Retraction Note: Study of liver toxicity and DNA damage due to exposure to the pesticide Mancozeb in an experimental animal model - A pilot model.

The article "Study of liver toxicity and DNA damage due to exposure to the pesticide Mancozeb in an experimental animal model - A pilot model", by N.D. Suarez Uribe, M.F. Pezzini, J. Dall'Agnol, N. Marroni, S. Benitez, D. Benedetti, J. Da Silva, C.T. Cerski, E. Dallegrave, S. Macedo, S.C.W.S.E.F. de Oliveira, D. Joveleviths, published in Eur Rev Med Pharmacol Sci 2023; 27 (13): 6374-6383-DOI: 10.26355/eurrev_202307_32997-PMID: 37458654 has been retracted by the Editor in Chief for the following reasons: After publication, concerns were raised by an unidentified reader who underlined some similarities between this publication and a previous publication published in the Journal of Clinical and Experimental Gastroenterology. After being informed, the authors claimed the previous journal published the article without consent, and, therefore, the authors promptly withdrew the previous publication. The retraction published by the other journal does not contain any information regarding the reason for withdrawal. As a matter of fact, the journal does not have any evidence about the authors' claim and still considers this research a duplicate publication. For the above-mentioned reasons, the Editor in Chief decided to withdraw the manuscript. This manuscript has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/32997.

Study of liver toxicity and DNA damage due to exposure to the pesticide Mancozeb in an experimental animal model - A pilot model.

OBJECTIVE: Mancozeb is one of the most widely used Ethylenebisdithiocarbamates fungicides in Brazil. A pilot experimental model was created to evaluate its potential hepatotoxic effect. MATERIALS AND METHODS: An experimental study was performed with 27 male Wistar rats (3 groups). The Control Group received a saline solution, while Intervention Groups I and II received 250 mg/kg and 500 mg/kg of Mancozeb respectively, once a week, for 12 weeks. Anthropometric measurements were carried out, and the marker of biological exposure in urine was dosed. Biochemical tests, evaluation micronucleus count, comet and oxidative stress markers assay, and histological assessment of the liver were also performed. RESULTS: The hepatotoxic effect of Mancozeb was confirmed by anthropometric measurements, genotoxicity, and oxidative stress. Statistically significant results were found when the exposed groups were compared to the control group. CONCLUSIONS: These results were supported by inflammatory infiltration and balloonization in the treated groups. The experimental model effectively demonstrated the deleterious effect of Mancozeb on the liver.

2016 Comprehensive Update of the Banff Working Group on Liver Allograft Pathology: Introduction of Antibody-Mediated Rejection.

The Banff Working Group on Liver Allograft Pathology reviewed and discussed literature evidence regarding antibody-mediated liver allograft rejection at the 11th (Paris, France, June 5-10, 2011), 12th (Comandatuba, Brazil, August 19-23, 2013), and 13th (Vancouver, British Columbia, Canada, October 5-10, 2015) meetings of the Banff Conference on Allograft Pathology. Discussion continued online. The primary goal was to introduce guidelines and consensus criteria for the diagnosis of liver allograft antibody-mediated rejection and provide a comprehensive update of all Banff Schema recommendations. Included are new recommendations for complement component 4d tissue staining and interpretation, staging liver allograft fibrosis, and findings related to immunosuppression minimization. In an effort to create a single reference document, previous unchanged criteria are also included.

Relationship between ischemia/reperfusion injury and the stimulus of fibrogenesis in an experimental model: comparison among different preservation solutions.

BACKGROUND AND AIMS: Orthotopic liver transplantation (OLT) has been the standard treatment for end-stage acute and chronic liver disease. Ischemia-reperfusion (I/R) injury is one of the major causes of poor graft function early after OLT, and adversely influencing graft and patient survivals. It is unknown whether I/R injury influences liver fibrogenesis. MATERIALS AND METHODS: Livers from 25 adult male Wistar rats were randomly assigned into 5 experimental groups according to the preservation solution: saline solution (SS); University of Wisconsin (UW) solution; Fructose 1, 6-biphosphate (FBP); S-Nitroso-N-Acetylcysteine (SNAC): or UW+SNAC (SNAC+UW). Aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactic dehydrogenase (LDH) were determined in preservation solution samples at 2, 4, and 6 hours. After 6 hours of cold ischemia, ex situ reperfusion was applied to the liver for 15 minutes. Serum AST, ALT, LDH, and renin levels were determined. Fresh liver slices were processed for histological studies, determination of thiobarbituric acid reactive substances, catalase, and glutathione, and expression of TGF-ß1 and angiotensin II AT1 receptor. RESULTS: AST was significantly lower during cold storage with UW than with the older media (P=.001); ALT was lower in the FBP group (P=.023) and LDH was lower in the FBP and SNAC groups (P=.007). After reperfusion, serum AST, ALT, LDH, and TBARS showed no significant differences among the groups. Catalase was significantly lower in the SS and FBP groups (P=.008 and P=.006, respectively). Compared with UW, glutathione concentrations were significantly higher in SS, FBP, and SNAC 200 (P=.004). Renin levels were significantly lower in the FBP group (P=.022). No histological signs of preservation injury were observed in the hepatic sample. No expressions were detected of TGF-ß1 or AT1 receptor. CONCLUSION: In this experimental model of early reperfusion injury, preservation changes related to higher levels of renin, which suggest its role in fibrogenesis. FBP was associated with lower renin levels than other solutions including UW.

Fructose 1-6 bisphosphate versus University of Wisconsin solution for rat liver preservation: does FBP prevent early mitochondrial injury?

BACKGROUND: Fructose 1,6-biphosphate (FBP) has been shown to exert therapeutic effects in models of ischemia-reperfusion in organs other than the liver. This study compared FBP and University of Wisconsin (UW) solution during cold storage and reperfusion, among mitochondria of adult male Wistar rat livers. METHODS: Adult male Wistar rats were assigned to two groups according to the preservation solution used; UW or FBP Aspartate transaminase (AST), alanine transferase (ALT); and lactic dehydrogenase (LDH) were measured in samples of the storage solution obtained at 2, 4 and 6 hours of preservation. After 6 hours of cold storage, we reperfused the liver, taking blood samples to measure AST, ALT, LDH, and throbarbituric acid reactive substances (TBARS). Hepatic fragments were processed for histologic analysis; for determinations of TBARS, catalase, and nitric oxide as well as for mitochondrial evaluation by infrared spectroscopy. RESULTS: During cold preservation, levels of AST and LDH in the storage solution were lower among the FBP group, but after reperfusion, serum levels of AST, ALT, and LDH were higher in this group, as was catalase activity. TBARS and nitric oxide were comparable between the groups. In the UW group there was a higher amide I/amide II ratio than in the FBP group, suggesting an abnormal protein structure of the mitochondrial membrane. No signs of preservation injury were observed in any liver biopsy, but sinusoidal congestion was present in livers preserved with FBP. CONCLUSION: FBP showed a protective effect for preservation during cold storage seeming to protect the mitochondrial membrane although it did not prevent reperfusion injury.

S-nitroso-N-acetylcysteine: a promising drug for early ischemia/reperfusion injury in rat liver.

BACKGROUND/AIMS: Ischemia-reperfusion (I/R) injury is among the major causes of poor graft function early after liver transplantation that adversely influences patient survival. A variety of mediators have been implicated in the pathogenesis of I/R vascular injury, including nitric oxide (NO). Because of the beneficial effects of NO during preconditioning and reperfusion, strategies to prevent or ameliorate I/R injury through the stimulation of hepatic NO production are an area of significant clinical interest. We evaluated the role of S-nitroso-N-acetylcysteine (SNAC) as an NO donor in the prevention of liver I/R injury in an animal model. METHODS: Adult male Wistar rats were randomly assigned to 3 experimental groups containing 5 animals each: the University of Wisconsin (UW) solution group; SNAC solution group; and SNAC-containing UW solution (SNAC+UW) group. Aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) were determined in samples of the cold storage solution at 2, 4, and 6 hours of preservation. After 6 hours of cold storage, We applied a 15-minute reperfusion period. Thereafter, the reperfusion was interrupted with blood samples obtained to measure AST, ALT, LDH, and thiobarbituric acid reactive substances (TBARS). Hepatic fragments were processed for histologic analysis, and to determine of TBARS, catalase, and glutathione levels. RESULTS: During cold preservation, AST and LDH were significantly lower among the SNAC than the UW group or the SNAC+UW group (P = .004 and P = .03, respectively). ALT was comparable among the groups (P = .3). After reperfusion, serum levels of AST, ALT, and LDH, as well as of hepatic TBARS and catalase showed no differences among the groups. Glutathione concentration was lower in the SNAC and SNAC+UW group (P < .001) compared with the UW group. We did not observe histologic signs of preservation injury. CONCLUSION: The SNAC solution showed a greater protective effect to preserve rat livers during cold storage, but it was comparable with UW.

Hepatic reperfusion in rats: a new model with portal arterialization in studying early ischemia-reperfusion injury.

Isolated liver perfusion has been used to evaluate the beneficial effects of several agents. In the present study, we developed a model using a recipient rat to reperfuse harvested livers in an ex situ, in vivo recirculating system. A total of 25 reperfusion procedures using adult male Wistar rats as donors and recipients were done. The preservation of the livers was performed with University of Wisconsin solution for 6 hours. Thereafter, the liver was reperfused with blood from another rat. We believe that the model presented herein offers an alternative method to evaluate early hepatocellular damage or hepatic microcirculation.

Sentinel lymph node identification and sampling in women with early breast cancer using 99m Tc labelled dextran 500 and patent blue V dye.

The status of the homolateral axillary lymph nodes is still the most important prognostic factor in early stage breast cancer. The information obtained from the pathological examination of the lymph nodes guides is of critical importance in the decision process regarding the use of postoperative adjuvant therapy. However, lymph node axillary dissection can be followed by significant locoregional morbidity. The sentinel lymph node (SLN) technique was developed as a means of avoiding the full exploration of the axilla and consists in the identification of the first lymph node in the lymphatic drainage system of the breast tumour in the homolateral axilla. It has been demonstrated that the status of the SLN is highly predictive for the presence or absence of tumour involvement in the remaining lymph nodes in the axilla. In this study we evaluated the SLN technique using both 99mTc labelled dextran 500 and patent blue V dye in relation to the classical lymph node resection a series of 56 women with early breast cancer who attended the Breast Unit of the Academic Hospital of the Federal University of Rio Grande do Sul, Brazil. To our knowledge this is the first report in the literature of the utilization of 99mTc dextran 500 for the SLN technique. As there are no similar commercially available dedicated radiopharmaceuticals labelled for use in lymphoscintigraphy studies, we report on an effective method to label dextran 500 with 99mTc which proved to be simple, inexpensive and yielded similar results for SLN identification compared with those given in the literature. The median age of the patients was 57 years (range 32-82 years). Seventeen patients were age 50 years or less, and 39 patients were older than 50 years. The median tumour size was 2.0 cm (range 0.8-7.0 cm). The mapping of the SLN was possible in all cases during the transoperative period by using a hand-guided gamma probe and a blue dye. A median of 2.0 (range 1-5) SLN were excised per patient. The median of axillary lymph nodes excised per patient was 21 (range 10-36). The calculated sensitivity and specificity of the method were 95.6% and 100%, respectively. The negative predictive value and overall accuracy were 97% and 98.2%, respectively. In conclusion, the SLN technique was feasible and produced similar positive results as previously reported in the literature.

[Experience in patients with suspected chronic liver disease and contraindication for percutaneous biopsy using modified Ross needle]. / Experiência em pacientes com suspeita de hepatopatia crônica e contra-indicação para biópsia hepática percutânea utilizando a agulha de Ross modificada.

PURPOSE: This work aimed at introducing the transjugular liver biopsy technique oriented by radiologic methods in our hospitals. This technique is indicated for obtaining histopathologic diagnosis in patients clinically and laboratory suspected of having chronic liver disease with contraindications to percutaneous liver biopsy. METHODS: Liver biopsy was obtained with a modified Ross needle through the right jugular vein and right hepatic vein under fluoroscopic control. RESULTS: Transjugular liver biopsy was attempted for 39 patients, liver tissue obtained en 32 and histopathologic diagnosis in 25 (64.1%). In 11 patients (28.2%) there was agreement between the diagnoses established before and after biopsy, however, in 14 patients (35.9%), there was disagreement. The yield of diagnosis was low when patients were suspected for cirrhosis. The procedure was well tolerated by the majority of patients. Nonetheless, 1 presented intra-abdominal bleeding and required immediate surgery to control retroperitoneal hemorrhage. CONCLUSIONS: Transjugular liver biopsy is useful for the histopathologic diagnosis of patients with chronic liver diseases whenever the percutaneous route is contraindicated. In this series we obtained histopathologic diagnosis for 64.1% of the subjects studied. Patients suspected of having cirrhosis had a low yield of histopathologic diagnosis (50%) when compared to subjects without clinical evidence for cirrhosis (78.9%). The technique is rather complex, and can cause serious complications. This, it should be performed in reference centers in radiology and hepatology.

Effects of chronic exposure to coal in wild rodents (Ctenomys torquatus) evaluated by multiple methods and tissues.

Rio Grande do Sul (RS) coal is low quality and typically obtained by strip mining. In a recent study concerning 2 years of biomonitoring in coal regions, we demonstrated the genotoxicity of coal and related products on blood cells of native rodents, from RS, Brazil. With the goal of studying the variations in the effects of RS coal on different tissues of the same rodent, we utilized, besides the single cell gel (SCG) and micronucleus (MN) assay on blood, histological analyses and SCG assay of bone marrow, spleen, kidney, liver and lung cells, and MN assay of bone marrow and spleen cells. In addition, to identify agents that can potentially influence the results, concentrations of several heavy metals were analyzed in livers and in soil, and the total concentration of hydrocarbons in the soil was determined. Rodents exposed to coal were captured at two different sites, Butiá and Candiota, in RS. Reference animals were obtained from Pelotas, where there is no coal mining. This report provides chemical and biological data from coal regions, indicating the possible association between Zn, Ni, Pb and hydrocarbons in the induction of DNA damage (e.g. single strand-breaks and alkali-labile sites) determined by the alkaline SCG assay in cells from Ctenomys torquatus. The results of the present SCG study indicate that coal and by-products not only induce DNA damage in blood cells, but also in other tissue cells, mainly liver, kidney and lung. Neither the MN assay nor histopathological observations showed significant differences; these analyses may be useful under circumstances where genotoxicity is higher. In conclusion we believe that the in vivo genotoxicity of coal can be biomonitored by the SCG assay, and our studies suggest that wild rodents, such as C. torquatus are useful for monitoring genotoxic damage by both methods, the SCG assay and the MN test.

Experiência em pacientes com suspeita de hepatopatia crônica e contra-indicaçäo para biópsia hepática percutânea utilizando a agulha de Ross modificada / Experience in patients with suspected chronic liver disease and contraindication for percutaneous biopsy using modified Ross needle

OBJETIVOS: O trabalho visou introduzir em nosso meio a técnica de biópsia hepática transjugular orientada por métodos radiológicos para a obtenção do diagnóstico histológico em pacientes clínica e laboratorialmente diagnosticados com hepatopatia crônica e com pelo menos uma das contra-indicações à biópsia hepática percutânea: coagulopatia, ascite maciça e anemia crônica acentuada com insuficiência renal crônica ou obesidade mórbida. MÉTODOS: Biópsia hepática aspirativa foi obtida com agulha de Ross modificada, através da punção da veia jugular interna com cateterização da veia hepática direita sob controle fluoroscópico. RESULTADOS: Trinta e nove pacientes foram estudados, obtendo-se tecido hepático em 32 (82 por cento ) sendo satisfatório para diagnóstico histológico em 25 (64,1 por cento ), com concordância entre o diagnóstico pré e pós-biópsia em 11 (28,2 por cento ) e discordância em 14 pacientes (35,9 por cento ). O procedimento foi bem tolerado pela maioria dos pacientes; contudo um paciente apresentou sangramento retroperitoneal, necessitando cirurgia imediata para controle da hemorragia. CONCLUSÕES: A biópsia hepática transjugular é um método diagnóstico útil para o estudo histopatológico na suspeita de hepatopatia crônica com contra-indicações a biópsia hepática percutânea. Em nossa série foi obtido diagnóstico histopatológico em 64,1 por cento dos indivíduos estudados. Pacientes com suspeita clínica de cirrose tiveram baixo diagnóstico histopatológico (50 por cento ) quando comparados com indivíduos sem essa suspeita (78,9 por cento ). O método é relativamente complexo, podendo apresentar complicações graves, e deve ser realizado em centros de excelência em radiologia e hepatologia.

Histopathological diagnosis of intra- and extrahepatic neonatal cholestasis.

The histopathology of the liver is fundamental for the differential diagnosis between intra- and extrahepatic causes of neonatal cholestasis. However, histopathological findings may overlap and there is disagreement among authors concerning those which could discriminate between intra- and extrahepatic cholestasis. Forty-six liver biopsies (35 wedge biopsies and 11 percutaneous biopsies) and one specimen from a postmortem examination, all from patients hospitalized for neonatal cholestasis in the Pediatrics Service of Hospital de Clínicas de Porto Alegre, were prospectively studied using a specially designed histopathological protocol. At least 4 of 5 different stains were used, and 46 hepatic histopathological variables related to the differential diagnosis of neonatal cholestasis were studied. The findings were scored for severity on a scale from 0 to 4. Sections which showed less than 3 portal spaces were excluded from the study. Sections were examined by a pathologist who was unaware of the final diagnosis of each case. Bile tract permeability was defined by scintigraphy of the bile ducts and operative cholangiography. The F test and discriminant analysis were used as statistical methods for the study of the hepatic histopathological variables. The chi-square method with Yates correction was used to relate the age of the patients on the date of the histopathological study to the discriminatory variables between intra- and extrahepatic cholestasis selected by the discriminant function test. The most valuable hepatic histopathological variables for the discrimination between intra- and extrahepatic cholestasis, in decreasing order of importance, were periportal ductal proliferation, portal ductal proliferation, portal expansion, cholestasis in neoductules, foci of myeloid metaplasia, and portal-portal bridges. The only variable which pointed to the diagnosis of intrahepatic cholestasis was myeloid metaplasia. Due to the small number of patients who were younger than 60 days on the date of the histopathological study (N = 6), no variable discriminated between intra- and extrahepatic cholestasis before the age of 2 months and all of them, except for the portal expansion, were discriminatory after this age. In infants with cholestasis, foci of myeloid metaplasia, whenever present in the liver biopsy, suggested intrahepatic cholestasis. Periportal ductal proliferation, portal ductal proliferation, portal expansion, cholestasis in neoductules, portal cholestasis and portal-portal bridges suggested extrahepatic obstructive cholestasis.

Histopathological diagnosis of intra-and extrahepatic neonatal cholestasis

The histopathology of the liver is fundamental for the differential diagnosis between intra- and extrahepatic causes of neonatal cholestasis. However, histopathological findings may overlap and there is disagreement among authors concerning those which could discriminate between intra- and extrahepatic cholestasis. Forty-six liver biopsies (35 wedge biopsies and 11 percutaneous biopsies) and one specimen from a postmortem examination, all from patients hospitalized for neonatal cholestasis in the Pediatrics Service of Hospital de Clínicas de Porto Alegre, were prospectively studied using a specially designed histopathological protocol. At least 4 of 5 different stains were used, and 46 hepatic histopathological variables related to the differential diagnosis of neonatal cholestasis were studied. The findings were scored for severity on a scale from 0 to 4. Sections which showed less than 3 spaces were excluded form the study. Sections were examined by a pathologist who was unaware of the final diagnosis of each case. Bile tract permeability was defined by scintigraphy of the bile ducts and operative cholangiography. The F test and discriminant analysis were used as statistical methods for the study of the hepatic histopathological variables. The chi-square method with Yates correction was used to relate the age of the patients on the date of the histopathological study to the discriminatory variables between intra- and extrahepatic cholestaasis selected by the discriminant function test. The most valuable hepatic histopathological variables for the discrimination between intra- and extrahepatic cholestasis, in decreasing order of importance, were periportal ductal proliferation, portal ductal proliferation, portal expansion, cholestasis in neoductules, foci of myeloid metaplasia, and portal-portal bridges. The only variable which pointed to the diagnosis of intrahepatic cholestasis was myeloid metaplasia. Due to the small number of patients who were younger than 60 days on the date of the histopathological study (N=6), no variable discriminated between intra- and extrahepatic cholestasis before the age of 2 months and all of them, except for the portal expansion, were discriminatory after this age. In infants with cholestasis, foci of myeloid metaplasia, whenever present in the liver biopsy, suggested intrahepatic cholstasis. Periportal ductal proliferation, portal ductal proliferation, portal expansion, cholestasis in neoductules...

[Polysplenia syndrome associated to neonatal hepatitis] / Síndrome de polisplenia associada à hepatite neonatal idiopática.

OBJECTIVE: To report the unusual association between neonatal hepatitis and polysplenia syndrome.METHODS: Clinical, biochemical, histopathological, surgical and image analysis methods were used.RESULTS: The 36 days old patient presented hyperbilirubinemia with increase of direct reacting bilirubin and high alkaline phosphatase. The physical examination evidenced jaundice and hepatomegaly. The chest X-ray showed situs inversus and dextrocardia. Abdominal ultrasonography presented an increase in liver volume, mainly at the right lobe. There were two cystic lesions at the liver with absence of intrahepatic biliary tract dilatation. Absence of splenomegaly. Biliary scintigraphy didn't show any excretion of radioisotope to the duodenum while transoperative cholangiography presented contrast medium flowing to the duodenum lumen. During laparotomy it was possible to observe polysplenia, abdominal aorta to the right of the lower vena cava, gallbladder at the left lobe of the liver, appendix on the left side of the abdomen and sigmoid colon on the right side. The hepatic wedge biopsy was compatible with idiopathic neonatal hepatitis.CONCLUSION: The finding of polysplenia syndrome in patients with neonatal cholestasis doesn't necessarily indicate the recurrent presence of extrahepatic biliary atresia.

Postangioplasty restenosis: a practical model in the porcine carotid artery

Transluminal coronary angioplasty is a routine therapeutic intervention in coronary heart disease. Despite the high rate of primary success, restenosis continues to be its major limitation. Porcine models have been considered to be the most adequate experimental models for studying restenosis. One limitation of porcine models is the need for radiological guidance and the expenses involved. The objective of the present study was to adapt an experimental model of angioplasty in the porcine carotid artery that does not require radiological equipment. Eight animals were used to develop the technique of balloon injury to the common carotid artery by dissection without radiological guidance. This technique was then employed in six other animals. Under anesthesia, the left common carotid artery was dissected and incised at the carotid sinus for insertion of an over-the-wire angioplasty balloon towards the aorta. Overstretch injury of the carotid artery was performed under direct visualization. After 30 days, the arteries were excised and pressure-fixated. Uninjured carotid arteries from 3 additional animals were used as controls. A decreased luminal area associated with intimal hyperplasia and medial reaction was observed in all injured arteries. Immunohistochemistry identified the intimal hyperplastic cells as smooth muscle cells. Computerized morphometry of the ballooned segments revealed the following mean areas: lumen 2.12mm2 (+ 1.09), intima 0.22mm2 (+ 0.08), media 3.47mm2 (+ 0.67), and adventitia 1.11mm2 (+ 0.34). Our experimental model of porcine carotid angioplasty without radiological guidance induced a vascular wall reaction and permitted the quantification of this response. This porcine model may facilitate the study of vascular injury and its response to pharmacological interventions.

[Neonatal cholestasis: the delay in referring patients for differential diagnosis]. / Colestase neonatal - atraso no encaminhamento de crianças para diagnóstico diferencial.

OBJECTIVE: An efficient treatment of extrahepatic biliary atresia demands that the diagnostic differentiation between intra- and extrahepatic neonatal cholestasis be performed by the eighth week of life. This study aimed at evaluate the age of the patients admitted to a general hospital for differential diagnosis of cholestatic jaundice. METHODS: Forty nine children from the Pediatric Service at Hospital de Clínicas, in Porto Alegre, have been studied between 1984 and 1991, according to the protocol for diagnostic elucidation followed by this hospital, which includes biliary tract scintigraphy with Tc-99m DISIDA and, depending on its results, an wedge or percutaneous liver biopsy. The ages of the children have been compared on the occasion of the procedures. Twenty six cases have been studied retrospectively and 23, prospectively. RESULTS: Both the patients with intrahepatic and extrahepatic cholestasis underwent scintigraphy, on average at over eight weeks (age 77.94 +/- 42.98 days) and the histopathological study of the liver was performed approximately two weeks after scintigraphy. Only six patients (12.8% of the 47 cases) underwent the liver biopsy before the first eighth week of life. CONCLUSIONS: A delay was observed in referring patients for differential diagnosis of neonatal cholestasis and the performance of tests. The need of hospitalization in order to conduct these procedures delays even further this diagnosis, which should be concluded by the eighth week of life.

Postangioplasty restenosis: a practical model in the porcine carotid artery.

Transluminal coronary angioplasty is a routine therapeutic intervention in coronary heart disease. Despite the high rate of primary success, restenosis continues to be its major limitation. Porcine models have been considered to be the most adequate experimental models for studying restenosis. One limitation of porcine models is the need for radiological guidance and the expenses involved. The objective of the present study was to adapt an experimental model of angioplasty in the porcine carotid artery that does not require radiological equipment. Eight animals were used to develop the technique of balloon injury to the common carotid artery by dissection without radiological guidance. This technique was then employed in six other animals. Under anesthesia, the left common carotid artery was dissected and incised at the carotid sinus for insertion of an over-the-wire angioplasty balloon towards the aorta. Overstretch injury of the carotid artery was performed under direct visualization. After 30 days, the arteries were excised and pressure-fixated. Uninjured carotid arteries from 3 additional animals were used as controls. A decreased luminal area associated with intimal hyperplasia and medial reaction was observed in all injured arteries. Immunohistochemistry identified the intimal hyperplastic cells as smooth muscle cells. Computerized morphometry of the ballooned segments revealed the following mean areas: lumen 2.12 mm2 (+/- 1.09), intima 0.22 mm2 (+/- 0.08), media 3.47 mm2 (+/- 0.67), and adventitia 1.11 mm2 (+/- 0.34). Our experimental model of porcine carotid angioplasty without radiological guidance induced a vascular wall reaction and permitted the quantification of this response. This porcine model may facilitate the study of vascular injury and its response to pharmacological interventions.

Exames anatomopatológicos transoperatórios: controle de qualidade / Transoperative anatomopathological examinations: quality control

Exames transoperatórios (ET) säo realizados rotineiramente em um hospital geral, e seus resultados determinam os diferentes procedimentos cirurgicos. OBJETIVO. Avaliar o grau de precisäo diagnóstica dos ET e identificar os tipos de erros mais freqüentes. MÉtodos. Foram estudados, prospectivamente, 2.152 ET realizados entre março de 1986 e setembro de 1991, no Hospital de Clínicas de Porto Alegre (HCPA). RESULTADOS. Os 2.152 ET corresponderam a 3,7 por cento dos 58.127 exames anatomopatológicos feitos nesse período. Os erros classificados como falsos positivos ocorreram oito vezes (0,4 por cento), os falsos negativos 39 vezes (1,8 por cento) e os diagnósticos postergados para os cortes em parafina (inconclusivos) atingiram 62 casos (2,8 por cento). Os órgäos mais freqüentemente examinados foram linfonodo (19,3 por cento), ovário (17,2 por cento), mama (16,6 por cento) e tiróide (12,4 por cento). A acurácia dos ET foi de 95 por cento, e quando excluídos os 64 casos inconclusivo, a precisäo diagnóstica atingiu 97,8 por cento. CONCLUSäO. Os erros diagnósticos (2,2 por cento) encontrados nos ET realizados no HCPA säo compatíveis com os dados citados na literatura mundial, que variam entre 0,7 por cento e 2,5 por cento

[Transoperative anatomopathologic examinations: quality control]. / Exames anatomopatológicos transoperatórios: controle de qualidade.

Frozen sections (FS) are usually performed in a General Hospital and are very useful for the surgical procedure orientation. PURPOSE--To verify the accuracy of the FS performed at the Hospital de Clínicas de Porto Alegre (HCPA), RS, Brazil. METHOD--2,152 FS were carried out between March 1986-September 1991, in a prospective study. RESULTS--3.7% of the conventional pathologic examinations (58,127), performed in the same period, correspond to the FS examined. When the FS diagnosis differed from the definitive one (in paraffin) it was classified as False Positive (0.4%), False Negative (1.8%) or inconclusive (2.8%). The organs more frequently examined were lymph nodes (19.3%), ovary (17.21%), breast (16.6%) and thyroid gland (12.4%). We observed accuracy indices in 95% of the FS examined, and in 97.8% when excluding the inconclusive ones. CONCLUSION--The accuracy indices of FS performed in HCPA were similar to the ones found in the literature, which vary from 90.4% to 98.5%.

Riedel's thyroiditis associated with high titers of antimicrosomal and antithyroglobulin antibodies and hypothyroidism.

Riedel's thyroiditis is a rare, chronic inflammatory disease of the thyroid gland. The aggressive fibrosis with extension beyond the thyroid into adjacent tissues contrasts with the diffuse, but intracapsular fibrosis of Hashimoto's thyroiditis. Most current studies refute the possibility of progression from a highly fibrosing form of Hashimoto's thyroiditis to a Riedel's thyroiditis based on the distinct clinical and laboratory data, although an unknown immunological basis is suggested for both diseases. The authors describe a patient with Riedel's thyroiditis, probably associated with Hashimoto's thyroiditis, sent to surgery because her cytological examination suggested thyroid malignancy. This patient had clinical and laboratory features of hypothyroidism and very high titers of antimicrosomal and antithyroglobulin antibodies, which decreased after surgery. Pathology studies disclosed Riedel's thyroiditis with intense lymphocytic infiltration suggestive of Hashimoto's thyroiditis. Quantitative immunohistochemical studies were not able to distinguish between both diseases.