Biomedical subjects

D Liguoro

Publications and source records attributed to D Liguoro.

At least 19 recordsLinked to original sources

PubMed2006

beta(2)-Microglobulin amyloidosis caused spinal cord compression in a long-term haemodialysis patient.

STUDY DESIGN: A case report of cervical myelopathy caused by epidural beta (2)-microglobulin (beta2m) amyloid deposits in a 50-year-old woman with haemodialysis treatment. OBJECTIVE: Long-term haemodialysis in patients with end-stage renal disease leads to several complications based on beta2m deposits, which can affect, in the cervical spine, the intervertebral disk, and in rare cases, they may compress the spinal cord and nerves. The objective of this report is to describe the clinical and radiological follow-up preceding the indispensable surgical excision of an amyloid mass in a 50-year-old woman with haemodialysis treatment. Long-term postoperative cervicalgia owing to subcondylian bone cyst-associated atlanto-occipital instability is also described and discussed. SETTING: Department of Neurosurgery A, Hop Pellegrin, Bordeaux, France. CASE REPORT: We present a clinical case of a patient with spinal cord compression. The patient was treated by surgical excision of an amyloid mass subsequent to a C2-C3 laminectomy. The patient experienced clinical improvement with a regression of all of her neurological symptoms. Histological findings confirm the diagnosis of beta2m amyloid deposition. However, 5 years after surgery the subcondylian bone cysts were still observed and atlanto-occipital instability required her to wear a minerva. CONCLUSION: Our case report confirms that surgical excision of beta2m epidural deposits is necessary and relevant when neurological prognosis is discussed, and that pain is still the major symptom of disease evolution. The use of high-flux synthetic membranes could decrease the beta2m blood level and early renal graft is the only method to prevent such complications.

Amyloidosis↗

PubMed2006

[Facial paralysis after temporal bone trauma].

OBJECTIVES: To evaluate functional outcome in 64 cases of facial paralysis following temporal bone fracture and discuss decisive arguments leading either to medical treatment or surgical management. METHODS: Sixty-four patients suffering from post-traumatic facial paralysis were managed between 1995 and 2003: 38 (59%) were given medical treatment and 26 (41%) underwent surgery. A combined middle fossa and transmastoid approach was mostly used (58%). Electrophysiological testing and CT scan results were the main points of the decision algorithm. RESULTS: Electroneuromyography seems to be the most accurate exploration for guiding treatment. Good results (grades I to II on the House and Brackmann scale) were obtained in 63% of cases after medical management and in 39% of cases after surgical treatment. Grades III or IV were obtained in 13% of medically-treated patients and 42% of surgically-treated patients. CONCLUSION: Management of facial paralysis following temporal bone fracture in accordance with electrophysiological testing (evoked EMG) together with CT scan findings enabled accurate indications for surgical treatment. A good grade I or II result can be expected after medical management. A grade III is at best reached after nerve anastomosis.

Adolescent↗

PubMed2006

[Side-to-end hypoglossal-facial nerve anastomosis with intratemporal facial nerve translocation. Long-term results and indications in 15 cases over 10 years].

OBJECTIVES: To describe functional results concerning facial and lingual mobility after side-to end hypoglossal facial nerve anastomosis. MATERIAL AND METHODS: 15 patients were operated on between 1993 and 2002 (11 cases of facial nerve injury during vestibular schwannoma surgery, and 4 cases of brainstem stroke). Were assessed at a minimum of 18 months postop tonus and facial voluntary movements recovery (modified House Brackmann (HB) grading), lingual mobility (amyotrophy and self-evaluation questionnaire), and patients' overall satisfaction (questionnaire). RESULTS: The mean delay to evaluation was 57.5 months. The tonus recovery appeared within 6 to 8 months (mean 28.5 weeks, SD 4.6 weeks). All patients recovered a normal tonus. The facial function was evaluated HB grade III in II cases (73.3%), grade IV in 3 cases (20%) and grade V in one (6.6%). Eye occlusion was obtained within 13.6 months on average (SD 2.6 months) in all cases except one. The blepharorraphy was maintained in 2 patients. No facial spasm was noted. The lingual motricity troubles were absent in 93.3% of cases. Patients were satisfied in 93.3% of cases. The less satisfactory results were observed when patients were managed late (>2 years after nerve section) and in case of brainstem stroke. CONCLUSION: This technique seems to be very efficient. It presents the advantage to preserve lingual motricity and to decrease postoperative problems of midface spasticity.

Adult↗

PubMed2005

[Management of cerebellopontine angle meningiomas and the posterior part of the temporal bone. Report on 44 cases].

OBJECTIVES: To review and study the management of CPA meningiomas through the experience of an otoneurosurgical team. MATERIAL AND METHODS: Fourty-two patients (44 meningiomas) were considered. Seventy-seven per cent of tumors (34 cases) were operated on; 6 tumors (14.6%) were exclusively irradiated using fractionated radiation therapy (FRT) and four only surveyed (9,8%). RESULTS: transpetrosal approaches were exclusively used. These were translabyrinthine (TLA) in 47%, widened retrolabyrinthine (WRLA) in 41% of cases, transcochlear approach (TCA) in three cases and a middle fossa in one. A transtentorial approach was combined in 35% of cases (8 TLA, 4 WRLA). Surgical removal was incomplete in 11,8% of cases; in 3 cases growing tumor was treated by FRT included one case of anaplasic tumor Postoperative complications were: 1 meningitis, 1 wound abscess, 2 hydrocephalus (6%) and 4 CSF fistulas (12%). No complications have been observed during the last 7 years (21 cases). House and Brackmann Grade 1 or 2 facial function was obtained in 59% of cases (but 10 patients had a preoperative facial nerve paresis). A normal or subnormal AAO-HNS Class A-B Hearing could be preserved in 57% of WRLA. Radiation therapy allowed tumor shrinkage in all cases. In 3 cases this regression was of more than 50%. CONCLUSION: Surgery is the gold standard in treating CPA meningiomas. Transpetrosal approaches and particularly WRLA pure or combined to a transtentorial approach are for us the best way to remove these tumors in preserving hearing and facial nerve function. When hearing is poor or when tumor extension to the clivus or the premeatal area is consistent a TLA is either planned preoperatively or obtained from a WRLA.

Adult↗

PubMed2001

[Gross tumor volume (GTV) and clinical target volume (CTV) in radiotherapy of benign skull base tumors].

Skull base tumours represent about 35 to 40% of all intracranial tumours. There are now many reports in the literature confirming the fact that about 80 to 90% of such tumours are controlled with fractionated radiotherapy. Stereotactic and 3-dimensional treatment planning techniques increase local control and central nervous system tolerance. Definition of the gross tumor volume (GTV) is generally easy with currently available medical imaging systems and computers for 3-dimensional dosimetry. The definition of the clinical target volume (CTV) is more difficult to appreciate; it is defined from the CTV plus a margin, which depends on the histology and anterior therapeutic history of the tumour. It is important to take into account the visible tumour and its possible extension pathways (adjacent bone, holes at the base of skull) and/or an anatomic region (sella turcica + adjacent cavernous sinus). It is necessary to evaluate these volumes with CT Scan and MRI to appreciate tumor extension in a 3-dimentional approach, in order to reduce the risk of marginal recurrences. The aim of this paper is to discuss volume definition as a function of tumour site and tumour type to be irradiated.

Humans↗

PubMed2001

Management of facial paralysis resulting from temporal bone fractures: Our experience in 115 cases.

OBJECTIVE: The goal of this study was to review decision factors and overall results regarding surgical and nonsurgical management of post-traumatic facial nerve paralysis (FP). STUDY DESIGN: A retrospective study and literature review were performed. METHODS: Between 1984 and 1990, 115 cases of post-traumatic FP were handled. Patients were evaluated through clinical, audiologic, radiologic, and electromyogram assessment. Depending on examination results, patients were treated either medically or surgically through total facial nerve decompression. RESULTS: Forty-nine of the 50 medically treated patients experienced a normal or subnormal facial function recovery (grade I-II). Of the 65 (56.5%) surgically treated patients, 52 (80%) had immediate, 2 had delayed, and 11 (17%) had unknown delay-associated FP. The approaches chosen were middle fossa and transmastoid (75.3%), translabyrinthine (10.7%), or pure transmastoid according to facial nerve nonmotor branch evaluation, hearing, location of the fracture line, and the patient's general condition. Lesions were predominantly found in the geniculate ganglion area (66.2%). A nerve gap was found in only 13.8% of the cases. At 2 years after surgery, 93.8% had a grade I to III recovery. None had grade V or VI. CONCLUSION: The rarity of severe nerve lesions encountered in surgically treated patients raises the question of better selection of candidates for surgery. Surgery is clearly indicated when FP is total, is of immediate onset, and is associated with a bad prognosis electromyogram pattern. In other settings, decisions are to be made based on high-resolution CT data and electromyogram results, thanks to a clinical survey and second electromyogram evaluation.

Adolescent↗

PubMed2001

Dorsal rhizotomy with anterior sacral root stimulation for neurogenic bladder.

A spinal cord lesion above the sacral micturition center results in a loss of voluntary control and development of bladder sphincter dysynergia with hyperreflexia of the detrusor and spasticity of the sphincter. Sacral rhizotomy and implantation of an anterior sacral root stimulator appears as an effective method for the treatment not only of voiding dysfunction but also of defecation and sexual disturbance. The surgical technique is described as are the clinical and electrophysiological controls. The results of our series of operated patients with intradural implantation and sacral deaffentation show a constant improvement. 90% have satisfactory continence and no longer require an incontinence appliance. Bladder capacity and compliance have increased to 120% and urethral closure pressure has decreased. 80% have complete voiding or a post-void residue of not more than 50 ml. So, urinary infection rate is dramatically decreased.

Humans↗

PubMed2000

The rat asialoglycoprotein receptor binds the amino-terminal domain of thyroglobulin.

We have previously reported that the rat hepatic lectin-1 (RHL-1) subunit of rat asialoglycoprotein receptor (ASGPr), the endocytic receptor found on the basolateral surface of hepatocytes, was expressed in rat thyroid tissue and localized on the apical surface of polarized rat thyroid FRT cells. Here we show that PC Cl3 cells, a differentiated rat thyroid cell line, bound thyroglobulin (Tg) via ASGPr. In fact, both the bacterial recombinant carbohydrate recognition domain of RHL-1 (rCRD(RHL-1)) and the anti-rCRD(RHL-1) antibody markedly inhibited (125)I-Tg binding to the cell surface of PC Cl3 cells. Ligand blot assays with deglycosylated Tg show that the rCRD(RHL-1) was able to interact with Tg even after remotion of sugars. The region of Tg involved in the binding to RHL-1 was investigated by ligand blot assays with biotinylated rCRD(RHL-1) on thermolysin-digested native and desialated rat thyroglobulin. It is shown that the rCRD(RHL-1) specifically recognized a thyroglobulin fragment with an apparent M(r) of 68,000, corresponding to the amino-terminal part of the molecule. To our knowledge, this is the first report that attributes to the amino-terminal portion of Tg molecule, containing its earliest and major hormonogenic site, the function of binding to a cell surface receptor of the thyroid. Moreover, we show that oligosaccharides are not the only molecular signals for binding to RHL-1, but amino acidic determinants could also play a role.

Amino Acid Sequence↗

PubMed2000

The rat hepatic lectin-1 subunit of the asialoglycoprotein receptor is upregulated by thyrotropin and downregulated by neoplastic transformation of thyroid cells.

We have recently shown that the rat hepatic lectin (RHL)-1 subunit of the asialoglycoprotein receptor (ASGPr) is expressed in the PC C13 differentiated thyroid cell line. To investigate in vivo the expression of RHL-1 and the ability of thyrotropin (TSH) to modulate its expression, reverse-transcriptase polymerase chain reaction (RT-PCR) and Western blot assays have been performed on thyroid extracts from rats treated with thyroxine (T4) or propylthiouracil (PTU), each of which modulates TSH levels. It is shown that RHL-1 expression is down-regulated by T4 (which decreases serum TSH) and upregulated by PTU (which increases serum TSH), at both mRNA and protein levels. The sensitivity of RHL-1 to neoplastic transformation of thyroid cells has been investigated. The RHL-1 expression pattern has been studied in PC C13 thyroid cells transformed by several oncogenes that induce different degrees of malignancy and dedifferentiation. RT-PCR and Western blot assays show that RHL-1 expression progressively decreases as PC C13 cells acquire a more transformed phenotype. Expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA, a housekeeping gene used as internal control to normalize RHL-1 mRNA content, exhibits no variations in the different PC C13 cell lines used. In addition, we show that both native and asialo-thyroglobulin (Tg) bind RHL-1 in vitro, and native Tg binds RHL-1 on the surface of PC C13 cells. After thyroid cells transformation, the surface expression of RHL-1 is inhibited in a measure that correlates with the mRNA and protein levels. Therefore, the RHL-1 inhibition at the mRNA, protein and plasma membrane expression follows a gradient that parallels the progressive acquisition of the fully transformed phenotype in the PC C13 system. The results reported in the present article, together with our previous data, suggest that RHL-1 expression could be regulated, at least in part, by the same transcription factors involved in the expression of the other molecules characteristic of the thyroid differentiated state.

Animals↗

PubMed1999

Thyroglobulin binding and TSH regulation of the RHL-1 subunit of the asialoglycoprotein receptor in rat thyroid.

The ability of asialo-thyroglobulin to bind the thyroid RHL-1 subunit of the asialoglycoprotein receptor has been investigated. Ligand blot assays show that the recombinant carbohydrate recognition domain of the thyroid RHL-1 subunit specifically interacts with rat desialated thyroglobulin. Moreover, RT-PCR and Western blot assays show that TSH deprivation decreases RHL-1 expression in PC C13 thyroid differentiated cells whereas insulin deprivation does not have any effect. The simultaneous absence of both TSH and insulin dramatically decreases the level of RHL-1 expression.

Animals↗

PubMed1999

The posterior sacral foramina: an anatomical study.

The vascular and nervous structures and their relations with the spinal nerve roots were examined in the 2nd, 3rd and 4th posterior sacral foramina in relation to percutaneous needle insertion for neuromodulation. A foraminal branch provided by the lateral sacral artery to each foramen entered the inferior lateral quadrant of each foramen, adjacent to the nerve root medially. Facing the posterior sacral aperture and around the sacral nerves, there was no venous plexus. A venous plexus was sometimes present near the median line, and always around the proximal part of the spinal ganglion. The sacral nerve roots, especially the 3rd, had a long extradural course in the foramen, presenting a potential risk of nerve lesions during procedures involving needle insertion.

Aged↗

PubMed1999

[Intramuscular myxoma. A case of myxoma of the spinal erector muscle].

A case of intramuscular myxoma, extended in the lumbar erector spinae muscles, is reported. This soft tissue tumor is rare, about one hundred observations are indexed in the literature. The clinical findings are nonspecific, magnetic resonance imaging reveals few characteristics, and finally a histological examination is required, after surgical removal, to pinpoint the diagnosis. Recurrence is uncommon, but a systematic follow-up is necessary.

Female↗

PubMed1998

Morphologic and histologic study of the ligamentum flavum in the thoraco-lumbar region.

The ligamentum flavum, of which there are only a few studies in the literature, has several features discussed in this work. On the macroscopic level, it has a metameric arrangement: it has two layers, superficial and deep, whose fibers are opposite, and it has close relations with the tendons of attachment of some spinal erector muscles. On the microscopic level, its structure is unique for a ligament, because of a predominance of elastic fibers, because of its intrinsic innervation at each level of the spine, and because this innervation grows poorer with increasing degeneration. The ligamentum flavum constitutes an active ligament, with an essential biomechanical role. Its injury is probably not without consequences, and therefore there are many technical problems about the surgical interlaminar approach.

Aged↗

PubMed1998

Inhibition by glass-ionomer cements of protein synthesis by human gingival fibroblasts in continuous culture.

The effects of several glass-ionomer cements (Baseline and Chem Fil of De Trey; Ketac Fil and Ketac Bond of ESPE; Vitrebond and Vitremer of 3 M) on the protein synthesis of cultured gingival fibroblasts were studied. The presence of cements in the culture medium inhibited protein synthesis, although the relative effectiveness varied significantly. The cements tested have been ranked in three groups, group A (Chem Fil and Ketac Fil), group B (Ketac Bond and Baseline) and group C (Vitrebond and Vitremer), showing 50, 75 and 100% reduction in protein synthesis, respectively. Incubation of cells with medium previously conditioned by Baseline and Ketac Fil caused only transient inhibition of protein synthesis followed by almost complete recovery. This recovery was not observed when the medium was conditioned with Vitrebond. A characterization of the factors determining the inhibitory effect of one cement in each group was attempted. The cements, irrespective of the type, produced small but reproducible decreases in the pH of the medium but released fluoride ions to a different extent. Both changes in the pH of the medium and in the fluoride concentration inhibited protein synthesis by cultured gingival fibroblasts. The different action of cements can be explained, at least in part, by a differing release of fluoride ions.

Aluminum Silicates↗

PubMed1998

[Oculomotor paralysis and head trauma].

Few studies have dealt with post-trauma ocular motor palsy. We analyzed 31 personal cases and reviewed the literature, focusing on pathogenesis. We emphasize the importance of a complete radiological examination including magnetic resonance imaging when the CT-scan does not provide a satisfactory correlation between anatomic findings and clinical presentation. Systematic detection, early management and regular follow-up is mandatory.

Adolescent↗

PubMed1995

Inhibition of c-ras reactivates thyroglobulin synthesis in middle-T transformed thyroid cells.

Differentiated thyroid cells expressing polyoma Middle-T became transformed and tumorigenic when injected into syngenic animals. The expression of thyroglobulin was greatly reduced and no longer responsive to thyrotropin (TSH) and to cAMP. Inhibition of endogenous c-ras by the expression of two transdominant negative mutant H-ras genes, Asn17 and Leu61-Ser186, reactivated thyroglobulin synthesis. Reactivation of thyroglobulin synthesis by c-ras inhibition was not observed in the absence of TSH. These findings indicate that MT elicits dedifferentiation of thyroid cells by activating endogenous c-ras and that c-ras interferes with TSH or cAMP signaling.

Animals↗

PubMed1994

Presence of dityrosine bridges in thyroglobulin and their relationship with iodination.

The presence of dimeric thyroglobulin (19S), after reduction and alkylation, suggests that within thyroglobulin there may be intermolecular cross-links, other than disulphide bridges. However, the nature of these intermolecular cross-links is still unknown. In this study, we show the presence of 3-3' dityrosine bridges in the molecule of bovine thyroglobulin by NMR and fluorescence studies. Also, we evaluated the role of iodination in dityrosine formation in vivo and in vitro.

Animals↗

PubMed1994

Dimensions of cervical vertebral bodies according to age and sex.

A biometric comparative roentgenological study of the cervical vertebral bodies was performed, according to age and sex, from lateral roentgenograms of 120 adult cervical regions. The sexual dimorphism already described by many authors was confirmed. The vertebral bodies of C2, C3, and C7 have the more variable structure according to age. The results of our measurements are in accordance with clinical findings and provide data on the structural changes of the cervical spine during ageing. In anthropological terms, the vertebral body of C2, in particular its antero-posterior diameter, is the best age indicator, irrespective of individual and exterior variables.

Adult↗