Composite grafts in the treatment of osteosarcoma of the proximal humerus

Treatment of osteosarcoma (OSA) of the proximal humerus poses many difficulties and challenges to the treating team. Between 1993 and 2000, we treated 11 patients (three women, eight men; age range, 17–74 years) suffering from OSA of the proximal humerus by composite: massive allografts and long humeral prosthesis. At presentation, 10 patients were at stage 2-B and one at stage 3-B of OSA. One patient presented with a pathologic fracture. All patients except patient No. 6, received preoperative chemotherapy followed by limb salvage surgery and postoperative chemotherapy.Surgical margins were graded as wide in all patients. Postoperative complications included non-union at the allograft/host junction (which united after auto grafting) and superficial wound infections that resolved after antibiotic therapy. All surgical procedures were performed by a team headed by an orthopedic oncologist and shoulder surgeon. At latest follow-up (December 2001) all patients, with the exception of one (who was at stage 3-B at presentation) were alive, and had good function of the upper limb. It is our opinion that the team approach comprising an orthopedic oncologist and shoulder surgeon greatly contributed to the good surgical outcome, and hence the good survival and functional results of the patients. Bone allograft offers a modular malleable durable solution to the resected bone segment.     

Morphometry and allometry of the primate humerus

The primate distal humerus has been used both in phylogenetic reconstruction and in assessing locomotor and postural adaptations. This study uses an allometric approach to predict locomotor patterns of extant primates regardless of phylogenetic position. By showing the relationship between form and function in living primate taxa it will be possible to use this data set to predict locomotor behavior of extinct primates. Several linear measurements were taken from the distal humerus of 71 extant primate species (anthropoids and prosimians). Allometric regressions of each measurement were performed with mandibular M₂ area as a surrogate for body size. These measurements were used to determine if significant differences in distal humerus morphology exist among locomotor groups. The results were then used to test several hypotheses about the relationship between humeral form and function. For example, the hypothesis that suspensory primates have a large medial epicondyle is confirmed; the hypothesis that terrestrial quadrupeds have a deep olecranon fossa could not be confirmed with quantitative data. In addition to this hypothesis testing, the residuals from the allometric regressions of the humeral measurements were used in a discriminant functions analysis to estimate locomotor behavior from distal humerus morphology. The discriminant functions analysis correctly reclassified 64/71 (90%) species.     

几种染色剂对桔小实蝇产卵孔的染色效果

为寻找水果上桔小实蝇产卵情况的快速检测方法,本文测定了甲基蓝、龙胆紫、品红、曙红、藏红和刚果红等6种染色剂对水果上桔小实蝇Bactrocera dorsalis（Hendel）产卵孔的染色效果。结果表明染色剂对可疑水果进行染色,若有产卵孔,产卵孔可迅速被染色,染色率最高可达100％。筛选出甲基蓝、藏红和刚果红作为芒果、番石榴和夏橙的最适染色剂,各种染色剂在浓度为0．5％时染色效果较佳,同时对持续冷藏保存后的水果上的产卵孔仍然具有较高的染色率。     

Straining of the intact and fractured proximal humerus under physiological-like loading

Surgical treatment of proximal humeral fractures remains challenging in elderly patients, primarily due to insufficient implant fixation. Both bone quality and physiological-like loading conditions are commonly overlooked during pre-clinical in vitro evaluation. However, this knowledge is necessary in order to improve surgical treatment of the proximal humerus and the mechanical behavior of implants, particularly in patients with complex fractures and weak bone stock. We hypothesize that the bone quality has a high influence on the bone straining, independent of the arm position. The goal of this study was to determine the straining of the intact and fractured proximal humerus under physiological-like loading conditions. Furthermore, the impact of augmentation on tissue straining was evaluated.

Two representative humeri were selected for this study, one osteoporotic and one reference quality, and scanned using both QCT and DEXA (average DEXA VALUE=0.26 and 0.49 g/cm² respectively). Subcaptial defects were generated, then stabilized with a plate prior to mechanical stiffness testing. From the QCT data, finite element models were generated and the in vitro stiffness tests analytically simulated. Under physiological-like loading conditions, the straining of the bone and implant were analyzed for 0°, 90° forward flexion, and 90° abduction.

Maximal strain values were found for the intact and fractured bone at 90° abduction. This study demonstrates that the straining in a fractured bone of poor quality leads to considerably higher bone strains (up to +30%) than in a more healthy bone. Augmentation of a central void under physiological-like loading with commercial cement led to mechanical failure at the bone–cement interface.

New concepts for the surgical treatment of complex fractures of the proximal humerus should take bone distribution into account and thereby allow effective treatment of fractures in osteoporotic patients. The ultimate salvage procedure of augmentation has mechanical limitations as long as current cement materials are used in osteoporotic patients.     

Septal fracture in Nautilus: implications for cephalopod paleobathymetry

Analysis of septal geometry, as embodied in the septal strength index model developed by Westermann (1973, Lethaia 6). , has become a prime avenue for estimating living depths of fossil cephalopods. We have examined the fracturing of Nautilus septa, and its bearing on strength index, by inducing septal rupture under the action of hydrostatic pressure. We found that: (1) septa which actually fail under pressure are not generally weakest as defined by their strength indices; (2) septal strength as defined by the strength index is not correlated with rupture pressure; and (3) most instances of septal failure originate in septal sutures, not in the septa. These results indicate that: (1) septal strength index does not yield wholly reliable strength or depth estimates; and (2) the shortcomings of the strength index model stem from its inability to account for complexities of mechanical failure in morphologically complex cephalopod shells.     

Septal aperture of the humerus in a mediaeval human skeletal population

Humeral septal aperture is studied in a large Mediaeval skeletal series from England. The aims are to investigate associations between septal aperture and sex, age, side and humeral robusticity; and to evaluate any associations with relative projection of ulna coronoid and olecranon processes. In this way, it is hoped to shed light on age at occurrence and the causation of the trait. Results showed a paucity of cases in juveniles. In adults, the trait was more common in left bones and in females. No association was found with humeral robusticity or humero-ulnar conformation. Detailed morphological study of humeral septa of individuals with and without apertures suggested that septal aperture forms via resorption from the anterior surface of the septum. In this group, apertures appear generally to form in early adult life. It is suggested that in the study group septal aperture generally arises from impingement on the humeral septum by the coronoid and olecranon processes, chiefly the former. It is tentatively suggested that frequency of septal aperture may be an index of joint hypermobility in earlier populations.     

The role of body mass in thermoregulation

Inbred Fisher and Buffalo rats were raised in small and in large litters and by such litter manipulation, large- and small-bodied animals were obtained within the same strain. When the rats were exposed to extreme cold and heat, it appeared that large-bodied rats in both strains survived longer in cold and small-bodied rats survived longer in heat. The two trends were clearly evident, and individual correlations between survival time and body mass were generally significant. However, there were also irregularities in such correlations. It is concluded that this is due to the fact that body mass is only one factor determining temperature tolerance in addition to hypothalamic, endocrine, and possibly neurochemical factors not known to be correlated to body mass.     

Allograft reconstruction of the distal humerus after resection of a breast solitary metastasis: eleven years follow-up

Resection is a rare indication for the treatment of solitary skeletal metastasis (SSM), and provides an opportunity to cure the oncologic patient. Reconstruction after resection can imply a difficult problem depending on the size and the location of the metastasis. In the reported case, an en-bloc resection of a SSM of a breast cancer located in the distal humerus was performed in 1990. Reconstruction of the osteoarticular defect has been achieved with a massive allograft. At eleven years follow-up the patient remains free of illness and shows a good functional result. With the result obtained in the reported case, we suggest that osteoarticular allograft can be of considerable value for reconstruction after excision of SSM in the distal humerus, and that cure can be achieved with the radical resection of a SSM of breast cancer. This revised version was published online in July 2006 with corrections to the Cover Date.     

Sex determination of prehistoric central California skeletal remains using discriminant analysis of the femur and humerus

A large sample (n = 370) of Central California prehistoric skeletal remains was analyzed for sexual dimorphism of long bones using nine femoral and nine humeral dimensions. Sex of all individuals was assessed using traits of the os pubis. Discriminant analysis was done separately for the robust Early Horizon sample and the Middle/Late Horizon sample. Use of multiple variables did not produce appreciably better results over the use of several of the best variables, analyzed singly. Attention is focused on measurements of maximum diameter femoral head, femoral bicondylar width, and diameter of the humeral head (transverse or vertical). These variables produce excellent separation of the sexes with about 90% accuracy for the Middle/Late Horizon sample. They have been overlooked in the recent literature in which the relative values of length versus midshaft dimensions are debated. The measurements found to be superior in this study are taken at the ends of the bones where durability of these regions is indicated by large sample sizes found in this study. We suggest workers redirect their focus from the midshaft to the ends of the long bones. The discriminant analyses presented here have greater accuracy than most claims for either long bone or cranial sex determination. These standards, based on two samples with differing robusticity, may have applicability for workers in other areas who lack large skeletal samples.     

Septal Accessory Pathway: Anatomy,Causes for Difficulty,and an Approach to Ablation

Accessory pathway (AP) ablation is one of the most satisfying invasive electrophysiology procedures associated with high success rates and relatively few complications. Nevertheless, when APs are found on the cardiac septum, ablative procedures become complex, and unique pitfalls need to be avoided.These difficulties with septal ablation are magnified in the pediatric population. The relatively small heart, rapid nodal conduction, and proximity of the arterial system specifically complicate septal ablation in children. The electrophysiologist must use every tool in his or her armamentarium, including exact delineation of pathway location, identification of pathway potentials, detection of the presence of pathway slant, etc. In addition, an exact knowledge of the complex anatomy of the cardiac septum, including the posteroseptal space, the aortic cusp region, and the proximity of the AV conduction system and coronary vessels, becomes mandatory.In this review, we describe the developmental anatomy and regional anatomy of septal accessory pathways. We then discuss approaches to map specific to pathways in particularly problematic regions at or near the septum, including venous and aortic cusp related accessory pathways.     

Determination of crown-rump length from fetal long bones: humerus and femur

Lengths of the ossified diaphysis of the humerus and femur were measured in 50 fetuses ranging from 65 to 290 mm Crown-Rump length. A significant correlation was found between the diaphyseal length and the CR length. No appreciable difference was noted in diaphyseal lengths of the humerus and femur in fetuses of 85 mm CR length or below. Various growth phases were observed. The difference in length of the femur and humerus is due to a comparative slow growth of the humerus during the later period of prenatal life. Diaphyseal growth rates of the humerus and femur are 0.18 mm and 0.21 mm respectively for every 1 mm increase in CR length. Regression coefficients for the lengths of the ossified shaft of the humerus and femur are 5.35 and 5.00 respectively. With the help of these coefficients, CR length of the fetus was estimated within a range of ± 15 mm. From the estimated CR length, age of the fetus was determined with the help of a standard age and size curve with reasonable accuracy.     

Neurite-Promoting Activities of Phosphatidylinositol and Other Lipids on Fetal Rat Septal Neurons in Culture

Neurite-promoting activities of lipids were assessed using serum-free cultures of fetal rat septal neurons. The most potent one was phosphatidylinositol (PI), followed by PI 4-phosphate, phosphatidylserine, sphingomyelin, and phosphatidylcholine. The EC50 value for PI was 1.5 micrograms/ml (1.8 microM), and activity was maximal at 4 micrograms/ml (56% of total cells had neurites after 24 h). Cerebroside, sulfatide, and di- and triacylglycerols showed relatively low activities. Synthetic dipalmitoyl phosphatidylcholine was also active, with a maximal activity (47%) at 100 micrograms/ml, a finding implying that the unsaturated fatty acid moiety is not released and further used as substrate for the arachidonic acid cascade. Lysophospholipids, phosphatidylglycerol, and cardiolipin were rather cytotoxic and lacked activity, an observation suggesting that membrane perturbation is not responsible for the neurite-promoting activity. Treatment with a protein kinase C inhibitor, H-7, or an Na+,K(+)-ATPase inhibitor, ouabain, inhibited the PI-induced neurite outgrowth, but the cyclic AMP- and cyclic GMP-dependent protein kinase inhibitor HA1004 did not inhibit this activity, a result indicating that multiple elements (protein kinase C and Na+,K(+)-ATPase) are involved in the induction of neurites. Because phospholipids can be provided either as lipid vesicles or as lipoproteins produced by macrophages at regeneration sites, they may play an important role in the regeneration of certain populations of neurons.     

Restoration of High Affinity Choline Uptake in the Hippocampal Formation Following Septal Cell Suspension Transplants in Rats with Fimbria-Fornix Lesions

High affinity choline uptake (HACU) was investigated in the hippocampal formation following fetal septal cell suspension transplants into rats with fimbria-fornix lesions. Nine-14 weeks after transplantation, HACU was markedly decreased in hippocampi from animals with fimbria-fornix lesions; this decrease was ameliorated by fetal septal cells transplanted into the host hippocampus. HACU related to septal transplantation was activated in vitro by K+, and in vivo by the administration of scopolamine and picrotoxin. These findings suggest that fetal septal cell transplantation can restore HACU in the host hippocampus following fimbria-fornix lesions, and that HACU related to the graft has pharmacological properties similar to those of the normal adult HACU system. The activation of HACU by picrotoxin, a gamma-aminobutyric acid (GABA) antagonist, suggests that transplanted cholinergic neurons receive either direct or indirect functional input from GABAergic afferents from the transplant and/or host hippocampus. Lesions of the fimbria-fornix also resulted in an increased binding to muscarinic receptors in the dorsal hippocampus. This increase in binding was not significantly ameliorated by intrahippocampal grafts of cholinergic neurons.     

The fate of Taenia taeniaeformis oncospheres in normal and passively protected rats

Rats were passively protected against challenge infection with Taenia taeniaeformis by the administration of immune serum. Macroscopic liver lesions were rarely seen following challenge. The fate of oncospheres was determined by histological examination of rat livers at various intervals after infection, and also by in vitro experimentation.Oncospheres were killed soon after exposure to immune serum in vitro, but numbers reaching the liver were not significantly different in both passively protected and control rats. Oncospheral reorganisation did not take place in passively protected rats. In control rats, only 20 per cent of oncospheres reaching the liver were able to undergo reorganisation. Developing larvae also appeared to be susceptible to host rejection mechanisms, especially between days 5 and 9 after infection.     

Effects of experimental hyperadrenocorticism on the growth of the femur and tibia in normal and bipedal rats

Daily subcutaneous injections of glucocorticoid preparations have been shown to produce clinical signs of hyperadrenocorticism which resulted in interference with the growth of rats, shown by measurements both of body weight and of the length of long bones. The purpose of this study was to see if increased, intermittent, compressive forces, produced by experimental bipedalism, would mitigate the negative effects of cortisone injections on long bone growth and if there would be a difference in reaction between male and female rats. Male and female Sprague-Dawley rats were used for control, cortisone-injected, and cortisone-injected plus bipedal groups. Experimental bipedalism was produced at 10 days of age; cortisone injections began at 30 days of age; all animals were sacrificed at 65 days of age. Tibial and femoral lengths were measured. The results do not support the hypothesis that bipedalism can be instrumental in mitigating the effects of hyperadrenocorticism on hindlimb long bone growth.