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1.
Small ; : e2402266, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38847571

RESUMEN

This work reports a novel 3D printed grid reservoir-integrated mesoporous carbon coordinated silicon oxycarbide hybrid composite (3DP-MPC-SiOC) to establish the zincophile interphase for controlling the dendrite formation. The customized 3D printed grid patterned structure inhibits Zn dendrite growth and achieves long-term stability with reduced voltage polarization due to homogeneous electric field distribution. The hybrid composite consisting of SiOC interpenetrated within carbon constructs a high zinc nucleation interphase, hence promoting uniform Zn2+ deposition and enhancing ionic diffusion with dendrite-free growth and a reduced nucleation energy barrier. As a result, the 3DP-MPC-SiOC@Zn symmetrical cell affords a highly reversible Zn plating/stripping and dendrite-free structure over 198 h with an ultra-low voltage polarization. These inspiring performances endow the 3DP anode with a 3DP-VO cathode as a full battery, which shows a retention capacity of 78.8 mAh g-1 (Coulombic efficiency: 94.04%) at 0.1 A g-1 and a large energy density of 41 Wh kg-1 at a power density of 1.2 W kg-1 (based on the total mass of electrode) after 120 cycles. This newly developed 3D printing of hybrid composite as an electrode is straightforward and scalable and provides a novel concept for realizing dendrite-free and stable rechargeable Zn-ion batteries.

2.
Mod Pathol ; 37(2): 100396, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38043790

RESUMEN

Sarcomatoid transformation occurs in ∼8% of chromophobe renal cell carcinoma (chRCC) and is associated with aggressive clinical behavior. In recent years, several studies have identified genomic, transcriptomic, and epigenomic correlates of aggressive behavior in chRCC; however, the molecular mechanisms associated with sarcomatoid transformation remain incompletely understood. In this study, we analyzed paired conventional and sarcomatoid histologic components of individual chRCC to elucidate the genomic alterations that underlie sarcomatoid transformation in this tumor type. Massively parallel sequencing was performed on paired (conventional and sarcomatoid) components from 8 chRCCs. All cases harbored TP53 variants (87.5% showing TP53 variants in both components and 12.5% only in the sarcomatoid component). Intratumor comparisons revealed that TP53 variants were concordant in 71% and discordant in 29% of cases. Additional recurrent single-nucleotide variants were found in RB1 (37.5% of cases) and PTEN (25% of cases), with the remaining single-nucleotide variants detected in these tumors (PBRM1, NF1, and ASXL1) being nonrecurrent. Copy number variant analysis showed the characteristic pattern of chromosomal losses associated with chRCC (1, 2, 6, 10, 13, 17, and 21) in the conventional histologic components only. Interestingly, the sarcomatoid components of these tumors demonstrated widespread loss of heterozygosity but lacked the above chromosomal losses, likely as a consequence of whole-genome duplication/imbalanced chromosomal duplication events. Overall, the findings suggest that TP53 variants followed by whole-genome duplication/imbalanced chromosomal duplication events underlie sarcomatoid transformation in chRCC.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Sarcoma , Humanos , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Neoplasias Renales/genética , Neoplasias Renales/patología , Duplicación Cromosómica , Sarcoma/genética , Aberraciones Cromosómicas , Pérdida de Heterocigocidad , Nucleótidos
3.
Mod Pathol ; 37(7): 100513, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38763421

RESUMEN

Postchemotherapy postpubertal-type yolk sac tumors (YST) with glandular and solid phenotypes are aggressive and commonly resistant to systemic chemotherapy. These neoplasms show morphologic features that significantly overlap with those of somatic carcinomas with "enteroblastic" or "fetal" phenotype (the preferred terminology depends on the site of origin). They often present as late or very late recurrences, and their diagnosis is challenging because they frequently affect patients in an age group at risk for carcinomas of somatic origin. Recently, we incidentally identified examples of postchemotherapy glandular and solid YST with "enteroblastic" phenotypes and nuclear expression of beta-catenin, prompting us to further evaluate the prevalence of this phenomenon. We found nuclear expression of beta-catenin in 10 (29%) of 34 such tumors. A subset of cases with nuclear beta-catenin expression was further analyzed with a DNA sequencing panel (n = 6) and fluorescence in situ hybridization for isochromosome 12p [i(12p); n = 5]. Sequencing identified exon 3 CTNNB1 variants in 3 (50%) of 6 analyzed cases, and fluorescence in situ hybridization was positive for i(12p) in 5 of 5 cases. In conclusion, a significant subset of postchemotherapy YST with glandular or solid architecture and "enteroblastic" phenotype demonstrates beta-catenin alterations, suggesting that activation of Wnt signaling may play a role in the progression of these neoplasms. Moreover, nuclear beta-catenin expression in these tumors represents a potential diagnostic pitfall given that carcinomas of true somatic origin with overlapping morphology may also be positive for this marker.


Asunto(s)
Tumor del Seno Endodérmico , beta Catenina , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Tumor del Seno Endodérmico/patología , Tumor del Seno Endodérmico/tratamiento farmacológico , Tumor del Seno Endodérmico/genética , Tumor del Seno Endodérmico/metabolismo , Femenino , Masculino , Hibridación Fluorescente in Situ , Niño , Preescolar , Adolescente , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/análisis , Adulto , Adulto Joven , Lactante , Fenotipo
4.
Histopathology ; 85(1): 182-189, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38566342

RESUMEN

CONTEXT: Carcinomas found in urinary diversion specimens are uncommon, particularly new primary tumours. New primary tumours primarily occur when the large intestine is utilised, whereas the occurrence is infrequent with the use of the ileum. These tumours include both the recurrence of primary malignancy or the development of a new primary malignancy originating from the small intestine. DESIGN: A search was performed within the pathology laboratory system to identify cases of malignancies involving ileal conduit/reconstruction from 2002 to 2022. Data on demographics, clinical details, pathology and management was recorded. RESULTS: A total of 13 male patients, with a mean age of 67 years (range = 49-81 years) were included in the study. The initial procedure performed included cystoprostatectomy (n = 10, including one case with right nephroureterectomy) and cystectomy (n = 3, including one case for bladder exstrophy) for initial diagnoses including urothelial carcinoma (n = 11; conventional, 6; sarcomatoid, 1; glandular 1; plasmacytoid, 1; micropapillary, 2) and adenocarcinoma (n = 1). The initial management included radical surgery with neoadjuvant chemotherapy/immunotherapy (n = 1), adjuvant chemotherapy (n = 3), intravesical adjuvant BCG (n = 2) and intravesical adjuvant chemotherapy (n = 1). Malignancies in ileal conduit or orthotopic ileal neobladder included recurrent urothelial carcinoma (n = 10) and new secondary adenocarcinomas (n = 3), which developed as early as 3 months (usually recurrence) and up to 13, 33 and 45 years (new primary malignancy) following primary resection. CONCLUSIONS: Utilising the ileum as conduit/neobladder presents a viable alternative for urinary diversion with a reduced malignancy risk compared to using a segment of the large intestine. However, there remains a potential for malignancy, either tumour recurrence or a new primary malignancy. In our study, tumour recurrence occurred up to 4 years following the initial diagnosis and the development of a new primary malignancy occurred up to 45 years after the initial diagnosis. Consequently, it is crucial to prioritise long-term follow-up for these patients undergoing this procedure.


Asunto(s)
Neoplasias de la Vejiga Urinaria , Derivación Urinaria , Humanos , Masculino , Persona de Mediana Edad , Anciano , Derivación Urinaria/métodos , Derivación Urinaria/efectos adversos , Neoplasias de la Vejiga Urinaria/cirugía , Neoplasias de la Vejiga Urinaria/patología , Anciano de 80 o más Años , Cistectomía/métodos , Íleon/patología , Íleon/cirugía , Carcinoma de Células Transicionales/patología , Carcinoma de Células Transicionales/cirugía , Prostatectomía
5.
Histopathology ; 84(7): 1192-1198, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38409850

RESUMEN

BACKGROUND: Carcinomas of the seminal vesicle are exceedingly rare, with a limited number of cases described in the literature. Reported cases span a relatively wide morphological spectrum, and their genomic features remain unexplored. DESIGN: In this study, we interrogated five primary epithelial neoplasms of the seminal vesicle using a targeted DNA sequencing platform (OncoPanel, 447 genes). RESULTS: The tumours included one adenocarcinoma with intestinal phenotype presenting after external beam radiation (for prostatic adenocarcinoma), one carcinoma with Müllerian-type clear cell phenotype, two mucinous tumours resembling low-grade mucinous neoplasms of the appendix (LAMN) and one mucinous cystadenoma. The post-radiation mucinous adenocarcinoma had genomic findings consistent with bi-allelic inactivation of TP53, as well as multiple copy-number changes with regional and chromosomal arm-level copy-number losses. The Müllerian-type clear cell carcinoma exhibited a complex copy-number profile with numerous regional and arm-level copy-number changes, as well as focal amplification events, including copy-number gain of 8q and amplification of a region within 20q13. Both low-grade mucinous tumours resembling LAMN harboured hot-spot gain-of-function KRAS variants (p.G12V and p.G13D) as the only genomic alteration. No genomic alterations were detected inthe lesion diagnosed as mucinous cystadenoma. CONCLUSION: Our results suggest that primary low-grade mucinous neoplasms of the seminal vesicle may represent a distinct entity equivalent to appendiceal counterparts, driven by gain-of-function variants of RAS GTPases. The remaining tumours showed genomic features that closely resembled those of neoplasms with comparable phenotypes and/or biological characteristics arising in other sites, suggesting that they could be managed similarly, with special considerations related to their anatomical location.


Asunto(s)
Neoplasias Quísticas, Mucinosas y Serosas , Neoplasias Glandulares y Epiteliales , Vesículas Seminales , Humanos , Masculino , Adulto , Anciano , Adulto Joven , Persona de Mediana Edad , Proteínas Proto-Oncogénicas p21(ras)/genética , Vesículas Seminales/patología , Neoplasias Glandulares y Epiteliales/genética , Neoplasias Glandulares y Epiteliales/patología , Adenocarcinoma/genética , Adenocarcinoma/patología , Cistoadenoma Mucinoso/genética , Cistoadenoma Mucinoso/patología , Neoplasias Quísticas, Mucinosas y Serosas/genética , Neoplasias Quísticas, Mucinosas y Serosas/patología
6.
Histopathology ; 85(1): 75-80, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38530207

RESUMEN

BACKGROUND: Testicular Leydig cell tumours (LCTs) are the most common type of sex cord-stromal tumour in men, representing 1%-3% of all testicular neoplasms. Among testicular sex cord-stromal tumours, CTNNB1 mutations and nuclear expression of ß-catenin have been typically associated with Sertoli cell tumour. Recent genomic analyses have shown that CTNNB1 variants are also identified in a subset of LCTs; however, the frequency and clinicopathologic associations of ß-catenin alterations remain incompletely understood in this tumour type. METHODS: In this study, we evaluated 32 LCTs (five malignant/metastasizing, 27 nonmetastasizing) using ß-catenin immunohistochemistry and DNA sequencing. RESULTS: Immunohistochemistry revealed focal or multifocal nuclear ß-catenin expression in 47% of the tumours. Diffuse nuclear ß-catenin expression (in >50% of the tumour cells) was not detected in any of the cases analysed herein. Comparison of ß-catenin-positive and ß-catenin-negative cases did not show significant differences in the frequency of adverse histopathologic findings or malignant clinical behaviour. DNA sequencing performed de novo on a subset of seven cases revealed the presence of exon 3 CTNNB1 variants in four of them (4/7, 57%), with variant allele frequencies (VAF) ranging from 7 to 33%. Two additional ß-catenin-positive cases that had been sequenced as part of a previous study harboured exon 3 CTNNB1 variants at VAF of 28% and 7%, respectively. CONCLUSION: These results demonstrate that ß-catenin alterations are relatively common in LCT, most likely occurring as subclonal events that are not enriched in cases with aggressive features. Further studies are needed to clarify the oncogenic role of ß-catenin in this tumour type.


Asunto(s)
Inmunohistoquímica , Tumor de Células de Leydig , Neoplasias Testiculares , beta Catenina , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Masculino , Neoplasias Testiculares/patología , Neoplasias Testiculares/genética , Neoplasias Testiculares/metabolismo , Tumor de Células de Leydig/patología , Tumor de Células de Leydig/metabolismo , Tumor de Células de Leydig/genética , Adulto , Persona de Mediana Edad , Anciano , Adulto Joven , Adolescente , Mutación , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo
7.
Adv Anat Pathol ; 31(3): 206-214, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38525515

RESUMEN

The current WHO classification of testicular germ cell tumors is based on the pathogenesis of the tumors driven by different genomic events. The germ cell neoplasia in situ is the precursor lesion for all malignant germ cell tumors. The current understanding of pathogenesis is that the developmental and environmental factors with the erasure of parental genomic imprinting lead to the development of abnormal gonocytes that settle in the "spermatogonial Niche" in seminiferous tubules. The abnormal primordial germ cells in the seminiferous tubules give rise to pre-GCNIS cells under the influence of TPSY and OCT4 genes. The whole genome duplication events give rise to germ cell neoplasia in situ, which further acquires alterations in 12p along with NRAS and KRAS mutations to produce seminoma. A subset of seminomas acquires KIT mutation and does not differentiate further. The remaining KIT-stable seminomas differentiate to nonseminomatous GCTs after obtaining recurrent chromosomal losses, epigenetic modification, and posttranscriptional regulation by multiple genes. Nonseminomatous germ cell tumors also develop directly from differentiated germ cell neoplasia in situ. TP53 pathway with downstream drivers may give rise to somatic-type malignancies of GCT. The GCTs are remarkably sensitive to cisplatin-based combination chemotherapy; however, resistance to cisplatin develops in up to 8% of tumors and appears to be driven by TP53/MDM2 gene mutations. Serum and Plasma miRNAs show promise in diagnosing, managing, and following up on these tumors. The mechanisms underlying the development of most tumors have been elucidated; however, additional studies are required to pinpoint the events directing specific characteristics. Advances in identifying specific molecular markers have been seen recently and may be adopted as gold standards in the future.


Asunto(s)
Neoplasias de Células Germinales y Embrionarias , Seminoma , Neoplasias Testiculares , Masculino , Humanos , Seminoma/metabolismo , Cisplatino , Neoplasias Testiculares/patología , Neoplasias de Células Germinales y Embrionarias/genética
8.
Adv Anat Pathol ; 31(2): 126-135, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38053410

RESUMEN

Testicular sex cord-stromal tumors (TSCSTs) are relatively rare, representing ~5% of testicular neoplasms overall. Historically, TSCSTs have been classified into 3 major entities: Leydig cell tumor, Sertoli cell tumor, and granulosa cell tumor. In recent years, immunophenotypic and molecular analyses have led to a more detailed understanding of the biological and genomic features of these neoplasms, resulting in the description of new entities, some of which have been included in the latest WHO classification. This review summarizes novel histopathologic, clinical, and molecular findings that may lead to a reappraisal of established concepts and help improve the diagnosis and clinical management of TSCSTs in the coming years.


Asunto(s)
Neoplasias Ováricas , Tumor de Células de Sertoli , Tumores de los Cordones Sexuales y Estroma de las Gónadas , Neoplasias Testiculares , Masculino , Humanos , Femenino , Tumores de los Cordones Sexuales y Estroma de las Gónadas/diagnóstico , Tumores de los Cordones Sexuales y Estroma de las Gónadas/patología , Neoplasias Testiculares/genética , Tumor de Células de Sertoli/diagnóstico , Tumor de Células de Sertoli/genética , Tumor de Células de Sertoli/patología , Diagnóstico Diferencial , Neoplasias Ováricas/diagnóstico
9.
J Fluoresc ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39042354

RESUMEN

The fluorescence behavior of pyranine in anionic micellar system of sodium dodecyl sulphate was studied in the presence of selected amines. The amines included cyclopropylamine (CPA), ethylenediamine (EDA), benzylamine (BA), dibutylamine (DBA), cyclohexylamine (CHA), and polyethylenediamine (PEDA). All the studied amines quenched the intensity of pyranine. Study was performed in 0.05 M and 0.1 M SDS. The thermodynamic parameters were determined in order to understand the quenching of pyranine by the studied amines. Change in Gibbs free energy and quenching was found higher in 0.05 M SDS concentration and was found lower when SDS concentration was increased to 0.1 M SDS. Pyranine quenching by the amines studied were treated with an extended Stern-Volmer equation that produced the Stern-Volmer constant ([Formula: see text]). Binding constant (Kb), number of binding stoichiometry (n) and Gibbs free energy change (ΔGbinding) were found higher for lower surfactant concentration as compare to higher surfactant concentration. More negative (-ve) the Gibbs free energies more will be the quenching, higher will be the sensitivity and vice versa. The Gibbs free energies for all the studied amines were found in the order as cyclopropylamine > ethylenediamine > benzylamine > dibutylamine > cyclohexylamine > polyethylenediamine. Fluorescence quenching of pyranine by amines in aqueous SDS is reproducible and is useful for the determination of amines in environmental samples.

10.
Environ Res ; 258: 119419, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38879107

RESUMEN

Nano-zerovalent iron (nZVI) is a promising material for the removal of both organic and inorganic pollutants from contaminated water. This study investigates the potential of a novel composite of nZVI on a polymer-derived supporting ceramic (nZVI-PDC) synthesized via the liquid-phase reduction method for the simultaneous adsorption and Fenton-type reduction of bromate anion (BrO3-) in water. The nZVI nanoparticles were effectively anchored onto the PDC by impregnating high-yield carbon in a ferrous sulfate solution. The PDC facilitated the uniform dispersion of nZVI nanoparticles due to its multiple active sites distributed within mesocarbon cavities. The developed nZVI-PDC composite exhibited a high specific surface area of 837 m2 g-1 and an ordered mesoporous structure with a pore volume of 0.37 cm3 g-1. As an adsorbent, the nZVI-PDC composite exhibited a maximum adsorption capacity (qe) of 842 mg g-1 and a partition coefficient (KH) of 10.2 mg g-1 µM-1, as calculated by the pseudo-second-order model. As a catalyst, the composite demonstrated a reaction kinetic rate of 43.5 µmol g-1 h-1 within 6 h at pH 4, using a dosage of 60 mg L-1 nZVI-PDC and a concentration of 0.8 mmol L-1 H2O2. Comparatively, PDC exhibited a qe of 408 mg g-1, KH of 1.67 mg g-1 µM-1, and a reaction rate of 20.8 µmol g-1 h-1, while nZVI showed a qe of 456 mg g-1, KH of 2.30 mg g-1 µM-1, and a reaction rate of 27.2 µmol g-1 h-1. The modelling indicated that the nZVI-PDC composite followed pseudo-second-order kinetics. The remarkable removal efficiency of the nZVI-PDC composite was attributed to the synergistic effects between PDC and nZVI, where PDC facilitated charge transfer, promoting Fe2+ generation and the Fe3+/Fe2+ cycle. Overall, this work introduces a promising adsorption technology for the efficient removal of BrO3- from contaminated aqueous solutions, highlighting the significant potential of the nZVI-PDC composite in water purification applications.


Asunto(s)
Bromatos , Cerámica , Hierro , Contaminantes Químicos del Agua , Hierro/química , Adsorción , Contaminantes Químicos del Agua/química , Cerámica/química , Bromatos/química , Purificación del Agua/métodos , Peróxido de Hidrógeno/química , Polímeros/química , Oxidación-Reducción , Nanopartículas del Metal/química
11.
Neurol Sci ; 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39269572

RESUMEN

BACKGROUD: Multiple Sclerosis (MS) is a complex and chronic autoimmune disease that affects the central nervous system. Inflammation and demyelination characterize it, which results in a range of neurological impairments. The increasing worldwide occurrence of MS, affecting an estimated 2.8 million individuals in 2020, highlights the urgent requirement for further research to tackle the significant impact it has on individuals and healthcare systems globally. OBJECTIVE: In this study, we wanted to explore the complex function of the endoplasmic reticulum (ER) in the origin, development, and resolution of MS, emphasizing its importance in neuroinflammatory illnesses. The ER has become a central focus in comprehending the pathogenesis of MS. Upon reviewing the literature, we observed a lack of thorough analysis that explores the involvement of endoplasmic reticulum stress in multiple sclerosis. Thus, we aimed through this research to examine the correlations between ER stress and its influence on immunological dysregulation, demyelination, and neurodegeneration in MS. FINDINGS: Based on the latest clinical trials, we suggested theories that explore possible biomarkers linked to ER stress and the unfolded protein response. Identifying molecules that are suggestive of early stages of illness and can serve as prognostic tools for improving our understanding of the heterogeneity of MS and offering novel approaches for managing the disease. Finally, through our comprehensive search, we wanted to offer a plan for future research, suggesting new and creative methods for managing MS and encouraging the creation of specific treatments that aim to reduce the impact of MS on individuals worldwide.

12.
Dis Esophagus ; 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39237116

RESUMEN

Proton pump inhibitors (PPIs) are one of the standards of care of eosinophilic esophagitis (EoE) treatment, though PPI response rates are variable ranging from 23 to 63% in pediatric studies. We sought to determine if expression of select genes in esophageal mucosa can predict PPI responsiveness in EoE. Children with a new diagnosis of EoE (15 or more eosinophils/hpf on esophageal biopsy) were prospectively treated with 8 weeks of PPI therapy before follow-up esophagogastroduodenoscopy (EGD). Children with <15 eosinophils/hpf on follow-up were classified as having PPI-Responsive EoE (PPI-R) and ≥ 15 eosinophils/hpf as PPI-Nonresponsive EoE (PPI-NR). Using the Nanostring nCounter Analysis System, mRNA expression of a custom panel of genes was measured in esophageal biopsies. Immunohistochemical staining of biopsies was performed. Among children with EoE, 32% (8/25) had PPI-R EoE. ATP12A, ATP4A, tryptase-beta 2 (TPSB2), CLC and IL13 had higher expression in PPI-NR EoE compared to PPI-R EoE or controls. Immunohistochemical staining of ATP12A was higher among PPI-R EoE and PPI-NR EoE, compared to non-EoE controls. In this study, PPI-NR EoE had significantly higher baseline gene expression of mast cell, cytokine, proton pump, and eosinophil genes compared to PPI-R EoE. PPIs may be involved in an inflammatory cascade of mast cell activation that stimulates IL-13 release, which upregulates ATP12A and ATP4A that leads to eosinophil recruitment. Histologic PPI failure may occur when increased gene expression of these components is high and cannot be overcome pharmacologically, especially in the case of proton pump genes.

13.
Sensors (Basel) ; 24(11)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38894122

RESUMEN

This paper presents a novel polarization-insensitive dual-band frequency-selective surface (FSS)-based electromagnetic shield. The miniaturized FSS unit cell consists of a modified Jerusalem crossed loop and a corner-modified square loop. These FSS elements are arranged in a co-planner configuration over a single-layer Rogers 5880 substrate and simultaneously offer effective shielding in the X- and Ku-bands. Moreover, the FSS manifests polarization-independent and angularly stable band-reject filter characteristics over various oblique angles of incidence for both the TE and TM polarizations with virtuous attenuation at both resonances. In addition, the FSS structure is modelled into an equivalent lumped circuit to better analyze the phenomenon of EM wave suppression. A finite prototype of FSS is fabricated and tested. The simulated and measured results are in good agreement, thus making it a potential candidate for RF shielding/isolation applications.

14.
Small ; 19(12): e2206550, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36587964

RESUMEN

Current electrical contact models are occasionally insufficient at the nanoscale owing to the wide variations in outcomes between 2D mono and multi-layered and bulk materials that result from their distinctive electrostatics and geometries. Contrarily, devices based on 2D semiconductors present a significant challenge due to the requirement for electrical contact with resistances close to the quantum limit. The next generation of low-power devices is already hindered by the lack of high-quality and low-contact-resistance contacts on 2D materials. The physics and materials science of electrical contact resistance in 2D materials-based nanoelectronics, interface configurations, charge injection mechanisms, and numerical modeling of electrical contacts, as well as the most pressing issues that need to be resolved in the field of research and development, will all be covered in this review.

15.
Mod Pathol ; 36(6): 100142, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36813116

RESUMEN

Testicular juvenile granulosa cell tumors (JGCTs) are a rare type of sex cord-stromal tumor, accounting for <5% of all neoplasms of the prepubertal testis. Previous reports have demonstrated sex chromosome anomalies in a small subset of cases, but the molecular alterations associated with JGCTs remain largely undescribed. We evaluated 18 JGCTs using massive parallel DNA and RNA sequencing panels. The median patient age was <1 month (range, newborn to 5 months). The patients presented with scrotal or intra-abdominal masses/enlargement, and all underwent radical orchiectomy (17 unilateral and 1 bilateral). The median tumor size was 1.8 cm (range, 1.3-10.5 cm). Histologically, the tumors were purely cystic/follicular or mixed (ie, solid and cystic/follicular). All cases were predominantly epithelioid, with 2 exhibiting prominent spindle cell components. Nuclear atypia was mild or absent, and the median number of mitoses was 0.4/mm2 (range, 0-10/mm2). Tumors frequently expressed SF-1 (11/12 cases, 92%), inhibin (6/7 cases, 86%), calretinin (3/4 cases, 75%), and keratins (2/4 cases, 50%). Single-nucleotide variant analysis demonstrated the absence of recurrent mutations. RNA sequencing did not detect gene fusions in 3 cases that were sequenced successfully. Recurrent monosomy 10 was identified in 8 of 14 cases (57%) with interpretable copy number variant data, and multiple whole-chromosome gains were present in the 2 cases with significant spindle cell components. This study demonstrated that testicular JGCTs harbor recurrent loss of chromosome 10 and lack the GNAS and AKT1 variants described in their ovarian counterparts.


Asunto(s)
Tumor de Células de la Granulosa , Neoplasias Ováricas , Tumores de los Cordones Sexuales y Estroma de las Gónadas , Neoplasias Testiculares , Masculino , Recién Nacido , Femenino , Humanos , Lactante , Tumor de Células de la Granulosa/genética , Cromosomas Humanos Par 10 , Neoplasias Testiculares/genética , Neoplasias Testiculares/patología , Neoplasias Ováricas/patología , Tumores de los Cordones Sexuales y Estroma de las Gónadas/genética , Tumores de los Cordones Sexuales y Estroma de las Gónadas/patología
16.
J Med Virol ; 95(1): e27893, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35644904

RESUMEN

BACKGROUND: The development of oral and oropharyngeal cancers is associated with human papillomavirus (HPV) infection. However, debate exists about the prevalence of high-risk oral HPV (HR-HPV) and its associated risk factors. This study evaluated the distribution of genotypes and associated risk factors of oral HR-HPV infection in the normal oral mucosa of the Pakistani female population with general gynecological problems. METHODS: A total of 200 females from a regional gynecological hospital in Pakistan were included in this cross-sectional study. A self-administered questionnaire was carried out, followed by the study participants' oral and dental examinations. Whole saliva was collected by a drooling method. The viral DNA extraction and oral HR-HPV genotyping were detected via real-time polymerase chain reaction. RESULTS: Among the 200 females (mean age, 37.76 years), 22 females (11%) were positive for oral HR-HPV DNA. Single oral HR-HPV infection was seen in 8%, whereas co-infection was observed in 3% with HPV16 and HPV18 most common genotypes. Comparison of the risk factors like oral sex history odds ratio (OR 8.21, 95% confidence interval [CI] 1.85-28.16; p < 0.005), and open-mouth kissing (OR, 5.17; 95% CI 1.48-27.41; p = 0.005) with oral HR-HPV infection was found to be significantly associated. CONCLUSION: In Pakistan, oral HR-HPV-positive infection is not uncommon; HPV16 and HPV18 are the most frequent genotypes. Furthermore, this study also provides data that oral HR-HPV positive infection was significantly associated with sexual behaviors. Therefore, preventive health efforts, like health education and vaccination, should be practiced.


Asunto(s)
Infecciones por Papillomavirus , Humanos , Femenino , Adulto , Infecciones por Papillomavirus/complicaciones , Pakistán/epidemiología , Virus del Papiloma Humano , Estudios Transversales , Factores de Riesgo , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Prevalencia , Papillomaviridae/genética
17.
Histopathology ; 82(2): 296-304, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36208048

RESUMEN

Low-grade oncocytic tumour (LOT) of the kidney has recently emerged as a potential novel tumour type. Despite similarity to oncocytoma or eosinophilic chromophobe renal cell carcinoma, it shows diffuse keratin 7 immunohistochemistry (IHC) and negative KIT (CD117), which differs from both. We aimed to identify the molecular characteristics of these tumours. Seventeen tumours (one male, 16 female, nine previously published) fitting the original description of this entity (solid eosinophilic cell morphology, often with areas of tumour cells loosely stretched in oedematous stroma, and the above IHC features) were analysed with a next-generation sequencing panel of 324 cancer-associated genes from formalin-fixed, paraffin-embedded tissue. All tumours harboured at least one alteration in either TSC1 (n = 7, 41%), TSC2 (n = 2, 12%), MTOR (n = 5, 29%) or PIK3CA (n = 4, 24%). Four tumours harboured a second alteration, including two NF2, one each in conjunction with MTOR and TSC2 alterations, one PTEN with TSC1 alteration and one tumour with both MTOR and TSC1 alterations. No other renal cancer-related or recurring gene alterations were identified. In addition to the previously described IHC findings, 16 of 16 were positive for GATA3. Eleven patients with follow-up had no metastases or recurrent tumours. Recurrent tuberous sclerosis/MTOR pathway gene alterations in LOT support its consideration as a distinct morphological, immunohistochemical and genetic entity. PIK3CA is another pathway member that may be altered in these tumours. Further study will be necessary to determine whether tumour behaviour or syndromic associations differ from those of oncocytoma and chromophobe carcinoma, warranting different clinical consideration.


Asunto(s)
Adenoma Oxifílico , Carcinoma de Células Renales , Neoplasias Renales , Humanos , Masculino , Femenino , Recurrencia Local de Neoplasia , Carcinoma de Células Renales/genética , Neoplasias Renales/genética , Mutación , Adenoma Oxifílico/genética , Riñón , Serina-Treonina Quinasas TOR/genética , Factor de Transcripción GATA3/genética , Fosfatidilinositol 3-Quinasa Clase I/genética
18.
Histopathology ; 82(7): 1079-1088, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36929593

RESUMEN

Large cell calcifying Sertoli cell tumour (LCCSCT) is a type of testicular sex cord-stromal tumour that may occur sporadically or in the context of Carney complex and other genetic syndromes. A subset is clinically malignant, and the molecular mechanisms that drive such aggressive behaviour remain unknown. METHODS AND RESULTS: We analysed 21 samples from 20 patients with LCCSCT (12 non-metastasising and eight metastasising) using PRKAR1A immunohistochemistry (IHC) and next-generation sequencing. All tumours except two (cases 17 and 20, both metastasising) demonstrated loss of PRKAR1A expression. Among 11 cases with interpretable sequencing results, all harboured pathogenic single nucleotide variants of PRKAR1A. Evidence of loss of heterozygosity (LOH) of PRKAR1A was present in all tumours with interpretable zygosity data, but the mechanisms of LOH were different for non-metastasising and metastasising tumours. Non-metastasising tumours demonstrated only copy-neutral LOH, while metastasising tumours demonstrated a spectrum of mechanisms of LOH, including copy-loss LOH, two concurrent mutations or copy-neutral LOH. Relevant molecular findings in non-metastasising LCCSCT were limited to PRKAR1A variants. In contrast, all metastasising LCCSCTs with interpretable data harboured additional pathogenic variants, including (but not restricted to) BRCA2 mutations with evidence of LOH and bi-allelic CDKN2A/B deletions. Three patients harboured PRKAR1A variants of inferred germline origin, including one with Carney complex and two without known syndromic features. CONCLUSIONS: This study further confirms that PRKAR1A IHC is a useful diagnostic tool for both non-metastasising and metastasising tumours and suggests that molecular analyses can be helpful to identify non-metastasising tumours with malignant potential in selected patients. Importantly, these results highlight that germline assessment could be beneficial for all patients presenting with LCCSCT.


Asunto(s)
Complejo de Carney , Tumor de Células de Sertoli , Tumores de los Cordones Sexuales y Estroma de las Gónadas , Neoplasias Testiculares , Masculino , Humanos , Tumor de Células de Sertoli/genética , Tumor de Células de Sertoli/química , Neoplasias Testiculares/metabolismo , Tumores de los Cordones Sexuales y Estroma de las Gónadas/patología , Mutación
19.
BMC Infect Dis ; 23(1): 872, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38087193

RESUMEN

BACKGROUND: The corona virus SARS-CoV-2 is the causative agent of recent most global pandemic. Its genome encodes various proteins categorized as non-structural, accessory, and structural proteins. The non-structural proteins, NSP1-16, are located within the ORF1ab. The NSP3, 4, and 6 together are involved in formation of double membrane vesicle (DMV) in host Golgi apparatus. These vesicles provide anchorage to viral replicative complexes, thus assist replication inside the host cell. While the accessory genes coded by ORFs 3a, 3b, 6, 7a, 7b, 8a, 8b, 9b, 9c, and 10 contribute in cell entry, immunoevasion, and pathological progression. METHODS: This in silico study is focused on designing sequence specific siRNA molecules as a tool for silencing the non-structural and accessory genes of the virus. The gene sequences of NSP3, 4, and 6 along with ORF3a, 6, 7a, 8, and 10 were retrieved for conservation, phylogenetic, and sequence logo analyses. siRNA candidates were predicted using siDirect 2.0 targeting these genes. The GC content, melting temperatures, and various validation scores were calculated. Secondary structures of the guide strands and siRNA-target duplexes were predicted. Finally, tertiary structures were predicted and subjected to structural validations. RESULTS: This study revealed that NSP3, 4, and 6 and accessory genes ORF3a, 6, 7a, 8, and 10 have high levels of conservation across globally circulating SARS-CoV-2 strains. A total of 71 siRNA molecules were predicted against the selected genes. Following rigorous screening including binary validations and minimum free energies, final siRNAs with high therapeutic potential were identified, including 7, 2, and 1 against NSP3, NSP4, and NSP6, as well as 3, 1, 2, and 1 targeting ORF3a, ORF7a, ORF8, and ORF10, respectively. CONCLUSION: Our novel in silico pipeline integrates effective methods from previous studies to predict and validate siRNA molecules, having the potential to inhibit viral replication pathway in vitro. In total, this study identified 17 highly specific siRNA molecules targeting NSP3, 4, and 6 and accessory genes ORF3a, 7a, 8, and 10 of SARS-CoV-2, which might be used as an additional antiviral treatment option especially in the cases of life-threatening urgencies.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , ARN Interferente Pequeño/genética , Filogenia , Perfilación de la Expresión Génica
20.
J Fluoresc ; 33(1): 261-265, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36401734

RESUMEN

A group of selected phenols i.e., picric acid, p-Nitrophenol, m-Nitrophenol, o-Nitrophenol, and phenol interactions were studied with a fluorescent probe carbazole in a micellar system of CTAB. CTAB concentration was optimized for maximum quenching of carbazole for each studied phenol. Interaction was studied in 0.02 and 0.1 mol/dm3 CTAB. All the studied phenols resulted in the quenching of carbazole in both CTAB concentrations though lower CTAB concentration was found optimum for highest quenching of the probe carbazole. Carbazole fluorescence quenching with phenols were explained with the help of Stern-Volmer equation that produced the constants of Stern-Volmer ([Formula: see text]). [Formula: see text] shows the sensitiveness of the method for the studied phenol and were observed in the order picric acid > phenol > m-Nitrophenol > p-Nitrophenol > o-Nitrophenol. Detection threshold (DT) and quantification threshold (QT) were observed in the order 1.76 [Formula: see text] 10-7 - 6.30 [Formula: see text] 10-7 mol/dm3 and 5.898 [Formula: see text] 10-7 - 2.11 [Formula: see text] 10-6 mol/dm3 respectively. The method is reproducible and is effective for the determination of studied phenols in the samples.

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