The Diagnostic Usefulness of Electron Microscopy Investigation of Orbital Embryonal Rhabdomyosarcomas

The ultrastructural study of three malignant orbital tumors, only one of which was correctly diagnosed as embryonal rhabdomyosarcoma upon histologic examination, is reported. In all 3 cases electron microscopic investigation revealed the presence of rhabdomyoblasts. These were easily recognizable in one case in which the diagnosis was made on the basis of the optical microscopic study. The other two cases needed further tests to evince rhabdomyoblasts. The importance of an ultrastructural study for a histogenetic characterization of this kind of tumor is emphasized. As far as embryonal rhabdomyosarcomas are concerned, the electron microscopic study is possible, and it gives useful results even when material fixed with routine histologic methods (formalin, Bouin's solution) are used.

Evaluation of the Italian cytological subclassification of thyroid indeterminate nodules into TIR-3A and TIR-3B: a retrospective study of 290 cases with histological correlation from a single institution

PURPOSE

The Italian consensus to classify thyroid cytology has provided a standardized reporting scheme, including the subdivision of indeterminate for malignancy TIR-3 category into TIR-3A (low-risk) and TIR-3B (high-risk). We aimed to present our experience on this subclassification by evaluating risks of malignancy and the validity in sorting nodules with dissimilar risks. Another aim was to compare our performance against the Bethesda system.

METHODS

Fine-needle aspirates of 290 TIR-3 that underwent thyroid surgery at our hospital (2008-2013) were reviewed and divided into TIR-3A or TIR-3B, and AUS/FLUS or FN/SFN. Cytological diagnoses were then correlated to histology. Results were evaluated using univariate analysis.

RESULTS

The subclassification into TIR-3A and TIR-3B differentiated hyperplastic nodules (p = 0.000) but not adenomas (p = 0.090). Rates of malignancy were significantly different between TIR-3A (10.2%) and TIR-3B (43.8%); TIR-3B malignancies were often papillary carcinomas (83%). TIR-3A/TIR-3B accounted for high sensitivity (84.5%; CI 79.7-88.4%), accuracy (64.1%; CI 58.6-69.6%) and NPV (89.8%; CI 85.6-93.0%) as opposed to modest specificity (55.8%; CI 49.9-61.6%) and PPV (43.8%; CI 38.1-49.8%). The rate of malignancy in AUS-FLUS was higher than in TIR-3A (p = 0.007), whereas it was not different between FN/SFN and TIR-3B (p = 0.337). Sensitivity of the Bethesda system was significantly lower respect to the Italian system.

CONCLUSIONS

The study supports the Italian consensus showing a different risk of malignancy for TIR-3A as compared to TIR-3B. TIR-3A/TIR-3B subclassification is valid to sort out benign nodules (high NPV) and malignancies (high sensitivity) but not adenomas (modest specificity, low PPV). In our experience, sensitivity is the main difference between Italian and Bethesda systems.

Malignant Mesothelioma in Rome, Italy 1980-1995. A Retrospective Study of 79 Patients

Aim and background

To evaluate the characteristics of a case-series of 79 malignant mesothelioma patients collected from the main teaching hospital of Rome, Italy, and other local clinics of Latium Region and to assess the role of asbestos exposure, since previous studies on the occurrence of the disease in this area were lacking.

Methods

The study included cytohistologically diagnosed malignant mesothelioma (71 pleural, 7 peritoneal, and 1 testicular tunica vaginalis) detected or referred for consultation during the period 1980-1995. Information regarding occupational and/or nonoccupational exposures was derived from clinical records and interviews, when available.

Results

Patients were resident in Rome and other towns of Latium; a few were from other parts of central and southern Italy. Exposure to asbestos was assessed for 45.5% of patients, another 45.5% had unknown exposure, and for the remaining 9% such information was lacking. Occupational exposure occurred in 53% of men for whom information was available and nonoccupational exposure occurred in 20% of women. The study identified two clusters of cases from an asbestos-cement plant and a facility where asbestos was ubiquitous. Furthermore, most exposed subjects reported occupations in the construction industry, which is particularly active in the Latium Region; others were railroad workers, naval mechanics and navy personnel, bakers, explosive workers and car mechanics. A few patients reported indoor exposure to asbestos at home and/or in the workplace.

Conclusions

The study confirmed that mesothelioma risk is present in several job titles of the construction industry, and it is no longer confined to workers employed in the manufacture or application of asbestos products. The occurrence of malignant mesothelioma in patients with unexpected occupational and nonoccupational exposures indicates the need for further investigation on previously underestimated exposures.

The mitochondrial genome of the antarctic springtail Folsomotoma octooculata (Hexapoda; Collembola), and an update on the phylogeny of collembolan lineages based on mitogenomic data

This study provides the description of the complete mitochondrial genome of the Antarctic collembola Folsomotoma octooculata. Since mitogenomic data are extensively used for phylogenetic reconstruction, we also provide a phylogenetic reconstruction of the internal relationships of some collembola taxa using the complete mitochondrial DNA data available at present for this group. The complete mitochondrial genome sequence of F. octooculata has been obtained using standard amplification and sequencing methods for long DNA templates. Sequence data are analyzed using bayesian methods based on the analysis of nucleotide and amino acid sequences. The complete set of available mitochondrial DNA sequences for ten species of the group is also analyzed for the presence of lineage-specific gene order of the 37 encoded genes. The results of the phylogenetic analysis are compared with previous morphological and molecular analyses, showing some intriguing outcomes, such as the paraphyly of Entomobryomorpha, the derived position of Podura aquatica within Poduromorpha, and the sister group relationships between the single Symphypleona species available for comparison and the entomobryid Orchesella villosa. The F. octooculata mitochondrial genome generally conforms with those observed in other basal hexapod species and displays the plesiomorphic gene order observed for Pancrustacea. Mitogenomic data are useful to reconstruct a molecular phylogeny of major collembolan taxa. In spite of the limited number of species for which entire mitochondrial genomes are known, the coverage of many of the major lineages allows some preliminary conclusions concerning the relationships among families and suborders.

Spike-timing dependent plasticity in a transistor-selected resistive switching memory

In a neural network, neuron computation is achieved through the summation of input signals fed by synaptic connections. The synaptic activity (weight) is dictated by the synchronous firing of neurons, inducing potentiation/depression of the synaptic connection. This learning function can be supported by the resistive switching memory (RRAM), which changes its resistance depending on the amplitude, the pulse width and the bias polarity of the applied signal. This work shows a new synapse circuit comprising a MOS transistor as a selector and a RRAM as a variable resistance, displaying spike-timing dependent plasticity (STDP) similar to the one originally experienced in biological neural networks. We demonstrate long-term potentiation and long-term depression by simulations with an analytical model of resistive switching. Finally, the experimental demonstration of the new STDP scheme is presented.

Diagnostic utility of thyroglobulin measurement in the fine needle aspirates from cervical lymph nodes: a case report

Fine needle aspiration cytology (FNAC) is the more accurate diagnostic method for cervical lymph node (CLN) metastasis from differentiated thyroid cancers (DTC). However, FNAC diagnosis of cystic CLN is, in most cases, uninformative due to inadequate cellularity. Recently, thyroglobulin (Tg) detection in FNAC needle washout fluid has been shown to improve the diagnostic accuracy of FNAC, and its routine association with cytology is recommended. We here describe the case of a 20 yr old girl complaining of the recent appearance of palpable non-painful laterocervical nodes in the neck. Ultrasound examination revealed the presence of 3 cystic CLNs and 2 mixed thyroid nodules, with the larger one showing irregular margins. On the latter, and on 2 larger CLNs, FNAC was performed, and both Tg protein and mRNA were determined in the needle washout. The cytological analysis was not diagnostic for the two CLNs, while that of the thyroid nodule reported the presence of colloid and groups of thyrocytes with normal morphology. Both CLNs showed, however, high levels of Tg protein and were positive for Tg mRNA, suggestive of metastatic DTC. Based on these findings, the FNAC analysis was performed on the second smaller thyroid nodule suggesting (Tir4) the presence of PTC. The patient was then subjected to total thyroidectomy with lymph nodes resection of the central and homolateral compartments. The histological diagnosis confirmed the presence of a PTC in the small nodule and metastatic lymph nodes. In conclusion, this case confirms that the cytological diagnosis of cystic lymph nodes is challenging, and that the measurement of Tg protein and/or mRNA in the needle washout may overcome this limitation.

Surgical strategies in patients with medullary thyroid carcinoma

OBJECTIVES

Aim of the study was to identify, in 59 operated patients affected by medullary thyroid carcinoma (MTC), the recurrence rate, survival, mortality and incidences of surgically derived hypoparathyroidism and recurrent laryngeal nerve injury (RLNI).

MATERIALS AND METHODS

Based on pre-surgical diagnosis of the 59 patients included in the study, 35 underwent total thyroidectomy with central neck dissection (Group A), 14 total thyroidectomy, central neck dissection and monolateral functional neck dissection (Group B) and 10 total thyroidectomy central neck dissection, bilateral functional neck dissection (Group C). Overall survival, recurrences, incidence of hypoparathyroidism and RLNI were evaluated.

RESULTS

The survival and recurrences were not statistically different among the three Groups. In Group B there was major probability of re-operation (p=0.042). The mortality rate was clearly major in Group C (p=0.003) due to the stage of pathology. Group C showed a high number of hypoparatiroidism compared to Group B, and B compared to A. In Group A there was only one unexpected RLNI; in 5 cases, 3 in Group B and 2 in Group C, there were a necessity laringeal section due to nerve tumor involvement.

CONCLUSIONS

From our data it appears clearly that disease outcome following the different surgical approaches is mainly determinated by the stage of the disease at diagnosis. However, the finding that patients in Group A and B showed a high rate of local-regional recurrences may suggest that homolateral lymphadenectomy in Group A patients and bilateral lymphadenectomy in Group B patients should be always performed.

Physical models of size-dependent nanofilament formation and rupture in NiO resistive switching memories

NiO films display unipolar resistance switching characteristics, due to the electrically induced formation and rupture of nanofilaments. While the applicative interest for possible use in highly dense resistance switching memory (RRAM) is extremely high, switching phenomena pose strong fundamental challenges in understanding the physical mechanisms and models. This work addresses the set and reset mechanisms for the formation and rupture of nanofilaments in NiO RRAM devices. Reset is described in terms of thermally-accelerated diffusion and oxidation processes, and its resistance dependence is explained by size-dependent Joule heating and oxidation. The filament is described as a region with locally-enhanced doping, resulting in an insulator-metal transition driven by structural and chemical defects. The set mechanism is explained by a threshold switching effect, triggering chemical reduction and a consequent local increase of metallic doping. The possible use of the observed resistance-dependent reset and set parameters to improve the memory array operation and variability is finally discussed.

[Oral-motor skills assessment scales and feeding and swallowing measurements in the paediatric age: a review of literature]

This study aims to present an overview of feeding and oral-motor assessment scales currently available for the paediatric age group through a review of literature from 1980 to 2009.

Phenotypic changes of the thyrocyte membrane in papillary thyroid carcinoma. A three-dimensional study

Aim of the study was to assess the presence of structural changes in the complex carbohydrate chains of thyroid epithelia undergoing neoplastic transformation. We investigated thyroid cells from neoplastic lesions using a panel of lectins with specific affinity for distinct carbohydrate residues. Sixty samples of thyroid tissue, including normal, hyperplastic and neoplastic lesions were obtained from surgical specimens and blindly evaluated with lectin stains. Confocal microscopy was used to obtain three-dimensional (3-D) images of the samples with a positive reaction. Wheat germ agglutinin (WGA) was consistently positive on the apical membrane of papillary thyroid carcinomas (PTC), was weakly expressed in follicular carcinomas (FC) and resulted negative in normal thyrocytes and in benign conditions. The 3-D microscopy model showed that the WGA staining pattern in light microscopy corresponds to a continuous layer on the luminal surface of both papillary and tubular structures of PTC cells. The other lectins under evaluation did not provide any significant result. In conclusion, in PTC the apical border of thyrocytes showed a strong, specific and consistent staining with WGA. These findings may be related to a modified interaction of thyroglobulin molecule with thyroid cell membrane and with the expression of molecules that are involved in the process of tumorigenesis and tumor progression.

DNA-based discrimination and frequency of phytoplasma infection in the two hawthorn-feeding species, Cacopsylla melanoneura and Cacopsylla affinis, in northwestern Italy

A molecular tool, focused on the mitochondrial Control Region (CR), was developed to discriminate the two hawthorn-feeding psyllid species, Cacopsylla melanoneura (Förster) and C. affinis (Löw), and to estimate their frequencies in mixed populations. The test was carried out in paired and single-tube amplifications and validated analysing 52 male specimens previously determined by morphological analysis. The frequencies of the two species in mixed populations in the Aosta Valley (northwestern Italy) were analysed. The presence and type of 16SrX-group phytoplasmas was detected by nested PCR and RFLP tests in both species. C. melanoneura was the predominant species (86.5%; 80.4-91.2 CI); of these, 0.9% of the samples were positive for 'Ca. Phytoplasma mali' and 1.8% for 'Ca. Phytoplasma pyri'. One of 21 specimens of C. affinis was positive for 'Ca. Phytoplasma pyri'. The test also allowed us to identify two genetic variants of C. melanoneura, depending on the presence or absence of a 56 bp indel; these were named WI (with indel) and WOI (without indel), respectively. Further analyses were carried out on C. melanoneura specimens collected in apple orchards at six different locations in northern Italy where different levels of transmission efficiency have been described. Our preliminary observations suggest that some differences might exist between the two genetic variants in their ability to transmit phytoplasmas and to colonise different host plants.

Acetylcholinesterase genes in the basal Hexapod Orchesella villosa

Acetylcholinesterase (AChE) is a key enzyme of the cholinergic nerve system. Of the two forms found in insects, the predominant one is active in the synapses and is the target of organophosphate and carbamate insecticides, while the role of the second is currently unknown. Two acetylcholinesterase cDNAs from the basal hexapod Orchesella villosa have been characterized and compared with others reported form insects. One form conforms well to the typical structure, while the other is characterized by an unusual 3' region. No amino acid mutation could be directly associated with known resistance mutations in other insect species or to a clear signal of selection in the distribution of alleles, although the action of some population process is suggested.

The complete nucleotide sequence of the mitochondrial genome of the oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae)

The complete mitochondrial genome of the oriental fruit fly Bactrocera dorsalis s.s. has been sequenced, and is here described and compared with the homologous sequences of Bactrocera oleae and Ceratitis capitata. The genome is a circular molecule of 15,915 bp, and encodes the set of 37 genes generally found in animal mitochondrial genomes. The structure and organization of the molecule is typical and similar to the two closely related species B. oleae and C. capitata, although it presents an interesting case of putative intra-molecular recombination. The relevance of the growing comparative dataset of tephritid complete mitochondrial genomes is discussed in relation to the possibility to develop robust assays for species discrimination in quarantine and agricultural monitoring practices, as well as basic phylogeography/population genetic studies.

The mitochondrial genomes of Campodea fragilis and Campodea lubbocki (Hexapoda: Diplura): High genetic divergence in a morphologically uniform taxon

Complete mitochondrial genome sequences are presented from two dipluran hexapods (i.e., a group of "primarily wingless insects") of the genus Campodea and compared to those of other arthropods. Their gene order is the same as in most other hexapods and crustaceans. Structural changes have occurred in tRNA-C, tRNA-R, tRNA-S1 and tRNA-S2 as well as in both ribosomal RNAs. These mtDNAs have striking biases in nucleotide and amino acid composition. Although the two Campodea species are morphologically highly similar, their genetic divergence is larger than expected, suggesting a long evolutionary history, perhaps under stable ecological conditions.

Beta-lactamase inhibition with clavulanic acid supplementing standard amoxycillin-based triple therapy does not increase Helicobacter pylori eradication rate

BACKGROUND

Antibiotic resistance is the main reason of failure for H. pylori eradication and beta-lactamases produced by resistant H. pylori strains is a possible mechanism underlying ineffectiveness of an amoxycillin-based triple therapy.

AIM

To investigate the benefit of using clavulanic acid associated with amoxycillin compared with amoxycillin alone in a standard triple therapy.

METHODS

A total 172 H. pylori-positive dyspeptic patients were randomised to a daily treatment with esomeprazole (20 mg bid), clarithromycin (500 mg bid) and either amoxycillin plus clavulanic acid (1 g bid) or amoxycillin (1 g bid) alone for 1 week. H. pylori status was defined by histology and urea breath test at entry and following 8 weeks from the end of therapy by urea breath test and antigen faecal assessment.

RESULTS

At intention-to-treat and per-protocol analysis eradication rates achieved by amoxycillin plus clavulanic acid (72 and 78%) were higher, but not significantly, than those achieved by amoxycillin alone triple therapy (62 and 72%). Compliance was good, side-effects mild and with a similar incidence in both regimens.

CONCLUSIONS

Clavulanic acid supplemented to amoxycillin-based standard triple therapy does not significantly increase the H. pylori eradication rate with standard triple therapy.

One-week once-daily triple therapy with esomeprazole, levofloxacin and azithromycin compared to a standard therapy for Helicobacter pylori eradication

BACKGROUND

Primary antibiotic-resistance and poor compliance are the main causes of Helicobacter pylori eradication failure of standard regimens.

AIM

To investigate eradication rate, patient compliance and tolerability of a 1-week once-daily levofloxacin plus azithromycin triple therapy versus the standard twice-daily triple therapy.

PATIENTS AND METHODS

A total of 164 H. pylori-positive patients were randomised to either esomeprazole 20mg, levofloxacin 500 mg and azithromycin 500 mg once-daily (ELAz) or esomeprazole 20mg, clarithromycin 500 mg and amoxycillin 1g twice-daily (ECA) for 1 week. H. pylori infection was defined at entry by histology and urea breath test; cure of infection was determined both by negative urea breath test and H. pylori stool antigens.

RESULTS

H. pylori eradication rates of ELAz and ECA were similar at intention-to-treat (both 65%) and per-protocol analyses (70% versus 76%, respectively). Incidence of poor compliance was lower, although not significantly, in patients randomised to ELAz than to ECA (4% versus 10%); tolerability was significantly higher for ELAz than for ECA (88% versus 70%; P=0.01).

CONCLUSIONS

Once-daily levofloxacin plus azithromycin-based triple therapy achieves an H. pylori eradication rate comparable to that of standard twice-daily triple therapy, but is associated with higher patient compliance and might even be better tolerated.

Secondary structure, high variability and conserved motifs for domain III of 12S rRNA in the Arthropleona (Hexapoda; Collembola)

The robustness of different hypothetical structural models for ribosomal RNAs can be established by comparing sequences from widely different taxonomic groups. Secondary structure models of the two mitochondrial ribosomal subunits have been proposed for a large number of pterygote insects, but little information is available for the more ancient entognath hexapods. We have investigated the most frequently sequenced of the four domains of the mitochondrial small subunit rRNA in twenty-two collembolan species in the taxon Arthropleona. We provide secondary structure models of this third domain for representative species, and a consensus based on all species studied. This consensus is in partial agreement with previous models. High levels of variation, in terms of length and of primary sequence, are present in the peripheral portions of the domain. Some of the structural elements differ more among genera of springtails than among insect orders. Conversely, a limited number of structural differences compared with other taxa have been detected in the core regions.

Increased thrombin generation and circulating levels of tumour necrosis factor-alpha in patients with chronic Helicobacter pylori-positive gastritis

BACKGROUND

Conflicting data have been reported concerning the relationship between Helicobacter pylori infection and coronary heart disease.

AIM

To evaluate clotting system activation and plasma levels of tumour necrosis factor-alpha, a procoagulant cytokine, in patients with H. pylori-positive and -negative gastritis.

METHODS

Three groups of patients were identified: 38 with H. pylori-positive gastritis, 18 with H. pylori-negative gastritis, and 40 H. pylori-negative controls with normal gastric mucosa. Plasma levels of prothrombin fragment 1 + 2 (F1 + 2) and tumour necrosis factor-alpha were assayed. Patients were also controlled after 2 and 6 months following standard H. pylori eradication treatment.

RESULTS

At baseline, fragment 1 + 2 and tumour necrosis factor-alpha levels in H. pylori-positive patients were significantly higher than those in H. pylori-negative patients with gastritis (P < 0.05 and P < 0.01, respectively). After H. pylori eradication, fragment 1 + 2 and tumour necrosis factor-alpha levels showed a significant decrease at 2 months (P = 0.03 and P = 0.02, respectively) and a further reduction at 6 months, reaching levels observed in H. pylori-negative patients and controls.

CONCLUSIONS

The increase thrombin generation rate and the correlation of plasma fragment 1 + 2 and tumour necrosis factor-alpha levels in H. pylori-positive patients suggest a role for inflammation in mediating the relationship between H. pylori infection and activation of the clotting system.

Sperm structure and spermiogenesis in Coletinia sp. (Nicoletiidae, Zygentoma, Insecta) with a comparative analysis of sperm structure in Zygentoma

The spermatozoon of Coletinia sp. has a bilayered acrosome, a short nucleus (4 microm) and a relatively short sperm tail with two mitochondrial derivatives. The chromatin is uniformly dense except for several electron-lucid channels or strands which permeate the nucleus and which originate in the spermatid as invaginations of the nuclear envelope. The invaginations occur mostly or exclusively along two meridians of the spermatid that are also characterized by the presence of a longitudinal rod of medium electron density. The two rods (designated as 'mid-spermatid rods') evidently are instrumental in the formation of the electron-lucid channels. The significance of this elaborate system of intranuclear channels is not understood. The sperm tail has a 9 + 9 + 2 axoneme with each of the nine microtubular doublets accompanied by an accessory microtubule; scant intertubular material can also be distinguished. Hence, the tail axoneme resembles that of many pterygote insects. Each of the two mitochondrial derivatives contains a crystalline inclusion that has periodically spaced layers going in different directions on either side of the midline. Two synapomorphic traits appear to be shared by Ateluridae and Nicoletiidae, namely the invaginations of the nuclear membrane along two meridians of the nucleus and the shape of the crystalline inclusions of the mitochondrial derivatives. Four species from the family Lepismatidae were also examined as to their sperm ultrastructure. Three of them, Allacrotelsa kraepelini, Ctenolepisma longicaudata and Ctenolepisma sp., were found to be very similar to the two previously examined lepismatids, Thermobia domestica and Lepisma saccharina. On the other hand, spermatozoa of Tricholepisma aurea were aggregated in small groups rather than pairwise joined as seen in the other lepismatids. Sperm characters are also used to reconstruct a phylogenetic hypothesis which suggests a close relationship between Ateluridae and Nicoletiidae.

[Common bile duct stones: the surgical treatment is always valid]

AIM

The treatment of common bile duct stones has changed with the new therapeutic techniques, that have replaced the conventional therapy, represented by surgery. Anyway, they could cause some problems, that must be regarded. Therefore, we wish to confirm the importance of the conventional surgery in the management of patients with common bile duct stones.

METHODS

A total of 147 patients were operated for common bile duct stones (73 in emergency and 74 in election). The intraoperative cholangiography was carried out in 141 patients and a choledocoscopy in 130 patients. A drain of Kehr was positioned in 120 patients, a bilio-digestive anastomosis in 26 cases and in 1 case there was a direct suture of the common bile duct without drain. All patients were treated with a short-term antibioticotherapy, protracted to 5 days in the emergency cases. In the patients with the drain of Kehr there was a control cholangiography after 7 days from operation and it was removed after 25 days. The analysis of the results was done dividing the patients according to the age: <75 years old and >75 years old.

RESULTS

Nobody died during the operation. Complications were 17.4% in the patients >75 years old and 2,6% in the patients <75 years old. There were 2 death, in the postoperative period, for the group >75 years old. Cases operated in emergency were 68.1% of "old" patients and 37.2% of "young" patients. The postoperative period was 14.9+/-9.2 days for the "old" group and 10.9+/-5.2 days for the "young" group.

CONCLUSIONS

The treatment of common bile duct stones is still a surgical treatment, particularly for "old" patients.

Actinomycosis of submandibular gland: an unusual presentation

An unusual presentation of oro-facial actinomycosis, mimicking the clinical appearance of a malignant lesion is reported. The patient, a 74-year-old female, presented with a right submandibular mass, which slowly grew in size over a period of about 2 months, and a modest dysphagia. A painless cervical mass was palpable over the submandibular region. The rhino-pharyngo-laryngeal region, explored by flexible fiberoptic examination, was normal. At ultrasonography, a 2x2 cm infiltrating dyshomogeneous mass, involving the right submandibular gland, was visible. No connection with adjacent organs was found. There was no associated cervical lymphoadenopathy. Ultrasound-guided fine-needle aspiration cytology, performed on lesion, revealed no evidence of malignancy. The presence of characteristic colonies of actinomyces infection was found. The patient was treated initially with tetracycline chloridrate 100 mg: 1 tablet every 12 hours for 7 weeks, but a repeat ultrasonography showed no resolution. A further fine-needle aspiration cytology showed no actinomyces infection in the specimen. The patient was treated with methylprednisolone, 20 mg every 24 hours, for 5 days. After steroid treatment, the patient has been well and, upon repeat ultrasonography, total resolution of the submandibular lesion was confirmed. In conclusion, the clinical presentation of cervicofacial actinomycosis is variable and may mimic a malignant lesion or chronic granulomatous infections. Diagnostic and therapeutic findings are discussed.

The mitochondrial genome of the olive fly Bactrocera oleae: two haplotypes from distant geographical locations

The complete sequence of the olive fly (Bactrocera oleae) mitochondrial genome has been determined. Two independent haplotypes, from flies of distant geographical origin (Italy and Portugal) were completely sequenced. The molecule is 15815 bp long, and shows the gene content and organization typical of insects, namely thirteen protein coding genes (PCGs) encoding proteins involved in oxidative phosphorylation, two rRNAs, twenty-two tRNAs and a long (949 bp) noncoding region. The genomes of the two fly specimens share the same arrangement, differing by a mere thirty-one point mutations. The differences are mostly transitions (26) and synonymous substitutions in PCGs (21). The two new sequences are compared with others already present in the database.

Localization and expression of thyroid hormone receptors normal and neoplastic human thyroid

The aim of this study was to investigate the regional expression of thyroid hormone nuclear receptor forms (TR(alpha) and TR(beta)) and isoform (TR(alpha1) and TR(beta2)) mRNAs in normal and neoplastic (benignant and malignant) human thyroid tissue. Tumor specimens from patients with thyroid carcinomas (papillary: 5 cases; follicular: 5 cases; anaplastic: 2 cases), thyroid follicular adenomas (7 cases) and tissue from normal thyroid glands (12 cases) were analyzed by in situ hybridization and semiquantitative RT-PCR for the expression of TR(alpha1) and beta, as well as for the isoform alpha2 that does not bind the hormone. In normal tissues, TR(alpha2) was expressed at lower levels compared to TR(alpha1) (alpha1/alpha2 = 4.3). In papillary and follicular carcinomas, the expression of TR(alpha1) and TR(beta) did not change as compared with normal thyroid tissue and adenomas (0.87 +/- 0.15 SD vs 0.89 +/- 0.17 densitometric units, DU, and 0.15 +/- 0.02 vs 0.14 +/- 0.03 DU, respectively). However, the expression of TR(alpha2) was significantly higher in differentiated carcinomas compared to normal thyroid tissue and adenomas (0.47 +/- 0.05 vs 0.20 +/- 0.05 DU, p < 0.05) with alpha1/alpha2 = 1.4. In anaplastic carcinoma all TRs were absent. We concluded that both normal and pathological thyroid tissues, with the exception of anaplastic carcinoma, express all TRs in thyreocites and that differentiated thyroid carcinomas are associated in enhancing the expression of TR(alpha2) mRNA.

A one-generation cluster of malignant mesothelioma within a family reveals exposure to asbestos-contaminated jute bags in Naples, Italy

Substantial evidence supports the role of asbestos in malignant mesothelioma. Clustering for this malignancy among relatives not only suggests genetic susceptibility as a relevant component but also provides a clue to investigate non-occupational sources of exposure. We identified five cases of malignant mesothelioma within one family with exposure to asbestos experienced during childhood, as 'next door' residents of a workshop recycling asbestos-contaminated jute sacks in Naples, Italy. This cluster discloses the health risk in the reuse of bags that previously had contained asbestos. Furthermore, it emphasizes the role of asbestos in the genetic-environmental interaction issue of malignant mesothelioma.

Sperm ultrastructure and spermiogenesis in the relic species Tricholepidion gertschi Wygodzinsky (Insecta, Zygentoma)

The silverfish Tricholepidion gertschi is of interest in that it is the most basal representative of Zygentoma. An ultrastructural study of its spermiogenesis was performed to find out whether there are traits which resemble those of other, more advanced insects. This was found to be the case; spermiogenesis can be considered to be of a common insectan type, leading to the formation of elongated sperm cells with acrosome, nucleus, neck region and a tail with axoneme and two mitochondrial derivatives. Total cell length, 50 microm, is short for an insect. There are some specializations, which probably represent autapomorphies. The acrosome has a posterior canal or cleft that makes a U-turn. The centriole adjunct forms a prominent post-nuclear ring surrounding the centriole and have a posterior extension, and further originates nine intertubular fibers with a longitudinal periodicity and two accessory bodies. The mitochondrial derivatives have five rows of regularly spaced cristae within a crystalline matrix. The axoneme has accessory tubules consisting of 16 protofilaments, formed at the B-tubules of the doublets and placed at some distance from them in the posterior part of the sperm tail.

Binucleate and biflagellate spermatozoa in Tricholepidion gertschi Wygodzynsky (Insecta, Zygentoma)

The phenomenon of sperm pairing is known from some species of the apterygotan insect order Zygentoma, and has been described as the close apposition of two sperm cells. When released from the testes, they are single cells; pairing taking place in the deferent ducts. In a study of the relic species Tricholepidion gertschi, Zygentoma, sperm pairing was found to be due to a true fusion of two partners along their entire sperm head regions. The spermatozoon thus formed has two acrosomes, two nuclei and two separate sperm tails. The biflagellate spermatozoon swims with coordinated movements of its two flagella only when the two flagella lie close together but is totally uncoordinated when separate. The spermatozoon is about 50 microm long, thus much shorter than those of related apterygotan species. The mechanism of sperm cell fusion is unclear, although it appears that a 55-nm wide layer of electron dense substance, here termed the peripheral lamina, may play a role in delimiting the extent of sperm fusion.

Malignant pleural mesothelioma in bakers and pastry cooks

BACKGROUND

The occurrence of malignant pleural mesothelioma (MPM) among bakers and pastry cooks has never been documented.

CASE REPORTS

We detected eight cases of MPM in bakers, pastry cooks, and biscuit cooks engaged in making, baking/cooking, and selling pastry/bread in two hospital-based series (Rome and Orbassano/Turin, Italy; period 1990-1997; 222 cases). Field-investigations revealed asbestos-containing material (ACM) in ovens for baking bread, that were manufactured prior to the 1980s.

CONCLUSIONS

It is suggested that there is a possible new association of the risk of having worked as a baker or pastry cook and MPM. Presumptive source of exposure to asbestos was the use of asbestos-insulated ovens.

The complete mitochondrial DNA sequence of the basal hexapod Tetrodontophora bielanensis: evidence for heteroplasmy and tRNA translocations

We present the complete 15,455-nt mitochondrial DNA sequence of the springtail Tetrodontophora bielanensis (Arthropoda, Hexapoda, Collembola). The gene content is typical of most metazoans, with 13 protein-coding genes (PCGs), 2 genes encoding for ribosomal RNA subunits, and 22 tRNA genes. The nucleotide sequence shows the well-known A+T bias typical of insect mtDNA; its A+T content is lower (72.7%) than that observed in other insect species, but still higher than that in other arthropodan taxa. The bias appears to be uniform across the whole molecule, unlike other insect taxa, which show increased A+T content in the so-called A+T-rich region. However, the bias is slightly higher in the third codon positions of the PCGs (81.4%). Anomalous initiation codons have been observed in the nad2 and the cox1 genes. In the latter, the ATTTAA hexanucleotide is suggested to be involved in the initiation signaling. All tRNAs could be folded into the typical cloverleaf secondary structure, but the tRNA for cysteine appears to be missing the DHU arm. Long tandemly repeated regions (193 nt) were found in the A+T-rich region, which in turn was shown to have the possibility of forming a complex array of secondary structures. One of these structures encompassed the junction between the repeats. The A+T-rich region was also interesting in that it showed heteroplasmy in the number of repeats. Three haplotypes were found, possessing 2, 3, and 4 identical repeats, respectively. The order of protein coding and rRNA genes in the molecule was determined and was identical to that of all insects studied so far. However, two tRNA translocations were found which were unprecedented among Arthropoda. These involved the trnQ, which was found between the rrnS and the A+T-rich region, and the trnS(ucn), which was located between trnM and trnI. A preliminary phylogenetic analysis based on the amino acid sequence of the PCGs failed to find support for the monophyly of Hexapoda.

Discrepancy between polymerase chain reaction assay and Western blot analysis in the assessment of CagA status in dyspeptic patients

BACKGROUND

Infection with CagA-positive Helicobacter pylori may be diagnosed by detecting cagA gene by polymerase chain reaction assay (PCR) or serum antibodies against CagA by Western blot analysis. The aim of this study is to evaluate whether results of PCR and Western blot analysis are in agreement in CagA status assessment.

PATIENTS AND METHODS

Thirty-six dyspeptic patients with unknown H. pylori status underwent upper gastrointestinal endoscopy to assess the presence of mucosal lesions and to collect six gastric biopsies (three from the antrum and three from the body) for evaluation of H. pylori infection (rapid urease test, histology and PCR for ureA gene) and gastritis. CagA status was assessed by PCR (cagA gene) on two biopsy specimens and by Western blot analysis of serum (CagA-antibodies) in each patient.

RESULTS

At endoscopy, nine patients showed normal mucosa, 15 a duodenal ulcer and 12 antral erosions. Twenty-eight patients were found to be H. pylori-positive and eight H. pylori-negative. Of the 28 H. pylori-positive patients, 17 were CagA-positive and five were CagA-negative by both methods, five were CagA-positive by Western blot analysis but not by PCR and one was CagA-positive by PCR but not by Western blot analysis. Of the eight H. pylori-negative patients, none was CagA-positive by PCR, while six were CagA-positive by Western blot analysis. Therefore, the two tests agreed in only 24 patients (67%). In those patients in whom the PCR and Western blot analysis were not in agreement, the histological features appear to suggest that the results of the Western blot analysis should be considered false positives or false negatives.

CONCLUSIONS

PCR and Western blot analysis failed to provide comparable data in many cases. Western blot analysis seems to be more likely to give misleading results than PCR. Thus, PCR seems to be the method of choice to assess CagA status.

Application of an immunodiagnostic method for improving preoperative diagnosis of nodular thyroid lesions

BACKGROUND

Thyroid cancer is the most common endocrine malignant disease, but preoperative diagnosis remains a challenge. Fine-needle aspiration cytology has greatly improved the clinical management of thyroid nodules, but the preoperative characterisation of follicular lesions is very difficult. Many patients are thus referred to surgery more for diagnosis than for therapeutic necessity. We undertook an international multicentre study to assess the usefulness of immunohistocytochemical staining for two potential markers of malignant thyrocytes.

METHODS

Expression of galectin-3 and CD44v6 was tested on 1009 thyroid lesions (tissue specimens and cytological cell-blocks) and 226 fresh cytological samples obtained preoperatively by ultrasound-guided fine-needle aspiration of thyroid nodules (prospective analysis). The test used monoclonal antibodies specific for CD44v6 and galectin-3, the indirect avidin-biotin complex immunoperoxidase method, and 3-amino-9-ethyl-carbazole as substrate.

FINDINGS

The sensitivity, specificity, positive predictive value, and diagnostic accuracy of this test method (for coexpression of the two markers) in the prospective analysis were 88%, 98%, 91%, and 97%, respectively. The sensitivity and specificity of galectin-3 immunodetection alone in discriminating benign from malignant thyroid lesions were more than 99% and 98% respectively, and the positive predictive value and diagnostic accuracy were 92% and 99%.

INTERPRETATION

The integration of galectin-3 immunostaining with conventional cytomorphological and clinical diagnostic procedures represents a sensitive and reliable diagnostic approach for preoperative identification of thyroid carcinomas. This test method improves the diagnostic accuracy of conventional cytology and provides the molecular basis for a new nosological assignation of the not yet classified thyroid neoplasms of indeterminate malignant behaviour.

DNA copy number changes in familial malignant mesothelioma

Malignant mesothelioma (MM) is predominantly a sporadic malignancy linked to exposure to asbestos. Clustering of MM in families suggests genetic susceptibility as a contributing factor. We performed comparative genomic hybridization (CGH) analysis on tumor samples from members of a family with MM of the pleura and a history of parental cancer. Our specific aim was to find a recurrent copy number loss indicating the chromosomal area to which a gene underlying the development of MM could be assigned according to the Knudson two-hit hypothesis. We found losses at 1p, 6q, 9p, 13q, and 14q. The copy number changes were very similar to those reported in sporadic cases. Our findings and results from sporadic cases highlight the importance of cloning the genes in the loss sites at 1p, 6q, 14q, and 22q.

Isolated oropharyngeal Kaposi's sarcoma in non AIDS patient: differences and similarities with spindle-cell haemangioendothelioma

Vascular tumours rarely affect the oropharynx and overall they can represent a diagnostic challenge since their clinico-histopathological patterns are not always clear. This case report, of an isolated pharyngeal vascular proliferation, allowed the authors to analyse the similarities and differences between Kaposi's sarcoma and spindle-cell haemangioendothelioma. Moreover, it emphasizes the importance of diagnostic tools, such as the human herpesvirus 8 (HHV8) marker, that sometimes may represent the only reliable test for clearly establishing the diagnosis.

Estrogen prevents the lipopolysaccharide-induced inflammatory response in microglia

After neuronal injury and in several neurodegenerative diseases, activated microglia secrete proinflammatory molecules that can contribute to the progressive neural damage. The recent demonstration of a protective role of estrogen in neurodegenerative disorders in humans and experimental animal models led us to investigate whether this hormone regulates the inflammatory response in the CNS. We here show that estrogen exerts an anti-inflammatory activity on primary cultures of rat microglia, as suggested by the blockage of the phenotypic conversion associated with activation and by the prevention of lipopolysaccharide-induced production of inflammatory mediators: inducible form of NO synthase (iNOS), prostaglandin-E(2) (PGE(2)), and metalloproteinase-9 (MMP-9). These effects are dose-dependent, maximal at 1 nm 17beta-estradiol, and can be blocked by the estrogen receptor (ER) antagonist ICI 182,780. The demonstration of ERalpha and ERbeta expression in microglia and macrophages and the observation of estrogen blockade of MMP-9 mRNA accumulation and MMP-9 promoter induction further support the hypothesis of a genomic activity of estrogen via intracellular receptors. This is the first report showing an anti-inflammatory activity of estrogen in microglia. Our study proposes a novel explanation for the protective effects of estrogen in neurodegenerative and inflammatory diseases and provides new molecular and cellular targets for the screening of ER ligands acting in the CNS.

Primary effusion lymphoma in HIV-infected patients with multicentric Castleman's disease

Multicentric Castleman's disease (MCD) and primary effusion lymphoma (PEL) are two B-cell lymphoproliferative diseases associated with Kaposi's sarcoma-associated herpes virus/human herpesvirus-8 (KSHV/HHV-8). Although MCD is considered a prelymphoma state, it is not known whether a pathogenetic link exists between MCD and PEL. This paper reports the clinico-pathological features of four cases of PEL (two pericardial, one pleural, and one peritoneal) developing in the context of HIV-associated MCD. Effusions, lymph nodes, spleen, and additional tissues from three autopsies were examined for morphology/immunophenotype, search for HHV-8 DNA, and assessment of immunoglobulin heavy chain gene (IgH) configuration using polymerase chain reaction (PCR)-based techniques. MCD and PEL samples contained HHV-8 DNA. Clonal IgH rearrangements were detected only in PEL, whereas MCD tissues were polyclonal. Light-chain immunostaining confirmed B-cell clonality in PEL (two lambda, one kappa, one not tested) and polyclonality in MCD. The autopsies revealed different morphological variants of visceral KS and multi-organ atypical infiltrates exhibiting immunoblastic/plasmablastic features reminiscent of PEL morphology, with a restriction of lambda-positive cells. In two cases, using microdissection and IgH PCR analysis, multiple/discrete bands were found in the infiltrates, compatible with polyclonality/oligoclonality. The case showing an oligoclonal IgH ladder contained a rearrangement of identical junctional size to the PEL clone; however, further analysis with PEL-derived clonotypic primers and sequencing of PCR products showed no amplification and nucleotide diversity, respectively, indicating that the two B-cell populations examined were clonally unrelated. These data show that MCD and PEL may co-exist in HIV-infected patients, suggesting a relevant association between these two HHV-8-related disorders. Although a definite clonal relationship between MCD and PEL was not demonstrated, it is hypothesized that in some MCD cases, within expanded polyclonal B-cell populations secondary to HHV-8 infection, clonal expansions may occur that localize into a body cavity, i.e. PEL.

[Malignant mesothelioma in the industrial area of Colleferro]

The study describes the occurrence of pleural and peritoneal malignant mesothelioma in the Colleferro industrial area (Province of Rome, 9 municipalities, population 63,000, period 1993-98) which is the site of a large chemical plant (BPD) producing organic chemicals, acid mixtures, insecticides, explosives and dynamite, and was involved in manufacturing/maintenance of railroad rolling stock. Asbestos was extensively used in these plants in the past. Mesothelioma cases were actively searched from data in files of pathology archives, hospital admission and discharge (records), and death certificates recorded at local health authority register. 23 potential cases were identified for whom clinical charts and pathological slides were reviewed. A multidisciplinary evaluation of all collected information confirmed 18 cases of cyto-histologically proven malignant mesothelioma (pleural/peritoneal ratio of 2.75:1) among residents and/or workers at BPD. The remaining 5 cases were defined as not mesothelioma; however, two were cases of lung cancer (both occupationally exposed to asbestos). All subjects with malignant mesothelioma had been occupationally exposed to asbestos (14 males and 3 females), except one (1 female with domestic exposure). No mesothelioma case was attributable to environmental exposure. Of the 17 cases with occupational asbestos exposure, 15 occurred in BPD workers employed in manufacturing/maintenance of railroad rolling stock (3 cases), general maintenance services (5 cases), or in the armaments sector (7 cases) and 2 in residents but not BPD workers (1 baker, 1 pipefitter). The incidence rate in residents of the 9 municipalities was 5.5 in males and 1.3 in females (standardized on the Italian population x100,000, census 1981). For Colleferro municipality only, the incidence was 10.1 in males and 4.1 in females, which are the highest rates reported so far in Italy. Besides confirming the risk of mesothelioma risk in railroad rolling stock manufacturing and asbestos-insulated pipe maintenance workers, this study identifies a cluster of malignant mesothelioma in explosives production workers.

Diabetes influences the effect of 17beta-estradiol on mechanical responses of rat urethra and detrusor strips

Estrogen deficiency is one of the factors involved in the stress incontinence in postmenopausal women, and estrogens have been used clinically in the treatment of urinary disorders during menopause. Sex hormones seem to be also involved in the diabetic changes of urinary bladder and urethra, because ovariectomy causes an increase in the micturition of streptozotocin-diabetic rats. In the present study diabetic and healthy female rats were used to investigate the effect of 17beta-estradiol on mechanical contractions to norepinephrine and to KCI and relaxations to ATP on isolated proximal urethral preparations as well as on contractions to ACh, ATP and KCl on detrusor smooth muscle strips. The data were compared with those obtained in OVX animals, with or without estradiol replacement. The present study showed that ovariectomy decreased the responses to ATP, NE and KCl in urethral preparations, and responses to ATP, ACh and KCl in bladder strips from both healthy and diabetic rats. Diabetes appeared to potentiate the effect of ovariectomy in both tissues. Estrogen replacement was able to recover functional responses in urethras of healthy rats. In diabetic rats, this treatment partially restored ATP-induced responses in both tissues, almost completely restored those to NE in urethra and those to ACh in bladder. This study clearly indicated that abnormalities of urethra and bladder function caused by ovariectomy can be restored by estrogen treatment also in diabetic animals, at least at an early stage of disease.

The cisproline(i - 1)-aromatic(i) interaction: folding of the Ala-cisPro-Tyr peptide characterized by NMR and theoretical approaches

Cisproline(i - 1)-aromatic(i) interactions have been detected in several short peptides in aqueous solution by analysis of anomalous chemical shifts measured by 1H-NMR spectroscopy. This formation of local structure is of importance for protein folding and binding properties. To obtain an atomic-detail characterisation of the cisproline(i - 1)-aromatic(i) interaction in terms of structure, energetics and dynamics, we studied the minimal peptide unit, blocked Ala-cisPro-Tyr, using computational and experimental techniques. Structural database analyses and a systematic search revealed two groups of conformations displaying a cisproline(i - 1)-aromatic(i) interaction. These conformations were taken as seeds for molecular dynamics simulations in explicit solvent at 278 K. During a total of 33.6 ns of simulation, all the 'folded' conformations and some 'unfolded' states were sampled. 1H- and 13C-chemical shifts and 3J-coupling constants were measured for the Ala-Pro-Tyr peptide. Excellent agreement was found between all the measured and computed NMR properties, showing the good quality of the force field. We find that under the experimental and simulation conditions, the Ala-cisPro-Tyr peptide is folded 90% of the time and displays two types of folded conformation which we denote 'a' and 'b'. The type a conformations are twice as populated as the type b conformations. The former have the tyrosine ring interacting with the alanine alpha proton and are enthalpically stabilised. The latter have the aromatic ring interacting with the proline side chain and are entropically stabilised. The combined and complementary use of computational and experimental techniques permitted derivation of a detailed scenario of the 'folding' of this peptide.

Androgen deprivation, estrogen treatment and vascular function in male rat aorta

The beneficial effects of estrogen on arterial function in women are well established, whereas studies concerning the vascular role of androgens have produced conflicting results. In the present study, we examined the effects of androgen deprivation and of estrogen treatment on vascular responses in male rats. Vascular reactivity was studied in aortic rings excised from intact and castrated rats, which had been implanted with capsules containing either 17beta-estradiol (E2) or its vehicle for 5 days. Contractile responses to noradrenaline were potentiated by castration and by E2 treatment. Concentration-response curves for N-methyl-L-arginine and superoxide dismutase indicated that the tone-related release of NO increased in tissues from castrated, compared with intact rats, but was not affected by E2 treatment. Endothelium-dependent relaxation elicited by carbachol and histamine were not altered by castration and were attenuated by E2 in preparations from intact, but not from castrated rats. Moreover, aortic prostacyclin release dropped by about 40% after E2 treatment in tissues from both intact and castrated animals. Similarly, smooth muscle sensitivity to NO significantly decreased following castration and E2 treatment, as assessed by responses to sodium nitroprusside. Finally, no differences among groups were detected in platelet thromboxane A2 production. Thus, vascular responses in male rats were not improved by androgen deprivation alone or by E2 treatment, whose effects differed in the presence or absence of androgens. These findings provide evidence for the gender specificity of the vascular effects of estrogen and may be consistent with a beneficial role of physiologic levels of male sex hormones in arterial function.

[The extempore intraoperative cytology of peritoneal lavage fluid. A study of the reliability of the method]

Data are presented about a 100 cases prospective study, designed to evaluate sensibility/specificity of intra-operative cytology on peritoneal washing in case of cancer of digestive tract. Data analysis showed a very low sensibility of the test (according with most of literature observations) that does not allow to consider it fully reliable. Authors, thus, suggest a critical use of the test and state doubts about his real value in the intra-operative correct managing of therapeutic options.

Human herpesvirus-8 in lymphomatous and nonlymphomatous body cavity effusions developing in Kaposi's sarcoma and multicentric Castleman's disease

Human herpesvirus-8 (HHV-8) has been associated with Kaposi's sarcoma, multicentric Castleman's disease and primary effusion lymphoma. Kaposi's sarcoma and multicentric Castleman's disease patients may develop body cavity effusions that, unlike primary effusion lymphoma, are poorly characterized. To better define these effusions, pleural and peritoneal fluids derived from 12 human immunodeficiency virus-seropositive and one seronegative patients affected by Kaposi's sarcoma or multicentric Castleman's disease were analyzed by a combination of morphologic, immunophenotypic, and DNA analyses, including polymerase chain reaction amplification of HHV-8, Epstein-Barr virus, and immunoglobulin heavy-chain (IgH) gene sequences. In addition, HHV-8 serologic status was assessed by using an immunofluorescence assay. All patients were adult men with high antibody titers to HHV-8; 11 of the 13 patients were homosexual/bisexual. Effusions revealed monocyte/macrophage-rich infiltration (10 patients) or large-cell lymphoma with CD45(+)/non-T/non-B phenotype (three of 13 patients); polymerase chain reaction analysis showed the presence of HHV-8 sequences (nine of 13 patients), germline IgH (seven of 12 patients) or clonal IgH rearrangements (four of 12 patients), and rarely Epstein-Barr virus sequences (two of 12 patients). In the setting of HHV-8 infection, two effusion types may occur. One fulfills the criteria for HHV-8-positive PEL (lymphoma-morphology, HHV-8-DNA(+), IgH rearrangement). The other seems more reminiscent of an HHV-8-associated nonneoplastic process (monocyte-macrophage morphology, HHV-8-DNA(+/-), germline IgH). Interestingly, a single case of the latter effusion type harbored a B-cell monoclonal proliferation, which suggests the hypothesis that a prelymphomatous effusion may precede overt body cavity lymphoma.

Spiral CT of the abdomen after distention of small bowel loops with transparent enema in patients with Crohn's disease

BACKGROUND

[corrected] To evaluate the capability of a computed tomographic (CT) technique that combines distention of the small bowel loops with a transparent enema with contrast-enhanced spiral CT of the abdomen in patients with Crohn's disease.

METHODS

We evaluated the abdomen with spiral CT after distention of the small bowel loops with a transparent enema of methylcellulose in 40 patients consecutively referred for radiologic evaluation of Crohn's disease of the small bowel. Fluid was infused through a nasojejunal catheter with a peristaltic pump. Ultrasonography was used to prevent bowel overdistention and detect arrival of methylcellulose to the cecum. Contrast-enhanced spiral CT of the abdomen was then performed, and the degree of contrast enhancement and the thickness of the walls of the involved loops were evaluated. A series of 10 patients with retrograde distention of the last ileal loop from large bowel water enema was used as a control. The results of the CT were compared with those of conventional radiographic small bowel studies.

RESULTS

The normal small bowel wall was 1.9-2.5 mm thick (mean = 2. 1 mm); density values of the normal enhanced wall varied between 25 and 60 HU (mean = 32 HU) and presented a homogeneous structure. Bowel segments involved by the disease were 4-12.5 mm thick (mean = 9.2 mm), had density values of 75-150 HU (mean = 105 HU), and showed a multilayered appearance. Compared with conventional radiography, CT detected longer lesions or additional segments involved by the disease process in 14 cases, 11 additional fistulas, two abscesses, and mesenteric changes in 21 cases.

CONCLUSIONS

The small bowel CT enema technique provides good results in the study of patients with Crohn's disease and can be used to evaluate patients with advanced lesions.