Towards more adequate colour histograms for in-body images

Although there is a growing number of scientific papers describing classification of in-body images, most of it is based on traditional colour histograms. In this paper we explain why these might not be the most adequate visual features for in-body image classification. Based on a colour dynamic range maximization criterion, we propose a methodology for creating more adequate colour histograms, testing it on a vital-stained magnification endoscopy scenario.

Evaluation of exposure parameters in plain radiography: a comparative study with European guidelines

Typical distribution of exposure parameters in plain radiography is unknown in Portugal. This study aims to identify exposure parameters that are being used in plain radiography in the Lisbon area and to compare the collected data with European references [Commission of European Communities (CEC) guidelines]. The results show that in four examinations (skull, chest, lumbar spine and pelvis), there is a strong tendency of using exposure times above the European recommendation. The X-ray tube potential values (in kV) are below the recommended values from CEC guidelines. This study shows that at a local level (Lisbon region), radiographic practice does not comply with CEC guidelines concerning exposure techniques. Further national/local studies are recommended with the objective to improve exposure optimisation and technical procedures in plain radiography. This study also suggests the need to establish national/local diagnostic reference levels and to proceed to effective measurements for exposure optimisation.

Leishmaniosis--a report about the microvascular and cellular architecture of the infected spleen in Canis familiaris

Leishmaniosis is an anthropozoonosis caused by an intracellular protozoan parasite that causes a wide spectrum of diseases in humans and dogs worldwide. In the Mediterranean basin, Portugal, Central and South America, and in the Middle East, visceral leishmaniosis is caused by Leishmania infantum. In these areas, dogs are believed to be the natural reservoirs of this parasite. In the case of visceral leishmaniosis, the spleen is one of the several hematopoietic and immunocompetent organs involved. Since this viscera is a blood filter, the authors investigated the expression of the morphological and microvascular environment and modifications of the spleen cell population related to immunological responses to this parasitic condition. The tools used to perform this study were scanning electronic microscopy of intact tissue and corrosion casts, transmission electronic microscopy, histology and immunohistochemistry. The results reveal three important modifications concerning the spleen's microvascular architecture when compared with its normal pattern, independently of the serological titer obtained with indirect immunofluorescence. (1) A marked scarcity of the sinusoidal system sheet that surrounds the central artery/arteriole of the white pulp; (2) A huge development of pulp venules and veins; (3) The presence of a surprising development of reticular fibers. The authors postulate that independent of the virulence of the parasite involved and the type of immunity prevalent in a particular host, the spleen develops blood dynamic conditions that permit reduction in the speed of blood flow so that cells involved in immunological processes can proliferate and differentiate, and also contributes to trapping lymphocytes within the area through the differentiation of characteristics that resemble those of HEV endothelial cells.

Seizures in cerebral vein and dural sinus thrombosis

To describe early symptomatic and late seizures in a cohort of patients with acute cerebral vein and dural sinus thrombosis (CVDST) and to identify their determinants, we performed a prospective registry and follow-up study of CVDST patients admitted to 20 Portuguese hospitals, from June 1995 to June 1998. Of 91 registered patients, 31 (34%) had early symptomatic seizures; 29 (31.9%) as a presenting feature and 2 (2.1%) after admission. Early symptomatic seizures were more frequent in patients with motor and sensory deficits and in those with focal oedema/ischaemic infarcts or haemorrhages on admission CT/MR. On multivariate logistic regression analysis, sensory defects (OR = 7.8; 95% CI = 0.8-74.8) and a parenchymal lesion on admission CT/MR (OR = 3.7, 95% CI = 1.4-9.4) were found to be significant predictors of early symptomatic seizures. Seizures were directly related to acute death in 2 patients. Eight (9.5%) patients had late seizures, which were multiple in 4 (4.8%). Late seizures were more frequent in patients with early symptomatic seizures and with haemorrhage on admission CT/MR. Neither early symptomatic seizures nor late seizures were related to functional prognosis at the last follow-up (median = 1 year). There is a moderate risk of seizure recurrence early in the course and during the first year after CVDST. Seizures can be a cause of acute death, but might not have an independent influence on functional outcome. Pharmacological prevention of seizures after CVDST should probably be limited to patients with early symptomatic seizures and cerebral lesions on admission CT/MR.

Polar localization of filamentous actin in cells of the scale-forming alga Pleurochrysis sp

Filamentous actin localized to polar cytoplasmic areas between chloroplasts of the prymnesiophyte Pleurochrysis sp. Phalloidin staining of cells, confocal laser scanning microscopy, and previous electron microscopy (E. K. Hawkins and J. J. Lee, Protoplasma 216: 227-238, 2001) indicate that the location of phalloidin staining coincides with the cellular location of the Golgi apparatus. The results are consistent with the hypothesis that filamentous actin may be involved in biogenesis and polarized secretion of scales.

A leptin-sympathetic-leptin feedback loop: potential implications for regulation of arterial pressure and body fat

AIM

This manuscript briefly reviews evidence and potential implications of a leptin-sympathetic-leptin feedback loop.

RESULTS

Leptin increases sympathetic nerve activity to brown adipose tissue, kidney and other tissues. This action has implications for regulation of arterial pressure. In turn, there is evidence that sympathoadrenal stimulation inhibits leptin mRNA expression and secretion from white adipose tissue through beta adrenergic mechanisms.

CONCLUSION

This sympathetic modulation of leptin expression has potential implications for regulation of body fat.

Cerebral vein and dural sinus thrombosis in Portugal: 1980-1998

There is insufficient information on the prognosis and safety of anticoagulation in acute cerebral vein and dural sinus thrombosis (CVDST). To describe the clinical aspects and medical management of CVDST in Portuguese hospitals, to evaluate the safety of anticoagulation in this setting, and to identify subgroups of CVDST patients with different prognoses, we registered symptomatic CVDST patients admitted to Portuguese hospitals since 1980. Cases were collected from file review up to 6/95 and from consecutively admitted patients from 6/95 to 6/98. One hundred and forty-two patients were included from 20 centers (51 retrospectively and 91 prospectively). One hundred and twelve patients (79%) were anticoagulated. There were only 6 new intracranial hemorrhages (4 in anticoagulated patients) and 2 systemic hemorrhages. Nine (6%) patients died. At discharge, 96 (68%), had recovered completely and only 6 (4%) were dependent (Rankin > or = 3). Significant multivariate predictors of death/dependency were central nervous system infection as a predisposing cause (odds ratio, OR = 15.4; 95% confidence interval CI = 111-1.1), encephalopathy on admission (OR = 5.2; 95% CI = 18.7-1.5) and hemorrhage on admission CT/MR (OR = 3.6; 95% CI = 12.9-1). Significant predictors of complete recovery were no encephalopathy on admission (OR = 5; 95% CI = 12.5-2.1), age < 45 years (OR = 3.8; 95% CI = 9.2-1.6) and anticoagulation (OR = 3.8; 95% CI = 9.6-1.5). It is possible to identify CVDST patients with potential bad or good prognosis in the acute phase. Anticoagulation was safe and a predictor of complete recovery in acute CVDST.

Hepatic arterial infusion of cisplatin diluted in hypotonic 25 g/l glucose solution administered in balloon-occluded hepatic artery: experimental rationale and clinical pilot study

Reduced osmolarity in incubation medium was previously shown to increase in vitro cellular accumulation and cytotoxicity of cisplatin on cancer cells. We confirmed in the present work that cisplatin diluted in an hypotonic 25 g/l glucose solution (124 mOsm) was dramatically more cytotoxic in vitro than cisplatin diluted in normotonic 9 g/l NaCl (300 mOsm) on the human HT29 colon and MCF7 breast cancer cells. We conducted then a pilot clinical study on the administration of cisplatin diluted in hypotonic 25 g/l glucose solution given through the balloon-occluded hepatic artery for the treatment of liver metastases from colon or breast cancer tumors. Nine patients (5 men, 4 women; mean age 58, range: 44-71) with confirmed isolated, unresectable metastases from colorectal (7) or breast (2) tumors were included in this study and a total of 23 cycles were administered (2.55 per patient; range 1-5) with an average dose of 50 mg cisplatin (range: 12.5-100). Hepatic artery dissection due to balloon injury with partial or complete arterial obstruction were encountered in 2 patients. Pain in the liver and epigastric area was the main symptom which was constant and intense during the IAH cisplatin injection. Fever > 38 degrees C was observed in 15/23 cycles and increase of creatinine in 1/23 cycles. Transient increase of hepatic transaminases without change in prothrombin time was registered in all patients. However one patient who received the highest dose of 100 mg cisplatin developed a persistent but reversible clinical jaundice and a transient increase in prothrombin time. One patient achieved a partial response (12 weeks), 7 had stable disease (mean duration: 6 weeks) and one had a progressive disease. Hepatic arterial infusion of cisplatin diluted in hypotonic 25 g/l glucose solution and administered through the balloon-occluded hepatic artery is a feasible approach. Total dose of cisplatin in hypotonic glucose solution will not exceed 80 mg by cure in a further phase II study.

[Prognosis of mitral commissurotomy. Study of 1134 mitral patients 20 years later]

With a test sample (n = 323), consisting of the answers to an inquiry about the patients with operated mitral stenosis (n = 1134), between 1952 and 1978, in "Hospital Pulido Valente", Lisbon, we compared the group of survivors with the decreased in the relation to sex, age, valvular lesion, type of surgery, valvular area before and after surgery and existence of incompetence. We concluded that mitral stenosis was more frequent in females (4/1), but it had a worse prognosis in males. The lower the age at the time of surgery the better long time prognosis. Digital and instrumental valvulotomy had similar mortality. Valvular incompetence had a worse prognosis and is associated with larger valvular area.

Development of a SPME-GC-ECD methodology for selected pesticides in must and wine samples

A method for the determination of some pesticide residues in must and wine samples was developed using solid-phase microextraction (SPME) and gas chromatography-electron capture detection (GC/ECD). The procedure only needs dilution as sample pre-treatment and is therefore simple, fast and solvent-free. Eight fungicides (vinclozolin, procymidone, iprodione, penconazole, fenarimol, folpet, nuarimol and hexaconazole), one insecticide (chlorpyriphos) and two acaricides (bromopropylate and tetradifon) can be quantified. Good linearity was observed for all the compounds in the range 5-100 microg/L. The reproducibility of the measurements was found acceptable (with RSD's below 20%). Detection limits of 11 microg/L, on average, are sufficiently below the proposed maximum residue limits (MRL's) for these compounds in wine. The analytical method was applied to the determination of these compounds in Portuguese must and wine samples from the Demarcated Region of Alentejo, where any residues could be detected.

Study on COgnition and Prognosis in the Elderly (SCOPE): baseline characteristics

The Study on COgnition and Prognosis in the Elderly (SCOPE) is a multi-centre, prospective, randomized, double-blind, parallel-group study. The primary objective of SCOPE is to assess the effect of the angiotensin II type 1 (AT1) receptor blocker, candesartan cilexetil 8-16 mg once daily, on major cardiovascular events in elderly patients (70-89 years of age) with mild hypertension (DBP 90-99 and/or SBP 160-179 mmHg). The secondary objectives of the study are to test the hypothesis that antihypertensive therapy can prevent cognitive decline (as measured by the Mini Mental State Examination, MMSE) and dementia, and to assess the effect of therapy on total mortality, myocardial infarction (MI), stroke, renal function, and hospitalization. A total of 4964 patients from 15 participating countries were recruited during the randomization phase of SCOPE, exceeding the target population of 4000. The mean age of the patients at enrolment was 76 years, the ratio of male to female patients was approximately 1:2, and 52% of patients were already being treated with an antihypertensive agent at enrolment. The majority of patients (88%) were educated to at least primary school level. At randomization, mean sitting blood pressure values were SBP 166 mmHg and DBP 90 mmHg, and the mean MMSE score was 28. Previous cardiovascular disease in the study population included myocardial infarction (4%), stroke (4%) and atrial fibrillation (4%). Men, more often than women, had a history of previous MI, stroke and atrial fibrillation. A greater percentage of men were smokers (13% vs 6% in women) and had attended university (11% vs 3% of women). Of the randomized patients, 21% were 80 years of age. In this age group smoking was less common (4% vs 10% for 70-79-year-olds) and fewer had attended university (4% vs 7% for 70-79-year-olds). The incidence of MI was similar in both age groups. However, stroke and atrial fibrillation had occurred approximately twice as frequently in the older patients. The patients' mean age at baseline was similar in the participating countries, and most countries showed the approximate 1:2 ratio for male to female patients. There was also little inter-country variation in terms of mean SBP, DBP or MMSE score. However, there was considerable regional variation in the percentage of patients on therapy prior to enrolment.

Multi-residue methodology for pesticide screening in wines

A multi-residue solid-phase microextraction/gas chromatography/electron-capture detection method for pesticide screening (nine organochlorine, eleven organophosphorous and a tiadiazine insecticides, a benzoylurea acaricide and a halogenated sulfamide fungicide) in wine was developed. Fiber coating, extraction time and temperature, exposure of the fiber to the headspace or to the liquid phase and the ethanol effect on pesticides extraction were the parameters studied. The best results were obtained for a 100 microm poly(dimethylsiloxane) fiber, with 30 min immersion, in a 3 ml sample, at 45 degrees C. Pesticides extraction yield from aqueous spiked solutions was studied, for different ethanol concentrations (9%, 12.5% and 20%, v/v), which are representative of the main types of Portuguese wines. Calibration curves for extracted standards gave linear responses for all the pesticides, except dichlorvos, mevinphos, disulfoton and methidathion. Average detection limits were lower than 5 ppb and no significant interference from the matrix was found in the conditions studied, except for buprofezin.

Molecular typing and exopolysaccharide biosynthesis of Burkholderia cepacia isolates from a Portuguese cystic fibrosis center

This work describes the first epidemiological survey of Burkholderia cepacia involved in pulmonary infections among the Portuguese population with cystic fibrosis (CF) who attended the major CF treatment Center in Lisbon at Sta. Maria Hospital from 1995 to the end of 1997. The characterization of the genomic relatedness of the isolates was based on the analysis of their ribopatterns (with EcoRI) followed by construction of a ribotype-based phylogenetic tree. This study was complemented with macrorestriction fragment analysis by pulsed-field gel electrophoresis. After optimization of the solid growth medium, we found that exopolysaccharide (EPS) production by B. cepacia CF isolates is not as rare a phenomenon as was thought before; indeed, 70% of the isolates examined were EPS producers.

Cooling therapy for acute stroke

BACKGROUND

Recent studies in acute stroke patients have shown an association between body temperature and prognosis.

OBJECTIVES

Our objective was to assess the effects of cooling when applied to patients with acute ischaemic stroke or primary intracerebral haemorrhage.

SEARCH STRATEGY

We searched the Cochrane Stroke Group's trial register (last searched in March 1999), plus MEDLINE searched up to November 1998 and EMBASE searched from January 1980 to November 1998. We contacted investigators, pharmaceutical companies and manufacturers of cooling equipment in this field.

SELECTION CRITERIA

All completed randomised controlled trials or controlled clinical trials, published or unpublished, where cooling therapy (therapy given by physical devices or antipyretic drugs primarily to lower body temperature independently of basal temperature at the beginning of treatment) was applied up to two weeks of an acute ischaemic stroke or primary intracerebral haemorrhage.

DATA COLLECTION AND ANALYSIS

Two reviewers independently searched for relevant trials.

MAIN RESULTS

No randomised trials or controlled trials were identified; one placebo-controlled trial of metamizol is currently underway.

REVIEWER'S CONCLUSIONS

There is currently no evidence from randomised trials to support the routine use of physical or chemical cooling therapy in acute stroke. Since experimental studies showed a neuroprotective effect of hypothermia in cerebral ischaemia, and hypothermia appears to improve the outcome in patients with severe closed head injury, trials with cooling therapy in acute stroke are warranted.

A new major triterpene saponin from the roots of Cucurbita foetidissima

Foetidissimoside B (1), a novel triterpene saponin, was isolated from the roots of Cucurbita foetidissima. Based on spectroscopic data, especially direct and long-range heteronuclear 2D NMR analysis and on chemical transformations, the structure of 1 was elucidated as 3-O-beta-D-glucuronopyranosyl-echinocystic acid 28-O-beta-D-glucopyranosyl-(1-->3)-beta-D-xylopyranosyl(1-->3)-[beta- D-xylopyranosyl (1-->4)]-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside . Compound 1 did not show any ability to potentiate in vitro cisplatin cytotoxicity in a human colon cancer cell line.

Study on COgnition and Prognosis in the Elderly (SCOPE)

The Study on COgnition and Prognosis in the Elderly (SCOPE) is a multicentre, prospective, randomized, double-blind, parallel-group study designed to compare the effects of candesartan cilexetil and placebo in elderly patients with mild hypertension. The primary objective of the study is to assess the effect of candesartan cilexetil on major cardiovascular events. The secondary objectives of the study are to assess the effect of candesartan cilexetil on cognitive function and on total mortality, cardiovascular mortality, myocardial infarction, stroke, renal function, hospitalization, quality of life and health economics. Male and female patients aged between 70 and 89 years, with a sitting systolic blood pressure (SBP) of 160-179 mmHg and/or diastolic blood pressure (DBP) of 90-99 mmHg, and a Mini-Mental State Examination (MMSE) score of 24 or above, are eligible for the study. The overall target study population is 4000 patients, at least 1000 of whom are also to be assessed for quality of life and health economics data. After an open run-in period lasting 1-3 months, during which patients are assessed for eligibility and those who are already on antihypertensive therapy at enrolment are switched to hydrochlorothiazide 12.5 mg o.d., patients are randomized to receive either candesartan cilexetil 8 mg once daily (o.d.) or matching placebo o.d. At subsequent study visits, if SBP remains >160 mmHg, or has decreased by <10 mmHg since the randomization visit, or DBP is >85 mmHg, study treatment is doubled to candesartan cilexetil 16 mg o.d. or two placebo tablets o.d. Recruitment was completed in January 1999. At that time 4964 patients had been randomized. All randomized patients will be followed for an additional 2 years. If the event rate is lower than anticipated, the follow-up will be prolonged.

Epinephrine enhances penetration and anti-cancer activity of local cisplatin on rat sub-cutaneous and peritoneal tumors

Despite the theoretical advantages of a high local concentration of anti-cancer drugs, local chemotherapy often fails to produce complete and lasting responses in experimental and human solid tumors. Experiments using Patent Blue dye showed that fluids diffused poorly into tumor mass when injected inside or around s.c. rat tumors in rats. In the same way, Patent Blue dye distributed poorly from the peritoneal cavity into the tumor nodules of rats with peritoneal carcinomatosis. The potent vasoconstrictor, epinephrine (1 mg/kg of body weight) was shown to facilitate the penetration of Patent Blue dye into s.c. and peritoneal rat tumors. Platinum concentration evaluated by micro-PIXE in s.c. DHD/K12/ PROb colon tumors or by atomic absorption spectrometry in DHD/K12/PROb peritoneal tumors was 4- to 12-fold higher when epinephrine was added to local cisplatin. Peri-tumoral or intra-tumoral injection of cisplatin (2 mg/kg) alone does not cure s.c. DHD/K12/PROb colon tumors or GV1A1 glioma tumors in BD IX rats. By contrast, a complete and lasting cure of s.c. tumors was achieved regularly and without skin necrosis when epinephrine was added to intra-tumoral or peri-tumoral cisplatin. Rats with peritoneal-tumor nodules 1 to 2 mm in diameter, and insensitive to i.p. cisplatin alone, were cured when the anti-cancer drug was combined with epinephrine. These experimental results could justify clinical trials using a combination of cisplatin and epinephrine in the treatment of locally growing solid tumors.