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1.
Food Chem ; 445: 138787, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38382254

RESUMEN

In this study, a straightforward electrochemical aptasensor was developed to detect sulfadimethoxine (SDM). It included a glassy carbon electrode decorated by boron nitride quantum dots (BNQDs) and aptamer-functionalized nanoporous carbon (APT/CZ). CZ was first synthesized by calcinating a zeolitic imidazolate framework (ZIF-8). Then, the electroactive dye methylene blue (MB) was entrapped inside its pores. By attaching aptamer to the CZ surface, APT/CZ acted as a bioguard, which prevented the MB release. Therefore, the electrochemical signal of the entrapped MB was high in the absence of SDM. Introducing SDM caused the conformation of aptamers to change, and a large number of MB was released, which was removed by washing. Therefore, the detection strategy was done based on the change in the electrochemical signal intensity of MB. The aptasensor was applied to detect SDM at a concentration range of 10-17 to 10-7 M with a detection limit of 3.6 × 10-18 M.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Nanoporos , Sulfadimetoxina , Carbono , Técnicas Electroquímicas , Aptámeros de Nucleótidos/química , Límite de Detección , Oro/química , Azul de Metileno/química
2.
Iran J Basic Med Sci ; 27(1): 24-30, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38164481

RESUMEN

Objectives: Tuberculosis (TB), a contagious disease caused by Mycobacterium tuberculosis (M. tuberculosis), remains a health problem worldwide and this infection has the highest mortality rate among bacterial infections. Current studies suggest that intranasal administration of new TB vaccines could enhance the immunogenicity of M. tuberculosis antigens. Hence, we aim to evaluate the protective efficacy and immunogenicity of HspX/EsxS fusion protein of M. tuberculosis along with ISCOMATRIX and PLUSCOM nano-adjuvants and MPLA through intranasal administration in a mice model. Materials and Methods: In the present study, the recombinant fusion protein was expressed in Escherichia coli and purified and used to prepare different nanoparticle formulations in combination with ISCOMATRIX and PLUSCOM nano-adjuvants and MPLA. Mice were intranasally vaccinated with each formulation three times at an interval of 2 weeks. Three weeks after the final vaccination, IFN-γ, IL-4. IL-17, and TGF-ß concentrations in the supernatant of cultured splenocytes of vaccinated mice as well as serum titers of IgG1 and IgG2a and sIgA titers in nasal lavage were determined. Results: According to obtained results, intranasally vaccinated mice with formulations containing ISCOMATRIX and PLUSCOM nano-adjuvants and MPLA could effectively induce IFN-γ and sIgA responses. Moreover, both HspX/EsxS/ISCOMATRIX/MPLA and HspX/EsxS/PLUSCOM/MPLA and their BCG booster formulation could strongly stimulate the immune system and enhance the immunogenicity of M. tuberculosis antigens. Conclusion: The results demonstrate the potential of HspX/EsxS-fused protein in combination with ISCOMATRIX, PLUSCOM, and MPLA after nasal administration in enhancing the immune response against M. tuberculosis antigens. Both nanoparticles were good adjuvants in order to promote the immunogenicity of TB-fused antigens. So, nasal immunization with these formulations, could induce immune responses and be considered a new TB vaccine or a BCG booster.

3.
Mikrochim Acta ; 191(1): 36, 2023 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-38108890

RESUMEN

A highly sensitive colorimetric method (glycan-based nano(e)zyme) was developed for sensitive and rapid detection of the SARS-CoV-2 virus based on N-acetyl neuraminic acid (sialic acid)-functionalized gold nanoparticles (SA-Au NZs). A number of techniques were used to characterize the prepared nanomaterials including XRD, FT-IR, UV-vis, DLS, and TEM. DLS analysis indicates an average hydrodynamic size of 34 nm, whereas TEM analysis indicates an average particle size of 15.78 nm. This observation confirms that water interacts with nanoparticle surfaces, resulting in a large hydrodynamic diameter. The peroxidase-like activity of SA-Au NZs was examined with SARS-CoV-2 and influenza viruses (influenza A (H1N1), influenza A (H3N2), and influenza B). UV-visible spectroscopy was used to monitor and record the results, as well as naked eye detection (photographs). SA-Au NZs exhibit a change in color from light red to purple when SARS-CoV-2 is present, and they exhibit a redshift in their spectrum. N-acetyl neuraminic acid interacts with SARS-CoV-2 spike glycoprotein, confirming its ability to bind glycans. As a result, SA-Au NZs can detect COVID-19 with sensitivity and specificity of over 95% and 98%, respectively. This method was approved by testing saliva samples from 533 suspected individuals at Ghaem Hospital of Mashhad, Mashhad, Iran. Sensitivity and specificity were calculated by comparing the results with the definitive results. The positive results were accompanied by a color change from bright red to purple within five minutes. Statistical analysis was performed based on variables such as age, gender, smoking, diabetes, hypertension, and lung involvement. In clinical trials, it was demonstrated that this method can be used to diagnose SARS-CoV-2 in a variety of places, such as medical centers, hospitals, airports, universities, and schools.


Asunto(s)
COVID-19 , Subtipo H1N1 del Virus de la Influenza A , Gripe Humana , Nanopartículas del Metal , Humanos , SARS-CoV-2 , COVID-19/diagnóstico , Oro , Subtipo H3N2 del Virus de la Influenza A , Saliva , Espectroscopía Infrarroja por Transformada de Fourier
4.
Iran J Microbiol ; 15(6): 796-802, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38156307

RESUMEN

Background and Objectives: Group A Rotavirus (RVA) is the most important causative agent of acute diarrheal disease in pediatrics 5 years and below. This study aimed to determine the distribution of circulating RVA in Mashhad, Iran to develop health improvement strategies and vaccine decision making. Materials and Methods: A total of 106 fecal specimens were collected from children admitted to Akbar and Dr. Sheikh referral pediatric hospitals of Mashhad City during the December 2020 to March 2021 and December 2021 to March 2022. All specimens were tested for specific bacterial, parasitic, and amoebic infections. Negative samples were analyzed for RVA infections using the RT-PCR method. Results: RVA was detected in 31.3% of the specimens, indicating no statistical significance in gender distribution or between fall and winter positivity rates. The number of RVA-positive specimens increased following age increasing in the range of 1 to 60 months. Conclusion: Today, acute diarrheal disease (ADD) is still caused mostly by Rotavirus infections in pediatrics in Mashhad. Comprehensive studies are needed to determine the genetic diversity of circulating Rotavirus strains in this era.

5.
Curr Pharm Des ; 29(38): 3018-3039, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37990895

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is a highly widespread malignancy and ranks as the second most common cause of cancer-related mortality. OBJECTIVE: Cancer patients, including those with CRC, who undergo chemotherapy, are often treated with platinum- based anticancer drugs such as oxaliplatin (OXA). Nevertheless, the administration of OXA is associated with a range of gastrointestinal problems, neuropathy, and respiratory tract infections. Hence, it is necessary to devise a potential strategy that can effectively tackle these aforementioned challenges. The use of nanocarriers has shown great potential in cancer treatment due to their ability to minimize side effects, target drugs directly to cancer cells, and improve drug efficacy. Furthermore, numerous studies have been published regarding the therapeutic efficacy of nanoparticles in the management of colorectal cancer. METHODS: In this review, we present the most relevant nanostructures used for OXA encapsulation in recent years, such as solid lipid nanoparticles, liposomes, polysaccharides, proteins, silica nanoparticles, metal nanoparticles, and synthetic polymer-carriers. Additionally, the paper provides a summary of the disadvantages and limits associated with nanoparticles. RESULTS: The use of different carriers for the delivery of oxaliplatin increased the efficiency and reduced the side effects of the drug. It has been observed that the majority of research investigations have focused on liposomes and polysaccharides. CONCLUSION: This potentially auspicious method has the potential to enhance results and enhance the quality of life for cancer patients undergoing chemotherapy. However, additional investigation is required to ascertain the most suitable medium for the transportation of oxaliplatin and to assess its efficacy through clinical trials.


Asunto(s)
Antineoplásicos , Neoplasias Colorrectales , Nanopartículas , Humanos , Oxaliplatino/uso terapéutico , Oxaliplatino/farmacología , Liposomas/uso terapéutico , Neoplasias Colorrectales/metabolismo , Calidad de Vida , Antineoplásicos/farmacología , Nanopartículas/química , Polisacáridos/uso terapéutico
6.
Mikrochim Acta ; 190(8): 293, 2023 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-37458847

RESUMEN

A novel genosensor was developed for rotavirus specific cDNA sequence detection. The genosensor was comprised of hierarchical flower-like gold nanostructures, MXene, and polypyrrole (HFGNs/MXene/PPY) nanocomposite as a signal amplification tag, specific antisense ssDNA oligonucleotide as a recognition bioelement, and methylene blue (MB) as a redox marker. The morphological and electrochemical features of the biosensor were first tested and optimized and the high performance of the platform was confirmed in terms of sensitivity and reproducibility. Then, 20 rotavirus RNA isolated from clinical and cell-cultured samples (10 positive and 10 negative confirmed by RT-PCR and electrophoresis methods) were evaluated by the genosensor. The analysis results revealed that the genosensor is able to differentiate successfully between the positive and negative control groups. The developed genosensor for rotavirus RNA detection presented an excellent limit of detection of ∼ 0.8 aM and a determination  range of  10-18 and 10-7 M. In addition, the ssDNA/HFGNs/MXene/PPY/GCE showed high selectivity and long-term stability of ~ 24 days. Therefore, this novel genosensor would be of great benefit for the clinical diagnosis of rotavirus.


Asunto(s)
Nanocompuestos , Rotavirus , Polímeros/química , Pirroles/química , Rotavirus/genética , Oro/química , Reproducibilidad de los Resultados , Nanocompuestos/química , ADN de Cadena Simple/genética , ARN
7.
Talanta ; 265: 124804, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37329753

RESUMEN

Since the rapid spread of the SARS-CoV-2 (2019), the need for early diagnostic techniques to control this pandemic has been highlighted. Diagnostic methods based on virus replication, such as RT-PCR, are exceedingly time-consuming and expensive. As a result, a rapid and accurate electrochemical test which is both available and cost-effective was designed in this study. MXene nanosheets (Ti3C2Tx) and carbon platinum (Pt/C) were employed to amplify the signal of this biosensor upon hybridization reaction of the DNA probe and the virus's specific oligonucleotide target in the RdRp gene region. By the differential pulse voltammetry (DPV) technique, the calibration curve was obtained for the target with varying concentrations ranging from 1 aM to 100 nM. Due to the increase in the concentration of the oligonucleotide target, the signal of DPV increased with a positive slope and a correlation coefficient of 0.9977. Therefore, at least a limit of detection (LOD) was obtained 0.4 aM. Furthermore, the specificity and sensitivity of the sensors were evaluated with 192 clinical samples with positive and negative RT-PCR tests, which revealed 100% accuracy and sensitivity, 97.87% specificity and limit of quantification (LOQ) of 60 copies/mL. Besides, various matrices such as saliva, nasopharyngeal swabs, and serum were assessed for detecting SARS-CoV-2 infection by the developed biosensor, indicating that this biosensor has the potential to be used for rapid Covid-19 test detection.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Nanocompuestos , Humanos , COVID-19/diagnóstico , SARS-CoV-2/genética , ARN , Técnicas Biosensibles/métodos , Oligonucleótidos , ADN
8.
Future Microbiol ; 18: 215-223, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-37129534

RESUMEN

Aim: This study aimed to investigate the role of AmpC enzymes in carbapenem resistance among AmpC/extended-spectrum ß-lactamase (ESBL)-producing clinical isolates of Escherichia coli and Klebsiella spp. Methods: Fifty-six bacterial strains that were AmpC producers were examined. The antibiotic susceptibility test was performed by the disk diffusion and E-test. The prevalence of the plasmid carbapenemase was determined using PCR. Results: The resistance to meropenem in the AmpC+/ESBL+ group was 64%, higher than that reported for the AmpC-/ESBL+ group. Ten isolates of the carbapenem-resistant AmpC producers were negative for carbapenemase-encoding genes. Conclusion: Carbapenem resistance among AmpC-producing isolates with negative results for carbapenemase-encoding genes potentially demonstrates the role of AmpC enzymes among these isolates.


Asunto(s)
Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Escherichia coli , Humanos , Klebsiella/genética , Antibacterianos/farmacología , Infecciones por Escherichia coli/microbiología , Klebsiella pneumoniae/genética , Escherichia coli , beta-Lactamasas/genética , Proteínas Bacterianas/genética , Carbapenémicos/farmacología , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Pruebas de Sensibilidad Microbiana
9.
Iran Biomed J ; 27(2 & 3): 152-7, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-37070598

RESUMEN

Background: Considering the high prevalence and clinical importance of herpes simplex virus (HSV) infection worldwide, we aimed to evaluate the seroprevalence of HSV-1 and HSV-2 in a population aged between 15 and 35 years in Mashhad, Iran. Methods: This cross-sectional study was conducted on 916 cases composed of 288 (31.4%) men and 628 (68.6%) women. Using ELISA method, the presence of IgM and IgG antibodies against HSV-1 and HSV-2 was assessed. Results: Among the population studied, 681 (74.3%) cases were positive for anti-HSV antibodies, while 235 (25.7%) cases were negative. Moreover, no IgMs were found and all positive subjects had IgG antibodies. Age (p < 0.001), occupation (p < 0.001), education (p = 0.006), smoking (p = 0.029), and BMI (p = 0.004) demonstrated a significant association with HSV-1 and HSV-2 infection. Conclusion: Our study indicates a high seroprevalence of HSV infection; however, there was no cases positive for IgM antibodies, suggesting the high prevalence of latent infection.


Asunto(s)
Herpes Genital , Herpes Simple , Herpesvirus Humano 1 , Masculino , Humanos , Femenino , Adolescente , Adulto Joven , Adulto , Herpes Genital/epidemiología , Estudios Seroepidemiológicos , Estudios Transversales , Herpes Simple/epidemiología , Herpesvirus Humano 2 , Anticuerpos Antivirales , Inmunoglobulina G
10.
Appl Biochem Biotechnol ; 195(8): 5120-5135, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36847984

RESUMEN

Silver nanoparticles (AgNPs) have gained great interest because of their specific and distinct properties. Chemically synthesized AgNPs (cAgNPs) are often unsuitable for medical applications due to requiring toxic and hazardous solvents. Thus, green synthesis of AgNPs (gAgNPs) using safe and nontoxic substances has attracted particular focus. The current study investigated the potential of Salvadora persica and Caccinia macranthera extracts in the synthesis of CmNPs and SpNPs, respectively. Aqueous extracts of Salvadora persica and Caccinia macranthera were prepared and taken as reducing and stabilizing agents through gAgNPs synthesis. The antimicrobial effects of gAgNPs against susceptible and antibiotic-resistant bacterial strains and their toxicity effects on L929 fibroblast normal cells were evaluated. TEM images and particle size distribution analysis showed that the CmNPs and SpNPs have average sizes of 14.8 nm and 39.4 nm, respectively. The XRD confirms the crystalline nature and purity of both CmNPs and SpNPs. FTIR results demonstrate the involvement of the biologically active substances of both plant extracts in the green synthesis of AgNPs. According to MIC and MBC results, higher antimicrobial effects were seen for CmNPs with a smaller size than SpNPs. In addition, CmNPs and SpNPs were much less cytotoxic when examined against a normal cell relative to cAgNPs. Based on high efficacy in controlling antibiotic-resistant pathogens without detrimental adverse effects, CmNPs may have the capacity to be used in medicine as imaging, drug carrier, and antibacterial and anticancer agents.


Asunto(s)
Nanopartículas del Metal , Salvadoraceae , Antibacterianos/química , Salvadoraceae/química , Plata/farmacología , Plata/química , Nanopartículas del Metal/química , Bacterias , Extractos Vegetales/farmacología , Extractos Vegetales/química , Pruebas de Sensibilidad Microbiana , Tecnología Química Verde , Espectroscopía Infrarroja por Transformada de Fourier
11.
Iran J Basic Med Sci ; 25(11): 1299-1307, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36474565

RESUMEN

Objectives: To address a highly mutable pathogen, mutations must be evaluated. SARS-CoV-2 involves changing infectivity, mortality, and treatment and vaccination susceptibility resulting from mutations. Materials and Methods: We investigated the Asian and worldwide samples of amino-acid sequences (AASs) for envelope (E), membrane (M), nucleocapsid (N), and spike (S) proteins from the announcement of the new coronavirus 2019 (COVID-19) up to January 2022. Sequence alignment to the Wuhan-2019 virus permits tracking mutations in Asian and global samples. Furthermore, we explored the evolutionary tendencies of structural protein mutations and compared the results between Asia and the globe. Results: The mutation analyses indicated that 5.81%, 70.63%, 26.59%, and 3.36% of Asian S, E, M, and N samples did not display any mutation. Additionally, the most relative mutations among the S, E, M, and N AASs occurred in the regions of 508 to 635 AA, 7 to 14 AA, 66 to 88 AA, and 164 to 205 AA in both Asian and total samples. D614G, T9I, I82T, and R203M were inferred as the most frequent mutations in S, E, M, and N AASs. Timeline research showed that substitution mutation in the location of 614 among Asian and total S AASs was detected from January 2020. Conclusion: N protein was the most non-conserved protein, and the most prevalent mutations in S, E, M, and N AASs were D614G, T9I, I82T, and R203M. Screening structural protein mutations is a robust approach for developing drugs, vaccines, and more specific diagnostic tools.

12.
Virol J ; 19(1): 220, 2022 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-36528612

RESUMEN

BACKGROUND: Emergence of new variants mainly variants of concerns (VOC) is caused by mutations in main structural proteins of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Therefore, we aimed to investigate the mutations among structural proteins of SARS-CoV-2 globally. METHODS: We analyzed samples of amino-acid sequences (AASs) for envelope (E), membrane (M), nucleocapsid (N), and spike (S) proteins from the declaration of the coronavirus 2019 (COVID-19) as pandemic to January 2022. The presence and location of mutations were then investigated by aligning the sequences to the reference sequence and categorizing them based on frequency and continent. Finally, the related human genes with the viral structural genes were discovered, and their interactions were reported. RESULTS: The results indicated that the most relative mutations among the E, M, N, and S AASs occurred in the regions of 7 to 14, 66 to 88, 164 to 205, and 508 to 635 AAs, respectively. The most frequent mutations in E, M, N, and S proteins were T9I, I82T, R203M/R203K, and D614G. D614G was the most frequent mutation in all six geographical areas. Following D614G, L18F, A222V, E484K, and N501Y, respectively, were ranked as the most frequent mutations in S protein globally. Besides, A-kinase Anchoring Protein 8 Like (AKAP8L) was shown as the linkage unit between M, E, and E cluster genes. CONCLUSION: Screening the structural protein mutations can help scientists introduce better drug and vaccine development strategies.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Mutación , Glicoproteína de la Espiga del Coronavirus/genética , Secuencia de Aminoácidos , Nucleocápside
13.
Curr Microbiol ; 79(9): 257, 2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35852629

RESUMEN

The effective management of multidrug-resistant tuberculosis (MDR-TB) and the need for rapid and accurate screening of rifampin (RIF) and isoniazid (INH)-resistant Mycobacterium tuberculosis (Mtb) isolates are the most fundamental and difficult challenges facing the global TB control. The present study aimed to compare the diagnostic accuracy of high-resolution melting-curve analysis (HRMA) in comparison to multiplex allele-specific PCR (MAS-PCR) and xpert MTB/RIF as well as the conventional drug-susceptibility test (DST) and gene sequencing for the detection of INH and RIF resistance in the Mtb isolates. In the present study, a total of 431 Mtb isolates including 11 MDR (%2.55), 7 INH resistance (%1.62), two RIF resistance (%0.46), and 411 sensitive isolates were phenotypically confirmed. HRMA assay identified katG gene mutations and the mabA-inhA promoter region in 15 of 18 INH-resistant samples and rpoB gene mutations were successfully evaluated in 11 out of 13 RIF-resistant samples. The sensitivity and specificity of the HRMA method were 83.3% and 98.8% for INH and 84.6% and 99% for RIF, respectively. The most common mutation in RIF-resistance-determining region (RRDR) occurred at codon 531 (TCG → TTG)(84.6%) and then at codon 513 (CAA → GTA)(7.6%) and 526 (CAC → TAC) (7.6%), which resulted in the amino-acid changes. Also, 88.8% of INH-resistant samples had mutations in the katG gene and the mabA-inhA promoter region, of which the highest mutation occurred at codon 315 (AGC → ACC) of the katG gene. In conclusion, all these results indicated that the sensitivity and specificity of the HRM method were increased when the katG gene and the mabA-inhA promoter region were used as a target.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Antituberculosos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/farmacología , Codón , Humanos , Isoniazida/farmacología , Pruebas de Sensibilidad Microbiana , Reacción en Cadena de la Polimerasa Multiplex , Mutación , Rifampin/farmacología , Esputo/microbiología , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Tuberculosis Resistente a Múltiples Medicamentos/genética , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
14.
Biosens Bioelectron ; 207: 114209, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35339072

RESUMEN

The sudden increase of the COVID-19 outbreak and its continued growth with mutations in various forms has created a global health crisis as well as devastating social and economic effects over the past two years. In this study, a screen-printed carbon electrode reinforced with boron nitride quantum dots/flower-like gold nanostructures (BNQDs/FGNs/SPCE) and functionalized by highly specific antisense DNA oligonucleotide presents an alternative and promising solution for targeting SARS-CoV-2 RNA without nucleic acid amplification. The platform was tested on 120 SARS-CoV-2 RNA isolated from real clinical samples (60 positive and 60 negative confirmed by conventional RT-PCR method). Based on obtained quantitative results and statistical analysis (box-diagram, cutoff value, receiver operating characteristic curve, and t-test), the biosensor revealed a significant difference between the two positive and negative groups with 100% sensitivity and 100% specificity. To evaluate the quantitation capacity and detection limit of the biosensor for clinical trials, the detection performance of the biosensor for continuously diluted RNA isolated from SARS-CoV-2-confirmed patients was compared to those obtained by RT-PCR, demonstrating that the detection limit of the biosensor is lower than or comparable to that of RT-PCR. The ssDNA/BNQDs/FGNs/SPCE showed negligible cross-reactivity with RNA fragments isolated from Influenza A (IAV) clinical samples and also remained stable for up to 14 days. In conclusion, the fabricated biosensor may serve as a promising tool for point-of-care applications.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Nanoestructuras , Puntos Cuánticos , Técnicas Biosensibles/métodos , Compuestos de Boro , COVID-19/diagnóstico , Oro , Humanos , ARN Viral/genética , SARS-CoV-2/genética , Sensibilidad y Especificidad
15.
Iran J Pathol ; 17(1): 8-14, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35096083

RESUMEN

BACKGROUND & OBJECTIVE: Polyomaviruses types BK and JC and Cytomegalovirus (CMV) have been shown to be related to kidney transplantation complications. This study aimed to assess the prevalence of these viruses in patients receiving kidney transplantation. METHODS: This cross-sectional study was performed on 40 kidney transplant recipients and 44 donors. Urine samples were used for the extraction of viral DNA. The prevalence of JC and BK viruses and their viral loads were determined by real-time polymerase chain reaction. RESULTS: JC and BK viruses were identified in 31% and 92.3% of all subjects, respectively. The frequency of JC and BK cases was not statistically different between the recipient and donor groups (P>0.05). All patients in the donor group and 96.8% of the recipients were positive for CMV IgG antibody. The mean viral load of BK in donors and recipients was 4.5×1010 and 3.3×1011 copies, respectively. The mean viral load of JC was 8.6×107 copies in donors and 2.9×108 copies in recipients. The distribution of BKV was significantly higher in recipients than donors (P=0.001), while no difference was observed between the two studied groups for JCV. CONCLUSION: This study showed a relatively high prevalence of BK and JC viruria in both renal transplant donors and recipients. The viral load for BKV, but not JCV, was higher in recipients than in donors.

16.
Talanta ; 238(Pt 2): 123049, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34801906

RESUMEN

Mycobacterium simiae has been reported to be the most prevalent species of Nontuberculous mycobacteria (NTM) in many countries. As both phenotypic and molecular detection of M. simiae and other NTMs have limitations, finding an accurate, fast, and low-cost diagnostic method is critical for the management of infections. Here, we report the development of a new type of label-free electrochemical biosensor using a gold electrode decorated with l-cysteine/PAMAM dendrimer for specific targeting of M. simiae ITS sequence. DNA hybridization was monitored by measuring changes in the free guanine electrical signal with changing ssDNA target concentrations by differential pulse voltammetry (DPV) method. Response surface methodology (RSM) was applied for the optimization of variables affecting biosensor response. Under optimal conditions, the biosensor revealed a wide linear range from 10-14 M to 10-6 M and a detection limit of 1.40 fM. The fabricated biosensor showed an excellent selectivity to M. simiae in the presence of other similar pathogenic bacteria. Moreover, experimental results confirmed that this biosensor exhibited great precision and high reproducibility, hence provides a low-cost, label-free, and faster detection analysis, representing a novel strategy in detecting other NTMs.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , ADN , Pruebas Diagnósticas de Rutina , Oro , Mycobacterium , Micobacterias no Tuberculosas , Reproducibilidad de los Resultados
17.
Biotechnol Appl Biochem ; 69(3): 1121-1147, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33987922

RESUMEN

Metal phosphides, especially aluminum phosphide, and phosphine (PH3 ) are widely used as insecticides and rodenticides for protection of grains during process of storage and transportation. The main reason of poisoning with this compound is related to the conscious ingestion of salts or accidental inhalation of PH3 . So the early and accurate diagnosis of poisoning can significantly help to the effective clinical treatment or recognition of death cause. PH3 is somewhat unstable due to reaction with oxygen or hemoglobin leading to formation of oxy-acids phosphorous. Here, we critically reviewed the literature introducing the quantitative and qualitative methods for the detection of metal phosphides, PH3 , and its products. This study obviously demonstrates that during past years, different diagnosis methods have been remarkably progressed. Head-space gas chromatography and confirmatory colorimetric methods have been as the most popular techniques. Also, the gas sensors are a promising method that must be more progressed.


Asunto(s)
Insecticidas , Rodenticidas
18.
Talanta ; 226: 122099, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33676656

RESUMEN

An important issue in the prognosis of tuberculosis (TB) is a short period between correct diagnosis and start the suitable antibiotic therapy. So, a rapid and valid method for detection of Mycobacterium tuberculosis (M. tb) complex is considered as a necessity. Herein, a rapid, low-cost, and PCR-free DNA biosensor was developed based on multi-walled carbon nanotubes (MWCNTs), polypyrrole (PPy), and hydroxyapatite nanoparticles (HAPNPs) for highly sensitive and specific recognition of M.tb. The biosensor consisted of M.tb ssDNA probe covalently attached to the HANPs/PPy/MWCNTs/GCE surface that hybridized to a complementary target sequence to form a duplex DNA. The M.tb target recognition was based on the oxidation signal of the electroactive Methylene Blue (MB) on the surface of the modified GCE using differential pulse voltammetry (DPV) method. It is worth to mention that for the first time Plackett-Burman (PB) screening design and response surface method (RSM) based on central composite design (CCD) was applied as a powerful and an efficient approach to find optimal conditions for maximum M.tb biosensor performance leading to simplicity and rapidity of operation. The proposed DNA biosensor exhibits a wide detection range from 0.25 to 200.0 nM with a low detection limit of 0.141 nM. The performance of designed biosensor for clinical diagnosis and practical applications was revealed through hybridization between DNA probe-modified GCE and extracted DNA from sputum clinical samples.


Asunto(s)
Técnicas Biosensibles , Mycobacterium tuberculosis , Nanocompuestos , Nanotubos de Carbono , ADN/genética , Técnicas Electroquímicas , Mycobacterium tuberculosis/genética , Polímeros , Pirroles
19.
Clin Case Rep ; 9(3): 1146-1149, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33768798

RESUMEN

Closer attention should be paid to vitamin D status in patients with mycobacterial diseases.

20.
Microb Pathog ; 154: 104842, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33762199

RESUMEN

BACKGROUND: Tuberculosis (TB), caused by Mycobacterium tuberculosis (M. tuberculosis), is one of the most common and dangerous infectious diseases in the world. Despite vaccination with BCG, it is still considered as a major health problem. Therefore, design and production of an effective novel vaccine against TB is necessary. Our aim was to evaluate immunogenicity of HspX/EsxS fusion protein of M. tuberculosis along with ISCOMATRIX, PLUSCOM nano-adjuvants and MPLA through the subcutaneous route in mice model. METHODS: HspX/EsxS fused protein of M. tuberculosis was cloned, expressed and purified in the prokaryotic system. ISCOMATRIX and PLUSCOM nano-adjuvants were prepared by film hydration method. Subcutaneous immunization of BALB/c mice was performed by different formulations. IFN-γ, IL-4, IL-17 and TGF-ß cytokines levels as well as serum IgG1, IgG2a. RESULTS: Our results showed that subcutaneous administration of mice with HspX/EsxS along with three adjuvants, ISCOMATRIX, PLUSCOM and MPLA increased immunogenicity of multi-stage fusion protein of M. tuberculosis. Additionally, HspX/EsxS protein + ISCOMATRIX or + PLUSCOM nano-adjuvants induced stronger Th1, IgG2a and IgG1 immune responses compared to MPLA adjuvant. Totally, HspX/EsxS/ISCOMATRIX/MPLA, HspX/EsxS/PLUSCOM/MPLA and two BCG booster groups could significantly induce higher Th1 and IgG2a immune responses. CONCLUSION: With regard to ability of ISCOMATRIX, PLUSCOM and MPLA adjuvants to increase immunogenicity of HspX/EsxS protein through induction of IFN-γ and IgG2a immune responses, it seems that these adjuvants and especially ISCOMATRIX and PLUSCOM, could also improve BCG efficacy as a BCG booster.


Asunto(s)
Mycobacterium tuberculosis , Vacunas contra la Tuberculosis , Adyuvantes Inmunológicos , Animales , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Colesterol , Modelos Animales de Enfermedad , Combinación de Medicamentos , Ratones , Ratones Endogámicos BALB C , Mycobacterium tuberculosis/genética , Fosfolípidos , Saponinas
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