C/EBPbeta is over-expressed in gastric carcinogenesis and is associated with COX-2 expression

The CCAAT/enhancer-binding protein beta (C/EBPbeta) transcription factor has been associated with several cancer models. In this study, the expression of C/EBPbeta was analysed in a series of 90 gastric carcinomas (GCs). We also assessed the effect of C/EBPbeta on COX-2 expression. In normal gastric mucosa, C/EBPbeta expression was restricted to cells in the proliferative zone. In intestinal metaplasia, dysplasia, and GC of the intestinal and atypical subtypes, C/EBPbeta was over-expressed (p < 0.0001, for the association with histological type). C/EBPbeta and Ki67, a marker of cell proliferation, were also co-expressed in primary GC. We also observed an overlap between C/EBPbeta and COX-2 expression in GC. Using GC cell lines we show that C/EBPbeta can regulate the expression of endogenous COX-2 and transactivate the promoter of the COX-2 gene, depending on its methylation status. These results suggest that C/EBPbeta may be a marker of neoplastic transformation and also play an active role in gastric tumourigenesis by regulating COX-2 expression.

Diagnóstico e tratamento do nódulo solitário da tiróide: estudo de avaliação em Portugal

Introdução – A melhor estratégia diagnóstica e terapêutica em relação à abordagem da doença nodular da tiroideia, continua a ser um assunto controverso. Objectivos – Este estudo teve como objectivo caracterizar a prática médica, relativamente ao diagnóstico e tratamento da patologia nodular da tiroideia, de endocrinologistas e cirurgiões, em Portugal, em 2002. Métodos – Foi elaborado um questionário baseado no já utilizado pela European Thyroid Association e pela American Thyroid Association. Este questionário foi distribuído pela Sociedade Portuguesa de Endocrinologia, a médicos endocrinologistas e cirurgiões, tendo em conta um caso clínico bem definido, de uma mulher de 42 anos com nódulo solitário da tiróide com 2 x 3 cm, sem história de disfunção ou sintomas dolorosos. Cada médico deveria responder quais os procedimentos diagnósticos e terapêuticos que adoptaria no caso em referência. Onze variações ao caso inicial foram propostas de forma a avaliar as alterações efectuadas para cada alteração introduzida. Resultados – Foram enviados 1492 questionários, 163 a médicos endocrinologistas e 1329 a cirurgiões, tendo-se recebido um total de 104 respostas. A taxa de respostas global foi de 7%. A taxa de respostas dos endocrinologistas foi de 27% e dos cirurgiões de 4,5%. Dos 104 questionários recebidos, 42% provinham de endocrinologistas e 58% de cirurgiões. Em relação aos exames analíticos pedidos, os cirurgiões utilizaram mais analises do que os endocrinologistas para o caso clínico em estudo. As principais diferenças em termos laboratoriais consistiram num maior número de pedidos de T4 e T3 totais e tiroglobulina pelos cirurgiões, e mais pedidos de AATPO pelos endocrinologistas. O número médio de análises foi de 4,6, sendo de 4,1 para os endocrinologistas e 5,1 para os cirurgiões. Quanto à imagiologia e citologia, 32% dos médicos inquiridos advogaram uma cintigrafia para o estudo do caso clínico, não se registando diferenças significativas entre endocrinologistas e cirurgiões. A ecografia foi utilizada por mais de 85% dos inquiridos. 90% pediram uma citologia, dos quais 83% orientada por palpação e 18% eco-guiada. Em relação ao tratamento, 33% dos médicos preconizaram tratamento com levotiroxina, sendo a cirurgia proposta por 16,3% dos endocrinologistas e 36,6% dos cirurgiões. No entanto, a maioria dos médicos (68%) optaria por não efectuar qualquer tratamento mantendo apenas a doente em vigilância. Conclusões – Existem diferenças importantes na forma de abordagem da doença nodular tiroideia, entre os vários médicos e os vários especialistas, sublinhando-se a dificuldade existente em atingir um consenso diagnóstico e terapêutico.

[Diagnosis and treatment of solitary thyroid nodule--study and evaluation in Portugal]

INTRODUCTION

The best diagnostic and treatment strategy for an approach to the nodular thyroid disease continues to be a controversial issue.

OBJECTIVES

The aim of this study was to characterise medical practice in the diagnosis and treatment of nodular thyroid disease by endocrinologists and surgeons in Portugal in 2002.

METHODS

A questionnaire based on that used by the European Thyroid Association and the American Thyroid Association was drawn up. The questionnaire, based on a well-defined index case, was circulated by the Portuguese Endocrinology Society to endocrinologists and surgeons: 42 year-old woman with solitary thyroid nodule measuring 2 x 3 cm, with no history of malfunction or painful symptoms. Each doctor was asked to reply as to the adopted diagnosis and therapy procedures for the index case. Eleven variations to the original case were proposed in order to evaluate the alterations for each variation.

RESULTS

1492 questionnaires were sent out, 163 to endocrinologists and 1329 to surgeons. A total of 104 were returned. The global response rate was 7%. The response rate for endocrinologists was 27% and 4.5% for surgeons. Of the 104 questionnaires returned, 42% were from endocrinologists and 58% from surgeons. Concerning tests prescribed, surgeons would use more tests than endocrinologists for the index case. The main differences in laboratory terms were the higher number of prescriptions for total T4 and T3 and thyroglobulin by surgeons and more prescriptions for AATPO by endocrinologists. The average number of tests was 4.6, 4.1 for endocrinologists and 5.1 for surgeons. Relative to imaging and cytology, 32% of doctors advocated a scintigraphy to diagnose the index case, with no significant differences between endocrinologists and surgeons. Ultrasonography was used by over 85% of respondents. 90% prescribed a cytology, 83% guided by palpation and 18% ultrasonography-guided. Concerning treatment, 33% of doctors advocated levothyroxin treatment; surgery was advocated by 16.3% of endocrinologists and 36.6% of surgeons. Meanwhile, the majority of doctors (68%) would opt for no treatment and simply maintain the patient under surveillance.

CONCLUSIONS

There are important differences in the approach to nodular thyroid disease among the various doctors and specialists, which highlight the difficulty in achieving a diagnostic and therapeutic consensus.

[Treatment and follow up protocol in differentiated thyroid carcinomas of follicular origin]

Differentiated thyroid carcinoma of follicular origin (DTCFO), although not very frequent, has registered a raising incidence in the last decades. In the majority of the cases, DTCFO is a curable disease when treated and monitored by experienced, multidisciplinary teams. These factors contribute to an increasing number of DTCFO survivors requiring life-long monitoring, due to the possibility of occurrence of recurrences many years after the initial treatment. Several aspects of the treatment and management of these patients are still controversial. The present protocol represents the consensus of the members of the Grupo de Estudo da Tiróide of the Sociedade Portuguesa de Endocrinologia, Diabetes e Metabolismo. It aims to define guidelines, in agreement with the current state of the art and contemplating the necessary adaptations to local constrains, that ensure decreased mortality and protection of patients' quality of life, avoiding unnecessarily aggressive or ineffective treatments, optimizing the use of the available resources.

Germline E-cadherin mutations in hereditary diffuse gastric cancer: assessment of 42 new families and review of genetic screening criteria

BACKGROUND

Mutations in the E-cadherin (CDH1) gene are a well documented cause of hereditary diffuse gastric cancer (HDGC). Development of evidence based guidelines for CDH1 screening for HDGC have been complicated by its rarity, variable penetrance, and lack of founder mutations.

METHODS

Forty three new gastric cancer (GC) families were ascertained from multiple sources. In 42 of these families at least one gastric cancer was pathologically confirmed to be a diffuse gastric cancer (DGC); the other family had intestinal type gastric cancers. Screening of the entire coding region of the CDH1 gene and all intron/exon boundaries was performed by bi-directional sequencing.

RESULTS

Novel mutations were found in 13 of the 42 DGC families (31% overall). Twelve of these mutations occur among the 25 families with multiple cases of gastric cancer and with pathologic confirmation of diffuse gastric cancer phenotype in at least one individual under the age of 50 years. The mutations found include small insertions and deletions, splice site mutations, and three non-conservative amino acid substitutions (A298T, W409R, and R732Q). All three missense mutations conferred loss of E-cadherin function in in vitro assays. Multiple cases of breast cancers including pathologically confirmed lobular breast cancers were observed both in mutation positive and negative families.

CONCLUSION

Germline truncating CDH1 mutations are found in 48% of families with multiple cases of gastric cancer and at least one documented case of DGC in an individual under 50 years of age. We recommend that these criteria be used for selecting families for CDH1 mutational analysis.

Bulging mesothelial cells of the visceral pleura of the rat mimic the network of subpleural lymphatics

The mesothelial surface of the visceral pleura of the Wistar rat was viewed at high resolution by scanning electron microscopy (SEM). The pleural surface showed exquisite linear arrangements made up of bulging mesothelial cells. They were organized in irregular circles that often presented anastomotic junctures. This arrangement of pleural mesothelial cells mimics the organization of subpleural lymphatics of the lung. A low density of microvilli was seen inside the irregular circles, contrasting with the microvilli-rich mesothelial cells seen on or outside these arrangements. These SEM features of the mesothelium may be related with the formation of microdomains for fluid absorption across the visceral pleura into subpleural lymphatics.

[Hypothyroidism and pregnancy]

The authors refer hypothyroidism epidemiology and physiology, enhancing the need to raise thyroid hormones and also to adjust the doses of levothyrosine, normally used in the treatment. They describe the obstetric complications that can occur in non medicated hypothyroidism pregnancies, as well to the new-born baby.

In utero and postnatal exposure of Wistar rats to low frequency/high intensity noise depletes the tracheal epithelium of ciliated cells

Chronic exposure of men or rodents to low frequency/high intensity (LFHI) noise causes a number of systemic changes that make up the so-called vibroacoustic disease (VAD), a disorder that includes alterations of the respiratory system, namely, of its epithelial layer. We have investigated here the susceptibility of the tracheal epithelium of Wistar rats to in utero and postnatal exposure to LFHI noise by comparing its ultrastructure with that of the tracheal epithelium of control rats and of animals exposed to LFHI noise only after reaching adulthood (8 weeks of age). Scanning electron microscopy (SEM) of the inner surface of rat trachea was used to determine the relative areas covered by ciliated and non-ciliated cells. In rats that were exposed in utero and postnatally to LFHI noise, we observed that out of 100 microm(2) of tracheal epithelium only 31 +/- 14 microm(2) were covered by cilia, whereas in control rats; ciliated cells occupied an average of 60 +/- 18 microm(2) out of 100 microm(2) of the epithelium; this difference between the two groups was statistically significant (p <0.05). In rats that were exposed to LFHI noise only after reaching adulthood, cilia covered 55 +/- 22 microm(2) out of 100 microm(2) of the luminal surface of the trachea, a value that, although lower than that of controls, was not found to be statistically different. We conclude that (1) the tracheal ciliated cells are damaged by exposure of rats to LFHI noise if the animals are kept under this environmental aggression during in utero and postnatal periods; (2) tracheal ciliated cells from adult rats are more resistant to the deleterious effects of LFHI noise than pleura or lung alveolar cells that were shown before to undergo marked changes upon chronic exposure of rats to LFHI noise. These findings suggest a note of caution regarding pregnant women and young children: they should be prevented from areas where LFHI noise occurs, namely, in aircraft and textile industries where this type of environmental hazard is often present.

Detection of circulant tumor necrosis factor-alpha, soluble tumor necrosis factor p75 and interferon-gamma in Brazilian patients with dengue fever and dengue hemorrhagic fever

Pro-inflammatory cytokines are believed to play an important role in the pathogenesis of dengue infection. This study reports cytokine levels in a total of 54 patients examined in Recife, State of Pernambuco, Brazil. Five out of eight patients who had hemorrhagic manifestations presented tumor necrosis factor-alpha (TNF-alpha) levels in sera which were statistically higher than those recorded for controls. In contrast, only one out of 16 patients with mild manifestations had elevated TNF-alpha levels. The levels of interleukin-6 (IL), IL-1beta tested in 24 samples and IL-12 in 30 samples were not significantly increased. Interferon-g was present in 10 out of 30 patients with dengue. The data support the concept that the increased level of TNF-alpha is related to the severity of the disease. Soluble TNF receptor p75 was found in most patients but it is unlikely to be related to severity since it was found with an equivalent frequency and levels in 15 patients with dengue fever and another 15 with dengue hemorrhagic fever.

Molecular mechanisms of invasion by cancer cells, leukocytes and microorganisms

Invasion is a phenotype common to cancer cells, leukocytes, parasites, bacteria and viruses, involving cell-cell adhesion, cell-matrix adhesion, proteolysis and motility. These activities are regulated by the cross talk between invaders and host. We discuss the invasion-related molecular interactions of E-cadherin, integrins, matrix metalloproteinases and the chemokine receptor RANTES.

Diversity of cyanobacterial hydrogenases, a molecular approach

In an effort to elucidate the diversity of cyanobacterial hydrogenases, we used a molecular approach. Filamentous strains from a broad range of sources were screened for the presence of hup (uptake hydrogenase), xisC (rearrangement within hupL), and hox (bidirectional hydrogenase) genes. As expected, an uptake hydrogenase seems to be present in all N(2)-fixing cyanobacteria. On the other hand, no evidence was found for the presence of a conventional bidirectional enzyme in several strains. Similarly, the presence of xisC is not a characteristic shared by all the heterocyst-forming cyanobacteria. Although tempting, it is not possible to establish a correlation between the presence/absence of the bidirectional hydrogenase and the occurrence of xisC. The natural molecular variation of hydrogenases in cyanobacteria is certainly a field to explore, both to understand the physiological functions of the respective enzymes and to identify a genetic background to be used when constructing a strain for photobiological H(2) production in a bioreactor.

[Status epilepticus in the childhood. A review of seven years]

INTRODUCTION

Status epilepticus is a neurological emergency that requires early and prompt treatment.

PATIENTS AND METHODS

This retrospective study includes 32 children treated for status epilepticus at Hospital Geral de Santo António, from January 1992 to December 1998. We evaluated the clinical features, duration, aetiology and prognostic.

RESULTS

Symptomatic or criptogenetic aetiology was present in 53% of children and idiopathic in 47%. 27% of episodes of status epilepticus were induced by fever. The most common neurological sequel was epilepsy (onset of new epilepsy in 20%; aggravated in 25%). Two children (10%) had major neurological sequelae after status epilepticus.

CONCLUSION

In our study the duration of status epilepticus and sequelae seems to be related with aetiology.

Effects of low frequency noise upon the reaction of pleural milky spots to mycobacterial infection

INTRODUCTION

Milky Spots (m.s.), also known as Kampmeier's foci, are confined to the parietal leaflet and act as a barrier to mediastinum infections, having very important phagocytic functions. Previous studies have made clear that large pressure amplitude and low frequency (LPALF) noise (> or = 90 dB, < or = 500 Hz) induces morphofunctional changes on the pleural mesothelium. The purpose of this study was to investigate the dynamics of m.s., namely the response to infectious agents reaching the pleural space under noise stress.

METHODS

Wistar rats (n = 20) were used; 5 as control and sham operated, 5 exposed to infection but not to noise, 5 exposed to 1696 cumulative hours of LPALF noise, and 5 exposed to 2184 cumulative hours. Following noise exposures, all rats except the 5 controls were injected with 0.2 ml of saline solution containing 2 x 10(8) viable mycobacterium avium bacilli (ATCC-25291 strain, sereotype 2). The rats were sacrificed 21 d after infection and sections of the retrocardiac pleural leaflets were observed with a light microscope using the Ziehl-Neelsen staining method.

RESULTS

There was an increase in the number and diameter of the m.s. due to hypercellularity, mainly caused by the increase of mononuclear cells, and there was formation of large granulomas containing many mycobacteria. Rats submitted to noise also presented alterations of the standard morphological changes, namely partial necrosis of the m.s.

CONCLUSION

The data suggest that exposure to LPALF noise can interfere with the normal immune response to bacterial infection in rats. This can be an important contribution to the understanding of the disorders in the pleural space of vibroacoustic disease patients.

Pure red cell aplasia due to persistent B19 parvovirus infection in patient infected with human immunodeficiency virus type 1. Recovery with alpha-interferon therapy

B19 parvovirus (PV) infection is ordinarily resolved with the production of specific antibodies that neutralize virus infectivity for erythroid host cells. Nevertheless persistent infection with B19 PV and pure red blood cell aplasia have been documented. A 27 year-old male. i.v. drug abuser, HIV+ and HCV was diagnosed of pure red cell aplasia. Six months later we had serologic evidence of persistent parvovirus infection. Interferon therapy, started for HCV infection, showed a marked improvement of anaemia and anti parvovirus IgM became negative. It is discussed the possible role of interferon therapy in persistent parvovirus infection.

Poliovirus type 1 isolated from a vaccine-associated case of paralytic poliomyelitis in Brazil

This study reports a type 1 poliovirus strain isolated in Brazil from a case classified as vaccine-associated paralytic poliomyelitis (VAPP). After serotyping of the viral isolate with hyperimmune equine sera, PCR and molecular hybridization techniques characterized the strain as P1/Sabin-derived. The isolate was partially sequenced to identify mutations at nucleotides 480, 525 and 6203, which are important for reversion of the P1/Sabin strain to neurovirulence. In a recent study, a P1/Sabin-derived strain isolated from the central nervous system of a VAPP case did not mutate at these positions, but maintained 480-G and 525-U (and 6203-C), suggesting that these mutations are not essential for the occurrence of disease (Georgescu et al., (1994), Journal of Virology, 68: 8089-8101). Although the Brazilian strain also maintained 480-G and 525-U (and 6203-C) and was isolated from the stool, the possibility that this isolate invaded the central nervous system after replicating in the gut, causing the paralysis, cannot be ruled out. This is the first report of a type 1 VAPP case in Brazil, although some cases caused by type 2 and type 3 strains have been described.

Experimental modulation of the reactivity of pleural milky spots (Kampmeier's foci) by Freund's adjuvants, betamethasone and mycobacterial infection

We studied the response of milky spots in the parietal pleura of the rat and mouse to intrapleural instillation of immunomodulatory agents such as complete or incomplete Freund's adjuvants and betamethasone, and also to infection by mycobacteria (M. avium). Both incomplete (mineral oil) and complete (mineral oil plus dead mycobacteria) adjuvants, as well as M. avium infection, induced a striking increase in the size and cellularity of the pleural milky spots whereas betamethasone caused a slight atrophy. The extensive inflammatory infiltrates observed after adjuvant injection differed between milky spots reactive to complete and incomplete Freund's adjuvants. Fifteen days after adjuvant administration, the pleural milky spots of rats were still enlarged and hypercellular but differences were noted in the size of milky spots of the pleura between the 2 adjuvant treatments: animals submitted to injection of complete Freund's adjuvant showed an increase in the size of milky spots from d 3 to d 15, while the size of milky spots of the incomplete Freund's adjuvant treated group showed a decrease in size from d 3 to d 15. The milky spots at d 15 were well organised: reticulin fibres permeated the whole area of the milky spot and the different cell types were evenly distributed. Histiocytes, which were previously confined to the inner layer, were now the main cell type in all areas of milky spots. A moderate number of mast cells and a few eosinophils were also seen. Complete Freund's adjuvant caused the formation of granulomas in the milky spots, a change that was not detected in animals treated with incomplete adjuvant.(ABSTRACT TRUNCATED AT 250 WORDS)

Oligonucleotide probes for the specific detection of the wild poliovirus types 1 and 3 endemic to Brazil

Synthetic oligodeoxynucleotide probes, 21-23 nucleotides in length, were prepared which specifically hybridize to the genomes of the wild type 1 and 3 polioviruses currently endemic to the northeastern region of Brazil. The probes are complementary to sequences near the 5'-terminus of the VP1 gene that differ substantially among genetically distant polioviruses but are largely conserved among related isolates. The probes have been routinely used in the laboratory surveillance of poliomyelitis cases in Brazil, permitting direct, rapid identification of the indigenous wild polioviruses by dot-blot hybridization.

Effects of the venom of the Brazilian scorpion Tityus serrulatus and two of its fractions on the isolated diaphragm of the rat

1. The effects of Tityus serrulatus venom and of two of its toxic fractions, toxin gamma (Tx gamma) and T2III1, on the rat isolated diaphragm were examined. 2. The crude venom (5 ng) facilitated the neuromuscular transmission and increased the twitch tension evoked by retrograde injection of Ach. 3. Tx gamma (25-100 ng) and fraction T2III1 (2.5 ng) also facilitated the neuromuscular transmission but only fraction T2III1 increased the twitch tension evoked by retrograde injection of Ach. 4. Tx gamma (50 ng) and fraction T2III1 (2.5 ng) produced a tetrodotoxin-sensitive increase in the frequency of miniature endplate potentials (m.e.p.p.) and a transitory reduction of the resting potential. The latter effect of the fractions was prevented by treating muscles with tetrodotoxin or D-tubocurarine. Fraction T2III1 also produced a tetrodotoxin-resistance increase of m.e.p.p. amplitude. 5. These results suggest that Tx gamma enhances Ach output through the activation of Na+ channels in the motor nerve terminals. Fraction T2III1 produced effects similar to those induced by Tx gamma but also acted at postjunctional sites, probably by increasing subsynaptic membrane sensitivity to the neurotransmitter.

Randomised trial of alternative formulations of oral poliovaccine in Brazil

In February to July, 1986, an outbreak of type 3 poliomyelitis occurred in north-east Brazil that was linked to type-specific failure of trivalent oral polio vaccine (TOPV). To see if alternative vaccines would improve seroconversion to type 3, 441 children less than 5 years of age who had previously received no or up to four doses of TOPV were randomly assigned to receive one dose of standard TOPV (1,000,000, 100,000, and 300,000 median tissue culture infection doses [TCID50] of types 1, 2, and 3, respectively); a new formulation of TOPV containing twice the dosage of type 3 (600,000 TCID50); or a monovalent vaccine containing 300,000 TCID50 of type 3. While rates of seroconversion to types 1 or 2 were equivalent following vaccination with either formulation of TOPV, children who received the new formulation were 2.7 times more likely to seroconvert to type 3. Similar differences for type 3 were observed when monovalent vaccine was compared with standard TOPV, though both groups had received the same dose of type 3 antigen. The low rate of seroconversion to type 3 in the standard TOPV group was associated with a higher rate of reinfection with type 2, which also appeared to interfere to some extent with seroconversion to type 1. These findings extend earlier observations that interference from Sabin type 2 virus may be an important contributory cause of type-specific TOPV failure, and suggest that interference can be overcome with alterations in the formulation.