Portable spectral Doppler echocardiographic device: overcoming limitations

BACKGROUND

There is evidence that new portable echocardiographic devices are useful in evaluating heart anatomy and function, but a lack of Doppler modes has up to now been an important limitation in obtaining haemodynamic data.

OBJECTIVES

To report the Doppler capabilities of a new hand held echocardiographic device.

DESIGN

Blinded comparison of two types of echocardiography machine.

SETTING

Tertiary care centre.

PATIENTS

98 consecutive patients were randomly imaged with the hand held device, with a standard platform as reference.

OUTCOME MEASURES

Pulsed wave transmitral Doppler inflow tract velocities, deceleration time, and continuous wave Doppler measurements of aortic ejection and tricuspid regurgitation peak velocities were recorded.

RESULTS

There was excellent agreement between the hand held device and standard echocardiography for the evaluation of diastolic E and A waves, E/A ratio, and deceleration time with pulsed wave Doppler (intraclass correlation coefficients of 0.97, 0.93, 0.90, and 0.78, respectively). In addition, good agreement was found between continuous wave Doppler measurements of aortic ejection and tricuspid regurgitation velocities (intraclass correlation coefficients of 0.96 and 0.80). However, there was a significant difference between patients with tricuspid regurgitation measured with the hand held device (25.5%) and by standard echocardiography (65.3%), resulting in misdiagnosis of eight patients with pronounced pulmonary hypertension.

CONCLUSIONS

New hand held devices with Doppler capabilities overcome previous limitations in evaluating haemodynamic variables. With colour Doppler they are now suitable for the complete evaluation of valvar disease and diastolic function. However, important limitations remain in the evaluation of pulmonary pressures.

Impression cytology of the conjunctival epithelium after antiglaucomatous treatment with latanoprost

PURPOSE

To study nongoblet and goblet epithelial conjunctival cells after several treatment periods with latanoprost, a prostaglandin analogue.

METHODS

Twelve patients (20 eyes) were studied before the onset of treatment and after 1, 3, and 6 months of latanoprost use. Impression cytology was carried out to analyze cellular density and morphologic parameters such as minimum and maximum diameter and area.

RESULTS

Nongoblet epithelium cell density did not change over the treatment period. The density of goblet cells increased after 1 month of use, but returned to initial cell density after longer treatment periods. Nongoblet epithelial cells underwent a significant reduction in size after 1, 3, and 6 months of treatment. In addition, the minimum/maximum diameter ratio suggested that after 1 month there were some changes in shape (a slight elongation) when compared to cells of untreated patients. Nevertheless, after longer treatment periods, the cells regained their original shape. No changes in size were observed in goblet cells, except for a slight decrease in maximum diameter after 6 months of treatment, which suggests that the cells became more rounded.

CONCLUSIONS

The density of nongoblet epithelial cells does not change after different treatment periods with latanoprost. However, their size decreases and after short treatment periods their shape also undergoes changes. The density of goblet cells increases after 1 month of treatment, but decreases again after longer periods. Their size does not undergo any modification, although there is a variation in shape after 6 months of treatment.

Expression and regulation of scavenger receptor class B type I (SR-BI) in gall bladder epithelium

BACKGROUND AND AIMS

Biliary lipid absorption by the gall bladder mucosa and the cholesterol content of the gall bladder wall appear to play a role in cholesterol gall stone formation. As the scavenger receptor class B type I (SR- BI) regulates cellular cholesterol uptake, we studied its expression in human and murine gall bladders, its regulation by increased biliary lipid content, and its role in gall stone formation.

METHODS AND RESULTS

Using immunohistochemistry, SR-BI was found in the apical domain of human gall bladder epithelial cells. Immunoblotting of isolated membranes from gall bladder epithelial cells showed a specific signal for the 82 kDa SR-BI protein. In C57BL/6 mice, SR-BI was also found in the gall bladder epithelium. Using western blot analysis, an inverse relationship was observed between biliary cholesterol concentration and SR-BI expression in murine gall bladder mucosa. By comparing lithogenic diet fed wild-type and SR-BI deficient mice, gall bladder wall cholesterol content and gall stone formation were not found to be dependent on SR-BI expression.

CONCLUSIONS

(i) SR-BI is expressed in both human and murine gall bladder epithelium; (ii) biliary cholesterol hypersecretion is associated with decreased gall bladder SR-BI expression in mice; and (iii) murine SR-BI is not essential in controlling gall bladder wall cholesterol content and gall stone formation during diet induced cholelithiasis.

Thyroid hormone and uncoupling proteins

Thyroid hormone (TH/T3) exerts many of its effects on energy metabolism by affecting gene transcription. However, although this is an important target for T3, only a limited number of T3-responsive genes have been identified and studied. Among these, the genes for uncoupling proteins (UCPs) have attracted the interest of scientists. Although the role of UCP1 seems quite well established, uncertainty surrounds the physiological function of the recently discovered UCP1 analogs, UCP2 and UCP3. The literature suggests that T3 affects both the expression and the activity of each of these UCPs but further studies are needed to establish whether the mechanisms activated by the hormone are the same. Recently, because of their larger range of expression, much attention has been devoted to UCP2 and UCP3. Most detailed studies on the involvement of these proteins as mediators of the effects of T3 on metabolism have focused on UCP3 because of its expression in skeletal muscle. T3 seems to be unique in having the ability to stimulate the expression and activity of UCP3 and this may be related to the capacity of T3 to activate the integrated biochemical processes linked to UCP activity, such as those related to fatty acids, coenzyme Q and free radicals.

Alendronate daily, weekly in conventional tablets and weekly in enteric tablets: preliminary study on the effects in bone turnover markers and incidence of side effects

Bisphosphonates are now in the vanguard of osteoporosis treatment. Frequently, gastro-oesophageal symptoms are associated with these drugs. The objective of this study was to compare side effects and bone turnover markers in postmenopausal women who had received alendronate daily or weekly in tablets with or without enteric coating. We conducted a randomised, double-blind, 3-month trial. The trial involved 75 volunteers, aged 45-58 with moderate to severe osteopenia (T-score lower than -2 SD) assessed by quantitative ultrasound. Women were assigned randomly to receive: (a) alendronate 10mg/day: (b) alendronate 70 mg once a week: or (c) enteric alendronate 70 mg per week. We recorded side effects, C-telopeptide, osteocalcin and urine hydroxyproline at the start of the study and at 3 months. After 3 months, pyrosis (heartburn) was noted by seven women in group A (28%), three in group B (12%) and two in group C (8%); nausea: by one woman in group B; and headache by one patient in each group. C-telopeptide (A: 40.7%; B: 34.1% and C: 38.5%); hydroxyproline (A: 31.1%;B: 25.3% and C: 31.5%) and osteocalcin (A: 27.0%; B: 25.4% and C: 25.1%) decreased similarly in the three groups. Weekly intake of alendronate, whether conventional or enteric-coated; is associated with less heartburn and nausea. Enteric alendronate has a similar action to the conventional tablets on biochemical markers.

Uncoupling proteins-2 and 3 influence obesity and inflammation in transgenic mice

OBJECTIVE

To test the hypothesis that either uncoupling protein-2 UCP2 or UCP3 or both together influence obesity and inflammation in transgenic mice.

DESIGN

We generated 12 lines of transgenic mice for both human UCP2 and 3 using native promoters from a human bacterial artificial chromosome (BAC) clone. The BAC expresses no genes other than UCP2 and 3. Mice used for experiments are N4 or higher of backcross to C57BL/6J (B6). Each experiment used transgenic mice and their nontransgenic littermates.

RESULTS

Northern blots confirmed expression on human UCP2 in adipose and spleen, while human UCP3 expression was detectable in gastrocnemius muscle. Western blots demonstrated a four-fold increase of UCP2 protein in spleens of Line 32 transgenic animals. Heterozygous mice of four lines showing expression of human UCP2 in spleen were examined for obesity phenotypes. There were no significant differences between Lines 1 and 32, but female transgenics of both lines had significantly smaller femoral fat depots than the control (littermate) mice (P=0.015 and 0.005, respectively). In addition, total fat of transgenic females was significantly less in Line 1 (P=0.05) and almost significantly different in Line 32 (P=0.06). Male Line 1 mice were leaner (P=0.04) while male Line 32 mice were almost significantly leaner (P=0.06). Heterozygous mice of Lines 35 and 44 showed no significant differences from the nontransgenic littermate controls. Effects of the UCP2/UCP3 transgene on obesity in Line 32 mice were confirmed by crossing transgenic mice with the B6.Cg-Ay agouti obese mice. B6.Cg-Ay carrying the UCP2/UCP3 transgene from Line 32 were significantly leaner than nontransgenic B6.Cg-Ay mice. Line 32 UCP2/UCP3 transgenics showed increased hypothalamic Neuropeptide (NPY) levels and food intake, with reduced spontaneous physical activity. Transgenic baseline interleukin4 (IL-4) and interleukin6 (IL-6) levels were low with lower or later increases after endotoxin injection compared to wild-type littermates. Endotoxin-induced fever was also diminished in transgenic male animals. Low-density lipoprotein (LDL) cholesterol levels were significantly higher in both Line 1 and 32 transgenics (P=0.05 and 0.001, respectively) after they had been placed on a moderate fat-defined diet containing 32% of calories from fat for 5 weeks.

CONCLUSION

Moderate overexpression of UCP2 and 3 reduced fat mass and increased LDL cholesterol in two independent lines of transgenic mice. Thus, the reduced fat mass cannot be due to insertional mutagenesis since virtually identical fat pad weights and masses were observed with the two independent lines. Line 32 mice also have altered inflammation and mitochondrial function. We conclude that UCP2 and/or 3 have small but significant effects on obesity in mice, and that their mechanism of action may include alterations of metabolic rate.

[Antiretroviral therapy from 1996-2000]

A retrospective study was carried out from September 1996 to June 2000 and examined the antiretroviral therapies prescribed to HIV patients in whom the viral load had been determined. Triple therapy was the most frequently prescribed during the study and the annual percentage increased to 60% in the last semesters analyzed. Large variability in antiretroviral combinations was observed and depended on the clinical center and unit. The number of individuals who began viral-load monitoring before being treated with antiretroviral drugs showed a progressive increase.

Is thiopurine methyltransferase genetic polymorphism a major factor for withdrawal of azathioprine in rheumatoid arthritis patients?

OBJECTIVE

To determine whether the presence of thiopurine methyltransferase (TPMT) alleles associated with reduced or absent activity of thiopurine methyltransferase is a major factor for withdrawal of azathioprine (AZA) in rheumatoid arthritis (RA) patients.

METHODS

The TPMT genotype, including the variable number of tandem repeats (VNTR) pattern in the 5' untranslated region, was analysed in 111 patients with long-standing RA. Azathioprine (AZA) therapy was used in 40 patients (36%) as a disease-modifying anti-rheumatic drug.

RESULTS

Seven out of 111 RA patients (6.3%) were carriers of a mutant allele, TPMT3A (G(460)-->A, A(719)-->G) being the mutant allele observed most frequently. In the group of 40 AZA-treated patients, therapy was discontinued in six patients because of side-effects and in 26 patients because of lack of efficacy. Three patients presented moderate side-effects and were homozygous for the wild-type TPMT allele, whereas the remaining three patients, who developed gastrointestinal effects with severe nausea and vomiting, were TPMT3A carriers.

CONCLUSION

In this observational study, the absence of response, probably due to the low-dose scheme used, was the major cause of AZA withdrawal in our series of RA patients. TPMT genotyping may allow the use of high doses of AZA in patients with normal TPMT alleles to improve the efficacy of this immunosuppressive drug. Our data support the relationship between gastrointestinal intolerance and thiopurine metabolic imbalance.

Skeletal muscle mitochondrial free-fatty-acid content and membrane potential sensitivity in different thyroid states: involvement of uncoupling protein-3 and adenine nucleotide translocase

The effect of triiodothyronine (T3) on mitochondrial efficiency could be related to an increase in the concentrations of some proteins, such as uncoupling proteins (UCPs). Free fatty acids (FFA) seem to be a cofactor essential for the uncoupling activity of UCP3. In this paper, we report that the hypothyroidism-hyperthyroidism transition is accompanied by increases: (i) in the endogenous levels of mitochondrial FFA and (ii) in the sensitivity to FFA shown by the mitochondrial respiration rate and membrane potential, which correlated with the level of UCP3 protein. The level of the mRNA for adenine-nucleotide translocase-1 (ANT) was not affected by the thyroid state, while the ANT contribution to FFA-induced changes in mitochondrial uncoupling was low in the hypothyroid and euthyroid states but became more relevant in the hyperthyroid state at the highest concentration of FFA.

[Ischemic cadiopathy in patients undergoing chronic hemodialysis]

We report a retrospective study of patients on chronic hemodialysis in whom a diagnosis of ischemic heart disease had been established. We compared the findings on coronary cineangiography and the treatment (medical only, surgical revascularisation [CABG] and percutaneous transluminal coronary angioplasty [PTCA]) with the early and late evolution. From a population of 2,287 patients on chronic hemodialysis treatment during the 5 year period 1994-1999, 83 patients who underwent coronary cineangiography after starting dialysis were selected. Their mean age was 63 +/- 9.4 (39-80) and the mean time on hemodialysis was 6 years (6 months-19 years).

RESULTS

65 patients (78%) had severe coronary lesions, 40% of whom had three vessel disease. 14 patients had medical treatment only (group 1), 23 had CABG (group 2) and 28 PTCA (group 3). Mortality within 30 days of intervention was 13% in group 2 and 21.4% in group 3. Global survival at two years was 82% in group 2 and 69% in group 3. Survival without angina at 6 and 24 months were 69% and 46% in group 2 and 55% and 22% in group 3 respectively. Survival without acute myocardial infarction at 6 and 24 months was 95% and 95% in group 2 and 89% and 64% in group 3. Data analysis using Cox proportional risk model showed that PTCA posed a higher risk of angina and death than CABG.

CONCLUSION

Surgery yielded better early and later results than angioplasty even in those patients with severe coronary artery disease.

Results of an orthopaedic survey in young patients with severe haemophilia in Spain

This paper outlines the results obtained in a cross-sectional study of a group of young patients with severe haemophilia A and B. The primary aim of the study was to ascertain the level of orthopaedic complications in the group, the effects that these complications have on quality of life, and the medical resources used on these patients. The secondary aim was to relate their current orthopaedic state to the type of treatment received before the study. The study was carried out in 11 hospitals in Spain, where 70 severe haemophilia patients (factor VIII [FVIII] < 2%), with an average age of 21.6 and a median age of 22, and no inhibitors, were monitored. The percentage of patients suffering from articular complaints was 84.3% and 85.7% according to the Gilbert and Petterson scales, respectively. Furthermore, pain was reported in 16.1% of joints, most frequently in ankles. Using the SF-36 Health Survey, patients were observed to have a poorer quality of life relative to healthy controls. Despite high levels of both the coagulant factor given to patients and the financial resources dedicated to their treatment, the type of treatment (on demand and/or as secondary prophylaxis) provided to the young adults was found to be incapable of preventing haemophilic arthropathy and subsequent negative quality of life consequences.

Control of energy metabolism by iodothyronines

One of the most widely recognized effects of thyroid hormones (TH) in adult mammals is their influence over energy metabolism. In the past, this has received much attention but, possibly because of the complex mode of action of thyroid hormones, no universally accepted mechanism to explain this effect has been put forward so far. Significant advances in our understanding of the biochemical processes involved in the actions of TH have been made in the last three decades and now it seems clear that TH can act through both nuclear-mediated and extranuclear-mediated pathways. TH increase energy expenditure, partly by reducing metabolic efficiency, with control of specific genes at the transcriptional level, being is thought to be the major molecular mechanism. However, both the number and the identity of the thyroid-hormone-controlled genes remain unknown, as do their relative contributions. The recent discovery of uncoupling proteins (UCPs) (in addition to UCP1 in brown adipose tissue) in almost all tissues in animals, including humans, has opened new perspectives on the understanding of the mechanisms involved in the regulation of energy metabolism by thyroid hormones. Other approaches have included the various attempts made to attribute changes in respiratory activity to a direct influence of thyroid hormones over the mitochondrial energy-transduction apparatus. In addition, an increasing number of studies has revealed that TH active in the regulation of energy metabolism include not only T3, but also other iodothyronines present in the biological fluids, such as 3,5-diiodothyronine (3,5-T2). This, in turn, may make it possible to explain some of the effects exerted by TH on energy metabolism that cannot easily be attributed to T3.

Student perceptions of clinical mistreatment

This study examined radiography students' perceptions regarding mistreatment during the clinical portion of their education. Results suggest that a majority of students perceived mistreatment and that second-year students were 4 times more likely to perceive mistreatment than first-year students. Most students who perceived mistreatment indicated that the abuse was verbal and came primarily from staff technologists. Most perceived the mistreatment to be slightly important and slightly upsetting. However, approximately one third perceived the mistreatment to be very important and very upsetting. As part of the study, students were asked to suggest preventive measures that could help eradicate abusive behavior in the clinical setting.

Intraoperative electron beam radiotherapy during radical surgery for locally advanced and recurrent cervical cancer

OBJECTIVE

The goal of this study was to determine the toxicity patterns and clinical usefulness of intraoperative electron beam radiotherapy (IOERT) in patients with unfavorable-outcome cervical cancer.

METHODS

From January 1986 to June 1999, 67 patients (36 recurrent, 31 primary disease) were treated with IOERT. Previously unirradiated patients received preoperative chemoradiation to 45 Gy with cisplatin 20 mg/m(2) and 5-fluorouracil 1000 mg/m(2). IOERT median dose was 12 Gy for primary disease (range: 10-25) and 15 Gy for recurrent disease (range: 10-20).

RESULTS

The 10-year control rate within the area treated with IOERT ("in-field" (IF)) for the entire group was 69.4, with 92.8 and 46.4% 10-year IF control rates for the primary and recurrent patients, respectively. IF control rate correlated with involvement of the parametrial margin (P = 0.001), amount of residual disease (P = 0.001), and pelvic lymph node involvement (P = 0.032). The overall incidence of toxic events that might be attributable to IOERT was 14.9%. Chronic pain was observed in 8 of 67 evaluable patients (11.9%) and motor neuropathy of the lower extremity in one patient (3.2%).

CONCLUSIONS

IOERT is a valuable boosting technique in the management of advanced but resectable cervical cancer. Patients, especially recurrent cases, with positive lymph nodes, parametrial involvement, and/or incomplete resections have poor local control rates despite IOERT at the doses used in this study.

Uncoupling protein-3 is a molecular determinant for the regulation of resting metabolic rate by thyroid hormone

Thyroid hormones increase energy expenditure, partly by reducing metabolic efficiency. The control of specific genes at the transcriptional level is thought to be the major molecular mechanism. However, both the number and the identity of the thyroid hormone-controlled genes remain unknown, as do their relative contributions. Uncoupling protein-3, a recently identified member of the mitochondrial transporter superfamily and one that is predominantly expressed in skeletal muscle, has the potential to be a molecular determinant for thyroid thermogenesis. However, changes in mitochondrial proton conductance and resting metabolic rate after physiologically mediated changes in uncoupling protein-3 levels have not been described. Here, in a study on hypothyroid rats given a single injection of T(3), we describe a strict correlation in terms of time course between the induced increase in uncoupling protein-3 expression (at mRNA and protein levels) and decrease in mitochondrial respiratory efficiency, on the one hand, and the increase in resting metabolic rate, on the other. First, we describe our finding that uncoupling protein-3 is present and regulated by T(3) only in metabolically relevant tissues (such as skeletal muscle and heart). Second, we follow the time course (at 0, 6, 12, 24, 48, 65, 96, and 144 h) of both uncoupling protein-3 mRNA levels and mitochondrial uncoupling protein-3 density in gastrocnemius muscle and heart. In both tissues, the maximal (12-fold) increase in uncoupling protein-3 density was reached at 65 h. The resting metabolic rate [lO(2)(kg(0.75))(-1)h(-1)] showed the same time course, and at 65 h the increase vs. time zero was 45% (1.316 +/- 0.026 vs. 0.940 +/- 0.007; P < 0.001). At the same time point, gastrocnemius muscle mitochondria showed a significantly higher nonphosphorylating respiration rate (nanoatoms of oxygen per min/mg protein; increase vs. time zero, 40%; 118 +/- 4 vs. 85 +/- 9; P < 0.05), whereas the membrane potential decreased by 8% (168 +/- 2 vs. 182 +/- 4; P < 0.05). These data are diagnostic of mitochondrial uncoupling. The results reported here provide the first direct in vivo evidence that uncoupling protein-3 has the potential to act as a molecular determinant in the regulation of resting metabolic rate by T(3).