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1.
Quant Imaging Med Surg ; 14(5): 3366-3380, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38720835

RESUMEN

Background: The threshold value of consolidation-to-tumor ratio (CTR) for distinguishing between ground-glass opacity (GGO)-predominant and solid-predominant ground-glass nodules (GGNs) needs to be clarified, as the lack of clarity has caused the prognostic implications to remain ambiguous. This study aimed to determine the threshold value of CTR for distinguishing between GGO-predominant GGNs and solid-predominant GGNs and elucidate the prognostic implications of the solid-predominant GGNs categorized by CTR on c-stage IA lung adenocarcinoma. Methods: Between January 2016 and October 2018, 764 c-stage IA lung adenocarcinoma cases were assembled from the First Affiliated Hospital of Chongqing Medical University. Of the 764 lesions, 515 (67.4%) were nodules with a GGO component, and 249 (32.6%) were solid nodules (SNs) on thin-section computed tomography (CT). We evaluated the correlation of the 3-dimensional (3D) consolidation component volume ratio with CTR based on the coefficient of determination, r. After receiver operating characteristic (ROC) analysis of 515 GGNs, we defined the nodule with CTR >0.750 as solid-predominant GGN and the nodule with CTR ≤0.750 as GGO-predominant GGN. Subsequently, the prognosis of 439 patients who had follow-up registration was evaluated. Survival curves were calculated using the Kaplan-Meier method, and the log-rank test was employed to compare survival rates among different groups. Cox proportional hazard regression models were applied to evaluate the independent risk factors for recurrence-free survival (RFS). Results: Among 764 patients, 515 (67.4%) were nodules with a GGO component, and 249 (32.6%) were SNs on thin-section CT. For 515 GGNs, the 3D consolidation component volume ratio correlated well with CTR (r=0.888). CTR tended to be slightly larger than the 3D consolidation component volume ratio. A 3D consolidation component volume ratio >50% was best predicted by CTR >0.750, followed by CTR >0.549. CTR >0.750 and CTR >0.549 predicted 3D consolidation component volume ratio >50% with 85% and 99.2% sensitivity and 91.6% and 57.2% specificity, respectively. The 5-year RFS and overall survival (OS) of patients with 0.750< CTR <1 were worse than those of patients with 0≤ CTR ≤0.750 (P<0.001 and P<0.001, respectively) but better than those of patients with CTR =1 (P=0.002 and P=0.03, respectively). Carcinoembryonic antigen (CEA) >2.1 [hazard ratio (HR) =12.516, 95% confidence interval (CI): 1.729-90.598], CTR >0.750 (HR =13.934, 95% CI: 3.341-58.123), larger consolidation component size with diameter more than 20 mm (HR =1.855, 95% CI: 1.242-2.770), poorly differentiated (HR =1.622, 95% CI: 1.056-2.491), lymph node metastasis (HR =2.473, 95% CI: 1.601-3.821), and sublobar resection (HR =2.596, 95% CI: 1.701-3.962) could predict the poor prognosis. Patients with 0≤ CTR ≤0.750 receiving sublobar resection had prognoses comparable to those receiving lobar resection, whether the tumor size ≤2 cm or consolidation component size ≤3 cm. Lobar resection was superior to sublobar resection for non-small cell lung cancer (NSCLC) ≤2 cm with CTR >0.750. Conclusions: Compared to CTR =0.5, the 2-dimensional (2D) CTR =0.750 found using the 3D consolidation component volume ratio as the gold standard better differentiated between solid-predominant GGNs and GGO-predominant GGNs. CTR >0.750 was an independent risk factor associated with the poor prognosis of patients with c-stage IA lung adenocarcinoma. Sublobar resection should be cautiously adopted in GGNs with 0.750< CTR ≤1.

2.
Int J Biol Macromol ; 260(Pt 2): 129331, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38218299

RESUMEN

Tuberculosis (TB), a leading cause of mortality globally, is a chronic infectious disease caused by Mycobacterium tuberculosis that primarily infiltrates the lung. The mature crRNAs in M. tuberculosis transcribed from the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) locus exhibit an atypical structure featured with 5' and 3' repeat tags at both ends of the intact crRNA, in contrast to typical Type-III-A crRNAs that possess 5' repeat tags and partial crRNA sequences. However, this structural peculiarity particularly concerning the specific binding characteristics of the 3' repeat end within the mature crRNA within the Csm complex, has not been comprehensively elucidated. Here, our Mycobacteria CRISPR-Csm complexes structure represents the largest Csm complex reported to date. It incorporates an atypical Type-III-A CRISPR RNA (crRNA) (46 nt) with 5' 8-nt and 3' 4-nt repeat sequences in the stoichiometry of Mycobacteria Csm1125364151. The PAM-independent single-stranded RNAs (ssRNAs) are the most suitable substrate for the Csm complex. The 3'-repeat end trimming of mature crRNA was not necessary for its cleavage activity in Type-III-A Csm complex. Our work broadens our understanding of the Type-III-A Csm complex and identifies another mature crRNA processing mechanism in the Type-III-A CRISPR-Cas system based on structural biology.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Humanos , ARN Guía de Sistemas CRISPR-Cas , ARN Bacteriano/genética , Sistemas CRISPR-Cas/genética , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Tuberculosis/genética
3.
Cancer Imaging ; 24(1): 15, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38254185

RESUMEN

BACKGROUND: To compare the diagnostic performance of Lung-RADS (lung imaging-reporting and data system) 2022 and PNI-GARS (pulmonary node imaging-grading and reporting system). METHODS: Pulmonary nodules (PNs) were selected at four centers, namely, CQ Center (January 1, 2018-December 31, 2021), HB Center (January 1, 2021-June 30, 2022), SC Center (September 1, 2021-December 31, 2021), and SX Center (January 1, 2021-December 31, 2021). PNs were divided into solid nodules (SNs), partial solid nodules (PSNs) and ground-glass nodules (GGNs), and they were then classified by the Lung-RADS and PNI-GARS. The sensitivity, specificity and agreement rate were compared between the two systems by the χ2 test. RESULTS: For SN and PSN, the sensitivity of PNI-GARS and Lung-RADS was close (SN 99.8% vs. 99.4%, P < 0.001; PSN 99.9% vs. 98.4%, P = 0.015), but the specificity (SN 51.2% > 35.1%, PSN 13.3% > 5.7%, all P < 0.001) and agreement rate (SN 81.1% > 74.5%, P < 0.001, PSN 94.6% > 92.7%, all P < 0.05) of PNI-GARS were superior to those of Lung-RADS. For GGN, the sensitivity (96.5%) and agreement rate (88.6%) of PNI-GARS were better than those of Lung-RADS (0, 18.5%, P < 0.001). For the whole sample, the sensitivity (98.5%) and agreement rate (87.0%) of PNI-GARS were better than Lung-RADS (57.5%, 56.5%, all P < 0.001), whereas the specificity was slightly lower (49.8% < 53.4%, P = 0.003). CONCLUSION: PNI-GARS was superior to Lung-RADS in diagnostic performance, especially for GGN.


Asunto(s)
Neoplasias Pulmonares , Nódulos Pulmonares Múltiples , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Nódulos Pulmonares Múltiples/diagnóstico por imagen , China
4.
ACS Chem Biol ; 19(1): 15-21, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38193366

RESUMEN

The active removal of DNA methylation marks is governed by the ten-eleven translocation (TET) family of enzymes (TET1-3), which iteratively oxidize 5-methycytosine (5mC) into 5-hydroxymethycytosine (5hmC), and then 5-formylcytosine (5fC) and 5-carboxylcytosine (5caC). TET proteins are frequently mutated in myeloid malignancies or inactivated in solid tumors. These methylcytosine dioxygenases are α-ketoglutarate (αKG)-dependent and are, therefore, sensitive to metabolic homeostasis. For example, TET2 is activated by vitamin C (VC) and inhibited by specific oncometabolites. However, understanding the regulation of the TET2 enzyme by different metabolites and its activity remains challenging because of limitations in the methods used to simultaneously monitor TET2 substrates, products, and cofactors during catalysis. Here, we measure TET2-dependent activity in real time using NMR. Additionally, we demonstrate that in vitro activity of TET2 is highly dependent on the presence of VC in our system and is potently inhibited by an intermediate metabolite of the TCA cycle, oxaloacetate (OAA). Despite these opposing effects on TET2 activity, the binding sites of VC and OAA on TET2 are shared with αKG. Overall, our work suggests that NMR can be effectively used to monitor TET2 catalysis and illustrates how TET activity is regulated by metabolic and cellular conditions at each oxidation step.


Asunto(s)
5-Metilcitosina , Dioxigenasas , 5-Metilcitosina/metabolismo , Proteínas de Unión al ADN/metabolismo , Citosina , Oxidación-Reducción , Metilación de ADN , Dioxigenasas/metabolismo
5.
Cancer Imaging ; 23(1): 115, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38041175

RESUMEN

BACKGROUND: We aim to compare the differences in growth characteristics between part-solid and solid lung adenocarcinoma, and to investigate the value of volume doubling time (VDT) or mass doubling time (MDT) in predicting lymph node (LN) metastasis and preoperative evaluation in patients of early-stage (IA) non-small cell lung cancer (NSCLC). METHOD: We reviewed 8,653 cases of surgically resected stage IA lung adenocarcinoma between 2018 and 2022, with two follow-up visits at least 3 months apart, comparing diameter, volume, and mass growth of pSN and SN. VDT and MDT calculations for nodules with a volume change of at least 25%. Univariable or multivariable analysis was used to identify the risk factors. The area under the curve (AUC) for the receiver operating characteristic (ROC) curves was used to evaluate the diagnostic value. RESULTS: A total of 144 patients were included 114 with solid nodules (SN) and 25 with part-solid nodules (pSN). During the follow-up period, the mean VDTt and MDTt of SN were shorter than those of pSN, 337 vs. 541 days (p = 0.005), 298 vs. 458 days (p = 0.018), respectively. Without considering the ground-glass component, the mean VDTc and MDTc of SN were shorter than the solid component of pSN, 337 vs. 498 days (p = 0.004) and 298 vs. 453 days (p = 0.003), respectively. 27 nodules were clinically and pathologically diagnosed as N1/N2. Logistic regression identified initial diameter (p < 0.001), consolidation increase (p = 0.019), volume increase (p = 0.020), mass increase (p = 0.021), VDTt (p = 0.002), and MDTt (p = 0.004) were independent factors for LN metastasis. The ROC curves showed that the AUC for VDTt was 0.860 (95% CI, 0.778-0.943; p < 0.001) and for MDTt was 0.848 (95% CI, 0.759-0.936; p < 0.001). CONCLUSIONS: Our study showed significant differences in the growth characteristics of pSN and SN, and the application of VDT and MDT could be a valid predictor LN metastasis in patients with early-stage NSCLC.


Asunto(s)
Adenocarcinoma del Pulmón , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Adenocarcinoma del Pulmón/patología , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/patología , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Metástasis Linfática , Estadificación de Neoplasias , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos
6.
PLoS Genet ; 19(9): e1010930, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37729124

RESUMEN

Cas12g is an endonuclease belonging to the type V RNA-guided CRISPR-Cas family. It is known for its ability to cleave RNA substrates using a conserved endonuclease active site located in the RuvC domain. In this study, we determined the crystal structure of apo-Cas12g, the cryo-EM structure of the Cas12g-sgRNA binary complex and investigated conformational changes that occur during the transition from the apo state to the Cas12g-sgRNA binary complex. The conserved zinc finger motifs in Cas12g undergo an ordered-to-disordered transition from the apo to the sgRNA-bound state and their mutations negatively impact on target RNA cleavage. Moreover, we identified a lid motif in the RuvC domain that undergoes transformation from a helix to loop to regulate the access to the RuvC active site and subsequent cleavage of the RNA substrate. Overall, our study provides valuable insights into the mechanisms by which Cas12g recognizes sgRNA and the conformational changes it undergoes from sgRNA binding to the activation of the RNase active site, thereby laying a foundation for the potential repurposing of Cas12g as a tool for RNA-editing.


Asunto(s)
Endonucleasas , ARN Guía de Sistemas CRISPR-Cas , División del ARN , Endonucleasas/genética , Endorribonucleasas , ARN/genética
7.
J Eur Acad Dermatol Venereol ; 37(12): 2583-2588, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37591629

RESUMEN

BACKGROUND: Wide local excision (WLE) of the nail unit is widely used in treating in situ and minimally invasive malignant subungual tumours. After WLE, diverse reconstruction methods have been reported. However, the best repair method has yet to be determined. OBJECTIVE: To compare the repair effects and postoperative morbidity of secondary intention healing (SIH), artificial dermis grafting combined with secondary intention healing (ADGSIH) and full-thickness skin grafting (FSG) after WLE of the nail unit. METHODS: We retrospectively reviewed 21 patients who underwent WLE of the nail unit. The re-epithelializing time, functional and cosmetic outcomes, postoperative complications and patients' satisfaction were assessed from the follow-up records. RESULTS: The FSG group showed more rapid healing and better functional and cosmetic outcomes than the SIH and ADGSIH groups. The ADGSIH and FSG groups showed significant pain relief compared to the SIH group. No serious early and late postoperative complications were reported. The median follow-up period was 26 months, and no recurrence was observed. All patients were satisfied with the treatment. CONCLUSIONS: FSG after the WLE of the nail unit is a therapeutic option with convenient application, significant pain relief, rapid recovery and satisfying functional and cosmetic outcomes.


Asunto(s)
Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/cirugía , Neoplasias Cutáneas/patología , Estudios Retrospectivos , Uñas/cirugía , Uñas/patología , Complicaciones Posoperatorias/epidemiología , Dolor
8.
Diagnostics (Basel) ; 13(13)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37443604

RESUMEN

BACKGROUND: In addition to the diameters of pulmonary nodules, the number and morphology of blood vessels in pure ground-glass nodules (pGGNs) were closely related to the occurrence of lung cancer. Moreover, the benign and malignant signs of nodules were also valuable for the identification of nodules. Based on these two points, we tried to revise Lung-RADS 2022 and proposed our Modified Lung-RADS. The aim of the study was to verify the diagnostic performance of Modified Lung-RADS for pulmonary solid nodules (SNs) and pure ground-glass nodules (pGGNs) in patients with previous malignancies. METHODS: The chest CT and clinical data of patients with prior cancer who underwent pulmonary nodulectomies from 1 January 2018 to 30 November 2021 were enrolled according to inclusion and exclusion criteria. A total of 240 patients with 293 pulmonary nodules were included in this study. In contrast with the original version, the risk classification of pGGNs based on the GGN-vascular relationships (GVRs), and the SNs without burrs and with benign signs, could be downgraded to category 2. The sensitivity, specificity, and agreement rate of the original Lung-RADS 2022 and Modified Lung-RADS for pGGNs and SNs were calculated and compared. RESULTS: Compared with the original version, the sensitivity and agreement rate of the Modified version for pGGNs increased from 0 and 23.33% to 97.10% and 92.22%, respectively, while the specificity decreased from 100% to 76.19%. As regards SNs, the specificity and agreement rate of the Modified version increased from 44.44% to 75.00% (p < 0.05) and 88.67% to 94.09% (p = 0.052), respectively, while the sensitivity was unchanged (98.20%). CONCLUSIONS: In general, the diagnostic efficiency of Modified Lung-RADS was superior to that of the original version, and Modified Lung-RADS could be a preliminary attempt to improve Lung-RADS 2022.

9.
Front Oncol ; 13: 1141820, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37188196

RESUMEN

Objective: To investigate the diagnostic value of dermoscopy in defining the tumor margin of cutaneous squamous cell carcinoma (cSCC) for the appropriate surgical margin. Methods: A total of 90 cSCC patients were enrolled in the study. All patients were recruited into two groups: those who preserved intact macroscopic features of neoplasms without or after incisional biopsy and those with uncertain residual tumors after excisional biopsy. A dermoscopy-defined surgical margin of 8mm outward was used according to the tumor boundaries observed with the naked eye and dermoscopy. All excised tumor specimens were divided into serial sections according to the four "3, 6, 9, 12" directions at every 4-mm interval from the dermoscopy-detected tumor margin. Pathological examination was performed at 0 mm, 4 mm, and 8 mm margins to confirm tumor remnants. Results: Retrospective analysis of dermatoscopic results showed inconsistent clinical and dermatoscopic borders in 43 of 90 cases (47.8%). The ability of dermoscopy to detect tumor borders showed no statistical difference between the two groups (p > 0.05). In the unbiopsy or incisional biopsy group, 66.6% of the tumors were resected with a 4-mm margin and 98.3% with an 8-mm margin, with significant differences (p = 0.047). For patients with inconspicuous clinical evidence of residual tumor after excisional biopsy, the tumor clearance rate was 53.3% at 0 mm, 93.3% at 4 mm, and 100.0% at 8 mm. Statistically significant differences were noted between 0 mm and 4 mm (p = 0.017), as well as between 0 mm and 8 mm (p = 0.043) but did not differ between 4 mm and 8 mm (p > 0.05). Conclusions: Dermoscopy defined the tumor margin of cSCC better than visual inspection alone. Direct dermoscopic-guided surgery with at least 8-mm expansion was recommended for high-risk cSCC. Dermoscopy also assisted in identifying surgical margins at the healing biopsy site, making 8 mm still the recommended expansion range.

10.
Quant Imaging Med Surg ; 13(5): 2871-2880, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37179919

RESUMEN

Background: For lung cancer screening in patients with previous malignant tumors, Lung Imaging Reporting and Data System (Lung-RADS) and other lung cancer screening tools are controversial in terms of requirements for the previous cancer history. This study investigated the effect of the length and type of malignancy history on the diagnostic efficacy of Lung Imaging Reporting and Data System (Lung-RADS) 2022 in pulmonary nodules (PNs). Methods: Chest computed tomography and clinical data of PNs in patients with a history of cancer who underwent surgical resection in The First Affiliated Hospital of Chongqing Medical University from January 1, 2018, to November 30, 2021, were retrospectively collected and evaluated based on Lung-RADS. All PNs were divided into 2 groups: the prior lung cancer (PLC) and the prior extrapulmonary cancer (PEPC) groups. Each group was divided into the ≥5 years and <5 years groups based on the duration of cancer history. The diagnostic agreement of Lung-RADS was evaluated based on the pathological diagnosis of nodules after operation. The diagnostic agreement rate (AR) of Lung-RADS and the composition ratios of different types between different groups were calculated and compared. Results: A total of 451 patients with 565 PNs were included in this study. These patients were divided into the PLC group (<5 years: 135 cases, 175 PNs; ≥5 years: 9 cases, 12 PNs) and the PEPC group (<5 years: 219 cases, 278 PNs; ≥5 years: 88 cases, 100 PNs). The diagnostic AR of partial solid nodules (93.0%; 95% CI: 88.7-97.2%) and solid nodules (88.1%; 95% CI: 84.1-92.1%) was close (P=0.13), while both were higher than that of the pure ground-glass nodules (24.0%; 95% CI: 17.5-30.4%; all P values <0.001). Within 5 years, the composition ratio of PNs and the diagnostic AR (PLC: 58.9%, 95% CI: 51.5-66.2%; PEPC: 76.6%, 95% CI: 71.6-81.6%) between the PLC and PEPC groups were all different (all P values <0.001), and the others [composition ratio of PNs & the diagnostic AR: PLC (≥5 years) vs. PEPC (≥5 years); PLC (<5 years) vs. PLC (≥5 years); PEPC (<5 years) vs. PEPC (≥5 years)] were similar (all P values >0.05; range: 0.10-0.93). Conclusions: The length of prior cancer history may affect the diagnostic agreement of Lung-RADS, especially for patients with prior lung cancer within 5 years.

11.
Nat Commun ; 14(1): 2223, 2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37076513

RESUMEN

The chiral charge density wave is a many-body collective phenomenon in condensed matter that may play a role in unconventional superconductivity and topological physics. Two-dimensional chiral charge density waves provide the building blocks for the fabrication of various stacking structures and chiral homostructures, in which physical properties such as chiral currents and the anomalous Hall effect may emerge. Here, we demonstrate the phase manipulation of two-dimensional chiral charge density waves and the design of in-plane chiral homostructures in 1T-TaS2. We use chiral Raman spectroscopy to directly monitor the chirality switching of the charge density wave-revealing a temperature-mediated reversible chirality switching. We find that interlayer stacking favours homochirality configurations, which is confirmed by first-principles calculations. By exploiting the interlayer chirality-locking effect, we realise in-plane chiral homostructures in 1T-TaS2. Our results provide a versatile way to manipulate chiral collective phases by interlayer coupling in layered van der Waals semiconductors.

12.
J Virol ; 97(4): e0182922, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-36943056

RESUMEN

Spring viremia of carp virus (SVCV) is a highly pathogenic Vesiculovirus infecting the common carp, yet neither a vaccine nor effective therapies are available to treat spring viremia of carp (SVC). Like all negative-sense viruses, SVCV contains an RNA genome that is encapsidated by the nucleoprotein (N) in the form of a ribonucleoprotein (RNP) complex, which serves as the template for viral replication and transcription. Here, the three-dimensional (3D) structure of SVCV RNP was resolved through cryo-electron microscopy (cryo-EM) at a resolution of 3.7 Å. RNP assembly was stabilized by N and C loops; RNA was wrapped in the groove between the N and C lobes with 9 nt nucleotide per protomer. Combined with mutational analysis, our results elucidated the mechanism of RNP formation. The RNA binding groove of SVCV N was used as a target for drug virtual screening, and it was found suramin had a good antiviral effect. This study provided insights into RNP assembly, and anti-SVCV drug screening was performed on the basis of this structure, providing a theoretical basis and efficient drug screening method for the prevention and treatment of SVC. IMPORTANCE Aquaculture accounts for about 70% of global aquatic products, and viral diseases severely harm the development of aquaculture industry. Spring viremia of carp virus (SVCV) is the pathogen causing highly contagious spring viremia of carp (SVC) disease in cyprinids, especially common carp (Cyprinus carpio), yet neither a vaccine nor effective therapies are available to treat this disease. In this study, we have elucidated the mechanism of SVCV ribonucleoprotein complex (RNP) formation by resolving the 3D structure of SVCV RNP and screened antiviral drugs based on the structure. It is found that suramin could competitively bind to the RNA binding groove and has good antiviral effects both in vivo and in vitro. Our study provides a template for rational drug discovery efforts to treat and prevent SVCV infections.


Asunto(s)
Modelos Moleculares , Rhabdoviridae , Ribonucleoproteínas , Proteínas Virales , Ribonucleoproteínas/química , Ribonucleoproteínas/metabolismo , Rhabdoviridae/química , Rhabdoviridae/efectos de los fármacos , Proteínas Virales/química , Proteínas Virales/metabolismo , Estructura Cuaternaria de Proteína , Antivirales/farmacología , Evaluación Preclínica de Medicamentos , Microscopía por Crioelectrón , Suramina/farmacología
13.
Biosensors (Basel) ; 13(2)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36832047

RESUMEN

Electrical impedance spectroscopy (EIS) is widely recognized as a powerful tool in biomedical research. For example, it allows detection and monitoring of diseases, measuring of cell density in bioreactors, and characterizing the permeability of tight junctions in barrier-forming tissue models. However, with single-channel measurement systems, only integral information is obtained without spatial resolution. Here we present a low-cost multichannel impedance measurement set-up capable of mapping cell distributions in a fluidic environment by using a microelectrode array (MEA) realized in 4-level printed circuit board (PCB) technology including layers for shielding, interconnections, and microelectrodes. The array of 8 × 8 gold microelectrode pairs was connected to home-built electric circuitry consisting of commercial components such as programmable multiplexers and an analog front-end module which allows the acquisition and processing of electrical impedances. For a proof-of-concept, the MEA was wetted in a 3D printed reservoir into which yeast cells were locally injected. Impedance maps were recorded at 200 kHz which correlate well with the optical images showing the yeast cell distribution in the reservoir. Blurring from parasitic currents slightly disturbing the impedance maps could be eliminated by deconvolution using an experimentally determined point spread function. The MEA of the impedance camera can in future be further miniaturized and integrated into cell cultivation and perfusion systems such as organ on chip devices to augment or even replace light microscopic monitoring of cell monolayer confluence and integrity during the cultivation in incubation chambers.


Asunto(s)
Microscopía , Saccharomyces cerevisiae , Impedancia Eléctrica , Oro/química , Microelectrodos
14.
J Anal Toxicol ; 47(4): 346-352, 2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-36611270

RESUMEN

In forensic toxicology, hair has become a hot biological material for drug testing due to its wider detection window and noninvasive sampling process compared to traditional liquid biological materials (e.g., blood and urine). However, hair as a matrix differs from body fluids, as it is not as easily aliquoted for analysis. Nevertheless, pretreatment methods for hair detection have gradually improved from the first chemical methods, such as alkali digestion and acid hydrolysis, to now include the physical method of pulverization and further improvements beyond "pulverization" protocols. In a previous study, we updated and developed a "micropulverized extraction" method. In the present study, our aim was to gain a more complete understanding of the "micropulverized extraction" method by comparing pulverization temperature and hair particle size, as these two factors are known to influence the effectiveness of sample processing. The analytes we selected were those commonly encountered in traditional drug abuse cases: (±)-methamphetamine, (±)-amphetamine, morphine, 6-acetylmorphine, cocaine, benzoylecgonine, (--)-∆9-tetrahydrocannabinol, ketamine, (±)-norketamine and (±)-3,4-methylenedioxymethamphetamine. The analysis method was liquid chromatography-tandem mass spectrometry.


Asunto(s)
Drogas Ilícitas , Metanfetamina , N-Metil-3,4-metilenodioxianfetamina , Drogas Ilícitas/análisis , Anfetamina/análisis , Metanfetamina/análisis , N-Metil-3,4-metilenodioxianfetamina/análisis , Detección de Abuso de Sustancias/métodos , Cabello/química
15.
Front Med (Lausanne) ; 9: 1059624, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36482914

RESUMEN

Background: Onychopapilloma is generally recognized as a benign tumor of the nail bed and distal matrix. However, the origin of onychopapilloma has not been explained yet. Objective: To clarify the origin of onychopapilloma, we detected the expression patterns of hair-related keratins and epithelial keratins, which are expressed specifically in the nail unit. Materials and methods: The clinical and histopathologic features of 11 patients with onychopapilloma were analyzed, and the expression patterns of hair-related and epithelial keratins were detected. Results: Histologically, all subjects showed acanthosis, papillomatosis and matrix metaplasia within the nail bed. Immunohistochemically, the expression pattern of keratins in our standard nail unit was consistent with previous reports. "Nail matrix-related keratins" HK31, HK34, HK85, and HK86 were only expressed in the nail matrix, and "Nail bed-related keratins" HK75 and K6/K16 were only expressed in the nail bed. However, in onychopapilloma, whether adjacent to the matrix or in the distal nail bed, all cases were positive for nail bed-related keratins and HK31 but negative for other nail matrix-related keratins. Conclusion: Our study suggests that onychopapilloma may originate from the nail bed rather than the nail matrix. Furthermore, the expression of nail bed-related keratins and HK31 could be used as diagnostic markers of onychopapilloma.

16.
STAR Protoc ; 3(4): 101796, 2022 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-36353364

RESUMEN

Sr35, a coiled-coil nucleotide-binding leucine-rich repeat receptor (CC-NLR) from the wheat species Triticum monococcum can directly recognize the pathogen avirulence factor AvrSr35 and confers immunity against wheat stem rust caused by Puccinia graminis f.sp. tritici race Ug99. Assembly of a stable Sr35 resistosome induced by AvrSr35 in vitro is usually limited by protein expression and low assembly efficiency. Here, we describe the expression and purification of AvrSr35 and Sr35, in vitro assembly of Sr35 resistosome for structure determination by cryo-EM. For complete details on the use and execution of this protocol, please refer to Zhao et al. (2022).


Asunto(s)
Basidiomycota , Resistencia a la Enfermedad , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/genética , Genes de Plantas , Microscopía por Crioelectrón , Basidiomycota/genética
17.
Int J Mol Sci ; 23(19)2022 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-36232605

RESUMEN

Finding reliable miRNA markers and revealing their potential mechanisms will play an important role in the diagnosis and treatment of NSCLC. Most existing computational methods for identifying miRNA biomarkers only consider the expression variation of miRNAs or rely heavily on training sets. These deficiencies lead to high false-positive rates. The independent regulatory model is an important complement to traditional models of co-regulation and is more impervious to the dataset. In addition, previous studies of miRNA mechanisms in the development of non-small cell lung cancer (NSCLC) have mostly focused on the post-transcriptional level and did not distinguish between NSCLC subtypes. For the above problems, we improved mainly in two areas: miRNA identification based on both the NOG network and biological functions of miRNA target genes; and the construction of a 4-node directed competitive regulatory network to illustrate the mechanisms. NSCLC was classified as lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) in this work. One miRNA biomarker of LUAD (miR-708-5p) and four of LUSC (miR-183-5p, miR-140-5p, miR-766-5p, and miR-766-3p) were obtained. They were validated using literature and external datasets. The ceRNA-hub-FFL involving transcription factors (TFs), microRNAs (miRNAs), mRNAs, and long non-coding RNAs (lncRNAs) was constructed. There were multiple interactions among these components within the net at the transcriptional, post-transcriptional, and protein levels. New regulations were revealed by the network. Meanwhile, the network revealed the reasons for the previous conflicting conclusions on the roles of CD44, ACTB, and ITGB1 in NSCLC, and demonstrated the necessity of typing studies on NSCLC. The novel miRNA markers screening method and the 4-node directed competitive ceRNA-hub-FFL network constructed in this work can provide new ideas for screening tumor markers and understanding tumor development mechanisms in depth.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , MicroARNs , ARN Largo no Codificante , Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Escamosas/patología , Redes Reguladoras de Genes , Humanos , Neoplasias Pulmonares/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , Factores de Transcripción/genética
18.
Nano Lett ; 22(21): 8463-8469, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36301844

RESUMEN

Efficient hot electron extraction is a promising approach to develop photovoltaic devices that exceed the Shockley-Queisser limit. However, experimental evidence of hot electron harvesting employing an organic-inorganic interface is still elusive. Here, we reveal the hot electron dynamics at a CuPc/MoSe2 interface using steady-state spectroscopy and transient absorption spectroscopy. A hot electron transfer efficiency of greater than 78% from MoSe2 to CuPc is observed, comparable to that achieved in quantum dot hybrid systems. The mechanism is proposed as follows: the photogenerated hot electrons in MoSe2 transfer to CuPc and form singlet charge transfer states, which subsequently transform into triplet charge transfer states assisted by the rapid intersystem crossing, inhibiting back-donation of electrons and facilitating exciton dissociation into CuPc polarons with a nanosecond lifetime. Our results demonstrate that the intersystem crossing of the hybrid electronic state at organic-inorganic interfaces may serve as a scheme to enable efficient hot electron extraction in photovoltaic devices.

19.
Sci Adv ; 8(36): eabq5108, 2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36083908

RESUMEN

Nucleotide-binding, leucine-rich repeat receptors (NLRs) perceive pathogen effectors to trigger plant immunity. The direct recognition mechanism of pathogen effectors by coiled-coil NLRs (CNLs) remains unclear. We demonstrate that the Triticum monococcum CNL Sr35 directly recognizes the pathogen effector AvrSr35 from Puccinia graminis f. sp. tritici and report a cryo-electron microscopy structure of Sr35 resistosome and a crystal structure of AvrSr35. We show that AvrSr35 forms homodimers that are disassociated into monomers upon direct recognition by the leucine-rich repeat domain of Sr35, which induces Sr35 resistosome assembly and the subsequent immune response. The first 20 amino-terminal residues of Sr35 are indispensable for immune signaling but not for plasma membrane association. Our findings reveal the direct recognition and activation mechanism of a plant CNL and provide insights into biochemical function of Sr35 resistosome.

20.
Dermatol Ther ; 35(10): e15711, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35818112

RESUMEN

To investigate the diagnostic value of dermoscopy in defining the tumor margin of basal cell carcinoma (BCC) for the appropriate surgical margin. A total of 107 BCC patients were enrolled for this study. The tumor boundaries were observed by naked eye and dermoscope respectively, and 5 mm outward was used as surgical margin according to the dermoscopy-defined margin. Pathological examinations were performed at 2 mm intervals in the direction previously marked and the effect was assessed accordingly. There were still 16.8% of patients whose visual margin was insufficient to the dermoscopy-detected margin. With 2 mm excision margin from the dermoscopy-guided tumor margin, excision range in 12 patients (11.2%) proved to be inadequate, but only 18 surgical margins (4.2%) in the whole 428 excision margin specimens proved to be tumor-positive. While with 4 mm margin, residual lesion was observed in 2 (0.5%) of 107 BCC patients, and positive margin was found in 2 (0.3%) of 428 margin specimen. There has been no recurrence in our study so far. Dermoscopy is superior to visual inspection for defining BCC tumor margin. Under preoperative dermoscopy detection, a 4 mm excision margin of BCC can achieve a radical resection rate of 98.1%, and 92.3% for a 2 mm excision margin of pigmented BCC.


Asunto(s)
Carcinoma Basocelular , Neoplasias Cutáneas , Carcinoma Basocelular/diagnóstico por imagen , Carcinoma Basocelular/cirugía , Dermoscopía , Humanos , Márgenes de Escisión , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias Cutáneas/cirugía
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