Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 54
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Ophthalmology ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38866367

RESUMO

PURPOSE: To evaluate whether providing clinicians with an artificial intelligence (AI)-based vascular severity score (VSS) improves consistency in the diagnosis of plus disease in retinopathy of prematurity (ROP). DESIGN: Multireader diagnostic accuracy imaging study. PARTICIPANTS: Eleven ROP experts, 9 of whom had been in practice for 10 years or more. METHODS: RetCam (Natus Medical Incorporated) fundus images were obtained from premature infants during routine ROP screening as part of the Imaging and Informatics in ROP study between January 2012 and July 2020. From all available examinations, a subset of 150 eye examinations from 110 infants were selected for grading. An AI-based VSS was assigned to each set of images using the i-ROP DL system (Siloam Vision). The clinicians were asked to diagnose plus disease for each examination and to assign an estimated VSS (range, 1-9) at baseline, and then again 1 month later with AI-based VSS assistance. A reference standard diagnosis (RSD) was assigned to each eye examination from the Imaging and Informatics in ROP study based on 3 masked expert labels and the ophthalmoscopic diagnosis. MAIN OUTCOME MEASURES: Mean linearly weighted κ value for plus disease diagnosis compared with RSD. Area under the receiver operating characteristic curve (AUC) and area under the precision-recall curve (AUPR) for labels 1 through 9 compared with RSD for plus disease. RESULTS: Expert agreement improved significantly, from substantial (κ value, 0.69 [0.59, 0.75]) to near perfect (κ value, 0.81 [0.71, 0.86]), when AI-based VSS was integrated. Additionally, a significant improvement in plus disease discrimination was achieved as measured by mean AUC (from 0.94 [95% confidence interval (CI), 0.92-0.96] to 0.98 [95% CI, 0.96-0.99]; difference, 0.04 [95% CI, 0.01-0.06]) and AUPR (from 0.86 [95% CI, 0.81-0.90] to 0.95 [95% CI, 0.91-0.97]; difference, 0.09 [95% CI, 0.03-0.14]). CONCLUSIONS: Providing ROP clinicians with an AI-based measurement of vascular severity in ROP was associated with both improved plus disease diagnosis and improved continuous severity labeling as compared with an RSD for plus disease. If implemented in practice, AI-based VSS could reduce interobserver variability and could standardize treatment for infants with ROP. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

2.
J Vector Borne Dis ; 61(1): 81-89, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38648409

RESUMO

BACKGROUND OBJECTIVES: Malaria due to Plasmodium falciparum (Pf) remains a major public threat in India. Artemisinin-based combination therapy (ACT) has been the country's first-line drug for uncomplicated Pf malaria. In 2013-2014, Artesunate plus sulfadoxine (AS+SP) was replaced by Artemether Lumefantrine (AL) as the first- line antimalarial in North East (NE) states of the country which are endemic for Pf malaria. Regular monitoring of antimalarial drugs is of utmost importance to achieve the goal of elimination. This study aimed to assess the efficacy and safety of ACT for treating uncomplicated Pf malaria in the NE states of India. METHODS: A prospective study of 28-day follow-up was conducted to monitor the efficacy and safety of AL from 2018-2019 in four districts, Udalgiri, Meghalaya, Lawngtlai, and Dhalai of NE, India. The clinical and parasitological response and the polymorphism analysis of the Pfdhps, P/dhfr, and Pfkelch 13 gene were evaluated. RESULTS: A total of 234 patients were enrolled in the study out of 216 patients who completed the follow-up to 28 days. One-hundred percent adequate clinical and parasitological responses (ACPR) were observed with polymerase chain reaction (PCR) correction. The genotype results suggest no recrudescence in the treatment-failure patients. The classical single nucleotide polymorphisms (SNP) in the Pfdhfr gene was S108N (94.9%), followed by C59R (91.5%), whereas, in the Pfdhps gene, the common SNP was A437G (79.6%), followed by S3436A. No associated or validated mutations were found in the propeller region of the PfKelch13 gene. INTERPRETATION CONCLUSION: AL was efficacious and safe in uncomplicated P. falciparum malaria in North East India. In contrast, mutations in the genes responsible for sulfadoxine and pyrimethamine resistance have been fixed in northeast India's population.


Assuntos
Antimaláricos , Artemisininas , Quimioterapia Combinada , Malária Falciparum , Plasmodium falciparum , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Índia , Humanos , Artemisininas/uso terapêutico , Artemisininas/efeitos adversos , Antimaláricos/uso terapêutico , Antimaláricos/administração & dosagem , Antimaláricos/efeitos adversos , Feminino , Masculino , Plasmodium falciparum/genética , Plasmodium falciparum/efeitos dos fármacos , Estudos Prospectivos , Adulto , Adulto Jovem , Adolescente , Pessoa de Meia-Idade , Resultado do Tratamento , Criança , Pré-Escolar , Combinação Arteméter e Lumefantrina/uso terapêutico , Sulfadoxina/uso terapêutico , Combinação de Medicamentos
3.
Indian J Med Res ; 157(1): 23-29, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37040223

RESUMO

Background & objectives: India targets malaria elimination by 2030 in a phased manner, so malaria's assured diagnosis is crucial. Introduction of rapid diagnostic kits in India in 2010 has revolutionized malaria surveillance. The storage temperature of rapid diagnostic tests (RDTs), kit components and handling in transportations impact the results of RDTs. Therefore, quality assurance (QA) is required before it reaches end-users. The Indian Council of Medical Research-National Institute of Malaria Research (ICMR-NIMR) has a World Health Organization (WHO) recognized lot-testing laboratory facility to assure the quality of RDTs. Methods: The ICMR-NIMR receives RDTs from different manufacturing companies as well as various agencies such as National and State Programmes and Central Medical Services Society. The WHO standard protocol is followed to conduct all the tests, including long-term and post-dispatch testing. Results: A total of 323 lots tested during January 2014-March 2021 were received from different agencies. Amongst them, 299 lots passed the quality of test and 24 failed. In long-term testing, 179 lots were tested and only nine failed. A total of 7741 RDTs were received from end-users for post-dispatch testing of which 7540 qualified the QA test with a score of 97.4 per cent. Interpretation & conclusions: RDTs received for quality testing showed compliance with QA evaluation of malaria RDTs based on the protocol recommended by the WHO. However, continuous monitoring of the quality of RDTs is required under QA programme. Quality-assured RDTs have a major role, especially in areas where low parasitaemia of parasites persists.


Assuntos
Testes Diagnósticos de Rotina , Malária , Humanos , Testes Diagnósticos de Rotina/métodos , Malária/diagnóstico , Testes de Diagnóstico Rápido , Índia , Comércio
4.
J Vector Borne Dis ; 60(2): 200-206, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37417170

RESUMO

BACKGROUND & OBJECTIVES: The highly sensitive method for a true understanding of malaria prevalence is of utmost importance for India's elimination strategy. The PCR reaction type with rapid detection, cost-effectiveness, and less workforce should be preferable. Multiplex PCR type accomplishes the present requirement by saving time and resources to find true surveillance data for malaria, especially in low-parasitemia/asymptomatic groups or populations. METHODS: The present study focuses on designing multiplex PCR (mPCR) to detect simultaneously Plasmodium genus (PAN) and two common Plasmodium species found in India. It is compared to standard nested PCR on 195 clinical samples to diagnose malaria. The mPCR was designed with a minimum number of primers, leading to less clogging and effective and enhanced detection. It contains one common reverse primer and three forward primers amplifying three targeted genes corresponding to P. falciparum, P. vivax, and Plasmodium genus. RESULTS: The sensitivity and specificity for mPCR were 94.06 and 95.74, respectively. The limit of detection for mPCR was 0.1 parasites/µl. The study has shown a ROC curve area for the mPCR of 0.949 for Plasmodium genus and P. falciparum and 0.897 for P. vivax with standard nPCR. INTERPRETATION & CONCLUSION: The mPCR is rapid in detecting species together, cost-effective, and requires fewer human resources than the standard nPCR. Therefore, the mPCR can be used as an alternative technique for the higher sensitive detection of the malaria parasite. It could also become a vital tool for determining malaria prevalence, facilitating the application of the most effective measures.


Assuntos
Malária Falciparum , Malária Vivax , Malária , Plasmodium , Humanos , Reação em Cadeia da Polimerase Multiplex/métodos , Plasmodium falciparum/genética , Plasmodium vivax/genética , Malária/diagnóstico , Malária/epidemiologia , Malária/parasitologia , Malária Falciparum/diagnóstico , Malária Vivax/diagnóstico , Malária Vivax/epidemiologia , Malária Vivax/parasitologia , Plasmodium/genética , Sensibilidade e Especificidade
5.
BMC Ophthalmol ; 22(1): 100, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35246073

RESUMO

BACKGROUND: CHARGE syndrome is a relatively common cause of deafness and blindness resulting from failure to form the primordia of specific organs due to deficient contribution of neural crest cell derivatives. The majority of CHARGE syndrome cases are caused by heterozygous mutations in CHD7 on chromosome 8q21. Those with CHARGE syndrome without CHD7 mutation typically do not have an identified genetic defect. 7q11.23 duplication syndrome is associated with mild facial dysmorphism, heart defects, language delay, and autism spectrum disorder. In the current literature, 7q11.23 duplication has not been associated with CHARGE syndrome, retinochoroidal colobomas, or significant ear abnormalities. CASE PRESENTATION: We describe a patient with 7q11.23 duplication syndrome and clinical CHARGE syndrome with no variant in CHARGE-associated genes. CONCLUSIONS: This case highlights the still incomplete understanding of the pathogenesis of CHARGE syndrome and raises the possibility of a dose-sensitive effect of genes in the 7q11.23 critical region on neural crest differentiation and fate.


Assuntos
Transtorno do Espectro Autista , Síndrome CHARGE , Coloboma , Síndrome CHARGE/complicações , Síndrome CHARGE/diagnóstico , Síndrome CHARGE/genética , Coloboma/diagnóstico , Coloboma/genética , Proteínas de Ligação a DNA/genética , Humanos , Mutação
6.
Ophthalmic Res ; 65(2): 229-236, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33113546

RESUMO

PURPOSE: Retinopathy of prematurity (ROP) is considered a disease of the inner retina; however, there is increasing evidence that demonstrates choroidal vasculature loss in ROP, leading to degeneration of outer retinal function and visual deterioration. Central choroidal thinning is noted in children with history of ROP using optical coherence tomography imaging. This study characterizes the presence and persistence of choroidal loss angiographically in eyes of infants treated with intravitreal bevacizumab (IVB) for stage 3 ROP. METHODS: The fluorescein angiography (FA) images of 62 eyes of 31 infants treated with IVB monotherapy were retrospectively reviewed. The eyes with good quality early-, mid-, and late-phase imaging were included in this study. The presence of choroidal hypofluoresence involving the central and or peripheral retina was noted. In infants with multiple FAs, serial FAs were analyzed for persistence of choroidal hypofluorescence. RESULTS: The mean age and birth weight of infants was 24.4 weeks post-menstrual age and 683 g, respectively. All infants received IVB monotherapy. Twenty-four of 62 angiography images of sufficient quality reviewed showed the presence of choroidal hypofluorescence involving central and peripheral lobular loss in the early phase and its persistence into mid- and late phases. Twelve eyes demonstrated persistent choroidal loss on sequential FA until 3 years chronological age. CONCLUSIONS: The study demonstrates the presence of choroidal vascular loss angiographically both central and peripheral fundus in infants with ROP. It highlights the critical role of choroidal involution in outer retinal function that could affect visual outcomes.


Assuntos
Retinopatia da Prematuridade , Inibidores da Angiogênese/uso terapêutico , Bevacizumab/uso terapêutico , Angiofluoresceinografia/métodos , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Injeções Intravítreas , Fotocoagulação a Laser , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/tratamento farmacológico , Estudos Retrospectivos
7.
Korean J Parasitol ; 60(4): 295-299, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36041492

RESUMO

Malaria elimination and control require prompt and accurate diagnosis for treatment plan. Since microscopy and rapid diagnostic test (RDT) are not sensitive particularly for diagnosing low parasitemia, highly sensitive diagnostic tools are required for accurate treatment. Molecular diagnosis of malaria is commonly carried out by nested polymerase chain reaction (PCR) targeting 18S rRNA gene, while this technique involves long turnaround time and multiple steps leading to false positive results. To overcome these drawbacks, we compared highly sensitive cytochrome oxidase gene-based single-step multiplex reaction with 18S rRNA nested PCR. Cytochrome oxidase (cox) genes of P. falciparum (cox-III) and P. vivax (cox-I) were compared with 18S rRNA gene nested PCR and microscopy. Cox gene multiplex PCR was found to be highly specific and sensitive, enhancing the detection limit of mixed infections. Cox gene multiplex PCR showed a sensitivity of 100% and a specificity of 97%. This approach can be used as an alternative diagnostic method as it offers higher diagnostic performance and is amenable to high throughput scaling up for a larger sample size at low cost.


Assuntos
Malária Falciparum , Malária Vivax , Malária , DNA de Protozoário/análise , DNA de Protozoário/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Humanos , Malária/diagnóstico , Malária Falciparum/diagnóstico , Malária Vivax/diagnóstico , Reação em Cadeia da Polimerase Multiplex/métodos , Plasmodium falciparum/genética , RNA Ribossômico 18S/genética , Sensibilidade e Especificidade
8.
Ophthalmic Res ; 64(1): 91-98, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32535604

RESUMO

INTRODUCTION: Bevacizumab and ranibizumab, which are anti-vascular endothelial growth factor (VEGF) medications, are used frequently in the treatment for retinopathy of prematurity (ROP) in infants. Aflibercept, or VEGF Trap, has been used anecdotally, but translation and clinical studies are lacking. OBJECTIVE: This study investigates the efficacy of aflibercept at reducing areas of non-perfused retina and studies its effect on normal angiogenesis in the oxygen-induced retinopathy mouse model of ROP. METHODS: C57BL/6 J mice were assigned to room air control (n = 21 eyes) or hyperoxia with 75% oxygen (n = 84 eyes). The hyperoxic mice were assigned to 1 of 3 groups: 0 ng (n = 14 eyes), 100 ng (n = 35 eyes), or 1,000 ng (n = 35 eyes) of intravitreal aflibercept administered on postnatal day 14. Eyes were enucleated at PN17 and PN25 postinjection. Retinas were stained with anti-collagen IV antibody and photographed with microscopy. Areas of perfused and non-perfused retina were quantified using ImageJ software. Statistical comparisons were made using ANOVA with Tukey post hoc comparisons. RESULTS: At PN17, there was no significant difference in the area of non-perfused retina between the hyperoxic control and the 100 and 1,000 ng aflibercept groups. At PN25, the 100 ng (p < 0.05) and 1,000 ng (p = 0.008) treatment groups displayed less non-perfusion compared to hyperoxic controls. At the 1,000 ng dose, there was increased non-perfusion compared to the 100 ng dose (p = 0.02). There was reduced non-perfusion by PN25 compared to PN17 for the 100 ng group (p < 0.05), with no difference in the 1,000 ng group. CONCLUSIONS: The study shows that the area of non-perfused retina decreases effectively with aflibercept at PN25 with 100 ng dosage. With the 1,000 ng dosage, there is an inhibition of the physiologic angiogenesis with a higher area of non-perfused retina.


Assuntos
Receptores de Fatores de Crescimento do Endotélio Vascular/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Retina/fisiopatologia , Retinopatia da Prematuridade/tratamento farmacológico , Acuidade Visual , Inibidores da Angiogênese/administração & dosagem , Animais , Modelos Animais de Doenças , Injeções Intravítreas , Camundongos , Camundongos Endogâmicos C57BL , Oxigênio/toxicidade , Retina/efeitos dos fármacos , Retinopatia da Prematuridade/induzido quimicamente , Retinopatia da Prematuridade/fisiopatologia , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
9.
BMC Bioinformatics ; 21(1): 466, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33076816

RESUMO

BACKGROUND: Homology based methods are one of the most important and widely used approaches for functional annotation of high-throughput microbial genome data. A major limitation of these methods is the absence of well-characterized sequences for certain functions. The non-homology methods based on the context and the interactions of a protein are very useful for identifying missing metabolic activities and functional annotation in the absence of significant sequence similarity. In the current work, we employ both homology and context-based methods, incrementally, to identify local holes and chokepoints, whose presence in the Mycobacterium tuberculosis genome is indicated based on its interaction with known proteins in a metabolic network context, but have not been annotated. We have developed two computational procedures using network theory to identify orphan enzymes ('Hole finding protocol') coupled with the identification of candidate proteins for the predicted orphan enzyme ('Hole filling protocol'). We propose an integrated interaction score based on scores from the STRING database to identify candidate protein sequences for the orphan enzymes from M. tuberculosis, as a case study, which are most likely to perform the missing function. RESULTS: The application of an automated homology-based enzyme identification protocol, ModEnzA, on M. tuberculosis genome yielded 56 novel enzyme predictions. We further predicted 74 putative local holes, 6 choke points, and 3 high confidence local holes in the genome using 'Hole finding protocol'. The 'Hole-filling protocol' was validated on the E. coli genome using artificial in-silico enzyme knockouts where our method showed 25% increased accuracy, compared to other methods, in assigning the correct sequence for the knocked-out enzyme amongst the top 10 ranks. The method was further validated on 8 additional genomes. CONCLUSIONS: We have developed methods that can be generalized to augment homology-based annotation to identify missing enzyme coding genes and to predict a candidate protein for them. For pathogens such as M. tuberculosis, this work holds significance in terms of increasing the protein repertoire and thereby, the potential for identifying novel drug targets.


Assuntos
Proteínas de Bactérias/genética , Biologia Computacional/métodos , Enzimas/genética , Mycobacterium tuberculosis/enzimologia , Homologia de Sequência de Aminoácidos , Sequência de Aminoácidos , Bases de Dados Factuais , Escherichia coli/enzimologia , Genoma Bacteriano , Anotação de Sequência Molecular
10.
BMC Genomics ; 20(1): 374, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088369

RESUMO

BACKGROUND: Phomafungin is a recently reported broad spectrum antifungal compound but its biosynthetic pathway is unknown. We combed publicly available Phoma genomes but failed to find any putative biosynthetic gene cluster that could account for its biosynthesis. RESULTS: Therefore, we sequenced the genome of one of our Phoma strains (F3723) previously identified as having antifungal activity in a high-throughput screen. We found a biosynthetic gene cluster that was predicted to synthesize a cyclic lipodepsipeptide that differs in the amino acid composition compared to Phomafungin. Antifungal activity guided isolation yielded a new compound, BII-Rafflesfungin, the structure of which was determined. CONCLUSIONS: We describe the NRPS-t1PKS cluster 'BIIRfg' compatible with the synthesis of the cyclic lipodepsipeptide BII-Rafflesfungin [HMHDA-L-Ala-L-Glu-L-Asn-L-Ser-L-Ser-D-Ser-D-allo-Thr-Gly]. We report new Stachelhaus codes for Ala, Glu, Asn, Ser, Thr, and Gly. We propose a mechanism for BII-Rafflesfungin biosynthesis, which involves the formation of the lipid part by BIIRfg_PKS followed by activation and transfer of the lipid chain by a predicted AMP-ligase on to the first PCP domain of the BIIRfg_NRPS gene.


Assuntos
Antifúngicos/química , Depsipeptídeos/química , Proteínas Fúngicas/genética , Saccharomycetales/genética , Sequência de Aminoácidos , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Vias Biossintéticas , Depsipeptídeos/biossíntese , Depsipeptídeos/farmacologia , Genômica , Estrutura Molecular , Família Multigênica , Saccharomycetales/metabolismo , Sequenciamento Completo do Genoma
11.
Proteomics ; 18(21-22): e1800093, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30265449

RESUMO

The mentioning of gene names in the body of the scientific literature 1901-2017 and their fractional counting is used as a proxy to assess the level of biological function discovery. A literature score of one has been defined as full publication equivalent (FPE), the amount of literature necessary to achieve one publication solely dedicated to a gene. It has been found that less than 5000 human genes have each at least 100 FPEs in the available literature corpus. This group of elite genes (4817 protein-coding genes, 119 non-coding RNAs) attracts the overwhelming majority of the scientific literature about genes. Yet, thousands of proteins have never been mentioned at all, ≈2000 further proteins have not even one FPE of literature and, for ≈4600 additional proteins, the FPE count is below 10. The protein function discovery rate measured as numbers of proteins first mentioned or crossing a threshold of accumulated FPEs in a given year has grown until 2000 but is in decline thereafter. This drop is partially offset by function discoveries for non-coding RNAs. The full human genome sequencing does not boost the function discovery rate. Since 2000, the fastest growing group in the literature is that with at least 500 FPEs per gene.


Assuntos
Genoma Humano/genética , Proteínas/genética , Humanos
12.
Protein Expr Purif ; 111: 23-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25782739

RESUMO

Mycobacterium tuberculosis (Mtb) is the causal agent of tuberculosis, the second largest infectious disease. With the rise of multi-drug resistant strains of M. tuberculosis, serious challenge lies ahead of us in treating the disease. The availability of complete genome sequence of Mtb has improved the scope for identifying new proteins that would not only further our understanding of biology of the organism but could also serve to discover new drug targets. In this study, Rv2345, a hypothetical membrane protein of M. tuberculosis H37Rv, which is reported to be a putative ortholog of ZipA cell division protein has been assigned function through functional annotation using bioinformatics tools followed by experimental validation. Sequence analysis showed Rv2345 to have a TPM domain at its N-terminal region and predicted it to have phosphatase activity. The TPM domain containing region of Rv2345 was cloned and expressed using pET28a vector in Escherichia coli and purified by Nickel affinity chromatography. The purified TPM domain was tested in vitro and our results confirmed it to have phosphatase activity. The enzyme activity was first checked and optimized with pNPP as substrate, followed by using ATP, which was also found to be used as substrate by the purified protein. Hence sequence analysis followed by in vitro studies characterizes TPM domain of Rv2345 to contain phosphatase activity.


Assuntos
Proteínas de Bactérias/química , Proteínas de Membrana/química , Mycobacterium tuberculosis/enzimologia , Monoéster Fosfórico Hidrolases/química , Proteínas de Bactérias/genética , Proteínas de Membrana/genética , Mycobacterium tuberculosis/genética , Monoéster Fosfórico Hidrolases/genética
13.
Biol Direct ; 18(1): 46, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37574542

RESUMO

BACKGROUND: Although the genome of Saccharomyces cerevisiae (S. cerevisiae) was the first one of a eukaryote organism that was fully sequenced (in 1996), a complete understanding of the potential of encoded biomolecular mechanisms has not yet been achieved. Here, we wish to quantify how far the goal of a full list of S. cerevisiae gene functions still is. RESULTS: The scientific literature about S. cerevisiae protein-coding genes has been mapped onto the yeast genome via the mentioning of names for genomic regions in scientific publications. The match was quantified with the ratio of a given gene name's occurrences to those of any gene names in the article. We find that ~ 230 elite genes with ≥ 75 full publication equivalents (FPEs, FPE = 1 is an idealized publication referring to just a single gene) command ~ 45% of all literature. At the same time, about two thirds of the genes (each with less than 10 FPEs) are described in just 12% of the literature (in average each such gene has just ~ 1.5% of the literature of an elite gene). About 600 genes have not been mentioned in any dedicated article. Compared with other groups of genes, the literature growth rates were highest for uncharacterized or understudied genes until late nineties of the twentieth century. Yet, these growth rates deteriorated and became negative thereafter. Thus, yeast function discovery for previously uncharacterized genes has returned to the level of ~ 1980. At the same time, literature for anyhow well-studied genes (with a threshold T10 (≥ 10 FPEs) and higher) remains steadily growing. CONCLUSIONS: Did the early full genome sequencing of yeast boost gene function discovery? The data proves that the moment of publishing the full genome in reality coincides with the onset of decline of gene function discovery for previously uncharacterized genes. If the current status of literature about yeast molecular mechanisms can be extrapolated into the future, it will take about another ~ 50 years to complete the yeast gene function list. We found that a small group of scientific journals contributed extraordinarily to publishing early reports relevant to yeast gene function discoveries.


Assuntos
Genômica , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Sequência de Bases , Fenótipo
14.
Biol Direct ; 18(1): 7, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36855185

RESUMO

BACKGROUND: Although Escherichia coli (E. coli) is the most studied prokaryote organism in the history of life sciences, many molecular mechanisms and gene functions encoded in its genome remain to be discovered. This work aims at quantifying the illumination of the E. coli gene function space by the scientific literature and how close we are towards the goal of a complete list of E. coli gene functions. RESULTS: The scientific literature about E. coli protein-coding genes has been mapped onto the genome via the mentioning of names for genomic regions in scientific articles both for the case of the strain K-12 MG1655 as well as for the 95%-threshold softcore genome of 1324 E. coli strains with known complete genome. The article match was quantified with the ratio of a given gene name's occurrence to the mentioning of any gene names in the paper. The various genome regions have an extremely uneven literature coverage. A group of elite genes with ≥ 100 full publication equivalents (FPEs, FPE = 1 is an idealized publication devoted to just a single gene) attracts the lion share of the papers. For K-12, ~ 65% of the literature covers just 342 elite genes; for the softcore genome, ~ 68% of the FPEs is about only 342 elite gene families (GFs). We also find that most genes/GFs have at least one mentioning in a dedicated scientific article (with the exception of at least 137 protein-coding transcripts for K-12 and 26 GFs from the softcore genome). Whereas the literature growth rates were highest for uncharacterized or understudied genes until 2005-2010 compared with other groups of genes, they became negative thereafter. At the same time, literature for anyhow well-studied genes started to grow explosively with threshold T10 (≥ 10 FPEs). Typically, a body of ~ 20 actual articles generated over ~ 15 years of research effort was necessary to reach T10. Lineage-specific co-occurrence analysis of genes belonging to the accessory genome of E. coli together with genomic co-localization and sequence-analytic exploration hints previously completely uncharacterized genes yahV and yddL being associated with osmotic stress response/motility mechanisms. CONCLUSION: If the numbers of scientific articles about uncharacterized and understudied genes remain at least at present levels, full gene function lists for the strain K-12 MG1655 and the E. coli softcore genome are in reach within the next 25-30 years. Once the literature body for a gene crosses 10 FPEs, most of the critical fundamental research risk appears overcome and steady incremental research becomes possible.


Assuntos
Escherichia coli , Iluminação , Escherichia coli/genética , Genômica
15.
Comput Biol Med ; 165: 107433, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37660569

RESUMO

Glioblastoma multiforme (GBM) is the most aggressive form of brain tumor characterized by inter and intra-tumor heterogeneity and complex tumor microenvironment. To uncover the molecular targets in this milieu, we systematically identified immune and stromal interactions at the glial cell type level that leverages on RNA-sequencing data of GBM patients from The Cancer Genome Atlas. The perturbed genes between the high vs low immune and stromal scored patients were subjected to weighted gene co-expression network analysis to identify the glial cell type specific networks in immune and stromal infiltrated patients. The intramodular connectivity analysis identified the highly connected genes in each module. Combining it with univariable and multivariable prognostic analysis revealed common vital gene ITGB2, between the immune and stromal infiltrated patients enriched in microglia and newly formed oligodendrocytes. We found following unique hub genes in immune infiltrated patients; COL6A3 (microglia), ITGAM (oligodendrocyte precursor cells), TNFSF9 (microglia), and in stromal infiltrated patients, SERPINE1 (microglia) and THBS1 (newly formed oligodendrocytes, oligodendrocyte precursor cells). To validate these hub genes, we used external GBM patient single cell RNA-sequencing dataset and this identified ITGB2 to be significantly enriched in microglia, newly formed oligodendrocytes, T-cells, macrophages and adipocyte cell types in both immune and stromal datasets. The tumor infiltration analysis of ITGB2 showed that it is correlated with myeloid dendritic cells, macrophages, monocytes, neutrophils, B-cells, fibroblasts and adipocytes. Overall, the systematic screening of tumor microenvironment components at glial cell types uncovered ITGB2 as a potential target in primary GBM.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Cadeias beta de Integrinas , Humanos , Neoplasias Encefálicas/genética , Glioblastoma/genética , Macrófagos , Neuroglia , Microambiente Tumoral/genética , Cadeias beta de Integrinas/metabolismo
16.
Cureus ; 15(9): e45880, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37885499

RESUMO

Background Cardiovascular responses to exercise are essential indicators of cardiovascular health and fitness. Understanding how different types of exercise, such as lower-body and whole-body exercises, impact these responses is crucial for designing effective fitness programs and assessing cardiovascular function. Aim This study aimed to compare the cardiovascular response of young adults during lower-body exercise using a bicycle ergometer and whole-body exercise on a treadmill. Methods Thirty-two healthy young adults participated in this study. Each participant completed two exercise sessions on separate days: lower-body exercise on a bicycle ergometer with a fixed cadence of 60 rpm with a breaking resistance of 1.75 kg and whole-body exercise on a treadmill with a speed of 1.7 mph and a 10% grade. Heart rate (HR), systolic blood pressure (BP), and diastolic BP were measured at rest and immediately after a three-minute exercise. Data were analyzed using paired t-tests to compare the cardiovascular responses between the two exercise modalities. Results A total of 17 male and 15 female young adults with a mean age of 20.87±1.43 years participated in the study. The male and female participants had similar ages (p =0.56) and body mass indexes (p = 0.1). There was a higher HR (129.16±2.67 versus 150.87±3.23, p<0.0001) and systolic BP (127.29±2.34 versus 144.9±4.16, p<0.0001) and lower diastolic BP (68.97±2.41 versus 62.97±2.31, p<0.0001) in whole body exercise on treadmill compared to lower body exercise in bicycle ergometer. The effect size was large enough as Cohen's d was 7.33, 5.13, and 2.54 for HR, systolic BP, and diastolic BP, respectively. Conclusion In sedentary young adults, treadmill exercise led to higher HR, systolic BP, and lower diastolic BP than bicycle ergometer exercise. Increased muscle recruitment might result in higher energy expenditure, increasing the HR and systolic BP to deliver oxygen and nutrients to the working muscles. Further research is needed to understand the mechanisms and long-term implications for precise exercise recommendations and better cardiovascular health management.

17.
Clin Ther ; 45(1): 4-16, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36581528

RESUMO

PURPOSE: Premature infants, after anti-vascular endothelial growth factor injections for retinopathy of prematurity, have persistent peripheral avascular retina (PAR). PAR is ablated with laser; however, physiologic growth of the retinal vasculature in the long term has not been measured. The purposes of this study were to measure retinal vessel growth after treatment with intravitreal bevacizumab (IVB) for retinopathy of prematurity, using serial fluorescein angiography (FA), until age 3 years, and to assess the timing for providing laser ablation in PAR. METHODS: Data from an observational, longitudinal clinical study were collected. Angiographic images of eyes treated with IVB were included; imaging data from laser photocoagulation were excluded. All eyes underwent initial examination under general anesthesia with FA and photographic imaging. The retinal vessel length was measured from the temporal margin of the optic disc passing through the foveal center, and the lengths at subsequent FA were compared. To compare the changes in retinal vessel length over time in individual eyes, a paired-sample t test was performed. FINDINGS: FA images from 70 eyes (35 infants) treated with IVB were available. A total of 150 FA images were available for review; data from 125 images of good quality were used for analysis. The mean postmenstrual ages (PMAs) at first, second, third, and fourth FA were 66.2, 100.9, 135.1, and 180.7 weeks, respectively. The mean retinal vessel length was 14.177 mm at first FA and 13.199 mm at fourth FA (PMA range, 42...234 weeks). Retinal vascular lengths of individual eyes compared over time showed no statistically significant growth from the first FA to age 3 years. The changes in retinal vessel length from first to second FA were -0.117 ± 0.79 mm (p = 0.42; n = 30); from first to third FA, +0.060 ± 0.85 mm (p = 0.79; n = 15); and first to fourth FA, -0.404 ± 1.32 mm (p = 0.45; n = 7). IMPLICATIONS: Beyond 65 weeks' PMA, no meaningful retinal vascular growth occurred after IVB up to age 3 years, guiding the timing for physicians if laser photocoagulation is being considered. Future studies are needed to address retinal growth changes in the growing eyes of infants.


Assuntos
Inibidores da Angiogênese , Retinopatia da Prematuridade , Recém-Nascido , Lactente , Humanos , Pré-Escolar , Bevacizumab , Inibidores da Angiogênese/uso terapêutico , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/tratamento farmacológico , Injeções Intravítreas , Estudos Retrospectivos , Recém-Nascido Prematuro
18.
Bioorg Med Chem Lett ; 22(9): 3104-8, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22483392

RESUMO

Novel plumbagin hydrazonates were prepared, structurally characterized and evaluated for anti-proliferative activity against estrogen receptor-positive MCF-7 and triple negative MDA-MB-231 and MDA-MB-468 breast cancer cell lines which exhibited superior inhibitory activity than parent plumbagin compound. Molecular docking studies indicated that hydroxyl groups on plumbagin and hydrazonate side chain favor additional hydrogen bonding interactions with amino acid residues in p50-subunit of NF-κB protein and these compounds inhibited NF-κB expression which may be responsible for the enhanced anti-proliferative activity. These compounds were found to be more effective against triple negative breast cancer cells and might serve as a starting point for building future strategies against triple negative breast cancers which are known for their increased drug resistance and poor prognosis of breast cancer patients.


Assuntos
Antineoplásicos/síntese química , Neoplasias da Mama/tratamento farmacológico , Hidrazonas/química , Naftoquinonas/química , Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos , Sítios de Ligação , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Hidrazonas/farmacologia , Ligação de Hidrogênio , NF-kappa B/metabolismo , Ligação Proteica , Relação Estrutura-Atividade
19.
Comput Struct Biotechnol J ; 20: 90-106, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34976314

RESUMO

Glioblastoma multiforme persists to be an enigmatic distress in neuro-oncology. Its untethering capacity to thrive in a confined microenvironment, metastasize intracranially, and remain resistant to the systemic treatments, renders this tumour incurable. The glial cell type specificity in GBM remains exploratory. In our study, we aimed to address this problem by studying the GBM at the cell type level in the brain. The cellular makeup of this tumour is composed of genetically altered glial cells which include astrocyte, microglia, oligodendrocyte precursor cell, newly formed oligodendrocyte and myelinating oligodendrocyte. We extracted cell type-specific solid tumour as well as recurrent solid tumour glioma genes, and studied their functional networks and contribution towards gliomagenesis. We identified the principal transcription factors that are found to be regulating vital tumorigenic processes. We also assessed the protein-protein interaction networks at their domain level to get a more microscopic view of the structural and functional operations that transpire in these cells. This yielded the eminent protein regulators exhibiting their regulation in signaling pathways. Overall, our study unveiled regulatory mechanisms in glioma cell types that can be targeted for a more efficient glioma therapy.

20.
Comput Struct Biotechnol J ; 20: 4025-4039, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35983230

RESUMO

Colorectal cancer (CRC) is a significant contributor to cancer-related deaths caused by an unhealthy lifestyle. Multiple studies reveal that viruses are involved in colorectal tumorigenesis. The viruses such as Human Cytomegalovirus (HCMV), Human papillomaviruses (HPV16 & HPV18), and John Cunningham virus (JCV) are known to cause colorectal cancer. The molecular mechanisms of cancer genesis and maintenance shared by these viruses remain unclear. We analysed the virus-host networks and connected them with colorectal cancer proteome datasets and extracted the core shared interactions in the virus-host CRC network. Our network topology analysis identified prominent virus proteins RL6 (HCMV), VE6 (HPV16 and HPV18), and Large T antigen (JCV). Sequence analysis uncovered short linear motifs (SLiMs) in each viral target. We used these targets to identify the antiviral drugs through a structure-based virtual screening approach. This analysis highlighted that temsavir, pimodivir, famotine, and bictegravir bind to each virus protein target, respectively. We also assessed the effect of drug binding using molecular dynamic simulations, which shed light on the modulatory effect of drug molecules on SLiM regions in viral targets. Hence, our systematic screening of virus-host networks revealed viral targets, which could be crucial for cancer therapy.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA