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Y Grignon

Publications and source records attributed to Y Grignon.

34 records · Page 2Linked to original sources

Compensatory renal growth post fetal nephrectomy in the rabbit.

Compensatory renal growth post-nephrectomy is well documented both clinically and experimentally. However, little is known about the capacity for compensatory growth in utero. We performed unilateral nephrectomy in fetal rabbits and studied the growth of the contralateral kidney. Thirty fetal rabbits underwent in utero uninephrectomies at day 25 of gestation. On gestational day 28, all the fetuses were delivered by cesarean section and the ratios kidney weight/body weight of the operated fetuses were compared to those of control littermates. The kidneys were then analysed by histology. A significant increase in renal weight was observed. The histological study of the remaining kidneys indicated a statistically significant increase of the glomerular area which confirmed the renal hypertrophy. This experiment demonstrates the capacity for the rabbit to develop in utero compensatory renal growth.

Animals↗

[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?

Fetal Diseases↗

[MNGIE syndrome in 2 siblings].

Two siblings (one man, one woman), presenting with diarrhea, severe weight loss peripheral neuropathy, ophthalmoparesis, asymptomatic leukoencephalopathy were diagnosed as a new cases of Mitochondrial Neuro Gastro Intestinal Encephalomyopathy syndrome (MNGIE). Hirano (1994) defined four criteria for the diagnostic: peripheral neuropathy, ophthalmoparesis, gastro intestinal dysmotility, muscle biopsy with histologic features of mitochondrial myopathy (ragged-red fibers, muscle fibers with increased succinate deshydrogenase stain or ultra structurally abnormal mitochondria). In a review of the literature, we found 31 cases with MNGIE. With our two cases, we study this group of 33 patients. First symptoms begin about 13.5 years with a median of 10 years and extremes for 1 to 32 years. The first signs are gastro intestinal symptoms (recurrent nausea, vomiting or diarrhea with intestinal dysmotility) in 22 cases, an ophthalmoparesia in 4 cases, intestinal and ocular signs in 1 case, gait ataxia or peripheral neuropathy in 3 cases, hearing loss in 1 case, gait ataxia or peripheral neuropathy in 3 cases, hearing loss in 1 case. During the evolution, besides the cardinal signs, the following features have been observed with a variable frequency: hearing loss, short stature, facial palsy, dysphonia, dysarthria, sweating, orthostatic hypotension, bladder dysfunction, hepatomegalia, The laboratory features are: abnormal Nerve Condition Studies/EMG compatible with a sensory motor neuropathy, lactic acidosis, mitochondrial respiratory chain defect (essentially complex IV deficiency, complex I deficiency or multiple complex defect), MRI leukodystrophy, elevated CSF protein, heart block, ragged-red fibers or increased SDH stain. The prognosis is poor, due to a severe weight loss bordering on cachexia 13 patients died with a mean age of 28.5 years (median 24 years, extreme 3 years to 51 years). The prognosis seems to be worsened by a young age of onset. The 33 patients belong to 19 families with 7 cases of consanguinity. 25 patients had a brother, a sister or a cousin affected. The study of these families is compatible with an autosomic recessive transmission, suggesting a pathology of the nuclear genomi, probably impliying the control of the mitochondrial DNA replication. In fact, in 13 cases, a study of the mt DNA was realized: multiple deletions were founded in 6 cases, multiples mutations in one case, unique mutation in 1 case. In 5 cases ther was no evidence of abnormality. These precise etiology and pathophysiologic significance of the mt DNA deletions, and the heterogeneity of the modifications of the mt DNA remain unknown. However, the possibility of various phenotypes for a same genotype or inversely is known in mitochondriopathies.

Adult↗

Hepatitis C after renal transplantation: histopathological correlations.

This study evaluates the correlations between liver histology, cytolysis, cryoglobulinaemia, co-infection with hepatitis B virus, and immunosuppressive treatment in renal transplant patients with HCV infection. Forty-five of 378 kidney recipients (January 1973-September 1993) had anti-HCV antibodies (prevalence = 11.9%) detected by second generation ELISA (Abbott Pasteur). Viral RNA was detected in those patients by RT-PCR in serum and liver. HCV-positive patients underwent liver biopsy to assess their liver tissue lesions according to Knodell's score. Patients were also screened for Hbs, Hbc and Hbe antigens (ELISA, Abbott) and cryoglobulins (immunobinding, SEBIA). Of the 45 HCV+ patients, 38 (84.4%) had persistent viral replication in the serum and 29 of the 30 patients having undergone liver biopsy had PCR-positive liver tissue. The liver biopsies revealed no active hepatitis lesion in 14 patients (46.6%, Group CAH-), 16 (53.3%) had chronic active hepatitis (Group CAH+) and 3 (10%) had signs of cirrhosis. Comparing groups CH+ and CH- showed that viral replication was detected in all 16 patients with chronic active hepatitis, versus 10/14 patients in the CAH- group (P < 0.05). Patients were more frequently treated with azathioprine in the CH+ group (12/16 vs 8/14; P < 0.05). The duration of renal transplantation was significantly longer in patients with a Knodell score > 5 (58 +/- 56 months vs 35 +/- 29 months, P < 0.001). Incidence of co-infection with HBV was similar in both groups. The mean values of alanine aminotransferase correlated with the Knodell score (r = 0.4, P = 0.03). Mixed cryoglobulinaemia was more common in the replicant forms of HVC infection (12/38 vs 1/7, P < 0.0001). This study shows that liver histological lesions are correlated with HCV viral replication, are more frequent in patients treated with azathioprine and are more severe as the duration of transplant is longer.

Alanine Transaminase↗

[Nephronogenic nephroma: a benign kidney tumor in adults. Two case reports].

The authors report 2 cases of a benign and uncommon type of renal tumour in adult, the nephronogenic nephroma. The pathology is discussed and compared to other groups of solid renal tumour. The confusion with malign tumour is usual. According to radiological investigations and pathological analysis, aspects of surgical treatment are presented and discussed.

Aged↗

[Spontaneously involuting metastatic seminoma of the testis ("burned-out seminoma"). Report of a case presenting with supraclavicular adenopathy].

Metastatic testicular germ cell tumours with complete involution of the primary site, or "burned-out tumour", constitute a classical but rare entity, whether the initial cell type is seminomatous or non-seminomatous. The authors report one case of this type of tumour. The diagnosis is primarily based on ultrasonography, indicating the need for orchidectomy in the presence of an anomaly, followed by histology, revealing a fibrous scar with no tumour cells. Aetiopathogenic hypotheses are divided between ischaemic and immunological theories. Scrotal ultrasonography and tumour marker assays should be performed systematically in the presence of retroperitoneal adenopathy with normal testicular clinical examination.

Adult↗

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.

Adolescent↗

[Is the topography of Alzheimer's disease lesions a clue to their pathogenesis?].

Neurofibrillary changes, labelled by antitau antibodies and deposits, labelled by anti-A beta antibodies, were counted in 6 cortical areas in 29 prospectively studied cases (Charles Foix Longitudinal Study). The intellectual status had been assessed by the Blessed test score; 10% of the cases were found to be normal (score > 27), 10 other percents were deeply demented (score < 2) and the other cases were regularly distributed over the intermediate values. Tau positive neurofibrillary changes were present in the hippocampus and in the parahippocampal gyrus even in intellectually normal cases. They were found in a primary sensory cortex (the visual cortex) only in the most severely affected cases. Associative cortices were spared in the normal cases and in the least demented patients. They were involved only at a critical value of the Blessed Test Score. A beta deposits involved more areas than the neurofibrillary pathology and their distribution was less systematically organized. Their density was poorly correlated with the intellectual status. Neuritic plaques, made of an amyloid core and of a crown of tau positive neurites, were present only in those areas that also contained neurofibrillary tangles. Our findings support the contention that neurofibrillary pathology, involving a set of short range, "feed-backward", cortico-cortical connections, is a close correlate of dementia. The role of A beta deposits remains unclear. Although poorly connected with dementia, they could be the remote initiator of the pathological cascade that leads to the neurofibrillary pathology, immediate cause of the cortical dysfunction.

Aged↗

[Contribution of bronchoalveolar lavage and transbronchial biopsy to diagnosis and prognosis of drug-induced pneumopathies].

This survey reports on 10 case-studies of drug-induced pneumonitis. The drugs under consideration are amiodarone, methotrexate, chlorambucil, sulindac, nilutamide-leuproreline, cyclothiazide, with the possible addition of bleomycin. In each case, one or more bronchoalveolar lavage were carried out and in most cases it was also possible to perform a transbronchoscopic lung biopsy. The results of these tests are analysed in order to ascertain their contribution to diagnosis and prognosis. Regarding diagnosis, bronchoalveolar lavage does not evidence a typical cellular configuration characterizing drug-induced alveolitis. Moreover, transbronchoscopic lung biopsy plays no part in diagnosing this pathology. Both these tests, however, help to eliminate other hypotheses. Regarding prognosis, transbronchoscopic lung biopsy provides no information, unlike bronchoalveolar lavage in which a high rate of neutrophils in the lavage fluid is sometimes associated with the development of pulmonary fibrosis.

Acute Disease↗

[Mesangial IgA deposits nephropathy].

Idiopathic IgA nephropathy of Berger's disease is characterized by prominent and diffuse IgA deposits in the mesangium. In many countries, it is the most common type of primary chronic glomerulonephritis. Typically, it is revealed by recurrent episodes of gross hematuria in association with ENT infection, but it can progress insidiously with microscopic hematuria and proteinuria. Serum IgA levels are increased in about 50% of cases. IgA nephropathy is not a minor condition: 20% of patients develop end-stage chronic renal failure 10 years after diagnosis and 50% after 20 years. IgA nephropathy can recur in a transplanted kidney suggesting that this disease is a systemic disorder although it has a remarkable tropism for the kidney. Even though many points remain to be elucidated, its pathogenesis appears to be linked to a genetic factor responsible for a lymphocyte dysfunction and an acquired environmental factor such as penetration of an antigen via the mucosa which may give rise to an excessive and inappropriate IgA immune response with the deposition of IgA in the mesangium and the development of progressive renal alterations. No treatment has been shown to be effective but tonsillectomy advised in case of a recurrent tonsillar focal infection is most often accompanied by a decrease in the incidence of gross hematuria. Corticosteroid therapy can be of benefit in cases involving a nephrotic syndrome associated with minimal glomerular lesions. In all cases, control of possible hypertension is of value in slowing the progression of this disease.

Adolescent↗

[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.

Adenocarcinoma, Papillary↗

Modeling the relation between neurofibrillary tangles and intellectual status.

The relationship between the neurofibrillary tangles and the intellectual deficit observed in senile dementia of the Alzheimer type was studied in 27 patients over the age of 75. The presence and density of tau positive tangles were assessed in six areas including limbic, paralimbic, and isocortical cortices. In the isocortical areas, the presence [1] or absence [0] of neurofibrillary tangles was better correlated with the Blessed test score than the density of the neurofibrillary tangles profiles. Multivariate analysis showed that the number of areas containing at least one neurofibrillary tangle was the best explanatory variable of the intellectual status. The cortical areas were ranked according to the prevalence of their involvement. The presence of tangles in an area of a given rank took place only if the areas of lower ranks were also involved. It is proposed that the presence of tangles in a given area is a more significant information than the value of their density. These data may lead to new diagnostic procedures.

Aged↗