Trastuzumab associated with successive cytotoxic therapies beyond disease progression in metastatic breast cancer

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Background: Whether trastuzumab should be continued after tumor progression remains unknown.We describe the activity of successive trastuzumab-containing regimens in patients with HER2-overexpressing metastatic breast cancer, as well as the response rate, time to progression and predictive factors for response. Methods: Descriptive retrospective study of trastuzumab activity in patients with HER2-overexpressing metastatic breast cancer treated at our hospital from 10/1999 to 07/2005. Results: 93 consecutive patients were evaluated obtaining an objective response rate (OR) for first-time administration of trastuzumab of 46.2%; stable disease (SD) 24.7%; clinical benefit (CB) 71%. Median time-to-progression (TTP) was 5 months (range: 1–39+). A total of 47 pts (50.5%) received a second trastuzumab-containing regimen with an OR of 29.8%; SD 21.3%; CB 51.1%; TTP 4 months (range: 1–31). A total of 21 pts (22.6%) received a third trastuzumab-containing regimen; OR 38.1%; SD 23.8%; CB 61.9%; TTP 4 months (range: 1–30+). A total of 10 pts (10.8%) received a fourth trastuzumab-containing regimen; OR 20%; SD 20%; CB 40%; TTP 4 months (range: 1–37). 5 pts (5.4%) received a fifth trastuzumab-containing regimen; OR 0%; SD 60%. Age < 45 years is a significant prognostic factor (p: 0.005, 95% CI, OR 5.6 (1.5–20.6)). A better response rate in the successive trastuzumab-containing regimens was observed, when there was a response in the first regimen: p = 0.04; 95% CI; OR 3.84 (1.07–14.65). With a follow-up of 16,5 months 45 pts (48,4%) are alive. Conclusions: Trastuzumab-containing therapies beyond disease progression in metastatic breast cancer show activity. There were more responses in younger pts. Those pts who had a previous response to trastuzumab therapy were more likely to respond to successive trastuzumab-containing regimens. Additional controlled studies are needed to test this approach.

No significant financial relationships to disclose.

Reduced systolic performance by tissue Doppler in patients with preserved and abnormal ejection fraction: New insights in chronic heart failure

BACKGROUND

Tissue Doppler imaging (TDI) is useful in the evaluation of systolic and diastolic function. It allows assessment of ventricular dynamics in its longitudinal axis. We sought to investigate the difference in systolic and diastolic longitudinal function in patients with chronic heart failure (CHF) with normal and reduced ejection fraction.

METHODS AND RESULTS

One hundred ten outpatients with CHF and 68 controls were included. Ejection fraction (EF) was obtained and longitudinal systolic (S) and diastolic (E' and A') wall velocities were recorded from basal septum. Group A (controls) were normal and CHF patients were classified by EF in Group B1: > 45% and B2: < or = 45%. In A, B1 and B2 the mean S peak was 7.74; 5.45 and 4.89 cm/s (p<0.001); the mean E' peak was 8.56; 5.72 and 6.1 cm/s (p<0.001); and the mean A' peak was 10.2; 7.3 and 5.3 cm/s (p<0.001). Also, isovolumic contraction and relaxation time were different among control and CHF groups, (both p<0.001). The most useful parameters for identifying diastolic CHF were IVRT and S peak, with area under ROC curves of 0.93 and 0.89. The cut-off of 115 ms for IVRT and 5.8 cm/s for S peak showed a sensitivity of 94 and 97%, with a specificity of 82 and 73%, respectively.

CONCLUSION

These findings suggest that impairment of left ventricular systolic function is present even in those with diastolic heart failure, and that abnormalities may have an important role to identifying the condition.

Ex vivo expansion of umbilical cord blood CD34+ cells in a closed system: a multicentric study

BACKGROUND AND OBJECTIVES

The Dideco 'Pluricell System' is a CE-marked medical device allowing haematopoietic stem cell (HSC) expansion. It comprises a kit of cGMP cytokines and reagents, a closed-cell expansion chamber and a cell-washing set. We tested the system in a multicentric study by expanding CD34(+) cells from eight fresh umbilical cord blood (UCB) samples.

MATERIALS AND METHODS

During culture, the mean nucleated cell (NC) count, the mean CD34(+) cell count, fold expansion, viability and apoptosis were measured. Clonogenic assays and immunophenotypical characterization were performed on days 0, 7 and 12. On the expanded cellular product, in three cases cell genotyping, endotoxin level and mycoplasma detection (by polymerase chain reaction) were performed.

RESULTS

The mean CD34(+) cell expansion on days 7 and 12 was sevenfold and 12-fold respectively and the mean NC expansion was 69-fold and 180-fold. The mean NC viability on day 12 was 96.9% (94.4-99.1). After 12 days, granulocyte-macrophage colony-forming units (GM-CFU) showed a 20-fold increase: a slight increase in CD34(+) cell apoptosis was observed during culture. In all of three cases neither chromosomal alterations nor mycoplasma contamination was detected. No significant endotoxin levels were detected after expansion.

CONCLUSIONS

The device allows the ex vivo expansion of NC and CD34(+) cells in a closed system. The expanded cellular product is a mixture of progenitors (CD34(+) cells) and differentiated (mainly myeloid and megakaryocytic) cells. To reduce cell apoptosis, more frequent cell feeding during culture should be tested.

Mitral valve hemodynamic effects of percutaneous edge-to-edge repair with the MitraClip™ device for mitral regurgitation

INTRODUCTION

The Endovascular Valve Edge-to-Edge REpair STudies (EVEREST) are investigating a percutaneous technique for edge-to-edge mitral valve repair with a repositionable clip. The effects on the mitral valve gradient (MVG) and mitral valve area (MVA) are not known.

METHODS

Twenty seven patients with moderate to severe or severe mitral regurgitation (MR) were enrolled. Echocardiography was performed preprocedure, at discharge, and at 1, 6, and 12 months. Mean MVG was measured by Doppler and MVA by planimetry and pressure half-time, and evaluated in a central core laboratory. Pre- and postclip deployment, simultaneous left atrial/pulmonary capillary wedge and left ventricular pressures were obtained in eight patients.

RESULTS

Three patients did not receive a clip, six patients had their clip(s) explanted by 6 months (none for mitral stenosis), and four were repaired with two clips. Results are notable for a slight increase in mean MVG by Doppler postclip deployment (1.79 +/- 0.89 to 3.31 +/- 2.09 mm Hg, P < 0.01) and an expected decrease in MVA by planimetry (6.49 +/- 1.61 to 4.46 +/- 2.14 cm(2), P < 0.001) and by pressure half time (4.35 +/- 0.98 to 3.01 +/- 1.42 cm(2), P < 0.05). There were no significant changes in hemodynamic parameters postclip deployment by direct pressure measurements. There was no change in MVA by planimetry from discharge to 12 months (3.90 +/- 1.90 to 3.79 +/- 1.54 cm(2), P = 0.78).

CONCLUSIONS

Echocardiographic and hemodynamic measurements after percutaneous mitral valve repair with the MitraClip show an expected decrease in mitral valve area with no evidence of clinically significant mitral stenosis either immediately after clip deployment or after 12 months of follow-up.

Percutaneous edge-to-edge mitral valve repair: 2-year follow-up in the first human case

We report the first-in-human mitral valve repair using percutaneous technology that creates a "surgical-like" edge-to-edge repair. A catheter-delivered clip was introduced transseptally from the femoral vein, advanced through the mitral orifice, retracted to grasp the leaflets, and detached to create a functional double-orifice valve. The patient had an uncomplicated post-procedural course. Echocardiography at 1- and 2-years post procedure showed mild mitral regurgitation and positive ventricular remodeling. The success of this case suggests that percutaneous mitral valve repair may be a feasible therapy for certain patients suffering from mitral regurgitation.

Factors associated with insulin discontinuation in subjects with ketosis-prone diabetes but preserved beta-cell function

AIM

To evaluate factors predictive of insulin discontinuation in subjects with ketosis-prone Type 2 diabetes.

METHODS

One hundred and six subjects with ketosis-prone Type 2 diabetes were recruited during the index episode of diabetic ketoacidosis (DKA). All subjects were followed in a special clinic for at least 6 months. If the subject's glycaemic control reached specified glycaemic goals, exogenous insulin was gradually decreased until discontinuation. Baseline and follow-up characteristics were compared between the off-insulin and the on-insulin groups.

RESULTS

At the end of the follow-up period (915+/-375 days) insulin was discontinued in 47% subjects. Subjects in the off-insulin group were significantly older at the time of diagnosis of diabetes. In the off-insulin group the majority of subjects were newly diagnosed with diabetes. After 6 months of follow-up, subjects in the off-insulin group had significantly lower mean HbA(1c), higher mean C-peptide-to-glucose ratio and had more clinic visits per year. In the proportional hazard analysis, new-onset diabetes [hazard ratio (HR) 1.54; 95% confidence interval (CI) 1.02-2.45], and a higher C-peptide-to-glucose ratio at 6 months of follow-up (HR 1.77; 95% CI 1.22-2.63) were significant predictors of insulin discontinuation.

CONCLUSIONS

In subjects with ketosis-prone Type 2 diabetes, the best predictors of insulin discontinuation are having new-onset diabetes, and higher beta-cell functional reserve (as measured by the C-peptide-to-glucose ratio).

Percutaneous Mitral Valve Repair Using the Edge-to-Edge Technique

OBJECTIVES

This study sought to evaluate the clinical results of a percutaneous approach to mitral valve repair for mitral regurgitation (MR).

BACKGROUND

A surgical technique approximating the middle scallops of the mitral leaflets to create a double orifice with improved leaflet coaptation was introduced in the early 1990s. Recently, a percutaneous method to create the same type of repair was developed. A trans-septal approach was used to deliver a clip device that grasps the mitral leaflet edges to create the double orifice.

METHODS

General anesthesia, fluoroscopy, and echocardiographic guidance are used. A 24-F guide is positioned in the left atrium. The clip is centered over the mitral orifice, passed into the left ventricle, and pulled back to grasp the mitral leaflets. After verification that MR is reduced, the clip is released.

RESULTS

Twenty-seven patients had six-month follow-up. Clips were implanted in 24 patients. There were no procedural complications and four 30-day major adverse events: partial clip detachment in three patients, who underwent elective valve surgery, and one patient with post-procedure stroke that resolved at one month. Three additional patients had surgery for unresolved MR, leaving 18 patients free from surgery. In 13 of 14 patients with reduction of MR to < or =2+ after one month, the reduction was maintained at six months.

CONCLUSIONS

Percutaneous edge-to-edge mitral valve repair can be performed safely and a reduction in MR can be achieved in a significant proportion of patients to six months. Patients who required subsequent surgery had elective mitral valve repair or intended replacement.

Predictors of glycaemic control in indigent patients presenting with diabetic ketoacidosis

AIM

To derive predictors of good glycaemic control in patients presenting with diabetic ketoacidosis (DKA) followed prospectively in a specialized clinic.

METHODS

One hundred and sixty-one adult patients were admitted during a 31-month period and followed for at least 12 months. After 1 year, the patients were classified into three groups: good control (GC) (HbA1c < or = 7%), intermediate control (IC) (HbA1c 7-9%) and poor control (PC) (HbA1c > 9%). Characteristics of patients in the three groups were compared both at baseline and during follow-up.

RESULTS

At 12 months, 36% of the patients were classified as GC, 27% as IC and 37% as PC. GC patients had higher fasting serum C-peptide levels 0.7 +/- 0.54 compared to 0.38 +/- 0.29 and 0.16 +/- 0.21 nmol/l, respectively, for the IC and PC patients (p < 0.0001). A higher proportion GC patient had a C-peptide level greater than 0.33 nmol/l than that for IC and PC patients (86, 61 and 19%, respectively; p < 0.0001). Exogenous insulin was safely discontinued in 50, 30 and 3% of patients, respectively, in the GC, IC and PC groups (p < 0.0001). Compliance with life-style interventions was higher in the GC than that in IC and PC patients (87, 41 and 5%, respectively; p < 0.0001). In the logistic regression analysis, predictors of good glycaemic control were having baseline fasting serum C-peptide value > or =0.33 mmol/l, OR: 3.01 (95% CI 1.07-8.55, p = 0.03) and compliance with life-style interventions OR 12.66 (95% CI 3.73-51.57, p = 0.0001).

CONCLUSION

Among adult patients with DKA, significant predictors of good glycaemic control are preserved beta-cell function and compliance with life-style modifications.

Cytotoxic and genotoxic effects of the exposure of human lymphocytes to a calcium phosphate cement in vitro

The cytotoxic and genotoxic effects of a phosphate bone cement on human peripheral lymphocyte cultures exposed for 48 hr were determined. The mitotic index and the integrity of the DNA molecule were used as biocompatibility markers. It was found that the cement was not cytotoxic, but genotoxic at concentrations of >/=100 microg/ml. The cement was also characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). (Journal of Applied Biomaterials and Biomechanics 2005; 3: 29-34).

Human T cell lymphotropic virus type 1 infection and early neurologic development: a pilot study of 48 children

To determine whether human T cell lymphotropic virus type 1 (HTLV-1) infection is associated with delayed neurological development, we examined 48 Peruvian children with exposure to HTLV-1 who were identified at the Instituto Materno-Perinatal. Compared with 38 HTLV-1-seronegative children, the 10 seropositive children did not have higher rates of neurodevelopmental delay. Long-term follow-up is planned.

Rapid determination of alpha emitters using Actinide resin

The European Commission has recently published the recommended radiological protection criteria for the clearance of building and building rubble from the dismantling of nuclear installations. Radionuclide specific clearance levels for actinides are very low (between 0.1 and 1 Bq g(-1)). The prevalence of natural radionuclides in rubble materials makes the verification of these levels by direct alpha counting impossible. The capability of Actinide resin (Eichrom Industries, Inc.) for extracting plutonium and americium from rubble samples has been tested in this work. Besides a strong affinity for actinides in the tri, tetra and hexavalent oxidation states, this extraction chromatographic resin presents an easy recovery of absorbed radionuclides. The retention capability was evaluated on rubble samples spiked with certified radionuclide standards (239Pu and 241Am). Samples were leached with nitric acid, passed through a chromatographic column containing the resin and the elution fraction was measured by LSC. Actinide retention varies from 60% to 80%. Based on these results, a rapid method for the verification of clearance levels for actinides in rubble samples is proposed.

A rapid method to quantify left atrial contractile function: Doppler tissue imaging of the mitral annulus during atrial systole

AIMS

Assess the value of peak atrial systolic mitral annular velocity (Aann) measured by Doppler tissue echocardiography to quantify left atrial systolic function.

METHODS

We studied a total of 61 adults; 10 subjects without history of heart disease and 51 patients with a history of atrial fibrillation or undergoing evaluation for left ventricular systolic or diastolic dysfunction. Aann was obtained by averaging peak atrial systolic mitral annular velocities from the septal, lateral, anterior, and inferior annulus. Left atrial fractional area change (FAC) and fractional volume change (FVC) during atrial systole were calculated. The correlation between peak atrial systolic mitral annular velocity (Aann) and left atrial systolic FAC and FVC was determined.

RESULTS

Mean FAC and FVC were 27 +/- 12 and 40 +/- 14%, respectively; mean Aann was 11.2 +/- 3.2 cm/s. Linear regression analysis showed correlation between Aann and FAC (r = 0.71; p<0.001) and between Aann and FVC (r = 0.74; p<0.001).

CONCLUSIONS

Peak systolic mitral annular velocity correlates well with left atrial systolic FAC and FVC, thus providing an easy means to assess left atrial systolic function.

Dysregulation of endogenous carbon monoxide and nitric oxide production in patients with advanced ischemic or nonischemic cardiomyopathy

Carbon monoxide (CO) and nitric oxide (NO) are endogenous vasoregulatory molecules whose role in heart failure is not fully known. Exhaled CO and NO measurement provide novel noninvasive assessment of their endogenous production. We compared exhaled CO and NO in 24 patients with advanced ischemic and nonischemic cardiomyopathy and in 13 control subjects without known cardiac disease at rest and at 1 and 5 minutes after exercise testing. Exhaled CO was lower in patients with cardiomyopathy at rest (1.66 +/- 0.2 vs 1.80 +/- 0.5 ppm, p = 0.02) and 1 minute after exercise (1.35 +/- 0.2 vs 1.81 +/- 0.5 ppm, p = 0.009), with a similar trend at 5 minutes after exercise (1.45 +/- 0.3 vs 1.81 +/- 0.5 ppm, p = 0.14). Exhaled CO decreased in patients with cardiomyopathy after exercise (p <0.001 and p = 0.02 at rest vs 1 and 5 minutes after exercise, respectively) but was maintained in controls. Exhaled NO did not differ between patients with cardiomyopathy and controls at rest (9.48 +/- 1.4 vs 9.68 +/- 1.5 ppb, p = NS) and after exercise (1 minute: 10.91 +/- 1.8 vs 9.19 +/- 1.2 ppb; 5 minutes: 10.52 +/- 1.5 vs 8.90 +/- 1.2 ppb, p = NS). Exhaled NO increased after exercise in patients with cardiomyopathy (p = 0.01 and p = 0.04 rest vs exercise at 1 and 5 minutes, respectively), but was maintained in controls. Exhaled CO and NO were not correlated with peak oxygen consumption in patients with cardiomyopathy. The differential responses in exhaled CO and NO at rest or with exercise between patients with cardiomyopathy and normal controls may point to dysregulation in endogenous CO and NO production.

Ultrasound-compacted and spray-congealed indomethacin/polyethyleneglycol systems

The product obtained by ultrasound (US)-assisted compaction was compared with a solid dispersion for systems containing polyethyleneglycols (PEGs) of different molecular weights and indomethacin (IMC), at the weight ratio 9:1, obtained by traditional melting and followed by a new US-assisted spray-congealing technique. US-discharge during compaction affects crystallinity of both IMC and PEG: pure IMC changes to an amorphous form and, when in mixture with PEG, partially dissolves in the excipient: this causes an increase of the dissolution rate of the drug. Differential scanning calorimetry (DSC) thermograms do not reveal any endothermic peak associated with the melting of the drug, while X-ray diffractograms show a loss of crystallinity of both IMC and PEG in the US-compacted granules. The extent of a back-crystallisation, which reduces the dissolution rate, as a function of the ageing of the material, depends on the type of the selected PEG. When a molten IMC/PEG mixture was transformed into microspheres by an US-assisted spray-congealing technique, the behaviour at dissolution almost recalls that of US-compacted granulates and some differences are briefly discussed.

Use of intracardiac echocardiography for prediction of chronic pulmonary vein stenosis after ablation of atrial fibrillation

INTRODUCTION

Measurements of pulmonary vein (PV) flow with intracardiac echocardiography (ICE) immediately before and after PV isolation may be a useful method for predicting which patients will develop chronic PV stenosis.

METHODS AND RESULTS

We assessed preablation and postablation flows in each of the four PVs using a phase-array ICE catheter in 95 patients (mean age 52 +/- 13) undergoing atrial fibrillation ablation. The ostium of each of the PVs was defined using angiography, electrical mapping, and ICE imaging. Ostial electrical isolation of all PVs was achieved using a 4-mm cooled-tip radiofrequency ablation catheter. Change in PV flow, when present, was examined as both an absolute value and as a percentage of the baseline flow. All patients underwent spiral computed tomography (CT) scans of the PVs 3 months after the procedure for detection of stenosis. The average preablation diastolic flows for the left superior, left inferior, right superior, and right inferior veins were 0.56, 0.54, 0.47, and 0.45 m/sec, respectively. These values increased to 0.74, 0.67, 0.58, and 0.59 m/sec postablation (P < 0.001). Of 380 PVs ablated, the CT scans revealed 2 (1%) with severe (>70%) stenosis, 13 (3%) with moderate (51%-70%) stenosis, and 62 (16%) with mild (< or = 50%) stenosis. The r value between flow and stenosis was only 0.09 (P = NS).

CONCLUSION

Acute changes in PV flow immediately after ostial PV isolation do not appear to be a strong predictor of chronic PV stenosis.

Preparation and characterization by morphological analysis of diclofenac/PEG 4000 granules obtained using three different techniques

The steam granulation is a new wet granulation technique, which involves the use of steam water instead of traditional liquid water as granulation liquid. The aim of this work was to evaluate the possibility of using this new technique to prepare diclofenac-polyethylene glycol 4000 accelerated-release granules. Steam granules were prepared in a laboratory scale high-shear mixer, and their properties were then compared to those of granules, having the same composition, obtained by traditional granulation techniques (wet and melt granulation). The results showed that, selecting the proper process parameters, it was possible to obtain granules using all the three methods; however, the total process time was significantly shorter for steam granulation (30 min) in comparison to traditional wet granulation (70 min), due to the lower amount of used water. The morphological characterization of steam, water and melt granules, performed by scanning electron microscopy (SEM) and image analysis, revealed that steam granules had a more spherical shape and a larger surface area with respect to water and melt ones, suggesting a possible difference in dissolution behavior. Moreover, differential scanning calorimetry (DSC) and X-ray powder diffraction analysis evidenced the transformation of the drug from its originally crystalline form into the amorphous one. Finally, the in vitro dissolution tests showed an increased dissolution rate of the drug from the granules (in particular steam granules) in comparison to pure drug and physical mixture. In conclusion, the results of this study suggested that the steam granulation technique could be considered an interesting alternative to traditional wet granulation to improve the dissolution rate of diclofenac.

Standardization and decay data of 237Np

This paper reports contributions from participants in the EUROMET project (No. 416) which was entitled "237Np research into problems relating to purification, characterization and standardization". Primary standardizations were made by the defined low solid angle, coincidence, 4pi alpha, 2pi alpha and liquid scintillation counting methods. Secondary standardizations were made with calibrated gamma-ray spectrometers. Absolute X-ray, gamma-ray and alpha-particle emission probabilities were also determined. The results for the successful conclusion of both primary and secondary standardization are presented together with the values for alpha-particle and gamma-ray emission probabilities determined in this exercise. Several significant inconsistencies remain with the gamma-ray emission probabilities, and these are highlighted.

Traumatic head injury in the anticoagulated elderly patient: a lethal combination

Warfarin is the most common oral anticoagulant used for chronic anticoagulation therapy. Even without any antecedent trauma overanticoagulation can result in intracranial hemorrhage. The triad of anticoagulation with warfarin, age greater than 65 years, and traumatic head injury frequently produces a lethal brain hemorrhage. A retrospective review of more than 2000 patients admitted to the Trauma Service between September 1998 and May 2000 produced 278 patients with head injury and CT-documented intracranial hemorrhage. Of these patients 21 were admitted with an elevated prothrombin time (PT) due to anticoagulation with warfarin. Eighteen patients (86%) were above the age of 70. The most common indications for anticoagulation were atrial fibrillation (71%), deep venous thrombosis (19%), aortic valve replacement (9%), and ischemic cerebral infarcts (9%). Fourteen injuries were the result of a fall, one resulted from a gunshot wound, and one resulted from an assault. The remaining five patients were excluded as their history, workup, and evaluation by neurosurgery suggested a spontaneous bleed leading to fall rather than a fall causing a traumatic bleed. The average Glasgow Coma Score on admission was 11. The average PT and International Normalized Ratio (INR) on admission were 19.2 and 2.99 respectively. Eight of the 16 patients analyzed died. The risk of intracranial hemorrhage with relatively minor head injury is increased dramatically in the anticoagulated patient. A mortality rate of 50 per cent far exceeds the mortality rate in patients with similar head injuries who are not anticoagulated. In addition the risk/benefit equation of anticoagulation for the elderly is more complex and differs from that for younger patients. Perhaps more frequent and judicious monitoring of prothrombin time levels with lower therapeutic ranges (INR 1.5-2) is necessary.

Intrinsic inhibition of aldose reductase

The development of aldose reductase inhibitors for the treatment of diabetic complications, such as cataract and retinopathy, has been of intense interest in the pharmaceutical community for the last 20 years. To date, aldose reductase inhibitors have been synthetically developed from leads obtained from in vitro screening studies. Recently, we have observed that mammalian tissues contain intrinsic inhibitors of aldose reductase, which may be used as potential drugs for treating diabetic complications with potentially less side effects than synthetic aldose reductase inhibitors. Intrinsic inhibitor(s) of aldose reductase have been observed in the methanolic extracts from rat and human kidneys and bovine lenses that were subjected to a number of chromatographic techniques, including counter current chromatography, flash chromatography, gel filtration and high pressure liquid chromatography. This inhibition results from a direct interaction between the inhibitor and enzyme. The intrinsic inhibitor, present in the lipophilic fraction of human kidney and bovine lens extracts, can easily penetrate into the lens to inhibit sugar alcohol formation. Intraperitoneal injection of partially purified bovine lens extract inhibited lens polyol formation in young rats fed 50% galactose diet.

Synthesis of potential aldose reductase inhibitors based on minimal pharmacophore requirements

A series of 17 compounds were synthesized based on the premise that the minimal pharmacophore for aldose reductase inhibition requires the presence of both an aryl group and polar group connected by a linking structure. Three groups of compounds were synthesized, the first possessing an aniline-4-(2'-6'-methylbenzothiazole) or 2-aminobenzothiazole group as the aryl group, the second possessing a 2-naphthyl as the aryl group and the third possessing either a 4-(2-phenylthiazole) or 2-(5-2'-nitrophenylfuran) as the aryl group. In all three of these groups the carboxylate or its methyl ester are linked to the aryl group through various lengths of methylene carbons and amide or cinnamide groups. Optimal activity was observed when the carboxylic group was separated from the aryl group by a linking structure of five atoms in length. Both a double bond and an amide moiety are well tolerated in the linking structure.

High-performance liquid chromatographic method development and validation for the simultaneous quantitation of naproxen sodium and pseudoephedrine hydrochloride impurities

A reversed-phase high-performance liquid chromatographic procedure for the simultaneous determination of impurities associated with pseudoephedrine hydrochloride (PSEH) and naproxen sodium (NapNa) is developed and validated. The method is developed using a Waters Spherisorb cyano column (5 microm, 250 x 4.6 mm). An isocratic elution in a water-acetonitrile-methanol-triethylamine mixture (850:75:75:5) is adjusted to a pH of 3.7 +/- 0.02 with formic acid as the mobile phase. The UV detection was set at 260 nm, and the wavelength was switched to 235 nm before the elution of the last component, 2-ethyl-6-methoxy-naphthalene (EMN). The method is shown to be linear at a concentration range of 0.24 to 1.92 microg/mL for benzaldehyde, benzoic acid, and 2-(methylamino)-propiophenone hydrochloride, which are known impurities of PSEH. The NapNa impurities, 2-(6'-hydroxy-2'-naphthyl) propionic acid, 2-hydroxy-6-methoxy-naphthalene, 1-(6'-methoxy-2'-naphthyl) ethanol, 2-acetyl-6-methoxy-naphthalene, and EMN are also demonstrated to be linear at a concentration range of 0.44 to 3.52 microg/mL. Under the chromatographic conditions of the method, all impurities are resolved from the active components.

Estimation of left ventricular operating stiffness from Doppler early filling deceleration time in humans

Shortened early transmitral deceleration times (E(DT)) have been qualitatively associated with increased filling pressure and reduced survival in patients with cardiac disease and increased left ventricular operating stiffness (K(LV)). An equation relating K(LV) quantitatively to E(DT) has previously been described in a canine model but not in humans. During several varying hemodynamic conditions, we studied 18 patients undergoing open-heart surgery. Transesophageal echocardiographic two-dimensional volumes and Doppler flows were combined with high-fidelity left atrial (LA) and left ventricular (LV) pressures to determine K(LV). From digitized Doppler recordings, E(DT) was measured and compared against changes in LV and LA diastolic volumes and pressures. E(DT) (180 +/- 39 ms) was inversely associated with LV end-diastolic pressures (r = -0.56, P = 0.004) and net atrioventricular stiffness (r = -0.55, P = 0.006) but had its strongest association with K(LV) (r = -0.81, P < 0.001). K(LV) was predicted assuming a nonrestrictive orifice (K(nonrest)) from E(DT) as K(nonrest) = (0.07/E(DT))(2) with K(LV) = 1.01 K(nonrest) - 0.02; r = 0.86, P < 0.001, DeltaK (K(nonrest) - K(LV)) = 0.02 +/- 0.06 mm Hg/ml. In adults with cardiac disease, E(DT) provides an accurate estimate of LV operating stiffness and supports its application as a practical noninvasive index in the evaluation of diastolic function.

Expressed sequence tags for the chicken genome from a normalized 10-day-old White Leghorn whole embryo cDNA library: 1. DNA sequence characterization and linkage analysis

Expressed sequence tags (ESTs) provide a rapid and reliable method for gene discovery as well as a resource for the large-scale analysis of gene expression of known and unknown genes. Here we describe a normalized cDNA library developed from a 10-day-old White Leghorn chicken whole embryo. The utility of the library was evaluated by partial sequencing of 99 randomly selected insert-containing clones and the analysis of EST-targeted genomic regions for single nucleotide polymorphisms (SNPs) in the East Lansing chicken reference DNA mapping panel. Using stringent match criteria of percent identity of 80 or higher across a length of 50 or more bases, 46 ESTs matched database sequences including previously reported Gallus gallus genes. Thirty-seven of the 50 primer pairs developed from 50 unique ESTs amplified a single fragment. The size of the 37 amplicons ranged from 276 to 693 bp for a total of 17,508 and an average of 473. About 70% of the SNPs detected were either G-->A or C-->T transition. The number of SNPs detected within the amplicons from EST-targeted genomic regions ranged from 0 to 4 for a total of 65 and a frequency of about 1 every 470 bases. About 35% of the amplicons contained only 1 SNP, while 19% had 4 SNPs. Using the SNPs that were informative in the East Lansing reference panel, 17 ESTs were mapped on the East Lansing chicken genetic map. The ESTs described, as well as the nucleotide variants identified within the EST-targeted genomic regions, represent significant resources for genome analysis in the chicken.

Comparison of new Doppler echocardiographic methods to differentiate constrictive pericardial heart disease and restrictive cardiomyopathy

This study assesses how the newer modalities of tissue Doppler echocardiography and color M-mode flow propagation compare with respiratory variation of Doppler flow in distinguishing between constrictive pericarditis and restrictive cardiomyopathy. We studied 30 patients referred for further evaluation of diastolic function who had a diagnosis of constrictive pericarditis or restrictive cardiomyopathy established by diagnostic tests, including clinical assessment, magnetic resonance imaging, cardiac catheterization, endomyocardial biopsy, and surgical findings. Nineteen patients had constrictive pericarditis and 11 had restrictive cardiomyopathy. We performed 2-dimensional transesophageal echocardiography combined with pulsed-wave Doppler of the pulmonary veins and mitral inflow with respiratory monitoring, tissue Doppler echocardiography of the lateral mitral annulus, and color M-mode flow propagation of left ventricular filling. Respiratory variation of the mitral inflow peak early (peak E) velocity of > or =10% predicted constrictive pericarditis with 84% sensitivity and 91% specificity and variation in the pulmonary venous peak diastolic (peak D) flow velocity of > or =18% distinguished constriction with 79% sensitivity and 91% specificity. Using tissue Doppler echocardiography, a peak early velocity of longitudinal expansion (peak Ea) of > or =8.0 cm/s differentiated patients with constriction from restriction with 89% sensitivity and 100% specificity. A slope of > or =100 cm/s for the first aliasing contour in color M-mode flow propagation predicted patients with constriction with 74% sensitivity and 91% specificity. Thus, the newer methods of tissue Doppler echocardiography and color M-mode flow propagation are equivalent and complimentary with Doppler respiratory variation in distinguishing between constrictive pericarditis and restrictive cardiomyopathy. The additive role of the new methods needs to be established in difficult cases of constrictive pericarditis where respiratory variation may be absent or decreased.

Percolation thresholds in ultrasound compacted tablets

Twenty matrix systems with different KCl content (as drug model, from 10 to 90% w/w) and Eudragit RS-PM (as inert excipient) were prepared using an ultrasound-assisted press and a traditional eccentric machine. The release behavior from both types of matrices was examined; the kinetic parameters for the release (intrinsic dissolution) and the technological properties of the final tablets (total porosity) were used to estimate the percolation threshold for the drug model and the excipient in both systems. For the systems compacted by ultrasound (US) the estimated value for the excipient percolation threshold ranges from 13.4 to 20.2% v/v (lower than that found for traditional tablets), that agrees with a continuum percolation model suggesting the presence of a continuum phase inside the tablet. This depends on a thermoplastic deformation of Eudragit RS-PM under ultrasound, that destroyed the particulate system of the excipient and transform it into a continuum medium. The percolation threshold for KCl ranged from 58.6 to 61.0% v/v for US and from 26.7 to 42.2% v/v for the traditional tablets. The higher value for ultrasound compacted tablets can be explained by the difficulty of KCl to outcome from a matrix containing insoluble phase that surrounds KCl crystals.

Scale-up of the preparation process of solid lipid nanospheres. Part I

An apparatus was designed to prepare solid lipid nanospheres (SLN), potential colloidal therapeutic system obtained by dispersing a warm oil-in-water (o/w) microemulsion in cold water. The apparatus, consisting mainly of a thermostated aluminium chamber and a pneumatic piston, permitted to disperse through a needle up to 100 ml of warm microemulsion and to vary the temperature, the dispersing rate and the drop size of the warm o/w microemulsion. Experimental design was applied to study the effect of four experimental factors, such as chamber temperature, piston pressure, needle gauge and volume of dispersing water, on average diameter and polydispersity index of SLN and on dispersing time of microemulsion (the time required for the microemulsion to drip completely from the apparatus). The results showed that temperature and pressure play the most important roles depending on the needle gauge used. In particular, the smallest SLN were obtained using high temperature and pressure values and a small needle gauge.

Generation of hybrid elloramycin analogs by combinatorial biosynthesis using genes from anthracycline-type and macrolide biosynthetic pathways

Elloramycin and oleandomycin are two polyketide compounds produced by Streptomyces olivaceus Tü2353 and Streptomyces antibioticus ATCC11891, respectively. Elloramycin is an anthracycline-like antitumor drug and oleandomycin a macrolide antibiotic. Expression in S. albus of a cosmid (cos16F4) containing part of the elloramycin biosynthetic gene cluster produced the elloramycin non-glycosylated intermediate 8-demethyl-tetracenomycin C. Several plasmid constructs harboring different gene combinations of L-oleandrose (neutral 2,6-dideoxyhexose attached to the macrolide antibiotic oleandomycin) biosynthetic genes of S. antibioticus that direct the biosynthesis of L-olivose, L-oleandrose and L-rhamnose were coexpressed with cos16F4 in S. albus. Three new hybrid elloramycin analogs were produced by these recombinant strains through combinatorial biosynthesis, containing elloramycinone or 12a-demethyl-elloramycinone (= 8-demethyl-tetracenomycin C) as aglycone moiety encoded by S. olivaceus genes and different sugar moieties, coded by the S. antibioticus genes. Among them is L-olivose, which is here described for the first time as a sugar moiety of a natural product.

Species differences in the efficacy of compounds at the nociceptin receptor (ORL1)

Recent studies have identified compounds with reduced efficacy relative to nociceptin/orphanin FQ at the opioid-like receptor ORL1. Utilizing stimulation of [(35)S]GTPgammaS binding as in vitro assays, it was determined that both [Phe(1)psi(CH(2)-NH)Gly(2)]N/OFQ(1-13)NH(2) and the hexapeptide Ac-RYYRIK-NH(2) act as partial agonists in CHO cells transfected with either human or mouse ORL1. Maximal activity for both [Phe(1)psi(CH(2)-NH)Gly(2)]N/OFQ(1-13)NH(2) and Ac-RYYRIK-NH(2) was significantly greater in cells transfected with the human receptor (90% and 73% in a high expressing clone, 76% and 68% in low expressing clone) rather than the mouse receptor (37.5 and 33%), regardless of receptor number in individual clones. In vitro studies in cells transfected with exaggerated receptor numbers can lead to unreliable estimates of agonist and antagonist activity, however, these studies suggest that animal experiments on the activity of novel compounds may not always be better predictors of the ultimate activity in humans.

The midvastus surgical approach in total knee arthroplasty

We report a study of 2 surgical approaches to the knee in 42 consecutive patients undergoing a total arthroplasty. They were divided into 2 groups. In Group 1 (n=17) the knee was exposed through classic medial parapatellar arthrotomy and in Group 2 (n=25) the knee was approached through the fibers of the medial vastus. Preoperative assessment did not reveal any statistical differences between the groups, and blood loss, operation time, biochemistry values and radiographic evaluation were also similar. However, a higher number of lateral releases, a loss of knee extension and a reduced range of motion were significantly associated with classical parapatellar arthrotomy. As the number of operative or postoperative complications was not increased, we recommend the mid-vastus approach for total knee arthroplasty.

Identification and expression of genes involved in biosynthesis of L-oleandrose and its intermediate L-olivose in the oleandomycin producer Streptomyces antibioticus

A 9.8-kb DNA region from the oleandomycin gene cluster in Streptomyces antibioticus was cloned. Sequence analysis revealed the presence of 8 open reading frames encoding different enzyme activities involved in the biosynthesis of one of the two 2, 6-deoxysugars attached to the oleandomycin aglycone: L-oleandrose (the oleW, oleV, oleL, and oleU genes) and D-desosamine (the oleNI and oleT genes), or of both (the oleS and oleE genes). A Streptomyces albus strain harboring the oleG2 glycosyltransferase gene integrated into the chromosome was constructed. This strain was transformed with two different plasmid constructs (pOLV and pOLE) containing a set of genes proposed to be required for the biosynthesis of dTDP-L-olivose and dTDP-L-oleandrose, respectively. Incubation of these recombinant strains with the erythromycin aglycon (erythronolide B) gave rise to two new glycosylated compounds, identified as L-3-O-olivosyl- and L-3-O-oleandrosyl-erythronolide B, indicating that pOLV and pOLE encode all enzyme activities required for the biosynthesis of these two 2,6-dideoxysugars. A pathway is proposed for the biosynthesis of these two deoxysugars in S. antibioticus.

Antinociceptive/anti-edema effects of liposomal morphine during acute inflammation of the rat paw

We evaluated the anti-edema/antinociceptive effects of subcutaneous free and liposomal morphine in rats with carrageenan-induced inflammation of the paw. We assessed antinociception by the paw pressure test and edema by plethysmography. Unilamellar liposomes (150-200 nm) with 0.3% morphine hydrochloride were used; encapsulation significantly reduced the rate for release of morphine in vitro. During inflammation, the antinociceptive potency of free, but not liposomal morphine increased 2.5 times; moreover, duration of the effects was prolonged by encapsulation (p < 0.001). The anti-edema effects of liposomal morphine were more pronounced (p < 0. 001) and of longer duration (p < 0.05). All the effects were reversed by naloxone. The results show that morphine encapsulation enhances the anti-edema effects and prolongs antinociception.

Iniencephaly: prenatal diagnosis and management

Iniencephaly is a rare malformation characterized by the triad of occipital bone defect, cervical dysraphism and fixed retroflexion of the fetal head. Because of its almost invariable lethal prognosis, termination of pregnancy is commonplace when this condition is diagnosed before viability. In this report we describe eight cases of iniencephaly prenatally diagnosed by ultrasound between 18 and 28 weeks of gestation and discuss the subsequent obstetric management in a country where elective abortion is illegal. Prenatal karyotyping was performed in seven cases, revealing a normal complement in all fetuses. One pregnancy miscarried at 24 weeks. Uneventful vaginal delivery was accomplished in six of the remaining seven cases, one delivered spontaneously at 29 weeks and five were induced between 28-32 weeks due to increasing polyhydramnios. In the remaining case the pregnancy progressed to 35 weeks, at which time spontaneous labour began and an emergency Caesarean section was performed because of malpresentation. There were no survivors in this series. We conclude that, in countries were elective abortion is not allowed, women carrying an iniencephalic fetus may benefit from preterm induction of labour in order to avoid labour dystocia, maternal trauma during delivery and the risks of a Caesarean section.

Development and characterization of expressed sequence tags for the turkey (Meleagris gallopavo) genome and comparative sequence analysis with other birds

Twenty-one randomly selected clones from a turkey (Meleagris gallopavo) pituitary complementary DNA (cDNA) library were sequenced to develop expressed sequence tags (ESTs) for this economically important avian species whose genome is among the least understood. Primers specific for the ESTs were used to produce amplicons from the genomic DNA of turkey, chicken (Gallus gallus), guinea fowl (Numidia meleagris), pigeon (Columba domestica), and quail (Corturnix japonica). The amplicons were sequenced and analyzed for sequence variation within- and similarity among-species and with GenBank database sequences. The proportion of shared bases between the turkey sequence and the consensus sequence from each of the other species ranged from 72% to 93% between turkey and pigeon and quail and between turkey and chicken, respectively. The total number of single nucleotide polymorphisms (SNPs) observed ranged from 3 in quail to 18 in chicken out of 4898 and 5265 bases analyzed, respectively. The most frequent nucleotide variation observed was a C-->T transition. Linkage analysis of one such SNP in the backcross progeny of the East Lansing reference DNA panel, localized TUS0005, the chicken sequence derived from primers specific for turkey TUT2E EST, to chromosome 4. The ESTs reported, as well as the SNPs may provide a useful resource for ongoing efforts to develop high utility genome maps for the turkey and chicken. The primers described can also be used as a tool in future investigations directed at further understanding the biology of the guinea fowl, pigeon and quail and their relatedness to the turkey.