Small Biopsy and Cytology of Pulmonary Neuroendocrine Neoplasms: Brief Overview of Classification, Immunohistochemistry, Molecular Profiles, and World Health Organization Updates.

Pulmonary neuroendocrine neoplasms comprise ~20% of all lung tumors. Typical carcinoid, atypical carcinoid, small cell carcinoma, and large cell neuroendocrine carcinoma represent the 4 major distinct subtypes recognized on resections. This review provides a brief overview of the cytomorphologic features and the 2021 World Health Organization classification of these tumor types on small biopsy and cytology specimens. Also discussed are the role of immunohistochemistry in the diagnosis and molecular signatures of pulmonary neuroendocrine tumors.

Alkali Metal Adducts of an Iron(0) Complex and Their Synergistic FLP-Type Activation of Aliphatic C-X Bonds.

We report the formation and full characterization of weak adducts between Li+ and Na+ cations and a neutral iron(0) complex, [Fe(CO)3(PMe3)2] (1), supported by weakly coordinating [BArF20] anions, [1·M][BArF20] (M = Li, Na). The adducts are found to synergistically activate aliphatic C-X bonds (X = F, Cl, Br, I, OMs, OTf), leading to the formation of iron(II) organyl compounds of the type [FeR(CO)3(PMe3)2][BArF20], of which several were isolated and fully characterized. Stoichiometric reactions with the resulting iron(II) organyl compounds show that this system can be utilized for homocoupling and cross-coupling reactions and the formation of new C-E bonds (E = C, H, O, N, S). Further, we utilize [1·M][BArF20] as a catalyst in a simple hydrodehalogenation reaction under mild conditions to showcase its potential use in catalytic reactions. Finally, the mechanism of activation is probed using DFT and kinetic experiments that reveal that the alkali metal and iron(0) center cooperate to cleave C-X via a mechanism closely related to intramolecular FLP activation.

Access to and Reactivity of Fe0 , Fe-I , FeI , and FeII PCcarbene P Pincer Complexes.

Despite their promising metal-ligand cooperative reactivity, PCcarbene P pincer ligands are rarely reported for first-row transition-metal centres. Using a dehydration methodology, we report access to an Fe0 PCcarbene P pincer complex (1) that proceeds via an isolated α-hydroxylalkyl hydrido complex (3). Reversible carbonyl migration to the carbene position in 1 is found to allow coordination chemistry and E-H bond addition (E=H, B, Cl) across the iron-carbene linkage, representing a unique mechanism for metal-ligand cooperativity. The PCcarbene P pincer ligand is also found to stabilize formal FeII , FeI , and Fe-I oxidation states, as demonstrated with synthesis and characterization of the complexes [11-X][BArF 20 ] (X=Br, I), 12, and K[13]. Compound K[13] is found to be highly reactive, and abstracts hydrogen from a range of aliphatic C-H sources. Computational analysis by DFT suggests that the formal FeI and Fe-I complexes contain significant carbene radical character. The ability of the PCcarbene P ligand scaffold to partake in metal-ligand cooperativity and to support a range of iron oxidation states renders it as potentially useful in many catalytic applications.

Aggregation-Induced Emission Probe for Specific Turn-On Quantification of Soluble Transferrin Receptor: An Important Disease Marker for Iron Deficiency Anemia and Kidney Diseases.

Transferrin receptor (TfR) is overexpressed on the surface of many cancer cells due to its vital roles in iron circulation and cellular respiration. Soluble transferrin receptor (sTfR), a truncated extracellular form of TfR in serum, is an important marker of iron deficiency anemia (IDA) and bone marrow failure in cancer patients. More recently, sTfR level in urine has been related to a specific kidney disease of Henoch-Schönlein purpura nephritis (HSPN). Despite the universal significance of sTfR, there is still a lack of a simple and sensitive method for the quantification of sTfR. Furthermore, it is desirable to have a probe that can detect both TfR and sTfR for further comparison study. In this work, we developed a water-soluble AIE-peptide conjugate with aggregation-induced emission (AIE) characteristics. Taking advantage of the negligible emission from molecularly dissolved tetraphenylethene (TPE), probe TPE-2T7 was used for the light-up detection of sTfR. The probe itself is nonemissive in aqueous solution, but it turns on its fluorescence upon interaction with sTfR to yield a detection limit of 0.27 µg/mL, which is much lower than the sTfR level in IDA patients. Furthermore, a proof-of-concept experiment validates the potential of the probe for diagnosis of HSPN by urine test.

Synthesis, characterisation and reactivity of copper(I) amide complexes and studies on their role in the modified Ullmann amination reaction.

A series of copper(I) alkylamide complexes have been synthesised; copper(I) dicyclohexylamide (1), copper(I) 2,2,6,6-tetramethylpiperidide (2), copper(I) pyrrolidide (3), copper(I) piperidide (4), and copper(I) benzylamide (5). Their solid-state structures and structures in [D6 ]benzene solution are characterised, with the aggregation state in solution determined by a combination of DOSY NMR spectroscopy and DFT calculations. Complexes 1, 2 and 4 are shown to exist as tetramers in the solid state by X-ray crystallography. In [D6 ]benzene solution, complexes 1, 2 and 5 were found by using (1) H DOSY NMR to exist in rapid equilibrium between aggregates with average aggregation numbers of 2.5, 2.4 and 3.3, respectively, at 0.05 M concentration. Conversely, distinct trimeric, tetrameric and pentameric forms of 3 and 4 were distinguishable by one-dimensional (1) H and (1) H DOSY NMR spectroscopy. Complexes 3-5 are found to react stoichiometrically with iodobenzene, in the presence or absence of 1,10-phenanthroline as an ancillary ligand, to give arylamine products indicative of their role as potential intermediates in the modified Ullmann reaction. The role of phenanthroline has also been explored both in the stoichiometric reaction and in the catalytic Ullmann protocol.

Multimetallic complexes and functionalized gold nanoparticles based on a combination of d- and f-elements.

The new DO3A-derived dithiocarbamate ligand, DO3A-(t)Bu-CS2K, is formed by treatment of the ammonium salt [DO3A-(t)Bu]HBr with K2CO3 and carbon disulfide. DO3A-(t)Bu-CS2K reacts with the ruthenium complexes cis-[RuCl2(dppm)2] and [Ru(CH═CHC6H4Me-4)Cl(CO)(BTD)(PPh3)2] (BTD = 2,1,3-benzothiadiazole) to yield [Ru(S2C-DO3A-(t)Bu)(dppm)2](+) and [Ru(CH═CHC6H4Me-4)(S2C-DO3A-(t)Bu)(CO)(PPh3)2], respectively. Similarly, the group 10 metal complexes [Pd(C,N-C6H4CH2NMe2)Cl]2 and [PtCl2(PPh3)2] form the dithiocarbamate compounds, [Pd(C,N-C6H4CH2NMe2)(S2C-DO3A-(t)Bu)] and [Pt(S2C-DO3A-(t)Bu)(PPh3)2](+), under the same conditions. The linear gold complexes [Au(S2C-DO3A-(t)Bu)(PR3)] are formed by reaction of [AuCl(PR3)] (R = Ph, Cy) with DO3A-(t)Bu-CS2K. However, on reaction with [AuCl(tht)] (tht = tetrahydrothiophene), the homoleptic digold complex [Au(S2C-DO3A-(t)Bu)]2 is formed. Further homoleptic examples, [M(S2C-DO3A-(t)Bu)2] (M = Ni, Cu) and [Co(S2C-DO3A-(t)Bu)3], are formed from treatment of NiCl2·6H2O, Cu(OAc)2, or Co(OAc)2, respectively, with DO3A-(t)Bu-CS2K. The molecular structure of [Ni(S2C-DO3A-(t)Bu)2] was determined crystallographically. The tert-butyl ester protecting groups of [M(S2C-DO3A-(t)Bu)2] (M = Ni, Cu) and [Co(S2C-DO3A-(t)Bu)3] are cleaved by trifluoroacetic acid to afford the carboxylic acid products, [M(S2C-DO3A)2] (M = Ni, Cu) and [Co(S2C-DO3A)3]. Complexation with Gd(III) salts yields trimetallic [M(S2C-DO3A-Gd)2] (M = Ni, Cu) and tetrametallic [Co(S2C-DO3A-Gd)3], with r(1) values of 11.5 (Co) and 11.0 (Cu) mM(-1) s(-1) per Gd center. DO3A-(t)Bu-CS2K can also be used to prepare gold nanoparticles, Au@S2C-DO3A-(t)Bu, by displacement of the surface units from citrate-stabilized nanoparticles. This material can be transformed into the carboxylic acid derivative Au@S2C-DO3A by treatment with trifluoroacetic acid. Complexation with Gd(OTf)3 or GdCl3 affords Au@S2C-DO3A-Gd with an r(1) value of 4.7 mM(-1) s(-1) per chelate and 1500 mM(-1) s(-1) per object.

Cytopathology: From its humble beginnings to the birth of the cytopathology fellowship.

Cytopathology or cytology as a field has grown remarkably in the 20th and 21st centuries with recent advances shaping the way we train our future colleagues and how we currently practice. This article explores the history of cytopathology tracing back as early as the 18th century with focus on the birth of the cytopathology fellowship in the United States.

Case of lung fine needle aspiration showing mucinous cells and extracellular mucin.

Mucinous neoplasm with extracellular mucin can be challenging to interpret on fine needle aspiration and core biopsies. Determining the biologic origin of the mucin/mucinous cells, that is, benign/incidental versus neoplasm, invasive versus in situ, and primary versus metastatic tumors, requires a thorough multidisciplinary evaluation. The work up of these lesions includes morphologic analysis with ancillary immunohistochemical and/or molecular studies and correlation with clinical and imaging studies. This review outlines a practical approach to the diagnosis of mucinous lesions in the lung with comprehensive review of literature.

Interobserver Variability in HER-2 Immunostaining Interpretation of Metastatic HER2 Low Breast Cancers in Cytology Specimens.

BACKGROUND: Approximately, 55% of breast carcinomas are reported to be HER-2 low breast carcinomas. Trastuzumab-Deruxtecan is a new FDA-approved targeted therapy for HER-2 low metastatic breast carcinomas, making it essential that all efforts are made to identify these tumors in specimens submitted for pathologic examination. Cytology specimens are often the first and only modality of this assessment due to the ease of specimen procurement. This study aimed to determine the variability in HER-2 immunostaining interpretation among observers using cytologic specimens from metastatic sites. DESIGN: A pathology database search was made to identify metastatic breast carcinoma reported in cytology specimens. A manual search was then done to identify cases of HER-2 low category, H&E cell block and HER-2 neu immunostain slides were retrieved for a total of 50 cases. Reviewer #1 and #2 independently interpreted HER-2 immunostain of all 50 cases. Only discordant cases were sent for reviewer-3 interpretation. All three were blinded by the metastatic site, and original HER-2 interpretation. RESULTS: Of 50 cases, 11 cases (22%) were reported as concordant scores between reviewer #1 and reviewer #2 but had a discordant original IHC report. Additionally, 4 cases (8%) had discordant reporting of HER2 IHC stain between reviewer #1 and reviewer #2 making a total of 15 cases (30%) with overall discordant results. CONCLUSION: This study highlights the interobserver variability of HER-2 immunostain interpretation for HER-2 low category of breast carcinomas. We recommend the need for more robust laboratory techniques including molecular for uniform identification of these unique targetable metastatic breast carcinoma groups.

Powassan meningoencephalitis, New York, New York, USA.

Disease caused by Powassan virus (POWV), a tick-borne flavivirus, ranges from asymptomatic to severe neurologic compromise and death. Two cases of POWV meningoencephalitis in New York, USA, highlight diagnostic techniques, neurologic outcomes, and the effect of POWV on communities to which it is endemic.

Diagnostic implication of extracellular mucin in pancreatic/biliary brushing and stent cytology.

BACKGROUND: Pancreatic and/or biliary (PB) brushing is commonly used to rule out malignant strictures. Many studies have attempted to characterize cytomorphologic characteristics of brushing and stent cytology. However, scant literature exists on the diagnostic implication (DI) of thick extracellular mucin (ECM) indicative of neoplasm in these samples. This study was aimed at reviewing the DI of thick ECM in PB brushing and stent cytology. METHODS: A retrospective search of consecutive cytologic samples of PB brushings/stents with corresponding surgical pathology or relevant clinical information over a 1-year period was performed. Blinded review of the slides was performed by two cytopathologists. The slides were assessed for the presence, quantity, and quality of ECM. The results were analyzed for statistical significance with the Fisher exact and χ2 tests. RESULTS: One hundred ten cases were identified from 63 patients. Twenty-two cases (20%) were PB brushings only without a prior stent. The remaining 88 cases (80%) had a preexisting stent for symptomatic obstruction. Fourteen of 22 cases (63%) without prior stents and 67 of 88 poststented cases (76%) were nonneoplastic (NN) upon follow-up. ECM was present more frequently in neoplastic cases than in NN cases (p = .03). Among NN cases (n = 87), poststented samples showed more evidence of ECM than prestented samples (15% vs. 45%, p = .045). Identical thick ECM was observed in NN poststent and main-duct intraductal papillary neoplasm samples. CONCLUSIONS: Although ECM was frequently seen in neoplastic cases, NN cases showed increased evidence of thick ECM among poststented samples. Thick ECM may be common in stent cytology, regardless of the underlying biologic process.

Fine-needle aspiration biopsy of growing teratoma syndrome as a diagnostic pitfall of metastatic adenocarcinoma.

Growing teratoma syndrome (GTS) is a rare clinical entity that can occur in patients with a history of treatment for germ cell tumors (GCTs) and normalized serum tumor markers. Owing to the assortment of tissue types found in teratomas that may exhibit atypical features, distinguishing GTS from metastatic cancer in extragonadal masses can be challenging. Fine-needle aspiration biopsy (FNAB) can be useful for the rapid diagnosis of metastatic masses and has been effective in distinguishing GCTs from one another. However, discrepancies in cytologic and histologic diagnoses have been reported in the evaluation of GCTs by FNAB. The potential incomplete sampling of metastatic teratomas in GTS by FNAB along with features of cellular atypia commonly found in teratomas can lead to a misdiagnosis of metastatic carcinoma and drastically affect treatment. Correlation of cytologic, histologic, clinical, and radiographic findings are essential in evaluating metastatic masses in patients with a history of GCT. We report a case of a 46-year-old man with GTS originally diagnosed on FNAB as metastatic adenocarcinoma compatible with a colorectal primary tumor.

MicroRNA miR-133b is essential for functional recovery after spinal cord injury in adult zebrafish.

MicroRNAs (miRNAs) play important roles during development and also in adult organisms by regulating the expression of multiple target genes. Here, we studied the function of miR-133b during zebrafish spinal cord regeneration and show upregulation of miR-133b expression in regenerating neurons of the brainstem after transection of the spinal cord. miR-133b has been shown to promote tissue regeneration in other tissue, but its ability to do so in the nervous system has yet to be tested. Inhibition of miR-133b expression by antisense morpholino (MO) application resulted in impaired locomotor recovery and reduced regeneration of axons from neurons in the nucleus of the medial longitudinal fascicle, superior reticular formation and intermediate reticular formation. miR-133b targets the small GTPase RhoA, which is an inhibitor of axonal growth, as well as other neurite outgrowth-related molecules. Our results indicate that miR-133b is an important determinant in spinal cord regeneration of adult zebrafish through reduction in RhoA protein levels by direct interaction with its mRNA. While RhoA has been studied as a therapeutic target in spinal cord injury, this is the first demonstration of endogenous regulation of RhoA by a microRNA that is required for spinal cord regeneration in zebrafish. The ability of miR-133b to suppress molecules that inhibit axon regrowth may underlie the capacity for adult zebrafish to recover locomotor function after spinal cord injury.

Efficient Killing of Multidrug-Resistant Internalized Bacteria by AIEgens In Vivo.

Bacteria infected cells acting as "Trojan horses" not only protect bacteria from antibiotic therapies and immune clearance, but also increase the dissemination of pathogens from the initial sites of infection. Antibiotics are hard and insufficient to treat such hidden internalized bacteria, especially multidrug-resistant (MDR) bacteria. Herein, aggregation-induced emission luminogens (AIEgens) such as N,N-diphenyl-4-(7-(pyridin-4-yl) benzo [c] [1,2,5] thiadiazol-4-yl) aniline functionalized with 1-bromoethane (TBP-1) and (3-bromopropyl) trimethylammonium bromide (TBP-2) (TBPs) show potent broad-spectrum bactericidal activity against both extracellular and internalized Gram-positive pathogens. TBPs trigger reactive oxygen species (ROS)-mediated membrane damage to kill bacteria, regardless of light irradiation. TBPs effectively kill bacteria without the development of resistance. Additionally, such AIEgens activate mitochondria dependent autophagy to eliminate internalized bacteria in host cells. Compared to the routinely used vancomycin in clinic, TBPs demonstrate comparable efficacy against methicillin-resistant Staphylococcus aureus (MRSA) in vivo. The studies suggest that AIEgens are promising new agents for the treatment of MDR bacteria associated infections.

Pain and dyskinesia in Parkinson's disease may share common pathophysiological mechanisms - An fMRI study.

BACKGROUND: Parkinson's disease (PD) patients develop levodopa induced dyskinesia with disease progression from sensitization of central pathways. Pain pathways are also impacted with suggestions dyskinetic patients may process pain differently. OBJECTIVE: Establish if centrally sensitized nociceptive pathways are altered and dopaminergically driven in dyskinetic patients. METHODS: Clinical characteristics, affect, pain thresholds and sensitivity to pressure stimulation in the ON and OFF medication states as well as distribution of pain related activation of cortical regions on BOLD fMRI were assessed and compared between groups of patients suffering from dyskinesia and not. RESULTS: Dyskinetic PD participants experienced increased pressure pain sensitivity. This was associated with increased pressure induced pain>innocuous BOLD activity in areas associated with encoding pain intensity, pain spatial orientation, descending pain mediation, sensorimotor integration, and motor control. Levodopa reduced pressure pain ratings and improved negative affect, though did not impact BOLD activity differently between the groups. CONCLUSION: Dyskinetic PD patients experience increased pain sensitivity and centrally sensitized nociceptive pathways resembling levodopa induced sensitization though this is not directly influenced by dopamine.

Adamantinoma-like Ewing Sarcoma of the thyroid gland: Cytomorphologic, phenotypic and molecular features.

Adamantinoma-like Ewing Sarcoma (ALES) is a rare subtype of Ewing sarcoma family of tumors (EFTs) which are defined by their EWSR1 gene rearrangements. We present a case of a 15-year old female with a swelling in her anterior neck of 4 months duration which had recently begun to rapidly grow in size. Fine needle aspiration showed a small blue round cell tumor with immunoreactivity for cytokeratin, CD99 and FLI1. Material for molecular testing was available on the resection specimen. Demonstration of t(11;22) (EWS-FLI1) was helpful in establishing the diagnosis.

Pulmonary small cell carcinoma: Review, common and uncommon differentials, genomics and management.

Lung cancer is the leading cause of cancer-related death worldwide. It is divided into sub-categories based upon morphology, immunostaining pattern, biology, molecular profile, and/or treatment options. Up until the early 2000s when driver mutations with targeted therapies were identified in a subset of adenocarcinomas, the most critical distinction of lung carcinomas was driven by differences in treatment between small cell carcinoma (SCC) and nonsmall cell lung carcinoma (NSCLC). The distinction between SCC and NSCLC remains critical in the 21st century for management, especially for advanced stage cancer. In the vast majority of cases, morphological features are sufficient to separate SCC from other types of lung cancers. In some instances, however, cytomorphological features and immunohistochemical overlap with other tumors, limited sample availability, and/or crush artifact pose diagnostic challenges. The aim of this review is to highlight salient features of SCC and ancillary studies to distinguish it from common and uncommon potential mimickers, as well as provide updates in genomics and management.

Update on risk stratification in the Papanicolaou Society of Cytopathology System for Reporting Pancreaticobiliary Cytology categories: 3-Year, prospective, single-institution experience.

BACKGROUND: Risk stratification is a critical element for the successful implementation of cytopathology reporting systems. To the authors' knowledge, there are limited prior studies regarding risk stratification for The Papanicolaou Society of Cytopathology System for Reporting Pancreaticobiliary Cytology (PSCPC). In the current study, the authors reported on a single-institution experience on 3-year prospective PSCPC regarding risk of malignancy (ROM) and the overall risk of malignancy (OROM). METHODS: A computerized search was performed from August 2014 to December 2017 for all pancreatic fine-needle aspiration (FNA) samples. Pathology from surgical resections and biopsies and relevant radiologic and clinical follow-up data were collected. The ROM and the OROM were calculated. The OROM was based on the total number of FNA samples in each category. RESULTS: A total of 1017 pancreatic FNA cases were identified, with surgical and/or clinical follow-up data available for 548 cases. The cytopathologic diagnoses included 242 nondiagnostic (category I), 162 benign (category II), 142 atypical (category III), 20 neoplastic-benign (category IV: benign), 133 neoplastic-other (category IV: other), 28 suspicious (category V), and 290 malignant (category VI) cases. A total of 364 malignancies were documented in 11 cases, 4 cases, 36 cases, 0 cases, 36 cases, 21 cases, and 255 cases, respectively, from categories I, II, III, IV: benign, IV:other, V, and VI. The ROM was 25%, 17.4%, 41.8%, 0%, 34.3% (95.2%), 95.5%, and 99.6%, respectively, and the OROM was 4.5%, 2.5%, 25.3%, 0%, 27.1% (83.3%), 75%, and 87.9%, respectively, for categories I, II, III, IV: benign, IV: other (with high-grade dysplasia), V, and VI. CONCLUSIONS: The true ROM for PSCPC is likely between the ROM and OROM for the benign and indeterminate categories. In the neoplastic-other category (category IV: other), identifying high-grade dysplasia is important for its association with malignancy and a higher ROM.

Lung cancer cytology and small biopsy specimens: diagnosis, predictive biomarker testing, acquisition, triage, and management.

In the 21st century, there has been a dramatic shift in the management of advanced-stage lung carcinoma, and this has coincided with an increasing use of minimally invasive tissue acquisition methods. Both have had significant downstream effects on cytology and small biopsy specimens. Current treatments require morphologic, immunohistochemical, and/or genotypical subtyping of non-small cell lung carcinoma. To meet these objectives, standardized classification of cytology and small specimen diagnoses, immunohistochemical algorithms, and predictive biomarker testing guidelines have been developed. This review provides an overview of current classification, biomarker testing, methods of small specimen acquisition and triage, clinical management strategies, and emerging technologies.

A lipophilic AIEgen for lipid droplet imaging and evaluation of the efficacy of HIF-1 targeting drugs.

Hypoxia-inducible factor 1 (HIF-1) is a transcription factor that mediates the cellular response to hypoxia. The upregulation of HIF-1 expression in hypoxic cells can induce the accumulation of lipid droplets (LDs), and the LD levels can in turn reflect the expression level of HIF-1. Herein, we report a LD-specific luminogen with aggregation-induced emission characteristics (AIEgen), and have explored its potential applications in the evaluation of the inhibitory efficacy of HIF-1 targeting drugs. Compared to Nile red, this AIEgen shows a larger Stokes shift, better photostability, a more sensitive response to changes in dye concentration and a broader quantitative range. We found that the AIEgen can be used for semi-quantifying LD levels in cancer cells under hypoxic conditions, and for evaluating the inhibitory efficacy of HIF-1 targeting drugs. This work provides a simple and cost-effective strategy for screening HIF-1-targeted drugs, which may also be an alternative for evaluating the drug efficacy of other LD-related diseases.