How does long-term drought acclimation modify structure-function relationships? A quantitative approach to leaf phenotypic plasticity of barley.

Under drought conditions the growth and survival of a plant depend on its adaptive characteristics and acclimation ability. Adaptation refers to inherent morpho-physiological characters providing protection against water losses. Acclimation, however, is a special case of phenotypic plasticity: environment-dependent phenotypic expression resulting to a 'new' phenotype through drought-induced modulations in leaf morphology, anatomy and physiology. Given that phenotypic plasticity influences environmental tolerance, a multi-trait plasticity index could be of great importance. Therefore, we examined the acclimation processes of three different barley genotypes using a multi-trait plasticity assessment with emphasis on the leaf water economy-related traits. Our results showed that (i) the structure-function co-ordination during long-term drought acclimation follows the trade-off between carbon gain and water saving as well as the competition between investments in photosynthesis vs synthesis of protective compounds; (ii) the genotypes with smaller leaf area, narrower and denser veins, as well as smaller and denser stomata i.e. traits providing tolerance, exhibited less drastic adjustments under stress conditions, suggesting a trade-off between acclimation and tolerance-adaptation; and (iii) the slope values of a multi-trait 'reaction norm' based on regression analysis of PCA scores were indicative of the degree of plasticity for each genotype, providing an accurate representation of a complex set of data with single numeric results easily comparable.

Local adoptive transfer of antitumor cellular immunity to xenogeneic animals studied with a rapid radioisotopic footpad assay.

The antitumor cellular immune response to Gross virus-induced rat tumor cells in F344 rats, as measured by a sensitive radioisotopic footpad assay, was adoptively transferred to syngeneic rats and to xenogeneic irradiated BALB/c mice. Xenogeneic transfer was accomplished by the injection of a mixture of rat tumor cells and syngeneic spleen cells, peritoneal exudate cells, or blood lymphocytes from specific immune rats into the footpads of mice. Peritoneal exudate cells produced the strongest footpad reaction in xenogeneic recipients. Use of the xenogeneic adoptive transfer system in a bioassay for human antitumor immunity appeared feasible.

Common tumor rejection antigens in methylcholanthrene-induced squamous cell carcinomas of mice detected by tumor protection and a radioisotopic footpad assay.

Seven transplantable lines of squamous cell carcinoma of the skin initiated in BALB/c mice by skin painting with methycholanthrene were systematically tested for cross-reactivity of their tumor rejection antigens in a 7 X 7 matrix. As determined by decreased tumor frequency after tumor cell challenge, each line was immunogenic against and/or immunosensitive to at least one and usually more than one of the other lines. A radioisotopic footpad assay for delayed hypersensitivity against viable tumor cells confirmed the cross-reactivity shown by tumor rejection. More than two antigens appeared to be present in the lines. Tests for C-type viruses were positive in all tumors; those for polyoma virus were negative. Whether the uniform presence of C-type viruses can account for the number and variety of antigens found, or whether the tumor rejection antigens are independent of virus expression, remains an open question. The finding of cross-reacting tumor rejection antigens in methylcholanthrene-induced squamous cell carcinomas encourages prospects for the development of more broadly applicable immunodiagnostic and immunotherapeutic reagents.

Accelerated regeneration of trypsin-treated surface antigens of simian virus 40-transformed BALB/3T3 cells induced by X-irradiation.

The antigens of SV40-transformed BALB/3T3 cells measured by a radioisotopic footpad assay after removal by trypsin treatment regenerated in vitro in 3 to 6 hr. After X-irradiation with 3000 R, however, the antigens were regenerated to normal levels within 1 h. X-ray doses of between 1000 and 5000 R accelerated the regeneration of cell surface antigens, while X-irradiation with the larger dose of 8000 R did not. X-irradiation of nontrypsinized tumor cells was without effect. Possible mechanisms of this phenomenon are discussed.

Reduced bone mineral density in patients with adult onset growth hormone deficiency.

We have demonstrated previously that adults with isolated GH deficiency of childhood onset have a reduced bone mineral density (BMD) of vertebral trabecular bone [quantitative computed tomography (QCT): median Z score -1.3, P < 0.01, n = 12] and of cortical bone in the forearm [single photon absorptiometry (SPA): median Z score -2.9, P = 0.001, n = 7]. We have now examined BMD in 26 patients (13 men, 13 women), aged between 23.6 and 59.5 (mean 42.4) yr, with adult onset GH deficiency, defined as a GH response of less than 5 micrograms/L to provocative testing, of at least two years duration. BMD was measured using QCT for vertebral trabecular bone, dual energy x-ray absorptiometry (DXA) in the lumbar spine and femoral neck, and SPA in the forearm. There was a highly significant reduction in QCT (median Z score -1.07, P < 0.00005), in DXA of the lumbar spine (median Z score -0.76, P = 0.0001) and in SPA of the forearm (median Z score -0.86, P = 0.0001) but not in DXA of the femoral neck (median Z score -0.38, P = 0.35). There were no significant differences in Z scores between those patients with isolated GH deficiency and those with GH and gonadotrophin deficiency. There was a significant positive correlation between age at which BMD was measured and Z score (the older the patient, the higher the Z score) for QCT (r = 0.38, P < 0.05) and SPA (r = 0.48, P < 0.01) with a trend to a positive correlation for DXA of the lumbar spine and femoral neck. Patients were grouped according to estimated duration of GH deficiency (less than 5 yr, n = 7; 5-10 yr, n = 10; greater than 10 yr, n = 9). These groups did not show a significant difference in BMD at any site. We conclude that patients with adult onset GH deficiency (isolated or in conjunction with other pituitary hormone deficiencies) have a reduced BMD. Age at development of GH deficiency may be more important than duration of GH deficiency in determining the degree of reduction in bone mass. The impact of GH treatment on BMD in adults with adult onset GH deficiency requires investigation.

Prognostic factors of gastric non-Hodgkin's lymphomas of the adult.

Sixteen patients, seven men and nine women, with a non-Hodgkin's lymphoma of the stomach (NHLS), have been managed in our institute during the past 15 years. Their median age was 68 years. Ten of them were classified, before treatment, at an early stage (I or II, Ann Arbor system) and six at an advanced one (III or IV). Ten patients were submitted to gastrectomy, and eight out of them had an adjuvant postoperative treatment (radiotherapy and/or chemotherapy). The remaining six patients were treated conservatively by radiotherapy and/or chemotherapy. Two patients that were followed less than 24 months were excluded from further study. In the remaining 14 patients, the 5-year actuarial and age-corrected survival rates were 42% +/- 28 and 53% +/- 35, respectively. In the gastrectomy subgroup, the corresponding rates were 77% +/- 22 and 93% +/- 24. The later ameliorated results also, reflect the effect of an earlier stage. The most important prognostic factors appeared to be the stage and the histologic type. Old age and female sex seem to predispose to a better outcome, but they are not independent prognostic factors. Finally, a bad nutritional status, at presentation, seems an ominous prognostic sign.

Replacement of the pyloric sphincter with the ileocecal valve: an experimental study.

BACKGROUND: Several surgical methods have been devised and applied to overcome the complications associated with the loss of the pyloric sphincter after distal gastrectomy. However, none of these methods creates an efficient sphincteric mechanism at the anastomotic site. The purpose of this experimental study in dogs was to replace the pylorus with the ileocecal valve and determine whether its sphincteric function would be preserved in its new location without affecting gastrointestinal motility and the health of the animals. METHODS: Thirteen dogs underwent surgical removal of the pyloric sphincter and a partial distal gastrectomy. The ileocecal valve, with a short segment of ileum, was then relocated so that the ileal segment was anastomosed to the stomach while the cecal segment was anastomosed to the duodenum. Intestinal continuity was reestablished by anastomosing the distal ileum with the ascending colon. Intraileal and intracolic pressures were measured in all animals prior to and following transposition of the ileocecal valve. In 3 of these animals, pre-pyloric (intragastric) and post-pyloric (intraduodenal) pressures were also measured before the pylorus was removed. Pressure measurements on both sides of the transposed ileocecal valve were performed again 4-6 months later. All pressure measurements were made directly with a water manometer. Radiographic and fluoroscopic studies were carried out on all animals to assess gastrointestinal motility, gastric emptying times, and the sphincteric competence of the transposed ileocecal valve. Hematological and biochemical studies intended to assess the nutritional status of all animals were carried out. Also, postoperative measurements were made of gastric basic acid output. RESULTS: All animals were alive and well 4-6 months after the initial operative procedure. Hematological studies and biochemical tests and studies of liver function remained normal. There was a slight reduction in serum B12 levels and, as expected, a significant postoperative reduction in gastric basic acid output. The intraluminal pressure measurements and the radiographic and fluoroscopic studies all showed that the sphincteric mechanism of the ileocecal valve was preserved in its new location, that gastrointestinal motility was not impaired, and that the healthy condition of the animals was maintained. Gross and histological examination of the transposed segments of the intestinal tract did not reveal any abnormalities. CONCLUSION: Because the anatomy and physiology of the human alimentary tract are similar to those of the dog, this technique may be applicable clinically, when indicated, to avoid and/or relieve complications resulting from gastrectomy, when those complications do not respond or have not responded to conservative management.

Latency measurement improvement of P100 complex in visual evoked potentials by FMH filters.

The ensemble average of Pattern Shift Visual Evoked Potentials (PSVEP) signals is seriously affected by random latency variations encountered in each individual sweep which is modeled as a continuous signal with linear segments and well-shaped triangular peaks. This effect is causing the smoothed peaks of the averaged PSVEP waveforms. It is our objective to restore the degraded peaks and provide accurate information about their exact location. The method used is based on nonlinear filtering of the FIR-Median Hybrid (FMH) type and is recommended as a postfiltering process to the well-known averaging methods of recovering PSVEP signals from noise by time-locking to stimuli. The new technique, tested in signals from clinical observations, has proven very promising.

Computed tomography in sternocostoclavicular hyperostosis.

Sternocostoclavicular hyperostosis is a rare but recognized entity characterized by new bone formation and ligamentous ossification which limits mobility of the sternoclavicular joints. Aetiology is obscure and debated. There may be considerable delay in establishing the diagnosis, even by specialists. In confirming the diagnosis plain radiography is of limited value but radionuclide bone scan and computed tomography (CT) may be helpful. Four cases are described to emphasize these points and illustrate the clinical and radiological features of the condition. High resolution CT with thin sections (5 mm or less) is the examination of choice for demonstrating the characteristic features and is essential if the condition is to be confirmed in its early stages when treatment might be more successful in delaying progression.

Coexistence of myelodysplastic syndrome and multiple myeloma.

We describe the simultaneous presentation of myelodysplastic syndrome (MDS) and multiple myeloma (MM). Our patient had MDS (RAEB type) and bone marrow infiltration (40% plasma cells), as well as biclonal paraprotein. Patients with MM, MDS have been reported after chemotherapy but few cases documenting the coexistence of MDS and MM at diagnosis have been reported in the literature.

A three-day octreotide-containing helicobacter pylori eradication therapy for cure of peptic ulcers.

BACKGROUND/AIMS: Octreotide is used to arrest peptic ulcer hemorrhage. Since it has anti-secretory properties, it could also be used in Helicobacter pylori eradication therapy, to cure peptic ulcer before discharging patients from hospital. The aim of this pilot study was to determine safety and efficacy of an ultra short quadruple octreotide containing H. pylori eradication therapy in patients with peptic ulcer. METHODOLOGY: Twenty-six consecutive symptomatic H. pylori-positive patients with duodenal (n = 20) or gastric ulcer (n = 6), were treated with a three-day course of octreotide 0.3 mg/day subcutaneously, amoxicillin plus metronidazole 2 g/day orally and colloid bismuth subcitrate 480 mg/day. CLO-test, culture and crush tissue smears were performed on admission to the study, at 4 and 8 weeks post treatment. The effect of octreotide on intragastric pH (n = 10) was also investigated. RESULTS: Octreotide significantly increased the mean 24-hour intragastric pH > 3 over 68.9% of the time (37.1%-99.5%). There were no treatment side effects. Ulcer pain was abolished at between 2-12 days. By intention-to-treat 24/26(92.3%, 95% CI 82%-100%) ulcers had healed at 4 weeks. H. pylori eradication rate at 8 weeks was 88.5% (23/26) (95% CI 76%-100%). CONCLUSIONS: Our ultra-short octreotide containing quadruple therapy is a safe and effective regime in eradicating H. pylori and healing peptic ulcers. It may be a suitable therapy for hospitalized patients with peptic ulcer hemorrhage.

A new concept toward computer-aided medical diagnosis--a prototype implementation addressing pulmonary diseases.

The original concept that led to the structuring of a computer-based medical decision support system (DSS) that is able to support a physician's diagnosis is introduced in this paper. The concept's implementation modeled a generic DSS, the core of which are an integrated knowledge/information base (KIB) along with the inference properties of a data evaluator. The KIB encapsulates the necessary medical knowledge and experience in the form of rules and constraints, preemptive tasks, and actual patients' clinical data. The data evaluator handles approved medical subjective and objective criteria for assessing the KIB's data. The data evaluator incorporates a medical standard data gathering and decision process, structured upon the principles of the clinical differential diagnosis methodology and has been integrated in the system by means of both algorithmic and artificial intelligence techniques. The novel model and the resulted computer-based package have been extensively tested under the Pulmonary Department, University Regional Hospital Patras, Patras, Greece.

OTE-TS--a new value-added telematics service for telemedicine applications.

A new telemedicine service denoted as the Hellenic Telecommunication Organization Telemedicine Service (OTE-TS), which addresses an open multidisciplinary group of medical care providers (users), is presented in this paper. OTE-TS is supported by the Hellenic Telecommunication Organization (OTE) and is the result of the close collaboration of engineers, medical doctors, and market analysts. Its architecture provides the user with an integrated electronic working domain handling diverse types of conversational audiovisual information and medical records. It includes a stack of functions, protocols, and interfaces for data acquisition, processing, and display, and for the composition of dial-up multiparty cooperation schemes (synchronous or asynchronous), suitable for the coordination and management of high-level consult, report, and review activities. The service provider (i.e., the OTE) performs the central administration and maintenance of the service, as well as the management of medical cases and reports that are exchanged among the users. The service has been extensively tested in real-world conditions.

Tuberculosis of the prostate.

We present five cases of tuberculous prostatitis. In all cases this was an incidental histologic finding after transurethral prostatectomy. The patients were all treated with an antituberculous drug regimen. A literature review of this rare condition is included.

Intraoperative electron beam radiotherapy followed by moderate doses of external beam radiotherapy in the treatment of resected soft tissue sarcomas of the extremities.

PURPOSE: Soft tissue sarcomas (STS) have a high incidence of local recurrence. In an effort to improve the local control rate and the survival in patients with STS, treatment strategies employing intraoperative electron beam radiotherapy (IOERT) in combination with external beam radiotherapy (EBRT) and extensive surgical resection have been explored. This study assesses the rate of overall survival (OS), local control and toxicity of this multimodal approach for primary and recurrent STS of the extremities. PATIENTS AND METHODS: From 1999 to 2004, 36 patients were treated at Agios Savvas Cancer Hospital for primary or recurrent extremity STS with IOERT as a component of their treatment. All patients underwent surgical resection, IOERT, and most of them received postoperative EBRT with a median dose of 45 Gy. Chemotherapy was given to patients with high grade tumors. Thirteen patients were treated for primary disease and 23 for isolated local recurrence.The locations of the tumors were as follows: upper limbs n=19, lower limbs n=17. Tumor size was >5 cm in 16 (44%) patients and high-grade histology (II-III) was present in 24 (67%) patients. Six (17%) patients had positive surgical margins. RESULTS: With a median follow up of 24 months (range 6-48) OS was 72% (84.5% for patients with low grade lesions compared to 65% for high grade lesions, p=0.127, and 90% for tumors <5 cm compared to 50% for tumors >5 cm, p=0.0136). Overall local tumor control rate was 89% (92% in primary disease group versus 87% in isolated local recurrence group, p=0.136, and 93% for patients with negative surgical margins versus 67% for those with positive margins, p=0.0013). Distant metastases occurred in 10 patients (1 of 13 (8%) with primary disease, and 9 of 23 (39%) with isolated local recurrence). All distant metastases were to the lungs. Twelve (33%) patients developed moderate neurotoxicity. CONCLUSION: In selected patients, IOERT results in excellent local control and OS with acceptable toxicity.

Analyzing functional brain connectivity by means of commute times: a new approach and its application to track event-related dynamics.

There is growing interest in studying the association of functional connectivity patterns with particular cognitive tasks. The ability of graphs to encapsulate relational data has been exploited in many related studies, where functional networks (sketched by different neural synchrony estimators) are characterized by a rich repertoire of graph-related metrics. We introduce commute times (CTs) as an alternative way to capture the true interplay between the nodes of a functional connectivity graph (FCG). CT is a measure of the time taken for a random walk to setout and return between a pair of nodes on a graph. Its computation is considered here as a robust and accurate integration, over the FCG, of the individual pairwise measurements of functional coupling. To demonstrate the benefits from our approach, we attempted the characterization of time evolving connectivity patterns derived from EEG signals recorded while the subject was engaged in an eye-movement task. With respect to standard ways, which are currently employed to characterize connectivity, an improved detection of event-related dynamical changes is noticeable. CTs appear to be a promising technique for deriving temporal fingerprints of the brain's dynamic functional organization.

Multiple brown tumors of the ribs simulating malignancy.

Bone disease associated with primary hyperparathyroidism, known as osteitis fibrosa cystica, is now very rarely encountered, since the parathyroid disorder is most often diagnosed at the early stage of asymptomatic hypercalcemia. Here, we report the case of a patient with multiple pleural-based masses and hypercalcemia, which led to the presumptive diagnosis of malignancy. However, histological and laboratory data were consistent with the development of brown tumors of the ribs due to underlying severe hyperparathyroidism.

Administration of high doses of recombinant human erythropoietin to patients with beta-thalassemia intermedia: a preliminary trial.

Four patients (1 male, 3 female, age range 16-56 yr) with beta-thalassemia intermedia were given high doses of recombinant human erythropoietin (rHuEpo), iron sulfate and folic acid in an attempt to improve their anemia. The dose schedule was: rHuEpo, 500 U/kg 3 times weekly, iron sulfate, 300 mg/d and folic acid, 5 mg/d. All patients were red blood cell transfusion-dependent. Hematological data and fetal hemoglobin (HbF) were assayed every 2 wk. XmnI polymorphism and beta-thalassemia mutations were identified by PCR. All patients showed a moderate to high increase in hemoglobin values (mean value: 2.5 g/dl) and in 1 patient HbF levels also increased; 3 patients became red blood cell transfusion-independent and 1 patient was able to extend the intervals between transfusions significantly. No side effects were observed during rHuEpo therapy.

A cross-over comparison of the effect of morphine, pethidine, pentazocine, and phenazocine on biliary pressure.

The effects on biliary pressure of pentazocine, morphine, pethidine, and phenazocine were compared by direct measurement through a ;T' tube after choledochotomy. In two within-patient comparisons, the mean increases in biliary pressure following intramuscular morphine were significantly greater than those following pentazocine. When pethidine and phenazocine were compared with pentazocine, the mean increases were lower following pentazocine but not to a statistically significant extent. Pentazocine appears to be the most appropriate strong analgesic in biliary and pancreatic disease.