Immunolocalization of interstitial collagenase (MMP-1) and tissue inhibitor of metalloproteinases-1 (TIMP-1) in radicular cysts

To investigate the mechanisms involved in expansion of radicular cysts, monoclonal antibodies against interstitial collagenase (MMP-1) and tissue inhibitor of metalloproteinases-1 (TIMP-1) were used to localize the sites of MMP-1 and TIMP-1 expression in 30 radicular cysts. Positive MMP-1 staining was detected in the lining epithelium and subepithelial fibroblasts, macrophages, endothelial cells and osteoblasts/osteocytes in all specimens. Positive TIMP-1 staining was identified in osteoblasts/osteocytes and endothelial cells of all specimens, and in the lining epithelium and subepithelial fibrous connective tissue wall of five radicular cysts with an intense inflammatory cell infiltrate. The number and distribution of positive cells for MMP-1 or TIMP-1 varied widely among individual specimens, but strong immunostaining was constantly detected at sites with prominent subepithelial inflammation. Results here support the hypothesis that MMP-1 may play an important role in the expansion of radicular cysts. The absence of TIMP-1 expression in lining epithelium and subepithelial fibroblasts and macrophages in most cases studied indicated that an imbalance between MMP-1 and TIMP-1 production may lead to radicular cyst expansion.     

Analysis of insulin-like growth factors (IGF)-I, and -II, type II IGF receptor and IGF-binding protein-2 mRNA and peptide levels in normal and nephrectomized rat kidney

Immunocytochemistry, in situ hybridization, and radioimmunoassay were employed to examine the cellular distribution of mRNAs and proteins for IGF-I, II, IGF-II/M6P receptor, IGFBP2 as well as the levels of IGF-I and II in normal and unilaterally nephrectomized (Nx) adult rat kidneys. A similar distribution of immunoreactive IGF-I, and -II as well as IGF-II/M6P receptor was found in the principal cells of the cortical collecting duct and in all cells of the inner medullary collecting duct. In addition, immunostainable IGF-I and IGF-II/M6P receptor were noted in some inner medullary loops of Henle, while IGFBP2 was seen in the collecting ducts and loops of Henle of the inner medullar and the renal vasculature of all animals. By comparison, in situ hybridization revealed IGF-I mRNA only in the medullary thick ascending limbs while IGF-II mRNA was localized to the wall of the renal microvasculature in all kidneys. IGFBP2 mRNA was localized to the renal corpuscle and to inner medullary interstitial cells of all kidneys. These data suggest that renal IGF-I and IGFBP2 are synthesized at upstream sites along the nephron and then transported downstream for interaction with IGF receptors. Following nephrectomy, the renal levels of IGF-I peptide and mRNA were elevated at both 5 and 33 days post-nephrectomy, supporting a potential functional role for IGF-I in stimulating the structural and functional recovery in compensatory hypertrophy.     

Gastroschisis: a radiological and clinical review

The paediatric patient we are describing suffered a scald injury covering 83 per cent of the total body surface area (TBSA). This injury was complicated by Klebsiella pneumoniae septicaemia resulting in multiorgan failure (MOF). Acute respiratory distress syndrome (ARDS), gastrointestinal insufficiency, hepathopathy and wound conversion to full thickness posed the main problems. The boy was ventilated with pressure-controlled mechanical ventilation. The concept of permissive hypercapnia (PHC) resulted in a complete resolution of ARDS within 4 weeks. From our experience, further lung injury among infants and children suffering from severe ARDS can be avoided by using controlled mechanical hypoventilation. It is a simple and safe technique that allows adequate oxygenation.     

Efficient cryogenic design,a system approach

With the increasing stress on consumable budgets, the goal of decreasing helium consumption of cryogenic system components has become a major issue. Although much progress has recently been made (improvements in helium Dewar technology and high T_c magnet leads are good examples) the potential to improve efficiency is greater when the entire cryogenic system is viewed as an interacting unit.     

Outcome in elderly injured patients: injury severity versus host factors

To evaluate the differences between the outcome of elderly patients with severe injuries and that of their contemporaries with a less severe injury, we reviewed 42 severely injured elderly patients and compared them with 76 patients with a femoral neck fracture. We analysed the influence of injury severity and host factors (age, sex and pre-injury medical status) on outcome. The in-hospital mortality rate was 31 per cent in the severely injured patients and 3 per cent in those with a femoral neck fracture. Home was the main discharge destination in the severely injured elderly (34 per cent) and a nursing home in patients with a femoral neck fracture (65 per cent). Functional outcome 1 year after injury was better in the severely injured elderly group. Long-term survival was mainly determined by host factors and not by injury severity. Physicians and policy makers should be careful in predicting the outcome of elderly injured patients merely on the basis of injury severity, because host factors are of greater importance.     

Validation of multifrequency bioelectrical impedance analysis in monitoring fluid balance in healthy elderly subjects

BACKGROUND: Multifrequency Bioelectrical Impedance Analysis (MFBIA) is a novel method to assess body composition in elderly subjects. However, it is unclear whether MFBIA can detect changes in body water compartments in elders. We aimed to determine the within-subject variability of MFBIA and the responsiveness to a diuretic intervention in aged subjects with a stable fluid balance. METHODS: We selected 12 healthy active elderly subjects (5 male, 7 female) with a mean age of 75 years. Total body water and extracellular fluid (ECF) were measured by deuterium oxide- and potassium bromide-dilution techniques. Within-subject variability in total body MFBIA was assessed by performing four measurements at 1, 5, 50, and 100 kHz within a 2-month period. Subsequently, responsiveness of MFBIA to the ECF loss caused by oral administration of 40 mg of furosemide was determined. RESULTS: Within-subject variability in MFBIA at 1, 5, 50, and 100 kHz expressed as standard deviations was 21, 19, 14, and 14 Ohm (omega), respectively. Furosemide caused a mean weight loss of 1.8 +/- 0.6 kg, which resulted in significant increases in impedance of 57 +/- 24 omega at 1 kHz and 37 +/- 12 omega at 100 kHz (p < .001). The responsiveness of MFBIA for the diuretic intervention was best at 5 kHz (responsiveness index = 1.98). CONCLUSIONS: Within-subject variability of MFBIA was small in healthy elderly subjects with stable fluid balance. Responsiveness of MFBIA to 9% furosemide-induced ECF loss was excellent. These data support the necessity for further clinical assessment of the value of MFBIA in monitoring fluid balance in geriatric patients.     

Reattachment of coronal fragments: operative considerations for the repair of anterior teeth

The maxillary incisors occupy an extraordinary position in the dental arch. They set the aesthetic tone, and their influence on the overall well-being of the individual cannot be overemphasized. However, their eruptive pattern and dominance carries a significant risk for trauma, particularly in childhood. More than half of all traumatic dental injuries involve the central incisors. In the past, fractured teeth were either extracted, trimmed and leveled, or restored with cast restorations. The learning objective of this article is to stimulate a shift in treatment strategy towards aesthetic reattachment of fractured segments. Indications and limitations for reattachment are outlined, including the primary and secondary restorative efforts. Innovative operative techniques that improve the aesthetic, biologic, and mechanical variables of the reattachment treatment option are presented.