[Case report: Muir-Torre syndrome diagnosed from a sebaceoma mimicking an ulcerated breast cancer]. / Syndrome de Muir-Torre. À propos d'un cas diagnostiqué suite à l'apparition d'un sébacéome mimant un cancer ulcéré du sein gauche.

On the basis of a case report, we conducted a search through the literature concerning Muir-Torre syndrome. This syndrome is considered to be a phenotypic variant of Lynch syndrome (or Human Non Polyposis Colorectal Cancer). Muir-Torre syndrome is a familial cancer syndrome defined as the association of an internal malignancy with cutaneous sebaceous tumors. It is a rare disease. In our knowledge, this case is the first reported skin lesion related to Muir-Torre syndrome, located on the breast and mimicking ulcerated breast cancer. Genetic counselling obviously has an important place in the management of this pathology.

Enhanced secretion of heterologous cyclodextrin glycosyltransferase by a mutant of Bacillus licheniformis defective in the D-alanylation of teichoic acids.

AIMS: To examine whether inactivation of the dlt operon and increased charge density of the wall enhances secretion of heterologous proteins in industrial strains of Bacillus licheniformis. METHODS AND RESULTS: The dltA gene of B. licheniformis was cloned, sequenced and mutated by inserting a chloramphenicol acetyl transferase (cat) gene cassette. The mutation facilitated growth in the late exponential growth phase, increased endogenous autolysis and decreased resistance to a cationic peptide, polylysine. It was observed that dltA mutation increased the production of cyclodextrin glycosyltransferase (CGTase) by 1.5- to sevenfold depending on the growth phase, but decreased the production of penicillinase by twofold. CONCLUSIONS AND SIGNIFICANCE: The results suggest that the d-alanylation of teichoic acids is an element that can be used to improve the production of some secretory proteins in industrial applications based on this important industrial microorganism.

Stability of plasmid pHV1431 in free and immobilized cell cultures. Effect of temperature.

The segregational and structural stability of pHV1431 has been examined in Bacillus subtilis grown at 30 and 37 degrees C in continuous cultures without selection pressure. Immediately after appearance of plasmid-free cells in the reactor, a competition was observed between bacteria that favored plasmid-free cells because of the faster growth. A stronger instability was found at 30 degrees C compared to that at 37 degrees C. At 30 degrees C after 50 hours of culture, 2% of the cells carried the plasmid, whereas at 37 degrees C this percentage was reached after 130 hours. In both cases, no structural instability was observed. To improve the stability, the recombinant Bacillus subtilis (pHV1431) was immobilized in kappa-carrageenan gel beads. In comparison to free cell systems, a higher cell concentration was obtained. Moreover, the plasmid was maintained stable for longer periods; after 150 hours of culture 40% of cells in the reactor still carried the plasmid at both temperatures.

Improvement of plasmid stability of recombinant Bacillus-subtilis cells in continuous immobilized cultures.

The immobilization of recombinant Bacillus subtilis in K-carrageenan gel beads has been performed in order to study the growth conditions inside the gel beads and to improve plasmid stability. Bacterial colonies showing high cell density were studied using scanning electron microscopy. A series of continuous cultures of free and immobilized B. subtilis MT119 (pHV1431, pIL252 and pIL252 Kpn) have been developed without selection pressure. In the free-cell systems, it was found that a loss of plasmid vectors occurred after a short period. In contrast, in the immobilized cell systems, plasmid-free segregants were not detected in any of the cases during the first 80 h of the culture.

Response of human and rat small intestinal mucosa to oral administration of Saccharomyces boulardii.

To evaluate the response of the small intestinal mucosa to Saccharomyces boulardii (S.b.), a yeast widely used in some countries as an adjuvant drug with oral antimicrobial therapy, seven healthy adult volunteers were treated with high doses of lyophilized S.b. (250 mg four times per day) for 2 wk. A peroral jejunal suction biopsy was performed on days 0 and 15 of the study. Compared to the initial biopsy, histological examination of the posttrial biopsy revealed no morphological alteration nor change in villus height or crypt depth. After treatment, the specific activity (per U protein) of sucrase, lactase, and maltase was, respectively, increased by 82% (p less than 0.05) 77% (p less than 0.05), and 75% (p less than 0.05) over the basal activity of the enzymes measured on day 0, whereas mucosal protein content remained unchanged. Similar findings were found in the jejunum of adult rats treated for 5 days with either viable or killed S.b. cells. The changes in total enzyme activity (per jejunal segment) paralleled the changes in specific enzyme activity. In vitro assays on freshly prepared suspensions of S.b. (6.0 X 10(8) viable cells/ml) evidenced a high activity for sucrase (mean +/- SE: 8 364 +/- 1280 U X g X protein-1) but no maltase, neutral lactase, acid beta-galactosidase, or aminopeptidase activity. To determine whether treatment with S.b. could influence the incorporation rate of neutral lactase into the brush border membrane, 14-day-old sucklings treated either with saline or with S.b. were given intraperitoneally a dose of 20 microCi D-[1(14)C] glucosamine 3 hours before sacrifice.(ABSTRACT TRUNCATED AT 250 WORDS)

Role of dietary iron in maturation of rat small intestine at weaning.

The weanling process is characterized by the transition from a liquid diet poor in iron (rat milk) to a solid diet high in iron (chow pellets). To examine the effects of iron content of the weanling diet on terminal maturation of rat small intestine, suckling pups, nursed by iron-sufficient mothers, were weaned by day 16 onto a solid basal diet that was either deficient [low-iron diet (LID): 0.5 mg iron/100 g solid] or high [high-iron diet (HID) controls: 30 mg iron/100 g solid] in iron. The animals were studied during or at the end of the 4th postnatal wk. By day 17 rats weaned onto the LID exhibited an initial rise in jejunal sucrase activity as did their controls, but the activity plateau of the enzyme was reduced to a level 60% of the controls. On day 28 iron-deprived rats were anemic and showed significant decreases (P less than 0.01 compared with HID rats) in the activity of jejunal sucrase (-57%), neutral lactase (-83%), and maltase (-46%), whereas villus height, crypt depth, mucosal mass parameters, ileal acid beta-galactosidase activity, mucosal protein, and DNA synthesis rates were equivalent in LID and HID groups. The concentration of the secretory component, a glycoprotein synthesized by the intestinal crypt cell, was markedly depressed (P less than 0.01 vs. controls) in the jejunum (-54%) and ileum (-79%) of iron-deprived rats. When D-[1-14C]glucosamine was injected intraperitoneally, incorporation of the label into jejunal and ileal brush-border proteins was two to three times lower for iron-deficient rats than for controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptive response of growing rat small intestine to acute Adriamycin injury.

The response of the intestinal mucosa to Adriamycin (ADR) was studied in the duodenum, jejunum, and ileum of 25-day-old rats. A single injection of ADR resulted in decreases in mucosal DNA per centimeter of length and in sucrase activity, which were proportional to the doses given (2, 5, and 8 mg/kg). ADR at 2 mg/kg had no significant effect on body weight, gut length, epithelial structure, or mucosal protein content per unit length. The morphological modifications occurred mostly in the proximal intestine and consisted of villous atrophy and degenerative changes of villus and crypt cells. A single dose of 5 mg ADR/kg acutely affected the gut. At 48 and 96 h the changes were characterized by marked decreases in mucosal weight, DNA per centimeter, sucrase activity, and villous shortening. At 144 h, the ADR-treated intestine entered a highly proliferative state and showed increased villous height, mucosal weight, and DNA per centimeter. Although villous hyperplasia was observed at 144 and 192 h, the mucosal weight and DNA concentrations did not exceed the corresponding levels in the control. During the period of active epithelial proliferation, sucrase activity remained depressed. We conclude that in the growing rat: (a) the acute intestinal injury of ADR is short-lived, dose dependent, and predominates in the proximal small intestine; (b) the enteric mucosa reacts to cytotoxic injury by excessive proliferation of immature enterocytes; and (c) the hyperplastic response to ADR is confined to the mucosal epithelium.

Direct influence of the three natural estrogens on human mammary gland in vitro.

The direct influence of the three basic natural estrogens, estrone, 17 beta-estradiol and estriol, on DNA synthesis in human normal mammary epithelial cells was investigated in organ culture during 7 days, and was assessed by autoradiography. A threshold concentration of I.O. ng per ml was needed to elicit a significant stimulation by estradiol and estriol. No significant increase in the incorporation of tritiated-thymidine could be obtained with estrone in the same conditions. These observations are in keeping with the hypothesis put forward by Gurpide, Tseng and Gusberg (1977) that estrone per se might be devoid of any direct estrogenic effect.

Diaminobenzidine histochemistry in light microscopy.

Basically the DAB-technique localizes 3 enzymes, i.e. peroxidase, catalase, and cytochrome oxidase, but also pseudoperoxidatic activity of hemeenzymes (hemoglobin, myoglobin, etc.). Although at the ultrastructural level, i.e. in cytochemistry, the appropriate conditions for specific identification of each of these enzymatic activities have been extensively studied and reported in the literature, the subject remains open to investigation. In light microscopy DAB staining has been less thoroughly studied. Since DAB histochemistry might have practical interest in daily diagnostic pathology, it appeared worthwhile to work out a method convenient for paraffin embedded tissues. The method consisted of a prolonged incubation 48 h) of small tissue blocks, which had been prefixed for 1 h in 4% formaldehyde. Dehydration and rehydration occurred in graded ethanols; counterstain was obtained by toluidine blue. Although further experiments are needed to specify the physico-chemical conditions for the three enzymatic activities, the results are morphologically superior to that of frozen sections.

[Choledochus cyst: a case with dilatation of the intrahepatic bile ducts and congenital liver fibrosis]. / Kyste du cholédoque: un cas avec dilatation des voies biliaires intrahépatiques et fibrose hépatique congénitale.

The authors report the case of a 2-year-old girl with hepatomegaly and failure to thrive in whom the diagnosis of congenital hepatic fibrosis was first considered on the basis of the histological examination of a percutaneous liver biopsy. Further radiographic and ultrasonic investigations of the biliary tree showed a choledocal cyst and dilatation of the intrahepatic ducts. Surgical operation consisted in complete removal of the cyst with hepaticojejunostomy. The congenital intrahepatic abnormalities associated with the choledochal cyst are commented.

Estriol-induced dose-dependent DNA synthesis in normal human mammary epithelium in vitro.

Normal human adult resting mammary gland explants were cultured during 7 days. The influence of hormones on DNA synthesis was assessed by autoradiography after incubation with tritiated-thymidine. Estriol was added to the medium at 3 different concentrations. With 0.01 ng/ml the labeling index remained at the level observed in the controls in the basic unenriched medium. A 10- and 100-fold increase of estriol elicited a transient, significant and dose-related increase of DNA synthesis on the 2nd day of organ culture. Estriol gave a qualitatively different profile of DNA synthesis than estradiol at 1.0 ng/ml. The results are compared with the effect of progesterone.

Difficulties involved in diaminobenzidine histochemistry of endogenous peroxidase.

Basically peroxidase (PO) histochemistry is used in different areas: haematologic physiopathology, estrogen-dependent genito-mammary physiopathology and immunoperoxidase histochemistry, both in electron microscopic cytochemistry and at the light microscopic level. In immunochemistry, endogenous peroxidatic activity is inhibited by means of various procedures. On the contrary, in haematology and in reproduction biology stainability of endogenous PO is mandatory; controls are achieved using different inhibitors. Literature data on the most appropriated technical conditions concerning fixation, processing and incubation, for PO staining are reviewed.