The effect of dietary protein levels on the expression of genes coding for four selected protein translation initiation factors in muscle tissue of Wujin pig.

The objective of this study was to investigate the regulatory mechanism underlying the increased muscle protein accumulation in pigs while were fed a high protein diet. The eukaryotic initiation factors (eIFs) have been reported to involve in muscle protein synthesis. We investigated the mRNA and protein expression levels of eIF2B1, 4A1, 4B and 4E in Wujin pigs fed either a high protein (HP: 18%) or a low protein (LP: 14%) diet at 30, 60 or 100 kg body weight, based on real-time PCR and western blotting analyses. Our results indicated that the expression levels of eIF2B1 mRNA and protein were increased by HP diet at all body weight. The HP diet showed higher mRNA and protein levels of eIF4B gene at 60 and 100 kg. The protein expression of eIF4E phosphorylation was increased by HP diet only at 30 kg. These data suggested that the HP diet promoted porcine muscle protein accumulation mainly by up-regulating eIF2B1, 4B and 4E rather than 4A1 expression along the growth stages.

Molecular characterization and tissue expression profile of three novel ovine genes: ATP5O, NDUFA12 and UQCRH from muscle full-length cDNA library of black-boned sheep.

Three novel ovine genes were obtained from muscle full-length cDNA library of black-boned sheep. Sequence analysis revealed that nucleotide sequences of these genes were not homologous to any of the known sheep or goat genes, but these genes have high similarity to ATP synthase subunit O (ATP5O), NADH dehydrogenase (ubiquinone) 1 alpha subcomplex, 12 (NDUFA12) and ubiquinol-cytochrome c reductase hinge protein (UQCRH) genes of other mammal animals (accession number: FJ546085, FJ546078 and FJ546083). The alignment analysis showed that the ovine ATP5O, NDUFA12 and UQCRH genes and proteins have closer genetic relationships with the ATP5O, NDUFA12 and UQCRH genes and proteins from cattle. Conserved domain prediction showed that these three genes included OSCP, NDUFA12 superfamily and UCR-hinge superfamily domains respectively. The deduced sequence of ATP5O, NDUFA12 and UQCRH protein had 213, 145 and 91 amino acid residues, with a molecular weight of approximately 23419.66, 17089.50 and 10657.75 Da and a theoretical isoelectric point of 9.90, 9.68 and 4.45. The secondary structure prediction revealed that 60% helix structure in ATP5O, 60% coils in NDUFA12 and no strand in UQCRH. One potential signal peptide structure in ATP5O protein were found. NDUFA12 and UQCRH have the extremely low possibility of signal peptides. Meanwhile, RasMol was used for visualizing the PDB files generated by Swiss-Model in cartoon or three-dimensional format. ATP5O and UQCRH protein were modeled by Swiss-Model. Tissue expression profile indicated that the ovine ATP5O, NDUFA12 and UQCRH genes could be expressed in all detected tissues including muscles, heart, liver, spleen, lung, kidney and adipose tissues, but the expression abundance of these genes were various in the different tissues. Our experiment supplied the primary foundation for further researches on these three ovine genes.

Solubility of dicalcium phosphate dihydrate by solid titration.

Solid-titration results for hydroxyapatite (HAp), octacalcium phosphate, beta-tricalcium phosphate and tetracalcium phosphate have shown that the only stable phase in 100 mmol x l(-1) KCl at 37 degrees C is HAp. In particular, dicalcium phosphate dihydrate (DCPD) did not form at pH <4.2 (where it is otherwise believed to be stable) except as a metastable phase under conditions of slight supersaturation. The behaviour of DCPD itself under the same conditions requires checking. Solid titration was used to determine the apparent solubility of DCPD in a 100-mmol x l(-1) KCl solution at 37.0 +/- 0.1 degrees C over the pH range 3.2-11.6. The constitution of the precipitate was determined by X-ray diffraction, particle morphology was observed by scanning and transmission electron microscopy, and the precipitate Ca/P ratio was calculated by energy-dispersive X-ray analysis. The titration curve for DCPD was substantially lower than the position reported elsewhere. DCPD was the only identified phase at equilibrium at pH 3.60 and 4.50, but HAp was formed after seeding with 1 mg HAp at DCPD equilibrium at pH 4.47, 3.60 and 3.30. It is concluded that the titration curve observed for DCPD corresponds to the solubility isotherm for the phase, but that this represents a metastable equilibrium. HAp is more stable than DCPD, particularly below pH 4.2. The implications for calcium phosphate studies are profound as the reverse is generally believed to be true. Thus, solubility results and the nature of the carious lesion need reconsideration.

Solid titration of octacalcium phosphate.

Octacalcium phosphate (OCP) is of considerable importance as a precursor in the formation of dental enamel and an intermediate phase in the precipitation of hydroxyapatite (HAp) in bone. However, agreement is poor on the solubility product (pK(sp)), possibly due to the formation of the more stable phase HAp. The system was investigated using solid titration, which has shown reliability in work on HAp and related fluoride minerals, with OCP in 100 mM KCl at 37.0 +/- 0.1 degrees C. The constitution of the end point precipitate was determined by X-ray diffraction and selected-electron area diffraction; the particle morphology and elements present were examined by high-resolution field emission scanning, transmission electron microscopy and energy-dispersive X-ray analysis. The titration curve for OCP was found for pH approximately 3.4-7.4. The precipitate was HAp at pH 3.6 and 4.5; no residual OCP or other phase was detected. Dicalcium phosphate dihydrate (DCPD) was then found to form at pH 3.6 on further addition of OCP titrant after equilibrium had been achieved, possibly due to easier nucleation at lower pH. However, markedly crystalline HAp was formed in equilibrium for OCP titration with HAp seeding, verifying HAp as the more stable phase. A solubility isotherm for OCP was not obtained as HAp appears to be less soluble in the pH range studied. This adds weight to the view that HAp may be the most stable phase of all calcium phosphates, with further doubt being cast on DCPD being the most stable phase below pH 4.2. However, metastable DCPD may form in an Ostwald succession, depending on supersaturation and nucleation conditions.

A prospective, randomized controlled trial of transjugular intrahepatic portosystemic shunt versus cyanoacrylate injection in the prevention of gastric variceal rebleeding.

BACKGROUND AND STUDY AIMS: Both endoscopic obturation and transjugular intrahepatic portosystemic shunts (TIPSs) have proven to be effective in preventing rebleeding from gastric varices. This study compared the efficacy and complications of these modalities. PATIENTS AND METHODS: Cirrhotic patients with acute bleeding from gastric varices were considered for inclusion. After initial control, eligible patients were randomly allocated to two groups: TIPS (n = 35) and obturation using cyanoacrylate (n = 37). In the cyanoacrylate group, treatment was repeated regularly until gastric varices were obliterated. Patients of both groups received regular follow-up. The end points were gastric variceal rebleeding or death. RESULTS: Stent shunt insertion was successful in all TIPS patients, and mean portal pressure gradient decreased from 21.4 +/- 7.5 mm Hg to 7.5 +/- 3.5 mm Hg ( P < 0.001). Variceal obliteration was achieved in 19 patients in the cyanoacrylate group (51 %) compared with seven TIPS patients (20 %) ( P < 0.02). After a median follow up of 33 months, upper gastrointestinal bleeding occurred in 15 TIPS patients (43 %) and 22 cyanoacrylate patients (59 %) ( P = 0.12). Rebleeding from gastric varices was encountered in four TIPS patients (11 %) and 14 cyanoacrylate patients (38 %) ( P = 0.014; odds ratio 3.6, 95 %CI 1.2 - 11.1). Blood transfusion requirements were lower in the TIPS group than in the cyanoacrylate group ( P < 0.01). Survival and frequency of complications were similar in both groups. CONCLUSIONS: TIPS proved more effective than glue injection in preventing rebleeding from gastric varices, with similar survival and frequency of complications.

Solubility of hydroxyapatite by solid titration at pH 3-4.

OBJECTIVES: The solubility isotherm (S) of hydroxyapatite (HAp) is of fundamental importance to saliva chemistry, dental caries and related contexts. It has previously been shown that the locus of the S[HAp] is substantially lower than is commonly reported, and of different slope, probably due to HAps incongruent dissolution. The aim of the present study was to determine the S[HAp] over a wider pH range and to identify the precipitate formed at equilibrium in HAp solid titration. METHODS: The solid titration technique of Leung and Darvell (Leung VW-H, Darvell BW. Calcium-phosphate system in saliva-like media. J Chem Soc Faraday Trans 1991;87(11):1759-64.) was used to investigate the solubility behaviour of HAp at 37.0+/-0.1 degrees C in 100 mM aqueous KCl. The pH range studied overlapped that of earlier work from pH 3.6 to 5.2, for a reproducibility check and validation, and extended to pH approximately 2.9. XRD and EDX were used to identify the precipitates. SEM and TEM were used to observe the morphology. RESULTS: The previous S[HAp] reported by Chen et al. (Chen Z-F, Darvell BW, Leung VW-H. Hydroxyapatite solubility in simple inorganic solutions. Arch Oral Biol 2004;49(5):359-67.) was reconfirmed. An abrupt change of slope of S[HAp] was detected at pH approximately 3.9. No other phase than HAp was found at pH 3.2, 3.6 and 4.1. In particular, brushite (dicalcium phosphate dihydrate) was not detected, even below pH 3.9, where instead calcium-deficient HAp was formed. CONCLUSION: The solid titration method was reconfirmed as reproducible and to yield HAp from pH 2.9 to 5.2. The expected brushite did not appear, but rather a stable calcium-deficient HAp was consistently formed. The chemistry of calcium phosphates needs to be reevaluated.

Solubility of calcium fluoride and fluorapatite by solid titration.

OBJECTIVES: The solubility isotherms, S, of two compounds detected after topical fluoride treatment - calcium fluoride (CaF(2)) and fluorapatite (FAp) - are of fundamental interest in saliva chemistry and in the context of reduction of acid dissolution of teeth, whether through the process of caries or from exogenously ingested acids. Solid titration has shown its reliability and reproducibility for complicated systems that are not suitable for study by the traditional excess-solid method. The primary aim of this work was to ascertain S[CaF(2)] and S[FAp]. METHODS: Solid titration was used for CaF(2) (pH 2.3-9.5) and FAp (pH 2.8-5.1) in 100mM KCl solution at 37.0+/-0.1 degrees C, and further to determine the apparent solubility of hydroxyapatite (HAp) in the presence of 1mM fluoride (pH 3.2-4.8). RESULTS: Peculiar results were obtained at first which were attributed to the adsorption or reaction of fluoride with the reaction vessel glass surface interfering with the intended solution equilibria. Wax-lined glass apparatus resolved this problem. The solubility isotherm of CaF(2) was then as theoretically expected at pH<8, but above this point a new solid species (CaFOH) was postulated to account for the data. The position of FAp was as expected relative to HAp, being about 0.63x less soluble. FAp was the only detectable equilibrium solid at pH 3.2, 3.6 and 4.1. The apparent solubility of HAp was depressed somewhat by the presence of 1mM fluoride. CONCLUSION: The solid titration method was again found to be reliable once glass interferences were eliminated. The interaction of fluoride with borosilicate glass may have affected other work in the field; such work may therefore require re-evaluation. The S[FAp] is very similar to that of HAp determined by solid titration. Excess-solid method results are strongly discrepant from the present determination and may not be reliable, primarily due to lack of solution speciation data for that calculation.

Multidetector CT angiography in diagnosing type I and type IVA spinal vascular malformations.

Multidetector CT (MDCT) angiography is an imaging technique that can provide high-resolution and high-contrast images; however, published reports of MDCT angiography in the evaluation of spinal vascular malformations are limited. We present 2 cases in which MDCT angiography led to diagnosis of a type I (spinal dural arteriovenous fistula) in one and type IVA (perimedullary spinal cord simple arteriovenous fistula fed by a single arterial feeder) spinal vascular malformation, both confirmed by conventional angiography. MDCT angiography can localize the feeding vessel and the fistula, thus greatly reducing the amount of time required for conventional angiography.

[Research hotspot in IgG4-related sialadenitis].

IgG4-related disease is a novel clinical entity which can affect single or multiple organs. IgG4-related sialadenitis is referred to the salivary gland involvement of IgG4-related disease, with or without other organ involvement. IgG4-related sialadenitis is characterized by painless swelling or enlargement of salivary glands, high serum IgG4 level, abundant IgG4+ plasma cells infiltration with fibrosis histologically, and good response to glucocorticoids. With review of related articles, highlight and provide an overview of the most recent and focused findings and concepts of this disease, including the most significant pathogenic process based on kinds of immunocytes, cytokines, as well as participation of epithelial-mesenchymal transition, the clinical value of elevated serum IgG4 concentration and pathological role of infiltrated IgG4+ plasma cells, the potential relationship with salivary gland malignant tumor, the applying and usefulness of positron emission tomography-CT, the diagnostic utility of lip biopsy, treatment, prognosis, and also future perspectives.

Clinical significance of ultrasonography, computed tomography, and biochemical tests in the rapid diagnosis of gallstone-related pancreatitis: a prospective study.

Real-time ultrasonography (US), computed tomography (CT), and biochemical tests were prospectively performed to detect gallstones in 88 consecutive patients immediately after the onset of an attack of acute pancreatitis. The sensitivity of biochemical tests was 84.6% when the patients had three or more positives of five parameters [including serum bilirubin, alkaline phosphatase (AP), gamma-glutamyl transpeptidase (GGT), alanine transaminase (ALT), and alanine transaminase-aspartate transaminase (ALT-AST) ratio]. The sensitivity, specificity, and accuracy were 71.8, 98.0, and 86.4% for US, and 52.9%, 100%, and 79.5% for CT. The sensitivity, specificity, and accuracy were improved to 82.1, 100, and 93.2% by the combination of US and CT, and 94.9, 100, and 97.7% by the combination of US and biochemical tests. Adding CT to the combination of US and biochemical tests resulted in only a slight improvement in sensitivity and accuracy. In conclusion, a combination of US and biochemical tests can provide the best noninvasive method in rapidly detecting gallstones as an etiological factor in acute pancreatitis. Computed tomography is not cost-effective. A positive result of biochemical tests despite a negative finding in US calls for an intensive search for gallstones by further investigation with endoscopic retrograde cholangiography or repeated US examinations.

Disseminated miliary cerebral candidiasis.

We present a case of disseminated intracranial infection by Candida albicans in a 5-year-old girl who had fever and a change of consciousness after surgery for complex congenital heart malformation. MR imaging revealed multiple small ring-enhancing hemorrhagic abscesses. One year after antifungal treatment, the abscesses and ventriculomegaly were almost completely resolved. The patient was discharged in a stable but vegetative condition.

Chorea-ballismus with nonketotic hyperglycemia in primary diabetes mellitus.

PURPOSE: To describe the neuroimaging (Ct, MR, and single-photon emission CT [SPECT]) findings in a series of patients with chorea-ballismus associated with nonketotic hyperglycemia in primary diabetes mellitus and to correlate the imaging findings with the clinical presentation. METHODS: The neuroimaging and clinical data from 10 patients with chorea-ballismus associated with nonketotic hyperglycemia in primary diabetes mellitus were evaluated. Family and drug histories, as well as other causes of chorea, were excluded. All 10 patients had CT, 5 also had MR imaging, and 3 had SPECT examinations. Three had follow-up CT and MR imaging studies, and MR findings were correlated with CT findings in 5 cases. Two experienced neuroradiologists, aware of the diagnosis but blinded to the clinical status of the patients, evaluated all images and reached a consensus as to the final interpretation. RESULTS: CT studies in 9 of 10 patients showed a hyperdense putamen and/or caudate nucleus; in 1, the CT findings were normal. T1-weighted MR images in all 5 patients who had MR imaging (including the patient with a normal CT study) showed hyperintense lesions without significant T2 signal alternation at the basal ganglia. In all 3 of the patients who had SPECT studies of the brain, the scans revealed hypoperfusion at corresponding areas. All 3 follow-up studies depicted resolution of the lesions in the abnormal basal ganglia. Increased hypointensity on T2-weighted and gradient-echo T2*-weighted images was also observed in the sequential MR images. In all patients, the initial side of involvement correlated well with the neuroimaging findings. The chorea resolved within 2 days after treatment of the hyperglycemia in 9 patients. CONCLUSION: In patients with chorea-ballismus associated with nonketotic hyperglycemia in primary diabetes mellitus, CT and T1-weighted MR images show unilateral or bilateral lesions of the putamen and/or caudate. SPECT scans show hypoperfusion. These findings may be related to petechial hemorrhage and/or myelin destruction. Early recognition of these imaging characteristics may facilitate diagnosis of primary diabetes mellitus with hyperglycemia and prompt appropriate therapy.

Recurrent inverted papilloma: diagnosis with pharmacokinetic dynamic gadolinium-enhanced MR imaging.

BACKGROUND AND PURPOSE: Dynamic gadolinium-enhanced MR imaging has been used successfully to identify post-treatment recurrence or postoperative changes in rectal and cervical carcinoma. Our purpose was to evaluate the usefulness of dynamic gadolinium-enhanced MR imaging for distinguishing recurrent inverted papilloma (IP) from postoperative changes. METHODS: Fifteen patients with 20 pathologically proved lesions (recurrent IP, 12; fibrosis or granulation tissue, eight) were enrolled in the study. Three observers, blinded to pathologic results, independently evaluated conventional MR images, including T1-weighted (unenhanced and postcontrast), proton-density-weighted, and T2-weighted spin-echo images. Results then were determined by consensus. Dynamic images were obtained using fast spin-echo sequences at 5, 30, 60, 90, 120, 150, 180, and 300 seconds after the injection of gadolinium-diethylene-triamine penta-acetic acid. Time-signal intensity curves of suspected lesions were analyzed by a pharmacokinetic model. The calculated amplitude and tissue distribution time were used to characterize tissue, and their values were displayed as a color-coded overlay. RESULTS: T2-weighted images yielded a sensitivity of 67%, a specificity of 75%, and an accuracy of 70% in the diagnosis of recurrent IP. Contrast-enhanced T1-weighted images yielded a sensitivity of 75%, a specificity of 50%, and an accuracy of 65%. Pharmacokinetic analysis showed that recurrent IP had faster (distribution time, 41 versus 88 seconds) and higher (amplitude, 2.4 versus 1.2 arbitrary units) enhancement than did fibrosis or granulation tissue. A cut-off of 65 seconds for distribution time and 1.6 units for amplitude yielded a sensitivity of 100% and a specificity of 100% for diagnosing recurrent IP. CONCLUSION: Dynamic MR imaging can differentiate accurately recurrent IP from postoperative changes and seems to be a valuable diagnostic tool.

Intramedullary spinal cryptococcoma: a case report.

Intramedullary spinal cryptococcosis is very rare. We describe a case of intramedullary spinal cryptococcoma at the T12 level in a 60-year-old man who presented with a 3-month history of progressive bilateral lower limb weakness and no obvious immunocompromise. Magnetic resonance (MR) imaging revealed a 1.2 cm diameter mass within the spinal cord at T12 with intermediate signal intensity on T1-weighted images, a slight degree of homogeneous low signal intensity on T2-weighted images, and intense enhancement after infusion of gadopentetate dimeglumine. These findings led to a preoperative diagnosis of intramedullary tumor. After 2 months of postoperative antifungal treatment, the patient's clinical condition had markedly improved. Cryptococcoma should be considered when an enhancing lesion of the spinal cord is found on MR imaging, even in apparently immunocompetent patients. A careful lumbar puncture for cerebrospinal fluid analysis to diagnose cryptococcosis of the central nervous system should be made promptly, as early treatment is associated with a good prognosis.

Detection and assessment of circle of Willis aneurysms in acute subarachnoid hemorrhage with three-dimensional computed tomographic angiography: correlation with digital substraction angiography findings.

In this retrospective study, we examined the usefulness of computed tomographic angiography (CTA) for the detection and assessment of circle of Willis aneurysms in patients with acute nontraumatic subarachnoid hemorrhage (SAH), using selective digital substraction angiography (DSA) as the gold standard. Thirty-five patients who presented with acute, nontraumatic SAH, diagnosed on the basis of unenhanced computed tomography or lumbar puncture findings or both, underwent both CTA and DSA. The CTA images were interpreted for the presence, location, size, and shape of the aneurysm, presence of a neck, and relationship of the aneurysm to adjacent arterial branches. The CTA and DSA images were then compared, with the latter images serving as the gold standard. DSA revealed 37 aneurysms in 32 patients and ruled out intracranial aneurysms in the remaining three. The sensitivity and specificity of CTA for aneurysm detection were 97% and 100%, respectively. The size of the smallest aneurysm shown was 4 mm, and the largest aneurysm was 21 mm. The size and lobularity of the aneurysms estimated from CTA images corresponded well with those estimated from DSA images. In addition, CTA provided a three-dimensional representation of the aneurysmal lesion, which was considered useful for surgical planning. Our results confirm the accuracy of CTA in comparison with DSA. Because of its reliability, minimal invasiveness, and rapidity, CTA may become the technique of choice for neuroradiologic work-up of SAH patients. DSA then would be used to diagnose intracranial aneurysms only in selected, questionable cases.

Intracranial cystic cavernous angioma: a case report.

We present a case of cystic cavernous angioma in an 18-year-old woman with the chief complaint of acute onset of seizures. Computed tomography (CT) and magnetic resonance (MR) imaging revealed a tumor with a slightly enhanced solid calcified portion and a large cystic portion. The patient was well without recurrence 6 months after surgery. The importance of MR imaging in the differential diagnoses is emphasized.

Effect of gadobutrol on VX2 magnetic resonance diffusion-weighted imaging.

The aim of this study was to evaluate the effect of contrast agent gadobutrol on the magnetic resonance diffusion-weighted imaging (MR DWI). Gadobutrol has higher relaxivity than Gd-DTPA and it also has higher formulation 1.0 M than Gd-DTPA 0.5 M. VX2 tumor implanted on the left thigh of each New Zealand rabbit was used as the animal model. The MR scanning was performed using a 1.5 T clinical whole-body MR scanner with an 8-channel knee coil. The results showed that there were significant differences in the signal-to-noise ratio (SNR) and apparent diffusion coefficient (ADC) values between tumor and muscle both before and after gadobutrol injection (0.1 mmol/kg). However, there were no significant differences in the SNR and ADC values of tumor or muscle before and after gadobutol administration. There were also no significant difference in the contrast-to-noise ratio (CNR) values of tumor and muscle before and after gadobutrol injection.

Expression of lipogenic genes during porcine intramuscular preadipocyte differentiation.

Intramuscular fat (IMF) content plays an important role in meat quality. Triglyceride (TG) metabolism in intramuscular adipocytes is strongly associated with the intramuscular fat deposition. To better understand the mechanisms leading to IMF deposition we compared the expression levels of genes related to preadipocyte differentiation and lipogenesis in the intramuscular preadipocytes isolated from the longissimus muscle of Wujin and Landrace pigs. The results showed that the intramuscular preadipocytes could differentiate into mature adipocytes in vitro. Triglyceride content in adipocytes isolated from Wujin pigs was higher than Landrace pigs during the middle and later phases of preadipocyte differentiation. The expression levels of genes related to preadipocyte differentiation such as PPARG and CEBPA showed differential expression between Wujin and Landrace porcine adipocytes during the early stage of differentiation. The expression levels of lipogenic genes such as FASN and SREBF1 were significantly higher in Wujin porcine intramuscular preadipocytes than in Landrace intramuscular preadipocytes at the middle and the later stages of differentiation. This suggests that preadipocyte differentiation and lipogenesis exhibited breed-related scheduling.

Susceptibility-weighted imaging in patients with pyogenic brain abscesses at 1.5T: characteristics of the abscess capsule.

BACKGROUND AND PURPOSE: SWI is a high-resolution 3D, fully velocity-compensated gradient-echo sequence that uses both magnitude and phase data. The purpose of this study was to investigate the phase behavior of the capsule of pyogenic brain abscesses with noncontrast SWI. MATERIALS AND METHODS: Fourteen patients with pyogenic brain abscesses were studied at 1.5T. In all of the patients, SWI images were obtained and reviewed in addition to conventional MR images. Phase values within the abscess capsule were measured and compared with those from the abscess cavities and contralateral normal white matter using 1-way repeated measures ANOVA with post hoc Bonferroni analysis. RESULTS: SWI phase images showed mild hypointesity in 6 patients, isointensity in 3 patients, and mixed iso- to mild hypointensity in 5 patients. The means of phase in the cavity, rim of abscesses, and contralateral normal white matter were -7.552 × 10(-3) ± 0.024, -0.105 ± 0.080, and +0.029 ± 0.011 radians, respectively. Post hoc comparisons showed significant differences between any pair of the 3 regions (abscess cavity, rim capsule, and normal white matter) in SWI (all Ps < .005). CONCLUSIONS: SWI phase imaging shows evidence of paramagnetic substances in agreement with the presence of free radicals from phagocytosis. SWI may provide additional information valuable in the characterization of pyogenic brain abscesses.

In Vitro characterization of low modulus linoleic acid coated strontium-substituted hydroxyapatite containing PMMA bone cement.

Poly (methyl methacrylate) (PMMA) bone cement is widely used in vertebral body augmentation procedures such as vertebroplasty and balloon kyphoplasty. Filling high modulus PMMA increases the modulus of filled verterbra, increasing the risk of fracture in the adjacent vertebra. On the other hand, in porous PMMA bone cements, wear particle generation and deterioration of mechanical performance are the major drawbacks. This study adopts a new approach by utilizing linoleic acid coated strontium substituted hydroxyapatite nanoparticle (Sr-5 HA) and linoleic acid as plasticizer reducing bone cement's modulus with minimal impact on its strength. We determined the compressive strength (UCS) and modulus (Ec), hydrophobicity, injectability, in vitro bioactivity and biocompatibility of this bone cement at different filler and linoleic acid loading. At 20 wt % Sr5-HA incorporation, UCS and Ec were reduced from 63 ± 2 MPa, 2142 ± 129 MPa to 58 ± 2 MPa, 1785 ± 64 MPa, respectively. UCS and Ec were further reduced to 49 ± 2 MPa and 774 ± 70 MPa respectively when 15 v/v of linoleic acid was incorporated. After 7 days of incubation, pre-osteoblast cells (MC3T3-E1) attached on 20 wt % Sr5-HA and 20 wt % Sr5-HA with 15 v/v of linoleic acid group were higher (3.73 ± 0.01 x 104, 2.27 ± 0.02 x 104) than their PMMA counterpart (1.83 ± 0.04 x 104). Incorporation of Sr5-HA with linoleic acid in monomer phase is more effective in reducing the bone cement's stiffness than Sr5-HA alone. Combination of low stiffness and high mechanical strength gives the novel bone cement the potential for use in vertebroplasty cement applications.