Measurement of the Cosmic Ray Helium Energy Spectrum from 70 GeV to 80 TeV with the DAMPE Space Mission

The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the Dark Matter Particle Explorer (DAMPE) is reported in this work. A hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of 4.3σ. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out.

Breastfeeding and early childhood caries. Review of the literature, recommendations, and prevention

CONTEXT

Early childhood caries is a chronic disease that affects a child's general state of health. The question of a link between primary tooth caries and breastfeeding has been addressed for many years, with contradictory results. The concomitant decay of primary teeth, effective establishment, or not, of oral hygiene, and alimentary diversification away from breastfeeding are all confounding factors in this topic. The aim of our study was to analyze the links between breastfeeding and the appearance of caries, as described in the scientific literature and in the recommendations of specialist societies.

METHODS

A review of publications written in English and French was carried out, searching for the terms early childhood caries, decay and breastfeeding, focusing on literature reviews and meta-analyses dating from the past 10 years. The PubMed database of the US National Library of Medicine National Institutes of Health (NBCI) was used. Furthermore, a review of specialist dental and pediatric societies was conducted.

RESULTS

Breastfeeding until the age of 1 year is not associated with an increased risk of dental caries, and may even provide protection compared with feeding with formula milk. By contrast, infants who are breastfed beyond the age of 12 months demonstrate an increased risk of caries. However, the results derive from heterogeneous studies that do not always take into account contradictory factors such as eating habits of the mother or infant (feeding during the night, number of meals per day, eating sweet foods etc.), dental hygiene, or the sociocultural context. Moreover, the most recent recommendations of pediatric and dental societies advise breastfeeding until the age of 2 years, suggesting that this be accompanied by toothbrushing and better nutrition by reducing the frequency and consumption of sugary foods, aimed at helping parents choose prolonged breastfeeding.

CONCLUSION

Extended breastfeeding is a protective factor for childhood caries under 1 year of age. Beyond 1 year, it is difficult to conclude between protection and aggravation of caries because of the multiplicity of confounding factors such as dietary patterns, which vary depending on countries and families, and problems of oral hygiene. In practical terms, when breastfeeding continues beyond 1 year, consultation with a dentist is necessary for examination and preventive advice regarding dietary practices (especially sugar intake), oral hygiene, or supplementary fluoride.

Measurement of the cosmic ray proton spectrum from 40 GeV to 100 TeV with the DAMPE satellite

The precise measurement of the spectrum of protons, the most abundant component of the cosmic radiation, is necessary to understand the source and acceleration of cosmic rays in the Milky Way. This work reports the measurement of the cosmic ray proton fluxes with kinetic energies from 40 GeV to 100 TeV, with 2 ¹/₂ years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time that an experiment directly measures the cosmic ray protons up to ~100 TeV with high statistics. The measured spectrum confirms the spectral hardening at ~300 GeV found by previous experiments and reveals a softening at ~13.6 TeV, with the spectral index changing from ~2.60 to ~2.85. Our result suggests the existence of a new spectral feature of cosmic rays at energies lower than the so-called knee and sheds new light on the origin of Galactic cosmic rays.

Dental caries and enamelin haplotype

In the literature, the enamelin gene ENAM has been repeatedly designated as a possible candidate for caries susceptibility. Here, we checked whether ENAM variants could increase caries susceptibility. To this aim, we sequenced coding exons and exon-intron boundaries of ENAM in 250 children with a severe caries phenotype and in 149 caries-free patients from 9 French hospital groups. In total, 23 single-nucleotide polymorphisms (SNPs) were found, but none appeared to be responsible for a direct change of ENAM function. Six SNPs had a high minor allele frequency (MAF) and 6 others were identified for the first time. Statistical and evolutionary analyses showed that none of these SNPs was associated with caries susceptibility or caries protection when studied separately and challenged with environmental factors. However, haplotype interaction analysis showed that the presence, in a same variant, of 2 exonic SNPs (rs7671281 and rs3796704; MAF 0.12 and 0.10, respectively), both changing an amino acid in the protein region encoded by exon 10 (p.I648T and p.R763Q, respectively), increased caries susceptibility 2.66-fold independent of the environmental risk factors. These findings support ENAM as a gene candidate for caries susceptibility in the studied population.

Common SNPs of AmelogeninX (AMELX) and dental caries susceptibility

Genetic approaches have shown that several genes could modify caries susceptibility; AmelogeninX (AMELX) has been repeatedly designated. Here, we hypothesized that AMELX mutations resulting in discrete changes of enamel microstructure may be found in children with a severe caries phenotype. In parallel, possible AMELX mutations that could explain resistance to caries may be found in caries-free patients. In this study, coding exons of AMELX and exon-intron boundaries were sequenced in 399 individuals with extensive caries (250) or caries-free (149) individuals from nine French hospital groups. No mutation responsible for a direct change of amelogenin function was identified. Seven single-nucleotide polymorphisms (SNPs) were found, 3 presenting a high allele frequency, and 1 being detected for the first time. Three SNPs were located in coding regions, 2 of them being non-synonymous. Both evolutionary and statistical analyses showed that none of these SNPs was associated with caries susceptibility, suggesting that AMELX is not a gene candidate in our studied population.

Clinical decision on pit and fissure sealing according to the occlusal morphology. A descriptive study

BACKGROUND

The objective of this descriptive study was to evaluate the clinical decision on sealing pits and fissures according to the occlusal morphology in patients with low individual caries risk (ICR).

MATERIALS AND METHODS

A total of 222 dentists, 86 affiliated to the French Society of Paediatric Odontology (SFOP) and 136 general practice dentists (GPs), answered the same questionnaire with illustrations of 4 occlusal surfaces of permanent molars: they indicated firstly if these were at risk and secondly the corresponding decision regarding sealing. This questionnaire assessed the decision on widening pits and fissures before sealing and the type of sealant material used. Multivariate logistic regression analyses were performed to identify the factors associated with the clinical decision to widen pits and fissures.

RESULTS

Sealing of at-risk teeth was indicated by 89% of dentists, whereas sealing of not at-risk occlusal surfaces was recommended by 46%. SFOP dentists were more prone to recommend pit and fissures sealants. The multivariate analyses demonstrated that only the type of material was associated with the clinical decision to widen pits and fissures. Forty eight percent of dentists choose the same material in all clinical situations.

CONCLUSION

The wide variations in sealant use and placement technique implies there is no apparent consensus among GP and SFOP dentists. Although the criteria are similar in numerous scientific societies, not all dentists are acting upon these recommendations.

Thrombotic microangiopathy in adult Still's disease

Adult Still's disease (ASD) is a rare systemic disorder characterized by fever, arthralgia, cutaneous rash, and lymphadenopathy, with high polymorphonuclear leucocytosis and low glycosylated ferritinaemia. Kidney involvement has been reported rarely. We present a patient with ASD who developed haemolytic uraemic syndrome (HUS). The 42-year-old patient was admitted for unexplained fever related to ASD according to Yamaguchi's classification criteria. As Still's disease was resistant to prednisone, high-dose intravenous immunoglobulins (IV Ig) were administered. During the follow-up the patient developed acute renal failure and non-immune haemolytic anaemia with high levels of antiphospholipid antibodies (IgG anticardiolipin antibodies and anti-beta2 glycoprotein 1 antibodies). Renal biopsy disclosed thrombotic microangiopathy (TMA) with arteriolar and glomerular involvement. Treatment with steroids and intravenous IV Ig was reinitiated but renal function worsened towards end-stage renal failure. In this case, we suggest that antiphospholipid antibodies could have promoted arteriolar and glomerular TMA. HUS may be the cause of acute renal failure in Still's disease.

A simple clinico-histopathological composite scoring system is highly predictive of graft outcomes in marginal donors

The predictive value of pre-implantation biopsies versus clinical scores has not been studied extensively in marginal donors. Pre-implantation biopsies were performed in 313 kidneys from donors that were > or = 50 years of age (training set, n = 191; validation set, n = 122). The value of the donor clinical parameters and histological results in predicting 1-year estimated glomerular filtration rate (eGFR) <25 mL/min/1.73 m(2) was retrospectively evaluated. In multivariate analysis, the only clinical parameters associated with low eGFR were donor hypertension and a serum creatinine level > or =150 micromol/L before organ recovery. Clinical scores (Nyberg and Pessione) were not significantly associated with graft function. Regarding histological parameters, univariate analysis showed that glomerulosclerosis (GS) (p = 0.02), arteriolar hyalinosis (p = 0.03) and the Pirani (p = 0.02) and chronic allograft damage index (CADI) (p = 0.04) histological scores were associated with low eGFR. The highest performance in predicting low eGFR was achieved using a composite score that included donor serum creatinine (> or =150 micromol/L or <150 micromol/L), donor hypertension and GS (> or =10% or <10%). The validation set confirmed the critical importance of taking into account biopsy and clinical parameters during marginal donor evaluation. In conclusion, clinical scores are weak predictors of graft outcomes with marginal donors. Instead, a simple and convenient composite score strongly predicts graft function and survival and may facilitate optimal allocation of marginal donors.

[Nephrotic syndrom with focal and segmental glomerulosclerosis in Dakar: epidemiological and clinicopathological characteristics (about 134 cases)]

Focal and segmental glomerulosclerosis (FSGS) is common and non-specific patterns of glomerular injury encountered in human renal biopsies. Cortico-resistant nephrotic syndrome is the main manifestation. We report epidemiological, clinical and pathological aspects of FSGS in Dakar. We report the results of a retrospective study about focal segmental glomerulosclerosis (FSGS) identified from 258 kidney biopsies performed in the medical clinic 1 of A. Le Dantec hospital from January 1993 to December 2003. FSG is found in 134 cases (52%), membranous glomerulonephritis in 32 cases (12,4%), minimal change disease in 20 cases (7.7%). Ninety eigths files were exploitable. FSGS has male gender predominance with a sex ratio of 3. Median age of patients is 28 years (15 and 79 years). Symptomatology is dominated by oedema in 86 cases (87,7%), hypertension in 12 cases (12.2%), hematuria in 5 cases (5.1%), nephrotic proteinuria in 65 cases (66,3%) and no nephrotic proteinuria in 33 cases (33.6%), renal failure in 25 cases (25%)and leucocyturia in 18 cases (18%). FSGS involving more than 50% of glomeruli is encountered in 41 cases (42%), severe interstitial fibrosis is associated in 26 cases. Different pathological aspects are: classical FSGS in 88 cases (88.7%), FSGS " collapsing" in 7 cases (7.1%), FSG "tip-lesion" in one case, FSGS associated to membranous glomerulosclerosis in 2 cases and to diabetic glomerulosclerosis in one case. FSGS is primitive in 88 cases (89,8%) and secondary in 10 cases (10.2%). FSGS is the most common primitive glomerulopathy in Dakar. Nephrotic syndrome is the main manifestation of this disease. Collapsing FSGS is not correlated with the HIV Infection.

Enquête épidémiologique sur la santé buccodentaire d'enfants âgés de 4 ans scolarisés en école maternelle

The departmental service of maternal and infantile protection (PMI) of Moselle (Lorraine region), together with the Paediatric Dentistry Department from Nancy University, organized a study of the dental health of 4-year-old children.

AIMS OF THE STUDY

To assess the children dental health; to evaluate parental knowledge of dental health; to identify the factors associated with caries amongst children.

MATERIAL AND METHODS

The study was a cross sectional observation. A random sample of 4-year-old children was selected among 11 586 children in nursery schools. The study was based on a clinical examination performed by a dentist and a structured questionnaire completed by parents.

RESULTS

The overall proportion of children affected by caries was 37.5%. The mean dmft score was 1.51 (sd = 2.82) and 11.6% of the children had caries which affected their upper incisors, a sign of early childhood caries. Only 6.2% had received dental treatment on at least 1 occasion. There was a clear disparity in dental health: 1 child out of 3 suffered from caries but 1 out of 2 children in priority education districts was affected, compared with only 1 out of 4 children coming from a rural area. The questionnaires completed by parents showed a lack of knowledge of dental health and inadequate use of current prevention facilities. The multivariate logistic regression analysis showed that the variables that were significantly associated with caries in 4 year-old children were the mother's education, the low social background, the level of consumption of drinks containing sugar by both children and parents, the consumption of fluoride, and the level of knowledge about fluoride.

CONCLUSION

Preventive measures must be developed in close relationship between pediatricians and dentists. Initial training of health care professionals has to be reinforced. Health care professionals in paediatrics are far more likely to meet mothers and young children than are dentists.

[A rare cause of pulmonary-renal syndrome with autoantibodies: primary antiphospholipid syndrome]

We present a case of primary antiphospholipid syndrome with acute renal failure and alveolar haemorrhage. He was successfully treated with cyclophosphamide, corticosteroids and plasma exchange. Patients with antiphospholipid syndrome may develop a broad spectrum of pulmonary disease. Pulmonary thromboembolism and pulmonary hypertension are the most common complications, but alveolar haemorrhage have also been reported. Other causes need to be excluded. Despite favourable outcome of many patients with association of plasma exchange, immunosuppressive drugs and anticoagulant therapy, definite conclusions about the best therapeutic regimen could not be draw.

Pulmonary-renal syndrome due to hemorrhagic fever with renal syndrome: an unusual manifestation of puumala virus infection in France

The authors report about a patient who presented with acute respiratory failure, bilateral alveolar infiltrates, without signs of fluid overload, and acute renal failure. Percutaneous renal biopsy revealed acute interstitial nephritis with medulla hemorrhages. Serologic tests for Puumala virus infection were positive. Hemorrhagic fever with renal syndrome should be considered when patients present with pulmonary-renal syndrome.

Low grade marginal zone B cell lymphoma of the breast associated with localised amyloidosis and corpora amylacea in a woman with long standing primary Sjögren's syndrome

Primary low grade marginal zone B cell lymphoma (MZL) of the breast and localised mammary amyloidosis are exceedingly rare entities. This report describes the case of a woman with long standing Sjögren's syndrome presenting with asymptomatic MZL of the breast showing plasmacytic differentiation, associated with local ductular amyloidosis. The lesion was discovered incidentally in breast tissue resected for microcalcifications. Immunohistochemistry revealed kappa light chain restriction, supporting the neoplastic nature of the infiltrate. A retrospective molecular study of the salivary gland biopsy showed a B cell clone. This is the first report of the association of human mammary ductular amyloidosis with cartwheel shaped material identical to corpora amylacea, usually seen in brain, lung, and prostate, but unknown in the human breast. The excellent outcome without treatment seen in this patient further emphasises the need to distinguish between MZL with plasmacytic differentiation and extramedullary plasmacytoma.

[Tracheobronchial amyloidosis: apropos of 2 cases]

INTRODUCTION

Tracheo-bronchial amyloidosis is an uncommon localized form of amyloidosis. We report two new cases.

EXEGESIS

Two patients had developed expiratory dyspnea for several months. CT-scan and flexible bronchoscopy confirmed tracheal narrowing and a diagnosis of tracheo-bronchial amyloidosis was made by tissue biopsies. The immunohistochemical type was AL in one case, undetermined in the other case. There was no argument for systemic involvement. The two patients benefited from bronchoscopic dilatation. This treatment improved clinical symptoms and pulmonary function tests with a follow up of 12 and 18 months respectively.

CONCLUSION

Tracheo-bronchial amyloidosis is a localised form of amyloidosis with various respiratory symptoms. Diagnosis is made by CT-scan and flexible bronchoscopy that allows biopsies. Immunohistochemical type is more often AL. Recurrence, respiratory insufficiency and tracheo-bronchial metaplasia are the most important complications. Treatment consists of bronchoscopic dilatation or excision, and bronchoscopic laser-YAG. Pulmonary function testing allows precise follow-up.

One-year routine renal transplant biopsies in children

In our institution, systematic renal graft biopsies are performed 1 year after transplantation before deciding to switch to alternate-day steroid therapy, which has been shown to be beneficial for statural growth. We analyzed the results of systematic graft biopsies in 145 children with a creatinine clearance > or =45 ml/min per 1.73 m2. Biopsies were classified according to Banff diagnostic categories. Normal parenchyma was observed in 19 cases (13%), non-specific lesions in 42 cases (29%), chronic allograft nephropathy grade 1-3 in 68 cases (49%), and acute rejection in 8 cases (5%). Clinicopathological correlations indicated that patients with chronic allograft nephropathy had received kidneys from older donors, with longer cold ischemia time and with a higher incidence of delayed graft function. There was a strong correlation between the donor age and the presence of vascular lesions. There was also a good correlation between the severity of histological lesions and the occurrence of acute rejection episodes during the 1st year after transplantation. Renal function remained stable for up to 10 years in patients with normal parenchyma or non-specific lesions, while serum creatinine levels increased after the 2nd year in patients with chronic allograft nephropathy.

Granulomatous renal disease in a patient with common variable immunodeficiency

Common variable immunodeficiency (CVID), the most common cause of primary hypogammaglobulinemia, is characterized by a decreased serum immunoglobulin level, recurrent infections, and the occurrence of various autoimmune diseases. Granulomatous disease has been reported previously in several patients with CVID, with granuloma occurring in the lymph nodes, spleen, liver, central nervous system, and bone marrow. We report the first published case of renal granulomatous disease in a CVID patient presenting with subacute renal failure. Renal function partially recovered after corticosteroid treatment and intravenous immunoglobulin infusions. The pathogenesis of granulomatous disease in CVID is unclear but may involve monocyte and T-cell abnormalities.

Association of GSTT1 non-null and NAT1 slow/rapid genotypes with von Hippel-Lindau tumour suppressor gene transversions in sporadic renal cell carcinoma

The von Hippel-Lindau (VHL) tumour suppressor gene is commonly mutated in renal cell carcinoma of clear cell type (CCRCC). We investigated the possible relationship between VHL mutations in sporadic CCRCC and polymorphism of genes encoding enzymes involved in carcinogen metabolism: two cytochrome P450 monooxygenases (CYP1A1 and CYP2D6), one NAD[P]H:quinone oxidoreductase (NQO1), three glutathione S-transferases (GSTM1, GSTT1 and GSTP1) and two arylamine N-acetyltransferases (NAT1 and NAT2). We analysed DNA from tumour and nontumoural kidney tissue from 195 CCRCC patients. Single VHL mutations were identified in 88 patients and double mutations were present in two patients. Nine of 18 transversions were GC to TA, four were AT to TA, four were GC to CG and one was AT to CG. Ten of 19 transitions were GC to AT and nine were AT to GC. We also identified 53 frameshifts and two GC to AT at CpG. An excess of transversions was observed in a subset of patients with active GSTT1 [GSTT1 (+) genotype] and probably defective NAT1 (NAT1 S/R variant genotype). All 18 transversions were in GSTT1 (+) patients, whereas only 76% of transitions (P = 0.05) and 81% of the other mutations (P = 0.06) occurred in this genotype. We found that 28% of the transversions were in the NAT1 S/R genotype versus 12% of the transitions (P = 0.40) and 4% of the other mutations (P = 0.01). This suggests that pharmacogenetic polymorphisms may be associated with the type of acquired VHL mutation, which may modulate CCRCC development.

[Fluoride and children]

Fluoride is considered as an essential carioprophylactic agent. However, its use raises problems related to the possible negative effects of excessive intake. Precautions are therefore necessary when prescribing fluoride to children. This includes: 1) evaluation of all sources of fluoride for each individual child and his/her family; 2) evaluation of the cariogenic risk for the child according to his/her environment; and 3) estimation of the family's ability to follow medical advice and prescriptions. The role of the practitioner is thus to adapt the fluoride prescription according to the age and particular cariogenic susceptibility of each child. Pediatricians, general practitioners and dentists need to be convinced of how important regular visits to the dentist are for all children, from an early age. Not only fluoride, but also nutrition and hygiene are essential factors in achieving good dental health in childhood.

Distribution of alphavbeta3, alphavbeta5 integrins and the integrin associated protein--IAP (CD47) in human glomerular diseases

The alphav integrins present on the membrane of numerous cells, mediate attachment to matrix proteins, cell proliferation, migration and survival. We studied the expression of alphav integrinis and CD47 (a beta3 chain integrin associated protein) in various forms of glomerulonephritis (GN) characterized by mesangial proliferation and/or increased mesangial matrix. In normal glomeruli, epithelial cells expressed alphavbeta3, alphavbeta5 and CD47; endothelial cells expressed alpha5beta1 and CD47; mesangial cells expressed alphavbeta5, CD47, and to a less extent alphavbeta3. In acute post infectious GN (APIGN), membrano-proliferative GN (MPGN) and diabetic nephropathy(DN), we observed that the beta3 chain, normally expressed by mesangial cells, was not detectable in the mesangium while its expression by epithelial cells was not modified. Parallel to the disappearance of alphavbeta3, the CD47 expression was decreased on the mesangial cells in MPGN, APIGN and DN. The expression of alphavbeta5 was clearly increased on podocytes and on proliferating mesangial cells in APIGN. By contrast, the mesangial expression of alphavbeta was normal or decreased in DN. The alpha5 chain of integrin, absent on normal mesangial cell, was expressed on proliferating mesangial cells in MPGN and APIGN. Thus, we observed modifications of alphavbeta3 and alphavbeta5 expression during human GN. The modulations of alphavbeta3 and alphavbeta5 expression differed according to the different glomerular cell types and were not parallel in glomerular cells: alphavbeta3 was decreased (and alphavbeta5 unchanged) on proliferating mesangial cells and alphavbeta5 was increased (and alphavbeta3 unchanged) in podocytes. This may reflect the existence of two distinct regulatory pathways.

[Prevention of renal carcinoma: the nutri-genetic approach]

The development of renal cell carcinoma (RCC) has been associated with both genetic and environmental factors, with somatic and germline mutations in the von Hippel-Lindau (VHL) tumor suppressor gene and with tobacco smoking, obesity, long term exposure to some nutrients, pollutants, and industrial solvents such as trichloroethylene. Intra and interfamilial variability of expression of germline mutations in the VHL gene and variable susceptibility to carcinogens in the sporadic forms strongly suggest the involvement of conditional modifier genes. In order to identify sub groups of individuals at increased risk because of susceptibility genotypes, we have collected a series of 460 patients who developed an RCC and 79 families with the von Hippel Lindau disease. To collect clinical and mutational data for correlation analysis we have developed a unique tool the Universal Mutation Database. Comparison of the spectrum of germline and somatic mutations in the VHL gene showed that: 1) in sporadic RCC mutations lead more often to truncated proteins (83%), while the remaining mutations (17%), include 3/4 of transversions and 1/4 of transitions. This high proportion of transversions supports the involvement of carcinogens the impact of which is conditioned by the genetic variability of xenobiotic metabolizing enzymes; 2) whereas in familial cases missense mutations are more common; this difference allowed us to define a prognostic factor for the occurrence of RCC in a VHL context. In order to look for genotypes conferring a higher risk we genotyped the RCC patients for 8 different genes (50 genotypes). A significant relationship was observed for several combinations of alleles including CYP1A1 ("variant"), NAT2 and NAT1 (slow) and GSTM1 (null allele). Associations between specific mutational profiles and at risk genotypes at different tumoral stages should allow us to: 1) define more precisely the nature of specific patterns of mutations in relation with the deficiency or overexpression of such or such enzymes in presence of particular carcinogens; 2) demonstrate that certain combinations of genotypes confer a particular risk to develop a specific type of tumor in VHL patients. Thus tracking of potentially carcinogenic substances, through their footprints and through identification of conditionally detrimental genotypes of genes participating in their detoxification should permit a better prevention through an appropriate nutrition adapted to each individual.

Mutations of the VHL gene in sporadic renal cell carcinoma: definition of a risk factor for VHL patients to develop an RCC

To investigate the nature of somatic von Hippel-Lindau (VHL) mutations, we analyzed 173 primary sporadic human renal cell carcinomas for mutations of the VHL tumor suppressor gene, using polymerase chain reaction (PCR) and single-strand conformational polymorphism analysis (SSCP) of DNA. We detected abnormal SSCP pattern in 73 samples. After sequencing, we identified microdeletions in 58% of cases, microinsertions in 17%, nonsense mutations in 8%, and missense mutations in 17%. Among these mutations, 50% correspond to new mutations. VHL mutations were found only in the nonpapillary renal cell carcinoma (RCC) subtype, as previously reported. To compare somatic and germline mutations, we used the VHL database, which includes 507 mutations. The study of mutational events revealed a significant difference between somatic and germline mutations with mutations leading to truncated proteins observed in 78% of somatic mutations vs only 37% in germline mutations (P < 0.001). We postulated that a specific pattern of VHL mutations is associated with sporadic RCC. This pattern corresponds to mutations leading mainly to truncated proteins with few specific missense mutations. We then analyzed the occurrence of RCC in VHL families, based on the nature of mutations. We observed RCC in at least one member of the VHL families in 77% of cases with mutations leading to truncated proteins versus 55% in cases with missense mutations (P < 0.05). Thus, mutations resulting in truncated proteins may lead to a higher risk of RCC in VHL patients.

[Fabry disease: clinical aspects and therapeutic perspectives]

Fabry's disease is one of the lysosomal disorders. It is due to a hereditary alpha-galactosidase A defect with X-linked recessive transmission. A majority of hemizygotes develop severe multisystemic involvement (classic form), dominated by relentless renal failure and progressive neurological and cardiac lesions. Nevertheless, some affected individuals retain sufficient enzyme activity and long remain asymptomatic (atypical form); their main manifestation is hypertrophic cardiomyopathy. Female carriers are usually asymptomatic; 15%, however, have severe involvement of one or more organs. Laboratory, histological and molecular diagnosis identifies 100% of hemizygotes and over 80% of heterozygotes. With recent developments in molecular genetics it is possible to produce the human recombinant enzyme alpha-GALA. Its effects in hemizygous patients remain to be evaluated. In addition, the results of a trial of gene therapy in a Fabry's disease gene knocked-out mouse appear promising. These new therapeutic approaches will probably soon provide substitutive treatment for Fabry's disease as well as for so-called "orphan" diseases.

Renal lesions in von Hippel-Lindau disease: immunohistochemical expression of nephron differentiation molecules, adhesion molecules and apoptosis proteins

AIMS

Renal lesions in von Hippel-Lindau disease comprise clear cell simple cysts, atypical cysts and carcinomas. Although histological and molecular studies suggest that cystic lesions may represent precursors of carcinomas, there is no detailed phenotypic evidence of their relationship.

METHODS AND RESULTS

To investigate such a possible relationship between cystic lesions and solid carcinomas, we studied the pathological and immunohistochemical features of 328 lesions of 33 kidneys originating from 23 patients with von Hippel-Lindau disease, using a panel of antibodies directed against cytoskeleton proteins, cell surface proteins, integrin subunits, adhesion molecules, lectins, and apoptosis and proliferation markers. Solid carcinomas (n = 175) were all of clear cell type and mostly nuclear grade 1. Cystic lesions (n = 138) consisted of cystic clear cell carcinomas (n = 15), atypical cysts (n = 20) and simple cysts (n = 103). Clear cells of the simple cysts, atypical cysts and solid carcinomas coexpressed cytokeratins (CK8, CK19) and vimentin, and expressed a similar pattern of tubular markers (CD24, tetraglonolobus), integrin subunits (alpha3, alpha5, alpha6, alphav, beta1) and cell adhesion molecules (ICAM 1, VCAM 1). In all lesions studied, proliferation rate (MIB1 index) was low, and apoptosis marker expression (fragmented DNA, p53, bcl-2) inconspicuous.

CONCLUSIONS

Phenotypic alterations found in solid renal cell carcinomas are already present in simple and atypical renal cysts of von Hippel-Lindau disease.

[Renal cell carcinoma in a 14-year-old girl with Von Hippel Lindau disease]

We report a new case of renal cancer in the context of Von Hippel Lindau (VHL) disease in a 14-year-old girl. To our knowledge, this is the youngest case reported in the literature. VHL disease is now well known and its prognosis is related to renal cancer, which occurs very early in the patient's life, requiring adequate surveillance of patients carrying the VHL gene to ensure early diagnosis of the cancer, screening of family members and treatment, preferably conservative when permitted by the size and number of tumours, in these patients who are predisposed to developing other renal tumours, in order to delay bilateral nephrectomy and the need for dialysis or even transplantation, to a maximum.

Retinoic acid for treatment of multicentric Castleman's disease

Multicentric Castleman's syndrome has an aggressive course with poor prognosis, and its treatment remains uncertain. We report a woman with multicentric Castleman's disease that was successfully treated with prednisone and retinoic acid.

Candidate genetic modifiers of individual susceptibility to renal cell carcinoma: a study of polymorphic human xenobiotic-metabolizing enzymes

The steady increase in sporadic renal cell carcinoma (RCC) observed in industrialized countries supports the notion that certain carcinogens present in the environment (tobacco smoke, drugs, pollutants, and dietary constituents) may affect the occurrence of RCC. Many of the enzymes dealing with such environmental factors are polymorphic and may, therefore, confer variable susceptibility to RCC. This case-control study was designed to test for an association between genetic polymorphism of enzymes involved in xenobiotic metabolism and the risk of sporadic RCC. Genomic DNA was obtained from 173 patients with RCC and 211 controls of Caucasian origin. We used PCR-RFLP to investigate polymorphism for the most common alleles at two cytochrome-P450 mono-oxygenases (CYP1A1 and CYP2D6), one NAD[P]H:quinone oxidoreductase (NQO1), three glutathione S-transferases (GSTM1, GSTT1, and GSTP1), and one N-acetyltransferase (NAT2) loci. The CYP1A1 (m) "variant" genotype, which contains at least one copy of the CYP1A1 variant alleles, was found to be associated with a 2.1-fold [95% confidence interval (CI), 1.1-3.9] increase in the risk of RCC. There was also a higher risk of RCC for subjects with the CYP1A1 (m) variant genotype combined with any of the following genotypes: GSTT1 (+) "active" [odds ratio (OR), 2.3; 95% CI, 1.2-4.5], GSTP1 (m) variant (OR, 2.4; 95% CI, 1.0-5.4), or NAT2 (-) "slow acetylator" (OR, 2.5; 95% CI, 1.1-5.5). A significant association was also found for the GSTM1 (-) "null" and GSTP1 (m) genotypes combined with either NAT2 (-) (OR, 2.6; 95% CI, 1.2-5.8) or CYP1A1 (m) (OR, 3.5; 95% CI, 1.1-11.2). The CYP2D6 (-) "poor metabolizer " and the NQO1 (-) "defective" genotypes were not clearly associated with a higher risk of RCC. Our data demonstrate for the first time a significant association between a group of pharmacogenetic polymorphisms and RCC risk. These positive findings suggest that interindividual variation in the metabolic pathways involved in the functionalization and detoxification of specific xenobiotics is an important susceptibility factor for RCC in Caucasians.

The intrarenal vascular lesions associated with primary antiphospholipid syndrome

Even 10 yr after the identification of the antiphospholipid syndrome (APS), renal involvement in the course of APS is still relatively unrecognized, and is probably underestimated. The association of anticardiolipin antibodies and/or lupus anticoagulant with the development of a vaso-occlusive process involving numerous organs is now confirmed. In a multicenter study, 16 cases of "primary" APS (PAPS) were found and followed for 5 yr or more, all with renal biopsy. In all 16 cases of PAPS, there was a vascular nephropathy characterized by small vessel vaso-occlusive lesions associated with fibrous intimal hyperplasia of interlobular arteries (12 patients), recanalizing thrombi in arteries and arterioles (six patients), and focal cortical atrophy (10 patients). In combination, these led to progressive destruction of the kidney, accelerated by acute glomerular and arteriolar microangiopathy in five patients. Focal cortical atrophy is a distinctive lesion, present in 10 biopsies, and likely represents the histologic and functional renal analogue to the multiple cerebral infarcts detected on imaging studies. The clinical hallmark of this vascular nephropathy in PAPS is systemic hypertension, only variably associated with renal insufficiency, proteinuria, or hematuria. The ensemble of histologic renal lesions defined in this study should aid in the separation of the lesions found in cases of secondary APS, especially systemic lupus erythematosus, into those lesions related to APS and those related to the underlying disease.

Fibrinogen A alpha chain mutation (Arg554 Leu) associated with hereditary renal amyloidosis in a French family

A French family with hereditary renal amyloidosis (HRA) was studied. The disease presented in 7 of the 8 affected individuals with proteinuria or the nephrotic syndrome. The age of onset was in the fifth decade of life. There is currently no sign of extrarenal involvement in any affected individual. However, the nephropathy in this family is progressive and led to terminal renal failure in 4 patients. Immunohistochemistry studies of glomerular amyloid deposits suggested that the amyloid protein was the fibrinogen A alpha chain. Direct DNA sequencing revealed a G 4993 T transversion and subsequently Arg 554 Leu mutation in the fibrinogen A alpha chain. This is the first description of this fibrinogen A alpha chain mutation in Europe. This family is of French descent and cannot be related to the previously reported Peruvian/Mexican and African-American kindreds.

A novel variant of transthyretin (Glu42Asp) associated with sporadic late-onset cardiac amyloidosis

A sixty-three year old French man presented with isolated late-onset amyloid cardiomyopathy proven by endomyocardial biopsy. There was no known family history of amyloidosis. Immunohistochemistry of cardiac deposits suggested that amyloi fibrils were derived from transthyretin. DNA sequencing revealed a point mutation in exon 2 of the transthyretin gene responsible for a novel amyloidogenic variant Asp42.

Familial amyloid polyneuropathy type I (Portuguese): distribution and characterization of renal amyloid deposits

Renal amyloidosis has been considered rare and late in the evolution of the transthyretin (TTR) familial amyloid polyneuropathy (FAP) of the Portuguese type (type I). Renal biopsy has been performed systematically in 14 patients with FAP type I before liver transplantation. In all patients, TTR Met30 mutation was shown. Seven had proteinuria or abnormal microalbuminuria, whereas seven others had no urinary abnormalities. All had renal amyloid deposition predominantly in the medulla. Glomerular and vascular involvement was more prominent in patients with urinary abnormalities. Patients with the most extensive renal lesions represented a subgroup with a low score of polyneuropathy disability, a high prevalence of nephropathy in the proband generation, or a late onset for relatives with nephropathy. Immunohistochemistry studies showed that the amyloid substance corresponded to transthyretin. We have shown that renal TTR-derived amyloid deposition is common in patients with FAP type I, even in the absence of urinary abnormalities. The clinical presentation of nephropathy is not a late occurrence in the disease.

[Nephronophtisis in Senegal: first 3 cases]

Nephronophtisis is a familial tubulo-interstitial nephropathy with an autosomic recessive mode of transmission. To our knowledge, it has not been yet reported in Black Africa. We report here the case of a 17-year old female from Senegal who presented with renal failure related to a chronic interstitial nephritis characterized by polyuria, hypocalcemia, natriuresis of 23 mmol/l and serum creatinine level of 1070 mumol/l. The parents of this patient were first-degree cousins. Among the 6 siblings, 2 other males were found to have a renal disease. Ultrasound examination of the kidneys showed medullary cysts in the 2 affected brothers and the renal biopsy in one case showed tubular atrophy, with thickening of the basal lamina and an interstitial fibrosis without glomerular involvement. Molecular genetic analysis confirmed the diagnosis of nephronophtisis, with a homozygous deletion of the NPH1 region. In order to recognize this disease early in life, one has to look for it in patients with tubulo-interstitial nephritis, polyuria, childhood enuresia especially when it is associated with growth retardation or tetany. This case raises the issue of consanguinity and endogamy which are frequently encountered in Africa. It also extends the geographic and ethnic distribution of nephronophtisis, being the first cases reported Black Africans.

Renal amyloidosis with a frame shift mutation in fibrinogen aalpha-chain gene producing a novel amyloid protein

A French kindred with autosomal dominant hereditary renal amyloidosis was found to have a novel mutation in the fibrinogen Aalpha-chain gene. In this kindred, renal disease appeared early in life and led to terminal renal failure at an early age. Renal transplantation resulted in rapid destruction of the allograft by amyloid deposition within 2 years. Amyloid fibril protein isolated from a transplanted kidney was found to contain a novel, hybrid peptide of 49 residues whose N-terminal 23 amino acids were identical to residues 499 to 521 of normal fibrinogen Aalpha-chain. The remainder of the peptide (26 residues) represented a completely new sequence for mammalian proteins. DNA sequencing documented that the new sequence was the result of a single nucleotide deletion at position 4897 of the fibrinogen Aalpha-chain gene that gives a frame-shift at codon 522 and premature termination at codon 548. The contributions toward fibrillogenesis of the two portions of the amyloid fibril protein, ie, N-terminal fibrinogen sequence and C-terminal novel sequence, are presently unknown. However, the early onset and rapid reoccurrence of amyloid in renal transplants is unlike the clinical course with other amyloid proteins having single amino acid substitutions that give hereditary renal amyloidosis. Liver transplantation to stop synthesis of this abnormal hepatic derived protein should be considered early in the course of the disease.

[Treatment of von Hippel-Lindau disease with renal involvement]

OBJECTIVE

To try to define when and what type of operation should be performed in von Hippel-Lindau disease (VHL) with renal involvement.

MATERIAL AND METHODS

Between 1985 and July 1996, 43 patients with renal involvement of VHL disease were followed in our department. We decided to operate on patients with one or several solid or complex tumours greater than 2.5 cm in diameter, by means of conservative surgery (tumour excision removing a layer of healthy parenchyma) when the kidney did not contain more than 5 or 6 tumours or radical nephrectomy in the other cases. Subsequent follow-up consisted of CT, chest x-ray and renal function tests every 6 months.

RESULTS

Twenty-nine patients with a mean age of 33.6 years were operated. 21 patients (29 kidneys) were treated by conservative surgery: in situ in 20 cases and ex vivo in 9 cases; 3 cases were treated by bilateral radical nephrectomy, 4 by unilateral radical nephrectomy and 1 by resection of the prominent dome for urinary tract obstruction. Four cases of acute arterial thrombosis were observed following ex vivo surgery, requiring nephrectomy in every case. No serious complications were observed with in situ conservative surgery. A new lesion in the renal parenchyma remaining after conservative surgery was observed in 5 cases during follow-up (mean: 29 months). No local recurrence was observed after radical nephrectomy. Two nonoperated patients developed metastatic disease.

CONCLUSION

Conservative treatment is usually possible: either simple surveillance, in the absence of any solid or complex tumours larger than 2.5 cm in diameter, or conservative surgery for tumours larger than 2.5 cm in diameter, with no more than 6 tumours per kidney; this attitude requires six-monthly follow-up by CT of the renal parenchyma.