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1.
ACS Appl Bio Mater ; 7(9): 6127-6137, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39133870

RESUMO

Rapid detection and classification of pathogenic microbes for food hygiene, healthcare, environmental contamination, and chemical and biological exposures remain a major challenge due to nonavailability of fast and accurate detection methods. The delay in clinical diagnosis of the most frequent bacterial infections, particularly urinary tract infections (UTIs), which affect about half of the population at least once in their lifetime, can be fatal if not detected and treated appropriately. In this work, we have fabricated aluminum (Al) foil integrated pegylated gold nanoparticles (AuNPs) as a potential surface-enhanced Raman scattering (SERS) substrate, which is used for the detection and classification of uropathogens, namely, E. coli, S. aureus, and P. aeruginosa directly from the culture without any pretreatment. The substrate is first drop cast with bacterial pellets and then pegylated AuNPs, and the interaction of two on Al foil base gives identifiable characteristic Raman peaks with good reproducibility. With the use of chemometric methods such as principal component analysis (PCA), the Al foil-based SERS substrate offers a quick, effective detection and classification of three strains of UTI bacteria with the least bacterial concentration (105 cells mL-1) necessary for clinical diagnosis. In addition, this substrate was able to detect E. coli positive clinical samples by giving SERS fingerprint information directly from centrifuged urine samples within minutes. The stability of pegylated AuNPs provides for its application at the point of care with rapid and easy detection of uropathogens as well as the possibility of advancement in healthcare applications.


Assuntos
Alumínio , Escherichia coli , Ouro , Nanopartículas Metálicas , Polietilenoglicóis , Análise Espectral Raman , Staphylococcus aureus , Ouro/química , Nanopartículas Metálicas/química , Alumínio/química , Polietilenoglicóis/química , Escherichia coli/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Tamanho da Partícula , Propriedades de Superfície , Teste de Materiais , Materiais Biocompatíveis/química , Pseudomonas aeruginosa/isolamento & purificação , Infecções Urinárias/diagnóstico , Infecções Urinárias/microbiologia , Humanos
2.
Cureus ; 16(4): e59238, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38813298

RESUMO

INTRODUCTION: Almost a quarter of the people on earth are anemic, and most of them reside in regions of sub-Saharan Africa and South Asia. Anemia in children is linked with impaired cognitive and motor development and affects the future earning capacity. The most common cause of anemia is iron deficiency. The Indian Government has initiated multiple programs for the eradication of anemia. The prevalence of anemia has not decreased despite the improvements in the country's economy. It increased from 58.7% in 2015-16 to 67.1% in 2019-21 in children and from 50.4% in 2015-16 to 52.2% in 2019-21 in pregnant women. Maternal education, socioeconomic status, and number of children in the family are some factors that influence the prevalence of anemia. As these factors cannot be improved in a short time, we aimed to increase awareness about this issue by targeting school students from rural/semi-urban backgrounds. METHODS: This pilot study aimed at promoting school students as public health advocates in their community. Anemia Awareness Program was conducted in a local middle school in the suburban area, which was attended by 153 class eight students (72 female). Pre- and post-test questionnaires comprising 20 multiple-choice/true-false type questions were used. Pre- and post-test scores were obtained. The second part of the study was the identification of students with anemia. Blood hemoglobin levels of 127 students (58 female) were measured from venous blood samples. The students were also asked to inform their friends/relatives about anemia and to send people with symptoms of anemia to the free two-day Anemia Awareness Camp organized by the Medical College Hospital for check-ups. RESULTS: The mean post-test score (15.68/20) was much higher than the pretest score (2.99/20). Thirty-eight (25 female) out of 127 students had mild/moderate microcytic hypochromic anemia, suggesting iron deficiency. Thirty-two persons visited the free health camp to receive information from the students, of whom four had normal hemoglobin levels. CONCLUSION: This pilot study showed that physician-conducted anemia awareness programs are relatively low-cost methods to spread information among the general population in India.

3.
ACS Omega ; 9(2): 2687-2695, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38250409

RESUMO

Melamine is a chemical compound that is added to dairy products to increase the apparent protein content for higher profit margins. However, extended consumption of melamine can cause health risks. The SERS technique has proven to be an important tool for detecting small compounds, such as melamine. Here, a paper-based flexible nanoparticles (NPs)-hybrid SERS substrate was designed by drop-casting pegylated gold nanoparticles (AuNPs) on the filter papers. In SERS characterization, this substrate exhibited an enhancement factor of 108 and a limit of detection (LOD) as low as 10-8 M for Rhodamine 6G dye. Furthermore, we successfully utilized these substrates to detect the melamine spiked milk sample with an LOD as low as 0.01 ppm. This hybrid SERS substrate offers a low-cost, biocompatible, and easy-to-use fabrication for large-scale production, which may be widely used in food safety applications.

4.
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1422249

RESUMO

Abstract Objective: To assess the need for orthodontic treatment among Nepalese high school students. Material and Methods: This is a quantitative, cross-sectional descriptive study. The sample comprises 938 children (537 males and 401 females) with an age group above 14 years. The subjects were selected voluntarily from seven different schools of Kathmandu valley using a multistage sampling technique. The Index of Orthodontic Treatment Need comprises two components: Dental Health Component (DHC) and Aesthetic Component (AC). Two trained and calibrated examiners performed the oral examination. Results: On analysis of the DHC component, it was found that 21% had no need, 18.1% had mild/little need, 24.3% had moderate/borderline need, 35.8% had severe need, and 0.7% had extreme treatment need. Similarly on analysis of AC component, it was found that 33% were AC-1, 30.8% were AC-2, 7.2% were AC-3, 8.2% were AC-4, 2.1% were AC-5, 3.6% were AC-6, 1.8% were AC-7, 7.4% were AC-8, 1.8% were AC-9, and 3.9% were AC-10. Conclusion: The Index of Orthodontic Treatment Need can be used as a tool for planning dental health resources and prioritizing the treatment need of different populations (AU).


Assuntos
Humanos , Masculino , Feminino , Adolescente , Estudantes/psicologia , Saúde Bucal/educação , Índice de Necessidade de Tratamento Ortodôntico , Má Oclusão/terapia , Epidemiologia Descritiva , Estudos Transversais/métodos , Ensino Fundamental e Médio
5.
Stem Cell Rev Rep ; 17(3): 777-784, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33140233

RESUMO

Maintenance of metaphase-II (M-II) arrest in ovum is required to present itself as a right gamete for successful fertilization in mammals. Surprisingly, instability of meiotic cell cycle results in spontaneous exit from M-II arrest, chromosomal scattering and incomplete extrusion of second polar body (PB-II) without forming pronuclei so called abortive spontaneous ovum activation (SOA). It remains unclear what causes meiotic instability in freshly ovulated ovum that results in abortive SOA. We propose the involvement of various signal molecules such as reactive oxygen species (ROS), cyclic 3',5' adenosine monophosphate (cAMP) and calcium (Ca2+) in the induction of meiotic instability and thereby abortive SOA. These signal molecules through their downstream pathways modulate phosphorylation status and activity of cyclin dependent kinase (cdk1) as well as cyclin B1 level. Changes in phosphorylation status of cdk1 and its activity, dissociation and degradation of cyclin B1 destabilize maturation promoting factor (MPF). The premature MPF destabilization and defects in other cell cycle regulators possibly cause meiotic instability in ovum soon after ovulation. The meiotic instability results in a pathological condition of abortive SOA and deteriorates ovum quality. These ova are unfit for fertilization and limit reproductive outcome in several mammalian species including human. Therefore, global attention is required to identify the underlying causes in greater details in order to address the problem of meiotic instability in ova of several mammalian species icluding human. Moreover, these activated ova may be used to create parthenogenetic embryonic stem cell lines in vitro for the use in regenerative medicine.Graphical abstract.


Assuntos
Fator Promotor de Maturação , Oócitos , Animais , Cálcio/metabolismo , Feminino , Humanos , Mamíferos/metabolismo , Fator Promotor de Maturação/metabolismo , Fosforilação
6.
Eur J Pharmacol ; 883: 173293, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32663542

RESUMO

Cyclic nucleotide phosphodiesterases (PDEs) are group of enzymes responsible for the hydrolysis of cyclic adenosine 3', 5' monophosphate (cAMP) and cyclic guanosine 3', 5' monophosphate (cGMP) levels in wide variety of cell types. These PDEs are detected in encircling granulosa cells or in oocyte with in follicular microenvironment and responsible for the decrease of cAMP and cGMP levels in mammalian oocytes. A transient decrease of cAMP level initiates downstream pathways to cause spontaneous meiotic resumption from diplotene arrest and induces oocyte maturation. The nonspecific PDE inhibitors (caffeine, pentoxifylline, theophylline, IBMX etc.) as well as specific PDE inhibitors (cilostamide, milrinone, org 9935, cilostazol etc.) have been used to elevate cAMP level and inhibit meiotic resumption from diplotene arrest and oocyte maturation, ovulation, fertilization and pregnancy rates both in vivo as well as under in vitro culture conditions. The PDEs inhibitors are used as powerful experimental tools to demonstrate cyclic nucleotide mediated changes in ovarian functions and thereby fertility. Indeed, non-hormonal nature and reversible effects of nonspecific as well as specific PDE inhibitors hold promise for the development of novel therapeutic drugs for female fertility regulation.


Assuntos
Fármacos para a Fertilidade Feminina/uso terapêutico , Fertilidade/efeitos dos fármacos , Infertilidade Feminina/tratamento farmacológico , Oócitos/efeitos dos fármacos , Ovário/efeitos dos fármacos , Inibidores de Fosfodiesterase/uso terapêutico , Animais , Feminino , Humanos , Infertilidade Feminina/enzimologia , Infertilidade Feminina/fisiopatologia , Oócitos/enzimologia , Ovário/enzimologia , Ovário/fisiopatologia , Ovulação/efeitos dos fármacos , Gravidez
7.
J Biomed Sci ; 26(1): 11, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30665407

RESUMO

Stress is deeply rooted in the modern society due to limited resources and large competition to achieve the desired goal. Women are more frequently exposed to several stressors during their reproductive age that trigger generation of reactive oxygen species (ROS). Accumulation of ROS in the body causes oxidative stress (OS) and adversely affects ovarian functions. The increased OS triggers various cell death pathways in the ovary. Beside apoptosis and autophagy, OS trigger necroptosis in granulosa cell as well as in follicular oocyte. The OS could activate receptor interacting protein kinase-1(RIPK1), receptor interacting protein kinase-3 (RIPK3) and mixed lineage kinase domain-like protein (MLKL) to trigger necroptosis in mammalian ovary. The granulosa cell necroptosis may deprive follicular oocyte from nutrients, growth factors and survival factors. Under these conditions, oocyte becomes more susceptible towards OS-mediated necroptosis in the follicular oocytes. Induction of necroptosis in encircling granulosa cell and oocyte may lead to follicular atresia. Indeed, follicular atresia is one of the major events responsible for the elimination of majority of germ cells from cohort of ovary. Thus, the inhibition of necroptosis could prevent precautious germ cell depletion from ovary that may cause reproductive senescence and early menopause in several mammalian species including human.


Assuntos
Apoptose/fisiologia , Necrose/fisiopatologia , Ovário/fisiopatologia , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/efeitos adversos , Estresse Fisiológico , Animais , Feminino , Humanos
8.
J Cell Physiol ; 234(6): 8019-8027, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30341907

RESUMO

The maximum number of germ cells is present during the fetal life in mammals. Follicular atresia results in rapid depletion of germ cells from the cohort of the ovary. At the time of puberty, only a few hundred (<1%) germ cells are either culminated into oocytes or further get eliminated during the reproductive life. Although apoptosis plays a major role, necrosis as well as necroptosis, might also be involved in germ cell elimination from the mammalian ovary. Both necrosis and necroptosis show similar morphological features and are characterized by an increase in cell volume, cell membrane permeabilization, and rupture that lead to cellular demise. Necroptosis is initiated by tumor necrosis factor and operated through receptor interacting protein kinase as well as mixed lineage kinase domain-like protein. The acetylcholinesterase, cytokines, starvation, and oxidative stress play important roles in necroptosis-mediated granulosa cell death. The granulosa cell necroptosis directly or indirectly induces susceptibility toward necroptotic or apoptotic cell death in oocytes. Indeed, prevention of necrosis and necroptosis pathways using their specific inhibitors could enhance growth/differentiation factor-9 expression, improve survivability as well as the meiotic competency of oocytes, and prevent decline of reproductive potential in several mammalian species and early onset of menopause in women. This study updates the information and focuses on the possible involvement of necrosis and necroptosis in germ cell depletion from the mammalian ovary.


Assuntos
Necroptose/genética , Necrose/genética , Oócitos/crescimento & desenvolvimento , Ovário/crescimento & desenvolvimento , Animais , Apoptose/genética , Feminino , Células Germinativas/crescimento & desenvolvimento , Células Germinativas/metabolismo , Células da Granulosa/metabolismo , Humanos , Mamíferos , Oócitos/metabolismo , Ovário/metabolismo , Estresse Oxidativo/genética
9.
Cancer Genet ; 204(2): 103-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21504708

RESUMO

Hepatosplenic T-cell lymphomas (HSTCL) are rare cancers and comprise 5% of peripheral T-cell lymphomas. These well-characterized extranodal lymphomas have a disguised onset, secondary to intrasinusoidal infiltration of the spleen, liver, and bone marrow, with a rapidly progressive course that is poorly responsive to chemotherapy and often ensues in the setting of immune system suppression. We describe the clinical, immunophenotypic, cytogenetic, fluorescence in situ hybridization, and molecular analyses for T cell receptor gene rearrangement in a 21-year-old man diagnosed with HSTCL. Immunophenotypic analysis revealed negativity for CD5 as well as double negativity for CD4/CD8 mature T-cell immunophenotype, which suggested the diagnosis of hepatosplenic T-cell lymphoma. Molecular analysis confirmed a TCR gene rearrangement, thereby verifying the common T-cell origin of the present HSTCL case. Furthermore, cytogenetic analysis revealed a novel chromosomal rearrangement, t(7;15)(p22;q21). Metaphase fluorescence in situ hybridization analysis confirmed the translocation of a chromosomal segment from 15q21 to 7p22.


Assuntos
Aberrações Cromossômicas , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Linfoma de Células T/genética , Linfoma de Células T/patologia , Neoplasias Esplênicas/genética , Neoplasias Esplênicas/patologia , Genes Codificadores da Cadeia beta de Receptores de Linfócitos T , Genes Codificadores da Cadeia gama de Receptores de Linfócitos T , Humanos , Hibridização in Situ Fluorescente , Masculino , Adulto Jovem
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