Exploring divergent kinematics in autism across social and non-social vitality forms.

Vitality Forms (VFs) constitute the dynamic essence of human actions, providing insights into how individuals engage in activities. The ability to perceive and express VFs during interpersonal interactions is pivotal for understanding others' intentions, behaviors, and fostering effective social communication. Despite their ubiquity in all actions, research exploring the role of VFs in neurodivergent conditions related to social and communicative skills, particularly in autism, remains limited. This study aims to investigate the expression of different VFs during the execution of both social and non-social actions in children with an Autism Spectrum Condition (ASC) in comparison to neurotypical children (NT). ASC children and NT children were asked to move a small bottle either towards a target point (non-social context) or moving it towards a receiver (social context) with different VFs specifically neutral, gentle, or rude. Videotaped tasks were subsequently analyzed to study kinematic parameters characterizing VFs. Our results highlighted three main findings: (1) overall, ASC children are able to tune the motor profile of their actions, effectively conveying both gentle and rude VFs; (2) distinct kinematic parameters in the execution of VFs are able to distinguish autistic children from NT children; (3) the social context significantly influences the child's ability to express positive and negative VFs in autism. Taken together, these findings provide new insights to understand how VFs contribute to the complex dynamics of social communication in neurodivergent autistic children, providing a valuable contribution for future interventions and support strategies.

Early-onset epileptic encephalopathy in a girl carrying a truncating mutation of the ARX gene: rethinking the ARX phenotype in females.

Severe early-onset epilepsy is due to a number of known causes, although a clear etiology is not identifiable in up to a third of all the cases. Pathogenic sequence variations in the ARX gene have been described almost exclusively in males, whereas heterozygous female relatives, such as mothers, sisters and even grandmothers have been largely reported as asymptomatic or mildly affected. To investigate the pathogenic role of ARX in refractory epilepsy of early onset even in females, we have screened the ARX sequence in a population of 50 female subjects affected with unexplained epileptic encephalopathy with onset in the first year of life. We report the identification of a novel truncating mutation of the coding region of the ARX gene in a girl with a structurally normal brain. Our findings confirm the role of ARX in the pathogenesis of early epilepsy and underline the importance of screening of the ARX gene in both male and female subjects with otherwise unexplained early onset epileptic encephalopathy.

A novel SACS mutation results in non-ataxic spastic paraplegia and peripheral neuropathy.

BACKGROUND AND PURPOSE: Mutations in the SACS gene are commonly associated with autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS), a complex neurodegenerative disorder characterized by progressive degeneration of the cerebellum and spinal cord tracts. The aim of this study was to identify the genetic cause of the disease in an Italian family with spastic paraplegia and peripheral neuropathy. METHODS: Affected subjects were subjected to a comprehensive neurological examination including electromyography and brain magnetic resonance imaging. Genetic studies included exclusion of known disease genes, genome-wide linkage analysis using high density single nucleotide polymorphism genotyping and candidate gene sequencing. RESULTS: Molecular analyses revealed a novel missense mutation in the SACS gene (c.11,104A>G) occurring in a homozygous state in patients and absent in 700 Italian control chromosomes. The mutation led to the amino acid substitution p.Thr3702Ala in the sacsin protein, in a possible protein-protein interaction site of UBE3A binding domain. CONCLUSION: This study broadens the genetic spectrum of SACS mutations and expands the clinical ARSACS phenotype suggesting that the SACS gene can be considered in patients with non-canonical ARSACS clinical presentations.

Unified Description of the Specific Heat of Ionic Bulk Materials Containing Nanoparticles.

The specific heat behavior in bulk nanomaterials (NMs) obtained by adding nanoparticles to pure suspending media has attracted a lot interest in recent years. Controversial results about NMs specific heat (cp) have been reported in the literature, where nanoparticles (NPs) of different sizes and materials were suspended in solid and liquid salts at different concentrations and temperatures. However, a unified picture explaining the cp enhancements and diminutions by adding NPs to pure salts is still missing. In this work, we present a general theoretical thermostatic model aimed at describing the cp behavior in two-component ionic bulk nanomaterials containing NPs. The model, designed to work in the dilute regime, divides the NM in three regions: bulk suspending medium (SM), nanoparticles, and interface regions. It includes the effects of temperature, NP size, and NP concentration (mass fraction), allowing us to calculate cp variations with respect to the pure SM and the ideal NM (where NP and SM are assumed to not interact). We then use the model to interpret results of our classical molecular dynamics simulations, which we perform in the solid and liquid phases of NMs representative of three different classes, defined according to the atomic interactions at the interface. The analysis reveals nontrivial and competing effects influencing cp, such as system-dependent atomic rearrangements at the interface, vibrations of the NP as a whole and cp variations coming from the individual NP and SM specific heats. Our study contributes to the interpretation of past controversial results and helps in designing NMs with improved thermal properties, which is highly relevant for industrial applications in thermal energy storage and renewable energy production.

Clonal analysis as a prognostic factor in multiple oral squamous cell carcinoma.

OBJECTIVES: A novel classification based on molecular methods to assess clonality defines three types of secondary oral squamous cell carcinoma (OSCC): second primary tumour (SPT) independent from the index tumour, local recurrence (LR), clonally related to the primary tumour, and second field tumour (SFT), derived from the same genetically altered mucosal field as the primary tumour. The present study applied mtDNA analysis in a group of patients experiencing a second loco-regional neoplastic manifestation. The purpose was to differentiate secondary tumours into LRs, SPTs and SFTs and evaluate the prognostic impact in terms of survival rate. MATERIAL AND METHODS: The study population comprised 23 patients who experienced a second neoplastic lesion after a surgical resection of primary OSCC. mtDNA D-loop analysis was applied in paired neoplastic lesions and in clinically and histologically normal mucosa. On the basis of mtDNA results, the second OSCC was classified as LR or SPT or SFT. Disease-free survival was defined as the duration between the appearance of the second neoplastic lesion and death of disease, or last follow-up visit. RESULTS: Seven secondary tumours were classified as LR, 12 as SFT, 4 as SPT. An altered mucosal field proved a variable significantly related to a better survival rate (p<0.05); 2/12 (16.6%) SFT events failed as compared to 5/7 LRs (71.4%) and 3/4 SPTs (75%). CONCLUSION: mtDNA analysis may be considered a useful tool to differentiate secondary tumours and might influence the choice of the most appropriate treatment in patients with multiple OSCCs.

Craniofacial morphology and airflow in children with primary snoring.

OBJECTIVE: Sleep-disordered breathing (SDB) is among the most common diseases and includes a group of pathological conditions that form a severity continuum from primary snoring (PS) to obstructive sleep apnea (OSA). SDB presents a multifactorial etiology and in children, it is often linked to adenotonsillar hypertrophy, which may lead to an alteration of the breathing pattern. Therefore, several studies hinted at the existence of a correlation between SDB and the alteration of craniofacial growth. However, these studies concentrated on the most severe forms of SDB and little evidence still exists for the mildest form of SDB, namely PS. This preliminary study investigates the association between nasal airflow, measured through rhinomanometry, and cephalometric parameters in a sample of young children with PS. PATIENTS AND METHODS: A sample of 30 children with habitual snoring aged between 5 and 8 years was selected by a SDB validated questionnaire at the Pediatric Allergology and Immunology Center of "Sapienza" University of Rome, Italy. To assess the degree of nasal obstruction, all children underwent anterior active rhinomanometry while nocturnal pulse oximetry and polysomnography were used to characterize the SDB. Cephalometric analysis was used to evaluate relevant orthodontic parameters associated to the sagittal and vertical craniofacial development and to the position of the hyoid bone. RESULTS: We found a statistically significant association between the Frankfurt mandibular angle (FMA), which measures the total facial vertical divergence, and the severity of the airflow's obstruction (p = 0.014). CONCLUSIONS: The present study supports the association between the level of nasal obstruction in children with PS and the alteration of cephalometric parameters associated with the vertical craniofacial growth, thus placing the evaluation of craniofacial parameters in the growth period in a privileged position to determine an early diagnosis of a possible insurgence of sleep disorders.

Prognostic value of serum biological markers in patients with hepatocellular carcinoma.

PURPOSE: Prognosis of patients with hepatocellular carcinoma (HCC) is assessed by using indexes based on clinical and instrumental parameters. The Cancer of the Liver Italian Program (CLIP) staging system combines the Child-Pugh classification with tumor size, portal invasion, and alpha-fetoprotein and predicts the outcome of HCC patients more precisely than the Okuda staging system. Serum levels of a number of biological variables have been found to be increased in patients with HCC and are associated with different outcomes. Our aims in this study were to test the prognostic role of the serum levels of soluble intercellular adhesion molecule-1 (sICAM-1), soluble interleukin-2 receptor (sIL-2R), interleukin 6 (IL-6), and anti-p53 and to assess whether the addition of any of the above serum markers could further improve the predictive ability of the CLIP score. EXPERIMENTAL DESIGN: Serum levels of sICAM-1, sIL-2R, IL-6, and anti-p53 were assayed in 80 patients with HCC and correlated with their outcomes. Nonparametric procedures were applied to test correlations between serum sICAM-1, sIL-2R, IL-6, anti-p53, and other prognostic factors. For survival analyses, the product-limit method, log-rank test, and Cox proportional hazards model were applied. RESULTS: Only serum levels of sIL-2R correlated with survival, which was longer for patients with lower values (< or =950 units/ml). However, with multivariate analysis sIL-2R did not confirm its predictive role when tested with the CLIP score as a covariate, with a hazard of death of 1.51 (95% confidence interval, 0.76-3.01). CONCLUSIONS: Serum levels of sICAM-1, sIL-2R, IL-6, and anti-p53 are not useful as prognostic factors for HCC in clinical practice. They do not improve the predictive ability of the CLIP score.

A genotype-phenotype correlation for GJB2 (connexin 26) deafness.

INTRODUCTION: Mutations in GJB2 are the most common cause of non-syndromic autosomal recessive hearing impairment, ranging from mild to profound. Mutation analysis of this gene is widely available as a genetic diagnostic test. OBJECTIVE: To assess a possible genotype-phenotype correlation for GJB2. DESIGN: Retrospective analysis of audiometric data from people with hearing impairment, segregating two GJB2 mutations. SUBJECTS: Two hundred and seventy seven unrelated patients with hearing impairment who were seen at the ENT departments of local and university hospitals from Italy, Belgium, Spain, and the United States, and who harboured bi-allelic GJB2 mutations. RESULTS: We found that 35delG homozygotes have significantly more hearing impairment, compared with 35delG/non-35delG compound heterozygotes. People with two non-35delG mutations have even less hearing impairment. We observed a similar gradient of hearing impairment when we categorised mutations as inactivating (that is, stop mutations or frame shifts) or non-inactivating (that is, missense mutations). We demonstrated that certain mutation combinations (including the combination of 35delG with the missense mutations L90P, V37I, or the splice-site mutation IVS1+1G>A, and the V37I/V37I genotype) are associated with significantly less hearing impairment compared with 35delG homozygous genotypes. CONCLUSIONS: This study is the first large systematic analysis indicating that the GJB2 genotype has a major impact on the degree of hearing impairment, and identifying mild genotypes. Furthermore, this study shows that it will be possible to refine this correlation and extend it to additional genotypes. These data will be useful in evaluating habilitation options for people with GJB2 related deafness.

c-erbB-3 and c-erbB-2 protein expression in node-negative breast carcinoma--an immunocytochemical study.

The type I growth factor receptor family has been found to play an important role in the control of normal growth and differentiation. Moreover, the epidermal growth factor receptor and the c-erbB-2 oncogene seem to be implicated in the pathogenesis and behaviour of several cancers, including breast cancer. c-erbB-3 is a new member of the type I receptor family for which there is currently little information available on its expression in neoplastic tissues, and on its possible prognostic significance. This study was undertaken to define the prognostic value of c-erbB-3 expression in a series of node-negative breast cancer (NNBC) patients when compared, by multivariate analysis, with expression of the c-erbB-2 protein and conventional clinicopathological features. cerbB-3 was recognised by the novel monoclonal antibody RTJ1, whereas c-erbB-2 was detected by the polyclonal antibody 21N, using immunocytochemical methods. We found that overexpression of c-erbB-3 occurs frequently in NNBC. Overall, 138 of 212 carcinomas (65%) had some degree of membrane RTJ1 staining, and 28 (13%) showed strong and generalised positivity ( ). Twenty-four per cent of carcinomas had membrane 21N staining, and 12% presented strong and generalised positivity ( ). c-erbB-3 protein expression was significantly associated only with that of c-erbB-2 (P = 0.05), whereas 21N positivity was significantly associated with small tumour size (P = 0.02) and ductal histotype (P = 0.04). No significant correlation between expression of either receptor proteins or relapse-free survival was observed after a median follow-up of 63 months. Applying multivariate analysis, only tumour size approached significance. Our results indicate that analysis of expression of c-erbB-3 and c-erbB-2 alone do not seem to be useful in identifying patients with NNBC at different risk of relapse or death.

MDMA (ecstasy) inhibition of MAO type A and type B: comparisons with fenfluramine and fluoxetine (Prozac).

3,4-Methylenedioxymethamphetamine (MDMA), a serotonin (5-HT) neurotoxin, has been shown to promote the release of serotonin (5-HT) and block its reuptake. The increased buildup of extracellular 5-HT should normally be degraded by monoamine oxidase (MAO). The effects of both enantiomers of MDMA were examined on MAO-A and monoamine oxidase-B (MAO-B) activity in rat brain homogenates. Both enantiomers competitively inhibited 5-HT catabolism by rat brain MAO-A. The Ki of MDMA for MAO-A was 22 mumol/L. A mixed type of inhibition by MDMA was observed for phenethylamine catabolism by MAO-B for both optical antipodes. Logistical analysis of concentration response curves for MDMA inhibition of MAO-A and MAO-B show an IC50 of 44 mumol/L for inhibition of MAO-A by MDMA. The IC50 value of MDMA inhibition of MAO-B was 370 mumol/L, showing a selective potency for MAO-A inhibition. The MAO inhibitory properties of fenfluramine (FEN) and fluoxetine (FLUOX) were compared to those of MDMA. The rank order potency of these drugs for MAO-A inhibition was MDMA > FLUOX > FEN, whereas for MAO-B inhibition, FLUOX > MDMA > FEN. A combination of FLUOX and MDMA at their respective IC50 did not inhibit MAO activity more than either drug alone at equivalent concentrations. These results indicate that the actions of FEN do not appear to involve MAO inhibition. MDMA (ecstasy) produced a preferential inhibition of MAO-A (IC50 = 44 mumol/L), which should increase extracellular 5-HT.(ABSTRACT TRUNCATED AT 250 WORDS)

Serotonergic sprouting into transplanted C-6 gliomas is blocked by S-100 beta antisense gene.

S-100 beta, a calcium binding protein produced by astrocytes, has been proposed to be a neuronotropic agent. In order to test the tropic effects of S-100 beta in vivo, the technique of cell transplantation was used. C6 glioma cells and C6 cells containing a S-100 beta antisense gene (C6AS) were transplanted into contralateral hippocampi. 5-HT immunoreactive, varicose fibers with a normal appearance penetrated into the glioma mass and were seen in high density around the C6 cell mass. However, 5-HT fibers with enlarged, abnormal varicosities were seen bordering C6AS tissue and were very rarely observed within the C6AS cell mass. Extracellular S-100 beta from normal C6 cells may function as a growth factor on sprouting serotonergic fibers.

p53 and c-erbB-2 protein expression in breast carcinomas. An immunohistochemical study including correlations with receptor status, proliferation markers, and clinical stage in human breast cancer.

Receptor status, proliferative activity, loss of differentiation, inactivation of tumor suppressor genes, and overexpression of oncogenes are related events that may affect the prognosis of patients with breast cancer. Ninety-seven unselected breast carcinomas were immunostained for estrogen and progesterone receptors, Ki-67 proliferation-associated antigen, p53 tumor suppressor gene product (p53), and c-erbB-2 protein. Immunohistochemical results and clinical data were compared. Altered p53 expression (regarded as indirect indication of inactivating gene alterations) was found in 25.8% of cases and was associated with a high Ki-67 labeling index, high mitotic count, and high histologic grade, with c-erbB-2 overexpression, and with negative estrogen and progesterone receptor status. p53 immunostaining could be found also in cytologic samples and correlated with p53 immunoreactivity on frozen sections of the corresponding tumors. c-erbB-2 protein overexpression was seen in 24.7% of cases and was associated with p53 altered expression and negative receptor status. Double immunohistochemical staining showed p53 and c-erbB-2 immunoreactivity in the same cells. Median and mean +/- standard deviation Ki-67 labeling index values were 15 and 16.32 +/- 10.05, respectively. Ki-67 labeling index was correlated with high mitotic count and was positively associated with histologic grade, negative progesterone receptor status, and p53 expression. Estrogen receptor status was not associated with any histologic or clinical parameters, whereas progesterone receptor status was associated with grading. The direct relation of p53 protein alterations with c-erbB-2 overexpression may be interpreted in light of the multistep model of tumor progression. Cases with altered expression of both p53 and c-erbB-2 proteins could be interpreted as having lost one inhibitory control mechanism of cell proliferation and having gained one activator of the malignant potential. However, in comparing cases with the p53 + c-erbB-2 + phenotype with cases showing positivity for only one of these gene products, no association with higher stages was seen. Detection of p53 altered expression on cytologic samples of malignant tumors may have diagnostic relevance, and p53 immunostaining may prove to be an additional diagnostic criterion in cytologic diagnosis.

Inflammatory pseudotumour of the lung. Immunohistochemical analysis on four new cases.

Inflammatory pseudotumour of the lung (I.P.) is a quite rare benign lesion, variously named by different authors. In the present report four new cases of I.P. are presented and immunohistochemically studied with a panel of antibodies. Microscopically, the most prominent histological features were the presence of interlacing bundles of elongated histiocytic-like cells, plasma cell aggregates and lymphoid follicles. Immunohistochemistry showed that plasma cells are polyclonal. The spindle cells were negative for desmin, cytokeratins, lysozyme and S-100 and immunoreactive for alpha-1-antichymotrypsin, vimentin and for smooth-muscle alpha-actin. Actin and desmin, were clearly evident in the vessels' smooth muscle layers, highlighting the angioinvasive behaviour of the lesions. Our data are in keeping with literature suggesting that I.P. is due to a mixed histiocytic-myofibroblastic-reactive proliferation and support the inflammatory nature of IP.

PCNA and Ki67 expression in breast carcinoma: correlations with clinical and biological variables.

AIMS: To investigate the expression of two cell cycle related antigens (proliferating cell nuclear antigen (PCNA) and Ki67 related antigen) in a series of breast cancers; and the possible correlations between the PCNA and Ki67 labelling indexes (PCNA-LI and Ki67-LI) and their associations with other biological and clinicopathological variables. METHODS: Ninety six ductal and 10 lobular carcinoma specimens were investigated. Samples were fixed in formalin and in Methacarnoy for localisation of PCNA. Ki67 was immunostained on frozen sections. The PCNA-LI and Ki67-LI were evaluated in relation to tumour size, mitotic count, histological grade, nodal state as well as receptor content and altered expression of the p53 gene. RESULTS: PCNA-LI did not correlate with Ki67-LI, nor was it associated with any other variable examined. A high KI67-LI (above the median value of 13.5) was associated with high grade and mitotic count, negative receptor content, and altered expression of the p53 gene, but not with other variables. CONCLUSIONS: The PCNA-LI does not seem to be a substitute for the Ki67-LI in evaluating the growth fraction in breast cancer.

Correlation of soluble interleukin-2 receptor levels with severity of chronic hepatitis C virus liver injury and development of hepatocellular cancer.

BACKGROUND: Patients with acute and chronic hepatitis B virus infection have elevated serum levels of soluble interleukin-2 receptor. This study examined patients with chronic hepatitis C virus infection to determine whether serum soluble interleukin-2 receptor levels were elevated and whether the degree of these elevations in serum levels correlated with histologic severity of hepatitis-related liver injury. METHODS: Percutaneous liver biopsies were performed on 123 patients with chronic hepatitis C virus infection. Serum levels of soluble interleukin-2 receptor in these 123 patients were measured by means of specific enzyme-linked immunoassay and were compared with levels in 174 subjects in a hepatitis-free control group. RESULTS: Soluble interleukin-2 receptor levels were significantly higher in the patients with hepatitis C than in subjects in a control group (p < 0.0001). A progressive and significant increase occurred in soluble interleukin-2 receptor levels with increasing severity of liver injury (p < 0.001). The highest levels of soluble interleukin-2 receptor occurred in patients who had hepatocellular cancer. CONCLUSIONS: Soluble interleukin-2 receptor levels correlate with the histologic severity of liver damage in patients with chronic hepatitis C virus infection and may be useful as a marker in patients at high risk of getting hepatocellular cancer.

Special features of Graves' disease in early childhood.

Graves' disease (GD) is extremely rare in children younger than 4 years of age, but if not recognized and treated it can seriously interfere with growth and development. We report three unrelated children, all females, in whom GD occurred before the age of 3. These children presented with goiter, exophthalmos, tachycardia, and hyperactivity. Moreover, one showed a severe psychomotor delay, and had previously undergone surgery due to craniosynostosis; the other two manifested a language delay. All had high thyroid hormones and thyrotropin receptor antibody (TRAb) serum levels that clearly indicated autoimmune hyperthyroidism. In all of them, the disease presumably had developed during the first or second year of life. No maternal history of GD was present in two. The third child was born to a mother affected with GD during pregnancy, but it is likely that her GD began to develop after 6 months of life. These children are being treated with methimazole, and treatment is still necessary after 32 months. TRAb levels were persistently high at follow-up. Psychological evaluation including language development at follow-up was appropriate for age in two children; the third child improved, but severe mental retardation is still evident. GD assessment in early childhood also needs to focus on psychological evaluation. Pediatricians should be aware of the possibility of permanent brain damage and craniosynostosis due to hyperthyroidism in infancy.

Short-term effects of i.v. injected murine 99MTc-F(ab')2 fragments of an anti-melanoma antibody (HMW-MAA 225.28 S) on haemato-immunological parameters in patients with melanoma.

To evaluate alterations induced by injected murine radiolabelled F(ab')2 fragments of the anti HMW-MAA MoAb 225.28S on the principal haemato-immunological parameters, 32 patients with advanced malignant melanoma were studied. No statistically significant change was found after MoAb administration, but monocytes (3 h after injection) and granular eosinophils (24 h after) were reduced and circulating immune complexes increased (3 h after). No toxic effect or adverse reaction was observed. Therefore, the controlled administration of purified MoAb fragments for diagnostic purposes seems to involve only a very low risk of immediate adverse reactions.

The soluble interleukin-2 receptor as an indicator of clinical evolution in patients with ulcerative colitis.

BACKGROUND/AIMS: The soluble interleukin-2 receptor is a useful, non-specific marker of in-vivo activated cellular immune functions. The aim of this study was to evaluate the correlation between this marker and clinical evolution of ulcerative colitis. METHODS: Serum soluble interleukin-2 receptor levels were determined, by an enzyme immune assay, in 105 patients affected by ulcerative colitis with different extent and activity of disease. Forty-six of these patients were restaged in a follow-up study, and their serum-soluble interleukin-2 receptor concentrations were measured again. RESULTS: Serum soluble interleukin-2 receptor level is higher in pan-ulcerative colitis than in left ulcerative colitis (P = 0.050) and much higher in active than in quiescent stage of disease (P = 0.029). Clinical relapse of disease is accompanied by a serum soluble interleukin-2 receptor rise (P = 0.0697), whereas clinical and histological improvement in disease is accompanied by its significant decrease (P = 0.0009). CONCLUSION: In ulcerative colitis the serum determination of soluble interleukin-2 receptor is a useful and non-invasive marker of activity, and also extension and evolution of the disease.

Bronchial carcinoids with S-100 positive sustentacular cells. A comparative study with gastrointestinal carcinoids, pheochromocytomas and paragangliomas.

Fourty-six bronchial carcinoids, twelve tumourlets and twenty areas of neuroendocrine cell dysplasia (NED) were immunohistochemically evaluated for various neuroendocrine markers, S-100 protein (S-100), myelin basic protein, intermediate filaments, actin, Leu-7 and several neurohormonal polypeptides. Eighteen of the bronchial carcinoids (39.1%) showed a biphasic cell pattern, with abundant stellate-shaped S-100 positive cells (SC). SC were not reactive for chromogranin A, myelin basic protein, cytokeratins, neurofilaments, glial fibrillary acidic protein or actin, and were only occasionally weakly positive for vimentin. SC were not detected in the tumourlets nor in the NED observed. For comparison a group of other neuroendocrine tumours (11 gastrointestinal carcinoids, 4 pheochromocytomas and 4 paragangliomas) were immunostained for S-100, chromogranin A and actin. SC similar to the ones detected in the bronchial carcinoids could be detected in appendiceal carcinoids, paragangliomas and in two out of four pheochromocytomas. Our present data are in keeping with a Schwannian/sustentacular nature of SC rather than that of a histiocytic or myoepithelial nature. We suggest that SC-rich bronchial carcinoids are biphasic tumours, which could be designed "paraganglioid" bronchial carcinoids. The relationship between SC-rich bronchial carcinoids and tumourlets/NED is a matter of further investigation: SC-rich bronchial carcinoids may either differentiate in a biphasic pattern during tumoural growth or may not be histogenetically related to tumourlets.