PubMed Health⌕ Search

Biomedical subjects

Daniel Bak

Publications and source records attributed to Daniel Bak.

5 recordsLinked to original sources

Analysis of CFTR, SPINK1, PRSS1 and AAT mutations in children with acute or chronic pancreatitis.

OBJECTIVES: Defects of PRSS1, SPINK1, CFTR and AAT are considered causative or predisposing to pancreatitis. The aim of this study was to evaluate the impact of these defects into molecular pathology of chronic pancreatitis (CP) and acute recurrent pancreatitis (ARP). METHODS: Ninety-two children with CP or ARP, 55 family members and 50 controls were investigated. The subjects were screened for PRSS1 mutations: R122H, R122C, A16V, N29I; SPINK1 N34S variant; panel of 14 CFTR defects: INNOLiPA CFTR12, CFTRdele2,3 and IVS8-T variant or panel of 3 CFTR defects-F508del, CFTRdele2,3 and IVS8-T; AAT mutations: E264V, E342K. RESULTS: We identified 1 mutated allele in at least 1 of 4 genes in 31 of 92 patients and 12 of 50 controls (P = 0.157). Mutations in SPINK1 and PRSS1 were most frequent. PRSS1 mutations were identified mainly in CP patients (9.6% of CP vs 2.5% of ARP alleles, P = 0.094), whereas N34S SPINK1 mutation was present with comparable frequency in CP and ARP patients (7.7% vs 10.0%, P = 0.768). The frequency of mutations in CFTR alleles was similar to controls (4.9% vs 5%, P = 0.587). Overall frequency of AAT mutations was lower than in the controls. Family studies showed that defects in the examined genes did not always segregate with disease. CONCLUSIONS: PRSS1 defects seem to be causative for pancreatitis, whereas defects in SPINK1 are suggested to be associated with the disease. No association between CFTR mutations and pancreatitis was observed. The importance of AAT variants remains speculative.

Acute Disease↗

Molecular analysis of defects in the CFTR gene and AZF locus of the Y chromosome in male infertility.

OBJECTIVE: To investigate the frequency and potential impact of mutations and polymorphisms in the CFTR gene and deletions in AZF locus of the Y chromosome in patients with azoospermia (AZOO), cryptozoospermia (CRYPTO) or oligoasthenoteratozoospermia (OAT) who were to be included in an assisted reproductive technologies (ART) program. STUDY DESIGN: A total of 188 infertile men were enrolled in the study: 100 patients with AZOO, 38 with CRYPTO and 50 with OAT. RESULTS: The CFTR gene mutations or IVS8-5T variant in at least 1 allele was identified with similar frequencies among the AZOO (33%) and CRYPTO (21%) patients; 55% of the AZOO patients with normal spermatogenesis (NS) had mutations in 1 or 2 alleles. The novel R810G mutation in exon 13 was identified in 1 NS patient. The OAT or AZOO patients with Sertoli cell only syndrome (SCO) had mutations in the CFTR gene with similar frequencies to that in the general Polish population. The deletions in the AZF locus were detected in 20% of SCO patients, 11.5% of AZOO patients with maturation arrest and in 5% of CRYPTO patients. The other groups (NS, OAT) did not carry deletions in the region studied. CONCLUSION: Molecular diagnosis of the CFTR gene, Y chromosome deletion analysis and genetic counseling are necessary diagnostic elements for patients with male infertility, especially if the are included in an ART program.

Adult↗

[Diseases associated with protein aggregation].

The so-called conformational diseases constitute a specific subtype of protein folding diseases that is characterized by abnormal aggregation of improperly folded polypeptides. This review describes a series of examples of such disorders and summarizes the present knowledge on their molecular pathophysiology and new therapeutic strategies.

Alzheimer Disease↗

[Hereditary aspects of pancreatitis].

Pancreatitis presents clinically as acute and chronic form. A common characteristic of these two forms is enzymatic autodigestion of pancreas in the course of the disease. It results from premature activation of pancreatic digestive enzymes and disturbance of subtle balance between proteolytic enzymes and their inhibitors. The way to understand the character of mechanisms leading to development of pancreatitis has been simplified by discovery of genetic factors, which are able to initiate pathological changes at tissue level. Mutations in the PRSS1 gene (first of all R122H and N29I mutations), which encodes for cationic trypsin, cause trypsin to be protected from autodegradation. These mutations also cause precursor of trypsin - trypsinogen, to be activated easier. On the other hand mutations in the SPINK1 gene have been identified. SPINK1 gene encodes for the most important protease inhibitor of the pancreatic fluid. The most frequent mutation, namely N34S, decrease SPINK1 protein in its activity. The link between the genotype and phenotype is not clear in every case. It is probable that pancreatitis will be recognized as poligenic with many genes engaged in the disease development. Pancreatic cancer is a frequent consequence of pancreatitis. It is a very invasive cancer with high mortality. In the course of pancreatic inflammation intensive cell proliferation takes place for regeneration of pancreas damage. It is the chance for amplification of pathological changes in DNA, which have arisen as a ROS's (Reactive Oxygen Species) and RNOS's (Reactive Nitrogen Oxide Species) action effect. ROS and RNOS are generated in the course of pancreas inflammation.

Genetic Predisposition to Disease↗