Search PubMed⌕ Search

Biomedical subjects

S Hussein

Publications and source records attributed to S Hussein.

At least 19 recordsLinked to original sources
PubMed2005

[PMMA pulmonary embolism and post interventional associated fractures after percutaneous vertebroplasty].

A 78-year old woman with osteoporotic collapse of the Th12 and L4 vertebrae was treated by percutaneous vertebroplasty (pVp) with PMMA (polymethylmethacrylate). Postoperatively, the Th11 and L1 vertebrae collapsed so that a second vertebroplasty was performed. Postoperatively, the patient developed a severe pulmonary embolism which was treated conservatively. In this report, the complications of pulmonary embolism, perivertebral leakage of PMMA and of additional vertebral collapses after pVp are discussed.

Aged↗
PubMed2003

Conjoined lumbosacral nerve roots: current aspects of diagnosis.

Conjoined lumbosacral nerve roots (CLNR) are the most common anomalies involving the lumbar nerve structures which can be one of the origins of failed back syndromes. They can cause sciatica even without the presence of a additional compressive impingement (such as disc herniation, spondylolisthesis or lateral recess stenosis), and often congenital lumbosacral spine anomalies (such as bony defects) are present at the "conjoined sheaths". This congenital anomaly has been reported in 14% of cadaver studies, but myelographic or computed tomographic studies have revealed an incidence of approximately 4% only. Diagnostic methods such as magnetic resonance imaging (MRI) are helpful for determination of the exact anatomical relations in this context. We present five typical cases of conjoined nerve roots observed during a 1 year period, equivalent to 6% of our out-patients without a history of surgical treatment on the lumbar spine. In all cases with suspicious radiological findings MRI or lumbar myelography combined with CT and multiplanar reconstructions is recommended.

Adolescent↗
PubMed2002

Continuous intraventricular clonidine infusion in controlled morphine withdrawal--case report.

A patient with atypical bilateral facial pain reported the loss of analgesic effect of intracerebroventricular morphine delivered continuously via an implanted pump, accompanied by intolerable adverse side effects associated with the administered high dose of morphine. Clonidine was substituted for morphine over a period of 3 weeks to achieve a drug holiday. The patient did not have significant withdrawal symptoms or major discomfort from pain, leading to a reduced quality of life during this period. Six months after the treatment, the patient continues to require a significantly lower daily dose of morphine. Morphine withdrawal with clonidine substitution produced a significant improvement in the analgesic efficacy of morphine and in the quality of life in the absence of undesirable side effects.

Analgesics↗
PubMed2001

Arterial supply of the temporo-medial region of the brain: significance for preoperative vascular occlusion testing.

The mesiobasal limbic system is of particular significance in the surgical treatment of temporo-medial tumors and epilepsy. It consists of the uncus, amygdaloid body, hippocampus, dentate gyrus, subiculum, fasciolar gyrus and the parahippocampal gyrus. Knowledge of the vascular microanatomy is a key to the surgical treatment of pathologies in the region. The anterior choroidal artery was selectively injected in fresh brain specimens: 50 specimens with a gelatinous ink mixture to demonstrate vascular territories in stereotactic brain slices, and 50 with a Biodur resin to obtain casts for microanatomical evaluation. The cast technique was also applied to 35 specimens injected into the posterior cerebral artery. The rostral third of the temporomedial region is mainly supplied by branches of the anterior choroidal artery. The occipital two thirds are supplied by hippocampal branches, the posteromedial choroidal artery and the inferior temporal branches of the posterior cerebral artery. Important vessel variations with significant implications for the preoperative Wada-test are presented.

Anterior Cerebral Artery↗
PubMed2001

Identification of inhibitors of heparin-growth factor interactions from combinatorial libraries of four-component condensation reactions.

Chemical libraries based on four-component condensation (4CC) reactions of isocyanides were constructed to identify compounds capable of blocking heparin binding to vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). The reaction products in the synthesized libraries contain heparin mimetic functional groups such as carbohydrates, sulfonates, carboxylates, and hydroxy groups. These libraries have been screened for the inhibition of heparin binding to growth factors such as VEGF and bFGF. Single point screening at 5.0 microM of the 18,720 reaction products generated 26 candidates. The IC50S of these 26 compounds were determined using HPLC-purified products and 20 of the 26 showed significant inhibition of heparin binding to VEGF and/or bFGF. Eighteen of the 20 confirmed active compounds have a linear extended structure. Structures identified in this library revealed an initial relationship of structure and activity, thus providing direction for further investigation of this type of heparin mimetic libraries.

Chromatography, High Pressure Liquid↗
PubMed2001

Effect of vincristine on gastric motility in conscious rats.

We investigated the possible involvement of the upper alimentary tract in vincristine (VCR)-induced dysmotility. Gastric contractions were recorded by a strain-gauge force transducer in conscious rats. Rats were injected with various doses of VCR followed by continuous recording for 12 hr. Additionally, 3-hr recordings to study the later effects were performed one and three days after injection. Gastric motility was dose-dependently increased by VCR. Post- versus preinjection motility index (MI; area under contraction waves) ratios were 0.78+/-0.12 for saline and 1.95+/-0.21 for VCR at 0.75 mg/kg. This increase in MI was completely inhibited by atropine and hexamethonium. MI one day after injection of VCR (0.75 mg/kg) was significantly less than in control (0.32+/-0.10 vs 0.92+/-0.24, respectively). The decrease was reversed by acetylcholine. In conclusion, VCR first increased gastric motility, and this was followed by a gradual decrease in conscious rats. These alterations may involve a presynaptic cholinergic pathway.

Acetylcholine↗
PubMed2001

[Computer assisted plastic closure of calvarial defects].

Large bony skull defects sometimes face problems of some pathophysiological effects, protection of the underlying brain, the impaired appearance, and from a psychological point of view. A computer-assisted method is presented, which has been successfully used in 44 patients. From 3-D-CT data a phantom was built in which Refobacin-Palacos was modeled for individual requirements. The plastic can be implanted after sterilization and leads to excellent cosmetical results. The use of a negative model reveals the possibility of an extended field of application without the necessity of highly specialized computersystems.

Adolescent↗
PubMed2000

[Initiation of rehabilitation after surgery for herniated lumbar disk: pilot study of efficacy from the viewpoint of the surgical hospital].

The initiation of rehabilitation after lumbar disc surgery in Germany is up to the operating hospital. A decision between outpatient and inpatient rehabilitation is possible. Until now this decision is not based on scientific data but on the individual experience of the hospital. This prospective study compares the effect of outpatient and inpatient therapy: In 65 patients medical and psychosocial data were collected shortly before operation, 1 week and 6 months after surgery. Of these patients, 42 underwent inpatient, 21 outpatient rehabilitation, 2 patients renounced rehabilitation. The outpatient and inpatient rehabilitation groups showed no significant difference in testing before or shortly after the operation concerning subjective state of health and somatic findings. Some 6 months later, long term outcome was identical, i.e. the groups did not differ in psychosocial or medical respects. However, the inpatient rehabilitation group had taken significantly longer to return to work. This pilot study stresses the importance of further research on rehabilitation after lumbar disc surgery. It should be shared by surgeons and rehabilitation experts.

Adult↗
PubMed2000

Minimal invasive decompression of the orbit in Graves' orbitopathy.

BACKGROUND: Surgical decompresssion of the orbit may be considered as a suitable form of therapy if, as a result of the increased volume inside the orbit, there are motility disorders such as diplopia or a progressive decrease in visual acuity. In view of the fact that this operation will not cure the underlying disease, the treatment should be as mild as possible. METHODS: In five subjects with Graves' orbitopathy we managed to extend the volume of the intraconal orbit by microsurgical liposuction. We carried out a lateral canthotomy to approach the orbit behind the globe. After decompression of the soft tissue, the lateral palpebral ligaments were refixed. To assess the scale of the functional rehabilitation we compared preoperative parameters (visual acuity, Hertel's index, visual field, motility) with the postoperative results. RESULTS: In all cases we found a significant improvement of position and motility without signs of diplopia. There was a postoperative increase in the visual field and visual acuity was 0.4 and the protusion of the globe could be decreased by 3-6 mm (Hertel's index). Furthermore, the ocular hypertension we found preoperatively could no longer be detected after the operation. CONCLUSIONS: Microsurgical decompression of the soft tissue via an approach from behind the globe proved to be a very gentle alternative to conventional methods of orbital decompression because of the satisfying functional and esthetic rehabilitation in selected cases.

Adult↗
PubMed2000

No implicit memory for stories played during isoflurane/alfentanil/nitrous oxide anesthesia: a reading speed measurement.

UNLABELLED: Implicit memory of intraoperatively presented stories was recently detected by using the reading speed paradigm during propofol-alfentanil-nitrous oxide anesthesia. Our main goal was to evaluate the reading speed test procedure under another anesthetic regimen, i.e., isoflurane combined with nitrous oxide and alfentanil-infusion. In both experiments, patients were premedicated with oral midazolam. In a previous experiment, patients postoperatively read "old" stories that had been presented during anesthesia quicker compared with "new," unpresented stories. The same study design and test material as in the previous experiment were used. One of two audio tapes with two short stories was played randomly to patients during lumbar disk surgery and to awake controls. Approximately 7 h later, a structured interview and the reading speed test were used to determine whether the participants had any explicit or implicit memories of the presented stories. The results of 30 patients and 30 controls were calculated. Whereas the control participants showed an intact explicit and implicit memory of the previously presented material, no such effect was found in the anesthetized patients. The present experiment shows that changing the main anesthetic in otherwise equal study conditions, i. e., propofol to isoflurane (end-expiratory 0.7%), implicit memory is abolished in anesthetized patients. IMPLICATIONS: We showed that implicit memory during general anesthesia can be abolished by changing the hypnotic anesthetic. Increased postoperative reading speed for stories presented during propofol-alfentanil-nitrous oxide anesthesia was shown in a previous experiment, but not in our study using isoflurane for balanced anesthesia.

Adult↗
PubMed2000

Massive rise in thyroglobulin with adult respiratory distress syndrome after embolisation of thyroid cancer metastasis.

A patient with long-standing metastatic disease from a well differentiated papillary cell carcinoma of the thyroid underwent embolisation of a painful large sacral metastasis. Following embolisation she had a massive rise in circulating serum thyroglobulin (Tg) levels coinciding with the development of adult respiratory distress syndrome (ARDS) on the tenth day without any other obvious cause. The patient subsequently recovered. The time course suggests that ARDS in this case might have resulted from aggregation of Tg molecules in the pulmonary microcirculation.

Carcinoma, Papillary↗
PubMed2000

Disruption of intracerebral progression of C6 rat glioblastoma by in vivo treatment with anti-CD44 monoclonal antibody.

OBJECT: Glioblastoma multiforme (GBM) invasiveness is a complex process that involves recognition and attachment of GBM cells to particular extracellular matrix (ECM) molecules before migrating into proteolytically modified matrix and inducing angiogenesis. The CD44 molecule, which is a transmembrane adhesion molecule found on a wide variety of cells including GBM, has been suggested as the principal mediator of migration and invasion. The aim of the present study was to demonstrate whether an antibody specific to the standard form of CD44 (CD44s, 85-90 kD) might prevent invasion and thus disrupt progression of C6 GBM in vivo. METHODS: Immunostaining demonstrated homogeneous expression of CD44s on the surface of C6 GBM cells and tumors. Flow cytometric analysis demonstrated binding saturation of anti-CD44s monoclonal antibody (mAb) to the receptor at 1 microg/5 x 10(5) cells. Blocking of CD44s in vitro resulted in a dose-dependent progressive (up to 94+/-2.7%; mean +/- standard deviation [SD]) detachment of C6 cells from ECM-coated culture. Blocking of CD44s in vivo resulted in significantly reduced C6 brain tumors (3.6+/-0.4% [SD])--measured as the quotient: tumor surface (mm2)/brain surface (mm2) x 100--compared with untreated (19.9+/-0.9%) or sham-treated (19.2+/-1.1 to 19.3+/-2.5% [SD]) rats. Disruption of C6 GBM progression correlated with an improved food intake; treated rats were significantly less cachectic (166.6+/-16.4 g [SD]) than those that were untreated (83+/-2.7 g [SD]) or sham-treated (83.4+/-1.1 to 83+/-2.2 g [SD]) rats. CONCLUSIONS: The authors conclude that CD44s-targeted treatment with specific mAb may represent an effective means for preventing progression of highly invasive GBMs.

Animals↗
PubMed2000

Congenital arthrogryposis associated with atlantoaxial subluxation and dysraphic abnormalities. Case report.

The authors report the case of a 27-year-old woman with an arthrogryposis multiplex congenita (AMC) associated with atlantoaxial subluxation. To the authors' knowledge, this is the first report of its kind. The authors review the literature with reference to dysraphic abnormalities associated with atlantoaxial subluxation and with AMC. The patient presented with severe tetraparesis following a minor traffic accident. She underwent a procedure in which transoral decompression and dorsal stabilization were performed and, postoperatively, made a good clinical outcome. The authors stress the need for diagnostic neuroimaging of the craniocervical junction in patients with AMC.

Accidents, Traffic↗
PubMed1999

Lung compensator design using an electronic portal imaging device.

Using a liquid filled electronic portal imaging device (EPID) installed on a linear accelerator and a composite chest phantom, exit dose measurements were carried out to establish an empirical relationship between the pixel values of the imaging detector and the corresponding equivalent thickness of the overlying phantom material. Results for 6 and 10 MV photons show that the relationship depends on the so-called input/output characteristics of the imaging device for a particular photon energy. For a chest irradiation, an EPID image obtained under treatment geometry provides the pixel value information that is used to calculate the tissue deficit over the lung region. The compensators are made of lead whose thickness is calculated from the established empirical relationship to replace the tissue deficit over lungs. The effectiveness of the method is demonstrated with thermoluminescent dosimetry (TLD) for 6 and 10 MV beams. With compensators in place, the dose uniformity was found to be within +/- 5%.

Humans↗
PubMed1999

CD44s-targeted treatment with monoclonal antibody blocks intracerebral invasion and growth of 9L gliosarcoma.

Glioma invasiveness is a complex process involving recognition and attachment of tumor cells to particular extracellular matrix (ECM) molecules prior to migrating into proteolytically modified matrix and inducing angiogenesis. CD44 is a group of transmembrane adhesion molecules found on a wide variety of cells including gliomas that has been suggested as the principal mediator of migration/invasion. The aim of the present study was to demonstrate whether antibody specific for the standard form of CD44 (CD44s, 85-90 kDa) might prevent invasion, thus blocking growth of the 9L gliosarcoma in vivo. High expression of CD44s on the surface of 9L cells and brain tumors was demonstrated by immunochemistry. Fluorescence-activated cell sorting (FACS) demonstrated binding saturation of anti-CD44s monoclonal antibody (mAb) to the receptor at 1 microg/5 x 10(5) cells. Blocking of CD44s in vitro resulted in a dose-dependent progressive, up to 95%+/-2.5% detachment of 9L cells from ECM-coated culture surfaces. Blocking of CD44s in vivo resulted in significantly reduced 9L brain tumors (2.5%+/-0.4%)--measured as the quotient: tumor surface (mm2)/brain surface (mm2) x 100--as compared to untreated (16.1%+/-2.2%) or sham-treated rats (16%+/-3.7% to 16.1%+/-3%). We conclude that CD44s-targeted treatment with specific mAb may be an effective means for preventing glioma progression.

Animals↗