Early outcomes of proximal humerus fracture fixation with locking plate and intramedullary fibular strut graft

Proximal humerus fractures are commonly encountered in elderly patients. Surgical treatment demonstrates high complication rates, including varus construct collapse and screw cutout. In this study, the authors evaluate the clinical outcome of locking plate fixation with intramedullary fibular strut graft augmentation as a primary surgical treatment in the prevention of early collapse and screw cutout. A total of 9 patients were evaluated. Surgery was performed for displaced proximal humerus fractures between April and December 2011. Patients were either class 2, 3, or 4, according to Neer classification. Mean patient age was 75.4 years. Preoperative and immediate, 6-week, and 3-month postoperative radiographs were evaluated. Head-shaft angles were measured to assess for varus collapse and displacement. Range of motion, complication rates, and functional recovery were also evaluated. Patients underwent open reduction and internal fixation with placement of an intramedullary fibular strut graft. Fixation was achieved with a Philos plate (Synthes, Oberdorf, Switzerland). Reduction and fixation were evaluated with radiographs. Passive exercises and range of motion were allowed immediately postoperatively, and all patients achieved active abduction and forward flexion 6 weeks postoperatively. Shoulder radiographs taken 12 weeks postoperatively revealed no loss of reduction or screw cutout. The introduction of the locking plate has improved outcomes. The addition of an intramedullary strut graft has shown improved preliminary results. Maintained reduction was observed in all 9 patients in the early postoperative period, and good functional motion was achieved. No incidence of screw cutout was recorded.

FZD7 drives in vitro aggressiveness in Stem-A subtype of ovarian cancer via regulation of non-canonical Wnt/PCP pathway

Ovarian cancer (OC) can be classified into five biologically distinct molecular subgroups: epithelial-A (Epi-A), Epi-B, mesenchymal (Mes), Stem-A and Stem-B. Among them, Stem-A expresses genes relating to stemness and is correlated with poor clinical prognosis. In this study, we show that frizzled family receptor 7 (FZD7), a receptor for Wnt signalling, is overexpressed in the Stem-A subgroup. To elucidate the functional roles of FZD7, we used an RNA interference gene knockdown approach in three Stem-A cell lines: CH1, PA1 and OV-17R. Si-FZD7 OC cells showed reduced cell proliferation with an increase in the G0/G1 sub-population, with no effect on apoptosis. The cells also displayed a distinctive morphologic change by colony compaction to become more epithelial-like and polarised with smaller internuclear distances and increased z-axis height. Immunofluorescence (IF) staining patterns of pan-cadherin and β-catenin suggested an increase in cadherin-based cell–cell adhesion in si-FZD7 cells. We also observed a significant rearrangement in the actin cytoskeleton and an increase in tensile contractility in si-FZD7 OC cells, as evident by the loss of stress fibres and the redistribution of phospho-myosin light chain (pMLC) from the sites of cell–cell contacts to the periphery of cell colonies. Furthermore, there was reciprocal regulation of RhoA (Ras homolog family member A) and Rac1 (Ras-related C3 botulinum toxin substrate 1 (Rho family, small GTP-binding protein Rac1)) activities upon FZD7 knockdown, with a significant reduction in RhoA activity and a concomitant upregulation in Rac1 activity. These changes in pMLC and RhoA, as well as the increased TopFlash reporter activities in si-FZD7 cells, suggested involvement of the non-canonical Wnt/planar cell polarity (PCP) pathway. Selected PCP pathway genes (cadherin EGF LAG seven-pass G-type receptor 3 (CELSR3), prickle homolog 4 (Drosophila) (PRICKLE4), dishevelled-associated activator of morphogenesis 1 (DAAM1), profilin 2 (PFN2), protocadherin 9 (PCDH9), protocadherin α1 (PCDHA1), protocadherin β17 pseudogene (PCDHB17), protocadherin β3 (PCDHB3), sprouty homolog 1 (SPRY1) and protein tyrosine kinase 7 (PTK7)) were found to be more highly expressed in Stem-A than non Stem-A subgroup of OC. Taken together, our results suggest that FZD7 might drive aggressiveness in Stem-A OC by regulating cell proliferation, cell cycle progression, maintenance of the Mes phenotype and cell migration via casein kinase 1ɛ-mediated non-canonical Wnt/PCP pathway.

The Aerobic Capacity and Ventilatory Efficiency During Exercise in Qigong and Tai Chi Chuan Practitioners

The objective of this study was to compare cardiorespiratory responses to exercise among older Qigong participants, Tai Chi Chuan (TCC) practitioners and normal sedentary controls during cycle ergometry. Thirty-six community-dwelling men with a mean age of 59.1±6.6 years participated in this study. Each group (Qigong, TCC and control) included 12 subjects with matched age and body size. The Qigong group practiced Qigong regularly for 2.3±1.5 years; the TCC group practiced Yang TCC for 4.7±2.3 years. Heart rate (HR) responses were measured during the practice of Qigong and TCC. Additionally, breath-by-breath measurement of cardiorespiratory function was performed during the incremental exercise of leg cycling. The mean HR during Qigong and TCC practice was 91±5 bpm and 129±7 bpm, respectively. At the peak exercise and the ventilatory threshold (VeT), TCC group displayed highest oxygen uptake [Formula: see text], O2pulse and work rate among the three groups. The Qigong group also showed higher oxygen uptake and O2pulse than the control group. At the same relative exercise intensity, the Qigong group had the highest tidal volume among the three groups. In conclusion, Qigong and TCC show a beneficial effect to aerobic capacity in older individuals, but TCC displays a better training effect than Qigong due to its higher exercise intensity. However, Qigong can enhance breathing efficiency during exercise due to the training effect of diaphragmatic breathing.

Comparison of detection of glucose-6-phosphate dehydrogenase deficiency using fluorescent spot test, enzyme assay and molecular method for prediction of severe neonatal hyperbilirubinaemia

INTRODUCTION

This study aimed to compare the detection rates of glucose-6-phosphate dehydrogenase (G6PD) deficiency in neonates by fluorescent spot test (FST), enzyme assay and molecular methods, and to identify which method was a significant predictor of severe hyperbilirubinaemia.

METHODS

74 term infants of Chinese descent admitted with severe hyperbilirubinaemia (total serum bilirubin equal or greater than 300 micromol/L) and 125 healthy term infants born in the hospital without severe hyperbilirubinaemia were recruited into the study. Specimens of blood were collected from each infant for FST, G6PD enzyme assay and TaqMan minor groove binder single nucleotide polymorphism genotyping assay.

RESULTS

26 (13.1 percent) infants were diagnosed to have G6PD deficiency by FST. They had significantly lower median enzyme levels (0.8 IU/g Hb, interquartile range [IQR] 0.4-4.3) than those diagnosed to be normal (12.0 IU/g Hb, IQR 10.3-15.8) (p-value is less than 0.0001). Based on the enzyme assay, 39 (19.6 percent) infants had G6PD deficiency at an enzyme cut-off level of less than 8.5 IU/g Hb. G6PD mutation was detected in 27 (13.6 percent) infants. Logistic regression analysis showed that the only significant predictors of severe hyperbilirubinaemia were G6PD deficiency based on a cut-off level of less than 8.5 IU/g Hb (adjusted odds ratio [OR] 5.3, 95 percent confidence interval [CI] 2.4-11.4; p-value is less than 0.0001) and exclusive breast-feeding (adjusted OR 11.4, 95 percent CI 3.1-42.4; p-value is less than 0.0001). The gender and birth weight of infants, FST results, G6PD mutation and the actual G6PD enzyme levels were not significant predictors.

CONCLUSION

A G6PD enzyme level of less than 8.5 IU/g Hb is a significant predictor of severe hyperbilirubinaemia.

Tai Chi training for patients with coronary heart disease

Coronary heart disease (CHD) is the leading cause of death in the developed countries and many developing countries. Exercise training is the cornerstone of cardiac rehabilitation program for patients with CHD, and exercise intensities in the 50-70% heart rate reserve have been shown to improve functional capacity. However, recent studies found exercise with lower intensity also displayed benefits to CHD patients, and increased the acceptance of exercise program, particularly unfit and elderly patients. Tai Chi Chuan (TC) is a traditional conditioning exercise in the Chinese community, and recently it has become more popular in the Western societies. The exercise intensity of TC is low to moderate, depending on the training style, posture and duration. Participants can choose to perform a complete set of TC or selected movements according to their needs. Previous research substantiates that TC enhances aerobic capacity, muscular strength, endothelial function and psychological wellbeing. In addition, TC reduces some cardiovascular risk factors, such as hypertension and dyslipidemia. Recent studies have also proved that TC is safe and effective for patients with myocardial infarction, coronary bypass surgery and heart failure. Therefore, TC may be prescribed as an alternative exercise program for selected patients with cardiovascular diseases. In conclusion, TC has potential benefits for patients with CHD, and is appropriate for implementation in the community.

Subtrochanteric insufficiency fractures in patients on alendronate therapy: a caution

We carried out a retrospective review over ten months of patients who had presented with a low-energy subtrochanteric fracture. We identified 13 women of whom nine were on long-term alendronate therapy and four were not. The patients treated with alendronate were younger, with a mean age of 66.9 years (55 to 82) vs 80.3 years (64 to 92) and were more socially active. The fractures sustained by the patients in the alendronate group were mainly at the femoral metaphyseal-diaphyseal junction and many had occurred after minimal trauma. Five of these patients had prodromal pain in the affected hip in the months preceding the fall, and three demonstrated a stress reaction in the cortex in the contralateral femur. Our study suggests that prolonged suppression of bone remodelling with alendronate may be associated with a new form of insufficiency fracture of the femur. We believe that this finding is important and indicates the need for caution in the long-term use of alendronate in the treatment of osteoporosis.

Chronic intermittent hypoxia modulates eosinophil- and neutrophil-platelet aggregation and inflammatory cytokine secretion caused by strenuous exercise in men

Although acclimatization to intermittent hypoxia (IH) improves exercise performance by increasing oxygen delivery and utilization, the effects of chronic IH on platelet-leukocyte interaction and inflammation-related cytokine secretion caused by strenuous exercise remain unclear. This investigation elucidates how two intensities of IH influence eosinophil- and neutrophil-platelet aggregation (EPA and NPA) as well as pro- and anti-inflammatory cytokines mediated by strenuous exercise. Twenty healthy sedentary men were randomly divided into severe (SIH) and moderate (MIH) IH groups; groups were exposed to 12% O2 (SIH) and 15% O2 (MIH) for 1 h/day, respectively, for 5 days/wk for 8 wk in a normobaric hypoxia chamber. Before IH intervention, 1) exercise up to maximal oxygen consumption promoted shear stress-, LPS-, and N-formyl-methionyl-leucyl-phenylalanine-induced EPA, increased IL-1beta and malondialdehyde levels, and decreased total antioxidant levels in plasma and 2) exposure to 12% O2, but not to 15% O2 for 1 h, enhanced LPS-induced EPA and reduced plasma total antioxidant levels. After IH for 8 wk, hypoxia- and exercise-promoted EPA, IL-1beta, or malondialdehyde levels were suppressed in both MIH and SIH groups, and plasma IL-6 and IL-10 levels in the SIH group were increased. However, the NPA induced by the shear force and chemical agonists was not changed under the two IH regimens. Therefore, both MIH and SIH regimens ameliorate eosinophil- and platelet-related thrombosis, proinflammatory IL-1beta secretion, and lipid peroxidation enhanced by strenuous exercise. Furthermore, SIH simultaneously increases circulatory anti-inflammatory IL-6 and IL-10 concentrations. These findings can help to develop effective IH regimens that improve aerobic fitness and minimize risk of thromboinflammation.

Mortality, causes of death and associated risk factors in a cohort of diabetic patients after lower-extremity amputation: a 6.5-year follow-up study in Taiwan

BACKGROUND

To determine the mortality, causes of death and associated risk factors in Taiwanese diabetic patients after lower-extremity amputation (LEA).

METHODS

A total of 358 diabetic patients (191 men and 167 women, aged 66.6+/-10.3 years) after LEA from the Taiwanese cohort of 778 cases previously recruited in the multinational Global Lower Extremity Amputation Study were followed. Risk factors included age, sex, smoking, body mass index (BMI), hypertension, systolic (SBP) and diastolic blood pressure (DBP), and LEA level. Mortality was ascertained from the National Death Registry.

RESULTS

With a follow-up period of up to 6.5 (median: 4.0) years and 1239.17 patient-years, 214 patients died. Crude mortality rate was 172.7 per 1000 patient-years and median survival time 4.1 years. The underlying cause of death was recorded as diabetes mellitus in 57.9% of those who died and none to disease of arteries, arterioles and capillaries. After adjustment for age and sex, smoking, SBP as a continuous variable, SBP >or=140 mm Hg and BMI <18.5 kg/m(2) (underweight) were predictors for mortality with respective odds ratios (95% confidence intervals) of 1.580 (1.030-2.425), 1.011 (1.000-1.022), 1.363 (1.007-1.845) and 1.889 (1.203-2.968); but hypertension, DBP as a continuous variable and DBP >or=90 mm Hg, BMI as a continuous variable and LEA level were not.

CONCLUSIONS

Mortality after LEA in Taiwanese diabetic patients is high. The most common cause of death was recorded as diabetes mellitus. After adjustment for age and sex, smoking, SBP and underweight are predictive for mortality; while LEA level is not.

Effects of moderate and severe intermittent hypoxia on vascular endothelial function and haemodynamic control in sedentary men

Acclimatization to intermittent hypoxia (IH) improves exercise performance by enhancing oxygen delivery and utilization, but the effect of IH on hemodynamic control remains unclear. This study investigates how two intensities of IH influence hemodynamic control to develop an IH regimen that improves aerobic fitness and minimizes risk of peripheral vascular disorder. Thirty healthy sedentary men were randomly divided into severe (SIH) and moderate (MIH) IH and control (C) groups. The subjects were exposed to 12% (SIH), 15% (MIH), or 21% (C) O2 for 1 h/day, 5 days/week for 4 weeks in a normobaric hypoxia chamber. The results demonstrate that (1) improved pulmonary ventilation and oxygen uptake by SIH and MIH; (2) SIH elevated blood pressure during exercise and increased plasma malondialdehyde and nitric oxide (NO) metabolite levels, accompanied by reduced hyperaemic arterial response, venous compliance, endothelium-dependent vasodilatation, and decreased plasma total antioxidant and vitamin E levels; (3) while such effects were not seen following MIH; and (4) there were no significant differences in endothelium-independent vasodilatation during all experimental periods among the three groups. We conclude that both SIH and MIH regimens improve pulmonary ventilation. However, SIH but not MIH decreases anti-oxidative capacity and increases lipid peroxidation in circulation, leading to suppression of vascular endothelial function, causing impairment of vascular haemodynamics.

Recurrent pneumothorax in pregnancy: what should we do after placing an intercostal drain

Recurrent pneumothorax is rare during pregnancy. We describe a Chinese woman, with a history of spontaneous pneumothorax managed with an intercostal drain, who developed a recurrent pneumothorax during her 32nd week of pregnancy. There is no consensus on management in this situation. We review the literature and discuss different management approaches. Thirty-six cases of antepartum pneumothorax have been reported in 31 case reports. An intercostal drain only (n=11) or surgeries (thoracotomy, n=9; or video-assisted thoracoscopy, n=2) were common treatment options with no surgical complications reported. Twenty-two (61%) patients progressed to a normal vaginal delivery, while the rest required forceps delivery (22%) or Caesarean section (14%). No single treatment option outweighed the others. There were no maternal or foetal complications reported in those who underwent antepartum surgical intervention. Surgical management of recurrent pneumothorax during pregnancy is well tolerated.

The use of computer navigation in performing minimally invasive surgery for intertrochanteric hip fractures--The experience in Singapore

OBJECTIVE

Intertrochanteric hip fractures are very common and early mobilisation correlates with a better outcome. The ideal surgical procedure should protect the soft tissue envelope, thereby preserving blood supply and reducing blood loss. Furthermore, occupational exposure to fluoroscopy that is used in hip fracture fixation remains a concern amongst orthopaedic surgeons. Computer-aided surgery can help to reduce reliance on fluoroscopy. We therefore combined the principles of minimally invasive plate osteosynthesis (MIPO) and computer navigation to describe a new procedure. We also present our results using this technique of minimally invasive computer-navigated dynamic hip screw fixation (navMIS-DHS), and compare it to computer-navigated open DHS fixation (nav-DHS) and to conventional open DHS fixation (conv-DHS).

MATERIALS AND METHODS

This paper has three parts. In the first part, we describe the procedure of navMIS-DHS in detail. In the second part, we present our initial retrospective pilot series of 35 cases. Amongst them we performed 5 navMIS-DHS, 3 nav-DHS and 27 conv-DHS. There were also two cases of conv-DHS deliberately performed with a mini-incision in an attempt to see if we could duplicate the 5 cm incision that we achieved with navMIS-DHS. All patients were followed up for a minimum of 6 months. In the third part, we performed a single surgeon prospective evaluation of navMIS-DHS versus conv-DHS involving 43 fractures in two arms.

RESULTS

We were able to achieve reduction in fluoroscopy time. There was also reduction in opiate requirement post-operatively in the minimally invasive procedure. The incision sizes were also smaller. The prospective study also showed less wound-related complications in navMIS-DHS and a shorter time to ambulation. Implant positions were acceptable but we have also described how it may be improved.

CONCLUSIONS

Navigated MIS-DHS, by virtue of less pain, better healing, earlier rehabilitation and potentially shorter hospital stay, would benefit both the patients and reduce the economic strain on the health care system. It is a safe and reproducible procedure. Technical difficulties are present and these need to be addressed with further modifications of technique, and instrumentation.

Acute adverse reactions to magnetic resonance contrast media--gadolinium chelates

The objective of this study was to evaluate the clinical safety of intravenous gadolinium-based contrast media used in patients who underwent MRI at a single institution. Acute adverse reactions to intravenous gadolinium-based contrast media used for MRI at the Princess Margaret Hospital, Hong Kong, SAR, from January 1999 to November 2004 were recorded in an incidence log book. The medical records of patients' demographics were retrospectively reviewed and the nature, frequency and severity of the adverse reactions were investigated and documented. The incidence of acute adverse reactions to intravenous gadolinium-based contrast media was 0.48% (45 patients with 46 adverse reactions). The severity of these adverse reactions were 96% mild, 2% moderate (one patient developed shortness of breath that required oxygen supplementation and intravenous steroidal management) and 2% severe (one patient developed an anaphylactoid reaction, but successfully recovered through timely resuscitation). No patients were recorded as having contrast extravasation and none died as a result of any adverse reaction. Among the 45 patients who developed adverse reactions, three patients (6.7%) had prior adverse reactions to iodinated contrast media, three (6.7%) had prior reactions to a different gadolinium-based contrast agent, one (2%) had asthma and nine (20%) had a history of drug/food allergy. Overall, 41% of the adverse reactions were not documented in the final MRI report or the clinical medical records. Gadolinium-based contrast media are safe and well tolerated by the vast majority of patients. In our study, the adverse reaction rate (0.48%) and the incidence of severe anaphylactoid reaction (0.01%) concur with those reported in the literature. Although most of the symptoms are mild and transient, these adverse reactions must be accurately documented and managed.

Neuromuscular electric stimulation enhances endothelial vascular control and hemodynamic function in paretic upper extremities of patients with stroke

OBJECTIVE

To investigate the effects of neuromuscular electric stimulation (NMES) on endothelial vascular control and hemodynamic function in patients in rehabilitation after acute stroke.

DESIGN

Before-after trial.

SETTING

Inpatients in a tertiary hospital.

PARTICIPANTS

Sixteen stroke patients (11 women, 5 men) with a mean age of 60.6+/-19.5 years.

INTERVENTIONS

All patients received NMES for paretic wrist extensor and flexor muscles 30 minutes daily, 5 days a week, for 4 weeks. The nonparetic upper extremities, which served as controls, did not receive NMES.

MAIN OUTCOME MEASURES

Laser Doppler perfusion testing was conducted to measure cutaneous microcirculatory responses to transdermal iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP), as specific endothelium-dependent and -independent vasodilators, respectively. Arterial and venous hemodynamic function was also measured by impedance plethysmography.

RESULTS

Before NMES treatment, the venous capacity and compliance of the paretic extremities did not differ significantly from those of the nonparetic extremities. However, hyperemic arterial inflow, ACh-induced cutaneous perfusion, and the ratio of ACh- to SNP-induced cutaneous perfusion were lower in the paretic than in the nonparetic extremities. After NMES treatment, hyperemic arterial inflow and venous outflow increased by 21.5% and 57.2%, respectively, in the paretic extremities (P<.05). ACh-induced cutaneous perfusion and the ratio of ACh- to SNP-induced cutaneous perfusion were also significantly enhanced in the paretic extremities. In contrast, hyperemic arterial inflow decreased by 39.6% in the nonparetic extremities (P<.05), and endothelium-dependent cutaneous vasodilation also decreased significantly.

CONCLUSIONS

NMES therapy may enhance the hyperemic arterial response and endothelium-dependent dilation in skin vasculature in the paretic upper extremities of patients with stroke.

Lymphoepithelioma-like carcinoma of the lung: experience with ten cases

OBJECTIVE

Lymphoepithelioma-like carcinoma of the lung (LELC) is a rare form of non-small cell lung cancer predominantly affecting young non-smoking Asians, and there has been only limited experience in its palliative chemotherapy and radiotherapy. We investigated tumour response, time to progression and survival of LELC patients who received such treatment.

DESIGN

We prospectively recruited patients with confirmed advanced LELC who were treated with chemoradiotherapy in our unit, a regional tertiary referral centre for lung cancer treatment.

RESULTS

There were 10 patients (five males, age 47 +/- 9.8 years, median follow-up 22 months) with advanced LELC (respectively 1, 4, and 5 patients at TNM stage IIIA, IIIB and IV) who received systemic chemotherapy and radiotherapy. The primary chemotherapy regimen consisted of 5-fluorouracil/leucovorin/cisplatin. The response rates to 5-fluorouracil/leucovorin/cisplatin were 60% partial response, 10% stable disease, and 30% progressive disease. Eight patients were also given local radiotherapy. Five patients received salvage chemotherapy when disease progressed after primary chemotherapy. The overall median survival was 23.4 +/- 4.7 months.

CONCLUSION

The encouraging response to combination chemotherapy with 5-fluorouracil/leucovorin/ cisplatin, although empirical, supports its use with radiotherapy in unresectable lymphoepithelioma-like carcinoma of the lung.

Inhibition of tendon cell migration by dexamethasone is correlated with reduced alpha-smooth muscle actin gene expression: a potential mechanism of delayed tendon healing

Local corticosteroid injection is commonly used to treat sports-related tendon injuries. However, isolated cases of tendon rupture following injection suggest that this treatment may impair the healing process. Tendon healing requires the migration of tendon cells to the repair site, followed by the proliferation and synthesis of the extracellular matrix. This study was designed to determine the effect of dexamethasone on the migration of tendon cells intrinsic to rat Achilles tendon at concentrations similar to those typically used for local injection treatment. Furthermore, the existence of a correlation between this effect and the expression of the contractile actin isoform, alpha-smooth muscle (SM) actin, which is associated with cell motility, was also examined. Using cultured tendon cells, migration was evaluated by counting the number of initial outgrowths from the tendon explants and by transwell filter migration assay. The distribution and assembly of alpha-SM actin were assessed by immunocytochemistry. The mRNA and protein expressions of alpha-SM actin were determined by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. Dose-dependent dexamethasone inhibition was demonstrated for both tendon cells outgrowth from the explants, ex vivo, and migration of tendon cells through the transwell filter, in vitro. Immunocytochemical staining revealed significant decreases in both the amount and assembly of alpha-SM actin in cells. Suppression of mRNA expression and protein level of alpha-SM actin was revealed from RT-PCR and Western blot analyses. In conclusion, dexamethasone inhibits tendon cell migration that is correlated with decreased gene expression of alpha-SM actin.

Clinical analysis of 1048 children with developmental delay

BACKGROUND

Children with developmental delay (DD) have a variety of problems in developmental functions. The purposes of this study were to analyze the underlying diseases and risk factors in children with different functional delays.

METHODS

We collected data on 1048 children who underwent assessments of developmental function, related diseases, and risk factors. All children were classified into 6 functional delay groups: cognitive, speech, motor, pervasive, global, and non-specific DDs. Differences in related diseases and risk factors of the 6 functional delay groups were determined.

RESULTS

Most children had global (51.2%), speech (21.9%), and motor (13.9%) delays. Approximately 62.8% of children were associated with biological factors (19% with genetic defects or congenital anomalies, 16.5% with central nervous system lesions, 13.9% with prematurity/low birth body weight, and 13.4% with neonatal insult). We could not identify the risk factors in 36.6% of the children. Most children with motor delay had brain/neuromuscular diseases and were associated with risks of prematurity or low birth body weight; while most children with global delay had brain neuromuscular diseases or psychological/mental disorders and were associated with risks of genetic defects or congenital anomalies.

CONCLUSION

Our findings suggest that there are heterogeneous risk factors and related diseases in children with different kinds of functional delay.

Decreased expression of proliferating cell nuclear antigen is associated with dexamethasone inhibition of the proliferation of rat tendon fibroblasts

OBJECTIVE

To investigate the effects of dexamethasone (Dex) on the proliferation of cultured rat Achilles tendon fibroblasts at concentrations typically used for local injection treatment.

METHODS

Fibroblasts cultured from rat Achilles tendons were treated with Dex at concentrations of 0, 10-4, 3 10-4, and 10-3 M. [3H]thymidine incorporation was used to measure the rate of cell proliferation. mRNA expression of proliferating cell nuclear antigen (PCNA) and cyclin kinase inhibitor p21CIP1 was determined by reverse transcription-polymerase chain reaction (RT-PCR). The protein levels of PCNA and p21CIP1 were investigated by Western blot analysis.

RESULTS

An initial inhibitory effect on tendon fibroblast proliferation was observed at a concentration of 10-4 M. Further, a significant decline in [3H]thymidine incorporation as a function of Dex concentration was noted (p = 0.019). RT-PCR results revealed that PCNA mRNA expression was inhibited after Dex treatment. Western blot analysis of PCNA protein also revealed Dex downregulation. Gradual declines in the levels of PCNA mRNA expression and PCNA protein as a function of Dex concentration were noted. The expression of p21CIP1 both at mRNA and the protein levels remained constant.

CONCLUSION

These results suggest that Dex inhibition of the proliferation of rat tendon fibroblasts is associated with a p21CIP1 independent decrease of the PCNA gene expression.

Visual spatial attention in children with attention deficit hyperactivity disorder

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) was characterized by deficit in the attention mechanism. Until now, the visual-spatial attention deficit in children with ADHD remains controversial. We report a study of the visual spatial attention to assess covert shifts of attention and sustained attention theoretically linked to two neuroanatomically defined attentional system in the posterior and anterior parts of the human brain.

METHODS

Using the Neuroscan system, the reaction time (RT) was measured according to three different within-subject conditions including cueing (valid, invalid and neutral); delay (800 msec and 100 msec); side [right visual field (RVF) and left visual field (LVF)] as well as one between-subject condition (healthy, ADHD).

RESULTS

The AHDH group showed slower RTs overall (RT = 760 msec) than the comparison group (RT = 650 msec) (p = 0.001). RTs in the delayed condition of 800 msec (RT = 680 msec) were faster than in the delayed condition of 100 msec (RT = 730 msec) in all children (p < 0.001). The ADHD group showed significant lateral differences in RT (RTRVF: 880 msec > RTLVF: 830 msec) in the 100 msec delay for the invalid cueing condition (p = 0.045) that was not found in the comparison group.

CONCLUSION

General dysfunction including posterior-based covert shift of attention and anterior-based sustained attention was found in ADHD group. Furthermore, asymmetric left parietal dysfunction in the disengaged operation was noted in those with ADHD.

Heart rate responses and oxygen consumption during Tai Chi Chuan practice

Tai Chi Chuan (TCC) is a popular Chinese conditioning exercise, however, its exercise intensity remains controversial. The objective of this study was to determine the exercise intensity of Yang TCC by measuring heart rate (HR) responses and oxygen consumption (VO2) during practice. Fifteen men aged 39.9 +/- 9.5 yrs (range 26-56 yrs) participated in this study. Subjects had practiced classical Yang TCC for 5.8 +/- 2.4 years. HR responses and VO2 were measured during practice of TCC by using a K4 telemetry system. Blood lactate was measured before and immediately after TCC practice. Additionally, breath-by-breath measurement of cardiorespiratory function and sequential determination of blood lactate were performed during the incremental exercise of leg cycling. Measurements obtained during the TCC practice and exercise testing were compared to determine the exercise intensity of TCC. While performing TCC, the mean HR of subjects was 140 +/- 10 bpm, and the mean VO2 was 21.4 +/- 1.5 mL x kg(-1) min(-1). Compared with the data of the exercise test, the HR during practice was 58% of the heart rate range. Meanwhile, the VO2 during TCC practice was 55% of the VO2peak. Additionally, the level of blood lactate immediately after TCC practice was 3.8 mM, which reflected the level of lactate during TCC, approximated the onset of blood lactate accumulation (OBLA). The results demonstrate that TCC is an exercise with moderate intensity, and is aerobic in nature.

Suppressed cutaneous endothelial vascular control and hemodynamic changes in paretic extremities with edema in the extremities of patients with hemiplegia

OBJECTIVE

To investigate peripheral circulatory function and its underlying mechanisms in the paretic upper extremity after a stroke.

DESIGN

Case-control study.

SETTING

A department of physical medicine and rehabilitation in Taiwan.

PARTICIPANTS

A total of 53 hemiplegic patients (28 men, 25 women; mean age +/- standard deviation; 58.2+/-3.8y) were studied. Subjects were divided into edema and nonedema groups. The edema group included 29 hemiplegic patients with edematous paretic upper extremities. Twenty-four hemiplegic patients in the nonedema group did not suffer from limb edema in the paretic upper extremity.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Cutaneous microvascular perfusion responses to 3 grade levels of iontophoretically applied 1% acetylcholine (ACh), 1% ACh plus 1% N(G)-monomethyl-L-arginine (L-NMMA), and 1% sodium nitroprusside (SNP) in the skin of subjects' forearms were determined by laser Doppler perfusion measurements. Moreover, hemodynamic characteristics in the arterial and venous vessels were measured by impedance plethysmography.

RESULTS

Resting arterial inflow and venous capacity, tone, and outflow in paretic extremities did not significantly differ from nonparetic extremities, but the hyperemic arterial inflow was lower in paretic extremities than in nonparetic extremities, and paretic extremities were associated with lower ACh- and ACh plus L-NMMA-induced cutaneous perfusions than nonparetic extremities. ACh-induced cutaneous perfusions also decreased much more significantly in edematous paretic extremities than in nonedematous paretic extremities, and skin vascular responses to SNP do not differ significantly between paretic and nonparetic extremities.

CONCLUSION

Cutaneous microcirculatory function in the paretic upper extremity after stroke may be impaired. The impairment may occur because of decreased endothelium-dependent dilation in skin vasculature. Dysfunction in cutaneous microcirculation tends to be more pronounced in the edematous than in the nonedematous extremities.

Tai Chi Chuan training is associated with enhanced endothelium-dependent dilation in skin vasculature of healthy older men

OBJECTIVES

The vascular endothelium modulates vascular tone by synthesizing and metabolizing vasoactive substances. Endothelium-dependent vasodilation declines with age. This study investigated whether Tai Chi Chuan (TCC) training could enhance endothelial function in the skin vasculature of older men.

SETTING

Community setting.

DESIGN

Basic hemodynamic characteristics and skin vascular response to endothelium-dependent and -independent vasodilators were studied.

PARTICIPANTS

Ten older men who practiced TCC, 10 older healthy sedentary men, and 12 younger healthy sedentary men. The older TCC subjects had practiced classical Yang TCC for a mean +/- standard deviation of 11.2 +/- 3.4 years; mean attendance was 5.1 +/- 1.8 times weekly. Sedentary subjects had not participated in any regular exercise training for at least 5 years.

MEASUREMENTS

Different doses of 1% acetylcholine (ACh) and 1% sodium nitroprusside (SNP) were iontophoretically applied to the skin of subjects' lower legs, and cutaneous microvascular perfusion responses were determined by laser doppler measurements. Additionally, arterial and venous hemodynamic variables were measured by impedance plethysmograph.

RESULTS

The older TCC group had higher lower leg arterial blood flow (LABF); LABF in response to reactive hyperemia; and lower leg venous capacity, tone and blood flow than their sedentary counterparts, but the older TCC group displayed similar arterial and venous hemodynamic variables to the younger sedentary group. The younger sedentary group had a higher ACh-induced cutaneous perfusion and a higher ratio of ACh- to SNP-induced cutaneous perfusion than the two older groups. The older TCC group showed a higher ACh-induced cutaneous perfusion and a higher ratio of ACh- to SNP-induced cutaneous perfusion than the older sedentary group. Skin vascular responses to SNP did not differ significantly between the three groups.

CONCLUSIONS

Regular practice of TCC is associated with enhanced endothelium-dependent dilation in skin vasculature of older individuals. Moreover, TCC training may delay the age-related decline of venous compliance and hyperemic arterial response.