Abstract:
A method and system for creating shear stress and endothelial mechanotransduction through neuromuscular stimulation of the muscle pump. Chronic application a minimum of 30 days triggers the autocrine and paracrine processes which elevates production of vasoactive substances including nitric oxide, prostacyclin, superoxide dismutase, thrombomodulin, glutathion, Krupple-like factor 2 and many others. Chronic application also promotes angiogenesis and development of collateral circulation. This is a cost-effective, non-invasive, drug-free therapy to treat vascular dysfunction and ameliorate or reverse its effects on cardiovascular health.

Description:
BACKGROUND 
     1. Field of the Invention 
     The present application relates to a method of medical treatment, and more particularly to a method for treating people with vascular health problems by the application of neuromuscular stimulation leading to the generation of endothelial mechanotransduction, which boosts endocrine, autocrine and paracrine activity resulting in an increase in vasoactive substances. 
     2. Description of Related Art 
     Blood vessels traverse all throughout our bodies. The endothelium is the inner lining of all blood vessels. It is the largest organ in the body. If flattened and spread out, it is equivalent in size to approximately six tennis courts. Once thought to be inert and unimportant, research has shown it to be an extremely important organ that exerts control over an array of mechanisms which serve to maintain vascular tone and blood fluidity by:
         Maintaining vascular smooth muscle tone   Regulating angiogenesis and cell proliferation   Mediating inflammatory and immune responses   Regulating vascular permeability   Regulating thrombolysis   Regulating leukocyte adhesion   Regulating platelet adhesion and aggregation   Regulating lipid oxidation       

     The endothelium exerts this control through endocrine, paracrine and autocrine processes wherein the endothelial cells secrete vasoactive substances such as hormones, genes, proteins, transcription factors and others, resulting in the regulatory actions listed above. This group of events is generally known as, “endothelial mechanotransduction.” Mechanotransduction refers to the processes through which cells sense and respond to mechanical stimuli by converting them to biochemical signals that elicit specific cellular responses. While shear stress and mechanotransduction are well documented in the literature, no one has proposed the use of endothelial mechanotransduction as a therapy. 
     Endothelial mechanotransduction happens in response to blood flow and laminar shear stress, induced from the mechanical forces caused by the rubbing of blood cells on the endothelium (the lining of blood vessels). When people are young, the normal physiologic levels of blood flow and shear stress keep blood vessels (and the whole cardiovascular system) healthy. Later in life, people make diet and lifestyle choices that can lower blood flow, clog the blood vessels with fatty deposits and impair the regulatory processes necessary for vascular health. The endothelium can then become dysfunctional contributing to atherosclerosis (hardening of the arteries), diabetes, hypertension (high blood pressure), delayed wound healing, vasculitis, congestive heart failure, critical limb ischemia, neuropathy and more. 
     Endothelial dysfunction is a major health problem in the U.S. with more than 65,000 peer-reviewed articles on this topic. Various different methods have been used, experimentally, to treat endothelia dysfunction. Methods involve the use of drugs, or external compression devices. 
     There are drugs labeled “NO donors” which cause the body to generate NO and several are in current tests to determine their efficacy and safety. Aside from nitroglycerin, few have made it into the marketplace and the only one in widespread use is for erectile dysfunction. Erectile dysfunction, like endothelial dysfunction, is caused by a lack of NO. These drugs can have many disadvantages and undesirable side effects when used. 
     Although electrical stimulation for medical purposes has been in use for more than a hundred years, its use has largely been defined by the effects of various types of current (i.e., galvanic, interferential, “Russian”, faradic, high voltage pulsed current, micro-current, etc.). In current practice, electrical stimulation is primarily used by physicians, physical therapists, chiropractors, athletic trainers and rehabilitation facilities for the following purposes: sore and torn muscles and tendons, bone fractures, healing of decubitus and diabetic ulcers, pain alleviation, relief from muscle spasms and treatment for disuse atrophy. The localized, minor movement of blood is often mentioned as part of the treatment. Functional electrical stimulation (FES) is primarily used to retrain muscles in patients with spinal cord or neuronal injury. 
     There are also electrical stimulators in use for narrowly defined special uses, including: implanted spinal stimulation for pain alleviation, implanted stimulation of the vagus nerve for epilepsy, U.S. Pat. No. 5,928,272, Adkins, et al (1999) and FES units for pharyngeal muscle re-education for the act of swallowing, U.S. Pat. No. 6,104,958, Freed et al (2000). 
     Several devices on the market produce electrical stimulation waveforms adequate to contract skeletal muscle (i.e. Rich-Mar Corp&#39;s Theratouch 4.7, Pro-Med&#39;s model 7560, Microvas Technologies&#39; models I and II, NeuroCare&#39;s NC1000), all of these devices, however, apply stimulation to several treatment locations simultaneously, which can create back pressure thus reducing the pumping action of the one-way valves in the venous system. Furthermore, all of these devices have an inadequate number of leads to treat the large areas or to generate the volume and velocity needed to reach therapeutic levels of mechanotransduction. 
     Several devices have attempted to achieve upregulated blood flow through means of externally applied hydraulic pressure as shown in U.S. Pat. No. 6,863,670 to Zheng (2005), or pneumatic pressure as in U.S. Pat. No. 6,358,219 to Arkans (2002). In these applications, the invention squeezes the leg by way of inflatable cuffs around the leg. The veins, in the muscles, are also squeezed, although much of the pressure is absorbed by the relaxed muscle mass which acts as a cushion to dissipate the pressure. A problem common to external compression is chaffing and bruising from the extreme pressures and repetitive squeezing of the cuffs. 
     While these inventions do manage to accomplish some movement of blood, their method is limited in effectiveness because they are squeezing through thick layers of relaxed muscles, forming a cushion and the squeezing forces are therein blunted. It is desired that pressure be applied directly to the veins in a manner similar to that seen with typical body movements. 
     One novel form of stimulation for blood flow is U.S. Pat. No. 5,195,518 to Mannion, et al (1993) which involves the surgical attachment of skeletal muscles to the heart, then applying stimulation to the attached muscle in an attempt to drive blood to an ischemic heart. The extreme costs and invasive nature of this invention would tend to limit its application. 
     Although some small strides have been made to treat endothelial dysfunction, considerable shortcomings remain. A therapy for the creation of endothelial mechanotransduction and thereby restores vascular homeostasis is needed. 
     SUMMARY OF THE INVENTION 
     The system and method of the present application is designed to reverse endothelial dysfunction through activation of the paracrine and autocrine processes in the endothelium. A method for creating endothelial mechanotransduction is disclosed. It provides a method for generating enhanced blood flow. By treating large areas of the body with multiple treatment pads, and by treating with sequential, overlapping intervals of contractions from distal to proximal, the method “milks” blood from the extremities, elevating blood flow and venous return. 
     This upregulated blood flow, by frictional drag on the endothelial wall, elevates laminar shear stress and increases mechanotransduction. Through mechanotransduction, the autocrine/paracrine functions of the endothelial cells increase the production of vasoactive substances including nitric oxide, prostacyclin, SOD and many others. Advantages of the invention include a cost-effective, non-invasive, drug-free treatment for a wide variety of vascular-related illnesses including atherosclerosis, hypertension, heart failure, vasculitis, neuropathy, chronic wounds and the effects of diabetes. 
     The method includes the use of a specific waveform generating device. Its specific electrical current and specific waveforms need only to be adequate to induce short periods of tetanic skeletal muscle contractions which will compress the venous system and, by way of the one-way valves in the veins, pump the blood toward the heart. This is generally known as the venous muscle pump. The treatment of endothelial dysfunction by physical movement of blood is a new and improved method. 
     An object of the present application is to provide the benefits of endogeneous (generated inside the body) NO and the restoration of endothelial function, without the disadvantages and potential side effects of drug use. Another object of the present application is to describe a system and method configured to provide a process and device having an adequate number of leads to treat the large areas of the body and to generate the volume and velocity needed to induce or increase therapeutic levels of endothelial mechanotransduction. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The novel features believed characteristic of the application are set forth in the appended claims. However, the application itself, as well as a preferred mode of use, and further objectives and advantages thereof, will best be understood by reference to the following detailed description when read in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a view of the general configuration of the electrical stimulation system according to the preferred embodiment of the present application. 
         FIG. 2  is a view showing the cellular basis of mechanotransduction. 
         FIGS. 3 and 4  are a representative side view of the effects of the electrical stimulation system of  FIG. 1  on blood vessels. 
         FIG. 5  is a front view of a human body illustrating exemplary placement of treatment pads used with the electrical stimulation system of  FIG. 1 . 
         FIG. 6  is flowchart of the method of using the electrical stimulation system of  FIG. 1  with its therapeutic effects. 
         FIG. 7  is an exemplary side view of a human leg showing the pads of  FIG. 4  aligned with a particular vein. 
         FIG. 8  is an exemplary view showing the sequential operation of the electrical stimulation system of  FIG. 1  as used with the treatment pads of  FIG. 6 . 
     
    
    
     While the system and method of the present application is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the application to the particular embodiment disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the process of the present application as defined by the appended claims. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Illustrative embodiments of the preferred embodiment are described below. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developer&#39;s specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure. 
     In the specification, reference may be made to the spatial relationships between various components and to the spatial orientation of various aspects of components as the devices are depicted in the attached drawings. However, as will be recognized by those skilled in the art after a complete reading of the present application, the devices, members, apparatuses, etc. described herein may be positioned in other desired orientations. Thus, the use of terms to describe a spatial relationship between various components or to describe the spatial orientation of aspects of such components should be understood to describe a relative relationship between the components or a spatial orientation of aspects of such components, respectively, as the device described herein may be oriented in any desired direction. 
     The system and method in accordance with the present application overcomes one or more of the above-discussed problems commonly associated with conventional methods for the treatment of endothelial dysfunction. It is designed to treat endothelial dysfunction through activation of the paracrine and autocrine processes in the endothelium by creating endothelial mechanotransduction. The process involves providing electrical stimulation to skeletal muscles over large areas of the body with multiple treatment pads that are sequentially initiated in overlapping intervals to elevate blood flow and venous return. 
     This increased blood flow creates increased frictional drag on the endothelial wall between blood cells and the endothelial wall itself. This laminar shear stress directly applied to the endothelial wall creates mechanotransduction. Through mechanotransduction, the autocrine/paracrine functions of the endothelial cells increase the production of vasoactive substances including nitric oxide, prostacyclin, SOD and many others. This process avoids invasive procedures and the risks associated with drugs. These and other unique features of the device are discussed below and illustrated in the accompanying drawings. 
     The system and method will be understood, both as to its structure and operation, from the accompanying drawings, taken in conjunction with the accompanying description. Several embodiments of the system may be presented herein. It should be understood that various components, parts, and features of the different embodiments may be combined together and/or interchanged with one another, all of which are within the scope of the present application, even though not all variations and particular embodiments are shown in the drawings. It should also be understood that the mixing and matching of features, elements, and/or functions between various embodiments is expressly contemplated herein so that one of ordinary skill in the art would appreciate from this disclosure that the features, elements, and/or functions of one embodiment may be incorporated into another embodiment as appropriate, unless otherwise described. 
     The system and method of the present application is illustrated in the associated drawings. The assembly includes a controller, such as a waveform generating device. The controller induces an electrical current through a plurality of treatment pads coupled to a human body. The treatment pads are sequentially initiated by the controller in short overlapping periods. The electrical stimulation causes contractions which will directly compress the venous system. By way of the one-way valves in the veins, the sequential stimulation pumps the blood toward the heart. 
     Referring now to the drawings wherein like reference characters identify corresponding or similar elements in form and function throughout the several views.  FIG. 1  illustrates the general configuration of the electrical stimulation system  101 . System  101  includes controller  40  having a plurality of leads  42  that are connected together via treatment pads  44 . Treatment pads  44  are configured for attachment to the human body. A plurality of pads  44  are coupled along the same vein in a predetermined pattern. The pads  44 /leads  42  are used to conduct the waveforms into and through the tissue being treated. Knobs  41  are also included and serve as a means of controlling the intensity of the waveform transferred through pads  44 . An operator is able to regulate the waveform as needed. 
     Controller  40  is operated by electrical power provided through a power source. As seen in  FIG. 1 , a plug  48  and power cord  46  may be included. System  101  is configured to receive power from the power source and transmit an electrical stimulation signal through leads  42  to the skeletal muscles of the human body. Each vein is surrounded by muscles that, when stimulated, apply pressure directly to the veins in the same way the body normally does to move blood. System  101  is not limited to a particular power source or voltage. An example is an 18-volt power source. 
     Controller  40  is configured to process and regulate the timing and sequence of electrical stimulations. This may be done via a processing unit and a plurality of controlling devices, such as a timer, a rheostat, and a gating device for example. Controller  40  controls the duration, intensity, and sequence of the waveform. Controller  40  is configured to regulate the intervals of treatment at pads  44 . The length of time may be limited to one half second, up to a plurality of seconds for example. 
     It is understood that system  101  may include any number of leads  42  and pads  44 . Furthermore, pads  44  may be releasably coupled to the human body using methods common in the industry. Such methods may include, but are not limited to the use of adhesives, manual straps, hook and loop fasteners, elastic, and other garments. Each is configured to hold pads  44  in place during treatment. Additionally, although a wire lead has been described, the leads may use technology to permit wired and/or wireless methods of electrical transmission. 
     System  101  uses neuromuscular stimulation applied at multiple locations on any and all extremities of the human body to contract skeletal muscles in a sequential pattern, beginning from a distal location to a proximal location on the extremity. This increases the blood flow to the heart thereby instigating more frictional drag between blood cells and the endothelial layer. The shear stress produces increased mechanotransduction activating the paracrine and autocrine processes listed above. 
     Referring now also to  FIG. 2  in the drawings, a view showing the cellular basis of mechanotransduction is illustrated. As stated previously, the contraction of the skeletal muscles directly compresses the blood vessels in the body, causing increased blood flow in the blood vessels. Blood  70  flows through the blood vessels in a laminar fashion, meaning that blood in the center flows more rapidly than the blood adjacent to the endothelial cells  72  of the lining within the blood vessel. The flow is varied due to the frictional forces. These frictional forces create shear stress on the endothelial cells  72 . Shear stress transduces the stresses into chemical signals  73 . These chemical signals  73  travel through a calcium pathway to activate endothelial nitric oxide synthase (eNOS) which synthesizes citruline and nitric oxide (NO) from L arginine. Some of the NO immediately migrates into the smooth muscle cells  74  where it converts guanosine triphosphate into cyclic guanosine monophosphate. The cyclic guanosine monophosphate causes relaxation in the smooth muscle cells resulting in vasodilation. The balance of the NO, and other secretagogues, migrate into the veins and arteries. 
     Referring now also to  FIGS. 3 and 4  in the drawings, a representative side view of a blood vessel using system  101  is shown. As seen in  FIG. 3 , electrical stimulation causes the skeletal muscles  57  to contract (see arrows  58   a ) which compresses the vein  50 . This compression forces the blood  56  both proximally and distally, thereby closing the distal one-way valve  54   b  and leaving open only the proximal valve  54   a . This forces the blood  56  into the next proximal segment of the vein. 
     As seen in  FIG. 4 , as the stimulation ends, the muscles  57  relax (see arrows  58   b ) which enlarges the vein  50 , creating a negative hydraulic pressure which causes the proximal valve  54   a  to close and the distal valve  54   b  to open, drawing blood  56  from the next distal segment of the vein. 
     Referring now also to  FIG. 5  in the drawings, a front view of a human body illustrating exemplary placement of treating pads  44  as used with system  101  is illustrated. Each pad  44  is in electrical communication with controller  40 . The pads  44  are routed so as to follow a continuous vein path back to the heart. A first route is seen in the right leg of the body and a second route is seen in the left leg of the human body. Each route is regulated through controller  40 . Each route may be regulated simultaneously or independently. Additionally, the stimulation of the skeletal muscles within each route may be stimulated either simultaneously or independently between the routes. The pads  44  are arranged in pairs wherein each treatment pair is aligned in approximately 180 degree opposed placement relative to one another. 
     Referring now also to  FIG. 6  in the drawings, a flowchart of the method of using system  101  with its therapeutic effects is illustrated. Chart  201  shows the sequence of actions which occur during use of system  101  and the possible therapeutic consequences which result from the application of the present invention to a human subject. As seen in chart  201 , controller  40  selectively provides electrical stimulation to leads  42  through pads  44  which thereby contracts the skeletal muscles. This contraction increases the blood flow in the veins which thereby does at least 2 things: (1) increases laminar stresses to induce endothelial mechanotransduction; and (2) increases the delivery of O 2  and other nutrients to the body by way of the capillaries. The benefits of each is therein illustrated in chart  201 . 
     This is a unique application method for neuromuscular electrical stimulation requiring the chronic (at least 30-days duration) application of treatments over a large area of the body (all four extremities is the preferred embodiment), and by the overlapping, sequential method in order to create endothelial mechanotransduction at a sufficient magnitude to reach therapeutic levels of vasoactive substances. 
     The nature and magnitude of shear stress and mechanotransduction play an important role in long-term maintenance of the structure and function of the blood vessel and is an important modulator of cellular function in the cardiovascular system. Data suggests that laminar shear stress stimulates cellular responses that are essential for endothelial cell function and are atheroprotective. Shear stress has an effect on endothelial-mediated alterations in coagulation, leukocyte and monocyte migration, smooth muscle growth, lipoprotein uptake and metabolism, and endothelial cell survival. Endothelial cell response to shear stress includes mechanotransducers (integrins, caveolae, ion channels, and G proteins), intermediate signaling molecules (c-Src, ras, Raf, protein kinase C), the mitogen activated protein kinases (ERK1/2, JNK, p38, BMK-1), and the production of nitric oxide (NO), prostacyclin, aldose reductase and many other vasoactive substances. 
     As a result of their unique location, endothelial cells experience three primary mechanical forces: (1) pressure, created by the hydrostatic forces of blood within the blood vessel; (2) circumferential stretch or tension, created as a result of defined intercellular connections between the endothelial cells that exert longitudinal forces on the cell; and (3) shear stress, the dragging frictional force created by blood flow. Of these forces, shear stress is a particularly important hemodynamic force because it stimulates mechanotransduction and the release of NO and other vasoactive substances, changes gene expression, cell metabolism, and cell morphology. 
     NO is a versatile and powerful molecule. It plays a fundamental role in controlling a range of simple bodily functions such as circulation of the blood, activities of the brain, lungs, liver, stomach, kidneys, genitals and other organs. It works in relaxing vascular and non-vascular smooth muscle cells, increasing local blood flow, decreasing local inflammation, inhibiting platelet aggregation and smooth muscle cell proliferation, reducing expression of cell surface adhesion proteins, and controlling neurotransmission. The lack of shear stress leads to a lack of bioavailability of NO, a condition commonly called endothelial dysfunction, and this may provide a mechanism by which risk factors such as hypertension, diabetes, hypercholesterolemia, and sedentary lifestyle act to promote atherosclerosis. Endothelial dysfunction is recognized as a significant health risk which contributes to atherosclerosis, hypertension, heart failure, vasculitis and diabetes. 
     Use of system  101  results in responses that range from instantaneous ion fluxes and biochemical pathways to gene and protein expression. Through the process of endothelial mechanotransduction, elevated levels of several substances, including nitric oxide, prostacyclin, thrombomodulin, superoxide dismutase, glutathione, Krupple-like factor 2, endothelial progenitor cells, and many others are created or elevated. This combination of increased blood flow (bringing nutrients and oxygen to the tissue) and the therapeutic effects of shear stress, mechanotransduction and the vasoactive substances have wide application and the potential to improve many serious ailments. 
     Treatment will be given to both lower and upper extremities to have whole-body benefits. Treatment begins by placing treatment pads on the patient in such a manner as to treat in sequential order beginning at the most distal portion with succeeding treatment pads placed proximally on the body. While there are generalized placement parameters, exact placement depends upon the condition being treated and the physiology of the patient. Pads  44  may be placed in anterior-posterior opposition or bilaterally, or other angles which may prove effective. 
     Once the pads  44  are in place, the operator initiates transmittal of waveforms through the pads  44  to the tissue. Beginning with the most distal pair of treatment pads on one extremity then moving to the next proximal pair of treatment pads, then the next, continuing in like manner until all pads on that extremity are gradually adjusted upward in intensity and the patient&#39;s comfort level is broached, then the intensity is slightly reduced. Each successive set of treatment pads is adjusted in like manner until all treatment pads are receiving waveforms just below the outer limits of the patient&#39;s comfort zone. After one side of the body has all treatment pads adjusted, proceed to the contralateral extremity and repeat the same sequence of adjustments. Once all treatment pads are receiving waveforms, it may be necessary to adjust the intensity of some or all of the treatment pads. 
     During the course of treatment, it will be necessary to adjust the intensity up or down (titration) as the patient becomes adjusted to the treatment, or as the nerves become more sensitive to stimulation. The preferred level of treatment is just below the patient&#39;s maximum tolerance level. 
     The treatment will normally last about one hour, but there may be situations where more or less time will be indicated. An example of a possible treatment regimen is to have 3 to 5 treatments a week for 4 to 8 weeks. It is essential that the overall treatment be administered chronically to achieve the full therapeutic benefits. One such desired benefit is the development of collateral circulation which will continue to contribute to blood flow after completion of the course of treatments. 
     Referring now also to  FIG. 7  in the drawings, a more detailed exemplary side view of a human leg showing the pads  44  (denoted by the circled numbers  1 ,  2 ,  3 , and  4 ) aligned with a particular vein. As seen, the muscles are selectively contracted and released at each location on the extremity. 
     Referring now also to  FIG. 8  in the drawings, the sequential nature of system  101  is shown in more clarity.  FIG. 8  shows a single vein having a plurality of muscles  57   a / 57   b  with a plurality of valves  54   a / 54   b . The vein is illustrated in four sequences. Each sequence is used to show the operation of controller  40  to induce proper blood flow. In sequence  1 , muscle  57   a  is contracted through electrical stimulation via one or more leads at a particular location on the body. The contraction of those muscles pushes blood out both proximally and distally, thereby closing the distal one-way valve  54   b  and leaving open only the proximal valve  54   a  (see also  FIGS. 3 and 4 ). This forces the blood  56  into the next proximal segment of the vein. The valves in all the proximal segments are open to permit blood flow. 
     While muscles  57   a  remain contracted, muscles  57   b  are then also contracted as seen in sequence  2 . By maintaining the contraction of muscles  57   a  while next stimulating the contraction of muscles  57   b , the blood is ensured to continue flowing to the next proximal segment. The process continues through the remaining sequential steps (sequence  3  and  4 ) until all leads in on the vein have been stimulated. The process of maintaining at least two neighboring stimulated muscles at a single time is important. As seen in  FIG. 8 , system  101  may be configured to sequentially stimulate all muscles in order without the release of any prior muscles until the entire vein has been stimulated. For example, system  101  could be configured to maintain the stimulation of the muscles in sequential order from muscles  57   a  through each set of muscles until the final set are stimulated (illustrated in sequence  4 ). It is understood that system  101  may also be configured to selectively cease stimulation of particular muscle groups during the entire sequence. For example, once muscles  57   c  are stimulated, controller  40  destimulates muscles  57   a . With either of the stimulation methods above, once the last muscle group is stimulated, the entire sequence is started over. This repeats itself for a predetermined time frame for each treatment session. 
     The current application has many advantages over the prior art including at least the following: (1) improves endothelial dysfunction through activation of the endocrine, paracrine and autocrine processes in the endothelium; (2) treating large areas of the body with multiple treatment pads using sequential overlapping intervals of contractions from distal to proximal so as to elevate blood flow and venous return; (3) increase laminar shear stress to trigger endothelial mechanotransduction; and (4) providing the benefits of endogeneous NO (and many other helpful vasoactive substances) and the restoration of endothelial function without the disadvantages and potential side effects of drug use. 
     The particular embodiments disclosed above are illustrative only, as the application may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. It is therefore evident that the particular embodiments disclosed above may be altered or modified, and all such variations are considered within the scope and spirit of the application. Accordingly, the protection sought herein is as set forth in the description. It is apparent that an application with significant advantages has been described and illustrated. Although the present application is shown in a limited number of forms, it is not limited to just these forms, but is amenable to various changes and modifications without departing from the spirit thereof.