Small-molecule inhibitors targeting the DNA-binding domain of STAT3 suppress tumor growth, metastasis and STAT3 target gene expression in vivo

Signal transducer and activator of transcription 3 (STAT3) is constitutively activated in malignant tumors and has important roles in multiple aspects of cancer aggressiveness. Thus targeting STAT3 promises to be an attractive strategy for treatment of advanced metastatic tumors. Although many STAT3 inhibitors targeting the SH2 domain have been reported, few have moved into clinical trials. Targeting the DNA-binding domain (DBD) of STAT3, however, has been avoided due to its 'undruggable' nature and potentially limited selectivity. In a previous study, we reported an improved in silico approach targeting the DBD of STAT3 that resulted in a small-molecule STAT3 inhibitor (inS3-54). Further studies, however, showed that inS3-54 has off-target effect although it is selective to STAT3 over STAT1. In this study, we describe an extensive structure and activity-guided hit optimization and mechanistic characterization effort, which led to identification of an improved lead compound (inS3-54A18) with increased specificity and pharmacological properties. InS3-54A18 not only binds directly to the DBD and inhibits the DNA-binding activity of STAT3 both in vitro and in situ but also effectively inhibits the constitutive and interleukin-6-stimulated expression of STAT3 downstream target genes. InS3-54A18 is completely soluble in an oral formulation and effectively inhibits lung xenograft tumor growth and metastasis with little adverse effect on animals. Thus inS3-54A18 may serve as a potential candidate for further development as anticancer therapeutics targeting the DBD of human STAT3 and DBD of transcription factors may not be 'undruggable' as previously thought.

TBX21 polymorphisms are associated with virus persistence in hepatitis C virus infection patients from a high-risk Chinese population

Hepatitis C virus (HCV) infection is a major cause of chronic liver disease and the varied outcomes of the infection depend on both viral and host factors. We have demonstrated that the HCV alternate reading frame protein (F protein) is related to Th1/Th2 bias which is involved in virus persistence in chronic hepatitis C (CHC) patients. The purpose of this study was to test the hypothesis that genetic variants of TBX21 (T cell specific T-box transcription factor) were associated with the outcomes of HCV infection and F protein generation. Three single nucleotide polymorphisms (SNPs) (rs17250932, rs2074190, rs4794067) in the TBX21 gene were genotyped in a case-control study in a cohort of a high-risk group, including 354 healthy controls and 747 CHC patients (190 anti-F protein antibody seronegative patients and 557 anti-F protein antibody seropositive patients). Results showed that the rs4794067 C allele in the TBX21 promoter was significantly more common in CHC patients (OR = 1.335, 95% CI = 1.058-1.684, P = 0.015), exceptionally in anti-F protein seropositive patients (OR = 1.547, 95% CI = 1.140-2.101, P = 0.005), compared with healthy controls. And the risk effect was also significantly high in patients with HCV 1b genotype and mild fibrosis (P = 0.021, P = 0.010, respectively). Compared with the most frequent haplotype TAT, haplotype analysis showed that the distribution of TAC was significantly different between the chronic HCV carrier group and the healthy group, and so was the anti-F antibody seronegativity group and the anti-F antibody seronegativity group (all P < 0.001). Our results suggested that TBX21 variants may be involved in the etiology of this disease.

Sonic hedgehog through Gli2 and Gli3 is required for the proper development of placental labyrinth

Sonic hedgehog (Shh) functions as a conserved morphogen in the development of various organs in metazoans ranging from Drosophila to humans. Here, we have investigated the potential roles and underlying mechanisms of Shh signaling in murine placentation. Immunostaining revealed the abundant expression of the main components of Shh pathway in both the trophectoderm of blastocysts and developing placentas. Disruption of Shh led to impaired vascularogenesis of yolk sac, less branching and malformation of placental labyrinth, thereby leading to a robust decrease in capacity of transplacental passages. Moreover, placenta-specific gene incorporation by lentiviral transduction of mouse blastocysts and blastocyst transplantation robustly knocked down the expression of Gli3 and Gli2 in placenta but not in embryos. Finally, Gli3 knockdown in Shh^−/− placentas partially rescued the defects of both yolk sac and placental labyrinth, and robustly restored the capacity of transplacental passages. Gli2 knockdown in Shh^+/− placentas affected neither the capacity of tranplacental passages nor the vascularogenesis of yolk sac, however, it partially phenocopied the labyrinthine defects of Shh^−/− placentas. Taken together, these results uncover that both Shh/Gli2 and Shh/Gli3 signals are required for proper development of murine placentas and are possibly essential for pregnant maintenance.

Single uroflow study as a tool in predicting the possibility of abnormal voiding symptoms after the administration of antimuscarinic agents in treating overactive bladder syndrome

PURPOSE OF STUDY

The aim of this study was to evaluate the efficacy of uroflowmetry in predicting the possibility of abnormal voiding symptoms following antimuscarinic treatment for overactive bladder syndrome (OAB) in Taiwanese women.

MATERIALS AND METHODS

A retrospective study was conducted on women with OAB. Forty-five women with abnormal voiding patterns shown by urodynamic study comprised the main group and 38 women with normal voiding patterns comprised the control group. All patients were prescribed two mg tolterodine once daily for one week. Follow-up on complaints of abnormal voiding symptoms was done one week later.

RESULTS

One woman in control group and 12 women in main group complained of abnormal voiding symptoms. There was a significant difference in the occurrence of abnormal voiding symptoms after antimuscarinic administration between main study group and control group (26.7 % vs 2.6 %, p = 0.02). CONCLUSIOn: Uroflowmetry is a non-invasive and simple tool to predict the occurrence of abnormal voiding symptoms after antimuscarinic use.

Endoluminal release of ureteral ligature after hysterectomy

Iatrogenic ureteral injury is a well-recognized complication of abdominal total hysterectomy. We report a case of a 57-year-old female who underwent abdominal total hysterectomy for a uterine myoma and experienced severe right flank pain postoperatively. The imaging study displayed an obstruction of the right distal ureter. Under ureteroscopy, an extraluminal ligature was released with a holmium:yttrium-aluminum-garnet laser. The stenotic segment was immediately relieved. Two months later, the intravenous urogram illustrated patency of the distal ureter with regression of right hydronephrosis. There was no recurrent hydronephrosis during 1 year of follow-up.

Mechanical endurance and in vivo radiographic analysis of a flexible, mono-unit cervical disc implant in intermediate follow-up period

AIM

The flexible artificial disc may create a system with a biomimetic structure that has the potential to tolerate dynamic motion in a way similar to a normal intervertebral disc over a long period. The objective was to evaluate the mechanical feasibility and clinical and radiological findings with a mono-unit and flexible artificial disc at intermediate-term follow-up.

METHODS

Fifty-six patients with degenerative disc disease were selected to participate in the study. They underwent discectomy with a flexible artificial disc with a mean follow-up period of 24.8 months. Outcomes were evaluated with the visual analogue scale (VAS) and Oswestry Disability Index (ODI). Mechanical endurance was evaluated by a dynamic testing.

RESULTS

Fifty one-levels and six bi-levels were included in the study (average age 41.8 years). VAS improved from 6.8 ± 2.2 to 1.5 ± 1.7 (P<0.05) and ODI improved from 43.1 ± 10.4 to 18.2 ± 10.2 (P<0.05). Disc height before mechanical testing was 8.9 mm, and decreased to 8.4 mm after six million cycles with no mechanical failure.

CONCLUSION

Our results indicate that flexible and mono-unit cervical disc provides favorable mechanical performance and clinical outcomes for at least a relatively intermediate-term follow up period. It is indicated that the flexible cervical disc maintains mobility at the level of the prosthesis that is comparable with preoperative ranges of motion. Further evaluation will be completed once long-term results have been obtained.

Thyroid hormone regulation of miR-21 enhances migration and invasion of hepatoma

Thyroid hormone (T(3)) signaling through the thyroid hormone receptor (TRα1) regulates hepatoma cell growth and pathophysiology, but the underlying mechanisms are unclear at present. Here, we have shown that the oncomir microRNA-21 (miR-21) is activated by T(3) through a native T(3) response element in the primary miR-21 promoter. Overexpression of miR-21 promoted hepatoma cell migration and invasion, similar to that observed with T(3) stimulation in hepatoma cells. In addition, anti-miR-21-induced suppression of cell migration was rescued by T(3). The Rac-controlled regulator of invasion and metastasis, T-cell lymphoma invasion and metastasis 1 (TIAM1), was identified as a miR-21 target additionally downregulated by T(3). Attenuation and overexpression of miR-21 induced upregulation and downregulation of TIAM1, respectively. TIAM1 attenuation, in turn, enhanced migration and invasion via the upregulation of β-catenin, vimentin, and matrix metalloproteinase-2 in hepatoma cells. Notably, correlations between TRα1, miR-21, and TIAM1 expression patterns in animal models paralleled those observed in vitro. In the clinic, we observed a positive correlation (P = 0.005) between the tumor/nontumor ratios of TRα1 and miR-21 expression, whereas a negative correlation (P = 0.019) was seen between miR-21 and TIAM1 expression in patients with hepatoma. Our findings collectively indicate that miR-21 stimulation by T(3) and subsequent TIAM1 suppression promotes hepatoma cell migration and invasion.

Arrested growth and spontaneous tumor regression of partially resected low-grade cerebellar astrocytomas in children

PURPOSE

The prognosis of children with low-grade cerebellar astrocytoma who have partial resection of tumor is largely unpredictable. The purpose of this study was to review the long-term outcome of such patients.

METHODS

The medical charts, imaging findings, operative notes, histopathological reports, and survival times of 12 patients with cerebellar astrocytoma were reviewed.

RESULTS

Five patients had total resection and seven had partial resection. Nine patients had grade I histology and three patients had grade II. Follow-up duration ranged from 3 to 25 years. Among the seven patients with residual tumor, five had tumor progression, one had arrested tumor growth, and one had spontaneous tumor regression. Five patients with partial resection received radiotherapy and three had malignant transformation of tumor during follow-up. Six patients, including five who had partial resection, underwent a second operation. One patient with partial resection died of pneumonia 23 years after surgery.

CONCLUSIONS

Patients with complete tumor resection had a better prognosis than patients with partial resection. For patients with partial resection, we recommend a "wait and see" policy with surveillance using MRI. The phenomenon of arrested tumor growth and spontaneous tumor regression in patients with cerebellar astrocytoma who have subtotal resection warrants further study.

Attenuation of cerebral vasospasm following experimental subarachnoid hemorrhage by the bronchodilator KMUP-3

Delayed cerebral vasospasm is a main cause of morbidity and mortality as well as poor outcome in patients following aneurysmal subarachnoid hemorrhage (SAH). In this study, the effect of the bronchodilator KMUP-3 (7-[2-[4-(4-nitrobenzene)piperazinyl]ethyl]-1,3-dimethylxanthine) on basilar artery narrowing, neurological outcome, and expression of rhoA/rho kinase II (ROCKII), rhoA, and protein kinase C (PKC) γ proteins were evaluated in a rat model of SAH. SAH was induced by double injection of autologous blood into the cistern magna on days 0 and 3. KMUP-3 was administered (0.3 mg/kg/day) by osmotic minipumps implanted subcutaneously (beginning day -3 in pretreatment group and at 1 h after the initiation of the first autologous blood injection in the treatment group). Neurological outcome was assessed by ambulation and placing/stepping reflex responses at 48 h after the second injection of autologous blood. Tissue morphology and protein expression were conducted on day 7 post-day 0 injection. Both KMUP-3 treatment regimens significantly improved neurological outcome and completely attenuated basilar artery narrowing as well as reduced the enhancement of ROCKII, rhoA, and PKCγ protein expression in rats subjected to SAH, compared with normal and untreated SAH rats. These results suggest that KMUP-3 may be a novel agent for the treatment of cerebral vasospasm following SAH.

Plasma levels of transforming growth factor-beta 1 before and after removal of low- and high-grade astrocytomas

Transforming growth factor-beta 1 (TGF-β1) has been reported to be a possible marker for a number of tumors, including brain tumors. The aim of this study was to measure the plasma levels of TGF-β1 in patients with low- and high-grade astrocytomas before and after surgery. This prospective study included 14 patients with low-grade astrocytomas and 25 with high-grade astrocytomas who underwent tumor removal and 13 controls (patients who underwent cranioplasty for skull bone defects). Plasma levels of TGF-β1 were measured in all subjects using enzyme-linked immunosorbent assay (ELISA). Receiver operating characteristic (ROC) curve analysis showed that when the level of TGF-β1 before tumor removal was ≥ 2.52 ng/ml, astrocytoma was predicted with a sensitivity of 94.9% and specificity of 100%. The mean plasma level of TGF-β1 in both the low-grade and high-grade astrocytoma groups significantly decreased after tumor removal (p<0.05); there was no significant change in TGF-β1 plasma level of the controls following surgery. Patients with high-grade astrocytomas had a significantly higher mortality rate than patients with low-grade astrocytomas (p=0.019) and significantly shorter survival (p=0.008). A positive correlation between TGF-β1 level after tumor removal and tumor volume was only found in the high-grade astrocytoma group (γ=0.597, p=0.002). The findings show that plasma TGF-β1 level was increased in patients with low-grade and high-grade astrocytoma, and that the levels significantly decreased after tumor removal in both groups. The results provide additional evidence that TGF-β1 might be useful as a tumor marker for astrocytomas.

Spin, charge and lattice couplings in Cu-deficient oxysulphide BiOCu0.94S

The electrical and magnetic properties of slightly Cu-deficient BiOCu(0.94)S are investigated using neutron diffraction, ac magnetic susceptibility, magnetization and electrical resistivity measurements. The Cu spins order in a ferromagnetic arrangement below T(C) = 250 K. An antiferromagnetic component develops below 180 K when the crystalline unit cell experiences a sharp thermal contraction upon cooling, resulting in a canted ferromagnetic spin arrangement at low temperatures. In the magnetically ordered state the electrical transport can be described using three-dimensional variable range hopping conduction. An applied magnetic field can effectively reduce the hopping barrier. Spin-charge couplings are clearly revealed when the resistivity departs from the hopping conduction and begins to increase with increasing temperatures above 250 K where the Cu spins become disordered.

Metachronous brain and intramedullary spinal cord metastases from nonsmall-cell lung cancer: a case report

A 44-year-old man had a brain tumor secondary to lung adenocarcinoma and underwent craniectomy to remove the brain tumor. After postoperative whole-brain radiation therapy, he underwent pneumonectomy followed by chemotherapy, mediastinal radiotherapy, and target therapy for lung cancer. Thirty-six months after the initial brain surgery, he suffered from neck pain and right upper limb numbness that rapidly progressed to upper extremity weakness and paralysis in 2 months. Magnetic resonance imaging demonstrated an intramedullary spinal cord lesion at the C4 level. Laminectomy and gross intramedullary tumor removal were performed. The patient's neurological function improved after the operation. Nevertheless, 4 months after the intramedullary tumor removal, he began to show multiple metastases. Unfortunately, the patient died from respiratory failure 8 months after diagnosis with intramedullary spinal cord metastasis. In this case, early diagnosis and aggressive surgical treatment combined with postoperative radiotherapy and chemotherapy might have provided this patient with a prolonged survival and better quality of life.

Cementless large-head metal-on-metal total hip arthroplasty in patients younger than 60 years--a multicenter early result

Large-head metal-on-metal total hip arthroplasty has the theoretical advantages of less wear and better range of motion than traditional polyethylene bearings and seems to be a better choice for young and active patients. We conducted a retrospective study and reported the early results of using such prostheses in 59 patients (70 hips) with a mean age of 43.1 years (range, 23-59 years) at the time of surgery. Osteonecrosis of the femoral head accounted for most diagnoses. Harris Hip Scores and hip range of motion both significantly improved (p<0.001) at an average follow-up of 32.6 months (range, 24-48 months). Only one intraoperative calcar fissure was encountered, and it was fixated by cerclage wiring; there was no infection, dislocation, or osteolysis around either the cup or the stem at the latest follow-up. A postoperative gap in the acetabular component was noted in 24 hips, with a mean depth of 1.11 mm, but this was not correlated with the functional score (p=0.291). Transient thigh pain, which resolved after 6 months, was observed in six patients but was not related to either the postoperative gap or cup inclination (p=1.000 and p=0.664, respectively). All patients resumed their original jobs and recreational activities with little discomfort. Thus far, large-head metal-on-metal total hip arthroplasty has shown excellent early results. The long-term results and the effects of metal debris and potentially elevated serum metal ion levels require further observation.

Combination of baclofen and antimuscarinics to reduce voiding difficulty in treating women with overactive bladders

PURPOSE OF STUDY

To evaluate the efficacy of baclofen in combination with antimuscarinics to treat women with an overactive bladder (OAB) with abnormal voiding patterns.

METHODS

An action research and chart review was conducted in 245 OAB women. Women were prescribed tolterodine or oxybutynin with or without baclofen after urodynamics. The complaint of voiding difficulty was followed up one week later.

RESULTS

There was a significant difference in the occurrence of voiding difficulty after antimuscarinic administration in OAB women with abnormal voiding patterns compared with normal patterns (18% vs 4.9%, respectively; p = 0.013). The clinical difference of voiding difficulty after treating with antimuscarinics between both voiding patterns disappeared after adding baclofen (abnormal voiding pattern vs normal pattern; 11.1% vs. 5.6%, respectively; p = 1.000).

CONCLUSION

Combined use of baclofen and antimuscarinic agents could reduce voiding difficulty in treating women with overactive bladders with abnormal voiding patterns.

Immune and inflammatory gene signature in rat cerebrum in subarachnoid hemorrhage with microarray analysis

Cerebral vasospasm following subarachnoid hemorrhage (SAH) has been studied in terms of a contraction of the major cerebral arteries, but the effect of cerebrum tissue in SAH is not yet well understood. To gain insight into the biology of SAH-expressing cerebrum, we employed oligonucleotide microarrays to characterize the gene expression profiles of cerebrum tissue at the early stage of SAH. Functional gene expression in the cerebrum was analyzed 2 h following stage 1-hemorrhage in Sprague-Dawley rats. mRNA was investigated by performing microarray and quantitative real-time PCR analyses, and protein expression was determined by Western blot analysis. In this study, 18 upregulated and 18 downregulated genes displayed at least a 1.5-fold change. Five genes were verified by real-time PCR, including three upregulated genes [prostaglandin E synthase (PGES), CD14 antigen, and tissue inhibitor of metalloproteinase 1 (TIMP1)] as well as two downregulated genes [KRAB-zinc finger protein-2 (KZF-2) and γ-aminobutyric acid B receptor 1 (GABA B receptor)]. Notably, there were functional implications for the three upregulated genes involved in the inflammatory SAH process. However, the mechanisms leading to decreased KZF-2 and GABA B receptor expression in SAH have never been characterized. We conclude that oligonucleotide microarrays have the potential for use as a method to identify candidate genes associated with SAH and to provide novel investigational targets, including genes involved in the immune and inflammatory response. Furthermore, understanding the regulation of MMP9/TIMP1 during the early stages of SAH may elucidate the pathophysiological mechanisms in SAH rats.

Autoimmunity against hNinein, a human centrosomal protein, in patients with rheumatoid arthritis and systemic lupus erythematosus

Centrosomes are organelles involved in the organization of the mitotic spindle and may also be the targets of autoantibodies in autoimmune diseases. Human Ninein (hNinein) is a centrosomal autoantigen that is identified by autoimmune patient sera. However, none of the hNinein-specific fragments recognized by the autoantibodies in rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) sera have been thoroughly characterized. We thus attempted to identify the fine specificity within the hNinein protein. In this study, four recombinant proteins in two isoforms of hNinein were used as autoantigens along with immunoassays as a molecular tool to investigate the prevalence of hNinein autoreactivity and its specificity in 22 RA and 32 SLE autoimmune disease sera. The data indicated a 50% higher prevalence of isoform 4 hNinein N-terminal autoantibodies in RA sera, whereas 22% of SLE patients were autoreactive to the N-terminal of isoform 4 hNinein compared to only a small percentage of autoreactive normal sera (5%). These results showed that autoepitopes on autoantigen hNinein are restricted to the N-terminal region and that a more significant proportion of RA patients exhibited centrosome reactivity.

Melittin liposomes surface modified with poloxamer 188: in vitro characterization and in vivo evaluation

Melittin liposomes surface modified with poloxamer 188 were developed, and the effect of poloxamer 188 was investigated with regard to anti-cancer effect and vascular stimulation. Melittin liposomes surface modified with poloxamer 188 at different concentrations (0%, 2%, and 5%) were prepared using the adsorption method, followed by in vitro characterization, including entrapment efficiency, zeta potential, particle size, and morphology. Subsequently, the influence of repeated freeze-thawing on the liposomes was investigated, and the effect of poloxamer 188 on the repeated freeze-thawing process was explored. Vascular stimulation effects of MLT, and MLT liposome that surface coated with or without poloxamer were all studied. Pharmacokinetics of the different MLT preparations were determined and the anticancer activity of the MLT formulations was investigated. The particle size of the liposomes gradually increased with increasing poloxamer 188 content, while the entrapment efficiency did not change significantly. After the first freeze-thaw cycle, size and PDI were both markedly reduced, entrapment efficiency rose, and there was no significant change of zeta potential. The vascular irritation caused by MLT could be reduced to an extent by encapsulation in liposome, but not completely eliminated, while liposomes coated with poloxamer 188 can effectively abolish the phenomenon. Melittin liposomes with surface modified by poloxamer exhibit enhanced bioavailability, effective anticancer activity, and reduced side effects compared with melittin solution. Poloxamer plays an important role in melittin liposomes.

Cation exchange interaction between antibiotic ciprofloxacin and montmorillonite

Exploring the interactions between antibiotics and soils/minerals is of great importance in resolving their fate, transport, and elimination in the environment due to their frequent detection in wastewater, river water, sewage sludge and soils. This study focused on determining the adsorption properties and mechanisms of interaction between antibiotic ciprofloxacin and montmorillonite (SAz-1), a swelling dioctahedral mineral with Ca(2+) as the main interlayer cation. In acidic and neutral aqueous solutions, a stoichiometric exchange between ciprofloxacin and interlayer cations yielded an adsorption capacity as high as 330 mg/g, corresponding to 1.0 mmol/g. When solution pH was above its pK(a2) (8.7), adsorption of ciprofloxacin was greatly reduced due to the net repulsion between the negatively charged clay surfaces and the ciprofloxacin anion. The uptake of ciprofloxacin expanded the basal spacing (d(001)) of montmorillonite from 15.04 to 17.23 A near its adsorption capacity, confirming cation exchange within the interlayers in addition to surface adsorption. Fourier transform infrared results further suggested that the protonated amine group of ciprofloxacin in its cationic form was electrostatically attracted to negatively charged sites of clay surfaces, and that the carboxylic acid group was hydrogen bonded to the basal oxygen atoms of the silicate layers. The results indicate that montmorillonite is an effective sorbent to remove ciprofloxacin from water.

Extracorporeal shockwave for hip necrosis in systemic lupus erythematosus

Patients with systemic lupus erythematosus (SLE) frequently received corticosteroid therapy, resulting in osteonecrosis of the femoral head (ONFH). Prior studies demonstrated the effectiveness of extracorporeal shockwave treatment (ESWT) for ONFH.. This study evaluated the effectiveness of ESWT for ONFH in patients with SLE. We studied 39 patients, including 15 patients with SLE (26 hips) and 24 controls (29 hips). To each affected hip we applied ESWT (6000 impulses at 28 kV in a single session). Patients were ambulated with partial weight bearing for 4-6 weeks. The primary endpoint was the need for hip replacement. The secondary endpoints were improvement in hip pain and function and image changes on X-ray and MRI. Patients received total hip replacement in 12% of patients with SLE and in 14% of controls (P = 0.802). There was no statistically significant difference in pain scores (0.86 vs. 0.89; P = 0.467) and function scores (89% vs. 91%; P = 0.194) between patients with SLE and controls. SLE response to ESWT for ONFH is comparable with ONFH in patients without SLE.

Dietary selection of sheep grazing the semi-arid grasslands of Inner Mongolia, China at different grazing intensities

The objective of this study was to investigate dietary selection of sheep grazing semi-arid grassland in Inner Mongolia, China, using the difference in organic matter digestibility (OMD) of herbage ingested and herbage on offer as indicator for selection. Faecal N was used as digestibility index for herbage ingested (FOMD), while OMD of herbage on offer (GOMD) was estimated from gas production obtained by the Hohenheim gas test. It was hypothesized that the difference between FOMD and GOMD is high, when grazing animals select against low quality herbage provided that herbage is abundant. In a grazing experiment, six grazing intensities (1.5, 3.0, 4.5, 6.0, 7.5 and 9.0 sheep/ha), representing light to very heavy grazing intensity for the semi-arid grassland, were compared. The amount of herbage on offer decreased with increasing grazing intensity. Independent statistical analysis of FOMD and GOMD showed that the differences between grazing intensities for both OMD determinations (FOMD: 54.0-57.3%, GOMD: 55.2-57.5%) were not significant (p > 0.05). The difference between FOMD and GOMD was not significant for grazing intensities, but varied between sampling periods from -4 to 1 percentage units. In conclusion, the lack of significance for the difference between FOMD and GOMD suggests that for the semi-arid grassland of Inner Mongolia, China, sheep did not select their feed due to a homogeneous nutritional composition of herbage on offer in 2005, regardless of grazing intensity.

Quality indicators and quality assessment in child health

Quality indicators are systematically developed statements that can be used to assess the appropriateness of specific healthcare decisions, services and outcomes. In this review, the range and type of indicators that have been developed for children in the UK and USA by prominent governmental agencies and private organisations are highlighted. These indicators are classified in an effort to identify areas of child health that may lack quality measures. The current state of health information technology in both countries is reviewed, since these systems are vital to quality efforts. Finally, several recommendations are proposed to advance the quality indicator development agenda for children. The convergence of quality measurement and indicator development, a growing scientific evidence base and integrated information systems in healthcare may lead to substantial improvements for child health in the 21st century.

The effects of strontium ranelate in Asian women with postmenopausal osteoporosis

The aim of this study was to assess the efficacy and safety of strontium ranelate in the treatment of postmenopausal women with osteoporosis in Taiwan. In this 12-month multicenter, randomized, double-blind, placebo-controlled study, 125 women with osteoporosis were randomly given either strontium ranelate 2 g daily or placebo. Lumbar spine, femoral neck, and total-hip bone mineral density (BMD) and biochemical markers of bone turnover were measured; adverse events and tolerability were recorded and assessed. Subjects treated with strontium ranelate showed significant increases in BMD of 5.9% at the lumbar spine, 2.6% at the femoral neck, and 2.7% at the total hip, while the placebo group exhibited no significant change at 12 months. Serum level of a formation marker (bone-specific alkaline phosphatase) was also significantly increased at 6 and 12 months. Thus, although the sample size and the treatment duration of this study could not show its effect of reducing osteoprotic fractures, strontium ranelate showed bone protection effects by increasing BMD and concentrations of a bone formation marker. Safety assessment revealed adverse events were mild and not significantly different from placebo.

Low-grade astrocytoma associated with abscess formation: case report and literature review

A rare case of low-grade astrocytoma associated with abscess formation occurred in a 52-year-old man presenting with Broca's aphasia. He underwent craniotomy and tumor removal under the impression of brain tumor with necrotic cystic change. Abscess accumulation within the intra-axial tumor was found intraoperatively. Literature related to brain abscess with brain tumor is reviewed, with an emphasis on abscesses with astrocytoma. We discuss the common brain tumors that are associated with abscess, pathogens that coexist with brain tumor, and the pathogeneses of coexisting brain abscess and tumor. It is very important to know how to differentiate between and diagnose a brain abscess and tumor, or brain abscess with tumor, preoperatively from clinical presentation and through the use of computed tomography, conventional magnetic resonance imaging, diffusion-weighted imaging or magnetic resonance spectroscopy.

The effect of polyethylene thickness in fixed- and mobile-bearing total knee replacements

In this paper fixed- and mobile-bearing implants were simulated using a multibody dynamic model and a finite element model to investigate the contact pressure distribution in the ultra high molecular weight polyethylene tibial bearing component. The thickness of polyethylene varied from 6.8 to 12.3 mm and the polyethylene was modelled as a non-linear material. It was found that the contact pressure on the polyethylene decreased in the fixed-bearing implant when the thickness of polyethylene increased from 6.8 to 8 and 9.6 mm, but there was little further decrease in pressure with the increase of polyethylene thickness from 9.6 to 11.0 and 12.3 mm. In the mobile-bearing implant, no increase in contact pressure on the superior surface was found with the increase in the thickness of the polyethylene; however, the contact pressures on the inferior contact surface of the thicker designs were higher than those in the 6.8 mm design. The numerical results obtained in this paper are in good agreement with published experimental test results. Moreover, the paper presents a detailed pressure distribution on the tibial bearing component during a full gait cycle.

A genome segment on mouse chromosome 12 determines maxillary growth

The primary and modifier genes that regulate normal maxillofacial development are unknown. Previous quantitative trait locus (QTL) analyses using the F2 progeny of 2 mouse strains, DBA/2J (short snout/wide face) and C57BL/6J (long snout/narrow face), revealed a significant logarithm-of-odds (LOD) score for snout length on mouse chromosome 12 at 44 centimorgan (cM). We further sought to validate this locus contributing to anterior-posterior dimensions of the upper mid-face at the D12Mit7 marker in a 44-centimorgan portion of chromosome 12. Congenic mice carrying introgressed DNA from DBA/2J on a C57BL/6J background were selected for submental vertex cephalometric imaging. Results confirmed QTLs, determining that short snout length (P < 0.05) and face width relative to snout length (P < 0.01) were present in the 44-cM region of chromosome 12. We conclude that one or more genes contributing to the shape of the maxillary complex are located near 44 cM of mouse chromosome 12.

A dynamic model of simulating stress distribution in the distal femur after total knee replacement

The aim of this study has been to develop a dynamic model of the knee joint after total knee replacement (TKR) to analyse the stress distribution in the distal femur during daily activities. Using MSC/ADAMS and MSC/MARC software, a dynamic model of an implanted knee joint has been developed. This model consists of the components of the knee prosthesis as well as the bones and ligaments of the knee. The femur, tibia, fibula, and patella have been modelled as mixed cortico-cancellous bone. The distal part of femur has been modelled as a flexible body with springs used to simulate the ligaments positioned at their anatomical insertion points.

With this dynamic model a gait cycle was simulated. Stress shielding was identified in the distal femur after TKR, which is consistent with other investigators' results. Interestingly, higher stresses were found in the bone adjacent to the femoral component peg.

This dynamic model can now be used to analyse the stress distribution in the distal femur with different load conditions. This will help to improve implant designs and will allow comparison of prostheses from different manufacturers.

Attenuation of experimental subarachnoid hemorrhage-induced increases in circulating intercellular adhesion molecule-1 and cerebral vasospasm by the endothelin-converting enzyme inhibitor CGS 26303

OBJECT

Adhesion molecules, including intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin, are important mediators of inflammation, and their levels are elevated in the serum of patients following aneurysmal subarachnoid hemorrhage (SAH). The investigators previously found that CGS 26303 is effective in preventing and reversing arterial narrowing in a rabbit model of SAH. The purpose of the present study was to examine whether levels of adhesion molecules are altered after treatment with CGS 26303 in this animal model.

METHODS

New Zealand White rabbits were each injected with 3 ml of autologous blood in the cisterna magna, and intravenous treatment with CGS 26303 (30 mg/kg) was initiated 1 hour later. The compound was subsequently administered at 12, 24, and 36 hours post-SAH. Blood samples were collected at 48 hours post-SAH to measure ICAM-1, VCAM-1, and E-selectin levels. After the rabbits had been killed by perfusion-fixation, the basilar arteries (BAs) were removed and sliced, and their cross-sectional areas were measured. Treatment with CGS 26303 attenuated arterial narrowing after SAH. Morphologically, corrugation of the internal elastic lamina of BAs was prominently observed in the SAH only and vehicle-treated SAH groups, but not in the CGS 26303-treated SAH group or in healthy controls. There were no significant differences in the levels of VCAM-1 among the four groups. The levels of E-selectin were increased in all animals subjected to SAH (those in the SAH only, SAH plus vehicle, and SAH plus CGS 26303 groups) compared with healthy controls (no SAH); however, the levels of ICAM-1 in the SAH only and SAH plus vehicle groups were significantly elevated (p < 0.001), and treatment with CGS 26303 reduced ICAM-1 to control levels following SAH.

CONCLUSIONS

These results show that ICAM-1 may play a role in mediating SAH-induced vasospasm and that a reduction of ICAM-1 levels after SAH may partly contribute to the antispastic effect of CGS 26303.

Laparoscopic myomectomy for large uterine fibroids. A comparative study

BACKGROUND

The goal of this study was to examine the safety and feasibility of laparoscopic myomectomy (LM) for the management of symptomatic intramural uterine fibroids with weight greater than 80 g as compared to those less than 80 g.

METHODS

In a prospective comparative study, 176 women with symptomatic uterine fibroids were scheduled for LM. They were divided into two groups, one with main uterine fibroid (intramural type) weight greater than 80 g and the other with fibroid weight less than 80 g. Outcome measures for the two groups were studied in terms of operation time, amount of blood loss, requirement of blood transfusion, and length of hospital stay.

RESULT

Operation time and amount of blood loss were significantly greater in the group with fibroid > or = 80 g than in the group < 80 g (121.5 +/- 58.9 min versus 79.1 +/- 28.6 min, p < 0.001; and 346.3 +/- 299.6 ml versus 123.0 +/- 89.7 ml, p < 0.001, respectively). However, there was no difference in the length of hospital stay and overall incidence of operative complications between these two groups. None of the women had any major complications. Nevertheless, 11 minor complications were noted, including two pelvic abscesses requiring a second laparoscopic treatment. There was no incidence of switching to laparatomy during the operation. Extreme intraoperative hemorrhage of more than 1000 ml occurred in 8 patients; however, all progressed to full recovery after blood transfusion. Rate of blood transfusion was significantly lower in the group with fibroid < 80 g (3.2% versus 22.1%, p < 0.001).

CONCLUSIONS

Despite the increased operation time and blood loss, LM can be safely performed in the treatment of large uterine fibroid. However, high risk of blood transfusion in these patients has to be kept in mind.

17beta-estradiol inhibits endothelin-1 production and attenuates cerebral vasospasm after experimental subarachnoid hemorrhage

Though cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) has been recognized for over half a century, it remains a major complication in patients with SAH. Clinical studies have shown that elevated levels of endothelin-1 (ET-1) are present in the cerebrospinal fluid of patients with SAH, suggesting that ET-1-mediated vasoconstriction contributes to vascular constriction after SAH. Administration of estrogen promotes vasodilation in humans and in experimental animals, in part by decreasing the production of ET-1. This study evaluated the influence of 17beta-estradiol (E2) on the production of ET-1 and cerebrovasospasm in an experimental SAH 2-hemorrhage model in rat. A 30-mm Silastic tube filled with E2 in corn oil (0.3 mg/ml) was subcutaneously implanted in male rats just before SAH induction. The degree of vasospasm was determined by averaging the cross-sectional areas of basilar artery 7 days after first SAH. Plasma samples collected before death were assayed for ET-1. The protective effect of E2 in attenuating vasospasm achieved statistical significance when compared with the SAH only or SAH plus vehicle groups (P < 0.01). Concentrations of ET-1 were higher in the SAH only and SAH plus vehicle groups than in controls (P < 0.001). Serum levels of ET-1 in the SAH plus E2 and E2 only groups were significantly lower than those in the SAH only and SAH plus vehicle groups (P < 0.001). There was no significant difference between ET-1 levels in the healthy control and SAH plus E2 groups. A significant correlation was found between the cross-sectional areas of basilar artery and ET-1 levels (P < 0.001). The beneficial effect of E2 in attenuating SAH-induced vasospasm may be due in part to decreasing ET-1 production after SAH. The role of E2 in the treatment of cerebral vasospasm after SAH is promising and is worthy of further investigation.

Prevention and reversal of vasospasm and ultrastructural changes in basilar artery by continuous infusion of CGS 35066 following subarachnoid hemorrhage

Endothelin-1, a potent vasoconstrictive peptide, has been implicated in the pathogenesis of cerebral vasospasm following subarachnoid hemorrhage (SAH). The goal of this study was to evaluate the effect of continuous intravenous infusion of a highly selective endothelin-converting enzyme-1 inhibitor, CGS 35066, on the prevention and reversal of cerebral vasospasm following SAH. New Zealand white rabbits were subjected to SAH by injecting autologous arterial blood into the cisterna magna. Infusion of CGS 35066 at dosages of 1, 3, or 10 mg/kg/ day was initiated either 1 hr and 24 hrs later in the prevention and reversal protocols, respectively. Animals were sacrificed by perfusion-fixation 48 hrs after SAH induction. The cross-sectional areas of basilar arteries were measured using computer-assisted videomicroscopy. Ultrastructural changes in basilar arteries were determined using electron microscopy. CGS 35066 significantly prevented and reversed the arterial narrowing after SAH in all three groups. The mean cross-sectional areas of arteries from animals in both the prevention and reversal protocol groups that received 10 mg/kg/day of CGS 35066 did not differ significantly from those of the healthy controls. Histological studies of the basilar artery in the 10 mg/kg/day treatment group did not show pathomorphological changes, such as corrugation of the endothelium seen at 2 days after SAH induction or vacuole formation in the endothelial cells noted in the vehicle-treated SAH group. These findings suggest that CGS 35066 is a promising therapeutic agent for the prevention and reversal of cerebral vasospasm after SAH. It also prevents the pathological changes in vascular walls due to SAH.

Characteristics and predictive factors of early-onset diarrhoea during pelvic irradiation

This study reported characteristics and predictive factors of early-onset diarrhoea in patients receiving pelvic irradiation. We retrospectively reviewed 229 patients undergoing radiotherapy alone for cervical or uterine cancer. Oral barium was taken 90 min before simulation. According to contrast medium within small intestine only or colon in simulation films, we categorised patients as normal and rapid transit groups. Small or large volume of small-bowel was also evaluated according to barium distribution of simulation films. Whole-pelvic irradiation (39.6-45 Gy/22-25 fractions) was delivered to all patients initially. We recorded the onset of diarrhoea during pelvic irradiation. The rates of early-onset diarrhoea (<10 Gy) were compared between these two groups. The incidence of diarrhoea before 10 Gy was 7% and 17% (p = 0.138) in patients with normal and rapid transit, respectively. In multivariate analysis, interaction among rapid transit, prior abdomen operation and large small-bowel volume (p = 0.019) were noted for early-onset diarrhoea. Further subgroup analysis revealed that rapid transit (p = 0.046) was a significant factor in patients with both prior abdominal operation and large small-bowel volume. The incidence of early-onset diarrhoea was as high as 40% in this particular group. Patients experiencing early-onset diarrhoea had a higher incidence of moderate to severe diarrhoea (65%) than those without early-onset diarrhoea (23%) (p<0.001). In multivariate analysis, early-onset diarrhoea was the only factor of moderate to severe diarrhoea (p = 0.001). In conclusion, rapid small-bowel transit may be predisposed to early-onset diarrhoea during pelvic radiotherapy in patients with both prior abdominal operations and large small-bowel volume. Early-onset diarrhoea is considered as a predictive factor of diarrhoea of a higher grade.

A preliminary study of a healthy-lifestyle-promoting program for nursing students in Taiwan

This pilot study evaluated the effects of a healthy-lifestyle-promoting program, taught as part of an undergraduate community health nursing course, on the physical fitness and health choices of 42 Taiwanese nursing students. A convenience sample provided quantitative indexes of physical fitness and lifestyle before and after the course. Qualitative data, in the form of student diaries, were also analyzed. The findings indicated a positive change in physical fitness, exercise, and nutrition as a result of the program. Including lifestyle programs in nursing education may help promote the long-term health of future nurses who will serve as positive patient role models.

Teriparatide vs. calcitonin in the treatment of Asian postmenopausal women with established osteoporosis

This study compared the clinical efficacy, safety, and tolerability of daily subcutaneous injections of teriparatide and salmon calcitonin in the treatment of postmenopausal women with established osteoporosis in Taiwan. This 6-month, multicenter, randomized, controlled study enrolled 63 women with established osteoporosis. They were randomized to receive either teriparatide 20 microg or calcitonin 100 IU daily in an open-label fashion. Lumber spine, femoral neck, total hip bone mineral density (BMD), and biochemical markers of bone turnover were measured, and adverse events and tolerability were recorded. The results at 6 months showed that patients using teriparatide had larger mean increases in spinal BMD than those who used calcitonin (4.5% vs. 0.1%), but the BMD changes in these two groups at the femoral neck and the total hip were not significant. There were also larger mean increases in bone markers in the teriparatide group than in the calcitonin group (bone specific alkaline phosphatase 142% vs. 37%; osteocalcin 154% vs. 23%). We conclude that teriparatide has more positive effects on bone formation than salmon calcitonin, as shown by the larger increments of lumbar spine BMD and bone formation markers, and caused only mild adverse events and no significant change in liver, kidney or hematological parameters. Compared with the published global results, teriparatide seems to be equally effective and safe to use in this Asian population.

Fracture of anterior cervical plate implant--report of two cases

Anterior cervical plate is a convenient and popular implant employed after corpectomy and bone grafting for traumatic or degenerative cervical spine disease. Although short-segment anterior cervical surgery may adequately be managed with anterior plate fixation alone, multilevel anterior cervical constructs exhibit a relatively high complication rate warranting a simultaneous posterior fusion. We report two patients undergoing two-level anterior corpectomy/fusion with a fixed anterior plate alone and exhibiting plate fracture in conjunction with pseudoarthrosis. The instrument failure was mainly attributed to pseudoarthrosis. However, improper contouring of the plate causing microstructural damage might create a weak point and contributed to this unusual hardware failure.

The Anti-Tumor Effect and Mechanisms of Action of Penta-Acetyl Geniposide

Gardenia, the fruit of Gardenia jasminoides Ellis, has been widely used to treat liver and gall bladder disorders in Chinese medicine. It has been shown recently that geniposide, the main ingredient of Gardenia Fructus, exhibits the anti-tumor effect. In this review, we discuss the anti-tumor effect and possible mechanisms of a derivative from Gardenia Fructus, penta-acetyl geniposide ((Ac)5GP). It has been demonstrated that (Ac)5GP plays more potent roles than geniposide in chemoprevention. (Ac)5GP decreased DNA damage and hepatocarcinogenesis induced by aflatoxin B1 (AFB1) by activating the phase II enzymes glutathione S-transferase (GST) and GSH peroxidase (GSH-Px). It reduced the growth and development of inoculated C6 glioma cells especially in pre-treated rats. In addition to the preventive effect, (Ac)5GP exerts its actions on apoptosis and growth arrest. Treatment of (Ac)5GP caused DNA fragmentation of glioma cells. (Ac)5GP induced sub- G1 peak through the activation of apoptotic cascades PKCdelta/JNK/Fas/caspase8 and caspase 3. Besides, p53/Bax signaling was suggested to be involved in (Ac)5GP-induced apoptosis, though its downstream cascades needs further clarified. (Ac)5GP has also been shown to inhibit DNA synthesis of tumor cells. It arrested cell cycle at G0/ G1 by inducing the expression of p21, thus suppressing the cyclin D1/cdk4 complex formation and the phosphorylation of E2F. The phosphorylation status of p53 on serine 392 correlated with the process of growth arrest. Evidences from the in vivo experiments showed that (Ac)5GP is not harmful to liver, heart and kidney. In conclusion, (Ac)5GP is highly suggested to be an anti-tumor agent for development in the future.

Superdipole liquid scenario for the dielectric primary relaxation in supercooled polar liquids

We propose a dynamic structure of coupled dynamic molecular strings for supercooled small polar molecule liquids and accordingly we obtain the Hamiltonian of the rotational degrees of freedom of the system. From the Hamiltonian, the strongly correlated supercooled polar liquid state is renormalized to a normal superdipole liquid state. This scenario describes the following main features of the primary or alpha-relaxation dynamics in supercooled polar liquids: (1) the average relaxation time evolves from a high temperature Arrhenius to a low temperature non-Arrhenius or super-Arrhenius behavior; (2) the relaxation function crosses over from the high temperature exponential to low temperature nonexponential form; and (3) the temperature dependence of the relaxation strength shows non-Curie features. According to the present model, the crossover phenomena of the first two characteristics arise from the transition between the superdipole gas and the superdipole liquid. The model predictions are quantitatively compared with the experimental results of glycerol, a typical glass former.

Induction of matrix metalloproteinase-9 in murine eosinophilic meningitis caused by Angiostrongylus cantonensis

Matrix metalloproteinases (MMP) have been implicated in the pathogenesis of various inflammatory diseases of the central nervous system. In the present study, a gelatinase was found to be induced in parasitic meningitis caused, in mice, by Angiostrongylus cantonensis. The enzyme had a molecular weight of about 94 kDa, showed maximal activity between pH 6 and pH 8, and was clearly inhibited by EDTA and 1,10-phenanthroline but not by leupeptin or phenylmethanesulphonyl fluoride. When samples of cerebrospinal fluid from the mice with meningitis were blotted with specific antiserum against gelatinase B (MMP-9), a 94-kDa immunopositive band was observed, indicating that the induced gelatinase was MMP-9. In the A. cantonensis-infected mice, immuno-histochemistry demonstrated MMP-9 within the endothelial cells lining the vascular spaces of the brain and in the leucocytes that were found, in aggregates, in the subarachnoid space. Leucocytes may play an important role in the pathogenesis of inflammatory disorders of the central nervous system.

Induced eosinophilia and proliferation in Angiostrongylus cantonensis-infected mouse brain are associated with the induction of JAK/STAT1, IAP/NF-kappaB and MEKK1/JNK signals

Eosinophilic meningitis or meningoencephalitis caused by Angiostrongylus cantonensis is endemic to the Pacific area of Asia, especially Taiwan, Thailand, and Japan. Although eosinophilia is an important clinical manifestation of A. cantonensis infection, the role of eosinophils in the progress of the infection remains to be elucidated. In this experiment, we show that A. cantonensis-induced eosinophilia and inflammation might lead to the induction of IAP/NF-kappaB, JAK/STAT1 and MEKK1/JNK signals. The phosphorylation levels of JAK and JNK, STAT1, IAP, NF-kappaB and MEKK1 protein products were significantly increased after 12 days or 15 days of A. cantonensis infection. However, no significant differences in MAPKs such as Raf, MEK-1, ERK1/2 and p38 expression were found between control and infected mice. The activation potency of JAK/STAT1, IAP/NF-kappaB and MEKK1/JNK started increasing on day 3, with significant induction on day 12 or day 15 after A. cantonensis infection. Consistent results were noted in the pathological observations, including eosinophilia, leukocyte infiltration, granulomatous reactions, and time responses in the brain tissues of infected mice. These data suggest that the development of brain injury by eosinophilia of A. cantonensis infection is associated with activation of JAK/STAT1 signals by cytokines, and/or activation of MEKK1/JNK by oxidant stress, and/or activation of NF-kappaB by increasing IAP expression.

The efficacy of therapy with albendazole in mice with parasitic meningitis caused by Angiostrongylus cantonensis

Matrix metalloproteinase 9 (MMP-9) is involved in the pathogenesis of parasitic meningitis caused by the nematode Angiostrongylus cantonensis. The present study evaluated the efficacy of albendazole therapy in BALB/c mice infected with the third stage larvae of this nematode. Albendazole showed a pronounced larvicidal activity. Eosinophil numbers significantly increased in infected mice but decreased upon administration of albendazole. Densitometric scanning indicated that albendazole reduced gelatinolytic activity detected by gelatin-substrate zymography. In the cerebrospinal fluid, albendazole reduced the lytic area intensity of the 94 kDa MMP-9 band by 46.5% within 7 days, and by 51.5% by day 14. Examination of brain tissue revealed a similar pattern of decrease (48.6% by day 7, and 53.9% by day 14). Albendazole may thus be an effective compound for the treatment of angiostrongyliasis through its larvicidal activity and facilitation of an improved inflammatory response via the reduction of MMP-9 activity.

Intramedullary nails with two lag screws

OBJECTIVE

To investigate the structural integrity of intramedullary nails with two lag screws, and to give guidance to orthopaedic surgeons in the choice of appropriate devices.

DESIGN

Alternative designs of the construct are considered, and the use of a slotted upper lag screw insertion hole is analysed.

BACKGROUND

Intramedullary fixation devices with a single lag screw have been known to fail at the lag screw insertion hole. Using two lag screws is considered. It has also been proposed to use a slot in the nail for the upper lag screw to prevent the upper lag screw from sticking.

METHODS

Bending and torsion load cases are analysed using finite element method. Consideration of both load conditions is essential.

RESULTS

The results present the overall stiffness of the assembly, the load sharing between lag screws, and the possibility for cut-out to occur.

CONCLUSIONS

While the slot for the upper lag screw might be advantageous with regard to the stresses in the lag screws, it could be detrimental for cut-out occurring adjacent to the lag screws.

RELEVANCE

Comparative analyses demonstrate that two lag screws may be advantageous in patients whose cancellous bone quality is good and who impose large loads on the lag screw/nail interface. However, the use of two screws might pre-dispose to failure by cut-out of the lag screws. The addition of a slotted hole for the upper lag screw appears to do nothing significant to reduce the risk of such a failure.

In vivo dosimetry for external photon treatments of head and neck cancers by diodes and TLDS

In vivo dosimetry was implemented for treatments of head and neck cancers in the large fields. Diode and thermoluminescence dosemeter (TLD) measurements were carried out for the linear accelerators of 6 MV photon beams. ESTRO in vivo dosimetry protocols were followed in the determination of midline doses from measurements of entrance and exit doses. Of the fields monitored by diodes, the maximum absolute deviation of measured midline doses from planned target doses was 8%, with the mean value and the standard deviation of -1.0 and 2.7%. If planned target doses were calculated using radiological water equivalent thicknesses rather than patient geometric thicknesses, the maximum absolute deviation dropped to 4%, with the mean and the standard deviation of 0.7 and 1.8%. For in vivo dosimetry monitored by TLDs, the shift in mean dose remained small but the statistical precision became poor.

Intramedullary nails: some design features of the distal end

Intramedullary nails are used to stabilise fractures of the proximal femur. The nail acts by transferring loads from the proximal fraction to the rest of the femoral shaft. The way in which this occurs depends to a large extent on the design of the distal end of the nail. This is not dissimilar to the situation with regard to load shedding (or load transfer) from the femoral component of a total hip replacement. A finite element model of a fractured femur with either a neck or a subtrochanteric fracture is set up to investigate the effects of nail length, nail distal stiffness and material stiffness on the structural behaviour of the system. Specifically what is considered is the influence of these parameters on the stress across the fracture and the normal pressure that the nail exerts on the endosteum of the femoral diaphysis. It is found that a longer nail could produce higher contact stress between the tip of the nail and the endosteum. Also, this contact stress is reduced when the distal region of the nail is made more flexible either by incorporating longitudinal slots or by using a material with a lower modulus of elasticity.

Outcome of calf deep-vein thrombosis after total knee arthroplasty

We investigated the outcome of deep-vein thrombosis (DVT) in the calf after total knee arthroplasty (TKA) in 48 patients (45 women and three men) by clinical assessment and venographic study between three and four years after surgery. The mean age of the patients was 67.2 +/- 7.7 years (52 to 85) and the mean follow-up was 42.6 +/- 2.7 months (38 to 48). The diagnosis was osteoarthritis in 47 patients and rheumatoid arthritis in one patient. There were 44 calf thrombi, four popliteal thrombi but no thrombi in the femoral or iliac regions. Of the 48 patients, 24 were clinically symptomatic and 24 were asymptomatic. Clinical examination was carried out on 41 patients, of whom 37 underwent ascending venography. Seven were evaluated by telephone interview. No patient had the symptoms or signs of recurrent DVT, venous insufficiency in the affected leg, or a history of pulmonary embolism. No patient had been treated for complications of their DVT. Thirty-six of the 37 venographic studies were negative for either old or new DVT in the affected leg. One patient had residual thrombi in the muscular branches of the veins. Our study shows that deep-vein thromboses in the calf after TKA disappear spontaneously with time. No patient developed a recurrent DVT, proximal propagation or embolisation. Treatment of DVT in the calf after TKA should be based on the severity of the symptoms during the immediate postoperative period.