bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of “Bonnet” Bypass with Radial Artery Interposition Graft in a Patient with Recurrent Cranial Base Carcinoma: Technical Report of Two Cases and Review of the Literature
Authors: Deshmukh Vivek R. , Porter Randall W. , Spetzler Robert F. 
Published: February 2005

Abstract

OBJECTIVE AND IMPORTANCE:
Two patients with recurrent cranial base carcinomas involving the carotid artery received a “bonnet” bypass using the contralateral superficial temporal artery as the donor vessel because the ipsilateral common and external carotid arteries were unavailable. The radial artery was used as the graft.

CLINICAL PRESENTATION:
A 58-year-old man with ear pain and an enlarging mass involving the left cranial base and neck had undergone a right partial glossectomy and modified neck dissection followed by radiotherapy for squamous cell carcinoma. Recurrent carcinoma extensively involved the left internal carotid artery. A 46-year-old man with jaw pain and hoarseness had undergone multiple resections and radiation therapy for medullary thyroid carcinoma. Magnetic resonance imaging showed recurrent tumor on the right.

INTERVENTION:
Both patients underwent a pterional craniotomy. The supraclinoid internal carotid artery was exposed. The radial artery was harvested. The contralateral superficial temporal artery was dissected at its bifurcation into the frontal and parietal branches. The radial artery graft was anastomosed to the superficial temporal artery and a recipient ipsilateral branch of the middle cerebral artery. The internal carotid artery was clip-ligated. After surgery, both patients remained neurologically stable. Angiography confirmed that the bypasses were patent and that the middle cerebral artery territory filled. The patients’ carcinomas were resected aggressively.

CONCLUSION:
When aggressive resection of cranial base tumors is needed and the ipsilateral carotid artery is unavailable as a donor vessel, a “bonnet” bypass with carotid artery sacrifice may be performed. Compared with vein grafts, microsurgical anastomosis is easier and the patency rate is higher with a radial artery graft.
Titanium Cage-assisted Polymethylmethacrylate Reconstruction for Cervical Spinal Metastasis: Technical Note
Authors: Liu James K. , Rosenberg William S. , Schmidt Meic H. 
Published: February 2005

AbstractOBJECTIVE:Reconstruction and stabilization of the cervical spine after vertebrectomy is an important goal in the surgical management of spinal metastasis. The authors describe their reconstruction technique using a titanium cage-Silastic tube construct injected with polymethylmethacrylate (PMMA) augmented by an anterior cervical plate. The surgical results using this technique are reviewed.METHODS:Six patients ranging from 43 to 70 years of age underwent resection of metastatic tumor in the cervical spine followed by cage-assisted PMMA reconstruction of the anterior spinal column. The following reconstruction technique was performed. A Silastic tube is incised longitudinally and placed circumferentially around a titanium cage with the opening facing anteriorly. The cage-Silastic tube construct is carefully tapped into the corpectomy defect and filled with PMMA. The final construct is then augmented with anterior cervical plate fixation.RESULTS:Two patients required additional posterior stabilization with lateral mass screws and rods. All patients achieved immediate stabilization, restoration of vertebral body height and normal lordosis, and preservation of the ability to walk independently. Five patients experienced significant palliation of biomechanical neck pain. There were no complications of neurological worsening, postoperative hematoma, wound infection, subsidence, graft dislodgement, or construct failure during a follow-up period of 1 to 19 months (mean, 6.8 mo).CONCLUSION:Titanium cage-assisted PMMA reconstruction augmented with an anterior cervical plate is an effective means of reconstruction after tumor resection in patients with cervical spinal metastasis. The Silastic tube holds the PMMA within the cage and protects the spinal cord from potential thermal injury.
Lateral Ventricle Tumors: Surgical Strategies According to Tumor Origin and Development— A Series of 72 Cases
Authors: D'Angelo Vincenzo A. , Galarza Marcelo , Catapano Domenico , Monte Vincenzo , Bisceglia Michele , Carosi Illuminato 
Published: February 2005

Abstract

OBJECTIVE:
Optimal surgical management in lateral ventricle tumors remains controversial. We conducted a retrospective study of patients with these lesions treated with a surgical strategy on the basis of tumor origin: primary or secondary ventricular and associated transependymal development.

METHODS:
A total of 72 patients underwent surgery for lateral ventricle tumors. The mean patient age was 39 years (range, 6 mo to 78 yr). Raised intracranial pressure occurred in 53% of patients, followed by mental disturbances or psychiatric symptoms (32%) and motor deficits (21%). The transcortical approach was used in 44 patients, and an interhemispheric approach was used in 28 patients; a transcallosal approach was used in 16 patients, and a parasplenial approach was used in 12 patients. Neuropsychological tests were performed in selected patients.

RESULTS:
Total resection was performed in 82% of patients. Sixty-five percent of tumors were benign and low-grade tumors. There was no surgical mortality, and the morbidity rate was 11%. Postoperative epilepsy (5.9%) was significantly increased in the transcortical group. The mean follow-up period was 55 months; 59% of patients achieved good recovery and moderate disability. In postoperative neuropsychological testing sessions, deficits in verbal memory were observed in six patients (8%). Final morbidity correlated well with preoperative clinical condition and pathological diagnosis.

CONCLUSION:
Lateral ventricle tumors can be treated best by careful selection of the approach according to tumor origin and development. Overall, the transcallosal approach is preferred, but in patients with transependymal growth or large primary or secondary ventricular tumors, the transcortical is a better option.
Biomechanical Comparison of Two Stabilization Techniques of the Atlantoaxial Joints: Transarticular Screw Fixation versus Screw and Rod Fixation
Authors: Kuroki Hiroshi , Rengachary Setti S. , Goel Vijay K. , Holekamp Scott A. , Pitkänen Ville , Ebraheim Nabil A. 
Published: February 2005

AbstractOBJECTIVE:To compare the biomechanical stability imparted to the C1 and C2 vertebrae by either transarticular screw fixation (TSF) or screw and rod fixation (SRF) techniques in a cadaver model.METHODS:Ten fresh ligamentous human cervical spine specimens were harvested from cadavers. The specimens were tested sequentially in the intact state, after injury and stabilization (unilateral left side and bilateral), and after fatiguing to 5000 cycles (0.5 Hz) at ±1.0 N·m of flexion and extension. The specimens were stabilized by use of TSF in 5 spines or SRF in the other 5 spines. The data were converted to angular displacements, and the stabilized cases were compared with intact states for evaluating the efficacies of the two techniques in stabilizing the C1–C2 segments.RESULTS:In the TSF group, the unilateral fixation using one screw imparted a significant stability in only the axial rotation mode. The unilateral procedure in the SRF group was effective in stabilization in all modes except in extension. The bilateral procedure in both of the groups was effective across the C1–C2 segment. However, the SRF group afforded higher stability than the corresponding TSF group in the flexion and extension modes. The degree of stability did not change after fatigue compared with the prefatigue data.CONCLUSION:In general, a surgeon should undertake a bilateral fixation to achieve sufficient stability across the atlantoaxial complex, and either technique will provide satisfactory results, although the SRF technique may be better in the flexion and extension modes. One should use the SRF procedure while trying to achieve stability with a unilateral system.
Bulbar Compression by an Ectatic Vertebral Artery: A Novel Neurovascular Construct Relieved by Microsurgical Decompression
Authors: Tomasello Francesco , Alafaci Concetta , Salpietro Francesco M. , Longo Marcello 
Published: February 2005

Abstract

OBJECTIVE:
Brainstem compression caused by vascular abnormalities has rarely been reported in the literature. We describe five cases of large ectatic vertebral artery causing compression and distortion of the medulla oblongata with pyramidal tract signs and low cranial nerve dysfunction. Microvascular decompression by retracting the vertebral artery and anchoring it to the dura has been the treatment of choice.

METHODS:
Five patients, four male and one female, presented with progressive myelopathic features and lower cranial nerve dysfunction, especially dysphonia and dysphagia. Four patients were affected by systemic arterial hypertension. Magnetic resonance imaging showed impingement of the right vertebral artery in three patients and the left vertebral artery in two patients, on the right and left lateral medulla, respectively. In two patients, hypoplasia of the contralateral vertebral artery was documented.

RESULTS:
All patients underwent neurovascular decompression of the medulla oblongata. The ectatic and tortuous vertebral artery was detached from the medulla, shifted away, and repositioned by anchoring to the nearby dura mater using a Gore-Tex vascular slip. Postoperatively, all patients but one had improvement of their previous neurological symptoms.

CONCLUSION:
Brainstem dysfunction caused by a tortuous ectatic vertebral artery might be less uncommon than expected. It should be considered a new distinct clinical entity, the real incidence of which needs to be carefully evaluated by an appropriate diagnostic protocol, which includes primarily magnetic resonance imaging with specific three-dimensional sequences. Awareness of this condition is necessary to ensure the appropriate treatment. Surgical microvascular decompression seems very effective.
Landmarks for Vertebral Artery Repositioning in Bulbar Compression Syndrome: Anatomic and Microsurgical Nuances
Authors: Grasso Giovanni , Alafaci Concetta , Passalacqua Marcello , Tschabitscher Manfred , Salpietro Francesco M. , Tomasello Francesco 
Published: February 2005

Abstract

OBJECTIVE:
The purpose of this study was to better elucidate the anatomic relationship between the vertebral artery (VA) along with its perforating vessels and the brainstem to develop anatomic guidelines that would be helpful when decompressing medulla oblongata compressed by the VA.

METHODS:
Microanatomy dissection was performed in six formalin-fixed cadaveric heads. The VA, posteroinferior cerebellar artery (PICA), anteroinferior cerebellar artery (AICA), and lower brainstem perforators were examined under magnification using a surgical microscope. The outer diameters of the VA, PICA, and AICA were measured. The distance between the VA, lying within the lateral cerebellomedullary cistern, and the medulla oblongata was quantified. The lower brainstem perforating vessels were examined in relation to their course, outer diameter, and length.

RESULTS:
In four of six brains, the left VA was dominant, presenting an outer diameter at least 0.8 mm larger than the contralateral VA. The average distance between the VA and the medulla oblongata was 3 mm. The perforating branches presented a mean outer diameter of 0.7 mm. In particular, perforators arising from the VA and PICA (Groups 1 and 2) presented an average outer diameter of 0.2 mm and an average length of 7 mm. Perforating vessels arising from the AICA and vertebrobasilar junction (Groups 3 and 4) presented an average outer diameter of 0.4 mm and an average length of 12 mm.

CONCLUSION:
This work provides new information that may be useful to minimize the risk of injury of perforators when operating on medulla oblongata compression by the VA.
Evidence for the use of reflected self-generated seismic waves for spatial orientation in a blind subterranean mammal
Authors: Kimchi Tali , Reshef Moshe , Terkel Joseph 
Published: February 2005

SUMMARY
Subterranean mammals like the blind mole-rat (Rodentia: Spalax ehrenbergi) are functionally blind and possess poor auditory sensitivity,limited to low-frequency sounds. Nevertheless, the mole-rat demonstrates extremely efficient ability to orient spatially. A previous field study has revealed that the mole-rat can assess the location, size and density of an underground obstacle, and accordingly excavates the most efficient bypass tunnel to detour around the obstacles. In the present study we used a multidisciplinary approach to examine the possibility that the mole-rat estimates the location and physical properties of underground obstacles using reflected self-generated seismic waves (seismic `echolocation').
Our field observations revealed that all the monitored mole-rats produced low-frequency seismic waves (250-300 Hz) at intervals of 8±5 s (range:1-13 s) between head drums while digging a bypass to detour an obstacle. Using a computerized simulation model we demonstrated that it is possible for the mole-rat to determine its distance from an obstacle boundary (open ditch or stone) by evaluating the amplitude (intensity) of the seismic wave reflected back to it from the obstacle interface. By evaluating the polarity of the reflected wave the mole-rat could distinguish between air space and solid obstacles. Further, the model showed that the diffracted waves from the obstacle's corners could give the mole-rat precise information on the obstacle size and its relative spatial position.
In a behavioural experiment using a special T-maze setup, we tested whether the mole-rat can perceive seismic waves through the somatosensory system and localize the source. The results revealed that the mole-rat is able to detect low frequency seismic waves using only its paws, and in most cases the mole-rats determined accurately the direction of the vibratory source. In a histological examination of the glabrous skin of the mole-rat's paws we identified lamellate corpuscle mechanoreceptors that might be used to detect low frequency seismic waves.
The combined findings from these different approaches lead us to suggest that a specialized seismic `echolocation' system could be used by subterranean mammals to determine the most energy-conserving strategy with which to bypass an obstacle, as well as to estimate their distance from the surface, keeping their tunnels at the optimal depth.
Host nutrition determines blood nutrient composition and mediates parasite developmental success:Manduca sextaL. parasitized byCotesia congregata(Say)
Authors: Thompson S. N. , Redak R. A. , Wang L.-W. 
Published: February 2005

SUMMARYThis investigation examined the influence of dietary protein and carbohydrate balance in a chemically defined artificial diet for Manduca sexta larvae on development of the gregarious parasite Cotesia congregata. Normal unparasitized larvae and larvae superparasitized in the fourth stadium were reared to the end of the fifth stadium on six diets,each having the same total amount of casein and sucrose but with different ratios ranging from high protein/no carbohydrate through to low protein/high carbohydrate. Levels of blood protein nitrogen and trehalose, nutrients supporting growth and development of C. congregata, varied with diet and were influenced by parasitism. Different levels of blood metabolites reflected differences in diet consumption, and the relationships between protein nitrogen and trehalose were very similar to those for protein and carbohydrate intake by parasitized and normal larvae on various diets. Dietary nutrient ratio had a significant effect on parasite burden, the numbers of parasites developing in individual host larvae and on parasite biomass. Parasites included individuals that developed and eventually emerged as second instar larvae, moulted to third instars and pupated. Many apparently mature second instar parasites, however, failed to emerge. The proportion of non-emerging individuals varied with diet, and in some cases, parasites failing to emerge were greater in number and total biomass than those that did emerge to complete development. On most diets, the mass of individual parasites was similar regardless of dietary nutrient ratio. Three dimensional models developed to demonstrate the relationships between blood protein nitrogen and trehalose levels and parasite burden and biomass established that the levels of both metabolites are important for supporting growth and development of emerged and non-emerged parasites. In the case of emerged parasites, however, the relationships are linear, and a quadratic function best describes the relationships with non-emerged parasites. Blood metabolite levels supporting the greatest parasite burden and biomass of emerged and non-emerged parasites occupy a region of two dimensional space corresponding to approximately 60-200 mg per insect of protein nitrogen and 60-100 mg per insect of trehalose. Despite the differences in the response of emerged and non-emerged parasites to host nutrition, the present results indicate that host nutrition is not the critical factor determining parasite emergence. The significance of these findings to the biology of C. congregata is discussed.
Analysis of Na+, Cl-, K+, H+and NH4+ concentration gradients adjacent to the surface of anal papillae of the mosquitoAedes aegypti: application of self-referencing ion-selective microelectrodes
Authors: Donini Andrew , O'Donnell Michael J. 
Published: February 2005

SUMMARYIon concentration gradients adjacent to the surface of the anal papillae of larvae of the mosquito Aedes aegypti were measured using self-referencing ion-selective microelectrodes. The gradients were used to calculate estimates of ion fluxes into and out of the papillae. There was a net influx of Na+, Cl- and K+ from the bathing medium and a net efflux of acid and NH4+. No Ca2+ gradients were detectable. Na+ and Cl-influx occurred against a concentration gradient suggesting active transport. Although Na+, Cl- and NH4+gradients were uniform along the length of the papillae, the proximal regions of the papillae in vivo revealed significantly higher H+and K+ gradients compared with distal regions. The calculated ion fluxes at the papillae are sufficient for complete Na+,K+ and Cl- haemolymph replacement in ∼4 h with external ion concentrations of 5 mmol l-1. Ion gradients were also detected adjacent to the surface of isolated papillae; however, Na+and H+ gradients were higher, and Cl- gradients were lower relative to papillae in vivo. The results support previous findings that the anal papillae of mosquito larvae are important structures for ion regulation, and suggest that these structures may be used for the excretion of nitrogenous waste.
The early life history of tissue oxygenation in crustaceans: the strategy of the myodocopid ostracodCylindroleberis mariae
Authors: Corbari Laure , Carbonel Pierre , Massabuau Jean-Charles 
Published: February 2005

SUMMARYWe studied basic principles of respiratory physiology in Cylindroleberididae, Cylindroleberis mariae Baird 1850,which are millimetre-sized crustaceans (myodocop ostracod) having a fossil record dating back to about 425 millions years ago. Facing experimental changes of O2 partial pressures in the range 2-40 kPa (normoxia is 21 kPa), C. mariae lack any regulatory mechanism to adapt their ventilatory and circulatory activity. Thus, the oxygenation status of their internal milieu must follow, as a dependant variable, the ambient oxygenation. Freely behaving C. mariae exhibit a marked diurnal activity rhythm. They are actively swimming in the water column during night, where they inspire in normoxic-normocapnic water. They are resting in self-made nests during daytime, where they are rebreathing in a confined and hypoxic environment. By analogy to extensive previous literature data, we suggest that these changes of respiratory gas content, and the associated tissue gas status, participate to the shaping of their metabolic activity and behaviour. To conclude, as Cylindroleberididae are early crustaceans exhibiting a remarkable stasis since the Palaeozoic, present data illustrates how principles of tissue oxygenation strategy can cover an impressive time scale.
Arginine kinase in the demosponge Suberites domuncula:regulation of its expression and catalytic activity by silicic acid
Authors: Perović-Ottstadt Sanja , Wiens Matthias , Schröder Heinz-C. , Batel Renato , Giovine Marco , Krasko Anatoli , Müller Isabel M. , Müller Werner E. G. 
Published: February 2005

SUMMARY
In Demospongiae (phylum Porifera) the formation of the siliceous skeleton,composed of spicules, is an energetically expensive reaction. The present study demonstrates that primmorphs from the demosponge Suberites domuncula express the gene for arginine kinase after exposure to exogenous silicic acid. The deduced sponge arginine kinase sequence displays the two characteristic domains of the ATP:guanido phosphotransferases; it can be grouped to the `usual' mono-domain 40 kDa guanidino kinases (arginine kinases). Phylogenetic studies indicate that the metazoan guanidino kinases evolved from this ancestral sponge enzyme; among them are also the `unusual'two-domain 80 kDa guanidino kinases. The high expression level of the arginine kinase gene was already measurable 1 day after addition of silicic acid by northern blot, as well as by in situ hybridization analysis. Parallel determinations of enzyme activity confirmed that high levels of arginine kinase are present in primmorphs that had been exposed for 1-5 days to silicic acid. Finally, transmission electron-microscopical studies showed that primmorphs containing high levels of arginine kinase also produce siliceous spicules. These data highlight that silicic acid is an inorganic morphogenetic factor that induces the expression of the arginine kinase, which in turn probably catalyzes the reversible transfer of high-energy phosphoryl groups.
Associative learning of plant odorants activating the same or different receptor neurones in the moth Heliothis virescens
Authors: Skiri H. T. , Stranden M. , Sandoz J. C. , Menzel R. , Mustaparta H. 
Published: February 2005

SUMMARY
The importance of olfactory learning in host plant selection is well demonstrated in insects, including the heliothine moths. In the present study olfactory conditioning of the proboscis extension response was performed to determine the moths' ability to learn and discriminate three plant odorants:β-ocimene and β-myrcene (activating the same receptor neurone type),and racemic linalool (activating two different types). The conditioned stimulus (CS) was an air puff with each odorant blown into a constant air stream and over the antennae, and the unconditioned stimulus (US)was sucrose solution applied first to the antennal taste sensilla, then to the proboscis. Conditioning with increasing odorant concentrations induced increased learning performance. The concentration threshold for learning was 100 times lower for racemic linalool than for the two other odorants,a fact that can be correlated with a higher sensitivity of the moths' antennae to racemic linalool as shown in electroantennogram recordings. After correcting for the different odour sensitivities, the moths' ability to discriminate the odorants was studied. Differential conditioning experiments were carried out, in which moths had to distinguish between a rewarded (CS+)odorant and an explicitly unrewarded odorant (CS-), choosing odour concentrations giving the same learning rate in previous experiments. The best discrimination was found with β-myrcene as the rewarded odorant and racemic linalool as the unrewarded. The opposite combination gave lower discrimination, indicating a higher salience for β-myrcene than for racemic linalool. The moths could also discriminate betweenβ-ocimene and β-myrcene, which was surprising, since they activate the same receptor neurone type. No difference in salience was found between these two odorants.