Fast whole-body assessment of metastatic disease using a novel magnetic resonance imaging system: initial experiences

OBJECTIVE: The objective of this study was to investigate the clinical use of a novel whole-body magnetic resonance imaging (MRI) system for comprehensive assessment of tumor spread in clinical routine. MATERIAL AND METHODS: Sixty-five patients with different tumors with known metastatic disease and 6 healthy volunteers were included. High-resolution MRI from head to toe was performed using multiple phased-array surface coil elements, 24 independent receiver channels, and an integrated parallel acquisition technique (iPAT). A total room time of less than 60 minutes was required. Whole-body MRI and conventional spiral computed tomography (CT) were independently evaluated and compared in terms of feasibility, location/number of detected metastases, and therapeutic relevance. RESULTS: Whole-body MRI was successfully performed in 68 of 71 subjects. Compared with CT, more metastases were detected by MRI in 11 of 63 patients (17%), particularly in brain, liver, spleen, lymph nodes, bone marrow, muscle, and subcutaneous fat tissue. According to these findings, therapy had to be modified in 6 of 63 patients (10%). CONCLUSIONS: High-resolution whole-body MRI is feasible in clinical routine within 1 single examination and offers great potential for fast assessment of individual tumor spread and total tumor burden.     

First report of a vincristine dose-related Raynaud's phenomenon in an adolescent with malignant brain tumor

The authors report a case of a vincristine-induced, reproducible dose-related Raynaud's phenomenon. It occurred in a 14-year-old boy with a malignant brain tumor who received repeated vincristine injections. The authors describe how they handled this severe secondary Raynaud's phenomenon with acral cutaneous tissue necrosis. Reducing the dose of the vinca-alkaloid injections, together with an additional medication with a calcium-channel blocking agent, was a successful strategy in this patient. There are few case reports of secondary Raynaud's phenomenon in adult oncologic patients receiving certain anticancer drugs (including vincristine, bleomycin, and cisplatin), and to the authors' knowledge this kind of vincristine toxicity has not previously been described in either adults or children.     

The detection of Brucella spp. using PCR-ELISA and real-time PCR assays

Brucellosis is a worldwide 're-emerging' zoonosis causing high economic losses and severe human disease. Consequently, rapid and reliable, sensitive and specific, easy to perform and automated detection systems for Brucella spp. are urgently needed to allow early diagnosis and adequate antibiotic therapy in time. Real-time PCR assays using hybridization probes meet all these requirements. In 2003 various assays have been developed and evaluated for use in human and animal brucellosis. Genus-specific real-time PCR assays e.g. based on the bcsp31 gene will lead to an early diagnosis but for the purpose of epidemiological surveillance a species-specific real-time PCR deriving from the conventional AMOS (AbortusMelitensisOvisSuis)-PCR is necessary. Advantages and disadvantages of the different methods for real-time detection of Brucella spp. and a newly developed PCR-ELISA system for the high throughput of clinical samples will be discussed.     

Application of Bispectral Index and Narcotrend index to the measurement of the electroencephalographic effects of isoflurane with and without burst suppression

BACKGROUND: The Narcotrend monitor (MonitorTechnik, Bad Bramstedt, Germany) has recently been introduced as an intraoperative monitor of anesthetic state, based on a classification scheme originally developed for visual assessment of the electroencephalogram. The authors compared the performance of the Narcotrend index (software version 4.0) to the Bispectral Index (BIS, version XP; Aspect Medical Systems, Natick, MA) as electroencephalographic measures of isoflurane drug effect during general anesthesia. METHODS: The authors observed 15 adult patients scheduled to undergo radical prostatectomy with a combined epidural-isoflurane general anesthesia technique. At least 45 min after induction of general anesthesia, during a phase of constant surgical stimulation, end-tidal isoflurane concentrations were varied between 0.5 and 2.0 multiples of minimum alveolar concentration, and the BIS and the Narcotrend index were recorded. The prediction probability (PK) was calculated for the BIS and the Narcotrend index to predict isoflurane effect compartment concentration for each measure. The correlation analysis of the BIS and the Narcotrend index with the isoflurane effect compartment concentration was obtained by pharmacodynamic modeling based on two sigmoidal curves to account for the discontinuity in both indices with the onset of burst suppression. RESULTS: The prediction probabilities were indistinguishable (BIS PK = 0.72 +/- 0.07 (mean +/- SD); range, 0.61-0.84; Narcotrend index PK = 0.72 +/- 0.10; range, 0.51-0.87), as were the correlations between the electroencephalographic measures and isoflurane effect compartment concentrations (BIS R = 0.82 +/- 0.12; Narcotrend index R = 0.85 +/- 0.09). The pharmacodynamic models for the BIS and the Narcotrend index yielded nearly identical results. CONCLUSIONS: The BIS and the Narcotrend index detected the electroencephalographic effects of isoflurane equally. Combining two fractional sigmoid Emax models adequately described the data before and after the onset of burst suppression.     

Modulation of Xenopus laevis Ca-activated Cl currents by protein kinase C and protein phosphatases: implications for studies of anesthetic mechanisms

Ca-activated Cl currents (I(Cl(Ca))) are used frequently as reporters in functional studies of anesthetic effects on G protein-coupled receptors using Xenopus laevis oocytes. However, because anesthetics affect protein kinase C (PKC), they could indirectly affect I(Cl(Ca)) if this current is regulated by phosphorylation. We therefore studied the effect of modulation of either PKC or protein phosphatases PP1alpha and PP2A on I(Cl(Ca)) stimulated either by lysophosphatidate (LPA) signaling or by microinjection of Ca. X. laevis oocytes were studied under voltage clamp. Rat PP1alpha and PP2A were overexpressed in oocytes. PP, inositoltrisphosphate (IP(3)), the PP inhibitor okadaic acid (OA), the PKC inhibitor chelerythrine, or CaCl(2) were directly injected into the oocyte. Responses to agonists (LPA 10(-6) M, IP(3) 10(-4) M, CaCl(2) 0.5 M) were measured at a holding potential of -70 mV in the presence or absence of the PP inhibitors cantharidin or OA. PP1 alpha and PP2A inhibited I(Cl(Ca)) from 7.6 +/- 0.9 microC to 2.5 +/- 0.9 microC and 3.2 +/- 1.4 microC, respectively. PP inhibition enhanced I(Cl(Ca)) in control oocytes and reversed the inhibitory effect in oocytes expressing PP1 alpha or PP2A. PKC inhibition by chelerythrine enhanced both LPA- and CaCl(2)-induced I(Cl(Ca)). Our data indicate that the Xenopus I(Cl(Ca)) is modulated by phosphorylation. This may complicate design and interpretation of studies of G protein-coupled receptors using this model.     

Impact of bispectral index monitoring on stress response and propofol consumption in patients undergoing coronary artery bypass surgery

BACKGROUND: Bispectral Index (BIS)-titrated administration allows a reduction of propofol infusion rates in patients undergoing surgery. Resulting differences in anesthetic depth might affect the stress response to surgery involving neural circuitry not reflected in the electroencephalogram. METHODS: Forty patients scheduled to undergo elective coronary artery bypass grafting receiving a background infusion of remifentanil (0.3 microg . kg . min) were anesthetized with intravenous propofol delivered by target-controlled infusion according to the Marsh pharmacokinetic model under BIS monitoring. In a randomized, prospective design, 20 patients received propofol at a target concentration of 3 microg/ml, whereas in 20 patients propofol was titrated to maintain a BIS value of 40-50. Plasma concentrations of propofol (by means of gas chromatography-mass spectrometry), epinephrine, norepinephrine (by means of high-pressure liquid chromatography), cortisol (by means of radioimmunoassay), and interleukins 6 and 10 (by means of enzyme-linked immunosorbent assay) were measured repeatedly throughout surgery. RESULTS: BIS monitoring allowed a 30% reduction of propofol infusion rates and a similar decrease in plasma propofol concentrations in the BIS group without affecting the stress response to surgery for the group mean. None of the patients reported awareness during a standardized interview. Interestingly, propofol-remifentanil anesthesia blunted the release of epinephrine and cortisol to bypass surgery completely even when the propofol infusion rate was reduced according to BIS values. CONCLUSIONS: Total intravenous anesthesia using propofol-remifentanil effectively attenuates the neurohumoral stress response to coronary bypass surgery involving cardiopulmonary bypass. Titration of propofol using BIS allows for significant reduction of propofol consumption, with only minor effects on stress response under these conditions.     

Is surgery necessary for asymptomatic tethered cord in anorectal malformation patients?

Background

Evidence supporting routine surgery for asymptomatic tethered cord in patients with anorectal malformation (ARM) is, at best, speculative. The authors therefore examined whether untethering is indicated for asymptomatic tethered cord in patients with ARM.

Methods

A retrospective analysis of all patients with ARM (n = 223) between 1992 and 2002 was conducted. During the same period, 435 patients had surgery for tethered cord.

Results

Tethered cord was detected radiologically in 22 (9.8%); 8 patients with a low conus, and 14 with a low conus with and thickened filum. Seven of 22 patients underwent untethering; 3 prophylatic (14%) and 4 for neuro/motor function deficits (18%). All 4 symptomatic patients had significant clinical improvement in their neuro/motor functions after surgery. However, bowel and urinary functions remained unchanged in all 7 patients with a mean follow-up of 6.4 years (range, 4 to 8 years). Fifteen patients with radiologically diagnosed tethered cord remain asymptomatic with a mean follow-up of 2.7 years (range, 8 months to 10 years).

Conclusions

Neuro/motor functions clearly improved with surgery in symptomatic patients. However, bowel and urinary functions remained unchanged after surgery. Only 4 ARM patients with tethered cord required surgery, whereas prophylactic surgery appears to have minimal benefit. Expectant conservative approach in the management of asymptomatic tethered cord patient appears to be safe.     

Transurethral holmium laser enucleation of the prostate compared with transvesical open prostatectomy: 18-month follow-up of a randomized trial

PURPOSE: This ongoing randomized study aims to find out whether transurethral holmium laser enucleation of the prostate (HoLEP) could be an alternative to open transvesical prostatectomy in patients with prostates >100 g. PATIENTS AND METHODS: A series of 120 urodynamically obstructed patients were randomized to HoLEP or open prostatectomy, 60 patients to each group. The HoLEP was performed with high-powered Ho:YAG lasers at 80 to 100 W (2.0 J, 40-50 Hz) and 550-nm bare laser fibers. The American Urological Association Symptom Scores, peak urinary flow rates, and postvoiding residual urine volumes were evaluated preoperatively and at 1, 3, 6, 12, and 18 months postoperatively. All complications were noted. RESULTS: By the Mann-Whitney test, there was no significant difference between the HoLEP and open surgery groups in patient age (69.0 years HoLEP v 71.0 years open surgery), prostate volume (115 cc [range 100-230 cc] v 113 cc [100-230 cc], or weight of resected tissue (94 g [range 57-220 g] v 96 g [range 61-220 g]). There were significant differences in the mean operative time (136 v 91 minutes; P< 0.0001), mean hemoglobin loss (1.9 v 2.8 g/dL; P< 0.0001), median catheter time (1 day v 6 days; P< 0.0001), and median hospital stay (2 days v 10 days; P< 0.0001). Both HoLEP and open prostatectomy resulted in pronounced and lasting postoperative improvements in Symptom Scores, peak urinary flow rates, and postvoiding residual volumes (P< 0.0001). The differences between HoLEP and open prostatectomy were not significant at any interval for any parameter. Blood transfusions were required in 0 HoLEP patients v 8 open surgery patients. Arterial bleeding occurred in three patients in each group. Secondary apical resection was required in two HoLEP patients and no open surgery patients. Bladder neck contracture occurred in none of the HoLEP patients and two of those having open surgery. Thus, the total number of patients having complications was 7 with HoLEP and 13 with open surgery. There were no deaths in either group. CONCLUSIONS: The HoLEP appears to be an endourologic alternative to open surgical enucleation of the prostate for large glands. It entails significantly less blood loss and a much shorter catheter time and hospital stay. The perioperative outcome strongly favors the holmium procedure. The rate of late complications is equally low with each procedure. The postoperative micturition improvement was significant and lasting and was equivalent in the two groups.     

Ultrasound-induced microbubble coalescence

We studied the interaction of ultrasound contrast agent bubbles coated with a layer of lipids, driven by 0.5 MHz ultrasound. High-speed photography on the submicrosecond timescale reveals that some bubbles bounce off each other, while others show very fast coalescence during bubble expansion. This fast coalescence cannot be explained by dissipation-limited film drainage rates. We conclude that the lipid shell ruptures upon expansion, exposing clean free bubble interfaces that support plug flow profiles in the film and inertia-limited drainage whose time scales match those of the observed coalescence.     

Insulin resistance in patients with polycystic ovary syndrome

With a prevalence of 5%-10% the polycystic ovary syndrome (PCOS) is an exceptionally common disorder of premenopausal women. According to prospective studies, women with PCOS present abnormal glucose tolerance and diabetes mellitus in 31%-35% and 7.5%-10%, respectively. PCOS patients have a higher prevalence of cardiovascular risk factors such as hypertension, type 2 diabetes and dyslipidaemia. The rate of spontaneous abortions as well as the risk to develop gestational or type 2 diabetes is increased in PCOS. Therefore, PCOS is not only a reproductive problem but a complex endocrine disease with important health implications. The role of the glucose metabolism in PCOS, the health consequences and possible interventions are reviewed in this article.