RESUMEN
The complete genome sequences of two poorly studied Prunus-infecting nepoviruses, apricot latent ringspot virus (ALRSV) and myrobalan latent ringspot virus (MLRSV) were determined, confirming that they are members of subgroup C. Serological, biological, and molecular data, in particular a low level (58.8%) of amino acid sequence identity in the coat protein, suggest that ALRSV and MLRSV should be considered taxonomically distinct. In addition, data mining of public RNASeq data from wild and ornamental Prunus identified two contigs representing the nearly complete genome of a new subgroup A nepovirus from a smooth stone peach (Prunus mira) dataset (SRR8369794) from the Himalayas, for which the name "Prunus mira virus A" is proposed.
Asunto(s)
Genoma Viral , Nepovirus , Filogenia , Enfermedades de las Plantas , Prunus , Prunus/virología , Enfermedades de las Plantas/virología , Nepovirus/genética , Nepovirus/aislamiento & purificación , Nepovirus/clasificación , Secuenciación Completa del Genoma , ARN Viral/genéticaRESUMEN
BACKGROUND: Proprotein convertase subtilisin kexin type 9 (PCSK9) monoclonal antibodies (mAbs) reduce fasting and post fat load cholesterol in non-HDL and intermediate density lipoprotein (IDL) in familial dysbetalipoproteinemia (FD). However, the effect of PCSK9 mAbs on the distribution and composition of atherogenic lipoproteins in patients with FD is unknown. OBJECTIVE: To evaluate the effect of the PCSK9 mAb evolocumab added to standard lipid-lowering therapy in patients with FD on fasting and post fat load lipoprotein distribution and composition. METHODS: Randomized placebo-controlled double-blind crossover trial comparing evolocumab (140 mg subcutaneous every 2 weeks) with placebo during two 12-week treatment periods. Patients received an oral fat load at the start and end of each treatment period. Apolipoproteins (apo) were measured with ultracentrifugation, gradient gel electrophoresis, retinyl palmitate and SDS-PAGE. RESULTS: PCSK9 mAbs significantly reduced particle number of all atherogenic lipoproteins, with a stronger effect on smaller lipoproteins than on larger lipoproteins (e.g. IDL-apoB 49%, 95%confidence interval (CI) 41-59 and very low-density lipoprotein (VLDL)-apoB 33%, 95%CI 16-50). Furthermore, PCSK9 mAbs lowered cholesterol more than triglyceride (TG) in VLDL, IDL and low-density lipoprotein (LDL) (e.g. VLDL-C 48%, 95%CI 29-63%; and VLDL-TG 20%, 95%CI 6.3-41%). PCSK9 mAbs did not affect the post fat load response of chylomicrons. CONCLUSION: PCSK9 mAbs added to standard lipid-lowering therapy in FD patients significantly reduced lipoprotein particle number, in particular the smaller and more cholesterol-rich lipoproteins (i.e. IDL and LDL). PCSK9 mAbs did not affect chylomicron metabolism. It seems likely that the observed effects are achieved by increased hepatic lipoprotein clearance, but the specific working mechanism of PCSK9 mAbs in FD patients remains to be elucidated.
Asunto(s)
Hiperlipoproteinemia Tipo III , Proproteína Convertasa 9 , Humanos , Proproteína Convertasa 9/metabolismo , Hiperlipoproteinemia Tipo III/tratamiento farmacológico , Lipoproteínas , Lipoproteínas VLDL , Colesterol , Anticuerpos Monoclonales/efectos adversos , Apolipoproteínas B , Lipoproteínas LDLRESUMEN
Clearance of triglyceride-rich lipoproteins (TRLs) is mediated by several receptors, including heparan sulfate proteoglycans (HSPGs). Sulfate glucosamine-6-O-endosulfatase-2 is a gene related to the regulation of HSPG. A variant in this gene, rs2281279, has been shown to be associated with triglycerides and insulin resistance. Objective: To determine the relationship between rs2281279, metabolic parameters and vascular events, and type 2 diabetes mellitus (T2DM) in patients at high cardiovascular risk and whether APOE genotype modifies this relationship. Methods: Patients (n = 4386) at high cardiovascular risk from the Utrecht Cardiovascular Cohort-Second Manifestations of Arterial Disease study were stratified according to their imputed rs2281279 genotype: AA (n = 2438), AG (n = 1642) and GG (n = 306). Effects of rs2281279 on metabolic parameters, vascular events and T2DM were analyzed with linear regression and Cox models. Results: There was no relationship between imputed rs2281279 genotype and triglycerides, non-high-density lipoprotein (HDL)-cholesterol, insulin and quantitative insulin sensitivity check index. During a median follow-up of 11.8 (IQR, 9.3-15.5) years, 1026 cardiovascular events and 320 limb events occurred. The presence of the G allele in rs2281279 did not affect the risk of vascular events [hazard ratio (HR), 1.03; 95% confidence interval (CI), 0.94-1.14] or limb events (HR, 0.92; 95% CI, 0.77-1.10). The presence of the G allele in rs2281279 did not affect the risk of T2DM (HR, 1.09; 95% CI, 0.94-1.27). The presence of the minor G allele of rs2281279 was associated with a beneficial risk profile in ε2ε2 patients, but not in ε3ε3 patients. Conclusions: Imputed rs2281279 genotype is not associated with metabolic parameters and does not increase the risk of vascular events or T2DM in patients at high risk for cardiovascular disease.
RESUMEN
BACKGROUND: Familial dysbetalipoproteinemia (FD) is the second most common monogenic lipid disorder (prevalence 1 in 850-3500), characterized by postprandial remnant accumulation and associated with increased cardiovascular disease (CVD) risk. Many FD patients do not achieve non-HDL-C treatment goals, indicating the need for additional lipid-lowering treatment options. OBJECTIVES: To evaluate the effect of the PCSK9 monoclonal antibody evolocumab added to standard lipid-lowering therapy on fasting and post fat load lipids and lipoproteins in patients with FD. METHODS: A randomized placebo-controlled double-blind crossover trial comparing evolocumab (140 mg subcutaneous every 2 weeks) with placebo during two 12-week treatment periods. At the start and end of each treatment period patients received an oral fat load. The primary endpoint was the 8-hour post fat load non-HDL-C area under the curve (AUC). Secondary endpoints included fasting and post fat load lipids and lipoproteins. RESULTS: In total, 28 patients completed the study. Mean age was 62±9 years and 93% had an Æ2Æ2 genotype. Evolocumab reduced the 8-hour post fat load non-HDL-C AUC with 49% (95%CI 42-55) and apolipoprotein B (apoB) AUC with 47% (95%CI 41-53). Other fasting and absolute post fat load lipids and lipoproteins including triglycerides and remnant-cholesterol were also significantly reduced by evolocumab. However, evolocumab did not have significant effects on the rise above fasting levels that occurred after consumption of the oral fat load. CONCLUSIONS: Evolocumab added to standard lipid-lowering therapy significantly reduced fasting and absolute post fat load concentrations of non-HDL-C, apoB and other atherogenic lipids and lipoproteins in FD patients. The clinically significant decrease in lipids and lipoproteins can be expected to translate into a reduction in CVD risk in these high-risk patients.
Asunto(s)
Anticolesterolemiantes , Enfermedades Cardiovasculares , Hiperlipoproteinemia Tipo III , Anciano , Humanos , Persona de Mediana Edad , Anticolesterolemiantes/uso terapéutico , Apolipoproteínas B , Enfermedades Cardiovasculares/tratamiento farmacológico , Ayuno , Hiperlipoproteinemia Tipo III/tratamiento farmacológico , Lipoproteínas , Proproteína Convertasa 9 , Resultado del Tratamiento , Metabolismo de los LípidosRESUMEN
AIM: To compare LDL-C concentrations using the Friedewald formula, the Martin-Hopkins formula, a direct assay and polyacrylamide gradient gel electrophoresis (PGGE) to the reference standard density gradient ultracentrifugation in patients with Familial Dysbetalipoproteinemia (FD) patients. We also compared non-HDL-cholesterol concentrations by two methods. METHODS: For this study data from 28 patients with genetically confirmed FD from the placebo arm of the EVOLVE-FD trial were used. Four different methods for determining LDL-C were compared with ultracentrifugation. Non-HDL-C was measured with standard assays and compared to ultracentrifugation. Correlation coefficients and Bland-Altman plots were used to compare the methods. RESULTS: Mean age of the 28 FD patients was 62 ± 9 years, 43 % were female and 93 % had an É2É2 genotype. LDL-C determined by Friedewald (R2 = 0.62, p <0.01), Martin-Hopkins (R2 = 0.50, p = 0.01) and the direct assay (R2 = 0.41, p = 0.03) correlated with density gradient ultracentrifugation. However, Bland-Altman plots showed considerable over- or underestimation by the four methods compared to ultracentrifugation. Non-HDL-C showed good correlation and agreement. CONCLUSION: In patients with FD, all four methods investigated over- or underestimated LDL-C concentrations compared with ultracentrifugation. In contrast, standard non-HDL-C assays performed well, emphasizing the use of non-HDL-C in patients with FD.
Asunto(s)
Hiperlipoproteinemia Tipo III , Humanos , Femenino , Persona de Mediana Edad , Anciano , Masculino , LDL-Colesterol , Hiperlipoproteinemia Tipo III/tratamiento farmacológico , Colesterol , Lipoproteínas , Triglicéridos , HDL-ColesterolRESUMEN
Chylomicronaemia accompanies hypertriglyceridaemia, usually due to a polygenic predisposition in combination with secondary risk factors. Monogenic chylomicronaemia represents a small subgroup of patients with hypertriglyceridaemia. This article describes three patients and illustrates the heterogeneity in the presentation of monogenic chylomicronaemia. The first case is a man with mild hypertriglyceridaemia who is a compound heterozygote for two variants in the LMF1 gene, without relevant medical history. The second case is a woman who is a double heterozygote of variants in the LPL and APOA5 genes. She experienced pancreatitis. The third case is a man, with recurrent pancreatitis attributed to severe hypertriglyceridaemia and homozygous for a variant in the APOC2 gene. This article highlights that in patients with hypertriglyceridaemia, the absence of pancreatitis or the presence of mild hypertriglyceridaemia does not exclude monogenic chylomicronaemia. Genetic screening should be considered in patients with unexplained or severe hypertriglyceridaemia, to determine appropriate treatment and follow-up.
Asunto(s)
Hipertrigliceridemia , Pancreatitis , Masculino , Femenino , Humanos , Hipertrigliceridemia/complicaciones , Hipertrigliceridemia/genética , Pancreatitis/etiología , Homocigoto , Pruebas Genéticas , GenotipoRESUMEN
BACKGROUND: Addressing sexual trauma in the context of HIV care is essential to improve clinical outcomes and mental health among women in South Africa. Women living with HIV (WLH) report disproportionately high levels of sexual trauma and have higher rates of posttraumatic stress disorder. Adherence to antiretroviral therapy (ART) may be difficult for traumatized women, as sexual trauma compounds the stress associated with managing HIV and is often comorbid with other mental health disorders, further compromising care engagement and adherence. ART initiation represents a unique window of opportunity for intervention to enhance motivation, increase care engagement, and address the negative effects of trauma on avoidant coping behaviors. Mental health interventions delivered by non-specialists in low- and middle-income countries have potential to treat depression, trauma, and effects of intimate partner violence among WLH. This study will examine the effectiveness of Improving AIDS Care after Trauma (ImpACT +), a task-shared, trauma-focused coping intervention, to promote viral suppression among WLH initiating ART in a South African clinic setting. METHODS: This study will be conducted in Khayelitsha, a peri-urban settlement situated near Cape Town, South Africa. Using a hybrid type 1 effectiveness-implementation design, we will randomize 350 WLH initiating ART to the ImpACT + experimental condition or the control condition (three weekly sessions of adapted problem-solving therapy) to examine the effectiveness of ImpACT + on viral suppression, ART adherence, and the degree to which mental health outcomes mediate intervention effects. ImpACT + participants will receive six once-a-week coping intervention sessions and six monthly maintenance sessions over the follow-up period. We will conduct mental health and bio-behavioral assessments at baseline, 4, 8, and 12 months, with care engagement data extracted from medical records. We will explore scalability using the Consolidated Framework for Implementation Research (CFIR). DISCUSSION: This trial is expected to yield important new information on psychologically informed intervention models that benefit the mental health and clinical outcomes of WLH with histories of sexual trauma. The proposed ImpACT + intervention, with its focus on building coping skills to address traumatic stress and engagement in HIV care and treatment, could have widespread impact on the health and wellbeing of individuals and communities in sub-Saharan Africa. TRIAL REGISTRATION: Clinicaltrials.gov NCT04793217 . Retrospectively registered on 11 March 2021.
Asunto(s)
Infecciones por VIH , Trastornos por Estrés Postraumático , Adaptación Psicológica , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Trauma Sexual , Sudáfrica , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/psicología , Trastornos por Estrés Postraumático/terapiaRESUMEN
Familial Dysbetalipoproteinemia (FD) is the second most common monogenic dyslipidemia and is associated with a very high cardiovascular risk due to cholesterol-enriched remnant lipoproteins. FD is usually caused by a recessively inherited variant in the APOE gene (ε2ε2), but variants with dominant inheritance have also been described. The typical dysbetalipoproteinemia phenotype has a delayed onset and requires a metabolic hit. Therefore, the diagnosis of FD should be made by demonstrating both the genotype and dysbetalipoproteinemia phenotype. Next Generation Sequencing is becoming more widely available and can reveal variants in the APOE gene for which the relation with FD is unknown or uncertain. In this article, two approaches are presented to ascertain the relationship of a new variant in the APOE gene with FD. The comprehensive approach consists of determining the pathogenicity of the variant and its causal relationship with FD by confirming a dysbetalipoproteinemia phenotype, and performing in vitro functional tests and, optionally, in vivo postprandial clearance studies. When this is not feasible, a second, pragmatic approach within reach of clinical practice can be followed for individual patients to make decisions on treatment, follow-up, and family counseling.
Asunto(s)
Apolipoproteínas E , Hiperlipoproteinemia Tipo III , Apolipoproteínas E/genética , Genotipo , Humanos , Hiperlipoproteinemia Tipo III/diagnóstico , Hiperlipoproteinemia Tipo III/genética , Hiperlipoproteinemia Tipo III/metabolismo , FenotipoRESUMEN
Carrot virome analysis using high-throughput sequencing revealed the presence of two RNA molecules with properties of satellite RNAs that are homologous to the satellite RNA of cereal yellow dwarf virus-RPV (CYDV-RPV). Satellite 1 is 298 nt long, while satellite 2 is 368 nt long. Their positive and negative genome strands contain hammerhead ribozymes similar to those found in other self-cleaving satellite RNAs. While both satellites were detected in Spanish carrot populations, only satellite 2 was found in French carrot populations. The most likely helper virus for these two satellites is carrot red leaf virus (CtRLV), which, like CYDV-RPV, is a polerovirus.
Asunto(s)
Daucus carota , Luteoviridae , ARN Catalítico , Secuencia de Bases , Luteoviridae/genética , ARN Catalítico/química , ARN Catalítico/genética , ARN Catalítico/metabolismo , Satélite de ARN/genética , ARN Viral/química , ARN Viral/genética , ViromaRESUMEN
Acute pancreatitis is an often-overlooked cause of acute abdominal pain in children and adolescents. Severe hypertriglyceridaemia is an important cause of recurrent acute pancreatitis. Monogenic causes of hypertriglyceridaemia, such as familial chylomicronaemia caused by lipoprotein lipase deficiency, are more frequently encountered in children and adolescents, but remain rare. Polygenic hypertriglyceridaemia is more common, but may require a precipitant before manifesting. With the global increase in obesity and type 2 diabetes, secondary causes of hypertriglyceridaemia in children and adolescents are increasing. We report two cases of severe hypertriglyceridaemia and pancreatitis in adolescent females. Hypertriglyceridaemia improved markedly with restriction of dietary fat. An inhibitor to lipoprotein lipase was found to be the cause in one patient, while in the other limited genetic investigation excluded chylomicronaemia owing to deficiency of lipoprotein lipase, its activators and processing proteins.
Asunto(s)
Diabetes Mellitus Tipo 2 , Hiperlipoproteinemia Tipo I , Hipertrigliceridemia , Pancreatitis , Enfermedad Aguda , Adolescente , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Humanos , Hiperlipoproteinemia Tipo I/complicaciones , Hiperlipoproteinemia Tipo I/diagnóstico , Hiperlipoproteinemia Tipo I/genética , Hipertrigliceridemia/complicaciones , Hipertrigliceridemia/genética , Lipoproteína Lipasa/genética , Pancreatitis/etiología , SudáfricaRESUMEN
PURPOSE OF REVIEW: Lipoprotein (a) [Lp(a)] is a highly atherogenic lipoprotein species. A unique feature of Lp(a) is the strong genetic determination of its concentration. The LPA gene is responsible for up to 90% of the variance in Lp(a), but other genes also have an impact. RECENT FINDINGS: Genome-wide associations studies indicate that the APOE gene, encoding apolipoprotein E (apoE), is the second most important locus modulating Lp(a) concentrations. Population studies clearly show that carriers of the apoE2 variant (ε2) display reduced Lp(a) levels, the lowest concentrations being observed in ε2/ε2 homozygotes. This genotype can lead predisposed adults to develop dysbetalipoproteinemia, a lipid disorder characterized by sharp elevations in cholesterol and triglycerides. However, dysbetalipoproteinemia does not significantly modulate circulating Lp(a). Mechanistically, apoE appears to impair the production but not the catabolism of Lp(a). These observations underline the complexity of Lp(a) metabolism and provide key insights into the pathways governing Lp(a) synthesis and secretion.
Asunto(s)
Hiperlipoproteinemia Tipo III , Lipoproteína(a) , Adulto , Apolipoproteínas E/genética , Genotipo , Humanos , Hiperlipoproteinemia Tipo III/genética , Lipoproteína(a)/genética , Lipoproteína(a)/metabolismo , Isoformas de Proteínas/genéticaRESUMEN
Abnormalities in the lipid profile are common, but it is often not easy to determine their cause. After exclusion of secondary causes, a primary (genetic) cause of dyslipidaemia should be considered. The most common monogenic dyslipidaemia is familial hypercholesterolemia (FH), but there are other clinically relevant genetic dyslipidaemias, including familial dysbetalipoproteinaemia (FD), monogenic chylomicronaemia and hypoalphalipoproteinemia. It is important to make a genetic diagnosis because it may influence the prognosis of the patient, for determining appropriate treatment goals and because it is relevant for family members. This clinical viewpoint explains the diagnostic process of genetic dyslipidaemias using two cases.
Asunto(s)
Dislipidemias , Hiperlipoproteinemia Tipo II , Humanos , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/genética , Hiperlipoproteinemia Tipo II/complicaciones , Dislipidemias/diagnóstico , Dislipidemias/genética , Dislipidemias/complicaciones , LípidosRESUMEN
Cannabis access laws allow for the use of cannabis in private and the trade, purchase and use of hemp-related products as a complementary medicine and for other benefits. Cannabidiol (CBD) has the treatment potential for several conditions but, with the lack of resources in South Africa to maintain the legislation, products contaminated with delta-9-tetrahydrocannabinol (Δ9-THC) are sold by some suppliers who do not comply with the legislative provisions in terms of the threshold concentrations for Δ9-THC. This dilemma complicates a medical review officer's decision regarding intentional use of Δ9-THC or otherwise, since a CBD user may have purchased the product legally and in good faith. Hemp- and CBD-containing products were analysed by gas chromatography-mass spectrometry and compliance was assessed for CBD and Δ9-THC purity against the legislative thresholds. A strategy based on metabolite ratios is suggested to distinguish between intentional or irresponsible cannabis use and legitimate CBD use.
Asunto(s)
Cannabidiol/química , Cannabidiol/farmacología , Dronabinol/química , Dronabinol/farmacología , Control de Medicamentos y Narcóticos/legislación & jurisprudencia , Publicidad , Comercio , Contaminación de Medicamentos , Cromatografía de Gases y Espectrometría de Masas , Humanos , SudáfricaRESUMEN
The white-winged flufftail is listed as critically endangered, and limited knowledge about the species' ecology has been identified as a limiting factor to effectively conserving the bird. Little is known about the vegetation inhabited by the white-winged flufftail, which hampers the identification and management of its habitat. This study presents a fine-scale classification and description of the vegetation of wetland sites where the bird is known to be present. A plant phytosociological study was conducted to describe the plant communities and vegetation structure of the habitat. Three sites were selected at Verloren Valei Nature Reserve and two at Middelpunt Wetland, Mpumalanga, South Africa, shortly after the white-winged flufftail breeding season. A total of 60 sample plots were placed within the study sites, where all plant species present were recorded and identified. Other aspects such as plant height, water depth and anthropogenic influences were also documented. A modified TWINSPAN analysis resulted in the identification of three sub-communities that can be grouped into one major community. The Cyperaceae, Asteraceae and Poaceae families dominate the vegetation, with the sedges Carex austro-africana and Cyperus denudatus being dominant, and the grasses Leersia hexandra and Arundinella nepalensis co-dominant. The broad habitat structure consisted of medium to tall herbaceous plants (0.5-0.7 m) with shallow slow-flowing water.
RESUMEN
PURPOSE OF REVIEW: The functions, genetic variations and impact of apolipoprotein E on lipoprotein metabolism in general are placed in the context of clinical practice dealing with moderate dyslipidaemia as well as dysbetalipoproteinemia, a highly atherogenic disorder and lipoprotein glomerulopathy. RECENT FINDINGS: Additional variants of apolipoprotein E and participation of apolipoprotein E in inflammation are of interest. The mostly favourable effects of apolipoprotein E2 as well as the atherogenic nature of apolipoproteinE4, which has an association with cognitive impairment, are confirmed. The contribution of remnant lipoproteins of triglyceride-rich lipoproteins, of which dysbetalipoproteinemia represents an extreme, is explored in atherosclerosis. Mimetic peptides may present new therapeutic approaches. Apolipoprotein E is an important determinant of the lipid profile and cardiovascular health in the population at large and can precipitate dysbetalipoproteinemia and glomerulopathy. Awareness of apolipoprotein E polymorphisms should improve medical care.
Asunto(s)
Aterosclerosis , Dislipidemias , Hiperlipoproteinemia Tipo III , Apolipoproteínas E/genética , Aterosclerosis/genética , Humanos , Lípidos , TriglicéridosRESUMEN
Dysbetalipoproteinemia (DBL) is an uncommon condition characterized by a mixed hyperlipidemia due to accumulation of remnant lipoproteins and is highly atherogenic. Typically, DBL is an autosomal recessive condition requiring an additional metabolic stress with reduced apolipoprotein E (apoE) function. However, DBL is also described in patients with multiple myeloma without the characteristic apoE2/E2 mutation seen in familial DBL. Although the underlying pathogenesis in these cases is not fully characterized, it is thought to occur due to interference with apoE function by antibodies produced from clonal plasma cells. Such cases are referred to as hyperlipidemic myeloma (HLM) and have rarely been described in the literature. To our knowledge there is no prior description of HLM in HIV positive patients in Africa. We describe a case of HLM in an African woman with underlying HIV infection who presented with phenotypic and biochemical features of DBL that responded poorly to lipid lowering therapy.