Lymphoscintigraphic identification of sentinel lymph nodes: clinical evaluation of 0.22-micron filtration of Tc-99m sulfur colloid

PURPOSE: To evaluate the use of 0.22-micron filtration of technetium-99m sulfur colloid particles in the optimization of lymphoscintigraphy. MATERIALS AND METHODS: Forty-one consecutive lymphoscintigraphic studies obtained with 0.22-micron filtration of Tc-99m sulfur colloid in 41 patients (26 men, 15 women; average age, 55.4 years) and 41 consecutive studies obtained with 5.0-micron filtration in 41 patients (20 men, 21 women; average age, 54.5 years) were retrospectively, randomly reviewed. Studies were evaluated for lymphatic channel depiction and sentinel lymph node depiction. Studies included immediate flow images (obtained at 10 seconds per frame) and multiview static images obtained up to 2 hours after intradermal Tc-99m sulfur colloid injection. RESULTS: The number of drainage beds visualized was 52 with 5.0-micron filtration and 51 with 0.22-micron filtration (P = .570). The number of lymphatic channels visualized was 45 with 5.0-micron filtration and 75 with 0.22-micron filtration (P = .006). The number of lymph nodes visualized was 102 with 5.0-micron filtration and 123 with 0.22-micron filtration (P = .123). The number of studies judged as optimal (i.e., depicted lymphatic channels leading to sentinel nodes) was 10 with 5.0-micron filtration and 19 with 0.22-micron filtration (P = .038). The number of studies with depicted lymph nodes but no depicted lymphatic channel was 15 with 5.0-micron filtration and six with 0.22-micron filtration (P = .023). CONCLUSION: The use of 0.22-micron filtration in the preparation of Tc-99m sulfur colloid substantially improves study quality and increases the diagnostic certainty in the identification of sentinel lymph nodes.     

Electroneutral Na-coupled cotransporter expression in the kidney during variations of NaCl and water metabolism

The antiproteinuric effect of angiotensin converting enzyme (ACE) inhibition in insulin-dependent diabetes mellitus (IDDM) patients with diabetic nephropathy varies considerably. Therefore, we tested the potential role of an insertion (I)/deletion (D) polymorphism of the ACE gene on this early antiproteinuric responsiveness in an observational follow-up study. Sixty (II, N = 13; ID, N = 26 and DD, N = 21) young hypertensive IDDM patients suffering from diabetic nephropathy were investigated during three months before and for the initial six month period during ACE inhibition [captopril 44 (SD 22) mg/24 hr, no differences in drug dose between groups]. Blood pressure (MABP) and albuminuria (ELISA) were measured three (1 to 6) times before and three (1 to 13) times during ACE inhibition. At baseline the groups (II/ID/DD) had comparable (1) mean arterial blood pressure (MABP mm Hg) of 113 +/- 10/108 +/- 9/114 +/- 8, (2) albuminuria (geometric mean with 95% CI) 1394 (747 to 2608)/1176 (844 to 1797) and 1261 (827 to 2017) mg/24 hr, and (3) serum creatinine (geometric mean with 95% CI), 80 (68 to 93)/85 (76 to 97)/103 (85 to 119) mumol/liter, respectively. Angiotensin converting enzyme inhibition induced a significant reduction in MABP, albuminuria and kidney function in all three groups (II/ID/DD; P < 0.05): (1) MABP (mean +/- SD) 12 +/- 7/5 +/- 7/8 +/- 9 mm Hg (ANOVA, P = 0.02); (2) albuminuria [mean (95% CI)] 61 (34 to 77)/22 (3 to 37)/31 (13 to 46) %, (ANOVA, P < 0.01); and (3) increasing serum creatinine [mean (95% CI)] 8 (4 to 12)/9 (3 to 16)/8 (0 to 16) % (ANOVA, NS), respectively. Adjusting for differences in reduction in MABP did not change the association between decrease in albuminuria and ACE/ID genotypes (P < 0.01). A multiple linear regression analysis revealed that the ACE/ID polymorphism, albuminuria and MABP at baseline independently influenced the decline in albuminuria after initiation of ACE inhibition (R2 = 0.21, P < 0.01). A significant association between changes in MABP and albuminuria was demonstrated (R2 = 0.16, P < 0.01). Our data show that hypertensive albuminuric IDDM patients with the II genotype are particularly susceptible to commonly advocated renoprotective treatment.     

An effective analytical psychotherapy in crosscultural context. An East Asian student in the United States

Nucleoside triphosphate hydrolase is an abundant protein secreted by the obligate protozoan parasite Toxoplasma gondii. The protein has apyrase activity, degrading ATP to the di- and mono-phosphate forms. Because T. gondii is incapable of de novo synthesis of purines, it is postulated that NTPase may be used by the parasite to salvage purines from the host cell for survival and replication. To elucidate the molecular mechanisms of NTP gene expression, we isolated from the virulent RH strain of T. gondii the putative promoter region of three tandemly repeated NTP genes (NTP1, 2, 3). Using deletion constructs linked to the chloramphenicol acetyl transferase (CAT) reporter gene, we defined an active promoter within the first 220 bp. Sequence analysis of this region reveals the lack of a TATA box, but the promoter region is associated with a sequence which resembles an initiator element (Inr) in the NTP1 and NTP3 genes. This sequence which is similar to other Inrs known to regulate the expression of a wide variety of RNA polymerase II genes, is required for NTP expression. The NTP3 promoter contains sufficient information for developmentally regulated expression of CAT activity when the actively replicating stage tachyzoite differentiates into the dormant bradyzoite form.     

Platelet adhesion on a polyurethane surface grafted with a zwitterionic monomer of sulfobetaine via a Jeffamine spacer

A possible approach to improve the blood compatibility of poly(ether urethane)s (PU) involves the covalent attachment of key molecules on its surface. The purpose of the present study was to design and synthesise a novel non‐thrombogenic biomaterial by modifying the surface of the PU with a zwitterionic monomer of sulfobetaine via a Jeffamine spacer. In this study, sulfobetaine was grafted onto a PU surface through the following reaction steps: (1) The PU surface was activated with hexamethylene diisocyanate (HDI) in toluene at 50 °C in the presence of di‐n‐butyltin dilaurate (DBTDL) as a catalyst. The extent of the reaction was measured by ATR‐FTIR spectra; a maximum number of free NCO groups was obtained after a reaction time of 90 min. (2) One cap of Jeffamine was reacted with isocyanate groups bound on the surface, so Jeffamine was introduced. (3) The PU surface terminated by Jeffamine was recoupled with isocyanate groups by HDI. (4) The hydroxyl groups of 4‐dimethylamino‐1‐butanol (DMAB) or 2‐dimethylaminoethanol (DMAE) were allowed to react with the isocyanate groups capped on Jeffamine. (5) Sulfobetaines were constructed on the surface through the ring‐opening reaction between tertiary amine and 1,3‐propanesultone (PS). It was confirmed by ATR‐FTIR and XPS that the grafted surfaces were composed of sulfobetaine. The results of the contact‐angle measurements and water absorption showed that they were strongly hydrophilic. The results of this platelet adhesion experiment as a preliminary test showed that PU grafted with sulfobetaine has good blood compatibility featured by the low platelet adhesion. Copyright © 2004 Society of Chemical Industry     

Arch-length asymmetry related to an odontoma in a three-year-old

Hypothyroidism developed in a neonate following the excision of a large cervical teratoma. This finding supports the observation that cervical teratomas commonly arise from thyroid tissue. Thyroid function tests should be performed routinely in all patients in whom identifiable residual thyroid tissue is not demonstrated at the conclusion of the operation.     

Transthoracic Doppler echocardiography of normally originating coronary arteries in children

Transthoracic Doppler color flow and spectral velocity patterns of normal coronary arteries in children have not been well studied. We designed this study to evaluate coronary artery flow velocity characteristics in normal and hypertrophied hearts. Sixty-eight children with optimal two-dimensional echocardiographic images of the left coronary artery (LCA) and right coronary artery (RCA) were prospectively studied. The heart was normal in 45 children, and 23 had left and/or right ventricular hypertrophy assessed by echocardiography (mean age 5.8 versus 5.2 years, p = NS). Color flow signals were detected in the LCA in 63(92%) of the 68 children studied, and pulsed Doppler spectral waveforms were recorded in 47 (69%). The latter were recorded in 26 (58%) of 45 normal children and in 21 (91%) of 23 children with left ventricular hypertrophy. Diastolic RCA flow signals were detected mostly in those with right ventricular hypertrophy (10 of 10). Higher levels of LCA maximum diastolic velocity (42 +/- 23 versus 24 +/- 6 cm/sec, p = 0.0004), increased diastolic flow (16 +/- 15 versus 6 +/- 4 ml/min, p = 0.01), and delayed time to peak diastolic velocity expressed as a percentage of diastolic spectral duration (38% +/- 14% versus 20% +/- 8%, p = 0.0001) were observed in children with left ventricular hypertrophy than in those in normal children. A strong correlation was present between Doppler-derived LCA flow and left ventricular mass/m2 (r = 0.7, p = 0.001). In normal hearts, LCA spectral velocity pattern did not change with increasing age, but the time velocity integral became progressively larger, resulting in a strong correlation with weight (p < 0.001, r = 0.78). This study demonstrates (1) LCA flow signals can be detected and quantitated in the majority of children with and those without left ventricular hypertrophy. (2) Left ventricular hypertrophy is associated with increased LCA flow, higher diastolic velocity, and delayed peak diastolic velocity. (3) RCA flow signals are mostly detected when there is right ventricular hypertrophy. Studies on larger groups of patients are needed to further confirm our observations and to enhance understanding of coronary artery flow reserve.     

Solubility of amino acids and diglycine in aqueous-alkanol solutions

The solubility of glycine and dl-alanine were measured in the temperature range between 25°C and 60°C for the aqueous systems of ethanol, 1-propanol and 2-propanol. The analytical gravimetric method was chosen to perform the measurements and proved to be very accurate. Theoretical work was essentially focused on the application of the excess solubility approach with the NRTL model showing average relative deviations around 8.4% for correlation and 15% for predictions.     

Context-based LZW encoder

The context-based encoding concept is used to propose new versions of the Lempel-Ziv-Welch (LZW) encoder. The practical performance of these new versions is measured using the Canterbury Corpus and it is shown that this concept, if properly used, can lead to an improvement around 10%