ImmunoPET imaging of Trop2 expression in solid tumors with nanobody tracers.

PURPOSE: The high expression of the transmembrane glycoprotein trophoblast cell-surface antigen 2 (Trop2) was strongly associated with the progression of solid tumors, including pancreatic and gastric cancers. Our study aimed to construct Trop2-specific immuno-positron emission tomography (immunoPET) probes and assess the diagnostic abilities in preclinical pancreatic and gastric cancer models. METHODS: The expression of Trop2 in pancreatic cancer was determined by single-cell sequencing and immunohistochemistry on tissue microarray (TMA). Flow cytometry was used to screen the expression of Trop2 in pancreatic cancer cell lines. Two nanobodies (i.e., RTD98 and RTD01) targeting Trop2 were developed and labeled with gallium-68 (68Ga, T1/2 = 1.1 h) to construct immunoPET imaging probes. The agents were researched in cell-derived pancreatic and patient-derived gastric cancer models expressing varying Trop2. RESULTS: Single-cell sequencing results showed high expression of Trop2 in pancreatic ductal cells as well as acinar cells and immunohistochemical staining of TMA from pancreatic cancers showed significantly higher expression of Trop2 in cancerous than in paracancerous tissues. ImmunoPET utilizing [68Ga]Ga-NOTA-RTD98 could clearly delineate subcutaneous tumors, both in cell-derived pancreatic cancer models and patient-derived gastric cancer models, superior to imaging using [18F]-FDG or a non-specific probe [68Ga]Ga-NOTA-RTD161. Another probe with improved pharmacokinetics targeting Trop2, [68Ga]Ga-NOTA-RTD01, was further prepared and showed advantageous diagnostic capabilities in preclinical pancreatic cancer models. CONCLUSION: In the work, we reported two nanobody tracers targeting human Trop2 which may facilitate better use of Trop2-targeted therapeutics by noninvasively displaying expression dynamics of the target.

Locating Three-Dimensional Position of Deep-Seated SERS Phantom Lesions in Thick Tissues Using Tomographic Transmission Raman Spectroscopy.

Locating distinct objects within a thick scattering medium remains a long-standing challenge in the fields of materials science, health, and engineering. Transmission Raman spectroscopy (TRS) with the use of surface-enhanced Raman scattering (SERS) nanoparticles has proven to be an effective approach to detect deep-seated lesions inside thick biological tissues. However, it has not yet been proven to spatially locate deep lesions in three dimensions using optical modalities. Herein, we present the concept of tomographic TRS and report its successful use for accurately locating SERS nanoparticles in elongated rod-like thick tissues. Our work starts with theoretical simulations of Raman photon propagation in tissues. We discovered a linear relationship between the Raman spectral peak ratio and propagation distance of Raman photons in tissues, allowing us to predict the location of lesions tagged by SERS NPs. Based on this, we propose a two-step tomographic TRS strategy, which includes axial scanning and ring scanning. We demonstrate the robustness of our approach using ex vivo thick tissue (4.5 cm in thickness) and locate an embedded SERS phantom lesion, with a ring scanning step of 10-30°. We successfully locate multiple SERS phantom lesions in the ex vivo porcine muscle stack with high accuracy (absolute error of <2 mm). Our method is rapid, efficient, and of low cost compared to current tomographic medical imaging techniques. This work advances Raman techniques for three-dimensional positioning and offers new insights toward practical diagnosis applications.

Aberrant HPO Axis Alterations and Autoimmune Abnormalities in PCOS Patients with DOR: A Retrospective Analysis.

BACKGROUND: There is a group of polycystic ovary syndrome (PCOS) patients in clinic who have diminished ovarian reserve (DOR) in combination. This study was designed to evaluate the differences in glucolipid metabolism, hypothalamic-pituitary-ovarian (HPO) axis-related parameters, and autoimmune antibodies in PCOS patients with and without DOR. METHODS: A total of 2307 PCOS patients, including 1757 patients with PCOS alone and 550 patients who have both PCOS and DOR, were enrolled in this retrospective study. Parameters of glucolipid metabolism, HPO axis-related parameters, and autoimmune antibodies were measured and analyzed. RESULTS: The prevalence of DOR among all patients with PCOS was 23.84%. Many HPO axis-related parameters, such as follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), and prolactin (PRL) were significantly different in PCOS with DOR compared with PCOS without DOR. The FSH levels were positively correlated with LH, testosterone (T), and androstenedione (AD) levels, but had no association with glucolipid metabolism after adjusting for body mass index (BMI). Moreover, anti-ovarian antibody (AOAb) and anti-21-OH antibody (21-OHAb) levels were significantly elevated in PCOS patients with DOR. CONCLUSIONS: PCOS patients with DOR showed more chaotic HPO axis hormone levels and elevated autoimmune antibodies, suggesting that autoimmune factors may be the cause of DOR in women with PCOS.

Interfacial Self-Assembly of Surfactant-Free Au Nanoparticles as a Clean Surface-Enhanced Raman Scattering Substrate for Quantitative Detection of As5+ in Combination with Convolutional Neural Networks.

Surface-enhanced Raman scattering (SERS) is a highly sensitive tool in the field of environmental testing. However, the detection and accurate quantification of weakly adsorbed molecules (such as heavy metal ions) remain a challenge. Herein, we combine clean SERS substrates capable of capturing heavy metal ions with convolutional neural network (CNN) algorithm models for quantitative detection of heavy metal ions in solution. The SERS substrate consists of surfactant-free Au nanoparticles (NPs) and l-cysteine molecules. As plasmonic nanobuilt blocks, surfactant-free Au NPs without physical or chemical barriers are more accessible to target molecules. The amino and carboxyl groups in the l-cysteine molecule can chelate As5+ ions. The CNN algorithm model is applied to quantify and predict the concentration of As5+ ions in samples. The results demonstrated that this strategy allows for fast and accurate prediction of As5+ ion concentrations, and the determination coefficient between the predicted and actual values is as high as 0.991.

Superior biocompatible carbon dots for dynamic fluorescence imaging of nucleoli in living cells.

The nucleolus is a newly developed and promising target for cancer diagnosis and therapy, and its imaging is extremely significant for fundamental research and clinical applications. The unique feature, i.e., high resolution at the subcellular level, makes the fluorescence imaging method a powerful tool for nucleolus imaging. However, the fluorescence imaging of nucleoli in living cells is restricted by the limited availability of fluorescent agents with specific nucleolus-targeting capability and superior biocompatibility. Here, promising carbon dots (CDs) with intrinsic nucleolus-targeting capability were synthesized, characterized and employed for dynamic fluorescence imaging of nucleoli in living cells. The CDs exhibit a high fluorescence quantum yield of 0.2, excellent specificity and photostability, and superior biocompatibility, which were systematically demonstrated at the gene, cellular and animal levels and confirmed by their biological effects on embryonic development. All these features enabled CDs to light up the nucleoli for a long time with a high signal-to-noise ratio in living cells and monitor the nucleolar dynamics of malignant cells in camptothecin (CPT) based chemotherapy. Their excellent optical and biological features as well as general nucleolus-targeting capability endow CDs with great potential for future translational research.

Hyperandrogenism caused by a rare adrenocortical oncocytic neoplasm with uncertain malignant potential: a case report and review of the literature.

Hyperandrogenism is a state of androgen excess that can induce hirsutism and oligo/amenorrhea in women of reproductive age. Therapeutic strategies differ according to etiology. Hence, the differential diagnosis of hyperandrogenism is crucial. The adrenal gland is an important organ that produces androgens. One common cause of hyperandrogenism is androgen-secreting adrenal tumors; however, adrenocortical oncocytic neoplasms (ACONs) are rare. A 23-year-old woman presented with severe hirsutism and menstrual disorders for 2 years. Her Ferriman-Gallway hirsutism score was 15 at her first consultation. Her menstrual cycles were irregular, and her menstrual flow had diminished gradually over the past 2 years. She had a remarkable elevation of total testosterone, dehydroepiandrosterone sulfate and androstenedione. Pelvic ultrasonography showed normal morphology of the uterus and bilateral ovaries. Computed tomography revealed a giant left adrenal tumor with a diameter of 12 cm. The patient then underwent robotic-assisted adrenal tumor resection. Histopathological assessment indicated adrenocortical oncocytic neoplasm with uncertain malignant potential. After 4 years of follow-up, no recurrence of symptoms was noted, and this patient delivered a healthy infant on her due date in October 2021. This article reviews the clinical features, diagnosis, and treatment of ACONs and highlights the importance of differential diagnosis for hyperandrogenism in women.

Ratiometric Raman nanotags enable intraoperative detection of metastatic sentinel lymph node.

Sentinel lymph node (SLN) imaging and biopsy has been advocated as an important technique to evaluate the metastatic status of regional lymph nodes and determine subsequent surgical procedure for many cancers, yet there is no reliable means to provide accurate and rapid diagnosis of metastatic SLN during surgery. Here we develop a new approach, named "Ratiometric Raman dual-nanotag strategy", that using folic acid functionalized targeted and nontargeted gap-enhanced Raman tags (FA-GERTs and Nt-GERTs) to detect metastatic SLN based on Raman imaging combined with classical least square data processing methods. By using this strategy, with built-in self-calibration for signal correction, rather than absolute intensity-dependent signal readout, we realize the visualization and prompt intraoperative diagnosis of metastatic SLN with a high accuracy of 87.5 % when the cut-off value of ratio (FA-GERTs/Nt-GERTs) set at 1.255. This approach may outperform the existing histopathological assessment in diagnosing SLN metastasis and is promising for guiding surgical procedure in the future.

Fundamentals of Optical Imaging.

Optical imaging, which possesses noninvasive and high-resolution features for biomedical imaging, has been used to study various biological samples, from in vitro cells, ex vivo tissue, to in vivo imaging of living organism. Furthermore, optical imaging also covers a very wide scope of spatial scale, from submicron sized organelles to macro-scale live biological samples, enabling it a powerful tool for biomedical studies. Before introducing these superior optical imaging methods to researchers, first of all, it is necessary to present the basic concept of light-matter interactions such as absorption, scattering, and fluorescence, which can be used as the imaging contrast and also affect the imaging quality. And then the working mechanism of various imaging modalities including fluorescence microscopy, confocal microscopy, multiphoton microscopy, super-resolution microscopy, optical coherence tomography (OCT), diffuse optical tomography (DOT), etc. will be presented. Meanwhile, the main features and typical bioimaging applications of these optical imaging technologies are discussed. Finally, the perspective of future optical imaging methods is presented. The aim of this chapter is to introduce the background and principle of optical imaging for grasping the mechanism of advanced optical imaging modalities introduced in the following chapters.

Nucleolus-Targeted Photodynamic Anticancer Therapy Using Renal-Clearable Carbon Dots.

Photodynamic therapy (PDT), which utilizes light excited photosensitizers (PSs) to generate reactive oxygen species (ROS) and consequently ablate cancer cells or diseased tissue, has attracted a great deal of attention in the last decades due to its unique advantages. In order to further enhance PDT effect, PSs are functionalized to target specific sub-cellular organelles, but most PSs cannot target nucleolus, which is demonstrated as a more efficient and ideal site for cancer treatment. Here, an effective carbon dots (C-dots) photosensitizer with intrinsic nucleolus-targeting capability, for the first time, is synthesized, characterized, and employed for in vitro and in vivo image-guided photodynamic anticancer therapy with enhanced treatment performance at a low dose of PS and light irradiation. The C-dots possess high ROS generation efficiency and fluorescence quantum yield, excellent in vitro and in vivo biocompatibility, and rapid renal clearance, endowing it with a great potential for future translational research.

Flexible porphyrin doped polymer optical fibers for rapid and remote detection of trace DNT vapor.

With the rapid growth of anti-terrorist activities worldwide, it becomes an emerging requirement to rapidly and accurately detect hidden explosive threats. However, the safety issue during the explosive material detection, e.g. unexpected explosion, is still an insurmountable challenge. In this study, we design and mass-produce a novel kind of flexible 5,10,15,20-tetrakis(4-aminophenyl)porphyrin doped polymer optical fiber (PPOF) for rapid and accurate detection of trace 2,4-dinitrotoluene (DNT) vapor based on the DNT induced florescence quenching mechanism. The influence of doping concentration, bending, and temperature on the sensing performance is investigated. PPOF shows immunity to bending, enabling it to work in a harsh environment. It is experimentally demonstrated that the limit of detection and response time of the proposed PPOF could reach around 120 ppb and 3 minutes, respectively, which make it much better than other techniques. Owning to its inherent advantages including low-cost, remote-control capability, and compatibility with optical communication networking, PPOF can be constructed the quasi-distributed sensing networking of explosive matters in the future, providing a new strategy for anti-terrorism.

Intraoperative Raman-Guided Chemo-Photothermal Synergistic Therapy of Advanced Disseminated Ovarian Cancers.

Abdominal miliary spread and metastasis is one of the most aggressive features in advanced ovarian cancer patients. The current standard treatment of advanced ovarian cancer is cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC). However, most patients cannot receive optimal CRS outcomes due to the extreme difficulty of completely excising all microtumors during operation. Though HIPEC can improve prognosis, treatment is untargeted and may damage healthy organs and cause complications. New strategies for precise detection and complete elimination of disseminated microtumors without side effects are therefore highly desirable. Here, cisplatin-loaded gap-enhanced Raman tags (C-GERTs) are designed specifically for the intraoperative detection and elimination of unresectable disseminated advanced ovarian tumors. With unique and strong Raman signals, good biocompatibility, decent plasmonic photothermal conversion, and good drug loading capacity, C-GERTs enable detection and specific elimination of microtumors with a minimum diameter of 1 mm via chemo-photothermal synergistic therapy, causing minimal side effects and significantly prolonging survival in mice. The results demonstrate that C-GERTs-based chemo-photothermal synergistic therapy can effectively control the spread of disseminated tumors in mice and has potential as a safe and powerful method for treatment of advanced ovarian cancers, to improve survival and life quality of patients.

Gap-enhanced Raman tags for high-contrast sentinel lymph node imaging.

The sentinel lymph node (SLN) biopsy is gaining in popularity as a procedure to investigate the lymphatic metastasis of malignant tumors. The commonly used techniques to identify the SLNs in clinical practice are blue dyes-guided visualization, radioisotope-based detection and near-infrared fluorescence imaging. However, all these methods have not been found to perfectly fit the clinical criteria with issues such as short retention time in SLN, poor spatial resolution, autofluorescence, low photostability and high cost. In this study, we have reported a new type of nanoprobes, named, gap-enhanced Raman tags (GERTs) for the SLN Raman imaging. With the advantageous features including unique "fingerprint" Raman signal, strong Raman enhancement, high photostability, good biocompatibility and extra-long retention time, we have demonstrated that GERTs are greatly favorable for high-contrast and deep SLN Raman imaging, which meanwhile reveals the dynamic migration behavior of the probes entering the SLN. In addition, a quantitative volumetric Raman imaging (qVRI) data-processing method is employed to acquire a high-resolution 3-dimensional (3D) margin of SLN as well as the content variation of GERTs in the SLN. Moreover, SLN detection could be realized via a cost-effective commercial portable Raman scanner. Therefore, GERTs hold the great potential to be translated in clinical application for accurate and intraoperative location of the SLN.