Determining reference ranges for immunological cells of healthy indigenous individuals from a region in Brazil

Morais et al. conducted a pioneering study with Brazilian indigenous populations to determine reference values for immunologic cells from healthy adult individuals. The main findings included a higher relative median for T lymphocyte subsets in females than males, and T CD3+, T CD4+, and T CD8+ relative values were statistically different when compared with Brazilian populations from other Brazilian regions. The relative medians of CD3+, CD4+, and CD8+ T cells were significantly higher in women than in men in a healthy indigenous population. Demographic and ethnic diversity of the Brazilian population can be associated with quantitative modifications in the immunologic cells of healthy individuals.

OBJECTIVE

The establishment of reference values for a subset of leukocytes is common in clinical practice, and ethnic variations are strongly associated with disease development. In Brazil, indigenous people are vulnerable to infections, and few studies have described the health and disease conditions of this population. This study aimed to provide reference values for immunological cell subsets in indigenous Brazilians living in the state of Mato Grosso do Sul.

METHODS

Flow cytometry and 4-color combinations of monoclonal antibodies were used to characterize cells. A total of 115 healthy adults, mostly females (72%), were included in the study. The results are presented as mean and median (2.5%-97.5% percentiles) for T and B lymphocytes, CD4+ T cells, CD8+ T cells, Natural Killer cells, monocytes, and dendritic cells, providing an average immunological profile for the population in question.

RESULTS

The relative medians of CD3+, CD4+, and CD8+ T cells were significantly higher in women than in men in a healthy indigenous population.

CONCLUSION

To our knowledge, cell reference data from indigenous Brazilians are unknown in the literature. The immune cell results presented in this pioneering study will contribute to the clinical and laboratory evaluation of the Brazilian indigenous population, especially given the important differences when compared with other Brazilian ethnic groups.

Decreased serum T3 after an exercise session is independent of glucocorticoid peak

Physical exercise increases serum glucocorticoids, which is believed to be involved in the fall of T3 after high intensity exercise. The objective was to evaluate whether a physical exercise session alters the thyroid economy and adrenal axis in humans, and the possible role of corticosteroids in thyroid function disturbance. Active but not athlete subjects were enrolled in an open field competition and cortisol, TSH, T3, and T4 were measured before and after the race. To give new insights into the mechanisms underlying the changes in thyroid economy after exercise, we used a rat model to evaluate the impact of blocking corticosterone synthesis during treadmill exercise by metyrapone administration. Cortisol levels increased 1.5-fold (from 28.2±3.8 to 42.2±2.2 μg/dl; p<0.05), while serum T3 decreased by 13% (from 115±5 to 99±5 μg/dl; p<0.05) 6 h after the race in humans. Also, in rats, glucocorticoid increased by 2-fold while T3 decreased 15% after exercise session (p<0.05). However, the complete blockage of corticosterone peak did not impair serum T3 decrease observed in rats submitted to exercise. Interestingly, the lack of corticosterone peak led not only to lower serum T3, but also to decreased serum T4, indicating that corticosterone might be fundamental for the maintenance of serum thyroid hormone levels after high intensity exercise. Although cortisol increases and T3 decreases after high intensity exercise in both humans and rats, it does not seem to be a cause-effect response since pharmacological blockage of corticosterone peak does not modulate T3 response.

Diagnosis of canine brucellosis by ELISA using an antigen obtained from wild Brucella canis

An indirect ELISA test was developed for the diagnosis of Brucella canis infection in dogs. A bacterial whole cell extract was used as a solid phase antigen, using B. canis isolated from an infected animal. Sera from culture-positive and healthy negative animals were used as internal reference controls. The cut-off point was determined by a mathematical formula for a statistically valid value, which defined the upper prediction limit, based on the upper tail of the t-distribution of 21 negative control sera readings, for the confidence level of 99.5%. The sensitivity and specificity of the ELISA test were 95% and 91%, respectively. The ELISA test showed a significant concordance index (K=0.84) with the agar gel immunodiffusion test. The reliability of the ELISA for the detection of infected animals was established by a double blind study testing 280 sera provided by serum banks from different diagnostic and research institutions and analyzed by ROC Curve.

Corporeal Weight Gain and Metabolic Syndrome in Living Kidney Donors After Nephrectomy

The number of healthy individuals undergoing unilateral nephrectomy for kidney donation is increasing world-wide. Obesity and nephron reduction could promote a decline in the glomerular filtration rate (GFR) and an increase in urinary protein excretion in these individuals. Metabolic Syndrome (MS) is also a risk factor for these patients. This study evaluated GFR, urinary protein excretion, and the possibility of one or more components of MS in this group.

METHODS

Twenty live kidney donors were evaluated at an average of 10 years after nephrectomy. We obtained measurements of systolic blood pressure, diastolic blood pressure, and waist circumference. We estimated renal function, urinary protein excretion, triglycerides, high-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and fasting plasma glucose levels. The GFR was calculated through the estimated creatinine clearance using the Cokcroft-Gault equation (eGFR).

RESULTS

Of the 20 participants, four developed MS. The patients with a greater number of MS components showed a greater eGFR. Only seven donors (35%) showed a normal blood pressure. Serum creatinine level changes were observed in three patients, and in five there was increased urinary protein excretion.

CONCLUSION

This study showed the possibility that corporeal weight gain and MS may be additional overburdens on the GFR of the remaining kidney.

Coherence of elementary excitations in a disordered electron system

The localization properties of the single-particle and collective electron excitations were investigated in the intentionally disordered GaAs/AlGaAs superlattices by weak-field magnetoresistance and Raman scattering. The localization length of the individual electron was found to be considerably larger than that of the collective excitations. This suggests that the disorder has a weaker effect on the electrons than on their collective motion and that the interaction which gives rise to the collective effects increases localization.

Isolation of Neospora caninum from the brain of a naturally infected dog, and production of encysted bradyzoites in gerbils

Neospora caninum was isolated from the brain of an adult dog in Brazil. Cerebral tissue from the dog was inoculated into Mongolian gerbils. Gerbils were euthanized 3-4 months later and bradyzoite-containing tissue cysts were observed in their brains. N. caninum (designated NC-Bahia) was isolated in cell culture after inoculation with tissue cysts from the gerbils. The identity of the parasite was confirmed by immunohistochemical examination and polymerase chain reaction (PCR). Gerbils may be a useful alternative to immunosuppressed mice for isolation of N. caninum and for production of encysted bradyzoites.

A rapid assay of endotoxin in whole blood using autologous neutrophil dependent chemiluminescence

A rapid (30 min) whole blood assay for the detection of lipopolysaccharide (LPS) is described. This chemiluminescent (CL) assay utilizes the CR1 and CR3 receptor-induced oxidant production of polymorphonuclear leucocytes as a detection platform. The differential priming of neutrophils in whole blood by LPS-antibody complexes allows the specificity of the assay to be achieved. Oxidant released in response to complement opsonized zymosan results in luminol oxidation and subsequent light emission. This is dependent on heat labile putative complement proteins in the plasma. The assay consists of a control which measures baseline whole blood neutrophil oxidant production. The test assay contains murine monoclonal IgM antibody against the Lipid A epitope of LPS and measures the enhanced chemiluminescent response of the neutrophils in the presence of LPS-antibody complexes. Maximal sensitivity of the CL assay is dependent upon optimal antigen-antibody equivalence and duration of pre-incubation with the whole blood sample. The quantification of LPS is possible by inclusion of a positive control containing a maximally reactive LPS dose (800 pg/ml Escherichia coli 055:B5 LPS at an antibody concentration of 0.8 microg/assay). The CL assay is insensitive to variations in patient neutrophil concentration over a minimum range of 0.5 to 20 x 10(9) cells/l. The CL assay is widely reactive with the LPS of many strains of gram negative bacteria but not with the cell wall products of gram positive bacteria or Candida and Aspergillus. In comparison to acid extraction chromogenic LAL, the CL assay demonstrates superior recovery precision and accuracy in in vitro studies. This was reproducible over a wide range of LPS concentrations (0.017-1.6 EU/ml or 20-2000 pg/ml). This assay may be a clinically useful tool for the diagnosis of infection or endotoxin in patients.

Colorectal adenocarcinoma in Crohn's disease

OBJECTIVE

The authors' aim was to review the clinical features and estimate the long-term survival of patients with colorectal carcinoma complicating Crohn's disease.

SUMMARY BACKGROUND DATA

Recent studies have demonstrated a significantly increased risk of colorectal carcinoma in patients with Crohns disease.

METHODS

The authors reviewed retrospectively the medical records of 30 patients with Crohn's disease admitted to The Mount Sinai Hospital between 1960 and 1989 in whom colorectal adenocarcinoma developed. All patients were operated on and follow-up was complete for all patients to 10 years after operation, to the time of death, or to the closing date of the study in December 1989.

RESULTS

The 30 patients in the series had 33 colorectal adenocarcinomas; three patients (10%) presented with two synchronous cancers. The patients were relatively young (mean age, 53 years) and had long-standing Crohn's disease (duration >20 years in 87%). The 5-year actuarial survival was 44% for the overall series: 100% for stage A, 86% for stage B, 60% for stage C. All five patients with excluded bowel tumor died of large bowel cancer within 2.4 years; by contrast, the actuarial 5-year survival for patients with in-continuity tumors was 56%.

CONCLUSIONS

The incidence, characteristics, and prognosis of colorectal carcinoma complicating Crohn's disease are similar to the features of cancer in ulcerative colitis, including young age, multiple neoplasms, long duration of disease, and greater than a 50% 5-year survival rate (without excluded loops). These observations suggest the advisability of surveillance programs for Crohn's disease of the colon similar to those for ulcerative colitis of comparable duration and extent.

Mast cell modulation of macrophage procoagulant activity and TNF production

The expression of surface procoagulants by macrophages represents an important mechanism underlying local fibrin deposition at sites of extravascular inflammation. Mast cells by virtue of their perivascular location are in a potent position to influence the inflammatory process. The present studies investigated the role of the mast cell in the generation of macrophage procoagulant activity (PCA) and tumor necrosis factor (TNF) production. Mast cell lysates caused a marked induction of macrophage PCA (dose and time dependent) and TNF release while whole mast cells had little effect. This effect was prevented by the tyrosine kinase inhibitor herbimycin. At the molecular level, Northern blot analysis revealed marked induction of the murine macrophage tissue factor transcript in response to incubation with mast cell lysate compared to control. These studies thus suggest that mast cell-macrophage interactions promote macrophage-mediated fibrin deposition and TNF release and that this effect is in part mediated via induction of tyrosine phosphorylation. These observations suggest novel mechanisms of involvement of the mast cell in the inflammatory microenvironment and macrophage activation.

Survival with colorectal cancer in ulcerative colitis. A study of 102 cases

OBJECTIVE

This study was undertaken to correlate postoperative survival of patients with ulcerative colitis-associated colorectal cancer with the stage, configuration, size, and mucin content of the tumor.

SUMMARY BACKGROUND DATA

The factors influencing prognosis in colorectal cancer in the general population are well accepted, but less is known about their influence in cases of colorectal cancer associated with ulcerative colitis.

METHODS

The authors reviewed the records of 102 patients with ulcerative colitis-associated colorectal cancer admitted to The Mount Sinai Hospital between 1959 and 1988. Tumors were classified on independent pathologic review according to histologic stage, configuration, size, and mucin content. Comparisons among survival curves were tested by the generalized Wilcoxon test. Cox regression models were used to examine the joint effects of selected clinicopathologic features on postoperative survival rates.

RESULTS

Complete follow-up was obtained for 93 patients (92%). Overall 5-year actuarial survival was 52%. When factors were analyzed one at a time, survival was significantly poorer among patients with advanced cancer stage, larger tumor size, infiltrating and ulcerating configuration, and high mucin concentration. On multivariate analysis by the Cox regression model, however, only cancer stage emerged as a factor independently predicting survival.

CONCLUSIONS

For colitis-associated colorectal cancers, as for noncolitic cancers, histologic stage is the most important variable determining postoperative survival. The distribution of stages in our series and the survival rates within each stage did not differ appreciably from the distributions and survival rates reported for noncolitic colorectal cancers.

Portal endotoxemia stimulates the release of an immunosuppressive factor from alveolar and splenic macrophages

Impairment of cell-mediated immunity is both a common manifestation of critical illness and a potential cause of increased infectious morbidity and mortality. The mechanisms responsible for alterations in systemic immune regulation are incompletely understood; however, monocytes and fixed tissue macrophages appear to play a central role. We have previously shown that infusion of gram-negative organisms into the portal vein, but not into the systemic circulation, induces suppression of delayed hypersensitivity responsiveness in vivo and of mitogen-stimulated lymphocyte proliferation in vitro. The present studies were undertaken to probe the mechanisms of this suppression. Rats received 3 x 10(8) killed Pseudomonas aeruginosa via the inferior vena cava or the portal vein; they were sacrificed 24 hr later and the mitogen-driven proliferative responses of isolated splenocytes were assayed. Portal infusion resulted in significant suppression of Con A-induced proliferative responses (15.5 +/- 2.7 cpm x 10(-3) compared to 68.6 +/- 9.8 cpm x 10(-3) for infrahepatic vena cava-infused animals and 48.0 +/- 5.4 cpm x 10(-3) for nonoperated controls). Suppression was shown to be a consequence of the release of a soluble suppressive factor from splenic adherent cells. Suppression of the proliferative responses of control lymphocytes could also be induced by a soluble factor present in culture supernatants of alveolar macrophages harvested from portally infused animals (4.7 +/- 0.4 cpm x 10(-3) vs 88.6 +/- 27 cpm x 10(-3) for systemically infused animals and 60.1 +/- 8.4 cpm x 10(-3) for nonoperated controls). The stimulus for the release of this factor was not endotoxin, but a second factor released from the liver.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma of the small intestine in Crohn's disease

Nineteen patients admitted to The Mount Sinai Hospital with Crohn's disease between 1960 and 1989 had 20 adenocarcinomas of the small intestine. Sixteen patients had regional enteritis and three, ileocolitis. There were 15 males and four females. Carcinomas occurred in association with fistulas (four patients), fistulous tracts (three patients), excluded bowel (five patients/six cancers) and multiple strictures (three patients). None of the patients in our study had cancer develop in the first decade of Crohn's disease, and 11 had carcinoma in the third decade. As cancers occurred in three patients with multiple strictures admitted for strictureplasty, we recommend that all strictures be widely opened and carefully examined prior to strictureplasty, with frozen section biopsies of all suspicious areas. The possibility of small intestinal Crohn's carcinoma should be suspected in patients with long-standing disease, with or without excluded bowel, who present with sudden change in symptoms, especially after a lengthy quiescent period. Cancer should also be considered in patients in whom complete obstruction fails to resolve with adequate decompression and in those with multiple strictures.

Malignant colorectal strictures in Crohn's disease

One hundred thirty-two of 980 patients (13.5%) with Crohn's disease (CD) involving the colon, admitted to The Mount Sinai Hospital between 1959 and 1985, developed 175 colonic strictures. Thirty-three patients developed more than one stricture. The frequency was twice as great in colitis (19%) as in ileocolitis (11%). Ten malignant strictures were identified in nine patients (three ileocolitis, six colitis). One of these patients had three strictures (two malignant, and one benign), and two had two strictures (one malignant and one benign). The frequency of cancer in patients with stricture (6.8%) was higher than in those without stricture (0.7%, six of 848, p less than 0.001). There were no differences in clinical symptoms between patients with benign and malignant stricture. Seventeen of 165 benign strictures (10.3%) were long, extending over more than one anatomical segment of colon, but all 10 malignant strictures were short (p less than 0.0001). The age at the diagnosis of stricture was higher in the nine patients with malignant stricture than in the 123 patients with benign stricture (mean age 57.2 vs. 41.4 yr, respectively, p less than 0.01). The proportion of strictures that were malignant increased with duration of disease from 3.3% with less than 20 yr of CD, to 11% with CD of 20 yr or more. All nine patients with malignant stricture were treated surgically, and four of the nine died of colon cancer during a mean follow-up of 4.3 yr. Prognosis was worse in six other nonstricture cancers in this series, with five colon cancer deaths during mean follow-up of 1.6 yr. In view of the high rate of malignancy, 6.8% in this series, colonoscopy with biopsy is essential in Crohn's disease patients with colonic strictures, and surgery must be considered when a stricture cannot be fully assessed during colonoscopy.

Colorectal cancer in ulcerative colitis. Influence of anatomical extent and age at onset on colitis-cancer interval

We have examined the age at onset of both ulcerative colitis and colitis-associated colorectal cancer in 100 patients seen at Mount Sinai Hospital between 1959 and 1988. There were 85 patients with extensive colitis and 15 with left sided colitis. There was a strong direct correlation between the age at onset of ulcerative colitis and age at diagnosis of cancer (p less than 0.0001); this correlation was found both in patients with extensive colitis (p less than 0.0001) and in those with left sided colitis (p less than 0.005). Patients with left sided colitis developed both their colitis and their cancers about a decade later than did those with extensive disease, but the mean duration of colitis before diagnosis of cancer was virtually the same (about 21 years) in both groups, irrespective of the age at onset of disease.

[Experience with peroral biopsy of the small intestine at the University Hospital--Federal University of Rio de Janeiro]

The experience with 103 jejunal biopsies in the Rio de Janeiro University Hospital--UFRJ, from January 1983 to June 1985 is presented. It is reported the effectiveness of the method and the low number of complications. The importance as a valuable complementary method of diagnosis and the usefulness in the small intestine disease's scientific investigation is emphasized.

Epidemiological and demographic considerations. Hypertension in underdeveloped countries

Data obtained from subjects in the city of São Paulo show that hypertension will be an increasing major public health problem as the adult population grows older. Information from over 5000 subjects indicated that males had a prevalence of hypertension almost 3 times that of females, with this difference being significant up to 44 years of age. Although mild and moderate forms of hypertension increased with age among both males and females, black males were noted to have diastolic blood pressures greater than or equal to 90 mm Hg in almost twice the frequency of their white counterparts. In addition, the demographic tendencies in São Paulo of increasing older age groups over the last 2 decades compare similarly with data from other developed Western countries. Thus, the importance of hypertension in underdeveloped countries must not be underestimated.

Hypertension among female workers in São Paulo, Brazil. Predictors and joint effects

Previous analysis based on data derived from a prevalence study of hypertension among workers in different economic activities in the Greater Metropolitan Area of São Paulo, Brazil, have shown separate effects of biologic and social attributes on diastolic blood pressure levels (DBP). The present paper explores joint effects of sociodemographic, anthropometric, and behavioral characteristics on blood pressure levels. For that purpose, the Morgan-Sonquist procedure on interaction effects in the prediction of DBP levels was used. Six independent variables emerged as predictors: age, Quetelet index, occupation, schooling years, subsector of the economy, and smoking. Very young and lean women who were also smokers had the lowest mean DBP levels (66.1 mm Hg). Young, overweight women without college education showed intermediate levels (71.5 mm Hg). Highest levels were found among older women in production-linked occupations engaged in transportation and metallurgy activities (89.5 mm Hg). The study suggests that the potential role of work-related characteristics on blood pressure levels is greatest among older women.

Hypertension and economic activities in São Paulo, Brazil

A study of the prevalence of hypertension was undertaken among workers in 10 subsectors of the economy in São Paulo, a major urban-industrial area of Brazil. Included in the study were 5500 subjects 15-65 years of age, employed in 57 randomly selected firms. Hypertension rates (DBP greater than or equal to 90 mm Hg) were higher among males up to 44 years of age. There was a decreasing gradient from mild to moderate and severe forms in all groups. Severity tended to increase with age in all groups. Black males showed higher rates than whites (29.2% vs 16.7%, p less than 0.05), the excess being partially accounted for by moderate and severe forms (40% vs 20%). Subjects who overworked showed a trend toward higher hypertension rates. Higher rates in four subsectors (metallurgy, finance, transport, and journalism), aside from the distribution of known risk factors and job selection, may reflect a variety of work-related stressors.