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In eukaryotic cells, genes are interrupted by intervening sequences called introns. Introns are transcribed as part of a precursor RNA that is subsequently removed by splicing, giving rise to mature mRNA. However, introns are rarely found in bacteria. Actinobacillus actinomycetemcomitans is a periodontal pathogen implicated in aggressive forms of periodontal disease. This organism has been shown to produce cytolethal distending toxin (CDT), which causes sensitive eukaryotic cells to become irreversibly blocked at the [G.sub.2]/M phase of the cell cycle. In this study, we report the presence of introns within the cdt gene of A. actinomycetemcomitans. By use of reverse transcription-PCR, cdt transcripts of 2.123, 1.572, and 0.882 kb (RTA1, RTA2, and RTA3, respectively) were detected. In contrast, a single 2.123-kh amplicon was obtained by PCR with the genomic DNA. Similar results were obtained when a plasmid carrying cdt was cloned into Escherichia coli. Sequence analysis of RTA1, RTA2, and RTA3 revealed that RTA1 had undergone splicing, giving rise to RTA2 and RTA3. Two exon-intron boundaries, or splice sites, were identified at positions 863 to 868 and 1553 to 1858 of RTA1. Site-directed and deletion mutation studies of the splice site sequence indicated that sequence conservation was important in order for accurate splicing to occur. The catalytic region of the cdt RNA was located within the cdtC gene. This 0.56-kb RNA behaved independently as a catalytically active RNA molecule (a ribozyme) in vitro, capable of splicing heterologous RNA in both cis and trans configurations. more...

Protecting the mental health of healthcare workers is an urgent global public health priority. Healthcare workers, especially those immersed in palliative care, are prone to burnout due to the intense emotions associated with end-of-life caregiving. This study examines the efficacy of a novel, multimodal, and group-based Mindful-Compassion Art-based Therapy (MCAT) that integrates reflective self-awareness with creative emotional expression for protecting healthcare workers' mental health. A dual-arm open-label waitlist randomized controlled trial was conducted. A total of 56 healthcare workers were recruited from the largest homecare hospice in Singapore and randomized to the immediate-treatment condition of a standardized 6-week, 18-hours MCAT intervention (n =29), or the waitlist-control condition (n =27). Self-administered outcome measures on burnout, resilience, emotional regulation, self-compassion, death attitudes, and quality of life were collected at baseline, post-intervention/second-baseline at 6weeks, and follow-up/post-intervention at 12weeks. Results from mixed model ANOVAs reveal that treatment group participants experienced significant reduction in mental exhaustion, as well as significant improvements in overall emotional regulation, nonreactivity to intrusive thoughts, approach acceptance of death, and afterlife belief as compared to waitlist-control immediately after MCAT completion. Effect sizes of these impacts ranged from medium to large (η 2=0.65 to 0.170). Results from one-way ANOVAs further reveal that the treatment gains of reduced mental exhaustion and increased emotional regulation were maintained among treatment group participants at 12-weeks follow-up compared to baseline, with new benefits identified. These include increased ability to observe and describe one's experiences, elevated overall self-compassion, greater mindful awareness, enhanced common humanity, and better quality of life. Effect sizes of these impacts were large (η 2=0.128 to 0.298). These findings reflect the robust effectiveness and positive residual effects of MCAT for reducing burnout, building resilience, nurturing compassion, fostering collegial support, and promoting mental wellness among healthcare workers. The clinical model and applicability of MCAT in larger and more diverse caregiving contexts, such as family dementia care, are discussed. Clinical Trial Registration: ClinicalTrials.gov # NCT03440606, #NCT04548089. [ABSTRACT FROM AUTHOR] more...

Purpose: Prostate-specific membrane antigen (PSMA) PET/CT is increasingly used in patients with biochemical recurrence post prostatectomy to detect local recurrence and metastatic disease at low PSA levels. The aim of this study was to assess patterns of disease detection, predictive factors and safety using [18F]DCFPyL PET/CT versus diagnostic CT in patients being considered for salvage radiotherapy with biochemical recurrence post prostatectomy. Methods: We conducted a prospective trial recruiting 100 patients with detectable PSA post prostatectomy (PSA 0.2–2.0 ng/mL) and referred for salvage radiotherapy from August 2018 to July 2020. All patients underwent a PSMA PET/CT using the [18F]DCFPyL tracer and a diagnostic CT. The detection rates of [18F]DCFPyL PET/CT vs diagnostic CT were compared and patterns of disease are reported. Clinical patient and tumour characteristics were analysed for predictive utility. Thirty-day post-scan safety is reported. Results: Of 100 patients recruited, 98 were suitable for analysis with a median PSA of 0.32 ng/mL. [18F]DCFPyL PET/CT was positive 46.4% and equivocal 5.2%, compared to 15.5% positivity for diagnostic CT. Local recurrence was detected on [18F]DCFPyL PET/CT in 28.5%, nodal disease in 27.5% and bony metastases in 6.1% of patients. Both ISUP grade group (p < 0.001) and pre-scan PSA (p = 0.029) were significant predictors of [18F]DCFPyL PET/CT positivity, and logistic regression generated probabilities combining the two showed improved prediction rates. No significant safety events were reported post [18F]DCFPyL administration. Conclusions: [18F]DCFPyL PET/CT increases detection of disease in patients with biochemical recurrence post prostatectomy compared to diagnostic CT. Patients being considered for salvage radiotherapy with a PSA >0.2 ng/mL should be considered for [18F]DCFPyL PET/CT scan. Trial registration: Australian New Zealand Clinical Trials Registry Number: ACTRN12618001530213 (http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=375932&isReview=true) [ABSTRACT FROM AUTHOR] more...

Abstract Background Immunofluorescence and virus culture are the main methods used to diagnose acute respiratory virus infections. Diagnosing these infections using nucleic acid amplification presents technical challenges, one of which is facilitating the different optimal annealing temperatures needed for each virus. To overcome this problem we developed a diagnostic molecular strip which combined a generic nested touchdown protocol with in-house primer master-mixes that could recognise 12 common respiratory viruses. Results Over an 18 month period a total of 222 specimens were tested by both immunofluorescence and the molecular strip. The specimens came from 103 males (median age 3.5 y), 80 females (median age 9 y) and 5 quality assurance scheme specimens. Viruses were recovered from a number of specimen types including broncho-alveolar lavage, nasopharyngeal secretions, sputa, post-mortem lung tissue and combined throat and nasal swabs. Viral detection by IF was poor in sputa and respiratory swabs. A total of 99 viruses were detected in the study from 79 patients and 4 quality control specimens: 31 by immunofluorescence and 99 using the molecular strip. The strip consistently out-performed immunofluorescence with no loss of diagnostic specificity. Conclusions The touchdown protocol with pre-dispensed primer master-mixes was suitable for replacing virus culture for the diagnosis of respiratory viruses which were negative by immunofluorescence. Results by immunofluorescence were available after an average of 4–12 hours while molecular strip results were available within 24 hours, considerably faster than viral culture. The combined strip and touchdown protocol proved to be a convenient and reliable method of testing for multiple viruses in a routine setting. more...

Abstract Background The association of Chlamydia pneumoniae with atherosclerosis is controversial. We investigated the presence of C. pneumoniae and other Chlamydia spp. in atheromatous carotid artery tissue. Methods Forty elective carotid endarterectomy patients were recruited (27 males, mean age 65 and 13 females mean age 68), 4 had bilateral carotid endarterectomies (n= 44 endarterectomy specimens). Control specimens were taken from macroscopically normal carotid artery adjacent to the atheromatous lesions (internal controls), except in 8 cases where normal carotid arteries from post mortem (external controls) were used. Three case-control pairs were excluded when the HLA DRB gene failed to amplify from the DNA. Genus specific primers to the major outer membrane protein (MOMP) gene were used in a nested polymerase chain reaction (nPCR) in 41 atheromatous carotid specimens and paired controls. PCR inhibition was monitored by spiking with target C. trachomatis. Atheroma severity was graded histologically. Plasma samples were tested by microimmunofluorescence (MIF) for antibodies to C. pneumoniae, C. trachomatis and C. psittaci and the corresponding white cells were tested for Chlamydia spp. by nPCR. Results C. pneumoniae was not detected in any carotid specimen. Twenty-five of 38 (66%) plasma specimens were positive for C. pneumoniae IgG, 2/38 (5%) for C. trachomatis IgG and 1/38 (3%) for C. psittaci IgG. Conclusions We were unable to show an association between the presence of Chlamydia spp. and atheroma in carotid arteries in the presence of a high seroprevalence of C. pneumoniae antibodies in Northern Ireland. more...

Four processes, namely 'surface adsorption', 'lattice incorporation', 'lattice diffusion', and 'lattice ejection' were identified for variety of unique nanostructures to gain insight into the complex doping chemistry of colloidal nanocrystals. The findings from the study could be used as guidelines to program the reaction temperature to accomodate all elementary processes and obtained successfully doped nanocrystals. more...

Three types of B lymphocytic tumors arise in BALB/c mice after they receive intraperitoneal injections of pristane and Abelson virus. On the basis of their morphology and association with Abelson [...] more...

Cases of synchronous prostate and colorectal adenocarcinomas have been sporadically reported. There are case reports on patients with synchronous prostate and rectal cancers treated with external beam radiotherapy alone or combined with high-dose rate brachytherapy boost to the prostate. Here, we illustrate a patient with synchronous prostate and rectal cancers treated using the volumetric arc therapy ( VMAT) technique. The patient was treated with radical radiotherapy to 50.4 Gy in 28 fractions to the pelvis, incorporating the involved internal iliac node and the prostate. A boost of 24 Gy in 12 fractions was delivered to the prostate only, using VMAT. Treatment-related toxicities and follow-up prostate-specific antigen and carcinoembryonic antigen were collected for data analysis. At 12 months, the patient achieved complete response for both rectal and prostate cancers without significant treatment-related toxicities. [ABSTRACT FROM AUTHOR] more...

Alpha-methyacyl-CoA racemase (AMACR), a mitochondrial and peroxisomal enzyme essential in lipid metabolism, is overexpressed in prostate cancer. Two different AMACR transcripts (designated IA and IIA), each derived from five exons, have been reported. AMACR IA, the most abundant form, encodes a 382-amino acid protein (Mw 42 kDa, pI 6.07). AMACR IIA contains an alternative fifth exon that has extensive homology to the human fumarate hydratase (FH) and encodes a 288-amino acid protein (Mw 32 kDa, pI 9.6). Here we report additional variants of IA and IIA whereby the transcripts lack exon 3 and are designated as IB (Mw 22 kDa, pI 10.31) and IIB (Mw 31 kDa, pI 9.44). Due to a frameshift, the alternative fifth exon in the IIA transcript encodes a polypeptide that differs from FH. In contrast, the IIB transcript, generated as a result of the dual alternative splicing events, encodes a polypeptide homologous with a highly conserved region of FH. We also identified a shorter variant form of IIA (IIAs, Mw 28 kDa, pI 9.65), which lacks the 5′ half of the alternative fifth exon. The carboxy termini of all five gene products differ as a result of the alternative splicing events. In prostate tumor tissues that overexpressed AMACR, both the A and B forms were overexpressed, suggesting coregulation. Only the predominant AMACR IA has an acidic pI and contains the previously identified peroxisomal targeting signal (PTS1) peptide, while the other four variants are basic proteins that lack the peroxisomal targeting signal peptide. These observations have implications for the cellular localization and function of these AMACR variants. [Copyright &y& Elsevier] more...

Background: Immunofluorescence and virus culture are the main methods used to diagnose acute respiratory virus infections. Diagnosing these infections using nucleic acid amplification presents technical challenges, one of which is facilitating the different optimal annealing temperatures needed for each virus. To overcome this problem we developed a diagnostic molecular strip which combined a generic nested touchdown protocol with in-house primer master-mixes that could recognise 12 common respiratory viruses. Results: Over an 18 month period a total of 222 specimens were tested by both immunofluorescence and the molecular strip. The specimens came from 103 males (median age 3.5 y), 80 females (median age 9 y) and 5 quality assurance scheme specimens. Viruses were recovered from a number of specimen types including broncho-alveolar lavage, nasopharyngeal secretions, sputa, post-mortem lung tissue and combined throat and nasal swabs. Viral detection by IF was poor in sputa and respiratory swabs. A total of 99 viruses were detected in the study from 79 patients and 4 quality control specimens: 31 by immunofluorescence and 99 using the molecular strip. The strip consistently out-performed immunofluorescence with no loss of diagnostic specificity. Conclusions: The touchdown protocol with pre-dispensed primer master-mixes was suitable for replacing virus culture for the diagnosis of respiratory viruses which were negative by immunofluorescence. Results by immunofluorescence were available after an average of 4-12 hours while molecular strip results were available within 24 hours, considerably faster than viral culture. The combined strip and touchdown protocol proved to be a convenient and reliable method of testing for multiple viruses in a routine setting. [ABSTRACT FROM AUTHOR] more...

The cytolethal distending toxin (Cdt) of Actinobacillus actinomycetemcomitans, a periodontal pathogen, is a newly described cytotoxin with immunosuppressive properties, capable of causing cell cycle arrest of lymphocytes. The objectives of this study were to investigate the occurrence of A. actinomycetemcomitans with the cdt genotype in the subgingival plaque of periodontitis patients and to determine the association of this bacterial genotype with periodontal disease. A total of 146 subgingival plaque samples from periodontitis patients were assayed by the PCR method using oligonucleotide primers targeting the cdt operon of A. actinomycetemcomitans. Primers targeting the leukotoxin gene A (ltxA) of A. actinomycetemcomitans was used to determine the occurrence of the bacteria in the plaque samples at baseline. At baseline, A. actinomycetemcomitans was detected in 106 out of 146 (73%) diseased sites studied. Among the 106 diseased sites found to harbor A. actinomycetemcomitans, 13 sites were positive for the bacteria with the cdt genotype (12%). Out of the 13 positive sites, 10 sites were obtained from patients diagnosed with aggressive periodontitis (77%). Thus, A. actinomycetemcomitans with the cdt genetic subtype has low occurrence in the subgingival plaque of periodontitis patients. However, a strong association was observed between the presence of the bacteria and aggressive forros of periodontitis. Thus, the cytotoxic and immunosuppressive properties of A. actinomycetemcomitans Cdt may function to cripple the host immunity and contribute to the pathogenesis of aggressive periodontitis. [ABSTRACT FROM AUTHOR] more...

Bacteroides forsythus has been described as a periodontopathogen and its presence in the subgingival plaque can lead to periodontal disease. Recently, a cysteine protease designated as prtH was isolated and characterized from 8. forsythia ATCC 43037. The purpose of this study was to determine the prevalence and the association of the pull gene of B. forsythus with periodontal disease. A total of 160 subgingival plaque samples were assayed with the polymerase chain reaction method using oligonucleotide primers targeting the prtH and the 16S rDNA genes of B. forsythus. Primers targeting the 16S rDNA gene of B. forsythus were used to determine the occurrence of the bacteria in the subgingival plaque samples at baseline. At baseline, B. forsythus was detected in 78 out of 86 (91%) diseased sites and 33 out of 74(45%) healthy sites studied. Among the 86 diseased sites examined, 73 sites (85%) were colonized by the bacteria with the prtH genotype, in sites of the periodontally healthy, 7 out of 73 (10%) possessed B. forsythus with the prtH genotype. The results obtained suggested strong association of the prtH gene of B. forsythus with adult periodontitis. Although this bacterial species was detected from about half of the periodontally healthy samples, only a fraction of these subjects possess the bacteria strain with the prtH genetic subtype. We propose the use of the prtH gene as an alternative to the more widely used 16S rDNA gene of B. forsythus, for a more accurate determination of the prevalence of periodontal health and disease in epidemiological studies and clinical screening. [ABSTRACT FROM AUTHOR] more...

Background: The association of Chlamydia pneumoniae with atherosclerosis is controversial. We investigated the presence of C. pneumoniae and other Chlamydia spp. in atheromatous carotid artery tissue. Methods: Forty elective carotid endarterectomy patients were recruited (27 males, mean age 65 and 13 females mean age 68), 4 had bilateral carotid endarterectomies (n= 44 endarterectomy specimens). Control specimens were taken from macroscopically normal carotid artery adjacent to the atheromatous lesions (internal controls), except in 8 cases where normal carotid arteries from post mortem (external controls) were used. Three case-control pairs were excluded when the HLA DRB gene failed to amplify from the DNA. Genus specific primers to the major outer membrane protein (MOMP) gene were used in a nested polymerase chain reaction (nPCR) in 41 atheromatous carotid specimens and paired controls. PCR inhibition was monitored by spiking with target C. trachomatis. Atheroma severity was graded histologically. Plasma samples were tested by microimmunofluorescence (MIF) for antibodies to C. pneumoniae, C. trachomatis and C. psittaci and the corresponding white cells were tested for Chlamydia spp. by nPCR. Results: C. pneumoniae was not detected in any carotid specimen. Twenty-five of 38 (66%) plasma specimens were positive for C. pneumoniae IgG, 2/38 (5%) for C. trachomatis IgG and 1/38 (3%) for C. psittaci IgG. Conclusions: We were unable to show an association between the presence of Chlamydia spp. and atheroma in carotid arteries in the presence of a high seroprevalence of C. pneumoniae antibodies in Northern Ireland. [ABSTRACT FROM AUTHOR] more...

The objective of this study was to assess the effectiveness of a dentifrice with 2% dibasic sodium citrate in poloxamer 407 in decreasing dentinal hypersensitivity. The test toothpaste was compared with a control toothpaste containing 0.76% sodium monofluorophosphate in a 6-week double-blind clinical trial. A total of 75 hypersensitive teeth were examined in the test group, while 100 hypersensitive teeth were in the control group. Changes in hypersensitivity levels were monitored after 6 weeks, using thermal, chemical and mechanical stimuli. At the end of 6 weeks, the test dentifrice was not significantly more effective than the control in decreasing dentinal hypersensitivity. Of the stimuli used, cold was the most effective in eliciting a hypersensitive response, followed by chemical stimulation and air. Heat and toothbrushing caused the least discomfort. [ABSTRACT FROM AUTHOR] more...

A letter to the editor is presented about the clinical cases of New Delhi metallo-β-lactamase 1 in Northern Ireland.

The article focuses on the study conducted to determine the periodontal status and treatment needs of the industrialized elderly in Singapore. four homes that were admitting the elderly were randomly selected. An oral examination was carried out for each subject at their respective institutions. All teeth presented were examined by a single operator. Of the 670 elderly subjects selected only 633 were examined. The oral health status of the elderly was poor, with only 1.4% of individuals showing no bleeding on probing only. more...

Abstract: Although the introduction of automated blood culture systems has dramatically reduced laboratory personnel bench time, 48 to 72 h is still required for the identification of pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) and the accurate determination of antimicrobial sensitivities for prompt optimal patient therapy and infection control initiatives. The following 4 DNA blood culture extraction methods were compared: (a) organic, (b) differential centrifugation and lysis, (c) alkali wash/lysis, and (d) Qiagen lysis/filtration (QIAGEN, West Sussex, UK). The benzyl alcohol extraction method (a) was found to be the most optimal method having a reasonable extraction time of 1.8 h and 100% correlation with the “gold standard” laboratory culture. A “dual locus” real-time polymerase chain reaction (PCR) targeting the S. aureus-specific thermonuclease nuc gene and the staphylococcal methicillin resistance determinant mecA gene were used as a reliable indicator of the presence of MRSA. In conjunction with the DNA extraction method (a), detection time for MRSA/MSSA isolates from positive blood cultures was dramatically reduced from at least 24 to 48 h to approximately 3 h. [Copyright &y& Elsevier] more...

Prostate-specific membrane antigen (PSMA) tracers have increased sensitivity in the detection of prostate cancer, compared with conventional imaging. We assessed the management impact of t>18 F-DCFPyL PSMA PET/CT in patients with prostate-specific antigen (PSA) recurrence after radical prostatectomy (RP) and report early biochemical response in patients who underwent radiation treatment. Methods: One hundred patients were enrolled into a prospective study, with a prior RP for prostate cancer, a PSA of 0.2-2.0 ng/mL, and no prior treatment. All patients underwent diagnostic CT and PSMA PET/CT, and management intent was completed at 3 time points (original, post-CT, and post-PSMA) and compared. Patients who underwent radiotherapy with 6-mo PSA response data are presented. Results: Ninety-eight patients are reported, with a median PSA of 0.32 ng/mL (95% CI, 0.28-0.36), pT3a/b disease in 71.4%, and an International Society of Urological Pathology grade group of at least 3 in 59.2%. PSMA PET/CT detected disease in 46.9% of patients, compared with 15.5% using diagnostic CT (PSMA PET, 29.2% local recurrence and 29.6% pelvic nodal disease). A major change in management intent was higher after PSMA than after CT (12.5% vs. 3.2%, P = 0.010), as was a moderate change in intent (31.3% vs. 13.7%, P = 0.001). The most common change was an increase in the recommendation for elective pelvic radiation (from 15.6% to 33.3%), nodal boost (from 0% to 22.9%), and use of concurrent androgen deprivation therapy (ADT) (from 22.9% to 41.7%) from original to post-PSMA intent because of detection of nodal disease. Eighty-six patients underwent 18 F-DCFPyL-guided radiotherapy. Fifty-five of 86 patients either did not receive ADT or recovered after ADT, with an 18-mo PSA response from 0.32 to 0.02 ng/mL; 94.5% of patients had a PSA of no more than 0.20 ng/mL, and 74.5% had a PSA of no more than 0.03 ng/mL. Conclusion: 18 F-DCFPyL PET/CT has a significant impact on management intent in patients being considered for salvage radiotherapy after RP with PSA recurrence. Increased detection of disease, particularly in the pelvic lymph nodes, resulted in increased pelvic irradiation and concurrent ADT use. Early results in patients who are staged with 18 F-DCFPyL PET/CT show a favorable PSA response., (© 2022 by the Society of Nuclear Medicine and Molecular Imaging.) more...

Background: The apatite compounds used most commonly in craniofacial reconstruction are highly crystalline and biologically inert ceramics. Because their capacity to be replaced by native bone is limited, they have found little application in repair of the growing craniofacial skeleton. Carbonated calcium phosphate cements more closely resemble the mineral phase of bone, thereby offering enhanced bioresorption and osteoconductivity, but their fate in the immature and mature craniofacial skeleton has not been investigated., Methods: The authors hypothesized that the capacity for cell-mediated remodeling of carbonated calcium phosphate cements is based on (1) their crystallographic and compositional similarity to the mineral phase of bone and (2) the osteogenic capacity of the host. Four noncritical-sized calvarial defects were created in six 3-week-old and six 16-week-old Yorkshire pigs. The defects were repaired with autologous bone, sintered carbonated calcium phosphate cement disks with a higher crystal order, or carbonated calcium phosphate cement (Norian CRS; Synthes Maxillofacial, West Chester, Pa.). The fourth defect was left empty as a control. Specimens were harvested at 30 and 90 days postoperatively., Results: Empty defects healed with dense fibroconnective tissue in all groups. Autologous bone grafts underwent complete remodeling and replacement with woven bone at both time points. Sintered carbonated calcium phosphate disks demonstrated no bony ingrowth or remodeling. In immature animals, carbonated calcium phosphate cement implants were progressively replaced with woven bone through osteoclast-mediated resorption and osteoblast-mediated bone formation. Only minimal remodeling of the carbonated calcium phosphate cement implants was observed in skeletally mature animals., Conclusions: The results of these experiments suggest that the extent of remodeling of carbonated calcium phosphate cement is dependent on both the composition of the implant itself and the osteogenic capacity of the host and that carbonated calcium phosphate cement may be used successfully for inlay applications in the immature craniofacial skeleton. more...

When using gene expression profiling to understand human tumors, one is often confronted with long lists of genes that need to be further categorized into meaningful data. We performed a comprehensive evaluation and comparison of gene expression profiles obtained from pancreatic cancers to determine those genes most differentially expressed and thus with the most promise for translation into clinically useful targets. cDNA was prepared from 50 samples of normal pancreas or duodenal mucosal tissues, 7 samples of chronic pancreatitis, and 39 samples of pancreas cancer tissues or cancer cell lines and hybridized to the complete Affymetrix Human Genome U133 GeneChip set (arrays U133A and U133B) for simultaneous analysis of 45,000 fragments corresponding to 33,000 known genes and 6,000 expressed sequence tags. Genes expressed at levels at least 3-fold greater in the pancreatic cancers as compared with nonneoplastic tissues were identified. Three hundred seventy-seven Affymetrix fragments were identified as having > or = 3-fold expression levels in pancreas cancer specimens as compared with nonneoplastic tissues, corresponding to 234 known genes. Serial analysis of gene expression libraries (http://www.ncbi.nlm.nih.gov/SAGE/) of two normal pancreatic ductal cell cultures (HX and H126) were used to exclude 17 genes with high expression levels in the normal duct epithelium (more than five tags/library). Of the remaining 217 known genes, 75 have been previously reported as highly expressed in pancreatic cancers, while the remaining 142 genes are novel. We used principal components analysis (PCA) to identify the genes among these 217 identified as the most differentially expressed and specific to pancreatic cancer tissues or cell lines. Among the most differentially expressed genes identified by PCA were Mesothelin, Muc4, Muc5A/C, Kallikrein 10, Transglutaminase 2, Fascin, TMPRSS3 and stratifin. The differential expression identified by PCA for these genes indicates they are among the more attractive targets for novel therapeutic targets, tumor markers, or as a means of screening pancreatic cancer samples for information regarding tumor classification or potential therapeutic responses. Our findings were also compared in detail to the previously reported findings of highly expressed genes in other studies of global gene expression in pancreatic cancers. We found that robust changes in gene expression were most often identified by more than one gene expression platform. Forty genes were identified by more than one method (U133 oligonucleotide arrays, cDNA arrays or serial analysis of gene expression), and 6 of these genes were identified by all three methods. Our findings identify a novel set of genes as highly expressed in pancreatic cancer, validate the differential expression of previously reported genes, and provide additional support for those genes most differentially expressed to be translated into clinically useful targets. more...

Human alpha-methylacyl-CoA racemase (AMACR) was overexpressed in prostate cancer compared with nonmalignant tissues. The Gene Logic Inc. BioExpress database containing Affymetrix U133 GeneChip expression profiles of 4400 human normal, benign, diseased, and tumor samples from >60 tissue types was examined to determine the specificity of AMACR mRNA expression. One particular AMACR probeset was derived from an alternatively spliced exon with 88% identity to a 521-bp sequence that spans four exons of the fumarate hydratase. The predicted protein sequence revealed a novel GLGELIL peptide shared by both proteins. Whether the mitochondrial and peroxisomal AMACR described previously are distinct products from alternatively spliced transcripts remains to be determined. The determination of the cellular location and function of the altered AMACR will be critical in the elucidation of the role of AMACR in prostate cancer diagnosis and pathogenesis. more...

Calcium phosphate cements have been recently introduced for use in craniofacial reconstruction. In the clinical setting, however, pulsations of the underlying brain and dura may interfere with the crystallization of these cements, thereby rendering their use in cranioplasty problematic. To circumvent such problems, many clinicians have interposed synthetic resorbable plates or mesh between the dura and the cement. At the present time, however, little is known about the influence of such materials or their breakdown products on the fate of calcium phosphate cements. The specific aim of this project was to evaluate the biocompatibility, osteoconductivity, and remodeling capacity of a calcium phosphate cement after implantation into experimental calvarial defects when combined with a resorbable mesh underlay. Four 10-mm diameter full-thickness calvarial defects (two frontal, two parietal) were created in each of six 3-week-old Yorkshire pigs. The defects were treated as follows: 1) empty control, 2) macroporous polylactic acid (70/30 L/DL polylactic acid [PLA]) mesh, 3) Norian CRS calcium phosphate cement, and 4) Norian CRS over PLA mesh underlay. Animals were divided into two groups. Half of the animals were killed 30 days after surgery, and half were killed 180 days after surgery, and the graft recipient sites were examined histologically. At 30 days, minimal bone ingrowth was observed in untreated calvarial defects or in those that were treated with PLA plates alone. Defects treated with the cement alone demonstrated a modest amount of new woven bone deposition, primarily at the periphery of the implants. Defects treated with calcium phosphate cement over PLA mesh underlays were characterized by remodeling and woven bone deposition at 30 days, with complete or near-complete osseous bridging of the ectocranial implant surfaces. Progressive bone ingrowth was noted in all defects at 180 days, with near-complete replacement of all Norian CRS implants by host bone. The PLA mesh remained incompletely resorbed at 180 days. No inflammatory response to the implants was observed at either time point. Calcium phosphate cement may be safely used for craniofacial reconstruction in the presence of PLA implants without compromise to its biocompatibility, osteoconductivity, or remodeling capacity. more...

The potential for growth restriction has limited the use of alloplastic materials for reconstruction of the growing craniofacial skeleton. A calcium phosphate cement that has been introduced recently for craniofacial reconstruction crystallizes in situ into a substance that resembles more closely the mineral phase of bone, thereby offering the potential for enhanced bioresorption and osteoconductivity. The purpose of these experiments was to assess quantitatively craniofacial growth after reconstruction of frontal craniectomy defects in skeletally immature animals with this calcium phosphate bone mineral substitute. To simulate the calvarial defects that result from unilateral fronto-orbital advancement procedures, unilateral frontal bone flaps were removed in 3-week-old female Yorkshire piglets. The bone flaps were trimmed medially and posteriorly, and were then reattached to the supraorbital ridge. The resulting 5-mm gap between the frontal bone flap and the native bone was either filled with Norian CRS bone cement (N = 3) or left empty (N = 3). After 90 days, the animals were killed and the skulls were harvested and cleared. Direct craniometric measurements were performed on the prepared dry skulls to assess craniofacial growth in all dimensions. Extensive remodeling was observed within defects treated with the calcium phosphate cement, with complete or near-complete replacement of the cement by host bone, resulting in a solid bony union. Direct craniometric measurements revealed no differences in craniofacial growth in any dimension between the operated and unoperated sides of the cranium in either group. These studies demonstrate that craniofacial growth is not restricted after reconstruction of frontal craniectomy defects with carbonated calcium phosphate cement in skeletally immature animals. The remodeling capacity of this material offers promise for its safe use in reconstruction of the growing calvarium. more...