Introduction: Renal vascular hypertension (RVH) accounts for 1–5% of the total population of pati... more Introduction: Renal vascular hypertension (RVH) accounts for 1–5% of the total population of patients with high blood pressure. In addition, the prevalence between patients with coronary and peripheral vascular disease usually is greater to 40%. Several noninvasive methods for diagnosis have been used in hypertensive patients with a suspicion of renal arteries stenosis, such as color Doppler ultrasound. The incorporation of echo enhancers (EE) to the echographic technique has had a significant impact for the yield of the study. Objective: To analyze the feasibility of total visualization of main renal artery with and without EE. To determine the sensitivity and diagnostic specificity of the conventional color Doppler parameters for the diagnosis of RVH: renal peak systolic velocity (RePSV), renal aortic ratio (RAR): RePSV/peak systolic velocity at the abdominal aorta (AoPSV), with and without EE. A new index of velocities was also proposed: the renal-hiliar index (ReHi-Index): RePSV/renal hilum peak systolic velocity (ReHiPSV), and was compared with conventional parameters in terms of sensitivity and specificity, using angiography as the gold standard method. Materials and Methods: 77 patients were included (45 males, 32 females, mean age 54 years) between July 1998 and April 2003. Echo-Doppler analysis was made with and without EE, comparing the feasibility of visualization of the renal arteries in all their passage: proximal, medium, and distal. Three different echo machines were used: Ving Med CFM 800 (2,5 MHz and 3,5 MHz transducer), Toshiba SSH 140-A (2,5 MHz and 3,75 MHz transducer) and Hewlett Packard Image Point HX (2,5 MHz and 4,0 MHz transducer). An EE composed of 999 mg of galactose and 1 mgof palmitic acid by each gram of grains was used with 300 mg/mL concentration. The direct parameters measured in the main renal artery were the following: (1) RePSV: as the highest Doppler velocity measured in systole in the main renal artery. (2) RAR: as the rate between renal peak systolic velocity, RePSV, divided by aortic peak systolic velocity, AoPSV, measured at the abdominal aorta. (3) ReHi Index: the rate between RePSV and renal hilum peak systolic velocity, ReHiPSV, measured at the hilum in its extrarenal section. Stenosis was considered significant when RePSV > 200 cm/s, RAR > 3.5 and new renal-hiliar Index >2.7. Renal angiography was performed in 16 patients with echographic diagnosis of renal artery stenosis. Statistical analyses included specificity, sensibility, and relative risk calculations on the three mentioned direct parameters. The Mantel-Haenszel chisquare test was applied to analyze statistically significant differences between the discrete parameters. Results: 77 patients were examined with conventional color echo Doppler technique with and without EE. All 151 of 151 the renal arteries segments, proximal, medium and distal, were observed with EE, (100% feasibility) and 137 of 151 without EE (91% feasibility) (p 60%), 3 with moderate obstruction (40–59%), 10 normal, 2 occluded, and one absent.The diagnostic accuracy of the direct parameters for the diagnosis of severe renal stenosis was as follows: (1) RePSV > 200 cm/s; 94% sensibility, 77% specificity, RR 9.17 (p 3.5: 69% sensibility, 100% specificity, RR 3.6 (p 2.7: 94% sensibility, 92% specificity, RR 12.24 (p< 0.001). The values of urea and creatinine in blood before and after the intravenous administration of EE were similar (p<0.72), showing EE as a well-tolerated product. Conclusions: (1) The visualization feasibility of renal arteries improved significantly with the EE use, increasing from 91% to 100% (p 200 cm/s and RAR > 3.5 (p< 0.0001). (3) EE showed an excellent security profile in terms of renal tolerance, also allowing its use in patients with deterioration of the renal function.
Saccharin and cyclamates have been proved to cause organic damage. This work attempt to describe ... more Saccharin and cyclamates have been proved to cause organic damage. This work attempt to describe drug-induced changes brought about by drugs in 1/1000 saccharin and cyclamate-fed rats for 90 days. The ultrastructural findings show: microvilli hypertrophy; membranous mitochondrial increase in absorptive cells; and secretion changes in calciform cells. Such changes are cell-response phenomena to interference or mutagenic action on nuclear DNA or on cytoplasmatic metabolism.
The aim of the present paper is to show lead toxicity and cell deposition of concentrations lower... more The aim of the present paper is to show lead toxicity and cell deposition of concentrations lower than those regarded as toxic on an experimental model with rats C3Hs., forty five grams-rats were used. A standard diet was administered together with water ad-libitium, containing very low doses of lead acetate which was constantly administered and at fixed periods. Light and electron microscopy were used to study the liver and the spleen. These organs are considered to harbour a great amount of constant macrophages with phagocytic function. The findings showed lesions and lead deposits which confirmed the causative agent as well as its toxic contaminating action.
The present study evaluated the effect of sodium saccharin on mouse tracheal epithelium, in relat... more The present study evaluated the effect of sodium saccharin on mouse tracheal epithelium, in relation to its possible structural alterations. Mice of the C3H strain were fed with standard pellets supplemented with sodium saccharin for 180 days. At that time the mice were sacrificed and their trachea were processed for transmission electronic microscopy. We demonstrated that sodium saccharin produces alterations in cellular surface cilia, with cytoplasmic excrescences and ciliary malformations. These results suggest that sodium saccharin is not an innocuous sweetener and that it may cause structural alterations in epithelial tissues.
In order to grow, solid tumors need to develop new blood vessels. Neoplastic cells secrete growth... more In order to grow, solid tumors need to develop new blood vessels. Neoplastic cells secrete growth factors that stimulate angiogenesis and tumor growth. Since Carrageenan acts as in vitro blocking agent which interferes with growth factor-receptor binding, we tested its action in vivo in order to analyze its growth inhibition capability in an experimental murine fibrosarcoma model. Indomethacin was used as a non-steroidal anti-inflammatory agent to neutralize the inflammatory action of Carrageenan. A murine fibrosarcoma was induced with methylcholanthrene in Balb/c mice and maintained by serial passage of tumor cells in mice of the same strain. Tumor volume was evaluated measuring two dimensions and applying the formula V = 0.4 x d2 x D. The mice with tumors were separated into groups; one of them was used as control and the other ones were treated with Indomethacin, Carrageenan and Carrageenan-Indomethacin. Tumor volume was compared between groups using the Student t Test. We demons...
Sodium saccharin has found to be a tumoral promoter in the rat's bladder epithelium, property... more Sodium saccharin has found to be a tumoral promoter in the rat's bladder epithelium, property not demonstrated in humans. Nevertheless, at present there's no references on the possible alterations produced by sodium saccharin in the epithelium of the mice colon. In this work we describe the alterations produced by low doses of sodium saccharin in the epithelium of the mice colon. The changer produced by sodium saccharin consist in pleomorphic microvill with variations of form, length diameter and curvature and demonstrate by transmission electron microscopy.
SUMMARY Introduction: Growth Factors (GF) are important subs- tances involved in the development ... more SUMMARY Introduction: Growth Factors (GF) are important subs- tances involved in the development of tumors. GF blockade is an attractive strategy as coadjuvant therapy in neoplasia treatment. Carrageenan acts by blocking GF and may influence mast cells, having a controversial role in tumour growth. We tried to analyze the effect of carrageenan and indomethacin in the development of a murine
Introduction: Renal vascular hypertension (RVH) accounts for 1–5% of the total population of pati... more Introduction: Renal vascular hypertension (RVH) accounts for 1–5% of the total population of patients with high blood pressure. In addition, the prevalence between patients with coronary and peripheral vascular disease usually is greater to 40%. Several noninvasive methods for diagnosis have been used in hypertensive patients with a suspicion of renal arteries stenosis, such as color Doppler ultrasound. The incorporation of echo enhancers (EE) to the echographic technique has had a significant impact for the yield of the study. Objective: To analyze the feasibility of total visualization of main renal artery with and without EE. To determine the sensitivity and diagnostic specificity of the conventional color Doppler parameters for the diagnosis of RVH: renal peak systolic velocity (RePSV), renal aortic ratio (RAR): RePSV/peak systolic velocity at the abdominal aorta (AoPSV), with and without EE. A new index of velocities was also proposed: the renal-hiliar index (ReHi-Index): RePSV/renal hilum peak systolic velocity (ReHiPSV), and was compared with conventional parameters in terms of sensitivity and specificity, using angiography as the gold standard method. Materials and Methods: 77 patients were included (45 males, 32 females, mean age 54 years) between July 1998 and April 2003. Echo-Doppler analysis was made with and without EE, comparing the feasibility of visualization of the renal arteries in all their passage: proximal, medium, and distal. Three different echo machines were used: Ving Med CFM 800 (2,5 MHz and 3,5 MHz transducer), Toshiba SSH 140-A (2,5 MHz and 3,75 MHz transducer) and Hewlett Packard Image Point HX (2,5 MHz and 4,0 MHz transducer). An EE composed of 999 mg of galactose and 1 mgof palmitic acid by each gram of grains was used with 300 mg/mL concentration. The direct parameters measured in the main renal artery were the following: (1) RePSV: as the highest Doppler velocity measured in systole in the main renal artery. (2) RAR: as the rate between renal peak systolic velocity, RePSV, divided by aortic peak systolic velocity, AoPSV, measured at the abdominal aorta. (3) ReHi Index: the rate between RePSV and renal hilum peak systolic velocity, ReHiPSV, measured at the hilum in its extrarenal section. Stenosis was considered significant when RePSV > 200 cm/s, RAR > 3.5 and new renal-hiliar Index >2.7. Renal angiography was performed in 16 patients with echographic diagnosis of renal artery stenosis. Statistical analyses included specificity, sensibility, and relative risk calculations on the three mentioned direct parameters. The Mantel-Haenszel chisquare test was applied to analyze statistically significant differences between the discrete parameters. Results: 77 patients were examined with conventional color echo Doppler technique with and without EE. All 151 of 151 the renal arteries segments, proximal, medium and distal, were observed with EE, (100% feasibility) and 137 of 151 without EE (91% feasibility) (p 60%), 3 with moderate obstruction (40–59%), 10 normal, 2 occluded, and one absent.The diagnostic accuracy of the direct parameters for the diagnosis of severe renal stenosis was as follows: (1) RePSV > 200 cm/s; 94% sensibility, 77% specificity, RR 9.17 (p 3.5: 69% sensibility, 100% specificity, RR 3.6 (p 2.7: 94% sensibility, 92% specificity, RR 12.24 (p< 0.001). The values of urea and creatinine in blood before and after the intravenous administration of EE were similar (p<0.72), showing EE as a well-tolerated product. Conclusions: (1) The visualization feasibility of renal arteries improved significantly with the EE use, increasing from 91% to 100% (p 200 cm/s and RAR > 3.5 (p< 0.0001). (3) EE showed an excellent security profile in terms of renal tolerance, also allowing its use in patients with deterioration of the renal function.
Saccharin and cyclamates have been proved to cause organic damage. This work attempt to describe ... more Saccharin and cyclamates have been proved to cause organic damage. This work attempt to describe drug-induced changes brought about by drugs in 1/1000 saccharin and cyclamate-fed rats for 90 days. The ultrastructural findings show: microvilli hypertrophy; membranous mitochondrial increase in absorptive cells; and secretion changes in calciform cells. Such changes are cell-response phenomena to interference or mutagenic action on nuclear DNA or on cytoplasmatic metabolism.
The aim of the present paper is to show lead toxicity and cell deposition of concentrations lower... more The aim of the present paper is to show lead toxicity and cell deposition of concentrations lower than those regarded as toxic on an experimental model with rats C3Hs., forty five grams-rats were used. A standard diet was administered together with water ad-libitium, containing very low doses of lead acetate which was constantly administered and at fixed periods. Light and electron microscopy were used to study the liver and the spleen. These organs are considered to harbour a great amount of constant macrophages with phagocytic function. The findings showed lesions and lead deposits which confirmed the causative agent as well as its toxic contaminating action.
The present study evaluated the effect of sodium saccharin on mouse tracheal epithelium, in relat... more The present study evaluated the effect of sodium saccharin on mouse tracheal epithelium, in relation to its possible structural alterations. Mice of the C3H strain were fed with standard pellets supplemented with sodium saccharin for 180 days. At that time the mice were sacrificed and their trachea were processed for transmission electronic microscopy. We demonstrated that sodium saccharin produces alterations in cellular surface cilia, with cytoplasmic excrescences and ciliary malformations. These results suggest that sodium saccharin is not an innocuous sweetener and that it may cause structural alterations in epithelial tissues.
In order to grow, solid tumors need to develop new blood vessels. Neoplastic cells secrete growth... more In order to grow, solid tumors need to develop new blood vessels. Neoplastic cells secrete growth factors that stimulate angiogenesis and tumor growth. Since Carrageenan acts as in vitro blocking agent which interferes with growth factor-receptor binding, we tested its action in vivo in order to analyze its growth inhibition capability in an experimental murine fibrosarcoma model. Indomethacin was used as a non-steroidal anti-inflammatory agent to neutralize the inflammatory action of Carrageenan. A murine fibrosarcoma was induced with methylcholanthrene in Balb/c mice and maintained by serial passage of tumor cells in mice of the same strain. Tumor volume was evaluated measuring two dimensions and applying the formula V = 0.4 x d2 x D. The mice with tumors were separated into groups; one of them was used as control and the other ones were treated with Indomethacin, Carrageenan and Carrageenan-Indomethacin. Tumor volume was compared between groups using the Student t Test. We demons...
Sodium saccharin has found to be a tumoral promoter in the rat's bladder epithelium, property... more Sodium saccharin has found to be a tumoral promoter in the rat's bladder epithelium, property not demonstrated in humans. Nevertheless, at present there's no references on the possible alterations produced by sodium saccharin in the epithelium of the mice colon. In this work we describe the alterations produced by low doses of sodium saccharin in the epithelium of the mice colon. The changer produced by sodium saccharin consist in pleomorphic microvill with variations of form, length diameter and curvature and demonstrate by transmission electron microscopy.
SUMMARY Introduction: Growth Factors (GF) are important subs- tances involved in the development ... more SUMMARY Introduction: Growth Factors (GF) are important subs- tances involved in the development of tumors. GF blockade is an attractive strategy as coadjuvant therapy in neoplasia treatment. Carrageenan acts by blocking GF and may influence mast cells, having a controversial role in tumour growth. We tried to analyze the effect of carrageenan and indomethacin in the development of a murine
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