Kinematics and efficiency of steady swimming in adult axolotls (Ambystoma mexicanum).

The kinematics of steady swimming at a wide range of velocities was analysed using high-speed video recordings (500 frames s-1) of eight individuals of Ambystoma mexicanum swimming through a tunnel containing stationary water. Animals in the observed size range (0.135­0.

Chondrosarcoma of the skull base: CT, MR and pathological features.

We report on CT and MR image findings of a skull base chondrosarcoma. Chondroid mineralisation, a histological feature of chondrosarcoma, can be recognised on CT and is, together with the off-midline position of the tumour, the most characteristic finding. Differentiation is usually made by histological and immunocytochemical staining.

Focal liver lesions: fast T2-weighted MR imaging with half-Fourier rapid acquisition with relaxation enhancement.

Purpose: To compare the clinical usefulness of the half-Fourier rapid acquisition with relaxation enhancement (RARE) technique at T2-weighted magnetic resonance (MR) imaging of focal liver lesions with that of multishot RARE MR imaging and contrast material-enhanced helical computed tomography (CT).

Materials And Methods: Half-Fourier RARE and multishot RARE imaging and helical CT were performed in 48 patients with 102 focal liver lesions and in three patients with diffuse metastatic liver disease. Images were compared qualitatively and quantitatively for image quality, lesion conspicuity, and ability to help differentiate solid lesions from hemangiomas.

The effects of isolation on the mechanics of the human heel pad.

In previous studies on the mechanical properties of the human heel pad (Bennett & Ker, 1990; Aerts et al. 1995) the fat pad and part of the calcaneus was removed from amputated test specimens. The present study tested whether this procedure influences the mechanical behaviour of the sample.

The mechanical properties of the human heel pad: a paradox resolved.

In vivo and in vitro mechanical testing of the human heel pad gave apparently different properties for this structure: the in vivo stiffness is about six times lower, whereas the percentage of energy dissipation is about three times higher (up to 95% loss). It was postulated that this divergence must be ascribed to the lower leg being involved in in vivo heel pad testing. This hypothesis is presently evaluated by applying the two experimental procedures formerly used in the in vivo (an instrumented pendulum) and in vitro (an Instron servo-hydraulic testing machine) investigations on the same isolated heel pad samples.

Deficient antipneumococcal polysaccharide responses in HIV-seropositive patients.

In a prospective study, serological responses and opsonic activity towards Streptococcus pneumoniae were measured in 60 HIV-infected patients and 25 controls after the administration of the 23-valent pneumococcal vaccine (PneumovaxR). Serum samples were collected before vaccination and at weeks 1, 2, 4, and 12 after vaccination and were tested for the presence of antibodies against a mixture of capsular polysaccharide antigens (pool) and against type 3 and type 4 antigens (PS3 and PS4), using an ELISA. A serological response was defined as a two-fold or greater increase in serum titer after vaccination.

Abnormalities of the foot and ankle: MR imaging findings.

Although plain film radiography remains the appropriate imaging technique used in the initial evaluation of ankle and foot disorders, MR imaging has rapidly become important because it provides high soft-tissue contrast and multiplanar capability, and because it can detect subtle marrow abnormalities. MR imaging is most useful for evaluating pathologic processes that involve soft-tissue structures and for evaluating patients whose clinical findings remain unexplained despite normal findings with other imaging techniques. This pictorial essay illustrates various applications for MR imaging of the foot and ankle.

The mechanical characteristics of the human heel pad during foot strike in running: an in vivo cineradiographic study.

The compressive properties of the heel pad during the heel strike when running (barefoot and shod, two subjects, 4.5 m s-1) were studied by means of a high-speed two-dimensional cineradiographic registration (150 frames s-1) of an actual running step. Vertical ground reaction forces were measured with a force platform.

Combined percutaneous balloon dilation and extracorporeal shock wave lithotripsy for treatment of biliary stricture and common bile duct stones.

We report a case of cholangitis, liver abscess, and common bile duct stones in a patient with a benign stricture at a choledochojejunal anastomosis, 3 yr after a complicated duodenohemipancreatectomy. Because surgical reintervention seemed inappropriate, a percutaneous transhepatic balloon dilation was performed after temporary internal-external biliary drainage. Extracorporeal shockwave lithotripsy (ESWL) was successfully applied to fragment all common bile duct stones, with subsequent spontaneous evacuation of all stone fragments through the dilated bilioenteric anastomosis.

Ultrasonography and computed tomography of afferent loop obstruction.

The US and CT findings in a case of afferent loop obstruction after total gastrectomy are reported. A U-shaped fluid filled tubular structure crossing the midline between the abdominal aorta and the superior mesenteric artery (SMA) is a characteristic US and CT image of an afferent loop obstruction. CT is helpful to recognize the bowel wall and to demonstrate its relationship with the biliary system.

Deformation characteristics of the heel region of the shod foot during a simulated heel strike: the effect of varying midsole hardness.

Impact tests using a pendulum were performed on the shod heel region of nine subjects. Both soft- and hard-soled shoes were used. The deformations involved were calculated from the registered decelerations during impact.

Avascular necrosis of the carpal scaphoid: Preiser's disease: report of 6 cases and review of the literature.

Six cases of nontraumatic avascular necrosis of the scaphoid are reported. Two cases were due to chronic steroid intake with several other sites of bone necrosis; for the other 4 cases no etiology could be established. Four were treated with a proximal row carpectomy, 3 with a very satisfying result, whereas one had to be converted into a wrist arthrodesis.

Slp is an essential component of an EDTA-resistant activation pathway of mouse complement.

Slp (sex-limited protein) is a mouse serum protein encoded by a major histocompatibility complex class III gene. It is considered to be a product of a duplicated complement component C4 gene, but without functional activity. Originally it has been found expressed only in adult males with the S region of the H-2d or H-2s haplotype.

Pulmonary lymphangiomyomatosis.

We report a case of pulmonary lymphangiomyomatosis in a young female. CT--and especially high resolution CT--is more specific and sensitive than chest radiography in showing the lung abnormalities. Pathognomonic CT findings are the presence of thin walled cystic air spaces spread throughout the lung parenchyma without nodules and without regional predominance and mostly surrounded by normal parenchyma.

Avascular necrosis of the scaphoid: report of three cases treated with a proximal row carpectomy.

Three cases of avascular necrosis of the scaphoid are reported. One patient, who was using corticosteroids on a regular basis, had other areas of bone necrosis. None of the patients had a history of trauma.

C1-inhibitor prevents PEG fractionation-induced, EDTA-resistant activation of mouse complement.

Fractionation of mouse serum by precipitation with a critical amount of polyethylene glycol 6000 (PEG; 11% w/v) results in a classical and alternative pathway-independent activation of the terminal complement route. The activation can take place after the separation of an activating principle together with the terminal route components from a natural regulator. The isolation and identification of the regulatory component preventing this activation in serum, is subject of this paper.

Experimental Gd-DTPA polylysine enhanced MR angiography: sequence optimization.

Most MR angiography (MRA) techniques use macroscopic blood motion to characterize the flowing spins. A different approach is represented by the use of contrast enhancement of blood pooling agents. The intravenous injection of one of these agents, namely Gd-DTPA polylysine, produces a shortening of the blood T1 below the T1 values of fat and soft tissues.

Hyoid morphology and movements relative to abducting forces during feeding in Astatotilapia elegans (Teleostei: Cichlidae).

In fishes, the abducting hyoid bars push the suspensoria outwards. This force transmission is generally assumed to be important during fast suction feeding (strenuous activity). In Astatotilapia elegans the hyoid symphysis can best be modelled as an oblique hinge.

C5 does not play a major role in the immune response of mice to SRBC in vivo.

The role of complement component C5 in the immune response of mice to sheep red blood cells (SRBC) was investigated. Congenic C5-sufficient and C5-deficient B10. D2 mice and genetically C5-deficient DBA/2 mice, as such or supplemented with C5-sufficient serum, were used as experimental animals.

In vivo anti-complementary activities of the cobra venom factors from Naja naja and Naja haje.

The kinetics of complement (C) depletion and recovery of C levels upon injection of BALB/c mice with cobra venom factors (CVF), from N. naja (C3- and C5-depleting) and N. haje (selectively C3-depleting) were studied.

Functional assay of C5-activating and nonactivating cobra venom factor preparations in the mouse system.

This paper deals with a new, functional assay of cobra venom factor (CVF) preparations with or without C5-activating property. Existing methods lack sensitivity and use diluted human complement as target of inactivation. An adapted assay using diluted mouse serum as complement source was hampered by underestimation of C3 depletion by bystander lysis and an overvaluation of C5 consumption resulting from C3 inactivation in the reagent used.

MR angiography with gadopentetate dimeglumine-polylysine: evaluation in rabbits.

Flow in high-resistance peripheral vessels of the extremities is characterized by a short period of positive flow during systole and almost no flow during diastole. Hence, time-of-flight sequences for MR angiography in high-resistance peripheral vessels are successful only when applied in a plane perpendicular to the vessel course. When applied in a plane parallel to the vessel, the method suffers from the rapid saturation of the inflowing spins.

[High-field magnetic resonance imaging of the liver compared to x-ray computed tomography. Preliminary study apropos of 39 cases].

Thirty nine patients with one or more focal hepatic lesions were examined by contrast enhanced computed tomography (CE-CT) and magnetic resonance imaging (MRI). A variety of pulse sequences--spin echo (SE), gradient echo (GE) and inversion recovery (IR)--have been reported in the literature on MRI concerning the detection and characterization of liver tumors. Multiple studies have compared MRI at different field strengths to CT.