

Humans

Stroke in the Africans.

Stroke is increasingly becoming a major cause of death and morbidity in African population among most of which the frequencies of hypertension are considerable, although hard data based on community surveys are lacking and most of the information available is from hospital data. The epidemiology of stroke in the Africans is reviewed. The frequencies in hospital populations varied from 0.9% to 4.0% and stroke accounted for 0.5% to 45% of neurological admissions. There is male predominance in published series. The main risk factors are hypertension, diabetes mellitus and homozygous sickle cell disease (in children only). Ischaemic stroke is by far the commonest clinical type encountered. These conclusions are further supported by experience at Ibadan, of over 1100 Africans seen over 18 years reported briefly in this communication. The results of the first community study over a 2-year period on the incidence of stroke in an African Urban (Ibadan) Community are presented. The study was carried out as part of a multinational multicentric study initiated and sponsored by the World Health Organization. The male to female ratio was five to two. Incidence rates reached peaks in the eighth decade in males and in seventh decade in females and were higher in males in all age groups, and the rates are comparable with those recorded in European populations, except in those under the age of 40 in Ibadan, in which age-specific incidence rates are considerably lower than in European and Japanese populations. Hypertension, diabetes mellitus constituted the main risk factors. Mortality and recurrence rates are described and are similar to experience in the Caucasians. Hypertension in the Nigerians predispose to a high frequency of cerebrovascular disease other than through mainly cerebral atherosclerosis. With increasing longevity of Nigerians and other Africans, the mortality and morbidity caused by cerebrovascular disease would probably become of enormous dimensions and adequate control of high blood pressure on a community basis may be the only way of preventing this: this would be desirable as myocardial infarction in contradistinction to hypertensive heart disease is an uncommon complication of high blood pressure in the Africans and prevention of hypertensive heart disease as shown by experience elsewhere can be achieved by control of high blood pressure, which does not seem to prevent ischaemic myocardial disease.

Adolescent

Metabolomic profiling of glucose homeostasis in African Americans: the Insulin Resistance Atherosclerosis Family Study (IRAS-FS).

INTRODUCTION: African Americans are at increased risk for type 2 diabetes. OBJECTIVES: This work aimed to examine metabolomic signature of glucose homeostasis in African Americans. METHODS: We used an untargeted liquid chromatography-mass spectrometry metabolomic approach to comprehensively profile 727 plasma metabolites among 571 African Americans from the Insulin Resistance Atherosclerosis Family Study (IRAS-FS) and investigate the associations between these metabolites and both the dynamic (SI, insulin sensitivity; AIR, acute insulin response; DI, disposition index; and SG, glucose effectiveness) and basal (HOMA-IR and HOMA-B) measures of glucose homeostasis using univariate and regularized regression models. We also compared the results with our previous findings in the IRAS-FS Mexican Americans. RESULTS: We confirmed increased plasma metabolite levels of branched-chain amino acids and their metabolic derivatives, 2-aminoadipate, 2-hydroxybutyrate, glutamate, arginine and its metabolic derivatives, carbohydrate metabolites, and medium- and long-chain fatty acids were associated with insulin resistance, while increased plasma metabolite levels in the glycine, serine and threonine metabolic pathway were associated with insulin sensitivity. We also observed a differential ancestral effect of glutamate on glucose homeostasis with significantly stronger effects observed in African Americans than those previously observed in Mexican Americans. CONCLUSION: We extended the observations that metabolites are useful biomarkers in the identification of prediabetes in individuals at risk of type 2 diabetes in African Americans. We revealed, for the first time, differential ancestral effect of certain metabolites (i.e., glutamate) on glucose homeostasis traits. Our study highlights the need for additional comprehensive metabolomic studies in well-characterized multiethnic cohorts.

Humans

Genetic analysis in African ancestry populations reveals genetic contributors to lung cancer susceptibility.

Striking disparities in lung cancer exist, with Black/African American individuals disproportionately affected by lung cancer, yet the genetic architecture in African ancestry individuals is poorly understood. We aimed to address this by performing a comprehensive genetic association study of lung cancer, incorporating local ancestry, across 6,490 African ancestry individuals (2,390 individuals with lung cancer and 4,100 control subjects). We identified a single genome-wide significant (p < 5 &#xd7; 10-8) locus, 15q25.1 (lead SNP rs17486278, OR [95% CI] = 1.34 [1.23-1.45], p = 4.52 &#xd7; 10-12), that has consistently shown a strong association with lung cancer across populations. Additionally, we identified nine suggestive (p < 1 &#xd7; 10-6) loci. Four of these loci (3p12.1, 8q22.2, 14q11.2, and 18q22.3) have no prior reported associations with lung cancer. We performed a multi-ancestry lung cancer meta-analysis using prior large-scale summary statistics from European and Asian ancestry populations, incorporating our African ancestry results. The meta-analysis identified 17 genome-wide significant loci, including an association with locus 4q35.2 (p = 1.22 &#xd7; 10-8), a genomic region that has been previously linked to forced expiratory volume. Genome-wide SNP-based heritability for lung cancer was 16% among African ancestry individuals. Follow-up in silico functional analyses identified genetically regulated gene expression (GReX) of nine genes (AC012184.3, ADK, CCDC12, CHRNA3, EML4, PSMA4, SNRNP200, TMEM50A, and ZYG11A) associated with lung cancer risk and biological pathways relevant to cancer and lung function. Cumulatively, these findings further elucidate the genetic architecture of lung cancer in African ancestry individuals, confirming prior loci and revealing new loci.

Female

Fine-mapping the CYP2A6 regional association with nicotine metabolism among African American smokers.

The nicotine metabolite ratio (NMR; 3'hydroxycotinine/cotinine) is a stable biomarker for CYP2A6 enzyme activity and nicotine clearance, with demonstrated clinical utility in personalizing smoking cessation treatment. Common genetic variation in the CYP2A6 region is strongly associated with NMR in smokers. Here, we investigated this regional association in more detail. We evaluated the association of CYP2A6 single-nucleotide polymorphisms (SNPs) and * alleles with NMR among African American smokers (N&#x2009;=&#x2009;953) from two clinical trials of smoking cessation. Stepwise conditional analysis and Bayesian fine-mapping were undertaken. Putative causal variants were incorporated into an existing African ancestry-specific genetic risk score (GRS) for NMR, and the performance of the updated GRS was evaluated in both African American (n&#x2009;=&#x2009;953) and European ancestry smokers (n&#x2009;=&#x2009;933) from these clinical trials. Five independent associations with NMR in the CYP2A6 region were identified using stepwise conditional analysis, including the deletion variant CYP2A6*4 (beta&#x2009;=&#x2009;-0.90, p&#x2009;=&#x2009;1.55&#x2009;&#xd7;&#x2009;10-11). Six putative causal variants were identified using Bayesian fine-mapping (posterior probability, PP&#x2009;=&#x2009;0.67), with the top causal configuration including CYP2A6*4, rs116670633, CYP2A6*9, rs28399451, rs8192720, and rs10853742 (PP&#x2009;=&#x2009;0.09). Incorporating these putative causal variants into an existing ancestry-specific GRS resulted in comparable prediction of NMR within African American smokers, and improved trans-ancestry portability of the GRS to European smokers. Our findings suggest that both * alleles and SNPs underlie the association of the CYP2A6 region with NMR among African American smokers, identify a shortlist of variants that may causally influence nicotine clearance, and suggest that portability of GRSs across populations can be improved through inclusion of putative causal variants.

Adult

Long-read Sequences Mapped to a Complete Reference Genome Uncover Uncaptured Structural Variants across the Beta-globin Cluster in Africans with Sickle Cell Disease.

African genomes are marked by extensive complexity in the number and distribution of variants, yet remain under-represented in genetic databases and the human reference genome. This gap in representation limits the broad application of genomic medicine. Sickle cell disease (SCD) - one of the most common monogenic diseases - has its highest prevalence in Africa, and variation in disease severity has consistently been linked to the beta-globin locus, including levels of fetal hemoglobin (HbF). Modulation of HbF is central to current SCD gene therapies; however, the inherent complexity and variation at the locus in African genomes presents a challenge to translating these advances to Africa. Here, we align long-read single molecule sequences (LRS) targeted to the beta-globin region to the hg38 and T2T-CHM13v2 genome references in 40 individuals with SCD, predominantly recruited from three African countries. We demonstrate that the expanded T2T-CHM13v2 reference sequence at this locus reduces Structural Variant (SV) calls by 70% and uncovers uncaptured single nucleotide variants (SNVs). Across the cluster we report 343 SVs and 196 SNVs that have not been previously reported, including in LRS data from the All of Us project. By including African populations from ethnolinguistic groups that have not been previously surveyed we improve variant resolution and bolster evidence for observed variation. Finally, we identify a common &#x223c;4kb insertion locus overlapping the HBB promoter among individuals with high HbF. These results demonstrate the utility of combining a comprehensive reference genome with LRS in African populations to uncover genomic variation at disease-associated loci.

SNV

Arthrography of the shoulder in anterior dislocation: a study of African and Asian patients.

Arthrography of the shoulder was performed in 16 consecutive cases of primary anterior dislocation and in 11 cases of recurrent dislocation. All the primary dislocations were in African Negro patients and showed an unusually high incidence of capsular rupture rather than labral detachment. It is suggested that this is due to stronger soft tissue attachment to bone in Africans, resulting in fewer labral detachments and thus accounting for the low incidence of recurrent dislocation in the African populace. The series of recurrent dislocations, consisting of African and Asian patients, confirmed the low incidence in Africans but demonstrated labral detachment and humeral head defects common to both racial groups.

Adolescent

A comparison of HLA data of the North American black with African black and North American caucasoid populations.

For purposes of genetic comparison, the available HLA data on United States and African Black, together with United States Caucasoid populations, are summarized. Antigen frequencies and pairwise linkage disequilibria are presented for the HLA-A, -B and -C loci in Black populations typed for the 1975 Histocompatibility Testing Workshop. The Black population samples comprise 356 North American Blacks and 411 African Blacks of whom 222 were Bantu. These are compared with a sample of 503 American Caucasoids. All significant linkage disequilibria between the A and B loci found in North American Blacks were also present in the North American Caucasoids. Between the B and C loci, Bw35 and Cw4 were in strong linkage disequilibrium in all groups. Significantly stron association between the A and C loci (Aw28 with Cw3) were observed only in the African Blacks. There were unique disequilibria both in the American Caucasoids and African Blacks. Although the frequencies of many antigens in U.S. Blacks lie between those in Africans and U.S. Caucasoids, there are exceptions such as Aw33, Bw35, Cw4.

Africa

A comparison of the haematological values of cord bloods of African, European and Asian neonates.

A comparative study of the haematological values of 162 African and forty-one Asian and European cord bloods was conducted in Lusaka, Zambia, to determine whether neutropenia found in the majority of healthy African adults was present at birth. No significant differences in the total W.B.C., neutrophil and lymphocyte values of the three racial groups were found, from which it is concluded that Africans are not born with neutropenia. A review of previous studies, shows that as Africans changed from native to European type of diets, the incidence of neutropenia fell remarkably (in one community, from 88% to 27%), and no other environmental factors like hot climate or occult infections had such an effect. Absence of neutropenia in Africans at birth thus strengthens the case that this development in later life is acquired.

Asia

Clinico-pathological features of the nephrotic syndrome in South African children.

One hundred and thirty children of whom 74 were Africans and 56 Indians with contrasting clinicopathological patterns of the nephrotic syndrome are described. Eighty-six per cent of African children had obvious structural glomerular lesions which were associated with unresponsiveness to steroids while 75 per cent of Indians had minimal change nephrotic syndrome which was steroid responsive. The treatment history of a further 41 unbiopsied children with nephrotic syndrome (nine Africans, 32 Indians) support and emphasize this difference. Extramembranous and a tropical variety of extramembranous (36.5 per cent) together with proliferative (20.2 per cent) lesions accounted for most of the histological types in African children. The disease in Indian children was similar to that in other countries in age of onset, sex distribution, frequency of histological types and steroid responsiveness although there was a preponderance of frequent relapsers (69 per cent). Africans differed from children in other continents in the frequency of histological categories (therefore in steroid responsiveness) and occasionally in clinical behaviour. They also differed from children in tropical Africa in a lower incidence of the disease, male dominance and absence of malarial nephropathy. The aetiology of nephrotic syndrome in nearly all the children remains unidentified.

Adolescent