Acetabular fractures

There are many questions that remain to be answered regarding the evaluation, classification, and treatment of acetabulum fractures. Without a uniform classification and method of evaluation, a review of the literature can be misleading. Acetabular fractures represent an injury to the articular surface of a major weight-bearing joint and should be treated in accordance with the same criteria used for other intra-articular fractures.     

Scar revision

Scar improvement is an age old endeavor. Multiple modalities exist for improving a scar's appearance. This article will review scar types and offer a brief overview of nonsurgical and surgical options for scar revision.     

Poliovirus vaccine options

As a result of the success of immunization, indigenous wild poliomyelitis has disappeared from the United States. Of 142 confirmed cases of paralytic poliomyelitis reported in the United States from 1980 to 1996, 134 were classified as vaccine-associated paralytic poliomyelitis (VAPP). Persons with VAPP have a disabling illness, and this has caught the attention of the lay media. The risk of VAPP is one case per 750,000 doses distributed for the first dose of oral poliovirus vaccine (OPV) and one case per 2.4 million doses of OPV distributed overall. Because of this risk, most parents prefer a vaccine schedule that starts with inactivated poliovirus vaccine (IPV), even though extra injections are required. IPV does not cause VAPP. New studies show that high immunization rates can be achieved in disadvantaged populations with a schedule starting with IPV. The American Academy of Family Physicians now recommends that the first two doses of poliovirus vaccine should be IPV; that is, either an all-IPV schedule or a sequential schedule of two doses of IPV followed by two doses of OPV. OPV is no longer recommended for the first two doses and is acceptable only under special circumstances, such as when parents do not accept the recommended number of injections.     

Acetabular fractures: easier classification with a systematic approach

Formins are involved in diverse aspects of morphogenesis, and share two regions of homology: FH1 and FH2. We describe a new formin homology region, FH3. FH3 is an amino-terminal domain that differs from the Rho binding site identified in Bni1p and p140mDia. The Schizosaccharomyces pombe formin Fus1 is required for conjugation, and is localized to the projection tip in cells of mating pairs. We replaced genomic fus1+ with green fluorescent protein (GFP)- tagged versions that lacked either the FH1, FH2, or FH3 domain. Deletion of any FH domain essentially abolished mating. FH3, but neither FH1 nor FH2, was required for Fus1 localization. An FH3 domain-GFP fusion protein localized to the projection tips of mating pairs. Thus, the FH3 domain alone can direct protein localization. The FH3 domains of both Fus1 and the S. pombe cytokinesis formin Cdc12 were able to localize GFP to the spindle pole body in half of the late G2 cells in a vegetatively growing population. Expression of both FH3-GFP fusions also affected cytokinesis. Overexpression of the spindle pole body component Sad1 altered the distribution of both Sad1 and the FH3-GFP domain. Together these data suggest that proteins at multiple sites can interact with FH3 domains.     

Treatment options for osteoporosis

The number of women affected by postmenopausal osteoporosis is likely to continue to increase substantially as the population ages. Furthermore, the therapeutic options for such patients are likely to increase. In this brief review, we outline the use of the currently available medications for the management of osteoporosis--namely, estrogen, calcitonin, calcium, and vitamin D. In addition, we discuss the next generation of drugs that are likely to become available in the future--the bisphosphonates and estrogen analogues. As these options become available, the prevention and treatment of osteoporosis will become similar to the management of other common disorders such as hypertension or hyperlipidemia, in which the most appropriate medication may differ for individual patients. Thus, the treatment of osteoporosis is likely to evolve from a decision of whether to initiate estrogen replacement therapy to a more complex decision of the best agent to use for an individual patient.     

基于延迟期权和扩张期权的矿业投资决策研究

矿业项目投资回收期长,不确定因素多,传统评价方法在评价策略性选择权时完全不考虑投资过程中实际存在的不确定性,造成短视决策。文中首先介绍了实物期权的概念、主要类型及定价方法;其次建立了基于延迟期权和扩张期权的矿业投资决策模型;最后以江西省某钼矿投资项目为例进行应用。结果表明:所建立的模型比较全面地反映了矿业投资项目的总体价值,为矿业投资决策提供了一种较好的思路与方法。     

Providing patient-friendly financial options

Having flexible payment options ensures that patients will have all of the motivation and information that they need to accept care in your office. An HCCC simply offers you the chance to make more expensive treatment available to those who need or want it. The small cost of using a HCCC program more than pays for itself--in fact, it costs less than one-third of what you would spend if you were to bill these patients instead. Having consistent financial policies and flexible payment options can dramatically increase your office's productivity and profitability, while expressing your commitment to customer service and high-quality dentistry.     

Osteosynthesis revision in war fractures

A comparison of primary suturing and a new laser weld technique is described for the microsurgical repair of the inferior alveolar nerve in Wistar rats. A reliable method of exposure of the inferior alveolar nerve has been developed in order to allow intraosseous repairs of the nerve involving suturing with 10:0 nylon and a laser weld technique using an albumin-based solder, containing indocynine cardiogreen, plus an infrared (810 nm wavelength) diode laser. Seven cases of microsuture and laser weld repairs were performed with a 29.4% reduction in total operating time in the laser weld group. Histochemical analysis showed comparable mean neuron counts and mean tracer uptake by neurons for the microsuture and laser weld groups. Giant cell reactions were identified in two of the primary suture cases and axon deflection in three cases demonstrating possible advantages of the laser weld technique which showed no adverse reactions by axons or epineurium to the coagulative repair with the solder. The technique of laser weld repair, on initial analysis, therefore appears comparable with traditional suture repairs and indeed may possess several advantages. Further studies are recommended.     

Simultaneous ipsilateral revision total hip arthroplasty and revision total knee arthroplasty with entire femoral allograft

A novel cosalane analog having an extended polyanionic pharmacophore was synthesized in order to target specific cationic residues on the surface of CD4. The design rationale is based on a hypothetical binding model of cosalane to the surface of the protein. The new analog displayed an EC50 of 0.55 microM as an inhibitor of the cytopathic effect of HIV-1RF in CEM-SS cells, which represents a significant increase in potency over cosalane itself (EC50 5.1 microM). Both cosalane and the new analog are inhibitors of viral entry into target cells.     

Acetabular fractures in the elderly: an easily missed diagnosis

Two case reports of low-energy acetabular fractures in elderly people are presented. Both fractures were initially missed because standard hip radiographs were interpreted to be normal. Furthermore, the clinical findings were not strong enough to give the impression of a hip joint fracture. If there is pain in the hip region after a fall, in combination with the absence of clinical findings, appropriate radiographs should be taken to look for acetabular trauma.     

Acetabular osteolysis in total hip arthroplasty: prevention and treatment

Osteolysis can occur around loose, as well as well fixed, cemented or cementless acetabular components in total hip arthroplasty. Histologic studies of tissues biopsied from osteolytic regions suggest an adverse foreign body response to polyethylene and other particulate debris from prosthetic materials. Phagocytosis of these particles by macrophages and giant cells stimulate the production of proteolytic enzymes and inflammatory mediators, all leading to tissue destruction. The importance of polyethylene wear debris is now fully appreciated, and it is clear that this is the major contributor to particulate debris. The authors strongly recommend the avoidance of 32 mm femoral heads, thin acetabular component liners, titanium heads, and acetabular screws when absolutely necessary. We strongly advise 26 mm to 28 mm femoral heads, polyethylene thickness of at least 8 mm, precise liner shell contact, rigid fixation of the acetabular metal shell, intimate bone-acetabular shell contact, and circumferential porous coating of femoral components to decrease the amount of and migration potential of polyethylene debris (Table). Based on our current knowledge, these measures will minimize the problem of acetabular osteolysis.     

Cholelithiasis: current treatment options

Up to 20 percent of the U.S. population may have cholelithiasis, but most of these persons remain asymptomatic. If symptoms or complications develop, several potential management strategies may be used. Open and laparoscopic cholecystectomy are definitive surgical treatments. Nondefinitive methods, such as lithotripsy, indirect dissolution, direct dissolution, sphincterotomy and drainage, have lower success rates but may be indicated in specific cases. Although laparoscopic cholecystectomy is a relatively new technique, its morbidity and mortality rates are comparable to those of open cholecystectomy, and it tends to be less expensive than other surgical methods. For these reasons, laparoscopic cholecystectomy is rapidly becoming the surgical method of choice in the treatment of cholelithiasis.     

Pseudohypoaldosteronism: options for consideration

Pseudohypoaldosteronism (PHA), or mineralocorticoid resistance, displays several features which distinguish it from other steroid resistance syndromes: while at presentation the clinical manifestations may be severe, patients almost invariably survive into adulthood without ill effects in the absence of ongoing treatment; patterns of inheritance are very variable; and, in addition to the more common primary form, it may develop secondary to a variety of conditions. Although the clinical presentation and the finding of absent or greatly diminished binding of aldosterone by peripheral blood leukocytes strongly suggest an underlying abnormality involving the mineralocorticoid receptor (MR), no abnormality in the MR has been identified, unlike other forms of resistance to hormones in the steroid superfamily, in which the underlying abnormality has been traced to a defect in the gene encoding the receptor protein. Molecular studies of the index case have excluded a major cytogenetic abnormality and major deletions or rearrangements of the MR gene. They have also shown that the cDNA sequence corresponding to the open reading frame of the mineralocorticoid receptor molecule is normal, compared with the published human MR cDNA sequence, and that MR mRNA is expressed in apparently normal quantities in peripheral blood mononuclear leukocytes. These findings raise a number of questions about the underlying mechanism for PHA and the mechanisms by which homeostasis is achieved in the absence of effective aldosterone action. With respect to the mechanism(s) of PHA, several possibilities can be envisaged. It is possible, albeit unlikely, that by unfortunate chance small mutations have been missed as a result of cloning only normal alleles in heterozygous patients.(ABSTRACT TRUNCATED AT 250 WORDS)     

Network options for wide-area telesurgery

Telesurgery requires a network with the following characteristics: reliability; acceptable end-to-end delay; the ability to transfer data from sources with widely different data rates; low data error rates. A wide range of network options is currently available and even more will be available shortly. It is concluded that for telesurgery ISDN is the best option at present. In the near future, as they become available commercially. ATM networks are likely to be preferable.