Circulating hematopoietic stem/progenitor cell subsets contribute to human hematopoietic homeostasis.

ABSTRACT: In physiological conditions, few circulating hematopoietic stem/progenitor cells (cHSPCs) are present in the peripheral blood, but their contribution to human hematopoiesis remain unsolved. By integrating advanced immunophenotyping, single-cell transcriptional and functional profiling, and integration site (IS) clonal tracking, we unveiled the biological properties and the transcriptional features of human cHSPC subpopulations in relationship to their bone marrow (BM) counterpart. We found that cHSPCs reduced in cell count over aging and are enriched for primitive, lymphoid, and erythroid subpopulations, showing preactivated transcriptional and functional state. Moreover, cHSPCs have low expression of multiple BM-retention molecules but maintain their homing potential after xenotransplantation. By generating a comprehensive human organ-resident HSPC data set based on single-cell RNA sequencing data, we detected organ-specific seeding properties of the distinct trafficking HSPC subpopulations. Notably, circulating multi-lymphoid progenitors are primed for seeding the thymus and actively contribute to T-cell production. Human clonal tracking data from patients receiving gene therapy (GT) also showed that cHSPCs connect distant BM niches and participate in steady-state hematopoietic production, with primitive cHSPCs having the highest recirculation capability to travel in and out of the BM. Finally, in case of hematopoietic impairment, cHSPCs composition reflects the BM-HSPC content and might represent a biomarker of the BM state for clinical and research purposes. Overall, our comprehensive work unveiled fundamental insights into the in vivo dynamics of human HSPC trafficking and its role in sustaining hematopoietic homeostasis. GT patients' clinical trials were registered at ClinicalTrials.gov (NCT01515462 and NCT03837483) and EudraCT (2009-017346-32 and 2018-003842-18).

Cardiac Amyloidosis: State-of-the-Art Review in Molecular Pathology.

Amyloidosis refers to a group of diseases caused by extracellular deposits of misfolded proteins, which alter tissue function and structure, potentially affecting any organ. The term "amyloid" was introduced in the 19th century and later associated with pathological protein deposits. Amyloid fibrils, which are insoluble and resistant to degradation, originate from soluble proteins that undergo misfolding. This process can be triggered by several factors, such as aging, elevated protein concentrations, or pathogenic variants. Amyloid deposits damage organs both by disrupting tissue architecture and through direct cytotoxic effects, leading to conditions such as heart failure. Amyloidosis can be classified into acquired or inherited forms and can be systemic or localized. Diagnosing cardiac amyloidosis is complex and often requires tissue biopsies, which are supported by Congo Red dye staining. In some cases, bisphosphonate bone scans may provide a less invasive diagnostic option. In this state-of-the-art review, we focus on the most common forms of cardiac amyloidosis, from epidemiology to therapy, emphasizing the differences in molecular mechanisms and the importance of pathological diagnosis for appropriate treatment using a multidisciplinary approach.

Circulating vitamin D level before initiating chemotherapy impacts on the time-to-outcome in metastatic colorectal cancer patients: systematic review and meta-analysis.

BACKGROUND: Vitamin D (VD) is implicated in various health conditions, including colorectal cancer (CRC). To investigate potential relationships between pre-chemotherapy VD levels and the time-to-outcome in metastatic CRC patients, we conducted a systematic review and meta-analysis. METHODS: Following the PRISMA 2020 guidelines, we performed thorough searches in PubMed/MEDLINE and Scopus/ELSEVIER databases (covering the years 2002 to 2022). Inclusion criteria mandated studies to report on individuals aged 18 years and above with histologically confirmed stage IV CRC. Additionally, studies needed to provide data on VD levels before chemotherapy, along with hazard ratios (HR) and 95% confidence intervals (CIs) for overall survival (OS) and/or progression-free survival (PFS). Five articles were identified with the aim of establishing a combined risk estimate for death and progression based on pre-chemotherapy VD levels. Heterogeneity among studies and publication bias were evaluated using Tau2, I2 statistics, and a Funnel plot. RESULTS: Although no significant heterogeneity was observed in time-to-outcome among the selected studies, variations in technical assessments and serum VD concentration measurements were noted. The pooled analysis, involving 1712 patients for OS and 1264 patients for PFS, revealed a 47% increased risk of death (HR: 1.47, 95% CI: 1.21-1.79) and a 38% increased risk of progression (HR: 1.38, 95% CI: 1.13-1.70) for patients with lower VD levels, as indicated by fixed-effects models. CONCLUSIONS: Our results emphasize the adverse effects of low VD concentration on the time-to-outcome in metastatic CRC patients. This underscores the importance of investigating VD supplementation as an innovative approach in this clinical setting to enhance patient outcomes.

Previous radiotherapy increases the efficacy of cemiplimab in the treatment of locally advanced and metastatic cutaneous squamous cell carcinoma: A retrospective analysis.

BACKGROUND: Cemiplimab, a programmed cell death-1 inhibitor approved in 2018 for patients with locally advanced or metastatic cutaneous squamous cell carcinoma (cSCC) who are ineligible for curative therapies, lacks clarity regarding the optimal patient selection despite its known efficacy. OBJECTIVE: This retrospective study aims to assess the real-world treatment patterns and outcomes in patients with cSCC at our institution. METHODS: A retrospective analysis of consecutively treated patients with cemiplimab for cSCC was conducted. Progression-free survival (PFS) and overall survival were evaluated alongside clinical-pathologic characteristics. RESULTS: Forty-five patients were included, of which 73.3% were male with a median age of 77 years. After 18 months of median follow-up median PFS and overall survival were not reached with a mean of 21.3 months ± 2.2 months and 25.3 ± 2.1 months, respectively. Univariate and multivariate analyses revealed significant correlations only between PFS and previous radiotherapy (P values: .043 and .046, respectively). LIMITATIONS: Limitations include its retrospective nature, the low number of patients analyzed, and the potential for inherent biases. CONCLUSIONS: The study reveals a significant association between prior radiotherapy and improved PFS in cemiplimab-treated cSCC, suggesting the potential for combining radiotherapy with cemiplimab. Further exploration of this combined approach is warranted.

Long-lasting effects of COVID-19 pandemic on hospitalizations and severity of bronchiolitis.

Bronchiolitis is a common cause of hospitalization in infants. The long-lasting impact of hygiene and social behavior changes during the pandemic on this disease is debated. We investigated the prevalence of hospitalized cases, clinical severity, and underlying risk factors before and during pandemic. The study was conducted in 27 hospitals in Italy and included infants hospitalized for bronchiolitis during the following four periods: July 2018-March 2019, July 2020-March 2021, July 2021-March 2022, and July 2022-March 2023. Data on demographics, neonatal gestational age, breastfeeding history, underlying chronic diseases, presence of older siblings, etiologic agents, clinical course and outcome were collected. A total of 5330 patients were included in the study. Compared to 2018-19 (n = 1618), the number of hospitalizations decreased in 2020-21 (n = 121). A gradual increase was observed in 2021-22 (n = 1577) and 2022-23 (n = 2014). A higher disease severity (need and length of O2-supplementation, need for non-invasive ventilation, hospital stay) occurred in the 2021-22 and, especially, the 2022-23 periods compared to 2018-19. This tendency persisted after adjusting for risk factors associated with bronchiolitis severity.   Conclusions: Compared to adults, COVID-19 in infants is often asymptomatic or mildly symptomatic and rarely results in hospitalization. This study indicates that the pandemic has indirectly induced an increased burden of bronchiolitis among hospitalized infants. This shift, which is not explained by the recognized risk factors, suggests the existence of higher infant vulnerability during the last two seasons. What is known: • The pandemic led to a change in epidemiology of respiratory diseases • Large data on severity of bronchiolitis and underlying risk factors before and during COVID-19 pandemic are scarce What is new: • Compared to pre-pandemic period, hospitalizations for bronchiolitis decreased in 2020-21 and gradually increased in 2021-22 and 2022-23 • Compared to pre-pandemic period, higher disease burden occurred in 2021-22 and, especially, in 2022-23. This tendency persisted after adjusting for risk factors associated with bronchiolitis severity • The interplay among viruses, preventive measures, and the infant health deserves to be further investigated.

Multidisciplinary Approach to the Diagnosis of Idiopathic Interstitial Pneumonias: Focus on the Pathologist's Key Role.

Idiopathic Interstitial Pneumonias (IIPs) are a heterogeneous group of the broader category of Interstitial Lung Diseases (ILDs), pathologically characterized by the distortion of lung parenchyma by interstitial inflammation and/or fibrosis. The American Thoracic Society (ATS)/European Respiratory Society (ERS) international multidisciplinary consensus classification of the IIPs was published in 2002 and then updated in 2013, with the authors emphasizing the need for a multidisciplinary approach to the diagnosis of IIPs. The histological evaluation of IIPs is challenging, and different types of IIPs are classically associated with specific histopathological patterns. However, morphological overlaps can be observed, and the same histopathological features can be seen in totally different clinical settings. Therefore, the pathologist's aim is to recognize the pathologic-morphologic pattern of disease in this clinical setting, and only after multi-disciplinary evaluation, if there is concordance between clinical and radiological findings, a definitive diagnosis of specific IIP can be established, allowing the optimal clinical-therapeutic management of the patient.

Prevalence, Outcome, and Prevention of Congenital Cytomegalovirus Infection in Neonates Born to Women With Preconception Immunity (CHILd Study).

BACKGROUND: Human cytomegalovirus (HCMV) is the leading infectious cause of congenital disabilities. We designed a prospective study to investigate the rate, outcome, and risk factors of congenital CMV (cCMV) infection in neonates born to immune women, and the potential need and effectiveness of hygiene recommendations in this population. METHODS: The study was composed of 2 sequential parts: an epidemiology (part 1) and a prevention (part 2) study. Performance of part 2 depended upon a cCMV rate >0.4%. Women enrolled in part 1 did not receive hygiene recommendations. Newborns were screened by HCMV DNA testing in saliva and cCMV was confirmed by urine testing. RESULTS: Saliva swabs were positive for HCMV DNA in 45/9661 newborns and cCMV was confirmed in 18 cases. The rate of cCMV was .19% (95% confidence interval [CI]: .11-.29%), and 3 out of 18 infants with cCMV had symptoms of CMV at birth. Age, nationality, occupation, and contact with children were similar between mothers of infected and noninfected newborns. Twin pregnancy (odds ratio [OR]: 7.2; 95% CI: 1.7-32.2; P = .037) and maternal medical conditions (OR: 3.9; 95% CI: 1.5-10.1; P = .003) appeared associated with cCMV. Given the rate of cCMV was lower than expected, the prevention part of the study was cancelled. CONCLUSIONS: Newborns from women with preconception immunity have a low rate of cCMV, which appears to be mostly due to reactivation of the latent virus. Therefore, serological screening in childbearing age would be pivotal to identify HCMV-seropositive women, whose newborns have a low risk of cCMV. CLINICAL TRIALS REGISTRATION: www.clinicaltrials.gov (NCT03973359).

Rectal Prolapse Pathological Features: Findings in Patients With Outlet Obstruction Treated With Stapled Transanal Rectal Resection.

BACKGROUND: Obstructed defecation syndrome is a common multifactorial disease for which treatment is based primarily on clinic presentation for the lack of reliable instrumental and anatomopathological criteria. OBJECTIVE: The study aimed to analyze the pathological findings of the resected rectal specimens after stapled transanal rectal resection in patients affected by outlet obstruction. DESIGN: Retrospective cohort study. SETTINGS: University hospital. PATIENTS: Patients who underwent rectal resection for obstructed defecation syndrome due to internal rectal prolapse were included. INTERVENTIONS: Specimens of patients with obstructed defecation syndrome were analyzed through conventional histology and morphometric image analysis and compared with those of rectal specimens excised for oncological diseases. MAIN OUTCOME MEASURES: Analysis of the anatomopathological impairments underlying rectal prolapse. RESULTS: From January 2017 to December 2020, 46 specimens from the stapled transanal rectal resection group were compared with 40 specimens from the control group. In the stapled transanal rectal resection group, conventional histology revealed 34 samples (73.9%) had moderate- to severe-grade fibrosis with moderate-grade nerve degeneration in 33 cases (71.7%). In the control group, conventional histology revealed the absence of fibrosis in 31 specimens (77.5%), whereas the absence of nerve degeneration was detected in 37 specimens (92.5%). In the stapled transanal rectal resection group, morphometric image analysis showed severe-grade fibrosis in 25 cases (54.4%) compared to only low-grade fibrosis in 11 cases (27.5%). LIMITATIONS: The small sample size and the retrospective design of the study were limitations. Moreover, there was no chance to use specimens from healthy volunteers as the control group. CONCLUSIONS: Stapled transanal rectal resection specimens showed a higher rate of fibrosis and nerve dysplasia, an important parameter that is typically not considered preoperatively and could lead patients with rectal prolapse to the best treatment approach. See Video Abstract at http://links.lww.com/DCR/B928 . CARACTERSTICAS ANATOMOPATOLGICAS EN EL PROLAPSO DE RECTO HALLAZGOS EN PACIENTES CON OBSTRUCCIN DEL TRACTO DE SALIDA TRATADOS CON RESECCIN RECTAL TRANSANAL CON GRAPAS: ANTECEDENTES:El síndrome de obstrucción del tracto de salida, es una afección multifactorial común, cuyo tratamiento está basado principalmente en la presentación clínica, ésto, debido a la falta de criterios confiables tanto instrumentales como anatomopatológicos.OBJETIVO:Analizamos los hallazgos histopatológicos de las piezas de resección rectal obtenidas por vía transanal mediante grapas, realizadas en pacientes que presentaban obstrucción del tracto de salida.DISEÑO:Este fue un estudio de cohorte retrospectivo.AJUSTE:El escenario fue un hospital universitario.PACIENTES:Aquellos sometidos a resección rectal por síndrome obstructivo del tracto de salida causada por un prolapso rectal interno.INTERVENCIONES:Los especímenes de pacientes con síndrome obstructivo defecatorio fueron analizados mediante histología convencional y análisis de imágenes morfométricas, comparados con especímenes rectales resecados por enfermedad oncológica.PRINCIPALES MEDIDAS DE RESULTADO:El resultado primario se concentró en la investigación de las deficiencias anatomopatológicas subyacentes del prolapso rectal interno.RESULTADOS:Desde enero de 2017 hasta diciembre de 2020, se compararon 46 especímenes del grupo de resección rectal transanal con grapas con 40 especímenes del grupo de control. En histología convencional, el grupo de resección rectal transanal con grapas, 34 muestras (73,9%) presentaron un grado de fibrosis moderada-severa con un grado moderado de degeneración neurógena en 33 casos (71,7%). En el grupo control, la histología convencional reveló ausencia de fibrosis en 31 especímenes (77,5 %), mientras que la ausencia de degeneración neurógena se detectó en 37 controles (92,5 %). En el grupo de resección rectal transanal con grapas, el análisis de imágenes morfométricas mostró fibrosis moderada y fibrosis severa en 19 (41,3%) y 25 (54,4%) casos, respectivamente. En el grupo control, el análisis de imágenes morfométricas mostró solo un bajo grado de fibrosis en 11 casos (27,5%). Se encontró una diferencia significativa en todos los grados de fibrosis y displasia neurógena entre los grupos en las evaluaciones de análisis de imagen morfométrica e histología convencional (p < 0,001).LIMITACIONES:El pequeño tamaño de la muestra y el diseño retrospectivo del estudio. Además, no existe la posibilidad de utilizar un grupo de control con muestras de voluntarios sanos.CONCLUSIONES:Los especímenes de resección rectal transanal con grapas mostraron una mayor tasa de fibrosis y displasia neurógena, parámetro importante que actualmente no está considerado antes de la operación y en un futuro muy cercano podría orientar a los pacientes con prolapso rectal interno hacia un mejor enfoque de tratamiento. Consulte Video Resumen en http://links.lww.com/DCR/B928 . (Traducción-Dr. Xavier Delgadillo ).

Is reflectance confocal microscopy useful in the differential diagnosis of extra facial lentigo maligna? A retrospective multicentric case-control study.

BACKGROUND: Extra facial lentigo maligna (EF-LM) arises outside the head and neck area. EF-LM presents the classic histological features of lentigo maligna. The dermoscopic aspects of EF-LM have been poorly studied. OBJECTIVE: The primary aims of our study were to analyse and describe the clinical, dermoscopic and confocal microscopy features of a series of histologically confirmed EF-LM. METHOD: We conducted a retrospective and multicentric study. From our database, we selected 48 cases of thin melanomas on photodamaged skin with histological features of EF-LM of which clinical, dermoscopic and confocal microscopy images were available, and a control group of 45 lesions, that can be subjected to differential diagnosis such as solar lentigo, lichenoid keratosis, seborrheic keratosis and melanocytic nevi, of which dermoscopic and confocal microscope images were available. RESULTS: Extra facial lentigo maligna had a higher prevalence of lentigo-like pigment patterns, angulated lines and zigzag structures. At confocal microscopy, LM-EF cases showed a higher prevalence of pagetoid spreading, round cells, dendritic cells in the epidermis, atypical cells at the dermo-epidermal junction, dendritic cells at the junction, meshwork pattern and elastosis. Our study shows that reflectance confocal microscopy (RCM) has a sensitivity of 90% and a specificity of 97% for the differential diagnosis of this type of melanoma. CONCLUSIONS: Extra facial lentigo maligna does not have the classic dermoscopic features of superficial spreading melanoma, the most observed dermoscopic criteria are angulated lines and lentigo-like pigment patterns without lentigo-like border. RCM can be a valuable imaging tool for the evaluation of all those suspicion skin lesions at dermoscopy highlighting cellular atypia suggestive for melanoma.

Primary Cutaneous B-Cell Lymphomas with Large Cell Morphology: A Practical Review.

Most primary cutaneous lymphomas consist of T-cell lymphomas or small cell lymphomas; however, the skin may also be affected by lymphomas with large cell morphology, as a primary or secondary localization. A minority of cases consist of primary cutaneous B-cell lymphomas (PCBCLs). PCBCLs are a heterogeneous group of rare neoplasms with an overlapping morphological and immunohistochemical picture of the different subtypes. Nevertheless, differential diagnosis in the setting of this group of neoplasms is mandatory to identify the correct therapy and prognosis, but it may be challenging since, due to the rarity of these neoplasms, they may not always be familiar to pathologists. Indeed, immunohistochemistry may not be enough to distinguish the different histotypes, which overlap in immunohistochemical features. Furthermore, the ever-increasing knowledge of the molecular features of systemic B-cell lymphomas, such as gene rearrangements with clinical significance, has led in recent years to further investigation into the molecular landscape of PCBCLs with large cell morphology. This work aimed to provide a practical diagnostic guide for pathologists dealing with primary cutaneous large B-cell lymphomas.

The Role of Toll-like Receptor-4 in Macrophage Imbalance in Lethal COVID-19 Lung Disease, and Its Correlation with Galectin-3.

To the current data, there have been 6,955,141 COVID-19-related deaths worldwide, reported to WHO. Toll-like receptors (TLRs) implicated in bacterial and virus sensing could be a crosstalk between activation of persistent innate-immune inflammation, and macrophage's sub-population alterations, implicated in cytokine storm, macrophage over-activation syndrome, unresolved Acute Respiratory Disease Syndrome (ARDS), and death. The aim of this study is to demonstrate the association between Toll-like-receptor-4 (TLR-4)-induced inflammation and macrophage imbalance in the lung inflammatory infiltrate of lethal COVID-19 disease. Twenty-five cases of autopsy lung tissues were studied by digital pathology-based immunohistochemistry to evaluate expression levels of TLR-4 (CD 284), pan-macrophage marker CD68 (clone KP1), sub-population marker related to alveolar macrophage Galectin-3 (GAL-3) (clone 9C4), and myeloid derived CD163 (clone MRQ-26), respectively. SARS-CoV-2 viral persistence has been evaluated by in situ hybridation (ISH) method. This study showed TLR-4 up-regulation in a subgroup of patients, increased macrophage infiltration in both Spike-1(+) and Spike-1(-) lungs (p < 0.0001), and a macrophage shift with important down-regulation of GAL-3(+) alveolar macrophages associated with Spike-1 persistence (p < 0.05), in favor of CD163(+) myeloid derived monocyte-macrophages. Data show that TLR-4 expression induces a persistent activation of the inflammation, with inefficient resolution, and pathological macrophage shift, thus explaining one of the mechanisms of lethal COVID-19.

Shortage of pathologists in Italy: survey of students and residents.

Objective: In Italy, shortage of pathologists is a problem that affects the quality of the National Health System (NHS). The cause of the shortage of pathologists in Italy must be sought in the lack of interests in the pathologist career by Medical Course Students (MCS) and in drop out of Post-Graduate Medical Schools (PGMS). We investigated reasons of both through two surveys. Methods: We developed and proposed on Facebook two surveys, one to MCSs attending last years of study and one to Pathology School Residents (PSRs). Survey for MCSs consisted of 10 questions centered on their perception about pathologist activity; survey for PSRs consisted of 8 questions and investigated the most and least appreciated aspects of Italian PGMS. Results: We obtained 500 responses from the MCSs and 51 responses from the PSRs. Our results show that lack of interest of MCS may be due to their incomplete knowledge of the pathologist's activities. On the other hand, PSR answers show that some teaching aspects should be improved. Conclusions: Our surveys showed that lack of interest of MCS in the pathology career depends on poor knowledge about the real clinical significance of pathology and PSRs believe that Italian PGMS do not meet their interest. One solution could be a renewal of teaching both in the pathology courses for MCS and in PGMS.

COVID-19: detection methods in post-mortem samples.

COVID-19 identification is routinely performed on fresh samples, such as nasopharyngeal and oropharyngeal swabs, even if, the detection of the virus in formalin-fixed paraffin-embedded (FFPE) autopsy tissues could help to underlie mechanisms of the pathogenesis that are not well understood.The gold standard for COVID-19 detection in FFPE samples remains the qRT-PCR as in swab samples, contextually other methods have been developed, including immunohistochemistry (IHC), and in situ hybridization (ISH). In this manuscript, we summarize the main data regarding the methods of COVID-19 detection in pulmonary and extra-pulmonary post-mortem samples, and especially the sensitivity and specificity of these assays will be discussed.

Current and potential immunohistochemical biomarkers for prognosis and therapeutic stratification of breast carcinoma.

The identification of biomarkers on cancer tissue samples could be obtained through several technologies. In this setting, the immunohistochemistry and in situ hybridization are accessible in most pathology laboratories. Particularly, immunohistochemistry can be used not only for diagnostic issues, but also to define prognostic classes and to define response to specific therapies. Particularly the last applications have been firstly developed in the breast cancer pathology. In addition, the development of molecular classification proposed some prognostic/predictive classes that could be easily defined by immunohistochemistry. Thus, the role of the pathologists has become increasingly important in the definition of prognosis and in the choice therapy, because the immunohistochemical biomarkers are used to guide treatment, to classify breast cancer into biologically and prognostically distinct subtypes. In this review, we will provide information on the current application of the immunohistochemical biomarkers useful in the management of breast cancer patients. Moreover, we consider the application of immunohistochemistry in the definition of the most promising biomarkers derived from molecular studies of the breast cancer, that in the future could integrate the characterization of breast cancer into clinical practice.

PD-L1 Overexpression in the Lungs of Subjects Who Died from COVID-19: Are We on the Way to Understanding the Immune System Exhaustion Induced by SARS-CoV-2?

Knowledge of the pathogenic mechanisms of severe acute respiratory syndrome-associated coronavirus 2 (SARS-CoV-2) is certainly a priority for the scientific community. Two main elements are involved in the biology of the most severe forms of coronavirus disease 2019 (COVID-19): the direct cytopathic effect of the virus against the host tissues, and a dysfunction of the immune system, characterized by the exhaustion of T lymphocytes. The exhaustion of T cells in COVID-19 is poorly understand, but some data could suggest a possible role of PD-1/PD-L1 axis. The aim of this study was to evaluate the possible role of PD-L1 expression in the pulmonary tissue in subjects affected by COVID-19. The presence of SARS-CoV-2 in the pulmonary tissue, and its exact location, was indagated by in situ hybridization; the expression of PD-L1 and CD8 in the same tissue was indagated by immunohistochemistry. Overall, PD-L1 resulted diffusely expressed in 70% of the cases, and an intense expression was observed in 43.5% of cases. Diffuse and intense presence of SARS-CoV-2 by in situ hybridization significantly correlated with an intense PD-L1 expression, and with expression of PD-L1 by pneumocytes. PD-L1 is overexpressed in the pulmonary tissue of subjects died from COVID-19, and mainly in subjects with a high viral load. These data suggest a possible role of PD-L1 in the immune system exhaustion at the basis of the severe forms of the disease.

CXCR5-CXCL13 axis markers in full-term and preterm human neonates in the first weeks of life.

Term and preterm neonates have very few circulating Tfh-like cells (cTfh), and no circulating Tfr-like cells. Neonatal cTfh are CXCR5lo PD-1lo CD45RAhi , suggestive of a naive, possibly recently activated phenotype. CXCL13 is high at birth, but decreases rapidly in the first weeks of life. Overall, signs of GC activity in human neonates are weak, even in those born prematurely or after sepsis.

SARS-CoV-2 infection and neonates: Evidence-based data after 18 months of the pandemic.

After 18 months of the COVID-19 pandemic, data concerning SARS-CoV-2 infection in pregnant women and their neonates are progressively taking the place of complete uncertainty. Here, we summarize updated evidence regarding several critical aspects of perinatal SARS-CoV-2 infection, including 1) vertical transmission of the virus in utero, which is possible but seems rare according to current epidemiological data; 2) how COVID-19 during pregnancy can shape maternal and neonatal outcomes, either directly or indirectly; 3) how recommendations regarding the management of infected dyads have been progressively modified in light of new scientific evidence; and 4) how maternal infection or vaccination can induce the passive protection of fetuses and neonates against the infection, through the transfer of specific antibodies before and after birth.

Mystery(n) Phenotypic Presentation in Europeans: Report of Three Further Novel Missense RNF213 Variants Leading to Severe Syndromic Forms of Moyamoya Angiopathy and Literature Review.

Moyamoya angiopathy (MMA) is a rare cerebral vasculopathy in some cases occurring in children. Incidence is higher in East Asia, where the heterozygous p.Arg4810Lys variant in RNF213 (Mysterin) represents the major susceptibility factor. Rare variants in RNF213 have also been found in European MMA patients with incomplete penetrance and are today a recognized susceptibility factor for other cardiovascular disorders, from extracerebral artery stenosis to hypertension. By whole exome sequencing, we identified three rare and previously unreported missense variants of RNF213 in three children with early onset of bilateral MMA, and subsequently extended clinical and radiological investigations to their carrier relatives. Substitutions all involved highly conserved residues clustered in the C-terminal region of RNF213, mainly in the E3 ligase domain. Probands showed a de novo occurring variant, p.Phe4120Leu (family A), a maternally inherited heterozygous variant, p.Ser4118Cys (family B), and a novel heterozygous variant, p.Glu4867Lys, inherited from the mother, in whom it occurred de novo (family C). Patients from families A and C experienced transient hypertransaminasemia and stenosis of extracerebral arteries. Bilateral MMA was present in the proband's carrier grandfather from family B. The proband from family C and her carrier mother both exhibited annular figurate erythema. Our data confirm that rare heterozygous variants in RNF213 cause MMA in Europeans as well as in East Asian populations, suggesting that substitutions close to positions 4118-4122 and 4867 of RNF213 could lead to a syndromic form of MMA showing elevated aminotransferases and extracerebral vascular involvement, with the possible association of peculiar skin manifestations.

Glycated ACE2 receptor in diabetes: open door for SARS-COV-2 entry in cardiomyocyte.

RATIONALE: About 50% of hospitalized coronavirus disease 2019 (COVID-19) patients with diabetes mellitus (DM) developed myocardial damage. The mechanisms of direct SARS-CoV-2 cardiomyocyte infection include viral invasion via ACE2-Spike glycoprotein-binding. In DM patients, the impact of glycation of ACE2 on cardiomyocyte invasion by SARS-CoV-2 can be of high importance. OBJECTIVE: To evaluate the presence of SARS-CoV-2 in cardiomyocytes from heart autopsy of DM cases compared to Non-DM; to investigate the role of DM in SARS-COV-2 entry in cardiomyocytes. METHODS AND RESULTS: We evaluated consecutive autopsy cases, deceased for COVID-19, from Italy between Apr 30, 2020 and Jan 18, 2021. We evaluated SARS-CoV-2 in cardiomyocytes, expression of ACE2 (total and glycosylated form), and transmembrane protease serine protease-2 (TMPRSS2) protein. In order to study the role of diabetes on cardiomyocyte alterations, independently of COVID-19, we investigated ACE2, glycosylated ACE2, and TMPRSS2 proteins in cardiomyocytes from DM and Non-DM explanted-hearts. Finally, to investigate the effects of DM on ACE2 protein modification, an in vitro glycation study of recombinant human ACE2 (hACE2) was performed to evaluate the effects on binding to SARS-CoV-2 Spike protein. The authors included cardiac tissue from 97 autopsies. DM was diagnosed in 37 patients (38%). Fourth-seven out of 97 autopsies (48%) had SARS-CoV-2 RNA in cardiomyocytes. Thirty out of 37 DM autopsy cases (81%) and 17 out of 60 Non-DM autopsy cases (28%) had SARS-CoV-2 RNA in cardiomyocytes. Total ACE2, glycosylated ACE2, and TMPRSS2 protein expressions were higher in cardiomyocytes from autopsied and explanted hearts of DM than Non-DM. In vitro exposure of monomeric hACE2 to 120 mM glucose for 12 days led to non-enzymatic glycation of four lysine residues in the neck domain affecting the protein oligomerization. CONCLUSIONS: The upregulation of ACE2 expression (total and glycosylated forms) in DM cardiomyocytes, along with non-enzymatic glycation, could increase the susceptibility to COVID-19 infection in DM patients by favouring the cellular entry of SARS-CoV2.

Synchronous intrathyroidal parathyroid carcinoma and thyroid carcinoma: case report and review of the literature.

BACKGROUND: Parathyroid carcinoma is a rare endocrine malignancy, rarer when synchronous with a non medullary well differentiated thyroid carcinoma. Parathyroid carcinoma accounts of 0.005% of all malignant tumors and it is responsible for less than 1% of primary hyperparathyroidism. The intrathyroidal localization of a parathyroid gland is not frequent with a reported prevalence of 0.2%. Carcinoma of parathyroids with intrathyroidal localization represents an even rarer finding, reported in only 16 cases described in literature. The rare constellation of synchronous parathyroid and thyroid carcinomas has prompted us to report our experience and perform literature review. CASE PRESENTATION: We herein report a case of a 63-years-old man with multinodular goiter and biochemical diagnosis of hyperparathyroidism. Total thyroidectomy with radio-guide technique using gamma probe after intraoperative sesta-MIBI administration and intraoperative PTH level was performed. The high radiation levels in the posterior thyroid lobe discovered an intrathyroidal parathyroid. Microscopic examination revealed a parathyroid main cell carcinoma at the posterior thyroidal left basal lobe, a classic papillary carcinoma at the same lobe and follicular variant of papillary carcinoma at the thyroidal right lobe. To the best of our knowledge, this is the first case documenting a synchronous multicentric non medullary thyroid carcinomas and intrathyroidal parathyroid carcinoma. CONCLUSIONS: Our experience was reported and literature review underlining challenging difficulties in diagnostic workup and surgical management was carried out.