Bone repair and augmentation using block of sintered bovine-derived anorganic bone graft in cranial bone defect model

To histomorphometrically investigate the repair of critical size defects (CSDs) and bone augmentation in cranial walls using block of sintered bovine-derived anorganic bone (sBDAB) graft. Forty guinea-pigs were divided into test (n=20) and CSD control (n=20) groups. In each animal, a full-thickness bone defect with 9.5 mm diameter was made in the frontal bone. The defects were filled with an sBDAB block soaked in blood in the test group and with blood clot in the CSD control group. The skulls were collected at 0 h (n=2) and 30, 90 and 180 days (n=6/group and period) postoperatively. The volume density and total volume of newly formed bone, sBDAB, blood vessels and connective tissue, vertical thickness of removed bone plug, sBDAB block and graft area were evaluated. The vertical thickness of the adapted sBDAB block was 3.8 times higher than that of the removed bone plug and did not show significant difference between periods, filling in average 29.8% of the total graft region. The sBDAB block exhibited complete osseointegration with the borders of the defect at 90 days. At 90 and 180 days, the vertical thickness of the graft was 279% in the average, and the total volume of bone augmentation was, respectively, 78.8% and 148.5% higher compared with the removed bone plug. The defects of the CDS control group showed limited osteogenesis and filling by connective tissue plus tegument. The sBDAB block can be used to promote repair of CSDs and bone augmentation in the craniomaxillofacial region, due to its good osteoconductive and slow resorptive properties. To cite this article:Cestari TM, Granjeiro JM, de Assis GF, Garlet GP, Taga R. Bone repair and augmentation using block of sintered bovine-derived anorganic bone graft in cranial bone defect model.Clin. Oral Impl. Res. 20, 2009; 340-350.doi: 10.1111/j.1600-0501.2008.01659.x.

Chronic maxillary sinusitis associated with dental impression material

A 62-year-old man was referred for routine treatment of hyperplasia of the mucosa in the anterior lower jaw. An oroantral fistula was detected in the right superior alveolar ridge. The patient had no complaints. Plain radiographs showed a radiopaque foreign body in the posterior region associated with opacification of the maxillary sinus. Computed tomography showed the same hyperdense foreign body located in the posterior lower part of the sinus and an abnormal soft tissue mass in the entire right maxillary sinus. When asked about sinusitis, the patient mentioned occasional episodes of pus taste and intermittent crises of headache lasting for one week. The patient has been edentulous for 20 years. Sinus debridement was performed and the oroantral fistula was closed. The clinical suspicion of the presence of zinc oxide-eugenol paste was confirmed by microscopical and chemical analysis. After 6 months of follow-up, the fistula continued to be closed and sinusitis did not recur. This clinical case of maxillary chronic sinusitis illustrates a different odontogenic origin.

Serotonergic neurons in the nucleus raphe obscurus contribute to interaction between central and peripheral ventilatory responses to hypercapnia

Serotonergic (5-HT) neurons in the nucleus raphe obscurus (ROb) are involved in the respiratory control network. However, it is not known whether ROb 5-HT neurons play a role in the functional interdependence between central and peripheral chemoreceptors. Therefore, we investigated the role of ROb 5-HT neurons in the ventilatory responses to CO(2) and their putative involvement in the central-peripheral CO(2) chemoreceptor interaction in unanaesthetised rats. We used a chemical lesion specific for 5-HT neurons (anti-SERT-SAP) of the ROb in animals with the carotid body (CB) intact or removed (CBR). Pulmonary ventilation (V (E)), body temperature and the arterial blood gases were measured before, during and after a hypercapnic challenge (7% CO(2)). The lesion of ROb 5-HT neurons alone (CB intact) or the lesion of 5-HT neurons of ROb+CBR did not affect baseline V (E) during normocapnic condition. Killing ROb 5-HT neurons (CB intact) significantly decreased the ventilatory response to hypercapnia (p < 0.05). The reduction in CO(2) sensitivity was approximately 15%. When ROb 5-HT neurons lesion was combined with CBR (anti-SERT-SAP+CBR), the V (E) response to hypercapnia was further decreased (-31.2%) compared to the control group. The attenuation of CO(2) sensitivity was approximately 30%, and it was more pronounced than the sum of the individual effects of central (ROb lesion; -12.3%) or peripheral (CBR; -5.5%) treatments. Our data indicate that ROb 5-HT neurons play an important role in the CO(2) drive to breathing and may act as an important element in the central-peripheral chemoreception interaction to CO(2) responsiveness.

Efficacy of a bioactive glass-ceramic (Biosilicate (R)) in the maintenance of alveolar ridges and in osseointegration of titanium implants

Objectives The aims of this research were to evaluate the efficacy of a bioactive glass-ceramic (Biosilicate (R)) and a bioactive glass (Biogran (R)) placed in dental sockets in the maintenance of alveolar ridge and in the osseointegration of Ti implants. Material and methods Six dogs had their low premolars extracted and the sockets were implanted with Biosilicate (R), Biogran (R) particles, or left untreated. After the extractions, measurements of width and height on the alveolar ridge were taken. After 12 weeks a new surgery was performed to take the final ridge measurements and to insert bilaterally three Ti implants in biomaterial-implanted and control sites. Eight weeks post-Ti implant placement block biopsies were processed for histological and histomorphometric analysis. The percentages of bone-implant contact (BIC), of mineralized bone area between threads (BABT), and of mineralized bone area within the mirror area (BAMA) were determined. Results The presence of Biosilicate (R) or Biogran (R) particles preserved alveolar ridge height without affecting its width. No significant differences in terms of BIC, BAMA, and BABT values were detected among Biosilicate (R), Biogran (R), and the non-implanted group. Conclusions The results of the present study indicate that filling of sockets with either Biosilicate (R) or Biogran (R) particles preserves alveolar bone ridge height and allows osseointegration of Ti implants. To cite this article:Roriz VM, Rosa AL, Peitl O, Zanotto ED, Panzeri H, de Oliveira PT. Efficacy of a bioactive glass-ceramic (Biosilicate (R)) in the maintenance of alveolar ridges and in osseointegration of titanium implants.Clin. Oral Impl. Res. 21, 2010; 148-155.doi: 10.1111/j.1600-0501.2009.01812.x.

Polymorphisms of the renin-angiotensin system in patients with multifocal renal arterial fibromuscular dysplasia

Fibromuscular dysplasia (FMD) is an important cause of renal artery stenosis, particularly in young females. Polymorphisms of the renin-angiotensin (RA) system have been implicated in the pathogenesis of hypertension and atherosclerotic vascular disease, and may play a role in the development of FMD. Examination of polymorphisms by PCR for angiotensin-converting enzyme (ACE) I/D, angiotensin II type 1 receptor (AT(1)R) A1166C and angiotensinogen (AGT) M235T and T174M was undertaken in 43 patients with typical multifocal renal arterial FMD (MF-FMD) and in 89 controls. The age of NIF-FMD patients at the time of diagnosis of hypertension did not differ (38.6 + 11.1 years vs 35.5 +/- 10.3 years, P = 0.12) from controls and the proportion (95% vs 86%, P = 0.14) of females was similar. Allele frequencies did not differ significantly between groups, except that MF-FMD patients had a significantly higher frequency of the ACE I allele than control subjects (0.62 vs 0.47, P = 0.026). Since the ACE I allele is associated with lower circulating ACE levels and possibly lower tissue levels of angiotensin II (Ang II), and since Ang II modulates vascular smooth muscle cell growth and synthetic activity, the I allele might predispose to defective remodelling of the arterial media, and thus to the development of MF-FMD. This contrasts with atherosclerotic renal artery stenosis, coronary stent restenosis and carotid intimal thickening, which are diseases affecting the arterial intima, and which are associated with increased frequency of the D allele.

Weketrema gen.n., a new genus for Weketrema hawaiiense (Yamaguti, 1970) comb. n. (Digenea : Lecithasteridae) recently found in Australian marine fishes

A new genus, Weketrema, is erected in the family Lecithasteridae for the species hitherto known as Lecithophyllum hawniiense. Weket, ema hawaiiense (Yamaguti, 1970) comb, n. is redescribed from Scolopsis bilineatus (Bloch) (Perciformes: Nemipteridae) from Lizard Island and Heron Island, Queensland, Plectorhinchus gibbosus (Lacepede) (Perciformes: Haemulidae) from Heron Island and Cheilodactylus nigripes Richardson (Perciformes: Cheilodactylidae) and Latridopsis forsteri (Castelnau) (Perciformes: Latridae) from Stanley, northern Tasmania. The new genus is distinguished from related members of the family Lecithasteridae by its complete lack of a sinus-sac. Although placed in the subfamily Lecithasterinae pro tem, its true subfamily position is not entirely clear. Comment is made on its unusual distribution, both in terms of zoogeography and hosts.

Lecithophyllum kitrii n. sp (Digenea : Lecithasteridae) from Australian coral reef fishes of the genus Siganus

Lecithophyllum kitrii n. sp. is described from Siganus punctatus and S. lineatus off Heron Island on the southern Great Barrier Reef, Australia. It differs from most other species in the genus in its elongate pars prostatica and globular sinus-sac, and from all other species in having the seminal vesicle almost always entirely in the hindbody.

Metastatic lesions in the joint associated with acute inflammatory arthritis after dendritic cell immunotherapy for metastatic melanoma

A 47 year old man undergoing immunotherapy for metastatic melanoma with autologous dendritic cells pulsed with autologous tumour peptide and hepatitis a surface antigen developed acute left ankle arthritis. Gout and acute infection were excluded, and an autoimmune aetiology or occult metastasis were considered. The arthritis initially subsided with indomethacin, but the symptoms recurred 2 months later, and magnetic resonance imaging demonstrated metastatic melanoma of the left talus. Immunohistochemical staining of a cerebral metastatic deposit biopsied 1 week after the onset of arthritis demonstrated T-cell and macrophage infiltration of the tumour. In addition, the patient developed melanoma-specific delayed type hypersensitivity and cytotoxic T-cell responses after vaccination. Thus, the monoarthritis represented an 'appropriate' inflammatory response directed against metastatic melanoma. (C) 2001 Lippincott Williams & Wilkins.

Differential perturbation of neuronal and glial glutamate transport systems in retinal ischaemia

Glutamate is the major excitatory neurotransmitter in the retina and is removed from the extracellular space by an energy-dependent process involving neuronal and glial cell transporters. The radial glial Muller cells express the glutamate transporter, GLAST, and preferentially accumulate glutamate. However, during an ischaemic episode, extracellular glutamate concentrations may rise to excitotoxic levels. Is this catastrophic rise in extracellular glutamate due to a failure of GLAST? Using immunocytochemistry, we monitored the transport of the glutamate transporter substrate, D-aspartate, in the retina under normal and ischaemic conditions. Two models of compromised retinal perfusion were compared: (1) Anaesthetised rats had their carotid arteries occluded for 7 days to produce a chronic reduction in retinal blood flow. Retinal function was assessed by electroretinography. D-aspartate was injected into the eye for 45 min, Following euthanasia, the retina was processed for D-aspartate. GLAST and glutamate immunocytochemistry. Although reduced retinal perfusion suppresses the electroretinogram b-wave, neither retinal histology, GLAST expression, nor the ability of Muller cells to uptake D-aspartate is affected. As this insult does not appear to cause excitotoxic neuronal damage, these data suggest that GLAST function and glutamate clearance are maintained during periods of reduced retinal perfusion. (2) Occlusion of the central retinal artery for 60 min abolishes retinal perfusion, inducing histological damage and electroretinogram suppression. Although GLAST expression appears to be normal. its ability to transport D-aspartate into Muller cells is greatly reduced. Interestingly, D-aspartate is transported into neuronal cells, i.e. photoreceptors, bipolar and ganglion cells. This suggests that while GLAST is vitally important for the clearance of excess extracellular glutamate, its capability to sustain inward transport is particularly susceptible to an acute ischaemic attack. Manipulation of GLAST function could alleviate the degeneration and blindness that result from ischaemic retinal disease. (C) 2001 Elsevier Science Ltd, All rights reserved.

The child of uncertain sex: 17 years of experience

Objective: To review the common clinical presentations, investigations and final diagnosis of children presenting with genital ambiguity. Methodology: Retrospective search of the Royal Children's Hospital, Brisbane, Australia, medical records and personal medical database of one of the authors (MJT) between 1982 and 1999. Results: Fifty-one children aged 0.1-;14 (mean 3.9) years were identified. Twenty-two cases had a 46XX karyotype, and commonly presented with an enlarged phallus (77.2%), urogenital sinus (63.6%) and labioscrotal fold(s) (40.9%). Congenital adrenal hyperplasia (CAH) was the most common final diagnosis (72.7%) . Twenty-nine cases of genital ambiguity had a 46XY karyotype and commonly presented with palpable gonad(s) (75.8%), undescended testes (51.7%), penoscrotal hypospadias (51.7%) and a small phallus (41.3%). Androgen insensitivity and gonadal dysgenesis were the commonest final diagnosis both occurring at a frequency of 17.2%. Conclusions: The results emphasize the importance of CAH as the most common diagnosis in 46XX cases presenting with ambiguous genitalia. Those with 46XY had a wider range of diagnoses. Despite thorough investigation, 23.5% had no definite final diagnosis made.

Noninvasive tests of vascular function and structure: Why and how to perform them

Background Early atherosclerosis involves the endothelium of many arteries. Information about peripheral arterial anatomy and function derived from vascular imaging studies such as brachial artery reactivity (BAR) and carotid intima media thickness (IMT) may be pertinent to the coronary circulation. The prevention and early treatment of atherosclerosis is gaining more attention, and these tests might be used as indications or perhaps guides to the effectiveness of therapy, but their application in clinical practice has been limited. This review seeks to define the anatomy and pathophysiology underlying these investigations, their methodology, the significance of their Findings, and the issues that must be resolved before their application. Methods The literature on BAR and IMT is extensively reviewed, especially in relation to clinical use. Results Abnormal flow-mediated dilation is present in atherosclerotic vessels, is associated with cardiovascular risk factors, and may be a marker of preclinical disease. Treatment of known atherosclerotic risk Factors has been shown to improve flow-mediated dilation, and some data suggest that vascular responsiveness is related to outcome. Carotid IMT is associated with cardiovascular risk factors, and increased levels can predict myocardial infarction and stroke. Aggressive risk factor management can decrease IMT. Conclusions BAR and IMT ate functional and structural markers of the atherosclerotic process. The clinical use of BAR has been limited by varying reproducibility and the influence by exogenous factors, but IMT exhibits less variability. A desirable next step in the development of BAR and IMT as useful clinical tools would be to show an association of improvement in response to treatment with improvement in prognosis.

Molecular basis by which garlic suppresses atherosclerosis

The aim of this study was to determine the mechanism by which the aged garlic extract Kyolic has a protective effect against atherosclerosis. Plasma cholesterol of rabbits fed a 1% cholesterol-enriched diet for 6 wk was not reduced by supplementation with 800 muL Kyolic/(kg body . d). In spite of this, Kyolic reduced by 64% (P < 0.05) the surface area of the thoracic aorta covered by fatty streaks and significantly reduced aortic arch cholesterol. Kyolic also significantly inhibited by 50% the development of thickened, lipid-filled lesions in preformed neointimas produced by Fogarty 2F balloon catheter injury of the right carotid artery in cholesterol-fed rabbits. In vitro studies found that Kyolic completely prevented vascular smooth muscle phenotypic change from the contractile. high volume fraction of filament (V(v)myo) state, and inhibited proliferation of smooth muscle cells in the synthetic state with a 50% effective dose (ED50) of 0.2%. Kyolic also slightly inhibited the accumulation of lipid in cultured macrophages but not smooth muscle, and had no effect an the expression of adhesion molecules on the surface of the endothelium or the adherence of leukocytes. It is concluded that Kyolic exerts antiatherogenic effects through inhibition of smooth muscle phenotypic change and proliferation, and by another (unclarified) effect on lipid accumulation in the artery wall.

Smooth muscle cells of injured rat and rabbit arteries in culture: contractile and cytoskeletal proteins

The aim of this study is to determine whether subpopulations of smooth muscle cells (SMC). as distinguished by variations in contractile and cytoskeletal proteins, appear in the neointima at different times after vascular injury, and/or whether subpopulations develop during serial passaging of these cells. Rat aortae and rabbit carotid arteries were injured with a 2F Fogarty balloon catheter and cultures established from the resulting neointima and the media 2, 6, 12, 16 and 24 weeks later. Cultures were examined at passages 1-5 and subpopulations of SMC categorised by intensity of staining for each protein by immunohistochemistry. Two populations of SMC with different staining intensities ('+ +', '+') were observed for each of the following proteins: alpha -SM actin, SM-myosin, desmin and vimentin. Populations without these proteins were also found. Changes in the percentages of cells expressing these proteins were transitory, indicating that the populations were not limited to a particular tissue (neointima or media), time after injury or passage number. One exception was found in rabbit cultures where the number of desmin-expressing cells quickly decreased with both time after injury and time in culture. Subpopulations of SMC were found at all times after injury in the media and neointima of rat and rabbit arteries, and after multiple passage of these cells. There was no pattern of development of one population suggesting that either no subpopulation has a proliferative or migratory advantage over others, or that only one population exists: that is capable of diverse phenotypic changes. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.

Relationship of glycosaminoglycan and matrix changes to vascular smooth cell phenotype modulation in rabbit arteries after acute injury

Purpose: The phenotype of vascular smooth muscle cells (SMCs) is altered in several arterial pathologies, including the neointima formed after acute arterial injury. This study examined the time course of this phenotypic change in relation to changes in the amount and distribution of matrix glycosaminoglycans. Methods: The immunochemical staining of heparan sulphates (HS) and chondroitin sulphates (CS) in the extracellular matrix of the arterial wall was examined at early points after balloon catheter injury of the rabbit carotid artery. SMC phenotype was assessed by means of ultrastructural morphometry of the cytoplasmic volume fraction of myofilaments. The proportions of cell and matrix components in the media were analyzed with similar morphometric techniques. Results: HS and CS were shown in close association with SMCs of the uninjured arterial media as well as being more widespread within the matrix. Within 6 hours after arterial injury, there was loss of the regular pericellular distribution of both HS and CS, which was associated with a significant expansion in the extracellular space. This preceded the change in ultrastructural phenotype of the SMCs. The glycosaminoglycan loss was most exaggerated at 4 days, after which time the HS and CS reappeared around the medial SMCs. SMCs of the recovering media were able to rapidly replace their glycosaminoglycans, whereas SMCs of the developing neointima failed to produce HS as readily as they produced CS. Conclusions: These studies indicate that changes in glycosaminoglycans of the extracellular matrix precede changes in SMC phenotype after acute arterial injury. In the recovering arterial media, SMCs replace their matrix glycosaminoglycans rapidly, whereas the newly established neointima fails to produce similar amounts of heparan sulphates.

Regulation of LIF receptor expression in vascular smooth muscle

Previous studies in our laboratory have shown that the pleiotropic cytokine leukemia inhibitory factor (LIF) inhibits neointimal formation and the development and progression of atherosclerotic and restenotic lesions in a rabbit model of disease. The present study demonstrates an upregulation of both the LIF receptor (LIFR)-α subunit and the signal transducing subunit gp130 following endothelial denudation of the carotid artery by balloon catheter. Continuous infusion of LIF (30 μg/kg/day) resulted in the downregulation of LIFR-a in injured arteries in vivo. Similarly, smooth muscle cells in vitro treated with LIF exhibited a time-dependent reduction in LIFR-a protein expression and the subsequent reduction in transcription of the TIMP-1 gene. However, in the presence of an intact endothelium, LIFR-a was upregulated in response to LIF, and accordingly the downstream induction of iNOS expression was also increased. Thus, LIF exerts more potent antiatherogenic effects in the vasculature when the endothelium is intact.