Caspase-independent apoptosis in infected macrophages triggered by sulforaphane via Nrf2/p38 signaling pathways

Mycobacterium abscessus (Mabs), a non-tuberculous mycobacterium, is an emerging and rapidly growing opportunistic pathogen that is frequently found in patients with cystic fibrosis and in immunosuppressed patients. Its high tolerance to antibiotics is of great concern for public health. In this study, our results showed that human THP-1-derived macrophages infected with M. abscessus presented an increase in ROS production and cell necrosis. In addition, M. abscessus infection triggered activation of the Nuclear factor E2-related factor 2 (Nrf2) signaling pathway, and the induction of HO-1 and NQO1 expression levels. Interestingly, pretreatment of macrophages with sulforaphane (SFN), an activator of the antioxidant key regulator Nrf2, followed by M. abscessus infection significantly decreased mycobacterial burden. We demonstrated that this reduction in mycobacterial growth was due to an activation in cell apoptosis in SFN-pretreated and M. abscessus-infected macrophages. Pretreatment with specific MAPK inhibitors, PD98059, SP600125, and SB203580 to ERK, JNK, and p38 respectively, failed to inhibit induction of Nrf2 expression, suggesting that Nrf2 signaling pathway was upstream of MAPK signaling. Activation of cell apoptosis was caspase 3/7 independent but p38 MAPK dependent. Moreover, p38 MAPK induction was abolished in macrophages transfected with Nrf2 siRNA. In addition, p38 inhibitor abolished Nrf2-dependent apoptosis in infected macrophages. Taken together, our results indicate that modulation of the Nrf2 signaling using Nrf2 activators may help potentiate the actual drug therapies used to treat mycobacterial infection.

Phytosterols have an unfavourable effect on bacterial activity and no evident protective effect on colon carcinogenesis

The effects of physiological dietary phytosterol supplements on intestinal microflora activity and faecal sterols and their capacity to protect rats fed a normal or high saturated fatty-acid diet against tumour development were studied. A group of 80 female Wistar rats were fed an 8% lipid diet for 4 weeks (adaptation period) and then randomly assigned in a factorial experimental design study to diets containing 8% or 24% hydrogenated coconut oil, with or without a 24-mg/day/rat phytosterol supplement. They were instilled intrarectally with saline or methyl-nitroso-urea (MNU). Faecal sterol output was analysed for one week each month. Pathological analysis was done at the end of the 30-week experiment. Animals treated with MNU and given phytosterol supplements had tumour frequencies (8/20) similar to those not fed phytosterols (11/20). The fat-supplemented diet had no significant influence. Colonic glands were found in area of lymphoid follicles in all the groups, but were more frequent in rats on high-fat diets (P < 0.01). The coprostanol and the cholesterol excretion of the phytosterol-supplemented rats was significantly enhanced. Therefore phytosterols have an unfavourable effect on bacterial activity. These data confirm the capacity of phytosterols to decrease cholesterol absorption, but indicate that a large excess of phytosterol must be avoided until further research on its effects on carcinogenesis has been done.

Periesophageal mediastinal fibromatosis

We report two cases of aggressive fibromatosis of the mediastinum with esophageal involvement in adults. CT showed the posterior mediastinal mass involving the esophagus. In both cases, surgical resection was not feasible. Histopathologic examination showed a fibrous tissue. The patients died two years later.

Influence of a high-calcium carbonate diet on the incidence of experimental colon cancer in rats

This study was done to determine whether a high dietary calcium carbonate concentration could protect against colon tumors in rats. Female Wistar rats were randomly assigned to one of four groups and maintained on an 8% lipid diet for an adaptation period of four weeks. All groups were then fed a 24% lipid diet (sunflower oil), with (Groups 2 and 4) or without (Groups 1 and 3) a 1.5% calcium carbonate supplement. They were intrarectally instilled with saline (Groups 1 and 2) or nitrosomethylurea (NMU) (Groups 3 and 4). Fecal sterol output and pH were analyzed for one week each month. Histological analysis was done at the end of the 32-week experiment. No tumors were found in the non-NMU-treated animals. The NMU-treated rats had tumors: 31% in Group 3 and 30% in Group 4. The calcium carbonate supplement had no effect on this incidence. The lipid and cholesterol excretions of the calcium carbonate-supplemented rats were significantly enhanced. The coprostanol output was not altered, although its fecal concentration of the calcium-supplemented rats was decreased. Although neither lipid overload nor NMU treatment altered the fecal pH, it was significantly increased in both calcium carbonate-supplemented groups. These findings suggest that additional calcium as carbonate has no effect on colon tumor incidence, although the fecal composition is altered. The increased pH of the feces due to the carbonate could have the opposite effect to calcium.

[112 cases of sporadic and genetically determined pheochromocytoma: a comparative pathologic study]

The aim of this study was to compare 64 genetically determined pheochromocytomas (PH) (49 MEN IIa, 3 MEN IIb, 6 Von Recklinghausen diseases, 1 von Hippel-Lindau disease, 5 familial pheochromocytomas) and 48 sporadic PH. Genetically determined PH were more often observed among men and more frequently bilateral and multicentric than sporadic PH. Sporadic tumors had more often adrenal capsular invasion, necrosis and pseudocysts. Genetically determined PH were more differentiated with an insular pattern, hyaline globules and a higher percentage of polyhedric cells. Sporadic tumors were less differentiated with more frequently a diffuse pattern and small cells. Adrenal medullar hyperplasia was significantly associated with genetically determined PH. Adrenal cortical hyperplasia was not associated with a particular type of PH. The PS100 and chromogranin immunodetection was equivalent in both groups.

Gerstmann-Sträussler-Scheinker disease and the French-Alsatian A117V variant

Gerstmann-Sträussler-Scheinker disease is a rare familial form of prion disease. This autosomal dominant disorder is constantly associated with a point mutation on the PrP gene. Eight mutations affecting respectively codons 102, 105, 117, 145, 202, 212 and 218, have been so far described. Symptoms are variable and include ataxia and dementia. They generally appear between the fourth and sixth decade. Mean duration of the disease (5 years) is on the whole longer than that of other familial forms of prion diseases. Gerstmann-Sträussler-Scheinker disease is neuropathologically characterized by the presence of numerous multicentric or unicentric PrP amyloid deposits widespread throughout the encephalon. Spongiform change is inconstant. Neurofibrillary tangles have been described in some families. Clinicopathological features show considerable variability. Pathogenesis of amyloidosis and associated lesions as well as factors underlying the phenotypic polymorphism of the disease remain only partially known.

Medullary thyroid carcinoma: search for histological predictors of survival (109 proband cases analysis)

A group of 13 pathologists belonging to the French Calcitonin Tumor Study Group (GETC: Groupe d'Etude des Tumeurs à Calcitonine) examined the histological slides and medical records of 109 proband cases of medullary thyroid carcinoma (MTC) diagnosed on clinical features. The cases belonged to the various forms of the disease (80 sporadic and 29 familial MTC). The aim of the study was to detect histological predictors for survival by comparing morphological data from patients killed by the disease versus the others. Twenty-seven histological parameters were considered, including cellular heterogeneity, shape of the cells, and cytoplasmic characteristics. Other parameters such as sex, age, and phenotype of the disease were also studied. First, predictive parameters of interest on survival function were selected by univariate analysis (Mantel-Cox test). Then, the extracted parameters were tested in a multifactorial analysis using the Cox's forward stepping proportional hazard model. Five parameters were significantly associated with a lower survival function: presence of necrosis in the tumor (P = .001), squamous pattern (P = .002), age over 45 years (P = .004), presence of oxyphil cells in the tumor and absence of cells with intermediate cytoplasm (P = .025), less than 50% of calcitonin immunoreactive cells in the tumor (P = .04).

[Extra-cardiac rhabdomyoma of the fetal type]

Rhabdomyomas are benign tumors of striated muscle. They are distinguished by topographic data: cardiac or genital and by histological criteria: foetal or adult type. The foetal type is the most heterogeneous, with either a majority of immature cells or a mixture of maturing elements. This diversity has led to distinguish immature (or standard) foetal Rhabdomyomas from intermediate foetal Rhabdomyomas. One observation of this last type is reported. The authors highlight the essential characteristics of foetal Rhabdomyomas, however the exact meaning remains unclear: an anomaly in the differentiation of the striated muscle? or a true tumoral process through genetic anomaly?

Assessment of articular cartilage and subchondral bone: subtle and progressive changes in experimental osteoarthritis using 50 MHz echography in vitro

The main objectives of this work were to demonstrate the potential of 50 MHz echography for assessing initial and progressive morphological and structural changes of articular cartilage and bone developed in an experimental model of osteoarthritis (OA). Degenerative lesions were induced in rat knees by the unilateral intra-articular injection of a 3 mg dose of mono-iodo-acetic acid. To assess the lesion progression, the animals (n = 30) were sacrificed at different time intervals up to 8 weeks after the injection. Three-dimensional echographic data were acquired in vitro on patellar cartilage and bone at various stages of the remodeling process using a scanning ultrasound microscope. Changes involving the OA cartilage characteristics are discussed relative to those of the contralateral control joint which received a placebo. Images of control cartilage showed a smooth hyperechoic articular surface and an echoic matrix. The cartilage thickness was 266 +/- 44 microns (mean +/- SD) in the central region of the tissue. The precision of ultrasonic thickness measurements was better than 1.3%. First changes in cartilage internal structure and subchondral bone appeared on ultrasound images 3 days after the injection and were even more evident by day 7. They resulted in a slight thinning of the cartilage, a 30% increase of its internal structure echogenicity, and the appearance of echoic zones in subchondral bone. Histologic findings confirmed chondrocyte depletion and degeneration, decrease of matrix proteoglycans, and fibrovascular connective tissue proliferation at the subchondral plate. Progressive and severe lesions at both bone and cartilage surface and internal structure were assessed and correlated to histologic features. These results show that high resolution echography is sensitive to subtle and progressive osteochondral remodeling. This technique has the potential to be used for intra-articular quantitative imaging and assessment of early changes in bone and cartilage structure associated with natural human disease.

Gene alterations and apoptosis in rhabdomyosarcoma

The aim of the study is to look retrospectively for gene alterations and evaluate apoptosis in rhabdomyosarcomas (RMSs) from 40 children including 24 patients not previously treated. Histological subtype was botryoid in 1 case, spindle cell in 2 cases, embryonal in 22 cases, alveolar in 10 cases, and undetermined in 5 cases. Gene expression was evaluated immunohistochemically for p53 tumor suppressor gene, MDM2 oncogene, and bcl-2 gene. N-myc amplification was detected by in situ hybridization. Apoptotic cells and bodies were recognized morphologically and stained by 3-OH end labeling. Intranuclear accumulation of p53 protein was obvious (> 25% of tumor cells) in two recurrent embryonal RMSs. Expression of the MDM2 gene was intense (80% of tumor cells) in a recurrent and metastatic embryonal RMS. Amplification of the N-myc gene was obvious (about 20% of tumor cells) in an alveolar RMS metastatic at diagnosis. Expression of the bcl-2 gene was intermediate (25-75% of tumor cells) in 26% of cases and high (> 75% of tumor cells) in 10% of cases either embryonal or alveolar. The percentage of tumor cells showing morphologically recognizable apoptosis was 0.2-7.5% (mean 2.9%). There was no correlation between apoptosis and histological subtype, bcl-2 expression, or previous treatment.

Water-jet dissection in renal surgery: experimental study of a new device in the pig

The pig model was used for experiments with a new type of water-jet dissector, which produces high-pressure water by application of a gas and maintains the water fully sterile in a single-use delivery apparatus. The experiment was conducted ex vivo (14 kidneys) and in vivo to compare electric cautery section with water-jet dissection (5 vs 11 partial nephrectomies). Ex vivo study confirmed sparing of blood vessels and pelvicaliceal system. In vivo study did not show significant differences in blood loss but, the water-jet allowed precise dissection and tight closure of the excretory system. More frequent haemorrhages were noted on histological examination of the WJ group, but no coagulation necrosis. These are preliminary findings and further studies of long-term results may confirm the benefits of the absence of parenchymal necrosis and the definite advantage of precise closure of the pelvicaliceal system, as morbidity of partial nephrectomy is often related to secondary haemorrhages and urinary fistulae.

Clear cell rhabdomyosarcoma

A clear cell rhabdomyosarcoma was studied by light microscopy, histochemistry, immunohistochemistry, and electron microscopy. It was a large, painful left parapharyngeal mass in a 10-year-old boy with intracranial extension and cervical metastatic enlarged lymph nodes. Tumor tissue was macroscopically grayish. At microscopic examination, the architecture was diffuse and focally alveolar. Tumor cells were of three types. Most cells were large, round or polygonal, with abundant clear vacuolated cytoplasm. Fibrils were sometimes found to be present around the nucleus. Nuclei often had irregular outlines and multiple nucleoli. Mitotic activity was high. Some round or elongated cells had eosinophilic fibrillar cytoplasm and were found to have a few double striations. A few cells were round and medium sized with a high nucleocytoplasmic ratio. Periodic acid-Schiff stain demonstrated huge amounts of intracytoplasmic glycogen in clear cells. Tumor cells showed positive immunostaining for muscle markers (desmin, muscle actins, dystrophin). Electron microscopy showed large lakes of glycogen, lipid droplets, and striated muscle features.

Giant cell tumor of bone in children and adolescents

Giant cell tumor of bone rarely affects children, in whom it is usually located in a metaphysis in contrast to the predominantly epiphyseal localization in adults. Five cases are reported, two at the femur, two at the fibula and one at the tibia. Plain film radiography and computed tomography are the most informative imaging studies. The differential diagnosis is with aneurysmal bone cyst and, in metaphyseal-epiphyseal forms, with chondroblastoma. Treatment usually consists in curettage of the tumor followed by filling of the cavity; however, more extensive resection is required in some cases.

[Actinomycosis and non-Hodgkin's malignant lymphoma: fortuitous association?]

Two cases of actinomycosis associated with non Hodgkin's lymphoma (NHL) are reported. In one case, low grade NHL was diagnosed many years after actinomycosis because of the persistence of abdominal lymphadenopathy in spite of antibiotic therapy. In the second case, hepatic metastasis were initially suspected until actinomycosis diagnosis was made by percutaneous liver biopsy under scanography. High grade NHL was diagnosed by laparotomy and liver biopsy performed 6 weeks after the onset of antibiotic therapy as no improvement in hepatic lesions was obtained. These two case reports outline the difficulties encountered in the diagnosis of actinomycosis and the indication of a repeat biopsy when actinomycosis does not respond to antimicrobial therapy because of the possibility of concomitant malignancy.

Evaluation of the Duke criteria versus the Beth Israel criteria for the diagnosis of infective endocarditis

New diagnostic criteria for infective endocarditis (IE) have been proposed by the Duke University Endocarditis Service (Durham, NC) to update the widely used Beth Israel (Boston) criteria. We compared the Duke criteria with the Beth Israel criteria in a series of 115 consecutive patients with suspected IE who were hospitalized in a referral center. The diagnosis of IE was histologically and/or bacteriologically confirmed for 27 operated patients. If surgery had not been performed on these 27 patients, 22 vs. 12 would have been classified as having ¿clinically definite¿ and ¿probable¿ IE by the Duke vs. the Beth Israel criteria, respectively, whereas 0 vs. 5 would have been ¿rejected¿ by the Duke vs. the Beth Israel criteria, respectively. The improvement in sensitivity of the criteria from 44% (Beth Israel) to 82% (Duke) was statistically significant (P < .01). We confirm that the Duke criteria improve the sensitivity of diagnosis of IE. The specificity of these criteria should be further evaluated.

Use of cryomicrotomy to study gastric diffusion of amoxicillin in guinea pigs

Cryomicrotomy has been used as a new technique for removing gastric mucosae from adult guinea pigs for the study of amoxicillin secretion across gastric mucosae. This method allowed a very regular thickness of the removed surface layer of mucosa to be obtained with good reproducibility. Gastric superficial mucosa concentrations and gastric juice concentrations of amoxicillin were determined 1, 2, and 4 h after intramuscular administration (50 mg/kg) in 21 guinea pigs by a microbiological method. No antibiotic was detected in gastric samples at 4 h, except for a low-level mucosal concentration in one animal, thus indicating the short time that amoxicillin is present in gastric samples.

[Lumbar intervertebral disk. Intervertebral disk-vertebral body pathways and discal vascularization]

We studied the disco-vertebral interface and the blood supply of the intervertebral disks L3-L4, L4-L5, and L5-S1 of 5 human adult columns. Moreover, in order to investigate the discal vasculature, infusion of Japanese ink was used in 2 other adult columns, as well as immuno-histological methods in the L5-S1 disk of 4 adults and 2 infants. Our study confirms the paucity of discal vasculature in adults, by contrast with that of infants, but shows numerous defects in the subchondral vertebral plate, which are filled by vascularised medullary soft tissue and are in contact with the cartilaginous discal end plate. By these contacts, nutrients could reach the intervertebral disk, as suggested by other works, and as is the case in other cartilaginous structures of the body.

[Tubulo-papillary tumors of the kidney. Clinical, histologic and cytogenetic aspects. 15 new cases]

Between 1987 and 1992, we operated on 15 patients with tubulopapillary tumours (TPT) of the kidney, corresponding to 10% of all renal cancers operated during this 5-year period, which brings the total number of published cases to 418. TPT differ from non-tubulopapillary tumours in several ways. The medical imaging findings may differ when the tumour is not necrotic (20 to 30% of cases). The histology differs not only in terms of the tumour architecture, but also by the frequent association (9/15 cases) with other ipsilateral or contralateral renal anomalies: 2 bilateral tumours, 3 tumours associated with multiple cysts and 4 multifocal tumours. These characteristics, combined with the finding of 12 familial cases suggest a genetic origin for TPT, especially as the genetic abnormalities detected (tri-or tetrasomy 17) differ from the anomalies usually detected in non-tubulopapillary tumours (anomalies of 3p and 5q). This study is the first to report familial cases of TPT. The prognosis of these tumours, generally better than that of non-tubulopapillary tumours, suggests the possibility of conservative surgery when the diagnosis can be established preoperative or at operation.

Experimental articular toxicity of aluminum compounds in vivo

OBJECTIVE

To investigate the articular toxicity of 2 aluminum derivatives, one insoluble (hydroxide) and/or the other soluble (lactate), after a single administration in rabbits and rats.

METHODS

First, aluminum levels in plasma, urine, synovial tissue, liver and kidney were measured in saline treated rabbits and 1 to 2 days after an articular injection of 75 mg of aluminum compounds into their right knee. The methodology used was argon plasma emission spectrometry. Thereafter, the joint toxicity of aluminum lactate at the same dose regimen was evaluated for 2 days by a qualitative histological examination of synovial tissue and articular surfaces and a colorimetric assay (1,9-DMB) of patellar articular cartilage proteoglycan content. Secondly, the single injection of 50 mg of aluminum derivatives as an inducer of inflammation was studied in the rat subcutaneous air pouch, a model for a synovial-like space. Leukocytes and eicosanoids levels were measured in pouch washout fluids from 1 to 72 h after injection.

RESULTS

After injection into rabbit knee, aluminum lactate largely distributed within the body while hydroxide remained locally. However, aluminum lactate resulted in perivascular edema, sparse infiltration of inflammatory cells in the synovium and a hemorrhagic effusion. Proliferation of the synovial cell layer coexisted with an apparent loss of proteoglycan in superficial zones of tibial and femoral cartilages when patellar proteoglycan content remained unchanged. Aluminum hydroxide did not affect joint structures. In the air pouch experiment, aluminum lactate increased prostaglandin E2 (PGE2) levels from 3 to 10 h after its injection and less intensively leukotriene B4 (LTB4) levels after 6 h, in the absence of leukocytes migration into the cavity. In contrast, aluminum hydroxide increased leukocytes count in pouch-washout fluid from 3 to 24 h after its injection when PGE2 and LTB4 levels were little modified.

CONCLUSION

Although some differences attributable to dissimilarities in the experimental model used, aluminum compounds, even in a soluble form, may damage joint structures either directly or through stimulating the secretion of eicosanoids by synovial-like cells.

Enthesitis of the ligamentum teres during ankylosing spondylitis: histopathological report

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Subcellular localization of cytochrome P450, and activities of several enzymes responsible for drug metabolism in the human brain

We studied the subcellular distribution of cytochrome P450 and related monooxygenase activities in six regions of human brains removed at autopsy. The content of total cytochrome P450 was found to be at least nine times higher in the mitochondrial fraction than in the microsomes in all the regions studied. However, cytochrome P450-dependent enzymatic activities which are representative of different isoforms metabolizing exogenous molecules exhibited a microsomal prevalence, a situation previously observed in rat brain. The other drug-metabolizing enzymes catalysing functionalization and conjugation reactions, presented the following characteristics in human brain: (i) a low activity of NADPH-cytochrome P450 reductase, which also catalyses the reduction of some xenobiotics; (ii) a high specific activity of the membrane-bound epoxide hydrolase; (iii) among the enzymes catalysing conjugation reactions, 1-naphthol-UDP-glucuronosyltransferase activity was barely or not detectable, whereas the mean glutathione-S-transferase activity was 15 times higher than the activity measured in rat brain. The presence of several drug-metabolizing enzyme activities in human brain microvessels, and particularly the high activity of epoxide hydrolase, suggests a participation of these enzymes in the metabolic blood-brain barrier.

Osteogenic anaplastic carcinoma of the thyroid

An unusual osteogenic anaplastic carcinoma of the thyroid developed in a 68-year-old man and showed follicular and osteosarcomatous components. Seven months after surgery and 70 mCi 131I treatment, a local tumor recurrence was found and showed an intense uptake of 99mTc-MDP on the bone scan. After a second operation, pathologic and immunostaining analysis revealed no more thyroid carcinoma but only osteosarcomatous cells. Chemotherapy was ineffective and the patient died with diffuse pulmonary metastases 26 months after the diagnosis. The importance of osteogenic sarcomatous differentiation is proven by the bone scan. Osteosarcoma of the thyroid is a rare but well known tumor. Usually these tumors do not contain any cells originating from the thyroid epithelium and only comprise sarcomatous components. Ten cases of undifferentiated carcinoma of thyroid origin with osteogenic component have been reported. These tumors have been recently included in undifferentiated carcinomas in the second edition of the WHO classification. The evolution and pathologic findings favor the hypothesis of a transdifferentiation of the thyroid cell into osteogenic cells.

Flow cytometric analysis of the cell cycle in chronic gastritis

Flow cytometric cell cycle analysis was recorded in gastric biopsy specimens from patients with normal gastric mucosa (GM), superficial gastritis (SG) and chronic atrophic gastritis (CAG). Cell-cycle analysis showed significantly higher percentages of cells in S- and S+G2/M-phase in CAG than in SG and normal GM (P < 0.0001). Moreover, CAG with severe or moderate atrophy showed significantly higher percentages of cells in S-phase (P < 0.05) and S+G2/M-phase (P < 0.02) than CAG with mild atrophy in antrum. In fundus, even if this increase was observed, it did not reach statistical significance. Consideration of concomitant pathologic findings such as oesophagite, gastric or duodenal ulcer, duodenite or benign polyp allowed a better differentiation of CAG both in antrum and in fundus. Significantly higher S-phase was observed in CAG with severe or moderate atrophy than in CAG with mild atrophy (P < 0.05). No statistically significant results were observed in patients with normal gastric mucosa or chronic gastritis and a concomitant pathologic finding.

Statistical analysis of histomorphological findings in medullary thyroid carcinoma: distinction between the different familial forms of the disease. G.E.T.C. Groupe d'Etude des Tumeurs a Calcitonine

A multifactorial analysis of morphological findings was performed on 153 cases of medullary thyroid carcinoma (MTC). The aim of the study was to utilize histological criteria to discriminate between MTC associated with multiple endocrine neoplasia type 2A (MEN 2A) and that associated with the inherited MTC only syndrome. The presence of fusiform cells associated with several other markers seemed to be more predictive of MEN 2A. A comparison of inherited MTC only and sporadic MTC only showed fusiform cells to be significantly less common in inherited MTC only. These results suggest that the inherited MTC only syndrome is a distinct clinical and morphological entity. Further investigations are needed to confirm the findings and understand its implications.

Auto-immune spondylodiscitis associated with collagen induced arthritis in rats: high field MRI findings

The spinal involvement of the tail was studied in Wistar Furth rats immunized with bovine native type II collagen. Focal caudal autoimmune spondylodiscitis occurred 5 weeks after sensitization, as assessed histopathologically. High field Magnetic Resonance Imaging (MRI) was useful in depicting these caudal abnormalities that were related to juxta-diskal enthesitis. The occurrence of such inflammatory enthesopathies could serve as an experimental approach for physiopathological and therapeutical studies of spondylarthropathies.

Influence of muramyl dipeptide on established experimental arthritis in rats

The effects of MDP, a potent inducer of cytokines, were studied in four batches of Wistar Furth rats with established experimental arthritis. Arthritic rats were given a daily sc injection of 10, 100, 200 or 400 micrograms MDP respectively. Muramyl dipeptide increased the severity of clinical events in a dose-dependent manner, with the exception of the 10 micrograms dose which was ineffective. The levels of anti-collagen antibodies were not however significantly enhanced by MDP. Radiological lesions and histological changes were maximal at high dosage regimens. Paradoxically, the acute phase reactive alpha 1 glycoprotein was little affected by MDP treatment.

[Phosphorus NMR spectroscopy. Its value in the diagnosis of metabolic myopathies. A case of Mac Ardle's disease]

Phosphorus nuclear magnetic resonance spectroscopy is a non-invasive method used to study muscle bioenergetics in vivo. A new case of Mc Ardle's disease (myophosphorylase deficiency) is reported here. In a context of metabolic myopathy this method can provide a diagnosis of glycogenosis. The spectra obtained at exercise and during recovery determine the degree of enzyme deficiency with satisfactory precision.

[Histoenzymologic study of the anterior part of the medial rectus muscle]

The anterior region of 16 medial rectus muscles has been studied using myosine. ATPase at pH 4.63. The authors find one third dark fibres type I like, ATPase positive and two thirds fibres type II like ATPase negative. Types II A, II B and II C are difficult to individualize.

[Malignant quadrivalvular dysplasia of Marfan syndrome in a neonate]

The authors report the case of a neonate who died early of refractory heart failure and presented with all the characteristics of Marfan's syndrome in its early form with articular retractions. There was clinical evidence of mitral, tricuspid and major aortic regurgitation. Two-dimensional and doppler echocardiography confirmed the prolapse of highly dystrophic valves and the quadrivalvar regurgitation. Typical lesions of the connective-elastic tissue were found at autopsy. The occurrence of malignant Marfan's syndrome in neonates seems to be exceptional; the syndrome may take the rare "en contractures" form. Death is not always ascribable to the cardiac pathology, this pathology being often less generalized than in our case which seems to be the first one where such diffuse and massive valval lesions have been observed. This particular form was comparable to the "congenital polyvalvular disease" described by Bahrati and Lev, except that the skeletal and visceral abnormalities of Marfan's syndrome are absent in that disease.

Cyst formation in gastric heterotopic pancreas: report of two cases

Cyst formation is an uncommon pathologic finding in heterotopic pancreas. It is sometimes reported in a duodenal location but very rarely in a gastric location and leads to very large lesions of unusual endoscopic and radiographic appearance. Two cases of gastric heterotopic pancreas are described in which cystic zones in the gastric wall were found at preoperative ultrasound or computed tomography.

Intra and juxtavagal paraganglia: a topographical, histochemical, and ultrastructural study in the human

The topographical, ultrastructural, and histochemical features of 23 human vagal paraganglia were analyzed. Nineteen of the 23 paraganglia were found in previously unreported sites; 18 of the 19 were in the cervical part of the nerve, between the carotid bifurcation and the superior thoraco-cervical inlet, and one paraganglion was located in the retrothyroidal part of the left inferior laryngeal nerve. The results of ultrastructural studies (2 cases), the histochemical and formaldehyde-induced-fluorescence studies (3 cases), and specific acetylcholinesterase activity (one case) demonstrate that these structures fulfill many of the modern criteria for paraganglionic tissue. In addition to paraganglia, single, isolated neurons or true micro-ganglia were always found along the trunk and branches of the vagus nerve when multiple sections were examined.

Microvascularization of the intracranial dura mater

The authors have studied the microvascularization of the intracranial dura mater by microradiographic and histologic examination of 73 injected anatomic specimens. There exists a very abundant superficial arterial plexus which also serves to supply the inner table of the cranial vault. This plexus is continuous, even at the walls of the venous sinuses and the dural septa. The arteries are for the most part tortuous. The veins may be satellites of the arteries or, on the contrary, from a plexiform network passing through crevices in the interior of the dural layer. The walls of these veins consist only of an endothelium to be seen within the fibrous layer of the dura. Often, the arteries compress the venous lumen; this dangerous situation probably explains the frequent occurrence of arteriovenous fistulae of the dura mater, known by the name of dural fistulae.

[Intestinal ganglioneuromatosis: histochemical, histoenzymological and ultrastructural study of a case]

Report of a child with disseminated ganglioneuromatosis of the gut. The complexity of the intestinal nervous system malformation is proved by histochemical, histoenzymological and ultrastructural studies. The malformation is characterized by: hyperplasia and hypertrophy of enteric plexus and nerves bundles in the meso, high acetylcholinesterase activity, aplasia of the sympathetic innervation with the exception of perivascular plexus, qualitative and likely quantitative integrity of the endocrine digestive system. These data are compared with similar observations in the literature.