Detection of moderate and severe coronary artery stenosis with technetium-99m tetrofosmin myocardial single-photon emission tomography

The aim of this study was to determine the diagnostic accuracy of technetium-99m tetrofosmin myocardial imaging for the localization of coronary artery stenoses of different degrees of severity. Stress-rest single-photon emission tomography (SPET) was performed on separate days in 80 patients (64 males, 16 females; mean age 61 years; 43 patients with previous myocardial infarction; 18 patients with pharmacological stress), within 6 months of coronary angiography. Scintigraphic images were blindly and independently evaluated by three observers. Coronary stenosis was defined as a >50% narrowing in luminal diameter; severe stenosis was defined as a proximal stenosis of >75% or a peripheral stenosis of >90%. Coronary angiography revealed normal coronary arteries or insignificant coronary stenosis in 13 patients and significant coronary stenoses in 67 patients. The sensitivity and specificity of ^99mTc-tetrofosmin SPET in respect of severely stenosed vessels were, respectively, 80% and 65% for the left anterior descending artery (LAD), 100% and 46% for the right coronary artery (RCA) and 58 and 78% for the left circumflex artery (LCx) territories. Considering all the significantly stenosed vessels, a significant decrease in sensitivity was observed for LAD territories (to 59%, P=0.05), and a nonsignificant decrease for RCA (88%) and LCx (47%) territories while specificity values remained essentially unchanged. No significant changes in sensitivity or specificity were observed when regions with previous myocardial infarction were excluded. In conclusion, the sensitivity of ^99mTc-tetrofosmin SPET for the localization of individual stenosed vessels is only moderate when all significant stenoses are considered, but the ability of this technique to predict the location of severe coronary artery stenoses seems satisfactory, with the exception of the low specificity in respect of RCA territories. Received 26 April and in revised form 7 June 1997     

Scalp and Limbic P3 Event-Related Potentials in the Assessment of Patients with Temporal Lobe Epilepsy

Auditory oddball scalp and limbic P3s were recorded from 18 patients with unilateral temporal lobe epilepsy (TLE) prior to seizure surgery. Limbic P3s were unilaterally absent ipsilateral to the seizure focus and were present in the nonepileptogenic temporal lobe in all 18 cases studied. Scalp P3s, recorded from C3 and C4, on the other hand, were elicited bilaterally and there was no significant difference in amplitude or latency between the epileptogenic and nonepileptogenic sides. These data concur with studies of scalp P3 performed following surgery and suggest that the assessment of the contribution of limbic P3 to scalp P3 may be masked by volume conduction effects and other generators of P3. We conclude that the P3 recorded from central scalp sites, unlike its limbic counterpart, offers little clinical information in the presurgical assessment of patients with TLE.     

Effect of trauma on malaria infection

Specific malaria antibody concentrations in the sera of Nigerian patients were estimated before and after elective surgery by the microplate version of the enzyme-linked immunoabsorbent assay (ELISA). Parasitized erythrocytes per 100 leukocytes in Leishman-stained tail blood smears were also counted on the pre- and early post-trauma days in traumatized and non-traumatized (control) laboratory mice previously inoculated withPlasmodium berghei malaria parasites. On the 1st, 2nd, and 3rd postoperative days, specific malaria antibody levels in the sera of Nigerian patients were significantly depressed (p<0.02;p<0.01;p<0.001, respectively) while parasitemia was significantly elevated in laboratory mice with fractured femur (p<0.02;p<0.01;p<0.05, respectively). Increased susceptibility to malaria after severe injury is suggested.     

Zuckerkandl's tubercle of the thyroid gland in association with pressure symptoms: a coincidence or consequence?

BACKGROUND: The Zuckerkandl's tubercle (ZT) of the thyroid gland is a well-described anatomical landmark, but few studies have clearly defined its association with pressure symptoms. METHODS: Sixty-six consecutive patients who had primary thyroid surgery were prospectively included in the present study between late January and early August 1998. RESULTS: A total of 96 capsular dissections were performed at thyroid surgery. Grades two and three ZT were recognized in 77 (80.2%) dissections. In general 49 (63.6%) of them were associated with significant pressure symptoms. In 43 (87.8%) of the dissections with pressure symptoms, grade 3 ZT was observed (mean weight of goitre: 154.8 g). Interestingly in this group, 16 (37.2%) patients with pressure symptoms had a goitre that was < 100 g and in one patient it was only 21 g. CONCLUSIONS: The pressure symptom of the thyroid gland does not always appear to be due to the large size of the goitre. In a relatively small-size goitre the ZT may cause significant pressure symptoms. Observations in the present study supported a strong association of enlarged ZT with pressure symptoms. We believe this is unlikely to be simply a coincidence but rather a consequence of the enlarged tubercle. Nonetheless a prospective randomized study is called for to allow meaningful and objective evidence to be drawn.     

Effect of volume of porogens on the porosity of PLGA scaffolds in pH-controlled environment

Poly(lactic-co-glycolic acid) (PLGA) is a well-studied biodegradable polymer used in drug delivery and other medical applications such as in tissue regeneration. It is often necessary to impart porosity within the scaffold (microparticles) in order to promote the growth of tissue during the regeneration process. Sodium chloride and ammonium bicarbonate have been extensively used as porogens in the generation of porous microstructure. In this study, we compared the effect of volumes (250?μl, 500?μl and 750?μl) of two porogens, sodium chloride (1.71 M) and ammonium bicarbonate (1.71 M), on the porosity of PLGA microparticles.     

Hepatitis C prevalence among the migrant population in Spain: A systematic review and meta-analysis

Introduction

Spain, which has one of the largest migrant populations in Europe, has committed to eliminating the hepatitis C virus (HCV). The aim of this study was to estimate the prevalence of HCV among migrant groups in Spain, a country of 46 million people, with an estimated HCV-antibody prevalence of 1.7%.