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PubMed2001

Fingerprinting of cell lines by directed amplification of minisatellite-region DNA (DAMD).

The development of in vitro propagation of cells has been an extraordinary technical advance for several biological studies. The correct identification of the cell line used, however, is crucial, as a mistaken identity or the presence of another contaminating cell may lead to invalid and/or erroneous conclusions. We report here the application of a DNA fingerprinting procedure (directed amplification of minisatellite-region DNA), developed by Heath et al. [Nucleic Acids Research (1993) 21: 5782-5785], to the characterization of cell lines. Genomic DNA of cells in culture was extracted and amplified by PCR in the presence of VNTR core sequences, and the amplicons were separated by agarose gel electrophoresis. After image capture with a digital camera, the banding profiles obtained were analyzed using a software (AnaGel) specially developed for the storage and analysis of electrophoretic fingerprints. The fingerprints are useful for construction of a data base for identification of cell lines by comparison to reference profiles as well as comparison of similar lines from different sources and periodic follow-up of cells in culture.

Animals↗
PubMed2025

Real-world deployment of a fine-tuned pathology foundation model for lung cancer biomarker detection.

Artificial intelligence models using digital histopathology slides stained with hematoxylin and eosin offer promising, tissue-preserving diagnostic tools for patients with cancer. Despite their advantages, their clinical utility in real-world settings remains unproven. Assessing EGFR mutations in lung adenocarcinoma demands rapid, accurate and cost-effective tests that preserve tissue for genomic sequencing. PCR-based assays provide rapid results but with reduced accuracy compared with next-generation sequencing and require additional tissue. Computational biomarkers leveraging modern foundation models can address these limitations. Here we assembled a large international clinical dataset of digital lung adenocarcinoma slides (N = 8,461) to develop a computational EGFR biomarker. Our model fine-tunes an open-source foundation model, improving task-specific performance with out-of-center generalization and clinical-grade accuracy on primary and metastatic specimens (mean area under the curve: internal 0.847, external 0.870). To evaluate real-world clinical translation, we conducted a prospective silent trial of the biomarker on primary samples, achieving an area under the curve of 0.890. The artificial-intelligence-assisted workflow reduced the number of rapid molecular tests needed by up to 43% while maintaining the current clinical standard performance. Our retrospective and prospective analyses demonstrate the real-world clinical utility of a computational pathology biomarker.

Humans↗
PubMed1999

Hypertrophic osteoarthropathy can indicate recurrence of Whipple's disease.

We report the case of a patient with Whipple's disease (WD) who developed hypertrophic osteoarthropathy (HOA) characterized by digital clubbing, periostosis of the tubular bones, and polysynovitis. The HOA disclosed the recurrence of the patient's WD, since polymerase chain reaction (PCR) analysis clearly demonstrated the presence of Tropheryma whippelii in the synovial fluid from the patient's left knee. Initiation of appropriate antibiotic therapy resulted in complete healing of all clinical rheumatologic manifestations within 2 months and in disappearance of radiographic bone changes at 7-month followup. We suggest that HOA be included within the spectrum of rheumatologic manifestations of WD, and that an evaluation for WD should be considered in patients, especially middle-aged men, presenting with HOA even without gastrointestinal symptoms. PCR analysis may be useful in accurate diagnosis and management of early WD with unusual clinical manifestations, and may contribute to decreased morbidity and mortality.

Anti-Bacterial Agents↗
PubMed2003

Differential Ca2+ signaling by thrombin and protease-activated receptor-1-activating peptide in human brain microvascular endothelial cells.

Thrombin and related protease-activated receptors 1, 2, 3, and 4 (PAR1-4) play a multifunctional role in many types of cells including endothelial cells. Here, using RT-PCR and immunofluorescence staining, we showed for the first time that PAR1-4 are expressed on primary human brain microvascular endothelial cells (HBMEC). Digital fluorescence microscopy and fura 2 were used to monitor intracellular Ca2+ concentration ([Ca2+]i) changes in response to thrombin and PAR1-activating peptide (PAR1-AP) SFFLRN. Both thrombin and PAR1-AP induced a dose-dependent [Ca2+]i rise that was inhibited by pretreatment of HBMEC with the phospholipase C inhibitor U-73122 and the sarco(endo)plasmic reticulum Ca2+-ATPase inhibitor thapsigargin. Thrombin induced transient [Ca2+]i increase, whereas PAR1-AP exhibited sustained [Ca2+]i rise. The PAR1-AP-induced sustained [Ca2+]i rise was significantly reduced in the absence of extracellular calcium or in the presence of an inhibitor of store-operated calcium channels, SKF-96365. Restoration of extracellular Ca2+ to the cells that were initially activated by PAR1-AP in the absence of extracellular Ca2+ resulted in significant [Ca2+]i rise; however, this effect was not observed after thrombin stimulation. Pretreatment of the cells with a low thrombin concentration (0.1 nM) prevented [Ca2+]i rise in response to high thrombin concentration (10 nM), but pretreatment with PAR1-AP did not prevent subsequent [Ca2+]i rise to high PAR1-AP concentration. Additionally, treatment with thrombin decreased transendothelial electrical resistance in HBMEC, whereas PAR1-AP was without significant effect. These findings suggest that, in contrast to thrombin, stimulation of PAR1 by untethered peptide SFFLRN results in stimulation of store-operated Ca2+ influx without significantly affecting brain endothelial barrier functions.

Calcium↗
PubMed1998

A hemagglutinating variant of Prevotella melaninogenica isolated from the oral cavity.

Strains resembling Prevotella melaninogenica were isolated from healthy subjects and patients with periodontal disease and were identified using: a 5-test phenotypic screen; commercial identification kits; and a 16S rRNA-based polymerase chain reaction (PCR) method. Eleven clinical isolates closely resembling P. melaninogenica, and all from patients with periodontitis, were able to agglutinate erythrocytes. In the electron microscope, hemagglutinating isolates showed fimbria-like structures, that were not seen on non-hemagglutinating isolates. Some strains were further classified with PCR-restriction fragment-length polymorphism (RFLP) of 16S rRNA genes. Amplified 16S rDNA was digested using five different endonucleases, separated with agarose gel electrophoresis, stained and photographed. Photographs were then scanned, digitized and a distance matrix calculated using Dice coefficient, where the presence or absence of a band was used as a character. The distance matrix was plotted as a phenogram. At 70% similarity six clusters were seen. Type strains of separate Prevotella species did not fall into any cluster. Hemagglutinating isolates fell into three clusters: four clustered with the type strains of P. melaninogenica and Prevotella veroralis; four with other P. melaninogenica isolates and two hemagglutinating isolates clustered together Prevotella loescheii. The PCR-RFLP results showed that the hemagglutinating strains did not form a homogenous group inside the Prevotella genus.

Adult↗
PubMed1996

The relationship of human papillomavirus-related cervical tumors to cigarette smoking, oral contraceptive use, and prior herpes simplex virus type 2 infection.

It has now been established that infection with human papillomavirus (HPV) is necessary for the development of most cervical cancers. HPV is not sufficient for the development of cancer. Other exposures or host factors are necessary for cancer to occur. As part of an ongoing, population-based case-control study of invasive cervical cancer, we investigated the role of cigarette smoking, oral contraceptive (OC) use, and herpes simplex virus type 2 (HSV-2) as potential cofactors with HPV in the development of cervical cancer. Residents of three counties in western Washington State who were diagnosed with invasive squamous cell cervical cancer (n = 314) from January 1986 through December 1992 were interviewed about their sexual, reproductive, contraceptive, and cigarette smoking histories. Similar information was obtained from control women identified through random digit dialing (n = 672). The sera from 206 cases and 522 controls were tested for both HPV 16 capsid antibodies and HSV-2 antibodies. PCR was used to test paraffin-embedded tumor tissues for the presence of HPV DNA types 6, 16, 18, 31, 33, 35, and 39. Women with cervical cancer were more likely to be current smokers at diagnosis than population controls [relative risk (RR), 2.5; 95% confidence interval (CI), 1.8-3.4]. The risk associated with smoking was present to a similar extent among women positive and negative for HPV as measured by HPV 16 capsid antibodies and HPV DNA in the tumor tissue (cases). OC use was only important if first use was at an early age, particularly ages < or = 17 years (RR, 2.3; 95% CI, 1.4-3.8). There was only a slight risk for cervical cancer associated with antibodies to HSV-2 (RR, 1.2; 95% CI, 0.9-1.7). However, when we stratified by markers of HPV exposure, we found a significant increase in risk associated with HSV-2 among women negative for HPV 16 antibodies (RR, 2.0; 95% CI, 1.3-3.0), which was strengthened when we confined our analysis to cases whose tumors were HPV DNA negative (RR, 3.6; 95% CI, 1.6-8.0). There was no indication that cigarette smoking, OC use, or HSV-2 infection influence the ability of HPV infection to cause invasive cervical cancer. OC use may only be important in the etiology of invasive squamous cell cervical tumors if the use occurs at a critical time in the development of a woman's reproductive tract, at ages < or = 17 years. The majority of risk associated with HSV-2 was confined to HPV-negative tumors, indicating a possible separate pathway to disease that may account for 5-10% of invasive cervical cancers.

Adolescent↗
PubMed2005

Directed evolution of a ring-cleaving dioxygenase for polychlorinated biphenyl degradation.

DoxG, an extradiol dioxygenase involved in the aerobic catabolism of naphthalene, possesses a weak ability to cleave 3,4-dihydroxybiphenyls (3,4-DHB), critical polychlorinated biphenyl metabolites. A directed evolution strategy combining error-prone PCR, saturation mutagenesis, and DNA shuffling was used to improve the polychlorinated biphenyl-degrading potential of DoxG. Screening was facilitated through analysis of filtered, digital imaging of plated colonies. A simple scheme, which is readily adaptable to other activities, enabled the screening of >10(5) colonies/h. The best variant, designated DoxGSMA2, cleaved 3,4-DHB with an apparent specificity constant of 2.0 +/- 0.3 x 10(6) m(-1) s(-1), which is 770 times that of wild-type (WT) DoxG. The specificities of DoxGSMA2 for 1,2-DHN and 2,3-DHB were increased by 6.7-fold and reduced by 2-fold, respectively, compared with the WT enzyme. DoxGSMA2 contained three substituted residues with respect to the WT enzyme: L190M, S191W, and L242S. Structural data indicate that the side chains of residues 190 and 242 occur on opposite walls of the substrate binding pocket and may interact directly with the distal ring of 3,4-DHB or influence contacts between this substrate and other residues. Thus, the introduction of two bulkier residues on one side of the substrate binding pocket and a smaller residue on the other may reshape the binding pocket and alter the catalytically relevant interactions of 3,4-DHB with the enzyme and dioxygen. Kinetic analyses reveal that the substitutions are anti-cooperative.

Base Sequence↗
PubMed2003

Infection and inflammation in skeletal muscle from nonhuman primates infected with different genospecies of the Lyme disease spirochete Borrelia burgdorferi.

Lyme borreliosis is a multisystemic disease caused by various genospecies of the spirochete Borrelia burgdorferi. To investigate muscle involvement in the nonhuman primate (NHP) model of Lyme disease, 16 adult Macaca mulatta animals inoculated with strain N40 of B. burgdorferi sensu strictu by syringe or by tick bite or with strain Pbi of B. burgdorferi genospecies garinii by syringe were studied. Animals were necropsied while immunosuppressed on day 50 (two animals each inoculated with B. burgdorferi N40 by syringe and with B. garinii Pbi by syringe) or on day 90, 40 days after immunosuppression had been discontinued (four animals each inoculated with strain N40 by syringe, with strain N40 by tick bite, and with strain Pbi by syringe). Skeletal muscles removed at necropsy were studied by (i) microscopic examination of hematoxylin-eosin-stained sections for inflammation and tissue injury; (ii) immunohistochemical and digital image analyses for antibody and complement deposition and cellular inflammation; (iii) Western blot densitometry for the presence of antibodies; and (iv) reverse transcription-PCR for measurement of the spirochetal load or C1q (the first component of the complement cascade) synthesis. The results showed that N40 was more infectious for NHPs than Pbi. NHPs inoculated with N40 but not with Pbi developed myositis. The inflammation in skeletal muscle was more severe in NHPs inoculated with N40 by syringe than in those inoculated by tick bite. The predominant cells in the inflammatory infiltrate were T cells and plasma cells. The deposition of antibody and complement in inflamed muscles from N40-inoculated NHPs was significantly higher than that in Pbi-inoculated NHPs. The spirochetal load was very high in the two N40-inoculated NHPs examined while they were immunosuppressed but decreased to minimal levels in the NHPs when immunocompetence was restored. We conclude that myositis can be a prominent feature of Lyme borreliosis depending on the infecting organism and host immune status.

Animals↗
PubMed1995

A physical map of chromosome 20 established using fluorescence in situ hybridization and digital image analysis.

The physical locations of 46 cosmid clones and 21 P1 clones were determined along the chromosome 20 axis relative to the p terminus (FLpter) using fluorescence in situ hybridization (FISH) and digital image microscopy. The cosmid clones were selected from the chromosomally enriched library LA20NC01. Nine P1 clones were selected from a pooled DuPont genomic library using PCR with primer pairs selected to amplify genetically mapped sequence-tagged sites. This information was used to relate the physical map to the genetic map. Twelve P1 clones were selected from the same library using PCR primer pairs that amplified known genes. Two of these, E2F and BCLX, had not been mapped previously.

Base Sequence↗
PubMed2003

Interaction of TRPC2 and TRPC6 in erythropoietin modulation of calcium influx.

Erythropoietin (Epo) modulates calcium influx through voltage-independent calcium-permeable channel(s). Here, we characterized the expression of transient receptor potential channels (TRPCs) in primary erythroid cells and examined their regulation. Erythroblasts were isolated from the spleens of phenylhydrazine-treated mice, and Epo stimulation resulted in a significant and dose-dependent increase in [Ca](i). Among the classical TRPC channels, expression of three N-terminal splice variants of TRPC2 (clones 14, 17, and alpha) and of TRPC6 were demonstrated in these erythroblasts by both reverse transcriptase-PCR and Western blotting. Confocal microscopy confirmed localization to the plasma membrane. To determine the function of individual TRPC channels in erythropoietin modulation of calcium influx, digital video imaging was used to measure calcium influx through these TRPCs in a Chinese hamster ovary (CHO) cell model. Single CHO-S cells, expressing transfected Epo-R, were identified by detection of green fluorescent protein. Cells that express transfected TRPCs were identified by detection of blue fluorescent protein. [Ca](i) was monitored with Fura Red. Epo stimulation of CHO-S cells transfected with single TRPC2 isoforms (clone 14, 17, or alpha) and Epo-R resulted in a significant increase in [Ca](i). This was not observed in cells transfected with Epo-R and TRPC6. In addition, coexpression of TRPC6 with TRPC2 and Epo-R inhibited the increase in [Ca](i) observed after Epo stimulation. Immunoprecipitation experiments demonstrated that TRPC2 associates with TRPC6, indicating that these TRPCs can form multimeric channels. These data demonstrate that specific TRPCs are expressed in primary erythroid cells and that two of these channels, TRPC2 and TRPC6, can interact to modulate calcium influx stimulated by erythropoietin.

Alternative Splicing↗
PubMed2004

Five-locus HLA typing of hematopoietic stem cell donor volunteers using PCR sequence specific primers.

We have developed a strategy for five-locus human leukocyte antigen (HLA) typing of hematopoeitic stem cell (HSC) donors using the polymerase chain reaction with sequence-specific primers (PCR-SSP). The PCR-SSP method is robust, reproducible, and accurate. New PCR-SSP mixtures can be added as required and all reactions are carried out under the same conditions, which can easily be applied to the typing of other loci, e.g., ABO blood groups. Initially, 127 PCR-SSP reactions were used to detect simultaneously HLA-A, -B, -C, -DRB1/3/4/5, and DQB1 alleles, differentiated generally to the level of the first two digits of the allele name, essentially equivalent to the serological split specificity. Approximately 40% of subjects were tested against a further 29 HLA-A, -B SSP mixtures to exclude rare alleles and unambiguously assign a two-digit HLA allele family. This gave an overall typing resolution equivalent to or greater than the split specificity level and covered all HLA-A, -B, -C, -DRBland DQB1 alleles listed in the WHO's Nomenclature for Factors of the HLA System, 2000. The Welsh Bone Marrow Donor Registry has used this strategy to HLA type over 35,000 HSC donors over 9 years. Comprehensive and accurate five-locus HLA typing allows confident and rapid identification of potential matched HSC donors for patients requiring stem cell transplantation generally without the need for typing additional loci. This allows resources to be focused directly on allele level typing of DRB1 and other loci. This strategy decreases overall donor work-up time, which is a major benefit to patients.

Alleles↗
PubMed2003

Influence of interleukin-1 gene polymorphism on periodontal regeneration in intrabony defects.

The aim of this controlled retrospective study was to evaluate the influence of an IL-1 gene polymorphism on the clinical and radiographic healing outcomes of GTR therapy. The study included 47 adult periodontitis patients with 94 deep intrabony defects treated by GTR using different membrane materials. The following clinical parameters were recorded at baseline and 12 months after surgery: papillary bleeding index (PBI), gingival recession (REC), probing pocket depth (PPD), clinical attachment level (CAL), and the vertical relative attachment gain (V-rAG). Bone changes in the defect regions due to GTR therapy were quantitatively evaluated using digital subtraction radiography (DSR). Polymorphisms of the IL-1A gene at position - 889 and of the IL-1B gene at position + 3953 were analyzed by PCR. Statistical analysis was performed using the Mann-Whitney-U and the Wilcoxon-Signed-Rank tests (alpha = 0.05). The study comprised 19 IL-1 genotype positive (IL-1 +) patients and 28 IL-1 genotype negative (IL-1 -) patients. Twelve months after GTR therapy, both patient groups revealed statistically significant PPD reductions and CAL gain [median (25/75% percentiles)]: Delta PPD [IL-1 + : 4.0 (2.5/5.0) mm; IL-1-: 3.8 (3.0/4.9) mm], Delta CAL [IL-1 + : 3.5 (3.0/4.8) mm; IL-1 -: 3.0 (1, 2/4, 5) mm]. V-rAG amounted to 60.0 (47.7/78.6)% in IL-1 + patients and 53.1 (43.4/81.9)% in IL-1 - patients. Both patient groups showed significant bone density gain in 40% (IL-1 +) and 43.6% (IL-1 -) of the initial defect area due to GTR. Neither the clinical nor the radiographic healing parameters revealed any statistically significant differences in the GTR healing outcome between IL-1 + and IL-1 - patients. In conclusion, these 12-month findings indicate that the IL-1 gene polymorphism has no influence on the clinical and radiographic regeneration results following GTR therapy.

Adult↗
PubMed2005

Molecular cloning of MSRG-11 gene related to apoptosis of mouse spermatogenic cells.

Beginning with a new contig of the expressed sequence tags (Mm.63892) obtained by comparing testis libraries with other tissue and cell line libraries using the digital differential display program, we cloned a new gene which is related to the apoptosis of mouse spermatogenic cells using the Genscan program and polymerase chain reaction (PCR) technology. The sequence data have been submitted to the GenBank database under accession number AY747687. The full cDNA length is 1074 bp, and the gene with 7 exons and 6 introns is located in mouse chromosome 1 H5. The protein is recognized as a new member of calmodulin (CaM) binding protein family because the sequence contains three short calmodulin-binding motifs containing conserved Ile and Gln residues (IQ motif) and is considered to play a critical role in interactions of IQ motif-containing proteins with CaM proteins. The putative protein encoded by this gene has 192 amino acid residues with a theoretical molecular mass of 23.7 kDa and a calculated isoelectric point of 9.71. The sequence shares no significant homology with any known protein in databases. RT-PCR and Northern blot analyses revealed that 1.3 kb MSRG-11 transcript was strongly expressed in adult mouse testis but weakly expressed in the spleen and thymus. The MSRG-11 gene was expressed at various levels, faintly at two weeks postpartum and strongly from three weeks postpartum in adult testes. The green fluorescence produced by pEGFP-C2/MSRG-11 was detected in the cytoplasm of COS7 cells 24 h post-transfection. The pcDNA3.1(?-)/MSRG-11 plasmid was constructed and introduced into COS7 cells using Lipofectamine 2000 transfection reagent (Invitrogen, Carlsbad, USA). MSRG-11 can accelerate COS7 cell apoptosis, which suggests that this gene may play an important role in the development of mouse testes and is a candidate gene of testis-specific apoptosis. Based on these observations, it was considered that we cloned a new gene which probably accelerates spermatogenetic cell apoptosis in mouse.

Amino Acid Sequence↗
PubMed1994

[Leber's hereditary optic neuropathy with onset at the age of 54 years].

We report a 55-year-old Japanese man who had an onset of bilateral progressive blurring of vision at age 54 years. His younger sister had diminished visual acuity since 14 years of age. On neurologic examination, bilateral optic atrophy was present. He could only count the digit numbers at 40 cm-distance with his right eye, and the visual acuity of the left eye was 0.08. Otherwise, neurologic examination was unremarkable. The PCR analysis of mitochondrial DNA prepared from whole blood revealed a G to A mutation at the nucleotide 11,778; the so-called Wallace's mutation. He was diagnosed as Leber's hereditary optic neuropathy. It is rare to see a patient with LHON with the onset after 50 years of age.

Age Factors↗
PubMedDate not supplied

Cryosurgery plus adjuvant systemic alpha2-interferon for HPV-associated lesions.

OBJECTIVE: The authors report their experience in patients with adjuvant systemic 2-interferon with the aim of defining the effectiveness, side-effects, indications and limitations of this treatment. MATERIALS AND METHODS: From January 1989 to December 1996, 123 patients with genital, anorectal and perineal HPV lesions were treated with cryosurgery; adjuvant systemic a2-interferon was administered to 38 of them. There were 76 female and 47 male patients (median age of 29 years, range; 15-56 years). Clinical examinations included: digital rectal examination, head and neck examination, urethral meatus inspection and, in female patients, gynaecological examination; they underwent colposcopylurethroscopy, proctosigmoidoscopy, cystoscopy (in advanced disease); scraping for cytology and PCR analysis, and biopsy for histology. Twenty-three percent of patients had more than one site involved; upper digestive tract involvement was observed in 6.6% and 47% had lesions larger than 6 sqcm. Twenty-five females with genital lesions had esocervical lesions only; ten of them had SIL1, while seven a SIL3. RESULTS: Ninety-eight out of 123 patients (79.7%) were recurrence-free after a median follow-up of 32 months. A recurrence was observed in 25 patients: in univariate analysis, recurrence of disease occurred more frequently in females (p = 0.04), in patients with longer duration of symptoms (p = 0.0002),with wider lesions (p = 0.00015), with head and neck involvement (p < 0.01), and in HIV-positive patients (p = 0.03). In multivariate analysis, duration of symptoms (p = 0.005), head and neck involvement (p = 0.01), and width of lesion > 3 sq cm (p = 0.025) were associated with increased risk CONCLUSION: Our findings confirm the value of cryosurgery in the treatment HPV lesions; it is less traumatic, and gives good aesthetic and functional results; moreover, large lesions may be treated and the depth of cryonecrosis is more suitably adapted. Patients amenable to adjuvant treatment with a2-interferon should have multiorgan involvement, HPV type 16 or 18, lesions >3 sqcm, long lasting symptoms (>6 months) and presence of SIL.

Adolescent↗
PubMed1999

Performance characteristics of a Kodak computed radiography system.

The performance characteristics of a photostimulable phosphor based computed radiographic (CR) system were studied. The modulation transfer function (MTF), noise power spectra (NPS), and detective quantum efficiency (DQE) of the Kodak Digital Science computed radiography (CR) system (Eastman Kodak Co.-model 400) were measured and compared to previously published results of a Fuji based CR system (Philips Medical Systems-PCR model 7000). To maximize comparability, the same measurement techniques and analysis methods were used. The DQE at four exposure levels (30, 3, 0.3, 0.03 mR) and two plate types (standard and high resolution) were calculated from the NPS and MTF measurements. The NPS was determined from two-dimensional Fourier analysis of uniformly exposed plates. The presampling MTF was determined from the Fourier transform (FT) of the system's finely sampled line spread function (LSF) as produced by a narrow slit. A comparison of the slit type ("beveled edge" versus "straight edge") and its effect on the resulting MTF measurements was also performed. The results show that both systems are comparable in resolution performance. The noise power studies indicated a higher level of noise for the Kodak images (approximately 20% at the low exposure levels and 40%-70% at higher exposure levels). Within the clinically relevant exposure range (0.3-3 mR), the resulting DQE for the Kodak plates ranged between 20%-50% lower than for the corresponding Fuji plates. Measurements of the presampling MTF with the two slit types have shown that a correction factor can be applied to compensate for transmission through the relief edges.

Evaluation Studies as Topic↗
PubMed1989

[Thoracic diagnosis at the intensive care unit: digital radiography].

Only few reports have been published so far on the clinical use of digital luminescence radiography (DLR). We report on 3.000 x-ray examinations of the thorax in the intensive-care ward performed by us since a suitable system (Philips PCR) had been installed in December 1987. The following advantages must be pointed out in respect of using DLR in thoracic diagnosis in the intensive-care ward: No faulty exposures; the thorax can be x-rayed with the patient recumbent in bed, with lateral take: the image brightness in maintained at a constant level by histogram selection; electronic image processing and storage. Hence, DLR entails considerable improvement in x-ray diagnosis of intensive-care patients.

Humans↗
PubMed2002

Human papillomavirus and blastocyst apoptosis.

PURPOSE: The effect of human papillomavirus (HPV) DNA from the E6-E7 region on the integrity of DNA in blastocyst stage embryonic cells was studied. The study design paralleled the event whereby HPV DNA from the infecting virus would target host cell DNA. The objectives were (a) to determine if the DNA of blastocysts were disrupted by the presence of HPV DNA and (b) to determine if the intensity of DNA damage was associated with the type of HPV. METHODS: This study involved superovulating female mice, mating, collecting one-cell embryos, and culturing to the expanded blastocyst stage. The blastocysts were infected with PCR-synthesized DNA fragments from either HPV type 16, 18, 31, or 33. The blastocyst DNA were analyzed by comet assay after 24 h of incubation. The fluorescent images were digitized and the pixel intensity of each blastocyst was measured. RESULTS: Only the DNA of HPV type 16 was associated with significant DNA fragmentation in comparison with the other HPV types. There was no relationship between HPV DNA fragment size and the intensity of DNA fragmentation. CONCLUSIONS: The data suggested that one mode of action of HPV type 16 was to initiate apoptosis of embryonic cells through DNA fragmentation. The effect of HPV 16 occurred rapidly within 24 h. The intensity of DNA damage was not linked to the specific type of HPV. However, the results do not rule out the other HPV types affecting embryos under conditions different from this study.

Animals↗