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81.
Finzi Eric  MD  PhD    Spangler Amy  MPAS  PA-C 《Dermatologic surgery》2005,31(8):916-922
Background. Redundant facial and neck skin is a major feature of aging and historically has been corrected surgically. Recently, monopolar radiofrequency application has been introduced for nonablative tissue tightening of skin by volumetric heating of the deep dermis. It has been able to improve neck and cheek laxity and periorbital rhytides and to elevate eyebrows. However, questions remain as to the ideal parameters needed to optimize the use of radiofrequency.
Objective. To determine the safety and report on the efficacy of a radiofrequency application that involves a multipass vector (mpave) technique to target facial and neck skin laxity.
Methods. Twenty-five patients (skin types I to V) with mild to severe facial and neck laxity received one treatment session with monopolar radiofrequency. Treatment parameters, adverse events, and digital photographs were recorded. All patients were treated with a multipass vector technique consisting of four to five passes targeted over areas of skin that would most improve facial laxity. The multipass vector (mpave) treatment approach is described. Energy levels ranged from 62 to 91 J/cm2 per pulse.
Results. All patients experienced some immediate erythema and edema, which had completely resolved in most patients within 48 hours. No scarring or dyspigmentation was noted on follow-up at 6 and 12 weeks. Photographic analysis of pre- and post-treatment digital images revealed cosmetic improvement in facial and neck laxity in 96% of patients. The majority of patients demonstrated a moderate or better improvement. Stacked pulses in the submental region were shown to reduce fat.
Conclusions. The direct application of monopolar radiofrequency to facial and neck skin using a multipass vector (mpave) treatment approach was safely tolerated in patients of all skin types. Patient satisfaction correlated well with photographic analysis, and the technique was shown to be efficacious for most patients.  相似文献   
82.
83.
PURPOSE: The purpose of this pilot study was to test a new Le Fort I internal distraction device. PATIENTS AND METHODS: A new internal Le Fort I distraction device designed by 1 of the authors was used in 3 patients with cleft lip and palate and severe maxillary hypoplasia who needed maxillary advancements in excess of 12 mm. Presurgical planning used CASSOS (SoftEnable Technology, Ltd, Hong Kong SAR, China) prediction tracing software and a stereolithographic model to calculate the distraction vector. The distractors were pre-bent and installed on the stereolithographic model and activated to advance the maxilla. Surgery was performed in a conventional manner, and distraction was started after a 7-day latency phase at the rate of 1 mm/day and continued until the presurgical plan was achieved. The distractor was removed after a 3-month consolidation phase. Cephalometric radiographs were taken at the completion of each phase. RESULTS: This new Le Fort I internal distraction device successfully distracted the maxillae as planned in all 3 patients. At the end of the distraction phase, the maxillary advancement was measured at 15.8 mm, 15.8 mm, and 13.5 mm, respectively. In each patient, a clockwise rotation of the maxilla was observed with a tendency to a posterior open bite. Postoperative radiographs also showed that the actual distraction vectors differed from the planned vectors. After the consolidation phase, radiographs showed a relapse of 2.6 mm, 0 mm, and 5.0 mm, respectively. There was no further relapse on 3-month follow-up radiographs. Each case showed radiographic evidence of excellent new bone formation at the osteotomy sites. CONCLUSION: The new Le Fort I internal distraction device produced the necessary advancement in all 3 patients. The study also showed that the actual distraction vector differed from the planned vector. This discrepancy was caused by a clockwise rotation of the maxilla during the distraction. Finally, the study showed a variable relapse rate not previously reported in maxillary distraction.  相似文献   
84.
Four poorly differentiated malignant lesions occurred in a 60-year-old Chinese male in the nasal cavity, submandibular gland, a lymph node in the neck, and the mandible. These malignant lesions developed within an 8-year period and each showed distinctive histological features. Among these malignant lesions, the neoplasm in the submandibular gland presented variegated histological and immunohistochemical (IHC) features and posed a diagnostic challenge in interpretation. Based on microscopic and IHC findings, we believe the diagnosis of teratocarcinosarcoma is justified for the submandibular neoplasm and the metastasis in the lymph node. The pathological features and diagnoses of these malignant lesions are discussed.  相似文献   
85.
86.
One biceps muscle of 8 patients with Duchenne muscular dystrophy was injected at 55 sites with a total of 55 million viable, purified, and contamination-free normal myoblasts (myoblast transfer). The other biceps of each patient was injected with a placebo to serve as a control. The procedure was blinded to the patients, parents, and investigators. Myoblasts derived from a biopsy specimen of the fathers were cultured and purified under strict conditions and carefully screened for microbial contamination. All patients received cyclophosphamide for immunosuppression for 6 or 12 months. No serious complications were observed after myoblast transfer, indicating that the procedure is safe. The overall therapeutic efficiency of myoblast transfer was poor as judged by the results in maximal voluntary force generation, dystrophin content of the muscle, magnetic resonance imaging of the muscle, and the lack of donor-derived DNA and dystrophin messenger RNA in the injected muscle. An improved efficiency of the take of myoblasts might be achieved by using younger cells and injecting the myoblasts with a myonecrotic agent (to increase the prevalence of regeneration) and a basal laminal fenestrating agent.  相似文献   
87.
Poly(ADP-ribose) (polymer) is enzymatically synthesized on nuclearproteins in response to DNA strand breaks. NAD+ is the substratefor this reaction, which is catalyzed by Poly(ADP-ribose)polymerase.This post-translational modification occurs in response to DNAstrand breaks and is thought to play an important role in DNArepair. Polymer synthesis resulting from DNA damage has beendescribed in cultured cells, but measurement is more difficultin animal tissues. In this study, modifications were made toan earlier method to measure carcinogen-induced increases inpolymer levels in vivo. RNase I was added to the enzyme mixtureused to digest polymer to ribosyladenosine (RAdo). This preventedthe inhibition of snake venom phosphodiesterase by RNA. TheHPLC analysis was improved, allowing elimination of the secondboronate affinity chromatography step traditionally used topurify  相似文献   
88.
We identified large-scale heteroplasmic mitochondrial DNA (mtDNA) rearrangements in a 50–year-old woman with an adult-onset progressive myopathy. The predominant mtDNA abnormality was a 21.2–kb duplicated molecule. In addition, a small population of the corresponding partially deleted 4.6–kb molecule was detected. Skeletal muscle histology revealed fibers that were negative for cytochrome c oxidase (COX) activity and had reduced mtDNA-encoded COX subunits. By single-fiber polymerase chain reaction analysis, COX-negative fibers contained a low number of wild-type or duplicated mtDNA molecules (ie, nondeleted). In situ hybridization demonstrated that the abnormal fibers contained increased amounts of mtDNA compared with normal fibers and that most of the genomes were deleted. We concluded that deleted mtDNA molecules were primarily responsible for the phenotype in this patient.  相似文献   
89.
Spectrins are a family of cytoskeletal proteins that organize and link membranes to subcellular motors and filaments. Although traditionally divided into erythroid and non-erythroid forms, the discovery of new spectrin isoforms in various tissues indicates that their distribution is not yet fully characterized. To our knowledge, there is no comprehensive analysis of spectrins in lymphoid malignancies. Using tumor microarrays of paraffin blocks, we immunohistochemically studied 10 lymph nodes with reactive lymphoid hyperplasia and 94 lymph nodes involved by B-cell malignant lymphoma. Expression of spectrins alphaI, alphaII, betaI, betaII, and betaIII was scored using a 20% cutoff for positive immunoperoxidase staining. All spectrin isoforms, except erythroid-specific alphaI spectrin, were detected in lymph nodes with reactive lymphoid hyperplasia. In contrast, various spectrins were lost in particular B-cell malignant lymphomas. Based on the absence of staining for one or more spectrin isoforms in at least 50% of cases, we identified three patterns: (1) loss of alphaII and betaII in follicular lymphoma, grades 2/3 and 3/3; nodular lymphocyte predominance Hodgkin's lymphoma; nodular sclerosis Hodgkin's lymphoma; (2) loss of betaI only in Burkitt lymphoma; and (3) loss of alphaII and betaI in mixed cellularity Hodgkin's lymphoma. In contrast, follicular lymphoma, grade 1/3 and diffuse large B-cell lymphoma retained spectrin in 67-100% of cases. The other lymphoma subtypes retained spectrin in greater than 50% of cases. We identified the loss of particular spectrin isoforms in B-cell malignant lymphomas that have a nodular growth pattern and/or are believed to arise from germinal center B-cells, that is follicular lymphoma, grades 2/3 and 3/3; Burkitt lymphoma; nodular sclerosis Hodgkin's lymphoma; mixed cellularity Hodgkin's lymphoma; and nodular lymphocyte predominance Hodgkin's lymphoma. The absence of particular spectrin isoforms may correlate with transformation or aggressive biologic behavior for some lymphoma subtypes.  相似文献   
90.
This paper raises a number of issues in the assessment of quality of provision for pre-school children before comparing the quality of provision offered by community nurseries to that offered by traditional nursery schools. Quality at all locations was assessed using the Harms and Clifford Early Childhood Rating Scale and was found in each case to be at the good to excellent end of the range. Quality varied over time and between locations although all showed improvements by the third and final rating. It is possible to conclude that the community nursery model can provide an environment of comparable quality to that experienced in traditional nursery schools. It was also possible to conclude that quality is vulnerable to internal and external pressures and that monitoring quality can also have the effect of promoting quality when staff are able to respond to feedback from ratings.  相似文献   
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