Non-tuberculous mycobacterial infection of the parotid gland in an immunosuppressed adult.

Infections of the parotid gland with non-tuberculous mycobacteria (NTM) are rarely described. Here, we report on an infection of the parotid gland caused by Mycobacterium avium and give a literature-based overview about this entity. In the light of a global increase of mycobacterial infections, unusual manifestations have to be considered and should be included in the differential diagnosis when dealing with solid lesions of uncertain aetiology in the head and neck region.

Molecular lesions in colorectal cancer: impact on prognosis? Original data and review of the literature.

BACKGROUND: In the Dukes' B and C stages of colorectal carcinoma there are considerable variations in the observed courses of the disease. Since post-operative chemotherapy in patients with Dukes' C (node-positive) colon carcinoma has been demonstrated to be effective in improving overall-survival, a more exact prognosis assessment gains additional significance and therapeutic relevance. DISCUSSION: One also hopes to derive improved prognostic factors from the clarification of the molecular pathogenesis. Because of its frequency and the accessibility and recognizability of its developmental stages colorectal carcinoma is among the best investigated of all solid tumors. Despite a multitude of suggested molecular candidate markers none of these changes has yet been able enter the everyday life of the clinic. However, it is to be expected that some of the molecular alterations presently discussed will gain importance before long in the clinical treatment of patients with colorectal carcinoma. CONCLUSION: Considering also our own findings, this review presents the latest developments in the scientific discussion of the tumor suppressor/oncogenes p53, k-ras, and DCC, biochemical determinants of the 5-fluorouracil metabolism, and defects of the DNA repair system.

Quantitative determination of Fcgamma receptor genes by means of fluorescence-based real-time polymerase chain reaction.

The granulocyte antigens HNA-1a, -1b and -1c reside on the FcgammaIIIb receptor, which is exclusively expressed on neutrophils. They are involved in autoimmune and alloimmune neutropenias as well as in severe transfusion reactions. Recent family studies show the HNA-1c antigen to be inheritably linked to HNA-1a, resulting in individuals carrying three genes. Using sequence-specific primers, the HNA antigens can be discerned in a polymerase chain reaction (PCR), but not the number of coding FCGR3B genes present in each individual. Therefore a real-time kinetic PCR method using the LightCycler technique was established to ascertain the amount of FCGR3B genes in each individual. For this purpose, the FCGR3B genes of four HNA-1a,-1b,-1c (+), one HNA-1b,1c (+) and one HNA-1b (+) individual were quantified. In addition, two families, in which the mother was FCGR3B deficient, were analyzed. Quantification showed two of the four HNA-1a,-1b and-1c (+) individuals to have three genes and the other two to have only two genes. The HNA-1b,-1c (+) individual had also only two genes. As expected, the HNA-1b donor was typed for two genes. No FCGR3B genes could be detected in the FCGR3B-deficient mothers of either family; their husbands however, carried two FCGR3B genes. Accordingly, quantitative PCR showed the offspring of both families to have only one FCGR3B gene. Quantitative PCR with the Light Cycler has been revealed to be a fast and reliable method for the determination of FCGR3B genes present. FCGR3B quantification confirms the idea of the HNA-1c antigen to be inherited not only linked to HNA-1a, but also to be passed down on its own.

HNA-1a, HNA-1b, and HNA-1c (NA1, NA2, SH) frequencies in African and American Blacks and in Chinese.

The granulocyte antigens HNA-1a, -1b, and -1c (formerly named NA1, NA2 and SH) which reside on the neutrophil FcgammaReceptor IIIb (FcgammaRIIIb) play a major role in immune neutropenias and pulmonary transfusion reactions. In an attempt to shed some light on the origin and history of these antigens we typed the DNA of Blacks from South Africa (n=99), and Ghana (n=27), of 56 African Americans, and of 138 Chinese from Taiwan for HNA-1a,-1b, and -1c antigens using polymerase chain reaction with sequence-specific primers (PCR-SSP). In African and American Blacks, the HNA-1b antigen was more frequent than HNA-1a (77 vs. 67% and 77 vs. 59%, respectively). In contrast, in Chinese HNA-1a was more frequent than HNA-1b (91 vs. 54%). We observed 3 individuals with FcgammaRIIIB deficiency among the 126 tested African Blacks indicating a higher frequency of FcgammaRIIIB deficiency in Blacks than the reported 0.1% in Europeans. In addition, the frequency of HNA-1c in African and American Blacks (38 and 23%, respectively) was higher than the reported 5% in Europeans. Among the 57 HNA-1c (+) Blacks, all were HNA-1b (+) but only 26 were HNA-1a (+) supporting the idea that the HNA-1c antigen is the result of an additional point mutation in the allele coding for HNA-1b. Recently, HNA-1a, -1b, and -1c (+) Europeans have been reported to have three distinct FcgammaRIIIB genes. Among 26 Blacks who had been typed HNA-1a,b,c (+) by PCR-SSP we identified only 7 having three FcgammaRIIIB genes by DNA sequencing. When we sequenced the DNA of 6 HNA-1a,b,c (+) Europeans we found 4 of the individuals had three FcyRIIIB genes. Therefore, we assume that in Africa the point mutation occurred first in the HNA-1b allele resulting in the HNA-1c allele and the FcgammaRIIIB gene duplication took place later.