Recommendations on the management of pudendal nerve entrapment syndrome: A formalised expert consensus

BACKGROUND

Since the development and publication of diagnostic criteria for pudendal nerve entrapment (PNE) syndrome in 2008, no comprehensive work has been published on the clinical knowledge in the management of this condition. The aim of this work was to develop recommendations on the diagnosis and the management of PNE.

METHODS

The methodology of this study was based on French High Authority for Health Method for the development of good practice and the literature review was based on the PRISMA method. The selected articles have all been evaluated according to the American Society of Interventional Pain Physicians assessment grid.

RESULTS

The results of the literature review and expert consensus are incorporated into 10 sections to describe diagnosis and management of PNE: (1) diagnosis of PNE, (2) patients advice and precautions, (3) drugs treatments, (4) physiotherapy, (5) transcutaneous electrostimulations (TENS), (6) psychotherapy, (7) injections, (8) surgery, (9) pulsed radiofrequency, and (10) Neuromodulation. The following major points should be noted: (i) the relevance of 4+1 Nantes criteria for diagnosis; (ii) the preference for initial monotherapy with tri-tetracyclics or gabapentinoids; (iii) the lack of effect of opiates, (iv) the likely relevance (pending more controlled studies) of physiotherapy, TENS and cognitive behavioural therapy; (v) the incertitudes (lack of data) regarding corticoid injections, (vi) surgery is a long term effective treatment and (vii) radiofrequency needs a longer follow-up to be currently proposed in this indication.

CONCLUSION

These recommendations should allow rational and homogeneous management of patients suffering from PNE. They should also allow to shorten the delays of management by directing the primary care.

SIGNIFICANCE

Pudendal nerve entrapment (PNE) has only been known for about 20 years and its management is heterogeneous from one practitioner to another. This work offers a synthesis of the literature and international experts' opinions on the diagnosis and management of PNE.

Acute pancreatitis following scoliosis surgery: description and clinical course in 14 adolescents

PURPOSE

Acute pancreatitis is a possible complication after scoliosis surgery. Although some risk factors have been documented in the literature, clinical description of pancreatitis diagnosis and ensuing course still remain very poor. The aim of this study was to describe characteristics of acute pancreatitis after scoliosis surgery.

METHODS

A descriptive, retrospective and single-center study of fourteen adolescents with postoperative acute pancreatitis after spine fusion surgery in scoliosis management between April 2003 and August 2012 was performed.

RESULTS

Acute pancreatitis occurred within 9.5 days (4-51) after surgery. Abdominal pain was atypical and was expressed in only half of the children. Ileus, nausea and vomiting were the most frequent signs. None of the acute pancreatitis cases was severe.

CONCLUSION

Acute pancreatitis is an early complication of scoliosis surgery. Clinical signs are atypical and non-severe and can induce misleading forms. Presence of delayed digestive problems should alert the clinician to the risk of pancreatitis in the aftermath of scoliosis surgery.

Pre-clinical efficacy of combined therapy with novel β-catenin antagonist BC2059 and histone deacetylase inhibitor against AML cells

The canonical WNT-β-catenin pathway is essential for self-renewal, growth and survival of AML stem/blast progenitor cells (BPCs). Deregulated WNT signaling inhibits degradation of β-catenin, causing increased nuclear translocation and co-factor activity of β-catenin with the transcriptional regulator TCF4/LEF1 in AML BPCs. Here, we determined the pre-clinical anti-AML activity of the anthraquinone oxime-analog BC2059 (BC), known to attenuate β-catenin levels. BC treatment disrupted the binding of β-catenin with the scaffold protein TBL1 (transducin β-like 1) and proteasomal degradation and decline in the nuclear levels of β-catenin. This was associated with reduced transcriptional activity of TCF4 and expression of its target genes, cyclin D1, c-MYC and survivin. BC treatment dose-dependently induced apoptosis of cultured and primary AML BPCs. Treatment with BC also significantly improved the median survival of immune-depleted mice engrafted with either cultured or primary AML BPCs exhibiting nuclear expression of β-catenin. Co-treatment with the pan-histone deacetylase inhibitor panobinostat and BC synergistically induced apoptosis of cultured and primary AML BPCs, including those expressing FLT3-ITD, as well as further significantly improved the survival of immune-depleted mice engrafted with primary AML BPCs. These findings underscore the promising pre-clinical activity and warrant further testing of BC against human AML, especially those expressing FLT3-ITD.

Functional MR imaging in assessment of language dominance in epileptic patients

The value of functional MR Imaging (fMRI) in assessing language lateralization in epileptic patients candidate for surgical treatment is increasingly recognized. However few data are available for left-handed patients. Moreover determining factors for atypical dominance in patients investigated with contemporary imaging have not been reported. We studied 20 patients (14 males, 6 females; 9 right handed, 11 left handed) aged from 9 to 48 years, investigated for intractable partial epilepsy. Epileptic focus location was temporal in 14 cases, extratemporal in 6, and lateralized in the left hemisphere in 11/20. Hemispheric dominance for language was evaluated by both Wada test and fMRI using a silent word generation paradigm in all patients. Furthermore, a postictal speech test was performed in 15 patients. An fMRI language lateralization index was calculated from the number of activated pixels (Student's t test, P < 0.0001) in the right and left hemispheres. The Wada test showed a right hemispheric dominance in 8 patients (6 were left handed and 2 right handed) and a left hemispheric dominance in 12 patients (5 were left handed and 7 right handed). These results were concordant with clinical postictal examination in 11/15 patients (73%). Clinical status did not allow a conclusion about hemispheric dominance for the remaining 4 patients. FMRI was concordant with the Wada test in 19/20 cases. For one left-handed patient, fMRI showed bilateral activation, whereas the Wada test demonstrated a right hemispheric dominance. Right language lateralization was significantly correlated with left lateralized epilepsy (P < 0.05) but was not correlated with age at epilepsy onset, early brain injury (before 6 years), and lobar localization of epileptogenic focus. However the lack of a significant relationship between these factors and atypical language lateralization may be related to the small sample size.

[Diagnosis of periventricular ependymal enhancement in MRI in adults]

Periventricular enhancement in adults at MRI is a significant finding since it often indicates the presence of an underlying disease requiring prompt medical attention. From a review of patients with periventricular enhancement, the main imaging features based on the underlying infectious or tumoral etiology will be described. The presented differential diagnosis is based on the immune status of the patient, type of enhancement, and response to a trial therapy. In immunocompromised patients, the main considerations are lymphoma and viral ependymitis. The pattern of enhancement is important. The presence of thin linear enhancement suggests a viral etiology (cytomegalovirus or varicella-zoster virus) that can be confirmed at CSF evaluation whereas the presence of nodular enhancement suggests a diagnosis of primary CNS lymphoma that can be confirmed by the presence of lymphomatous cells in the CSF or, more frequently, at stereotactic surgical biopsy performed after failure of response to anti-toxoplasmosis treatment. The presence of band enhancement is less specific and can be seen with viral, lymphomatous and even tuberculous involvement. In immunocompetent patients, a clinical context of infection will suggest bacterial or tuberculous ventriculitis and the presence of cystic lesions will suggest cysticercosis; in the absence of constitutional symptoms, the presence of nodular enhancement will suggest a tumoral process (lymphoma, ependymoma, germ cell tumor, or metastases). Rarely, linear enhancement will be due to sarcoidosis or Whipple's disease.

Multimodal anatomic, functional, and metabolic brain imaging for tumor resection

OBJECTIVE

Improvement of neurosurgical techniques with a more detailed description of brain tumors and their functional environment.

METHODS

We performed: (1) anatomical magnetic resonance imaging (MRI) for reference, (2) functional sequences dedicated to the adjacent cortical structures (sensorimotor, visual, language paradigms), and (3) thallium 201 cerebral tomoscintigraphy to visualize active tumor invasion. Data were transferred to a workstation for automatic registration.

RESULTS

All data were combined into one synthetic image showing the foci of high proliferative activity, which have to be completely resected, and the peritumoral functional structures, which have to be spared in order to minimize postoperative sequelae. This trimodal image is entered into a surgical neuronavigation computer for preoperative planning in order to outline tumoral target and functional risk areas. All this information is displayed in the operative microscope (Zeiss MKM) optically linked to MR images. This multimodality technique diminishes operative time by reducing electrocorticography and improves the operative short-term outcome.

CONCLUSION

Multimodal imaging is useful for optimization of neurosurgical tumor resection.

Sensorimotor cortical activity in patients with complete spinal cord injury: a functional magnetic resonance imaging study

Residual activation of the cortex was investigated in nine patients with complete spinal cord injury between T6 and L1 by functional magnetic resonance imaging (fMRI). Brain activations were recorded under four conditions: (1) a patient attempting to move his toes with flexion-extension, (2) a patient imagining the same movement, (3) passive proprio-somesthesic stimulation of the big toes without visual control, and (4) passive proprio-somesthesic stimulation of the big toes with visual control by the patient. Passive proprio-somesthesic stimulation of the toes generated activation posterior to the central sulcus in the three patients who also showed a somesthesic evoked potential response to somesthesic stimulation. When performed under visual control, activations were observed in two more patients. In all patients, activations were found in the cortical areas involved in motor control (i.e., primary sensorimotor cortex, premotor regions and supplementary motor area [SMA]) during attempts to move or mental imagery of these tasks. It is concluded that even several years after injury with some local cortical reorganization, activation of lower limb cortical networks can be generated either by the attempt to move, the mental evocation of the action, or the visual feedback of a passive proprio-somesthesic stimulation.

Familial form of cerebral cavernous malformations: evaluation of gradient-spin-echo (GRASE) imaging in lesion detection and characterization at 1.5 T

The purpose of this study was to evaluate the turbo gradient-spin-echo sequence (GRASE) in the MR assessment of the familial form of cerebral cavernous malformations (CCM). Twenty-one patients (15 male, six female) aged from 21 to 68 years (mean = 42.2 years) were prospectively examined with cerebral MR imaging, including T2-weighted turbo gradient-spin-echo (TGSE), turbo spin-echo (TSE) and gradient-echo (GRE) sequences. All sequences were performed in the same plane, the same matrix and the same field of view and were analyzed for signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), susceptibility effects, number of CCM, size of CCM and signal of CCM. It was found that SNR and CNR in the TGSE sequence were significantly inferior to those in both TSE and GRE sequences. TGSE and TSE sequences were significantly less prone to susceptibility effects than the GRE sequence. The sensitivity of TGSE and TSE sequences in detecting CCM was significantly lower than that of the GRE sequence. TGSE and TSE sequences provided comparable information about CCM size and signal. It was concluded that GRASE imaging was less sensitive than the GRE sequence in the detection of CCM and provided information similar to that yielded by the TSE sequence in the characterization of lesions, but with a higher number of artifacts. GRASE imaging cannot therefore replace TSE or GRE sequences in the MR evaluation of the familial form of CCM.

Ca2+-dependent regulation of synaptic SNARE complex assembly via a calmodulin- and phospholipid-binding domain of synaptobrevin

Synaptic core complex formation is an essential step in exocytosis, and assembly into a superhelical structure may drive synaptic vesicle fusion. To ascertain how Ca(2+) could regulate this process, we examined calmodulin binding to recombinant core complex components. Surface plasmon resonance and pull-down assays revealed Ca(2+)-dependent calmodulin binding (K(d) = 500 nM) to glutathione S-transferase fusion proteins containing synaptobrevin (VAMP 2) domains but not to syntaxin 1 or synaptosomal-associated protein of 25 kDa (SNAP-25). Deletion mutations, tetanus toxin cleavage, and peptide synthesis localized the calmodulin-binding domain to VAMP(77-94), immediately C-terminal to the tetanus toxin cleavage site (Q(76)-F(77)). In isolated synaptic vesicles, Ca(2+)/calmodulin protected native membrane-inserted VAMP from proteolysis by tetanus toxin. Assembly of a (35)S-SNAP-25, syntaxin 1 GST-VAMP(1-96) complex was inhibited by Ca(2+)/calmodulin, but assembly did not mask subsequent accessibility of the calmodulin-binding domain. The same domain contains a predicted phospholipid interaction site. SPR revealed calcium-independent interactions between VAMP(77-94) and liposomes containing phosphatidylserine, which blocked calmodulin binding. Circular dichroism spectroscopy demonstrated that the calmodulin/phospholipid-binding peptide displayed a significant increase in alphahelical content in a hydrophobic environment. These data provide insight into the mechanisms by which Ca(2+) may regulate synaptic core complex assembly and protein interactions with membrane bilayers during exocytosis.

Direct interaction between synaptotagmin and the intracellular loop I-II of neuronal voltage-sensitive sodium channels

Synaptotagmin, a synaptic vesicle protein involved in Ca(2+)-regulated exocytosis, displayed direct high affinity interaction with neuronal sodium channels. Monoclonal antibodies directed against synaptotagmins I and II adsorbed in a concentration-dependent and -specific manner [(3)H]saxitoxin prelabeled sodium channels extracted with detergent from nerve endings. Conversely, co-immunoprecipitation of synaptotagmin was achieved by antibodies against sodium channel subunits. Consistent with the co-immunoprecipitation assays, solubilized [(3)H]saxitoxin-prelabeled sodium channels were trapped on immobilized maltose binding protein (MBP)-synaptotagmin I. In vitro recombinant protein assays were employed to identify the interaction site of synaptotagmin I, which was located on the cytoplasmic loop between domains I and II of the sodium channel alphaIIA subunit. The co-immunoprecipitated synaptotagmin-sodium channel complexes were found to be Ca(2+)-dependent; this effect was mimicked by Ba(2+) and Sr(2+) but not Mg(2+). Finally the complex was shown to be distinct from the synaptotagmin-SNARE protein complex that can selectively interact with presynaptic calcium channels (N and P/Q types). Thus, our findings demonstrate an unexpected and direct interaction between sodium channels and synaptotagmin. The Ca(2+)-regulated association between sodium channels and a protein implicated in vesicular fusion may have intriguing consequences for the establishment and regulation of neuronal excitability.

Recruitment of primitive peripheral blood cells: synergism of interleukin 12 with interleukin 6 and stromal cell-derived FACTOR-1

In bone marrow, haematopoietic stem cells (HSC) rely on close contact with stromal cells for proliferation and differentiation. Stromal cell-derived factor (SDF-1) is a chemokine produced by bone marrow stromal cells and has been reported to be a chemoattractant for CD34(+)cells. SDF-1 was evaluated for effects on proliferation of both mature and immature human progenitor cells in vitro. Neither proliferation nor maturation of peripheral blood cells was stimulated by SDF-1 alone. Moreover, we have previously demonstrated that 5-fluorouracile (5-FU) resistant HSC require a combination of interleukin 12 (IL-12), IL-6 and SCF for the production of morphologically recognizable clonogenic elements at day 14 in semisolid medium. Our data reported a strong enhancement of the IL-6, IL-12, SCF-induced synergism (172%) by SDF-1 (296.5%). Furthermore, our data suggest that this chemokine alone had no effect on triggering quiescent cells and may preserve these cells from 5-FU cell damage or upregulate early-acting cytokine receptors. Thus, SDF-1 might play a key role in early human haematopoiesis through its potent synergistic effects in combination with early-acting cytokines. These results suggest that a programmed response to sequential cytokine stimulation may be part of a control mechanism required for maintenance of proliferation of primitive HSC.

Calcium-dependent dissociation of synaptotagmin from synaptic SNARE complexes

The formation of the synaptic core (SNARE) complex constitutes a crucial step in synaptic vesicle fusion at the nerve terminal. The interaction of synaptotagmin I with this complex potentially provides a means of conferring Ca2+-dependent regulation of exocytosis. However, the subcellular compartments in which interactions occur and their modulation by Ca2+ influx remain obscure. Sodium dodecyl sulfate (SDS)-resistant core complexes, associated with synaptotagmin I, were enriched in rat brain fractions containing plasma membranes and docked synaptic vesicles. Depolarization of synaptosomes triggered [3H]GABA release and Ca2+-dependent dissociation of synaptotagmin from the core complex. In perforated synaptosomes, synaptotagmin dissociation was induced by Ca2+ (30-300 microM) but not Sr2+ (1 mM); it apparently required intact membrane bilayers but did not result in disassembly of trimeric SNARE complexes. Synaptotagmin was not associated with unstable v-SNARE/t-SNARE complexes, present in fractions containing synaptic vesicles and cytoplasm. These complexes acquired SDS resistance when N-ethylmaleimide-sensitive fusion protein (NSF) was inhibited with N-ethylmaleimide or adenosine 5'-O-(3-thiotriphosphate), suggesting that constitutive SNARE complex disassembly occurs in undocked synaptic vesicles. Our findings are consistent with models in which the Ca2+ triggered release of synaptotagmin precedes vesicle fusion. NSF may then dissociate ternary core complexes captured by endocytosis and recycle/prime individual SNARE proteins.

Effects of glucocorticoids and mineralocorticoids on proliferation and maturation of human peripheral blood stem cells

It has been shown that hematopoietic progenitors can be expanded ex vivo in the presence of various cytokine combinations. Glucocorticoids (GC) are involved in the self-renewal of erythroid progenitors in chicken. To see whether GC have a similar effect on hematopoiesis in humans, CD34(+) peripheral blood stem cells were cultured in serum free medium in the presence of a GC, triamcinolone acetonide. However, our results demonstrate an inhibition of both erythroid and granulocyte-macrophage (GM) proliferation and a modification of erythroid colony morphology. Furthermore, RU38486 (Mifepristone), a potent GC antagonist, was unable to reverse the inhibitory effect of triamcinolone acetonide. We also identified and characterized another steroid subfamily, the mineralocorticoid (MC) subfamily, in human PB CD34(+) cells. The MC, aldosterone, significantly enhanced GM colony formation and diminished the erythroid colony number. Neither of effects were inhibited by ZK91587, an antagonist specific to the MC receptor (MCR). In contrast, ZK91587 reversed the stimulatory effect of deoxycorticosterone on GM colony formation. Cytoplasmic staining for MCR was observed in CD34(+) cells incubated with a polyclonal antiserum raised against human MCR. To our knowledge, this is the first demonstration of the presence of MCR in human PB CD34(+) cells.

Effects of glucocorticoids and mineralocorticoids on proliferation and maturation of human peripheral blood stem cells

It has been shown that hematopoietic progenitors can be expanded ex vivo in the presence of various cytokine combinations. Glucocorticoids (GC) are involved in the self-renewal of erythroid progenitors in chicken. To see whether GC have a similar effect on hematopoiesis in humans, CD34(+) peripheral blood stem cells were cultured in serum free medium in the presence of a GC, triamcinolone acetonide. However, our results demonstrate an inhibition of both erythroid and granulocyte-macrophage (GM) proliferation and a modification of erythroid colony morphology. Furthermore, RU38486 (Mifepristone), a potent GC antagonist, was unable to reverse the inhibitory effect of triamcinolone acetonide. We also identified and characterized another steroid subfamily, the mineralocorticoid (MC) subfamily, in human PB CD34(+) cells. The MC, aldosterone, significantly enhanced GM colony formation and diminished the erythroid colony number. Neither of effects were inhibited by ZK91587, an antagonist specific to the MC receptor (MCR). In contrast, ZK91587 reversed the stimulatory effect of deoxycorticosterone on GM colony formation. Cytoplasmic staining for MCR was observed in CD34(+) cells incubated with a polyclonal antiserum raised against human MCR. To our knowledge, this is the first demonstration of the presence of MCR in human PB CD34(+) cells.

Study of the joint space of the hip on supine and weight-bearing digital radiographs

AIM

To compare hip joint space on supine and weight-bearing anteroposterior digital radiographs.

MATERIALS AND METHODS

Fifty anteroposterior views of the hip in 25 patients were taken in supine and weight-bearing positions on a fluoroscopic unit. Two observers in a double-blind study assessed the width of the joint space on an Easy Vision unit with an indirect method of measurement (metric index).

RESULTS

Inter-observer and intra-observer variabilities of the metric index were less than 4.1%. There was no significant difference of the metric index of the hip (P>0.05), between supine and weight-bearing positions.

CONCLUSION

There is no significant difference of the width of the joint space of the hip between supine and weight-bearing anteroposterior radiographs. Measuring joint space loss in osteoarthritis of the hip with anteroposterior views should be done with radiographs of the hip in the supine position to improve image quality.

Recruitment of primitive peripheral blood cells: synergism of interleukin 12 with interleukin 6 and stem cell factor

Interleukin-12 (IL-12), a heterodimeric cytokine with potent biological activity, was evaluated for effects on proliferation of human immature progenitor cells in vitro. In vitro proliferation of 5-FU-resistant CD34+ (G0) peripheral blood stem cells (PBSC) in response to sequential cytokine stimulation was examined in the presence and absence of 100 ng/ml IL-12. PBSC were found to include a subpopulation of cells that were resistant to 25 microg/ml 5-FU and required a combination of IL-12, IL-6 and SCF for the production of morphologically recognizable clonogenic elements at day 14 in semisolid medium. Furthermore, addition of IL-6 soluble receptor (IL-6Rs) to IL-6 and SCF led to a similar recruitment. We also demonstrated a significant production of IL-6Rs by CD34+ cells stimulated by IL-12. We noted that glucocorticoids and aldosterone, a mineralocorticoid, had a positive effect on recruitment, but neither mineralocorticoid nor glucocorticoids induced IL-6Rs production by CD34+ cells. The recruitment mechanism by steroids seemed to be different from that used by IL-12. These results confirm previous findings which showed the involvement of IL-12 on immature PBSCs and suggest that IL-12 might play a key role in early haemopoiesis.

Environmental Assessment of Larvicide Use in the Onchocerciasis Control Programme

The objective of the Onchocerciasis Control Programme (OCP) is to eliminate onchocerciasis as a disease of public importance and as an obstacle to socio-economic development. The OCP was initially based solely on the control of the blackfly vector, Simulium damnosum sensu lato, by insecticide spraying of the breeding sites on river systems, where larval stages develop. Results of monitoring the environmental effects and the process of risk assessment for new insecticides are reviewed. The achievements of this strategy are outlined here by Davide Calamari, Laurent Yameogo, Jean-Marc Hougard and Christian Leveque.

Interaction of cysteine string proteins with the alpha1A subunit of the P/Q-type calcium channel

Cysteine string proteins (Csps) are J-domain chaperone proteins anchored at the surface of synaptic vesicles. Csps are involved in neurotransmitter release and may modulate presynaptic calcium channel activity, although the molecular mechanisms are unknown. Interactions between Csps, proteins of the synaptic core (SNARE) complex, and P/Q-type calcium channels were therefore explored. Co-immunoprecipitation suggested that Csps occur in complexes containing synaptobrevin (VAMP), but not syntaxin 1, SNAP-25, nor P/Q-type calcium channels labeled with 125I-omega-conotoxin MVIIC. However binding experiments with 35S-labeled Csp1 demonstrated an interaction (apparent KD = 700 nM at pH 7.4 and 4 degreesC) with a fusion protein containing a segment of the cytoplasmic loop linking homologous domains II-III of the alpha1A calcium channel subunit (BI isoform, residues 780-969). Binding was specific as it was displaced by unlabeled Csp1, and no interactions were detected with fusion proteins containing other calcium channel domains, VAMP, or syntaxin 1A. A Csp binding site on the P/Q-type calcium channel is thus located within the 200 residue synaptic protein interaction site that can also bind syntaxin I, SNAP-25, and synaptotagmin I. Csp may act as a molecular chaperone to direct assembly or disassembly of exocytotic complexes at the calcium channel.

Cysteine string proteins associated with secretory granules of the rat neurohypophysis

The properties and subcellular distribution of cysteine string proteins (csps) were analyzed in peptidergic nerve terminals of the rat neurohypophysis. Polyclonal antibodies raised against recombinant rat brain csp recognized a 36 kDa protein in isolated neurosecretosomes from the post-pituitary. After chemical deacylation, a single 27 kDa form was detected that displayed identical properties to csps in a whole-brain synaptosomal fraction. Immunoisolation demonstrated that synaptophysin and csps were located in the same vesicles. Density gradient centrifugation of postsynaptosomal supernatants of neurohypophysial homogenates revealed that csps and VAMP were present in two distinct vesicle populations. Synaptophysin was only detected in the slowly migrating population corresponding to small synaptic vesicles, whereas arginine vasopressin was present in the more rapidly sedimenting population indicating that it contains large dense core vesicles (LDCVs). Immobilized antibodies against csp, synaptotagmin, or VAMP captured vesicular arginine vasopressin confirming the association of these proteins with LDCVs. Co-immunoprecipitation assays with proteins solubilized from neurohypophysial or whole-brain nerve terminals failed to reveal complexes containing csp and [125I]omegaGVIA receptors. These results indicate that csps in the CNS are associated with both small synaptic vesicles and LDCVs. However, they do not provide support for the hypothesis that protein complexes implicated in exocytosis, which interact with presynaptic N-type calcium channels, contain csps.

Interaction of SNARE complexes with P/Q-type calcium channels in rat cerebellar synaptosomes

P- and Q-type calcium channels, which trigger rapid neurotransmitter release at many mammalian synapses, are blocked by omega-conotoxin MVIIC. 125I-omega-Conotoxin MVIIC binding to rat cerebellar synaptosomes was not displaced by omega-conotoxins GVIA or MVIIA (Ki > 1 microM), which are selective for N-type calcium channels. Solubilized 125I-omega-conotoxin MVIIC receptors were specifically recognized by antibodies directed against alpha1A calcium channel subunits, proteins known to constitute a pore with P/Q-like channel properties. Antibodies against syntaxin 1, SNAP 25, and VAMP 2 (synaptobrevin) each immunoprecipitated a similar fraction (20-40%) of omega-conotoxin MVIIC receptors. Immunoprecipitation was not additive, suggesting that heterotrimeric (SNARE) complexes containing these three proteins interact with P/Q-type calcium channels. Immobilized monoclonal anti-syntaxin antibodies retained alpha1A calcium channel subunits of 220, 180 and 160 kDa monitored by immunoblotting with site directed antibodies. Synaptotagmin was detected in channel-associated complexes, but not synaptophysin, Rab 3A nor rat cysteine string protein. Trimeric SNARE complexes are implicated in calcium-dependent exocytosis, a process thought to be regulated by synaptotagmin. Our results indicate that these proteins interact with P/Q-type calcium channels, which may optimize their location within domains of calcium influx.

Properties of omega conotoxin MVIIC receptors associated with alpha 1A calcium channel subunits in rat brain

Solubilized 125I-omega conotoxin MVIIC receptors from rat cerebellum were immunoprecipitated by antibodies directed against the calcium channel alpha 1A subunit. Anti-alpha 1A antibodies recognized a 240-220, 180 and 160 kDa proteins in immunoblots of cerebellar membranes. Disuccinimidyl suberate cross-linked 125I-omega conotoxin MVIIC to an alpha 2 delta-like 200-180 kDa subunit, which migrated at 150-140 kDa after disulfide reduction. These observations are consistent with a heteromeric structure in which high affinity omega conotoxin MVIIC binding sites formed by alpha 1A subunits are located in close proximity to peripheral alpha 2 subunits.

Antigens associated with N- and L-type calcium channels in Lambert-Eaton myasthenic syndrome

In Lambert-Eaton myasthenic syndrome neurotransmitter release is reduced by an autoimmune response directed against the calcium channel complex of the nerve terminal. Autoantibodies were detected by immunoprecipitation assays using solubilized receptors labeled with ligands selective for N-type (125I-omega conotoxin GVIA) and L-type ([3H]PN200-110) calcium channels. Sera with a high antibody titer (> 3 nM) against rat brain N-type channels contained autoantibodies that immunoprecipitated neuronal and muscle L-type channels. These IgG fractions stained a 55-kDa protein in immunoblots of purified skeletal muscle dihydropyridine receptor, suggesting that they contain autoantibodies against the beta subunit of the calcium channel. A distinct antibody population in the same fractions reacted with a nerve terminal 65-kDa protein that is unrelated to the beta subunit and displays properties similar to those of synaptotagmin.

Interaction of a synaptobrevin (VAMP)-syntaxin complex with presynaptic calcium channels

Nerve terminal protein complexes implicated in exocytosis were examined by immuno-isolation from rat brain synaptosomes. Immunoprecipitation with anti-syntaxin or anti-VAMP antibodies revealed a syntaxin-SNAP25-VAMP-synaptotagmin complex. Anti-VAMP antibodies also trapped a distinct VAMP-synaptophysin complex. A similar fraction (about 70%) of N-type calcium channels ([125I]omega conotoxin GVIA receptors), was immunoprecipitated by either anti-syntaxin or anti-VAMP antibodies, but not by anti-synaptophysin antibodies (< 4%). The majority of N- but not L-type calcium channels ([3H]PN200-110 receptors), appear to be associated with a synaptic vesicle prefusion complex.

Interaction of synaptotagmin with voltage gated calcium channels: a role in Lambert-Eaton myasthenic syndrome?

Plasma from patients with Lambert-Eaton myasthenic syndrome (LEMS), an autoimmune disease of neuromuscular transmission, contains antibodies that bind to the synaptic vesicle protein synaptotagmin. Synaptotagmin associates with calcium channels and appears to regulate synaptic vesicle docking at the plasma membrane prior to rapid neurotransmitter release. Autoantibodies directed against a synaptotagmin-calcium channel complex may be involved in the etiology of LEMS. In the majority of patients LEMS is associated with small cell lung cancer (SCLC). We have detected the expression of proteins of the secretory pathway, including synaptotagmin, syntaxin and N-type calcium channels, in a panel of SCLC tumor lines. These observations are compatible with the hypothesis that the initial autoimmune response in LEMS is triggered by the tumor.

Synaptotagmin: a Lambert-Eaton myasthenic syndrome antigen that associates with presynaptic calcium channels

Plasma from patients with Lambert-Eaton myasthenic syndrome (LEMS), an autoimmune disease of neuromuscular transmission, contains antibodies that immunoprecipitate 125I-omega-conotoxin GVIA labeled-calcium channels solubilized from rat brain. These antibodies label a 58-kDa protein in Western blots of partially purified 125I-omega-conotoxin receptor preparations. Monoclonal antibody 1D12, produced by immunizing mice with synaptic membranes, has similar properties as these LEMS IgG. 1D12 antigen was purified by immunoaffinity chromatography and shown to bind LEMS IgG. The antigen was identified by immunoscreening a rat brain cDNA library with mAb 1D12 and found to have strong homology to the synaptic vesicle protein synaptotagmin. These antibodies immunoprecipitate calcium channels by binding to synpatotagmin, an associated protein. We suggest that the interaction between synaptotagmin and omega-conotoxin sensitive calcium channels plays a role in docking synaptic vesicles at the plasma membrane prior to rapid neurotransmitter release. Autoantibody binding to a synaptotagmin-calcium channel complex may be involved in the etiology of LEMS.

The synaptic vesicle protein synaptotagmin associates with calcium channels and is a putative Lambert-Eaton myasthenic syndrome antigen

Immunoglobulin G fractions from patients with Lambert-Eaton myasthenic syndrome (LEMS), an autoimmune disease of neuromuscular transmission, immunoprecipitate 125I-labeled omega-conotoxin GVIA-labeled calcium channels solubilized from rat brain. A 58-kDa antigen was detected by probing Western blots of partially purified calcium channels with LEMS plasma and IgG and was shown to be the relevant antigen in omega-conotoxin receptor immunoprecipitation. Monoclonal antibody 1D12, produced by immunizing mice with synaptic membranes, has properties similar to these autoimmune IgGs in both immunoprecipitation and Western blotting assays. 1D12 antigen was purified by immunoaffinity chromatography and shown to bind LEMS IgG. The antigen was identified by screening a rat brain cDNA library with 1D12 and was found to have strong homology to the synaptic vesicle membrane protein synaptotagmin. Our results indicate therefore that these antibodies immunoprecipitate omega-conotoxin receptors by binding to synaptotagmin that is associated with calcium channels. We suggest that the interaction between synaptotagmin and the voltage-gated calcium channel plays a role in docking synaptic vesicles at the plasma membrane prior to rapid neurotransmitter release and that autoantibody binding to a synaptotagmin-calcium-channel complex may be involved in the etiology of LEMS.

[Evaluation of 5 years of experimental in utero surgery for the repair of diaphragmatic hernia]

The incidence of diaphragmatic hernia in he newborn is 1:2,500 to 5,000 births. An extensive American programme of foetal surgery for in utero repair of this defect has shown that the pulmonary hypoplasia was due to compression of lung tissue by the herniated organs. This process could be interrupted be repairing the diaphragmatic defect early enough in utero (before the 28th week). The results of five years of experimental surgery for in utero correction of diaphragmatic hernia are presented here. The experimental model used was the Macaca fascicularis monkey, the pregnant female of which having several gestational and endocrine characteristics similar to those of the pregnant woman. Three different experimental programmes were carried out successively. A first series including five animals was used to experiment both surgical and anaesthetic techniques; three foetuses died in utero. The second series (10 animals) was designed to find a suitable protocol for tocolysis. One female died after surgery, and seven other foetuses also died. The third group (13 animals) was the main study group. The diaphragmatic hernia was first created surgically, and then repaired. No foetus died from the surgery. One female died before giving birth, and one offspring died shortly after birth as its mother had no milk. After the encouraging results obtained with this last series of animals, the procedure was applied to human cases, with the Hospital Ethical Committee's approval. In the first case, the foetus died postoperatively as a result of the rupture of the diaphragmatic prosthesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Polypeptide components of the apamin receptor associated with a calcium activated potassium channel

Photoaffinity labeling of rat brain membranes with [125I]ANPAA-apamin incorporated radioactivity into polypeptides of 86 and 59 kDa and occasionally a more weakly labeled component of 45 kDa. These polypeptides were immunoprecipitated with anti-apamin antibodies and treated with glycosidases. Neither the 86 nor the 59 kDa polypeptide appeared to be N-glycosylated. Partial proteolytic mapping of affinity labeled polypeptides with chymotrypsin or V8 protease generated an identical pattern. These results suggest that the 59 and 45 kDa components are not additional subunits of an oligomeric protein but result from cleavage of the 86 kDa polypeptide.

Fatal disseminated cryptococcosis following intraocular involvement

A 33-year-old man was treated with systemic steroids for a retinal inflammatory lesion before the diagnosis of cryptococcal retinitis and meningitis was suspected. He died from central nervous system disease despite treatment with parenteral antifungals. Histopathological studies demonstrated ocular and disseminated systemic infection with Cryptococcus neoformans. Direct cryptococcal involvement of the eye is rare and is usually associated with disseminated disease. Systemic steroids must be used with caution, and patients who take these drugs require frequent monitoring.

[Charcot-Marie-Tooth disease and glomerular nephropathy]

Anatomoclinical profile and follow-up of a glomerular nephropathy in a prepubertal girl with Charcot-Marie-Tooth disease is reported; striking common pattern features with the few cases previously published of such an association strongly suggest that renal involvement is possible in sensorineural neuropathies and may be one major factor in the overall prognosis of the disease.

Pharmacology of vecuronium in patients with end-stage renal failure

Vecuronium was administered as an intravenous bolus (50 micrograms kg-1) to 10 normal and 10 anephric patients. The elimination half-life was 50.7 +/- 20.3 min in normal patients and 67.826.3 min in anephric patients. The plasma clearance was 3.6 +/- 1.5 ml min-1 for normal patients and 4.5 +/- 2.6 ml min-1 kg-1 for anephric patients. Only the volume of the second compartment was statistically increased (+90%, P less than 0.05) in anephric patients. The duration of action in normal patients (25.3 +/- 9.8 min) was comparable to the duration of action in patients with renal failure (32.8 +/- 10.7 min), but the recovery index was prolonged (+45%, P less than 0.05) in anephric patients.

[Parietal complications of cholecystectomy : results of prophylactic antibiotic therapy with cefazoline (author's transl)]

Patients undergoing cholecystectomy were randomly divided into two groups. The effects of a single injection of one gram of cefazoline given thirty minutes before operation to 30 patients were compared with those obtained in a second group of 29 untreated cases. The efficiency of the second generation cephalosporins in preventing postoperative complications of this type was confirmed. Prophylactic administration of this antibiotic therapy before uncomplicated biliary tract surgery can significantly reduce the incidence of postoperative parietal infections and therefore the duration of hospitalization.

[Influence of some medium factors on the fecundity of Biomphalaria glabrata (Say, 1818) Mollusca, Pulmonata) in laboratory conditions]

In different samples of fresh waters we studied the fecundity of Biomphalaria glabrata. We tested, too, the influence of different concentrations of Na, Ca, Mg, and K-salts. The snail, B. glabrata, is not affected by very high rates of those salts but eggs laying is getting down when the amount of NaCl is between 2000 and 4000 mg/1, of MgCl2 between 410 and 763 mg/1 and KCl between 330 and 760 mg/1. The rate in Ca seems inactive in the field of fecundity but, in an other hand, high concentrations of Ca suppressed the inhibiting effect of the high rates in Mg. B. glabrata is not affected by high rates in Mg, when Mg/Ca is Low. The inhibiting effect of Mg begins when Mg/Ca is around 30. The importance of different kinds of substratum for eggs lying on fecundity was also studied.

Study of growth of Biomphalaria glabrata Say and other Planorbidae in Guadeloupe West Indies

The growth of Biomphalaria glabrata, B. schrammi, Drepanotrema lucidum and D. kermatoides was studied in three habitatis on Guadeloupe. Theortical growth curves were calculated for each species by applying the Walford method and the von Bertalanffy equation. On Guadeloupe, the growth of B. glabrata was faster in the ponds of Grand Terre than in the small high altitude streams of Basse Terre. There is good correlation between the observations made in Guadeloupe and previous data obtained on Pureto Rico and St Lucia.