Use of a CEPH meiotic breakpoint panel to refine the locus of limb-girdle muscular dystrophy type 1A (LGMD1A) to a 2-Mb interval on 5q31

BACKGROUND: Cortical reaming and intramedullary nail insertion injure the medullary vascular system. Little attention has been directed toward quantitative assessment of bone injury and repair after locked intramedullary nailing of long-bone fractures with and without reaming. The effects of reamed versus unreamed locked intramedullary nailing on cortical porosity and new bone formation were compared in a sheep fractured tibia model. METHODS: After creation of a standardized spiral fracture by three-point bending with torsion, each tibia was stabilized by insertion of a locked intramedullary nail. Ten sheep were randomized into two groups, one that had reaming before nail insertion and one that did not. Fluorochromes were given 2 weeks (xylenol orange), 6 weeks (calcein green), and 12 weeks (tetracycline) postoperatively. All animals were killed at 12 weeks postoperatively. Cortical porosity and new bone formation were determined for the proximal diaphysis, fracture site, and distal diaphysis. RESULTS: Overall cortical porosity was greater with reamed nails than with unreamed nails (p = 0.02). Porosity in the inner cortex (18.3% (reamed) vs. 14.3% (unreamed); p = 0.09) and outer cortex (16.8% (reamed) vs. 12.2% (unreamed); p = 0.04) was greater in the reamed group. With reamed nails only, there was less new bone formation at 2 (p = 0.04) and 12 (p = 0.05) weeks in the inner cortex compared with the central cortex and outer cortex. Overall, there was no difference between reamed and unreamed nails in the amount of new bone formation at 2, 6, or 12 weeks. CONCLUSIONS: This study demonstrates that greater injury or overall cortical porosity is associated with reamed nail insertion. There is no difference, however, between the amount of new bone formation after reamed and unreamed nail insertion. Nail insertion without reaming may be initially advantageous when tibial cortical vascularity is compromised, by limiting further injury to cortical bone. This may be important with open tibial fractures in which there is a significant risk of infection after injury. Between 2 and 12 weeks after injury, neither reamed nor unreamed nail insertion seems to have a significant advantage with respect to the amount of new bone formation that occurs.     

Changes in blood polyamine levels following chemotherapy in patients with invasive urinary bladder carcinoma

1. A range of bone structural and strength characteristics was determined in laying hens at 15, 25, 50 and 70 weeks of age. The birds were fed up to 25 weeks on diets supplemented with additional vitamin K (10 mg menadione/kg) or ascorbic acid (250 mg/kg) or up to 70 weeks on diets containing limestone in powder or particulate form. 2. There were important effects of age on all bone characteristics. Between 15 and 25 weeks there was a rapid loss of cancellous bone and a rapid accumulation of medullary bone in the proximal tarsometatarsus (PTM). These changes continued at a slower rate up to 70 weeks. Cancellous bone content of the free thoracic vertebra (FTV) also declined after 15 weeks. 3. Breaking strengths of tibia and humerus did not change between 15 and 25 weeks but decreased later in lay. 4. None of the nutritional treatments affected bone characteristics at 15 weeks of age. 5. Increasing the dietary vitamin K supplement from 2 to 12 mg menadione/kg increased cancellous bone volume in the PTM at 25 weeks. 6. Dietary ascorbic acid did not affect any of the bone characteristics measured up to 25 weeks. 7. Particulate limestone resulted in a smaller loss of cancellous bone between 15 and 25 weeks and increased accumulation of medullary bone in the PTM. Breaking strength of the tibia and radiographic densities of tibia and keel were also improved. 8. It is concluded that patterns of bone loss over the lifetime of laying hens vary, depending upon the bone type. Feeding a particulate source of calcium can help to alleviate some of the characteristics of osteoporosis. Supplementation with extra vitamin K may also be beneficial.     

Difficulty in removal of certain intramedullary nails

Intramedullary nailing is the most common treatment for displaced diaphyseal fractures of the femur and tibia. Gerhard Küntscher introduced the technique of intramedullary nailing to clinical practice in the 1940s, and this method has been the focus of many authors with regard to indications, technique, complications, and outcome. The five cases presented here represent a complication not often reported in recent years: the difficulty in removing an intact intramedullary nail. Inspection of the interlocking nails in four of the cases presented reveals a specific design characteristic: the cross sectional design of the nail prevents the distal, unslotted end of the nail from being extracted from the medullary cavity. This problem is preventable by a change in nail design or the development of absorbable implants.     

Effect of limited and standard reaming on cortical bone blood flow and early strength of union following segmental fracture

OBJECTIVE: To quantitatively determine the extent to which limited and standard intramedullary reaming disrupts cortical circulation and to evaluate the effect on the biomechanical properties of the united fracture. DESIGN: Midshaft tibial osteotomies to create a 2.5-centimeter segment of diaphyseal bone were performed in ten adult dogs. Before insertion of a locked intramedullary nail, the tibia was reamed to either 7.0 millimeters (n = 5) or 9.0 millimeters (n = 5). Blood flow was measured using laser Doppler flowmetry during the nailing procedure and at eleven weeks postnailing. Bending stiffness and load to failure were determined for each healed tibia. RESULTS: Tibial blood flow was reduced for the limited and the standard ream groups by 63 percent (p = 0.002) and 83 percent (p = 0.0008), respectively. After canal reaming, perfusion was reduced to a greater extent in the standard ream group (p = 0.009). At eleven weeks postnailing, tibial perfusion increased to the same levels in both groups (p = 0.43) and returned to base-line values. Bending stiffness and load to failure were reduced after limited reaming (p = 0.002, p = 0.003) and standard reaming (p = 0.01, p = 0.002) were performed. Stiffness and load to failure were reduced to the same extent in both groups (p = 0.12, p = 0.25). CONCLUSIONS: Both limited reaming and standard reaming negatively affect diaphyseal cortical circulation. Limited reaming spares cortical perfusion compared with standard reaming at the time of nail insertion. No long-term advantage for limited reaming was demonstrated. Limited reaming may be advantageous acutely for the stabilization of tibial fractures in which the circulation is already compromised.     

Healing of tibial fractures is not impaired after acute hindlimb ischemia in rats

The influence of transient circulatory arrest on the healing of closed tibial fractures was investigated in rats by the use of a hindlimb tourniquet technique. Twenty-four animals were randomly divided into three groups. In all animals, the left lower leg was fractured and fixed with an intramedullary nail system. In the ischemic group, complete acute transient ischemia for 4.5 h and neurapraxia of the sciatic and femoral nerves were induced prior to fracture. In the neurapraxia group, the sciatic and femoral nerves were crushed with forceps before fracture. In the control group, no other intervention than fracture was made. The rats of the control group ambulated normally 3-4 days after the operation. The animals of the ischemic and neurapraxia groups resumed normal weight-bearing after about 3 weeks. After 6 weeks, all animals were killed, and mechanical strength and bone mineral turnover of the healing tibia as well as blood flow of the bone and musculature were evaluated. The weight of the tibia and the corresponding anterior tibial muscle in the ischemic and neurapraxia animals were reduced compared with the control rats. Bone mineral turnover was found to be lower in the ischemic group. There were no differences between the groups in mechanical strength nor in blood circulation of bone and muscle. In conclusion, complete, acute hindlimb ischemia for 4.5 h in rats did not cause delayed healing of closed tibial fractures.     

Inhaled nitric oxide therapy for pulmonary disease in pediatrics

Prostaglandin E2 (PGE2) is an anabolic agent of bone in vivo but the mechanism of its action still remains unclear. The aim of this study was to determine whether the effect of PGE2 on skeleton is mediated by pituitary hormones. Forty female, Sprague-Dawley rats were divided into four groups: baseline control (basal), age-matched intact control (CON), hypophysectomy (HX), and HX + PGE2 (2 mg/kg/day) with 10 animals in each group. The basal group was sacrificed at 2 months of age, and the remaining groups after 6 weeks of treatment. Cancellous and cortical bone histomorphometry was performed on double fluorescent-labeled 40 micron-thick sections of the proximal tibia and tibial shaft. Our results show that HX resulted in a cessation of bone growth, a decrease in cancellous bone volume, and cortical bone gain compared with the age-matched, intact CON rats. Compared with the HX group, the HX + PGE2 group had a significantly greater tibial bone density (mean +/- SE, HX + PGE2:1.595 +/- 0.007 versus HX:1.545 +/- 0.013), percent cancellous bone volume (21.4 +/- 2.0 versus 8.41 +/- 1.70), percent cortical bone area (87.2 +/- 0.85 versus 81.7 +/- 0.7), and ratio of cortical area to marrow area (7.14 +/- 0.56 versus 4.52 +/- 0.21). Increased bone masses by PGE2 in the HX animals were accompanied by an increase in the trabecular and endosteal-labeled surface and bone formation rate. The trabecular number and width were increased whereas trabecular separation was decreased in the HX + PGE2 group compared with the HX group (P < 0.05). PGE2 treatment also caused a decrease in the tibial endosteal eroded surface and medullar cavity of the HX animals. In conclusion, this study clearly demonstrates that PGE2 (2 mg/kg/day) in the HX rats increases both cortical and cancellous bones and improves trabecular architecture in the tibia after 6 weeks of treatment. These skeletal alterations are due to a stimulation of bone formation and a suppression of bone resorption activity. These findings suggest that the anabolic effect of PGE2 in bone is independent of pituitary hormones.     

In times of survival, the right of silence

The purpose of this study was to assess cortical and cancellous bone responses to unilateral limb immobilization and, subsequently, to remobilization with exercise, in a young adult canine model. Right forelimbs of 14 1-2-year old mongrel dogs were immobilized in a non-weight-bearing position by a bandage for 16 weeks. Six control dogs were untreated. At 16 weeks, seven immobilized and three control dogs were euthanized. The remaining seven immobilized dogs began a recovery protocol consisting of 16 weeks of kennel confinement (without the right forelimb bandaged) followed by 16 weeks of treadmill exercise conducted three times per week. These seven dogs and three control dogs were euthanized at 48 weeks. Bone mineral density of the proximal radii was determined with dual-energy X-ray absorptiometry and humeral middiaphyseal cross-sectional areas were determined with computed tomography. Humeri were tested in cranio-caudal three-point bending to failure. Cancellous bone cores from the lateral humeral condyles had wet apparent density determined and were tested to failure in compression. Mechanical properties, bone density, and cross-sectional areas were compared between immobilized (right forelimb), contralateral weight bearing (left forelimb), and control forelimbs with Kruskal-Wallis and post hoc tests. At 16 weeks, bone mineral density, cortical load, yield, and stiffness as well as cancellous bone failure stress, yield stress, and modulus were significantly lower (p < 0.02) for immobilized limbs than control limbs. Immobilized limb cancellous bone mechanical properties were 28%-74% of control values, and cortical bone mechanical properties were 71%-98% of control values. After 32 weeks of remobilization, cortical and cancellous bone mechanical properties were not different from control values except that cortical bone failure stress and modulus were significantly higher (p < 0.01) between remobilized and control limbs. In summary, 16 weeks of forelimb immobilization was associated with significantly lower mechanical properties, and with greater differences in cancellous than cortical bone properties. Mechanical properties were not different from control values after 32 weeks of recovery that included 16 weeks of treadmill exercise.     

Dysbaric osteonecrosis in divers and caisson workers. An animal model

Dysbaric osteonecrosis was induced successfully in adult sheep after 12 to 13, 24-hour exposures to compressed air (2.6-2.9 atmospheres absolute) during a 2-month period. All exposed sheep had decompression sickness and extensive bone and marrow necrosis in their long bones. Radiographic analysis of these progressive lesions showed mottled to distinct medullary opacities and endosteal thickening characteristic of dysbaric osteonecrosis. Six months after the last hyperbaric exposure, neovascularization of once ischemic fatty marrow was centripetal from the diaphyseal cortex. Proliferating endosteal new bone, fatty marrow calcification, and appositional new bone formation were widespread. Juxtaarticular osteonecrosis involved marrow fibrosis and loss of osteocytes in subchondral cortical bone. Tidemark reduplication in juxtaarticular bone and cartilage thinning suggested possible early osteoarthritis induction by recurrent episodes of transient ischemia after multiple hyperbaric exposures. Dysbaric osteonecrosis appears to involve a bone compartment syndrome of elevated intramedullary pressure initiated by decompression induced N2 bubble formation in the fatty marrow of the long bones. An animal model that can be used to investigate the pathogenesis, diagnosis, and treatment of dysbaric osteonecrosis is discussed.     

Retrograde intramedullary nailing of femoral diaphyseal fractures

OBJECTIVES: To prospectively evaluate the results of retrograde intramedullary nailing of femoral shaft fractures. DESIGN: Prospective, consecutive series. PATIENTS AND SETTING: All patients with a femoral shaft fracture admitted at an urban Level 1 trauma center from December 1995 to December 1996 were treated with a retrograde femoral intramedullary nail. INTERVENTION: Retrograde femoral intramedullary nailing was performed on a radiolucent operating room table. Through a three-centimeter medial parapatellar incision, a reamed ten-millimeter retrograde nail was inserted. METHODS: From the time of injury until union, the following parameters were assessed: operative time, blood loss, extent of comminution, open grade, associated injuries, Injury Severity Score, body mass index, time to union, secondary procedures, range of motion in the knee. and complications. RESULTS: Fifty-seven patients with sixty-one fractures were available for follow-up, which averaged 43.1 weeks. Fifty-two percent of fractures demonstrated Winquist Type 3 or 4 comminution. Twenty-six percent of the fractures were open. Fifty-two fractures healed after the initial nailing, five of seven dynamized nails healed, and one patient with bone loss requiring bone graft united yielding a final union rate of 95 percent. Of the three nonunions (5 percent), two healed with exchange nailing and one remains asymptomatic at seventy-one weeks. One patient developed a late septic knee that resolved with treatment. Excellent range of motion in the knee was obtained by those patients who did not have other ipsilateral limb injuries. CONCLUSIONS: This consecutive series had a 95 percent union rate after nailing and dynamization as necessary. No knee problems were associated with the retrograde femoral intramedullary nailing technique. The one septic knee raises concerns about the use of retrograde nailing in severe open femoral shaft fractures. Retrograde femoral nailing should be given serious consideration as an alternative to antegrade femoral nailing.     

Allergic and Irritant Glove-related Diseases in Health Care Workers and Their Prevention

A simulation study of distal interlocking of an intramedullary nail was performed using newly devised, portable stereo fluoroscopy. Two intramedullary nails in which ten holes were drilled perpendicular to the long axis and at various angles to the diameter were inserted into a femoral and a tibial bone model. Ten drill bits were drilled freehand into the holes in the nail with the aid of the stereo fluoroscope. All twenty drill bits were seated in the holes in the first attempt. This instrument provides a three-dimensional view in real time, which enables the surgeon to appreciate the three-dimensional relationship between the drill bit and the hole in the nail in the bone model. Distal interlocking of the intramedullary nail is facilitated with the aid of this stereo fluoroscope.     

Focus on managed care. Organizational structure: sequelae for patients and physicians]

The thermal degradation of plasmid pUC18 held at temperatures between 100 and 135 degrees C was examined by measuring the ability of heat-treated plasmid preparations to transform Escherichia coli to ampicillin resistance using electroporation. Substantial protection against loss of transforming ability during heating was provided by concentrations of NaCl between 0.25 and 2.0 mol l-1. For example, the addition of 1.0 mol l-1 NaCl to samples heated at 100 degrees C for 15 min increased transformation frequency about 200-fold compared with samples heated without NaCl. In the presence of 0.5-2.0 mol l-1 NaCl, transforming capacity was not destroyed even by heating at 121 degrees C for 15 min, i.e. after a typical sterilization treatment. These findings may have implications for the safe disposal of genetically modified micro-organisms and recombinant DNA preparations.     

Management of small infected tibial defects with antibiotic-impregnated autogenic cancellous bone grafting

Between January of 1991 and December of 1993, 36 patients who had tibia fractures complicated by small infected tibia defects were treated at the authors' service. The group included 30 men and 6 women whose average age was 36.5 years (range, 18-72 years). The average follow-up period was 3.7 years. By using the Cierney-Mader staging classification of chronic osteomyelitis, 26 of 36 patients (72%) were stage 4A and 10 of 36 patients (28%) were stage 4B. Ten patients required muscle transfer. All patients were treated with a two-stage protocol. In the first stage, antibiotic-impregnated polymethylmethacrylate bead chains were used to obliterate the debrided osseous defect. In the second stage, the beads were removed, and the defects were reconstructed with antibiotic-impregnated autogenic cancellous bone graft. The time between the first and second stage was 2 to 8 weeks for patients without muscle transfer and 8 to 12 weeks for the patients with muscle transfer. The bone defects ranged from 2 to 4 cm. Wound healing and bony union were achieved in all patients. Only two patients had recurrent infections. The infection arrest rate was 94.4%. Minor pin tract infection of the external skeletal fixation was seen in two patients. Two patients developed skin rashes secondary to antibiotic therapy. Radiographs at an average follow-up of 3.7 years showed good consolidation and hypertrophy of grafted bones in all patients. After 3 to 5 years of follow-up, our results suggest that the use of impregnating antibiotics have no adverse effects on autogenic cancellous bone graft incorporation and may help to eliminate infection. This treatment protocol provided rapid recovery from osteomyelitis. The use of antibiotic-impregnated autogenic bone graft seems to be an effective and safe method for the management of small infected tibial defects.     

Supplementation of coconut oil from different sources to the diet induces cellular damage and rapid changes in fatty acid composition of chick liver and hepatic mitochondria

PURPOSE OF THE STUDY: Impaction in pertrochanteric fracture sites is a well known phenomenon; the screw-plate system is designed to stabilise the fracture. Although easier to use, the risk with the nail-plate system is postoperative penetration of the nail into the joint. The present study was conducted to determine the exact conditions of the impaction, and to identify possible ways to improve the nail-plate system. MATERIAL-METHOD: The study included 129 cases of pertrochanteric fracture, excluding sub-trochanteric fractures. All fractures were fixed with a 130 degrees angulated nail-plate. In all cases, consolidation was uneventful after 8 to a 12 weeks. The anatomical type of fracture, i.e. stable or unstable, was determined according to the size of the intermediary fragment, including the trochanter minor. The displacement was measured as the difference between the length of the nail and the length of the femoral head and neck measured along the axis of the femoral neck. The parameters examined were: fracture stability degree, bony mineralisation (Singh Index), nail length, femoral neck, length nail position in the femoral head, and above all, fracture reduction. All these parameters were computerised and compared using Stat View statistics software. RESULTS: Impaction was observed in 43 per cent of cases. Among these, 25 per cent were rated as slight (1 to 5 mm), 18 per cent as moderate (over 5 mm) and 9 per cent as marked (10 to 25 mm). Impaction was associated with demineralisation of the bone tissue (p = 0.001). The anatomical classification of the fracture was not a determining factor (p = 0.19), as marked displacements were also recorded in stable fractures. A posterior and inferior position of the intramedullary nail in the femoral head is one of displacement determining factors (p = 0.004, two-sided 1 test). Valgus over-correction is the most important factor, especially when it is associated with bony demineralisation (p = 0.02) and an inadequately centred intramedullary pin (p = 0.02). Shorter the femoral neck, and shorter the nail, greater was the frequency of nail articular penetration. DISCUSSION: The risk of articular penetration therefore reaches 15 per cent in petrochanteric fractures repaired with a nail plate, set at an angle of 130 degrees. A short neck, a cervicodiaphyseal angle superior to 140 degrees, and demineralisation are the three determining parameters. Stable or unstable fracture has in fact little effect on displacement incidence, and therefore does not, on its own, warrant the use of a prosthesis in comminuted fractures. The authors compared their results to literature on progressive sliding system: the incidence of complications associated with this type of fracture treatment is identical, but the determining parameters are different. CONCLUSION: The study shows that the nail-plate is efficient and provides simple and solid fracture fixation. However, this osteosynthesis material needs to be modified in order to improve its fixation in the femoral head.     

Protein synthesis blockade differentially affects the stress-induced transcriptional activation of neuropeptide genes in parvocellular neurosecretory neurons

A method of orienting the femoral and tibial bone cuts relative to the endosteal cortex of the femur and tibia was used in 32 patients who underwent revision total knee arthroplasty. The mean orientation of the femoral component was 96.74 degrees +/- 1.03 degrees, mean orientation of the tibial baseplate was 90.71 degrees +/- 1.10 degrees, mean anatomic tibiofemoral alignment was 7.42 degrees +/- 1.69 degrees of valgus, and mean mechanical tibiofemoral alignment was 1.09 degrees +/- 1.83 degrees of valgus. Mean tibial bowing was 1.63 degrees +/- 1.57 degrees of valgus, and mean femoral bowing was 0.58 degrees +/- 1.53 degrees of varus. Valgus tibial bowing was correlated with valgus orientation of the tibial component (r = .86, P < .000001), and varus femoral bowing was correlated with orientation of the femoral component (r = .54, P = .0054). Referencing the implant position from the endosteal cortex of the intramedullary canals provides a reliable method of achieving satisfactory alignment in most revision total knee arthroplasties; however, bowing of the femur or tibia can affect alignment.     

Changes of bone-perfusion in osteosynthesis of the femur with a marrow-nail (author's transl)

The perfusion of the bone in the hind leg after osteosynthesis (nailing of the bone-marrow) was studied. In 11 shepherd dogs (bastards) an osteotomy of the femur was done; it was treated with a marrow-nail without boring the marrow-cavity. With the "tracer-microsphere"-method the perfusion of femur, tibia and talus of both hind legs was measured. Measurements were performed before and after surgery, in 10 dogs 2 weeks and in 8 dogs 6 weeks after surgery. Immediately after the operation the perfusion was reduced considerably in all the examined bones of the operated leg. Two weeks later the perfusion was increased in all bones of both hind limbs. In the cancellous bone of the femur the perfusion reached the original preoperative values after 6 weeks; in cortical bone a further increase of the perfusion was noted. This increase was most marked in the cortical bone of the operated femur; it was less in the cortical bone of the other bones.     

Forces required to initiate sliding in second-generation intramedullary nails

Second-generation intramedullary nails, which allow the fixation screw that is placed in the femoral head to slide distally and thus allow compression of the fracture of the femoral neck, have become a popular option for the treatment of ipsilateral fractures of the femoral neck and shaft. However, the sliding characteristics of the screw within the barrel of the nail or the side-plate have not been assessed biomechanically, to our knowledge. The goal of the current study was to investigate the forces required to initiate sliding of the proximal screw in intramedullary devices and to compare these forces with those required to initiate sliding of hip screws. The loading configuration simulated the typical angle of 135 degrees between the intramedullary nail and the proximal screw. The forces required to initiate sliding of the proximal screw, with the screw extended fifty-one, seventy-six, eighty-six, and 102 millimeters beyond the proximal end of the barrel, were measured for three different types of second-generation intramedullary nails (Recon, ZMS, and Gamma), a sliding compression hip screw, and an intramedullary hip screw, and these forces were then compared. With each amount of extension of the screw, the hip screws required lower forces to initiate sliding than did the second-generation intramedullary devices. Of the second-generation devices, the Gamma nail required the highest forces to initiate sliding; the Recon and ZMS nails required 20 to 40 percent lower forces compared with the Gamma nail. None of the devices jammed in any of the loading configurations that were tested. When the extension of the screw was increased, higher forces were required to initiate sliding.     

Variations in tumour oxygen tension (pO2) during accelerated radiotherapy of head and neck carcinoma

The study was performed to assess the effect of accelerated radiotherapy on oxygenation of primary tumours and metastatic nodes in patients with advanced head and neck tumours. In 14 patients with head and neck tumour, oxygen tension (pO2) was evaluated in normal tissues and tumours (primary tumour or metastatic neck node) before (0 Gy) and after 2 weeks (32 Gy) of accelerated radiotherapy (70 Gy in 3.5 weeks, with three daily fractions). Radiotherapy was combined with carbogen breathing in 5 patients. pO2 was measured using a polarographic technique. For pooled normal tissues, median pO2 was 38 mmHg before treatment and 46 mmHg after 2 weeks. For tumours, very low values (< 2 mmHg) represented 20% of the recorded values before treatment and 10% after 2 weeks. The relative increase in tumour oxygenation was more pronounced for primary tumours (median pO2 12 mmHg before treatment versus 26 mmHg after 2 weeks, P < 0.05) than for metastatic nodes (respectively, 20 and 27 mmHg P = 0.1). For the 5 patients who breathed carbogen during accelerated radiotherapy, the median pO2 was 44 mmHg at 2 weeks, compared with 13.5 mmHg before treatment (P = 0.05). Very low pO2 values, corresponding to tumour hypoxia, were found in the tumours (primary and metastatic neck nodes) prior to accelerated treatment. During the first 2 weeks of accelerated treatment, an increase in median pO2 was found in nine of the 14 tumours, together with a decrease in the frequency of very low values.     

Detection and sequence diversity of Kaposi's sarcoma-associated herpesvirus (KSHV)/human herpesvirus 8 (HHV-8) DNA

OBJECTIVE: To determine the patellofemoral contact areas as well as mean and maximal pressures after retrograde intramedullary nailing in a cadaveric model. STUDY DESIGN: Pressure-sensitive film was used to analyze patellofemoral joint pressures after insertion of a retrograde femoral nail in a cadaveric specimen. METHODS: A retrograde femoral nail was inserted into seven cadaveric knees. Pressure-sensitive film was placed into the patellofemoral joint and physiologic loads (700 newtons) were applied to the knee joint at 90 degrees and 120 degrees of flexion. Testing was performed with the nail three millimeters deep to the cartilage (In), flush with the cartilage (Flush), and one millimeter prominent (Out). The intact knee served as the Control. RESULTS: The mean contact areas showed no statistical differences among the four groups. There was a significant increase in mean pressure at 120 degrees and maximum pressure at 90 degrees and 120 degrees for the Out group when compared with the Control, In, and Flush groups (p < 0.001). CONCLUSIONS: There were no significant differences in mean contact pressure, contact area, or maximum pressure among the Control, three-millimeter insertion depth, or flush insertion groups. There was, however, a significant increase in mean and maximum pressures with the nail one millimeter prominent. These results indicate that placement of a retrograde femoral intramedullary nail is critical, but that proper placement should not significantly influence the biomechanics of the patellofemoral joint.     

Epidermal growth factor receptor ectodomain in the urine of patients with squamous cell carcinoma

Female Sprague-Dawley rats were ovariectomized (OVX) or sham-operated at 3 months of age and maintained untreated for 1 year after surgery. Baseline control and OVX rats were killed at the beginning of treatment when the rats were 15 months of age and 1 year postovariectomy. The remaining rats were treated with hPTH 1-34 (80 micrograms/kg BW, 5 days/week) or vehicle for 10 weeks. Quantitative bone histomorphometry was performed on undecalcified longitudinal sections of the proximal femur from each rat. Baseline OVX rats exhibited cancellous and cortical osteopenia at the femoral neck as their mean cancellous bone volume and cortical width were significantly decreased compared to the means for baseline control rats. In addition, baseline OVX rats had increased osteoblast and osteoclast surfaces and a greater cancellous bone formation rate than baseline control rats. OVX rats remained osteopenic with no further bone loss from the femoral neck after 10 weeks of vehicle treatment. In contrast, cancellous bone volume and cortical width in OVX rats treated with PTH were increased to the level of vehicle-treated control rats. The hormone restored lost bone in the femoral neck of OVX rats by markedly stimulating both cancellous and cortical bone formation. These histomorphometric findings in concert with recent biomechanical studies of bone strength indicate that the femoral neck of aged OVX rats is a promising sample site for studies of the prevention and treatment of bone loss induced by estrogen depletion.     

Pathological changes in levels of three small stress proteins, alphaB crystallin, HSP 27 and p20, in the hindlimb muscles of dy mouse

The authors analyse 5 cases of gunshot wounds involving limbs with a diaphyseal fracture of the radius and ulna: 3 of the cases concern the radius and ulna and the remaining 2 involve the tibial bone. These wounds were encountered in civilian practice (3 rixes, 2 gun-shot injuries). In all of the cases, the emergency treatment consisted of extensive debridment, bone fixation by intramedullary nailing in most cases, cancellous iliac bone grafting in 2 cases, cover with a Latissimus dorsi free flap in 1 case. In all of the cases, development was free of infections bone union time was 3 to 12 months; last functional results were satisfactory.