Chromosome number variation and evolution in Neotropical Leguminoseae (Mimosoideae) from northeastern Brazil

Most members of the subfamily Mimosoideae have pantropical distributions, variable habits, and a basic chromosome number x = 13. We examined karyotypic evolution of 27 species of this subfamily occurring principally in northeastern Brazil by examining chromosomes stained with Giemsa. All of the species had semi-reticulated interphase nuclei and early condensing segments in the proximal region of both chromosome arms. The basic number x = 13 was the most frequent, with 2n = 2x = 26 in 19 of the species, followed by 2n = 4x = 52 and 2n = 6x = 78. However, the three species of the genus Calliandra had the basic number x = 8, with 2n = 2x = 16, while Mimosa cordistipula had 2n = 4x = 32. The karyotypes were relatively symmetrical, although bimodality was accentuated in some species, some with one or two acrocentric pairs. As a whole, our data support earlier hypotheses that the Mimosoideae subfamily has a basic number of x = 13 and underwent karyotypic evolution by polyploidy. However, x = 13 seems to be a secondary basic number that originated from an ancestral stock with x₁ = 7, in which polyploidy followed by descending disploidy gave rise to the current lineages with x = 13. Another lineage, including current representatives of Calliandra with x = 8, may have arisen by ascending disploidy directly from an ancestral monoploid stock with x₁ = 7.

Loss of CDC4/FBXW7 in gastric carcinoma

Background: CDC4/FBXW7, encoding a ubiquitin ligase, maps to 4q32 and has been implicated as a tumor suppressor gene and therapeutic target in many tumor types. Mutations in colonic adenomas, and the frequent losses on 4q described in gastric cancer prompt speculation about the role of CDC4/FBXW7 in gastric carcinogenesis.

Methods: We assessed the role of CDC4/FBXW7 in gastric cancer, through loss of heterozygosity (LOH) and multiplex ligation-dependent probe amplification (MLPA) on 47 flow-sorted gastric carcinomas including early-onset gastric cancers (EOGC) and xenografted conventional gastric carcinomas. Ploidy analysis was carried out on 39 EOGCs and immunohistochemistry of CDC4/FBXW7 and its substrates c-myc, c-jun, Notch and cyclin E was performed on 204 gastric carcinomas using tissue microarrays (TMAs). Sequence analysis of CDC4/FBXW7 was carried out on gastric carcinoma cell lines and xenografts.

Results: Loss of heterozygosity of CDC4/FBXW7 occurred in 32% of EOGCs, and correlated with loss of expression in 26%. Loss of expression was frequent in both EOGC and conventional gastric cancers. No CDC4/FBXW7 mutations were found and loss of CDC4/FBXW7 did not correlate with ploidy status. There was a significant correlation between loss of CDC4/FBXW7 expression and upregulation of c-myc.

Conclusions: Loss of CDC4/FBXW7 appears to play a role in both EOGC and conventional gastric carcinogenesis, and c-myc overexpression is likely to be an important oncogenic consequence of CDC4/FBXW7 loss.

First diabetes prevalence study in Portugal: PREVADIAB study

AIMS

Diabetes is a growing worldwide problem. Ascertaining its prevalence is vital as a starting point to establish and measure the success of health interventions. This study aimed to determine the prevalence of Type 2 diabetes and 'pre-diabetes', defined as impaired fasting glucose and impaired glucose tolerance, in the Portuguese population aged between 20 and 79 years.

METHODS

Considering the number of inhabitants between 20 and 79 years old, statistical units were selected that were representative regionally and nationally. The total sample comprised 5167 subjects. National prevalence was calculated. Analyses were performed on all those without previously known diabetes using World Health Organization reference diagnostic criteria.

RESULTS

We found a diabetes prevalence of 11.7% (95% confidence interval 10.8-12.6%), with a significant difference between men (14.2%; 95% confidence interval 12.5-15.5%) and women (9.5%; 95% confidence interval 8.5-10.6%). While 6.6% of the subjects had previously been diagnosed with diabetes, 5.1% were undiagnosed. By age groups, 2.4% of the population between 20 and 39 years, 12.6% of people from 40 to 59 years old and 26.3% of those aged between 60 and 79 years had diabetes. Prevalence of 'pre-diabetes' (impaired fasting glucose, impaired glucose tolerance or both) in the population was 23.3%.

CONCLUSIONS

Diabetes has a high prevalence in Portugal. If 'pre-diabetes' is also considered, about one-third (34.9%) of the population aged 20-79 years is affected. A greater number of males were found to have diabetes. We detected a high percentage of people with undiagnosed diabetes (43.6%).

Anterior Vocal Commissure Invasion in Laryngeal Carcinoma Diagnosis

BACKGROUND

Laryngeal carcinoma involving anterior vocal commissure (AVC) represents a great challenge for staging and treatment.

OBJECTIVES

To compare laryngoscopy and computed tomography (CT) scan efficiency in staging tumors extending to the AVC. We also analyzed the helicoidal axial CT scan accuracy in recognizing this larynx subregion invasion.

MATERIAL AND METHODS

Fifty-two glottic and supraglottic laryngeal squamous cell carcinoma patients with tumoral extension to the AVC were prospectively studied from August 2001 to August 2003 at the National Cancer Institute (Rio de Janeiro, Brazil). All patients underwent videolaryngoscopic examination and direct laryngoscopy for lesion extension analysis and biopsy. After AVC helicoidal axial CT scan with sagittal and coronal 1.0 mm thick reconstruction, patients were submitted to surgical treatment. The same pathologist analyzed all surgical specimens.

RESULTS

When compared with pathologic stage, clinical endoscopic classification was correct in 40.38% of cases (40% for T1, 29.41% for T2, 46.43% for T3, and 50% in T4). Helicoidal axial CT scan accuracy for AVC tumors was 75% (P = .0001), being more important for T2 (62.50%), T3 (73.91%), and T4 (88.24%) lesions. Identification of radiologic signs described as gross radiologic anterior commissure involvement (GRACI) increased radiologic image staging accuracy to over 96%.

CONCLUSIONS

Endoscopic evaluation understaged tumors in all clinical stages but really T1. Helicoidal axial CT scan reformatted to 1.0 mm thick played an important role in correctly staging more advanced AVC laryngeal tumors. Radiologic signs, here identified as GRACI, may be very helpful for tomographic staging and patient treatment.

Large genomic deletions of SMAD4, BMPR1A and PTEN in juvenile polyposis

BACKGROUND/AIMS

Juvenile polyposis syndrome (JPS) is a rare autosomal dominant disorder characterised by multiple gastrointestinal juvenile polyps and an increased risk of colorectal cancer. This syndrome is caused by germline mutation of either SMAD4 or BMPR1A, and possibly ENG. PTEN, originally linked to Cowden syndrome and Bannayan-Riley-Ruvalcaba syndrome, has also been associated with JPS. By direct sequencing, germline mutations are found in only 30-40% of patients with a JPS phenotype. Therefore, alternative ways of inactivation of the known JPS genes, or additional genes predisposing to JPS may be involved. In this study, a comprehensive genetic analysis of SMAD4, BMPR1A, PTEN and ENG is performed through direct sequencing and multiplex ligation-dependent probe amplification (MLPA) in JPS patients.

METHODS

Archival material of 29 patients with JPS from 27 families was collected. Direct sequencing and MLPA analysis were performed to search for germline defects in SMAD4, BMPR1A, PTEN and ENG.

RESULTS

A germline defect in SMAD4, BMPR1A or PTEN was found in 13 of 27 (48.1%) unrelated JPS patients. Nine mutations (33.3%) were detected by direct sequencing, including six (22.2%) SMAD4 mutations and three (11.1%) BMPR1A mutations. MLPA identified four additional patients (14.8%) with germline hemizygous large genomic deletions, including one deletion of SMAD4, one deletion of exons 10 and 11 of BMPR1A, and two unrelated patients with deletion of both BMPR1A and PTEN. No ENG gene mutations were found.

CONCLUSION

Large genomic deletions of SMAD4, BMPR1A and PTEN are a common cause of JPS. Using direct sequencing and MLPA, a germline defect was detected in 48.1% of JPS patients. MLPA identified 14.8% (4/27) of these mutations. Since a substantial percentage of JPS patients carry a germline deletion and MLPA is a reliable and user-friendly technique, it is concluded that MLPA is a valuable adjunct in JPS diagnosis.

Cyclin E low molecular weight isoforms occur commonly in early-onset gastric cancer and independently predict survival

BACKGROUND

Post-translational cleavage of full-length cyclin E from the N-terminus can produce low molecular weight (LMW) isoforms of cyclin E containing the C-terminus only.

AIM

To assess their presence in early-onset gastric cancer (EOGC), stump cancers and conventional gastric cancers and ascertain how they influence survival in EOGC.

METHODS

The expression of full-length and LMW isoforms of cyclin E in 330 gastric cancers, including early-onset gastric cancer (EOGC), stump cancer and conventional gastric cancer (>45 years old) was compared using antibodies targeted to the N- and C-terminals.

RESULTS

LMW isoforms were found in 35% of EOGCs, compared to 8% of conventional gastric cancers and 4% of stump cancers; their presence was visualised in cell lines using western blot analysis. In addition, C-terminal staining was a positive predictor of survival in EOGC. In contrast, no correlation with survival was found with the N-terminal antibody which detects only full-length cyclin E.

CONCLUSION

EOGCs have a unique molecular phenotype and LMW isoforms of cyclin E may independently influence survival in EOGC.

Genetic defects underlying Peutz-Jeghers syndrome (PJS) and exclusion of the polarity-associated MARK/Par1 gene family as potential PJS candidates

LKB1/STK11 germline inactivations are identified in the majority (66-94%) of Peutz-Jeghers syndrome (PJS) patients. Therefore, defects in other genes or so far unidentified ways of LKB1 inactivation may cause PJS. The genes encoding the MARK proteins, homologues of the Par1 polarity protein that associates with Par4/Lkb1, were analyzed in this study because of their link to LKB1 and cell polarity. The genetic defect underlying PJS was determined through analysis of both LKB1 and all four MARK genes. LKB1 point mutations and small deletions were identified in 18 of 23 PJS families using direct sequencing and multiplex ligation-dependent probe amplification analysis identified exon deletions in 3 of 23 families. In total, 91% of the studied families showed LKB1 inactivation. Furthermore, a MARK1, MARK2, MARK3 and MARK4 mutation analysis and an MARK4 quantitative multiplex polymerase chain reaction analysis to identify exon deletions on another eight PJS families without identified LKB1 germline mutation did not identify mutations in the MARK genes. LKB1 defects are the major cause of PJS and genes of the MARK family do not represent alternative PJS genes. Other mechanisms of inactivation of LKB1 may cause PJS in the remaining families.

Dissociation of the effects of ethanol on memory, anxiety, and motor behavior in mice tested in the plus-maze discriminative avoidance task

RATIONALE

Several studies have shown the amnestic effects of ethanol (ETOH). However, while memory tasks in rodents can be markedly influenced by anxiety-like behavior and motor function, ETOH induces anxiolysis and different effects on locomotion, depending on the dose.

OBJECTIVE

Verify the effects of ETOH in mice tested in the plus-maze discriminative avoidance task (PMDAT) concomitantly evaluating memory, anxiety-like behavior, and motor behavior.

METHODS

ETOH acutely or repeatedly treated mice were submitted to the training session in a modified elevated plus-maze with two open and two enclosed arms, aversive stimuli in one of the enclosed arms, and tested 24 h later without aversive stimuli. Learning/memory, locomotion, and anxiety-related behavior were evaluated by aversive arm exploration, number of entries in all the arms and open arms exploration, respectively.

RESULTS

Acute ETOH: (1) either increased (1.2-1.8 g/kg) or decreased (3.0 g/kg) locomotion; (2) decreased anxiety levels (1.2-3.0 g/kg); and (3) induced learning deficits (1.2-3.0 g/kg) and memory deficits (0.3-3.0 g/kg). After repeated treatment, sensitization and tolerance to hyperlocomotion and anxiolysis induced by 1.8 g/kg ETOH were observed, respectively, and tolerance to the amnestic effect of 0.6 (but not 1.8) g/kg ETOH occurred.

CONCLUSION

Neither the anxiolytic nor the locomotor effects of ETOH seem to be related to its amnestic effect in the PMDAT. Additionally, data give support to the effectiveness of the PMDAT in simultaneously evaluating learning, memory, anxiety-like behavior, and motor activity by different parameters. Possible relationships between the behavioral alterations found are discussed.

Pulmonary and cardiac cysticercosis: helical CT findings

The authors aim to report the chest CT findings of a patient with disseminated cysticercosis, emphasising the pulmonary and cardiac features. The main finding consisted of multiple pulmonary, cardiac and chest wall nodules. The present case demonstrates that cysticercosis should be considered in the differential diagnosis of multiple pulmonary nodules, mainly in those patients with similar lesions in the cardiac muscle and/or in the chest wall.

Serum carboxyterminal telopeptide (ICTP) as a prognostic marker in bone metastases (BM) treated with bisphosphonates

10107

Background: Biochemical markers of bone turnover, such as N- and C-terminal cross-linking telopeptide of type I collagen have been evaluated as prognostic matkers in patients with BM. In one of such study, we found that ICTP was not affected by bisphosphonate (BP) therapy (Costa, et al., JCO 2002; 20:850–856). In this prospective study we analyzed whether the baseline level of ICTP was predictive of skeletal related events (SREs) as defined by: pathologic fractures (PF), radiation to treat BM (RT) or spinal cord compression (SCC); time to progression (TTP) and overall survival (OS) in patients with BM from solid tumors under BP therapy. Methods: We studied 116 BM patients, median age: 64 years; 67% females; 61% breast cancer; 19% prostate cancer; and 20% other tumor types. The x-ray pattern of BM was lytic in 54% patients, blastic in 23%, and mixed in 21%. At the time of study entry, all patients had serum ICTP levels measured with RIA reagents from Orion Diagnostica (reference range: 2.5–4.0 μg/L). A serum ICTP cutoff of 6.2 μg/L was established using the mean + 2D. The occurrence of SREs was recorded during the study and an objective evaluation of BM status was performed every 4–6 months. During the time period on study, patients received treatment with IV zoledronate (57%), IV pamidronate (28%), or more than one BP. The proportional hazards model was used to investigate the correlation of ICTP baseline level with time to first SRE (TTSRE), TTP, and OS; and Poisson regression with the skeletal morbidity rate (SMR): number of SREs/person/year. Results: The median follow-up was 21 months. 81.9% patients had ICTP level above 6.2 μg/L and the mean value of ICTP was 15.1 (SD 11.9) μg/L. During the time period on study, 38% had PF, 57% had RT, and 9.5% had SCC. Median TTSRE was 20 months and the SMR was 0.84. Median TTP was 12 months and median OS time was 29 months. ICTP levels above 6.2 μg/L were associated with increased mortality risk (hazard ratio (HR) 2.86, 95%CI 1.37–6.00, p=0.005) and increased SMR (incidence rate ratio 1.88, 95%CI 0.98–3.60, p=0.057), but not with TTP (HR 1.18, 95%CI 0.67–2.07, p=0,57) or TTSRE (HR 1.59, 95%CI 0.82–3.08, p=0.17). Conclusions: Elevated serum ICTP levels is associated with decreased survival and increased incidence of SREs in BM patients on BP therapy.

No significant financial relationships to disclose.

Non-surgical treatment of peri-implant pathology

INTRODUCTION

Peri-implant pathologies consist of an inflammatory process affecting the soft and hard tissues surrounding the implants. Chlorhexidine is considered the gold standard antiseptic, with a large variety of choice in administration. In this study, a protocol for the irrigation of peri-implant pockets with a chlorhexidine gel, using a plastic needle for the delivery of the product into the peri-implant pockets is described.

STUDY PARTICIPANTS AND METHODS

Nine patients with at least one implant presenting peri-implant pathology (inflamed soft tissue associated with bone loss around the implant) were enrolled in this prospective clinical study, and followed-up for 1 year, where clinical parameters such as modified plaque index, modified bleeding index, probing pocket depths, attachment levels were assessed at baseline, 1 month, and 1 year after implementation of the treatment protocol.

RESULTS

Treatment success was achieved in eight of the nine patients (and in 11 of the 13 implants) according to the success criteria adopted by the authors of this study.

DISCUSSION

Infection control lies at the heart of peri-implant treatment. The control of three factors such as optimal diagnosis, removal of the aetiological factor of the disease (proper removal of debris and decontamination of the peri-implant sulcus/pocket) and a good patient's oral hygiene self-care represents the key to success, resulting in good treatment outcomes when managing peri-implant pathologies. The protocol used (irrigation of peri-implant pockets with chlorhexidine gel delivered by a plastic needle) is considered to be of utility.

Drug-induced home cage conspecifics' behavior can potentiate behavioral sensitization in mice

The effect of home cage conspecifics' behavior on locomotor sensitization to amphetamine (AMP) or ethanol (ETOH) were investigated. Female mice were repeatedly treated with saline or AMP (2.0 mg/kg for 13 days--Experiment 1) or saline or ETOH (1.8 g/kg for 21 days--Experiment 2) in home cages where all the animals had the same treatment (homogeneous home cages--HOM-HC) or in home cages where half of the animals were drug-treated and half of them were saline-treated (heterogeneous home cages--HET-HC). Behavioral sensitization was evaluated by the quantification of open-field locomotor activity after AMP or ETOH challenge injection, respectively. In both experiments, behavioral sensitization was potentiated in HOM-HC maintained animals. These results suggest that the behavioral sensitization phenomenon can be modified by home cage conspecifics' behavior.

Effects of morphine on the plus-maze discriminative avoidance task: role of state-dependent learning

RATIONALE

The amnesic effects of morphine may be related to its action on nociception, anxiety, or locomotion. This effect is also suggested to be related to state dependency.

OBJECTIVES

The aims of this study were to verify the effects of morphine on mice tested in the plus-maze discriminative avoidance task (DAT) that uses light and noise as aversive stimuli and allows the concomitant evaluation of learning, memory, anxiety, and locomotion and also to verify the possible role of state-dependent learning in the effects of morphine.

METHODS AND RESULTS

The DAT was conducted in a modified elevated plus-maze. In the training, the aversive stimuli were applied when mice entered in one of the enclosed arms, whereas in the test, no stimuli were applied. The main results showed that (1) pretraining morphine (5-20 mg/kg i.p.) induced retrieval deficits (evaluated by the time spent in the aversive arm in the test) but not acquisition deficits (evaluated by the decrease in aversive arm exploration along the training); (2) pretest morphine (5-10 but not 20 mg/kg) counteracted this deficit; (3) morphine induced hypolocomotion (decreased number of entries in the arms), irrespective of memory alterations; and (4) morphine did not alter anxiety-like behavior (evaluated by the time spent in the open arms) during the training.

CONCLUSIONS

Morphine given before training induces retrieval deficits in mice tested in the DAT, and these deficits could be related to morphine-induced state-dependent learning. Neither the memory deficit induced by pretraining morphine nor the reversal of this deficit by pretest morphine seems to be related to anxiety levels or locomotor alterations.