Peto's "Paradox" and Six Degrees of Cancer Prevalence

Peto's paradox and the epidemiologic observation of the average six degrees of tumor prevalence are studied and hypothetically solved. A simple consideration, Petho's paradox challenges our intuitive understanding of cancer risk and prevalence. Our simple consideration is that the more a cell divides, the higher the chance of acquiring cancerous mutations, and so the larger or longer-lived organisms have more cells and undergo more cell divisions over their lifetime, expecting to have a higher risk of developing cancer. Paradoxically, it is not supported by the observations. The allometric scaling of species could answer the Peto paradox. Another paradoxical human epidemiology observation in six average mutations is necessary for cancer prevalence, despite the random expectations of the tumor causes. To solve this challenge, game theory could be applied. The inherited and random DNA mutations in the replication process nonlinearly drive cancer development. The statistical variance concept does not reasonably describe tumor development. Instead, the Darwinian natural selection principle is applied. The mutations in the healthy organism's cellular population can serve the species' evolutionary adaptation by the selective pressure of the circumstances. Still, some cells collect multiple uncorrected mutations, adapt to the extreme stress in the stromal environment, and develop subclinical phases of cancer in the individual. This process needs extensive subsequent DNA replications to heritage and collect additional mutations, which are only marginal alone. Still, together, they are preparing for the first stage of the precancerous condition. In the second stage, when one of the caretaker genes is accidentally mutated, the caused genetic instability prepares the cell to fight for its survival and avoid apoptosis. This can be described as a competitive game. In the third stage, the precancerous cell develops uncontrolled proliferation with the damaged gatekeeper gene and forces the new game strategy with binary cooperation with stromal cells for alimentation. In the fourth stage, the starving conditions cause a game change again, starting a cooperative game, where the malignant cells cooperate and force the cooperation of the stromal host, too. In the fifth stage, the resetting of homeostasis finishes the subclinical stage, and in the fifth stage, the clinical phase starts. The prevention of the development of mutated cells is more complex than averting exposure to mutagens from the environment throughout the organism's lifetime. Mutagenic exposure can increase the otherwise random imperfect DNA reproduction, increasing the likelihood of cancer development, but mutations exist. Toxic exposure is more challenging; it may select the tolerant cells on this particular toxic stress, so these mutations have more facility to avoid apoptosis in otherwise collected random mutational states.

A Potential Bioelectromagnetic Method to Slow Down the Progression and Prevent the Development of Ultimate Pulmonary Fibrosis by COVID-19

Introduction

Right now, we are facing a global pandemic caused by the coronavirus SARS-CoV-2 that causes the highly contagious human disease COVID-19. The number of COVID-19 cases is increasing at an alarming rate, more and more people suffer from it, and the death toll is on the rise since December 2019, when COVID-19 has presumably appeared. We need an urgent solution for the prevention, treatment, and recovery of the involved patients.

Methods

Modulated electro-hyperthermia (mEHT) is known as an immuno-supportive therapy in oncology. Our proposal is to apply this method to prevent the progression of the disease after its identification, to provide treatment when necessary, and deliver rehabilitation to diminish the fibrotic-often fatal-consequences of the infection.

Hypothesis

The effects of mEHT, which are proven for oncological applications, could be utilized for the inactivation of the virus or for treating the fibrotic consequences. The hypothesized mEHT effects, which could have a role in the antiviral treatment, it could be applied for viral-specific immune-activation and for anti-fibrotic treatments.

Quo Vadis Oncological Hyperthermia (2020)?

Heating as a medical intervention in cancer treatment is an ancient approach, but effective deep heating techniques are lacking in modern practice. The use of electromagnetic interactions has enabled the development of more reliable local-regional hyperthermia (LRHT) techniques whole-body hyperthermia (WBH) techniques. Contrary to the relatively simple physical-physiological concepts behind hyperthermia, its development was not steady, and it has gone through periods of failures and renewals with mixed views on the benefits of heating seen in the medical community over the decades. In this review we study in detail the various techniques currently available and describe challenges and trends of oncological hyperthermia from a new perspective. Our aim is to describe what we believe to be a new and effective approach to oncologic hyperthermia, and a change in the paradigm of dosing. Physiological limits restrict the application of WBH which has moved toward the mild temperature range, targeting immune support. LRHT does not have a temperature limit in the tumor (which can be burned out in extreme conditions) but a trend has started toward milder temperatures with immune-oriented goals, developing toward immune modulation, and especially toward tumor-specific immune reactions by which LRHT seeks to target the malignancy systemically. The emerging research of bystander and abscopal effects, in both laboratory investigations and clinical applications, has been intensified. Our present review summarizes the methods and results, and discusses the trends of hyperthermia in oncology.

Abstract 422: Lymph node metastasis evolution drives immune evasion and targeted therapy resistance in gastro-esophageal adenocarcinomas (GEAs)

GEAs are aggressive tumors in which several targeted therapy trials have failed. We assessed intratumor heterogeneity (ITH) and its impact on progression and therapy failure by applying an 81-gene NGS panel and SNP array copy number aberration (CNA) analysis to multiple primary tumor (T) regions and lymph node (LN) metastases from 9 GEAs.

Analysis of 39 samples found ITH in all cases. 8 chromosomally instable (CIN) GEAs predominantly evolved through CNAs, with 17-76% of the genome affected by heterogeneous CNAs. A microsatellite instable GEA showed parallel evolution and diversified exclusively through point mutations (58% ITH). This demonstrates ongoing genomic instability rather than punctuated evolution and that specific instability mechanisms impact evolutionary trajectories.

LN metastases contributed more to ITH (p<0.01) than any anatomic location within T. Further, subclonal aberrations that activate the Mitogen Activated Protein Kinase-pathway (MAPK-pw), including ERBB3, ERK2, KRAS and NRAS amplifications (amp) and NRAS mutations, were detected in LN metastases from 4/8 CIN GEAs. Subclonal MAPK-activating amp were enriched in LN (p=0.019) compared to T regions that only exhibited a single subclonal MET amp. Convergent evolution of LN subclones across several GEAs suggests that selection pressures differ systematically between LN and T ecosystems.

To assess the phenotypes established by MAPK-activating amp evolution, we analyzed 135 published primary CIN subtype GEAs. Cytolytic activity (CYT), estimating tumor immune recognition from RNA expression data, correlated with the mutation load in GEAs with EGFR, ERBB2 or MET amp (p=0.04). In contrast, CYT did not correlate with mutation load in GEAs with KRAS or ERBB3 amp (p=0.22, NRAS/ERK2: insufficient data), indicating that these specific alterations, that also recurrently evolved in LN, may enable immune evasion. Downregulation of TAP and Class I MHC genes (p<0.05) in KRAS or ERBB3 amp GEAs suggested impaired antigen processing and presentation as the mechanisms driving T cell immune evasion.

Moreover, ITH of MAPK-activating amp is likely to confer resistance to upstream tyrosine kinase inhibition. We used GEA cell lines with various MAPK-activating amp (ERBB2, MET, NRAS) to investigate downstream MAPK-pw inhibition as a novel strategy to broadly target heterogeneous subclones. Growth control was incomplete with ERK- and MEK-inhibitors but the panRAF/SRC inhibitor CCT196969 was effective in all lines, suggesting that it can effectively intercept subclonal heterogeneity in GEAs.

In conclusion, we identified ITH with parallel and convergent evolution in 9/9 metastatic GEAs. Distinct selection pressures in LN foster the evolution of subclonal MAPK-activating amp that decrease immunogenicity and drive evolutionary pre-adaptation to future targeted drugs that can be intercepted by panRAF/SRC inhibitors.

Citation Format: Matthew N. Davies, Louise J. Barber, Georgia Spain, Filipa Lopes, Katharina von Loga, Beatrice Griffiths, Andrew Woolston, Donat Alpar, Marta Gomez, Kamil A. Lipinski, Kerry Fenwick, Zakaria Eltahir, Stefano Lise, Emese I. Agoston, Laszlo Harsanyi, Richard Marais, Andrew Wotherspoon, A Szasz, Caroline Springer, Marco Gerlinger. Lymph node metastasis evolution drives immune evasion and targeted therapy resistance in gastro-esophageal adenocarcinomas (GEAs) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 422. doi:10.1158/1538-7445.AM2017-422

Improving immunological tumor microenvironment using electro-hyperthermia followed by dendritic cell immunotherapy

Background

The treatment of intratumoral dentritic cells (DCs) commonly fails because it cannot evoke immunity in a poor tumor microenvironment (TME). Modulated electro-hyperthermia (mEHT, trade-name: oncothermia) represents a significant technological advancement in the hyperthermia field, allowing the autofocusing of electromagnetic power on a cell membrane to generate massive apoptosis. This approach turns local immunogenic cancer cell death (apoptosis) into a systemic anti-tumor immune response and may be implemented by treatment with intratumoral DCs.

Methods

The CT26 murine colorectal cancer model was used in this investigation. The inhibition of growth of the tumor and the systemic anti-tumor immune response were measured. The tumor was heated to a core temperature of 42 °C for 30 min. The matured synergetic DCs were intratumorally injected 24 h following mEHT was applied.

Results

mEHT induced significant apoptosis and enhanced the release of heat shock protein70 (Hsp70) in CT26 tumors. Treatment with mEHT-DCs significantly inhibited CT26 tumor growth, relative to DCs alone or mEHT alone. The secondary tumor protection effect upon rechallenging was observed in mice that were treated with mEHT-DCs. Immunohistochemical staining of CD45 and F4/80 revealed that mEHT-DC treatment increased the number of leukocytes and macrophages. Most interestingly, mEHT also induced infiltrations of eosinophil, which has recently been reported to be an orchestrator of a specific T cell response. Cytotoxic T cell assay and ELISpot assay revealed a tumor-specific T cell activity.

Conclusions

This study demonstrated that mEHT induces tumor cell apoptosis and enhances the release of Hsp70 from heated tumor cells, unlike conventional hyperthermia. mEHT can create a favorable tumor microenvironment for an immunological chain reaction that improves the success rate of intratumoral DC immunotherapy.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1690-2) contains supplementary material, which is available to authorized users.

Laparoscopic Gastric Plication - One Year of Bariatric Surgery in the Emergency County Hospital of Baia Mare

The main advantages of the laparoscopic gastric plication, in comparison to other bariatric surgery techniques, are the lowest costs and the fewest postopertive complications. This study shows our first year experience with this procedure in the Emergency County Hospital of Baia Mare.

METHODS

The first 14 laparoscopic gastric pulications performed in 2014 were studied retrospectively: there were 13 women and one man, with age ranging from 25 to 60 years old and a body mass index (BMI) from 35,7 to 59,8. Postoperative, the patients' evolution was evaluated 9 days, 1 month, 3 months, 6 months, 1 year after the surgery and before writing this paper, taking into account excess weight loss percentage and comorbidities' progress.

RESULTS

The average weight loss was 21,42 kg and the weight loss percentage was 36,52%. There were no postoperative complications in need of surgical reintervention.

CONCLUSIONS

The results were very good, the costs were low and the postoperative complications had a low rate. Therefore, there is a recommendation on performing this surgery in every hospital equipped for laparoscopic surgery.

Emergency surgery in colorectal cancer: experience of a county hospital at a 10-year interval. Comparison of immediate postoperative results

A great majority of procedures for colorectal cancer are performed as emergencies, implying a high morbidity and mortality. The aim of this study is to compare the immediate postoperative results of emergency procedures for colorectal cancer between a 10 year interval in a single centre. We performed a retrospective research of the patients files, totalizing 24 emergency operations in 2001 and 22 emergency operations in 2011. We followed demographic data, the complication which lead to emergency surgery, the time interval between the onset of the complication and the time of surgery, the type of procedure performed, postoperative morbidity and mortality. In 2001 we noticed morbidity in 66.66% of the cases (16 patients)and a mortality of 41.66% (10 patients), while in 2011 the postoperative morbidity was 54.54% (12 patients) and a mortality of 36.36% (8 patients).

CONCLUSION

although both morbidity and mortality rates decreased in a 10 year interval, they still present high values, and the difference is not statistically significant(p = 0.21 and 0.40).

Current status of oncothermia therapy for lung cancer

Lung cancer is one of the most common malignant tumors, and it has the highest death rate. Oncothermia is a feasible and successful treatment for lung cancer. Results show a remarkable survival benefit for patients, with a good quality of life. The treatment has no, or in some cases mild, side-effects and could decrease the adverse effects of the complementary treatment. Applying oncothermia together with other treatment methods could increase the effects and result in better performance. A comparison of studies demonstrates a good correspondence in the data, which strengthens the reliability of the studies, and clearly shows the feasibility of the application of oncothermia to treating all kinds of pulmonary malignancies including non-small-cell and small-cell primary tumors, and all of the metastatic diseases of the pulmonary system.

Oncothermia: a new paradigm and promising method in cancer therapies

In "hypethermia", the procedure of raising the temperature of a part, or the whole body, up to 42 degrees C to kill cancer cells for a defined period of time is applied alone or as an adjunctive with various established cancer treatment modalities such as radiotherapy and chemotherapy. However, "hyperthermia" is not generally accepted as conventional therapy due to the complications of deep heating and lack of focusing of the heat effect only for malignant tissues. The idea of oncothermia solves the selective deep action on malignant tissue on nearly cellular level. Oncothermia is highly improved, safe and effective "hyperthermia" in clinical cancer therapy supported by in vivo, in vitro, and human research as shown in this article. Advantage of oncothermia: while the classical insufficiently, focused "hyperthermia" has to heat up in case of the multiple lesions overlapping all the volume, which contains both normal tissues and malignant tissues; while oncothermia automatically focuses on the malignant tissues in its multiple places, without treating the healthy tissue in between. The modulated radiofrequency current (RF) flows through the malignancies only. The radiofrequency modulated current with 13,56 MHz (fractal modulated) between 2 electrodes automatically focuses through malignant tissues with lower impedance and will flow mainly in the extracellular electrolyte because the normal cells are electronically isolated by their membrane by more than one-million V/m electrical field strength. Oncothermia today has the ability to be a candidate to a widely accepted modality of the standard cancer treatment.

[Coumarin-induced necrosis--a rare complication of oral anticoagulant therapy]

Coumarin-induced skin necrosis represents a clinical entity that occurs very rarely, with an approximate incidence of 0.01-0.1% at patients following oral anticoagulant therapy. Most of the cases become clinical manifest between the 3rd and 6th of anticoagulant treatment (there were reports of late onset of skin necrosis after 15 years of anticoagulant therapy) and the most involved areas include breast, buttocks and thighs microcirculation-rich areas. Early symptoms include paresthesia and sensation of tension associated with an erythematous flush in the affected area. Lesions are well demarcated, painful, initially erythematous or hemorrhagic, with the onset of skin necrosis in the end stage. Early lesions can be reversible with the discontinuation of anticoagulant therapy, but skin necrosis can reoccur even without any other coumarin based treatment. We report the case of a 55-year-old female who presented with coumarin-induced skin necrosis affecting the right breast and the right deltoid area.

Oncothermia treatment of cancer: from the laboratory to clinic

Oncothermia is a long-time applied method (since 1989) in oncology. Its clinical results excellently show its advantages, however the details of its mechanism are under investigation even today. The method is based on a self-selective process of energy concentration and targets the membrane of the malignant cell, using the temperature gradient and the beta-dispersion of the membrane proteins. To prove the theory we show the experimental evidences in vitro experiments where we showed the definite difference between the conventional heating and the oncothermia at the same temperature. In the next step, we studied some xenograft nude-mice models, verifying the temperature-dependent and non temperature dependent factors. In addition, the synergic effect with some chemotherapies were studied, having more efficacy of the oncothermia with drugs than the conventional heating. These experiments show the definite advantages of the oncothermia compared to its classical counterpart, acting on the same temperature. We have also proved the beneficial effect of oncothermia treatment in the veterinary practice Oncothermia is applied in numerous clinics and hospitals, and we would like to show some characteristic case-reports and also the clinical benefit on the survival time elongation of liver-, pancreas-, brain-, and lung-tumor-lesions.

Proteomic Profiling of Breast Carcinomas Based on Claudin Expression Pattern

INTRODUCTION. With the advent of molecular techniques, the UNC workgroup (Perou 2000) has identified at least five biologically distinct subtypes (luminal A, luminal B, Her2+, triple-negative, normal-like) with genomic characterization of human breast tumors. The same lab (Herschkowitz 2007) identified a new and rare molecular subtype of human breast cancer which is now being referred to as the claudin-low subgroup. In our study, we aimed to perform a thorough analysis of the claudin, beta-catenin and E-cadherin protein expression pattern in invasive ductal (IDCs) and lobular (ILCs) breast carcinomas of different grades, their corresponding lymph node metastases (LNMs) and normal adjacent tissues NATs). METHODS. Tissue microarrays of 98 samples (59 IDCs: 20 grade 3, 26 grade 2 and 13 grade 1; 39 ILCs: 8 grade 3, 24 grade 2 and 7 grade 1), their corresponding LNMs and NATs have been analyzed immunohistochemically for beta-catenin, claudin-1, -2, -3, -4, -5, -7 and E-cadherin expression. The stained slides were digitalized with a slide scanner and the reactions were evaluated semiquantitatively according to our previous practice (Kulka 2009). RESULTS. Based on our evaluation, we were able to conclude the following significant results: 1) There is a markedly different expression of beta-catenin, claudin-1, -3, -4 and -7 in normal and neoplastic tissues. 2) Claudin-1, -2 and E-cadherin are able to differentiate ductal and lobular invasive carcinomas. 3) In E-cadherin-negative IDCs beta-catenin and claudin-7 is expressed on lower levels than in the E-cadherin-positive IDCs. In E-cadherin-positive ILCs the beta-catenin, claudin-4 and -7 is expressed at higher levels than in E-cadherin-negative ILCs. 4) Claudin-1 and -2 protein expression in the molecular subtypes can also distinguish luminal subtypes from each other and the HER2+ and triple-negative group. 5) Claudin-3 and E-cadherin or claudin-4 and -7 are both able to separate a claudin-low subtype of tumors with confidence.This later subclass also expresses beta-catenin on a lower level than the others. 6) Hierarchical clustering of primary carcinomas based on claudin expression reflects proliferation rates of the primary tumors. 7) Beta-catenin, claudin-1, -2 can differentiate primary carcinomas and lymph node metastases. 8) Histological grade correlates with claudin-1, -4 and -7 expression. CONCLUSION. According to our observations, the expression of TJ molecules, especially claudins, are different in tumors compared to normal breast tissue. Also, we could identify a claudin-low tumor subtype based on the loss of claudin-4 and -7 expression. Certain claudins are also differently expressed in the lymph node metastases as demonstrated by immunohistochemistry. Claudin profile of breast tumors correlates with histopathological variables and most likely it reflects an important mechanism of cancer differentiation and progression.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6123.

Do field-free electromagnetic potentials play a role in biology?

All bio-systems are imperfect dielectrics. Their general properties however cannot be described by conventional simple electrodynamics; the system is more complex. A central question in our present paper is centered on a controversial debate of the possible effect of the zero fields (only potentials exist). We show that the identical use of the "field-free," "curl-free," and "force-free" terminologies is incorrect, there have definitely different meanings. It is shown that the effective electro-dynamical parameters that describe and modify living systems are the potentials and not the fields. We discuss how the potentials have a role in biological processes even in field-free cases.

[Left laparoscopic lobectomy]

The authors present a case of a 61-year-old patient diagnosed with a hepatic tumor located in the second segment with expression on the anterior (diaphragmatic) side. The diagnosis and treatment applied in this case are presented. The specific feature was the surgical intervention because it was performed a left laparoscopic lobectomy using the LigaSure Atlas sealer. The short hospitalization period and quick recovery make this method an efficient one, with a wide application. Laparoscopic surgery started with a cholecystectomy which was performed by Mouret in 1987. Since then it knew a continuous development with progressive extension of this type of approach to almost all of the digestive tract organs, cavitary as well as parenchymal organs like liver or spleen. Second and third bisegmentectomy was made for the first time in 1996 by Azagra. The segments II, III, IVb, V and VI are the most frequently resected in hepatic laparoscopic surgery. Surgeons are more interested in left hepatic lobe diseases because of the anatomy which makes the approach of the biliary and blood vessels easier. Lately we assist to an increase of hepatic cancer incidence, primary or secondary; therefore we consider necessary the development of hepatic laparoscopic surgical techniques.

Strong synergy of heat and modulated electromagnetic field in tumor cell killing

BACKGROUND AND PURPOSE

Hyperthermia is an emerging complementary method in radiooncology. Despite many positive studies and comprehensive reviews, the method is not widely accepted as a combination to radiotherapy. Modulated electrohyperthermia (mEHT; capacitive, electric field modulated, 13.56 MHz) has been used in clinical practice for almost 2 decades in Germany, Austria and Hungary. This in vivo study in nude mice xenograft tumors compares mEHT with "classic" radiative hyperthermia (radHT).

MATERIAL AND METHODS

Nude mice were xenografted with HT29 human colorectal carcinoma cells. 28 mice in four groups with seven animals each and two tumors per animal (totally 56 tumors) were included in the present study: group 1 as untreated control; group 2 treated with radHT at 42 degrees C; group 3 treated with mEHT at identical 42 degrees C; group 4 treated with mEHT at 38 degrees C (by intensively cooling down the tumor). 24 h after treatment, animals were sacrificed and the tumor cross sections studied by precise morphological methods for the respective relative amount of "dead" tumor cells.

RESULTS

The effect of mEHT established a double effect as a synergy between the purely thermal (temperature-dependent) and nonthermal (not directly temperature-dependent) effects. The solely thermal enhancement ratio (TER) of cell killing was shown to be 2.9. The field enhancement ratio (FER) at a constant temperature of 42 degrees C was measured as 3.2. Their complex application significantly increased the therapeutic enhancement to 9.4.

CONCLUSION

mEHT had a remarkable cancer cell-killing effect in a nude mice xenograft model.

[Diagnosis, therapeutic attitude and prognostic factors of the tumors of body and tail of the pancreas--a case presentation and a review of the literature]

Neoplasms of the body and tail of the pancreas are rarer in comparison to those occurring in the head of the pancreas, representing only 10% of the total number of pancreatic malignancies. They poses even in present one of the greatest therapeutic challenge for the surgeon as their diagnosis and treatment are difficult to be done mainly due to specific anatomic position of the pancreas as well as due to the absence of any specific symptomatology belonging to the tumors of the body and tail of the pancreas having smaller dimensions. Here we are presenting two cases of neoplasms of the body and tail of the pancreas from the archives of 3rd Surgical Clinic, Cluj Napoca, hereby illustrating the experience of this clinic in the domain of high class pancreatic surgery. The two patients, having 55 and 43 years of age respectively, were diagnosed with neoplasm of the body and tail of the pancreas for which they had undergone the procedure of distal pancreatectomy along with the resection of the spleen. Out of those two cases, the first case had an invasive process of the tumor in the region of the superior mesenteric vein for what it was performed a segmental resection of the superior mesenteric vein with a termino-terminal anastomosis of the remaining two proximal and distal ends, while the second case inspite of its large dimension of the tumor (approximately 10 c.m in diameter) did not have any loco-regional invasion or any kind of distal metastasis which rendered it possible for a radical intervention. The aim of this case presentation as well as the reviews of the literatures belonging to this specialised domain is to sustain the idea that pancreatic surgery should be performed in those specialised surgical centres having profound knowledge as well as all the existing information about the diagnostic procedures, therapeutic attitude and prognostic factors of this specific pathology.

[Duodenal adenoma--a rare cause of upper gastrointestinal hemorrhage]

The tumors of the small bowel are rare entities, whose incidence comprises ca. 1-5% of the total amount of tumors in the digestive tract. Most of the cases involve the ileum and duodenum is least involved. The most frequently encountered duodenal tumors are the Brunner's Gland Adenomas. We can encounter unique or multiple lesions, sessile or pedunculated which develop proximal to duodenal papilla and are usually less than 1 cm in diameter although 12 cm lesions have been reported. In most of the cases they remain asymptomatic and constitute incidental discoveries. Sometimes they can present complications such as obstruction, hemorrhage and malignant transformation. Diagnosis is difficult due to the lack of symptoms and is delayed by an average of 6 months from symptoms onset. Barium contrast studies and superior digestive endoscopy is performed in most of the cases to reveal the diagnosis, but other methods, such as CT or ultrasound can be useful. A case of duodenal adenoma is described; the patient was admitted suffering digestive hemorrhage, which resulted in melena, secondary anemia, and ulcerous dyspeptic syndrome.

Hyperthermia today: electric energy, a new opportunity in cancer treatment

Hyperthermia is an ancient, but nowadays rapidly developing treatment method in tumor-therapy. Its new paradigm applied in the electro-hyperthermia (oncothermia), which provides energy by means of electric-field and produces non-equilibrium thermal situation in the tissue. The temperature gradients formed in stationary conditions, destroy the membrane of the malignant cells and selectively eliminate the cancer tissue. The characteristic control parameter is the absorbed energy-dose, which is partly used to make the distortions, partly to increase the temperature of the target. This type of technique could be applied for some tumor sites, including brain, soft tissues, liver and abdominal masses, pancreatic cancer, head and neck tumors as well.

[Gastrojejunocolic fistula--a rare complication of stomach surgery]

The gastrojejunocolic fistula represents a clinical entity that occurs very rarely following gastro-jejunal anastomoses and manifests itself clinically and paraclinically by a severe malabsorption syndrome. The results of the physiopathological approach may be summed up as follows: reduced level of seric proteins, fluid and electrolytic depletion, deficiencies in the absorption of the vitamins soluble in fats and water, which may all vary from mildness to severeness, depending on the flow rate of the fistula. Most often, the diagnosis is set by performing barium enema, which is positive for all cases, whereas the barium passage is less efficient, enabling diagnosis in only 33% of the cases. The radiological image may be reduced on principle to one single sign: the abnormal fistulous trajectory (barium passes from the stomach directly into the colon or the enema fills the gastric lumen). It is recommended that surgical treatment be performed in a single stage, by resecting the entire fistula and re-establishing the gastro-jejunal and colic continuity. We report a case of gastrojejunocolic fistula in a patient that underwent 2/3 gastric resection for gastric ulcer 9 years ago.

Axial-vector interaction with bio-systems

One remarkable part of the biological process is that it is self-similar stochastic, originating from a system of a large number of interacting parts. Our objective is to study the thermodynamics and the pink-noise behavior of these systems. Our model is based on the Langevin equation, describing the transport properties of biological systems. Using Onsager's formulation of the microscopic reversibility, we study the effects of the interactions characterized by axial-vectors (angular-velocity-vector, vector-potential) on self-similar processes and interactions. In the presence of any axial-vector interaction, Casimir anti-symmetry relations determine the processes, changing the coupling of the transport properties. This modifies the noise-spectrum of the system as well. Moreover, the modified system loses its equivalent entropy in all time-scales (also characteristic of the Gaussian pink-noise), so this unique dynamic state of the biological systems disappears by interaction with an axial-vector field. This could modify the usual magnetic explanations of the migration orientation of animals.

On the thermal noise limit of cellular membranes

Comparison of thermal noise limits and the effects of low frequency electromagnetic fields (LFEMF) on the cellular membrane have important implications for the study of bioelectro-magnetism in this regime. Over a decade ago, Weaver and Astumian developed a model to show that thermal noise can limit the efficacy of LFEMF. A recent report by Kaune [Kaune (2002) Bioelectromagnetics 23:622-628], however, contradicted their findings. Kaune assumes that the conductance noise current of cell membrane can be decomposed into two components, where one of them is identical regarding all segments (coherent), while the other is different (incoherent). Besides, this decomposition is not unequivocal and contradicts to the statistical independence of the segment noise currents, and therefore to the second law of thermodynamics as well. We suggest the procedure based on the method of symmetrical components, by the means of which we can re-interpret the result of Kaune in a correct way.

Pink-noise behaviour of biosystems

Pink (1/f) noise is one of the most common behaviours of biosystems. Our present paper is devoted to clarify the origin of this interesting phenomenon. It is shown that the stationary random stochastic processes under self-similar conditions (as we have in living objects) generate pink noise independently of the kind and number of variables.

Neurohypophysial hormone secretion in hyperprolactinaemic women

Prolactin (PRL) has been reported to promote antidiuresis and increase intestinal water-electrolyte absorption, whereas osmolar changes have been shown to influence PRL secretion. However, the mechanisms of action of PRL on the salt-water balance remain unclarified. The present clinical study targeted the effects of hyperprolactinaemia on the secretion of arginine-8-vasopressin (AVP), oxytocin (OXT) and cortisol. Plasma AVP and OXT were measured by radioimmunoassay, and cortisol by fluorimetry. In healthy women (21-39 y, n=6), an oral water load (OWL, 20 ml/bw) significantly suppressed the plasma levels of AVP, OXT and cortisol, and the PRL level too tended to decrease. In hyperprolactinaemic females (22-41 y, n=6, three with pituitary adenomas), water retention was registered following an OWL, together with paradoxical AVP and OXT level increases, whereas the cortisol response remained normal, and the PRL level did not change at all. Histamine (0.5 mg sc) stimulated the release of AVP, OXT and cortisol in the control and hyperprolactinaemic groups alike. These data suggest that alterations in AVP and OXT hypersecretion may contribute to the water retention in hyperprolactinaemia.