Genetics and phenotypic characteristics of autosomal dominant polycystic kidney disease in Finns

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease, leading to renal insufficiency and renal transplantation. Mutation screening in the major gene for ADPKD, the polycystic kidney disease type 1 (PKD1) gene, has often been incomplete because of multiple homologous copies of this gene elsewhere on chromosome 16. Furthermore, there are only a few studies investigating genotype–phenotype correlations in patients with ADPKD. In this study, we screened the entire coding region of the PKD1 and PKD2 genes in 17 Finnish families with ADPKD via long-range polymerase chain reaction, single-strand conformation polymorphism analysis, and direct sequencing. We were able to identify mutations co-segregating with ADPKD in all 16 families linked to PKD1 by haplotype analysis. Of these mutations, six were insertions/deletions, five nonsense mutations, and five missense mutations. In the only PKD2-linked family, we found a missense mutation, R322Q. With the exception of one mutation (L845S in PKD1), all mutations were novel. Mutations and their location did not have a strong correlation with the phenotype with the exception of subarachnoidal hemorrhage or brain aneurysm, where mutations were located more often at the 5 end of the PKD1 gene than at the 3 end of the PKD1 gene.Electronic Supplementary Material Supplementary material is available for this article at .     

Diagnosis of Mycoplasma pneumoniae Pneumonia in Children

We evaluated a commercial immunoglobulin M (IgM)-capture immunoassay for the detection of Mycoplasma pneumoniae infections in 278 pediatric patients with community-acquired, radiographically defined pneumonia. Acute- and convalescent-phase serum samples were collected from all patients and were tested for M. pneumoniae-specific IgM and IgG antibodies by Platelia enzyme immunoassays (Sanofi Diagnostica Pasteur, Marnes la Coquette, France). Nasopharyngeal aspirates (NPAs) were collected at the time of admission to the hospital. A total of 227 NPAs were subjected to the detection of M. pneumoniae DNA by PCR, and 191 NPAs were cultured by using the Pneumofast kit (International Mycoplasma, Signeswere, France). Southern hybridization of PCR products and the IgM test with solid-phase antigen (Serion Immunodiagnostica, Würzburg, Germany) were used for additional confirmation of a positive result, which required agreement of at least two different methods. A total of 24 (9%) confirmed diagnoses of mycoplasma infection were made, 5 (21%) of which were in children <5 years of age. Of the positive children, 24 of 24 (sensitivity, 100%) were positive by the IgM-capture test with convalescent-phase serum, 19 of 24 (79%) were positive by the IgM-capture test with acute-phase serum, 19 of 24 (79%) were positive by IgG serology, 10 of 20 (50%) were positive by PCR, and 8 of 17 (47%) were positive by culture. An additional 5 (of 254) children were positive by the Platelia IgM test alone (specificity, 98%). When the PCR with Southern hybridization result was combined with the IgM-capture test result with the acute-phase sera, the sensitivity of rapid laboratory diagnosis increased to 95%. In conclusion, the IgM serology test was the single most valuable tool for the diagnosis of M. pneumoniae pneumonia in children of any age.     

Cell-specific regulation of gamma-glutamylcysteine synthetase in human interstitial lung diseases

The pathogenesis of interstitial lung diseases (ILDs) is known to be associated with reactive oxygen and nitrogen metabolites and increased oxidant stress. One of the major antioxidants in human lung is glutathione (GSH) and enzymes linked to its synthesis. The rate-limiting enzyme of GSH synthesis is gamma-glutamylcysteine synthetase (γ-GCS) containing catalytically active heavy (γ-GCSh) and regulatory light (γ-GCSl) subunits. It can be hypothesized that γ-GCS is the major determinant in explaining reduced GSH levels in fibrotic lung disorders. We investigated the regulation of γ-GCS by transforming growth factor beta₁ (TGF-β₁) and tumor necrosis factor alpha (TNF-α) in human lung cells and its expression and distribution in fibrotic (biopsy-proven idiopathic pulmonary fibrosis, for instance, usual interstitial pneumonia, UIP, n = 15), inflammatory, and granulomatous diseases of human lung parenchyma (desquamative interstitial pneumonia, n = 10; ILD associated with collagen diseases, n = 10; sarcoidosis, n = 19 and allergic alveolitis, n = 8). In human lung alveolar epithelial cells, γ-GCSh was decreased by TGF-β₁, whereas TNF-α caused a transient enzyme induction. In normal lung, γ-GCS was mainly localized to the bronchiolar epithelium. In UIP, the highest immunoreactivities were observed in the airway epithelium and metaplastic alveolar epithelium, but fibroblastic foci were negative. In sarcoidosis, the highest reactivities were detected in the epithelium, alveolar macrophages and pulmonary granulomas. γ-GCS was ultrastructurally localized to the cytoplasm of regenerating type II pneumocytes and macrophages. In conclusion, γ-GCS is widely expressed in sarcoidosis and regenerating epithelium but is low in the fibrotic areas of usual interstitial pneumonia, probably because of enzyme down-regulation.     

Severe reactions from roe without concomitant fish allergy.

BACKGROUND: Although fish allergy is common, no studies have been published on allergy to fish roe. OBJECTIVE: To describe 2 cases of IgE-mediated allergy to 2 roe species. METHODS: Two patients, one with local symptoms and the other with anaphylaxis following ingestion of roe, underwent skin prick testing (SPT) with 2 roe species, whitefish roe (WFR) and rainbow trout roe (RTR). Serum samples were taken for IgE measurement and immunoblotting to identify roe allergens. Inhibition studies were performed to scrutinize the cross-reactivity between the roes and to fish. RESULTS: The results of the SPTs with the roes were clearly positive in both patients but negative in control persons. The results of SPTs to all other foods were negative. Roe-specific IgE levels were elevated in the serum samples of both patients. Immunoblotting revealed different IgE-binding patterns of the extracts and different inhibition profiles with the serum samples. In WFR blotting, both serum samples detected a heavy IgE-binding band at approximately 20 kDa, which was not inhibited with fish. Cross-reactivity between the roes was demonstrated in the patient with local symptoms from RTR but not in the patient with anaphylaxis from WFR. The first serum sample also detected several IgE-binding bands in the RTR blot, the most intensive at 21 to 23 kDa and 30 kDa, which were partially inhibited by WFR and more completely with fish. The anaphylaxis patient did not detect allergens in the RTR blot. After the investigation, the patients have remained symptom free and able to consume all kinds of fish without problems. CONCLUSIONS: IgE-mediated allergy to roe is possible without concomitant fish allergy. Roe allergy should be explored in patients who test negative to fish but are suspected of having seafood-related allergy.     

Hyaluronan expression in differentiated thyroid carcinoma.

The extracellular polysaccharide hyaluronan (HA) controls cell migration, differentiation, and proliferation, and is supposed to contribute to the spreading of several human cancers. Little is known about the role of HA in the development and progression of differentiated thyroid carcinoma (DTC). The expression and prognostic value of HA were therefore evaluated in 204 consecutive patients with DTC. A biotinylated affinity probe specific for HA was applied to paraffin-embedded tumour samples to assay the expression of HA in carcinoma cells and in intra/peritumoural stroma. In a majority of the samples, a high percentage (>or=90%) of normal thyroid follicle epithelial cells were HA-positive. This high percentage was also found in 80 (47%) papillary carcinomas, but only in seven (21%) follicular carcinomas (p=0.004). Age (>60 years) of the patients was significantly associated with a low percentage of HA-positive cancer cells (p=0.013). Cancer cell-associated HA correlated significantly with the percentage of cells expressing total CD44 and its isoforms containing exons v3 and v6 (r=0.223-0.289, p<0.001 for all). The tumour stroma was always positive for HA. Stromal staining intensity did not differ markedly between papillary and follicular carcinomas. A strong stromal HA staining intensity was related to distant metastases (p=0.044), high pTNM stage (p=0.024), old age (>60 years) (p=0.043), and cancer-related mortality (p=0.001). In a log-rank univariate survival analysis, strong stromal HA staining intensity was related to DTC mortality (p=0.0007). Cancer cell-associated HA expression did not significantly correlate with patient survival. In Cox's multivariate survival analysis, age (>60 years, p=0.0164), gender (p=0.0251), and pTNM stage (p=0.0121) were significant independent prognostic factors for DTC-related death. These results suggest that strong stromal HA staining intensity is related to progression and unfavourable outcome in DTC patients, while the clinical factors remain more powerful in predicting DTC-related death.     

Innate immunity in experimental SIV infection and vaccination

Innate immunity represents the first line of defence to pathogens besides the physical barrier and seems to play a role in protection against HIV/SIV infection and disease progression. High production of beta-chemokines and CD8+ T cell anti-viral factors in naive as well as in vaccinated macaques has been associated with complete or partial protection against SIV infection indicating that genetic or environmental factors may influence their production. This innate immunity may help in generating HIV/SIV-specific responses upon the first exposure to HIV/SIV. SIV subunit vaccines given by the targeted iliac lymph node route have been shown to induce an increased production of CD8+ T cell suppressor factors and beta-chemokines. Only a few vaccine studies have focused on enhancing the innate immune response against HIV/SIV. The use of unmethylated CpG motifs, HSP and GM-CSF as adjuvants in SIV vaccines has been shown to induce production of HIV/SIV-inhibiting cytokines and beta-chemokines, which seem to be important in modulating and steering the adaptive immune responses. HSP has also been shown to induce gammadelta+ T cells, which contribute to the innate immunity. More knowledge about the interplay between the innate and adaptive immune responses is important to develop new HIV/SIV vaccine strategies.     

Epidermal cell culture model derived from rat keratinocytes with permeability characteristics comparable to human cadaver skin.

The permeability characteristics of an organotypic epidermal culture model derived from rat epidermal keratinocytes, ROC, and isolated human cadaver epidermis, HEM, were compared. Rat epidermal keratinocyte (REK) cell line was grown for 3 weeks on collagen gel in the absence of feeder cells in culture inserts at an air-liquid interface. Transdermal permeabilities of 18 compounds ranging from 92 to 504 in molecular weight and from -4.3 to 3.9 in log of octanol-water partition coefficient, charged or uncharged, were measured in the culture model and isolated human epidermis. The REK organotypic culture model (ROC) provided a close estimate of human epidermal permeabilities over the whole range of the solutes used with on the average of 2-fold higher permeability coefficients (range 0.3-5.2) than those obtained from isolated human cadaver epidermis. The easily maintained and reproducible ROC model may be useful in screening transepidermal drug permeabilities together with possessing potential for research on dermal formulations, irritation, toxicity and gene therapy.     

Executive functions and speed of mental processing in elderly patients with frontal or nonfrontal ischemic stroke

Impairments in executive functions have been related to aging and frontal lobe lesions. Aging also causes slowing of mental processing. We examined whether ischemic stroke in the frontal brain area results in dysexecutive syndrome, or whether the frontal stroke causes increased slowing of mental processing. Neurological, radiological and neuropsychological examinations were carried out 3 months post-stroke on 250 ischemic stroke patients (55-85 years) and on 39 healthy control subjects. Of the patients, 62 had frontal and 188 had nonfrontal lesions. The neuropsychological examination comprised several cognitive domains, including tests considered to measure executive functions. The frontal group was slower than the nonfrontal group in tasks measuring speed of mental processing which were time-limited (Trail Making A, Stroop dots and fluency). They were also inferior in the Digit Span backwards task. There were no differences between the groups in other cognitive domains, nor in some tests which are considered to be measures of executive functions (e.g. WCST). Impairments in executive functions were evident in both the frontal and the nonfrontal groups compared with the controls, but no dysexecutive syndrome specifically related to frontal lesions was found. Frontal stroke related mainly to the slowing of mental processing.