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1.
EMBO Rep ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38969946

RESUMEN

Plasma membrane repair is a fundamental homeostatic process of eukaryotic cells. Here, we report a new function for the conserved cytoskeletal proteins known as septins in the repair of cells perforated by pore-forming toxins or mechanical disruption. Using a silencing RNA screen, we identified known repair factors (e.g. annexin A2, ANXA2) and novel factors such as septin 7 (SEPT7) that is essential for septin assembly. Upon plasma membrane injury, the septin cytoskeleton is extensively redistributed to form submembranous domains arranged as knob and loop structures containing F-actin, myosin IIA, S100A11, and ANXA2. Formation of these domains is Ca2+-dependent and correlates with plasma membrane repair efficiency. Super-resolution microscopy revealed that septins and F-actin form intertwined filaments associated with ANXA2. Depletion of SEPT7 prevented ANXA2 recruitment and formation of submembranous actomyosin domains. However, ANXA2 depletion had no effect on domain formation. Collectively, our data support a novel septin-based mechanism for resealing damaged cells, in which the septin cytoskeleton plays a key structural role in remodeling the plasma membrane by promoting the formation of SEPT/F-actin/myosin IIA/ANXA2/S100A11 repair domains.

2.
Environ Res ; 214(Pt 3): 113995, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35932830

RESUMEN

Air pollution is becoming a distinctly growing concern and the most pressing universal problem as a result of increased energy consumption, with the multiplication of the human population and industrial enterprises, resulting in the generation of hazardous pollutants. Among these, carbon monoxide, nitrogen oxides, Volatile organic compounds, Semi volatile organic compounds, and other inorganic gases not only have an adverse impact on human health both outdoors and indoors, but have also substantially altered the global climate, resulting in several calamities around the world. Thus, the purification of air is a crucial matter to deal with. Photocatalytic oxidation is one of the most recent and promising technologies, and it has been the subject of numerous studies over the past two decades. Hence, the photocatalyst is the most reassuring aspirant due to its adequate bandgap and exquisite stability. The process of photocatalysis has provided many benefits to the atmosphere by removing pollutants. In this review, our work focuses on four main themes. Firstly, we briefly elaborated on the general mechanism of air pollutant degradation, followed by an overview of the typical TiO2 photocatalyst, which is the most researched photocatalyst for photocatalytic destruction of gaseous VOCs. The influence of operating parameters influencing the process of photocatalytic oxidation (such as mass transfer, light source and intensity, pollutant concentration, and relative humidity) was then summarized. Afterwards, the progress and drawbacks of some typical photoreactors (including monolithic reactors, microreactors, optical fiber reactors, and packed bed reactors) were described and differentiated. Lastly, the most noteworthy coverage is dedicated to different types of modification strategies aimed at ameliorating the performance of photocatalysts for degradation of air pollutants, which were proposed and addressed. In addition, the review winds up with a brief deliberation for more exploration into air purification photocatalysis.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Ambientales , Compuestos Orgánicos Volátiles , Contaminación del Aire/prevención & control , Catálisis , Gases , Humanos , Metales , Titanio
3.
J Contemp Dent Pract ; 23(6): 606-612, 2022 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-36259299

RESUMEN

AIM: To compare the expansion of maxillary antrum between periapical surgery and extraction of permanent maxillary first molar in pediatric patients using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: In this study, 136 participants in the age-group of 11-18 years were included. The participants were divided into two groups. Group A consisted of patients who underwent extraction of the permanent maxillary first molars. Group B consisted of patients who underwent endodontic microsurgery in the periapical area. Group A included 68 participants while group B also included 68 study subjects. The expansion of the maxillary antrum was obtained after evaluating the change in volume of maxillary antrum at 6 months and 24 months in relation to the volume of maxillary antrum at the time of the procedure (baseline). For calculating the volume of the maxillary antrum, three parameters were taken into consideration. These parameters were an anteroposterior (AP) dimension, mesiodistal dimension (MD), and superoinferior (SI) dimension. Cone-beam computed tomography was used for carrying out these measurements with the help of Dolphin software. RESULTS: An expansion of 675.27 ± 32 mm3 was observed in group A between baseline and 6 months of extraction, while the expansion of 765.47 ± 24 mm3 was observed between 6 months and 24 months of extraction. This intragroup difference was statistically significant (p = 0.001). On the other hand, an expansion of 652.28 ± 43 mm3 was observed in group B between baseline and 6 months after periapical surgery and expansion of 969.43 ± 12 mm3 was observed between 6 months and 24 months after periapical endodontic surgery. This intragroup difference was statistically significant. In the control group, an expansion of 152.11 ± 12.101 mm3 was observed between baseline and 6 months after procedures while an expansion of 347.01 ± 6.781 mm3 was observed between 6 months and 24 months of procedures. The intragroup difference was significant statistically. CONCLUSION: In this study, expansion of maxillary antrum was observed in both extraction of the maxillary permanent first molar in pediatric patients and the periapical endodontic surgery, and the expansion of maxillary antrum was more in cases of periapical endodontic surgery; however, the difference was non-significant statistically. CLINICAL SIGNIFICANCE: Maxillary antrum expansion is clinically important during maxillary permanent tooth extraction or endodontic periapical surgery in pediatric patients because the growth of maxillary bones is in the growing stage in these patients. There are certain limitations of conventional two-dimensional (2D) radiographic techniques such as shortening, elongation, and superimposition of images. Recently, three-dimensional technique (3D) such as CBCT has been introduced in which these disadvantages have been eliminated.


Asunto(s)
Maxilar , Tomografía Computarizada de Haz Cónico Espiral , Tomografía Computarizada de Haz Cónico/métodos , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Seno Maxilar , Diente Molar/diagnóstico por imagen , Diente Molar/cirugía , Extracción Dental
4.
J Contemp Dent Pract ; 22(9): 1019-1024, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35000946

RESUMEN

AIM AND OBJECTIVE: To compare the different shades of monolithic zirconia over microhardness and water solubility and water sorption of dual-cure resin cement. MATERIALS AND METHODS: Eighty specimens were included in the study. They were categorized into four categories having 20 samples each. Category one: No ceramic disks were present in the control group; the cement was directly activated. Category two: Curing of the resin cement with one shade of monolithic zirconia topping. Category three: Curing of the resin cement with an overlaying layer A monolithic zirconia version with two shades. Category four: Curing of the resin cement with an overlaying layer A three-tone monolithic zirconia version. In each category, two subgroups were further created (n = 10). One subgroup consisted of conventional dual-cure resin-based cement, while the other subgroup consisted of self-adhesive dual-cure resin-based cement. Vickers microhardness, water solubility, and water sorption of resin cement sorption were precisely measured after 24 hours of storage in an incubator at 37°C. The statistical analysis was undertaken with the help of statistical tests like two-way analysis of variations (ANOVA), one-way ANOVA, independent t-tests, Tukey's test, and Tamhane's T2 test. The p ≤0.05 was considered statistically significant. RESULTS: Microhardness was more excellent in conventional dual-cure resin-based cement in comparison with self-adhesive dual-cure cement. At the same time, the water solubility and water sorption were lower in conventional dual-cure resin-based cement than self-adhesive dual-cure resin cement. The effect of shade of monolithic variant of zirconia was significant over the microhardness of both dual-cure resin-based cement; however, the impact was nonsignificant over the water solubility and water sorption of the resin-based resin cement. Further, it was also observed that the use of a monolithic variant of zirconia led to a decrease in microhardness of both dual resin-based cement in comparison to the condition when no ceramics were used. CONCLUSION: The effect of shade of monolithic variant of zirconia was statistically significant over the microhardness of both dual-cure resin-based cement; however, the result was not significant over the water solubility and water sorption of the resin-based cement. The use of a monolithic variant of zirconia led to a decrease in the microhardness of both dual resin-based cement compared to the condition when no ceramics were used. CLINICAL SIGNIFICANCE: The quantity of polymerization in resin-based cement affects their clinical effectiveness for a more extended period. It is believed that the measurement of microhardness is a reliable and straightforward process for evaluating the amount of polymerization of resin-based cement. Very few studies have been conducted in the past to compare the shades of monolithic zirconia over the microhardness, water solubility, and water sorption of the dual-cure resin-based cement.


Asunto(s)
Porcelana Dental , Cementos de Resina , Cerámica , Ensayo de Materiales , Solubilidad , Propiedades de Superficie , Agua , Circonio
5.
Infect Immun ; 86(10)2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30061379

RESUMEN

Listeria monocytogenes is a facultative intracellular pathogen that infects a wide variety of cells, causing the life-threatening disease listeriosis. L. monocytogenes virulence factors include two surface invasins, InlA and InlB, known to promote bacterial uptake by host cells, and the secreted pore-forming toxin listeriolysin O (LLO), which disrupts the phagosome to allow bacterial proliferation in the cytosol. In addition, plasma membrane perforation by LLO has been shown to facilitate L. monocytogenes internalization into epithelial cells. In this work, we tested the host cell range and importance of LLO-mediated L. monocytogenes internalization relative to the canonical invasins, InlA and InlB. We measured the efficiencies of L. monocytogenes association with and internalization into several human cell types (hepatocytes, cytotrophoblasts, and endothelial cells) using wild-type bacteria and isogenic single, double, and triple deletion mutants for the genes encoding InlA, InlB and LLO. No role for InlB was detected in any tested cells unless the InlB expression level was substantially enhanced, which was achieved by introducing a mutation (prfA*) in the gene encoding the transcription factor PrfA. In contrast, InlA and LLO were the most critical invasion factors, although they act in a different manner and in a cell-type-dependent fashion. As expected, InlA facilitates both bacterial attachment and internalization in cells that express its receptor, E-cadherin. LLO promotes L. monocytogenes internalization into hepatocytes, but not into cytotrophoblasts and endothelial cells. Finally, LLO and InlA cooperate to increase the efficiency of host cell invasion by L. monocytogenes.


Asunto(s)
Proteínas Bacterianas/metabolismo , Toxinas Bacterianas/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas Hemolisinas/metabolismo , Listeria monocytogenes/metabolismo , Listeriosis/microbiología , Proteínas de la Membrana/metabolismo , Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Cadherinas/genética , Cadherinas/metabolismo , Proteínas de Choque Térmico/genética , Proteínas Hemolisinas/genética , Hepatocitos/metabolismo , Hepatocitos/microbiología , Humanos , Listeria monocytogenes/genética , Listeria monocytogenes/patogenicidad , Listeriosis/genética , Listeriosis/metabolismo , Proteínas de la Membrana/genética , Factores de Terminación de Péptidos/genética , Factores de Terminación de Péptidos/metabolismo , Virulencia
6.
Int J Cancer ; 136(12): 2775-85, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25388642

RESUMEN

Head and neck squamous cell carcinoma (HNSCC) is frequently characterized by high resistance to radiotherapy, which critically depends on both altered signaling pathways within tumor cells and their dynamic interaction with the tumor microenvironment. This study evaluated the prognostic value of the phosphorylation status of AKT on Ser473 and Thr308 for the clinical outcome of patients with advanced HNSCC on radiotherapy. Furthermore, we investigated the impact of AKT(Ser473) phosphorylation [p-AKT(Ser473)] in the context of radioresistance using ex vivo tissue cultures that resemble the complex tissue architecture and paracrine interaction with the tumor microenvironment. In a cohort of 120 patients with advanced HNSCC, who were treated with primary or adjuvant radiotherapy, a significant association was found between relative p-AKT(Ser473) levels and overall survival (p = 0.006) as well as progression-free survival (p = 0.021), while no significant correlation was revealed for relative p-AKT(Thr308) levels. In ex vivo tissue cultures p-AKT(Ser473) levels were increased upon irradiation and treatment with the PI3K inhibitor LY294002 inhibited both basal and irradiation induced AKT(Ser473) phosphorylation. Strikingly, pretreatment with LY294002 sensitized tissue cultures derived from primary and recurrent tumors to radiotherapy as determined by impaired tumor cell proliferation and enhanced DNA damage. In conclusion, phosphorylation status of AKT(Ser473) in tumor specimens serves as a novel biomarker to identify patients with advanced HNSCC at high risk for treatment failure following radiotherapy, and our data from ex vivo tissue cultures support the assumption that pharmacological inhibition of AKT(Ser473) phosphorylation might circumvent radioresistance to improve efficiency and reduce toxicity of current treatment modalities.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeza y Cuello/radioterapia , Proteínas Proto-Oncogénicas c-akt/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Cromonas/farmacología , Inhibidores Enzimáticos/farmacología , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Morfolinas/farmacología , Análisis Multivariante , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosforilación/efectos de los fármacos , Fosforilación/efectos de la radiación , Tolerancia a Radiación/efectos de los fármacos , Tolerancia a Radiación/efectos de la radiación , Serina/metabolismo , Análisis de Supervivencia , Treonina/metabolismo , Técnicas de Cultivo de Tejidos
7.
Helicobacter ; 19(2): 116-23, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24237714

RESUMEN

BACKGROUND AND AIMS: (14) C-urea breath test ((14) C-UBT) is considered as "gold standard" for detection of active gastric H. pylori infection. However, till date no comparative study using encapsulated and non-encapsulated (14) C-UBT protocols has been conducted in same subjects in identical conditions. We monitored gastric fate of capsule containing (14) C-urea with real time display and compared sensitivities of these protocols at different time points of breath collection. METHODS: Non-encapsulated (14) C-UBT was performed using 74 kBq of (14) C-urea in 100 dyspeptic patients by collecting breath samples at 10, 15 and 20 minutes. Thereafter, within 2 days a gelatin capsule containing (14) C-urea along with 6.0 MBq of (99m) Tc-diethylene triamine penta-acetic acid was administered to each patient for real time display of capsule movement and its fate in gastrointestinal tract by gamma camera. Simultaneously, breath samples were collected for (14) CO2 measurement during image acquisition. RESULTS: Employing non-encapsulated (14) C-UBT, 74 out of 100 dyspeptic patients were found to be H. pylori positive. Discordant (14) C-UBT results were obtained in 4/74 (5.4%) cases using these two protocols. By employing encapsulated and nonencapsulated (14) C-UBT protocols, sensitivities of (14) C-UBT were found to be 90.5 versus 98.6% at 10 and 91.8 versus 97.2% at 15 minutes respectively; while these were 94.6 versus 100, 90.7 versus 98.6 and 83.7 versus 93.2% considering any one, two or all three positive values respectively. CONCLUSIONS: Incomplete/non-resolution of (14) C-urea capsule in stomach during the phase of breath collections appears to decrease sensitivity of encapsulated (14) C-UBT as compared to nonencapsulated protocol for detection of H. pylori infection.


Asunto(s)
Infecciones por Helicobacter/diagnóstico por imagen , Infecciones por Helicobacter/diagnóstico , Estómago/microbiología , Urea/análisis , Adulto , Anciano , Pruebas Respiratorias/métodos , Radioisótopos de Carbono , Femenino , Gastritis/diagnóstico , Gastritis/diagnóstico por imagen , Gastritis/microbiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori , Humanos , Masculino , Persona de Mediana Edad , Úlcera Péptica/microbiología , Poliaminas , Cintigrafía , Sensibilidad y Especificidad , Estómago/patología , Úlcera Gástrica/microbiología , Adulto Joven
8.
Int J Biol Macromol ; 257(Pt 1): 128563, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38070800

RESUMEN

Biofilm formation by Pseudomonas aeruginosa is primarily responsible for chronic wound and lung infections in humans. These infections are persistent owing to the biofilm's high tolerance to antimicrobials and constantly changing environmental factors. Understanding the mechanism governing biofilm formation can help to develop therapeutics explicitly directed against the molecular markers responsible for this process. After numerous years of research, many genes responsible for both in vitro and in vivo biofilm development remain unidentified. However, there is no "all in one" complete in vivo or in vitro biofilm model. Recent findings imply that the shift from planktonic bacteria to biofilms is a complicated and interrelated differentiation process. Research on the applications of omics technologies in P. aeruginosa biofilm development is ongoing, and these approaches hold great promise for expanding our knowledge of the mechanisms of biofilm formation. This review discusses the different factors that affect biofilm formation and compares P. aeruginosa biofilm formation using the omics approaches targeting essential biological macromolecules, such as DNA, RNA, Protein, and metabolome. Furthermore, we have outlined the application of currently available omics tools, such as genomics, proteomics, metabolomics, transcriptomics, and integrated multi-omics methodologies, to understand the differential gene expression (biofilm vs. planktonic bacteria) of P. aeruginosa biofilms.


Asunto(s)
Infecciones por Pseudomonas , Pseudomonas aeruginosa , Humanos , Proteómica , Plancton/genética , Multiómica , Biopelículas , Infecciones por Pseudomonas/microbiología , Bacterias/genética , Perfilación de la Expresión Génica
9.
J Infect Dev Ctries ; 18(4): 579-586, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38728636

RESUMEN

INTRODUCTION: Streptococcus pneumoniae cause a significant global health challenge. We aimed to determine nasopharyngeal carriage, serotypes distribution, and antimicrobial profile of pneumococci among the children of Aden. METHODOLOGY: A total of 385 children, aged 2-17 years, were included. Asymptomatic samples were randomly collected from children in selected schools and vaccination centers. Symptomatic samples were obtained from selected pediatric clinics. The nasopharyngeal swabs were tested for pneumococci using culture and real time polymerase chain reaction (RT-PCR). Serotyping was done with a pneumotest-latex kit and antimicrobial susceptibility was tested by disc diffusion and Epsilometer test. RESULTS: The total pneumococcal carriage was 44.4% and 57.1% by culture and RT-PCR, respectively. There was a statistically significant association between carriage rate and living in single room (OR = 7.9; p = 0.00001), sharing a sleeping space (OR = 15.1; p = 0.00001), and low monthly income (OR = 2.02; p = 0.007). The common serotypes were 19, 1, 4, 5, 2, and 23. The proportion of non-pneumococcal conjugate vaccine (non-PCV13) serotypes was 24%. Pneumococci were resistant to penicillin (96.5%), cefepime (15.8%), ceftriaxone (16.4%), and amoxicillin-clavulanate (0%). Erythromycin, azithromycin, and doxycycline had resistance rates of 48%, 31%, and 53.3%, respectively. CONCLUSIONS: A high pneumococcal carriage rate was observed in Yemeni children, particularly in low-income households and shared living conditions. There was significant penicillin resistance at meningitis breakpoint. Furthermore, non-PCV13 serotypes were gradually replacing PCV13 serotypes. The findings underscore the urgent need for enhanced surveillance and stewardship to improve vaccination and antibiotic policies in Yemen.


Asunto(s)
Portador Sano , Nasofaringe , Infecciones Neumocócicas , Vacunas Neumococicas , Serogrupo , Streptococcus pneumoniae , Vacunas Conjugadas , Humanos , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/aislamiento & purificación , Streptococcus pneumoniae/clasificación , Niño , Preescolar , Estudios Transversales , Yemen/epidemiología , Infecciones Neumocócicas/epidemiología , Infecciones Neumocócicas/prevención & control , Infecciones Neumocócicas/microbiología , Femenino , Masculino , Vacunas Neumococicas/administración & dosificación , Adolescente , Portador Sano/epidemiología , Portador Sano/microbiología , Nasofaringe/microbiología , Vacunas Conjugadas/administración & dosificación , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Serotipificación
10.
bioRxiv ; 2024 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-37503091

RESUMEN

Mammalian cells are frequently exposed to mechanical and biochemical stressors resulting in plasma membrane injuries. Repair mechanisms reseal the plasma membrane to restore homeostasis and prevent cell death. In the present work, a silencing RNA screen was performed to uncover plasma membrane repair mechanisms of cells exposed to a pore-forming toxin (listeriolysin O). This screen identified molecules previously known to repair the injured plasma membrane such as annexin A2 (ANXA2) as well as novel plasma membrane repair candidate proteins. Of the novel candidates, we focused on septin 7 (SEPT7) because the septins are an important family of conserved eukaryotic cytoskeletal proteins. Using diverse experimental approaches, we established for the first time that SEPT7 plays a general role in plasma membrane repair of cells perforated by pore-forming toxins and mechanical wounding. Remarkably, upon cell injury, the septin cytoskeleton is extensively redistributed in a Ca 2+ -dependent fashion, a hallmark of plasma membrane repair machineries. The septins reorganize into subplasmalemmal domains arranged as knob and loop (or ring) structures containing F-actin, myosin II, and annexin A2 (ANXA2) and protrude from the cell surface. Importantly, the formation of these domains correlates with the plasma membrane repair efficiency. Super-resolution microscopy shows that septins and actin are arranged in intertwined filaments associated with ANXA2. Silencing SEPT7 expression prevented the formation of the F-actin/myosin II/ANXA2 domains, however, silencing expression of ANXA2 had no observable effect on their formation. These results highlight the key structural role of the septins in remodeling the plasma membrane and in the recruitment of the repair molecule ANXA2. Collectively, our data support a novel model in which the septin cytoskeleton acts as a scaffold to promote the formation of plasma membrane repair domains containing contractile F-actin and annexin A2.

11.
Biomedicines ; 11(7)2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37509635

RESUMEN

The human commensal yeast Candida albicans is pathogenic and results in a variety of mucosal and deep tissue problems when the host is immunocompromised. Candida exhibits enormous metabolic flexibility and dynamic morphogenetic transition to survive under host niche environmental conditions and to cause virulence. The amino sugar N-acetylglucosamine (GlcNAc) available at the host infection sites, apart from acting as an extremely good carbon and nitrogen source, also induces cellular signalling in this pathogen. In C. albicans, GlcNAc performs multifaceted roles, including GlcNAc scavenging, GlcNAc import and metabolism, morphogenetic transition (yeast-hyphae and white-opaque switch), GlcNAc-induced cell death (GICD), and virulence. Understanding the molecular mechanism(s) involved in GlcNAc-induced cellular processes has become the main focus of many studies. In the current study, we focused on GlcNAc-induced metabolic changes associated with phenotypic changes. Here, we employed gas chromatography-mass spectrometry (GC-MS), which is a high-throughput and sensitive technology, to unveil global metabolomic changes that occur in GlcNAc vs. glucose grown conditions in Candida cells. The morphogenetic transition associated with metabolic changes was analysed by high-resolution field emission scanning electron microscopy (FE-SEM). Metabolite analysis revealed the upregulation of metabolites involved in the glyoxylate pathway, oxidative metabolism, and fatty acid catabolism to probably augment the synthesis of GlcNAc-induced hypha-specific materials. Furthermore, GlcNAc-grown cells showed slightly more sensitivity to amphotericin B treatment. These results all together provide new insights into the development of antifungal therapeutics for the control of candidiasis in humans.

12.
IEEE Trans Nanobioscience ; 22(3): 582-589, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36350861

RESUMEN

In this communication, we purpose an alternative electrical method to determine the anti-bacterial activity of compounds. Polyaniline/magnetite (Fe3O4/PANI) and polyaniline/hydrochloric acid (HCl/PANI) nanocomposites have been prepared. We have tested the anti-bacterial activity of Fe3O4/PANI and HCl/PANI nanocomposites by Agarwell Diffusion Assay and Bacterial Inhibition Assay method. The electrical characteristics of the prepared composites have been measured. The doping of 12% of Fe3O4 in PANI caused a substantial increase in anti-bacterial activity. The observed bacterial inhibition is in agreement with optimized values of resistivity, loss factor, quality factor, and spontaneous magnetization. Sample 2 associated with 12% Fe3O4-PANI composites has a high resistivity of 1.70×106Ω .m among all prepared composites. The magnetic character and insulating nature of Fe3O4 influenced the investigated parameters. The morphological variation of prepared composites is also consistent with electrical parameters. The alleviated energy zone formed by the magnetic behavior of Fe3O4 and interfacial polarization of PANI mitigates the polarization/field of charge carriers of bacteria. These effects altogether diminish the energy of bacterial zone revealed in the experiment. The tuning of electrical parameters provides an alternative to control bacterial growth in various compounds. The proposed method of electrical characterization for the detection of the anti-bacterial activity of the compounds can be very useful in terms of time and cost in contrast to the lab tests performed in biological labs. After implementing an electrical parameter standard equivalent to anti-bacterial activity, real-time detection can be performed by electrical parameters in the fields outside without any hassle, which otherwise is not possible for biological labs.


Asunto(s)
Nanocompuestos , Nanocompuestos/química , Bacterias , Compuestos de Anilina/farmacología , Compuestos de Anilina/química , Conductividad Eléctrica
13.
J Cancer Res Ther ; 19(5): 1415-1418, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37787318

RESUMEN

Common copy number variations often contain cancer-related genes and are likely to play a role in carcinogenesis. Different mechanisms of tumorigenesis are suggested in female and male breast cancer because of different molecular profiles. The cytogenetic analysis of GTG-banded chromosomes was performed in six male patients with infiltrating ductal carcinoma and six healthy male controls matched for age. Single-nucleotide polymorphism (SNP) array analysis was performed in male breast cancer (MBC) patients. Cytogenetic analysis found aberrations previously implicated in cancer. SNP array analysis in patients revealed a gain of Xp11.23, 8p23.2, Yq11.221, Yq11.3 (AZF region), 12p11.21, 18q12.1, and 17q21.3; a loss of Yq11.222 and 7q11.21; and a loss of heterozygosity of 4p16.3, 6p12.3, 6p22.2-p21.31, 7p14.2-14.1, 18q11.2-q12.1, 20p11.23-11.1, 20q11.21-11.23, 1q25.2-q25.3, 2q11.1-q11.2, 5q23.1-23.2, 11p15.4-15.3, and 22q13.1-13.31. Some of these variations, especially those of the Y-chromosome, have not been reported earlier. Chromosomal loci identified by SNP array harbor genes were reported to be associated with cancer progression and metastasis, indicating their involvement in MBC also.


Asunto(s)
Neoplasias de la Mama Masculina , Variaciones en el Número de Copia de ADN , Humanos , Masculino , Femenino , Neoplasias de la Mama Masculina/genética , Aberraciones Cromosómicas , Análisis Citogenético , Oncogenes , Polimorfismo de Nucleótido Simple
14.
Curr Pharm Des ; 29(39): 3137-3153, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38031774

RESUMEN

One-third of people will be diagnosed with cancer at some point in their lives, making it the second leading cause of death globally each year after cardiovascular disease. The complex anticancer molecular mechanisms have been understood clearly with the advent of improved genomic, proteomic, and bioinformatics. Our understanding of the complex interplay between numerous genes and regulatory genetic components within cells explaining how this might lead to malignant phenotypes has greatly expanded. It was discovered that epigenetic resistance and a lack of multitargeting drugs were highlighted as major barriers to cancer treatment, spurring the search for innovative anticancer treatments. It was discovered that epigenetic resistance and a lack of multitargeting drugs were highlighted as major barriers to cancer treatment, spurring the search for innovative anticancer treatments. Many popular anticancer drugs, including irinotecan, vincristine, etoposide, and paclitaxel, have botanical origins. Actinomycin D and mitomycin C come from bacteria, while bleomycin and curacin come from marine creatures. However, there is a lack of research evaluating the potential of algae-based anticancer treatments, especially in terms of their molecular mechanisms. Despite increasing interest in the former, and the promise of the compounds to treat tumours that have been resistant to existing treatment, pharmaceutical development of these compounds has lagged. Thus, the current review focuses on the key algal sources that have been exploited as anticancer therapeutic leads, including their biological origins, phytochemistry, and the challenges involved in converting such leads into effective anticancer drugs.


Asunto(s)
Antineoplásicos , Productos Biológicos , Neoplasias , Humanos , Proteómica , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Desarrollo de Medicamentos , Plantas , Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico
15.
Trop Gastroenterol ; 33(2): 123-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23025059

RESUMEN

BACKGROUND: 14C-urea breath test (14C-UBT) is employed as a 'gold standard' technique for the detection of active gastric Helicobacter pylori infection and is recommended as the best option for "test-and-treat" strategy in primary health care centers. AIM: To compare the performance of capsulated and non-capsulated 14C-UBT protocols for the detection of H. pylori infection in patients. METHODS: Fifty eight H. pylori infected patients underwent routine upper GI endoscopy and biopsies were processed for rapid urease test (RUT) and histopathology examination. Capsulated 14C-UBT was done in a novel way by using 74 kBq of 14C-urea along with 6.0 MBq of 99mTc-diethylene triamine penta-acetic acid (99mTc-DTPA) to simultaneously monitor the movement and the fate of ingested capsule after delineating the stomach contour by using 20.0 MBq of 99mTechnetium pertechnetate (99mTcO4-) under dual head gamma camera. Non-capsulated 14C-UBT was performed within 2 days of the previous test and the results of these protocols were compared. RESULTS: In 3 out of 58 H. pylori positive cases (5.17%), 14C-UBT results were found to be negative by using the capsulated method. Interestingly, on monitoring the real time images of the capsule in these cases it was found that misdiagnosis of H. pylori infection occurred mainly due to either rapid transit of the 14C-urea containing capsule from the upper gastric tract or its incomplete resolution in the stomach during the phase of breath collection. CONCLUSION: Use of non-capsulated '4C-UBT protocol appears to be a superior option than the conventional capsule based technique for the detection of H. pylori infection.


Asunto(s)
Radioisótopos de Carbono , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori , Urea , Pruebas Respiratorias/métodos , Cápsulas , Reacciones Falso Negativas , Infecciones por Helicobacter/microbiología , Humanos , Masculino , Persona de Mediana Edad
16.
Front Plant Sci ; 13: 1076871, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36699860

RESUMEN

Introduction: Barleria prionitis is known for its medicinal properties from ancient times. Bioactive iridoid glycosides and phenolic compounds have been isolated from leaves of this plant. However, other parts of a medicinal plants are also important, especially roots. Therefore, it is important to screen all organs for complete chemical characterization. Method: All parts of B. prionitis, including leaf, root, stem and inflorescence in search of bioactive compounds, with a rapid and effective metabolomic method. X500R QTOF system with information dependent acquisition (IDA) method was used to collect high resolution accurate mass data (HRMS) on both the parent (MS signal) and their fragment ions (MS/MS signal). ESI spectra was obtained in positive ion mode from all parts of the plant. A comparative analysis of antioxidant and antibacterial activity was done and their correlation study with the identified compounds was demonstrated. Principal component analysis was performed. Result: Iridoid glycosides and phenolic compounds were identified from all parts of the showing variability in presence and abundance. Many of the compounds are reported first time in B. prionitis. Antioxidant and antibacterial activity was revealed in all organs, root being the most effective one. Some of the iridoid glycoside and phenolic compounds found to be positively correlated with the tested biological activity. Principal component analysis of the chemical profiles showed variability in distribution of the compounds. Conclusion: All parts of B. prionitis are rich source of bioactive iridoid glycosides and phenolic compounds.

17.
Future Microbiol ; 17: 1501-1513, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36314380

RESUMEN

The microbial communities are an indispensable part of the human defense system and coexist with humans as symbionts, contributing to the metabolic functions and immune defense against pathogens. An ecologically stable vaginal microbiota is dominated by Lactobacillus species, which plays an important role in the prevention of genital infections by controlling the vaginal pH, reducing glycogen to lactic acid, and stimulating bacteriocins and hydrogen peroxide. In contrast, an abnormal vaginal microbial composition is associated with an increased risk of bacterial vaginosis, trichomoniasis, sexually transmitted diseases, preterm labor and other birth defects. This microbial diversity is affected by race, ethnicity, pregnancy, hormonal changes, sexual activities, hygiene practices and other conditions. In the present review, we discuss the changes in the microbial community of the vaginal region at different stages of a female's life cycle and its influence on her reproductive health and pathological conditions.


Asunto(s)
Microbiota , Vaginosis Bacteriana , Humanos , Embarazo , Recién Nacido , Femenino , Salud Reproductiva , Vagina/microbiología , Vaginosis Bacteriana/microbiología , Lactobacillus
18.
Int J Biol Macromol ; 190: 33-43, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34480904

RESUMEN

Staphylococcus aureus is a common cause of skin infections, food poisoning and severe life-threatening infections. Methicillin-Resistant Staphylococcus aureus (MRSA) is known to cause chronic nosocomial infections by virtue of its multidrug resistance and biofilm formation mechanisms. The antimicrobial resistance owned by S. aureus is primarily due to efflux pumps and formation of microbial biofilms. These drug resistant, sessile and densely packed microbial communities possess various mechanisms including quorum sensing and drug efflux. Quorum sensing is a cooperative physiological process which is used by bacterial cells for social interaction and signal transduction in biofilm formation whereas efflux of drugs is derived by efflux pumps. Apart from their significant role in multidrug resistance, efflux pumps also contribute to transporting cell signalling molecules and due to their occurrence; we face the frightening possibility that we will enter the pre-antibiotic era soon. Compounds that modulate efflux pumps are also known as efflux pump inhibitors (EPI's) that act in a synergistic manner and potentiate the antibiotics efficacy which has been considered as a promising approach to encounter bacterial resistance. EPIs inhibit the mechanism of drug efflux s as well as transport of quorum sensing signalling molecules which are the supreme contributors of miscellaneous virulence factors. This review presents an accomplishments of the recent investigations allied to efflux pump inhibitors against S. aureus and also focus on related correspondence between quorum sensing system and efflux pump inhibitors in terms of S. aureus and MRSA biofilms that may open a new avenue for controlling MRSA infections.


Asunto(s)
Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana Múltiple , Percepción de Quorum , Infecciones Estafilocócicas/microbiología , Biopelículas
19.
Br J Radiol ; 94(1122): 20201204, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33979202

RESUMEN

Localizing the sites of infection in the body is possible in nuclear medicine using a variety of radiopharmaceuticals that target different components of the infective and inflammatory cascade. Gamma(γ)-emitting agents such as [67Ga]gallium citrate were among the first tracers used, followed by development of positron-emitting tracers like 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG). Though these tracers are quite sensitive, they have limited specificity for infection due to their concentration in sites of non-infective inflammation. White blood cells (WBC) labelled with γ or positron emitters have higher accuracy for differentiating the infective processes from the non-infective conditions that may show positivity with tracers such as 18F-FDG. We present a pictorial review of potential clinical applications of PET/CT using 18F-FDG labelled WBC.


Asunto(s)
Infecciones/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Fluorodesoxiglucosa F18 , Humanos , Leucocitos , Radiofármacos , Sensibilidad y Especificidad
20.
Nucl Med Commun ; 42(5): 482-489, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33395191

RESUMEN

OBJECTIVE: The present study was performed for head-to-head comparison between 68Ga-prostate-specific membrane antigen (PSMA) PET/computed tomography (CT) and 99mTc-PSMA whole-body and regional single-photon emission computed tomography (SPECT)/CT for the detection of prostate cancer metastases. METHODS: Ten patients with metastatic prostate cancer underwent 99mTc-PSMA whole-body scan after intravenous injection of 230-330 MBq 99mTc-PSMA. Anterior and posterior whole-body images were acquired at 10 min, 2, 4 and/or 5/6 h post-injection. Additional SPECT/CT images were acquired for the involved sites, where planar images did not clearly identify the metastatic sites. All patients also underwent whole-body 68Ga-PSMA PET/CT and the results between the two techniques were compared for the detection of the metastatic lesions. Dosimetry analysis of the 99mTc-PSMA studies was performed using the MIRD-OLINDA approach. RESULTS: 68Ga-PSMA PET/CT detected lesions in all 10 patients, whereas 99mTc-PSMA imaging detected lesions in 9/10 patients. 68Ga-PSMA PET/CT imaging identified a total of 112 PSMA avid metastatic lesions compared to 57 (51%) lesions on 99mTc-PSMA imaging. Eighteen out of 57 lesions were detected only on delayed 99mTc-PSMA imaging at 4 h and/or 6 h. The regional 99mTc-PSMA SPECT detected 51/83 (61.0%) lesions seen on 68Ga-PSMA PET/CT. The dosimetry results demonstrated that 99mTc-PSMA provided organs' radiation absorbed/effective doses comparable with 99mTc-PSMA imaging. CONCLUSION: Whole-body 99mTc-PSMA combined with regional SPECT/CT could be a potential alternative to 68Ga-PSMA PET for the detection of the advanced stage metastatic prostate cancer and for response evaluation to PSMA-based targeted therapies.


Asunto(s)
Isótopos de Galio , Radioisótopos de Galio , Cámaras gamma , Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Anciano , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Radiometría , Imagen de Cuerpo Entero
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