Long-term stability of isolated advancement genioplasty, and influence of associated risk factors: A systematic review

The aim of this review was to investigate the skeletal and soft tissue stability of isolated advancement genioplasty after more than 1 year, and to observe the influence of associated risk factors. A literature search was performed on PubMed, Web of Science, Embase, ScienceDirect, and Cochrane. Only studies with at least 10 patients who underwent an isolated advancement genioplasty, and with a follow-up period of at least 1 year, were included. Of the 2224 records initially identified, eight articles met the eligibility criteria. The mean age of the total study population was 23 years and ranged from 19.1 to 26.5 years in the individual studies. The average surgical advancement at pogonion was 8.2 mm and ranged from 6.2 to 11.7 mm in the individual studies. After 1 year, the horizontal hard tissue relapse at the level of pogonion varied from 0.1 to 2.1 mm. In two studies, this was reported as statistically significant. Regarding the soft tissue, the horizontal relapse varied from 0.3 to 2.9 mm, which was also considered statistically significant in two studies. Isolated advancement genioplasty was found to be a predictable and stable orthognathic procedure in the sagittal plane at both soft and hard tissue levels. The amount of relapse was not associated with the fixation method or with the amount of surgical advancement.

Probing Magnetism in 2D Molecular Networks after in Situ Metalation by Transition Metal Atoms

Metalated molecules are the ideal building blocks for the bottom-up fabrication of, e.g., two-dimensional arrays of magnetic particles for spintronics applications. Compared to chemical synthesis, metalation after network formation by an atom beam can yield a higher degree of control and flexibility and allows for mixing of different types of magnetic atoms. We report on successful metalation of tetrapyridyl-porphyrins (TPyP) by Co and Cr atoms, as demonstrated by scanning tunneling microscopy experiments. For the metalation, large periodic networks formed by the TPyP molecules on a Ag(111) substrate are exposed in situ to an atom beam. Voltage-induced dehydrogenation experiments support the conclusion that the porphyrin macrocycle of the TPyP molecule incorporates one transition metal atom. The newly synthesized Co-TPyP and Cr-TPyP complexes exhibit striking differences in their electronic behavior, leading to a magnetic character for Cr-TPyP only as evidenced by Kondo resonance measurements.

Self-doping of ultrathin insulating films by transition metal atoms

Single magnetic Co atoms are deposited on atomically thin NaCl films on Au(111). Two different adsorption sites are revealed by high-resolution scanning tunneling microscopy (STM), i.e., at Na and at Cl locations. Using density functional based simulations of the STM images, we show that the Co atoms substitute with either a Na or Cl atom of the NaCl surface, resulting in cationic and anionic Co dopants with a high thermal stability. The dependence of the magnetic coupling between neighboring Co atoms on their separation is investigated via spatially resolved measurement of the local density of states.

MR enterography in children with Crohn disease: results from the Belgian pediatric Crohn registry (Belcro)

INTRODUCTION

Magnetic Resonance enterography (MRE) is an imaging modality avoiding ionizing radiation and the discomfort associated with enteroclysis. The results of MRE at diagnosis in the patients of the Belgian pediatric Crohn registry (Belcro) are compared to endoscopical and histological results.

METHODS

Results of MRE, endoscopy and histology were obtained from the medical charts and assigned to one of the following segments: jejunum, ileum, ascending colon, transverse colon, descending colon or rectosigmoid. MRE images were reviewed in a blinded way by 4 radiologists with specific interest in pediatric MRE.

RESULTS

From the Belcro registry, twenty-two patients underwent a MRE during their work-up for Crohn disease. The results of endoscopy, histology and MRE were concordant (either all negative or positive) in the ileum in 16/18 patients and in the rectosigmoid, descending colon, transverse colon and ascending colon in resp 9, 8, 8 and 8/22 patients. In the non-concordant cases (MRE colon negative but endoscopy and/or histology positive), MRE could not reflect the subtle endoscopic or histologic lesions such as erosions that were described.In 4 cases where ileocaecal valve intubation was impossible ileal MRE findings were abnormal. MRE detected ileal stenosis, jejunal lesions and fistula in resp 4/22, 3/22 en 2/22 patients. The 100% and 75% interobserver agreement was resp 50-82% and 773-100% according to the different intestinal segments.

CONCLUSIONS

MRE is a promising imaging modality avoiding radiation in Crohn disease. It should probably become the technique of first choice for the evaluation of extensive small bowel disease in children with Crohn disease.

Structural identification of caged vanadium doped silicon clusters

The geometry of cationic silicon clusters doped with vanadium, Si(n)V(+) (n=12-16), is investigated by using infrared multiple photon dissociation of the corresponding rare gas complexes in combination with ab initio calculations. It is shown that the clusters are endohedral cages, and evidence is provided that Si(16)V(+) is a fluxional system with a symmetric Frank-Kasper geometry.

Combining tiotropium and salmeterol in COPD: Effects on airflow obstruction and symptoms

BACKGROUND

Clinical information on 24-h spirometric efficacy of combining tiotropium and salmeterol compared to single-agent therapy is lacking in patients with COPD.

METHODS

A randomized, double-blind, four-way crossover study of 6-week treatment periods comparing combination therapy of tiotropium 18 microg plus qd or bid salmeterol 50 microg versus single-agent therapy. Serial 24-h spirometry (FEV(1), FVC), effects on dyspnea (TDI focal score) and rescue salbutamol use were evaluated in 95 patients.

RESULTS

Tiotropium plus qd salmeterol was superior to tiotropium or salmeterol alone in average FEV(1) (0-24h) by 72 mL and 97 mL (p<0.0001), respectively. Compared to this qd regimen, combination therapy including bid salmeterol provided comparable daytime (0-12h: 12 mL, p=0.38) bronchodilator effects, but significantly more bronchodilation during the night-time (12-24h: 73 mL, p<0.0001). Clinically relevant improvements in TDI focal score were achieved with bronchodilator combinations including salmeterol qd or bid (2.56 and 2.71; p<0.005 versus components). Symptom benefit of combination therapies was also reflected in less need for reliever medication. All treatments were well tolerated.

CONCLUSION

Compared to single-agent therapy, combination therapy of tiotropium plus salmeterol in COPD provided clinically meaningful improvements in airflow obstruction and dyspnea as well as a reduction in reliever medication.

Tuberculous arthritis of the finger: a forgotten disease

We present a case of a 64-year-old man from Belgian origin with a chronic painful swelling of the third finger. A chronic arthritis from atypical germ was suspected at the third metacarpo-phalangeal joint on the plain radiography, ultrasonography and MR examination. A few months later, he developed thoracic back pain. Plain radiographs, a Technetium-99m bone scan and MR examination of the thoracic spine revealed a spondylodiscitis of the dorsal spine. A tuberculous origin was found on the biopsy of the affected dorsal vertebral bodies D9 and D10 as suspected on the first imaging examinations of the finger. Besides the patient was found to be HIV-positive. This case shows that it is important to think of musculoskeletal tuberculosis particularly in high-risk persons because if left untreated, it can be devastating.

Isomorphous substitution in bimetallic oxide clusters

The geometric and electronic structure of bimetallic oxide clusters is studied as a function of their composition with gas phase vibrational spectroscopy. Infrared multiple photon dissociation spectra of titanium-vanadium oxide cluster anions are measured in the 500 to 1200 wave number range and assigned on the basis of harmonic frequencies calculated using density functional theory. Singly substituted (V(2)O(5))(n-1)(VTiO(5))(-) (n=2-4) cluster anions are shown to form polyhedral caged structures similar to those predicted for their isoelectronic counterparts, the neutral (V(2)O(5))(n) clusters. Upon systematic exchange of V by Ti atoms in V(4-n)Ti(n)O(-)(10) (n=1-4), the structure does not change. The stress induced by the isomorphous substitution results in an increased number of unpaired electrons (n-1) for the Ti-rich systems, leading to a quartet ground state for Ti(4)O(-)(10).

Heavy-metal concentrations in female laying great tits (Parus major) and their clutches

Egg laying may be an additional excretory pathway for heavy metals available to laying female birds. In this study, we examined the relationships between tissue concentrations (both internal organs and feathers) of 10 breeding female great tits (Parus major) and the concentrations in their eggs. We also investigated differences in metal concentrations (Ag, Al, As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Zn) among eggs as a result of the laying order of the eggs. Heavy-metal concentrations in internal tissues were highest in bone (Cr, Ni, Pb, Zn), kidney (Cd), liver (Cu), blood (Al, As, Co, Hg), and intestine (Ag, Mn). In the egg contents, relatively high concentrations of the essential elements Cr, Co, Cu, Mn, Ni, and Zn were found. In eggshells, concentrations of Ag, Al, As, Co, Cr, and Ni were high compared with internal tissue concentrations. Metal concentrations in the egg contents and eggshells were poorly correlated with metal concentrations in internal tissues and feathers; significant positive correlations were found only for cadmium and lead. We found few significant differences in metal concentrations among eggs, and none were according to the laying order of the eggs. The egg volume tended to decrease significantly as egg laying progressed. Our results seem to suggest that no special sampling strategies (e.g., sampling the first egg or pooling eggs from one clutch) are required for most metals.

Comparison of tiotropium once daily, formoterol twice daily and both combined once daily in patients with COPD

This study compared the bronchodilator effects of tiotropium, formoterol and both combined in chronic obstructive pulmonary disease (COPD). A total of 71 COPD patients (mean forced expiratory volume in one second (FEV1) 37% predicted) participated in a randomised, double-blind, three-way, crossover study and received tiotropium 18 microg q.d., formoterol 12 microg b.i.d. or both combined q.d. for three 6-week periods. The end-points were 24-h spirometry (FEV1, forced vital capacity (FVC)) at the end of each treatment, rescue salbutamol and safety. Compared with baseline (FEV1 prior to the first dose in the first period), tiotropium produced a significantly greater improvement in average daytime FEV1 (0-12 h) than formoterol (127 versus 86 mL), while average night-time FEV1 (12-24 h) was not different (tiotropium 43 mL, formoterol 38 mL). The most pronounced effects were provided by combination therapy (daytime 234 mL, night-time 86 mL); both differed significantly from single-agent therapies. Changes in FVC mirrored the FEV1 results. Compared with both single agents, daytime salbutamol use was significantly lower during combination therapy (tiotropium plus formoterol 1.81 puffs.day(-1), tiotropium 2.41 puffs x day(-1), formoterol 2.37 puffs x day(-1)). All treatments were well tolerated. In conclusion, in chronic obstructive pulmonary disease patients, tiotropium q.d. achieved a greater improvement in daytime and comparable improvement in night-time lung function compared with formoterol b.i.d. A combination of both drugs q.d. was most effective and provided an additive effect throughout the 24-h dosing interval.

Quenching of the magnetic moment of a transition metal dopant in silver clusters

Single magnetic atoms embedded in a nonmagnetic host exhibit the Kondo effect in the bulk limit, while in very small molecules the magnetic atom is hardly affected by the matrix. In a combined theoretical (density functional theory) and experimental (photofragmentation and mass spectrometry) study we consider the intermediate case of nanometer sized transition-metal-doped silver clusters. In particular, we provide experimental evidence for enhanced stability of the cobalt-doped silver cluster Ag10Co+ and show theoretically that it has a symmetric endohedral geometry with a closed 18-electron singlet electronic shell structure. This implies that the magnetic moment on the cobalt atom is quenched.

The effect of heavy metal exposure on egg size, eggshell thickness and the number of spermatozoa in blue tit Parus caeruleus eggs

In this study we compared the egg size, the eggshell thickness and the number of spermatozoa trapped on the perivitelline layer of the eggs in three blue tit (Parus caeruleus) populations across a heavy metal pollution gradient. No significant differences were observed in egg characteristics among study sites. Eggs from the two most polluted sites however, had significantly less spermatozoa on the perivitelline layer than eggs from the least polluted site. Our results suggest a significant effect of pollution on blue tit sperm concentrations in the infundibulum. Determining the number of spermatozoa on the egg membranes is relatively cheap and straightforward, which renders this technique a new and useful tool in biomonitoring.

Extremely stable metal-encapsulated AlPb10+ and AlPb12+ clusters: mass-spectrometric discovery and density functional theory study

We report the experimental discovery of extremely stable metal-encapsulated superatom clusters of a group IVA element: AlPb+10 and AlPb+12. Ab initio density functional geometry optimizations at the B3LYP/LANL2DZ level result in a perfect icosahedron with an exceptionally large HOMO-LUMO gap of 3.1 eV for AlPb+12, and a related structure with D(4d) symmetry for AlPb+10, with a HOMO-LUMO gap of 2.6 eV. Their high stability is attributed to the reinforcing influence of the most favorable closed-packed structure and optimally filled electron shells.

Percutaneous transluminal angioplasty of proximal vertebral artery stenosis: long-term clinical follow-up of 16 consecutive patients

We report long-term (average 30 months) clinical and radiological follow-up of 16 consecutive patients with uni- or bilateral proximal vertebral artery stenosis who underwent percutaneous transluminal angioplasty (PTA), without stenting, between 1995 and 1998. Assessment was performed by an independent neurologist. All patients but one remained asymptomatic during follow-up; moderate restenosis was observed in four. PTA of the proximal vertebral artery is safe but in the absence of knowledge of the natural history of atherosclerotic vertebral artery stenosis, whether it is beneficial or not remains unproven. The decision as to whether to perform this procedure is individual.

Effects of heavy metal exposure on aggressive behavior in a small territorial songbird

Several studies have shown that elevated levels of certain heavy metals may affect the behavior of birds and mammals. However, most of these studies were carried out under controlled laboratory conditions; results from free-living populations are scarce. In this study we examined the possible effects of exposure to high heavy metal concentrations on the aggressive behavior of resident great tit (Parus major) males by means of simulated territorial intrusion experiments during the egg-laying and incubation period at a highly polluted and a reference site. We also examined the effects of heavy metal exposure on the breeding performance of the tested couples, and we examined the plasma testosterone concentrations of great tit males in both study sites. We found no significant differences in the aggressive behavior between great tits at the polluted and the reference site during the egg-laying period. During the incubation period, responding male great tits at the polluted site performed significantly more aggressive flights around the decoy than did males at the reference site. During this period, there was also a tendency that more responding males were out of sight of the observer for some time during the experiment at the reference site than at the polluted site and this also for a longer period of time. Other behavioral parameters did not differ significantly between the two sites. Although plasma testosterone levels were higher at the polluted site, they did not differ significantly between the two sites. The tested couples at the polluted site interrupted their laying sequence significantly more and hatching success was significantly reduced compared to the tested birds at the reference site. We found no significant difference in clutch size, the length of the laying interruptions, fledging success, and fledgling age between the two sites. Although our results showed only minor alterations in the territorial aggressive behavior of male great tits exposed to heavy metal pollution, these small changes may have an important influence on the breeding and survival of these birds.

Element- and size-dependent electron delocalization in AuNX+ clusters (X = Sc, Ti, V, Cr, Mn, Fe, Co, Ni)

We investigated the stability of gold clusters doped with open 3d-shell atoms (Sc, Ti, V, Cr, Mn, Fe, Co, Ni). Steps, peaks, and odd-even staggering in mass abundance spectra upon photofragmentation provide evidence for enhanced stability for specific cluster sizes. The observed magic numbers are explained in terms of size- and dopant-dependent modifications of the effective mean-field potential within a phenomenological shell-model approach. Element-dependent 3d electron delocalization and odd-even staggering amplitudes are related to the dopant-atom structure.

Inter- and intraclutch variability in heavy metals in feathers of great tit nestlings ( Parus major) along a pollution gradient

Heavy metal (silver, arsenic, cadmium, copper, mercury, lead, and zinc) concentrations were analyzed in feathers of nestling great tits ( Parus major) collected along a pollution gradient. Differences in metal concentrations along the gradient and inter- and intraclutch variability were investigated. In the immediate vicinity of the pollution source, feathers of nestling great tits contained significantly higher concentrations of silver, arsenic, mercury, and lead than at the sites further along the gradient. The concentrations of copper and zinc, two essential metals, were significantly lower at the second most polluted site. There was no significant difference in cadmium concentrations among sites. Most metals, except cadmium, were significantly positively correlated with each other. There was a significant amount of interclutch variability in feather metal concentrations, and they differed significantly among sites. The amount of inter- and intraclutch variability did not differ significantly, although intraclutch variability of most metals was markedly high. Our study indicates that feathers of great tit nestlings could be used as bioindicators of metal pollution, but attention should be paid in designing representative sampling procedures.

Heavy metals and selenium in feathers of great tits (Parus major) along a pollution gradient

We evaluated the use of great tit (Parus major) feathers as biomonitors for heavy-metal pollution and tested whether there were differences in metal levels in feathers as a function of location, age (first year or older), or gender. In 1998 and 1999, we collected the outermost tail feathers of 185 great tits from four sites along a presumed pollution gradient and one reference site in Antwerp (Belgium) and analyzed them for calcium, selenium, and 13 heavy metals (silver, aluminum, arsenic, cadmium, cobalt, chromium, copper, iron, mercury, manganese, nickel, lead, and zinc). Silver, arsenic, cadmium, cobalt, copper, mercury, nickel, lead, selenium, and zinc concentrations were significantly higher closest to the pollution source (UM site) compared with the other four sites. Heavy-metal and selenium levels were on average 2 to 40 times higher at the UM site compared with the reference site. Aluminum, calcium, and iron levels were not significantly different among sites. We found no general age- or gender-related differences in metal levels except for arsenic and iron, where a significant interaction between site and gender was observed. Our results suggest that feathers of great tits might be useful biomonitoring tools because they reflect the environmental contamination by heavy metals well.

[Supra-aortic arteries angioplasty and stenting: an ultrasonographic follow up]

PURPOSE

Ultrasonographic follow up of patients with supra-aortic arteries angioplasty and stenting was performed to determine the normal characteristics and to detect restenosis or thrombosis at the repair site.

MATERIAL AND METHODS

Twenty-eight patients were followed. The delay between the procedure and the ultrasonographic examination was 1 to 5 years. There were 32 procedures: 7 carotid angioplasties with stenting; 32 vertebral angioplasties (2 stentings), 2 brachiocephalic artery angioplasties (1 stenting); 1 subclavian artery angioplasty. The ultrasonographic examination included morphological and bilateral flow analysis. The usual criteria were measured. Special attention has been given to the morphological aspect of the stents.

RESULTS

All of the carotid stents were patent. No restenosis appeared during the follow up. A parietal thickening was observed in one patient without significant reduction of the arterial lumen. There were one vertebral and one brachiocephalic stent thrombosis. The results of the ultrasonographic examinations correlated well with magnetic resonance imaging.

CONCLUSION

The ultrasonographic follow up of supra aortic arteries angioplasty and stenting is feasible. An early examination is recommended after the vascular procedure to control the efficacy of the repair and to detect and quantify the residual lesions. This phase is compulsory for an optimal long term follow up.

Small subcortical infarcts and primary subcortical haemorrhages may have different risk factors

Primary subcortical haemorrhages (SCH) and small subcortical infarcts (SSI) arise from changes in penetrating perforating arteries. The aim of this study was to compare cerebrovascular risk factors between patients with SCH and patients with SSI. Of 396 patients with a first-ever stroke (226 males; 170 females; median-age: 63), 108 had SSI, and 64 SCH, with or without subcortical infarcts co-existing. Patients with SCH were less likely to have current atrial fibrillation or associated non-lacunar infarcts, but they were more likely to have arterial hypertension (except after exclusion of patients with co-existence of SSI and SCH) and alcoholism, and they were significantly younger and had lower leukoaraiosis scores. The independent factors for SCH were alcoholism, arterial hypertension and lack of significant internal carotid artery stenosis. The only independent factor for SSI was leukoaraiosis score. Hypertension was the most important risk factor in both groups, but its prevalence was higher in the SCH group. Whether patients will develop SSI or SCH probably depends on associated risk factors such as alcohol consumption. Further studies should also take into account the characteristics of arterial hypertension.

[Cerebral venous thromboses: study of the course]

The management of patients with presumed cerebral venous thrombosis has been recently modified by magnetic resonance imaging and evidence that heparin decreases mortality and morbidity. No large consecutive series of patients with cerebral venous thrombosis has been reported since then. The aim of our study was to determine the prognosis factors of patients with cerebral venous thrombosis. Demographic, clinical and radiological characteristics were recorded in a homogeneous series of 18 consecutive patients with cerebral venous thrombosis collected over a 31-month period. All patients were treated by heparin at the acute stage. We found no difference in demographic, clinical and radiological characteristics of the patients according to the 1-month and 6-month outcome. We only found a tendency towards a better 1-month outcome in younger patients (p = 0.06) and in patients with an isolated intracranial hypertension (2p = 0.06). A long therapeutic delay might be a factor of poor prognosis which might be hidden by a better spontaneous outcome in patients with isolated intracranial hypertension in whom the diagnostic delay is longer. A multicentric study allowing a multivariate analysis may therefore be useful to identify prognosis factors in patients with cerebral venous thrombosis.

Postpartum cerebral angiopathy possibly due to bromocriptine therapy

BACKGROUND

Eight cases of benign angiopathy of the postpartum period have been reported previously, none of which involved the administration of bromocriptine.

CASE DESCRIPTION

We describe a case of benign cerebral angiopathy in a 20-year-old woman in the postpartum period occurring after bromocriptine therapy prescribed to suppress lactation.

CONCLUSIONS

Other adverse effects due to vasoconstriction have been reported during bromocriptine therapy, such as myocardial infarction and arterial hypertension. This case suggests that a similar mechanism may be possible in cerebral arteries, although the cause of vasoconstriction remains uncertain.

Portal and pulmonary vessel thrombosis associated with systemic lupus erythematosus and anticardiolipin antibodies

We describe a 26-year-old patient with systemic lupus erythematosus and pulmonary and portal hypertension associated with the presence of anticardiolipin antibodies. Postmortem histological examination revealed the presence of recent thromboses of pulmonary and portal vessels. Our findings further support the concept of pulmonary hypertension being part of the antiphospholipid syndrome and suggest that portal hypertension due to intrahepatic portal vein thrombosis might be another manifestation of this syndrome.

Almitrine has no effect on gas exchange after bilateral carotid body resection in severe chronic airflow obstruction

Using a double-blind cross-over design, a single dose of 100 mg almitrine bismesylate and placebo were administered orally to eight patients with chronic airflow obstruction having undergone bilateral carotid body resection (BCBR) up to two years earlier to alleviate their extreme dyspnoea. In an open study, two other patients have been given almitrine before and three weeks after BCBR. In all patients, arterial blood gases, ventilation and breathing patterns, neuromuscular drive and hypoxic responsiveness have been studied before and three hours after drug administration. Almitrine failed to improve gas exchange in the patients with BCBR, nor did it affect ventilation, ventilatory or hypoxic drive. In the patients studied before and after BCBR, almitrine only improved gas exchange significantly before BCBR. It is concluded that in man almitrine acts solely as a peripheral chemoreceptor agonist and that the well-documented improvement in V/Q relationship is mediated through carotid body stimulation.