Clinical Comparison of 99Tcm-Hmpao Labelled Leucocytes and 99Tcm-Nanocolloid in the Detection of Inflammation

Forty-five patients with various inflammatory diseases were imaged with 99Tcm-HMPAO labelled leucocytes and 99Tcm-nanocolloid within 7 days. The overall sensitivity of 99Tcm-leucocytes was 97% and that of 99Tcm-nanocolloid 59% and both agents had a 100% specificity. The 99Tcm-leucocyte method showed reliable results in various inflammatory and infectious conditions, and seems suitable as a primary imaging method. On the contrary, 99Tcm-nanocolloid cannot be recommended for use in inflammatory bowel diseases, soft tissue abscesses or prosthetic vascular graft infections. However, 99Tcm-nanocolloid gave reliable information in inflammatory and infectious bone and joint diseases in which it had a 90% sensitivity and 100% specificity. In those lesions the 99Tcm-nanocolloid method may be useful, because it is simple, fast and cheap. Yet, further evaluation is needed.

Ultraviolet Light Inactivation of Murine Norovirus and Human Norovirus GII: PCR May Overestimate the Persistence of Noroviruses Even When Combined with Pre-PCR Treatments

Transmission of gastroenteritis-causing noroviruses may be significant via contaminated surfaces. Measures for control, e.g. disinfection with ultraviolet irradiation (UV), are therefore necessary for interrupting this transmission. Human norovirus (HuNoV) GII.4 and Murine norovirus (MuNoV) were used to study the efficacy of UV for virus inactivation on dry glass surfaces. MuNoV inactivation was measured using viability assay and the reduction in viral RNA levels for both viruses using reverse transcription quantitative PCR (RT-QPCR). For each UV dose, two parallel sample groups were detected using RT-QPCR: one group was enzymatically pre-PCR treated with Pronase and RNAse enzymes, while the other was not treated enzymatically. In the viability assay, loss of infectivity and a 4-log reduction of MuNoV were observed when the viruses on glass slides were treated with a UV dose of 60 mJ/cm(2) or higher. In the RT-QPCR assay, a steady 2-log decline of MuNoV and HuNoV RNA levels was observed when UV doses were raised from 0 to 150 mJ/cm(2). A distinct difference in RNA levels of pretreated and non-pretreated samples was observed with UV doses of 450-1.8 × 10(3) mJ/cm(2): the RNA levels of untreated samples remained over 1.0 × 10(3) PCR units (pcr-u), while the RNA levels of enzyme-treated samples declined below 100 pcr-u. However, the data show a prominent difference between the persistence of MuNoV observed with the infectivity assay and that of viral RNA detected using RT-QPCR. Methods based on genome detection may overestimate norovirus persistence even when samples are pretreated before genome detection.

A practice-based study of the variation of diagnostics of dental caries in new and old patients of different ages

Data mining of digital dental records provides possibilities for analysing the variation between dentists when diagnosing caries. A total of 71,317 male and 82,302 female subjects visited the health centres in Vantaa and Kemi during the 'digital era' (1994-2005). As subjects were classified as 'new patients' at the first examination, all re-examinations of the same subjects thereafter by the same dentist produced 'old patients'. A mean number of decayed surfaces (DS) was counted as a function of the age of the subject during the follow-up. The significance of the difference between old and new patients was determined by the Mann-Whitney test for each age cohort at the cross sections, and for the whole follow-up. Caries was seen to affect new patients more than the old ones in both health centres after the age of 20 years. The mean DS values were the same, reaching about 1 for new and old patients at the age of 15 years. The mean DS had a peak for new patients in both health centres at the age of 25 years and another peak around 45-50 years in Kemi. With a few exceptions there was a significant difference between the DS values of new and old patients at most cross sections and for the whole follow-up time. Evidently dentists examine new patients more carefully than their old patients. After the age of 18 years patients may have changed their dentists because they have finished the free-of-charge treatment period.

Effect of clinical audits of radiation use in one hospital district in Finland

BACKGROUND

A clinical audit is a systematic, independent, and documented process to improve the quality of radiological processes and radiation safety for patients.

PURPOSE

To evaluate the effect of an audit process by comparing the results of two consecutive audits at the same units.

MATERIAL AND METHODS

Audits were carried out twice at each imaging unit in the southwest hospital district of Finland: first, at the end of 2003, and again in November 2007. Both evaluations were carried out in a similar way: by interviewing personnel and examining documents, independent experts from other hospital districts ensured that diagnostic medical imaging processes at each unit were carried out according to generally accepted standards for good medical radiological procedures. The results of the consecutive audits were compared in order to analyze the effects of the clinical audits.

RESULTS

The use of radiation was in accordance with the requirements and standards of good medical procedures at every audited unit during both evaluations. The list of audit criteria was fulfilled satisfactorily on both occasions at all of the audited units, and clearly better during the second run. In the first audit, the auditors made 80 recommendations for improving diagnostic procedures and, in the second audit, 53 recommendations. During the first audit, most of the recommendations (22/80) concerned instructions in the fundamental practice of examining a patient. During the second audit, most recommendations were in the category of radiation doses.

CONCLUSION

The clinical audit had a positive impact on the practice of work procedures in radiological departments. Most of the recommendations made after the first audit had been taken into consideration by the time of the second audit.

Data transmission in dental identification of mass disaster victims

Dental evidence, especially from radiographs, has been found to be an effective method in personal identification. Previously, it has been shown that wireless personal digital assistants (PDA) can be used to transfer digitized radiographs. The purpose of this study was to set up a secure and reliable mobile connection for transferring dental digital images for disaster victim identification, and to test this new way of working in Phuket, Thailand, following the December 2004 Asian Tsunami disaster.

MATERIAL AND METHODS

Digital dental radiographs and clinical images were transferred in two separate sets using secured data transmission from a server in Finland to PDA terminals in Thailand. The mean size of the images in test 1 and test 2 were 90.7 kB and 88.1 kB, respectively.

RESULTS

The mean speed of the transmission was 3.7 kB/s with the Nokia 9500 and 3.4 kB/ s with the Qtek 2020i. The quality of all the pictures was found to be good enough for dental identification purposes.

CONCLUSIONS

Wireless personal digital assistants (PDA) together with data secure transmission of digital clinical information could be used in order to assist in disaster victim identification in areas where GSM cellular networks are available.

Role of laparoscopy and laparoscopic ultrasound in staging of pancreatic tumours

BACKGROUND AND AIMS

Radiological imaging alone is not reliable enough in staging of pancreatic cancer. Not only because of poor sensitivity but also because there is a tendency to overstage tumours. The aim of the study was to compare the efficiency of spiral computed tomography (CT), transabdominal ultrasound (US), laparoscopy (LAP) and laparoscopic ultrasound (LUS) in staging of pancreatic tumours.

MATERIAL AND METHODS

In this prospective study 27 patients underwent pancreatic tumour staging with CT, US, LAP and LUS. The reference standard was operative evaluation or in case of disseminated disease laparoscopic assessment.

RESULTS AND CONCLUSIONS

Although LAP was hindered by adhesions in 11% of the patients the benefit of LAP staging was evident in detecting peritoneal carcinomatosis. The assessment of the local tumour expansion of a pancreatic carcinoma was difficult for all staging modalities. LUS did not change the decision whether to proceed with laparotomy once. In our experience routine use of laparoscopic staging does not benefit patients with pancreatic tumour but in selected cases it may prevent unnecessary laparotomy.

The effect of haemosiderosis and blood transfusions on the T2 relaxation time and 1/T2 relaxation rate of liver tissue

Patients with chronic anaemia need repeated blood transfusions, which eventually lead to iron overload. The excess iron from blood transfusions is deposited in the reticuloendothelial system and in the parenchymal cells of the liver, spleen and other organs. Cellular damage is likely to occur when iron overload in the liver is pronounced. Liver biopsy is still necessary to evaluate the degree of haemosiderosis or haemochromatosis. To avoid this invasive procedure, methods have been sought to determine the concentration of iron in liver tissue and to estimate the effect of the treatment of haemosiderosis or haemochromatosis. In this MRI study, the T2 relaxation time and the 1/T2 relaxation rate of liver were determined in 23 patients who had undergone repeated blood transfusions for chronic anaemia. The first 60 transfusions had the greatest influence on the measured T2 relaxation time, with T2 relaxation time decreasing as haemosiderosis progresses. The 1/T2 relaxation rate increases significantly in a linear fashion when the number of blood transfusions increases up to 60. After 60 transfusions the influence of additional blood transfusions on the T2 value was minimal; the same response, although in reverse, was seen in the 1/T2 relaxation rate curve. One possible explanation for this may be that the MR system could detect the effect of only a limited amount of iron excess and any concentration over this limit gives a very short T2 relaxation time and a very weak signal from the liver, which is overwhelmed by background noise. However, in mild and moderate haemosiderosis caused by blood transfusions, T2 relaxation time and 1/T2 relaxation rate reflect iron accumulation in liver tissue.

Ulcerative colitis and colorectal carcinoma: DNA-profile, laminin-5 gamma2 chain and cyclin A expression as early markers for risk assessment

BACKGROUND

Ulcerative colitis patients are at increased risk for developing colorectal carcinomas. Despite expensive surveillance programmes, clinical practice reflects an uncertainty in individual risk assessment. The aim of the study was to evaluate independent cellular features with possible predictive value.

METHODS

Two patient groups were selected: group A comprised 8 patients with ulcerative colitis-associated colorectal carcinomas, group B comprised 16 ulcerative colitis patients with risk factors (duration of disease, extent of inflammation, epithelial dysplasias). A total of 683 paraffin-embedded mucosal biopsies were retrospectively evaluated for inflammatory activity, grade of dysplasia, ploidy status, laminin-5 gamma2 chain and cyclin A expression.

RESULTS

Mild or moderate inflammatory activity was present in 78% of all biopsies, low- or high-grade dysplasia in 5.5%. There was no difference in inflammatory activity and dysplasia between patient groups. In group A, 75% of the biopsies exhibited aneuploid DNA distribution patterns. Group B showed mainly proliferative-diploid cell populations (85% / P = 0.006). Laminin-5 gamma2 chain was expressed in 13% of all biopsies, with a higher frequency in group A (P = 0.002). Cyclin A expression was found in 98% of all biopsies, with a higher number of immunopositive cells in group A biopsies (P = 0.014).

CONCLUSIONS

Combined nuclear DNA assessment, laminin-5 gamma2 chain and cyclin A expression may help to identify ulcerative colitis patients with an increased risk for cancer development.

Evaluation of surface contamination and the presence of Listeria monocytogenes in fish processing factories

The main objective of this study was to determine the level of surface contamination in fish processing factories and the presence of Listeria in the factory environment and products. Another objective was evaluation of the different hygiene-monitoring methods. Total aerobic heterotrophic and enterobacteria, yeast and mold samples were collected and ATP levels measured in 28 factories. The number of well or adequately washed and disinfected factories was small (2 of 28), in terms of total aerobic heterotrophic bacterial counts on the surfaces. Most surfaces contaminated with bacteria were heavily contaminated. Results of the ATP and the total bacteria contact agar slide methods were poorly correlated (r = 0.21) although 68% of the samples were categorized as good to moderate or unacceptable with both methods. The Listeria-positive surface samples usually contained increased numbers of total bacteria (70.9%). The contamination of products and raw fish together with Listeria spp. was 45% and with Listeria monocytogenes 12%. Cold smoked fish was the most contaminated, with 75% Listeria spp. and cold salted fish with 20% L. monocytogenes. Listeria innocua was found in the samples more than twice as often as L. monocytogenes.

Validation of the microbiological methods hygicult dipslide, contact plate, and swabbing in surface hygiene control: a Nordic collaborative study

A collaborative study on total aerobic bacterial count was conducted to validate the Hygicult TPC dipslide against contact plates and swabbing, using stainless-steel surfaces artificially contaminated with different microbes at various levels. Twelve laboratories took part in the validation procedure. The total number of collaborative samples was 108. The microbial level in each sample was assessed in triplicate using the 3 above-mentioned methods under 3 different incubation conditions (at 25 +/- 1 degrees C for 48 and 72 h and at 30 +/- 1 degrees C for 48 h). Surface sampling methods detached 25-30% at the lowest (theoretical yield, 1.4 cfu/cm2), 18-20% at the middle (theoretical yield, 10.7 cfu/cm2), and 16-21% at the highest (theoretical yield, 43.6 cfu/cm2) levels of microbes from the test surfaces. The percentage of acceptable results after removing outliers was 89%. Repeatability standard deviations ranged from 27.2 to 74.6% and reproducibility standard deviations ranged from 42.1 to 97.5%. There were no significant differences between results obtained at different incubation temperatures (25 and 30 degrees C) or incubation times (48 and 72 h) for all 3 methods. The Hygicult TPC dipslide, contact plate, and swabbing methods gave similar results at all 3 microbial levels tested: 0.35-0.43 cfu/cm2 at the lowest level, 1.9-2.2 cfu/cm2 at the middle level, and 7.1-9.1 cfu/cm2 at the highest level.

Cancer of the vagina: Laminin-5gamma2 chain expression and prognosis

The purpose of this experiment was to investigate the expression and the prognostic impact of the gamma2 subchain of laminin-5 in vaginal malignancies. The outcome of the rare disease primary carcinoma of the vagina is poor and little is known about prognostic markers. The gamma2 chain of laminin-5, an epithelial basement membrane protein, is thought to play a crucial role in tumor cell adhesion, migration, and proliferation, and may thus be an additive potential marker. Archival, paraffin-embedded sections were stained immunohistochemically with an antibody against the gamma2 chain of human laminin-5 protein. The material consisted of 59 cases of primary vaginal malignancies, subdivided into short- and long-time survivors. All invasive malignancies of epithelial origin were positively stained with the antibody against the gamma2 chain. High expression of the gamma2 chain correlated significantly in an univariate analysis with short-time survival (P = 0.041), but in the multivariate analysis only age and tumor size were independent prognostic factors. A significant intercorrelation between large tumors and high gamma2 chain immunoreactivity was found (P = 0.003). These results indicate that laminin-5gamma2 subchain expression in primary vaginal carcinomas is of prognostic impact. However, in a multivariate analysis only patient age and tumor size had independent prognostic value.

Chain specificity assignment of monoclonal antibodies to human laminins by using recombinant laminin beta1 and gamma1 chains

In the present study, the chain specificity of 16 commonly used monoclonal antibodies to human laminin(s) was analysed by using recombinant laminin beta1 and gamma1 chains. By ELISA, all antibodies reacted with purified placenta laminin, and most antibodies recognised either recombinant beta1 or gamma1 chains. Reactivity and chain specificity was confirmed against the recombinant chains in Western blotting under non-reducing conditions, and only a few antibodies were reactive under reducing conditions. Most antibodies were able to immunoprecipitate associated laminin beta1/gamma1 chains from platelet lysates. Based on these results and data from the literature, a tentative epitope map is presented.

Laminin-5 as a marker of invasiveness in cervical lesions

BACKGROUND

Treatment decisions for cervical cancer, a common disease worldwide, depend on demonstrating whether or not tumor invasion of the surrounding tissue has occurred. Invasion can be difficult to assess by standard histopathologic methods, especially when limited amounts of tissue are available. Several studies of a variety of cancers have reported increased expression of laminin-5-an important attachment protein for epithelial cells-in invasive carcinomas. This study was designed to investigate whether the presence of laminin-5 is related to the invasive capacity of cervical lesions.

METHODS

We used immunohistochemical methods to stain archival, paraffin-embedded sections of cervical lesions with a polyclonal antibody specifically targeting the gamma2 chain of human laminin-5 protein. The study sample included 23 lesions of mild and moderate dysplasia (cervical intraepithelial neoplasia [CIN] 1 and 2, respectively), 32 lesions of severe dysplasia or carcinoma in situ (CIN 3), 15 lesions of microinvasive cancer, and 20 lesions of frankly invasive cancer. Cellular proliferative activity was also investigated by the use of monoclonal MIB-1 (directed against the antigen Ki-67) and anticyclin A antibodies.

RESULTS

Invasiveness of cervical lesions was positively associated with immunohistochemical staining of the gamma2 chain of laminin-5 (two-sided P =.001). All CIN 1 and CIN 2 lesions-except one CIN 2 lesion later shown to be invasive cancer-and 21 CIN 3 lesions tested negative for the gamma2 chain of laminin-5. Eleven CIN 3 lesions and all invasive cancers tested positive for this protein. One lymph node metastasis and a pleural metastasis from one of the patients with invasive cancer showed strong immunohistochemical positivity. Proliferative activity increased with advancement of the lesion but was not confined to cells positive for the gamma2 chain of laminin-5.

CONCLUSIONS

These data suggest that antibodies directed against the gamma2 chain of laminin-5 can identify cervical lesions with invasive capacity and thus may be useful as a sensitive marker of early invasion.

Expression of the laminin gamma2 chain in different histological types of lung carcinoma. A study by immunohistochemistry and in situ hybridization

Sixty-four malignant lung tumours and 12 of their regional lymph node metastases were analysed for expression of the laminin gamma2 chain by immunohistochemistry and in situ hybridization. Expression of the laminin gamma2 chain was strongest in squamous cell carcinomas, followed by adenocarcinomas and large cell carcinomas. Positive cells, except for large cell carcinomas, were located at the epithelial-stromal interface of tumour clusters. An important exception was small cell lung carcinoma, with only a low level of laminin gamma2 chain expression. Apart from tumour type, this may reflect the relatively scanty fibrous stroma in these tumours and supports previous observations that small cell lung carcinoma cells, contrary to other types, lack surface expression of alpha(6)beta(4) integrin, the specific laminin-5 binding receptor. In frozen sections, immunohistochemistry showed linear basement membranes around tumour clusters in squamous cell carcinomas and adenocarcinomas. This shows that carcinoma cells are capable of heavy deposition of the laminin gamma2 chain around tumour clusters and suggests that a laminin gamma2 chain-containing substrate may be of significance for the spread and growth of malignant tumours.

Automatic detection of frequency changes depends on auditory stimulus intensity

OBJECTIVE

A cortical cognitive auditory evoked potential, mismatch negativity (MMN), reflects automatic discrimination and echoic memory functions of the auditory system. For this study, we examined whether this potential is dependent on the stimulus intensity.

DESIGN

The MMN potentials were recorded from 10 subjects with normal hearing using a sine tone of 1000 Hz as the standard stimulus and a sine tone of 1141 Hz as the deviant stimulus, with probabilities of 90% and 10%, respectively. The intensities were 40, 50, 60, 70, and 80 dB HL for both standard and deviant stimuli in separate blocks.

RESULTS

Stimulus intensity had a statistically significant effect on the mean amplitude, rise time parameter, and onset latency of the MMN.

CONCLUSION

Automatic auditory discrimination seems to be dependent on the sound pressure level of the stimuli.

Laminin-5 promotes adhesion and migration of epithelial cells: identification of a migration-related element in the gamma2 chain gene (LAMC2) with activity in transgenic mice

The effects of laminin-5 and its subunit gamma2 chain on cell adhesion and migration were studied, and a migration-related cis-acting element was identified in the gamma2 chain gene (LAMC2) using promoter-reporter gene constructs in transgenic mice. Intact laminin-5 molecules, but not recombinant gamma2 chain promoted cell adhesion of human keratinocytes and mouse squamous carcinoma cells, indicating that the gamma2 chain does not contain a cellular binding site. However, the gamma2 chain as such is probably involved in the process of cell locomotion, as antibodies against the short arm of the chain inhibited migration of carcinoma cells in an in vitro assay. Further evidence for the involvement of the gamma2 chain in cell migration was obtained by the identification of a cis-acting element in a promoter-lacZ reporter gene construct that was active in migratory epithelial cells of healing wounds in mice made transgenic by microinjection of the construct into fertilized oozytes. The migration active element was located in the sequence between -613 and +55. The same construct, and another one containing 5900 base pairs of the 5' flanking region, yielded very limited expression in cells of normal tissues. The limited expression was, however, only observed in epithelial cells of different tissues, i.e. cell types that normally express laminin-5 in vivo. The results show that the sequence between -613 and +55 contains elements that can drive expression during epithelial cell migration and that also partially confers more general epithelium expression. However, elements outside -5900 and +55 are needed for normal epithelium expression of the LAMC2 gene.

Performance evaluation of disinfectant formulations using poloxamer-hydrogel biofilm-constructs

Poloxamer F127 is a di-block co-polymer of polyoxyethylene and polyoxypropylene. Aqueous solutions show thermo-reversible gelation, being liquid at temperatures < 15 degrees C and robust gels at temperatures > 15 degrees C. Chilled poloxamer solutions (30% w/v) were inoculated with approximately 10(4-5) cfu ml-1 of stationary phase cultures of Pseudomonas aeruginosa, Ps. fluorescens, Pantoea agglomerans, Micrococcus luteus, Staphylococcus epidermidis, Bacillus subtilis or Listeria innocua. Drops (200 microliters) of the inoculated poloxamers were placed on stainless steel coupons held in Petri dishes containing moistened cotton wool and incubated at 30 degrees C for 5 h. All strains grew well giving between 10(6-7) cfu ml-1 at 5-6 h. The cultured gels were readily applied to tests of biocide effectiveness as the stainless steel coupons could be removed and flooded with biocide solution for fixed exposure times. Provided that the temperature of the biocide solutions was > 15 degrees C, the integrity of the gels could be maintained during exposure. After exposure, the gels and their supports were removed to separate tubes containing neutralizer solution (< 15 degrees C). The gels rapidly dispersed within 5 min to ensure a complete recovery of the sample population. Biofilm-constructs and cell suspensions (10(7) cfu ml-1) were exposed to four commercial disinfectant formulations, based on hypochlorite, alcohol, hydrogen peroxide and a tenside, at recommended use levels. Cell suspensions, in the presence of bovine serum albumen (BSA; 0.03% w/v), were subject to a > 5-log kill within 5 min while the killing effected against the biofilm-constructs varied between 0.4 and 2-log reductions. The results indicate a high degree of reproducibility between replicate samples, with patterns of susceptibility varying both as a function of organism, biocide type and concentration. The experiments strongly support the view that poloxamer-constructs are suitable for application in trials and testing of disinfectant formulations.

Effect of obesity on the response to insulin therapy in noninsulin-dependent diabetes mellitus

An initial improvement in glycemic control is often followed by gradual deterioration of glycemia during insulin treatment of patients with noninsulin-dependent diabetes mellitus (NIDDM). We examined the causes of such worsening in a 12-month follow-up analysis of 100 insulin-treated NIDDM patients in the Finnish Multicenter Insulin Therapy Study who were treated with either combination therapy with insulin or insulin alone. In the entire study group, glycemic control averaged 9.7 +/- 0.2% at 0 months and 8.0 +/- 0.1%, 8.0 +/- 0.1%, 8.2 +/- 0.1%, and 8.5 +/- 0.2% at 3, 6, 9, and 12 months (P < 0.001 for each time point vs. 0 months). Glycemic control at 12 months was significantly worse than that at 3 (P < 0.001), 6 (P < 0.001), and 9 months (P < 0.02). Baseline body mass index was the most significant predictor of deterioration in glycemic control. During 1 yr, hemoglobin A1c decreased almost 3-fold more (by 1.7 +/- 0.2%; P < 0.001 vs. 0 months) in patients whose baseline weight was below the mean baseline body mass index of 28.1 kg/m2 (nonobese patients) than in those whose weight exceeded 28.1 kg/m2 (obese patients; 0.5 +/- 0.2%; P = NS vs. 0 months; P < 0.01 vs. obese patients). Glycemic control improved similarly over 1 yr in the nonobese subjects and deteriorated similarly in the obese patients regardless of their treatment regimen. Insulin doses, per body weight, were similar in the nonobese and obese patients. The nonobese patients consistently gained less weight during 12 months of combination therapy with insulin (3.5 +/- 0.6 kg at 12 months) than during insulin therapy alone (5.1 +/- 0.6 kg; P < 0.05). The treatment regimen did not influence weight gain in the obese group, who gained 4.4 +/- 1.0 kg during combination therapy with insulin and 4.5 +/- 1.1 kg during insulin therapy alone. We reached the following conclusions: 1) after an initial good response, glycemic control deteriorates more in obese than in nonobese patients with NIDDM; 2) in obese patients, weight gain per se cannot explain the poor glycemic response to combination or insulin therapy, but it may induce a disproportionately large increase in insulin requirements because of greater insulin resistance in the obese than in the nonobese; 3) in nonobese patients, glycemic control improves equally during 1 yr with combination therapy with insulin and insulin alone, but combination therapy with insulin is associated with less weight gain than treatment with insulin alone; 4) weight gain appears harmful, as it is associated with increases in blood pressure and low density lipoprotein cholesterol.

Altered distribution and synthesis of laminin-5 (kalinin) in oral lichen planus, epithelial dysplasias and squamous cell carcinomas

Laminin-5 is a glycoprotein which mediates epithelial cell adhesion to the basement membrane. This study describes the distribution and synthesis of laminin-5 in oral lichen planus, epithelial dysplasias, squamous cell carcinomas and a lymph node metastasis using immunohistochemistry and in situ hybridization. In normal oral mucosa and lichen planus, immunoreaction to the laminin-5 was seen as a thin continuous, delicate line in the basement membrane region, although slight irregularities in the thickness and intensity of the immunoreaction could be detected in some cases with lichen planus. In epithelial dysplasias, the laminin-5 staining was discontinuous and more diffuse compared to lichen planus and normal mucosa. The immunoreaction was generally extracellular, although in some cases with lichen planus and epithelial dysplasia there were a few basal epithelial cells showing cytoplasmic staining. The invasive carcinomas and the lymph node metastasis showed a striking, intense cytoplasmic, staining of the carcinoma cells along the invasive border of the neoplastic islands and in individual infiltrating carcinoma cells. Using in situ hybridization, the laminin-5 gamma 2 chain mRNA expression could not be detected in normal oral mucosa whereas, in non-dysplastic lichen planus and, more strongly, in dysplasias, there was a clear increase in the expression of laminin-5 mRNA in the basal epithelial cells. The most intensive signal was detected in the invasive front of the oral squamous cell carcinomas and the lymph node metastasis. We conclude that, in oral squamous cell carcinoma, there is altered synthesis and secretion of laminin-5 mRNA and protein. It is also evident that in dysplastic lesions of oral epithelium the synthesis and distribution of laminin-5 is abnormal.

Effect of fasting and food intake on magnetization transfer of human liver tissue

Magnetization transfer (MT) technique is a promising method in differential diagnosis of diseases in parenchymal tissues. Basic knowledge about circumstances and elementary factors that influence MT and its parameters is still insufficient, however. Having a meal before the magnetic resonance (MR) examination could change liver MT parameters compared to fasting state through alteration in liver perfusion, blood flow, and content of portal blood (proteins and other derivates from a meal). If MT parameters can be altered by a meal, then MR liver studies should always be performed after fasting. Before MRI examinations we examined three healthy volunteers after a high-fat meal with Doppler ultrasound technique to find out duration and magnitude of changes in portal blood flow. Duration of > or = 50% increased peak-flow value compared to fasting state in portal vein was > 90 min, which is enough for our MR examination. With a low-field 0.1-T MR imager we examined 10 healthy volunteers after a short (range from 3 h 45 min to 17 h 30 min) fast and also immediately after a high-fat meal. Magnetization transfer parameters, magnetization transfer ratio (MTR) and magnetization transfer rate Rwm of liver tissue were determined. MTR changed significantly (Student paired two-tailed t-test, p = .0044) after a meal, but Rwm did not (p = .0952). We recommend a 4 h fast before MR examination that aims to determine the MTR of liver tissue.

Urokinase plasminogen activator is expressed by basal keratinocytes before interstitial collagenase, stromelysin-1, and laminin-5 in experimentally induced dermatitis herpetiformis lesions

We studied the temporal expression of interstitial collagenase, stromelysin-1 and -2, and urokinase plasminogen activator (uPA) mRNAs by in situ hybridization in eight patients with dermatitis herpetiformis. To induce blisters, 50% potassium iodide patch tests were performed, and serial biopsy specimens were taken at 4, 12, and 24 h. Additional samples were taken from occasional spontaneous blisters. Components of the basement membrane, laminin-5, laminin-1, and type VII collagen, were examined immunohistochemically in relation to matrix metalloproteinase expression. At 12 h, when no blisters were seen, uPA mRNA was present in basal keratinocytes in five of eight samples, whereas interstitial collagenase and stromelysin-1 mRNA were not detected. At this time, immunohistochemistry failed to show changes in the basement membrane. At 24 h, uPA, collagenase, and stromelysin-1 mRNAs were present in basal keratinocytes, suggesting an activation of latent forms of the two latter enzymes by the uPA-plasmin pathway. Signal for stromelysin-2 was not detected. Furthermore, disruptions of laminin-1 and type VII collagen were evident. The data suggest that stromelysin-1 and interstitial collagenase may contribute to the degradation of basement membrane in dermatitis herpetiformis. Intracellular staining for laminin-5 co-localized with collagenase mRNA in basal keratinocytes. Because laminin-5 is essential for adhesion of keratinocytes to basement membrane and for establishment of focal adhesions on migrating cells, its production may reflect a regenerative response after the destruction of basement membrane components.

Expression of the laminin gamma 2 chain in pancreatic adenocarcinoma

Forty-two pancreatic adenocarcinomas were investigated immunohistochemically and by in situ hybridization for the expression of the laminin gamma 2 chain. In 41 cases, intracytoplasmic immunoreactivity for the gamma 2 chain was seen. Positive tumour cells were located especially at the epithelial-stromal interface of the tumour cell islands. In 22 cases, diffuse laminin gamma 2 chain immunoreactivity could also be seen in stroma and in seven cases, occasional positivity was detected in the neoplastic basement membranes. Signals for laminin gamma 2 chain mRNA in tumour cells displayed a distribution similar to that observed on immunohistochemistry. There were significantly more cases with less than 20 per cent of laminin gamma 2 chain-positive tumour cells in tumours extending to peripancreatic tissues and/or tumours with regional or distant metastases (p = 0.029). A corresponding statistical significance could also be noted in the mRNA level (P = 0.025). The results show that pancreatic adenocarcinomas display a high activity of laminin gamma 2 chain synthesis. Tumours with a strong laminin gamma 2 chain synthesis show a lower invasive and metastatic potential than tumours with a weak or moderate laminin gamma 2 chain expression.

Laminin-5 is a marker of invading cancer cells in some human carcinomas and is coexpressed with the receptor for urokinase plasminogen activator in budding cancer cells in colon adenocarcinomas

Recombinant human gamma 2 chain of laminin-5 was expressed in Escherichia coli, and used to generate specific polyclonal antibodies which were used to study the distribution of the protein in human cancers. A total of 72 biopsies of human cancers were stained, including 23 cases of colon adenocarcinomas, 16 ductal breast carcinomas, 9 malignant melanomas, 14 squamous cell carcinomas of the skin and cervix, and 10 sarcomas. As a control for the specificity of the antibodies, we performed in situ hybridization on adjacent sections of a number of the cases, and in all of these cases the localization of the gamma 2 chain protein and mRNA was identical. We found gamma 2 chain immunoreactivity in cancer cells in all cases of colon adenocarcinomas and squamous cell carcinomas but not in any of the sarcomas, supporting the view that the laminin-5 protein is specific for cells of epithelial origin. Notably, in all of the cases of colon adenocarcinomas, the positive staining was invariably associated with budding cancer cells located at the tip of invading malignant epithelium, whereas the cancer cells deeper in the tumors were most often negative. The staining was cytoplasmic in all cases and only in one case did we see additional extracellular immunoreactivity, indicating that this laminin isoform in cancer tissue is not laid down in the extracellular matrix but probably exerts its function at the cell surface or in its immediate vicinity. Using in situ hybridization to analyze the coexpression of laminin-5 and components of the plasminogen activation system, we found that the histological distribution of laminin-5-positive budding cancer cells at the invasion front in colon adenocarcinomas was identical to that of the receptor for urokinase-type plasminogen activator. These findings suggest that laminin-5 is a marker of invading cancer cells in at least some human malignancies, and that it therefore might represent a valuable marker for the invasive potential of these cancers. The colocalization of laminin-5 and urokinase-type plasminogen activator receptor in a subset of cancer cells in colon cancer also suggests that a controlled up-regulation of a number of gene products is a characteristic of budding colon cancer cells, and that these gene products serve functions crucial for the invasive phenotype of these cancer cells.

A microbiological screening method for the indication of irradiation of frozen poultry meat

A microbiological screening method for the detection of irradiation of frozen poultry meat was developed on the basis of the combined use of total cell count by the direct epifluorescent filter technique (DEFT) and viable cell count by the aerobic plate count method (APC). Samples of ground, deboned poultry leg were irradiated or not with dose levels of 3, 5 and 7 kGy using an electron beam accelerator. All samples were frozen before the irradiation treatment. The average values of the differences between DEFT and APC counts in control samples and those irradiated with doses of 3, 5 and 7 kGy were 1.14 log units for control samples, and 3.16, 3.68 and 3.79 log units for the irradiated samples. A difference of at least 2 log units can therefore be considered as a limit value indicating probable irradiation treatment necessitating further investigations.

Practical issues in the clinical application of mismatch negativity

The mismatch negativity (MMN) recordings provide an objective measure of the preattentive, automatic auditory discrimination function. This article deals with issues central to the recording of the MMN and the interpretation of the results for clinical and electrodiagnostic purposes. The methods of acquiring as pure an MMN response as possible, i.e., one not contaminated by auditory cortical responses reflecting other functions, are discussed first. Second, other technical questions associated with the recording are reported on, e.g., what MMN parameters should be recorded and how, what is the smallest recordable MMN response, and what is the repeatability of the MMN recordings. Then, the effect of various physiological factors on the MMN (age, alertness, gender, topographic distribution of the MMN) is considered. The correlation between auditory discrimination performance and the MMN amplitude, observed in normal population, is dealt with. Finally, there is a short concluding overview on clinical findings of MMN recordings and discussion on their electrodiagnostic applications.

Disc degeneration of pediatric patients in lumbar MRI

Magnetic resonance imaging (MRI) is widely used in pediatric spinal disorders, but the prevalence of associated lumbar disc degeneration (DD) has not been evaluated previously. In this study we investigated whether children with suspected spinal disease had increased tendency to early DD. We analyzed lumbar MRI scans of 32 patients and 49 control subjects under 15 years old. Only four patients (13%) had DD on T2-weighted MRI and they were all over 10 years old. Eleven subjects (22%) in the control group had DD. It seems that disc degeneration is seldom found in patients under 10 years old.

Comparison of insulin regimens in patients with non-insulin-dependent diabetes mellitus

BACKGROUND

Insulin is widely used to improve metabolic control in patients with non-insulin-dependent diabetes mellitus (NIDDM), but there is no consensus about the optimal regimen of insulin treatment.

METHODS

We treated 153 patients with NIDDM for three months with five regimens: (1) oral hypoglycemic drug therapy plus NPH insulin given at 7 a.m. (the morning-NPH group), (2) oral hypoglycemic drug therapy plus NPH insulin given at 9 p.m. (the evening-NPH group), (3) NPH and regular insulin (ratio, 70 units to 30 units) given before breakfast and dinner (the two-insulin-injection group), (4) NPH insulin at 9 p.m. and regular insulin before meals (the multiple-insulin-injection group), and (5) continued oral hypoglycemic drug therapy (the control group).

RESULTS

The mean (+/- SE) value for glycosylated hemoglobin decreased similarly in all four insulin-treatment groups (1.7 +/- 0.3, 1.9 +/- 0.2, 1.8 +/- 0.3, and 1.6 +/- 0.3 percent, respectively). The decrease was significantly greater in these four groups than in the control group (0.5 +/- 0.2 percent; P < 0.001 vs. all insulin-treated groups). Weight gain was significantly less (1.2 +/- 0.5 kg) in the evening-NPH group than in the other insulin-treatment groups (2.2 +/- 0.5 kg in the morning-NPH group, 1.8 +/- 0.5 kg in the two-insulin-injection group, and 2.9 +/- 0.5 kg in the multiple-injection group; P < 0.05). In addition, the increment in the mean diurnal serum free insulin concentration was 50 to 65 percent smaller in the evening-NPH group than in the other insulin-treatment groups. Subjective well-being improved significantly more in the insulin-treatment groups than in the control group (P < 0.001).

CONCLUSIONS

In patients with NIDDM who are receiving oral hypoglycemic drug therapy, the addition of NPH insulin in the evening improves glycemic control in a manner similar to combination therapy with NPH insulin in the morning, a two-insulin-injection regimen, or a multiple-insulin-injection regimen, but induces less weight gain and hyperinsulinemia. The data thus suggest that patients with NIDDM do not benefit from multiple insulin injections and that nocturnal insulin administration appears preferable to daytime administration.

Septic Haemophilus influenzae polyarthritis demonstrated best with Tc-99m HMPAO labeled leukocytes

A 5-year-old girl with fever and tenderness in her left wrist and right ankle was hospitalized. Bone scanning and Tc-99m labeled leukocyte imaging showed increased uptake in these joints and also in her left knee. These radionuclide methods helped determine the diagnosis and were superior to plain radiography and CT scanning. Uptake was greater on leukocyte imaging than it was on the bone scan. The patient had infectious polyarthritis caused by Haemophilus influenzae, which is a very rare cause of acute polyarthritis in children older than 2 years. The patient fully recovered with antibiotic therapy, and no surgical procedure was needed.

Clinical comparison of 99Tcm-HMPAO labelled leucocytes and 99Tcm-nanocolloid in the detection of inflammation

Forty-five patients with various inflammatory diseases were imaged with 99Tcm-HMPAO labelled leucocytes and 99Tcm-nanocolloid within 7 days. The overall sensitivity of 99Tcm-leucocytes was 97% and that of 99Tcm-nanocolloid 59% and both agents had a 100% specificity. The 99Tcm-leucocyte method showed reliable results in various inflammatory and infectious conditions, and seems suitable as a primary imaging method. On the contrary, 99Tcm-nanocolloid cannot be recommended for use in inflammatory bowel diseases, soft tissue abscesses or prosthetic vascular graft infections. However, 99Tcm-nanocolloid gave reliable information in inflammatory and infectious bone and joint diseases in which it had a 90% sensitivity and 100% specificity. In those lesions the 99Tcm-nanocolloid method may be useful, because it is simple, fast and cheap. Yet, further evaluation is needed.

The efficacy of adhesives in the application of wound dressings

The use of adhesive preparations to reinforce surgical tapes and to secure dressings to the skin is standard practice. BioBrane is a biosynthetic membrane for use in dressing clean, well-debrided wounds, particularly partial-thickness burns and skin graft donor sites. The close and undisturbed contact of this material with the wound surface is important during the first 2 days after its application to achieve adherence. This has prompted a study to test the relative anchoring strength of four methods of securing the dressing to the normal skin around the wound: 1/2-inch (1.27-cm) Steri-Strips only; Mastisol, a mastic compound, with and without 1/2-inch Steri-Strips; and compound tincture of benzoin, USP, in combination with 1/2-inch Steri-Strips. The results obtained with a tension of 1.1 pounds/square inch (0.5 kg/6.5 cm2) were not conclusive as to the superiority of any one method. However, with a tension of 2.2 pounds/square inch (1 kg/6.5 cm2), the combination of mastic compound and 1/2-inch Steri-Strips provided the strongest adhesion. This type of application should also prove useful when other types of surgical dressings must be anchored in place.

Reinforcement of surgical adhesive strips

Surgical adhesive strips are often used for closure of some wounds or to minimize tension on sutures after closures. The package insert of the type most commonly used (Steri-Strip), indicates that the application of compound tincture of benzoin, U.S.P. (CTB) increases strip adhesion. The increase in adhesive power by CTB was compared with a preparation containing gum mastic (Mastisol). The study clearly demonstrated that the latter preparation provided a markedly more adhesive strength than that obtained with CTB.