Malnutrition in patients with pressure ulcers: morbidity, mortality, and clinically practical assessments.

The association between protein-calorie malnutrition and pressure ulcers is well established. Measurements of nutritional status are frequently included in the routine clinical assessment of patients with pressure ulcers. This paper reviews the associations between these measurements and the presence, severity and healing of pressure ulcers.

The p53 gene in pediatric therapy-related leukemia and myelodysplasia.

We investigated the frequency of p53 mutations in 19 pediatric cases of therapy-related leukemia or myelodysplastic syndrome. Eleven children presented with acute myeloid leukemia, one with mixed-lineage leukemia, two with acute lymphoblastic leukemia, and five with myelodysplasia at times ranging from 11 months to 9 years after a primary cancer diagnosis. The primary cancers, which included 11 solid tumors and eight leukemias, were treated with various combinations of DNA topoisomerase II inhibitors, alkylating agents, or irradiation. Leukemic or myelodysplastic marrows were screened for possible mutations by single-strand conformation polymorphism (SSCP) analysis of p53 exons 4 to 8. The only observed mutation was an inherited 2-basepair deletion at codon 209 in exon 6 that would shift the open reading frame, create a premature termination codon, and foreshorten the resultant protein. Prior therapy in this patient included DNA topoisomerase II inhibitors, alkylating agents, and irradiation. The secondary leukemia presented as myelodysplasia with monosomies of chromosomes 5 and 7 and abnormalities of chromosome 17. Although the primary cancer was an embryonal rhabdomyosarcoma and there was a family history of cancer, the case did not fulfill the clinical criteria for Li-Fraumeni syndrome. This study suggests that germline p53 mutations may predispose some children to therapy-related leukemia and myelodysplasia, but that p53 mutations otherwise are infrequent in this setting.

p53 gene mutations in pediatric brain tumors.

We investigated the frequency of p53 mutations in 47 pediatric brain tumors of various histologic subtypes that were collected over a period of 5 years. The specimens included 15 primitive neuroectodermal tumors (PNETs), 17 low grade astrocytomas, one anaplastic astrocytoma, three glioblastomas (GBMs), one mixed glial tumor, eight ependymomas, one choroid plexus carcinoma, and one gangliocytoma/ganglioneuroma. Mutations were identified by single strand conformation polymorphism analysis of exons 4-8 and verified by sequencing. Mutations were present in 2 of 3 cases of GBM, but not in 17 low grade astrocytomas (P = 0.02, Fisher's exact test). One GBM demonstrated a germline GGC to AGC transition (gly to ser) at codon 245 with loss of the wild-type allele. A second GBM contained a CGG to TGG transition (arg to trp) at codon 248, also with loss of the wild-type allele, but normal tissue was not available for comparison. In addition, one of 15 PNETs retained heterozygosity but demonstrated a somatic CGT to TGT transition (arg to cys) at codon 273. p53 mutations were absent in other histologic subtypes and in two cases with multiple primary cancers. These data are consistent with earlier findings that p53 mutations are rare in PNETs, which are primarily pediatric tumors. In contrast to adult gliomas, p53 mutations in pediatric gliomas appear restricted to the GBMs. The lack of p53 mutations in pediatric low grade astrocytomas suggests not only histological differences, but also a different molecular pathogenesis in adult and pediatric patients.

Optimal staining and sample storage time for direct microscopic enumeration of total and active bacteria in soil with two fluorescent dyes.

Direct counting techniques, first developed for aquatic samples, can be used to enumerate bacteria in soil and groundwater sediments. Two fluorescent dyes, 5-cyano-2,3-ditolyl tetrazolium chloride (CTC) for actively respiring bacteria and 4(prm1),6-diamidino-2-phenylindole (DAPI) for total bacteria, were tested for their usefulness in epifluorescent direct bacterial enumeration in soil. Both dyes can be used for the same soil sample without affecting enumeration results. Staining for 8 h with CTC and for 40 min with DAPI resulted in maximum numbers of stained cells. The optimal DAPI staining concentration is 10 mg liter(sup-1). After preparation, slides should be stored at 4(deg)C and counted within 2 days for CTC and within 24 h for DAPI. Sodium PP(infi) or sodium chloride solutions were used to desorb bacteria from soil prior to counting. Counts were significantly higher when sodium chloride was used.

Complex replication error causes p53 mutation in a Li-Fraumeni family.

We demonstrated a germline p53 replication error in two generations of a Li-Fraumeni family affected with liposarcoma, adrenocortical carcinoma, and osteosarcoma. The trinucleotide repeat mutation changed 5'-AGT GTG GTG GTG-3' at codons 215-218 to 5'-AGT TGG TTG GTG GTG-3'. The predicted protein would be elongated by one amino acid (val216-->trp leu) without a change in charge. Detection of p53 in the adrenal tumor by immunostaining suggested that the mutant protein was expressed. Persistence of the mutation in the germline may suggest a defect in DNA repair in the family member first affected. This is the first report where germline transmission of replication-damaged p53 trinucleotide repeats is associated with the Li-Fraumeni syndrome.

A novel germline p53 splicing mutation in a pediatric patient with a second malignant neoplasm.

A novel germline p53 splicing mutation was identified in a pediatric patient with two metachronous primary cancers that are constituent tumors of the Li-Fraumeni syndrome. Genomic DNA from the second tumor showed the same mutation and loss of heterozygosity at the p53 locus. The mutant mRNA and protein were present in the tumor tissue. In contrast, in the normal tissues bearing the germline mutation in the heterozygous state, predominantly normal mRNA was expressed and the mutant p53 protein was not detectable. The functional silence and relative lack of mutant p53 mRNA expression in the normal tissues of this patient may be caused by decreased stability or decreased production. If this proves a more general pattern of expression of mutant p53 in individuals with germline mutations, these findings may explain the paucity of tumors in individuals affected with the Li-Fraumeni syndrome.