The Luigi Sacco Hospital VAS-COG stroke care pathway: A five-year experience

Background

Psycho-cognitive consequences are a frequent cause of disability in stroke survivors but are often underdiagnosed also because of lack of services dedicated to these aspects. We started assessing systematically cognitive and behavioral functions in acute stroke patients and to follow them up. Here, we report a retrospective analysis of the organization of the Sacco VAS-COG stroke care pathway and the refinements implemented during 5 years of activity.

Methods

The protocol includes baseline collection of clinical history, general and neurologic examinations, functional, neuropsychological, and neuroimaging assessment. At follow-up, a diagnosis of cognitive decline was made based on best clinical judgment in the first period (January 2018 to May 2019, namely VAS-COG protocol 1.0) and then based on an extensive neuropsychological battery (May 2019 to January 2023, namely VASCOG protocol 2.0); psychiatric and behavioral disturbances are investigated through suitable scales.

Results

From January 2018 to December 2022, 834 patients (mean age 76±13.6 years; 46.6 % females) with acute cerebrovascular events were admitted to the stroke unit, mostly (80 %) for ischemic strokes. Pre-event cognitive impairment was not assessable in 78 patients (9.3 %) because no reliable informant was present and was reported in 327/756 (43 %) patients. During follow-up, post-stroke cognitive impairment was detected in 124/217 (57.1 %) patients in VAS-COG protocol 1.0 and in 137/201(68.2 %) patients in VAS-COG protocol 2.0, while 95/218 (43.2 %) patients were found to be depressed and patients presented on average 2.5 neuropsychiatric symptoms on Neuropsychiatric Inventory-questionnaire.

Conclusions

The VAS-COG stroke care pathway represents a model for patients and for their families.

BCL-XL inhibition induces an FGFR4-mediated rescue response in colorectal cancer

The heterogeneous therapy response observed in colorectal cancer is in part due to cancer stem cells (CSCs) that resist chemotherapeutic insults. The anti-apoptotic protein BCL-XL plays a critical role in protecting CSCs from cell death, where its inhibition with high doses of BH3 mimetics can induce apoptosis. Here, we screen a compound library for synergy with low-dose BCL-XL inhibitor A-1155463 to identify pathways that regulate sensitivity to BCL-XL inhibition and reveal that fibroblast growth factor receptor (FGFR)4 inhibition effectively sensitizes to A-1155463 both in vitro and in vivo. Mechanistically, we identify a rescue response that is activated upon BCL-XL inhibition and leads to rapid FGF2 secretion and subsequent FGFR4-mediated post-translational stabilization of MCL-1. FGFR4 inhibition prevents MCL-1 upregulation and thereby sensitizes CSCs to BCL-XL inhibition. Altogether, our findings suggest a cell transferable induction of a FGF2/FGFR4 rescue response in CRC that is induced upon BCL-XL inhibition and leads to MCL-1 upregulation.

PI3K-driven HER2 expression is a potential therapeutic target in colorectal cancer stem cells

OBJECTIVE

Cancer stem cells are responsible for tumour spreading and relapse. Human epidermal growth factor receptor 2 (HER2) expression is a negative prognostic factor in colorectal cancer (CRC) and a potential target in tumours carrying the gene amplification. Our aim was to define the expression of HER2 in colorectal cancer stem cells (CR-CSCs) and its possible role as therapeutic target in CRC resistant to anti- epidermal growth factor receptor (EGFR) therapy.

DESIGN

A collection of primary sphere cell cultures obtained from 60 CRC specimens was used to generate CR-CSC mouse avatars to preclinically validate therapeutic options. We also made use of the ChIP-seq analysis for transcriptional evaluation of HER2 activation and global RNA-seq to identify the mechanisms underlying therapy resistance.

RESULTS

Here we show that in CD44v6-positive CR-CSCs, high HER2 expression levels are associated with an activation of the phosphatidylinositol 3-kinase (PI3K)/AKT pathway, which promotes the acetylation at the regulatory elements of the Erbb2 gene. HER2 targeting in combination with phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase kinase (MEK) inhibitors induces CR-CSC death and regression of tumour xenografts, including those carrying Kras and Pik3ca mutation. Requirement for the triple targeting is due to the presence of cancer-associated fibroblasts, which release cytokines able to confer CR-CSC resistance to PI3K/AKT inhibitors. In contrast, targeting of PI3K/AKT as monotherapy is sufficient to kill liver-disseminating CR-CSCs in a model of adjuvant therapy.

CONCLUSIONS

While PI3K targeting kills liver-colonising CR-CSCs, the concomitant inhibition of PI3K, HER2 and MEK is required to induce regression of tumours resistant to anti-EGFR therapies. These data may provide a rationale for designing clinical trials in the adjuvant and metastatic setting.

CHK1 inhibitor sensitizes resistant colorectal cancer stem cells to nortopsentin

Limited therapeutic options are available for advanced colorectal cancer (CRC). Herein, we report that exposure to a neo-synthetic bis(indolyl)thiazole alkaloid analog, nortopsentin 234 (NORA234), leads to an initial reduction of proliferative and clonogenic potential of CRC sphere cells (CR-CSphCs), followed by an adaptive response selecting the CR-CSphC-resistant compartment. Cells spared by the treatment with NORA234 express high levels of CD44v6, associated with a constitutive activation of Wnt pathway. In CR-CSphC-based organoids, NORA234 causes a genotoxic stress paralleled by G2-M cell cycle arrest and activation of CHK1, driving the DNA damage repair of CR-CSphCs, regardless of the mutational background, microsatellite stability, and consensus molecular subtype. Synergistic combination of NORA234 and CHK1 (rabusertib) targeting is synthetic lethal inducing death of both CD44v6-negative and CD44v6-positive CRC stem cell fractions, aside from Wnt pathway activity. These data could provide a rational basis to develop an effective strategy for the treatment of patients with CRC.

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CR-CSCs acquire a long-term resistance to the NORA234 treatment

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Replicative and genotoxic stress induces the activation of CHK1

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Adaptive response to NORA234 is associated with high expression levels of CHK1

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NORA234 together with targeting of CHK1 leads to depletion of CR-CSC compartment

Pharmacological targeting of the novel β-catenin chromatin-associated kinase p38α in colorectal cancer stem cell tumorspheres and organoids

The prognosis of locally advanced colorectal cancer (CRC) is currently unsatisfactory. This is mainly due to drug resistance, recurrence, and subsequent metastatic dissemination, which are sustained by the cancer stem cell (CSC) population. The main driver of the CSC gene expression program is Wnt signaling, and previous reports indicate that Wnt3a can activate p38 MAPK. Besides, p38 was shown to feed into the canonical Wnt/β-catenin pathway. Here we show that patient-derived locally advanced CRC stem cells (CRC-SCs) are characterized by increased expression of p38α and are "addicted" to its kinase activity. Of note, we found that stage III CRC patients with high p38α levels display reduced disease-free and progression-free survival. Extensive molecular analysis in patient-derived CRC-SC tumorspheres and APCMin/+ mice intestinal organoids revealed that p38α acts as a β-catenin chromatin-associated kinase required for the regulation of a signaling platform involved in tumor proliferation, metastatic dissemination, and chemoresistance in these CRC model systems. In particular, the p38α kinase inhibitor ralimetinib, which has already entered clinical trials, promoted sensitization of patient-derived CRC-SCs to chemotherapeutic agents commonly used for CRC treatment and showed a synthetic lethality effect when used in combination with the MEK1 inhibitor trametinib. Taken together, these results suggest that p38α may be targeted in CSCs to devise new personalized CRC treatment strategies.

Bi-hemispheric transcranial direct current stimulation for upper-limb hemiparesis in acute stroke: a randomized, double-blind, sham-controlled trial

BACKGROUND AND PURPOSE

Neuromodulation is a promising approach to increasing motor recovery in stroke; however, to date, there is a scarcity of evidence documenting the clinical potential of transcranial direct current stimulation (tDCS) administered in the acute phase of stroke. The present study aims to examine the clinical effects of a treatment involving the application of tDCS in the acute stage post-stroke.

METHODS

This was a randomized, double-blind, sham-controlled trial. A cohort of 32 stroke patients with severe motor impairment underwent 5 days of treatment with real or sham bi-hemispheric tDCS over the motor cortex. During the treatment, tDCS was applied twice per day (two daily applications each of 15 min), starting 48 to 72 h after stroke onset.

RESULTS

We found statistically significant improvements after both real and sham tDCS treatments in primary (hand grip strength, Motricity Index) and secondary (National Institutes of Health Stroke Scale score, Barthel Index) outcomes. Patients receiving real tDCS showed a larger improvement of upper-limb muscle strength at the end of treatment phase; this advantage was no longer present after 6 months.

CONCLUSIONS

Transcranial direct current stimulation may be used to accelerate the rate of upper-limb motor recovery during the spontaneous recovery period.

DNA methylation of shelf, shore and open sea CpG positions distinguish high microsatellite instability from low or stable microsatellite status colon cancer stem cells

Aim: To investigate the genome-wide methylation of genetically characterized colorectal cancer stem cell (CR-CSC) lines. Materials & methods: Eight CR-CSC lines were isolated from primary colorectal cancer (CRC) tissues, cultured and characterized for aneuploidy, mutational status of CRC-related genes and microsatellite instability (MSI). Genome-wide DNA methylation was assessed by MethylationEPIC microarray. Results: We describe a distinctive methylation pattern that is maintained following in vivo passages in immune-compromised mice. We identified an epigenetic CR-CSC signature associated with MSI. We noticed that the preponderance of the differentially methylated positions do not reside at CpG islands, but spread to shelf and open sea regions. Conclusion: Given that CRCs with MSI-high status have a lower metastatic potential, the identification of a MSI-related methylation signature could provide new insights and possible targets into metastatic CRC.

Combined platelet-rich plasma and lipofilling treatment provides great improvement in facial skin-induced lesion regeneration for scleroderma patients

Background

The use of stem cells, including mesenchymal stem cells (MSCs), for regenerative medicine is gaining interest for the clinical benefits so far obtained in patients. This study investigates the use of adipose autologous tissue in combination with platelet-rich plasma (PRP) to improve the clinical outcome of patients affected by systemic sclerosis (SSc).

Methods

Adipose-derived mesenchymal stem cells (AD-MSCs) and PRPs were purified from healthy donors and SSc patients. The multilineage differentiation potential of AD-MSCs and their genotypic–phenotypic features were investigated. A cytokine production profile was evaluated on AD-MSCs and PRPs from both healthy subjects and SSc patients. The adipose tissue-derived cell fraction, the so-called stromal vascular fraction (SVF), was coinjected with PRP in the perioral area of SSc patients.

Results

Histopathological and phenotypical analysis of adipose tissue from SSc patients revealed a disorganization of its distinct architecture coupled with an altered cell composition. Although AD-MSCs derived from SSc patients showed high multipotency, they failed to sustain a terminally differentiated progeny. Furthermore, SVFs derived from SSc patients differed from healthy donors in their MSC-like traits coupled with an aberrant cytokine production profile. Finally, the administration of PRP in combination with autologous SVF improved buccal’s rhyme, skin elasticity and vascularization for all of the SSc patients enrolled in this study.

Conclusions

This innovative regenerative therapy could be exploited for the treatment of chronic connective tissue diseases, including SSc.

Electronic supplementary material

The online version of this article (doi:10.1186/s13287-017-0690-3) contains supplementary material, which is available to authorized users.

Localization of tyrosine hydroxylase immunoreactive neurons in the forebrain of the guppy Poecilia reticulata

The current study reports for the first time the distribution of tyrosine hydroxylase immunoreactive (TH-ir) neurons in the forebrain of the guppy Poecilia reticulata. Numerous small TH-ir neurons were observed in the olfactory bulbs, located mainly in the periphery of the bulbs. The TH-ir telencephalic neurons are localized in the ventral telencephalic area where they are grouped in three distinct nuclei (Vv,Vd and Vp) composed of a small number of cells forming a continuous strip. The largest number of forebrain TH-ir neurons was observed in the diencephalon where both small and larger neurons are present. Diencephalic TH-ir neurons are subdivided in large nuclei located in the preoptic region (nSC, nPOp and nPOm), the thalamus (nDM), the pretectal region (nPPv and nAP), the hypothalamus (nPP and nRP) and the posterior tuberculum (nPT). Many diencephalic nuclei are distributed in periventricular regions and no TH-ir cells were observed in the paraventricular organ. A comparative analysis indicates that the present observations are consistent with the general pattern of TH-ir neurons distribution reported for the forebrain of other teleosts, but with some interspecies variability present, mainly in the diencephalon. This paper also provides valuable neuroanatomical information for P. reticulata, a teleost frequently used in toxicological tests, for future studies investigating the effects of environmental pollutants on the catecholaminergic system.

Triazine compounds as antagonists at Bv8-prokineticin receptors

On the basis of a Janssen's patent, we approached a new synthesis of some 1,3,5-triazin-4,6-diones as potential non peptidic prokineticin receptor antagonists, containing the following substitutions: (N(1) and N(5) link a 4-methoxybenzyl and a 4-ethylbenzyl, respectively; C(2) can link an amino-ethyl-guanidine (reference compound 1) or an ethylendiamine (2) or an amino-ethyl-amino-2-imidazoline (3). New compounds were assessed for PKR1 and PKR2 affinity. Antagonist properties were evaluated as inhibition of 1 nM Bv8-induced intracellular Ca2+ mobilization.

Skin vasomotor reflex responses in two contrasting groups of autonomic failure

BACKGROUND & AIM

A variety of stimuli such as deep inspiration, isometric exercise and mental arithmetic, result in a transient vasoconstriction,mediated by sympathetic efferent nerves, in the skin of the fingers and toes of healthy controls (Skin Vasomotor Reflex: SkVR). Multiple system atrophy (MSA) and pure autonomic failure (PAF) provide contrasting models of autonomic failure. In MSA the lesion is central and preganglionic, whilst in PAF the lesion site is peripheral and postganglionic. We evaluated the SkVR in response to various stimuli in MSA and PAF, to determine differences in skin vasomotor involvement between these two patient groups.

METHODS

25 subjects (10 MSA, 7 PAF, 8 healthy controls) were studied. Baseline recordings of skin blood flow were obtained with a laser Doppler probe on the left index finger pulp and forearm. The subject then underwent a variety of stimuli with rest periods in between to reestablish baseline SkBF. These stimuli were: single deep inspiration (inspiratory gasp); mental arithmetic; bilateral leg elevation and cutaneous cold.

RESULTS

Healthy control subjects demonstrated marked SkVRs on the finger pulp to each of the stimuli of a magnitude similar to those seen in previous studies, but no SkVRs on the forearm. In MSA SkVRs to inspiratory gasp on the finger pulp were reduced relative to controls. In PAF SkVRs were reduced relative to controls or MSA. The magnitude of SkVR response to gasp and cutaneous cold in PAF was significantly less than in healthy controls. In addition, the magnitude of the response in PAF was significantly less than in MSA for inspiratory gasp.

CONCLUSIONS

PAF showed a decreased SkVR response to all 4 stimuli, the response being significantly less than controls (for inspiratory gasp and cutaneous cold) or MSA (cutaneous cold inspiratory gasp). The decreased responses in PAF may reflect the extensive postganglionic sympathetic denervation seen in this group. The measurement of SkVR may therefore provide a non-invasive aid to the differentiation of MSA and PAF.

Thermal perception thresholds: assessing the level of human spinal cord injury

STUDY DESIGN

Controlled, cross-sectional, observational.

OBJECTIVES

To investigate whether quantitative sensory testing (QST) is able to reveal subclinical deficits at the neurological level of lesion in subjects with chronic spinal cord injury (SCI).

SETTING

National Spinal Injuries Centre, Stoke Mandeville Hospital and Imperial College London, UK.

METHODS

QST and clinical assessments were carried out on 18 subjects with complete SCI (American Spinal Injury Association (ASIA) grade A) and 10 subjects with incomplete SCI (ASIA grades B, C or D). A total of 10 healthy subjects acted as controls.

RESULTS

At the level of lesion perceptual thresholds to monofilaments, cold pain and heat pain were similar to values in control subjects but cool and warm thresholds were significantly raised. A correlation between cool and warm thresholds was observed at the level of lesion in complete SCI and between heat and cold pain thresholds at the level of lesion in complete SCI, incomplete SCI and in control subjects. In the zone of partial preservation in complete SCI and below the level of lesion in incomplete SCI, thresholds for all modalities were all different compared to controls.

CONCLUSION

QST reveals impaired thermal sensation in dermatomes clinically defined as normal with ASIA standards. Quantitative thermal testing therefore permits a discriminating assessment of preserved sensation and subclinical deficit and has the potential to improve upon the clinical detection of natural recovery or changes in level of injury following interventions designed to repair SCI.

Heat-provoked skin vasodilatation in innervated and denervated trunk dermatomes in human spinal cord injury

STUDY DESIGN

Cross-sectional, observational, controlled study.

OBJECTIVE

High spinal cord injury (SCI) results in disruption of sympathetic vasomotor control. Vasodilatation as a response to local heating is a biphasic mechanism: the first phase (neurogenic) is mediated by the axon-reflex and is modulated by activity of sympathetic nerves. Our objective was to determine whether the response to heat provocation in trunk dermatomes may provide a measure of vasomotor sympathetic function in SCI.

SETTING

National Spinal Injuries Centre, Stoke Mandeville Hospital, Buckinghamshire, UK; Autonomic Unit, The National Hospital for Neurology and Neurosurgery, Queen Square, London, UK; Neurovascular Medicine Unit, Imperial College London at St Mary's Hospital, UK.

SUBJECTS

A total of 30 subjects were studied; 18 had chronic complete SCI (level C6-T11) and 12 were healthy controls.

METHODS

Recordings of skin blood flow (SkBF) were obtained with thermostatic laser Doppler probes placed in the upper trunk (at C4) and lower trunk (T10 or T12) dermatomes.

RESULTS

SkBF at baseline (SkBF(bas)) and SkBF at the first peak of vasodilatation (SkBF(max)) showed no significant differences between SCI and controls either in upper or lower trunk dermatomes. However, the ratio of SkBF(max)/SkBF(bas) was significantly different in lower trunk dermatomes in SCI at C6-T5 level (7.5+/-3.5 PU) compared to SCI at T6-T11 level (3.5+/-1.5 PU) (P < 0.01).

CONCLUSION

Measurement of SkBF in response to local heating may provide a safe, noninvasive method to assess integrity of sympathetic spinal pathways to the local vasculature. This may aid the classification of the SCI lesions, as the autonomic component currently is not included in the accepted American Spinal Injury Association scoring.

Blood-brain barrier-specific properties of a human adult brain endothelial cell line

Establishment of a human model of the blood-brain barrier has proven to be a difficult goal. To accomplish this, normal human brain endothelial cells were transduced by lentiviral vectors incorporating human telomerase or SV40 T antigen. Among the many stable immortalized clones obtained by sequential limiting dilution cloning of the transduced cells, one was selected for expression of normal endothelial markers, including CD31, VE cadherin, and von Willebrand factor. This cell line, termed hCMEC/D3, showed a stable normal karyotype, maintained contact-inhibited monolayers in tissue culture, exhibited robust proliferation in response to endothelial growth factors, and formed capillary tubes in matrix but no colonies in soft agar. hCMEC/D3 cells expressed telomerase and grew indefinitely without phenotypic dedifferentiation. These cells expressed chemokine receptors, up-regulated adhesion molecules in response to inflammatory cytokines, and demonstrated blood-brain barrier characteristics, including tight junctional proteins and the capacity to actively exclude drugs. hCMEC/D3 are excellent candidates for studies of blood-brain barrier function, the responses of brain endothelium to inflammatory and infectious stimuli, and the interaction of brain endothelium with lymphocytes or tumor cells. Thus, hCMEC/D3 represents the first stable, fully characterized, well-differentiated human brain endothelial cell line and should serve as a widely usable research tool.

Characterization of glial fibrillary acidic protein and astroglial architecture in the brain of a continuously growing fish, the rainbow trout

Unlike mammals, some fish, including carp and trout, have a continuously growing brain. The glial architecture of teleost brain has been intensively studied in the carp and few data exist on trout brain. In this study, using immunoblotting we characterized the topographic distribution of glial fibrillary acidic protein (GFAP) in larval and adult rainbow trout brain and studied by immunohistochemistry the distribution and morphology of GFAP-immunoreactive cell systems in the rainbow trout hindbrain and spinal cord. Immunoblotting yielded a double band with an apparent molecular weight of 50-52 kDa in the spinal cord homogenate in the trout larval and adult stages. In the adult hindbrain and forebrain, our antibody cross reacted also with a second band at a higher molecular weight (90 kDa). Because the forebrain contained this band alone the two brain regions might contain two distinct isoforms. Conversely, the larval total brain homogenate contained the heavy 90 kDa band alone. Hence the heavy band might be a GFAP protein dimer or vimentin/GFAP copolymer reflecting nerve fiber growth and elongation, or the two isoforms might indicate two distinct astroglial cell types as recently proposed in the zebrafish. In sections from trout hindbrain and spinal cord the antibody detected a GFAP-immunoreactive glial fiber system observed in the raphe and in the glial septa separating the nerve tracts. These radial glia fibers thickened toward the pial surface, where they formed glial end feet. The antibody also labeled perivascular glia around blood vessels in the white matter, and the ependymoglial plexus surrounding the ventricular surface in the grey matter. Last, it labeled round astrocytes. The GFAP-immunoreactive glial systems had similar distribution patterns in the adult and larval spinal cord suggesting early differentiation.

The basilar pontine nuclei and the nucleus reticularis tegmenti pontis subserve distinct cerebrocerebellar pathways

Previous studies often considered the basilar pontine nuclei (BPN) and the nucleus reticularis tegmenti pontis (NRTP) as relays of a single cerebro-(ponto)-cerebellar pathway. Conversely, the different cortical afferences to the BPN and the NRTP, as well as the anatomical and functional features of the cerebellopetal projections from these pontine nuclei, support the different, and for some aspect, complementary arrangement of the cerebrocerebellar pathways relayed by the BPN or NRTP. Both the BPN and the NRTP are innervated from the cerebral cortex, but with regional prevalence. The NRTP is principally innervated from motor or sensori-motor areas while the BPN are principally innervated from sensory, mainly teloceptive, and associative area. Projections from sensory-motor areas were also traced to the BPN. The BPN and NRTP project to all parts of the cerebellar cortex with a similar pattern. In fact, from single areas of them projections were traced to set of sagittal stripes of the cerebellar cortex. In variance to such analogies, the projections to the cerebellar nuclei differed between those traced from the NRTP and from BPN. In fact, BPN and NRTP have private terminal areas in the cerebellar nuclei with relatively little overlaps. The BPN innervated the lateroventral part of the nucleus lateralis and the caudoventral aspect of the nucleus interpositalis posterioris. The NRTP principally innervated the mediodorsal part of the nucleus lateralis, the nucleus interpositalis anterioris, the nucleus medialis. Since the single cerebellar nuclei have their specific targets in the extracerebellar brain areas, it follows that the BPN and the NRTP, passing through their cerebellar nuclei relays, are devoted to control different brain areas and thus likely to play different functional roles. From single pontine regions (of both BPN and NRTP) projections were traced to the cerebellar cortex and to the cerebellar nuclei. In some cases these projections reached areas which are likely anatomically connected (by Purkinje axons). This pattern of the pontine projections was termed as coupled projection. In some other cases, the projections reached areas of the cerebellar cortex but not the nuclear regions innervated by them. We termed this as uncoupled projection. The existence of both coupled and uncoupled projections, open new vistas on the functional architecture of the pontocerebellar pathway. More in detail, this study showed the different quantitative and topographic distribution of the coupled and uncoupled projections visualized in the cerebellar projections from BPN and NRTP. All these evidences strongly support the anatomical and the functional differences that characterise the cerebrocerebellar pathways relayed by the BPN and the NRTP.

Skin vasodilator response to local heating in human chronic spinal cord injury

Local heating evokes an increase in skin blood flow (SkBF), which consists of an initial peak (axon-reflex mediated) followed by a brief nadir and a secondary rise to a plateau. The aim of this study was to investigate whether heat provoked vasodilatation detects sympathetic vasomotor dysfunction and completeness of injury in patients with spinal cord injury (SCI). Twelve (seven complete, and five incomplete; level C4-L4) SCI patients, and nine healthy subjects as controls were studied. Thermostatic laser Doppler probes, which heat the skin locally, were placed on the dorsum of the hand and foot. SkBF was measured by laser Doppler flowmetry at baseline and at the first peak of vasodilatation (SkBF(max)). On the hand, SkBF at baseline and SkBF(max) were similar between the three groups. On the foot, SkBF at baseline was similar between the three groups but SkBF(max) was significantly diminished in complete SCI patients compared with controls (P < 0.01). In conclusion, heat provoked axon-reflex vasodilatation was diminished in the foot, below the level of lesion, in complete SCI. This test, that evaluates localized sympathetic vasomotor dysfunction, may be a useful non-invasive technique to detect completeness of autonomic disruption after SCI.

[Rare malignant tumors of the thyroid]

The incidence of rare malignant tumors of the thyroid is about 4 cases/100,000 people and represent only 1.8% of all the thyroid cancers. When we talk about "rare" tumors, obviously, we do not refer to the most frequent cancers (papillary, follicular), or less frequent tumors (medullary, anaplastic), but to some types of thyroid tumors that have been almost always sporadically observed. Mucoepidermoid carcinoma and squamous carcinoma have been described in the literature. They present occasional papillary formation so that, according to some authors, could be considered as variants of the papillary carcinoma. Teratoma is another rare tumor which in the paediatric age is benign, but its prognosis could be unfavourable because it causes an important respiratory distress, while in the adult it presents a very aggressive clinical course like the anaplastic carcinoma. Lymphoma is the most frequent of the "rare" tumors of the thyroid (1-5% of all the thyroid cancers). It arises often in a setting of a long history of goitre and Hashimoto thyroiditis. Fine-needle aspirate is important to make diagnosis and to start a correct treatment which allows a 5-year survival up to 85% in the favourable cases.

Cloning and expression pattern of connexin39, a new member of the gap junction gene family isolated from the neural tube of chicken embryos

In this study, a new gap junction (GJ) connexin (Cx) gene was isolated from the neural tube of chicken (c) embryos (HH21) and cloned by degenerate reverse transcription-polymerase chain reaction (RT-PCR). The open reading frame of the gene encodes for a protein of 343 amino acid residues with strong similarity to highly conserved connexin sequences. On the basis of the predicted molecular mass of 39144 kDa, we denominated it as cCx39. Sequence analysis allocated the cCx39 to the alpha-group of connexin gene family. The mRNA expression of cCx39 was detected by RT-PCR and Northern blot in several tissues of chicken, including different parts of central nervous system, heart, liver, kidney, aorta and ovary. In situ hybridisation analysis of chicken brain showed strong expression in neurons of granular layers of cerebellum, optic tectum and ectostriatum. The in situ hybridisation of extracererebral tissues revealed strong expression of cCx39 in the atrium of the heart, the external layer of the aorta and endothelium of biliary vessels; moderate expression was found in the endothelium of the aorta.

Analysis of cCx39 expression pattern during chick development

The present study reports the expression pattern of connexin39 (cCx39) in chick embryos at different stages of central nervous system development. We examined the expression between HH17 and HH40 developmental stages of chicken embryos by in situ hybridization (ISH) technique. Connexin39 was first expressed at HH17. It stained neuroepithelial cells in the optic (OV) and telencephalic (TEL) vesicles, plus in the superficial mesenchyme of the two rostral branchial arches (maxilar and mandibular). These cells probably originated from the neural crest. This expression pattern changed drastically between stages HH17 and HH23, while it showed relatively little modifications from HH23 to HH29. At these times, connexin39 was expressed in three regions: the telencephalic vesicle, the diencephalon and the isthmus. At later stages, HH35 and HH40, connexin39 was mainly expressed in the ventricular epithelium and three cell layers of the stratum griseum and fibrosum superficialis (SGFS) in the optic tectum, as well as in granular and nuclear cells in the cerebellum. In conclusion, the expression pattern of connexin39 in embryonic nervous system is dynamic. This pattern is different from, and in some aspects complementary to, those showed by other connexins during brain development.

Towards improved clinical and physiological assessments of recovery in spinal cord injury: a clinical initiative

Clinical practice and scientific research may soon lead to treatments designed to repair spinal cord injury. Repair is likely to be partial in the first trials, extending only one or two segments below the original injury. Furthermore, treatments that are becoming available are likely to be applied to the thoracic spinal cord to minimise loss of function resulting from damage to surviving connections. These provisos have prompted research into the improvement of clinical and physiological tests designed (1) to determine the level and density of a spinal cord injury, (2) to provide reliable monitoring of recovery over one or two spinal cord segments, and (3) to provide indices of function provided by thoracic spinal root innervation, presently largely ignored in assessment of spinal cord injury. This article reviews progress of the Clinical Initiative, sponsored by the International Spinal Research Trust, to advance the clinical and physiological tests of sensory, motor and autonomic function needed to achieve these aims.

Apoptotic molecules and MPTP-induced cell death

MPTP-induced neurotoxicity is one of the experimental models most commonly used to study the pathogenesis of Parkinson's disease (PD). MPTP administered in vivo to mice causes selective loss of dopaminergic neurons in the substantia nigra (SN), as in this disease. Cell death may be induced in vitro by MPP(+), the active metabolite of MPTP, when neuronal cell cultures are used. Biochemical mechanisms underlying cell death induced by MPTP/MPP(+) still remain to be clarified completely. This article reviews some recent findings linking the effects of MPTP/MPP(+) with molecules typically involved in apoptotic pathways. This type of research has made extensive use of genetically manipulated systems such as transgenic mice and transfected cell lines. Evidence has emerged to suggest that Bcl-2, Bax, JNK, and caspases are implicated in neurotoxic effects due to in vivo MPTP administration to mice. Different neuronal cell lines such as MN9D cells, SH-SY5Y cells, cerebellar granule neurons, cortical neurons, and GH3 cells were also tested to investigate the possible involvement of Bcl-2, Bax, and caspases in in vitro MPP(+)-induced neurotoxicity.

Cell death induced by MPTP, a substrate for monoamine oxidase B

MPTP is known to cause PD symptoms in primates and in rodents. In order to exert its neurotoxicity MPTP must be converted by monoamine oxidase B into MPP(+) which is the true toxic agent. MPP(+) is taken up by the dopaminergic neurons of the substantia nigra in which it induces cell death. The present work reviews and discusses papers in which specific methods were used to determine whether cell death induced by MPTP/MPP(+) should be considered as apoptosis or necrosis. These two cell death modes may be distinguished using morphological and biochemical criteria. The effect of MPTP/MPP(+) was studied in vitro and in vivo. The results show that no univocal answer is possible. The most widespread interpretation is that MPTP/MPP(+) causes apoptosis when its neurotoxic effect is only sligh and necrosis when it is stronger. Similar considerations may be made also concerning the type of cell death occurring in the dopaminergic neurons in the substantia nigra of PD patients.

Phenotypic differences between African and white patients with motor neuron disease: a case-control study

There is increasing evidence that race may affect the phenotype in some neurodegenerative diseases. To investigate this in motor neuron disease a retrospective case-control study has been carried out on 15 negroid African and 45 white patients with the disease seen over 8 years. Each African was compared with three age and sex matched white patients with motor neuron disease. There were no statistically significant differences in age of onset or the mean duration of disease in the two groups. The chance of presenting with the "flail arm" variant of motor neuron disease was four times as high in the African group than the white group (odds ratio 4.33, p=0. 05, 95% confidence interval 0.99-18.92). Although no overall differences in survival were seen between the two groups, in those with the flail arm variant, four out of the six African patients had died whereas all six white arm patients were alive at the censoring date of 1 January 1999 (median follow up 38.5 months). It is concluded that race may influence the phenotype and progression of motor neuron disease.

Patterns of genotypic variation and phenotypic plasticity of light response in two tropical Piper (Piperaceae) species

Patterns of phenotypic plasticity and genotypic variation in light response of growth and photosynthesis were examined in two species of rain forest shrub that differ in ecological distribution within the forest. We further examined correlations among photosynthetic and growth traits. We hypothesized that the pioneer species, Piper sancti-felicis, would display greater phenotypic plasticity than the shade-tolerant species, Piper arieianum. We further proposed that, in both species, genotypic effects would be more apparent in growth-related traits than photosynthetic traits due to more concentrated selection pressure on gas-exchange traits. P. sancti-felicis did not demonstrate greater phenotypic plasticity of light response. Although many of the traits measured had significant genotype effects, neither species showed any significant effects of genotype on light response of photosynthesis, suggesting little genetic variation for this trait within populations. A principal components analysis clearly illustrated both species and light effects, with the treatments dividing neatly along the axis of the first principal component and the species separating along the second principal component axis. Results indicated general similarities between the species in their trait correlation structure and level of integration among traits, but characteristic differences were observed in the patterns of change between low and high light. Both species had more correlations than expected within groups of growth-related or photosynthetic traits; strong correlations of traits between these two groups were underrepresented. The similar pattern of genetic variation and phenotypic integration observed in these two congeners may be due more to their close phylogenetic relation than to their ecological distributions.

Propranolol induces polyspermy during sea urchin fertilization

Propranolol, a beta-adrenergic receptor blocker, is found to induce polyspermy in sea urchin eggs. Unfertilized sea urchin eggs treated for 10 min with 50 microM of propranolol, and then inseminated, become polyspermic and show a fertilization envelope which is barely visible to the light microscope. Examination of treated eggs by transmission and scanning electron microscopy shows that the drug does not alter the cortex of the unfertilized egg. However, after insemination an incomplete cortical reaction occurs. This might well account for both polyspermy and the defective elevation of the fertilization envelope. Since the effects of the drug are reversed by simultaneous treatment with adrenalin, perhaps propranolol interferes with the monoaminergic system that has been proposed to be active. The involvement of the monoaminergic system in the fertilization process is present in the sea urchin egg.

Holoacardius: antenatal diagnosis and pathogenetic evaluation: a case report

A case of Holoacardius is reported by the authors. The literature is reviewed, and a pathogenetic sequence responsible for the syndrome is proposed on the basis of the pathologic data.

Monoamine oxidase activity in embryos of pike (Esox lucius)

1. Mitochondrial MAO specific activity was measured in eggs and early embryos of the teleostean fish Esox lucius using tryptamine, 5-hydroxytryptamine (5-HT) and phenylethylamine (PEA) as substrates. 2. Tryptamine is the most readily deaminated substrate in mitochondria isolated from unfertilized eggs and embryos at the stages of cleavage, blastula and gastrula. 3. Monoamine oxidase activity gradually decreases during development and at the gastrula stage it is respectively 80% (tryptamine), 70% (5-HT) and 50% (PEA) of that found in the egg using the corresponding substrate. 4. The inhibition of egg MAO activity by clorgyline and deprenyl measured in E. lucius eggs using tryptamine as substrate, indicates the presence of a single form of MAO not corresponding to the MAO A and MAO B described in terrestrial vertebrates.

Propranolol, a beta-adrenergic receptor blocker, affects microfilament organization, but not microtubules, during the first division in sea urchin eggs

Propranolol, a beta-adrenergic receptor blocker, blocks the formation of the cleavage furrow, while karyokinesis is unaffected during first division in the sea urchins Paracentrotus lividus or Lytechinus pictus. This effect is reversed by adrenalin, indicating that it is mediated by an adrenergic mechanism. The staining of F-actin microfilaments by rhodamine phalloidin in eggs in which the cleavage is blocked by the drug has revealed that propranolol affects both the distribution and the organization of actin microfilaments. A low-voltage scanning electron microscopy (LVSEM) study of microvilli in these eggs shows an extensive rearrangement of the egg surface. Anti-tubulin immunofluorescence microscopy of eggs treated with propranolol shows that they form normal mitotic asters. This indicates that while cleavage is affected, mitotic spindle formation is not. These results suggest that neurotransmitter monoamines known to be present in the sea urchin egg might be involved in the reorganization of the actin cytoskeleton underlying the formation of the cleavage furrow.