Case reports of nocardiosis in patients with human immunodeficiency virus (HIV) infection

INTRODUCTION

We present 4 local cases of nocardiosis in HIV-infected patients and discuss the diagnosis, clinical syndromes and therapy of nocardiosis.

CLINICAL PICTURE

Two cases presented with pulmonary nocardiosis, one had a cervical lymph node abscess and one had disseminated nocardiosis with pulmonary, cerebral and soft tissue involvement.

TREATMENT

Combination therapy is often employed. Sulphonamides or co-trimoxazole, amikacin, imipenen, minocycline and ceftriaxone are some of the drugs that could be used.

OUTCOME

Outcome hinges on the early recognition and optimal treatment of this infection.

CONCLUSIONS

Clinical presentations vary and diagnosis is difficult and frequently delayed. Nocardiosis should be suspected in patients who present with pulmonary lesions with soft tissue and/or cerebral abscesses.

Simple bone cyst in cervical vertebral spinous process and laminae: report of a case

Simple (unicameral or solitary) bone cysts are the only true cysts of primary intraosseous origin. These cysts involve the metaphysis of long tubular bones such as the proximal humerus and proximal femur and, occasionally, the proximal tibia, distal femur, patella, ilium, rib, and calcaneus. They are very rarely found in vertebrae, especially in the cervical vertebral spinous process and laminae. We report a 14-year-old boy with an expansile, bubbly cystic lesion in the spinous process and laminae of the seventh cervical vertebra. Histopathologic examination showed a cyst surrounded by thin fibrous or fibro-osseous wall without any lining epithelial cells, compatible with a simple bone cyst. As far as we know, this is the first case of simple bone cyst involving the spinous process and laminae of a cervical vertebra reported in Taiwan.

Insertion/deletion mutations of type I oculocutaneous albinism in chinese patients from Taiwan

Type I oculocutaneous albinism (OCA1) is an autosomal recessive disorder, which is caused by the reduction or the absence of tyrosinase activity in melanocytes of the skin, hair and eyes. Although tyrosinase mutations of OCA1 have been extensively analyzed in most populations worldwide, there is no systemic study of OCA1 mutation in Chinese patients. By use of single strand conformation polymorphism and direct sequencing, we had detected 21 mutant alleles out of 24 OCA1 chromosomes screened (87.5%). Detected mutant alleles include one splicing site, three insertion/deletion and five missense mutations, of which the splicing site nucleotide alteration (IVS 1-3C>G) and two each of the insertion/deletion (232-233 ins GGG and 861-862 del TT) and missense mutations (Cys 289 Gly and Trp 400 Leu) are novel. The ins/del mutations accounts for about 37.5% in Chinese OCA1 alleles. The 232-233 ins GGG, one of the novel mutations, was found to be most frequent (25%) among the OCA1 alleles in Chinese. Through this study, we found that while some of the OCA mutant alleles were identified in other populations, ethnic difference still exists. Hum Mutat 14:542, 1999.

Human FRAG1 encodes a novel membrane-spanning protein that localizes to chromosome 11p15.5, a region of frequent loss of heterozygosity in cancer

We have previously identified a chromosomal rearrangement between fibroblast growth factor receptor 2 (FGFR2) and a novel gene, FRAG1, in a rodent model of osteosarcoma. To assess the potential role of FRAG1 in disease further, we have isolated cDNA and genomic clones of human FRAG1. Sequence analysis of the cDNA revealed the presence of an insertion not contained in the original FRAG1 sequence. This insertion in human FRAG1 encoded a region highly homologous to and immediately following the first 55 amino acids of the protein, indicating the presence of a repetitive domain within FRAG1, designated the FRAG1 homology (FH) domain. Analysis of FRAG1 gene structure revealed that the FH domains were encoded by tandem duplicated exons. Database searches identified several transmembrane proteins displaying homology to the FH domain of FRAG1. In addition, hydropathy analysis predicted FRAG1 to encode an integral membrane protein with multiple membrane-spanning segments. FRAG1 mRNA was ubiquitously expressed in human adult tissues and several tumor cell lines at varying levels of abundance. Human FRAG1 was mapped by fluorescence in situ hybridization and radiation hybrid analysis to chromosome 11 at band p15.5, a region implicated in Beckwith-Wiedemann syndrome and a region of frequent loss of heterozygosity in multiple tumor types. These results suggest that FRAG1 may be a useful candidate gene for genetic disorders associated with alterations at 11p15.5.

Identification, mapping, and genomic structure of a novel X-chromosomal human gene (SMPX) encoding a small muscular protein

Reciprocal probing has been used to identify a cDNA clone (xh8H11) representing a gene preferentially expressed in striated muscle. The gene maps close to DXS7101 31.9 cM from the short arm telomere of the X-chromosome at Xp22.1. On searching expressed and genomic databases, 21 expressed sequence tags were found that allowed the assignment of a human extended consensus sequence of 887 bp, suggesting a completely expressed gene symbolized as SMPX. By using the human consensus sequence, the orthologous mouse Smpx and rat SMPX genes could be aligned and confirmed by complete sequencing of additional SMPX-related clones obtained by library screening. An open reading frame was identified encoding a peptide of 88-86 and 85 amino acids in human and rodents, respectively. The predicted peptide had no significant homologies to known structural elements. The human consensus cDNA sequence was used to define the genomic structure of the human SMPX that had been missed by a previous large scale sequencing approach. The gene consists of five exons (> or =172, 57, 84, 148, > or =422 bp) and four introns (3639, 10410, 6052, 31134 bp) comprising together 52.1 kb and is preferentially and abundantly expressed in heart and skeletal muscle. Thus, a novel human gene encoding a small muscular protein that maps to Xp22.1 (SMPX) has been identified and structurally characterized as a basis for further functional analysis.

Axenic aerobic biofilms inhibit corrosion of copper and aluminum

The corrosion behavior of unalloyed copper and aluminum alloy 2024 in modified Baar's medium has been studied with continuous reactors using electrochemical impedance spectroscopy. An axenic aerobic biofilm of either Pseudomonas fragi K or Bacillus brevis 18 was able to lessen corrosion as evidenced by a consistent 20-fold increase in the low-frequency impedance value of copper as well as by a consistent four- to seven-fold increase in the polarization resistance of aluminum 2024 after six days exposure compared to sterile controls. This is the first report of axenic aerobic biofilms inhibiting generalized corrosion of copper and aluminum. Addition of the representative sulfate-reducing bacterium (SRB) Desulfovibrio vulgaris (to simulate consortia corrosion behavior) to either the P. fragi K or B. brevis 18 protective biofilm on copper increased the corrosion to that of the sterile control unless antibiotic (ampicillin) was added to inhibit the growth of SRB in the biofilm.

Outbreak of Nipah-virus infection among abattoir workers in Singapore

BACKGROUND

In March 1999, an outbreak of encephalitis and pneumonia occurred in workers at an abattoir in Singapore. We describe the clinical presentation and the results of investigations in these patients.

METHODS

Clinical and laboratory data were collected by systemic review of the case records. Serum and cerebrospinal fluid (CSF) samples were tested for IgM antibodies to Nipah virus with an IgM capture ELISA. Reverse-transcriptase PCR was done on the CSF and tissue samples from one patient who died.

FINDINGS

Eleven patients were confirmed to have acute Nipah-virus infection based on raised IgM in serum. Nipah virus was identified by reverse transcriptase PCR in the CSF and tissue of the patient who died. The patients were all men, with a median age of 44 years. The commonest presenting symptoms were fever, headache, and drowsiness. Eight patients presented with signs of encephalitis (decreased level of consciousness or focal neurological signs). Three patients presented with atypical pneumonia, but one later developed hallucinations and had evidence of encephalitis on CSF examination. Abnormal laboratory findings included a low lymphocyte count (nine patients), low platelet count, low serum sodium, and high aspartate aminostransferase concentration (each observed in five patients). The CSF protein was high in eight patients and white-blood-cell count was high in seven. Chest radiography showed mild interstitial shadowing in eight patients. Magnetic resonance imaging (MRI) showed focal areas of increased signal intensity in the cortical white marker in all eight patients who were scanned. The nine patients with encephalitis received empirical treatment with intravenous aciclovir and eight survived.

INTERPRETATION

Infection with Nipah virus caused an encephalitis illness with characteristic focal areas of increased intensity seen on MRI. Lung involvement was also common, and the disease may present as an atypical pneumonia.

Modulation of synaptic transmission and differential localisation of mGlus in cultured hippocampal autapses

Metabotropic glutamate receptors (mGlus) are known to modulate synaptic transmission in various pathways of the central nervous system, but the exact mechanisms by which this modulation occurs remain unclear. Here we utilise electrophysiological and immunocytochemical techniques on cultured autaptic hippocampal neurones to investigate the mechanism of action and distribution of mGlus. Agonists at all three groups of mGlus depressed glutamatergic transmission, whereas only agonists at group I mGlus depressed GABAergic transmission. Agonists at all mGlus failed to modulate Ca2+ and K+ channels in glutamatergic autapses whereas an agonist at group III mGlus did depress the frequency of miniature excitatory postsynaptic currents (mEPSCs). Agonists failed to modulate Ca2+ or K+ channels and miniature inhibitory postsynaptic currents (mIPSCs) in GABAergic autapses. Distribution studies using selective antibodies revealed punctate staining for group III mGlus that co-localised with the synaptic marker, synaptophysin. Staining for the remaining mGlus was more diffuse throughout the soma and processes with little co-localisation with synaptophysin. The distribution of the group III receptors is consistent with the direct 'downstream' modulation of mEPSCs, although the exact mechanism of action for the remaining receptors remains unclear.

Influence of surface roughness on the calculation of optical constants of a metallic film by attenuated total reflection

The measured optical-constant errors that arise in the Kretschmann configuration from surface roughness have been analyzed. The broadening of the half-width and the change in the reflection minimum of the attenuated-total-reflection curve that are due to the surface roughness are described. Calculation of the correct optical constants and silver-film thickness is demonstrated.

Prenatal diagnosis of partial trisomy 3p(3p23-->pter) and monosomy 7q(7q36-->qter) in a fetus with microcephaly alobar holoprosencephaly and cyclopia

We report the prenatal diagnosis of partial trisomy 3p(3p23-->pter) and monosomy 7q(7q36-->qter) in a fetus with microcephaly, alobar holoprosencephaly and cyclopia. A 26-year-old primigravida woman was referred for genetic counselling at 23 gestational weeks due to sonographic findings of intra-uterine growth retardation and cranio-facial abnormalities. Level II ultrasonograms further demonstrated alobar holoprosencephaly, a proboscis above the eye and a single median orbit consistent with cyclopia. Genetic analysis and fluorescence in situ hybridization on cells obtained from amniocentesis showed distal 3p trisomy (3p23-->pter) and 7q36 deletion, 46,XX,der(7)t(3;7)(p23;q36), resulting from a paternal t(3;7) reciprocal translocation. The pregnancy was terminated. Autopsy further confirmed the presence of arrhinencephaly, agenesis of the corpus callosum and a single ventricle of the brain. The phenotype of this antenatally diagnosed case is compared with those observed in 10 previously reported cases with simultaneous occurrence of partial trisomy 3p and terminal deletion 7q. All cases are associated with severe forms of holoprosencephaly and facial dysmorphism. This delineates an autosomal imbalance syndrome or a dosage effect involving duplication of distal 3p/deficiency of terminal 7q and dysmorphogenesis of the forebrain and mid-face.

Reduced expression of the CDK inhibitor p27(KIP1) in rat two-stage bladder carcinogenesis and its association with expression profiles of p21(WAF1/Cip1) and p53

The cyclin-dependent kinase (CDK) inhibitor p27(KIP1) exerts its growth suppressive effects by targeting the cyclin-CDK complexes. Reduced protein levels of p27(KIP1) have been reported in numerous human cancers and this has been attributed to increased degradation. However, few reports have addressed the significance of p27(KIP1) expression in chemical carcinogenesis of rodents. In a rat two-stage urinary bladder carcinogenesis model, with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) initiation followed by promotion with sodium L-ascorbate (Na-AsA), we evaluated the expression of p27(KIP1) protein using immunohistochemistry during various stages of urinary bladder carcinogenesis. In addition, we evaluated the mRNA expression profiles for p27(KIP1), p21(WAF1/Cip1) and p53 in tumors. Fisher 344 rats were initiated with 0.05% BBN in the drinking water for 4 weeks and then administered 5% Na-AsA in the diet. Immunohistochemical examination revealed p27(KIP1) protein to be constitutively expressed in normal urothelium, simple hyperplasia and in most papillary and nodular (PN) hyperplasias and small papillomas, but diminished or absent in large papillomas and in transitional cell carcinomas. An inverse correlation between expression of p27(KIP1) and cell proliferation was generally observed. Quantitation of mRNA by multiplex reverse transcription-PCR showed a significant downregulaton of p27(KIP1), p21(WAF1/Cip1) and p53 mRNA in tumors. More than 50% reduction in p27(KIP1) mRNA expression was observed in 42 and 47% of tumors at weeks 18 and 24, respectively; similar reduction in p21(WAF1/Cip1) mRNA expression was observed in 58 and 73% of tumors at weeks 18 and 24, and in p53 mRNA expression in 50 and 73% of tumors at weeks 18 and 24, respectively. None of the 25 tumors we examined by PCR-single-strand conformational polymorphism analysis had p53 mutations. These data imply that abnormal down-regulation of p27(KIP1), p21(WAF1/Cip1) and/or p53 in tumor cells may contribute to the malignant progression of tumors during rat two-stage bladder carcinogenesis.

Assessment of functional MR imaging in neurosurgical planning

BACKGROUND AND PURPOSE

Presurgical sensorimotor mapping with functional MR imaging is gaining acceptance in clinical practice; however, to our knowledge, its therapeutic efficacy has not been assessed in a sizable group of patients. Our goal was to identify how preoperative sensorimotor functional studies were used to guide the treatment of neuro-oncologic and epilepsy surgery patients.

METHODS

We retrospectively reviewed the medical records of 46 patients who had undergone preoperative sensorimotor functional MR imaging to document how often and in what ways the imaging studies had influenced their management. Clinical management decisions were grouped into three categories: for assessing the feasibility of surgical resection, for surgical planning, and for selecting patients for invasive functional mapping procedures.

RESULTS

Functional MR imaging studies successfully identified the functional central sulcus ipsilateral to the abnormality in 32 of the 46 patients, and these 32 patients are the focus of this report. In epilepsy surgery candidates, the functional MR imaging results were used to determine in part the feasibility of a proposed surgical resection in 70% of patients, to aid in surgical planning in 43%, and to select patients for invasive surgical functional mapping in 52%. In tumor patients, the functional MR imaging results were used to determine in part the feasibility of surgical resection in 55%, to aid in surgical planning in 22%, and to select patients for invasive surgical functional mapping in 78%. Overall, functional MR imaging studies were used in one or more of the three clinical decision-making categories in 89% of tumor patients and 91% of epilepsy surgery patients.

CONCLUSION

Preoperative functional MR imaging is useful to clinicians at three key stages in the preoperative clinical management paradigm of a substantial percentage of patients who are being considered for resective tumor or epilepsy surgery.

Long-distance PCR-based screening for large rearrangements of the LDL receptor gene in Korean patients with familial hypercholesterolemia

BACKGROUND

The LDL receptor is a cell-surface protein that regulates plasma cholesterol by specific uptake of LDL particles from the blood circulation. Familial hypercholesterolemia (FH) results from defective catabolism of LDL, which is caused by mutations in the LDL-receptor gene.

METHODS

For the rapid and reliable detection of large rearrangements in the LDL-receptor gene, we established a screening method based on long-distance PCR as an alternative to Southern-blot hybridization. Using long-distance PCR, 45 unrelated Korean subjects heterozygous for FH were screened to assess the frequency and nature of major structural rearrangements in the LDL-receptor gene.

RESULTS

Two different deletion mutations, FH6 (same type as FH3 and FH311) and FH 32, were detected in four families by long-distance PCR. Detailed restriction mapping and sequence analysis showed that FH6 was a 5.71-kb deletion extending from intron 8 to intron 12 and that FH32 was a 2-kb deletion extending from intron 6 to intron 7. Sequence analysis for the breakpoints of all deletions detected in Korean FH patients showed that only the left arms of the Alu repetitive sequences were involved in the deletion event.

CONCLUSIONS

The screening method based on long-distance PCR provides a powerful strategy for the detection of large rearrangements in the LDL-receptor gene and is a rapid and reliable screening alternative to Southern-blot hybridization.

Prenatal diagnosis of a fetus with distal 10q trisomy

Distal 10q trisomy is a well-defined but rare syndrome. Most cases are diagnosed in infancy or in childhood and rarely include prenatal findings. We present a case of fetal distal 10q trisomy with abnormal prenatal sonographic findings. A 19-year-old primigravida was referred for genetic counselling at 18 gestational weeks because her husband had a familial history of congenital anomalies. Genetic amniocentesis was thus performed and showed fetal distal 10q trisomy (10q24.1-->qter), 46,XX,der(22)t(10;22)(q24.1;p11.2)pat, resulting from paternal t(10;22) reciprocal translocation. Level II ultrasonograms further demonstrated bilateral hydronephrosis, ventricular septal defect and facial dysmorphism ascertained by three-dimensional ultrasound. The pregnancy was terminated at 22 gestational weeks. Post-mortem autopsy confirmed the sonographic findings. We suggest that abnormal prenatal sonographic findings such as cardio-vascular, renal and facial malformations should alert cytogeneticists to search for subtle chromosomal abnormalities.

Rapid diagnosis of common aneuploidies by quantitative fluorescent polymerase chain reaction

The most frequent autosomal aneuploidies in newborns involve chromosomes 21, 18, and 13. The pre- and postnatal detection of chromosome abnormalities has been almost exclusively performed by cytogenetic analysis. In this paper, we assess the diagnostic value of fluorescent polymerase chain reaction (PCR) using polymorphic small tandem repeats (STR). PCR products are distinguished via both size and fluorescence intensity to confirm the trisomy by either triallelic signals with similar fluorescence intensities or diallelic pattern with double-dose response. Compared with the relatively time-consuming and laborious classic cytogenetic analysis, this technique is rapid, inexpensive, and sensitive for the detection of trisomies 21, 18 and 13, particularly when the numbers of cells obtained from the prenatal diagnosis is limited or where cell culture fails. With greater samples tested and more STR markers available, this method will become more reliable. This study investigates the detection of aneuploides involving chromosomes 21, 18, and 13 by comparing quantitative fluorescent PCR with karyotyping performed by conventional cytogenetics. The results obtained by the two techniques were concordant in all trisomy cases of this study.

Hypermethylation of the p16 gene in sporadic T3N0M0 stage colorectal cancers: association with DNA replication error and shorter survival

Hypermethylation in the promoter region of the p16 gene was suspected to be involved in the tumorigenesis of colorectal cancers, although its clinical and biological significance remains obscure. In this study, we collected 84 T3N0M0 stage primary colorectal cancers that were curatively resected. The clinicopathologic data were reviewed. p16 hypermethylation was determined by a methylation-specific polymerase chain reaction (PCR). p53 overexpression was detected by immunocytochemistry (ICC). The point mutations in the 12 and 13 codons of the K-ras gene were screened by restriction enzyme analysis. Loss of heterozygosity (LOH) of the DCC (Deleted in Colorectal cancer) gene was examined by PCR using primers of the DCC (18q21) microsatellite marker. The DNA replication error (RER) was examined using 7 microsatellite markers at distinct chromosomal loci. p16 hypermethylation, regarded as an indication of p16 inactivation, was evident in 24 (28.6%) of the tumors. No correlation was found between p16 hypermethylation and various clinicopathologic factors, includinig age, sex, tumor location, tumor size, growth pattern, tumor differentiation, mucin production, vascular and/or lymphatic invasion, lymphocyte infiltration of the tumor, and serum level of carcinoembryonic antigen. There was no association between p16 hypermethylation of K-ras gene mutation, p53 overexpression and LOH of the DCC gene. However, p16 hypermethylation was significantly associated with DNA RER (p = 0.01). Survival analysis revealed a significant survival disadvantage of p16-hypermethylated versus non-p16-hypermethylated tumors (p = 0.0001). These findings indicate that p16 hypermethylation plays a role in the carcinogenesis of a subset of colorectal cancers; and the presence of p16 hypermethylation predicts shorter survival in T3N0M0 stage colorectal cancers.

No association of alpha-2 macroglobulin gene five-nucleotide deletion with AD in Taiwan Chinese

The alpha-2 macroglobulin five-nucleotide deletion (A2M-2) allele frequency was not significantly higher in the AD group than the control group (0.062 versus 0.101, p > 0.1). The odds ratio for AD in individuals with the A2M-2 allele was 0.582 (95% CI, 0.25 to 1.40). These results do not support the association between A2M-2 and AD in the Chinese population, although the allele frequency of A2M-2 is lower than that found in the Caucasian population. Therefore, A2M-2 might not be a significant risk factor of AD among Taiwan Chinese.

Inhibiting sulfate-reducing bacteria in biofilms on steel with antimicrobial peptides generated in situ

In batch and continuous fermentations, the reduction in corrosion of SAE 1018 mild steel and 304 stainless steel caused by inhibition of the reference sulfate-reducing bacterium (SRB) Desulfovibrio vulgaris by a protective, antimicrobial-producing Bacillus brevis biofilm was investigated. The presence of D. vulgaris produced a thick black precipitate on mild steel and a higher corrosion rate in batch cultures than that seen in a mono-culture of non-antimicrobial-producing Pseudomonas fragi K upon the addition of SRB to the aerobic P. fragi K biofilm. In continuous reactors, the polarization resistance RP decreased for stainless stell and increased for mild steel upon the addition of SRB to a P. fragi K biofilm. Addition of either 200 micrograms/ml ampicillin, chloramphenicol, or ammonium molybdate to batch and continuous reactors after SRB had colonized the metal was ineffective in killing SRB, as inferred from the lack of change in both Rp and the impedance spectra. However, when ampicillin was added prior to SRB colonization, the growth of SRB was completely inhibited on stainless steel in continuous reactors. Prior addition of ampicillin was only able to delay the growth of SRB on mild steel in continuous reactors. External addition of the purified peptide antimicrobial agent gramicidin S prior to the addition of SRB also inhibited the growth of SRB on stainless steel in continuous reactors, and the SRB were also inhibited on stainless steel in both batch and continuous reactors by producing gramicidin S in situ in a protective biofilm when the gramicidin-S-overproducing strain Bacillus brevis 18 was used.

Loss of heterozygosity in (LewisxF344)F1 rat urinary bladder tumors induced with N-butyl-N-(4-hydroxybutyl)nitrosamine followed by dimethylarsinic acid or sodium L-ascorbate

Dimethylarsinic acid (DMA), a main metabolite of arsenicals which are carcinogenic in man, exerts tumor-promoting activity on rat urinary bladder carcinogenesis initiated with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN). Sodium L-ascorbate (Na-AsA) is also a strong tumor promoter in this animal model. In this study, we used (LewisxF344)F, rats to compare molecular alterations in urinary bladder tumors caused by BBN followed by DMA or Na-AsA. Male, 6-week-old rats were given 0.05% BBN in their drinking water for 4 weeks, and then the rats in group 1 were maintained with no further treatment for 40 weeks. The animals of groups 2 and 3 were administered 0.01% DMA in their drinking water (group 2) or 5% Na-AsA in the powder diet (group 3) after the BBN treatment. Group 4 rats were given 0.05% BBN continuously for 36 weeks. At weeks 12, 20, 36 and 44, subgroups of rats were killed. Histopathological examination revealed promoting activity for DMA and, to a greater extent, Na-AsA on urinary bladder carcinogenesis. Loss of heterozygosity (LOH), detected with the polymerase chain reaction using 36 microsatellite markers, was found to be present in 2 of 9 (22%) urinary bladder tumors after treatment with DMA and 3 of 22 (14%) induced by continuous administration with BBN. No LOH was, however, detected in urinary bladder tumors after treatment with Na-AsA. The results thus suggest that the mechanisms of action of these two promoters, DMA and Na-AsA, may differ in rat urinary bladder carcinogenesis.

A 45-kDa cAMP-dependent phosphoprotein which is related to the product of Mst57Dc in Drosophila melanogaster

In Drosophila, the catalytic subunit of cAMP-dependent protein kinase (PKA) is preferentially expressed in the brain and the male reproductive organs. Although the cAMP response element binding protein (CREB) is a major target of PKA in the brain, the target of PKA in the male reproductive organs has been unknown. In the present study, three cAMP-dependent phosphoproteins (referred to as pp45, pp20, and pp10) were detected in the lumen fluid of male accessory glands. They were tissue-specific secretory proteins that accumulated only after eclosion, and were transferred to females during mating as other secretory proteins of the accessory glands. Among them, the 45-kDa phosphoprotein was partially purified and characterized. The purified protein was phosphorylated in vitro by the catalytic subunit of PKA. The partial amino acid sequence of this 45-kDa phosphoprotein was identical to the predicted amino acid sequence of the Mst57Dc cDNA, which is a male accessory gland transcript.

Specific p53 gene mutations in urinary bladder epithelium after the Chernobyl accident

After the Chernobyl accident, the incidence of urinary bladder cancers in the Ukraine population increased gradually from 26.2 to 36.1 per 100,000 between 1986 and 1996. Urinary bladder epithelium biopsied from 45 male patients with benign prostatic hyperplasia living in radiocontaminated areas of Ukraine demonstrated frequent severe urothelial dysplasia, carcinoma in situ, and a single invasive transitional cell carcinoma, combined with irradiation cystitis in 42 cases (93%). No neoplastic changes (carcinoma in situ or transitional cell carcinoma) were found in 10 patients from clean areas (areas without radiocontamination). DNA was extracted from the altered urothelium of selected paraffin-embedded specimens that showed obviously abnormal histology (3 cases) or intense p53 immunoreactivity (15 cases), and mutational analysis of exons 5-8 of the p53 gene was performed by PCR-single-strand conformational polymorphism analysis followed by DNA sequencing. Nine of 17 patients (53%) had one or more mutations in the altered urothelium. Urine sediment samples were also collected from the patients at 4-27 months after biopsy and analyzed by PCR-single-strand conformational polymorphism analysis or yeast functional assay, and identical or additional p53 mutations were found in four of five cases. Interestingly, a relative hot spot at codon 245 was found in five of nine (56%) cases with mutations, and 11 of the 13 mutations determined (73%) were G:C to A:T transitions at CpG dinucleotides, reported to be relatively infrequent (approximately 18%) in human urinary bladder cancers. Therefore, the frequent and specific p53 mutations found in these male patients may alert us to a future elevated occurrence of urinary bladder cancers in the radiocontaminated areas.