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1.
Biomed Phys Eng Express ; 10(5)2024 Jul 17.
Article in English | MEDLINE | ID: mdl-38925106

ABSTRACT

Detecting the Kirsten Rat Sarcoma Virus (KRAS) gene mutation is significant for colorectal cancer (CRC) patients. TheKRASgene encodes a protein involved in the epidermal growth factor receptor (EGFR) signaling pathway, and mutations in this gene can negatively impact the use of monoclonal antibodies in anti-EGFR therapy and affect treatment decisions. Currently, commonly used methods like next-generation sequencing (NGS) identifyKRASmutations but are expensive, time-consuming, and may not be suitable for every cancer patient sample. To address these challenges, we have developedKRASFormer, a novel framework that predictsKRASgene mutations from Haematoxylin and Eosin (H & E) stained WSIs that are widely available for most CRC patients.KRASFormerconsists of two stages: the first stage filters out non-tumor regions and selects only tumour cells using a quality screening mechanism, and the second stage predicts theKRASgene either wildtype' or mutant' using a Vision Transformer-based XCiT method. The XCiT employs cross-covariance attention to capture clinically meaningful long-range representations of textural patterns in tumour tissue andKRASmutant cells. We evaluated the performance of the first stage using an independent CRC-5000 dataset, and the second stage included both The Cancer Genome Atlas colon and rectal cancer (TCGA-CRC-DX) and in-house cohorts. The results of our experiments showed that the XCiT outperformed existing state-of-the-art methods, achieving AUCs for ROC curves of 0.691 and 0.653 on TCGA-CRC-DX and in-house datasets, respectively. Our findings emphasize three key consequences: the potential of using H & E-stained tissue slide images for predictingKRASgene mutations as a cost-effective and time-efficient means for guiding treatment choice with CRC patients; the increase in performance metrics of a Transformer-based model; and the value of the collaboration between pathologists and data scientists in deriving a morphologically meaningful model.


Subject(s)
Colorectal Neoplasms , Mutation , Proto-Oncogene Proteins p21(ras) , Humans , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Proto-Oncogene Proteins p21(ras)/genetics , Algorithms , ErbB Receptors/genetics , High-Throughput Nucleotide Sequencing/methods , Image Processing, Computer-Assisted/methods , ROC Curve
2.
Chem Asian J ; : e202400138, 2024 May 11.
Article in English | MEDLINE | ID: mdl-38733617

ABSTRACT

The aminotroponiminate (ATI) ligand stabilized germylene cation [(i-Bu)2ATIGe][B(C6F5)4] (2) is found to be an efficient low-valent main-group catalyst for the cyanosilylation of aldehydes and ketones (ATI=aminotroponiminate). It was synthesized by reacting [(i-Bu)2ATIGeCl] (1) with Na[B(C6F5)4]. The catalytic cyanosilylation of diverse aliphatic and aromatic carbonyl compounds (aldehydes and ketones) using 0.075-0.75 mol% of compound 2 was completed within 5-45 min. The catalytic efficiency seen with aliphatic aldehydes was around 15,800 h-1, making compound 2 a capable low-valent main-group catalyst for the aldehyde and ketone cyanosilylation reactions. Further, DFT calculations reveal a pronounced charge localization at the germanium atom of compound 2, leading to its superior catalytic performance.

3.
J Kidney Cancer VHL ; 11(2): 18-26, 2024.
Article in English | MEDLINE | ID: mdl-38799379

ABSTRACT

To analyze and compare the intraoperative and post-operative outcomes of "on-clamp" laparoscopic partial nephrectomy (LPN) with "preoperative super-selective angioembolization" before LPN. This randomized clinical study was conducted at Gauhati Medical College Hospital, Guwahati, India, between November 2021 and November 2023. Adult patients of either gender diagnosed with T1 renal tumors were included in the study. All patients underwent diethylenetriamine pentaacetate scan preoperatively and at 1-month follow-up. The patients were randomized using a parallel group design with an allocation ratio of 1:1 to receive either preoperative angioembolization followed by LPN or conventional "on-clamp" LPN. Demographic and baseline parameters were recorded along with pre- and post-operative data. There was no significant difference between the two groups in terms of age (P = 0.11), gender distribution (P = 0.32), body mass index (P = 0.43), preoperative hemoglobin (P = 0.34), and preoperative estimated glomerular filtration rate (eGFR; P = 0.64). One patient in the embolization group required radical nephrectomy because of accidental backflow of glue into the renal artery during embolization whereas four patients required clamping due to inadequate embolization. Preoperative super-selective embolization yielded significantly less blood loss, compared to "on-clamp" LPN (145 [50.76 mL] vs. 261 [66.12 mL], P < 0.01). There was no significant difference between post-operative eGFR (at 1 month) between the two groups (P = 0.71). Preoperative embolization offers improved outcomes in the dissection plane, total operative time, and blood loss, compared to conventional "on-clamp" LPN but has no significant effect on change in eGFR.

4.
Dig Endosc ; 2024 May 02.
Article in English | MEDLINE | ID: mdl-38695110

ABSTRACT

Endoscopic ultrasound (EUS) is increasingly used as a therapeutic approach for gastrointestinal diseases, especially with the advent of lumen-apposing metal stents (LAMS). This has led to a rise in of EUS-guided gastrointestinal anastomosis procedures. Due to the reliability of intestinal conduits with LAMS, indications for EUS-guided gastrointestinal anastomosis are becoming more common and trend to potentially be standard care for gastric outlet obstruction, afferent loop syndrome, and EUS-directed transgastric interventions such as EUS-directed endoscopic retrograde cholangiopancreatography. Retrospective and prospective data indicate that the procedure is becoming widely adopted with promising outcomes. This article aims to review the existing literature on EUS-guided gastrointestinal anastomosis and predict its future developments.

5.
Int J Lab Hematol ; 46(4): 646-656, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38456256

ABSTRACT

INTRODUCTION: Despite extensive research, comprehensive characterization of leukaemic stem cells (LSC) and information on their immunophenotypic differences from normal haematopoietic stem cells (HSC) is lacking. Herein, we attempted to unravel the immunophenotypic (IPT) characteristics and heterogeneity of LSC using multiparametric flow cytometry (MFC) and single-cell sequencing. MATERIALS AND METHODS: Bone marrow aspirate samples from patients with acute myeloid leukaemia (AML) were evaluated using MFC at diagnostic and post induction time points using a single tube-10-colour-panel containing LSC-associated antibodies CD123, CD45RA, CD44, CD33 and COMPOSITE (CLL-1, TIM-3, CD25, CD11b, CD22, CD7, CD56) with backbone markers that is, CD45, CD34, CD38, CD117, sCD3. Single-cell sequencing of the whole transcriptome was also done in a bone marrow sample. RESULTS: LSCs and HSCs were identified in 225/255 (88.2%) and 183/255 (71.6%) samples, respectively. Significantly higher expression was noted for COMPOSITE, CD45RA, CD123, CD33, and CD44 in LSCs than HSCs (p < 0.0001). On comparing the LSC specific antigen expressions between CD34+ (n = 184) and CD34- LSCs (n = 41), no difference was observed between the groups. More than one sub-population of LSC was demonstrated in 4.4% of cases, which further revealed high concordance between MFC and single cell transcriptomic analysis in one of the cases displaying three LSC subpopulations by both methods. CONCLUSION: A single tube-10-colour MFC panel is proposed as an easy and reproducible tool to identify and discriminate LSCs from HSCs. LSCs display both inter- and intra-sample heterogeneity in terms of antigen expressions, which opens the facets for single cell molecular analysis to elucidate the role of subpopulations of LSCs in AML progression.


Subject(s)
Flow Cytometry , Immunophenotyping , Leukemia, Myeloid, Acute , Neoplastic Stem Cells , Humans , Leukemia, Myeloid, Acute/diagnosis , Leukemia, Myeloid, Acute/pathology , Leukemia, Myeloid, Acute/metabolism , Flow Cytometry/methods , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Male , Female , Adult , Middle Aged , Single-Cell Analysis/methods , Antigens, CD/metabolism , Antigens, CD/analysis , Aged
6.
Molecules ; 29(4)2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38398638

ABSTRACT

The high concentration of antibiotics in aquatic environments is a serious environmental issue. In response, researchers have explored photocatalytic degradation as a potential solution. Through chemical vapor deposition (CVD), we synthesized copper selenide (ß-Cu2-xSe) and found it an effective catalyst for degrading tetracycline hydrochloride (TC-HCl). The catalyst demonstrated an impressive degradation efficiency of approximately 98% and a reaction rate constant of 3.14 × 10-2 min-1. Its layered structure, which exposes reactive sites, contributes to excellent stability, interfacial charge transfer efficiency, and visible light absorption capacity. Our investigations confirmed that the principal active species produced by the catalyst comprises O2- radicals, which we verified through trapping experiments and electron paramagnetic resonance (EPR). We also verified the TC-HCl degradation mechanism using high-performance liquid chromatography-mass spectrometry (LC-MS). Our results provide valuable insights into developing the ß-Cu2-xSe catalyst using CVD and its potential applications in environmental remediation.

7.
Comput Struct Biotechnol J ; 23: 174-185, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38146436

ABSTRACT

The immune response associated with oncogenesis and potential oncological ther- apeutic interventions has dominated the field of cancer research over the last decade. T-cell lymphocytes in the tumor microenvironment are a crucial aspect of cancer's adaptive immunity, and the quantification of T-cells in specific can- cer types has been suggested as a potential diagnostic aid. However, this is cur- rently not part of routine diagnostics. To address this challenge, we present a new method called True-T, which employs artificial intelligence-based techniques to quantify T-cells in colorectal cancer (CRC) using immunohistochemistry (IHC) images. True-T analyses the chromogenic tissue hybridization signal of three widely recognized T-cell markers (CD3, CD4, and CD8). Our method employs a pipeline consisting of three stages: T-cell segmentation, density estimation from the segmented mask, and prediction of individual five-year survival rates. In the first stage, we utilize the U-Net method, where a pre-trained ResNet-34 is em- ployed as an encoder to extract clinically relevant T-cell features. The segmenta- tion model is trained and evaluated individually, demonstrating its generalization in detecting the CD3, CD4, and CD8 biomarkers in IHC images. In the second stage, the density of T-cells is estimated using the predicted mask, which serves as a crucial indicator for patient survival statistics in the third stage. This ap- proach was developed and tested in 1041 patients from four reference diagnostic institutions, ensuring broad applicability. The clinical effectiveness of True-T is demonstrated in stages II-IV CRC by offering valuable prognostic information that surpasses previous quantitative gold standards, opening possibilities for po- tential clinical applications. Finally, to evaluate the robustness and broader ap- plicability of our approach without additional training, we assessed the universal accuracy of the CD3 component of the True-T algorithm across 13 distinct solid tumors.

8.
Med J Armed Forces India ; 79(Suppl 1): S311-S314, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38144624

ABSTRACT

Recurrent tracheoesophageal fistula is a rare complication of esophageal atresia surgery with an incidence of 3-15%. The presentation is subtle and is often missed, presenting as choking episodes during feed and recurrent chest infections. It is both a diagnostic and management challenge and requires a dedicated multidisciplinary pediatric surgical setup with adequate infrastructure for optimal management. We present a case of recurrent tracheoesophageal fistula which was diagnosed at our center. The patient underwent successful surgical management and is thriving well at six months follow-up period.

9.
Article in English | MEDLINE | ID: mdl-37665699

ABSTRACT

Monitoring the healthy development of a fetus requires accurate and timely identification of different maternal-fetal structures as they grow. To facilitate this objective in an automated fashion, we propose a deep-learning-based image classification architecture called the COMFormer to classify maternal-fetal and brain anatomical structures present in 2-D fetal ultrasound (US) images. The proposed architecture classifies the two subcategories separately: maternal-fetal (abdomen, brain, femur, thorax, mother's cervix (MC), and others) and brain anatomical structures [trans-thalamic (TT), trans-cerebellum (TC), trans-ventricular (TV), and non-brain (NB)]. Our proposed architecture relies on a transformer-based approach that leverages spatial and global features using a newly designed residual cross-variance attention block. This block introduces an advanced cross-covariance attention (XCA) mechanism to capture a long-range representation from the input using spatial (e.g., shape, texture, intensity) and global features. To build COMFormer, we used a large publicly available dataset (BCNatal) consisting of 12 400 images from 1792 subjects. Experimental results prove that COMFormer outperforms the recent CNN and transformer-based models by achieving 95.64% and 96.33% classification accuracy on maternal-fetal and brain anatomy, respectively.


Subject(s)
Brain , Ultrasonography, Prenatal , Female , Pregnancy , Humans , Brain/diagnostic imaging , Ultrasonography , Electric Power Supplies , Femur
10.
Symbiosis ; : 1-15, 2023 Jun 08.
Article in English | MEDLINE | ID: mdl-37360552

ABSTRACT

The synthesis of secondary metabolites is a constantly functioning metabolic pathway in all living systems. Secondary metabolites can be broken down into numerous classes, including alkaloids, coumarins, flavonoids, lignans, saponins, terpenes, quinones, xanthones, and others. However, animals lack the routes of synthesis of these compounds, while plants, fungi, and bacteria all synthesize them. The primary function of bioactive metabolites (BM) synthesized from endophytic fungi (EF) is to make the host plants resistant to pathogens. EF is a group of fungal communities that colonize host tissues' intracellular or intercellular spaces. EF serves as a storehouse of the above-mentioned bioactive metabolites, providing beneficial effects to their hosts. BM of EF could be promising candidates for anti-cancer, anti-malarial, anti-tuberculosis, antiviral, anti-inflammatory, etc. because EF is regarded as an unexploited and untapped source of novel BM for effective drug candidates. Due to the emergence of drug resistance, there is an urgent need to search for new bioactive compounds that combat resistance. This article summarizes the production of BM from EF, high throughput methods for analysis, and their pharmaceutical application. The emphasis is on the diversity of metabolic products from EF, yield, method of purification/characterization, and various functions/activities of EF. Discussed information led to the development of new drugs and food additives that were more effective in the treatment of disease. This review shed light on the pharmacological potential of the fungal bioactive metabolites and emphasizes to exploit them in the future for therapeutic purposes.

11.
Chemosphere ; 313: 137524, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36509191

ABSTRACT

Increasing land degradation by high level of metal wastes is of prime concern for the global research communities. In this respect, halophytes having specific features like salt glands, exclusion of excess ions, heavy metals (HMs) compartmentalization, large pool of antioxidants, and associations with metal-tolerant microbes are of great promise in the sustainable clean-up of contaminated sites. However, sustainable clean-up of HMs by a particular halophyte plant species is governed considerably by physico-chemical characteristics of soil and associated microbial communities. The present review has shed light on the superiority of halophytes over non-halophytes, mechanisms of metal-remediation, recent developments and future perspectives pertaining to the utilization of halophytes in management of HM-contaminated sites with the aid of bibliometric analysis. The results revealed that the research field is receiving considerable attention in the last 5-10 years by publishing ∼50-90% documents with an annual growth rate of 15.41% and citations per document of 29.72. Asian (viz., China, India, and Pakistan) and European (viz., Spain, Portugal, Belgium, Argentina) countries have been emerged as the major regions conducting and publishing extensive research on this topic. The investigations conducted both under in vitro and field conditions have reflected the inherent potential of halophyte as sustainable research tool for successfully restoring the HM-contaminated sites. The findings revealed that the microbial association with halophytes under different challenging conditions is a win-win approach for metal remediation. Therefore, exploration of new halophyte species and associated microorganisms (endophytic and rhizospheric) from different geographical locations, and identification of genes conferring tolerance and phytoremediation of metal contaminants would further advance the intervention of halophytes for sustainable ecological restoration.


Subject(s)
Metals, Heavy , Soil Pollutants , Salt-Tolerant Plants/metabolism , Soil Pollutants/analysis , Metals, Heavy/analysis , Biodegradation, Environmental , Soil/chemistry
12.
Ann Hematol ; 102(1): 73-87, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36527458

ABSTRACT

To gain insights into the idiosyncrasies of CD34 + enriched leukemic stem cells, we investigated the nature and extent of transcriptional heterogeneity by single-cell sequencing in pediatric AML. Whole transcriptome analysis of 28,029 AML single cells was performed using the nanowell cartridge-based barcoding technology. Integrated transcriptional analysis identified unique leukemic stem cell clusters of each patient and intra-patient heterogeneity was revealed by multiple LSC-enriched clusters differing in their cell cycle processes and BCL2 expression. All LSC-enriched clusters exhibited gene expression profile of dormancy and self-renewal. Upregulation of genes involved in non-coding RNA processing and ribonucleoprotein assembly were observed in LSC-enriched clusters relative to HSC. The genes involved in regulation of apoptotic processes, response to cytokine stimulus, and negative regulation of transcription were upregulated in LSC-enriched clusters as compared to the blasts. Validation of top altered genes in LSC-enriched clusters confirmed upregulation of TCF7L2, JUP, ARHGAP25, LPAR6, and PRDX1 genes, and serine/threonine kinases (STK24, STK26). Upregulation of LPAR6 showed trend towards MRD positive status (Odds ratio = 0.126; 95% CI = 0.0144-1.10; p = 0.067) and increased expression of STK26 significantly correlated with higher RFS (HR = 0.231; 95% CI = 0.0506-1.052; p = 0.04). Our findings addressed the inter- and intra-patient diversity within AML LSC and potential signaling and chemoresistance-associated targets that warrant investigation in larger cohort that may guide precision medicine in the near future.


Subject(s)
Leukemia, Myeloid, Acute , Child , Humans , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/metabolism , Single-Cell Gene Expression Analysis , Antigens, CD34/metabolism , Gene Expression Profiling , Stem Cells/metabolism , Neoplastic Stem Cells/metabolism , Receptors, Lysophosphatidic Acid/genetics , Receptors, Lysophosphatidic Acid/metabolism
13.
Int J Hematol ; 117(1): 110-120, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36282419

ABSTRACT

Tyrosine kinase inhibitors (TKIs) are highly effective in treating chronic myelogenous leukemia (CML). However, primary and acquired drug resistance to TKIs have been reported. In this study, we used RNA sequencing followed by RQ-PCR to show that the proto-oncogene EVI1 targets the drug-metabolizing gene PTGS1 in CML. The PTGS1 promoter element had an EVI1 binding site, and CHIP assay confirmed its presence. Data from a publicly available CML microarray dataset and an independent set of CML samples showed a significant positive correlation between EVI1 and PTGS1 expression in CML. Downregulation of EVI1 in K562 cells and subsequent treatment with TKIs resulted in a lower IC50 in the control cells. Furthermore, combined inhibition of BCR-ABL with imatinib and PTGS1 with FR122047 (PTGS1 inhibitor) synergistically reduced the viability of imatinib-resistant K562 cells. We conclude that elevated EVI1 expression contributes to TKIs resistance and that combined inhibition of PTGS1 and BCR-ABL may represent a novel therapeutic approach.


Subject(s)
Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Humans , Apoptosis , Cyclooxygenase 1/pharmacology , Cyclooxygenase 1/therapeutic use , Drug Resistance, Neoplasm/genetics , Fusion Proteins, bcr-abl , Imatinib Mesylate/pharmacology , Imatinib Mesylate/therapeutic use , K562 Cells , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use
14.
Sci Total Environ ; 858(Pt 3): 159949, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36336036

ABSTRACT

Linkages of urban and industrial cooling with sustainable development goals and climate change perspectives are well acknowledged, mainly for developing economies in tropical climates. Angul-Talcher region is one of the oldest industrial clusters of India, and the region experiences higher atmospheric heat island intensities with magnitudes of 7 to 9 °C attributed to the Industrial Heat Island (IHI) effect. In the present study, various measures for mitigating heat island effect in the region and assessed their impact using an Improved Weather Research and Forecasting model coupled with the Single-Layer Urban Canopy Model. The improved framework includes the release of industrial emissions at stack height and sector-wise diurnal profiles of anthropogenic heat (AH) released from vehicles, residential, and industry/power. The mitigation measures comprised strategies like alteration in building materials and conversion of landuse-landcover (LULC) of selected grid cells in the model domain to more vegetation or water bodies. It was noted that the cool roofs and walls together reduced IHIs by 0.5 °C, while green roofs and cool pavements achieved a reduction of 0.3 °C and 0.1 °C, respectively. The introduction of water bodies showed maximum reduction in IHIs by 3 to 5 °C during daytime and 1 to 2 °C over mining and industrial stations. During night-time, conversion to mixed forests was more effective (ΔT ≈ 1 °C) than conversion to water bodies. A combination of cool roofs with the introduction of water bodies in the mining areas and mixed forest patches in industry stations was found to be the most effective mitigation strategy for mitigating the industrial heat island effect over the Angul-Talcher region. These mitigation scenarios can/should serve as a theoretical reference for implementing actual mitigation measures, which would require consideration of economic, social, and policy aspects apart from scientific ones for practical application.


Subject(s)
Hot Temperature , Water , Cities , India
15.
Diagnostics (Basel) ; 12(12)2022 Dec 02.
Article in English | MEDLINE | ID: mdl-36553031

ABSTRACT

Existing nuclei segmentation methods face challenges with hematoxylin and eosin (H&E) whole slide imaging (WSI) due to the variations in staining methods and nuclei shapes and sizes. Most existing approaches require a stain normalization step that may cause losing source information and fail to handle the inter-scanner feature instability problem. To mitigate these issues, this article proposes an efficient staining-invariant nuclei segmentation method based on self-supervised contrastive learning and an effective weighted hybrid dilated convolution (WHDC) block. In particular, we propose a staining-invariant encoder (SIE) that includes convolution and transformers blocks. We also propose the WHDC block allowing the network to learn multi-scale nuclei-relevant features to handle the variation in the sizes and shapes of nuclei. The SIE network is trained on five unlabeled WSIs datasets using self-supervised contrastive learning and then used as a backbone for the downstream nuclei segmentation network. Our method outperforms existing approaches in challenging multiple WSI datasets without stain color normalization.

16.
Diagnostics (Basel) ; 12(12)2022 Dec 18.
Article in English | MEDLINE | ID: mdl-36553220

ABSTRACT

Antral follicle Count (AFC) is a non-invasive biomarker used to assess ovarian reserves through transvaginal ultrasound (TVUS) imaging. Antral follicles' diameter is usually in the range of 2-10 mm. The primary aim of ovarian reserve monitoring is to measure the size of ovarian follicles and the number of antral follicles. Manual follicle measurement is inhibited by operator time, expertise and the subjectivity of delineating the two axes of the follicles. This necessitates an automated framework capable of quantifying follicle size and count in a clinical setting. This paper proposes a novel Harmonic Attention-based U-Net network, HaTU-Net, to precisely segment the ovary and follicles in ultrasound images. We replace the standard convolution operation with a harmonic block that convolves the features with a window-based discrete cosine transform (DCT). Additionally, we proposed a harmonic attention mechanism that helps to promote the extraction of rich features. The suggested technique allows for capturing the most relevant features, such as boundaries, shape, and textural patterns, in the presence of various noise sources (i.e., shadows, poor contrast between tissues, and speckle noise). We evaluated the proposed model on our in-house private dataset of 197 patients undergoing TransVaginal UltraSound (TVUS) exam. The experimental results on an independent test set confirm that HaTU-Net achieved a Dice coefficient score of 90% for ovaries and 81% for antral follicles, an improvement of 2% and 10%, respectively, when compared to a standard U-Net. Further, we accurately measure the follicle size, yielding the recall, and precision rates of 91.01% and 76.49%, respectively.

17.
Dalton Trans ; 51(44): 16906-16914, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-36301048

ABSTRACT

Two routes can offer the first stannylene cyanide [(L)SnCN] (5); the substitution reaction of either stannylene amide [(i-Bu)2ATISnN(SiMe3)2] (3) or stannylene pyrrolide [(i-Bu)2ATISn(NC4H4)] (4) using an excess of trimethylsilyl cyanide (L = aminotroponiminate (ATI)). Using 0.1-2.0 mol% of compound 5, catalytic cyanosilylation of a variety of aliphatic and aromatic aldehydes was achieved at rt-50 °C in 0.33-2.0 h. The mechanism of this catalytic reaction is authenticated by the isolation of a structurally characterized intermediate.

18.
Comput Biol Med ; 148: 105891, 2022 09.
Article in English | MEDLINE | ID: mdl-35932729

ABSTRACT

Deep learning has been widely utilized for medical image segmentation. The most commonly used U-Net and its variants often share two common characteristics but lack solid evidence for the effectiveness. First, each block (i.e., consecutive convolutions of feature maps of the same resolution) outputs feature maps from the last convolution, limiting the variety of the receptive fields. Second, the network has a symmetric structure where the encoder and the decoder paths have similar numbers of channels. We explored two novel revisions: a stacked dilated operation that outputs feature maps from multi-scale receptive fields to replace the consecutive convolutions; an asymmetric architecture with fewer channels in the decoder path. Two novel models were developed: U-Net using the stacked dilated operation (SDU-Net) and asymmetric SDU-Net (ASDU-Net). We used both publicly available and private datasets to assess the efficacy of the proposed models. Extensive experiments confirmed SDU-Net outperformed or achieved performance similar to the state-of-the-art while using fewer parameters (40% of U-Net). ASDU-Net further reduced the model parameters to 20% of U-Net with performance comparable to SDU-Net. In conclusion, the stacked dilated operation and the asymmetric structure are promising for improving the performance of U-Net and its variants.


Subject(s)
Image Processing, Computer-Assisted , Neural Networks, Computer
19.
Cancers (Basel) ; 14(16)2022 Aug 13.
Article in English | MEDLINE | ID: mdl-36010903

ABSTRACT

In this article, we propose ICOSeg, a lightweight deep learning model that accurately segments the immune-checkpoint biomarker, Inducible T-cell COStimulator (ICOS) protein in colon cancer from immunohistochemistry (IHC) slide patches. The proposed model relies on the MobileViT network that includes two main components: convolutional neural network (CNN) layers for extracting spatial features; and a transformer block for capturing a global feature representation from IHC patch images. The ICOSeg uses an encoder and decoder sub-network. The encoder extracts the positive cell's salient features (i.e., shape, texture, intensity, and margin), and the decoder reconstructs important features into segmentation maps. To improve the model generalization capabilities, we adopted a channel attention mechanism that added to the bottleneck of the encoder layer. This approach highlighted the most relevant cell structures by discriminating between the targeted cell and background tissues. We performed extensive experiments on our in-house dataset. The experimental results confirm that the proposed model achieves more significant results against state-of-the-art methods, together with an 8× reduction in parameters.

20.
Am J Trop Med Hyg ; 107(2): 349-354, 2022 08 17.
Article in English | MEDLINE | ID: mdl-35895401

ABSTRACT

The visceral leishmaniasis (VL) elimination program in Nepal has largely completed the attack phase and is moving toward consolidation and maintenance phases. New VL foci are, however, appearing in Nepal, and therefore new innovative community-centered strategies need to be developed and tested. We conducted early case detection by an index case-based approach and assessed the feasibility, efficacy, and cost of an intervention for sandfly control through indoor residual spraying (IRS) or insecticidal wall painting (IWP) in new and low-endemic districts Palpa and Surkhet. IRS was performed in 236 households and IWP in 178 households. We screened 1,239 and 596 persons in Palpa and Surkhet, respectively, resulting in the detection of one VL case in Palpa. Both IWP and IRS were well accepted, and the percentage reductions in sandfly density after 1, 9, and 12 months of intervention were 90%, 81%, and 75%, respectively, for IWP and 81%, 59%, and 63% respectively for IRS. The cost per household protected per year was USD 10.3 for IRS and 32.8 for IWP, although over a 2-year period, IWP was more cost-effective than IRS. Active case detection combined with sandfly control through IWP or IRS can support to VL elimination in the consolidation and maintenance phase.


Subject(s)
Insecticides , Leishmaniasis, Visceral , Phlebotomus , Psychodidae , Animals , Humans , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/epidemiology , Leishmaniasis, Visceral/prevention & control , Insect Control/methods , Nepal/epidemiology
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