Assessment of the deformation of the Bateman bipolar hip prosthesis inner bearing due to moisture absorption and creep.

The mechanism of inner bearing stiffness of bipolar hip prostheses has been investigated. The Ultra-high Molecular Weight Polyethylene (UHMWPE) component of the Bateman bipolar hip prosthesis has been subjected to a series of static and dynamic tests to assess water absorption and creep. Although deformation of the UHMWPE occurred, this did not produce an increased resistance to movement in the inner bearing.     

Performance of sodium iodide based (18)F-fluorodeoxyglucose positron emission tomography in the characterization of indeterminate pulmonary nodules or masses

The purpose of this study was to document the accuracy of (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) with sodium iodide detectors in characterizing indeterminate lung nodules or masses and in identifying additional extra-lesional findings. 50 consecutive patients without a confident diagnosis of malignancy on CT underwent (18)FDG PET with and without attenuation correction. The diagnosis of malignancy was made using visual diagnostic criteria, and tumour-to-blood pool ratios were calculated. The final diagnosis was established by surgery, biopsy or long-term follow-up. Any additional findings made at PET were recorded and similarly verified. Using blinded visual diagnostic criteria for the differentiation of malignant from benign nodules, sodium iodide PET achieved a sensitivity of 91% (30 of 33 cases), a specificity of 88% (15 of 17 cases), a positive predictive value for malignancy of 94% (30 of 32 cases) and a negative predictive value of 83% (15 of 18 cases). False positives occurred with active tuberculosis and sarcoidosis. False negatives were a 3 cm bronchoalveolar carcinoma, a 1.3 cm sarcoma metastasis and a 1 cm carcinoma. Use of tumour-to-blood pool ratios did not improve performance. PET suggested the presence of nodal or distant metastases in 13 of 33 patients with a malignant pulmonary lesion. These PET findings were confirmed in 11 patients. These results indicate that sodium iodide PET is an accurate tool for the characterization of indeterminate pulmonary masses or nodules and simultaneously provides non-invasive staging information that can alter patient management in up to one-third of such patients. Performance of sodium iodide PET is comparable with reported results for PET scanners using other detector materials.     

Isolation of intestinal spirochaetes from homosexuals

Spirochaetes were isolated from rectal swabs of two homosexuals and the faeces of a third, using simple isolation techniques not previously applied to specimens of this type. The ease of culture of these organisms will enable their distribution and pathogenicity to be studied, particularly in relation to their significance in homosexuals.     

The effect of changing practice on fall prevention in a rehabilitative hospital: the Hospital Injury Prevention Study

OBJECTIVES: To determine whether a change in practice to introduce a multidisciplinary fall-prevention program can reduce falls and injury in nonacute patients in a rehabilitation hospital. DESIGN: A quasi-experimental study. SETTING: Three geriatric wards with a similar design, equipment, staffing levels, and skill mix. PARTICIPANTS: Eight hundred twenty-five consecutive patients. INTERVENTION: The patients' fall-risk status was assessed using the Downton Score. Current practice was maintained on the two control wards (n=550). On the experimental ward (n=275), a fall-prevention program was introduced. A multidisciplinary team met weekly specifically to discuss patients' fall risk and formulate a targeted plan. Patients at risk were identified using wristbands; risk factors were corrected or environmental changes made to enhance safety. MEASUREMENTS: Primary outcomes were number of fallers, recurrent fallers, total falls, patients sustaining injury, and falls per occupied bed days. Secondary outcomes were place of discharge and mortality. RESULTS: Patients were matched for age and risk status. Control wards had proportionally more fallers (20.2% vs 14.2%: P=.033), patients sustaining injury (8.2% vs 4%: P=.025), and total number of falls (170 vs 72: P=.045). These results did not remain significant after controlling for differing length of stay. There was no reduction in recurrent fallers (6.4% vs 4.7%: P=.43) and no effect on place of discharge (home discharges; 57.5% vs 60.7%: P=.41) or mortality (15.3% vs 13.8%: P=.60). CONCLUSION: This study shows that falls might be reduced in a multidisciplinary fall-prevention program, but the results are not definitive because of the borderline significance achieved and the variable length of stay. More research on fall prevention in hospital is required, particularly as to what interventions, if any, are effective at reducing falls in this group of patients.     

Behavioral disturbances, not cognitive deterioration, are associated with altered food selection in seniors with Alzheimer's disease

OBJECTIVE: We previously reported alterations in circadian patterns of food intake that are associated with measures of functional and cognitive deterioration in seniors with probable Alzheimer's disease (AD). This study further explored disturbed eating patterns in AD, focusing on alterations in macronutrient (protein, carbohydrate, and fat) selection, and their association with measures of functional and behavioral losses. METHODS: Forty-nine days of food intake collections were conducted on 32 residents (26 females, 6 males; age = 88.4 +/- 4.1 years; body mass index = 24.1 +/- 4.0 kg/m(2)) with probable AD residing at a nursing home (a fully accredited geriatric teaching facility affiliated with the University of Toronto's Medical School). All residents ate their meals independently. The relationships between patterns of habitual food consumption and measures of cognitive function (Severe Impairment Battery), behavioral disturbances (Neuropsychiatric Inventory-Nursing Home Version) and behavioral function (London Psychogeriatric Rating Scale) were examined, cross-sectionally. RESULTS: Consistent with our previous studies, breakfast intakes were not predicted by any of the measures of behavioral, cognitive, or functional deterioration, although those residents with greater functional deterioration, especially disengagement, attained lower 24-hour energy intakes. The presence of "psychomotor disturbances," including irritability, agitation, and disinhibition, were strongly associated with shifts in eating patterns toward carbohydrate and away from protein, placing individuals with these conditions at increased risk for inadequate protein intakes. Between-individual differences in intake patterns could not be explained by the use of either anorexic or orexigenic medications. CONCLUSIONS: Behavioral, not cognitive, deterioration is associated with appetite modifications that increase risk of poor protein intake, perhaps indicating a common monoaminergic involvement.     

心房颤动的电生理重构

心房颤动 (atrial fibrillation,AF)是临床上最常见的一种持续性心律失常 ,其发病率随年龄而增加 ,40岁以下人群发病率约为 0 .2 %～ 0 .3% ,6 0～ 90岁年龄组发病率增至5 %～ 9% [1 ] 。新近 Framingham的研究表明 AF可以成为一种独立的因素使患者病死率增加 [2 ] 。 AF的发病机制尚未完全清楚 ,可能为非单一机制 ,普遍认为持续性 AF是由于心房内的多子波折返 ,每 1个折返环本身都在不停地改变其大小及传导方向。近年来 ,在 AF的基础及临床研究中 ,两个方面的进展具有十分重要的意义 :一是发现部分 AF起源于心房内某些部位如肺静脉口…     

Subcutaneous fluid infusion in a long-term care setting

OBJECTIVE: To study the use of hypodermoclysis in a long-term care setting for chronic fluid supplementation and to compare it to intravenous (IV) fluid in the treatment of acute mild to moderate dehydration. DESIGN: A prospective observational study. PARTICIPANTS: Fifty-five residents of a long-term care facility treated with fluid therapy during a 5-week period. MAIN OUTCOME MEASURES: Efficacy of hydration and adverse effects were obtained from detailed chart review, interviews with healthcare providers, and investigators' observations. RESULTS: The study subjects were frail older people. Hypodermoclysis was used for maintenance fluid needs in 24 residents; none of these residents required any additional fluid therapy for dehydration. In addition, 37 residents received fluids for acute dehydration. In these residents, hypodermoclysis was associated with clinical improvement in 57% and no clinical change in 25%. Recipients of IV fluids improved 81% of the time and the remainder were unchanged. Hypodermoclysis was associated with fewer fluid therapy-related complications relative to IV therapy (P = .04). CONCLUSIONS: Hypodermoclysis is an effective procedure for providing fluids for both chronic maintenance needs and acute situations associated with mild to moderate dehydration in a long-term care setting. Hypodermoclysis appears safer and can avoid transfers to hospital for rehydration.     

Full-length but not truncated CD34 inhibits hematopoietic cell differentiation of M1 cells

CD34 is expressed on human and murine hematopoietic stem and progenitor cells and its clinical usefulness for isolation of stem/progenitor cells has been well established. Although expression of CD34 is regulated in a developmental stage-specific manner, the function of CD34 is not known. Recently we have shown that both a full-length and truncated form of CD34 protein is expressed by hematopoietic cells (Blood 84:691, 1994). To test whether failure to suppress either form of CD34 could affect terminal myeloid differentiation, we constitutively expressed these CD34 proteins in murine M1 myeloid leukemia cells, which can be terminally differentiated to macrophages by treatment with interleukin-6 of leukemia inhibitory factor. Surprisingly our results show that forced expression of the full-length but not the truncated form of CD34 impedes terminal differentiation by these agents. Because the difference between the two forms of CD34 protein resides in the length of their respective cytoplasmic tail domains, our findings strongly suggest that the cytoplasmic domain region of full-length CD34 is responsible for the observed maturation arrest phenotype. These findings suggest a potential negative regulatory role for full-length CD34 in hematopoietic cell differentiation and may explain, at least in part, the block in maturation observed in CD34+ acute myeloid leukemia.     

Bone marrow transplantation for patients with Philadelphia chromosome- positive acute lymphoblastic leukemia

We report the treatment outcome of allogeneic bone marrow transplantation in ten patients with Philadelphia chromosome-positive acute lymphoblastic leukemia. Six patients are alive and well for 6 to 30 months (median 19 months) after transplantation. Four patients died with transplant related complications. In view of the poor prognosis associated with this disease, marrow ablation followed by allogeneic or syngeneic marrow grafting may be the preferred treatment modality if a suitable marrow donor is available.