The effect of callus removal on dynamic plantar foot pressures in diabetic patients.

Clinical observation suggests that neuropathic foot ulceration frequently occurs beneath plantar callosities and in areas of high dynamic shear and vertical stress underneath the foot during walking. Seventeen diabetic patients had dynamic foot pressure measurements made before and after the removal of a total of 43 forefoot plantar callosities. Peak pressures (mean +/- SE) in the treated areas were reduced by 26% from 14.2 +/- 1.0 to 10.3 +/- 0.9 kg cm-2 (p less than 0.001), with reductions at 37 of the 43 sites and in all patients. Mean heel pressures were not significantly different (5.0 +/- 0.6 vs 4.9 +/- 0.6 kg cm-2). These results suggest that callus may act as a foreign body elevating plantar pressures and that a significant reduction in pressure is achieved by local chiropody treatment.     

In vitro callus induction and plantlet regeneration of Achyranthes aspera L., a high value medicinal plant

Objective

To study callus induction from different explants (internode, leaf, root) and in vitro plantlets propagation from medicinally important plant Achyranthes aspera L.

Methods

Sterilized explants were prepared by using 0.1% HgCl₂ and 0.5% Bavistin and callus was obtained when cultured onto Murashige Skoog''s (MS) medium by using different concentrations and combination of 2,4-D, NAA, BAP, IAA, IBA with 3% sucrose and 0.8% agar. Induced callus was immediately transferred to MS medium containing at different concentrations of phytohormones for shootlets and rootlets induction respectively.

Results

Sterilization treatment of 0.1% HgCl₂ for 2-3 min and Bavistin 0.5% for 10-12 min showed the highest percentage of asepsis and survival rate. Maximum induction of callus was obtained from a combination of 2.0 mg/L 2,4-D and 0.5 mg/L NAA from leaf. Highest shootlets number (4.83±0.17) and length (3.8±0.16) cm were observed on full strength MS medium when fortified with BAP 4.0 mg/L and KIN 0.5 mg/L. Concerted efforts of BAP 2.0 mg/L and NAA 0.5 mg/L on full strength MS medium showed highest leaf number (6.77±0.94). In vitro raised shoots were allowed to root on different strengths of MS medium fortified with IAA and IBA at different concentrations. Experimentally, 3.0 mg/L IBA was enabled to induce maximum rootlets number (10.0±9.82) on full strength MS medium. Afterwards, regenerated shoots with well developed roots were successfully subjected to hardening process and were acclimatized. The survived plantlets showed 66.67% survival frequency without any morphological abnormality.

Conclusions

The results demonstrated that different explants were good source of callus induction, morphology analysis as well as indirect plantlets regeneration.     

Low-intensity pulsed ultrasound shortens the treatment time in tibial distraction osteogenesis

Purpose

Low-intensity pulsed ultrasound (LIPUS) has been used successfully to accelerate healing of fresh fractures and non-unions. It also improved callus maturation with distraction osteogenesis in animal trials. However, only few clinical studies are available to support its widespread use for the latter indication in humans.

Methods

Twenty-one patients undergoing callus distraction for posttraumatic tibial defects were randomized into two groups: the trial group (12 men; mean age 32 years) which received 20 minutes LIPUS daily during treatment and the control group (six men and three women; mean age 29 years) without LIPUS treatment. The Ilizarov ring fixator was used in all cases. Results were examined clinically and radiologically, analysing callus maturation with a computer-assisted measurement.

Results

Patients in the LIPUS group needed a mean of 33 days to consolidate every 1 cm of new bone in comparison to 45 days in the control group. The healing index was therefore shortened by 12 days/cm in the LIPUS group. This means that callus maturation was 27 % faster in the LIPUS group. The fixator time was shortened by 95 days in the LIPUS group. The overall daily increase in radiographic callus density was 33 % more in the LIPUS group than in the control group.

Conclusions

LIPUS treatment is an effective non-invasive adjuvant method to enhance callus maturation in distraction osteogenesis. With the help of this treatment, the healing time and the duration of external fixation can be reliably shortened.     

激光对香石竹愈伤组织生长和分化的影响

用一定剂量的激光处理香石竹愈伤组织能显著促进其生长和分化,其中用20 mw氦氖激光处理可使愈伤组织鲜重比对照增加170％,甩0.1w和1w氩离子激光处理可明显促进芽的分化。研究结果表明,引起上述结果的原因与光质无明显关系而与激光引起的某些特殊蛋白质的产生有关。     

Limb lengthening by diaphyseal corticotomy, callus distraction, and dynamic axial fixation. An experimental study in the ovine femur

Limb lengthening of the left femur was performed in 12 sheep, 7-8 months of age. After weakening of the cortex by drill holes, a controlled fracture was created in the diaphysis. The bone segments were fixed in reduced position using a unilateral external fixation device. The fixator was left in neutral position for 10 days postoperatively when lengthening started. By means of daily distraction at a rate of 1.0 mm once a day for 3 weeks, an average lengthening of 1.9 cm (11.9%) was obtained. Two weeks after distraction had been discontinued, distinct callus bridging of the lengthening zone was confirmed radiographically in all animals. At this time the rigid state of fixation was converted to a system allowing axial compression by loading in half the animals. The other half of the animals served as controls with the fixator remaining unchanged. The external device was left on until 5 weeks after the end of distraction. At this time the animals were killed. Both femora of all animals were tested mechanically in torsion. The average ultimate torsional strength of the elongated femur compared with control was 71% in the group with dynamic axial fixation and 65% in the control group. No significant difference in relative strength of the tested bones in the two groups was found. We conclude that intermittent axial compression by loading during consolidation had no significant effect on the bone-healing process evaluated by radiography and mechanical testing.     

四种移植材料修复兔颅骨缺损的比较研究

首次应用人脱蛋白质、人脱蛋白骨／骨形成蛋白、羟基磷灰石、ＨＡＰ／ＢＭＰ作比较，修复兔颅顶骨缺损并探讨其成骨差异。７８只大白兔被随机均分Ａ、Ｂ两组，在兔颅顶骨两侧对称各制造直径为１ｃｍ的圆形骨缺损，将按实验要求制备好的ｈ－ＤＰＢ／ＢＭＰ、ＨＡＰ／ＢＭＰ、ｈ－ＤＰＢ，ＨＡＰ分别植入Ａ组和Ｂ组兔左右骨缺损内。移植材料内的＾３５Ｓ?＾４５Ｃａ和灰量的测定结果及组织学、Ｘ光摄片检查结果表明，四种移植材料的成     

小蔓长春花组织培养的研究

在含有不含有水解乳白蛋白的８种诱导培养基中，以ＭＳ培养基添加水解乳白蛋白２ｇ／Ｌ和萘乙酸１ｍｇ／Ｌ诱导小蔓长春花愈伤组织为佳，并且以外植体叶的愈伤组织诱导率为最高，达到９０％。在含不同浓度萘乙酸的８种继代培养基中，以Ｂ５ａ培养基继代培养为好，增长倍数最高可达１４．４３。并经定性试验证明在不同继代培养基上生长的愈伤组织内均含有长春胺。     

中华贝母幼茎培养及器官与体细胞胚的发生

以中华贝母（ＦｒｉｔｉｌｌａｒｉａｓｉｎｉｃａＳ．Ｃ．Ｃｈｅｎ）初萌发幼茎为外植体，在ＭＳ培养基上用ＮＡＡ、２，４－Ｄ、６ＢＡ、Ｋｔ等四种植物激素不同组合对其进行诱导，并以ＭＳ＋ＮＡＡ１ｍｇ／Ｌ＋６ＢＡ０．５ｍｇ／Ｌ为继代培养基，进行再生小鳞茎，器官分化及体细胞胚形成的研究。结果表明：组织培养中，中华贝母再生鳞茎可通过三种方式产生。     

Characteristic molar ratios of magnesium,carbon dioxide,calcium and phosphorus in the mineralizing fracture callus and predentine

Summary From fracture callus in different stages of mineralization the contents of Mg, CO₂, Ca and P were determined and compared with those found in predentine. It was found that the Mg- and CO₂-contents are high in relation to Ca and P values during the prestages and early stages of mineralization. These relatively high Mg- and CO₂-values are connected with high Mg/Ca, Mg/P, CO₂/Ca and CO₂/P ratios which strongly decrease with the increasing degree of mineralization. These results seem to be part of a general controlling mechanism of the calcification.     

Bilaterally increased VEGF-levels in muscles during experimental unilateral callus distraction.

Angiogenesis is essential for wound healing and proliferative processes such as bone formation and repair. Since increased expression of the vascular endothelial growth factor (VEGF) stimulates bone formation, it can be hypothesized that surgical procedures leading to a systemic increase of VEGF for instance during wound healing, influence enchondral ossification processes and might be responsible for observed growth phenomena during callus distraction. To study the mechanisms of angiogenesis in soft tissue during unilateral callus distraction, lengthening of the right tibia was performed in 12 beagles. After osteotomy, application of a ring fixator and after five latency days, distraction was started for 25 days. A control group of four additional beagles underwent no surgical procedure. Subsequent to the distraction period (Group A), muscle samples from six beagles were taken from the distracted side (ds) and the contralateral non-distracted side (n-ds), six beagles underwent an additional consolidation period of 25 days (Group B). Samples were analyzed for VEGF, VEGFR-1 and VEGFR-2 mRNA expression using real-time PCR and protein expression using Western Blot analysis. Muscles from both extremities showed significantly increased expression of VEGF and its cognate receptors VEGFR-1/2. Expression decreased significantly after the consolidation period, whereby the level at the non-distracted side decreased more than the level at the distracted side. Interestingly VEGF and VEGFR-1 levels at the non-distracted side were significantly higher than at the distracted side. In contrast VEGFR-2, the receptor that mediates endothelial cell proliferation, showed higher levels at the distracted than at the non-distracted side. These findings indicate that callus distraction results not only in locally increased expression of VEGF and its receptors, but leads also to increased VEGF and VEGFR-1/2 levels at distant sides and might therefore be responsible for the observed growth phenomena during callus distraction.