Biologic significance of surface microroughing in bone incorporation of porous bioactive glass implants

A novel chemical etching method was recently developed to create a controlled microrough surface on porous bioactive glass implants. Our earlier in vitro studies showed enhanced attachment of osteoblast-like MG63 cells on a microrough bioactive glass surface. The purpose of our current study was to confirm the in vivo significance of surface microroughening for bone bonding of bioactive glass. Porous bioactive glass cones made of sintered microspheres were surgically implanted in the anterior cortex of rabbit femurs. Peripheral quantitative computed tomography (pQCT), biomechanical push-out testing, histomorphometry, and electron microscopy (BEI-SEM) were used to analyze bone ingrowth and osseointegration at 7, 10, 14, 28, 56, and 84 days after implantation. The results showed that microroughening of the bioactive glass surface significantly enhanced the bone-bonding response of the biomaterial. The positive response was seen in one of the three bioactive glass compositions studied. The affinity index of new bone on the glass surface was significantly (p = 0.02) increased with a trend (p = 0.10) toward improved mechanical incorporation. New bone formation was dependent on the glass composition, and it was found to occur not only through the mechanism of bone ingrowth but also based on in situ osteogenesis within implant interstices. Based on these results, the procedure of microroughening could enhance the osteopromotive properties of certain bioactive glass compositions.     

Reliability of computer-assisted periacetabular osteotomy using a minimally invasive approach

Background

Periacetabular osteotomy (PAO) is the treatment of choice for younger patients with developmental hip dysplasia. The procedure aims to normalize the joint configuration, reduce the peak-pressure, and delay the development of osteoarthritis. The procedure is technically demanding and no previous study has validated the use of computer navigation with a minimally invasive transsartorial approach.

Methods

Computer-assisted PAO was performed on ten patients. Patients underwent pre- and postoperative computed tomography (CT) scanning with a standardized protocol. Preoperative preparation consisted of outlining the lunate surface and segmenting the pelvis and femur from CT data. The Biomechanical Guidance System was used intra-operatively to automatically calculate diagnostic angles and peak-pressure measurements. Manual diagnostic angle measurements were performed based on pre- and postoperative CT. Differences in angle measurements were investigated with summary statistics, intraclass correlation coefficient, and Bland–Altman plots. The percentage postoperative change in peak-pressure was calculated.

Results

Intra-operative reported angle measurements show a good agreement with manual angle measurements with intraclass correlation coefficient between 0.94 and 0.98. Computer navigation reported angle measurements were significantly higher for the posterior sector angle (\(1.65^{\circ }\), \(p=0.001\)) and the acetabular anteversion angle (\(1.24^{\circ }\), \(p=0.004\)). No significant difference was found for the center-edge (\(p=0.056\)), acetabular index (\(p=0.212\)), and anterior sector angle (\(p=0.452\)). Peak-pressure after PAO decreased by a mean of 13% and was significantly different (\(p=0.008\)).

Conclusions

We found that computer navigation can reliably be used with a minimally invasive transsartorial approach PAO. Angle measurements generally agree with manual measurements and peak-pressure was shown to decrease postoperatively. With further development, the system will become a valuable tool in the operating room for both experienced and less experienced surgeons performing PAO. Further studies with a larger cohort and follow-up will allow us to investigate the association with peak-pressure and postoperative outcome and pave the way to clinical introduction.

     

Possible role for mast cell-derived cathepsin G in the adverse remodelling of stenotic aortic valves

Aims Aortic stenosis (AS) is characterized by extensive remodellingof the valves, including infiltration of inflammatory cells,extracellular matrix degradation, and fibrosis. The molecularmechanisms behind this adverse remodelling have remained obscure.In this article, we study whether cathepsin G, an angiotensinII (Ang II)-forming elastolytic enzyme, contributes to progressionof AS. Methods and results Stenotic aortic valves (n=86) and controlvalves (n=17) were analysed for cathepsin G, transforming growthfactor-ß1 (TGF-ß1), and collagens I andIII with RT–PCR and immunohistochemistry. Valvular collagen/elastinratio was quantified by histochemistry. In stenotic valves,cathepsin G was present in mast cells and showed increased expression(P<0.001), which correlated positively (P<0.001) withthe expression levels of TGF-ß1 and collagens I andIII. TGF-ß1 was also present in mast cell-rich areasand cathepsin G induced losartan-sensitive TGF-ß1expression in cultured fibroblasts. Collagen/elastin ratio wasincreased in stenotic valves (P<0.001) and correlated positivelywith smoking (P=0.02). Nicotine in cigarette smoke activatedmast cells and induced TGF-ß1 expression in culturedfibroblasts. Fragmented elastin was observed in stenotic valvescontaining activated cathepsin G-secreting mast cells and innormal valves treated with cathepsin G. Conclusion In stenotic aortic valves, mast cell-derived cathepsinG may cause adverse valve remodelling and AS progression.     

Cephalometric pharyngeal changes after Le Fort I osteotomy in different types of clefts

Fifty patients with clefts (30 unilateral cleft lip and palate (UCLP), 9 bilateral cleft lip and palate (BCLP), and 11 cleft palate only (CP), mean age 25 years) treated with Le Fort I osteotomy were compared retrospectively from cephalograms taken shortly before operation, and at six months and one year postoperatively. Patients with bimaxillary surgery or previous velopharyngoplasty, or both, were excluded. Maxillary advancement was moderate in all groups. One year postoperatively there was a significant change (73%–90% of the surgical advancement) in the sagittal depth of the nasopharyngeal airway but not in the depth of the oropharyngeal airway, the length of the soft palate or the position of the hyoid bone. The nasopharyngeal airway was largest in the CP group both preoperatively and postoperatively. Eleven patients (7 CP, 4 UCLP) had a velopharyngoplasty after the osteotomy to improve their speech. There was no difference in the nasopharyngeal airway in the patients treated by velopharyngoplasty compared with those not so treated, but they seemed to have the shortest maxillas and the greatest surgical changes vertically.     

Cephalic index correlates poorly with intracranial volume in non-syndromic scaphocephalic patients

Objectives

This study aims to compare pre- and postoperative cephalic indexes (CI) with corresponding segmented intracranial volumes (SIV) obtained from volumetric CT in scaphocephalic patients.

Methods

Twenty-four patients (17 boys) who had undergone cranial vault remodeling due to scaphocephaly were compared from 3D-CT imaging datasets. The mean age of the patients at preoperative CT imaging was 5.5 months, and that at 1-year postoperative imaging, 21.5 months. The mean interval between preoperative CT imaging and surgery was 3.3 months. Pearson’s correlation was used to test the correlation of both pre- and postoperative CI with SIV. A paired t test was used to compare differences in the pre- and postoperative mean values of CI and SIV.

Results and discussion

CI correlated poorly with intracranial volume both preoperatively (r?=?0.274) and postoperatively (r?=?0.128). The mean preoperative CI was 65.92 (range 57.99–73.97), and the mean postoperative, CI 70.24 (range 60.23–75.57). The mean preoperative intracranial volume was 877.79 cm³ (range 638–1,256), and the 1-year postoperative volume, 1,249.04 cm³ (range 1,039–1,529). The mean values of both CI and SIV increased significantly after surgery. In one patient, the CI in postoperative measurements was smaller, whereas in all patients, the postoperative SIV was larger than the preoperative intracranial volume. The mean percentage increase in CI was 6.6 %, whereas the mean increase in SIV was 43.1 %.

Conclusion

Cephalic index correlates poorly with intracranial volume in non-syndromic scaphocephalic patients. For some patients, surgery and growth resulted in only subtle or no change in CI despite a notable increase in intracranial volume.     

Serum lipids and lipoproteins during therapeutic amenorrhea induced by lynestrenol and depot-medroxyprogesterone acetate.

Serum concentrations of total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), apolipoprotein A1 (Apo A1), and apolipoprotein B (Apo B) were determined in mentally handicapped subjects (n = 87). 33 women were on lynestrenol 5-10 mg for therapeutic amenorrhea (TA). 18 of them were randomly allocated to continue on lynestrenol and 15 were switched to intramuscular administration of medroxyprogesterone (DMPA). The switch to DMPA resulted in significant increases in HDL-C (33%), Apo A1 (12%), as well as in the HDL-C/LDL-C (48%) and Apo A1/Apo B (22%) ratios. The concentrations of HDL-C and Apo A1 were significantly greater in patients receiving DMPA, than in patients continuing with lynestrenol therapy. The amenorrhea incidence, however, did not differ between the two therapy groups. It is concluded that therapy with DMPA may be associated with smaller atherosclerosis risk than with peroral lynestrenol, because of its weaker effect on HDL-C and A1 levels.     

Long-term effect of pharyngeal flap surgery on craniofacial and nasopharyngeal morphology in patients with cleft palate

The craniofacial morphology of 48 consecutive adult males with isolated cleft palate was studied by means of lateral cephalograms at the mean age of 18.8 years. Twelve of the patients had received pharyngeal flap surgery between 4 and 12 years of age (mean age 6 years) to improve speech. No significant differences were noticed in craniofacial cephalometric relations between the patients who had not had velopharyngeal flap surgery (VPF-) and those who had (VPF+), although the latter showed a tendency toward a more vertical growth direction. In the pharynx, the VPF+ group showed larger sagittal depths of nasopharyngeal airway but smaller depths of oropharyngeal airway. The differences were significant at the levels of the upper nasopharynx and lower oropharynx. According to the hospital records, none of the patients demonstrated persistent airway obstruction. Cephalometry may be useful in evaluating the changes in pharyngeal airway dimensions that may be related to velopharyngeal flap surgery.     

A case study of amnion rupture sequence with acalvaria, blindness, and clefting: clinical and psychological profiles

The purpose of this article is to report the case of a 10-year-old girl born with anophthalmia, bilateral oblique facial clefts, and missing scalp and bones over the temporal and parietal areas of the cranial vault bilaterally. Early amnion rupture seems to be the most probable cause of this rare combination of anomalies. Because no similar case has been reported in the literature so far, we describe here the clinical and psychosocial history of this unusual patient, who has been able to live the intellectually and socially normal life of a blind child in spite of the major craniofacial deformities. The already completed and possible future therapeutic strategies are discussed.     

Sequential changes of noradrenaline content of vein grafts in rats: quantitative estimation by high-performance liquid chromatography using electrochemical detection

Supradiaphragmatic inferior vena cava was transplanted end-to-end into the abdominal aorta of 11-week-old rats of the same inbred strain and same litter using microvascular technique. The grafts were removed 3 days, 4, 8, 16, and 35 weeks postoperatively, and their noradrenaline (NA) content was estimated by high-performance liquid chromatography using electrochemical detection. The amount of NA was significantly lower (P less than .001) in all vein grafts as compared to nontransplanted vena cava. The substantial decrease of NA in the vein grafts throughout the observation period indicates a persistent denervation of the transplant.     

Leakage of cardiac troponin I in aortic valve stenosis

OBJECTIVE: Degeneration and death of cardiomyocytes contribute to the genesis of heart failure (HF) in aortic valve stenosis (AS). We studied whether the ongoing myocyte damage in AS can be detected from circulating cardiac troponin I (cTnI) concentrations. DESIGN AND SETTING: A cross-sectional cohort study in a university hospital. SUBJECTS AND METHODS: We examined 131 adult patients undergoing echocardiography and cardiac catheterization for isolated AS. Blood was sampled from the aortic root and, in a subset of 49 patients, also from the coronary sinus for the determination of cTnI using a sensitive immunoanalysis. RESULTS: Seventy-three patients (56%) had detectable aortic cTnI (> or =5 ng L(-1)) with 30 of them (23% of the total group) having cTnI above the reference limit in healthy subjects (>14 ng L(-1)). Patients with detectable cTnI had a higher prevalence of HF than those with undetectable cTnI (42% vs. 19%, P = 0.004). Plasma cTnI rose from the aorta to the coronary sinus by > or =5 ng L(-1) in 13 of 49 patients with AS (27%) versus in none of 12 control patients free of structural heart disease (P = 0.044). AS patients with transcardiac cTnI gradients > or =5 ng L(-1) had lower left ventricular (LV) ejection fractions than AS patients with gradients <5 ng L(-1) (mean +/- SD, 52 +/- 14% vs. 61 +/- 11%; P = 0.011). CONCLUSIONS: Detectable circulating cTnI is not uncommon in AS and shows a moderate association with the presence of HF. Leakage of cTnI into the coronary sinus associates with impairment of LV systolic function. Monitoring cTnI could provide a means to expose incipient clinical deterioration in AS.