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1.
Metabolomics ; 20(3): 45, 2024 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-38615312

RESUMEN

INTRODUCTION: Aspalathus linearis (commonly known as rooibos) is endemic to the Cape Floristic Region of South Africa and is a popular herbal drink and skin phytotherapeutic ingredient, with health benefits derived primarily from its unique phenolic content. Several, seemingly habitat-specific ecotypes from the Cederberg (Western Cape) and Northern Cape have morphological, ecological, genetic and biochemical differences. OBJECTIVES AND METHODS: Despite the commercial popularity of the cultivated variety, the uncultivated ecotypes are largely understudied. To address gaps in knowledge about the biochemical constituency, ultra-performance liquid chromatography-mass spectrometry analysis of fifteen populations was performed, enabling high-throughput metabolomic fingerprinting of 50% (v/v) methanolic extracts. Antioxidant screening of selected populations was performed via three assays and antimicrobial activity on two microbial species was assessed. The metabolomic results were corroborated with total phenolic and flavonoid screening of the extracts. RESULTS AND DISCUSSION: Site-specific chemical lineages of rooibos ecotypes were confirmed via multivariate data analyses. Important features identified via PLS-DA disclosed higher relative abundances of certain tentative metabolites (e.g., rutin, aspalathin and apiin) present in the Dobbelaarskop, Blomfontein, Welbedacht and Eselbank sites, in comparison to other locations. Several unknown novel metabolites (e.g., m/z 155.0369, 231.0513, 443.1197, 695.2883) are responsible for metabolomic separation of the populations, four of which showed higher amounts of key metabolites and were thus selected for bioactivity analysis. The Welbedacht and Eselbank site 2 populations consistently displayed higher antioxidant activities, with 2,2-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities of 679.894 ± 3.427 µmol Trolox/g dry matter and 635.066 ± 5.140 µmol Trolox/g dry matter, respectively, in correlation with a high number of phenolic and flavonoid compounds. The contribution of the individual metabolites to the pharmacological effectiveness of rooibos remains unknown and as such, further structural elucidation and phytopharmacological testing is thus urgently needed.


Asunto(s)
Aspalathus , Antioxidantes , Ecotipo , Metabolómica , Flavonoides , Fenoles
2.
Hautarzt ; 67(7): 549-52, 2016 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-27106503

RESUMEN

Psoriasis is a chronic inflammatory disorder of the epidermis, which can be induced by systemic factors, such as streptococci infections or drugs. In addition, psoriasis can be caused by a local cutaneus trauma, known as Koebner phenomenon. Here, we describe a woman with psoriasis in remission, who developed a new psoriatic lesion due to a cutaneous infection with Borrelia burgdorferi. After causal therapy with doxycycline, the erythema migrans and psoriasis lesions disappeared.


Asunto(s)
Doxiciclina/uso terapéutico , Eritema/tratamiento farmacológico , Eritema/patología , Psoriasis/tratamiento farmacológico , Psoriasis/patología , Antibacterianos/administración & dosificación , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Resultado del Tratamiento
3.
J Am Soc Nephrol ; 25(9): 1991-2002, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24676636

RESUMEN

FSGS is characterized by segmental scarring of the glomerulus and is a leading cause of kidney failure. Identification of genes causing FSGS has improved our understanding of disease mechanisms and points to defects in the glomerular epithelial cell, the podocyte, as a major factor in disease pathogenesis. Using a combination of genome-wide linkage studies and whole-exome sequencing in a kindred with familial FSGS, we identified a missense mutation R431C in anillin (ANLN), an F-actin binding cell cycle gene, as a cause of FSGS. We screened 250 additional families with FSGS and found another variant, G618C, that segregates with disease in a second family with FSGS. We demonstrate upregulation of anillin in podocytes in kidney biopsy specimens from individuals with FSGS and kidney samples from a murine model of HIV-1-associated nephropathy. Overexpression of R431C mutant ANLN in immortalized human podocytes results in enhanced podocyte motility. The mutant anillin displays reduced binding to the slit diaphragm-associated scaffold protein CD2AP. Knockdown of the ANLN gene in zebrafish morphants caused a loss of glomerular filtration barrier integrity, podocyte foot process effacement, and an edematous phenotype. Collectively, these findings suggest that anillin is important in maintaining the integrity of the podocyte actin cytoskeleton.


Asunto(s)
Glomeruloesclerosis Focal y Segmentaria/genética , Proteínas de Microfilamentos/genética , Mutación , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adulto , Anciano , Secuencia de Aminoácidos , Animales , Movimiento Celular/genética , Secuencia Conservada , Proteínas Contráctiles/genética , Proteínas del Citoesqueleto/metabolismo , Análisis Mutacional de ADN , Modelos Animales de Enfermedad , Exoma , Femenino , Técnicas de Silenciamiento del Gen , Barrera de Filtración Glomerular/metabolismo , Glomeruloesclerosis Focal y Segmentaria/patología , Humanos , Masculino , Ratones , Persona de Mediana Edad , Datos de Secuencia Molecular , Proteínas Mutantes/genética , Linaje , Podocitos/metabolismo , Homología de Secuencia de Aminoácido , Regulación hacia Arriba , Pez Cebra , Proteínas de Pez Cebra/genética
4.
Front Pharmacol ; 14: 1294997, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38235116

RESUMEN

Stevens' Cure (Umckaloabo) emerged as a patent medicine claiming to treat tuberculosis in the United Kingdom at the beginning of the 20th century. However, due to its identity being shrouded in secrecy, it was never truly accepted by the medical community. It was "rediscovered" in the 1970s and subsequently developed into a very popular and successful phytopharmaceutical for the treatment of upper respiratory tract infections. Whether Stevens' Cure contained the same ingredient(s) as the modern Umckaloabo has not yet been demonstrated. We attempted to elucidate for the first time the identity of the original ingredient by comparative analysis of historical product samples. Three historical samples of Stevens' Cure were compared with Pelargonium sidoides DC. and P. reniforme Curt. root per UPLC-MS analysis. We confirm that the ingredient-P. sidoides DC.-is indeed the same as used in modern phytotherapy. We also attribute the first ethnopharmacological record of P. sidoides DC. being used for the treatment of tuberculosis to C. H. Stevens, the "creator" of Umckaloabo.

5.
CJEM ; 25(1): 48-56, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36577931

RESUMEN

PURPOSE: Point-of-care ultrasonography (POCUS) is an established tool in the management of hypotensive patients in the emergency department (ED). We compared the diagnostic accuracy of a POCUS protocol versus standard assessment without POCUS in patients with undifferentiated hypotension. METHODS: This was an international, multicenter randomized controlled trial included three EDs in North America and three in South Africa from September 2012 to December 2016. Hypotensive patients were randomized to early POCUS protocol plus standard care (POCUS group) or standard care without POCUS (control group). Initial and secondary diagnoses were recorded at 0 and 60 min. The main outcome was measures of diagnostic accuracy of a POCUS protocol in differentiating between cardiogenic and non-cardiogenic shock. Secondary outcomes were diagnostic performance for shock sub-types, as well as changes in perceived category of shock and overall diagnosis. RESULTS: Follow-up was completed for 270 of 273 patients. For cardiogenic shock, the POCUS-based diagnostic approach (POCUS) performed similarly to the non-POCUS approach (control) for specificity [95.5% (89.9-98.5) vs.93.8% (87.7-97.5)]; positive likelihood ratio (17.92 vs 14.80); negative likelihood ratio (0.21 vs 0.09) and diagnostic odds ratio (85.6 vs 166.57), with a similar overall diagnostic accuracy between the two approaches [93.7% (88-97.2) vs 93.6% (87.8-97.2)]. Diagnostic performance measures were similar across sub-categories of shock. CONCLUSION: This is the first randomized controlled trial to compare diagnostic performance of a POCUS protocol to standard care without POCUS in undifferentiated hypotensive ED patients. POCUS performed well diagnostically in undifferentiated hypotensive patients, especially as a rule-in test; however, performance did not differ meaningfully from standard assessment.


RéSUMé: OBJECTIF: L'échographie au point d'intervention (POCUS) est un outil bien établi dans la gestion des patients hypotendus dans le service des urgences. Nous avons comparé la précision diagnostique d'un protocole POCUS par rapport à une évaluation standard sans POCUS chez des patients présentant une hypotension indifférenciée. MéTHODES: Il s'agissait d'un essai contrôlé randomisé international multicentrique incluant 3 services d'urgence en Amérique du Nord et 3 en Afrique du Sud de septembre 2012 à décembre 2016. Les patients hypotenseurs ont été répartis par randomisation selon le protocole POCUS précoce plus les soins standard (groupe POCUS) ou les soins standard sans POCUS (groupe témoin). Les diagnostics initiaux et secondaires ont été enregistrés à 0 et 60 minutes. Le principal résultat était la mesure de la précision diagnostique d'un protocole POCUS pour différencier le choc cardiogénique du choc non cardiogénique. Les résultats secondaires étaient la performance diagnostique pour les sous-types de chocs, ainsi que les changements dans la perception de la catégorie de choc et du diagnostic global. RéSULTATS: Le suivi a été complété pour 270 des 273 patients. Pour le choc cardiogénique, l'approche diagnostique basée sur le POCUS (POCUS) a donné des résultats similaires à l'approche non-POCUS (Contrôle) pour la spécificité (95,5 % (89,9­98,5) vs 93,8 % (87,7­97,5)) ; Rapport de vraisemblance positif (17,92 vs 14,80) ; Le rapport de vraisemblance négatif (0,21 vs 0,09) et le rapport de cotes diagnostiques (85,6 vs 166,57), avec une précision diagnostique globale similaire entre les deux approches (93,7 % (88­97,2) vs 93,6 % (87,8­97,2). Les mesures de performance diagnostique étaient similaires dans toutes les sous-catégories de choc. CONCLUSION: Il s'agit du premier essai contrôlé randomisé visant à comparer la performance diagnostique d'un protocole POCUS aux soins standard sans POCUS chez des patients hypotendus indifférenciés aux urgences. La POCUS a donné de bons résultats diagnostiques chez les patients hypotendus indifférenciés, surtout en tant que test de référence ; cependant, les performances ne diffèrent pas de manière significative de l'évaluation standard.


Asunto(s)
Hipotensión , Choque , Humanos , Sistemas de Atención de Punto , Ultrasonografía/métodos , Hipotensión/diagnóstico por imagen , Choque/diagnóstico por imagen , Servicio de Urgencia en Hospital , Choque Cardiogénico
6.
Plant Dis ; 96(6): 881-888, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30727350

RESUMEN

Fusarium ear rot of maize, caused by Fusarium verticillioides, is an important disease affecting maize production worldwide. Apart from reducing yield and grain quality, F. verticillioides produces fumonisins which have been associated with mycotoxicoses of animals and humans. Currently, no maize breeding lines are known with resistance to F. verticillioides in South Africa. The objective of this study, therefore, was to evaluate 24 genetically diverse maize inbred lines as potential sources of resistance to Fusarium ear rot and fumonisin accumulation in field trials at Potchefstroom and Vaalharts in South Africa. After artificial silk channel inoculation with F. verticillioides, Fusarium ear rot development was determined at harvest and fumonisins B1, B2, and B3 quantified. A significant inbred line by location effect was observed for Fusarium ear rot severity (P ≤ 0.001), although certain lines proved to be consistently resistant across both locations. The individual inbred lines also differed considerably in fumonisin accumulation between Potchefstroom and Vaalharts, with differentiation between susceptible and potentially resistant inbred lines only being possible at Vaalharts. A greenhouse inoculation trial was then also performed on a subset of potentially resistant and highly susceptible lines. The inbred lines CML 390, CML 444, CML 182, VO 617Y-2, and RO 549 W consistently showed a low Fusarium ear rot (<5%) incidence at both Potchefstroom and Vaalharts and in the greenhouse. Two of these inbred lines, CML 390 and CML 444, accumulated fumonisin levels <5 mg kg-1. These lines could potentially act as sources of resistance for use within a maize breeding program.

7.
Forensic Sci Int ; 320: 110680, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33461004

RESUMEN

Senecio coronatus (known as izonkozonko and ubulibazi in Zulu) is commonly used in traditional medicine in South Africa as purification purgative and enemas for infants during weaning. We show for the first time that this species does not contain pyrrolizidine alkaloids and that reported cases of fatal hepatic sinusoidal obstruction syndrome in infants were caused by wrongly identified Senecio species containing large amounts of retrorsine-N-oxide. A validated ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method for the detection and quantitation of pyrrolizidine alkaloids is described.


Asunto(s)
Medicinas Tradicionales Africanas , Alcaloides de Pirrolicidina/análisis , Alcaloides de Pirrolicidina/envenenamiento , Senecio/química , Cromatografía Liquida , Toxicología Forense , Enfermedad Veno-Oclusiva Hepática/inducido químicamente , Humanos , Lactante , Sudáfrica , Espectrometría de Masas en Tándem , Destete
8.
Neuron ; 109(11): 1791-1809.e11, 2021 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-33979635

RESUMEN

Optical manipulations of genetically defined cell types have generated significant insights into the dynamics of neural circuits. While optogenetic activation has been relatively straightforward, rapid and reversible synaptic inhibition has proven more elusive. Here, we leveraged the natural ability of inhibitory presynaptic GPCRs to suppress synaptic transmission and characterize parapinopsin (PPO) as a GPCR-based opsin for terminal inhibition. PPO is a photoswitchable opsin that couples to Gi/o signaling cascades and is rapidly activated by pulsed blue light, switched off with amber light, and effective for repeated, prolonged, and reversible inhibition. PPO rapidly and reversibly inhibits glutamate, GABA, and dopamine release at presynaptic terminals. Furthermore, PPO alters reward behaviors in a time-locked and reversible manner in vivo. These results demonstrate that PPO fills a significant gap in the neuroscience toolkit for rapid and reversible synaptic inhibition and has broad utility for spatiotemporal control of inhibitory GPCR signaling cascades.


Asunto(s)
Inhibición Neural , Optogenética/métodos , Terminales Presinápticos/metabolismo , Recompensa , Transmisión Sináptica , Animales , Dopamina/metabolismo , Exocitosis , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Ácido Glutámico/metabolismo , Células HEK293 , Células HeLa , Humanos , Masculino , Ratones , Terminales Presinápticos/fisiología , Receptores Acoplados a Proteínas G/metabolismo , Opsinas de Bastones/genética , Opsinas de Bastones/metabolismo , Ácido gamma-Aminobutírico/metabolismo
9.
BMC Res Notes ; 13(1): 522, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-33172494

RESUMEN

OBJECTIVE: Current global trends on natural therapeutics suggest an increasing market interest toward the use and discovery of new plant-derived therapeutic compounds, often referred to as traditional medicine (TM). The Cannabis industry is currently one such focal area receiving attention, owing to the occurrence of phytocannabinoids (pCBs) which have shown promise in health-promotion and disease prevention. However, the occurrence of pCBs in other plant species are often overlooked and rarely studied. Leonotis leonurus (L.) R. Br. is endemic to South Africa with a rich history of use in TM practices amongst indigenous people and, has been recorded to induce mild psychoactive effects akin to Cannabis. While the leaves have been well-reported to contain therapeutic phytochemicals, little information exists on the flowers. Consequently, as part of a larger research venture, we targeted the flowers of L. leonurus for the identification of potential pCB or pCB-like compounds. RESULTS: Flower extracts were separated and analyzed using high performance thin layer chromatography (HPTLC). A single pCB candidate was isolated from HPTLC plates and, using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), we could successfully group this compound as a fatty amide and tentatively identified as 7,10,13,16-Docosatetraenoylethanolamine (adrenoyl-EA), a known bioactive compound.


Asunto(s)
Lamiaceae , Leonurus , Plantas Medicinales , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Flores , Humanos , Extractos Vegetales , Sudáfrica , Espectrometría de Masas en Tándem
10.
J Dairy Sci ; 92(5): 2046-50, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19389962

RESUMEN

Eight lactating Holstein cows were randomly allotted to 2 groups in a trial to establish whether a pathway exists for the transmission of melamine from feed to milk. All cows received oat hay ad libitum and 15 kg of concentrate pellets per cow daily. The concentrate pellets contained either melamine-contaminated corn gluten meal of Chinese origin (melamine treatment) or locally produced melamine-free corn gluten meal (control treatment). Cows in the melamine treatment ingested 17.1 g of melamine per day. Cows were milked twice daily, and milk samples were taken once daily during the afternoon milking for melamine and milk component analyses. Melamine appeared in the milk within 8 h after first ingestion of the melamine containing pellets. Melamine concentration reached a maximum of 15.7 mg/kg within 56 h after first ingestion, with an excretion efficiency of approximately 2%. Milk solids and milk urea nitrogen were not affected by treatment. The melamine concentration dropped rapidly after changing all cows back to the control pellets, but melamine only declined to undetectable levels in the milk more than 6 d (152 h) after last ingestion of melamine. Results from the current trial are important to the feed and dairy industries because, until now, any melamine found in milk and milk products was attributed only to the deliberate external addition of melamine to these products, not to adulterated ingredients in animal feeds.


Asunto(s)
Alimentación Animal/análisis , Bovinos/metabolismo , Contaminación de Alimentos/análisis , Leche/química , Triazinas/metabolismo , Animales , Dieta/veterinaria , Femenino , Lactancia/fisiología , Leche/metabolismo , Distribución Aleatoria , Factores de Tiempo , Triazinas/farmacocinética
11.
PLoS One ; 14(2): e0212972, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30811510

RESUMEN

Kenya has the world's 4th largest HIV burden. Various strategies to control the epidemic have been implemented, including the implementation of viral load (VL) testing to monitor HIV patients on ARVs. Like many resource limited settings, Kenya's healthcare system faces serious challenges in effectively providing quality health services to its population. Increased investments to strengthen the country's capacity to diagnose, monitor and treat diseases, particularly HIV and TB, continue to be made but are still inadequate in the face of global health goals like the UNAIDS 90:90:90 which require scaling up of VL tests amid existing constraints. In Kenya, there is an increase in the demand for VL tests amidst these existing constraints. The GeneXpert system is a diagnostic point-of-care technology that can quantify, amongst others, HIV VL. Currently, GeneXpert technology is widely distributed in Kenya for testing of tuberculosis. This study aimed to determine the economic and public health impact of incorporating VL test modules on the existing GeneXpert infrastructure. Markov models were constructed for different populations (non-pregnant adults, pregnant women and children). The scenarios analysed were 100% centralized VL testing compared to 50% GeneXpert plus 50% centralized VL testing, with time horizons of 5 years for the adult and child populations, and 31 months for the pregnant population. Incremental effectiveness was measured in terms of the number of HIV transmissions or opportunistic infections avoided when implementing the GeneXpert scenario compared to a 100% centralized scenario. The model indicated that, for all three populations combined, the GeneXpert scenario resulted in 117 less HIV transmissions and 393 less opportunistic infections. The cost decreased by $21,978,755 for the non-pregnant and pregnant adults and $22,808,533 for non-pregnant adults, pregnant adults and children. The model showed that GeneXpert would cost less and be more effective in terms of total cost per HIV transmission avoided and the total cost per opportunistic infection avoided, except for the pregnant population, when considered separately.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , VIH/aislamiento & purificación , Sistemas de Atención de Punto/economía , Adolescente , Fármacos Anti-VIH/farmacología , Niño , Preescolar , Costo de Enfermedad , Femenino , VIH/efectos de los fármacos , VIH/genética , Infecciones por VIH/virología , Humanos , Lactante , Recién Nacido , Kenia , Masculino , Cadenas de Markov , Modelos Teóricos , Embarazo , Salud Pública , Resultado del Tratamiento , Carga Viral
12.
J Med Genet ; 43(6): 517-22, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16339849

RESUMEN

INTRODUCTION: Variant R620W of protein tyrosine phosphatase non-receptor type 22 (PTPN22) has consistently been reported as a susceptibility factor for several autoimmune diseases. We investigated its role in susceptibility to psoriasis, the relevance of possibly other disease-causing variants, and interdependency of the major risk factor for psoriasis at PSORS1. METHODS: R620W was tested in a case-control study initially with 375 German patients and then with an enlarged sample of an additional 418 patients. Analyses were extended to linkage disequilibrium (LD) based haplotypes. Potential interaction between risk haplotypes of PTPN22 and the PSORS1 associated risk allele was tested by regression analysis. PTPN22 coding sequence was determined in 20 patients carrying the risk haplotype. Association and regression analysis were also performed in the extended case-control study. RESULTS: R620W was not associated in either case-control study, while significant association (corrected for multiple testing) with one haplotype (C-4) of the LD block encompassing PTPN22 as well with another haplotype (B-3) within an adjacent telomeric LD block was detected. No evidence for interaction between risk haplotype C-4 and the PSORS1 associated risk allele was found. Sequencing excluded other coding variants within PTPN22 as a basis for association findings. Analysis of the extended study group confirmed association for haplotypes B-3 and C-4 and independence of risk haplotypes C-4 and PSORS1. DISCUSSION: We exclude a major role of *620W in German psoriasis patients but suggest that other susceptibility determinant(s) within non-coding regions of PTPN22 or its proximity might exist acting independently of the major PSORS1 risk factor.


Asunto(s)
Predisposición Genética a la Enfermedad , Proteínas Tirosina Fosfatasas/genética , Psoriasis/genética , Alelos , Estudios de Casos y Controles , Análisis Mutacional de ADN , Femenino , Alemania , Haplotipos , Humanos , Desequilibrio de Ligamiento , Masculino , Mutación Missense , Polimorfismo de Nucleótido Simple , Proteína Tirosina Fosfatasa no Receptora Tipo 22 , Psoriasis/diagnóstico , Factores de Riesgo
13.
MMW Fortschr Med ; 148(43): 33-4, 2006 Oct 26.
Artículo en Alemán | MEDLINE | ID: mdl-17619421

RESUMEN

The lumbar facet syndrome (LFS) is a frequent cause of chronic backaches. A reliable diagnosis can be made through repeated facet blockades.The diagnosis is considered confirmed if the pain is significantly reduced over several hours. In addition to oral pain medication and physical measures, alternative minimally invasive therapeutic possibilities include surgical stabilization, as well as facet joint denervation. Both can be performed as thermodenervation or cryotherapy.


Asunto(s)
Dolor de Espalda/etiología , Vértebras Lumbares , Espondiloartritis/diagnóstico , Anestésicos Locales/administración & dosificación , Dolor de Espalda/diagnóstico , Bupivacaína/administración & dosificación , Crioterapia , Humanos , Inyecciones Espinales , Síndromes de Compresión Nerviosa/diagnóstico , Síndromes de Compresión Nerviosa/terapia , Examen Neurológico , Raíces Nerviosas Espinales , Espondiloartritis/terapia
14.
J Clin Invest ; 126(3): 1067-78, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26901816

RESUMEN

Focal segmental glomerulosclerosis (FSGS) is a syndrome that involves kidney podocyte dysfunction and causes chronic kidney disease. Multiple factors including chemical toxicity, inflammation, and infection underlie FSGS; however, highly penetrant disease genes have been identified in a small fraction of patients with a family history of FSGS. Variants of apolipoprotein L1 (APOL1) have been linked to FSGS in African Americans with HIV or hypertension, supporting the proposal that genetic factors enhance FSGS susceptibility. Here, we used sequencing to investigate whether genetics plays a role in the majority of FSGS cases that are identified as primary or sporadic FSGS and have no known cause. Given the limited number of biopsy-proven cases with ethnically matched controls, we devised an analytic strategy to identify and rank potential candidate genes and used an animal model for validation. Nine candidate FSGS susceptibility genes were identified in our patient cohort, and three were validated using a high-throughput mouse method that we developed. Specifically, we introduced a podocyte-specific, doxycycline-inducible transactivator into a murine embryonic stem cell line with an FSGS-susceptible genetic background that allows shRNA-mediated targeting of candidate genes in the adult kidney. Our analysis supports a broader role for genetic susceptibility of both sporadic and familial cases of FSGS and provides a tool to rapidly evaluate candidate FSGS-associated genes.


Asunto(s)
Glomeruloesclerosis Focal y Segmentaria/genética , Animales , Estudios de Casos y Controles , Células Cultivadas , Análisis Mutacional de ADN , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Masculino , Ratones Transgénicos , Polimorfismo de Nucleótido Simple
15.
Oncogene ; 17(18): 2323-32, 1998 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-9811463

RESUMEN

Nitric oxide (NO) is thought to play an important role in neurotransmission, inflammation, and regulation of cell death in the mammalian brain. Here, we examined the synthesis and biological effects of NO in human malignant glioma cells. Exposure to cytokines such as interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha or interleukin (IL)-1beta and lipopolysaccharide (LPS) induced NO synthesis in rat C6 and A172 human glioma cells, but not in LN-229, T98G or LN-18 human malignant glioma cells. Induced release of NO involved enhanced expression of inducible NO synthase (iNOS). Failure to detect NO release in the latter cell lines was not overcome by neutralization of endogenous TGF-beta or by coexposure to cytokines, LPS, and antioxidants. Apoptosis induced by CD95 ligand (CD95L) did not involve NO formation. Neither NOS inhibitors nor NO donators modulated CD95L-induced apoptosis. Dexamethasone (DEX)-mediated protection of glioma cells from CD95L-induced apoptosis was also independent of DEX effects on NO metabolism. DEX inhibited not only cytokine/LPS-evoked NO release but also attenuated the toxicity of NO in three of five cell lines. Forced expression of temperature-sensitive p53 val135 in C6 cells in either mutant or wild-type conformation inhibited cytokine/LPS-induced NO synthesis. Further, accumulation of p53 in both mutant or wild-type conformation protected glioma cells from the toxicity of exogenous NO, consistent with a gain of p53 function associated with p53 accumulation. We conclude that resistance to NO-dependent immune defense mechanisms may contribute to the malignant progression of human cancers with p53 alterations, notably those associated with the accumulation of mutant p53 protein.


Asunto(s)
Apoptosis , Citocinas/farmacología , Genes p53/fisiología , Glioma/metabolismo , Proteínas de Neoplasias/biosíntesis , Óxido Nítrico Sintasa/biosíntesis , Óxido Nítrico/biosíntesis , Proteína p53 Supresora de Tumor/metabolismo , Animales , Antineoplásicos Hormonales/farmacología , Cicloheximida/farmacología , Dexametasona/farmacología , Genes p53/genética , Glioma/genética , Glioma/patología , Humanos , Interleucina-1/farmacología , Lipopolisacáridos/farmacología , Óxido Nítrico/farmacología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa de Tipo II , Inhibidores de la Síntesis de la Proteína/farmacología , Ratas , Factor de Crecimiento Transformador alfa/farmacología , Factor de Crecimiento Transformador beta/farmacología , Células Tumorales Cultivadas , Receptor fas/fisiología
16.
J Invest Dermatol ; 106(4): 711-4, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8618009

RESUMEN

To further evaluate the nature of the HLA association with psoriasis, HLA haplotypes of 60 patients with type 1 (early onset, positive family history) and 30 patients with type II (late onset, no family history) psoriasis were investigated by polymerase chain reaction sequence-specific oligonucleotide hybridization (HLA class II) and serology (HLA class I). Ethnically matched blood donors (146) served as controls. In type I, but not type II psoriasis, the Caucasian HLA extended haplotype (EH) Cw6-B57-DRB1*0701-DQA1*0201-DQB1*0303 named according to the B allele EH-57.1 was highly significantly overrepresented (p cor= 0.00021). This particular EH was present in 35% of type I psoriatics but only 2% of controls. EH-57.1+ individuals therefore carry a 26 times higher risk of developing type I psoriasis than individuals who are EH-57.1-negative Further analysis of individual HLA alleles revealed that within EH-57.1, HLA class I antigens (Cw6-B57) were associated to a much higher extent with type I psoriasis than the HLA class II alleles (DRB1*0701-DQA1*0201-DQB1* 0303). Pedigree analysis of three multiply affected families over three generations revealed a cosegregation of disease with EH-57.1. These results strongly suggest that a gene for familial psoriasis is associated with the class I side of the extended haplotype Cw6-B57-DRB1*0701-DQA1*0201-DQB1*0303.


Asunto(s)
Antígenos HLA-B/genética , Antígenos HLA-C/genética , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Haplotipos , Psoriasis/inmunología , Secuencia de Bases , Cadenas alfa de HLA-DQ , Cadenas beta de HLA-DQ , Cadenas HLA-DRB1 , Humanos , Datos de Secuencia Molecular , Psoriasis/genética
17.
J Invest Dermatol ; 97(6): 1053-6, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1836218

RESUMEN

In nonpustular psoriasis, principally two forms can be distinguished [Christophers E. Henseler T: Patient subgroups and the inflammatory pattern in psoriasis. Acta Dermatol Venereol 69(suppl 151):88-92, 1989): Type I frequently shows positive family history, linkage disequilibrium for human leucocyte antigens (HLAs) Cw6, B13 and Bw57 as well as an early onset. Type II manifests itself around the 5th decade, it is more frequently than normal associated with Cw2 and B27. In the light of this association with HLAs an autoimmune pathogenesis has been discussed. In order to investigate the pathogenetic function of T cells we obtained biopsies from patients with type I (n = 10) and type II (n = 10) psoriasis. Three-step peroxidase staining was performed using a panel of monoclonal antibodies directed against five variable (V) regions of the beta chain (V beta 5a, V beta 5b, V beta 6, V beta 8, V beta 12) and one of the alpha chain (V alpha 2) of the T cell receptor (TCR). Positive or negative selection of a particular TCR V region could not be detected in the demonstrable repertoire. Furthermore, the usage of the V regions under investigation revealed a similar pattern in the two forms of psoriasis.


Asunto(s)
Región Variable de Inmunoglobulina/análisis , Psoriasis/patología , Receptores de Antígenos de Linfocitos T/inmunología , Piel/ultraestructura , Adulto , Alelos , Antígenos de Diferenciación de Linfocitos T/análisis , Complejo CD3 , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Región Variable de Inmunoglobulina/genética , Recién Nacido , Receptores de Antígenos de Linfocitos T/análisis
18.
J Invest Dermatol ; 100(6): 749-52, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8496614

RESUMEN

Although the pathogenesis of psoriasis is still a matter of debate, there are several lines of evidence supporting the concept of this disease being immunologically mediated with T cells playing a crucial role. Because a considerable portion of the cellular infiltrate in psoriasis consists of activated T-helper cells, expression of HLA class II antigens might be of particular importance for the understanding of its pathogenesis. Therefore, we investigated the HLA type of patients with type I (early onset, positive family history) and type II (late onset, no family history) psoriasis by means of serology (n = 89) and genotyping using sequence-specific oligonucleotide probes (n = 64). Serologic analysis of class I documented the association of type I psoriasis with HLA-Cw6, -B13, and -B57, whereas type II psoriasis showed a weaker correlation with HLA-Cw2 and -B27. Genotyping using SSO for class II detected the elevation of the HLA-DRB1*0701/2 allele frequency from 13% in normal population to 36% in type I, but only to 15% in type II psoriatics. Moreover, positive correlations with type I psoriasis were detected for HLA-DQA1*0201 and HLA-DQB1*0303. The HLA-DRB1*0701/2, -DQA1*0201, -DQB1*0303 extended haplotype was found exclusively in type I psoriasis. This is the first report documenting the association of distinct HLA class II alleles with type I psoriasis as detected on the DNA level, an approach both more specific and more sensitive when compared to serology.


Asunto(s)
Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Antígenos de Histocompatibilidad Clase II/genética , Sondas de Oligonucleótidos , Psoriasis/inmunología , Adulto , Secuencia de Bases , Antígenos HLA-DQ/sangre , Cadenas alfa de HLA-DQ , Cadenas beta de HLA-DQ , Antígenos HLA-DR/sangre , Cadenas HLA-DRB1 , Haplotipos , Antígenos de Histocompatibilidad Clase II/sangre , Prueba de Histocompatibilidad , Humanos , Datos de Secuencia Molecular
19.
J Neuroimmunol ; 99(1): 13-8, 1999 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-10496172

RESUMEN

Decorin gene therapy for experimental malignant glioma is thought to involve antagonism of immunosuppression induced by glioma-derived transforming growth factor-beta (TGF-beta). TGF-beta is chemotactic for cells of the monocyte macrophage lineage but inhibits their functional activity in many in vitro paradigms. Here, we examined changes in the patterns of microglial infiltration of rat C6 gliomas expressing a decorin transgene. We find that the number of OX42/ED-1-positive microglial cells is reduced rather than enhanced in the presence of decorin. Decorin-expressing gliomas contain lower numbers of MHC class II antigen-expressing microglial cells whereas the relative frequency of MHC I immunoreactivity among microglial cells is increased. Interestingly, the reduction of TGF-beta levels in the tumors by decorin is associated with the de novo expression of inducible nitric oxide synthase (iNOS) in a minority of microglial cells. These data suggest that microglial cells do not participate in the regression of decorin-expressing rat C6 gliomas.


Asunto(s)
Neoplasias Encefálicas/patología , Cuerpo Estriado/patología , Glioma/patología , Microglía/patología , Proteoglicanos/fisiología , Animales , Neoplasias Encefálicas/inmunología , Decorina , Proteínas de la Matriz Extracelular , Femenino , Glioma/inmunología , Humanos , Técnicas para Inmunoenzimas , Microglía/inmunología , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología , Trasplante de Neoplasias , Proteínas del Tejido Nervioso/análisis , Óxido Nítrico Sintasa/análisis , Óxido Nítrico Sintasa de Tipo II , Proteoglicanos/genética , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes de Fusión/fisiología , Transfección , Factor de Crecimiento Transformador beta/análisis , Células Tumorales Cultivadas/trasplante
20.
J Neurol ; 245(3): 169-72, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9553848

RESUMEN

p53 immunoreactivity and humoral immune response to p53 were examined in 14 patients with malignant glioma, including 4 patients with leptomeningeal glioma cell dissemination. Twelve patients expressed p53 protein within the tumour tissue. p53 antibodies were detected in the serum in 2 of 14 patients but never in the cerebrospinal fluid (CSF). Soluble p53 protein was detected neither in serum nor in CSF of the glioma patients. CSF levels of the immunosuppressive cytokine, transforming growth factor (TGF)-beta, were elevated in the glioma patients, including those with a humoral response to p53. These preliminary findings raise the possibility of systemic humoral immune responses to antigens, including mutant p53, expressed by glioma cells in the central nervous system.


Asunto(s)
Autoanticuerpos/sangre , Neoplasias Encefálicas/inmunología , Glioma/inmunología , Proteína p53 Supresora de Tumor/inmunología , Adulto , Anciano , Autoanticuerpos/líquido cefalorraquídeo , Neoplasias Encefálicas/líquido cefalorraquídeo , Neoplasias Encefálicas/metabolismo , Femenino , Glioma/líquido cefalorraquídeo , Glioma/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Factor de Crecimiento Transformador beta/líquido cefalorraquídeo , Proteína p53 Supresora de Tumor/análisis
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