In vitro susceptibility of Alcaligenes denitrificans subsp. xylosoxidans to 24 antimicrobial agents.

The in vitro susceptibilities of 37 clinical isolates of Alcaligenes denitrificans subsp. xylosoxidans to 24 antimicrobial agents were determined. Imipenem was the only drug with consistent activity (MIC for 90% of isolates, 2 micrograms/ml). Piperacillin, ticarcillin-clavulanic acid, ceftazidime, and co-trimoxazole were active against most strains. All the isolates were resistant to ampicillin, cefazolin, cefuroxime, cefamandole, cefotetan, ceftriaxone, cefotaxime, aztreonam, amdinocillin, and temocillin. Most isolates were resistant to the aminoglycosides tested, including amikacin. Lack of activity was also observed for all new 4-quinolone antimicrobial agents.     

One systemic administration of transforming growth factor-beta 1 reverses age- or glucocorticoid-impaired wound healing.

The role of intravenously administered recombinant human transforming growth factor-beta 1 (rhTGF-beta 1) on the healing of incisional wounds in rats with impaired healing due to age or glucocorticoid administration was investigated. The administration of methylprednisolone to young adult rats decreased wound breaking strength to 50% of normal control. Breaking strength of incisional wounds from 19-mo-old rats was decreased approximately 27% compared with wounds from normal healing young adult rats. A single intravenous administration of rhTGF-beta 1 (100 or 500 micrograms/kg) increased wound breaking strength from old rats or young adult rats with glucocorticoid-induced impaired healing to levels similar to normal healing control animals when determined 7 d after injury. Even though the circulating half-life of systemically administered rhTGF-beta 1 is < 5 min, a sustained stimulatory effect on extracellular matrix secretion was evident in glucocorticoid-impaired rats when rhTGF-beta 1 was administered at the time of wounding, 4 h after wounding, or even 24 h before wounding. These observations indicate a previously unrecognized potential for the active form of TGF-beta 1 to profoundly influence the wound healing cascade after brief systemic exposure.     

Vascular calcification is associated with impaired microcirculatory function in chronic haemodialysis patients

Although vascular calcification (VC) in dialysis patients is associated with increased cardiovascular events, the pathophysiology is still largely obscure. Microcirculatory dysfunction may contribute to demand myocardial ischaemia. We have studied cutaneous microcirculatory function in haemodialysis (HD) patients with and without large-vessel VC. 37 non-diabetic subjects (20 HD and 17 healthy controls) were studied. VC was assessed using CT scanning of a standardised segment of superficial femoral artery (11 VC+, 9 VC-). Laser Doppler imaging was undertaken using a Periscan PIM II(R) at rest and under vasodilator challenge. Baseline perfusion was not statistically different in VC+ patients than VC- patients or controls (1.03 +/- 0.2, 1.08 +/- 0.2, 0.93 +/- 0.3 PU respectively). Overall, the maximum vasodilatory response to both ACh (p < 0.001) and SNP (p = 0.004) was lower in the HD than the control group. In addition, the HD patients took longer to reach a maximum vasodilatation than the controls (p = 0.008 for ACh, n.s. for SNP). Further, the maximum vasodilatory response in the VC+ patients was lower and patients took longer to reach maximum vasodilatation than the VC- group. We have demonstrated, for the first time, impaired and dysregulated microcirculatory function in patients with VC. This may be important in understanding the pathophysiology of the complications and cardiovascular consequences of VC.     

Doppler ultrasound in noninvasive cardiac evaluation. The growing range of applications

Ultrasound is of proven clinical utility for imaging cardiac structures. Doppler ultrasonic techniques can be used with or without echocardiography for noninvasive hemodynamic studies. The usefulness of Doppler ultrasonic techniques in the noninvasive laboratory has been shown recently at the Massachusetts General Hospital, Boston. In 61 of 100 consecutive patients in a prospective study, Doppler ultrasound provided clinical information that could not be obtained with echocardiographic studies alone. The advantages of this technique for noninvasive cardiac studies are now being recognized in the general medical community. The results of ongoing clinical investigations will help define the role of Doppler echocardiography as a clinically useful diagnostic tool for cardiac evaluation.     

The effect of patella resurfacing in total knee arthroplasty on functional range of movement measured by flexible electrogoniometry

BACKGROUND: The need for patella resurfacing remains an area of considerable controversy in total knee replacement surgery. There would appear to be no reported evidence on the effect of patella resurfacing on knee function, as measured by functional range of movement used in a series of tasks, in patients undergoing knee replacement. The object of this study was to measure knee joint motion during functional activities both prior to and following total knee replacement in a randomised group of patients with and without patella resurfacing and to compare these patient groups with a group of normal age-matched subjects. METHODS: The study design was a double blinded, randomised, prospective, controlled trial. The knee joint functional ranges of movement of a group of patients (n=50, mean age=70 years) with knee osteoarthritis were investigated prior to and following total knee arthroplasty (4 months and 18-24 months) along with a group of normal subjects (n=20, mean age=67). Patients were randomly allocated into two groups, those who received patella resurfacing (n=25) and those who did not (n=25). Flexible electrogoniometry was used to measure the flexion-extension angle of the knees with respect to time in eleven functional activities. FINDINGS: No statistically significant differences (alpha level 0.05) in joint excursion of the affected knee were found between patients who received patella resurfacing and those who did not. INTERPRETATION: Routine patella resurfacing in a typical knee arthroplasty population does not result in an increase in the functional range of movement used after knee replacement.     

Functional MRI with active, fully implanted, deep brain stimulation systems: safety and experimental confounds

We investigated safety issues and potential experimental confounds when performing functional magnetic resonance imaging (fMRI) investigations in human subjects with fully implanted, active, deep brain stimulation (DBS) systems. Measurements of temperature and induced voltage were performed in an in vitro arrangement simulating bilateral DBS during magnetic resonance imaging (MRI) using head transmit coils in both 1.5 and 3.0 T MRI systems. For MRI sequences typical of an fMRI study with coil-averaged specific absorption rates (SARs) less than 0.4 W/kg, no MRI-induced temperature change greater than the measurement sensitivity (0.1 degrees C) was detected at 1.5 T, and at 3 T temperature elevations were less than 0.5 degrees C, i.e. within safe limits. For the purposes of demonstration, MRI pulse sequences with SARs of 1.45 W/kg and 2.34 W/kg (at 1.5 T and 3 T, respectively) were prescribed and elicited temperature increases (>1 degrees C) greater than those considered safe for human subjects. Temperature increases were independent of the presence or absence of active stimulator pulsing. At both field strengths during echo planar MRI, the perturbations of DBS equipment performance were sufficiently slight, and temperature increases sufficiently low to suggest that thermal or electromagnetically mediated experimental confounds to fMRI with DBS are unlikely. We conclude that fMRI studies performed in subjects with subcutaneously implanted DBS units can be both safe and free from DBS-specific experimental confounds. Furthermore, fMRI in subjects with fully implanted rather than externalized DBS stimulator units may offer a significant safety advantage. Further studies are required to determine the safety of MRI with DBS for other MRI systems, transmit coil configurations and DBS arrangements.     

Validation of the Brief Pain Inventory in a Taiwanese population

Assessment of pain in cancer patients is very important to all health care professionals. This paper describes the development of a Taiwanese version of the Brief Pain Inventory (BPI-T) and discusses its psychometric properties in Taiwan. The BPI-T was developed from the original BPI using back-translation and committee review. A total of 534 cytologically or pathologically diagnosed cancer patients in three medical centers in Taiwan were interviewed between July 1992 and October 1997. The intraclass correlation coefficient for the test-retest reliability was 0.79 for the pain severity scale and 0.81 for the pain interference scale. The explained variance for the within-scale factor analyses was larger than 60% in both scales. The coefficient alpha for the internal reliability was 0.81 for the severity scale and 0.89 for the interference scale. Confirmatory factor analysis of the BPI-T clearly identified the same two scales (severity and interference scales) in the 299 adult patients (age between 20-64) with high education (education years > 9) or patients at an early stage of disease. However, in the 235 nonadult patients with distant metastasis or low education patients with distant metastasis, the "most severe pain" item loaded more to the interference scale than the severity scale. Convergent validity of the pain severity was demonstrated by significant correlations with stage of disease (National Cancer Institute's Surveillance, Epidemiology, and End Results Program [SEER]), performance status (Eastern Cooperative Oncology Group [ECOG]), and pain interference. In conclusion, interviewer-administered BPI-T was a reliable instrument for cancer pain severity and its interference in Taiwan. Additionally, it was a valid instrument on adult cancer patients with high education or patients at an early stage of disease.