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1.
Arch Gynecol Obstet ; 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39235471

RESUMEN

PURPOSE: In recent years, fat grafting has gained importance as a valuable technique in breast surgery. As a breast center that has embraced this approach, we aimed to investigate the indications and complications of fat grafting. METHODS: In this retrospective study, we examined a total of 263 lipofilling treatments on 121 patients. Five groups were identified: the reconstruction group (72.7%), consisting of 24.8% autologous and 38% implant-based reconstructions after cancer, and correction of the tuberous breasts (10.7%). An almost equivalent group (10.7%), consisted of patients treated for cosmetic reasons. Patients after breast-conserving therapy amounted to 16.5%. Twenty patients (16.5%) were treated to alleviate pain. RESULTS: No major complications, and no cancer recurrence or metastasis were observed. One case of infection occurred at the injection site (infection rate: 0.38%). ANOVA showed statistically significant results for age (p < 0.001) and mean fat volume (p = 0.001). Posthoc analysis showed that the mean age of the tuberous group (21 years) was significantly smaller compared to all other categories (p < 0.001). Post-hoc analysis for fat volume indicated that the mean value for the cosmetic category (447.08 cc) was significantly greater than that of the breast-conserving and implant reconstruction categories (p = 0.009 and p = 0.030, respectively), while not significantly different from the tuberous and autologous reconstruction categories (p = 0.928 and p = 0.648, respectively). CONCLUSIONS: Lipofilling has proven a valuable adjunct in reconstructive and aesthetic breast surgery with a low complication profile. The versatility of this low-cost technique and the low rate of complications make it a powerful asset of modern breast centers.

2.
Aesthetic Plast Surg ; 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760537

RESUMEN

BACKGROUND: The correction of tuberous breast deformity with fat grafting has gained popularity in recent years, but it remains unclear whether this new technique can produce patient satisfaction levels comparable to those achieved with implant-based correction. METHODS: This study aimed to compare patients' satisfaction and quality of life using the BREAST-Q questionnaire after correction of tuberous breast deformity with fat grafting and implants. Twenty-four patients (36 breasts) were included in our study. Thirteen patients (15 breasts) had a correction with lipofilling (mean 2.67 interventions) and 11 patients (21 breasts) had an implant-based correction (mean 1 intervention). RESULTS: Both fat and implant treatments showed statistically significant improvements in breast satisfaction (p value=0.001, 0.002, respectively), psychosocial (p value=0.003, 0.003, respectively), and sexual satisfaction (p value=0.008, 0.002, respectively) between the pre-treatment and post-treatment stages. However, the only statistically significant differences between the treatments were observed in the physical condition pre-treatment (p value=0.008) and sexual condition post-treatment (p value=0.030). The outcome of both treatments was not statistically different. Furthermore, the outcome exhibited a statistically significant positive linear relationship with breast satisfaction for both treatments. CONCLUSIONS: This study suggests that lipofilling can achieve breast and outcome satisfaction comparable to that of implants, although this parity in results comes at the cost of more interventions. These preliminary results lend support to the notion that, as surgeons have access to two equally effective techniques, it is crucial to provide appropriate guidance to patients to ensure their satisfaction. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

3.
Sensors (Basel) ; 23(5)2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36904866

RESUMEN

Wireless Local Area Networks (WLANs) have become an increasingly popular mode of communication and networking, with a wide range of applications in various fields. However, the increasing popularity of WLANs has also led to an increase in security threats, including denial of service (DoS) attacks. In this study, management-frames-based DoS attacks, in which the attacker floods the network with management frames, are particularly concerning as they can cause widespread disruptions in the network. Attacks known as denial of service (DoS) can target wireless LANs. None of the wireless security mechanisms in use today contemplate defence against them. At the MAC layer, there are multiple vulnerabilities that can be exploited to launch DoS attacks. This paper focuses on designing and developing an artificial neural network (NN) scheme for detecting management-frames-based DoS attacks. The proposed scheme aims to effectively detect fake de-authentication/disassociation frames and improve network performance by avoiding communication interruption caused by such attacks. The proposed NN scheme leverages machine learning techniques to analyse patterns and features in the management frames exchanged between wireless devices. By training the NN, the system can learn to accurately detect potential DoS attacks. This approach offers a more sophisticated and effective solution to the problem of DoS attacks in wireless LANs and has the potential to significantly enhance the security and reliability of these networks. According to the experimental results, the proposed technique exhibits higher effectiveness in detection compared to existing methods, as evidenced by a significantly increased true positive rate and a decreased false positive rate.

4.
Int J Mol Sci ; 24(15)2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37569792

RESUMEN

Sixteen new thalidomide analogs were synthesized. The new candidates showed potent in vitro antiproliferative activities against three human cancer cell lines, namely hepatocellular carcinoma (HepG-2), prostate cancer (PC3), and breast cancer (MCF-7). It was found that compounds XII, XIIIa, XIIIb, XIIIc, XIIId, XIVa, XIVb, and XIVc showed IC50 values ranging from 2.03 to 13.39 µg/mL, exhibiting higher activities than thalidomide against all tested cancer cell lines. Compound XIIIa was the most potent candidate, with an IC50 of 2.03 ± 0.11, 2.51 ± 0.2, and 0.82 ± 0.02 µg/mL compared to 11.26 ± 0.54, 14.58 ± 0.57, and 16.87 ± 0.7 µg/mL for thalidomide against HepG-2, PC3, and MCF-7 cells, respectively. Furthermore, compound XIVc reduced the expression of NFκB P65 levels in HepG-2 cells from 278.1 pg/mL to 63.1 pg/mL compared to 110.5 pg/mL for thalidomide. Moreover, compound XIVc induced an eightfold increase in caspase-8 levels with a simultaneous decrease in TNF-α and VEGF levels in HepG-2 cells. Additionally, compound XIVc induced apoptosis and cell cycle arrest. Our results reveal that the new candidates are potential anticancer candidates, particularly XIIIa and XIVc. Consequently, they should be considered for further evaluation for the development of new anticancer drugs.


Asunto(s)
Antineoplásicos , Talidomida , Masculino , Humanos , Talidomida/farmacología , Antineoplásicos/farmacología , Relación Estructura-Actividad , Quinazolinas/farmacología , Factor A de Crecimiento Endotelial Vascular/farmacología , Adyuvantes Inmunológicos/farmacología , Células MCF-7 , Factores Inmunológicos/farmacología , Proliferación Celular , Ensayos de Selección de Medicamentos Antitumorales , Estructura Molecular , Apoptosis , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga
5.
J Med Virol ; 94(8): 3685-3697, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35415939

RESUMEN

Malaria and coronavirus disease 2019 (COVID-19) share several characteristics that could lead to cross-infection, particularly in malaria-endemic areas. Early COVID-19 symptoms might be misdiagnosed for malaria in clinical settings. Also, both diseases can cause fatal complications. So, laboratory testing for both diseases was recommended by the World Health Organization. To study the clinical characteristics and outcomes of Adult Sudanese patients with COVID-19 and malaria coinfection. This retrospective cross-sectional study was conducted from January 2021 to October 2021 in Wad Medani. Total coverage of all Sudanese patients above 18 years old with a confirmed diagnosis of coinfection with COVID-19 and malaria was included, and data were collected using a data collection sheet. Data were analyzed using R software version 4.0.2. Data were described and presented as mean, standard deviation, and number (percentage). To find associated factors with in-hospital outcome, χ2 test, fisher exact test, and independent t test or Wilcoxon rank-sum test were used. In this study, 156 participants were diagnosed with COVID-19 and malaria coinfection. Most of them were between 60 and 70 years (30.8%), the majority were males (59%). Shortness of breath (76.3%) and acute respiratory distress syndrome (35.3%) were the most common symptom and complications among coinfected patients, respectively. Ground glass opacity (n = 47/49, 95.9%) is the most common result for computed tomography scan. Atrial fibrillation was the most common abnormal electrocardiogram finding (n = 6/62, 9.7%). Overall mortality among all participants was (63/156, 40.4%). High mortality rate was found among the coinfected patients. More attention is needed towards fighting COVID-19 and malaria coinfection. There may be a link between malaria and COVID-19.


Asunto(s)
COVID-19 , Coinfección , Malaria , Adolescente , Adulto , COVID-19/complicaciones , COVID-19/diagnóstico , Coinfección/epidemiología , Estudios Transversales , Femenino , Humanos , Malaria/complicaciones , Malaria/diagnóstico , Malaria/epidemiología , Masculino , Estudios Retrospectivos , Sudán/epidemiología
6.
Arch Virol ; 167(9): 1773-1783, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35723757

RESUMEN

Currently, health authorities around the world are struggling to limit the spread of COVID-19. Since the beginning of the pandemic, social distancing has been the most important strategy used by most countries to control disease spread by flattening and elongating the epidemic curve. Another strategy, herd immunity, was also applied by some countries through relaxed control measures that allow the free spread of natural infection to build up solid immunity within the population. In 2021, COVID-19 vaccination was introduced with tremendous effort as a promising strategy for limiting the spread of disease. Therefore, in this review, we present the current knowledge about social distancing, herd immunity strategies, and aspects of their implementation to control the COVID-19 pandemic in the presence of the newly developed vaccines. Finally, we suggest a short-term option for controlling the pandemic during vaccine application.


Asunto(s)
COVID-19 , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Inmunidad Colectiva , Pandemias/prevención & control , Distanciamiento Físico , SARS-CoV-2
7.
J Enzyme Inhib Med Chem ; 37(1): 573-591, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35012403

RESUMEN

Based on quinazoline, quinoxaline, and nitrobenzene scaffolds and on pharmacophoric features of VEGFR-2 inhibitors, 17 novel compounds were designed and synthesised. VEGFR-2 IC50 values ranged from 60.00 to 123.85 nM for the new derivatives compared to 54.00 nM for sorafenib. Compounds 15a, 15b, and 15d showed IC50 from 17.39 to 47.10 µM against human cancer cell lines; hepatocellular carcinoma (HepG2), prostate cancer (PC3), and breast cancer (MCF-7). Meanwhile, the first in terms of VEGFR-2 inhibition was compound 15d which came second with regard to antitumor assay with IC50 = 24.10, 40.90, and 33.40 µM against aforementioned cell lines, respectively. Furthermore, Compound 15d increased apoptosis rate of HepG2 from 1.20 to 12.46% as it significantly increased levels of Caspase-3, BAX, and P53 from 49.6274, 40.62, and 42.84 to 561.427, 395.04, and 415.027 pg/mL, respectively. Moreover, 15d showed IC50 of 253 and 381 nM against HER2 and FGFR, respectively.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Simulación del Acoplamiento Molecular , Inhibidores de Proteínas Quinasas/farmacología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Nitrobencenos/síntesis química , Nitrobencenos/química , Nitrobencenos/farmacología , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Quinazolinas/síntesis química , Quinazolinas/química , Quinazolinas/farmacología , Quinoxalinas/síntesis química , Quinoxalinas/química , Quinoxalinas/farmacología , Relación Estructura-Actividad , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo
8.
Aesthetic Plast Surg ; 46(6): 2677-2688, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35804155

RESUMEN

BACKGROUND: Chronic pain after breast cancer surgery is affecting up to 60% of patients, causing significant morbidity to patients. Lately, fat grafting has been applied as a therapy for chronic neuropathic pain. METHODS: We report a series of eighteen patients, who were treated for pain after breast cancer surgery. Twelve patients had a breast conserving therapy, two a mastectomy and four an autologous flap-based reconstruction. While most presented with neuropathic pain, six patients had fat necrosis in their history. Most patients presented with severe pain (77%) and were treated with fat grafting sessions, performed by water-assisted liposuction. RESULTS: All patients responded to the interventions; the median number of fat grafting sessions was 2, the median duration of the interventions was 4 months, and the median follow-up period was 56.5 months. The median pain prior to the fat grafting procedure had an intensity of 8 (range 7-9) numeric rating scale points; after the first intervention, this was reduced to 4 (range 2.3-5.8); and after the second intervention, it was down to 2 (range 0.8-3.3). Patients with pain intensities of 4-5 had a good chance of achieving analgesia after one session. CONCLUSIONS: Fat grafting could be a new treatment modality for symptomatic fat necrosis: complete or partial suction of the necrosis and/or fat grafting around the necrosis to reduce inflammation and pain. Fat grafting proved a valuable tool, reducing pain or even achieving analgesia after breast cancer surgery presenting with a highly favorable risk-benefit ratio. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Asunto(s)
Neoplasias de la Mama , Necrosis Grasa , Neuralgia , Humanos , Femenino , Mastectomía/efectos adversos , Neoplasias de la Mama/cirugía , Necrosis Grasa/etiología , Necrosis Grasa/cirugía , Tejido Adiposo
9.
Molecules ; 27(15)2022 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-35956997

RESUMEN

This work is one of our efforts to discover potent anticancer agents. We modified the most promising derivative of our previous work concerned with the development of VEGFR-2 inhibitor candidates. Thirteen new compounds based on benzoxazole moiety were synthesized and evaluated against three human cancer cell lines, namely, breast cancer (MCF-7), colorectal carcinoma (HCT116), and hepatocellular carcinoma (HepG2). The synthesized compounds were also evaluated against VEGFR-2 kinase activity. The biological testing fallouts showed that compound 8d was more potent than standard sorafenib. Such compound showed IC50 values of 3.43, 2.79, and 2.43 µM against the aforementioned cancer cell lines, respectively, compared to IC50 values of 4.21, 5.30, and 3.40 µM reported for sorafenib. Compound 8d also was found to exert exceptional VEGFR-2 inhibition activity with an IC50 value of 0.0554 µM compared to sorafenib (0.0782 µM). In addition, compound 8h revealed excellent cytotoxic effects with IC50 values of 3.53, 2.94, and 2.76 µM against experienced cell lines, respectively. Furthermore, compounds 8a and 8e were found to inhibit VEGFR-2 kinase activity with IC50 values of 0.0579 and 0.0741 µM, exceeding that of sorafenib. Compound 8d showed a significant apoptotic effect and arrested the HepG2 cells at the pre-G1 phase. In addition, it exerted a significant inhibition for TNF-α (90.54%) and of IL-6 (92.19%) compared to dexamethasone (93.15%). The molecular docking studies showed that the binding pattern of the new compounds to VEGFR-2 kinase was similar to that of sorafenib.


Asunto(s)
Antineoplásicos , Receptor 2 de Factores de Crecimiento Endotelial Vascular , Antineoplásicos/química , Apoptosis , Benzoxazoles/química , Proliferación Celular , Diseño de Fármacos , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Inhibidores de Proteínas Quinasas/química , Sorafenib/farmacología , Relación Estructura-Actividad
10.
Bioorg Chem ; 109: 104695, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33647743

RESUMEN

Globally cancer is the second leading cause of death. So that this work is an attempt to develop new effective anti-cancer agents. In line with pharmacophoric features of VEGFR-2 kinase inhibitors, new nineteen quinazolin-4-one derivatives were designed, synthesized and biologically evaluated for their potential anticancer activity. All target compounds were evaluated in vitro for VEGFR-2 tyrosine kinase inhibition. Then, nine compounds of best results were further investigated by in vitro assay against three human cancer cell lines, namely HepG2, PC3 and MCF. N'-{2-](3-Ethyl-6-nitro-4-oxo-3,4-dihydroquinazoline-2-yl)thio[acetyl}benzohydrazide (36) was found to be the most potent candidate as it showed IC50 = 4.6 ± 0.06 µM against VEGFR-2 kinase. It also exhibited IC50 = 17.23 ± 1.5, 26.10 ± 2.2 and 30.85 ± 2.3 µg/mL against HepG2, PC3 and MCF, respectively. At the same time it showed IC50 = 145.93 ± 1.1 µg/mL against the normal human lung fibroblasts cell line (WI-38), indicating good selectivity index. Further investigation into HepG2 cell cycle showed the ability of compound 36 to induce apoptosis and arrest cell growth at G2/M phase. Moreover, docking studies demonstrated the ability of compound 36 to bind VEGFR-2 in a correct manner making three essential hydrogen bonds with the key residues Glu885, Asp1046 and Cys919. In sum, this work suggests that compound 36 can serve as a lead for development of effective anticancer agents targeting VEGFR-2.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Diseño de Fármacos , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Antineoplásicos/química , Línea Celular Tumoral , Citocromo P-450 CYP2D6/metabolismo , Inhibidores del Citocromo P-450 CYP2D6/química , Inhibidores del Citocromo P-450 CYP2D6/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Conformación Proteica
11.
Aesthetic Plast Surg ; 45(6): 2729-2741, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33864117

RESUMEN

BACKGROUND: In the surgical correction of tuberous breast deformity, implants and regional flaps play a prominent role. Lately, fat grafting has been used as an alternative, but there is evidence that patient satisfaction is higher after correction with implants compared with lipofilling. METHODS: We report a tuberous breasts correction series of ten cases, enrolled between 2015 and 2018. Percutaneous fasciotomies and fat grafting were performed by the Body-Jet technique. Analysis of outcomes was undertaken with BREAST-Q surveys. RESULTS: The breast satisfaction scores increased from 0 to 75 (p < 0.01), the psychological well-being scores from 20 to 70 (p < 0.01) and the sexual well-being scores from 18.5 to 58 (p = 0.02), while the physical well-being scores remained stable (from 68 to 63, p = 0.2). The median outcome satisfaction score was 86. CONCLUSION: Scores of patient-reported outcomes after lipofilling can reach and even exceed those of patients corrected with implants, at the cost of more interventions. Fat grafting is beginning to establish itself as a true alternative in the treatment of tuberous breast deformity in patients with the appropriate fat deposits. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine Ratings, please refer to Table of Contents or online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Anomalías Múltiples/cirugía , Tejido Adiposo , Mamoplastia , Tejido Adiposo/trasplante , Estética , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
12.
Molecules ; 26(9)2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-34068579

RESUMEN

The Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused the "COVID-19" disease that has been declared by WHO as a global emergency. The pandemic, which emerged in China and widespread all over the world, has no specific treatment till now. The reported antiviral activities of isoflavonoids encouraged us to find out its in silico anti-SARS-CoV-2 activity. In this work, molecular docking studies were carried out to investigate the interaction of fifty-nine isoflavonoids against hACE2 and viral Mpro. Several other in silico studies including physicochemical properties, ADMET and toxicity have been preceded. The results revealed that the examined isoflavonoids bound perfectly the hACE-2 with free binding energies ranging from -24.02 to -39.33 kcal mol-1, compared to the co-crystallized ligand (-21.39 kcal mol-1). Furthermore, such compounds bound the Mpro with unique binding modes showing free binding energies ranging from -32.19 to -50.79 kcal mol-1, comparing to the co-crystallized ligand (binding energy = -62.84 kcal mol-1). Compounds 33 and 56 showed the most acceptable affinities against hACE2. Compounds 30 and 53 showed the best docking results against Mpro. In silico ADMET studies suggest that most compounds possess drug-likeness properties.


Asunto(s)
Enzima Convertidora de Angiotensina 2/química , Tratamiento Farmacológico de COVID-19 , Proteasas 3C de Coronavirus/química , Sistemas de Liberación de Medicamentos , Isoflavonas/química , Simulación del Acoplamiento Molecular , Enzima Convertidora de Angiotensina 2/metabolismo , Proteasas 3C de Coronavirus/metabolismo , Humanos , Isoflavonas/uso terapéutico
13.
Aesthet Surg J ; 41(6): NP388-NP401, 2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-33300983

RESUMEN

BACKGROUND: Auto-augmentation mastopexy after implant removal has been described as a possible alternative for women who do not opt for implant replacement and decline major reconstructive surgery. OBJECTIVES: This study aimed to evaluate patient satisfaction after auto-augmentation mastopexy relative to the final breast volume and to assess the role of fat grafting on patients' satisfaction and quality of life according to the BREAST-Q questionnaire. METHODS: Forty-seven breasts from 28 patients who underwent implant removal and auto-augmentation mastopexy were reviewed; 9 patients (group 1) were primarily treated with several fat grafting sessions with subsequent auto-augmentation, 5 (group 2) were treated primarily with auto-augmentation, but subsequently expressed a wish for breast augmentation by lipofilling, and 14 patients (group 3, control) had only auto-augmentation. RESULTS: Group 1 patients maintained their breast volume, and showed significant improvements in breast satisfaction, psychosocial well-being, and contentment with breast surgery outcomes (P = 0.01, ˂0.01, and ˂0.01, respectively). However, the physical well-being of this group, as well as response to final cup size or interaction parameters, did not improve (P = 0.06). In group 2, all except 1 patient had breast volume reduction to A cup, as was the case with one-third of the patients in control group 3 (group 3A, n = 5) who scored lower, and thus were less satisfied with the breast auto-augmentation than group 3B, who achieved final bigger cup sizes (P ˂ 0.01). CONCLUSIONS: Auto-augmentation mastopexy resulted in substantial improvements in the parameters measured by BREAST-Q. Thus, combined auto-augmentation mastopexy and lipofilling provided a better alternative treatment after breast implant removal.


Asunto(s)
Implantación de Mama , Implantes de Mama , Mamoplastia , Tejido Adiposo , Implantación de Mama/efectos adversos , Femenino , Humanos , Mamoplastia/efectos adversos , Satisfacción del Paciente , Calidad de Vida , Estudios Retrospectivos
14.
Mol Microbiol ; 112(1): 81-98, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30983025

RESUMEN

Disarming pathogens by targeting virulence factors is a promising alternative to classic antibiotics. Many virulence factors in Gram-negative bacteria are secreted via the autotransporter (AT) pathway, also known as Type 5 secretion. These factors are secreted with the assistance of two membrane-based protein complexes: Sec and Bam. To identify inhibitors of the AT pathway, we used transcriptomics analysis to develop a fluorescence-based high-throughput assay that reports on the stress induced by the model AT hemoglobin protease (Hbp) when its secretion across the outer membrane is inhibited. Screening a library of 1600 fragments yielded the compound VUF15259 that provokes cell envelope stress and secretion inhibition of the ATs Hbp and Antigen-43. VUF15259 also impairs ß-barrel folding activity of various outer membrane proteins. Furthermore, we found that mutants that are compromised in outer membrane protein biogenesis are more susceptible to VUF15259. Finally, VUF15259 induces the release of vesicles that appear to assemble in short chains. Taken together, VUF15259 is the first reported compound that inhibits AT secretion and our data are mostly consistent with VUF15259 interfering with the Bam-complex as potential mode of action. The validation of the presented assay incites its use to screen larger compound libraries with drug-like compounds.


Asunto(s)
Sistemas de Secreción Tipo V/antagonistas & inhibidores , Sistemas de Secreción Tipo V/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo , Transporte Biológico , Membrana Celular/metabolismo , Endopeptidasas/metabolismo , Bacterias Gramnegativas , Proteínas de Transporte de Membrana/metabolismo , Modelos Moleculares , Pliegue de Proteína , Estructura Terciaria de Proteína , Transporte de Proteínas/fisiología , Canales de Translocación SEC/antagonistas & inhibidores , Canales de Translocación SEC/metabolismo , Factores de Virulencia/metabolismo
15.
BMC Med ; 18(1): 24, 2020 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-32014024

RESUMEN

BACKGROUND: Atypical Beijing genotype Mycobacterium tuberculosis strains are widespread in South Africa and have acquired resistance to up to 13 drugs on multiple occasions. It is puzzling that these strains have retained fitness and transmissibility despite the potential fitness cost associated with drug resistance mutations. METHODS: We conducted Illumina sequencing of 211 Beijing genotype M. tuberculosis isolates to facilitate the detection of genomic features that may promote acquisition of drug resistance and restore fitness in highly resistant atypical Beijing forms. Phylogenetic and comparative genomic analysis was done to determine changes that are unique to the resistant strains that also transmit well. Minimum inhibitory concentration (MIC) determination for streptomycin and bedaquiline was done for a limited number of isolates to demonstrate a difference in MIC between isolates with and without certain variants. RESULTS: Phylogenetic analysis confirmed that two clades of atypical Beijing strains have independently developed resistance to virtually all the potent drugs included in standard (pre-bedaquiline) drug-resistant TB treatment regimens. We show that undetected drug resistance in a progenitor strain was likely instrumental in this resistance acquisition. In this cohort, ethionamide (ethA A381P) resistance would be missed in first-line drug-susceptible isolates, and streptomycin (gidB L79S) resistance may be missed due to an MIC close to the critical concentration. Subsequent inadequate treatment historically led to amplification of resistance and facilitated spread of the strains. Bedaquiline resistance was found in a small number of isolates, despite lack of exposure to the drug. The highly resistant clades also carry inhA promoter mutations, which arose after ethA and katG mutations. In these isolates, inhA promoter mutations do not alter drug resistance, suggesting a possible alternative role. CONCLUSION: The presence of the ethA mutation in otherwise susceptible isolates from ethionamide-naïve patients demonstrates that known exposure is not an adequate indicator of drug susceptibility. Similarly, it is demonstrated that bedaquiline resistance can occur without exposure to the drug. Inappropriate treatment regimens, due to missed resistance, leads to amplification of resistance, and transmission. We put these results into the context of current WHO treatment regimens, underscoring the risks of treatment without knowledge of the full drug resistance profile.


Asunto(s)
Genómica/métodos , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Epidemias , Femenino , Humanos , Masculino , Mutación
16.
Artículo en Inglés | MEDLINE | ID: mdl-29661879

RESUMEN

Due to the rise of drug-resistant forms of tuberculosis, there is an urgent need for novel antibiotics to effectively combat these cases and shorten treatment regimens. Recently, drug screens using whole-cell analyses have been shown to be successful. However, current high-throughput screens focus mostly on stricto sensu life/death screening that give little qualitative information. In doing so, promising compound scaffolds or nonoptimized compounds that fail to reach inhibitory concentrations are missed. To accelerate early tuberculosis (TB) drug discovery, we performed RNA sequencing on Mycobacterium tuberculosis and Mycobacterium marinum to map the stress responses that follow upon exposure to subinhibitory concentrations of antibiotics with known targets, ciprofloxacin, ethambutol, isoniazid, streptomycin, and rifampin. The resulting data set comprises the first overview of transcriptional stress responses of mycobacteria to different antibiotics. We show that antibiotics can be distinguished based on their specific transcriptional stress fingerprint. Notably, this fingerprint was more distinctive in M. marinum We decided to use this to our advantage and continue with this model organism. A selection of diverse antibiotic stress genes was used to construct stress reporters. In total, three functional reporters were constructed to respond to DNA damage, cell wall damage, and ribosomal inhibition. Subsequently, these reporter strains were used to screen a small anti-TB compound library to predict the mode of action. In doing so, we identified the putative modes of action for three novel compounds, which confirms the utility of our approach.


Asunto(s)
Antituberculosos/farmacología , Descubrimiento de Drogas/métodos , Mycobacterium marinum/efectos de los fármacos , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis Pulmonar/tratamiento farmacológico , Animales , Secuencia de Bases , Línea Celular , Ciprofloxacina/farmacología , Etambutol/farmacología , Humanos , Isoniazida/farmacología , Macrófagos/efectos de los fármacos , Ratones , Mycobacterium marinum/genética , Mycobacterium tuberculosis/genética , Células RAW 264.7 , ARN Bacteriano/genética , Rifampin/farmacología , Análisis de Secuencia de ARN , Estreptomicina/farmacología , Transcripción Genética/efectos de los fármacos , Transcripción Genética/genética , Tuberculosis Pulmonar/microbiología
17.
PLoS Genet ; 11(5): e1005190, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25938982

RESUMEN

Mycobacteria possess different type VII secretion (T7S) systems to secrete proteins across their unusual cell envelope. One of these systems, ESX-5, is only present in slow-growing mycobacteria and responsible for the secretion of multiple substrates. However, the role of ESX-5 substrates in growth and/or virulence is largely unknown. In this study, we show that esx-5 is essential for growth of both Mycobacterium marinum and Mycobacterium bovis. Remarkably, this essentiality can be rescued by increasing the permeability of the outer membrane, either by altering its lipid composition or by the introduction of the heterologous porin MspA. Mutagenesis of the first nucleotide-binding domain of the membrane ATPase EccC5 prevented both ESX-5-dependent secretion and bacterial growth, but did not affect ESX-5 complex assembly. This suggests that the rescuing effect is not due to pores formed by the ESX-5 membrane complex, but caused by ESX-5 activity. Subsequent proteomic analysis to identify crucial ESX-5 substrates confirmed that all detectable PE and PPE proteins in the cell surface and cell envelope fractions were routed through ESX-5. Additionally, saturated transposon-directed insertion-site sequencing (TraDIS) was applied to both wild-type M. marinum cells and cells expressing mspA to identify genes that are not essential anymore in the presence of MspA. This analysis confirmed the importance of esx-5, but we could not identify essential ESX-5 substrates, indicating that multiple of these substrates are together responsible for the essentiality. Finally, examination of phenotypes on defined carbon sources revealed that an esx-5 mutant is strongly impaired in the uptake and utilization of hydrophobic carbon sources. Based on these data, we propose a model in which the ESX-5 system is responsible for the transport of cell envelope proteins that are required for nutrient uptake. These proteins might in this way compensate for the lack of MspA-like porins in slow-growing mycobacteria.


Asunto(s)
Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Mycobacterium bovis/genética , Mycobacterium marinum/genética , Sistemas de Secreción Tipo VII/metabolismo , Ampicilina/farmacología , Proteínas Bacterianas/genética , Permeabilidad de la Membrana Celular , Cromatografía Liquida , Elementos Transponibles de ADN , ADN Bacteriano/genética , Farmacorresistencia Bacteriana , Mutación , Mycobacterium bovis/metabolismo , Mycobacterium marinum/metabolismo , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Análisis de Secuencia de ADN , Espectrometría de Masas en Tándem , Sistemas de Secreción Tipo VII/genética
18.
Bioorg Med Chem ; 25(4): 1496-1513, 2017 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-28117121

RESUMEN

In our effort to develop potent anti-hyperglycemic agents with potential agonistic activities toward PPARγ and SUR, three novel series of quinoxaline derivatives bearing sulfonylurea or sulfonylthiourea moieties with different linkers were designed and synthesized. Some of the newly synthesized compounds were evaluated in vivo for their anti-hyperglycemic activities in STZ-induced hyperglycemic rats. Compounds 15a, 15e, 19b and 24a exhibited the highest anti-hyperglycemic activities with % reduction in blood glucose level of (50.58, 43.84, 45.10 and 49.62, respectively). Additionally, eight compounds revealed potent anti-hyperglycemic activities were further evaluated in vitro for their PPARγ binding affinity and insulin-secreting ability as potential mechanisms for anti-hyperglycemic activity. Four compounds (15a, 15b, 15d and 15e) significantly bound to PPARγ with IC50 values of 0.482, 0.491, 0.350 and 0.369µM, respectively. Moreover, Compounds 15a and 15b have demonstrated induction of insulin-secretion with EC50 values of 0.92 and 0.98µM, respectively. Furthermore, molecular docking and pharmacophore generation techniques were carried out to investigate binding patterns and fit values of the designed compounds with PPARγ and SUR, respectively.


Asunto(s)
Antihipertensivos/farmacología , Diseño de Fármacos , Hiperglucemia/tratamiento farmacológico , PPAR gamma/agonistas , Quinoxalinas/farmacología , Receptores de Sulfonilureas/agonistas , Animales , Antihipertensivos/síntesis química , Antihipertensivos/química , Relación Dosis-Respuesta a Droga , Hiperglucemia/inducido químicamente , Masculino , Modelos Moleculares , Estructura Molecular , Quinoxalinas/síntesis química , Quinoxalinas/química , Ratas , Ratas Wistar , Estreptozocina , Relación Estructura-Actividad
19.
Adv Exp Med Biol ; 1019: 155-169, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29116634

RESUMEN

BCG vaccines were derived by in vitro passage, during the years 1908-1921, at the Pasteur Institute of Lille. Following the distribution of stocks of BCG to vaccine production laboratories around the world, it was only a few decades before different BCG producers recognized that there were variants of BCG, likely due to different passaging conditions in the different laboratories. This ultimately led to the lyophilization of stable BCG products in the 1950s and 1960s, but not before considerable evolution of the different BCG strains had taken place. The application of contemporary research methodologies has now revealed genomic, transcriptomic and proteomic differences between BCG strains. These molecular differences in part account for phenotypic differences in vitro between BCG strains, such as their variable secretion of antigenic proteins. Yet, the relevance of BCG variability for immunization policy remains elusive. In this chapter we present an overview of what is known about BCG evolution and its resulting strain variability, and provide some speculation as to the potential relevance for a vaccine given to over 100 million newborns each year.


Asunto(s)
Variación Antigénica , Vacuna BCG/inmunología , Vacunación Masiva , Mycobacterium bovis/genética , Mycobacterium tuberculosis/genética , Tuberculosis Pulmonar/prevención & control , Animales , Vacuna BCG/administración & dosificación , Vacuna BCG/química , Vacuna BCG/historia , Bovinos , Evolución Molecular , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Recién Nacido , Mycobacterium bovis/química , Mycobacterium bovis/clasificación , Mycobacterium bovis/inmunología , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/inmunología , Fenotipo , Filogenia , Proteómica , Tuberculosis Pulmonar/inmunología , Tuberculosis Pulmonar/microbiología
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