Special Issue "Neurogenetics in Neurology".

With the rapid developments in molecular genetics and genomics, this Special Issue collates works outlining ultra-modern scientific research [...].

Hereditary spastic paraplegias proteome: common pathways and pathogenetic mechanisms.

INTRODUCTION: Hereditary spastic paraplegias (HSPs) are a group of inherited neurodegenerative disorders characterized by progressive spasticity and weakness of the lower limbs. These conditions are caused by lesions in the neuronal pyramidal tract and exhibit clinical and genetic variability. Ongoing research focuses on understanding the underlying mechanisms of HSP onset, which ultimately lead to neuronal degeneration. Key molecular mechanisms involved include axonal transport, cytoskeleton dynamics, myelination abnormalities, membrane trafficking, organelle morphogenesis, ER homeostasis, mitochondrial dysfunction, and autophagy deregulation. AREAS COVERED: This review aims to provide an overview of the shared pathogenetic mechanisms in various forms of HSPs. By examining disease-causing gene products and their associated functional pathways, this understanding could lead to the discovery of new therapeutic targets and the development of treatments to modify the progression of the disease. EXPERT OPINION: Investigating gene functionality is crucial for identifying shared pathogenetic pathways underlying different HSP subtypes. Categorizing protein function and identifying pathways aids in finding biomarkers, predicting early onset, and guiding treatment for a better quality of life. Targeting shared mechanisms enables efficient and cost-effective therapies. Prospects involve identifying new disease-causing genes, refining molecular processes, and implementing findings in diagnosis, key for advancing HSP understanding and developing effective treatments.

Comparison between X-ray-hysterosalpingography and 3 Tesla magnetic resonance-hysterosalpingography in the assessment of the tubal patency in the cause of female infertility.

OBJECTIVES: XR-hysterosalpingography currently represents the gold standard for tubal pathology evaluation. Magnetic resonance-HSG is an innovative technique. With our study, we aim to comprehend if and how MR-HSG, compared to traditional XR-HSG, could give us this additional information in the diagnostic/therapeutic process. MATERIALS AND METHODS: This study included 19 patients between 30 and 42 years old (average age 37.7) affected by infertility. Patients underwent contextually both XR-HSG and MR-HSG, using a single catheterization. The dynamic MR-HSG exam consisted a MR sequence during contrast administration through the cervical catheter. RESULTS: Both XR-HSG and MR-HSG documented that 15 of the 19 patients had bilateral tubal patency, while four patients had monolateral tubal patency. However, MR-HSG allowed us to diagnose additional findings: Two active endometriosis foci in adnexal localization and a condition of adenomyosis A unicornuate uterus malformation A submucous uterine myoma near the tubal ostium A decrease of the ovarian reserve in a patient So MR-HSG could potentially detect in 10/19 (52%) women the cause of their infertility, compared to 4/19 (21%) detected with XR-HSG and about 30% of women would have resulted as false negatives if we only used XR-HSG. Finally, with a questionnaire, we demonstrated that MR-HSG is less painful than XR-HSG. CONCLUSIONS: These data thus confirm that XR-HSG and MR-HSG present the same diagnostic of assessing tubal patency. We also demonstrated that MR-HSG is able to detect further collateral findings that could likewise be a possible therapeutic target and it could possibly become the new gold standard in female infertility diagnostics.

SIRM-SIN-AIOM: appropriateness criteria for evaluation and prevention of renal damage in the patient undergoing contrast medium examinations-consensus statements from Italian College of Radiology (SIRM), Italian College of Nephrology (SIN) and Italian Association of Medical Oncology (AIOM).

The increasing number of examinations and interventional radiological procedures that require the administration of contrast medium (CM) in patients at risk for advanced age and/or comorbidities highlights the problem of CM-induced renal toxicity. A multidisciplinary group consisting of specialists of different disciplines-radiologists, nephrologists and oncologists, members of the respective Italian Scientific Societies-agreed to draw up this position paper, to assist clinicians increasingly facing the challenges posed by CM-related renal dysfunction in their daily clinical practice.The major risk factor for acute renal failure following CM administration (post-CM AKI) is the preexistence of renal failure, particularly when associated with diabetes, heart failure or cancer.In accordance with the recent guidelines ESUR, the present document reaffirms the importance of renal risk assessment through the evaluation of the renal function (eGFR) measured on serum creatinine and defines the renal risk cutoff when the eGFR is < 30 ml/min/1.73 m2 for procedures with intravenous (i.v.) or intra-arterial (i.a.) administration of CM with renal contact at the second passage (i.e., after CM dilution with the passage into the pulmonary circulation).The cutoff of renal risk is considered an eGFR < 45 ml/min/1.73 m2 in patients undergoing i.a. administration with first-pass renal contact (CM injected directly into the renal arteries or in the arterial district upstream of the renal circulation) or in particularly unstable patients such as those admitted to the ICU.Intravenous hydration using either saline or Na bicarbonate solution before and after CM administration represents the most effective preventive measure in patients at risk of post-CM AKI. In the case of urgency, the infusion of 1.4% sodium bicarbonate pre- and post-CM may be more appropriate than the administration of saline.In cancer patients undergoing computed tomography, pre- and post-CM hydration should be performed when the eGFR is < 30 ml/min/1.73 m2 and it is also advisable to maintain a 5 to 7 days interval with respect to the administration of cisplatin and to wait 14 days before administering zoledronic acid.In patients with more severe renal risk (i.e., with eGFR < 20 ml/min/1.73 m2), particularly if undergoing cardiological interventional procedures, the prevention of post-CM AKI should be implemented through an internal protocol shared between the specialists who treat the patient.In magnetic resonance imaging (MRI) using gadolinium CM, there is a lower risk of AKI than with iodinated CM, particularly if doses < 0.1 mmol/kg body weight are used and in patients with eGFR > 30 ml/min/1.73 m2. Dialysis after MRI is indicated only in patients already undergoing chronic dialysis treatment to reduce the potential risk of systemic nephrogenic fibrosis.

Hereditary Spastic Paraplegia: An Update.

Hereditary spastic paraplegia (HSP) is a rare neurodegenerative disorder with the predominant clinical manifestation of spasticity in the lower extremities. HSP is categorised based on inheritance, the phenotypic characters, and the mode of molecular pathophysiology, with frequent degeneration in the axon of cervical and thoracic spinal cord's lateral region, comprising the corticospinal routes. The prevalence ranges from 0.1 to 9.6 subjects per 100,000 reported around the globe. Though modern medical interventions help recognize and manage the disorder, the symptomatic measures remain below satisfaction. The present review assimilates the available data on HSP and lists down the chromosomes involved in its pathophysiology and the mutations observed in the respective genes on the chromosomes. It also sheds light on the treatment available along with the oral/intrathecal medications, physical therapies, and surgical interventions. Finally, we have discussed the related diagnostic techniques as well as the linked pharmacogenomics studies under future perspectives.

The Puzzle of Hereditary Spastic Paraplegia: From Epidemiology to Treatment.

Inherited neurodegenerative pathology characterized by lower muscle tone and increasing spasticity in the lower limbs is termed hereditary spastic paraplegia (HSP). HSP is associated with changes in about 80 genes and their products involved in various biochemical pathways, such as lipid droplet formation, endoplasmic reticulum shaping, axon transport, endosome trafficking, and mitochondrial function. With the inheritance patterns of autosomal dominant, autosomal recessive, X-linked recessive, and mitochondrial inheritance, HSP is prevalent around the globe at a rate of 1-5 cases in every 100,000 individuals. Recent technology and medical interventions somewhat aid in recognizing and managing the malaise. However, HSP still lacks an appropriate and adequate therapeutic approach. Current therapies are based on the clinical manifestations observed in the patients, for example, smoothing the relaxant spastic muscle and physiotherapies. The limited clinical trial studies contribute to the absence of specific pharmaceuticals for HSPs. Our current work briefly explains the causative genes, epidemiology, underlying mechanism, and the management approach undertaken to date. We have also mentioned the latest approved drugs to summarise the available knowledge on therapeutic strategies for HSP.

Tips for TIPS: A combined percutaneous and transjugular approach for intrahepatic portosystemic shunt placement after liver transplant.

A 39-year-old female, liver transplanted for Autosomic Dominant Polycystic Kidney Disease (ADPKD) developed refractory ascites early after surgery, with frequent need of large-volume paracentesis. This was associated with severe sarcopenia and kidney impairment. Liver biopsy showed a sinusoidal congestion with a significant enlargement of hepatic portal veins. This picture suggested the diagnosis of vascular obstructions. Due to an unfavorable passage through the piggy-back surgical anastomosis and the angle between the hepatic veins and the portal branches, a conventional placement of a transjugular portosystemic shunt (TIPS) was not feasible. An alternative approach was pursued with success, using a combined percutaneous-transjugular approach and achieving a complete recovery of ascites, sarcopenia and renal function.

Shear wave elastography and microvascular ultrasound in response evaluation to calcipotriol+betamethasone foam in plaque psoriasis.

Psoriasis (PsO) is a chronic skin disease. This study aims to evaluate clinical and subclinical response to calcipotriol+betamethasone foam, in patients with PsO, comparing, for the first time, data from microvascular ultrasound (MicroV) and shear wave elastography (SWE) with Psoriasis Area and Severity Index (PASI). METHODS: Between November 2018 and April 2019 in Tor Vergata Hospital (Roma, Italy), we enrolled 26 patients with PsO who were ageds 20-75 years, with PASI score ≥4, candidated for calcipotriol+betamethasone foam treatment. They underwent MicroV and SWE evaluation at baseline (T0) and after 4 weeks of treatment (T4). Clinical follow-up was carried on at T4, T8 and T12. Student's t-test (p values<0.05 statistically significant) was used to compare SWE and PASI values. RESULTS: At T0, SWE stiffness values of target plaques (61.5% on elbows, 23% knees, 7.7% sacrum,7.7% legs) were significantly higher than values under healthy skin. At T4, all patients showed a significant reduction of PASI; MicroV showed reduction in vascularisation of responsive plaques in 85% of cases, only in 15%, the vascularisation degree remained stable; and SWE values of target plaques were significantly lower compared with T0. Only in 7.7%, there was a relapse at T12. CONCLUSIONS: Calcipotriol+betamethasone foam is a very effective topical treatment in a short-medium term follow-up in patients with PsO. MicroV and SWE evaluate response to treatment (in term of plaque vascularisation and stiffness), so they could represent promising early indicators of therapeutic response and help the physician to establish a better clinical-therapeutic management of patients with PsO.

Provision of Italian diagnostic reference levels for diagnostic and interventional radiology.

OBJECTIVES: The diagnostic reference level (DRL) is a useful tool for the optimisation of medical exposures. Thus, a Working Party coordinated by the Italian National Institute of Health and the National Workers Compensation Authority has been formed to provide Italian DRLs, for both diagnostic and interventional procedures, to be used as appropriate for the implementation of the 2013/59 European Directive into the national regulation. MATERIALS AND METHODS: The multidisciplinary Working Party was formed by professionals involved in diagnostic and interventional radiology medical exposures and started from a critical revision of both the literature and the results of previous Italian surveys. The procedures were divided into five sections for adult (projection radiography, mammography, diagnostic fluoroscopy, CT and interventional radiology) and two sections for paediatric patients (projection radiography and CT). The provided DRL values have been identified for "normal" adult patients and for age-classes of paediatric patients. RESULTS: Some of the DRL values provided by the Working Party are reported in this study as an example, divided by adult/paediatric patients, radiological technique and examination: specifically, DRLs for new radiological practices and new dose quantities as DRLs metric were introduced. The median value (rather than the mean) for each procedure, derived from a sample of patients, has to be compared with the corresponding DRL value, and dosimetric data related to a minimum number of patients should be collected for each examination. CONCLUSIONS: The approach to the definition and use of DRLs through guidelines of national Authorities in collaboration with scientific Associations should simplify the periodical updating and could be useful for keeping the optimisation of medical exposures faithful to the development of radiological practice.

Are there pulmonary sequelae in patients recovering from COVID-19?

It has been recently hypothesized that infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may lead to fibrotic sequelae in patients recovering from coronavirus disease 2019 (COVID-19). In this observational study, hospitalized patients with COVID-19 had a HRCT of the chest performed to detect the extension of fibrotic abnormalities via Hounsfield Units (HU). At follow-up, the lung density significantly improved in both lungs and in each lobe of all patients, being in the normal range (- 950 to - 700 HU). This study provides preliminary evidence that hospitalized patients with mild-to-moderate forms of COVID-19 are not at risk of developing pulmonary fibrosis.

Degradable starch microspheres transarterial chemoembolization (DSMs-TACE) in patients with unresectable hepatocellular carcinoma (HCC): long-term results from a single-center 137-patient cohort prospective study.

PURPOSE: To evaluate safety and efficacy of degradable starch microspheres (DSMs) TACE in a large clinical cohort of patients with unresectable HCC. MATERIALS AND METHODS: This is a single-center consecutive patients cohort study. The study was approved by local institutional ethics committee. Written informed consent was obtained. From December 2013 to March 2018, 137 cirrhotic patients with unresectable HCC were enrolled. For DSMs-TACE, a mixture of 4 mL of DSMs, 6 mL of non-ionic contrast and doxorubicin at a dose of 50 mg/m2 were used. Primary end point was long-term outcome, in terms of time to progression (TTP) and overall survival (OS). Secondary endpoints were: safety, liver toxicity, 1-month percentage of tumor necrosis according to the modified RECIST criteria. RESULTS: Two hundred and sixty-seven DSMs-TACE were performed in 137 HCC patients (33 patients in BCLC stage A, 84 patients in BCLC stage B, and 20 in stage C). Patients had a mean nodule number of 3.5 ± 1.2 (SD). Major complications were observed in 6.8% of cases. Post-embolization syndrome was common (101 patients 73.7%). According to mRecist criteria, a high objective response rate was obtained even after just one treatment (84.3% of patients showed complete response or partial response). The median TTP and OS after DSMs-TACE were 12 months and 36 months, respectively. OS at 6 months, 1 year, 2 and 3 years was 98%, 81.3%, 57.9%, 34.9%, respectively. CONCLUSION: DSMs-TACE is a safe and effective therapy for patients with HCC, allowing to obtain a good rate of OS with excellent local tumor control.

SPG11-related parkinsonism: Clinical profile, molecular imaging and l-dopa response.

BACKGROUND: Molecular imaging has proven to be a powerful tool to elucidate degenerated paths in a wide variety of neurological diseases and has not been systematically studied in hereditary spastic paraplegias. OBJECTIVES: To investigate dopaminergic degeneration in a cohort of 22 patients with hereditary spastic paraplegia attributed to SPG11 mutations and evaluate treatment response to l-dopa. METHODS: Patients and controls underwent single-photon emission computed tomography imaging utilizing 99m Tc-TRODAT-1 tracer. A single-blind trial with 600 mg of l-dopa was performed comparing UPDRS scores. RESULTS: Reduced dopamine transporter density was universal among patients. Nigral degeneration was symmetrical and correlated with disease duration and motor and cognitive handicap. No statistically significant benefit could be demonstrated with l-dopa intake during the trial. CONCLUSION: Disruption of presynaptic dopaminergic pathways is a widespread phenomenon in patients with SPG11 mutations, even in the absence of parkinsonism. Unresponsiveness to treatment could be related to postsynaptic damage that needs to be further investigated.

Impact of remnant vital tissue after locoregional treatment and liver transplant in hepatocellular cancer patients, a multicentre cohort study.

The role of pathological findings after locoregional treatments as predictors of hepatocellular cancer recurrence after liver transplantation has been poorly addressed. The aim of the study was to identify the role of remnant vital tissue (RVT) of the target lesion in predicting hepatocellular cancer recurrence. Two hundred and seventy-six patients firstly undergoing locoregional treatment and then transplanted between January 2010 and December 2015 in four European Transplant Centres (i.e. Rome Tor Vergata, Birmingham, Brussels and Ancona) were enrolled in the study to investigate the role of pathological response at upfront locoregional treatment. At multivariable Cox regression analysis, RVT ≥2 cm was a strong independent risk factor for post-LT recurrence (HR = 5.6; P < 0.0001). Five-year disease-free survival rates were 60.8%, 80.9% and 95.0% in patients presenting a RVT ≥2 cm vs. 0.1-1.9 vs. no RVT, respectively. When only Milan Criteria-IN patients were analysed, similar results were reported, with 5-year disease-free survival rates of 58.1%, 79.0% and 94.0% in patients presenting a RVT ≥2 cm vs. 0.1-1.9 vs. no RVT, respectively. RVT is an important determinant of tumour recurrence after liver transplantation performed for hepatocellular cancer. Its discriminative power looks to be evident also in a Milan-IN setting, suggesting to more liberally use locoregional treatments also in these patients.

ALS5/SPG11/KIAA1840 mutations cause autosomal recessive axonal Charcot-Marie-Tooth disease.

Charcot-Marie-Tooth disease is a group of hereditary peripheral neuropathies that share clinical characteristics of progressive distal muscle weakness and atrophy, foot deformities, distal sensory loss, as well as diminished tendon reflexes. Hundreds of causative DNA changes have been found, but much of the genetic basis of the disease is still unexplained. Mutations in the ALS5/SPG11/KIAA1840 gene are a frequent cause of autosomal recessive hereditary spastic paraplegia with thin corpus callosum and peripheral axonal neuropathy, and account for ∼ 40% of autosomal recessive juvenile amyotrophic lateral sclerosis. The overlap of axonal Charcot-Marie-Tooth disease with both diseases, as well as the common autosomal recessive inheritance pattern of thin corpus callosum and axonal Charcot-Marie-Tooth disease in three related patients, prompted us to analyse the ALS5/SPG11/KIAA1840 gene in affected individuals with autosomal recessive axonal Charcot-Marie-Tooth disease. We investigated 28 unrelated families with autosomal recessive axonal Charcot-Marie-Tooth disease defined by clinical, electrophysiological, as well as pathological evaluation. Besides, we screened for all the known genes related to axonal autosomal recessive Charcot-Marie-Tooth disease (CMT2A2/HMSN2A2/MFN2, CMT2B1/LMNA, CMT2B2/MED25, CMT2B5/NEFL, ARCMT2F/dHMN2B/HSPB1, CMT2K/GDAP1, CMT2P/LRSAM1, CMT2R/TRIM2, CMT2S/IGHMBP2, CMT2T/HSJ1, CMTRID/COX6A1, ARAN-NM/HINT and GAN/GAN), for the genes related to autosomal recessive hereditary spastic paraplegia with thin corpus callosum and axonal peripheral neuropathy (SPG7/PGN, SPG15/ZFYVE26, SPG21/ACP33, SPG35/FA2H, SPG46/GBA2, SPG55/C12orf65 and SPG56/CYP2U1), as well as for the causative gene of peripheral neuropathy with or without agenesis of the corpus callosum (SLC12A6). Mitochondrial disorders related to Charcot-Marie-Tooth disease type 2 were also excluded by sequencing POLG and TYMP genes. An additional locus for autosomal recessive Charcot-Marie-Tooth disease type 2H on chromosome 8q13-21.1 was excluded by linkage analysis. Pedigrees originated in Italy, Brazil, Canada, England, Iran, and Japan. Interestingly, we identified 15 ALS5/SPG11/KIAA1840 mutations in 12 families (two sequence variants were never reported before, p.Gln198* and p.Pro2212fs*5). No large deletions/duplications were detected in these patients. The novel mutations seemed to be pathogenic since they co-segregated with the disease in all pedigrees and were absent in 300 unrelated controls. Furthermore, in silico analysis predicted their pathogenic effect. Our results indicate that ALS5/SPG11/KIAA1840 is the causative gene of a wide spectrum of clinical features, including autosomal recessive axonal Charcot-Marie-Tooth disease.

COLLABORADI: a rule-based diagnostic imaging prescription system to help the general practitioner to choose the most appropriate radiological imaging procedures.

Significant advances in medical imaging have been made in the past decades, enabling physicians to reach high precision in diagnosing patients' diseases by means of sophisticated imaging tools. However, the use of sophisticated tools is limited by the high costs and, in some cases, by the utilization of ionizing radiation, which have both great impact on the economy of a nation and on citizens' health, respectively. Guidelines have been published among countries to provide physicians with structured rules to be followed to suggest the correct imaging technique, suiting better the diagnostic question and avoiding inappropriate imaging requests. The COLLABORADI is a research project that addressed the phenomenon of inappropriate imaging prescriptions in Sicily (Italy) and proposed the design and implementation of a clinical decision support system to help physicians to set up the most appropriate diagnostic route for their patients. The aim of this paper is to describe the characteristics of the COLLABORADI software and its potential impact in diminishing inappropriate imaging.

A homozygous mutation of VWA3B causes cerebellar ataxia with intellectual disability.

BACKGROUND: Hereditary cerebellar ataxia constitutes a heterogeneous group of neurodegenerative disorders, occasionally accompanied by other neurological features. Genetic defects remain to be elucidated in approximately 40% of hereditary cerebellar ataxia cases in Japan. We attempted to identify the gene responsible for autosomal recessive cerebellar ataxia with intellectual disability. METHODS: The present study involved three patients in a consanguineous Japanese family. Neurological examination and gene analyses were performed in all family members. We performed genome-wide linkage analysis including single nucleotide polymorphism arrays, copy-number variation analysis and whole exome sequencing. To clarify the functional alteration resulting from the identified mutation, we performed cell viability assay of cultured cells expressing mutant protein. RESULTS: One homozygous region shared among the three patients on chromosomes 2p16.1-2q12.3 was identified. Using whole exome sequencing, six homozygous variants in genes in the region were detected. Only one variant, VWA3B c.A1865C, results in a change of a highly conserved amino acid (p.K622T) and was not present in control samples. VWA3B encodes a von Willebrand Factor A Domain-Containing Protein 3B with ubiquitous expression, including the cerebellum. The viability of cultured cells expressing the specific K622T mutation was proved to decrease through the activation of apoptotic pathway. CONCLUSIONS: Mutated VWA3B was found to be likely associated with cerebellar degeneration with intellectual disability. Although a rare cause of cerebellar degeneration, these findings indicate a critical role for VWA3B in the apoptosis pathway in neuronal tissues.

Role of MRI with hepatospecific contrast agent in the identification and characterization of focal liver lesions: pathological correlation in explanted livers.

AIM: To assess the diagnostic performance of magnetic resonance imaging (MRI) with gadoxetic acid in the identification of hepatocellular carcinoma (HCC) nodules by comparison with histological findings. METHODS: In a cohort of patients suffering from cirrhosis of various etiologies (chronic hepatitis C virus (HCV) or hepatitis B virus (HBV), alcohol abuse, cryptogenic forms), we selected 17 patients affected by HCC who were eligible for liver transplantation on the basis of a computed-tomography (CT) total-body examination. Such patients also underwent an MRI examination under basal conditions, and with four dynamic phases, as well as a hepatobiliary phase acquired after at least 20 min and recognized by the excretion of contrast agent into the bile duct, following intravenous administration of 0.05 mol/kg of gadoxetic acid (gadoxetate disodium, Primovist(®); Bayer, Osaka, Japan). The MRI images were then evaluated in a double-blinded experimental setup by two radiologists experienced in imaging of the liver. The diagnosis of HCC was made in the presence of nodular lesions that showed typical or atypical enhancement patterns. The liver was subsequently explanted (on average 47.4 days after MRI evaluation), dissected into 1-cm samples, and histologically evaluated according to the classification of Edmondson-Steiner. RESULTS: At the histopathological examination, 46 nodules were identified, on average 2.7 nodules for each patient. Of these, 37 were hepatocellular carcinomas, 3 were characterized by histologically unrecognizable complete necrosis, and 6 showed high-grade dysplasia. MRI with hepatospecific contrast medium showed inter-observer average values of sensitivity, specificity, and diagnostic accuracy of 94.6, 90, and 93.6 %, respectively. In one case, a nodule was not identified by MRI with gadoxetic acid, even in the hepatospecific phase (false negative (FN)). This result could be implicated to the long time interval between the analysis and the explant (88 days). In another case, there was an overdiagnosis of a HCC with a typical nodular pattern (false positive (FP)), but which most likely should have been attributed to a previous echinococcus cyst. MRI analysis, in combination with the study of the hepatobiliary phase, also showed a greater sensitivity, the same specificity, and a greater diagnostic accuracy compared to MRI evaluated only in the dynamic phases (with an average percentage between the two operators, respectively, of 75.7, 90, and 78 %). CONCLUSIONS: MRI with gadoxetic acid shows a diagnostic accuracy superior to contrast-enhanced MRI, allowing for the diagnosis of additional lesions, and it could be considered as an imaging method to carry out a more appropriate management of waiting lists for liver transplants.

Nitric oxide depletion alters hematopoietic stem cell commitment toward immunogenic dendritic cells.

BACKGROUND: NO* is a key molecule involved in the regulation of cell survival, proliferation and differentiation in many cell types. In this study we investigated the contribution of NO* during the differentiation of human peripheral blood hemopoietic stem cells (CD34+HSCs) toward immunogenic dendritic cells (i-DCs). METHODS: We depleted autocrine NO* production, using NG-monomethyl-L-arginine monoacetate (L-NMMA) and paracrine NO', using oxy-hemoglobin (HbO2) as a NO* scavenger during in vitro differentiation of CD34+HSCs to i-DCs. We monitored the NO* level, cell proliferation, phenotype and differentiation potential. RESULTS: We found that the depletion of paracrine or autocrine NO* correlated with (I) an active proliferation state at the end of differentiation, when control cells were not proliferating; (II) a significant reduction in the expression levels of differentiative markers (CD1a and HLA-DR) with a parallel high expression of the CD34 marker (III) with a retrieved clonogenic ability compared to control cells. CONCLUSIONS: On the whole, our data indicate that the depletion of NO* during the commitment stage blocks CD34+HSC differentiation into i-DCs and maintains an undifferentiated, highly proliferating cell population, indicating/revealing a novel role for NO* in the commitment of CD34+HSCs into i-DCs. GENERAL SIGNIFICANCE: The essential finding of the present study is that NO*, produced in HSCs by NOS enzymes, may act as autocrine and paracrine effectors regulating the in vitro differentiation process of CD34+-HSCs toward i-DCs.

Factors affecting intrapatient liver and mediastinal blood pool ¹8F-FDG standardized uptake value changes during ABVD chemotherapy in Hodgkin's lymphoma.

PURPOSE: The aim of our study was to assess the intrapatient variability of 2-deoxy-2-((18)F)-fluoro-D-glucose ((18)F-FDG) uptake in the liver and in the mediastinum among patients with Hodgkin's lymphoma (HL) treated with doxorubicin (Adriamycin), bleomycin, vinblastine and dacarbazine (ABVD) chemotherapy (CHT). METHODS: The study included 68 patients (30 men, 38 women; mean age 32 ± 11 years) with biopsy-proven HL. According to Ann Arbor criteria, 6 were stage I, 34 were stage II, 12 were stage 3 and 16 were stage 4. All of them underwent a baseline (PET0) and an interim (PET2) (18)F-FDG whole-body positron emission tomography (PET)/CT. All patients were treated after PET0 with two ABVD cycles for 2 months that ended 15 ± 5 days prior to the PET2 examination. All patients were further evaluated 15 ± 6 days after four additional ABVD cycles (PET6). None of the patients presented a serum glucose level higher than 107 mg/dl. The mean and maximum standardized uptake values (SUV) of the liver and mediastinum were calculated using the same standard protocol for PET0, PET2 and PET6, respectively. Data were examined by means of the Wilcoxon matched pairs test and linear regression analysis. RESULTS: The main results of our study were an increased liver SUVmean in PET2 (1.76 ± 0.35) as compared with that of PET0 (1.57 ± 0.31; p < 0.0001) and PET6 (1.69 ± 0.28; p = 0.0407). The same results were obtained when considering liver SUVmax in PET2 (3.13 ± 0.67) as compared with that of PET0 (2.82 ± 0.64; p < 0.0001) and PET6 (2.96 ± 0.52; p = 0.0105). No significant differences were obtained when comparing mediastinum SUVmean and SUVmax in PET0, PET2 and PET6 (p > 0.05). Another finding is a relationship in PET0 between liver SUVmean and SUVmax with the stage, which was lower in those patients with advanced disease (r (2) = 0.1456 and p = 0.0013 for SUVmean and r (2) = 0.1277 and p = 0.0028 for SUVmax). CONCLUSION: The results of our study suggest that liver (18)F-FDG uptake is variable in patients with HL during the CHT treatment and the disease course and should be considered carefully when used to define the response to therapy in the interim PET in HL.