Influence of the colon in liver regeneration of rats submitted to hepatectomy and colectomy

OBJECTIVE

to evaluate whether colectomy, associated with 70% hepatectomy, influences liver regeneration in rats.

METHODS

we distributed 18 Wistar rats in three groups of six animals each. In group I (sham), we performed laparotomy; In group II, colectomy + 70% hepatectomy; In group III, only 70% hepatectomy. On the 6th postoperative day, we collected blood by cardiac puncture under anesthesia, followed by euthanasia. We performed serum dosages of aspartate aminotransferase (AST), alanine aminotransferase (ALT), albumin and alkaline phosphatase (AF), hepatocyte growth factor (HGF) and transforming growth factor-α (TGF-α). We calculated liver regeneration by the formula: liver weight ratio per 100g body weight at the time of euthanasia / liver weight preoperatively projected for 100g body weight × 100.

RESULTS

ALT and AST levels were significantly lower in group II when compared with group III (p<0.001). Albuminemia showed significantly higher levels in group II. Levels of HGF and TGF-α in group II were significantly higher than in group III. The percentage of hepatic regeneration was significantly higher in group II than in group III.

CONCLUSION

Colectomy performed simultaneously with 70% hepatectomy had a positive influence on liver regeneration in rats. Further research is needed to reveal the molecular mechanisms of this effect and to characterize the colon influence in liver physiology.

Phenotypic variability of aprataxin gene mutations

The clinical and genetic features of three non-Portuguese and non-Japanese patients with aprataxin gene mutations are reported. Patient 1 came from Italy and presented with typical ataxia with ocular motor apraxia (OMA). She was homozygous for the W279X nonsense mutation, which is associated with the Portuguese founding haplotype. Patients 2 and 3 were French siblings and did not present with either OMA or hypoalbuminemia. They were compound heterozygous for the nonsense W279X mutation and a missense K197Q mutation.

The gene mutated in ataxia-ocular apraxia 1 encodes the new HIT/Zn-finger protein aprataxin

The newly recognized ataxia-ocular apraxia 1 (AOA1; MIM 208920) is the most frequent cause of autosomal recessive ataxia in Japan and is second only to Friedreich ataxia in Portugal. It shares several neurological features with ataxia-telangiectasia, including early onset ataxia, oculomotor apraxia and cerebellar atrophy, but does not share its extraneurological features (immune deficiency, chromosomal instability and hypersensitivity to X-rays). AOA1 is also characterized by axonal motor neuropathy and the later decrease of serum albumin levels and elevation of total cholesterol. We have identified the gene causing AOA1 and the major Portuguese and Japanese mutations. This gene encodes a new, ubiquitously expressed protein that we named aprataxin. This protein is composed of three domains that share distant homology with the amino-terminal domain of polynucleotide kinase 3'- phosphatase (PNKP), with histidine-triad (HIT) proteins and with DNA-binding C2H2 zinc-finger proteins, respectively. PNKP is involved in DNA single-strand break repair (SSBR) following exposure to ionizing radiation and reactive oxygen species. Fragile-HIT proteins (FHIT) cleave diadenosine tetraphosphate, which is potentially produced during activation of the SSBR complex. The results suggest that aprataxin is a nuclear protein with a role in DNA repair reminiscent of the function of the protein defective in ataxia-telangiectasia, but that would cause a phenotype restricted to neurological signs when mutant.

Immunological and clinical evaluation of chagasic patients subjected to chemotherapy during the acute phase of Trypanosoma cruzi infection 14-30 years ago

We recently evaluated the in vitro proliferative response and interferon (IFN)-gamma production of peripheral blood mononuclear cells from a group of 25 people who were treated for Chagas' disease during the acute phase of Trypanosoma cruzi infection and followed up for a period of 14-30 years. On the basis of the parasitological and serological tests, the individuals were classified as cured (C), dissociated, or not cured (NC). Members of group C (the group without cardiac alterations) presented significantly stronger proliferative response against the parasite antigens, with secretion of high levels of IFN-gamma in comparison with the NC group, raising a question about the role of this cytokine in the curing of human T. cruzi infection. Severe cardiac alterations were observed only in 1 of 25 patients, which suggests that treatment benefited the patients.

Genetic characterization of Trypanosoma cruzi directly from tissues of patients with chronic Chagas disease: differential distribution of genetic types into diverse organs

We have previously shown that a low-stringency single-specific primer-polymerase chain reaction (LSSP- PCR) is a highly sensitive and reproducible technique for the genetic profiling of Trypanosoma cruzi parasites directly in tissues from infected animals and humans. By applying LSSP-PCR to the study of the variable region of kinetoplast minicircle from T. cruzi, the intraspecific polymorphism of the kinetoplast-deoxyribonucleic acid (kDNA) sequence can be translated into individual kDNA signatures. In the present article, we report on our success using the LSSP-PCR technique in profiling the T. cruzi parasites present in the hearts of 13 patients with chagasic cardiopathy and in the esophagi of four patients (three of them with chagasic megaesophagus). In two patients, one with the cardiodigestive clinical form of Chagas disease and the other with cardiopathy and an esophageal inflammatory process, we could study both heart and esophagus and we detected distinct kDNA signatures in the two organs. This provides evidence of a differential tissue distribution of genetically diverse T. cruzi populations in chronic Chagas disease, suggesting that the genetic variability of the parasite is one of the determining factors of the clinical form of the disease.

Cardiac autonomic denervation in congestive heart failure: comparison of Chagas' heart disease with other dilated cardiomyopathy

Congestive heart failure (CHF) is associated with activation of the cardiac sympathetic nerves. However, impairment of the sympathetic nerve terminals in patients with CHF has been indicated by studies showing reduction of cardiac norepinephrine uptake and stores. This investigation studies the histochemical evaluation of the sympathetic nerve terminals in CHF. The cardiac parasympathetic innervation was also studied to address the question of specificity of the presumed sympathetic denervation. Nineteen patients with CHF underwent cardiac transplantation or partial ventriculectomy, which provided the heart tissue. In 11 of them, the dilated cardiomyopathy was associated with Chagas' disease. Inflammatory process and fibrosis were studied histologically. The sympathetic and parasympathetic nerve fibers were visualized through histochemical techniques for, respectively, catecholamines and acetylcholinesterase activity. By using a computer-assisted morphometric program, the inflammation, fibrosis, and parasympathetic innervation were quantified. Moderate to severe fibrosing myocarditis characterized the hearts of the chagasic patients. In cardiomyopathies not associated with Chagas' disease, the inflammation was discrete, if present, but the amount of fibrosis was similar to that found in Chagas' cardiomyopathy. Reduction of both kinds of nerve terminals occurred in the heart of all patients. The parasympathetic denervation was proven to be more severe in chagasic cardiomyopathy. Our data on the heart innervation indicate a progressive autonomic denervation in heart failure. In Chagas' heart disease, the denervation seems to be more severe or rapid, probably because of the sustained inflammatory process.

[Images in Venus' mirror: woman, nursing and modern times]

This paper discusses the process of nursing professional identity construction in modernity. We utilize the ideas of category gender (Lobo, 1991) and modern person (Duarte, 1986). The modernity as a historical process establishes the emergence of work as a central category in the public X private relationship. Understanding the profession as form of construction and public presentation of the modern person, we discuss the nursing professional identity process in relation to its female basis. Working on nursing ethnographic bibliography, we identify a picture that gives to the female basis of the profession the greater cause of dilemmas such as: technical competence, vocation and identity.

Aortic reconstruction with crimped bovine pericardial conduits

BACKGROUND AND AIM OF THE STUDY

A bovine pericardial conduit processed in glutaraldehyde was designed, incorporating the principle of crimping used for synthetic vascular prostheses. The crimping process did not affect the integrity of collagen fibers and tissue structure. This conduit, designed for aortic reconstruction, is available in different sizes, with or without a biological valve.

METHODS

Between October 1989 and May 1997, 40 patients with aortic dissection, aortic aneurysm, aortic coarctation or aortoiliac occlusive disease underwent aortic reconstruction using this vascular substitute. Procedures included total reconstruction of the ascending aorta and aortic valve with reimplantation of coronary arteries (nine patients), single ascending thoracic aorta (six), descending thoracic aorta (two), aortic arch (one) and thoracoabdominal aorta (one); the abdominal aorta was reconstructed in 21 cases, including those undergoing aortoiliac or aortofemoral bypass.

RESULTS

The hospital mortality rate was 20% (eight patients); causes of deaths were low cardiac output, recurrence of aortic dissection, multiple organ failure and bleeding. Mean follow up was 3.6 years; total follow up was 114 patient-years. Late conduit-related complications occurred in four patients, including a limb obstruction in one patient subjected to aortofemoral bypass and infection of three resulting in pseudoaneurysm (incidence of 3.5 +/- 1.8% per patient-year). All underwent reoperation. There were four late deaths due to sudden death, coronary artery disease, pneumonia and metabolic complications of diabetes and renal failure (incidence of 3.5 +/- 1.8% per patient year). The eight-year actuarial survival rate was 63.7 +/- 11.6%, including hospital mortality, and the eight-year actuarial freedom from conduit failure due to primary tissue structural degeneration was 100%.

CONCLUSIONS

The crimping design provides a circular tube which makes construction of the anastomosis easier, retains its shape with bending, and avoids kinking. The material is very soft, easy to handle and suture, coapts nicely to suture lines resulting in a hemostatic anastomosis. The eight-year follow up demonstrated a satisfactory performance without report of fibrosis, calcification or aneurysmal dilation.

Mitral valve replacement with glutaraldehyde preserved aortic allografts

OBJECTIVE

To present long-term results after mitral valve replacement with stent mounted glutaraldehyde preserved aortic allografts in patients older than 15 years. The clinical support for this study was to combine the glutaraldehyde technique of biological tissue preservation with the advantages of allografts when compared to xenografts. This was demonstrated in previous studies using other methods of tissue processing.

METHODS

Between September 1984 and November 1994, 70 patients aged 16-77 years (mean 35.4 years) underwent mitral valve replacement with this preserved and mounted allograft. Of these, 40 patients (57.2%) were aged 16-35 years and 15 (21.4%) were 20 years old or younger; 46 (65.7%) were females and 24 (34.3%) males. Single mitral valve replacement was performed in 60 patients and 10 were also subjected to other combined cardiac procedures. Human aortic valves were obtained during routine autopsy, processed in glutaraldehyde and mounted into flexible stents, using the same technique as that used for porcine bioprostheses.

RESULTS

Hospital mortality was 1.4%. Total follow-up was 543.1 patient-years, corresponding to a mean follow-up of 7.9 years per patient. Echocardiography demonstrated a hemodynamic performance similar to porcine bioprostheses. Late mortality was 0.7 +/- 0.6% per patient-year and the causes were congestive heart failure in 2, prosthetic endocarditis in 1 and acute myocardial infarction in 1. The 12-year actuarial survival was 92.4 +/- 3.2%. The incidence of late complications was 5.2 +/- 1.2% per patient-year, including congestive heart failure, prosthetic endocarditis, periprosthetic leak, thromboembolic episodes, recurrence of rheumatic disease, coronary artery disease and allograft failure. Complications related to heart disease represented 2.8 +/- 0.6% and allobioprosthesis-related 2.4 +/- 0.5% per patient-year. The 12-year actuarial freedom from primary valve failure was 81.0 +/- 15.0%. The incidence of reoperations was 1.5 +/- 0.8% per patient-year and the main indication was prosthetic endocarditis. Other causes were periprosthetic leak, aortic insufficiency in the native aortic valve and allobioprosthesis dysfunction. Functional results demonstrated a significant improvement in patients clinical condition.

CONCLUSION

This 12-year follow-up shows a very low incidence of primary allograft failure for patients older than 15 years undergoing mitral valve replacement, and much superior than our results with porcine bioprosthesis in the same age group. This supports our assumption that this investigational valve represents a new advance in cardiac valve surgery.

IFN-gamma in human Chagas' disease: protection or pathology?

An apparently paradoxical role for IFN-gamma in human Chagas' disease was observed when studying the pattern of cytokine production by peripheral blood mononuclear cells (PBMC) obtained from two groups of chagasic patients after specific stimulation with Trypanosoma cruzi-derived antigens. The groups studied were 1) patients treated with benznidazole during the acute phase of Trypanosoma cruzi infection and 2) chronically infected untreated patients. In the treated group, higher levels of IFN-gamma were produced by PBMC from individuals cured after treatment when compared to non-cured patients. In contrast, in the chronically infected group (not treated) higher levels of IFN-gamma were produced by PBMC from cardiac patients in comparison with asymptomatic (indeterminate) patients. This apparently paradoxical role for IFN-gamma in human Chagas' disease is discussed in terms of the possibility of a temporal difference in IFN-gamma production during the initial stages of the infection (acute phase) in the presence or absence of chemotherapy. The maintenance of an immune response with high levels of IFN-gamma production during the chronic phase of the infection may favor cure or influence the development of the cardiac form of the disease.

[The Rockefeller Foundation and the construction of a professional identity in nursing during Brazil's first Republic]

This article deals with the institution of professional nursing in Brazil during the First Republic, based on a study of documents left by the US nursing mission recruited during the 1920s by the Rockefeller Foundation, in association with the National Public Health Department. Certain excerpts from these documents are representative of main events and references within the field and can be considered emblematic of the construction of a professional identity. It is concluded that Brazilian nurses defined their identity around three basic lines: gender, race, and social origin.

[Understanding the idea of nursing for use in professional practice]

This study is about the comprehension analysis of female students at graduation courses in Nursing on the meaning of Nursing as a female profession, in the light of their reasons why they have chosen it. Qualitative method and social representation have been used for data analysis. The results showed that Nursing is a profession of love for the fellowman and it is a way to get closer to God, but it is also a challenge and a struggle for a better profession.

Assessment of functional capacity during gait using a reciprocal propulsion orthosis (ARGO)--a comparative study with a conventional mechanical orthosis

One subject (male, 24 years) with an incomplete motor and sensitive SCI, neurological level C6-C7 was submitted to a comparative study during gait using an advanced reciprocating gait othosis (ARGO) and a conventional mechanical orthosis (CMO) and respiratory and metabolic variables were compared at peak effort and in the second minute of recovery. We found that the ARGO, as with the CMO, not guarantee gait independence but the ARGO does enable a more functional gait pattern with a more efficient ventilation. The ratio of CO2/O2 showed that ARGO enable aerobic conditions of work and the energy expenditure using is significantly lower than CMO.

Effect of granulocyte inhibitory factor on granuloma formation in mice infected with Schistosoma mansoni

Mononuclear cells from patients infected with Schistosoma mansoni were able to produce a soluble material that inhibited the granulocyte cytotoxicity against schistosomula in a complement-dependent killing assay. This granulocyte inhibitory factor (GIF) appears to exist preformed in the mononuclear cells of patients, but it can also be released in the supernatant after antigenic stimulation (lymphokine-like). Only T lymphocytes were able to mediate the inhibition of granulocyte cytotoxicity against schistosomula in vitro. The treatment of S. mansoni-infected mice with GIF induced a significant decrease in the liver granuloma size.

Note on the classification of the Leishmania sp. responsible for cutaneous leishmaniasis in the East Central Region of Brazil

The authors studied a species of Leishmania which is the causative agent of cutaneous leishmaniasis in Mato Grosso, Brazil. The parasite displays unusual characteristics which do not fit exactly into either the L. mexicana or L. brasiliensis complexes. The buoyant density DNA resembles that of the L. mexicana complex but the culture and hamster inoculation results resemble those of the L. brasiliensis complex. Further comparative studies are required to elucidate the relationship of the Mato Grosso Leishmania to the L. mexicana complex.