EFFECTS OF PROTEIN-DEFICIENCY AND NATURAL INTESTINAL INFECTION WITH GIARDIA-LAMBLIA ON JEJUNAL INTRAEPITHELIAL LYMPHOCYTES IN RATS OF DIFFERENT AGES

1. The interaction between experimental protein deprivation and natural intestinal infection by Giardia lamblia was studied in terms of its effects on the intraepithelial lymphocyte (IEL) population and morphology of the jejunal mucosa of rats of different ages.2. Young, adult and old male Wistar rats received a protein-deficient diet (2% casein) or a control diet (20% casein) for 42 days. Mucosal height and the number of lymphocytes located among 500 consecutive epithelial cells (EC) along the villi or crossing the basement membrane were determined in PAS-stained jejunal fragments.3. The number of IEL increased progressively with animal age, from 14 to 25 per 100 epithelial cells, with significant differences between age ranges. However, the number of IEL did not differ between control and protein-deficient rats in any of the age groups. The proportion of lymphocytes crossing the basement membrane was approximately two-fold greater in young (2.8/100 EC) and adult (5.8/100 EC) protein-deficient animals than in their respective controls (1.6 and 2.8/100 EC). The intensity of parasite colonization was moderate, from 3 to 5/100 EC and did not differ between groups. The pattern of morphologic changes of jejunal mucosa in protozoal infection did not differ between control and protein-deficient animals in any of the three age groups.4. We conclude that intestinal infection with Giardia lamblia probably stimulated the local immune response, masking the reduction of the IEL population induced by protein deficiency. The increase in lymphocyte numbers with age may be related to prolonged antigenic stimulation promoted by infection.

Collagen type VI is a component of the extracellular matrix microfibril network of the prostatic stroma

Stroma-epithelium relationships are of great relevance in prostatic morphogenesis and physiology, However, little knowledge exists about either stromal cells or extracellular matrix composition and arrangement in this system, Ultrastructural analysis revealed the existence of a microfibrillar system which occupies large areas of the rat prostatic stroma, In this work, we have applied immunocytochemistry and an ATP treatment for the ultrastructural identification of collagen type VI microfibrils, aiming at examining its participation in the prostatic microfibrillar network. Immunocytochemistry was also extended to a human case of prostatic nodular hyperplasia, Both methods succeeded in identifying collagen type VI in the rat ventral prostate, Collagen type VI is evenly distributed throughout the stroma but mainly associated with the basal lamina, collagen fibrils, and around the stromal cells, the use of ATP treatment allowed for the discrimination between collagen type VI and elastin-associated microfibrils, and demonstrated that these two classes of microfibrils establish an extended, mixed, and open network. The same aspects of association with the basal lamina, with stromal cells (particularly with smooth muscle cells), and with fibrillar components of the stroma were observed in the human tissue, We suggest that the collagen type VI and elastin-associated microfibril system may be involved in the control of some aspects of cellular behavior and may also play a structural role, maintaining the organ integrity after the deformations occurring under smooth muscle contraction.

Hormonal therapy in the senescence: Prostatic microenvironment structure and adhesion molecules

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Gut intraepithelial lymphocyte counts in neonates, infants and children

Intraepithelial lymphocyte (IEL) counts were histologically assessed in the jejunum, ileum and appendix of 39 neonates (0-28 days), 32 infants (1-9 months) and 13 children (1-9 years). Small intestinal mucosa samples were obtained from 73 autopsies, and from 8 surgical and 3 aspirative biopsies. IEL counts of specimens from the jejunum, ileum and appendix gave similar results in the same patient. The number of IEL counts was significantly lower in neonates for all three segments. The difference between infants and children was more marked in the jejunum than in the ileum, although this was not significant. In the appendix, there was no difference between the different age groups. Our results indicate that postnatal expansion of IEL occurs homogeneously along the gut after the neonatal period.

Subcutaneous and testicular metastasis from prostatic adenocarcinoma with neuroendocrine differentiation

The pathological finding of testicular metastasis in cases of disseminated prostatic adenocarcinoma is rare, but was more frequently reported in the past, when bilateral castration was performed more often. The existence of skin and subcutaneous metastasis adds a worse prognosis, because generally it is sign of advanced disease with an average survival time of less than one year. The synchronous occurrence of such metastasis has not been described previously, neither their association to neuroendocrine differentiation. The presence of such differentiation of prostatic adenocarcinoma represents a very unfavorable prognostic factor, as suggested in recent literature. Herein, we discuss the case of a 53 year old man, who presented with macroscopic hematuria and frequency associated to several painless subcutaneous nodules in left axilla and shoulder, as well as in the lower abdominal wall. The right testis was painful, endured and on rectal examination, the prostate was diffusely enlarged. Serum PSA was elevated, reaching 1760 ng/ml and prostatic biopsy disclosed a Gleason 10 prostatic adenocarcinoma with neuroendocrine differentiation. The same pathological pattern was detected in the right testis and in all subcutaneous nodules, documented by positive staining of chromogranin, a marker of neuroendocrine cells. He was submitted to a prostate tunnelization and maximal androgen blockade plus adjuvant chemotherapy, nevertheless, he died 5 months latter.