The use of information process indices for the prediction of sympathectomy efficiency in complex regional pain syndrome

The key role of information processes for ensuring the optimal sanogenesis in humans was shown by the wavelet-analysis of skin microvascular blood flow oscillations in 64 patients with complex regional pain syndrome after sympathectomy. The early reorganization of information in the trophotropic direction at the level of microvascular tissue systems, and its predominance and preservation along the microvascular networks facilitate optimal adaptive reactions and, as a result, are conducive to maximum treatment efficiency. In these cases, the complete elimination of disease and the achievement of excellent treatment results are possible. The maximum treatment efficiency could not be reached without the above-mentioned informational changes. On the contrary, the predominance and preservation of ergotropic information in the early periods after surgery were unfavorable for the prediction of the clinical outcome of sympathectomy. Tissue sympathectomy is not required for the formation of the trophotropic type of information exchange in microvascular networks; it is enough to achieve a certain threshold of a sympathetic activity decrease. The results obtained may be useful for investigating the physiological mechanisms of informational treatment technologies (homeopathy etc.).     

Oscillatory structures of blood flow reflect the dynamics of information processes in microcirculatory networks

Laser Doppler flowmetry with wavelet analysis of oscillations of the blood flow in the glabrous skin of the second and fifth fingertips of 30 healthy individuals and 57 patients before and after median and ulnar nerve sutures (n = 29) and after hand sympathectomy (n = 28). Information processes in microvascular networks include both the stationary and oscillatory components. This study is the first to apply wavelet analysis of the blood flow oscillatory organization to studying the dynamics of information processes in microcirculatory networks. A methodological approach was proposed to estimate the total quantity of information, the value and semantic features of different information channels and the information regime (multichannel or resonance) in microcirculatory networks. The deficit of both general information and its content (particularly, of external information), a decrease in the accessibility to the information and the system of self-organization were typical during the denervation syndrome. The semantic information signs changes mainly after sympathectomy. The dynamics of the information process reflects the functional significance of microcirculation in the course of nerve regeneration and skin reinnervation. The increment in information quantity with trophic content occurred at the preimpulse stage of nerve regeneration; it corresponds to the quantitative development of skin microvascular networks for trophic support of reinnervation. The semantic information content was predominantly modulated at the impulse stage due to the increase in homeostatic control intensity. Information peculiarities in the transitional period (from the preimpulse to impulse stage) included a decrease in sporadic processes, an increase in determinism in the system control, the predomination of the trophic content assimilation with the increment in the myogenic activity proper, and the possibility of both multichannel and resonance regimes. The general biological law of the antientropic importance of information for decreasing stochastic processes and the system control support has been confirmed.     

Salvage of ischemic digits using a lateral arm fascial flap

Four patients underwent microvascular transfer of a lateral arm fascial flap to salvage severely ischemic digits by means of induction of neovascularization. The cause of the digital ischemia was direct trauma (crush injury) in one patient and chronic embolic phenomena (proximal arterial occlusion) in three patients. None of the patients had responded to traditional therapy, including treatment with one or more of the following: anticoagulation, lytic therapy, oral vasodilators, digital sympathectomy, and vein bypass grafting. Each patient underwent noninvasive (Doppler ultrasound, digital pressures, digital temperatures, vascular refill) and invasive (angiogram) vascular assessment preoperatively. After microvascular transfer of the lateral arm fascial flap, all patients reported symptomatic relief, and objective improvements were documented by both noninvasive and invasive assessment criteria. One patient developed a seroma at the donor site; another experienced a late complication of thrombosis of the flap after his wound dehisced. A 6-month follow-up evaluation demonstrated neovascular collateralization and stable improvement without regression in the remaining patients. The authors present their clinical experience and propose a treatment algorithm for patients with chronic digital ischemia.     

The Ergotropic Activity Index as an Integral Indicator of the Suprasegmental Autonomic Activity

Thirty healthy males between 19 and 25 years of age were examined to develop a method for estimating the suprasegmental autonomic activity. Analysis of the data obtained revealed the most informative indices along with a factor that had positive correlations with the ergotropic autonomic activity indices and negative correlations with the trophotropic autonomic activity indices. This factor was termed the ergotropic activity index. The information content of this factor was analyzed in a thermal environment and clinically in 40 patients with autonomic crises. The effectiveness of this method was tested, and the method was judged to be sufficiently adequate for clinical practice. The procedure developed for estimating the suprasegmental autonomic activity was demonstrated to be a highly informative method for revealing the predominance of either ergotropic or trophotropic activity in healthy subjects and patients with autonomic dystonia and for forecasting heat tolerance in humans. This method can be used during physiological and neurophysiological observations and in clinical practice     

Multiple-year optimization of conservation effort and monitoring effort for a fluctuating population

We consider optimal conservation strategies for an endangered population. We assume that juvenile survival is affected by unpredictable environmental fluctuation and can be improved by costly conservation effort. The initial population size is not accurately known at the time that the conservation effort level is chosen, but the uncertainty of its estimate can be reduced by a costly monitoring effort. In a previous paper, we analysed the optimal management strategy that minimizes a weighted sum of extinction probability and economic costs when only a single year is considered. Here we examine the case in which the conservation period lasts for several years by dynamic programming with incompletely observed process states. We study the optimal levels of the conservation and the monitoring efforts, and their dependence on the length of the conservation period and other parameters. The main conclusions are: (1) The optimal conservation effort in the first year depends on the accuracy of the information on the population size in the first year, but is almost independent of the accuracy of the information in later years. (2) When the risk of population extinction is small, the optimal conservation effort increases with the uncertainty of the population size. In contrast when the population is endangered, the optimal conservation effort decreases with the uncertainty of the population size. (3) The optimal conservation and monitoring efforts both increase with the length of the conservation period, provided that the population is relatively safe. However, if the population is endangered, both types of effort become smaller when the conservation period increases.     

Cardiovascular, metabolic and endocrine effects of chemical sympathectomy and of adrenal demedullation in fetal sheep

A procedure in fetal sheep for causing peripheral sympathectomy by regular intravascular guanethidine sulphate administration and for causing adrenal demedullation by intragland injection of acid formalin is reported. Demedullation substantially removed adrenaline from the fetal circulation, but has a small effect only on noradrenaline. Plasma noradrenaline levels were depressed by 50% when demedullated fetuses were also subject to peripheral sympathectomy by guanethidine sulphate treatment. This provides some evidence that the paraganglia in the sheep fetus contributes to resting plasma catecholamines. Furthermore the ability of adrenal demedullation to increase markedly this pool of extra-adrenal chromaffin tissue indicates that in the fetus adrenal activity regulates the growth of these para-aortic bodies. In response to sympathectomy plasma vasopressin concentrations rose substantially, whilst adrenal demedullation caused a small rise. Demedullation and sympathectomy depressed fetal plasma glucose and elevated plasma cortisol. In both sympathectomised and adrenal demedullated fetuses resting heart rate and blood pressure was not depressed. However in those with a depleted peripheral nervous system periods of cardiovascular instability were apparent after 2-3 days of treatment with guanethidine sulphate. Hence there were regular episodes where fetal blood pressure and heart rate fell sharply followed 60-90s later by very large increases in blood pressure sustained for up to 10 min and associated with substantial production of plasma vasopressin and catecholamines. These results show that fine cardiovascular control in the fetus requires an intact sympathetic system as the endocrine system is too slow responding to effectively maintain reflex vascular control.     

Comparison of effects of surgical and chemical sympathectomy on beta adrenergic and muscarinic receptors of parotid gland of young and adult rats

Surgical (removal of a superior cervical ganglion) or chemical [(administration of a single dose of 6 hydroxydopamine (6 OHDA) (50 mg/kg dose body wt)] sympathectomy of rats at 2 or 8 days of age resulted in an increase in [3H]DHA binding of membranes of parotid gland of young rats (age range 21 days to 48 days). The increase progressed with postnatal age; at 21 days of age (surgical sympathectomy), it was 13%; at 32 days of age with 6 OHDA, it was as much as 34%, but only 26% at 42 days of age with surgical sympathectomy. No change in [3H]QNB binding was observed at any postnatal ages following neonatal sympathectomy. Conversely, surgical sympathectomy of the parotid of adult rat resulted in little or no change in [3H]DHA binding at 1, 2, 3, or 4 weeks postdenervation, but [3H]QNB binding was reduced at all periods, with the reduction from control values at 2 weeks being 34%, and at the subsequent intervals, 24-26%. The increase in number of beta adrenoceptors of the parotid gland was not related to the kind of sympathectomy (chemical or surgical) or neonatal age at which it was done; however, duration of the denervation for 2-3 weeks was necessary for the receptor increase to occur. In the adult, however, the duration of the denervation was of no importance since change in number of beta adrenoceptors did not occur at 1, 2, 3, or 4 weeks after surgical denervation but did occur after only 1 week after of reserpine-induced denervation. QNB binding was decreased with surgical sympathectomy as well as reserpine-induced sympathectomy of adult parotid gland; norepinephrine concentration was decreased to levels of a few percent of innervated glands. The relation between development of glandular supersensitivity and increase in beta adrenoceptors is discussed.     

Plasticity in developing rat uterine sensory nerves: the role of NGF and TrkA

In the present study we investigated the effects of infantile/prepubertal chronic oestrogen treatment, chemical sympathectomy with guanethidine and combined sympathectomy and chronic oestrogen treatment on developing sensory nerves of the rat uterus. Changes in sensory innervation were assessed quantitatively on uterine cryostat tissue sections stained for calcitonin gene-related peptide (CGRP). Uterine levels of NGF protein, using immunohistochemistry and ELISA, and mRNA, using Northern blots and in situ hybridization, were also measured. Finally, levels of TrkA NGF receptor in sensory neurons of T13 and L1 dorsal root ganglia (DRG), which supply the uterus, were assessed using densitometric immunohistochemistry. These studies showed that: (1) chronic oestrogen treatment led to an 83% reduction in the intercept density of CGRP-immunoreactive nerves; (2) sympathectomy had no effect on the density of uterine sensory nerves or on the pattern of oestrogen-induced changes; (3) NGF mRNA and protein increased following sympathectomy or chronic oestrogen treatment; and (4) oestrogen produced increased intensity of labelling (28%) for TrkA receptors in small-diameter sensory neurons, but decreased labelling (13%) in medium-sized neurons, which represent the large majority of the DRG neurons supplying the upper part of the uterine horn. Contrary to expectations, increased levels of NGF after sympathectomy and oestrogen treatment did not lead to increased sensory innervation of the uterus. The possibility that alterations in neuronal levels of TrkA contribute to the lack of response of uterine sensory nerves to the oestrogen-induced increase in NGF levels is discussed.This work was supported by The Wellcome Trust, UK (CRIG Grant 058122/Z/99/Z/JC/KO), and PEDECIBA, Universidad de la República, Montevideo, Uruguay     

NEWER METHODS FOR SELECTION OF PATIENTS FOR LUMBAR SYMPATHECTOMY

The degree of vasodilatation achieved by various diagnostic methods (arterial occlusion, ganglionic block established by certain agents, lumbar sympathetic block, spinal anesthesia, and indirect heating) was studied by means of the pneumo-plethysmogram as well as through readings of skin temperature and skin resistance. The data obtained were interpreted as to their value in determining the type of patient with vascular disease for whom lumbar sympathectomy would be of noticeable benefit. Arterial occlusion proved itself a rapid and simple method which in most patients produced satisfactory results. As a rule, lumbar sympathectomy was effective in patients who preoperatively had shown a positive response upon release of arterial occlusion. A negative response, that is, absence of significant increase in blood flow, does not necessarily indicate organic disease, and cannot be taken to mean that lumbar sympathectomy would always be ineffective. Ganglionic block, using 2.6 dimethyl piperidinium bromide or tetraethylammonium ion, was generally less reliable in indicating the probable results of sympathectomy than lumbar sympathetic block or indirect heating. Lumbar sympathetic block with procaine was followed by a greater increase in skin temperature and blood flow than spinal anesthesia, and permitted far more accurate conclusions as to the probable outcome of sympathectomy. Subsequent to indirect heating the plethysmogram showed characteristic differences depending on the degree of vascular disease present. From the effect of this simple, safe and painless method upon the relative blood flow to the toe it becomes possible to arrive at a comparatively accurate estimate of the clinical benefit to be expected from lumbar sympathectomy.     

Respiration in awake cats: sympathectomy and deafferentation of carotid bifurcations

Respiratory effects of sympathectomy of the carotid bifurcations and, in a subsequent experiment, bilateral carotid sinus nerve section were examined in six awake resting cats. In each intact and denervated state, sequential breaths were analyzed at 10-min intervals up to 80 min. Individual breath frequency (f), tidal volume (VT), and ventilation (V = f X VT) were determined. In individual cats, sympathectomy or deafferentation could cause significant increases or decreases in ventilation or no change. Thus the range of spontaneous variability in breath V as well as minute ventilation (VE), averaged for the group, were not consistently altered in the same direction by either sympathectomy or deafferentation of the carotid bifurcations. Interestingly, in most cats after both sympathectomy (5 of 6) and deafferentation (4 of 6), VT increased and f decreased relative to V. Despite this, after sinus nerve section in two cats arterial PO2 decreased and arterial PCO2 tended to increase relative to VE, suggesting possible effects of deafferentation on ventilation-perfusion balance. Sympathectomy also affected timing such that inspiratory time began to exceed 0.5 of the breath duration at a lower breath f; this effect of sympathectomy was reversed to intact values by subsequent sinus deafferentation. Thus, in eupneic awake cats, sympathetics normally suppress reflex modulation of central timing from carotid chemoreceptors and/or baroreceptors.     

Microvascular transplantation of the rat submandibular gland

Xerostomia results from salivary gland irradiation during treatment of head and neck malignancies. In addition to having difficulty with speech and swallowing, these patients experience loss of taste, dental caries, and chronic fungal infections. The paired submandibular glands provide 70 percent of the normal salivary flow and are difficult to shield during radiation therapy. Another sicca condition, xerophthalmia, may result from facial nerve injury or other medical disorders and results in pain, corneal ulceration, and possible vision loss. Treatment options for xerostomia are limited, and management of xerophthalmia usually focuses on the eyelids, rather than the fundamental problem of inadequate secretory protection. In this study, a rat model for submandibular gland microvascular transplantation was developed to assess the feasibility of salivary tissue transfer. Sixteen rats underwent submandibular gland transplantation from the neck to the groin. Fourteen of these rats underwent microvascular anastomosis of the vascular pedicle. Ten glands were assessed for viability at 4 days after transplantation, and four glands were examined after 7, 10, 14, or 21 days. By gross and histologic examination, 93 percent of transplanted glands showed expected long-term viability after at least 4 postoperative days. Microvascular techniques were shown to be applicable to the transplantation of submandibular gland salivary tissue. This has not previously been shown in a rat model. It is possible that submandibular glands could be transplanted to the eye for treatment of xerophthalmia and out of the neck during irradiation of the head and neck, with subsequent replantation after treatment as a means of preventing permanent xerostomia.     

Effect of interleukin 1beta on rat thymus microenvironment

The effect of interleukin 1beta on the thymus of control and chemically sympathectomized adult and aged rats was studied with the aim of assessing the importance of adrenergic nerve fibres (ANF) in the regulation of some immunological functions.The whole thymus was removed from normal, sympathectomized (with the neurotoxin 6-OH-dopamine) and treated (interleukin 1beta) rats. Thymic slices were stained with eosin orange (for the recognition of microanatomical details of the thymic microenvironment) and with Bodian's method for staining of nerve fibres. Histofluorescence microscopy was employed for staining ANF and immunofluorescence was used for detecting NPY-like immunoreactivity. All images were submitted to quantitative morphometrical analysis and statistical analysis of data. Moreover, the amount of proteins and noradrenaline was measured on thymic homogenates. The results indicate that in normal conditions the formation of the thymic nerve plexi in the rat is complex: the majority of ANF are destroyed after chemical sympathectomy with 6-OH-dopamine and do not change after treatment with interleukin 1beta; on the contrary, treatment with interleukin 1beta induces substantial changes in the fresh weight of the thymus, the thymic microenvironment, thymic nerve fibers, ANF, NPY-like positive nerve fibres, and on the total amount of proteins and noradrenaline in rat thymic tissue homogenates.Immunostimulation with interleukin 1beta induces substantial changes in the whole thymus, in its microenvironment and in ANF and NPY-like nerve fibres. After chemical sympathectomy, no significant immune response was evoked by interleukin 1beta, since the majority of ANF was destroyed by chemical sympathectomy.     

Effects of short-term treatment with vitamin E in systemic sclerosis: a double blind, randomized, controlled clinical trial of efficacy based on urinary isoprostane measurement

This double blind randomized controlled trial was designed to investigate whether short-term vitamin E treatment at doses of 500 and 1000 mg/day, compared to placebo, decreased urinary F(2)-isoprostanes and improved the microvascular perfusion after cold exposure in patients suffering from SSc. Thirty-three eligible patients were randomly assigned in a 1.3:1:1 ratio to receive placebo, vitamin E 500 mg, or vitamin E 1000 mg daily for 3 weeks. Clinical examination, analysis of plasma vitamin E, urinary F(2)-isoprostane levels and a whole body cooling test were performed at baseline and after a 3-week period of treatment. Urinary 15-F(2t)-IsoP levels and cutaneous blood flow variation in response to cold did not significantly differ before versus after treatment in any group. Furthermore, no difference was found between groups after 3 weeks of treatment. We show that 3-week vitamin E treatment at doses of 500 or 1000 mg/day neither decreases the basal rate of lipid peroxidation nor improves microvascular perfusion after cold exposure. These data does not support the need for phase III clinical trials to test efficacy of vitamin E in SSc.     

Inhibition of vascular endothelial growth factor/vascular permeability factor action blocks estrogen-induced uterine edema and implantation in rodents

Estrogen induces a rapid increase in microvascular permeability in the rodent uterus, leading to stromal edema and a marked increase in uterine wet weight. This edema is believed to create an environment optimal for the growth and remodeling of the endometrium in preparation for implantation and pregnancy. Increased endometrial microvascular permeability also occurs in conjunction with implantation. Estrogen-induced uterine edema is immediately preceded by an increase in the expression of vascular endothelial growth factor (VEGF), a potent stimulator of microvascular permeability. The objective of this study was to determine to what degree immunoneutralization of VEGF would interfere with a) estradiol-induced uterine edema and b) pregnancy. In the first set of experiments, immature female rats were injected with either VEGF antiserum or normal rabbit serum (NRS) prior to 17beta-estradiol treatment. Rats treated with estradiol alone showed a 57% increase in uterine wet weight at 6 h compared with controls. Injection of 200 or 300 micro l of VEGF antiserum reduced the response to only 20% and 10% above controls, respectively. In the second set of experiments, young adult female mice were treated with 100 micro l of either VEGF antiserum or NRS at 1200 h on the fourth day after mating. NRS-treated mice had normal pregnancies. VEGF antiserum, however, completely blocked pregnancy. When VEGF antiserum-treated females were examined on Day 5 for the presence of implantation sites, none were found. These results show that a) VEGF is the major mediator of estrogen-induced increase in uterine vascular permeability and b) VEGF-induced edema is absolutely essential for implantation to take place.     

Conservation effort and assessment of population size in fluctuating environments

We consider optimal conservation strategies for endangered populations. We assume that the survival of the population is affected by unpredictable environmental fluctuation and can be improved by conservation effort. Furthermore, the exact value of the initial population size is assumed to be unknown. The conservation strategy involves two aspects: investment of assessment effort, to improve the estimate of the initial population size and investment of conservation effort. Both types of effort imply economic costs. The optimal management strategy is assumed to minimize the weighted sum of extinction probability and the economic cost of the conservation and the assessment effort. (1) We first analyse the optimal conservation effort when the current population size is known accurately. (2) Next, we consider the situation in which there is limited information (i.e. a cue) on population size. (3) We subsequently discuss the cases where the cue accuracy can be improved by assessment of the population. We study the optimal level of the assessment effort and discuss its dependence on various parameters.     

微血管自律运动在高血压发生发展中的变化和意义

微循环的异常,包括微血管的稀疏和（或）微血管结构的改变,可能参与了高血压的发生发展,是造成终末器官缺血和功能障碍直至衰竭的主要原因之一。根据文献报道,微血管自律运动调控血流动力学的同时还参与信息传递并适时作出反应,改善组织灌注不足、缺血、缺氧,缓解外周压力。已有研究发现,高血压发生发展过程中,微血管自律运动频率和振幅呈现复杂的变化,可能与内皮细胞功能不足、细胞间缝隙连接减少、平滑肌细胞钙离子内流增多及钙池功能异常引起膜电位改变等有关,本文将从微循环的角度阐述高血压状态下微血管自律运动的变化并对其机制做一简要概述。     

Understanding investment in biodiversity conservation in Mexico

Documenting financial resources in biodiversity conservation is a key aspect worldwide in order to set priorities and use effectively the limited resources available. In Mexico, a megadiverse country, studies on financial resources invested in biodiversity conservation are scarce and do not address funding for conservation comprehensively. Using recent data from several sources and applying criteria based on the national priorities for conservation, we compiled, systematized and analyzed data at a national scale on financing sources, financial resources and conservation organizations and their projects. The information obtained is presented in various ways and part of it (case study) is already an information system that can be continuously up-dated. Some of the results show the following: a steady diversification of mechanisms and methods for raising funds for conservation; an increase in governmental budgets; the acknowledgment by the private sector of the importance of biodiversity conservation; a greater technical capacity in people and organizations working in conservation; a greater accessibility of financial resources to support and maintain conservation projects; yet a short term vision in conservation projects; among other. Although the results obtained through this study are a first approach, they can now be used as a baseline to continue gathering and analyzing information on conservation financing in Mexico.     

Adrenal lipid profiles of chemically sympathectomized normoxic and hypoxic neonatal rats.

Neonatal hypoxia is a common condition that elicits a coordinated endocrine response. In the neonatal rat, hypoxia induces an ACTH-independent increase in corticosterone which can be partially blocked by chemical sympathectomy. The present study sought to characterize the effects of sympathectomy on the adrenal lipid profile, since previous work suggested that augmented plasma corticosterone during hypoxia may be due to changes in adrenal lipid metabolism. Newborn rats were exposed to normoxia or hypoxia from birth to seven days of age, and guanethidine was used to produce the sympathectomy. Plasma epinephrine and norepinephrine were not significantly affected by hypoxia, while guanethidine decreased plasma norepinephrine in normoxic and hypoxic pups. Hypoxia alone increased the concentration of cholesterol esters in the adrenal gland; this increase was due to increases in cholesterol ester-associated oleic (18:1n9), docosahexaenoic (22:6n3), arachidonic (20:4n6), and adrenic (22:4n6) acids. Hypoxia also increased diglyceride-associated adrenic acid. Guanethidine treatment attenuated the hypoxia-induced increase in cholesterol ester-bound arachidonic and adrenic acids. Guanethidine also decreased saturated fatty acid concentrations and increased n3 fatty acid-enriched triglycerides. The results support the idea that the ACTH-independent corticosterone response to hypoxia in the neonatal rat is mediated by specific, sympathetically driven alterations in the adrenal lipid profile.     

Assessment of organ culture for the conservation of human skin allografts

Objective Human skin allografts are used in the treatment of severe burns and their preservation is therefore critical for optimal clinical benefit. Current preservation methods, such as 4°C storage or cryopreservation, cannot prevent the decrease of tissue viability. The aim of this study was to assess viability and function of skin allografts in a new skin organ culture model, allowing conservation parameters as close as possible to physiological conditions: 32°C, air–liquid interface and physiological skin tension. Design Twelve skin samples, harvested from 6 living surgical donors, were conserved 35 days in two conditions: conservation at 4°C and organ culture. Viability and function of skin samples were investigated at Day 0, 7, 14, 21, 28 and 35 using cell culture methods (trypan blue exclusion, Colony Forming Efficiency and Growth Rate), histopathological and histoenzymological studies (Ki67 immunostaining). Results In the two conditions, fibroblast and keratinocyte viability was progressively affected by storage, with a significant decrease observed after 35 days. No statistical difference could be observed between the two conditions. The two methods were also comparable regarding alterations of fibroblast and keratinocyte culture parameters, which were respectively significantly reduced at Day 7 and 21, compared to fresh skin. By contrast, histopathological and histoenzymological studies revealed a better preservation of skin architecture and proliferative potential at 4°C, as compared to organ culture. Conclusion These results indicate that skin organ culture does not provide significant advantages for skin allograft preservation. However, its potential use as an experimental model to study skin physiology and wound healing should be further evaluated.