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1.
EMBO Rep ; 21(3): e47832, 2020 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-31951090

RESUMEN

Nicotinamide adenine dinucleotide (NAD) and its phosphorylated form (NADP) are vital for cell function in all organisms and form cofactors to a host of enzymes in catabolic and anabolic processes. NAD(P) transhydrogenases (NTHs) catalyse hydride ion transfer between NAD(H) and NADP(H). Membrane-bound NTH isoforms reside in the cytoplasmic membrane of bacteria, and the inner membrane of mitochondria in metazoans, where they generate NADPH. Here, we show that malaria parasites encode a single membrane-bound NTH that localises to the crystalloid, an organelle required for sporozoite transmission from mosquitos to vertebrates. We demonstrate that NTH has an essential structural role in crystalloid biogenesis, whilst its enzymatic activity is required for sporozoite development. This pinpoints an essential function in sporogony to the activity of a single crystalloid protein. Its additional presence in the apicoplast of sporozoites identifies NTH as a likely supplier of NADPH for this organelle during liver infection. Our findings reveal that Plasmodium species have co-opted NTH to a variety of non-mitochondrial organelles to provide a critical source of NADPH reducing power.


Asunto(s)
Malaria/transmisión , NADP Transhidrogenasas , Animales , Mitocondrias/genética , NAD , NADP , NADP Transhidrogenasas/genética
2.
Genomics ; 113(6): 4015-4021, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34637930

RESUMEN

HIV infects the CD4 cells which marks the suppression of our immune system. DNA from serum of healthy, treated and untreated HIV infected individuals was extracted. The DNA was subjected to 16S metagenomic sequencing and analyzed using QIIME2 pipeline. 16S sequencing analysis showed serum microbiome was dominated by Firmicutes, Proteobacteria, Bacteroidota and Actinobacteria. Treated HIV infection showed highest abundance of Firmicutes (66.40%) significantly higher than untreated HIV infection (35.88%) and control (41.89%). Bacilli was most abundant class in treated (63.59%) and second most abundant in untreated (34.53%) while control group showed highest abundance of class Gamma-proteobacteria (45.86%). Untreated HIV infection group showed Enterococcus (10.72%) and Streptococcus (6.599%) as the most abundant species. Untreated HIV infection showed significantly higher (p = 0.0039) species richness than treated and control groups. An altered serum microbiome of treated HIV infection and higher microbial abundance in serum of untreated HIV infection was observed.


Asunto(s)
Infecciones por VIH , Microbiota , Infecciones por VIH/genética , Humanos , Metagenoma , Metagenómica , ARN Ribosómico 16S/genética
3.
J Cutan Pathol ; 2018 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-29797343

RESUMEN

Epithelial sheath neuroma (ESN) is a rare entity, histologically showing enlarged nerves in the superficial dermis surrounded by cytologically bland keratinocytes, classically presenting clinically as an erythematous papule or nodule on the back of middle-aged to elderly individuals. Clear-cut recommendations for treatment are not available, with many reports citing biopsy alone or simple excision as curative. We report a case of biopsy-proven ESN presenting as a significantly painful nodule in an elderly woman. Surgical excision was performed for symptom control and the residual ESN was found to extend deep into the subcutis.

4.
J Pak Med Assoc ; 67(12): 1825-1832, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29256524

RESUMEN

OBJECTIVE: To estimate frequencies of metabolic risk phenotypes and their associations in body mass index and waist circumference-based obesity categories. METHODS: The cross-sectional study was conducted at Pir Mehr Ali Shah Arid Agriculture University, Rawalpindi, Pakistan, from August 2014 to March 2016. Anthropometric and clinical data of young adults was collected. All subjects were categorised into body mass index, waist circumference-based obesity categories and common metabolic risk phenotypes (hypertension, hyperglycaemia, dyslipidaemia) frequencies and their associations were estimated in age and gender adjusted models. Data was analysed using SPSS 21. RESULTS: Of the 2,000 participants, 800(40%) were females and 1,200(60%) were males. There were 500(25%) participants in each group, i.e. underweight, normal weight, overweight and obese. The overall mean age was 23.68±4.33 years (range: 16-30 years). All clinical parameters were significantly raised in general and abdominally obese class (p<0.05). Based on body mass index and waist circumference, the frequency of general obesity was 324(16.2%) and abdominal obesity was 994(49.7%). Co-morbid metabolic risk phenotypes were as follows: hypertension 1,098(54.9%) and 924(46.2%); hyperglycaemia 1,116(55.8%) and 550(27.5%); dyslipidaemia 300(15%) and 194(9.7%), respectively. The strongest associations of body mass index and waist circumference alone catergorised obesity were found with hyperglycaemia, (Odds ratio: 7.23, 6.49) followed by dyslipidemia (Odds ratio: 5.60, 5.67) and hypertension (Odds ratio: 3.28, 3.02). . CONCLUSIONS: Body mass index and waist circumference were found to be powerful, discriminating predictors of co-morbidities linked with general and abdominal obesity.


Asunto(s)
Índice de Masa Corporal , Diabetes Mellitus Tipo 2/epidemiología , Obesidad/epidemiología , Circunferencia de la Cintura/fisiología , Adolescente , Adulto , Antropometría , Enfermedades Cardiovasculares/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Pakistán/epidemiología , Factores de Riesgo , Adulto Joven
5.
J Biol Chem ; 290(14): 9273-83, 2015 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-25713077

RESUMEN

The ribbon-helix-helix (RHH) superfamily of DNA-binding proteins is dispersed widely in procaryotes. The dimeric RHH fold is generated by interlocking of two monomers into a 2-fold symmetrical structure that comprises four α-helices enwrapping a pair of antiparallel ß-strands (ribbon). Residues in the ribbon region are the principal determinants of DNA binding, whereas the RHH hydrophobic core is assembled from amino acids in both the α-helices and ribbon element. The ParG protein encoded by multiresistance plasmid TP228 is a RHH protein that functions dually as a centromere binding factor during segrosome assembly and as a transcriptional repressor. Here we identify residues in the α-helices of ParG that are critical for DNA segregation and in organization of the protein hydrophobic core. A key hydrophobic aromatic amino acid at one position was functionally substitutable by other aromatic residues, but not by non-aromatic hydrophobic amino acids. Nevertheless, intramolecular suppression of the latter by complementary change of a residue that approaches nearby from the partner monomer fully restored activity in vivo and in vitro. The interactions involved in assembling the ParG core may be highly malleable and suggest that RHH proteins are tractable platforms for the rational design of diverse DNA binding factors useful for synthetic biology and other purposes.


Asunto(s)
Centrómero , Proteínas de Escherichia coli/metabolismo , Proteínas Represoras/metabolismo , Secuencia de Aminoácidos , Dimerización , Proteínas de Escherichia coli/química , Interacciones Hidrofóbicas e Hidrofílicas , Datos de Secuencia Molecular , Proteínas Represoras/química
6.
Nature ; 463(7281): 666-70, 2010 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-19966786

RESUMEN

Obesity is a highly heritable and genetically heterogeneous disorder. Here we investigated the contribution of copy number variation to obesity in 300 Caucasian patients with severe early-onset obesity, 143 of whom also had developmental delay. Large (>500 kilobases), rare (<1%) deletions were significantly enriched in patients compared to 7,366 controls (P < 0.001). We identified several rare copy number variants that were recurrent in patients but absent or at much lower prevalence in controls. We identified five patients with overlapping deletions on chromosome 16p11.2 that were found in 2 out of 7,366 controls (P < 5 x 10(-5)). In three patients the deletion co-segregated with severe obesity. Two patients harboured a larger de novo 16p11.2 deletion, extending through a 593-kilobase region previously associated with autism and mental retardation; both of these patients had mild developmental delay in addition to severe obesity. In an independent sample of 1,062 patients with severe obesity alone, the smaller 16p11.2 deletion was found in an additional two patients. All 16p11.2 deletions encompass several genes but include SH2B1, which is known to be involved in leptin and insulin signalling. Deletion carriers exhibited hyperphagia and severe insulin resistance disproportionate for the degree of obesity. We show that copy number variation contributes significantly to the genetic architecture of human obesity.


Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 16/genética , Obesidad/genética , Obesidad/fisiopatología , Proteínas Adaptadoras Transductoras de Señales/genética , Edad de Inicio , Niño , Estudios de Cohortes , Variaciones en el Número de Copia de ADN/genética , Discapacidades del Desarrollo/complicaciones , Discapacidades del Desarrollo/genética , Estudio de Asociación del Genoma Completo , Heterocigoto , Humanos , Hiperfagia/genética , Patrón de Herencia/genética , Resistencia a la Insulina/genética , Mutación/genética , Obesidad/complicaciones , Obesidad/epidemiología , Reino Unido/epidemiología , Población Blanca
7.
Proc Natl Acad Sci U S A ; 109(43): 17537-42, 2012 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-22988082

RESUMEN

Adaptive features of innate immunity, recently described as "trained immunity," have been documented in plants, invertebrate animals, and mice, but not yet in humans. Here we show that bacille Calmette-Guérin (BCG) vaccination in healthy volunteers led not only to a four- to sevenfold increase in the production of IFN-γ, but also to a twofold enhanced release of monocyte-derived cytokines, such as TNF and IL-1ß, in response to unrelated bacterial and fungal pathogens. The enhanced function of circulating monocytes persisted for at least 3 mo after vaccination and was accompanied by increased expression of activation markers such as CD11b and Toll-like receptor 4. These training effects were induced through the NOD2 receptor and mediated by increased histone 3 lysine 4 trimethylation. In experimental studies, BCG vaccination induced T- and B-lymphocyte-independent protection of severe combined immunodeficiency SCID mice from disseminated candidiasis (100% survival in BCG-vaccinated mice vs. 30% in control mice). In conclusion, BCG induces trained immunity and nonspecific protection from infections through epigenetic reprogramming of innate immune cells.


Asunto(s)
Vacuna BCG/inmunología , Epigénesis Genética , Monocitos/inmunología , Proteína Adaptadora de Señalización NOD2/inmunología , Adulto , Linfocitos B/inmunología , Secuencia de Bases , Inmunoprecipitación de Cromatina , Cartilla de ADN , Histonas/metabolismo , Humanos , Metilación , Reacción en Cadena de la Polimerasa , Linfocitos T/inmunología
8.
Mol Microbiol ; 89(3): 552-64, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23773015

RESUMEN

A shared feature of the motile stages (zoites) of malaria parasites is a cortical cytoskeletal structure termed subpellicular network (SPN), thought to define and maintain cell shape. Plasmodium alveolins comprise structural components of the SPN, and alveolin gene knockout causes morphological abnormalities that coincide with markedly reduced tensile strength of the affected zoites, indicating the alveolins are prime cell shape determinants. Here, we characterize a novel SPN protein of Plasmodium berghei ookinetes and sporozoites named G2 (glycine at position 2), which is structurally unrelated to alveolins. G2 knockout abolishes parasite transmission and causes zoite malformations and motility defects similar to those observed in alveolin null mutants. Unlike alveolins, however, G2 contributes little to tensile strength, arguing against a cause-effect relationship between tensile strength and cell shape. We also show that G2 null mutant sporozoites display an abnormal arrangement of their subpellicular microtubules. These results provide important new understanding of the factors that determine zoite morphogenesis, as well as the potential roles of the cortical cytoskeleton in gliding motility.


Asunto(s)
Citoesqueleto/fisiología , Morfogénesis , Plasmodium berghei/citología , Proteínas Protozoarias/metabolismo , Secuencia de Aminoácidos , Forma de la Célula , Técnicas de Inactivación de Genes , Datos de Secuencia Molecular , Plasmodium berghei/genética , Proteínas Protozoarias/genética , Esporozoítos/citología , Resistencia a la Tracción
9.
Blood ; 120(19): 4038-48, 2012 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-22983443

RESUMEN

ERG and FLI1 are closely related members of the ETS family of transcription factors and have been identified as essential factors for the function and maintenance of normal hematopoietic stem cells. Here genome-wide analysis revealed that both ERG and FLI1 occupy similar genomic regions as AML1-ETO in t(8;21) AMLs and identified ERG/FLI1 as proteins that facilitate binding of oncofusion protein complexes. In addition, we demonstrate that ERG and FLI1 bind the RUNX1 promoter and that shRNA-mediated silencing of ERG leads to reduced expression of RUNX1 and AML1-ETO, consistent with a role of ERG in transcriptional activation of these proteins. Finally, we identify H3 acetylation as the epigenetic mark preferentially associated with ETS factor binding. This intimate connection between ERG/FLI1 binding and H3 acetylation implies that one of the molecular strategies of oncofusion proteins, such as AML1-ETO and PML-RAR-α, involves the targeting of histone deacetylase activities to ERG/FLI1 bound hematopoietic regulatory sites. Together, these results highlight the dual importance of ETS factors in t(8;21) leukemogenesis, both as transcriptional regulators of the oncofusion protein itself as well as proteins that facilitate AML1-ETO binding.


Asunto(s)
Subunidad alfa 2 del Factor de Unión al Sitio Principal/metabolismo , Epigénesis Genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Proteínas de Fusión Oncogénica/metabolismo , Proteína Proto-Oncogénica c-fli-1/metabolismo , Transactivadores/metabolismo , Acetilación , Antígenos CD34/metabolismo , Sitios de Unión , Transformación Celular Neoplásica/genética , Cromosomas Humanos Par 21 , Cromosomas Humanos Par 8 , Regulación Leucémica de la Expresión Génica , Células Madre Hematopoyéticas/metabolismo , Histonas/metabolismo , Humanos , Motivos de Nucleótidos , Unión Proteica , Proteínas Proto-Oncogénicas c-ets/metabolismo , Interferencia de ARN , Proteína 1 Compañera de Translocación de RUNX1 , Regulador Transcripcional ERG , Translocación Genética
10.
Blood ; 120(15): 3058-68, 2012 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-22923494

RESUMEN

Chromatin accessibility plays a key role in regulating cell type specific gene expression during hematopoiesis but has also been suggested to be aberrantly regulated during leukemogenesis. To understand the leukemogenic chromatin signature, we analyzed acute promyelocytic leukemia, a subtype of leukemia characterized by the expression of RARα-fusion proteins, such as PML-RARα. We used nuclease accessibility sequencing in cell lines as well as patient blasts to identify accessible DNA elements and identified > 100 000 accessible regions in each case. Using ChIP-seq, we identified H2A.Z as a histone modification generally associated with these accessible regions, whereas unsupervised clustering analysis of other chromatin features, including DNA methylation, H2A.Zac, H3ac, H3K9me3, H3K27me3, and the regulatory factor p300, distinguished 6 distinct clusters of accessible sites, each with a characteristic functional makeup. Of these, PML-RARα binding was found specifically at accessible chromatin regions characterized by p300 binding and hypoacetylated histones. Identifying regions with a similar epigenetic make up in t(8;21) acute myeloid leukemia (AML) cells, another subtype of AMLs, revealed that these regions are occupied by the oncofusion protein AML1-ETO. Together, our results suggest that oncofusion proteins localize to accessible regions and that chromatin accessibility together with p300 binding and histone acetylation characterize AML1-ETO and PML-RARα binding sites.


Asunto(s)
Cromatina/fisiología , Subunidad alfa 2 del Factor de Unión al Sitio Principal/metabolismo , Proteína p300 Asociada a E1A/metabolismo , Regulación Leucémica de la Expresión Génica , Histonas/metabolismo , Leucemia Mieloide Aguda/patología , Leucemia Promielocítica Aguda/patología , Proteínas de Fusión Oncogénica/metabolismo , Acetilación , Sitios de Unión , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Inmunoprecipitación de Cromatina , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Metilación de ADN , Proteína p300 Asociada a E1A/genética , Perfilación de la Expresión Génica , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteínas de Fusión Oncogénica/genética , Regiones Promotoras Genéticas , ARN Mensajero/genética , Proteína 1 Compañera de Translocación de RUNX1 , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas
11.
J Pak Med Assoc ; 64(11): 1313-4, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25831654

RESUMEN

Pelizaeus Merzbacher's Disease is an inherited X-linked recessive trait. Males have the disease, while females are usually carriers. We report the case of a 6-years-old girl who had nystagmus since birth and later on developed head nodding. She started talking at one year and walking at 18 months. Then she developed regression of milestones, with speech impairment and inability to walk which progressively worsened. Before presenting she had a generalised seizure. Her parents were second cousins. Family history was unremarkable. On examination she was awake, alert, there was bilateral horizontal nystagmus. Cranial nerve examination was normal. There was spastic paraparesis with bilateral extensor plantar response. Magnetic resonance imaging of the brain showed classical features of diffuse hypomyelination characteristic of Pelizaeus Merzbacher's Disease for this age group.


Asunto(s)
Enfermedad de Pelizaeus-Merzbacher/diagnóstico , Niño , Femenino , Humanos , Imagen por Resonancia Magnética
12.
Pak J Pharm Sci ; 27(3): 597-600, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24811823

RESUMEN

To check the nutritional and mineral contents of four medicinal plants viz., Peganum hermla, Solanum nigrum, Mentha longifolia, Achryanthus aspera, which are used as medicine traditionally in Soon Valley Khushab, Pakistan. Proximate analysis of plant sample determined that protein (7.491%) and ash (22.79%) was highest in Mentha longifolia, carbohydrate (75.23%) in Peganum hermla, fats (12.595%) and moisture (6.82%) was highest in Achryanthus aspera. In comparative assessment of the various species, the results showed that Achryanthus aspera. is the most significant species having higher concentrations of fat, fibre values compared to the other species. Absorption Spectrometric method was used for the elemental analysis of essential elements such as Fe, Cd, Cu,Mn, Pb, Cr, Ni and Na in medicinal plants in different range.


Asunto(s)
Plantas Medicinales/química , Minerales/análisis , Pakistán
13.
STAR Protoc ; 5(3): 103163, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38941184

RESUMEN

Chromatin immunoprecipitation (ChIP) combined with sequencing has revolutionized our understanding of gene regulation; however, its application to frozen adipose tissue presents unique challenges due to the high levels of lipid content. Here, we present a protocol for ChIP of histone modifications in human frozen adipose tissue. We describe steps for tissue preparation, chromatin isolation, sonication, pre-clearing of chromatin, and immunoprecipitation. We then detail procedures for elution, crosslink reversal, chromatin purification, quality control, and library synthesis.

14.
Seizure ; 116: 74-80, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37574425

RESUMEN

BACKGROUND: Adequate glucose supply is essential for brain function, therefore hypoglycemic states may lead to seizures. Since blood glucose supply for brain is buffered by liver glycogen, an impairment of liver glycogen synthesis by mutations in the liver glycogen synthase gene (GYS2) might result in a substantial neurological involvement. Here, we describe the phenotypes of affected siblings of two families harboring biallelic mutations in GYS2. METHODS: Two suspected families - a multiplex Pakistani family (family A) with three affected siblings and a family of Moroccan origin (family B) with a single affected child who presented with seizures and reduced fasting blood glucose levels were genetically characterized. Whole exome sequencing (WES) was performed on the index patients, followed by Sanger sequencing-based segregation analyses on all available members of both families. RESULTS: The variant prioritization of WES and later Sanger sequencing confirmed three mutations in the GYS2 gene (12p12.1) consistent with an autosomal recessive pattern of inheritance. A homozygous splice acceptor site variant (NM_021957.3, c. 1646 -2A>G) segregated in family A. Two novel compound heterozygous variants (NM_021957.3: c.343G>A; p.Val115Met and NM_021957.3: c.875A>T; p.Glu292Val) were detected in family B, suggesting glycogen storage disorder. A special diet designed to avoid hypoglycemia, in addition to change of the anti-seizure medication led to reduction in seizure frequency. CONCLUSIONS: This study suggests that the seizures in patients initially diagnosed with epilepsy might be directly caused, or influenced by hypoglycemia due to pathogenic variants in the GYS2 gene.


Asunto(s)
Glucemia , Hipoglucemia , Niño , Humanos , Secuenciación del Exoma , Glucógeno Hepático , Mutación/genética
15.
Sci Rep ; 13(1): 12700, 2023 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-37543672

RESUMEN

Malaria parasites carry out fatty acid synthesis (FAS) in their apicoplast organelle via a bacterially related (type II) enzymatic pathway. In the vertebrate host, exoerythrocytic Plasmodium stages rely on FAS, whereas intraerythrocytic stages depend on scavenging FA from their environment. In the mosquito, P. falciparum oocysts express and rely on FAS enzymes for sporozoite formation, but P. yoelii oocysts do not express, nor depend on, FAS enzymes and thus rely on FA scavenging to support sporogony. In P. berghei, FAS enzymes are similarly expendable for sporogony, indicating it conforms to the P. yoelii scenario. We show here that P. berghei, unexpectedly, expresses FAS enzymes throughout oocyst development. These findings indicate that P. berghei can employ FAS alongside FA scavenging to maximise sporogony and transmission, and is more similar to P. falciparum than previously assumed with respect to FA acquisition by the oocyst. The ability of oocysts to switch between FAS and scavenging could be an important factor in the non-competitive relationship of resource exploitation between Plasmodium parasites and their mosquito vectors, which shapes parasite virulence both in the insect and vertebrate.


Asunto(s)
Anopheles , Malaria Falciparum , Animales , Oocistos/metabolismo , Plasmodium berghei , Mosquitos Vectores , Malaria Falciparum/metabolismo , Anopheles/parasitología , Ácidos Grasos/metabolismo , Proteínas Protozoarias/metabolismo
16.
Front Ecol Evol ; 112023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37581102

RESUMEN

Membrane-located NAD(P) transhydrogenase (NTH) catalyses reversible hydride ion transfer between NAD(H) and NADP(H), simultaneously translocating a proton across the membrane. The enzyme is structurally conserved across prokaryotes and eukaryotes. In heterotrophic bacteria NTH proteins reside in the cytoplasmic membrane, whereas in animals they localise in the mitochondrial inner membrane. Eukaryotic NTH proteins exists in two distinct configurations (isoforms) and have non-mitochondrial functions in unicellular eukaryotes like Plasmodium, the causative agent of malaria. In this study, we carried out a systematic analysis of nth genes across eukaryotic life to determine its prevalence and distribution of isoforms. The results reveal that NTH is found across all major lineages, but that some organisms, notably plants, lack nth genes altogether. Isoform distribution and phylogenetic analysis reveals different nth gene loss scenarios in apicomplexan lineages, which sheds new light on the evolution of the Piroplasmida and Eimeriidae.

17.
Sci Rep ; 13(1): 22222, 2023 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-38097730

RESUMEN

Plasmodium oocysts develop on the abluminal side of the mosquito midgut in relatively small numbers. Oocysts possess an extracellular cell wall-the capsule-to protect them from the insect's haemolymph environment. To further maximise transmission, each oocyst generates hundreds of sporozoites through an asexual multiplication step called sporogony. Completion of transmission requires sporozoite egress from the capsule (excystation), but this process remains poorly understood. In this study, we fused the parasite-encoded capsule protein Cap380 with green fluorescent protein in a transgenic P. berghei line, allowing live fluorescence imaging of capsules throughout sporogony and sporozoite excystation. The results show that capsules progressively weaken during sporulation ultimately resulting in sporozoite exit through small holes. Prior to formation of the holes, local thinning of the capsule was observed. Our findings support an excystation model based on local, rather than global, weakening of the capsule likely facilitated by local re-orientation of sporozoites and apical secretion.


Asunto(s)
Culicidae , Plasmodium , Animales , Oocistos/metabolismo , Esporozoítos/metabolismo , Plasmodium/metabolismo , Animales Modificados Genéticamente/metabolismo , Culicidae/metabolismo , Proteínas Protozoarias/metabolismo , Plasmodium berghei/metabolismo
18.
Heliyon ; 9(6): e16597, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37292351

RESUMEN

This article compares the operator splitting scheme to linearly stabilized splitting and semi-implicit Euler's schemes for the numerical solution of the Cahn-Hilliard equation. For the purpose of validation, the spinodal decomposition phenomena have been simulated. The efficacy of the three schemes has been demonstrated through numerical experiments. The computed results show that the schemes are conditionally stable. It has been observed that the operator splitting scheme is computationally more efficient.

19.
Genes (Basel) ; 14(5)2023 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-37239478

RESUMEN

Vitiligo is an autoimmune complex pigmentation disease characterized by non-pigmented patches on the surface of the skin that affect approximately 0.5-2% population worldwide. The exact etiology is still unknown; however, vitiligo is hypothesized to be a multifactorial and genetically heterogeneous condition. Therefore, the current study is designed to investigate the anthropometric presentation and genetic spectrum of vitiligo in fifteen consanguineous Pakistani families. The clinical evaluation of participating individuals revealed varying degrees of disease severity, with 23 years as the average age of disease onset. The majority of the affected individuals had non-segmental vitiligo (NSV). Whole exome sequencing analysis revealed clustering of rare variants of known vitiligo-associated genes. For instance, in the affected individuals of family VF-12, we identified three novel rare variants of PTPN22 (c.1108C>A), NRROS (c.197C>T) and HERC2 (c.10969G>A) genes. All three variants replaced evolutionarily conserved amino acid residues in encoded proteins, which are predicted to impact the ionic interactions in the secondary structure. Although various in silico algorithms predicted low effect sizes for these variants individually, the clustering of them in affected individuals increases the polygenic burden of risk alleles. To our knowledge, this is the first study that highlights the complex etiology of vitiligo and genetic heterogeneity in multiplex consanguineous Pakistani families.


Asunto(s)
Enfermedades Autoinmunes , Vitíligo , Humanos , Consanguinidad , Vitíligo/genética , Secuenciación del Exoma , Pakistán/epidemiología , Predisposición Genética a la Enfermedad , Enfermedades Autoinmunes/genética , Análisis por Conglomerados , Proteína Tirosina Fosfatasa no Receptora Tipo 22/genética
20.
Cell Rep Med ; 4(9): 101187, 2023 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-37659411

RESUMEN

The long-term clinical outcomes of severe obesity due to leptin signaling deficiency are unknown. We carry out a retrospective cross-sectional investigation of a large cohort of children with leptin (LEP), LEP receptor (LEPR), or melanocortin 4 receptor (MC4R) deficiency (n = 145) to evaluate the progression of the disease. The affected individuals undergo physical, clinical, and metabolic evaluations. We report a very high mortality in children with LEP (26%) or LEPR deficiency (9%), mainly due to severe pulmonary and gastrointestinal infections. In addition, 40% of surviving children with LEP or LEPR deficiency experience life-threatening episodes of lung or gastrointestinal infections. Although precision drugs are currently available for LEP and LEPR deficiencies, as yet, they are not accessible in Pakistan. An appreciation of the severe impact of LEP or LEPR deficiency on morbidity and early mortality, educational attainment, and the attendant stigmatization should spur efforts to deliver the available life-saving drugs to these children as a matter of urgency.


Asunto(s)
Leptina , Obesidad Mórbida , Niño , Humanos , Estudios Transversales , Morbilidad , Estudios Retrospectivos
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