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Biomedical subjects

M M Campos

Publications and source records attributed to M M Campos.

At least 37 records · Page 2Linked to original sources

Modulation of kinin B1 but not B2 receptors-mediated rat paw edema by IL-1beta and TNFalpha.

The modulatory effects of IL-1beta and TNF alpha on the rat paw edema induced by B1 agonists have been analyzed. In naive rats, i.d. injection of B1 agonists, des-Arg9-bradykinin and des-Arg10-kallidin (up to 300 nmol), causes a minimal increase in paw volume, while the B2 agonist tyrosine8-bradykinin (0.3-10 nmol) induces graded paw edema. The injection of des-Arg9-bradykinin (10-100) nmol or des-Arg10-kallidin (1-100 nmol), in paws pre-treated with IL-1beta or TNF alpha (both 5 ng/paw; 60 and 30 min prior, respectively), caused a graded edema formation. The edemas induced by des-Arg9-bradykinin (100 nmol) were evident at 15 min, reaching the maximum 60 and 30 min after treatment with IL-1beta (0.64 +/- 0.06 ml) or TNF alpha (0.47 +/- 0.05 ml), respectively, being reduced at 360 min. The B1 antagonist des-Arg9-NPC 17731 (1-30 nmol), but not the B2 antagonist Hoe 140 (10 nmol), produced marked inhibition of des-Arg9-bradykinin-induced paw edema. Dexamethasone (0.5 mg/kg, s.c., 4 h) or cycloheximide (1.5 mg/kg, s.c., 6 h) significantly prevented the edema caused by des-Arg9-bradykinin (100 nmol) in rats treated with IL-1beta (81 +/- 5% and 59 +/- 3%) or TNF alpha (78 +/- 4% and 43 +/- 2%). Indomethacin (2 mg/kg, i.p.) or meloxicam (3 mg/kg, i.p.), 1 h prior, significantly reduced the edema induced by des-Arg9-bradykinin (100 nmol) in IL-1beta (40 +/- 6% and 69 +/- 8%) or TNF alpha (43 +/- 3% and 53 +/- 9%) treated rats. It is suggested that i.d. injection of the IL-1beta or TNF alpha, produced up-regulation of B1 receptor-mediated paw edema, being this effect sensitive to dexamethasone and cycloheximide and to cyclo-oxygenase pathway.

Animals↗

Clinical implications of natural killer cytotoxicity in patients with squamous cell carcinoma of the penis.

Impairment of natural cytotoxicity mediated by natural killer (NK) cells may play a role in the pathogenesis of penile carcinoma. The aim of this study was to examine the NK activity profile and its prognostic significance in patients with squamous cell carcinoma of the penis. The NK activity was measured in peripheral blood mononuclear cells (PBMCs) from 39 patients diagnosed histologically as having invasive squamous cell penile carcinoma and 4 patients with verrucous carcinoma of the penis. Of 39 patients with invasive squamous cell carcinoma, 4 had undergone previous penile amputation. According to the prognosis, the patients with invasive squamous cell carcinoma were divided into two groups: with metastasis and without metastasis. The patients were evaluated in relation to clinicopathologic variables using univariate analyses. NK cell activity was significantly decreased in all patients with penile carcinoma when compared with the control groups (p < 0.0001). There was no statistically significant difference between the groups with and without metastasis. We conclude that there is a decrease in NK activity in PBMCs from patients with penile carcinoma and that the presence of advanced disease or metastatic involvement is not responsible for this reduction.

Adult↗

Anti-allergic effects and oedema inhibition caused by the extract of Drymis winteri.

OBJECTIVE: To study the acute anti-inflammatory and anti-allergic properties of an extract of D. winteri. MATERIAL AND METHODS: Paw oedema induced in rats with various stimuli and anaphylactic shock in mice. RESULTS: The hydroalcoholic extract (HE) of D. winteri (Winteraceae) (30 to 100 mg/kg, p.o., 1 h prior) inhibited carrageenan (300 micrograms/paw) and dextran (100 micrograms/paw)-induced paw oedema formation in a dose-dependent manner, with mean ID50 values of 49 and < 30 mg/kg, respectively. The HE of D. winteri (30 to 100 mg/kg) also inhibited paw oedema induced by bradykinin (BK) (3 nmol), substance P (SP) (10 nmol) and PAF-acether (PAF) (10 nmol), in a dose-dependent manner, with mean ID50 values of 56, 63, and 58 mg/kg, respectively. However, the HE inhibited the rat paw oedema induced by prostaglandin E2 (PGE2) (10 nmol) (29 +/- 7 and 33 +/- 2% at 60 and 240 min) to a smaller extent, and had no effect on oedema elicited by histamine (100 nmol). In adrenalectomized animals, the inhibition by the HE of D. winteri (100 mg/kg, p.o., 1 h prior) of BK-elicited oedema (3 nmol/paw) was significantly smaller when compared with that observed in control animals. When assessed in rats actively sensitised to ovalbumin (OVO), the oedema caused by OVO (6 micrograms/paw) was significantly inhibited by HE of D. winteri (30 to 100 mg/kg, p.o.), with a mean ID50 of about 65 mg/kg. The HE of D. winteri (100 and 200 mg/kg, p.o.) significantly increased survival rate when assessed in anaphylactic shock in mice actively sensitised to the antigen. The protective effect was long-lasting, being observed for up to 15 h. Dexamethasone, used as positive control (0.5, 1 and 2 mg/kg) produced a long-lasting (up to 24 h) increase in the survival rate of the animals. CONCLUSIONS: These results confirm and extend our previous studies, and demonstrate the clear oral anti-inflammatory and anti-allergic properties of the active principle(s) present in the barks of D. winteri, thus confirming its reported medicinal use in folk medicine for the management of airway diseases.

Adrenalectomy↗

The role of B1 and B2 kinin receptors in oedema formation after long-term treatment with Mycobacterium bovis bacillus Calmette-Guérin (BCG).

1. The present study was designed to investigate the influence of long-term systemic treatment with Mycobacterium bovis bacillus Calmette-Guérin (BCG, 1 dose per animal, containing 6 x 10(4) colony-forming-units (CFu), 5 to 75 days beforehand) on oedema formation induced by intradermal injection of B1 and B2 selective agonists. The interaction between the B1 agonist des-Arg9-bradykinin and bradykinin was also investigated. 2. Intradermal injection (i.d.) of the B2 selective agonist tyrosine8-bradykinin (1-10 nmol) in naive (saline pretreated) animals, or in animals that had received BCG (30 days beforehand), caused dose-related and very similar oedema formation (ED50; 1.1 and 1.0 nmol/paw, respectively). I.d. injection of the selective B1 agonists des-Arg9-bradykinin (100 nmol) or des-Arg10-kallidin in naive animals caused very little paw oedema (0.04 +/- 0.06 and 0.07 +/- 0.02 ml, respectively, n = 5). However, i.d. injection of des-Arg9-bradykinin (10-300 nmol) or des-Arg10-kallidin (3-100 nmol) in animals pretreated with BCG, 30 days previously, resulted in dose-related and marked oedema formation, with mean ED50 values of 20.1 and 5.5 nmol/paw, respectively. 3. Oedema caused by i.d. injection of des-Arg9-bradykinin (100 nmol/paw) in rats pretreated with BCG was evident 5 days after treatment, reaching the maximum 30 days later, remaining stable for up to 45 days, and reduced markedly at 75 days. 4. The i.d. co-injection of the selective B1 antagonists des-Arg9[Leu8]-bradykinin (200 nmol), des-Arg10[Leu9]-bradykinin (30 nmol) and des-Arg9-NPC 17731 (30 nmol) significantly (18 +/- 3, 34 +/- 2 and 56 +/- 4%, respectively) prevented the paw oedema caused by i.d. injection of des-Arg9-bradykinin (100 nmol) in rats treated with BCG. These effects were selective, because the i.d. injection of the B1 selective antagonist des-Arg10[Leu9]-kallidin (30 nmol), at the same dose that consistently antagonized des-Arg9-bradykinin (100 nmol)-mediated paw oedema, had no significant effect against tyrosine8-bradykinin (3 nmol)-induced oedema in animals that had been treated previously with BCG. On the other hand, the i.d. co-injection of the selective B2 antagonist, Hoe 140 (10 nmol) at a dose which markedly inhibited tyrosine8-bradykinin (3 nmol)-induced oedema by 55 +/- 4%, did not significantly affect des-Arg9-bradykinin-induced paw oedema in animals pretreated with BCG. 5. Treatment of animals with dexamethasone (0.5 mg kg-1, s.c.) every 24 h, from day 0 to day 30, inhibited significantly (67 +/- 4%) the oedema caused by des-Arg9-bradykinin (100 nmol), but did not affect the paw oedema caused by tyrosine8-bradykinin (3 nmol) in animals pretreated with BCG. 6. Indomethacin (2 mg kg-1, i.p.), administered 1 h before experiments, significantly inhibited des-Arg9-bradykinin (100 nmol)-induced oedema formation, and, to a lesser extent, the paw oedema caused by tyrosine8-bradykinin (3 nmol) (44 +/- 4 and 20 +/- 4%, respectively). 7. These findings show that the long-term systemic treatment of rats with BCG promoted a time-dependent and consistent paw oedema formation to B1 agonists, des-Arg9-bradykinin and des-Arg10-kallidin, leaving responses to the B2 agonist tyrosine8-bradykinin unaffected. The upregulation of B1 receptors after BCG treatment was inhibited by dexamethasone, suggesting the possible involvement of de novo protein synthesis. Finally, our results also show that in BCG-treated animals, the B1 agonist des-Arg9-bradykinin interacts in a synergistic manner with bradykinin. Therefore, both B1 and B2 kinin receptors appear to play a relevant role in modulating chronic inflammatory processes.

Animals↗

Upregulation of B1 receptor mediating des-Arg9-BK-induced rat paw oedema by systemic treatment with bacterial endotoxin.

1. The effect of pretreatment with bacterial endotoxin (LPS, 10 micrograms, i.v., 24 h) on the bradykinin B1 and B2 receptor-induced oedema in the rat paw, and the interaction of B1-mediated responses with other inflammatory mediators, was investigated. 2. Intraplantar (i.pl.) injection of the selective B1 agonist, des-Arg9-BK (DABK, 100 nmol) in naive animals pretreated with the angiotensin converting enzyme inhibitor, captopril caused a small increase in paw volume (0.04 +/- 0.003 ml, mean +/- s.e. mean, n = 6), while the B2-selective agonist, tyrosine8-bradykinin (T-BK, 3 nmol) induced marked oedema (0.36 +/- 0.02 ml). However, i.pl. injection of DABK (3-300 nmol) in rats pretreated with LPS (24 h beforehand) resulted in a marked dose- and time-related increase in paw volume, with mean ED50 of 24.1 nmol. In contrast, oedema caused by T-BK (3 nmol) was reduced by 79 +/- 4% in animals treated with LPS when compared with naive animals. 3. Oedema caused by prostaglandin E2 (PGE2, 10 nmol) was unaffected by LPS treatment, while oedema induced by histamine (100 nmol), 5-hydroxytryptamine (5-HT, 10 nmol) and substance P (SP, 3 nmol) was reduced (P < 0.05). 4. The selective B1 antagonist, des-Arg9[Leu8]-BK (100-300 nmol), produced dose-dependent inhibition of DABK (100 nmol)-induced paw oedema in LPS-treated animals with mean IC50 of 134 nmol, while the selective B2 antagonists, Hoe 140 and NPC 17731 (each 10 nmol), had no effect. 5. Treatment of animals with dexamethasone (0.5 mg kg-1, s.c.) 24 or 48 h prior to LPS injection resulted in a graded inhibition of DABK (100 nmol)-induced oedema formation (58 +/- 3 and 82 +/- 2%, respectively), and almost reversed to control value oedema formation induced by T-BK (3 nmol) in LPS-pretreated rats. Cycloheximide (1 mg kg-1, s.c.) or indomethacin (2 mg kg-1, i.p.) pretreatment 24 and 1 h prior to LPS injection, respectively, markedly inhibited DABK (100 nmol)-induced paw oedema (98 +/- 2 and 50 +/- 4%, respectively). 6. Intraplantar injection of submaximal dose of DABK (10 nmol) in LPS-treated rats produced modest paw oedema (0.09 +/- 0.03 ml). However, i.pl. injections of PGE2, prostacyclin (PGI2), calcitonin-gene-related peptide (CGRP), SP, 5-HT, or platelet activating factor (PAF) (each 1 nmol), which alone caused little or no paw oedema, resulted in a potentiation of the DABK-induced oedema. The increases in paw volume (in ml) were: PGE2 + DABK (0.31 +/- 0.03), PGI2 + DABK (0.39 +/- 0.02), CGRP+DABK (0.35 +/- 0.04), DABK+SP (0.33 +/- 0.04), DABK + 5-HT (0.40 +/- 0.02) and DABK+PAF (0.38 +/- 0.016) ml. In contrast, histamine (1 nmol) was ineffective in potentiating the response to DABK. 7. The selective B1 receptor antagonist, DALBK (100-300 nmol), produced dose-dependent inhibition of paw oedema potentiation induced by co-injection of DABK and other mediators with mean ID50S (nmol) of: 180, 160, 139 and 135 in the presence of PGE2, PGI2, SP and 5-HT, respectively. 8. These results demonstrate that DABK-induced increase in paw volume in LPS-treated rats is probably mediated by induction of B1 receptors, associated with downregulation of B2 receptors. The induction of B1 receptors by LPS is sensitive to dexamethasone and cycloheximide treatment and requires activation of cyclo-oxygenase pathway. In addition, B1 receptors, when upregulated following LPS treatment, can interact in a synergistic manner with several inflammatory mediators such as PGI2, PGE2, CGRP, PAF and 5-HT. Such results indicate that induction of the B1 receptor might have a significant pathophysiological role in modulating chronic inflammatory diseases.

Animals↗

Inhibition of human LAK-cell activity by the anti-depressant trifluoperazine.

The anti-depressive drug trifluoperazine (TFP) was studied on in vitro immune responses. TFP proved to be an inhibitor of lymphokine-activated killer (LAK) cells in its generative step, as well as in its effector phase. Natural killer (NK) activity and interleukin-2 (IL-2) or mitogen-induced lymphocyte proliferation were just as sensitive to the drug effects, whereas the division of tumor cells was more resistant. The mechanism through which TFP suppresses these lymphocytic systems remains unclear. It does not, however, affect an early stage of cellular activation as the addition of the drug as late as 24 h after the start of the culture was still inhibitory for lymphocyte mitogenesis. Neither the expression of CD25, nor that of CD56 was affected by TFP, and exogenous IL-2 was unable to overcome the suppression of proliferation. In relation to cell-mediated cytotoxicity, TFP partially interfered with the effector/target binding. However, addition of lectin to the assay did not overcome the inhibition of lysis produced by the drug. Although further work remains to be done, the effect of TFP on immune responses must be taken into consideration when treating immunosuppressed patients.

Antigens, Differentiation, T-Lymphocyte↗

Involvement of B1 and B2 receptors in bradykinin-induced rat paw oedema.

1. The mechanisms involved in bradykinin (BK)-induced oedema in the rat paw as well as the interactions between BK and several inflammatory mediators, have been investigated. 2. Intraplantar injection of BK (1 nmol/paw) in rats pretreated with captopril (5 mg kg-1, s.c.) caused a small amount of oedema formation (0.17 +/- 0.05 ml). Des-Arg9-BK (DABK, a selective B1 receptor agonist) up to 300 nmol/paw caused minimal oedema (0.03 +/- 0.01 ml). 3. Co-administration of prostaglandin E2 (PGE2), prostaglandin I2 (PGI2), calcitonin gene-related peptide (CGRP), 5-hydroxytryptamine (5-HT), substance P (SP) or platelet activating factor (PAF) (1 pmol-1 nmol/paw) with BK (1 nmol/paw) dose-dependently potentiated BK-induced paw oedema. The rank order of potency (mean ED50, pmol/paw) for this effect was: SP (8.1) > PAF (13.7) > PGI2 (20.5) > 5-HT (23.8) > CGRP (25.7) > PGE2 (52.0). Co-administration of BK with the various inflammatory mediators resulted in maximal paw oedemas (ml) of: PGE2 (0.71 +/- 0.02); PGI2 (0.66 +/- 0.02); 5-HT (0.65 +/- 0.01); SP (0.63 +/- 0.05); CGRP (0.60 +/- 0.05) and PAF (0.47 +/- 0.02) ml. Histamine (up to 1 nmol/paw) was ineffective in potentiating the response to BK. 4. Hoe 140 or NPC 17731 (two selective B2 receptor antagonists, 0.1-3 nmol/paw) produced dose-dependent inhibition of paw oedema potentiation induced by co-injection of BK with other mediators with the following mean ID50s (nmol/paw): Hoe 140-1.4; 1.3; 1.5 and 1.1 and NPC 17731-1.0; 1.0; 0.9 and 0.7; in the presence of PGE2, PGI2, CGRP and SP, respectively. The selective B1 receptor antagonist des-Arg9 [Leu8]-BK (DALBK, up to 300 nmol/paw) had no effect.5. Daily intraplantar injections of BK (10 nmol/paw) once a day for 7 consecutive days caused a progressive and complete desensitization of the paw oedema, which was specific for BK, since paw oedema induced by PAF, PGE2, SP or histamine was not affected. In addition, the oedema caused by BK in the paw desensitized to the peptide was almost completely reversed if BK was co-injected with PGE2, PGI2 or SP (1 nmol/paw). Injection of PGE2 or SP (10 nmol/paw) together with the first BK injection (1O nmol/paw), partially prevented BK-induced desensitization.6. When animals were completely desensitized to BK, DABK (100nmol/paw) caused paw oedema(0.25 +/- 0.03 ml) which was consistently blocked by the B1 receptor antagonist, DALBK (100 nmol/paw).7. Treatment of animals with dexamethasone (0.5 mg kg-1, s.c., 24 h previously) antagonized paw oedema induced by DABK (100 nmol/paw) in desensitized paws, but not that induced by BK (3 nmol/paw) in naive paws. The steroid also prevented the recovery of oedema seen after co-injection of BK with PGE2 or PGI2 (1 nmol/paw) in desensitized paws.8. These results suggest that both B, and B2 receptors are involved in BK-induced rat paw oedema. The B2 receptors are constitutive, but induction of expression of B, receptors seems to occur only after complete desensitization of the paw to BK. In addition, very low doses of inflammatory mediators markedly potentiate BK-induced paw oedema and can attenuate BK-induced paw oedema desensitization.Such mechanisms may be relevant for the manifestation of acute and chronic inflammatory processes.

Animals↗

Expression of B1 kinin receptors mediating paw edema and formalin-induced nociception. Modulation by glucocorticoids.

Bradykinin (BK) and Tyr8-BK induced graded rat paw edema with EC50 values of 1.9 and 1.1 nmol/paw, while des-Arg9-BK (DABK, up to 300 nmol/paw) was marginally effective. Tyr8-BK, but not DABK, also caused a dose-related increase in mouse paw edema, with an EC50 of 1.3 nmol/paw. The response to Tyr8-BK (10 nmol/paw) in rat paw edema was antagonized by B2 receptor antagonists (HOE-140 or NPC 17731, 30 nmol/paw) but not by the B1 antagonist des-Arg9[Leu8]BK (DALBK, 100 nmol/paw). Daily intraplantar injections of Tyr8-BK (10 nmol/paw) for 7 days caused progressive desensitization (D) of edema in sham-operated and adrenalectomized Wistar rats. DABK (100 nmol/paw) caused marked paw edema in D paws from both groups, which was inhibited by DALBK (100 nmol/paw) and by dexamethasone (0.5mg/kg, s.c.). Systemic injection of lipopolysaccharide (10 micrograms/mouse, 24 h prior) potentiated the first and second phases of Formalin-induced pain but had no effect on paw edema. Coinjection of DABK (2-22 nmol/paw) with low doses of Formalin in lipopolysaccharide-treated mice, which had no effect on naive animals, dose dependently potentiated both phases of Formalin-induced pain but did not modify paw edema. These effects were antagonized by DALBK with ID50 values of 21.9 (first phase) and 64.1 (second phase) nmol/paw. Thus, both progressive desensitization of B2 receptors and systemic treatment with lipopolysaccharide induce a glucocorticoid-sensitive upregulation of B1 receptors mediating paw edema in the rat and Formalin-induced nociception in mice. These results suggest that induction of upregulation of B1 receptors may play important roles in controlling inflammatory processes and hyperalgesia.

Animals↗

Effect of ouabain on lymphokine-activated killer cells.

A large amount of evidence points towards the potential role of lymphokine activated killer (LAK) cells as tools in the treatment of chronically stressed conditions, such as cancer. The modulation of this activity by biologically active endogenous compounds of the HPA (hypothalamic-pituitary-adrenal) axis, however, is not completely understood. Ouabain, a specific inhibitor of Na(+)-K(+)-ATPase, and now recognized as an endogenous component present in human plasma, was tested on IL-2 and TPA-activated killer cells. Ouabain was able to inhibit the generation of LAK activity, as well as to suppress either PHA or TPA-induced lymphocyte proliferation. Once the cells were triggered for cytotoxicity, however, ouabain was not able to interfere with their effector phase, as it did not show any effect when present only during the assay. TPA-induced "LAK-simile" cells displayed the same sensitivity towards ouabain as LAK cells did. Although the physiological relevance of endogenous ouabain secretion remains elusive, these effects of ouabain on LAK cytotoxicity should be considered in patients undergoing this kind of immunotherapy.

Cytotoxicity, Immunologic↗

Immunological recovery after bone marrow transplantation for severe aplastic anaemia: a Brazilian experience.

Twenty-nine patients with severe aplastic anaemia (SAA) were submitted to bone marrow transplantation (BMT) and their immunological recovery analysed. Total lymphocyte counts, estimation of B lymphocytes, T lymphocytes and their subsets, natural-killer (NK) activity were performed. Cells with the CD8+ phenotype and NK activity were the first signs of immunological recovery, whereas the CD4+ subset recovered later in patients who suffered from acute graft versus host disease (GvHD) and infections. Acute and chronic GvHD, cirrhosis, rejection and HIV viral infection contributed to the persistence of the profound immunodeficiency status observed after BMT. Our results did not differ greatly from the others and confirmed that BMT may be performed in underdeveloped countries despite the difficulties it might pose.

Adult↗

Analgesic effects of callus culture extracts from selected species of Phyllanthus in mice.

The aim of this study was to evaluate the analgesic effect of the methanolic extract from callus culture of Phyllanthus tenellus, P. corcovadensis and P. niruri in several models of pain in mice. The extracts (medium containing 2,4-dichlorophenoxyacetic acid) of P. corcovadensis, P. niruri and P. tenellus (3-90 mg kg-1, i.p.) caused graded inhibition of abdominal constrictions induced by acetic acid (0.6%), with ID50 (i.e. dose that reduced response of control by 50%) values of about 30, 19 and > 30 mg kg-1, respectively. The extract of callus of Phyllanthus obtained in indole-3-butyric acid and indole-3-acetic acid media (3-90 mg kg-1, i.p.) caused a similar analgesic effect. In the formalin test, the extract of P. tenellus obtained in indole butyric acid medium (3-100 mg kg-1, i.p.) inhibited only the second phase of formalin-induced pain with an ID50 value of about 100 mg kg-1. Both the indole acetic acid and indole butyric acid methanolic extracts of P. tenellus and P. corcovadensis (10-100 mg kg-1, i.p.) dose-dependently inhibited both phases of formalin-induced pain (ID50 values for the second phase were approx. 100 and 52 mg kg-1, respectively). However, the extract of callus from Phyllanthus failed to affect formalin-induced paw oedema, as well as the response to radiant heat in the tail-flick test. In addition, the analgesic effect of morphine, but not the analgesic effects caused by Phyllanthus callus extract, was fully antagonized by naloxone.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdominal Muscles↗

Antivenom and biological effects of ar-turmerone isolated from Curcuma longa (Zingiberaceae)

A potent antivenom against snakebite was isolated from Curcuma longa, a plant commonly used in traditional Brazilian medicine. The fraction consisting of ar-turmerone neutralized both the hemorrhagic activity present in Bothrops jararaca venom, and the lethal effect of Crotalus durissus terrificus venom in mice. Immunological studies demonstrated that this fraction also inhibited the proliferation and the natural killer activity of human lymphocytes.

Animals↗

Effect of canatoxin on cell cultures.

Canatoxin, a toxic protein isolated from Canavalia ensiformis, was shown to inhibit DNA synthesis and to produce a cytolytic effect when added in vitro to various cells, in doses ranging from 50 to 500 nM. In this case no selectivity was found for a certain cell type, as both normal and transformed cells could be affected by the toxic protein. The cytostatic effect was irreversible upon removal of the toxic protein from the medium and could be fully attained after exposing the cells to canatoxin for only 30 min. The use of an in vitro cell culture system may allow for a better insight on the mode of action of canatoxin.

Animals↗

[Colitis caused by cytomegalovirus in acquired immunodeficiency syndrome. Report of 2 cases of autopsy].

Two autopsy cases of CMV colitis in AIDS are reported. Intestinal manifestations lasted 2 and 5 months in each case and included: diarrhea and abdominal colic pain. The causes of death were: disseminated CMV infection in case 1 and miliary tuberculosis in case 2. In case 1 small ulcers were apparent in the ileum and the cecum. Microscopic foci of necrosis were also observed. Case showed: sigmoid dilatation with mucosal hemorrhages, small acute ulcers and submucosal fibrosis in the transverse portion of the colon. In both cases cytomegalic inclusion bodies within the endothelial cells of the capillaries at the bottom and the margin of the ulcers were observed. We compare our findings with those in other recently published cases.

Acquired Immunodeficiency Syndrome↗