Simultaneous detection of Neisseria gonorrhoeae and Chlamydia trachomatis by PCR in genitourinary specimens from men and women attending an STD clinic

Neisseria gonorrhoeae and Chlamydia trachomatis are the two most common bacterial sexually transmitted infections that manifest primarily as urethritis in males and endocervicitis in females, though the infection may be asymptomatic especially in women. Since complications may occur in untreated symptomatic and asymptomatic infected individuals, early diagnosis and treatment of infected individuals is required to prevent severe sequelae and spread of these diseases. Recently molecular amplification assays like Polymerase Chain Reaction (PCR) and Ligase Chain Reaction (LCR) have been found to be highly sensitive and specific methods for detection of N. gonorrhoeae and C. trachonmatis not only in urethral and cervical specimens but also in urine. The objective of this study was to screen male and female Sexually Transmitted Disease (STD) clinic attenders, with and without symptoms suggestive of urethritis and cervicitis for presence of N. gonorrhoeae and C. trachomatis using a multiplex PCR based assay, to compare its performance with culture for N. gonorrhoeae and Direct Fluorescent Antibody (DFA) staining for C. trachomatis and also to compare the efficacy of PCR test performed on urine and genital swab specimens collected from this high risk group. Genital specimens and urine was collected from STD clinic attenders. N. gonorrhoeae and C. trachomatis was detected in genital specimens by culture and DFA respectively. Multiplex PCR was used to detect N. gonorrhoeae and C. trachomatis infection in both genital and urine specimens. Among men with urethritis, N. gonorrhoeae was detected in 70% by culture and 77% by PCR, while C. trachomatis as detected in 7.5% by DFA and 17.5% by PCR. Among females with endocervicitis, N. gonorrhoeae was detected in 7.7% by culture and 30.7% by PCR, while C. trachomatis was detected in 7.7% by DFA and in 15.4% by PCR. None of the asymptomatic males were positive for N. gonorrhoeae and C. trachomatis by conventional methods, while 43.9% were positive for N. gonorrhoeae and 7.5% for C. trachomatis by PCR. Fifty per cent of asymptomatic women were positive for C. trachomatis by PCR alone. We encountered PCR positive but culture/DFA negative results and also PCR negative but culture/DFA positive results. In view of this a single PCR test cannot be used for diagnosis and treatment of N. gonorrhoeae and C. trachomatis infection unless confirmed by a second test.

A "field change" of inhibited apoptosis occurs in colorectal mucosa adjacent to colorectal adenocarcinoma

BACKGROUND

Colorectal cancer is associated with a "field change" of increased proliferation throughout the colonic and rectal mucosa. Both proliferation and apoptosis are disrupted during carcinogenesis. Whether altered apoptosis contributes to this field change of microscopic abnormality is, however, unclear. Bcl-xL is an anti-apoptotic protein that inhibits apoptosis by preventing release of cytochrome c, a recognised pathway to cell death.

AIM

To determine whether Bcl-xL inhibition of apoptosis is increased in colorectal mucosa adjacent to colorectal adenocarcinoma over that in normal non-neoplastic colorectal mucosa.

PATIENTS

PATIENTS undergoing surgical resection for neoplastic (adenocarcinoma) or non-neoplastic disease of the colorectum (rectal prolapse, diverticular disease or volvulus).

METHODS

Formalin-fixed, paraffin-wax-embedded surgical colorectal resection specimens were immunostained for Bcl-xL protein. Labelling indices were determined by counting the proportion of positively stained cells in mucosal crypts.

RESULTS

85 patients were studied. Bcl-xL immunostaining was most marked in the upper third of mucosal crypts. It occurred in a minority of samples from non-neoplastic colorectal mucosa, but was seen in most mucosal samples adjacent to colorectal adenocarcinoma. Significant increases (p<0.001) were observed in Bcl-xL labelling indices in the mucosa at 1 cm (n = 46, median labelling index 31.8%, interquartile range 8.3-43.9%) and at 10 cm (n = 52, median labelling index 22.0%, interquartile range 0.0-36.3%) from colorectal carcinoma, compared with normal, non-neoplastic colorectal mucosa (n = 22, median labelling index 0.0%, interquartile range 0.0-0.0%).

CONCLUSIONS

The findings are consistent with a field change of inhibited apoptosis in mucosa adjacent to colorectal carcinoma.

Displacement imprinted polymer receptor analysis (DIPRA) for chlorophenolic contaminants in drinking water and packaging materials

The preparation of a molecularly imprinted polymer (MIP) for pentachlorophenol is described together with two alternative reporter derivatives for use in a displacement imprinted polymer receptor analysis (DIPRA) format procedure. In this procedure, alternative reporter molecules were rebound to the synthetic receptor sites and their displacement by the target analyte was employed as the basis of a simple procedure for the measurement of chlorophenols in water and packaging material samples. Water samples were extracted using the standard procedure (EPA 528) and a detection limit of 0.5 microg l(-1) was achieved using the DIPRA detection method, with good agreement between the displacement technique and GC-ECD analysis. A variety of packaging materials, extracted using a buffered detergent solution were also analysed using the DIPRA procedure and showed good agreement with GC results. In addition, investigation of the cross-reactivity of a range of pesticides and materials commonly encountered in environmental analysis indicated the procedure gave good discrimination between pesticides bearing a chlorophenolic moiety and other materials. The procedure is considered highly suitable for use as a rapid field-test method or for incorporation into a test kit device.

Development of an improved analytical method for the determination of carcinogenic polycyclic aromatic hydrocarbons in transformer oil

Polynuclear aromatic hydrocarbons (PAHs) are natural constituents of transformer oils and are essential in prolonging transformer in-service lifetime. Issues concerning PAH carcinogenicity demand methods that provide qualitative and quantitative information on the PAH composition of new and in-service oils to allow informed operational decisions to be made. However, current analytical methods focus on PAH fingerprinting, as opposed to quantitative analysis and are also cumbersome, relying on the use of large (>100 ml) volumes of organic solvents, some of which are hazardous. This paper reports a method for the improved quantification of carcinogenic PAHs in transformer oils that is both simple and repeatable. The method uses commercially available solid-phase extraction columns and millilitre volumes of relatively non-hazardous solvents. Extraction efficiencies of > or =74% were obtained for the Environmental Protection Agency priority PAHs. The method has potential for automation and high-throughput analysis and thus is of interest to industries that use transformer oils.

Altered cerebellar functional connectivity mediates potential adaptive plasticity in patients with multiple sclerosis

BACKGROUND

The cerebellum is of potential interest for understanding adaptive responses in motor control in patients with multiple sclerosis because of the high intrinsic synaptic plasticity of this brain region.

OBJECTIVE

To assess the relative roles of interactions between the neocortex and the cerebellum using measures of functional connectivity.

METHODS

A role for altered neocortical-cerebellar functional connectivity in adaptive responses to injury from multiple sclerosis was tested using 1.5 T functional magnetic resonance imaging (fMRI) during figure writing with the dominant right hand in patients with predominantly early relapsing-remitting multiple sclerosis.

RESULTS

Patients (n = 14) showed a more bihemispheric pattern of activation in motor cortex than healthy controls (n = 11). Correlations between task related signal changes in neocortical and cerebellar regions of interest were used as a measure of functional connectivity. Healthy controls showed strong functional connectivity between the left motor cortex and the right cerebellar dentate nucleus. Significant connectivity between the left primary motor cortex and the right dentate was not found in patients. However, patients had significant connectivity between the left premotor neocortex and the ipsilateral (left) cerebellar cortex (crus I), which was not found in healthy controls.

CONCLUSIONS

Changes in apparent cerebellar-neocortical functional connectivity may mediate potentially adaptive changes in brain motor control in patients with multiple sclerosis. Similar changes in the cerebellum and premotor cortex have been reported in the healthy brain during motor learning, suggesting that common mechanisms may contribute to normal motor learning and motor recovery after injury from multiple sclerosis.

Quantification of polynuclear aromatic hydrocarbons in transformer oils by enzyme immunoassay

Many polynuclear aromatic hydrocarbons (PAHs) are either known or suspected carcinogens and are a common constituent of mineral oils. Due to the large number of possible PAH structures, standard quantification methods fail since they either lack specificity or are too complex, requiring individual fractionation, identification, and quantification. A rapid, low-cost, novel analytical screening method, incorporating a silica-based solid-phase extraction (SPE) method linked to co-solvent dilution and quantification of total and carcinogenic PAH levels by immunoassay, is reported here. The method yielded high extraction efficiencies and minimal matrix effects. This novel approach yielded total and carcinogenic PAH levels x 5.7 and x 126, respectively, lower than that recorded by the industry-recognised BS2000 Pt. 346 (IP346) method which estimates the polyaromatic carbon (PAC) content of oils by gravimetry. The method is expected to be of benefit where an indication of PAH levels in oils is important for purchasing, management or disposal purposes and also for risk assessment and for appropriate labelling of oils in line with current legislation.

State-of-the-art imaging of pancreatic neoplasms

Pancreatic imaging with multidetector CT allows multiphase acquisition of thin slices in a single breath-hold and is especially valuable in obtaining isotropic three-dimensional reformations that improves our ability to provide accurate pre-operative vascular mapping. Advanced MR technology allows faster imaging of pancreas, thus facilitating MR cholangiopancreatography. Use of tissue-specific MR contrast agents, endoscopic ultrasound and PET in pancreatic imaging has evolved considerably. This review article discusses the role of CT, MR, endoscopic ultrasound and PET imaging in pancreas.

Role of anaerobes in acute pelvic inflammatory disease

Pouch of Douglas aspirates were collected from 50 women with history and examination suggestive of acute pelvic inflammatory disease (PID) and 20 healthy women admitted for tubal ligation served as control. A total of 57 microorganisms were isolated from 37 patients out of 50 in study group. Of 37 positive cultures 21(56.7%) were monomicrobial and 16(43.2%) were polymicrobial. Most common symptom in study group was lower abdominal pain (90%), vaginal discharge (70%) and irregular bleeding (40%) and 30% patients had history of intrauterine contraceptive device (IUCD) implantation. The predominant aerobic isolates were Escherichia coli, Coagulase Negative Staphylococcus (CONS), Staphylococcus aureus, Klebsiella pneumoniae while common anaerobes were Bacteroides fragilis, Prevotella melaninogenica, Fusobacterium nucleatum and Peptostreptococcus spp. Our study shows that cefotaxime, cefuroxime and gentamicin may be used for gram negative aerobic bacilli; cloxacillin, cephaloridine and erythromycin for aerobic gram positive cocci and amikacin and ceftazidime for Pseudomonas aeruginosa. Thus for optimum therapy of acute PID it is beneficial to keep in mind major conceptual changes and therapeutic realities that have influenced current understanding of acute PID and have affected the choice of therapy.

Intraductal papillary mucinous tumors of the pancreas

Intraductal papillary mucinous tumor (IPMT) is an uncommon pancreatic neoplasm with characteristic histology and distinctive clinicobiologic behavior. It is characterized by proliferation of ductal epithelium associated with ductal dilatation and variable mucin production. Due to indolent nature of these tumors, IPMTs are frequently missed or misdiagnosed. Prompt recognition and differentiation from other tumors are essential because IPMT has a better prognosis than other pancreatic malignancies. The purpose of this article is to display the radiologic spectrum of IPMT.

Microbial flora in orodental infections

The present study was carried out to compare the normal aerobic and anaerobic bacterial oral flora with flora from deep seated dental caries, gingivitis and adult periodontitis. All the samples belonging to both the control and study groups yielded microbes. Aerobe / Anaerobe ratio was high in normal flora (1.48) as compared to dental caries (0.9), gingivitis (0.72) and periodontitis (0.56). Ninety seven percent of orodental infections were polymicrobial and three or more microbes were found in 84% cases of study group as compared to 28% in controls. Streptococcus mutans and anaerobic lactobacilli were common in dental caries, Actinomyces and Peptostreptococcus spp. in gingivitis, Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in periodontitis.

Pelvic connective tissue resilience decreases with vaginal delivery, menopause and uterine prolapse

BACKGROUND

The late onset of pelvic visceral prolapse and incontinence after childbirth injury could be explained by menopause-associated connective tissue weakening. Uterosacral ligament resilience (UsR) was assessed to determine whether it influenced uterine or pelvic floor mobility, or varied with age, vaginal delivery, menopause or histological variations in the ligament.

METHODS

UsR was measured by tensiometry in ligaments from 85 hysterectomy specimens, and was correlated with the presence of symptomatic uterocervical prolapse, prehysterectomy uterine and anorectal mobility, patient age, history of vaginal delivery and menopause. Forty-five of these ligaments were examined for ligament thickness, muscle to collagen ratio, and oestrogen and progesterone receptor density. The results were correlated with UsR.

RESULTS

UsR was significantly reduced (P = 0.02) in symptomatic uterovaginal prolapse, but there was no correlation with either uterocervical or anorectal descent in women without symptomatic prolapse. There was a significant decrease in UsR with vaginal delivery (P = 0.003), menopause (P = 0.009) and older age (P = 0.005). The uterosacral ligament was significantly thinner and contained fewer oestrogen and progesterone receptors after menopause, but this did not affect UsR.

CONCLUSION

Where pelvic floor muscles are weakened, decreases in pelvic connective tissue resilience related to the menopause may facilitate progression to symptomatic pelvic visceral prolapse.

Tumour size measurement in an oncology clinical trial: comparison between off-site and on-site measurements

AIM

To evaluate the degree of variability between lesion measurements obtained by a single observer compared with multiple observers, and in selected cases evaluate which of the two measurements more accurately represented the lesion size.

MATERIALS AND METHODS

In this study we compared the performance of a single off-site observer to multiple on-site observers during measurement of 300 abdominal and thoracic lesions. Lesion measurements that were larger than 1cm(2), differed by more than 50%, but by less than 100%, were compared by a single adjudicator, who was blinded to the measurement source (n=46).

RESULTS

Measurements of the 300 lesions differed by an average of 109% (SD 251%). Of 266 lesions larger than 1cm(2), results of the single observer compared with multiple observers differed by more than 10% for 249 lesions, more than 30% for 169 lesions, more than 50% for 126 lesions, and more than 100% for 66 lesions. Forty-six lesions were compared by the adjudicator. The adjudicator selected the measurement of the single observer for 37 lesions (80.4%), and the measurement determined by one of the multiple observers for nine lesions (19.6%; p=0.00002).

CONCLUSION

Measurement of lesion size by a single observer compared with multiple observers reveals a high degree of variability. An adjudicator selected the measurement of the single observer more frequently than that of multiple observers, with statistical significance. These findings suggest that studies designed to quantify imaging features should limit the number of observers.

Antibiotic susceptibility of bacterial isolates in gingivitis and periodontitis

The present study was conducted to isolate aerobic as well as anaerobic microbes from patients of gingivitis and adult periodontitis and to study the susceptibility patterns of these isolates to different antibiotics. In our study all the samples belonging to the control as well as the study groups yielded microbes. Aerobes and facultative anaerobes were isolated from 100 percent and 96 percent cases of normal gingiva and orodental infections respectively. Anaerobes were isolated from 80 percent of the normal gingival samples and 97 percent of the cases of orodental infections. Metronidazole was found to be the best for the anaerobes while the aerobes and facultative anaerobes showed good susceptibility to cefazolin and cefotaxime.

Evaluation of germ tube test in various media

One of the most valuable tests for the rapid presumptive identification of Candida albicans is germ tube production. Previously researchers have concluded superior results with serum in germ tube test. However, handling of pooled human serum has danger of acquisition of hepatitis and HIV infections. Therefore, in the present study we compared various media--pooled human serum, sterile horse serum, peptone water and tryptic soy broth. It was observed that human serum remains to be the best with 100% positivity for identification of C. albicans followed by horse serum (76.3%), peptone water (61.8%) and tryptic soy broth (61.8%).

Thorotrast-induced cholangiocarcinoma: case report

Thorotrast, a contrast medium used extensively before being banned in 1950s, delivers a densely ionizing, high linear energy transfer type of radiation that predisposes to malignancies. We report a case of peripheral cholangiocarcinoma and describe its computed tomographic and magnetic resonance imaging features in a patient who developed it 48 years after exposure to Thorotrast.

Effect of manipulation of primary tumour vascularity on metastasis in an adenocarcinoma model

One explanation for the clinical association between tumour vascularity and probability of metastasis is that increased primary tumour vascularity enhances haematogenous dissemination by offering greater opportunity for tumour cell invasion into the circulation (intravasation). We devised an experimental tumour metastasis model that allowed manipulation of primary tumour vascularity with differential exposure of the primary and metastatic tumour site to angiogenic agents. We used this model to assess the effects of local and systemic increases in the level of the angiogenic agent basic fibroblast growth factor on metastasis. BDIX rats with implanted hind limb K12/TR adenocarcinoma tumours received either intratumoural or systemic, basic fibroblast growth factor or saline infusion. Both intratumoural and systemic basic fibroblast growth factor infusion resulted in significant increases in tumour vascularity, blood flow and growth, but not lung metastasis, compared with saline-infused controls. Raised basic fibroblast growth factor levels and increase in primary tumour vascularity did not increase metastasis. The clinical association between tumour vascularity and metastasis is most likely to arise from a metastatic tumour genotype that links increased tumour vascularity with greater metastatic potential.

Chromodomain protein Swi6-mediated role of DNA polymerase alpha in establishment of silencing in fission Yeast

Although DNA replication has been thought to play an important role in the silencing of mating type loci in Saccharomyces cerevisiae, recent studies indicate that silencing can be decoupled from replication. In Schizosaccharomyces pombe, mating type silencing is brought about by the trans-acting proteins, namely Swi6, Clr1-Clr4, and Rhp6, in cooperation with the cis-acting silencers. The latter contain an autonomous replication sequence, suggesting that DNA replication may be critical for silencing in S. pombe. To investigate the connection between DNA replication and silencing in S. pombe, we analyzed several temperature-sensitive mutants of DNA polymerase alpha. We find that one such mutant, swi7H4, exhibits silencing defects at mat, centromere, and telomere loci. This effect is independent of the checkpoint and replication defects of the mutant. Interestingly, the extent of the silencing defect in the swi7H4 mutant at the silent mat2 locus is further enhanced in absence of the cis-acting, centromere-proximal silencer. The chromodomain protein Swi6, which is required for silencing and is localized to mat and other heterochromatin loci, interacts with DNA polymerase alpha in vivo and in vitro in wild type cells. However, it does not interact with the mutant pol alpha and is delocalized away from the silent mat loci in the mutant. Our results demonstrate a role of DNA polymerase alpha in the establishment of silencing. We propose a recruitment model for the coupling of DNA replication with the establishment of silencing by the chromodomain protein Swi6, which may be applicable to higher eukaryotes.

Comprehensive evaluation of patients with haematuria on multi-slice computed tomography scanner: protocol design and preliminary observations

An imaging protocol with a multi-slice CT scanner that allows comprehensive assessment of patients with haematuria is described. This protocol allows evaluation of the kidneys, ureters and bladder in a single examination using CT. This approach should streamline the diagnostic work-up of patients with haematuria.

Clinical applications of magnetic resonance cholangiopancreatography

Magnetic resonance cholangiopancreatography (MRCP) is a novel imaging technique used for noninvasive work-up of patients with pancreaticobiliary disease. Magnetic resonance cholangiopancreatography is useful in the evaluation of a host of pancreaticobiliary disorders, such as congenital disorders, calculus disease, biliary strictures, sclerosing cholangitis, chronic pancreatitis, and cystic pancreatic lesions. It not only provides useful preoperative information to surgeons and gastroenterologists but also serves as a valuable tool in the assessment of postoperative pancreaticobiliary ductal anatomy. Recent refinement of techniques allows faster imaging with superior image resolution. This review summarizes the role of MRCP in clinical practice.

Sniffing out disease using the artificial nose

Is there information in the odours that we emit and that circulate around us? More importantly, can doctors gain knowledge of disease by smelling their patients? Machines that emulate the mammalian nose have picked up the scent of several diseases and may drastically change diagnostic procedure.

Effect of multislice CT technology on scanner productivity

OBJECTIVE

In this study we analyzed the impact of multislice CT technology on scanner productivity in a tertiary care medical center.

MATERIALS AND METHODS

We compared the productivity of two diagnostic CT scanners during the periods January 1 to August 31, 1999 (when both scanners had single-slice CT capability) and January 1 to August 31, 2000 (when one of these scanners was replaced with a multislice CT scanner). The scanners were used primarily for outpatients during the day shift and for inpatients during the evening shift; the demand for CT services was stable. For this analysis, we queried the hospital's radiology information system and identified the number of CT examinations performed during the two analysis periods. We also determined the examination mix, including proportion of enhanced and unenhanced examinations and the anatomic region examined, to ensure comparable patient populations. Statistical analysis was performed.

RESULTS

The number of CT studies performed on the two scanners increased by 1772 (13.1%) from 13,548 (before multislice CT) to 15,320 (when multislice CT was available). The number of examinations enhanced with contrast media increased from 52% to 65%. Between 9:00 A.M. and 5:00 P.M., the number of CT examinations was similar on the single-slice scanners in the two periods (p > 0.05). However, in the period when multislice CT was available, the number of studies performed on the multislice scanner (5919) was 51.9% higher than those performed using the single-slice scanner (3896) (p < 0.0006).

CONCLUSION

Using a multislice CT scanner leads to an increase in CT productivity, even though multislice studies are performed using more complicated protocols than are used on a single-slice CT scanner.

Peroxidase enzyme sensor for on-line monitoring of disinfection processes in the food industry

For desirable environmental reasons, peroxides have replaced halogenated substances for disinfection purposes in the food and beverage industry. However, cost issues and the requirement to remove these agents completely after disinfection necessitate simple, low-cost and sensitive test methods with a wide dynamic range and on-line capability. The development and performance of such a method is detailed here. Low-cost peroxide sensors were fabricated using a single deposition procedure, in which horseradish peroxidase enzyme and dimethylferrocene mediator were entrapped within a cellulose acetate membrane, over the working electrode area of a screen-printed three-electrode assembly. Optimum performance was obtained using HRP and DMFc loadings of 25 U and 0.03 micromol per electrode, respectively, and a mean cellulose acetate molecular weight of 37,000. The device had a detection limit of 49.5 microM hydrogen peroxide and mean RSD values of 21% across the concentration range 49.5-368 microM. In laboratory studies the sensor was shown to have a stability of > or = 4 d in continuous flow-mode maintaining an accuracy of +/- 16% that was considered acceptable for the intended on-line monitoring of the disinfection process. In a field study, it was successfully used on-line within a flow-cell to measure peroxide levels during disinfection of an industrial fermentation vessel.

MRI contrast agents for evaluating focal hepatic lesions

Contrast-enhanced magnetic resonance imaging (MRI) has become an important tool in the detection and characterization of focal hepatic lesions especially when other investigations such as ultrasound (US) and computed tomography (CT) are inconclusive. The purpose of this pictorial review is to briefly summarize the properties of various MRI contrast agents used in hepatic imaging and to highlight their role in evaluation of focal hepatic lesions.

Splenic imaging with ultrasmall superparamagnetic iron oxide ferumoxtran-10 (AMI-7227): preliminary observations

PURPOSE

Ferumoxtran-10 (ultrasmall superparamagnetic iron oxide; Combidex, AMI-7227) is a long-circulating MR contrast agent with reticuloendothelial uptake known to enhance tissue T1 and T2 relaxation rates. The purpose of this study was to assess the effect of ferumoxtran-10-enhanced MRI in evaluating focal splenic lesions.

METHOD

Eighteen patients underwent MR evaluation of the spleen. Two of these patients with exophytic normal splenic tissue (splenules) and 13 of these patients with 24 focal splenic lesions (7 cysts, 2 hemangiomas, 7 metastases, 1 infarct, 7 lymphoma) were assessed by T1-weighted gradient echo and T2-weighted fast SE MRI following intravenous administration of ferumoxtran-10 (1.1 mg of Fe/kg). Qualitative analysis involving improved lesion detection and/or characterization, additional information from postcontrast images affecting staging, and patient management was performed. Quantitative measurements of lesion-to-spleen contrast-to-noise ratio were also performed.

RESULTS

Additional information was provided by ferumoxtran-10-enhanced images in 15 of 18 patients. In 8 of 15 (53%) patients, improved lesion detection (i.e., number of lesions) was obtained on contrast-enhanced images. Improved lesion visualization (i.e., conspicuity) was noted in 11 of 15 (73%) of patients. In 10 of 15 (67%) patients, postcontrast imaging provided additional information leading to lesion characterization. Staging of disease and patient management were affected in 5 of 15 (33%) and 6 of 15 (40%) patients, respectively.

CONCLUSION

Ferumoxtran-10 is a promising contrast agent for the evaluation of focal splenic lesions.

A study of bacterial pathogens in acute pelvic inflammatory disease

The study was carried out on two groups--the study group consisting of 50 women with acute pelvic inflammatory disease and the control group consisting of 20 women admitted for tubal ligation. Pouch of Douglas aspirates were collected under all aseptic precautions with 18 gauge medicut needle. The samples were transferred to thioglycollate broth. A direct Gram staining was done followed by plating on media for aerobic and anaerobic incubation. All cultures were sterile in the control group. There were both monomicrobial (56.7%) and polymicrobial (43.2%) isolates in the study group. The predominant aerobic isolates were coagulase negative Staphylococci, E. coli and Staphylococcus aureus. Amongst anaerobic isolates gram negative bacilli were the most common at 46.6% followed by gram positive cocci at 40%.

Relationship between tumour vascularity and circulating cancer cells in patients with colorectal carcinoma

BACKGROUND

Colorectal cancer vascularity correlates with risk of metastasis. Greater tumour vascularity may increase haematogenous dissemination by providing a larger vessel area for tumour cell invasion into the circulation. We assessed whether the prevalence of tumour cells in the circulation of colorectal carcinoma patients (CTC) increased with tumour vascularity.

METHODS

Pre-operative blood samples were assessed for circulating tumour cells using RT-PCR for carcinoembryonic antigen (CEA) and cytokeratin 20 (CK20) mRNA. Vessel count and volume were morphometrically assessed from tumour biopsies after vasculature staining.

RESULTS

Thirty-three colorectal cancer patients (M:F, 20:13; mean age 66 years, SD 11 years) were studied. One or more blood samples were RT-PCR positive for either CEA or CK20 mRNA or both, in 28 (85%) patients. There were no significant differences in the prevalence of RT-PCR positive patients between high and low tumour vascularity groups, or in tumour vessel counts or volume in RT-PCR positive compared with negative patients.

CONCLUSIONS

These results do not support vascularity related variation in access of tumour cells to the circulation as an explanation for the correlation between tumour vasculature and metastasis. Tumour vascularity and metastatic potential may be linked phenotypes rather than cause and effect.

Dual contrast enhanced magnetic resonance imaging of the liver with superparamagnetic iron oxide followed by gadolinium for lesion detection and characterization

AIM

Iron oxide contrast agents are useful for lesion detection, and extracellular gadolinium chelates are advocated for lesion characterization. We undertook a study to determine if dual contrast enhanced liver imaging with sequential use of ferumoxides particles and gadolinium (Gd)-DTPA can be performed in the same imaging protocol.

MATERIALS AND METHODS

Sixteen patients underwent dual contrast magnetic resonance imaging (MRI) of the liver for evaluation of known/suspected focal lesions which included, metastases (n = 5), hepatocellular carcinoma (HCC;n = 3), cholangiocharcinoma(n = 1) and focal nodular hyperplasia (FNH;n = 3). Pre- and post-iron oxide T1-weighted gradient recalled echo (GRE) and T2-weighted fast spin echo (FSE) sequences were obtained, followed by post-Gd-DTPA (0.1 mmol/kg) multi-phase dynamic T1-weighted out-of-phase GRE imaging. Images were analysed in a blinded fashion by three experts using a three-point scoring system for lesion conspicuity on pre- and post-iron oxide T1 images as well as for reader's confidence in characterizing liver lesions on post Gd-DTPA T1 images.

RESULTS

No statistically significant difference in lesion conspicuity was observed on pre- and post-iron oxide T1-GRE images in this small study cohort. The presence of iron oxide did not appreciably diminish image quality of post-gadolinium sequences and did not prevent characterization of liver lesions.

CONCLUSION

Our results suggest that characterization of focal liver lesion with Gd-enhanced liver MRI is still possible following iron oxide enhanced imaging.Kubaska, S.et al. (2001). Clinical Radiology, 56, 410-415

Dynamic T1-weighted ferumoxides enhanced MRI for imaging liver hemangiomas: preliminary observations

The T1-based signal-enhancing effects of ferumoxides was studied in five liver hemangiomas on short echo-time gradient-recalled echo dynamic magnetic resonance imaging to assess the utility of this technique to image perfusion patterns in liver hemangiomas. We observed peripheral nodular enhancement with centripetal fill in all hemangiomas. Our results suggest that this imaging technique, after rapid injection of ferumoxides, can be used for lesion characterization.

Quantitative and qualitative evaluation of volume of low osmolality contrast medium needed for routine helical abdominal CT

OBJECTIVE

The purpose of our study was to determine the minimum optimal dose of IV contrast medium for helical CT that can preserve image quality while reducing cost.

SUBJECTS AND METHODS

Four hundred sixty-three patients from six centers were enrolled in a prospective trial in which patients were randomized into one of four weight-based dose categories of iopromide, 300 mg I/mL: 1.25, 1.50, 1.75, and 2.0 mL/kg. Six of 463 patients were excluded from analysis. A radiologist at each center who was unaware of the volume of contrast medium administered determined whether the scans were acceptable. The responses were analyzed by dose, in aggregate, and by weight. Enhancement values (in Hounsfield units) in regions of interest in the liver, pancreas, aorta, and kidneys were obtained at a single time during the scan. The participating radiologist was unaware of these values. Finally, three additional nonparticipating site observers assessed the images for acceptability, diagnostic quality, and overall level of confidence. A cost model comparing incurred charges in using 150 or 100 mL, or 1.5 mL/kg, of low osmolality contrast medium was developed from experience in an additional 303 patients.

RESULTS

We found no clinically significant difference in acceptability of scans at doses greater than 1.5 mL/kg. However, significant variability occurred among the centers. The use of 1.5 mL/kg led to a savings of $9927.16 for 303 patients when compared with the use of 150 mL at list price. The cost is the same for 1.5 mL/kg or use of 100 mL of contrast medium.

CONCLUSION

A weight-based dose at 1.5 mL/kg of low osmolality contrast medium can provide acceptable scans in most patients, with a significant cost savings.

Technical cost of CT examinations

PURPOSE

To measure the technical cost of different categories of computed tomographic (CT) examinations.

MATERIALS AND METHODS

For fiscal year 1997, the technical costs of performing CT examinations in a tertiary care academic medical center were measured. Costs were divided into labor and nonlabor categories. Indirect departmental costs were fully allocated according to activity-based methods. Hospital overhead costs were set at 85% of the departmental budget. Physician costs, including those related to image interpretation were not included. The technical cost of CT was determined on a per technical relative value unit (RVU) basis and on a per examination basis. For the latter, the technical cost of nonenhanced CT, contrast material-enhanced diagnostic CT, and interventional CT procedures were determined.

RESULTS

In fiscal year 1997, 45,599 examinations (22,158 [48.6%] abdominal and/or pelvic, 12,115 [26.6%] head and neck, 6,572 [14.4%] thoracic, 1,593 [3.5%] interventional, and 3,161 [6.9%] other) were performed with five CT scanners for a technical RVU output of 254,461. Of 45,599 examinations, 31,007 (68%) were performed with intravenously administered contrast medium. Overall labor costs were $1,744,653, and nonlabor costs were $2,912,282. The cost of a hypothetical CT examination with a mean technical RVU of 5.58 was $189. The overall cost per examination was $150 for nonenhanced CT, $237 for contrast-enhanced CT, and $462 for interventional CT.

CONCLUSION

Although CT is based on sophisticated technology, the mean technical cost of a diagnostic CT examination is less than $200.

A ten channel fibre-optic device for distributed sensing of underground hydrocarbon leakage

With millions of fuel storage tanks and oil pipelines installed around the world, there is inevitably frequent leakage of potentially hazardous hydrocarbons. As many of these installations are below ground, it can often be many years before the extent of the leak is discovered. We have previously reported the development of a sensor for the detection of such subterranean leaks, using infrared reflectometry to interrogate a hydrocarbon sensitive membrane. However, a single sensor cannot provide any information about the flow rate or direction of the leak. This paper describes the extension of the technology to a multi-channel distributed sensing system, using optical fibres capable of distributing the sensors over large subterranean areas. Results are reported from the evaluation of the device, which consisted of monitoring the movement of different hydrocarbons (gasoline, diesel and insulating oil) through a vertical sand-filled vessel.

Efficacy and safety of mangafodipir trisodium (MnDPDP) injection for hepatic MRI in adults: results of the U.S. Multicenter phase III clinical trials. Efficacy of early imaging

The efficacy of contrast-enhanced magnetic resonance imaging (MRI) for detecting and characterizing, or excluding, hepatic masses was assessed in 404 patients, following the intravenous administration of mangafodipir trisodium (MnDPDP) injection, a hepatic MRI contrast agent. An initial contrast-enhanced computed tomography (CT) examination was followed by unenhanced MRI, injection of MnDPDP (5 micromol/kg IV), and enhanced MRI at 15 minutes post injection. Agreement of the radiologic diagnoses with the patients' final diagnoses was higher for enhanced MRI and for the combined unenhanced and enhanced MRI evaluations than for unenhanced MRI alone or enhanced CT using the clinical diagnosis as the gold standard. Mangafodipir-enhanced MRI uniquely provided additional diagnostic information in 48% of the patients, and patient management was consequently altered in 6% of the patients. MnDPDP-enhanced MRI was comparable or superior to unenhanced MRI and enhanced CT for the detection, classification, and diagnosis of focal liver lesions in patients with known or suspected focal liver disease.

Hepatic lesion detection and characterization: value of nonenhanced MR imaging, superparamagnetic iron oxide-enhanced MR imaging, and spiral CT-ROC analysis

PURPOSE

To determine the accuracy for detection and characterization of focal hepatic lesions of nonenhanced, superparamagnetic iron oxide (SPIO)-enhanced, or a combination of nonenhanced and SPIO-enhanced MR imaging and contrast-enhanced spiral computed tomography (CT).

MATERIALS AND METHODS

Spiral CT and T2-weighted SPIO-enhanced (ferucarbotran-enhanced) MR imaging were performed in 35 patients within 2 weeks before surgery for malignant hepatic lesions. Only malignant lesions with histopathologic proof were considered. A total of 875 images with and 800 images without focal lesions were presented to five readers, who were asked to assess the presence and characterization of lesions by using a five-point confidence scale. Receiver operating characteristic analysis was performed.

RESULTS

Nonenhanced and SPIO-enhanced images together and SPIO-enhanced images alone yielded the best performance for lesion detection. No differences were found among all imaging techniques with regard to lesion characterization (benign vs malignant). The combined approach resulted in larger area under the ROC curve (A(z) = 0.9062) and accuracy (85.3%) (P < 0.02), as compared with SPIO-enhanced MR imaging (A(z) = 0.8667; accuracy, 73.1%).

CONCLUSION

SPIO-enhanced T2-weighted MR imaging was more accurate than nonenhanced T1-weighted and T2-weighted MR imaging and contrast-enhanced spiral CT for the detection of focal hepatic lesions. The combined analysis of nonenhanced and SPIO-enhanced images was more accurate in the characterization of focal hepatic lesions than was review of SPIO-enhanced images alone.

Multicentre dose-ranging study on the efficacy of USPIO ferumoxtran-10 for liver MR imaging

AIM

A dose ranging multicentre phase-II clinical trial was conducted to evaluate the efficacy of ultrasmall superparamagnetic iron oxide (USPIO) ferumoxtran-10 for magnetic resonance (MR) imaging of focal hepatic lesions.

MATERIAL AND METHODS

Ninety-nine patients with focal liver lesions received USPIO at a dose of 0.8 (n = 35), 1.1 (n = 32), or 1.7 (n = 32) mg Fe/kg. Liver MR imaging was performed before and after USPIO with T1-weighted and T2-weighted pulse sequences. Images were analysed by two independent readers for additional information (lesion detection, exclusion, characterization and patient management). Signal intensity (SI) based quantitative measurements were also taken.

RESULTS

Post-contrast medium MR imaging showed additional information in 71/97 patients (73%) for reader one and 83/96 patients (86%) for reader two. The results with all three doses were statistically significant (P < 0.05). Signal intensity analysis revealed that all three doses increased liver SI on T1-weighted images and decreased liver SI on T2-weighted images. On T2-weighted images metastases increased in contrast relative to normal hepatic parenchyma whereas haemangiomas decreased in contrast. On T2-weighted images there was statistically improved efficacy at the intermediate dose, which did not improve at the highest dose.

CONCLUSION

Ultrasmall superparamagnetic iron oxide was an effective contrast agent for liver MR imaging at all doses and a dose of 1.1 mg Fe/kg was recommended for future clinical trials.

Technical cost of radiologic examinations: analysis across imaging modalities

PURPOSE

To determine the individual technical costs of general diagnostic radiographic, ultrasonographic (US), computed tomographic (CT), magnetic resonance (MR) imaging, and scintigraphic examinations and interventional radiology.

MATERIALS AND METHODS

The Radiology Cost and Productivity Benchmarking Study method of the University HealthSystem Consortium, a cooperative group of academic medical centers, was modified and extended to the six imaging modalities in a tertiary care academic setting. Hospital billing and cost records were analyzed for fiscal year 1996. Costs were divided into labor and nonlabor categories and were allocated to individual imaging modalities on the basis of resources consumed. Physician cost and hospital overhead were not included. Unit costs were analyzed per technical relative value unit (RVU) and per examination.

RESULTS

The costs per technical RVU for diagnostic radiography, US, CT, MR imaging, scintigraphy, and interventional radiology were $65. 06, $28.74, $20.95, $17.69, $42.19, and $89.03, respectively. The technical costs per examination for diagnostic radiography, US, CT, MR imaging, scintigraphy, and interventional radiology were $41.92, $50.28, $112.32, $266.96, $196.88, and $692.60, respectively.

CONCLUSION

The method of unit cost analysis for individual imaging modalities was successfully tested in a tertiary care setting. The method should be adopted to allow cost comparison across many institutions, which will permit the promotion of best practices.

Safety and efficacy of mangafodipir trisodium (MnDPDP) injection for hepatic MRI in adults: results of the U.S. multicenter phase III clinical trials (safety)

The short-term safety of mangafodipir trisodium (MnDPDP) injection was studied in 546 adults with known or suspected focal liver lesions. An initial contrast-enhanced computed tomography examination was followed by unenhanced magnetic resonance imaging (MRI), injection of MnDPDP (5 micromol/kg), and enhanced MRI. Adverse events were reported for 23% of the patients; most were mild to moderate in intensity, did not require treatment, and were not drug related. The most commonly reported adverse events were nausea (7%) and headache (4%). The incidence of serious adverse events was low (nine events in six patients) and not drug related. Injection-associated discomfort was reported for 69% of the patients, and the most commonly reported discomforts included heat (49%) and flushing (33%). Changes in laboratory values and vital signs were generally transient, were not clinically significant, and did not require treatment. There were no clinically significant short-term risks from exposure to MnDPDP.