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1.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(3): 294-299, 2024 Mar 10.
Artigo em Chinês | MEDLINE | ID: mdl-38448017

RESUMO

OBJECTIVE: To explore the clinical application of preimplantation genetic testing for monogenic disorders (PGT-M) in an unique case with Spinal muscular atrophy (SMA) type 2+0. METHODS: A special SMA family presented at the Third Affiliated Hospital of Guangzhou Medical University on October 19, 2020 was selected as the study subject. Multiple ligation-dependent probe amplification (MLPA) and molecular tagging linkage analysis were carried out to identify the SMN1 genotype of the couple and their fetus. Subsequently, next-generation sequencing (NGS), molecular tagging linkage analysis, and chromosomal microarray analysis were employed to determine the haplotypes and validate the result of PGT-M on the 11 embryos derived for the couple. RESULTS: The female partner was identified as a carrier of the rare SMN1[2+0] variant, and prenatal diagnosis confirmed the fetus to be affected by SMA. Ultimately, PGT-M has successfully selected four embryos free from the pathogenic SMN1 variants and X chromosome deletion. CONCLUSION: PGT-M can effectively prevent the transmission of rare genetic variants such as the SMA 2+0 subtype in the families. Above finding has provided guidance for genetic counseling and family planning for the couple.


Assuntos
Testes Genéticos , Atrofia Muscular Espinal , Gravidez , Feminino , Humanos , Atrofia Muscular Espinal/diagnóstico , Atrofia Muscular Espinal/genética , Genótipo , Aconselhamento Genético , Haplótipos
2.
Am J Surg Pathol ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38451836

RESUMO

Breast implant-associated anaplastic large cell lymphoma has been recognized as a distinct entity in the World Health Organization classification of hematolymphoid neoplasms. These neoplasms are causally related to textured implants that were used worldwide until recently. Consequently, there is an increased demand for processing periprosthetic capsules, adding new challenges for surgeons, clinicians, and pathologists. In the literature, the focus has been on breast implant-associated anaplastic large cell lymphoma; however, benign complications related to the placement of breast implants occur in up to 20% to 30% of patients. Imaging studies are helpful in assessing patients with breast implants for evidence of implant rupture, changes in tissues surrounding the implants, or regional lymphadenopathy related to breast implants, but pathologic examination is often required. In this review, we couple our experience with a review of the literature to describe a range of benign lesions associated with breast implants that can be associated with different clinical presentations or pathogenesis and that may require different diagnostic approaches. We illustrate the spectrum of the most common of these benign disorders, highlighting their clinical, imaging, gross, and microscopic features. Finally, we propose a systematic approach for the diagnosis and handling of breast implant specimens in general.

4.
Hum Pathol ; 146: 1-7, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38460798

RESUMO

Enhancer of zeste homolog 2 (EZH2) expression is found in about 40% of mantle cell lymphoma (MCL) patients, which is associated with aggressive histology, high Ki-67 proliferation rate, p53 mutant pattern and inferior overall survival (OS). We conducted 11-gene (ATM, BIRC3, CCND1, KMT2C, KMT2D, NOTCH1, NOTCH2, RB1, TP53, TRAF2 and UBR5) next generation sequencing panel to shed more light on MCL with EZH2 expression (EZH2+ MCL). EZH2+ MCL more frequently harbor TP53 mutation compared to EZH2(-) MCL (41.2% vs. 19.1%, respectively, p = 0.045). TP53 mutation and EZH2 expression demonstrated overlapping features including aggressive histology, high Ki-67 proliferation rate and p53 mutant pattern by immunohistochemistry. Comparative analysis disclosed that EZH2 expression correlates with high Ki-67 proliferation rate irrespective of TP53 mutation. Aggressive histology is associated with EZH2 expression or TP53 mutation, possibly via independent mechanisms. p53 mutant pattern is due to TP53 mutation. MCL patients with EZH2 expression or TP53 mutation show inferior outcome and when both are present, patients have dismal outcome.

6.
J Anesth ; 38(2): 222-231, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38305914

RESUMO

PURPOSE: This study aimed to compare non-invasive oscillometric blood pressure (NIBP) measurement with invasive arterial blood pressure (IBP) measurement in patients with sepsis. METHODS: We conducted a retrospective study to evaluate the agreement between IBP and NIBP using the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. Paired blood pressure measurements of mean arterial pressure (MAP), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were compared using Bland-Altman analysis and paired Student's t test. We also focus on the effect of norepinephrine (NE) on the agreement between the two methods and the association between blood pressure and mortality during intensive care unit (ICU) stay. RESULTS: A total of 96,673 paired blood pressure measurements from 6060 unique patients were analyzed in the study. In Bland-Altman analysis, the bias (± SD, 95% limits of agreement) was 6.21 mmHg (± 12.05 mmHg, - 17.41 to 29.83 mmHg) for MAP, 0.39 mmHg (± 19.25 mmHg, - 37.34 to 38.12 mmHg) for SBP, and 0.80 mmHg (± 12.92 mmHg, - 24.52 to 26.12 mmHg) for DBP between the two techniques. Similarly, large limits of agreement were shown in different groups of NE doses. NE doses significantly affected the agreement between IBP and NIBP. SBP between the two methods gave an inconsistent assessment of patients' risk of ICU mortality. CONCLUSION: IBP and NIBP were not interchangeable in septic patients. Clinicians should be aware that non-invasive MAP was clinically and significantly underestimated invasive MAP.


Assuntos
Pressão Arterial , Sepse , Humanos , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial/métodos , Estudos Retrospectivos , Norepinefrina , Sepse/diagnóstico , Monitores de Pressão Arterial
7.
Hum Pathol ; 144: 71-76, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38301962

RESUMO

Optical genome mapping (OGM) is a new DNA-based technology which provides comprehensive examination of the entire genome. We report two patients who presented with splenomegaly and leukocytosis with lymphocytosis including villous lymphocytes. Neither patient had lymphadenopathy. Bone marrow evaluation showed involvement by small B-cell lymphoma in a sinusoidal and interstitial distribution, and immunophenotypic analysis showed that the neoplastic cells were positive for B-cell markers and cyclin D1 but were negative for SOX11 and CD5. Initially, the clinicopathologic features in both patients were thought to be suspicious for hairy cell leukemia variant or splenic marginal zone lymphoma. However, OGM detected CCND1 rearrangement: t(2;11)/IGK::CCND1 in one case and t(11;14)/IGH::CCND1 in the other case. These cases illustrate the valuable role OGM can play in establishing the diagnosis of MCL. Case 1 also contributes to the paucity of literature on the rare occurrence of IGK::CCND1 in MCL.


Assuntos
Leucemia Linfocítica Crônica de Células B , Linfoma de Células B , Linfoma de Célula do Manto , Adulto , Humanos , Linfoma de Célula do Manto/patologia , Leucemia Linfocítica Crônica de Células B/patologia , Linfócitos/patologia , Genômica , Ciclina D1/genética
8.
Sci Rep ; 14(1): 686, 2024 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-38182722

RESUMO

High altitude exposure increases the risk of myocardial ischemia (MI) and subsequent cardiovascular death. Machine learning techniques have been used to develop cardiovascular disease prediction models, but no reports exist for high altitude induced myocardial ischemia. Our objective was to establish a machine learning-based MI prediction model and identify key risk factors. Using a prospective cohort study, a predictive model was developed and validated for high-altitude MI. We consolidated the health examination and self-reported electronic questionnaire data (collected between January and June 2022 in 920th Joint Logistic Support Force Hospital of china) of soldiers undergoing high-altitude training, along with the health examination and second self-reported electronic questionnaire data (collected between December 2022 and January 2023) subsequent to their completion on the plateau, into a unified dataset. Participants were subsequently allocated to either the training or test dataset in a 3:1 ratio using random assignment. A predictive model based on clinical features, physical examination, and laboratory results was designed using the training dataset, and the model's performance was evaluated using the area under the receiver operating characteristic curve score (AUC) in the test dataset. Using the training dataset (n = 2141), we developed a myocardial ischemia prediction model with high accuracy (AUC = 0.86) when validated on the test dataset (n = 714). The model was based on five laboratory results: Eosinophils percentage (Eos.Per), Globulin (G), Ca, Glucose (GLU), and Aspartate aminotransferase (AST). Our concise and accurate high-altitude myocardial ischemia incidence prediction model, based on five laboratory results, may be used to identify risks in advance and help individuals and groups prepare before entering high-altitude areas. Further external validation, including female and different age groups, is necessary.


Assuntos
Doença da Artéria Coronariana , Isquemia Miocárdica , Feminino , Humanos , Estudos de Coortes , Altitude , Estudos Prospectivos , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/etiologia , Aprendizado de Máquina
9.
Mod Pathol ; 37(2): 100405, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38104893

RESUMO

Large or blastoid B-cell neoplasms that are SOX11+ are a diagnostic dilemma and raise a differential diagnosis of cyclin D1-negative blastoid/pleomorphic mantle cell lymphoma (MCL) versus diffuse large B-cell lymphoma (DLBCL) or blastoid high-grade B-cell lymphoma (HGBL) with aberrant SOX11 expression. Here we report a study cohort of 13 SOX11+ large/blastoid B-cell neoplasms. Fluorescence in situ hybridization analysis was negative for CCND1 rearrangement in all 13 cases; 1 of 8 (12.5%) cases tested showed CCND2 rearrangement and 2 (25%) cases had extracopies of CCND2. Gene expression profiling showed that the study group had a gene expression signature similar to cyclin D1+ blastoid/pleomorphic MCL but different from DLBCL. Principal component analysis revealed that the cohort cases overlapped with cyclin D1+ blastoid/pleomorphic MCL but had minimal overlap with DLBCL. All patients in the cohort had clinicopathologic features similar to those reported for patients with cyclin D1+ MCL. We also performed a survey of SOX11 expression in a group of 85 cases of DLBCL and 24 cases of blastoid HGBL. SOX11 expression showed a 100% specificity and positive predictive value for the diagnosis of MCL. Overall, the results support the conclusion that large or blastoid B-cell neoplasms that are positive for SOX11 are best classified as cyclin D1-negative blastoid/pleomorphic MCL, and not as DLBCL or blastoid HGBL. We also conclude that SOX11 is a specific marker for the diagnosis of MCL, including cyclin D1-negative blastoid/pleomorphic MCL cases and should be performed routinely on blastoid/large B-cell neoplasms to help identify potential cases of cyclin D1-negative blastoid/pleomorphic MCL.


Assuntos
Linfoma Difuso de Grandes Células B , Linfoma de Célula do Manto , Adulto , Humanos , Linfoma de Célula do Manto/metabolismo , Ciclina D1/genética , Hibridização in Situ Fluorescente , Imuno-Histoquímica , Linfoma Difuso de Grandes Células B/patologia , Fatores de Transcrição SOXC/genética
10.
Cancers (Basel) ; 15(23)2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38067393

RESUMO

The aim of this study was to examine the cytogenetic profiles of plasma cell neoplasms (PCNs) at various disease stages, encompassing 1087 patients with monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM), newly diagnosed multiple myeloma (NDMM), and refractory/relapsed multiple myeloma (RRMM). Fluorescence in situ hybridization (FISH) analyses were conducted on highly purified plasma cell samples, revealing that 96% of patients exhibited at least one cytogenetic abnormality. The genomic complexity escalated from MGUS to SMM and further to NDMM and RRMM, largely driven by 1q gain, del(17p), MYC-rearrangement (MYC-R), del(1p), and tetraploidy. Elevated frequencies of high-risk cytogenetics (59%), 1q gain (44%), and del(17p) (23%), as well as the presence of subclones (48%), were particularly notable in RRMM cases. IGH::CCND1 was observed in 26% of the cases, with no apparent variations across races, ages, or disease groups. Concurrent chromosomal analysis with FISH revealed that the incidence of abnormal karyotypes was strongly correlated with the extent of neoplastic plasma cell infiltration, genomic complexity, and the presence of specific abnormalities like del(17p) and MYC-R. Approximately 98% of the cases with abnormal karyotypes were complex, with most featuring five or more abnormalities. Chromosome 1 structural abnormalities were the most prevalent, found in 65% of cases. The frequent presence of subclones and composite karyotypes underscored the genomic heterogeneity and instability in this cohort.

11.
Cell Mol Biol (Noisy-le-grand) ; 69(13): 102-105, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38158681

RESUMO

The objective of this study was to analyze the effect of curcumin (Cur) on pulmonary fibrosis (PF), so as to provide new clinical evidence for future PF treatment. To achieve these goals, the researchers set up bought human lung fibroblasts MRC-5 as a control group without treatment, a model group for PF cell modeling, and an intervention group for Cur intervention after PF modeling. Cell proliferation capacity and cellular TGF-ß1, α-SMA, Collagen I, Collagen III, Bax, N-cadherin and E-cadherin protein expression were determined. The results show that markedly enhanced cell proliferation capacity and TGF-ß1, α-SMA, Collagen I and Collagen III protein levels were observed in the model group, while the cell activity and fibrosis degree in the intervention group were significantly decreased compared with the model group (P<0.05). In addition, the intervention group exhibited lower N-cadherin and Bax with higher E-cadherin than the model group (P<0.05). In addition, the team found that the inflammatory response and oxidative stress were also more significantly improved in the intervention group (P<0.05). These experimental results tell us that Cur can ameliorate the fibrotic process of PF by inhibiting the activity of MRC-5.


Assuntos
Curcumina , Fibrose Pulmonar , Humanos , Fibrose Pulmonar/tratamento farmacológico , Fator de Crescimento Transformador beta1/metabolismo , Curcumina/farmacologia , Curcumina/uso terapêutico , Curcumina/metabolismo , Proteína X Associada a bcl-2/metabolismo , Fibrose , Pulmão/patologia , Colágeno/metabolismo , Fibroblastos/metabolismo , Colágeno Tipo I/metabolismo , Colágeno Tipo I/farmacologia , Colágeno Tipo I/uso terapêutico , Caderinas/metabolismo
13.
Mod Pathol ; 36(12): 100349, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37820764

RESUMO

A small subset of high-grade B-cell lymphoma (HGBL) with blastoid morphology remains poorly understood. We assessed 55 cases of blastoid HGBL, not otherwise specified (NOS) and compared their clinicopathologic characteristics with those of 81 non-blastoid HGBL-NOS and 62 blastoid HGBL with MYC and BCL2, with or without BCL6 rearrangements (double/triple-hit lymphoma [D/THL]). Patients with blastoid HGBL-NOS showed similar clinicopathologic features to patients with blastoid D/THLs and non-blastoid HGBL-NOS, except more frequently with a history of low-grade B-cell lymphoma, bone marrow involvement, and BCL2 rearrangement (P < .05) compared to the latter. MYC rearrangement (MYC-R), detected in 40% of blastoid HGBL-NOS, was associated with aggressive clinicopathologic features and poorer overall survival, even worse than that of blastoid D/THL (P < .05). Transcriptome profiling revealed a distinct gene expression pattern with differentially expressed genes enriched in MYC and P53-targeted genes in MYC-R blastoid HGBL-NOS. Fifty-two percent of blastoid HGBL-NOS had a double hit-like signature, similar to non-blastoid HGBL-NOS (P = .73). The overall survival of the blastoid HGBL-NOS group was similar to that of the blastoid D/THL group but appeared poorer than that of its non-blastoid counterparts (P = .07). Taken together, blastoid HGBL-NOS is an aggressive B-cell lymphoma that shares overlapping clinicopathologic and genetic features with non-blastoid HGBL-NOS. MYC-R in patients with blastoid HGBL-NOS identifies a highly aggressive subgroup with distinct aggressive clinicopathologic features, unique molecular signatures, and a dismal clinical outcome.


Assuntos
Linfoma de Células B , Linfoma Difuso de Grandes Células B , Humanos , Rearranjo Gênico , Linfoma de Células B/patologia , Proteínas Proto-Oncogênicas c-myc/genética , Biomarcadores Tumorais/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Linfoma Difuso de Grandes Células B/patologia , Proteínas Proto-Oncogênicas c-bcl-6/genética
14.
Nat Aging ; 3(11): 1387-1400, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37884767

RESUMO

DNA methylation deregulation at partially methylated domains (PMDs) represents an epigenetic signature of aging and cancer, yet the underlying molecular basis and resulting biological consequences remain unresolved. We report herein a mechanistic link between disrupted DNA methylation at PMDs and the spatial relocalization of H3K9me3-marked heterochromatin in aged hematopoietic stem and progenitor cells (HSPCs) or those with impaired DNA methylation. We uncover that TET2 modulates the spatial redistribution of H3K9me3-marked heterochromatin to mediate the upregulation of endogenous retroviruses (ERVs) and interferon-stimulated genes (ISGs), hence contributing to functional decline of aged HSPCs. TET2-deficient HSPCs retain perinuclear distribution of heterochromatin and exhibit age-related clonal expansion. Reverse transcriptase inhibitors suppress ERVs and ISGs expression, thereby restoring age-related defects in aged HSPCs. Collectively, our findings deepen the understanding of the functional interplay between DNA methylation and histone modifications, which is vital for maintaining heterochromatin function and safeguarding genome stability in stem cells.


Assuntos
Células-Tronco Hematopoéticas , Heterocromatina , Heterocromatina/genética , Células-Tronco Hematopoéticas/metabolismo , Metilação de DNA/genética
15.
Blood Adv ; 7(24): 7393-7401, 2023 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-37874912

RESUMO

Mantle cell lymphoma (MCL) is a B-cell non-Hodgkin lymphoma; data indicate that blastoid and pleomorphic variants have a poor prognosis. We report characteristics and outcomes of patients with blastoid/pleomorphic variants of MCL. We retrospectively studied adults with newly diagnosed MCL treated from 2000 to 2015. Primary objectives were to describe progression-free survival (PFS) and overall survival (OS). Secondary objectives included characterization of patient characteristics and treatments. Of the 1029 patients with MCL studied, a total of 207 neoplasms were blastoid or pleomorphic variants. Median follow-up period was 82 months (range, 0.1-174 months); median PFS was 38 months (95% confidence interval [CI], 28-66) and OS was 68 months (95% CI, 45-96). Factors associated with PFS were receipt of consolidative autologous hematopoietic transplantation (auto-HCT; hazard ratio [HR], 0.52; 95% CI, 0.31-0.80; P < .05), MCL International Prognostic Index (MIPI) intermediate (HR, 2.3; 95% CI, 1.2-4.3; P < .02) and high (HR, 3.8; 95% CI, 2.0-7.4; P < .01) scores, and complete response to induction (HR, 0.29 (95% CI, 0.17-0.51). Receipt of auto-HCT was not associated with OS (HR, 0.69; 95% CI, 0.41-1.16; P = .16) but was associated with MIPI intermediate (HR, 5.7; 95% CI, 2.5-13.2; P < .01) and high (HR, 10.8; 95% CI, 4.7-24.9; P < .01) scores. We report outcomes in a large cohort of patients with blastoid/pleomorphic variant MCL. For eligible patients, receipt of auto-HCT after induction was associated with improved PFS but not OS. Higher MIPI score and auto-HCT ineligibility were associated with worse survival.


Assuntos
Linfoma de Célula do Manto , Adulto , Humanos , Linfoma de Célula do Manto/terapia , Linfoma de Célula do Manto/tratamento farmacológico , Estudos Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Medição de Risco , Intervalo Livre de Progressão
16.
Neurobiol Dis ; 187: 106320, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37813166

RESUMO

Age-related hearing loss (ARHL) is a prevalent condition affecting millions of individuals globally. This study investigated the role of the cell survival regulator Bcl2 in ARHL through in vitro and in vivo experiments and metabolomics analysis. The results showed that the lack of Bcl2 in the auditory cortex affects lipid metabolism, resulting in reduced synaptic function and neurodegeneration. Immunohistochemical analysis demonstrated enrichment of Bcl2 in specific areas of the auditory cortex, including the secondary auditory cortex, dorsal and ventral areas, and primary somatosensory cortex. In ARHL rats, a significant decrease in Bcl2 expression was observed in these areas. RNAseq analysis showed that the downregulation of Bcl2 altered lipid metabolism pathways within the auditory pathway, which was further confirmed by metabolomics analysis. These results suggest that Bcl2 plays a crucial role in regulating lipid metabolism, synaptic function, and neurodegeneration in ARHL; thereby, it could be a potential therapeutic target. We also revealed that Bcl2 probably has a close connection with lipid peroxidation and reactive oxygen species (ROS) production occurring in cochlear hair cells and cortical neurons in ARHL. The study also identified changes in hair cells, spiral ganglion cells, and nerve fiber density as consequences of Bcl2 deficiency, which could potentially contribute to the inner ear nerve blockage and subsequent hearing loss. Therefore, targeting Bcl2 may be a promising potential therapeutic intervention for ARHL. These findings provide valuable insights into the molecular mechanisms underlying ARHL and may pave the way for novel treatment approaches for this prevalent age-related disorder.


Assuntos
Presbiacusia , Animais , Ratos , Envelhecimento/metabolismo , Envelhecimento/patologia , Metabolismo dos Lipídeos , Neurônios , Presbiacusia/metabolismo , Presbiacusia/patologia , Gânglio Espiral da Cóclea
17.
Cytometry B Clin Cytom ; 104(5): 356-366, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37605812

RESUMO

BACKGROUND: Acute myeloid leukemia (AML) minimal/measurable residual disease (MRD) by multicolor flow cytometry is a complex laboratory developed test (LDT), challenging for implementation. We share our experience in the validation of a 12-color AML MRD flow cytometry assay to meet stringent regulatory requirements. METHODS: We worked under the guidelines of the CLSI HL62 publication, illustrated the details of the validation process that was tailored to uniqueness of AML MRD, and tested its clinical validity in 61 patients. The "trueness" was determined by correlating with concurrent molecular genetic testing and follow-up bone marrow examinations. RESULTS: Under assay specificity, we shared the details of panel design, analysis, and criteria for interpretation and reporting. The assay accuracy was assessed by testing known positive and negative samples and correlating with molecular genetic testing and follow-up bone marrow examination. The limit of detection (LOD) and limit of quantification (LOQ) were validated to a level between 0.01% and 0.1%, varied from the leukemia-associated immunophenotypes (LAIP) and the numbers of events obtained for analysis. Assay linearity, precision and carry over studies all met acceptable criteria. In the clinical validity test, the concordance was 93%, specificity 98% and sensitivity 83%. The most challenging aspects of the assay were the discrimination of pre-leukemic cells (persistent clonal hematopoiesis) or underlying myelodysplastic clones from AML MRD with immunophenotypic switch or subclone selection. CONCLUSION: The validation met all criteria and obtained FDA IDE (investigational device exemption) approval. This study provides ample technical and professional details in setting up the AML MRD flow cytometry assay and illustrates through the example of the "fit for purpose" validation process. We also highlight the need for further characterization of abnormal blasts bearing the potential for AML relapse.

20.
Opt Express ; 31(12): 19453-19462, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381360

RESUMO

To accurately measure the local temperatures of the micro-nano area, we propose an optical method using a tapered fiber Bragg grating (FBG) probe with a nano tip for scanning probe microscopy (SPM). When the tapered FBG probe senses local temperature through near-field heat transfer, the intensity of the reflected spectrum decreases, along with a broadening bandwidth and a shift in the central peak position. Modeling the heat transfer between the probe and the sample shows that the tapered FBG probe is in a non-uniform temperature field when approaching the sample surface. Simulation of the probe's reflection spectrum reveals that the central peak position shifts nonlinearly with increasing local temperature. In addition, the near-field temperature calibration experiments show that the temperature sensitivity of the FBG probe increases nonlinearly from 6.2 pm/°C to 9.4 pm/°C as the sample surface temperature increases from 25.3°C to 160.4°C. The agreement of the experimental results with the theory and the reproducibility demonstrate that this method offers a promising approach for exploring micro-nano temperature.

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