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961.

Background

Spontaneous intracranial hypotension (SIH) is a neurologic condition with the prototypical symptom of orthostatic headache. We report a dramatic case of SIH with life-threatening bilateral hygroma and uncal herniation.

Methods

Case report.

Results

A 44-year-old male patient presenting with orthostatic headache and double vision was diagnosed with SIH. Diagnostic imaging showed meningeal enhancement and bilateral hygroma. A conservative treatment regime was initiated. The patient’s condition rapidly deteriorated with progressive loss of consciousness. Cranial MRI showed beginning uncal herniation. As an emergency treatment measure, an intracranial pressure (ICP) probe was inserted and intrathecal lumbal saline infusion was initiated. This led to a stabilization of ICP and allowed further diagnostics and treatment.

Conclusion

Intrathecal lumbal saline infusion in combination with ICP monitoring can be a life-saving treatment option in unstable SIH patients.  相似文献   
962.
963.
In the last few years, there have been important new insights into the structural biology of G-protein coupled receptors. It is now known that allosteric binding sites are involved in the affinity and selectivity of ligands for G-protein coupled receptors, and that signaling by these receptors involves both G-protein dependent and independent pathways. The present review outlines the physiological and pharmacological implications of this perspective for the design of new drugs to treat disorders of the central nervous system. Specifically, new possibilities are explored in relation to allosteric and orthosteric binding sites on dopamine receptors for the treatment of Parkinson’s disease, and on muscarinic receptors for Alzheimer’s disease. Future research can seek to identify ligands that can bind to more than one site on the same receptor, or simultaneously bind to two receptors and form a dimer. For example, the design of bivalent drugs that can reach homo/hetero-dimers of D2 dopamine receptor holds promise as a relevant therapeutic strategy for Parkinson’s disease. Regarding the treatment of Alzheimer’s disease, the design of dualsteric ligands for mono-oligomeric muscarinic receptors could increase therapeutic effectiveness by generating potent compounds that could activate more than one signaling pathway.  相似文献   
964.
Pore size and porosity control the rate and depth of cellular migration in electrospun vascular fabrics and thus have a strong impact on long-term graft success. In this study we investigated the effect of graft porosity on cell migration in vitro and in vivo. Polyurethane (PU) grafts were fabricated by electrospinning as fine-mesh, low-porosity grafts (void fraction (VF) 53%) and coarse-mesh, high-porosity grafts (VF 80%). The fabricated grafts were evaluated in vitro for endothelial cell attachment and proliferation. Prostheses were investigated in a rat model for either 7 days, 1, 3 or 6 months (n = 7 per time point) and analyzed after retrieval by biomechanical analysis and various histological techniques. Cell migration was calculated by computer-assisted morphometry. In vitro, fine-pore mesh favored early cell attachment. In vivo, coarse mesh grafts revealed significantly higher cell populations at all time points in all areas of the conduit wall. Biomechanical tests indicated sufficient compliance, tensile and suture retention strength before and after implantation. Increased porosity improves host cell ingrowth and survival in electrospun conduits. These conduits show successful natural host vessel reconstitution without limitation of biomechanical properties.  相似文献   
965.
966.
Background: Therapeutic decisions in periodontal surgery are based on the accurate diagnosis of the furcation. Clinical probing is the basic diagnostic tool; however, the accuracy of clinical probing to distinguish Class II and Class III furcation defects is unknown. Therefore, this study compares clinical probing diagnoses to those of computed tomography (CT). Methods: Seventy‐five patients with severe periodontal disease were enrolled in this case series study. A total of 582 furcation sites in molars were assigned for the diagnosis of Class II and Class III furcation defects by clinical probing. Diagnosis based on CT served as a reference. Results: The degree of furcation involvement on clinical findings was confirmed in 57% of the sites, whereas 20% were overestimated and 23% were underestimated compared with the radiologic analysis. Only 32% of Class III furcations in the CT scan were detected clinically. The best correlation of CT scan and clinical probing was found at buccal furcation sites in the mandible, with a κ‐coefficient of 0.52, and buccal furcation sites in the maxilla, κ = 0.38. The κ‐coefficient was 0.35 for lingual furcations, 0.29 for mesial furcations, and 0.27 for distal furcations, showing weaker correlations. Conclusions: CT scans offer more detailed information on furcation involvement than clinical probing. Especially before surgical treatment, three‐dimensional radiographic imaging can be a useful tool to assess the degree of furcation involvement and optimize treatment decisions.  相似文献   
967.
968.
969.
PurposeThe objective was to analyze the effects of growth on the long-term result of maxillary distraction osteogenesis (DO) in cleft lip and palate (CLP).Patients and methodsRetrospective study of 24 CLP cases with long-term follow-up operated for maxillary DO using the Polley and Figueroa technique: 10 patients were distracted during growth, while 14 patients were operated after their growth spurt. Preoperative (T0), 6–12 months postoperative (T1), and ≥4 years postoperative (T2) cephalometric radiographs were evaluated. A classical cephalometric analysis was used to assess the treatment stability, and a Procrustes superimposition method was performed to assess local changes in the maxilla and the mandible.ResultsAt T0, the mean age was of 11.9 ± 1.4 years for growing patient, and 17.9 ± 3.5 years for patient treated after their growth spurt (P < 0.001). Between T0 and T1, a greater increase of the SNA was shown in growing patients (P = 0.036), but the relapse was more important between T1 and T2, with a significant decrease of the SNA (P = 0.002) and ANB (P = 0.032) compared to the patients treated after their growth spurt. Although not significant, growing patients showed greater rotations of their palatal plane and mandibular plane.ConclusionsMaxillary DO in CLP does not correct the growth deficit inherent to the pathology. Overcorrection of at least 20% is advised during growth.  相似文献   
970.

Objective

The aim of the present study was to evaluate whether radiation damage on dental hard tissue depends on the mean irradiation dose the spared parotid gland is subjected to or on stimulated whole salivary flow rate.

Material and methods

Between June 2002 and October 2008, 70 patients with neck and cancer curatively irradiated were included in this study. All patients underwent dental treatment referring to the guidelines and recommendations of the German Society of Dental, Oral and Craniomandibular Sciences prior, during, and after radiotherapy (RT). During the follow-up period of 24 months, damages on dental hard tissues were classified according to the RTOG/EORTC guidelines. The mean doses (D mean) during spared parotid gland RT were determined. Stimulated whole saliva secretion flow rates (SFR) were measured before RT and 1, 6, 12, 24 months after RT.

Results

Thirty patients showed no carious lesions (group A), 18 patients developed sporadic carious lesions (group B), and 22 patients developed general carious lesions (group C). Group A patients received a D mean of 21.2?±?11.04 Gy. Group B patients received a D mean of 26.5?±?11.59 Gy and group C patients received a D mean of 33.9?±?9.93 Gy, respectively. The D mean of group A was significantly lower than the D mean of group C (p?<?0.001). Additionally, the mean SFR 6 months after RT of group A was significantly higher than the mean SFR of group C (p?<?0.01).

Conclusions

Irradiation damage on dental hard tissue correlates with increased mean irradiation doses as well as decreased salivary flow rates.

Clinical relevance

Parotid gland sparing resulting in a dose below 20 Gy reduces radiation damage on dental hard tissues, and therefore, the dose may act as a predictor for the damage to be expected.  相似文献   
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