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1.
World J Surg Oncol ; 22(1): 201, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080678

RESUMEN

BACKGROUND: Cross-species horizontal gene transfer (HGT) involves the transfer of genetic material between different species of organisms. In recent years, mounting evidence has emerged that cross-species HGT does take place and may play a role in the development and progression of diseases. METHODS: Transcriptomic data obtained from patients with gallbladder cancer (GBC) was assessed for the differential expression of antisense RNAs (asRNAs). The Basic Local Alignment Search Tool (BLAST) was used for cross-species analysis with viral, bacterial, fungal, and ancient human genomes to elucidate the evolutionary cross species origins of these differential asRNAs. Functional enrichment analysis and text mining were conducted and a network of asRNAs targeting mRNAs was constructed to understand the function of differential asRNAs better. RESULTS: A total of 17 differentially expressed antisense RNAs (asRNAs) were identified in gallbladder cancer tissue compared to that of normal gallbladder. BLAST analysis of 15 of these asRNAs (AFAP1-AS1, HMGA2-AS1, MNX1-AS1, SLC2A1-AS1, BBOX1-AS1, ELFN1-AS1, TRPM2-AS, DNAH17-AS1, DCST1-AS1, VPS9D1-AS1, MIR1-1HG-AS1, HAND2-AS1, PGM5P4-AS1, PGM5P3-AS1, and MAGI2-AS) showed varying degree of similarities with bacterial and viral genomes, except for UNC5B-AS1 and SOX21-AS1, which were conserved during evolution. Two of these 15 asRNAs, (VPS9D1-AS1 and SLC2A1-AS1) exhibited a high degree of similarity with viral genomes (Chikungunya virus, Human immunodeficiency virus 1, Stealth virus 1, and Zika virus) and bacterial genomes including (Staphylococcus sp., Bradyrhizobium sp., Pasteurella multocida sp., and, Klebsiella pneumoniae sp.), indicating potential HGT during evolution. CONCLUSION: The results provide novel evidence supporting the hypothesis that differentially expressed asRNAs in GBC exhibit varying sequence similarity with bacterial, viral, and ancient human genomes, indicating a potential shared evolutionary origin. These non-coding genes are enriched with methylation and were found to be associated with cancer-related pathways, including the P53 and PI3K-AKT signaling pathways, suggesting their possible involvement in tumor development.


Asunto(s)
Neoplasias de la Vesícula Biliar , Transferencia de Gen Horizontal , Humanos , Neoplasias de la Vesícula Biliar/genética , Neoplasias de la Vesícula Biliar/patología , Neoplasias de la Vesícula Biliar/virología , Carcinogénesis/genética , ARN sin Sentido/genética , Regulación Neoplásica de la Expresión Génica , Transcriptoma
2.
Artículo en Inglés | MEDLINE | ID: mdl-38757568

RESUMEN

OBJECTIVE: A pregnancy at the utero-tubal junction is a rare type of ectopic pregnancy and is associated with high maternal morbidity if it remains undetected. In the present study we discuss four cases of ectopic pregnancies at the utero-tubal junction which caused diagnostic and management dilemmas. METHODS: Four cases of early pregnancies with the gestational sac (G-sac) implanted near the utero-tubal junction are described. In case 1 this was suspected after a failed attempt at dilatation and curettage at our hospital, cases 2 and 3 presented with amenorrhea and pain abdomen and case 4 was diagnosed on first pregnancy documentation scan after frozen embryo transfer. RESULTS: As initial two-dimensional (2D) transvaginal scan (TVS) failed to diagnose the exact location of the G-sac, three-dimensional (3D) TVS helped to localize the exact location of pregnancy and subsequent individualized management. Case 1 had a partial intramural ectopic pregnancy managed by laparotomy and removal of the ectopic sac. The second and third cases were eccentric uterine pregnancies. The fourth was an interstitial ectopic pregnancy managed by a laparoscopic loop and stitch technique. CONCLUSION: This case series describes the role of 3D TVS for the evaluation of pregnancies implanted at the utero-tubal junction and individual management of eccentric intrauterine, interstitial ectopic and intramural ectopic pregnancies. A diagnostic algorithm for such types of cases and management options is discussed.

3.
J Mater Chem B ; 12(24): 5982-5993, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38809161

RESUMEN

This work aimed to manufacture Ti-28.5Nb and Ti-40.0Nb (wt%) alloys in situ via selective laser melting (SLM) from Ti and Nb elemental powders. X-ray diffraction analysis revealed complete ß-phase (cubic) in Ti-40.0Nb and a mixture of (α'' orthorhombic + ß cubic) phases in Ti-28.5Nb were formed, whereas few of the Nb particles remained only partially fused during manufacturing. The fraction of partially melted Nb particles was determined as ∼2 and ∼18% in Ti-28.5Nb and Ti-40Nb, respectively. Mechanical characterization revealed higher hardness and more strength in Ti-28.5Nb than in Ti-40.0Nb due to the presence of the α'' phase in the former. Tribocorrosion tests reveal a significantly better wear-corrosion resistance for Ti-40.0Nb, as determined from a lower total volume loss in Ti-40.0Nb (∼2 × 10-4 mm-3) than in Ti-28.5Nb (∼13 × 10-2 mm-3). The lower volume loss and better corrosion resistance behavior are attributed to the ß phase, which was dominant in Ti-40.0Nb. Cell studies reveal no toxicity for up to 7 days. Both the alloys were better at supporting cell proliferation than wrought Ti6Al4V. This study presents a route to preparing Ti-Nb alloys in situ by SLM that are promising candidates for biomedical applications.


Asunto(s)
Aleaciones , Rayos Láser , Niobio , Titanio , Aleaciones/química , Niobio/química , Titanio/química , Ensayo de Materiales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/síntesis química , Humanos , Animales , Propiedades de Superficie , Proliferación Celular/efectos de los fármacos , Ratones
4.
J Hum Genet ; 69(8): 365-372, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38664537

RESUMEN

The present prospective cohort study evaluated the prevalence of FSH-R receptor Asn680Ser and Ala307Thr among infertile Indian women and the correlation of these polymorphisms with ART outcomes. Total 804 infertile and 209 fertile controls were enrolled for FSH-R analysis. Correlation of different genotypes with ovarian reserve markers, IVF parameters, and cumulative live birth rates (CLBR) was done among women undergoing IVF. In fertile controls, at 680 position GG (Ser/Ser) was the most common genotype; but among infertile women, all the genotypes were equally distributed. There was no significant difference in ovarian response parameters, oocyte yield, and CLBR among the three genotype groups. Empty follicle syndrome (EFS) was highest in women with AA or AG type at both positions. On categorisation of unexpected poor responders according to POSEIDON stratification; GG genotype at both positions had the lowest risk ratio of low-oocyte yield in ART cycles, but these differences were not statistically significant. This is the largest study from Indian ethnicity showing GG (Ser/Ser) genotype is most common among fertile women. The effect of FSH-R genotypes is very marginal on IVF parameters and is not reflected in CLBR. More prospective data may be required on the correlation of these genotypes with genuine EFS, thus stratifying the next cycles with self or donor oocytes. Routine genetic testing of FSH-R polymorphism should not be done except in a research setting. As both 680 and 307 positions are in linkage disequilibrium, only 680 position analysis may be done in a research setting.


Asunto(s)
Infertilidad Femenina , Receptores de HFE , Adulto , Femenino , Humanos , Embarazo , Fertilización In Vitro , Genotipo , India/epidemiología , Infertilidad Femenina/genética , Infertilidad Femenina/epidemiología , Polimorfismo de Nucleótido Simple , Prevalencia , Estudios Prospectivos , Receptores de HFE/genética , Técnicas Reproductivas Asistidas
5.
J Hum Reprod Sci ; 17(1): 50-57, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38665608

RESUMEN

Background: Polycystic ovary syndrome (PCOS) women are at risk of developing diabetes, cardiovascular disease and metabolic syndrome (MetS) due to insulin resistance (IR) and hyperandrogenism (HA). Both visceral adiposity index (VAI) and lipid accumulation product (LAP) are simple outpatient department-based metric tools that have been introduced to screen PCOS women who are metabolically unhealthy and are at risk of development of MetS. Aims: The aim of the study was to evaluate VAI and LAP in women with PCOS and to correlate them with metabolic and endocrine markers. The study also assessed these parameters amongst different PCOS phenotypes and determined their usefulness to define metabolically healthy PCOS (MH-PCOS) and metabolically unhealthy PCOS (MU-PCOS). Settings and Design: The design of the study was a cross-sectional study. Materials and Methods: Two hundred PCOS women were included in the study, and all the clinical, anthropometric, hormonal, biochemical and metabolic markers were assessed. The cohort was divided into MH-PCOS and MU-PCOS by the modified National Cholesterol Education Programme criteria. VAI and LAP were calculated and correlated with clinical, endocrine and metabolic parameters. Statistical Analysis Used: Univariate and multivariate logistic regression analysis was used to study the independent role of VAI and LAP to predict MetS. Adjusted and unadjusted odds ratios were calculated. Receiver-operating characteristic (ROC) analysis was done to define cut-offs in Asian Indian women. Results: VAI and LAP had good ability to correctly discriminate MU-PCOS from MH-PCOS (area under the curve [AUC] [95% confidence interval (CI)]: 0.89 [0.82-0.95]) and (AUC [95% CI [0.81-0.92] =0.86) using ROC, respectively. The sensitivity of VAI and LAP corresponding to the optimal cut-off of ≥2.76 and ≥48.06 (Youden) was 84.09% and 79.55%, respectively. Similarly, the specificity of VAI and LAP was 85.26% and 79.49%, respectively. VAI has a positive predictive value of 61.7% (95% CI [23.7%-40.3%]) and a negative predictive value of 95% (95% CI [88%-99.1%]). LAP has a positive predictive value of 53% (95% CI [40.3%-65.4%]) and a negative predictive value of 93.3% (95% CI [87.6%-96.9%]). PCOS women having VAI ≥ 2.76 had 19.3 times ([95% CI: 6.50-57.70]) more chance of developing MetS. PCOS women having LAP (≥48.06) have 3.7 times ([95% CI: 1.35-10.60]) more odds. There was no difference between ROC curves of VAI and LAP (P = 0.32). Conclusion: VAI cut-off ≥ 2.76 and LAP with a cut-off of ≥ 48.06 may be used as markers for predicting MetS amongst PCOS women.

6.
World J Surg Oncol ; 22(1): 18, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38200568

RESUMEN

BACKGROUND: Head and neck cancer (HNC) is one of the most frequent malignancies in Asian males with a poor prognosis. Apart from well-known prognostic indicators, markers of tumor hypoxia can help us predict response to treatment and survival. METHODS: A review of the literature on the present evidence and potential clinical importance of tumor hypoxia in head and neck cancer was carried out. The data obtained from the literature search is presented as a narrative review. RESULTS: The literature shows possible associations between prognosis and low tumor oxygenation. Intermediate hypoxia biomarkers like HIF-1, GLUT-1, miRNA, and lactate, can help in predicting the response to therapy and survival as their altered expression is related to prognosis. CONCLUSIONS: Hypoxia is common in HNC and can be detected by use of biomarkers. The tumors that show expression of hypoxia biomarkers have poor prognosis except for patients with human papilloma virus-associated or VHL-associated cancers. Therapeutic targeting of hypoxia is emerging; however, it is still in its nascent stage, with increasing clinical trials hypoxia is set to emerge as an attractive therapeutic target in HNC.


Asunto(s)
Neoplasias de la Boca , Hipoxia Tumoral , Masculino , Humanos , Hipoxia , Ácido Láctico , Biomarcadores
7.
Cancers (Basel) ; 16(1)2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38201650

RESUMEN

The benefit of aspirin on cancer survival is debated. Data from randomized clinical trials and cohort studies are discordant, although a meta-analysis shows a clear survival advantage when aspirin is added to the standard of care. However, the mechanism by which aspirin improves cancer survival is not clear. A PubMed search was carried out to identify articles reporting genes and pathways that are associated with aspirin and cancer survival. Gene ontology and pathway enrichment analysis was carried out using web-based tools. Gene-gene and protein-protein interactions were evaluated. Crosstalk between pathways was identified and plotted. Forty-one genes were identified and classified into primary genes (PTGS2 and PTGES2), genes regulating cellular proliferation, interleukin and cytokine genes, and DNA repair genes. The network analysis showed a rich gene-gene and protein-protein interaction between these genes and proteins. Pathway enrichment showed the interleukin and cellular transduction pathways as the main pathways involved in aspirin-related survival, in addition to DNA repair, autophagy, extracellular matrix, and apoptosis pathways. Crosstalk of PTGS2 with EGFR, JAK/AKT, TP53, interleukin/TNFα/NFκB, GSK3B/BRCA/PARP, CXCR/MUC1, and WNT/CTNNB pathways was identified. The results of the present study demonstrate that aspirin improves cancer survival by the interplay of 41 genes through a complex mechanism. PTGS2 is the primary target of aspirin and impacts cancer survival through six primary pathways: the interleukin pathway, extracellular matrix pathway, signal transduction pathway, apoptosis pathway, autophagy pathway, and DNA repair pathway.

8.
J Reprod Infertil ; 24(2): 117-131, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37547574

RESUMEN

Background: The purpose of the current study was to evaluate patient-oriented strategies encompassing individualized oocyte number (POSEIDON) criteria, validate stratification of low prognosis women, and prognosticate their reproductive potential in terms of cumulative live birth rate (CLBR) in Indian women. Methods: Out of 4048 women who underwent IVF/ICSI, 3287 women met the criteria for final evaluation of CLBR. They criteria were divided into (a) group 1a as cases with <4 oocytes retrieved and 1b with 4-9 oocytes retrieved; (b) group 2a as cases with <4 oocytes retrieved and 2b with 4-9 oocytes retrieved; (c) group 3 (<35 years, AMH <1.2 ng/ml, AFC <5); and (d) group 4 (≥35 years, AMH <1.2 ng/ml, AFC <5). Non-POSEIDON group was sub-divided into normo-responders (10-20 oocytes) and hyper-responder (>20 oocytes). Results: Overall CLBR was two-fold lower in POSEIDON group as compared to non-POSEIDON group (p<0.001). For every one-year increase in the age, the odds of CLBR decreased by 4% (OR 0.96, CI 0.93-0.99) in POSEIDON group and by 5% (OR 0.95, CI 0.92-0.98) in non-POSEIDON group. For every unit increase in number of oocytes retrieved, the odds of CLBR increased by 1.22 times (OR1.22, CI 1.16-1.28) in POSEIDON group and by 1.08 times (OR 1.08, CI 1.05-1.11) in non-POSEIDON group. Among POSEIDON groups, the highest values in CLBR belonged to group 1b followed by 3, 2b, 4, 1a, and 2a. Conclusion: POSEIDON stratification of low-prognosis women undergoing IVF may be considered valid to prognosticate and counsel women undergoing IVF. Prospective studies will strengthen its validity among different ethnic populations.

9.
J Hum Reprod Sci ; 16(1): 79-86, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37305779

RESUMEN

This case report highlights the diagnostic dilemma and therapeutic challenges encountered while managing adolescent girls with progressive dysmenorrhoea and management of Robert's uterus. Two girls aged 20 years and 13 years presented with severe progressive dysmenorrhoea. In the first case, laparoscopy revealed juvenile cystic adenomyoma (JCA) of 3 cm × 3 cm on the left side anteroinferior to the round ligament. Laparoscopic resection of the lesion was done, and histopathology revealed features of adenomyosis. In the second case, there was a globular enlargement of the right half of the uterine body with round ligament and adnexa attached to the lesion (Robert's uterus). In view of severe symptoms, complete resection of the lesion and partial resection of hemi-uterus was done, followed by myometrial defect closure. Both cases were initially diagnosed as JCA, and the final diagnosis was made on laparoscopy. Both girls had complete symptomatic relief from the next menstrual cycle and have been under follow-up for 24 months and 18 months, respectively. Due to the rarity of conditions, Robert's uterus and JCA are usually misdiagnosed with each other or with other Mullerian anomalies such as a non-communicating unicornuate uterus. Radiologists and clinicians should be aware of these different pathologies causing similar symptoms. Understanding the pathology, early diagnosis, timely referral and correct surgical procedure are emphasised to improve reproductive outcomes.

10.
World J Surg Oncol ; 21(1): 173, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37287033

RESUMEN

A 60-year-old man presented with complaints of abdominal pain and melena. Patient had a history of colon cancer 16 years back and had undergone right hemi colectomy for microsatellite instability (MSI) negative, mismatch repair (MMR) stable, T2N0 disease with no mutations on next-generation sequencing (NGS). Investigations revealed a second primary in stomach (intestinal type of adenocarcinoma) with no recurrent lesions in colon or distant metastasis. He was started on CapOx with Bevacizumab and developed gastric outlet obstruction. Total gastrectomy with D2 lymphadenectomy and Roux-en-Y oesophageao-jejunal pouch anastomosis was done. The histopathology showed intestinal type of adenocarcinoma with pT3N2 disease. NGS showed 3 novel mutations in KMT2A, LTK, and MST1R gene. The pathway enrichment analysis and Gene Ontology were carried out, followed by the construction of protein-protein interaction network to discover associations among the genes. The results suggested that these mutations have not been reported in gastric cancer earlier and despite not having a direct pathway of carcinogenesis they probably act through modulation of host of miRNA's. Further studies are needed to investigate the role of KMT2A, LTK, and MST1R gene in gastric carcinogenesis.


Asunto(s)
Adenocarcinoma , Neoplasias del Colon , Neoplasias Primarias Secundarias , Neoplasias Gástricas , Masculino , Humanos , Persona de Mediana Edad , Neoplasias Gástricas/genética , Neoplasias Gástricas/cirugía , Neoplasias Gástricas/patología , Gastrectomía/métodos , Neoplasias del Colon/genética , Neoplasias del Colon/cirugía , Anastomosis en-Y de Roux , Neoplasias Primarias Secundarias/cirugía , Adenocarcinoma/genética , Adenocarcinoma/cirugía , Carcinogénesis
12.
Reprod Sci ; 30(8): 2554-2562, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36862325

RESUMEN

Anti-Mullerian hormone (AMH) is one of the direct indicators of follicular pool but no standard cutoff has been defined for diagnosis of polycystic ovary syndrome (PCOS). The present study evaluated the serum AMH levels among different PCOS phenotypes and correlated the AMH levels with clinical, hormonal, and metabolic parameters among Indian PCOS women. Mean serum AMH was 12.39 ± 5.3ng/mL in PCOS cohort and 3.83 ± 1.5 ng/mL in non-PCOS cohort (P < 0.01). Out of 608 PCOS women, 273 (44.9%) women belonged to phenotype A, 230 (37.8%) women were phenotype D. Phenotypes C and B were 12.17% and 5.10% respectively. Among those with the highest AMH group (AMH>20ng/ml; 8.05%), majority belonged to phenotype A. Menstrual cycle length, serum testosterone, fasting total cholesterol levels, and follicle number per ovary had positive correlation with serum anti-Mullerian levels (P < 0.05). AMH cutoff for the diagnosis of PCOS was calculated as ≥ 6.06 ng/mL on ROC analysis with sensitivity and specificity of 91.45% and 90.71% respectively. The study shows high serum AMH levels in PCOS are associated with worse clinical, endocrinological, and metabolic parameters. These levels may be used to counsel patients regarding treatment response, help in individualized management and prediction of reproductive and long-term metabolic outcomes.


Asunto(s)
Síndrome del Ovario Poliquístico , Humanos , Femenino , Masculino , Síndrome del Ovario Poliquístico/metabolismo , Hormona Antimülleriana , Folículo Ovárico/metabolismo , Fenotipo
13.
Mol Biol Rep ; 49(11): 10153-10163, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36018415

RESUMEN

BACKGROUND: Gallbladder Cancer (GBC) is one of the most common cancers of the biliary tract and the third commonest gastrointestinal (GI) malignancy worldwide. The disease is characterized by the late presentation and poor outcome despite treatment, and hence, newer therapies and targets need to be identified. METHODS: The current study investigated various functionally enriched pathways in GBC pathogenesis involving the genes identified through Next Generation Sequencing (NGS) in a hospital-based cohort. The Pathway enrichment analysis and Gene Ontology (GO) were carried out after NGS, followed by the construction of the protein-protein interaction (PPI) network to discover associations among the genes. RESULTS: Of the thirty-three patients with GBC who were screened through next-generation sequencing (NGS), 27somatic mutations were identified. These mutations involved a total of 14 genes. The p53 and KRAS were commonly found to be mutated, while mutations in other genes were seen in one case each, the mean number of mutations were 1.2, and maximum mutation in a single case (eight) was seen in one case. The bioinformatics analysis identified MAP kinase, PI3K-AKT, EGF/EGFR, and Focal Adhesion PI3K-AKT-mTOR signaling pathways and cross-talk between these. CONCLUSION: The results suggest that the complex crosstalk between the mTOR, MAPK, and multiple interacting cell signaling cascades can promote GBC progression, and hence, mTOR-MAPK targeted treatment will be an attractive option.


Asunto(s)
Neoplasias de la Vesícula Biliar , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Biología Computacional/métodos , Sirolimus , Proteínas Proto-Oncogénicas c-akt/genética , Fosfatidilinositol 3-Quinasas/genética , Proteínas Quinasas Activadas por Mitógenos/genética , Neoplasias de la Vesícula Biliar/genética , Neoplasias de la Vesícula Biliar/patología , Serina-Treonina Quinasas TOR/genética , Mutación/genética , Carcinogénesis , Hospitales
14.
Mol Biol Rep ; 49(7): 6395-6403, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35469389

RESUMEN

BACKGROUND: Gallbladder cancer (GBC) represents a wide geographical diversity as well as heterogeneity in clinical and genomic landscape. There seems to be little progress in the development of diagnostic biomarkers, targeted therapies or individualized approaches to GBC management. In this study, we investigated the whole transcriptome profile of GBC patients using RNA sequencing and identified key genes and pathways associated with gallbladder cancer using bioinformatics. METHODOLOGY: A total of 10 cases of GBC were collected and sequenced. The raw reads of the gallbladder sample was compared with the gallbladder normal control (SRA Database ID: ERX288537: HPA RNA-seq normal tissues gallbladder). Using Gene ontology analysis the differentially expressed genes were categorized into the biological pathway, cellular component, and molecular function. Pathway enrichment analyses, protein-protein interaction, transcription factor and miRNA interaction that regulate the expression of hub genes were conducted using bioinformatics tool. RESULTS: A total of 954 differentially expressed mRNA transcripts were identified, including overexpression of REG4, TMEM238, S100A2, LYPD2, and KRT17, as well as underexpressed genes like CCKAR, IGSF10, CHRM2, CRISP3, and FGF19. Enrichment analysis showed the metabolic pathways to be the top five cancer pathways in gallbladder carcinogenesis besides PI3k-Akt signalling pathway, cAMP signalling pathway, miRNAs in cancer, and cell adhesion profile of GBC. CONCLUSIONS: CCKAR, CDKN2A and LRRK2 were found to be most involved genes in its progression and development through different regulatory pathways. Further, most of the genes were significantly involved in PI3k-Akt, Wnt and hedgehog signaling pathways which have a key role in gallbladder cancer development.


Asunto(s)
Neoplasias de la Vesícula Biliar , MicroARNs , Neoplasias de la Vesícula Biliar/genética , Neoplasias de la Vesícula Biliar/metabolismo , Proteínas Hedgehog/genética , Humanos , MicroARNs/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/genética , Transcriptoma/genética
15.
ACS Omega ; 7(10): 8506-8517, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35309459

RESUMEN

Laser powder bed fusion (L-PBF) was attempted here to additively manufacture a new generation orthopedic ß titanium alloy Ti-35Nb-7Zr-5Ta toward engineering patient-specific implants. Parts were fabricated using four different values of energy density (ED) input ranging from 46.6 to 54.8 J/mm3 through predefined laser beam parameters from prealloyed powders. All the conditions yielded parts of >98.5% of theoretical density. X-ray microcomputed tomography analyses of the fabricated parts revealed minimal imperfections with enhanced densification at a higher ED input. X-ray diffraction analysis indicated a marginally larger d-spacing and tensile residual stress at the highest ED input that is ascribed to the steeper temperature gradients. Cellular to columnar dendritic transformation was observed at the highest ED along with an increase in the size of the solidified features indicating the synergetic effects of the temperature gradient and solidification growth rate. Density measurements indicated ≈99.5% theoretical density achieved for an ED of 50.0 J/mm3. The maximum tensile strength of ≈660 MPa was obtained at an ED of 54.8 J/mm3 through the formation of the columnar dendritic substructure. High ductility ranging from 25 to 30% was observed in all the fabricated parts irrespective of ED. The assessment of cytocompatibility in vitro indicated good attachment and proliferation of osteoblasts on the fabricated samples that were similar to the cell response on commercially pure titanium, confirming the potential of the additively manufactured Ti-35Nb-7Zr-5Ta as a suitable material for biomedical applications. Taken together, these results demonstrate the feasibility of L-PBF of Ti-35Nb-7Zr-5Ta for potentially engineering patient-specific orthopedic implants.

16.
Int J Biol Macromol ; 202: 644-656, 2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-35066028

RESUMEN

Three-dimensional (3D) bioprinting based on digital light processing (DLP) offers unique opportunities to prepare scaffolds that mimic the architecture and biomechanical properties of human tissues. Limited availability of biocompatible and biodegradable bioinks amenable for DLP-bioprinting is an impediment in this field. This study presents a bioink prepared from silk fibroin (SF) tailored for DLP bioprinting. Photocurable methacrylated-SF (SF-MA) was synthesized with 67.3% of methacrylation. Physical characterization of rheological and mechanical properties revealed that the 3D printed hydrogels of SF-MA (spanning from 10 to 25 wt%) exhibit bone tissue-like viscoelastic behavior and compressive modulus ranging from ≈12 kPa to ≈96 kPa. The gels exhibited favorable degradation (≈48 to 91% in 21 days). This SF-MA bioink afforded the printing of complex structures, with high precision. Pre-osteoblasts were successfully encapsulated in 3D bioprinted SF-MA hydrogels with high viability. 15% SF-MA DLP bioprinted hydrogels efficiently supported cell proliferation with favorable cell morphology and cytoskeletal organization. A progressive increase in cell-mediated calcium deposition up to 14 days confirmed the ability of the gels to drive osteogenesis, which was further augmented by soluble induction factors. This work demonstrates the potential of silk fibroin-derived bioinks for DLP-based 3D bioprinting of scaffolds for tissue engineering.


Asunto(s)
Bioimpresión , Fibroínas , Bioimpresión/métodos , Huesos , Fibroínas/química , Humanos , Hidrogeles/química , Impresión Tridimensional , Seda/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química
17.
ACS Mater Au ; 2(2): 132-142, 2022 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-36855763

RESUMEN

Additive manufacturing (AM) is being widely explored for engineering biomedical implants. The microstructure and surface finish of additively manufactured parts are typically different from wrought parts and exhibit limited bioactivity despite the other advantages of using AM for fabrication. The aim of this study was to enhance the bioactivity of selective laser melted Ti-6Al-4V alloy by electrophoretic deposition of nanohydroxyapatite (nanoHAp) coatings. The deposition parameters were systematically investigated after the coatings were deposited on the as-manufactured surface or after polishing the surface of the additively-manufactured sample. The surfaces were coated with nanoHAp suspended in either ethanol or butanol using different voltages (10, 30, or 50 V) for varied deposition times. The formation of the nanoHAp coating was confirmed by Fourier-transform infrared spectroscopy and X-ray diffraction. Microstructural analysis revealed that several conditions of the coating led to crack formation. The coated samples were subsequently heat-treated to improve the integrity of the coating. Heat treatment led to crack formation in several conditions due to thermal shrinkages. Coatings prepared using butanol were more uniform and had minimal cracks compared with the use of ethanol. Nanoindentation confirmed good stability and integrity of the nanoHAP coatings on the as-manufactured and polished surfaces. The coating on the as-manufactured sample exhibited higher hardness and lower elastic modulus as compared with the coating on the polished sample. In vitro study revealed that the nanoHAp coating markedly enhanced the attachment, proliferation, and differentiation of preosteoblasts on the alloy. These results provide a viable route to enhancing the bioactivity through deposition of nanoHAp with important implications for engineering additively manufactured orthopedic and dental implants suitable for better clinical performance.

18.
ACS Chem Neurosci ; 12(22): 4319-4335, 2021 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-34747594

RESUMEN

Stress-induced dopaminergic (DAergic) neuronal death in the midbrain region is the primary cause of Parkinson's disease (PD). Following the discovery of l-dopa, multiple drugs have been developed to improve the lifestyle of PD patients; however, none have been suitable for clinical use due to their multiple side effects. Tinospora cordifolia has been used in traditional medicines to treat neurodegenerative diseases. Previously, we reported the neuroprotective role of Tc via inhibition of NF-κB-associated proinflammatory cytokines against MPTP-intoxicated Parkinsonian mice. In the present study, we investigated the neuroprotective molecular mechanism of Tc in a rotenone (ROT)-intoxicated mouse model, using a proteomics approach. Mice were pretreated with Tc extract by oral administration, followed by ROT intoxication. Behavioral tests were performed to check motor functions of mice. Protein was isolated, and label-free quantification (LFQ) was carried out to identify differentially expressed protein (DEP) in control vs PD and PD vs treatment groups. Results were validated by qRT-PCR with the expression of target genes correlating with the proteomics data. In this study, we report 800 DEPs in control vs PD and 133 in PD vs treatment groups. In silico tools demonstrate significant enrichment of biochemical and molecular pathways with DEPs, which are known to be important for PD progression including mitochondrial gene expression, PD pathways, TGF-ß signaling, and Alzheimer's disease. This study provides novel insights into the PD progression as well as new therapeutic targets. More importantly, it demonstrates that Tc can exert therapeutic effects by regulating multiple pathways, resulting in neuroprotection.


Asunto(s)
Fármacos Neuroprotectores , Tinospora , Animales , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas , Humanos , Ratones , Ratones Endogámicos C57BL , Fármacos Neuroprotectores/farmacología , Proteómica
19.
Biomed Mater ; 16(4)2021 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-34030150

RESUMEN

Magnesium and its alloys have the potential to serve as a revolutionary class of biodegradable materials, specifically in the field of degradable implants for orthopedics. However, the corrosion rate of commercially pure magnesium is high and does not match the rate of regeneration of bone tissues. In this work, magnesium alloys containing zinc and cerium, either alone or in combination, were investigated and compared with commercially-pure magnesium as biomaterials. The microstructure, mechanical properties, corrosion resistance, and response of osteoblastsin vitrowere systematically assessed. Results reveal that alloying with Ce results in grain refinement and weakening of texture. The tensile test revealed that the ternary alloy offered the best combination of elastic modulus (41.1 ± 0.5 GPa), tensile strength (234.5 ± 4.5 MPa), and elongation to break (17.1 ± 0.4%). The ternary alloy was also the most resistant to corrosion (current of 0.85 ± 0.05 × 10-4A cm-2) in simulated body fluid than the other alloys. The response of MC3T3-E1 cellsin vitrorevealed that the ternary alloy imparts minimal cytotoxicity. Interestingly, the ternary alloy was highly efficient in supporting osteogenic differentiation, as revealed by the expression of alkaline phosphatase and calcium deposition. In summary, the extruded Mg alloy containing both Zn and Ce exhibits a combination of mechanical properties, corrosion resistance, and cell response that is highly attractive for engineering biodegradable orthopedic implants.


Asunto(s)
Materiales Biocompatibles , Cerio , Osteogénesis/efectos de los fármacos , Zinc , Implantes Absorbibles , Aleaciones/química , Aleaciones/farmacología , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cerio/química , Cerio/farmacología , Corrosión , Módulo de Elasticidad/efectos de los fármacos , Magnesio/metabolismo , Ensayo de Materiales , Ratones , Osteoblastos/efectos de los fármacos , Zinc/química , Zinc/farmacología
20.
ACS Appl Bio Mater ; 4(5): 4328-4344, 2021 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35006845

RESUMEN

We report a significant improvement of adipose-derived mesenchymal stem cells' (ADMSCs) biocompatibility and proliferation on hierarchically patterned porous honey-incorporated silk fibroin scaffolds fabricated using a combination of soft lithography and freeze-drying techniques. Parametric variations show enhanced surface roughness, swelling, and degradation rate with good pore interconnectivity, porosity, and mechanical strength for soft-lithographically fabricated biomimetic microdome arrays on the 2% honey silk fibroin scaffold (PHSF2) as compared to its other variants, which eventually made PHSF2 more comparable to the native environment required for stem cell adhesion and proliferation. PHSF2 also exhibits sustained honey release with remarkable antibacterial efficacy against methicillin-resistant Staphylococcus aureus (MRSA). Honey incorporation (biochemical cue) influences microdome structural features, that is, biophysical cues (height, width, and periodicity), which further allows ADMSCs pseudopods (filopodia) to grasp the microdomes for efficient cell-cell communication and cell-matrix interaction and regulates ADMSCs behavior by altering their cytoskeletal rearrangement and thereby increases the cellular spreading area and cell sheet formation. The synergistic effect of biochemical (honey) and biophysical (patterns) cues on ADMSCs studied by the nitro blue tetrazolium assay and DCFDA fluorescence spectroscopy reveals limited free radical generation within cells. Molecular expression studies show a decrease in p53 and p21 expressions validating ADMSCs senescence inhibition, which is further correlated with a decrease in cellular senescence-associated ß galactosidase activity. We also show that an increase in CDH1 and CK19 molecular expressions along with an increase in SOX9, RUNX2, and PPARγ molecular expressions supported by PHSF2 justify the substrate's efficacy of underpinning mesenchymal to epithelial transition and multilineage trans-differentiation. This work highlights the fabrication of a naturally healing nutraceutical (honey)-embedded patterned porous stand-alone tool with the potential to be used as smart stem cells delivering regenerative healing implant.


Asunto(s)
Materiales Biocompatibles/farmacología , Fibroínas/farmacología , Células Madre Mesenquimatosas/efectos de los fármacos , Animales , Materiales Biocompatibles/química , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Senescencia Celular/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Fibroínas/química , Ensayo de Materiales , Ratones , Tamaño de la Partícula , Porosidad , Propiedades de Superficie , Andamios del Tejido/química
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